Search results for: cone contrast sensitivity

Authors: Salah Hadjout, Mohamed Zouidi

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In Algeria, several works carried out in recent years have shown the importance of fusarium head blight in durum wheat. Indeed, this disease is caused by a complex of Fusarium genus pathogens. The research carried out reports that F. culmorum is the main species infecting cereals. These informations motivated our interest in the field evaluation of the behavior of some durum wheat genotypes (parental varieties and lines) with regard to fusarium head blight, mainly caused by four F. culmorum isolates. Our research work focused on following the evolution of symptom development throughout the grain filling, after artificial inoculation of ears by Fusarium isolates in order to establish a first image on the differences in genotype behavior to fusarium haed blight. Field disease assessment criteria are: disease assessment using a grading scale, thousand grain weight measurement and AUDPC. The results obtained revealed that the varieties and lines resulting from crosses had a quite different level of sensitivity to F. culmorum species and no genotype showed complete resistance in our culture conditions. Among the material tested, some lines showed higher resistance than their parents. The results also show a slight behavioral variability also linked to the aggressiveness of the Fusarium species studied in this work. Our results open very important research perspectives on fusarium head blight, in particular the search for toxins produced by Fusarium species.

Keywords: fusarium head blight, durum wheat, Fusarium culmorum, field disease assessment criteria, Algeria

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Authors: W. Fatmi, F. Kriba, Z. Kechrid

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The aim of this study was to investigate the effect of vitamin C on blood biochemical parameters, tissue zinc, and antioxidants enzymes in diabetic rats fed a zinc-deficient diet. For that purpose, Alloxan-induced diabetic rats were divided into four groups. The first group was fed a zinc-sufficient diet while the second group was fed a zinc-deficient diet. The third and fourth groups received zinc-sufficient or zinc-deficient diets plus oral vitamin C (1mg/l) for 27 days. Body weight and food intake were recorded regularly during 27 days. On day 28, animals were killed and glucose, total lipids, triglycerides, protein, urea, serum zinc , tissues zinc concentrations, liver glycogen, GSH, TBARS concentrations and serum GOT, GPT, ALP and LDH, liver GSH-Px, GST and Catalase activities were determined. Body weight gain and food intake of zinc deficient diabetic animals at the end of experimental period was significantly lower than that of zinc adequate diabetic animals. Dietary zinc intake significantly increased glucose, lipids, triglycerides, urea, and liver TBARS levels of zinc deficient diabetic rats. In contrast, serum zinc, tissues zinc, protein, liver glycogen and GSH levels were decreased. The consumption of zinc deficient diet led also to an increase in serum GOT, GPT and liver GST accompanied with a decrease in serum ALP, LDH and liver GSH-Px, CAT activities. Meanwhile, vitamin C treatment was ameliorated all the previous parameters approximately to their normal levels. Vitamin C supplementation presumably acting as an antioxidant, and it probably led to an improvement of insulin activity, which significantly reduced the severity of zinc deficiency in diabetes.

Keywords: antioxidant, experimental diabetes, liver enzymes, vitamin c, zinc deficiency

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Authors: Samaneh Nazemi, Ayla Bahramian, Marzieh Aghazadeh

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Saliva is a clear liquid composed of water, electrolytes, glucose, amylase, glycoproteins, and antimicrobial enzymes. The presence of a wide range of molecules and proteins in saliva has made this fluid valuable in screening for some diseases as well as epidemiological studies. Saliva is easier than serum to collect in large populations. Due to the importance of sodium and glucose levels in many biological processes, this study investigates the relationship between sodium and glucose levels in salivary and serum samples of healthy individuals referring to Tabriz Dental School. This descriptive-analytical study was performed on 40 healthy individuals referred to the Oral Diseases Department of Tabriz Dental School. Serum and saliva samples were taken from these patients according to standard protocols. Data were presented as mean (standard deviation) and frequency (percentage) for quantitative and qualitative variables. Pearson test, paired-samples T-test and SPSS 24 software were used to determine the correlation between serum and salivary levels of these biomarkers. In this study, P less than 0.05% is considered significant. Out of 40 participants in this study, 14 (35%) were male, and 26 (65%) were female. According to the results of this study, the mean salivary sodium (127.53 ml/dl) was lower than the mean serum sodium (141.2725 ml/dl). In contrast, the mean salivary glucose (4.55 ml/dl) was lower than the mean serum glucose (89.7575 ml/dl). The result of paired samples T-test (p-value<0.05) showed that there is a statistically significant difference between the mean of serum sodium and salivary sodium, as well as between the serum glucose and salivary glucose. Pearson correlation test results showed that there is no significant correlation between serum sodium and salivary sodium (p-value >0.05), but here is a positive correlation between serum glucose and salivary glucose (p-value<0.001). Both serum sodium and glucose were higher than salivary sodium and glucose.In conclusion, this study found that there was not a statistical relationship between salivary glucose and serum glucose and also salivary sodium and serum sodium of healthy individuals. Perhaps salivary samples can’t be used to measure glucose and sodium in these individuals.

Keywords: glucose, saliva, serum, sodium

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Authors: Bibire Abdulkareem Hussein

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Job satisfaction and motivation are considered as major tools in sustaining institutional development, they are also the machinery used to achieve an institutional goals and objectives. However, it has been observed that some institutions failed in motivating and stimulating their workers; in contrast, workers may be motivated but not satisfied with the job and failed to perform efficiently and effectively. It is hoped that the study of this nature would be of significance value to all stakeholders in education specifically, lecturers in higher institutions in Nigeria. Also it significances will enhance lecturers’ effectiveness and performance in discharging their duties. It is against this backdrop that, this study investigated whether job satisfaction and motivation predict lecturers’ effectiveness in Nigeria Police Academy, Wudil, KanoState. The correlational research method was adopted for the study while purposive sampling technique was used to choose the institution and the sampled lectures (70). Simple random sampling technique was used to select one hundred cadets across the academy. Two instruments were used to elicit information from both lecturers and cadets. These were job satisfaction and motivation; and lecturers’ effectiveness Questionnaires. The instruments were subjected to pilot testing and found to have reliability coefficient of 0.69 and 0.71 respectively. The results of the study revealed that there was a significance relationship among job satisfaction, motivation and lecturers effectiveness in Nigeria Police Academy, Job satisfaction had a Beta weight (β) of .125, t = 3.253, p<0.05, Job motivation had a Beta weight (β) of .185, t = 3.849, p<0.05. There was a significance relationship between job satisfaction and lecturers’ effectiveness in Nigeria Police Academy the cal r is 0.21 while the crt r is 0.19. at p<0.05 and; there was a significance relationship between job motivation and lecturers effectiveness in Nigeria Police Academy the cal r is 0.20 while the crt r is 0.19 at p<0.05This study therefore concluded that there was a significance relationship among job satisfaction, motivation and lecturers effectiveness in Nigeria Police Academy s,In view of the findings of this study, the paper recommends that lecturers should be more pro-active and more effective in their primary assignment (teaching) in order to make meaningful impacts and inputs in the life of cadets and boost the standard of the academy. In the same vein, it is recommended that management should intensify efforts to improve lecturers’ welfares by providing more motivational techniques to enhance more productivity.

Keywords: academy, lecturers effectiveness, motivation, satisfaction

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Authors: Bita Payami-Shabestari, Dariush Eslami

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The purpose of this paper is to develop a multi-product economic production quantity model under vendor management inventory policy and restrictions including limited warehouse space, budget, and number of orders, average shortage time and maximum permissible shortage. Since the “costs” cannot be predicted with certainty, it is assumed that data behave under uncertain environment. The problem is first formulated into the framework of a bi-objective of multi-product economic production quantity model. Then, the problem is solved with three multi-objective decision-making (MODM) methods. Then following this, three methods had been compared on information on the optimal value of the two objective functions and the central processing unit (CPU) time with the statistical analysis method and the multi-attribute decision-making (MADM). The results are compared with statistical analysis method and the MADM. The results of the study demonstrate that augmented-constraint in terms of optimal value of the two objective functions and the CPU time perform better than global criteria, and goal programming. Sensitivity analysis is done to illustrate the effect of parameter variations on the optimal solution. The contribution of this research is the use of random costs data in developing a multi-product economic production quantity model under vendor management inventory policy with several constraints.

Keywords: economic production quantity, random cost, supply chain management, vendor-managed inventory

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Authors: Zair Nadje, Attoui Badra, Miloudi Abdelmonem

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This study aims to assess sensitivity to nitrate pollution and monitor the temporal evolution of nitrate contents in groundwater using statistical models and map their spatial distribution. The nitrate levels observed in the waters of the town of El-Oued differ from one aquifer to another. Indeed, the waters of the Quaternary aquifer are the richest in nitrates, with average annual contents varying from 6 mg/l to 85 mg/l, for an average of 37 mg/l. These levels are higher than the WHO standard (50 mg/l) for drinking water. At the water level of the Terminal Complex (CT) aquifer, the annual average nitrate levels vary from 14 mg/l to 37 mg/l, with an average of 18 mg/l. In the Terminal Complex, excessive nitrate levels are observed in the central localities of the study area. The spatial distribution of nitrates in the waters of the Quaternary aquifer shows that the majority of the catchment points of this aquifer are subject to nitrate pollution. This study shows that in the waters of the Terminal Complex aquifer, nitrate pollution evolves in two major areas. The first focus is South-North, following the direction of underground flow. The second is West-East, progressing towards the East zone. The temporal distribution of nitrate contents in the water of the Terminal Complex aquifer in the city of El-Oued showed that for decades, nitrate contents have suffered a decline after an increase. This evolution of nitrate levels is linked to demographic growth and the rapid urbanization of the city of El-Oued.

Keywords: anthropogenic activities, groundwater, nitrates, pollution, arid zones city of El-Oued, Algeria

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Authors: Kwak, Hyo-Gyung, Gang, Han Gul

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In the context of an increasing need for reliability and safety in concrete structures under blast and impact loading condition, the behavior of concrete under high strain rate condition has been an important issue. Since concrete subjected to impact loading associated with high strain rate shows quite different material behavior from that in the static state, several material models are proposed and used to describe the high strain rate behavior under blast and impact loading. In the process of modelling, in advance, mesh dependency in the used finite element (FE) is the key problem because simulation results under high strain-rate condition are quite sensitive to applied FE mesh size. It means that the accuracy of simulation results may deeply be dependent on FE mesh size in simulations. This paper introduces an improved criterion which can minimize the mesh-dependency of simulation results on the basis of the fracture energy concept, and HJC (Holmquist Johnson Cook), CSC (Continuous Surface Cap) and K&C (Karagozian & Case) models are examined to trace their relative sensitivity to the used FE mesh size. To coincide with the purpose of the penetration test with a concrete plate under a projectile (bullet), the residual velocities of projectile after penetration are compared. The correlation studies between analytical results and the parametric studies associated with them show that the variation of residual velocity with the used FE mesh size is quite reduced by applying a unique failure strain value determined according to the proposed criterion.

Keywords: high strain rate concrete, penetration simulation, failure strain, mesh-dependency, fracture energy

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Authors: S. M. Abdul Khader, Anurag Ayachit, Raghuvir Pai, K. A. Ahmed, V. R. K Rao, S. Ganesh Kamath

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The numerical simulation has made tremendous advances in investigating the blood flow phenomenon through elastic arteries. Such study can be useful in demonstrating the disease progression and haemodynamics of cardiovascular diseases such as atherosclerosis. In the present study, patient specific case diagnosed with partially stenosed complete right ICA and normal left carotid bifurcation without any atherosclerotic plaque formation is considered. 3D patient specific carotid bifurcation model is generated based on CT scan data using MIMICS-4.0 and numerical analysis is performed using FSI solver in ANSYS-14.5. The blood flow is assumed to be incompressible, homogenous and Newtonian, while the artery wall is assumed to be linearly elastic. The two-way sequentially-coupled transient FSI analysis is performed using FSI solver for three pulse cycles. The haemodynamic parameters such as flow pattern, Wall Shear Stress, pressure contours and arterial wall deformation are studied at the bifurcation and critical zones such as stenosis. The variation in flow behavior is studied throughout the pulse cycle. Also, the simulation results reveals that there is a considerable increase in the flow behavior in stenosed carotid in contrast to the normal carotid bifurcation system. The investigation also demonstrates the disturbed flow pattern especially at the bifurcation and stenosed zone elevating the haemodynamics, particularly during peak systole and later part of the pulse cycle. The results obtained agree well with the clinical observation and demonstrates the potential of patient specific numerical studies in prognosis of disease progression and plaque rupture.

Keywords: fluid-structure interaction, arterial stenosis, wall shear stress, carotid artery bifurcation

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Authors: Riya Thomas, Denis Music, Tautgirdas Ruzgas

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The detection of tyrosinase holds considerable interest in the domains of food nutrition and human health due to its significant role in causing a detrimental effect on the colour, flavour, and nutritional value of food as well as in the synthesis of melanin causing skin melanoma. Compared to other conventional analytical techniques, electrochemical (EC) sensors are highly promising owing to their quick response, great sensitivity, ease of use, and low cost. Particularly, titania nanoparticle-based electrochemical sensors have drawn special attention in identifying several biomolecules including enzymes, antibodies, and receptors, owing to their enhanced electrocatalytic activity and electron-accepting properties. In this study, Ti-O film-modified electrode is fabricated using reactive magnetron sputtering, and its affinity towards tyrosinase is examined via electrochemical methods. To comprehend the physiochemical and surface properties-governed electrocatalytic activity of modified electrodes, Ti-O films are grown under various compositional ranges and deposition temperature, and their corresponding electrochemical activity towards tyrosinase is studied. Further, to understand the underlying atomistic mechanisms and electronic-scale electrochemical characteristics, density functional theory (DFT) is employed. The main goal of the current work is to determine the correlation between macroscopic measurements and the underlying atomic properties to improve the tyrosinase activity on Ti-O surfaces. Moreover, this work offers an intriguing new perspective on the use of Ti-O-modified electrodes to detect tyrosinase in the areas of clinical diagnosis, skincare, and food science.

Keywords: density functional theory, electrochemical sensor, Ti-O film, tyrosinase

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Authors: Emery A. Coppola Jr., Suna Cinar, Ferenc Szidarovszky

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Over-pumping of groundwater resources is a serious problem world-wide. In addition to depleting this valuable resource, hydraulically connected sensitive ecological resources like wetlands and surface water bodies are often impacted and even destroyed by over-pumping. Effectively managing groundwater in a way that satisfy human demand while preserving natural resources is a daunting challenge that will only worsen with growing human populations and climate change. As presented in this paper, a numerical flow model developed for a hypothetical but realistic groundwater/surface water system was combined with formal optimization. Response coefficients were used in an optimization management model to maximize groundwater pumping in a complex, multi-layered aquifer system while protecting against groundwater over-draft, streamflow depletion, and wetland impacts. Pumping optimization was performed for different constraint sets that reflect different resource protection preferences, yielding significantly different optimal pumping solutions. A sensitivity analysis on the optimal solutions was performed on select response coefficients to identify differences between wet and dry periods. Stochastic optimization was also performed, where uncertainty associated with changing irrigation demand due to changing weather conditions are accounted for. One of the strengths of this optimization approach is that it can efficiently and accurately identify superior management strategies that minimize risk and adverse environmental impacts associated with groundwater pumping under different hydrologic conditions.

Keywords: numerical groundwater flow modeling, water management optimization, groundwater overdraft, streamflow depletion

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Authors: Ahmet Erten, Adil Mustafa, Ayşenur Eser, Özlem Yalçın

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We present a new viscometer based on a microfluidic chip with elastic high aspect ratio micropillar arrays. The displacement of pillar tips in flow direction can be used to analyze viscosity of liquid. In our work, Computational Fluid Dynamics (CFD) is used to analyze pillar displacement of various micropillar array configurations in flow direction at different viscosities. Following CFD optimization, micro-CNC based rapid prototyping is used to fabricate molds for microfluidic chips. Microfluidic chips are fabricated out of polydimethylsiloxane (PDMS) using soft lithography methods with molds machined out of aluminum. Tip displacements of micropillar array (300 µm in diameter and 1400 µm in height) in flow direction are recorded using a microscope mounted camera, and the displacements are analyzed using image processing with an algorithm written in MATLAB. Experiments are performed with water-glycerol solutions mixed at 4 different ratios to attain 1 cP, 5 cP, 10 cP and 15 cP viscosities at room temperature. The prepared solutions are injected into the microfluidic chips using a syringe pump at flow rates from 10-100 mL / hr and the displacement versus flow rate is plotted for different viscosities. A displacement of around 1.5 µm was observed for 15 cP solution at 60 mL / hr while only a 1 µm displacement was observed for 10 cP solution. The presented viscometer design optimization is still in progress for better sensitivity and accuracy. Our microfluidic viscometer platform has potential for tailor made microfluidic chips to enable real time observation and control of viscosity changes in biological or chemical reactions.

Keywords: Computational Fluid Dynamics (CFD), high aspect ratio, micropillar array, viscometer

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Authors: Amir Ali, Laura Yael Mendoza

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The application of nanomaterials is becoming the most effective strategy of elicitation to produce a desirable level of plant biomass with complex medicinal compounds. This study was designed to check the influence of phytosynthesized iron nanoparticles (FeNPs) on physical growth characteristics, antioxidant status, and production of steviol glycosides of in vitro grown Stevia rebaudiana. Effect of different concentrations of iron nanoparticles replacement of iron sulfate in MS medium (stock solution) on invitro stevia plant growth following positive control (MS basal medium), negative control (iron sulfate devoid medium), iron sulfate devoid MS medium and supplemented with FeNPs at different concentrations (5.6 mg/L, 11.2 mg/L, 16.8 mg/L, 22.4 mg/L) was evaluated. The iron deficiency leads to a drastic reduction in plant growth. In contrast, applying FeNPs leads to improvement in plant height, leave diameter, improved leave morphology, etc., in a concentration-dependent manner. Furthermore, the stress caused by FeNPs at 16.8 mg/L in cultures produced higher levels of total phenolic content (3.7 ± 0.042 mg/g dry weight: DW) and total flavonoid content (1.9 ± 0.022 mg/g DW and antioxidant activity (78 ± 4.6%). In addition, plants grown in the presence of FeNPs at 22.4 mg/L resulted in higher enzymatic antioxidant activities (SOD = 3.5 ± 0.042 U/mg; POD = 2.6 ± 0.026 U/mg; CAT = 2.8 ± 0.034 U/mg and APx = 3.6 ± 0.043 U/ mg), respectively. Furthermore, exposure to a higher dose of FeNPs (22.4 mg/L) exhibited the maximum amount of stevioside (stevioside: 4.6 ± 0.058 mg/g (DW) and rebaudioside A: 4.9 ± 0.068 mg/g DW) as compared to other doses. The current investigation confirms the effectiveness of FeNPs in growth media. It offers a suitable prospect for commercially desirable production of S. rebaudiana biomass with higher sweet glycosides profiles in vitro.

Keywords: cell culture, stevia, iron nanoparticles, antioxidants

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Authors: Khadijat Olabisi Abdulwahab, Mohammad Azad Malik, Paul O'Brien, Grigore Timco, Floriana Tuna

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The synthesis of spinel ferrite nanoparticles with a narrow size distribution is very crucial in their numerous applications including information storage, hyperthermia treatment, drug delivery, contrast agent in magnetic resonance imaging, catalysis, sensors, and environmental remediation. Ferrites have the general formula MFe₂O₄ (M = Fe, Co, Mn, Ni, Zn e.t.c) and possess remarkable electrical and magnetic properties which depend on the cations, method of preparation, size and their site occupancies. To the best of our knowledge, there are no reports on the use of a single source precursor to synthesise quaternary ferrite nanoparticles. Here in, we demonstrated the use of trimetallic iron pivalate cluster [CrCoFeO(O₂CᵗBu)₆(HO₂CᵗBu)₃] as a single source precursor to synthesise monodisperse cobalt chromium ferrite (FeCoCrO₄) nanoparticles by the hot injection thermolysis method. The precursor was thermolysed in oleylamine, oleic acid, with diphenyl ether as solvent at 260 °C. The effect of reaction time on the stoichiometry, phases or morphology of the nanoparticles was studied. The p-XRD patterns of the nanoparticles obtained after one hour was pure phase of cubic iron cobalt chromium ferrite (FeCoCrO₄). TEM showed that a more monodispersed spherical ferrite nanoparticles were obtained after one hour. Magnetic measurements revealed that the ferrite particles are superparamagnetic at room temperature. The nanoparticles were characterised by Powder X-ray Diffraction (p-XRD), Transmission Electron Microscopy (TEM), Energy Dispersive Spectroscopy (EDS) and Super Conducting Quantum Interference Device (SQUID).

Keywords: cobalt chromium ferrite, colloidal, hot injection thermolysis, monodisperse, reaction time, single source precursor, quaternary ferrite nanoparticles

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Authors: Xiuxia Sun, Yan Jin, Zilong Liu, Shiming Wei

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As a critical mineral component of shale, illite is essential in oil exploration and development due to its surface hydration characteristics and action mechanism. This paper, starting from the perspective of the molecular structure of organic matter, uses molecular dynamics simulation technology to deeply explore the interaction mechanism between organic molecules and the illite surface. In the study, we thoroughly considered the forces such as van der Waals force, electrostatic force, and steric hindrance and constructed an illite crystal model covering C8-C18 modifiers. Subsequently, we systematically analyzed surfactants' adsorption behavior and hydration characteristics with different alkyl chain numbers, lengths, and concentrations on the illite surface. The simulation results show that surfactant molecules with shorter alkyl chains present a lateral monolayer or inclined double-layer arrangement on the illite surface, and these two arrangements may coexist under different concentration conditions. In addition, with the increase in the number of alkyl chains, the interlayer spacing of illite increases significantly. In contrast, the change in alkyl chain length has a limited effect on surface properties. It is worth noting that the change in functional group structure has a particularly significant effect on the wettability of the illite surface, and its influence even exceeds the change in the alkyl chain structure. This discovery gives us a new perspective on understanding and regulating the wetting properties. The results obtained are consistent with the XRD analysis and wettability experimental data in this paper, further confirming the reliability of the research conclusions. This study deepened our understanding of illite's hydration characteristics and mechanism. We provided new ideas and directions for the molecular design and application development of oilfield chemicals.

Keywords: illite, surfactant, hydration, wettability, adsorption

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Authors: Marina Kapsali, John S. Anagnostopoulos

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Greek islands’ interconnection (IC) with larger power systems, such as the mainland grid, is a crucial issue that has attracted a lot of interest; however, the recent economic recession that the country undergoes together with the highly capital intensive nature of this kind of projects have stalled or sifted the development of many of those on a more long-term basis. On the other hand, most of Greek islands are still heavily dependent on the lengthy and costly supply chain of oil imports whilst the majority of them exhibit excellent potential for wind energy (WE) applications. In this respect, the main purpose of the present work is to investigate −through a parametric study which varies both in wind farm (WF) and submarine IC capacities− the impact of large-scale WE development on the IC of the third in size island of Greece (Lesbos) with the mainland system. The energy and economic performance of the system is simulated over a 25-year evaluation period assuming two possible scenarios, i.e. S(a): without the contribution of the local Thermal Power Plant (TPP) and S(b): the TPP is maintained to ensure electrification of the island. The economic feasibility of the two options is investigated in terms of determining their Levelized Cost of Energy (LCOE) including also a sensitivity analysis on the worst/reference/best Cases. According to the results, Lesbos island IC presents considerable economic interest for covering part of island’s future electrification needs with WE having a vital role in this challenging venture.

Keywords: electricity generation cost, levelized cost of energy, mainland grid, wind energy rejection

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Authors: Abdullah Alaklabi, Ibrahim A. Arif, Sameera O. Bafeel, Ahmad H. Alfarhan, Anis Ahamed, Jacob Thomas, Mohammad A. Bakir

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Diospyros mespiliformis (Hochst. ex A.DC.; Ebenaceae) is a large deciduous medicinal plant. This plant species is currently listed as endangered in Saudi Arabia. Molecular identification of this plant species based on short sequence regions (571 and 664 bp) of plastid rbcL (ribulose-1, 5-biphosphate carboxylase) gene was investigated in this study. The endangered plant specimens were collected from Al-Baha, Saudi Arabia (GPS coordinate: 19.8543987, 41.3059349). Phylogenetic tree inferred from the rbcL gene sequences showed that this species is very closely related with D. brandisiana. The close relationship was also observed among D. bejaudii, D. Philippinensis and D. releyi (≥99.7% sequence homology). The partial rbcL gene sequence region (571 bp) that was amplified by rbcL primer-pair rbcLaF-rbcLaR failed to discriminate D. mespiliformis from the closely related plant species, D. brandisiana. In contrast, primer-pair rbcL1F-rbcL724R yielded longer amplicon, discriminated the species from D. brandisiana and demonstrated nucleotide variations in 3 different sites (645G>T; 663A>C; 710C>G). Although D. mespiliformis (EU980712) and D. brandisiana (EU980656) are very closely related species (99.4%); however, studied specimen showed 100% sequence homology with D. mespiliformis and 99.6% with D. brandisiana. The present findings showed that rbcL short sequence region (664 bp) of plastid rbcL gene, amplified by primer-pair rbcL1F-rbcL724R, can be used for authenticating samples of D. mespiliforformis and may provide help in authentic identification and management process of this medicinally valuable endangered plant species.

Keywords: Diospyros mespiliformis, endangered plant, identification partial rbcL

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Authors: Asma Alhuqail, Nagwa Aref

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Programmed cell death resembles a real nature active defense in Datura metel against TMV after three days of virus infection. Physiological plant response was assessed for asymptomatic healthy and symptomatic infected detached leaves. The results indicated H2O2 and Chlorophyll-a as the most potential parameters. Chlorophyll-a was considered the only significant predictor variant for the H2O2 dependent variant with a P value of 0.001 and R-square of 0.900. The plant immune response was measured within three days of virus infection using the cutoff value of H2O2 (61.095 lmol/100 mg) and (63.201 units) for the tail moment in the Comet Assay. Their percentage changes were 255.12% and 522.40% respectively which reflects the stress of virus infection in the plant. Moreover, H2O2 showed 100% specificity and sensitivity in the symptomatic infected group using the receiver-operating characteristic (ROC). All tested parameters in the symptomatic infected group had significant correlations with twenty-five positive and thirty-one negative correlations where the P value was <0.05 and 0.01. Chlorophyll-a parameter had a crucial role of highly significant correlation between total protein and salicylic acid. Contrarily, this correlation with tail moment unit was (r = _0.930, P <0.01) where the P value was < 0.01. The strongest significant negative correlation was between Chlorophyll-a and H2O2 at P < 0.01, while moderate negative significant correlation was seen for Chlorophyll-b where the P value < 0.05. The present study discloses the secret of the three days of rapid transient production of activated oxygen species (AOS) that was enough for having potential quantitative physiological parameters for defensive plant response toward the virus.

Keywords: programmed cell death, plant–adaptive immune response, hydrogen peroxide (H2O2), physiological parameters

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Authors: Huajuan Shi

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Background: The biopsy of the preimplantation embryo may increase the potential risk and concern of embryo viability. Clinically discarded spent embryo medium (SEM) has entered the view of researchers, sparking an interest in noninvasive embryo screening. However, one of the major restrictions is the extremelty low quantity of cf-RNA, which is difficult to efficiently and unbiased amplify cf-RNA using traditional methods. Hence, there is urgently need to an efficient and low bias amplification method which can comprehensively and accurately obtain cf-RNA information to truly reveal the state of SEM cf-RNA. Result: In this present study, we established an agarose PCR amplification system, and has significantly improved the amplification sensitivity and efficiency by ~90 fold and 9.29 %, respectively. We applied agarose to sequencing library preparation (named AG-seq) to quantify and characterize cf-RNA in SEM. The number of detected cf-RNAs (3533 vs 598) and coverage of 3' end were significantly increased, and the noise of low abundance gene detection was reduced. The increasing percentage 5' end adenine and alternative splicing (AS) events of short fragments (< 400 bp) were discovered by AG-seq. Further, the profiles and characterizations of cf-RNA in spent cleavage medium (SCM) and spent blastocyst medium (SBM) indicated that 4‐mer end motifs of cf-RNA fragments could remarkably differentiate different embryo development stages. Significance: This study established an efficient and low-cost SEM amplification and library preparation method. Not only that, we successfully described the characterizations of SEM cf-RNA of preimplantation embryo by using AG-seq, including abundance features fragment lengths. AG-seq facilitates the study of cf-RNA as a noninvasive embryo screening biomarker and opens up potential clinical utilities of trace samples.

Keywords: cell-free RNA, agarose, spent embryo medium, RNA sequencing, non-invasive detection

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Authors: Ghibeche Abderrahmane

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To examine whether genes associated with cellular defense against oxidative stress are associated with insulin sensitivity, patients with type 2 diabetes (n=7) and age-matched (n=5) and young (n=9) control subjects underwent a euglycemic-hyperinsulinemic clamp for 120 min. Muscle samples were obtained before and after the clamp and analyzed for heat shock protein (HSP)72 and heme oxygenase (HO)-1 mRNA, intramuscular triglyceride content, and the maximal activities of β-hyroxyacyl-CoA dehydrogenase (β-HAD) and citrate synthase (CS). Basal expression of both HSP72 and HO-1 mRNA were lower (P < 0.05) by 33 and 55%, respectively, when comparing diabetic patients with age-matched and young control subjects, with no differences between the latter groups. Both basal HSP72 (r = 0.75, P < 0.001) and HO-1 (r = 0.50,P < 0.05) mRNA expression correlated with the glucose infusion rate during the clamp. Significant correlations were also observed between HSP72 mRNA and both β-HAD (r = 0.61, P < 0.01) and CS (r = 0.65, P < 0.01). HSP72 mRNA was induced (P < 0.05) by the clamp in all groups. Although HO-1 mRNA was unaffected by the clamp in both the young and age-matched control subjects, it was increased (P < 0.05) ∼70-fold in the diabetic patients after the clamp. These data demonstrate that genes involved in providing cellular protection against oxidative stress are defective in patients with type 2 diabetes and correlate with insulin-stimulated glucose disposal and markers of muscle oxidative capacity. The data provide new evidence that the pathogenesis of type 2 diabetes involves perturbations to the antioxidant defense mechanism within skeletal muscle.

Keywords: euglycemic-hyperinsulinemic, HSP72, mRNA, diabete

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Authors: Yotaro Natani

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In his recent works, Frankfurt School theorist Axel Honneth elucidates an intersubjective notion of social freedom and outlines a vision of socialism as the realization of social freedom in the family, market economy, and public sphere. These arguments are part of his broader project of defending the tradition of immanent critique and normative reconstruction. In contrast, American Marxist sociologist Erik Olin Wright spells out a vision of socialism in terms of building real utopias -democratic, egalitarian, alternative institutions- through the exercise of civil society’s social power over the economy and state. Wright identifies ‘eroding capitalism’ as the framework for thinking about the strategic logics of gradually diminishing the dominance of capitalism. Both thinkers envision the transition toward socialism in terms of democratic experimentation; Honneth is more attentive to the immanent norms of social life, whereas Wright is better aware of the power of antagonistic structures. This paper attempts to synthesize the ideas of Honneth and Wright. It will show that Honneth’s critique of capitalism suffers from certain ambiguities because he attributes normative legitimacy to existing institutions, resulting in arguments that do not problematize aspects of capitalist structures. This paper will argue that incorporating the notion of power and thematizing the erosion of capitalism as a long-term goal for socialist change will allow Honneth to think more precisely about the conditions for realizing social freedom, in a manner that is still consistent with the immanent critique tradition. Such reformulation will result in a concept of social freedom that is less static and rooted in functional teleology and more oriented toward creative agency and experimental democracy.

Keywords: Axel Honneth, immanent critique, real utopias, social freedom, socialism

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Authors: Jorge Martinez, Brandon Roberts, Holly Payton Toca

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Background: Therapeutic hypothermia (TH) is the international standard of care for all comatose patients after cardiac arrest, but criticism focuses on poor outcomes. We sought to develop criteria to identify American urban patients more likely to benefit from TH. Methods: Retrospective chart review of 107 consecutive adults undergoing TH in downtown New Orleans from 2010-2014 yielded records for 99 patients with all 44 survivors or families contacted up to four years. Results: 69 males and 38 females with a mean age of 60.2 showed 63 dead (58%) and 44 survivors (42%). Presenting cardiac rhythm was divided into shockable (Pulseless Ventricular Tachycardia, Ventricular Fibrillation) and non-shockable (Pulseless Electrical Activity, Asystole). Presenting in shockable rhythms with ROSC <20 minutes were 21 patients with 15 (71%) survivors (p=.001). Time >20 minutes until ROSC in shockable rhythms had 5 patients with 3 survivors (78%, p=0.001). Presenting in non-shockable rhythms with ROSC <20 minutes were 54 patients with 18 survivors (33%, p=.001). ROSC >20 minutes in non-shockable rhythms had 19 patients with 2 survivors (8%, p=.001). Survivors of shockable rhythms showed 19 (100%) living post TH. 15 survivors (79%, n=19, p=.001) had CPC score 1 or 2 with 4 survivors (21%, n=19) having a CPC score of 3. A total of 25 survived non-shockable rhythm. Acute survival of patients with non-shockable rhythm showed 18 expired <72 hours (72%, n=25) with long-term survival of 4 patients (5%, n=74) and CPC scores of 1 or 2 (p=.001). Interestingly, patients with time to ROSC <20 minutes exhibiting more than one loss of sustained ROSC showed 100% mortality (p=.001). Patients presenting with shockable >20 minutes ROSC had overall survival of 70% (p=.001), but those undergoing >3 cardiac rhythm changes had 100% mortality (p=.001). Conclusion: Patients presenting with shockable rhythms undergoing TH had overall acute survival of 70% followed by long-term survival of 100% after 4 years. In contrast, patients presenting with non-shockable rhythm had long-term survival of 5%. TH is not recommended for patients presenting with non-shockable rhythm and requiring greater than 20 minutes for restoration of ROSC.

Keywords: cardiac rhythm changes, Pulseless Electrical Activity (PEA), Therapeutic Hypothermia (TH)

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Authors: Manfred Szerencsits, Christine Weinberger, Maximilian Kuderna, Franz Feichtinger, Eva Erhart, Stephan Maier

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Cover or catch crops have beneficial effects for soil, water, erosion, etc. If harvested, they also provide feedstock for biogas without competition for arable land in regions, where only one main crop can be produced per year. On average gross energy yields of approx. 1300 m³ methane (CH₄) ha^-1 can be expected from 4.5 tonnes (t) of cover crop dry matter (DM) in Austria. Considering the total energy invested from cultivation to compression for biofuel use a net energy yield of about 1000 m³ CH₄ ha^-1 is remaining. With the straw of grain maize or Corn Cob Mix (CCM) similar energy yields can be achieved. In comparison to catch crops remaining on the field as green manure or to complete fallow between main crops the effects on soil, water and climate can be improved if cover crops are harvested without soil compaction and digestate is returned to the field in an amount equivalent to cover crop removal. In this way, the risk of nitrate leaching can be reduced approx. by 25% in comparison to full fallow. The risk of nitrous oxide emissions may be reduced up to 50% by contrast with cover crops serving as green manure. The effects on humus content and erosion are similar or better than those of cover crops used as green manure when the same amount of biomass was produced. With higher biomass production the positive effects increase even if cover crops are harvested and the only digestate is brought back to the fields. The ecological footprint of arable farming can be reduced by approx. 50% considering the substitution of natural gas with CH₄ produced from cover crops.

Keywords: biogas, cover crops, catch crops, land use competition, sustainable agriculture

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Authors: Titanilla Komenda

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Human-machine-collaboration defines a direct interaction between humans and machines to fulfil specific tasks. Those so-called collaborative machines are used without fencing and interact with humans in predefined workspaces. Even though, human-machine-collaboration enables a flexible adaption to variable degrees of freedom, industrial applications are rarely found. The reasons for this are not technical progress but rather limitations in planning processes ensuring safety for operators. Until now, humans and machines were mainly considered separately in the planning process, focusing on ergonomics and system performance respectively. Within human-machine-collaboration, those aspects must not be seen in isolation from each other but rather need to be analysed in interaction. Furthermore, a simulation model is needed that can validate the system performance and ensure the safety for the operator at any given time. Following on from this, a holistic simulation model is presented, enabling a simulative representation of collaborative tasks – including both, humans and machines. The presented model does not only include a geometry and a motion model of interacting humans and machines but also a numerical behaviour model of humans as well as a Boole’s probabilistic sensor model. With this, error scenarios can be simulated by validating system behaviour in unplanned situations. As these models can be defined on the basis of Failure Mode and Effects Analysis as well as probabilities of errors, the implementation in a collaborative model is discussed and evaluated regarding limitations and simulation times. The functionality of the model is shown on industrial applications by comparing simulation results with video data. The analysis shows the impact of considering human factors in the planning process in contrast to only meeting system performance. In this sense, an optimisation function is presented that meets the trade-off between human and machine factors and aids in a successful and safe realisation of collaborative scenarios.

Keywords: human-machine-system, human-robot-collaboration, safety, simulation

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Authors: Tekle Olbamo, Tegegn Tesfaye, Dikaso Unbushe, Belete Jorga

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Bovine trypanosomosis is a haemoprotozoan parasitic disease, mostly transmitted by the tsetse fly (Glossina species) and poses significant losses to the livestock industry in pastoral and agro-pastoral areas. Therefore, the current study was aimed to determine the prevalence of bovine trypanosomosis and its vectorial density in some selected tsetse suppression and non-tsetse suppression areas of South Omo Zonefrom December 2018- November 2019. Dark phase contrast buffy coat, hematocrit techniques, and thin blood smear method were used for determination of prevalence and packed cell volume of trypanosomosis infection, respectively. For entomological investigation, 96 NGU traps were deployed (64 traps in tsetse suppression areas, 32 traps in tsetse non-suppression areas) in vector breeding areas. The overall prevalence of bovine trypanosomosis was 11.05% (142/1284), and overall seasonal prevalence of disease was 14.33% (92/642) and 7.78% (50/642) for dry and wet seasons, respectively. There was a statistically significant difference (P <0.05) in disease prevalence between the two seasons. Trypanosomacongolensewas the dominant parasite species; 80% and 71.64%, followed by Trypanosomavivax. Overall mean packed cell volume indicated parasitaemic animals (23.57±3.13) had significantly lower PCV than aparasitaemic animals (27.80±4.95), and animals examined during dry season (26.22±4.37) had lower mean PCV than animals examined during wet season with the significant association. Entomological study result revealed a total of 2.64 F/T/D and 2.03 F/T/D respectively from tsetse suppression areas and tsetse non-suppression areas during dry season and 0.42 F/T/D and 0.56 F/T/D during the wet season. Glossinapallidipes was the only cyclical vectors collected and identified from current study areas along with numerous mechanical vectors of genus Tabanus, Stomoxys, and Haematopota. Therefore integrated and safe control and prevention effort should be engaged to uphold cattle production and productivity in the area.

Keywords: bovine trypanosomiasis, South Omo, tsetse fly density, epidemiological study

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Authors: Suraj Jena, Rabindra Kumar Panda

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The study region of the reported study was in Eastern India, having a sub-humid sub-tropical climate and sandy loam soil. The rainfall in this region has wide temporal and spatial variation. Due to lack of adequate surface water to meet the irrigation and household demands, groundwater is being over exploited in that region leading to continuous depletion of groundwater level. Therefore, there is an obvious urgency in reversing the depleting groundwater level through induced recharge, which becomes more critical under the climate change scenarios. The major goal of the reported study was to investigate the effects of climate change on groundwater recharge and subsequent adaptation strategies. Groundwater recharge was modelled using HELP3, a quasi-two-dimensional, deterministic, water-routing model along with global climate models (GCMs) and three global warming scenarios, to examine the changes in groundwater recharge rates for a 2030 climate under a variety of soil and vegetation covers. The relationship between the changing mean annual recharge and mean annual rainfall was evaluated for every combination of soil and vegetation using sensitivity analysis. The relationship was found to be statistically significant (p<0.05) with a coefficient of determination of 0.81. Vegetation dynamics and water-use affected by the increase in potential evapotranspiration for large climate variability scenario led to significant decrease in recharge from 49–658 mm to 18–179 mm respectively. Therefore, appropriate conjunctive use, irrigation schedule and enhanced recharge practices under the climate variability and land use/land cover change scenarios impacting the groundwater recharge needs to be understood properly for groundwater sustainability.

Keywords: Groundwater recharge, climate variability, Land use/cover, GCM

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Authors: Eric Lai, Sarah Lorger, David Eisinger, Richard Waugh

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Introduction: Percutaneous embolization of varicoceles has shown similar outcomes to surgery. However, there are advantages of radiological intervention as patients are not exposed to general anaesthesia, experience a quicker recovery and face a lower risk of major complications. Radiological interventions are also preferable after a failed surgical approach. We evaluate clinical outcomes of percutaneous embolization at a tertiary hospital in Sydney, Australia. Methods: Retrospective case series without a control group from a single site (Royal Prince Alfred Hospital, Sydney, Australia). A data search was performed on the interventional radiology database with the word “varicocele” between February 2017 and March 2022. 62 patients were identified. Each patient file was reviewed and included in the study if they met the inclusion criteria. Results: A total of 56 patients were included. 6 patients were excluded as they did not receive intervention after the initial diagnostic venography. Technical success was 100%. Complications were seen in 3 patients (5.3%). The complications included post-procedural pain and fever, venous perforation with no clinical adverse outcome, and a mild allergic reaction to contrast. Recurrence occurred in 3 patients (5.6%), all of whom received a successful second procedure. DISCUSSION: This study demonstrates comparable rates of technical success, complication rate and recurrence to other studies in the literature. When compared to surgical outcomes, the results were also similar. The main limitation is multiple patients lack long-term follow-up beyond 1 year, resulting in potential underestimation of the recurrence rate. Conclusion: Percutaneous embolization of varicocele is a safe alternative to surgical intervention.

Keywords: varicocele, interventional radiology, urology, radiology

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Authors: Monika Michałowska, Anna Alichniewicz

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Detrimental outcomes of advanced maternal age on the chances of fertilization, pregnancy as well as mother and fetus health have been recognized for several decades. It seemed interesting to investigate whether there is a comparable awareness of the detrimental influence on the reproductive outcomes of late fatherhood, given that it has been already ten years since an intense and growing interest concerning later-age fatherhood commenced in medical research. To address that issue a two-step research was done. First, we performed a review of the subject literature to answer the following questions: 1) What age is defined as advanced?; 2) Is the same age defined as advanced in both genders?; 3) What terminology concerning age issues is used?; 4) Is the same age terminology used regarding both genders? The second part of our studies was devoted to the views of medical students. This part of our research comprised both quantitative and qualitative studies. Opinions of medical students in one of the Polish medical universities on several issues connected with assisted reproduction technology (ART) were gathered: 1) students’ attitude to in vitro fertilization (IVF) for women over 40 and for postmenopausal women; 2) students’ attitude to late fatherhood; 3) students’ reasoning given against acceptability of IVF procedure for all of these group of patients involved in an IVF procedure. Our analyses revealed that: First, there is no universal definition of the term ‘advanced age’; secondly, there is a general tendency to adopt different age limits depending on whether they refer to maternal or paternal age, but no justification is provided by the researchers explaining why they set different age limits for women and men; thirdly, the image of postponed fatherhood stands in stark contrast to postponed motherhood - while postponed fatherhood is frequently portrayed as a reasonable and conscious decision enabling a stable family environment for a child, the reasonableness of postponed motherhood is often questioned; finally, the bias regarding maternal versus paternal age is deeply embedded in medical students’ attitude to IVF for women over 40 and for postmenopausal women.

Keywords: gender stereotypes, reproductive medicine, maternal age, paternal age

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Authors: Mustafa Al-Yaseen, Haider Mohammed Mahdi, Haider Ali Al–Zahid, Nazar S. Haddad

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Background: Early diagnosis of musculoskeletal infections is of vital importance to avoid devastating complications. There is no single laboratory marker which is sensitive and specific in diagnosing these infections accurately. White blood cell count, erythrocyte sedimentation rate, and C-reactive protein are not specific as they can also be elevated in conditions other than bacterial infections. Materials Culture and sensitivity is not a true gold standard due to its varied positivity rates. Serum Procalcitonin is one of the new laboratory markers for pyogenic infections. The objective of this study is to assess the value of PCT in the diagnosis of soft tissue, bone, and joint infections. Patients and Methods: Patients of all age groups (seventy-four patients) with a diagnosis of musculoskeletal infection are prospectively included in this study. All patients were subjected to White blood cell count, erythrocyte sedimentation rate, C-reactive protein, and serum Procalcitonin measurements. A healthy non infected outpatient group (twenty-two patients) taken as a control group and underwent the same evaluation steps as the study group. Results: The study group showed mean Procalcitonin levels of 1.3 ng/ml. Procalcitonin, at 0.5 ng/ml, was (42.6%) sensitive and (95.5%) specific in diagnosing of musculoskeletal infections with (positive predictive value of 87.5% and negative predictive value of 48.3%) and (positive likelihood ratio of 9.3 and negative likelihood ratio of 0.6). Conclusion: Serum Procalcitonin, at a cut – off of 0.5 ng/ml, is a specific but not sensitive marker in the diagnosis of musculoskeletal infections, and it can be used effectively to rule in the diagnosis of infection but not to rule out it.

Keywords: procalcitonin, infection, labratory markers, musculoskeletal

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Authors: Choki, Supatchai Boonpratham, Suwannee Luppanapornlarp

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The objective of this study was to find a correlation between cephalometric measurements and visual perception of facial profile in skeletal type II patients. In this study, 250 lateral cephalograms of female patients from age, 20 to 22 years were analyzed. The profile outlines of all the samples were hand traced and transformed into silhouettes by the principal investigator. Profile ratings were done by 9 orthodontists on Visual Analogue Scale from score one to ten (increasing level of convexity). 37 hard issue and soft tissue cephalometric measurements were analyzed by the principal investigator. All the measurements were repeated after 2 weeks interval for error assessment. At last, the rankings of visual perceptions were correlated with cephalometric measurements using Spearman correlation coefficient (P < 0.05). The results show that the increase in facial convexity was correlated with higher values of ANB (A point, nasion and B point), AF-BF (distance from A point to B point in mm), L1-NB (distance from lower incisor to NB line in mm), anterior maxillary alveolar height, posterior maxillary alveolar height, overjet, H angle hard tissue, H angle soft tissue and lower lip to E plane (absolute correlation values from 0.277 to 0.711). In contrast, the increase in facial convexity was correlated with lower values of Pg. to N perpendicular and Pg. to NB (mm) (absolute correlation value -0.302 and -0.294 respectively). From the soft tissue measurements, H angles had a higher correlation with visual perception than facial contour angle, nasolabial angle, and lower lip to E plane. In conclusion, the findings of this study indicated that the correlation of cephalometric measurements with visual perception was less than expected. Only 29% of cephalometric measurements had a significant correlation with visual perception. Therefore, diagnosis based solely on cephalometric analysis can result in failure to meet the patient’s esthetic expectation.

Keywords: cephalometric measurements, facial profile, skeletal type II, visual perception

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Authors: Suraya Mohamad Nadzir, Badrol Ahmad, Norlia Berahim

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T91 steel has been used as construction material for superheater tubes in sub-critical and super critical boiler. This steel was developed with higher creep strength property as compared to conventional low alloy steel. However, this steel is also susceptible to materials degradation due to its sensitivity to heat treatment especially Post Weld Heat Treatment (PWHT) after weld repair process. Review of PWHT process shows that the holding temperature may different from one batch to other batch of samples depending on the material composition. This issue was reviewed by many researchers and one of the potential solutions is the development of weld repair process without PWHT. This process is possible with the use of temper bead welding technique. However, study has shown the hardness value across the weld joint with exception of PWHT is much higher compare to recommended hardness value. Based on the above findings, a study to evaluate the microstructure and hardness changes of T91 weld joint after heating at 560°C at varying duration was carried out. This study was carried out to evaluate the possibility of self-tempering process during in-service period. In this study, the T91 weld joint was heat-up in air furnace at 560°C for duration of 50 and 150 hours. The heating process was controlled with heating rate of 200°C/hours, and cooling rate about 100°C/hours. Following this process, samples were prepared for the microstructure examination and hardness evaluation. Results have shown full tempered martensite structure and acceptance hardness value was achieved after 50 hours heating. This result shows that the thin component such as T91 superheater tubes is able to self-tempering during service hour.

Keywords: T91, weld-joint, tempered martensite, self-tempering

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