bluuebunny/crossref_metadata_2025 huggingface dataset:
Click chemistry-based biopolymeric hydrogels for regenerative medicine
Authors: Li Ya , Wang Xiaonan , Han Yuanyuan , Sun Hung-Yu , Hilborn Jöns , Shi Liyang
Published: October 2020

Click chemistry is not a single specific reaction, but describes ways of generating products which emulate examples in nature. Click reactions occur in one pot, are not disturbed by water, generate minimal and inoffensive byproducts, and are characterized by a high thermodynamic driving force, driving the reaction quickly and irreversibly towards a high yield of a single reaction product. As a result, over the past 15 years it has become a very useful bio-orthogonal method for the preparation of chemical cross-linked biopolymer-based hydrogel, in the presence of e.g. growth factors and live cells, or in-vivo. Biopolymers are renewable and non-toxic, providing a myriad of potential backbone toolboxes for hydrogel design. The goal of this review is to summarize recent advances in the development of click chemistry-based biopolymeric hydrogels, and their applications in regenerative medicine. In particular, various click chemistry approaches, including copper-catalyzed azide-alkyne cycloaddition reactions, copper-free click reactions (e.g. the Diels–Alder reactions, the strain-promoted azide-alkyne cycloaddition reactions, the radical mediated thiol-ene reactions, and the oxime-forming reactions), and pseudo-click reactions (e.g. the thiol-Michael addition reactions and the Schiff base reactions) are highlighted in the first section. In addition, numerous biopolymers, including proteins (e.g. collagen, gelatin, silk, and mucin), polysaccharides (e.g. hyaluronic acid, alginate, dextran, and chitosan) and polynucleotides (e.g. deoxyribonucleic acid), are discussed. Finally, we discuss biopolymeric hydrogels, cross-linked by click chemistry, intended for the regeneration of skin, bone, spinal cord, cartilage, and cornea. This article provides new insights for readers in terms of the design of regenerative medicine, and the use of biopolymeric hydrogels based on click chemistry reactions.
Surface modification of tungsten carbide cobalt by electrical discharge coating with quarry dust powder: an optimisation study
Authors: Yap Ching Yee , Liew Pay Jun , Wang Jingsi
Published: October 2020

In this paper, quarry dust was reused as a coating material on tungsten carbide cobalt (WC–Co) via electrical discharge coating (EDC). Before the EDC process, the quarry dust was mixed well with low smell kerosene oil and surfactant Span 85 to produce a new formulation of dielectric fluid. Response surface methodology was used to investigate the effect of EDC parameters, namely peak current (Ip, 3–5 A) and pulse on time (Ton, 100–300 μs) on the characteristics of the coating surface, including its Vickers micro-hardness, surface roughness and coating layer thickness. Results showed that an increment in Ip and Ton increased the Vickers micro-hardness and coating layer thickness yet decreased the surface finish. The optimum parameters for achieving a hard surface, thick coating layer and low surface roughness are Ip = 4 A and Ton = 341 μs. The established RSM model was in reasonable agreement with the experimental outcomes, and these findings could be useful in the cutting tools, moulds and dies industries for surface modification purposes.
Microstructure, adhesion strength and thermal conductivity of AlN/(Ti, W)/Cu substrate system
Authors: Lin Yingfei , Hao Yangyang , Lu Jianning , Liu Tianlong
Published: October 2020

AlN/(Ti, W)/Cu substrates were successfully fabricated by the combination of magnetron sputtering and electroless copper plating, exhibited layered distribution without obvious defects or delamination. The adhesion film in AlN/Ti/Cu was composed of TiN, Al, and Ti crystallites due to the reaction between the sputtered Ti layer and the AlN substrate, while in AlN/W/Cu was α-W and β-W crystallites with a mixed distribution but a thin W-rich amorphous layer at the interface towards Cu contact. In AlN/TiW/Cu was W-rich TixW1−x and α-Ti with the interlayer distribution. The scratch failure of the AlN/(Ti, W)/Cu substrates included the peeling of the Cu plating layer and adhesion film. The nanoscale hard phase layered combination of the adhesion film in AlN/TiW/Cu exhibited better peeling resistance, resulting in the most prominent adhesion strength among the substrate system. The existence of an amorphous layer in AlN/W/Cu led to the lower thermal conductivity. AlN/TiW/Cu substrate showed good comprehensive properties including adhesion strength and thermal conductivity.
Fast low temperature synthesis of layered perovskite heterojunctions for overall water splitting
Authors: Hofmann Anja , Weiss Morten , Marschall Roland
Published: October 2020

The Ba5Ta4O15-Ba3Ta5O15-BaTa2O6 heterojunction was synthesized for the first time at ambient pressure and mild temperatures without further need of calcination. By systematically adjusting the synthesis parameters, the composition of the composite could be tailored. Detailed Rietveld refinement revealed the highest amount of by-phases for the non-calcined sample with around 12% of Ba3Ta5O15 and 12% of BaTa2O6, respectively. Ba5Ta4O15 represented the main phase for all samples. The non-calcined heterojunction showed the highest activity in photocatalytic hydrogen production with 2360 µmol h−1m−2 corresponding to 1180 µmol h−1 without any co-catalyst. A Rh-Cr2O3 co-catalyst was photodeposited on all samples depending on the surface area for overall water splitting. All samples were active in overall water splitting. This novel synthesis strategy paves the way towards a general low-cost and energy-saving synthesis route to achieve highly crystalline and highly active metal oxide semiconductor photocatalysts.
An experimental investigation on shape memory polymer and metallic stents under bending and radial compression
Authors: Ansari Mehdi , Golzar Mohammad , Baghani Mostafa , Taghavimehr Mehrnoosh , Abbasi Shirsavar Mehran , Yahyavi Mahsa
Published: October 2020

In this paper, shape memory polymers (SMPs) are fabricated by blending Polyurethane (PU) and Polycaprolactone (PCL). A novel method is used to make tubular stents using this blend. The solution coating method is applied to fabricate the SMP stent samples with a non-groove structure. Some metallic commercial stents made of the platinum-chromium alloy are used to compare SMP stents’ the mechanical properties with metal ones. According to the stents’ functionality, two mechanical tests, i.e., radial compression and three-point bending, are conducted in a range of body temperature. According to the mechanical test results, the tubular polymer stent shows a lower strength under the radial forces and a higher strength under the bending forces than to their metal counterparts. However, the mechanical properties of the SMP stents are in the range of metal stents. Thus, the PU/PCL SMP blend can be a promising candidate to be used as the coronary artery stents.
Decolonization, Freemasonry and the rise of ‘homosexuality’ as a public issue in Cameroon: The return of Dr Aujoulat1
Authors: Orock Rogers , Geschiere Peter
Published: October 2020

Relating to academic debates on the emergence of moral panics over homosexuality in several parts of Africa, this article examines rumours on homosexuality as a political issue that connects colonial pasts and postcolonial struggles in Cameroon. We link current struggles over homosexuality to broader debates about the question of Cameroon’s decolonization from France. The article focuses on the figure of Dr Louis Paul Aujoulat, a French colonial official in Cameroon who played a crucial role in the country’s decolonization in the 1950s. Aujoulat died in 1972, but recently, he made a ‘return’ in rumours and public debates in a new role: he is now accused of having ‘sodomized’ the emergent new elite of Cameroon, thus introducing homosexuality; moreover, he is linked to Freemasonry and occult initiation rites. Our aim was to show how a particular decolonization trajectory—very rocky in the case of Cameroon—is related to the present-day moral panic about a supposed proliferation of homosexuality. Freemasonry and its special history on the African continent—notably its role in maintaining the coherence of Françafrique between France and its former colonies—is a severely understudied topic. Its linkages to same-sex practices and illicit enrichment give the Cameroonian case a wider relevance. We argue that the new rumours on Dr Aujoulat define him as a key figure in linking Freemasonry, homosexuality and illicit enrichment to present-day issues of state governance, citizenship and elite misrule in Cameroon.
Current knowledge of SLC6A1-related neurodevelopmental disorders
Authors: Goodspeed Kimberly , Pérez-Palma Eduardo , Iqbal Sumaiya , Cooper Dominique , Scimemi Annalisa , Johannesen Katrine M , Stefanski Arthur , Demarest Scott , Helbig Katherine L , Kang Jingqiong , Shaffo Frances C , Prentice Brandon , Brownstein Catherine A , Lim Byungchan , Helbig Ingo , De Los Reyes Emily , McKnight Dianalee , Crunelli Vincenzo , Campbell Arthur J , Møller Rikke S , Freed Amber , Lal Dennis
Published: October 2020

Advances in gene discovery have identified genetic variants in the solute carrier family 6 member 1 gene as a monogenic cause of neurodevelopmental disorders, including epilepsy with myoclonic atonic seizures, autism spectrum disorder and intellectual disability. The solute carrier family 6 member 1 gene encodes for the GABA transporter protein type 1, which is responsible for the reuptake of the neurotransmitter GABA, the primary inhibitory neurotransmitter in the central nervous system, from the extracellular space. GABAergic inhibition is essential to counterbalance neuronal excitation, and when significantly disrupted, it negatively impacts brain development leading to developmental differences and seizures. Aggregation of patient variants and observed clinical manifestations expand understanding of the genotypic and phenotypic spectrum of this disorder. Here, we assess genetic and phenotypic features in 116 individuals with solute carrier family 6 member 1 variants, the vast majority of which are likely to lead to GABA transporter protein type 1 loss-of-function. The knowledge acquired will guide therapeutic decisions and the development of targeted therapies that selectively enhance transporter function and may improve symptoms. We analysed the longitudinal and cell type-specific expression of solute carrier family 6 member 1 in humans and localization of patient and control missense variants in a novel GABA transporter protein type 1 protein structure model. In this update, we discuss the progress made in understanding and treating solute carrier family 6 member 1-related disorders thus far, through the concerted efforts of clinicians, scientists and family support groups.
Efficacy and Tolerability of Miltefosine in the Treatment of Cutaneous Leishmaniasis
Authors: Ware JeanAnne M , O’Connell Elise M , Brown Thomas , Wetzler Lauren , Talaat Kawsar R , Nutman Thomas B , Nash Theodore E
Published: October 2020

Background

Cutaneous leishmaniasis (CL) is a neglected tropical disease causing an estimated 1 million new cases annually. While antimonial compounds are the standard of care worldwide, they are associated with significant adverse effects. Miltefosine, an oral medication, is United States (US) Food and Drug Administration approved to treat CL caused by Leishmania braziliensis, Leishmania guyanensis, and Leishmania panamensis. Evidence of efficacy in other species and side-effect profiles in CL has been limited.

Methods

Twenty-six patients with CL were treated with miltefosine at the US National Institutes of Health. Species included L. braziliensis (n = 7), L. panamensis (n = 5), Leishmania mexicana (n = 1), Leishmania infantum (n = 3), Leishmania aethiopica (n = 4), Leishmania tropica (n = 2), Leishmania major (n = 1), and unspeciated (n = 3). Demographic and clinic characteristics of the participants, response to treatment, and associated adverse events were analyzed.

Results

Treatment with miltefosine resulted in cure in 77 % (20/26) of cases, with cures among all species. Common adverse events included nausea/vomiting (97%) and lack of appetite (54%). Clinical management or dose reduction was required in a third of cases. Gout occurred in 3 individuals with a prior history of gout. Most laboratory abnormalities, including elevated creatinine and aminotransferases, were mild and normalized after treatment.

Conclusions

Our data suggest that miltefosine has good but imperfect efficacy to a wide variety of Leishmania species. While side effects were common and mostly mild to moderate, some resulted in discontinuation of therapy. Due to oral administration, broad efficacy, and manageable toxicities, miltefosine is a viable alternative treatment option for CL, though cost and lack of local availability may limit its widespread use.
Hercules: Intelligent Coupling of Dual-Mode Flash Memory and Hard Disk Drive
Authors: Cheng Wen , Zou Yuqi , Zeng Lingfang , Wang Yang
Published: October 2020

The write performance of multi-level cell (MLC) is several times slower than single-level cell (SLC); however, the cost per bit of MLC is much lower than SLC. Dual-mode flash (the medium can be partially switched to SLC mode by programming only 1 bit in some cells) can combine SLC and MLC to provide trading density opportunity for performance. In this paper, we present Hercules—a hybrid storage system that couples dual-mode flash memory and hard drive disk (HDD)—based on the content locality principle for high storage performance. The data are divided into two types: the reference data for read operation and the delta data for write operation. The reference data are stored in SLC and the delta data in MLC or HDD in sequential orders. Hercules organizes the metadata for the mapping of the physical locations of the reference blocks and the delta data of the original blocks, intelligently identifies hot/cold data and performs the data migration between MLC and disk for performance improvements. To validate our findings, we implemented Hercules and made evaluation to show that Hercules can effectively improve the data access speed and reduce the response time, compared with the Flashcache storage structure, and in particular, with Hercules, we can achieve 10% performance improvement over the system in absence of hot delta data caching.
Improved Key Recovery Attacks on Simplified Version of K2 Stream Cipher
Authors: Ma Sudong , Guan Jie
Published: October 2020

The K2 stream cipher, designed for 32-bit words, is an ISO/IEC 18033 standard and is listed as a recommended algorithm used by the Japanese government in the CRYPTREC project. The main feature of the K2 algorithm is the use of a dynamic feedback control mechanism between the two linear feedback shift registers, which makes the analysis of the K2 algorithm more difficult. In this paper, for its simplified version algorithm, a key recovery attack is performed by using differential attacks. Firstly, for the unknown key, the same IV is fixed in two chosen IV differential attacks, and we use the input differences and the output differences of the S-box to recover the input of S-box; the internal state values can be uniquely determined by taking intersection of the input of S-box. This technology is used to improve the key recovery attack of seven-round algorithm proposed by Deike Priemuth-Schmid. Secondly, we find the constraint relationship between the keystream equations and the unknown differences by introducing the guess difference bit and eliminate the impossible differences by the constraint relationship. Thus, we expand the key recovery attack from seven to nine rounds. The time complexity of the attack is $\boldsymbol{O} \boldsymbol{(2^{113.93})}$, the data complexity is $\boldsymbol{O}\boldsymbol{(2^{8.71})}$ and the success rate is $\textbf{99.07\%}$.
Assessment of Co-Occurring Substance Use During Opiate Treatment Programs in the United States
Authors: Gormley Mirinda Ann , Blondino Courtney T , Taylor DaShaunda D H , Lowery Elizabeth , Clifford James S , Burkart Benjamin , Graves Whitney C , Prom-Wormley Elizabeth C , Lu Juan
Published: October 2020

The effectiveness of opiate treatment programs (OTPs) can be significantly influenced by co-occurring substance use, yet there are no standardized guidelines for assessing the influence of co-occurring substance use on treatment outcomes. In this review, we aim to provide an overview on the status of the assessment of co-occurring substance use during participation in OTPs in the United States. We searched 4 databases—MEDLINE/PubMed, EMBASE, PsychINFO, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL)—from database inception to November 2018 to select relevant publications on OTPs that assessed participants’ co-occurring substance use. We used a standardized protocol to extract study, intervention, and co-occurring substance use characteristics. Methodological quality was assessed using the Quality in Prognosis Studies tool. Of the 3,219 titles screened, 614 abstracts and 191 full-text original publications were assessed, leaving 85 eligible articles. Co-occurring substance use was most often assessed during opioid treatments using combined (pharmacological and behavioral) (n = 57 studies) and pharmacological (n = 25 studies) interventions. Cocaine, alcohol, marijuana, and benzodiazepines were frequently measured, while amphetamines and tobacco were rarely assessed. Great variation existed between studies in the timing and measurement of co-occurring substance use, as well as definitions for substances and polysubstance/polydrug use. Inconsistencies in the investigation of co-occurring substance use make comparison of results across studies challenging. Standardized measures and consensus on research on co-occurring substance use is needed to produce the evidence required to develop personalized treatment programs for persons using multiple substances and to inform best-practice guidelines for addressing polydrug use during participation in OTPs.
Filling the ranks: the Remplacement Militaire in post-revolutionary France
Authors: Rouanet Louis , Piano Ennio E
Published: October 2020

Many economists have analyzed the efficiency of a volunteered army relative to a conscripted army. However, they have rarely studied the working of real-world alternative, market-based, military institutions where exemptions from military service are traded among the citizens. This paper fills this gap by studying the rise and fall of the Remplacement Militaire in the eighteenth and the nineteenth century France. This system endured for more than three quarters of a century until the French government progressively moved toward universal conscription after 1872. At times of military expansion, the State regulated the replacement market. We argue that the goal of such regulations was to limit the increase in fraud and avoid a deterioration in the quality of the soldiery associated with increases in the price of replacements.
Longitudinal Associations Between Gait, Falls, and Disability in Community-Dwelling Older Adults With Type II Diabetes Mellitus: Findings From The Irish Longitudinal Study on Ageing (TILDA)
Authors: Donoghue Orna A , Leahy Siobhan , Kenny Rose Anne
Published: October 2020

Background

Diabetes is associated with gait deficits, future falls, and disability; however, it is unclear if associations remain after controlling for relevant confounders. This study investigated (i) the effects of type II diabetes on spatiotemporal gait parameters in community-dwelling older adults and (ii) if diabetes status was independently associated with future falls and disability, after controlling for gait and other confounders.

Method

Baseline data were obtained from 2608 community-dwelling adults (≥60 years) participating in The Irish Longitudinal Study on Ageing (TILDA). Diabetes was identified from self-reported doctors’ diagnosis, medications, and glycated hemoglobin levels. Gait characteristics were obtained during single- and dual-task walking using a GAITRite mat (n = 2560). Incident falls and disability were collected over 4 years follow-up (n = 2473). Associations between diabetes status and gait (cross-sectional) and falls and disability (longitudinal) were investigated using regression analysis, adjusting for medications, cardiovascular health, neuropsychological function, and fall-related factors.

Results

Diabetes (prevalence = 9.1%) was cross-sectionally associated with shorter dual-task step length after adjusting for covariates (β = −1.59, 95% CI: −3.10, −0.08, p < .05). Diabetes was independently associated with increased risk of future instrumental activity of daily living (IADL) difficulty in those with no prior difficulty (incidence rate ratio [IRR] = 1.51, 95% CI: 1.08, 2.11, p < .05) although dual-task step length was an important confounder in all disability models. No independent associations between diabetes and falls were observed.

Conclusions

Diabetes was independently associated with shorter dual-task step length and increased risk of future IADL difficulty. Multidimensional interventions addressing poor health and function in those with diabetes may help reduce the risk of gait deficits and future disability.
Spectral induced polarization in anisotropic rocks with electrically conductive inclusions: synthetic model study
Authors: Gurin Grigory , Titov Konstantin , Ilyin Yuri , Fomina Ekaterina
Published: October 2020

Electrically conductive minerals (e.g. graphite, pyrite, chalcopyrite and magnetite) occur in the various geological contexts. They might represent economic resources or serve as indicators of such resources. In addition, they can be sources of contamination of soil and groundwater. Therefore, characterization of rocks containing electrically conductive inclusions is an important task in many sectors of science and economy. We conducted laboratory measurements to study the impact of the shape, composition, size and passivation character of electrically conductive inclusions on the induced polarization (IP) parameters. This paper presents results of time-domain IP measurements performed on 22 synthetic models, which were made of sieved sand mixed with electrically conductive particles. We carried out the IP measurements while varying orientation of the electrical field relative to the long axis of the inclusions. We found that the total chargeability of the models (M) strongly depended on the volumetric content (ξ), shape and characteristic size (l) of the inclusions. It also depended on the angle between the electrical field direction and the orientation of the long axis of the inclusions (α), which made the models anisotropic. Experimental relationships between M, ξ, l and α were found consistent with predictions of the generalized Maxwell–Garnett mixing equation in the tensor form. In contrast to M, the relaxation time (τ) of the studied models was almost independent of $\alpha $. Exceptions were the models with cylindrical electrically conductive particles, which showed a strong relationship between τ and $\ \alpha $. Despite the previous assumptions, no unique relationship between τ and the characteristic length of electrically conductive inclusions was observed. However, for all particle shapes, $\tau $ was proportional to the surface area of the particles. We also studied how passivated areas on the surface of the inclusions modified the spectral IP parameters. We found that passivation of electrically conductive inclusions led to anisotropy of M, while τ remained almost unaffected by the orientation of the polarizing field. Based on the experimental data, we show that the polarization magnitude of electrically conductive inclusions is proportional to the normal component of the electrical current density on their surface. We also show that the relaxation time is proportional to the area of the active surface of the inclusions. The obtained relationships highlight the importance of the interfacial polarization mechanism of the electrically conductive inclusions.
Gravity data inversion for the basement relief delineation through global optimization: a case study from the Aegean Graben System, western Anatolia, Turkey
Authors: Ekinci Yunus Levent , Balkaya Çağlayan , Göktürkler Gökhan , Özyalın Şenol
Published: October 2020

Aegean Graben System is a significant member of the complex geology of western Turkey. The depths to the metamorphic basement reliefs in two major grabens have been reported by many geophysical studies. However, the sediment thicknesses of these graben basins still remain controversial due to the findings differing from each other. Thus, we have inverted the gravity data of the sedimentary cover–metamorphic basement using a stochastic derivative-free vector-based metaheuristic named differential evolution algorithm (DEA). This is the first application of DEA adapted to the basement relief depth problem. Model parametrizations have been achieved by discretizing the basins using a group of juxtaposed vertical blocks. Before the inversion studies, mathematical nature of the inverse problem has been investigated via prediction cost function/error energy maps for some block pairs using a hypothetical basin model. These maps have shown the resolvability characteristic of the block thicknesses on such inversion problem. Parameter tuning studies for the optimum mutation constant/weighting factor have been performed to increase the efficiency of the algorithm. The synthetic data have been successfully inverted via the tuned control parameter and some smoothing operators. Probability density function (PDF) analyses have shown that the best solutions are within the confidence interval limits without uncertainties. In the field data case, long-wavelength anomalies caused by both crustal and deeper effects have been removed from the complete Bouguer anomalies through 2-D finite element method using the element shape functions. Some profiles extracted from the residual gravity anomaly map have been used for the inversion and obtained results have shown that the maximum depths to the metamorphic basement reliefs in the grabens are shallower than the findings of the previous studies. Information obtained from the lithological logs drilled in the grabens has supported our results. Moreover, PDF analyses have indicated the reliability of the obtained solutions without uncertainties.
Molecular Plasticity in Animal Pigmentation: Emerging Processes Underlying Color Changes
Authors: Alvarado Sebastian G
Published: October 2020

Synopsis

Animal coloration has been rigorously studied and has provided morphological implications for fitness with influences over social behavior, predator–prey interactions, and sexual selection. In vertebrates, its study has developed our understanding across diverse fields ranging from behavior to molecular biology. In the search for underlying molecular mechanisms, many have taken advantage of pedigree-based and genome-wide association screens to reveal the genetic architecture responsible for pattern variation that occurs in early development. However, genetic differences do not provide a full picture of the dynamic changes in coloration that are most prevalent across vertebrates at the molecular level. Changes in coloration that occur in adulthood via phenotypic plasticity rely on various social, visual, and dietary cues independent of genetic variation. Here, I will review the contributions of pigment cell biology to animal color changes and recent studies describing their molecular underpinnings and function. In this regard, conserved epigenetic processes such as DNA methylation play a role in lending plasticity to gene regulation as it relates to chromatophore function. Lastly, I will present African cichlids as emerging models for the study of pigmentation and molecular plasticity for animal color changes. I posit that these processes, in a dialog with environmental stimuli, are important regulators of variation and the selective advantages that accompany a change in coloration for vertebrate animals.
Almost Homogeneous Varieties of Albanese Codimension One
Authors: Laurent Bruno
Published: October 2020

We classify almost homogeneous normal varieties of Albanese codimension $1$, defined over an arbitrary field. We prove that such a variety has a unique normal equivariant completion. Over a perfect field, the group scheme of automorphisms of this completion is smooth, except in one case in characteristic $2$, and we determine its (reduced) neutral component.
Key Characteristics of Residual Malaria Transmission in Two Districts in South-Eastern Tanzania—Implications for Improved Control
Authors: Okumu Fredros , Finda Marceline
Published: October 2020

After 2 decades of using insecticide-treated nets (ITNs) and improved case management, malaria burden in the historically-holoendemic Kilombero valley in Tanzania has significantly declined. We review key characteristics of the residual transmission and recommend options for improvement. Transmission has declined by >10-fold since 2000 but remains heterogeneous over small distances. Following the crash of Anopheles gambiae, which coincided with ITN scale-up around 2005-2012, Anopheles funestus now dominates malaria transmission. While most infections still occur indoors, substantial biting happens outdoors and before bed-time. There is widespread resistance to pyrethroids and carbamates; An. funestus being particularly strongly-resistant. In short and medium-term, these challenges could be addressed using high-quality indoor residual spraying with nonpyrethroids, or ITNs incorporating synergists. Supplementary tools, eg, spatial-repellents may expand protection outdoors. However, sustainable control requires resilience-building approaches, particularly improved housing and larval-source management to suppress mosquitoes, stronger health systems guaranteeing case-detection and treatment, greater community-engagement and expanded health education.
The molecular mechanisms of MLKL-dependent and MLKL-independent necrosis
Authors: Li Lu , Tong An , Zhang Qiangsheng , Wei Yuquan , Wei Xiawei
Published: October 2020

Necrosis, a type of unwanted and passive cell demise, usually occurs under the excessive external stress and is considered to be unregulated. However, under some special conditions such as caspase inhibition, necrosis is regulable in a well-orchestrated way. The term ‘regulated necrosis’ has been proposed to describe such programed necrosis. Recently, several forms of necrosis, including necroptosis, pyroptosis, ferroptosis, parthanatos, oxytosis, NETosis, and Na+/K+-ATPase-mediated necrosis, have been identified, and some crucial regulators governing regulated necrosis have also been discovered. Mixed lineage kinase domain-like pseudokinase (MLKL), a core regulator in necroptosis, acts as an executioner in response to ligands of death receptor family. Its activation requires the receptor-interacting protein kinases, RIP1 and RIP3. However, MLKL is only involved in necroptosis, i.e. MLKL is dispensable for necrosis. Therefore, this review is aimed at summarizing the molecular mechanisms of MLKL-dependent and MLKL-independent necrosis.
Duodenal perforation in the pediatric population: two rare cases at a small community hospital
Authors: Hattingh Genevieve , Salas-Parra Ruben D , Nuzhad Afrin , Salvador Joselyn , Farkas Daniel T
Published: October 2020

Duodenal ulcer perforation is very uncommon in the pediatric population; hence, it is usually not considered in the differential diagnosis of acute abdomen in this age group. In our small community hospital, we had two rare cases of perforated peptic ulcer in the pediatric population within a short span of time. A 14-year-old male and a 13-year-old female child presented to the emergency room with acute abdominal pain. No other symptoms were reported and neither had any history of peptic ulcer disease. Abdominal CT showed pneumoperitoneum consistent with perforated hollow viscus. Subsequent exploratory laparotomy indicated perforated duodenal ulcer in both children. These cases illustrate that perforated peptic ulcers should be considered in children presenting with acute abdomen.
A case of an asymptomatic sacrococcygeal teratoma diagnosed in adulthood
Authors: Mourad Ali P , De Robles Marie Shella , O’Toole Sandra , Paver Elizabeth , Winn Robert D
Published: October 2020

Sacrococcygeal teratomas are rare congenital tumours that are even more uncommon when present in adulthood. They are derived from residual stem cells in the presacral space that differentiate into clusters of somatic cell. We present the diagnosis, management and post-operative follow-up in a 37-year-old gentleman referred to our department with an incidental finding of a lobulated presacral cystic mass on computed tomography imaging. Magnetic resonance imaging and fluorodeoxyglucose (FDG)-positron emission tomography (PET) scans were performed to further characterize the lesion. The decision was then made for surgical excision and the specimen along with the coccyx was retrieved en-bloc via a trans-sacral surgical approach. Histopathology of the mass uncovered the presence of squamous, respiratory and prostatic epithelium consistent with the diagnosis of a sacrococcygeal teratoma.
Genome-wide analyses reveal footprints of divergent selection and popping-related traits in CIMMYT’s maize inbred lines
Authors: Li Jing , Li Delin , Espinosa Cristian Zavala , Pastor Viridiana Trejo , Rasheed Awais , Rojas Natalia Palacios , Wang Jiankang , Varela Amalio Santacruz , Carolina de Almeida Silva Natália , Schnable Patrick S , Costich Denise E , Li Huihui
Published: October 2020

Popcorn (Zea mays L. var. Everta) is the most ancient type of cultivated maize. However, there is little known about the genetics of popping-related traits based on genotyping-by-sequencing (GBS) technology. Here, we characterized the phenotypic variation for seven popping-related traits in maize kernels among 526 CIMMYT inbred lines (CMLs). In total, 155 083 high-quality single nucleotide polymorphism (SNP) markers were identified by a GBS approach. Several trait-associated loci were detected by genome-wide association study for color, popping expansion volume, shape, pericarp, flotation index, floury/vitreous, and protein content, explaining a majority of the observed phenotypic variance, and these were validated by a diverse panel comprising 764 tropical landrace accessions. Sixty two of the identified loci were recognized to have undergone selection. On average, there was a 55.27% frequency for alleles that promote popping in CMLs. Our work not only pinpoints previously unknown loci for popping-related traits, but also reveals that many of these loci have undergone selection. Beyond establishing a new benchmark for the genetics of popcorn, our study provides a foundation for gene discovery and breeding. It also presents evidence to investigate the role of a gradual loss of popping ability as a by-product of diversification of culinary uses throughout the evolution of teosinte–to–modern maize.
Endogenous indole-3-acetamide levels contribute to the crosstalk between auxin and abscisic acid, and trigger plant stress responses in Arabidopsis
Authors: Pérez-Alonso Marta-Marina , Ortiz-García Paloma , Moya-Cuevas José , Lehmann Thomas , Sánchez-Parra Beatriz , Björk Robert G , Karim Sazzad , Amirjani Mohammad R , Aronsson Henrik , Wilkinson Mark D , Pollmann Stephan
Published: October 2020

The evolutionary success of plants relies to a large extent on their extraordinary ability to adapt to changes in their environment. These adaptations require that plants balance their growth with their stress responses. Plant hormones are crucial mediators orchestrating the underlying adaptive processes. However, whether and how the growth-related hormone auxin and the stress-related hormones jasmonic acid, salicylic acid, and abscisic acid (ABA) are coordinated remains largely elusive. Here, we analyse the physiological role of AMIDASE 1 (AMI1) in Arabidopsis plant growth and its possible connection to plant adaptations to abiotic stresses. AMI1 contributes to cellular auxin homeostasis by catalysing the conversion of indole-acetamide into the major plant auxin indole-3-acetic acid. Functional impairment of AMI1 increases the plant’s stress status rendering mutant plants more susceptible to abiotic stresses. Transcriptomic analysis of ami1 mutants disclosed the reprogramming of a considerable number of stress-related genes, including jasmonic acid and ABA biosynthesis genes. The ami1 mutants exhibit only moderately repressed growth but an enhanced ABA accumulation, which suggests a role for AMI1 in the crosstalk between auxin and ABA. Altogether, our results suggest that AMI1 is involved in coordinating the trade-off between plant growth and stress responses, balancing auxin and ABA homeostasis.
The dependence of Type Ia Supernovae salt2 light-curve parameters on host galaxy morphology
Authors: Pruzhinskaya M V , Novinskaya A K , Pauna N , Rosnet P
Published: October 2020

Type Ia Supernovae (SNe Ia) are widely used to measure distances in the Universe. Despite the recent progress achieved in SN Ia standardization, the Hubble diagram still shows some remaining intrinsic dispersion. The remaining scatter in supernova luminosity could be due to the environmental effects that are accounted for as mass step correction in the current cosmological analyses. In this work, we compare the local and global colour (U − V), the local star formation rate, and the host stellar mass to the host galaxy morphology. The observed trends suggest that the host galaxy morphology is a relevant parameter to characterize the SN Ia environment. Therefore, we study the influence of host galaxy morphology on light-curve parameters of SNe Ia from the pantheon cosmological supernova sample. We determine the Hubble morphological type of host galaxies for a subsample of 330 SNe Ia. We confirm that the salt2 stretch parameter x1 depends on the host morphology with the p-value ∼10−14. The supernovae with lower stretch value are hosted mainly by elliptical and lenticular galaxies. No correlation for the salt2 colour parameter c is found. We also examine Hubble diagram residuals for supernovae hosted by ‘early-type’ and ‘late-type’ morphological groups of galaxies. The analysis reveals that the mean distance modulus residual in early-type galaxies is smaller than the one in late-type galaxies, which means that early-type galaxies contain brighter supernovae after stretch and colour corrections. However, we do not observe any difference in the residual dispersion for these two morphological groups. The obtained results are in the line with other analyses showing environmental dependence of SN Ia light-curve parameters and luminosity. We confirm the importance of including a host galaxy parameter into the standardization procedure of SNe Ia for further cosmological studies.
Network of thermal cracks in meteorites due to temperature variations: new experimental evidence and implications for asteroid surfaces
Authors: Libourel Guy , Ganino Clément , Delbo Marco , Niezgoda Mathieu , Remy Benjamin , Aranda Lionel , Michel Patrick
Published: October 2020

In recent years, several studies have shown the importance of thermal fracturing of rocks due to temperature variations, on The Earth and Mars. Rock thermal cracking might also be a process at play on the lunar surface. These temperature variations as well as change rates can reach important amplitude on bodies without an atmosphere, in particular on those that reach small perihelion distances such as near-Earth asteroids. On the other hand, the formation, geometry, and extension of cracks on these bodies have not been fully investigated yet. Here, we show results of thermal cracking laboratory experiments on chondrite meteorites, which develop networks of cracks when subjected to rapid temperature cycles with amplitudes similar to those experienced by asteroids with low perihelion distances. The depth of the cracks can reach a few hundred of microns in some hundreds of temperature cycles, in agreement with theoretical studies. We find that dehydration of hydrous minerals enhances the cracking process. The formation of crack networks increases the porosity both at the surface and in the sub-surface of our specimens. We propose that this process could help explaining the recent finding of the very highly porous surfaces of most of the boulders on the asteroids Ryugu and Bennu.
Characteristic scale of star formation – I. Clump formation efficiency on local scales
Authors: Eden D J , Moore T J T , Plume R , Rigby A J , Urquhart J S , Marsh K A , Peñaloza C H , Clark P C , Smith M W L , Tahani K , Ragan S E , Thompson M A , Johnstone D , Parsons H , Rani R
Published: October 2020

We have used the ratio of column densities derived independently from the 850-μm continuum James Clerk Maxwell Telescope Plane Survey and the 13CO/C18O (J = 3 → 2) Heterodyne Inner Milky Way Plane Survey to produce maps of the dense-gas mass fraction (DGMF) in two slices of the Galactic plane centred at ℓ = 30° and 40°. The observed DGMF is a metric for the instantaneous clump formation efficiency (CFE) in the molecular gas. We split the two fields into velocity components corresponding to the spiral arms that cross them, and a two-dimensional power-spectrum analysis of the spiral-arm DGMF maps reveals a break in slope at the approximate size scale of molecular clouds. We interpret this as the characteristic scale of the amplitude of variations in the CFE and a constraint on the dominant mechanism regulating the CFE and, hence, the star formation efficiency in CO-traced clouds.
Line-drag damping of Alfvén waves in radiatively driven winds of magnetic massive stars
Authors: Driessen F A , Kee N D , Sundqvist J O , Owocki S P
Published: October 2020

Line-driven stellar winds from massive (OB) stars are subject to a strong line-deshadowing instability. Recently, spectropolarimetric surveys have collected ample evidence that a subset of Galactic massive stars hosts strong surface magnetic fields. We investigate here the propagation and stability of magnetoradiative waves in such a magnetized, line-driven wind. Our analytic, linear stability analysis includes line-scattering from the stellar radiation, and accounts for both radial and non-radial perturbations. We establish a bridging law for arbitrary perturbation wavelength after which we analyse separately the long- and short-wavelength limits. While long-wavelength radiative and magnetic waves are found to be completely decoupled, a key result is that short-wavelength, radially propagating Alfvén waves couple to the scattered radiation field and are strongly damped due to the line-drag effect. This damping of magnetic waves in a scattering-line-driven flow could have important effects on regulating the non-linear wind dynamics, and so might also have strong influence on observational diagnostics of the wind structure and clumping of magnetic line-driven winds.
magritte, a modern software library for 3D radiative transfer – II. Adaptive ray-tracing, mesh construction, and reduction
Authors: De Ceuster Frederik , Bolte Jan , Homan Ward , Maes Silke , Malfait Jolien , Decin Leen , Yates Jeremy , Boyle Peter , Hetherington James
Published: October 2020

Radiative transfer is a notoriously difficult and computationally demanding problem. Yet, it is an indispensable ingredient in nearly all astrophysical and cosmological simulations. Choosing an appropriate discretization scheme is a crucial part of the simulation, since it not only determines the direct memory cost of the model but also largely determines the computational cost and the achievable accuracy. In this paper, we show how an appropriate choice of directional discretization scheme as well as spatial model mesh can help alleviate the computational cost, while largely retaining the accuracy. First, we discuss the adaptive ray-tracing scheme implemented in our 3D radiative transfer library magritte, that adapts the rays to the spatial mesh and uses a hierarchical directional discretization based on healpix. Second, we demonstrate how the free and open-source software library gmsh can be used to generate high-quality meshes that can be easily tailored for magritte. In particular, we show how the local element size distribution of the mesh can be used to optimize the sampling of both analytically and numerically defined models. Furthermore, we show that when using the output of hydrodynamics simulations as input for a radiative transfer simulation, the number of elements in the input model can often be reduced by an order of magnitude, without significant loss of accuracy in the radiation field. We demonstrate this for two models based on a hierarchical octree mesh resulting from adaptive mesh refinement, as well as two models based on smoothed particle hydrodynamics data.
Using commensurabilities and orbit structure to understand barred galaxy evolution
Authors: Petersen Michael S , Weinberg Martin D , Katz Neal
Published: October 2020

We interpret simulations of secularly evolving disc galaxies through orbit morphology. Using a new algorithm that measures the volume of orbits in real space using a tessellation, we rapidly isolate commensurate (resonant) orbits. We identify phase-space regions occupied by different orbital families. Compared to spectral methods, the tessellation algorithm can identify resonant orbits within a few dynamical periods, crucial for understanding an evolving galaxy model. The flexible methodology accepts arbitrary potentials, enabling detailed descriptions of the orbital families. We apply the machinery to four different potential models, including two barred models, and fully characterize the orbital membership. We identify key differences in the content of orbit families, emphasizing the presence of orbit families indicative of the bar evolutionary state and the shape of the dark matter halo. We use the characterization of orbits to investigate the shortcomings of analytic and self-consistent studies, comparing our findings to the evolutionary epochs in self-consistent barred galaxy simulations. Using insight from our orbit analysis, we present a new observational metric that uses spatial and kinematic information from integral field spectrometers that may reveal signatures of commensurabilities and allow for a differentiation between models.
The TFIIH subunits p44/p62 act as a damage sensor during nucleotide excision repair
Authors: Barnett Jamie T , Kuper Jochen , Koelmel Wolfgang , Kisker Caroline , Kad Neil M
Published: October 2020

Nucleotide excision repair (NER) in eukaryotes is orchestrated by the core form of the general transcription factor TFIIH, containing the helicases XPB, XPD and five ‘structural’ subunits, p62, p44, p34, p52 and p8. Recent cryo-EM structures show that p62 makes extensive contacts with p44 and in part occupies XPD’s DNA binding site. While p44 is known to regulate the helicase activity of XPD during NER, p62 is thought to be purely structural. Here, using helicase and adenosine triphosphatase assays we show that a complex containing p44 and p62 enhances XPD’s affinity for dsDNA 3-fold over p44 alone. Remarkably, the relative affinity is further increased to 60-fold by dsDNA damage. Direct binding studies show this preference derives from p44/p62’s high affinity (20 nM) for damaged ssDNA. Single molecule imaging of p44/p62 complexes without XPD reveals they bind to and randomly diffuse on DNA, however, in the presence of UV-induced DNA lesions these complexes stall. Combined with the analysis of a recent cryo-EM structure, we suggest that p44/p62 acts as a novel DNA-binding entity that enhances damage recognition in TFIIH. This revises our understanding of TFIIH and prompts investigation into the core subunits for an active role during DNA repair and/or transcription.