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1.

Our study investigates the relationship between technology innovation and human development in technologically advanced countries using data from quarterly observations from the last decade of the twentieth century to the first two decades of the twenty-first century. This objective of this study is to implement Quantile-on-Quantile regression (QQ) technique that as formulated by Sim and Zhou (J Bank Finance 55:1–8, 2015) and the renowned Granger-causality in quantiles as proposed by Troster (Econom Rev 37(8):850–866, 2018) examine the basic relationship between the given quantiles of technology innovation and their effects on the quantiles of human development. Therefore, the outcomes of this study explain the overall interdependence of technology innovation and affect the overall human development index. It is enumerated that the empirical results indicate that a significant positive relationship exists between technology innovation and human development in all selected technologically advanced countries, predominantly in both low and high tails. Moreover, the outcomes of Granger causality quantiles indicate a bi-directional fundamental relationship between these two variables in the dataset of all countries. The outcomes of the observations are extended to the recent findings on these two variables’ nexus and imply a differential impact on the technologically advanced countries. This causality guides us to offer some specific policy recommendations to each group of countries.

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2.
The use of robust measures helps to increase the precision of the estimators, especially for the estimation of extremely skewed distributions. In this article, a generalized ratio estimator is proposed by using some robust measures with single auxiliary variable under the adaptive cluster sampling (ACS) design. We have incorporated tri-mean (TM), mid-range (MR) and Hodges-Lehman (HL) of the auxiliary variable as robust measures together with some conventional measures. The expressions of bias and mean square error (MSE) of the proposed generalized ratio estimator are derived. Two types of numerical study have been conducted using artificial clustered population and real data application to examine the performance of the proposed estimator over the usual mean per unit estimator under simple random sampling (SRS). Related results of the simulation study show that the proposed estimators provide better estimation results on both real and artificial population over the competing estimators.  相似文献   
3.
The influence of neoliberalism on culture and subjectivity is well documented. This paper contributes to understanding of how neoliberal ideology enters into the production of subjectivity. While subject formation takes place in multiple and contradictory ways and across multiple social sites, we focus on the increasingly popular media discourse of self-development, and examine it as a technology of neoliberal subjectification. Drawing on Foucauldian understandings, we analyze data from two different newspapers from two different national contexts, both of which are heavily influenced by neoliberalism. Based on our analysis, we detail four interrelated discourses—rationality, autonomy and responsibility, entrepreneurship, and positivity and self-confidence—demonstrating how these discourses constitute the neoliberal subject in ways consonant with neoliberal governmentality. There is no observable resistance to subject positions offered within these discourses. Self-development discourse instills stronger individualism in society, while constraining collective identity, and thus provides social control and contributes to preserving status quo of neoliberal societies.  相似文献   
4.
We use a regression discontinuity design to study how academic probation affects outcomes and course‐taking behaviors at a large public university in the United States. Consistent with past work, students placed on probation improve their grade point average (GPA) in the subsequent semester. We document that part of this GPA improvement is attributable to strategic course‐taking, and there is significant heterogeneity in these behaviors across race. Non‐minority students placed on probation attempt fewer credits, easier courses, and are more likely to withdraw from courses in the following term. In contrast, underrepresented minorities exhibit few of these behaviors, consistent with past work that suggests black and Hispanic students are less likely to possess helpful institutional knowledge and use available support systems such as academic counseling. (JEL I20, I23)  相似文献   
5.
We study the problem of locating facilities on the nodes of a network to maximize the expected demand serviced. The edges of the input graph are subject to random failure due to a disruptive event. We consider a special type of failure correlation. The edge dependency model assumes that the failure of a more reliable edge implies the failure of all less reliable ones. Under this dependency model called Linear Reliability Order (LRO) we give two polynomial time exact algorithms. When two distinct LRO’s exist, we prove the total unimodularity of a linear programming formulation. In addition, we show that minimizing the sum of facility opening costs and expected cost of unserviced demand under two orderings reduces to a matching problem. We prove NP-hardness of the three orderings case and show that the problem with an arbitrary number of orderings generalizes the deterministic maximum coverage problem. When a demand point can be covered only if a facility exists within a distance limit, we show that the problem is NP-hard even for a single ordering.  相似文献   
6.
For about 10 years now in France, doctors in occupational medicine have been using the category “suffering at work” to refer to what they consider to be new pathologies at the workplace. This category's diffusion in industrial medicine reveals the influence of a current in psychology (the “psychodynamics of work”) on these doctors. A qualitative study carried out with workplace doctors shows how a large percentage of them have appropriated this category. An active — and activist — fraction has wielded it to defend a new conception of industrial medicine's role, which centered around clinical practices, should pay more attention to workers’ subjective sense of suffering. In a context where the institutional prospects of industrial medicine are a cause of concern and where feelings of a lack of esteem have been revived in a profession that, since its origins, has been looking for legitimacy, the category of work-related suffering enables these doctors to win new territory and breathing room by transforming their line of work.  相似文献   
7.

Research in urban ecology is growing rapidly in response to the exponential growth of the urban environment. However, few studies have focused on tropical megacities, and on the interplay between predators’ habitat selection and human socio-economic aspects, which may mediate their resilience and coexistence with humans. We examined mechanisms of breeding habitat selection by a synanthropic raptor, the Black Kite Milvus migrans, in Delhi (India) where kites mainly subsist on: (1) human refuse and its associated prey-fauna, and (2) ritualised feeding of kites, particularly practised by Muslims. We used mixed effects models to test the effect of urban habitat configuration and human practices on habitat selection, site occupancy and breeding success. Kite habitat decisions, territory occupancy and breeding success were tightly enmeshed with human activities: kites preferred areas with high human density, poor waste management and a road configuration that facilitated better access to resources provided by humans, in particular to Muslim colonies that provided ritual subsidies. Furthermore, kites bred at ‘clean’ sites with less human refuse only when close to Muslim colonies, suggesting that the proximity to ritual-feeding sites modulated the suitability of other habitats. Rather than a nuisance to avoid, as previously portrayed, humans were a keenly-targeted foraging resource, which tied a predator’s distribution to human activities, politics, history, socio-economics and urban planning at multiple spatio-temporal scales. Many synurbic species may exploit humans in more subtle and direct ways than was previously assumed, but uncovering them will require greater integration of human socio-cultural estimates in urban ecological research.

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8.

In this paper, an extension of the minimum cost flow problem is considered in which multiple incommensurate weights are associated with each arc. In the minimum cost flow problem, flow is sent over the arcs of a graph from source nodes to sink nodes. The goal is to select a subgraph with minimum associated costs for routing the flow. The problem is tractable when a single weight is given on each arc. However, in many real-world applications, several weights are needed to describe the features of arcs, including transit cost, arrival time, delay, profit, security, reliability, deterioration, and safety. In this case, finding an optimal solution becomes difficult. We propose a heuristic algorithm for this purpose. First, we compute the relative efficiency of the arcs by using data envelopment analysis techniques. We then determine a subgraph with efficient arcs using a linear programming model, where the objective function is based on the relative efficiency of the arcs. The flow obtained satisfies the arc capacity constraints and the integrality property. Our proposed algorithm has polynomial runtime and is evaluated in rigorous experiments.

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9.
Motivated by a real world application, we study the multiple knapsack problem with assignment restrictions (MKAR). We are given a set of items, each with a positive real weight, and a set of knapsacks, each with a positive real capacity. In addition, for each item a set of knapsacks that can hold that item is specified. In a feasible assignment of items to knapsacks, each item is assigned to at most one knapsack, assignment restrictions are satisfied, and knapsack capacities are not exceeded. We consider the objectives of maximizing assigned weight and minimizing utilized capacity.We focus on obtaining approximate solutions in polynomial computational time. We show that simple greedy approaches yield 1/3-approximation algorithms for the objective of maximizing assigned weight. We give two different 1/2-approximation algorithms: the first one solves single knapsack problems successively and the second one is based on rounding the LP relaxation solution. For the bicriteria problem of minimizing utilized capacity subject to a minimum requirement on assigned weight, we give an (1/3,2)-approximation algorithm.  相似文献   
10.
Background: Late-onset hypogonadism (LOH) presents with low serum testosterone (TT) levels and sexual and nonsexual symptoms. Erectile dysfunction affects a man’s self-esteem and as a result partner relationship and quality of life.

Objectives: To investigate the andrological clinical profile outcomes of testosterone therapy (TTh) in men (n?=?88) with symptomatic LOH complaints and symptoms.

Main outcome measures: Erectile function was assessed using the International Index of Erectile Function-5 questionnaire at baseline and at 6 and 12 months of TTh. In addition, penile length was measured at baseline and 12 months. We also evaluated nocturnal penile tumescence (NPT, using RigiScan) and blood flow of cavernous arteries (penile Doppler ultrasonography) at baseline and 12 months of TT.

Materials and methods: Eighty-eight LOH men (Mage 51.1 years) with erectile dysfunction, all with serum TT?<10.4?nmol/L before TTh. Patients received intramuscular long-acting testosterone undecanoate for 12 months.

Results: Following TTh, in all patients, serum TT levels were restored within 3 months to normal levels. Compared with baseline values, erectile function significantly improved at 6 (mean score increase 1.95) and 12 months (mean score increase 2.16). No significant changes in penile length were observed. NPT significantly improved at 12 months in terms of both the frequency (mean increase 1.27 times) and duration of rigidity (mean increase 5.12?min). As regards the blood flow of the cavernous arteries, we observed a significant improvement (decrease of 1.16?cm/s) and end diastolic velocity of the penile arteries.

Conclusion: TTh in men with LOH resulted in improvement of the erectile function, NPT, and to some extent the blood flow of the cavernous arteries.  相似文献   
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