Search results for: no observed adverse effect level
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30748

Search results for: no observed adverse effect level

26428 Effect of Different Model Drugs on the Properties of Model Membranes from Fishes

Authors: M. Kumpugdee-Vollrath, T. G. D. Phu, M. Helmis

Abstract:

A suitable model membrane to study the pharmacological effect of pharmaceutical products is human stratum corneum because this layer of human skin is the outermost layer and it is an important barrier to be passed through. Other model membranes which were also used are for example skins from pig, mouse, reptile or fish. We are interested in fish skins in this project. The advantages of the fish skins are, that they can be obtained from the supermarket or fish shop. However, the fish skins should be freshly prepared and used directly without storage. In order to understand the effect of different model drugs e.g. lidocaine HCl, resveratrol, paracetamol, ibuprofen, acetyl salicylic acid on the properties of the model membrane from various types of fishes e.g. trout, salmon, cod, plaice permeation tests were performed and differential scanning calorimetry was applied.

Keywords: fish skin, model membrane, permeation, DSC, lidocaine HCl, resveratrol, paracetamol, ibuprofen, acetyl salicylic acid

Procedia PDF Downloads 471
26427 Study on the Stages of Knowledge Flow in Central Libraries of Tehran Universities by the Pattern of American Productivity & Quality Center

Authors: Amir Reza Asnafi, Ehsan Tajabadi, Mohsen Hajizeinolabedini

Abstract:

The purpose of this study is to identify the concept of knowledge flow in central libraries of Tehran universities in by the pattern of American Productivity & Quality Center (APQC). The present study is an applied and descriptive survey in terms of its purpose and the methodology used. In this study, APQC framework was used for data collection. The study population is managers and supervisors of central libraries’ departments of public universities of Tehran belonging to the Ministry of Science, Research and Technology. These libraries include: Central Libraries of Al-Zahra University, Amir Kabir, Tarbiat Modarres, Tehran, Khajeh Nasir Toosi University of Technology, Shahed, Sharif, Shahid Beheshti, Allameh Tabataba'i University, Iran University of Science and Technology. Due to the limited number of members of the community, sampling was not performed and the census was conducted instead. The study of knowledge flow in central libraries of public universities in Tehran showed that in seven dimensions of knowledge flow of APQC, these libraries are far from desirable level and to achieve the ideal point, many activities in the field of knowledge flow need to be made, therefore suggestions were made in this study to reach the desired level. One Sample t Test in this research showed that these libraries are at a poor level in terms of these factors: in the dimensions of creation, identification and use of knowledge at a medium level and in the aspects of knowledge acquisition, review, sharing and access and also Manova test or Multivariable Analyze of Variance proved that there was no significant difference between the dimensions of knowledge flow between these libraries and the status of the knowledge flow in these libraries is at the same level as well. Except for the knowledge creation aspect that is slightly different in this regard that was mentioned before.

Keywords: knowledge flow, knowledge management, APQC, Tehran’s academic university libraries

Procedia PDF Downloads 170
26426 The Necessity of Screening for Internalizing Mental Health Problems in Primary School Educational Settings

Authors: Atefeh Ahmadi, Mohamed Sharif Mustaffa

Abstract:

Mental health problems that children introspect them are hardly identified. The internalizing nature of Anxiety Disorders as the most prevalent psychological diseases, make them been under recognized by parents and teachers and so become under attended by school counsellors and subsequently under referred to clinicians. The aim of this study is to investigate the level of Anxiety Disorders to clarify if it is necessary to run screening programs in rural educational settings. Spence children anxiety scale-malay-child for the first time in Malaysia distributed among 640 Malay rural primary school students aged from 9-11 years old. Cut-off score was considered one standard deviation more than the mean of all students’ scores. The results of descriptive analyses revealed the mean for scores of SCAS was 32.84 and 15.6% of students had high level of anxiety. In addition, the level and prevalence of six types of anxiety disorders based on SCAS were described. In regards to the study outcomes, screening for anxiety disorders in academic settings could prevent and reduce their side effects by early identification.

Keywords: anxiety disorders, primary schools, SCAS, screening

Procedia PDF Downloads 304
26425 Experimental Investigations on the Mechanical properties of Spiny (Kawayan Tinik) Bamboo Layers

Authors: Ma. Doreen E. Candelaria, Ma. Louise Margaret A. Ramos, Dr. Jaime Y. Hernandez, Jr

Abstract:

Bamboo has been introduced as a possible alternative to some construction materials nowadays. Its potential use in the field of engineering, however, is still not widely practiced due to insufficient engineering knowledge on the material’s properties and characteristics. Although there are researches and studies proving its advantages, it is still not enough to say that bamboo can sustain and provide the strength and capacity required of common structures. In line with this, a more detailed analysis was made to observe the layered structure of the bamboo, particularly the species of Kawayan Tinik. It is the main intent of this research to provide the necessary experiments to determine the tensile strength of dried bamboo samples. The test includes tensile strength parallel to fibers with samples taken at internodes only. Throughout the experiment, methods suggested by the International Organization for Standardization (ISO) were followed. The specimens were tested using 3366 INSTRON Universal Testing Machine, with a rate of loading set to 0.6 mm/min. It was then observed from the results of these experiments that dried bamboo samples recorded high layered tensile strengths, as high as 600 MPa. Likewise, along the culm’s length and across its cross section, higher tensile strength were observed at the top part and at its outer layers. Overall, the top part recorded the highest tensile strength per layer, with its outer layers having tensile strength as high as 600 MPa. The recorded tensile strength of its middle and inner layers, on the other hand, were approximately 450 MPa and 180 MPa, respectively. From this variation in tensile strength across the cross section, it may be concluded that an increase in tensile strength may be observed towards the outer periphery of the bamboo. With these preliminary investigations on the layered tensile strength of bamboo, it is highly recommended to conduct experimental investigations on the layered compressive strength properties as well. It is also suggested to conduct investigations evaluating perpendicular layered tensile strength of the material.

Keywords: bamboo strength, layered strength tests, strength test, tensile test

Procedia PDF Downloads 425
26424 Electrical Properties of Roystonea regia Fruit Extract as Dye Sensitized Solar Cells

Authors: Adenike Boyo Olasunkanmi Kesinro, Henry Boyo, Surukite Oluwole

Abstract:

Utilizing solar energy in producing electricity can minimize environmental pollution generated by fossil fuel in producing electricity. Our research was base on the extraction of dye from Roystonea regia fruit by using methanol as solvent. The dye extracts were used as sensitizers in Dye-sensitized solar cell (DSSCs). Study was done on the electrical properties from the extracts of Roystonea regia fruit as Dye-sensitized solar cell (DSSCs). The absorptions of the extracts and extracts with dye were determined at different wavelengths (350-1000nm). Absorption peak was observed at 1.339 at wavelength 400nm. The obtained values for methanol extract Roystonea regia extract are, Imp = 0.015mA, Vmp = 12.0mV, fill factor = 0.763, Isc= 0.018 mA and Voc = 13.1 mV and efficiency of 0.32%. .The phytochemical screening was taken and it was observed that Roystonea regia extract contained less of anthocyanin compared to flavonoids. The nanostructured dye sensitized solar cell (DSSC) will provide economically credible alternative to present day silicon p–n junction photovoltaic.

Keywords: methanol, ethanol, titanium dioxide, roystonea regia fruit, dye-sensitized solar cell

Procedia PDF Downloads 405
26423 Study of Sustainability Practices Ingrained in Indian Culture

Authors: Shraddha Mahore Manjrekar

Abstract:

Culture has been an integral part of the civilizations in the world. Architectural works, in the material form of buildings, are often perceived as cultural symbols and as works of art. Historical civilizations are often identified with their surviving architectural achievements. Author has observed and thought about the relation of Indian traditional cultural beliefs and their relation to the sustainable environment. There are some unwritten norms regarding the use of resources and the environment in Indian continent, that have been commonly accepted by the people for building houses and settlements since the Vedic period . The research has been done on the chanting and prayers done in a number of houses and temples in Madhya Pradesh and Maharashtra. After doing some research, it was also found that resource assessment had also been done for the entire country, and an idea of conservation of these resources was imbibed in the common people by means of some traditions, customs and beliefs. The sensitization and gratefulness about natural resources have been observed in the major beliefs and customs. This paper describes few of such beliefs and customs that are directly linked with the built environment and landscape.

Keywords: Indian culture, sacred groves, sustainability in built environment, sustainability practices

Procedia PDF Downloads 298
26422 Piezotronic Effect on Electrical Characteristics of Zinc Oxide Varistors

Authors: Nadine Raidl, Benjamin Kaufmann, Michael Hofstätter, Peter Supancic

Abstract:

If polycrystalline ZnO is properly doped and sintered under very specific conditions, it shows unique electrical properties, which are indispensable for today’s electronic industries, where it is used as the number one overvoltage protection material. Under a critical voltage, the polycrystalline bulk exhibits high electrical resistance but becomes suddenly up to twelve magnitudes more conductive if this voltage limit is exceeded (i.e., varistor effect). It is known that these peerless properties have their origin in the grain boundaries of the material. Electric charge is accumulated in the boundaries, causing a depletion layer in their vicinity and forming potential barriers (so-called Double Schottky Barriers, or DSB) which are responsible for the highly non-linear conductivity. Since ZnO is a piezoelectric material, mechanical stresses induce polarisation charges that modify the DSB heights and as a result the global electrical characteristics (i.e., piezotronic effect). In this work, a finite element method was used to simulate emerging stresses on individual grains in the bulk. Besides, experimental efforts were made to testify a coherent model that could explain this influence. Electron back scattering diffraction was used to identify grain orientations. With the help of wet chemical etching, grain polarization was determined. Micro lock-in infrared thermography (MLIRT) was applied to detect current paths through the material, and a micro 4-point probes method system (M4PPS) was employed to investigate current-voltage characteristics between single grains. Bulk samples were tested under uniaxial pressure. It was found that the conductivity can increase by up to three orders of magnitude with increasing stress. Through in-situ MLIRT, it could be shown that this effect is caused by the activation of additional current paths in the material. Further, compressive tests were performed on miniaturized samples with grain paths containing solely one or two grain boundaries. The tests evinced both an increase of the conductivity, as observed for the bulk, as well as a decreased conductivity. This phenomenon has been predicted theoretically and can be explained by piezotronically induced surface charges that have an impact on the DSB at the grain boundaries. Depending on grain orientation and stress direction, DSB can be raised or lowered. Also, the experiments revealed that the conductivity within one single specimen can increase and decrease, depending on the current direction. This novel finding indicates the existence of asymmetric Double Schottky Barriers, which was furthermore proved by complementary methods. MLIRT studies showed that the intensity of heat generation within individual current paths is dependent on the direction of the stimulating current. M4PPS was used to study the relationship between the I-V characteristics of single grain boundaries and grain orientation and revealed asymmetric behavior for very specific orientation configurations. A new model for the Double Schottky Barrier, taking into account the natural asymmetry and explaining the experimental results, will be given.

Keywords: Asymmetric Double Schottky Barrier, piezotronic, varistor, zinc oxide

Procedia PDF Downloads 271
26421 Effect of Precursors Aging Time on the Photocatalytic Activity of Zno Thin Films

Authors: N. Kaneva, A. Bojinova, K. Papazova

Abstract:

Thin ZnO films are deposited on glass substrates via sol–gel method and dip-coating. The films are prepared from zinc acetate dehydrate as a starting reagent. After that the as-prepared ZnO sol is aged for different periods (0, 1, 3, 5, 10, 15, and 30 days). Nanocrystalline thin films are deposited from various sols. The effect ZnO sols aging time on the structural and photocatalytic properties of the films is studied. The films surface is studied by Scanning Electron Microscopy. The effect of the aging time of the starting solution is studied inrespect to photocatalytic degradation of Reactive Black 5 (RB5) by UV-vis spectroscopy. The experiments are conducted upon UV-light illumination and in complete darkness. The variation of the absorption spectra shows the degradation of RB5 dissolved in water, as a result of the reaction acurring on the surface of the films, and promoted by UV irradiation. The initial concentrations of dye (5, 10 and 20 ppm) and the effect of the aging time are varied during the experiments. The results show, that the increasing aging time of starting solution with respect to ZnO generally promotes photocatalytic activity. The thin films obtained from ZnO sol, which is aged 30 days have best photocatalytic degradation of the dye (97,22%) in comparison with the freshly prepared ones (65,92%). The samples and photocatalytic experimental results are reproducible. Nevertheless, all films exhibit a substantial activity in both UV light and darkness, which is promising for the development of new ZnO photocatalysts by sol-gel method.

Keywords: ZnO thin films, sol-gel, photocatalysis, aging time

Procedia PDF Downloads 384
26420 Factors Influencing Resolution of Anaphora with Collective Nominals in Russian

Authors: Anna Moskaleva

Abstract:

A prolific body of research in theoretical and experimental linguistics claims that a preference for conceptual or grammatical information in the process of agreement greatly depends on the type of agreement dependency. According to the agreement hierarchy, an anaphoric agreement is more sensitive to semantic or conceptual rather than grammatical information of an antecedent. Furthermore, a higher linear distance between a pronoun and its antecedent is assumed to trigger semantic agreement, yet the hierarchical distance is hardly examined in the research field, and the contribution of each distance factor is unclear. Apart from that, working memory volume is deemed to play a role in maintaining grammatical information during language comprehension. The aim of this study is to observe distance and working memory effects in resolution of anaphora with collective nominals (e.g., team) and to have a closer look at the interaction of the factors. Collective nominals in many languages can have a holistic or distributive meaning and can be addressed by a singular or a plural pronoun, respectively. We investigated linguistic factors of linear and rhetorical (hierarchical) distance and a more general factor of working memory volume in their ability to facilitate the interpretation of the number feature of a collective noun in Russian. An eye-tracking reading experiment on comprehension has been conducted where university students were presented with composed texts, including collective nouns and personal pronouns alluding to them. Different eye-tracking measures were calculated using statistical methods. The results have shown that a significant increase in reading time in the case of a singular pronoun was demonstrated when both distances were high, and no such effect was observed when just one of the distances was high. A decrease in reading time has been obtained with distance in the case of a plural pronoun. The working memory effect was not revealed in the experiment. The resonance of distance factors indicates that not only the linear distance but also the hierarchical distance is of great importance in interpreting pronouns. The experimental findings also suggest that, apart from the agreement hierarchy, the preference for conceptual or grammatical information correlates with the distance between a pronoun and its antecedent.

Keywords: collective nouns, agreement hierarchy, anaphora resolution, eye-tracking, language comprehension

Procedia PDF Downloads 43
26419 The Effect of Socialization Tactics on Job Satisfaction of Employees, Regarding to Personality Types in Tehran University of Medical Science’s Employees

Authors: Maryam Hoorzad, Narges Shokry, Mandan Momeni

Abstract:

According to importance of socialization in effectiveness of organizations and on the other hand assessing the impact of individual differences on socialization tactics by measuring employees satisfaction, can be assessed for each of the personality types which socialization tactics is the more effective. The aim of this paper is to investigate how organizational socialization tactics affect job satisfaction of employees according to personality types. A survey was conducted using a measurement tool based on Van Maanen and Schein’s theory on organizational socialization tactics and Myers Briggs’ measurement tools of personality types. The respondents were employees with more than 3 years backward in Tehran University of Medical Science. Data collection was performed using both library and field, the data collection instrument was questionnaires and data were analysed using the Spss and Lisrel programs. It was found that investiture and serial tactics has a significant effect on employees satisfaction, any increase in investiture and serial tactics led to increase in job satisfaction and any increase in divestiture and disjunctive tactics led to reduction of job satisfaction. Investiture tactic has the most effect on employees satisfaction. Also based on the results, personality types affect the relationship between socialization tactics and job satisfaction. In the ESFJ personality type the effect of investiture tactic on employee satisfaction is the most.

Keywords: organizational socialization, organizational socialization tactics, personality types, job satisfaction

Procedia PDF Downloads 444
26418 Investigation of Genetic Diversity of Tilia tomentosa Moench. (Silver Lime) in Duzce-Turkey

Authors: Ibrahim Ilker Ozyigit, Ertugrul Filiz, Seda Birbilener, Semsettin Kulac, Zeki Severoglu

Abstract:

In this study, we have performed genetic diversity analysis of Tilia tomentosa genotypes by using randomly amplified polymorphic DNA (RAPD) primers. A total of 28 genotypes, including 25 members from the urban ecosystem and 3 genotypes from forest ecosystem as outgroup were used. 8 RAPD primers produced a total of 53 bands, of which 48 (90.6 %) were polymorphic. Percentage of polymorphic loci (P), observed number of alleles (Na), effective number of alleles (Ne), Nei's (1973) gene diversity (h), and Shannon's information index (I) were found as 94.29 %, 1.94, 1.60, 0.34, and 0.50, respectively. The unweighted pair-group method with arithmetic average (UPGMA) cluster analysis revealed that two major groups were observed. The genotypes of urban and forest ecosystems showed a high genetic similarity between 28% and 92% and these genotypes did not separate from each other in UPGMA tree. Also, urban and forest genotypes clustered together in principal component analysis (PCA).

Keywords: Tilia tomentosa, genetic diversity, urban ecosystem, RAPD, UPGMA

Procedia PDF Downloads 514
26417 Estimation of Serum Levels of Calcium and Inorganic Phosphorus in Breast Cancer Patients

Authors: Safa Safdar

Abstract:

Breast cancer is a type of cancer which is developed by the formation of a tumor on the breast. This tumor invades and causes different electrolyte imbalance. The present study was designed to measure the serum calcium and inorganic phosphorous levels and to check the frequency of hypercalcemia and hypophosphatemia in breast cancer patients. Serum calcium and phosphorous levels of fifty breast cancer women of 18-70 years of age group and fifty healthy women of same age group were measured by using semi-automated chemistry analyzer ( Humalyzer 3000, Human, Germany ). Significant variation in these levels was observed. The mean calcium value in BC patients was higher 9.398 mg/dl as compared to controls which were 8.694 mg/dl. Whereas the mean value of inorganic phosphorus level was lower 4.060 mg/dl in BC patients as compared to controls having 4.456 mg/dl. In this study, the frequency of hypercalcemia in Breast cancer patients was 10% i.e. only 10 out of 50 Breast cancer patients were suffering from hypercalcemia. Whereas the frequency of hypophosphatemia in this study was only 2 % i.e. only 1 out of 50 patients was suffering from hypophosphatemia. Thus it is concluded that there is a significant change in serum calcium and inorganic phosphorous levels in Breast cancer patients as the disease progresses. So, this study will be helpful for the clinicians to maintain serum calcium and phosphorous levels in Breast cancer patients and also preventing them from further complications.

Keywords: serum analysis, calcium, inorganic phosphorus, hpercalcemia hypophosphatemia

Procedia PDF Downloads 296
26416 Estimation of Gaseous Pollutants at Kalyanpur, Dhaka City

Authors: Farhana Tarannum

Abstract:

Ambient (outdoor) air pollution is now recognized as an important problem, both nationally and worldwide. The concentrations of gaseous pollutants (SOx, NOx, CO and O3) have been determined from samples collected at Kallyanpur along Shamoli corridor in Dhaka city. Pollutants were determined in a sample collected at ground level and a roof of a 7-storied building. These pollutants are emitted largely from stationary sources like fossil fuel fired power plants, industrial plants, and manufacturing facilities as well as mobile sources. The incomplete combustion of fuel, wood and the Sulphur containing fuel used in the vehicles are one of the main causes of CO and SOx respectively in our natural environment. When the temperature of combustion in high enough and some of that nitrogen reacts with oxygen in the air, various nitrogen oxides (NOx) are then formed. The VOCs react with NOx in the presence of sunlight to form O3. UV Visible spectrophotometric method has been used for the determination of SOx, NOx and O3. The sensor type device was used for the estimation of CO. It was found that the air pollutants (CO, SOx, NOx and O3) of a sample collected at the roof of a building were lower compared to the ground level; it indicated that ground level people are mostly affected by the gaseous pollutants.

Keywords: gaseous pollutants, UV-visible spectrophotometry, ambient air quality, Dhaka city

Procedia PDF Downloads 352
26415 Entrepreneurial Intention and Social Entrepreneurship among Students in Malaysian Higher Education

Authors: Radin Siti Aishah Radin A Rahman, Norasmah Othman, Zaidatol Akmaliah Lope Pihie, Hariyaty Ab. Wahid

Abstract:

The recent instability in economy was found to be influencing the situation in Malaysia whether directly or indirectly. Taking that into consideration, the government needs to find the best approach to balance its citizen’s socio-economic strata level urgently. Through education platform is among the efforts planned and acted upon for the purpose of balancing the effects of the influence, through the exposure of social entrepreneurial activity towards youth especially those in higher institution level. Armed with knowledge and skills that they gained, with the support by entrepreneurial culture and environment while in campus; indirectly, the students will lean more on making social entrepreneurship as a career option when they graduate. Following the issues of marketability and workability of current graduates that are becoming dire, research involving how far the willingness of student to create social innovation that contribute to the society without focusing solely on personal gain is relevant enough to be conducted. With that, this research is conducted with the purpose of identifying the level of entrepreneurial intention and social entrepreneurship among higher institution students in Malaysia. Stratified random sampling involves 355 undergraduate students from five public universities had been made as research respondents and data were collected through surveys. The data was then analyzed descriptively using min score and standard deviation. The study found that the entrepreneurial intention of higher education students are on moderate level, however it is the contrary for social entrepreneurship activities, where it was shown on a high level. This means that while the students only have moderate level of willingness to be a social entrepreneur, they are very committed to created social innovation through the social entrepreneurship activities conducted. The implication from this study can be contributed towards the higher institution authorities in prediction the tendency of student in becoming social entrepreneurs. Thus, the opportunities and facilities for realizing the courses related to social entrepreneurship must be created expansively so that the vision of creating as many social entrepreneurs as possible can be achieved.

Keywords: entrepreneurial intention, higher education institutions (HEIs), social entrepreneurship, social entrepreneurial activity, gender

Procedia PDF Downloads 267
26414 Effect of Subsequent Drying and Wetting on the Small Strain Shear Modulus of Unsaturated Soils

Authors: A. Khosravi, S. Ghadirian, J. S. McCartney

Abstract:

Evaluation of the seismic-induced settlement of an unsaturated soil layer depends on several variables, among which the small strain shear modulus, Gmax, and soil’s state of stress have been demonstrated to be of particular significance. Recent interpretation of trends in Gmax revealed considerable effects of the degree of saturation and hydraulic hysteresis on the shear stiffness of soils in unsaturated states. Accordingly, the soil layer is expected to experience different settlement behaviors depending on the soil saturation and seasonal weathering conditions. In this study, a semi-empirical formulation was adapted to extend an existing Gmax model to infer hysteretic effects along different paths of the SWRC including scanning curves. The suitability of the proposed approach is validated against experimental results from a suction-controlled resonant column test and from data reported in literature. The model was observed to follow the experimental data along different paths of the SWRC, and showed a slight hysteresis in shear modulus along the scanning curves.

Keywords: hydraulic hysteresis, scanning path, small strain shear modulus, unsaturated soil

Procedia PDF Downloads 392
26413 Development of a Nurse Led Tranexamic Acid Administration Protocol for Trauma Patients in Rural South Africa

Authors: Christopher Wearmouth, Jacob Smith

Abstract:

Administration of tranexamic acid (TXA) reduces all-cause mortality in trauma patients when given within 3 hours of injury. Due to geographical distance and lack of emergency medical services patients often present late, following trauma, to our emergency department. Additionally, we found patients that may have benefited from TXA did not receive it, often due to lack of staff awareness, staff shortages out of hours and lack of equipment for delivering infusions. Our objective was to develop a protocol for nurse-led administration of TXA in the emergency department. We developed a protocol using physiological observations along with criteria from the South African Triage Scale to allow nursing staff to identify patients with, or at risk of, significant haemorrhage. We will monitor the use of the protocol to ensure appropriate compliance and for any adverse events reported.

Keywords: emergency department, emergency nursing, rural healthcare, tranexamic acid, trauma, triage

Procedia PDF Downloads 233
26412 Characterization of a Putative Type 1 Toxin-Antitoxin System in Shigella Flexneri

Authors: David Sarpong, Waleed Khursheed, Ernest Danquah, Erin Murphy

Abstract:

Shigella is a pathogenic bacterium responsible for shigellosis, a severe diarrheal disease that claims the lives of immunocompromised individuals worldwide. To develop therapeutics against this disease, an understanding of the molecular mechanisms underlying the pathogen’s physiology is crucial. Small non-coding RNAs (sRNAs) have emerged as important regulators of bacterial physiology, including as components of toxin-antitoxin systems. In this study, we investigated the role of RyfA in S. flexneri physiology and virulence. RyfA, originally identified as an sRNA in Escherichia coli, is conserved within the Enterobacteriaceae family, including Shigella. Whereas two copies of ryfA are present in S. dysenteriae, all other Shigella species contain only one copy of the gene. Additionally, we identified a putative open reading frame within the RyfA transcript, suggesting that it may be a dual-functioning gene encoding a small protein in addition to its sRNA function. To study ryfA in vitro, we cloned the gene into an inducible plasmid and observed the effect on bacterial growth. Here, we report that RyfA production inhibits the growth of S. flexneri, and this inhibition is dependent on the contained open reading frame. In-silico analyses have revealed the presence of two divergently transcribed sRNAs, RyfB1 and RyfB2, which share nucleotide complementarity with RyfA and thus are predicted to function as anti-toxins. Our data demonstrate that RyfB2 has a stronger antitoxin effect than RyfB1. This regulatory pattern suggests a novel form of a toxin-antitoxin system in which the activity of a single toxin is inhibited to varying degrees by two sRNA antitoxins. Studies are ongoing to investigate the regulatory mechanism(s) of the antitoxin genes, as well as the downstream targets and mechanism of growth inhibition by the RyfA toxin. This study offers distinct insights into the regulatory mechanisms underlying Shigella physiology and may inform the development of new anti-Shigella therapeutics.

Keywords: sRNA, shigella, toxin-antitoxin, Type 1 toxin antitoxin

Procedia PDF Downloads 55
26411 Plant Water Relations and Forage Quality in Leucaena leucocephala (Lam.) de Wit and Acacia saligna (Labill.) as Affected by Salinity Stress

Authors: Maher J. Tadros

Abstract:

This research was conducted to study the effect of different salinity concentrations on the plant water relation and forage quality on two multipurpose forest trees species seedlings Leucaena leucocephala (Lam.) de wit and Acacia saligna (Labill.). Five different salinity concentrations mixture between sodium chloride and calcium chloride (v/v, 1:1) were applied. The control (Distilled Water), 2000, 4000, 6000, and 8000 ppm were used to water the seedlings for 3 months. The research results presented showed a marked variation among the two species in response to salinity. The Leucaena was able to withstand the highest level of salinity compared to Acacia all over the studied parameters except in the relative water content. Although all the morphological characteristics studied for the two species showed a marked decrease under the different salinity concentrations, except the shoot/root ratio that showed a trend of increase. The water stress measure the leaf water potential was more negative with as the relative water content increase under that saline conditions compared to the control. The forage quality represented by the crude protein and nitrogen content were low at 6000 ppm compared to the 8000 ppm in L. Leucocephala that increased compared that level in A. saligna. Also the results showed that growing both Leucaena and Acacia provide a good source of forage when that grow under saline condition which will be of great benefits to the agricultural sector especially in the arid and semiarid areas were these species can provide forage with high quality forage all year around when grown under irrigation with saline. This research recommended such species to be utilized and grown for forages under saline conditions.

Keywords: plant water relations, growth performance, salinity stress, protein content, forage quality, multipurpose trees

Procedia PDF Downloads 396
26410 Electromagnetic Interference Shielding Characteristics for Stainless Wire Mesh and Number of Plies of Carbon Fiber Reinforced Plastic

Authors: Min Sang Lee, Hee Jae Shin, In Pyo Cha, Hyun Kyung Yoon, Seong Woo Hong, Min Jae Yu, Hong Gun Kim, Lee Ku Kwac

Abstract:

In this paper, the electromagnetic shielding characteristics of an up-to-date typical carbon filler material, carbon fiber used with a metal mesh were investigated. Carbon fiber 12k-prepregs, where carbon fibers were impregnated with epoxy, were laminated with wire meshes, vacuum bag-molded and hardened to manufacture hybrid-type specimens, with which an electromagnetic shield test was performed in accordance with ASTM D4935-10, through which was known as the most excellent reproducibility is obtainable among electromagnetic shield tests. In addition, glass fiber prepress whose electromagnetic shielding effect were known as insignificant were laminated and formed with wire meshes to verify the validity of the electromagnetic shield effect of wire meshes in order to confirm the electromagnetic shielding effect of metal meshes corresponding existing carbon fiber 12k-prepregs. By grafting carbon fibers, on which studies are being actively underway in the environmental aspects and electromagnetic shielding effect, with hybrid-type wire meshes that were analyzed through the tests, in this study, the applicability and possibility are proposed.

Keywords: Carbon Fiber Reinforced Plastic(CFRP), Glass Fiber Reinforced Plastic(GFRP), stainless wire mesh, electromagnetic shielding

Procedia PDF Downloads 420
26409 Robustified Asymmetric Logistic Regression Model for Global Fish Stock Assessment

Authors: Osamu Komori, Shinto Eguchi, Hiroshi Okamura, Momoko Ichinokawa

Abstract:

The long time-series data on population assessments are essential for global ecosystem assessment because the temporal change of biomass in such a database reflects the status of global ecosystem properly. However, the available assessment data usually have limited sample sizes and the ratio of populations with low abundance of biomass (collapsed) to those with high abundance (non-collapsed) is highly imbalanced. To allow for the imbalance and uncertainty involved in the ecological data, we propose a binary regression model with mixed effects for inferring ecosystem status through an asymmetric logistic model. In the estimation equation, we observe that the weights for the non-collapsed populations are relatively reduced, which in turn puts more importance on the small number of observations of collapsed populations. Moreover, we extend the asymmetric logistic regression model using propensity score to allow for the sample biases observed in the labeled and unlabeled datasets. It robustified the estimation procedure and improved the model fitting.

Keywords: double robust estimation, ecological binary data, mixed effect logistic regression model, propensity score

Procedia PDF Downloads 271
26408 The Hair Growth Effects of Undariopsis peterseniana

Authors: Jung-Il Kang, Jeon Eon Park, Yu-Jin Moon, Young-Seok Ahn, Eun-Sook Yoo, Hee-Kyoung Kang

Abstract:

This study was conducted to evaluate the effect of Undariopsis peterseniana, a seaweed native to Jeju Island, Korea, on the growth of hair. The dermal papilla cells (DPCs) have known to regulate hair growth cycle and length of hair follicle through interact with epithelial cells. When immortalized vibrissa DPCs were treated with the U. peterseniana extract, the U. peterseniana extract significantly increased the proliferation of DPCs. The effect of U. peterseniana extract on the growth of vibrissa follicles was also examined. U. peterseniana extract significantly increased the hair-fiber lengths of the vibrissa follicles. Hair loss is partly caused by dihydrotestosterone (DHT) binding to androgen receptor in hair follicles, and the inhibition of 5α-reductase activity can prevent hair loss through the decrease of DHT level. The U. peterseniana extract inhibited 5α-reductase activity. Minoxidil, a potent hair-growth agent, can induce proliferation in NIH3T3 fibroblasts by opening KATP channels. We thus examined the proliferative effects of U. peterseniana extract in NIH3T3 fibroblasts. U. peterseniana extract significantly increased the proliferation of NIH3T3 fibroblasts. Tetraethylammonium chloride (TEA), a K+ channel blocker, inhibited U. peterseniana-induced proliferation in NIH3T3 fibroblasts. These results suggest that U. peterseniana could have the potential to treat alopecia through the proliferation of DPCs, the inhibition of 5α-reductase activity and the opening of KATP channels. [Acknowledgement] This research was supported by The Leading Human Resource Training Program of Regional Neo industry through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT and future Planning (2016H1D5A1908786).

Keywords: hair growth, Undariopsis peterseniana, vibrissa follicles, dermal papilla cells, 5α-reductase, KATP channels

Procedia PDF Downloads 301
26407 Assessment of Genetic Variability of Potato Genotypes for Proline Under Salt Stress Conditions

Authors: Elchin Hajiyev, Afet Memmedova Dadash, Sabina Hajiyeva, Aynur Karimova, Ramiz Aliyev

Abstract:

Although potatoes have a wide distribution range, the yield potential of varieties varies greatly depending on the region. Our country is made up of agricultural regions with very different environmental characteristics.In this case, we cannot expect the introduced varieties to show the same adaptation to the different conditions of our country. For this reason, in our country, varieties with high general adaptability should be used, rather than varieties with special adaptability in certain areas. Soil salinization has become a global problem.Increased salinity has a serious impact on food security by reducing plant productivity. Plants have protective mechanisms of adaptation to salt stress, such as the synthesis of physiologically active substances, resistance to antioxidant stress and oxidation of membrane lipids. One of these substances is free proline. Our study revealed genetic variation in proline accumulation among samples exposed to stress factors.Changes in proline content under stress conditions were studied in 50 samples. There was wide variation across all treatments.The amount of proline varied between 7.2–37.7 μM/g under salinity conditions.The lowest rate was in the SF33 genotype (1.5 times more than the control (2.5 μM/g)).The highest level of proline under the influence of salt stress was in the SF45 genotype (7.25 times higher than the control (32.5 μM/g)). Our studies have found that the protective system reacts differently to the influence of stress factors. According to the results obtained on the amount of proline, adaptation mechanisms must be more actively activated to maintain metabolism and ensure viability in sensitive forms under the influence of stress factors. At high doses of the salt stressor, a tenfold increase in proline compared to the control indicates significant damage to the plant organism as a result of stress.To prevent damage to the body, the antioxidant system needs to quickly mobilize and work at full capacity in adverse conditions. An increase in the dose of the stress factor salt in our study caused a greater increase in the amount of free proline in plant tissues. Considering the functions of proline as an osmoprotector and antioxidant, it was found that increasing its amount is aimed at protecting the plant from the acute effects of stressors.

Keywords: genetic variability, potato, genotypes, proline, stress

Procedia PDF Downloads 58
26406 Liposome Loaded Polysaccharide Based Hydrogels: Promising Delayed Release Biomaterials

Authors: J. Desbrieres, M. Popa, C. Peptu, S. Bacaita

Abstract:

Because of their favorable properties (non-toxicity, biodegradability, mucoadhesivity etc.), polysaccharides were studied as biomaterials and as pharmaceutical excipients in drug formulations. These formulations may be produced in a wide variety of forms including hydrogels, hydrogel based particles (or capsules), films etc. In these formulations, the polysaccharide based materials are able to provide local delivery of loaded therapeutic agents but their delivery can be rapid and not easily time-controllable due to, particularly, the burst effect. This leads to a loss in drug efficiency and lifetime. To overcome the consequences of burst effect, systems involving liposomes incorporated into polysaccharide hydrogels may appear as a promising material in tissue engineering, regenerative medicine and drug loading systems. Liposomes are spherical self-closed structures, composed of curved lipid bilayers, which enclose part of the surrounding solvent into their structure. The simplicity of production, their biocompatibility, the size and similar composition of cells, the possibility of size adjustment for specific applications, the ability of hydrophilic or/and hydrophobic drug loading make them a revolutionary tool in nanomedicine and biomedical domain. Drug delivery systems were developed as hydrogels containing chitosan or carboxymethylcellulose (CMC) as polysaccharides and gelatin (GEL) as polypeptide, and phosphatidylcholine or phosphatidylcholine/cholesterol liposomes able to accurately control this delivery, without any burst effect. Hydrogels based on CMC were covalently crosslinked using glutaraldehyde, whereas chitosan based hydrogels were double crosslinked (ionically using sodium tripolyphosphate or sodium sulphate and covalently using glutaraldehyde). It has been proven that the liposome integrity is highly protected during the crosslinking procedure for the formation of the film network. Calcein was used as model active matter for delivery experiments. Multi-Lamellar vesicles (MLV) and Small Uni-Lamellar Vesicles (SUV) were prepared and compared. The liposomes are well distributed throughout the whole area of the film, and the vesicle distribution is equivalent (for both types of liposomes evaluated) on the film surface as well as deeper (100 microns) in the film matrix. An obvious decrease of the burst effect was observed in presence of liposomes as well as a uniform increase of calcein release that continues even at large time scales. Liposomes act as an extra barrier for calcein release. Systems containing MLVs release higher amounts of calcein compared to systems containing SUVs, although these liposomes are more stable in the matrix and diffuse with difficulty. This difference comes from the higher quantity of calcein present within the MLV in relation with their size. Modeling of release kinetics curves was performed and the release of hydrophilic drugs may be described by a multi-scale mechanism characterized by four distinct phases, each of them being characterized by a different kinetics model (Higuchi equation, Korsmeyer-Peppas model etc.). Knowledge of such models will be a very interesting tool for designing new formulations for tissue engineering, regenerative medicine and drug delivery systems.

Keywords: controlled and delayed release, hydrogels, liposomes, polysaccharides

Procedia PDF Downloads 230
26405 Evaluation of As-Cast U-Mo Alloys Processed in Graphite Crucible Coated with Boron Nitride

Authors: Kleiner Marques Marra, Tércio Pedrosa

Abstract:

This paper reports the production of uranium-molybdenum alloys, which have been considered promising fuel for test and research nuclear reactors. U-Mo alloys were produced in three molybdenum contents: 5 wt.%, 7 wt.%, and 10 wt.%, using an electric vacuum induction furnace. A boron nitride-coated graphite crucible was employed in the production of the alloys and, after melting, the material was immediately poured into a boron nitride-coated graphite mold. The incorporation of carbon was observed, but it happened in a lower intensity than in the case of the non-coated crucible/mold. It is observed that the carbon incorporation increased and alloys density decreased with Mo addition. It was also noticed that the increase in the carbon or molybdenum content did not seem to change the as-cast structure in terms of granulation. The three alloys presented body-centered cubic crystal structure (g phase), after solidification, besides a seeming negative microsegregation of molybdenum, from the center to the periphery of the grains. There were signs of macrosegregation, from the base to the top of the ingots.

Keywords: uranium-molybdenum alloys, incorporation of carbon, solidification, macrosegregation and microsegregation

Procedia PDF Downloads 155
26404 Coconut Shells as the Alternative Equipment for Foot Reflexology

Authors: Nichanant Sermsri, Chananchida Yuktirat

Abstract:

This research was the experimental research. Its purpose was to find out how coconut shells can be adapted to be equipment for foot and calf reflexology. The sample group was 58 female street vendors in Thewet Market, Dusit District, Bangkok, selected by selection criteria and voluntary. The data collecting tool in this research was the Visual Analogue Scale. The massaging tool made from coconut shells (designed and produced by the research team) was the key equipment for this research. The duration of the research was 1 month. The research team assessed the level of exhaustion and heart rate among sample group before and after the massage, then analyzed the data by mean, standard deviation and paired sample t-test. We found out from the research that 1) The level of exhaustion decreased 4.529 levels after the massage. The standard deviation was 1.6195. The heart rates went down 11.67 times/minute. The standard deviation was 6.742. 2) The level of exhaustion and heart rate after the massage decreased with the statistically significance at 0.01.

Keywords: foot reflexology, massaging plate, coconut shells, ecological sciences

Procedia PDF Downloads 188
26403 Occupational Safety in Construction Projects

Authors: Heba Elbibas, Esra Gnijeewa, Zedan Hatush

Abstract:

This paper presents research on occupational safety in construction projects, where the importance of safety management in projects was studied, including the preparation of a safety plan and program for each project and the identification of the responsibilities of each party to the contract. The research consists of two parts: 1-Field visits: which were field visits to three construction projects, including building projects, road projects, and tower installation. The safety level of these projects was evaluated through a checklist that includes the most important safety elements in terms of the application of these items in the projects. 2-Preparation of a questionnaire: which included supervisors and engineers and aimed to determine the level of awareness and commitment of different project categories to safety standards. The results showed the following: i) There is a moderate occupational safety policy. ii) The preparation and storage of maintenance reports are not fully complied with. iii) There is a moderate level of training on occupational safety for project workers. iv) The company does not impose penalties on safety violators permanently. v) There is a moderate policy for equipment and machinery safety. vi) Self-injuries occur due to (fatigue, lack of attention, deliberate error, and emotional factors), with a rate of 82.4%.

Keywords: management, safety, occupational safety, classification

Procedia PDF Downloads 112
26402 Structural, Magnetic and Electrical Properties of Gd3+ Doped CoFe2O4 Nanoparticles Synthesized by Sonochemical Method

Authors: Raghvendra Singh Yadav, Ivo Kuřitka

Abstract:

In this report, we studied the impact of Gd3+ substitution on structural, magnetic and electrical properties of CoFe2O4 nanoparticles synthesized by sonochemical method. X-ray diffraction pattern confirmed the formation of cubic spinel structure at low concentration of Gd3+ ions, however, GdFeO3 additional phase was observed at higher concentration of Gd3+ ions. Raman and Fourier Transform Infrared spectroscopy study also confirmed cubic spinel structure of Gd3+ substituted CoFe2O4 nanoparticles. The field emission scanning electron microscopy study revealed that Gd3+ substituted CoFe2O4 nanoparticles were in the range of 5-20 nm. The magnetic properties of Gd3+ substituted CoFe2O4 nanoparticles were investigated by using vibrating sample magnetometer. The variation in saturation magnetization, coercivity and remanent magnetization with Gd3+ concentration in CoFe2O4 nanoparticles was observed. The variation of real and imaginary part of dielectric constant, tan δ, and AC conductivity were studied at room temperature.

Keywords: spinel ferrites, nanoparticles, sonochemical method, magnetic properties

Procedia PDF Downloads 300
26401 Plasma Electrolytes and Gamma Glutamyl Transpeptidase (GGT) Status in Dementia Subjects in Southern Nigeria

Authors: Salaam Mujeeb, Adeola Segun, Abdullahi Olasunkanmi

Abstract:

Dementia is becoming a major concern as the world population is increasing and elderly populations are being neglected. Liver and kidney Diseases have been implicated as risk factors in the etiology of Dementia. This study, therefore, evaluates the plasma Gamma Glutamyl Transferase (GGT) activity and plasma Electrolytes in other to find an association between the biomarkers and Dementia. The subjects (38) were age and sex-matched with their corresponding controls and structured questionnaires were used to obtain medical information. Using spectrophotometric and ion selective Electrode techniques respectively, we found and elevated GGT activity in the Dementia Subjects. Remarkably, no association was found between the plasma Electrolytes level and Dementia subjects. It was also observed that severity of Dementia worsens with age. Moreover, the condition of the dementia subjects worsens with reducing weight. Furthermore, the presence of Comorbidity e.g. Hypertension, Obesity, Diabetes and Habits like Smoking, Drugs and Alcohol consumption interferes with Electrolyte balance. Weight loss monitoring and IBM check are advised in Elderly individuals particularly females as they may be inductive of early or future cognitive impairments. Therefore, it might be useful as an early detection tool. Government and society should invest more on the Geriatric population by establishing Old people's home and providing social care services.

Keywords: clinical characteristics, dementia, electrolytes, gamma glutamyl transpeptidase, GGT

Procedia PDF Downloads 333
26400 Lactic Acid Solution and Aromatic Vinegar Nebulization to Improve Hunted Wild Boar Carcass Hygiene at Game-Handling Establishment: Preliminary Results

Authors: Rossana Roila, Raffaella Branciari, Lorenzo Cardinali, David Ranucci

Abstract:

The wild boar (Sus scrofa) population has strongly increased across Europe in the last decades, also causing severe fauna management issues. In central Italy, wild boar is the main hunted wild game species, with approximately 40,000 animals killed per year only in the Umbria region. The meat of the game is characterized by high-quality nutritional value as well as peculiar taste and aroma, largely appreciated by consumers. This type of meat and products thereof can meet the current consumers’ demand for higher quality foodstuff, not only from a nutritional and sensory point of view but also in relation to environmental sustainability, the non-use of chemicals, and animal welfare. The game meat production chain is characterized by some gaps from a hygienic point of view: the harvest process is usually conducted in a wild environment where animals can be more easily contaminated during hunting and subsequent practices. The definition and implementation of a certified and controlled supply chain could ensure quality, traceability and safety for the final consumer and therefore promote game meat products. According to European legislation in some animal species, such as bovine, the use of weak acid solutions for carcass decontamination is envisaged in order to ensure the maintenance of optimal hygienic characteristics. A preliminary study was carried out to evaluate the applicability of similar strategies to control the hygienic level of wild boar carcasses. The carcasses, harvested according to the selective method and processed into the game-handling establishment, were treated by nebulization with two different solutions: a 2% food-grade lactic acid solution and aromatic vinegar. Swab samples were performed before treatment and in different moments after-treatment of the carcasses surfaces and subsequently tested for Total Aerobic Mesophilic Load, Total Aerobic Psychrophilic Load, Enterobacteriaceae, Staphylococcus spp. and lactic acid bacteria. The results obtained for the targeted microbial populations showed a positive effect of the application of the lactic acid solution on all the populations investigated, while aromatic vinegar showed a lower effect on bacterial growth. This study could lay the foundations for the optimization of the use of a lactic acid solution to treat wild boar carcasses aiming to guarantee good hygienic level and safety of meat.

Keywords: game meat, food safety, process hygiene criteria, microbial population, microbial growth, food control

Procedia PDF Downloads 162
26399 Momentum Profits and Investor Behavior

Authors: Aditya Sharma

Abstract:

Profits earned from relative strength strategy of zero-cost portfolio i.e. taking long position in winner stocks and short position in loser stocks from recent past are termed as momentum profits. In recent times, there has been lot of controversy and concern about sources of momentum profits, since the existence of these profits acts as an evidence of earning non-normal returns from publicly available information directly contradicting Efficient Market Hypothesis. Literature review reveals conflicting theories and differing evidences on sources of momentum profits. This paper aims at re-examining the sources of momentum profits in Indian capital markets. The study focuses on assessing the effect of fundamental as well as behavioral sources in order to understand the role of investor behavior in stock returns and suggest (if any) improvements to existing behavioral asset pricing models. This Paper adopts calendar time methodology to calculate momentum profits for 6 different strategies with and without skipping a month between ranking and holding period. For each J/K strategy, under this methodology, at the beginning of each month t stocks are ranked on past j month’s average returns and sorted in descending order. Stocks in upper decile are termed winners and bottom decile as losers. After ranking long and short positions are taken in winner and loser stocks respectively and both portfolios are held for next k months, in such manner that at any given point of time we have K overlapping long and short portfolios each, ranked from t-1 month to t-K month. At the end of period, returns of both long and short portfolios are calculated by taking equally weighted average across all months. Long minus short returns (LMS) are momentum profits for each strategy. Post testing for momentum profits, to study the role market risk plays in momentum profits, CAPM and Fama French three factor model adjusted LMS returns are calculated. In the final phase of studying sources, decomposing methodology has been used for breaking up the profits into unconditional means, serial correlations, and cross-serial correlations. This methodology is unbiased, can be used with the decile-based methodology and helps to test the effect of behavioral and fundamental sources altogether. From all the analysis, it was found that momentum profits do exist in Indian capital markets with market risk playing little role in defining them. Also, it was observed that though momentum profits have multiple sources (risk, serial correlations, and cross-serial correlations), cross-serial correlations plays a major role in defining these profits. The study revealed that momentum profits do have multiple sources however, cross-serial correlations i.e. the effect of returns of other stocks play a major role. This means that in addition to studying the investors` reactions to the information of the same firm it is also important to study how they react to the information of other firms. The analysis confirms that investor behavior does play an important role in stock returns and incorporating both the aspects of investors’ reactions in behavioral asset pricing models help make then better.

Keywords: investor behavior, momentum effect, sources of momentum, stock returns

Procedia PDF Downloads 308