bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence of Phonon‐Mediated Superconductivity in LaH10 at High Pressure
Authors: Durajski Artur P. , Wang Chongze , Li Yinwei , Szczȩśniak Radosław , Cho Jun‐Hyung
Published: December 2020

Motivated by the recent experimental discovery of the high‐critical‐temperature superconductor LaH10 (250–260 K at high pressures 170–190 GPa), the influence of H isotope substitution on the phonon spectra, electron–phonon interactions, and thermodynamic properties of superconducting LaHDx () at 250 GPa are studied. On the basis of first‐principles calculations, it is found that all investigated systems are dynamically stable in a clathrate structure with space group Fmm and exhibit high superconducting critical temperatures ranging from 169 to 234 K. The dominant role of hydrogen in enhancing is examined by numerically solving the Eliashberg equations. The estimated critical temperature, superconducting energy gap, specific heat, and thermodynamic critical field demonstrate that the underlying mechanism of superconductivity in lanthanum hydride is conventional electron–phonon coupling, which manifests itself in terms of isotope effect.
'Plate‐like‐coral' polymer particles with dendritic structure and porous channels: Effective delivery of anti‐cancer drugs
Authors: Amgoth Chander , Dharmapuri Gangappa , Patra Sukanya , Wasnik Kirti , Gupta Premshankar , Kalle Arunasree M. , Paik Pradip
Published: December 2020

'Plate‐like‐coral'shaped polymer capsule (PC‐PLCDB) with dendritic network structure and porous channels has been synthesized and used for therapeutic purposes. First di‐block copolymer [(PEG)‐b‐(L‐AspA)n] has been synthesized from PEG (polyethylene glycol) and aspartic acid (AspA). Then the biocompatible PC‐PLCDB has been achieved by homogeneous mixing of [(PEG)‐b‐(L‐AspA)n] and poly‐N‐isopropyl acrylamide (PNIPAM) followed by reprecipitation. Only H‐bonding is responsible for the foundation of self‐assembly of the polymer chains and to form PC‐PLCDB. A huge extent of loading anticancer drug, for example, doxorubicin (DOX) in PC‐PLCDB is possible. in vitro study has been performed to check the therapeutic efficacy of PC‐PLCAD‐DOX formulation on chronic myeloid leukemia cells (K562). The IC50has been calculated to be 0.405 (±0.014) ng μg−1of the formulation. PC‐PLCAD‐DOX inhibits 80% of the cancer cell only by 1.0 μg mL−1of the formulation. This study reveals that the PC‐PLCAD could be a promising candidate for therapeutic applications.
Biodegradation evaluation of poly (lactic acid) for stent application: Role of mechanical tension and temperature
Authors: Khalaj Amnieh Sasan , Mosaddegh Peiman , Mashayekhi Mohammad , Kharaziha Mahshid
Published: December 2020

In this study, an experimental investigation is conducted on mechanical characteristics of poly(lactic acid) (PLA), before, and during degradation for stent application. A bioreactor is designed and fabricated to mimic in‐vivo environment of the body for studying degradation behavior of PLA fibers manufactured by melt spinning method. Beside PLA fibers, the degradation of PLA braided stents is investigated as control samples. To measure stress–strain and stress relaxation properties of PLA fibers, tensile, and relaxation tests are conducted. The decreasing trend of Young's modulus, variations in residual stress value after relaxation and pattern of stress relaxation are found during degradation. The influence of effective parameters, that is, temperature and stress, on PLA degradation is also studied. Moreover, the PLA degradation is analyzed by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA) and microscopic images. GPC results indicate the molecular weight decreases from 196,000 to 80,000 due to degradation while DSC analysis confirmed that the degradation promote an increase in PLA degree of crystallinity (from 43.3% to 59.8%). In addition, TGA results show that the PLA thermal stability decreases during degradation. This study provides useful information on PLA properties during degradation to assess the material in context of degradable stents.
Production and monitoring of biomass and fucoxanthin with brown microalgae under outdoor conditions
Authors: Gao Fengzheng , Sá Marta , Teles (Cabanelas, ITD) Iago , Wijffels René H. , Barbosa Maria J.
Published: December 2020

The effect of light on biomass and fucoxanthin (Fx) productivities was studied in two microalgae, Tisochrysis lutea and Phaeodactylum tricornutum. High and low biomass concentrations (1.1 and 0.4 g L−1) were tested in outdoor pilot‐scale flat‐panel photobioreactors at semi‐continuous cultivation mode. Fluorescence spectroscopy coupled with chemometric modeling was used to develop prediction models for Fx content and for biomass concentration to be applied for both microalgae species. Prediction models showed high R2 for cell concentration (.93) and Fx content (.77). Biomass productivity was lower for high biomass concentration than low biomass concentration, for both microalgae (1.1 g L−1: 75.66 and 98.14 mg L−1 d−1, for T. lutea and P. tricornutum, respectively; 0.4 g L−1: 129.9 and 158.47 mg L−1 d−1, T. lutea and P. tricornutum). The same trend was observed in Fx productivity (1.1 g L−1: 1.14 and 1.41 mg L−1 d−1, T. lutea and P. tricornutum; 0.4 g L−1: 2.09 and 1.73 mg L−1 d−1, T. lutea and P. tricornutum). These results show that biomass and Fx productivities can be set by controlling biomass concentration under outdoor conditions and can be predicted using fluorescence spectroscopy. This monitoring tool opens new possibilities for online process control and optimization.
Polydiacetylenes Functionalized with Chelidamic Acid and 2,2'‐Dipicolylamine for Colorimetric Responses to Cadmium Ions
Authors: Pham Thanh Chung , Kim Hyun Sung , Lee Songyi
Published: December 2020

A novel polydiacetylene‐linked ligand derived from the reaction between chelidamic acid and bis(pyridin‐2‐ylmethyl)amine (PDA‐CB) showed excellent selectivity and sensitivity for Cd2+ ions compared with other metal ions, including Zn2+. An obvious color change between PDA‐CB and PDA‐CB + Cd2+ is clearly visible to the naked eye. The Cd2+‐responsive color change of PDA‐CB is attributed to the coordination between Cd2+ and CB ligand units and has been characterized by 1H NMR titration.
Surveillance for radiation‐related late effects in childhood cancer survivors: The impact of using volumetric dosimetry
Authors: Cohen‐Cutler Sally , Olch Arthur , Wong Kenneth , Malvar Jemily , Sposto Richard , Kobierski Pierre , Sura Amit , Constine Louis S. , Freyer David R.
Published: December 2020

Background

Radiation‐related screening guidelines for survivors of childhood cancer currently use irradiated regions (IR) to determine risk for late effects. However, contemporary radiotherapy techniques utilize volumetric dosimetry (VD) to determine organ‐specific exposures, which could inform need for late effect surveillance.

Methods

This cross‐sectional cohort study involved patients treated for cancer using computerized tomography‐planned irradiation at Children's Hospital Los Angeles from 2000–2016. Organs at risk were identified using both VD and IR. Under each method, Children's Oncology Group Long‐Term Follow‐Up Guidelines were applied to determine radiation‐related potential late effects and their correlative recommended screening practices. Patients served as their own controls. Mean number of potential late effects per patient and recommended screening practices per patient per decade of follow‐up were compared using paired t‐tests; comparisons were adjusted for diagnosis and gender using random effects, repeated measure linear regression.

Results

In this cohort (n = 132), median age at end of treatment was 10.6 years (range, 1.4–20.4). Brain tumor was the most common diagnosis (45%) and head/brain the most common irradiated region (61%). Under IR and VD, the mean number of potential late effects flagged was 24.4 and 21.7, respectively (−11.3%, p < 0.001); concordance between the two methods was 6.1%. Under VD, the difference in mean number of recommended screening practices per patient was −7.4% in aggregate but as large as −37.0% for diagnostic imaging and procedures (p < 0.001 for both).

Conclusion

Use of VD rather than IR is feasible and enhances precision of guideline‐based screening for radiation‐related late effects in long‐term childhood cancer survivors.
Transcarotid versus transfemoral access in patients undergoing transcatheter aortic valve replacement with complex aortofemoral anatomy
Authors: Leclercq Florence , Choteau Romuald , Cayla Guillaume , Chamard Chloé , Lounes Youcef , Lattuca Benoit , Macia Jean‐Christophe , Delseny Delphine , Akodad Mariama , Gandet Thomas
Published: December 2020

Aims

While major vascular complications (MVC) remains an issue after Transfemoral (TF) transcatheter aortic valve replacement (TAVR), we compared outcomes in TF versus transcarotid (TC) approaches in patients with complex vascular anatomy.

Methods and results

Among patients undergoing TAVR in our center between 2015 and 2018, we evaluated patients with complex vascular anatomy defined on CT scan as: (a) iliofemoral diameter between 5.5 and 6 mm or <6.5 mm with severe calcifications or tortuosity AND/OR (b) abdominal aorta pathology. The primary endpoint included access failure, mortality, MVC, major bleeding and stroke at 1‐month. Among 483 patients, 131 (31.2%) with complex vascular anatomy underwent TF (n = 51;39.2%) or TC (n = 80;60.8%) TAVR. The mean age was 81.7 ± 6.9. TC group had higher STS score (p = .01), higher incidence of coronary artery disease (p = .04) and lower left ventricular ejection fraction (p < .001). In TC group, primary endpoint occurred twice less without reaching significance compared to TF group (n = 8; 10.0% vs. n = 10; 19.6% respectively; p = .1). Incidence of MVC was higher in TF group (11.8 vs. 1.3% in the TC group; p = .01) with similar incidence of stroke between groups (p = .8).

Conclusions

Despite higher patient risk profile, TC approach in complex aortofemoral anatomy provides similar favorable outcomes with less MVC compared to TF approach.
Treatment of deep corneal ulcers with porcine small intestinal submusosa using a modified surgical technique in dogs
Authors: Steinmetz Andrea , Theyse Lars F.H.
Published: December 2020

Treatment of deep corneal ulcers using small intestinal submucosa (SIS) without corneal sutures in combination with a third eyelid flap seems a promising technical modification. Advantages are a reduction in surgery time and no additional damage of healthy corneal tissue.
Triphenylphosphine‐Functionalized Core‐Cross‐Linked Micelles and Nanogels with a Polycationic Outer Shell: Synthesis and Application in Rhodium‐Catalyzed Biphasic Hydrogenations
Authors: Wang Hui , Vendrame Lorenzo , Fliedel Christophe , Chen Si , Gayet Florence , D'Agosto Franck , Lansalot Muriel , Manoury Eric , Poli Rinaldo
Published: December 2020

Unimolecular amphiphilic nanoreactors with a poly(4‐vinyl‐N‐methylpyridinium iodide) (P4VPMe+I−) polycationic outer shell and two different architectures (core‐cross‐linked micelles, CCM, and nanogels, NG), with narrow size distributions around 130–150 nm in diameter, were synthesized by RAFT polymerization from an R0‐4VPMe+I−140‐b‐S50‐SC(S)SPr macroRAFT agent by either chain extension with a long (300 monomer units) hydrophobic polystyrene‐based block followed by cross‐linking with diethylene glycol dimethacrylate (DEGDMA) for the CCM particles, or by simultaneous chain extension and cross‐linking for the NG particles. A core‐anchored triphenylphosphine (TPP) ligand functionality was introduced by using 4‐diphenylphosphinostyrene (DPPS) as a comonomer (5–20 % mol mol−1) in the chain extension (for CCM) or chain extension/cross‐linking (for NG) step. The products were directly obtained as stable colloidal dispersions in water (latexes). After loading with [RhCl(COD)]2 to yield [RhCl(COD)(TPP@CCM)] or [RhCl(COD)(TPP@NG)], respectively, the polymers were used as polymeric nanoreactors in Rh‐catalyzed aqueous biphasic hydrogenation of the model substrates styrene and 1‐octene, either neat (for styrene) or in an organic solvent (toluene or 1‐nonanol). All hydrogenations were rapid (TOF up to 300 h−1) at 25 °C and 20 bar of H2 pressure, the biphasic mixture rapidly decanted at the end of the reaction (<2 min), the Rh loss was negligible (<0.1 ppm in the recovered organic phase), and the catalyst phase could be recycled 10 times without significant loss of catalytic activity.
Acly promotes metabolic reprogramming and induction of IRF4 during early CD8+ T cell activation
Authors: Vaughn Nicole , Haviland David L.
Published: December 2020

CD8+ T cells, a fundamental part of the adaptive immune system, employ cytotoxic responses important for targeting pathogenic bacteria, viruses, and tumor cells. During early activation, CD8+ T cells undergo many changes in metabolism and gene expression. The bridge between epigenetic and metabolic influences on gene expression and cell fate has yet to be fully understood. Here, we investigated the importance of ATP citrate lyase (Acly), an enzyme involved in both metabolism and histone acetylation, for early stages of CD8+ T cell activation. We performed polyclonal activation of murine CD8+ T cells in vitro in the presence or absence of the Acly inhibitor BMS303141. We found that inhibiting Acly during early activation results in decreased expression of early activation markers. Consistent with impaired early activation, we found that inhibition also resulted in increased uptake of fatty acids and decreased glucose uptake without changing mitochondrial ATP levels. On an epigenetic and transcriptional level, early stage Acly inhibition specifically downregulated promoter histone H3 acetylation (H3ac) and expression of the key transcription factor IRF4; however, global levels of H3ac remained similar. Most importantly, the study was able to highlight the importance of Acly in early stages of CD8+ T cell activation and histone regulation.
Altered hippocampal microstructure and function in children who experienced Hurricane Irma
Authors: Conley May I. , Skalaban Lena J. , Rapuano Kristina M. , Gonzalez Raul , Laird Angela R. , Dick Anthony Steven , Sutherland Matthew T. , Watts Richard , Casey B.J.
Published: December 2020

Hurricane Irma was the most powerful Atlantic hurricane in recorded history, displacing 6 million and killing over 120 people in the state of Florida alone. Unpredictable disasters like Irma are associated with poor cognitive and health outcomes that can disproportionately impact children. This study examined the effects of Hurricane Irma on the hippocampus and memory processes previously related to unpredictable stress. We used an innovative application of an advanced diffusion‐weighted imaging technique, restriction spectrum imaging (RSI), to characterize hippocampal microstructure (i.e., cell density) in 9‐ to 10‐year‐old children who were exposed to Hurricane Irma relative to a non‐exposed control group (i.e., assessed the year before Hurricane Irma). We tested the hypotheses that the experience of Hurricane Irma would be associated with decreases in: (a) hippocampal cellularity (e.g., neurogenesis), based on known associations between unpredictable stress and hippocampal alterations; and (b) hippocampal‐related memory function as indexed by delayed recall. We show an association between decreased hippocampal cellularity and delayed recall memory in children who experienced Hurricane Irma relative to those who did not. These findings suggest an important role of RSI for assessing subtle microstructural changes related to functionally significant changes in the developing brain in response to environmental events.
Dynamic and precise temperature control unit for PEMFC single‐cell testing
Authors: Sabawa Jarek P. , Haimerl Felix , Riedmann Felix , Lochner Tim , Bandarenka Aliaksandr S.
Published: December 2020

The performance and durability of polymer electrolyte membrane (PEM) fuel cells is sensitive to the operating temperature. In order to optimize the operation strategy of PEM fuel cells, it is essential to perform various stress tests within wide temperature ranges. Nevertheless, not all types of stress tests can be performed on the standard single‐cells. For the low‐temperature tests, an additional cooling device is needed, which is associated with high costs and long testing times. In this work, two high power temperature control units were developed. With the small‐size (50 cm2) and automotive‐size (285 cm2) designs, the PEM fuel cell tests at temperatures well below 0°C are possible with the temperature change rates of 80 K min−1. In addition to the high dynamics, the automotive design allows to set the temperature gradients over the active surface area. This offers the possibility to simulate different alteration effects, which can occur during normal operation and increases the comparability between the fuel cell single‐cells and stacks.
Investigation of the impact of EU and governmental measures on the spread and the energy supply of electromobility in Hungary
Authors: Árpád István , T. Kiss Judit , Bellér Gábor , Kocsis Dénes
Published: December 2020

The fight against climate change has brought new technical solutions in the energy industry and transport. Carbon‐neutral solutions, the use of renewable energies have become preferred. Recently, the spread of electromobility in road transport has been increasing worldwide. This situation means new challenges for the energy industry and transport infrastructure. The direction of the development of the society, the energy industry, and the transport is influenced by the governments too. The article studies the governmental and international regulations, guidelines, and plans from the point of view on how these affect the development of transport in Hungary. The authors model the expected spread of electromobility in Hungary. In addition, the authors examine the expected structural transformation of electricity generation, the change expected in the energy mix. Finally, the government's plans are assessed, and it is discussed how Hungary can meet its commitments on renewable energy sources.
Hidden in plain sight: A microanalytical study of a Middle Stone Age ochre piece trapped inside a micromorphological block sample
Authors: Haaland Magnus M. , Strauss André M. , Velliky Elizabeth C. , Mentzer Susan M. , Miller Christopher E. , van Niekerk Karen L. , Henshilwood Christopher S.
Published: December 2020

A complete Middle Stone Age ochre piece was unintentionally collected and fully preserved within a micromorphological block sample intended to characterise a 74 ± 3 ka occupation horizon at Blombos Cave, South Africa. Previously recovered ochre pieces from the same stratigraphic context (Still Bay) have displayed intricate modification patterns with significant behavioural implications. Yet, in the case of the trapped ochre, a direct visual assessment of its surfaces was impossible due to its impregnated state. In this study, we demonstrate how we successfully reconstructed three‐dimensionally and characterised the block‐sampled ochre piece using high‐resolution microcomputed tomography scanning coupled with a range of microanalytical techniques, including optical petrography, micro‐Fourier transform infra‐red spectroscopy, micro‐X‐ray fluorescence and micro‐Raman spectroscopy. Through a morphometric analysis of the score marks present on the trapped ochre's reconstructed surface, we were able to assess the types of modifications and the nature of the actions that created them. Our results show that a block sample‐based study of archaeological artefacts allows for a comprehensive assessment of their depositional and microcontextual setting, their external morphology and microtopography, as well as their internal texture and geochemical properties. We suggest that this type of context‐sensitive, multiscalar and multidisciplinary investigation may also prove beneficial in the study of conventionally recovered archaeological artefacts.
Cardiorespiratory fitness, hippocampal subfield volumes, and mnemonic discrimination task performance in aging
Authors: Kern Kathryn L. , Storer Thomas W. , Schon Karin
Published: December 2020

Aging and exercise have opposing effects on mnemonic discrimination task performance, which putatively taxes pattern separation mechanisms reliant on the dentate gyrus (DG) subfield of the hippocampus. In young adults, increasing cardiorespiratory fitness (CRF) has been shown to improve mnemonic discrimination task performance and increase left anterior DG/CA3 volume. It is unknown how these variables interact in cognitive aging, yet this knowledge is critical, given the established effects of aging on hippocampal plasticity. To investigate these relationships, 65 older adults (aged 55–85 years) completed a submaximal treadmill test to estimate CRF, a mnemonic discrimination task, and a high‐resolution MRI scan to determine hippocampal subfield volumes. Our older adult sample demonstrated the lowest task accuracy in the condition with the greatest stimuli similarity and left DG/CA3 body volume significantly predicted accuracy in this condition. Our results did not provide support for relationships between CRF and task accuracy or CRF and DG/CA3 volume as evidenced in studies of young adults. Instead, CRF predicted bilateral subiculum volume in older adult women, not men. Altogether, these findings provide further support for a role of the DG in behavioral pattern separation in humans and suggest that CRF may have differential effects on hippocampal subfield integrity in older adult men and women.ClinicalTrials.govidentifiers: (a) Neuroimaging Study of Exercise and Memory Function, NCT02057354; (b) The Entorhinal Cortex and Aerobic Exercise in Aging, NCT02775760; (c) Physical Activity and Cognition Study, NCT02773121.
Importance of dose in palliative treatment for incurable head and neck cancer with radiotherapy
Authors: García‐Anaya María J. , Ordoñez Rafael , Toledo María D. , Correa Raquel C. , Otero Ana , Román Alicia , García‐Ríos Isabel , Medina José A. , Gómez‐Millán Jaime
Published: December 2020

Purpose

To identify predictors of palliation for head and neck cancer treated with the “Hypo Trial” hypofractionated radiation therapy regimen in a clinical setting.

Design/Method

We retrospectively assessed 106 consecutive patients with incurable cancer, treated between January 2008 and December 2018. Regimen used was 30‐36Gy in 5‐6 biweekly fractions of 6Gy.

Results

The prescription dose was 30Gy in 57 (53.8%) patients and 36Gy in 49 (46.2%) patients. 89.6% patients completed the prescribed treatment. With a median follow‐up of 6.92 months, 79.2% of the patients experienced clinical palliation. Palliation was correlated with the radiation therapy dose (P = 0.05). Median overall and progression‐free survival (OS, PFS) were 7 and 4.63 months, respectively. Achieving palliation was associated to OS (P = 0.01).

Conclusions

This short palliative hypofractionated scheme resulted in a high rate of palliation, with excellent compliance and acceptable toxicity. Our results show that radiation dose is a predictive factor for palliation.
Practices in software testing in Cameroon challenges and perspectives
Authors: Maxime Carlos Tchinda , Ibrahim Moukouop Nguena
Published: December 2020

Many software projects in Cameroon and elsewhere fail to produce the desired quality product due to low adoption of good software testing practices, including test automation. The fundamental questions are what are the local barriers to adopting structured approaches to specifying test cases? And what obstacles are preventing software testing from being automated? To answer these questions, this study analyzes software testing practices in Cameroon. The ultimate objective is to issue recommendations on the directions in which to direct research on software testing, in order to provide solutions promoting the adoption of good testing practices in projects, taking into account limited financial and human resources in developing countries. To do this, a survey was carried out among companies that carry out software development activities. The analysis of the results obtained reveals several interesting elements among which we can cite: (a) more than 80% of the respondents do not ensure that there has been a test other than that of the developer who does not follow a structured approach, (b) automated tests represent less than 8% of the number of tests carried out, (c) the most recurrent factors against test automation are the time required to configure or adapt the tools, the acquisition and implementation costs, costs of design, development, and maintenance of test cases.
Investigation of dengue–malaria coinfection among febrile patients consulting at Ngaoundere Regional Hospital, Cameroon
Authors: Galani Borris R. T. , Mapouokam Danielle W. , Simo Fredy B. N. , Mohamadou Hassimi , Chuisseu Pascal D. D. , Njintang Nicolas Y. , Moundipa Paul F.
Published: December 2020

This study aimed at evaluating the seroprevalence of dengue among malarious patients consulting at the Ngaoundere Regional Hospital. During 2 months and a half, 174 participants were recruited and their blood samples were screened forPlasmodiumspp and then forDenguevirus (DENV) infection using rapid diagnostic tests. Also, hematological asparameters were measured using a hematology autoanalyzer. Among patients tested, 134 (77.01%) were malaria‐positive, and 12/134 (8.95%) were coinfected. In this population, 8/12 (66.67%) were only anti‐DENV IgM‐positive, 3/12 (25%) were both NS1 and anti‐DENV IgM positive, and 1/12 (8.33%) were anti‐DENV IgG‐positive. Furthermore, women were more affected (58.3%) than men (41.7%). The most affected age groups were young people aged less than or equal to 15 years (33.3%) and adults aged between 30 and 45 years (33.3%). A significant association (p < .05; odds ratio [OR] = 5.16) was found between the age range (30–45) and dengue–malaria coinfection. Similarly, we noted a significant association between the coinfection, and joint pain (p < .05; OR = 6.15), fatigue (p < .01; OR = 5.74), and chills (p < .05; OR = 0). Analysis of hematologic parameters showed a significant decrease (p < .001) in platelets in coinfected patients compared with monoinfected patients. In conclusion, dengue–malaria coinfection is a reality in Ngaoundere city and associated with the appearance of clinical features which predict the disease severity.
Autonomous in situ measurements of freshwater alkalinity
Authors: Shangguan Qipei , Lai Chun‐Ze , Beatty Cory M. , Young Fischer L. , Spaulding Reggie S. , DeGrandpre Michael D.
Published: December 2020

Total alkalinity (AT) is an important parameter in the study of aquatic biogeochemical cycles, chemical speciation modeling, and many other important fundamental and anthropogenic (e.g., industrial) processes. We know little about its short‐term variability, however, because studies are based on traditional bottle sampling typically with coarse temporal resolution. In this work, an autonomous AT sensor, named the Submersible Autonomous Moored Instrument for Alkalinity (SAMI‐alk), was tested for freshwater applications. A comprehensive evaluation was conducted in the laboratory using freshwater standards. The results demonstrated excellent precision and accuracy (± 0.1%–0.4%) over the AT range from 800 to 3000 μmol L−1. The system had no drift over an 8 d test and also demonstrated limited sensitivity to variations in temperature and ionic strength. Three SAMI‐alks were deployed for 23 d in the Clark Fork River, Montana, with a suite of other sensors. Compared to discrete samples, in situ accuracy for the three instruments were within 10–20 μmol L−1 (0.3–0.6%), indicating good performance considering the challenges of in situ measurements in a high sediment, high biofouling riverine environment with large and rapid changes in temperature. These data reveal the complex AT dynamics that are typically missed by coarse sampling. We observed AT diel cycles as large as 60–80 μmol L−1, as well as a rapid change caused by a runoff event. Significant errors in inorganic carbon system modeling result if these short‐term variations are not considered. This study demonstrates both the feasibility of the technology and importance of high‐resolution AT measurements.
Direct 3D Printing of Poly(lactic acid) on Cotton Fibers: Characterization of Materials and Study of Adhesion Properties of the Resulting Composites
Authors: Redondo Franco Leonardo , Giaroli María Carolina , Villar Marcelo Armando , de Freitas Augusto Gonzaga Oliveira , Ciolino Andrés Eduardo , Ninago Mario Daniel
Published: December 2020

The aim of this work is focused on the direct 3D‐printing of poly(lactic acid) (PLA) on a cotton textile substrate, and the study of the printing parameters that modify their adhesion. PLA samples are printed by using Fused Deposition Modeling technique (FDM), and three filling printing directions (45, 90 and 180°) are analyzed. The effectiveness of polymer deposition onto fabrics is studied by peeling tests. Adhesion tests revealed that samples printed with a filling direction of 45° presented the maximum adhesion force and separation energies twice higher than samples printed at 180°. These results suggest that printing at 45° filling direction results in higher entanglements between cotton fibers and printed polymer chains, by enhancing the interaction of both materials.
Preparation and Characterization of an Immobilized Enological Pectinase on Agar‐Alginate Beads
Authors: Martín María Carolina , DellÓlio Germán Ariel Gorri , Villar Marcelo Armando , Morata Vilma Inés , López Olivia Valeria , Ninago Mario Daniel
Published: December 2020

A commercial enological pectinase is immobilized on agar‐sodium alginate hydrogel beads via external gelation technique. Biocatalyst surface and their internal morphology are characterized by Scanning Electron Microscopy and a good enzyme distribution throughout mixt biopolymer matrix is observed. The biocatalyst is characterized by Fourier Transform Infrared Spectroscopy, confirming the presence of absorption bands associated with amino groups present in the enzyme. Mechanical performance of beads is followed by Texture Profile Analysis and it is demonstrated that agar‐alginate beads exhibited a hardness 3.8 times higher than agar beads. Enzymatic activity of the immobilized pectinase prepared under the optimal conditions reached 0.592 ± 0.041 U per grams of beads. Reusability studies indicated that the immobilized pectinase retained 61% of its initial activity after six successive cycles. The use of the developed biocatalyst decreased significantly the turbidity values after grape must is treated for 120 min at 20 °C. Due to these good properties, the immobilized pectinase synthetized in this work may find applications in the clarification process of winemaking.
Assessment of Biocompatibility and Vascular Effects of Polymeric Materials Using Chick Chorioallantoic Membrane, an Alternative Method
Authors: Dourado Lays Fernanda Nunes , da Silva Carolina Nunes , Arribada Raquel Gregorio , Júnior Armando da Silva Cunha
Published: December 2020

During the development of polymeric wound coating materials, the in vivo reactions play a key role in the success of the material for tissue engineering. In this work, the chick chorioallantoic membrane (CAM) model is highlighted as an alternative test to evaluate the biocompatibility and changes through the vascular network topography of CAM after the incubation with polymeric membranes. The eggshells of fertilized chicken eggs are opened on the third day of embryo development and the CAM is exposed. Polymeric membranes are placed on the CAM surface and incubated for 96 h. After, the CAM is photographed, the vessels are quantified and histological sections are prepared. In the groups that received spunbonded and cellulose, it is possible to observe tissue growth of the CAM involving the membranes. Regarding the changes in the vascular metrics, a significant increase in the total vessel length and the number of junctions is detected for the spunbonded group. Also, there is an expressive decrease of the lacunarity for this group. Histological analysis revealed an increase of new vessels on the spunbonded, which corroborates to the results mentioned before. The results obtained point out that the CAM assay provides a new perspective on the biocompatibility tests.
Physical, Chemical, Mechanical, and Microstructural Characterization of Banana Pseudostem Fibers from Musa Sapientum
Authors: Silva Fernanda Souza , Ribeiro Carlos Eduardo Gomes , Demartini Tcharllis João da Cunha , Rodríguez Rubén Jesus Sánchez
Published: December 2020

The analysis and exploration of natural fibers in the field of polymer composites contribute to the development of new natural reinforcement materials. This project's purpose is to evaluate the physical (density, diameter, water absorption, and contact angle), chemical (FTIR and TGA), and mechanical properties (tensile strength and pull‐out testing), as well as the microstructural characteristics (confocal laser and electron scanning microscopy) of the pseudostem fiber of the banana type “Bluggoe” (Musa sapientum). The goal is to evaluate its possible applications in the field of polymer compounds based on the observations. The results showed that the fibers presented physical, chemical, and mechanical properties within the expected results for natural fibers. The banana pseudostem fiber presented density of 0.22g/cm³; 49.51% in mass of cellulose, 27.80% of hemicellulose, and 27.77% of lignin; the diameter measurements are 0.293 ± 0.091 mm; and the strength tests have values of 583.46 ± 302.26 MPa. The banana pseudostem‐fiber results are compared to those of other researchers of natural fibers; it is concluded that these banana fibers can be a suitable alternative source to synthetic fibers, and can then be used as reinforcement in laminated composites.
Reclaiming of Vulcanized Rubber Foam Waste from the Shoe Industry Through Solid‐state Shear Extrusion and Compounding with SBR
Authors: Tozzi Kaique Afonso , Canto Leonardo Bresciani , Scuracchio Carlos Henrique
Published: December 2020

The recycling of vulcanized rubber has received intensive attention from the scientific community for many years and yet the disposal of this type of waste remains a subject of major concern. In this study, vulcanized rubber foam waste from the shoe industry is thermo‐mechanically reclaimed through solid‐state shear extrusion (SSSE) with the use of an intermeshing co‐rotating twin‐screw extruder operated at three different temperatures (100 °C, 120 °C and 140 °C). The resulting microstructural, physical and thermal properties are investigated. In addition, compounds based on styrene‐butadiene rubber (SBR) filled with non‐reclaimed and reclaimed rubber foam wastes are compounded in a two‐roll mill and their vulcanization behavior is evaluated by differential scanning calorimetry (DSC) and oscillating disc rheometry (ODR). The crosslinking density and tensile properties of vulcanized hot‐pressed molded compounds are also evaluated. The compounds filled with the reclaimed rubber foam wastes have higher values for the tensile strength and elongation at break compared with the compounds containing the non‐reclaimed waste. The E‐100 modulus remained the same for the different compositions and the best overall performance is achieved for the compound filled with the rubber foam waste reclaimed at 100 °C. This is attributed to the lower crosslink density, which improves the compound homogeneity, as well as the faster revulcanization kinetics of this compound.
Electrostatic or Steric Stabilization of the Cellulose Nanostructures Using Different Modifying Agents
Authors: Camani Paulo Henrique , de Souza Alana Gabrieli , Rosa Derval dos Santos
Published: December 2020

Cellulose nanostructures (CNSs) are nanoscale biomaterials that have an excellent reinforcing ability; however, due to their high hydrophilic nature, its functionalization is necessary to improve the compatibility between CNS and polymeric matrices. In this work, the CNS‐functionalization with four different modifiers: cationic (CS), anionic (AS), and non‐ionic (NS) surfactant, and GA (grafting agent) is proposed. The modification is conducted in aqueous solution, using three different modifiers contents: 1, 3, and 5 wt%. The modified‐CNS are characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray photoelectron spectroscopy (XPS), zeta potential (ζ), dynamic light scattering (DLS), and thermogravimetric analysis (TGA). CS and AS modifiers acted as electrostatic stabilizers, through charges present in its functional groups (NH3+ and SO3−, respectively); in this case, ζ and XPS results investigated the stabilization. NS and GA modifiers acted as steric stabilizers, due to their polymeric chains, which induces the repulsion between the CNS; the stabilization is confirmed mainly by DLS and XPS. Regarding thermal stability, modified‐CNS samples showed a slight decrease in thermal properties due to the presence of reactive groups in the modifiers. All the samples showed the potential to be applied as fillers in nanocomposites, with degradation temperatures above the biopolymers processing temperatures.
3D Printed Parts of Polylactic Acid Reinforced with Carbon Black and Alumina Nanofillers for Tribological Applications
Authors: Cardoso Paulo Henrique Machado , de Oliveira Marcelo Ferreira Leão , de Oliveira Marcia Gomes , da Silva Moreira Thiré Rossana Mara
Published: December 2020

3D printing plays an important role in Industry 4.0 and has versatility to use different materials, including thermoplastic polymers. Polylactic acid (PLA), a bio‐based biodegradable polymer, is used as a potential replacement for petroleum‐based polymers in several applications, and is one of the most popular polymers used in 3D printing. Inorganic/organic nanoparticles can be incorporated in polymers to improve various properties such as thermal, mechanical, and tribological. This work investigates the effect of adding carbon black (CB) and alumina (ALM) nanofillers on the thermal, mechanical, and tribological properties of 3D printed PLA nanocomposites for tribological applications. Both nanofillers promoted progressive enhancement of thermal stability according to TGA. The improvement in the interaction between nanofillers and PLA matrix is revealed by an increase in viscosity of the nanocomposites. The nanocomposites containing 25%wt ALM and 75wt% CB presented better mechanical and wear properties, suggesting synergism between nanofillers and that CB may act as a compatibilizer between PLA and ALM. These results enable selecting the most suitable composition of nanofillers to be added to PLA to create filaments with better tribological properties.
Emerging roles of SIRT6 in human diseases and its modulators
Authors: Liu Gang , Chen Haiying , Liu Hua , Zhang Wenbo , Zhou Jia
Published: December 2020

The biological functions of sirtuin 6 (SIRT6; e.g., deacetylation, defatty‐acylation, and mono‐ADP‐ribosylation) play a pivotal role in regulating lifespan and several fundamental processes controlling aging such as DNA repair, gene expression, and telomeric maintenance. Over the past decades, the aberration of SIRT6 has been extensively observed in diverse life‐threatening human diseases. In this comprehensive review, we summarize the critical roles of SIRT6 in the onset and progression of human diseases including cancer, inflammation, diabetes, steatohepatitis, arthritis, cardiovascular diseases, neurodegenerative diseases, viral infections, renal and corneal injuries, as well as the elucidation of the related signaling pathways. Moreover, we discuss the advances in the development of small molecule SIRT6 modulators including activators and inhibitors as well as their pharmacological profiles toward potential therapeutics for SIRT6‐mediated diseases.
Trio‐WES reveals a novel de novo missense mutation of KMT2A in a Chinese patient with Wiedemann‐Steiner syndrome: A case report
Authors: Wang Xiong , Zhang Guijiao , Lu Yanjun , Luo Xiaoping , Wu Wei
Published: December 2020

Background

Wiedemann‐Steiner Syndrome (WSS) is an autosomal dominant genetic condition caused by mutations in the KMT2A gene. Lysine methyltransferase, encoded by KMT2A, plays critical roles in the regulation of gene expression during early development.

Methods

Trio‐based whole exome sequencing (Trio‐WES) was performed on a 15 months old Chinese girl and her two parents by MyGenostics (Beijing, China) using the Illumina HiSeq X ten system. Variants were confirmed with Sanger sequencing. She exhibited mild/moderate intellectual disability (ID), hypotonia, hypertrichosis cubiti, hypertrichosis on the back, dysmorphic facies, psychomotor retardation, growth delay, small and puffy hands, fat pads anterior to calcanei, and palmar/plantar grooves.

Results

Trio‐WES revealed a novel de novo mutation of KMT2A gene (NM_001197104.1: c.3566G>T, p.Cys1189Phe). WSS was diagnosed based on WES and clinical features.

Conclusion

Our findings expand the phenotypic and mutation spectra of WSS.
Rapid measurement of the low contrast detectability of CT scanners
Authors: Omigbodun Akinyinka , Vaishnav J. Y. , Hsieh Scott S.
Published: December 2020

Purpose

Low contrast detectability (LCD) is a metric of fundamental importance in computed tomography (CT) imaging. In spite of this, its measurement is challenging in the context of nonlinear data processing. We introduce a new framework for objectively characterizing LCD with a single scan of a special‐purpose phantom and automated analysis software. The output of the analysis software is a “machine LCD” metric which is more representative of LCD than contrast‐noise ratio (CNR). It is not intended to replace human observer or model observer studies.

Methods

Following preliminary simulations, we fabricated a phantom containing hundreds of low‐contrast beads. These beads are acrylic spheres (1.6 mm, net contrast ~10 HU) suspended and randomly dispersed in a background matrix of nylon pellets and isoattenuating saline. The task was to search for and localize the beads. A modified matched filter was used to automatically scan the reconstruction and select candidate bead localizations of varying confidence. These were compared to bead locations as determined from a high‐dose reference scan to produce free‐response ROC curves. We compared iterative reconstruction (IR) and filtered backpropagation (FBP) at multiple dose levels between 40 and 240 mAs. The scans at 60, 120, and 180 mAs were performed three times each to estimate uncertainty.

Results

Experimental scans demonstrated the feasibility of our technique. Our metric for machine LCD was the area under the exponential transform of the FROC curve (AUC). AUC increased monotonically from 0.21 at 40 mAs to 0.84 at 240 mAs. The sample standard deviation of AUC was approximately 0.02. This measurement uncertainty in AUC corresponded to a change in tube current of 4% to 8%. Surprisingly, we found that AUCs for IR were slightly worse than AUCs for FBP. While the phantom was sufficient for these experiments, it contained small air bubbles and alternative fabrication methods will be necessary for widespread utilization.

Conclusions

It is feasible to measure machine LCD using a search task on a phantom with hundreds of beads and to obtain tight error bars using only a single scan. Our method could facilitate routine quality assurance or possibly enable comparisons between different protocols and scanners.
Managing uncommon and unexpected findings during neuromuscular ultrasound
Authors: Walker Francis O. , Cartwright Michael S. , Hunt Christopher H.
Published: December 2020

One barrier to widespread adoption of neuromuscular ultrasound by clinical neurophysiologists is concern over how to identify and manage non‐neuromuscular findings. This review addresses this concern by describing the sonographic appearance of a variety of commonly observed pathologies and anatomic variants in dermal, subcutaneous, bony, glandular, lymphatic, vascular, and other superficial tissues. Additionally, it outlines techniques to ensure proper clinical and ultrasound evaluation of unexpected or uncommon findings. Finally, it highlights strategies to manage unexpected findings, including how to best communicate findings to patients and referring clinicians to avoid unnecessary testing and ensure appropriate follow‐up. Ultrasound extends the ability of the neuromuscular sonographer‐clinician to contribute to patient care.
Accurate numerical integration for the quadrilateral and hexahedral finite elements
Authors: Xie Ziqing , Zhang Shangyou
Published: December 2020

The numerical integration for the bilinear form of quadrilateral or hexahedral finite elements can never be exact. It is discovered that the standard Gauss‐Legendre integration is exact if one of the two Qk polynomials in the bilinear form is a Pk polynomial. Based on this observation, it is proved the Qk finite elements, under practical numerical integration, retain the optimal order of convergence on general quadrilateral grids in 2 dimensional space, and on general hexahedral grids in 3 dimensional space. Numerical tests are provided, verifying all theoretic findings.
Nigeria's #EndSARS movement and its implication on online protests in Africa's most populous country
Authors: Dambo Tamar Haruna , Ersoy Metin , Auwal Ahmad Muhammad , Olorunsola Victor Oluwafemi , Olonode Ayodeji , Arikewuyo Abdulgaffar Olawale , Joseph Ayodele
Published: December 2020

Modern tools of connectivity have afforded disadvantaged youth across the globe the opportunity to collectively share and curate challenges and build up strategies to protest marginalization. This argument is however sharply divided between tech‐optimists, who argue that social media remove all forms of barrier and empower average members of society and tech‐pessimists who argue that social media discourage people from actively seeking change. This article wades into this discourse by looking at the claims of police abuse by Nigerian youth on social media. For decades, police abuse of powers has remained a subject of interest in academic and human rights circles. This interest has perhaps been amplified by online social movements. In Nigeria, this abuse is well documented in the #EndSARS campaign, which has lasted for three years with little success. In disparity to most academic studies that investigate success of online movement, this study critically inspects the limitation of the #EndSARS campaign by assessing how Nigeria's political environment can serve as a possible hindrance to successful movements. This research therefore answers two questions: What are the dominant themes in Nigeria's #EndSARS campaign? What are the limitations to activism in Nigeria?
Role of public health and trade for achieving sustainable development goals
Authors: Nazar Raima , Meo Muhammad Saeed , Ali Sajid
Published: December 2020

The United Nations General Assembly adopted “2030 agenda” for Sustainable Development Goals (SDGs) with the objective of “transforming our world.” Provision of health and trade services is central in SDGs. This study focuses on broad objectives of public health and trade, which would significantly contribute to satisfying the health and trade‐related targets of the SDGs. The paper outlines the key provisions in recent trade agreements that constrain policy space for implementing universal health coverage. It focuses on actions of relevance to health innovations and access to health products with the contribution of health and trade policies. Regarding innovation, short‐term, mid‐term and long‐term measures are proposed concerning the General Agreement on Trade in Services, Agreement on Subsidies and Countervailing Measures and Agreement on Trade‐Related Aspects of Intellectual Property Rights (TRIPS). For intellectual property, four actions are proposed, which are empiric assessments; adoption of an integrated approach; intensive use of the TRIPS flexibilities and agreeing on the meaning of pharmaceutical innovation.