171 research outputs found

    Hyperfine collisional excitation of ammonia by molecular hydrogen

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    Ammonia is one of the most widely observed molecules in space, and many observations are able to resolve the hyperfine structure due to the electric quadrupole moment of the nitrogen nucleus. The observed spectra often display anomalies in the satellite components of the lines, which indicate substantial deviations from the local thermodynamic equilibrium. The interpretation of the spectra thus requires the knowledge of the rate coefficients for the hyperfine excitation of NH3_3 induced by collisions with H2_2 molecules, the dominant collider in the cold interstellar medium. In this paper we present the first such calculations using a recoupling approach. The rate coefficients are obtained for all hyperfine levels within rotation-inversion levels up to j=4j=4 and temperatures up to 100 K by means of quantum scattering close-coupling calculations on an accurate, five-dimensional, potential energy surface. We show that the rate coefficients depart significantly from those obtained with the statistical approach and that they do not conform to any simple propensity rules. Finally, we perform radiative transfer calculations to illustrate the impact of our new rate coefficients by modelling the hyperfine line intensities of the inversion transition in ground state para-NH3_3 (jk=11j_k=1_1) and of the rotational transition 10001_0\rightarrow 0_0 in ortho-NH3_3

    Role of Nonbehavioral Factors in Adjusting Long Bone Diaphyseal Structure in Free-ranging Pan troglodytes

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    Limb bones deform during locomotion and can resist the deformations by adjusting their shapes. For example, a tubular-shaped diaphysis best resists variably-oriented deformations. As behavioral profiles change during adulthood, patterns of bone deformation may exhibit age trends. Habitat characteristics, e.g., annual rainfall, tree density, and elevation changes, may influence bone deformations by eliciting individual components of behavioral repertoires and suppressing others, or by influencing movements during particular components. Habituated chimpanzee communities provide a unique opportunity to examine these factors because of the availability of morphological data and behavioral observations from known-age individuals inhabiting natural habitats. We evaluated adult femora and humeri of 18 female and 10 male free-ranging chimpanzees (Pan troglodytes) from communities in Gombe (Tanzania), Mahale Mountains (Tanzania), and Taï Forest (Côte d’Ivoire) National Parks. We compare cross sections at several locations (35%, 50%, 65% diaphyseal lengths). Community comparisons highlight different diaphyseal shapes of Taï females relative to Mahale and Gombe females, particularly in humeral diaphyses. Age trends in diaphyseal shapes are consistent with reduced activity levels in general, not only reduced arboreal activity. Age-related bone loss is apparent among community females, but is less striking among males. Community trends in diaphyseal shape are qualitatively consistent with ranked annual rainfall at localities, tree density, and elevation change or ruggedness of terrain. Habitat characteristics may contribute to variation in diaphyseal shape among chimpanzee communities, much like among modern human groups, but verification awaits further rigorous experimental and comparative analyses

    Machine-learning-aided prediction of brain metastases development in non-small-cell lung cancers

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    Purpose Non–small-cell lung cancer (NSCLC) shows a high incidence of brain metastases (BM). Early detection is crucial to improve clinical prospects. We trained and validated classifier models to identify patients with a high risk of developing BM, as they could potentially benefit from surveillance brain MRI. Methods Consecutive patients with an initial diagnosis of NSCLC from January 2011 to April 2019 and an in-house chest-CT scan (staging) were retrospectively recruited at a German lung cancer center. Brain imaging was performed at initial diagnosis and in case of neurological symptoms (follow-up). Subjects lost to follow-up or still alive without BM at the data cut-off point (12/2020) were excluded. Covariates included clinical and/or 3D-radiomics-features of the primary tumor from staging chest-CT. Four machine learning models for prediction (80/20 training) were compared. Gini Importance and SHAP were used as measures of importance; sensitivity, specificity, area under the precision-recall curve, and Matthew's Correlation Coefficient as evaluation metrics. Results Three hundred and ninety-five patients compromised the clinical cohort. Predictive models based on clinical features offered the best performance (tuned to maximize recall: sensitivity∼70%, specificity∼60%). Radiomics features failed to provide sufficient information, likely due to the heterogeneity of imaging data. Adenocarcinoma histology, lymph node invasion, and histological tumor grade were positively correlated with the prediction of BM, age, and squamous cell carcinoma histology were negatively correlated. A subgroup discovery analysis identified 2 candidate patient subpopulations appearing to present a higher risk of BM (female patients + adenocarcinoma histology, adenocarcinoma patients + no other distant metastases). Conclusion Analysis of the importance of input features suggests that the models are learning the relevant relationships between clinical features/development of BM. A higher number of samples is to be prioritized to improve performance. Employed prospectively at initial diagnosis, such models can help select high-risk subgroups for surveillance brain MRI

    Molecular-rotation-induced splitting of the binary ridge in the velocity map of sub-eV H+ ions ejected from H2 molecules by ion impact

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    In studies of ion-induced molecular fragmentation, the challenging measurement of the velocity distribution of fragments emitted below 1-eV kinetic energy is rarely achieved, although most fragments have an energy below this value. Here, we study H+ fragment emission in collisions of 10-keV O+ ions with H2 molecules using a field-free time-of-flight technique developed specifically to detect sub-eV fragments. We find that, in the velocity map, the binary ridge due to direct H+ knockout is split into two parts arising from the rotational motion of the H2 molecule, and that this split scales with rotational velocity. The velocity distribution of the nuclei in the original molecule is determined and the thermally populated J = 1 rotational level is found to be the dominant contributor, although asymmetry in the split indicates projectile-induced rotational transitions between M sub-levels. These rotation effects influence fragment emission probabilities, thus carrying important consequences for the radiation-induced hydrogen loss and H2 dissociation in the atmospheres or exospheres of planets and moons

    Radiographs Reveal Exceptional Forelimb Strength in the Sabertooth Cat, Smilodon fatalis

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    Background: The sabertooth cat, Smilodon fatalis, was an enigmatic predator without a true living analog. Their elongate canine teeth were more vulnerable to fracture than those of modern felids, making it imperative for them to immobilize prey with their forelimbs when making a kill. As a result, their need for heavily muscled forelimbs likely exceeded that of modern felids and thus should be reflected in their skeletons. Previous studies on forelimb bones of S. fatalis found them to be relatively robust but did not quantify their ability to withstand loading. Methodology/Principal Findings: Using radiographs of the sabertooth cat, Smilodon fatalis, 28 extant felid species, and the larger, extinct American lion Panthera atrox, we measured cross-sectional properties of the humerus and femur to provide the first estimates of limb bone strength in bending and torsion. We found that the humeri of Smilodon were reinforced by cortical thickening to a greater degree than those observed in any living felid, or the much larger P. atrox. The femur of Smilodon also was thickened but not beyond the normal variation found in any other felid measured. Conclusions/Significance: Based on the cross-sectional properties of its humerus, we interpret that Smilodon was a powerful predator that differed from extant felids in its greater ability to subdue prey using the forelimbs. This enhanced forelimb strength was part of an adaptive complex driven by the need to minimize the struggles of prey in order to protec

    AKSI KOMPETENSI BERSAMA DI PANTI ASUHAN MISI NUSANTARA SURAKARTA

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    Permasalahan sosial yang banyak terjadi di masyarakat adalah kaum marjinal yang terpinggirkan seperti anak terlantar, anak jalanan, pengemis, dan sebagainya. Salah satu upaya mengatasi masalah kaum marjinal yaitu dengan didirikan lembaga sosial berupa panti asuhan anak. Sejak masa pandemi, anak di Panti Asuhan Misi Nusantara Surakarta jarang mendapat layanan kesehatan dan ada keterbatasan ruang gerak anak-anak. Tujuan pengabdian masyarakat ini untuk membantu panti asuhan dalam memantau pertumbuhan dan perkembangan penghuni dan pengelola Panti Asuhan Misi Nusantara di Surakarta. Metoda pelaksanaan berupa pemeriksaan tumbuh kembang anak, Penyuluhan Hidup Bersih dan Sehat, pemeriksaan Status Gizi Anak, penyuluhan cara menyikat gigi yang benar, pemeriksaan kesehatan pengelola panti asuhan serta pelatihan penanggulangan bencana. Hasil pemeriksaan Kesehatan pada penghuni dan pengelola panti didapatkan sebagian besar (52,6%) penghuni panti berjenis kelamin laki-laki, hampir setengahnya berusia rata-rata 21-60 tahun, Sebagian besar (68,4%) tekanan darah <140/90 mmHg, Sebagian besar (73,1%) berstatus gizi normal, hampir seluruhnya (94,4%) glukosa darah <126 m/dL dan asam urat <8 mg/dL. Secara umum keadaan warga panti asuhan dalam keadaan baik Social problems that often occur in society are abandoned children, street children, beggars, disabled people, neglected elderly, poor families, families with social problems, and so on. Children and poor people should have their human rights fulfilled by the State of Indonesia. However, in reality there are many children whose needs are not met, such as parents who are unable to provide for the child's needs or the child does not have parents. One effort to overcome this is to establish social institutions in the form of orphanages. Since the pandemic, children at the Mission Nusantara Surakarta Orphanage rarely receive health services and there is limited space for children to move. The purpose of this community service is to assist the orphanage in monitoring the growth and development of residents and managers of the Mission Nusantara Orphanage in Surakarta. The implementation method is in the form of examinations on child growth and development, Counseling on Clean and Healthy Living, checking on the Nutritional Status of Children, counseling on how to brush their teeth properly, health checks for orphanage managers and training on disaster management. 6%) of the residents of the orphanage are male, almost half of them are aged 21-60 years, most (68.4%) have blood pressure < 140/90 mmHg, most (73.1%) have normal nutritional status, almost all (94.4%) blood glucose < 126 m/dL and uric acid > 8 mg/dl. Similar activities are needed to see general body health and must be monitored periodically, so that the residents of the orphanage can find out their health status, especially now that they are still in a pandemic condition Covid-1

    Developing a competency-based curriculum in HIV for nursing schools in Haiti

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    <p>Abstract</p> <p>Background</p> <p>Preparing health workers to confront the HIV/AIDS epidemic is an urgent challenge in Haiti, where the HIV prevalence rate is 2.2% and approximately 10 100 people are taking antiretroviral treatment. There is a critical shortage of doctors in Haiti, leaving nurses as the primary care providers for much of the population. Haiti's approximately 1000 nurses play a leading role in HIV/AIDS prevention, care and treatment. However, nurses do not receive sufficient training at the pre-service level to carry out this important work.</p> <p>Methods</p> <p>To address this issue, the Ministry of Health and Population collaborated with the International Training and Education Center on HIV over a period of 12 months to create a competency-based HIV/AIDS curriculum to be integrated into the 4-year baccalaureate programme of the four national schools of nursing.</p> <p>Results</p> <p>Using a review of the international health and education literature on HIV/AIDS competencies and various models of curriculum development, a Haiti-based curriculum committee developed expected HIV/AIDS competencies for graduating nurses and then drafted related learning objectives. The committee then mapped these learning objectives to current courses in the nursing curriculum and created an 'HIV/AIDS Teaching Guide' for faculty on how to integrate and achieve these objectives within their current courses. The curriculum committee also created an 'HIV/AIDS Reference Manual' that detailed the relevant HIV/AIDS content that should be taught for each course.</p> <p>Conclusion</p> <p>All nursing students will now need to demonstrate competency in HIV/AIDS-related knowledge, skills and attitudes during periodic assessment with direct observation of the student performing authentic tasks. Faculty will have the responsibility of developing exercises to address the required objectives and creating assessment tools to demonstrate that their graduates have met the objectives. This activity brought different administrators, nurse leaders and faculty from four geographically dispersed nursing schools to collaborate on a shared goal using a process that could be easily replicated to integrate any new topic in a resource-constrained pre-service institution. It is hoped that this experience provided stakeholders with the experience, skills and motivation to strengthen other domains of the pre-service nursing curriculum, improve the synchronization of didactic and practical training and develop standardized, competency-based examinations for nursing licensure in Haiti.</p

    Dental Microwear and Diet of the Plio-Pleistocene Hominin Paranthropus boisei

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    The Plio-Pleistocene hominin Paranthropus boisei had enormous, flat, thickly enameled cheek teeth, a robust cranium and mandible, and inferred massive, powerful chewing muscles. This specialized morphology, which earned P. boisei the nickname “Nutcracker Man”, suggests that this hominin could have consumed very mechanically challenging foods. It has been recently argued, however, that specialized hominin morphology may indicate adaptations for the consumption of occasional fallback foods rather than preferred resources. Dental microwear offers a potential means by which to test this hypothesis in that it reflects actual use rather than genetic adaptation. High microwear surface texture complexity and anisotropy in extant primates can be associated with the consumption of exceptionally hard and tough foods respectively. Here we present the first quantitative analysis of dental microwear for P. boisei. Seven specimens examined preserved unobscured antemortem molar microwear. These all show relatively low complexity and anisotropy values. This suggests that none of the individuals consumed especially hard or tough foods in the days before they died. The apparent discrepancy between microwear and functional anatomy is consistent with the idea that P. boisei presents a hominin example of Liem's Paradox, wherein a highly derived morphology need not reflect a specialized diet

    Hard-Object Feeding in Sooty Mangabeys (Cercocebus atys) and Interpretation of Early Hominin Feeding Ecology

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    Morphology of the dentofacial complex of early hominins has figured prominently in the inference of their dietary adaptations. Recent theoretical analysis of craniofacial morphology of Australopithecus africanus proposes that skull form in this taxon represents adaptation to feeding on large, hard objects. A modern analog for this specific dietary specialization is provided by the West African sooty mangabey, Cercocebus atys. This species habitually feeds on the large, exceptionally hard nuts of Sacoglottis gabonensis, stereotypically crushing the seed casings using their premolars and molars. This type of behavior has been inferred for A. africanus based on mathematical stress analysis and aspects of dental wear and morphology. While postcanine megadontia, premolar enlargement and thick molar enamel characterize both A. africanus and C. atys, these features are not universally associated with durophagy among living anthropoids. Occlusal microwear analysis reveals complex microwear textures in C. atys unlike those observed in A. africanus, but more closely resembling textures observed in Paranthropus robustus. Since sooty mangabeys process hard objects in a manner similar to that proposed for A. africanus, yet do so without the craniofacial buttressing characteristic of this hominin, it follows that derived features of the australopith skull are sufficient but not necessary for the consumption of large, hard objects. The adaptive significance of australopith craniofacial morphology may instead be related to the toughness, rather than the hardness, of ingested foods
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