Search results for: methicillin resistance Staphylococcus aureus
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3666

Search results for: methicillin resistance Staphylococcus aureus

2766 The Effect of Aerobic Exercise on Glycemic Control in Prediabetes and Type 2 Diabetes

Authors: Chun-Chin Huang

Abstract:

Individuals with prediabetes increase the risk of developing type 2 diabetes. Exercise is a potent stimulator of skeletal muscle glucose uptake and thus good for maintaining glucose homeostasis. That could be a conducive method to improve blood glucose regulation and prevent type 2 diabetes without medication intake. The aim of this study was to summarize mechanisms of insulin resistance and investigate the beneficial effects of acute and chronic aerobic exercise on glycemic control in prediabetes and type 2 diabetes. Aerobic exercise regulates glucose homeostasis and reduces blood glucose, insulin concentrations. Therefore, the type of aerobic exercise brings positive effects to prediabetes and type 2 diabetes.

Keywords: insulin resistance, glucose sensitivity, impaired fasting glucose, impaired glucose tolerance

Procedia PDF Downloads 155
2765 Blast Load Resistance of Bridge Columns

Authors: Amir Kavousifard, Lan Lin

Abstract:

The objective of this study is to evaluate the effects of the detailing in the seismic design of reinforced concrete (RC) bridge columns on the blast load resistance. A generic two-span continuous RC bridge located in Victoria, British Columbia, which represents the highest seismicity in Canada, was examined in the study. The bridge superstructure consists of a single cell box girder while the substructure consists of two circular columns. The bridge was designed according to the 2006 Canadian Highway Bridge Design Code. More specifically, response spectrum analysis was performed to determine the seismic demands using CSI Bridge. The 3D blast load analysis is carried out in the platform of LS-DYNA. Two charge heights, i.e., one at the mid-height of the column and the other at the bottom of the column, are considered. For each height, three cases are analyzed in order to investigate the effects of standoff and charge weight on the structural response. The blast load resistance of the column is assessed in terms of the concrete failure mechanism, steel stress distribution, and column lateral displacement. The results from the study indicate that a column designed in accordance with the code requirements could survive during the blast attack. Spiral columns perform much better than tied columns. The results also show that the charge weight has more impact on the structural response than the standoff. These results are beneficial for the development of the Canadian standards for the design of bridges under blast loads.

Keywords: blast, bridge, charge, height, seismic, standoff

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2764 A Memristive Device with Intrinsic Rectification Behavior and Performace of Crossbar Arrays

Authors: Yansong Gao, Damith C.Ranasinghe, Siad F. Al-Sarawi, Omid Kavehei, Derek Abbott

Abstract:

Passive crossbar arrays is in principle the simplest functional electrical circuit, together with memristive device in cross-point, holding great promise in future high-density, non-volatile memories. However, the greatest problem of crossbar array is the sneak path current. In this paper, we investigate one type of memristive device with intrinsic rectification behavior to address the sneak path currents. Firstly, a SPICE behavior model written in Verilog-A language of the memristive device is presented to fit experimental data published in literature. Next, systematic performance simulations including read margin and power consumption of crossbar array, which uses the self-rectifying memristive device as storage element at cross-point, with respect to different crossbar sizes, interconnect resistance, ratio of HRS/LRS (High Resistance State/ Low Resistance State), rectification ratio and different read schemes are conducted. Subsequently, Trade-offs among reading margin, power consumption, and reading schemes are analyzed to provide guidelines for circuit design. Finally, performance comparison between the memristive device with/without intrinsic rectification behavior is given to show the worthiness of this intrinsic rectification behavior.

Keywords: memristive device, memristor, crossbar, RRAM, read margin, power consumption

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2763 The Behavior of Masonry Wall Constructed Using Biaxial Interlocking Concrete Block, Solid Concrete Block and Cement Sand Brick Subjected to the Compressive Load

Authors: Fauziah Aziz, Mohd.fadzil Arshad, Hazrina Mansor, Sedat Kömürcü

Abstract:

Masonry is an isotropic and heterogeneous material due to the presence of the different components within the assembly process. Normally the mortar plays a significant role in the compressive behavior of the traditional masonry structures. Biaxial interlocking concrete block is a masonry unit that comes out with the interlocking concept. This masonry unit can improve the quality of the construction process, reduce the cost of labor, reduce high skill workmanship, and speeding the construction time. Normally, the interlocking concrete block masonry unit in the market place was designed in a way interlocking concept only either x or y-axis, shorter in length, and low compressive strength value. However, the biaxial interlocking concrete block is a dry-stack concept being introduced in this research, offered the specialty compared to the normal interlocking concrete available in the market place due to its length and the geometry of the groove and tongue. This material can be used as a non-load bearing wall, or load-bearing wall depends on the application of the masonry. But, there is a lack of technical data that was produced before. This paper presents a finding on the compressive resistance of the biaxial interlocking concrete block masonry wall compared to the other traditional masonry walls. Two series of biaxial interlocking concrete block masonry walls, namely M1 and M2, a series of solid concrete block and cement sand brick walls M3, and M4 have tested the compressive resistance. M1 is the masonry wall of a hollow biaxial interlocking concrete block meanwhile; M2 is the grouted masonry wall, M3 is a solid concrete block masonry wall, and M4 is a cement sand brick masonry wall. All the samples were tested under static compressive load. The results examine that M2 is higher in compressive resistance compared to the M1, M3, and M4. It shows that the compressive strength of the concrete masonry units plays a significant role in the capacity of the masonry wall.

Keywords: interlocking concrete block, compressive resistance, concrete masonry unit, masonry

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2762 Community, Identity, and Resistance in Minority Literature: Arab American Poets - Samuel Hazo, Nathalie Handal, and Naomi Shihab Nye

Authors: Reem Saad Alqahtani

Abstract:

Drawing on minority literature, this research highlights the role of three contemporary Arab American writers, considering the significance of the historical and cultural contexts of the brutal attacks of 9/11. The focus of the research is to draw attention to the poetry of Samuel Hazo, Nathalie Handal, and Naomi Shihab Nye as representatives of the identity crisis, whose experiences left them feeling marginalized and alienated in both societies, and reflected as one of the ethnic American minority groups, as demonstrated in their poetry, with a special focus on hybridity, resistance, identity, and empowerment. The study explores the writers’ post-9/11 experience, affected by the United States’ long history of marginalization and discrimination against people of colour, placing Arab American literature with that of other ethnic American groups who share the same experience and contribute to composing literature characterized by the aesthetics of cultural hybridity, cultural complexity, and the politics of minorities to promote solidarity and coalition building. Indeed, the three selected Arab American writers have found a link between their narration and the identity of the exiled by establishing an identity that is a kind of synthesis of diverse identities of Western reality and Eastern nostalgia. The approaches applied in this study will include historical/biographical, postcolonial, and discourse analysis. The first will be used to emphasize the influence of the biographical aspects related to the community, identity, and resistance of the three poets on their poetry. The second is used to investigate the effects of postcolonialism on the poets and their responses to it, while the third understand the sociocultural, political, and historical dimensions of the texts, establishing these poets as representative of the Arab American experience. This study is significant because it will help shed light on the importance of the Arabic hybrid identity in creating resistance to minority communities within American society.

Keywords: Arab American, identity, hybridity, post-9/11

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2761 Comparing the Efficacy of Minimally Supervised Home-Based and Closely Supervised Gym Based Exercise Programs on Weight Reduction and Insulin Resistance after Bariatric Surgery

Authors: Haleh Dadgostar, Sara Kaviani, Hanieh Adib, Ali Mazaherinezhad, Masoud Solaymani-Dodaran, Fahimeh Soheilipour, Abdolreza Pazouki

Abstract:

Background and Objectives: Effectiveness of various exercise protocols in weight reduction after bariatric surgery has not been sufficiently explored in the literature. We compared the effect of minimally supervised home-based and closely supervised Gym based exercise programs on weight reduction and insulin resistance after bariatric surgery. Methods: Women undergoing gastric bypass surgery were invited to participate in an exercise program and were randomly allocated into two groups. They were either offered a minimally supervised home-based (MSHB) or closely supervised Gym-based (CSGB) exercise program. The CSGB protocol constitute two sessions per week of training under ACSM guidelines. In the MSHB protocol participants received a notebook containing a list of recommended aerobic and resistance exercises, a log to record their activity and a schedule of follow up phone calls and clinic visits. Both groups received a pedometer. We measured their weight, BMI, lipid profile, FBS, and insulin level at the baseline and after 20 weeks of exercise and were compared at the end of the study. Results: A total of 80 patients completed our study (MSHB=38 and CSGB=42). The baseline comparison showed that the two groups are similar. Using the ANCOVA method of analysis the mean change in BMI (covariate: BMI at the beginning of the study) was slightly better in CSGB compared with the MSHB (between-group mean difference: 3.33 (95%CI 4.718 to 1.943, F: 22.844 p < 0.001)). Conclusion: Our results showed that both MSHB and CSGB exercise methods are somewhat equally effective in improvement of studied factors in the two groups. With considerably lower costs of Minimally Supervised Home Based exercise programs, these methods should be considered when adequate funding are not available.

Keywords: postoperative exercise, insulin resistance, bariatric surgery, morbid obesity

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2760 The Adoption of Mobile Learning in Saudi Women Faculty in King Abdulaziz University

Authors: Leena Alfarani

Abstract:

Although mobile devices are ubiquitous on university campuses, teacher-readiness for mobile learning has yet to be fully explored in the non-western nations. This study shows that two main factors affect the adoption and use of m-learning among female teachers within a university in Saudi Arabia—resistance to change and perceived social culture. These determinants of the current use and intention to use of m-learning were revealed through the analysis of an online questionnaire completed by 165 female faculty members. This study reveals several important issues for m-learning research and practice. The results further extend the body of knowledge in the field of m-learning, with the findings revealing that resistance to change and perceived social culture are significant determinants of the current use of and the intention to use m-learning.

Keywords: blended learning, mobile learning, technology adoption, devices

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2759 Investigation of the Effect of Fine-Grained and Its Plastic Properties on Liquefaction Resistance of Sand

Authors: S. A. Naeini, M. Mortezaee

Abstract:

The purpose of this paper is to investigate the effect of fine grain content in soil and its plastic properties on soil liquefaction potential. For this purpose, the conditions for considering the fine grains effect and percentage of plastic fine on the liquefaction resistance of saturated sand presented by researchers has been investigated. Then, some comprehensive results of all the issues raised by some researchers are stated. From these investigations it was observed that by increasing the percentage of cohesive fine grains in the sandy soil (up to 20%), the maximum shear strength decreases and by adding more fine- grained percentage, the maximum shear strength of the resulting soil increases but never reaches the amount of clean sand.

Keywords: fine-grained, liquefaction, plasticity, shear strength, sand

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2758 Effects of Abiotic Stress on the Phytochemical Content and Bioactivity of Pistacia lentiscus L.

Authors: S. Mamoucha, N. Tsafantakis, Α. Ioannidis, S. Chatzipanagiotou, C. Nikolaou, L. Skaltsounis, N. Fokialakis, N. Christodoulakis

Abstract:

Introduction: Plant secondary metabolites (SM) can be grouped into three chemically distinct groups: terpenes, phenolics, and nitrogen-containing compounds. For many years the adaptive significance of SM was unknown. They were thought to be functionless end-products. Currently it is accepted that many secondary metabolites (also known as natural products) have important ecological roles in plants. For instance, they serve as attractants (odor, color, taste) for pollinators and seed-dispersing animals. Moreover, they protect plants from herbivores, microbial pathogens and from environmental stress (high and low temperatures, drought, alkalinity, salinity, radiation etc). It is well known that both biotic and abiotic stress often increase the accumulation of SM. The local climatic conditions, seasonal changes, external factors such as light, temperature, humidity affect the biosynthesis and composition of secondary metabolites. A well known dioecious evergreen plant, Pistacia lentiscus L. (mastic tree), was selected in order to study the metabolic variations occur in response to the different climate conditions, due to the seasonal variation and its effect on the biosynthesis of bioactive compounds. Materials-methods: Young and mature leaves were collected in January and July 2014, dried and extracted by accelerated solvent extraction (Dionex ASE™ 350) using solvents of increased polarity (DCM, MeOH, and H2O). GC-MS and UHPLC-HRMS analysis were carried out in order to define the nature and the relative abundance of SM. The antibacterial activity was evaluated by using the Agar Disc Diffusion Assay against ATCC and clinical isolates strains: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Streptococcus mutans and Klebsiella pneumoniae. All tests were carried out in duplicate and the average radii of the inhibition zones were calculated for each extract. Results: According to the phytochemical profile obtained from each extract, the biosynthesis of SM varied both qualitatively and quantitatively under the two different types of seasonal stress. With exception of the biologically inactive nonpolar DCM extract of July, all extracts inhibited the growth of most of the investigated microorganisms. A clear positive correlation has been observed between the relative abundance of SM and the bioactivity of the DCM extracts of January and July. Observed changes during phytochemical analysis were mainly focused on the triterpenoid content. On the other hand, the bioactivity of the polar extracts (MeOH and H2O) of January and July resulted practically invariable against most of the microorganisms, besides the significant variation of the SM content due to the seasonal variation. Conclusion: Our results clearly confirmed the hypothesis of abiotic stress as an important regulating factor that significantly affects the biosynthesis of secondary metabolites and thus the presence of bioactive compounds. Acknowledgment: This work was supported by IKY - State Scholarship Foundation, Athens, Greece.

Keywords: antibacterial screening, phytochemical profile, Pistacia lentiscus, abiotic stress

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2757 Double Negative Differential Resistance Features in Series AIN/GaN Double-Barrier Resonant Tunneling Diodes Vertically Integrated by Plasma-Assisted Molecular Beam Epitaxy

Authors: Jiajia Yao, Guanlin Wu, Fang Liu, Junshuai Xue, Yue Hao

Abstract:

This study reports on the epitaxial growth of a GaN-based resonant tunneling diode (RTD) structure with stable and repeatable double negative differential resistance (NDR) characteristics at room temperature on a c-plane GaN-on-sapphire template using plasma-assisted molecular beam epitaxy (PA-MBE) technology. In this structure, two independent AlN/GaN RTDs are epitaxially connected in series in the vertical growth direction through a silicon-doped GaN layer. As the collector electrode bias voltage increases, the two RTDs respectively align the ground state energy level in the quantum well with the 2DEG energy level in the emitter accumulation well to achieve quantum resonant tunneling and then reach the negative differential resistance (NDR) region. The two NDR regions exhibit similar peak current densities and peak-to-valley current ratios, which are 230 kA/cm² and 249 kA/cm², 1.33 and 1.38, respectively, for a device with a collector electrode mesa diameter of 1 µm. The consistency of the NDR is much higher than the results of on-chip discrete RTD device interconnection, resulting from the smaller chip area, fewer interconnect parasitic parameters, and less process complexity. The methods and results presented in this paper show the brilliant prospects of GaN RTDs in the development of multi-value logic digital circuits.

Keywords: MBE, AlN/GaN, RTDs, double NDR

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2756 Molecular Characterization of Functional Domain (LRR) of TLR9 Genes in Malnad Gidda Cattle and Their Comparison to Cross Breed Cattle

Authors: Ananthakrishna L. R., Ramesh D., Kumar Wodeyar, Kotresh A. M., Gururaj P. M.

Abstract:

Malnad Gidda is the indigenous recognized cattle breed of Shivamogga District of Karnataka state, India is known for its disease resistance to many of the infectious diseases. There are 25 LRR (Leucine Rich Repeats) identified in bovine (Bos indicus) TLR9. The amino acid sequence of LRR is deduced to nucleotide sequence in BLASTx bioinformatic online tools. LRR2 to LRR10 are involved in pathogen recognition and binding in human TLR9 which showed a higher degree of nucleotide variations with respect to disease resistance to various pathogens. Hence, primers were designed to amplify the flanking sequences of LRR2 to LRR10, to discover the nucleotide variations if any, in Malnad Gidda breed of Cattle which is associated with disease resistance. The DNA isolated from peripheral blood mononuclear cells of ten Malnad Gidda cattle. A desired and specific amplification product of 0.8 kb was obtained at an annealing temperature of 56.6ᵒC. All the PCR products were sequenced on both sides by gene-specific primers. The sequences were compared with TLR9 sequence of cross breed cattle obtained from NCBI data bank. The sequence analysis between Malnad Gidda and crossbreed cattle revealed no nucleotide variations in the region LRR2 to LRR9 which shows the conserved in pathogen binding domain (LRR) of TLR9.

Keywords: leucine rich repeats, Malnad Gidda, cross breed, TLR9

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2755 Study of Corrosion Behavior of Experimental Alloys with Different Levels of Cr and High Levels of Mo Compared to Aisi 444

Authors: Ana P. R. N. Barroso, Maurício N. Kleinberg, Frederico R. Silva, Rodrigo F. Guimarães, Marcelo M. V. Parente, Walney S. Araújo

Abstract:

The fight against accelerated wear of the equipment used in the oil and gas sector is a challenge for minimizing maintenance costs. Corrosion being one of the main agents of equipment deterioration, we seek alternative materials that exhibit improved corrosion resistance at low cost of production. This study aims to evaluate the corrosion behavior of experimental alloys containing 15% and 17% of chromium (Cr) and 5% of molybdenum (Mo) in comparison with an AISI 444 commercial alloy. Microstructural analyzes were performed on samples of the alloys before and after the electrochemical tests. Two samples of each solubilized alloy were also taken for analysis of the corrosion behavior by testing potentiodynamic polarization (PP) and Electrochemical Impedance Spectroscopy (EIS) with immersion time of 24 hours in electrolytic solution with acidic character. The graphics obtained through electrochemical tests of PP and EIS indicated that among the experimental alloys, the alloy with higher chromium content (17%) had a higher corrosion resistance, confirming the beneficial effect of adding chromium. When comparing the experimental alloys with the AISI 444 commercial alloy, it is observed that the AISI 444 commercial alloy showed superior corrosion resistance to that of the experimental alloys for both assays, PP and EIS. The microstructural analyzes performed after the PP and EIS tests confirmed the results previously described. These results suggest that the addition of these levels of molybdenum did not favor the electrochemical behavior of experimental ferritic alloys for the electrolytic medium studied.

Keywords: corrosion, molybdenum, electrochemical tests, experimental alloys

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2754 Edible Active Antimicrobial Coatings onto Plastic-Based Laminates and Its Performance Assessment on the Shelf Life of Vacuum Packaged Beef Steaks

Authors: Andrey A. Tyuftin, David Clarke, Malco C. Cruz-Romero, Declan Bolton, Seamus Fanning, Shashi K. Pankaj, Carmen Bueno-Ferrer, Patrick J. Cullen, Joe P. Kerry

Abstract:

Prolonging of shelf-life is essential in order to address issues such as; supplier demands across continents, economical profit, customer satisfaction, and reduction of food wastage. Smart packaging solutions presented in the form of naturally occurred antimicrobially-active packaging may be a solution to these and other issues. Gelatin film forming solution with adding of natural sourced antimicrobials is a promising tool for the active smart packaging. The objective of this study was to coat conventional plastic hydrophobic packaging material with hydrophilic antimicrobial active beef gelatin coating and conduct shelf life trials on beef sub-primal cuts. Minimal inhibition concentration (MIC) of Caprylic acid sodium salt (SO) and commercially available Auranta FV (AFV) (bitter oranges extract with mixture of nutritive organic acids) were found of 1 and 1.5 % respectively against bacterial strains Bacillus cereus, Pseudomonas fluorescens, Escherichia coli, Staphylococcus aureus and aerobic and anaerobic beef microflora. Therefore SO or AFV were incorporated in beef gelatin film forming solution in concentration of two times of MIC which was coated on a conventional plastic LDPE/PA film on the inner cold plasma treated polyethylene surface. Beef samples were vacuum packed in this material and stored under chilling conditions, sampled at weekly intervals during 42 days shelf life study. No significant differences (p < 0.05) in the cook loss was observed among the different treatments compared to control samples until the day 29. Only for AFV coated beef sample it was 3% higher (37.3%) than the control (34.4 %) on the day 36. It was found antimicrobial films did not protect beef against discoloration. SO containing packages significantly (p < 0.05) reduced Total viable bacterial counts (TVC) compared to the control and AFV samples until the day 35. No significant reduction in TVC was observed between SO and AFV films on the day 42 but a significant difference was observed compared to control samples with a 1.40 log of bacteria reduction on the day 42. AFV films significantly (p < 0.05) reduced TVC compared to control samples from the day 14 until the day 42. Control samples reached the set value of 7 log CFU/g on day 27 of testing, AFV films did not reach this set limit until day 35 and SO films until day 42 of testing. The antimicrobial AFV and SO coated films significantly prolonged the shelf-life of beef steaks by 33 or 55% (on 7 and 14 days respectively) compared to control film samples. It is concluded antimicrobial coated films were successfully developed by coating the inner polyethylene layer of conventional LDPE/PA laminated films after plasma surface treatment. The results indicated that the use of antimicrobial active packaging coated with SO or AFV increased significantly (p < 0.05) the shelf life of the beef sub-primal. Overall, AFV or SO containing gelatin coatings have the potential of being used as effective antimicrobials for active packaging applications for muscle-based food products.

Keywords: active packaging, antimicrobials, edible coatings, food packaging, gelatin films, meat science

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2753 Training Volume and Myoelectric Responses of Lower Body Muscles with Differing Foam Rolling Periods

Authors: Humberto Miranda, Haroldo G. Santana, Gabriel A. Paz, Vicente P. Lima, Jeffrey M. Willardson

Abstract:

Foam rolling is a practice that has increased in popularity before and after strength training. The purpose of this study was to compare the acute effects of different foam rolling periods for the lower body muscles on subsequent performance (total repetitions and training volume), myoelectric activity and rating of perceived exertion in trained men. Fourteen trained men (26.2 ± 3.2 years, 178 ± 0.04 cm height, 82.2 ± 10 kg weight and body mass index 25.9 ± 3.3kg/m2) volunteered for this study. Four repetition maximum (4-RM) loads were determined for hexagonal bar deadlift and 45º angled leg press during test and retest sessions over two nonconsecutive days. Five experimental protocols were applied in a randomized design, which included: a traditional protocol (control)—a resistance training session without prior foam rolling; or resistance training sessions performed following one (P1), two (P2), three (P3), or four (P4) sets of 30 sec. foam rolling for the lower extremity musculature. Subjects were asked to roll over the medial and lateral aspects of each muscle group with as much pressure as possible. All foam rolling was completed at a cadence of 50 bpm. These procedures were performed on both sides unilaterally as described below. Quadriceps: between the apex of the patella and the ASIS; Hamstring: between the gluteal fold and popliteal fossa; Triceps surae: between popliteal fossa and calcaneus tendon. The resistance training consisted of five sets with 4-RM loads and two-minute rest intervals between sets, and a four-minute rest interval between the hexagonal bar deadlift and the 45º angled leg press. The number of repetitions completed, the myoelectric activity of vastus lateralis (VL), vastus medialis oblique (VMO), semitendinosus (SM) and medial gastrocnemius (GM) were recorded, as well as the rating of perceived exertion for each protocol. There were no differences between the protocols in the total repetitions for the hexagonal bar deadlift (Control - 16.2 ± 5.9; P1 - 16.9 ± 5.5; P2 - 19.2 ± 5.7; P3 - 19.4 ± 5.2; P4 - 17.2 ± 8.2) (p > 0.05) and 45º angled leg press (Control - 23.3 ± 9.7; P1 - 25.9 ± 9.5; P2 - 29.1 ± 13.8; P3 - 28.0 ± 11.7; P4 - 30.2 ± 11.2) exercises. Similar results between protocols were also noted for myoelectric activity (p > 0.05) and rating of perceived exertion (p > 0.05). Therefore, the results of the present study indicated no deleterious effects on performance, myoelectric activity and rating of perceived exertion responses during lower body resistance training.

Keywords: self myofascial release, foam rolling, electromyography, resistance training

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2752 Role of Physical Properties of Maize Grains Towards Resistance to Sitotroga Cerealella (OLIV.) (Gelechiidae: Lepidoptera) in No Choice

Authors: Sohail Ahmed, Ahmad Raza

Abstract:

Physical properties of maize grains were correlated with levels of the life history of Sitotroga cerealella (Oliv.) (Gelechiidae: Lepidoptera) in no choice test to find out relative resistance in different varieties. Eight maize varieties /lines (EV-6089, Sahiwal-2002, Golden, 34N43, EV-1098, Sultan, China-1, EV-20) including seven yellow and one white were obtained from Maize and Millet Research Institute, Yousaf Wala, Sahiwal, Punjab, Pakistan. Freshly laid eggs (one day old) of S. cerealella were obtained and cultured on a susceptible maize variety for two generations for later on shifting to test varieties. Results showed that maximum moth emergence (10.33), fecundity (35.66), hatching (87.66%), moth weight (5.05 mg), development time (36.0 days) damage (93.35%) and grain weight loss (38.84%) was found in varieties, 34N43 and Golden, Sultan, Sahiwal 2002, 34N43, EV-6089, 34N43 and EV-1089, respectively. Varieties had significant difference with other varieties in these parameters (P<0.05). The varieties had positive as well as negative correlation between hardness index, grain weight and bulk density with the biological parameters of S. cerealella, percent grain damage and weight loss. Possible involvement of these grain properties in the resistance of maize grains towards S. cerealella is discussed.

Keywords: sitotroga cerealella, hardness index, grain damage, maize, varieties

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2751 Parental Diet Effects on Offspring Body Size and Pathogen Resistance in Bactrocera tryoni

Authors: Hue Dinh, Binh Nguyen, Vivian Mendez, Phillip W. Taylor, Fleur Ponton

Abstract:

Better understanding of how parental diet affects offspring traits is an important ecological and evolutionary question. In this study, we explored how maternal diet influences offspring physiology and resistance to infection using Bactrocera tryoni (Q-fly) as a system model. Female Q-flies were fed one of six single diets varying in their yeast-to-sugar ratio yielding six protein-to-carbohydrate ratios. As controls, we used females that were given a choice between yeast and sugar. Males were reared on a choice diet and allowed to mate with females 14 days post-emergence. Results showed that while maternal diet does not influence offspring developmental time, it has a strong effect on larval body weight. Mother fed either high-protein or high-sugar diet produced larger progeny. By challenging offspring with the bacterium Serratia marcescens, we found that female offspring from mothers fed high-sugar diet survived better the infection compared to those from mothers fed low-sugar diet. In contrast, male offspring produced by mother fed high-protein diet showed better resistance to the infection compared to those produced by mother fed low-protein diet. These results suggested sex-dependent transgenerational effects of maternal nutrition on offspring physiology and immunity.

Keywords: bacterial infection, Bactrocera tryoni, maternal diet, offspring, Serretia marcescens

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2750 Women Retelling the Iranian Revolution: A Comparative Study of Novelists Maryam Madjidi and Negar Djavadi

Authors: Alessandro Giardino

Abstract:

The Iranian Revolution has been the object of numberless historical and semi-fictional accounts, often providing a monolithic perspective on the events, due to the westerner positioning of those recounting them. Against this tradition, two contemporary French-Iranian novels "Disoriental" (2016) by Negar Djavadi and "Marx and The Doll" (2017) by Maryam Madjidi have offered readers a female-oriented and interestingly layered representation of the Iranian Revolution, hence addressing the responsibilities and misconceptions of Western countries. Furthermore, these two women writers have shed light on the disenchantment of the Iranian intellectual class vis-à-vis the foundation of the Islamic Republic, by particularly focusing on the deterioration of women’s rights, as well as the repression of political, ethnical, religious and sexual minorities. By a psycholinguistic and semasiological analysis of the two novels by Djavadi and Madjidi, this essay will focus on alternative accounts of the revolution in order to reflect upon the role of intersectional literature to the understanding of history. More specifically, as both women, refugees, and bi-cultural writers, Djavadi and Madjidi unearthed moments and figures of the revolution which had disappeared from the prevalent narrative. In doing so, however, these two writers resorted to entirely opposite styles of writing that, it will be argued, stem from different types of female resistance. In defining these two approaches as a "narrative resistance" and a "photographic resistance," the essay will elucidate the dependence of these writers’ language on generational and psychological factors, but it will also stir a reflection on their different communicative strategies.

Keywords: Iranian revolution, French-Iranian, intersectionality, literature, women writers

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2749 Mechanical Behavior of PVD Single Layer and Multilayer under Indentation Tests

Authors: K. Kaouther, D. Hafedh, A. Ben Cheikh Larbi

Abstract:

Various structures and compositions thin films were deposited on 100C6 (AISI 52100) steel substrate by PVD magnetron sputtering system. The morphological proprieties were evaluated using an atomic force microscopy (AFM). Vickers microindentation tests were performed with a Shimadzu HMV-2000 hardness testing machine. Hardness measurement was carried out using Jonsson and Hogmark model. The results show that the coatings topography was dominated by domes and craters. Mechanical behavior and failure modes under microindentation were depending of coatings structure and composition. TiAlN multilayer showed exception in the microindentation resistance compared to TiN single layer and TiAlN/TiAlN nanolayer. Piled structure provides an increase of failure resistance and a decrease in cracks propagation.

Keywords: PVD thin films, multilayer, microindentation, cracking, damage mechanisms

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2748 Development and Evaluation of Surgical Sutures Coated with Antibiotic Loaded Gold Nanoparticles

Authors: Sunitha Sampathi, Pankaj Kumar Tiriya, Sonia Gera, Sravanthi Reddy Pailla, V. Likhitha, A. J. Maruthi

Abstract:

Surgical site infections (SSIs) are the most common nosocomial infections localized at the incision site. With an estimated 27 million surgical procedures each year in USA, approximately 2-5% rate of SSIs are predicted to occur annually. SSIs are treated with antibiotic medication. Current trend suggest that the direct drug delivery from the suture to the scared tissue can improve patient comfort and wound recovery. For that reason coating the surface of the medical device such as suture and catguts with broad spectrum antibiotics can prevent the formation of bactierial colonies with out comprimising the mechanical properties of the sutures.Hence, the present study was aimed to develop and evaluate a surgical suture coated with an antibiotic Ciprofloxacin hydrochloride loaded on gold nanoparticles. Gold nanoparticles were synthesized by chemical reduction method and conjugated with ciprofloxacin using Polyvinylpyrolidone as stabilizer and gold as carrier. Ciprofloxacin conjugated gold nanoparticles were coated over an absorbable surgical suture made of Polyglactan using sodium alginate as an immobilising agent by slurry dipping technique. The average particle size and Polydispersity Index of drug conjugated gold NPs were found to be 129±2.35 nm and 0.243±0.36 respectively. Gold nanoparticles are characterized by UV-Vis absorption spectroscopy, Fourier Transform Infrared Spectroscopy (FT-IR), Scanning electron microscopy and Transmission electron microscopy. FT-IR revealed that there is no chemical interaction between drug and polymer. Antimicrobial activity for coated sutures was evaluated by disc diffusion method on culture plates of both gram negative (E-coli) and gram positive bacteria (Staphylococcus aureus) and results found to be satisfactory. In vivo studies for coated sutures was performed on Swiss albino mice and histological evaluation of intestinal wound healing parameters such as wound edges in mucosa, muscularis, presence of necrosis, exudates, granulation tissue, granulocytes, macrophages, restoration, and repair of mucosal epithelium and muscularis propria on day 7 after surgery were studied. The control animal group, sutured with plain suture (uncoated suture) showed signs of restoration and repair, but presence of necrosis, heamorraghic infiltration and granulation tissue was still noticed. Whereas the animal group treated with ciprofloxacin and ciprofloxacin gold nanoparticle coated sutures has shown promising decrease in terms of haemorraghic infiltration, granulation tissue, necrosis and better repaired muscularis layers on comparision with plain coated sutures indicating faster rate of repair and less chance of sepsis. Hence coating of sutures with broad spectrum antibiotics can be an alternate technique to reduce SSIs.

Keywords: ciprofloxacin hydrochloride, gold nanoparticles, surgical site infections, sutures

Procedia PDF Downloads 256
2747 Study on the Strength and Durability Properties of Ternary Blended Concrete

Authors: Athira Babu, M. Nazeer

Abstract:

Concrete is the most common and versatile construction material used in any type of civil engineering structure. The durability and strength characteristics of concrete make it more desirable among any other construction materials. The manufacture and use of concrete produces wide range of environmental and social consequences. The major component in concrete, cement accounts for roughly 5 % of global CO2 emissions. In order to improve the environmental friendliness of concrete, suitable substitutes are added to concrete. The present study deals with GGBS and silica fume as supplementary cementitious materials. The strength and durability studies were conducted in this ternary blended concrete. Several mixes were adopted with varying percentages of Silica Fume i.e., 5%, 10% and 15%. Binary mix with 50% GGBS was also prepared. GGBS content has been kept constant for the rest of mixes. There is an improvement in compressive strength with addition of Silica Fume.Maximum workability, split tensile strength, modulus of elasticity, flexural strength and impact resistance are obtained for GGBS binary blend. For durability studies, maximum sulphate resistance,carbonation resistance andresistance to chloride ion penetration are obtained for ternary blended concrete. Partial replacement of GGBS and Silica Fume reduces the environmental effects, produces economical and eco-friendly concrete. The study showed that for strength characteristics, binary blended concrete showed better performance while for durability study ternary blend performed better.

Keywords: concrete, GGBS, silica fume, ternary blend

Procedia PDF Downloads 482
2746 Contribution to the Study of the Rill Density Effects on Soil Erosion: Laboratory Experiments

Authors: L. Mouzai, M. Bouhadef

Abstract:

Rills begin to be generated once overland flow shear capacity overcomes the soil surface resistance. This resistance depends on soil texture, the arrangement of soil particles and on chemical and physical properties. The rill density could affect soil erosion, especially when the distance between the rills (interrill) contributes to the variation of the rill characteristics, and consequently on sediment concentration. To investigate this point, agricultural sandy soil, a soil tray of 0.2x1x3m³ and a piece of hardwood rectangular in shape to build up rills were the base of this work. The results have shown that small lines have been developed between the rills and the flow acceleration increased in comparison to the flow on the flat surface (interrill). Sediment concentration increased with increasing rill number (density).

Keywords: artificial rainfall, experiments, rills, soil erosion, transport capacity

Procedia PDF Downloads 164
2745 Drivers and Barriers for Implementing Environmental Management in Beverage Processors: A Case of Thailand

Authors: Auttasuriyanan Pakpoom, Setthasakko Watchaneeporn

Abstract:

The main purpose of this study is to gain a clearer understanding of key determinants that drive environmental management and barriers that hinder its development. The study employs semi-structured interviews with key informants accompanied by site observations. Key informants include production, environmental and plant managers of six beverage companies, including three Thai and three multinational companies in Thailand. It is found that corporate image, government subsidies, top management leadership and education institutes are four primary factors influencing the implementation of environmental management in the beverage processors. No demand from Asian buyers, employee resistance to change and lack of environmental knowledge are identified as barriers.

Keywords: environmental management, beverage, government subsidies, education institutes, employee resistance, environmental knowledge, Thailand

Procedia PDF Downloads 250
2744 Design, Analysis and Simulation of a Lightweight Fire-Resistant Door

Authors: Zainab Fadhil Al Toki, Nader Ghareeb

Abstract:

This study investigates how lightweight a fire resistance door will perform with under types of insulation materials. Data is initially collected from various websites, scientific books and research papers. Results show that different layers of insulation in a single door can perform better than one insulator. Furthermore, insulation materials that are lightweight, high strength and low thermal conductivity are the most preferred for fire-rated doors. Whereas heavy weight, low strength, and high thermal conductivity are least preferred for fire resistance doors. Fire-rated door specifications, theoretical test methodology, structural analysis, and comparison between five different models with diverse layers insulations are presented. Five different door models are being investigated with different insulation materials and arrangements. Model 1 contains an air gap between door layers. Model 2 includes phenolic foam, mild steel and polyurethane. Model 3 includes phenolic foam and glass wool. Model 4 includes polyurethane and glass wool. Model 5 includes only rock wool between the door layers. It is noticed that model 5 is the most efficient model, and its design is simple compared to other models. For this model, numerical calculations are performed to check its efficiency and the results are compared to data from experiments for validation. Good agreement was noticed.

Keywords: fire resistance, insulation, strength, thermal conductivity, lightweight, layers

Procedia PDF Downloads 51
2743 Hybrid Sol-Gel Coatings for Corrosion Protection of AA6111-T4 Aluminium Alloy

Authors: Shadatul Hanom Rashid, Xiaorong Zhou

Abstract:

Hybrid sol-gel coatings are the blend of both advantages of inorganic and organic networks have been reported as environmentally friendly anti-corrosion surface pre-treatment for several metals, including aluminum alloys. In this current study, Si-Zr hybrid sol-gel coatings were synthesized from (3-glycidoxypropyl)trimethoxysilane (GPTMS), tetraethyl orthosilicate (TEOS) and zirconium(IV) propoxide (TPOZ) precursors and applied on AA6111 aluminum alloy by dip coating technique. The hybrid sol-gel coatings doped with different concentrations of cerium nitrate (Ce(NO3)3) as a corrosion inhibitor were also prepared and the effect of Ce(NO3)3 concentrations on the morphology and corrosion resistance of the coatings were examined. The surface chemistry and morphology of the hybrid sol-gel coatings were analyzed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The corrosion behavior of the coated aluminum alloy samples was evaluated by electrochemical impedance spectroscopy (EIS). Results revealed that good corrosion resistance of hybrid sol-gel coatings were prepared from hydrolysis and condensation reactions of GPTMS, TEOS and TPOZ precursors deposited on AA6111 aluminum alloy. When the coating doped with cerium nitrate, the properties were improved significantly. The hybrid sol-gel coatings containing lower concentration of cerium nitrate offer the best inhibition performance. A proper doping concentration of Ce(NO3)3 can effectively improve the corrosion resistance of the alloy, while an excessive concentration of Ce(NO3)3 would reduce the corrosion protection properties, which is associated with defective morphology and instability of the sol-gel coatings.

Keywords: AA6111, Ce(NO3)3, corrosion, hybrid sol-gel coatings

Procedia PDF Downloads 158
2742 Bio-Genetic Activities Associated with Resistant in Peppers to Phytophthora capsici

Authors: Mehdi Nasr-Esfahani, Leila Mohammad Bagheri, Ava Nasr-Esfahani

Abstract:

Root and collar rot disease caused by Phytophthora capsici (Leonian) is one of the most serious diseases in pepper, Capsicum annuum L. In this study, a diverse collection of 37 commercial edible and ornamental pepper genotypes infected with P. capsici were investigated for biomass parameters and enzymatic activity of peroxidase or peroxide reductases (EC), superoxide dismutase (SOD), polyphenol oxidase (PPOs), catalase (CAT) and phenylalanine ammonia-lyase (PAL). Seven candidate DEG genes were also evaluated on resistant and susceptible pepper cultivars, through measuring product formation, using spectrophotometry and real-time polymerase chain reaction. All the five enzymes and seven defense-gene candidates were up-regulated in all inoculated pepper accessions to P. capsici. But, the enzymes and DEG genes were highly expressed in resistant cv. 19OrnP-PBI, 37ChillP-Paleo, and “23CherryP-Orsh". The expression level of enzymes were 1.5 to 5.6-fold higher in the resistant peppers, than the control non-inoculated genotypes. Also, the transcriptional levels of related candidate DEG genes were 3.16 to 5.90-fold higher in the resistant genotypes. There was a direct and high correlation coefficient between resistance, bio-mass parameters, enzymatic activity, and resistance gene expression. The related enzymes and candidate genes expressed herein will provide a basis for further gene cloning and functional verification studies, and also will aid in an understanding of the regulatory mechanism of pepper resistance to P. capsici.

Keywords: AP2/ERF, cDNA, enzymes, MIP gene, q-RTPCR, XLOC

Procedia PDF Downloads 152
2741 The Effect of Different Patterns of Upper, Lower and Whole Body Resistance Exercise Training on Systemic and Vascular Inflammatory Factors in Healthy Untrained Women

Authors: Leyla Sattarzadeh, Shahin Fathi Molk Kian, Maghsoud Peeri, Mohammadali Azarbaijani, Hasan Matin Homaee

Abstract:

Inflammation by various mechanisms may cause atherosclerosis. Systemic circulating inflammatory markers such as C-reactive protein (CRP), pro-inflammatory cytokines such as Interleukin-6 (IL-6), vascular inflammatory markers as adhesion molecules like Intracellular Adhesion Molecule-1 (ICAM-1) and Vascular Cell Adhesion Molecule-1 (VCAM-1) are the predictors of cardiovascular diseases. Regarding the conflicting results about the effect of different patterns of resistance exercise training on these inflammatory markers, present study aimed to examine the effect of different patterns of eight week resistance exercise training on CRP, IL-6, ICAM-1 and VCAM-1 levels in healthy untrained women. 56 healthy volunteered untrained female university students (aged: 21 ± 3 yr., Body Mass Index: 21.5 ± 3.5 kg/m²) were selected purposefully and divided into four groups. At the end of training protocol and after subject drop during the protocol, upper body exercise training (n=11), lower body (n=12) and whole body resistance exercise training group (n=11) completed the eight weeks of training period although the control group (n=7) did anything. Blood samples gathered pre and post-experimental period and CRP, IL-6, ICAM-1 and VCAM-1 levels were evaluated using special laboratory kits, then the difference of pre and post values of each indices analyzed using one-way analysis of variance (α < 0.05). The results of one way ANOVA for difference of pre and post values of CRP, ICAM-1 and VCAM-1 showed no significant changes due to the exercise training, but there were significant differences between groups about IL-6. Tukey post- hoc test indicated that there is significant difference between the differences of pre and post values of IL-6 between lower body exercise training group and control group, and eight weeks of lower body exercise training lead to significant changes in IL-6 values. There were no changes in anthropometric indices. The findings show that the different patterns of upper, lower and whole body exercise training by involving the different amounts of muscles altered the IL-6 values in lower body exercise training group probably because of engaging the bigger amount of muscles, but showed any significant changes about CRP, ICAM-1 and VCAM-1 probably due to intensity and duration of exercise or the lower levels of these markers at baseline of healthy people.

Keywords: resistance training, C-reactive protein, interleukin-6, intracellular adhesion molecule-1, vascular cell adhesion molecule-1

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2740 In vitro Antimicrobial Resistance Pattern of Bovine Mastitis Bacteria in Ethiopia

Authors: Befekadu Urga Wakayo

Abstract:

Introduction: Bacterial infections represent major human and animal health problems in Ethiopia. In the face of poor antibiotic regulatory mechanisms, development of antimicrobial resistance (AMR) to commonly used drugs has become a growing health and livelihood threat in the country. Monitoring and control of AMR demand close coloration between human and veterinary services as well as other relevant stakeholders. However, risk of AMR transfer from animal to human population’s remains poorly explored in Ethiopia. This systematic research literature review attempted to give an overview on AMR challenges of bovine mastitis bacteria in Ethiopia. Methodology: A web based research literature search and analysis strategy was used. Databases are considered including; PubMed, Google Scholar, Ethiopian Veterinary Association (EVA) and Ethiopian Society of Animal Production (ESAP). The key search terms and phrases were; Ethiopia, dairy, cattle, mastitis, bacteria isolation, antibiotic sensitivity and antimicrobial resistance. Ultimately, 15 research reports were used for the current analysis. Data extraction was performed using a structured Microsoft Excel format. Frequency AMR prevalence (%) was registered directly or calculated from reported values. Statistical analysis was performed on SPSS – 16. Variables were summarized by giving frequencies (n or %), Mean ± SE and demonstrative box plots. One way ANOVA and independent t test were used to evaluate variations in AMR prevalence estimates (Ln transformed). Statistical significance was determined at p < 0.050). Results: AMR in bovine mastitis bacteria was investigated in a total of 592 in vitro antibiotic sensitivity trials involving 12 different mastitis bacteria (including 1126 Gram positive and 77 Gram negative isolates) and 14 antibiotics. Bovine mastitis bacteria exhibited AMR to most of the antibiotics tested. Gentamycin had the lowest average AMR in both Gram positive (2%) and negative (1.8%) bacteria. Gram negative mastitis bacteria showed higher mean in vitro resistance levels to; Erythromycin (72.6%), Tetracycline (56.65%), Amoxicillin (49.6%), Ampicillin (47.6%), Clindamycin (47.2%) and Penicillin (40.6%). Among Gram positive mastitis bacteria higher mean in vitro resistance was observed in; Ampicillin (32.8%), Amoxicillin (32.6%), Penicillin (24.9%), Streptomycin (20.2%), Penicillinase Resistant Penicillin’s (15.4%) and Tetracycline (14.9%). More specifically, S. aurues exhibited high mean AMR against Penicillin (76.3%) and Ampicillin (70.3%) followed by Amoxicillin (45%), Streptomycin (40.6%), Tetracycline (24.5%) and Clindamycin (23.5%). E. coli showed high mean AMR to Erythromycin (78.7%), Tetracycline (51.5%), Ampicillin (49.25%), Amoxicillin (43.3%), Clindamycin (38.4%) and Penicillin (33.8%). Streptococcus spp. demonstrated higher (p =0.005) mean AMR against Kanamycin (> 20%) and full sensitivity (100%) to Clindamycin. Overall, mean Tetracycline (p = 0.013), Gentamycin (p = 0.001), Polymixin (p = 0.034), Erythromycin (p = 0.011) and Ampicillin (p = 0.009) resistance increased from the 2010’s than the 2000’s. Conclusion; the review indicated a rising AMR challenge among bovine mastitis bacteria in Ethiopia. Corresponding, public health implications demand a deeper, integrated investigation.

Keywords: antimicrobial resistance, dairy cattle, Ethiopia, Mastitis bacteria

Procedia PDF Downloads 245
2739 Aggregate Angularity on the Permanent Deformation Zones of Hot Mix Asphalt

Authors: Lee P. Leon, Raymond Charles

Abstract:

This paper presents a method of evaluating the effect of aggregate angularity on hot mix asphalt (HMA) properties and its relationship to the Permanent Deformation resistance. The research concluded that aggregate particle angularity had a significant effect on the Permanent Deformation performance, and also that with an increase in coarse aggregate angularity there was an increase in the resistance of mixes to Permanent Deformation. A comparison between the measured data and predictive data of permanent deformation predictive models showed the limits of existing prediction models. The numerical analysis described the permanent deformation zones and concluded that angularity has an effect of the onset of these zones. Prediction of permanent deformation help road agencies and by extension economists and engineers determine the best approach for maintenance, rehabilitation, and new construction works of the road infrastructure.

Keywords: aggregate angularity, asphalt concrete, permanent deformation, rutting prediction

Procedia PDF Downloads 405
2738 Changes in Skin Microbiome Diversity According to the Age of Xian Women

Authors: Hanbyul Kim, Hye-Jin Kin, Taehun Park, Woo Jun Sul, Susun An

Abstract:

Skin is the largest organ of the human body and can provide the diverse habitat for various microorganisms. The ecology of the skin surface selects distinctive sets of microorganisms and is influenced by both endogenous intrinsic factors and exogenous environmental factors. The diversity of the bacterial community in the skin also depends on multiple host factors: gender, age, health status, location. Among them, age-related changes in skin structure and function are attributable to combinations of endogenous intrinsic factors and exogenous environmental factors. Skin aging is characterized by a decrease in sweat, sebum and the immune functions thus resulting in significant alterations in skin surface physiology including pH, lipid composition, and sebum secretion. The present study gives a comprehensive clue on the variation of skin microbiota and the correlations between ages by analyzing and comparing the metagenome of skin microbiome using Next Generation Sequencing method. Skin bacterial diversity and composition were characterized and compared between two different age groups: younger (20 – 30y) and older (60 - 70y) Xian, Chinese women. A total of 73 healthy women meet two conditions: (I) living in Xian, China; (II) maintaining healthy skin status during the period of this study. Based on Ribosomal Database Project (RDP) database, skin samples of 73 participants were enclosed with ten most abundant genera: Chryseobacterium, Propionibacterium, Enhydrobacter, Staphylococcus and so on. Although these genera are the most predominant genus overall, each genus showed different proportion in each group. The most dominant genus, Chryseobacterium was more present relatively in Young group than in an old group. Similarly, Propionibacterium and Enhydrobacter occupied a higher proportion of skin bacterial composition of the young group. Staphylococcus, in contrast, inhabited more in the old group. The beta diversity that represents the ratio between regional and local species diversity showed significantly different between two age groups. Likewise, The Principal Coordinate Analysis (PCoA) values representing each phylogenetic distance in the two-dimensional framework using the OTU (Operational taxonomic unit) values of the samples also showed differences between the two groups. Thus, our data suggested that the composition and diversification of skin microbiomes in adult women were largely affected by chronological and physiological skin aging.

Keywords: next generation sequencing, age, Xian, skin microbiome

Procedia PDF Downloads 155
2737 Proposition Model of Micromechanical Damage to Predict Reduction in Stiffness of a Fatigued A-SMC Composite

Authors: Houssem Ayari

Abstract:

Sheet molding compounds (SMC) are high strength thermoset moulding materials reinforced with glass treated with thermocompression. SMC composites combine fibreglass resins and polyester/phenolic/vinyl and unsaturated acrylic to produce a high strength moulding compound. These materials are usually formulated to meet the performance requirements of the moulding part. In addition, the vinyl ester resins used in the new advanced SMC systems (A-SMC) have many desirable features, including mechanical properties comparable to epoxy, excellent chemical resistance and tensile resistance, and cost competitiveness. In this paper, a proposed model is used to take into account the Young modulus evolutions of advanced SMC systems (A-SMC) composite under fatigue tests. The proposed model and the used approach are in good agreement with the experimental results.

Keywords: composites SFRC, damage, fatigue, Mori-Tanaka

Procedia PDF Downloads 117