Search results for: adult stem cells
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4925

Search results for: adult stem cells

1685 Complex Dynamics in a Morphologically Heterogeneous Biological Medium

Authors: Turky Al-Qahtani, Roustem Miftahof

Abstract:

Introduction: Under common assumptions of excitabi-lity, morphological (cellular) homogeneity, and spatial structural anomalies added as required, it has been shown that biological systems are able to display travelling wave dynamics. Being not self-sustainable, existence depends on the electrophysiological state of transmembrane ion channels and it requires an extrinsic/intrinsic periodic source. However, organs in the body are highly multicellular, heterogeneous, and their functionality is the outcome of electro-mechanical conjugation, rather than excitability only. Thus, peristalsis in the gut relies on spatiotemporal myoelectrical pattern formations between the mechanical, represented by smooth muscle cells (SM), and the control, comprised of a chain of primary sensory and motor neurones, components. Synaptically linked through the afferent and efferent pathways, they form a functional unit (FU) of the gut. Aims: These are: i) to study numerically the complex dynamics, and ii) to investigate the possibility of self-sustained myoelectrical activity in the FU. Methods: The FU recreates the following sequence of physiological events: deformation of mechanoreceptors of located in SM; generation and propagation of electrical waves of depolarisation - spikes - along the axon to the soma of the primary neurone; discharge of the primary neurone and spike propagation towards the motor neurone; burst of the motor neurone and transduction of spikes to SM, subsequently producing forces of contraction. These are governed by a system of nonlinear partial and ordinary differential equations being a modified version of the Hodgkin-Huxley model and SM fibre mechanics. In numerical experiments; the source of excitation is mechanical stretches of SM at a fixed amplitude and variable frequencies. Results: Low frequency (0.5 < v < 2 Hz) stimuli cause the propagation of spikes in the neuronal chain and, finally, the generation of active forces by SM. However, induced contractions are not sufficient to initiate travelling wave dynamics in the control system. At frequencies, 2 < v < 4 Hz, multiple low amplitude and short-lasting contractions are observed in SM after the termination of stretching. For frequencies (0.5 < v < 4 Hz), primary and sensory neurones demonstrate strong connectivity and coherent electrical activity. Significant qualitative and quantitative changes in dynamics of myoelectical patterns with a transition to a self-organised mode are recorded with the high degree of stretches at v = 4.5 Hz. Increased rates of deformation lead to the production of high amplitude signals at the mechanoreceptors with subsequent self-sustained excitation within the neuronal chain. Remarkably, the connection between neurones weakens resulting in incoherent firing. Further increase in a frequency of stimulation (v > 4.5 Hz) has a detrimental effect on the system. The mechanical and control systems become disconnected and exhibit uncoordinated electromechanical activity. Conclusion: To our knowledge, the existence of periodic activity in a multicellular, functionally heterogeneous biological system with mechano-electrical dynamics, such as the FU, has been demonstrated for the first time. These findings support the notion of possible peristalsis in the gut even in the absence of intrinsic sources - pacemaker cells. Results could be implicated in the pathogenesis of intestinal dysrythmia, a medical condition associated with motor dysfunction.

Keywords: complex dynamics, functional unit, the gut, dysrythmia

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1684 Liminal Disabled Tweens’ Identification with Disney Animations in Algeria

Authors: Selma Aitsaid

Abstract:

Disney canon texts, mainly animations, are believed to have authority over children’s identities. However, most research on Disney tends to focus either on textual analysis, or Western and non-western adult audiences. In fact, there is a lack of scholarship on Disney child audiences from non-western countries though children are believed to be Disney‘s main target audience, and Disney is a global corporation that appeals to audiences from all over the world as well. Therefore, qualitative research was conducted by interviewing around twenty five Algerian disabled tweens between the age 11 to 14 on their familiarity and identification with Disney animations. The reason behind choosing disabled children is because minority groups have not been interviewed on their possible interpretations of Disney animations despite the fact that these texts have been interpreted by some scholars as being inclusive of minority groups such as queer and disabled people. To that end, this project aims to decolonize disability and Global Southern Academia by three ways. The first way is to uncover inequalities of the metropolitan thought enshrined in the global power of the metropole vis a vis the subaltern. This approach was called postcolonialism. The second way is to value non-western academic and non-academic resources. This is the project of ‘indigenous knowledge. The third way is to analyse the forms of knowledge that were produced by intellectuals in colonized countries as a response to Western Academic hegemony. Consequently, this research endeavored to unravel the inequality, the dynamics of neocolonialism and subordination to colonial discourses within the Algerian discourse on disability and other knowledge such as tweenhood, childhood and non-western viewership, which are mainly defined through Western lenses. Algerian resources were included with the aim of enhancing an academic collaboration between the North and South as well. The findings showed that the postcolonial context had an impact on how children perceive Disney animations. They also demonstrated that children are able to negotiate the meaning of Disney texts within their own context.

Keywords: child audiences, Algeria, childhood, disability, Disney animations, global South, postcolonialism, tweens, Western hegemony

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1683 Physiological Responses of Dominant Grassland Species to Different Grazing Intensity in Inner Mongolia, China

Authors: Min Liu, Jirui Gong, Qinpu Luo, Lili Yang, Bo Yang, Zihe Zhang, Yan Pan, Zhanwei Zhai

Abstract:

Grazing disturbance is one of the important land-use types that affect plant growth and ecosystem processes. In order to study the responses of dominant species to grazing in the semiarid temperate grassland of Inner Mongolia, we set five grazing intensity plots: a control and four levels of grazing (light (LG), moderate (MG), heavy (HG) and extreme heavy grazing (EHG)) to test the morphological and physiological responses of Stipa grandis, Leymus chinensis at the individual levels. With the increase of grazing intensity, Stipa grandis and Leymus chinensis both exhibited reduced plant height, leaf area, stem length and aboveground biomass, showing a significant dwarf phenomenon especially in HG and EHG plots. The photosynthetic capacity decreased along the grazing gradient. Especially in the MG plot, the two dominant species have lowest net photosynthetic rate (Pn) and water use efficiency (WUE). However, in the HG and EHG plots, the two species had high light saturation point (LSP) and low light compensation point (LCP), indicating they have high light-use efficiency. They showed a stimulation of compensatory photosynthesis to the remnant leaves as compared with grasses in MG plot. For Leymus chinensis, the lipid peroxidation level did not increase with the low malondialdehyde (MDA) content even in the EHG plot. It may be due to the high enzymes activity of superoxide dismutase (SOD) and peroxidase (POD) to reduce the damage of reactive oxygen species. Meanwhile, more carbohydrate was stored in the leaf of Leymus chinensis to provide energy to the plant regrowth. On the contrary, Stipa grandis showed the high level of lipid peroxidation especially in the HG and EHG plots with decreased antioxidant enzymes activity. The soluble protein content did not change significantly in the different plots. Therefore, with the increase of grazing intensity, plants changed morphological and physiological traits to defend themselves effectively to herbivores. Leymus chinensis is more resistant to grazing than Stipa grandis in terms of tolerance traits, particularly under heavy grazing pressure.

Keywords: antioxidant enzymes activity, grazing density, morphological responses, photosynthesis

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1682 High-Throughput Screening and Selection of Electrogenic Microbial Communities Using Single Chamber Microbial Fuel Cells Based on 96-Well Plate Array

Authors: Lukasz Szydlowski, Jiri Ehlich, Igor Goryanin

Abstract:

We demonstrate a single chamber, 96-well-plated based Microbial Fuel Cell (MFC) with printed, electronic components. This invention is aimed at robust selection of electrogenic microbial community under specific conditions, e.g., electrode potential, pH, nutrient concentration, salt concentration that can be altered within the 96 well plate array. This invention enables robust selection of electrogenic microbial community under the homogeneous reactor, with multiple conditions that can be altered to allow comparative analysis. It can be used as a standalone technique or in conjunction with other selective processes, e.g., flow cytometry, microfluidic-based dielectrophoretic trapping. Mobile conductive elements, like carbon paper, carbon sponge, activated charcoal granules, metal mesh, can be inserted inside to increase the anode surface area in order to collect electrogenic microorganisms and to transfer them into new reactors or for other analytical works. An array of 96-well plate allows this device to be operated by automated pipetting stations.

Keywords: bioengineering, electrochemistry, electromicrobiology, microbial fuel cell

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1681 The Training Demands of Nursing Assistants on Urinary Incontinence in Nursing Homes: A Mixed Methods Study

Authors: Lulu Liao, Huijing Chen, Yinan Zhao, Hongting Ning, Hui Feng

Abstract:

Urinary tract infection rate is an important index of care quality in nursing homes. The aim of the study is to understand the nursing assistant's current knowledge and attitudes of urinary incontinence and to explore related stakeholders' viewpoint about urinary incontinence training. This explanatory sequential study used Knowledge, Practice, and Attitude Model (KAP) and Adult Learning Theories, as the conceptual framework. The researchers collected data from 509 nursing assistants in sixteen nursing homes in Hunan province in China. The questionnaire survey was to assess the knowledge and attitude of urinary incontinence of nursing assistants. On the basis of quantitative research and combined with focus group, training demands were identified, which nurse managers should adopt to improve nursing assistants’ professional practice ability in urinary incontinence. Most nursing assistants held the poor knowledge (14.0 ± 4.18) but had positive attitudes (35.5 ± 3.19) toward urinary incontinence. There was a significant positive correlation between urinary incontinence knowledge and nursing assistants' year of work and educational level, urinary incontinence attitude, and education level (p < 0.001). Despite a general awareness of the importance of prevention of urinary tract infections, not all nurse managers fully valued the training in urinary incontinence compared with daily care training. And the nursing assistants required simple education resources to equip them with skills to address problem about urinary incontinence. The variety of learning methods also highlighted the need for educational materials, and nursing assistants had shown a strong interest in online learning. Related education material should be developed to meet the learning need of nurse assistants and provide suitable training method for planned quality improvement in urinary incontinence.

Keywords: mixed methods, nursing assistants, nursing homes, urinary incontinence

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1680 Improvement of Bearing Capacity of Soft Clay Using Geo-Cells

Authors: Siddhartha Paul, Aman Harlalka, Ashim K. Dey

Abstract:

Soft clayey soil possesses poor bearing capacity and high compressibility because of which foundations cannot be directly placed over soft clay. Normally pile foundations are constructed to carry the load through the soft soil up to the hard stratum below. Pile construction is costly and time consuming. In order to increase the properties of soft clay, many ground improvement techniques like stone column, preloading with and without sand drains/band drains, etc. are in vogue. Time is a constraint for successful application of these improvement techniques. Another way to improve the bearing capacity of soft clay and to reduce the settlement possibility is to apply geocells below the foundation. The geocells impart rigidity to the foundation soil, reduce the net load intensity on soil and thus reduce the compressibility. A well designed geocell reinforced soil may replace the pile foundation. The present paper deals with the applicability of geocells on improvement of the bearing capacity. It is observed that a properly designed geocell may increase the bearing capacity of soft clay up to two and a half times.

Keywords: bearing capacity, geo-cell, ground improvement, soft clay

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1679 Xanthotoxin: A Plant Derived Furanocoumarin with Antipathogenic and Cytotoxic Activities

Authors: Seyed Mehdi Razavi Khosroshahi

Abstract:

In recent years a great deal of efforts has been made to find natural derivative compounds to replace it's with synthetic drugs, herbicides or pesticides for management of human health and agroecosystem programs. This process can lead to a reduction in environmental harmful effects of synthetic chemicals. Xanthotoxin, as a furanocoumarin compound, found in some genera of the Apiaceae family of plants. The current work focuses on some xanthotoxin cytotoxicity and antipathogenic activities. The results indicated that xanthotoxin showed strong cytotoxic effects against LNCaP cell line with the IC₅₀ value of 0.207 mg/ml in a dose-dependent manner. After treatments of the cell line with 0.1 mg/ml of the compound, the viability of the cells was reached to zero. The current study revealed that xanthotoxin displayed strong antifungal activity against human or plant pathogen fungi, Aspergillus fumigatus, Aspegillusn flavus and Fusarum graminearum with minimum inhibitory concentration values of 52-68 µg/ml. The compound exhibited antibacterial effects on some Erwinia and Xanthomonas species of bacteria, as well

Keywords: Xanthomonas, cytotoxic, antipathogen, LNCaP, Aspergillus fumigatus, spegillusn flavus

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1678 Market Chain Analysis of Onion: The Case of Northern Ethiopia

Authors: Belayneh Yohannes

Abstract:

In Ethiopia, onion production is increasing from time to time mainly due to its high profitability per unit area. Onion has a significant contribution to generating cash income for farmers in the Raya Azebo district. Therefore, enhancing onion producers’ access to the market and improving market linkage is an essential issue. Hence, this study aimed to analyze structure-conduct-performance of onion market and identifying factors affecting the market supply of onion producers. Data were collected from both primary and secondary sources. Primary data were collected from 150 farm households and 20 traders. Four onion marketing channels were identified in the study area. The highest total gross margin is 27.6 in channel IV. The highest gross marketing margin of producers of the onion market is 88% in channel II. The result from the analysis of market concentration indicated that the onion market is characterized by a strong oligopolistic market structure, with the buyers’ concentration ratio of 88.7 in Maichew town and 82.7 in Mekelle town. Lack of capital, licensing problems, and seasonal supply was identified as the major entry barrier to onion marketing. Market conduct shows that the price of onion is set by traders while producers are price takers. Multiple linear regression model results indicated that family size in adult equivalent, irrigated land size, access to information, frequency of extension contact, and ownership of transport significantly determined the quantity of onion supplied to the market. It is recommended that strengthening and diversifying extension services in information, marketing, post-harvest handling, irrigation application, and water harvest technology is highly important.

Keywords: oligopoly, onion, market chain, multiple linear regression

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1677 Anti-Ulcer Activity of Hydro Alcoholic Extract of Ficus bengalensis Linn Bark in Experimental Rats

Authors: Jagdish Baheti, Sampat Navale

Abstract:

The present study was performed to evaluate the anti-ulcerogenic activity of hydro-alcoholic extract of Ficus bengalensis Linn. against ethanol-induced gastric mucosal injury in rats and pylorus ligation gastric secretion in rats. Five groups of adult wistar rats were orally pre-treated respectively with carboxy methyl cellulose (CMC) solution (ulcer control group), Omeprazole 20 mg/kg (reference group), and 100, 200 and 300 mg/kg F. bengalensis Linn. bark extract in CMC solution (experimental groups), one hour before oral administration of absolute ethanol to generate gastric mucosal injury. Rats were sacrificed and the ulcer index, gastric volume, gastric pH, free acidity, total acidity of the gastric content was determined. Grossly, the ulcer control group exhibited severe mucosal injury, whereas pre-treatment with F. bengalensis Linn. bark extract exhibited significant protection of gastric mucosal injury in both model. Histological studies revealed that ulcer control group exhibited severe damage of gastric mucosa, along with edema and leucocytes infiltration of submucosal layer compared to rats pre-treated with F. bengalensis Linn. bark extract which showed gastric mucosal protection, reduction or absence of edema and leucocytes infiltration of submucosal layer. Acute toxicity study did not manifest any toxicological signs in rats. The present finding suggests that F. bengalensis Linn. bark extract promotes ulcer protection as ascertained grossly and histologically compared to the ulcer control group.

Keywords: Ficus bengalensis Linn., gastric ulcer, hydroalcoholic, pylorus ligation

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1676 Prevalence and Spatial Distribution of Anaemia in Ethiopia using 2011 EDHS

Authors: Bedilu A. Ejigu, Eshetu Wencheko, Kiros Berhane

Abstract:

Anaemia is a condition in which the haemoglobin concentration falls below an established cut-off value due to a decrease in the number and size of red blood cells. The current study aimed to assess the spatial pattern and identify predictors related to anaemia using the third Ethiopian demographic health survey which was conducted in 2010. To achieve this objective, this study took into account the clustered nature of the data. As a result, multilevel modeling has been used in the statistical analysis. For analysis purpose, only complete cases from 15,909 females, and 13,903 males were considered. Among all subjects who agreed for haemoglobin test, 5.49 %males, and 19.86% females were anaemic. In both binary and ordinal outcome modeling approaches, educational level, age, wealth index, BMI and HIV status were identified to be significant predictors for anaemia prevalence. Furthermore, it was noted that pregnant women were more anaemic than non-pregnant women. As revealed by Moran's I test, significant spatial autocorrelation was noted across clusters. The risk of anaemia was found to vary across different regions, and higher prevalence was observed in Somali and Affar region.

Keywords: anaemia, Moran's I test, multilevel models, spatial pattern

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1675 Effect of Perioperative Protocol of Care on Clinical Outcomes among Patients Undergoing Coronary Artery Bypass Graft

Authors: Manal Ahmed, Amal Shehata, Shereen Deeb

Abstract:

The study's purpose was to determine the effect of the perioperative protocol of care on clinical outcomes among patients undergoing coronary artery bypass graft. Subjects: A sample of 100 adult patients who were planned for coronary artery bypass graft, were selected and divided alternatively and randomly into two equal groups (50 study -50 control).The study was carried out at National heart Institute in Cairo and open heart surgical intensive care unit in Shebin El-Kom Teaching Hospital. Instruments: Four instruments were used for data collection: Interviewing questionnaire, dyspnea analogue scale, Biophysiological measurement instrument, and Compliance assessment sheet. Results: There were statistically significant differences between both groups regarding most respiratory system assessment findings at discharge. More than two-thirds of the study group of the current study had a continuous and regular commitment to diet regimen, which ranked first followed by the compliance of daily living activities then quitting smoking. Conclusions: The perioperative protocol of care has a significant improving effect on respiratory findings, dyspnea degree, duration of mechanical ventilation, length of hospital stay, compliance to diet, therapeutic regimen, daily living activities, and quit smoking among study group undergoing CABG. Recommendations: Perioperative protocol of care should be carried out for CABG patients at open-heart surgical units as well as an illustrative colored booklet about CAD, CABG and perioperative care should be available and distributed to all CABG patients.

Keywords: perioperative, effect, clinical outcomes, coronary artery, bypass graft, protocol of care

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1674 Reversal of Testicular Damage and Subfertility by Resveratrol

Authors: Samy S. Eleawa, Mahmoud A. Alkhateeb, Fahaid H. Alhashem, Ismaeel bin-Jaliah, Hussein F. Sakr, Hesham M. Elrefaey, Abbas O. Elkarib, Mohammad A. Haidara, Abdullah S. Shatoor, Mohammad A. Khalil

Abstract:

This effect of Resveratrol (RES) against CdCl2- induced toxicity in the rat testes was investigated. Seven experimental groups of adult male rats were formulated as follows: A) Controls + NS, B) Control+ vehicle (saline solution of hydroxypropyl cyclodextrin), C) RES treated, D) CdCl2 +NS, E) CdCl2+ vehicle, F) RES followed by CdCl2 and M) CdCl2 followed by RES. At the end of the protocol, serum levels of FSH, LH, and testosterone were measured in all groups. Testicular levels of TBARS and Super Oxide Dismutase (SOD) activity were also measured. Epidydidimal semen analysis was performed and testicular expression of Bcl-2, p53 and Bax were assessed by RT-PCR. Also, histopathological changes of testes were examined microscopically and described. Pre and Post administration of RES in cadmium chloride-intoxicated rats improved semen parameters including count, motility, daily sperm production and morphology, increased serum concentrations of gonadotropins and testosterone, decreased testicular lipid peroxidation and increased SOD activity. Not only RES attenuated cadmium chloride induced testicular histopathology but was also able to protect against the onset of cadmium chloride testicular toxicity. Cadmium chloride downregulated the anti-apoptotic gene Bcl2 and upregulated the expression of both pro-apoptotic genes p53 and Bax. Resveratrol protected from and partially reversed cadmium chloride testicular via upregulation of Bcl2 and down regulation of p53 and Bax gene expression. Antioxidant activity of RES protects against cadmium chloride testicular toxicity and partially reverses its effect via upregulation of BCl2 and downregulation of p53 and Bax expression. These findings have far reaching implications on subfertility and impotency frequently seen in hypertensive as well as metabolic syndrome patients.

Keywords: resveratrol, cadmium, infertility, sperm, testis, metabolic syndrome

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1673 Music Education in Aged Care: Positive Ageing through Instrumental Music Learning

Authors: Ellina Zipman

Abstract:

This research investigates the place of music education in aged care facilities through the implementation of a program of regular piano lessons for residents. Using a qualitative case study methodology, the research explores aged care residents’ experiences in learning to play the piano. Since the aged care homes are unlikely places for formal learning and since older adults, especially in residential care, are not considered likely candidates for learning, this research opens the door for innovative and transformative thinking about where and to whom educational programs can be delivered. By addressing the educational needs of residents in aged care facilities, this research fills the gap in the literature. The research took place in Australia in two of Melbourne’s residential aged care facilities, engaging two residents (a nonagenarian female and an octogenarian male) to participate in 12-months weekly individual piano lessons. The data was collected through video recording of lessons, observations, interviews, emails, and a reflective journal. Data analysis was done using Nvivo and hard copy analysis with identifications of themes. The case studies revealed that passion for music was a major driver in participants’ motivation to engage in a long-term piano lessons program. This participation led to experiences of positive emotions, positive attitude, successes and challenges, the exercise of control, maintaining and building new relationships, improved self-confidence through autonomy and independent skills development, and discovering new identities through finding a new purpose and new roles in life. Speaking through participants’ voices, this research project demonstrates the importance of music education for older adults and hopes to influence transformation in the residential aged care sector.

Keywords: adult music education, quality of life, passion, positive ageing, wellbeing

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1672 Computational Study on Traumatic Brain Injury Using Magnetic Resonance Imaging-Based 3D Viscoelastic Model

Authors: Tanu Khanuja, Harikrishnan N. Unni

Abstract:

Head is the most vulnerable part of human body and may cause severe life threatening injuries. As the in vivo brain response cannot be recorded during injury, computational investigation of the head model could be really helpful to understand the injury mechanism. Majority of the physical damage to living tissues are caused by relative motion within the tissue due to tensile and shearing structural failures. The present Finite Element study focuses on investigating intracranial pressure and stress/strain distributions resulting from impact loads on various sites of human head. This is performed by the development of the 3D model of a human head with major segments like cerebrum, cerebellum, brain stem, CSF (cerebrospinal fluid), and skull from patient specific MRI (magnetic resonance imaging). The semi-automatic segmentation of head is performed using AMIRA software to extract finer grooves of the brain. To maintain the accuracy high number of mesh elements are required followed by high computational time. Therefore, the mesh optimization has also been performed using tetrahedral elements. In addition, model validation with experimental literature is performed as well. Hard tissues like skull is modeled as elastic whereas soft tissues like brain is modeled with viscoelastic prony series material model. This paper intends to obtain insights into the severity of brain injury by analyzing impacts on frontal, top, back, and temporal sites of the head. Yield stress (based on von Mises stress criterion for tissues) and intracranial pressure distribution due to impact on different sites (frontal, parietal, etc.) are compared and the extent of damage to cerebral tissues is discussed in detail. This paper finds that how the back impact is more injurious to overall head than the other. The present work would be helpful to understand the injury mechanism of traumatic brain injury more effectively.

Keywords: dynamic impact analysis, finite element analysis, intracranial pressure, MRI, traumatic brain injury, von Misses stress

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1671 Fibromyalgia and Personality: A Review of the Different Personality Types Identified

Authors: Lize Tibiriçá, Ronnie Lee, Samantha Behbahani

Abstract:

Fibromyalgia (FM) is a musculoskeletal disorder affecting men and women of different ages and cultures. The cause of this disorder is unknown; however, studies suggest an etiology that involves biological and psychosocial factors. Few studies have shown that a personality type such as neuroticism is associated with chronic pain conditions. Past research has explored whether patients with FM present with a specific personality trait. However, studies have used different methods (i.e. Minnesota Multiphasic Personality Inventory (MMPI), Sociotropy and Autonomy Scale (SAS) and Dysfunctional Attitude Scale (DAS), Tridimensional Personality Questionnaire or Temperament and Character Inventory (TCI), Karolinska scale of personality, Big Five Inventory or NEO Personality Inventory) to explore the connection between FM and a personality type. They have identified personality types that present similar characteristics but vary in the name (i.e. high harm avoidance and low novelty seeking, psychasthenia/muscular tension/somatic anxiety, neuroticism). Although Zuckerman-Kuhlman Personality Questionnaire and the Big Five Inventory differ in terms of content and structure, both of them identify neuroticism as the personality type of FM patients, and the former also identifies these patients as having a low sociability personality trait. Previous research also shows a trend of sociotropic personality style with FM patients that also suffer from Major Depressive Disorder. Participants in these studies were, for the most part, adult female and researchers have recognized that as a limitation and whether their findings can be generalized to men and younger patients with FM. Furthermore, most studies reviewed were conducted in Europe (i.e. Spain) and had a cross-sectional design. Future research should replicate past studies in different countries and consider conducting a longitudinal study. Although it is suspected that FM course is modulated by FM patients’ personality, it is not known whether individuals with similar personalities will develop FM. This review sought to explain the differences and similarities between the personality types identified. Limitations in the studies reviewed were addressed, and considerations for future research and treatment were discussed.

Keywords: chronic pain, fibromyalgia, neuroticism, personality type

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1670 Insulin Resistance in Patients with Chronic Hepatitis C Virus Infection: Upper Egypt Experience

Authors: Ali Kassem

Abstract:

Background: In the last few years, factors such as insulin resistance (IR) and hepatic steatosis have been linked to progression of hepatic fibrosis.Patients with chronic liver disease, and cirrhosis in particular, are known to be prone to IR. However, chronic HCV (hepatitis C) infection may induce IR, regardless of the presence of liver cirrhosis. Our aims are to study insulin resistance (IR) assessed by HOMA-IR (Homeostatic Model Assessment Insulin Resistance) as a possible risk factor in disease progression in cirrhotic patients and to evaluate the role of IR in hepatic fibrosis progression. The correlations of HOMA-IR values to laboratory, virological and histopathological parameters of chronic HCV are also examined. Methods: The study included 50 people divided into 30 adult chronic hepatitis C patients diagnosed by PCR (polymerase chain reaction) within previous 6 months and 20 healthy controls. The functional and morphological status of the liver were evaluated by ultrasonography and laboratory investigations including liver function tests and by liver biopsy. Fasting blood glucose and fasting insulin levels were measured and body mass index and insulin resistance were calculated. Patients having HOMA-IR >2.5 were labeled as insulin resistant. Results: Chronic hepatitis C patients with IR showed significantly higher mean values of BMI (body mass index) and fasting insulin than those without IR (P < 0.000). Patients with IR were more likely to have steatosis (p = 0.006), higher necroinflammatory activity (p = 0.05). No significant differences were found between the two groups regarding hepatic fibrosis. Conclusion: HOMA-IR measurement could represent a novel marker to identify the cirrhotic patients at greater risk for the progression of liver disease. As IR is a potentially modifiable risk factor, these findings may have important prognostic and therapeutic implications. Assessment of IR by HOMA-IR and improving insulin sensitivity are recommended in patients with HCV and related chronic liver disease.

Keywords: hepatic fibrosis, hepatitis C virus infection, hepatic steatosis, insulin resistance

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1669 Investigation of Internal Gettering at Low Temperatures of Metallic Elements in HEM Wafers mc-Si for Photovoltaic Solar Cells

Authors: Abdelghani Boucheham, Djoudi Bouhafs, Nabil Khelifati, Baya Palahouane

Abstract:

The main aim of this study is to investigate the low temperature internal gettering of manganese and chromium transition metals content in p-type multicrystalline silicon grown by Heat Exchanger Method (HEM). The minority carrier lifetime variation, the transition metal elements behavior, the sheet resistivity and the interstitial oxygen concentration after different temperatures annealing under N2 ambient were investigated using quasi-steady state photoconductance technique (QSSPC), secondary ion mass spectroscopy (SIMS), four-probe measurement and Fourier transform infrared spectrometer (FTIR), respectively. The obtained results indicate in the temperature range of 300°C to 700°C that the effective lifetime increases and reaches its maximum values of 28 μs at 500 °C and decreasing to 6 μs at 700 °C. This amelioration is due probably to metallic impurities internal gettering in the extended defects and in the oxygen precipitates as observed on SIMS profiles and the FTIR spectra. From 300 °C to 500 °C the sheet resistivity values rest unchanged at 30 Ohm/sq and rises significantly to reach 45 Ohm/sq for T> 500 °C.

Keywords: mc-Si, low temperature annealing, internal gettering, minority carrier lifetime, interstitial oxygen, resistivity

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1668 Microbial Removal of Polycyclic Aromatic Hydrocarbons from Petroleum Refinery Sludge: A Consortial Approach

Authors: Dheepshika Kodieswaran

Abstract:

The persisting problem in the world that continuously impose our planet at risk is the increasing amounts of recalcitrant. One such issue is the disposal of the Petroleum Refinery Sludge (PRS) which constitutes hydrocarbons that are hazardous to terrestrial and aquatic life. The comparatively safe approach to handling these wastes is by microbial degradation, while the other chemical and physical methods are either expensive and/or produce secondary pollutants. The bacterial and algal systems have different pathways for the degradation of hydrocarbons, and their growth rates vary. This study shows how different bacterial and microalgal strains degrade the polyaromatic hydrocarbon PAHs individually and their symbiotic influence on degradation as well. In this system, the metabolites and gaseous exchange help each other in growth. This method using also aids in the accumulation of lipids in microalgal cells and from which bio-oils can also be extracted. The bacterial strains used in this experiment are reported to be indigenous strains isolated from PRS. The target PAH studied were anthracene and pyrene for a period of 28 days. The PAH degradation kinetics best fitted the Gompertz model, and the order of the kinetics, rate constants, and half-life was determined.

Keywords: petroleum refinery sludge, co-culturing, polycyclic hydrocarbons, microalgal-bacterial consortia

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1667 Fabrication of LiNbO₃ Based Conspicuous Nanomaterials for Renewable Energy Devices

Authors: Riffat Kalsoom, Qurat-Ul-Ain Javed

Abstract:

Optical and dielectric properties of lithium niobates have made them the fascinating materials to be used in optical industry for device formation such as Q and optical switching. Synthesis of lithium niobates was carried out by solvothermal process with and without temperature fluctuation at 200°C for 4 hrs, and behavior of properties for different durations was also examined. Prepared samples of LiNbO₃ were examined in a way as crystallographic phases by using XRD diffractometer, morphology by scanning electron microscope (SEM), absorption by UV-Visible Spectroscopy and dielectric measurement by impedance analyzer. A structural change from trigonal to spherical shape was observed by changing the time of reaction. Crystallite size decreases by the temperature fluctuation and increasing reaction time. Band gap decreases whereas dielectric constant and dielectric loss was increased with increasing time of reaction. Trend of AC conductivity is explained by Joschner’s power law. Due to these significant properties, it finds its applications in devices, such as cells, Q switching and optical switching for laser and gigahertz frequencies, respectively and these applications depend on the industrial demands.

Keywords: lithium niobates, renewable energy devices, controlled structure, temperature fluctuations

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1666 Peg@GDF3:TB3+ – Rb Nanocomposites for Deep-Seated X-Ray Induced Photodynamic Therapy in Oncology

Authors: E.A. Kuchma

Abstract:

Photodynamic therapy (PDT) is considered an alternative and minimally invasive cancer treatment modality compared to chemotherapy and radiation therapy. PDT includes three main components: a photosensitizer (PS), oxygen, and a light source. PS is injected into the patient's body and then selectively accumulates in the tumor. However, the light used in PDT (spectral range 400–700 nm) is limited to superficial lesions, and the light penetration depth does not exceed a few cm. The problem of PDT (poor visible light transmission) can be solved by using X-rays. The penetration depth of X-rays is ten times greater than that of visible light. Therefore, X-ray radiation easily penetrates through the tissues of the body. The aim of this work is to develop universal nanocomposites for X-ray photodynamic therapy of deep and superficial tumors using scintillation nanoparticles of gadolinium fluoride (GdF3), doped with Tb3+, coated with a biocompatible coating (PEG) and photosensitizer RB (Rose Bengal). PEG@GdF3:Tb3+(15%) – RB could be used as an effective X-ray, UV, and photoluminescent mediator to excite a photosensitizer for generating reactive oxygen species (ROS) to kill tumor cells via photodynamic therapy. GdF3 nanoparticles can also be used as contrast agents for computed tomography (CT) and magnetic resonance imaging (MRI).

Keywords: X-ray induced photodynamic therapy, scintillating nanoparticle, radiosensitizer, photosensitizer

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1665 Calycosin Ameliorates Osteoarthritis by Regulating the Imbalance Between Chondrocyte Synthesis and Catabolism

Authors: Hong Su, Qiuju Yan, Wei Du, En Hu, Zhaoyu Yang, Wei Zhang, Yusheng Li, Tao Tang, Wang yang, Shushan Zhao

Abstract:

Osteoarthritis (OA) is a severe chronic inflammatory disease. As the main active component of Astragalus mongholicus Bunge, a classic traditional ethnic herb, calycosin exhibits anti-inflammatory action and its mechanism of exact targets for OA have yet to be determined. In this study, we established an anterior cruciate ligament transection (ACLT) mouse model. Mice were randomized to sham, OA, and calycosin groups. Cartilage synthesis markers type II collagen (Col-2) and SRY-Box Transcription Factor 9 (Sox-9) increased significantly after calycosin gavage. While cartilage matrix degradation index cyclooxygenase-2 (COX-2), phosphor-epidermal growth factor receptor (p-EGFR), and matrix metalloproteinase-9 (MMP9) expression were decreased. With the help of network pharmacology and molecular docking, these results were confirmed in chondrocyte ATDC5 cells. Our results indicated that the calycosin treatment significantly improved cartilage damage, this was probably attributed to reversing the imbalance between chondrocyte synthesis and catabolism.

Keywords: calycosin, osteoarthritis, network pharmacology, molecular docking, inflammatory, cyclooxygenase 2

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1664 Cytotoxic Metabolites from Tagetes minuta L. Growing in Saudi Arabia

Authors: Ali A. A. Alqarni, Gamal A. Mohamed, Hossam M. Abdallah, Sabrin R. M. Ibrahim

Abstract:

Phytochemical investigation of the methanolic extract of aerial parts of Tagetes minuta L. (Family: Asteraceae) using different chromatographic techniques led to the isolation of five compounds; ecliptal (1), scopoletin (2), P-hydroxy benzoic acid (3), patuletin (4), and patuletin-7-O-β-D-glucopyranoside (5) (Figure 1). Their structures were established based on physical, chemical, and spectral data [Ultraviolet (UV), Proton ¹H, Carbon thirteen ¹³C, and Heteronuclear Multiple Bond Correlation (HMBC) NMR], as well as Electrospray Ionization Mass Spectroscopy (ESIMS) and comparison with literature data. Their cytotoxic activity was assessed towards human liver hepatocellular carcinoma (HepG2), human breast cancer (MCF-7), and human colon cancer (HCT116) cancer cell lines using sulphorhodamine B (SRB) assay. It is noteworthy that compound 1 demonstrated a significant cytotoxic potential towards HepG2, MCF7, and HCT116 cells with IC₅₀s ranging from 2.74 to 7.01 μM, compared to doxorubicin (IC₅₀ 0.18, 0.60, and 0.20 μM, respectively), whereas compounds 2, 4, and 5 showed moderate cytotoxic potential with IC50s ranging from 11.71 to 35.64 μM. However, 3 was inactive up to a concentration of 100 μM towards the three tested cancer cell lines.

Keywords: Asteraceae, cytotoxicity, metabolites, Tagetes minuta

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1663 Brazilian Public Security: Governability and Constitutional Change

Authors: Gabriel Dolabella, Henrique Rangel, Stella Araújo, Carlos Bolonha, Igor de Lazari

Abstract:

Public security is a common subject on the Brazilian political agenda. The seventh largest economy in the world has high crime and insecurity rates. Specialists try to explain this social picture based on poverty, inequality or public policies addressed to drug trafficking. This excerpt approaches State measures to handle that picture. Therefore, the public security - law enforcement institutions - is at the core of this paper, particularly the relationship among federal and state law enforcement agencies, mainly ruled by a system of urgency. The problems are informal changes on law enforcement management and public opinion collaboration to these changes. Whenever there were huge international events, Brazilian armed forces occupied streets to assure law enforcement - ensuring the order. This logic, considered in the long time, could impact the federal structure of the country. The post-madisonian theorists verify that urgency is often associated to delegation of powers, which is true for Brazilian law enforcement, but here there is a different delegation: States continuously delegate law enforcement powers to the federal government throughout the use of Armed Forces. Therefore, the hypothesis is: Brazil is under a political process of federalization of public security. The political framework addressed here can be explained by the disrespect of legal constraints and the failure of rule of law theoretical models. The methodology of analysis is based on general criteria. Temporally, this study investigates events from 2003, when discussions about the disarmament statute begun. Geographically, this study is limited to Brazilian borders. Materially, the analysis result from the observation of legal resources and political resources (pronouncements of government officials). The main parameters are based on post-madisonianism and federalization of public security can be assessed through credibility and popularity that allow evaluation of this political process of constitutional change. The objective is to demonstrate how the Military Forces are used in public security, not as a random fact or an isolated political event, in order to understand the political motivations and effects that stem from that use from an institutional perspective.

Keywords: public security, governability, rule of law, federalism

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1662 Effect of Z-VAD-FMK on in Vitro Viability of Dog Follicles

Authors: Leda Maria Costa Pereira, Maria Denise Lopes, Nucharin Songsasen

Abstract:

Mammalian ovaries contain thousands of follicles that eventually degenerate or die after culture in vitro. Caspase-3 is a key enzyme that regulating cell death. Our objective was to examine the influence of anti-apoptotic drug Z-VAD-FMK (pan-caspase inhibitor) on in vitro viability of dog follicles within the ovarian cortex. Ovaries were obtained from prepubertal (age, 2.5–6 months) and adult (age, 8 months to 2 years) bitches and ovarian cortical fragments were recovered. The cortices were then incubated on 1.5% (w/v) agarose gel blocks within a 24-wells culture plate (three cortical pieces/well) containing Minimum Essential Medium Eagle - Alpha Modification (Alpha MEM) supplemented with 4.2 µg/ml insulin, 3.8 µg/ml transferrin, 5 ng/ml selenium, 2 mM L-glutamine, 100 µg/mL of penicillin G sodium, 100 µg/mL of streptomycin sulfate, 0.05 mM ascorbic acid, 10 ng/mL of FSH and 0.1% (w/v) polyvinyl alcohol in humidified atmosphere of 5% CO2 and 5% O2. The cortices were divided in six treatment groups: 1) 10 ng/mL EGF (EGF V0); 2) 10 ng/mL of EGF plus 1 mM Z-VAD-FMK (EGF V1); 3) 10 ng/mL of EGF and 10 mM Z-VAD-FMK (EGF V10); 4) 1 mM Z-VAD-FMK; 5) 10 mM Z-VAD-FMK and (6) no EGF and Z-VAD-FMK supplementation. Ovarian follicles within the tissues were processed for histology and assessed for follicle density, viability (based on morphology) and diameter immediately after collection (Control) or after 3 or 7 days of in vitro incubation. Comparison among fresh and culture treatment group was performed using ANOVA test. There were no differences (P > 0.05) in follicle density and viability among different culture treatments. However, there were differences in this parameter between culture days. Specifically, culturing tissue for 7 days resulted in significant reduction in follicle viability and density, regardless of treatments. We found a difference in size between culture days when these follicles were cultured using 10 mM Z-VAD-FMK or 10 ng/mL EGF (EGF V0). In sum, the finding demonstrated that Z-VAD-FMK at the dosage used in the present study does not provide the protective effect to ovarian tissue during in vitro culture. Future studies should explore different Z-VAD-FMK dosages or other anti-apoptotic agent, such as surviving in protecting ovarian follicles against cell death.

Keywords: anti apoptotic drug, bitches, follicles, Z-VAD-FMK

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1661 The Axonal Connectivity of Motor and Premotor Areas as Revealed through Fiber Dissections: Shedding Light on the Structural Correlates of Complex Motor Behavior

Authors: Spyridon Komaitis, Christos Koutsarnakis, Evangelos Drosos, Aristotelis Kalyvas

Abstract:

This study opts to investigate the intrinsic architecture, morphology, and spatial relationship of the subcortical pathways implicated in the connectivity of the motor/premotor cortex and SMA/pre-SMA complex. Twenty normal, adult, formalin-fixed cerebral hemispheres were explored through the fiber micro-dissection technique. Lateral to medial and medial to lateral dissections focused on the area of interest were performed in a tandem manner and under the surgical microscope. We traced the subcortical architecture, spatial relationships, and axonal connectivity of four major pathways: a) the dorsal component of the SLF (SLF-I) was found to reside in the medial aspect of the hemisphere and seen to connect the precuneus with the SMA and pre-SMA complex, b) the frontal longitudinal system (FLS) was consistently encountered as the natural anterior continuation of the SLF-II and SLF-III and connected the premotor and prefrontal cortices c) the fronto-caudate tract (FCT), a fan-shaped tract, was documented to participate in connectivity of the prefrontal and premotor cortices to the head and body of the caudate nucleus and d) the cortico-tegmental tract(CTT) was invariably recorded to subserve the connectivity of the tegmental area with the fronto-parietal cortex. No hemispheric asymmetries were recorded for any of the implicated pathways. Sub-segmentation systems were also proposed for each of the aforementioned tracts. The structural connectivity and functional specialization of motor and premotor areas in the human brain remain vague to this day as most of the available evidence derives either from animal or tractographic studies. By using the fiber-microdissection technique as our main method of investigation, we provide sound structural evidence on the delicate anatomy of the related white matter pathways.

Keywords: neuroanatomy, premotor, motor, connectivity

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1660 2D Hexagonal Cellular Automata: The Complexity of Forms

Authors: Vural Erdogan

Abstract:

We created two-dimensional hexagonal cellular automata to obtain complexity by using simple rules same as Conway’s game of life. Considering the game of life rules, Wolfram's works about life-like structures and John von Neumann's self-replication, self-maintenance, self-reproduction problems, we developed 2-states and 3-states hexagonal growing algorithms that reach large populations through random initial states. Unlike the game of life, we used six neighbourhoods cellular automata instead of eight or four neighbourhoods. First simulations explained that whether we are able to obtain sort of oscillators, blinkers, and gliders. Inspired by Wolfram's 1D cellular automata complexity and life-like structures, we simulated 2D synchronous, discrete, deterministic cellular automata to reach life-like forms with 2-states cells. The life-like formations and the oscillators have been explained how they contribute to initiating self-maintenance together with self-reproduction and self-replication. After comparing simulation results, we decided to develop the algorithm for another step. Appending a new state to the same algorithm, which we used for reaching life-like structures, led us to experiment new branching and fractal forms. All these studies tried to demonstrate that complex life forms might come from uncomplicated rules.

Keywords: hexagonal cellular automata, self-replication, self-reproduction, self- maintenance

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1659 The Three-Dimensional Kinematics of the Sprint Start in Young Elite Sprinters

Authors: Saeed Ilbeigi, Bart Van Gheluwe

Abstract:

The purpose of this study was to identify the three-dimensional kinematics of the sprint start during the start phase of the sprint. The purpose of this study was to identify the three-dimensional kinematics of the sprint start during the start phase of the sprint. Moreover, the effect of anthropometrical factors such as skeletal muscle mass, thigh girth, and calf girth also were considered on the kinematics of the sprint start. Among all young sprinters involved in the national Belgium league, sixty sprinters (boys: 14.7 ± 1.8 years and girls: 14.8±1.5 years) were randomly selected. The kinematics data of the sprint start were collected with a Vicon® 620 motion analysis system equipped with 12 infrared cameras running at 250 Hz and running the Vicon Data Station software. For statistical analysis, T-tests and ANOVA׳s with Scheffé post hoc test were used and the significant level was set as p≤0.05. The results showed that the angular positions of the lower joints of the young sprinters in the set position were comparable with adult figures from literature, however, with a greater range of joint extension. The most significant difference between boys and girls was found in the set position, where the boys presented a more dorsiflexed ankle. No further gender effect was observed during the leaving the blocks and contact phase. The sprinters with a higher age, skeletal muscle mass, thigh girth, and calf girth displayed a better angular position of the lower joints (e.g. ankle, knee, hip) in the set position, a more optimal angular position for the foot and knee for absorbing impact forces at foot contact and finally a higher range of flexion/extension motion to produce force and power when leaving the blocks.

Keywords: anthropometry, kinematics, sprint start, young elite sprinters

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1658 Hesperidin through Acting on Proliferating Cell Nuclear Antigen and Follicle Stimulating Hormone Receptor Expression Decreased Ovarian Toxicity Induced by Malathion

Authors: Mahnaz Zarein, Hamed Shoorei

Abstract:

Background: Malathion is one of the most toxic agents widely used in agriculture throughout the world. This agent has adverse effects on the functions of multiple organs such as the reproductive system in both male and female genders. On the one hand, daily use of antioxidant supplementations such as hesperidin is capable to neutralize the deleterious impacts of malathion. Therefore, in this experimental study, the protective effects of hesperidin against ovarian toxicity induced by malathion were investigated. Material & Methods: Balb/c adult mice (n=32) were randomly divided into 4 groups including 1) the control group, treated with normal saline, 2) the Mal group, treated with 30mg/kg malathion, daily for 1 month, 3) Mal + Hes group, treated with 20 mg/kg malathion and 20 mg/kg hesperidin, daily for 1 month, and 5) Hes group, treated with 20 mg/kg hesperidin. At the end of the experimental period, mice were anesthetized and their drops of blood were collected to the assessment of some hormones such as LH, FSH, E2, and P4. Also, the right ovaries were used to H&E staining, and the left ovaries were used for IHC staining (PCNA and FSHR). Results: Histopathological assessments showed that the number of follicles, i.e. primordial, primary, and secondary, significantly decreased, while the atretic follicle counts remarkably increased compared to the control group (p<0.05). Hormonal levels revealed that the production of all mentioned hormones decreased in the Mal group in comparison with the control group (p<0.05). The expression of PCNA, as a proliferative marker, and FHSR, as a marker showing maturation, decreased when mice received malathion compared to the control group (p<0.05). Interestingly, treatment with hesperidin significantly neutralized the adverse effects of malathion on all mentioned parameters. Conclusion: Daily use of antioxidant supplementations such as hesperidin could alleviate the ovarian toxicity induced by malathion.

Keywords: malathion, ovary, antioxidant hesperidin, FSHR PCNA, ovary

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1657 The Effect of Second Language Listening Proficiency on Cognitive Control among Young Adult Bilinguals

Authors: Zhilong Xie, Jinwen Huang, Guofang Zeng

Abstract:

The existing body of research on bilingualism has consistently linked the use of multiple languages to enhanced cognitive control. Numerous studies have demonstrated that bilingual individuals exhibit advantages in non-linguistic tasks demanding cognitive control. However, recent investigations have challenged these findings, leading to a debate regarding the extent and nature of bilingual advantages. The adaptive control hypothesis posits that variations in bilingual experiences hold the key to resolving these controversies. This study aims to contribute to this discussion by exploring the impact of second language (L2) listening experience on cognitive control among young Chinese-English bilinguals. By examining this specific aspect of bilingualism, the study offers a perspective on the origins of bilingual advantages. This study employed a range of cognitive tasks, including the Flanker task, Wisconsin Card Sorting Test (WCST), Operation Span Task (OSPAN), and a second language listening comprehension test. After controlling for potential confounding variables such as intelligence, socioeconomic status, and overall language proficiency, independent sample t-test analysis revealed significant differences in performance between groups with high and low L2 listening proficiency in the Flanker task and OSPAN. However, no significant differences emerged between the two groups in the WCST. These findings suggest that L2 listening proficiency has a significant impact on inhibitory control and working memory but not on conflict monitoring or mental set shifting. These specific findings provide a more nuanced understanding of the origins of bilingual advantages within a specific bilingual context, highlighting the importance of considering the nature of bilingual experience when exploring cognitive benefits.

Keywords: bilingual advantage, inhibitory control, L2 listening, working memory

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1656 Laboratory Calibration of Soil Pressure Transducer for a Specified Field Application

Authors: Mohammad Zahidul Islam Bhuiyan, Shanyong Wang, Scott William Sloan, Daichao Sheng

Abstract:

Nowadays soil pressure transducers are widely used to measure the soil stress states in laboratory and field experiments. The soil pressure transducers, investigated here, are traditional diaphragm-type earth pressure cells (DEPC) based on strain gauge principle. It is found that the output of these sensors varies with the soil conditions as well as the position of a sensor. Therefore, it is highly recommended to calibrate the pressure sensors based on the similar conditions of their intended applications. The factory calibration coefficients of the EPCs are not reliable to use since they are normally calibrated by applying fluid (a special type of oil) pressure only over load sensing zone, which does not represent the actual field conditions. Thus, the calibration of these sensors is utmost important, and they play a pivotal role for assessing earth pressures precisely. In the present study, TML soil pressure sensor is used to compare its sensitivity under different calibration systems, for example, fluid calibration, and static load calibration with or without soil. The results report that the sensor provides higher sensitivity (more accurate results) under soil calibration system.

Keywords: calibration, soil pressure, earth pressure cell, sensitivity

Procedia PDF Downloads 240