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101.
通过对黄龙洞年内不同季节定点测定,同时与对旅游影响还不大的龙王洞对比测定,作者发现黄龙滑滑内空气CO2浓度的明显变化主要受客流量的影响。旅游旺季和黄金周客流量急剧增长带来的洞内空气CO2浓度大幅度增长,有利于岩溶作用,但洞内黑暗、高湿、低温的生态环境,对洞内工作人员身体健康有害。洞穴内岩溶景观的变化,主要受漫长的自然岩溶过程的影响,与洞内开发旅游活动的关系不大,但与洞顶山地植被保护状况有密切关系。  相似文献   
102.
This paper uses primary data to analyze the institutions and informal markets that govern groundwater allocation in a sugarcane-cultivating village in North India. We find that, in contrast to earlier literature, the observed water trades result in efficient water allocation across farms. We interpret this and other stylized facts in terms of a social contract using a simple bargaining model with limited inter-player transfers. Poor functioning of the power sector leads to reduced pumping and a water supply constraint. Simulations show that power supply reform can significantly increase farm yields, and be financed out of increased farm profits.  相似文献   
103.
This paper provides a comprehensive examination of asymmetry in US state‐level business cycles. We consider two different types of asymmetry in the adjustment process of a stationary time series: deepness and steepness. The data used in the study are a comparable set of state‐level coincident indexes (SCIs) developed by the Federal Reserve Bank of Philadelphia. Specifically, results from using the momentum‐threshold autoregressive model provide evidence of asymmetry in the growth rate of 23 SCIs as well as the equivalent national coincident index.  相似文献   
104.
以中国企业为研究对象,运用复合案例研究方法分析与构建了科学型企业商业模式概念模型,分离出科学平台和价值平台两个独特要素,进而构建以科学平台-价值平台互动为核心的P2P商业模式运作模型,并根据不同类型科学型企业,分析模型的有效性、适用性以及模型在不同类型科学型企业中的共性与差异,最后总结出科学型企业商业模式特点及企业管理对策。  相似文献   
105.
Aims: To model direct medical costs associated with reductions in cardiovascular disease (CVD) events in T2DM patients reported in the CANVAS and EMPA-REG trials, which assessed the cardiovascular safety of canagliflozin and empagliflozin, respectively.

Materials and methods: Costs were modeled from a US managed care organization (MCO) perspective for the CVD outcomes included in both trials: three-point major adverse cardiovascular event (MACE) and its components (cardiovascular-related death, nonfatal myocardial infarction, nonfatal stroke), as well as heart failure requiring hospitalization. The rate of CVD events averted (difference between study drug and placebo) was projected to the portion of an MCO T2DM population matching the respective trial’s inclusion criteria. A targeted literature search for paid amounts directly associated with each CVD event provided the unit costs, which were applied to the projected number of events averted, to calculate costs avoided per member per year (PMPY). One-way sensitivity analyses were performed on events averted, unit costs, and percentages of trial-applicable patients.

Results: Based on three-point MACE events averted, costs avoided PMPY of $6.17 (range: $1.27–$10.94) for CANVAS and $2.75 ($0.19–$4.83) for EMPA-REG were estimated. Costs avoided for individual components of MACE ranged from $0.77 to $3.84 PMPY for CANVAS and from -$0.97 (additional costs) to $1.54 for EMPA-REG. PMPY costs avoided for heart failure were $2.72 for CANVAS and $1.32 for EMPA-REG.

Limitations and conclusions: Models assumed independent, non-recurrent outcomes and were restricted to medical costs directly associated with the trial-reported events. The reductions in CVD events in T2DM patients reported for both CANVAS and EMPA-REG project to a positive cost avoidance for these events in an MCO population. The analysis did not include an assessment of the impact on total cost, as the costs associated with adverse events, drug utilization or other clinical outcomes were not examined.  相似文献   

106.
Aims: Examine healthcare costs across chronic kidney disease (CKD) stages for US patients with type 2 diabetes (T2D).

Materials and methods: IQVIA Real World Data Adjudicated Claims linked electronic medical records and insurance claims from January 1, 2012 through March 31, 2017 were used for this retrospective study. Adults diagnosed with T2D and comorbid CKD were included. General linear models incorporating splines were constructed, and information from these regressions were used to inform the relationship between medical costs and CKD. Multivariable analyses controlled for patient characteristics, vital signs, general health, prior medication use, prior visit to specialists, index A1c, and year of index date.

Results: There were 6,645 individuals who met the study criteria. Results generally indicate sharp increases in annual total medical costs and non-drug medical costs in the 1?year post-period for patients with Stage 4 or 5 CKD (estimated glomerular filtration rate [eGFR]?≤?30?mL/min/1.73 m2) with each 1 point reduction in eGFR from 30 associated with an increase of $1,870 in all-cause total medical costs (p?<?0.0001) and $1,805 of all-cause non-drug medical costs (p?<?0.0001). Similarly, each point decline below 30?mL/min was associated annual cost increases of $1,701 for CKD-related total medical costs, $1,695 for CKD-related non-drug medical costs, $173 for diabetes-related medical costs, and $187 for diabetes-related non-drug medical costs (all p?<?0.0001).

Limitations: The investigation included only patients with medical insurance and laboratory test results, and results may not be generalizable to all T2D patients with CKD. The methodology allowed us to determine associations, not causation, and potential confounders, such as duration of diabetes, diet, exercise, or social support, could not be assessed.

Conclusions: Results indicate there are sharp and significant increases in medical costs among T2D patients with Stage 4 and 5 CKD compared to those with earlier stages of CKD.  相似文献   
107.
This paper examines the effect of political institutions on fiscal redistribution for a country-level panel from 1960–2010. Using data on Gini coefficients before and after government intervention, we apply a measure of effective fiscal redistribution that reflects the effect of taxes and transfers on income inequality. Our findings clearly indicate that non-democratic regimes demonstrate significantly greater direct fiscal redistribution. Subsequently, we employ fiscal data in an attempt to enlighten this puzzling empirical finding. We find that dictatorial regimes rely more heavily on cash transfers that exhibit a direct impact on net inequality and consequently on the difference between market and net inequality (i.e., effective fiscal redistribution), whereas democratic regimes devote a larger amount of resources to public inputs (health and education) that may influence market inequality but not the difference between market and net inequality per se. We argue that the driving force behind the observed differences within the pattern on government spending and effective fiscal redistribution is that democratic institutions lead survival-oriented leaders to care more for the private market, and thus to follow policies that enhance the productivity of the whole economy.  相似文献   
108.
Abstract This study uses panel data on Canadian establishments to explore the relationship between the organization of work – in particular decentralization, information‐sharing, and incentive pay schemes – and innovation. Like other studies, ours finds a clear positive link between these factors. However, the data give strong indications that this relationship is not causal. We show that: (1) the correlation between workplace organization and innovation holds for information‐sharing but is much weaker for decentralized decision‐making or incentive pay programs, (2) controls for unobserved heterogeneity significantly weaken results, and (3) lagged variables give no clear evidence that organizational changes predate innovation.  相似文献   
109.
Abstract This paper studies the entry and tax regulation of oligopolistically competitive privately run casinos and government‐run casinos in a jurisdiction. We highlight three important external effects from casino‐style gambling: non‐casino income creation, social disorder costs, and cross‐border gambling. The laissez‐faire equilibrium need not be overcrowding compared with regulated or government‐run regimes. Entry regulation may lead to higher jurisdiction welfare than tax regulation. Government‐run casinos always operate on a larger scale and achieve higher welfare than other regimes, given the same number of casinos. With an endogenous fraction of external gamblers, a dispersed casino configuration yields higher welfare than a centralized one.  相似文献   
110.
This article analyzes the modelling of risk premia in CO2 allowances spot and futures prices, valid for compliance under the EU Emissions Trading Scheme (EU ETS). Similarly to electricity markets, a salient characteristic of CO2 allowances is that the theory of storage does not hold, as CO2 allowances only exist on the balance sheets of companies regulated by the scheme. The main result features positive time-varying risk premia in CO2 spot and futures prices, which are strictly higher for post-2012 contracts (€6–9/ton of CO2) than for Phase II contracts (€0–6/ton of CO2). Contrary to Benth et al.'s (2008) for electricity markets, a positive relationship between risk premia and time-to-maturity is found in the EU ETS. As for relative differences between CO2 futures and spot prices, CO2 futures traded between + 1% (December 2008 contract) and + 33% (December 2014 contract) above spot prices during February 2008–April 2009. Contrary to Bessembinder and Lemmon (2002) for the electricity market, a positive relationship between risk premia and the variance/skewness of CO2 spot prices is found. The futures-spot bias to the EU ETS explains around 1–6% of the variance of CO2 futures premia.  相似文献   
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