bluuebunny/crossref_metadata_2025_split huggingface dataset:
The laser diode structure
Authors: Blood Peter 
Published: November 2015

Abstract
A laser diode structure calls for materials of different band gap to provide optical and electrical confinement and these should have a similar lattice parameter to the substrate on which they are grown. This is achieved using direct-gap compound semiconductors and their alloys in which the band gap and lattice parameter change with the composition. Typical III–V alloy systems used for laser structures are described. In some cases modest amounts of strain can give improvements in laser performance. Semiconductor alloy materials of different band gap are combined to form heterostructures, which are characterised by the band offsets at the interface between them. These materials may be the same carrier type throughout or incorporate a p–n junction to inject carriers to achieve population inversion. Construction of the energy band diagrams of these structures and of quantum wells is described.
Temperature dependence of threshold current
Authors: Blood Peter 
Published: November 2015

Abstract
The variation of the threshold current density with temperature is an important characteristic of a diode laser and considerable effort is devoted to designing devices that have a temperature-insensitive threshold current to avoid the expense, and power consumption, of device cooling. This chapter sets out the physics that determines this dependence, together with some illustrative examples. Relevant processes include Auger recombination and carrier leakage out of the confined region, as well as barrier recombination and current flow through the cladding layers by drift and diffusion. In quantum dot lasers the wetting layer has significant influence on the temperature dependence. In a VCSEL the temperature dependence of threshold is determined by the need to meet the threshold condition at the cavity resonance rather than the gain peak. The conditions surrounding the use of the characteristic temperature T0 as a measure of temperature sensitivity are described.
Body Mass Index, Weight Gain, and Hypertensive Disorders in
Pregnancy
Authors: Masho Saba W. , Urban Peter , Cha Susan , Ramus Ronald 
Published: November 2015

Abstract

BACKGROUND
This study examines the interrelationship between gestational weight gain, pre-pregnancy body mass index (BMI), race/ethnicity, and their association with hypertensive disorders during pregnancy (HDP).

METHODS
Data from the 2004–2011 national Pregnancy Risk Assessment Monitoring System (PRAMS) were analyzed. Women with singleton live births were included in the analysis ( N = 270,131). Gestational weight gain was categorized reflecting the Institute of Medicine (IOM) weight gain recommendation (no gain/weight loss; ≤11, 12–14; 15–25; 26–35; ≥36 pounds). Pre-pregnancy BMI (underweight; normal; overweight; obese) and race/ethnicity (non-Hispanic (NH) White, NH-Black, Hispanic, and NH-other) were examined. Hypertensive disorders during pregnancy were dichotomized (HDP; no HDP). Data were stratified by BMI and race/ethnicity, and multiple logistic regression analysis was conducted to generate odds ratios and 95% confidence intervals (CIs).

RESULTS
Compared to normal and overweight women who gained the IOM recommended weight, higher odds of HDP was observed in those who gained ≥36 pounds regardless of their race/ethnicity. Among obese NH-White (odds ratio (OR) = 1.29, 95% CI = 1.11, 1.50) and Hispanic women (OR = 1.64, 95% CI = 1.05, 2.54), the odds of HDP was higher among those who gained 25–35 pounds and those who gained ≥36 pounds (OR = 1.59, 95% CI = 1.37, 1.85) and (OR = 2.20, 95% CI = 1.41, 3.44), respectively. However, for NH-Black obese women, higher odds of HDP was observed among those who gained ≥36 pounds (OR = 1.34, 95% CI = 1.04, 1.73).

CONCLUSIONS
Although there are some ethnic/racial variations, pregnant women who exceeded gestational weight gain recommendations are at increased risk of HDP. Health care providers should consider the interrelationship between pre-pregnancy gestational weight gain (GWG) and BMI when counseling patients regarding HDP.
Rising drug allergy alert overrides in electronic health records: an observational retrospective study of a decade of experience
Authors: Topaz Maxim , Seger Diane L , Slight Sarah P , Goss Foster , Lai Kenneth , Wickner Paige G , Blumenthal Kimberly , Dhopeshwarkar Neil , Chang Frank , Bates David W , Zhou Li 
Published: November 2015

Objective There have been growing concerns about the impact of drug allergy alerts on patient safety and provider alert fatigue. The authors aimed to explore the common drug allergy alerts over the last 10 years and the reasons why providers tend to override these alerts.Design: Retrospective observational cross-sectional study (2004–2013).Materials and Methods Drug allergy alert data (n = 611,192) were collected from two large academic hospitals in Boston, MA (USA).Results Overall, the authors found an increase in the rate of drug allergy alert overrides, from 83.3% in 2004 to 87.6% in 2013 (P &lt; .001). Alarmingly, alerts for immune mediated and life threatening reactions with definite allergen and prescribed medication matches were overridden 72.8% and 74.1% of the time, respectively. However, providers were less likely to override these alerts compared to possible (cross-sensitivity) or probable (allergen group) matches (P &lt; .001). The most common drug allergy alerts were triggered by allergies to narcotics (48%) and other analgesics (6%), antibiotics (10%), and statins (2%). Only slightly more than one-third of the reactions (34.2%) were potentially immune mediated. Finally, more than half of the overrides reasons pointed to irrelevant alerts (i.e., patient has tolerated the medication before, 50.9%) and providers were significantly more likely to override repeated alerts (89.7%) rather than first time alerts (77.4%, P &lt; .001).Discussion and Conclusions These findings underline the urgent need for more efforts to provide more accurate and relevant drug allergy alerts to help reduce alert override rates and improve alert fatigue.
Risks and benefits of speech recognition for clinical documentation: a systematic review
Authors: Hodgson Tobias , Coiera Enrico 
Published: November 2015

AbstractObjective To review literature assessing the impact of speech recognition (SR) on clinical documentation.Methods Studies published prior to December 2014 reporting clinical documentation using SR were identified by searching Scopus, Compendex and Inspect, PubMed, and Google Scholar. Outcome variables analyzed included dictation and editing time, document turnaround time (TAT), SR accuracy, error rates per document, and economic benefit. Twenty-three articles met inclusion criteria from a pool of 441.Results Most studies compared SR to dictation and transcription (DT) in radiology, and heterogeneity across studies was high. Document editing time increased using SR compared to DT in four of six studies (+1876.47% to –16.50%). Dictation time similarly increased in three of five studies (+91.60% to –25.00%). TAT consistently improved using SR compared to DT (16.41% to 82.34%); across all studies the improvement was 0.90% per year. SR accuracy was reported in ten studies (88.90% to 96.00%) and appears to improve 0.03% per year as the technology matured. Mean number of errors per report increased using SR (0.05 to 6.66) compared to DT (0.02 to 0.40). Economic benefits were poorly reported.Conclusions SR is steadily maturing and offers some advantages for clinical documentation. However, evidence supporting the use of SR is weak, and further investigation is required to assess the impact of SR on documentation error types, rates, and clinical outcomes.
Patient-specific Immune States before Surgery Are Strong Correlates of Surgical Recovery
Authors: Fragiadakis Gabriela K. , Gaudillière Brice , Ganio Edward A. , Aghaeepour Nima , Tingle Martha , Nolan Garry P. , Angst Martin S. 
Published: November 2015

AbstractAbstract
In an analysis of the same group of orthopedic surgery patients from the postoperative sample study, preoperative immune state as assessed by mass cytometry of blood samples was predictive of recovery across several domains, with toll-like receptor 4 signaling in cluster of differentiation 14+ monocytes accounted for 50% of observed variance.
Supplemental Digital Content is available in the text.

Background
Recovery after surgery is highly variable. Risk-stratifying patients based on their predicted recovery profile will afford individualized perioperative management strategies. Recently, application of mass cytometry in patients undergoing hip arthroplasty revealed strong immune correlates of surgical recovery in blood samples collected shortly after surgery. However, the ability to interrogate a patient’s immune state before surgery and predict recovery is highly desirable in perioperative medicine.

Methods
To evaluate a patient’s presurgical immune state, cell-type–specific intracellular signaling responses to ex vivo ligands (lipopolysaccharide, interleukin [IL]-6, IL-10, and IL-2/granulocyte macrophage colony-stimulating factor) were quantified by mass cytometry in presurgical blood samples. Selected ligands modulate signaling processes perturbed by surgery. Twenty-three cell surface and 11 intracellular markers were used for the phenotypic and functional characterization of major immune cell subsets. Evoked immune responses were regressed against patient-centered outcomes, contributing to protracted recovery including functional impairment, postoperative pain, and fatigue.

Results
Evoked signaling responses varied significantly and defined patient-specific presurgical immune states. Eighteen signaling responses correlated significantly with surgical recovery parameters (|R| = 0.37 to 0.70; false discovery rate < 0.01). Signaling responses downstream of the toll-like receptor 4 in cluster of differentiation (CD) 14+ monocytes were particularly strong correlates, accounting for 50% of observed variance. Immune correlates identified in presurgical blood samples mirrored correlates identified in postsurgical blood samples.

Conclusions
Convergent findings in pre- and postsurgical analyses provide validation of reported immune correlates and suggest a critical role of the toll-like receptor 4 signaling pathway in monocytes for the clinical recovery process. The comprehensive assessment of patients’ preoperative immune state is promising for predicting important recovery parameters and may lead to clinical tests using standard flow cytometry.
Cerebrospinal Fluid Biomarker for Alzheimer Disease Predicts Postoperative Cognitive Dysfunction
Authors: Evered Lisbeth , Silbert Brendan , Scott David A. , Ames David , Maruff Paul , Blennow Kaj 
Published: November 2015

AbstractAbstract
There was an association between low preoperative levels of amyloid β in the cerebrospinal fluid and postoperative cognitive dysfunction (POCD) at 3 months; POCD was not observed at 12 months. Patients with Alzheimer’s disease neuropathology, identified by low cerebrospinal fluid levels of amyloid β, may be at an increased risk of POCD even in the absence of clinically detectable symptoms.

Background
Postoperative cognitive dysfunction (POCD) affects 16 to 21% of the elderly 3 months after anesthesia and surgery and is associated with adverse outcomes. The exact cause of POCD remains unknown. The authors hypothesized that elderly individuals with Alzheimer disease (AD) neuropathology, identified by cerebrospinal fluid (CSF) analysis, would have increased the risk for POCD.

Methods
CSF samples were collected from 59 patients 60 yr or older who received combined spinal and general anesthesia for elective total hip replacement. Patients underwent neuropsychological testing preoperatively and at 7 days, 3 months, and 12 months postoperatively. POCD at 3 months and cognitive decline at 12 months were calculated by using the reliable change index. CSF amyloid β1–
42 (Aβ1–
42), total-tau, phosphorylated-tau, and neurofilament light were assayed with enzyme-linked immunosorbent assay methods.

Results
POCD was identified in 5 of 57 patients (8.8%) at 3 months. For Aβ1–
42, 11 patients were below the cut-point for AD neuropathology of whom 3 were classified with POCD (27.3%; 95% CI, 6.0 to 61%), whereas of the 46 patients above the cut-point, 2 were classified with POCD (4.3%; 95% CI, 0.5 to 14.8%) (P = 0.01). There was no significant difference in the incidence of POCD in relation to the cut-points for any of the other analytes.

Conclusions
Low CSF Aβ1–
42 may be a significant predictor of POCD at 3 months. This indicates that patients with AD neuropathology even in the absence of clinically detectable AD symptoms may be susceptible to POCD.
Intraoperative Monitoring of Diaphragm Neural Pathways During Cervical Surgery by Electrical Stimulation and Recordings of Ventilator Waveforms: Physiological Bases and Pilot Study
Authors: Georgoulis George , Papagrigoriou Eirini , Pardey Bracho Gilda F. , Mertens Patrick , Sindou Marc 
Published: November 2015

Background:
Surgery on the cervical spine entails the risk of damaging the neural structures responsible for diaphragmatic innervation, namely (C3)-C4-(C5) roots. In some “difficult” cases, anatomic identification of these structures may be hard to achieve. Therefore, monitoring of the diaphragm through the ventilation waveforms displayed on the anesthesia machine can be of practical help. According to literature review, very few publications have reported such monitoring.

Methods:
The present work aimed at investigating the feasibility and reliability of identifying cervical root(s) responsible for diaphragmatic innervation, by observing the changes on the recorded waveforms, indicating diaphragmatic responses to direct radicular electrical stimulation. In this study, the events not only on the capnography curve but also on pressure-time and flow-time waveforms were analyzed. Eight patients undergoing cervical Microsurgical DREZotomy (MDT) were enrolled in the study, as this surgical modality allows easy access to the C4 root, known to be prominent in diaphragmatic innervation. The technique did not require any harmful additional maneuver to the current anesthesia and surgical protocols.

Results:
Stimulation resulted in specific patterns of changes in the 3 waveforms in all 8 patients and proved “easy” to interpret, provided that close cooperation exists between the anesthesiologist and the surgeon.

Conclusion:
Intraoperative monitoring of the diaphragmatic responses to stimulation can be advocated in surgery at the cervical spine level, and also more widely in surgery in the supraclavicular region, when neural structures responsible for diaphragmatic function are at risk.
An Anatomic Study on Whether the Immature Patella is Centered on an Anteroposterior Radiograph
Authors: Kyriakedes James C. , Liu Raymond W. 
Published: November 2015

Background:
In the operating room, after first obtaining a proper lateral radiograph with the condyles superimposed, a 90-degree rotation of the intraoperative fluoroscopy unit does not always produce an anteroposterior (AP) image with the patella centered. The orthogonality of these 2 views has not been well determined in children.

Methods:
This study was comprised of a radiographic group (35 knees) and a cadaveric group (59 knees). Both cadaveric and clinical images were obtained by resting or positioning the femur with the posterior condyles overlapped, and then taking an orthogonal AP image. Centering of the patella was calculated and multiple regression analysis was performed to determine the relationship between patellar centering and age, sex, ethnicity, mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA), and contralateral centering.

Results:
Mean patellar centering, expressed as the lateral position of the patella with respect to the total condylar width, was 0.08±0.10 in the radiographic group and 0.06±0.03 in the cadaveric group. Positive (lateral) patellar centering in 1 knee had a statistically significant correlation with positive patellar centering in the contralateral knee in both the radiographs and the cadavers. In the radiographic group, there was a statistically significant correlation between femoral varus and valgus deformities and positive patellar centering. In the cadaveric group, there was a statistically significant correlation between tibial valgus and negative (medial) patellar centering.

Conclusion:
The patella in an immature knee is rarely perfectly centered on a true AP image, and is usually seated slightly laterally within the femoral condyles.

Clinical Relevance:
Obtaining a true AP intraoperative radiograph is critical to analyzing and correcting valgus and varus deformities, and in the proper placement of implants. When addressing knee deformity one should consider obtaining an AP view orthogonal either to a perfect lateral of the knee or orthogonal to the flexion axis of the knee, particularly when evaluating distal femoral deformity.
Self-Reported Sleep Disturbance Mediates the Relationship Between PTSD and Cognitive Outcome in Blast-Exposed OEF/OIF Veterans
Authors: Verfaellie Mieke , Lee Lewina O. , Lafleche Ginette , Spiro Avron 
Published: November 2015

Objectives:
To examine the contribution of sleep disturbance to cognitive performance following blast exposure.

Design:
Correlational research evaluating self-reported sleep disturbance as a mediator of the association between the primary blast-related comorbidities of mild traumatic brain injury (mTBI) and posttraumatic stress disorder and cognitive outcome.

Participants:
One hundred sixty Operation Enduring Freedom/Operation Iraqi Freedom Veterans with a history of blast exposure assigned to 1 of 3 groups (no TBI, mTBI without loss of consciousness, and mTBI with loss of consciousness).

Main Outcome Measures:
Neuropsychological measures and self-report of sleep disturbance.

Results:
Increased posttraumatic stress disorder symptomatology was associated with worse performance in multiple cognitive domains. This association was mediated in part by self-reported sleep disturbance. Traumatic brain injury with loss of consciousness was associated with lower manual dexterity, but this association was not mediated by sleep disturbance.

Conclusions:
Our results highlight the importance of sleep disturbance as a factor contributing to cognitive outcome in individuals with posttraumatic stress disorder symptoms. They point to the importance of considering sleep problems in the diagnosis and treatment of cognitive deficits in veterans with blast exposure.
Cognitive Intervention for Attention and Executive Function Impairments in Children With Traumatic Brain Injury: A Pilot Study
Authors: Treble-Barna Amery , Sohlberg McKay Moore , Harn Beth E. , Wade Shari L. 
Published: November 2015

Objective:
To test the effectiveness of the Attention Improvement and Management (AIM) program, a cognitive intervention for improving impairments in attention and executive functions (EFs) after pediatric traumatic brain injury (TBI).

Setting:
Tertiary care children's hospital.

Participants:
A total of 13 children with complicated mild-to-severe TBI (average of 5 years postinjury) and 11 healthy comparison children aged 9 to 15 years completed the study.

Design:
Open-label pilot study with a nontreated control group.

Main Measures:
Subtests from the Test of Everyday Attention-for Children (TEA-Ch) and the Delis–Kaplan Executive Function System (D-KEFS), the self- and parent-report from the Behavior Rating Inventory of Executive Function (BRIEF), and the Goal Attainment Scale (GAS).

Results:
Relative to the healthy comparison group, children with TBI demonstrated significant improvement postintervention on a neuropsychological measure of sustained attention, as well as on parent-reported EFs. The majority of families also reported expected or more-than-expected personalized goal attainment.

Conclusions:
The study provides preliminary evidence for the effectiveness of AIM in improving parent-reported EFs and personalized real-world goal attainment in children with TBI.
Vectorization techniques for efficient agent-based model simulations of tumor growth
Authors: Poleszczuk Jan , Enderling Heiko 
Published: November 2015

AbstractMulti-scale agent-based models are increasingly used to simulate tumor growth dynamics. Simulating such complex systems is often a great challenge despite large computational power of modern computers and, thus, implementation techniques are becoming as important as the models themselves. Here we show, using a simple agent-based model of tumor growth, how the computational time required for simulation can be decreased by using vectorization techniques. In numerical examples we observed up to 30-fold increases in computation performance when standard approaches were, at least in part, replaced with vectorized routines in MATLAB.
Integrating experimental data to calibrate quantitative cancer models
Authors: Enderling Heiko 
Published: November 2015

AbstractFor quantitative cancer models to be meaningful and interpretable the number of unknown parameters must be kept minimal. Experimental data can be utilized to calibrate model dynamics rates or rate constants. Proper integration of experimental data, however, depends on the chosen theoretical framework. Using live imaging of cell proliferation as an example, we show how to derive cell cycle distributions in agent-based models and averaged proliferation rates in differential equation models. We focus on a tumor hierarchy of cancer stem and progenitor non-stem cancer cells.