bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Si content on the cracking behavior of selective laser melted Al7050
Authors: Qi Ting , Zhu Haihong , Zeng Xiaoyan , Yin Jie
Published: July 2019

Purpose

It is a crucial issue to eliminate cracks for selective laser melting (SLM) 7xxx series aluminum alloy. This paper aims to study the effect of silicon content on the cracking behavior and the mechanism of eliminating crack of SLMed Al7050 alloy.

Design/methodology/approach

Six different silicon contents were added to the Al7050 powder. The crack density and crack count measuring from optical micrographs were utilized to judge the cracking susceptibility. The low melting phases analyzing from Jmatpro and the microstructure observing by EPMA and SEM were used to discuss the mechanism of eliminating the crack.

Findings

The cracking susceptibility of SLMed Al7050 alloy decreases with the increase of adding silicon content. When adding silicon, two new low-melting phases appeared: Mg2Si and Al5Cu2Mg8Si6. These low-melting phases offer much liquid feeding along the grain boundary and decrease the cracking susceptibility. Moreover, the grains are obviously refined after adding silicon. The fine grain can increase the total surface area of the grain boundary, which can reinforce the matrix and decrease the cracking susceptibility. High silicon content results in more low-melting phases and fine grains, which decreases the cracking susceptibility.

Originality/value

The investigation results can help to obtain crack-free SLMed Al7050 parts and deep knowledge on eliminating cracking mechanism of high-strength aluminum alloy fabricated by SLM.
Class and ambition in the status attainment process: A Spanish replication
Authors: Haller William , Portes Alejandro
Published: July 2019

There are two principal theoretical schools that seek to explain status outcomes in early adulthood: those focusing on intergenerational transmission of class privilege and those emphasizing individual characteristics, particularly ambition. The first may be called the structuralist school and the second the psycho‐social school, following the Wisconsin Model of Status Attainment. A second structuralist perspective, Segmented Assimilation, highlights transmission of socio‐economic status across immigrant generations, but emphasizes the positive role of co‐ethnic resources for upward mobility and preventing downward assimilation. We examine these alternative predictions using a large longitudinal sample of youths in Spain that includes both children of native parentage and children of immigrants. Spain possesses characteristics that make it uniquely suitable to examine these predictions. Results show that both family socio‐economic status and ambition, measured by adolescent educational aspirations and expectations, play important roles in educational and occupational attainment, but the influence of family status persists even after controlling for ambition. The influence of co‐ethnic nationalities disappears after these controls, except among Chinese and Filipino youths, a result consistent with segmented assimilation. Predictive models of status attainment yield identical results for children of immigrants and children of natives, indicating that in Spain, they have become part of a common youth universe. Theoretical and practical implications of the analysis are discussed.
One single large intramuscular dose of naloxone is effective and safe in suspected heroin poisoning
Authors: Harris Keith , Page Colin B , Samantray Sikta , Parker Lachlan , Brier Andrew JA , Isoardi Katherine Z
Published: July 2019

Objective

Naloxone is an established antidote for the treatment of heroin poisoning; however, dosing regimens vary widely, with a current trend towards small titrated intravenous dosing. This study aims to characterise naloxone use in the treatment of patients presenting with suspected heroin poisoning.

Methods

This was a retrospective review of poisoned patients presenting to a clinical toxicology unit in Brisbane from January 2015 to December 2017. Patient demographics, clinical effects, naloxone dosing, observation periods and complications were extracted from the patient's medical records.

Results

There were 117 presentations accounted for by 108 patients. Prehospital naloxone was provided to 57 (49%) patients, 46 of which received a standardised 1.6 mg i.m. dose. The remaining 60 (51%) patients received their first naloxone in hospital, with 58 (97%) receiving this by titrated i.v. doses. A subsequent naloxone infusion was required significantly more often in those treated with i.v. titrated naloxone compared to i.m. dose (27/69 [39%] vs 5/48 [10%], P = 0.0006). The need for parenteral sedation to manage acute behavioural disturbance following naloxone provision was rare (3/117 [3%]).

Conclusions

In this retrospective observational study, a single large i.m. dose of naloxone reversed the toxicity of suspected heroin overdose in the majority of patients. In addition, patients were less likely to require repeated intermittent doses or naloxone infusion than those treated solely with i.v. naloxone. Further comparison in a prospective study is warranted to validate these observations in confirmed heroin overdose. Requirement for sedation secondary to acute behavioural disturbance was rare regardless of the route.
Can Emergency Physician Gestalt “Rule In” or “Rule Out” Acute Coronary Syndrome: Validation in a Multicenter Prospective Diagnostic Cohort Study
Authors: Oliver Govind , Reynard Charlie , Morris Niall , Body Richard
Published: July 2019

Background

Chest pain is a common problem presenting to the emergency department (ED). Many decision aids and accelerated diagnostic protocols have been developed to help clinicians differentiate those needing admission from those who can be safely discharged. Some early evidence has suggested that clinician judgment or gestalt alone could be sufficient.

Objectives

Our aim was to externally validate whether emergency physician's gestalt could “rule in” or “rule out” acute coronary syndromes (ACS).

Methods

We performed a multicenter prospective diagnostic accuracy study including consenting patients presenting to the ED in whom the physician suspected ACS. At the time of arrival, clinicians recorded their perceived probability of ACS using a 5‐point Likert scale. The primary outcome was a diagnosis of ACS, defined as acute myocardial infarction or major adverse cardiac events within 30 days.

Results

A total of 1,391 patients were included; 240 (17.3%) had ACS. Overall, gestalt had fair diagnostic accuracy with a C‐statistic of 0.75 (95% confidence interval = 0.72 to 0.79). If ACS was “ruled out” in the 60 (4.3%) patients where clinicians perceived that the diagnosis was “definitely not” ACS, a sensitivity of 98.0% and negative predictive value of 95.0% could have been achieved. If ACS was only ruled out in patients who also had no electrocardiographic (ECG) ischemia and a normal initial cardiac troponin (cTn) concentration, 100.0% sensitivity and NPV could be achieved. However, this strategy only applied to 4.1% of patients. If patients with “probably not” ACS who had normal ECG and cTn were also ruled out (n = 418, 30.8%), sensitivity fell to 86.2% with 99.2% NPV. Using gestalt “definitely” ACS to rule in ACS gave a specificity of 98.5% and positive predictive value of 71.2%.

Conclusion

Clinician gestalt is not sufficiently accurate or safe to either rule in or rule out ACS as a decision‐making strategy. This study will enable emergency physicians to understand the limitations of our clinical judgment.
Experiences of interventions aiming to improve the mental health and well‐being of children and young people with a long‐term physical condition: A systematic review and meta‐ethnography
Authors: Shaw Liz , Moore Darren , Nunns Michael , Thompson Coon Jo , Ford Tamsin , Berry Vashti , Walker Erin , Heyman Isobel , Dickens Christopher , Bennett Sophie , Shafran Roz , Garside Ruth
Published: July 2019

Background

Children and young people with long‐term physical health conditions are at increased risk of experiencing mental health and well‐being difficulties. However, there is a lack of research that explores the experiences of and attitudes towards interventions aiming to improve their mental health and well‐being. This systematic review seeks to address this gap in the literature by exploring what children and young people with long‐term conditions, their caregivers, and health practitioners perceive to be important aspects of interventions aiming to improve their mental health and well‐being.

Methods

An information specialist searched five academic databases using predefined criteria for qualitative evaluations of interventions aiming to improve the mental health or well‐being of children with long‐term physical conditions. Reviewers also performed supplementary citation and grey literature searches. Two reviewers independently screened titles, abstracts, and full texts that met the inclusion criteria and conducted data extraction and quality assessment. Meta‐ethnography was used to synthesize the findings.

Results

Screening identified 60 relevant articles. We identified five overarching constructs through the synthesis: (a) Getting In and Staying In, (b) Therapeutic Foundation, (c) Social Support, (d) A Hopeful Alternative, and (e) Empowerment. The line of argument that links these constructs together indicates that when interventions can provide an environment that allows young people to share their experiences and build empathetic relationships, it can enable participants to access social support and increase feelings of hope and empowerment.

Conclusion

These findings may provide a framework to inform the development of mental health interventions for this population and evaluate existing interventions that already include some of the components or processes identified by this research. Further research is needed to establish which of the constructs identified by the line of argument are most effective in improving the mental well‐being of young people living with long‐term conditions.
Transferrin and H‐ferritin involvement in brain iron acquisition during postnatal development: impact of sex and genotype
Authors: Chiou Brian , Neely Elizabeth B. , Mcdevitt Dillon S. , Simpson Ian A. , Connor James R.
Published: July 2019

Iron delivery to the developing brain is essential for energy and metabolic support needed for processes such as myelination and neuronal development. Iron deficiency, especially in the developing brain, can result in a number of long‐term neurological deficits that persist into adulthood. There is considerable debate that excess access to iron during development may result in iron overload in the brain and subsequently predispose individuals to age‐related neurodegenerative diseases. There is a significant gap in knowledge regarding how the brain acquires iron during development and how biological variables such as development, genetics, and sex impact brain iron status. In this study, we used a mouse model expressing a mutant form of the iron homeostatic regulator protein HFE, (Hfe H63D), the most common gene variant in Caucasians, to determine impact of the mutation on brain iron uptake. Iron uptake was assessed using 59Fe bound to either transferrin or H‐ferritin as the iron carrier proteins. We demonstrate that at postnatal day 22, mutant mice brains take up greater amounts of iron compared with wildtype. Moreover, we introduce H‐ferritin as a key protein in brain iron transport during development and identify a sex and genotype effect demonstrating female mutant mice take up more iron by transferrin, whereas male mutant mice take up more iron from H‐ferritin at PND22. Furthermore, we begin to elucidate the mechanism for uptake using immunohistochemistry to profile the regional distribution and temporal expression of transferrin receptor and T‐cell immunoglobulin and mucin domain 2, the latter is the receptor for H‐ferritin. These data demonstrate that sex and genotype have significant effects on iron uptake and that regional receptor expression may play a large role in the uptake patterns during development.

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Open Science: This manuscript was awarded with the Open Materials Badge

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Cover Image for this issue: doi: 10.1111/jnc.14731.
How actionable are staff behaviours specified in policy documents? A document analysis of protocols for managing deteriorating patients
Authors: Smith Duncan , Sekhon Mandeep , Francis Jill J. , Aitken Leanne M.
Published: July 2019

Background

To optimise care of deteriorating patients, healthcare organisations have implemented rapid response systems including an “afferent” and “efferent” limb. Afferent limb behaviours include monitoring vital signs and escalating care. To strengthen afferent limb behaviour and reduce adverse patient outcomes, the National Early Warning Score was implemented in the UK. There are no published reports of how National Early Warning Score guidance has translated into trust‐level deteriorating patient policy and whether these documents provide clear, actionable statements guiding staff.

Aim

To identify how deteriorating patient policy documents provide “actionable” behavioural instruction for staff, responsible for actioning the afferent limb of the rapid response system.

Design

A structured content analysis of a national guideline and local policies using a behaviour specification framework.

Methods

Local deteriorating patient policies were obtained. Statements of behaviour were extracted from policies; coded using a behaviour specification framework: Target, Action, Context, Timing and Actor and scored for specificity (1 = present, nonspecific; 2 = present, specific). Frequencies and proportions of statements containing elements of the Target, Action, Context, Timing and Actor framework were summarised descriptively. Reporting was guided by the COREQ checklist.

Results

There were more statements related to monitoring than escalation behaviour (65% vs 35%). Despite high levels of clear specification of the action (94%) and the target of the behaviour (74%), context, timing and actor were poorly specified (37%, 37% and 33%).

Conclusion

Delay in escalating deteriorating patients is associated with adverse outcomes. Some delay could be addressed by writing local protocols with greater behavioural specificity, to facilitate actionability.

Relevance to clinical practice

Numerous clinical staff are required for an effective response to patient deterioration. To mitigate role confusion, local policy writers should provide clear specification of the actor. As the behaviours are time‐sensitive, clear specification of the time frame may increase actionability of policy statements for clinical staff.
Healthcare transition for adolescents and young adults with long‐term conditions: Qualitative study of patients, parents and healthcare professionals’ experiences
Authors: Coyne Imelda , Sheehan Aisling , Heery Emily , While Alison E.
Published: July 2019

Aim and objectives

To examine the needs and perspectives regarding healthcare transition for adolescents and young adults (AYAs) with the following long‐term conditions: diabetes, cystic fibrosis and congenital heart disease.

Background

Transition of AYAs within healthcare services has become increasingly important as more children are surviving into adulthood with long‐term conditions. Yet, limited empirical evidence exists regarding transition experiences.

Design

Qualitative study fulfilling the completed consolidated criteria for reporting qualitative studies criteria (see Appendix S1).

Methods

Semi‐structured interviews with AYAs aged 14–25 years (n = 47), parents (n = 37) and health professionals (n = 32), which was part of a larger mixed‐methods study. Sample was recruited from two children's hospitals and four general hospitals in Ireland.

Results

Transfer occurred between the ages of 16–early 20s years depending on the service. None of the hospitals had a transition policy, and transition practices varied considerably. Adolescents worried about facing the unknown, communicating and trusting new staff and self‐management. The transition process was smooth for some young adults, while others experienced a very abrupt transfer. Parents desired greater involvement in the transition process with some perceiving a lack of recognition of the importance of their role. In paediatric services, nurses reported following‐up adolescents who struggled with treatment adherence and clinic attendance, whereas after transfer, little effort was made to engage young adults if there were lapses in care, as this was generally considered the young adults’ prerogative.

Conclusions

The amount of preparation and the degree to which the shift in responsibility had occurred prior to transition appeared to influence successful transition for AYAs and their parents.

Relevance to clinical practice

Nurses in collaboration with the multidisciplinary team can help AYAs develop their self‐management skills and guide parents on how to relinquish responsibility gradually prior to transition.
Different type and dosage of heparin were not associated with the progression of coronary artery calcification in haemodialysis patients
Authors: Niu Qingyu , Yang Shuo , Gan Liangying , Zhao Huiping , Zuo Li
Published: July 2019

Aim

Several studies have verified that unfractionated heparin (UFH) and low molecular heparin (LWMH) can induce bone loss, and bone mineral density has been inversely associated with vascular calcification in some clinical researches. But few have focused on the relationship between types and dosages of heparin and the progression of vascular calcification. We observed the progression of coronary artery calcification (CAC) in maintenance haemodialysis (MHD) patients who were treated with UFH and LMWH.

Methods

This was a prospective prevalent cohort study of MHD patients. Computed tomography was performed at enrolment and 2 years after enrolment, and CAC score was obtained. Demographic and clinical data, baseline and time‐average laboratory indices were collected. Multiple linear regression and logistic regression were used to estimate the influencing factors of progression of CAC.

Results

In this study, (i) we initially enrolled 69 HD patients, and then 56 patients finished the follow‐up. (ii) Among the total 56 patients, 27 patients (48.2%) were treated with UFH, 14 (25.0%) with LMWH and 15 (26.8%) with both. The median baseline CAC scores of three groups (UFH, LMWH and both users) were 91.0 (1.0, 1052.0), 134.0 (0, 1292.0) and 250.5 (27.0, 1139.0), respectively, with no significant difference (P = 0.663); the median CAC progression scores were 42.0 (0, 364.0), 172.0 (7.0, 653.0) and 118.5 (0, 434.0), respectively, with no significant difference (P = 0.660). (iii) Pearson and spearman correlation analysis shown that the progression of CAC was not associated with cumulative dosage of heparin used. (iv) After adjusted for diabetes mellitus, time‐averaged intact parathyroid hormone, phosphate and alkaline phosphatase, logistic regression analysis showed using different types of heparin was not an independent risk factor for CAC progression; and multiple linear regression analysis showed that the type of heparin used was not associated with CAC progression.

Conclusion

There were no significant differences in the effects of the types and dosages of heparin on CAC progression in patients on haemodialysis.
Sacral nerve stimulation improves colonic inflammation mediated by autonomic‐inflammatory cytokine mechanism in rats
Authors: Guo Jie , Jin Haifeng , Shi Zhaohong , Yin Jieyun , Pasricha Trisha , Chen Jiande D. Z.
Published: July 2019

Background

Vagal nerve stimulation (VNS) was reported to have a therapeutic potential for inflammatory bowel disease (IBD). This study was designed to determine effects and mechanisms of SNS on colonic inflammation of in rodent models of IBD and compare the difference among SNS, VNS, and SNS plus VNS.

Methods

Intestinal inflammation in rats was induced by intrarectal administration of TNBS (2,4,6‐Trinitrobenzenesulfonic acid) on the first day. Five days after intrarectal TNBS, the rats were treated with sham‐VNS, VNS, Sham‐SNS, SNS, and SNS + VNS for 10 days. In another experiment, after 10 days of 4% DSS (dextran sodium sulfate) in drinking water, rats were treated with 10‐day sham‐SNS and SNS. Various inflammatory responses were assessed; mechanisms involving autonomic functions and inflammatory cytokines were investigated.

Key Results

(a) VNS, SNS, and VNS + SNS significantly and equally decreased the disease activity index and macroscopic scores, and normalized colon length; (b) IL‐10 was decreased by TNBS but increased with SNS, VNS, and SNS + VNS; pro‐inflammatory cytokines, IL‐6, IL‐17A, MCP‐1 and TNF‐α, were increased by TNBS but decreased with SNS, VNS, and SNS + VNS (P < .05); MPO activity was decreased by SNS, VNS, and SNS + VNS; (c) SNS, VNS, and SNS + VNS remarkably increased vagal activity that was suppressed by TNBS (P < .05); (d) smilar SNS effects were noted in rats with DSS‐induced colitis.

Conclusions & Inferences

SNS presents similar anti‐inflammatory effects as VNS by inhibiting pro‐inflammatory cytokines and increasing anti‐inflammatory cytokines via the autonomic pathway. Similar to VNS, SNS may also have a therapeutic potential for colonic inflammation.
Evaluating the President on Your Priorities: Issue Priorities, Policy Performance, and Presidential Approval, 1981–2016
Authors: Cavari Amnon
Published: July 2019

This article builds on the satisficing and attribution theories to propose a model of presidential approval where issue priorities moderate the association between presidents' policy performance evaluations and overall approval. The data include aggregate time‐series and cross‐sectional individual‐level data of presidential approval, presidential performance evaluations, and issue priorities from Reagan to Obama. The results demonstrate that people give more weight to the issues they prioritize, and therefore their evaluation of the president's performance on those issues matters more in their overall assessment of the president. The impact of issue priorities on approval varies by topic but is not further moderated by party affiliation. The results advance our understanding of the individual determinants of presidential approval and the role that issue priorities play in public opinion.
Americans’ Views of Voluntary Protective Actions Against Zika Infection: Conceptual and Measurement Issues
Authors: Johnson Branden B.
Published: July 2019

Understanding factors affecting decisions by people to protect themselves, or not, is critical to designing supportive communications. Here, threat, protective‐action, and stakeholder perceptions were evaluated for effects on mainland Americans’ behavioral intentions regarding Zika in April 2017, as postulated by the Protective Action Decision Model. Although all three perception types (including a novel resource sufficiency measure) affected intentions, these relationships varied widely depending upon the method used to measure adoption of actions (e.g., total count of all behaviors adopted vs. behavior‐specific analyses), the behaviors involved, and whether analysis focused on the full sample or only on people who had a reasonable opportunity to enact the behavior or who believed it relevant to their lives. There was a general contrast between mosquito control actions (removal of mosquito breeding areas and pesticide spraying) and travel‐related behaviors (avoiding travel to areas of local transmission of the virus, protecting oneself from mosquito bites after potential exposure, and practicing safe sex after potential exposure). Reported action or inaction during the 2016 mosquito season, and stages of behavior change, were both elicited in January–February 2017; both drove intentions in April 2017 for the upcoming season, although direct and indirect effects varied widely. Collectively these findings present theoretical, measurement, and practical implications for understanding, tracking, and promoting voluntary protective actions against hazards.
Superficial skin cancer therapy with Y‐90 microspheres: A feasibility study on patch preparation
Authors: Pashazadeh Ali , Landes Rainer , Boese Axel , Kreissl Michael C. , Klopfleisch Maurice , Friebe Michael
Published: July 2019

Background

Radiation therapy using beta particles is an interesting treatment for very superficial skin lesions. Due to their low penetration in tissue and rapid dose fall‐off, beta particles can protect underlying bony structures and surrounding healthy tissue while irradiating the skin tumor. In the current work, a simple method for the fabrication of a radioactive patch for use in skin cancer therapy based on a beta‐emitting isotope is presented.

Materials and methods

The beta radiation sources were Y‐90 microspheres currently used for catheter‐based radioembolization of unresectable liver tumors. The microspheres were filtered through a syringe filter to trap them on the cellulose nitrate paper of the filter and create a radioactive patch. In the current study, to avoid the need for a hot laboratory, the experiment was done using nonradioactive microspheres. An optical microscope was used to verify the distribution of the particles on the filter paper.

Results

Visual evaluation of the patches showed that using the proposed method, therapeutic skin patches with a fairly uniform distribution of microspheres can be created.

Conclusion

The proposed simple method may be used in creating radiotherapeutic patches using Y‐90 microspheres for radiation therapy of thin skin lesions located close to sensitive structures.
Using Cognitive Neuroscience Principles to Design Efficient Reading Programs: Case Studies from India and Malawi Cognitive Neuroscience to Design Literacy Programs
Authors: Iyengar Radhika
Published: July 2019

The hidden crisis in education has come to light since the past decade. Millions of school-going children remain illiterate, even after spending 2-3 years in school. This paper explores a cognitive neuroscience driven method to improve children’s reading in two local languages--Chichewa (Malawi) and Telugu (Telangana, India). The paper first presents the science behind how children learn using this science-driven model. It then presents the process of contextualization of this literacy method for Malawi and Telangana, India. The contextualization and adaptation processes lead to some generalized principles that could be applied to other local language literacy programs. The study looks at sequencing of letters, font size and type, teacher training modalities as well as classroom delivery processes, which are all key components for any early literacy intervention. The study also focuses on cost-cutting measures to aid in full implementation and scale-up for a low resourced educational setting.
Assessment and management of cough among patients with lung cancer in a radiotherapy department in China: a best practice implementation project
Authors: Zhang Lanfang , Wu Yanni , Du Mengya , He Lian , Xie Guozhu , Wang Hongmei , Zhou Chunlan , Chen Peijuan
Published: July 2019

Objectives:

This project aimed to implement an evidence-based practice to assess and manage lung cancer-associated cough, thereby relieving patients’ physical pain and psychological challenges and improving their quality of life.

Introduction:

Cough is one of the most common symptoms experienced by patients with lung cancer. If a cough is not proactively managed, patients may develop decreased compliance with treatments and experience a reduced quality of life. Cough assessment and management are essential components of nursing practice that should include evidence-based interventions.

Methods:

Seven evidence-based audit criteria were developed from current evidence. The JBI Practical Application of Clinical Evidence System (PACES) was used to perform a baseline audit on 30 patients and 20 nurses in the Department of Radiotherapy of Nanfang Hospital. The Getting Research into Practice (GRiP) component of PACES was used to identify barriers, strategies, resources and outcomes. Following implementation of strategies to improve compliance, a post-audit was conducted using the same sample size and audit criteria.

Results:

The seven evidence-based audit criteria were as follows: 1) Clinicians have received training on the assessment and management of lung cancer-associated cough; 2) In patients with lung cancer-associated cough, a comprehensive assessment was conducted to identify any co-existing causes linked to cough; 3) Any reversible causes of cough were treated according to evidence-based guidelines; 4) A validated scale was used to assess the frequency and severity of cough and distress experienced by the patients; 5) Patients (and their caregivers) have received education regarding management of cough; 6) Patients (and their caregivers) have received training on cough suppression exercises; 7) For symptomatic therapy, a stepwise approach was followed according to evidence-based guidelines. The baseline results showed that compliance rates were 0% for criteria 1, 4 and 5; 70% for criterion 6; 80% for criterion 7; 90% for criterion 3 and 93% for criterion 2. The implementation of strategies to increase compliance with best practice, including establishing training and education programs for nursing staff and patients, utilizing some validated scales to assess the frequency and severity of cough and the distress caused to the patients, and establishing a quality control team to supervise implementation of the assessment and management of cough, achieved ≥ 93% compliance rate for all seven audit criteria.

Conclusion:

An evidence-based and nurses-oriented best practice for cough assessment and management was successfully established among patients with lung cancer-associated cough.
Duration and determinants of Chagas latency: an etiology and risk systematic review protocol
Authors: Henao-Martínez Andrés F. , Chadalawada Sindhu , Villamil-Gomez Wilmer E. , DeSanto Kristen , Rassi Anis , Franco-Paredes Carlos
Published: July 2019

Objective:

The objective of this systematic review is to explore and discuss the latency duration among asymptomatic people with chronic Chagas disease.

Introduction:

Studies estimate the latency period of Chagas disease to be approximately 10–30 years. However, new findings may indicate that this latency period is shorter and depends on the presence of clinical factors. This systematic review protocol will explore the duration and factors affecting this latency period to inform treatment, with the potential of improving outcomes.

Inclusion criteria:

Eligible studies will include asymptomatic people with indeterminate Chagas disease confirmed through positive serologic testing and the absence of structural cardiomyopathy with no heart failure symptoms and normal electrocardiography results. Studies that involve a longitudinal observation period of participants will be considered. This period must start from the acute acquisition of the infection or an already established indeterminate form of the disease until the development of a primary or secondary cardiac outcome.

Methods:

The following electronic databases will be searched: MEDLINE, Embase, Cochrane Library, Web of Science Core Collection and LILACS. The search will include the following concepts: Chagas disease, latency duration and determinants of the Chagas latency period. The languages will be restricted to English, Spanish and Portuguese. Two reviewers will review the selected studies for methodological quality using critical appraisal tools and conduct data extraction. Studies will, where possible, be pooled in a statistical meta-analysis. All data will be presented and synthesized through tables, summaries, figures and charts.

Systematic review registration number:

PROSPERO CRD42019118019
Muscle specific kinase protects dystrophic mdx mouse muscles from eccentric contraction‐induced loss of force‐producing capacity
Authors: Trajanovska S. , Ban J. , Huang J. , Gregorevic P. , Morsch M. , Allen D. G. , Phillips W. D.
Published: July 2019

Key points

Adeno‐associated viral vector was used to elevate the expression of muscle specific kinase (MuSK) and rapsyn (a cytoplasmic MuSK effector protein) in the tibialis anterior muscle of wild‐type and dystrophic (mdx) mice.

In mdx mice, enhanced expression of either MuSK or rapsyn ameliorated the acute loss of muscle force associated with strain injury.

Increases in sarcolemmal immunolabelling for utrophin and β‐dystroglycan suggest a mechanism for the protective effect of MuSK in mdx muscles.

MuSK also caused subtle changes to the structure and function of the neuromuscular junction, suggesting novel roles for MuSK in muscle physiology and pathophysiology.

Muscle specific kinase (MuSK) has a well‐defined role in stabilizing the developing mammalian neuromuscular junction, but MuSK might also be protective in some neuromuscular diseases. In the dystrophin‐deficient mdx mouse model of Duchenne muscular dystrophy, limb muscles are especially fragile. We injected the tibialis anterior muscle of 8‐week‐old mdx and wild‐type (C57BL10) mice with adeno‐associated viral vectors encoding either MuSK or rapsyn (a cytoplasmic MuSK effector protein) fused to green fluorescent protein (MuSK‐GFP and rapsyn‐GFP, respectively). Contralateral muscles injected with empty vector served as controls. One month later mice were anaesthetized with isoflurane and isometric force‐producing capacity was recorded from the distal tendon. MuSK‐GFP caused an unexpected decay in nerve‐evoked tetanic force, both in wild‐type and mdx muscles, without affecting contraction elicited by direct electrical stimulation of the muscle. Muscle fragility was probed by challenging muscles with a strain injury protocol consisting of a series of four strain‐producing eccentric contractions in vivo. When applied to muscles of mdx mice, eccentric contraction produced an acute 27% reduction in directly evoked muscle force output, affirming the susceptibility of mdx muscles to strain injury. mdx muscles overexpressing MuSK‐GFP or rapsyn‐GFP exhibited significantly milder force deficits after the eccentric contraction challenge (15% and 14%, respectively). The protective effect of MuSK‐GFP in muscles of mdx mice was associated with increased immunolabelling for utrophin and β‐dystroglycan in the sarcolemma. Elevating the expression of MuSK or rapsyn revealed several distinct synaptic and extrasynaptic effects, suggesting novel roles for MuSK signalling in muscle physiology and pathophysiology.
The dilemma in the management of haemodynamically stable pulmonary embolism with right heart thrombus
Authors: Rai Manoj P , Herzallah Khadar , Alratroot Ahmad , Laird-Fick Heather
Published: July 2019

Right ventricular thrombus (RVT) can be life-threatening, since it has the potential to embolise and cause saddle pulmonary embolism (PE). We present a patient who initially presented with haemodynamically stable PE with evidence of RVT on echocardiogram. She was placed on heparin drip; however, she later developed cardiac arrest and died due to embolisation of RVT to the pulmonary vasculature. Although management of haemodynamically stable PE in patients with RVT is still a matter of debate,1given the outcome we suggest that thrombolysis or emergent embolectomy at the presentation, in this case, may have had a favourable outcome.
Revealing a rare inflammatory oral manifestation in a 6-year-old child
Authors: Routray Samapika , Adhya Amit Kumar , John Joseph , Dikhit Punit
Published: July 2019

A 6-year-old child with an episodic history of ulcerations over buccal mucosa was found to have severe inflammation on the palatal aspect of permanent first molars with grade 2 mobility bilaterally. Radiographical features were suggestive of bone loss around permanent molars extending to the distal aspect of the deciduous first molars. The clinical and radiographical findings were indicative of periodontal degeneration without any apparent cause visible intraorally. Further biopsy was done from the rashes present on the malar prominences, which showed nodular aggregates of atypical cells in superficial dermis. These large histiocytic cells with vesicular nuclei and nuclear grooves were immunopositive for CD1a and S100, concluding the diagnosis of Langerhans cell histiocytosis. For treatment, patient was referred to Department of Haemato-oncology and chemotherapy was suggested as per protocol.
Awareness of risk factors and warning symptoms and attitude towards gastric cancer screening among the general public in China: a cross-sectional study
Authors: Liu Qi , Zeng Xi , Wang Wen , Huang Ruo-lin , Huang Yan-jin , Liu Shan , Huang Ying-hui , Wang Ying-xin , Fang Qing-hong , He Guoping , Zeng Ying
Published: July 2019

Objectives

This study aimed to assess the knowledge of risk factors and warning symptoms and attitude towards gastric cancer screening among the general population in China.

Setting

Hunan province, China

Participants

Individuals aged older than 18 years were recruited using a cluster sampling method.

Design

A cross-sectional study, and a pretested structured questionnaire was used to assess participants’ awareness of gastric cancer.

Primary and secondary outcome measures

Knowledge level of risk factors and warning symptoms of gastric cancer, gastric cancer screening attitude, sociodemographic factors associated with gastric cancer knowledge and screening behaviour.

Results

This study comprised 1200 participants with a mean age of 40.31 (SD 16.73) years, of whom 622 (51.8%) were women. The mean score for gastric cancer knowledge was 8.85/22 (SD 6.48). There were 47.0% of the participants who had a low knowledge level about the risk factors and warning symptoms of gastric cancer. In total, 83.8% believed screening is helpful for early detection of gastric cancer, and 15.2% had undergone gastric cancer screening. The most common reason for not undergoing screening was having ‘no symptoms’ (63.0%), followed by ‘fear of undergoing gastroscopy’ (38.1%). Independent factors related to lower knowledge levels included male sex, living in rural areas, lower educational level, working as a farmer and without a family history of gastric cancer (p<0.05). Factors independently associated with screening behaviour included white-collar employment, higher income and having upper gastrointestinal tract diseases (p<0.05).

Conclusions

In China, people have poor knowledge about risk factors and warning symptoms of gastric cancer, but a majority have a positive attitude towards the benefits of gastric cancer screening. Being asymptomatic and having a fear of gastroscopy were the main self-reported reasons for not undergoing screening. These results highlight the urgent need for educational campaigns to improve gastric cancer awareness.
Early roots of sexual-orientation health disparities: associations between sexual attraction, health and well-being in a national sample of Australian adolescents
Authors: Perales Francisco , Campbell Alice
Published: July 2019

Background

Research documents substantial adolescent health disparities by sexual orientation, but studies are confined to a small number of countries—chiefly the USA. We provide first-time evidence of associations between sexual orientation and adolescent health/well-being in a new country—Australia. We also add to knowledge by examining health/well-being outcomes not previously analysed in national samples, considering adolescents reporting no sexual attractions, and rank-ordering sexual-orientation health disparities by magnitude.

Methods

Data from an Australian national probability sample of 14/15 years old (Longitudinal Study of Australian Children, n=3318) and regression models adjusted for confounding and for multiple comparisons were used to examine the associations between sexual attraction and 30 outcomes spanning multiple domains of health/well-being—including socio-emotional functioning, health-related quality of life, depressive symptoms, health-related behaviours, social support, self-harm, suicidality, victimisation, self-concept, school belonging and global health/well-being assessments.

Results

Lesbian, gay, bisexual and questioning adolescents displayed significantly worse health/well-being than their heterosexual peers in all outcomes (p<0.05). The magnitude of the disparities ranged between 0.13 and 0.75 SD, and was largest in the domains of self-harm, suicidality, peer problems and emotional problems. There were fewer differences between the heterosexual and no-attraction groups. Worse outcomes were observed among both-sex-attracted adolescents compared with same-sex-attracted adolescents, and sexual-minority girls compared with sexual-minority boys.

Conclusions

Consistent with the minority stress model and recent international scholarship, sexual-minority status is an important risk factor for poor adolescent health/well-being across domains in Australia. Interventions aimed at addressing sexual-orientation health disparities within Australian adolescent populations are urgently required.
Effects of resveratrol postconditioning on cerebral ischemia in mice: role of the sirtuin-1 pathway
Authors: Grewal Amarjot Kaur , Singh Nirmal , Singh Thakur Gurjeet
Published: July 2019

Evidence has demonstrated that resveratrol preconditioning exhibits neuroprotection against cerebral ischemia–reperfusion (IR) injury. The current investigation aimed to explore whether pharmacological postconditioning, by administering resveratrol, after a sustained ischemia and prior to prolonged reperfusion abrogates cerebral IR injury. Cerebral IR-induced injury mice model was employed in this study to evaluate the neuroprotective effects of pharmacological postconditioning with resveratrol (30 mg/kg; i.p.) administered 5 min before reperfusion. We administered sirtinol, a SIRT1/2 selective inhibitor (10 mg/kg; i.p.) 10 min before ischemia (17 min) and reperfusion (24 h), to elucidate whether the neuroprotection with resveratrol postconditioning depends on SIRT1 activation. Various biochemical and behavioural parameters and histopathological changes were assessed to examine the effect of pharmacological postconditioning. Infarct size is estimated using TTC staining. It was established that resveratrol postconditioning abrogated the deleterious effects of IR injury expressed with regard to biochemical parameters of oxidative stress (TBARS, SOD, GSH), acetylcholinesterase activity, behavioural parameters (memory, motor coordination), infarct size, and histopathological changes. Sirtinol significantly reversed the effect of resveratrol postconditioning. We conclude that induced neuroprotective benefits of resveratrol postconditioning may be the consequence of SIRT1 activation and resveratrol can be considered, for further studies, as potential agent inducing pharmacological postconditioning in clinical situations.
Mechanism of atrazine resistance in atrazine- and HPPD inhibitor-resistant Palmer amaranth (Amaranthus palmeri S. Wats.) from Nebraska
Authors: Chahal Parminder S. , Jugulam Mithila , Jhala Amit J.
Published: July 2019

Palmer amaranth (Amaranthus palmeri S. Wats.) is one of the most problematic weed species in agronomic crops in the United States. A Palmer amaranth biotype multiple-resistant to atrazine and 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors was reported in a seed corn production field in Nebraska. Rapid detoxification mediated by cytochrome P450 monooxygenases and increased HPPD gene expression were reported as the mechanisms of mesotrione resistance in atrazine- and HPPD inhibitor-resistant Palmer amaranth biotype from Nebraska; however, the mechanism of atrazine resistance is unknown. The objectives of this study were to investigate target site or non-target site based mechanisms conferring atrazine resistance in Palmer amaranth from Nebraska. 14C-atrazine absorption and translocation studies revealed that reduced atrazine absorption or translocation were not involved as one of the mechanisms of atrazine resistance. Instead, greater 14C-atrazine absorption and recovery in treated leaves were observed in resistant compared with susceptible Palmer amaranth. No known mutations including Ser264Gly substitution in the psbA gene causing target site based atrazine resistance were observed. However, the parent 14C-atrazine was metabolized rapidly <4 h after treatment in resistant plants, conferring enhanced atrazine metabolism as the mechanism of resistance.
An elementary introduction to the geometry of quantum states with pictures
Authors: Avron J. , Kenneth O.
Published: July 2019

This is a review of the geometry of quantum states using elementary methods and pictures. Quantum states are represented by a convex body, often in high dimensions. In the case of [Formula: see text] qubits, the dimension is exponentially large in [Formula: see text]. The space of states can be visualized, to some extent, by its simple cross sections: Regular simplexes, balls and hyper-octahedra. a When the dimension gets large, there is a precise sense in which the space of states resembles, almost in every direction, a ball. The ball turns out to be a ball of rather low purity states. We also address some of the corresponding, but harder, geometric properties of separable and entangled states and entanglement witnesses.

“All convex bodies behave a bit like Euclidean balls.”

Keith Ball
The Orlicz–Minkowski problem for measure in ℝn and Orlicz geominimal measures
Authors: Mou Shuang , Zhu Baocheng
Published: July 2019

For a measure [Formula: see text] on [Formula: see text] with density that has a positive degree of homogeneous and a positive degree of concavity, we study the Orlicz–Minkowski problem for such general measure [Formula: see text] and show the existence of the even Orlicz–Minkowski problem for [Formula: see text]. We also introduce the general Orlicz geominimal [Formula: see text]-measures and show the existence of the Orlicz-Petty bodies for the general measure [Formula: see text], and hence prove the continuity of the general Orlicz geominimal [Formula: see text]-measure.
Transient nanofluid squeezing cooling process using aluminum oxide nanoparticle
Authors: Tlili Iskander , Moradi R. , Barzegar Gerdroodbary M.
Published: July 2019

Computational studies have been widely applied for the thermal evaluation of the nanomaterial thermal feature in different industrial and scientific issues. The squeezed flow and heat transfer features for Al2O3-water nanofluid among analogous plates are investigated using the GOHAM and its validity is verified by comparison with existing numerical results. Novel aspects of Brownian motion and thermal force were accounted in the simulation of nanomaterial flow within parallel plate. Analytical investigation has been done for diverse governing factors namely: the squeeze, chemical reaction factors and Eckert number. The obtained outcomes show that [Formula: see text] has direct relationship with absolute values of squeeze factor. Nu increases for large Eckert number and absolute values of squeeze number.
A non-canonical scalar field cosmological model: Stability and bifurcation analysis
Authors: Mishra Sudip , Chakraborty Subenoy
Published: July 2019

In this work, cosmological implications of a non-canonical scalar field model have been studied in the background of homogeneous and isotropic flat FLRW spacetime by using dynamical system analysis. By suitable change of variables, the field equations are transformed to an autonomous system and the stability of the system of critical points are examined. For hyperbolic critical points, the analysis of the system is done by using Hartman–Grobman theorem, while the center manifold theory is used to study non-hyperbolic critical points. It is found that the parameters in the autonomous system play a crucial role for phase transition of the Universe. Finally, possible bifurcation scenarios are discussed to identify the point of phase transition.