bluuebunny/crossref_metadata_2025 huggingface dataset:
Digital Platforms and Supervisory Feedback to Graduate Student Clinicians
Authors: Lorio Ciera M. , Delehanty Abigail D. , Woods Juliann J.
Published: April 2016

Portable electronic devices are becoming more prevalent in the field of speech-language pathology, from assessment and intervention to supervision. This study examined the use of various forms of supervisory feedback provided through digital platforms on a detailed fidelity checklist to five first-year graduate student clinicians participating in a community-based practicum. Three feedback conditions were compared: (a) e-mails sent after intervention sessions, (b) text messaging during intervention sessions, and (c) no e-mails or text messaging feedback. All forms of feedback were supplemented by an e-mail graph depicting progress on the fidelity checklist. Graduate student clinicians found all forms of digital feedback to be beneficial, with specific, immediate feedback being preferred. The fidelity checklist supported the graduate student clinicians' implementation of intervention techniques as well as the supervisors' ability to provide detailed feedback. Implications for future research and suggestions for supervision of graduate student clinicians are discussed.
Extended Kalman filter‐based method for inter‐turn fault detection of the switched reluctance motors
Authors: Khayam Hoseini Seyed Reza , Farjah Ebrahim , Ghanbari Teymoor , Givi Hadi
Published: April 2016

Switched reluctance motors (SRMs) are extensively utilised in electric vehicles (EVs) due to some outstanding capabilities such as rugged and fault tolerant structure. Since the excitation of the phases is performed independently in the SRM, the motor could continue operation even in case of fault occurrence in one of the phases by disabling the faulty phase. However, to improve the reliability of the SRM for EV applications, an efficient fault diagnosis approach should be employed. In this study, an on‐line method for detection of winding inter‐turn short‐circuit fault in the SRMs is presented. The proposed technique is based on a model, in which the extended Kalman filter is utilised. The method achieves a fast response, thus, the remedial strategies could be employed at the initial moments after fault occurrence. The proposed method is simple to implement and reliable in practice. The performance of the proposed approach is verified using some simulations and experiments. The results confirm high capability of the method in different conditions.
Primary Leiomyosarcoma of the Mandibular Alveolar Mucosa of a 12-Year-Old Child from Ethiopia: A Case Report
Authors: Kenea TewodrosTefera , Kebede BetelAbebe , Gozjuze FekaduMesele , Kiros Hagos , Wilde Frank
Published: April 2016

Leiomyosarcomas (LMSs) are rare malignant mesenchymal tumors which show smooth-muscle differentiation. Most LMSs involving the oral tissues primarily affect the maxillary sinus, the maxillary or mandibular bone. We present a case of LMS of the mandibular alveolar mucosa, arising in a 12-year-old male child from Ethiopia. A malignant spindle cell-like neoplasm was diagnosed on clinical and radiographic findings as well as on incisional biopsy. The tumor was resected with wide margins. The following histopathologic examination with additional immunohistochemical studies secured the diagnosis LMS. Microscopically, the spindle-shaped tumor cells were arranged in an interlacing fascicular pattern and contained oval to elongated, blunt-ended (cigar-shaped) nuclei. The immunohistochemical examination showed immunoreactive tumor cells for vimentin, actin, desmin, and H-caldesmon, which is pathognomonic for LMS. Immunohistochemical studies are mandatory to differentiate the LMS from other similar spindle cell neoplastic lesions. Radical resection with safety margins and a lifelong periodic follow-up has to be recommended.
A Comparison of Magnetic Resonance Imaging Muscle Fat Content in the Lumbar Paraspinal Muscles with Patient-Reported Outcome Measures in Patients with Lumbar Degenerative Disk Disease and Focal Disk Prolapse
Authors: Bhadresha Ashwin , Lawrence Owen John , McCarthy Michael J. H.
Published: April 2016

Study Design

Retrospective study.

Objectives

To assess the fatty atrophy of the lumbar paraspinal muscles (LPMs) as determined using magnetic resonance imaging in patients with lumbar degenerative disk disease (DDD) and focal disk herniation and to determine if fatty atrophy is associated with patient-reported outcome measures (PROMS).

Methods

One hundred sixty-five patients with lumbar DDD were identified from a PROMS database of >1,500 patients. These patients were divided into two study groups: DDD alone ( n= 58) and DDD with disk herniation ( n= 107). A grid was randomly applied to the axial scans at the L3–L4, L4–L5, and L5–S1 levels. The muscle-to-fat ratio of the LPMs was recorded and compared with PROMS data. Subcutaneous fat thickness at each level was also measured.

Results

This study found no difference in the muscle-to-fat ratio between the DDD and disk herniation groups. There was no association between the muscle-to-fat ratio and PROMS data in either group. There was significantly more subcutaneous fat at all levels in the DDD group as compared with the disk prolapse group. In DDD and disk prolapses, subcutaneous fat was thicker in women ( p = 0.013 and 0.001). In patients with DDD, more subcutaneous fat was associated with disability ( p < 0.001). Muscle content of erector spinae and multifidus negatively correlated with increasing age in both groups at the L3–L4 level.

Conclusions

Muscle fat content in the LPM does not appear to relate to PROMS. Muscle content decreases with age. Those with low back pain (DDD) have greater subcutaneous fat thickness.
Note: Near infrared interferometric silicon wafer metrology
Authors: Choi M. S. , Park H. M. , Joo K. N.
Published: April 2016

In this investigation, two near infrared (NIR) interferometric techniques for silicon wafer metrology are described and verified with experimental results. Based on the transparent characteristic of NIR light to a silicon wafer, the fiber based spectrally resolved interferometry can measure the optical thickness of the wafer and stitching low coherence scanning interferometry can reconstruct entire surfaces of the wafer.
Analysis of reaction between c+a and -c+a dislocations in GaN layer grown on 4-inch Si(111) substrate with AlGaN/AlN strained layer superlattice by transmission electron microscopy
Authors: Sugawara Yoshihiro , Ishikawa Yukari , Watanabe Arata , Miyoshi Makoto , Egawa Takashi
Published: April 2016

The behavior of dislocations in a GaN layer grown on a 4-inch Si(111) substrate with an AlGaN/AlN strained layer superlattice using horizontal metal-organic chemical vapor deposition was observed by transmission electron microscopy. Cross-sectional observation indicated that a drastic decrease in the dislocation density occurred in the GaN layer. The reaction of a dislocation (b=1/3[-211-3]) and anothor dislocation (b =1/3[-2113]) to form one dislocation (b =2/3[-2110]) in the GaN layer was clarified by plan-view observation using weak-beam dark-field and large-angle convergent-beam diffraction methods.
Distinctive mapping of strain and quantum size effects using depth-resolved photoluminescence in ZnO nanoneedles
Authors: Hwang Hyeong-Yong , Baek Hyeonjun , Yi Gyu-Chul , Kim Hyoung-Chan , Jho Young-Dahl
Published: April 2016

In order to locate the spatially resolved influence of the strain, carrier localization, and quantum size effect (QSE) in tapered ZnO nanoneedles (NNs), the photoluminescence (PL) was measured as a function of the incident laser angle θ from 0∘ (normal to a surface) to 85∘. With increasing θ, the excitation point is spatially restricted along the axis of the NNs and varies from the ZnO buffer/sapphire interface to the tips of the NNs. In this way, we identified a strain-induced blue-shift of 25.3 meV at the ZnO buffer/sapphire interface, which corresponds to a tensile strain of 0.319%. The influence of strain and the concomitant indications of carrier localization decreased as the excitation point moved to a higher location along the NNs with increasing θ whereas the QSE revealed an abrupt blue-shift near the tips of the NNs. Furthermore, time-resolved PL measurement as a function of the excitation angle was used to distinguish the strain effect from the QSE. We observed two spatially competing tendencies: (1) the decay times are influenced by the increase in the interfacial strain and (2) the decay times are influenced by the decrease in the diameter-dependent QSE near the tips of the tapered ZnO NNs.
Hafnium dioxide as a dielectric for highly-sensitive waveguide-coupled surface plasmon resonance sensors
Authors: Tiwari Kunal , Sharma Suresh C. , Hozhabri Nader
Published: April 2016

Hafnium dioxide has been recognized as an excellent dielectric for microelectronics. However, its usefulness for the surface plasmon based sensors has not yet been tested. Here we investigate its usefulness for waveguide-coupled bi-metallic surface plasmon resonance sensors. Several Ag/HfO2/Au multilayer structure sensors were fabricated and evaluated by optical measurements and computer simulations. The resulting data establish correlations between the growth parameters and sensor performance. The sensor sensitivity to refractive index of analytes is determined to be Sn=∂θSPR∂n≥470. The sensitivity data are supported by simulations, which also predict 314 nm for the evanescent field decay length in air.
Surface plasmon transmission through discontinuous conducting surfaces: Plasmon amplitude modulation by grazing scattered fields
Authors: Mayoral-Astorga L. A. , Gaspar-Armenta J. A. , Ramos-Mendieta F.
Published: April 2016

We have studied numerically the diffraction of a surface plasmon polariton (SPP) when it encounters a wide multi-wavelength slit in conducting films. As a jump process a SPP is excited beyond the slit by wave scattering at the second slit edge. The exciting radiation is produced when the incident SPP collapses at the first slit edge. We have found that the transmitted SPP supports inherent and unavoidable interference with grazing scattered radiation; the spatial modulation extends to the fields in the diffraction region where a series of low intensity spots arises. We demonstrate that the SPP generated on the second slab depends on the frequency but not on the wave vector of the collapsed SPP; a SPP is transmitted even when the two metals forming the slit are different. The numerical results were obtained using the Finite Difference Time Domain (FDTD) method with a grid size λ/100.
Effect of strain rate and dislocation density on the twinning behavior in tantalum
Authors: Florando Jeffrey N. , El-Dasher Bassem S. , Chen Changqiang , Swift Damian C. , Barton Nathan R. , McNaney James M. , Ramesh K. T. , Hemker Kevin J. , Kumar Mukul
Published: April 2016

The conditions which affect twinning in tantalum have been investigated across a range of strain rates and initial dislocation densities. Tantalum samples were subjected to a range of strain rates, from 10−4/s to 103/s under uniaxial stress conditions, and under laser-induced shock-loading conditions. In this study, twinning was observed at 77K at strain rates from 1/s to 103/s, and during laser-induced shock experiments. The effect of the initial dislocation density, which was imparted by deforming the material to different amounts of pre-strain, was also studied, and it was shown that twinning is suppressed after a given amount of pre-strain, even as the global stress continues to increase. These results indicate that the conditions for twinning cannot be represented solely by a critical global stress value, but are also dependent on the evolution of the dislocation density. In addition, the analysis shows that if twinning is initiated, the nucleated twins may continue to grow as a function of strain, even as the dislocation density continues to increase.
Factors affecting turnover intentions among public hospital doctors in a middle-level city in central China
Authors: Zhang Fengfan , Luo Zhenni , Chen Ting , Min Rui , Fang Pengqian
Published: April 2016

Objective The aim of the present study was to explore prominent factors affecting turnover intentions among public hospital doctors in urban areas, particularly in Xiangyang City, Hubei Province, a middle-level city in central China. Methods Questionnaires were used to collect data from 284 public hospital doctors. Pearson’s Chi-squared was used to assess whether sociodemographic and other factors were related to the turnover intentions of public hospital doctors. Binary logistic regression was performed to determine the significant factors that influence turnover intentions. Results The analysis revealed that 28.2% of public hospital doctors intended to leave the hospital where they were currently employed. Dissatisfaction with working conditions and hospital management processes, as well as work pressures, were significant factors contributing to the turnover intentions of public hospital doctors. Conclusion Research into turnover intentions indicates that public hospital doctors surveyed in urban China give greater weight to their professional environment and career development rather than salary in their employment decisions. What is known about the topic? Turnover of medical staff is a concern to hospital administrators because it is costly and detrimental to organisational performance and quality of care. Most studies have focused on the effects of individual and organisational factors on nurses’ intentions to leave their employment. Income dissatisfaction was one of the determining factors of turnover intentions in previous studies. What does this paper add? The satisfaction of public hospital doctors with regard to income is not a determining factor of turnover intentions. In contrast with findings of previous studies, the doctors in public hospitals in urban China in the present study gave greater weight to their professional environment and career development in their employment decisions. What are the implications for practitioners? The findings suggest that health service managers and policy makers should pay greater attention to the factors affecting public hospital doctors’ turnover intentions. This study will be useful for optimising public hospital management and minimising the turnover of doctors in China.
10 Best resources on… intersectionality with an emphasis on low- and middle-income countries
Authors: Larson Elizabeth , George Asha , Morgan Rosemary , Poteat Tonia
Published: April 2016

Intersectionality has emerged as an important framework for understanding and responding to health inequities by making visible the fluid and interconnected structures of power that create them. It promotes an understanding of the dynamic nature of the privileges and disadvantages that permeate health systems and affect health. It considers the interaction of different social stratifiers (e.g. ‘race’/ethnicity, indigeneity, gender, class, sexuality, geography, age, disability/ability, migration status, religion) and the power structures that underpin them at multiple levels. In doing so, it is a departure from previous health inequalities research that looked at these forms of social stratification in isolation from one another or in an additive manner. Despite its potential use and long history in other disciplines, intersectionality is uncommonly used in health systems research in low- and middle-income countries (LMICs). To orient readers to intersectionality theory and research, we first define intersectionality and describe its role in public health, and then we review resources on intersectionality. We found that applications in public health mostly increased after 2009, with only 14 out of 86 articles focused on LMICs. To arrive at 10 best resources, we selected articles based on the proportion of the article that was devoted to intersectionality, the strength of the intersectionality analysis, and its relevance to LMICs. The first four resources explain intersectionality as a methodology. The subsequent six articles apply intersectionality to research in LMIC with quantitative and qualitative analysis. We provide examples from India, Swaziland, Uganda and Mexico. Topics for the studies range from HIV, violence and sexual abuse to immunization and the use of health entitlements. Through these 10 resources, we hope to spark interest and open a needed conversation on the importance and use of intersectional analysis in LMICs as part of understanding people-centred health systems.
The Use of Smartphones for Health Research
Authors: Dorsey E. Ray , “Yvonne” Chan Yu-Feng , McConnell Michael V. , Shaw Stanley Y. , Trister Andrew D. , Friend Stephen H.
Published: April 2016

Because of their growing popularity and functionality, smartphones are increasingly valuable potential tools for health and medical research. Using ResearchKit, Apple’s open-source platform to build applications (“apps”) for smartphone research, collaborators have developed apps for researching asthma, breast cancer, cardiovascular disease, type 2 diabetes, and Parkinson disease. These research apps enhance widespread participation by removing geographical barriers to participation, provide novel ways to motivate healthy behaviors, facilitate high-frequency assessments, and enable more objective data collection. Although the studies have great potential, they also have notable limitations. These include selection bias, identity uncertainty, design limitations, retention, and privacy. As smartphone technology becomes increasingly available, researchers must recognize these factors to ensure that medical research is conducted appropriately. Despite these limitations, the future of smartphones in health research is bright. Their convenience grants unprecedented geographic freedom to researchers and participants alike and transforms the way clinical research can be conducted.
Clinician–Educators as Dual Professionals: A Contemporary Reappraisal
Authors: Stoddard Hugh A. , Brownfield Erica D.
Published: April 2016

Physicians who teach face unique responsibilities and expectations because they must educate learners while simultaneously caring for patients. Recently this has become even more difficult as the environment for clinician–educators has been undermined by public antipathy toward both the education profession and the medicine profession.

Erosion of public confidence in both professions is evidenced by three trends. First, the democratizing nature of the Internet and the availability of technical knowledge to laypeople have encroached on the domain of professional knowledge. Second, the responsibility of a professional to make decisions has been undercut by legal interpretations regarding how physicians are paid for patient care and how teachers are evaluated on performance. And finally, altruistic motivations in both professions have been called into question by external forces promoting “accountability” rather than trusting professionals to act for the best interest of their patients or students.

In this climate of increasing accountability and decreasing trust for professionals, clinician–educators can best serve patients and learners through transdisciplinary collaboration with professional educators. Clinician–educators should rely on professional educators for judgment and specialized knowledge in the field of education rather than embodying both professions by themselves. Health care practice has become more team oriented; health care education should do likewise to counteract the social and political trends eroding public confidence in medicine and education. Relying on collaboration with education professionals constitutes a substantial change to how clinician–educators define themselves, but it holds the best promise for medical training in the current social milieu.
Comparison of the yield from two faecal immunochemical tests at identical cutoff concentrations – a randomized trial in Latvia
Authors: Santare Daiga , Kojalo Ilona , Liepniece-Karele Inta , Kikuste Ilze , Tolmanis Ivars , Polaka Inese , Vikmanis Uldis , Boka Viesturs , Leja Marcis
Published: April 2016

Objective

We have compared the performance of two faecal immunochemical tests (FIT) in an average-risk population.

Materials and methods

Altogether, 10 000 individuals aged 50–74 were selected randomly from the population of Latvia in 2011 and assigned randomly either to OC-Sensor or to FOB Gold single-time testing. Positivity of the test, frequency of colonic lesions, number needed to screen (NNscreen) and scope for the detection of an advanced neoplasm (cancer and advanced adenoma) were compared between the tests using the same cutoff concentrations in µg/g faeces. Confidence intervals (CIs) at 95% were calculated.

Results

Positivity with the cutoff set at 10 µg/g faeces was 12.8% (95% CI: 11.4–14.2) for FOB Gold and 8.3% (95% CI: 7.2–9.4) for OC-Sensor (P<0.001). Positivity was higher in men and the older age groups. Colonoscopy compliance was 55.5%. There was no significant difference between the two tests at comparable cutoff concentrations in µg/g, colonoscopy attendance rate or colonoscopy results. For advanced neoplasm detection, there was no significant difference in number needed to scope and NNscreen at a cutoff of 10 µg/g faeces; however, lower NNscreen was required to detect advanced neoplasms with the FOB Gold test at increased cutoff concentrations.

Conclusion

Different quantitative FIT systems may report different positivity rate at identical cutoff concentrations, which has to be considered when implementing the use of FIT in national screening programmes.
Psychological Strains and Suicidal Intent
Authors: Sun Long , Zhang Jie
Published: April 2016

Psychological strains are hypothesized to precede a suicidal intent that may lead to suicide, where psychological strains can be considered a function of social structure embedded with negative life events. This study aimed to test the potential relationship between psychological strains and suicidal intent in Chinese rural suicide attempters. Data regarding medically serious suicide attempters (N = 791) were gathered from county-level emergency rooms in randomly selected counties in rural China (15–54 years of age). Face-to-face interview data were obtained with semistructured instruments. Results showed that the strain variables interacted with gender in predicting degree of suicide intent in Chinese rural suicide attempters. Specifically, aspiration strain and coping strain were associated with suicide intent in Chinese male suicide attempters, whereas value strain was associated with suicide intent in Chinese female suicide attempters. This study supported the strain hypothesis in Chinese rural suicide attempters.
Development of a Prediction Model of Early Acute Kidney Injury in Critically Ill Children Using Electronic Health Record Data
Authors: Sanchez-Pinto L. Nelson , Khemani Robinder G.
Published: April 2016

Objective:

Acute kidney injury is independently associated with poor outcomes in critically ill children. However, the main biomarker of acute kidney injury, serum creatinine, is a late marker of injury and can cause a delay in diagnosis. Our goal was to develop and validate a data-driven multivariable clinical prediction model of acute kidney injury in a general PICU using electronic health record data.

Design:

Derivation and validation of a prediction model using retrospective data.

Patients:

All patients 1 month to 21 years old admitted between May 2003 and March 2015 without acute kidney injury at admission and alive and in the ICU for at least 24 hours.

Setting:

A multidisciplinary, tertiary PICU.

Intervention:

The primary outcome was early acute kidney injury, which was defined as new acute kidney injury developed in the ICU within 72 hours of admission. Multivariable logistic regression was performed to derive the Pediatric Early AKI Risk Score using electronic health record data from the first 12 hours of ICU stay.

Measurements and Main Results:

A total of 9,396 patients were included in the analysis, of whom 4% had early acute kidney injury, and these had significantly higher mortality than those without early acute kidney injury (26% vs 3.3%; p < 0.001). Thirty-three candidate variables were tested. The final model had seven predictors and had good discrimination (area under the curve 0.84) and appropriate calibration. The model was validated in two validation sets and maintained good discrimination (area under the curves, 0.81 and 0.86).

Conclusion:

We developed and validated the Pediatric Early AKI Risk Score, a data-driven acute kidney injury clinical prediction model that has good discrimination and calibration in a general PICU population using only electronic health record data that is objective, available in real time during the first 12 hours of ICU care and generalizable across PICUs. This prediction model was designed to be implemented in the form of an automated clinical decision support system and could be used to guide preventive, therapeutic, and research strategies.
Lithium or Valproate Adjunctive Therapy to Second-generation Antipsychotics and Metabolic Variables in Patients With Schizophrenia or Schizoaffective Disorder
Authors: VINCENZI BRENDA , GREENE CLAIRE M. , ULLOA MELISSA , PARNAROUSKIS LINDSEY , JACKSON JOHN W. , HENDERSON DAVID C.
Published: April 2016

Objective:

People with schizophrenia are at greater risk for cardiovascular disease and their overall mortality rate is elevated compared to the general population. The metabolic side effects of antipsychotic medications have been widely studied; however, the effect of adding conventional mood stabilizers, such as lithium and valproate, to antipsychotic medication has not been assessed in terms of metabolic risk. The primary purpose of this secondary analysis was to examine whether treatment with lithium or valproate in addition to a second-generation antipsychotic is associated with poorer metabolic outcomes than treatment with a second-generation antipsychotic without lithium or depakote.

Methods:

Baseline data from 3 studies, which included measurement of body mass index, waist circumference, fasting glucose, insulin, homeostatic model assessment of insulin resistance, insulin sensitivity index, glucose utilization, and acute insulin response to glucose, were included in the analysis.

Results:

No differences were found between those taking lithium or valproate and those who were not in terms of fasting glucose, fasting insulin, and homeostatic model assessment of insulin resistance. Insulin sensitivity was lower among participants taking lithium or valproate. Participants taking lithium or valproate had a higher body mass index than those not taking conventional mood stabilizers, although the difference did not reach statistical significance.

Conclusions:

These cross-sectional findings suggest it may be beneficial to monitor insulin sensitivity and body mass index in patients taking lithium or valproate in combination with a second-generation antipsychotic.
Commentary on 2 Cases of Takotsubo Cardiomyopathy Involving Psychotropic Medication
Authors: VERDUIN MARCIA L.
Published: April 2016

Takotsubo cardiomyopathy, also known as Takotsubo syndrome (TTS), is a cardiac syndrome first described in Japan in 1990 that typically follows an acute physical or psychiatric stressor, hence its association with the terms “broken heart syndrome” and stress cardiomyopathy. Although it is relatively rare, occurring in only 0.02% of the general population and roughly 2% of patients with acute coronary syndrome, neurological or psychiatric disorders are present in over 50% of affected individuals. One of the major hypotheses regarding the pathophysiology of TTS involves a catecholamine surge, from stress directly, or in some cases from psychiatric medication used to relieve distress. Given the association of TTS with acute stress and psychiatric illness, psychiatrists may be involved in the care of patients with TTS either at the initial presentation of the condition or following recovery. The case reports presented in this issue exemplify these 2 scenarios: one case involves the development of TTS during treatment with atomoxetine, and the other case involves treatment of depression in a patient after recovery from TTS, as well as a TTS recurrence during treatment with fluoxetine.
Age at the Time of Surgery and Maintenance of Head Size in Nonsyndromic Sagittal Craniosynostosis
Authors: Bergquist Curtis S. , Nauta Allison C. , Selden Nathan R. , Kuang Anna A.
Published: April 2016

Background:

Repair of nonsyndromic sagittal craniosynostosis should durably improve intracranial volume and cranial index. The optimal timing of surgery is not known. The authors previously reported reoperation in patients aged younger than 6 months at primary repair.

Methods:

Patients undergoing primary reconstruction for sagittal craniosynostosis before age 1 year between 2005 and 2013 at Oregon Health & Science University underwent retrospective computed tomographic determination of cranial index and intracranial volume preoperatively and 2 years postoperatively and head circumference measurements until age 6 years.

Results:

Fifty-six patients undergoing operation before their first birthday were studied in two groups: those younger than 6 months [34 (61 percent)] and those aged 6 months or older at the time of operation. Head circumference percentile increased immediately after surgery but decreased at 1 and 2 years after surgery, significantly more so in patients younger than 6 months (p < 0.015 at 1 year; p < 0.011 at 2-year follow-up). Mean 2-year postoperative cranial index was significantly increased in both groups (p < 0.001), which did not differ preoperatively (younger than 6 months, 76.5; 6 months or older, 78.0) or 2 years postoperatively (younger than 6 months, 88.4; 6 months or older, 87.1; p = not significant). Intracranial volume increased in all patients from before surgery to 2 years postoperatively and was higher in the patients aged 6 months or older (p < 0.001).

Conclusion:

Cranial reconstruction for nonsyndromic sagittal craniosynostosis improved cranial index equally in all patients but increased head circumference and intracranial volume significantly more in patients who underwent surgical reconstruction at age 6 months or older.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
Dual-Pedicle Flap for Unilateral Autologous Breast Reconstruction Revisited: Evolution and Optimization of Flap Design over 15 Years
Authors: Chang Edward I. , Kronowitz Steven J.
Published: April 2016

Background:

In thin patients or when a significant amount of skin is needed, use of the entire abdomen to reconstruct a single breast may be necessary. In this article, the authors present their 15-year experience in dual-pedicle flap evolution and optimization of flap design.

Methods:

A retrospective review was conducted of all bipedicle flaps performed from 2000 to 2015.

Results:

Overall, 57 patients (mean age, 49.2 years; mean body mass index, 26.2 kg/m2) underwent dual-pedicle flap reconstruction of a unilateral mastectomy defect. Thirteen patients had a history of smoking, 30 patients had previously undergone irradiation, and 21 patients underwent immediate reconstruction. Eleven bipedicle flaps were performed with a pedicle transverse rectus abdominis musculocutaneous (TRAM) flap coupled to a free TRAM (n = 4), muscle-sparing TRAM (n = 4), or deep inferior epigastric artery perforator (DIEP) (n = 3) flap, and all were performed from 2000 to 2007. The thoracodorsal vessels (n = 8) were used more frequently earlier in the study period with the internal mammary vessels, whereas the antegrade/retrograde internal mammary vessels were used in the remaining patients, except for three patients in whom the internal mammary vessels and an internal mammary vessel perforator were used. Over the study period, there was an increase in the use of DIEP and superficial inferior epigastric artery flaps and the internal mammary vessels as recipients. Complications included delayed wound healing (n = 6), abdominal bulge (n = 2), cellulitis (n = 4), seroma (n = 3), and fat necrosis (n = 4). There was one partial flap loss where the superficial inferior epigastric artery portion of the dual-pedicle flap was lost.

Conclusions:

Dual-pedicle free flaps can be performed safely and reliably. Use of DIEP flaps maximizes pedicle length, and the internal mammary vessels can be used reliably in an antegrade and retrograde fashion to perfuse both components of the dual-pedicle flap.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, IV.
Inequalities in Specialist Hand Surgeon Distribution across the United States
Authors: Rios-Diaz Arturo J. , Metcalfe David , Singh Mansher , Zogg Cheryl K. , Olufajo Olubode A. , Ramos Margarita S. , Caterson Edward J. , Talbot Simon G.
Published: April 2016

Background:

Unequal access to hospital specialists for emergency care is an issue in the United States. The authors sought to describe the geographic distribution of specialist hand surgeons and associated factors in the United States.

Methods:

Geographic distributions of surgeons holding a Subspecialty Certificate in Surgery of the Hand and hand surgery fellowship positions were identified from the American Board of Medical Specialties Database and the literature (2013), respectively. State-level population and per capita income were ascertained using U.S. Census data. Variations in hand trauma admissions were determined using Healthcare Cost and Utilization Project national/state inpatient databases. Risk-adjusted generalized linear models were used to assess independent association between hand surgeon density and hand trauma admission density, fellowship position density, and per capita income.

Results:

Among 2019 specialist hand surgeons identified, 72.1 percent were orthopedic surgeons, 18.3 percent were plastic surgeons, and 9.6 percent were general surgeons. There were 157 hand surgery fellowship positions nationwide. There were 149,295 annual hand trauma admissions. The national density of specialist hand surgeons and density of trauma admission were 0.6 and 47.6, respectively. The density of specialist hand surgeons varied significantly between states. State-level variations in density of surgeons were independent and significantly associated with median per capita income (p < 0.001) and with density of fellowships (p = 0.014).

Conclusions:

Specialist hand surgeons are distributed unevenly across the United States. State-level analyses suggest that states with lower per capita incomes may be particularly underserved, which may contribute to regional disparities in access to emergency hand trauma care.
Biotic and abiotic variables influencing plant litter breakdown in streams: a global study
Authors: Boyero Luz , Pearson Richard G. , Hui Cang , Gessner Mark O. , Pérez Javier , Alexandrou Markos A. , Graça Manuel A. S. , Cardinale Bradley J. , Albariño Ricardo J. , Arunachalam Muthukumarasamy , Barmuta Leon A. , Boulton Andrew J. , Bruder Andreas , Callisto Marcos , Chauvet Eric , Death Russell G. , Dudgeon David , Encalada Andrea C. , Ferreira Verónica , Figueroa Ricardo , Flecker Alexander S. , Gonçalves José F. , Helson Julie , Iwata Tomoya , Jinggut Tajang , Mathooko Jude , Mathuriau Catherine , M'Erimba Charles , Moretti Marcelo S. , Pringle Catherine M. , Ramírez Alonso , Ratnarajah Lavenia , Rincon José , Yule Catherine M.
Published: April 2016

Plant litter breakdown is a key ecological process in terrestrial and freshwater ecosystems. Streams and rivers, in particular, contribute substantially to global carbon fluxes. However, there is little information available on the relative roles of different drivers of plant litter breakdown in fresh waters, particularly at large scales. We present a global-scale study of litter breakdown in streams to compare the roles of biotic, climatic and other environmental factors on breakdown rates. We conducted an experiment in 24 streams encompassing latitudes from 47.8° N to 42.8° S, using litter mixtures of local species differing in quality and phylogenetic diversity (PD), and alder (Alnus glutinosa) to control for variation in litter traits. Our models revealed that breakdown of alder was driven by climate, with some influence of pH, whereas variation in breakdown of litter mixtures was explained mainly by litter quality and PD. Effects of litter quality and PD and stream pH were more positive at higher temperatures, indicating that different mechanisms may operate at different latitudes. These results reflect global variability caused by multiple factors, but unexplained variance points to the need for expanded global-scale comparisons.
Coevolution of venom function and venom resistance in a rattlesnake predator and its squirrel prey
Authors: Holding Matthew L. , Biardi James E. , Gibbs H. Lisle
Published: April 2016

Measuring local adaptation can provide insights into how coevolution occurs between predators and prey. Specifically, theory predicts that local adaptation in functionally matched traits of predators and prey will not be detected when coevolution is governed by escalating arms races, whereas it will be present when coevolution occurs through an alternate mechanism of phenotype matching. Here, we analyse local adaptation in venom activity and prey resistance across 12 populations of Northern Pacific rattlesnakes and California ground squirrels, an interaction that has often been described as an arms race. Assays of venom function and squirrel resistance show substantial geographical variation (influenced by site elevation) in both venom metalloproteinase activity and resistance factor effectiveness. We demonstrate local adaptation in the effectiveness of rattlesnake venom to overcoming present squirrel resistance, suggesting that phenotype matching plays a role in the coevolution of these molecular traits. Further, the predator was the locally adapted antagonist in this interaction, arguing that rattlesnakes are evolutionarily ahead of their squirrel prey. Phenotype matching needs to be considered as an important mechanism influencing coevolution between venomous animals and resistant prey.
Consecutive cohort effects driven by density-dependence and climate influence early-life survival in a long-lived bird
Authors: Payo-Payo A. , Genovart M. , Bertolero A. , Pradel R. , Oro D.
Published: April 2016

Conditions during early life, including maternal cohort effects, can influence the future fitness of individuals. This may be particularly true for long-distance migrating birds, because, apart from conditions experienced by cohorts during rearing, conditions during early life in regions far from breeding grounds may also influence their population dynamics. Very little is known about the fitness consequences of those conditions experienced by juveniles after independence, especially in wild populations and for long-lived birds. We used multi-event capture–recapture–recovery models and a unique 26-year dataset for the Audouin's gull (
Larus audouinii
) to assess for the first time whether survival was influenced by early conditions, both during the rearing period (i.e. a maternal cohort effect potentially affected by density dependence) and the first winter (i.e. a cohort effect driven by climate when birds disperse to wintering grounds). Our results show that juvenile survival was highly sensitive to early-life conditions and that survival decreased with stronger density dependence and harsh climate. The two consecutive cohort effects were of similar magnitude and they may represent a selection filter. Thus, early-life conditions had a strong impact on survival, and neglecting this complexity may hinder our understanding on how populations of long-lived animals fluctuate and respond to perturbations.
Temporal and spatial expression patterns of biomineralization proteins during early development in the stony coral
Pocillopora damicornis
Authors: Mass Tali , Putnam Hollie M. , Drake Jeana L. , Zelzion Ehud , Gates Ruth D. , Bhattacharya Debashish , Falkowski Paul G.
Published: April 2016

Reef-building corals begin as non-calcifying larvae that, upon settling, rapidly begin to accrete skeleton and a protein-rich skeletal organic matrix that attach them to the reef. Here, we characterized the temporal and spatial expression pattern of a suite of biomineralization genes during three stages of larval development in the reef-building coral
Pocillopora damicornis
: stage I, newly released; stage II, oral-aborally compressed and stage III, settled and calcifying spat. Transcriptome analysis revealed 3882 differentially expressed genes that clustered into four distinctly different patterns of expression change across the three developmental stages. Immunolocalization analysis further reveals the spatial arrangement of coral acid-rich proteins (CARPs) in the overall architecture of the emerging skeleton. These results provide the first analysis of the timing of the biomineralization ‘toolkit’ in the early life history of a stony coral.
Shear test as calibration experiment for DEM simulations: a sensitivity study
Authors: Keppler Istvan , Safranyik Ferenc , Oldal Istvan
Published: April 2016

Purpose

The effect of micromechanical parameters on the macromechanical behaviour of granular materials is analysed by using discrete element based model of the standard shear test.

Design/methodology/approach

Discrete element method based standard shear test simulations.

Findings

The approximate mathematical functions related to the effects of DEM micromechanical parameters density, Young-modulus, Poisson number, frictional angle, bond normal cohesion, bond tangential cohesion, rolling friction and particle shape on the macromechanical parameters of shear failure line (internal friction and cohesion) are determined by modelling large number of standard shear tests.

Originality/value

By knowing these effects of micromechanical parameters to the macromechanical behaviour of the simulated particle assembly, the calibration of discrete element models can be significantly accelerated.
Derivation of the material models for ultra-high molecular-weight polyethylene fiber-reinforced armor-grade composites with different architectures
Authors: Grujicic Mica , Snipes Jennifer , Ramaswami S. , Avuthu Vasudeva , Yen Chian-Fong , Cheeseman Bryan
Published: April 2016

Purpose

To overcome the problem of inferior through-the-thickness mechanical properties displayed by armor-grade composites based on 2-D reinforcement architectures, armor-grade composites based on 3D fiber-reinforcement architectures have recently been investigated experimentally.

Design/methodology/approach

The subject of the present work is armor-grade composite materials reinforced using ultra-high-molecular-weight polyethylene fibers and having four (two 2D and two 3D) prototypical architectures, as well as the derivation of the corresponding material models. The effect of the reinforcement architecture is accounted for by constructing the appropriate unit cells (within which the constituent materials and their morphologies are represented explicitly) and subjecting them to a series of virtual mechanical tests. The results obtained are used within a post-processing analysis to derive and parameterize the corresponding homogenized-material models. One of these models (specifically, the one for 0°/90° cross-collimated fiber architecture) was directly validated by comparing its predictions with the experimental counterparts. The other models are validated by examining their physical soundness and details of their predictions. Lastly, the models are integrated as user-material subroutines, and linked with a commercial finite-element package, in order to carry out a transient non-linear dynamics analysis of ballistic transverse impact of armor-grade composite-material panels with different reinforcement architectures.

Findings

It is found that the reinforcement architecture plays a critical role in the overall ballistic limit of the armor panel, as well as in its structural and damage/failure response.

Originality/value

To the authors’ knowledge, the present work is the first reported attempt to assess, computationally, the utility and effectiveness of 3D fiber-reinforcement architectures for ballistic impact applications.
Seizing opportunities for change at the operational level
Authors: Restrepo Diana , Charron-Latour Julie , Pourmonet Hugo , Bassetto Samuel
Published: April 2016

Purpose

This article presents a method for handling everyday opportunities for improvement, led by floor staff in health care institutions. More than 400,000 incidents and accidents were recorded in Quebec health care institutions in 2013. The burden of treatment falls on hospital floor staff. The purpose is to raise the visibility of this problem and support staff better in their efforts to handle opportunities for improvement.

Design/methodology/approach

Based on issues identified in the literature, which have been found to exist in various organizations, the method involved reviewing practices in the field, proposing a solution, and testing it to assess its relevance and limitations. The method was tested in partnership with the Centre Hospitalier de l’Université de Montréal, in the internal medicine unit at Hôtel-Dieu campus. The test lasted three months. Indicators from this test have been compared to results in the literature.

Findings

The proposed method presents a 68% increase in ideas generated per person and per week compared to the reference study. The mean time for closing actions was about 41% better (lower) than in the reference case.

Research limitations/implications

The test lasted 15 weeks; a longer test is needed to collect more data.

Practical implications

The first practical implication of this study was the creation of a method allowing employees to seize opportunities for improvement in their daily work. The application of this method revealed (1) the operational nature of the proposal (empowerment of the work team); (2) the operationalization of continuous improvement (71% of ideas were finalized while the initiative was monitored); (3) the smooth operation of the mechanism for facilitating continuous improvement (organization of weekly meetings and team participation in these meetings in 90% of cases); and (4) a shared feeling that intra- and inter-team communication had been strengthened.

Originality/value

The main value of this paper is that it proposes a simple problem-solving process that gives employees an opportunity to improve their daily work. The originality of this paper resides in comparing results to a standard case and observing an improvement. This paper proposes a new problem-solving structure and tests it scientifically.