640 research outputs found
PERBEDAAN HASIL BELAJAR SISWA YANG DIAJARKAN DENGAN MODEL PEMBELAJARAN KOOPERATIF TIPE STUDENT FACILITATOR AND EXPLAINING DAN MODEL PEMBELAJARAN KONVENSIONAL PADA MATERI STATISTIKA DI KELAS XI SMA NEGERI 1 TNS
Penelitian ini bertujuan untuk mengetahui ada tidaknya perbedaan hasil belajar siswa kelas XI SMA Negeri 1 TNS yang diajarkan menggunakan model pembelajaran kooperatif tipe Student Facilitator and Explaining (SFE) dan model pembelajaran konvensional pada materi statistika. Tipe penelitian yang digunakan adalah penelitian eksperimen dengan desain penelitian Post-Test Only Control Group Design. Populasi dalam penelitian ini adalah 90 siswa dan sampel dalam penelitian ini adalah 44 siswa, dipilih menggunakan purposive sampling (sampel Bertujuan). Instrumen yang digunakan dalam penelitian ini berupa soal tes yang terdiri dari 6 soal uraian untuk tes akhir. Analisis yang digunakan adalah analisis statistik uji t dan hasil penelitian menunjukan ada perbedaan hasil belajar siswa kelas eksperimen dan kelas kontrol yang diajarkan dengan model pembelajaran kooperatif tipe Student Facilitator and Explaining (SFE) dan model pembelajaran konvensional pada materi statistika. Hal ini dibuktikan dengan hasil perhitungan yang diperoleh yakni, nilai t_hitung = 2,6491 lebih besar dari nilai t_tabel = 1,682 dan nilai Sig. (2-tailed) lebih kecil dari nilai α = 0,05 yakni 0,00
Surface integrity of additive manufacturing parts: a comparison between optical topography measuring techniques
Additive Manufacturing (AM) presents significant industry-specific advantages allowing the creation of complex geometries and internal features that cannot be produced using conventional manufacturing processes. However, a current limitation of AM is the degraded dimensional control and surface integrity of specific surfaces. The parts are constructed through layer-by-layer approach, each layer presenting a characteristic ‘fingerprint’. The functional performance of the final part is influenced by the morphology of the outer surface as well as by the surface quality introduced at intermediate layers. Surface texture metrology therefore can play an enabling role in AM-related manufacture and research. The use of optical topography measurement instrumentation allows for a high level of detail in the acquisition of topographic information. Some of the most commonly used optical measuring instruments are Vertical Scanning Interferometry (CSI), Imaging Confocal Microscopy (CONF), and Focus Variation (FV), each one has benefits and drawbacks in terms of acquisition time and measurement resolution.
AM surfaces overall present complex topographical features, requiring the acquisition of large surface areas and large z-scans which considerably increases the acquisition time. Speed is a key factor in industrial practice, and time optimization is required for quality control and surface analysis before down-stream processes. This paper reports on the measurement and characterisation of the surface texture of metal powder bed fusion AM parts. All measurements were performed in the same SENSOFAR S-NEOX instrument using the commonly used optical technologies (CSI, CONF, and FV) and the latest step in confocal measurement technology called Continuous Confocal (C-CONF). The resolution and acquisition time of each technique is analysed in order to check the suitability of each method to characterize and describe the AM surface microstructures in a time-efficient way
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Sentinel Case of Candida auris in the Western United States Following Prolonged Occult Colonization in a Returned Traveler from India.
Candida auris is an emerging multidrug-resistant yeast with high mortality. We report the sentinel C. auris case on the United States West Coast in a patient who relocated from India. We identified close phylogenetic relatedness to the South Asia clade and ERG11 Y132F and FKS1 S639Y mutations potentially explaining antifungal resistance
Altered bone metabolism in children infected with human immunodeficiency virus.
AIM: Data on bone homoeostasis of children infected with human immunodeficiency virus (HIV), at the time of the gain in bone mass, are very rare. To determine possible alterations in bone metabolism, 13 prepubertal vertically HIV-infected children were studied. METHODS: Viral load, CD4 count, interleukin-6 (IL-6), growth hormone, insulin-like growth factor-I (IGF-I), IGF binding protein-3 (IGFBP-3), acid-labile subunit (ALS), IGFBP-3 proteolysis, osteocalcin in blood and N-terminal telopeptide of type I collagen in urine were determined. Lumbar spine bone mineral density was examined by dual-energy X-ray absorptiometry. RESULTS: Low osteocalcin levels were found in all patients. Low IGF-I was found in only six children, who had low CD4 count and high IL-6 levels, with normal levels of IGFBP-3 and ALS, absent IGFBP-3 proteolysis and decreased bone mineral density, irrespective of viral load or growth. CONCLUSION: Low serum osteocalcin levels appear to be an initial warning sign of possible altered bone metabolism in HIV-infected children. However, only when the immune system becomes more seriously compromised is bone loss measurable by bone densitometry
Enhancing non-profit engagement: the extended model of webpage engagement and adoption for strategic management
This paper examines the study of Non-Profit Organization’s (NPOs’) webpages through the Strategic Online Communication Approach (SOCA) context to underpin public engagement. Although it can be argued that social networking sites such as Facebook or Twitter have a significant role in interactive online engagement, it is often webpages that have the critical role in creating engagement in the initial (and arguably most important) stage of opening dialog. In the SOCA context NPOs’ webpages need to be strategically planned and aligned with the NPOs goals and targeted to various stakeholders such as the general public, volunteers and donors. In general terms, this research resulted in a sequential model called EMEA (Extended Model of Webpages Engagement and Adoption) with three levels (information, interaction, and action). The EMEA model shows the efficiency and maturity of the webpages, indicating the level of engagement that should be possible, to therefore improve relationships with the public and obtain better results. Results show that the more ‘ways to help’ an NPO presents on its webpage, the greater the level of potential engagement (as different options to collaborate, convey trustworthy information, and control content are evident). Finally, this research showed that the greater engagement achieved by NPOs, the better the likely results and therefore the effective application of EMEA can explain and even predict success for NPOs. This paper only addresses web pages, and therefore further research is needed to clarify the role of Social Networking Sites (SNS) for high interactivity. Secondly, although EMEA is able to explain and even predict the levels of engagement, it is not evident that it necessarily occurs. Finally, although EMEA is applied correctly, it does not guarantee that NPOs are managing communication in the context of SOCA, since a multi-channel online strategy is required
Calcium Supplementation Increases Bone Mass in GH-Deficient Prepubertal Children during GH Replacement
Bone development during GH and GnRH analog treatment
Estrogens, GH and IGFs are essential in the development and growth of the skeleton and for the main-tenance of bone mass and density. Treatment of precocious puberty with GnRH analogs (GnRHa), by reducing sex steroid levels, leads to a situation of hypoestrogenism that may theoretically have a det-rimental effect on bone mass during pubertal development. A reduction in bone mineral density (BMD) during GnRHa treatment has been demonstrated, but GnRHa treatment in patients with cen-tral precocious puberty (CPP) does not seem to impair the achievement of normal peak bone mass (PBM) at final height. However, calcium supplementation is effective in improving bone densitometric levels and may promote better PBM achievement. In children and adolescents with GH deficiency (GHD), BMD assessed by dual-energy X-ray absorptiometry (DEXA) and bone turnover are signifi-cantly reduced, but they are stimulated by GH treatment. GH treatment leads to improved bone den-sity, function of the dose and duration of treatment, and patients may require prolonged GH treatment beyond the time of growth to improve PBM. After the discontinuation of GH therapy, the more active population had higher bone mineral content (BMC) levels than patients with low physical activity. In our experience, the therapeutic association of GH and calcium also represents a valuable tool in pur-suing a proper BMC in GHD patients. We concluded that nonhormonal factors, such as physical activity and nutritional factors, are important in determining bone metabolism and bone mass. European Journal of Endocrinology 151 S47–S5
The de Rham homotopy theory and differential graded category
This paper is a generalization of arXiv:0810.0808. We develop the de Rham
homotopy theory of not necessarily nilpotent spaces, using closed dg-categories
and equivariant dg-algebras. We see these two algebraic objects correspond in a
certain way. We prove an equivalence between the homotopy category of schematic
homotopy types and a homotopy category of closed dg-categories. We give a
description of homotopy invariants of spaces in terms of minimal models. The
minimal model in this context behaves much like the Sullivan's minimal model.
We also provide some examples. We prove an equivalence between fiberwise
rationalizations and closed dg-categories with subsidiary data.Comment: 47 pages. final version. The final publication is available at
http://www.springerlink.co
Profesionalizarse, emprender y aliarse para que la empresa familiar continúe
La continuidad de la empresa familiar es uno de los temas más estudiados. Los factores más utilizados en su estudio son la sucesión y la confusión entre el patrimonio empresarial y familiar. Sin embargo, en este trabajo vamos a analizar la continuidad de la empresa familiar y la influencia que sobre ella tienen algunas variables poco estudiadas; en concreto analizaremos la influencia que sobre ella tienen la realización de estrategias de alianzas y cooperación, la gestión profesional de la empresa familiar y el espíritu emprendedor de la empresa. La metodología utilizada para analizar estas relaciones está basada en un proceso de ecuaciones estructurales, concretamente el enfoque Partial Least Squares (PLS). Los resultados son, en la mayoría de las relaciones empleadas, los esperados según la literatura
Epidemic history of hepatitis C virus genotypes and subtypes in Portugal
Any successful strategy to prevent and control HCV infection requires an understanding of the epidemic behaviour among the different genotypes. Here, we performed the first characterization of the epidemic history and transmission dynamics of HCV subtypes in Portugal. Direct sequencing of NS5B was performed on 230 direct-acting antiviral drugs (DAA)-treatment naïve patients in Lisbon. Phylogenetic analysis was used for subtyping and transmission cluster identification. Bayesian methods were used to reconstruct the epidemic history of HCV subtypes. Sequences were analysed for resistance-associated substitutions (RAS). The majority of strains were HCV-GT1 (62.6%), GT3 (18.3%, all subtype 3a) and GT4 (16.1%). Among GT1, the most frequent were subtypes 1a (75.5%) and 1b (24.5%). Polyphyletic patterns were found in all but 12 lineages suggesting multiple introductions of the different subtypes in this population. Five distinct epidemics were identified. The first significant HCV epidemic in Portugal occurred between 1930s and 1960s, was caused almost exclusively by GT1b and was likely associated with blood transfusions. Rapid expansion of GT3a occurred in the 1960s and GT1a in the 1980s, associated with intravenous drug use. The most recent epidemics were caused by GT4a and GT4d and seem to be associated with the resurgence of opioid use. The C316N substitution was found in 31.4% of GT1b-patients. Close surveillance of patients bearing this mutation and undergoing dasabuvir-based regimens will be important to determine its impact on treatment outcome.publishersversionpublishe
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