Radiomics for classification of bone mineral loss: A machine learning study

PurposeThe purpose of this study was to develop predictive models to classify osteoporosis, osteopenia and normal patients using radiomics and machine learning approaches.Materials and methodsA total of 147 patients were included in this retrospective single-center study. There were 12 men and 135 women with a mean age of 56.88 ± 10.6 (SD) years (range: 28–87 years). For each patient, seven regions including four lumbar and three femoral including trochanteric, intertrochanteric and neck were segmented on bone mineral densitometry images and 54 texture features were extracted from the regions. The performance of four feature selection methods, including classifier attribute evaluation (CLAE), one rule attribute evaluation (ORAE), gain ratio attribute evaluation (GRAE) and principal components analysis (PRCA) along with four classification methods, including random forest (RF), random committee (RC), K-nearest neighbor (KN) and logit-boost (LB) were evaluated. Four classification categories, including osteopenia vs. normal, osteoporosis vs. normal, osteopenia vs. osteoporosis and osteoporosis + osteopenia vs. osteoporosis were examined for the defined seven regions. The classification model performances were evaluated using the area under the receiver operator characteristic curve (AUC).ResultsThe AUC values ranged from 0.50 to 0.78. The combination of methods RF + CLAE, RF + ORAE and RC + ORAE yielded highest performance (AUC = 0.78) in discriminating between osteoporosis and normal state in the trochanteric region. The combinations of RF + PRCA and LB + PRCA had the highest performance (AUC = 0.76) in discriminating between osteoporosis and normal state in the neck region.ConclusionThe machine learning radiomic approach can be considered as a new method for bone mineral deficiency disease classification using bone mineral densitometry image features.     

基于关联规则和因子分析研究糖尿病肾病中药组方用药规律

目的 挖掘中医药治疗糖尿病肾病的组方用药规律。方法 以中国知网、万方医学网2012年1月-2018年6月收录的期刊文献为资料来源，使用Excel 2013、SPSS Modeler 14.1、SPSS Statistics 19.0统计软件为工具，对纳入标准的中药进行关联规则分析和因子分析。结果 在纳入标准的215首方剂中，使用频数≥ 30的高频药物共28种，其中黄芪（143次，66.5%），茯苓（113次，52.6%），丹参（97次，45.1%），山药（86次，40.0%），当归（73次，34.0%）最为常见。糖尿病肾病治疗的药物四气以寒（11次，39.2%）、平（10次，35.7%）为主，五味中甘味（23次，50.0%）为主，归经中肝经（16次，20.0%）、脾经（14次，17.5%）居多，使用最多的药物类别为补虚药（912次，39.3%），活血化瘀药（307次，13.2%），关联规则分析中发现关联强度最高的药对组合为12种，因子分析中提取6个公因子。结论 糖尿病肾病的治疗多以甘温药黄芪（补虚药）为主，临床上可与苦寒药丹参，甘平药茯苓等组合使用，以及可随证配伍活血化瘀、清热等药物。     

Focusing climate negotiations on a uniform common commitment can promote cooperation

International cooperation on the reduction of greenhouse gas emissions, disarmament, or free trade needs to be negotiated. The success of such negotiations depends on how they are designed. In the context of international climate change policy, it has been proposed [e.g., M. L. Weitzman J. Assoc. Environ. Resour. Econ. 1, 29–49 (2014)] that shifting the negotiation focus to a uniform common commitment (such as a uniform minimum carbon price) would lead to more ambitious cooperation. Yet, a proof-of-concept for this important claim is lacking. Based on game theoretical analyses, we present experimental evidence that strongly supports this conjecture. In our study, human subjects negotiate contributions to a public good. Subjects differ in their benefits and costs of cooperation. Participation in the negotiations and all commitments are voluntary. We consider treatments in which agreements are enforceable, and treatments in which they have to be self-enforcing. In both situations, negotiating a uniform common commitment is more successful in promoting cooperation than negotiating individual commitments (as in the Paris Agreement) and complex common commitments that tailor the commitment to the specific situation of each party (as attempted with the Kyoto Protocol). Furthermore, as suggested by our model, a uniform common commitment benefits most from being enforced.

International cooperation on climate change, free trade, and disarmament requires successful negotiations about how much each party contributes to the public good. The success or failure of these negotiations depends on how they are designed (1). Particularly, in the context of international climate change policy, it has been hypothesized that negotiating a uniform common commitment would be more successful in achieving cooperation than negotiating individual or complex common commitments (2–5). Yet, a proof-of-concept for this important claim is lacking. Using a laboratory experiment with human subjects and a game theoretical analysis, we fill the gap—and provide strong support for the conjecture.We consider a canonical public good problem. Asymmetry is known to be an essential complication to international agreements (6), so—besides a control with fully symmetric parties—negotiators in our main laboratory treatment differ in their initial endowment, in how much they benefit from the public good, and in how much of it they want to be provided. Lack of enforcement is another fundamental problem that hinders international cooperation (7–9), so we look at a situation where parties can write a binding and enforceable contract and at a situation where the agreement has to be self-enforcing. Negotiations differ in two dimensions. First, parties can negotiate a common goal to be achieved either by individual commitments (each party deciding individually how much to contribute) or by a common commitment (all parties deciding jointly and unanimously on all contributions). Second, a common commitment may be achieved either by a complex assignment (tailoring each individual contribution to its individual costs and benefits) or by a uniform rule (disregarding individual differences). In all treatments, participation in the negotiation and commitments are voluntary.We find that negotiation design is of first-order importance. If negotiations are focused on a uniform common commitment, contribution levels are about twice as high compared to negotiations focusing on individual or complex common commitments. Negotiating a complex common commitment is slightly more successful at the extensive margin by inducing more parties to participate, but it is dominated at the intensive margin by the uniform commitment because negotiators often fail to coordinate any agreement. Negotiating individual commitments is equally as successful as a uniform common commitment in getting parties to participate, but again at substantially lower contribution levels. One reason for the superior performance at the intensive margin is that negotiating a uniform common commitment turns (reciprocal) cooperation into a weakly dominant strategy for all participating parties. The results are robust and hold not only in the case where contracts are binding and enforceable (as predicted by theory) but even in the case where agreements cannot be enforced but have to be self-enforceable (in which case, standard game theory predicts zero cooperation across all treatments).Our study is motivated by, and potentially important for, international negotiations on climate change (5). There have been two major approaches to negotiating international climate cooperation. In the Kyoto negotiations, the developed countries strived for a complex assignment of national emission caps. However, no such assignment (that the negotiating parties could all agree upon) has been found. Eventually, each country chose its emission cap individually, which then became part of the Kyoto Protocol (4, 10). Some countries later withdrew from the Kyoto Protocol, others did not live up to their promises, and a planned follow-up protocol was never ratified.In the Paris negotiations, instead of attempting a common commitment, each country pledged an individually chosen commitment (“nationally determined contributions”). The Paris Agreement succeeded in being signed by all countries (although the United States decided later to withdraw its participation). However, the announced individual commitments fall substantially short of achieving the two-degree goal (11, 12).There is a new proposal that negotiations should focus on a common carbon price (2, 3, 13, 14). Previous authors advocated carbon pricing as an instrument to implement the reduction of carbon emissions at low economic cost (15, 16). The new proposal points to a different and independent argument: A carbon price provides a simple focal point for a common commitment in climate negotiations—one number that applies to all countries in the same way. This facilitates agreement (17) and fosters reciprocity (2, 3, 14, 18, 19) which is key to cooperation (20–24). Yet, evidence showing that negotiating a uniform carbon price can be more successful than negotiating a vector of emissions caps (as in Kyoto) or nationally determined contributions (as in Paris) is lacking.This paper provides evidence, based on experimental and game theoretical analyses, that a uniform common commitment better promotes cooperation than the alternative commitments. The advantage of a laboratory experiment is that it allows study of the negotiation outcomes after exogenous changes in the negotiation design, as well as the mechanisms that causally drive behavior. While all theory and experiments necessarily abstract from many real-world complexities, our study informs the important debate about how to approach climate negotiations by providing a proof-of-concept, experimentally and theoretically, that negotiating a uniform common commitment may be more successful than previous negotiation designs.     

Standardization of plasma vitellogenin level for surveying environmental estrogen pollution using the Japanese common goby Acanthogobius flavimanus

Field surveys of the impact of environmental estrogen (EE) pollution in aquatic wildlife have been conducted using vitellogenin (VTG) as a biomarker to evaluate the influence of EE. However, a standard baseline of VTG level that can be used to evaluate EE pollution has not been fully determined. To the best of our knowledge, the present study is the first to determine the standard baseline VTG level for evaluating the biological effects of EE pollution using the Japanese common goby (Acanthogobius flavimanus) as the target model fish. Plasma VTG and estradiol‐17β (E₂) levels associated with the reproductive cycle of wild goby inhabiting an unpolluted environment were measured. Mean plasma VTG and E₂ levels exhibited similar changes, increasing in the yolk vesicle stage and peaking in the tertiary yolk stage in females. However, plasma VTG and E₂ levels showed no significant changes in males, remaining at low levels throughout the reproductive cycle. The highest VTG levels in females and males were 1.6 mg ml^–1 and 124.87 ng ml^–1, respectively. These results indicate that the baseline level (normal level) in males was approximately 130 ng ml^–1 at most. We concluded that the threshold between normal and abnormal levels with a 10% risk rate was 150 ng ml^–1 in the wild male goby. Plasma VTG levels in males captured from Nagasaki Harbor were higher than the threshold in each reproductive developmental stage, indicating the possibility of EE pollution at this site. The biological standard baseline for VTG established in this study is useful for assessing EE pollution in natural waters.     

Common fragile site instability in normal cells: Lessons and perspectives

Mechanisms and events related to common fragile site (CFS) instability are well known in cancer cells. Here, we argue that normal cells remain an important experimental model to address questions related to CFS instability in the absence of alterations in cell cycle and DNA damage repair pathways, which are common features acquired in cancer. Furthermore, a major gap of knowledge concerns the stability of CFSs during gametogenesis. CFS instability in meiotic or postmeiotic stages of the germ cell line could generate chromosome deletions or large rearrangements. This in turn can lead to the functional loss of the several CFS‐associated genes with tumor suppressor function. Our hypothesis is that such mutations can potentially result in genetic predisposition to develop cancer. Indirect evidence for CFS instability in human germ cells has been provided by genomic investigations in family pedigrees associated with genetic disease. The issue of CFS instability in the germ cell line should represent one of the future efforts, and may take advantage of the existence of sequence and functional conservation of CFSs between rodents and humans.     

包头市2014—2016年中小学生常见病监测结果分析

目的了解内蒙古自治区包头市中小学生生长发育及常见病患病状况,客观地对学校卫生保健工作进行评价,为今后学校制定有效防治措施提供依据。方法对包头市中小学生开展年度健康体检,对视力低下、营养不良、肥胖、恒牙龋齿等常见病进行统计分析。结果 2014—2016年689 513名学生的监测结果显示,各类常见病患病率由高到低分别为视力低下37.22%、恒牙龋齿12.53%、肥胖8.03%和营养不良3.67%。从2014年、2015年到2016年的患病趋势分析,营养不良呈递减趋势(P <0.05),肥胖2014年和2015年变化趋势不明显(P> 0.05),2016年呈递增趋势(P <0.05),恒牙龋齿与视力低下呈递增趋势(P <0.05);从小学到中学的检出趋势分析,营养不良、肥胖、视力低下呈递增趋势(P <0.05),恒牙龋齿呈递减趋势(P <0.05)。结论包头市中小学生常见病患病率仍较高,应重点加强对中小学生视力不良、龋齿等防治工作,对中小学生普遍存在的健康问题,急需进行干预。