76 research outputs found

    Numerical Study of Temperature and Stress Fields in Laser Cutting of Aluminium Alloy Sheet

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    AbstractDue to thermal nature of laser cutting, high temperature and thermal stresses are developed at the cut edge that affects finally the cut edge quality. This paper aims for developing a numerical simulation model to predict the temperature and residual stresses in the laser cutting of Aluminium alloy (Al-2024).The temperature and stress fields developed in cut section are predicted numerically using ANSYS finite element code. For the analysis, Fourier law of heat conduction and Gaussian distribution of a laser beam are considered. Temperature dependent thermo-physical properties of the material are used in numerical simulation. It is found that high temperature gradient exists at laser irradiated spot which results in high thermal stresses across the cut section. Also it has been found that the maximum temperature obtained during laser cutting is reduced with increasing laser scanning velocity. Stress distribution results shows that stresses attains low values at laser irradiated spot because of the reduction of thermal expansion coefficient with increasing temperature. The comparison of results based on numerical simulation with the mathematical model shows good agreements

    Avapritinib: novel hope for patients with metastatic gist with PDGFRA exon 18 mutation

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    Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms of the gastrointestinal tract associated with high rates of malignant transformation. The activating mutations in platelet-derived growth factor receptor A (PDGFRA) have been linked to the development of GISTs, and up to approximately 10% of GIST cases involve mutations of this gene. Current treatment options for metastatic GIST are minimal, mainly trusting on tyrosine kinase inhibitors (TKIs) such as Imatinib, Sunitinib and Regorafenib. However, eventually, most patients develop resistance to TKIs, usually due to the acquisition of secondary mutations. Moreover, 5-6% of patients with unresectable of metastatic GIST have the primary PDGFRA D842V mutation, which makes it resistant to all approved treatment options. Avapritinib, a potent and selective TKI of KIT and PDGFRA activation loop mutants. The drug demonstrates anti-tumor activity by inhibiting the autophosphorylation of KIT D816V and PDGFRA D842V, thereby terminating the downstream signalling. The drug is available in oral formulation with a recommended dosage of 300 mg once daily. The onset of Avapritinib is fast, shows rapid absorption and linear pharmacokinetics. Most common adverse reactions seen are edema, fatigue, abdominal pain, and neurocognitive defects. Clinical trials for Avapritinib have been positive, and results suggest that the drug may be a new safe and effective option for metastatic GIST treatment. With Blueprint Medicines having already received US FDA approval in January 2020, Avapritinib may soon be an addition to the mounting armoury of drugs against metastatic GIST harbouring PDGFRA exon 18 mutation

    Gene variants polymorphisms and uterine leiomyoma: an updated review

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    Uterine leiomyoma, commonly referred to as fibroids, is a benign tumor that develops in the muscular wall of the uterus. These growths are non-cancerous and can vary in size, ranging from tiny nodules to larger masses. Uterine leiomyomas often occur during a woman’s reproductive years and can lead to symptoms such as heavy menstrual bleeding, pelvic pain, and pressure on nearby organs. While the exact cause is not fully understood, hormonal factors, particularly estrogen and progesterone, are believed to play a role in their development. The exploration of connections between genetic variants and uterine leiomyoma has captivated scientific attention for numerous years. The results from investigations remain a subject of intrigue within the scientific community. To date, the findings regarding the relationships between single nucleotide polymorphisms (SNPs) and uterine leiomyoma have exhibited some inconsistencies. However, amidst these inconsistencies, several promising outcomes have emerged that hold the potential to shape future research endeavors. These promising leads could pave the way for the development of innovative targeted therapies and novel prognostic biomarkers. This review specifically centers on accentuating the existing literature data concerning genetic variants that have been explored for their potential connections to uterine leiomyoma. Additionally, it underscores the prospects of employing genetic variations as diagnostic and prognostic biomarkers for individuals diagnosed with uterine leiomyoma

    Nucleic acid drugs: a novel approach

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    Nucleic acid base sequence of proteins plays a crucial role in the expression of gene. The gene is responsible for the synthesis of proteins and these proteins, which are synthesized, are responsible for the biological process and also for dreadful diseases as well. Once if the nucleic acid sequence is altered, we would be able to block or transfer the message for protein synthesis, there by preventing the particular protein, which is responsible for the disease. These nucleic acids act as drugs by different mechanisms, they may bind with the synthesized proteins, and they can hybridize to a messenger RNA leading to translation arrest or may induce degradation to target RNA. In this way the nucleic acids act as drug for inhibiting gene expression or protein synthesis. This article examines about the different types of nucleic acid drugs, their mechanisms, advantages, drawbacks and their future prospects. Key Words: Aptamers, ribozymes, antisense oligonucleotides. African Journal of Biotechnology Vol.3(12) 2004: 662-66

    Machine Learning Based Maximum Power Prediction for Photovoltaic System

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    This manuscript proposes a data-driven machine learning algorithm to track maximum power for PV (photovoltaic) panel systems. Data from the PV panel system connected to a boost converter has been collected. PV Voltage, current, temperature, irradiance, PI and power value have been collected for the supervised machine learning-based modeling. Where PV Voltage, PV current, temperature, and irradiance are the predictors, and PI (proportional integral) is the response of the machine learning-based model. The proposed system becomes more efficient with time while existing MPPT (maximum power point tracking) work on a specific logic for whole life. The model efficacy has been analyzed based on accuracy, scattering plot, and ROC (receiver operating characteristics) curve

    Unveiling the spatial pattern and determinants of child anaemia in India: National family health survey-5 chronicles (NFHS-5)

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    Background/Aim: Childhood anaemia continues to persist as a prominent nutritional disease and a public health challenge in India despite several initiatives by the Government of India. This study aimed to identify predictors and regional disparities for targeted interventions. Methods: This study utilised data from a nationally representative cross-sectional survey from the fifth round of the National Family Health Survey (NFHS-5), encompassing 177,695 children aged 6-59 months across 707 districts and 36 states and union territories of India. It employed multivariate logistic regression and spatial analysis at district levels to examine socio-demographic predictors and spatial patterns of childhood anaemia in the country. Result: Multivariate logistic results revealed, women aged 15-19 were 2.43 times more likely to have an anaemic child compared to those aged 35-49 and uneducated mothers had a 29 % higher likelihood of having an anaemic child. There was positive spatial autocorrelation (Moran's I value = 0.579) at the district level in India, with 108 identified hotspots in regions including Jammu and Kashmir, Ladakh, Gujarat, Maharashtra, Telangana, Uttar Pradesh, Rajasthan, Jharkhand, Chhattisgarh and Bihar. The spatial error model (SEM) indicated that mother's anaemia (0.53) and maternal education (0.23) were key predictors of child anaemia in India. Conclusion: The study findings provide valuable understanding regarding the socio-demographic predictors associated with childhood anaemia such as adolescent motherhood, low education, lack of media exposure, higher birth order and rural residence. Also, the spatial study provides the spatial heterogeneity of childhood anaemia at the district level and advocates more attention toward hotspot regions in the country

    Formulations and evaluation of Cyclodextrin complexed Ceadroxil loaded nanosponges

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    Cefadroxil (CFD) is a broad spectrum antibiotic that acts against an extensive variety of bacteria, including Gram-positive and Gram-negative bacteria. The major drawback of orally administered drug like cefadroxil is its shorter half life of 1.2 hrs. The goal of the study is to prolong the drug release, producing a desired blood serum level, reduction in drug toxicity and improving the patient compliance by prolonging the dosing intervals. Cyclodextrin-based nanosponges (NS) are a novel class of cross-linked derivatives of cyclodextrins. They have been used to increase the solubility of poorly soluble actives, to protect the labile groups and control the release. This study aimed at formulating complexes of CFDwith three types of β-cyclodextrin NS obtained with different cross-linking ratio (viz. 1:2, 1:4 and 1:8 on molar basis with the cross-linker) to protect the lactone ring from hydrolysis and to prolong the release kinetics of CFD. Crystalline (F1:2, F1:4 and F1:8) and paracrystalline NS formulations were prepared. XRPD, DSC and FTIR studies confirmed the interactions of CFDwith NS. XRPD showed that the crystallinity of CFD decreased after loading. CFD was loaded as much as 21%, 37% and 13% w/w in F1:2 , F1:4 and F1:8, respectively while the paracrystalline NS formulations gave a loading of about 10% w/w or lower. The particle sizes of the loaded NS formulations were between 450 and 600 nm with low polydispersity indices. The zeta potentials were sufficiently high (-20 to -25 mV) to obtain a stable colloidal nanosuspension. The in vitro studies indicated a slow and prolonged CFD release over a period of 24 h. The NS formulations protected the lactone ring of CFD after their incubation in physiological conditions at 37°C for 24 h with a 80% w/w of intact lactone ring when compared to only around 20% w/w of plain CFD

    Influence of nitric oxide on in vitro growth, survival, steroidogenesis, and apoptosis of follicle stimulating hormone stimulated buffalo (Bubalus bubalis) preantral follicles

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    Effect of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on in vitro survival, growth, steroidogenesis, and apoptosis of buffalo preantral follicles (PFs) was investigated. PFs (200~250 µm) were isolated by micro-dissection and cultured in 0 (control), 10-3, 10-5, 10-7, and 10-9 M SNP. To examine the reversible effect of SNP, PFs were cultured with 10-5 M SNP + 1 mM Nω-nitro-L-arginine methyl ester (L-NAME) or 1.0 µg hemoglobin (Hb). The results showed that greater concentrations of SNP (10-3, 10-5, 10-7 M) inhibited (p < 0.05) FSH-induced survival, growth, antrum formation, estradiol production, and oocyte apoptosis in a dose-dependent manner. However, a lower dose of SNP (10-9 M) significantly stimulated (p < 0.05) the survival, growth, antrum formation, follicular oocyte maturation, and stimulated progesterone secretion compared to the control. A combination of SNP + L-NAME promoted the inhibitor effect of SNP while a SNP + Hb combination reversed this effect. Nitrate and nitrite concentrations in the culture medium increased (p < 0.05) in a dose-dependent manner according to SNP concentration in the culture medium. At higher concentrations, SNP had a cytotoxic effect leading to follicular oocyte apoptosis whereas lower concentrations have stimulatory effects. In conclusion, NO exerts a dual effect on its development of buffalo PFs depending on the concentration in the culture medium

    Trends in future health financing and coverage: future health spending and universal health coverage in 188 countries, 2016–40

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    Background: Achieving universal health coverage (UHC) requires health financing systems that provide prepaid pooled resources for key health services without placing undue financial stress on households. Understanding current and future trajectories of health financing is vital for progress towards UHC. We used historical health financing data for 188 countries from 1995 to 2015 to estimate future scenarios of health spending and pooled health spending through to 2040. Methods: We extracted historical data on gross domestic product (GDP) and health spending for 188 countries from 1995 to 2015, and projected annual GDP, development assistance for health, and government, out-of-pocket, and prepaid private health spending from 2015 through to 2040 as a reference scenario. These estimates were generated using an ensemble of models that varied key demographic and socioeconomic determinants. We generated better and worse alternative future scenarios based on the global distribution of historic health spending growth rates. Last, we used stochastic frontier analysis to investigate the association between pooled health resources and UHC index, a measure of a country's UHC service coverage. Finally, we estimated future UHC performance and the number of people covered under the three future scenarios. Findings: In the reference scenario, global health spending was projected to increase from US10trillion(9510 trillion (95% uncertainty interval 10 trillion to 10 trillion) in 2015 to 20 trillion (18 trillion to 22 trillion) in 2040. Per capita health spending was projected to increase fastest in upper-middle-income countries, at 4·2% (3·4–5·1) per year, followed by lower-middle-income countries (4·0%, 3·6–4·5) and low-income countries (2·2%, 1·7–2·8). Despite global growth, per capita health spending was projected to range from only 40(24–65)to40 (24–65) to 413 (263–668) in 2040 in low-income countries, and from 140(90–200)to140 (90–200) to 1699 (711–3423) in lower-middle-income countries. Globally, the share of health spending covered by pooled resources would range widely, from 19·8% (10·3–38·6) in Nigeria to 97·9% (96·4–98·5) in Seychelles. Historical performance on the UHC index was significantly associated with pooled resources per capita. Across the alternative scenarios, we estimate UHC reaching between 5·1 billion (4·9 billion to 5·3 billion) and 5·6 billion (5·3 billion to 5·8 billion) lives in 2030. Interpretation: We chart future scenarios for health spending and its relationship with UHC. Ensuring that all countries have sustainable pooled health resources is crucial to the achievement of UHC. Funding: The Bill & Melinda Gates Foundation

    Alcohol use and burden for 195 countries and territories, 1990-2016 : a systematic analysis for the Global Burden of Disease Study 2016

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    Background Alcohol use is a leading risk factor for death and disability, but its overall association with health remains complex given the possible protective effects of moderate alcohol consumption on some conditions. With our comprehensive approach to health accounting within the Global Burden of Diseases, Injuries, and Risk Factors Study 2016, we generated improved estimates of alcohol use and alcohol-attributable deaths and disability-adjusted life-years (DALYs) for 195 locations from 1990 to 2016, for both sexes and for 5-year age groups between the ages of 15 years and 95 years and older. Methods Using 694 data sources of individual and population-level alcohol consumption, along with 592 prospective and retrospective studies on the risk of alcohol use, we produced estimates of the prevalence of current drinking, abstention, the distribution of alcohol consumption among current drinkers in standard drinks daily (defined as 10 g of pure ethyl alcohol), and alcohol-attributable deaths and DALYs. We made several methodological improvements compared with previous estimates: first, we adjusted alcohol sales estimates to take into account tourist and unrecorded consumption; second, we did a new meta-analysis of relative risks for 23 health outcomes associated with alcohol use; and third, we developed a new method to quantify the level of alcohol consumption that minimises the overall risk to individual health. Findings Globally, alcohol use was the seventh leading risk factor for both deaths and DALYs in 2016, accounting for 2.2% (95% uncertainty interval [UI] 1.5-3.0) of age-standardised female deaths and 6.8% (5.8-8.0) of age-standardised male deaths. Among the population aged 15-49 years, alcohol use was the leading risk factor globally in 2016, with 3.8% (95% UI 3.2-4-3) of female deaths and 12.2% (10.8-13-6) of male deaths attributable to alcohol use. For the population aged 15-49 years, female attributable DALYs were 2.3% (95% UI 2.0-2.6) and male attributable DALYs were 8.9% (7.8-9.9). The three leading causes of attributable deaths in this age group were tuberculosis (1.4% [95% UI 1. 0-1. 7] of total deaths), road injuries (1.2% [0.7-1.9]), and self-harm (1.1% [0.6-1.5]). For populations aged 50 years and older, cancers accounted for a large proportion of total alcohol-attributable deaths in 2016, constituting 27.1% (95% UI 21.2-33.3) of total alcohol-attributable female deaths and 18.9% (15.3-22.6) of male deaths. The level of alcohol consumption that minimised harm across health outcomes was zero (95% UI 0.0-0.8) standard drinks per week. Interpretation Alcohol use is a leading risk factor for global disease burden and causes substantial health loss. We found that the risk of all-cause mortality, and of cancers specifically, rises with increasing levels of consumption, and the level of consumption that minimises health loss is zero. These results suggest that alcohol control policies might need to be revised worldwide, refocusing on efforts to lower overall population-level consumption.Peer reviewe
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