bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of millisecond flash lamp annealing on electrical and structural properties of ZnO:Al/Si structures
Authors: Lindberg P. F. , Lipp Bregolin F. , Wiesenhütter K. , Wiesenhütter U. , Riise H. N. , Vines L. , Prucnal S. , Skorupa W. , Svensson B. G. , Monakhov E. V.
Published: May 2016

The effect of millisecond flash lamp annealing (FLA) on aluminum doped ZnO (AZO) films and their interface with Si have been studied. The AZO films were deposited by magnetron sputtering on Si (100) substrates. The electrical and structural properties of the film and AZO/Si structures were characterized by current–voltage, capacitance–voltage, and deep level transient spectroscopy measurements, X-ray diffraction, and secondary ion mass spectrometry. The resistivity of the AZO film is reduced to a close to state-of-the-art value of 2 × 10−4 Ω cm after FLA for 3 ms with an average energy density of 29 J/cm2. In addition, most of the interfacial defects energy levels are simultaneously annealed out, except for one persisting shallow level, tentatively assigned to the vacancy-oxygen complex in Si, which was not affected by FLA. Subsequent to the FLA, the samples were treated in N2 or forming gas (FG) (N2/H2, 90/10%mole) ambient at 200–500 °C. The latter samples maintained the low resistivity achieved after the FLA, but not the former ones. The interfacial defect level persisting after the FLA is removed by the FG treatment, concurrently as another level emerges at ∼0.18 eV below the conduction band. The electrical data of the AZO films are discussed in term of point defects controlling the resistivity, and it is argued that the FLA promotes formation of electrically neutral clusters of Zink vacancies (VZn's) rather than passivating/compensating complexes between the Al donors and VZn's.
Effect of tetrahedral amorphous carbon coating on the resistivity and wear of single-walled carbon nanotube network
Authors: Iyer Ajai , Kaskela Antti , Novikov Serguei , Etula Jarkko , Liu Xuwen , Kauppinen Esko I. , Koskinen Jari
Published: May 2016

Single walled carbon nanotube networks (SWCNTNs) were coated by tetrahedral amorphous carbon (ta-C) to improve the mechanical wear properties of the composite film. The ta-C deposition was performed by using pulsed filtered cathodic vacuum arc method resulting in the generation of C+ ions in the energy range of 40–60 eV which coalesce to form a ta-C film. The primary disadvantage of this process is a significant increase in the electrical resistance of the SWCNTN post coating. The increase in the SWCNTN resistance is attributed primarily to the intrinsic stress of the ta-C coating which affects the inter-bundle junction resistance between the SWCNTN bundles. E-beam evaporated carbon was deposited on the SWCNTNs prior to the ta-C deposition in order to protect the SWCNTN from the intrinsic stress of the ta-C film. The causes of changes in electrical resistance and the effect of evaporated carbon thickness on the changes in electrical resistance and mechanical wear properties have been studied.
Correlation between valence state of tin and elastic modulus of Sn-doped Li2O–B2O3–SiO2 glasses
Authors: Masai Hirokazu , Matsumoto Syuji , Ueda Yuki , Koreeda Akitoshi
Published: May 2016

The correlation between the longitudinal elastic modulus c11 and tin valence state in Li2O–B2O3–SiO2 ternary glasses is investigated. Substitution of B2O3 for SiO2 increases the glass-transition temperature and c11 but decreases the melting temperature. 119Sn Mössbauer spectra show that the valence state of tin increased with increasing molten temperature, Tmolten, in air, and that it also affects the c11 value even though the 1.0 mol. % addition. The c11 values, whose error bars are governed by those of density, suggest that the addition of SnO2 increases c11 whereas SnO decreases. The relationship between Tmolten and the amount of Sn2+ suggests that the main factor affecting the tin valence state is oxygen, whose reactivity may correlate with the glass melt viscosity.
High-speed, high-voltage pulse generation using avalanche transistor
Authors: Yong-sheng Gou , Bai-yu Liu , Yong-lin Bai , Jun-jun Qin , Xiao-hong Bai , Bo Wang , Bing-li Zhu , Chuan-dong Sun
Published: May 2016

In this work, the conduction mechanism of avalanche transistors was demonstrated and the operation condition for generating high-speed pulse using avalanche transistors was illustrated. Based on the above analysis, a high-speed and high-voltage pulse (HHP) generating circuit using avalanche transistors was designed, and its working principle and process were studied. To improve the speed of the output pulse, an approach of reducing the rise time of the leading edge is proposed. Methods for selecting avalanche transistor and reducing the parasitic inductance and capacitance of printed circuit board (PCB) were demonstrated. With these instructions, a PCB with a tapered transmission line was carefully designed and manufactured. Output pulse with amplitude of 2 kV and rise time of about 200 ps was realized with this PCB mounted with avalanche transistors FMMT417, indicating the effectiveness of the HHP generating circuit design.
Active stabilization of ion trap radiofrequency potentials
Authors: Johnson K. G. , Wong-Campos J. D. , Restelli A. , Landsman K. A. , Neyenhuis B. , Mizrahi J. , Monroe C.
Published: May 2016

We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a radiofrequency (rf) Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic oscillation frequency to be better than 10 Hz or 10 ppm. This represents a suppression of ambient noise on the rf circuit by 34 dB. This technique could impact the sensitivity of ion trap mass spectrometry and the fidelity of quantum operations in ion trap quantum information applications.
A simple spectroscopic method to determine the degree of dissociation in hydrogen plasmas with wide-range spectrometer
Authors: Dang Jeong-Jeung , Chung Kyoung-Jae , Hwang Y. S.
Published: May 2016

A new and simple method for determining the degree of dissociation in hydrogen plasmas is presented. In this method, wide-range spectrum covering from an atomic H-γ line (434.05 nm) to molecular Fulcher-α band (600-640 nm) is measured simultaneously by a wide-range miniature spectrometer. Since the wide-range spectrum measured by the miniature spectrometer is too broadened to resolve respective lines in the Fulcher-α band, a synthetic spectrum method is applied to improve the accuracy in the Q-branch of Fulcher-α band intensity measurement. In order to reduce the influence from other transitions or anomalous P- and R-branch of Fulcher-α spectrum, the Fulcher-α spectra of which vibrational states are higher than 1 (υ ≥ 1) are synthesized using the rotational temperature obtained by the 0-0 Fulcher-α spectrum. The degree of dissociation is determined from the intensity ratio between H-γ line and the synthesized Fulcher-α band spectrum. A comparative study carried out in a volume-produced negative hydrogen ion source shows that the degree of dissociation determined by this method agrees well with the measured values using a spectrometer with high spectral resolution. The present method is expected to be useful to characterize the plasma sources with molecular species since it provides important parameters for understanding neutral particle behaviors.
A method for coincidence timing resolution enhancement
Authors: Ermis E. E. , Celiktas C. , Pilicer E.
Published: May 2016

A method including the coincidence time resolution improvement for a TOF/positron emission tomography system was suggested. The spectrometer for this aim was composed of two NaI(Tl) and two plastic scintillation detectors. Experimental results were supported by FLUKA Monte Carlo simulation program by constructing the detector setup in software medium. Present experimental results verified our previous results and conclusions obtained from the suggested method. It was concluded that better resolutions would help the improvement not only on the TOF gain but also on the spatial resolution, leading to better images and helping the Physician in his/her diagnosis and treatment.
Evaluation of molecular dynamics simulation methods for ionic liquid electric double layers
Authors: Haskins Justin B. , Lawson John W.
Published: May 2016

We investigate how systematically increasing the accuracy of various molecular dynamics modeling techniques influences the structure and capacitance of ionic liquid electric double layers (EDLs). The techniques probed concern long-range electrostatic interactions, electrode charging (constant charge versus constant potential conditions), and electrolyte polarizability. Our simulations are performed on a quasi-two-dimensional, or slab-like, model capacitor, which is composed of a polarizable ionic liquid electrolyte, [EMIM][BF4], interfaced between two graphite electrodes. To ensure an accurate representation of EDL differential capacitance, we derive new fluctuation formulas that resolve the differential capacitance as a function of electrode charge or electrode potential. The magnitude of differential capacitance shows sensitivity to different long-range electrostatic summation techniques, while the shape of differential capacitance is affected by charging technique and the polarizability of the electrolyte. For long-range summation techniques, errors in magnitude can be mitigated by employing two-dimensional or corrected three dimensional electrostatic summations, which led to electric fields that conform to those of a classical electrostatic parallel plate capacitor. With respect to charging, the changes in shape are a result of ions in the Stern layer (i.e., ions at the electrode surface) having a higher electrostatic affinity to constant potential electrodes than to constant charge electrodes. For electrolyte polarizability, shape changes originate from induced dipoles that soften the interaction of Stern layer ions with the electrode. The softening is traced to ion correlations vertical to the electrode surface that induce dipoles that oppose double layer formation. In general, our analysis indicates an accuracy dependent differential capacitance profile that transitions from the characteristic camel shape with coarser representations to a more diffuse profile with finer representations.
Non-linear dynamics of compound sawteeth in tokamaks
Authors: Ahn J.-H. , Garbet X. , Lütjens H. , Marx A. , Nicolas T. , Sabot R. , Luciani J.-F. , Guirlet R. , Février O. , Maget P.
Published: May 2016

Compound sawteeth is studied with the XTOR-2F code. Non-linear full 3D magnetohydrodynamic simulations show that the plasma hot core is radially displaced and rotates during the partial crash, but is not fully expelled out of the q = 1 surface. Partial crashes occur when the radius of the q = 1 surface exceeds a critical value, at fixed poloidal beta. This critical value depends on the plasma elongation. The partial crash time is larger than the collapse time of an ordinary sawtooth, likely due to a weaker diamagnetic stabilization. This suggests that partial crashes result from a competition between destabilizing effects such as the q = 1 radius and diamagnetic stabilization.
Strong terahertz radiation generation by beating of two spatial-triangular beams in collisional magnetized plasma
Authors: Hematizadeh Ayoob , Bakhtiari Farhad , Jazayeri Seyed Masud , Ghafary Bijan
Published: May 2016

A scheme of terahertz (THz) radiation generation is proposed by beating of two spatial-triangular laser beams in plasma with a spatially periodic density when electron–neutral collisions have taken into account. In this process, the laser beams exert a ponderomotive force on the electrons of the plasma and impart the oscillatory velocity at the difference frequency in the presence of a static magnetic field which is applied parallel to the direction of the lasers. We show that higher efficiency and stronger THz radiation are achieved when the parallel magnetic field is used to compare the perpendicular magnetic field. The effects of beam width of lasers, collision frequency, periodicity of density ripples, and magnetic field strength are analyzed for strong THz radiation generation. The THz field of the emitted radiations is found to be highly sensitive to collision frequency and magnetic field strength. In this scheme with the optimization of plasma parameters, the efficiency of order 21% is achieved.
Tobacco Outlet Density and Attitudes Towards Smoking among Urban Adolescent Smokers
Authors: Mennis Jeremy , Mason Michael
Published: May 2016

Background: This study investigates whether residential exposure to tobacco outlets (i.e., convenience stores and other stores selling tobacco) is associated with attitudes towards smoking among a sample of urban, primarily African American, adolescent smokers. Methods: Cross-sectional survey data for 197 adolescents were integrated with spatial data on tobacco outlets via subject home addresses. Ordinal regression was employed to test hypotheses that closer proximity to, and higher concentrations of, tobacco outlets are associated with higher measures of intention to continue to smoke in the future, weaker self-efficacy related to stopping smoking, and more accepting social norms related to smoking, while controlling for characteristics of age, gender, family and peer smoking contexts, and level of nicotine dependence. Moderation by age and gender was also investigated. Results: Higher residential tobacco outlet density is significantly associated with a greater intention to smoke in the next 3 months, a lower readiness to stop smoking, and a greater likelihood of accepting a cigarette from a friend. Residential proximity to a tobacco outlet is significantly associated with a greater intention to smoke 5 years on. Evidence of a relationship between exposure to tobacco outlets and social norms related to smoking was not found, nor was there evidence for moderation of these relationships by age or gender. Conclusions: These results suggest that among urban adolescents who currently smoke, higher residential exposure to tobacco outlets is associated with greater predisposition towards future smoking and lower self-evaluation of the ability to stop smoking.
Anti-diabetic effects of luteolin and luteolin-7-O-glucoside on KK-Aymice
Authors: Zang Yanqing , Igarashi Kiharu , Li Yu
Published: May 2016

Anti-diabetic potential of luteolin (LU) and luteolin-7-O-glucoside (LUG) were investigated in the amount of equimolar on KK-Ay mice. The results showed that both of LU and LUG significantly improved blood glucose, HbA1c, insulin, and HOMR-IR levels. Anti-inflammatory and anti-oxidative effects of the LU and LUG were also proved. Furthermore, TGs in serum and liver were significantly decreased in the LU and LUG groups, as well as the mRNA expression of fat acid expression-related genes (SREBP-1c), compared to the basal diet group (CON). When compared the effects between the LU and LUG groups, TGs of the LU group were lower than those of the LUG group, accompanied with significantly decreased FAS activity and SREBP-1c expression in liver. These results suggested that both LU and LUG had positive effects of anti-diabetes on KK-Ay mice, but LU more potently ameliorated diabetes than LUG, which might be attributed to the inhibitory of lipid synthesis.
Evaluation of heat input during friction stir welding of aluminium alloys
Authors: Yi D. , Onuma T. , Mironov S. , Sato Y. S. , Kokawa H.
Published: May 2016

Heat input is one of the key parameters governing the quality and service properties of friction stir welds. By using a calorimetric technique, the heat inputs generated during the friction stir welding of the aluminium alloys, 1100 and 5083, were measured over a wide range of welding parameters. An empirical equation to estimate the heat input using the welding parameters was established based on a multiple regression analysis of the results. The effect of the heat input on the final grain size of the stir zone was also investigated by the electron backscatter diffraction method. The quantitative relationships between the input variables, heat inputs, and final grain sizes in the stir zone were derived.
The similarity of life across the universe
Authors: Cockell Charles S.
Published: May 2016

Is the hypothesis correct that if life exists elsewhere in the universe, it would have forms and structures unlike anything we could imagine? From the subatomic level in cellular energy acquisition to the assembly and even behavior of organisms at the scale of populations, life on Earth exhibits characteristics that suggest it is a universal norm for life at all levels of hierarchy. These patterns emerge from physical and biochemical limitations. Their potentially universal nature is supported by recent data on the astrophysical abundance and availability of carbon compounds and water. Within these constraints, biochemical and biological variation is certainly possible, but it is limited. If life exists elsewhere, life on Earth, rather than being a contingent product of one specific experiment in biological evolution, is likely to reflect common patterns for the assembly of living matter.
Quality of Interhospital Transfer Communication Practices and Association With Adverse Events on an Internal Medicine Hospitalist Service
Authors: Borofsky Jennifer S. , Bartsch Jason C. , Howard Alan B. , Repp Allen B.
Published: May 2016

Communication practices around interhospital transfer have not been rigorously assessed in adult medicine patients. Furthermore, the clinical implications of such practices have not been reported. This case–control study was designed to assess the quality of communication between clinicians during interhospital transfer and to determine if posttransfer adverse events (PTAEs) are associated with suboptimal communication. Cases included patients transferred to a Medicine Hospitalist Service from an outside hospital who subsequently experienced a PTAE, defined as unplanned transfer to an intensive care unit or death within 24 hours of transfer. Control patients also underwent interhospital transfer but did not experience a PTAE. A blinded investigator retrospectively reviewed the recorded pretransfer phone conversations between sending and receiving clinicians for adherence to a set of 13 empiric best practice communication elements. The primary outcome was the mean communication score, on a scale of 0–13. Mean scores between PTAE (8.3; 95% confidence interval [CI], 7.6–8.9) and control groups (7.9; 95% CI, 7.1–8.8) did not differ significantly (p = .50), although suboptimal communication on a subset of these elements was associated with increased PTAEs. Communication around interhospital transfer appears suboptimal compared with an empiric set of standard communication elements. Posttransfer adverse events were not associated with aggregate adherence to these standards.
Finding the Why, Changing the How: Improving the Mental Health of Medical Students, Residents, and Physicians
Authors: Slavin Stuart J. , Chibnall John T.
Published: May 2016

The poor mental health of residents, characterized by high rates of burnout, depression, and suicidal ideation, is a growing concern in graduate medical education. Research is needed to gain a deeper understanding of the sources of distress as well as the sources of sustenance in residency training. The study by Mata and colleagues contributes significantly to this understanding. In addition to this line of research, however, studies are needed that assess the impact of interventions to help residents deal more effectively with the stress of training and find meaning in their work. Given the stresses of residency training, this approach may not make a dramatic difference in mental health outcomes. Efforts directed at changing the educational and clinical environments are also needed to reduce unnecessary stressors and create more positive settings for learning and clinical care. Since 2011, Saint Louis University School of Medicine has been pursuing a multipronged strategy to address these issues in the preclinical years. These efforts have led to dramatic decreases in depression and anxiety symptoms in students. An essential component of these interventions is the ongoing measurement of mental health outcomes across all four years of the curriculum. Leaders of residency programs, medical schools, and hospitals need to have the courage to measure these kinds of outcomes to spur change and track the efficacy of programs.
In Their Own Words: An Analysis of the Experiences of Medical Interns Participating in a Prospective Cohort Study of Depression
Authors: Mata Douglas A. , Ramos Marco A. , Kim Michelle M. , Guille Constance , Sen Srijan
Published: May 2016

Purpose

To compare the subjective experiences of interns with and without symptoms of depression using a mixed-methods approach.

Method

In 2007–2008, interns from six institutions were screened for depression before and during internship using an online survey that included the Patient Health Questionnaire (PHQ-9). At the end of internship, participants were asked what made the year difficult, easy, and memorable, and how they had changed. Computerized lexical and qualitative thematic analyses were performed to analyze their free-text responses.

Results

Sixty-three percent (244/388) of invited interns participated in the original cohort study. Of those, 42% (103/244) answered the open-ended questions for this analysis. Thirty-five percent (36/103) screened positive for clinically significant depression (i.e., PHQ-9 score ≥ 10) during their intern year. Respondents with symptoms of depression were more likely to report problems with cynicism, exhaustion, and stress, while those without them were more likely to mention positive patient care and educational experiences. Respondents with symptoms of depression preferentially described experiences that “broke” their confidence, sense of well-being, and belief in the medical profession, while those who did not described profoundly positive, life-changing experiences regarding interactions with patients and supportive colleagues, through which they grew personally and professionally.

Conclusions

Depression during internship affects not only objective outcomes like medical errors but also how interns value the profession and themselves, with potentially profound consequences for their future career decisions. Residency programs should implement reactive interventions targeting depression and proactive interventions promoting resilience and well-being to address the issues that lead to depression.
The Priority of Intersectionality in Academic Medicine
Authors: Eckstrand Kristen L. , Eliason Jennifer , St.Cloud Tiffani , Potter Jennifer
Published: May 2016

Recent societal events highlight inequities experienced by underrepresented and marginalized communities. These inequities are the impetus for ongoing efforts in academic medicine to create inclusive educational and patient care environments for diverse stakeholders. Frequently, approaches focus on singular populations or broad macroscopic concepts and do not always elucidate the complexities that arise at the intersection between multiple identities and life experiences. Intersectionality acknowledges multidimensional aspects of identity inclusive of historical, structural, and cultural factors. Understanding how multiple identity experiences impact different individuals, from patients to trainees to providers, is critical for improving health care education and delivery. Building on existing work within academic medicine, this Commentary outlines six key recommendations to advance intersectionality in academic medicine: embrace personal and collective loci of responsibility; examine and rectify unbalanced power dynamics; celebrate visibility and intersectional innovation; engage all stakeholders in the process of change; select and analyze meaningful metrics; and sustain the commitment to achieving health equity over time. Members of the academic medical community committed to advancing health equity can use these recommendations to promote and maintain meaningful changes that recognize and respond to the multidimensional voices and expressed needs of all individuals engaged in providing and receiving health care.
Fulranumab in Patients With Pain Associated With Postherpetic Neuralgia and Postraumatic Neuropathy
Authors: Wang Hao , Romano Gary , Fedgchin Margaret , Russell Lucille , Sanga Panna , Kelly Kathleen M. , Frustaci Mary Ellen , Thipphawong John
Published: May 2016

Objective:

Fulranumab is an antibody that specifically neutralizes the biological activity of human nerve growth factor. This multicenter, phase-2, randomized, double-blind (DB), placebo-controlled study evaluated the analgesic efficacy and safety of fulranumab in postherpetic neuralgia (PHN) and posttraumatic neuropathy (PTN) patients.

Methods:

Patients (18 to 80 y) with inadequately controlled moderate-to-severe pain received study medication (subcutaneous injection) every 4 weeks. PHN patients were randomized (3:2:2:3) to receive either placebo or one of 3 doses of fulranumab: 1 mg (1 mgQ4 wk), 3 mg (3 mgQ4 wk), or 10 mg (10 mgQ4 wk). PTN patients were randomized (1:1) to receive either placebo or fulranumab 10 mgQ4 wk.

Results:

The US Food and Drug Administration placed a clinical hold (December 23, 2010) on all trials of antinerve growth factor drugs, including fulranumab, due to identified risks of osteonecrosis or rapidly progressing osteoarthritis; therefore, only 49 (of 150 planned) PHN patients and 34 (of 50 planned) PTN patients completed the DB efficacy evaluation. There was no significant difference (P>0.05, fulranumab vs. placebo) for change in 7-day average of daily pain intensity scores from DB baseline to end of 12-week DB efficacy phase in PHN or PTN patients (primary endpoint). No significant difference was found with fulranumab versus placebo (P>0.05) in other efficacy measures in either PHN or PTN patients. The most common treatment-emergent adverse events (>10% incidence) in PTN patients were sinusitis, carpal tunnel syndrome, and headache, whereas in PHN patients it was arthralgia.

Discussion:

Fulranumab did not demonstrate efficacy in either PHN or PTN patients, but was generally well-tolerated in this small underpowered and abbreviated study.
Continuous Positive Airway Pressure Mitigates Opioid-induced Worsening of Sleep-disordered Breathing Early after Bariatric Surgery
Authors: Zaremba Sebastian , Shin Christina H. , Hutter Matthew M. , Malviya Sanjana A. , Grabitz Stephanie D. , MacDonald Teresa , Diaz-Gil Daniel , Ramachandran Satya Krishna , Hess Dean , Malhotra Atul , Eikermann Matthias
Published: May 2016

AbstractAbstract

This prospective, randomized, cross over trial compared the apnea hypopnea index (AHI) with and without continuous positive airway pressure (CPAP) in 38 morbidly-obese patients and found that the CPAP reduced the AHI by 69% and was more effective during non-rapid eye movement sleep than during wakefulness. The AHI was worsened by self-administered opioid for pain and the CPAP application effectively mitigated the AHI deterioration.

Background

Bariatric surgery patients are vulnerable to sleep-disordered breathing (SDB) early after recovery from surgery and anesthesia. The authors hypothesized that continuous positive airway pressure (CPAP) improves postoperative oxygenation and SDB and mitigates opioid-induced respiratory depression.

Methods

In a randomized crossover trial, patients after bariatric surgery received 30% oxygen in the postanesthesia care unit (PACU) under two conditions: atmospheric pressure and CPAP (8 to 10 cm H2O). During 1 h of each treatment, breathing across cortical arousal states was analyzed using polysomnography and spirometry. Arousal state and respiratory events were scored in accordance with American Academy of Sleep Medicine guidelines. Data on opioid boluses in the PACU were collected. The primary and secondary outcomes were the apnea hypopnea index (AHI) and apnea after self-administration of opioids in the PACU. Linear mixed model analysis was used to compare physiologic measures of breathing.

Results

Sixty-four percent of the 33 patients with complete postoperative polysomnography data demonstrated SDB (AHI greater than 5/h) early after recovery from anesthesia. CPAP treatment decreased AHI (8 ± 2/h vs. 25 ± 5/h, P < 0.001), decreased oxygen desaturations (5 ± 10/h vs. 16 ± 20/h, P < 0.001), and increased the mean oxygen saturation by 3% (P = 0.003). CPAP significantly decreased the respiratory-depressant effects observed during wakefulness–sleep transitions without affecting hemodynamics. The interaction effects between CPAP treatment and opioid dose for the dependent variables AHI (P < 0.001), inspiratory flow (P = 0.002), and minute ventilation (P = 0.015) were significant.

Conclusions

This pharmacophysiologic interaction trial shows that supervised CPAP treatment early after surgery improves SDB and ameliorates the respiratory-depressant effects of opioids without undue hemodynamic effects.
Restrictive versus Liberal Transfusion Strategy in the Perioperative and Acute Care Settings
Authors: Hovaguimian Frédérique , Myles Paul S.
Published: May 2016

AbstractAbstract

In a review of 31 trials grouped into 5 context-specific strata, restrictive transfusion strategies increased the risk of mortality and composite morbidity in patients undergoing cardiac/vascular procedures and in elderly orthopedic patients.

Supplemental Digital Content is available in the text.

Background

Blood transfusions are associated with morbidity and mortality. However, restrictive thresholds could harm patients less able to tolerate anemia. Using a context-specific approach (according to patient characteristics and clinical settings), the authors conducted a systematic review to quantify the effects of transfusion strategies.

Methods

The authors searched MEDLINE, EMBASE, CENTRAL, and grey literature sources to November 2015 for randomized controlled trials comparing restrictive versus liberal transfusion strategies applied more than 24 h in adult surgical or critically ill patients. Data were independently extracted. Risk ratios were calculated for 30-day complications, defined as inadequate oxygen supply (myocardial, cerebral, renal, mesenteric, and peripheral ischemic injury; arrhythmia; and unstable angina), mortality, composite of both, and infections. Statistical combination followed a context-specific approach. Additional analyses explored transfusion protocol heterogeneity and cointerventions effects.

Results

Thirty-one trials were regrouped into five context-specific risk strata. In patients undergoing cardiac/vascular procedures, restrictive strategies seemed to increase the risk of events reflecting inadequate oxygen supply (risk ratio [RR], 1.09; 95% CI, 0.97 to 1.22), mortality (RR, 1.39; 95% CI, 0.95 to 2.04), and composite events (RR, 1.12; 95% CI, 1.01 to 1.24—3322, 3245, and 3322 patients, respectively). Similar results were found in elderly orthopedic patients (inadequate oxygen supply: RR, 1.41; 95% CI, 1.03 to 1.92; mortality: RR, 1.09; 95% CI, 0.80 to 1.49; composite outcome: RR, 1.24; 95% CI, 1.00 to 1.54—3465, 3546, and 3749 patients, respectively), but not in critically ill patients. No difference was found for infections, although a protective effect may exist. Risk estimates varied with successful/unsuccessful transfusion protocol implementation.

Conclusions

Restrictive transfusion strategies should be applied with caution in high-risk patients undergoing major surgery.
Compassion Competence in Nurses
Authors: Lee Youngjin , Seomun GyeongAe
Published: May 2016

The purpose of study was to identify the attributes of the concept of compassion competence for nurses. A hybrid model was used to develop the concept, which included fieldwork performed. The concept of compassion competence was found to possess 3 dimensions: (a) acquisition of a wealth of knowledge; (b) development of skills of emotional communication, sensitivity, insight, and self-regulation; and (c) development of attitudes of respect and empathy, and maintenance of occupational distance. Compassion competence could be useful for developing ways to enhance the knowledge, skills, and attitudes required for nurses to provide compassionate care in various nursing practices.
An Exploratory Descriptive Study on Task Shifting in East Africa
Authors: Spies Lori A.
Published: May 2016

The purpose of this study was to explore the perceptions of nurse leaders in Ethiopia, Kenya, Tanzania, and Uganda who have taken on expanded roles through task shifting. Understanding how nurses perceive task shifting directs education and training to more effectively meet population health needs in their communities. Participants were nurse leaders in countries with complex health care systems and few resources. Participants identified conflicting roles and expectations that were not consistent with their role preparation or scope of practice.
Relationship Power in the Context of Heterosexual Intimate Relationships
Authors: Halstead Valerie , De Santis Joseph , Williams Jessica
Published: May 2016

Various theoretical frameworks have been utilized while examining the concept of relationship power. In addition, the conceptual definition and operational use are inconsistent throughout literature. A concept analysis was conducted on the basis of the guidelines provided by Walker and Avant. The proposed definition of relationship power is the relative, perceived, and actual ability to influence a relationship partner. Antecedents, attributes, and consequences are presented. Because of the various adverse outcomes related to relationship power (eg, intimate partner violence, depression), an understanding of this concept is essential. Furthermore, a clear understanding is needed to advance nursing knowledge, leading to future research and theory development.
A Decolonizing Methodology for Health Research on Female Genital Cutting
Authors: Werunga Jane , Reimer-Kirkham Sheryl , Ewashen Carol
Published: May 2016

In this article, critical perspectives including postcolonial feminism, African feminism, and intersectionality are presented as having decolonizing methodological potential whereby the Western narrative surrounding the practice of female genital cutting, particularly in the context of migration, is reexamined. In addition, multiple intersecting influences on affected women's realities are accounted for and a critical consciousness that serves to inform praxis, address social determinants of health, and promote health equity is encouraged. The inclusion of an African feminist perspective, a traditionally marginalized critical perspective, serves to further decolonize some long-held erroneous beliefs about the sexuality, subjectivity, and embodiment of the African woman.
Varicella zoster virus triggers the immunopathology of giant cell arteritis
Authors: Gilden Don , Nagel Maria A.
Published: May 2016

Purpose of review

Giant cell arteritis (GCA) is a severe form of vasculitis in the elderly. The recent discovery of varicella zoster virus (VZV) in the temporal arteries and adjacent skeletal muscle of patients with GCA, and the rationale and strategy for antiviral and corticosteroid treatment for GCA are reviewed.

Recent findings

The clinical features of GCA include excruciating headache/head pain, often with scalp tenderness, a nodular temporal arteries and decreased temporal artery pulsations. Jaw claudication, night sweats, fever, malaise, and a history of polymyalgia rheumatica (aching and stiffness of large muscles primarily in the shoulder girdle, upper back, and pelvis without objective signs of weakness) are common. ESR and CRP are usually elevated. Diagnosis is confirmed by temporal artery biopsy which reveals vessel wall damage and inflammation, with multinucleated giant cells and/or epithelioid macrophages. Skip lesions are common. Importantly, temporal artery biopsies are pathologically negative in many clinically suspect cases. This review highlights recent virological findings in temporal arteries from patients with pathologically verified GCA and in temporal arteries from patients who manifest clinical and laboratory features of GCA, but whose temporal artery biopsies (Bx) are pathologically negative for GCA (Bx-negative GCA). Virological analysis revealed that VZV is present in most GCA-positive and GCA-negative temporal artery biopsies, mostly in skip areas that correlate with adjacent GCA pathology.

The presence of VZV in Bx-positive and Bx-negative GCA temporal arteries indicates that VZV triggers the immunopathology of GCA. However, the presence of VZV in about 20% of temporal artery biopsies from non-GCA postmortem controls also suggests that VZV alone is not sufficient to produce disease. Treatment trials should be performed to determine if antiviral agents confer additional benefits to corticosteroids in both Bx-positive and Bx-negative GCA patients. These studies should also examine whether oral antiviral agents and corticosteroids are as effective as intravenous acyclovir and corticosteroids. Appropriate dosage and duration of treatment also remain to be determined.
Ankylosing spondylitis: beyond genome-wide association studies
Authors: O’Rielly Darren D. , Uddin Mohammed , Rahman Proton
Published: May 2016

Purpose of review

This article discusses genomic investigations in ankylosing spondylitis (AS) beyond genome-wide association (GWA) studies, but prior to this, genetic variants achieving genome-wide significance will be summarized highlighting key pathways contributing to disease pathogenesis.

Recent findings

Evidence suggests that disease pathogenesis is attributed to a complex interplay of genetic, environmental and immunological factors. GWA studies have greatly enhanced our understanding of AS pathogenesis by illuminating distinct immunomodulatory pathways affecting innate and acquired immunity, most notably the interleukin-23/interleukin-17 pathway. However, despite the wealth of new information gleaned from such studies, a fraction of the heritability (24.4%) has been explained. This review will focus on investigations beyond GWA studies including copy number variants, gene expression profiling, including microRNA (miRNA), epigenetics, rare variants and gene–gene interactions.

To address the ‘missing heritability’ and advance beyond GWA studies, a concerted effort involving rethinking of study design and implementation of newer technologies will be required. The coming of age of next-generation sequencing and advancements in epigenetic and miRNA technologies, combined with familial-focused investigations using well-characterized cohorts, is likely to reveal some of the hidden genomic mysteries associated with AS.
The interaction between host genetics and the microbiome in the pathogenesis of spondyloarthropathies
Authors: Asquith Mark , Rosenbaum James T.
Published: May 2016

Purpose of review

The intestinal microbiome is increasingly implicated in the pathogenesis of ankylosing spondylitis, reactive arthritis, and other diseases collectively known as the spondyloarthropathies (SpAs). In common with other complex inflammatory diseases, SpAs have both a strong genetic and environmental component. Recent genetic studies have highlighted host pathways that may intersect the host–microbiota interaction and offer novel paradigms to understand the pathophysiology of these diseases.

Recent findings

Genetic association studies have identified genes such as RUNX3, PTPEN2, and IL-33 as susceptibility loci for SpAs. Functional studies in humans have extended knowledge of established genetic risk factors for ankylosing spondylitis that include ERAP1, ERAP2, and interleukin-23R. Recent basic research has identified new mechanisms that regulate host immune responses to the microbiota that conceivably may be dysregulated in SpA.

Intestinal barrier function, deletional tolerance, Th17 signature response, and endoplasmic reticulum stress pathways have been recently linked to SpA. Dysregulated immune responses to the gut microbiota and an altered microbial community structure are shared features of SpA. Although the cause-effect dynamic of this relationship remains equivocal, it nonetheless has major implications for both intestinal and extra-intestinal pathology observed in SpA.
FRAX updates 2016
Authors: McCloskey Eugene V. , Harvey Nicholas C. , Johansson Helena , Kanis John A.
Published: May 2016

Purpose of review

In the 8 years since the launch of the FRAX tool, it has continued to grow with the addition of new country or territory models. Although the core of the fracture risk algorithm remains unchanged, there is growing evidence of possible additional independent clinical variables that might modulate the interpretation of the FRAX outputs. There is also an expanding number of international guidelines that incorporate FRAX assessments, leading to discussions on the use of FRAX in treated patients and the determination of intervention thresholds.

Recent findings

This review encompasses recent information on the use of FRAX in immigrant populations and the potential influence of skeletal and extraskeletal risk factors on FRAX estimations. For example, trabecular bone score and falls risk appear to be promising additional factors in individual risk assessment. FRAX appears to remain accurate in those on osteoporosis treatments, but FRAX is not a suitable tool for use in treat-to-target strategies.

The assessment of fracture risk in immigrants is probably more accurate with the use of the FRAX tool for the country of origin, if available. The impact of additional risk variables will need evaluation of the impact of these on recharacterizing patients by moving them across intervention thresholds.
Flexible Intramedullary Nailing of Pediatric Humeral Fractures: Indications, Techniques, and Tips
Authors: Kelly Derek M.
Published: May 2016

Most proximal and diaphyseal pediatric humeral fractures can be treated successfully by closed means; however, certain patient factors or fracture characteristics may make surgical stabilization with flexible intramedullary nails (FIN) a better choice. Common indications for FIN of pediatric humeral fractures include unstable proximal-third fractures in children nearing skeletal maturity, unstable distal metaphyseal-diaphyseal junction fractures, shaft fractures in polytraumatized patients or patients with ipsilateral both-bone forearm fractures (floating elbow), and prophylactic stabilization of benign diaphyseal bone cysts or surgical stabilization of pathologic fractures. FIN can be safely inserted in an antegrade or retrograde manner depending on the fracture location and configuration. Careful dissection at the location of rod insertion can prevent iatrogenic nerve injuries. Rapid fracture union and return to full function can be expected in most cases. Implant prominence is the most common complication.
Do Lumbar Decompression and Fusion Patients Recall Their Preoperative Status?
Authors: Aleem Ilyas S. , Duncan Jonathan , Ahmed Amin M. , Zarrabian Mohammad , Eck Jason , Rhee John , Clarke Michelle , Currier Bradford L. , Nassr Ahmad
Published: May 2016

Study Design.

Prospective cohort study.

Objective.

To characterize the accuracy of patient recollection of preoperative symptoms after lumbar spine surgery.

Summary of Background Data.

Although patient-reported outcomes have become important in the evaluation of spine surgery patients, the accuracy of patient recall remains unknown.

Methods.

Patients undergoing lumbar decompression with or without fusion were enrolled. Back and leg Numeric Pain Scores and Oswestry Disability Indices were recorded preoperatively. Patients were asked to recall their preoperative status at a minimum of 1 year after surgery. Actual and recalled scores were compared using paired t tests and relations were quantified using Pearson correlation coefficients. Multivariable linear regression was used to identify factors that affected recollection.

Results.

Sixty-two patients with a mean age of 66.1 years were included. Compared to their preoperative scores, patients showed significant improvement in back pain (mean difference [MD] = −3.2, 95% CI −4.0 to −2.4), leg pain (MD −3.3, 95% CI −4.3 to −2.2), and disability (MD −25.0%, 95% CI −28.7 to −19.6). Patient recollection of preoperative status was significantly more severe than actual for back pain (MD +2.3, 95% CI 1.5–3.2), leg pain (MD +1.8, 95% CI 0.9–2.7), and disability (MD +9.6%, 95% CI 5.6–14.0). No significant correlation between actual and recalled scores with regards to back (r = 0.18) or leg (r = 0.24) pain and only moderate correlation with disability (r = 0.44) were seen. This was maintained across age, sex, and time between date of surgery and recollection. More than 40% of patients switched their predominant symptom from back pain to leg pain or leg pain to back pain on recall.

Conclusion.

Relying on patient recollection does not provide an accurate measure of preoperative status after lumbar spine surgery. Recall bias indicates the importance of obtaining true baseline scores and patient-reported outcomes prospectively and not retrospectively.

Level of Evidence: 2
Wedge-Shaped Resection of the Posterior Bony Arch During Open Door Laminoplasty to Prevent Postoperative Motion Limitation
Authors: Suh Bo-Gun , Ahn Myun-Whan , Kim Ho-Joong , Yeom Jin S. , Lee Gun Woo
Published: May 2016

Study Design.

Prospective randomized double-arm noninferiority study.

Objective.

To evaluate an additional surgical procedure (wedge-shaped resection of the cranial portion of the posterior bony arch) during open-door laminoplasty (ODLP), and to compare the outcomes with those of conventional ODLP surgery.

Summary of Background Data.

In clinical practice, spine surgeons sometimes encounter patients who show bony impingement on lateral radiographs after ODLP; bony impingement may lead to reduced motion of the cervical spine and posterior neck pain. However, this problem has not been well studied, and no methods have been developed to prevent it.

Methods.

Of total 79 patients, 75 were enrolled and randomly assigned to either group A (additional procedure in ODLP, n = 38) or group B (ODLP alone, n = 37). The primary outcome measure was range of motion (ROM) of the cervical spine. Secondary endpoints included clinical outcomes based on pain intensity, 12-item short form health survey (SF-12), and modified Japanese Orthopedic Association scale; presence of bony impingement on dynamic lateral radiographs; surgical outcomes; and surgery-related complications.

Results.

ROM of the cervical spine was significantly greater at 6 months (P = 0.04) and 1 year (P = 0.02) postoperative in group A than in group B. Pain intensity at the posterior neck was significantly lower 1 year after surgery in group A than in group B (P = 0.03). In lateral radiographs 1 year after surgery, the presence of posterior bony impingement was 0% in group A and 32.4% in group B (P <0.01). Clinical outcomes and surgery-related complications were similar between groups.

Conclusion.

Performing wedge-shaped resection of the cranial portion of the posterior bony arch in ODLP surgery can lead to better outcomes than ODLP alone in terms of preservation of cervical ROM, prevention of posterior bony impingement, and amelioration of posterior neck pain.

Level of Evidence: 2
Historical Perspective: Henry H. Bohlman (1937–2010)
Authors: Abola Matthew V. , Knapik Derrick M. , Gordon Zachary L. , Furey Christopher G. , Marcus Randall E.
Published: May 2016

The incredible career of Henry H. Bohlman, MD, spanned over four decades at University Hospitals Case Medical Center. He was an innovator and pioneer, designing several techniques for the management of several spinal pathologies while advocating the anterior approach to the spine. Dr. Bohlman's legacy is preserved in his fellows who have become leaders in spine surgery throughout the world.