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81.
82.
Obesity adversely affects myocardial metabolism, efficiency, and diastolic function. Our objective was to determine whether weight loss can ameliorate obesity-related myocardial metabolism and efficiency derangements and that these improvements directly relate to improved diastolic function in humans. We studied 30 obese (BMI >30 kg/m2) subjects with positron emission tomography (PET) (myocardial metabolism, blood flow) and echocardiography (structure, function) before and after marked weight loss from gastric bypass surgery (N = 10) or moderate weight loss from diet (N = 20). Baseline BMI, insulin resistance, hemodynamics, left ventricular (LV) mass, systolic function, myocardial oxygen consumption (MVO2), and fatty acid (FA) metabolism were similar between the groups. MVO2/g decreased after diet-induced weight loss (P = 0.009). Total MVO2 decreased after dietary (P = 0.02) and surgical weight loss (P = 0.0006) and was related to decreased BMI (P = 0.006). Total myocardial FA utilization decreased (P = 0.03), and FA oxidation trended lower (P = 0.06) only after surgery. FA esterification and LV efficiency were unchanged. After surgical weight loss, LV mass decreased by 23% (Doppler-derived) E/E' by 33%, and relaxation increased (improved) by 28%. Improved LV relaxation related significantly to decreased BMI, insulin resistance, total MVO2, and LV mass but not FA utilization. Decreased total MVO(2) predicted LV relaxation improvement independent of BMI change (P = 0.02). Weight loss can ameliorate the obesity-related derangements in myocardial metabolism and LV structure and diastolic function. Decreased total MVO2 independently predicted improved LV relaxation, suggesting that myocardial oxygen metabolism may be mechanistically important in determining cardiac relaxation.  相似文献   
83.
Like cities, forests grow by spreading out or by growing denser. Both inventories taken steadily by a single nation and other inventories gathered recently from many nations by the United Nations confirm the asynchronous effects of changing area and of density or volume per hectare. United States forests spread little after 1953, while growing density per hectare increased national volume and thus sequestered carbon. The 2010 United Nations appraisal of global forests during the briefer span of two decades after 1990 reveals a similar pattern: A slowing decline of area with growing volume means growing density in 68 nations encompassing 72% of reported global forest land and 68% of reported global carbon mass. To summarize, the nations were placed in 5 regions named for continents. During 1990-2010 national density grew unevenly, but nevertheless grew in all regions. Growing density was responsible for substantially increasing sequestered carbon in the European and North American regions, despite smaller changes in area. Density nudged upward in the African and South American regions as area loss outstripped the loss of carbon. For the Asian region, density grew in the first decade and fell slightly in the second as forest area expanded. The different courses of area and density disqualify area as a proxy for volume and carbon. Applying forestry methods traditionally used to measure timber volumes still offers a necessary route to measuring carbon stocks. With little expansion of forest area, managing for timber growth and density offered a way to increase carbon stocks.  相似文献   
84.
Survival typically contributes most to population trends in long‐lived birds and its accurate estimation is therefore vital for population management and conservation. We evaluated the effects of age, territoriality and reproduction on survival in Bonelli’s Eagle Aquila fasciata through multistate capture‐mark‐recapture analyses on a long‐term dataset. Monitoring was carried out in southeast France (1990–2008) and involved the surveying of territorial Eagles, the marking of fledged chicks, and the recording of resightings and recoveries of marked non‐territorial and territorial birds. Survival improved with age, but territoriality was not retained in the best model; yearly survival was estimated at 0.479 for fledglings (to 1 year of age), 0.570 for 1‐ and 2‐year‐olds, and 0.870 for 3‐year‐old and older individuals. The second best model supported a further increase in survival from 3‐year‐olds (0.821) to older individuals (0.880). In the third best supported model, territoriality enhanced survival, but only in 2‐year‐olds (0.632 vs. 0.562 for non‐territorial). We found no correlation between the previous breeding stage and future survival, consistent with the long lifespan of the study species. Nevertheless, 4‐year‐old and older successful breeders were more likely to breed the following year than failed adult breeders (0.869 vs. 0.582), suggesting that the cost of reproduction is small in comparison with the variation in quality among individuals or their territories.  相似文献   
85.
Abstract: The Jurassic was an important period in the evolution of Testudinata and encompasses the origin of many clades, and this is especially true of Jurassic turtles from Western Europe. A new genus and species of Late Jurassic turtle, Hispaniachelys prebetica gen. et sp. nov. from the upper Oxfordian of the Prebetic (Southern Spain), is described on the basis of postcranial material. The specimen is the only known tetrapod from the Mesozoic of the Prebetic and the oldest turtle from southern Europe. A mosaic of characters indicates this is a new genus: it displays basal features including dorsal epiplastral processes/reduced cleithra, no medial contact of the extragulars and a long first thoracic rib, alongside derived characters including an absence of mesoplastra and the vertebral 3/4 sulcus crossing neural 5. The phylogenetic position of the new taxon is hard to resolve, and it might be either a paracryptodire or a basal testudine, but it is distinct from Plesiochelys. A complex taphonomic history is shown by a range of overlying grazing traces and bioerosion on the carapace. The carapace was subsequently overturned and buried ventrally up, terminating grazing activity, and was then bored by sponges before final burial. Scanning electron microscopy reveals phosphatic microspheroids associated with bacterial decay in the vascular cavities of the cancellous bone, suggesting the carapace may have acted as a closed microenvironment in which decay‐derived authigenic minerals formed.  相似文献   
86.
The decreasing cost of whole-genome and whole-exome sequencing has resulted in a renaissance for identifying Mendelian disease mutations, and for the first time it is possible to survey the distribution and characteristics of these mutations in large population samples. We conducted carrier screening for all autosomal-recessive (AR) mutations known to be present in members of a founder population and revealed surprisingly high carrier frequencies for many of these mutations. By utilizing the rich demographic, genetic, and phenotypic data available on these subjects and simulations in the exact pedigree that these individuals belong to, we show that the majority of mutations were most likely introduced into the population by a single founder and then drifted to the high carrier frequencies observed. We further show that although there is an increased incidence of AR diseases overall, the mean carrier burden is likely to be lower in the Hutterites than in the general population. Finally, on the basis of simulations, we predict the presence of 30 or more undiscovered recessive mutations among these subjects, and this would at least double the number of AR diseases that have been reported in this isolated population.  相似文献   
87.
The history of some invasive species is so complex that their origins can be difficult to determine. One example of such invasive species is the California invasive known as “wild artichoke thistle” (Cynara cardunculus var. sylvestris), found in natural and disturbed ecosystems. Wild artichoke thistle is a Mediterranean native and the progenitor of two domesticated horticultural taxa, artichoke and cardoon. Different hypotheses regarding the origins of California plants have included introductions by 19th century Italian immigrants and the de-domestication (evolutionary reversion to wild-type morphology) of feral (escaped, free-living) cultivars. Using microsatellite markers, we compared the genetic constitutions of 12 artichoke thistle populations in California with possible progenitor populations: 17 Spanish and Italian wild populations and eight different artichoke and cardoon cultivars. Each California population was compared with its putative progenitors using STRUCTURE analysis. Our results suggest that California's artichoke thistle populations are polyphyletic. Surprisingly, two-thirds of California's populations closely matched populations from the Iberian Peninsula. Three populations matched domesticated artichoke. One population appears to have wild and cultivar hybrid ancestry. Alleles specific to Italian populations were found at low frequencies in some California plants, suggesting that Italian wild plants may have been in California, but have left a trivial genetic legacy. Given that the de-domesticated plants in this study appear to be as invasive as the wild taxon, we conclude with a discussion of the role that ferality and de-domestication may have in plant invasions.  相似文献   
88.
The inclusion of dry beans in diets has clear health benefits. However, consumers in developed countries mainly choose beans for their sensory qualities, especially for their texture. This article describes the constitution, training and validation of a panel of judges to evaluate the texture of dry beans. The judges were trained in the perception of different textures, analyzed a wide range of beans and selected seed-coat roughness, seed-coat perceptibility and creaminess/mealiness of the cotyledon as the main attributes to be scored. After training, the panel was capable of discriminating between different varieties of beans and even between beans of the same variety grown at different locations. The analysis of the behavior of the panel in a standard tasting session 2 years after its formation showed that periodic inclusion of samples from the extremes of the scales for the attributes during tasting sessions was sufficient to keep the panel trained.

PRACTICAL APPLICATIONS


This article could serve as a guide for the training of sensory panels to evaluate the texture of dry beans. It describes the selection of the attributes on which the analysis is based, references for the extreme values of the attributes and how to train the panel. It also provides a practical example of the analysis of the behavior of the panel some time after training.  相似文献   
89.
Far-red-emitting cyanine fluorochromes have many properties desirable for in vivo imaging: absorption and emission at wavelengths where blood and tissue are relatively transparent, high quantum yields, and good solubility even at high molar ratios of fluorochrome to antibody. Potentially, conjugation by multiple linkages should minimize hydrolysis in vivo. We conjugated two tumor-targeting monoclonal antibodies: anti-SSEA-1 (IgM, ) at ratios of 1.2–35 mol dye/mol antibody and 9.2.27 (IgG2a, ) at 0.6–6 mol dye/mol antibody, using the cyanine fluorochromes Cy3.18, Cy5.18, and Cy5.5.18. Nude mice were inoculated using the SSEA-1-expressing MH-15 teratocarcinoma or the 9.2.27 antigen-expressing SK-MEL-2 melanoma to give tumors at several sites. Conjugated antibody was injected, and mice were imaged immediately after injection and at appropriate intervals thereafter using a standard camera lens, dissecting microscope, or endoscopes. Images were acquired using either an image-intensified video camera or cooled CCD cameras. Immediately after injection, major blood vessels and the heart, liver, and kidneys were readily visualized. After 1 day, tumor-targeting antibody conjugates were concentrated in tumors and there was little circulating conjugate; however, the bladder and kidneys were still visible. Tumors labeled by specific antibody were the most fluorescent tissues at 2 days after injection, but non-specific antibody conjugates did not concentrate in the tumors. The small intestine was weakly visualized by both specific and non-specific antibody conjugates. These data support the possibility of visualizing tumor metastasis by optical means, including currently available endoscopes.This work was supported by funds of the Division of Urologic Surgery, Department of Surgery, University of Pittsburgh; by an NSF Center Grant (MCB-8920118) to the Center for Light Microscope Imaging and Biotechnology, Carnegie-Mellon University; and by intramural funds of the VAMC  相似文献   
90.
Two simple methods were followed to determine detection thresholds for the taste of substances in aqueous solution. The methods applied were: a modification of the ascending method of limits and a method based on the use of scales. Detection thresholds were calculated for the four basic tastes (sweet, salty, acid, and bitterness), umami and metallic. Reference substances for each taste were sucrose, sodium chloride, citric acid, caffeine, monosodium glutamate and iron (II) sulfate heptahydrate and the results of the two methods were compared. We found that the threshold values calculated by method ASTM-679 was within the range of concentrations identified with the scales method.  相似文献   
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