bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermodynamics of inversion-domain boundaries in aluminum nitride: Interplay between interface energy and electric dipole potential energy
Authors: Zhang J. Y. , Xie Y. P. , Guo H. B. , Chen Y. G.
Published: May 2018

Aluminum nitride (AlN) has a polar crystal structure that is susceptible to electric dipolar interactions. The inversion domains in AlN, similar to those in GaN and other wurtzite-structure materials, decrease the energy associated with the electric dipolar interactions at the expense of inversion-domain boundaries, whose interface energy has not been quantified. We study the atomic structures of six different inversion-domain boundaries in AlN, and compare their interface energies from density functional theory calculations. The low-energy interfaces have atomic structures with similar bonding geometry as those in the bulk phase, while the high-energy interfaces contain N-N wrong bonds. We calculate the formation energy of an inversion domain using the interface energy and dipoles' electric-field energy, and find that the distribution of the inversion domains is an important parameter for the microstructures of AlN films. Using this thermodynamic model, it is possible to control the polarity and microstructure of AlN films by tuning the distribution of an inversion-domain nucleus and by selecting the low-energy synthesis methods.
Theoretical analysis on lower band cascade as a mechanism for multiband chorus in the Earth’s magnetosphere
Authors: Gao Xinliang , Lu Quanming , Wang Shaojie , Wang Shui
Published: May 2018

Whistler-mode waves play a crucial role in controlling electron dynamics in the Earth’s Van Allen radiation belt, which is increasingly important for spacecraft safety. Using THEMIS waveform data, Gao et al. [X. L. Gao, Q. Lu, J. Bortnik, W. Li, L. Chen, and S. Wang, Geophys. Res. Lett., 43, 2343-2350, 2016] have reported two multiband chorus events, wherein upper-band chorus appears at harmonics of lower-band chorus. They proposed that upper-band harmonic waves are excited through the nonlinear coupling between the electromagnetic and electrostatic components of lower-band chorus, a second-order effect called “lower band cascade”. However, the theoretical explanation of lower band cascade was not thoroughly explained in the earlier work. In this paper, based on a cold plasma assumption, we have obtained the explicit nonlinear driven force of lower band cascade through a full nonlinear theoretical analysis, which includes both the ponderomotive force and coupling between electrostatic and electromagnetic components of the pump whistler wave. Moreover, we discover the existence of an efficient energy-transfer (E-t) channel from lower-band to upper-band whistler-mode waves during lower band cascade for the first time, which is also confirmed by PIC simulations. For lower-band whistler-mode waves with a small wave normal angle (WNA), the E-t channel is detected when the driven upper-band wave nearly satisfies the linear dispersion relation of whistler mode. While, for lower-band waves with a large WNA, the E-t channel is found when the lower-band wave is close to its resonant frequency, and the driven upper-band wave becomes quasi-electrostatic. Through this efficient channel, the harmonic upper band of whistler waves is generated through energy cascade from the lower band, and the two-band spectral structure of whistler waves is then formed. Both two types of banded whistler-mode spectrum have also been successfully reproduced by PIC simulations.
Synthesis and electronic properties of Fe2TiO5 epitaxial thin films
Authors: Osada Motoki , Nishio Kazunori , Hwang Harold Y. , Hikita Yasuyuki
Published: May 2018

We investigate the growth phase diagram of pseudobrookite Fe2TiO5 epitaxial thin films on LaAlO3 (001) substrates using pulsed laser deposition. Control of the oxygen partial pressure and temperature during deposition enabled selective stabilization of (100)- and (230)-oriented films. In this regime, we find an optical gap of 2.1 eV and room temperature resistivity in the range of 20–80 Ω cm, which are significantly lower than α-Fe2O3, making Fe2TiO5 potentially an ideal inexpensive visible-light harvesting semiconductor. These results provide a basis to incorporate Fe2TiO5 in oxide heterostructures for photocatalytic and photoelectrochemical applications.
Demodulation method for tilted fiber Bragg grating refractometer with high sensitivity
Authors: Pham Xuantung , Si Jinhai , Chen Tao , Wang Ruize , Yan Lihe , Cao Houjun , Hou Xun
Published: May 2018

In this paper, we propose a demodulation method for refractive index (RI) sensing with tilted fiber Bragg gratings (TFBGs). It operates by monitoring the TFBG cladding mode resonance “cut-off wavelengths.” The idea of a “cut-off wavelength” and its determination method are introduced. The RI sensitivities of TFBGs are significantly enhanced in certain RI ranges by using our demodulation method. The temperature-induced cross sensitivity is eliminated. We also demonstrate a parallel-double-angle TFBG (PDTFBG), in which two individual TFBGs are inscribed in the fiber core in parallel using a femtosecond laser and a phase mask. The RI sensing range of the PDTFBG is significantly broader than that of a conventional single-angle TFBG. In addition, its RI sensitivity can reach 1023.1 nm/refractive index unit in the 1.4401–1.4570 RI range when our proposed demodulation method is used.
Orientational ordering of lamellar structures on closed surfaces
Authors: Pȩkalski J. , Ciach A.
Published: May 2018

Self-assembly of particles with short-range attraction and long-range repulsion interactions on a flat and on a spherical surface is compared. Molecular dynamics simulations are performed for the two systems having the same area and the density optimal for formation of stripes of particles. Structural characteristics, e.g., a cluster size distribution, a number of defects, and an orientational order parameter (OP), as well as the specific heat, are obtained for a range of temperatures. In both cases, the cluster size distribution becomes bimodal and elongated clusters appear at the temperature corresponding to the maximum of the specific heat. When the temperature decreases, orientational ordering of the stripes takes place and the number of particles per cluster or stripe increases in both cases. However, only on the flat surface, the specific heat has another maximum at the temperature corresponding to a rapid change of the OP. On the sphere, the crossover between the isotropic and anisotropic structures occur in a much broader temperature interval; the orientational order is weaker and occurs at significantly lower temperature. At low temperature, the stripes on the sphere form spirals and the defects resemble defects in the nematic phase of rods adsorbed at a sphere.
Spectrum study on unsteadiness of shock wave–vortex ring interaction
Authors: Dong Xiangrui , Yan Yonghua , Yang Yong , Dong Gang , Liu Chaoqun
Published: May 2018

Shock oscillation with low-frequency unsteadiness commonly occurs in supersonic flows and is a top priority for the control of flow separation caused by shock wave and boundary layer interaction. In this paper, the interaction of the shock caused by the compression ramp and the vortex rings generated by a micro-vortex generator (MVG) in a supersonic flow at Ma = 2.5 is simulated by the implicit large eddy simulation method. The analysis of observation and the frequency of both the vortex ring motion and the shock oscillation is carried out. The results show that the shock produced by a compression ramp flow at Ma = 2.5 has a dominant non-dimensional low frequency, which is around St = 0.002, while the vortex rings behind the MVG have a dominant high frequency which is around St = 0.038. The dominant low frequency of the shock, which is harmful, can be removed or weakened through the shock-vortex ring interaction by the vortex rings which generate high frequency fluctuations. In the shock and vortex ring interaction region, a dominant high frequency St = 0.037–0.038 has been detected rather than the low frequency St = 0.002, which indicates that the vortex ring is stiff enough to break or weaken the shock. This analysis could provide an effective tool to remove or weaken the low frequency pressure fluctuation below 500 Hz, which has a negative effect on the flight vehicle structures and the environmental protection, through the high frequency vortex generation.
Contact resistance change memory using N-doped Cr2Ge2Te6 phase-change material showing non-bulk resistance change
Authors: Shuang Y. , Sutou Y. , Hatayama S. , Shindo S. , Song Y. H. , Ando D. , Koike J.
Published: May 2018

Phase-change random access memory (PCRAM) is enabled by a large resistance contrast between amorphous and crystalline phases upon reversible switching between the two states. Thus, great efforts have been devoted to identifying potential phase-change materials (PCMs) with large electrical contrast to realize a more accurate reading operation. In contrast, although the truly dominant resistance in a scaled PCRAM cell is contact resistance, less attention has been paid toward the investigation of the contact property between PCMs and electrode metals. This study aims to propose a non-bulk-resistance-dominant PCRAM whose resistance is modulated only by contact. The contact-resistance-dominated PCM exploited here is N-doped Cr2Ge2Te6 (NCrGT), which exhibits almost no electrical resistivity difference between the two phases but exhibits a typical switching behavior involving a three-order-of-magnitude SET/RESET resistance ratio owing to its large contact resistance contrast. The conduction mechanism was discussed on the basis of current–voltage characteristics of the interface between the NCrGT and the W electrode.
Unconventional superconductivity discovered in graphene bilayers
Authors: Miller Johanna L.
Published: May 2018

When two carbon sheets are misaligned by a mere degree, striking changes result.
Domesticating physics
Authors: Behrman Joanna
Published: May 2018

A historical snapshot of physics education for women illuminates how housework was used to draw women into physics courses—and how science was used to sell home appliances.
Phylogeny, species delimitation and revision of Pleioluma (Sapotaceae) in New Caledonia, a frequently gynodioecious genus
Authors: Swenson Ulf , Nylander Johan A. A. , Munzinger Jérôme
Published: May 2018

Pleioluma (Baill.) Baehni (Sapotaceae) circumscribes some 40 medium-sized trees and shrubs, many gynodioecious, in Australia, Malesia and New Caledonia. Systematics of the group is unclear and delimitations of species are notoriously difficult. We explore species boundaries in New Caledonia by multiple accessions of ‘species’, molecules and morphology in a Bayesian framework. The molecular phylogenetic signal is weak, but morphology provides enough information to support groups, species and recognition of one cryptic species. Pleioluma is then revised for New Caledonia, a genus distinguished by areolate higher leaf venation, sepals being pubescent on both surfaces, stamens inserted in or below the middle of the corolla tube, presence of staminodes, foliaceous cotyledons and endosperm. Seventeen endemic species are recognised with descriptions, recognition notes, distributions, etymologies and conservation assessments. Six species are described as new, of which four are assigned IUCN preliminary status as Critically Endangered and in urgent need of protection (Pleioluma acutifolia Swenson & Munzinger, P. belepensis Swenson & Munzinger, P. butinii Swenson & Munzinger and P. tchingouensis Swenson & Munzinger). The new species, P. dioica Swenson & Munzinger and P. tenuipedicellata Swenson & Munzinger are respectively assessed as Data Deficient and Vulnerable. The micro-endemic species P. vieillardii (Baill.) Swenson & Munzinger, confined to the Koniambo massif, is also critically endangered and needs urgent conservation management.
Walking the tightrope
Authors: de Pedro Ricoy Raquel , Howard Rosaleen , Andrade Ciudad Luis
Published: May 2018

The passing of the Prior Consultation Act (2011) was a turning point in Peru’s history: it enshrined the right of indigenous peoples to be consulted prior to the State’s adopting a measure that affects them and to use their own languages during the consultation, which makes interpreting essential. This article focuses on the complexities of the interpreters’ role and how the beneficiaries of their work perceive it. It reveals that the interpreters’ performance is determined by two circumstances: first, it straddles public service and business interpreting; and second, the fact that the interpreters are trained and employed by the State creates tensions in the communication between the latter and the indigenous peoples. The socio-political context and the initiatives designed to ensure compliance with the law will provide a background to our findings. These derive from observation, interviews and meetings with institutional actors and interpreters, and are illustrated by a case study.
Hrushevsky's Constitutional Project of 1905∗
Authors: Prymak Thomas M.
Published: May 2018

Mykhailo Hrushevsky (1866–1934) was one of the most important Ukrainian public figures of modern times. In the realm of scholarship, he was the greatest of Ukrainian historians whose ten-volume History of Ukraine-Rus' charted the saga of the Ukrainian people from antiquity to modern times. He was a prolific writer and essayist whose personal bibliography lists over 2,000 titles. He was also the principal organizer of an unofficial Ukrainian Academy of Sciences in Austrian Galicia—the Shevchenko Scientific Society—and towards the end of his life became the single most important cultural figure in the Ukrainian Soviet Socialist Republic.
The Problem of Bilingualism: A View Without Rose-Tinted Glasses∗
Authors: Mint Maté , Mairs Tanya E.
Published: May 2018

A Commentary on Basic Terminology

Bilingualism is the ability of an individual to use two languages to an equal or near equal degree. A completely bilingual person can switch from one language to another instantaneously.
The role of cytochrome P450 enzymes in carcinogen activation and detoxication: an in vivo–in vitro paradox
Authors: Reed Lindsay , Arlt Volker M , Phillips David H
Published: May 2018

Cytochrome P450 enzyme systems have been widely used in vitro to determine the pathways of activation of procarcinogens, but paradoxically, these same enzymes can play a more predominant role in carcinogen detoxification in vivo.
CNF1-like deamidase domains: common Lego bricks among cancer-promoting immunomodulatory bacterial virulence factors
Authors: Ho Mengfei , Mettouchi Amel , Wilson Brenda A , Lemichez Emmanuel
Published: May 2018

Alterations of the cellular proteome over time due to spontaneous or toxin-mediated enzymatic deamidation of glutamine (Gln) and asparagine (Asn) residues contribute to bacterial infection and might represent a source of aging-related diseases. Here, we put into perspective what is known about the mode of action of the CNF1 toxin from pathogenic Escherichia coli, a paradigm of bacterial deamidases that activate Rho GTPases, to illustrate the importance of determining whether exposure to these factors are risk factors in the etiology age-related diseases, such as cancer. In particular, through in silico analysis of the distribution of the CNF1-like deamidase active site Gly-Cys-(Xaa)n-His sequence motif in bacterial genomes, we unveil the wide distribution of the super-family of CNF-like toxins and CNF-like deamidase domains among members of the Enterobacteriacae and in association with a large variety of toxin delivery systems. We extent our discussion with recent findings concerning cellular systems that control activated Rac1 GTPase stability and provide protection against cancer. These findings point to the urgency for developing holistic approaches toward personalized medicine that include monitoring for asymptomatic carriage of pathogenic toxin-producing bacteria and that ultimately might lead to improved public health and increased lifespans.
An efficient algorithm for simulating ensembles of parameterized flow problems
Authors: Gunzburger Max , Jiang Nan , Wang Zhu
Published: May 2018

Many applications of computational fluid dynamics require multiple simulations of a flow under different input conditions. In this paper, a numerical algorithm is developed to efficiently determine a set of such simulations in which the individually independent members of the set are subject to different viscosity coefficients, initial conditions and/or body forces. The proposed scheme, when applied to the flow ensemble, needs to solve a single linear system with multiple right-hand sides, and thus is computationally more efficient than solving for all the simulations separately. We show that the scheme is nonlinearly and long-term stable under certain conditions on the time-step size and a parameter deviation ratio. A rigorous numerical error estimate shows the scheme is of first-order accuracy in time and optimally accurate in space. Several numerical experiments are presented to illustrate the theoretical results.
An orthotopic glioblastoma animal model suitable for high-throughput screenings
Authors: Pudelko Linda , Edwards Steven , Balan Mirela , Nyqvist Daniel , Al-Saadi Jonathan , Dittmer Johannes , Almlöf Ingrid , Helleday Thomas , Bräutigam Lars
Published: May 2018

Background

Glioblastoma (GBM) is an aggressive form of brain cancer with poor prognosis. Although murine animal models have given valuable insights into the GBM disease biology, they cannot be used in high-throughput screens to identify and profile novel therapies. The only vertebrate model suitable for large-scale screens, the zebrafish, has proven to faithfully recapitulate biology and pathology of human malignancies, and clinically relevant orthotopic zebrafish models have been developed. However, currently available GBM orthotopic zebrafish models do not support high-throughput drug discovery screens.

Methods

We transplanted both GBM cell lines as well as patient-derived material into zebrafish blastulas. We followed the behavior of the transplants with time-lapse microscopy and real-time in vivo light-sheet microscopy.

Results

We found that GBM material transplanted into zebrafish blastomeres robustly migrated into the developing nervous system, establishing an orthotopic intracranial tumor already 24 hours after transplantation. Detailed analysis revealed that our model faithfully recapitulates the human disease.

Conclusion

We have developed a robust, fast, and automatable transplantation assay to establish orthotopic GBM tumors in zebrafish. In contrast to currently available orthotopic zebrafish models, our approach does not require technically challenging intracranial transplantation of single embryos. Our improved zebrafish model enables transplantation of thousands of embryos per hour, thus providing an orthotopic vertebrate GBM model for direct application in drug discovery screens.
The Impact of Different Intraoperative Fluid Administration Strategies on Postoperative Extubation Following Multilevel Thoracic and Lumbar Spine Surgery: A Propensity Score Matched Analysis
Authors: Ramchandran Subaraman , Day Louis M , Line Breton , Buckland Aaron J , Passias Peter , Protopsaltis Themistocles , Bendo John , Huncke Tessa , Errico Thomas J , Bess Shay
Published: May 2018

BACKGROUND

Patients undergoing multilevel spine surgery are at risk for delayed extubation.

OBJECTIVE

To evaluate the impact of type and volume of intraoperative fluids administered during multilevel thoracic and/or lumbar spine surgery on postoperative extubation status.

METHODS

Retrospective evaluation of medical records of patients ≥ 18 yr undergoing ≥ 4 levels of thoracic and/or lumbar spine fusions was performed. Patients were organized according to postoperative extubation status: immediate (IMEX; in OR/PACU) or delayed (DEX; outside OR/PACU). Propensity score matched (PSM) analysis was performed to compare IMEX and DEX groups. Volume, proportion, and ratios of intraoperative fluids administered were evaluated for the associated impact on extubation status.

RESULTS

A total of 246 patients (198 IMEX, 48 DEX) were included. PSM analysis demonstrated that increased administration of non-cell saver blood products (NCSB) and increased ratio of crystalloid: colloids infused were independently associated with delayed extubation. With increasing EBL, IMEX had a proportionate reduction in crystalloid infusion (R = –0.5, P < .001), while the proportion of crystalloids infused remained relatively unchanged for DEX (R = –0.27; P = .06). Twenty-six percent of patients receiving crystalloid: colloid ratio > 3:1 had DEX compared to none of those receiving crystalloid: colloid ratio ≤ 3:1 (P = .009). DEX had greater cardiac and pulmonary complications, surgical site infections and prolonged intensive care unit and hospital stay (P < .05).

CONCLUSION

PSM analysis of patients undergoing multilevel thoracic and/or lumbar spine fusion demonstrated that increased administration of crystalloid to colloid ratio is independently associated with delayed extubation. With increasing EBL, a proportionate reduction of crystalloids facilitates early extubation.
Pneumococcal Conjugate Vaccine Safety in Elderly Adults
Authors: Tseng Hung Fu , Sy Lina S , Qian Lei , Liu In-Lu A , Mercado Cheryl , Lewin Bruno , Tartof Sara Y , Nelson Jennifer , Jackson Lisa A , Daley Matthew F , Weintraub Eric , Klein Nicola P , Belongia Edward , Liles Elizabeth G , Jacobsen Steven J
Published: May 2018

Background

The 13-valent pneumococcal conjugate vaccine (PCV13) and the 23-valent pneumococcal polysaccharide vaccine (PPSV23) were both recommended to adults aged ≥65 years. The study examines adults ≥65 years for risk of adverse events (AEs) requiring medical attention following vaccination with PCV13 as compared with vaccination with PPSV23, a long-standing vaccine with a satisfactory safety profile.

Methods

The cohort study included 6 Vaccine Safety Datalink sites. The exposed person-time included follow-up time of the first PCV13 received by subjects age ≥65 years from January 1 to August 15, 2015. The comparator person-time included follow-up time after the first PPSV23 received by subjects of the same age during Janaury 1 to August 15 of each year of 2011–2015. The prespecified AEs included cardiovascular events, Bell’s palsy, Guillain-Barré syndrome, syncope, erythema multiforme, thrombocytopenia, cellulitis and infection, allergic reaction, and anaphylaxis. Inverse probability of treatment weighting–adjusted Poisson regression models was used to estimate the relative risk (RR) of each AE.

Results

A total of 313 136 doses of PCV13 and 232 591 doses of PPSV23 were included. The adjusted RRs comparing the incidence of AEs following PCV13 vs PPSV23 were all <1, except for anaphylaxis, which was insignificant with an RR of 1.32 (95% confidence interval, 0.30–5.79). Only 1 patient who received PCV13 and 4 other vaccines concomitantly was confirmed by medical chart review as having experienced anaphylaxis after vaccination.

Conclusions

These data do not support an increased rate of adverse events following PCV13 administration in elders compared with PPSV23 and should provide reassurance regarding continued use of PCV13.
Visible, Elected, but Effectively Nominal: Visibility as a Barrier Maintaining the Political Underrepresentation of Britain’s Immigrant Origin Communities
Authors: English Patrick
Published: May 2018

Ethnic minority groups have been and remain underrepresented in the British political system. However, we know little about how white immigrant origin groups—who share outgroup status based on non-native history, but differ to ethnic minority groups in terms of not having minority status—compare. Further, contemporary representational study also must concern itself with the quality, not just presence, of representation provided. This research therefore longitudinally compares the access to parliamentary roles for ethnic minority, white immigrant, and white British MPs. It finds that visibility of non-native status holds back descriptive representation—based on both appearance and non-British sounding names.
Incidence, Distribution, and Pathogenicity of Fungi Causing Root Rot in Idaho Long-Term Sugar Beet Storage Piles
Authors: Strausbaugh Carl A.
Published: May 2018

Fungal rots in sugar beet roots held in long-term storage can lead to considerable sucrose loss but the incidence and distribution of fungal rots inside sugar beet piles and pathogenicity for some species is poorly understood. Thus, Idaho sugar beet held in five outdoor and two indoor piles in 2014 and 2015 were investigated. The root surface area covered by fungal growth and discolored and healthy tissue were assessed in nine 1-m2 areas per pile using a stratified random sampling design. Pathogenicity was evaluated indoors via plug inoculation in 2015 and 2016. Botrytis cinerea covered more root surface area inside indoor piles (6 to 22%) than outdoor piles (0 to 3%) (P < 0.0001). No trends were evident for the Athelia-like sp. (0 to 15%) and Penicillium-type spp. (0 to 8%). Penicillium-type isolates comprised the following species: 60% Penicillium expansum, 34% P. cellarum, 3% P. polonicum, and 3% Talaromyces rugulosus. Trace levels (<1% of root surface) of other fungi, including Cladosporium and Fusarium spp., were evident on roots and in isolations. Based on sample location in a pile, there were no trends or differences; however, two outdoor piles (OVP1 and OVP2) had more healthy tissue (90 to 96%) than other piles (28 to 80%) (P < 0.0001). When the pathogenicity tests were analyzed by species, all were significantly different from each other (P < 0.0001), except for P. polonicum and P. expansum: B. cinerea (61 mm of rot), P. polonicum (36 mm), P. expansum (35 mm), P. cellarum (28 mm), Athelia-like sp. (21 mm), T. rugulosus (0 mm; not different from check), and noninoculated check (0 mm). The OVP1 and OVP2 piles had negligible fungal growth on roots after more than 120 days of storage under ambient conditions, which indicates that acceptable storage can be achieved over this time period through covering piles with tarps and cooling with ventilation pipe.
Instruments to Evaluate Nurse Residency Programs
Authors: Stephenson Jennifer K. , Cosme Sheryl
Published: May 2018

The purpose of this literature review was to explore evaluation instruments used by nurse residency programs to evaluate outcomes. The 15 studies found yielded 26 instruments, and all instruments were subjective, dated, and varied in how they were used. Nursing professional development practitioners should use a combination of reliable, valid, and current evaluation methods to appraise their nurse residency programs in order to demonstrate program quality and effectiveness.
Implementation of a Standardized Evaluation Tool to Improve Preceptor Confidence
Authors: Wilburn Shunda , Jones Stacey , Hamilton Bernita K.
Published: May 2018

Preceptors guide the transition of new graduate nurses into practice. Having access to evidence-based tools for evaluation of new graduate nurses promotes preceptor confidence and consistent measures of performance. The Norwegian Nurse Competence Scale was implemented across three acute care organizations for evaluation of new graduate nurse performance. After implementing a standardized process to evaluate new graduate nurses, individual summary scores ranged from 17–25 (preintervention) to 20–25 (postintervention), indicating mid to high levels of preceptor confidence.
Sports-Related Concussions in Children
Authors: O'Keefe Kraigher Allan , Beamon Bradley , Brewer Kori L. , Niceler Brock
Published: May 2018

Objectives

Patient and parent expectations can potentially influence management of care. We compared expectations in the diagnosis of concussion between patients who presented to a pediatric emergency department (ED) and those who presented to a sports medicine clinic, and if there was a difference in computed tomography (CT) scans performed.

Methods

Head-injured athletes aged 8 to 18 years presenting to a pediatric ED and a sports medicine clinic were enrolled. Both groups completed questionnaires on their understanding of concussion and expectations of care. Charts were then reviewed.

Results

Forty patients were enrolled in the study: 23 from a pediatric ED and 17 from a sports medicine clinic. Forty-one percent of athletes received a head CT in the pediatric ED versus 12% of those in the clinic population with no abnormal findings (P = 0.04). Forty-one percent of athletes and 48% of parents in the pediatric ED setting reported that a CT was “necessary” to diagnose concussion versus 18% in both groups from the clinic (P = 0.12, P = 0.07). Athletes presenting to the clinic were more likely to have been evaluated by an athletic trainer after the injury than those presenting to the pediatric ED (80% vs 23%, P = 0.004).

Conclusions

Patients and parents who presented to a pediatric ED for sports-related head injury had a trend toward higher expectations of a CT scan being necessary to diagnose concussion and did have a higher rate of CT scans performed. Education of athletes and parents engaging in organized sports may be worthwhile to assist in setting expectations in diagnosis of concussion.
Evaluation of Richmond Agitation Sedation Scale (RASS) in Mechanically Ventilated in the Emergency Department
Authors: Pop Marianne K. , Dervay Katelyn R. , Dansby Mary , Jones Carolina
Published: May 2018

The purpose of this study was to assess Richmond Agitation Sedation Scale (RASS) goal implementation in mechanically ventilated patients sedated in the emergency department (ED), compliance with RASS, and goal achievement. This study was a retrospective chart review at a large Level I trauma academic medical center. Patients who were intubated in the ED or en route to the ED between October 1, 2013, and October 1, 2014, were eligible for inclusion if they met the following criteria: aged 18 years or older, 24 hr or more on mechanically ventilated support receiving continuous sedation and/or analgesia during the first 48 hr of admission, and a hospital stay of 6 days or more. There were 205 patients identified; 104 failed inclusion, 101 were enrolled, and 62 were excluded. Thirty-nine patients (94.9%) had an RASS goal implemented in the ED, of which 37 patients (81.1%) had an RASS goal set by an ED physician. Assessment of the RASS was found to be inconsistent, as 56.8% of patients were evaluated by an ED nurse within 1 hr of sedative initiation. Of the 37 patients who had an RASS goal in the ED, 18.9% achieved their goal in the ED. A review of sedation prescribing revealed that 39% received a regimen of varied combinations of continuous infusions of propofol, dexmedetomidine, and midazolam throughout admission, 33% received a regimen of 2 of the aforementioned drugs, and 28% received only propofol. Median extubation time was 129 hr. Seven patients expired within 180 days of admission. The assessment of the RASS was a common practice, but there were inconsistencies in measurement. A limited number of patients achieved their RASS goal in the ED. These results support a provider and nursing knowledge deficit regarding RASS goal setting, proper documentation of RASS measurement, and the need for appropriate assessments.
An Interprofessional Web-Based Teaching Module to Enhance Competency of the Advanced Practice Nursing Clinical Education in the Emergency Department
Authors: Ro Kumhee , Weiland Christy , Sin Mo-Kyung
Published: May 2018

Many advanced practice registered nursing (APRN) students struggle to thrive in their clinical rotation due to the wide variability in their clinical knowledge. To address the variability and gaps in knowledge, we created an interprofessional web-based, self-directed curriculum for APRN students that is clinically relevant and specific to the emergency department (ED) rotation. The modules are a product of collaboration between the medical, nursing, and pharmacy faculty at an academic medical center. This web-based curricular preceptorship model that incorporates new technology and innovation in clinical rotations can provide an opportunity to enhance the clinical education of the APRN students in the ED.
Experimentation in the agricultural EnlightenmentPlace, profit and norms of knowledge-making in eighteenth-century Germany
Authors: Phillips Denise
Published: May 2018

Most research into history of eighteenth-century experimentation has focused on the instrument-based traditions of natural philosophers and chemists. This article explores an alternate, but related, tradition: the experiments carried out by agricultural improvers. While authors interested in improving farming were aware of natural philosophical practices, they self-consciously devised different strategies in their own forms of experimentation. Experiments in the chemical and physical sciences generally sought to find universal laws operative everywhere; agricultural experimentation often explored the particular possibilities of a given place. The cost and likely economic success of an experiment was also worked explicitly into its design.
The contribution of non-essentialSchizosaccharomyces pombegenes to fitness in response to altered nutrient supply and target of rapamycin activity
Authors: Lie Shervi , Banks Peter , Lawless Conor , Lydall David , Petersen Janni
Published: May 2018

Nutrient fluctuations in the cellular environment promote changes in cell metabolism and growth to adapt cell proliferation accordingly. The target of rapamycin (TOR) signalling network plays a key role in the coordination of growth and cell proliferation with the nutrient environment and, importantly, nutrient limitation reduces TOR complex 1 (TORC1) signalling. We have performed global quantitative fitness profiling of the collection ofSchizosaccharomyces pombestrains from which non-essential genes have been deleted. We identified genes that regulate fitness when cells are grown in a nutrient-rich environment compared with minimal environments, with varying nitrogen sources including ammonium, glutamate and proline. In addition, we have performed the first global screen for genes that regulate fitness when both TORC1 and TORC2 signalling is reduced by Torin1. Analysis of genes whose deletions altered fitness when nutrients were limited, or when TOR signalling was compromised, identified a large number of genes that regulate transmembrane transport, transcription and chromatin organization/regulation and vesicle-mediated transport. The ability to tolerate reduced TOR signalling placed demands upon a large number of biological processes including autophagy, mRNA metabolic processing and nucleocytoplasmic transport. Importantly, novel biological processes and all processes known to be regulated by TOR were identified in our screens. In addition, deletion of 62 genes conserved in humans gave rise to strong sensitivity or resistance to Torin1, and 29 of these 62 genes have novel links to TOR signalling. The identification of chromatin and transcriptional regulation, nutritional uptake and transport pathways in this powerful genetic model now paves the way for a molecular understanding of how cells adapt to the chronic and acute fluctuations in nutrient supply that all eukaryotes experience at some stage, and which is a key feature of cancer cells within solid tumours.
Organizational complexity and demographic scale in primary states
Authors: Sandeford David S.
Published: May 2018

The relationship between organizational complexity and demographic scale is an enduring research problem at the intersection of the natural and social sciences and has far reaching implications for the study of social evolution, particularly the emergence and collapse of complex social organizations such as chiefdoms, states and empires. Anthropological models of social evolution universally assume that population growth plays a critical role in the development of organizational complexity; however, the relationship between organizational complexity and demographic scale has not been formalized and cross-culturally validated. There is a rich yet unsystematized body of diachronic organizational and demographic data describing the evolution of organizational complexity in 10 archaeologically known cases of primary state formation. Using this dataset, this essay proposes and tests a complex network model that describes state societies as discrete, self-similar, hierarchical social networks. The model accurately describes how organizational complexity and population scale in all cases. The complex network architecture of state societies suggests that further advances in our understanding of modern social organization may be found by a deeper investigation of the role of human nature in the evolution of human societies.
Quantification and optimization of ADF-STEM image contrast for beam-sensitive materials
Authors: Gnanasekaran Karthikeyan , de With Gijsbertus , Friedrich Heiner
Published: May 2018

Many functional materials are difficult to analyse by scanning transmission electron microscopy (STEM) on account of their beam sensitivity and low contrast between different phases. The problem becomes even more severe when thick specimens need to be investigated, a situation that is common for materials that are ordered from the nanometre to micrometre length scales or when performing dynamic experiments in a TEM liquid cell. Here we report a method to optimize annular dark-field (ADF) STEM imaging conditions and detector geometries for a thick and beam-sensitive low-contrast specimen using the example of a carbon nanotube/polymer nanocomposite. We carried out Monte Carlo simulations as well as quantitative ADF-STEM imaging experiments to predict and verify optimum contrast conditions. The presented method is general, can be easily adapted to other beam-sensitive and/or low-contrast materials, as shown for a polymer vesicle within a TEM liquid cell, and can act as an expert guide on whether an experiment is feasible and to determine the best imaging conditions.
Functionalization of 3-chloroformylcoumarin to coumarin Schiff bases using reusable catalyst: an approach to molecular docking and biological studies
Authors: Kumbar Suresh S. , Hosamani Kallappa M. , Gouripur Gangadhar C. , Joshi Shrinivas D.
Published: May 2018

Recently, heterogeneous catalysts have been explored eximiously in the synthesis of heterocyclic compounds. Therefore, here we used solid-supported heterogeneous silica sulfuric acid as a catalyst for the synthesis of Schiff's base of 3-chloroformylcoumarin in view of simplified procedure, reusability and acceptable efficiency, which are required in organic synthesis. An efficient and facile methodology is preferred for synthesis of a class of chromeno-3-substituted derivatives (
1a–1l
) with good yields. The molecular docking results showed excellent binding interactions with the
Mycobacterium tuberculosis
InhA-D148G mutant (PDB: 4DQU). The same biomolecules were screened for their
in vitro
anti-tubercular activity against the
M.tb
H37Rv strain and antimicrobial studies. Physico-chemistry, toxicity prediction with IC50 value and bioactivity score were also calculated for title compounds. Most active compounds were further tested for cytotoxicity studies and exhibited low-level cytotoxicity against Vero cells. The suggested conjugates are promising lead compounds for the subsequent investigation in search of new anti-tubercular agents. All the conjugates were obtained within the range and followed the Lipinski rule of 5, indicating more ‘drug-like’ nature.
High pregnancy rates in humpback whales (Megaptera novaeangliae) around the Western Antarctic Peninsula, evidence of a rapidly growing population
Authors: Pallin Logan J. , Baker C. Scott , Steel Debbie , Kellar Nicholas M. , Robbins Jooke , Johnston David W. , Nowacek Doug P. , Read Andrew J. , Friedlaender Ari S.
Published: May 2018

Antarctic humpback whales are recovering from near extirpation from commercial whaling. To understand the dynamics of this recovery and establish a baseline to monitor impacts of a rapidly changing environment, we investigated sex ratios and pregnancy rates of females within the Western Antarctic Peninsula (WAP) feeding population. DNA profiling of 577 tissue samples (2010–2016) identified 239 males and 268 females. Blubber progesterone levels indicated 63.5% of the females biopsied were pregnant. This proportion varied significantly across years, from 36% in 2010 to 86% in 2014. A comparison of samples collected in summer versus fall showed significant increases in the proportion of females present (50% to 59%) and pregnant (59% to 72%), consistent with demographic variation in migratory timing. We also found evidence of annual reproduction among females; 54.5% of females accompanied by a calf were pregnant. These high pregnancy rates are consistent with a population recovering from past exploitation, but appear inconsistent with recent estimates of WAP humpback population growth. Thus, our results will help to better understand population growth potential and set a current baseline from which to determine the impact of climate change and variability on fecundity and reproductive rates.
Improving the signal subtle feature extraction performance based on dual improved fractal box dimension eigenvectors
Authors: Chen Xiang , Li Jingchao , Han Hui , Ying Yulong
Published: May 2018

Because of the limitations of the traditional fractal box-counting dimension algorithm in subtle feature extraction of radiation source signals, a dual improved generalized fractal box-counting dimension eigenvector algorithm is proposed. First, the radiation source signal was preprocessed, and a Hilbert transform was performed to obtain the instantaneous amplitude of the signal. Then, the improved fractal box-counting dimension of the signal instantaneous amplitude was extracted as the first eigenvector. At the same time, the improved fractal box-counting dimension of the signal without the Hilbert transform was extracted as the second eigenvector. Finally, the dual improved fractal box-counting dimension eigenvectors formed the multi-dimensional eigenvectors as signal subtle features, which were used for radiation source signal recognition by the grey relation algorithm. The experimental results show that, compared with the traditional fractal box-counting dimension algorithm and the single improved fractal box-counting dimension algorithm, the proposed dual improved fractal box-counting dimension algorithm can better extract the signal subtle distribution characteristics under different reconstruction phase space, and has a better recognition effect with good real-time performance.
Mammoth grazers on the ocean's minuteness: a review of selective feeding using mucous meshes
Authors: Conley Keats R. , Lombard Fabien , Sutherland Kelly R.
Published: May 2018

Mucous-mesh grazers (pelagic tunicates and thecosome pteropods) are common in oceanic waters and efficiently capture, consume and repackage particles many orders of magnitude smaller than themselves. They feed using an adhesive mucous mesh to capture prey particles from ambient seawater. Historically, their grazing process has been characterized as non-selective, depending only on the size of the prey particle and the pore dimensions of the mesh. The purpose of this review is to reverse this assumption by reviewing recent evidence that shows mucous-mesh feeding can be selective. We focus on large planktonic microphages as a model of selective mucus feeding because of their important roles in the ocean food web: as bacterivores, prey for higher trophic levels, and exporters of carbon via mucous aggregates, faecal pellets and jelly-falls. We identify important functional variations in the filter mechanics and hydrodynamics of different taxa. We review evidence that shows this feeding strategy depends not only on the particle size and dimensions of the mesh pores, but also on particle shape and surface properties, filter mechanics, hydrodynamics and grazer behaviour. As many of these organisms remain critically understudied, we conclude by suggesting priorities for future research.
Epigenetic regulation of transcriptional plasticity associated with developmental song learning
Authors: Kelly Theresa K. , Ahmadiantehrani Somayeh , Blattler Adam , London Sarah E.
Published: May 2018

Ethologists discovered over 100 years ago that some lifelong behavioural patterns were acquired exclusively during restricted developmental phases called critical periods (CPs). Developmental song learning in zebra finches is one of the most striking examples of a CP for complex learned behaviour. After post-hatch day 65, whether or not a juvenile male can memorize the song of a ‘tutor' depends on his experiences in the month prior. If he experienced a tutor, he can no longer learn, but if he has been isolated from hearing a tutor the learning period is extended. We aimed to identify how tutor experience alters the brain and controls the ability to learn. Epigenetic landscapes are modulated by experience and are able to regulate the transcription of sets of genes, thereby affecting cellular function. Thus, we hypothesized that tutor experiences determine the epigenetic landscape in the auditory forebrain, a region required for tutor song memorization. Using ChIPseq, RNAseq and molecular biology, we provide evidence that naturalistic experiences associated with the ability to learn can induce epigenetic changes, and propose transcriptional plasticity as a mediator of CP learning potential.
The biogeographical imprint of mass extinctions
Authors: Kocsis Ádám T. , Reddin Carl J. , Kiessling Wolfgang
Published: May 2018

Mass extinctions are defined by extinction rates significantly above background levels and have had substantial consequences for the evolution of life. Geographically selective extinctions, subsequent originations and species redistributions may have changed global biogeographical structure, but quantification of this change is lacking. In order to assess quantitatively the biogeographical impact of mass extinctions, we outline time-traceable bioregions for benthic marine species across the Phanerozoic using a compositional network. Mass extinction events are visually recognizable in the geographical depiction of bioregions. The end-Permian extinction stands out with a severe reduction of provinciality. Time series of biogeographical turnover represent a novel aspect of the analysis of mass extinctions, confirming concentration of changes in the geographical distribution of benthic marine life.
Exploring the genetic correlations of antisocial behavior and life history traits
Authors: Tielbeek Jorim J. , Barnes J.C. , Popma Arne , Polderman Tinca J.C. , Lee James J. , Perry John R.B. , Posthuma Danielle , Boutwell Brian B.
Published: May 2018

Prior evolutionary theory provided reason to suspect that measures of development and reproduction would be correlated with antisocial behaviors in human and non-human species. Behavioral genetics has revealed that most quantitative traits are heritable, suggesting that these phenotypic correlations may share genetic etiologies. We use GWAS data to estimate the genetic correlations between various measures of reproductive development (N= 52,776 – 318,863) and antisocial behavior (N= 31,968). Our genetic correlation analyses demonstrate that alleles associated with higher reproductive output (number of children ever born, rg=0.50, p=.0065) were positively correlated with alleles associated with antisocial behavior, whereas alleles associated with more delayed reproductive onset (age of first birth, rg=-.64, p=.0008) were negatively associated with alleles linked to antisocial behavior. Ultimately, these findings coalesce with evolutionary theories suggesting that increased antisocial behaviors may partly represent a faster life history approach, which may be significantly calibrated by genes.