Encouraging the use of the x-ray machine by the individual dentist

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Demographic Responses To Famines In South Asia

Summary This article examines demographic responses to major famines in the Indian subcontinent, including the Bengal famine of 1943–44, the Bangladesh famine of 1974–75 and food crises in Bihar and Maharashtra. It argues that while a decline in conceptions (and, subsequently, births) is a prompt and virtually universal response to famine situations, the relationship of a rise in death rates to circumstances of famine is both much more complex and less certain. Increases in mortality due to famine ? when they occur ? are conditioned not just by food problems, but also by an array of factors such as current patterns of disease, migration, relief and rainfall. Knowledge about the normal prevailing seasonal distribution of mortality is especially helpful in anticipating when famine death rates may rise. Relatedly, information about malaria and rainfall regimes can also be particularly important. The article also addresses famine mortality differentials according to their patterns by age and sex. Study of neglected historical data sources underscores the complexity and interrelated nature of the main elements ? fertility, mortality and migration ? of famine demography. Resumé Les Résponses Démographiques A La Famine En Asie Du Sud Le présent article examine les réponses démographiques face aux famines majeures qui se sont déclarées dans le sous?continent indien, y compris la famine de 1943–44 au Bengale; la famine de 1974–75 au Bangladesh; et les crises d'approvisionnement alimentaire dans les états du Bihar et du Maharashtra. L'auteur estime que, si une diminution dans le taux de conceptions (et, par la suite, de naissances) est une réponse rapide et pratiquement universelle aux cas de famine, le rapport entre les augmentations dans le taux de mortalité et ces cas de famine est un phénomène à la fois bien plus complexe ? et beaucoup moins certain. Les augmentations dans le taux de mortalité dues à la famine, lorsque celle?ci se déclare, ont pour préconditions non seulement les problèmes de l'alimentation mais aussi, tout un éventail d'autres facteurs tels que les mouvements dans les taux de maladie; la migration; la lutte contre la famine; et la hauteur des précipitations. Une connaissance de la distribution saisonnière normale ? pour la period sous considération ? des taux de mortalité est surtout utile si l'on veut essayer d'anticiper à quel stade les taux de mortalité dûs à la famine seront susceptibles de s'élever. Parallèlement, les renseignements concernant le paludisme et les pronostics de hauteur des précipitations seront éventuellement tout aussi importantes. Le présent article s'adresse également aux différentiels de mortalité par la famine en termes de leurs tranches d'age et en termes des genres. Une étude des sources négligées de données historiques sert à souligner la complexité et l'interdépendance des principaux éléments de la démographie de la famine: la fertilité, la mortalité et la migration. Resumen Respuestas Demográficas Al Problema Del Hambre En Asia Del Sur Este artículo examina las respuestas demográficas a las peores situaciones de hambre en el sub?continente indio, incluyendo la crisis de Bengal en 1943–1944, la de Bangladesh en 1974–1975, y otras crisis de alimentos en Bihar y Maharashtra. Se argumenta que si bien la declinación en cincepciones (y, subsecuentemente, nacimientos) es una respuesta immediata y vitualmente universal a las situaciones de hambre, la relación entre el aumento de tasas de mortalidad y las circunstancias de hambre es a la vez mucho más compleja y mucho menos segura. El incremento en la mortalidad como consecuencia del hambre ? cuando ocurre ? está condicionado no sólo por problemas de alimentos, sino también por una serir de factores como los patrones de enfermedad, migración, ayuda externa y cantidad de illuvia. El conocimiento de la distribución predominante de la mortalidad de acuerdo a la época del año ayuda especialmente para anticipar el momento en que las tasas de mortalidad por hambre pueden aumentar. En conexión con ésto último, la información sobre malaria y regímenes de cantidad de lluvia puede ser también particularmente importante. El artículo también explora las diferenciales en la mortalidad por hambre de acuerdo a la edad y al sexo. El estudio de fuentes de datos históricamente relegados subraya la complejidad y naturaleza interrelacionada de los prioncipales elementos de la demografía del hambre: fertilidad, mortalidad y migración

Force-velocity relation and density profiles for biased diffusion in an adsorbed monolayer

In this paper, which completes our earlier short publication [Phys. Rev. Lett. 84, 511 (2000)], we study dynamics of a hard-core tracer particle (TP) performing a biased random walk in an adsorbed monolayer, composed of mobile hard-core particles undergoing continuous exchanges with a vapor phase. In terms of an approximate approach, based on the decoupling of the third-order correlation functions, we obtain the density profiles of the monolayer particles around the TP and derive the force-velocity relation, determining the TP terminal velocity, V_{tr}, as the function of the magnitude of external bias and other system's parameters. Asymptotic forms of the monolayer particles density profiles at large separations from the TP, and behavior of V_{tr} in the limit of small external bias are found explicitly.Comment: Latex, 31 pages, 3 figure

NADPH and glutathione redox link TCA cycle activity to endoplasmic reticulum homeostasis

Many metabolic diseases disrupt endoplasmic reticulum (ER) homeostasis, but little is known about how metabolic activity is communicated to the ER. Here, we show in hepatocytes and other metabolically active cells that decreasing the availability of substrate for the tricarboxylic acid (TCA) cycle diminished NADPH production, elevated glutathione oxidation, led to altered oxidative maturation of ER client proteins, and attenuated ER stress. This attenuation was prevented when glutathione oxidation was disfavored. ER stress was also alleviated by inhibiting either TCA-dependent NADPH production or Glutathione Reductase. Conversely, stimulating TCA activity increased NADPH production, glutathione reduction, and ER stress. Validating these findings, deletion of the Mitochondrial Pyruvate Carrier-which is known to decrease TCA cycle activity and protect the liver from steatohepatitis-also diminished NADPH, elevated glutathione oxidation, and alleviated ER stress. Together, our results demonstrate a novel pathway by which mitochondrial metabolic activity is communicated to the ER through the relay of redox metabolites

Lizards Cooperatively Tunnel to Construct a Long-Term Home for Family Members

Constructing a home to protect offspring while they mature is common in many vertebrate groups, but has not previously been reported in lizards. Here we provide the first example of a lizard that constructs a long-term home for family members, and a rare case of lizards behaving cooperatively. The great desert skink, Liopholis kintorei from Central Australia, constructs an elaborate multi-tunnelled burrow that can be continuously occupied for up to 7 years. Multiple generations participate in construction and maintenance of burrows. Parental assignments based on DNA analysis show that immature individuals within the same burrow were mostly full siblings, even when several age cohorts were present. Parents were always captured at burrows containing their offspring, and females were only detected breeding with the same male both within- and across seasons. Consequently, the individual investments made to construct or maintain a burrow system benefit their own offspring, or siblings, over several breeding seasons

Metabarcoding clarifies the diet of the elusive and vulnerable Australian tjakura (Great Desert Skink, Liopholis kintorei)

Introduction: Accurately quantifying the diet of species has implications for our understanding of their ecology and conservation. Yet, determining the dietary composition of threatened and elusive species in the wild is often difficult. Methods: This study presents the first dietary assessment of tjakura (Liopholis kintorei) using non-invasive sampling of scats and high-throughput sequencing techniques. Results: The tjakura in Uluru consumed 48 invertebrates, 27 plants, and two vertebrate taxa. Fruit flies (Leucophenga spp.), beetles (Harpalus spp. and Omorgus spp.), mosquitos (Culicidae spp.), termites (Termitidae spp.), spiked mallow (Malvastrum americanum), bush tomatoes (Solanum centrale), and wild turnip (Brassica tournefortii) comprised the majority of the diet. Analysis of similarity revealed that food items did not differ significantly between tjakura age groups, seasons, or time since the last fire, however, adults, hot season, and fire scar of 2018 showed a relatively higher prey diversity. Discussion: These high similarities in diet composition between age classes and fire scars indicate potential intraspecific competition when food resources are scarce. The diet diversity and potential plasticity observed in this study reflect a dietary ecology influenced by food availability rather than preference. Our study demonstrates that scat DNA metabarcoding is an important complementary tool to conventional scat analysis or indigenous knowledge as most food items we identified were previously not recorded through those methods

Electrochemical and Photoelectrochemical Investigation of Water Oxidation with Hematite Electrodes

Atomic layer deposition (ALD) was utilized to deposit uniform thin films of hematite (α-Fe2O3) on transparent conductive substrates for photocatalytic water oxidation studies. Comparison of the oxidation of water to the oxidation of a fast redox shuttle allowed for new insight in determining the rate limiting processes of water oxidation at hematite electrodes. It was found that an additional overpotential is needed to initiate water oxidation compared to the fast redox shuttle. A combination of electrochemical impedance spectroscopy, photoelectrochemical and electrochemical measurements were employed to determine the cause of the additional overpotential. It was found that photogenerated holes initially oxidize the electrode surface under water oxidation conditions, which is attributed to the first step in water oxidation. A critical number of these surface intermediates need to be generated in order for the subsequent hole-transfer steps to proceed. At higher applied potentials, the behavior of the electrode is virtually identical while oxidizing either water or the fast redox shuttle; the slight discrepancy is attributed to a shift in potential associated with Fermi level pinning by the surface states in the absence of a redox shuttle. A water oxidation mechanism is proposed to interpret these results

Demonstartion of density dependence of x-ray flux in a laser-driven hohlraum

Experiments have been conducted using laser-driven cylindrical hohlraums whose walls are machined from Ta{sub 2}O{sub 5} foams of 100 mg/cc and 4 g/cc densities. Measurements of the radiation temperature demonstrate that the lower density walls produce higher radiation temperatures than the high density walls. This is the first experimental demonstration of the prediction that this would occur [M. D. Rosen and J. H. Hammer, Phys. Rev. E 72, 056403 (2005)]. For high density walls, the radiation front propagates subsonically, and part of the absorbed energy is wasted by the flow kinetic energy. For the lower wall density, the front velocity is supersonic and can devote almost all of the absorbed energy to heating the wall

Description of a strain from an atypical population of Aspergillus parasiticus that produces aflatoxins B only, and the impact of temperature on fungal growth and mycotoxin production

In this study, an atypical strain of Aspergillus parasiticus is described. This strain, reported from Portuguese almonds, was named Aspergillus parasiticus B strain. The strain is herein characterised at the morphological and physiological levels, and compared with the typical A. parasiticus strain and other similar species in section Flavi. Previously published morphological and molecular data support that the B strain is very closely related to the A. parasiticus type strain. However, while A. parasiticus typically produces aflatoxins B and G, B strain produces aflatoxins B only. Furthermore, this atypical strain showed to differ from the typical strain in the fact that higher growth (colony diameter) and strain. This strain can become a major food safety concern in colder regions where the typical A. parasiticus strains are not well adapted.NORTE-07-0124-FEDER-000028PEst-OE/EQB/LA0023/2013PEst-OE/AGR/UI0690/201

Developing a Series of AI Challenges for the United States Department of the Air Force

Through a series of federal initiatives and orders, the U.S. Government has been making a concerted effort to ensure American leadership in AI. These broad strategy documents have influenced organizations such as the United States Department of the Air Force (DAF). The DAF-MIT AI Accelerator is an initiative between the DAF and MIT to bridge the gap between AI researchers and DAF mission requirements. Several projects supported by the DAF-MIT AI Accelerator are developing public challenge problems that address numerous Federal AI research priorities. These challenges target priorities by making large, AI-ready datasets publicly available, incentivizing open-source solutions, and creating a demand signal for dual use technologies that can stimulate further research. In this article, we describe these public challenges being developed and how their application contributes to scientific advances