bluuebunny/crossref_metadata_2025 huggingface dataset:
A rat H1t‐GFP transgene recapitulates endogenous H1t expression pattern in mouse
Authors: Lipschutz Emma , Dasgupta Anindya , Guan Yongjuan , Kistler W. Stephen , Wang P. Jeremy
Published: January 2020

H1 histones bind to linker DNA. H1t (H1f6), a testis‐specific linker histone variant, is present in pachytene spermatocytes and spermatids. The expression of H1t histone coincides with the acquisition of metaphase I competence in pachytene spermatocytes. Here we report the generation of H1t‐GFP transgenic mice. The H1t‐GFP (H1 histone testis‐green fluorescence protein) fusion protein expression recapitulates the endogenous H1t expression pattern. This protein appears first in mid pachytene spermatocytes in stage V seminiferous tubules, persists in round spermatids and elongating spermatids, but is absent in elongated spermatids. The strong green fluorescence signal, due to the high abundance of H1t‐GFP, is maintained in spermatocytes after induction towards metaphase I through treatment with okadaic acid. Therefore, H1t‐GFP can be used as a visual marker for monitoring the progression of meiosis in vitro and in vivo, as well as fluorescence‐activated cell sorting (FACS) sorting of germ cells.
What's in a band? The function of the color and banding pattern of the Banded Swallowtail
Authors: Tan Eunice J. , Wilts Bodo D. , Tan Brent T. K. , Monteiro Antónia
Published: January 2020

Butterflies have evolved a diversity of color patterns, but the ecological functions for most of these patterns are still poorly understood. The Banded Swallowtail butterfly, Papilio demolion demolion, is a mostly black butterfly with a greenish‐blue band that traverses the wings. The function of this wing pattern remains unknown. Here, we examined the morphology of black and green‐blue colored scales, and how the color and banding pattern affects predation risk in the wild. The protective benefits of the transversal band and of its green‐blue color were tested via the use of paper model replicas of the Banded Swallowtail with variations in band shape and band color in a full factorial design. A variant model where the continuous transversal green‐blue band was shifted and made discontinuous tested the protective benefit of the transversal band, while grayscale variants of the wildtype and distorted band models assessed the protective benefit of the green‐blue color. Paper models of the variants and the wildtype were placed simultaneously in the field with live baits. Wildtype models were the least preyed upon compared with all other variants, while gray models with distorted bands suffered the greatest predation. The color and the continuous band of the Banded Swallowtail hence confer antipredator qualities. We propose that the shape of the band hinders detection of the butterfly's true shape through coincident disruptive coloration; while the green color of the band prevents detection of the butterfly from its background via differential blending. Differential blending is aided by the green‐blue color being due to pigments rather than via structural coloration. Both green and black scales have identical structures, and the scales follow the Bauplan of pigmented scales documented in other Papilio butterflies.
Health effects of reduced workload for older employees
Authors: Bratberg Espen , Holmås Tor Helge , Monstad Karin
Published: January 2020

To keep elder employees in the labour force, introducing age‐dependent job conditions can be a policy measure. However, we know little about the effect of such initiatives. We investigate the effects of a particular programme in Norway that reduces the workload of teachers at age 55 but maintains the same wage. Evaluation of this programme is well suited to a difference‐in‐difference analysis, where the control group is teachers slightly too young to be eligible for the workload reduction. Using full population register data for the period 2006–2013, we analyse the effects of the programme on health as indicated by sickness absence and health care utilization. We find that whereas there is no effect among women, the workload reduction causes a decrease in sickness absence and an improvement in mental health among males. These results, which are robust to a placebo test, to extending the pretreatment period, and to dropping single birth cohorts, are driven by a subgroup of men whose prior health status is poor.
Modeling rectal cancer to advance neoadjuvant precision therapy
Authors: Janakiraman Harinarayanan , Zhu Yun , Becker Scott A. , Wang Cindy , Cross Ashley , Curl Emily , Lewin David , Hoffman Brenda J. , Warren Graham W. , Hill Elizabeth G. , Timmers Cynthia , Findlay Victoria J. , Camp Ernest R.
Published: January 2020

Progress in rectal cancer therapy has been hindered by the lack of effective disease‐specific preclinical models that account for the unique molecular profile and biology of rectal cancer. Thus, we developed complementary patient‐derived xenograft (PDX) and subsequent in vitro tumor organoid (PDTO) platforms established from preneoadjuvant therapy rectal cancer specimens to advance personalized care for rectal cancer patients. Multiple endoscopic samples were obtained from 26 Stages 2 and 3 rectal cancer patients prior to receiving 5FU/RT and implanted subcutaneously into NSG mice to generate 15 subcutaneous PDXs. Second passaged xenografts demonstrated 100% correlation with the corresponding human cancer histology with maintained mutational profiles. Individual rectal cancer PDXs reproduced the 5FU/RT response observed in the corresponding human cancers. Similarly, rectal cancer PDTOs reproduced significant heterogeneity in cellular morphology and architecture. PDTO in vitro 5FU/RT treatment response replicated the clinical 5FU/RT neoadjuvant therapy pathologic response observed in the corresponding patient tumors (p < 0.05). The addition of cetuximab to the 5FU/RT regiment was significantly more sensitive in the rectal cancer PDX and PDTOs with wild‐type KRAS compared to mutated KRAS (p < 0.05). Considering the close relationship between the patient's cancer and the corresponding PDX/PDTO, rectal cancer patient‐derived research platforms represent powerful translational research resources as population‐based tools for biomarker discovery and experimental therapy testing. In addition, our findings suggest that cetuximab may enhance RT effectiveness by improved patient selection based on mutational profile in addition to KRAS or by developing a protocol using PDTOs to identify sensitive patients.
Ultra‐structural analysis of human spermatozoa by aperture scanning near‐field optical microscopy
Authors: Troian Barbara , Boscolo Rita , Ricci Giuseppe , Lazzarino Marco , Zito Gabriella , Prato Stefano , Andolfi Laura
Published: January 2020

Scanning near‐field optical microscopy (SNOM) represents a potential candidate for investigation of ultrastructure in human spermatozoa. It is a noninvasive optical technique that offers two main advantages: minimal sample preparation and simultaneous topographical and optical images acquisition with a spatial resolution beyond the diffraction limit. This enables the combination of surface characterization and information from the inner cellular organization in a single acquisition providing an immediate and comprehensive analysis of the cellular portions. In this work spermatozoa are immobilized on poly‐L‐lysine coated coverslips, fixed according to a standard protocol and imaged by aperture‐SNOM in air. In the SNOM images, all peculiar sperm portions show well‐resolved optical features, which exhibit good similarities with the structures revealed in transmission electron microscopy images, as compared with literature data. The optical features of anomalous spermatozoa are clearly different as respect with those observed for healthy ones. This analysis reveals the potentialities of SNOM and opens to its application to high‐resolution analysis of sperm morphological alterations, which might be relevant in reproductive medicine.
Synthesis and bio‐evaluation of novel 2‐arylquinoxaline
Authors: Gundlewad Gangadhar B. , Patil Bhagwan. R.
Published: January 2020

2‐Arylquinoxalines were synthesized by the condensation of α‐chloroacetophenone and o‐phenylenediamine (1:1) using pyridine as catalyst in THF at room temperature. All the compounds were characterized by spectral data. Furthermore, these are screened for in vivo anti‐inflammatory activity by carrageenan induced rat hind paw edema methods all the compounds were displayed significant anti‐inflammatory activity. The title compounds were also shown good antibacterial and antifungal activity.
Synthesis and characterization of novel 2‐(1‐benzyl‐3‐[4‐fluorophenyl]‐1H‐pyrazol‐4‐yl)‐7‐fluoro‐4H‐chromen‐4‐one derivatives
Authors: Hon Kiran S. , Akolkar Hemantkumar N. , Karale Bhausaheb K.
Published: January 2020

Novel 1‐benzyl‐3‐(4‐fluorophenyl)‐1H‐pyrazole‐4‐carbaldehydes 3a to 3e were synthesized via Vilsmeier‐Haack reaction of the appropriate 1‐benzyl‐2‐(1‐(4‐fluorophenyl)ethylidene)hydrazines, derived from 4‐fluoroacetophenone 1 with substituted 2‐benzylhydrazines 2a to 2e. The base catalyzed condensation of 1‐benzyl‐3‐(4‐fluorophenyl)‐1H‐pyrazole‐4‐carbaldehydes 3a to 3e with 1‐(4‐fluoro‐2‐hydroxyphenyl)ethanone 4 gave (E)‐3‐(1‐benzyl‐3‐(4‐fluorophenyl)‐1H‐pyrazol‐4‐yl)‐1‐(4‐fluoro‐2‐hydroxyphenyl)prop‐2‐en‐1‐ones 5a to 5e. On cyclization with dimethyl sulfoxide (DMSO)/I2, compounds 5a to 5e gave 2‐(1‐benzyl‐3‐(4‐fluorophenyl)‐1H‐pyrazol‐4‐yl)‐7‐fluoro‐4H‐chromen‐4‐ones 6a to 6e. Structures of all novel compounds were confirmed by infrared (IR), proton nuclear magnetic resonance (1H NMR), carbon nuclear magnetic resonance (13C NMR), and mass spectral data. All the synthesized compounds were screened for their antibacterial activities.
Misdiagnosis of CTX due to propofol: The interference of total intravenous propofol anaesthesia with bile acid profiling
Authors: Claesen Joep L. A. , Koomen Erik , Schene Imre F. , Jans Judith J. M. , Mast Natalia , Pikuleva Irina A. , van der Ham Maria , de Sain‐van der Velden Monique G. M. , Fuchs Sabine A.
Published: January 2020

Background

Cerebrotendinous xanthomatosis (CTX) is a rare genetic disorder, characterised by chronic diarrhoea, xanthomas, cataracts, and neurological deterioration. CTX is caused by CYP27A1 deficiency, which leads to abnormal cholesterol and bile acid metabolism. Urinary bile acid profiling (increased m/z 627: glucuronide‐5β‐cholestane‐pentol) serves as diagnostic screening for CTX. However, this led to a false positive CTX diagnosis in two patients, who had received total intravenous anaesthesia (TIVA) with propofol.

Methods

To determine the influence of propofol on bile acid profiling, 10 urinary samples and 2 blood samples were collected after TIVA with propofol Fresenius 7 to 10 mg/kg/h from 12 subjects undergoing scoliosis correction. Urinary bile acids were analysed using flow injection negative electrospray mass spectrometry. Propofol binding to recombinant CYP27A1, the effects of propofol on recombinant CYP27A1 activity, and CYP27A1 expression in liver organoids were investigated using spectral binding, enzyme activity assays, and qPCR, respectively. Accurate masses were determined with high‐resolution mass spectrometry.

Results

Abnormal urinary profiles were identified in all subjects after TIVA, with a trend correlating propofol dose per kilogramme and m/z 627 peak intensity. Propofol only induced a weak CYP27A1 response in the spectral binding assay, minimally affected CYP27A1 activity and did not affect CYP27A1 expression. The accurate mass of m/z 627 induced by propofol differed >10 PPM from m/z 627 observed in CTX.

Conclusions

TIVA with propofol invariably led to a urinary profile misleadingly suggestive of CTX, but not through CYP27A1 inhibition. To avoid further misdiagnoses, propofol administration should be considered when interpreting urinary bile acid profiles.
Genetics of age‐related hearing loss
Authors: Wells Helena Rose Rees , Newman Tracey A. , Williams Frances M. K.
Published: January 2020

Age‐related hearing loss (ARHL) has recently been confirmed as a common complex trait, that is, it is heritable with many genetic variants each contributing a small amount of risk, as well as environmental determinants. Historically, attempts to identify the genetic variants underlying the ARHL have been of limited success, relying on the selection of candidate genes based on the limited knowledge of the pathophysiology of the condition, and linkage studies in samples comprising related individuals. More recently genome‐wide association studies have been performed, but these require very large samples having consistent and reliable phenotyping for hearing loss (HL), and early attempts suffered from lack of reliable replication of their findings. Replicated variants shown associated with ARHL include those lying in genes GRM7, ISG20, TRIOBP, ILDR1, and EYA4. The availability of large biobanks and the development of collaborative consortia have led to a breakthrough over the last couple of years, and many new genetic variants associated with ARHL are becoming available, through the analysis publicly available bioresources and electronic health records. These findings along with immunohistochemistry and mouse models of HL look set to help disentangle the genetic architecture of ARHL, and highlight the need for standardization of phenotyping methods to facilitate data sharing and collaboration across research networks.
Growth and Clinical Outcome in Very Low‐Birth‐Weight Infants After the Introduction of a Multicomponent Intravenous Lipid Emulsion
Authors: Hill Nicole S. , Cormack Barbara E. , Little Bridget S. , Bloomfield Frank H.
Published: January 2020

Background

Very low‐birth‐weight (VLBW; birth weight < 1500 g) infants are often dependent on intravenous nutrition after birth. Conventional soy‐based intravenous lipid emulsions (Soy LE) are associated with inflammatory and metabolic complications that may be harmful to preterm infants. Evidence to support any clinical benefit associated with newer multicomponent emulsions (Mixed LE), remains inconsistent and unsubstantiated in appropriate studies. This retrospective study aimed to determine whether growth and clinical outcomes differed between VLBW infants given Mixed LE vs Soy LE at Auckland City Hospital.

Methods

Data were collected on nutrition, growth, and neonatal morbidities for the first 4 weeks after birth. Outcomes were compared between 2 lipid cohorts, Soy LE (February 2013 – August 2014) and Mixed LE (August 2014 – December 2015), using univariate and multivariate analysis.

Results

207 infants (Soy LE, 105 vs Mixed LE, 102) were included in the study. Significantly fewer infants in the Mixed LE cohort developed any stage retinopathy of prematurity (Soy LE 59% vs Mixed LE 39%, P = .005) or intraventricular hemorrhage (Soy LE 27% vs Mixed LE 15%, P = .03) during their admission. Mixed LE was also associated with significantly lower mean (P = .01), minimum (P = .03), and maximum (P = .04) total bilirubin concentrations across the first 4 weeks after birth. There was no difference in growth velocity or weight, length, and head circumference z‐score change.

Conclusion

SMOFlipid may represent a favorable alternative to conventional lipid emulsions in neonatal parenteral nutrition regimens; however, long‐term effects should be further evaluated.
Passivated‐electrode insulator‐based dielectrophoretic separation of heterogeneous cell mixtures
Authors: Kikkeri Kruthika , Kerr Bethany A. , Bertke Andrea S. , Strobl Jeannine S. , Agah Masoud
Published: January 2020

Rapid and accurate purification of various heterogeneous mixtures is a critical step for a multitude of molecular, chemical, and biological applications. Dielectrophoresis has shown to be a promising technique for particle separation due to its exploitation of the intrinsic electrical properties, simple fabrication, and low cost. Here, we present a geometrically novel dielectrophoretic channel design which utilizes an array of localized electric fields to separate a variety of unique particle mixtures into distinct populations. This label‐free device incorporates multiple winding rows with several nonuniform structures on to sidewalls to produce high electric field gradients, enabling high locally generated dielectrophoretic forces. A balance between dielectrophoretic forces and Stokes’ drag is used to effectively isolate each particle population. Mixtures of polystyrene beads (500 nm and 2 μm), breast cancer cells spiked in whole blood, and for the first time, neuron and satellite glial cells were used to study the separation capabilities of the design. We found that our device was able to rapidly separate unique particle populations with over 90% separation yields for each investigated mixture. The unique architecture of the device uses passivated‐electrode insulator‐based dielectrophoresis in an innovative microfluidic device to separate a variety of heterogeneous mixture without particle saturation in the channel.
Magnetic solid‐phase extraction method for extraction of some pesticides in vegetable and fruit juices
Authors: Farajzadeh Mir Ali , Safi Razieh , Yadeghari Adeleh
Published: January 2020

A new version of magnetic solid‐phase extraction performed in a narrow‐bore tube has been proposed for the extraction and preconcentration of different pesticides from various vegetable and fruit juices followed by gas chromatography. A few milligrams of C8@SiO2@Fe3O4 nanoparticles are added into an aqueous sample solution placed in a narrow‐bore tube. The sorbent particles move down through the tube under gravity and are collected at the end of the tube by applying an external magnetic field. The end of the tube is narrower and it is connected to a stopcock. After a predetermined time, the stopcock is opened and the solution is passed through the bed of the sorbent maintained by the magnet. Then the adsorbed analytes are desorbed using an elution solvent. To achieve high enrichment factors, a dispersive liquid–liquid microextraction method is carried out. The nanoparticles were characterized by scanning electron microscopy, X‐ray diffraction, and FTIR spectroscopy. Under the optimum extraction conditions, limits of detection and quantification were in the ranges of 0.1–0.3 and 0.3–0.9 μg/L, respectively. High enrichment factors (1166–1605) and good extraction recoveries (58–80%) were obtained.
A novel interstitial deletion of chromosome 2q21.1‐q23.3: Case report and literature review
Authors: Almuzzaini Bader , Alatwi Nasser S. , Alsaif Saif , Al Balwi Mohammed A.
Published: January 2020

Background

Interstitial deletions of 2q are rare. Those that have been reported show varying clinical manifestations according to the size of the deletion and the genomic region involved.

Method and Results

We describe a preterm male harboring a novel interstitial deletion encompassing the 2q21.2‐q23.3 region of 2q, a deletion that has not been described previously. The patient had multiple congenital anomalies including agenesis of the corpus callosum, congenital cardiac defects, bilateral hydronephrosis, spontaneous intestinal perforation, hypospadias and cryptorchidism, sacral dimple and rocker‐bottom feet. Array comparative genomic hybridization (aCGH) analysis revealed a de novo >18 Mb deletion at 2q21.1–q23.3, a region that included (605802, 611472 and 604593) OMIM genes.

Conclusion

To the best of our knowledge this is the first report of a de novo interstitial deletion at 2q21.1–q23.3 in which haploinsufficiency of dose‐sensitive genes is shown to contribute to the patient's phenotype.
Impact of transverse magnetic fields on dose response of a radiophotoluminescent glass dosimeter in megavoltage photon beams
Authors: Ito Shotaro , Araki Fujio , Ohno Takeshi
Published: January 2020

Purpose

The purpose of this study was to investigate the impact of transverse magnetic fields on the dose response of a radiophotoluminescent glass dosimeter (RGD) in megavoltage photon beams.

Methods

The RGD relative response (i.e., RGD dose per absorbed dose to water at the midpoint of the detector in the absence of the detector) was calculated using Monte Carlo (MC) simulations. Note that the Monte Carlo calculations do not account for changes of the signal production per unit dose to the RGD caused by the magnetic field strength. The relative energy response RQ, the relative magnetic response RB, and the relative overall response RQ,B with the transverse magnetic fields of 0–3 T were analyzed as a function of depth, for a 10 cm × 10 cm field in a solid water phantom, for 4–18 MV photons. Although magnetic resonance (MR) linacs with flattening filter free beams are commercially available, flattening filter beams were used to investigate the RGD response in this study. RQ is the response in beam quality Q relative to that in the reference beam with quality 6 MV, RB is the response in beam quality Q with the magnetic field relative to that in beam quality Q without the magnetic field, and the RQ,B is the response in beam quality Q with the magnetic field relative to that in the reference beam with quality 6 MV without the magnetic field. Two RGD orientations were considered: RGD long axis is parallel (direction A) and perpendicular (direction B) to the magnetic field. The reference irradiation conditions were at the depth of 10 cm for a 10 cm × 10 cm field for 6 MV, without the magnetic field. In addition, the influence of a small air‐gap between the holder inner wall and the RGD on the dose response in the magnetic field, Rgap, was analyzed in detail. Rgap is the response in beam quality Q without/with the air‐gap.

Results

RQ decreased by up to 2.7% as the energy increased in the range of 4–18 MV, except in the buildup region. In direction A, the variation of RB owing to the magnetic field strength was below 1.0%, regardless of the photon energy. In contrast, in direction B, RB decreased with increasing magnetic field strength and decreased up to 4.0% at 3 T for 10 MV. The Rgap for 0.03 and 0.05 cm air‐gap models in direction A decreased up to 2.3% and up to 4.0%, respectively.

Conclusions

The variation of RQ,B changed with the direction of the RGD relative to the magnetic field. For dose measurements, RGDs should be positioned with the long axis parallel to the magnetic field, without air‐gaps.
30% Ethanol Locks Are Effective in Preventing Central Line–Associated Bloodstream Infections in Pediatric Intestinal Failure: A Pilot Study
Authors: Vanegas Calderon Oriana , Rahhal Riad
Published: January 2020

Background

Complications related to central venous lines (CVLs) are common in intestinal failure (IF), including central line–associated bloodstream infections (CLABSIs). Replacing heparin with 70% ethanol locks can reduce infection rates; however, concerns exist about potential negative effects on catheter integrity. We hypothesized that a lower ethanol concentration combined with citrate would prevent catheter‐related complications, including CLABSIs.

Methods

This was a retrospective cohort study in pediatric IF patients assessing rates of CLABSIs, catheter repair, catheter replacement, and thrombolytic (alteplase) use for suspected catheter‐related thromboses comparing heparin, 70% ethanol, and 30% ethanol–2.8% citrate locks.

Results

Six patients were included with a total of 8777 catheter days. All patients utilized silicone single‐lumen CVLs for venous access. The rate of CLABSIs was highest with heparin at 13.9 events per 1000 catheter days, which significantly dropped to 1.6 per 1000 catheter days on 70% ethanol (P = .02) and remained significantly low at 0.4 per 1000 catheter days when transitioning to 30% ethanol–2.8% citrate locks as compared with heparin (P = .01). No statistically significant differences were noted among the groups in rates of catheter repair and replacement and alteplase use.

Conclusion

This pilot study provides supportive evidence that a lower ethanol lock concentration may be effective in maintaining a low rate of CLABSIs in pediatric IF patients using silicone CVLs. Although this study did not show significant positive impact on catheter integrity and durability, there are other potential benefits to using lower ethanol concentrations including reduced systemic ethanol exposure in children.
Primal column generation framework for vehicle and crew scheduling problems
Authors: Himmich Ilyas , El Hallaoui Issmail , Soumis François
Published: January 2020

The primal adjacency‐based algorithm and the multidirectional dynamic programming algorithm are two exact methods that have recently been developed to efficiently solve the shortest path problem with resource constraints (SPPRCs). These methods are primal in the sense that they are able to produce sequences of feasible solutions using iterative exploration of the search space. Since the SPPRCs often appear as a subproblem (SP) in the solution of vehicle and crew scheduling problems (VCSP) using column generation (CG), we propose a new primal column generation framework that embeds these primal methods in a CG scheme. The primal column generation solves at each iteration a sequence of appropriate restricted SP and stops solving the SP when there is no need to continue. This approach introduces a large degree of flexibility, and allows performing good cost improvements in a very limited time. Computational experiments on VCSP instances show that the proposed approach is able to find optimal solutions while reducing the time spent solving the SP by factors of up to seven compared to the standard CG algorithm. This leads to significant improvements in the overall solution times, with an average reduction factor of 3.5.
Nanoparticle‐Reinforced Silica Gels with Enhanced Mechanical Properties and Excellent pH‐Sensing Performance
Authors: Xie Xinyuan , Deng Yingshi , Peng Jiehui , Zheng Shiqi , Cao Chezheng , Xie Weiguo , Li Xiaochun
Published: January 2020

Silica gels offer excellent wear resistance, high chemical stability, good insulation, and light transmittance, are therefore promising to engineer 2D sensing films. However, their practical applications are greatly hampered by their poor structural stability, low sensitivity, reliability, and repeatability. Incorporation of nanoelements into glasses and ceramics is a promising new pathway to tackle these challenges. Unfortunately, it is difficult to disperse nanoparticles uniformly in any glass and ceramics. Herein, a facile sol–gel approach is applied to synthesize novel silica gel nanocomposites with dispersed nanoparticles (NPs) as additives and thymol blue as an indicator. Titanium dioxide (TiO2) NPs with a diameter of 5 nm can be dispersed uniformly in the silica gel, with enhanced modulus and hardness (up to 230% and 138%, respectively) and good alkaline resistance. The addition of nanoparticles improves the film's stability, sensitivity, and repeatability of spectral responses (in pH 1–12), and reduces the indicator leakage. The interaction of indicator with silica gel substrate, nanoparticles, and H+ is analyzed to elucidate the principle of reversible color change. This novel simplified method to produce glass‐like functional materials under much lower temperatures is groundbreaking in materials science and engineering.
Void Collapse in Shocked ‐HMX Single Crystals: Simulations and Experiments
Authors: Duarte Camilo A. , Hamed Ahmed , Drake Jonathan D. , Sorensen Christian J. , Son Steven F. , Chen Weynong W. , Koslowski Marisol
Published: January 2020

Heat generation in the vicinity of a void during shock compression plays a key role in the initiation of energetic materials. The shock response of a single
‐HMX crystal with a single void is studied with simulations that include plasticity and heat transport. The numerical results are validated with an experiment in which a 500
m void is machined in an HMX single crystal and impacted. Experiments and simulations of the dynamical evolution of the morphology of the void during the collapse and the rate of the area are in very good agreement for weak shocks.
Comparative Study of Characteristics and Interface States with and without Post‐Gate‐Annealing Treatment for AlGaN/GaN‐Recessed Metal–Insulator–Semiconductor High Electron Mobility Transistors Using HfO2 Gate Insulator on Si Substrates
Authors: Zhao Yaopeng , Wang Chong , Zheng Xuefeng , Ma Xiaohua , He Yunlong , Liu Kai , Li Ang , Peng Yue , Zhang Chunfu , Hao Yue
Published: January 2020

Three types of enhancement‐mode (E‐mode) AlGaN/GaN metal–insulator–semiconductor high electron mobility transistors (MIS‐HEMTs) with different barrier depths are fabricated on Si substrates. A HfO2 gate insulator with a thickness of 30 nm is grown by plasma‐enhanced atomic layer deposition (PEALD) at 300 °C. The drain current density and transconductance increase greatly after post‐gate‐annealing (PGA, 400 °C, 5 min) treatment. The Vth of the MIS‐HEMT decreases after PGA treatment and the C–V characteristics are a good match to the Vth change of the transfer characteristics. The interface states are in the form of trap states and fixed charges. The trap states at the HfO2/AlGaN interface are measured by the frequency‐ and voltage‐dependent conductivity method. The trap state density and time constant decrease after the PGA treatment. The fixed charge density can be calculated by the Vth shift. According to the calculation results, the fixed charge density also decreases. The PGA treatment can reduce the interface state density effectively and is a significant process for the gate‐recessed MIS‐HEMT.
A novel quantification of information for longitudinal data analyzed by mixed‐effects modeling
Authors: Yuan Min , Li Yi , Yang Yaning , Xu Jinfeng , Tao Fangbiao , Zhao Liang , Zhou Honghui , Pinheiro Jose , Xu Xu Steven
Published: January 2020

Nonlinear mixed‐effects (NLME) modeling is one of the most powerful tools for analyzing longitudinal data especially under the sparse sampling design. The determinant of the Fisher information matrix is a commonly used global metric of the information that can be provided by the data under a given model. However, in clinical studies, it is also important to measure how much information the data provide for a certain parameter of interest under the assumed model, for example, the clearance in population pharmacokinetic models. This paper proposes a new, easy‐to‐interpret information metric, the “relative information” (RI), which is designed for specific parameters of a model and takes a value between 0% and 100%. We establish the relationship between interindividual variability for a specific parameter and the variance of the associated parameter estimator, demonstrating that, under a “perfect” experiment (eg, infinite samples or/and minimum experimental error), the RI and the variance of the model parameter estimator converge, respectively, to 100% and the ratio of the interindividual variability for that parameter and the number of subjects. Extensive simulation experiments and analyses of three real datasets show that our proposed RI metric can accurately characterize the information for parameters of interest for NLME models. The new information metric can be readily used to facilitate study designs and model diagnosis.
Observations and high‐resolution simulations of convective precipitation organization over the tropical Atlantic
Authors: Brune Sebastian , Buschow Sebastian , Friederichs Petra
Published: January 2020

High‐resolution simulations (grid spacing 2.5 km) are performed with ICON‐LEM to characterize convective organization in the Tropics during August 2016 over a large domain ranging from northeastern South America, along the tropical Atlantic to Africa (8,000×3,000 km). The degree of organization is measured by a refined version of the wavelet‐based organization index (WOI), which is able to characterize the scale, the intensity and anisotropy of convection based on rain rates alone. Exploiting the localization of wavelets both in space and time, we define a localized version of the convective organization index (LWOI). We compare convection observed in satellite‐derived rain rates with the corresponding processes simulated by ICON‐LEM. Model and observations indicate three regions with different kinds of convective organization. Continental convection over West Africa has a predominantly meridional orientation and is more organized than over South America, because it acts on larger scales and is more intense. Convection over the tropical Atlantic is zonally oriented along the ITCZ and less intense. ICON and observations agree on the number and intensity of the African easterly waves during the simulation period. The waves are associated with strong vorticity anomalies and are clearly visible in a spatiotemporal wavelet analysis. The central speed and the wavelength of the waves is simulated well. Both the scale and intensity components of LWOI in ICON are significantly correlated with environmental variables. The scale of precipitation is related to wind shear, CAPE and its tendency, while the intensity strongly correlates with column‐integrated humidity, upper‐level divergence and maximum vertical wind speed. This demonstrates that the LWOI components capture important characteristics of convective precipitation.
Transoral robotic narrow field oropharyngectomy for tumours of the parapharyngeal space
Authors: Sethi Neeraj , Dale Oliver , Vidhyadharan Sivakumar , Krishnan Suren , Foreman Andrew , Hodge JC
Published: January 2020

The advent of transoral robotic surgery (TORS) has allowed transoral approaches for parapharyngeal space (PPS) tumours to be re‐evaluated. It provides enhanced visualisation and instrument access for appropriate tumours. We describe a specific technique, TORS narrow‐field oropharyngectomy, that is ideal for benign PPS tumours which have been violated by intra‐oral biopsy or incision and drainage. This allows the contaminated, overlying oropharyngeal mucosa to be resected en‐bloc with the PPS tumour, reducing the risk of local recurrence. This technique provides a window into the PPS, improving visualisation of underlying neurovascular structures as well as the tumour. This reduces the risk of tumour spillage and leads to superior vascular access and haemorrhage control. This technique is only applicable to PPS tumours that are appropriate for transoral approaches and is specifically designed for those selected patients that have been placed at risk of seeding or local scarring by intra‐oral procedures prior to definitive resection. We present two such cases: a 38‐year‐old male with a PPS inflammatory cyst and a 66‐year‐old female with a PSS pre‐styloid Schwannoma.
What it takes to be hunky
Authors: Giberman Daniel ,   Philosophy Documentation Center
Published: January 2020

A world is gunky iff every object that exists according to it has others as proper parts. A world is junky iff every object that exists according to it is a proper part of some others. Several philosophers have followed (Bohn, 2009a) in then saying that a world is “hunky” just in case it is both gunky and junky. The present note explains a need to clarify the determinative criteria for being hunky. It then provides the needed clarification and explains why the issue, though subtle, is not merely pedantic.
Reduction of erythromycin resistance gene erm(F) and class 1 integron‐integrase genes in wastewater by Bardenpho treatment
Authors: Schmitz Bradley W. , Innes Gabriel K. , Xue Jia , Gerba Charles P. , Pepper Ian L. , Sherchan Samendra
Published: January 2020

Wastewaters routinely contain antibiotic‐resistant bacteria (ARB) and genes (ARG) that are removed to a varying degree during wastewater treatment. This study investigated the removal of the erythromycin ribosome methylase class F (erm(F)) and class 1 integron‐integrase (intI1) genes at each stage from two water resource recovery facilities in southern Arizona. Although genes were significantly reduced by Bardenpho treatment, erm(F) and intI1 were still observed in ≥ 9 and 7 out of 12 secondary effluent samples. Primary processes via sedimentation or dissolved air flotation, as well as chlorine disinfection, did not significantly impact erm(F) and intI1 concentrations. Therefore, Bardenpho treatment was critical to reduce erm(F) and intI1. Concentrations of erm(F) and intI1 were compared with each other and other markers for anthropogenic pollution. Results from this study support intI1 as one suitable marker to measure erythromycin resistance genes in wastewater, as intI1 was found at higher concentrations, persisted more throughout treatment, and correlated with erm(F) at nearly every treatment stage.

Practitioner points

Bardenpho treatment was the key process responsible for the reduction of intI1 and erm(F) genes during wastewater treatment.

Primary treatment and chlorine disinfection did not impact erm(F) and intI1 gene concentrations.

The intI1 gene is a suitable marker for measuring erm(F) genes in wastewater.
Band‐reject‐filtering X‐ray spectra by mosaic structures of pyrolytic graphite
Authors: Turyanskiy Alexander G. , Gizha Sergey S.
Published: January 2020

The possibility of effective band‐reject filtration of intense spectral lines in X‐ray spectra and the creation of deep spectral valleys in the continuous spectrum by diffraction extinction was shown. Optimum material for band‐reject filters in the energy rangeE > 6 keV is highly oriented pyrolytic graphite (HOPG). The filtering scheme in the form of an echelon arrangement of HOPG films is proposed, which suppresses the negative effect of multiple reflections due to diffraction extinction. The full width at half minimum of the spectral valleys can vary from tens of electronvolt to several kiloelectron volt depending on the HOPG mosaic spread, HOPG filters arrangement, and rejected energy region. At the energy rangeEof ~10 keV, the spectral density attenuation value may be of order 10−3and lower. The obtained results can be used in various fields of X‐ray spectrometry, as well as in static energy dispersive diffractometry and reflectometry.
Influence of System Performance on Layer Thickness Determination Using Terahertz Time-Domain Spectroscopy
Authors: Weber Stefan , Liebelt Lukas , Klier Jens , Pfeiffer Tobias , Molter Daniel , Ellrich Frank , Jonuscheit Joachim , Freymann Georg Von
Published: January 2020

The quality of coatings in industrial applications and scientific research with thicknesses in the micrometer range is an important criterion for quality management. Therefore, thickness determination devices are of high interest. Terahertz time-domain spectroscopy systems have demonstrated the capability to address thickness determination of dielectric single- and multilayer coatings on different substrates. However, due to the large range of different samples, there are different performance requirements to ensure a high-quality determination result. In this paper, we investigate the influence of system parameters—bandwidth and dynamic range—on thickness determination performance for a single-layer coating on metal substrates with thicknesses from 0.5 to 100 pm, based on measurements and numerical calculations within dynamic ranges from 10 to 90 dB and bandwidths from 1.5 to 10 THz.
A mechanistic insight into defluoridation of simulated wastewater applying bio-inspired sodium alginate bead
Authors: Thakre Prashil N. , Mukherjee Shraboni , Samanta Sucharita , Barman Sanghamitra , Halder Gopinath
Published: January 2020

The experiment successfully investigated fluoride (F−) uptake capacity of bio-inspired sodium alginate bead (BISAB) using ZSM-5 as an adsorbent through a series of batch studies. The study conducted to observe impact of individual parameter on F− adsorption reveals pH and adsorbent dose to have dominant effect in BISAB uptake as compared to time and temperature. Adsorbent prepared from ZSM-5 with high surface area and micropore volume can adsorb 92% of fluoride at optimized condition. Langmuir, Freundlich, D–R and Tempkin isotherms have been studied for fluoride adsorption. Among all models, Langmuir isotherm fitted exceptionally well over other models; this can be concluded from the regression coefficient obtained for Langmuir model which was very close to 1. The kinetic study suggests F− adsorption onto prepared BISAB to follow pseudo-second-order kinetics of average rate constant 6.5475×10−4 g/fluoride per min. Thermodynamic parameters ΔH°, ΔS° and ΔG° were found to be 10.167 kJ/mol, 29.35 J/mol and − 4.71 to − 13.4444 kJ/mol, respectively. The fluoride adsorption onto BISAB was endothermic reaction.
Estimation of reservoir porosity using analysis of seismic attributes in an Iranian oil field
Authors: Soleimani Fatemeh , Hosseini Erfan , Hajivand Farzad
Published: January 2020

The most commonly used data for reservoir description are well and seismic data. Well data such as logs typically provide sufficient vertical resolution but leave a large space between the wells. Three-dimensional seismic data, on the other hand, can provide more detailed reservoir characterization between wells. However, the vertical resolution of seismic data is poor compared with that of well data. Conventionally, seismic data have been used to delineate reservoir structure; however, seismic data can be used for reservoir characterization such as porosity. Therefore, we can combine these two types of data to obtain reservoir parameters such as porosity and saturation. It is available the desired parameter (such as porosity) of the number of wells in the reservoir and seismic cube. And we are looking for the parameter estimation in the whole reservoir. To do this, there are several methods including multiple linear regression, neural networks, and geostatistical methods. Therefore, by determining the reservoir properties and correctly estimating these parameters, optimization can be performed with fewer wells, and the costs of exploration and production are reduced. In this paper, we apply these methods on the available data for an oil field in southwest Iran to obtain the porosity in a total reservoir cube, and these methods are then compared with one another. The results clearly show the superiority of neural networks compared with the other methods in estimating the reservoir parameter. The results also show that although estimation accuracy is increased significantly with the use of the geostatistical approach, this method requires that a sufficient number of well logs, representing all the fields under investigation, be provided in order to improve the geological model obtained by the multi-attribute and neural network methods.
Population Pyramids Yield Accurate Estimates of Total Fertility Rates
Authors: Hauer Mathew E. , Schmertmann Carl P.
Published: January 2020

The primary fertility index for a population, the total fertility rate (TFR), cannot be calculated for many areas and periods because it requires disaggregation of births by mother’s age. Here we discuss a flexible framework for estimating TFR using inputs as minimal as a population pyramid. We develop five variants, each with increasing complexity and data requirements. We test accuracy across a diverse set of data sources that comprise more than 2,400 fertility schedules with known TFR values, including the Human Fertility Database, Demographic and Health Surveys, U.S. counties, and nonhuman species. We show that even the simplest and least accurate variant has a median error of only 0.09 births per woman over 2,400 fertility schedules, suggesting accurate TFR estimation over a wide range of demographic conditions. We anticipate that this framework will extend fertility analysis to new subpopulations, periods, geographies, and even species. To demonstrate the framework’s utility in new applications, we produce subnational estimates of African fertility levels, reconstruct historical European TFRs for periods up to 150 years before the collection of detailed birth records, and estimate TFR for the United States conditional on race and household income.
Design and fabrication of runaway probe for studying the behavior of runaway electrons in IR-T1 Tokamak
Authors: Afsari Taher , Ghoranneviss Mahmood , Meshkani Sakineh , Ghanbari Mohammad Reza
Published: January 2020

Several theoretical and experiential studies of runaway electrons in the well-known Tokamaks of the world have been made over the past few decades. In the present study, the measurements of runaway electrons energy were carried out by a new runaway probe in the IR-T1 Tokamak.
In the IR-T1 Tokamak, the hard X-ray diagnostic system is used as a diagnostic global measurement system at the vessel wall of Tokamak. Runaway probe was first designed and fabricated for local measurement near the plasma edge in IR-T1 Tokamak. The new diagnostic has the advantage that the local interaction of runaways with materials can be evaluated, along with the direct measurement of the runaway electrons. The runaway probe consists of 2 LYSO (Lu 1.8Y.2SiO5:Ce) crystals covered by a graphite housing which is shielded by tungsten filter placed in the direction of runaway electrons. The main elements of the runaway probe are LYSO crystals which convert the energy of runaway electrons into visible light which is instructed to silicon photomultipliers. The present study aimed to evaluate a new runaway probe in the IR-T1 Tokamak to detect beta and gamma rays. The results indicated that electron spectrum is between 500 keV and 2 MeV at the plasma edge in the IR-T1 Tokamak.
Dimensionen und Ausprägungen fachinhaltlicher Kompetenz in den Naturwissenschaften – ein Systematisierungsversuch
Authors: Vorholzer Andreas , von Aufschnaiter Claudia
Published: January 2020

In den letzten ca. 15 Jahren haben die Modellierung und die Erfassung von Kompetenz im deutschen Sprachraum eine wichtige Rolle gespielt. Es wurde eine große Vielfalt von Kompetenzmodellen entwickelt, die auch dann unterschiedliche Dimensionen und Ausprägungen beschreiben, wenn sie auf den gleichen Kompetenzbereich Bezug nehmen. Ein zentrales Anliegen des Beitrages ist es, exemplarisch an einem kleinen Ausschnitt aus dem Forschungsfeld – der Modellierung fachinhaltlicher Kompetenz von Schüler*innen in den Naturwissenschaften – vorliegende Modelle (überwiegend aus dem deutschsprachigen Raum) aufeinander zu beziehen und dabei insbesondere die Varianz in den Dimensionierungen der Modelle herauszuarbeiten. Mithilfe induktiver Kategorienbildung wurden aus der Analyse bestehender Modelle sieben verschiedene Hauptdimensionen rekonstruiert, die im Beitrag erläutert werden: (1) Inhalt, (2) Kontext, (3) Vernetzung, (4) Denkprozess, (5) Abstraktion, (6) Angemessenheit und (7) Eigenständigkeit. Es wird diskutiert, welche Erträge diese systematische Perspektive für die Einordnung von Forschungsarbeiten im Bereich der Modellierung und Messung fachinhaltlicher Kompetenz hat und welche Herausforderungen und Fragestellungen sich aus dieser Perspektive für zukünftige Forschungsarbeiten ergeben. Dabei wird u. a. in den Blick genommen, inwiefern sich sowohl das methodische Vorgehen als auch die von uns rekonstruierten Dimensionen auf andere Bereiche naturwissenschaftlicher Kompetenz (z. B. KompetenzbereichErkenntnisgewinnung) und andere Zielgruppen (z. B. Studierende) übertragen lassen.