bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved contrast and noise of megavoltage computed tomography (MVCT) through cycle‐consistent generative machine learning
Authors: Vinas Luciano , Scholey Jessica , Descovich Martina , Kearney Vasant , Sudhyadhom Atchar 
Published: November 2020

PurposeMegavoltage computed tomography (MVCT) has been implemented on many radiation therapy treatment machines as a tomographic imaging modality that allows for three‐dimensional visualization and localization of patient anatomy. Yet MVCT images exhibit lower contrast and greater noise than its kilovoltage CT (kVCT) counterpart. In this work, we sought to improve these disadvantages of MVCT images through an image‐to‐image‐based machine learning transformation of MVCT and kVCT images. We demonstrated that by learning the style of kVCT images, MVCT images can be converted into high‐quality synthetic kVCT (skVCT) images with higher contrast and lower noise, when compared to the original MVCT.MethodsKilovoltage CT and MVCT images of 120 head and neck (H&N) cancer patients treated on an Accuray TomoHD system were retrospectively analyzed in this study. A cycle‐consistent generative adversarial network (CycleGAN) machine learning, a variant of the generative adversarial network (GAN), was used to learn Hounsfield Unit (HU) transformations from MVCT to kVCT images, creating skVCT images. A formal mathematical proof is given describing the interplay between function sensitivity and input noise and how it applies to the error variance of a high‐capacity function trained with noisy input data. Finally, we show how skVCT shares distributional similarity to kVCT for various macro‐structures found in the body.ResultsSignal‐to‐noise ratio (SNR) and contrast‐to‐noise ratio (CNR) were improved in skVCT images relative to the original MVCT images and were consistent with kVCT images. Specifically, skVCT CNR for muscle‐fat, bone‐fat, and bone‐muscle improved to 14.8 ± 0.4, 122.7 ± 22.6, and 107.9 ± 22.4 compared with 1.6 ± 0.3, 7.6 ± 1.9, and 6.0 ± 1.7, respectively, in the original MVCT images and was more consistent with kVCT CNR values of 15.2 ± 0.8, 124.9 ± 27.0, and 109.7 ± 26.5, respectively. Noise was significantly reduced in skVCT images with SNR values improving by roughly an order of magnitude and consistent with kVCT SNR values. Axial slice mean (S‐ME) and mean absolute error (S‐MAE) agreement between kVCT and MVCT/skVCT improved, on average, from −16.0 and 109.1 HU to 8.4 and 76.9 HU, respectively.ConclusionsA kVCT‐like qualitative aid was generated from input MVCT data through a CycleGAN instance. This qualitative aid, skVCT, was robust toward embedded metallic material, dramatically improves HU alignment from MVCT, and appears perceptually similar to kVCT with SNR and CNR values equivalent to that of kVCT images.
Facilitators and barriers to the provision of type 1 diabetes inpatient care: An interpretive phenomenological analysis
Authors: Nikitara Monica , Constantinou Costas S , Andreou Eleni , Latzourakis Evangelos , Diomidous Marianna 
Published: November 2020

AbstractAimThe aim and objective of this study was to understand how non‐specialized nurses understand the possible barriers and facilitators of inpatient care for type 1 diabetes.DesignAn interpretative phenomenology approach was conducted.MethodsThe sample consisted of non‐specialized nurses (N = 24) working in medical, surgical and nephrology wards in the state hospitals in Cyprus. The data were collected during 2016‐2018 from one focus group with nurses (N = 6) and individual semi‐structured interviews with nurses (N = 18) conducted. The Standards for Reporting Qualitative Research checklist used to ensure the quality of the study.ResultsIt is evident from the study findings that nurses experience several barriers in diabetes inpatient care reported which are of great concern since this could have adverse effects on patients' outcomes. Only one facilitator has been reported by few nurses.
Interface engineering of ultrathin Cu(In,Ga)Se2 solar cells on reflective back contacts
Authors: Gouillart Louis , Cattoni Andrea , Chen Wei‐Chao , Goffard Julie , Riekehr Lars , Keller Jan , Jubault Marie , Naghavi Negar , Edoff Marika , Collin Stéphane 
Published: November 2020

AbstractCu(In,Ga)Se2‐based (CIGS) solar cells with ultrathin (≤500 nm) absorber layers suffer from the low reflectivity of conventional Mo back contacts. Here, we design and investigate ohmic and reflective back contacts (RBC) made of multilayer stacks that are compatible with the direct deposition of CIGS at 500°C and above. Diffusion mechanisms and reactions at each interface and in the CIGS layer are carefully analyzed by energy dispersive X‐ray (EDX)/scanning transmission electron microscopy (STEM). It shows that the highly reflective silver mirror is efficiently encapsulated in ZnO:Al layers. The detrimental reaction between CIGS and the top In2O3:Sn (ITO) layer used for ohmic contact can be mitigated by adding a 3 nm thick Al2O3 layer and by decreasing the CIGS coevaporation temperature from 550°C to 500°C. It also improves the compositional grading of Ga toward the CIGS back interface, leading to increased open‐ circuit voltage and fill factor. The best ultrathin CIGS solar cell on RBC exhibits an efficiency of 13.5% (+1.0% as compared to our Mo reference) with a short‐circuit current density of 28.9 mA/cm2 (+2.6 mA/cm2) enabled by double‐pass absorption in the 510 nm thick CIGS absorber. RBC are easy to fabricate and could benefit other photovoltaic devices that require highly reflective and conductive contacts subject to high temperature processes.
Trends in the Physical Medicine and Rehabilitation Match: Analysis of NRMP Data from 2007 to 2018
Authors: Claus Deanna , Anderson Dustin , Staley Vera , Forster Jeri , Meron Adele 
Published: November 2020

AbstractIntroductionWe provide an updated analysis of data about U.S. Physical Medicine and Rehabilitation (PM&R) residency program applicants collected by the National Resident Matching Program (NRMP).ObjectiveAnalyze trends within NRMP data for PM&R residency match rates, compare matched to unmatched applicants, and compare PM&R applicants to other medical specialties.DesignSecondary analysis of NRMP data.SettingNRMP data set.ParticipantsResidency program applicants who participated in the NRMP Match, 2007 to 2018.InterventionsNot applicable.Main Outcome MeasuresNumber of applicants, match rates, difference in characteristics including rank order list (ROL), U.S. Medical Licensing Examination (USMLE) Step 1 and Step 2 Clinical Knowledge (CK) scores, publications, Alpha Omega Alpha (AOA) status, PhD degree, and experiences in research, volunteer, and work.ResultsNumber of applicants and residency positions increased from 2007 to 2018. Length of ROL increased and was longer for matched compared to unmatched applicants, with maximum mean difference of 7.4 in 2016 (95% confidence interval [CI] 5.6‐9.2). Matched U.S. Allopathic Seniors had higher USMLE scores compared to unmatched, with a mean difference of 12.7 for Step 1 (95% CI 8.3‐17.0) and 12.6 (95% CI 8.6‐16.6) for Step 2 CK (P < .001). Number of publications and volunteer experiences were higher for matched U.S. Allopathic Seniors (0.64, 95% CI 0.09‐1.2 and 1.5, 95% CI 0.65‐2.3, respectively). PM&R USMLE Step 1 and 2 CK scores increased at a significantly faster rate than for all other specialties, with estimated rate differences of 0.46 (95% CI 0.21‐0.71) and 0.69 (95% CI 0.45‐0.93) points per year, respectively.ConclusionsPM&R residency has become more competitive. USMLE Step 1 and 2 CK scores have outpaced the inflation of scores in other specialties. ROL length has increased, suggesting more ranked programs to successfully match. These analyses update our knowledge about PM&R residency applicants and suggest surrogate markers for a successful match.
Solution structures of the Shewanella woodyiH‐NOX protein in the presence and absence of soluble guanylyl cyclase stimulator IWP‐051
Authors: Chen Cheng‐Yu , Lee Woonghee , Renhowe Paul A. , Jung Joon , Montfort William R. 
Published: November 2020

AbstractHeme‐nitric oxide/oxygen binding (H‐NOX) domains bind gaseous ligands for signal transduction in organisms spanning prokaryotic and eukaryotic kingdoms. In the bioluminescent marine bacterium Shewanella woodyi (Sw), H‐NOX proteins regulate quorum sensing and biofilm formation. In higher animals, soluble guanylyl cyclase (sGC) binds nitric oxide with an H‐NOX domain to induce cyclase activity and regulate vascular tone, wound healing and memory formation. sGC also binds stimulator compounds targeting cardiovascular disease. The molecular details of stimulator binding to sGC remain obscure but involve a binding pocket near an interface between H‐NOX and coiled‐coil domains. Here, we report the full NMR structure for CO‐ligated Sw H‐NOX in the presence and absence of stimulator compound IWP‐051, and its backbone dynamics. Nonplanar heme geometry was retained using a semi‐empirical quantum potential energy approach. Although IWP‐051 binding is weak, a single binding conformation was found at the interface of the two H‐NOX subdomains, near but not overlapping with sites identified in sGC. Binding leads to rotation of the subdomains and closure of the binding pocket. Backbone dynamics are similar across both domains except for two helix‐connecting loops, which display increased dynamics that are further enhanced by compound binding. Structure‐based sequence analyses indicate high sequence diversity in the binding pocket, but the pocket itself appears conserved among H‐NOX proteins. The largest dynamical loop lies at the interface between Sw H‐NOX and its binding partner as well as in the interface with the coiled coil in sGC, suggesting a critical role for the loop in signal transduction.
Fragments recombination, design, synthesis, safener activity and CoMFA model of novel substituted dichloroacetylphenyl sulfonamide derivatives
Authors: Wang Zi‐Wei , Zhao Li‐Xia , Ma Peng , Ye Tong , Fu Ying , Ye Fei 
Published: November 2020

AbstractBACKGROUNDIsoxaflutole (IXF), as a kind of 4‐hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor, has been widely used in many kinds of plants. IXF can cause injury in corn including leaf and stem bleaching, plant height reduction or stunting, and reduced crop stand. Safeners are co‐applied with herbicides to protect crops without compromising weed control efficacy. With the ultimate goal of addressing Zea mays injury caused by IXF, a series of novel substituted dichloroacetylphenyl sulfonamide derivatives was designed on the basis of scaffold hopping and active substructure splicing.RESULTSA total of 35 compounds were synthesized via acylation reactions. All the compounds were characterized by infrared (IR), proton and carbon‐13 nuclear magnetic resonance (1H‐NMR and 13C‐NMR), and high‐resolution mass spectrometry (HRMS). The configuration of compound II‐1 was confirmed by single crystal X‐ray diffraction. The bioassay results showed that all the title compounds displayed remarkable protection against IXF via improved content of carotenoid. Especially compound II‐1 which possessed better glutathione transferases (GSTs) activity and carotenoid content than the contrast safener cyprosulfamide (CSA). All the satisfied parameters suggested that the Comparative Molecular Field Analysis (CoMFA) model was reliable and stable [with a cross‐validated coefficient (q2) = 0.527, r2 = 0.995, r2 pred = 0.931]. The molecular docking simulation indicated that the compound II‐1 and CSA could compete with diketonitrile (DKN) at the active site of HPPD, which is a hydrolyzed product of IXF in plants, causing the herbicide to be ineffective.CONCLUSIONSThe present work revealed that the compound II‐1 deserves further attention as the candidate structure of safeners. © 2020 Society of Chemical Industry
Investigating the presence of compensatory evolution in dicamba resistant IAA16 mutated kochia (Bassia scoparia)†
Authors: Wu Chenxi , Paciorek Marta , Liu Kang , LeClere Sherry , Perez‐Jones Alejandro , Westra Phil , Sammons R Douglas 
Published: November 2020

AbstractBACKGROUNDLack of fitness costs has been reported for multiple herbicide resistance traits, but the underlying evolutionary mechanisms are not well understood. Compensatory evolution that ameliorates resistance costs, has been documented in bacteria and insects but rarely studied in weeds. Dicamba resistant IAA16 (G73N) mutated kochia was previously found to have high fecundity in the absence of competition, regardless of significant vegetative growth defects. To understand if costs of dicamba resistance can be compensated through traits promoting reproductive success in kochia, we thoroughly characterized the reproductive growth and development of different G73N kochia biotypes. Flowering phenology, seed production and reproductive allocation were quantified through greenhouse studies, floral (stigma‐anthers distance) and seed morphology, as well as resulting mating and seed dispersal systems were studied through time‐course microcopy images.RESULTSG73N covaried with multiple phenological, morphological and ecological traits that improve reproductive fitness: (i) 16–60% higher reproductive allocation; (ii) longer reproduction phase through early flowering (2–7 days); (iii) smaller stigma‐anthers separation (up to 60% reduction of herkogamy and dichogamy) that can potentially promote selfing and reproductive assurance; (iv) ‘winged’ seeds with 30–70% longer sepals that facilitate long‐distance seed dispersal.CONCLUSIONThe current study demonstrates that costs of herbicide resistance can be ameliorated through coevolution of other fitness penalty alleviating traits. As illustrated in a hypothetical model, the evolution of herbicide resistance is an ongoing fitness maximization process, which poses challenges to contain the spread of resistance. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Absolute quantitation of propranolol from 200‐μm regions of mouse brain and liver thin tissues using laser ablation‐dropletProbe‐mass spectrometry
Authors: Kertesz Vilmos , Cahill John F. , Srijanto Bernadeta R. , Collier Charles P. , Vavrek Marissa , Chen Bingming 
Published: November 2020

RationaleThe ability to quantify drugs and metabolites in tissue with sub‐mm resolution is a challenging but much needed capability in pharmaceutical research. To fill this void, a novel surface sampling approach combining laser ablation with the commercial dropletProbe automated liquid surface sampling system (LA‐dropletProbe) was developed and is presented here.MethodsParylene C‐coated 200 × 200 μm tissue regions of mouse brain and kidney thin tissue sections were analyzed for propranolol by laser ablation of tissue directly into a preformed liquid junction. Propranolol was detected by high‐performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) in positive electrospray ionization mode. Quantitation was achieved via application of a stable‐isotope‐labeled internal standard and an external calibration curve.ResultsThe absolute concentrations of propranolol determined from 200 × 200 μm tissue regions were compared with the propranolol concentrations obtained from 2.3‐mm‐diameter tissue punches of adjacent, non‐coated sections using standard bulk tissue extraction protocols followed by regular HPLC/MS/MS analysis. The average concentration of propranolol in both organs determined by the two employed methods agreed to within ±12%. Furthermore, the relative abundances of phase II hydroxypropranolol glucuronide metabolites were recorded and found to be consistent with previous results.ConclusionsThis work illustrates that depositing a thin layer of parylene C onto thin tissue prior to analysis, which seals the surface and prevents direct liquid extraction of the drug from the tissue, coupled to the novel LA‐dropletProbe surface sampling system is a viable approach for sub‐mm resolution quantitative drug distribution analysis.
Organ‐on‐a‐Chip: A Preclinical Microfluidic Platform for the Progress of Nanomedicine
Authors: Rodrigues Raquel O. , Sousa Patrícia C. , Gaspar João , Bañobre‐López Manuel , Lima Rui , Minas Graça 
Published: November 2020

AbstractDespite the progress achieved in nanomedicine during the last decade, the translation of new nanotechnology‐based therapeutic systems into clinical applications has been slow, especially due to the lack of robust preclinical tissue culture platforms able to mimic the in vivo conditions found in the human body and to predict the performance and biotoxicity of the developed nanomaterials. Organ‐on‐a‐chip (OoC) platforms are novel microfluidic tools that mimic complex human organ functions at the microscale level. These integrated microfluidic networks, with 3D tissue engineered models, have been shown high potential to reduce the discrepancies between the results derived from preclinical and clinical trials. However, there are many challenges that still need to be addressed, such as the integration of biosensor modules for long‐time monitoring of different physicochemical and biochemical parameters. In this review, recent advances on OoC platforms, particularly on the preclinical validation of nanomaterials designed for cancer, as well as the current challenges and possible future directions for an end‐use perspective are discussed.
Electrodynamic Force, Casimir Effect, and Stiction Mitigation in Silicon Carbide Nanoelectromechanical Switches
Authors: Yang Rui , Qian Jiang , Feng Philip X.‐L. 
Published: November 2020

AbstractLogic switches enabled by nanoelectromechanical systems (NEMS) offer abrupt on/off‐state transition with zero off‐state leakage and minimal subthreshold swing, making them uniquely suited for enhancing mainstream electronics in a range of applications, such as power gating, high‐temperature and high‐voltage logic, and ultralow‐power circuits requiring zero standby leakage. As NEMS switches are scaled with genuinely nanoscale gaps and contacts, quantum mechanical electrodynamic force (EDF) takes an important role and may be the ultimate cause of the plaguing problem of stiction. Here, combined with experiments on three‐terminal silicon carbide (SiC) NEMS switches, a theoretical investigation is performed to elucidate the origin of EDF and Casimir effect leading to stiction, and to develop a stiction‐mitigation design. The EDF calculation with full Lifshitz formula using the actual material and device parameters is provided. Finite element modeling and analytical calculations demonstrate that EDF becomes dominant over elastic restoring force in such SiC NEMS when the switching gap shrinks to a few nanometers, leading to irreversible stiction at contact. Artificially corrugated contact surfaces are designed to reduce the contact area and the EDF, thus evading stiction. This rational surface engineering reduces the EDF down to 4% compared with the case of unengineered, flat contact surfaces.
Reproductive organ dysfunction and gene expression after orally administration of ZnO nanoparticles in murine
Authors: Kuang Huijuan , Zhang Wanyi , Yang Lin , Aguilar Zoraida P. , Xu Hengyi 
Published: November 2020

AbstractZnO nanoparticles (NPs) are among the most manufactured nanoparticles in the consumer products, industries, and researches. An increasing body of evidence indicated that ZnO NPs show toxicological effects in vivo. Sex differences in the toxicity of ZnO NPs are not clear, thus the aim of this study was to investigate the effects of ZnO NPs on the female and male reproductive organs (uterus, ovary and testes). ZnO NPs were orally administered to female and male mice at dosages level of 0 and 100 mg/kg body weight. The biological material was sampled 3 days after tube feeding. The results demonstrated that Zinc contents were accumulated in the reproductive organs of treated mice. Furthermore, ZnO NPs administration induced significant decrease in the testes weight, an imbalance of hematological and serum biochemical parameters in male mice. The histopathological examinations showed that structural disorder and the appearance of cell apoptosis and death in the ZnO NPs‐exposed mice. Additionally, the RT‐qPCR data indicated ZnO NPs can activate mitochondrial‐mediated signaling pathway and induce caspase depend damage that ultimately injured the uterus. In the ovary, ZnO NPs induce cell apoptosis in Shh pathway activated ovary cells, and affect the synthesis of steroidogenesis. In the testes, ZnO NPs effectively changed the expression level of genes related to oxidant stress, detox/metabolic process, and apoptosis. It was found that ZnO NPs caused more serious reproductive toxicity in the male mice than female mice. Overall, these findings indicated that ZnO NPs could induce exposure‐related risks to reproductive health, especially in those who are at the occupational level.
Removing crotamiton from reverse osmosis concentrate by using coagulation and a rotating advanced oxidation contactor
Authors: Xiang Qun , Fukahori Shuji , Yamashita Naoyuki , Tanaka Hiroaki , Fujiwara Taku 
Published: November 2020

AbstractA novel rotating advanced oxidation contactor (RAOC) equipped with a composite titanium dioxide–zeolite sheet was used to remove the antipruritic agent crotamiton from reverse osmosis concentrate with coagulation as a pretreatment. Coagulation was more efficient at pH 5 in terms of reducing total organic carbon and light absorbance, and the efficiency of coagulation improved with an increase in polymeric aluminum dosage from 0 to 6 mmol/L Al3+. The RAOC performed well in adsorbing crotamiton without obvious inhibition by other components in the reverse osmosis concentrate, and a majority of the crotamiton was removed after 6 h, resulting in the purification of the treated solution. With ultraviolet irradiation, crotamiton was simultaneously removed through adsorption and photocatalysis by the RAOC. The behavior of the main degradation intermediates of crotamiton during treatment showed that the degradation intermediates were also captured by the composite sheet. Coagulation followed by treatment with the RAOC was effective in the removal of organic matter in the RO concentrate and in the photocatalytic degradation of crotamiton.
Saccharomyces spores are born prepolarized to outgrow away from spore–spore connections and penetrate the ascus wall
Authors: Heasley Lydia R. , Singer Emily , Cooperman Benjamin J. , McMurray Michael A. 
Published: November 2020

AbstractHow nonspore haploid Saccharomyces cells choose sites of budding and polarize towards pheromone signals in order to mate has been a subject of intense study. Unlike nonspore haploids, sibling spores produced via meiosis and sporulation by a diploid cell are physically interconnected and encased in a sac derived from the old cell wall of the diploid, called the ascus. Nonspore haploids bud adjacent to previous sites of budding, relying on stable cortical landmarks laid down during prior divisions, but because spore membranes are made de novo, it was assumed that, as is known for fission yeast, Saccharomyces spores break symmetry and polarize at random locations. Here, we show that this assumption is incorrect: Saccharomyces cerevisiae spores are born prepolarized to outgrow, prior to budding or mating, away from interspore bridges. Consequently, when spores bud within an intact ascus, their buds locally penetrate the ascus wall, and when they mate, the resulting zygotes adopt a unique morphology reflective of repolarization towards pheromone. Long‐lived cortical foci containing the septin Cdc10 mark polarity sites, but the canonical bud site selection programme is dispensable for spore polarity, thus the origin and molecular composition of these landmarks remain unknown. These findings demand further investigation of previously overlooked mechanisms of polarity establishment and local cell wall digestion and highlight how a key step in the Saccharomyces life cycle has been historically neglected.