Control of Switching Modes and Conductance Quantization in Oxygen Engineered HfOx based Memristive Devices

Hafnium oxide (HfO_x)‐based memristive devices have tremendous potential as nonvolatile resistive random access memory (RRAM) and in neuromorphic electronics. Despite its seemingly simple two‐terminal structure, a myriad of RRAM devices reported in the rapidly growing literature exhibit rather complex resistive switching behaviors. Using Pt/HfO_x/TiN‐based metal–insulator–metal structures as model systems, it is shown that a well‐controlled oxygen stoichiometry governs the filament formation and the occurrence of multiple switching modes. The oxygen vacancy concentration is found to be the key factor in manipulating the balance between electric field and Joule heating during formation, rupture (reset), and reformation (set) of the conductive filaments in the dielectric. In addition, the engineering of oxygen vacancies stabilizes atomic size filament constrictions exhibiting integer and half‐integer conductance quantization at room temperature during set and reset. Identifying the materials conditions of different switching modes and conductance quantization contributes to a unified switching model correlating structural and functional properties of RRAM materials. The possibility to engineer the oxygen stoichiometry in HfO_x will allow creating quantum point contacts with multiple conductance quanta as a first step toward multilevel memristive quantum devices.     

Efficacité d'une intervention de groupe auprès d'hommes agressés sexuellement dans leur enfance.

The purpose of this research was to evaluate the effects of a group intervention intended for men victims of childhood sexual abuse (CSA). A quasi-experimental design was used to compare 23 men who took part in the group intervention against 13 men who suffered CSA but who received no service relative to this victimization. Data was collected through a self-administered questionnaire, which comprised various sections, including: 1) one on the participants' sociodemographic and CSA characteristics; 2) a posttraumatic stress symptoms scale; 3) a psychological distress index; 4) a self-esteem measure; and 5) a measure of the feeling of loneliness. The results demonstrate that, compared with the men in the control group, the men who completed the group intervention improved significantly in terms of self-esteem and on the subscale measuring CSA-related traumatic symptoms. No inter-group difference emerged concerning psychological distress, posttraumatic stress, and feeling of loneliness. Despite certain methodological limitations (including the non-random distribution of subjects into groups and the small size of the samples), the use of a quasi-experimental control-group design and of validated standardized measures (including one for posttraumatic stress disorder) lends strength and credence to the study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Housing Deprivation and Health: A Longitudinal Analysis

While there is a longitudinal literature that considers the impact of poor socio-economic circumstances upon health, the more specific impact of poor housing upon health is much less frequently studied longitudinally. This paper draws on the National Child Development Study to examine the impact upon health of poor housing through the life course. The analysis takes the novel approach of constructing a composite severity of ill health measure to act as the dependent variable. Poor housing is operationalised through a housing deprivation index calculated for each sweep of the NCDS. The index of multiple housing deprivation goes beyond traditional concerns with the quality and amenity of a dwelling to incorporate key subjective factors such as satisfaction with dwelling or residential area: these subjective factors play a particularly important role in the index. The key result is that, even when other relevant factors are allowed for, the NCDS data suggest that experience of both current and past poor housing is significantly associated with greater likelihood of ill health. Moreover, for those who are living in non-deprived housing conditions in adulthood, ill health is more likely among those who experienced housing deprivation in earlier life than among those who did not. Thus, history matters. The analysis also highlights the increasing inadequacy of conventional measures of housing deprivation.     

Executive coaching: It works!

Outcomes of this empirical study demonstrated that executive coaching is an effective method of leadership development. One hundred fourteen executives and 42 coaches were surveyed using instruments designed to gather both quantitative and qualitative data. Results indicated that executive change occurred in 5 areas: people management, relationships with managers, goal setting and prioritization, engagement and productivity, and dialogue and communication. This study also highlights the importance of coach selection, executive commitment to behavioral change, and the role of good program and environmental support. The success of this coaching program also suggests that investment in well-designed and implemented programs can contribute to leadership development and the retention of talent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Biochemical and sensorial evaluation of intact and boned broiler breast meat tenderness during ageing

Meat tenderness is the main characteristic demanded by consumers and is affected by rigor mortis development and proteolysis activities, both of which occur during carcass refrigeration. In this work, we demonstrate that broiler breast fillet tenderness can be further increased and its extension depends on whether or not meat is excised from the carcass. Post-harvest samples taken from 0 to 72 h after slaughtering and kept refrigerated at 2 ± 2 °C were evaluated for tenderness by myofibrillar fragmentation index determination, shear force analysis and sensorial testing. The 24 h post-harvested intact samples were 30.6% more tender than excised samples and 41.7% more tender than control samples (p ? 0.05). The myofibrillar fragments index was 13.2% higher in intact samples than in deboned fillet (p ? 0.05) and a sensory test showed that the 24 h intact samples were of major acceptability. Our results demonstrated that tenderness was best achieved with intact breast fillet samples stored at 2 ± 2 °C for 24 h.     

Impacts of distributors and group purchasing organizations on hospital efficiency and profitability: a bilateral data envelopment analysis model

Total health care expenses have risen significantly in the United States. There are many factors and variables that can impact hospital operating efficiencies. Among them, engaging a distributor or group purchasing organization (GPO) is one method to influence efficiency throughout the entire supply chain. This research investigates the impact of distributors and GPOs on hospital efficiency and profitability. The data from the 2015 American Hospital Association (AHA) Annual Hospital Survey of which 6251 hospitals participated are used. These hospitals were separated by those who purchased supplies through a distributor and those who did not. Likewise, the same was performed for those hospitals that used GPO and those that did not. This study employs DEA-Solver software to develop four types of bilateral DEA models. The results of the DEA model use a ranking variable (rank sum) to rank the variables within the two groups (distributor and no distributor) to determine if there is a significant difference between distributor and nondistributor. The same is performed for GPO and non-GPO. We examined the impact of the several control variables on hospital efficiency for distributors and GPOs. Results indicate that the control variables (region, education, profit/nonprofit, government/nongovernment, and system/nonsystem) made a significant difference for hospitals that used a distributor and a GPO. Lessons and implications are discussed for future research issues, such as quality of patient care and a frontier production function.     

Is correspondence reflected in the author position? A bibliometric study of the relation between corresponding author and byline position

Bibliometric indicators are increasingly used to fund and evaluate scientific research. Since the number of authors in a paper and the number of has increased it is difficult to determine the individual contribution of authors. Suggested approaches include the study of author position or the corresponding author. Our findings show that the corresponding author is most likely to appear first and then last in the byline. The results are dependent on number of authors in a paper and national differences exist. This underscores the need to take into account both the number of authors on a paper and their position in the byline to be accurate when measuring author contribution.     

Invited review: Disentangling residual feed intake—Insights and approaches to make it more fit for purpose in the modern context

Residual feed intake (RFI) is an increasingly used trait to analyze feed efficiency in livestock, and in some sectors such as dairy cattle, it is one of the most frequently used traits. Although the principle for calculating RFI is always the same (i.e., using the residual of a regression of intake on performance predictors), a wide range of models are found in the literature, with different predictors, different ways of considering intake, and more recently, different statistical approaches. Consequently, the results are not easily comparable from one study to another as they reflect different biological variabilities, and the relationship between the residual (i.e., RFI) and the underlying true efficiency also differs. In this review, the components of the RFI equation are explored with respect to the underlying biological processes. The aim of this decomposition is to provide a better understanding of which of the processes in this complex trait contribute significantly to the individual variability in efficiency. The intricacies associated with the residual term, as well as the energy sinks and the intake term, are broken down and discussed. Based on this exploration as well as on some recent literature, new forms of the RFI equation are proposed to better separate the efficiency terms from errors and inaccuracies. The review also considers the time period of measurement of RFI. This is a key consideration for the accuracy of the RFI estimation itself, and also for understanding the relationships between short-term efficiency, animal resilience, and long-term efficiency. As livestock production moves toward sustainable efficiency, these considerations are increasingly important to bring to bear in RFI estimations.