bluuebunny/crossref_metadata_2025 huggingface dataset:
The Experience of Prisoners’ Parents: A Meta‐Synthesis of Qualitative Studies
Authors: Gueta Keren
Published: August 2017

The parents of prisoners have long drawn the attention of researchers, due to their role in the etiology of criminality as well as the importance of their support of their offspring during and after incarceration. However, although studies have shown that the parents of prisoners experience high levels of distress, burden, and social stigma, research into their experience is only now beginning to emerge. This metasynthesis examined the limited body of qualitative research on the experience of prisoners’ parents, as an exploratory step toward advancing the understanding of their experience. Relevant terms were used to systematically search key databases. Ten small‐scale studies, which varied in focus, location, and disciplinary orientation, met the inclusion criteria. The synthesis produced four core themes, reflecting findings regarding parents’ (primarily mothers’) experience of their offspring's incarceration: parenting from a distance; the burden of care; troubled parental identity; and social reaction. Furthermore, the findings suggested a number of possible mediating factors of this experience, such as parents’ social capital and their cognitive appraisal of their offspring's criminality. These themes imply a possible experience of “imprisonment by association” among the parents of inmates and illuminate features that may be unique to them. Given the inherent limitations regarding generalizability of a metasynthesis and the heterogeneity of the experiences of the parents represented by the articles reviewed, the findings call for future large‐scale quantitative studies to explore the challenges and therapeutic needs of parents of prisoners regarding the themes identified.
Risk of malignancies in autoimmune hepatitis type 1 patients with a long‐term follow‐up in Japan
Authors: Arinaga‐Hino Teruko , Ide Tatsuya , Miyajima Ichiro , Ogata Kei , Kuwahara Reiichiro , Amano Keisuke , Kawaguchi Toshihiro , Nakamura Toru , Kawaguchi Takumi , Koga Hironori , Yonemoto Koji , Torimura Takuji ,   the Kurume Autoimmune Hepatitis Study Group
Published: August 2017

Aim

The risk of malignancies in autoimmune diseases is high and is regarded to be due to immunological abnormalities, the use of immunosuppressive agents, and/or chronic inflammation. The aim of this study was to investigate the incidence and risk of malignancies in patients with autoimmune hepatitis (AIH) type 1 in Japan.

Methods

Two hundred and fifty‐six patients diagnosed with AIH were enrolled. A person‐year calculation was carried out for AIH patients, and the numbers of expected events were clarified using data from “The Monitoring of Cancer Incidence in Japan Project” in order to examine the standard incident rate (SIR) of each type of malignancy. Biochemical data regarding carcinogenesis and its background factors were also examined.

Results

Twenty‐seven patients (10.5%) developed malignancies; 11 (4.3%) with hepatobiliary cancer and 16 (6.3%) with extrahepatic malignancies. The overall SIR for malignancies in AIH was significantly high at 2.04 (95% confidence interval [CI], 1.34–2.96), and was high among female patients at 2.49 (95% CI, 1.60–3.71). The SIR for hepatobiliary cancer was 14.14 (95% CI, 7.05–25.30), and was markedly high for female patients at 21.83 (95% CI, 10.45–40.16). The SIR for oral/pharyngeal cancer was significantly high for female patients at 14.61 (95% CI, 1.64–52.77). The risk factors for hepatobiliary cancer at the diagnosis of AIH were low levels of alanine aminotransferase (P = 0.0226), low platelet counts (P < 0.0001), and cirrhosis (P = 0.0004). The risk factor for extrahepatic malignancy was relapse of AIH (P = 0.0485).

Conclusion

The risk of malignancies was generally high among AIH patients. Those with the risk factors of malignancies should be carefully followed up.
Prioritizing novel and existing ambulance performance measures through expert and lay consensus: A three‐stage multimethod consensus study
Authors: Coster Joanne E. , Irving Andy D. , Turner Janette K. , Phung Viet‐Hai , Siriwardena Aloysius N.
Published: August 2017

Background

Current ambulance quality and performance measures, such as response times, do not reflect the wider scope of care that services now provide. Using a three‐stage consensus process, we aimed to identify new ways of measuring ambulance service quality and performance that represent service provider and public perspectives.

Design

A multistakeholder consensus event, modified Delphi study, and patient and public consensus workshop.

Setting and participants

Representatives from ambulance services, patient and public involvement (PPI) groups, emergency care clinical academics, commissioners and policymakers.

Results

Nine measures/principles were highly prioritized by >75% of consensus event participants, including measures relating to pain, patient experience, accuracy of dispatch decisions and patient safety. Twenty experts participated in two Delphi rounds to further refine and prioritize measures; 20 measures in three domains scored ≥8/9, indicating good consensus, including proportion of calls correctly prioritized, time to definitive care and measures related to pain. Eighteen patient/public representatives attended a consensus workshop, and six measures were identified as important. These include time to definitive care, response time, reduction in pain scores, calls correctly prioritized to appropriate levels of response and survival to hospital discharge for treatable emergency conditions.

Conclusions

Using consensus methods, we identified a shortlist of ambulance outcome and performance measures that are important to ambulance clinicians and service providers, service users, commissioners, and clinical academics, reflecting current pre‐hospital ambulance care and services. The measures can potentially be used to assess pre‐hospital quality or performance over time, with most calculated using routinely available data.
Patient‐centred care is a way of doing things: How healthcare employees conceptualize patient‐centred care
Authors: Fix Gemmae M. , VanDeusen Lukas Carol , Bolton Rendelle E. , Hill Jennifer N. , Mueller Nora , LaVela Sherri L. , Bokhour Barbara G.
Published: August 2017

Background

Patient‐centred care is now ubiquitous in health services research, and healthcare systems are moving ahead with patient‐centred care implementation. Yet, little is known about how healthcare employees, charged with implementing patient‐centred care, conceptualize what they are implementing.

Objective

To examine how hospital employees conceptualize patient‐centred care.

Research Design

We conducted qualitative interviews about patient‐centred care during site four visits, from January to April 2013.

Subjects

We interviewed 107 employees, including leadership, middle managers, front line providers and staff at four US Veteran Health Administration (VHA) medical centres leading VHA's patient‐centred care transformation.

Measures

Data were analysed using grounded thematic analysis. Findings were then mapped to established patient‐centred care constructs identified in the literature: taking a biopsychosocial perspective; viewing the patient‐as‐person; sharing power and responsibility; establishing a therapeutic alliance; and viewing the doctor‐as‐person.

Results

We identified three distinct conceptualizations: (i) those that were well aligned with established patient‐centred care constructs surrounding the clinical encounter; (ii) others that extended conceptualizations of patient‐centred care into the organizational culture, encompassing the entire patient‐experience; and (iii) still others that were poorly aligned with patient‐centred care constructs, reflecting more traditional patient care practices.

Conclusions

Patient‐centred care ideals have permeated into healthcare systems. Additionally, patient‐centred care has been expanded to encompass a cultural shift in care delivery, beginning with patients' experiences entering a facility. However, some healthcare employees, namely leadership, see patient‐centred care so broadly, it encompasses on‐going hospital initiatives, while others consider patient‐centred care as inherent to specific positions. These latter conceptualizations risk undermining patient‐centred care implementation by limiting transformational initiatives to specific providers or simply repackaging existing programmes.
Carers' involvement in decision making about antipsychotic medication: A qualitative study
Authors: Stomski Norman J. , Morrison Paul
Published: August 2017

Background

Current Australian mental health policy recommends that carers should be involved in the provision of mental health services. Carers often provide intensive support to mental health consumers and gain detailed insight into their lives. As such, carers could make valuable contributions to well‐informed decisions about mental health consumers' use of antipsychotic medication.

Objectives

The aim of this study was to explore carers' participation in antipsychotic medication decision making.

Methods

Snowball sampling was used to enrol 29 carers in this study. Of these carers, 19 participated in semi‐structured interviews, and ten participated in a focus group. Data were analysed thematically.

Results

Four main themes emerged from the analysis. The findings highlighted that carers typically received little or no information about antipsychotic medication. Carers commonly addressed the shortfall in information by obtaining additional information through online sources or distributing among carer networks material that they had developed themselves. Almost all carers emphasized that they should be involved in decisions about antipsychotic medication, but noted that they were typically excluded. The lack of involvement in medication decisions was a source of frustration, as carers could contribute saliently through sharing detailed knowledge about mental health consumers' lives, address communication gaps that resulted from disjointed care and improve communication between health professionals and mental health consumers.

Conclusion

Health professionals could consider improving the extent to which they collaborate with carers in medication decisions.
Transcriptional repressor Blimp1 regulates follicular regulatory T‐cell homeostasis and function
Authors: Yang Guang , Yang Xiaosu , Zhang Junmei , Li Guancheng , Zheng Dandan , Peng Anjiao , Hu Jue , Xu Liqun , Yang Baifeng , Yang Huan , Zhou Wenbin , Tuzun Erdem , Li Jing
Published: August 2017

The B‐lymphocyte‐induced maturation protein 1 (Blimp1) regulates T‐cell homeostasis and function. Loss of Blimp1 could double the proportion of follicular regulatory T (Tfr) cells. However, the effects that Blimp1 may have on the function of Tfr cells remain unknown. Here we document the function for Blimp1 in Tfr cells in vitro and in vivo. Data presented in this study demonstrate that Tfr cells indirectly inhibit the activation and differentiation of B cells by negatively regulating follicular helper T cells, so lowering the secretion of antibody. Lack of Blimp1 makes the immune suppression function of Tfr cells impaired in vitro. In the in vivo study, adoptive transfer of Tfr cells could reduce immune responses in germinal centres and relieve the muscle weakness symptoms of mice with experimental autoimmune myasthenia gravis. Blimp1 deficiency resulted in reduced suppressive ability of Tfr cells. This study identifies that Tfr cells are potent suppressors of immunity and are controlled by Blimp1.
The conceptualization of childhood in North American pediatric dentistry texts: a discursive case study analysis
Authors: Makansi Nora , Carnevale Franco A. , Macdonald Mary Ellen
Published: August 2017

Background

In recent years, conceptions of childhood have been evolving towards an increased recognition of children as active agents, capable of participating in the determination of their wellbeing. In pediatric dentistry, the extent to which these conceptions are being discursively endorsed is not well known.

Aim

The aim of this investigation was to examine the discursive construction of childhood in seminal North American pedagogical dentistry materials.

Design

We conducted a qualitative discourse analysis of a sample of prominent texts using a sociological discourse analysis approach.

Results

We analyzed the latest edition of Macdonald and Avery's textbook (Chapter: Non pharmacologic management of children's behaviors) and the clinical practice guidelines published by the American Academy of Pediatric Dentistry, AAPD (Behavior guidance for the pediatric dental patient). The analysis produced five salient discursive categories: socialization through behavior modification; development and behavior; paternalism; the utility of child‐centered communication; and consequentialism. While there were instances of a child‐centered focus in the texts, the main discourses were rooted in developmentalism and behaviorism. There was scant acknowledgment of the importance of children's agency or voice, which runs contrary to child‐centered discourses and practices in related disciplines (e.g., pediatric medicine, nursing).

Conclusion

Predominant discourses in pediatric dentistry suggest a paternalistic, behaviorist approach to the ‘management’ of children in the dental office, focused primarily on completing interventions. Priorities for the future development of pediatric dentistry are discussed, integrating more child‐centered approaches.
Public sector restructuring and the re‐regulation of industrial relations: the three‐decade project of privatisation, liberalisation and marketisation in Royal Mail
Authors: Mustchin Stephen
Published: August 2017

The British postal service, Royal Mail, was privatised in 2013, following failed attempts at divestiture in 1994 and 2009. This article analyses processes of marketisation, liberalisation and privatisation, highlighting how strong workplace‐centred union presence allowed for considerable influence and bargaining gains within such highly sensitive political projects of restructuring.
Neural androgen receptor overexpression affects cell number in the spinal nucleus of the bulbocavernosus
Authors: Coome L. A. , Swift‐Gallant A. , Ramzan F. , Melhuish Beaupre L. , Brkic T. , Monks D. A.
Published: August 2017

The spinal nucleus of the bulbocavernosus (SNB) is a sexually dimorphic neuromuscular system in which the masculinisation of cell number is assumed to depend on the action of perinatal androgen in non‐neural targets, whereas the masculinisation of cell size is assumed to depend primarily on the action of adult androgen on SNB cells themselves. To test these hypotheses, we characterised the SNB of Cre/loxP transgenic mice that overexpress androgen receptor (AR) throughout the body (CMV‐AR) or in neural tissue only (Nestin‐AR). Additionally, we examined the effects of androgen manipulation in male mutants and wild‐type (WT) controls. We reproduced the expected sex differences in both motoneurone number and size, as well as the expected adult androgen dependence of SNB size. We found effects of genotype such that both Nestin‐AR and CMV‐AR have more SNB motoneurones than WT littermates and also that CMV‐AR females have larger SNB motoneurones than Nes‐AR or WT females. These results raise the possibility that AR can act in neurones and/or glia to rescue SNB motoneurones, as well as on non‐neural AR to increase SNB cell size.
Enabling a Disaster‐Resilient Workforce: Attending to Individual Stress and Collective Trauma
Authors: Raveis Victoria H. , VanDevanter Nancy , Kovner Christine T. , Gershon Robyn
Published: August 2017

Purpose

Superstorm Sandy forced the evacuation and extended shutdown of New York University Langone Medical Center. This investigation explored how nurses were impacted by the disasters and how they can best be supported in their nursing responsibilities.

Design

Sequential mixed methods were used to explore the psychosocial issues nurses experienced throughout the course of this natural disaster and its lingering aftermath.

Methods

In‐depth interviews were conducted from April to June 2013 with a subsample of nurses who participated in the evacuation deployment (n = 16). An anonymous, Internet‐based cross‐sectional survey sent to all registered nurses employed at the hospital at the time of the storm explored storm impact and recovery. Between July and September 2013, 528 surveys were completed.

Findings

The qualitative data revealed challenges in balancing professional obligations and personal concerns. Accounts described dealing in the immediate recovery period with unexpected job changes and resultant work uncertainty. The storm's lingering aftermath did not signify restoration of their predisaster lifestyle for some, but necessitated coping with this massive storm's long‐lasting impact on their personal lives and communal loss.

Conclusions

Nurses working under the rapidly changing, uncontrolled, and potentially dangerous circumstances of a weather‐related disaster are also experiencing concerns about their families’ welfare and worries about personal loss. These multiple issues increase the psychosocial toll on nurses during a disaster response and impending recovery.

Clinical Relevance

Awareness of concerns and competing demands nurses experience in a disaster and aftermath can inform education and services to enable nurses to perform their critical functions while minimizing risk to patients and themselves.
Artepillin C as a targeting survivin molecule in oral squamous cell carcinoma cells in vitro: A preliminary study
Authors: Pang Seokjoon , Yee Michael , Saba Yasmin , Chino Takahiro
Published: August 2017

Background

Survivin, a member of the inhibitor of apoptosis family, is overexpressed in most human tumors, but undetectable in normal adult tissues. It is a promising target molecule in cancer treatment, as interference in its function promotes apoptosis. Artepillin C, a major, biologically active ingredient of Brazilian propolis, possesses anticancer activity against several cancer cells with different tissue origins. However, little is known about its bioactivity on oral squamous cell carcinoma cells or its effect on survivin expression. The aim of this study was to investigate the cytotoxic and antisurvivin activities of artepillin C in oral squamous cell carcinoma cells.

Methods

HSC‐3 human oral squamous cell carcinoma cells were treated with varying doses of artepillin C for up to 72 hours. Cell viability was measured by WST‐1, and the cytotoxic effects of artepillin C on HSC‐3 cells were quantified with flow cytometry. The survivin levels were determined by ELISA.

Results

Artepillin C exhibited dose‐ and time‐dependent cytotoxic effects on HSC‐3 cells. Flow cytometric analysis showed that 22% of untreated HSC‐3 cells underwent spontaneous cell death, whereas 77.32% of the cells were killed in response to the highest dose of artepillin C at 72 hours. Survivin expression was reduced in treated cells.

Conclusions

HSC‐3 cells are vulnerable to artepillin C in a dose‐ and time‐dependent manner. HSC‐3 cell death induced by artepillin C, at least in part, was a result of a decrease in survivin levels.
Nonstructural protein 5A resistance profile in patients with chronic hepatitis C treated with ledipasvir‐containing regimens without sofosbuvir
Authors: Kitrinos K. M. , Corsa A. C. , Worth A. , Hedskog C. , Brainard D. M. , Miller M. D. , Mo H.
Published: August 2017

The study aimed to evaluate the effects of baseline hepatitis C virus (HCV) nonstructural protein 5A (NS5A) resistance‐associated substitutions (RASs) on sustained virologic response to ledipasvir (LDV)‐containing regimens in the absence of sofosbuvir (SOF) in patients with HCV genotype (GT) 1 infection across 6 phase 2 clinical studies. We analysed data from 1103 patients who received either LDV + vedroprevir (NS3 protease inhibitor) + tegobuvir (NS5B inhibitor) ± ribavirin or LDV + ribavirin + pegylated interferon. Population sequencing of HCV NS5A was performed at baseline and at virologic failure from patient plasma samples. Of 1045 patients with available baseline sequences, 747 (67.7%) had GT1a, and 298 (26.9%) had GT1b infection. The overall prevalence of NS5A RASs at baseline was 9.4%; 7.6% (57/747) and 13.8% (41/298) of patients with GT1a and GT1b infection, respectively. The majority of GT1a‐infected patients with NS5A RASs at baseline had a single NS5A RAS (78.9%) at NS5A positions K24R, M28T, Q30H/L, L31M and Y93H/N/C/S. The spectrum of NS5A RASs detected in GT1b patients was much less diverse compared to GT1a patients, with all patients harbouring a single NS5A RAS either L31M or Y93H/C. For patients treated with LDV‐containing regimens in the absence of SOF, the presence of baseline NS5A RASs was associated with low SVR rates. In patients with virologic failure, nearly all had either pre‐existing and/or emergent NS5A RASs: 287/287 (100%) and 40/42 (95.2%) patients with GT1a and GT1b infection, respectively. Three novel NS5A substitutions were identified as emergent NS5A RASs: K26E and S38F in GT1a; and L31I in GT1b. In conclusion, the presence of NS5A RASs at baseline reduced the SVR rate in patients treated with LDV in combination vedroprevir + tegobuvir ± ribavirin or ribavirin + pegylated interferon. Virologic failure was associated with the detection of NS5A RASs in nearly all patients. These results suggest that the resistance barrier may differ depending on HCV drug combination and may be more important than that of the individual DAAs.
Poor adherence to hepatocellular carcinoma surveillance: A systematic review and meta‐analysis of a complex issue
Authors: Zhao Changqing , Jin Mingjuan , Le Richard Hieu , Le Michael Huan , Chen Vincent Lingzhi , Jin Michelle , Wong Grace Lai‐Hung , Wong Vincent Wai‐Sun , Lim Young‐Suk , Chuang Wan‐Long , Yu Ming‐Lung , Nguyen Mindie H.
Published: August 2017

Background & Aims

Hepatocellular carcinoma (HCC) surveillance is associated with improved outcomes and long‐term survival. Our goal is to evaluate adherence rates to HCC surveillance.

Methods

We performed a systematic search of the PubMed and Scopus databases and abstract search of relevant studies from recent major liver meetings. All searches and data extraction were performed independently by two authors. Analysis was via random‐effects models and multivariate meta‐regression.

Results

A total of 22 studies (n = 19 511) met inclusion criteria (original non‐interventional studies with defined cirrhosis or chronic hepatitis B or chronic hepatitis C with advanced fibrosis populations, and surveillance tests and intervals). Overall adherence rate was 52% (95% CI 38%‐66%). Adherence was significantly higher in cirrhotic patients compared to chronic hepatitis B and other high‐risk patients, in European compared to North American studies, in less than 12‐month compared to yearly surveillance intervals, and in prospective compared to retrospective studies (71%, 95% CI 64%‐78% vs 39%, 95% CI 26%‐51%, P < .001). The between‐study heterogeneity of all above analyses was significant (P < .001). Only the study design (retrospective vs prospective cohort) had statistical significance in a multivariate meta‐regression model (P < .05) and could account for some of the differences above.

Conclusions

Overall adherence rate to HCC surveillance was suboptimal at 52% with no significant differences by liver disease aetiology or study location in multivariate meta‐regression analysis. Further research and educational efforts are needed to improve the current rate of HCC surveillance.
Error analysis of finite difference and Markov chain approximations for option pricing
Authors: Li Lingfei , Zhang Gongqiu
Published: August 2017

Mijatović and Pistorius proposed an efficient Markov chain approximation method for pricing European and barrier options in general one‐dimensional Markovian models. However, sharp convergence rates of this method for realistic financial payoffs, which are nonsmooth, are rarely available. In this paper, we solve this problem for general one‐dimensional diffusion models, which play a fundamental role in financial applications. For such models, the Markov chain approximation method is equivalent to the method of lines using the central difference. Our analysis is based on the spectral representation of the exact solution and the approximate solution. By establishing the convergence rate for the eigenvalues and the eigenfunctions, we obtain sharp convergence rates for the transition density and the price of options with nonsmooth payoffs. In particular, we show that for call‐/put‐type payoffs, convergence is second order, while for digital‐type payoffs, convergence is generally only first order. Furthermore, we provide theoretical justification for two well‐known smoothing techniques that can restore second‐order convergence for digital‐type payoffs and explain oscillations observed in the convergence for options with nonsmooth payoffs. As an extension, we also establish sharp convergence rates for European options for a rich class of Markovian jump models constructed from diffusions via subordination. The theoretical estimates are confirmed using numerical examples.
Acute fall and long‐term rise in oxygen saturation in response to meditation
Authors: Bernardi Nicolò F. , Bordino Marco , Bianchi Lucio , Bernardi Luciano
Published: August 2017

The effects of meditation on arterial and tissue oxygenation are unknown and difficult to assess because respiration is often altered, directly or indirectly, during meditation practice. Thus, changes in respiration may affect cardiovascular responses independently from meditation. In this study, we aim to isolate the specific effect of meditation on arterial and tissue oxygenation and other cardiorespiratory indexes while systematically controlling for the role of respiration. Furthermore, we aim to clarify to what extent prior expertise in meditation practice is needed to observe reliable changes. Eighty participants, half with and half without prior meditation experience, were tested while pacing breathing at predetermined rates, in the presence or absence of mantra meditation instructions, and in a body scan meditation that did not involve controlled breathing. Continuous recordings were acquired for arterial and brain oxygenation, respiratory excursion, electrocardiogram, skin vasomotion, and blood pressure. In both groups, meditation acutely decreased arterial and cerebral oxygen saturation, reduced chemoreflex sensitivity, and prolonged the RR interval, independently of respiration. Conversely, slow breathing improved heart rate variability, independently of concurrent meditation. In addition to the immediate effects of meditation, the individuals with long‐term practice of meditation had overall higher arterial and cerebral oxygen saturation, overall lower blood pressure, and slower baseline respiration. Meditation acutely lowers arterial and tissue oxygenation. A repeated exposure to this condition may lead to long‐term adaptation and, through increased ventilatory efficiency and improved gas exchanges, to an increase in baseline oxygenation. Meditation induces favorable changes in cardiovascular and respiratory end points of clinical interest.
Of oysters, witches, birds, and anchors: Conceptions of space and travel in Pierre de Lancre
Authors: Maus de Rolley Thibaut
Published: August 2017

In 1609, the Bordeaux judge Pierre de Lancre led a brutal witch‐hunt in the Pays de Labourd, a territory in the southwestern tip of France. In his Tableau de l'inconstance des mauvais anges et demons (1612), Lancre described this fragment of the French Basque country as a New World of sorts inhabited by barely civilized people, and an inverted image of his own land: a prosperous and peaceful estate in Sainte‐Croix‐des‐Monts, in the wine‐making region of Bordeaux. The Pays de Labourd was a place of frenzy and mobility, which made it the devil's natural abode, and horrified Lancre, whose very name – a combination of the stone (pierre) and the anchor (ancre) – designated him as an incarnation of constancy and stability. This article explores the conceptions of space and travel at work in Lancre's writings, and examines the personal, literary and cultural roots of his demonization of movement. Replacing the 1612 Tableau within the wider context of Lancre's other works, it argues that Lancre's view of the Pays de Labourd and his discourse on witchcraft was shaped to a great extent by a neo‐Stoic condemnation of travel and mobility.
The Roles of Job and Worker Restructuring in Aggregate Wage Growth Dynamics1
Authors: Kauhanen Antti , Maliranta Mika
Published: August 2017

We propose an approach for measuring and analyzing the dynamics of the standard aggregate wage growth of macro statistics with micro data. Our method decomposes the aggregate wage growth into the wage growth of job stayers and into various terms related to job and worker restructuring. This method produces explicit expressions with clear interpretations for the various restructuring components. Using comprehensive longitudinal employer–employee data, we study how job and worker restructuring influence the aggregate wage growth and its cyclicality. The results highlight the importance of drawing a sharp distinction between job and worker restructuring in the analysis of aggregate wage growth dynamics.
Mechanical properties of rock specimens containing pre‐existing flaws with 3D printed materials
Authors: Tian Wei , Han NV
Published: August 2017

Three‐dimensional printing (3DP) technology has undergone a rapid development in the last few years and become a useful tool in many research fields. This study applied 3DP technology to prepare solid specimens simulating rock‐type materials combined with computed tomography scanning and 3D image processing. 3DP specimens with pre‐existing flaws in different inclination angles were fabricated and then conducted a series of mechanical experiments to study the influence of number and inclination angle of pre‐existing flaw on strength and failure patterns under uniaxial compression. The experimental results indicated that 3DP specimens had similar mechanical properties with rock‐type materials. The 3DP specimens with 2 pre‐existing flaws had lower compressive strength with an average of 4.26 MPa, whereas compressive strength of specimens with one flaw was no less than 5.08 MPa. Different inclination angles led to various failure patterns and compressive strengths, which took on a V‐shaped curve with the increase of inclination angles. This study demonstrated that 3DP technology provided a new perspective for conducting laboratory experimental research of rock mechanics.
Preanalytic processing of rat plasma influences thrombin generation and fibrinolysis assays
Authors: Brooks Marjory B. , Stablein Alyssa P. , Johnson Lynn , Schultze Albert Eric
Published: August 2017

Background

Thrombin generation assays (TGA) have potential applications as measures of hemostatic balance in animal models. However, variations in plasma processing greatly influence human TGA, and may also impact on the translational value of TGA in animal studies.

Objectives

The purpose of the study was to compare the performance characteristics of Sprague–Dawley rat plasma prepared by single vs double centrifugation protocols in TGA and fibrinolysis assays.

Methods

Platelet‐poor plasma (PPP) from adult rats (n = 20 males; 20 females) was prepared by centrifugation at 1200g × 12 min, or 2 sequential centrifugations of 2500g × 15 min. Plasma aliquots were assayed fresh and after freeze–thaw in a commercial fluorogenic TGA (Technothrombin TGA, Technoclone) using 2 different trigger reagents containing approximately 7 pM human tissue factor. In addition to TGA variables (lag time, peak thrombin, endogenous thrombin potential), we compared clotting time test and fibrinogen concentration, residual platelet and platelet‐derived microparticle (PMP) counts measured by flow cytometry, and variables of fibrin clot formation and lysis measured in turbidimetric assays.

Results

Single‐centrifugation PPP demonstrated significantly greater thrombin‐generating potential regardless of trigger reagent, yielded higher residual platelet and procoagulant PMP counts, and more stable fibrin clot profiles. The influence of a freeze–thaw cycle on TGA varied depending on trigger reagent, and male sex was associated with an overall “procoagulant” phenotype.

Conclusions

Preanalytic processing and sex have significant effects on many functional measures of hemostasis in rats. A standardized double centrifugation protocol to prepare PPP is recommended for future studies.
Fecal shedding of Campylobacter jejuni and Campylobacter coli among feral pigs in Texas
Authors: Cummings K. J. , Rodriguez‐Rivera L. D. , McNeely I. , Suchodolski J. S. , Mesenbrink B. T. , Leland B. R. , Bodenchuk M. J.
Published: August 2017

The population and range of feral pigs in the United States are rapidly expanding, yet key knowledge gaps exist regarding their role in the ecology and transmission of foodborne pathogens. Our objectives were to estimate the prevalence of Campylobacter jejuni and Campylobacter coli shedding among feral pigs throughout Texas and to identify risk factors for positive status. Faecal samples were collected from feral pigs in Texas from February 2014 through May 2015, and target organisms were detected using PCR assays. The prevalence of C. jejuni shedding was 1.6% (6/370), and the prevalence of C. coli shedding was 3.5% (13/370). C. coli shedding was significantly more common (p = .008) among female pigs than among male pigs. Feral pigs may represent a source of human campylobacteriosis.
Incoherent Waves in Fluid-Saturated Sintered Granular Systems: Scattering Phenomena
Authors: Güven Ibrahim , Luding Stefan , Steeb Holger
Published: August 2017

The incoherent transport of ultrasound waves in water-saturated sintered glass bead packings is experimentally investigated. The spectral energy density of scattered high-frequency waves is explained by a diffusion wave equation. Immersion broadband transducers with central frequencies of 1 MHz are positioned at a distance of 73 mm to the porous sample. The diffusion coefficient and quality factor are predicted from a diffusion approximation of the time-dependent intensity curve to the ensemble-averaged measurement data. From the diffusion coefficient, we deduce a mean-free path for scattering events at l*=0.87±0.03 mm close to the range of particle diameters of the samples (1.0<dp<1.2 mm). Results are in good agreement with observations from Jia (2004, “Codalike Multiple Scattering of Elastic Waves in Dense Granular Media,” Phys. Rev. Lett., 93(15), p. 154303) observed for nonsintered and consolidated bead packings (0.6<dp<0.8 mm). The low-quality factor Q=190±10 indicates a high amount of intrinsic damping of the scattered waves although water was used as saturating and coupling fluid.
Detailed Examination of a Modified Two-Stage Micro Gas Turbine Combustor
Authors: Schwärzle Andreas , Monz Thomas O. , Huber Andreas , Aigner Manfred
Published: August 2017

Jet-stabilized combustion is a promising technology for fuel flexible, reliable, highly efficient combustion systems. The aim of this work is a reduction of NOx emissions of a previously published two-stage micro gas turbine (MGT) combustor (Zanger et al., 2015, “Experimental Investigation of the Combustion Characteristics of a Double-Staged FLOX-Based Combustor on an Atmospheric and a Micro Gas Turbine Test Rig,” ASME Paper No. GT2015-42313 and Schwärzle et al., 2016, “Detailed Examination of Two-Stage Micro Gas Turbine Combustor,” ASME Paper No. GT2016-57730), where the pilot stage (PS) of the combustor was identified as the main contributor to NOx emissions. The geometry optimization was carried out regarding the shape of the pilot dome and the interface between PS and main stage (MS) in order to prevent the formation of high-temperature recirculation zones. Both stages have been run separately to allow a detailed understanding of the flame stabilization within the combustor, its range of stable combustion, the interaction between both stages, and the influence of the modified geometry. All experiments were conducted at atmospheric pressure and an air preheat temperature of 650  °C. The flame was analyzed in terms of shape, length, and lift-off height, using OH* chemiluminescence (OH-CL) images. Emission measurements for NOx, CO, and unburned hydrocarbons (UHC) emissions were carried out. At a global air number of λ = 2, a fuel split variation was carried out from 0 (only PS) to 1 (only MS). The modification of the geometry leads to a decrease in NOx and CO emissions throughout the fuel split variation in comparison with the previous design. Regarding CO emissions, the PS operations are beneficial for a fuel split above 0.8. The local maximum in NOx emissions observed for the previous combustor design at a fuel split of 0.78 was not apparent for the modified design. NOx emissions were increasing, when the local air number of the PS was below the global air number. In order to evaluate the influence of the modified design on the flow field and identify the origin of the emission reduction compared to the previous design, unsteady Reynolds-averaged Navier–Stokes simulations were carried out for both geometries at fuel splits of 0.93 and 0.78, respectively, using the DLR (German Aerospace Center) in-house code turbulent heat release extension of the tau code (theta) with the k–ω shear stress transport turbulence model and the DRM22 (Kazakov and Frenklach, 1995, “DRM22,” University of California at Berkeley, Berkeley, CA, accessed Sept. 21, 2017, http://www.me.berkeley.edu/drm/) detailed reaction mechanism. The numerical results showed a strong influence of the recirculation zones on the PS reaction zone.
A Multilayer Taxonomy of Cost Estimation Techniques, Looking at the Whole Product Lifecycle
Authors: Altavilla Stefania , Montagna Francesca , Cantamessa Marco
Published: August 2017

Product cost estimation (PCE) still draws the attention of researchers and practitioners, even though it has been extensively discussed in the literature for more than 20 years. This is due to its central impact on the company's performance. Nowadays, the adoption of cost estimation methods seems to be limited, despite the multitude of examples and applications available. A possible reason is the multitude of approaches and techniques proposed in the literature, which, instead of representing a guide for enabling possible implementations, actually create confusion and ambiguity on their appropriateness for a particular application. Hence, this paper aims to provide a systematic review of the recent literature in the field of PCE, and intensively investigates the aspects that can enable a more conscious decision on the type of technique to be adopted. This results in the identification of five different perspectives, which can be taken simultaneously into account. By combining the different viewpoints, a new multilayer framework is derived, with a specific focus on the whole product life cycle. The proposed framework can be used as a decision-making tool by both researchers and practitioners. In fact, the former group can benefit from the new structure, as a way to identify new areas of possible research opportunities. The latter group is provided an operative guide for the application in industrial contexts.
The Economic Potential and Technical Feasibility of Hybridizing Coal Power Plants With Molten Salt Parabolic Troughs
Authors: Schuknecht Nathan H. , Kulbeik Pamela A. , O’Rourke Deven M.
Published: August 2017

When a coal-fired power plant is considered for closure, arguments are commonly made about the loss of jobs and unrealized investments. Facing this pressure, governments are reluctant to enact enforceable emission standards, and these plants continue to emit pollutants into the atmosphere. As the equipment ages, the plants may retire, but in their lifetime they will cause irreversible environmental damage. This report presents a method to mediate this damage, create jobs, maintain the efficiency of the turbine, and maintain or increase the capacity factor of the plant.

Solar parabolic troughs using molten salt technology are scalable and can meet the steam conditions of a standard Rankine cycle coal-fired power plant. A marriage of these technologies allows the parabolic trough field to be installed without new power generation equipment. The turbine, generator, and transmission equipment are already in place, and when compared to a standalone concentrated solar power (CSP) plant, can be amortized over a greater number of operational hours without the use of very large amounts of thermal storage. That allows for a reduction in capital investment compared to a greenfield CSP plant, and reduces the levelized cost of energy (LCOE) from the solar contribution to well below current US Department of Energy SunShot targets.

Coal-fired plant operators note that they typically cannot operate at partial power output without reducing the efficiency of their turbine accordingly. So, while a photovoltaic hybridization can take advantage of existing transmission infrastructure, it will require that the coal-fired system reduces its output and will consequently reduce the efficiency of the coal cycle. If we have to burn coal, we should do it in the most efficient way possible. Hybridizing with a molten salt parabolic trough installation makes use of the same turbine as the coal-fired system, which maintains the overall efficiency of the turbine at its design point and optimal load. With this model, the coal plant can operate at full power, reduce overall usage of coal while maintaining or even increasing employment opportunities, and reduce CO2 emissions.
Heat Transfer to Vertical Dense Granular Flows at High Operating Temperatures
Authors: Watkins Megan F. , Gould Richard D.
Published: August 2017

Ceramic particles as a heat transfer fluid for concentrated solar power towers offers a variety of advantages over traditional heat transfer fluids. Ceramic particles permit the use of very high operating temperatures, being limited only by the working temperatures of the receiver components, as well as demonstrate the potential to be used for thermal energy storage. A variety of system configurations utilizing ceramic particles are currently being studied, including upward circulating beds of particles, falling particle curtains, and flows of particles over an array of absorber tubes. The present work investigates the use of gravity-driven dense granular flows through cylindrical tubes, which demonstrate solid packing fractions of approximately 60%. Previous work demonstrated encouraging results for the use of dense flows for heat transfer applications and examined the effect of various parameters on the overall heat transfer for low temperatures. The present work examined the heat transfer to dense flows at high operating temperatures more characteristic of concentrated solar power tower applications. For a given flow rate, the heat transfer coefficient was examined as a function of the mean flow temperature by steadily increasing the input heat flux over a series of trials. The heat transfer coefficient increased almost linearly with temperature below approximately 600°C. Above 600°C, the heat transfer coefficient increased at a faster rate, suggesting an increased radiation heat transfer contribution.
Performance and Emissions Characteristics of Philippine CME-Diesel Blends
Authors: Quiros Edwin N. , Laguitao Jeffrey James C.
Published: August 2017

Deliberations in the Philippines are underway on the shift to 5% (B5) CME-diesel blend from the current B2 blend. In support to said deliberations, a fuel economy and gaseous emissions study of B1–B50 CME-diesel blends was conducted using an in-use Asian utility vehicle running on the Japanese 10–15 Mode drive cycle. Results show that adding CME up to 20% by volume (B20) has a small effect on the heating values, specific fuel consumption (SFC), mileage, and maximum power. Relative to neat diesel, the increase in SFC, and lower mileage and power beyond B20 were attributed to lower heating values at higher blends. CO was practically constant while THC and NOx generally decreased with increasing CME blends. The CO and THC trends were ascribed to overall lean mixtures and increased amount of oxygenated fuel at higher CME blends. The decreasing NOx trend needs further investigation as it seemed contrary to other studies. Based on these results, the shift to B5 would insignificantly affect fuel economy and likely lessen THC and NOx emissions. B20 yielded the most emissions reduction without performance loss.
Cost Benefit Analysis of Waste Heat to Power Option for Multistage Air Compressor
Authors: Tuo Hanfei , Shelat Maulik , Chakravarthy Vijayaraghavan
Published: August 2017

This paper summarizes results of a study conducted to minimize total cost of ownership of multistage air compressors by integrating it with compact and efficient off-the-shelf organic rankine power cycle units to recover low grade waste heat from inter-stage coolers with subsequent conversion to power. The paper also highlights challenges faced by the integration and provides guidance for future cost and technology targets for key components to make it a commercial scale reality. Various schemes for vaporization of the working fluid including direct and indirect as well as full or partial were explored. Also, in order to better understand interaction between cycle efficiency and capital cost of key components, design as well as operating parameters including evaporator approach temperature, compression stage suction temperature, number of compression stages and cooling water supply temperature were investigated. Configuration, size and hence the cost of evaporator/ inter-stage cooler was found to be one of the major factors governing the overall cost. Impact of various operating modes including turn-down and seasonal variations were also studied. Air flow and final discharge pressure from the multistage air compressor were kept constant throughout the study to facilitate a fair comparison.
Thermal and Electrical Performance of a Flat Plate Photovoltaic/Thermal Collector
Authors: Modrek Mohamad , Al-Alili Ali
Published: August 2017

Excess temperatures in photovoltaic panels may cause degradation in the panels’ electrical performance in short term. Moreover, photovoltaic cells may be damaged in the long term due to high operating temperatures. Therefore, photovoltaic thermal collectors (PVT)s have been proposed in order to solve these issues. PVT collectors allow the cooling of photovoltaic panels by heat extraction using a working fluid such as water or air. PVT collectors provide higher electrical output than standalone Photovoltaic (PV) panels while occupying a smaller area compared to a single solar thermal and a PV panel for the same capacity. In this study, the performance of a liquid cooled flat PVT collector under the climatic conditions of the United Arab Emirates is going to be investigated. The transient system simulation software (TRNSYS) is used to simulate the PVT system. The PVT system includes the PVT collectors, thermal storage tank, electrical storage, DC/AC inverter, pumps, and controllers. The effect of various design variables on the PVT electrical and thermal output is going to be studied. The design variables are the collector azimuth angle, slope of the collector, volume of the storage tank, and water mass flow rate through the PVT collector. The electrical and thermal outputs of the sized PVT system will be compared to that of a standalone PV panel electrical output and a standalone flat plate collector thermal output. Based on the obtained results, conclusions on the feasibility of using PVT collectors, under the weather conditions of the United Arab Emirates, will be deduced.