geographic variation

地理变异
  • 文章类型: Journal Article
    目前的指南建议针对射血分数降低的心力衰竭同时开始多药指南指导的药物治疗类别。
    本研究的目的是评估县级使用三联指导药物治疗的差异,定义为β受体阻滞剂的同时处方填充,肾素-血管紧张素系统抑制剂或血管紧张素受体脑啡肽抑制剂,和盐皮质激素受体拮抗剂,射血分数降低的心力衰竭。
    我们使用医疗保险按服务收费索赔数据进行了一项队列研究(A部分,B,和D在2013年至2019年之间)。县的特点,包括地区层面的贫困指标,employment,通过使用三联疗法的五分位数比较了受教育程度和患者水平的社会人口统计学和病史变量。构建了多水平Logistic回归模型来估计各县聚类的上下文效应,以中位数OR表示。
    来自2,600个县(美国所有县的83%)的304,857名患者被包括在内。三联疗法使用的中位数为14.3%(IQR:10.3%-18.8%),所包括的县差异很大(范围:0%-54.5%)。与使用率最高的五分之一的县相比,三联疗法使用率最低的五分位数的县的社会经济地位的地区水平指标较差(%失业率6.8%vs6.2%).最低五分之一的县的黑人患者比例更高(最高五分之一的13.3%比5.7%),低收入补贴的患者比例更高(最高五分之一的29.3%比25.8%)。中位OR为1.30(95%CI:1.28-1.33)。
    我们观察到美国各县使用三联疗法的差异,与社会经济劣势指标相关的局部使用模式欠佳。
    UNASSIGNED: Current guidelines recommend simultaneous initiation of multidrug guideline-directed medical therapy classes for heart failure with reduced ejection fraction.
    UNASSIGNED: The purpose of this study was to evaluate county-level variation in use of triple guideline-directed medical therapy, defined as simultaneous prescription fills for beta-blockers, renin-angiotensin system inhibitors or angiotensin receptor neprilysin inhibitors, and mineralocorticoid receptor antagonists, in heart failure with reduced ejection fraction.
    UNASSIGNED: We conducted a cohort study using Medicare Fee-for-Service claims data (parts A, B, and D between 2013 and 2019). Features of counties including area-level indicators of poverty, employment, and educational attainment and aggregated patient-level sociodemographic and medical history variables were compared by quintiles of triple therapy use. A multilevel logistic regression model was constructed to estimate the contextual effect of clustering by counties, which was expressed as a median OR.
    UNASSIGNED: 304,857 patients from 2,600 counties (83% of all U.S. counties) were included. The median for triple therapy use was 14.3% (IQR: 10.3%-18.8%) across included counties with a wide variation (range: 0%-54.5%). Compared to counties in the highest use quintile, counties in lowest triple therapy use quintile had worse area-level indicators of socioeconomic status (% unemployment 6.8% vs 6.2%). Counties in lowest quintile had higher proportion of Black patients (13.3% vs 5.7% in highest quintile) and patients with low-income subsidy (29.3% vs 25.8% in highest quintile). The median OR was 1.30 (95% CI: 1.28-1.33).
    UNASSIGNED: We observed variation in triple therapy use across counties in the United States with suboptimal local use patterns correlating with indicators of socioeconomic disadvantage.
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  • 文章类型: Journal Article
    许多历史工作都集中在建立地理和生态规则,以广泛解释大小变化的模式。我们使用几何形态计量学和空间统计学检查了斑点鬣狗头骨大小的地理变化。我们量化了头骨的大小变化和性别大小二象性,并评估了温度的影响,降水,土地覆盖类型,和人口密度对头骨大小的影响。我们发现雌性斑点鬣狗平均比雄性稍大。我们对区域差异的分析并未表明性别大小二态性的地理差异。斑点鬣狗的头骨大小随地理位置而变化,但不遵守伯格曼规则。男女最小的个体出现在-5.00°至10.00°和东经28.50°之间,在其他地方发现了更大的个体。尽管斑点鬣狗头骨的大小在某些观点上与栖息地类型和气候指标等变量共同变化,该物种的头骨大小与人口密度的变化最强烈。最高的人口密度与最小的头骨大小有关,可能反映了人口密度高和资源获取之间的关系。这些结果表明,与Bergmann规则相比,能量等效规则可以更好地解释斑点鬣狗头骨大小的地理变化。
    Much historic work has focused on establishing geographical and ecological rules that broadly explain patterns in size variation. We examined geographic variation in Spotted Hyena skull size using geometric morphometrics and spatial statistics. We quantified size variation and sexual size dimorphism of the skull, and evaluated the influence of temperature, precipitation, land cover type, and population density on skull size. We found that female spotted hyenas are slightly larger on average than males. Our analysis of regional differences did not indicate geographic variation in sexual size dimorphism. Skull size of Spotted Hyenas varies with geography but does not adhere to Bergmann\'s Rule. The smallest individuals of both sexes occur between -5.00° and 10.00° latitude and east of 28.50° longitude, with larger individuals being found elsewhere. Although Spotted Hyena skull size co-varies in some views with such variables as habitat type and climate indicators, skull size in this species most strongly co-varies with population density. The highest population densities are associated with the smallest skull size, possibly reflecting a relationship between high population density and access to resources. These results suggest that geographic variation in Spotted Hyena skull size is better explained by the energetic equivalence rule than Bergmann\'s Rule.
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  • 文章类型: Journal Article
    目的:与射血分数降低的心力衰竭(HF)相比,保留射血分数的HF(HFpEF),射血分数轻度降低的HF(HFmrEF)的患病率正在增加,然而,对患者特征的地理变化知之甚少,这两种HF表型的治疗和结果。这项研究的目的是调查HFpEF和HFmrEF的地理差异。
    结果:我们对来自北美(NA)的5项纳入HFpEF或HFmrEF患者的临床试验进行了个体患者分析,拉丁美洲(LA),西欧(WE),中欧/东欧和俄罗斯(CEER)亚太地区(AP)。我们使用描述性统计和多变量回归模型比较了地区。在19959名患者中,4066(23.1%)患有HFmrEF,15353(76.9%)患有HFpEF。无论HF表型如何,我们的病人年龄最大,和那些在CEER最小的人。LA的女性比例最大,NA的黑人患者最多。肥胖和糖尿病在NA中最普遍,高血压和冠心病在CEER中最常见。自我报告的健康状况差异惊人,在NA中最差,在AP中最好。在HFmrEF患者中,主要复合终点(心血管死亡或HF住院)的发生率为:NA12.56/100患者年(/100py),AP11.67/100py,CEER10.12/100py,LA8.90/100py,和我们8.43/100py,由HF住院率的差异驱动。HFpEF的相应值为11.47/100py,7.80/100py,5.47/100py,5.92/100py,和7.80/100py,分别。
    结论:患者特征存在很大的地理差异,HFpEF和HFmrEF患者的治疗和预后。这些发现对试验结果的解释和概括性有影响,设计和进行未来的试验,并优化这些患者的护理。
    OBJECTIVE: Compared to heart failure (HF) with reduced ejection fraction, HF with preserved ejection fraction (HFpEF), and HF with mildly reduced ejection fraction (HFmrEF) are increasing in prevalence, yet little is known about the geographic variation in patient characteristics, treatments and outcomes among these two HF phenotypes. The aim of this study was to investigate geographic differences in HFpEF and HFmrEF.
    RESULTS: We conducted an individual patient analysis of five clinical trials enrolling patients with HFpEF or HFmrEF from North America (NA), Latin America (LA), Western Europe (WE), Central/Eastern Europe and Russia (CEER), and Asia-Pacific (AP). We compared regions using descriptive statistics and multivariable regression models. Among the 19 959 patients included, 4066 (23.1%) had HFmrEF and 15 353 (76.9%) HFpEF. Regardless of HF phenotype, patients from WE were oldest, and those in CEER youngest. LA had the largest portion of females and NA most black patients. Obesity and diabetes were most prevalent in NA and hypertension and coronary heart disease most common in CEER. Self-reported health status varied strikingly and was the worst in NA and best in AP. Among patients with HFmrEF, rates of the primary composite endpoint (cardiovascular death or HF hospitalization) were: NA 12.56 per 100 patient-years (/100py), AP 11.67/100py, CEER 10.12/100py, LA 8.90/100py, and WE 8.43/100py, driven by differences in the rate of HF hospitalization. The corresponding values in HFpEF were 11.47/100py, 7.80/100py, 5.47/100py, 5.92/100py, and 7.80/100py, respectively.
    CONCLUSIONS: There is substantial geographic variation in patient characteristics, treatment and outcomes among patients with HFpEF and HFmrEF. These findings have implications for interpretation and generalizability of trial results, design and conduct of future trials, and optimization of care for these patients.
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  • 文章类型: Journal Article
    树种的地理变异和驯化是森林引种理论的重要组成部分,种质资源的追踪是建立优质人工林的理论基础。油松(油松。)是中国北方广泛分布的重要乡土用材树种,但目前尚不清楚中国松树主要人工林种群的种质来源。这里,使用两个mtDNA标记,我们分析了代表35个种群的796个个体(matR标记),以及代表中国北方主要自然和人工种群38个种群(nad5-1标记)的873个人,分别(山西,河北省和辽宁省)。结果证实,自然SX*种群(\“*”表示自然种群)在中国北方油松种群中的核心地位,HB和LN人工林的遗传多样性高于自然SX*种群,在SX*和LN的群体中,遗传背景有很大的差异,HB显示了相反的情况。更重要的是,我们完成了HB和LN种植的“逐点跟踪”。结果表明,几乎所有HB种群都起源于SX*(GDS*,ZTS*,GCS*,andTHS*),这导致HB种群遗传背景的同质性。LN种植园的大部分种质来源于LN*(ZJS*和WF*),另一部分来自GDS*(SX*),导致LN群体内遗传背景的巨大差异。研究结果为科学分配提供了可靠的理论依据,管理,以及中国北方油松种群的利用,并促进油松人工林的高质量建立。
    The geographical variation and domestication of tree species are an important part of the theory of forest introduction, and the tracing of the germplasm is the theoretical basis for the establishment of high-quality plantations. Chinese pine (Pinus tabuliformis Carr.) is an important native timber tree species widely distributed in northern China, but it is unclear exactly where germplasm of the main Chinese pine plantation populations originated. Here, using two mtDNA markers, we analyzed 796 individuals representing 35 populations (matR marker), and 873 individuals representing 38 populations (nad5-1 marker) of the major natural and artificial populations in northern China, respectively (Shanxi, Hebei and Liaoning provinces). The results confirmed that the core position of natural SX* populations (\"*\" means natural population) in the Chinese pine populations of northern China, the genetic diversity of HB and LN plantations was higher than that of natural SX* populations, and there was a large difference in genetic background within the groups of SX* and LN, HB showed the opposite. More importantly, we completed the \"point by point\" tracing of the HB and LN plantings. The results indicated that almost all HB populations originated from SX* (GDS*, ZTS*, GCS*, and THS*), which resulted in homogeneity of the genetic background of HB populations. Most of germplasm of the LN plantations originated from LN* (ZJS* and WF*), and the other part originated from GDS* (SX*), resulting in the large differences in the genetic background within the LN group. Our results provided a reliable theoretical basis for the scientific allocation, management, and utilization of Chinese pine populations in northern China, and for promoting the high-quality establishment of Chinese pine plantations.
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  • 文章类型: Journal Article
    寄生虫感染的空间变化可能具有许多物理和生物驱动因素。发现这些驱动因素对于生态系统工程师的寄生虫尤其重要,因为工程师是他们社区的基础。牡蛎是一个重要的沿海生态系统工程师,在全球范围内急剧下降,部分原因是致命牡蛎病的病例增加,比如Dermo和MSX,由原生动物寄生虫Perkinsusmarinus和Laplosporidiumnelsoni引起,分别。除了水质和流体动力学,关于其他变量如何在区域范围内影响牡蛎中这些病原体的患病率和强度的信息很少。为了检查这些牡蛎寄生虫空间变异的驱动因素,包括宿主大小,当地的珊瑚礁属性,和景观属性——我们采样了24个系统地分布在佐治亚州海岸的珊瑚礁,美国。跨站点,我们发现至少有一种寄生虫的牡蛎患病率普遍很高(91.02%±8.89,平均值±SD).对于一个关键的生态系统工程师来说,高水平的寄生虫流行不仅是潜在的问题,而且低空间变异性可能会限制变量在区域范围内的解释能力。我们的统计模型解释了这些微寄生虫的患病率和强度的空间格局变化的18%至42%。有趣的是,景观环境是P.marinus的积极预测因子,而是H.Nelsoni的负面预测因子.总的来说,我们的研究结果表明,驱动寄生虫患病率和强度的因素在多个空间尺度上运作,相同的因素可以促进和阻碍同一宿主物种中的不同寄生虫。
    Spatial variation in parasitic infection may have many physical and biological drivers. Uncovering these drivers may be especially important for parasites of ecosystem engineers because the engineers are foundational to their communities. Oysters are an important coastal ecosystem engineer that have declined drastically worldwide, in part due to enhanced cases of lethal oyster diseases, such as Dermo and MSX, caused by the protozoan parasites Perkinsus marinus and Haplosporidium nelsoni, respectively. Besides water quality and hydrodynamics, there is little information on how other variables influence the prevalence and intensity of these pathogens in oysters across a regional scale. To examine drivers of spatial variation in these oyster parasites-including host size, local reef properties, and landscape properties-we sampled 24 reefs systematically spread along the coast of Georgia, USA. Across sites, we found universally high prevalence of oysters with at least one of these parasites (91.02% ± 8.89, mean ± SD). Not only are high levels of parasite prevalence potentially problematic for a pivotal ecosystem engineer, but also low spatial variability may limit the explanatory power of variables across a regional scale. Our statistical models explained between 18 and 42% of the variation in spatial patterns of prevalence and intensity of these microparasites. Interestingly, landscape context was a positive predictor of P. marinus, but a negative predictor of H. nelsoni. Overall, our findings suggest that factors driving parasite prevalence and intensity operate across multiple spatial scales, and the same factor can both facilitate and hinder different parasites within the same host species.
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  • 文章类型: Journal Article
    社交蜜蜂已经发展了复杂的通信系统,以招募新发现的食物来源的巢穴。根据环境或季节的不同,觅食范围可能从几百米到几公里不等,生活在不同气候区的社会蜂种种群可能在招募交流中表现出特定的适应性。因此,西方蜜蜂的研究,Apismellifera,表明与热带种群相比,温带种群的舞蹈校准曲线较浅。在这里,我们报告了三个印度A.cerana谱系的校准曲线的第一次比较:热带A.indica,和两个山地喜马拉雅人口A.C.cerana(喜马al尔邦)和A.C.kashmirensis(查谟和克什米尔)。我们发现,两个山地A.cerana种群的菌落显示出舞蹈距离校准曲线,其斜率明显低于热带A.in。接下来,我们将A.C.cerana菌落转移到班加罗尔(〜2600km外),以获得与A.indica相同位置的校准曲线。普通的花园实验证实了坡度的这种差异,暗示谱系在舞蹈距离编码中表现出遗传固定的差异。然而,转移的A.c.cerana菌落的校准曲线的斜率也显着高于喜马al尔邦测试的斜率,表明环境的重要影响。温带和热带A.cerana谱系之间的舞蹈距离编码差异类似于A.mellifera所描述的差异,这表明两个物种的populatiinons独立地进化了相似的适应性。
    Social bees have evolved sophisticated communication systems to recruit nestmates to newly found food sources. As foraging ranges can vary from a few hundred meters to several kilometers depending on the environment or season, populations of social bee species living in different climate zones likely show specific adaptations in their recruitment communication. Accordingly, studies in the western honey bee, Apis mellifera, demonstrated that temperate populations exhibit shallower dance-calibration curves compared with tropical populations. Here, we report the first comparison of calibration curves for three Indian Apis cerana lineages: the tropical Apis indica, and the two montane Himalayan populations Apis cerana cerana (Himachal Pradesh) and Apis cerana kashmirensis (Jammu and Kashmir). We found that the colonies of the two montane A. cerana populations show dance-distance calibration curves with significantly shallower slopes than those of the tropical A. indica. Next, we transferred A. c. cerana colonies to Bangalore (∼ 2600 km away) to obtain calibration curves in the same location as A. indica. The common garden experiment confirmed this difference in slopes, implying that the lineages exhibit genetically fixed differences in dance-distance coding. However, the slopes of the calibration curves of the transferred A. c. cerana colonies were also significantly higher than those of the colonies tested in their original habitat, indicating an important effect of the environment. The differences in dance-distance coding between temperate and tropical A. cerana lineages resemble those described for Apis mellifera, suggesting that populations of both species independently evolved similar adaptations.
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  • 文章类型: Journal Article
    表型可塑性,单一基因型在不同环境条件下产生不同表型的能力,在进化生物学的几个领域发挥着深远的作用。一个重要的作用是适应可变的环境。虽然可塑性在许多环境因素的反应中得到了很好的证明,有多少可塑性是适应性的争议。关于特定种群在可塑性性质上表现出质差异的频率的证据也是混合的。我们提供了来自南卡罗来纳州(SC)的三个当地相邻种群的雄性和雌性帆鱼(Poecilialatipinna)的生长和成熟对温度和盐度变化的反应规范的数据。我们将这些反应规范与先前在佛罗里达州北部(NF)的当地邻近人群中报道的反应规范进行了比较。总的来说,SC鱼的可塑性模式与NF鱼的可塑性模式相似。可塑性的大小不同;来自SC的鱼比来自NF的鱼显示出更小的可塑性。这是因为与NF鱼相比,SC鱼在较低的温度和盐度下生长更快,成熟更早。这是一种反梯度变化模式,其中SC鱼生长更快,成熟更早,否则会减缓生长和推迟成熟。在这两个地区的鱼类中,雄性的可塑性比雌性少得多,特别是在成熟时的长度。虽然来自NF的种群之间没有可检测到的异质性,来自SC人群之一的男性,离其他两个最远,与其他两个SC种群的雄性相比,成熟年龄对温度变化的反应在质量上不同。区域内和区域之间可塑性的种群变异模式表明基因流,随着赛芬·莫利斯的距离而减小,在限制反应规范的分歧中起着至关重要的作用。
    Phenotypic plasticity, the ability of a single genotype to produce different phenotypes under different environmental conditions, plays a profound role in several areas of evolutionary biology. One important role is as an adaptation to a variable environment. While plasticity is extremely well documented in response to many environmental factors, there is controversy over how much of that plasticity is adaptive. Evidence is also mixed over how often conspecific populations display qualitative differences in the nature of plasticity. We present data on the reaction norms of growth and maturation to variation in temperature and salinity in male and female sailfin mollies (Poecilia latipinna) from three locally adjacent populations from South Carolina (SC). We compare these reaction norms to those previously reported in locally adjacent populations from north Florida (NF). In general, patterns of plasticity in fish from SC were similar to those in fish from NF. The magnitude of plasticity differed; fish from SC displayed less plasticity than fish from NF. This was because SC fish grew faster and matured earlier at the lower temperatures and salinities compared to NF fish. This is a countergradient pattern of variation, in which SC fish grew faster and matured earlier in conditions that would otherwise slow growth and delay maturity. Among fish from both regions, males were much less plastic than females, especially for length at maturity. While there was no detectable heterogeneity among populations from NF, males from one of the SC populations, which is furthest from the other two, displayed a qualitatively different response in age at maturity to temperature variation than did males from the other two SC populations. The pattern of population variation in plasticity within and among regions suggests that gene flow, which diminishes with distance in sailfin mollies, plays a critical role in constraining divergence in norms of reaction.
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  • 文章类型: Journal Article
    目的:钠-葡萄糖协同转运蛋白2抑制剂(SGLT2is)和胰高血糖素样肽-1受体激动剂(GLP-1RAs)改善2型糖尿病(T2D)患者的血糖控制和心肾结局。然而,使用中的地理和社会经济差异还没有得到很好的理解。
    方法:我们确定了367829名年龄≥40岁的新南威尔士州居民在2020年分配二甲双胍作为T2D的代表。我们估计了T2D患者中使用其他降糖药物的患病率,以及同时使用T2D治疗(即二甲双胍+另一种降糖药物)的患者中使用SGLT2i和GLP-1RA的患病率。我们通过小规模地理来衡量患病率,按年龄组分层,以偏远和社会经济地位为特征。
    结果:SGLT2i(29.7%)和GLP-1RA(8.3%)在40-64岁的T2D人群中的使用率随着地域偏远和社会经济劣势更大的地区而增加,类似于其他降糖药物。SGLT2i(55.4%)和GLP-1RA(15.4%)在使用T2D治疗的人群中的患病率因地理区域而异。在不利地区和GLP-1RA使用率较高的局部地区,SGLT2i使用率较低(中位数的2.5倍)。与40-64岁的人相比,SGLT2i和GLP-1RA的使用在老年组的患病率较低,但在不同地理区域具有相似的变化模式。
    结论:SGLT2i和GLP-1RA的使用因地域而异,可能反映了系统和处方水平因素的组合。GLP-1RA使用的社会经济差异被局部处方模式所掩盖。持续监测变化可以帮助制定干预措施,以优化受益最大的人群的使用。
    OBJECTIVE: Sodium-glucose cotransporter 2 inhibitors (SGLT2is) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) improve glycaemic control and cardio-renal outcomes for people with type 2 diabetes (T2D). However, geographic and socio-economic variation in use is not well understood.
    METHODS: We identified 367 829 New South Wales residents aged ≥40 years who dispensed metformin in 2020 as a proxy for T2D. We estimated the prevalence of use of other glucose-lowering medicines among people with T2D and the prevalence of SGLT2i and GLP-1RA use among people using concomitant T2D therapy (i.e. metformin + another glucose-lowering medicine). We measured the prevalence by small-level geography, stratified by age group, and characterized by remoteness and socio-economic status.
    RESULTS: The prevalence of SGLT2i (29.7%) and GLP-1RA (8.3%) use in people with T2D aged 40-64 increased with geographic remoteness and in areas of greater socio-economic disadvantage, similar to other glucose-lowering medicines. The prevalence of SGLT2i (55.4%) and GLP-1RA (15.4%) among people using concomitant T2D therapy varied across geographic areas, with lower SGLT2i use in more disadvantaged areas and localized areas of high GLP-1RA use (2.5 times the median). Compared with people aged 40-64 years, the prevalence of SGLT2i and GLP-1RA use was lower in older age groups, but with similar patterns of variation across geographic areas.
    CONCLUSIONS: The prevalence of SGLT2i and GLP-1RA use varied by geography, probably reflecting a combination of system- and prescriber-level factors. Socio-economic variation in GLP-1RA use was overshadowed by localized patterns of prescribing. Continued monitoring of variation can help shape interventions to optimize use among people who would benefit the most.
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  • 文章类型: Journal Article
    与募集相关的种子性状直接影响植物的适应性和持久性。了解种子性状变异的关键模式和影响因素有助于评估植物定殖和生境选择。然而,尽管灌木物种的关键种子性状在高山沙漠生态系统中起着至关重要的作用,但它们的变异模式通常被低估和忽视。
    这项研究收集了整个青藏高原21个中央紫草种群的种子,分析种子性状的地理格局,以识别外部环境影响。此外,它探索了种子形态和养分如何影响发芽胁迫耐受性,阐明形成种子性状变异的直接和间接因素。
    结果显示了中流星种子性状的大量种内变异。除种子长宽比(LWR)外,种子性状均随地理梯度而显着变化。此外,本研究验证了气候变量和土壤养分对种子性状的直接和间接影响。气候主要影响种子养分,和土壤养分显著影响种子形态和种子养分。此外,气候直接影响种子萌发耐旱指数(GDTI)和萌发耐盐碱指数(GSTI)。种子萌发耐冷指数(GCTI)受气候和土壤养分(主要是SOC)的影响。GDTI和GSTI受种子形态(主要是种子千粒重(TGW))的显著影响,GCTI受种子营养成分(主要是可溶性蛋白(CSP)含量)的影响明显。
    本研究结果充分说明了高寒荒漠生态系统灌木的种子性状变异规律,对理解灌木适应高山沙漠生态系统的机制具有重要意义,预测环境变化的结果,并告知保护工作。该研究可为青藏高原高寒荒漠生态系统的管理提供有价值的参考。
    UNASSIGNED: Seed traits related to recruitment directly affect plant fitness and persistence. Understanding the key patterns and influencing factors of seed trait variations is conducive to assessing plant colonization and habitat selection. However, the variation patterns of the critical seed traits of shrub species are usually underrepresented and disregarded despite their vital role in alpine desert ecosystems.
    UNASSIGNED: This study gathered seeds from 21 Asterothamnus centraliasiaticus populations across the Qinghai-Tibetan Plateau, analyzing geographical patterns of seed traits to identify external environmental influences. Additionally, it explored how seed morphology and nutrients affect germination stress tolerance, elucidating direct and indirect factors shaping seed trait variations.
    UNASSIGNED: The results present substantial intraspecific variations in the seed traits of A. centraliasiaticus. Seed traits except seed length-to-width ratio (LWR) all vary significantly with geographic gradients. In addition, the direct and indirect effects of climatic variables and soil nutrients on seed traits were verified in this study. Climate mainly influences seed nutrients, and soil nutrients significantly affect seed morphology and seed nutrients. Furthermore, climate directly impacts seed germination drought tolerance index (GDTI) and germination saline-alkali tolerance index (GSTI). Seed germination cold tolerance index (GCTI) is influenced by climate and soil nutrients (mostly SOC). GDTI and GSTI are prominently influenced by seed morphology (largely the seed thousand-grain weight (TGW)), and GCTI is evidently affected by seed nutrients (mainly the content of soluble protein (CSP)).
    UNASSIGNED: The findings of this study amply explain seed trait variation patterns of shrubs in alpine desert ecosystems, possessing significant importance for understanding the mechanism of shrub adaptation to alpine desert ecosystems, predicting the outcomes of environmental change, and informing conservation efforts. This study can be a valuable reference for managing alpine desert ecosystems on the Qinghai-Tibetan Plateau.
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  • 文章类型: Journal Article
    虽然自1990年代以来,住院皮肤科的执业时间有所减少,对住院皮肤病学的现状知之甚少。我们描述了2013年至2019年间为美国医疗保险人群服务的住院皮肤病学的分布和频率。对2013年至2019年公开提供的住院医疗保险B部分索赔数据进行了横断面分析。主要结果和措施是皮肤科医生进行住院接触的特征和趋势。使用χ2分析比较分类变量。使用皮尔逊相关系数分析线性趋势。782名医生符合纳入标准。皮肤科医生更常见的是男性(56.5%),拥有对抗疗法医学博士学位(MD)(86.3%),在大都市环境中(98.2%)。然而,女性住院皮肤科医生的比例显着增加(37.9%至46.2%)。在农村和大都市的实践中,住院医生数量(2013年:356;2019年:281)和发生皮肤科的医疗中心数量(2013年:239;2019年:157)减少,在非居民相关机构中更重要。空间分析显示,广泛的地区缺乏符合定义标准的皮肤科医生。限制包括需要纳入10次Medicare住院患者,没有报告数据的县。总之,每年进行>10次住院的皮肤科医生数量正在减少,美国住院皮肤科就诊的数量存在很大差异。
    While time spent practicing inpatient dermatology has decreased since the 1990s, less is known about the current state of inpatient dermatology. We describe the distribution and frequency of inpatient dermatology encounters servicing the United States Medicare population between 2013 and 2019. Cross-sectional analysis of publicly available inpatient Medicare Part B claims data from 2013 to 2019 was conducted. Main outcomes and measures were characteristics and trends of dermatologists performing inpatient encounters. Categorical variables were compared using χ2 analysis. Trends were analyzed for linearity using Pearson correlation coefficient. 782 physicians met inclusion criteria for inclusion. Dermatologists were more often male (56.5%), possessing allopathic Medical Doctorate (MD) (86.3%), and in metropolitan settings (98.2%). However, proportion of female inpatient dermatologists increased significantly (37.9% to 46.2%). Across rural and metropolitan practices, number of inpatient physicians (2013: 356; 2019: 281) and number of medical centers in which dermatology encounters occurred (2013: 239; 2019: 157) decreased, more significantly in non-residency-associated institutions. Spatial analysis revealed wide regions lacking dermatologists meeting defined criteria. Limitations included the need for ten Medicare inpatient encounters for inclusion, counties without reported data. In conclusion, the number of dermatologists performing > 10 inpatient encounters per year is decreasing, and large variations exist in the number of U.S. inpatient dermatology visits.
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