Numerical investigation of fluid flow and heat transfer effects in minichannels and microchannels under h2 boundary condition

Deviations in heat transfer predictions by classical theory for single-phase laminar flow in microchannels have been mainly attributed to surface roughness, deviations in channel dimensions, errors in measurement, entrance and exit effects. Identifying correct thermal boundary conditions in a given application also plays an important role in accurate estimation of heat transfer coefficients. Different thermal boundary conditions generally applied in fluid domain are: T, H1, and H2. However, there are very few solutions available for the heat transfer under the H2 boundary condition which is the most applicable thermal boundary condition in many microchannel heat exchangers. The current work aimed at addressing two outstanding issues in this field: (i) predicting heat transfer rate in rectangular channels under H2 boundary conditions, and (ii) numerically studying the effects of structured roughness on pressure drop and heat transfer. A numerical model is developed to predict accurate fluid flow and heat transfer effects in microchannels under H2 boundary condition. Numerical data sets are generated for rectangular microchannels with different heated wall configurations. Although the results are seen as relevant in microscale applications, they are applicable to any sized channels. Based on the numerical results obtained for a wide range of aspect ratios, generalized correlations for fully developed laminar Nusselt number as a function of channel aspect ratio are presented for all the cases. This information can provide better understanding and insight into the transport processes in the microchannels. Surface roughness effects in conventional ducts are minimal whereas for the micro-sized channel, the roughness effects needs to be taken into account for laminar flow. Developing a better insight of the fundamental effects of surface roughness in parallel plate microchannels is therefore essential. Based on various roughness characterization schemes, the effect of structured roughness elements for incompressible laminar fluid flow is analyzed and the proposed numerical model is extended to accurately predict the pressure drop and heat transfer coefficient in presence of roughness using CFD software, FLUENT. The results are compared with the available experimental data for some of the rough surfaces

Bioprospecting and Characterization of poly-β- hydroxyalkanoate (PHAs) producing Pseudomonas Spp. isolated from edible oil contaminated soil

Plastics have battle to biological breakdown that result in its accumulation in the environment. This accentuates the need to search for biodegradable polymer, which is readily disposable and degradable. Bacteria synthesize and accumulate polyhydroxy alkanote (PHA) as carbon source under limiting conditions of nutrients. Bioprospecting for poly-β-hydroxyalkanoate (PHA)-accumulating micro-organisms was carried out in edible oil contaminated soil of north Gujarat region. They were isolated in unbalanced culture medium (high carbon/nitrogen ratio) with various edible oil used as carbon source. PHAs producing bacteria were identified by staining with Sudan black and solubilising cellular components in sodium hypochlorite. Two bacterial strains isolated, screened and characterized from edible oil contaminated soil samples were selected due to their capacity of growing in the presence of edible oil and at the same time producing PHA. The isolates were identified by PCR of the 16S rDNA gene using universal primers. The isolates were Psudomonas aeruginosa and Pseudomonas fluorescence

Recovery and characterization of poly(3-Hydroxybutyric acid) synthesized in Staphylococcus epidermidis

Polyhydroxyalkanoates (PHA) are biodegradable polyesters accumulated intracellularly as energy resources by bacterial species. In this study, fermentation process for production of PHA is carried out using sesame oil as carbon source. We studied recovery of poly(3-hydroxybutyric acid) (PHB) from Staphylococcus epidermidis by sodium hypochlorite digestion method. Recovered PHB sample was estimated by UV spectrophotometer. PHB from S. epidermidis was characterized and by these findings, we examined purified PHB by differential scanning calorimeter (DSC), a thermo gravimetric analyzer (TGA), thin layer chromatography (TLC) and infrared spectroscopy (IR). The results of our analysis of PHB while comparing with commercial source suggest that in DSC melting temperature of PHB was 173.36°C, TGA thermo grams of PHB sample was at 296.91°C, on TLC plate; Rf value was calculated as 0.71 and finally IR spectrum of the compounds showed characteristics bands for the groups CH, C=O and C-O, indicating the presence of PHB in the production medium.Key words: Polyhydroxyalkanoates (PHA), poly(3-hydroxybutyric acid) (PHB), Staphylococcus epidermidis

A study on geospatial technology for detecting and mapping of Solenopsis mealybug (Hemiptera: Pseudococcidae) in cotton crop

Detection of crop stress is one of the major applications of remote sensing in agriculture. Many researchers have confirmed the ability of remote sensing techniques for detection of pest/disease on cotton. The objective of the present study was to evaluate the relation between the mealybug severity and remote sensing indices and development of a model for mapping of mealybug damage using remote sensing indices. The mealybug-infested cotton crop had a significantly lower reflectance (33%) in the near infrared region and higher (14%) in the visible range of the spectrum when compared with the non-infested cotton crop having near infrared and visible region reflectance of 48 % and 9% respectively. Multiple Linear regression analysis showed that there were varying relationships between mealybug severity and spectral vegetation indices, with coefficients of determination (r2) ranging from 0.63 to0.31. Model developed in this study for the mealybug damage assessment in cotton crop yielded significant relationship (r2=0.863) and was applied on satellite data of 21st September 2009 which revealed high severity of mealybug and it was low on 24th September 2010 which confirmed the significance of the model and can be used in the identification of mealybug infested cotton zones. These results indicate that remote sensing data have the potential to distinguish damage by mealybug and quantify its abundance in cotton

Study of intravenous ferric carboxy maltose in iron deficiency anemia in women attending gynecological clinic - safety and efficacy

Background: Several intravenous iron preparations are available for the treatment of iron deficiency anemia (IDA). Some of these require multiple small infusions to prevent labile iron reactions while iron dextran (DEX) is associated with a risk of potentially serious anaphylactic reactions. Ferric carboxymaltose (FCM), a nondextran intravenous iron, is an effective and a safe option which can be administered in high single doses without serious adverse effects.Methods: It was a prospective study including 150 women of age >18 years with a definitive diagnosis of IDA and Hemoglobin (Hb) between 7-10 gm% from December 2013 to October 2014.Out of these, eleven women were lost to follow up and were excluded from the study. Intravenous FCM (500-1000mg) was administered and the improvement in Hb levels and iron stores was assessed after 3 weeks of total dose infusion.Results: Out of 150, 139 women were included in the study. Most of the women were in the age group of 30-39 years (38.12%). Most of the patients (74.10%) had mild anemia. Mean Hb levels increased over a period of 3 weeks after FCM administration from 8.70±1.04 gm% to 11.07±1.02 gm% which was statistically significant. Other parameters like S.TIBC (Serum total iron binding capacity), S. Ferritin, S. Iron also suggested a significant improvement after FCM administration. No serious life threatening adverse events were observed with FCM.Conclusion: Intravenous FCM is an effective and a safe treatment option for IDA and has an advantage of single administration of high doses without serious adverse effects

Cultural context shapes the carbon footprints of recipes

Food systems are responsible for a third of global anthropogenic greenhouse gas emissions central to global warming and climate change. Increasing awareness of the environmental impact of food-centric emissions has led to the carbon footprint quantification of food products. However, food consumption is dictated by traditional dishes, the cultural capsules that encode traditional protocols for culinary preparations. Carbon footprint estimation of recipes will provide actionable insights into the environmental sustainability of culturally influenced patterns in recipe compositions. By integrating the carbon footprint data of food products with a gold-standard repository of recipe compositions, we show that the ingredient constitution dictates the carbon load of recipes. Beyond the prevalent focus on individual food products, our analysis quantifies the carbon footprint of recipes within the cultural contexts that shape culinary protocols. While emphasizing the widely understood harms of animal-sourced ingredients, this article presents a nuanced perspective on the environmental impact of culturally influenced dietary practices. Along with the grasp of taste and nutrition correlates, such an understanding can help design palatable and environmentally sustainable recipes. Systematic compilation of fine-grained carbon footprint data is the way forward to address the challenge of sustainably feeding an anticipated population of 10 billion.Comment: 37 pages (inclusive of Extended Figures and Supplementary Materials), 5 Main Figures, 6 Extended Figures, 3 Supplementary Figures, and 6 Supplementary Table

Livestock Depredation by Leopards, Associated Economic Losses, and Financial Compensation to Communities in Chhota Udepur District of Central Gujarat, India

Livestock depredation by large carnivores has been documented across the entire Indian subcontinent. The failure of managers to mitigate livestock losses in landscapes dependent on subsistence agriculture poses a threat to the conservation of carnivores. For much of Gujarat, a western Indian state characterized by extensive semi-arid habitats, the Indian leopard (Panthera pardus fusca) is considered an apex predator. Increasing regional leopard populations in response to protection efforts has led to more attacks on humans, along with an increase in rates of livestock depredation. In many cases, the regional forest department financially compensates livestock owners for depredation caused by leopards. Herein, we report on data we collected on leopard-caused livestock depredations in the Chhota Udepur district of Gujarat for 2019–2020. Between November 2020 and March 2021, we recorded 104 distinct cases of leopard depredations that resulted in 134 livestock mortalities. Most attacks occurred in the middle of the night, with the greatest frequency occurring between 2100 and 0400 hours (n = 53). Interestingly, livestock depredations by leopards appeared to occur more in the monsoon season (66%) than during the drier seasons (Fisher’s least significant difference [LSD], P \u3c 0.05). We also found that not everyone enduring losses to leopards received full compensation for the value of their animals. Livestock kept in corrals at night were more vulnerable to leopard attack (R2 = 38.6, P = 0.01) compared to free-ranging livestock foraging by day in farms and forests. We recommend that livestock compensation claims filed by communities be investigated and processed quickly and that compensation be based on fair value for domestic animals lost. To better understand the drivers of human–leopard conflict, we also encourage rigorous surveys of potential leopard prey species in forested areas adjacent to conflict hotspots as well as research to identify the most effective methods communities might use to safeguard their livestock

Sloth Bear Attacks on Humans in Central India: Implications for Species Conservation

Conflicts with wild animals are increasing as human populations grow and related anthropogenic activities encroach into wildlife habitats. A good example of this situation is the increase in conflicts between humans and sloth bears (Melursus ursinus) in India. Sloth bears are known for their aggressive and unpredictable behavior. More human fatalities and injuries have been attributed to sloth bear attacks than all recorded incidences of wildlife attacks in Buldhana Forest Division of Maharashtra, India. We interviewed 51 victims that were attacked by sloth bears between 2009-2017 to better understand the reasons for the attacks. Thirty-four of the attacks (66.7%) resulted in serious injuries, and there were 7 human mortalities (13.7%) reported. Most attacks occurred close to agricultural fields (66.7%) and during midday (1100–1400 hours). More attacks (64.7%) occurred when a person was working or resting in the field, or retrieving water for the field followed by attacks while watching over grazing livestock (13.7%). Individuals aged 31 to 40 years (35.3%) were the most common victims of sloth bear attacks. Half of the attacks were during monsoon season (July to October, 51%) followed by summer (March to June, 35%) and winter (November to February, 14%). In 39% of cases, a single bear was involved while females with 2 cubs were found to be involved in 37% of attacks. This research was incorporated into a comprehensive conflict mitigation plan, which included field staff training for monitoring sloth bear population, formulation of a Rapid Rescue Unit to manage conflict situations, and sloth bear education programs in the high conflict villages. People were made aware of the behavior and activity pattern of sloth bears and preventive measures to mitigate potential conflicts

Effect of seizure timing on long-term survival in patients with brain tumor

OBJECTIVE: Seizures often occur in patients with primary brain tumor (BT). The aim of this study was to determine if there is an association between the time of occurrence of seizures during the course of BT and survival of these patients. METHODS: This retrospective cohort study at Henry Ford Hospital, an urban tertiary referral center, included all patients who were diagnosed with primary BTs at Henry Ford Health System between January 2006 and December 2014. Timing of seizure occurrence, if occurred at presentation or after the tumor diagnosis during follow-up period, in different grades of BTs, and survival of these patients were analyzed. RESULTS: Of the 901 identified patients, 662 (53% male; mean age: 56 years) were included in final analysis, and seizures occurred in 283 patients (43%). Patients with World Health Organization (WHO) grade III BT with seizures as a presenting symptom only had better survival (adjusted hazard ratio (HR): 0.27; 95% confidence interval (CI), 0.11-0.67; P = 0.004). Seizures that occurred after tumor diagnosis only (adjusted HR: 2.11; 95% CI, 1.59-2.81; P \u3c 0.001) in patients with WHO grade II tumors (adjusted HR: 3.41; 95% CI, 1.05-11.1; P = 0.041) and WHO grade IV tumors (adjusted HR: 2.14; 95% CI, 1.58-2.90; P \u3c 0.001) had higher mortality. Seizures that occurred at presentation and after diagnosis also had higher mortality (adjusted HR: 1.34; 95% CI, 1.00-1.80; P = 0.049), in patients with meningioma (adjusted HR: 6.19; 95% CI, 1.30-29.4; P = 0.021) and grade III tumors (adjusted HR: 6.19; 95% CI, 2.56-15.0; P \u3c 0.001). CONCLUSION: Seizures occurred in almost half of the patients with BTs. The association between seizures in patients with BT and their survival depends on the time of occurrence of seizures, if occurring at presentation or after tumor diagnosis, and the type of tumor. Better survival was noted in patients with WHO grade III BTs who had seizures at presentation at the time of diagnosis, while higher mortality was noted in WHO grade II tumors who had seizure at presentation and after tumor diagnosis, and in grade IV tumors after tumor diagnosis

Generation of Ultra-stable Pickering Microbubbles via Poly alkylcyanoacrylates

A range of solution conditions (pH, surfactant concentration and type) have been tested for the polymerization of alkyl cyanoacrylates (ethyl (ECA), butyl (BCA) and octyl (OCA)) into nanoparticles (NPs) potentially capable of stabilizing highly unstable microbubbles (MBs) of air in aqueous solutions. The optimum system was butyl cyanoacrylate (BCA) polymerized into PBCA particles at pH 4 in the presence of 1 wt.% Tyloxapol surfactant. These PBCA particles were highly effective at stabilizing MBs of only a few microns in size for at least 2 months. Microscopy over a range of length scales clearly indicated that these particles were stabilized via a Pickering mechanism. Only a relatively low volume fraction (ca. 1 vol.%) of MBs could be obtained via a single aeration step of a 0.7 wt.% dispersion of PBCA particles in a high shear mixer. Although this could be increased to 2 and 3 vol.% by second and third aerations, this reflects the difficulty of obtaining and maintaining rapid enough particle coverage of small bubbles even under turbulent conditions. Similar sizes and yields of PBCA particles could be obtained in the absence of surfactants, but these particles, with or without addition of surfactant afterwards, could not stabilize MBs. We estimate that approximately one quarter of the Tyloxapol when present during polymerization is incorporated into the particles on polymerization, which somehow imparts the correct surface hydrophobicity and contact angle to the particles at the A/W interface, making such particles so very effective as Pickering MB stabilizers