bluuebunny/crossref_metadata_2025 huggingface dataset:
Male morphotypes of the freshwater prawn Macrobrachium brasiliense (Decapoda: Caridea: Palaemonidae)
Authors: Nogueira Caio Santos , Pantaleão João Alberto Farinelli , Almeida Ariádine Cristine , Costa Rogerio Caetano
Published: February 2020

Some decapod species have intraspecific morphological variations that result in distinct adult morphotypes that influence the population structure, social dominance, and reproduction of the population. Here we investigated whether this differentiation into morphotypes occurs in adult males of Macrobrachium brasiliense, through the analysis of relative growth and morphology. Specimens were collected in the region of Uberlândia, Minas Gerais state, southeastern Brazil. Seven dimensions of each male were measured: carapace length (CL), ischium length, merus length, carpus length, propodus length, dactylus length, and major cheliped length. Principal component analysis, clustering, and discriminant analyses were used to identify possible morphotypes. The analysis of relative growth was employed to estimate the growth patterns of body structures (dependent variables) in relation to the CL (independent variable). Two morphotypes were identified: Mirim, which has less developed chelipeds (23.31 ± 3.08 mm) with fewer spines, and Açu, which has larger chelipeds (41.39 ± 8.14 mm) with many well‐developed spines, especially in the merus. Most morphometric relationships differed significantly (p < .01) between the two morphotypes. The chelipeds were useful characters for the identification of the morphotypes of M. brasiliense, corroborating previous descriptions of the genus. We provide a detailed description of the main macroscopic characteristics that differed between morphotypes, which will enable their identification in future studies. Our results contribute to the knowledge of the population biology of M. brasiliense and should be considered in future investigations, since the presence of these male morphotypes probably influences the reproductive biology and population ecology of the species.
Family caregivers' lived experiences of caring for epidermolysis bullosa patients: A phenomenological study
Authors: Wu Yeh‐Hsun , Sun Fan‐Ko , Lee Pei‐Yu
Published: February 2020

Aims and objectives

To explore the lived experiences of family caregivers of epidermolysis bullosa (EB) patients.

Background

Patients with EB need long‐term care. Their family experiences physical and mental stress while proving that care. However, very little research has explored the family caregivers' actual lived experiences when caring for EB patients.

Design

This is a qualitative research using the phenomenological approach.

Methods

Data were collected with the assistance of the Taiwan Foundation for Rare Disorders (TFRD). Interviews were conducted between 2015 and 2017 with primary family caregivers (n = 10) who had cared for EB patients for at least five years. Data were analysed using Colaizzi's (1978) seven‐step phenomenological method. COREQ reporting guidelines were utilised.

Results

Four themes and eleven subthemes emerged after data analysis: (a) transformation and helplessness: changing expectations and helplessness associated with the rare, unknown disease; (b) mother's responsibility: mothers loving and protecting their children, surviving through adversity and challenges and self‐experiencing a child's pain; (c) physical and mental fatigue experienced by the whole family: physical and mental exhaustion, and unbalanced lives; and (d) adjustment and social support: providing mutual assistance to mitigate adversity, hopeful search for treatments, the importance of patient associations and rare disease foundations, and social assistance requirements.

Conclusion

Family caregivers experience many challenges when caring for EB patients and experience substantial stress and overwhelming burdens. Consequently, they would benefit greatly from various support systems to reduce the burden of caring for EB patients.

Relevance to clinical practice

Healthcare professionals can use the findings from this study to understand the circumstances faced by family caregivers and tailor care and education specifically to support each family's financial, social and household needs, thereby helping them reduce the stress of caring for EB patients.
Methods used to examine technology in relation to the quality of nursing work in acute care: A systematic integrative review
Authors: Redley Bernice , Douglas Tracy , Botti Mari
Published: February 2020

Aims and objectives

To systematically locate, assess and synthesise research to describe methods used to examine technology in relation to the quality of nursing work in acute care. Specific objectives were to (a) describe the types of nursing work examined; (b) describe methods used to examine technology in nursing work; (c) identify outcomes used to evaluate technology in relation to the quality of nursing work; and (d) make recommendations for future research.

Background

New technologies can offer numerous benefits to nurses; however, it is challenging to evaluate health information technologies in relation to the quality of nurses' complex day‐to‐day work.

Design

A systematic integrative review using a five‐step process.

Methods

Five databases were searched using search terms “nurs*,” “workload,” “task,” “time.” Data screening, extraction and interpretation were conducted independently by at least two authors and agreement verified by discussion. Data extraction followed PRISMA guidelines.

Results

Of the 41 studies included, most (87.8%, n = 36) examined physical dimensions of nursing work; 31.7% (n = 13) organisational dimensions; 17.1% (n = 8) cognitive dimensions; and only 12.2% (n = 5) emotional dimensions. More than half (58.5%, n = 24) examined only one dimension; one captured all four dimensions. Most frequently examined technologies were electronic medical/health records (36.5%) and electronic medication management (19.5%). Direct observation (58.8%, n = 28) and multiple methods (19.5%, n = 8) were the most common methods; nurse tasks, frequency, duration and time distribution were variables most often measured.

Conclusions

Examinations of technology in nursing work often failed to capture the multiple dimensions of this work nor did they recognise the complexity of day‐to‐day nursing work in acute care. There is a paucity of literature to inform how and what technology should be measured in relation to the quality of nursing care.

Relevance to clinical practice

The outcomes inform useful research methods to comprehensively examine technology to enhance the quality of complex nursing work.
Huge broad ligament leiomyoma with cystic degeneration: A diagnostic and surgical challenge
Authors: Jha Sangam , Singh Anamika , Singh Samanta , Murmu Suhagini
Published: February 2020

Broad ligament is the common extrauterine site for fibroid. We present a case of huge broad ligament fibroid with cystic degeneration. Patient presented with abdominal swelling and mild pain abdomen. On abdominal examination, a large tense cystic mass of 34 weeks gravid uterus size arising from pelvis was noted. Cervix was pulled up and all fornices were full with mass on pelvic examination. Ultrasound suggested adnexal mass as ovaries were not seen. Contrast‐enhanced computed tomography abdomen too reported adnexal mass likely of ovarian origin. On laparotomy, 6 L of straw color fluid drained from the mass which was seen arising from left broad ligament, bilateral ovaries were separate from the mass and appeared healthy. Enucleation of mass was done to ease the hysterectomy and careful evaluation of ureteric course was done throughout the surgery to avoid its injury. Total hysterectomy with bilateral salpingo‐opherectomy and pelvic lymphadenectomy was performed. This case is being reported for its rare incidence, diagnostic dilemma and surgical challenge.
Associations among echocardiography, cardiac biomarkers, insulin metabolism, morphology, and inflammation in cats with asymptomatic hypertrophic cardiomyopathy
Authors: van Hoek Ingrid , Hodgkiss‐Geere Hannah , Bode Elizabeth F. , Hamilton‐Elliott Julie , Mõtsküla Paul , Palermo Valentina , Pereira Yolanda M. , Culshaw Geoff J. , Ivanova Anna , Dukes‐McEwan Jo
Published: February 2020

Background

Insulin, insulin‐like growth factor‐1 (IGF‐1), and inflammation possibly are involved in cats with asymptomatic hypertrophic cardiomyopathy (aHCM).

Objectives

To evaluate echocardiography, morphology, cardiac and inflammatory markers, insulin and IGF‐1 in cats with aHCM.

Animals

Fifty‐one client‐owned cats with aHCM.

Methods

Observational descriptive study. Variables (body weight [BW], body condition score [BCS], echocardiography, and serum concentrations of N‐terminal pro‐B‐type natriuretic peptide [NT‐proBNP], ultra‐sensitive troponin‐I [c‐TnI], serum amyloid A [SAA], insulin, glucose and IGF‐1) were evaluated for significant increases above echocardiography cutoff values and laboratory reference ranges, associations and effect of left atrial (LA) remodeling and generalized hypertrophy.

Results

Cats with aHCM had BCS ≥6/9 (P = .01) and insulin (P < .001), NT‐proBNP (P = .001) and cTn‐I (P < .001) above laboratory reference ranges. Associations were present between NT‐proBNP and maximum end‐diastolic interventricular septum thickness (IVSd; ρ = .32; P = .05), maximum end‐diastolic left ventricular free wall thickness;(ρ = .41; P = .01), LA/Aorta (ρ = .52; P = .001) and LA diameter (LA‐max; ρ = .32; P = .05); c‐TnI and LA/Aorta (ρ = .49; P = .003) and LA‐max (ρ = .28; P = .05); and SAA and number of IVSd regions ≥6 mm thickness (ρ = .28; P = .05). Body weight and BCS were associated with IGF‐1 (r = 0.44; P = .001), and insulin (ρ = .33; P = .02), glucose (ρ = .29; P = .04) and IGF‐1 (ρ = .32; P = .02), respectively. Concentrations of NT‐proBNP (P = .02) and c‐TnI (P = .01), and SAA (P = .02), were higher in cats with LA remodeling, and generalized hypertrophy, respectively.

Conclusions and clinical importance

Results suggest potential implications of insulin, IGF‐1, and inflammation in cats with aHCM, but it remains to be confirmed whether these findings represent a physiological process or a part of the pathogenesis and development of disease.
Foreign Language Learning Characteristics of Deaf and Severely Hard‐of‐Hearing Students
Authors: CSIZÉR KATA , KONTRA EDIT H.
Published: February 2020

The aim of this study was to investigate deaf and severely hard‐of‐hearing students’ foreign language learning characteristics. In order to provide a better understanding of the challenges this group of learners face, a mixed methods study was designed including a questionnaire survey to provide generalizable results for our context and an interview study to get a deeper understanding of the issue from the insiders’ perspective as well. Data was collected in three European countries with piloted and barrier‐free instruments. In order to investigate their foreign language learning processes, deaf and severely hard‐of‐hearing students’ motivation, beliefs, and strategies were measured and analyzed. Our results indicate that deaf and severely hard‐of‐hearing students’ foreign language learning experiences are fraught with challenges and setbacks despite their motivation and eagerness to learn foreign languages. To overcome these difficulties motivating and effective learning environments have to be created where the use of the national sign language contributes to the efficiency of teaching. Furthermore, teaching should include the presentation of effective learning strategies as well as the introduction of autonomous ways of learning.
Trait‐dependency of trophic interactions in zooplankton food webs
Authors: Vincent Florian , Bertolo Andrea , Lacroix Gérard , Mouchet Maud , Edeline Eric
Published: February 2020

Anthropogenic change in the abundance or identity of dominant top predators may induce reorganizations in whole food webs. Predicting these reorganizations requires identifying the biological rules that govern trophic niches. However, we still lack a detailed understanding of the respective contributions of body size, behaviour (e.g. match between predator hunting mode and prey antipredator strategy), phylogeny and/or ontogeny in determining both the presence and strength of trophic interactions. Here, we address this question by measuring zooplankton numerical response to fish predators in lake enclosures. We compared the fit to zooplankton count data of models grouping zooplankters based either on 1) body sizes, 2) antipredator behaviour, 3) body size combined with antipredator behaviour or on 4) phylogeny combined with ontogeny (i.e. different life stages of copepods). Body size was a better predictor of zooplankton numerical response to fish than antipredator behaviour, but combining body size and behaviour provided even better predictions. Models based on phylogeny combined with ontogeny clearly outperformed those based on other zooplankton grouping rules, except when phylogeny was poorly resolved. Removing ontogenetic information plagued the predictive power of the highly‐resolved (genus‐level) phylogenetic grouping but not of medium‐resolved or poorly‐resolved phylogenetic grouping. Our results support the recent use of phylogeny as a superior surrogate for traits controlling trophic niches, and further highlight the added value of combining phylogeny with ontogenetic traits. Further improvements in our mechanistic understanding of how trophic networks are shaped are bound to uncovering the trophic traits captured by phylogeny and ontogeny, but that currently remain hidden to us.
Electrocardiographic morphology during left bundle branch area pacing: Characteristics, underlying mechanisms, and clinical implications
Authors: Gao Ming‐Yang , Tian Ying , Shi Liang , Wang Yan‐Jiang , Xie Bo‐Qia , Qi Jie , Zeng Li‐Jun , Li Xue‐Xun , Yang Xin‐Chun , Liu Xing‐Peng
Published: February 2020

Aims

In this study, we investigated the characteristics and underlying mechanisms of the electrocardiographic (ECG) morphology during left bundle branch area pacing (LBBAP), which have not been systematically described.

Methods

Patients with indications for permanent cardiac pacing underwent LBBAP attempts. The ECGs of patients with confirmed left bundle branch (LBB) capture were compared with those of individuals with right bundle branch block (RBBB) on 12‐lead ECG. Intracardiac electrograms recorded during implantation were analyzed in all patients who underwent pacing.

Results

LBBAP was successfully achieved in 87.5% (56/64) of patients. The QRS morphologies in lead V1 during LBBAP, which typically demonstrated Qr (60.7%), qR (19.6%), rSR’ (7.1%), or QS (12.5%) patterns, differed from those of native RBBB, which featured rsR’ (57.5%), M shape (23.7%), or monophasic R patterns (18.7%). The terminal R' wave duration in lead V1 was significantly shorter during LBBAP than during native RBBB (51 ± 12 ms vs 85 ± 19 ms, p < 0.001). LBB potentials were recorded in 66.1% (37/56) of the LBBAP patients. No significant differences in ECG characteristics were found between LBBAP with and without recorded LBB potentials. The presence of bundle branch block during LBBAP significantly prolonged QRS duration, R wave peak time, and terminal R’ wave duration in lead V1.

Conclusion

LBBAP‐ECG patterns are characterized by a shorter terminal R’ wave duration in lead V1 compared with that of native RBBB configurations. Bundle branch conduction integrity has an impact on ECG characteristics during LBBAP.
Outcomes of allogenic hematopoietic cell transplantation for childhood chronic myeloid leukemia: Single‐center experience
Authors: Hafez Hanafy A. , Abdallah Amr , Hammad Mahmoud , Hamdy Nayera , Yassin Dina , Salem Sherine , Hassanain Omayma , Elhalaby Lama , Elhaddad Alaa
Published: February 2020

Background/objectives

Despite the apparent efficacy and favorable toxicity profile of TKIs, allogeneic SCT remains the only curative treatment for CML especially in younger patients, but TRM should be considered. We evaluated the clinical outcomes of pediatric CML patients who had SCT in our center.

Methods

This retrospective study included children with CML, who received an allogeneic SCT at Children Cancer Hospital Egypt, 57357, from 2007 to 2017. All patients received myeloablative conditioning chemotherapy containing busulfan/cyclophosphamide followed by stem cell infusion from MRD.

Results

From 121 patients diagnosed with CML, 43 had available MRD and subjected to HSCT while 78 patients continued TKI therapy. The median time to transplant from diagnosis was 13 months. At initial diagnosis, there were 39 patients in CP and 4 had blastic crises. Bone marrow harvest was the stem cell source in 32 patients, while 11 cases received mobilized peripheral blood stem cells with average stem cell dose of 4.45 × 106/kg. The probabilities of overall survival and event‐free survival at 5 years were 97.4% and 79.8%, respectively. TRM at 100 days and TRM at 1‐year post‐transplant were 0%. The incidence of chronic GVHD was significantly higher in peripheral blood than bone marrow stem cell source (P = .004).

Conclusion

Considering the excellent survival rates and very low TRM, HSCT is still a valid option for pediatric patients with newly diagnosed CML with best using marrow stem cell source to avoid a significant risk of cGVHD and its related complications.
Grenander functionals and Cauchy's formula
Authors: Groeneboom Piet
Published: February 2020

Let be the nonparametric maximum likelihood estimator of a decreasing density. Grenander characterized this as the left‐continuous slope of the least concave majorant of the empirical distribution function. For a sample from the uniform distribution, the asymptotic distribution of the L2‐distance of the Grenander estimator to the uniform density was derived in an article by Groeneboom and Pyke by using a representation of the Grenander estimator in terms of conditioned Poisson and gamma random variables. This representation was also used in an article by Groeneboom and Lopuhaä to prove a central limit result of Sparre Andersen on the number of jumps of the Grenander estimator. Here we extend this to the proof of the main result on the L2‐distance of the Grenander estimator to the uniform density and also prove a similar asymptotic normality results for the entropy functional. Cauchy's formula and saddle point methods are the main tools in our development.
The Norm among the Exceptional? Experiences of Latino Students in Elite Institutions
Authors: Pan Yung‐Yi Diana , Reyes Daisy Verduzco
Published: February 2020

This article examines Latino students’ experiences within two elite educational contexts: an elite liberal arts college and an elite law school. Drawing on combined data of 42 in‐depth interviews, we interrogate how elite institutional spaces reify and shape panethnic identities. In the face of marginalization in predominantly white, elite spaces Latino students strategically search for new community and comfort, which in turn influence how they perceive their identities, encouraging a broadening of boundaries to include both panethnic and minority alliances. By documenting the experiences of Latino students in two stages of the educational pipeline, we show how elite institutions influence identity talk lead students to cultivate a sense of shared fate with other Latino‐origin individuals and at times, people of color in general.
Detection of an HLA‐A*02 variant, HLA‐A*02:346, in a Taiwanese individual
Authors: Yang Kuo‐Liang , Li Chi‐Cheng , Lin Py‐Yu
Published: February 2020

One nucleotide replacement at codon 90 of HLA‐A*02:01:01:01 results in a novel allele, HLA‐A*02:346.
Risk as Challenge: A Dual System Stochastic Model for Binary Choice Behavior
Authors: Shye Samuel , Haber Ido
Published: February 2020

Challenge Theory (CT) is a new approach to decision under risk that departs significantly from expected utility and is based firmly on psychological, rather than economic, assumptions. The paper demonstrates that a purely cognitive-psychological paradigm for decision under risk can yield excellent predictions, comparable to those attained by more complex economic or psychological models that remain attached to conventional economic constructs and assumptions. The study presents a new model for predicting the popularity of choices made in binary risk problems.A CT-based regression model is tested on data gathered from 126 respondents who indicated their preferences with respect to 44 choice problems. Results support CT's central hypothesis, strongly associating between the Challenge Index (CI) attributable to every binary risk problem, and the observed popularity of the bold prospect in that problem (with r=-0.92 and r=-0.93 for gains and for losses, respectively). The novelty of the CT perspective as a new paradigm is illuminated by its simple, single-index (CI) representation of psychological effects proposed by Prospect Theory for describing choice behavior (certainty effect, reflection effect, overweighting small probabilities and loss aversion).
Degradation of the Incretin Hormone Glucagon-Like Peptide-1 (GLP-1) by Enterococcus faecalis Metalloprotease GelE
Authors: LeValley Stephanie L. , Tomaro-Duchesneau Catherine , Britton Robert A.
Published: February 2020

Humans have a complex and interconnected relationship with their gastrointestinal microbiomes, yet our interest in the microbiome tends to focus on overt pathogenic or probiotic activities, leaving the roles that commensal species may have on host physiology and metabolic processes largely unexplored. Commensal organisms in the microbiome produce and secrete many factors that have an opportunity to interact with the gastrointestinal tract and host biology. Here, we show that a secreted protease from
E. faecalis
, GelE, is able to degrade the gastrointestinal hormone GLP-1, which is responsible for regulating glucose homeostasis and appetite in the body. The disruption of natural GLP-1 signaling by GelE may have significant consequences for maintaining healthy blood glucose levels and in the development of metabolic disease. Furthermore, this work deepens our understanding of specific host-microbiome interactions.
Morphology and Transcriptome Analysis of Nosema bombycis Sporoplasm and Insights into the Initial Infection of Microsporidia
Authors: He Qiang , Luo Jian , Xu Jin-Zhi , Wang Chun-xia , Meng Xian-zhi , Pan Guo-Qing , Li Tian , Zhou Ze-Yang
Published: February 2020

Once awoken from dormancy, the cellular matter of microsporidia is delivered directly into the host cell cytoplasm through the polar tube. This means that the microsporidia are difficult to study biologically in their active state without a contaminating signal from the host cell. Sporoplasm is a cell type of microsporidiain vitro, but relatively little attention has been paid to the sporoplasm in the past 150 years due to a lack of an effective separation method.Nosema bombycis, the first reported microsporidium, is a type of obligate intracellular parasite that infects silkworms and can be induced to germinate in alkaline solutionin vitro. We successfully separated theN. bombycissporoplasmin vitro, and the morphological and structural characteristics were investigated. These results provide important insight into the biology and pathogenesis of microsporidia and potentially provide a possible strategy for genetic manipulation of microsporidia targeting the sporoplasm.
Loss of voltage-gated proton channel Hv1 leads to diet-induced obesity in mice
Authors: Pang Huimin , Li Jinwen , Du Hongyan , Gao Yingtang , Lv Jili , Liu Yanxia , Li Shu Jie
Published: February 2020

Objective

The voltage-gated proton channel Hv1 has been proposed to mediate NADPH oxidase (NOX) function by regulating intracellular pH during respiratory bursts. In our previous work, we showed that Hv1 is expressed in pancreatic β cells and positively regulates insulin secretion. Here, we investigated the role of Hv1 in adipose tissue differentiation, metabolic homeostasis and insulin sensitivity using Hv1 knockout (KO) mice.

Design

Mice with genetic deletion of Hv1 are treated with high-fat diet (HFD) similar to wild-type (WT) mice. Body weight gain, adiposity, insulin sensitivity and gene expressions in both adipose tissue and liver were analyzed.

Results

Mice with genetic deletion of Hv1 display overt obesity with higher body weight gain and accumulation of adipose tissue compared with similarly HFD-treated WT. Hv1-deficient mice develop more glucose intolerance than WT, but no significant difference in insulin resistance, after fed with HFD. Deficiency of Hv1 results in a remarkable increase in epididymal adipocyte weight and size, while the gene expressions of proinflammatory factors and cytokines are obviously enhanced in the HFD-fed mice. Furthermore, the gene expression of Hv1 is increased in the HFD-fed mice, which is accompanied by the increase of NOX2 and NOX4. In addition, there is more severely diet-induced steatosis and inflammation in liver in KO mice.

Conclusion

Our data demonstrated that lacking of Hv1 results in diet-induced obesity in mice through inflammation and hepatic steatosis. This study suggested that Hv1 acts as a positive regulator of metabolic homeostasis and a potential target for antiobesity drugs in therapy and may serve as an adaptive mechanism in cooperating with NOX to mediate reactive oxygen species for adipogenesis and insulin sensitivity.
Contraction fatigability during interleaved neuromuscular electrical stimulation of the ankle dorsiflexors does not depend on contraction amplitude
Authors: Ainsley Emily N. , Barss Trevor S. , Collins David F.
Published: February 2020

Interleaved neuromuscular electrical stimulation (iNMES) involves alternating stimulus pulses between the tibialis anterior muscle and common peroneal nerve. The current investigation aimed to characterize the relationship between contraction amplitude, motor unit (MU) “overlap”, and contraction fatigability during iNMES. It was hypothesized that as iNMES generates progressively larger contractions, more MUs would be recruited from both sites (i.e., more MU overlap), resulting in more fatigability for larger than smaller contractions. Fourteen participants completed 3 sessions. Fatigability was assessed as the decline in torque over 180 contractions (0.3 s “on”, 0.7 s “off”) when iNMES was delivered to produce initial contractions of ∼5%, 15%, or 30% of a maximal voluntary contraction. Although MU overlap increased significantly with contraction amplitude, the relative (percent) decline in torque was not different between the contraction amplitudes and torque declined on average by 23%. Contraction fatigability was not significantly correlated with either MU overlap or initial contraction amplitude. In conclusion, iNMES can produce fatigue-resistant contractions across a functionally-meaningful range of contraction amplitudes for rehabilitation.

Novelty Interleaved neuromuscular electrical stimulation progressively recruits MUs as contraction amplitude increases. However, the relative amount of fatigability of recruited MUs was not different as contraction amplitude increased. This suggests iNMES can be used effectively to produce fatigue-resistant and functionally meaningful contractions.
Metal-free oxidative C(sp3)–H functionalization: a facile route to quinoline formaldehydes from methyl-azaheteroarenes
Authors: Weng Wei-Zhao , Guo Jiang-Shan , Liu Kai-Xuan , Shao Tian-Qi , Song Li-Qun , Zhu Yan-Ping , Sun Yuan-Yuan , Meng Qing-Guo
Published: February 2020

A facile protocol for the synthesis of quinoline formaldehydes via direct oxidative C–H bonds functionalization of methyl-azaheteroarenes in the presence of I2–DMSO has been described. This method is metal-free and easy to operate. This reaction provided a convenient route for the preparation of a range of important quinoline formaldehydes.
Nonlinear Vibration and Stability Analysis of Thermally Postbuckled Double-Layered Graphene Sheet under 1:1 and 3:1 Internal Resonance
Authors: Varzandian G. A. , Ziaee S. , Farid M. , Niknejad A.
Published: February 2020

In the present research, vibration behavior is presented for a thermally postbuckled double layered graphene sheet (DLGS). The DLGS is modeled as a nonlocal orthotropic plate and contains small-scale effects. The formulations are based on Kirchhoff’s plate theory and nonlinearity of von Karman type is considered in strain–displacement relations. The thermal effects, van der Waals forces between layers and chirality are also included, and some of the material properties are assumed to be temperature-dependent. A coupled system of equations is derived and a new semi-analytical solution is obtained using multiple time-scale methods. The effects of variation of small-scale parameter on the natural frequencies, deflections and response curve of DLGS are analyzed, and the numerical results are obtained from the nonlocal plate model; also, molecular dynamics (MD) simulations are used to investigate different vibration behaviors of DLGS and calibration of the small-scale coefficient. Numerical results are compared with those of similar researches. Effects of various parameters on the postbuckled vibration of DLGS in thermal environments such as scale parameter, environmental damping, length and thermal load are presented. The stability and occurrence of internal resonance between vibration modes around a stable buckled configuration are investigated.
Improvement of Discrete-Mechanics-Type Time Integration Schemes by Utilizing Balance Relations in Integral form Together with Picard-Type Iterations
Authors: Oborin Evgenii , Irschik Hans
Published: February 2020

The search for efficient explicit time integration schemes is a relevant topic in the current literature on dynamic mechanical systems. In this paper, we describe a strategy of utilizing the balance relations of mechanics in their integral form, so-called general laws of balance, where the time-evolution of the integrands is approximated by established computational techniques of the discrete-mechanics-type. In a Picard-type iteration, the outcomes are used for repeating the procedure several times, leading to an increased accuracy. The advantages of the present explicit approach are discussed in the context of linear and nonlinear motions of the mathematical pendulum. We utilize the modern symbolic procedures to obtain the time integration formulae and compare the results of our methods with exact solutions and with the results of higher-order implicit methods and also with a recent explicit formulation from the literature.
Robert Jameson's transition from Neptunism to Plutonism as reflected in his lectures at Edinburgh University, 1820–33
Authors: Stone Philip
Published: February 2020

Robert Jameson is generally remembered for championing Neptunist geology (originated by Abraham Werner) during its early nineteenth-century competition with the rival Plutonist theory (initiated by James Hutton). Hutton's ideas prevailed and Jameson's intellectual transition to Plutonism is documented in the surviving notes taken by students who attended his lectures at Edinburgh University: one early record is from 1809, a second record is from
c
. 1820 and four sets of notes are from the early 1830s. Of the latter four, two have not been previously considered from a geological perspective and prove to be the most revelatory of Jameson's conversion; notes compiled by the Royal Navy surgeon Robert McCormick are particularly comprehensive. Although Jameson attempted to maintain the essentials of Werner's theory for its well-ordered stratigraphy, he progressively adopted a Plutonist approach to more contentious issues such as the origin of granite, veining and mountain building. Jameson used Edinburgh's Salisbury Crags sill for field demonstrations and the students’ notes illustrate his changing views in terms of the origins of this classic geological feature. Of the students whose lecture notes survive, it is only McCormick for whom Jameson appears to have been a lasting geological influence.
Archean granitoids of the Aravalli Craton, northwest India
Authors: Ahmad Iftikhar , Mondal M. E. A. , Rahaman Md Sayad , Bhutani Rajneesh , Satyanarayanan M.
Published: February 2020

The Archean granitoids of the Aravalli Craton (NW India) are represented by orthogneisses (3.3–2.6 Ga) and undeformed granitoids (
c.
2.5 Ga). Here we present whole-rock geochemical (elemental and Nd-isotope) data of the granitoids from the Aravalli Craton with an aim of understanding the evolution of the continental crust during the Archean. These Archean granitoids have been classified into three compositional groups: (1) TTG – tonalite–trondhjemite–granodiorite; (2) t-TTG – transitional TTG; and (3) sanukitoids. Based on the geochemical characteristics, it is proposed that the TTGs have formed from the partial melting of subducting oceanic plateau. The t-TTG formed owing to reworking of an older continental crust (approximately heterogeneous) in response to tectonothermal events in the craton. For the formation of the sanukitoids, a two-stage petrogenetic model is invoked which involves metasomatization of the mantle wedge, followed by slab breakoff and asthenospheric upwelling, which leads to the melting of asthenosphere and the metasomatized mantle wedge. It is also proposed that subducted sediments contributed to the genesis of sanukitoid magma.
Relevant and flexible geosurveys: how Geological Survey Ireland is adapting
Authors: Verbruggen Koen , Braiden Aoife K. , Lee Monica , Scanlon Ray , Cullen Sean , Finlay Sean
Published: February 2020

Geological Survey Ireland is a division of a government department and has typical origins as a geological survey founded to map the nation's natural resources. In recent years it has changed focus from more traditional geological mapping activities and methods to carrying out major projects of national societal value using, and developing, the latest technology. Programmes include one of the world's largest seabed surveys INFOMAR, a national groundwater mapping and protection programme, and modern geophysical and geochemical mapping under its Tellus programme. In addition the Survey has developed a successful geoscience research programme and a business cluster, Geoscience Ireland. By focusing on stakeholder engagement, effective communication of the value of geoscience and maintaining scientific rigour, geological surveys can be as relevant today as when they were founded.
Production of Hydrogen Peroxide for Drinking Water Treatment in a Proton Exchange Membrane Electrolyzer at Near-Neutral pH
Authors: Li Winton , Bonakdarpour Arman , Gyenge Előd , Wilkinson David P.
Published: February 2020

We provide a detailed report on the electrosynthesis of H2O2 for drinking water treatment under near-neutral conditions using a proton exchange membrane (PEM) electrolyzer. Two novel cathode catalysts for O2 electroreduction to H2O2 were investigated in the PEM electrolyzer: an inorganic cobalt-carbon (Co–C) composite and an organic redox catalyst anthraquinone-riboflavinyl mixed with carbon (AQ–C), respectively. The impact of operational variables such as temperature, cathode carrier water flow rate, and anode configurations (aimed at mitigating carbon corrosion at the anode) were examined in single-pass and full recycle operation. Using a superficial current density of 245 mA cm−2 and an operating temperature of 40 °C, H2O2 molar fluxes of 360 μmol hr−1 cm−2 and 580 μmol hr−1 cm−2 were generated at near-neutral pH with the Co–C and RF-AQ catalysts, respectively. Seventy-two hour experiments with closed loop recirculation, produced H2O2 concentrations of 1300 and 3000 ppm for the Co–C and AQ–C catalysts, respectively. These concentrations are adequate for advanced oxidation (UV/H2O2) treatment of drinking water, rendering the PEM electrolysis approach particularly suitable for on-site and on-demand production of H2O2.
Exploring Different Synthesis Parameters for the Preparation of Metal-Nitrogen-Carbon Type Oxygen Reduction Catalysts
Authors: Teppor Patrick , Jäger Rutha , Härk Eneli , Sepp Silver , Kook Mati , Volobujeva Olga , Paiste Päärn , Kochovski Zdravko , Tallo Indrek , Lust Enn
Published: February 2020

The influence of various synthesis conditions of a metal-nitrogen-carbon (M-N/C) catalyst material on oxygen reduction reaction (ORR) kinetics is discussed. Seven M-N/C catalysts based on cobalt are obtained by changing various synthesis conditions, such as the mixing environment, pyrolysis gas, and post-treatment. The ORR activity and stability measurements are performed using the classical three-electrode configuration in a 0.1 M HClO4 solution. The most active and stable ORR catalyst proves to be the material obtained by mixing a cobalt salt, 2,2’-bipyridine, and a high surface area silicon carbide derived carbon together in water and pyrolyzing the mixture in argon. In a fuel cell test, however, a maximum power density value of 135 mW cm−2 is achieved with the catalyst mixed together in a planetary ball-mill at a low catalyst loading of 1.0 ± 0.1 mg cm−2 and at a test cell temperature of 60 oC despite of the fact that preparing the catalyst via dry ball-milling reduces the surface area of the material roughly 40% more than in the case of using a solution-based method. Consequently, mixing the catalyst precursors together without any additional chemicals in a planetary ball-mill instead of in a solution appears to be the most promising choice.
Interweaving Activated Carbon with Multi-dimensional Carbon Nanomaterials for High-performance Supercapacitors
Authors: Cheng Fang , Yang Xiaoping , Dai Shuya , Song Dan , Zhang Shuangpeng , Lu Wen
Published: February 2020

It has been an important task to improve the properties of conventional activated carbon electrodes to enhance the performances of commercial supercapacitors. Herein, we incorporate multi-dimensional carbon nanomaterials (zero-dimensional carbon black, one-dimensional carbon nanofiber, and two-dimensional graphene) to interweave commercial activated carbon to develop new nanocomposite electrodes for high-performance supercapacitors. Combining the synergistic effects from these multiple components, the resultant nanocomposite electrodes possess a well-packed three-dimensional electrical conduction network and a hierarchical porous structure, thus exhibiting enhanced packing and superior capacitive performances (especially power performances) and cycle life over current supercapacitor technology. The commercial availability of the materials we use indicates the feasibility of our nanocompositing approach in fabricating high-performance supercapacitors with low cost. Furthermore, this approach may be extended to develop superior nanocomposite electrodes for other energy-related devices, such as batteries, fuel cells, and solar cells.
Electric Current in Rate Equation for Parallel Plate Plasma-Enhanced Chemical Vapour Deposition of SiCxNyOz Film without Heat Assistance
Authors: Hori Kenta , Watanabe Toru , Habuka Hitoshi
Published: February 2020

A 50–500 nm-thick SiC
x
N
y
Oz film was formed in parallel plate plasma at room temperature using a gas mixture of monomethylsilane, nitrogen and argon at 10−30 Pa for 5 min at the electric current of 1–16 mA. The film thickness and the concentrations of the silicon, carbon, nitrogen and oxygen were expressed by equations assuming that various chemical reactions in the gas phase and at the surface were enhanced by both the electric current and the partial pressure of the gases. The obtained equations showed the influence of the electric current on the film thickness and the compositions. Using the obtained equations, the existence and the extent of the deposition and the etching by the precursors and their combinations were evaluated.
Chloride Penetration into Concrete under the Coupling Effects of Internal and External Relative Humidity
Authors: Zhu Fangzhi , Ma Zhiming , Zhang Mingmin
Published: February 2020

Chloride penetration frequently happens in an unsaturated concrete; in this case, the chloride migration is under the coupling effects of internal moisture and external relative humidity (RH). Various chloride attack tests were designed in this paper to investigate the effects of internal moisture and external RH (50–100%) on the chloride penetration into an unsaturated concrete, and the chloride content was determined to quantify the chloride migration in concrete. The results highlighted that there was a good correlation between the chloride penetration into concrete and its internal RH. The chloride ion was difficult to penetrate into concrete when its internal RH was below 50%; however, the chloride penetration rate increased when the internal RH of concrete was above 75%, and the chloride migration increased with increasing RH and exposure duration. Water evaporation in concrete increased with decreasing external RH, and an obvious increase in the surface chloride content may be observed when external RH was 50%; however, when external RH was above 75%, the inner chloride content increased and surface chloride content decreased with increasing exposure duration. Simulating the chloride penetration under wet‐dry cycling, the water migration resulted in an increase in the surface chloride content and a decrease in the inner chloride content, and the chloride crystal precipitated on the surface of concrete with a high w/c ratio.
Trading Strategies of a Leveraged ETF in a Continuous Double Auction Market Using an Agent-Based Simulation
Authors: Yagi Isao , Maruyama Shunya , Mizuta Takanobu
Published: February 2020

A leveraged ETF is a fund aimed at achieving a rate of return several times greater than that of the underlying asset such as Nikkei 225 futures. Recently, it has been suggested that rebalancing trades of a leveraged ETF may destabilize the financial markets. An empirical study using an agent-based simulation indicated that a rebalancing trade strategy could affect the price formation of an underlying asset market. However, no leveraged ETF trading method for suppressing the increase in volatility as much as possible has yet been proposed. In this paper, we compare different strategies of trading for a proposed trading model and report the results of our investigation regarding how best to suppress an increase in market volatility. As a result, it was found that as the minimum number of orders in a rebalancing trade increases, the impact on the market price formation decreases.
Displacement Characteristics of an Urban Tunnel in Silty Soil by the Shallow Tunnelling Method
Authors: Zhang Shaobing , He Siyue , Qiu Junling , Xu Wei , Garnes Rodney Sheldon , Wang Lixin
Published: February 2020

The urban shallow tunnelling process in silty soil is easy to cause large displacement of surface and tunnel. Obviously, if the strata and the tunnel face are not treated by reasonable reinforcement method, instability and collapse phenomenon will be encountered during the tunnel excavation. There are a series of studies on construction methods of shallow tunnels, but these methods have limitations in silty soil. In this study, a comprehensive construction plan of the urban shallow tunnel in silty soil was proposed and applied to a case study in Fuzhou, Fujian Province in South China. The in situ monitoring tests and numerical simulation were employed to address displacement characteristics of surface and tunnel. Results indicated that the urban shallow tunnelling process could achieve good effect by dewatering of silty soil, reinforcing surface by vertical jet grouting piles, and advanced small pipes and circumferential grouting in the tunnel face; surface settlement during dewatering process accounted for about 30% of total surface settlement in silty soil; the excavation of the top heading, the middle, and lower benches had great effect on displacement of surface and tunnel for three‐bench seven‐step excavation method in silty soil; surface settlement troughs in silty soil were deeper and wider; lock‐feet bolts had good effect on restricting horizontal convergence; and ratio of total crown settlement and total horizontal convergence was in range of 1.43∼1.59 when b/h was 0.88 in silty soil. The construction plan proposed in this paper is helpful for further study of shallow tunnel tunnelling process in silty soil.
New Strategies in the Code of Uncertainty and Sensitivity Analysis (CUSA) and Its Application in the Nuclear Reactor Calculation
Authors: Du Jiayu , Hao Chen , Ma Ji , Li Peijun , Zhou Xiaoyu , Liu Lixun
Published: February 2020

Best-Estimation Plus Uncertainty (BEPU) analysis method can provide more information to improve the reliability of calculation results than the safety analysis with conservative assumption. And the statistical sampling-based uncertainty and sensitivity analysis methods are widely used in practical applications of the multiphysics, multiscale coupling nuclear reactor system. In this paper, a novel and efficient sampling method for inputs with normal and uniform distributions is introduced and a systematic theory for uncertainty and sensitivity analysis is established based on the classical statistical theory. Then the Code of Uncertainty and Sensitivity Analysis (CUSA) is updated based on these new strategies. For applications, the explicit and implicit effects for resonance and nonresonance isotopes are studied in depth, and a simple UO2 pin cell is considered to examine the performance of CUSA and the total uncertainty and sensitivity analysis abilities. The numerical results indicate that the implicit sensitivity analysis model and the uncertainty quantification functions developed in CUSA are correct and can be used for sensitivity and uncertainty analysis in nuclear reactor calculations. Even more important, the LHS-SVDC is recommended to propagate the uncertainties in multigroup cross sections.
Effects of Corn Stalk Fly Ash (CSFA) on the Mechanical and Deformation Properties of Cemented Coal Gangue Backfill
Authors: Qi Tingye , Wang Haochen , Feng Guorui , Du Xianjie , Wang Zehua , Zhang Shufeng
Published: February 2020

To reduce the amount of cement used in cemented coal gangue backfill (CCGB, a mixture of coal gangue, cement, fly ash, and water), mechanical and deformation properties of CCGB in which CSFA partially replaces the cement (0, 10, 20, 30, and 40 wt%) were studied. Compressive strength, acoustic emission during uniaxial loading, shear strength, and drying shrinkage were analysed. The compressive strength, shear strength, and drying shrinkage tests were performed at different curing times. The results showed that cemented coal gangue and corn stalk fly ash backfill (CGCAB) presented better performance, and the CGCAB with a 20% substitution rate had the best performance at day 28. Despite having the largest drying shrinkage value, 20% is the best choice for the substitution rate of CSFA. A 20% CSFA addition can enhance the bearing capacity of CGCAB and improve its failure mode, which is of great significance to support the upper overburden load and maintain the surface stability of the goaf.