1,665 research outputs found
Influential Article Review - Children and Numbers: Does Gender Play a Role?
This paper examines education. We present insights from a highly influential paper. Here are the highlights from this paper: Recent public discussions have suggested that the under-representation of women in science and mathematics careers can be traced back to intrinsic differences in aptitude. However, true gender differences are difficult to assess because sociocultural influences enter at an early point in childhood. If these claims of intrinsic differences are true, then gender differences in quantitative and mathematical abilities should emerge early in human development. We examined cross-sectional gender differences in mathematical cognition from over 500 children aged 6 months to 8 years by compiling data from five published studies with unpublished data from longitudinal records. We targeted three key milestones of numerical development: numerosity perception, culturally trained counting, and formal and informal elementary mathematics concepts. In addition to testing for statistical differences between boys’ and girls’ mean performance and variability, we also tested for statistical equivalence between boys’ and girls’ performance. Across all stages of numerical development, analyses consistently revealed that boys and girls do not differ in early quantitative and mathematical ability. These findings indicate that boys and girls are equally equipped to reason about mathematics during early childhood. For our overseas readers, we then present the insights from this paper in Spanish, French, Portuguese, and German
Kiler Ridge Olive Oil Farm
Gregg Bone, a Cal Tech trained engineer, is a serial entrepreneur who has started 13 successful businesses, mostly in the tech industry. After a bicycle trip through Tuscany, his wife Audrey wanted to plant 40 olive trees in their backyard, which Gregg thought would be an expensive hobby. Better to plant 835 trees on a 58 acre property near Paso Robles, CA, in 2010. Five years later Gregg modified and installed an Italian olive mill for his own olives and as a custom crush operation. As a craft olive oil business, they marketing similarly to how neighboring wineries market their wine
Near Infrared Activity Close to the Crab Pulsar Correlated with Giant Gamma-ray Flares
We describe activity observed in the near-infrared correlated with a giant gamma-ray flare in the Crab Pulsar. The Crab Pulsar has been observed by the Fermi and AGILE satellites to flare for a period of 3 to 7 days, once every 1-1.5 years, increasing in brightness by a factor of 3-10 between 100MeV and 1GeV. We used Keck NIRC2 laser guide star adaptive optics imaging to observe the Crab Pulsar and environs before and during the March 2013 flare. We discuss the evidence for the knot as the location of the flares, and the theoretical implications of these observations. Ongoing target-of-opportunity programs hope to confirm this correlation for future flares
Aplicación del estudio del trabajo para mejorar la productividad en el área de PDI del almacén gloria de la Empresa Ransa Comercial, Lima Perú 2016
En la investigación titulada: “Aplicación del estudio del trabajo para mejorar la
productividad en el área logĂstica de PDI del almacĂ©n gloria de la empresa Ransa
Comercial Callao, 2016”,con el objetivo de determinar que al aplicar el estudio del
trabajo mejorarĂa la productividad en el proceso de acondicionamiento de autos.
La investigación es cuantitativa y de tipo aplicada, el diseño es causi
experimental.
La población está representada por el registro de producción donde se encuentra
la programaciĂłn de la cantidad de acondicionamientos de autos en periodos
mensuales. Los datos de la investigaciĂłn se obtienen por medio de la aplicaciĂłn
del estudio de métodos y medición del trabajo que serán las dimensiones de
nuestra variable independiente. La contrastaciĂłn de hipĂłtesis se realizĂł mediante
la prueba de normalidad de Wilcoxon
Los resultados obtenidos por la prueba de Wilcoxon demuestran que al aplicar el
estudio de trabajo se mejora la productividad en el proceso de acondicionamiento
con un incremento del 33%, con la aplicación del estudio de métodos un
incremento de la eficacia de 8% y con la mediciĂłn los movimientos se
incrementa la eficiencia de una media de 15 traslados a una de media de 11
traslados
Se concluye que la aplicaciĂłn de la variable independiente: el estudio del trabajo
mejora a la variable dependiente: productividad en el proceso de
acondicionamiento de autos del área de PDI de Ransa Comercial
Upaya Meningkatkan Kesadaran Higiene Personal Masyarakat dan Menjamin Kesejahteraan Hewan Ternak dalam Menghadapi Pandemi Covid-19
Thematic community service program which are located in Neglasari and Purwasari villages, Dramaga sub-district, Bogor district has been going well. Several program activities are carried out including the prevention and handling of Covid-19 which aims to prepare the people of Neglasari and Purwasati villages to face the Covid -19 pandemic. The next program is improving the welfare of farmer groups and livestock health, namely a demonstration of how to make probiotics for livestock through a video and poster which is socialized through the WhatsApp communication group. Another program is “ibu cerdas anak sehat” which aims to educate mothers about zoonotic diseases that are often ignored, such as toxoplasma and ringworm and is implemented by distributing leaflets to mothers who attend posyandu.
Keywords: COVID-19, Neglasari, Purwasari, Probiotic, Zoonose
Surface tuning of wood via covalent modification of its lignocellulosic biopolymers with substituted benzoates: a study on reactivity, efficiency, and durability
Chemical modification of wood applying benzo-
triazolyl-activated carboxylic acids has proven to be a versatile method for the durable functionalization of its lignocellulosic biopolymers. Through this process, the material properties of wood can be influenced and specifically optimized. To check the scope and limitations of this modification method, various benzamide derivatives with electron-withdrawing (EWG) or electron-donating (EDG) functional groups in different positions of the aromatic ring were synthesized and applied for covalent modification of Scots pine (Pinus sylvestris L.) sapwood in this study. The bonded amounts of substances (up to 2.20 mmol) were compared with the reactivity constants of the Hammett equation, revealing a significant correlation between the modification efficiency and the theoretical reactivity constants of the corresponding aromatic substitution pattern. The successful covalent attachment of the respective substituted benzamides was proven by attenuated total reflection infrared (ATR-IR) spectroscopy, while the stability of the newly formed ester bond was proven in a standardized leaching test
POLG2 deficiency causes adult-onset syndromic sensory neuropathy, ataxia and parkinsonism
Objective: Mitochondrial dysfunction plays a key role in the pathophysiology of neurodegenerative disorders such as ataxia and Parkinson's disease. We describe an extended Belgian pedigree where seven individuals presented with adult-onset cerebellar ataxia, axonal peripheral ataxic neuropathy, and tremor, in variable combination with parkinsonism, seizures, cognitive decline, and ophthalmoplegia. We sought to identify the underlying molecular etiology and characterize the mitochondrial pathophysiology of this neurological syndrome.
Methods: Clinical, neurophysiological, and neuroradiological evaluations were conducted. Patient muscle and cultured fibroblasts underwent extensive analyses to assess mitochondrial function. Genetic studies including genome-wide sequencing were conducted.
Results: Hallmarks of mitochondrial dysfunction were present in patients' tissues including ultrastructural anomalies of mitochondria, mosaic cytochrome c oxidase deficiency, and multiple mtDNA deletions. We identified a splice acceptor variant in POLG2, c.970-1G>C, segregating with disease in this family and associated with a concomitant decrease in levels of POLG2 protein in patient cells.
Interpretation: This work extends the clinical spectrum of POLG2 deficiency to include an overwhelming, adult-onset neurological syndrome that includes cerebellar syndrome, peripheral neuropathy, tremor, and parkinsonism. We therefore suggest to include POLG2 sequencing in the evaluation of ataxia and sensory neuropathy in adults, especially when it is accompanied by tremor or parkinsonism with white matter disease. The demonstration that deletions of mtDNA resulting from autosomal-dominant POLG2 variant lead to a monogenic neurodegenerative multicomponent syndrome provides further evidence for a major role of mitochondrial dysfunction in the pathomechanism of nonsyndromic forms of the component neurodegenerative disorders
Trophic Dynamics of the Boreal Forests of the Kluane Region
The trophic dynamics of the Yukon boreal forest have been under investigation at the Kluane Lake Research Station since 1973. We monitored and conducted experiments on the major species in this ecosystem, except the large mammals (for logistic reasons). The central problem has been to determine the causes of the 9 – 10 year cycle of snowshoe hares, and to achieve this we carried out several large-scale experiments manipulating food supplies, predator pressure, and soil nutrient availability to test hypotheses that food, predation, or habitat quality regulate populations. The hare cycle is driven top-down by predators, and most hares die because they are killed by predators. Predators also cause stress in female hares, and the stress response seems to be responsible for the loss of reproductive potential in the decline and low phases of the hare cycle. Many of the specialist predators and some herbivores in this ecosystem fluctuate with the hare cycle. Arctic ground squirrels do, but red squirrels do not, being linked closely to white spruce seed masting years. Small rodents fluctuate in numbers in two patterns. Red-backed voles and four species of Microtus voles have a 3 – 4 year cycle that seems to be driven by food supplies and social behaviour. Deer mice, in contrast, have fluctuated dramatically in the 38 years we have monitored them, but not cyclically. White spruce seed production varies with temperature and rainfall, but was not affected by adding nutrients in fertilizer. Global warming and reduced hare browsing in the last 20 years have helped to increase the abundance of shrubs in these forests. It will be challenging to predict how this system will change as climatic warming proceeds, because even closely related species in the same trophic level respond differently to perturbations. We recommend continued monitoring of the major species in these boreal forests.La dynamique trophique de la forêt boréale du Yukon fait l’objet d’une étude à la station de recherche du lac Kluane depuis 1973. Nous avons fait des expériences et surveillé les espèces importantes de cet écosystème, sauf en ce qui a trait aux principaux mammifères (pour des raisons de logistique). Le problème central a consisté à déterminer les causes du cycle de 9 à 10 ans du lièvre d’Amérique. Pour ce faire, nous avons effectué plusieurs expériences à grande échelle dans le cadre desquelles nous avons manipulé les disponibilités alimentaires, la pression exercée par les prédateurs et la disponibilité en nutriments dans le sol afin de mettre à l’épreuve les hypothèses selon lesquelles la nourriture, la prédation ou la qualité de l’habitat régularisent les populations. Le cycle du lièvre est dicté par les prédateurs de haut en bas, et la plupart des lièvres meurent parce qu’ils sont tués par les prédateurs. Par ailleurs, les prédateurs sont une source de stress chez les lièvres femelles, et la réaction au stress semble responsable de la perte de capacité de reproduction dans la phase du déclin et la phase basse du cycle du lièvre. Grand nombre des prédateurs spécialistes et certains herbivores de cet écosystème fluctuent en fonction du cycle du lièvre. C’est le cas du spermophile arctique, mais ce n’est pas le cas de l’écureuil roux, car il est étroitement lié aux années de paisson de graines d’épinette blanche. Le nombre de petits rongeurs fluctue en fonction de deux modèles. Le campagnol à dos roux et quatre espèces de campagnols Microtus ont un cycle de trois à quatre ans qui semble dicté par les disponibilités alimentaires et le comportement social, tandis que la souris sylvestre a connu d’énormes fluctuations pendant les 38 années qui ont fait l’objet d’une surveillance, sans toutefois afficher de cycles. La production de graines d’épinette blanche varie en fonction des températures et des chutes de pluie, mais n’a pas été influencée par l’ajout de nutriments au fertilisant. Le réchauffement planétaire et le broutage réduit des lièvres ces 20 dernières années ont aidé à accroître l’abondance d’arbustes dans ces forêts. Il sera difficile de prévoir comment ce système changera au fur et à mesure du réchauffement climatique, car même les espèces étroitement liées du même niveau trophique réagissent aux perturbations de manière différente. Nous recommandons la surveillance continue des principales espèces de ces forêts boréales
Exploration of copper oxide nanoneedle electrosynthesis applied in the degradation of methylene blue
In this study, we report a low cost, fast and unexplored electrochemical synthesis strategy of copper oxide nanoneedles films as well as their morphological and chemical characterization. The nanostructured films were prepared using electrochemical anodization in alkaline electrolyte solutions of ethylene glycol, water and fluoride ions. The film morphology shows nanoneedle-shaped structures, with lengths up to 1–2 µm; meanwhile, high-resolution X-ray photoelectron spectroscopy (HRXPS) and spectroscopy Raman analyses indicate that a mixture of Cu(II) and Cu(I) oxides, or only Cu(I) oxide, is obtained as the percentage of water in the electrolyte solution decreases. A preliminary study was also carried out for the photocatalytic degradation of the methylene blue (MB) dye under irradiation with simulated sunlight in the presence of the nanoneedles obtained, presenting a maximum degradation value of 88% of MB and, thus, demonstrating the potential characteristics of the material investigated in the degradation of organic dyes.Fil: OyarzĂşn, Diego P.. Universidad de Atacama.; ChileFil: Tello, Alejandra. Universidad de Atacama.; ChileFil: Sánchez, Julio. Universidad de Santiago de Chile; ChileFil: Boulett, AndrĂ©s. Universidad de Santiago de Chile; ChileFil: Linarez PĂ©rez, Omar Ezequiel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones en FĂsico-quĂmica de CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Instituto de Investigaciones en FĂsico-quĂmica de CĂłrdoba; ArgentinaFil: Martin-Trasanco, Rudy. Universidad Tecnologica Metropolitana; ChileFil: Pizarro, Guadalupe Del C.. Universidad Tecnologica Metropolitana; ChileFil: Flores, Marcos. Universidad de Chile; ChileFil: Zúñiga, CĂ©sar. Universidad de Las AmĂ©ricas.; Ecuado
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