564 research outputs found

    Hybrid deposition additive manufacturing: novel volume distribution, thermo-mechanical characterization, and image analysis

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    (c) The Author/sCAUL read and publish agreement 2022The structural integrity of additive manufacturing structures is a pronounced challenge considering the voids and weak layer-to-layer adhesion. One of the potential ways is hybrid deposition manufacturing (HDM) that includes fused filament fabrication (FFF) with the conventional filling process, also known as “HDM composites". HDM is a potential technique for improving structural stability by replacing the thermoplastic void structure with a voidless epoxy. However, the literature lacks investigation of FFF/epoxy HDM-based composites regarding optimal volume distribution, effects of brittle and ductile FFF materials, and fractographic analysis. This research presents the effects of range of volume distributions (10–90%) between FFF and epoxy system for tensile, flexure, and compressive characterization. Volume distribution in tensile and flexure samples is achieved using printable wall thickness, slot width, and maximum width. For compression, the printable wall thickness, slot diameter, and external diameter are considered. Polylactic acid and acrylonitrile butadiene styrene are used to analyze the brittle and ductile FFF structures. The research reports novel application of image analysis during mechanical characterization using high-quality camera and fractographic analysis using scanning electron microscopy (SEM). The results present surprising high tensile strain (0.038 mm/mm) and compressive strength (64.5 MPa) for lower FDM-percentages (10%, 20%) that are explained using in situ image analysis, SEM, stress–strain simulations, and dynamic mechanical analysis (DMA). In this regard, the proposed work holds novelty to apply DMA for HDM. The optimal volume distributions of 70% and 80% alongside fractographic mechanisms for lower percentages (10%, 20%) can potentially contribute to structural applications and future material-based innovations for HDM.fals

    A comparison of yield potential and cultivar performance of 20 collected purslane (Portulaca oleracea L.) accessions employing seeds vs. stem cuttings

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    A glasshouse experiment was conducted in Universiti Putra Malaysia (UPM) to evaluate the regeneration and yield potential in purslane using both seeds and stem cuttings of 20 collected accessions from different locations in Western Peninsular Malaysia. Analysis results revealed significant variations (P< 0.05) for morphological traits viz., plant height, number of main branches, number of nodes, internodal distance, stem diameter, number of leaves, leaf area, number of flowers, root length, fresh and dry weight but no significant difference were observed for physiological traits viz., total chlorophyll, net photosynthesis, stomatal conductance, transpiration, water vapor deficit and for either major micro or macro minerals. Hope our research findings will eliminate the doubt of using cutting methods for purslane propagation and cultivation among producers and consumers and will promote their determination to follow purslane production in this summer at any season and anywhere. To the best of our knowledge, this is the first attempt to evaluate and to detect any significant variations arising in morphological, physiological, and especially mineral nutrition in purslane propagated through cuttings vs. through seeds

    Exploring the perceptions of Patients with Chronic Respiratory Diseases and their insights into Pulmonary Rehabilitation in Bangladesh

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    Background: Chronic respiratory diseases (CRDs) require holistic management reflecting patient preferences, appropriate pharmacotherapy, pulmonary rehabilitation, and integrated care. We aimed to understand the perceptions of people with CRDs about their condition and pulmonary rehabilitation in Bangladesh.Methods: We conducted semi-structured interviews with a maximum variation sample of people with CRD who had participated in a feasibility study of pulmonary rehabilitation in 2021/ 2022. Interviews were transcribed verbatim, analysed in Bengali using a grounded theory approach and interpreted by a multidisciplinary team.Results: We interviewed 15 participants with COPD, asthma, or post-tuberculosis. Analysis revealed three themes. 1) Understanding CRD: patients characterised their condition by the symptoms (e.g., ‘Hapani’ meaning ‘breathlessness’) rather than describing a disease entity. Some identified occupation, previous infection or family history that they believed was the cause. 2) Perceptions of pulmonary rehabilitation: Exercise was counterintuitive as it exacerbated the breathlessness symptom that defined their disease. Views varied, though many acknowledged the benefits after a few sessions. Even with home-based programmes, participants described practical barriers to finding time for the sessions and adopted strategies to overcome the challenges. 3) Implementation: Participants highlighted the need for raising awareness of CRD and the potential of pulmonary rehabilitation in the community, adapting to the local context, and establishing an accessible resourced service. Conclusion: Understanding how patients and their communities perceive their condition and the barriers (both conceptual and logistical) to acceptance is the first step to embedding this highly effective intervention into routine healthcare services in Bangladesh with potential benefits for the increasing number of people living with CRDs in LMICs.<br/

    Vermicompost induced growth and yield performance of capsicum (Capsicum annuum L.) at sustainable rooftop farming system

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    Rooftop farming is gaining rapid popularity in urban areas, especially since the beginning of the global COVID-19 pandemic. For housebound people rooftop farming is not only a way of   potentially management of their time but also the execution of creativity. For rooftop farming vermicompost (VC) can be the most sustainable media for growing high value fruits and vegetables crops. In this regard, an experiment was carried out as a rooftop farming system at Charfassion upzila in the Bhola district of Bangladesh to observe the growth and yield performance of capsicum (Capsicum annuum) grown in different combinations of vermicompost in the winter season (2020-2021). Different agronomic and yield parameters were measured at the intervals of 30, 60, and 90 days and at the final harvest of 120 days after sowing. Among the measured parameters a mixed type of performance was achieved from varied doses of vermicompost applications and inorganic fertilizer treatment. Among the measured valuable parameters; the highest fruit length (8.85 cm), fruit diameter (10.3 cm), no. of fruits (9.51 plant-1), total wt. of fresh fruits (405.32 g/plant), fresh fruits yield (11.26 t ha-1), no. of branches (30.0 plant-1), stem girth (6.3 cm), root fresh wt. (8.80 g/plant), stem fresh wt. (23.35 g/plant),  petiole fresh wt. (6.09 g/plant), total fresh biomass (65.54 g/plant), dry wt. of fruits (76.91 g/plant),  dry wt. of total fruits: biomass ratio (7.35) and benefit-cost ratio (12.40), respectively, were observed in T5 (20t VC ha-1). So, from the overall findings of this study T5 with 20t VC application ha-1 is recommended to achieve better growth and yield of capsicum through the sustainable way of rooftop and urban farming systems and to improve soil fertility status

    A network analysis to compare biomarker profiles in patients with and without diabetes mellitus in acute heart failure

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    Aims: It is unclear whether distinct pathophysiological processes are present among patients with acute heart failure (AHF), with and without diabetes. Network analysis of biomarkers may identify correlative associations that reflect different pathophysiological pathways. Methods and results: We analysed a panel of 48 circulating biomarkers measured within 24 h of admission for AHF in a subset of patients enrolled in the PROTECT trial. In patients with and without diabetes, we performed a network analysis to identify correlations between measured biomarkers. Compared with patients without diabetes (n = 1111), those with diabetes (n = 922) had a higher prevalence of ischaemic heart disease and traditional coronary risk factors. After multivariable adjustment, patients with and without diabetes had significantly different levels of biomarkers across a spectrum of pathophysiological domains, including inflammation (TNFR-1a, periostin), cardiomyocyte stretch (BNP), angiogenesis (VEGFR, angiogenin), and renal function (NGAL, KIM-1) (adjusted P-value &lt;0.05). Among patients with diabetes, network analysis revealed that periostin strongly clustered with C-reactive protein and interleukin-6. Furthermore, renal markers (creatinine and NGAL) closely associated with potassium and glucose. These findings were not seen among patients without diabetes. Conclusion: Patients with AHF and diabetes, compared with those without diabetes, have distinct biomarker profiles. Network analysis suggests that cardiac remodelling, inflammation, and fibrosis are closely associated with each other in patients with diabetes. Furthermore, potassium levels may be sensitive to changes in renal function as reflected by the strong renal–potassium–glucose correlation. These findings were not seen among patients without diabetes and may suggest distinct pathophysiological processes among AHF patients with diabetes

    Temporal and nutritional effects on the weaner pig ileal microbiota

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    BACKGROUND: The porcine gastrointestinal microbiota has been linked to both host health and performance. Most pig gut microbiota studies target faecal material, which is not representative of microbiota dynamics in other discrete gut sections. The weaning transition period in pigs is a key development stage, with gastrointestinal problems being prominent after often sudden introduction to a solid diet. A better understanding of both temporal and nutritional effects on the small intestinal microbiota is required. Here, the development of the porcine ileal microbiota under differing levels of dietary protein was observed over the immediate post-weaning period. RESULTS: Ileal digesta samples were obtained at post-mortem prior to weaning day (day − 1) for baseline measurements. The remaining pigs were introduced to either an 18% (low) or 23% (high) protein diet on weaning day (day 0) and further ileal digesta sampling was carried out at days 5, 9 and 13 post-weaning. We identified significant changes in microbiome structure (P = 0.01), a reduction in microbiome richness (P = 0.02) and changes in the abundance of specific bacterial taxa from baseline until 13 days post-weaning. The ileal microbiota became less stable after the introduction to a solid diet at weaning (P = 0.036), was highly variable between pigs and no relationship was observed between average daily weight gain and microbiota composition. The ileal microbiota was less stable in pigs fed the high protein diet (P = 0.05), with several pathogenic bacterial genera being significantly higher in abundance in this group. Samples from the low protein and high protein groups did not cluster separately by their CAZyme (carbohydrate-active enzyme) composition, but GH33 exosialidases were found to be significantly more abundant in the HP group (P = 0.006). CONCLUSIONS: The weaner pig ileal microbiota changed rapidly and was initially destabilised by the sudden introduction to feed. Nutritional composition influenced ileal microbiota development, with the high protein diet being associated with an increased abundance of significant porcine pathogens and the upregulation of GH33 exosialidases—which can influence host-microbe interactions and pathogenicity. These findings contribute to our understanding of a lesser studied gut compartment that is not only a key site of digestion, but also a target for the development of nutritional interventions to improve gut health and host growth performance during the critical weaning transition period. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s42523-021-00119-y

    Cerebral Venous Sinus Thrombosis in Children: A Multicenter Cohort From the United States

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    This study presents a large multicenter cohort of children with cerebral venous thrombosis from 5 centers in the United States and analyzes their clinical findings and risk factors. Seventy Patients were included in the study (25 neonates, 35%). The age ranged from 6 days to 12 years. Thirty-eight (55%) were younger than 6 months of age, and 28 (40%) were male. Presenting features included seizures (59%), coma (30%), headache (18%), and motor weakness (21%). Common neurological findings included decreased level of consciousness (50%), papilledema (18%), cranial nerve palsy (33%), hemiparesis (29%), and hypotonia (22%). Predisposing factors were identified in 63 (90%) Patients. These included infection (40%), perinatal complications (25%), hypercoagulable/hematological diseases (13%), and various other conditions (10%). Hemorrhagic infarcts occurred in 40% of the Patients and hydrocephalus in 10%. Transverse sinus thrombosis was more common (73%) than sagittal sinus thrombosis (35%). Three children underwent thrombolysis, 15 Patients received anticoagulation, and 49 (70%) were treated with antibiotics and hydration. Nine (13%) Patients (6 of them neonates) died. Twenty-nine Patients (41%) were normal, whereas 32 Patients (46%) had a neurological deficit at discharge. Seizures and coma at presentation were poor prognostic indicators. In conclusion, cerebral venous thrombosis predominantly affects children younger than age 6 months. Mortality is high (25%) in neonatal cerebral venous thrombosis. Only 18 (25%) Patients were treated with anticoagulation or thrombolysis

    Predictive value of apoptosis, proliferation, HER-2, and topoisomerase IIalpha for anthracycline chemotherapy in locally advanced breast cancer

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    Purpose. Laboratory evidence indicates that tumor growth depends on the balance between cell proliferation and cell death, and many anticancer agents may exert their therapeutic effect by decreasing proliferation and increasing apoptosis. Additionally, clinical observations indicate that overexpression of HER-2 or topoisomerase II alpha ( topo II alpha) may be predictors of better response to anthracyclines in breast cancer. The objective of this study was to determine if proliferation ( Ki-67), apoptosis ( TUNEL), and expression of HER-2 and topo II alpha are affected by anthracycline treatment, and if these molecular markers predict anthracycline responsiveness. Experimental design. Thirty-three women with primary breast tumors >= 3 cm received either doxorubicin ( 75 mg/ m(2)) or epirubicin ( 120 mg/ m(2)) for 4 cycles before surgery. Clinical response was evaluated after 4 cycles of treatment. Changes in molecular markers were assessed from core needle biopsy taken before treatment (D0), at 24 - 48 h (Dl) and on day 7 (D7) while on treatment, and from the surgical specimen excised on day 84 (D84) after the fourth cycle of chemotherapy. Results. The overall clinical response rate was 51% (17 of 33 patients), with a 12% complete clinical response rate ( 4 of 33 patients). There were trends for tumors with higher apoptosis and topo IIa at baseline ( D0) to be more responsive to anthracyclines, p = 0.1 and p = 0.08, respectively. Median apoptosis increased from D0 to Dl ( p = 0.06) while median Ki-67 decreased ( p = 0.07). Overall, expression of HER-2 remained stable throughout the chemotherapy administration. By Day 84, topo II alpha had significantly decreased from baseline in responders, while it increased in non-responders, p = 0.03. Conclusions. In human primary breast cancer, anthracycline treatment causes an early increase in apoptosis and a decrease in proliferation. In this pilot study, higher apoptosis and topo II alpha a levels in primary tumors were associated with greater responsiveness to anthracyclines, and topo II alpha levels declined in responsive tumors
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