Stresses in an Isotropic Elastic Plate in the Form of Pascal's Limacon under Concentrated Forces

The problem of a thin elastic plate in the form of Pascal's limacon under concentrated forces at the extremeties of its axis has been solved by using complex variable technique. The solution has been obtained in a closed form. Stress components have been found out. In particular, the solution of an elastic circular plate and that of a plate in the form of a cardioid have been discussed. The variation of stress-intensity factor has been studied

Isolation and Characterization of the Endophytic N2 – Fixing Bacterium, Acetobacter Diazotrophicus aAssociated with Sugarcane Plants

Acetobacter  diazotrophicus is an obligate endophytic N2- fixing bacterium mainly associated with sugarcane and other sugar-rich plants that are propagated vegetatively (Kirchhof et al., 1998). This bacterium does not survive in soil or in weeds found in cane fields (Dobereiner, 1995) ). The presence of this endophyte within the tissues of sugarcane plants no doubt supplements the N-nutrition of the crop. This plants, preliminary work, thus attempts, for the first time, to isolate and characterize endophytes within the tissues of sugarcane plants grown in Kenana Sugar Company

Relación entre el hematocrito y algunos parámetros biológicos del sábalo de la India, Tenualosa ilisha (Familia Clupeidae)

Haematological parameters have been recognised as valuable tools for the monitoring of fish health. Here we analyse the relationship between haematocrit and body length, sex and reproductive state in the Indian Shad Tenualosa ilisha. Haematocrit value showed a quadratic relationship to fish size (body length), incrementing as the fish body length increased up to 400 mm, after which it decreased. Male fish showed a higher haematocrit value than females. Haematocrit appeared to be higher in the pre–spawning period than in the spawning phase, but then increased slightly in the post–spawning period.Se ha demostrado que los parámetros hematológicos constituyen una valiosa herramienta para controlar la salud de los peces. En este artículo se analiza la relación entre el hematocrito y la longitud del cuerpo, el sexo y el estado reproductivo del sábalo de la India Tenualosa ilisha. Se ha encontrado una relación cuadrática entre el valor del hematocrito y el tamaño del pez (longitud del cuerpo), en aumento con la longitud del cuerpo, hasta los 400 mm, para después empezar a disminuir. Los valores del hematocrito de los peces machos son más elevados que los de las hembras. Parece que el hematocrito es más elevado en el periodo anterior al desove que durante el mismo, aunque en el período posterior se registra un ligero aumento

Root cause analysis (RCA) of fractured ASTM A53 carbon steel pipe at oil & gas company

Incident involving failures of ASTM A53 carbon steel (CS) pipe, connected to pressure safety valve (PSV) and carrying raw gas has caused serious supply disruption. This study was performed to identify the most probable cause of the pipe failure. It was conducted by reviewing the existing design, construction data and pipe material analysis using non-destructive techniques such as VT, PT, MT and UT along with metallographic, hardness and microscopic analysis. The investigation revealed that excessive material loss has occurred in both failure and its adjacent regions due to abrasive grinding, resulting in the formation of a through thickness flaw. These grindings were performed to accommodate the pre-installed piping spool to avoid alteration in the pipe position. RCA demonstrated that this rapid thinning of the steel pipe body later led to its failure. Metallurgical study using photomicrograph shows that the morphology of the steel material was consistent and did not show any evidence of internal corrosion or micro fractures. Further damage to the surface of already excessively reduced thickness occurred due to nominal pipe vibration and atmospheric effect during service. The research work described in the paper has a significant meaning to recognize the root cause of such failures in CS pipes and through given recommendations to eliminate future such happenings

Agro-Morphological, Yield and Quality Traits and Interrelationship with Yield Stability in Quinoa (Chenopodium quinoa Willd.) Genotypes under Saline Marginal Environment

Quinoa (Chenopodium quinoa Willd.) is a halophytic crop that shows resistance to multiple abiotic stresses, including salinity. In this study we investigated the salinity tolerance mechanisms of six contrasting quinoa cultivars belonging to the coastal region of Chile using agro-physiological parameters (plant height (PH), number of branches/plant (BN), number of panicles/plant (PN), panicle length (PL), biochemical traits (leaf C%, leaf N%, grain protein contents); harvest index and yield (seed yield and plant dry biomass (PDM) under three salinity levels (0, 10, and 20 d Sm-1 NaCl). The yield stability was evaluated through comparision of seed yield characteristics [(static environmental variance (S-2) and dynamic Wricke's ecovalence (W-2)]. Results showed that significant variations existed in agro-morphological and yield attributes. With increasing salinity levels, yield contributing parameters (number of panicles and panicle length) decreased. Salt stress reduced the leaf carbon and nitrogen contents. Genotypes Q21, and AMES13761 showed higher seed yield (2.30 t ha(-1)), more productivity and stability at various salinities as compared to the other genotypes. Salinity reduced seed yield to 44.48% and 60% at lower (10 dS m(-1)) and higher salinity (20 dS m(-1)), respectively. Grain protein content was highest in NSL106398 and lowest in Q29 when treated with saline water. Seed yield was positively correlated with PH, TB, HI, and C%. Significant and negative correlations were observed between N%, protein contents and seed yield. PH showed significant positive correlation with APL, HI, C% and C:N ratio. HI displayed positive correlations with C%, N% and protein content., All measured plant traits, except for C:N ratio, responded to salt in a genotype-specific way. Our results indicate that the genotypes (Q21 and AMES13761) proved their suitability under sandy desert soils of Dubai, UAE as they exhibited higher seed yield while NSL106398 showed an higher seed protein content. The present research highlights the need to preserve quinoa biodiversity for a better seedling establishment, survival and stable yield in the sandy desertic UAE environment

Effects of Allium sativum in cardiovascular diseases: A Review

Epidemiologic studies show an inverse correlation between garlic consumption and progression of cardiovascular disease. Cardiovascular disease is associated with multiple factors such as raised serum total cholesterol, raised LDL and an increase in LDL oxidation, increased platelet aggregation, hypertension, and smoking. Numerous in vitro studies have confirmed the ability of garlic to reduce these parameters. Thus, garlic has been shown to inhibit enzymes involved in lipid synthesis, decrease platelet aggregation, prevent lipid peroxidation of oxidized erythrocytes and LDL, increase antioxidant status, and inhibit angiotensin-converting enzyme. These findings have also been addressed in clinical trials. The studies point to the fact that garlic reduces cholesterol, inhibits platelet aggregation, reduces blood pressure, and increases antioxidant status. Since 1993, 44% of clinical trials have indicated a reduction in total cholesterol, and the most profound effect has been observed in garlic's ability to reduce the ability of platelets to aggregate. Mixed results have been obtained in the area of blood pressure and oxidative-stress reduction. The findings are limited because very few trials have addressed these issues. The negative results obtained in some clinical trials may also have resulted from usage of different garlic preparations, unknown active constituents and their bioavailability, inadequate randomization, selection of inappropriate subjects, and short duration of trials. This review analyzes in vitro and in vivo studies published since 1993 and concludes that although garlic appears to hold promise in reducing parameters associated with cardiovascular disease, more in-depth and appropriate studies are required. Keywords: Allium sativum, hypercholesterolemia, antioxidants, cardioprotective, HMG-CoA reductase

Vitamin D Deficiency in HCV Antiviral Treatment Responders versus Non-Responders

Background: Hepatitis C virus (HCV) is a major cause of chronic liver disease (CLD). Pakistan has a high burden of infectious diseases, including HCV. Its prevalence varies according to geographic regions in the country from about 2·4% to 6·5%. The objective of the study was to compare the frequency of vitamin D deficiency in responders and non-responders of antiviral treatment for chronic hepatitis C.Material and Methods: This comparative cross-sectional study was conducted in Hepatitis Clinic, Jinnah hospital, Lahore from 20th May to 20th November 2013. After ethical approval, participants were selected by using purposive non-probability sampling, 52 responder patients i.e. who were labeled negative for HCV RNA by PCR after 12 weeks of antiviral treatment and 52 non-responder patients were included in this study. Data was collected by using pretested structured questionnaire. Vitamin D3 levels were measured by ELISA and a cut-off value of below 30ng/ml was labeled as Vitamin D deficiency. SPSS version 21 was used to analyze data with p value less than 0.05 taken as statistically significant.Results: Out of 104 patients (mean age 35±8.1 years), 61.5% were males and 38.5 % were females. There was a significant difference in frequency of vitamin D deficiency in treatment responder group when compared to non-responders (p = 0.016). Mean level of vitamin D was 21.8±10.8ng/ml in responders whereas it was 15.6±7.5 in non-responders with a statistically significant difference (p = 0.001).Conclusion: This study concludes that there is a significant vitamin D deficiency among treatment non-responders as compared to treatment responders in patients with chronic hepatitis C

A New Class of Electrocatalyst Materials for Direct Methanol Fuel Cell Applications

Direct methanol fuel cell (DMFC) has been attracting lots of attention as a power source for transportation, stationary and portable electronic devices due to the high energy density of methanol and ease of handling compared to gaseous fuels such as hydrogen and natural gas. However, the commercialization of DMFC is still limited due to some technical challenges such as methanol crossover and low methanol electro-oxidation kinetics. In order for fuel cells to be a feasible and viable option amongst clean energy technologies, innovations in the materials developments are required for efficient operation of fuel cells. Many efforts have been made in various research laboratories to develop high-performance catalysts that will enhance the methanol electro-oxidation. Compared to any single-metal catalyst, Pt has shown the highest activity for the electro-oxidation of methanol in an acid environment. However, Pt is expensive and during the methanol electro-oxidation reaction, COads and other organic intermediates such as formaldehyde, formic acid and methyl formate are formed on the Pt surface, which results in poisoning of the Pt catalyst. Many binary and ternary catalysts for methanol electro-oxidation have been investigated and reported in the literature, most of them based on modification of Pt with some other metal(s). The aim is to accelerate the oxidation of the intermediates and decrease their accumulation so as to improve the catalyst performance. Among the various catalyst formulations, PtRu alloy has shown the best results for the methanol electro-oxidation. Diverse methods have been used to prepare the PtRu-based catalysts for methanol electro-oxidation. Catalyst composition and method of preparation are known to immensely affect the physical property es and electrochemical performance of a catalyst. Thus, there is the need to use a carefully selected approach in order to prepare a catalyst with the highest attainable performance. Incorporation of transition metals into the PtRu catalysts to form ternary catalysts in order to improve the performance of the PtRu catalysts is one of the techniques attracting a lot of interest. In this work, a novel approach have been used for synthesizing a new class of electrocatalyst nanomaterials for electro-oxidation of methanol by incorporation nano-oxides of transition metals. The prepared nanomaterial catalysts were characterized using FESEM, BET surface area, EDX, FT-IR and XRD. The catalysts performance was studied using cyclic voltammetry and compared with the commercial Pt-Ru/C.qscienc

Seroprevalence of Mycobacterium avium subsp. paratuberculosis in Dairy Cattle in Khartoum State, Sudan

Paratuberculosis, caused by Mycobacterium avium subspecies paratuberculosis (MAP), is a chronic wasting disease mainly of domestic and wild ruminants. It occurs worldwide, causing significant economic losses through decreased productivity, low fertility, increased cull rates and mortality. It is listed by the OIE (World Organization for Animal Health) as a disease of concern to trade in animals. Prevalence of this disease can be studied by detecting anti-MAP antibodies by Enzyme linked immunosorbent Assay (ELISA). The aim of this study was to investigate the current prevalence of MAP infection in cattle in Khartoum State. The overall apparent prevalence of MAP infection was found to be 6.3% and 18.9% at animal and herd levels, respectively. All seropositive animals were cross-bred females of good body condition; most of them (>90%) were >3 years old and >50% were from medium-sized herds in Omdurman. No significant association (p > 0.05) was found between seropositivity and animal herd size. The prevalence of MAP infection in Khartoum State is still low to medium compared to other parts of the world, but it is comparable to those reported from other African countries. Further studies with the view of designing nationwide surveys in domestic ruminants and camels in other states of the country are needed for establishing control programmes

Can sulphur improve the nutrient uptake, partitioning, and seed yield of sesame?

Sulphur (S) is considered to improve the nutrient uptake of plants due to its synergistic relationship with other nutrients. This could ultimately enhance the seed yield of oilseed crops. However, there is limited quantitative information on nutrient uptake, distribution, and its associated impacts on seed yield of sesame under the S application. Thus, a two-year field study (2018 and 2019) was conducted to assess the impacts of different S treatments (S-0 = Control, S-20 = 20, S-40 = 40, and S-60 = 60 kg ha(-1)) on total dry matter production, nitrogen, phosphorus, potassium, S uptake and distribution at the mid-bloom stage and physiological maturity. Furthermore, treatment impacts were studied on the number of capsules per plant, number of seeds per capsule, thousand seed weight, and seed yield at physiological maturity in sesame. Compared to S-0, over the years, treatment S-40 significantly increased the total uptake of nitrogen, phosphorus, potassium, and S (by 13, 22, 11% and 16%, respectively) at physiological maturity, while their distribution by 13, 36, 14, and 24% (in leaves), 12, 15, 11, and 15% (in stems), 15, 42, 18, and 10% (in capsules), and 14, 22, 9, and 15% (in seeds), respectively. Enhanced nutrient uptake and distribution in treatment S-40 improved the total biomass accumulation (by 28%) and distribution in leaves (by 34%), stems (by 27%), capsules (by 26%), and seeds (by 28%), at physiological maturity, as compared to S-0. Treatment S-40 increased the number of capsules per plant (by 13%), number of seeds per capsule (by 11%), and thousand seed weight (by 6%), compared to S-0. Furthermore, over the years, relative to control, sesame under S-40 had a higher seed yield by 28% and enhanced the net economic returns by 44%. Thus, our results suggest that optimum S level at the time of sowing improves the nutrient uptake and distribution during the plant lifecycle, which ultimately enhances total dry matter accumulation, seed yield, and net productivity of sesame