bluuebunny/crossref_metadata_2025 huggingface dataset:
Study and Analysis of Enclosed Gate FET’s
Authors: Vandana  , Kumar Arvind , Shilla Pooja , Kamal Yadevendra
Published: January 2021

The characteristic and parametric dimensioning of Enclosed Layout (ELT) MOSFET with various geometric sizes and shapes has been taken into consideration for the study of irradiations and leakage at room temperature, which has been confirmed on several technological platforms. Using the most advanced technologies, parametric changes with minimum W/L ratios, layout area and input capacitance to reduce leakage current can improve the performance. The technique of hardening of the MOSFETs in contrary to total-dose radiation effects in space environment built in enclosure to the enclosed transistor for the elimination of edges, responsible of conventional NMOS transistors leakage path creation. High yielding, high level of integration, radiation immune, high speed, low costing and high volume production are the profit advantages of the enclosed layout.
Process capability improvement of an eight-head liquid filling machine by the reduction in volume variation
Authors: Adarsh C K , Kulkarni Sudheer D
Published: January 2021

Filling is the process in which liquid and semi liquid products are filled in a container according to the specified requirement. It has a wide range of importance in various industries like dairy products, oil & lubricants, pharmaceuticals, food and beverages, pesticides, chemicals and cosmetic products. Liquids of low to medium viscosity can be filled using these type of filling machines. Filling machine reduces the operational cost and it is not complex to handle where it contributes in obtaining high rate of liquid production in industries. In this paper filling capability factor of machine in a liquid filling line is studied in terms of statistical process control. Filling capability is increased by the application of total production maintenance. Upon continuous usage, the liquid filling spare parts deteriorate which causes volume variation. Define-Measure-Analyze-Improve-Control (DMAIC) approach is applied to analyze and solve this problem. The root causes for volume variation were identified and effective solutions were implemented to decrease the volume variation and thereby enhance the capability of filling.
Design and Simulation of a Compact 5.4GHz H-shaped Slot Antenna for RF Energy Harvesting Systems
Authors: Nagaraju D. , Gupta Narbada Prasad
Published: January 2021

in this paper, a compact H-shaped slot antenna is proposed. The antenna contains one H-shape slot which is fed through microstrip line, an open circuited stub is connected for proper impedance matching. The H- shaped slot is used for bandwidth enhancement. The antenna is designed to radiate at 5.4 GHz with a bandwidth of 1.6GHz. The antenna has an omni-directional pattern across the frequency band. The gain of the antenna is 4.35dBi at 5.4GHz. Since, the proposed antenna satisfies all the characteristics of energy harvesting systems, it can be used for energy harvesting systems, at 5.4GHz 4G-LTE band. CST microwave studio was used for designing the proposed antenna. An excellent agreement is achieved between simulated and measured results.
Multi-verse optimizer based Fuzzy-PI controller for robust frequency regulation in thermal-hydro power system
Authors: Sharma Mandeep , Dhundhara Sandeep , Singh Surinder , Verma Yajvender Pal
Published: January 2021

This study presents a frequency regulation scheme using a fuzzy-based proportional-integral (FUZZY-PI) controller for two areas non-reheat thermal-hydro power system. Optimal tuning of controller parameters is achieved through a newly established metaheuristic algorithm called Multi-Verse Optimizer (MVO) algorithm. The superiority of the proposed controller has been proven by comparing it with recently published control approaches. The different figure of merits is used to evaluate the performance of the offered controller. The attained results confirm the effectiveness of the designed controller for studied power systems.
Open Loop Trans-conductance Amplifier design for Neural Signals
Authors: Gupta Lipika , Kumar Amod
Published: January 2021

Robust neural recording systems require efficient amplification of weak neural signals at very first stage using Operational Trans-conductance Amplifier (OTA) which should consume minimum power, noise and area. However, there exist a tradeoff for improving the power, noise and area simultaneously. Open loop configuration of OTA has inherent property of lesser area due to absence of feedback; it also provides better noise performance under the given power budget as compared to closed loop counterparts. This paper focuses on the design of Open-loop amplifier OTA topology for non-invasive EEG signals. The simulation results show the improvement in the gain performance of the circuit at 180nm technology node while power and noise of the circuit remains comparable with the existing circuits.
Comparative Study of Optical and Structural Properties of PANI and PANI/CNT Synthesized by Chemical Oxidative Polymerization Method
Authors: Prashar Ankush , Nihal
Published: January 2021

PANI and PANI/CNT have been synthesized by the in-situ chemical oxidation polymerization method. The optical characterization is done by using UV/Vis spectroscopy, FTIR, and PLS. There is a decline in the Absorbance of PANI/CNT as compared to PANI. Similar results have been observed with PL spectra where PANI/CNT has a lower intensity than PANI. The XRD spectra show an increase in intensity for PANI/CNT as compared to PANI. The structural study has been done using the XRD technique. All the results confirm the formation of PANI and PANI/CNT.
Recrystallization of CL-20 to ε-polymorphic form
Authors: Chauhan B S , Thakur A , Soni P K , Kumar M
Published: January 2021

High explosive CL-20 (2,4,6,8,10,12 - Hexanitro - 2,4,6,8,10,12 - hexaazaisowurtzitane) exists in four polymorphic forms i.e. α, β, γ and ε polymorphs at ambient conditions and polymorph ζ exists only at high pressure (1.44 GPa). CL-20 is the only single compound having highest energy among all the organic substances. But polymorphic form α- of CL-20 is generally obtained during most of the synthetic processes which has low density and high sensitivity. Thus, there is requirement of further recrystallization to obtain most stable ε-polymorphic form. Owing to the highest density, superior thermal stability and better insensitivity of ε- polymorph over other three polymorphs (α-, β- and γ- form) which are highly sensitive towards impact, friction and shock, ε- CL-20 is most desirable for use in defence applications. The present work studies the effect of various variables which influence the crystallisation process like effect of moisture, nature of solvent/anti-solvent and time on the preparation of ε- form of CL-20. Ethyl acetate and n-butyl acetate as solvents and toluene as anti-solvent resulted in the formation of desired ε- polymorphic form successfully. Polymorphic form was confirmed by FTIR and XRD analysis. SEM analysis was carried out for the morphological analysis of prepared samples.
Aluminium-Carbon Fibre Metal Matrix Composites: A Review
Authors: Khanna Virat , Kumar Vanish , Bansal Suneev Anil
Published: January 2021

Manufacturing sector always demands superior materials that can cope up with the demand of improved mechanical properties to develop wide applications in diverse sectors. Carbon fibres (CFs) reinforcement in metals matrix is excellent in improving the properties resulting composites. The present review is emphasized on the major developments of using carbon fibres in recent years with aluminium (Al) metal as matrix to improve various mechanical properties. Several aspects (like tensile strength, hardness, shear strength etc.) contributing to the performance of Al-CFs composite have been discussed by covering several case studies. This review reveals that reinforcing CFs in Al matrix increases properties like tensile/shear strength, hardness, wear resistance etc. The mechanism involved in improving these properties is also discussed. Moreover, the remaining challenges in this field and future prospects are discussed in detail.
First Principle Calculations of Effect of Hydrostatic Pressure on Ga0.75Cr0.25P
Authors: Kaur Kirandish , Sharma Suresh
Published: January 2021

In this paper, the investigation of effect of hydrostatic pressure on the structural, electronic and magnetic properties of Ga0.75Cr0.25P ternary alloy in Zinc Blende (B3) phase at 0 GPa to 26 GPa pressure range has been done using first principle calculations as implemented in Spanish Initiative for Electronic Simulations with Thousands of Atoms (SIESTA) code. The theoretical investigation of electronic and magnetic properties of this compound represents that the compound is half-metallic ferromagnet and show 100% spin polarization at different values of pressure. It is found that band gap increases with increase in pressure as spin polarized band structures experience changes with applied pressure. The calculated results show that lattice constant and volume of compound decrease along-with increase in induced local magnetic moments values on non-magnetic gallium and phosphorus atoms with applied pressure.
Recent developments in synthesis, characterization and boiling heat transfer of nanofluids – A Review
Authors: Ravi Babu S , Saras Chandra A , Ramesh Babu P
Published: January 2021

The life of a thermal system depends on how effectively the heat (which is released during its operation), being transferred. Selection of the right fluid is imperative in providing the heat transfer solution for a particular thermal system. Nanofluids are the new generation heat transfer fluids which will give better performance with their superior thermos-physical properties. So much research has been done on nanofluids during the recent years on several aspects like synthesizing the stable nanofluids without losing their properties, characterization, application of nanofluids to forced convection, free convection, boiling heat transfer. The present review is concentrated mainly on the experimental investigations on the preparation and characterization of nanofluids and its applications in several areas. Majority of studies reported that critical heat flux improves with the nanofluids. It will be very useful for the researchers who are about to work on the nanofluids.
Thermodynamic and physiochemical properties and the excess functions of binary mixtures of Dimethylsulfoxide with Pyridine and Nitromethane at variable temperatures - 298 to 318K.
Authors: Kaur Manpreet
Published: January 2021

The density (ρ), viscosity (η), relative permittivity (ε), and ultrasonic velocity (u) in the binary mixture of Dimethylsulfoxide with Pyridine and Nitromethane have been measured at all composition and temperatures 298 K, 308 K, and 318 K. From the experimentally measured values, the excess molar volumes (VE) and the deviation in the viscosities (Δη), relative permittivity (Δε), and ultrasonic velocity (δu) have been correlated. The negative and the positive deviations in the excess functions have been discussed in terms of molecular interactions.
The effects due to a uniformly distributed load in a non-local thermoelastic solid in a frequency domain
Authors: Lata Parveen , Singh Sukhveer
Published: January 2021

In the present study the effects on a non-local thermoelastic solid under the two-dimensional deformation effects due to a uniformly distributed load in a frequency domain have been discussed. The nonlocal thermoelastic solid is homogeneous with the effect of two temperature parameters subjected to uniformly distributed source. Fourier transforms have been used to solve the problem. The analytical expressions of displacement and stress components have been obtained in the transformed domain. For obtaining the results in the physical domain, the numerical inversion technique has been applied. The results so obtained are depicted graphically to show the effect of non-local parameter on the components of displacements and stresses and conductive temperature.
Raman spectroscopy of interfacial transition zone in concrete doped with limestone powder and metakaolin
Authors: Krejcí Kotlanova M , Masek V
Published: January 2021

The interfacial transition zone in concrete with ordinary Portland cement (OPC) and concrete containing OPC and doped with 20% of limestone powder and 30% of metakaolin was studied by Raman spectroscopy - optical profilometry and cluster analysis. Mechanical properties, including strength characteristics and absorbability were tested after 28 days of curing. Concrete with ordinary Portland cement has lower density and absorbability and higher compressive and tensile strength than concrete with limestone powder and metakaolin. It has been found that a large amount of portlandite is formed in the interfacial transition zone in concrete with ordinary Portland cement. In concrete with the addition of metakaolin and limestone powder, the thickness of the interfacial transition zone is reduced, less portlandite is produced, but a thin layer of calcite is formed around quartz grains. This results in lower concrete strength in the area of the interfacial transition zone.
The external renders of the early 20th century architecture
Authors: Tislova R , Svoboda P , Vsiansky D
Published: January 2021

External renders are an essential part of the architecture of the first half of the 20th century. The aesthetic effect of such plasterwork was achieved by surface treatment, colouring or by using various filler components that acted with their colour or structure. The binder of the plasters was most often Portland cement which played an important role in the processing of plasters or surface finishes, and in addition, formed the functional properties of the plasters (hardness, durability, resistance to external conditions).

This paper summarizes the results of a survey focused on the characterization of components used for the creation of external rendering taken from several architecturally significant buildings in the city of Brno dating back to the first half of the 20th century (villas, apartment buildings, public apartment houses). The survey into the collected samples performed by means of petrographic (light polarizing microscopy) and phase (powder X-ray diffraction) analysis revealed interesting information concerning the wide range of materials (components) used and the craftsmanship involved in their processing, all of which fundamentally influence the art-craft and utility properties of the buildings. The information gathered can serve as an important source of information for the renovation of early 20th century architecture.
Impedance spectroscopy measurement of metakaolin-based alkali-activated building materials
Authors: Kusak I , Lunak M , Mizerova C , Rovnanik P
Published: January 2021

Cement-containing as well as cement-free building materials are regarded as dielectrics. Therefore, electrically conducting admixtures are to be added to them in order to increase their electrical conductivity. Steel or carbon fibres, metal powder, graphite, carbon soot or carbon nanotubes are commonly used for this purpose. The conductivity increase offers new application options, such as sensor property materials, self-heated materials, or electromagnetic smog shielding materials. The specimens of the mixes to be studied were subjected to an electrical analysis carried out within the frequency range from 100 MHz to 3 GHz by means of an ZNC vector analyser and an SPEAG-made DAK-12 coaxial probe and, furthermore, a dedicated automatically measuring device operating within the frequency range from 40 Hz to 1 MHz. The frequency spectra of interest were measured on various copolymer specimens differing from each other by the content of graphite and carbon nanotubes. Higher content of these admixtures increases the electrical conductivity and the building materials thus become easier to measure by means of electromagnetic measuring methods.
Instrumented dynamic tests of building materials
Authors: Sperl M , Gajdos L’ , Slizkova Z , Drdlova M
Published: January 2021

In some specific cases, the building structures can be exposed to extreme dynamic loads. Namely, it can be car crash, earthquake or the effect of explosion. For these cases, it is useful to know the dynamic mechanical properties of building materials. The paper presents two unique procedures for instrumented impact testing of building materials (concrete and sandstone). These tests may help in practice with selection of suitable materials for buildings and structures which may be threatened by dynamic effects of mechanical stresses. The method how to achieve a higher dynamic material stability is also presented.
The study on corrosion behavior and corrosion resistance of ultralow carbon high silicon iron-based alloy
Authors: Zhang Yue , Xiao Jun , Zhang Yishun , Liu Wei , Pei Wei , Zhao Aimin , Zhang Wei , Zeng Li
Published: January 2021

The ultralow carbon high silicon iron-based alloy (sample A) with a single ferrite matrix was prepared. The corrosion performance difference and mechanism between it and conventional high silicon cast iron (sample B) were systematically studied using optical microscope, scanning electron microscope, electric corrosion equipment, electrochemical corrosion workshop and atomic force microscope. The results show that the corrosion rate of ultralow carbon iron-based alloys was significantly lower than that of high-silicon cast iron. For example, the static corrosion rate after 310 h, the corrosion rate of sample A was 0.2399 g/(m2 · h), and the corrosion rate of sample B was 1.5159 g/(m2 · h). The potential difference of the substrate was significantly reduced. That is, the ultralow carbon iron-based alloy exhibits better corrosion resistance, which is mainly attributed to the denser passivation film formed on its surface. The results of microhardness show that the hardness of Sample A was higher than that of Sample B.
Arterial Endothelial Function and Related Factors in Elderly Patients With Essential Hypertension and Abdominal Obesity
Authors: Huang He-ling , Shen Yi-hua , Cai Xiao-qi , Zhang Ling-yu , Xie Liang-di
Published: January 2021

Background

To investigate arterial endothelial function and related factors in elderly patients with both essential hypertension and abdominal obesity.

Methods

A total of 658 elderly patients (≥60 years old) with essential hypertension and 64 elderly subjects without hypertension were recruited. Hypertension and obesity were defined based on blood pressure (≥140/90 mm Hg) and waist circumference (male ≥90, female ≥85 cm), respectively. Endothelium-dependent dilatation (EDD) of anterior tibial artery induced by reactive hyperemia was examined by high-resolution vascular ultrasound. Pearson correlation analysis, factorial analysis, and multiple linear regression analysis were undertaken to examine the related factors of EDD.

Results

Factorial analysis showed that hypertension and abdominal obesity were influence factors of EDD, but there was no interaction between them. From normotensive without abdominal obesity, normotensive with abdominal obesity, hypertensive without abdominal obesity, to hypertensive with abdominal obesity, a gradual decline in EDD was observed (9.37 ± 1.11%, 8.59 ± 0.99%, 7.70 ± 0.30%, and 6.75 ± 0.26%, respectively, P < 0.05). In elderly hypertensive patients with abdominal obesity, EDD correlated with waist circumference (r = −0.139, P < 0.05), systolic blood pressure (r = −0.245, P < 0.05), pulse pressure (r = −0.287, P < 0.05), and fasting glucose level (r = −0.131, P < 0.05). Multivariate linear regression analysis revealed that EDD was associated with pulse pressure (β = −0.280, P < 0.001) and waist circumference (β = − 0.141, P = 0.009).

Conclusions

In elderly patients with essential hypertension and central obesity, EDD is impaired, and negatively correlated with pulse pressure and waist circumference.
Umbrella of protection: spatial and temporal dynamics in a temperate butterfly Batesian mimicry system
Authors: Prusa Louis A , Hill Ryan I
Published: January 2021

Batesian mimicry involves both spatial and temporal interactions between model, mimic and predator. Fundamental predictions in Batesian mimicry involve space, time and abundance; specifically, that the model and mimic are found in sympatry and that protection for the mimic is increased when predators interact with the model first and more frequently. Research has generally confirmed these predictions for Batesian mimicry at large spatial scales, with recent work on two nymphalid butterflies in western North America, the mimic Limenitis lorquini (Boisduval, 1852) and its model Adelpha californica (Butler, 1865) in western North America indicating that the mimic generally has lower abundance and emerges later in the season among widely separated populations in the California Coast Ranges and Sierra Nevada. However, no studies have investigated model–mimic dynamics at small scales in the temperate zone to test whether temporal habitat use and movements conform to predictions. If mimicry is as important a part of the biology of these temperate species as it is for their tropical counterparts, then in addition to emerging later and being less abundant overall, the mimic should be less widespread, should be less abundant in each habitat and should move less among available habitats. Our results using mark–release–recapture methods confirm these predictions and indicate that the mimic, L. lorquini, is enjoying an umbrella of protection against habitat specialist and generalist predators alike.
Testing calibration of phenotyping models using positive-only electronic health record data
Authors: Zhang Lingjiao , Ma Yanyuan , Herman Daniel , Chen Jinbo
Published: January 2021

Validation of phenotyping models using Electronic Health Records (EHRs) data conventionally requires gold-standard case and control labels. The labeling process requires clinical experts to retrospectively review patients’ medical charts, therefore is labor intensive and time consuming. For some disease conditions, it is prohibitive to identify the gold-standard controls because routine clinical assessments are performed for selective patients who are deemed to possibly have the condition. To build a model for phenotyping patients in EHRs, the most readily accessible data are often for a cohort consisting of a set of gold-standard cases and a large number of unlabeled patients. Hereby, we propose methods for assessing model calibration and discrimination using such “positive-only” EHR data that does not require gold-standard controls, provided that the labeled cases are representative of all cases. For model calibration, we propose a novel statistic that aggregates differences between model-free and model-based estimated numbers of cases across risk subgroups, which asymptotically follows a Chi-squared distribution. We additionally demonstrate that the calibration slope can also be estimated using such “positive-only” data. We propose consistent estimators for discrimination measures and derive their large sample properties. We demonstrate performances of the proposed methods through extensive simulation studies and apply them to Penn Medicine EHRs to validate two preliminary models for predicting the risk of primary aldosteronism.
Hepatocellular carcinoma progression during bridging before liver transplantation
Authors: Renner P , Da Silva T , Schnitzbauer A A , Verloh N , Schlitt H J , Geissler E K
Published: January 2021

Background

Recipient selection for liver transplantation in hepatocellular carcinoma (HCC) is based primarily on criteria affecting the chance of long-term success. Here, the relationship between pretransplant bridging therapy and long-term survival was investigated in a subgroup analysis of the SiLVER Study.

Methods

Response to bridging, as defined by comparison of imaging at the time of listing and post-transplant pathology report, was categorized into controlled versus progressive disease (more than 20 per cent tumour growth or development of new lesions).

Results

Of 525 patients with HCC who had liver transplantation, 350 recipients underwent pretransplant bridging therapy. Tumour progression despite bridging was an independent risk factor affecting overall survival (hazard ratio 1.80; P = 0.005). For patients within the Milan criteria (MC) at listing, mean overall survival was longer for those with controlled versus progressive disease (6.8 versus 5.8 years; P < 0.001). Importantly, patients with HCCs outside the MC that were downsized to within the MC before liver transplantation had poor outcomes compared with patients who never exceeded the MC (mean overall survival 6.2 versus 6.6 years respectively; P = 0.030).

Conclusion

Patients with HCCs within the MC that did not show tumour progression under locoregional therapy had the best outcomes after liver transplantation. Downstaging into the limits of the MC did not improve the probability of survival.

Prognostic factors determining the long-term success of liver transplantation in patients with hepatocellular carcinoma are still under discussion. A subgroup analysis of the SiLVER trial showed that disease control under bridging therapy is strongly associated with improved prognosis in terms of overall survival. However, in tumours exceeding the limits of the Milan criteria, downstaging did not restore the probability of survival compared with that of patients within the Milan criteria.
Traumatic injury is associated with reduced deoxyribonuclease activity and dysregulation of the actin scavenging system
Authors: Hazeldine Jon , Dinsdale Robert J , Naumann David N , Acharjee Animesh , Bishop Jonathan R B , Lord Janet M , Harrison Paul
Published: January 2021

Background

Traumatic injury is associated with increased concentrations of cell-free DNA (cfDNA) in the circulation, which contribute to post-injury complications. The endonuclease deoxyribonuclease 1 (DNase-1) is responsible for removing 90% of circulating cfDNA. Recently, DNase activity was reported to be significantly reduced following major non-traumatic brain injury (TBI), but the processes responsible were not investigated. Moreover, it is not known how quickly following injury DNase activity is reduced and whether this also occurs after TBI.

Methods

At 3 post-injury time points (≤1, 4–12 and 48–72 hours), blood samples were obtained from 155 adult trauma patients that had sustained an isolated TBI (n = 21), TBI with accompanying extracranial injury (TBI+) (n = 53) or an extracranial injury only (ECI) (n = 81). In addition to measuring cfDNA levels and the activity and expression of DNase, circulating concentrations of monomeric globular action (G-actin), an inhibitor of DNase-1, and the actin scavenging proteins gelsolin (GSN) and vitamin D binding protein (VDBP) were determined and values compared to a cohort of healthy controls.

Results

Significantly elevated concentrations of plasma cfDNA were seen in TBI, TBI+ and ECI patients at all study time points when compared to healthy controls. cfDNA levels were significantly higher at ≤1 hour post-injury in ECI patients who subsequently developed multiple organ dysfunction syndrome when compared to those who did not. Plasma DNase-1 protein was significantly elevated in all patient groups at all sampling time points. In contrast, DNase enzyme activity was significantly reduced, with this impaired function evident in TBI+ patients within minutes of injury. Circulating concentrations of G-actin were elevated in all patient cohorts in the immediate aftermath of injury and this was accompanied by a significant reduction in the levels of GSN and VDBP.

Conclusions

The post-traumatic increase in circulating cfDNA that occurs following extracranial trauma and TBI is accompanied by reduced DNase activity. We propose that, secondary to reduced GSN and VDBP levels, elevated circulating concentrations of G-actin underlie the post-injury reduction in DNase activity. Reducing circulating cfDNA levels via therapeutic restoration of DNase-1 activity may improve clinical outcomes post-injury.
Examining the Boundary Sharpness Coefficient as an Index of Cortical Microstructure in Autism Spectrum Disorder
Authors: Olafson Emily , Bedford Saashi A , Devenyi Gabriel A , Patel Raihaan , Tullo Stephanie , Park Min Tae M , Parent Olivier , Anagnostou Evdokia , Baron-Cohen Simon , Bullmore Edward T , Chura Lindsay R , Craig Michael C , Ecker Christine , Floris Dorothea L , Holt Rosemary J , Lenroot Rhoshel , Lerch Jason P , Lombardo Michael V , Murphy Declan G M , Raznahan Armin , Ruigrok Amber N V , Spencer Michael D , Suckling John , Taylor Margot J ,   MRC AIMS Consortium, Lai Meng-Chuan , Chakravarty M Mallar
Published: January 2021

Autism spectrum disorder (ASD) is associated with atypical brain development. However, the phenotype of regionally specific increased cortical thickness observed in ASD may be driven by several independent biological processes that influence the gray/white matter boundary, such as synaptic pruning, myelination, or atypical migration. Here, we propose to use the boundary sharpness coefficient (BSC), a proxy for alterations in microstructure at the cortical gray/white matter boundary, to investigate brain differences in individuals with ASD, including factors that may influence ASD-related heterogeneity (age, sex, and intelligence quotient). Using a vertex-based meta-analysis and a large multicenter structural magnetic resonance imaging (MRI) dataset, with a total of 1136 individuals, 415 with ASD (112 female; 303 male), and 721 controls (283 female; 438 male), we observed that individuals with ASD had significantly greater BSC in the bilateral superior temporal gyrus and left inferior frontal gyrus indicating an abrupt transition (high contrast) between white matter and cortical intensities. Individuals with ASD under 18 had significantly greater BSC in the bilateral superior temporal gyrus and right postcentral gyrus; individuals with ASD over 18 had significantly increased BSC in the bilateral precuneus and superior temporal gyrus. Increases were observed in different brain regions in males and females, with larger effect sizes in females. BSC correlated with ADOS-2 Calibrated Severity Score in individuals with ASD in the right medial temporal pole. Importantly, there was a significant spatial overlap between maps of the effect of diagnosis on BSC when compared with cortical thickness. These results invite studies to use BSC as a possible new measure of cortical development in ASD and to further examine the microstructural underpinnings of BSC-related differences and their impact on measures of cortical morphology.
Tracking oxy-thermal habitat compression encountered by Chesapeake Bay striped bass through acoustic telemetry
Authors: Itakura Hikaru , O’Brien Michael H P , Secor David
Published: January 2021

In many coastal ecosystems, habitat compression is caused by seasonal combinations of hypoxia and supraoptimal temperatures. These conditions commonly induce avoidance behaviours in mobile species, resulting in the concentrated use of marginal habitats. Using 3 years of acoustic telemetry and high-resolution water quality data recorded throughout Chesapeake Bay, we measured the seasonal movements and exposure of striped bass (Morone saxatilis) to oxy-thermal habitat compression. Striped bass moved to tidal freshwaters in spring (March–May), mesohaline waters in summer (June–August) and fall (September–November), and mesohaline and polyhaline waters in winter (December–February): seasonal patterns consistent with known spawning, foraging, and overwintering migrations. Analyses of habitat selection suggest that during conditions of prevalent sub-pycnocline hypoxia (June–September), striped bass appeared to select surface waters (i.e. they may avoid bottom hypoxic waters). Striped bass detections indicated tolerance of a wide range of surface water temperatures, including those >25°C, which regional regulatory bodies stipulate are stressful for this species. Still, during summer and fall striped bass selected the lowest-available temperature and avoided water temperature >27°C, demonstrating that Chesapeake Bay striped bass can encounter habitat compressions due to the behavioural avoidance of bottom hypoxia and high temperatures.
Asset Pricing with Endogenous Beliefs-Dependent Risk Aversion
Authors: Ouysse Rachida
Published: January 2021

I present an economy where aggregate risk aversion is stochastic, exogenous, and beliefs-dependent. The preferences are conditionally isoelastic álaGordon and St-Amour (2004). Representative consumer forms expectations about aggregate aversion to growth states’ uncertainty and makes beliefs-contingent consumption and investment decisions. The consumer is rewarded for preferences risk in addition to consumption risk. The consumer’s attitudes toward uncertainty about the business cycle are countercyclical, mildly volatile, with volatility clustering in periods of economic bust. When evaluated on cross-sections of stock returns, the model generates economically small unconditional Euler errors. This article presents new evidence that conditioning on a data rich information filtration leads to substantial pricing improvements. There is increased volatility and clustering around recessions in information poor environment.
Struma ovarii in bilateral ovarian teratoma—case report and literature review
Authors: Leite Cláudia , Rodrigues Pedro , Oliveira Susana Lima , Martins Nuno Nogueira , Martins Francisco Nogueira
Published: January 2021

Struma ovarii is an uncommon ovarian tumour, defined by the finding of thyroid tissue in the ovary, and more frequently found in teratomas. Symptoms of struma ovarii are nonspecific. The definite diagnosis is made by histological examination. The authors report the case of an asymptomatic 76-year-old female patient, whose ultrasonography, magnetic resonance and computed tomography suggested bilateral ovarian teratoma. Risk of Ovarian Malignancy Assessment score was high. She underwent exploratory laparotomy, peritoneal washing, total hysterectomy, bilateral adnexectomy and intra-operative frozen section. The final pathological report described bilateral mature cystic teratoma with benign struma ovarii. Surgery remains the best treatment.
Black swans, dragon kings and the uncertainty in international nuclear law
Authors: Handrlica Jakub
Published: January 2021

Black swans and dragon kings both represent metaphors for extremely large adverse events with tremendous impact on society and industry. However, while dragon kings refer to those harmful events, which are predictable to some degree, black swans are a surprise because the consequence of them far exceeds what anyone had previously estimated, even using sophisticated risk analysis of low probability events. Nuclear accidents in Chernobyl and Fukushima represent salient examples of black swans. This article aims to address how international nuclear law copes with dragon kings and how black swans may impact existing legal framework on peaceful uses of nuclear energy worldwide.
SAMHD1 restrains aberrant nucleotide insertions at repair junctions generated by DNA end joining
Authors: Akimova Ekaterina , Gassner Franz Josef , Schubert Maria , Rebhandl Stefan , Arzt Claudia , Rauscher Stefanie , Tober Vanessa , Zaborsky Nadja , Greil Richard , Geisberger Roland
Published: January 2021

Aberrant end joining of DNA double strand breaks leads to chromosomal rearrangements and to insertion of nuclear or mitochondrial DNA into breakpoints, which is commonly observed in cancer cells and constitutes a major threat to genome integrity. However, the mechanisms that are causative for these insertions are largely unknown. By monitoring end joining of different linear DNA substrates introduced into HEK293 cells, as well as by examining end joining of CRISPR/Cas9 induced DNA breaks in HEK293 and HeLa cells, we provide evidence that the dNTPase activity of SAMHD1 impedes aberrant DNA resynthesis at DNA breaks during DNA end joining. Hence, SAMHD1 expression or low intracellular dNTP levels lead to shorter repair joints and impede insertion of distant DNA regions prior end repair. Our results reveal a novel role for SAMHD1 in DNA end joining and provide new insights into how loss of SAMHD1 may contribute to genome instability and cancer development.
Effective Containment of a COVID-19 Subregional Outbreak in Italy Through Strict Quarantine and Rearrangement of Local Health Care Services
Authors: Tedeschi Sara , Badia Lorenzo , Berveglieri Fabio , Ferrari Rodolfo , Coladonato Simona , Gabrielli Sabrina , Maestri Antonio , Peroni Gabriele , Giannella Maddalena , Rossi Andrea , Viale Pierluigi ,   COVID-19 Fighting Team, Acanto Alessandra , Battistoni Alessandra , Bendanti Nicoletta , Dalfiume Giancarlo , Fina Antonella , Gardenghi Emanuela , Giulianini Sofia , Grassi Bianca , Neretti Anna , Prantoni Silvia , Zanotti Paola , Zoffoli Lorenza , Assirelli Carlotta , Barilli Gabriele , Brozyna Marta Sylwia , Cafaro Michele , Capoccia Francesco , Momeni Lise Chekam , Contarino Giuseppe , Contos Giorgio , Kanj Mounzer , Krawczyk Alessia , Manara Francesca , Puica Alina
Published: January 2021

Background

Since the beginning of the pandemic, the epidemiology of coronavirus disease 2019 (COVID-19) in Italy has been characterized by the occurrence of subnational outbreaks. The World Health Organization recommended building the capacity to rapidly control COVID-19 clusters of cases in order to avoid the spread of the disease. This study describes a subregional outbreak of COVID-19 that occurred in the Emilia Romagna region, Italy, and the intervention undertaken to successfully control it.

Methods

Cases of COVID-19 were defined by a positive reverse transcriptase polymerase chain reaction (RT-PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on nasopharyngeal swab. The outbreak involved the residential area of a small town, with ~10 500 inhabitants in an area of 9 km2. After the recognition of the outbreak, local health care authorities implemented strict quarantine and a rearrangement of health care services, consisting of closure of general practitioner outpatient clinics, telephone contact with all residents, activation of health care units to visit at-home patients with symptoms consistent with COVID-19, and a dedicated Infectious Diseases ambulatory unit at the nearest hospital.

Results

The outbreak lasted from February 24 to April 6, 2020, involving at least 170 people with a cumulative incidence of 160 cases/10 000 inhabitants; overall, 448 inhabitants of the municipality underwent at least 1 nasopharyngeal swab to detect SARS-CoV-2 (positivity rate, 38%). Ninety-three people presented symptoms before March 11 (pre-intervention period), and 77 presented symptoms during the postintervention period (March 11–April 6).

Conclusions

It was possible to control this COVID-19 outbreak by prompt recognition and implementation of a targeted local intervention.
A mixed-linkage (1,3;1,4)-β-D-glucan specific hydrolase mediates dark-triggered degradation of this plant cell wall polysaccharide
Authors: Kraemer Florian J , Lunde China , Koch Moritz , Kuhn Benjamin M , Ruehl Clemens , Brown Patrick J , Hoffmann Philipp , Göhre Vera , Hake Sarah , Pauly Markus , Ramírez Vicente
Published: January 2021

The presence of mixed-linkage (1,3;1,4)-β-d-glucan (MLG) in plant cell walls is a key feature of grass species such as cereals, the main source of calorie intake for humans and cattle. Accumulation of this polysaccharide involves the coordinated regulation of biosynthetic and metabolic machineries. While several components of the MLG biosynthesis machinery have been identified in diverse plant species, degradation of MLG is poorly understood. In this study, we performed a large-scale forward genetic screen for maize (Zea mays) mutants with altered cell wall polysaccharide structural properties. As a result, we identified a maize mutant with increased MLG content in several tissues, including adult leaves and senesced organs, where only trace amounts of MLG are usually detected. The causative mutation was found in the GRMZM2G137535 gene, encoding a GH17 licheninase as demonstrated by an in vitro activity assay of the heterologously expressed protein. In addition, maize plants overexpressing GRMZM2G137535 exhibit a 90% reduction in MLG content, indicating that the protein is not only required, but its expression is sufficient to degrade MLG. Accordingly, the mutant was named MLG hydrolase 1 (mlgh1). mlgh1 plants show increased saccharification yields upon enzymatic digestion. Stacking mlgh1 with lignin-deficient mutations results in synergistic increases in saccharification. Time profiling experiments indicate that wall MLG content is modulated during day/night cycles, inversely associated with MLGH1 transcript accumulation. This cycling is absent in the mlgh1 mutant, suggesting that the mechanism involved requires MLG degradation, which may in turn regulate MLGH1 gene expression.
Working on the Frontlines of the COVID-19 Pandemic: A Qualitative Study of Physical Therapists’ Experience in Spain
Authors: Palacios-Ceña Domingo , Fernández-de-las-Peñas César , Palacios-Ceña María , de-la-Llave-Rincón Ana I , Florencio Lidiane L
Published: January 2021

Objective

Knowledge of the experiences of health care professionals who have actively worked on the first line of the COVID-19 pandemic could help to identify specific professional duties focused on health assistance objectives. No qualitative study has yet been published, to our knowledge, describing the experience of physical therapists during the COVID-19 pandemic. The purpose of this study was to describe and explore the experiences and perspectives of physical therapists working in public hospitals in Madrid, Spain, during the COVID-19 pandemic.

Methods

A qualitative exploratory study was conducted based on an interpretive framework. Thirty physical therapists working at 11 national public hospitals during the COVID-19 outbreak were recruited by purposeful sampling and snowball techniques. In-depth interviews and researchers’ field notes were used to collect data. Interviews were transcribed verbatim. Inductive thematic analysis was used to identify emerging themes.

Results

After identifying 3912 codes and 13 categories, 3 themes emerged. The first theme was “call of duty”; as COVID-19 infection dramatically spread, the hospitals were contaminated and overwhelmed, and all floors were converted into COVID-19 wards. The second theme was “working in war time.” Every day, therapists were given “the war report,” receiving their orders, meeting protective personal equipment requirements, and confronting fear. The third theme was “when I arrive at home.” Working during the pandemic had an impact on the therapists’ families and the information shared with them.

Conclusions

Physical therapists described the COVID-19 outbreak as an apocalyptic and unexpected war. Comprehensive support is needed for all frontline health care professionals. The COVID-19 outbreak revealed that health care systems were not prepared for a pandemic.

Impact

To our knowledge, this is the first qualitative study to be published describing the experience of physical therapists during the COVID-19 pandemic.
On the spectral asymptotics of waves in periodic media with Dirichlet or Neumann exclusions
Authors: Oudghiri-Idrissi Othman , Guzina Bojan B , Meng Shixu
Published: January 2021

We consider homogenization of the scalar wave equation in periodic media at finite wavenumbers and frequencies, with the focus on continua characterized by: (a) arbitrary Bravais lattice in $\mathbb{R}^d$, $d \geqslant 2$, and (b) exclusions, that is, ‘voids’ that are subject to homogeneous (Neumann or Dirichlet) boundary conditions. Making use of the Bloch-wave expansion, we pursue this goal via asymptotic ansatz featuring the ‘spectral distance’ from a given wavenumber-eigenfrequency pair (situated anywhere within the first Brillouin zone) as the perturbation parameter. We then introduce the effective wave motion via projection(s) of the scalar wavefield onto the Bloch eigenfunction(s) for the unit cell of periodicity, evaluated at the origin of a spectral neighborhood. For generality, we account for the presence of the source term in the wave equation and we consider—at a given wavenumber—generic cases of isolated, repeated, and nearby eigenvalues. In this way, we obtain a palette of effective models, featuring both wave- and Dirac-type behaviors, whose applicability is controlled by the local band structure and eigenfunction basis. In all spectral regimes, we pursue the homogenized description up to at least first order of expansion, featuring asymptotic corrections of the homogenized Bloch-wave operator and the homogenized source term. Inherently, such framework provides a convenient platform for the synthesis of a wide range of intriguing wave phenomena, including negative refraction and topologically protected states in metamaterials and phononic crystals. The proposed homogenization framework is illustrated by approximating asymptotically the dispersion relationships for (i) Kagome lattice featuring hexagonal Neumann exclusions and (ii) square lattice of circular Dirichlet exclusions. We complete the numerical portrayal of analytical developments by studying the response of a Kagome lattice due to a dipole-like source term acting near the edge of a band gap.
Central sensitization, illness perception and obesity should be considered when interpreting disease activity in axial spondyloarthritis
Authors: Kieskamp Stan C , Paap Davy , Carbo Marlies J G , Wink Freke , Bos Reinhard , Bootsma Hendrika , Arends Suzanne , Spoorenberg Anneke
Published: January 2021

Objectives

Many patients with axial spondyloarthritis (axSpA) report persistent pain even when treated with anti-inflammatory agents. Our aim was to explore the presence of central sensitization (CS) and different types of illness perceptions in patients with axSpA, and to assess their associations with disease activity assessments.

Methods

Consecutive outpatients from the Groningen Leeuwarden Axial Spondyloarthritis (GLAS) cohort were included. Besides standardized assessments, patients filled out the Central Sensitization Inventory (CSI), Illness Perception Questionnaire (IPQ-R) and Pain Catastrophizing Scale (PCS). Univariable and multivariable linear regression analyses were used to investigate the association between questionnaire scores, patient characteristics and disease activity assessments ASDASCRP, BASDAI and CRP.

Results

We included 182 patients with a mean symptom duration of 21.6 years. Mean ASDASCRP was 2.1, mean BASDAI 3.9, and median CRP 2.9. Mean CSI score was 37.8 (scale 0–100) and 45% of patients scored ≥40, indicating a high probability of CS. CSI score, IPQ-R domain identity (number of symptoms the patient attributes to their illness), and IPQ-R domain treatment control (perceived treatment efficacy), and obesity were significantly and independently associated with both ASDASCRP and BASDAI, explaining a substantial proportion of variation in these disease activity scores (R2=0.35 and R2=0.47, respectively). Only obesity was also independently associated with CRP.

Conclusion

CS may be common in patients with long-term axSpA. CS, as well as specific illness perceptions and obesity were all independently associated with the widely used (partially) patient-reported disease activity assessments ASDASCRP and BASDAI. Treating physicians should take this into account in the follow-up and treatment of their patients.