bluuebunny/crossref_metadata_2025 huggingface dataset:
Musical Performance Anxiety (MPA)
Authors: de Figueiredo Rocha Sérgio
Published: March 2020

The musical practice is an extremely complex activity that involves a series of cognitive abilities and functions, among them are hearing, memory, motor coordination, attention, affection, mathematical calculation, and the association of all of these concomitantly, including situations of public exposure. Because of this, musical performance is particularly susceptive to anxiety symptoms. Musical performance anxiety (MPA) is defined as an experience of persistent and distressing apprehension and/or real prejudice of the performance abilities in a public context in an unjustifiable degree given the individual musical aptitude and preparation level. It prevails more commonly on the female gender in a 3:1 proportion and affects about 20% of the professional musicians. In the present chapter, its main etiologies and psychic mechanisms, evaluation instruments, as well as the current therapeutic strategies available will be presented.
Optimal Monochromatic Energy Levels in Dual-Energy Spectral CT Pulmonary Angiography with Low Contrast Medium Dosage
Authors: Han Dong , Shi Weihua , Chen Xiaoxia , Zhou Jieli , Yu Yong , Tian Xin , Chen Jing , Liu Mengting , He Taiping
Published: March 2020

Background: The contrast medium (CM) in CT pulmonary angiography may induce adverse effects to patients, and higher CM is associated with higher rates of contrast-induced-nephropathy and mortality. Reduction of CM dosage through improvement of examination techniques may help reduce the occurrence of CM-induced adverse effects and healthcare costs. Objectives: To determine the optimal monochromatic energy levels in dual-energy spectral CT pulmonary angiography (CTPA) with low contrast dosage. Patients and Methods: Thirty patients with suspected pulmonary embolism (PE) underwent dual-energy spectral CTPA with low radiation and low contrast doses with scanning protocol of GSI-36 with 260 mA, and 25 mL contrast (350 mgI/mL) with 4.0ml/s injection speed. The monochromatic images from 60 - 80 keV (interval 5 keV) were reconstructed using a 50% adaptive statistical iterative reconstruction (50% ASiR) algorithm at 1.25 mm slice thickness. The CT attenuation and standard deviation (SD) values of the main, right, left, right lower and left lower pulmonary arteries and the back muscle at the same level were measured on 60 – 80 keV images, and signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated and analyzed. The subjective image quality was evaluated by two experienced radiologists using a 5-level scoring method independently. Measurements were analyzed using IBM SPSS Statistics for Windows, version 25.0. (Armonk, NY: IBM Corp.). Results: CT attenuation values of the pulmonary arteries decreased with the increase of energy level in five-energy groups, with values greater than 300 HU at 60 keV - 70 keV energies. The 65 keV image had the highest SNR, CNR and lowest SD, with significant differences compared with those of other image sets (P < 0.05). The subjective quality scores for the 65 keV image was judged to be the highest by the two radiologists, but it was not significantly different from 60 keV and 70 keV (all P > 0.05). Conclusion: The 65 keV monochromatic images provided the highest SNR, CNR and subjective scores with the lowest image noise in dual-energy spectral CTPA with low contrast dosage.
Design Considerations to Improve Charpy Instrumented
Strikers
Authors: Vlajic Nicholas , Chijioke Ako , Lucon Enrico
Published: March 2020

Instrumented impact testing allows the applicability of conventional Charpy tests
to be extended toward assessing mechanical properties such as dynamic fracture toughness
and dynamic tensile properties. In this work, we present design considerations for
engineering instrumented strikers for Charpy V-notch impact testing. Specific attention
is given to the mechanical and geometric features, as well as the placement of strain
gauges and corresponding bridge circuits for instrumentation. These design
considerations are intended to make the sensitivity invariant to the location and
distribution of impact forces. The concepts presented in this work were applied to an
actual instrumented striker, which was then statically calibrated. Data from this
calibration indicate that the device has good repeatability, shows a linear response,
and is relatively insensitive to impact location.
Lumbres, vapores y serpientes. Apuntes sobre algunas técnicas de cocción ritual y sus significados entre los antiguos nahuas
Authors: Mazzetto Elena
Published: March 2020

Este artículo está enfocado en el estudio de algunas técnicas de cocción practicadas por los antiguos nahuas en el ciclo de las fiestas del año solar, llamadas “veintenas”. Este tema se estudiará antes de todo desde el punto de vista lingüístico, presentando el análisis de los verbos en náhuatl relacionados con la acción de la cocción –aspecto aún poco documentado por los investigadores–, y vislumbrando su técnica de preparación, a contacto con el aire, el agua, el fuego, etc. Enseguida se analizará el uso de dos técnicas opuestas y complementarias, esto es, el asado y el hervido (preparación al vapor), bajo la forma de presas de cacerías y de tamales realizados con amaranto. El estudio se llevará a cabo analizando tres de las dieciocho veintenas del calendario, buscando el significado simbólico y las implicaciones rituales de este binomio culinario. Para terminar, se aplicarán los resultados del estudio realizado con el vocabulario náhuatl del cocimiento para investigar las técnicas utilizadas para elaborar algunas efigies comestibles de los dioses nahuas, hechas de masa de semillas de amaranto y miel.
Mujeres después de la migración, resiliencia, trabajo y vida doméstica en Isla Grande de Chiloé, Chile 1950-1980
Authors: Saldívar Juan M. , Muñoz Gabriel , Farías Fernanda , Pradines Vladimir
Published: March 2020

Este artículo muestra hallazgos etnográficos e historiográficos sobre la vida doméstica de mujeres chilotas, esposas de migrantes temporeros quienes experimentaron la migración en territorios australes de Patagonia chilena y argentina. Estos desplazamientos migratorios se caracterizan por la distribución de hitos históricos que van desde la década de los 50, con el tizón de la papa; en los 60, etapa crucial provocada por el terremoto; en los 70, con el golpe de estado; y los 80, con la industria salmonera que disminuye considerablemente estos desplazamientos. Las migraciones transnacionales de varones hacia diferentes lugares provocaron jerarquización doméstica, siendo las mujeres un tipo de migrante resiliente, no móvil. La discusión conceptual se centra en tres categorías de análisis: migración resiliente, trabajo doméstico y relaciones de género. El enfoque metodológico es cualitativo, enmarcado en la etnografía multisituada y de contextos interactuados (ECI), como estrategias de reflexión, descripción e interpretación de información.
Atlantia, a new genus of Dendrophylliidae (Cnidaria, Anthozoa, Scleractinia) from the eastern Atlantic
Authors: Capel Kátia C.C. , López Cataixa , Moltó-Martín Irene , Zilberberg Carla , Creed Joel C. , Knapp Ingrid S.S. , Hernández Mariano , Forsman Zac H. , Toonen Robert J. , Kitahara Marcelo V.
Published: March 2020

Atlantia is described as a new genus pertaining to the family Dendrophylliidae (Anthozoa, Scleractinia) based on specimens from Cape Verde, eastern Atlantic. This taxon was first recognized as Enallopsammia micranthus and later described as a new species, Tubastraea caboverdiana, which then changed the status of the genus Tubastraea as native to the Atlantic Ocean. Here, based on morphological and molecular analyses, we compare fresh material of T. caboverdiana to other dendrophylliid genera and describe it as a new genus named Atlantia in order to better accommodate this species. Evolutionary reconstruction based on two mitochondrial and one nuclear marker for 67 dendrophylliids and one poritid species recovered A. caboverdiana as an isolated clade not related to Tubastraea and more closely related to Dendrophyllia cornigera and Leptopsammia pruvoti. Atlantia differs from Tubastraea by having a phaceloid to dendroid growth form with new corallites budding at an acute angle from the theca of a parent corallite. The genus also has normally arranged septa (not Portualès Plan), poorly developed columella, and a shallow-water distribution all supporting the classification as a new genus. Our results corroborate the monophyly of the genus Tubastraea and reiterate the Atlantic non-indigenous status for the genus. In the light of the results presented herein, we recommend an extensive review of shallow-water dendrophylliids from the Eastern Atlantic.
A multiplex centrality metric for complex social networks: sex, social status, and family structure predict multiplex centrality in rhesus macaques
Authors: Beisner Brianne , Braun Niklas , Pósfai Márton , Vandeleest Jessica , D’Souza Raissa , McCowan Brenda
Published: March 2020

Members of a society interact using a variety of social behaviors, giving rise to a multi-faceted and complex social life. For the study of animal behavior, quantifying this complexity is critical for understanding the impact of social life on animals’ health and fitness. Multilayer network approaches, where each interaction type represents a different layer of the social network, have the potential to better capture this complexity than single layer approaches. Calculating individuals’ centrality within a multilayer social network can reveal keystone individuals and more fully characterize social roles. However, existing measures of multilayer centrality do not account for differences in the dynamics and functionality across interaction layers. Here we validate a new method for quantifying multiplex centrality called consensus ranking by applying this method to multiple social groups of a well-studied nonhuman primate, the rhesus macaque. Consensus ranking can suitably handle the complexities of animal social life, such as networks with different properties (sparse vs. dense) and biological meanings (competitive vs. affiliative interactions). We examined whether individuals’ attributes or socio-demographic factors (sex, age, dominance rank and certainty, matriline size, rearing history) were associated with multiplex centrality. Social networks were constructed for five interaction layers (i.e., aggression, status signaling, conflict policing, grooming and huddling) for seven social groups. Consensus ranks were calculated across these five layers and analyzed with respect to individual attributes and socio-demographic factors. Generalized linear mixed models showed that consensus ranking detected known social patterns in rhesus macaques, showing that multiplex centrality was greater in high-ranking males with high certainty of rank and females from the largest families. In addition, consensus ranks also showed that females from very small families and mother-reared (compared to nursery-reared) individuals were more central, showing that consideration of multiple social domains revealed individuals whose social centrality and importance might otherwise have been missed.
Feasibility of anterior pelvic ring fixation alone for treating lateral compression type 1 pelvic fractures with nondisplaced complete sacral fractures: a retrospective study
Authors: Shang Kun , Ke Chao , Fu Ya-Hui , Han Shuang , Wang Peng-Fei , Zhang Bin-Fei , Zhuang Yan , Zhang Kun
Published: March 2020

Purpose

The aim of this study was to evaluate the feasibility of anterior pelvic ring fixation alone for treating lateral compression type 1 (LC-1) fractures with nondisplaced complete sacral fractures.

Methods

Patients with LC-1 type pelvic fractures with nondisplaced complete sacral fractures in the Xi’an Honghui Hospital were screened. Those who underwent surgical treatment for the anterior pelvic ring fractures and conservative treatment for the sacral factures were included in the analysis. The Majeed and Short Form-12 (SF-12) functional scores were used to evaluate these patients.

Results

Of the 123 patients enrolled, 108 (88%) responded to our enquiries regarding the outcome. The mean follow-up period was 18.37 months for the 108 patients who responded. The mean SF-12 functional score was 48.22 ± 9.68. The mean Majeed score was 83.47 ± 9.23, including 52 with excellent, 47 with good, seven with fair, two with poor outcomes. The SF-12 functional and Majeed scores were significantly higher in those aged <45 years or without lower limb injury than in those aged ≥45 years or with lower limb injury (P < 0.05).

Conclusion

Acceptable functional outcomes can be obtained for LC-1 pelvic fractures with nondisplaced complete sacral fractures by using anterior pelvic ring fixation alone.
The complete mitochondrial genome ofFlavoperla biocellataChu, 1929 (Plecoptera: Perlidae) and the phylogenetic analyses of Plecoptera
Authors: Shen Yue , Du Yu-Zhou
Published: March 2020

Of the roughly 400 species of Perlidae in the world, most species are widely distributed in the northern hemisphere, but a few can be found in South Africa and South America. There are only five species in the genusFlavoperlaof the family Perlidae in China. To gain a better understanding of the architecture and evolution of mitochondrial genome inFlavoperla, the entire mitochondrial genome (mitogenome) of a ChineseFlavoperla biocellataChu, 1929 from family Perlidae (Insecta: Plecoptera) was sequenced. The 15,805-bp long mitochondrial genome ofF. biocellatacontained 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs) and a putative control region (CR). The gene arrangement ofF. biocellatawas identical with that of other stoneflies and with the flyDrosophila yakuba. Most PCGs ofF. biocellataused the standard ATN start codons and complete TAN termination codons. Twenty-one of the 22 tRNA genes exhibited cloverleaf secondary structures, but the dihydrouridine (DHU) arm oftrnSer(AGN) was completely reduced. Phylogenetic analyses with both Bayesian inference (BI) and maximum likelihood methods (ML) generated similar topology, both supporting the monophyly of all stonefly families and the infraorder Systellognatha. The phylogenetic analysis based on mitochondrial genomic data from 30 stonefly species recovered a well-supported tree resolving higher-level relationships within Plecoptera. The northern hemisphere suborder Arctoperlaria divided into two groups, Euholognatha and Systellognatha. The southern hemisphere suborder Antarctoperlaria formed two clades: Eustheniidae+Diamphipnoidae and Austroperlidae+ Gripopterygidae; consistent with relationships proposed based on morphology. The final relationships within Plecoptera were recovered as (((Perlidae+(Perlodidae+Chloroperlidae))+(Pteronarcyidae+(Peltoperlidae+Styloperlidae))) +(Taeniopterygidae+(Capniidae+(Nemouridae+Notonemouridae))))+ (Gripopterygoidae+Eusthenioidae).
Characterization and Nutritive Values of Amaranth Seeds
Authors: Singh Akanksha , Punia Darshan
Published: March 2020

Backgrounds: Amaranthus have small lenticular seeds with a curved embryo that surrounds a starchy perisperm and with a seed coat whose color varies among black, brown, yellow and cream-white the present investigation was carried out to analyze the physico-chemical properties and nutritional composition of amaranth.

Methodology: Amaranth grains were procured from the Medicinal Aromatic and Underutilized Plant Section, Department of Genetics and Plant Breeding, College of Agriculture, CCS Haryana Agricultural University, Hisar. Amaranth flour was assessed for its physico-chemical properties and nutrient composition.

Results: Results on physico-chemical properties revealed that bulk density of amaranth flour was 6.06 g/ml, water absorption capacity 9.40 ml/g and fat absorption capacity 58.16%. Swelling capacity of amaranth was 2.54 ml/g. The results of proximate composition revealed that amaranth flour had 10.33% moisture. 14.29% protein, 5.80% fat, 2.84% ash and 4.91% crude fibre. Albumin, globulin, prolamin and glutelin fractions of amaranth were 9.82, 9.50, 1.42 and 1.28 per cent, respectively. The total, soluble and insoluble dietary fibre content of amaranth was 27.34, 9.40 and 17.95%, respectively. Calcium, zinc, iron and potassium contents were 272.03 mg/100 g, 5.81 mg/100 g, 13.76 mg/100 g and 329.87 mg/100 g, respectively.

Conclusion: It can be concluded from the results of present investigation that amaranth is very good source of protein (14.87%), crude fibre (4.91%), ash (2.84%), dietary fibre (27.34%) and minerals specially calcium (272.03 mg/100 g), iron (13.76 mg/100 g) and potassium (329.87 mg/100 g). Amaranth, a pseudo cereal rich in nutrients can be utilized in preparation of traditional products.
Isolation and Molecular Characterisation of Vancomycin Resistant Bacteria Isolated from Selected Well Water in Ula-Ubie Community, Ahoada, Rivers State
Authors: Akani N. P. , Okpokiri M. , Nrior R. R.
Published: March 2020

The resistance of bacteria to vancomycin has made the treatment of some infections more difficult to handle. The aim of this study was to isolate and molecularly characterize vancomycin resistant bacteria in selected well water with a view of determining the level of resistance in the environment. fifty (50) well water samples were collected from ten different stations in Ula-Ubie community, Ahoada, Rivers State for a period of six months (January 2019 to June, 2019). Bacteria diversity was analysed using standard microbiological techniques. In this technique, aliquots of 10-1, 10-2 and 10-3 dilutions were seeded into prepared Nutrient agar and Brain Heart infusion agar (BHI). Microbial loads were enumerated and distinct bacterial colonies were picked and inoculated on freshly prepared nutrient agar. Purification of isolates was done by streaking on freshly prepared nutrient agar plates until isolates were void of mixed culture. The isolates were further characterized using biochemical and molecular methods and preserved in bijou bottles containing 5 ml of 10% (v/v) glycerol. Isolates from the glycerol were subcultured on fresh nutrient agar plates before each use. The vancomycin resistant bacteria were screened using the culture-based screening method. In this method, sterile nutrient medium was supplemented with different concentrations of the vancomycin antibiotics. Inoculation of bacterial isolates on the vancomycin supplemented agar followed before plates were incubated. The ensuing bacterial isolates were characterized using biochemical and molecular methods. Ninetine (19) bacteria isolates were screened for vancomycin and of this numbers, six (6) were positive for vancomycin resistance. The agar rose gel electrophoresis showed the presence of vanA and vanB gene which could be responsible for the resistance to the vancomycin observed in most isolates. The presence of vancomycin resistant genes in these isolates is of public health concern due to the transfer of resistance to other isolates. Standard hygienic practice is therefore recommended in the use of well water.
Prevalence and Socio-demographic Determinants of Stunting among School Age Children (SAC) in Gombe State, Nigeria
Authors: Danjin Mela , Adewoye Solomon O. , Sawyerr Henry O.
Published: March 2020

Background: As one of the key indicators of malnutrition, stunting has been considered to be a very vital proxy for not only chronic nutritional deficit but for long term socioeconomic deprivation among children and the society at large.

Objective: This study was aimed at determining the prevalence of stunting and its association with socio-demographic factors among school children in Gombe state, Nigeria.

Methodology: The study employed a cross sectional survey design to assess school children aged 6 to 15 years in 12 public and 6 private schools from six selected Local Government Areas (LGAs) of the state. Data were collected on a structured pro forma from March to June, 2019. Analysis of the data was done using IBM SPSS version 21 and Chi square statistics was used to compare proportions, while alpha level of significance was set at 0.05.

Results: The mean age of the children was 9.96±2.26 and the overall prevalence of stunting among them was 22.5%. Children in public schools were found to be more stunted (χ2=20.342,   df= 1, P=0.000) and more than twice at risk (OR=2.598, CI=1.699-3.974) of stunting than their counterpart in private schools (27.3% vs. 12.6%). Low academic performance was significantly associated with high prevalence of stunting (28.4% vs. 20.9% & 18.0%) among the subjects (χ2 = 7.443, df = 2, p=0.024). Other factors that were associated with stunting include; class of pupil, age group, LGA, tribe, religion, occupation of father, occupation of mother, SES and level of education of mother.

Conclusion: It is quite evident from the findings of this study that stunting is quite prevalent among school children in Gombe state. Hence, it is recommended that a multi-sectoral approach to addressing the problem be instituted by government and all stakeholders.
Global Value Chain Participation and Current Account Balances in Landlocked African Countries
Authors: Francis Kenfack Geraud , Paul Ningaye , Christophe Kuipou Toukam
Published: March 2020

The objective of this paper is to find out the direction of Global Value Chain Participation (GVCP) that contribute more to the Current Account Balance (CAB) in landlocked African countries from 2000 to 2018. Our specification follows the IMF's External Balance Assessment (EBA) model. The Feasible Generalized Least Square (FGLS) econometric technique is applied on data from three sources: (1) UNCTAD-EORA database for forward and backward participation indicators, (2) World Development Indicator (WDI) data set, for current account balance, foreign direct investment (FDI), population and trade openness and (3) Penn World Tables (PWT) for exchange rates. Results highlight a positive and significant contribution of forward GVCP on CAB in landlocked African countries. The study recommends that landlocked African countries should be active providers of value-added intermediary inputs to other Global Value Chain actors.
Formulation and Evaluation Thermoreversible Gel of Antifungal Agent for Treatment of Vaginal Infection
Authors: Patil Manisha V. , Jadhav Rahul L. , Shaikh Siraj N. , Belhekar Santosh N.
Published: March 2020

Aims: The aim this research work is to formulate and evaluate thermoreversible gel of antifungal agent Clotrimazole for treatment of vaginal infection.

Place and Duration of Study: Department of Biopharmaceutics, Government College of Pharmacy, Karad, Maharashtra, India, between June 2009 and July 2010.

Methodology: Different Formulations of thermoreversible gel of antifungal agent Clotrimazole were prepared by using various concentrations of ethanol, PEG 400, sodium dodecyl sulphate, polycarbophil and pluronic F 127 and pluronic F 68. The gel formulations were subjected for evaluation on the basis of rheological behaviour, mucoadhesive behaviour, in-vitro performance.

Results: The results indicate that Polymers such as polycarbophil, PEG- 400 in various concentrations to prepare formulations were found to release drug for period over 12 hrs. Without getting dislodged. The formulations have satisfactory rheological behavior and their diffusion profile is comparable to the marketed gel formulation. Significant difference was observed in the rheological behavior of formulations. Gel strength, spreadability, mucoadhesive strength of formulation B and C were desirable. Drug diffusion of formulation B and C were 95.2% release after 11 hrs 98.5% release after 11 hrs, respectively which was good as compared to marketed formulation showing drug diffusion of 102.2% after 10 hrs.

Conclusion: On basis of the results we concluded that developed thermoreversible gel of Clotrimazole will be better alternative to conventional dosage form Clotrimazole & will improve patient compliance.
Chemical Warfare Agents
Authors: Costanzi Stefano
Published: March 2020

Chemical weapons are weapons that exploit the toxicity of chemicals to bring about death or harm. The toxic chemicals on which chemical weapons are based are known as chemical warfare agents. This article starts by providing some definitions of chemical weapons and chemical warfare agents as well an overview of key toxicology concepts and some notes on the physicochemical properties of the agents. Subsequently, it illustrates the chemistry, biochemistry, and medical countermeasures of the main classes of chemical warfare agents, namely vesicants, choking agents, blood agents, irritants, nerve agents, and centrally incapacitating agents.
Dairy Substitutes
Authors: Campbell Lydia J. , Euston Stephen R.
Published: March 2020

Dairy product substitutes are growing in market share and product range due to an increased demand for lactose free or vegan products. This article will review the range of dairy substitutes available to the consumer, the ingredients (both dairy and nondairy) that are available to manufacturers, and outline the manufacturing processes used. Particular emphasis is placed on alternative and emerging sources of protein that increasingly are being used to replace dairy proteins in foods. The expanding market for plant‐based dairy substitutes will be explored, and recent changes in the law covering the naming of dairy substitute products will be outlined, including the use of the word milk for nondairy beverages.
Mast cell‐based molecular subtypes and signature associated with clinical outcome in early‐stage lung adenocarcinoma
Authors: Bao Xuanwen , Shi Run , Zhao Tianyu , Wang Yanfang
Published: March 2020

Mast cells are a major component of the immune microenvironment in tumour tissues and modulate tumour progression by releasing pro‐tumorigenic and antitumorigenic molecules. Regarding the impact of mast cells on the outcomes of patients with lung adenocarcinoma (LUAD) patient, several published studies have shown contradictory results. Here, we aimed at elucidating the role of mast cells in early‐stage LUAD. We found that high mast cell abundance was correlated with prolonged survival in early‐stage LUAD patients. The mast cell‐related gene signature and gene mutation data sets were used to stratify early‐stage LUAD patients into two molecular subtypes (subtype 1 and subtype 2). The neural network‐based framework constructed with the mast cell‐related signature showed high accuracy in predicting response to immunotherapy. Importantly, the prognostic mast cell‐related signature predicted the survival probability and the potential relationship between TP53 mutation, c‐MYC activation and mast cell activities. The meta‐analysis confirmed the prognostic value of the mast cell‐related gene signature. In summary, this study might improve our understanding of the role of mast cells in early‐stage LUAD and aid in the development of immunotherapy and personalized treatments for early‐stage LUAD patients.
Specific requirements for translation of biological research into clinical radiation oncology
Authors: Krause Mechthild , Alsner Jan , Linge Annett , Bütof Rebecca , Löck Steffen , Bristow Rob
Published: March 2020

Radiotherapy has been optimized over the last decades not only through technological advances, but also through the translation of biological knowledge into clinical treatment schedules. Optimization of fractionation schedules and/or the introduction of simultaneous combined systemic treatment have significantly improved tumour cure rates in several cancer types. With modern techniques, we are currently able to measure factors of radiation resistance or radiation sensitivity in patient tumours; the definition of new biomarkers is expected to further enable personalized treatments. In this Review article, we overview important translation paths and summarize the quality requirements for preclinical and translational studies that will help to avoid bias in trial results.
Students tell us what good written feedback looks like
Authors: Voelkel Susanne , Varga‐Atkins Tunde , Mello Luciane V.
Published: March 2020

Feedback can be an important element of learning, but only if students engage with it. Students are only likely to engage with feedback that they find useful. This study aimed to identify characteristics of written feedback perceived by students as effective. We used a mixed‐method approach, integrating quantitative and qualitative data that were collected through the analysis of feedback that was identified by students as good, a student questionnaire, as well as interviews and a focus group exploring students’ views on what good feedback looks like. Although the results show that length and composition of ‘good’ feedback can be extremely variable, some common characteristics could be identified, leading to a set of recommendations for staff marking written assessments. According to students, good feedback should be detailed and specific, and it should tell students how they can improve. Students also find it important that feedback is honest and constructive. In addition, positive reinforcement was identified as important by the focus group, although few examples of good written feedback on the assignment contained any direct praise. Surprisingly, feedforward which might help students in other modules did not feature highly in students’ perceptions of good feedback, possibly indicating a focus by students on improving the current assignment rather than on future assignments.
F
rankiales
Authors: Normand Philippe , Fernandez Maria P.
Published: March 2020

Fran.ki.a'les. N.L. fem. n.
Frankia
type genus of the order; suff. ‐
ales
ending to denote an order; N.L. fem. pl. n.
Frankiales
the
Frankia
order.

Actinobacteria / Actinobacteria / Frankiales

A group of slow‐growing aerobic to microaerophilic soil‐inhabiting mesophilic, mostly nitrogen‐fixing, organisms in symbiosis with pioneer plants. Some lineages do not have the ability to establish symbiosis with plants. The position of the order has fluctuated markedly in the various taxonomical treatments that differed on the approach used, but they now consist of the
Frankiaceae
alone placed at the root of the aerobic
Actinobacteria
.
Beam flatness modulation for a flattening filter free photon beam utilizing a novel direct leaf trajectory optimization model
Authors: Potter Nicholas J. , Yan Guanghua , Liu Hongcheng , Alahmad Haitham , Kahler Darren L. , Liu Chihray , Li Jonathan G. , Lu Bo
Published: March 2020

Flattening filter free (FFF) linear accelerators produce a fluence distribution that is forward peaked. Various dosimetric benefits, such as increased dose rate, reduced leakage and out of field dose has led to the growth of FFF technology in the clinic. The literature has suggested the idea of vendors offering dedicated FFF units where the flattening filter (FF) is removed completely and manipulating the beam to deliver conventional flat radiotherapy treatments. This work aims to develop an effective way to deliver modulated flat beam treatments, rather than utilizing a physical FF. This novel optimization model is an extension of the direct leaf trajectory optimization (DLTO) previously developed for volumetric modulated radiation therapy (VMAT) and is capable of accounting for all machine and multileaf collimator (MLC) dynamic delivery constraints, using a combination of linear constraints and a convex objective function. Furthermore, the tongue and groove (T&G) effect was also incorporated directly into our model without introducing nonlinearity to the constraints, nor nonconvexity to the objective function. The overall beam flatness, machine deliverability, and treatment time efficiency were assessed. Regular square fields, including field sizes of 10 × 10 cm2 to 40 × 40 cm2 were analyzed, as well as three clinical fields, and three arbitrary contours with "concave" features. Quantitative flatness was measured for all modulated FFF fields, and the results were comparable or better than their open FF counterparts, with the majority having a quantitative flatness of less than 3.0%. The modulated FFF beams, due to the included efficiency constraint, were able to achieve acceptable delivery time compared to their open FF counterpart. The results indicated that the dose uniformity and flatness for the modulated FFF beams optimized with the DLTO model can successfully match the uniformity and flatness of their conventional FF counterparts, and may even provide further benefit by taking advantage of the unique FFF beam characteristics.
Light‐Coded Digital Crystallinity Patterns Toward Bioinspired 4D Transformation of Shape‐Memory Polymers
Authors: Peng Wenjun , Zhang Guogao , Liu Jian , Nie Shuang , Wu Yi , Deng Shihong , Fang Guangqiang , Zhou Jian , Song Jizhou , Qian Jin , Pan Pengju , Zhao Qian , Xie Tao
Published: March 2020

Spatially heterogeneous distribution of active components is key to the diverse shape‐morphing behaviors of biological species and their associated functions. Artificial morphing materials employing similar strategies have widened the design space for advanced functional devices. Typically, the spatial heterogeneity is introduced during the material synthesis/fabrication step and cannot be altered afterward. An approach that allows spatio‐selective programming of crystallinity in a shape‐memory polymer (SMP) by a digital photothermal effect is reported. The light‐patternable crystallinity affects greatly the shape morphing behavior. Consequently, a pre‐stretched 2D film with spatial heterogeneity in crystallinity can morph with time into designable 3D permanent shapes, achieving the 4D transformation. This approach utilizes a reprocessible thermoplastic SMP (polylactide) and the programming relies on a physical phase transformation (crystallization) instead of chemical heterogeneity. This allows repeated erasing and reprogramming using the same material, suggesting a versatile and sustainable means for manufacturing advanced morphing devices.
All‐Purpose Electrode Design of Flexible Conductive Scaffold toward High‐Performance Li–S Batteries
Authors: He Yusen , Li Mingjun , Zhang Yongguang , Shan Zhenzhen , Zhao Yan , Li Jingde , Liu Guihua , Liang Chunyong , Bakenov Zhumabay , Li Qiang
Published: March 2020

The main obstacles that hinder the development of efficient lithium sulfur (Li–S) batteries are the polysulfide shuttling effect in sulfur cathode and the uncontrollable growth of dendritic Li in the anode. An all‐purpose flexible electrode that can be used both in sulfur cathode and Li metal anode is reported, and its application in wearable and portable storage electronic devices is demonstrated. The flexible electrode consists of a bimetallic CoNi nanoparticle‐embedded porous conductive scaffold with multiple Co/Ni‐N active sites (CoNi@PNCFs). Both experimental and theoretical analysis show that, when used as the cathode, the CoNi and Co/Ni‐N active sites implanted on the porous CoNi@PNCFs significantly promote chemical immobilization toward soluble lithium polysulfides and their rapid conversion into insoluble Li2S, and therefore effectively mitigates the polysulfide shuttling effect. Additionally, a 3D matrix constructed with porous carbonous skeleton and multiple active centers successfully induces homogenous Li growth, realizing a dendrite‐free Li metal anode. A Li–S battery assembled with S/CoNi@PNCFs cathode and Li/CoNi@PNCFs anode exhibits a high reversible specific capacity of 785 mAh g−1 and long cycle performance at 5 C (capacity fading rate of 0.016% over 1500 cycles).
Two‐Dimensional Palladium Diselenide with Strong In‐Plane Optical Anisotropy and High Mobility Grown by Chemical Vapor Deposition
Authors: Gu Yiyi , Cai Hui , Dong Jichen , Yu Yiling , Hoffman Anna N. , Liu Chenze , Oyedele Akinola D. , Lin Yu‐Chuan , Ge Zhuozhi , Puretzky Alexander A. , Duscher Gerd , Chisholm Matthew F. , Rack Philip D. , Rouleau Christopher M. , Gai Zheng , Meng Xiangmin , Ding Feng , Geohegan David B. , Xiao Kai
Published: March 2020

Two‐dimensional (2D) palladium diselenide (PdSe2) has strong interlayer coupling and a puckered pentagonal structure, leading to remarkable layer‐dependent electronic structures and highly anisotropic in‐plane optical and electronic properties. However, the lack of high‐quality, 2D PdSe2 crystals grown by bottom‐up approaches limits the study of their exotic properties and practical applications. In this work, chemical vapor deposition growth of highly crystalline few‐layer (≥2 layers) PdSe2 crystals on various substrates is reported. The high quality of the PdSe2 crystals is confirmed by low‐frequency Raman spectroscopy, scanning transmission electron microscopy, and electrical characterization. In addition, strong in‐plane optical anisotropy is demonstrated via polarized Raman spectroscopy and second‐harmonic generation maps of the PdSe2 flakes. A theoretical model based on kinetic Wulff construction theory and density functional theory calculations is developed and described the observed evolution of “square‐like” shaped PdSe2 crystals into rhombus due to the higher nucleation barriers for stable attachment on the (1,1) and (1,−1) edges, which results in their slower growth rates. Few‐layer PdSe2 field‐effect transistors reveal tunable ambipolar charge carrier conduction with an electron mobility up to ≈294 cm2 V−1 s−1, which is comparable to that of exfoliated PdSe2, indicating the promise of this anisotropic 2D material for electronics.
Defect Engineering for Fuel‐Cell Electrocatalysts
Authors: Li Wei , Wang Dongdong , Zhang Yiqiong , Tao Li , Wang Tehua , Zou Yuqin , Wang Yanyong , Chen Ru , Wang Shuangyin
Published: March 2020

The commercialization of fuel cells, such as proton exchange membrane fuel cells and direct methanol/formic acid fuel cells, is hampered by their poor stability, high cost, fuel crossover, and the sluggish kinetics of platinum (Pt) and Pt‐based electrocatalysts for both the cathodic oxygen reduction reaction (ORR) and the anodic hydrogen oxidation reaction (HOR) or small molecule oxidation reaction (SMOR). Thus far, the exploitation of active and stable electrocatalysts has been the most promising strategy to improve the performance of fuel cells. Accordingly, increasing attention is being devoted to modulating the surface/interface electronic structure of electrocatalysts and optimizing the adsorption energy of intermediate species by defect engineering to enhance their catalytic performance. Defect engineering is introduced in terms of defect definition, classification, characterization, construction, and understanding. Subsequently, the latest advances in defective electrocatalysts for ORR and HOR/SMOR in fuel cells are scientifically and systematically summarized. Furthermore, the structure–activity relationships between defect engineering and electrocatalytic ability are further illustrated by coupling experimental results and theoretical calculations. With a deeper understanding of these complex relationships, the integration of defective electrocatalysts into single fuel‐cell systems is also discussed. Finally, the potential challenges and prospects of defective electrocatalysts are further proposed, covering controllable preparation, in situ characterization, and commercial applications.
Interfacial Engineering of MoO2‐FeP Heterojunction for Highly Efficient Hydrogen Evolution Coupled with Biomass Electrooxidation
Authors: Yang Ganceng , Jiao Yanqing , Yan Haijing , Xie Ying , Wu Aiping , Dong Xue , Guo Dezheng , Tian Chungui , Fu Honggang
Published: March 2020

Simultaneous highly efficient production of hydrogen and conversion of biomass into value‐added products is meaningful but challenging. Herein, a porous nanospindle composed of carbon‐encapsulated MoO2‐FeP heterojunction (MoO2‐FeP@C) is proposed as a robust bifunctional electrocatalyst for hydrogen evolution reaction (HER) and biomass electrooxidation reaction (BEOR). X‐ray photoelectron spectroscopy analysis and theoretical calculations confirm the electron transfer from MoO2 to FeP at the interfaces, where electron accumulation on FeP favors the optimization of H2O and H* absorption energies for HER, whereas hole accumulation on MoO2 is responsible for improving the BEOR activity. Thanks to its interfacial electronic structure, MoO2‐FeP@C exhibits excellent HER activity with an overpotential of 103 mV at 10 mA cm−2 and a Tafel slope of 48 mV dec−1. Meanwhile, when 5‐hydroxymethylfurfural is chosen as the biomass for BEOR, the conversion is almost 100%, and 2,5‐furandicarboxylic acid (FDCA) is obtained with the selectivity of 98.6%. The electrolyzer employing MoO2‐FeP@C for cathodic H2 and anodic FDCA production requires only a low voltage of 1.486 V at 10 mA cm−2 and can be powered by a solar cell (output voltage: 1.45 V). Additionally, other BEORs coupled with HER catalyzed by MoO2‐FeP@C also have excellent catalytic performance, implying their good versatility.
High Spin Hall Conductivity in Large‐Area Type‐II Dirac Semimetal PtTe2
Authors: Xu Hongjun , Wei Jinwu , Zhou Hengan , Feng Jiafeng , Xu Teng , Du Haifeng , He Congli , Huang Yuan , Zhang Junwei , Liu Yizhou , Wu Han‐Chun , Guo Chenyang , Wang Xiao , Guang Yao , Wei Hongxiang , Peng Yong , Jiang Wanjun , Yu Guoqiang , Han Xiufeng
Published: March 2020

Manipulation of magnetization by electric‐current‐induced spin–orbit torque (SOT) is of great importance for spintronic applications because of its merits in energy‐efficient and high‐speed operation. An ideal material for SOT applications should possess high charge‐spin conversion efficiency and high electrical conductivity. Recently, transition metal dichalcogenides (TMDs) emerge as intriguing platforms for SOT study because of their controllability in spin–orbit coupling, conductivity, and energy band topology. Although TMDs show great potentials in SOT applications, the present study is restricted to the mechanically exfoliated samples with small sizes and relatively low conductivities. Here, a manufacturable recipe is developed to fabricate large‐area thin films of PtTe2, a type‐II Dirac semimetal, to study their capability of generating SOT. Large SOT efficiency together with high conductivity results in a giant spin Hall conductivity of PtTe2thin films, which is the largest value among the presently reported TMDs. It is further demonstrated that the SOT from PtTe2layer can switch a perpendicularly magnetized CoTb layer efficiently. This work paves the way for employing PtTe2‐like TMDs for wafer‐scale spintronic device applications.
High External Quantum Efficiency in Fluorescent OLED by Cascade Singlet Harvesting Mechanism
Authors: Lee Kyung Hyung , Lee Jun Yeob
Published: March 2020

The cascade singlet harvesting (CSH) organic light‐emitting diodes (OLEDs) are devised to resolve the low quantum efficiency issue of fluorescent OLEDs by efficient singlet exciton harvesting of the fluorescent emitters. The CSH mechanism is realized by doping a fluorescent emitter in the singlet exciton harvesting matrix consisted of high energy exciplex and low energy exciplex. The high energy exciplex serves as the main component of the emitting layer and the low energy exciplex is a medium harvesting the singlet excitons of the fluorescent emitter. Both exciplexes are thermally activated delayed fluorescence type exciplexes to effectively harvest singlet excitons by reverse intersystem crossing process. The singlet excitons of the low energy exciplex are harvested by the high energy exciplex through Förster energy transfer and then the singlet excitons of the fluorescent emitter are harvested by the low energy exciplex through the second Förster energy transfer process. The CSH mechanism maximizes the singlet exciton formation in the fluorescent emitter, which significantly enhances the external quantum efficiency (EQE) of the fluorescent OLEDs. The optimization of the emitting layer structure provides high EQE of 19.9% in the fluorescent OLEDs compared with 10.4% of a conventional singlet harvesting fluorescent OLED.
Dimeric Thymosin β4 Loaded Nanofibrous Interface Enhanced Regeneration of Muscular Artery in Aging Body through Modulating Perivascular Adipose Stem Cell–Macrophage Interaction
Authors: Chen Wanli , Jia Sansan , Zhang Xinchi , Zhang Siqian , Liu Huan , Yang Xin , Zhang Cun , Wu Wei
Published: March 2020

Regenerating nonthrombotic and compliant artery, especially in the aging body, remains a major surgical challenge, mainly owing to the inadequate knowledge of the major cell sources contributing to arterial regeneration and insufficient bioactivity of delivered peptides in grafts. Ultrathin nanofibrous sheaths stented with biodegrading elastomer present opening channels and reduced material residue, enabling fast cell recruitment and host remodeling, while incorporating peptides offering developmental cues are challenging. In this study, a recombinant human thymosin β4 dimer (DTβ4) that contains two complete Tβ4 molecules is produced. The adult perivascular adipose is found as the dominant source of vascular progenitors which, when stimulated by the DTβ4‐loaded nanofibrous sheath, enables 100% patency rates, near‐complete structural as well as adequate functional regeneration of artery, and effectively ameliorates aging‐induced defective regeneration. As compared with Tβ4, DTβ4 exhibits durable regenerative activity including recruiting more progenitors for endothelial cells and smooth muscle cells, when incorporated into the ultrathin polycaprolactone sheath. Moreover, the DTβ4‐loaded interface promotes smooth muscle cells differentiation, mainly through promoting M2 macrophage polarization and chemokines. Incorporating artificial DTβ4 into ultrathin sheaths of fast degrading vascular grafts creates an effective interface for sufficient muscular remodeling thus offering a robust tool for vessel replacement.
Diversifying cropping systems enhances productivity, stability, and nitrogen use efficiency
Authors: St. Luce Mervin , Lemke Reynald , Gan Yantai , McConkey Brian , May William , Campbell Con , Zentner Robert , Wang Hong , Kroebel Roland , Fernandez Myriam , Brandt Kelsey
Published: March 2020

Long‐term field experiments are useful for determining cropping system productivity, stability, and resource use efficiency. With 12 yr (2004–2015) of data from five cropping systems on a long‐term experiment (> 30 yr) under semiarid conditions in Saskatchewan, Canada, a systems‐approach was used to compare grain and protein yield, stability, nitrogen (N) dynamics, N fertilizer (FUEG,P), and available N use efficiency (NUEG,P) for grain and protein. Annualized grain and protein yields for wheat (Triticum aestivum L.)‐canola (Brassica napus L.)‐wheat‐field pea (Pisum sativum L.; W‐C‐W‐P) were 2244 and 372 kg ha−1, respectively, 14 to 38% and 33 to 66% higher, respectively, than continuous wheat (ContW), summer fallow‐wheat‐wheat‐wheat (F‐W‐W‐W), F‐W‐W, and lentil (Lens culinaris Medik) green manure‐wheat‐wheat (GM‐W‐W). Fallow systems were the most stable, but less productive and well‐adapted to low‐yielding conditions, while GM‐W‐W was the least stable and poorly adapted. The ContW had below‐average stability and was better suited to high‐yielding conditions for grain. The W‐C‐W‐P consistently produced above‐average yields, and was best suited for high‐yielding conditions for grain and protein. The ContW and W‐C‐W‐P had the highest NUEG (26.4 g kg−1) and NUEP (4.1 g kg−1), respectively, with GM‐W‐W having the lowest (18.1 and 2.7 g kg−1); FUE was the reverse of NUE. This long‐term study showed that diversified cropping systems that include pulses can more consistently produce higher grain and protein yields, regardless of growing conditions, than most other systems with lower N fertilizer inputs, thereby potentially reducing the negative environmental consequences associated with N fertilizer application.