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11.
Aims: To better understand the impact of the clinical course of multiple sclerosis (MS) and disability on employment, absenteeism, and related factors.

Materials and methods: This study included respondents to the North American Research Committee on Multiple Sclerosis Registry spring 2015 update survey who were US or Canadian residents, aged 18–65 years and reported having relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), or primary progressive MS (PPMS). The RRMS and SPMS participants were combined to form the relapsing-onset MS (RMS) group and compared with the PPMS group regarding employment status, absenteeism, and disability. Multivariable logistic regression was used to examine the relationship between employment-related outcomes and factors that may affect these relationships.

Results: Of the 8004 survey respondents, 5887 (73.6%) were 18–65 years of age. The PPMS group (n?=?344) had a higher proportion of males and older mean age at the time of the survey and at time of diagnosis than the RMS group (n?=?4829). Female sex, age, age at diagnosis, cognitive and hand function impairment, fatigue, higher disability levels, ≥3 comorbidities, and a diagnosis of PPMS were associated with not working. After adjustment for disability, the employed PPMS sub-group reported similar levels of absenteeism to the employed RMS sub-group.

Limitations: Limitations of the study include self-report of information and the possibility that participants may not fully represent the working-age MS population.

Conclusions: In MS, employment status and absenteeism are negatively affected by disability, cognitive impairment, and fatigue. These findings underscore the need for therapies that prevent disability progression and other symptoms that negatively affect productivity in persons with MS to enable them to persist in the workforce.  相似文献   
12.
13.
The COVID-19 pandemic has caused a crisis in the hotel industry worldwide, but few studies have suggested methods to retain customers. This study proposes hygiene management as a means to minimize the indirect damage from COVID-19 to the hotel industry. It identifies perceived hygiene attributes and explores their influence on hotel image, word of mouth, and revisit intentions. This study identifies and validates three types of perceived hygiene attributes through qualitative and quantitative methods. It uses structural equation modeling to validate hypotheses and concludes that there are significant relationships of influence between the proposed variables. This study provides important and meaningful insights into hotel image and customer behavior through perceived hygiene attributes.  相似文献   
14.
黑胚小麦病又被称为小麦黑点病,是一种在小麦胚或其他部位出现变色的病害。文章主要论述了我国在新形势下对黑胚小麦病的研究及其流行规律和病因,同时阐述了新疆粮油产品质量监督检验站在应对黑胚小麦病上的检验措施。  相似文献   
15.
We elaborate some complex stylized facts related to the Mexican economy. The analyzed period runs from 1960 to 2013 with selected subperiods. Our main findings are: 1) there are involuntary idle capacities in the manufacturing industries; 2) the growth of the Mexican economy is not balanced but unbalanced; 3) there is an inflation-free environment. This fact is consistent with the previous ones; 4) there is a mixed of efficient and inefficient sequences of investment; 5) the stimulus of manufacturing exports on macroeconomic performance has been offset by its imports; 6) the deficits in manufacturing balance and in the current account have been financed without difficulty. Of course, this financing capacity constitutes a second best condition; 7) according to a backward linkages analysis, the towing capacity of manufacturing sector over the Mexican economy would be a larger one if the manufacturing imports penetration had not been so intense since the trade liberalization; and 8) the size of the positive effect of the manufacturing sector on the economy and on the non-manufacturing sectors diminished since the early eighties. Our complex stylized facts highlight the need for an upgrading of the current economic policies.  相似文献   
16.
Complex network theory is a framework increasingly used in the study of air transport networks, thanks to its ability to describe the structures created by networks of flights, and their influence in dynamical processes such as delay propagation. While many works consider only a fraction of the network, created by major airports or airlines, for example, it is not clear if and how such sampling process bias the observed structures and processes. In this contribution, we tackle this problem by studying how some observed topological metrics depend on the way the network is reconstructed, i.e. on the rules used to sample nodes and connections. Both structural and simple dynamical properties are considered, for eight major air networks and different source datasets. Results indicate that using a subset of airports strongly distorts our perception of the network, even when just small ones are discarded; at the same time, considering a subset of airlines yields a better and more stable representation. This allows us to provide some general guidelines on the way airports and connections should be sampled.  相似文献   
17.
Abstract

Objective:

This study assessed the long-term cost effectiveness of rosuvastatin therapy compared with placebo in reducing the incidence of major cardiovascular (CVD) events and mortality.

Methods:

A probabilistic Monte Carlo simulation model estimated long-term cost effectiveness of rosuvastatin therapy (20?mg daily) for the prevention of CVD mortality and morbidity. The model included three stages: (1) CVD prevention simulating the 4 years of the JUPITER trial, (2) initial CVD prevention beyond the trial, and (3) subsequent CVD event prevention. A US payer perspective was assessed reflecting direct medical costs, and up to a lifetime horizon. Sensitivity analyses tested the robustness of the model estimates.

Results:

For a hypothetical cohort of 100,000 patients at moderate and high risk of CVD events based on Framingham risk of ≥10%, estimated quality-adjusted life-years (QALYs) gained with rosuvastatin therapy compared with placebo was 33,480 over a lifetime horizon, and 25,380 and 9916 over 20-year and 10-year horizons, respectively. Approximately 12,073 events were avoided over the lifetime; 6,146 non-fatal MIs, 2905 non-fatal strokes, and 4030 CVD deaths avoided. Estimated incremental cost-effectiveness ratio (ICER) for cost per QALY was $7062 (lifetime), $10,743 (20-year horizon), and $44,466 (10-year horizon). For a hypothetical cohort similar to the overall JUPITER population, the cost per QALY ICER was $11,025 for the lifetime and $60,112 for a 10-year horizon.

Limitations:

The cost-effectiveness comparison of rosuvastatin 20?mg was against no active treatment (as opposed to an alternative statin) due to lack of comparative cardiovascular morbidity and mortality risk reduction data for other statins in a population similar to the JUPITER trial population. The analysis was conducted from the payer perspective and lack of inclusion of indirect costs limit interpretability of results from a societal perspective.

Conclusions:

Treatment with rosuvastatin 20?mg daily, is a cost-effective treatment alternative to no treatment in patients at a higher risk (Framingham risk ≥10%) of CVD.  相似文献   
18.
With the continuous development of the Internet and information technology, online shopping has become a popular purchase mode. The in-depth analysis of consumer decision-making in online shopping is an important issue. Our purpose is to study how the factors of the shopping web pages corporately affect online purchase decisions and determine which are the core factors that affect consumer purchase decisions. We screen the influencing factors on the shopping webpage and deploy e-commerce network evolution based on various weight combinations of these factors to generate sales distributions of online products. By comparing these simulated sales distributions to the real data, the optimal weight of each factor is obtained. The results show that sales volume and the number of high-quality negative comments are the most important factors influencing consumers' decision-making, the number of comments and the number of comments with pictures are relatively minor factors, store type and video presentation of the products have the least impact. The optimal simulated sales distribution is very close to the real case and verifies that the introduced network evolution technology is applicable. The proposed model can be used as a uniform evaluation platform for correlational study, which is an important link in the purchase research chain.  相似文献   
19.
The objective of this article is to analyze the domestic and international effects of a hypothetical foot‐and‐mouth disease (FMD) outbreak in the Mexican cattle industry. A discrete time dynamic optimization model of the Mexican cattle sector is specified, and linked to domestic and international markets. Economic consequences of FMD outbreaks are simulated over time and under different scenarios. Specific findings and general policy recommendations are provided. The study reports a range of outbreaks from localized to large scale and suggests that changes in economic surplus due to FMD range from a positive net gain of $0.89 to $1.6 billion to a net loss of about $67 billion, depending on the specific mitigation strategy and outbreak scenario.  相似文献   
20.
在突发事件应急管理过程中,科技研发支撑作用十分关键,亟需建立突发公共卫生事件科研应急体系长效运行机制。基于科技研发应急体系的复杂性、适应性特征,从主体属性和体系架构两个层面入手,分析重大突发公共卫生事件科技研发应急体系的复杂适应系统特征,运用复杂适应系统理论模型和动态闭环螺旋模型,研究重大突发公共卫生事件科技研发应急体系运行机制。研究发现,重大突发公共卫生事件背景下,科技研发应急体系具有复杂适应系统的7个基本特征,是典型的复杂适应系统;科技研发应急体系中,科研攻关专家组、诊疗医院、科技部门等科研主体具有各自内部模型,并通过6大标识进行聚集;科技研发应急体系存在事件—需求引导、主体协同、资源交互、成果转化机制。同时,新冠病毒肺炎疫情应对实践表明,疫情防控救治进程中科技研发应急体系存在并遵循上述运行机制。  相似文献   
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