bluuebunny/crossref_metadata_2025 huggingface dataset:
Formation of interstellar methanol ice prior to the heavy CO freeze-out stage
Authors: Qasim D. , Chuang K.-J. , Fedoseev G. , Ioppolo S. , Boogert A. C. A. , Linnartz H.
Published: January 2018

Context.The formation of methanol (CH3OH) on icy grain mantles during the star formation cycle is mainly associated with the CO freeze-out stage. Yet there are reasons to believe that CH3OH also can form at an earlier period of interstellar ice evolution in CO-poor and H2O-rich ices.

Aims.This work focuses on CH3OH formation in a H2O-rich interstellar ice environment following the OH-mediated H-abstraction in the reaction, CH4+ OH. Experimental conditions are systematically varied to constrain the CH3OH formation yield at astronomically relevant temperatures.

Methods.CH4, O2, and hydrogen atoms are co–deposited in an ultrahigh vacuum chamber at 10–20 K. OH radicals are generated by the H + O2surface reaction. Temperature programmed desorption – quadrupole mass spectrometry (TPD–QMS) is used to characterize CH3OH formation, and is complemented with reflection absorption infrared spectroscopy (RAIRS) for CH3OH characterization and quantitation.

Results.CH3OH formation is shown to be possible by the sequential surface reaction chain, CH4+ OH → CH3+ H2O and CH3+ OH → CH3OH at 10–20 K. This reaction is enhanced by tunneling, as noted in a recent theoretical investigation Lamberts et al. (2017, A&A, 599, A132). The CH3OH formation yield via the CH4+ OH route versus the CO + H route is approximately 20 times smaller for the laboratory settings studied. The astronomical relevance of the new formation channel investigated here is discussed.
A perfect reconstruction property for PDE-constrained total-variation minimization with application in Quantitative Susceptibility Mapping
Authors: Bredies Kristian , Vicente David
Published: January 2018

We study the recovery of piecewise constant functions of finite bounded variation (BV) from their image under a linear partial differential operator with unknown boundary conditions. It is shown that minimizing the total variation (TV) semi-norm subject to the associated PDE-constraints yields perfect reconstruction up to a global constant under a mild geometric assumption on the jump set of the function to reconstruct. The proof bases on establishing a structural result about the jump set associated with BV-solutions of the homogeneous PDE. Furthermore, we show that the geometric assumption is satisfied up to a negligible set of orthonormal transformations. The results are then applied to Quantitative Susceptibility Mapping (QSM) which can be formulated as solving a two-dimensional wave equation with unknown boundary conditions. This yields in particular that total variation regularization is able to reconstruct piecewise constant susceptibility distributions, explaining the high-quality results obtained with TV-based techniques for QSM.
Experimental and Theoretical Study of the Reaction Kinetics of 2,5-Dimethylterephthalonitrile Bromination Compared to 1,4-Dimethylbenzene Bromination
Authors: Villalba Cibeli , de C Rozada Thiago , dos Santos Fábio , Scorsin Leandro , Garcia Jarem , Fiorin Barbara
Published: January 2018

Experimental and theoretical studies showed the differences observed in the benzylic tetrabromination reactions in 2,5-dimethylterephthalonitrile compared to 1,4-dimethylbenzene. It was observed that the compound containing the nitrile substituent underwent a slower bromination reaction, with the formation of four intermediate compounds, while for the compound without substituents, the reaction was faster and only two intermediate compounds were observed.
Expeditious Scalable Catalyst-Free One-Pot Synthesis of 4-Alkoxy-5-amino-3-methylthiophene-2-carbonitriles via Sequential Reactions­ of Lithiated Alkoxyallenes with Isothiocyanates and 2-Bromoacetonitrile
Authors: Nedolya Nina , Trofimov Boris , Tarasova Olga , Albanov Alexander
Published: January 2018

A synthetically simple and convenient approach to tetrasubstituted thiophenes with rare combination of the alkoxy, amino, and cyano groups has been developed. The assembly of polyfunctionalized thiophene ring is implemented in one preparative step by sequential addition of isothiocyanate and 2-bromoacetonitrile to the lithiated (with n-BuLi) alkoxyallene. The reaction proceeds through in situ formation and intramolecular cyclization of cyanomethyl 2-alkoxy-N-buta-2,3-dienimidothioate (1-aza-1,3,4-triene).
Assessing Cancer Signal during Oral Antiplatelet Therapy in the Food and Drug Administration Adverse Event Reporting System: Mission Impossible
Authors: Serebruany Victor , Kim Moo , Thevathasan Christian , Marciniak Thomas
Published: January 2018

Whether aggressive prolonged dual antiplatelet therapy (DAPT) promotes solid cancer risks remains a critical unsolved issue. Since the evidence from randomized trials, affiliated U.S. Food and Drug Administration (FDA) reviews, meta-analyses, and national registries is mixed, the search is ongoing. The FDA Adverse Event Reporting System (FAERS) is a global passive surveillance repository requiring mandatory updates for serious events. We assessed the frequencies of co-reporting any cancers with oral antiplatelet agent (OAA) strategies in FAERS. We examined the entire FAERS database (n = 8,604,889) with regard to monotherapy or DAPT with OAA, suspected causative role, and co-reporting any cancers (n = 433,111). We extracted cancer cases during monotherapy with aspirin (20,984 out of 462,371 or 4.54%), clopidogrel (2,797 out of 62,791 or 4.45%), prasugrel (119 out of 4,364 or 2.73%), and ticagrelor (144 out of 8.268 or 1.71%). DAPT with clopidogrel reported (2,453 out of 58,101, or 4.22%); prasugrel (162 out of 4,036, or 4.01%); and ticagrelor (195 out of 5,302 or 3.68%) cancer reports all on top of aspirin. We conclude that FAERS is currently unreliable for adequate assessment of cancer risks during DAPT. The retrieved evidence appears random and sporadic, while associated cancers are heavily underreported or/and missed. Without stricter rules, better surveillance, and enforcements, oncology outcome research options in FAERS are challenging.
Evaluation of Experience with Lower Extremity Arterial Injuries at an Urban Trauma Center
Authors: Franz Randall , Hill Joshua , Lieber Michael , Galante John , Tanga Christopher
Published: January 2018

Lower extremity arterial injuries (LEAIs) can be complicated injuries resulting in limb loss and death. Patients with LEAI often have multiple injuries increasing the risk for morbidity and mortality. We sought to evaluate the incidence and management of LEAI and to define associations between injuries and outcomes. We performed a retrospective review of LEAI at an urban level-1 trauma center from April 2005 to April 2015. Chi-square tests were used to compare independent groups with respect to mortality and amputation. Means were compared between independent groups using two-sample t-tests. From April 2005 to April 2015, 208 arterial injuries occurred in 163 patients. The majority (80.4%) suffered concomitant lower extremity injuries with 35.6% suffering systemic injuries. Surgical intervention was required for 72.1% of injuries. Amputation rate was 14.7%. Mortality rate was 8.0%. Data from 2010 to 2015 were more specifically analyzed. Injury severity score (ISS) was higher with fatalities (37 ± 13.16 vs. 11.8 ± 8.51, p < 0.0001) and in patients requiring an amputation (25.4 ± 15.32 compared with 11.6 ± 9.05, p = 0.0015). Popliteal artery injury was most likely to require an amputation (odds ratio [OR] = 2.9, p = 0.04). Mortality was more likely when systemic injuries were present (OR = 18.1, p = 0.0005). The majority of patients with arterial injuries require surgical management, most often with open surgical techniques. Arterial injuries associated with systemic injuries, blunt injury mechanisms, and higher ISS are at a significantly increased risk of mortality.
Intra-Arterial Thrombolytic Therapy Is Not a Therapeutic Option for Filler-Related Central Retinal Artery Occlusion
Authors: Chen Yi-Chun , Wu Hsiu-Mei , Chen Shih-Jen , Lee Han-Jui , Lirng Jiing-Feng , Lin Chung-Jung , Luo Chao-Bao , Guo Wan-Yuo , Chang Feng-Chi
Published: January 2018

Cosmetic facial filler-related central retinal artery occlusion (CRAO) is a devastating complication of facial hyaluronic acid (HA) injection and can be managed by intra-arterial thrombolytic therapy (IATT). The authors report on a 20-year-old woman who developed unilateral CRAO due to facial HA injection and who, despite prompt IATT, lost vision. A review of the related literature found 14 other female patients who developed cosmetic facial filler-related CRAO and accepted IATT management. In no case was vision loss clinically improved. IATT is not an effective preventive treatment of dermal filler-associated CRAO. The authors suggest careful preprocedural patient selection to prevent this complication.
Impact of Short Bowel Syndrome on Quality of Life and Family: The Patient's Perspective
Authors: Pederiva Federica , Khalil Basem , Morabito Antonino , Wood Sarah
Published: January 2018

Background Short bowel syndrome (SBS) has an impact on children and their families not only physically, but also emotionally, mentally, and socially. This study aimed to evaluate quality of life and family impact in patients with SBS, using the Pediatric Quality of Life Inventory (PedsQL) measurement model.

Materials and Methods PedsQL questionnaires were administered to patients with SBS followed at the Pediatric Surgery of Royal Manchester Children's Hospital. The scores were compared between two groups differing in age (children <5 y vs. >5 y) and with known-groups from literature published by Varni et al.

Results Forty-three patients were sent the questionnaires, and 30 (70%, 17 < 5 and 13 > 5) responded. Family Impact Module failed to distinguish between families of children younger and older than 5 years of age. In contrast, it distinguished between families with SBS children and the ones with children in a long-term care facility. Healthcare satisfaction was worse in families of children over 5 years regarding information received, inclusion of the family, and communication. When compared with normal population, SBS children scored worse on Generic Core Scales for all domains except for emotional functioning.

Conclusion Although advances have been made on the treatment of children with SBS, and improvements have been reached on home PN, this condition is still significantly affecting the quality of life of children and their families. The future quality control of medical care must have greater focus on psychosocial and emotional functioning, aiming for the best possible quality of life.
Temporally and spatially resolved ion dynamics of droplet-based laser-produced tin plasmas in lateral expansion direction
Authors: Brandstätter Markus , Gambino Nadia , Abhari Reza S.
Published: January 2018

The temporal and spatial plasma ion dynamics in the lateral direction generated by a Nd:YAG laser irradiated droplet target were studied with a hemispherical electrostatic probe array. The ion dynamics produced from 1.6 × 10+11 W/cm2 irradiation with a pulse duration of 23.9 ns FWHM were measured simultaneously from 50° to 130° from the laser axis with radial probe distances d from 1.5 to 7 cm to the plasma ignition point at an ambient argon gas pressure of 2 × 10−2 mbar. The collected ion charge and expansion velocities were derived from the ion profiles. It was found that the collected ion charge Q around the droplet scales with Q ∼ d−2 indicating that the main driving mechanism relates to the three-dimensional plasma expansion and not recombination processes. An anisotropic ion bulk expansion in the laser forward and backward propagation direction was deduced ranging from 2.9 cm/μs to 2.1 cm/μs, respectively. The gradients of the ion bulk expansion velocities along d were found to be constant within the error margin across the measurement range. The leading edge of the ion profiles showed an anisotropic behavior around the droplet, suggesting recombination effects scale differently in the laser forward and backward propagation direction which was linked to the higher expansion velocities in the laser forward direction. The broadening of the ion current waveform with increasing radial distance was studied and it was observed that the ion profile shape did not change for d > 5 cm, suggesting negligible recombination.
Ductile–brittle transition in transverse isotropic fibrous networks
Authors: Luo Guoquan , Shi Liping , Li Mingwei , Zhong Yesheng , He Xiaodong , Wang Jiazhi
Published: January 2018

Anisotropic fibrous networks, especially transverse isotropic fibrous networks, are widely used to model the microstructures of biological tissues, polymer gels, fibrous thermal insulations, and other fibrous materials. In this letter, we build a three-dimensional transverse isotropic fibrous network model and study its mechanical properties along the through-thickness direction. We propose a measurement of anisotropy for transverse isotropic fibrous networks and then study the influence of anisotropy on the networks' mechanical properties, including its elastic modulus, maximum elongation, and stress–strain curve, by means of finite-element simulation. We also study theoretically the influence of anisotropy on maximum elongation. We find that as the anisotropy of the networks becomes stronger, the elastic modulus decreases and the maximum elongation increases, indicating a transition in mechanical properties from brittle to ductile. We identify this transition as the “ductile–brittle transition.” This transition can help guide the design and regulate the mechanical properties of a transverse isotropic fibrous network.
Compositionally driven giant strain and electrostrictive co-efficient in lead free NBT-BT-BFO system
Authors: Duraisamy Dhayanithi , Venkatesan Giridharan Nambi
Published: January 2018

As lead free alternatives, bismuth based ferroelectric ceramics are currently under intense investigation. Here, the authors report on the development of a lead free (1-2x)Na0.5Bi0.5TiO3-xBaTiO3-xBiFeO3: NBT-BT-BFO [x = 0.01, 0.03, 0.05, 0.07, and 0.09] ceramic. Rietveld analysis of the powder diffraction data reveals the existence of compositionally driven single and two phase combinations. The compositions corresponding to x = 0.01 and 0.03 are found to be crystallized in a monoclinic (Cc) system, whereas the compositions corresponding to x =0.05, 0.07, and 0.09 are found to have the coexistence of [monoclinic (Cc) + Cubic (pm-3m)] and [Tetragonal (P4bm) + Cubic (pm-3m)] phases. A high electric field induced strain has been obtained for x = 0.07, which can be attributed to the polarization extension mechanism at the proximity of the phase boundary between polar and nonpolar phases. Further, the manufactured ceramic is characterized by Smax/Emax of 858 pm/V and an electrostrictive co-efficient (Q33) of 0.045 m4 C−2 much higher than the values of well-established Pb(Zr,Ti)O3 and other lead free ceramics.
Effects of potassium on kesterite solar cells: Similarities, differences and synergies with sodium
Authors: Haass S. G. , Andres C. , Figi R. , Schreiner C. , Bürki M. , Tiwari A. N. , Romanyuk Y. E.
Published: January 2018

Addition of alkali dopants is essential for achieving high-efficiency conversion efficiency of thin film solar cells based on chalcogenide semiconductors like Cu(In,Ga)Se2 (CIGS) and Cu2ZnSn(S,Se)4 (CZTSSe also called kesterite). Whereas the treatment with potassium allows boosting the performance of CIGS solar cells as compared to the conventional sodium doping, it is debated if similar effects can be expected for kesterite solar cells. Here the influence of potassium is investigated by introducing the dopant during the solution processing of kesterite absorbers. It is confirmed that the presence of potassium leads to an enhanced grain growth and a ten-fold lower potassium concentration is sufficient for obtaining grain size similar to sodium-containing absorbers. Potassium is located predominantly at grain boundaries and it suppresses incorporation of sodium into the absorber layer. The potassium doping increases the apparent carrier concentration to ∼2×1016 cm-3 for a potassium concentration of 0.2 at%. The potassium-doped solar cells yield conversion efficiency close to 10%, on par with only sodium-doped samples. Co-doping with potassium and sodium has not revealed any beneficial synergetic effects and it is concluded that both dopants exhibit similar effects on the kesterite solar cell performance.
Effects of low- to medium-angle grain boundaries on creep properties of superalloy
Authors: Zhang Chengjiang , Hu Weibing , Liu Chenyu , Zhao Yunsong , Shang Jing , Wen Zhixun
Published: January 2018

The creep properties of Ni-based bicrystal specimens with low- to medium-angle grain boundaries are investigated at 1100°C and 130 MPa with two misorientation angles prepared by double-seed solidification. Experimental results show that the angle of the grain boundary with respect to the stretching direction has a strong effect on creep life. Molecular dynamics simulations show that the effect of the grain boundary on the neighbouring dislocation density is related to the grain boundary angle. A creep constitutive model with the grain boundary angle and the initial damage rate can be adopted to describe the creep damage evolution. The model is then modified according to the molecular dynamics simulation and experimental results to give more accurate predictions of creep life.
Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the SMU, Slovakia and the BIPM in 60Co gamma radiation
Authors: Kessler C , Burns D , Durný N
Published: January 2018

A key comparison of the standards for air kerma of the Slovak Institute of Metrology (SMU), Slovakia and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in June 2017. The comparison result, evaluated as a ratio of the SMU and the BIPM standards for air kerma, is 1.0042 with a combined standard uncertainty of 2.7 × 10−3. The results for an indirect comparison made at the same time are consistent with the direct results at the level of 2 parts in 104. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database.

Main text

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.

The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Fractal Uncertainty for Transfer Operators
Authors: Dyatlov Semyon , Zworski Maciej
Published: January 2018

We show directly that the fractal uncertainty principle of Bourgain–Dyatlov [3] implies that there exists σ > 0 for which the Selberg zeta function (1.2) for a convex co-compact hyperbolic surface has only finitely many zeros with $ \textrm{Re}\, s \geq \frac 12 - \sigma $. That eliminates advanced microlocal techniques of Dyatlov–Zahl [6], though we stress that these techniques are still needed for resolvent bounds and for possible generalizations to the case of nonconstant curvature.
“Isolated” Suprascapular Neuropathy: Compression, Traction, or Inflammation?
Authors: Le Hanneur Malo , Maldonado Andres A , Howe Benjamin M , Mauermann Michelle L , Spinner Robert J
Published: January 2018

BACKGROUND

Several hypotheses have been proposed for the pathophysiology of suprascapular nerve (SSN) palsy, including compression, traction, and nerve inflammation.

OBJECTIVE

To provide insight into the pathophysiology of isolated nontraumatic SSN palsy by performing critical reinterpretations of electrodiagnostic (EDX) studies and magnetic resonance (MR) images of patients with such diagnosis.

METHODS

We retrospectively reviewed all patients referred to our institution for the past 20 yr with a diagnosis of nontraumatic isolated suprascapular neuropathy who had an upper extremity EDX study and a shoulder or brachial plexus MR scan. Patient charts were reviewed to analyze their initial clinical examination, and their original EDX study and MR images were reinterpreted by an experienced neurologist and a musculoskeletal radiologist, respectively, both blinded from the authors’ hypothesis and from each other's findings.

RESULTS

Fifty-nine patients were included. Fifty of them (85%) presented with at least 1 finding that was inconsistent with an isolated SSN palsy. Forty patients (68%) had signs on physical examination beyond the SSN distribution. Thirty-one patients (53%) had abnormalities on their EDX studies not related to the SSN. Twenty-two patients (37%) had denervation atrophy in other muscles than the spinati, or neural hyperintensity in other nerves than the SSN on their MR scans, without any evidence of SSN extrinsic compression.

CONCLUSION

The great majority of patients with presumed isolated SSN palsy had clinical, electrophysiological, and/or imaging evidence of a more diffuse pattern of neuromuscular involvement. These data strongly support an inflammatory pathophysiology in many cases of “isolated” SSN palsy.
Using Critical Care Simulations to Prepare Nursing Students for Capstone Clinical Experiences
Authors: Smallheer Benjamin , Hunt Jennifer , Smith Judson
Published: January 2018

The purpose of this innovative learning strategy was to decrease students' fear and anxiety within the critical care environment before the initiation of a critical care capstone clinical experience by enhancing their familiarity of the critical care environment through deliberate practice and experiential learning. This will in turn increase student knowledge and competence in the critical care setting.

Critical care units are often used during a capstone clinical experience to enhance critical thinking and clinical reasoning. Student preparation for these rotations, however, is varied and often inadequate. The resulting fear and anxiety impair learning and also contribute to an unsafe environment for this at-risk population.

Before the capstone experience, students participated in 3 simulation experiences, each addressing a core concept of critical care nursing. Faculty engaged students during the simulations, while modeling the confidence and critical thinking of a critical care nurse.

After both the critical care simulation and the capstone rotation, students stated that the simulation allowed them the time in a safe environment to critically think through the steps to care for critical patients before the capstone rotation. The experience provided them with increased confidence necessary to discharge the responsibilities of a critical care nurse—attention to critical thinking and reasoning.

Mindfully constructed simulations with clear objectives help to inoculate the student against fears associated with high-risk patients. This decrease in fear and anxiety before a hands-on clinical experience may improve patient safety. More confident students are also better able to engage in both experiential and deliberate learning, resulting in a more enhanced and meaningful clinical experience.
Evaluating Sleep in a Surgical Trauma Burn Intensive Care Unit
Authors: Longley Laura , Simons Theresa , Glanzer Luella , Du Claire , Trinks Heather , Letzkus Lisa , Quatrara Beth
Published: January 2018

Background

Evidence points to the adverse effects of sleep deprivation on a person’s health. Despite decades of attention to the issue, patients, particularly those in the intensive care unit (ICU), continue to suffer.

Objective

The purpose of this pilot study was to examine patients’ perceptions of their sleep experience in the surgical trauma burn ICU and identify contributing factors.

Methodology

Patients were administered the 6-question Richards-Campbell Sleep Questionnaire (RCSQ) consisting of a 0- to 100-mm scale, with a low score indicating poor sleep quality. They were also asked an additional open-ended question.

Results

Sixty patients participated. Data revealed a low overall RCSQ score of 43.6 of 100. Of the 5 validated questions on the RCSQ, the question with the lowest mean (35.6) targeted depth of sleep. The question pertaining to falling asleep immediately scored the highest at 52.2. The open-ended question revealed that 37% reported “interruptions” as the reason for not sleeping. Pain was also cited as a factor by 30%, with 11.7% citing discomfort from the bed as an irritant. An additional 21.6% reported noise as the central reason, with “pumps/monitor” noise as the most frequent culprit at 62%.

Discussion

The pilot study results demonstrate that most participants perceived their sleep as poor in quality. These results direct targeted interventions that can be incorporated to reduce sleep deprivation in ICUs.
Community, Public Policy, and Recovery from Mental Illness: Emerging Research and Initiatives
Authors: Castillo Enrico G. , Chung Bowen , Bromley Elizabeth , Kataoka Sheryl H. , Braslow Joel T. , Essock Susan M. , Young Alexander S. , Greenberg Jared M. , Miranda Jeanne , Dixon Lisa B. , Wells Kenneth B.
Published: January 2018

This commentary examines the roles that communities and public policies play in the definition and processes of recovery for adults with mental illness. Policy, clinical, and consumer definitions of recovery are reviewed, which highlight the importance of communities and policies for recovery. This commentary then presents a framework for the relationships between community-level factors, policies, and downstream mental health outcomes, focusing on macroeconomic, housing, and health care policies; adverse exposures such as crime victimization; and neighborhood characteristics such as social capital. Initiatives that address community contexts to improve mental health outcomes are currently under way. Common characteristics of such initiatives and select examples are discussed. This commentary concludes with a discussion of providers’, consumers’, and other stakeholders’ roles in shaping policy reform and community change to facilitate recovery.
Investigating the Model of Community-Based Case Management in the New South Wales Brain Injury Rehabilitation Program: A Prospective Multicenter Study
Authors: Simpson Grahame , Mitsch Virginia , Doyle Margaret , Forman Marcella , Young Denise , Solomon Vicki , MacPherson Margaret , Gillett Lauren , Strettles Barbara
Published: January 2018

Objective:

To investigate a model of community-based case management (CM).

Setting:

New South Wales (NSW) Brain Injury Rehabilitation Program (BIRP).

Participants:

All clinicians (N = 72) providing CM within 14 BIRP community rehabilitation teams.

Design:

A prospective, multicenter study.

Main Measures:

A purpose-designed survey.

Methods:

Participants from the 12 adult and 2 pediatric services (8 located in metropolitan areas, 6 in rural areas) completed a 3-part survey investigating their organizational context, clinical approach, and CM interventions. Between-groups analyses explored differences among individual services, as well as differences based on age (adult vs pediatric) and location (metropolitan vs rural).

Results:

All services provided a direct service model of CM. The underlying principles were uniform across services (more direct than indirect service provision; with more client-related than administrative-related tasks; more holistic than service-led in defining client needs; with decision making equally directed by staff and clients; and undertaking a more comprehensive than minimalist range of tasks). CM interventions included the provision of individual support, family support, advocacy, and community development alongside assessment, monitoring, referral, and liaison tasks. There were little differences in practice based on age or location.

Conclusion:

The NSW BIRP has drawn upon the results to produce a model of service for CM.
Quantitative Volumetric Imaging and Clinical Outcome Characterization of Symptomatic Concussion in 10- to 14-Year-Old Adolescent Athletes
Authors: Mac Donald Christine L. , Barber Jason , Wright Jason , Coppel David , De Lacy Nina , Ottinger Steve , Peck Suzanne , Panks Chris , Zalewski Kody , Sun Samantha , Temkin Nancy
Published: January 2018

Objective:

Prior work suggests that younger athletes may be more vulnerable to postconcussive syndrome. We investigated measures of clinical outcome and quantitative volumetric imaging in 10- to 14-year-old adolescent athletes to better understand the impact of concussion on this younger population.

Setting:

Outpatient clinics.

Participants:

Ten- to 14-year-old symptomatic pediatric sports concussion patients and typically developing active controls.

Design:

Prospective, observational multiclinic study.

Main Measures:

Demographics, magnetic resonance imaging, clinical assessments (neurocognitive function, postconcussive symptoms, mental health symptoms, quality of life).

Results:

Neuropsychological performance was comparable between groups while symptoms of mental health were discriminating and comprised the top regression model describing factors related to overall health behavior impairment. Concussion patients had smaller total brain volume as well as total intracranial volume in comparison with controls even though there was no difference on measures of natural development (age, height, weight, education, gender, and handedness).

Conclusions:

Findings indicate that 10- to 14-year-old concussion patients symptomatic at 1 month more likely exhibit mental health symptoms impairing health behavior than cognitive dysfunction. There may be a vulnerability for those with smaller brain volumes at the time of the exposure. The study provides new data to support further investigation into risk factors for prolonged symptoms in this younger athlete population.
Urinary Biomarkers to Predict Neonatal Acute Kidney Injury
Authors: Marin Terri , DeRossett Blair , Bhatia Jatinder
Published: January 2018

Acute kidney injury (AKI) occurs in approximately 30% of all infants hospitalized in the neonatal intensive care unit. About 40% of very low-birth-weight infants develop AKI, with an estimated mortality rate of 50% to 80%. Very low-birth-weight survivors have twice the risk of developing chronic renal disease later in life compared with their term counterparts. Current diagnostic modalities for AKI include serum creatinine and urine output; however, recent studies suggest that these measures are imprecise, as they may not change until 25% to 50% of renal function is lost. Urinary biomarkers may more accurately identify infants at risk for early AKI development. The purpose of this review is to discuss current research findings related to neonatal AKI risk factors, provide an overview of short- and long-term outcomes, describe innovative diagnostic approaches, and identify future research direction needed to improve prediction and intervention strategies associated with renal impairment.
How Does the United States Rank According to the World Breastfeeding Trends Initiative?
Authors: Cadwell Karin , Turner-Maffei Cynthia , Blair Anna , Brimdyr Kajsa , O'Connor Barbara
Published: January 2018

The World Breastfeeding Trends Initiative is an assessment process designed to facilitate an ongoing national appraisal of progress toward the goals of the United Nations Children's Fund (UNICEF)/World Health Organization (WHO) Global Strategy for Infant and Young Child Feeding. More than 80 countries have completed this national assessment, including the United States of America. This article describes the process undertaken by the US World Breastfeeding Trends Initiative team, the findings of the expert panel related to infant and young child feeding policies, programs, and practices and the ranking of the United States compared with the 83 other participating nations. Identified strengths of the United States include data collection and monitoring, especially by the Centers for Disease Control and Prevention, the US Baby-Friendly Hospital Initiative, and the United States Breastfeeding Committee. The absence of a national infant feeding policy, insufficient maternity protection, and lack of preparation for infant and young children feeding in emergencies are key targets identified by the assessment requiring concerted national effort.
Open Globe Injury: Demographic and Clinical Features
Authors: Sahin Atik Sevinc , Ugurlu Seyda , Egrilmez Emine Deniz
Published: January 2018

Background:

Open globe injuries (OGIs) are the main cause of visual impairment worldwide. The aim of this study was to evaluate the clinical features and the visual outcome of OGIs presented to the largest Teaching Hospital in Western part of Turkey.

Methods:

The study included patients presented with OGI between Jan 2009 and Dec 2013. Data including patient demographics, causes of injury, visual acuity (VA) at presentation, and final VA were collected. Ocular Trauma Scores (OTS) were calculated. Statistical analyses were performed to identify prognostic factors.

Results:

One hundred fifty-nine eyes of 156 patients with OGIs were included. The mean age was 36.89 ± 20.07 years. Significant male predominance was noted (77.6%). Domestic (28.3%) and work-related (22%) accidents were the most common causes of all OGIs. While some improvement in best corrected visual acuity (BCVA) after treatment has been noted in 68 eyes (55.7%), the final BCVA was equal to or worse than the initial BCVA in 54 eyes (44.3%). According to the OTS and final BCVA associations in our study, while the eyes with OGI included in OTS category 1 and 2 (n = 84) consist of 68.8% of all the OGI cases, 48.8% (n = 41) of them were classified as having a poor visual outcome. All of the eyes in OTS category 3 and 4 cases (n = 38) (31.2% of all the OGI cases) showed good visual outcome.

Conclusion:

Some clinical features may have a potential to correctly predict final visual outcomes. Although the OTS has not been fully validated yet, it could potentially be one of the best indicators available for the prognosis in OGI.
Decannulation and Airway Outcomes With Maxillomandibular Distraction in Treacher Collins and Nager Syndrome
Authors: Biskup Nataliya I. , Pan Brian S. , Elhadi-Babiker Haithem , Hathaway Ronald R. , van Aalst John , Gordon Christopher B.
Published: January 2018

Background:

Treacher Collins syndrome is a rare disorder (1/50,000 live births) with features that include hypoplastic orbitozygomatic complex with downward slanting eyes, and maxillary/mandibular retrusion. Obstructive sleep apnea and tracheostomy-dependence are common. This study presents the outcomes of skeletal distraction on avoidance of tracheostomy and decannulation in this patient population.

Methods:

The authors reviewed charts of all patients with Treacher Collins syndrome who underwent craniofacial reconstruction from 2003 to 2016. Primary outcome measures included decannulation of tracheostomy dependent patients and avoidance of tracheostomy. Secondary outcome measures included cephalometric parameters, polysomnography scores, and airway exposure scores on direct laryngoscopy.

Results:

Twenty-five patients underwent mandibular and maxillary advancement to resolve upper airway obstruction. Mandibular distraction was performed in 24 of 25 patients, and maxillary distraction in 14 of 25 patients. Maxillary distraction was combined with mandibular distraction in 13 of 17 to accomplish greater advancement and counter-clockwise rotation of the entire maxillary-mandibular complex. Six of 7 patients, 85.7%, avoided a tracheostomy and 39% (7 of 18) were decannulated. Cephalometric changes in sella-nasion-A point, sella-nasion-B , occlusal plane angle, and posterior airway space were equivalent between the groups who were able to clear their obstruction and those who were not.

Conclusions:

Treacher Collins is a very challenging disease in which to resolve airway obstruction. Thus, thorough evaluation of the entire airway for all levels of obstruction is critical to successful outcomes. Future collaborative efforts between multiple institutions can help to increase our understanding and effective management of this rare disease.
A Practical Suggestion for Prepare Dorsal Onlay Graft
Authors: Arslan Fatih , Yildiz Cemile Açikgoz
Published: January 2018

Nowadays, rhinoplasty is one of the most popular surgical procedures. Dorsal contour irregularities caused by various maneuvers, such as hump resection, are a major concern in patients who have undergone rhinoplasty. The most common graft used in this case is dorsal onlay graft which is made from sliced and crushed cartilage. Ear, nose and throat specialists usually use Swester table (mayo desk) for preparing the graft, if there is no other steril metal instrument. Crushed cartilage is done on a sterile gauze or on the tables’ cover, as a result cartilage may be contaminated with particules from the tables’ cover and sterile gauze.

The authors recommend using the steril pack of a new sterilized surgical instrument opened on the table for the slicing or crushing process. In this way, the cartilage can be spared from contamination and the loss of some cartilage to the table during slicing or crushing can be prevented.
Exploring Faculty Approaches to Feedback in the Simulated Setting
Authors: Roze des Ordons Amanda Lee , Cheng Adam , Gaudet Jonathan E. , Downar James , Lockyer Jocelyn M.
Published: January 2018

Introduction

Feedback in clinical education and after simulated experiences facilitates learning. Although evidence-based guidelines for feedback exist, faculty experience challenges in applying the guidelines. We set out to explore how faculty approach feedback and how these approaches align with current recommendations.

Methods

There is strong evidence for the following four components of feedback: feedback as a social interaction, tailoring content, providing specific descriptions of performance, and identifying actionable items. Faculty preceptors participated in feedback simulations followed by debriefing. The simulations were video recorded, transcribed, and analyzed qualitatively using template analysis to examine faculty approaches to feedback relative to evidence-informed recommendations.

Results

Recorded encounters involving 18 faculty and 11 facilitators yielded 111 videos. There was variability in the extent to which feedback approaches aligned with recommended practices. Faculty behaviors aligned with recommendations included a conversational approach, flexibly adapting feedback techniques to resident context, offering rich descriptions of observations with specific examples and concrete suggestions, achieving a shared understanding of strengths and gaps early on to allow sufficient time for problem-solving, and establishing a plan for ongoing development. Behaviors misaligned with guidelines included prioritizing the task of feedback over the relationship, lack of flexibility in techniques applied, using generic questions that did not explore residents' experiences, and ending with a vague plan for improvement.

Conclusions

Faculty demonstrate variability in feedback skills in relation to recommended practices. Simulated feedback experiences may offer a safe environment for faculty to further develop the skills needed to help residents progress within competency-based medical education.
Visual and auditory brain areas share a representational structure that supports emotion perception
Authors: Sievers Beau , Parkinson Carolyn , Kohler Peter J. , Hughes James M. , Fogelson Sergey V. , Wheatley Thalia
Published: January 2018

Emotionally expressive music and dance occur together across the world. This may be because features shared across the senses are represented the same way even in different sensory brain areas, putting music and movement in directly comparable terms. These shared representations may arise from a general need to identify environmentally relevant combinations of sensory features, particularly those that communicate emotion. To test the hypothesis that visual and auditory brain areas share a representational structure, we created music and animation stimuli with crossmodally matched features expressing a range of emotions. Participants confirmed that each emotion corresponded to a set of features shared across music and movement. A subset of participants viewed both music and animation during brain scanning, revealing that representations in auditory and visual brain areas were similar to one another. This shared representation captured not only simple stimulus features, but also combinations of features associated with emotion judgments. The posterior superior temporal cortex represented both music and movement using this same structure, suggesting supramodal abstraction of sensory content. Further exploratory analysis revealed that early visual cortex used this shared representational structure even when stimuli were presented auditorily. We propose that crossmodally shared representations support mutually reinforcing dynamics across auditory and visual brain areas, facilitating crossmodal comparison. These shared representations may help explain why emotions are so readily perceived and why some dynamic emotional expressions can generalize across cultural contexts.
Causal explanation of individual differences in human sensorimotor memory formation
Authors: Petitet Pierre , O’Reilly Jill X. , Gonçalves Ana M. , Salvan Piergiorgio , Kitazawa Shigeru , Johansen-Berg Heidi , O’Shea Jacinta
Published: January 2018

Sensorimotor cortex mediates the formation of adaptation memory. Individuals differ in the rate at which they acquire, retain, and generalize adaptation. We present a mechanistic explanation of the neurochemical and computational causes of this variation in humans. Neuroimaging identified structural, functional and neurochemical covariates of a computational parameter that determines memory persistence. To establish causality, we increased sensorimotor cortex excitability during adaptation, using transcranial direct current stimulation. As predicted, this increased retention. Inter-individual variance in the stimulation-induced E:I increase predicted the computational change, which predicted the memory gain. These relations did not hold, and memory was unchanged, with stimulation applied before adaptation. This cognitive state dependent effect was modulated by the BDNF val66met genetic polymorphism. Memory was enhanced by stimulation in Val/Val carriers only, implicating a mechanistic role for activity-dependent BDNF secretion. Sensorimotor cortex E:I causally determines the time constant of memory persistence, explaining phenotypic variation in adaptation decay.
COSSMO: Predicting Competitive Alternative Splice Site Selection using Deep Learning
Authors: Bretschneider Hannes , Gandhi Shreshth , Deshwar Amit G , Zuberi Khalid , Frey Brendan J
Published: January 2018

Motivation

Alternative splice site selection is inherently competitive and the probability of a given splice site to be used also depends strongly on the strength of neighboring sites. Here we present a new model named Competitive Splice Site Model (COSSMO), which explicitly models these competitive effects and predict the PSI distribution over any number of putative splice sites. We model an alternative splicing event as the choice of a 3’ acceptor site conditional on a fixed upstream 5’ donor site, or the choice of a 5’ donor site conditional on a fixed 3’ acceptor site. We build four different architectures that use convolutional layers, communication layers, LSTMS, and residual networks, respectively, to learn relevant motifs from sequence alone. We also construct a new dataset from genome annotations and RNA-Seq read data that we use to train our model.

Results

COSSMO is able to predict the most frequently used splice site with an accuracy of 70% on unseen test data, and achieve an R2 of 60% in modeling the PSI distribution. We visualize the motifs that COSSMO learns from sequence and show that COSSMO recognizes the consensus splice site sequences as well as many known splicing factors with high specificity.

Availability

Our dataset is available from http://cossmo.deepgenomics.com.

Contact

frey@deepgenomics.com

Supplementary information

Supplementary data are available at Bioinformatics online.
A saturation mutagenesis approach to understanding PTEN lipid phosphatase activity and genotype-phenotypes relationships
Authors: Mighell Taylor L. , Evans-Dutson Sara , O’Roak Brian j.
Published: January 2018

Phosphatase and tensin homolog (PTEN) is a tumor suppressor frequently mutated in diverse cancers. GermlinePTENmutations are also associated with a range of clinical outcomes, including PTEN hamartoma tumor syndrome (PHTS) and autism spectrum disorder (ASD). To empower new insights into PTEN function and clinically relevant genotype-phenotype relationships, we systematically evaluated the effect ofPTENmutations on lipid phosphatase activityin vivo. Using a massively parallel approach that leverages an artificial humanized yeast model, we derived high-confidence estimates of functional impact for 7,244 single amino acid PTEN variants (86% of possible). These data uncovered novel insights into PTEN protein structure, biochemistry, and mutation tolerance. Variant functional scores can reliably discriminate likely pathogenic from benign alleles. Further, 32% of ClinVar unclassified missense variants are phosphatase deficient in our assay, supporting their reclassification. ASD associated mutations generally had less severe fitness scores relative to PHTS associated mutations (p = 7.16×10-5) and a higher fraction of hypomorphic mutations, arguing for continued genotype-phenotype studies in larger clinical datasets that can further leverage these rich functional data.
Genomic copy-number loss is rescued by self-limiting production of DNA circles
Authors: Mansisidor Andrés , Molinar Temistocles , Srivastava Priyanka , Blitzblau Hannah , Klein Hannah , Hochwagen Andreas
Published: January 2018

Copy-number changes generate phenotypic variability in health and disease. Whether organisms protect against copy-number changes is largely unknown. Here, we show that Saccharomyces cerevisiae monitors the copy number of its ribosomal DNA (rDNA) and rapidly responds to copy-number loss with the clonal amplification of extrachromosomal rDNA circles (ERCs) from chromosomal repeats. ERC production is proportional to repeat loss and reaches a dynamic steady state that responds to the addition of exogenous rDNA copies. ERC levels are also modulated by RNAPI activity and diet, suggesting that rDNA copy number is calibrated against the cellular demand for rRNA. Lastly, we show that ERCs reinsert into the genome in a dosage-dependent manner, indicating that they provide a reservoir for ultimately increasing rDNA array length. Our results reveal a DNA-based mechanism for rapidly restoring copy number in response to catastrophic gene loss that shares fundamental features with unscheduled copy-number amplifications in cancer cells.