trimming

修整
  • 文章类型: Journal Article
    大麻花序由于其独特的植物化学物质,例如大麻素和萜烯,在医学领域被广泛用于治疗各种症状和疾病。常见的大麻花序采后程序包括修剪,然后干燥,固化,以及随后的存储。采后修剪步骤,特别是它的时间(干燥前或干燥后)和修剪的程度,就其对大麻素和萜烯含量的影响而言,没有得到最佳的精炼。在这项研究中,我们的目标是确定商业上可用的药用大麻杂种化学疗法的最佳修剪条件,以最大化其大麻素和萜烯含量为目标。
    要做到这一点,我们调查了干燥前修剪与干燥后修剪的影响,并使用液相和气相色谱法评估了干燥前轻度修剪与侵袭性修剪对大麻素和萜烯谱的影响.
    我们的结果表明,预干燥温和修剪产生最高的大麻素浓度,可能是由于胁迫信号和从糖叶到花序的前体流入之间的最佳平衡。另一方面,干燥后修剪产生最高的萜烯含量。
    确定使大麻中大麻素和萜烯含量最大化的最佳修剪条件具有挑战性。因此,种植者在修剪实践中面临一个决定:优先考虑提高大麻素含量或增加芳香萜烯浓度,因为同时对两者进行优化似乎很困难。
    UNASSIGNED: Cannabis sativa L. inflorescences are widely used in the medicinal field as treatments for a variety of symptoms and illnesses due to their unique phytochemicals such as cannabinoids and terpenes. Common postharvest procedures for cannabis inflorescence include trimming, followed by drying, curing, and subsequent storage. The postharvest trimming step, particularly its timing (pre- or post-drying) and the extent of trimming, is not optimally refined in terms of its impact on the cannabinoid and terpene content. In this study, our objective was to identify the optimal trimming conditions for a commercially available medicinal cannabis hybrid chemovar, with the goal of maximizing its cannabinoid and terpene content.
    UNASSIGNED: To achieve this, we investigated the effects of pre- versus post-drying trimming and evaluated the impact of mild versus aggressive trimming prior to drying on the cannabinoid and terpene profiles using liquid and gas chromatography.
    UNASSIGNED: Our results indicated that pre-drying mild trimming yielded the highest cannabinoid concentration, possibly due to optimal balance between stress signals and precursor influx from the sugar leaves to the inflorescence. On the other, post-drying trimming yielded the highest terpene content.
    UNASSIGNED: Identifying the optimal trimming conditions that maximize both cannabinoid and terpene levels in cannabis is challenging. Therefore, growers face a decision in their trimming practices: to prioritize either enhanced cannabinoid content or increased aromatic terpene concentrations, as optimizing for both simultaneously appears to be difficult.
    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
    磨料水射流加工工艺是在20世纪80年代作为一种新的切削工具引入的;该工艺几乎能够切割任何材料。目前,AWJ工艺在许多世界级工厂中使用,生产用于日常生活的零件。本文首先对这一过程及其影响参数进行了描述,以及AWJ工具本身以及射流-材料相互作用的过程模型。AWJ材料去除过程是通过磨料颗粒的高速冲击而发生的,其尖端在微观尺度上对材料进行微加工,没有热或机械的不利影响。切割表面的宏观特征,比如它的锥度,trackback,和波纹,讨论,以及使用这些属性提高切削零件几何精度的方法。例如,动态角度补偿用于校正形状切割中的锥度和底切。表面光洁度由切削速度控制,液压,和磨料参数使用软件和过程模型内置到数控机床的控制器。除了形状切割,提出了边缘修剪,专注于飞机和汽车结构中使用的碳纤维复合材料,使用特殊AWJ工具和操纵器的地方。讨论了微电子和太阳能电池零件的精密切割示例,以描述所使用的特殊技术,如机器视觉和真空辅助,这已被发现是必不可少的完整性和准确性的切割零件。AWJ加工过程的使用扩展到其他应用,比如钻孔,无聊,铣削,转动,和表面改性,这些都是本文提出的实际工业应用。为了证明AWJ加工过程的多功能性,本文选择的数据涵盖了广泛的材料,如金属,玻璃,复合材料,和陶瓷,以及广泛的厚度,从1毫米到600毫米。工业4.0和5.0的趋势,AI,和物联网也被介绍。
    The abrasive waterjet machining process was introduced in the 1980s as a new cutting tool; the process has the ability to cut almost any material. Currently, the AWJ process is used in many world-class factories, producing parts for use in daily life. A description of this process and its influencing parameters are first presented in this paper, along with process models for the AWJ tool itself and also for the jet-material interaction. The AWJ material removal process occurs through the high-velocity impact of abrasive particles, whose tips micromachine the material at the microscopic scale, with no thermal or mechanical adverse effects. The macro-characteristics of the cut surface, such as its taper, trailback, and waviness, are discussed, along with methods of improving the geometrical accuracy of the cut parts using these attributes. For example, dynamic angular compensation is used to correct for the taper and undercut in shape cutting. The surface finish is controlled by the cutting speed, hydraulic, and abrasive parameters using software and process models built into the controllers of CNC machines. In addition to shape cutting, edge trimming is presented, with a focus on the carbon fiber composites used in aircraft and automotive structures, where special AWJ tools and manipulators are used. Examples of the precision cutting of microelectronic and solar cell parts are discussed to describe the special techniques that are used, such as machine vision and vacuum-assist, which have been found to be essential to the integrity and accuracy of cut parts. The use of the AWJ machining process was extended to other applications, such as drilling, boring, milling, turning, and surface modification, which are presented in this paper as actual industrial applications. To demonstrate the versatility of the AWJ machining process, the data in this paper were selected to cover a wide range of materials, such as metal, glass, composites, and ceramics, and also a wide range of thicknesses, from 1 mm to 600 mm. The trends of Industry 4.0 and 5.0, AI, and IoT are also presented.
    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
    系统发育分析已进入基因组学(多位点)时代。对于经验不足的研究人员来说,征服基于多位点的系统发育重建所需的大量软件程序可能有些令人生畏且耗时。PhyloSuite,具有用户友好GUI的软件,旨在通过整合多位点和单基因系统发育所需的多个软件程序,并进一步简化整个过程,从而使这一过程更易于访问。在这个协议中,我们的目的是解释如何在PhyloSuite中进行系统发育管道和基于树的分析的每个步骤。我们还提出了一个新版本的PhyloSuite(v1.2.3),其中我们修复了一些错误,做了一些优化,并引入了一些新功能,包括一些基于树的分析,如信噪比计算,饱和度分析,虚假物种鉴定,等。分步协议包括背景信息(即,步骤做什么),原因(即,为什么要执行步骤),和操作(即,如何做到这一点)。该协议将帮助研究人员快速启动他们的方式通过多位点系统发育分析,尤其是那些有兴趣进行基于细胞器的分析。
    Phylogenetic analysis has entered the genomics (multilocus) era. For less experienced researchers, conquering the large number of software programs required for a multilocus-based phylogenetic reconstruction can be somewhat daunting and time-consuming. PhyloSuite, a software with a user-friendly GUI, was designed to make this process more accessible by integrating multiple software programs needed for multilocus and single-gene phylogenies and further streamlining the whole process. In this protocol, we aim to explain how to conduct each step of the phylogenetic pipeline and tree-based analyses in PhyloSuite. We also present a new version of PhyloSuite (v1.2.3), wherein we fixed some bugs, made some optimizations, and introduced some new functions, including a number of tree-based analyses, such as signal-to-noise calculation, saturation analysis, spurious species identification, and etc. The step-by-step protocol includes background information (i.e., what the step does), reasons (i.e., why do the step), and operations (i.e., how to do it). This protocol will help researchers quick-start their way through the multilocus phylogenetic analysis, especially those interested in conducting organelle-based analyses.
    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
    相关光电子显微镜(CLEM)涵盖了广泛的实验方法,具有不同程度的复杂性和技术挑战,其中光和电子显微镜的属性结合在一个实验中。尽管生物学问题总是决定什么技术是最合适的,我们通常着手应用最简单的工作流程。对于表达荧光标记的分子的2D细胞培养物,我们报告了一个简单和非常强大的CLEM方法,通过使用网格取景器成像盘。我们首先使用光学显微镜确定荧光的总体定位,然后通过将荧光投影到透射电子显微镜(TEM)获得的超微结构参考空间上来追溯荧光的起源/定位。在这里,我们描述了这个工作流程,并强调了这样一个简单的CLEM实验的样品制备的一些基本原理。我们将特别关注用于TEM的树脂嵌入和在电子显微镜中引入样品之后的步骤。
    Correlative Light Electron Microscopy (CLEM) encompasses a wide range of experimental approaches with different degrees of complexity and technical challenges where the attributes of both light and electron microscopy are combined in a single experiment. Although the biological question always determines what technology is the most appropriate, we generally set out to apply the simplest workflow possible. For 2D cell cultures expressing fluorescently tagged molecules, we report on a simple and very powerful CLEM approach by using gridded finder imaging dishes. We first determine the gross localization of the fluorescence using light microscopy and subsequently we retrace the origin/localization of the fluorescence by projecting it onto the ultrastructural reference space obtained by transmission electron microscopy (TEM). Here we describe this workflow and highlight some basic principles of the sample preparation for such a simple CLEM experiment. We will specifically focus on the steps following the resin embedding for TEM and the introduction of the sample in the electron microscope.
    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
    分枝/分枝模式在确定草的结构和多样性中起着重要作用,并且发现修剪会导致草坪草的分till。最近,据报道,过氧化氢(H2O2)调节腋芽的发育。然而,H2O2在百慕大草修剪诱导分枝中的作用,一种草皮草,尚不清楚。我们的研究揭示了修剪对促进茎节分茎芽发芽和生长的重要影响,随着主茎中分茎数量的增加。这种效应伴随着细胞分裂素和蔗糖含量的时空变化,以及相关基因在腋芽中的表达。此外,部分修剪新生分till会导致其叶片中蔗糖和淀粉储备的增加,这可以归因于光合作用能力的增强。重要的是,修剪可促进新生分till和腋生stolon芽的叶子中的H2O2快速爆发。此外,外源施用H2O2通过影响细胞分裂素相关基因的表达,显著增加修剪后的分ill数,增强光合作用潜力,能量储备和抗氧化酶活性。一起来看,这些结果表明,内源生产和外源添加H2O2都增强了修剪对百慕大分枝过程的诱导作用,从而帮助增加能量供应和维持氧化还原状态在新形成的分till。
    Tillering/branching pattern plays a significant role in determining the structure and diversity of grass, and trimming has been found to induce tillering in turfgrass. Recently, it has been reported that hydrogen peroxide (H2O2) regulates axillary bud development. However, the role of H2O2 in trimming-induced tillering in bermudagrass, a kind of turfgrass, remains unclear. Our study unveils the significant impact of trimming on promoting the sprouting and growth of tiller buds in stolon nodes, along with an increase in the number of tillers in the main stem. This effect is accompanied by spatial-temporal changes in cytokinin and sucrose content, as well as relevant gene expression in axillary buds. In addition, the partial trimming of new-born tillers results in an increase in sucrose and starch reserves in their leaves, which can be attributed to the enhanced photosynthesis capacity. Importantly, trimming promotes a rapid H2O2 burst in the leaves of new-born tillers and axillary stolon buds. Furthermore, exogenous application of H2O2 significantly increases the number of tillers after trimming by affecting the expression of cytokinin-related genes, bolstering photosynthesis potential, energy reserves and antioxidant enzyme activity. Taken together, these results indicate that both endogenous production and exogenous addition of H2O2 enhance the inductive effects of trimming on the tillering process in bermudagrass, thus helping boost energy supply and maintain the redox state in newly formed tillers.
    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
    背景:跛行与全世界奶牛群的动物福利受损和生产力下降有关。然而,对埃及奶牛水牛中爪病变的患病率知之甚少。此外,水牛爪子修剪的最佳测量是未知的。进行了横断面尸体研究,其中从4个屠宰场收集了135对水牛后足,并检查了爪病变的存在。计算每种类型病变的比例和相关的95%置信区间(CI)。一组单独的健康爪子(n=26)接受了超声检查(US)和计算机断层扫描(CT)。使用Passing-Bablok回归和组内相关系数评估US和CT测量之间的一致性。CT测量用于计算修剪建议。
    结果:在242个爪中至少发现了一个病变(89.6%,95%CI=85.4-93.0)。在健康的爪子里,在US和CT测量结果之间发现了差到中度的一致性,这可能是由于研究的样本量所致.小母牛外侧和内侧爪的平均±标准偏差(SD)最小推荐外壁长度为7.1±0.36cm和7.5±0.35cm,分别。5岁以上水牛的平均±SD最小推荐外壁长度为8.2±0.27cm,外侧和内侧爪为8.4±0.39cm,分别。
    结论:该研究发现埃及水牛的爪病变患病率很高,其临床意义需要进一步阐明。推荐的测量将有助于指导水牛的爪子修剪,以最大程度地减少病变。
    BACKGROUND: Lameness has been associated with compromised animal welfare and reduced productivity in dairy cattle herds worldwide. However, little is known about the prevalence of claw lesions in the dairy buffalo population in Egypt. Furthermore, the optimum measurements for claw trimming in buffalo are unknown. A cross-sectional cadaver study was conducted where 135 pair buffalo hind feet were collected from 4 slaughterhouses and examined for the presence of claw lesions. The proportion and associated 95% confidence interval (CI) of each type of lesion were calculated. A separate set of healthy claws (n = 26) underwent ultrasonography (US) and computed tomography (CT). The agreement between US and CT measurements was assessed using Passing-Bablok regression and intraclass correlation coefficient. The CT measurements were used to calculate trimming recommendations.
    RESULTS: At least one lesion was identified in 242 claws (89.6%, 95% CI = 85.4-93.0). In healthy claws, poor to moderate agreement was identified between US and CT measurements which could be due a sample size of the study. The average ± standard deviation (SD) minimum recommended external wall length of the lateral and medial claws in heifers was 7.1 ± 0.36 cm and 7.5 ± 0.35 cm, respectively. The average ± SD minimum recommended external wall length in buffaloes over five years of age was 8.2 ± 0.27 cm and 8.4 ± 0.39 cm for the lateral and medial claws, respectively.
    CONCLUSIONS: The study found a high prevalence of claw lesions in buffalo in Egypt, the clinical significance of which requires further elucidation. Recommended measurements will help guide claw trimming in buffalo to minimise lesions.
    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
    这项研究的第一个目的是计算在三年的研究期间,瑞士奶牛群和牛犊手术中数字疼痛病变(“警报”病变;AL)的患病率。计算中包括以下AL:数字皮炎的M2期(DDM2),溃疡(U),中度和高度白线裂缝(WLF),白线脓肿(WLA),叉指型phlegmon(IP)和冠状和/或灯泡(SW)肿胀。在2020年2月至2023年2月之间,在参加国家爪子健康计划的瑞士养牛场中,由40名经过特殊培训的蹄修剪机以电子方式记录了手指疾病。使用的数据集包括来自702群的近25,000头母牛的35,000多次观察。在群体层面,2022年记录的主要AL是美国,占50.3%,其次是WLF,占38.1%,在牛一级,2022年,DDM2为5.4%,其次是美国3.7%。在学习期间,在2020年,ALs的群体内患病率从0.0%到最高66.1%。这项研究的第二个目的是确定与数字皮炎(DD)相关的牛群和牛水平的危险因素,使用2022年的数据,奶牛的U和白线病(WL)。而对于DD,分析的群体水平因素似乎对其发生的可能性有更大的影响,U和WL的存在主要与分析的牛水平因素相关。DD的风险随着群体修剪频率的增加而增加。与在松散的住房系统中饲养的牛群相比,在领带摊位中饲养的牛群对DD和WL的风险较低,而对U的风险较高。与其他品种的牛群和母牛相比,以荷斯坦弗利西亚牛为主的牛群发生DD的风险更高。随着奇偶校验的增加,奶牛患U和WL的风险较高,而对于DD,均等与患病率呈负相关.在放牧期间修剪的母牛比在住房期间修剪的母牛具有更高的U和WL风险。这些发现可能有助于改善影响结构与当前研究中评估的结构相似的农场中手指健康的管理措施,例如经常进入牧场的小群。有必要进行进一步的研究,以证明解决当前结果的措施与个体牛群风险评估的措施如何有助于改善各自牛群的健康。
    The first aim of this study was to calculate the prevalence of painful lesions of the digits (\"alarm\" lesions; ALs) in Swiss dairy herds and cow-calf operations over a three-year study period. The following ALs were included in the calculation: the M2 stage of digital dermatitis (DD M2), ulcers (U), white line fissures (WLF) of moderate and high severity, white line abscesses (WLA), interdigital phlegmon (IP) and swelling of the coronet and/or bulb (SW). Between February 2020 and February 2023, digit disorders were electronically recorded during routine trimmings by 40 specially trained hoof trimmers on Swiss cattle farms participating in the national claw health programme. The data set used consisted of over 35,000 observations from almost 25,000 cows from 702 herds. While at the herd-level, the predominant AL documented in 2022 was U with 50.3% followed by WLF with 38.1%, at the cow-level, in 2022, it was DD M2 with 5.4% followed by U with 3.7%. During the study period, within-herd prevalences of ALs ranged from 0.0% to a maximum of 66.1% in 2020. The second aim of this study was to determine herd- and cow-level risk factors associated with digital dermatitis (DD), U and white line disease (WL) in dairy cows using data from 2022. While for DD, analysed herd-level factors appeared to have a greater effect on the probability of its occurrence, the presence of U and WL was mainly associated with the analysed cow-level factors. The risk for DD increased with a higher herd trimming frequency. Herds kept in tie stalls had a lower risk for DD and WL and a higher risk for U compared to herds kept in loose housing systems. Herds with predominantly Holstein Friesian cows as well as Holstein Friesian cows had a higher risk for the occurrence of DD compared to herds and cows of other breeds. With increasing parity, cows had a higher risk of developing U and WL, whereas for DD, parity was negatively associated with prevalence. Cows trimmed during the grazing period had a higher risk of U and WL than cows trimmed during the housing period. These findings may contribute to improve management measures affecting the health of the digits in farms with structures similar to those evaluated in the current study, such as small herds with frequent access to pasture. Further research is warranted to demonstrate how measures addressing the current results combined with those of individual herd risk assessments might contribute to an improvement in the health of the digits in the respective dairy herds.
    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
    背景:高尿酸血症可导致腕关节滑膜增生。在严重的情况下,它可以导致痛风石沉积在腕管中,导致腕管压力增加和正中神经受压,导致腕管综合征(CTS),这被称为痛风性腕管综合征(GCTS)。至于痛风性腕管综合征的外科治疗,对于是否需要切除屈浅腱,学者们有不同的看法。目的比较修剪和切除病变浅屈肌腱治疗痛风性腕管综合征的临床疗效。
    方法:从2016年5月至2021年7月收集了10例诊断为痛风性腕管综合征的患者(13例受影响的腕关节)的临床数据,并根据手术方式分为两组:痛风侵蚀的浅表指腱的患病部分在9个腕部进行了修剪,4只手腕切除患病的浅表指屈肌腱。与屈曲和伸展功能相关的值,2-PD,DASH,BCTQ,比较两组患者手术前后的VAS评分及患指复发情况。
    结果:所有患肢都清除了痛风性结石,手指麻木改善,没有发生皮肤坏死,所有切口均在I期愈合,随访(13.58±5.53个月),屈伸功能组间无显著差异,2-PD,DASH,BCTQ,和VAS相对于受影响的手指,两组患者手术前后均有明显改善。仅一个腕关节的治疗包括修剪以去除肌腱的病变部位,手术后1年再次出现,并且在两种手术中都有一例从较大的梨状肌萎缩中恢复不良。
    结论:关于痛风性腕管综合征患者的手术治疗,其中痛风性结石已侵入手指的浅屈肌腱,可以选择性地切除患病的浅屈肌腱,并且受影响的手指的术后活动性可能不会受到损害。
    BACKGROUND: Hyperuricemia can lead to synovial hyperplasia in the wrist. In severe cases, it can lead to the deposition of gouty stone in the carpal tunnel, resulting in increased pressure in the carpal tunnel and compression of the median nerve to cause carpal tunnel syndrome (CTS), which is called gouty carpal tunnel syndrome (GCTS). As for the surgical treatment of gouty carpal tunnel syndrome, scholars have different opinions on whether it is necessary to remove the superficial flexor tendon. The purpose of this study was to compare the clinical efficacy of trimming and resection of the diseased superficial flexor tendon in the treatment of gouty carpal tunnel syndrome.
    METHODS: Clinical data were collected from May 2016 to July 2021 from 10 patients (13 affected wrists) diagnosed with gouty carpal tunnel syndrome and classified into two groups according to the surgical modality: the diseased portion of the gout-eroded superficial finger tendon was trimmed in 9 wrists, and the diseased superficial finger flexor tendon was excised in 4 wrists. Values related to flexion and extension functions, 2-PD, DASH, BCTQ, VAS and recurrence in the affected fingers were compared between the two groups as well as before and after surgery in each group.
    RESULTS: All affected limbs used were cleared of gouty stones, finger numbness improved, no skin necrosis occurred, and all incisions healed at stage I. At follow-up (13.58 ± 5.53 months), there was no significant difference between groups in flexion and extension function, 2-PD, DASH, BCTQ, and VAS with respect to the affected fingers, and patients in both groups improved significantly before and after surgery. Treatment of only one wrist involved trimming to remove lesion-affected portions of tendon, which reappeared 1 year after surgery, and there was one case of poor recovery from greater piriformis muscle atrophy in both procedures.
    CONCLUSIONS: Regarding surgical treatment of patients with gouty carpal tunnel syndrome in which the gouty stone has invaded the superficial flexor tendons of the fingers, the diseased superficial flexor tendons can be selectively excised, and the postoperative mobility of the affected fingers may not be impaired.
    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
    倾向评分(PS)加权方法通常用于调整观察性治疗比较中的混杂因素。然而,在实质性协变量失衡的背景下,PS值可能接近0和1,从而产生估计的治疗效果的极端权重和膨胀方差。适应标准逆概率治疗权重(IPTW)可以减少极端的影响,包括排除PS值接近0或1的人的修剪方法。或者,重叠加权(OW)优化与偏差和方差相关的标准,并且与其他PS加权和匹配方法相比表现良好。然而,尚未与倾向评分分层(PSS)进行比较.PSS具有一些相同的潜在优势;不敏感的极端值。我们试图在实质性协变量失衡的情况下比较这些方法,以产生实用的建议。
    使用分析推导来建立方法之间的联系,并进行了模拟研究,以评估替代方法的偏差和方差。
    我们发现OW总体上是优越的,特别是随着协变量失衡的增加。此外,一种基于Mantel-Haenszel权重(PSS-MH)实现PSS的通用方法相当于OW的粗化版本,并且几乎可以执行。最后,修整方法增加了方法之间的偏差(IPTW,PSS和PSS-MH),除非PS模型重新拟合到修剪后的样本,并且重新推导权重或地层。在重新装配的修剪之后,所有方法的执行类似于OW。
    这些结果可以指导选择,具有实质性协变量失衡的观察性研究的PS方法的实施和报告。
    UNASSIGNED: Propensity score (PS) weighting methods are commonly used to adjust for confounding in observational treatment comparisons. However, in the setting of substantial covariate imbalance, PS values may approach 0 and 1, yielding extreme weights and inflated variance of the estimated treatment effect. Adaptations of the standard inverse probability of treatment weights (IPTW) can reduce the influence of extremes, including trimming methods that exclude people with PS values near 0 or 1. Alternatively, overlap weighting (OW) optimizes criteria related to bias and variance, and performs well compared to other PS weighting and matching methods. However, it has not been compared to propensity score stratification (PSS). PSS has some of the same potential advantages; being insensitive extreme values. We sought to compare these methods in the setting of substantial covariate imbalance to generate practical recommendations.
    UNASSIGNED: Analytical derivations were used to establish connections between methods, and simulation studies were conducted to assess bias and variance of alternative methods.
    UNASSIGNED: We find that OW is generally superior, particularly as covariate imbalance increases. In addition, a common method for implementing PSS based on Mantel-Haenszel weights (PSS-MH) is equivalent to a coarsened version of OW and can perform nearly as well. Finally, trimming methods increase bias across methods (IPTW, PSS and PSS-MH) unless the PS model is re-fit to the trimmed sample and weights or strata are re-derived. After trimming with re-fitting, all methods perform similarly to OW.
    UNASSIGNED: These results may guide the selection, implementation and reporting of PS methods for observational studies with substantial covariate imbalance.
    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
    重要的是要了解蹄修剪对蹄和肢体构象的影响,以最大限度地提高其对马的阑尾骨骼健康的益处,从而促进运动马的运动表现和运动寿命的改善。关于蹄修剪后胸肢体关节角度的可能变化以及胸肢体关节角度与蹄测量之间的相关性的信息很少。为此,十九只Mangalarga母马接受了例行的蹄部修剪。在手术之前和之后进行视觉记录(照片)。差异(p<0.05)发现蹄长,前束角,后跟角,鞋跟内侧高度,和掌指角。修剪前,青蛙的长度与肩周角(SH)之间存在相关性(r=-0.457;p=0.049),脚趾长度和肩地角(SG)之间(r=-0.553;p=0.049)。从青蛙到侧壁的距离与SH角之间也存在相关性(r=0.690;p=0.001)。修整后,肱骨放射(HR)和SH关节角度之间存在相关性(r=0.669;p=0.002),以及SG和SH角(r=0.488;p=0.034)。这项研究表明,修剪对脚趾角和脚跟角以及掌指关节角的直接影响,除了蹄和近端关节角度之间的相关性,修剪后,因此证明修剪的相关性不仅在蹄形态上,而且在马的附肢骨骼的构造中。
    It is important to understand the effects of hoof trimming on hoof and limb conformation to maximize its benefits on the health of the appendicular skeleton of horses, thus promoting improvements in athletic performance and sporting longevity with regard to athletic horses. There is little information on possible changes in the angulation of the thoracic limb joints after hoof trimming and correlations between the angulation of the thoracic limb joints with hoof measurements. To that purpose, nineteen Mangalarga mares received routine hoof trimming. Visual recordings (photographs) were taken before and after the procedure. Differences (p < 0.05) were found in hoof length, toe angle, heel angle, medial heel height, and metacarpophalangeal angle. Before trimming, correlations were found between frog length and scapulohumeral angle (SH) (r = -0.457; p = 0.049), and between toe length and shoulder-ground angle (SG) (r = -0.553; p = 0.049). A correlation was also seen between the distance from the frog to the lateral wall and the SH angle (r = 0.690; p = 0.001). After trimming, there was a correlation between humeroradial (HR) and SH joint angles (r = 0.669; p = 0.002), and the SG and SH angles (r = 0.488; p = 0.034). This study showed an immediate effect of trimming on the toe angle and heel angle and on the metacarpophalangeal joint angle, in addition to correlations between the hoof and proximal joint angles, following trimming, thus evidencing the relevance of trimming not only in hoof morphology, but also in the conformation of the appendicular skeleton of horses.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

公众号