Effect of Area Ratio on Base Pressure in a Suddenly Expanded Duct for Under Expanded Flow ft Mach 1.87

The results of an experimental investigation carried out to control the base pressure in a suddenly expanded axi-symmetric passage is presented in this paper. An active control in the form of micro jets is employed to control the base pressure. Air injection at four locations at the base, symmetric to the nozzle axis is used as the active control. The jet Mach number studied and the area ratios are 1.87, and 2.56, 3.24, 4.84, and 6.25. The L/D ratio is varied from 10 to 1. The experiments are conducted at a fixed level of under expansion (i.e. Pe/Pa = 1.5). In addition to base pressure, wall pressure field along the duct was also measured. As high as 80 percent increase in base pressure was achieved for certain combination of parameters of the present study. The minimum Length-todiameter ratio of the duct required is L/D = 2 for area ratios 6.25 and 4.84. Whereas, this requirement is L/D = 1 for area ratios 2.56 and 3.24

Nasal and hand carriage of bacteria in different groups of persons in a teaching hospital in India

275 persons of different categories were studiedfor nasal and hand carnage of different pathogenic bacteria. Overall carriage rate was 54.5%. Doc­tors and paramedical staff had higher bacterial carriage rate in comparison to other groups. Though Staphylococcus aureus iwu the commonest or­ganism isolated from both nose and skin, earners of Escherichia coli. Pseudomonas and Klebsiella group ofgramnegative bacilli was also observed. Nasal carrier were commonest than dermal carriag

Relative growth of harpiosquilla raphidea (Fabricius, 1798) (crustacea: stomatopoda) male and female populations

Morphometric analysis was carried out to find out changes in the growth pattern of male and female stomatopod, Harpiosquilla raphidea. Six morphometric relationships were examined on 105 males and 105 females, ranging in size from 103 to 207 mm and from 104 to 222 mm in total length, respectively. In both the sexes, the relative growth of carapace length, propodus length of raptorial claw and total weight in relation to total length was found positively allometric. Telson width in both the sexes and abdomen width in males showed slightly negative allometry, while the abdomen width of females showed slightly positive allometry, indicating some variation in the growth between sexes which could be attributed to the energy requirement for maturation in females. The propodus of females was also found to be bigger than that of males. It is quite interesting as males only have larger chela in other crustaceans. It has a functional significance in that it is of immense help at the time of intense feeding during maturation of oocytes which requires higher energy

Biofuel potential within chaetoceros species (bacillartophyceae) from coastal water of Pahang, Malaysia

Several marine diatoms have been known for their high lipid content. Chaetoceros is the largest genus of marine planktonic diatoms with approximately 400 species described. Lipid is important as primary storage for nutrient and essential for cell's growth and function. Nowdays, there are increasing in demands for alternative source of fuel with several attempts have been conducted to find the best ways for fatty acid collection and algae have been listed as potential source for lipid. This study was-aimed to analyze the production of fatty acids from marine algae Genus Chaetoceros. The results showed three species had been identified as Chaetoceros baculites, Chaetoceros anostomosans and Chaetoceros affinis var. willei. Chaetoceros baculites had higher growth rate compared to other species mention earlier. All species had more than 40o/o of total lipid detected during exponential phase of their growth. Based on accumulation, Chaetoceros baculites has higher lipid percentage than other species followed by Chaetoceros ffinis var. willei and lastly Chaetoceros anastomosans. This indicates that Genus Chaetoceros can be treated as potential sources biofuel industry in Malaysia

Prevalence of COVID-19 Vaccine Hesitancy in South Asia: A Systematic Review and Meta-Analysis

Vaccine uptake and coverage in susceptible populations are needed through effective vaccination campaigns to address the COVID-19 pandemic in South Asian countries. We aimed to measure the pooled proportion of COVID-19 vaccine hesitancy in this regard. Research articles published between January 1, 2020, to December 31, 2021, were searched through Medline, PubMed, Cochrane, Google Scholar, and the WHO COVID-19 database. The Joanna Briggs Institute (2014) tool for prevalence studies was used to assess data quality. We performed a meta-regression test and a sensitive analysis among the studies and used the DerSimonian and Laird random-effects model to measure the pooled effect estimates. Subgroup analyses were performed concerning vaccine hesitancy, countries, study population, study level, and the time since the first outbreak of the pandemic. A total of 43 studies out of 598 published articles across the eight countries in South Asia were included. The pooled proportion of COVID-19 vaccine hesitancy was 26.5% (95% CI [22, 31], I2 = 99.59%). Vaccine hesitancy was higher in Afghanistan (37%), Pakistan (33%), and Bangladesh (28.9%); among the general population (29%); at community levels (27.9%); and the duration of time of 1–12 months since the first outbreak in each country (27.5%). Vaccine hesitancy exists in South Asia with different rates among countries, population sub-groups, communities, study- levels, duration of time since the first outbreak, and study population. Therefore, enhancing public awareness of vaccination and vaccine hesitancy is required to prevent future pandemics

Isolation and characterization of soda lignin from OPEFB and evaluation of its performance as wood adhesive

The purpose of this study was to explore the mechanical properties of plywood panels that had been bound with lignin-phenol formaldehyde (LPF) resin. To do this lignin was extracted from oil palm empty fruit bunch (OPEFB) fiber by soda pulping method, and characterized by FT-IR,1 HNMR, and TGA analysis. Then, various compositions of soda lignin (10-50 wt %) was used as phenol substitute in lignin-based phenol-formaldehyde (PF) resin synthesis. The characteristics of the synthesized resin were compared to the properties of PF resin. Plywood was fabricated with LPF and its mechanical properties were studied and evaluated using industry standards. Increasing the substitution of phenol with soda lignin up to 40%, improves the mechanical properties of plywood. This research demonstrated that the lignin is used as a renewable replacement of phenol in PF resin synthesis

Bacterial pollution in Molluscs Arch Clam, Orbicularia orbiculata and Blood Cockle, Anadara granosa of Pahang estuary, Malaysia

A study was conducted on physico-chemical parameters and bacterial pollution in Orbicularia orbiculata (Wood, 1828) and Anadara granosa (L.) at Pahang estuary from January to February 2009. The temperature was ranged from 28.00-29.87°C, pH 7.79-8.10, specific conductivity 51.49-55.89 mS cm-1, salinity 18.74-30.10 ppt., TDS 33.63-39.59 g L-1, DO 6.80-7.50 mg L-1. The nitrate concentration was found to be highest at Station 3 (14.09 μg at N-l) and lowest at Station 2 (7.04 μg at N-l). The nitrite concentration showed highest concentration at Station 4 (7.07 μg at N-l) and lowest concentration at Station 2 (1.67 μg at N-l). Whilst the phosphate content was higher (10.78 μg at N-l) at Station 3 and lowest at Station 2 (2.34 μg at N-l). A total of 60 Orbicularia orbiculata and 40 Anadara granosa samples were subjected to microbiological analysis. The bacteria were isolated using non selective agar such as TSA agar and selective agar before they were identified using conventional methods in combination with API identification kit. A total of nine bacterial species were identified from Orbicularia orbiculata. They were Escherichia coli., Aerococcus viridans 1, Aerococcus viridans 2, Gemella morbillorum, Kocuria varians, Micrococcus sp., Pseudomonas aeruginosa, Staphylococcus sciuri, Streptococcus pneumoniae. Whilst, Nineteen bacterial species were identified in Anadara granosa such as Aeromonas hydrophila group 1, Aerococcus viridians 1, Aerococcus viridans 2, Chromobacterium violaceum., Enterobacter gergoviae, Erwinia sp., Escherichia coli, Enterococcus avium, Gemella morbillorum, Kluyvera sp., Vibrio fluvialis, Vibrio cholerae, Vibrio parahaemolyticus, Lactococcus lactis, Leuconostoc sp., Staphylococcus capitis, Staphylococcus lentus, Staphylococcus epidermidis, Staphylococcus xylosus. The finding indicates that the edible mollusc of Pahang estuary was polluted with pathogenic bacteria which could be harmful for human consumption

Diagnosed hematological malignancies in Bangladesh - a retrospective analysis of over 5000 cases from 10 specialized hospitals

Background The global burden from cancer is rising, especially as low-income countries like Bangladesh observe rapid aging. So far, there are no comprehensive descriptions reporting diagnosed cancer group that include hematological malignancies in Bangladesh. Methods This was a multi-center hospital-based retrospective descriptive study of over 5000 confirmed hematological cancer cases in between January 2008 to December 2012. Morphological typing was carried out using the “French American British” classification system. Results A total of 5013 patients aged between 2 to 90 years had been diagnosed with malignant hematological disorders. A 69.2% were males (n = 3468) and 30.8% females (n = 1545), with a male to female ratio of 2.2:1. The overall median age at diagnosis was 42 years. Acute myeloid leukemia was most frequent (28.3%) with a median age of 35 years, followed by chronic myeloid leukemia with 18.2% (median age 40 years), non-Hodgkin lymphoma (16.9%; median age 48 years), acute lymphoblastic leukemia (14.1%; median age 27 years), multiple myeloma (10.5%; median age 55 years), myelodysplastic syndromes (4.5%; median age 57 years) and Hodgkin’s lymphoma (3.9%; median age 36 years). The least common was chronic lymphocytic leukemia (3.7%; median age 60 years). Below the age of 20 years, acute lymphoblastic leukemia was predominant (37.3%), followed by acute myeloid leukemia (34%). Chronic lymphocytic leukemia and multiple myeloma had mostly occurred among older patients, aged 50-over. Conclusions For the first time, our study presents the pattern and distribution of diagnosed hematological cancers in Bangladesh. It shows differences in population distributions as compared to other settings with possibly a lower presence of non-Hodgkin lymphoma. There might be under-reporting of affected women. Further studies are necessary on the epidemiology, genetics and potential environmental risk factors within this rapidly aging country

A comparison of traditional diarrhoea measurement methods with microbiological and biochemical indicators : a cross-sectional observational study in the Cox's Bazar displaced persons camp

Background Water, Sanitation, and Hygiene (WASH) systems aim to reduce the spread of enteric pathogens, particularly amongst children under five years old. The most common primary outcome of WASH trials is carer-reported diarrhoea. We evaluate different diarrhoea survey instruments as proxy markers of enteric pathogen presence in stool. Methods We recruited 800 community-based participants from the Cox's Bazar Displaced Person's Camp in Bangladesh, split evenly between the rainy (July/August 2020) and dry (November/December 2020) periods. Participants were randomized evenly into either a standard survey asking carers if their child under five years old has had diarrhoea in the past fortnight, or a pictorial survey asking carers to pick from a pictorial chart which stools their child under five years old has had in the past fortnight. We collected stools from a random sub-sample of 120. Stools were examined visually, and tested for proteins associated with enteric infection and 16 enteric pathogens. We calculated sensitivities and specificities for each survey type, visual examination, and proteins with respect to enteric pathogen presence. Findings The sensitivity of the standard survey for enteric pathogen presence was 0.49[95%CI:0.32,0.66] and the specificity was 0.65[0.41,0.85]. Similar sensitivities and specificities were observed for pictorial survey, visual inspection, and proteins. Interpretation While diarrhoea is an important sign in clinical practice it appears that it is a poor proxy for enteric pathogen presence in stool in epidemiological surveys. When enteric infection is of interest, this should be measured directly

Optimizing IC engine efficiency: A comprehensive review on biodiesel, nanofluid, and the role of artificial intelligence and machine learning

Transportation and power generation have historically relied upon Internal Combustion Engines (ICEs). However, because of environmental impact and inefficiency, considerable research has been devoted to improving their performance. Alternative fuels are necessary because of environmental concerns and the depletion of non-renewable fuel stocks. Biodiesel has the potential to reduce emissions and improve sustainability when compared to diesel fuel. Several researchers have examined using nanofluids to increase biodiesel performance in internal combustion engines. Due to their thermal and physical properties, nanoparticles in a host fluid improve engine combustion and efficiency. This comprehensive review examines three key areas for improving ICE efficiency: biodiesel as an alternative fuel, application of nanofluids, and artificial intelligence (AI)/machine learning (ML) integration. The integration of AI/ML in nanoparticle-infused biodiesel offers exciting possibilities for optimizing production processes, enhancing fuel properties, and improving engine performance. This article first discusses, the benefits of biodiesel concerning the environment and various difficulties associated with its usage. The review then explores the effects and characteristics of nanofluids in IC engines, aiming to know their impact on engine emissions and performance. After that, this review discusses the utilization of AI/ML techniques in enhancing the biodiesel-nanofluid combustion process. This article sheds light on the ongoing efforts to make ICE technology more environmentally friendly and energy-efficient by examining current research and emerging patterns in these fields. Finally, the review presents the challenges and future perspectives of the field, paving the way for future research and improvement