bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of Fluorinated Dialkyl Carbonates from Carbon Dioxide as a Carbonyl Source
Authors: Sugiyama Masafumi , Akiyama Midori , Nishiyama Kohei , Okazoe Takashi , Nozaki Kyoko
Published: February 2020

Fluorinated dialkyl carbonates (DACs), which serve as environmentally benign phosgene substitutes, were produced successfully from carbon dioxide either directly or indirectly. Nucleophilic addition of 2,2,2‐trifluoroethanol to carbon dioxide and subsequent reaction with 2,2,2‐trifluoroethyltriflate (3 a) afforded bis(2,2,2‐trifluoroethyl) carbonate (1) in up to 79 % yield. Additionally, carbonate 1 was obtained through the stoichiometric reaction of 3 a and cesium carbonate. Although bis(1,1,1,3,3,3‐hexafluoro‐2‐propyl) carbonate (4) was difficult to obtain by either of the above two methods, it could be synthesized through the transesterification of carbonate 1.
Lead transformational change, minimize resistance with 8‐step model
Authors: Radwan Ahmed
Published: February 2020

Change is hard, especially when it comes to higher education. Often, employees will resist change because they prefer their usual routines. The change agent — usually an academic leader — has to be academically and professionally prepared to lead such change. One framework for introducing change into higher education settings is John Kotter's 8‐Step Change Model.
Community college report outlines declining enrollment concerns, top priorities
Authors: Sutton Halley
Published: February 2020

A report looking at how community college staff, faculty, and administrative leaders are addressing national enrollment declines offers insights into challenges in increasing retention, enrollment, and graduation rates. Hanover Research administered a survey in the summer of 2019 and received responses from 275 faculty, staff, and administrators from community colleges. The findings were jointly published by Inside Higher Ed and Salesforce.
Effect of phase change material plates' arrangements on charging and discharging of energy storage in building air free cooling
Authors: Nada Sameh A. , Alshaer Walid G. , Saleh Ramy M.
Published: February 2020

Previous examinations of building air free cooling using phase change material (PCM) plates were numerically conducted for specific arrangements/configurations of PCMs plates. Experimental investigation for models validations and comparison between the different configurations of PCMs are the shortages of these studies. The present research experimentally investigates the effects of the PCM plate's arrangements on the thermal characteristics of the charging and discharging processes. Parallel and staggered arrangements of different spaces between the plates were tested. The effect of plates' arrangements on the discharging time and quantity of PCM needed to fulfill the required free cooling are also investigated. The results showed that (a) in parallel arrangement, the discharge time decreases with decreasing spaces between PCM plates; (b) the discharge time in staggered arrangement is longer than that of parallel arrangement by 63%; (c) putting PCM plates on large numbers of rows increases the discharge time; (d) in staggered arrangement, the discharge time increases with decreasing spacing between PCMs plates; (e) the needed quantity of PCMs plates in staggered arrangement is lower than that of parallel arrangement by about 67%; and (f) generally, staggered arrangement with low spaces between PCMs plates is the optimum arrangement for air free cooling as it has the longest discharge time.
Synchrotron Radiography for a Proton Exchange Membrane (PEM) Electrolyzer
Authors: Panchenko U. , Arlt T. , Manke I. , Müller M. , Stolten D. , Lehnert W.
Published: February 2020

In‐plane synchrotron radiography with a resolution of a few micrometers was applied to study transport processes within a Proton Exchange Membrane (PEM) electrolyzer cell. The degradation process of the catalyst layer, gas production with bubble formation at the catalyst layer and in the porous transport layer (PTL) was analyzed. From this, a new cell design was developed that allows for high X‐ray transmittances at the membrane plane in the in‐plane viewing direction. During the measurement, a bubble growth and movement was observed. Furthermore, a detachment of catalytic material from the catalyst layer was detected. Afterwards, a post mortem EDX analysis was conducted to determine the position of the catalyst particles. Despite Iridium being initially used as the anode catalyst and platinum as the cathode catalyst, the EDX measurement revealed Pt and Ir particles on both electrodes following cell operation.
Sturzprozesse ausgehend von Felsböschungen: Abschätzung der Reichweite mithilfe numerischer Modelle
Authors: Preh Alexander
Published: February 2020

Runout processes originating from rock slopes can be classified according to their process behaviour into rockfall, rock mass fall and rock avalanche. Their process behaviour is primarily determined by the volume of the detached rock mass, the degree of fragmentation of the moving mass and the morphology and nature of the runout path. The initial conditions of these processes depend on the initial failure mechanism. It is difficult to predict the runout and magnitudes of these types of rapid landslides since the complexity of the processes requires major simplifications in the calculation approaches. A good understanding of the process and clear mechanical model conceptions are therefore crucial in the development and choice of prediction models. The paper presents a classification of the runout processes originating from rock slopes on the basis of clearly defined mechanical models and provides an overview of the currently available models for prediction.
First occurrence of Tiaracrinus (Crinoidea, Zophocrinidae) in the Devonian of Iberia: Biostratigraphical, palaeoecological, and palaeogeographical implications
Authors: Domingos Rúben , Correia Pedro , Pinto De Jesus Ary , Legoinha Paulo , Callapez Pedro M.
Published: February 2020

Representatives of the crinoid genus Tiaracrinus are known from the Lochkovian to Eifelian (Early–Middle Devonian) of several countries, in Europe and North Africa. In this work, we describe the first occurrence of this taxon in the Devonian period of Iberian Massif (Iberia). Here, we report three specimens (two from the São Pedro da Cova region within Valongo anticline in northwestern Portugal and one from the Cantabrian Mountains in northern Spain), which are described to the type species Tiaracrinus quadrifrons. These new fossil findings provide new knowledge about the stratigraphic and geographic distribution of the genus Tiaracrinus and species T. quadrifrons. The co‐occurrence of T. quadrifrons in the Devonian outcrops of Valongo anticline also more precisely constrains the Devonian formations in age (Emsian–Eifelian) in that Portuguese region. In the palaeoecological and palaeoenvironmental context, this species coexisted with other crinoid species and representatives of several other groups of marine benthic invertebrates in a shallow water coral reef environment, with oxygenated substrates and regular salinity levels (mixoeuhaline environment). In addition, the presence of fine sediments with ripples suggests a low velocity current enough to reorient concentrations of tentaculite shells.
Development of the Uppsala model of internationalization process: From internationalization to evolution
Authors: Vahlne Jan‐Erik
Published: February 2020

Research Summary

I explain how the Uppsala model of the internationalization process progressed from explaining internationalization to explaining evolution. Initially, empirical findings led to the formulation of a model, later named the Uppsala model, driven by the interplay between experiential learning and commitments to expand the business into new foreign markets and deepen engagements in existing markets. Later, conceptions led to networks becoming a key ingredient in the model. As a result, globalization, geographical extensions and reconfigurations, and coordination changes were shown to follow the same pattern of learning and commitments as internationalization did. More recently, other dimensions in firms' evolution, such as R&D, and organizational and strategic change processes appear to follow similar processes of learning and commitments.

Managerial Summary

I explain how the Uppsala model of the internationalization process changed from explaining internationalization to explaining evolution. Superior profitability depends on not waiting until everything is known but rather managing under uncertainty, preferably acting before competitors do, which is risky, and this risk must be kept at an acceptable level. This is possible not only by learning from experience, as was proposed in the initial version of the model, but also from engaging with a network of partners and actors in the relevant field of knowledge, as a subsequent revision of the model acknowledged. The latest version of the model highlights the importance of evolution in the access and development of knowledge, with performance depending on both environmental change and managerial action.
Chiral nanoparticle‐induced amplification in optical activity of molecules with chiral centers
Authors: Yang Lin , Liu Junjun , Deng Junhong , Huang Zhifeng
Published: February 2020

Sensitive differentiation of an enantiomer from its mirror image (ie, enantiodifferentiation), a perennial challenge for pharmaceutical production and disease diagnosis, is technically limited by the weak optical activity (OA) of enantiomers, mainly due to their dimensional mismatch with light wavelengths in the ultraviolet (UV)‐visible region. Here we use silver chiral nanoparticles (Ag CNPs) with nominally sub‐5 nm helical pitch (P) to amplify the OA of (2′R, 3′R, 4′S)‐riboflavin‐5′‐phosphate sodium salts (RP), which have been found to indirectly affect metabolic processes, through the formation of an RP thin film (TF) covering a close‐packed array of Ag CNPs. The OA of the RP in the deep‐UV region can be amplified up to 80‐fold, ascribed to the aggregation of RP in the TFs and the interactions between RP and the atomically chiral lattices at the CNPs' surfaces. The former contribution, not associated with the chiral Ag topographies, plays a dominant role by thickening the RP TFs, so that the observed amplification has no enantioselective dependence on the chirality of the Ag CNPs. This study extends progress in the sensitive detection of bio‐enantiomers, which is highly desired for advanced bio‐detection in disease diagnosis and production of single‐enantiomer pharmaceuticals.

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Probing the bent bonds in cyclopropane systems for gas storage and separation process: A computational study
Authors: Wakchaure Padmaja D. , Ganguly Bishwajit
Published: February 2020

The hydrogen, carbon dioxide, and carbon monoxide gas adsorption and storage capacity of lithium‐decorated cyclopropane ring systems were examined with quantum chemical calculations at density functional theory, DFT M06‐2X functional using 6‐31G(d) and cc‐pVDZ basis sets. To examine the reliability of M06‐2X DFT functional, a few representative systems are also examined with complete basis set CBS‐QB3 method and CCSD‐aug‐cc‐pVTZ level of theory. The cyclopropane systems can bind to one Li+ ion; however, the corresponding the methylated systems can bind with two Li+ ions. The cyclopropane systems can adsorb six hydrogen molecules with an average binding energy of 3.8 kcal/mol. The binding free energy (ΔG) values suggest that the hydrogen adsorption process is feasible at 273.15 K. The calculation of desorption energies indicates the recyclable property of gas adsorbed complexes. The same number of CO2 and CO gas molecules can also be adsorbed with an average binding energy of −14.4 kcal/mol and −10.7 kcal/mol, respectively. The carbon dioxide showed ~3–4 kcal/mol better binding energy as compared to carbon monoxide and hence such designed systems can function as a potential candidate for the separation of these flue gas molecules. The nature of interactions in complexes was examined with atoms in molecules analysis revealed the electrostatic nature for the interaction of Li+ ion with cyclopropane rings. The chemical hardness and electrophilicity calculations showed that the gas adsorbed complexes are rigid and therefore robust as gas storage materials.
Interaction of triols with formaldehyde and acetone: Experimental and theoretical study
Authors: Sultanova Rimma , Borisevich Sophia , Raskil'dina Gulnara , Borisova Julianna , Baykova Irina , Spirikhin Leonid , Khursan Sergey , Zlotsky Simon
Published: February 2020

Experimental and theoretical aspects of the condensation of glycerol and its homologs (1,2,3‐ and 1,2,4‐butanetriols) with formaldehyde and acetone are studied under conditions of acid catalysis. Calculation of the thermodynamic parameters of the resulting products by the composite method CBS‐QB3 shows that the six‐membered heterocycles, the products of the interaction of triols with formaldehyde, are thermodynamically more stable than the five‐membered acetals, while the reaction of the same triols with acetone is preferable for the formation of the five‐membered acetals. This is due to the fact that the regioselectivity of the studied reactions is determined by the structural features and reactivity of the carbocations formed in a condensed medium during the course of the reaction. According to the theoretical data obtained experimentally, during the condensation of glycerol and 1,2,4‐butanetriol with formaldehyde in the most stable form of the six‐membered cyclic carbocation, intramolecular hydrogen bonding and anomeric stabilization due to the axially oriented hydroxyl group take place. As a result, cation 1b–1 is 1.2–1.6 kJ/mol more stable than its five‐membered isomers (1a–1 and 1b–2). It leads to the predominant formation of 1,3‐dioxane (3b). However, upon condensation of butanetriol‐1,2,3 with formaldehyde, the intermediate cation 4a–1 turns out to be significantly more stable than the other isomers due to the strong intramolecular hydrogen bond in the six‐membered ring with the participation of the hydroxyl group of the substituent and the hydroxyl group of the cationic center, leading to the predominant formation of the dioxolane 6a.
Potential diagnostic value of PD‐1 in peripheral blood mononuclear cells of postmenopausal osteoporosis patients
Authors: Cai Xiu‐Ping , Zhao Qing , Guo Zhao‐Di , Lin Shao‐Jun , Chen Zhi‐Xiang , Chen Min‐Yuan , Zheng Lei , Zhao Ke‐Wei
Published: February 2020

Background

Postmenopausal osteoporosis (PMOP) is an estrogen deficiency‐induced skeletal disorder. Bone mineral density (BMD) testing is the gold standard for diagnosing osteoporosis. However, its sensitivity for fracture risk assessment is low. Programmed cell death protein 1 (PD‐1) is a key immune checkpoint molecule implicated in the pathophysiology of bone remodeling, but its role in osteoporosis has not yet been explored. Thus, this study aimed to assess the expression and diagnostic utility of PD‐1 in PMOP.

Methods

A total of 56 patients with PMOP and 37 postmenopausal healthy controls (NC) were enrolled in the study. Peripheral blood mononuclear cells (PBMCs) were isolated by Ficoll density gradient centrifugation, and PD‐1 expression was measured by quantitative polymerase chain reaction (qPCR). Pearson's correlation test was performed to explore the associations between PD‐1 level and clinical variables, while receiver operating characteristic (ROC) curve analysis was used to evaluate the potential diagnostic value of PD‐1 in patients with PMOP.

Results

We found that PD‐1 level was significantly upregulated in the PBMCs of PMOP patients than those of NC (P = .016). PD‐1 expression was positively correlated with C‐reactive protein (CRP) levels. ROC curve analysis showed that PD‐1 had certain diagnostic value for PMOP (area under the curve = 0.65, standard error = 0.06, 95% confidence interval [0.53,0.76], P = .016), with a sensitivity and specificity of 44.64% and 81.08%, respectively.

Conclusion

Programmed cell death protein 1 is significantly upregulated in the PBMCs of PMOP patients and has certain diagnostic value for PMOP.
Ascending‐Dose Study of Controlled‐Release Ketamine Tablets in Healthy Volunteers: Pharmacokinetics, Pharmacodynamics, Safety, and Tolerability
Authors: Glue Paul , Medlicott Natalie J. , Surman Peter , Lam Fred , Hung Noelyn , Hung C. Tak
Published: February 2020

Parenteral ketamine has fast‐onset antidepressant and antianxiety effects; however, it causes dissociation, hypertension, and tachycardia shortly after dosing. Ketamine's antidepressant effects may be due to active metabolites rather than to ketamine itself. We hypothesized that oral controlled‐release ketamine tablets would improve safety and tolerability compared with injected ketamine by reducing peak ketamine exposures compared with dosing by injection. In this randomized, placebo‐controlled ascending‐dose study, ketamine doses of 60, 120, or 240 mg or matching placebo (single dose followed by every‐12‐hours dosing for 5 doses) were given to 24 healthy volunteers. Pharmacokinetics, pharmacodynamics (brain‐derived neurotropic factor), adverse events, and vital signs were assessed up to 72 hours. Drug release occurred over ∼10 hours, with most drug substance present as norketamine (∼90%). Area under the concentration‐time curve and peak concentration were dose proportional. Elimination half‐life was prolonged (7‐9 hours) compared with published data from immediate‐release oral formulations. There were no changes in blood pressure or heart rate after any dose. Mild dissociation was reported after 240 mg but not lower doses; mean dissociation ratings in this group were minimal (1‐2/76). There were no clinically significant changes in ECGs or safety laboratory tests at any time. Compared with injected ketamine, oral controlled‐release ketamine tablets did not increase blood pressure or heart rate, and only at doses of 240 mg was dissociation of mild intensity reported. Reducing and delaying ketamine peak concentration by oral dosing with controlled‐release ketamine tablets improve this drug's tolerability for patients with depression/anxiety.
Morphological characterization of Hypnaceae (Bryopsida, Hypnales): Investigating four genera from Western Himalayas by using LM and SEM techniques
Authors: Khan Aamir Shehzad , Ahmad Mushtaq , Zafar Muhammad , Athar Mohammad , Ozdemir Fethi Ahmet , Gilani Syed Aneel Ahmad , Sultana Shazia , Ahmad Shafiq , Butt Maryam Akram , Majeed Salman , Khan Shahzeb Ullah
Published: February 2020

The Hypnaceae is one of the largest and diversified family among the pleurocarpous mosses which consists of nearly 60 genera and 1,000 species around the world. In Pakistan, it is represented by 15 species and 8 genera. The current research article provides the detail morphological investigation of four different species (genera) of the family Hypnaceae that is, Gollania clarescens, Hypnum revolutum, Homomallium andoi, and Taxiphyllum taxirameum in the Western Himalayas, Pakistan. The research article reports the first SEM study of the leaf surfaces of the studied taxa, along with comprehensive morphological characters of the four species. The main objective of the research project is to present the comparative light and scanning electron microscopic study to discuss the morphology in detail because previously the family is just reported in different bryophyte checklists of the Western Himalayas. Based on results, morphological characters, micromorphological observations, qualitative and quantitative attributes, taxonomic keys for the studied taxa, distribution, and habitat are described. Stereoscope was used to analyze different qualitative characters, and light microscope was used to observe and measure the laminal and alar cells of the leaf. The SEM study reveals many important surface features like cell shape and cell wall. The laminal cells were mostly linear and elongated with thin cell walls. The specimens used for the SEM were air dried, so the laminal cells were somewhat constricted and concaved. The current study project will help to make the contribution in the taxonomy and morphology of this family.
Recent advances in parametric modeling of microwave components using combined neural network and transfer function
Authors: Feng Feng , Zhang Jianan , Zhang Wei , Zhao Zhihao , Jin Jing , Zhang Qi‐Jun
Published: February 2020

Parametric modeling of electromagnetic (EM) behaviors has become important for EM design optimizations of microwave components. This paper provides an overview of recent advances in parametric modeling of microwave components using combined neural network and transfer function (neuro‐TF). Transfer functions are used to represent the EM responses of passive components vs frequency. With the help of the transfer function, the nonlinearity of the neural network structure can be significantly decreased. We first introduce the neuro‐TF modeling approach in rational format. We also review the pole‐residue‐based neuro‐TF modeling technique. The orders of the pole‐residue transfer functions may vary over different regions of geometrical parameters. A pole‐residue tracking technique can be used to solve this order‐changing problem. As a further advancement, we discuss the sensitivity analysis‐based neuro‐TF modeling technique. The purpose is to increase the model accuracy by utilizing EM sensitivity information and to speed up the model development process by reducing the number of training data required for developing the model. After the modeling process, the trained model can be used to provide accurate and fast prediction of the EM responses w.r.t. the geometrical variables and can be subsequently used in the high‐level circuit and system design.
Connecting people to purpose builds a sustainable business model at Bark House
Authors: Collins Hilary , Saliba Cosette
Published: February 2020

At Bark House, a purpose‐driven, sustainability‐oriented small and medium‐size enterprise (SME) based in North Carolina, a symbiotic relationship between the firm and its stakeholders has led to the development of a resilient business model that has generated hundreds of green‐collar jobs. Data collected through semi‐structured interviews show that by proactively engaging with stakeholders, the firm has been able to change market perceptions and behavior, and to refine its core operations to become more sustainable. In addition, the stakeholders' belief in the authenticity of the organization's commitment to environmental responsibility influences the way employees feel about themselves and how they behave with others. By putting environmental and societal concerns before profits, the firm generates customer loyalty that enables it to survive economic downturns and offers the promise of long‐term success.
Perceptions of Nigerian final year undergraduate students of the adequacy of the pharmacy curriculum for mental health care
Authors: Saka Sule A. , Akanbi Oluwaseyi S. , Eze Uchenna I. H.
Published: February 2020

Background

There is growing concern about the adequacy of undergraduate curricula in schools of pharmacy worldwide regarding mental health. In Nigeria, both Bachelor and Doctor of Pharmacy degrees (BPharm and PharmD, respectively) are offered, but little is known about the scope of mental health care in either curriculum.

Aim

This study evaluated the perceptions of final year undergraduate students regarding the adequacy of the pharmacy curriculum in mental health care and their preparedness for a career in the field.

Methods

A pretested 33‐item questionnaire was administered to 950 (BPharm, n = 858; PharmD, n = 92) consecutively selected final year undergraduate students in the 19 accredited schools of pharmacy in Nigeria who had undergone experiential learning in teaching hospitals and community pharmacies and registered for the 2017–18 academic year.

Results

Most respondents (618/950; 65.1%) had no explicit learning on common mental disorders at the time of the study, and this did not differ significantly between the BPharm and PharmD respondents (p = 0.66). Most respondents (763/950; 80.3%) strongly disagreed or disagreed with the assertion that ‘the curriculum exposes students to real‐life mental health practice’. Furthermore, of the 932 that responded to the assertion that ‘pharmacy undergraduate curriculum prepares one adequately to practice mental health pharmacy’ 613 (65.8%) strongly disagreed or disagreed, with no significant difference between the PharmD and BPharm groups (p = 0.085). The respondents (460/950; 48.4%) would not specialise in mental health pharmacy, 38.0% (175/460) because they felt unprepared in terms of skills.

Conclusion

The respondents perceived the pharmacy curriculum as inadequate for mental health care and considered this inadequacy a hindrance towards its practice in Nigeria.
Process design kit and design automation for flexible hybrid electronics
Authors: Huang Tsung‐Ching , Lei Ting , Shao Leilai , Sivapurapu Sridhar , Swaminathan Madhavan , Bao Zhenan , Cheng Kwang‐Ting , Beausoleil Raymond
Published: February 2020

High‐performance and low‐cost flexible hybrid electronics (FHE) are desirable for applications such as Internet of Things (IoT), wearable electronics, and flexible displays. However, design toolkit, design methodology, and compact models that play an essential role in designing complex FHE circuits and systems are still missing today. To fill this gap, here we report (a) the process design kit (PDK) dedicated to electronic design automation for FHE circuits and systems and (b) solution process–proven intellectual property (IP) blocks, which serves as a stepping stone for designing large‐scale flexible thin‐film transistor (TFT) circuits. The proposed FHE‐PDK is made compatible with modern electronics design tools for users to design, simulate, and verify physical design of flexible hybrid systems.
Prediction of vestibular schwannoma recurrence using artificial neural network
Authors: Abouzari Mehdi , Goshtasbi Khodayar , Sarna Brooke , Khosravi Pooya , Reutershan Trevor , Mostaghni Navid , Lin Harrison W. , Djalilian Hamid R.
Published: February 2020

Objectives

To compare two statistical models, namely logistic regression and artificial neural network (ANN), in prediction of vestibular schwannoma (VS) recurrence.

Methods

Seven hundred eighty‐nine patients with VS diagnosis completed an online survey. Potential predictors for recurrence were derived from univariate analysis by reaching the cut off P value of .05. Those nine potential predictors were years since treatment, surgeon's specialty, resection amount, and having incomplete eye closure, dry eye, double vision, facial pain, seizure, and voice/swallowing problem as a complication following treatment. Multivariate binary logistic regression model was compared with a four‐layer 9‐5‐10‐1 feedforward backpropagation ANN for prediction of recurrence.

Results

The overall recurrence rate was 14.5%. Significant predictors of recurrence in the regression model were years since treatment and resection amount (both P < .001). The regression model did not show an acceptable performance (area under the curve [AUC] = 0.64; P = .27). The regression model's sensitivity and specificity were 44% and 69%, respectively and correctly classified 56% of cases. The ANN showed a superior performance compared to the regression model (AUC = 0.79; P = .001) with higher sensitivity (61%) and specificity (81%), and correctly classified 70% of cases.

Conclusion

The constructed ANN model was superior to logistic regression in predicting patient‐answered VS recurrence in an anonymous survey with higher sensitivity and specificity. Since artificial intelligence tools such as neural networks can have higher predictive abilities compared to logistic regression models, continuous investigation into their utility as complementary clinical tools in predicting certain surgical outcomes is warranted.
Hippocampus segmentation on noncontrast CT using deep learning
Authors: Porter Evan , Fuentes Patricia , Siddiqui Zaid , Thompson Andrew , Levitin Ronald , Solis David , Myziuk Nick , Guerrero Thomas
Published: February 2020

Purpose

Accurate segmentation of the hippocampus for hippocampal avoidance whole‐brain radiotherapy currently requires high‐resolution magnetic resonance imaging (MRI) in addition to neuroanatomic expertise for manual segmentation. Removing the need for MR images to identify the hippocampus would reduce planning complexity, the need for a treatment planning MR imaging session, potential uncertainties associated with MRI‐computed tomography (CT) image registration, and cost. Three‐dimensional (3D) deep convolutional network models have the potential to automate hippocampal segmentation. In this study, we investigate the accuracy and reliability of hippocampal segmentation by automated deep learning models from CT alone and compare the accuracy to experts using MRI fusion.

Methods

Retrospectively, 390 Gamma Knife patients with high‐resolution CT and MR images were collected. Following the RTOG 0933 guidelines, images were rigidly fused, and a neuroanatomic expert contoured the hippocampus on the MR, then transferred the contours to CT. Using a calculated cranial centroid, the image volumes were cropped to 200 × 200 × 35 voxels, which were used to train four models, including our proposed Attention‐Gated 3D ResNet (AG‐3D ResNet). These models were then compared with results from a nested tenfold validation. From the predicted test set volumes, we calculated the 100% Hausdorff distance (HD). Acceptability was assessed using the RTOG 0933 protocol criteria, and contours were considered passing with HD ≤ 7 mm.

Results

The bilateral hippocampus passing rate across all 90 models trained in the nested cross‐fold validation was 80.2% for AG‐3D ResNet, which performs with a comparable pass rate (P = 0.3345) to physicians during centralized review for the RTOG 0933 Phase II clinical trial.

Conclusions

Our proposed AG‐3D ResNet's segmentation of the hippocampus from noncontrast CT images alone are comparable to those obtained by participating physicians from the RTOG 0933 Phase II clinical trial.
Multi‐spin echo T2 relaxation imaging with compressed sensing (METRICS) for rapid myelin water imaging
Authors: Dvorak Adam V. , Wiggermann Vanessa , Gilbert Guillaume , Vavasour Irene M. , MacMillan Erin L. , Barlow Laura , Wiley Neale , Kozlowski Piotr , MacKay Alex L. , Rauscher Alexander , Kolind Shannon H.
Published: February 2020

Purpose

Myelin water imaging (MWI) provides a valuable biomarker for myelin, but clinical application has been restricted by long acquisition times. Accelerating the standard multi‐echo T2 acquisition with gradient echoes (GRASE) or by 2D multi‐slice data collection results in image blurring, contrast changes, and other issues. Compressed sensing (CS) can vastly accelerate conventional MRI. In this work, we assessed the use of CS for in vivo human MWI, using a 3D multi spin‐echo sequence.

Methods

We implemented multi‐echo T2 relaxation imaging with compressed sensing (METRICS) and METRICS with partial Fourier acceleration (METRICS‐PF). Scan‐rescan data were acquired from 12 healthy controls for assessment of repeatability. MWI data were acquired for METRICS in 9 m:58 s and for METRICS‐PF in 7 m:25 s, both with 1.5 × 2 × 3 mm3 voxels, 56 echoes, 7 ms ΔTE, and 240 × 240 × 170 mm3 FOV. METRICS was compared with a novel multi‐echo spin‐echo gold‐standard (MSE‐GS) MWI acquisition, acquired for a single additional subject in 2 h:2 m:40 s.

Results

METRICS/METRICS‐PF myelin water fraction had mean: repeatability coefficient 1.5/1.1, coefficient of variation 6.2/4.5%, and intra‐class correlation coefficient 0.79/0.84. Repeatability metrics comparing METRICS with METRICS‐PF were similar, and both sequences agreed with reference values from literature. METRICS images and quantitative maps showed excellent qualitative agreement with those of MSE‐GS.

Conclusion

METRICS and METRICS‐PF provided highly repeatable MWI data without the inherent disadvantages of GRASE or 2D multi‐slice acquisition. CS acceleration allows MWI data to be acquired rapidly with larger FOV, higher estimated SNR, more isotropic voxels and more echoes than with previous techniques. The approach introduced here generalizes to any multi‐component T2 mapping application.
Differentiating the Sodium‐Glucose Cotransporter 1 Inhibition Capacity of Canagliflozin vs. Dapagliflozin and Empagliflozin Using Quantitative Systems Pharmacology Modeling
Authors: Sokolov Victor , Yakovleva Tatiana , Chu Lulu , Tang Weifeng , Greasley Peter J. , Johansson Susanne , Peskov Kirill , Helmlinger Gabriel , Boulton David W. , Penland Robert C.
Published: February 2020

The aim of this research was to differentiate dapagliflozin, empagliflozin, and canagliflozin based on their capacity to inhibit sodium‐glucose cotransporter (SGLT) 1 and 2 in patients with type 2 diabetes using a previously developed quantitative systems pharmacology model of renal glucose filtration, reabsorption, and excretion. The analysis was based on pooled, mean study‐level data on 24‐hour urinary glucose excretion, average daily plasma glucose, and estimated glomerular filtration rate collected from phase I and II clinical trials of SGLT2 inhibitors. Variations in filtered glucose across clinical studies were shown to drive the apparent differences in the glucosuria dose–response relationships among the gliflozins. A normalized dose–response analysis demonstrated similarity of dapagliflozin and empagliflozin, but not canagliflozin. At approved doses, SGLT1 inhibition by canagliflozin but not dapagliflozin or empagliflozin contributed to ~ 10% of daily urinary glucose excretion.
Magneto‐optical specifications of Rosen‐Morse quantum dot with screw dislocation
Authors: Bahar Mustafa Kemal , Ungan Fatih
Published: February 2020

This is the first study to consider a quantum dot with screw dislocation that has Rosen‐Morse (RM) confinement potential, generated by a GaAs/GaAlAs heterostructure. An external magnetic field and Aharonov‐Bohm (AB) flux field were also applied on RM quantum dot (RMQD) in order to stave the effects of a screw dislocation defect. The combined effect of the screw dislocation defect, the external magnetic field, and AB flux field on the total refractive index changes (TRICs) and the total absorption coefficients (TACs) of RMQD are thus investigated. Cylindrical coordinates are used due to the direction of application of the torsion and the external fields, as well as due to the structure's symmetry. The effective mass approximation and tridiagonal matrix methods are used in order to obtain the subband energy spectra and electronic wave functions of RMQD. The nonlinear optical specifications of RMQD are checked using compact‐density‐matrix formalism within the framework of the iterative method. Reviews without screw dislocation are also carried out in order to be able to clarify the effects of a screw dislocation defect on the optical properties, and then, both cases are deliberated. This study is the first attempt to analyze the AB flux field for RMQD without screw dislocation. In the present study, the influences of a screw dislocation defect on RMQD's TRICs and TACs are probed by considering different values of the external magnetic field and AB flux field, and the ranges of corresponding parameters on the optimum of the structure are specified. Moreover, the study also elucidates how to rule out the effects of screw dislocation on optical specifications by means of the external fields. Despite a certain screw dislocation, the frequency range is determined where the structure behaves as if it is perfect (namely, without screw dislocation) for its optimum, which in turn is crucial for experimental applications.
Structural characterization and discrimination of Paris polyphylla var. yunnanensis by a molecular networking strategy coupled with ultra‐high‐performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry
Authors: Wang Yumei , Fan Qian , Xiang Jun , Huang Haibo , Chen Sheng , Liu Bairu , Wu Aizhi , Zhang Cuixian , Rong Li
Published: February 2020

Rationale

Paris polyphylla var. yunnanensis (Franch) Hand Mazz (PPY) is a traditional Chinese medicine with antitumor, antibacterial, hemostatic, and anthelmintic activities. Identification of the chemical composition in PPY is helpful to discover its active ingredients and can be used to establish its quality control protocols.

Methods

The composition of PPY was identified using ultra‐high‐performance liquid chromatography combined with quadrupole time‐of‐flight mass spectrometry (UHPLC/QTOF‐MS/MS) coupled with a molecular networking strategy. First, the UHPLC/QTOF‐MS/MS approach was optimized for chemical compound profiling. Then, the MS data were processed using PeakView™ combined with an in‐house database to quickly characterize the secondary metabolites. Finally, molecular networking excavated new molecular weights to discover unknown or trace natural products based on the characteristics of each cluster.

Results

A total of 222 compounds, including 77 isospirostanols, 2 spirostanols, 19 furostanols, 10 pseudospirostanols, 6 cholesterols, 10 C21 steroids, 5 insect metamorphosis hormones, 3 plant sterols, 6 five‐ring triterpenoids, 4 flavonoids, 8 fatty acids, 2 phenylpropanoids, and 8 other compounds, were characterized in PPY by comparing their main fragmentation characteristics and pathways with the literature data, and 62 of them, 54 steroidals and 8 phenylpropanoids, were discovered or tentatively identified for the first time.

Conclusions

This study extended the application of a molecular networking strategy to traditional herbal medicines and developed a molecular networking based screening approach with a significant increase in efficiency for the discovery and identification of trace novel natural products.
Improving Reading Instruction and Students’ Reading Skills in the Early Grades: Evidence From a Randomized Evaluation in Haiti
Authors: Guzmán Juan Carlos , Schuenke-Lucien Kate , D’Agostino Anthony J. , Berends Mark , Elliot Andrew J.
Published: February 2020

In Haiti, 49% of students cannot read a single word in Creole by the time they start grade 3, which is reflective of a broader learning crisis in low‐income and fragile contexts. Read to Learn, an early‐grade literacy intervention, was implemented and evaluated from fall 2014 through spring 2016 with the aim of improving students’ reading skills. Students were given learning materials in their mother tongue, teachers were provided with training and instructional coaching, and various supports for program implementation were established. In a randomized evaluation, the authors assessed students’ reading skills at the beginning of grade 1 and at the end of grades 1 and 2 in treatment and control schools. The authors estimated the impact of the program at the end of grades 1 and 2 with a hierarchical linear model and found positive effects on emergent reading skills and oral reading fluency, with effect sizes ranging between 0.19 and 0.79. The results of this study are an important contribution to knowledge about what works to improve literacy outcomes for students in Haiti and other fragile contexts.
Ertüchtigung der Rheinbrücke Maxau – Teil 2
Authors: Katzik Walter , Scherer Mathias , Maier Dietmar H. , Würfel Till
Published: February 2020

Aufgrund von Ermüdungsschäden an der orthotropen Fahrbahn der Rheinbrücke Maxau wurde eine Ertüchtigung der Fahrbahn erforderlich. Diese wird durch das Aufbringen einer Aufbetonplatte aus hochfestem Beton realisiert. Die Bauweise wurde bereits mehrfach durch Anwendungen im Ausland und begleitende wissenschaftliche Untersuchungen erprobt. In Deutschland stellt die Fahrbahnertüchtigung der Maxauer Brücke die erste Anwendung auf einer großen Stahlbrücke dar. Im Vorfeld wurden hierzu Erfahrungen an einem vorgezogenen Pilotprojekt gesammelt. Die Herstellung einer Probeplatte ist ein wichtiges Instrument der Qualitätssicherung im Projekt. Die Bauausführung wird detailliert beschrieben. Abschließend wird auf das begleitende Monitoring und die Umsetzung der Öffentlichkeitsbeteiligung eingegangen. Nach der erfolgreichen Durchführung der Maßnahme ist künftig auch in Deutschland mit einer breiteren Anwendung dieser Ertüchtigungsmethode zu rechnen.
Dielectric strength of electric contacts after short‐duration arc in a hybrid DC circuit breaker
Authors: Nakayama Ryo , Ou Chomrong , Zen Shungo , Yasuoka Koichi
Published: February 2020

A hybrid direct current circuit breaker consisting of electrical contacts connected in parallel with a silicon carbide metal oxide semiconductor field‐effect transistor semiconductor device is capable of operating with low energy loss and high short‐circuit tolerance. It features a short‐duration arc discharge during current commutation; however, how the arc affects the dielectric strength between the contacts is not yet clear. This study conducts a quantitative evaluation of the dielectric strength after a short‐duration arc commutation. It is shown that the dielectric strength decreases after the arc commutation, and the breakdown electric field decreases as the arc duration increases. These results suggest that the existence of metal vapor and an increase in contact erosion caused by the commutation arc lower the dielectric strength of the electric contacts, in addition to the known effects of temperature rise of the contact surface and the air between contacts. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Ionenstrahlen zur Analyse von Wasserstoff in Festkörpern
Authors: Foest Rüdiger , Schmidt Martin , Kruth Angela
Published: February 2020

Ion beams for analysis of hydrogen in solids

Hydrogen is an important carrier of energy and, in the context of the growing request for renewable energy sources, a candidate for energy storage. Scientific questions relating to the study of the hydrogen of materials arise, on the one hand, from the interaction of hydrogen with the surrounding solid state material and, on the other hand, from the use of solids as a direct storage medium. Ion beam methods have proved suitable for this purpose. The methods secondary ion mass spectrometry (SIMS), elastic recoil detection analysis (ERD) and nuclear reaction analysis (NRA) are portrayed. Examples illustrate the techniques, applications for depth analysis are described and the sensitivity of the methods is given.
Excess enthalpy of mixing of mineral solid solutions derived from density-functional calculations
Authors: Benisek Artur , Dachs Edgar
Published: February 2020

Calculations using the density-functional theory (DFT) in combination with the single defect method were carried out to determine the heat of mixing behaviour of mineral solid solution phases. The accuracy of this method was tested on the halite–sylvite (NaCl–KCl) binary, pyrope–grossular garnets (Mg3Al2Si3O12–Ca3Al2Si3O12), MgO–CaO (halite structure) binary, and on Al/Si ordered alkali feldspars (NaAlSi3O8–KAlSi3O8); as members for coupled substitutions, the diopside–jadeite pyroxenes (CaMgSi2O6–NaAlSi2O6) and diopside–CaTs pyroxenes (CaMgSi2O6–CaAlAlSiO6) were chosen for testing and, as an application, the heat of mixing of the tremolite–glaucophane amphiboles (Ca2Mg5Si8O22(OH)2–Na2Mg3Al2Si8O22(OH)2) was computed. Six of these binaries were selected because of their experimentally well-known thermodynamic mixing behaviours. The comparison of the calculated heat of mixing data with calorimetric data showed good agreement for halite–sylvite, pyrope–grossular, and diopside–jadeite binaries and small differences for the Al/Si ordered alkali feldspar solid solution. In the case of the diopside–CaTs binary, the situation is more complex because CaTs is an endmember with disordered cation distributions. Good agreement with the experimental data could be, however, achieved assuming a reasonable disordered state. The calculated data for the Al/Si ordered alkali feldspars were applied to phase equilibrium calculations, i.e. calculating the Al/Si ordered alkali feldspar solvus. This solvus was then compared to the experimentally determined solvus finding good agreement. The solvus of the MgO–CaO binary was also constructed from DFT-based data and compared to the experimentally determined solvus, and the two were also in good agreement. Another application was the determination of the solvus in tremolite–glaucophane amphiboles (Ca2Mg5Si8O22(OH)2–Na2Mg3Al2Si8O22(OH)2). It was compared to solvi based on coexisting amphiboles found in eclogites and phase equilibrium experiments.
Translating Theory into Practice: Lessons Learned from Developing a Program Model to Foster Resiliency in Expectant and Parenting Youth
Authors: Pressfield Lissa , Campa Mary , Ramstrom Karen , Kabadi Sangi , Lopez Catherine
Published: February 2020

Purpose

This paper describes the approach used to develop the Adolescent Family Life Program (AFLP) Positive Youth Development (PYD) Model within the structure of an existing state government-run program.

Description

The California Department of Public Health, Maternal, Child and Adolescent Health (CDPH/MCAH) Division undertook an innovative approach to develop a program model to help expectant and parenting youth build resilience. CDPH/MCAH started by assessing existing program efforts and theory to develop and test new strategies in the field, structure a program model, and build toward broader expansion and sustainability. CDPH/MCAH engaged local organizations from across the state, their staff and enrolled youth, experts, and evaluators in an iterative program development process to standardize an effective model that could be replicated and evaluated.

Assessment

Key lessons for program developers and administrators are to ensure adequate staffing with diverse expertise related to the topic and content to support the multiple components of program development and implementation, evaluation, and training; identify the guiding theory and framework early and link them with clearly articulated core components to ensure the final model reflects the intended purpose and is structured to support implementation; engage implementation staff on the ground and focus early and often on processes for supporting people through change.

Conclusion

The lessons learned can guide others working with existing programs to develop standardized program models or translate new science and theory into practice.
How Many “Nones” Are There? Explaining the Discrepancies in Survey Estimates
Authors: Burge Ryan P.
Published: February 2020

While there has been a great deal of media focus recently on the rise of those without religious affiliation (also known as the “nones”), there is an underlying issue facing this line of research: different surveys come to completely different conclusions about how many nones actually exist in the United States. Using the General Social Survey (GSS) and the Cooperative Congressional Election Study (CCES) this work details how each of these instruments measures religious affiliation in a different manner and how that results in an estimate of the nones that diverges by over 8% points in 2018. Statistical analysis reveals that the GSS has a much higher share of Protestants who never attend church than that found in the CCES. In addition, the CCES Protestant subsample is more Republican, while the nones in the GSS are more to the left of the political spectrum than the nones in the CCES. Some advice and caution is offered to researchers who are interested in studying the religiously unaffiliated in these two surveys.