bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and characterization of triangular hollow porous polyacrylonitrile fiber made by coaxial wet spinning
Authors: Wang Huiyun , Wang Ping , Zhang Yan , Hu Dongmei
Published: April 2021

Hollow porous fiber with both hollow and mesoporous structural characteristics can play an important role in storage, adsorption, and other fields. Triangular hollow porous fiber was prepared by coaxial wet spinning in this paper. Polyacrylonitrile (PAN) and N‐N dimethylformamide (DMF) were blended to get cortical solution. Polyvinylpyrrolidone (PVP) and DMF were blended to get core solution. Subsequently, coaxial triangular spinneret was adopted to inject solution into coagulation bath for double diffusion and obtain primary fiber. Then PAN‐based triangular fiber with high porosity was prepared after washing and drying. Scanning electron microscopy, nitrogen physical adsorption instrument, thermogravimetric analyzer, and other instruments were used to test and characterize. The results show that the cross‐section of the fiber is triangular and has a sense of luster. The hollow degree of the fiber is as high as 84.17%, and the sheath has three‐level structure with multi‐scale pore diameters, including micropores (200 μm), submicron pores (200 nm), and nanopores (20 nm). Through the range analysis of orthogonal experiment, it is found that the concentration of cortical solution is the main factor affecting the fiber tensile strength. When the concentration of cortical solution is 17%, the concentration of core solution is 10%, the flow rate ratio of cortical solution to core solution is 10:1, and the concentration of coagulation bath is 10%, the fiber tensile strength reaches 1.43 N/mm2. The thermal insulation performance of fiber is better than that of silk, cotton and polyester. The results in this paper will provide an experimental foundation for the design and application of hollow porous profiled fibers.
Human organ phantoms for catheterization using the radiation crosslinking technique
Authors: Imanishi Ayaka , Kimura Atsushi , Miyamoto Hisao , Hiroki Akihiro , Nagasawa Naotsugu , Yoshii Fumio , Taguchi Mitsumasa
Published: April 2021

An artificial organ based on polyvinyl alcohol (PVA) hydrogel was developed to train medical staff to improve their ablation therapy skills, by using the radiation cross‐linking technique. The aqueous PVA solution was irradiated with γ‐rays or electron beams to produce a highly transparent, high‐strength, and flexible crosslinked hydrogel without using a crosslinking agent. Physical properties of the hydrogel, such as, gel fraction, swelling, and elastic modulus, were controlled by changing the radiation dose. The catheter ablation region on the surface of the cardiac phantom produced from PVA hydrogel with temperature‐responsive pigment inks can be visually identified by the color change. The tumor organ phantom consists of the PVA hydrogel with the purple pigment ink (healthy organ site) and red PVA hydrogel with cellulose (the tumor sites) was developed by applying this radiation crosslinking technique. The positions of the tumor hydrogel and the ablation electrode needle can be confirmed through ultrasound echography. It is possible to practice ablation on the tumor site while observing the echo images under conditions similar to the actual treatment. These novel human organ phantoms are created as a means for ablation training for treating cardiac arrhythmia and liver cancer using the radiation crosslinking technology.
Zika virus outbreak in Brazil—Lessons learned and perspectives for a safe and effective vaccine
Authors: Sáfadi Marco Aurélio Palazzi , Almeida Flavia J. , de Ávila Kfouri Renato
Published: April 2021

Zika virus (ZIKV) is an emerging pathogen of public health concern, associated with a dramatic burden in places where the virus caused outbreaks between 2015 and 2017. In the Americas, the ZIKV was first reported in Brazil and rapidly spread through the Americas. Since its first report, a number of studies have been published as we continue to learn, not only about modes of transmission, but also clinical manifestations, risk of congenital anomalies, including microcephaly and neurological malformations in fetuses born from mothers infected during pregnancy. Interventions to reduce the burden of ZIKV infection are restricted to mosquito control, and for Aedes spp mosquitoes the strategies implemented to that end proved to be unsuccessful so far. Hence the lessons we can learn following the ZIKV epidemics become of paramount importance in the development of drug treatments and in search for a vaccine.
Temperaturinduktion in Betontragwerke
Authors: Clauß Felix , Löschmann Jens , Ahrens Mark Alexander , Mark Peter
Published: April 2021

Das Enteisen von Brückenfahrbahnen, die gesteuerte Erhärtung von Beton oder die Tragwerksverstärkung bei Temperierung sind Anwendungen für eine gezielte Temperaturinduktion in Betontragwerke. Der Beitrag behandelt dazu grundlegende Methoden. Dies sind das Erwärmen mit Infrarotstrahlern, Wärmematten oder erhitztem Wasser und das Kühlen mit Peltier‐Elementen, Kühlflüssigkeiten oder Trockeneis. Diskutiert werden die nominellen elektrischen Leistungen, die Fixierung am Bauteil, Interaktionen zwischen Temperierung und Bauteil, die Temperaturregelung und mögliche Verluste. Die Verfahren werden mit ihren Eigenschaften vorgestellt und bewertet. Als Basis dient eine Versuchsserie an Balken mit Einhausung durch Wärmedämmung. Die einzelnen Temperierverfahren werden separat untersucht und zur Erzeugung eines Temperaturgradienten kombiniert. Es zeigt sich, dass besonders Wärmematten oder Infrarotstrahler für das Heizen und die Peltier‐Kühlungen bzw. Kühlwasser für das Kühlen geeignet sind. Für die praktische Anwendung werden Empfehlungen abgeleitet.
Association of Brain‐Derived Neurotrophic Factor rs6265 G>A polymorphism and Post‐traumatic Stress Disorder susceptibility: A systematic review and meta‐analysis
Authors: Hu Xi‐Yi , Wu Yu‐Long , Cheng Chao‐Hui , Liu Xiao‐Xi , Zhou Lan
Published: April 2021

Background

Previous studies have shown that the brain‐derived neurotrophic factor (BDNF) rs6265 G > A polymorphism is closely related post‐traumatic stress disorder (PTSD) risk. However, the results were not consistent. We therefore conducted a meta‐analysis to explore the underlying relationships between BDNF rs6265 G > A polymorphism and PTSD risk.

Materials and Methods

Five online databases were searched, and all related studies were reviewed up to July 1, 2020. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to examine the statistical power of each genetic model. In addition, heterogeneity, sensitivity accumulative analysis, and publication bias were examined to check the statistical power.

Result

Overall, 16 publications involving 5,369 subjects were included in this systematic review and 11 case‐control studies were analyses in meta‐analysis. The pooled results indicated an increasing risk of A allele mutations with PTSD risk. Moreover, the sequential subgroup analysis also demonstrated some similar situations in Asian populations and other groups.

Conclusion

Current meta‐analysis suggests that the BDNF rs6265 G > A polymorphism might be involved in PTSD susceptibility.
Tuning J‐aggregate Formation and Emission Efficiency in Cationic Diazapentacenium Dyes
Authors: Rodrigues Ana Clara B. , Wetterling Dario , Scherf Ullrich , Seixas de Melo J. Sérgio
Published: April 2021

Enhancement of the luminescence efficiency of two new diazapentacenium salts (D1 and D2) of more than 55 for D1 and 22 times for D2) in poor solvents, acetonitrile and/or dichloromethane, was observed and rationalized as formation of emissive J‐aggregates. Both compounds displaying 4‐n‐decylphenyl substituents at the 7,14‐carbons and phenyl (D1) or 2,6‐difluorophenyl (D2) substituents at the quaternary nitrogen atoms in 5,12‐positions have been synthetized in a two‐step procedure involving a two‐fold Buchwald‐Hartwig‐type CN cross‐coupling and an electrophilic Friedel‐Crafts‐type cyclization. The optical properties of the dicationic diazapentacenium salts in various solvents and in thin films have been investigated by steady‐state and time‐resolved absorption and photoluminescence spectroscopies. In thin films and in good solvents, isolated molecules coexist with aggregates. Nonetheless, D1 is seven times more emissive than D2, reflecting a higher J‐aggregate contribution in the former.
Bis(Iminophosphorano)‐Substituted Pyridinium Ions and their Corresponding Bispyridinylidene Organic Electron Donors
Authors: Frenette Brandon L. , Arsenault Nadine , Walker Sarah L. , Decken Andreas , Dyker C. Adam
Published: April 2021

Optimized synthetic procedures for pyridinium ions featuring iminophosphorano (−N=PR3; R=Ph, Cy) π‐donor substituents in the 2‐ and 4‐ positions are described. Crystallographic and theoretical studies reveal that the strongly donating substituents severely polarize the π‐electrons of the pyridyl ring at the expense of aromaticity. Moreover, the pyridinium ions are readily deprotonated to generate powerful bispyridinylidene (BPY) organic electron donors. Electrochemical studies show exceptionally low redox potentials for the two‐electron BPY/BPY2+couples, ranging from −1.71 V vs the saturated calomel electrode for3PhPh(with four Ph3P=N− groups) to −1.85 V for3CyCy(with four Cy3P=N− groups). These new compounds represent the most reducing neutral organic electron donors (OEDs) currently known. Some preliminary reductions involving3CyCyshowed enhanced capability owing to its low redox potential, such as the thermally activated reduction of an aryl chloride, but purification challenges were often encountered.
Tuning the Nanoaggregates of Sialylated Biohybrid Photosensitizers for Intracellular Activation of the Photodynamic Response
Authors: Almeida‐Marrero Verónica , Mascaraque Marta , Jesús Vicente‐Arana María , Juarranz Ángeles , Torres Tomás , de la Escosura Andrés
Published: April 2021

In the endeavor of extending the clinical use of photodynamic therapy (PDT) for the treatment of superficial cancers and other neoplastic diseases, deeper knowledge and control of the subcellular processes that determine the response of photosensitizers (PS) are needed. Recent strategies in this direction involve the use of activatable and nanostructured PS. Here, both capacities have been tuned in two dendritic zinc(II) phthalocyanine (ZnPc) derivatives, either asymmetrically or symmetrically substituted with 3 and 12 copies of the carbohydrate sialic acid (SA), respectively. Interestingly, the amphiphilic ZnPc‐SA biohybrid (1) self‐assembles into well‐defined nanoaggregates in aqueous solution, facilitating cellular internalization and transport whereas the PS remains inactive. Within the cells, these nanostructured hybrids localize in the lysosomes, as usually happens for anionic and hydrophilic aggregated PS. Yet, in contrast to most of them (e. g., compound2), hybrid1recovers the capacity for photoinduced ROS generation within the target organelles due to its amphiphilic character; this allows disruption of aggregation when the compound is inserted into the lysosomal membrane, with the concomitant highly efficient PDT response.
A factorization‐based algorithm to predict EMG data using only kinematics information
Authors: Manzano Marta , Serrancolí Gil
Published: April 2021

EMG analyses have several applications, such as identifying muscle excitation patterns during rehabilitation or training plans, or controlling EMG‐driven devices. However, experimental measurements can be time consuming or difficult to obtain. This study presents a simple algorithm to predict EMG signals that can be applied in real time during running, given only the instantaneous vector of kinematics. We hypothesize that the factorization of the kinematics of the skeleton together with the EMG data of calibration subjects could be used to predict EMG data of another subject only using the kinematic information. The results showed that EMG signals of lower‐limb muscles can be predicted accurately in less than a second using this method. Correlation coefficients between predicted and experimental EMG signals were higher than 0.7 in 10 out of 11 muscles for most prediction trials and subjects, and their overall median value was higher than 0.8. These values confirm that this method could be used to accurately predict EMG signals in real time when only kinematics are measured.
Generation of Murine Bone Marrow and Fetal Liver Chimeras
Authors: Chappaz Stéphane , Saunders Tahnee L. , Kile Benjamin T.
Published: April 2021

The generation of radiation chimeras allows researchers to substitute the hematopoietic system of a mouse with that of one or more donors. A suspension of hematopoietic stem cells (HSCs) is prepared from the bone marrow (BM) or the fetal liver (FL) of a donor mouse and adoptively transferred into an irradiated recipient. Within days, the donor's HSCs will engraft, and their progeny will quickly replace the blood cells of the recipient. This simple tool, together with the large availability of genetically modified mouse lines, can be harnessed to manipulate and study various aspects of blood cell biology in vivo. We present here protocols to generate three types of radiation chimera: (1) BM chimeras, which can assist in determining whether the origin of a genetically based phenotype is the hematopoietic or radio‐resistant compartment and which are also conducive for studying the ecology of blood cells and for manipulating the environment hematopoietic cells live; (2) FL chimeras, which allow the study of hematopoietic systems from animals that carry genetic modifications incompatible with postnatal life; and (3) mixed BM chimeras, in which the hematopoietic system comprises blood cells of two different genotypes. Mixed BM chimeras can be used to identify genes that affect hematopoietic cell fitness and to establish whether secreted factors mediate a phenotype of interest. © 2021 Wiley Periodicals LLC.

Basic Protocol 1: Generation of bone marrow chimera

Basic Protocol 2: Generation of fetal liver chimera

Basic Protocol 3: Generation of mixed bone marrow chimera

Support Protocol 1: Isolation of bone marrow cells

Support Protocol 2: Cell counting by flow cytometry

Support Protocol 3: Assessment of chimerism
Seed‐rain–successional feedbacks in wet tropical forests
Authors: Huanca Nuñez Nohemi , Chazdon Robin L. , Russo Sabrina E.
Published: April 2021

Tropical forest regeneration after abandonment of former agricultural land depends critically on the input of tree seeds, yet seed dispersal is increasingly disrupted in contemporary human‐modified landscapes. Here, we introduce the concept of seed‐rain–successional feedbacks as a deterministic process in which seed rain is shaped by successional dynamics internal to a forest site and that acts to reinforce priority effects. We used a combination of time series and chronosequence approaches to investigate how the quantity and taxonomic and functional composition of seed rain change during succession and to evaluate the strength of seed‐rain–successional feedbacks, relative to other deterministic and stochastic mechanisms, in secondary wet forests of Costa Rica. We found that both successional niches and seed‐rain–successional feedbacks shaped successional trajectories in the seed rain. Determinism due to successional niche assembly was supported by the increasing convergence of community structure to that of a mature forest, in terms of both functional and taxonomic composition. With successional age, the proportions of large‐seeded, shade‐tolerant species in the seed rain increased, whereas the proportion of animal‐dispersed species did not change significantly. Seed‐rain–successional feedbacks increased in strength with successional age, as the proportion of immigrant seeds (species not locally represented in the site) decreased with successional age, and the composition of the seed rain became more similar to that of the adult trees at the forest site. The deterministic assembly generated by seed‐rain–successional feedback likely contributed to the increasing divergence of secondary forest sites from each other during succession. To the extent that human modification of tropical forest landscapes reduces connectivity via factors such as forest cover loss, our results suggest that seed‐rain–successional feedbacks are likely to increasingly shape regeneration trajectories in and amplify floristic heterogeneity among tropical secondary forests.
Characterization of O+ Ion‐implanted Glassy Carbon Using the Superconducting Electron Cyclotron Resonance Ion Source and Selective Dopamine Detection
Authors: Park Jin Yong , Lee Dong‐Wook , Hong Jonggi , Kim Seong Jun , Ok Jung‐Woo , Yoon Jang‐Hee , Won Mi‐Sook
Published: April 2021

The O and N gas ions (O3+, O+, N2+, and N4+) were implanted on the glassy carbon surface employing the electron cyclotron resonance ion source, which were characterized using electrochemical and surface analysis methods. The modified electrode was examined for the catalytic oxidation of bioorganic molecules including dopamine, where the O+ ion implanted GC revealed the best catalytic performance. The XPS and Raman results represented that the ion implantation made enrichment in graphite nanocrystalline structure with edge plane, showing the enhanced electrochemical activity. It showed excellent performance for dopamine detection without significant interferences between 50.0 nM and 400.0 μM with the detection limit of 10.0±2.5 nM (95 % confidence level). The reliability of proposed electrode was evaluated by the real urine sample analysis.
Device uncertainty propagation in low‐ductility RC frames retrofitted with BRBs for seismic risk mitigation
Authors: Freddi Fabio , Ghosh Jayadipta , Kotoky Needhi , Raghunandan Meera
Published: April 2021

Passive control systems, such as buckling‐restrained braces (BRBs), have emerged as efficient tools for seismic response control of new and existing structures by imparting strength and stiffness to buildings, while providing additional high and stable energy dissipation capacity. Systems equipped with BRBs have been widely investigated in literature; however, only a deterministic description of the BRBs’ properties is typically considered. These properties are provided by the manufacturer and are successively validated by qualification control tests according to code‐based tolerance limits. Therefore, the device properties introduced within the structure could differ from their nominal design estimates, potentially leading to an undesired seismic performance. This study proposes a probabilistic assessment framework to evaluate the influence of BRBs’ uncertainty on the seismic response of a retrofitted RC frame. For the case study, a benchmark three‐story RC moment‐resisting frame is considered where BRBs’ uncertainty is defined compatible to the standardized tolerance limits of devices’ quality control tests. This uncertainty is implemented through a two‐level factorial design strategy and Latin hypercube sampling technique. Cloud analysis and probabilistic seismic demand models are used to develop fragility functions for the bare and retrofitted frame for four damage states while also accounting for the uncertainty in the property of BRBs. Risk estimates are successively evaluated for three case study regions. The results show that, for the considered case study structure, these uncertainties could lead to an increase of fragility up to 21% and a variation in seismic risk estimates up to 56%.
Computational aeroacoustic modeling using hybrid Reynolds averaged Navier–Stokes/large‐eddy simulations methods with modified acoustic analogies
Authors: Nyandeni Zamashobane , Chinyoka Tiri
Published: April 2021

This study employs a numerical approach to investigate noise mechanisms in tandem cylinders. The tandem cylinder configuration is an excellent model for aircraft landing gear. The study is therefore primarily motivated by the need to understand the aircraft landing gear as a primary contributor to airframe noise during approach and landing. Fluctuations in the flow properties induced by turbulent flow around the tandem cylinders are computed and analyzed. A hybrid improved delayed detached eddy simulation turbulence model is employed to compute the boundary layer flow as well as to compute the fluctuations in the flow properties. The numerical methodologies for the turbulent flow computations are implemented on the OpenFOAM software platform. The study also considers the impact of neglecting the volume sources and employs two modified versions of Curle's and Ffowcs‐Williams and Hawkings analogies. The results are in good agreement with published numerical and experimental data in the existing literature.
Beschreibung von Fels als Baugrund für Talsperren und Wasserkraftanlagen – Erfahrungen aus Sicht des Feldgeologen
Authors: Dietler Thomas
Published: April 2021

The characterisation of rock as a foundation for hydropower plants in general and dams in particular is highly complex and requires a great deal of experience on the part of the geologists involved. Geology cannot be studied remotely; it requires geological field surveys and investigations. This paper describes the aspects to be considered, the planning of the investigations and the degree of detail needed at the various planning phases from the field geologist's perspective. It also highlights the internationally recognised methods of investigation used for large‐scale projects and describes how the results are documented and recorded. It concludes by briefly outlining the soft factors which constitute an integral part of successful geological feasibility studies. Geology is an ”inexact“ science that requires extensive experience in order to generate the most realistic ground model possible. For this reason, a clear distinction must be made between facts (basic data) and their interpretation (experience). Furthermore, it is important to consider what other conclusions can be drawn from surveying the subsoil.
Erweiterung Kraftwerk Kirchbichl in Tirol – Herausforderungen an den Spezialtiefbau
Authors: Hautz Werner , Neuner Johann
Published: April 2021

Tiwag – Tiroler Wasserkraft AG sees itself as a driving force in the energy transition, pursuing the goals of the Tyrolean and Austrian energy strategies with a moderate, environment friendly expansion of hydropower. The projects are essentially aimed at expanding existing power plants so that they can be used more effectively, and additional hydropower potential can be developed. The Kirchbichl Power Plant is a good case in point. From 2017 to 2020, the power plant was made fit for the next decades as part of an extensive refurbishment and expansion project. The main project components are to improve flood security through the construction of an additional weir field, to adapt to enhanced environmental standards through the construction of a fish passage and a power plant for residual flow, and to increase the discharge of the power plant by installing an additional turbine. One of the challenges was the construction pits in the immediate vicinity of the existing system. The pit design with bored pile retaining wall and base seal with a jet grout slab has proven to be very effective.
Investigating oligodendrocyte connexins: Heteromeric interactions between Cx32 and mutant or wild‐type forms of Cx47 do not contribute to or modulate gap junction function
Authors: Abrams Charles K. , Flores‐Obando Rafael E. , Dungan Gabriel D. , Cherepanova Elina , Freidin Mona M.
Published: April 2021

Oligodendrocytes express two gap junction forming connexins, connexin 32 (Cx32) and Cx47; therefore, formation of heteromeric channels containing both Cx47 and Cx32 monomers might occur. Mutations in Cx47 cause both Pelizaeus–Merzbacher‐like disease Type 1 (PMLD1) and hereditary spastic paraparesis Type 44 (SPG44) and heteromer formation between these mutants and Cx32 may contribute to the pathogenesis of these disorders. Here, we utilized electrophysiological and antibody‐based techniques to examine this possibility. When cells expressing both Cx32 and Cx47 were paired with cells expressing either Cx32 or Cx47, properties were indistinguishable from those produced by cells expressing homotypic Cx32 or Cx47 channels. Similarly, pairing cells expressing both Cx32 and Cx47 with cells expressing Cx30 or Cx43 produced channels indistinguishable from heterotypic Cx32/Cx30 or Cx47/Cx43 channels, respectively. The same assessments were performed on cells expressing Cx32 and four mutant forms of Cx47 (p.I33M associated with SPG44 or p.P87S, p.Y269D or p.M283T associated with PMLD1). None of these mutants showed a functional effect on Cx32. Immunostained cells co‐expressing Cx32WT (wild type) and Cx47WT showed a Pearson correlation coefficient close to zero, suggesting that any overlap was due to chance. p.Y269D showed a statistically significant negative correlation with Cx32, suggesting that Cx32 and this mutant overlap less than expected by chance. Co‐immunoprecipitation of Cx32 with Cx47WT and mutants show only very low levels of co‐immunoprecipitated protein. Overall, our data suggest that interactions between PMLD1 or SPG44 mutants and Cx32 gap junctions do not contribute to the pathogenesis of these disorders.
Taking the body off the mind: Decreased functional connectivity between somatomotor and default‐mode networks following Floatation‐REST
Authors: Al Zoubi Obada , Misaki Masaya , Bodurka Jerzy , Kuplicki Rayus , Wohlrab Colleen , Schoenhals William A. , Refai Hazem H. , Khalsa Sahib S. , Stein Murray B. , Paulus Martin P. , Feinstein Justin S.
Published: April 2021

Floatation‐Reduced Environmental Stimulation Therapy (REST) is a procedure that reduces stimulation of the human nervous system by minimizing sensory signals from visual, auditory, olfactory, gustatory, thermal, tactile, vestibular, gravitational, and proprioceptive channels, in addition to minimizing musculoskeletal movement and speech. Initial research has found that Floatation‐REST can elicit short‐term reductions in anxiety, depression, and pain, yet little is known about the brain networks impacted by the intervention. This study represents the first functional neuroimaging investigation of Floatation‐REST, and we utilized a data‐driven exploratory analysis to determine whether the intervention leads to altered patterns of resting‐state functional connectivity (rsFC). Healthy participants underwent functional magnetic resonance imaging (fMRI) before and after 90 min of Floatation‐REST or a control condition that entailed resting supine in a zero‐gravity chair for an equivalent amount of time. Multivariate Distance Matrix Regression (MDMR), a statistically‐stringent whole‐brain searchlight approach, guided subsequent seed‐based connectivity analyses of the resting‐state fMRI data. MDMR identified peak clusters of rsFC change between the pre‐ and post‐float fMRI, revealing significant decreases in rsFC both within and between posterior hubs of the default‐mode network (DMN) and a large swath of cortical tissue encompassing the primary and secondary somatomotor cortices extending into the posterior insula. The control condition, an active form of REST, showed a similar pattern of reduced rsFC. Thus, reduced stimulation of the nervous system appears to be reflected by reduced rsFC within the brain networks most responsible for creating and mapping our sense of self.
MicroRNA‐mediated extracellular matrix remodeling in squamous cell carcinoma of the oral cavity
Authors: Menderico Junior Gilberto Mendes , Theodoro Thérèse Rachell , Pasini Fatima Solange , de Menezes Ishikawa Marina , Santos Nayara Stephânie Sousa , de Mello Evandro Sobroza , da Silva Pinhal Maria Aparecida , Moyses Raquel Ajub , Kulcsar Marco Aurelio Vamondes , Dedivitis Rogério Aparecido , Cernea Claudio Roberto , Kowalski Luiz Paulo , de Matos Leandro Luongo
Published: April 2021

Background

We evaluated microRNAs and extracellular matrix component profiles in squamous cell carcinoma of the oral cavity (OSCC) in comparison to healthy mucosa.

Methods

Retrospective study investigating 64 microRNAs related to oncogenic process and to constituents of the extracellular matrix. We also performed immunohistochemical assays for molecules involved in the same biological processes.

Results

High expression of miR‐21‐5p (p < 0.001) and miR‐106‐5p (p < 0.001) and low expression of miR‐320a (p= 0.001) and miR‐222‐3p (p= 0.001) were predictors of malignancy. Individually, miR‐21‐5p exhibited the best statistical performance (area under the curve = 0.972; 95% confidence interval: 0.911–1.000) in the differentiation between tumor tissue and healthy mucosa. Moreover, tumor sample showed increased expression of MMP‐2, MMP‐9, α‐laminin, and β‐laminin in tumor‐related fibroblasts and lower continuity of type IV collagen in the basement membrane.

Conclusion

The present study demonstrates the biological effects of microRNAs on the carcinogenesis of OSCC as well as the intense modification of the tumor microenvironment.
Evaluating lacustrine groundwater discharge to a large glacial lake using regional scale radon‐222 surveys and groundwater modelling
Authors: Wallace Hayley , Wexler E. J. , Malott Spencer , Robinson Clare E.
Published: April 2021

Lacustrine groundwater discharge (LGD) can be an important pathway for delivering pollutants to lakes but this pathway is often poorly characterized. Evaluating the potential impact of LGD on lake water quality requires understanding the magnitude and spatial variability of LGD, as well as understanding the age and flow paths of the discharging groundwater (e.g., recharge area, groundwater flow paths, and travel times). This study first compares LGD rates along two ~40 km shoreline lengths of a large glacial lake, Lake Simcoe, Canada, that were independently estimated via a radon‐222 (222Rn) field survey and via regional scale groundwater‐surface water modelling. Backward particle tracking analysis is then used to examine the age and flow paths of the LGD and thereby assess the potential for the LGD to deliver anthropogenic pollutants to the lake. The field and modelling results compare well with respect to the magnitude and spatial variability of LGD. However, the comparison highlights the need for well‐defined hydrogeological characterization if regional scale models are to be applied for LGD estimation. The particle tracking analysis indicates large variation in the groundwater flow path lengths and travels times (>1000 years to <50 years) for LGD along the shoreline. This illustrates that the LGD along different shoreline areas has varying potential to deliver anthropogenic pollutants to the lake. The study findings demonstrate the benefits of comparing independent field measured and model‐simulated LGD estimates, and moreover suggest that it may be possible, in some cases, to use existing regional scale groundwater‐surface water models, purpose‐built for other water resource and quality objectives, to conduct preliminary evaluation of LGD contributions to lakes. Preliminary model‐based evaluation would enable field efforts aiming to quantify and manage LGD to be better targeted rather than relying solely on regional scale field techniques that are often highly resource intensive.
Origin of sulphate in the unsaturated zone and groundwater of a loess aquifer
Authors: Long Yin , Huang Tianming , Zhang Fen , Li Zhenbin , Ma Baoqiang , Li Yiman , Pang Zhonghe
Published: April 2021

The use of the sulphate mass balance (SMB) between precipitation and soil water as a supplementary method to estimate the diffuse recharge rate assumes that the sulphate in soil water originated entirely from atmospheric deposition; however, the origin of sulphate in soil and groundwater is often unclear, especially in loess aquifers. This study analysed the sulphur (δ34S‐SO4) and oxygen (δ18O‐SO4) isotopes of sulphate in precipitation, water‐extractable soil water, and shallow groundwater samples and used these data along with hydrochemical data to determine the sources of sulphate in the thick unsaturated zone and groundwater of a loess aquifer. The results suggest that sulphate in groundwater mainly originated from old precipitation. When precipitation percolates through the unsaturated zone to recharge groundwater, sulphates were rarely dissolved due to the formation of CaCO3 film on the surface of sulphate minerals. The water‐extractable sulphate in the deep unsaturated zone (>10 m) was mainly derived from the dissolution of evaporite minerals and there was no oxidation of sulphide minerals during the extraction of soil water by elutriating soil samples with deionized water. The water‐extractable concentration of SO4 was not representative of the actual SO4 concentration in mobile soil water. Therefore, the recharge rate cannot be estimated by the SMB method using the water‐extractable concentration of SO4 in the loess areas. This study is important for identifying sulphate sources and clarifying the proper method for estimating the recharge rate in loess aquifers.
Considering the 3Rs for castration and tail docking in sheep
Authors: Gascoigne Emily , Mouland Charlotte , Lovatt Fiona
Published: April 2021

Background: Tail docking and castration in lambs are permitted in the UK and are governed by multiple legislations including the Protection of Animals (Anaesthetics) Act (1954), the Veterinary Surgeons Act (1966), the Welfare of Livestock Regulations (1982), the Animal Welfare Act (2006) and the Mutilations (Permitted Procedures)(England) Regulations (2007). However, with political uncertainty and increasing consumer interest in how red meat is produced, the changing global agenda with reference to mutilations will mean that such procedures in the UK are increasingly under the spotlight and may require increasing justification on farm. Notably, the pain caused by these mutilations and their blanket use in regards to sheep production feature on the agenda of several animal welfare charities, including Compassion in World Farming and People for Ethical Treatment of Animals.

Aim of the article: With over 10 years since the publication of the Farm Animal Welfare Council's (FAWC) report discussing the implications of these mutilation procedures on the welfare of lambs (FAWC 2008), and the recent publication of the BVA's policy on tail docking and castration (BVA 2020), in this article we will review the debate. Key areas that are considered include the changes in perception of mutilations; the developments in the evidence since the FAWC's publication; the current legislation and how global practices adhere to these rules; the European perspective of mutilations; and how the ‘reduce, refine, replace’ (3Rs) approach can be applied to mutilation discussions when preparing health plans. The arguments surrounding this topic are complex and the ultimate driver for any discussion on farm should be maximising overall animal welfare.
Using efficiency models to redefine veterinary practice following Covid‐19
Authors: Manktelow Paul
Published: April 2021

The Covid‐19 pandemic created the most urgent platform for change that the veterinary profession has ever seen. Every business in every sector throughout the world was forced to simultaneously redesign itself from the ground up against a singular overriding imperative – social distancing. As human safety became the priority, established systems, processes and operating models were torn apart and hastily replaced. This article illustrates how using efficiency models can help practices recover and redefine their working models following the pandemic.
In a Minsky Moment, can financial statement data predict stock market crashes and recessions?
Authors: Bressler Paige D.
Published: April 2021

The Financial Instability Hypothesis posits that debt, and the validation of debt characterizes the state of the economy. A Minsky Moment is a swift collapse of asset prices after a long period of debt‐fueled growth. Current literature lacks empirical analysis to validate the Financial Instability Hypothesis with respect to stock market crashes and financial crises. Based on Vercelli’s (2009) interpretation, Minskys’ characterization of debt validation is based on two indices. This first index depicts the current liquidity of a firm. The second index depicts the expected solvency of a firm. Both the liquidity index and the solvency index can be calulated using financial statement data. Using Compustat data from 1982 to 2015 in a probit regression model, this paper supports how the role of debt and how the change in the validation of debt predict a stock market crash and an onset of a recession. This study contributes to the existing literature by being the first study to support the validity of the Financial Instability Hypothesis using financial statement data and by creating a model to predict future stock crashes and recessions.
Robotic‐assisted laparoscopic tumor enucleation is a feasible technique for renal hilar tumors: A retrospective study
Authors: Liu Tianyao , Zhao Zihan , Feng Baofu , Wang Xin , Li Tianhang , Xie Shangxun , Zhu Wenjie , Li Xiaogong , Guo Hongqian , Yang Rong
Published: April 2021

Background and Objective

This study aimed to evaluate the safety and efficacy of robot‐assisted laparoscopic tumor enucleation (RAE) for the treatment of renal hilar tumors and to describe our experience with renorrhaphy‐related surgical techniques.

Methods

Retrospective data were collected from 173 consecutive patients who underwent RAE for localized renal tumors (cT1–cT2N0M0) at our hospital between September 2014 and November 2019.

Results

Seventy‐five patients had renal hilar tumors and 98 patients had nonhilar tumors. There were no statistical differences between the hilar and nonhilar groups in operation time (190 [115–390] vs. 190 [110–390] min, p = 0.889), warm ischemia time (26 [12–60] vs. 27 [17–41] min, p = 0.257), hospital stay duration (8 [3–16] vs. 7.5 [4–18] days, p = 0.386), renal function (estimated glomerular filtration rate, 102.5 [29.4–144] vs. 101.3 [64.2–134.7] ml/min/1.73 m2, p = 0.631); creatinine level, (76 [43–169] vs. 78.5 [50–281.3] µmol/L, p = 0.673), perioperative complications rate, or surgical margin status. However, patients with hilar tumors lost significantly more blood than did those with nonhilar tumors (250 [50–1500] vs. 200 [20–1200] ml, p = 0.007). During the follow‐up period (median, 30 months), three patients in each group experienced recurrence. The 5‐year recurrence‐free rates were 93.0% and 95.4% in the hilar and nonhilar tumor groups, respectively (p = 0.640).

Conclusions

For experienced robot laparoscopists, RAE is a safe, effective, and feasible procedure for renal hilar tumors, without increased risk of positive surgical margins or worse midterm oncologic outcomes compared with nonhilar tumors.
Liquid chromatography–tandem mass spectrometry measurement of 26 steroid hormones in human serum and plasma samples
Authors: Jia Yongjuan , Liu Xingli , Xu Li , Zhao Jinbao , Ni Junjun , Zhang Yuanyuan
Published: April 2021

The measurement of steroid hormones provided critical information in the clinical evaluation of endocrine disorders. In this study, we developed a high‐throughput solid‐phase extraction method for the analysis of 26 steroids in human serum and plasma samples by liquid chromatography–tandem mass spectrometry. Chromatographic conditions and sample preparation were optimized to achieve good separation and maximum sensitivity for these analytes. Under the optimum conditions, good linearities were achieved in the quantitative range for each steroid hormone with the correlation coefficients (r) larger than 0.99. The limits of quantitation of the method were in the range from 0.0005 to 0.7901 ng/mL. The recoveries were in the range of 87.2–114.2% with intra‐ and interday precision lower than 9.94%. This method has already been applied to series of samples from clinical trials, and there was no significant difference between serum and ethylenediaminetetraacetic acid plasma samples.
Patterns of Recurrence of Phonotraumatic Vocal Fold Lesions Suggest Distinct Mechanisms of Injury
Authors: Lee Mark , Mau Ted , Sulica Lucian
Published: April 2021

Objectives/Hypothesis

To examine patterns of recurrence of benign phonotraumatic vocal fold lesions over time for insights into pathophysiology.

Study Design

Case series with mathematical modeling.

Methods

Medical records and stroboscopic exams of adults who underwent microlaryngoscopic resection of phonotraumatic vocal fold lesions over a 13‐year period were reviewed for time to recurrence after surgery. Uniform and log‐normal probability distributions were fitted to the time to recurrence curves for vocal fold polyps, midfold masses, and pseudocysts. Model fits were compared using the Akaike information criterion corrected, a standard measure of the goodness of fit. Stochastic simulations were used to verify that the mechanistic hypotheses were concordant with the selected probability distributions and empiric data.

Results

Of 567 patients who underwent microlaryngoscopic resection, 65 had a recurrence (16 polyps, 14 midfold masses, and 35 pseudocysts). Midfold mass and pseudocyst recurrences were predominantly seen in younger women. Polyps were best fit by a uniform distribution rather than log‐normal, whereas midfold masses and pseudocysts were better fit by log‐normal rather than uniform. Stochastic simulations suggest that polyps recur sporadically according to a paroxysmal‐developmental model, whereas midfold mass and pseudocyst recurrences follow a force‐multiplication, damage‐accumulation process.

Conclusions

Vocal fold polyps are acute lesions evenly distributed by age and gender that recur uniformly over time, suggesting they arise from sudden tissue reactions to phonotraumatic stress. Pseudocysts and midfold fibrous masses are chronic lesions predominantly found in young women that recur with log‐normal distribution over time, suggesting gradual damage accumulation in larynges predisposed to enhanced phonotrauma.

Level of Evidence

4 Laryngoscope, 131:2523–2529, 2021
A collaborative learning health system agent‐based model: Computational and face validity
Authors: Seid Michael , Bridgeland David , Bridgeland Alexandra , Hartley David M.
Published: April 2021

Introduction

Improving the healthcare system is a major public health challenge. Collaborative learning health systems (CLHS) ‐ network organizations that allow all healthcare stakeholders to collaborate at scale ‐ are a promising response. However, we know little about CLHS mechanisms of actions, nor how to optimize CLHS performance. Agent‐based models (ABM) have been used to study a variety of complex systems. We translate the conceptual underpinnings of a CLHS to a computational model and demonstrate initial computational and face validity.

Methods

CLHSs are organized to allow stakeholders (patients and families, clinicians, researchers) to collaborate, at scale, in the production and distribution of information, knowledge, and know‐how for improvement. We build up a CLHS ABM from a population of patient‐ and doctor‐agents, assign them characteristics, and set them into interaction, resulting in engagement, information, and knowledge to facilitate optimal treatment selection. To assess computational and face validity, we vary a single parameter ‐ the degree to which patients influence other patients ‐ and trace its effects on patient engagement, shared knowledge, and outcomes.

Results

The CLHS ABM, developed in Python and using the open‐source modeling framework Mesa, is delivered as a web application. The model is simulated on a cloud server and the user interface is a web browser using Python and Plotly Dash. Holding all other parameters steady, when patient influence increases, the overall patient population activation increases, leading to an increase in shared knowledge, and higher median patient outcomes.

Conclusions

We present the first theoretically‐derived computational model of CLHSs, demonstrating initial computational and face validity. These preliminary results suggest that modeling CLHSs using an ABM is feasible and potentially valid. A well‐developed and validated computational model of the health system may have profound effects on understanding mechanisms of action, potential intervention targets, and ultimately translation to improved outcomes.
Reduction of Visceral Adiposity as a Predictor for Resolution of Nonalcoholic Fatty Liver in Potential Living Liver Donors
Authors: Lee Sunyoung , Kim Kyoung Won , Lee Jeongjin , Park Taeyong , Park Hyo Jung , Song Gi‐Won , Lee Sung‐Gyu
Published: April 2021

This study aimed to determine the factors associated with resolution of nonalcoholic fatty liver (NAFL) after lifestyle intervention in potential living liver donors as assessed by the gold standards in a longitudinal setting. This retrospective study included 115 potential living liver donors (mean age, 30.5 ± 7.5 years; 101 men) with NAFL who underwent paired liver biopsies and abdominal computed tomography (CT) examinations before and after lifestyle intervention between January 2011 and December 2018. Anthropometry, laboratory parameters, body composition, and hepatic steatosis (HS) were evaluated before and after lifestyle intervention. Anthropometry, laboratory parameters, body composition, and HS were significantly decreased after lifestyle intervention (all, P < 0.001). Relative changes in HS were weakly correlated with relative changes in the visceral fat area (VFA; r = 0.278; P = 0.003) and subcutaneous fat area (r = 0.382; P < 0.001), but not with body weight, body mass index, or skeletal muscle area. Patients with resolved NAFL after lifestyle intervention had significantly lower VFA at follow‐up than those with persistent NAFL (mean ± standard deviation, 69.8 ± 39.1 versus 91.5 ± 41.4 cm2; P = 0.01). Multivariable logistic regression analysis demonstrated that the relative reduction of VFA (odds ratio per percent, 1.031; 95% confidence interval, 1.010‐1.053; P = 0.004) was a significant independent factor associated with resolved NAFL after lifestyle intervention. In potential living liver donors with NAFL, the reduction of VFA is a significant factor associated with the resolution of NAFL after lifestyle intervention.
An Intrinsically‐Adhesive Family of Injectable and Photo‐Curable Hydrogels with Functional Physicochemical Performance for Regenerative Medicine
Authors: Karami Peyman , Nasrollahzadeh Naser , Wyss Céline , O'Sullivan Aine , Broome Martin , Procter Philip , Bourban Pierre‐Etienne , Moser Christophe , Pioletti Dominique P.
Published: April 2021

Attaching hydrogels to soft internal tissues is crucial for the development of various biomedical devices. Tough sticky hydrogel patches present high adhesion, yet with lack of injectability and the need for treatment of contacting surface. On the contrary, injectable and photo‐curable hydrogels are highly attractive owing to their ease of use, flexibility of filling any shape, and their minimally invasive character, compared to their conventional preformed counterparts. Despite recent advances in material developments, a hydrogel that exhibits both proper injectability and sufficient intrinsic adhesion is yet to be demonstrated. Herein, a paradigm shift is proposed toward the design of intrinsically adhesive networks for injectable and photo‐curable hydrogels. The bioinspired design strategy not only provides strong adhesive contact, but also results in a wide window of physicochemical properties. The adhesive networks are based on a family of polymeric backbones where chains are modified to be intrinsically adhesive to host tissue and simultaneously form a hydrogel network via a hybrid cross‐linking mechanism. With this strategy, adhesion is achieved through a controlled synergy between the interfacial chemistry and bulk mechanical properties. The functionalities of the bioadhesives are demonstrated for various applications, such as tissue adhesives, surgical sealants, or injectable scaffolds.