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1.
The aim of this paper is to obtain new sharp inequalities for a large family of topological indices, including the second variable Zagreb index \(M_2^{\alpha }\), and to characterize the set of extremal graphs with respect to them. Our main results provide lower bounds on this family of topological indices involving just the minimum and the maximum degree of the graph. These inequalities are new even for the Randi?, the second Zagreb and the modified Zagreb indices.  相似文献   
2.
Production Planning and Control (PPC) has been one of the primary publishing outlets for operations management research for nearly three decades. This paper presents bibliometric analysis of the journal from its inception through 2016. PPC was analysed from six different perspectives to provide reliable and in-depth information about the journal’s performance and development. The analysis considered the development of the journal itself, the countries of contributing authors, authors’ academic and practitioner organisation affiliations, the top publishing and most cited authors, the most cited articles, and finally the topics of published papers through analysis of titles, keywords and abstracts. It was found that the journal is considered an outlet for both practice and academic research, reflecting changes over time in the landscape of operations management.  相似文献   
3.

Background

The rates of breastfeeding worldwide are slowly improving since 1996. Europe is still trailing behind the global breastfeeding incidence and prevalence rates. Thus, breastfeeding promotion, protection, prolongation and support have become an important challenge as breastfeeding sharply decreases in the first six months of life.

Objectives

The aim of this project is to determine, assess and identify the real impact of breastfeeding support networks in Murcia (Spain).

Methods

After searching unsuccessfully for a validated questionnaire, a specific one was developed and validated for measuring the impact of formal and informal support networks through five dimensions: satisfaction, consultation, experience, problems and support. The questionnaire was provided to 500 mothers with experience in breastfeeding, who brought their children to baby paediatricians between 2 June and 27 November 2014. Upon completion of the survey and fieldwork, a detailed statistical analysis was conducted.

Results

The degree of satisfaction perceived by the users of the services of support breastfeeding networks is remarkable. In addition, mothers who clarified their doubts and discussed their problems with health professionals and/or breastfeeding support networks were more likely to breastfeed for a longer duration compared to those who did not (p = 0.005). Furthermore, mothers who sought support in breastfeeding are more likely to breastfeed for more than 6 months (p < 0.0005).

Conclusion

Based on this information, we conclude that breastfeeding support networks have a positive influence in the duration of a women’s decision to breastfeed.  相似文献   
4.
A method is proposed in this paper to assess the local influence of minor perturbations for the Sharpe model when the normal distribution is replaced by normal/independent (NI) distributions. The family of NI distributions is an attractive class of symmetric heavy-tailed densities that includes as special cases the normal, t-Student, slash, and the contaminated normal distributions. Since the returns of the market are not observable, the statistical analysis is carried out in the context of an errors-in-variables model. An influence analysis for detecting influential observations (atypical returns) is developed to investigate the sensitivity of the maximum likelihood estimators. Diagnostic measures are obtained based on the conditional expectation of the complete-data log-likelihood function. The results are illustrated by using a set of shares of companies traded in the Chilean stock market.  相似文献   
5.
Abstract

This study analysed the influence of praise and criticism on moral pride (the pride we feel when we believe we have done something morally good) and guilt. Ninety-two adolescents (age: M = 15.17, SD = 0.43; 44.6% girls, 55.4% boys) completed a questionnaire which outlined 10 scenarios based on combinations of three variables: the moral nature of the action (positive/negative); praise, criticism or the absence of either; and the source (parents/peers). Participants were asked to indicate the intensity with which they would feel pride and guilt (seven-point scale). Praise of positive actions increased pride. Interestingly, criticism of positive actions reduced pride and increased guilt, while praise of negative actions reduced guilt and increased pride. No differences were found between the pride felt after a criticized positive action and that felt after a praised negative action. A parallel effect was not, however, observed for guilt. These results reveal the strong, sometimes pernicious, influence of praise and criticism on guilt and pride and, even more, the need for praise by others in the experience of moral pride.  相似文献   
6.

We analyze cooperation of individuals in a family context, using a Public Good game. In a lab experiment, 165 individuals from 55 three-generation families (youth, parent, and grandparent) play a repeated Public Good game in three different treatments: one in which three members of the same family play each other (family), a second with the youth and two non-family members, while preserving the previous generational structure (inter-generational), and a third in which three randomly-selected players play each other (random). We find that all the age groups cooperate more when playing with relatives, indicating that family ties may have a positive relationship to contributions to the Public Good. We also find that this trend is more evident for the youths and the parents than for the grandparents. Furthermore, young individuals tend to cooperate less than older generations, especially in non-family treatments. Our results serve as evidence of the relationship between family ties and inter-generational cooperative behaviors.

  相似文献   
7.
Not only ETO (Engineering to Order), but even serial production industry should know how to deal with projects and their schedule: plant commissioning, shutdown, introducing new products and similar circumstances should be managed with adequate planning and resource allocation techniques to create a schedule useful in decision making during the execution. The current complex reality, with evolving technologies and fierce pressure to reach the market as soon as possible, pushes the project managers to use more advanced techniques than waterfall planning, such as agile or lean. It also requires them to take a holistic view and manage concurrent tasks in complex projects. The contributions of this paper are two: the proposal to control specific parallel groups of waterfall activities under uncertain environments, which can lead to iterations and reworks, as a single concurrent Activity Managed by Kanban Methods (AMKM). This activity can be subsequently embedded into traditional scheduling approaches as CPM-PERT. The second contribution is the feasibility of its application in industrial environments due to the affordability of simulation software. Two use cases are shown as evidence. It is not a disruptive proposal, but a kaizen action based on very mature technologies. Finally, it is suggested some improvements to be implemented in Project Management Software due to this ‘kaizen’ proposal.  相似文献   
8.
In Europe, countries following the traditional Mediterranean Diet (MeDi), particularly Southern European countries, have lower prostate cancer (PCa) incidence and mortality compared to other European regions. In the present study, we investigated the association between the MeDi and the relative risk of PCa and tumor aggressiveness in a Spanish population. Among individual score components, it has been found that subjects with PCa were less likely to consume olive oil as the main culinary fat, vegetables, fruits and fish than those without. However, these differences were not statistically significative. A high intake of fruit, vegetables and cooked tomato sauce Mediterranean style (sofrito) was related to less PCa aggressiveness. Results showed that there are no differences in the score of adherence to the Mediterranean dietary patterns between cases and controls, with mean values of 8.37?±?1.80 and 8.25?±?2.48, respectively. However, MeDi was associated with lower PCa agressiveness according to Gleason score. Hence, relations between Mediterranean dietary patterns and PCa are still inconclusive and merit further investigations. Further large-scale studies are required to clarify the effect of MeDi on prostate health, in order to establish the role of this diet in the prevention of PCa.  相似文献   
9.
10.
This article studies the voters of DENK, the first immigrant party to gain seats in a national parliament. It builds further on the existing literature on how immigrants and people from immigrant descent vote in Western European countries. From the literature we derive seven expectations about the kind of voters that are likely to vote for an immigrant party in terms of their political cynicism, attitudes towards economic, globalisation and moral issues. We find that DENK voters are younger Muslims, who have conservative views on moral matters, cynical attitudes towards politics, right-wing views on economic matters and progressive views on issues that pertain to the globalisation dimension, such as immigration, integration and Islam and in particular discrimination. This article uses VAA data to construct a matched sample that in terms of key variables is representative for voters with and without a migration background.  相似文献   
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