long-term study

长期研究
  • 文章类型: Journal Article
    去蛋白牛骨(DBB)被广泛用作上颌窦底增强(MSFA)手术中的骨替代物。以前的研究没有显示使用DBB时增强骨的长期体积变化。选择的患者使用侧窗技术和异种移植物进行MFSA,单独或与患者的下颌骨自体骨结合。锥形束计算机断层扫描(CBCT)图像用于比较患者在6年或更长时间内增强骨骼的体积变化。在植入牙齿后7个月和6年或更长时间后比较MSFA时,在骨增强区域未见明显的骨减少。
    Deproteinised bovine bone (DBB) is widely used as bone substitute in maxillary sinus floor augmentation (MSFA) surgery. No previous studies have shown the long-term volumetric changes in the augmented bone when using DBB. The selected patients had MFSA performed using a lateral window technique and a xenograft, alone or in combination with the patient\'s autologous bone from the mandible. Cone beam computed tomography (CBCT) images were used to compare the volumetric changes in the augmented bone for patients over a period of 6 or more years. No significant bone reduction was seen in the augmented bone region when comparing MSFA after 7 months and 6 or more years after dental implantation.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    由于不断的变化和生物多样性的下降,今天的科学应该依靠长期的基于物种的生态研究。我们对水甲虫科进行了长期的生态动力学研究,which,尽管它在底栖群落中非常丰富,仍然缺乏研究。这项研究的主要目的是调查人口方面(组成,多样性,性别比例)和生态方面(出现模式,PlitviceLakesNP15年以上的Scirtidae家族的季节性动态和对环境因素的偏好,克罗地亚。该研究在三个地点和五种不同的底物类型中进行。在研究区域中总共记录了三个具有不同分布的分类单元:在凝灰岩屏障和Elodessp。在春季地区。在春季和初夏,性别比对男性有利,而在秋末,它转向了对女性的青睐。家庭的丰富和出现主要取决于环境参数,这些参数在15年内表现出最大的波动:水温,水排放和氧饱和度。我们的结果清楚地表明,Scirtidae可以用作河流分区和栖息地质量的指标。根据本研究的方法和结果,我们得出结论,应在东南欧喀斯特淡水栖息地的未来监测和保护措施中使用Scirtidae。
    Due to ongoing changes and a decline in biodiversity, science today should rely on long-term species-based ecological studies. We have conducted a long-term ecological dynamics study on the water beetle family Scirtidae, which, although it is very abundant in benthic communities, is still poorly studied. The main objective of this study was to investigate the population aspects (composition, diversity, sex ratio) and ecological aspects (emergence patterns, seasonal dynamics and preferences for environmental factors) of the family Scirtidae over 15 years in Plitvice Lakes NP, Croatia. The study was conducted at three sites and in five different substrate types. A total of three taxa with different distributions were recorded in the study area: Hydrocyphon novaki and H. deflexicollis on the tufa barriers and the Elodes sp. in the spring area. The sex ratio was in favour of males in spring and early summer, while it shifted in favour of females towards the end of autumn. The abundance and emergence of the family were primarily determined by the environmental parameters which showed the greatest fluctuations over a period of 15 years: water temperature, water discharge and oxygen saturation. Our results clearly show that Scirtidae can be used as indicators of stream zonation and habitat quality. Based on the methodology and the results of this study, we conclude that Scirtidae should be used in future monitoring and protection measures in karst freshwater habitats in southeastern Europe.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    蚊子之后,蜱是动物和公共卫生关注的最重要的病原体媒介之一,但是,除非蚊子tick长期附着在宿主上,否则可以提供机会来分析它们在不同人畜共患病原体的传播和动态中的作用。鉴于他们对公共卫生的兴趣,重要的是要了解哪些因素会影响其在不同宿主中的发病率,并建立有效的监测计划以确定人畜共患病原体的传播和溢出风险。受益于庞大的鸟类学家志愿者网络,我们使用231种鸟类的620,609个个体的信息分析了与蜱的存在相关的生活史特征。鸟类系统发育,地域性和年份解释了蜱虫患病率的大量差异。非殖民地物种不在草原上繁殖,并且不在非繁殖季节中作为群居群体或孤立的个体(例如画眉,鹌鹑和雀科)的蜱患病率较高,根据对从野生鸟类收集的蜱的分析,它们似乎是人畜共患监测计划的良好候选者。Ringers低估了tick的患病率,但如果经过适当的培训以检测和收集不同的tick发展阶段,则可以将其视为公共和动物健康监测计划的tick信息的重要来源。
    After mosquitoes, ticks are among the most important vector of pathogens of concern for animal and public health, but unless mosquitoes ticks remain attached to their hosts for long time periods providing an opportunity to analyse their role in the dispersal and dynamics of different zoonotic pathogens. Given their interest in public health it is important to understand which factors affect their incidence in different hosts and to stablish effective surveillance programs to determine the risk of transmission and spill-over of zoonotic pathogens. Taking benefit of a large network of volunteer ornithologists, we analysed the life-history traits associated to the presence of ticks using information of 620,609 individuals of 231 avian species. Bird phylogeny, locality and year explained a large amount of variance in tick prevalence. Non-colonial species non breeding in grasslands and non-spending the non-breeding season as gregarious groups or isolated individuals (e.g. thrushes, quails and finches) had the higher prevalence of ticks and appear as good candidates for zoonosis surveillance programs based on the analyses of ticks collected from wild birds. Ringers underestimated tick prevalence but can be considered as an important source of information of ticks for public and animal health surveillance programs if properly trained for the detection and collection of the different tick development phases.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    本研究调查了ZnO和CuO纳米颗粒(NPs)对淡水微藻可能的毒性作用,在BG-11培养基中,在白光LED照明下,在环境相关的纳米颗粒浓度(lmg/L)和高浓度(lOmg/L)下,斜生栅藻35天。时间对介质稳定性的影响,纳米粒子,并研究了它们与藻类毒性的关系。透射电子显微镜显示由于存在纳米颗粒混合物(10mg/L),对藻类的结构破坏。含有纳米颗粒混合物的样品的FTIR(傅里叶变换红外)分析显示键的添加和峰位置及其强度值的差异。在10mg/LNP下在14天至21天之间观察到生物质的抑制时间。在1毫克/升,发现NPs对藻类的毒性顺序为:CuONPs(最高毒性)>ZnONPs>ZnOCuONPs(最小毒性)。在藻类细胞暴露于10mg/LNP浓度的NP混合物期间,与暴露于单个NP期间相比,观察到较小的金属沉积值。在两种浓度水平下观察到两种NP对藻类干细胞重量的拮抗毒性作用。需要进一步的工作来了解由于NPs与藻类混合而导致的毒性所涉及的步骤,以便可以管理和最大程度地减少藻类对NPs的环境暴露。
    The present study investigated the possible toxic effect of ZnO and CuO nanoparticles (NPs) on freshwater microalgae, Scenedesmus obliquus at environmentally- relevant nanoparticle concentration (1 mg/L) and high concentration (10 mg/L) in BG-11 medium under white light LED-illumination over 35 days. The effect of time on the stability of media, nanoparticles, and their relation to toxicity to algae was also studied. The transmission electron microscopy indicated structural damage to algae due to the presence of a mixture of nanoparticles (at 10 mg/L). FTIR (Fourier Transform infrared) analysis of a sample containing a mixture of nanoparticles showed an addition of bonds and a difference in the peak location and its intensity values. The inhibition time for biomass was observed between 14 days and 21 days at 10 mg/L NPs. At 1 mg/L, the order of toxicity of NPs to algae was found to be: CuO NPs (highest toxicity) > ZnO NPs>ZnO + CuO NPs (least toxicity). During exposure of algae cells to a mixture of NPs at 10 mg/L NP concentration, a smaller value of metal deposition was observed than that during exposure to individual NPs. Antagonistic toxic effects of two NPs on dry cell weight of algae was observed at both concentration levels. Future work is needed to understand the steps involved in toxicity due to mixture of NPs to algae so that environmental exposures of algae to NPs can be managed and minimized.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    集体行为可塑性允许蚁群适应不断变化的条件。红色收割蚂蚁(Pogonomyrmexbarbatus),一种吃沙漠种子的物种,调节对水分胁迫的觅食活动。觅食蚂蚁失去水分蒸发。在干燥条件下减少觅食活动会牺牲食物摄入量,但会节省水分。一年之内,有些菌落倾向于在干燥的日子里减少觅食,而另一些则没有。我们研究了群体之间在集体行为可塑性方面的这些差异是否每年都持续存在。殖民地与一个单一的女王一起生活了20-30年,女王产生了连续的工人群,这些工人只活了一年。所有菌落倾向于减少觅食的湿度水平每年都有所不同。在2016年至2021年的5年内,对95个殖民地的纵向观察表明,殖民地之间的差异,它们如何调节觅食活动以响应湿度的日常变化,坚持多年。大约40%的菌落持续减少觅食活动,年复一年,在每日最大相对湿度较低的日子里;大约20%的菌落从未这样做过,在干燥的日子里和潮湿的日子里一样多或更多的觅食。由于气候变化,殖民地之间的这种差异可能允许从干旱中进行进化救援。
    Collective behavioural plasticity allows ant colonies to adjust to changing conditions. The red harvester ant (Pogonomyrmex barbatus), a desert seed-eating species, regulates foraging activity in response to water stress. Foraging ants lose water to evaporation. Reducing foraging activity in dry conditions sacrifices food intake but conserves water. Within a year, some colonies tend to reduce foraging on dry days while others do not. We examined whether these differences among colonies in collective behavioural plasticity persist from year to year. Colonies live 20-30 years with a single queen who produces successive cohorts of workers which live only a year. The humidity level at which all colonies tend to reduce foraging varies from year to year. Longitudinal observations of 95 colonies over 5 years between 2016 and 2021 showed that differences among colonies, in how they regulate foraging activity in response to day-to-day changes in humidity, persist across years. Approximately 40% of colonies consistently reduced foraging activity, year after year, on days with low daily maximum relative humidity; approximately 20% of colonies never did, foraging as much or more on dry days as on humid days. This variation among colonies may allow evolutionary rescue from drought due to climate change.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Randomized Controlled Trial
    在年龄≥12岁的日本患者中,52周应用盐酸奥昔布宁20%洗剂(20%OL)治疗原发性手汗症(PPHH)的长期安全性和有效性在4周的开放标签扩展(OLE)中进行了评估,随机化,双盲(DB)研究。OLE包括114名完成DB研究并希望继续治疗的患者和12名新患者。在安全性分析人群(125名患者)中,不良事件(AE)和药物不良反应(ADR)的发生率分别为79.2%和36.0%,分别。在两名患者中观察到严重的AE,但认为与研究药物无关。导致研究中止的AE发生率为1.6%。应用场所不良事件和不良反应发生率分别为35.2%和26.4%,分别。大多数事件的严重程度为轻度。与口干相关的抗胆碱能AEs的发生率为口渴的3.2%,咽干的0.8%。20%OL的长期疗效通过持续减少汗液量和改善多汗症疾病严重程度量表和皮肤病生活质量指数得到证实。这项研究有几个局限性:首先,结果可能包括一些偏见,因为大多数参与者来自先前的DB研究;其次,结果可能无法推广,因为只有少数参与者处于最容易患PPHH的年龄组(即,<15岁);第三,这项研究没有从治疗中获得安全性信息超过52周,因此,这些信息必须在未来的临床实践中收集。在本研究中,在应用20%OL52周后,在PPHH患者中没有观察到降低的治疗效果。此外,少数患者出现严重AE或导致研究治疗中止的AE.
    The long-term safety and efficacy of 52-week application of oxybutynin hydrochloride 20% lotion (20% OL) for the treatment of primary palmar hyperhidrosis (PPHH) in Japanese patients aged ≥12 years were evaluated in an open-label extension (OLE) of a 4-week, randomized, double-blind (DB) study. The OLE included 114 patients who completed the DB study and wished to continue treatment and 12 new patients. In the safety analysis population (125 patients), the incidence of adverse events (AEs) and adverse drug reactions (ADRs) was 79.2% and 36.0%, respectively. Serious AEs were observed in two patients but were considered unrelated to the investigational drug. The incidence of AEs that led to study discontinuation was 1.6%. The incidence of application site AEs and ADRs was 35.2% and 26.4%, respectively. The severity of most events was mild. The incidence of anticholinergic AEs related to dry mouth was 3.2% for thirst and 0.8% for dry throat. The long-term efficacy of 20% OL was confirmed by a long-lasting reduction in sweat volume and improvement in the Hyperhidrosis Disease Severity Scale and Dermatology Life Quality Index. This study has several limitations: First the results may include some bias because most of the participants were from the prior DB study; second, the results may not be generalizable because only a few participants were in the age group most susceptible to PPHH (i.e., < 15 years old); and third, the study did not obtain safety information from treatment for more than 52 weeks, so this information must be collected in clinical practice in the future. No reduced therapeutic effect was observed in patients with PPHH in this study after 52-week application of 20% OL. Also, few patients experienced serious AEs or AEs that led to study treatment discontinuation.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    胃肠道线虫(GIN)寄生虫在许多动物种群的生态动态中起着重要作用。最近的研究表明,GIN感染动力学的精细尺度空间变化在野生动物系统中很重要,但是这种变化背后的环境驱动因素仍然知之甚少。我们使用了超过二十年的GIN寄生虫卵数数据,主机空间使用,和来自圣基尔达Soay绵羊长期研究的空间植被数据,以测试个人家庭范围内的空间自相关和植被如何预测三个年龄组的寄生虫负担。我们开发了一种新方法来量化家庭范围内存在的植物功能性状,以描述存在的植被质量。植被和空间的影响因年龄组而异。在未成熟的羔羊中,strongyle寄生虫粪便卵数(FEC)是空间结构的,在我们研究区域的北部和南部最高。与宿主体重和空间自相关无关,植物功能性状预测寄生虫卵数。较高的卵数与更易消化和首选的植物功能性状相关,表明这种关联可能是由寄主密度和栖息地偏好驱动的。相比之下,我们没有发现任何证据表明寄生虫FEC与一岁或成年绵羊寄主家庭范围内的植物功能性状有关。成人FEC是空间结构的,在我们研究区域的东北部负担最大,而一岁的FEC没有显示空间结构的证据。未成熟个体中的寄生虫负担似乎更容易受到环境中精细尺度空间变化的影响,强调这种异质性对我们理解野生动物流行病学和健康的重要性。我们的发现支持了精细尺度的环境变化对野生动植物疾病生态学的重要性,并提供了新的证据表明,这种影响可能因人口群体而异。
    Gastrointestinal nematode (GIN) parasites play an important role in the ecological dynamics of many animal populations. Recent studies suggest that fine-scale spatial variation in GIN infection dynamics is important in wildlife systems, but the environmental drivers underlying this variation remain poorly understood. We used data from over two decades of GIN parasite egg counts, host space use, and spatial vegetation data from a long-term study of Soay sheep on St Kilda to test how spatial autocorrelation and vegetation in an individual\'s home range predict parasite burden across three age groups. We developed a novel approach to quantify the plant functional traits present in a home range to describe the quality of vegetation present. Effects of vegetation and space varied between age classes. In immature lambs, strongyle parasite faecal egg counts (FEC) were spatially structured, being highest in the north and south of our study area. Independent of host body weight and spatial autocorrelation, plant functional traits predicted parasite egg counts. Higher egg counts were associated with more digestible and preferred plant functional traits, suggesting the association could be driven by host density and habitat preference. In contrast, we found no evidence that parasite FEC were related to plant functional traits in the host home range in yearlings or adult sheep. Adult FEC were spatially structured, with highest burdens in the north-east of our study area, while yearling FEC showed no evidence of spatial structuring. Parasite burdens in immature individuals appear more readily influenced by fine-scale spatial variation in the environment, highlighting the importance of such heterogeneity for our understanding of wildlife epidemiology and health. Our findings support the importance of fine-scale environmental variation for wildlife disease ecology and provides new evidence that such effects may vary across demographic groups within a population.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    动物使用与气候相关的环境线索来调整繁殖时间和投资,以适应最高的食物供应。在鸟类中,春季温度是通常记录的用于开始繁殖的线索,但是随着全球气候变化,生物体正在经历环境温度的方向性变化和极端的逐年降水波动。Montane环境表现出复杂的气候模式,其中温度和降水沿海拔梯度变化,降水量的年变化加剧,导致大雪和干旱之间的剧烈波动。我们使用了10年的数据来研究气候条件的年度变化如何与内华达山脉北部两个海拔的常住山雀(Poecilegambeli)的繁殖物候和繁殖性能差异有关,美国。春季温度的变化与我们系统中各个海拔的繁殖物候差异无关。更大的积雪与稍后的繁殖开始有关,但不低,海拔。在干旱下,育苗的大小减少了,但只能在低海拔地区。我们的数据表明气候与鸟类繁殖之间的复杂关系,并指出秋季气候对繁殖性能很重要,可能是通过其对无脊椎动物物候和丰度的影响。
    Animals use climate-related environmental cues to fine-tune breeding timing and investment to match peak food availability. In birds, spring temperature is a commonly documented cue used to initiate breeding, but with global climate change, organisms are experiencing both directional changes in ambient temperatures and extreme year-to-year precipitation fluctuations. Montane environments exhibit complex climate patterns where temperatures and precipitation change along elevational gradients, and where exacerbated annual variation in precipitation has resulted in extreme swings between heavy snow and drought. We used 10 years of data to investigate how annual variation in climatic conditions is associated with differences in breeding phenology and reproductive performance in resident mountain chickadees (Poecile gambeli) at two elevations in the northern Sierra Nevada mountains, USA. Variation in spring temperature was not associated with differences in breeding phenology across elevations in our system. Greater snow accumulation was associated with later breeding initiation at high, but not low, elevation. Brood size was reduced under drought, but only at low elevation. Our data suggest complex relationships between climate and avian reproduction and point to autumn climate as important for reproductive performance, likely via its effect on phenology and abundance of invertebrates.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    有相当多的证据表明,当地自然适应,然而,关于其遗传基础的重要问题仍然存在。涉及多少个基因座?它们的效应大小是多少?条件中性与遗传权衡的相对重要性是什么?这里我们在自花授粉中解决这些问题,一年生植物拟南芥。我们使用了来自意大利和瑞典两个当地适应种群的400个重组自交系(RIL),在父母所在地种植RIL和父母,并绘制了定量性状基因座(QTL)的平均适合度(种植的果实/幼苗)。我们之前发表了研究前3年的结果,再加上五年,提供了一个独特的机会来评估选择的时间变化如何影响QTL检测和分类。我们在意大利发现了10个适应性QTL和一个适应不良QTL,瑞典有6个适应性QTL和4个适应不良QTL。在这两个位点都发现了适应不良的QTL,这表明即使是局部适应的种群也不总是处于其基因型最佳状态。自适应QTL的平均效应大小,0.97和0.55水果在意大利和瑞典,分别,相对于RIL的平均适合度(在两个地点种植约8个果实/幼苗)。遗传权衡(4例)和条件中立(7例)都有助于该系统的局部适应。与我们之前的3年研究相比,8年的数据集提供了更大的能力来检测QTL和估计其位置。确定一个新的遗传权衡,并将一个遗传权衡解决为两个条件适应性QTL。
    There is considerable evidence for local adaptation in nature, yet important questions remain regarding its genetic basis. How many loci are involved? What are their effect sizes? What is the relative importance of conditional neutrality versus genetic trade-offs? Here we address these questions in the self-pollinating, annual plant Arabidopsis thaliana. We used 400 recombinant inbred lines (RILs) derived from two locally adapted populations in Italy and Sweden, grew the RILs and parents at the parental locations, and mapped quantitative trait loci (QTL) for mean fitness (fruits/seedling planted). We previously published results from the first 3 years of the study, and here add five additional years, providing a unique opportunity to assess how temporal variation in selection might affect QTL detection and classification. We found 10 adaptive and one maladaptive QTL in Italy, and six adaptive and four maladaptive QTL in Sweden. The discovery of maladaptive QTL at both sites suggests that even locally adapted populations are not always at their genotypic optimum. Mean effect sizes for adaptive QTL, 0.97 and 0.55 fruits in Italy and Sweden, respectively, were large relative to the mean fitness of the RILs (approximately 8 fruits/seedling planted at both sites). Both genetic trade-offs (four cases) and conditional neutrality (seven cases) contribute to local adaptation in this system. The 8-year dataset provided greater power to detect QTL and to estimate their locations compared to our previous 3-year study, identifying one new genetic trade-off and resolving one genetic trade-off into two conditionally adaptive QTL.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    本报告介绍了用钢帘线加固的混凝土梁的长期测试结果。在这项研究中,天然骨料完全被废砂或陶瓷产品和陶瓷空心砖生产中的废物取代。根据参考混凝土的指南确定所使用的各个部分的量。总共测试了八种混合物;这些混合物在使用的废物骨料类型方面有所不同。为每种混合物制造具有各种纤维增强比的元件。钢纤维和废纤维的用量为0.0%,0.5%,和1.0%。实验确定每种混合物的抗压强度和弹性模量。主要测试是四点梁弯曲测试。在支架上测试尺寸为100mm×200mm×2900mm的光束,这是专门准备的,以便可以同时测试三个光束。纤维增强率为0.5%和1.0%。进行了1000天的长期研究。在测试期间,测量了梁的挠度和裂纹。将获得的结果与使用几种方法计算的值进行比较,考虑到分散钢筋的影响。结果使计算具有不同类型废料的混合物的单个值的最佳方法得以确定。
    This report presents the results of long-term tests on concrete beams reinforced with steel cord. In this study, natural aggregate was wholly replaced with waste sand or with wastes from the production of ceramic products and ceramic hollow bricks. The amounts of individual fractions used were determined in accordance with guidelines for reference concrete. A total of eight mixtures were tested; these differed in terms of the type of waste aggregate used. Elements with various fiber-reinforcement ratios were made for each mixture. Steel fibers and waste fibers were used in amounts of 0.0%, 0.5%, and 1.0%. Compressive strength and modulus of elasticity were determined experimentally for each mixture. The main test was a four-point beam bending test. Beams with dimensions of 100 mm × 200 mm × 2900 mm were tested on a stand, which was specially prepared so that three beams could be tested simultaneously. Fiber-reinforcement ratios were 0.5% and 1.0%. Long-term studies were conducted for 1000 days. During the testing period, beam deflections and cracks were measured. The obtained results were compared with values calculated using several methods, considering the influence of dispersed reinforcement. The results enabled the best methods for calculating individual values for mixtures with different types of waste materials to be determined.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

公众号