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Pesticide Acute Toxicity Is a Better Correlate of U.S. Grassland Bird Declines than Agricultural Intensification  [PDF]
Pierre Mineau, Mélanie Whiteside
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0057457
Abstract: Common agricultural birds are in decline, both in Europe and in North America. Evidence from Europe suggests that agricultural intensification and, for some species, the indirect effects of pesticides mediated through a loss of insect food resource is in part responsible. On a state-by-state basis for the conterminous Unites States (U.S.), we looked at several agronomic variables to predict the number of grassland species increasing or declining according to breeding bird surveys conducted between 1980 and 2003. Best predictors of species declines were the lethal risk from insecticide use modeled from pesticide impact studies, followed by the loss of cropped pasture. Loss of permanent pasture or simple measures of agricultural intensification such as the proportion of land under crop or the proportion of farmland treated with herbicides did not explain bird declines as well. Because the proportion of farmland treated with insecticides, and more particularly the lethal risk to birds from the use of current insecticides feature so prominently in the best models, this suggests that, in the U.S. at least, pesticide toxicity to birds should be considered as an important factor in grassland bird declines.
Age-Dependent Terminal Declines in Reproductive Output in a Wild Bird  [PDF]
Martijn Hammers, David S. Richardson, Terry Burke, Jan Komdeur
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0040413
Abstract: In many iteroparous species individual fitness components, such as reproductive output, first increase with age and then decline during late-life. However, individuals differ greatly in reproductive lifespan, but reproductive declines may only occur in the period just before their death as a result of an age-independent decline in physiological condition. To fully understand reproductive senescence it is important to investigate to what extent declines in late-life reproduction can be explained by age, time until death, or both. However, the study of late-life fitness performance in natural populations is challenging as the exact birth and death dates of individuals are often not known, and most individuals succumb to extrinsic mortality before reaching old age. Here, we used an exceptional long-term longitudinal dataset of individuals from a natural, closed, and predator-free population of the Seychelles warbler (Acrocephalus sechellensis) to investigate reproductive output, both in relation to age and to the time until the death of an individual (reverse-age approach). We observed an initial age-dependent increase in reproductive output that was followed by a decline in old age. However, we found no significant decline in reproductive output in the years directly preceding death. Although post-peak reproductive output declined with age, this pattern differed between terminal and non-terminal reproductive attempts, and the age-dependence of the terminal breeding attempt explained much of the variation in age-specific reproductive output. In fact, terminal declines in reproductive output were steeper in very old individuals. These results indicate that not only age-dependent, but also age-independent factors, such as physiological condition, need to be considered to understand reproductive senescence in wild-living animals.
Declines of Aerial Insectivores in North America Follow a Geographic Gradient  [cached]
Silke Nebel,Alex Mills,Jon D. McCracken,Philip D. Taylor
Avian Conservation and Ecology , 2010, DOI: 10.5751/ace-00391-050201
Abstract: North American birds that feed on aerial insects are experiencing widespread population declines. An analysis of the North American Breeding Bird Survey trend estimates for 1966 to 2006 suggests that declines in this guild are significantly stronger than in passerines in general. The pattern of decline also shows a striking geographical gradient, with aerial insectivore declines becoming more prevalent towards the northeast of North America. Declines are also more acute in species that migrate long distances compared to those that migrate short distances. The declines become manifest, almost without exception, in the mid 1980s. The taxonomic breadth of these downward trends suggests that declines in aerial insectivore populations are linked to changes in populations of flying insects, and these changes might be indicative of underlying ecosystem changes.
Plausible Explanation Attempts against the Supraluminal Propagation of Light  [PDF]
Petra Schulz
Physics , 2006,
Abstract: The supposed supraluminal velocities of light are caused above all by interaction of matter with electromagnetic radiation from the sender and/or the own environment. Anti-Stokes frequencies which result in the consequence that the refractive index becomes less than 1 or negative during strong optical laser stimulation even are emitted in a increased manner under suitable conditions. The light propagation is retarded simultaneously by interaction within the matter. The velocity of light remains a limiting speed which can not be exceeded. The refractive index is defined in a new manner and a simple collision theory presented for impacts between photon and corpuscle. ----- Die vermeintlichen Ueberlichtgeschwindigkeiten werden vor allem durch Wechselwirkung der Materie mit der elektromagnetischen Strahlung aus dem Sender bzw. aus der eigenen Umgebung verursacht. Es werden unter geeigneten Bedingungen vermehrt anti-Stokessche Frequenzen emittiert, die zur Folge haben, dass die Brechzahl kleiner als 1 oder bei starker Laseranregung sogar negativ wird. Gleichzeitig wird durch die Wechselwirkung innerhalb der Materie die Lichtausbreitung gebremst. Die Lichtgeschwindigkeit bleibt eine Grenzgeschwindigkeit, die nicht ueberschritten werden kann. Die Brechzahl wird neu definiert und eine einfache Stosstheorie fuer Stoesse zwischen Photon und Teilchen vorgestellt.
Plausible explanation of the $Δ_{5/2^{+}}(2000)$ puzzle  [PDF]
Ju-Jun Xie,A. Martínez Torres,E. Oset,P. González
Physics , 2011, DOI: 10.1103/PhysRevC.83.055204
Abstract: From a Faddeev calculation for the $\pi-(\Delta\rho)_{N_{5/2^{-}}(1675)}$ system we show the plausible existence of three dynamically generated $I(J^{P})=3/2 (5/2^{+})$ baryon states below 2.3 GeV whereas only two resonances, $\Delta_{5/2^{+}}(1905)(\ast\ast\ast\ast)$ and $\Delta_{5/2^{+}}(2000)(\ast\ast),$ are cataloged in the Particle Data Book Review. Our results give theoretical support to data analyses extracting two distinctive resonances, $\Delta_{5/2^{+}}(\sim1740)$ and $\Delta_{5/2^{+}}(\sim2200),$ from which the mass of $\Delta_{5/2^{+}}(2000)(\ast\ast)$ is estimated. We propose that these two resonances should be cataloged instead of $\Delta_{5/2^{+}}(2000).$ This proposal gets further support from the possible assignment of the other baryon states found in the approach in the $I=1/2,3/2$ with $J^{P}=1/2^{+},3/2^{+},5/2^+$ sectors to known baryonic resonances. In particular, $\Delta_{1/2^{+}}(1750)(\ast)$ is naturally interpreted as a $\pi N_{1/2^{-}}(1650)$ bound state.
Comparison of the components of breeding bird communities in the grasslands of Inner Mongolia, China
内蒙古草原繁殖鸟类群聚组成之比较

YEN Chung Wei,
颜重威

生态学报 , 2000,
Abstract: A census of breeding birds was carried out in the vegetation of steppe, typical grassland, wet grassland, sand grassland, and mountain forest grassland in May, 1998 in the temperate steppe of Inner Mongolia, China. Eleven 100 hm 2 plots with three transect lines , each 150m apart, were studied. Meanwhile, 1m 2 of vegetation within each plot was used for recording plant species, vertical height, coverage, and weight.As the results indicated, the numbers of species of breeding birds in the grasslands of Inner Mongolia were low. There were 4~6 species in steppe, 5~8 species in typical grassland, 15 species in wet grassland, 9~12 species in sand grassland, and 6 species in mountain forest grassland. Bird species diversity and richness index were also low. In descending order were sand grassland, wet grassland, mountain forest grassland, typical grassland, and steppe. Bird densities in order from large to small were wet grassland, typical grassland, steppe, sand grassland, and mountain forest grassland. As for the food habit distributions of breeding birds, in the steppe and typical grassland omnivores were dominant, in the wet grassland insectivores were dominant, in the sand grassland omnivores and carnivores were dominant, and in the mountain forest grassland insectivores and omnivores, followed by carnivores were dominant.
Effects of the insecticide  [PDF]
STELA STOYANOVA,ELENKA GEORGIEVA,ILIANA VELCHEVA,VESELA YANCHEVA
Journal of BioScience and Biotechnology , 2012,
Abstract: The main goal of the present work is to study the effects of the new neonicotinoid insecticide Actara 25 WG" on the intensity of expression of glycogen in the liver of common carp (Cyprinus carpio L.) by using PAS-reaction on cryosections. Common carp is an economically important fish species, which is widely used as a bioindicator for the health of freshwater basins since it could also survive at very contaminated sites. We have used 6.6 mg/L, 10 mg/L and 20 mg/L of the test chemical under laboratory conditions. The results demonstrated that the intensity of staining of the PAS-reaction is directly proportional to the increasing concentration of the insecticide. In addition, this indicates that the amount of glycogen in hepatocytes also increased. Conglomerates of accumulated glycogen in certain hepatocytes were found at the highest concentration of the insecticide. Therefore, we consider that under the influence of Actara 25 WG" the process of glyconeogenesis in the liver of the studied fish accelerates.
Cognitive Declines Precede and Predict Functional Declines in Aging and Alzheimer’s Disease  [PDF]
Laura B. Zahodne, Jennifer J. Manly, Anna MacKay-Brandt, Yaakov Stern
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0073645
Abstract: Objective To investigate the temporal ordering of cognitive and functional declines separately in older adults with or without Alzheimer’s disease (AD). Design and Setting A community-based longitudinal study of aging and dementia in Northern Manhattan (Washington Heights/Hamilton Heights Inwood Columbia Aging Project) and a multicenter, clinic-based longitudinal study of prevalent AD at Columbia University Medical Center, Johns Hopkins School of Medicine, Massachusetts General Hospital, and the H?pital de la Salpêtrière in Paris, France (the Predictors Study). Participants 3,443 initially non-demented older adults (612 with eventual incident dementia) and 517 patients with AD. Main Outcome Measures Cognitive measures included the modified Mini-Mental State Exam and composite scores of memory and language derived from a standardized neuropsychological battery. Function was measured with the Blessed Dementia Rating Scale, completed by the participant (in the sample of non-demented older adults) or an informant (in the sample of prevalent AD patients). Data were analyzed with autoregressive cross-lagged panel analysis. Results Cognitive scores more consistently predicted subsequent functional abilities than vice versa in non-demented older adults, participants with eventual incident dementia, and patients with prevalent AD. Conclusions Cognitive declines appear to precede and cause functional declines prior to and following dementia diagnosis. Standardized neuropsychological tests are valid predictors of later functional changes in both non-demented and demented older adults.
A plausible explanation for male dominance in typhoid ileal perforation
Khan M
Clinical and Experimental Gastroenterology , 2012, DOI: http://dx.doi.org/10.2147/CEG.S36569
Abstract: plausible explanation for male dominance in typhoid ileal perforation Commentary (784) Total Article Views Authors: Khan M Published Date November 2012 Volume 2012:5 Pages 213 - 217 DOI: http://dx.doi.org/10.2147/CEG.S36569 Received: 01 August 2012 Accepted: 07 October 2012 Published: 12 November 2012 Mohammad Khan Department of Microbiology, College of Medicine, Chichiri, Blantyre, Malawi Abstract: The phenomenon of consistent male dominance in typhoid ileal perforation (TIP) is not well understood. It cannot be explained on the basis of microbial virulence, Peyer's patch anatomy, ileal wall thickness, gastric acidity, host genetic factors, or sex-linked bias in hospital attendance. The cytokine response to an intestinal infection in males is predominantly proinflammatory as compared with that in females, presumably due to differences in the sex hormonal milieu. Sex hormone receptors have been detected on lymphocytes and macrophages, including on Peyer's patches, inflammation of which (probably similar to the Shwartzman reaction/Koch phenomenon) is the forerunner of TIP, and is not excluded from the regulatory effects of sex hormones. Hormonal control of host-pathogen interaction may override genetic control. Environmental exposure to Salmonella typhi may be more frequent in males, presumably due to sex-linked differences in hygiene practices and dining-out behavior. A plausible explanation of male dominance in TIP could include sex-linked differences in the degree of natural exposure of Peyer's patches to S. typhi. An alternative explanation may include sexual dimorphism in host inflammatory response patterns in Peyer's patches that have been induced by S. typhi. Both hypotheses are testable.
Plausible Explanation of Quantization of Intrinsic Redshift from Hall Effect and Weyl Quantization
Smarandache F.,Christianto V.
Progress in Physics , 2006,
Abstract: Using phion condensate model as described by Moffat [1], we consider a plausible explanation of (Tifft) intrinsic redshift quantization as described by Bell [6] as result of Hall effect in rotating frame. We also discuss another alternative to explain redshift quantization from the viewpoint of Weyl quantization, which could yield Bohr-Sommerfeld quantization.
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