bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of Water Content on the Acid Number of Diesel Engine Lubricant in Electrochemical Measurement
Authors: Zhou Fanhao , Yang Kun
Published: February 2021

Acid Number is one of the important characteristics of lubricating oil. In this study, thick film (TF) potentiometric sensors based on ion-selective electrodes (ISE) were used to determine the acid acidity of the diesel engine oil to determine the oxidation duration of the oil. This is a real-time online detection method. Two working electrodes (polymer electrode and glass electrode) and a reference electrode (bare Ag electrode) were fabricated, and the acid acidity of the diesel engine lubricant was expressed in the form of voltage, which overcomes the insufficiency of the titration endpoint in the titration method. Among oil products, most varieties only allow traces (water content below 0.3%) of moisture, and some oil products do not allow moisture. Water in oil can emulsify diesel engine lubricant, decompose additives, promote the oxidation of oil products. It affects the low-temperature fluidity of oil products. For transformer oil, extremely small amounts of water will seriously affect its insulation performance. In the experiment, the influences of water content for the acid acidity of the diesel engine lubricant were considered and tested.
The Influence of Nozzle Parameters on the Atomization Performance of Non-normal Fuel based on the Super-high Pressure Common Rail System
Authors: Liu Qi , Liu Yunsheng , Chen Xinzhuan , Huo Baiqi
Published: February 2021

The uniformity of the fuel and air mixture in the cylinder of diesel engine directly affects the smooth running of the combustion process. In order to improve the atomization effect of the fuel in the cylinder, the super-high injection pressure exceeding 180MPa was used. The changing relationship between the physical properties of the non-normal fuel and the pressure under the influence of the super-high injection pressure was derived. The three-dimension combustion model of TBD620 diesel engine is constructed on the FIRE software platform. A numerical simulation of the two injectors’ fuel injection process under different load conditions has been done in the research work. The fuel spray characteristics has been simulated. The results show that the special fuel injector has a good performance under low loading conditions, but the standard fuel injector has better performance for oil and gas fully mixed under high loading conditions.
INFLUENCE OF FEMTOSECOND LASER PROCESSING PARAMETERS ON THE SURFACE MORPHOLOGY AND WETTABILITY PROPERTIES OF POLYLACTIC ACID
Authors: Daskalova Albena , Angelova Liliya , Carette Xavier , Mincheva Rosica , Raquez Jean-Marie , Trifonov Anton , Buchvarov Ivan
Published: February 2021

Polylactic acid (PLA) is a very attractive material for applications in the field of regenerative medicine and tissue engineering, as it is a biocompatible and biodegradable synthetic polymer, whose morphological properties can be finely tuned via laser processing. Ultra-short pulse laser treatment is a non-invasive method for optimizing the surface properties of engineered biomatrices. The method offers controlled porosity of the treated biomaterial tailored specifically for implantation needs. In this research, we investigated the interaction of femtosecond laser radiation with PLA stacks while varying the output laser parameters in order to estimate their influence on the morphology of the PLA samples. The induced microstructural features were characterized by thickness measurements and SEM, EDX and FTIR analyses. In order to evaluate the hydrophilicity of the treated surface, water contact angle (WCA), measurements were also performed. Topography modification of the PLA substrates could essentially improve this material’s bioactivity properties, which, after proper optimization of the laser parameters, could make its biomedical applications even more successful.
Ultra-short laser pulse modification of chitosan/silver nanoparticles (AgNPs) thin films for potential antimicrobial applications
Authors: Iordanova E , Yankov G , Daskalova A , Dikovska A , Angelova L , Aceti D , Filipov E , Stanev G , Calin B , Zamfirescu M
Published: February 2021

The last several years witnessed increasingly rapid advances in applying biopolymers in tissue engineering for the purposes of regenerative medicine. The growing demand for preparing materials with desired physical, biological and mechanical properties requires active investigations in the field of tissue engineering. Among the wide variety of biopolymers, chitosan proved to be an outstanding material due to its properties, such as biocompatibility, biodegradability and a wide range of available fabrication technologies. The present work is a case study of an extensive research on the functionalization of thin biopolymer films via laser patterning. The aim of the current study is to investigate the optical properties of biopolymer films on the example of chitosan and chitosan with silver nanoparticles additives. As laser sources are used a nano- and a femto-second laser system emitting the wavelengths of 355 nm and 800 nm, respectively. The compositions produced are investigated by spectral analyses using spectrometers and an optical microscope. Furthermore, the morphology of the samples is monitored by SEM analyses. The results obtained demonstrate the potential of the method employed for obtaining diverse porous modifications depending on the laser parameters. Adding silver nanoparticles will drastically increase the thin chitosan films’ antimicrobial properties, thus enhancing the biocompatibility properties of the 2D matrices created.
Electron-beam surface alloying of Ti substrates with Ta films
Authors: Valkov S , Ormanova M , Bezdushnyi R , Petrov P
Published: February 2021

We report electron-beam surface alloying of Ti substrates with Ta. The Ti substrates were covered by a Ta coating with a thickness of 2 μm. The samples were alloyed by a scanning electron beam, with the beam deflection geometry in the shape of the infinity symbol (∞). Two experiments were implemented, where the width of the infinity symbol was kept constant at 8 mm, while the height was 8 mm for the first experiment and 4 mm for the second one. The phase composition of the specimens produced was studied by X-ray diffraction (XRD). The microstructure and chemical composition were investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), respectively. The results showed that the phase composition consisted of a double phase structure of α’ martensitic and of beta phases. Some amount of pure Ta remained in the alloyed layer produced by the first experiment. Also, the distribution of the alloying element into the substrate was significantly more homogeneous in the case of the second one.
Measuring, controlling and exploiting heterogeneity in optoelectronic nanowires
Authors: Al-Abri Ruqaiya , Choi Hoyeon , Parkinson Patrick
Published: February 2021

Fabricated from ZnO, III-N, chalcogenide-based, III-V, hybrid perovskite or other materials, semiconductor nanowires offer single-element and array functionality as photovoltaic, non-linear, electroluminescent and lasing components. In many applications their advantageous properties emerge from their geometry; a high surface-to-volume ratio for facile access to carriers, wavelength-scale dimensions for waveguiding or a small nanowire-substrate footprint enabling heterogeneous growth. However, inhomogeneity during bottom-up growth is ubiquitous and can impact morphology, geometry, crystal structure, defect density, heterostructure dimensions and ultimately functional performance. In this topical review, we discuss the origin and impact of heterogeneity within and between optoelectronic nanowires, and introduce methods to assess, optimise and ultimately exploit wire-to-wire disorder.
Primes in arithmetic progressions and semidefinite programming
Authors: Chirre Andrés , Pereira Júnior Valdir , de Laat David
Published: February 2021

Assuming the generalized Riemann hypothesis, we give asymptotic bounds on the size of intervals that contain primes from a given arithmetic progression using the approach developed by Carneiro, Milinovich and Soundararajan [Comment. Math. Helv. 94, no. 3 (2019)]. For this we extend the Guinand-Weil explicit formula over all Dirichlet characters modulo

q
≥
3

q \geq 3

, and we reduce the associated extremal problems to convex optimization problems that can be solved numerically via semidefinite programming.
Concave transforms of filtrations and rationality of Seshadri constants
Authors: Küronya Alex , Maclean Catriona , Roé Joaquim
Published: February 2021

We show that the subgraph of the concave transform of a multiplicative filtration on a section ring is the Newton–Okounkov body of a certain semigroup, and if the filtration is induced by a divisorial valuation, then the associated graded algebra is the algebra of sections of a concrete line bundle in higher dimension. We use this description to give a rationality criterion for certain Seshadri constants.
Quantitative visualization of endocytic trafficking through photoactivation of fluorescent proteins
Authors: Ecker Manuela , Redpath Gregory M. I. , Nicovich Philip R. , Rossy Jérémie
Published: February 2021

Endocytic trafficking controls the density of molecules at the plasma membrane which determines how cells interact with their environment. Here we present a toolset based on photoactivation of fluorescent proteins to generate quantitative information on endocytosis, sorting, and recycling and on the type of vesicles performing intracellular transport.
Look at the time!
Authors: Builes David
Published: February 2021

I argue that we can get evidence for the temporal ontology of the universe simply by looking at the time. The argument is an extension of the 'epistemic objection' towards Growing Block theories.
LncRNA small nucleolar RNA host gene 16 (SNHG16) silencing protects lipopolysaccharide (LPS)-induced cell injury in human lung fibroblasts WI-38 through acting as miR-141-3p sponge
Authors: Xia Lei , Zhu Guoqing , Huang Haiyun , He Yishui , Liu Xingguang
Published: February 2021

Long noncoding RNA (LncRNA) small nucleolar RNA host gene 16 (SNHG16) is correlated with cell injuries, including pneumonia. However, its role and mechanism remain vague in pneumonia. The interplay among genes was confirmed by dual-luciferase reporter assay, RNA immunoprecipitation, and RNA pull-down assay. SNHG16 and sushi domain containing 2 (SUSD2) were upregulated, and miRNA (miR)-141-3p was downregulated in the serum of acute pneumonia patients and lipopolysaccharide (LPS)-challenged human lung fibroblasts WI-38. LPS induced apoptosis, autophagy, and inflammatory response in WI-38 cells, which was significantly attenuated by SNHG16 knockdown and/or miR-141-3p overexpression. Notably, both SNHG16 and SUSD2 were identified as target genes of miR-141-3p. Besides, the suppressive role of SNHG16 knockdown in LPS-induced in WI-38 cells was partially abolished by miR-141-3p silencing, and the similar inhibition of miR-141-3p overexpression was further blocked by SUSD2 restoration. In conclusion, knockdown of SNHG16 could alleviate LPS-induced apoptosis, autophagy, and inflammation in WI-38 cells partially though the SNHG16/miR-141-3p/SUSD2 pathway.
Sphingosine-1-phosphate and its mimetic FTY720 do not protect against radiation-induced ovarian fibrosis in the nonhuman primate†
Authors: Amargant Farners , Manuel Sharrón L , Larmore Megan J , Johnson Brian W , Lawson Maralee , Pritchard Michele T , Zelinski Mary B , Duncan Francesca E
Published: February 2021

Oocytes are highly radiosensitive, so agents that prevent radiation-induced ovarian follicle destruction are important fertility preservation strategies. A previous study in rhesus macaques demonstrated that ovarian treatment with antiapoptotic agents, sphingosine-1-phosphate (S1P) and FTY720, its long-acting mimetic, preserved follicles following a single dose of 15 Gy X-ray radiation, and live offspring were obtained from FTY720-treated animals. However, it is unknown whether these antiapoptotic agents also protected the ovarian stroma from late effects of radiation, including vascular damage and fibrosis. Using ovarian histological sections from this study, we evaluated the vasculature and extracellular matrix in the following cohorts: vehicle + sham irradiation, vehicle + irradiation (OXI), S1P + irradiation (S1P), and FTY720 + irradiation (FTY720). One ovary from each animal was harvested prior to radiation whereas the contralateral ovary was harvested 10 months post-treatment. We assessed vasculature by immunohistochemistry with a PECAM1 antibody, hyaluronan by a hyaluronan binding protein assay, and collagen by picrosirius red and Masson’s trichrome staining. Disorganized vessels were observed in the medulla in the OXI and S1P cohorts relative to the sham, but the vasculature in the FTY720 cohort appeared intact, which may partially explain fertoprotection. There were no differences in the hyaluronan matrix among the cohorts, but there was thickening of the tunica albuginea and fibrosis in the OXI cohort relative to the sham, which was not mitigated by either S1P or FTY720 treatment. Thus, the fertoprotective properties of S1P and FTY720 may be limited given their inability to protect the ovarian stroma against the late effects of radiation-induced fibrosis.
This is Denmark: Prison Islands and the Detention of Immigrants
Authors: Barker Vanessa , Smith Peter Scharff
Published: February 2021

According to mainstream criminology, Nordic societies with their generous welfare states are supposed to moderate, if not restrict, penal powers. In the case of migration, we see the opposite pattern. In Denmark, we see extended use of penal institutions and penal harms to contain and remove unwanted populations from the region, including proposals for a prison island and the confinement of migrants in 19th century prisons. To make sense of these developments and interpret its social meaning, we unpack the logic of the punishment–welfare nexus and Nordic exceptionalism. We find that Denmark expands penal power to regulate non-citizens, deter migration and uphold national interests. These repressive practices are not exceptions to the rule but rather illustrate the exclusionary edge and very nature of the penal regimes in Denmark, a Nordic welfare state.
“It’s a Man Thing, Gina”: Watching Gender inMartin
Authors: Johnson Patrick
Published: February 2021

In the almost three decades since the hit situation-comedy Martin (1992–1997) originally aired on Fox, the show has not only enjoyed a vibrant second life through syndication and streaming platforms, but has functioned as a form of television heritage, reflected in fashion, music, games, and memes. Martin has developed a particularly loyal following among black millennials, many of whom were too young to watch the show during its original network television run. In this article, I explore the series’ representations of black women through individual and focus group interviews with 26 black viewers. My interviews reveal that participants have ambivalent relationships with the show. While several cite Martin as their favorite show of all-time, they were disturbed by the show’s troubling depictions of black heterosexual romantic relationships and its reliance on stereotypical representations of black women.
Safety and Pharmacokinetics of Double-Dose Lopinavir/Ritonavir + Rifampin Versus Lopinavir/Ritonavir + Daily Rifabutin for Treatment of Human Immunodeficiency Virus–Tuberculosis Coinfection
Authors: Kendall Michelle A , Lalloo Umesh , Fletcher Courtney V , Wu Xingye , Podany Anthony T , Cardoso Sandra W , Ive Prudence , Benson Constance A
Published: February 2021

Background

Protease inhibitor-based antiretroviral therapy may be used in resource-limited settings in persons with human immunodeficiency virus and tuberculosis (HIV-TB). Data on safety, pharmacokinetics/pharmacodynamics (PK/PD), and HIV-TB outcomes for lopinavir/ritonavir (LPV/r) used with rifampin (RIF) or rifabutin (RBT) are limited.

Methods

We randomized adults with HIV-TB from July 2013 to February 2016 to arm A, LPV/r 400 mg/100 mg twice daily + RBT 150 mg/day; arm B, LPV/r 800 mg/200 mg twice daily + RIF 600 mg/day; or arm C, LPV/r 400 mg/100 mg twice daily + raltegravir (RAL) 400 mg twice daily + RBT 150 mg/day. All received two nucleoside reverse transcriptase inhibitors and other TB drugs. PK visits occurred on day 12 ± 2. Within-arm HIV-TB outcomes were summarized using proportions and 95% CIs; PK were compared using Wilcoxon tests.

Results

Among 71 participants, 52% were women; 72% Black; 46% Hispanic; median age, 37 years; median CD4+ count, 130 cells/mm3; median HIV-1 RNA, 4.6 log10 copies/mL; 46% had confirmed TB. LPV concentrations were similar across arms. Pooled LPV AUC12 (157 203 hours × ng/mL) and Ctrough (9876 ng/mL) were similar to historical controls; RBT AUC24 (7374 hours × ng/mL) and Ctrough (208 ng/mL) were higher, although 3 participants in arm C had RBT Cmax <250 ng/mL. Proportions with week 48 HIV-1 RNA <400 copies/mL were 58%, 67%, and 61%, respectively, in arms A, B, and C.

Conclusions

Double-dose LPV/r+RIF and LPV/r+RBT 150mg/day had acceptable safety, PK and TB outcomes; HIV suppression was suboptimal but unrelated to PK. Faster RBT clearance and low Cmax in 3 participants on RBT+RAL requires further study.
In Utero Human Cytomegalovirus Infection Is Associated With Increased Levels of Putatively Protective Maternal Antibodies in Nonprimary Infection: Evidence for Boosting but Not Protection
Authors: Dorfman Jeffrey R , Balla Sashkia R , Pathirana Jayani , Groome Michelle J , Madhi Shabir A , Moore Penny L
Published: February 2021

Background

Although primary maternal cytomegalovirus infections are associated with higher risk of in utero transmission, most fetal infections worldwide result from nonprimary maternal infections. Antibodies directed at glycoprotein B (gB) and the gH/gL/pUL128–130–131 pentamer can neutralize virus, and higher levels of antibody directed at several particular pentamer epitopes defined by monoclonal antibodies (mAbs) are associated with reduced risk of fetal cytomegalovirus (CMV) transmission during primary maternal infection. This had not been explored in maternal nonprimary infection.

Methods

In a setting where most maternal CMV infections are nonprimary, 42 mothers of infants with congenital CMV infections (transmitters) were compared to 75 CMV-seropositive mothers whose infants were CMV-uninfected (nontransmitters). Control infants were matched by sex, maternal human immunodeficiency virus (HIV) status, and gestational age. We measured the ability of maternal antibodies to block 3 key pentameric epitopes: one in the gH subunit, another straddling UL130/UL131, and the third straddling gH/gL/UL128/UL130. We tested if levels of antibodies directed at these epitopes were higher in nontransmitters compared to transmitters.

Results

Levels of all 3 putatively protective pentamer-directed antibodies were significantly higher in transmitters compared to nontransmitters. In contrast, antibodies targeting an epitope on gB were not different. Total antibody specific for pentamer and for gB were also higher in transmitters.

Conclusions

We found no evidence that higher levels of any CMV-specific antibodies were associated with reduced risk of congenital CMV infection in nonprimary maternal infection. Instead, we found higher maternal antibody targeting epitopes on CMV pentamer in transmitters than nontransmitters, providing evidence for antibody boosting but not protection.
Digital Polymerase Chain Reaction for Assessment of Mutant Mitochondrial Carry-over after Nuclear Transfer for In Vitro Fertilization
Authors: Tytgat Olivier , Tang Mao-Xing , van Snippenberg Willem , Boel Annekatrien , Guggilla Ramesh Reddy , Gansemans Yannick , Van Herp Michiel , Symoens Sofie , Trypsteen Wim , Deforce Dieter , Heindryckx Björn , Coucke Paul , De Spiegelaere Ward , Van Nieuwerburgh Filip
Published: February 2021

Background

The quantification of mitochondrial DNA heteroplasmy for the diagnosis of mitochondrial disease or after mitochondrial donation, is performed mainly using next-generation sequencing strategies (NGS). Digital PCR (dPCR) has the potential to offer an accurate alternative for mutation load quantification.

Methods

We assessed the mutation load of 23 low-input human samples at the m.11778 locus, which is associated with Leber’s hereditary optic neuropathy (LHON) using 2 droplet digital PCR platforms (Stilla Naica and Bio-Rad QX200) and the standard NGS strategy. Assay validation was performed by analyzing a titration series with mutation loads ranging from 50% to 0.01%.

Results

A good concordance in mutation rates was observed between both dPCR techniques and NGS. dPCR established a distinctly lower level of background noise compared to NGS. Minor alleles with mutation loads lower than 1% could still be detected, with standard deviations of the technical replicates varying between 0.07% and 0.44% mutation load. Although no significant systematic bias was observed when comparing dPCR and NGS, a minor proportional bias was detected. A slight overestimation of the minor allele was observed for the NGS data, most probably due to amplification and sequencing errors in the NGS workflow.

Conclusion

dPCR has proven to be an accurate tool for the quantification of mitochondrial heteroplasmy, even for samples harboring a low mutation load (<1%). In addition, this alternative technique holds multiple benefits compared to NGS (e.g., less hands-on time, more straightforward data-analysis, and a lower up-front capital investment).
Systematic Review and Meta-analysis of Outcomes After Ileal Pouch-anal Anastomosis in Primary Sclerosing Cholangitis and Ulcerative Colitis
Authors: Barnes Edward L , Holubar Stefan D , Herfarth Hans H
Published: February 2021

Background

The optimal restorative surgical management of patients with concomitant diagnoses of primary sclerosing cholangitis and ulcerative colitis [PSC-UC] who require colectomy is controversial, given that patients may have an increased risk for pouchitis after ileal pouch-anal anastomosis [IPAA]. We aimed to compare rates of pouchitis and pouch failure among patients with and without PSC by performing a systematic review and meta-analysis.

Methods

A systematic search performed through August 18, 2020, identified 12 studies that compared the rates of pouchitis [n = 11] and/or pouch failure [n = 6] among patients with PSC-UC and UC alone. We then performed a meta-analysis using random effects modelling to estimate the odds of developing any episodes of pouchitis or pouch failure.

Results

A total of 4108 patients underwent an ileal pouch-anal anastomosis after proctocolectomy for UC. Of these, 3799 [92%] were performed for UC alone and 309 [8%] were performed for PSC-UC. In a meta-analysis of 11 studies, patients with PSC-UC compared with UC alone were significantly more likely to develop any pouchitis (63% vs 30%, odds ratio [OR] 4.21, 95% confidence interval [CI] 2.86–6.18), chronic pouchitis [47% vs 15%, OR 6.37, 95% CI 3.41–11.9], and pouch failure [10% vs 7%, OR 1.85, 95% CI 1.08–3.17].

Conclusions

Patients with PSC-UC were more likely to experience pouchitis and pouch failure than patients with UC alone. The risks of inflammatory complications after IPAA must be weighed against the potential complications with other surgical procedures, and future studies comparing outcomes among these procedures may inform decision making in this population.
Assessing proportionate and disproportionate functional mitral regurgitation with individualized thresholds
Authors: Lopes Pedro M , Albuquerque Francisco , Freitas Pedro , Gama Francisco , Horta Eduarda , Reis Carla , Abecasis João , Trabulo Marisa , Ferreira António M , Aguiar Carlos , Canada Manuel , Ribeiras Regina , Mendes Miguel , Andrade Maria J
Published: February 2021

Aims

The concept of proportionate/disproportionate functional mitral regurgitation (FMR) has been limited by the lack of a simple way to assess it and by the paucity of data showing its prognostic superiority. The aim of this study was to evaluate the prognostic value of an individualized method of assessing FMR proportionality.

Methods and results

We retrospectively identified 572 patients with at least mild FMR and reduced left ventricular ejection fraction (<50%) under medical therapy. To determine FMR proportionality status, we used an approach where a simple equation determined the individualized theoretical regurgitant volume (or effective regurgitant orifice area) threshold associated with haemodynamically significant FMR. Then, we compared the measured with the theoretical value to categorize the population into non-severe, proportionate, and disproportionate FMR. The primary endpoint was all-cause mortality. During a median follow-up of 3.8 years (interquartile range: 1.8–6.2), 254 patients died. The unadjusted mortality incidence per 100 persons-year rose as the degree of FMR disproportionality worsened. On multivariable analysis, disproportionate FMR remained independently associated with all-cause mortality [adjusted hazard ratio: 1.785; 95% confidence interval (CI): 1.249–2.550; P = 0.001]. The FMR proportionality concept showed greater discriminative power (C-statistic 0.639; 95% CI: 0.597–0.680) than the American (C-statistic 0.583; 95% CI: 0.546–0.621; P for comparison <0.001) and European guidelines (C-statistic 0.584; 95% CI: 0.547–0.620; P for comparison <0.001). When added to any of the before-mentioned guidelines, FMR proportionality also improved risk stratification by reclassifying patients into lower and higher risk subsets.

Conclusion

Disproportionate FMR is independently associated with all-cause mortality and improves the risk stratification of current guidelines.
Kindness as the Foundation to Community: For a ‘Radical Equality Tempered by Benevolence’. Joseph Rey of Grenoble (1779-1855)
Authors: Drolet Michael , Frobert Ludovic
Published: February 2021

This article examines the work of the jurist and political and social theorist, Joseph Rey. It explores Rey’s role within a French and international network of intellectuals and conspirators who sought to overthrow established monarchies and replace them with popularly elected democratic republics. The article shows how Rey’s extensive writings on legal, political, social and educational questions give a unique insight into France’s political, intellectual, social and ideological life in the first decades of the nineteenth century. We argue that Rey’s contribution to the debates that defined the modern ideological categories of liberalism, republicanism and socialism was significant in its endeavour to reconcile all three. This attempt at reconciliation was motivated by a powerful desire to end the internecine struggles that marked France in the aftermath of the Revolution and Empire. This led Rey to draw on the utilitarianism of Jeremy Bentham and the Philosophical Radicals in order to nourish a French republican liberalism rooted in the work of the Idéologues and combine this with his profound reading of Robert Owen’s work on co-operation. It goes on to show how Rey became known as France’s principal representative of Owenism, and sought to shape the debates between the dominant schools of French Socialist thought, Fourierism and Saint-Simonianism, by introducing into those discussions a radical conception of equality and the idea of co-operation. Rey’s attempts to reconcile the liberal-republican preoccupation with liberty and self-governance with socialist considerations on equality and social justice stand out from the works of his contemporaries. It is this unique, and long-forgotten, contribution to French and European political and social thought that makes Rey worthy of renewed attention.
Synchronous video computer-mediated communication in English language teaching
Authors: Kessler Matt , Loewen Shawn , Trego Daniel
Published: February 2021

In this series, we explore technology-related themes and topics. The series aims to discuss and demystify what may be new areas for some readers and to consider their relevance for English language teachers.
Cytokine storms, evolution and COVID-19
Authors: Alcock Joe , Masters Alix
Published: February 2021

Lay Summary

Many treatments for COVID-19 are aimed at calming a cytokine storm, a dangerous immune overreaction to the infection. Treating cytokine storms has been tried for decades in sepsis and other viral illnesses, but these treatments most often do not work. We explain why cytokine storms should be rare, and what special evolutionary circumstances can cause them to occur.
Split-wrmScarlet and split-sfGFP: tools for faster, easier fluorescent labeling of endogenous proteins in Caenorhabditis elegans
Authors: Goudeau Jérôme , Sharp Catherine S , Paw Jonathan , Savy Laura , Leonetti Manuel D , York Andrew G , Updike Dustin L , Kenyon Cynthia , Ingaramo Maria
Published: February 2021

We create and share a new red fluorophore, along with a set of strains, reagents and protocols, to make it faster and easier to label endogenous Caenorhabditis elegans proteins with fluorescent tags. CRISPR-mediated fluorescent labeling of C. elegans proteins is an invaluable tool, but it is much more difficult to insert fluorophore-size DNA segments than it is to make small gene edits. In principle, high-affinity asymmetrically split fluorescent proteins solve this problem in C. elegans: the small fragment can quickly and easily be fused to almost any protein of interest, and can be detected wherever the large fragment is expressed and complemented. However, there is currently only one available strain stably expressing the large fragment of a split fluorescent protein, restricting this solution to a single tissue (the germline) in the highly autofluorescent green channel. No available C. elegans lines express unbound large fragments of split red fluorescent proteins, and even state-of-the-art split red fluorescent proteins are dim compared to the canonical split-sfGFP protein. In this study, we engineer a bright, high-affinity new split red fluorophore, split-wrmScarlet. We generate transgenic C. elegans lines to allow easy single-color labeling in muscle or germline cells and dual-color labeling in somatic cells. We also describe a novel expression strategy for the germline, where traditional expression strategies struggle. We validate these strains by targeting split-wrmScarlet to several genes whose products label distinct organelles, and we provide a protocol for easy, cloning-free CRISPR/Cas9 editing. As the collection of split-FP strains for labeling in different tissues or organelles expands, we will post updates at doi.org/10.5281/zenodo.3993663
The Nexus Between Telomere Length and Lymphocyte Count in Seniors Hospitalized With COVID-19
Authors: Benetos Athanase , Lai Tsung-Po , Toupance Simon , Labat Carlos , Verhulst Simon , Gautier Sylvie , Ungeheuer Marie-Noelle , Perret-Guillaume Christine , Levy Daniel , Susser Ezra , Aviv Abraham
Published: February 2021

Profound T-cell lymphopenia is the hallmark of severe coronavirus disease 2019 (COVID-19). T-cell proliferation is telomere length (TL) dependent and telomeres shorten with age. Older COVID-19 patients, we hypothesize, are, therefore, at a higher risk of having TL-dependent lymphopenia. We measured TL by the novel Telomere Shortest Length Assay (TeSLA), and by Southern blotting (SB) of the terminal restriction fragments in peripheral blood mononuclear cells of 17 COVID-19 and 21 non-COVID-19 patients, aged 87 ± 8 (mean ± SD) and 87 ± 9 years, respectively. TeSLA tallies and measures single telomeres, including short telomeres undetected by SB. Such telomeres are relevant to TL-mediated biological processes, including cell viability and senescence. TeSLA yields 2 key metrics: the proportions of telomeres with different lengths (expressed in %) and their mean (TeSLA mTL), (expressed in kb). Lymphocyte count (109/L) was 0.91 ± 0.42 in COVID-19 patients and 1.50 ± 0.50 in non-COVID-19 patients (p < .001). In COVID-19 patients, but not in non-COVID-19 patients, lymphocyte count was inversely correlated with the proportion of telomeres shorter than 2 kb (p = .005) and positively correlated with TeSLA mTL (p = .03). Lymphocyte count was not significantly correlated with SB mTL in either COVID-19 or non-COVID-19 patients. We propose that compromised TL-dependent T-cell proliferative response, driven by short telomere in the TL distribution, contributes to COVID-19 lymphopenia among old adults. We infer that infection with SARS-CoV-2 uncovers the limits of the TL reserves of older persons.

Clinical Trials Registration Number: NCT04325646.
Looking into the performance-based financing black box: evidence from an impact evaluation in the health sector in Cameroon
Authors: de Walque Damien , Robyn Paul Jacob , Saidou Hamadou , Sorgho Gaston , Steenland Maria
Published: February 2021

Performance-based financing (PBF) is a complex health systems intervention aimed at improving the coverage and quality of care. Several studies have shown a positive impact of PBF on health service coverage, often coupled with improvements in quality, but relatively little is known about the mechanisms driving those results. This article presents results of a randomized impact evaluation in Cameroon designed to isolate the role of specific components of the PBF approach with four study groups: (i) PBF with explicit financial incentives linked to results, (ii) direct financing with additional resources available for health providers not linked to performance, (iii) enhanced supervision and monitoring without additional resources and (iv) a control group. Overall, results indicate that, when compared with the pure control group, PBF in Cameroon led to significant increases in utilization for several services (child and maternal vaccinations, use of modern family planning), but not for others like antenatal care visits and facility-based deliveries. In terms of quality, PBF increased the availability of inputs and equipment, qualified health workers, led to a reduction in formal and informal user fees but did not affect the content of care. However, for many positively impacted outcomes, the differences between the PBF group and the group receiving additional financing not linked to performance are not significant, suggesting that additional funding rather than the explicit incentives might be driving improvements. In contrast, the intervention group offering enhanced supervision, coaching and monitoring without additional funding did not experience significant impacts compared to the control group.
‘Seeing’ the Women, Peace and Security agenda: visual (re)productions of WPS in UK government national action plans
Authors: Achilleos-Sarll Columba
Published: February 2021

Examining the visual (re)production of the Women, Peace and Security (WPS) agenda through UK national action plans and annual reports to parliament, this article proposes a new direction for WPS research. The visual politics of WPS, which affects both how the agenda is enacted and how it is encountered, has been largely understudied. To date, WPS scholarship has focused predominantly on linguistic modes of communication, neglecting both the visual aspect of WPS communication and the visual politics of WPS. The article argues that, as a vector of power, visuals matter in the agenda's (re)production, and therefore develops a theoretical and methodological framework to study the visual politics of WPS. In presenting the most comprehensive visual analysis of the WPS agenda to date, this article makes three distinct contributions to the literature. Firstly, it offers a theoretical contribution advancing visuality as a vector of power in the reproduction of WPS. Secondly, it proposes a methodological contribution by developing an analytical framework constructed around a visibility spectrum. Thirdly, it provides an empirical contribution through its focus on the UK as an illustrative case of visual reproduction. The visual analysis reveals four subject-positions placed on a visibility spectrum: the (hypervisible) ‘agential woman-in-conflict’, the (absent presence) of the ‘woman-as-victim’, the (visibility) of the ‘international community’, and the (invisibility) of ‘men and boys’. The analysis demonstrates that rather than challenging global hierarchies of power, these mutually constituted subjects visually reproduce particular gendered, racialized and colonial logics, further stripping the agenda of its transformative potential.
From spawning to first-year recruitment: the fate of juvenile sole growth and survival under future climate conditions in the North Sea
Authors: van de Wolfshaar K E , Barbut L , Lacroix G
Published: February 2021

This study shows the effect of climate change on the growth and survival of early life history stages of common sole (Solea solea) in different nursery areas of the North Sea, by combining a larval transport model with an individual-based growth model (Dynamic Energy Budget) to assess the fate from egg to young of the year at the end of the first growth season. Three scenarios of climate change, inspired by the 2040 Intergovernmental Panel on Climate Change projections, are tested and results are compared to a reference situation representative of current climate conditions. Under climate change scenarios where wind changes, water temperature increases and earlier spawning are considered, the early arrival of fish larvae in their nurseries results in larger young of the year at the end of summer. However, early arrival leads to higher mortality due to initially slow growth in spring. Future climate scenarios result in higher biomass and reduced first-year survival. How this result translates into changes at population level and stock management needs further investigation. Nonetheless, this study illustrates that processes linking life stages are paramount to understand and predict possible consequences of future climate conditions on population dynamics.
Antidepressants and risk of sudden sensorineural hearing loss: a population-based cohort study
Authors: Zhong Pei-Xun , Li I-Hsun , Shih Jui-Hu , Yeh Chin-Bin , Chiang Kuan-Wei , Kao Li-Ting
Published: February 2021

Background

Increasing numbers of animal studies have found that sudden sensorineural hearing loss (SSNHL) is related to the mechanism of serotonergic modulation. However, the relationship between antidepressants and SSNHL is unclear in humans. Therefore, this study aimed to evaluate the association between antidepressant use and risk of SSNHL.

Methods

Data from 218 466 antidepressant users and 1 116 518 nonusers were obtained from the Taiwan Longitudinal Health Insurance Database. We used propensity-score matching (PSM) and inverse-probability treatment weighting (IPTW) to eliminate any bias. Each patient was tracked for 5 years to ascertain whether or not they were diagnosed with SSNHL. Cox proportional-hazard regression analyses were performed to calculate the SSNHL risk.

Results

The adjusted hazard ratio (aHR) of SSNHL for antidepressant users was 1.36 compared with nonusers in the full cohort study. The aHR for antidepressant users was 1.44 and 1.49 compared with the nonusers in the IPTW and PSM cohorts, respectively. All classes of antidepressants consistently increased the SSNHL risk. Additionally, patients receiving four classes of antidepressants were associated with a much higher SSNHL risk (aHR, 2.05) and those receiving one or two classes of antidepressants had a relatively lower SSNHL risk.

Conclusion

Antidepressants increased SSNHL risk, regardless of their class. Furthermore, patients who took a higher number of antidepressant classes showed an increased risk of developing SSNHL than those who took a lower number of antidepressant classes. Therefore, physicians should estimate the risks and benefits of antidepressant use and avoid prescribing antidepressants concurrently.
Neuroendocrine Response to Exogenous Ghrelin Administration, Combined With Alcohol, in Heavy-Drinking Individuals: Findings From a Randomized, Double-Blind, Placebo-Controlled Human Laboratory Study
Authors: Farokhnia Mehdi , Abshire Kelly M , Hammer Aaron , Deschaine Sara L , Saravanakumar Anitha , Cobbina Enoch , You Zhi-Bing , Haass-Koffler Carolina L , Lee Mary R , Akhlaghi Fatemeh , Leggio Lorenzo
Published: February 2021

Background

Accumulating evidence has established a role for the orexigenic hormone ghrelin in alcohol-seeking behaviors. Accordingly, the ghrelin system may represent a potential pharmacotherapeutic target for alcohol use disorder. Ghrelin modulates several neuroendocrine pathways, such as appetitive, metabolic, and stress-related hormones, which are particularly relevant in the context of alcohol use. The goal of the present study was to provide a comprehensive assessment of neuroendocrine response to exogenous ghrelin administration, combined with alcohol, in heavy-drinking individuals.

Methods

This was a randomized, crossover, double-blind, placebo-controlled human laboratory study, which included 2 experimental alcohol administration paradigms: i.v. alcohol self-administration and i.v. alcohol clamp. Each paradigm consisted of 2 counterbalanced sessions of i.v. ghrelin or placebo administration. Repeated blood samples were collected during each session, and peripheral concentrations of the following hormones were measured: leptin, glucagon-like peptide-1, pancreatic polypeptide, gastric inhibitory peptide, insulin, insulin-like growth factor-1, cortisol, prolactin, and aldosterone.

Results

Despite some statistical differences, findings were consistent across the 2 alcohol administration paradigms: i.v. ghrelin, compared to placebo, increased blood concentrations of glucagon-like peptide-1, pancreatic polypeptide, cortisol, and prolactin, both acutely and during the whole session. Lower levels of leptin and higher levels of aldosterone were also found during the ghrelin vs placebo session.

Conclusion

These findings, gathered from a clinically relevant sample of heavy-drinking individuals with alcohol use disorder, provide a deeper insight into the complex interplay between ghrelin and appetitive, metabolic, and stress-related neuroendocrine pathways in the context of alcohol use.
A mathematical model for bleb regulation in zebrafish primordial germ cells
Authors: Dirks Carolin , Striewski Paul , Wirth Benedikt , Aalto Anne , Olguin-Olguin Adan
Published: February 2021

Blebs are cell protrusions generated by local membrane–cortex detachments followed by expansion of the plasma membrane. Blebs are formed by some migrating cells, e.g. primordial germ cells of the zebrafish. While blebs occur randomly at each part of the membrane in unpolarized cells, a polarization process guarantees the occurrence of blebs at a preferential site and thereby facilitates migration toward a specified direction. Little is known about the factors involved in the controlled and directed bleb generation, yet recent studies revealed the influence of an intracellular flow and the stabilizing role of the membrane–cortex linker molecule Ezrin. Based on this information, we develop and analyse a coupled bulk-surface model describing a potential cellular mechanism by which a bleb could be induced at a controlled site. The model rests upon intracellular Darcy flow and a diffusion–advection–reaction system, describing the temporal evolution from a homogeneous to a strongly anisotropic Ezrin distribution. We prove the well-posedness of the mathematical model and show that simulations qualitatively correspond to experimental observations, suggesting that indeed the interaction of an intracellular flow with membrane proteins can be the cause of the Ezrin redistribution accompanying bleb formation.
Genital Abnormalities, Hormonal Contraception, and Human Immunodeficiency Virus Transmission Risk in Rwandan Serodifferent Couples
Authors: Wall Kristin M , Karita Etienne , Nyombayire Julien , Ingabire Rosine , Mukamuyango Jeannine , Parker Rachel , Brill Ilene , Price Matt , Haddad Lisa B , Tichacek Amanda , Hunter Eric , Allen Susan
Published: February 2021

Background

We explored the role of genital abnormalities and hormonal contraception in human immunodeficiency virus (HIV) transmission among heterosexual serodifferent couples in Rwanda.

Methods

From 2002 to 2011, HIV-serodifferent couples who were not using antiretroviral treatment were followed up, and sociodemographic and clinical data were collected, family planning provided, and HIV-negative partners retested. Couples were assessed for genital ulcers; nonulcerative genital sexually transmitted infection (STIs), including gonorrhea, chlamydia, and trichomoniasis; and non-STI vaginal infections, including bacterial vaginosis and candida. Multivariable models evaluated associations between covariates and HIV transmission genetically linked to the index partner.

Results

Among 877 couples in which the man was HIV positive, 37 linked transmissions occurred. Factors associated with women’s HIV acquisition included genital ulceration in the female partner (adjusted hazard ratio, 14.1) and nonulcerative STI in the male partner (8.6). Among 955 couples in which the woman was HIV positive, 46 linked transmissions occurred. Factors associated with HIV acquisition in men included nonulcerative STI in the female partner (adjusted hazard ratio, 4.4), non-STI vaginal dysbiosis (7.1), and genital ulceration in the male partner (2.6). Hormonal contraception use was not associated with HIV transmission or acquisition.

Conclusions

Our findings underscore the need for integrating HIV services with care for genital abnormalities. Barriers (eg, cost of training, demand creation, advocacy, and client education; provider time; and clinic space) to joint HIV/STI testing need to be considered and addressed.
An Efficient Framework for a Third Party Auditor in Cloud Computing Environments
Authors: Mahdavi-Hezavehi S , Alimardani Y , Rahmani R
Published: February 2021

The paper ‘An Efficient Framework for a Third Party Auditor in Cloud Computing Environments’, by S. Mahdavi-Hezavehi, Y. Alimardani and R. Rahmani, published in The Computer Journal, Volume 63, Issue 9, September 2020, explores a new framework for significant cost savings in the cloud.
Expression of the qepA1 gene is induced under antibiotic exposure
Authors: Brandis Gerrit , Gockel Jonas , Garoff Linnéa , Guy Lionel , Hughes Diarmaid
Published: February 2021

Background

The qepA1 gene encodes an efflux pump that reduces susceptibility to ciprofloxacin. Little is known about the regulation of qepA1 expression.

Objectives

To assess the potential role of ciprofloxacin and other antibiotics in the regulation of qepA1 gene expression. To identify the promoter that drives qepA1 expression and other factors involved in expression regulation. To assess whether the identified features are universal among qepA alleles.

Methods

A translational qepA1-yfp fusion under the control of the qepA1 upstream region was cloned into the Escherichia coli chromosome. Expression of the fusion protein was measured in the presence of various antibiotics. Deletions within the upstream region were introduced to identify regions involved in gene expression and regulation. The qepA1 coding sequence and upstream region were compared with all available qepA sequences.

Results

Cellular stress caused by the presence of various antibiotics can induce qepA1 expression. The qepA1 gene is fused to a class I integron and gene expression is driven by the Pc promoter within the integrase gene. A segment within the integron belonging to a truncated dfrB4 gene is essential for the regulation of qepA1 expression. This genetic context is universal among all sequenced qepA alleles.

Conclusions

The fusion of the qepA1 gene to a class I integron has created a novel regulatory unit that enables qepA1 expression to be under the control of antibiotic exposure. This setup mitigates potential negative effects of QepA1 production on bacterial fitness by restricting high-level expression to environmental conditions in which QepA1 is beneficial.