170 research outputs found

    Recent Environmental Changes in the Arctic: A Review

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    Numerous recent observations indicate that the Arctic is undergoing a significant change. In the last decade, the hydrography of the Arctic Ocean has shifted, and the atmospheric circulation has undergone a change from the lower stratosphere to the surface. Typically the eastern Arctic Ocean, on the European side of the Lomonosov Ridge, is dominated by water of Atlantic origin. A cold halocline of varying thickness overlies the warmer Atlantic water and isolates it from the sea ice and surface mixed layer. The western Arctic Ocean, on the North American side of the Lomonosov Ridge, is characterized by an added layer of water from the Pacific immediately below the surface mixed layer. Data collected during several cruises from 1991 to 1995 indicate that in the 1990s the boundary between these eastern and western halocline types shifted from a position roughly parallel to the Lomonosov Ridge to near alignment with the Alpha and Mendeleyev Ridges. The Atlantic Water temperature has also increased, and the cold halocline has become thinner. The change has resulted in increased surface salinity in the Makarov Basin. Recent results suggest that the change also includes decreased surface salinity and greater summer ice melt in the Beaufort Sea. Atmospheric pressure fields and ice drift data show that the whole patterns of atmospheric pressure and ice drift for the early 1990s were shifted counterclockwise 40°-60° from earlier patterns. The shift in atmospheric circulation seems related to the Arctic Oscillation in the Northern Hemisphere atmospheric pressure pattern. The changes in the ocean circulation, ice drift, air temperatures, and permafrost can be explained as responses to the Arctic Oscillation, as can changes in air temperatures over the Russian Arctic. De nombreuses observations effectuées récemment indiquent qu'un changement majeur est en train de se produire dans l'Arctique. Au cours des dix dernières années, l'hydrographie de l'océan Arctique s'est déplacée et la circulation atmosphérique a subi un changement, de la basse stratosphère à la surface. En général, l'océan Arctique oriental, du côté européen de la dorsale Lomonosov, est dominé par l'eau d'origine atlantique. Une halocline froide d'épaisseur variable est sus-jacente à l'eau atlantique plus chaude et l'isole de la glace marine et de la couche mixte de surface. L'océan Arctique occidental, du côté nord-américain de la dorsale Lomonosov, se caractérise par une couche supplémentaire d'eau du Pacifique située juste au-dessous de la couche mixte de surface. Les données recueillies au cours de plusieurs croisières de 1991 à 1995 indiquent que, dans les années 1990 la limite entre ces types d'haloclines de l'est et de l'ouest est passée d'une position plus ou moins parallèle à la dorsale Lomonosov, à un alignement presque parfait avec les dorsales Alpha et Mendeleyev. La température des eaux de l'Atlantique a également augmenté, et l'halocline froide s'est amincie. Ce changement a amené une augmentation de la salinité de surface dans le bassin de Makarov. De récents résultats suggèrent que le changement s'accompagne d'une diminution de la salinité de surface et d'une augmentation de la fonte estivale de la glace dans la mer de Beaufort. Les données barométriques et celles de la dérive des glaces montrent que tous les schémas de pression atmosphérique et de dérive des glaces pour les premières années de 1990 se sont déplacés de 40 à 60° par rapport aux précédents. Le déplacement dans la circulation atmosphérique semble lié à l'oscillation arctique dans le schéma de pression atmosphérique de l'hémisphère Nord. Les changements dans la circulation océanique, la dérive des glaces, la température de l'air et le pergélisol peuvent s'expliquer comme une réponse à l'oscillation arctique, tout comme les changements dans la température de l'air au-dessus de l'Arctique russe.

    Are Sand or Composted Bedding Cubicles Suitable Alternatives to Rubber Matting for Housing Dairy Cows?

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    PICO questionIn [Dairy Cow Management] do [Sand OR composted bedding] compared with [rubber matting] result in [fewer disease incidence] consequences?Clinical bottom lineClean, deep-bedded sand appears to be associated with the best outcomes in clinical mastitis, cow cleanliness, subclinical mastitis, cow lying times, hock lesions and cow preference. Recycled sand, composted manure and other deep-bedded systems also appear to have increased cow comfort and hygiene indices versus mattress systems. Deep-bedded, composted manure systems can also have better outcomes concerning Gram positive and negative bacterial growth versus straw and mattress systems as long as they are kept clean and renewed frequently.  <img src="https://www.veterinaryevidence.org/rcvskmod/icons/pr-icon.jpg" alt="Peer Reviewed" /

    Identifying significant contributors to milk production in the absence of the Herd Size Effect

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    Prior to the commencement of deregulation from 1 July 2000, the Australian Dairy Research and Development Corporation conducted a large-scale telephone survey of 1826 Australian dairy farms to examine the current on-farm management practices in relation to milk production and farm and farmer demographics. The questionnaire results from the 214 dairy farms in the sub-tropical region of South East Queensland and Northern New South Wales were analysed (Zamykal et al. 2007) to uncover those significant inputs that affect milk production

    Global REACH: Assessment of brady-arrhythmias in Andeans and Lowlanders during apnea at 4330m

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    BACKGROUND: Ascent to altitude increases the prevalence of arrhythmogenesis in low-altitude dwelling populations (Lowlanders). High altitude populations (ie. Nepalese Sherpa) may have arrhythmias resistant adaptations that prevent arrhythmogenesis at altitude, though this has not been documented in other High altitude groups, including those diagnosed with chronic mountain sickness (CMS). We investigated whether healthy (CMS-) and CMS afflicted (CMS+) Andeans exhibit cardiac arrhythmias under acute apneic stress at altitude. METHODS AND RESULTS: Electrocardiograms (lead II) were collected in CMS- (N=9), CMS+ (N=8), and Lowlanders (N= 13) following several days at 4330m (Cerro de Pasco, Peru). ECG rhythm and HR were assessed at both rest and during maximal volitional apnea (End-Expiratory [EXP]). Both CMS- and CMS+ had similar basal HR (69 ± 8 beats/min vs. 62 ± 11 beats/min), while basal HR was higher in Lowlanders (77 ± 18 beats/min; P<0.05 versus CMS+). Apnea elicited significant bradycardia (nadir -32 ± 15 beats/min; P<0.01) and the development of arrhythmias in 8/13 Lowlanders (junctional rhythm, 3° atrio-venticular block, sinus pause). HR was preserved was prior to volitional breakpoint in both CMS- (nadir -6 ± 1 beat/min) and CMS+ (1 ±12 beats/min), with 2/17 Andeans developing arrhythmias ( 1 CMS+ and 1 CMS-; both Premature Atrial Contraction) prior to breakpoint. CONCLUSIONS: Andeans showed an absence of arrhythmias and preserved HR response to volitional apnea at altitude, demonstrating that potential cardio-resistant adaptations to arrhythmogenesis exist across permanent HA populations. Acclimatized Lowlanders have further demonstrated an increased prevalence of arrhythmias at altitude

    Menstrual Justice: A Human Rights Vision for Australia

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    In the past year alone, news reports have shown how menstrual injustice is linked to gender inequality, a lack of economic opportunity, poor health outcomes, and human rights violations. Here is a small sampling of the unjust treatment of women and other people who menstruate: locked bathrooms at schools, inadequate supply of free period products, harmful menstruation-avoidance options for athletes, the human and economic costs of the lack of menstruation and menopause employment leave policies, and the mistreatment of people imprisoned who menstruate. To improve women’s equality, we need menstrual justice. Menstrual justice is the achievement of dignity, liberty and equality for people who menstruate, primarily cis women and girls but also transgender men and boys, genderqueer/nonbinary and intersex persons. On the other hand, menstrual injustice is the oppression of people who menstruate simply because they menstruate, and our society does not yet accept and accommodate menstruation as normal. Menstrual injustices can compound the marginalization of persons already subject to other injustices, including young students, low-income persons, persons with disability, Indigenous persons, persons who are imprisoned, and remote and low-wage workers. We need laws that clearly outlaw workplace discrimination and harassment against menstruators, so no one is fired for bleeding on the job or being late to work due to period pain. We need public awareness campaigns and curricular expansion focused on health information and the eradication of menstrual stigma to curb poor menstrual health. We need access to resources and healthcare for residents in institutional settings that supports their autonomy over menstruation and menopause. We need provision of Indigenous intergenerational teaching about menstruation and menopause. Governments have addressed some of these menstrual injustices. For example, all States and Territories provide free product access in schools. Victoria will be providing free product access in public places. Such initiatives are critical and helpful. But they are isolated and do not tackle important pieces of the equality puzzle. The authors are a group of researchers, activists, and policy makers who have created this set of evidence-based recommendations for governments relating to menstruation and menopause. Our concrete recommendations, entitled “Menstrual Justice: A Human Rights Vision for Australia,” call upon Government to do more to fully address menstrual injustices. Our recommendations include the areas of public awareness, curriculum, schools, workplaces, public buildings and housing, institutional settings and discrimination and coercion. Many of these recommendations are no cost or low cost but could have a large impact on gender equality and would improve human rights for women and other people who menstruate
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