Mathematics

数学
  • 文章类型: Journal Article
    在此符合PRISMA的系统审查中,我们确定并综合了神经影像学和成就评估已用于检查发展规划各方面之间的关系的研究结果,神经发育,在阅读和数学方面的成就。
    47项研究符合纳入标准。大多数人检查了早产(n=32)和产前酒精暴露(n=13)的影响。一些早产研究报告了call骨纤维白质完整性与执行功能和/或成就之间的正相关。在早产儿和足月儿童中,白质特性与认知和学习成绩始终相关.体积研究报告了学术和认知能力与脑岛等区域的白质和灰质体积之间的正相关关系,壳核,和前额叶。功能性MRI研究表明,早产儿的右半球语言处理增加。还报道了与数值能力有关的额顶网络的激活改变。产前酒精暴露研究报告了白质微结构的改变与认知功能和学业成绩的缺陷有关。包括数学,阅读,和词汇技能。体积研究报告大脑减少,小脑,与执行功能测量得分降低相关的皮层下灰质体积,注意,工作记忆,和学习成绩。功能磁共振成像研究证明广泛,弥漫性激活,规范区域的激活减少,并在数字任务期间增加非规范区域的激活。
    大量研究将早产和产前酒精暴露与改变的神经发育过程和次优的学业成绩联系起来。讨论了局限性和对未来研究的建议。
    标识符:DOI10.17605/OSF。IO/ZAN67。
    UNASSIGNED: In this PRISMA-compliant systematic review, we identify and synthesize the findings of research in which neuroimaging and assessments of achievement have been used to examine the relationships among aspects of developmental programming, neurodevelopment, and achievement in reading and mathematics.
    UNASSIGNED: Forty-seven studies met inclusion criteria. The majority examined the impact of prematurity (n = 32) and prenatal alcohol exposure (n = 13). Several prematurity studies reported a positive correlation between white-matter integrity of callosal fibers and executive functioning and/or achievement, and white matter properties were consistently associated with cognitive and academic performance in preterm and full-term children. Volumetric studies reported positive associations between academic and cognitive abilities and white and gray matter volume in regions such as the insula, putamen, and prefrontal lobes. Functional MRI studies demonstrated increased right-hemispheric language processing among preterm children. Altered activation of the frontoparietal network related to numerical abilities was also reported. Prenatal alcohol exposure studies reported alterations in white matter microstructure linked to deficits in cognitive functioning and academic achievement, including mathematics, reading, and vocabulary skills. Volumetric studies reported reductions in cerebral, cerebellar, and subcortical gray matter volumes associated with decreased scores on measures of executive functioning, attention, working memory, and academic performance. Functional MRI studies demonstrated broad, diffuse activation, reduced activation in canonical regions, and increased activation in non-canonical regions during numeric tasks.
    UNASSIGNED: A preponderance of studies linked prematurity and prenatal alcohol exposure to altered neurodevelopmental processes and suboptimal academic achievement. Limitations and recommendations for future research are discussed.
    UNASSIGNED: Identifier: DOI 10.17605/OSF.IO/ZAN67.
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  • 文章类型: Journal Article
    背景:导师对研究生科学的成功至关重要,技术,工程,数学,和药物(STEMM)设置。因此,这项研究的目的是全面探索研究生STEMM设置中导师干预的状态,以确定新颖的实践和未来的研究方向。评审文章的选择标准包括:1)在2002年至2022年之间发表,2)同行评审,3)在英语中,4)研究生学员,5)指导是一个重要的项目,明确的焦点,和6)描述与导师干预相关的受训者结果。总的来说,筛选了2583篇文章,共审查了109篇文章。
    结果:大多数研究生STEMM指导干预研究缺乏强有力的证据来评估干预的有效性,只有5.5%的文章设计为随机对照试验。大多数导师干预措施(45.6%)是为教师创建的,很少(4%)是博士后研究人员。此外,只有18.8%的干预措施集中于STEMM中代表性不足的群体.大多数干预措施(53.7%)规定了二元结构,导师的导师培训多于受训者。
    结论:总体而言,这些发现确定了导师干预措施的差距,并为未来的干预措施提供了逐步的指导,包括对代表性不足的群体和博士后学者的考虑,强大的指导培训,和更多的随机对照试验。
    BACKGROUND: Mentorship is critical to success in postgraduate science, technology, engineering, math, and medicine (STEMM) settings. As such, the purpose of this study is to comprehensively explore the state of mentorship interventions in postgraduate STEMM settings to identify novel practices and future research directions. The selection criteria for reviewed articles included: 1) published between 2002 and 2022, 2) peer-reviewed, 3) in English, 4) postgraduate mentees, 5) a program where mentorship is a significant, explicit focus, and 6) a description of mentee outcomes related to the mentorship intervention. Overall, 2583 articles were screened, and 109 articles were reviewed.
    RESULTS: Most postgraduate STEMM mentorship intervention studies lack strong evidence to evaluate the effectiveness of the intervention, with only 5.5% of articles designed as randomized controlled trials. Most mentorship interventions (45.6%) were created for faculty, and few (4%) were for postdoctoral researchers. Also, only 18.8% of interventions focused on underrepresented groups in STEMM. Most interventions (53.7%) prescribed a dyadic structure, and there was more mentorship training for mentors than mentees.
    CONCLUSIONS: Overall, these findings identify gaps in mentorship interventions and provide step-by-step guidance for future interventions, including a consideration for underrepresented groups and postdoctoral scholars, robust mentorship training, and more randomized controlled trials.
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  • 文章类型: Journal Article
    众所周知,科学,技术,工程,和数学(STEM)领域有独特的挑战,阻碍招募和保留代表性不足的少数民族。针对本科生的研究计划已经成为促进创新和解决代表性不足的少数群体面临的挑战的关键机制。这里,我们回顾了各种旨在为本科生提供接触的本科研究计划,重点关注STEM学科中代表性不足的少数民族。我们提供对选定计划目标的洞察,主要功能,潜在的限制,和结果。我们还为每个研究计划的未来改进提供建议,特别是在导师的背景下。这些计划的范围从广泛的倡议(例如,领导力联盟)针对代表性不足的学生的更具体的计划。通过对每个程序的结构提供细致入微的理解,我们寻求提供以多样性为重点的STEM计划的景观的简要概述,以及如何有效运行研究计划的指南。
    It is well-understood that the science, technology, engineering, and mathematics (STEM) fields have unique challenges that discourage recruiting and retaining underrepresented minorities. Research programs aimed at undergraduates have arisen as a critical mechanism for fostering innovation and addressing the challenges faced by underrepresented minorities. Here, we review various undergraduate research programs designed to provide exposure to undergraduates, with a focus on underrepresented minorities in STEM disciplines. We provide insight into selected programs\' objectives, key features, potential limitations, and outcomes. We also offer recommendations for future improvements of each research program, particularly in the context of mentorship. These programs range from broad-reaching initiatives (e.g., Leadership Alliance) to more specific programs targeting underrepresented students. By offering a nuanced understanding of each program\'s structure, we seek to provide a brief overview of the landscape of diversity-focused STEM initiatives and a guide on how to run a research program effectively.
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  • 文章类型: Systematic Review
    本系统综述对将经颅磁刺激和经颅电刺激应用于顶叶和非顶叶区域以检查符号算术处理的神经基础的研究进行了全面调查。所有发现都是根据数字处理的三重代码模型(TCM)的三个假设进行的。确定了37份合格的手稿进行审查(33份健康参与者和4份患者)。他们的结果与TCM的第一个假设基本一致,即顶内沟既具有幅度代码,又从事需要数字操作的操作,例如减法。然而,在很大程度上异质的结果与中医的第二个假设相冲突,即左角回服从算术事实检索,如检索死记硬背的乘法结果。对中医第三个假设的支持也是有限的,即,后上顶叶小叶在精神数字线上进行空间操作。此外,来自中医假设以外的大脑区域的刺激结果表明,双侧上脑回参与在线计算和检索,左颞叶皮层在检索中,以及双侧背外侧前额叶皮层和小脑在在线计算中的认知要求很高的算术问题。总体结果表明,多个皮质区域都符合算术技能。
    This systematic review presented a comprehensive survey of studies that applied transcranial magnetic stimulation and transcranial electrical stimulation to parietal and nonparietal areas to examine the neural basis of symbolic arithmetic processing. All findings were compiled with regard to the three assumptions of the triple-code model (TCM) of number processing. Thirty-seven eligible manuscripts were identified for review (33 with healthy participants and 4 with patients). Their results are broadly consistent with the first assumption of the TCM that intraparietal sulcus both hold a magnitude code and engage in operations requiring numerical manipulations such as subtraction. However, largely heterogeneous results conflicted with the second assumption of the TCM that the left angular gyrus subserves arithmetic fact retrieval, such as the retrieval of rote-learned multiplication results. Support is also limited for the third assumption of the TCM, namely, that the posterior superior parietal lobule engages in spatial operations on the mental number line. Furthermore, results from the stimulation of brain areas outside of those postulated by the TCM show that the bilateral supramarginal gyrus is involved in online calculation and retrieval, the left temporal cortex in retrieval, and the bilateral dorsolateral prefrontal cortex and cerebellum in online calculation of cognitively demanding arithmetic problems. The overall results indicate that multiple cortical areas subserve arithmetic skills.
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  • 文章类型: Systematic Review
    中国小学生数学困难(MD)的患病率及其相关因素尚不清楚。为制定适当的筛查和干预策略提供适当的基础,本研究旨在评估中国小学生中MD的患病率及其可能因素。从七个数据库中确定了文章,并包括了他们是否报告了中国小学生中MD的患病率。共检索到30881篇,其中975个进行了全面评估。总的来说,包括54项研究,涉及34,815名参与者(平均年龄9.86±3.13岁)。在统计软件环境R中使用Meta和Metafor软件包进行分析。我们使用meta回归和变量类型的亚组分析来评估潜在的患病率因素。中国小学生中MD的合并患病率为8.97%,而MD的患病率较低,中间,高年级小学占11.57%,10.07%,4.76%,分别。结果表明,中国小学儿童的MD患病率与年级水平和筛查MD所选择的临界点显着相关,初中小学的MD患病率女孩高于男孩。中国小学的MD患病率略高于英国和美国等国家。小学中低年级的MD患病率较高。在MD筛查过程中选择的等级和截止点与MD的患病率密切相关。应更多关注初中女孩的MD。
    https://www.crd.约克。AC.uk/prospro/display_record.php?ID=CRD42023410311,标识符:CRD42023410311。
    The prevalence of mathematical difficulties (MD) among primary school children in China and its related factors remain unclear. To provide a suitable foundation for formulating appropriate screening and intervention strategies, this study aimed to estimate the prevalence of MD and its possible factors among primary school children in China. Articles were identified from seven databases and included if they reported on the prevalence of MD among primary school children in China. A total of 30,881 articles were retrieved, 975 of which were subjected to full evaluation. In total, 54 studies involving 34,815 participants (mean age 9.86 ± 3.13 years) were included. Analyses were conducted using the Meta and Metafor packages in the statistical software environment R. We used meta-regression and subgroup analyses by variable type to evaluate the potential prevalence factors. The pooled prevalence of MD among primary school children in China was 8.97%, whereas the prevalence rates of MD in lower, middle, and upper primary schools were 11.57%, 10.07%, and 4.76%, respectively. The results showed that the prevalence of MD among primary school children in China was significantly related to grade level and the cut-off points selected for screening MD and that the prevalence of MD in middle primary school was higher in girls than in boys. The prevalence of MD in primary schools in China was slightly higher than that in countries such as the United Kingdom and the United States. The prevalence of MD was higher in the lower and middle grades of primary school. The grade level and cut-off points selected during MD screening were closely related to the prevalence of MD. More attention should be paid to girls with MD in middle primary school.
    https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023410311, identifier: CRD42023410311.
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  • 文章类型: Meta-Analysis
    我们进行了系统评价和荟萃分析,以检查阅读困难(RD)的个体数学困难(MD),或未指定的学习困难(ULD)经历内化问题(即,焦虑,抑郁症,躯体投诉,和社会退缩)在相同程度上,如果效果大小受到主持人的影响(年龄,内化问题类型,焦虑类型,评分器类型,选择标准,和注意力控制)。我们回顾了2000年1月至2023年4月之间以英文发表的2,806项研究。我们的最终样本由96项研究组成,这些研究报告了效应大小或数据来计算它们(总共120个独特样本,83,260名与会者,年龄范围=7.3-34.8岁)。评估偏倚和敏感性的风险。随机效应模型分析揭示了显著和中等的总体效应大小(对冲g=-.54),表明有RD的人,MD或ULD比他们的实际年龄(CA)对照经历更多的内在化问题。后续分析表明,学习困难类型和参与者的年龄都不是显著的调节因素,但选择标准(诊断与筛查)和内化问题类型为.这些发现表明,在内在化问题上,患有RD的个体与患有MD或ULD的个体没有区别,与CA对照相比,所有票价都很差。
    We conducted a systematic review and meta-analysis to examine if individuals with reading difficulties (RD), mathematics difficulties (MD), or unspecified learning difficulties (ULD) experience internalizing problems (i.e., anxiety, depression, somatic complaints, and social withdrawal) to the same extent, and if the effect sizes are influenced by moderators (age, internalizing problems type, anxiety type, rater type, selection criteria, and attention control). We reviewed 2,806 studies published in English between January 2000 and April 2023. Our final sample consisted of 96 studies that reported effect sizes or data to calculate them (a total of 120 unique samples, 83,260 participants, age range = 7.3 - 34.8 years). Risk of bias and sensitivity were assessed. A random-effects model analysis revealed a significant and moderate overall effect size (Hedge\'s g = -.54), indicating that individuals with RD, MD or ULD experience more internalizing problems than their chronological-age (CA) controls. Follow-up analyses showed that neither learning difficulties type nor age of participants were significant moderators, but selection criteria (diagnosis versus screening) and internalizing problems type were. These findings suggest that individuals with RD do not differ from those with MD or ULD in internalizing problems, and all fare poorly compared to CA controls.
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  • 文章类型: Journal Article
    数学通常被视为不同于其他学科,因为该领域的论证依赖于演绎证明,而不是自然科学中的经验证据。因此,数学论文可以,至少在原则上,只需阅读它就可以复制。虽然这种区别有时被视为声称数学结果是确定的基础,数学家自己知道,发表的文献包含许多错误。阅读证明并不容易,检查论点是否构成证明是出奇的困难。本文使用同行评审对数学期刊的投稿,作为裁判明确关注检查论文是否正确并因此可以发表的网站。借鉴了对数学期刊编辑的95次定性采访,以及来自同行评审过程的100多份裁判报告和其他信件的集合,这篇文章指出,虽然数学家承认同行评审不能保证正确性,他们仍然重视它。对于数学家来说,同行评审“增加了一点确定性”,特别是与仅提交给arXiv等预印本服务器的论文相反。此外,在同行评审期间,可能会有分歧,而不仅仅是关于结果的重要性,而且还包括一个特定的论点是否构成证明(特别是,证明中是否存在实质性差距)。最后,当涉及到接受论点作为证明并为结果赋予确定性时,数学界被认为是重要的。在同行评审的期刊上发表论点通常只是接受结果的第一步。如果结果经得起时间的考验并被其他数学家使用,它们就会被接受。
    Mathematics is often treated as different from other disciplines, since arguments in the field rely on deductive proof rather than empirical evidence as in the natural sciences. A mathematical paper can therefore, at least in principle, be replicated simply by reading it. While this distinction is sometimes taken as the basis to claim that the results in mathematics are therefore certain, mathematicians themselves know that the published literature contains many mistakes. Reading a proof is not easy, and checking whether an argument constitutes a proof is surprisingly difficult. This article uses peer review of submissions to mathematics journals as a site where referees are explicitly concerned with checking whether a paper is correct and therefore could be published. Drawing on 95 qualitative interviews with mathematics journal editors, as well as a collection of more than 100 referee reports and other correspondence from peer review processes, this article establishes that while mathematicians acknowledge that peer review does not guarantee correctness, they still value it. For mathematicians, peer review \'adds a bit of certainty\', especially in contrast to papers only submitted to preprint servers such as arXiv. Furthermore, during peer review there can be disagreements not just regarding the importance of a result, but also whether a particular argument constitutes a proof or not (in particular, whether there are substantial gaps in the proof). Finally, the mathematical community is seen as important when it comes to accepting arguments as proofs and assigning certainty to results. Publishing an argument in a peer-reviewed journal is often only the first step in having a result accepted. Results get accepted if they stand the test of time and are used by other mathematicians.
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  • 文章类型: Journal Article
    背景:揭示现有教学内容知识或技术教学内容知识框架及其在数学教学中的有效性的研究对于告知读者至关重要,老师,和研究员。本综述研究旨在探讨教学内容知识(PCK)框架的发展趋势,随着时间的推移,它是如何变化的,直到最新版本的技术和教学内容知识(TPACK)被开发出来,以及它们在数学教学中的有效性。
    方法:我们最初从前30个Google学术页面下载了273篇文章,分析了229篇期刊文章。自1986年Shulman的第一个模型以来,我们从64篇期刊文章中获得了24个框架。229个中有52个是数学研究。在这些研究中,我们发现有18项研究广泛调查了已确定框架的使用情况.
    结果:按时间顺序介绍并描述讨论了框架。证明了实证研究,该研究比较了教室中具有和不具有此类技能的教师的教学内容知识和技术教学内容知识模型的作用。
    结论:发现了实证研究的差距,并建议对PCK和TPACK模型的干预进行进一步研究,以更深入地了解数学课堂。
    BACKGROUND: A study to reveal existing pedagogical content knowledge or technological pedagogical content knowledge frameworks and their effectiveness in teaching mathematics is crucial to inform the reader, teacher, and researcher. This review study intended to explore the trends of the pedagogical content knowledge (PCK) framework, how it has changed over time until the most recent version of technological and pedagogical content knowledge (TPACK) was developed, and their effectiveness in teaching mathematics.
    METHODS: We initially downloaded 273 articles from the first 30 Google Scholar pages and analyzed 229 journal articles. We got 24 frameworks from 64 journal articles since Shulman\'s first model in 1986. About 52 out of 229 were mathematics studies. Among these studies, we found that 18 studies have extensively investigated the use of identified frameworks.
    RESULTS: The frameworks were presented and descriptively discussed in chronological order. The empirical studies that compared the role of pedagogical content knowledge and technological pedagogical content knowledge models among classrooms with teachers who possess and do not possess such skills were demonstrated.
    CONCLUSIONS: The gap in empirical studies was identified, and further studies about the intervention of PCK and TPACK models were suggested to gain more insight into the mathematics classroom.
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  • 文章类型: Journal Article
    数学包含了广泛的技能,其中包括基本的早期算术技能,例如subitizing和基本计数到更高级的辅助技能,包括数学计算和推理。这篇综述的目的是对癫痫患者的早期算术和中等数学技能的严重程度和模式进行详细调查。搜索以系统评论和荟萃分析(PRISMA)声明的首选报告项目为指导。本综述包括20项成人研究和67项儿童研究。总的来说,荟萃分析显示,在两个成年人的所有数学结果中,存在显著的中度损伤(g=-0.676),和儿童(g=-0.593)癫痫。还观察到特定数学结果的缺陷。对于成年人来说,数学推理有损伤(g=-0.736)。然而,两项研究发现,数学计算没有明显受损,研究成年人的早期算术技能的研究数量不足。在患有癫痫的儿童中,每个数学结果都观察到了显著的损伤:早期算术(g=-0.383),计算(g=-0.762),和推理(g=-0.572)。根据儿童和成人的癫痫发作重点部位,损伤的严重程度也有所不同,提示数学结果对癫痫发作病灶的位置有不同的脆弱性.
    Mathematics incorporates a broad range of skills, which includes basic early numeracy skills, such as subitizing and basic counting to more advanced secondary skills including mathematics calculation and reasoning. The aim of this review was to undertake a detailed investigation of the severity and pattern of early numeracy and secondary mathematics skills in people with epilepsy. Searches were guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Twenty adult studies and 67 child studies were included in this review. Overall, meta-analyses revealed significant moderate impairments across all mathematics outcomes in both adults (g= -0.676), and children (g= -0.593) with epilepsy. Deficits were also observed for specific mathematics outcomes. For adults, impairments were found for mathematics reasoning (g= -0.736). However, two studies found that mathematics calculation was not significantly impaired, and an insufficient number of studies examined early numeracy skills in adults. In children with epilepsy, significant impairments were observed for each mathematics outcome: early numeracy (g= -0.383), calculation (g= -0.762), and reasoning (g= -0.572). The gravity of impairments also differed according to the site of seizure focus for children and adults, suggesting that mathematics outcomes were differentially vulnerable to the location of seizure focus.
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  • 文章类型: Journal Article
    在过去的六十年中,已经开发了许多数学营养模型来预测农场动物的饮食供应和能量和蛋白质的需求。虽然这些模型,通常由不同的群体开发,分享相似的概念和数据,他们的计算例程(即,子模型)很少被组合成广义模型。缺乏混合子模型的部分原因是不同的模型具有不同的属性,包括范式,结构性决策,输入/输出,和参数化过程,可能使它们不兼容合并。另一个原因是,由于无法彻底研究的抵消误差,可预测性可能会增加。或者,组合概念可能比组合模型计算例程更易于访问和更安全,因为概念可以在不改变建模结构和计算逻辑的情况下被合并到现有模型中。尽管可能需要额外的投入。而不是开发新的模型,改进现有模型概念的合并可能会减少开发能够评估可持续性方面的模型所需的时间和精力。确保适当饮食配方所需的牛肉生产研究的两个领域包括放牧动物的准确能量需求(减少甲烷排放)和种植牛的能源使用效率(减少car体废物和资源使用)。提出了一种修正的放牧动物能量消耗模型,以纳入身体活动所需的能量,正如英国的喂养系统所建议的那样,以及对总能量需求的进食和反思(HjEer)。不幸的是,所提出的方程只能通过优化迭代求解,因为HjEer需要可代谢能(ME)摄入量。另一个修订后的模型扩展了现有模型,通过包括动物的成熟度和澳大利亚饲喂系统中使用的平均日增重(ADG),从保留能量中的蛋白质比例中估算了使用ME进行生长(kg)的部分效率。修改后的kg模型使用了car体成分,它对饮食中ME含量的依赖性较小,但仍然需要对成熟度和ADG的准确评估,这又取决于千克。因此,它需要迭代求解或使用一步延迟连续计算(即,使用前一天的ADG计算当天的千克)。我们认为,通过合并不同模型概念而开发的广义模型可能会改善我们对现有变量的关系的理解,这些变量以其重要性而闻名,但由于当时缺乏适当的信息或信心,因此不包括在现有模型中。
    Numerous mathematical nutrition models have been developed in the last sixty years to predict the dietary supply and requirement of farm animals\' energy and protein. Although these models, usually developed by different groups, share similar concepts and data, their calculation routines (i.e., submodels) have rarely been combined into generalized models. This lack of mixing submodels is partly because different models have different attributes, including paradigms, structural decisions, inputs/outputs, and parameterization processes that could render them incompatible for merging. Another reason is that predictability might increase due to offsetting errors that cannot be thoroughly studied. Alternatively, combining concepts might be more accessible and safer than combining models\' calculation routines because concepts can be incorporated into existing models without changing the modeling structure and calculation logic, though additional inputs might be needed. Instead of developing new models, improving the merging of extant models\' concepts might curtail the time and effort needed to develop models capable of evaluating aspects of sustainability. Two areas of beef production research that are needed to ensure adequate diet formulation include accurate energy requirements of grazing animals (decrease methane emissions) and efficiency of energy use (reduce carcass waste and resource use) by growing cattle. A revised model for energy expenditure of grazing animals was proposed to incorporate the energy needed for physical activity, as the British feeding system recommended, and eating and rumination (HjEer) into the total energy requirement. Unfortunately, the proposed equation can only be solved iteratively through optimization because HjEer requires metabolizable energy (ME) intake. The other revised model expanded an existing model to estimate the partial efficiency of using ME for growth (kg) from protein proportion in the retained energy by including an animal degree of maturity and average daily gain (ADG) as used in the Australian feeding system. The revised kg model uses carcass composition, and it is less dependent on dietary ME content, but still requires an accurate assessment of the degree of maturity and ADG, which in turn depends on the kg. Therefore, it needs to be solved iteratively or using one-step delayed continuous calculation (i.e., use the previous day\'s ADG to compute the current day\'s kg). We believe that generalized models developed by merging different models\' concepts might improve our understanding of the relationships of existing variables that were known for their importance but not included in extant models because of the lack of proper information or confidence at that time.
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