bluuebunny/crossref_metadata_2025 huggingface dataset:
Joy in the Journey: Navigating Leader/Learner Tensions
Authors: Johnson Shawn M.
Published: August 2019

Leaders who are engaged in sustained inquiry around a topic face a variety of tensions. These tensions include navigating the competing priorities associated with the leadership role as well as the learner role. Acknowledging the nuances of each of these roles requires an intentional balance to ensure that the roles work in service to one another, not in competition. Leaders can provide invaluable context around what they learn to ensure successful, lasting implementation. Leaders must also confront the reality of the “knowing‐doing” gap. The disparity between research and practice requires the learner to engage in careful inquiry as well as purposeful translation of those ideas to support the implementation of evidence‐based strategies into classrooms and schools. Leaders have a window to identify barriers to implementation and consider how to bridge the gap between research and practice. Developing practices that acknowledge these tensions are essential for school leaders who seek to build a coalition of learners and implement what they have learned to make a meaningful difference within their school communities. When leaders identify these tensions, they are empowered to share what they have learned in ways that will make a lasting difference in their schools.
Facial nerve atrophy in patients with amyotrophic lateral sclerosis: Evaluation with fast imaging employing steady‐state acquisition (FIESTA)
Authors: Miyata Mari , Kakeda Shingo , Hashimoto Tomoyo , Ide Satoru , Okada Kazumasa , Adachi Hiroaki , Korogi Yukunori
Published: August 2019

Background

In amyotrophic lateral sclerosis (ALS), motor neurons in the brainstem markedly deplete, whereas sensory neurons are less severely affected.

Purpose

To determine whether facial nerve (FN) measurement on 3D fast imaging employing steady‐state acquisition (FIESTA) is useful for ALS diagnosis.

Study Type

Retrospective.

Subjects

Fifteen ALS patients and 16 controls.

Field Strength/Sequence

3T FIESTA MR.

Assessment

The cross‐sectional area of the FN and cochlear nerve (CN) were measured, and the FN/CN ratio (FCR) was assessed. For qualitative assessment, the FN cross‐sectional area was compared with that of the CN and the following scores were assigned: score 1 (large), the FN is larger than the CN; score 2 (almost equal), the size difference between the FN and CN is within 10%; score 3 (small), the FN is smaller than the CN (10–50%); score 4 (significantly small), size of the FN is less than half the size of the CN.

Statistical Tests

The differences in FCR between the ALS patients and the controls were tested using the Wilcoxon Mann–Whitney U‐test. For the qualitative and quantitative assessments, we performed a receiver operating characteristic analysis for the diagnosis of ALS with an abnormal finding as score 3 or 4.

Results

The mean FCR was significantly smaller for ALS patients (0.71 ± 0.17) than for controls (0.95 ± 0.08) (P < 0.001) and the area under the curve was 0.93. When an FN score was 3 or 4, indicative of FN atrophy, the sensitivity and specificity values of FIESTA for discriminating ALS patients from controls were 93.3% (14/15) and 90.0% (18/20), respectively.

Data Conclusion

The FN atrophy revealed on FIESTA, which may reflect lower motor neuron impairment in ALS, allowed us to distinguish ALS patients from controls with a high degree of accuracy.

Level of Evidence: 3

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2020;51:757–766.
MRI does not predict pathologic complete response after neoadjuvant chemotherapy for breast cancer
Authors: Sener Stephen F. , Sargent Rachel E. , Lee Connie , Manchandia Tejas , Le‐Tran Vivian , Olimpiadi Yuliya , Zaremba Nicole , Alabd Andrew , Nelson Maria , Lang Julie E.
Published: August 2019

Background

This study assessed whether magnetic resonance imaging (MRI) could accurately predict pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) for patients receiving standardized treatment, pre‐ and post‐NAC MRI on the same instrumentation using a consistent imaging protocol, interpreted by a single breast fellowship‐trained radiologist.

Methods

A single‐institution retrospective analysis was performed including clinical, radiographic, and pathologic parameters for all patients with breast cancer treated with NAC from 2015 to 2018. Radiographic complete response (rCR) was defined as absence of suspicious MRI findings in the ipsilateral breast or lymph nodes. pCR was defined as the absence of invasive cancer or ductal carcinoma in‐situ in breast or lymph nodes after operation (ypT0N0M0).

Results

Data for 102 consecutive patients demonstrated that 44 (43.1%) had rCR and 41 (40.1%) had pCR. pCR occurred in 12 (25.0%) of 48 estrogen receptor positive (ER+) patients, 29 (53.7%) of 54 ER− patients, and 25 (52.1%) of 48 human epidermal growth factor receptor 2 positive patients. The positive predictive value for MRI after NAC was 84.5% and the negative predictive value was 72.7%. The accuracy rate for MRI was 78.6%. Of the 44 patients with rCR, 12 (27.3%) had residual cancer on the pathologic specimen after surgical excision.

Conclusion

rCR is not accurate enough to serve as a surrogate marker for pCR on MRI after NAC.
Ultrasound‐Guided Umbilical Venous Catheter Insertion With Alignment of the Umbilical Vein and Ductus Venosus
Authors: Kishigami Makoto , Shimokaze Tomoyuki , Enomoto Masahiro , Shibasaki Jun , Toyoshima Katsuaki
Published: August 2019

Previous studies have highlighted the importance of confirming the position of an umbilical venous catheter (UVC) tip by an ultrasound (US) examination. However, methods for preventing insertion into the portal circulation under US guidance have not yet been established. We report 15 cases in which a UVC was successfully passed through the ductus venosus by compressing the upper abdomen near the portal sinus of the liver to align the umbilical vein and ductus venosus under US guidance. The UVC was inserted into the correct position in 14 of the 15 neonates (93%) without complications.
The relationship between nonalcoholic fatty liver disease and pediatric congenital hypothyroidism patients
Authors: Pan Yu‐Wen , Tsai Meng‐Che , Yang Yao‐Jong , Chen Ming‐Yin , Chen Shou‐Yen , Chou Yen‐Yin
Published: August 2019

Previous studies have shown hypothyroidism was independently associated with nonalcoholic fatty liver disease (NAFLD) in adults, but few studies examined their relationships in pediatric populations. This study aimed to investigate the prevalence of NAFLD in pediatric congenital hypothyroidism (CHT) patients and to identify the association between CHT and NAFLD. This study enrolled pediatric CHT patients receiving levothyroxine treatment at one medical center from 2013 to 2014. Euthyroid subjects (ET) and transient hypothyroidism (THT) patients weaned off medication successfully after age 3 were selected for further comparison. Laboratory data including thyroid functions, liver functions, and metabolic profiles were obtained. The major outcome was the occurrence of NAFLD, diagnosed based on the findings of abdominal ultrasonography. One‐hundred and twenty‐nine subjects (47 in CHT, 47 in THT, and 35 in ET groups) were enrolled. The analysis showed higher fasting serum glucose, insulin, thyroxine (T4), and mean thyroid‐stimulating hormone (TSH) levels in the CHT group. NAFLD prevalence was higher in the CHT (23.4%) group than in the THT (8.5%) and the ET (5.7%) groups, demonstrating an increasing trend across three strata (X2linear‐by‐linear = 5.9, P < .05). The multivariate regression analysis showed obesity (β‐coefficient = 5.52, P < .05), CHT (β‐coefficient = 2.92, P < .05) and mean TSH levels (β‐coefficient = 0.24, P < .05) were independent risk factors for NAFLD. A positive correlation was found between TSH level and lipid profiles. CHT patients had higher risk of NAFLD despite treatment being initiated early in life. Close monitoring of metabolic profiles is warranted. Further research should examine ways to optimize the treatment for CHT patients in terms of prevention against NAFLD.
Navy diver with recurrent facial nerve baroparesis treated with eustachian tube balloon dilation
Authors: Utz Edward R. , Wise Sean R.
Published: August 2019

Facial nerve baroparesis is a rare complication of middle ear barotrauma reported almost exclusively in overpressure events related to diving and flying. Until the development of Eustachian tube balloon dilation, no diving compatible options existed to effectively and safely prevent recurrence. We present a case of a U.S. Navy diver with a history of repeated ipsilateral facial nerve paresis that occurred during diving. The patient underwent Eustachian tube balloon dilation of the affected side. Following surgery, the patient completed a recompression chamber simulated dive that allowed the patient to return to diving. The patient has been symptom‐free for 12 months following dilation.

Laryngoscope, 129:E412–E414, 2019
Efficacy of a silicone plug for patulous eustachian tube: A prospective, multicenter case series
Authors: Ikeda Ryoukichi , Oshima Takeshi , Mizuta Kunihiro , Arai Maki , Endo Shiori , Hirai Ryoji , Ikeda Koji , Kadota Satoki , Otsuka Yuki , Yamaguchi Takuhiro , Kawase Tetsuaki , Kobayashi Toshimitsu
Published: August 2019

Objectives/Hypothesis

To report the efficacy and safety of transtympanic plugging of the eustachian tube (ET) using a silicone plug (Kobayashi plug) for chronic patulous ET (PET).

Study Design

Prospective and multicenter trial conducted in which 30 PET patients were resistant to at least 6 months of conservative treatment.

Methods

The efficacy and safety of 28 and 27 patients, respectively, were analyzed. All patients fulfilled inclusion and exclusion criteria. The primary end point used the patulous eustachian tube handicap inventory‐10 (PHI‐10), and the secondary end point used ET function tests such as sonotubometry, tubo‐tympano‐aerodynamic‐graphy, and respiratory movement of the tympanic membrane and auscultation of voice sounds transmitted from the nose through the ET to the external auditory canal at 3months after surgery.

Results

PHI‐10 scores were 34.4 ± 4.2, 6.4 ± 9, and 5.7 ± 8.6 at screening, and 3 and 6 months after surgery. Twenty‐three cases (82.1%, 95% confidence interval: 63.1%–93.9%) were judged as successes. There were five cases (17.2%) of middle ear effusion, four cases (13.8%) of tympanic membrane perforation, and one case of tinnitus due to surgery to remove the plug. No severe or life‐threatening complications were found.

Conclusions

This study revealed the efficacy and safety of silicone plug insertion for severe PET patients.

Level of Evidence

2

Laryngoscope, 130:1304–1309, 2020
Variant analysis in Chinese families with hereditary hemorrhagic telangiectasia
Authors: Zhao Yali , Zhang Yuan , Wang Xiangdong , Zhang Luo
Published: August 2019

Background

Hereditary hemorrhagic telangiectasia (HHT) is a vascular dysplasia disorder characterized by epistaxis, mucocutaneous telangiectasias and arteriovenous malformations in internal organs. Recurrent epistaxis is the primary complaint in 90%‐96% of HHT patients and the other symptoms come with age. The aim of this study was to analyze HHT‐associated gene variant spectrum in Chinese HHT patients and to assess whether genetic testing could contribute to the early diagnosis.

Methodology/Principal

Thirty one HHT families including 62 individuals were recruited. Variants in the coding regions of four genes involved in HHT were amplified and analyzed using Sanger sequencing and multiplex ligation‐dependent probe amplification (MLPA).

Results

Twenty unique variants, including 8 novel variants were found in 24 of the 31 (77.4%) kindred. Diagnosis is confirmed for 7 possible individuals from 6 kindred. Thirteen ACVRL1 variants were detected from 17 isolated HHT families. Variants in ACVRL1 from 8/17 (47.1%) families were located in exon8. Seven ENG variants were found in 7 unrelated families throughout the coding region.

Conclusion

We conclude that ACVRL1 gene variant is 2.4 times more prevalent than that in ENG in Chinese individuals with HHT, and exon8 of the ACVRL1 gene may be a hotspot region. Genetic testing could contribute to early diagnosis for HHT.
SPECT/CT and fusion ultrasound to target the efferent groin lymph node for lymphatic surgery
Authors: Gentileschi Stefano , Albanese Roberta , Pino Valentina , Stefanizzi Gianluigi , Fragomeni Simona , Zagaria Luca , Ieria Francesco P. , Salgarello Marzia , Scambia Giovanni , Garganese Giorgia
Published: August 2019

Introduction

Pelvic lymphadenectomy (PL) causes changes to the inguinal lymph nodes with progressive loss of immune and lymphatic pump function. Efferent lymphatic vessel‐to‐venous anastomosis (ELVA) has been reported to address this problem. The aim of this report was to describe the feasibility of the SPECT/CT combined with ultrasound fusion imaging (UFI) to target the groin efferent lymph node (GELN) for ELVA.

Patients and Methods

Twelve patients with lower limb lymphedema after PL were scheduled for peripheric lymphaticovenular anastomosis (LVA) combined with ELVA. All‐patients were clinically ISL‐stage1, with good visualization of the inguinal lymph nodes at preoperative lymphoscintigraphy. The mean patient age was 55.4 years and the mean BMI was 25.5.The mean limb circumference (MLC) was calculated before surgery and 1 year after surgery. The LymQoL‐Leg questionnaire was administered before surgery and 6 months after surgery. Before surgery, the GELN was identified by SPECT/CT and its location was marked on the skin by UFI virtual navigation. Peripheric LVA sites were planned by ultrasound and indocyanine green (ICG) lymphography. Pre and postoperative MLC and LymQoL‐Leg scores were compared.

Results

In all‐patients, the SPECT/CT succeeded at detecting and targeting the GELN. In all‐patients, real‐time anatomical coregistration with US was feasible, and it was possible to mark on the groin skin the depth and position of the GELN on the skin at the groin. During surgery, in every patient, we found the GELN marked before surgery and performed ELVA. We also performed two or three peripheric LVAs in every patient. The mean value of MLC decreased (38.2 ± 2.13 cm vs. 36.33 ± 2.14 cm; p = .04) and the mean score of the LymQoL‐Leg questionnaire improved (9.3 ± 1.7 vs. 7.7 ± 1.1; p = .02).

Conclusion

SPECT/CT combined with UFI is feasible for the preoperative identification of GELN for ELVA.
Systematic assessment of multi‐echo dynamic susceptibility contrast MRI using a digital reference object
Authors: Stokes Ashley M. , Semmineh Natenael B. , Nespodzany Ashley , Bell Laura C. , Quarles C. Chad
Published: August 2019

Purpose

Brain tumor dynamic susceptibility contrast (DSC) MRI is adversely impacted by T1 and contrast agent leakage effects that result in inaccurate hemodynamic metrics. While multi‐echo acquisitions remove T1 leakage effects, there is no consensus on the optimal set of acquisition parameters. Using a computational approach, we systematically evaluated a wide range of acquisition strategies to determine the optimal multi‐echo DSC‐MRI perfusion protocol.

Methods

Using a population‐based DSC‐MRI digital reference object (DRO), we assessed the influence of preload dosing (no preload and full dose preload), field strength (1.5 and 3T), pulse sequence parameters (echo time, repetition time, and flip angle), and leakage correction on relative cerebral blood volume (rCBV) and flow (rCBF) accuracy. We also compared multi‐echo DSC‐MRI protocols with standard single‐echo protocols.

Results

Multi‐echo DSC‐MRI is highly consistent across all protocols, and multi‐echo rCBV (with or without use of a preload dose) had higher accuracy than single‐echo rCBV. Regression analysis showed that choice of repetition time and flip angle had minimal impact on multi‐echo rCBV and rCBV, indicating the potential for significant flexibility in acquisition parameters. The echo time combination had minimal impact on rCBV, though longer echo times should be avoided, particularly at higher field strengths. Leakage correction improved rCBV accuracy in all cases. Multi‐echo rCBF was less biased than single‐echo rCBF, although rCBF accuracy was reduced overall relative to rCBV.

Conclusions

Multi‐echo acquisitions were more robust than single‐echo, essentially decoupling both repetition time and flip angle from rCBV accuracy. Multi‐echo acquisitions obviate the need for preload dosing, although leakage correction to remove residual leakage effects remains compulsory for high rCBV accuracy.
Retrospective correction of head motion using measurements from an electromagnetic tracker
Authors: Afacan Onur , Wallace Tess E. , Warfield Simon K.
Published: August 2019

Purpose

To investigate the feasibility of using an electromagnetic (EM) tracker to estimate rigid body head motion parameters, and using these measurements to retrospectively reduce motion artifacts.

Theory and Methods

A clinically used MPRAGE sequence was modified to measure motion using the EM tracking system once per repetition time. A retrospective k‐space based motion correction algorithm that corrects for phase ramps (translation in image domain) and rotation of 3D k‐space (rotation in image domain) was developed, using the parameters recorded using an EM tracker. The accuracy of the EM tracker for the purpose of motion measurement and correction was tested in phantoms, volunteers, and pediatric patients.

Results

Position localization was accurate to the order of 200 microns compared with registration localization in a phantom study. The quality of reconstructed images was assessed by computing the root mean square error, the structural similarity metric and average edge strength. Image quality improved consistently when motion correction was applied in both volunteer scans with deliberate head motion and in pediatric patient scans. In patients, the average edge strength improved significantly with retrospective motion correction, compared with images with no correction applied.

Conclusions

EM tracking was effective in measuring head motion in the MRI scanner with high accuracy, and enabled retrospective reconstruction to improve image quality by reducing motion artifacts.
CEST MR‐Fingerprinting: Practical considerations and insights for acquisition schedule design and improved reconstruction
Authors: Perlman Or , Herz Kai , Zaiss Moritz , Cohen Ouri , Rosen Matthew S. , Farrar Christian T.
Published: August 2019

Purpose

To understand the influence of various acquisition parameters on the ability of CEST MR‐Fingerprinting (MRF) to discriminate different chemical exchange parameters and to provide tools for optimal acquisition schedule design and parameter map reconstruction.

Methods

Numerical simulations were conducted using a parallel computing implementation of the Bloch‐McConnell equations, examining the effect of TR, TE, flip‐angle, water and , saturation‐pulse duration, power, and frequency on the discrimination ability of CEST‐MRF. A modified Euclidean distance matching metric was evaluated and compared to traditional dot product matching. L‐Arginine phantoms of various concentrations and pH were scanned at 4.7T and the results compared to numerical findings.

Results

Simulations for dot product matching demonstrated that the optimal flip‐angle and saturation times are and 1100 ms, respectively. The optimal maximal saturation power was 3.4 μT for concentrated solutes with a slow exchange rate, and 5.2 μT for dilute solutes with medium‐to‐fast exchange rates. Using the Euclidean distance matching metric, much lower maximum saturation powers were required (1.6 and 2.4 μT, respectively), with a slightly longer saturation time (1500 ms) and flip‐angle. For both matching metrics, the discrimination ability increased with the repetition time. The experimental results were in agreement with simulations, demonstrating that more than a 50% reduction in scan‐time can be achieved by Euclidean distance‐based matching.

Conclusions

Optimization of the CEST‐MRF acquisition schedule is critical for obtaining the best exchange parameter accuracy. The use of Euclidean distance‐based matching of signal trajectories simultaneously improved the discrimination ability and reduced the scan time and maximal saturation power required.
Hospital food: When nurses' and ethnic minority patients' understanding of Islamic dietary needs differ
Authors: Alpers Lise‐Merete
Published: August 2019

Aim

The aim of this study was to investigate how medical unit nurses assess their knowledge about Muslim patients' dietary preferences and needs and Muslim patients' needs regarding food.

Design

Mixed‐method design.

Methods

Two‐part study. Part 1: Two focus group interviews and a survey answered by medical unit nurses. Part 2: In‐depth interviews with ten immigrant patients (eight Asians and two Africans). Hermeneutic analysis of qualitative data and SPSS were used for descriptive analysis of the quantitative data.

Results

The nurses' knowledge about acceptable and prohibited food within Islam appears to be simplistic and Muslim patients tended to be perceived as a homogenous group. Patients' distrust about the preparation and content of the food served may result in insufficient nutritional intake. Serving food that is acceptable to individual patients requires insight and is an essential part of culturally sensitive nursing care.
‘The hospital and everyday life are two worlds’: Patients’ and healthcare professionals’ experiences and perspectives on collaboration in the kidney transplantation process
Authors: Nielsen Charlotte , Agerskov Hanne , Bistrup Claus , Clemensen Jane
Published: August 2019

Aim

To explore patients’ and healthcare professionals’ experiences and perspectives on collaboration in the kidney transplantation process.

Design

A qualitative study with a phenomenological‐hermeneutic approach.

Method

Participant observation and interviews were conducted with 18 patients, together with a focus group with eight healthcare professionals from April 2016–January 2017. The data analysis was inspired by Ricoeur's theory.

Results

While patients acknowledged that the healthcare professionals were experts, they also requested an everyday life approach to treatment and care, because both professional knowledge and everyday life experiences were needed to manage everyday life. A contrast between patients’ experiences and healthcare professionals’ knowledge was identified, and the empowerment approach could be a way to combine the different perspectives.
Conducting surveys with multidisciplinary health care providers: Current challenges and creative approaches to sampling, recruitment, and data collection
Authors: Hutchinson Mary Katherine , Sutherland Melissa A.
Published: August 2019

Surveys represent one of the most common and useful ways to collect self‐reported data on a wide variety of topics and from a diversity of respondents, including health care providers (HCPs). Unfortunately, survey response rates have been declining for decades; surveys with HCPs often yield response rates of 40% or less. Another major challenge in surveys with HCPs arises from difficulties in identifying appropriate sampling frames. The lack of appropriate sampling frames is particularly problematic when trying to survey multiple types of HCPs or those who work in unusual practice settings or specialties. The purpose of this paper is to describe the current challenges to survey research with college HCPs who are members of multidisciplinary care teams, and propose alternative approaches to sampling and data collection. An exemplar is provided in which three different approaches to sampling, recruitment and data collection were undertaken with a multidisciplinary sample of college HCPs. The three approaches are compared in terms of response rates, costs, and sample characteristics. Differences were noted in effort, response rates, and sample characteristics. Respondents recruited from professional organization mailing lists were disproportionately from smaller, private college/universities, as compared with those recruited from colleges/universities selected from a U.S. Department of Education list. However, no differences in variables of interest were found between the three samples, reducing concerns of potential bias. Developing best practices for surveying multiple types of HCPs will become increasingly important as we seek to better understand current care processes and plan implementation studies to promote the adoption of practice recommendations.
Investigating the mechanical, morphological, and thermal behavior of PA‐6/SAN/MWCNT blends: Application of Taguchi experimental design
Authors: Shabani Ali , Babaei Amir , Zanjanijam Ali Reza , Ramezani Maryam , Haji Abdolrasouli Mehdi
Published: August 2019

This work presents the study of morphology, melting and crystallization characteristics, and mechanical properties of the PA‐6/SAN blends reinforced with multiwalled carbon nanotubes (MWCNTs). The Taguchi method was employed to design the experiments based on the three varying parameters (ie, blend composition, nanofiller content, and sequence of blending) to obtain the optimized mechanical properties of the nanocomposites. In addition, localization of nanotubes was studied in terms of thermodynamic and kinetic prospects. It was observed that, due to the preferential tendency for localization of the carbon nanotubes toward the PA‐6 matrix, mixing protocol had an important role in determining the performance of the nanocomposites. Incorporation of an optimum weight percent of the MWCNT provided a good dispersion of the nanotubes and also an appropriate morphology for the blend. According to the analysis based on the Taguchi method, the optimum mixing protocol, blend composition, and MWCNT loading were M2, 80/20, and 0.5 wt%, respectively.
Computation and modeling of microwave absorbing CuO/graphene nanocomposites
Authors: Akinay Yuksel , Kizilcay Abdullah O.
Published: August 2019

In this study, the microwave absorption properties of single‐ and double‐layer composites were investigated for experimental and numerical solution in the 8.2 to 12.4 GHz for different thickness (t
m) of composites. Herein, the single‐layer composites (R1: CuO and R2: CuO‐containing graphene nanoparticle [GNP]) and double‐layer composites that composed of R1 and R2 layers were fabricated. The first double‐layer composite labeled as D1 contains R1 as a matching layer and R2 as an absorbing layer and the second double‐layer composite labeled as D2 contains R2 as a matching layer and R1 as an absorbing layer. D1 and D2 produced composites were also designed numerically and denoted as M1 and M2, respectively. The measured and simulated reflection loss (R
L) of double‐layer composites shows similar performance, and it was observed that the microwave absorbers obtained with experimental studies can be modeled using computer design. The M2 double‐layer design based on 5 mm of the matching layer and 2 mm of the absorbing layer shows a minimum R
L value of −33.7 dB at 10.06 GHz and an absorption bandwidth of about 1.13 GHz below −10 dB compared to single‐layer composites.
The validity of the viscero‐abdominal disproportion ratio for type of surgical closure in all fetuses with an omphalocele
Authors: Peters Nina C.J. , Hijkoop Annelieke , Lechner Rosan L. , Eggink Alex J. , van Rosmalen Joost , Tibboel Dick , Wijnen René M.H. , IJsselstijn Hanneke , Cohen‐Overbeek Titia E.
Published: August 2019

What's already known about this topic?

In fetuses with an isolated omphalocele, the OC/AC ratio is less than 24 weeks; gestation is of predictive value for postnatal type of closure.

What does this study add?

The OC/AC ratio is predictive for type of surgical closure and survival in all fetuses with an omphalocele.

This report is the first concerning the trend of the OC/AC ratio throughout gestation.

The OC/AC ratio best predicts type of closure and survival in the third trimester of pregnancy.
Gender Differences in Outcomes after Traumatic Brain Injury among Service Members and Veterans
Authors: Cogan Alison M. , McCaughey Virginia K. , Scholten Joel
Published: August 2019

This scoping study describes the range of outcomes in traumatic brain injury (TBI) studies of military service members and veterans addressing gender differences. A secondary purpose is to identify differences in outcomes between male and female participants in such studies. We searched PubMed, CiNAHL, and PsycInfo databases for relevant articles. Two reviewers independently screened results. Of 822 unique titles and abstracts screened for eligibility, 55 full articles were reviewed, with 29 studies meeting full inclusion criteria. Twenty of the 29 included studies used retrospective designs and all but two used data collected from Veterans Affairs or Department of Defense health care settings. TBI was diagnosed by self‐report, screening, and evaluation procedures, and medical record documentation. Ten different outcome categories were identified among the included studies. In general, female service members and veterans have not been well represented in TBI outcomes research. Evidence suggests that female veterans with mild TBI (mTBI) report more neurobehavioral symptoms and use more outpatient services than male veterans. Studies also indicate that female veterans with TBI are more frequently diagnosed with depression. Additional research is essential to support precision treatment recommendations for female veterans with TBI, as women represent a growing proportion of the patients served by the Veterans Health Administration.

Level of Evidence

IV
Cobalt(II) phenoxy‐imine complexes in radical polymerization of vinyl acetate: The interplay of catalytic chain transfer and controlled/living radical polymerization
Authors: Chen Yi‐Hao , Chen Shih‐Ji , Li Jia‐Qi , Wu Zhenqiang , Lee Gene‐Hsiang , Liu Yi‐Hung , Cheng Wei‐Ting , Yeh Chen‐Yu , Peng Chi‐How
Published: August 2019

A series of cobalt(II) phenoxy‐imine complexes (CoII(FI)2) have been synthesized to mediate the radical polymerization of vinyl acetate (VAc) and methyl acrylate (MA) to evaluate the influence of chelating atoms and configuration to the control of polymerization. The VAc polymerizations showed the properties of controlled/living radical polymerization (C/LRP) with complexes 1a and 3a, but the catalytic chain transfer (CCT) behaviors with complexes 2a, 1b, 2b, and 3b. The control of VAc polymerization mediated by complex 1a could be improved by decreasing the reaction temperature to approach the molecular weights that not only linearly increased with conversions but also matched the theoretical values and relatively narrow molecular weight distributions. The catalytic chain transfer polymerizations (CCTP) mediated by complexes 2a, 1b, 2b, and 3b were characterized by Mayo plots and the polymer chain end double bonds were observed by 1H NMR spectra. The tendency toward C/LRP or CCTP in VAc polymerization mediated by CoII(FI)2 could be determined by the ligand structure. Cobalt complex coordinated by the ligand with more steric hindered and less electron‐donating substituents favored the controlled/living radical polymerization. In contrast, the efficiency of CCT process could be enhanced by less steric hindered, more electron‐donating ligands. The controlled/living radical polymerization of MA, however, could not be achieved by the mediation of these cobalt(II) phenoxy‐imine complexes. Associated with the results of polymerization mediated by other cobalt complexes, this study implied that the configuration and spin state of cobalt complexes were more critical than the chelating atoms to the control behavior of radical polymerization. © 2019 Wiley Periodicals, Inc. J. Polym. Sci. 2020, 58, 101–113
Synthesis of oligo(spiroketal)s by polycondensation of silyl ethers derived from naturally occurring myo‐inositol with 1,4‐cyclohexanedione
Authors: Sudo Atsushi , Yamasaki Tomoki , Yamashita Takuro , Ishida Dai
Published: August 2019

Oligo(spiroketal)s (OSKs) were synthesized from myo‐inositol, a naturally occurring cyclic compound bearing six hydroxyl groups. The successful synthesis of OSKs was achieved using silyl ethers 2 derived from 1,4‐di‐O‐alkylated myo‐inositol 1 as monomers, which underwent polycondensation with 1,4‐cyclohexanedione (CHD) at 0 °C in the presence of trimethylsilyl triflate as a catalyst. Because of the irreversible nature of the condensation reaction of silyl ethers with ketones, the resulting OSKs 7 had higher molecular weights than previously reported OSKs that were obtained by polycondensation of tetraols 1 with CHD, where backward hydrolysis of the ketal functions occurred. In addition, another series of OSKs, 8, were synthesized using silyl ethers 3 derived from 2,5‐di‐O‐alkylated myo‐inositol 6, which are more symmetric monomers than silyl ethers 2. Silyl ethers 3 underwent efficient polycondensation with CHD, whereas tetraol 6 did not, demonstrating that the derivation of such tetraols into the corresponding silyl ethers is a powerful strategy to access OSKs. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2407–2414
Investigating Chain Dynamics in Highly Crosslinked Polymers using Solid‐State 1H NMR Spectroscopy
Authors: Alam Todd M. , Jones Brad H.
Published: August 2019

Solid state 1H NMR line‐shape analysis and (double quantum) DQ 1H NMR experiments have been used to investigate the segmental and polymer chain dynamics as a function of temperature for a series of thermosetting epoxy resins produced using different diamine curing agents. In these thermosets, chemical crosslinks introduce topological constraints leading to residual stresses during curing. Materials containing a unique ferrocene‐based diamine (FcDA) curing agent were evaluated to address the role of the ferrocene fluxional process on the atomic‐level polymer dynamics. At temperatures above the glass transition temperature (Tg), the DQ 1H NMR experiments provided a measure of the relative effective crosslink and entanglement densities for these materials and revealed significant polymer chain dynamic heterogeneity in the FcDA‐cured thermosets. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 1143–1156
A derived Polymorphic Amplified Cleaved Sequence assay for detecting the Δ210 PPX2L codon deletion conferring target‐site resistance to protoporphyrinogen oxidase‐inhibiting herbicides
Authors: Kaundun Shiv S , Hutchings Sarah‐Jane , Marchegiani Elisabetta , Rauser Ruben , Jackson Lucy V
Published: August 2019

BACKGROUND

Resistance to protoporphyrinogen oxidase (PPO)‐inhibiting herbicides in Amaranthus rudis from corn/soybean production systems in the USA appears to be mainly due to a codon deletion at position 210 of the target PPX2L gene. In this study, we have developed a simple and cost‐effective derived Polymorphic Amplified Cleaved Sequenced (dPACS) marker for detecting this resistance‐causing deletion in A. rudis and other relevant weed species.

RESULTS

Ninety‐six plants from 16 diverse fomesafen‐sensitive and resistant A. rudis populations from Illinois and Iowa were used to establish the dPACS procedure. The assay requires forced mismatches in both the forward and reverse PCR primers and uses the restriction enzyme XcmI for the positive identification of wild type glycine residue at PPX2L codon position 210. The data from the dPACS method, using either leaf tissues or seeds as starting material, were completely correlated with direct Sanger sequencing results for samples that gave readable nucleotide peaks around codon 210 of PPX2L. Furthermore, the assay was directly transferable to all four other Amaranthus species tested, and to Ambrosia artemisiifolia using species‐specific primers.

CONCLUSION

The proposed assay will allow the rapid detection of the Δ210 codon deletion in the PPX2L gene and the timely development of management strategies for tackling growing resistance to PPO‐inhibiting herbicides in A. rudis and other broadleaf weed species. © 2019 Society of Chemical Industry
Chemical and growth traits of the peach tree may induce higher infestation rates of the green peach aphid, Myzus persicae (Sulzer)
Authors: Jordan Marie‐Odile , Sauge Marie‐Hélène , Vercambre Gilles
Published: August 2019

BACKGROUND

The green peach aphids, Myzus persicae, are a predominant pest in peach orchards as they can alter fruiting and shoot development for several years. This aphid developed resistance against pesticides. Among the alternative control strategies is the reduction of the trees' attractiveness to aphids. In order to identify the plant variables related to plant susceptibility, young peach trees were submitted to various supplies of water and nitrogen, and then artificially infested with aphids. Shoot development, plant water potential and aphid abundance were then monitored on a weekly basis. The apex concentrations in total N, amino acids, soluble sugars and polyphenols were determined at infestation start and infestation peak.

RESULTS

Until infestation peak, the thermal time requests for aphid development were independent of infestation severity. The aphid populations then collapsed more rapidly on the low infested shoots than on the high infested ones. Aphid abundances appeared to be positively related to shoot development (leaf expansion and secondary ramification), to shoot growth (stem length and diameter) and to apex concentrations in amino acids and non‐structural carbohydrates (NSC). Polyphenols had the opposite effect.

CONCLUSION

Peach susceptibility to aphids depends on shoot development and apex composition, and could be lowered by decreasing the water and nitrogen inputs. © 2019 Society of Chemical Industry
Improved synthetic route of exo‐16,17‐dihydro‐gibberellin A5‐13‐acetate and the bioactivity of its derivatives towards Arabidopsis thaliana
Authors: Tian Hao , He Yan , Liu Shaojin , Yang Zhikun , Wang Jine , Li Jianmin , Zhang Jianjun , Duan Liusheng , Li Zhaohu , Tan Weiming
Published: August 2019

BACKGROUND

The use of exo‐16,17‐dihydro‐gibberellin A5‐13‐acetate (DHGA5) in agriculture has been limited by its low synthetic yield. This study was aimed at optimizing the synthetic route of DHGA5, designing and synthesizing new derivatives with strong plant growth inhibitory activities.

RESULTS

Previous synthetic methods were replaced with a shorter, milder and faster reaction route with higher yield (76.3%) of DHGA5. Based on this novel route, a series of new derivatives were designed and synthesized using DHGA5 as a lead compound and characterized and evaluated for biological activities in Arabidopsis thaliana. Among the 15 tested derivatives, compound 14j showed a lower medium inhibition concentration (IC50, 73 μm) in Arabidopsis than that of DHGA5 (91 μm). Gibberellin deficient mutant assay further revealed that 14j had very different activities compared to DHGA5 as it specifically inhibits gibberellin biosynthetic pathways. In addition, 14j does not influence the interaction between gibberellin receptors (GID1) and the master growth repressor (RGA) based on yeast two‐hybrid assay.

CONCLUSION

The optimized synthetic route provides a promising method for large‐scale preparation of DHGA5. Our biological assays indicate that 14j likely acts on gibberellin signaling elements other than GID1. These results indicate that novel plant growth regulators can be developed. © 2019 Society of Chemical Industry
Influence of Dispersion Interactions on the Thermal Desorption of Nonplanar Polycyclic Aromatic Hydrocarbons on HOPG
Authors: Weippert Jürgen , Huber Philipp , Schulz Ayla , Amsharov Konstantin Y. , Böttcher Artur , Kappes Manfred M.
Published: August 2019

A combination of low energy ion beam deposition and mass resolved thermal desorption spectroscopy is applied to analyze the binding behavior of two nonplanar polycyclic aromatic hydrocarbons (PAHs) to highly oriented pyrolytic graphite (HOPG) surfaces—also concerning their lateral dispersion interactions. In particular, the fullerene precursor C60H30 (FPC) and rubrene C42H28 are studied. Due to their smaller contact areas, both molecules exhibit significantly weaker binding energies to the HOPG surface compared to planar PAHs of similar size: C60H30 is bound to the surface by 3.04 eV, which is 0.6 eV lower than for a fully planar homologue. For rubrene, an isolated molecule–substrate binding energy of 1.59 eV is found, which is about 1 eV less than that of the corresponding planar homologue hexabenzocoronene C42H18. In contrast to FPC, rubrene shows a significant (intermolecular) lateral dispersion contribution to the binding energy as the submonolayer coverage increases.
New approaches to postprocessing of multi‐model ensemble forecasts
Authors: Barnes Clair , Brierley Christopher M. , Chandler Richard E.
Published: August 2019

Ensemble weather forecasts often under‐represent uncertainty, leading to overconfidence in their predictions. Multi‐model forecasts combining several individual ensembles have been shown to display greater skill than single‐ensemble forecasts in predicting temperatures, but tend to retain some bias in their joint predictions. Established postprocessing techniques are able to correct bias and calibration issues in univariate forecasts, but are generally not designed to handle multivariate forecasts (of several variables or at several locations, say). We propose a flexible multivariate Bayesian postprocessing framework, based on a directed acyclic graph representing the relationships between the ensembles and the observed weather. The posterior forecast is inferred from available ensemble forecasts and an estimate of the shared discrepancy, obtained from a collection of past forecast–observation pairs. We also propose a novel approach to selecting an appropriate training set for estimation of the required correction, using synoptic‐scale analogues to obtain a regime‐dependent estimate of the adjustment. The proposed technique is applied to forecasts of surface temperature over the UK during the winter period from 2007 to 2013. Although the resulting parametric multivariate‐normal probabilistic forecasts are marginally less sharp than those of the leading competitor, they capture the spatial structure of the observations better than a correlation structure based on either the ensembles or climatology alone, and are robust to changes in the variables and spatial domain of the forecast, at a greatly reduced computational cost.
The prospects for increasing the horizontal resolution of the Aeolus horizontal line‐of‐sight wind profiles
Authors: Šavli Matic , de Kloe Jos , Marseille Gert‐Jan , Rennie Michael , Žagar Nedjeljka , Wedi Nils
Published: August 2019

This article evaluates the prospects for increasing the horizontal resolution of the Aeolus horizontal line‐of‐sight (HLOS) wind profiles at the expense of their accuracy. The evaluation is performed by combining a 10‐day atmosphere simulation by the ECMWF model at T3999 horizontal resolution with the CALIPSO observations of atmospheric composition as inputs to the Aeolus simulator. The validation shows that the ECMWF model represents the location and the vertical structure of the observed cloud systems well. At the nominal accumulation length of L ≈ 90 km (from the Aeolus measurement scale of ∼3 km), the Mie‐cloudy retrieval provides 1–4 times fewer observations than Rayleigh‐clear but the Mie‐cloudy HLOS winds have the highest quality with estimated error standard deviation of about 1 m/s in the troposphere and no bias. The experiments with reduced L reveal that neither the observation error standard deviation nor bias of the Mie‐cloudy winds are significantly affected when the accumulation length L varies in the range between 100 and 10 km. At the same time, the number of observations significantly increases as L reduces. This suggests that mesoscale NWP may profit from the Aeolus Mie‐cloudy HLOS profiles with the accumulation lengths as small as 10 km.
Complementors' engagement in an ecosystem: A study of publishers' e‐book offerings on Amazon Kindle
Authors: Wang Richard D. , Miller Cameron D.
Published: August 2019

Research Summary

In ecosystems, tensions between value creation and appropriation can arise when complementors form relationships with a partner that benefits from network effects. While creating value collectively, these relationships strengthen the network effects, which increase the partner's ability to appropriate value. We posit that complementors strategize their product offerings to benefit from the relationship with the partner while preserving bargaining power by keeping relationships with other partners as outside options. We examine book publishers' product portfolios in the Amazon Kindle e‐book and the printed book ecosystems. Our results illuminate specific product offering decisions by large publishers that are more protective of the printed book ecosystem and less conducive to Kindle's success. This research adds to the literature on interorganizational relationships, platform ecosystems, and managing digital innovations.

Managerial Summary

How do book publishers deal with Amazon? This paper compares book publishers' product offerings on Amazon's Kindle digital platform and in the physical print channel. We find that publishers offer high demand products as e‐books on Kindle to benefit from logistics savings. Yet, relative to small publishers, large publishers product decisions that support Kindle less, such as withholding some of their greatest revenue generating books. Such decisions could both limit Kindle's attractiveness to the consumers and preserve the economic viability of the print channel as an outside option. These findings improve our understanding of how companies can leverage their product portfolios to both benefit from digital technology efficiencies and maintain their bargaining power vis‐à‐vis digital platforms.
Post‐Deposition Vapor Annealing Enables Fabrication of 1 cm2 Lead‐Free Perovskite Solar Cells
Authors: Chowdhury Towhid H. , Kayesh Md. Emrul , Lee Jae-Joon , Matsushita Yoshitaka , Kazaoui Said , Islam Ashraful
Published: August 2019

Sn‐based perovskite solar cells (PSCs) are promising alternatives to replacing toxic Pb‐based PSCs, which have shown a rapid rise in photovoltaic applications in the past 1 year. However, the reported Sn‐based PSCs are often fabricated with a small aperture area (typically 0.02–0.1 cm2) because forming homogeneous pinhole‐free continuous films over a large surface area is still challenging. Herein, a post‐deposition vapor annealing (PDVA) process assisted by methylammonium chloride vapor is presented that enables the fabrication of stable, homogeneous pinhole‐free FASnI3 perovskite absorber films with low crystal defects and low surface recombination over a relatively large area up to 1.02 cm2. Inverted planar solar cells fabricated with a 1.02 cm2 aperture area show a maximum power conversion efficiency of 6.33% with high reproducibility and stability. The shelf‐lifetime stability test shows that the PSCs retain 90% of their performance for more than 1000 h when stored in a N2‐filled glove box and under dark conditions. The preliminary light‐soaking stability tests under continuous illumination and maximum power‐tracking conditions are relatively promising. This study marks an important step toward the up scaling of Sn‐based PSCs.