bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developmental and reproductive characteristics of beef heifers classified by number of estrous cycles experienced by start of first breeding
Authors: Roberts Andrew J , Ketchum Jaclyn N , Funston Richard N 
Published: November 2018

Abstract
A retrospective analysis was conducted to evaluate the effect of number of estrous cycles exhibited before breeding on growth and reproductive performance of replacement beef heifers fed ad-libitum or restricted by 20% less than ad-libitum during postweaning development over a 9-yr period. Progesterone concentration in blood samples collected at 9- to 11-d intervals were used to assign heifers into groups by number of estrous cycles exhibited before the start of breeding: 0 (nonpubertal; n = 395), 1 (n = 205), 2 (n = 211), 3 (n = 116), or &gt;3 (n = 249). Heifers (P &lt; 0.01) in the 0 cycle group were born 6 d later than the 1, 2, or 3 cycle groups, which were born 4 d later (P &lt; 0.01) than the &gt;3 cycle group. Weight of heifers at birth decreased (P &lt; 0.05) as the number of cycles increased. Weaning weight and ultrasound measures of loin area and fat thickness over the loin at 1 yr age increased as the number of cycles increased (P &lt; 0.01). Postwean weight gain, hip height at 1 yr age, and weights from the start of breeding through precalving increased with cycle numbers in a quadratic fashion (P &lt; 0.02) and were greater (P &lt; 0.05) in ad-libitum than restricted-fed heifers. Pregnancy rate in the 0 cycle group was lower (84%; P &lt; 0.05) than the 1 (90%) or &gt;3 (94%) estrous cycles groups and tended to differ (P &lt; 0.1) from the 2 (88%) and 3 (89%) estrous cycle groups. Interval from the start of breeding to calving was 3 to 5 d longer (P &lt; 0.05) for the 0 cycle group (300 ± 1 d) than other groups. Proportion of heifers calving in the first 21 d was less (P &lt; 0.05) in the 0 or 1 cycle groups than other groups. Pregnancy rates of 2-yr-old cows (n = 898) were lowest (P &lt; 0.05) for the 0 (73%) and 2 (79%) estrous cycle groups than the 1 (85%), 3 (90%), or &gt;3 (92%) estrous cycle groups. Restricted level of feeding during postweaning development resulted in greater (P &lt; 0.05) proportion of heifers in 0 cycle group and lower (P &lt; 0.05) proportion in &gt;3 cycle group, but reproductive performance was not influenced (P &gt; 0.1) by level of feeding or interaction of feeding and estrous cycle grouping. In summary, date of birth and rate of physical maturation (weight, height, and fat deposition) were associated with timing of puberty. Pregnancy rate was greater in heifers that exhibited estrus before the start of breeding, but did not improve from having more than one estrous cycle. Proportion conceiving early was greater for heifers having two or more cycles before breeding.
Force inference predicts local and tissue-scale stress patterns in epithelia
Authors: Kong W. , Loison O. , Shivakumar P. , Collinet C. , Lenne P.F. , Clément R. 
Published: November 2018

AbstractMorphogenesis relies on the active generation of forces, and the transmission of these forces to surrounding cells and tissues. Hence measuring forces directly in developing embryos is an essential task to study the mechanics of development. Among the experimental techniques that have emerged to measure forces in epithelial tissues, force inference is particularly appealing. Indeed it only requires a snapshot of the tissue, as it relies on the topology and geometry of cell contacts, assuming that forces are balanced at each vertex. However, establishing force inference as a reliable technique requires thorough validation in multiple conditions. Here we performed systematic comparisons of force inference with laser ablation experiments in three distinct Drosophila epithelia. We show that force inference accurately predicts single junction tensions, tension patterns in stereotyped groups of cells, and tissue-scale stress patterns, in wild type and mutant conditions. We emphasize its ability to capture the distribution of forces at different scales from a single image, which gives it a critical advantage over perturbative techniques such as laser ablation. Our results demonstrate that force inference is a reliable and efficient method to quantify the mechanics of epithelial tissues during morphogenesis.
Effects of 5-aza-2’-deoxycytidine on human osteoarthritic chondrocytes
Authors: Kadler Shirin , Vural Özlem , Reiners-Schramm Luzia , Lauster Roland , Rosowski Mark 
Published: November 2018

AbstractBackgroundGiven regenerative therapies, the utilization of primary human cells is desired and requested in the development of in vitro systems and disease models. After a few passages in vitro, all cells from the connective tissue end up in a similar fibroblastoid cell type marked by loss of the specific expression pattern. It is still under discussion whether different de-differentiated mesenchymal cells have similar or identical differentiation capacities in vitro.MethodsChondrocytes isolated from patients with late-stage osteoarthritis were cultured for several passages until de-differentiation was completed. The mRNA level of cartilage markers was investigated, and the adipogenic, osteogenic and chondrogenic differentiation capacity was examined. By adding 5-aza-2’-deoxycytidine (5-aza-dC) to the media, the influence of DNA methylation on the differentiation capacity was analyzed.ResultsThe chondrocytes used in this work were not affected by the loss of specific gene expression upon cell culture. The mRNA levels of SOX5, SOX6, SOX9, aggrecan, and proteoglycan-4 remained unchanged. The underlying mechanisms of cartilage marker maintenance in osteoarthritic (OA) chondrocytes were investigated with a focus on the epigenetic modification by DNA methylation. The treatment of de-differentiated chondrocytes with the DNA methyltransferase inhibitor 5-aza-2’-deoxycytidine (5-aza-dC) displayed no appreciable impact on the observed maintenance of marker gene expression, while the chondrogenic differentiation capacity was compromised. On the other hand, the pre-cultivation with 5-aza-dC improved the osteogenesis and adipogenesis of OA chondrocytes. Contradictory to these effects, the DNA methylation levels were not reduced after treatment with 1 μM 5-aza-dC for four weeks.ConclusionChondrocytes isolated from late-stage osteoarthritic patients represents a reliable cell source for in vitro studies as wells as disease models since the chondrogenic differentiation potential remains. 5-aza-2’-deoxycytidine could not further improve their chondrogenic potential.
Biofilm/Persister/Stationary Phase Bacteria Cause More Severe Disease Than Log Phase Bacteria – II Infection with Persister Forms of Staphylococcus aureus Causes a Chronic Persistent Skin Infection with More Severe Lesion that Takes Longer to Heal and is not Eradicated by the Current Recommended Treatment in Mice
Authors: Yee Rebecca , Yuan Yuting , Brayton Cory , Leal Andreina Tarff , Feng Jie , Shi Wanliang , Behrens Ashley , Zhang Ying 
Published: November 2018

AbstractStaphylococcus aureus is an opportunistic pathogen that can cause persistent infections clinically. Treatment for chronic S. aureus infections ranges from at least one week to several months and such infections are prone to relapse likely due to the presence of persistent forms of bacteria such as persister cells. Persister cells, which are bacterial cells that become dormant under stress conditions, can be isolated in vitro but their clinical significance in in vivo infections are largely unclear. Here, we evaluated S. aureus persistent forms using stationary phase cultures and biofilm bacteria (enriched in persisters) in comparison with log phase cultures in terms of their ability to cause disease in a mouse skin infection model. Surprisingly, we found that infection of mice with stationary phase cultures and biofilm bacteria produced a more severe chronic skin infection with more pronounced lesions which took longer to heal than log phase (actively growing) cultures. After two week infection, the bacterial load and skin tissue pathology, as determined by hyperplasia, immune cell infiltration, and crust/lesion formation, of mice infected with the more persistent forms (e.g. stationary phase bacteria and biofilm bacteria) were greater than mice infected with log phase bacteria. Using our persistent infection mouse model, we showed that the clinically recommended treatment for recurrent S. aureus skin infection, doxycycline + rifampin, was not effective in eradicating the bacteria in the treatment study, despite reducing lesion sizes and pathology in infected mice. Analogous findings were also observed in a Caenorhabditis elegans model, where S.aureus stationary phase cultures caused a greater mortality than log phase culture as early as two days post-infection. Thus, we established a new model for chronic persistent infections using persister bacteria that could serve as a relevant model to evaluate therapeutic options for persistent infections in general. Our findings connect persisters with persistent infections, have implications for understanding disease pathogenesis, and are likely to be broadly valid for other pathogens.
Antiretroviral therapy is a major cause of tuberculosis decline in southern and eastern Africa
Authors: Dye Christopher , Williams Brian G. 
Published: November 2018

AbstractThe incidence of tuberculosis (TB) in southern and eastern Africa was driven sharply upwards during 1980s and 1990s by coinfection with Mycobacterium tuberculosis and the human immunodeficiency virus (HIV). Although drug treatments for TB infection (isoniazid preventive therapy) and disease (combinations of TB drugs) can reduce TB incidence if implemented effectively, we find that antiretroviral therapy (ART) given to people with HIV infection was strongly and systematically associated with the accelerated decline of TB in 12 of the worst affected African countries between 2003 and 2016. Inferring that ART was a significant cause of TB decline, ART prevented approximately 1.88 ± 0.23 million HIV-positive TB cases, or 15.7 ± 1.9 percent of the total number expected. There is no evidence that drug treatment of TB infection (IPT) or disease (combination chemotherapy) played more than a minor role in accelerating TB decline after 2003. In these 12 countries, over the period 2003–16, ART made a major contribution towards achieving international targets for the reduction of TB incidence.SignificanceTuberculosis (TB) is still the leading cause of death from a single infectious agent. To cut the TB incidence rate by 80% between 2015 and 2030, in line with the WHO End TB Strategy, demands a five-fold increase in the rate of decline worldwide, from 2% to 10%/year. We find that the reduction in TB incidence rate in 12 African countries, at up to 8%/year, is due mainly to the expanded provision of antiretroviral therapy (ART) to people living with HIV, rather than to improvements in the treatment of TB infection and disease. ART should remain central to TB control where rates of TB-HIV coinfection are high, but new efforts are needed to maximize the direct benefits of treating TB infection and disease.
Wheel-running exercise during adolescence may not convincingly impact cocaine conditioned place preference in male C57BL/6J mice
Authors: Lespine Louis-Ferdinand , Tirelli Ezio 
Published: November 2018

AbstractWheel-running in rodents can mitigate addiction-related effects of drugs of abuse like cocaine. However, experiments using conditioned place preference (CPP) are conflicting, warranting further studies. Our purpose was to test whether wheel-running during adolescence could impact the formation and long-term retention of CPP to cocaine in mice. Male C57BL/6J mice were individually housed either with (n=32) or without (n=32) a running wheel from the age of 35 days. Behavioral testing began 3 weeks after such housing, mice underwent a baseline session followed by 10 once-daily conditioning sessions receiving peritoneal injections of 10 mg/kg cocaine and saline on alternate days (n=16), control mice receiving saline every day (n=16). One and 21 days after the last conditioning session, they were tested for CPP. Both groups exhibited comparable well-marked cocaine-induced CPP in both post-conditioning tests resulting in a negligible interaction between housing and the pharmacological treatment (η²p < 0.01). These results, along with the discrepancy found in the literature, question the nature (and the robustness) of the effects that exercise induces on CPP to cocaine.
A mathematical model of calcium dynamics: Obesity and mitochondria-associated ER membranes
Authors: Han Jung Min , Periwal Vipul 
Published: November 2018

AbstractMultiple cellular organelles tightly orchestrate intracellular calcium (Ca2+) dynamics to regulate cellular activities and maintain homeostasis. The interplay between the endoplasmic reticulum (ER), a major store of intracellular Ca2+, and mitochondria, an important source of adenosine triphosphate (ATP), has been the subject of much research, as their dysfunctionality has been linked with metabolic diseases. Interestingly, through out the cell’s cytosolic domain, these two organelles share common microdomains called mitochondria-associated ER membranes (MAMs), where their membranes are in close apposition. The role of MAMs is critical for intracellular Ca2+ dynamics as they provide hubs for direct Ca2+ exchange between the organelles. A recent experimental study reported correlation between obesity and MAM formation in mouse liver cells, and obesity-related cellular changes that are closely associated with the regulation of Ca2+ dynamics. We constructed a mathematical model to study the effects of MAM Ca2+ dynamics on global Ca2+ activities. Through a series of model simulations, we investigated cellular mechanisms underlying the altered Ca2+ dynamics in the cells under obesity. We found that the formation of MAMs is negatively correlated with the amplitude of cytosolic Ca2+ activities, but positively correlated with that of mitochondrial Ca2+ dynamics and the overall frequency of Ca2+ oscillations. We predict that, as the dosage of stimulus gradually increases, liver cells from obese mice will reach the state of saturated cytosolic Ca2+ concentration at a lower stimulus concentration, compared to cells from healthy mice.Author summaryIt is well known that intracellular Ca2+ oscillations carry encoded signals in their amplitude and frequency to regulate various cellular processes, and accumulating evidence supports the importance of the interplay between the ER and mitochondria in cellular Ca2+ homeostasis. Miscommunications between the organelles may be involved in the development of metabolic diseases. Based on a recent experimental study that spotlighted a correlation between obesity and physical interactions of the ER and mitochondria in mouse hepatic cells, we constructed a mathematical model as a probing tool that can be used to computationally investigate the effects of the cellular changes linked with obesity on global cellular Ca2+ dynamics. Our model successfully reproduced the experimental study that observed a positive correlation between the ER-mitochondrial junctions and the magnitude of mitochondrial Ca2+ responses. We postulate that hepatic cells from lean animals exhibit Ca2+ oscillations that are more robust under higher concentrations of stimulus, compared to cells from obese animals.
Exploring retention factors and job security of nurses in Gauteng public hospitals in South Africa
Authors: Dhanpat Nelesh , Manakana Tlou , Mbacaza Jessica , Mokone Dineo , Mtongana Busisiwe 
Published: November 2018

PurposeThe purpose of this paper is to investigate the relationship between employee retention and job security and the impact of retention factors on the job security of nurses in public hospitals in South Africa. The retention of nurses is essential in public hospitals in South Africa. It is therefore critical that retention strategies are primed to ensure the job security of nurses.Design/methodology/approachThe study is quantitative in nature, adopts a cross-sectional approach and is set within a positivist research paradigm. Pre-established questionnaires were used to collect data. Non-probability sampling was used to select a convenience sample. Questionnaires were distributed to three public hospitals in Johannesburg and 202 responses were received. The psychometric properties of the questionnaire were established through validity and reliability. Inferential and descriptive statistics were deployed to analyse data.FindingsThe study established that there is a relationship between retention factors and job security. The study further identified retention factors as predictors of job security and noted that training and development was the strongest predictor of job security amongst nurses. In addition, the study contributes towards research on retention practices of nurses from a South African perspective.Practical implicationsThe study recommendations are diagrammatically represented. If implemented by human resource practitioners and nursing management, they are likely to enhance job security.Originality/valueThe study provides insights on the retention of nursing professionals in public hospitals in Gauteng and identifies retention factors which contribute most towards job security.
Protecting my baby: a qualitative study of the health promoting practices of pregnant Burmese migrant women living in Thailand
Authors: Phanwichatkul Titaree , Burns Elaine , Liamputtong Pranee , Schmied Virginia 
Published: November 2018

PurposeThe purpose of this paper is to describe Burmese migrant women’s perceptions of health and well-being during pregnancy, their health promoting practices and their experiences with the Thai antenatal services.Design/methodology/approachThe study used an ethnographic design. Observations were conducted in two antenatal clinics in southern Thailand. Ten Burmese migrant women and three Burmese interpreters participated in interviews. Data were analysed using thematic analysis.FindingsThe Burmese women wanted to take care of themselves and their baby to the best of their ability. This included following traditional practices and attending the antenatal clinic if able. Negotiating the demands of earning an income, and protecting their unborn baby, sometimes led to unhealthy practices such as consuming energy drinks and herbal tonics to improve performance. Accessing antenatal care was a positive health seeking behaviour noted in this community, however, it was not available to all.Research limitations/implicationsThis is a small ethnographic study conducted in one Province in Thailand and all Burmese participants were legal migrants. Further research is required to understand the needs of pregnant women not able to access maternity services because of their status as an illegal migrant.Practical implicationsCommunity-based health promotion initiatives need to focus on the nutrition of pregnant women who are migrants living in southern Thailand. New models of care may increase migrant women’s use of antenatal services.Originality/valueMost studies of the health of migrant women are conducted in high-income countries. This study demonstrates the difficulties experienced by women migrating from a low to middle-income country.
Unethical sales behavior neutralization: the impact of salesperson role variables and moderating effects of role relationship orientation
Authors: Munoz Laura , Mallin Michael 
Published: November 2018

Purpose
The purpose of this paper is to explore the relationship between salesperson role perceptions and use of neutralization techniques, given the relationship orientation of the salesperson. Direct relationships between salesperson role conflict, role ambiguity, role task self-efficacy and a salesperson’s propensity to use neutralizations to attribute their unethical selling behavior are tested. The moderating effects of role-relationship orientation on the aforementioned relationships are also explored

Design/methodology/approach
Survey data were collected from 163 (cross-industry, B2B/B2C non-retail) salespeople. Results were analyzed and seven hypotheses were tested using SmartPLS to estimate and evaluate a (partial least squares) structural model.

Findings
The study findings conclude that role ambiguity, role task self-efficacy and role relationship orientation directly impact a salesperson’s tendency to use neutralization techniques to justify unethical sales behavior. Role relationship orientation serves to moderate the relationship between role conflict and neutralization use.

Research limitations/implications
This research integrates attribution and role theories to isolate the conditions where salespeople are prone to use neutralization techniques to justify their unethical behavior. Salesperson role relationship orientation is explored to understand the moderating effects on the salesperson role–neutralization relationships.

Practical implications
Sales managers are provided guidance (e.g. training and coaching) to help salespeople navigate feelings of negative role perceptions (role conflict, role ambiguity, role self-efficacy) to minimize the impact on justification of unethical sales behaviors.

Originality/value
This research builds on the sales and ethics literatures by incorporating role and attribution theory to better understand how salespeople approach dealing with their own unethical behavior and the implications on maintaining relationships with their customers.
Strategic plurality in intergenerational hand-over
Authors: Osnes Gry , Hök Liv , Yanli Hou Olive , Haug Mona , Grady Victoria , Grady James D. 
Published: November 2018

Purpose
With strategy-as-practice theory the authors explore successful business-owning families hand-over of roles to the next generation. The authors argue for the usefulness of strategy-as-practice theory in exploring the complexity and plurality of best practices in intergenerational hand-over. The paper aims to discuss these issues.

Design/methodology/approach
A cross-cultural in-depth case study with best practice cases from China, Germany, Sweden, England, Tanzania, Israel and the USA, based on in-depth interviews of family members and non-family employees.

Findings
The authors identified three different succession patterns: a “monolithic practice,” a distributed leadership hand-over, and active ownership with a non-family managing director/CEO. Two other types of hand-over practices were categorized as incubator patterns that formed a part of, or replaced, what we traditionally see as a hand-over of roles. Families would switch between these practices.

Research limitations/implications
Surprisingly, a monolithic succession practice (a one-company-one-leadership role) was rarely used. Quantitative and qualitative research should consider, as should advisors to family owners and family businesses, the plurality of succession practices. Education should explore a variation of succession and how the dynamic of gender influences the process.

Practical implications
Giving practitioners, such as research and practitioner, an overview of strategic options so as to explore these in a client or research case.

Social implications
Adding the notions that the family is an incubator for new entrepreneurship makes it possible to show how not only sector or public policy generate new ventures. That family as source of entrepreneurship has been well established in the field but it mainstream policy thinking the family is not seen as such a source.

Originality/value
The paper offers an integrative model of the complexity of hand-over practices of ownership and leadership roles. It shows how these practices are fundamental for understanding how a family’s ownership and their leadership of businesses and new entrepreneurship develops.