bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of torsion and stretching on the thermal conductivity of polyethylene strands
Authors: Tu Runchun , Liao Quanwen , Zeng Lingping , Liu Zhichun , Liu Wei
Published: March 2017

A single polyethylene chain was reported to have a high metal-like thermal conductivity (TC), which stands in sharp contrast to the thermally insulating feature of common bulk polyethylene materials. This work numerically investigates the impact of torsion and stretching on the TC of polyethylene strands by using equilibrium molecular dynamics simulations. The simulation results show that torsion slightly reduces the TC of a single polyethylene chain. In contrast, the heat conduction of polyethylene strands could be slightly enhanced under torsional loading with a specific torsional angle. Particularly, an apparent improvement of TC of polyethylene strands is achieved by combining torsion and stretching functions. It is found that the TC of torsional polyethylene strands is sensitive to torsional patterns. Our study proposes a specific torsional pattern of polyethylene strands that significantly enhances the heat conduction of the original counterpart. This study will play an essential role in guiding the improvements of thermal conduction property of polymers.
Photoswitching of azobenzene-containing self-assembled monolayers as a tool for control over silicon surface electronic properties
Authors: Malyar Ivan V. , Titov Evgenii , Lomadze Nino , Saalfrank Peter , Santer Svetlana
Published: March 2017

We report on photoinduced remote control of work function and surface potential of a silicon surface modified with a photosensitive self-assembled monolayer consisting of chemisorbed azobenzene molecules (4-nitroazobenzene). It was found that the attachment of the organic monolayer increases the work function by hundreds of meV due to the increase in the electron affinity of silicon substrates. The change in the work function on UV light illumination is more pronounced for the azobenzene jacketed silicon substrate (ca. 250 meV) in comparison to 50 meV for the unmodified surface. Moreover, the photoisomerization of azobenzene results in complex kinetics of the work function change: immediate decrease due to light-driven processes in the silicon surface followed by slower recovery to the initial state due to azobenzene isomerization. This behavior could be of interest for electronic devices where the reaction on irradiation should be more pronounced at small time scales but the overall surface potential should stay constant over time independent of the irradiation conditions.
Communication: Nonadditive dielectric susceptibility spectra of associating liquids
Authors: Bierwirth S. P. , Münzner P. , Knapp T. A. , Gainaru C. , Böhmer R.
Published: March 2017

Highly unusual linear-response spectra involving contributions from hydrogen-bonded supramolecular processes and from structural relaxations are found in 4-methyl-3-heptanol mixed with 2-ethyl-1-hexylbromide. Although the mean time scales of the underlying relaxations are separated by more than 3 decades, the overall spectra cannot be decomposed into a sum of these processes. This finding challenges the ubiquitous practice of disentangling susceptibility spectra of Debye liquids by adding suitable subspectra. The spectral shape of the studied viscous mixtures is excellently described using the Williams ansatz, here a necessary approach and not as previously considered merely an alternative to additive analyses.
Characterization of the hydrogen-bond network of water around sucrose and trehalose: Microwave and terahertz spectroscopic study
Authors: Shiraga Keiichiro , Adachi Aya , Nakamura Masahito , Tajima Takuro , Ajito Katsuhiro , Ogawa Yuichi
Published: March 2017

Modification of the water hydrogen bond network imposed by disaccharides is known to serve as a bioprotective agent in living organisms, though its comprehensive understanding is still yet to be reached. In this study, aiming to characterize the dynamical slowing down and destructuring effect of disaccharides, we performed broadband dielectric spectroscopy, ranging from 0.5 GHz to 12 THz, of sucrose and trehalose aqueous solutions. The destructuring effect was examined in two ways (the hydrogen bond fragmentation and disordering) and our result showed that both sucrose and trehalose exhibit an obvious destructuring effect with a similar strength, by fragmenting hydrogen bonds and distorting the tetrahedral-like structure of water. This observation strongly supports a chaotropic (structure-breaking) aspect of disaccharides on the water structure. At the same time, hydration water was found to exhibit slower dynamics and a greater reorientational cooperativity than bulk water because of the strengthened hydrogen bonds. These results lead to the conclusion that strong disaccharide–water hydrogen bonds structurally incompatible with native water–water bonds lead to the rigid but destructured hydrogen bond network around disaccharides. Another important finding in this study is that the greater dynamical slowing down of trehalose was found compared with that of sucrose, at variance with the destructuring effect where no solute dependent difference was observed. This discovery suggests that the exceptionally greater bioprotective impact especially of trehalose among disaccharides is mainly associated with the dynamical slowing down (rather than the destructuring effect).
Laser induced white emission generated by infrared excitation from Eu3+:Sr2CeO4 nanocrystals
Authors: Stefanski M. , Lukaszewicz M. , Hreniak D. , Strek W.
Published: March 2017

The laser induced white emission (LIWE) was observed from Eu3+:Sr2CeO4 nanocrystals. The samples were obtained in form of powders by the modified sol-gel route. The structure and morphology of the phosphors were investigated by powder X-ray diffraction and transmission electron microscope techniques. The intense LIWE occurred under reduced pressure and focused beam of near infrared laser excitation. The power and pressure dependencies exhibit evident threshold character typical for the avalanche effect. The photoconductivity of the Eu3+:Sr2CeO4 nanocrystals measured as a function of different powers of excitation source was analyzed.
Predicting transport regime and local electrostatic environment from Coulomb blockade diamond sizes
Authors: Olsen Stine T. , Hansen Thorsten , Mikkelsen Kurt V.
Published: March 2017

Electron transport through a molecule is often described in one of the two regimes: the coherent tunnelling regime or the Coulomb blockade regime. The twilight zone of the two regimes still possesses many unsolved questions. A theoretical analysis of the oligophenylenevinylene OPV3 experiments by Bjørnholm and co-workers is performed. The experiments showed how two OPV3 derivatives performed very differently despite the strong similarity of the molecular structure, hence the experimental data showed two different transport mechanisms. The different transport mechanisms of the two OPV3 derivatives are explained from quantum mechanical calculations of the molecular redox energies and from the experimentally accessible window size.
Scavenging of oxygen from SrTiO3 during oxide thin film deposition and the formation of interfacial 2DEGs
Authors: Posadas Agham B. , Kormondy Kristy J. , Guo Wei , Ponath Patrick , Geler-Kremer Jacqueline , Hadamek Tobias , Demkov Alexander A.
Published: March 2017

SrTiO3 is a widely used substrate for the growth of other functional oxide thin films. The reactivity of the substrate with respect to the film during deposition, particularly with regard to redox reactions, has typically been glossed over. We demonstrate by depositing a variety of metals (Ti, Al, Nb, Pt, Eu, and Sr) and measuring the in situ core level spectra of both the metal and SrTiO3 that, depending on the oxide formation energy and work function of the metal, three distinct types of behavior occur in thin metal films on SrTiO3 (100). In many cases, there will be an interfacial layer of oxygen-deficient SrTiO3 formed at the interface with the overlying film. We discuss how this may affect the interpretation of the well-known two-dimensional electron gas present at the interface between SrTiO3 and various oxides.
Low-frequency guided waves in a fluid-filled borehole: Simultaneous effects of generation and scattering due to multiple fractures
Authors: Minato Shohei , Ghose Ranajit
Published: March 2017

Low-frequency, axially-symmetric guided waves which propagate along a fluid-filled borehole (tube waves) are studied in order to characterize the hydraulic fractures intersecting the borehole. We formulate a new equation for the total tube wavefield, which includes simultaneous effects of (1) tube-wave scattering (reflection and transmission) due to wave propagation across hydraulic fractures, and (2) tube-wave generation due to incident plane P waves. The fracture is represented by the nonwelded interface boundary conditions. We use an appropriate form of the representation theorem in order to correctly handle the multiple scattering due to nonwelded interfaces. Our approach can implement any model that has so far been developed. We consider a recent model which includes simultaneous effects of fluid viscosity, dynamic fluid flow, and fracture compliance. The derived equation offers a number of important insights. We recognize that the effective generation amplitude contains the simultaneous effect of both tube-wave generation and scattering. This leads to a new physical understanding indicating that the tube waves are scattered immediately after generation. We show that this scattering is nonlinear with respect to interface compliance. This physical mechanism can be implicitly accounted for by considering more realistic boundary conditions. We also illustrate the application of the new equation in order to predict the complex signature of the total tube wavefield, including generation and scattering at multiple hydraulic fractures. A new formulation for focusing analyses is also derived in order to image and characterize the hydraulic fractures. The obtained results and discussions are important for interpretation, modeling, and imaging using low-frequency guided waves, in the presence of multiple fractures along a cylindrical inclusion.
Charge transfer-induced magnetic exchange bias and electron localization in (111)- and (001)-oriented LaNiO3/LaMnO3 superlattices
Authors: Wei Haoming , Barzola-Quiquia Jose Luis , Yang Chang , Patzig Christian , Höche Thomas , Esquinazi Pablo , Grundmann Marius , Lorenz Michael
Published: March 2017

High-quality lattice-matched LaNiO3/LaMnO3 superlattices with monolayer terrace structure have been grown on both (111)- and (001)-oriented SrTiO3 substrates by pulsed laser deposition. In contrast to the previously reported experiments, a magnetic exchange bias is observed that reproducibly occurs in both (111)- and (001)-oriented superlattices with the thin single layers of 5 and 7 unit cells, respectively. The exchange bias is theoretically explained by charge transfer-induced magnetic moments at Ni atoms. Furthermore, magnetization data at low temperature suggest two magnetic phases in the superlattices, with Néel temperature around 10 K. Electrical transport measurements reveal a metal-insulator transition with strong localization of electrons in the superlattices with the thin LaNiO3 layers of 4 unit cells, in which the electrical transport is dominated by two-dimensional variable range hopping.
A thermodynamic potential and the temperature-composition phase diagram for single-crystalline K1-xNaxNbO3 (0 ≤ x ≤ 0.5)
Authors: Pohlmann Hannah , Wang Jian-Jun , Wang Bo , Chen Long-Qing
Published: March 2017

Environment-friendly lead-free piezoelectric materials, such as the niobate perovskite compound (K1-xNaxNbO3), have attracted increasing attention over the last decade. Although extensive efforts have been made to study these materials experimentally, there have been much fewer theoretical studies on the microstructural evolution and property optimization of lead-free systems due to the lack of a comprehensive thermodynamic assessment. In this study, we first established a general procedure for constructing thermodynamic potentials for ferroelectric systems. We then developed an eighth-order Landau thermodynamic potential for K1-xNaxNbO3 (0 ≤ x ≤ 0.5) single crystals, taking into account the low temperature quantum mechanical effects. Based on this potential, we computed the spontaneous polarization and the dielectric constants for each composition as well as an overall temperature-composition phase diagram, all of which agree well with the available experimental data.
Nano concentration by acoustically generated complex spiral vortex field
Authors: Tang Qiang , Wang Xiaofei , Hu Junhui
Published: March 2017

A strategy to concentrate nanoscale materials on the boundary between a nano suspension droplet and non-vibration substrate is demonstrated and analyzed. It employs the spiral vortex of acoustic streaming, generated by an ultrasonically vibrating needle parallel to and above the non-vibration substrate. The vortex drags nanoscale materials to the center of itself, forming a concentration spot. For 250 nm-diameter SiO2 nano particle suspension with an initial concentration of 0.09 mg/ml, the diameter of the concentration spot can be up to several hundred microns. The dependency of the spiral vortex field on the vibration distribution of the acoustic needle in the droplet is also clarified by experiments and computation, and the concentration conditions are obtained by analyzing the nano particle dynamics in the spiral vortex.
The influences of surface plasmons and thermal effects on femtosecond laser-induced subwavelength periodic ripples on Au film by pump-probe imaging
Authors: Zhou Kan , Jia Xin , Jia Tianqing , Cheng Ke , Cao Kaiqiang , Zhang Shian , Feng Donghai , Sun Zhenrong
Published: March 2017

In this paper, the influences of surface plasmons and thermal effects on the formation of subwavelength periodic ripples on Au films irradiated by 800 nm femtosecond laser pulses were studied by collinear pump-probe imaging. The spatial and temporal resolutions of the experiment were 300 nm and 1 ps, respectively. No periodic ripples were observed on the Au film during ablation by the first pump pulse, but during ablation by the second pump pulse the appearance of transient ripples was evident from a delay time of hundreds of picoseconds to several nanoseconds. These ripples, however, were not retained after solidification. When the sample was immersed in water during ablation, however, the ripples were retained. It is proposed that, during the second laser pulse irradiation, the surface defects produced by the first pulse induced surface plasmon polaritons on the Au film, which caused a modulated energy deposition and the formation of transient ripples. The weak electron–phonon coupling and significant residual heat erase these ripples after the molten surface was solidified.
Acetonitrile cluster solvation in a cryogenic ethane-methane-propane liquid: Implications for Titan lake chemistry
Authors: Corrales L. René , Yi Thomas D. , Trumbo Samantha K. , Shalloway David , Lunine Jonathan I. , Usher David A.
Published: March 2017

The atmosphere of Titan, Saturn’s largest moon, exhibits interesting UV- and radiation-driven chemistry between nitrogen and methane, resulting in dipolar, nitrile-containing molecules. The assembly and subsequent solvation of such molecules in the alkane lakes and seas found on the moon’s surface are of particular interest for investigating the possibility of prebiotic chemistry in Titan’s hydrophobic seas. Here we characterize the solvation of acetonitrile, a product of Titan’s atmospheric radiation chemistry tentatively detected on Titan’s surface [H. B. Niemann et al., Nature 438, 779–784 (2005)], in an alkane mixture estimated to match a postulated composition of the smaller lakes during cycles of active drying and rewetting. Molecular dynamics simulations are employed to determine the potential of mean force of acetonitrile (CH3CN) clusters moving from the alkane vapor into the bulk liquid. We find that the clusters prefer the alkane liquid to the vapor and do not dissociate in the bulk liquid. This opens up the possibility that acetonitrile-based microscopic polar chemistry may be possible in the otherwise nonpolar Titan lakes.
Maturity, Spawning Omission, and Reproductive Complexity of Deepwater Rockfish
Authors: Conrath Christina Lyn
Published: March 2017

Reproductive parameters are critical components of stock assessment models that directly influence estimates of the stock biomass of mature females and significantly impact the determination of catch levels for many federally managed fish species. There are few data available concerning the reproductive biology of deepwater rockfish species in the Gulf of Alaska, which are suspected to have complex life histories that include viviparity, increasing productivity with age, abortive maturity, and spawning omission. The objective of this study was to examine the reproductive biology of female Shortraker Rockfish Sebastes borealis, Rougheye Rockfish S. aleutianus, and Blackspotted Rockfish S. melanostictus within the Gulf of Alaska. The reproductive development stage was examined for samples collected opportunistically throughout the year from a variety of scientific platforms and charter vessels in 2008–2014. Rougheye Rockfish and Shortraker Rockfish were found to be seasonal synchronous spawners, with the onset of development occurring in the later summer months and parturition taking place from March through May. The fork length at 50% maturity (L50) was similar for Rougheye Rockfish (L50 = 45.0 cm) and Blackspotted Rockfish (L50 = 45.3 cm), but the age at 50% maturity (A50) was younger for Rougheye Rockfish (A50 = 19.6 years) than for Blackspotted Rockfish (A50 = 27.4 years). The L50 for Shortraker Rockfish was 49.9 cm, but this species could not be reliably aged. In all three species, there were individuals undergoing abortive maturity and skipped spawning. Skipped spawning rates ranged from 37.4% (95% confidence interval [CI] = 29.9–44.9%) for Rougheye Rockfish to 93.9% (95% CI = 90.0–97.3%) for Blackspotted Rockfish; Shortraker Rockfish had an intermediate skipped spawning rate of 60.0% (95% CI = 49.2–70.8%). The results from this study will advance our knowledge of the reproductive biology of these species and will aid in ensuring that the most appropriate data are utilized in their stock assessments.

Received August 17, 2016; accepted January 18, 2017 Published online March 24, 2017
Influence of Size, Age, and Spawning Season on Sex Change in Black Sea Bass
Authors: Provost M. M. , Jensen O. P. , Berlinsky D. L.
Published: March 2017

A tagging study was conducted off the New Jersey coast to study sex change in Black Sea Bass Centropristis striata as a function of size, age, and spawning season. Throughout 2011–2013, 3,670 fish were measured and 1,498 were tagged from research, charter, and commercial fishing vessels. Of the tagged fish, 437 were recaptured. Size at 50% probability of sex change was 355 mm TL; the proportion of female fish in sexual transition increased with body size from 0.5% at 175–225 mm to 15.7% at 375–425 mm and increased with age from 0.6% at 3 years old to 18.2% at 6 years old. Relatively few females (8 of 107) changed sex during the spawning season, but a larger proportion (8 of 22 females) transitioned between spawning seasons. The proportion of females with transitional gonads was lowest at the start of the spawning season in June (0.2%), slowly increased over the summer, and sharply peaked just after the spawning season in October (9.5%). In addition, a high proportion of young mature fish were male (40% at age 2), which may indicate the presence of primary males. This is the first tagging study to estimate sex change as a function of size, age, and season in a protogynous hermaphroditic fish species. Use of tagging avoids potential problems that are associated with inferring sex change rates from sex ratios based on catch data.
EthSEQ: ethnicity annotation from whole exome sequencing data
Authors: Romanel Alessandro , Zhang Tuo , Elemento Olivier , Demichelis Francesca
Published: March 2017

Whole exome sequencing (WES) is widely utilized both in translational cancer genomics studies and in the setting of precision medicine. Stratification of individual’s ethnicity is fundamental for the correct interpretation of personal genomic variation impact. We implemented EthSEQ to provide reliable and rapid ethnicity annotation from whole exome sequencing individual’s data, validated it on 1000 Genome Project and TCGA data (2700 samples) demonstrating high precision, and finally assessed computational performances compared to other tools. EthSEQ can be integrated into any WES based processing pipeline and exploits multi-core capabilities.

Availability and Implementation

R package available at github.com/aromanel/EthSEQ and CRAN repository.

Supplementary information

Supplementary data are available at Bioinformatics online.
Local Group ultra-faint dwarf galaxies in the reionization era
Authors: Weisz Daniel R. , Boylan-Kolchin Michael
Published: March 2017

Motivated by the stellar fossil record of Local Group (LG) dwarf galaxies, we show that the star-forming ancestors of the faintest ultra-faint dwarf galaxies (UFDs; MV ∼ −2 or M⋆ ∼ 102 at z = 0) had ultraviolet (UV) luminosities of MUV ∼ −3 to −6 during reionization (z ∼ 6–10). The existence of such faint galaxies has substantial implications for early epochs of galaxy formation and reionization. If the faint-end slopes of the UV luminosity functions (UVLFs) during reionization are steep (α ≲ −2) to MUV ∼ −3, then (i) the ancestors of UFDs produced >50 per cent of UV flux from galaxies; (ii) galaxies can maintain reionization with escape fractions that are more than two times lower than currently adopted values; (iii) direct Hubble Space Telescope and James Webb Space Telescope observations may detect only ∼10–50 per cent of the UV light from galaxies; and (iv) the cosmic star formation history increases by ≳ 4–6 at z ≳ 6. Significant flux from UFDs, and resultant tensions with LG dwarf galaxy counts, is reduced if the high-redshift UVLF turns over. Independent of the UVLF shape, the existence of a large population of UFDs requires a non-zero luminosity function to MUV ∼ −3 during reionization.
Convex-Rod Derotation Maneuver on Lenke Type I Adolescent Idiopathic Scoliosis
Authors: Zifang Huang , Hengwei Fan , Yaolong Deng , Wenyuan Sui , Qifei Wang , Lei Cao , Li Fobao , Junlin Yang
Published: March 2017

BACKGROUND

Convex-rod derotation may have potential advantages for adolescent idiopathic scoliosis (AIS) correction; however, study of this technique has been limited.

OBJECTIVE

To compare the radiographic outcomes of Lenke type I AIS patients treated by the convex- or concave-rod derotation maneuvers.

METHODS

A retrospective study was designed to compare 2 cohorts, including 81 Lenke type I AIS patients treated with convex-rod derotation (n = 38) or concave-rod derotation (n = 43), between July 2008 and September 2012. All patients had complete clinical records and radiographic data, which were collected and compared between groups.

RESULTS

In comparing 9 radiographic parameters, significant differences were found in the incidence of screw misplacement, the postoperative main-curve angle, and the corrective rate between groups. The major-curve angles in both the convex- and the concave-rod derotation groups were corrected from 54.0° ± 10.6° and 53.0° ± 11.1° preoperatively, to 8.5° ± 6.9° and 12.9° ± 6.8° postoperatively, with corrective rates of 85.3% and 76.0%, respectively (P = .001). Final T5-T12 kyphosis and appropriate coronal-to-sagittal balance were achieved in both groups. The incidence of screw misplacement in the convex and concave sides of all patients was 1.8% and 3.7%, respectively (P = .047), and 1.8% and 3.6%, respectively, in the convex- and the concave-rod derotation groups (P = .044).

CONCLUSION

Compared with concave-rod derotation, convex-rod derotation can potentially improve the major-curve corrective rate and tends to reduce the risk of pedicle breach in Lenke type I AIS patients.
Self-assembled semiconductor quantum dots decorating the facets of GaAs nanowire for single-photon emission
Authors: Yu Ying , Zha Guo-Wei , Shang Xiang-Jun , Yang Shuang , Sun Ban-Quan , Ni Hai-Qiao , Niu Zhi-Chuan
Published: March 2017

In this chapter, we discuss the epitaxial growth of self-assembled quantum dots (QDs) in GaAs nanowires (NWs) and the characteristics of their single-photon emissions. We demonstrate Ga droplet-induced gold-free vapor-liquid-solid growth of hexagonal GaAs/AlGaAs core–shell NWs, branched GaAs NWs and tailored nanostructured morphologies on the NW facets. Particularly, we show two new types of QD-in-NW systems: one is a single InAs QD formed at the corner of a branched GaAs NW, and the other is a single GaAs QD formed on the NW facet. Sharp excitonic emission spectral lines are observed with vanishing two-photon emission probability. Furthermore, a single GaAs QD is achieved at the site of a single AlGaAs quantum ring (QR) on the NW facet. In addition, these NW-based single QDs are in-situ probed and integrated with single-mode optical fibers to achieve all-fiber-output single-photon sources for potential application in quantum integrated networks.
Human Coronavirus-HKU1 Infection Among Adults in Cleveland, Ohio
Authors: Kanwar Anubhav , Selvaraju Suresh , Esper Frank
Published: March 2017

Background

Human coronaviruses (CoV) have been long recognized as a common cause of respiratory tract disease including severe respiratory tract illness. Coronavirus-HKU1 has been described predominantly among children less than 5 years of age in the United States with few studies characterizing the disease spectrum among adults.

Methods

Nasopharyngeal specimens of patients with respiratory symptoms were analyzed for CoV-HKU1 by NxTAG Respiratory Pathogen Panel multiplex assay from February 7, 2016 to April 30, 2016. Epidemiologic, clinical, and laboratory data were collected on adults (patients >18 years) whose samples screened positive.

Results

Of 832 adult respiratory specimens screened, 13 (1.6%) cases of CoV-HKU1 were identified. Adults age ranged between 23 and 75 years and 6 (46%) were males. All of whom had 1 or more respiratory symptoms, and 5 (38%) also reported 1 or more gastrointestinal symptoms. Eleven (85%) reported history of smoking and 5 (38%) used inhaled steroids. Seven (54%) required hospitalization, 5 (71%) of these needed supplemental oxygen, and 2 (29%) were admitted to intensive care. Median length of hospitalization was 5 days. Eight (62%) received antibiotics despite identification of CoV-HKU1. Infectious work-up in 1 patient who died did not reveal any other pathogen. In 2 (15%) CoV-HKU1-positive adults, the only viral coinfection detected was influenza A.

Conclusions

Coronavirus-HKU1 accounted for 1.6% of adult respiratory infections and should be considered in differential diagnosis of severe respiratory illnesses among adults.
A Report of Adult Human Adenovirus Infections in a Tertiary Hospital
Authors: Kalimuddin Shirin , Chan Yvonne F. Z. , Wu Ian Q. , Tan Qiao Li , Murthee Kavitha G. , Tan Ban Hock , Oon Lynette L. E. , Yang Yong , Lin Raymond T. P. , Joseph Udayan , Sessions October M. , Smith Gavin J. D. , Ooi Eng Eong , Low Jenny G. H.
Published: March 2017

We describe a review of human adenovirus (HAdV) infections occurring among adults in a tertiary hospital in Singapore from February to May 2013. A similar increase in cases was observed among children and military personnel during the same time period. The majority of isolates were identified as HAdV-7, likely an emerging pathogen in Asia.
Evaluation of a Novel Alcohol-Based Surface Disinfectant for Disinfection of Hard and Soft Surfaces in Healthcare Facilities
Authors: Alhmidi Heba , Koganti Sreelatha , Cadnum Jennifer L. , Rai Herleen , Jencson Annette L. , Donskey Curtis J.
Published: March 2017

We examined the efficacy of a new 1-step cleaner and disinfectant containing 30% ethanol that is applied as a spray. The product rapidly reduced vegetative bacterial pathogens on carriers and on hard and soft surfaces in healthcare settings, but it did not stain clothing.
Curative Effects for B-Cell Lymphoma Accomplished by Direct-Acting Antiviral Agents of Hepatitis C
Authors: Hattori Nobuhiro , Ikeda Hiroki , Nakano Hiroyasu , Matsumoto Nobuyuki , Watanabe Tsunamasa , Shigefuku Ryuta , Noguchi Yohei , Matsunaga Kotaro , Sakai Hirotaka , Okuse Chiaki , Yamamoto Hiroyuki , Miura Ikuo , Suzuki Michihiro , Itoh Fumio
Published: March 2017

Hepatitis C virus (HCV) is a hepatotropic and lymphotropic virus with the capabilities of tumorigenesis. We present an HCV-infected patient affected with B-cell lymphomas after suffering from hepatocellular carcinoma. The patient exhibited curative effects for lymphomas after treatment with sofosbuvir and ledipasvir, which is shown clearly with a positron emission tomography scanner.
Pyogenic Arthritis of the Fingers and the Wrist: Can We Shorten Antimicrobial Treatment Duration?
Authors: Meier Rahel , Wirth Thomas , Hahn Frederik , Vögelin Esther , Sendi Parham
Published: March 2017

Background

Pyogenic arthritis of the small joints of the hand and wrist is a known but poorly described entity. The objective of this work was to characterize the clinical presentation, antimicrobial treatment, and surgical interventions of native small joint arthritis (SJA) treated in our tertiary center.

Methods

According to predefined variables, medical records of adult patients with SJA treated in a Swiss university hospital between 2005 and 2013 were retrospectively analyzed.

Results

The median age of 97 patients (101 joints) was 52 years (interquartile range [IQR], 38–68 years); 52% had no comorbidity. Small joint arthritis of the second and third fingers accounted for 53% of infections, with metacarpal-phalangeal and proximal interphalangeal joints most commonly involved. Of 86 (89%) episodes with an exogenous source, 63 (65%) followed a trauma. The most commonly isolated microorganism was Staphylococcus aureus (38%), followed by β-hemolytic streptococci (13%) and Pasteurella spp (11%). Eighty-seven episodes (89 joints) in patients with follow-up examinations were included in treatment and outcome analyses. Up to 2 surgical interventions were required to cure infection in 74 (83%) joints. Median antimicrobial treatment duration was 14 days (IQR, 12–28 days), with amoxicillin/clavulanate administered in 74 (85%) episodes. At follow up, cure of infection was noted in all episodes and good functional outcome in 79% of episodes.

Conclusions

Small joint arthritis shows considerable differences from clinical patterns reported for larger joints. In our series, the outcome was good with no more than 2 surgical interventions and median treatment duration of 14 days in 79% of episodes.
Patient Comprehension and Compliance Survey to Assess Postoperative Pain Regimens in the Orthopaedic Trauma Population
Authors: Gangavalli Anup K. , Malige Ajith , Rehman Saqib , Nwachuku Chinenye O.
Published: March 2017

Objective:

This study aims to determine the groups of patients who are at risk for noncompliance and misunderstanding of their pain regimen.

Design:

Survey-based cohort study.

Setting:

Suburban Level-I trauma center.

Patients/Participants:

A total of 171 patients between the ages of 18–89 years who underwent surgical fixation of fractures involving the pelvis, long bones, or periarticular regions of the knee, ankle, elbow, and wrist.

Main Outcome Measurements:

Patients who cannot accurately reproduce their prescribed pain medication list and patients who modify this pain medication regimen were analyzed by age, employment status, income level, education level, time between surgery and follow-up, and whether pain interfered with activities of daily living.

Results:

Overall, 147 patients completed the survey. Seventy percent (n = 114) of patients could not accurately reproduce their pain medication regimen, regardless of age, employment status, income level, education level, time between surgery and follow-up, and whether pain interfered with activities of daily living. Patients (61.2%; n = 90), regardless of the 6 aforementioned demographic factors, also admitted to modifying their pain medication regimen with non-prescribed medications, with 55.8% (n = 82) of patients adding over-the-counter medications to surgeon-prescribed narcotic medications.

Conclusions:

Misunderstanding and noncompliance of surgeon-prescribed pain regimens are prevalent across all patient demographics. Knowledge of the potential effects these augmentative medications can have on fracture healing and any drug-drug interactions that may arise is an important aspect of patient postoperative care. Surgeons must be wary of these trends and screen for any unintended side effects a patient's pain regimen may have.

Level of Evidence:

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Social to Moderate Alcohol Consumption Provides a Protective Effect for Functional Outcomes After Fixation of Orthopaedic Fractures
Authors: Saleh Hesham , Driesman Adam , Fisher Nina , Leucht Philipp , Konda Sanjit , Egol Kenneth
Published: March 2017

Objectives:

To identify the association between social and moderate alcohol consumption and functional outcomes after surgical management of orthopaedic fractures.

Design:

Prospective cohort study.

Setting:

Level 1 trauma center.

Patients/Participants:

Seven hundred eighty-four patients who were operatively treated for an isolated orthopaedic fracture were prospectively followed. Patients were categorized into groups according to self-reported drinking frequencies based on NIAAA guidelines.

Main Outcome Measurements:

SMFA scores at baseline, 3, 6, and 12 months postoperatively; postoperative complications; and subsequent operations.

Results:

There were 367 (46.8%) abstinent, 327 (41.7%) social, 52 (6.6%) moderate, and 38 (4.8%) heavy drinkers. Mean SMFA scores of social and moderate drinkers were significantly lower than those of abstinent patients at 3-, 6-, and 12-month follow-ups, denoting better functional outcomes (social: 24.3 vs. 30.5, P = 0.001; 14.8 vs. 21.5, P < 0.005; and 10.1 vs. 18.8, P < 0.005); (moderate: 18.3 vs. 30.5, P = 0.001; 9.7 vs. 21.5, P = 0.001; and 5.4 vs. 18.8, P < 0.005). Multiple linear regression revealed that social drinking and baseline SMFA scores were the only statistically significant independent predictors of lower SMFA scores at 12 months after surgery.

Conclusions:

Social to moderate drinking may have a protective effect on functional outcomes at 3, 6, and 12 months after surgery. Social drinking may also have a protective effect on postoperative complications and reoperation rates. Further studies should be performed to fully appreciate the clinical effect of social and moderate drinking after operative treatment of orthopaedic fractures.

Level of Evidence:

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Does Concurrent Tibial Intramedullary Nailing and Fibular Fixation Increase Rates of Tibial Nonunion? A Matched Cohort Study
Authors: Githens Michael , Haller Justin , Agel Julie , Firoozabadi Reza
Published: March 2017

Objectives:

To determine if there is a difference in rates of tibial nonunion in patients undergoing tibial intramedullary (IM) nailing and fibular fixation as compared to a matched cohort undergoing tibial IM nailing alone.

Design:

Retrospective matched cohort study.

Setting:

Single Level 1 academic trauma center.

Patients:

Consecutive patients 18 years and older with a tibia and fibula fracture treated with tibial IM nailing and fibular fixation who were determined radiographically and clinically healed or had a minimum 1-year follow-up were included. A matched cohort who underwent tibial IM nailing without fibular fixation was used for comparison.

Intervention:

Fibular fixation at the time of tibial IM nailing.

Main Outcome Measurement:

Tibial nonunion, defined as a persistently symptomatic fracture with no radiographic progression toward healing at 9 months on consecutive radiographs over a 2-month period.

Results:

One hundred sixty six patients met inclusion criteria for the intervention group. Mean follow-up was 21 months. There was a 12% rate of tibial nonunion. In a matched cohort of 174 patients without fibular fixation there was no significant difference in patient demographics, injury characteristics, infection rates, time to union, postoperative complications, or rates of tibial nonunion. The rate of nonunion in both groups was significantly higher in patients with high energy mechanisms, open fractures, and postoperative infections.

Conclusion:

Fibular fixation did not impact rates of tibial nonunion. The rate of tibial nonunion in both cohorts is comparable with published rates of tibial nonunion after IM nailing without fibular fixation. Open fractures, high energy mechanism, and postoperative infection are significantly associated with tibial nonunion.

Level of Evidence:

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Tibial Eminence Involvement With Tibial Plateau Fracture Predicts Slower Recovery and Worse Postoperative Range of Knee Motion
Authors: Konda Sanjit R. , Driesman Adam , Manoli Arthur , Davidovitch Roy I. , Egol Kenneth A.
Published: March 2017

Objectives:

To examine 1-year functional and clinical outcomes in patients with tibial plateau fractures with tibial eminence involvement.

Design:

Retrospective analysis of prospectively collected data.

Setting:

Academic Medical Center.

Patients/Participants:

All patients who presented with a tibial plateau fracture (Orthopaedic Trauma Association (OTA) 41-B and 41-C).

Intervention:

Patients were divided into fractures with a tibial eminence component (+TE) and those without (−TE) cohorts. All patients underwent similar surgical approaches and fixation techniques for fractures. No tibial eminence fractures received fixation specifically.

Main Outcome Measurements:

Short musculoskeletal functional assessment (SMFA), pain (Visual Analogue Scale), and knee range-of-motion (ROM) were evaluated at 3, 6, and 12 months postoperatively and compared between cohorts.

Results:

Two hundred ninety-three patients were included for review. Patients with OTA 41-C fractures were more likely to have an associated TE compared with 41-B fractures (63% vs. 28%, P < 0.01). At 3 months postoperatively, the +TE cohort was noted to have worse knee ROM (75.16 ± 51 vs. 86.82 ± 53 degree, P = 0.06). At 6 months, total SMFA and knee ROM was significantly worse in the +TE cohort (29 ± 17 vs. 21 ± 18, P ≤ 0.01; 115.6 ± 20 vs. 124.1 ± 15, P = 0.01). By 12 months postoperatively, only knee ROM remained significantly worse in the +TE cohort (118.7 ± 15 vs. 126.9 ± 13, P < 0.01). Multivariate analysis revealed that tibial eminence involvement was a significant predictor of ROM at 6 and 12 months and SFMA at 6 months. Body mass index was found to be a significant predictor of ROM and age was a significant predictor of total SMFA at all time points.

Conclusion:

Knee ROM remains worse throughout the postoperative period in the +TE cohort. Functional outcome improves less rapidly in the +TE cohort but achieves similar results by 1 year.

Level of Evidence:

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Patterns of Opioid Prescribing for an Orthopaedic Trauma Population
Authors: Ruder John , Wally Meghan K. , Oliverio McKell , Seymour Rachel B. , Hsu Joseph R. ,   the PRIMUM Group
Published: March 2017

Objectives:

To determine opioid-prescribing practices to the orthopaedic trauma (OT) population at one Level I trauma center.

Design:

A retrospective study of discharge prescriptions for adult patients with OT. Prescription details, injury burden, and patient demographics were abstracted for patients from initial injury through a 2-month follow-up.

Setting:

Level I trauma center.

Patients/Participants:

Adult patients with OT admitted over a 30-day period (n = 110).

Intervention:

All discharge and follow-up opioid prescriptions were recorded.

Main Outcome Measurements:

Morphine milligram equivalents (MMEs) per day, number of opioid prescriptions, type/dose of medication prescribed.

Results:

One hundred thirty-five discharge prescriptions were written for 110 patients with orthopaedic injuries during the review period. All patients received opioids at the time of discharge. The MMEs prescribed at the time of discharge was 114 mg (54–300 mg) for a mean of 7.21 days (2–36.7 days). Although patients with preinjury risk factors were prescribed discharge opioids for a similar duration (7.00 days vs. 7.30 days, P = 0.81) than those without risk factors, they were prescribed significantly more MMEs than those without (130 vs. 108, P < 0.05) and were more likely to receive extended-release and long-acting opioids than those without (42.11% vs. 21.98%).

Conclusions:

Pain management after OT continues to be opioid-centric despite involving a population at risk. Further focus on prescriber and patient education, risk evaluation with mitigation, guideline development, and comprehensive pain management strategies are warranted in the OT population.

Level of Evidence:

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Tranexamic Acid Safely Reduced Blood Loss in Hemi- and Total Hip Arthroplasty for Acute Femoral Neck Fracture: A Randomized Clinical Trial
Authors: Watts Chad D. , Houdek Matthew T. , Sems S. Andrew , Cross William W. , Pagnano Mark W.
Published: March 2017

Objectives:

We aimed to determine whether (1) tranexamic acid (TXA) reduces the incidence of transfusion (2) TXA reduces the calculated blood loss, and (3) there are any observable differences in 30- and 90-day complications with TXA administration during arthroplasty for femoral neck fracture (FNF).

Design:

Prospective, double-blinded, randomized controlled trial.

Setting:

Level 1 Academic Trauma Center.

Patients/Participants:

One hundred thirty-eight patients who presented with a low-energy, isolated, FNF (AO 31B) treated with either hemi- or total hip arthroplasty within 72 hours of injury were randomized to either the TXA group (69 patients) or placebo group (69 patients).

Intervention:

In the TXA group, patients received 2 doses of 15 mg/kg intravenous TXA dissolved in 100 mL of saline, each administered over 10 minutes; 1 dose just before incision, and the second at wound closure. In the placebo group, 100 mL of saline solution was administered in a similar fashion. Perioperative care was otherwise standardized including conservative transfusion criteria.

Main Outcome Measurements:

Our primary outcome was to determine the proportion of patients who underwent blood transfusion during hospitalization. Secondary outcomes were calculated blood loss, number of units transfused during hospitalization, and incidence of adverse events at 30 and 90 days including thromboembolic event, wound complications, reoperation, hospital readmission, and all-cause mortality.

Results:

TXA reduced mean incidence of transfusion by 305 mL (P = 0.0005). There was a trend toward decreased transfusion rate in the TXA group (17% vs. 26%, P = 0.22). TXA was safe with no differences in adverse events at 30 and 90 days.

Conclusions:

This randomized clinical trial found that TXA administration safely reduced blood loss with a tendency for decreased transfusion rate and total blood product consumption for patients undergoing hip arthroplasty for acute FNF. More studies are needed to further ascertain the role of TXA in the management of patients with FNF.

Level of Evidence:

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.
Hexapod Frame Stacked Transport for Tibial Infected Nonunions With Bone Loss: Analysis of Use of Adjunctive Stability
Authors: Napora Joshua K. , Weinberg Douglas S. , Eagle Blake A. , Kaufman Bram R. , Sontich John K.
Published: March 2017

Objectives:

The stacked hexapod bone transport technique is an effective treatment for infected tibial nonunions with bone loss. The purpose of this study was to evaluate the patients' risk factors and timing for requiring adjunctive stabilization.

Design:

Retrospective cohort study.

Setting:

Level 1 trauma center.

Patients/Participants:

Seventy-five patients with infected posttraumatic nonunions of the tibia.

Intervention:

Resection of nonunion with application of stacked hexapod frame for bone transport.

Main Outcome Measurements:

Parameters measured included age, sex, diabetes, smoking, use of a free flap, bone defect size, length in frame, external fixation index, and direction of lengthening. Outcomes recorded: removal of frame, below knee amputation, or adjunctive stability. Further analysis evaluated location of nonunion, timing of adjunctive stabilization, and type of fixation.

Results:

The average patient age was 45.7 ± 12.5 years, 76% patients were men, 11% were diabetic, and 44% were smokers. Forty two percent had soft tissue defects that required a free flap. Thirty-eight patients had removal of frame, whereas 36 patients required adjunctive stability of the hexapod frame. Patient receiving adjunctive stabilization had a longer length of time in the hexapod frame (P = 0.026) and were more likely to require a free flap (P = 0.053). Ninety-three percent docking site nonunions occurred after the removal of the frame (P = 0.032); whereas 79% regenerate nonunions occurred before the hexapod frame was removed (P = 0.029).

Conclusions:

The use of a hexapod frame for the infected tibial nonunions with bone loss is an effective method for achieving union and eradicating infection in a difficult orthopaedic patient population. Use of adjunctive stabilization is a reasonable technique to address delayed regenerate and docking site nonunions.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Radiographic Review of Helical Blade Versus Lag Screw Fixation for Cephalomedullary Nailing of Low-Energy Peritrochanteric Femur Fractures: There is a Difference in Cutout
Authors: Stern Lorraine C. , Gorczyca John T. , Kates Stephen , Ketz John , Soles Gillian , Humphrey Catherine A.
Published: March 2017

Objectives:

To compare the rate of cutout of helical blades and lag screws in low-energy peritrochanteric femur fractures treated with a cephalomedullary nail (CMN).

Design:

Retrospective review.

Setting:

Academic medical center.

Patients:

Overall, this study included 362 patients with an average age of 83 year old, a majority of whom were women, and had sustained a low-energy peritrochanteric femur fracture treated with a CMN. All patients had at least 3 months of clinical and radiographic follow, with an average follow-up of 11 months and a range of 3–88 months follow-up.

Intervention:

Cephalomedullary nailing with the use of a helical blade or single lag screw for proximal fixation.

Main Outcome Measurements:

Cutout of the helical blade or lag screw.

Results:

Twenty-two cutouts occurred, 14 (15.1%) of 93 patients with helical blades and 8 (3.0%) of 269 patients with lag screws. Cutout with the helical blade was significantly more frequent than with the lag screw (P = 0.0001). The average tip–apex distance (TAD) was significantly greater for those patients who experienced cutout both for the helical blades (23.5 vs. 19.7 mm; P = 0.0194) and lag screws (24.5 vs. 20.0 mm; P = 0.0197). An absolute TAD predictive of cutout could not be determined.

Conclusions:

When the helical blade was used, implant cutout occurred at a significantly higher rate compared with lag screw fixation. There was not a threshold TAD that was predictive of cutout for either implant.

Level of Evidence:

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.