Discrete modelling of heat transfer

The research involves the development of a discrete lattice approach for modelling heat transfer, which can be an attractive alternative to other numerical approaches, such as the nite element method. In this work, the spatial arrangement of the lattice elements is determined by the Delaunay triangulation and the Voronoi tessellation. The objective of the present work is to investigate in more detail this type of lattice model for heat transfer. In the lattice models studied here the domain to be analysed is discretised by a network of discrete lattice elements. The spatial arrangement of these elements is determined by connecting nodes placed within the domain. There are two methods to determine the connections between the nodes in the domain. In the rst one, the connections are dened as the edges of the Delaunay triangulation. In the second method, the nodes are dened by the edges of Voronoi cells, based on a Voronoi tessellation of the domain. These connections dene the arrangement of the pipe elements, which are used to perform the heat transfer analysis. The cross-sections of the pipe elements for the two approaches are chosen in several dierent ways to be consistent with the discretisation approach. It was shown that with this approach, analytical solutions could be represented accu- rately. Several stationary and non-stationary heat transfer problems were analysed. The performance of the two approaches was evaluated by comparing the numerical results with analytical solutions. Both temperature and ux distributions were studied.

Sejarah Sistem Pendidikan di Indonesia dari Masa ke Masa: Sebuah Studi Literatur

Artikel ini membahas tentang sejarah sistem Pendidikan dari masa ke masa. Dimana terdiri dari masa hindu budha, islam, Portugis, orde lama, orde baru dan reformasi. Tujuan dari penulisan artikel ini adalah untuk menguraikan bagaimana sistem Pendidikan pada setiap masa di Indonesia. Artikel ini ditulis dengan metode studi literatur. Studi literatur adalah metode yang dilakukan dengan mencari terlebih dahulu sumber-sumber bacaan yang relevan untuk kemudian dikumpulkan informasinya dan disusun dengan menggunakan pernyataan deskriptif. Seperti yang kita tahu bahwa pendidikan merupakan hal yang penting dalam kehidupan manusia karena Pendidikan dapat digunakan sebagai penunjang untuk hidup lebih baik di masa mendatang. Sebenarnya pendidikan telah dikenal sejak dahulu kala. Namun, Pendidikan pada zaman dahulu masih sangat buruk dan pelaksanaannya pun tidak merata. Pendidikan hanya diperuntukkan bagi kaum bangsawan dan orang berdarah biru sehingga rakyat biasa dianggap tidak layak untuk mendapat Pendidikan. Namun seiring berkembangnya zaman, pendidikan mulai berkembang dan menjadi lebih baik mengikuti zamannya. Perkembangan tersebut juga diikuti dengan perubahan-perubahan yang dinilai cocok dengan suatu masa. Tentu saja setiap masa memiliki ciri khas yang berbeda-beda dan memiliki beragam cerita menarik pada setiap masany

Case-control study of the association of use of health services by children with behavioural and developmental disorders with prenatal alcohol exposure

Includes bibliographical references.Background Prenatal alcohol exposure can result in a range of permanent birth defects known as Fetal Alcohol Spectrum Disorders (FASD). Fetal Alcohol Syndrome (FAS), which detrimentally affects the neurodevelopmental, physical, and social capabilities of children, is the most severe diagnosis on this scale of disorders. Research suggests that FASD rates exceed FAS in various populations. South Africaâs Western Cape region has one of the highest rates of FAS in the world. Hypothesis In populations where the prevalence of full-blown FAS is already known to be high, such as the Western Cape, other, less severe childhood developmental and behavioural disorders may be due to prenatal alcohol exposure. Objectives The aim of this research was to determine the odds of maternal alcohol use in children with behavioural and/or developmental disorders (BDD) in comparison to children free from behavioural disorders. This project also examined the average utilisation of health services by children with BDD as an arm of a larger study on the economic burden of FAS in South Africa. Methods Opportunistic sampling was employed to select parents or caretakers of 110 children aged 4 to 12 for interviews at a tertiary childrenâs public hospital in Cape Town. Health service utilization and maternal alcohol consumption habits were compared between 55 cases, children with BDD and 55 controls, children free from such disorders. Univariate analyses and logistic regression methods were used to determine these associations. Ethics The University of Cape Town Research Ethics Committee approved this study. Dr. T. Blake, Senior Medical Superintendent of Red Cross War Memorial Childrenâs Hospital granted access to Red Cross Hospital. Before each study interview was conducted, informed consent, which emphasized confidentiality of responses and the right to refuse to answer a question or withdraw from the interview, was taken from the adult respondent. We also explained to participants that they would remain anonymous and that their answers would not affect their childâs treatment in the clinics. Results BDD were significantly associated with current maternal alcohol consumption, maternal binge drinking in the last six months, and maternal alcohol use six months before pregnancy, but not significantly with reported maternal gestational drinking. The median number of visits to a clinic in the last six months was significantly higher for cases than for controls. Conclusions Childhood BDD among our study participants were not attributed to prenatal alcohol exposure. Current maternal alcohol consumption has a significant impact on BDD in children, possibly serving as a proxy for unstable home environments. The competing environmental factors that influence childhood BDD warrants further research

Corrosion fatigue of reinforced concrete

This work is concerned with the corrosion fatigue characteristics of full-scale reinforced concrete beams partially submerged in 3.5% NaCl solution or in tapwater of low dissolved salt content. The test beams were subjected to constant amplitude fatigue loading in uni-directional or reverse bending at slow cycle rate of 0.17 Hz and various load levels. The test programme had two stages: Stage I, carried out at relatively high load levels, represented a study of the fatigue-failure phenomenon but also provided guides for the more detailed study undertaken in Stage II which was devoted to low load conditions under which the main steel deterioration process was corrosion. In the latter stage, attention was focused on the monitoring of a number of electrochemical parameters including the corrosion rate. Late in the programme, electrochemical noise technique was also examined.The phenomenon of concrete crack blocking, previously reported in seawater environment, was observed in both test environments in this work. This phenomenon was closely examined and the mechanisms of the formation of deposits and its effects were described. A hypothesis was proposed for the structural behaviour of reinforced concrete beams during cyclic loading in aqueous environment. Failure normally occurred by the fracture of one of the main tensile bars due to fatigue, often followed immediately by yield of the remaining bar and beams collapse. Fracture surfaces were examined under SEM.Corrosion rate measurements involved formidable difficulties which had to be overcome to obtain accurate measurements. For instance, the current interruption technique for the estimation of the IR-drop was developed and established as the most appropriate method for concrete beams with complex reinforcement configuration. Extensive polarisation measurements indicated clear effect of the test condition on the technical variables involved in various measuring techniques (viz potentiodynamic and potentiostatic techniques). Based on these observations a criterion has been proposed to determine the appropriate variables necessary for the accurate determination of the polarisation resistance Rp.The work has demonstrated that the corrosion behaviour of reinforced concrete sustaining dynamic loading is extremely complex, and short term indications could not be used safely for long term predictions. Based on corrosion rate measurements and the actual corrosion pattern observed upon completion of the tests, a concept of a change in corrosion mechanism from a microcell process of relatively low corrosion rates to a macrocell process at much accelerated high rates is introduced. The prevailing mechanism depends on time of exposure, load level and reinforcement details. Results from long running fatigue tests in seawater from concurrent research were incorporated which also support this concept

High fat diet attenuates the anticontractile activity of aortic PVAT via a mechanism involving AMPK and reduced adiponectin secretion

Background and aim: Perivascular adipose tissue (PVAT) positively regulates vascular function through production of factors such as adiponectin but this effect is attenuated in obesity. The enzyme AMP-activated protein kinase (AMPK) is present in PVAT and is implicated in mediating the vascular effects of adiponectin. In this study, we investigated the effect of an obesogenic high fat diet (HFD) on aortic PVAT and whether any changes involved AMPK. Methods: Wild type Sv129 (WT) and AMPKα1 knockout (KO) mice aged 8 weeks were fed normal diet (ND) or HFD (42% kcal fat) for 12 weeks. Adiponectin production by PVAT was assessed by ELISA and AMPK expression studied using immunoblotting. Macrophages in PVAT were identified using immunohistochemistry and markers of M1 and M2 macrophage subtypes evaluated using real time-qPCR. Vascular responses were measured in endothelium-denuded aortic rings with or without attached PVAT. Carotid wire injury was performed and PVAT inflammation studied 7 days later. Key results: Aortic PVAT from KO and WT mice was morphologically indistinct but KO PVAT had more infiltrating macrophages. HFD caused an increased infiltration of macrophages in WT mice with increased expression of the M1 macrophage markers Nos2 and Il1b and the M2 marker Chil3. In WT mice, HFD reduced the anticontractile effect of PVAT as well as reducing adiponectin secretion and AMPK phosphorylation. PVAT from KO mice on ND had significantly reduced adiponectin secretion and no anticontractile effect and feeding HFD did not alter this. Wire injury induced macrophage infiltration of PVAT but did not cause further infiltration in KO mice. Conclusions: High-fat diet causes an inflammatory infiltrate, reduced AMPK phosphorylation and attenuates the anticontractile effect of murine aortic PVAT. Mice lacking AMPKα1 phenocopy many of the changes in wild-type aortic PVAT after HFD, suggesting that AMPK may protect the vessel against deleterious changes in response to HFD

Childhood behavioural and developmental disorders - association with maternal alcohol consumption in Cape Town, South Africa

Current maternal alcohol consumption, especially binge drinking, is strongly associated with childhood behavioural and/or developmental disorders (BDDs) in a population attending tertiary hospital ambulatory services. BDDs were also associated with maternal alcohol use 6 months before pregnancy. An association with BDDs could not be conclusively demonstrated for drinking during pregnancy, but this may have been influenced by under-reporting and reduced study power due to misclassification of exposure. We cannot rule out the a priori suspicion that some mild BDDs in children in the Western Cape could be undiagnosed fetal alcohol spectrum disorder. Nonetheless, the study highlighted the important impact of current maternal alcohol use on behaviour and development of children. Future research on the impact of maternal alcohol use on childhood development should include examination of environmental and social factors contributing to this increased risk. Upstream interventions aimed at reducing alcohol-related harms may also contribute to reducing the burden of BDDs

Pengembangan las berbasis open-ended problem menggunakan soal PISA materi penyebaran data

Penelitian ini bertujuan untuk menghasilkan Lembar Aktivitas Siswa (LAS) berbasis open-ended problem yang valid serta untuk mengetahui efeknya terhadap hasil pembelajaran peserta didik pada materi ukuran penyebaran data kelompok. Penelitian ini menggunakan metode penelitian Research and Development (R&D) atau bisa juga disebut dengan metode Pengembangan. Subjek penelitiannnya adalah peserta didik kelas 11 SMA N 2 Rejang Lebong, sebanyak 3 orang dalam small group dan 1 orang siswi SMA N 1 Talang Kelapa dalam one to one. Menggunakan teknik pengambilan data walkthrough, wawancara, dokumentasi, dan tes soal evaluasi. Hasil penelitian yang diharapkan yaitu: (1) Penelitian ini menghasilkan LAS berbasis open-ended problem pada materi ukuran penyebaran data kelompok. (2) LAS yang telah dikembangkan diharapkan memiliki efek dalam pemahaman belajar peserta didik

Use of routine health information systems to monitor disruptions of coverage of maternal, newborn, and child health services during COVID-19: A scoping review.

BACKGROUND: The COVID-19 pandemic is a unique global health challenge which disrupted essential health services (EHS). Most early data related to EHS during the COVID-19 pandemic came from country and regional "pulse" surveys conducted by the World Health Organization (WHO) and United Nations Children's Fund (UNICEEF), which relied on respondent perceptions and not necessarily routine health information system (RHIS) data. By conducting a scoping review, we aimed to describe the use of RHIS data for monitoring changes in EHS coverage for maternal, newborn, and child health (MNCH) during the COVID-19 pandemic. METHODS: We performed a scoping review using Sample, Phenomenon of Interest, Design, Evaluation, Research type (SPIDER) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Scoping Review (PRISMA-SCR) guidelines. We included descriptive or analytic reports on the availability and use of RHIS data published in peer-reviewed, pre-publication, or gray literature on MNCH essential health services coverage during the COVID-19 pandemic. The following databases were searched for studies published between January 2020 and May 2022: PubMed/MEDLINE, Google Scholar, Google, MedRXiv (pre-publication), Embase, CINAHL, Cochrane, Campbell, and OpenGrey. A single reviewer screened the titles, abstracts, and full texts of the retrieved publications, while a second reviewer screened 20% of the total sample. Publications were tabulated by WHO Region, World Bank income group, country, data sources, study topic, and period. We used content analysis to qualitatively describe the trends and use of data for policy or programming in the studies. RESULTS: We included 264 publications after the full-text review. The publications came from 81 countries, covering all WHO regions and World Bank income groups. The most common data sources were hospital information systems (27%) and primary health care management information systems (26%). Most studies examined data trends before COVID-19 compared to periods during COVID-19. Most publications reported a decrease in MNCH services (45%). Reports with follow-up beyond August 2020 (first six months of pandemic) were significantly more likely to report recovery of service coverage (8% vs 30%, P < 0.001). Low- and middle-income countries reported significantly higher morbidity and/or mortality in COVID-19 periods than high-income countries (54% vs 30%, P < 0.001). Less than 10% of reports described RHIS data quality specifically during the COVID-19 period and only 22% reported program mitigation strategies to address reductions noted from routine data. CONCLUSION: Results suggest awareness and usefulness of RHIS to monitor MNCH service disruptions during the COVID-19 pandemic. However, with only 22% of reports including descriptions of policy or program adaptations, use of RHIS data to monitor MNCH service disruptions was not necessarily followed by data-informed policies or program adaptations. RHIS data on MNCH services should be strengthened to enable its use by program managers and policymakers to respond to direct and indirect effects of future public health emergencies. REGISTRATION: Open Science Framework (available at: https://osf.io/usqp3/?view_only=94731785fcba4377adfa1bdf5754998d)

Deletion of AMPKα1 attenuates the anticontractile effect of perivascular adipose tissue (PVAT) and reduces adiponectin release

Background and Purpose: Perivascular adipose tissue (PVAT) surrounds most blood vessels and secretes numerous active substances, including adiponectin, which produce a net anticontractile effect in healthy individuals. AMPK is a key mediator of cellular energy balance and may mediate the vascular effects of adiponectin. In this study, we investigated the role of AMPK within PVAT in mediating the anticontractile effect of PVAT. Experimental Approach: Endothelium-denuded aortic rings from wild-type (WT; Sv129) and α1AMPK knockout (KO) mice were mounted on a wire myograph. Dose–response curves to the AMPK-independent vasodilator cromakalim were studied in vessels with and without PVAT, and effect of pre-incubation with conditioned media and adiponectin on relaxation was also studied. The effect of AMPKα1 KO on the secretory profile of PVAT was assessed by elisa. Key Results: Thoracic aortic PVAT from KO mice was morphologically indistinct from that of WT and primarily composed of brown adipose tissue. PVAT augmented relaxation to cromakalim in WT but not KO aortic rings. Addition of WT PVAT augmented relaxation in KO aortic rings but KO PVAT had no effect in WT rings. PVAT from KO mice secreted significantly less adiponectin and addition of adiponectin to either KO or WT aortic rings without PVAT augmented relaxation to cromakalim. An adiponectin blocking peptide significantly attenuated relaxation in WT rings with PVAT but not in KO rings. Conclusions and Implications: AMPKα1 has a critical role in maintaining the anticontractile actions of PVAT; an effect independent of the endothelium but likely mediated through altered adiponectin secretion or sensitivity

The UN Commission on Life Saving Commodities 3 years on: global progress update and results of a multicountry assessment

Background In September, 2012, the UN Commission on Life Saving Commodities (UNCoLSC) outlined a plan to expand availability and access to 13 life saving commodities. We profi le global and country progress against these recommendations between 2012 and 2015. Methods For 12 countries in sub-Saharan Africa that were off -track to achieve the Millennium Development Goals for maternal and child survival, we reviewed key documents and reference data, and conducted interviews with ministry staff and partners to assess the status of the UNCoLSC recommendations. The RMNCH fund provided short-term catalytic fi nancing to support country plans to advance the commodity agenda, with activities coded by UNCoLSC recommendation. Our network of technical resource teams identifi ed, addressed, and monitored progress against cross-cutting commodity-related challenges that needed coordinated global action. Findings In 2014 and 2015, child and maternal health commodities had fewer bottlenecks than reproductive and neonatal commodities. Common bottlenecks included regulatory challenges (ten of 12 countries); poor quality assurance (11 of 12 countries); insuffi cient staff training (more than half of facilities on average); and weak supply chains systems (11 of 12 countries), with stock-outs of priority commodities in about 40% of facilities on average. The RMNCH fund committed US$175·7 million to 19 countries to support strategies addressing crucial gaps.$68·2 million (39·0%) of the funds supported systems-strengthening interventions with the remainder split across reproductive, maternal, newborn, and child health. Health worker training ($88·6 million, 50·4 ($53·3 million, 30·0%), and demand generation ($21·1 million, 12·0%) were the major topics of focus. All priority commodities are now listed in the WHO Essential Medicines List; appropriate price reductions were secured; quality manufacturing was improved; a fast-track registration mechanism for prequalifi ed products was established; and methods were developed for advocacy, quantifi cation, demand generation, supply chain, and provider training. Slower progress was evident around regulatory harmonisation and quality assurance. Interpretation Much work is needed to achieve full implementation of the UNCoLSC recommendations. Coordinated eff orts to secure price reductions beyond the 13 commodities and improve regulatory effi ciency, quality, and supply chains are still needed alongside broader dissemination of work products