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The Journal of American Science

ISSN 1545-1003

Volume 5 - Number 3 (Cumulated No. 19), May 20, 2009, ISSN 1545-1003

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The Journal of American Science ISSN 1545-1003

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The Journal of American Science

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Journal of American Science Volume 5 - Number 3, May 30, 2009, ISSN 1545-1003

Contents 1. The Power Conservation Scheme for Digital Picture Frames

Chien-Yuan Liu 1-7 2. Intelligence, Creativity and Gender as Predictors of Academic

Achievement among Undergraduate Students Habibollah Naderi, Rohani Abdullah, Tengku Aizan Hamid, Jamaluddin Sharir V. Kumar 8-19

3. Antibacterial Activity of the Extracts of Marine Red and Brown Algae P. Rajasulochana, R. Dhamotharan, P. Krishnamoorthy, S. Murugesan 20-25

4. Study of Structural and Mechanical properties of Zirconium Doped Cadmium Sulphide Thin Films

R. Thiyagarajan, M. Anusuya , M. Mahaboob Beevi 26-30

5. Evaluations of the Effects of Different Dietary Vitamin C levels on the Body Composition, Growth Performance and Feed Utilization Efficiencies in Stinging Catfish, Heteropneustes fossilis Md. Jobaer Alam, Md. Ghulam Mustafa, Md. Abdul Khaleque 31-40

6. A Survey of Blood Lead Levels in Pregnant Women attending two Public Prenatal Clinics in Nairobi City, Kenya Owago Joshua Odhiambo, Jane Murungi and Caroline Lang’at-Thoruwa 41-51

7. Applying Ordinal Association Rules for Cleansing Data With Missing Values Azzam Sleit, Mousa Al-Akhras, Inas Juma, Marwah Alian 52-62

8. Temporal Object-Oriented System (TOS) for Modeling Biological Data Abad Shah, Syed Ahsan, Ali Jaffer 63-73

9. Susceptibility To Infection Among Nickel Electroplaters El Safty A.m.k. , Fatehya.M.Metwaly , Hind M.Rashd.and Faten S.Bayoumi 74-82

10. Effects of cut-off ratio on performance of an irreversible Dual cycle

Rahim Ebrahimi 83-90

11. Nervilia gammieana (Hook.f.) Pfitzer (Orchidaceae) – a new record for Kumaun Himalaya, India

Jeewan Singh Jalal, Lalit M. Tewari and Y.P.S.Pangtey 91-94 12. Testing and Reliability Improvement of High Reliability Consumer

Electronics Products Manufactured on Printed Circuit Boards Ali Peiravi 95-106

13. Cyrtomium macrophyllum (Makino) Tagawa (Dryopteridaceae ), New record for Eastern Himalaya, India

A.Benniamin, N.Siva, and A.Arockkiam,V.S. Manickam 106-107

© 2009 Marsland Press, the United States, [email protected]

Marsland Press Journal of American Science 2009:5(3) 1-7

1

The Power Conservation Scheme for Digital Picture Frames

Chien-Yuan Liu The Department of Computer Science and Information Engineering, Chengshiu University, Niaosong Township, Kaohsiung County, 833, TAIWAN, R.O.C. E-mail: [email protected]

Abstract: Because of dynamic display feature and multimedia capability, a digital picture frame is quite popular by people and art gallery recently. A digital picture frame normally could be supplied with wall power. However, for more flexible placement or exhibition, a battery power is more suitable choice for a digital picture frame. In battery supply case, power save issue is the key consideration to prolong the exhibition duration. This paper pre-sents an adaptive power control scheme for a digital picture frame and its wireless interface. The scheme was designed and functioned at the MAC layer of the IEEE 802.11 specification. The result of simulation showed that power consumption of the digital picture frame was ob-viously decreased and the operating period of it was greatly extended. Keywords: digital picture frame, IEEE 802.11, power save, WLAN

1 Introduction

The wireless local area networks (WLAN) have been interested by academic researchers and industry experts in the past 10 years. Modern in-formation appliances (IA) are usually networked to a control master, a PC server, over WLAN. The digital picture frames (DPF) are the typical prod-ucts of IA and are one of the main applications of the flat panel displays (FPD). A DPF deployed at home or in a gallery may in high probability be supplied merely by pre-charged battery cells. Thus, the power saving scheme of a DPF to prolong the operation duration is very important to enable more flexible applications of the DPF in exhibi-tions.

The power consumption of a DPF during standby mode is typically less that of that of active mode. A DPF aggressively sets itself into standby mode to save the most of energy during the inter-val while fewer visitors are present nearby. With

doze mode, the DPF could spend down to only 1% power of that of active mode. The DPF would set itself into sleep state during the middle rest inter-val. When it is required, the DPF can recover from standby mode in tens mini-second or can wake up from doze mode in less than a second. During the standby and doze mode, WALN is still synchro-nously networking to the control master for updat-ing pictures, reporting the number of visitors and the residual power of the DPF for the statistics of preventive maintenance. A commercial WLAN modules consume about 1500 mini-Watts, this would be a dominant part compared to the power consumed by a DPF at standby or doze mode. Therefore, WLAN will also need to work in the power save mode as much as possible to reduce the total power consumption of the DPF under standby or doze mode, especially.

This paper proposes a power saving scheme for the infrastructure WLAN with directional antennas. Besides setting a DPF into sleep state, the scheme

The Power Conservation Scheme for Digital Picture Frames Chien-Yuan Liu

2

also forces the WLAN interfaces at idle state into doze mode, which consumes only 10% power of the WLAN module at idle state. Hopefully, near 90% of the energy consumption of WLAN could be conserved through the application of the scheme. Hence, the standby duration of the DPF is extended obviously and the battery replacement overhead is alleviated accordingly. A simulation will be conducted to verify the power saving effect

of the proposed scheme for the infrastructure WLAN.

2 The IEEE 802.11 WLAN

The IEEE 802.11 specification includes MAC layer and physical layer. Firstly, we briefly intro-duce the terms defined in IEEE 802.11 standard. For the detailed description is described in the ANSI/IEEE standard [1].

A Wireless Medium (WM) is a medium used to implement the transfer of protocol data unit (PDU) between the peer physical layer (PHY) en-tities of WLAN. A Station (STA) is any device that contains IEEE 802.11 conformant MAC and PHY interface to the WM. Multiple STA working in either distributed coordination function (DCF)

mode or point coordination function (PCF) mode form a basic service set (BSS). The BSS covered area is named the basic service area (BSA). A BSS can either be an infrastructure network or an inde-pendent ad hoc network.

An ad hoc network composed solely of stations within mutual communication range of each other via the WM. An ad hoc network is typically cre-ated in a spontaneous manner. The principal dis-

tinguishing characteristic of an ad hoc network is its limited temporal and spatial extent. These limi-tations allow the act of creating and dissolving the ad hoc network to be sufficiently straightforward and convenient. In contrast, an infrastructure net-work consists of an access point (AP) and some STA. The AP acts as a point coordinator (PC) of a BSS. Typically, a STA connects to the Internet through the bridging or the routing function of the AP. Several AP forms an extended service set (ESS) via the wired network system. Thus, larger area can be serviced by the infrastructure WLAN.

There are two service control functions speci-fied in the IEEE 802.11 MAC [7]. One is the PCF and the other is the DCF. The DCF provides con-tention based service, whereas the PCF provides a contention free service. In an infrastructure net-

Figure 1: An e xa mple of P CF fra me tra ns fe r

P IFS

NAV

Re s e t NAV

Conte ntion P e riod

Conte ntion-Fre e Re pe tition Inte rva l

Conte ntion-Fre e P e riod

Be a con D1 + poll D2 + a ck + pollD3 + a ck + poll D4 + poll

U1 + a ck U2 + a ck U4 + a ck

No re s pons e to CF-P oll

CF-End

CF_Ma x_Dura tion

S IFS

S IFSS IFS

S IFS S IFS P IFS

S IFS

S IFS

Dx = Fra me s S e nt by P CUx = Fra me s S e nt by polle d s ta tions


3

work, an AP utilizes the PCF function to become the PC to coordinate the communications of all STA. The rate of contention free period (CFP) and contention period (CP) can be defined in the bea-con frame. At very beginning, the PC broadcasts a beacon frame with a time stamp and a contention free (CF) parameter set. The time stamp is used for the time synchronization between the PC and all mobile STA (MS). The CFPMaxDuration in the CF parameter set is used by all MS to preset their network allocation vector (NAV). This prevents the contention by the non-polled transmission. Thus, all MS can operate properly in the CFP when the PC is operating.

A STA indicates it CF-Pollability using the CF-Pollable subfield of Association and Reasso-ciation Request frames. During a CFP, a PC is a polling master and all the MS, those are CF-Pollable and are included on polling list, act as slaves. The polling list is a logical structure se-quenced by the association identifier (AID) of each STA and is used to force the polling of CF-Pollable STA. The PC performs a poll for each of the MS on the polling list. When polled by the PC, a CF-Pollable STA may transmit only one MPDU and may piggyback the acknowledgment of a frame received from the PC. The polled STA shall reply a NULL frame if there is no data frame

to be sent. The PC can transmit data frame to a CF-Pollable STA and a non-CF-Pollable, a non-power-save STA. An example of frames transfer under PCF is illustrated in Figure 1.

CF-Pollable STA that are not on the polling list and did not request never to be polled, may be dy-namically placed on the polling list by the PC to handle bursts of frame transfer activity by that STA. A CF-Pollable STA, which has no data to transmit, may operate in the power-save (PS) mode and shall normally exclude itself to the poll-ing list. The STA shall synchronously wake up at the beginning per beacon frame to hear for the data frame indication in the beacon frame. The PC shall buffer data frames for those CF-Pollable STA with PS and shall inform those STA with the traffic indication map (TIM) in the beacon frame. Thus, the STA may put its radio into sleep mode for power save during CFP if there is no data indica-tion to it in the TIM. The STA shall at least wake up until the end of CF-End if it finds a data indica-tion for it.

3 Power Conservation Scheme

Advances in beam-forming technology have motivated current research to review some of the problems in wireless networking. Greater spatial

F igu re 2 : An e xa m p le o f b e a m fo rm s in two BS A

BS A1 BS A2

AP 2AP 1

NB4NB3 NB1 NB2


4

reuse and longer communication range are poten-tial benefits of utilizing directional antenna [13], [14], [18], [20]. Assume that the antenna system can offer two modes of operation: Omni and Di-rectional. In addition, a node can operate only in one mode at a given time, but can toggle between modes with negligible latency. The gain of direc-tional beamform is higher than that of Omni-direc-tional one. Therefore, longer communication dis-tance can be expected by the recipient STA or less power can be used to transmit a frame by the source STA.

An AP often uses the power source on the wall. Hence, there is no power shortage problem of the AP. The AP can freely operate its beamform in Omni-direction to transmit or receive frames. As for a mobile STA, the pre-charged power is scarce. To save energy, the STA tunes its beamform in the direction toward the AP. As mentioned previously, the STA will get higher signal to noise ratio (SNR) when receiving with directional beamform, and will consume less power when transmitting a frame to the AP. Besides power-save effect, it is also possible to reduce the co-channel interference to a nearby BSA.

In Figure 2, two nearby BSA are coordinated by the AP1 and AP2, respectively. The AP1 and AP2 send CF-Poll to their mobile STA in the cor-responding BSA by Omni-directional transmission. During receiving, the NB1 (STA1) adjusts its radio beamform to the direction of the maximal receiv-ing signal, which is the direction toward the AP1. With the beamform, consecutive frames for the NB1 will be received with better SNR compared to that of using Omni-directional beamform. After-ward, the acknowledgment or data frame to be sent to AP1 can be transferred with less power over the directional beamform on the uplink. In the mean-while, the NB2 (STA2) also uses the directional beamform to transfer/receive frames to/from the

AP2. With directional transmissions, the probabil-ity of interference between the two replies from NB1 and NB2 can be greatly reduced.

Without using power control, a pair of a source node and a destination node would normally use the maximal power to communicate. Many re-search results [6], [11], [15], [17] show that the power control not only saves power for the mobile nodes, but also increases spatial reuse and de-creases co-channel interference to the neighboring wireless networks. Thus, the power control scheme was adopted in the directional MAC. Note that from the initial communications, the recipient can obtain the least required power Plr from equation (1) [2]. Since power save is important to a mobile STA, the Plr will be used for consecutive frame transmission from the STA. Let Pt be the maximal transmitting power level of the STA, Pr be the received power level at the AP, Rxthresh be the nec-essary minimal receiving signal strength charac-terized by the recipient, and c be a comparison parameter to involve the gain effect from direc-tional antenna, hence

tlr thresh

r

PP Rx cP

= × ×

During the initial communications, the AP calculates the Plr for the STA and sends the value to the STA using the management frame. Upon receiving the frame with Plr, the STA know the least required power to transmit a frame to reach the AP. Practically, the Plr is much less than the maximal power Pt. Therefore, the power value of Pmax-Plr can be conserved by the power control scheme.

4 Performance Evaluation

To prove the effectiveness of the proposed method, we develop a simulation program to measure the energy consumption data for the per-formance evaluation of an infrastructure network

(1)


5

with directional antenna worked under the IEEE 802.11 PCF. In the simulation, 10 DPF are ran-domly deployed in an indoor building with an area of 30m ∗ 30m. The display dimension of each DPF is 6 inches ∗ 8 inches. The DPF equipped with 2AH battery cells and it consumes 5W during normal operation, including a 1500mW WLAN interface card to communicate with an AP located at the middle of the indoor building. Assume that the WLAN has a directional antenna which can control its beamform toward a certain sector cov-ering 120 degree scope. The duty rate of DPF was assumed to be 20% to represent the rate of visiting time. All the setting parameters were listed in Ta-ble 1.

Table 1: Simulation Parameters

Parameter Value Network Size 30m ∗ 30m MAC Function PCF The number of DPF 10 DPF Dimension 6 ∗ 8 inches Power 5W Battery Cells 2AH Input DC Voltage 12V WLAN Power 1500mW Visiting Duty Rate 20% The Scope Degree of Directional Antenna

120°

The simulation was executed ten times to

gather the averaged residual energy at all DPF. In each execution, the location of the DPF was dy-namically deployed by a random function. Initially, all battery cells of the DPF were fully pre-charged. Assume that a DPF would put itself into sleep sate when there is no visitor in front of the DPF for 10 seconds. The DPF would wake up immediately if a

visitor comes to the front of the DPF. This could be achieved by installing an approach sensor on the DPF to detect there is any visitor or not.

Several power saving methods were compared during the simulation. The SIM-1 represents the DPF was working all the time and there is no any power saving scheme and no power control func-tion implemented on its Omni-directional WLAN. The SIM-2 denotes the sleep mode was enabled by the DPF yet the other conditions were the same as the SIM-1. Based on the SIM-2, the directional antenna controlled by the least required power was amended into the SIM-3 method. The SIM-4 added the PCF power saving scheme onto the SIM-3 to conserve more energy.

In Figure 3, the y-axis indicates the averaged residual energy of the batteries of all DPF. 100% means the battery is with full capacity. The resid-ual energy was decreased when the simulation time was passing along. The x-axis describes how many hours were passing from the start of the simulation. One can read from the figure that the SIM-1 consumed the most energy among all methods. With SIM-1, the DPF would operate merely 5 hours in average. The operating lifetime is too short, so the replacement work would be too often for the host of the building. The residual en-ergy of the DPF by the SIM-2 was greatly im-proved by putting the DPF into the sleep state. It can work more than two working days under nor-mal visiting manner. After using the direction an-tenna, more energy can be saved in the SIM-3. With the SIM-3, a DPF could continuously operate about 4 days without the need to replace or re-charge its battery. Longer operation lifetime and less interference could be obtained by the SIM-4 because it adapted the PCF power saving scheme and the least required power by the power control. With SIM-4, it is possible to operate near 5 days and it could obviously relieve the overhead of re-


6

placement work by the host. If a little larger bat-tery was choose instead of the original 2AH bat-tery. The replacement period of the routine work would be extended to more than a week without difficulty.

Figure 3: Energy consumption Trends

5 Conclusions

Recently, WLAN was embedded into many IA. A DPF is one of the examples. The power of a portable IA is usually furnished by the battery cells. Hence, the operating lifetime is limited by the ca-pacity of the pre-charged battery cells.

To conserve energy for extending the working lifetime of an IA, several newer techniques for the power saving of the battery was proposed in our paper, including the directional antenna beam-forming and the power control on the WLAN of an IA beside the sleeping scheme of the IA.

To evaluate the effectiveness of our proposal, we compared our proposal to the standard IEEE 802.11 by using the simulation. The result shows that around 80% of energy can be saved under normal operation style. The operating lifetime is tremendously prolonged. References

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8

Intelligence, Creativity and Gender as Predictors of Academic Achievement among Undergraduate Students Habibollah Naderi1, Rohani Abdullah2, Tengku Aizan Hamid3, Jamaluddin Sharir4 V. Kumar5 1 Department of Educational Studies, University of Mazandaran, Street of Pasdaran, Babolsar, Iran 2Department of Human Development & Family Studies, University Putra Malaysia, Serdang, 43400, Malaysia

3Institute of Gerontology, University Putra Malaysia, Serdang, 43300, Malaysia 4Department of Educational Psychology and Counselling, University of Malaya, 50603 Kuala Lumpur, Malaysia 5 Department of English, University Putra Malaysia, Serdang 43400, Malaysia. Tel; +60389468733 Abstract: The purpose of this cross – sectional study was to assess prediction of intelligence, creativity and gender on academic achievement among undergraduate students. Participants (N= 153, 105 = male & 48= female) completed intelligence and creativity tests which were compared with their cumulative grade point average (CGPA). A multiple regression analysis indicated that intelligence, creativity and gender explained 0.045 of the variance in academic achievement, which is not significant, as indicated by the F- value of 2.334. Multiple regression analyses also indicated that intelligence and creativity (gender is controlled) together explained 0.010 of the variance in academic achievement, which is also not significant, as indicated by the F- value of 1.562. Partial correlations between academic achievement and IQ, creativity scores and gender were non significant at .05. Coefficients also showed there is no significance between academic achievement and IQ and gender at .05, except for creativity (t= 2.008, p= 0.046). Finding shows predicting lower independent variables of this study (scores of intelligence, creativity and gender) on academic achievement (CGPA).[Journal of American Science 2009:5(3) 8-19] ( ISSN: 1545-1003) Keywords: Academic Achievement, Creativity, Intelligence, Gender Corresponding Authors; Dr Rohani Abdullah Department of Human Development & Family Studies, University Putra Malaysia, 43400 Serdang, Malaysia, Tel: +60389467081 1 Introduction

Academic achievement has been a topic of

considerable interest and research for a very long time. Countless numbers of studies have been undertaken which either focused exclusively on academic achievement or investigated academic achievement in relation to other cognitive, social, and personal factors. Most of these studies have sought to determine factors that enhance academic achievement. The implications of these relationships for education are apparent since achievement in skill, concepts, and content are the acknowledged goals of the education process (Palaniappan, 2005, p36).

Unlike creativity, which has been subjected to many different definitions, academic achievement or academic ability is relatively more easily defined, measured and interpreted (Palaniappan, 2005, p36). A myriad of factors have been identified as being

related to academic achievement. The three fundamental of which will be addressed in this study are: intelligence (Laidra, Pullmann, & Allik, 2007), creativity and gender (Palaniappan, 2005, 2007a, 2007b). .

In recent years many researches have been studies about affecting academic achievement and their correlation with other demographic and psychological factors(Aguirre Pérez, Otero Ojeda, Pliego Rivero, Ferreyra Martيnez, & Manjarrez Dolores, 2008; Boykin et al., 2005; Caprara, Barbaranelli, Steca, & Malone, 2006; Contessa, Ciardiello, & Perlman, 2005; Finn, Gerber, & Boyd-Zaharias, 2005; Gooden, Nowlin, & Frank Brown and Richard, 2006; Hong & Ho, 2005; Jeanne Horst, Finney, & Barron, 2007; Johnson,

Intelligence, Creativity and Gender as Predictors Habibollah Naderi et al.

9

McGue, & Iacono, 2006; Lipscomb, 2007; Magnuson, 2007; Martin, Montgomery, & Saphian, 2006; McNelis, Johnson, Huberty, & Austin, 2005; Noftle & Robins, 2007; O'Connor & Paunonen, 2007; Rimm-Kaufman, Fan, Chiu, & You, 2007; Trautwein, Lüdtke, Kِller, & Baumert, 2006; Wagerman & Funder, 2007). Accordingly, several researchers examined the relationships between academic achievement and intelligence(Al-Saleh et al., 2001; Allik & Realo, 1997; Fagan, Holland, & Wheeler, 2007; Gagné & St Père, 2002; Koke & Vernon, 2003; Laidra et al., 2007; Mayes & Calhoun, 2007a, 2007b; McGrew & Flanagan, 1997; Neisser et al., 1996; Rohde & Thompson, 2007; R. J. Sternberg et al., 2001; Watkins, Lei, & Canivez, 2007; Williams et al., 2002) as well as those on academic achievement and creativity (Cicirelli, 1965; Hirsh & Peterson, 2008a; Kobal & Musek, 2001; Struthers, Menec, Schonwetter, & Perry, 1996).

This study examines the extent to which

students’ intelligence is associated with their creativity and academic achievement. The aim of this research is to answer the following questions: “what are the relationships between intelligence, creativity and academic achievement?” and “what is the role of gender in academic achievement?”

1. 1 The Theoretical framework of this study

The theory applied in the present study is based on the triarchic abilities (practical, creative and analytical) measured by Sternberg's Triarchic Ability Theory (STAT). This theory explains the prediction of academic achievement, independent of general intelligence (Koke & Vernon, 2003). Sternberg, et al. (1996) reported data indicating that the triarchic abilities are related to the scores on four tests of intelligence: the Concept Mastery Test, The Watson-Glaser Critical Thinking Appraisal, the Cattell Culture-Fair test of g and a test of creative insight constructed by Sternberg and his colleagues. The highest correlations were found with the Cattell Culture-Fair test of g, which has been used extensively as a measure of general intelligence. The estimated correlations between the Cattell Culture-Fair test of general intelligence and the analytical, creative, and practical subtests of STAT are 0.68, 0.78, and 0.51, respectively (Koke & Vernon, 2003).

1.2 Past Research In recent years, different

researchers have studied the relationship between intelligence and academic achievement. Understanding the nature of the relationship between general cognitive ability and academic achievement has widespread implications for both practice and theory (Rohde & Thompson, 2007).

Watkins et al. (2007) stated that

there had been considerable debate regarding the causal precedence of intelligence and academic achievement. Some researchers viewed intelligence and achievement as identical constructs. Others believed that the relationship between intelligence and achievement was reciprocal. Still others asserted that intelligence was causally related to achievement. (Laidra et al., 2007) reported that students’ achievement relied most strongly on their cognitive abilities through all grade levels. Laidra et al (2007) studied the predictors of academic achievement in a large sample of 3618 students (1746 boys and 1872 girls) in Estonia. Intelligence as measured by the Raven’s Standard Progressive Matrices was found to be the best predictor of students’ grade point average (GPA) in all grades. (Deary, Strand, Smith, & Fernandes, 2007) reported a strong correlation between intelligence and academic achievement. They examined psychometric intelligence at the age of 11 years old and education achievement in 25 academic subjects at the age of 16. The correlation between a latent intelligence trait and a latent trait of educational achievement was 0.81. They discovered that general intelligence contributed to success in all 25 academic subjects.

Aitken Harris (2004) examined 404 adults ( 203 men and 201 women), who completed four scales of a timed, group administered, intelligence test, 10 personality scales, and a creativity measures. The findings from this study suggest that achievement had small to moderate positive correlations with an


10

intelligence factor (which included the creativity scales).

Fodor & Carver (2000) conducted an experiment on undergraduate engineering and science students from Clarkson University, a predominantly technological university. Prior to the experiment, the students completed the Thematic Apperception Test (TAT), which was scored for achievement motivation and Power motivation. There were 144 experimental participants, 48 in each of three experimental conditions: positive, negative, or no feedback concerning prior performance on an engineering problem. Achievement motivation correlated positively with creativity score in the positive and negative-feedback conditions (r = .43 and .38, respectively) but not significantly in the no-feedback condition (r = .10). Power motivation correlated positively with creativity in the positive-feedback condition (r = .32), and negatively in the negative-feedback condition (r = −.25), but not significantly in the no-feedback condition (r = .17). Birenbaum & Nasser (2006) reported similar gender effect on achievement. Research on gender differences on intelligence (Naderi, Abdullah & Tengku Aizan, 2008) reported no significance difference between males and females on intelligence. However, findings regarding gender differences in academic achievement are not unequivocal. Deary et al. (2007) found that there were sex differences in educational attainment. Girls performed better than boys on overall academic subjects (courses). There were also significant sex differences in all academic subject (courses) scores, except Physics. Girls performed better in every topic except in Physics. However, result shows the effect sizes of the sex differences were often substantial. In addition, (Naderi, et. al, 2008) found there were no significant gender differences on creativity on the whole. However, the findings revealed gender differences in subscales scores. According this result females scored higher than males in the initiative factor (t = 3.566, p = .000), while males scored higher than females in the environmental sensitivity factor (t = -2.216, p = .028).

1.3 The present study The present study examines the relative-score between academic achievement, intelligence and creativity. It attempts to provide an estimate of the

true association between academic achievement, intelligence and creativity by having fluid intelligence and creative perception inventory tests as predictors and cumulative grade point average, applied to undergraduate students. Another major issue addressed by the current study is the gender difference in academic achievement measured through the (CGPA).

2. Method and Materials 2.1 Participants One hundred and fifty-three Iranian undergraduate students in Malaysian Universities (31.4% females and 68.6% males) were recruited as respondents in this study. Their ages ranged from 18 to 27 years old for females (mean = 22.27, sd = 2.62) and 19 to 27 years old for males (mean = 23.28 and sd = 2.43). 2.2. Instruments 2.2.1 Catell Culture Fair Intelligence Test (CFIT-33a3) To evaluate the intelligence, every student was administered by a Scale 3 of the Catell Culture fair Intelligence Test (CFIT-3a). Roberto Colom, Botella, & Santacreu (2002) reported that this test is a well-known test on fluid intelligence (GF). Participants completed Cattell’s culture fair intelligence test battery to assess individual differences in fluid intelligence. 2.2.2 Khatena-Torrance Creative Perception Inventory (KTCPI)

Creative perception was

examined using KTCPI (Khatena-Torrance Creative Perception Inventory) (A. K. Palaniappan, 2005). The Khatena-Torrance Creative Perception Inventory is based upon the rationale that creative functioning is reflected in the personality characteristics of the individual, in the ways they think or the kind of thinking strategies they employ and in the products that emerge as a result of their creative strivings. The


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scale presents statements to which subjects are required to respond to. The responses reflect the extent to which the subjects function in creative ways (Palaniappan, 2005).

The KTCPI consists of 50 items for some thing about my self that require yes or no answers. Scoring of responses to this measure presents little difficulty and can be done by simple frequency counts of the positive responses on the total scale. There is no time limit for the scale but most subjects complete the checklist in 10 to 20 minutes. Scoring responses to items is done by counting the number of positive responses, giving a credit of 1 for each positive response. All blank responses are scored zero (Palaniappan, 2007). However, the test was translated into Persian Language. An example of a translated item where the student is required answering ‘’Yes”” or ‘’No’’ is:

I like adding to an idea تمايل دارم نظر جديد ارائه نمايم ‘’ or’’

The Cronbach Alpha established in the study was 0.779.

2.2.3 Cumulative Grade Point Average

For the purposes of this study, Cumulative

Grade point Average (CGPA) has been used as a proxy for academic achievement. The CGPA is calculated by dividing the total amount of grade points earned by the total amount of credit hours taken.

2.3 Procedure

Every undergraduate student in the study was examined using KTCPI, CFIT-3a and CGPA. The research questions posed for the study required identifying and analyzing the distributions and regression on academic achievement. Enter linear regression analysis (with the effect size statistic R2) was used to determine the most powerful predictors of CGPA scores using IQ, creativity scores and gender (male and female). For analysis, a probability level of .05 was chosen for statistical significance because of the large number of comparisons.

Independent and dependent variables were

divided by gender, with total scores and measures calculated. The samples were selected during the

regular course time. Written and oral instructions were given for all of the participants. Participants were allowed to choose to identify themselves or to answer the tests anonymously. Students received no rewards but each was given information on the detailed result of his/her tests. Scores for measures were entered into the SPSS.

A pilot study was conducted to test KTCPI (Persian language) and the validity of the questionnaires as well as assess the suitability of the data collection procedure. The pilot study was also conducted to test CFIT-3a. As a result of the knowledge and experience gained from the pilot study, some changes were made to improve the survey instrument and to finalize a work plan for field implementation of the data collection for the actual study. Questions on the questionnaire were also revised to improve clarity and coherence.

3. Results 3.1 Descriptive Statistics The data was analyzed on the basis of gender, and reported in following Tables.

Table 1 shows descriptive statistics of intelligence. The finding of this result indicated that the females’ mean score was not different from the males (male = 104.63, female =104.38, but standard deviation and range of the males (SD=16.35, range= 72) were greater than the females’ standard deviation (14.35) and range (60).


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Table1: Descriptive Statistics of Intelligence

Measure N Minimum Maximum Mean SD Range Total Score 153 69 141 104.55 15.70 72 Male 105 69 141 104.63 16.35 72 Female 48 69 129 104.38 14.35 60

In Table 2, the females’ mean score (33.21) was

greater than the males’ (31.90) for Creativity, but the standard deviations between females and males were not too much different (males = 4.36; females

= 4.55). In fact, the range of scores between two groups was the same (18).

Table 2: Comparisons of Creative Perception Inventory Scores of Males and Females (50 items) Measure N Minimum Maximum Mean SD Range

Total Score 153 21 41 32.31 4.45 20 Male 105 21 39 31.90 4.36 18 Female 48 23 41 33.21 4.55 18 Table3: Descriptive Statistics of CGPA Measure N Minimum Maximum Mean SD Range

Total Score 153 1.21 4.00 2.97 0.54 2.79 Male 105 2.09 4.00 3.00 0.53 1.91 Female 48 1.21 3. 73 2.89 0.56 2.52

Table 3 reveals that the females’ mean (2.89) score for cumulative grade point average was lower than the males’ mean score (3.00), but the standard deviations between females and males were not very different from each other (males=0.53 & females=0.56). In addition, the range scores for the females (2.52) was greater than males (1.91). However, Normal P-P Plot graphs (Expected Cumulative Probability by Observed Cumulative Probability) obtained for creativity scores are displayed in Figure 1 and 2.


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Figure.2 From the scatterplot of residuals against predicted values, we can see that there is a clear relationship between the residuals and the predicted value, consistent with the assumption of linearity.

Figure.1 Dependent variable; academic achievement (CGPA). The normal plot of regression standardized

residuals for the dependent variable also indicates a relatively normal distribution. 3.2 Academic achievement predictors

The following tables show multiple regressions (standard) between CGPA and scores of the intelligence, creativity and gender. Table.4 shows variables entered. Together, gender, intelligence and creativity explain 0.045 of the variance in academic achievement (CGPA), which is not significant, as indicated by the F-value in the following tables 6 and 8. Table10 indicates that while gender and IQ do not contribute to the variation in CGPA, creativity does explain the variation in CGPA (t= 2.008, P= 0.046).

Table. 5 shows when gender is controlled

for, IQ and creativity explain 0.010 of the variance in academic achievement, which is not significant, as indicated by the F- values in Tables 7 and 9. This

indicates that IQ and creativity do not contribute to the variation in CGPA.

3.3 Partial correlations Partial correlations in table 11

showed that independent variables (intelligence and creativity scores and gender) was not significantly related to academic achievement (CGPA) at P < 0.05. In table 11, partial correlation also showed that intelligence and creativity scores (gender is controlled) was not significantly related to academic achievement (CGPA) at p< 0.05.


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Table 4: Variables Entered Removed b

Variables Variables Method Mode Entered Removed

1 Gender, IQ, Enter Creativity,

a. All requested variables entered b. Dependent Variable: CGPA

Table 5: Variables Entered Removed b

Variables Variables Method Mode Entered Removed

1 IQ, Creativity Enter

a. All requested variables (IQ , Creativity) entered b. Dependent Variable: CGPA

Table 6: Model Summary b Mode R R Square Adjusted R Std. Error of Square the Estimate 1 0.212a 0.045 0.026 0.52991

a. Predictors : ( Constant) ( Creativity , IQ and Gender) b. Dependent Variable: CGPA

Table 7: Model Summary b Mode R R Square Adjusted R Std. Error of Square the Estimate 1 0.178a 0.032 0.019 0.53180

a. Predictors : ( Constant) ( Creativity , IQ) b. Dependent Variable: CGPA

Table 8: ANOVA b

Model Sum of Squares df Mean Square F Sig 1 Regression 1.966 3 0.655 2.334 0.076 a Residual 41.840 149 0.281 Total 43.806 152

a. Predictors: ( Constant, Gender, IQ , Creativity,) b. Dependent Variable: CGPA


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Table 9: ANOVA b

Model Sum of Squares df Mean Square F Sig 1 Regression 1.384 2 0.692 2.448 0.090 a Residual 42.422 150 0.283 Total 43.806 152

a. Predictors: ( Constant, IQ , Creativity,) b. Dependent Variable: CGPA

Table 10: Coefficients a Model Unstandardized Standardized t Sig. Coefficients Coefficients B Std.Error Beta Zero-order Partial 1 (Constant) 1.811 0.448 4.40 .000 IQ 0.003 0.003 0.82 1.015 0.312 0.101 0.083 Creativity 0.020 0.010 0.163 2.008 0.046 0.157 0.162 Gender 0.134 0.093 0.116 1.439 0.152 .095 0.117 Dependent Variable: CGPA Table 11: Coefficients a Model Unstandardized Standardized t Sig. Coefficients Coefficients B Std.Error Beta Zero-order Partial 1 (Constant) 2.092 0.405 5.160 .000 IQ 0.003 0.003 0.85 1.046 0.297 0.101 0.085 Creativity 0.018 0.010 0.147 1.819 0.071 0.157 0.147 Dependent Variable: CGPA 4. Discussion and Conclusion Findings from the present study demonstrate that on the whole, the independent variables were not predictors of academic achievement. In conclusion, our findings not support the importance of IQ and gender in predicting academic achievement scores. However, it supports the role of creativity in explaining CGPA at p< 0.05.

Previous studies have supported the relationships between IQ / creativity and academic achievement but they did not examine the extent to which IQ, creativity and gender predict the variation in academic achievement (CGPA). The result this study in relation to IQ and academic achievement is consistent with


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result obtained in previous studies (Gagné & St Père, 2002; Laidra et al., 2007; Mayes & Calhoun, 2007a, 2007b; McGrew & Flanagan, 1997; Neisser et al., 1996). In addition, the relationship found between creativity and academic achievement with studies conducted by Aitken Harris (2004), Cicirelli (1965) and Hirsh & Peterson (2008b).

The result provided some initial data supporting

the use of the Cattell Fair Culture Intelligence Test and Creative Perception Inventory as self report measure of intelligence and creativity. The CGPA was also used as a measure of academic achievement. However, the result of the study did not support that the conventional measure of IQ, creativity, and academic achievement as predictive of academic achievement measured by students’ CGPA. This may be due to the lack of control in the range of the CGPA scores in this specific population of high academic achievement, which was a limitation of the study. Thus, there is a need for future replication studies to use more representative samples than the present samples. Such assessment of the academic achievement with objective performance-based measures by judges such as academic achievement tests, teachers, and parents will aid to overcome some of the limitations of the study.

Future studies are also needed to determine the

relative significance of creativity, IQ and gender in predicting other area of CGPA, together with academic achievement tests, written expression, reading compression, mathematics and sciences achievement.

Acknowledgements

We would like to thank the administration officers at University Putra Malaysia, University Malaya, University Multimedia, University Lim KokWing and University Tenaga Malaysia for giving us information about Iranian

students at their Universities. We also thank the Iranian undergraduate who participated in this study.

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Antibacterial Activity of the Extracts of Marine Red and Brown Algae P. Rajasulochana*, R. Dhamotharan**, P. Krishnamoorthy@, S. Murugesan*** * Research Scholar & Lecturer, Industrial Biotechnology Dept., Bharat University, Chennai, India ** Reader, Dept. Plant Biology & Plant Biotechnology, Presidency College, Chennai, India @ Professor and Dean academic, Dept. Bioinformatics, Bharat University, Chennai. *** PG and Research Dept. of Plant Biology and Plant Biotechnology, Unit of Environmental Sciences and Algal Biotechnology, Pachaiyappa’s College, Chennai, India. E-mail: [email protected], Telephone: 91-9444222678

ABSTRACT :In the marine eco system, seaweeds are directly exposed and are susceptible to ambient micro organisms such as bacteria, fungi and viruses. Seaweed species of kappaphycus (red algae) and padina (brown algae) from the coast of Tamilnadu, India were tested in vitro for their antibacterial activities against different types of bacteria using disc diffusion method. Methanol was used for inhibition of different bacterias such as pseudomonas flouresences, staphylococcus aureus, vibriochloera and proteus mirabilis in the case of red algae. In the study, it is observed that kappaphycus maximum activity against pseudomonas flouresences, staphylococcus aureus and less inhibition on vibriochloera and proteus mirabilis. Benzene, n-hexane, ethylacetate, methanol, chloroform : methanol solvents were used for inhibition of staphylococcus aureus and E-coli. It is noted that chloroform : methonal is the best solution for extracting the effective antibacterial materials from the brown algae species. The chloroform: methanol solvent further used for antibacterial activity against eleven pathogenic bacterias. It is observed from the experiments that the extract residues of algae recorded maximum activity against staphylococcus aureus with an inhibition zone compared to other bacterias. The extract residues of brown algae did not show any effect on the growth of proteus vulgaris and psedudomonoaeruginosa.[Journal of American Science 2009:5(3) 20-25] ( ISSN: 1545-1003)

Keywords: Antibacterial activity, kappa sps, padina sps, marine algae

1. INTRODUCTION Commercially available varieties of marine macroalgae are commonly refered to as seaweeds. Macroalgae can be classified as red algae (rhodophyta),brownalgae (phaeophyta) or greenalgae (chlorophyta) depending on their nutrient and chemical composition. Red and brown algae are mainly used as human food sources. Seaweeds serve as an important source of bioactive natural substances. Seaweeds have been used as food stuff in the Asia diet for centuries as it contains carotenoids, dietary fibres, proteins, essential fatty acids, vitamins and minerals. Marine algae are exploited mainly for the industrial production of phycocolloids such as agar-agar, alginate and carrageenan, not for health aspects. Biostimulant properties of seaweeds are explored for use in agriculture and the antimicrobial activities for the development of novel antibiotics. Seaweeds have some of the valuable medicinal value components such as antibiotics, laxatives, anticoagulants, anti-ulcer products and suspending agents in radiological preparations. Fresh and dry seaweeds are extensively consumed by people especially living in the coastal areas. From the literature, it is observed that the edible seaweeds contain a

significant amount of the protein, vitamins and minerals essential for the human nutrition (Fayaz et al., 2005). The nutrient composition of seaweed varies and is affected by the species, geographic areas, seasons of the year and temperature of the water. Seaweeds have recently received significant attention for their potential as natural antioxidants. Most of the compounds of marine algae show anti-bacterial activities (Vairappan et al., 2001, Vlachos et al., 1996). Many metabolites isolated from marine algae have been shown to possess bioactive efforts (Oh et al., 2008, Venkateswarlu et al., 2007 and Yang et al., 2006).

Among the different compounds with functional properties, antioxidants are the most widely studied. Moreover the important role of antioxidants in human health has been demonstrated thus increasing the interest in such products and their demand by consumers. Marine algae serve as important resources for bioactive natural products (Illiopoulere et al., 2002; Metzger et al., 2002). Brazilian red algae have been found to have phenolic substances. Oxidative stress is an important factor in the genesis of pathology, from cancer to cardiovascular and degenerative disease (Parthasarathy et al., 2001; Croke et al., 2003). Fayaz et al. (2005) suggested the utility of

Antibacterial Activity of the Extracts P. Rajasulochana et al.

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Kappaphycus alvarezzi for various nutritional products including antioxidant for use as health food or nutraceutical supplement. Different parts of the thalli are also known to differ in their antimicrobial potential. Extracts prepared from fresh seaweed samples are reported to show negligible antimicrobial activity as compared to that obtained with dried seaweeds. Seasonal and geographical variation in the levels of antimicrobial activities of marine algae has been shown by many. However, information is lacking on the seasonal and geographic variations in the specific metabolites of marine algae of antimicrobial potential, especially for the marine algae of South India. The coastal region of Tamilnadu, South India support a rich vegetation of marine algae. These studies have shown a great diversity in the macroalgal community of the marine algal vegetation of the region. Among the macro algae of the region, the brown algae padina sps and one red algae kappa sps grow in abundance as dominant communities in the shores of Kanyakumari and Ramanthapuram Districts of Tamilnadu State, India. In the present study, antibacterial activities of the extracts of red and brown algae using different solvent systems have been investigated. 2. MATERIALS AND METHODS The marine red alga was collected from the sea coast of Rameshwaram, Tamilnadu, India and the marine brown alga was collected from the sea coast of kanyakumari and Ramanathapuram district of Tamilnadu, India. Both are used as the experimental algae to study their bioactivity. Samples were rinsed with sterile water to remove any associated debris. Sample was kept under sunshade for 7 days. After drying the sample, it was ground thoroughly to powder form. The powder was then used for the estimation of the antibacterial activity. The strains of pseudomonas flouresences, staphylococcus aureus, vibriochloera and proteus mirabilis for red algae, vibriocholerae, staphylococcus aureus, E- coli, bacillusmegaterium, citrobactersp, enterobactersp, klebsiellapneumoniae, salmonellatyphi, shigellaflexneri, pseudomonasaeruginosa, proteusvulgaris were obtained from the University of Madras, Guindy campus, Chennai, Tamilnadu, India. The

antibacterial activity of the extract was assayed using the disc diffusion method (Bauer et al., 1996). For inoculum preparation and assay of antibacterial activity, Muller-hinton agar was used. The bacteria were sub cultured and routinely maintained on both nutrient agar and Muller-hinton agar. Antimicrobial activity was evaluated using the agar diffusion technique in petridishes. Each extract was loaded on sterile filter paper discs and air dried. Indicator microbes were spread on muller-hinton agar plates with sterile effusion the discs were placed on plates. After incubation for 24 hours at 30°c, a clear zone around a disc was evidence of antimicrobial activity. Discs loaded with the extracting agents were tested as controls (Incitunes et al 2006). Nutrient Agar Beef extract 3.0 g, Peptone 5.0 g, Nacl 5.0 g, Agar 15.0 g, PH 7.2 The above were dissolved in one liter distilled water and sterilized at 121oC for 15 minutes. Muller Hinton Agar The medium contained in one liter of water Casein hydrolysate (enzymic) 17.5 g Beef infusion 30.0 g Soluble starch 1.5 g Agar 20.0 g The final PH of the medium after sterilization at 1.1 kg/cm2 to 7.4 ± 0.2 (at 25oC) (121oC) for 15 minutes was adjusted. 3.0 RESULTS AND DISCUSSION Extracts of red and brown seaweed were tested against bacteria. The results of primary screening test of red algae (Kappa species) are summarized in Table 1. In this study, five test pathogens were considered, namely, pseudomonas fluorescence, staphylococcus aureus, vibrio cholera, Proteus mirabilis towards study of inhibition of microbial growth by methanol extract. The plates were incubated at 37oC. The zone of inhibition of assay was scored (+), if it is ‹2mm, double positive (++), if the zone is 2mm. The results are presented in Table 1 and Figs. 1, 2,3 and 4 respectively.


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Table 1 Inhibition of Microorganisms by Methanol extract Plate-1 Plate-2 Plate-3 Plate-4 Volume

(In µl)

Pseudomo-nas fluore-scence

Staphylo-coccus aureus Vibrio cholera Proteus mirabi-lis

25 - + - -

50 + ++ - -

75 ++ +++ + -

100 +++ +++ ++ +

Fiho et al. (2002) found that hexane extract of gracilaria species (red algae) inhibits only bacillus subtiles in contrast our results showed that the methanol extract of kappa species (red algae) inhibited the bacterias, namely, pseudomonas fluorescence, staphylococcus aureus, vibrio cholera, proteus mirabilis.

For studies on the antibacterial activity of the extracts of the experimental brown algae, the five solvent systems used, namely, n-hexane, benzyne, ethyl acetate, methanol and the mixture of chloroform: methanol (2:1 v/v) were used. The bacteria staphylococcus aureus and E-coli were used as test organisms (Table 2). In this primary investigation, the algal extract

Antibacterial Activity of the Extracts P. Rajasulochana et

al.

23

prepared with mixture of chloroform and methanol (2:1 v/v) proved to be more effective than the other solvent systems used in inhibiting the growth of both staphylococcus aureus and E-coli on the muller-hinton agar plates. Methanolic extracts of the algae were able to exhibit only 25-30% maximum activity against test organisms (Table 2). The other solvent extract appeared to be ineffective in inhibiting the growth of staphylococcus aureus and E-coli in muller-hinton agar, based on these observations, further experiments on the antibacterial activities of the experimental algae were restricted to chloroform: methanol extracts only.

Chloform: methanol (2:1 v/v) extracts of experimental algae were prepared as described earlier and tested at a concentration of 700 μg/disc by disc diffusion method against 11 pathogenic bacteria, namely, vibriocholerae, staphylococcus aureus, E- coli, bacillusmegaterium, citrobactersp, enterobactersp, klebsiellapneumoniae, salmonellatyphi, shigellaflexneri, pseudomonasaeruginosa, proteusvulgaris. The results are presented in Table 2 and Figs 5 to 9. The extracts residues of algae recorded maximum activity against staphylococcus aureus with an inhibition zone. Bacillus megaterium, klebsiellapneumoniae, shigellafexneri and vibrocholera were also inhibited by the extract residues of the experimental algae. 32 to 50 % of maximum activity was observed against citroacitro species, entro bacter species and E-coli. The extract residues of the brown algae did not show any effect on the growth of proteus vulgaris. Some studies concerning the effectiveness of extraction methods highlight that the methanol extraction yields higher antibacterial activity than n-hexane and ethyl acetate whereas others report that chloroform is better than methanol and benzyne. It is clear that using organic solvent always provides a higher efficiency in extracting compounds for antibacterial activities comparative water based methods (Incituney, et al., 2006). According to our experimental results, mainly extract residues of the kappa sp. (red algae) and padina sp. (brown algae) have good antibacterial activity related compounds. The remarkable differences between our results and the results obtained in previous studies may be due to several factors. First of all, this can be

because of the intraspecific variability in the production of secondary metabolites, occasionally related to seasonal variations. Secondly, there may also be differences in the capability of the extraction protocols to recover the active metabolites and differences in the assay methods that would result in different susceptibilities of the target strains. This is an inevitable fact for all biochemical research because test materials have trace impurities (Incituney, et. al., 2006). Table 2 Antibacterial activity of the crude solvent extracts of the brown algae

Antibacterial activity %(max. activity)

Sl. No

Solvent used for extraction Staphylococcus

aureus E-coli

1 n-hexane ++ (10) - 2 benzyne + (7) ++ 3 Ethyl acetate ++ (10) ++ 4 methanol +++ (25) +++ 5 Chlorofoam:

methanol (2:1 v/v)

++++ (100) ++++

- no activity , + low activity (7-10 mm halo) ++ high activity (10-15 mm halo), +++ to ++++more activity (25-100 mm/halo) Table 3 Antibacterial activity proved chloroform: methanol (2:1 v/v) extract residue of the experimental brown algae Sl. No.

Test pathogen Zone of inhibition (cms) ± s.e

1 Bacillus megaterium 4.0 ± 0.063 (64.5)

2 Staphylococcus aureus 6.2 ± 0.128 (100)

3 citroacitro species 2.0 ± 0.032 (32.5)

4 entro bacter species 3.0 ± 0.086 (48.4)

5 klebsiella pneumoniae 3.8 ± 0.032 (61.3)

6 E-coli 2.2 ± 0.063 (35.5)

7 salmonellatyphi 3.6 ± 0.10 (58.1)

8 shigellafexneri 3.8 ± 0.063 (61.3)

9 proteus vulgaris nil 10 psedudomonoaeruginosa nil 11 vibrocholera 3.5 ± 0.07

(56.5)


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700μg extract residue/disc was used in the

assay Values given in parentheses indicate % maximum activity

Fig. 5 Bacillusmegaterium & Fig. 6 Citrobactr sp. & Fig. 7

Enterobacter sp. Salmonellatyphi E-coli Staphylococcus aureus

Fig. 8 Proteusvulgaris & Fig. 9 Pseuodomonasaeruginosa &

Klebsiellapneumoniae Shigellaflexneri

Antibacterial Activity of the Extracts P. Rajasulochana et

al.

25

SUMMARY AND CONCLUDING REMARKS Samples (red and brown algae) collected from different sites locate in the Kanyakumari and Ramanathapuram districts of Tamilnadu, India werescreened for antibacterial activity. Methanol was used for inhibition of different bacterias such as pseudomonas flouresences, staphylococcus aureus, vibriochloera and proteus mirabilis in the case of red algae. In the study, it is observed that kappaphycus maximum activity against pseudomonas flouresences, staphylococcus aureus and less inhibition on vibriochloera and proteus mirabilis. Benzene, n-hexane, ethylacetate, methanol, chloroform : methanol solvents were used for inhibition of staphylococcus aureus and E-coli. It is noted that chloroform : methonal is the best solution for extracting the effective antibacterial materials from the brown algae species. The chloroform: methanol solvent further used for antibacterial activity against eleven pathogenic bacterias. It is observed from the experiments that the extract residues of algae recorded maximum activity against staphylococcus aureus with an inhibition zone compared to other bacterias. The extract residues of brown algae did not show any effect on the growth of proteus vulgaris and psedudomonoaeruginosa. Finally, we conclude that marine macro algae (red and brown algae) from the South coast of Tamilnadu, India are potential sources of bioactive compounds and should be investigated for natural antibiotics. However, further work is required to identify these active compounds in kappaphycus sp. which is carrageeno phytic seaweed. REFERENCES

Mohamed, Fayaz, K.K. Namitha, K.N. Chidambara Murthy, M. Mahadeva Swamy, R. Sarada, Salma Khanam, P.V. Subbarao and G.A. Ravishankar, 2005. Chemical composition, Iron bioavailability and antioxidant activity of kappsphycus alvarezi (Doty). J. Agric. Food Chemi., 53: 792-797.

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Somepalli Venkateswarlu, Gopala K. Panchagnula, Aditya L. Gottumukkala, Gottumukkala V. Subbaraju, 2007. Synthesis, structural revision, and biological activities of

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Bauer, A.W., Kirby, W.M., Sherris, J.C. and Turck, M., 1996. Antibiotic susceptibility testing by a standardized single disk method. American Journal Clinical Pathology, 45: 493-496.

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Study of Structural and Mechanical properties of Zirconium Doped Cadmium Sulphide Thin Films R. Thiyagarajan1, M. Anusuya2 , M. Mahaboob Beevi3 1 Department of Physics, Urumu Dhanalakshmi College, Trichy, Tamil Nadu, India-620018 2, 3 Department of Physics, Trichy Engineering College, Trichy, Tamil Nadu, India-621132 Tel: +91-431-2650266, 09952767994, [email protected] , 3 [email protected] Abstract:

Thin films of Zirconium doped Cadmium Sulphide are grown from aqueous solution at temperature of 2500C by spray pyrolysis technique. The films were characterized by X-ray diffraction (XRD). It reveals that the films are of polycrystalline nature with grain size in the order of nanometers. Depth sensing indentation is a powerful experimental tool for determining mechanical properties of thin film. Present work is based on Oliver-Pharr theory to measure hardness and elastic modulus by using ultra low load micro hardness indenter unit. SEM studies indicate that the grains are uniformly distributed throughout the sample area.[Journal of American Science 2009:5(3) 26-30] ( ISSN: 1545-1003)

Keyword: Thin films; Elastic modulus; Hardness; Indentation testing 1. Introduction The term ‘thin film’ generally refers to layer of material with one dimension much smaller than the other two. Thin film materials have become technologically important in recent years. Some examples are Microelectronic integrated circuits, Magnetic information storage systems, optical, wear resistant and corrosion resistant coatings. The use of materials in thin film form is the need for small-scale devices, physical properties that

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