bluuebunny/crossref_metadata_2025 huggingface dataset:
Defining the anatomy of the neonatal lingual frenulum
Authors: Mills Nikki , Keough Natalie , Geddes Donna T. , Pransky Seth M. , Mirjalili S. Ali
Published: May 2019

The lingual frenulum is recognized as having the potential to limit tongue mobility, which may lead to difficulties with breastfeeding in some infants. There is extensive variation between individuals in the appearance of the lingual frenulum but an ambiguous relationship between frenulum appearance and functional limitation. An increasing number of infants are being diagnosed with ankyloglossia, with growing uncertainty regarding what can be considered “normal” lingual frenulum anatomy. In this study, microdissection of four fresh tissue premature infant cadavers shows that the lingual frenulum is a dynamic, layered structure formed by oral mucosa and the underlying floor of mouth fascia, which is mobilized into a midline fold with tongue elevation and/or retraction. Genioglossus is suspended from the floor of mouth fascia, and in some individuals can be drawn up into the fold of the frenulum. Branches of the lingual nerve are located superficially on the ventral surface of the tongue, immediately beneath the fascia, making them vulnerable to injury during frenotomy procedures. This research challenges the longstanding belief that the lingual frenulum is a midline structure formed by a submucosal “band” or “string” and confirms that the neonatal lingual frenulum structure replicates that recently described in the adult. This article provides an anatomical construct for understanding and describing variability in lingual frenulum morphology and lays the foundation for future research to assess the impact of specific anatomic variants of lingual frenulum morphology on tongue mobility. Clin. Anat. 32:824–835, 2019. © 2019 The Authors. Clinical Anatomy published by Wiley Periodicals, Inc. on behalf of American Association of Clinical Anatomists.
Robust simultaneous localization and mapping in low‐light environment
Authors: Huang Jiawei , Liu Shiguang
Published: May 2019

Complex and varied illumination makes computer vision research studies difficult. This research field pays much attention to scenes with weak illumination, especially in visual simultaneous localization and mapping (SLAM). Although the current feature‐based algorithm is mature, the existing SLAM method often fails because it cannot extract enough feature information in the low‐light environment. In this paper, we propose a new solution to this problem, which allows our system to work in environments with the majority of lighting. We propose a multifeature extraction algorithm to extract two kinds of image features simultaneously. With such a solution, our system can work when the single‐feature algorithm fails to extract enough feature points. We also add an image preprocessing step before tracking thread to cope with extremely dark conditions. Finally, we fully evaluate our approach on existing public data sets. Experiments show that the method combining multiple features can improve the robustness of the state‐of‐the‐art algorithm under weak illumination without affecting the real‐time performance.
Polarization Effects of a Rayon and Polyacrylonitrile Based Graphite Felt for Iron‐Chromium Redox Flow Batteries
Authors: Zhang Huan , Tan Yi , Luo Xu‐Dong , Sun Chuan‐Yu , Chen Na
Published: May 2019

In this paper, a rayon based graphite felt (R‐GF) and a polyacrylonitrile based graphite felt (PAN‐GF) are studied to clarify the influence of the precursor on the polarization effect from three aspects: concentration polarization, ohmic polarization, and electrochemical polarization. The essential difference in chemical structure between R‐GF and PAN‐GF is that the precursor material makes PAN‐GF easier to be graphitized. The higher degree of graphitization leads to a higher conductivity of PAN‐GF. At the same thickness and porosity, the conductivity of PAN‐GF is higher and the loss of ohmic polarization is smaller. These factors make PAN‐GF have better electrocatalytic properties and kinetic reversibility in the Fe/Cr electrolyte environment. While the surface roughness of R‐GF is larger, which is contributing to the diffusion and surface mass transfer of the electrolyte on the surface. The effect of precursor on the concentration polarization of R‐GF and PAN‐GF is related to the surface mass transfer, which ultimately affects the performance of ICRFB.
Electrochemical CO2 Reduction on Bimetallic Surface Alloys: Enhanced Selectivity to CO for Co/Au(110) and to H2 for Sn/Au(110)
Authors: Todoroki Naoto , Tei Hiroki , Miyakawa Taku , Tsurumaki Hiroto , Wadayama Toshimasa
Published: May 2019

We investigated electrochemical CO2 reduction (ECR) on 0.1 monolayer‐thick‐Co and Sn‐deposited Au(110) surfaces (Co/Au(110), and Sn/Au(110)). Scanning tunneling microscopic images showed quasi‐one‐dimensional Co and Sn islands with different aspect ratios growing along the trenches of the missing‐row direction of the (1×2) reconstructed Au(110) surface. The selectivity and partial current density of the CO and H2 evolutions correlated with those of the deposited metals. CO evolution selectivity of the former Co/Au(110) increased compared with that of the Au(110), while that of the Sn/Au(110) significantly decreased. Co/Au(110) showed 1.4‐fold higher CO evolution activity than that of the clean Au(110) at −1.35 V vs. reversible hydrogen electrode. In contrast, the H2 evolution of the latter surface was significantly enhanced at a potential lower than −0.1 V. The results showed that site separations of Au and alloying elements of Co and Sn at the topmost surface determine the ECR product selectivity of alloy electrodes.
Dismutation of Titanium Sub‐oxide into TiO and TiO2 with Structural Hierarchy Assisted by Ammonium Halides
Authors: Huang Jiantao , Xu Jijian , Che Xiangli , Huang Chong
Published: May 2019

Black TiO2−x attracts enormous attention due to its large solar absorption and improved conductivity. In this work, a novel structure of TiO2−x with conductive TiO layer, performing full‐spectrum absorption, was synthesized in one step by the unforeseen dismutation reaction of titanium sub‐oxides (TinO2n−1) in ammonium halide atmosphere. For this new reaction, a possible mechanism of decomposition‐etching‐disproportionation‐rehydrolysis process was proposed. The vital intermediate reactant TiCl4, which verifies the assumption, has been captured in the form of (NH4)2TiCl6, especially where Ti2O3 is the reactant. Furthermore, this work not only can nominate TiO as an alternative for noble metals or carbon materials in the aim to improve the electron conductivity and solar absorption of black TiO2−x, which are important in electrochemistry and optoelectronics fields, but also can be a new route to synthesize special structures for other multivalent transition metals.
Immunohistochemical validation studies in effusion cytology: A cautionary tale
Authors: Pillappa Raghavendra , Kraft Adele O.
Published: May 2019

Besides the established uses in tumor diagnosis and characterization, immunohistochemical assays of effusion fluids are being increasingly used as substrates for prognostic and predictive markers. This commentary highlights validation issues encountered in daily practice that may have an impact on assay interpretation.
A Phthalocyanine‐Based Glutathione‐Activated Photosensitizer with a Ferrocenyl Boron Dipyrromethene Dark Quencher for Photodynamic Therapy
Authors: Shi Wen‐Jing , Ng Dennis K. P. , Zhao Shirui , Lo Pui‐Chi
Published: May 2019

An efficient near‐infrared‐absorbing dark quencher based on ferrocenyl boron dipyrromethene (BODIPY) has been developed and used to construct a fluorescence resonance energy transfer (FRET)‐based activatable photosensitizer. This smart photosensitizer contains a zinc(II) phthalocyanine as the photosensitizing unit which is conjugated to this dark quencher through a glutathione‐cleavable disulfide linker. The photoactivities of the phthalocyanine unit are largely quenched through FRET to the BODIPY unit followed by photoinduced electron transfer from the attached ferrocenyl moiety. Upon exposure to glutathione in phosphate buffered saline and inside HT29 human colorectal adenocarcinoma cells, the fluorescence emission and singlet oxygen generation efficiency of the photosensitizer are significantly enhanced due to cleavage of the disulfide bond and detachment of the dark quencher from the photosensitizing unit. The activation in fluorescence emission has also been demonstrated in tumor‐bearing nude mice. The glutathione‐responsive behavior has been verified by comparison with the negative results of a non‐cleavable analogue. The results suggest that ferrocenyl BODIPYs could serve as tailorable dark quenchers and the disulfide‐linked phthalocyanine–quencher conjugate acts as an efficient glutathione‐activated photosensitizer for photodynamic therapy.
Dinuclear Copper(I) Complexes Combining Bis(diphenylphosphaníyl)acetylene with 1,10‐Phenanthroline Ligands
Authors: Nierengarten Jean‐François , Nierengarten Iwona , Holler Michel , Sournia‐Saquet Alix , Delavaux‐Nicot Béatrice , Leoni Enrico , Monti Filippo , Armaroli Nicola
Published: May 2019

Invited for the cover of this issue are Jean‐François Nierengarten (University of Strasbourg and CNRS, France), Béatrice Delavaux‐Nicot (LCC, CNRS, Toulouse, France), and Nicola Armaroli (ISOF, CNR, Bologna, Italy). The cover image shows the X‐ray crystal structure of a luminescent dinuclear copper(I) complex with an artistic representation of its emission in the background.
A Ring Expansion Route to Benzofused N‐Heterocycles Through Aryne Insertion into 1,3‐Diaza‐heterocycles
Authors: Yang Yun , Xu Yue , Jones Christopher R.
Published: May 2019

Arynes have been found to undergo formal σ‐bond insertion into a C(sp3)–N bond for the first time. This transformation is utilized in the ring expansion of 1,3‐diaza‐heterocycles to afford benzofused medium‐ring N‐heterocycles in a single step. This represents a novel route to biologically relevant 2,3,4,5‐tetrahydro‐1H‐benzo[e][1,4]diazepines, prepared directly from easily accessible imidazolidines. An example of the ring expansion of a 1,3‐diazetidine is also reported, which affords the corresponding 1,2,3,4‐tetrahydroquinazoline.
The relation of self‐compassion to functioning among adults with chronic pain
Authors: Edwards Karlyn A. , Pielech Melissa , Hickman Jayne , Ashworth Julie , Sowden Gail , Vowles Kevin E.
Published: May 2019

Background

Previous research has shown that self‐compassion is associated with improved functioning and health outcomes among multiple chronic illnesses. However, the role of self‐compassion in chronic pain‐related functioning is understudied. The present study sought to understand the association between self‐compassion and important measures of functioning within a sample of patients with chronic pain.

Methods

Treatment‐seeking individuals (N = 343 with chronic pain) that were mostly White (97.9%) and female (71%) completed a battery of assessments that included the Self‐Compassion Scale (SCS), as well as measures of pain‐related fear, depression, disability, pain acceptance, success in valued activity and use of pain coping strategies.

Results

Cross‐sectional multiple regression analyses that controlled for age, sex, pain intensity and pain duration, revealed that self‐compassion accounted for a significant and unique amount of variance in all measures of functioning (r2 range: 0.07–0.32, all p < 0.001). Beta weights indicated that higher self‐compassion was associated with lower pain‐related fear, depression and disability, as well as greater pain acceptance, success in valued activities and utilization of pain coping strategies.

Conclusions

These findings suggest that self‐compassion may be a relevant adaptive process in those with chronic pain. Targeted interventions to improve self‐compassion in those with chronic pain may be useful.

Significance

Self‐compassion is associated with better functioning across multiple general and pain‐specific outcomes, with the strongest associations among measures related to psychological functioning and valued living. These findings indicate that self‐compassion may be an adaptive process that could minimize the negative impact of chronic pain on important areas of life.
Poly(Taurine‐Glutathione)/Carbon Nanotube Modified Glassy Carbon Electrode as a New Levofloxacin Sensor
Authors: Koçak Çağrı Ceylan
Published: May 2019

A new highly sensitive and selective electrochemical levofloxacin sensor based on co‐polymer‐carbon nanotube composite electrode was developed. Taurine and Glutathione were electrochemically co‐polymerized on multiwalled carbon nanotubes modified glassy carbon electrode(Poly(TAU‐GSH)/CNT/GCE)and used as a levofloxacin sensor in pH 6 phosphate buffer solution. The new composite electrode surfaces were characterized by scanning electron microscopy, atomic force microscopy and electrochemical impedance spectroscopy. Under the optimized conditions, two linear segments were obtained for increasing LEV concentrations between 20 nmol L−1‐1 μmol L−1and 1.5 μmol L−1‐55 μmol L−1LEV with a detection limit of 9 nmol L−1using amperometry.Poly(TAU‐GSH)/CNT/GCEexhibited high sensitivity, selectivity with good stability. The new sensor was employed for real samples of LEV tablets and urine. Promising results were obtained with good accuracy which were also in accordance with LC‐MS/MS analysis.
A Combinatorial Approach for Optimization of Oxygen Evolution Catalyst Loading on Mo‐doped BiVO4 Photoanodes
Authors: Gutkowski Ramona , Masa Justus , Schuhmann Wolfgang
Published: May 2019

The incident photon to current efficiency (IPCE) of a photoactive surface strongly depends on the loading and thickness of the active materials. We present a combinatorial approach based on an optical scanning droplet cell for simultaneous deposition and systematic characterization of co‐catalysts for the oxygen evolution reaction (OER) on Mo‐doped BiVO4 (Mo−BiVO4) photoanodes electrochemically pre‐deposited on transparent conductive FTO substrates. The loading and photoelectrochemical characterization of 10 different OER co‐catalysts deposited by three different deposition techniques on FTO‐supported Mo−BiVO4 were investigated aiming at determination of the suitable deposition parameters affording the highest enhancement of photoelectrochemical oxygen evolution for the different OER/Mo−BiVO4 films. A comparison of the photoelectrochemical performance of films of various OER co‐catalyst deposited on FTO‐supported Mo−BiVO4 by electrodeposition, photo‐assisted electrodeposition and photodeposition revealed the necessity of a material specific optimization with respect to co‐catalyst loading and deposition technique to achieve optimal IPCE for each co‐catalysts.
Microfluidic Device Using a Gold Pillar Array and Integrated Electrodes for On‐chip Endothelial Cell Immobilization, Direct RBC Contact, and Amperometric Detection of Nitric Oxide
Authors: Townsend Alexandra D. , Sprague Randy S. , Martin R. Scott
Published: May 2019

We describe a microfluidic device that can be used to detect interactions between red blood cells (RBCs) and endothelial cells using a gold pillar array (created by electrodeposition) and an integrated detection electrode. Endothelial cells can release nitric oxide (NO) via stimulation by RBC‐derived ATP. These studies incorporate on‐chip endothelial cell immobilization, direct RBC contact, and detection of NO in a single microfluidic device. In order to study the RBC‐EC interactions, this work used a microfluidic device made of a PDMS chip with two adjacent channels and a polystyrene base with embedded electrodes for creating a membrane (via gold pillars) and detecting NO (at a glassy carbon electrode coated with platinum‐black and Nafion). RBCs were pharmacologically treated with treprostinil in the absence and presence of glybenclamide, and ATP release was determined as was the resultant NO release from endothelial cells. Treprostinil treatment of RBCs resulted in ATP release that stimulated endothelial cells to release on average 1.8±0.2 nM NO per endothelial cell (average±SEM, n=8). Pretreatment of RBCs with glybenclamide inhibited treprostinil‐induced ATP release and, therefore, less NO was produced by the endothelial cells (0.92±0.1 nM NO per endothelial cell, n=7). In the future, this device can be used to study interactions between many other cell types (both adherent and non‐adherent cell lines) and incorporate other detection schemes.
Graphene quantum dots for enhancement of fluorimetric detection coupled to capillary electrophoresis for detection of ofloxacin
Authors: Lahouidak Samah , Soriano M. Laura , Salghi Rachid , Zougagh Mohammed , Ríos Ángel
Published: May 2019

A new CE method with fluorescence detection is reported on the determination of ofloxacin in milk samples using graphene quantum dots (GQDs) for sensitivity enhancement. Injection of GQDs prior the standards/sample is crucial to increase the antibiotic fluorescence response. Clean‐up and preconcentration steps allowed for a good linear correlation in a concentration range between 50 and 1000 ng/mL for the ofloxacin, detection and quantification limits being 10.7 and 35.5 ng/mL, respectively. Optimal CE conditions for the seven‐fluoroquinolone separation method were assessed in terms of buffer type, pH, and voltage. The selective interaction of GQDs with ofloxacin as model analyte was subsequently studied finding a significant sensitivity improvement; therefore, the analytes would be detected at low concentrations by means of a commercial CE device equipped with a multi‐wavelength photoluminescence detector. Due to the different maximum emission wavelengths of the target compounds and the limitations shown by the single‐wavelength photoluminescence detector coupled to the CE system, we demonstrated the usefulness of the GQD‐assisted sensitivity‐enhanced CE method to determine ofloxacin in milk samples. This work opens an interesting possibility of using GQDs in separation techniques combined with photoluminescence detectors for lowering sensitivity levels typically provided by the mere device.
Spatial cluster detection of regression coefficients in a mixed‐effects model
Authors: Lee Junho , Sun Ying , Chang Howard H.
Published: May 2019

Identifying spatial clusters of different regression coefficients is a useful tool for discerning the distinctive relationship between a response and covariates in space. Most of the existing cluster detection methods aim to identify the spatial similarity in responses, and the standard cluster detection algorithm assumes independent spatial units. However, the response variables are spatially correlated in many environmental applications. We propose a mixed‐effects model for spatial cluster detection that takes spatial correlation into account. Compared to a fixed‐effects model, the introduced random effects explain extra variability among the spatial responses beyond the cluster effect, thus reducing the false positive rate. The developed method exploits a sequential searching scheme and is able to identify multiple potentially overlapping clusters. We use simulation studies to evaluate the performance of our proposed method in terms of the true and false positive rates of a known cluster and the identification of multiple known clusters. We apply our proposed methodology to particulate matter (PM2.5) concentration data from the Northeastern United States in order to study the weather effect on PM2.5 and to investigate the association between the simulations from a numerical model and the satellite‐derived aerosol optical depth data. We find geographical hot spots that show distinct features, comparing to the background.
Seed ontogeny in Eupatorieae: development and functional aspects
Authors: Marzinek Juliana , Oliveira Denise Maria Trombert
Published: May 2019

Changes in the role of the seed coat during seed development have not been extensively examined, mainly because the greater emphasis is usually placed upon its function in the mature seed. Additionally, there have been few studies on the seeds of Asteraceae, and those that have been undertaken rarely addressed functional aspects of seeds. The present study examined seed ontogeny in species of Eupatorieae (Asteraceae) and investigated the role of the seed coat in seed nutrition and abortion. A new pattern of seed vasculature was encountered for the family, in addition to two other types previously described for other species. The most significant role of the seed coat among the species of Eupatorieae examined was in seed nutrition. The inner mesotesta is consumed during seed development, while the remaining layers collapse at maturity and cease to function. Seed abortion was observed in all of the species examined, varying from 95% in Symphyopappus reticulatus to 18.5% in Vittetia orbiculata. Changes in endothelial tissue were found in all episodes of abortion, although variation was observed concerning remnant structures and their degree of development. The young seed coat in Asteraceae has a nutritive role, while at maturation the pericarp serves a protective function.
Young people who inject drugs in India have high HIV incidence and behavioural risk: a cross‐sectional study
Authors: Ganapathi Lakshmi , McFall Allison M , Srikrishnan Aylur K , Kumar Muniratnam S , Anand Santhanam , Lucas Gregory M , Mehta Shruti H , Harris Sion K , Solomon Sunil S
Published: May 2019

Introduction

There are limited data on young people who inject drugs (PWID) from low‐ and middle‐income countries where injection drug use remains a key driver of new HIV infections. India has a diverse injection drug use epidemic and estimates suggest that at least half of PWID are ≤30 years of age. We compared injection and sexual risk behaviours and HIV incidence between younger and older PWID and characterized uptake of HIV testing and harm reduction services to inform targeted HIV prevention efforts.

Methods

We analysed cross‐sectional data from 14,381 PWID recruited from cities in the Northeast and North/Central regions of India in 2013 using respondent driven sampling (RDS). We compared “emerging‐adult” (18 to 24 years, 26% of sample) and “young‐adult” PWID (25 to 30 years, 30% of sample) to older PWID (>30 years, 44% of sample) using logistic regression to evaluate factors associated with three recent risk behaviours: needle‐sharing, multiple sexual partners and unprotected sex. We estimated age‐stratified cross‐sectional HIV incidence using a validated multi‐assay algorithm.

Results

Compared to older adults, emerging‐adults in the Northeastern states were significantly more likely to share needles (males adjusted odds ratio [aOR] 1.82; females aOR 2.29, p < 0.01), have multiple sexual partners (males aOR 1.56; females aOR 3.75, p < 0.01), and engage in unprotected sex (males aOR 2.29, p < 0.01). In the North/Central states, young‐adult males were significantly more likely to needle‐share (aOR 1.23, p < 0.05) while emerging‐adult males were significantly more likely to have multiple sexual partners (aOR 1.74, p < 0.05). In both regions, emerging‐adults had the lowest HIV testing. Participation in harm reduction services was low across all age groups. Annual HIV incidence was higher in emerging‐ and young‐adult PWID in the North/Central region: emerging‐adults: 4.3% (95% confidence interval [CI] 3.0, 5.6); young‐adults: 4.9% (95% CI 3.7, 6.2); older adults: 2.1% (95% CI 1.4, 2.8).

Conclusions

Higher HIV incidence and engagement in risky behaviours among younger PWID compared to older PWID, coupled with low utilization of harm reduction services highlight the importance of targeting this population in HIV programming. Age‐specific interventions focused on addressing the needs of young PWID are urgently needed to curb the HIV epidemic in this vulnerable population.
The evaluation of time‐resolved Raman spectroscopy for the suppression of background fluorescence from space‐relevant samples
Authors: Hanke Franziska , Mooij Bram J.A. , Ariese Freek , Böttger Ute
Published: May 2019

One of the primary goals in space research is the search for signs of extant or extinct extraterrestrial life, and Raman spectroscopy can play a role in this field. Raman spectrometers are planned for future missions to Mars and possibly the Moon to identify the mineralogical surface composition and potentially existing organic compounds (especially on Mars). However, a major challenge in Raman spectroscopy, especially in the visible range, is the strong fluorescence background. Time‐resolved Raman spectroscopy (TRRS) can provide selective detection of Raman signals over the generally longer living fluorescence. This study investigates the potential of a TRRS system, using 3‐ps, 440‐nm laser pulses and time‐gated detection with an intensified charge‐coupled device (CCD) camera. Test samples were the lichen Xanthoria elegans as an extraterrestrial life analogue, and a lunar regolith analogue material (LRS) as a planetary surface analogue. The TRRS technique is evaluated by comparing gated to nongated Raman spectroscopy using different detectors but with otherwise the same instrument and identical measurement conditions. The gated spectra of X. elegans showed significant signal‐to‐noise ratio (SNR) improvements compared to the nongated spectra. The visible Raman lines could be assigned to the photoprotective pigment parietin. For the LRS sample, measurement spots with a good SNR in the nongated spectrum were not significantly improved by measuring in gated mode. However, spots dominated by fluorescence showed significant improvement in gated mode because of fluorescence suppression. Minerals such as plagioclase, diopside, olivine, apatite, and a carbonate mineral were detected. In most cases, TRRS provided better results compared to nongated measurements, demonstrating the suitability for future space‐exploration missions.
Controlled Growth of Polyamide Films atop Homogenous and Heterogeneous Hydrogels Using Gel–Liquid Interfacial Polymerization
Authors: Wang Mengyuan , Stafford Christopher M. , Cox Lewis M. , Blevins Adrienne K. , Aghajani Masoud , Killgore Jason P. , Ding Yifu
Published: May 2019

Controlled growth of crosslinked polyamide (PA) thin films is demonstrated at the interface of a monomer‐soaked hydrogel and an organic solution of the complementary monomer. Termed gel–liquid interfacial polymerization (GLIP), the resulting PA films are measured to be chemically and mechanically analogous to the active layer in thin film composite (TFC) membranes. PA thin films are prepared using the GLIP process on both a morphologically homogeneous hydrogel prepared from poly(2‐hydroxyethylmethacrylate) and a phase‐separated, heterogeneous hydrogel prepared from poly(acrylamide). Two monomer systems are examined: trimesoyl chloride (TMC) reacting with m‐phenylene diamine (MPD) and TMC reacting with piperazine (PIP). Unlike the self‐limiting growth behavior in TFC membrane fabrication, diffusion‐limited, continuous growth of the PA films is observed, where both the thickness and roughness of the PA layers increase with reaction time. A key morphological difference is found between the two monomer systems using the GLIP process; TMC/MPD produces a ridge‐and‐valley surface morphology whereas TMC/PIP produces nodule/granular structures. The GLIP process represents a unique opportunity to not only explore the pore characteristics (size, spacing, and continuity) on the resulting structure and morphology of the interfacially polymerized thin films, but also a method to modify the surface of (or encapsulate) hydrogels.
Evaluation of an automated grid artifact detection system for quality control in digital mammography
Authors: MacLellan Christopher J. , Layman Rick R. , Geiser William , Gress Dustin A. , Jones A. Kyle
Published: May 2019

Purpose

Grid artifacts occur in digital mammography when synchronization between the grid assembly and generator is not achieved, including when malfunctions occur in the grid assembly or generator subsystems. Such artifacts are not explicitly monitored or evaluated by existing mammography quality control programs. In this study, we developed an automated method for quantifying the presence of grid artifacts in two‐dimensional (2D) digital mammography images and assessed its utility as a supplement to existing quality control programs.

Methods

Four digital mammography systems (Hologic Dimensions 3D 5000) were configured to automatically transfer 2D images to a server where the strength of the grid pattern, γmax, was quantified using a template‐matching algorithm and stored in amySQL database. This analysis was performed on both American College of Radiology (ACR) phantom and clinical images. Changes in γmax were compared with image quality and service records to establish preliminary action limits for physicist intervention for each type of image. These action limits were applied around selected service events to evaluate their clinical utility.

Results

All systems exhibited a gradual increase in γmax in ACR phantom images prior to having identical major components of the generator subsystem replaced, despite the absence of visible gridlines in the images. Retrospective analysis of phantom images suggested that physicists should consider AEC testing when exceeds 0.050 and that clinical image quality may be affected when exceeds 0.060. Eighteen of 19 visible grid artifacts were identified using a threshold value of 0.065 in clinical images. Warning limits that indicate abnormal operation before visible degradation in image quality were also established. These warning limits were 0.046 and 0.041 for the 24 × 29 cm and 18 × 24 cm paddles, respectively. Specific malfunctions in the generator and grid subsystems can be detected by applying these limits.

Conclusions

Automated monitoring of provides useful information about the status of digital mammography units without affecting clinical operations. When used with appropriate action limits, this type of monitoring can help physicists identify specific equipment malfunctions before they would be detected by other quality control tests and before they affect clinical images.
Synthesis, Structural Characterization and Photodecarbonylation Study of a Dicarbonyl Ruthenium(II)‐Bisquinoline Complex
Authors: Kubeil Manja , Joshi Tanmaya , Wood Bayden R. , Stephan Holger
Published: May 2019

A photoactivatable ruthenium(II) carbonyl complex mer,cis‐[Ru(II)Cl(BisQ)(CO)2]PF6 2 was prepared using a tridentate bisquinoline ligand (BisQ=(2,6‐diquinolin‐2‐yl)pyridin). Compound 2 was thoroughly characterized by standard analytical methods and single crystal X‐ray diffraction. The crystal structure of the complex cation reveals a distorted octahedral geometry. The decarbonylation upon exposure to 350 and 420 nm light was monitored by UV/VIS absorbance and Fourier transform infrared spectroscopies in acetonitrile and 1 % (v/v) DMSO in water, respectively. The kinetic of the photodecarbonylation has been elucidated by multivariate curve resolution alternating least‐squares analysis. The stepwise decarbonylation follows a serial mechanism. The first decarbonylation occurs very quickly whereas the second decarbonylation step proceeds more slowly. Moreover, the second rate constant is lower in 1 % (v/v) DMSO in water than in acetonitrile. In comparison to 350 nm irradiation, exposure to 420 nm light in acetonitrile results in a lower second rate constant.
Teacher Incentives and Student Achievement: Evidence from an Advancement Program
Authors: Eren Ozkan
Published: May 2019

This paper examines the effects of a comprehensive performance pay program implemented in high‐need schools using administrative data from Louisiana. Exploiting the within‐student variation in the timing of implementation, we find a large and significant effect beginning with the second year of the program on math achievement. Similar but generally insignificant point estimates are observed in social studies. As for English Language Arts and science, there are no effects of the program. We provide evidence against changes in the composition of teacher workforce and postadoption student sorting as potential explanations for our results. We then show aggregate findings from a web‐survey that teachers may have altered their teaching practices following performance‐based compensation. Finally, under certain assumptions, we calculate the net present value of earnings impact to be close to a million dollars per school‐year for math.
The importance of cross‐disciplinary scientific engagement in the development of quantitative procedures for aggregate safety assessments
Authors: Ball Greg , Lievano Fabio
Published: May 2019

Recent guidance on safety monitoring during drug development, issued by regulatory authorities in the United States and European Union, indicate a shift in focus towards aggregate safety monitoring and scientific evaluation of integrated safety data. The call for program‐level reviews of accumulating safety data, including from ongoing studies, provides an opportunity to leverage the scientific expertise and medical judgment of safety management teams with (a) a multidisciplinary approach, (b) quantitative frameworks to measure level of evidence, and (c) assessments that are product‐specific and driven by medical judgment. A multidisciplinary team, regularly reviewing aggregate safety data throughout the development program, is vital not only for early signal detection but also for generating a better understanding of the accumulating data and context needed for decreasing false alarms.
Fostering sustainable improvements in science education: An analysis through four frames
Authors: Reinholz Daniel L. , Ngai Courtney , Quan Gina , Pilgrim Mary E. , Corbo Joel C. , Finkelstein Noah
Published: May 2019

There is a pressing need to improve the sustainability of educational improvement efforts, but sustainability remains undertheorized in science education. In this article, we draw upon frameworks from organizational culture and sustainability to characterize change within a single undergraduate science department. This in‐depth longitudinal case study over 15 years provides careful documentation of the types of changes that are required to make improvements over time. In particular, we argue that cultural shifts are an important aspect of sustainable improvements. As we show, even a department that was considered an educational improvement “success story” was unable to sustain the improvements made through its initial effort. Nonetheless, we do argue that the initial effort resulted in shifts to multiple aspects of the department's culture (e.g., ways of thinking, the status of education in the department), that we characterize with Bolman and Deal's four frames. These cultural shifts provided the groundwork for a later effort, to ultimately create sustainable structures in the department resulting in sustained improvement. To conclude, we provide recommendations for how to improve the sustainability of change efforts and describe important methodological considerations for future studies of sustainability.
A New Insight into Non‐Steroidal Anti‐Inflammatory Drugs (NSAIDs) as Modulated Green Inhibitory Agent on Mild Steel Corrosion
Authors: Patel Dhruvi , Makwana Krutarth , Shirdhonkar Manjusha B. , Kuperkar Ketan C.
Published: May 2019

Present study investigate the corrosion inhibition action of green non‐steroidal anti‐inflammatory drugs (NSAIDs) on mild steel (MS) in 1 M HCl by Gravimetric method, Electrochemical Impedance Spectroscopy and Potentiodynamic Tafel polarization at 303.15 K. Changes occurring in the impedance parameters (Rct and Cdl) give clear indication of drug adsorption on the metal surface. Polarization study inferred these drugs to act as a mixed inhibitor. Experimental results inferred a rise in inhibition efficiency with increasing drug concentration. i. e. 90%, 71% and 85% for Aspirin (∼0.3 mM), Diclofenac (∼0.1 mM) and Ibuprofen (∼0.7 mM) respectively. The formation of the Fe‐inhibitor complex and the corrosion inhibition mechanism was inferred by spectral study. Scanning electron microscopy (SEM) and Atomic force microscopy (AFM) gave evidences of the surface topography and proved that the metal surface resist corrosion in presence of inhibitor than in its absence. The degree of hydrophobicity induced due to drug adsorption as obtained by contact angle (CA) is in good agreement with the microscopic results which inferred NSAIDs to act as an effective inhibitor in acidic corrodent. Thermodynamic study confirmed the adsorption process to be spontaneous i. e., ΔG̊ads lies between −17.0 to −20.0 kJ mol−1 which obeyed the Langmuir isotherm. A successive correlation of NSAIDs with their calculated molecular orbital energy levels is well explained using simulation by Density Functional Theory.
A Green Protocol for the Synthesis of α‐Diazo‐β‐hydroxyesters and One‐Pot Conversion to β‐Keto‐Esters and Imidazo[1,2‐a]pyridine‐3‐carboxylates
Authors: Dutta Nibedita Baruah , Sharma Suraj , Chetry Rudra Lal , Baishya Gakul
Published: May 2019

A new solvent cum reagent system comprising of water extract of banana ash and dimethylsulfoxide (WEB‐DMSO) has been engaged for the first time to promote the aldol type condensation reaction of aldehydes with ethyl diazoacetate. The condensation reaction has smoothly undergone producing a range of α‐diazo‐β‐hydroxy esters in good to excellent yields. The solvent system has been reused up to five times without loss of its catalytic activity. Further, two one‐pot sequential reactions have been developed in the same reaction medium. First, the methodology has been extended to synthesize β‐keto esters through Pd catalyzed 1,2‐hydrogen migration. Secondly, β‐keto esters have been converted to imidazo[1,2‐a]pyridine‐3‐carboxylates by using N‐bromosuccinimide and 2‐aminopyridines in a one‐pot fashion.
Silk Composite Electronic Textile Sensor for High Space Precision 2D Combo Temperature–Pressure Sensing
Authors: Wu Ronghui , Ma Liyun , Hou Chen , Meng Zhaohui , Guo Wenxi , Yu Weidong , Yu Rui , Hu Fan , Liu Xiang Yang
Published: May 2019

Wearable electronic textiles based on natural biocompatible/biodegradable materials have attracted great attention due to applications in health care and smart clothes. Silkworm fibers are durable, good heat conductors, insulating, and biocompatible, and are therefore regarded as excellent mediating materials for flexible electronics. In this paper, a strategy on the design and fabrication of highly flexible multimode electronic textiles (E‐textile) based on functionalized silkworm fiber coiled yarns and weaving technology is presented. To achieve enhanced temperature sensing performance, a mixture of carbon nanotubes and an ionic liquid ([EMIM]Tf2N) is embedded, which displays top sensitivity of 1.23% °C−1 and stability compared with others. Furthermore, fibrous pressure sensing based on the capacitance change of each cross‐point of two yarns gives rise to highly position dependent and sensitivity sensing of 0.136 kPa−1. Based on weaving technologies, a unique combo textile sensor, which can sense temperature and pressure independently with a position precision of 1 mm2, is obtained. The application to intelligent gloves endows the position dependent sensing of the weight, and temperature distribution sensing of the temperature.
Study of a new type of replaceable coupling beam in reinforced concrete shear wall structures
Authors: Li Shurong , Jiang Huanjun , He Liusheng
Published: May 2019

It has been found from the past earthquakes that the reinforced concrete coupling beams in tall buildings easily suffer severe damage, which are very difficult to be repaired. To solve this problem, a new type of replaceable coupling beam with a combined damper installed in the middle was proposed in this study. The combined damper consists of an I‐shaped steel beam with multiple low‐yield‐point steel webs paralleled to each other and multiple layers of viscoelastic material bonded between multiple steel plates. The design method of the new replaceable coupling beam was introduced first. Cyclic loading tests on the combined damper were conducted to examine its mechanical behavior. To verify the effectiveness of the new replaceable coupling beam in resisting wind and seismic excitations, two high‐rise building structures, one with traditional coupling beams and the other with the proposed replaceable coupling beams, were designed, and the responses of two structures under the wind and the earthquake were compared with the aid of software Perform‐3D. Compared with the structure with traditional coupling beams, both of the seismic performance and the wind resistance capability of the structure with the proposed replaceable coupling beams are improved significantly.
Descent of fetal head during active pushing: secondary analysis of prospective cohort study investigating ultrasound examination before operative vaginal delivery
Authors: Kahrs B. H. , Usman S. , Ghi T. , Youssef A. , Torkildsen E. A. , Lindtjørn E. , Østborg T. B. , Benediktsdottir S. , Brooks L. , Harmsen L. , Salvesen K. Å. , Lees C. C. , Eggebø T. M.
Published: May 2019

Objectives

To investigate if descent of the fetal head during active pushing is associated with duration of operative vaginal delivery, mode of delivery and neonatal outcome in nulliparous women with prolonged second stage of labor.

Methods

This was a prospective cohort study of nulliparous women with prolonged second stage of labor, conducted between November 2013 and July 2016 in five European countries. Fetal head descent was measured using transperineal ultrasound. Head–perineum distance (HPD) was measured between contractions and on maximum contraction during active pushing, and the difference between these values (ΔHPD) was calculated. The main outcome was duration of operative vaginal delivery, estimated using survival analysis to calculate hazard ratios (HRs) for vaginal delivery, with values > 1 indicating a shorter duration. HR was adjusted for prepregnancy body mass index, maternal age, induction of labor, augmentation with oxytocin and use of epidural analgesia. Pregnancies were grouped according to ΔHPD quartile, and delivery mode and neonatal outcome were compared between groups.

Results

The study population comprised 204 women. Duration of vacuum extraction was shorter with increasing ΔHPD. Estimated mean duration was 10.0, 9.0, 8.8 and 7.5 min in pregnancies with ΔHPD in the first to fourth quartiles, respectively, and the adjusted HR for vaginal delivery, using increasing ΔHPD as a continuous variable, was 1.04 (95% CI, 1.01–1.08). Mean ΔHPD was 7 mm (range, −10 to 37 mm). ΔHPD was either negative or ≤ 2 mm in the lowest quartile. In this group, 7/50 (14%) pregnancies were delivered by Cesarean section, compared with 8/154 (5%) of those with ΔHPD > 2 mm (P < 0.05). There was no significant association between umbilical artery pH < 7.10 or 5‐min Apgar score < 7 and ΔHPD quartile.

Conclusion

Minimal or no fetal head descent during active pushing was associated with longer duration of operative vaginal delivery and higher frequency of Cesarean section in nulliparous women with prolonged second stage of labor. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.
On lepton flavour universality in semileptonic Bc → ηc, J/ψ decays
Authors: Leljak Domagoj , Melić Blaženka , Patra Monalisa
Published: May 2019

Abstract

We discuss B

c
→ η

c
and B

c
→ J/ψ semileptonic decays within the Standard Model (SM) and beyond. The relevant transition form factors, being the main source of theoretical uncertainties, are calculated in the sum rule approach and are provided in a full q
2 range. We calculate the semileptonic branching fractions and find for the ratios,

$$ \left.{R}_{\eta_c}\right|\mathrm{S}\mathrm{M}=0.32\pm 0.02 $$

R

η
c

S
M
=
0.32
±
0.02

, R

J/ψ
|SM = 0.23 ± 0.01. Both predictions are in agreement with other existing calculations and support the current tension in R

J/ψ
at 2σ level with the experiment. To extend the potential of testing the SM in the semileptonic B

c
decays, we consider the forward-backward asymmetry and polarization observables. We also study the 4-fold differential distributions of

$$ {B}_c\to J/\psi \left(J/\psi \to {\tilde{\ell}}^{-}{\tilde{\ell}}^{+}\right){\ell}^{-}{\overline{\nu}}_{\ell } $$

B
c

→
J
/
ψ

J
/
ψ
→

ℓ
˜

−

ℓ
˜

+

ℓ
−

ν
¯

ℓ

, where

$$ \tilde{\ell} = e,\mu $$

ℓ
˜

=
e
,
μ

, in the presence of different new physics scenarios and find that the new physics effects can significantly modify the angular observables and can also produce effects which do not exist in the SM. Using the constraints on the new physics couplings from the recent combined analysis of BaBar, Belle and LHCb data on semileptonic B → D
(∗) decays, where the effects of new physics could be visible, we find that these different new physics scenarios are not able to simultaneously explain the current experimental value of R

J/ψ
.
From topological to quantum entanglement
Authors: Melnikov D. , Mironov A. , Mironov S. , Morozov A. , Morozov An.
Published: May 2019

Abstract

Entanglement is a special feature of the quantum world that reflects the existence of subtle, often non-local, correlations between local degrees of freedom. In topological theories such non-local correlations can be given a very intuitive interpretation: quantum entanglement of subsystems means that there are “strings” connecting them. More generally, an entangled state, or similarly, the density matrix of a mixed state, can be represented by cobordisms of topological spaces. Using a formal mathematical definition of TQFT we construct basic examples of entangled states and compute their von Neumann entropy.
Mirrors without warnings
Authors: Frigg Roman , Nguyen James
Published: May 2019

Veritism, the position that truth is necessary for epistemic acceptability, seems to be in tension with the observation that much of our best science is not, strictly speaking, true when interpreted literally. This generates a paradox: (1) truth is necessary for epistemic acceptability; (2) the claims of science have to be taken literally; (3) much of what science produces is not literally true and yet it is acceptable. We frame Elgin’s project inTrue Enoughas being motivated by, and offering a particular resolution to, this paradox. We discuss the paradox with a focus on scientific models and argue that there is another resolution available which is compatible with retaining veritism: rejecting the idea that scientific models should be interpreted literally.
Functional explanation in mathematics
Authors: Inglis Matthew , Mejía-Ramos Juan Pablo
Published: May 2019

Mathematical explanations are poorly understood. Although mathematicians seem to regularly suggest that some proofs are explanatory whereas others are not, none of the philosophical accounts of what such claims mean has become widely accepted. In this paper we explore Wilkenfeld’s (Synthese 191:3367–3391, 2014) suggestion that explanations are those sorts of things that (in the right circumstances, and in the right manner) generate understanding. By considering a basic model of human cognitive architecture, we suggest that existing accounts of mathematical explanation are all derivable consequences of Wilkenfeld’s ‘functional explanation’ proposal. We therefore argue that the explanatory criteria offered by earlier accounts can all be thought of as features that make it more likely that a mathematical proof will generate understanding. On the functional account, features such as characterising properties, unification, and salience correlate with explanatoriness, but they do not define explanatoriness.
Realism without representationalism
Authors: Rydenfelt Henrik
Published: May 2019

Scientific realism is a critical target of anti-representationalists such as Richard Rorty and Huw Price, who have questioned the very possibility of providing a satisfactory argument for realism or any other ontological position. I will argue that there is a viable form of realism which not only withstands this criticism but is vindicated on the antirepresentationalists’ own grounds. This realist position, largely drawn from the notion of the scientific method developed by the founder of philosophical pragmatism, Charles S. Peirce, will further be compared with the accounts of truth and objectivity proposed by the contemporary pragmatists, Rorty, Price, and Robert B. Brandom.