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Ben Schwan 《Bioethics》2021,35(1):6-14
It is natural to think that there is a tight connection between whether someone is responsible for some outcome and whether it is appropriate to hold her accountable for that outcome. And this natural thought naturally extends to health: if someone is responsible for her health, then, all else being equal, she is accountable for it. Given this, some have thought that responsibility for health has an important role to play in distributing the benefits and burdens of healthcare. But there is a reason for caution. That health is influenced by social, economic, and environmental factors is a matter of consensus. And some have argued that in light of these social determinants of health, individuals are not typically responsible for their health, rendering inappropriate policies that employ a responsibility‐for‐health criterion. This debate implicates a number of overlapping concepts and questions that are often difficult to pull apart. And I worry that those who maintain that social determinants undermine responsibility for health have latched on to the wrong target. The social determinants of health are relevant to such policies, but, I argue, not by globally undermining responsibility. Rather, social determinants are sometimes responsibility‐undermining, sometimes responsibility‐preserving, and often relevant to whether we should hold individuals accountable for their health regardless of their responsibility. This calls for a more nuanced appraisal of the ways in which the social determinants of health are relevant to such policies. And here I attempt to provide one. 相似文献
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维吾尔族的体质特征研究 总被引:37,自引:12,他引:25
1991年5月,对新疆伊梨维吾尔族529人(男271,女258)进行了活体观察和测量。观察29项,测量92项。维吾尔族的主要特征是:黑直发,黑褐色眼,眉毛较浓密,大都有上眼脸皱褶,鼻根中等偏高,大多为直形鼻,鼻尖向前,鼻基部下垂,大多有达尔文结节,耳垢湿型。头面部指数分型,属于特短头型,阔头型和高头型。身材中等偏高,平均身高男168.6毫米,女1578.8毫米。 相似文献
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草基—鱼塘生态系统的能量转化与养分循环研究 总被引:7,自引:2,他引:5
应用模拟试验的方法,研究了“草基-鱼塘”系统中的能量转化与养分循环.结果 表明,该系统中饲草对太阳能的利用率为 0. 83%,鱼对饲料能的转化率为 7. 3%.与以粮 食作为鱼饲料比较,单位面积草地的产鱼当量是粮食作物的1.6倍.鱼对饲料N、P、K的 转化率分别为16.8%、32.3%和2.0%.塘泥沉积的N、P分别占饲料的23.4%和56.1%; 猪对饲料 N、 P、 K的转化率分别为 20. 5%、 33. 7%和 4. 6%,猪粪尿回收饲料 N为 36. 4%、 P为 63. 8%、 K为 39. 4%.猪-草-鱼结合的基塘系统其能量和养分转化效率均高于单一的 养鱼系统. 相似文献
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Zana R. Majeed Josh Titlow H. Bernard Hartman Robin Cooper 《Journal of visualized experiments : JoVE》2013,(80)
The primary purpose of these procedures is to demonstrate for teaching and research purposes how to record the activity of living primary sensory neurons responsible for proprioception as they are detecting joint position and movement, and muscle tension. Electrical activity from crustacean proprioceptors and tension receptors is recorded by basic neurophysiological instrumentation, and a transducer is used to simultaneously measure force that is generated by stimulating a motor nerve. In addition, we demonstrate how to stain the neurons for a quick assessment of their anatomical arrangement or for permanent fixation. Staining reveals anatomical organization that is representative of chordotonal organs in most crustaceans. Comparing the tension nerve responses to the proprioceptive responses is an effective teaching tool in determining how these sensory neurons are defined functionally and how the anatomy is correlated to the function. Three staining techniques are presented allowing researchers and instructors to choose a method that is ideal for their laboratory. 相似文献
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生物信息学中,发现、鉴别新基因是承上启下的一步,它既承接了过往如“基因组测序”的工作,又是未来“后基因时代”研究的基石.“基因电脑克隆”是利用计算手段发现、鉴别新基因的方法,SiClone软件实现了“基因电脑克隆”功能.本文对SiClone软件操作的数据库提出并行处理方案,并详述了基于MPI(message passing interface)平台实现的并行优化版本PSiClone.根据已得到的EST数据库,展示了软件并行版PSiClone的运行性能,试验数据库EST序列条数仅仅是NCBI(The National Center for Biotechnology Information)dbEST庞大数据库的很小部分,这也暗示我们软件的并行工作对于大数据库的比较和运算将更有应用前景. 相似文献
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Gregorio Moreno-Rueda 《Journal of Ethology》2007,25(3):215-222
Offspring should demand more food than the optimal amount for the parents to bring (parent–offspring conflict), and models
on the evolution of parent–offspring communication suggest that an equilibrium is reached when the costs associated with begging
make it unprofitable for the offspring to increase its level of begging. Empirical evidence for this cost, however, is mixed,
and the conclusions of most of authors are that begging is inexpensive. In this study, the existing empirical evidence for
this cost is reviewed. One cost proposed is the attraction of predators due to begging calls, but empirical support for this
cost is low. However, studies performed cannot dismiss such a cost. Another possible cost is the metabolic expenditure, but
empirical evidence for this cost is mixed, with some works contending that it is low, while others deem it important. Other
possible metabolic costs have not been studied. A loss of inclusive fitness may be an important cost for the evolution of
begging, and robust empirical evidence does exist for this cost. Costs associated with brood reduction also are reviewed.
In conclusion, there is not enough empirical evidence to test the models on the evolution of begging. Most costs proposed
have not yet been studied or the approach used has been insufficient to reject the null hypothesis (i.e., absence of cost). 相似文献
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Pennello GA 《Biometrical journal. Biometrische Zeitschrift》2007,49(1):78-93
An alternative to frequentist approaches to multiple comparisons is Duncan's k-ratio Bayes rule approach. The purpose of this paper is to compile key results on k-ratio Bayes rules for a number of multiple comparison problems that heretofore, have only been available in separate papers or doctoral dissertations. Among other problems, multiple comparisons for means in one-way, two-way, and treatments-vs.-control structures will be reviewed. In the k-ratio approach, the optimal joint rule for a multiple comparisons problem is derived under the assumptions of additive losses and prior exchangeability for the component comparisons. In the component loss function for a comparison, a balance is achieved between the decision losses due to Type I and Type II errors by assuming that their ratio is k. The component loss is also linear in the magnitude of the error. Under the assumption of additive losses, the joint Bayes rule for the component comparisons applies to each comparison the Bayes test for that comparison considered alone. That is, a comparisonwise approach is optimal. However, under prior exchangeability of the comparisons, the component test critical regions adapt to omnibus patterns in the data. For example, for a balanced one-way array of normally distributed means, the Bayes critical t value for a difference between means is inversely related to the F ratio measuring heterogeneity among the means, resembling a continuous version of Fisher's F-protected least significant difference rule. For more complicated treatment structures, the Bayes critical t value for a difference depends intuitively on multiple F ratios and marginal difference(s) (if applicable), such that the critical t value warranted for the difference can range from being as conservative as that given by a familywise rule to actually being anti-conservative relative to that given by the unadjusted 5%-level Student's t test. 相似文献
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研究结果表明:降水施肥与轮作均可提高旱地水分生产效率,降水作用大于施肥和轮作;一年两熟虽可提高水分生产效率,但产量不稳,只适用于半湿润易旱地区的丰水年,一年一熟和三年四熟稳产性高,适于半干旱和半干旱偏湿地区;在各轮作方式中,均以有大豆参加的为最优,粮油轮作次之,有玉米和绿豆的最差。 相似文献
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应用模拟试验的方法,研究了“草基-鱼塘”系统中的能量转化与养分循环.结果表明,该系统中饲草对太阳能的利用率为0.83%,鱼对饲料能的转化率为7.3%.与以粮食作为鱼饲料比较,单位面积草地的产鱼当量是粮食作物的1.6倍.鱼对饲料N、P、K的转化率分别为16.8%、32.3%和2.0%.塘泥沉积的N、P分别占饲料的23.4%和56.1%;猪对饲料N、P、K的转化率分别为20.5%、33.7%和4.6%,猪粪尿回收饲料N为36.4%、P为63.8%、K为39.4%.猪-草-鱼结合的基塘系统其能量和养分转化效率均高于单一的养鱼系统. 相似文献
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This study is an ethical reflection on the formulation and application of public policies regarding reproductive health in Brazil. The Integral Assistance Program for Women's Health (PAISM) can be considered advanced for a country in development. Universal access for family planning is foreseen in the Brazilian legislation, but the services do not offer contraceptive methods for the population in a regular and consistent manner. Abortion is restricted by law to two cases: risk to the woman's life and rape. This reality favors the practice of unsafe abortion, which is the third largest cause of maternal death in Brazil. Legal abortion is regulated by the State and the procedure is performed in public health centers. However, there is resistance on the part of professionals to attend these women. Prenatal care is a priority strategy for promoting the quality of life of these women and of future generations. Nonetheless, it is still difficult for these women to access the prenatal care services and to have the required number of consultations. Moreover, managers and health professionals need to be made aware of the importance of implementing the actions indicated by the public policies in the area of sexual and reproductive health, favoring respect for autonomy in a context of personal freedom. 相似文献
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Rishu Gupta Maya Debbaneh Daniel Butler Monica Huynh Ethan Levin Argentina Leon John Koo Wilson Liao 《Journal of visualized experiments : JoVE》2013,(77)
Psoriasis is a chronic, immune-mediated inflammatory skin disease affecting approximately 2-3% of the population. The Goeckerman regimen consists of exposure to ultraviolet B (UVB) light and application of crude coal tar (CCT). Goeckerman therapy is extremely effective and relatively safe for the treatment of psoriasis and for improving a patient''s quality of life. In the following article, we present our protocol for the Goeckerman therapy that is utilized specifically at the University of California, San Francisco. This protocol details the preparation of supplies, administration of phototherapy and application of topical tar. This protocol also describes how to assess the patient daily, monitor for adverse effects (including pruritus and burning), and adjust the treatment based on the patient''s response. Though it is one of the oldest therapies available for psoriasis, there is an absence of any published videos demonstrating the process in detail. The video is beneficial for healthcare providers who want to administer the therapy, for trainees who want to learn more about the process, and for prospective patients who want to undergo treatment for their cutaneous disease. 相似文献
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根层与表层土壤水分的关系, 是由较易获取的表层土壤水分信息去探讨较难获取的深层土壤水分信息的重要桥梁。已有的根层与表层土壤水分关系(简称根表关系)大都基于一种作物或一种生态系统。该文根据我国生态系统研究网络, 包括森林、草地、农田、荒漠和沼泽生态系统的31个站点109个观测场2006年全年3437对根层和表层土壤水分数据, 研究了根表关系以及生态系统、土壤质地、湿润度、植被、土壤厚度和土壤水分量级对根表关系的影响。研究发现, 表层和根层土壤水分存在着线性关系。森林和沼泽的根层与表层土壤水分相关程度较高, 无论是率定段还是校核段, 其决定系数(R2)均大于0.79。农田和草地生态系统的率定段相关性较好, R 2均大于0.80, 校核段相关性稍弱, R 2分别为0.70和0.50。荒漠生态系统的相关关系最弱, 率定段的R2为0.62, 校核段的R2为0.49。土壤质地和生态系统因素对根表关系的影响较为一致。半湿润带、半干旱带和干旱带的根表关系空间分异性最强; 十分湿润带的根表关系与壤土和森林生态系统的根表关系相对应。湿润带内部的根表关系较为一致。将植被对根表关系的影响分为4类, 前两类为根表关系微弱的植被, 由植被本身或者植被以外的地域因素导致, 不适合用根表关系去由表层推算根层土壤水分; 后两类为根表关系良好植被, 区别为服从和不服从关系总线, 可分别用各自的根表关系或者关系总线从表层土壤水分获取根层土壤水分。表层土壤水分与0-20、0-30、……、0-100 cm土层的土壤水分均分别具有较好的相关关系, 但二者的相关性随土层厚度的增加而降低。不过, 即使是土层厚度抵及100 cm, R 2仍能维持在0.79。通过将土壤水分分别除以所有观测数据的最大值(“标甲”法)和各个生态系统数据的最大值(“标乙”法), 发现根表关系不受土壤水分量级本身的影响。 相似文献
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G. M. Sawyer 《Soil & Sediment Contamination》1996,5(3):261-300
This article describes a method for the determination of gasoline range, diesel range, and mineral oil range organics in soils and water. It represents the culmination of a series of efforts to go beyond typical GRO and DRO methodology currently available in the literature to include a quantitative determination of mineral oil organics having a boiling range up to C44. It also is the result of an attempt to develop a cost‐effective method that enables the analyst to quantify three different types of hydrocarbon components in one GC run under conditions without a concentration step. Method performance is comparable to that of current protocols for GRO and DRO determinations and validated further by comparisons to certified standards and in‐house standards. Accuracy as percentage recovery for GRO in water is 82 to 84 and 91 to 92% for soils. Accuracy as percentage recovery for MRO in water is 84 to 102 and 75 to 80% for soils. Accuracy as percentage recovery for DRO in water is 78 to 100 and 71 to 90% for soils. Results from the analysis of in‐house standards and certified standards for DRO and MRO gave higher recoveries than was demonstrated in the MDL studies. The MDL for DRO in water is 31 mg/l and 14 mg/kg for soils. The MDL for GRO in water is 8 mg/l and 4 mg/kg for soils. For MRO in water, the MDL is 7 mg/l and for soils 10 mg/kg. Future proposed improvements to this method will involve updated software that will allow automatic blank subtraction, automatic calculation of surrogate recoveries and the automatic incorporation of dry weight factors in the final calculations for soils. In addition, a GRO method with a run time of only 24 min will be used routinely when only GRO analyses have to be performed. 相似文献
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When it comes to fitting simple allometric slopes through measurement data, evolutionary biologists have been torn between regression methods. On the one hand, there is the ordinary least squares (OLS) regression, which is commonly used across many disciplines of biology to fit lines through data, but which has a reputation for underestimating slopes when measurement error is present. On the other hand, there is the reduced major axis (RMA) regression, which is often recommended as a substitute for OLS regression in studies of allometry, but which has several weaknesses of its own. Here, we review statistical theory as it applies to evolutionary biology and studies of allometry. We point out that the concerns that arise from measurement error for OLS regression are small and straightforward to deal with, whereas RMA has several key properties that make it unfit for use in the field of allometry. The recommended approach for researchers interested in allometry is to use OLS regression on measurements taken with low (but realistically achievable) measurement error. If measurement error is unavoidable and relatively large, it is preferable to correct for slope attenuation rather than to turn to RMA regression, or to take the expected amount of attenuation into account when interpreting the data. 相似文献
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Although glutamine is used as a major substrate for the growth of mammalian cells in culture, it suffers from some disadvantages. Glutamine is deaminated through storage or by cellular metabolism, leading to the formation of ammonia which can result in growth inhibition. Non-ammoniagenic alternatives to glutamine have been investigated in an attempt to develop strategies for obtaining improved cell yields for ammonia sensitive cell lines.Glutamate is a suitable substitute for glutamine in some culture systems. A period of adaptation to glutamate is required during which the activity of glutamine synthetase and the rate of transport of glutamate both increase. The cell yield increases when the ammonia accumulation is decreased following culture supplementation with glutamate rather than glutamine. However some cell lines fail to adapt to growth in glutamate and this may be due to a low efficiency transport system.The glutamine-based dipeptides, ala-gln and gly-gln can substitute for glutamine in cultures of antibody-secreting hybridomas. The accumulation of ammonia in these cultures is less and cell yields in dipeptide-based media may be improved compared to glutamine-based controls. In murine hybridomas, a higher concentration of gly-gln is required to obtain comparable cell growth to ala-gln or gln-based cultures. This is attributed to a requirement for dipeptide hydrolysis catalyzed by an enzyme with higher affinity for ala-gln than gly-gln. 相似文献
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Vonsattel JP Amaya Mdel P Cortes EP Mancevska K Keller CE 《Cell and tissue banking》2008,9(3):247-258
Generally accepted methods for processing postmortem brains are lacking, despite the efforts of pioneers in the field, and the growing awareness of the importance of brain banking for investigating the pathogenesis of illnesses unique to humans. Standardizing methods requires compromises, institutional or departmental mindset promoting collaboration, and the willingness to share ideas, information, and samples. A sound balance between competition and institutional interests is needed to best fulfill the tasks entrusted to health care institutions. Thus, a potentially widely accepted protocol design involves tradeoffs. We successfully integrated brain banking within the operation of the department of pathology. We reached a consensus whereby a brain can be utilized for diagnosis, research, and teaching. Thus, routing brains away from residency programs is avoided. The best diagnostic categorization possible is being secured and the yield of samples for research maximized. Thorough technical details pertaining to the actual processing of brains donated for research were recently published. Briefly, one-half of each brain is immersed in formalin for performing the neuropathologic evaluation, which is combined with the teaching task. The contralateral half is extensively dissected at the fresh state to obtain samples ready for immediate disbursement once categorized diagnostically. The samples are tracked electronically, which is crucial. This important tracking system is described separately in this issue. This report focuses on key lessons learned over the past 25 years of brain banking including successful solutions to originally unforeseen problems. 相似文献
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We consider Bayesian methodology for comparing two or more unlabeled point sets. Application of the technique to a set of steroid molecules illustrates its potential utility involving the comparison of molecules in chemoinformatics and bioinformatics. We initially match a pair of molecules, where one molecule is regarded as random and the other fixed. A type of mixture model is proposed for the point set coordinates, and the parameters of the distribution are a labeling matrix (indicating which pairs of points match) and a concentration parameter. An important property of the likelihood is that it is invariant under rotations and translations of the data. Bayesian inference for the parameters is carried out using Markov chain Monte Carlo simulation, and it is demonstrated that the procedure works well on the steroid data. The posterior distribution is difficult to simulate from, due to multiple local modes, and we also use additional data (partial charges on atoms) to help with this task. An approximation is considered for speeding up the simulation algorithm, and the approximating fast algorithm leads to essentially identical inference to that under the exact method for our data. Extensions to multiple molecule alignment are also introduced, and an algorithm is described which also works well on the steroid data set. After all the steroid molecules have been matched, exploratory data analysis is carried out to examine which molecules are similar. Also, further Bayesian inference for the multiple alignment problem is considered. 相似文献
19.
Collecting natural data at regular, fine scales is an onerous and often costly procedure. However, there is a basic need for fine scale data when applying inductive methods such as neural networks or genetic algorithms for the development of ecological models. This paper will address the issues involved in interpolating data for use in machine learning methods by considering how to determine if a downscaling of the data is valid. The approach is based on a multi-scale estimate of errors. The resulting function has similar properties to a time series variogram; however, the comparison at different scales is based on the variance introduced by rescaling from the original sequence. This approach has a number of properties, including the ability to detect frequencies in the data below the current sampling rate, an estimate of the probable average error introduced when a sampled variable is downscaled and a method for visualising the sequences of a time series that are most susceptible to error due to sampling. The described approach is ideal for supporting the ongoing sampling of ecological data and as a tool for assessing the impact of using interpolated data for building inductive models of ecological response. 相似文献
20.
Adaptation to environmental challenges is critical for the survival of an organism. Repression of Insulin/IGF Signaling (IIS) by stress-responsive Jun-N-terminal Kinase (JNK) signaling is emerging as a conserved mechanism that allows reallocating resources from anabolic to repair processes under stress conditions. JNK activation in Insulin-producing cells (IPCs) is sufficient to repress Insulin and Insulin-like peptide (ILP) expression in rats and flies, but the significance of this interaction for adaptive responses to stress is unclear. In this study, it is shown that JNK activity in IPCs of flies is required for oxidative stress-induced repression of the Drosophila ILP2. It is found that this repression is required for growth adaptation to heat stress as well as adult oxidative stress tolerance, and that induction of stress response genes in the periphery is in part dependent on IPC-specific JNK activity. Endocrine control of IIS by JNK in IPCs is thus critical for systemic adaptation to stress. 相似文献