bluuebunny/crossref_metadata_2025 huggingface dataset:
Oestrogen amplifies pre‐existing atopy‐associated Th2 bias in an experimental asthma model
Authors: Lauzon‐Joset Jean Francois , Mincham Kyle T. , Abad Ana P. , Short Braden P. , Holt Patrick G. , Strickland Deborah H. , Leffler Jonatan
Published: December 2019

Background

The prevalence and severity of asthma, particularly the most common (atopic) form of the disease, increase amongst females but not males after puberty, and asthma activity also changes throughout the menstrual cycle and during pregnancy. The contribution of female sex hormones to asthma pathogenesis is incompletely understood.

Objective

To obtain insight into the role of oestrogen (E2) in experimental atopic asthma, and guide future research on sex‐related variations in atopic asthma susceptibility/intensity in humans.

Methods

We utilized an experimental model comprising rat strains expressing dichotomous Th2‐high vs Th2‐low immunophenotypes exemplified by eosinophilia, mirroring differences between human atopics/non‐atopics. We compared the efficiency of Th2‐associated immunoinflammatory mechanisms, which differed markedly between the two strains, and between sexes in the Th2‐high strain, and determined the effects of E2 administration on these differences.

Results

Unique to the Th2‐high strain, eosinophil: neutrophil ratios in the airways at baseline and following sensitization/aeroallergen challenge were logfold higher in females relative to males, and this was reflected by higher baseline blood eosinophil numbers in females. Pretreatment of Th2‐high males with E2 abrogated this sex difference by selectively boosting Th2‐associated genes in the airways and eosinophilia, but was without corresponding effect in the Th2‐low strain. In contrast, parallel E2 effects on myeloid and lymphoid cell populations were relatively modest.

Conclusions and Clinical Relevance

E2 acts to amplify the eosinophilic component of pre‐existing Th2‐high immunophenotype, possibly acting at the level of the common eosinophil/neutrophil precursor in bone marrow to preferentially drive eosinophil differentiation. Constitutive granulocyte profiles in which the balance between eosinophils and neutrophils is skewed towards eosinophils have been identified in independent cohort studies as markers of asthma risk, and these findings suggest that more detailed studies on the role of E2 in this context, and in relation to asthma pathogenesis in post‐pubertal females in particular, appear warranted.
HbS/β+ thalassemia: Really a mild disease? A National survey from the AIEOP Sickle Cell Disease Study Group with genotype‐phenotype correlation
Authors: Notarangelo Lucia Dora , Agostini Annalisa , Casale Maddalena , Samperi Piera , Arcioni Francesco , Gorello Paolo , Perrotta Silverio , Masera Nicoletta , Barone Angelica , Bertoni Elisa , Bonetti Elisa , Burnelli Roberta , Casini Tommaso , Del Vecchio Giovanni Carlo , Filippini Beatrice , Giona Fiorina , Giordano Paola , Gorio Chiara , Marchina Eleonora , Nardi Margherita , Petrone Angela , Colombatti Raffaella , Sainati Laura , Russo Giovanna
Published: December 2019

Objectives

HbS/β+ patients’ presence in Italy increased due to immigration; these patients are clinically heterogeneous, and specific guidelines are lacking. Our aim is to describe a cohort of HbS/β+ patients, with genotype‐phenotype correlation, in order to offer guidance for clinical management of such patients.

Methods

Retrospective cohort study of HbS/β+ patients among 15 AIEOP Centres.

Results

A total of 41 molecularly confirmed S/β+ patients were enrolled (1‐55 years, median 10.9) and classified on β+ mutation: IVS‐I‐110, IVS‐I‐6, promoter, and “others.” Prediagnostic events included VOC 16/41 (39%), ACS 6/41 (14.6%), sepsis 3/41 (3.7%), and avascular necrosis 3/41 (7,3%). Postdiagnostic events were VOC 22/41 (53.6% %), sepsis 4/41 (9.7%), ACS 4/41 (9.7%), avascular necrosis 3/41 (7.3%), aplastic crisis 2/41 (4.8%), stroke 1/41 (2.4%), ACS 1/41 (2.4%), and skin ulcerations 1/41 (2.4%). The IVS‐I‐110 group presented the lowest median age at first SCD‐related event (P = .02 vs promoter group) and the higher median number of severe events/year (0.26 events/patient/year) (P = .01 vs IVS‐I‐6 and promoter groups). Promoter group presented a specific skeletal phenotype. Treatment regimen applied was variable among the centers.

Conclusions

HbS/β+ is not always a mild disease. Patients with IVS‐I‐110 mutation could benefit from a standard of care like SS and S/β° patients. Standardization of treatment is needed.
Comparisons of direct and indirect utilities in adult epilepsy populations: A systematic review
Authors: Foster Emma , Chen Zhibin , Ofori‐Asenso Richard , Norman Richard , Carney Patrick , O'Brien Terence J. , Kwan Patrick , Liew Danny , Ademi Zanfina
Published: December 2019

Objective

Epilepsy is common and carries substantial morbidity, and therefore identifying cost‐effective health interventions is essential. Cost‐utility analysis is a widely used method for such analyses. For this, health conditions are rated in terms of utilities, which provide a standardized score to reflect quality of life. Utilities are obtained either indirectly using quality of life questionnaires, or directly from patients or the general population. We sought to describe instruments used to estimate utilities in epilepsy populations, and how results differ according to methods used.

Methods

We undertook a systematic review of studies comparing at least two instruments for obtaining utilities in epilepsy populations. MEDLINE, Embase, ScienceDirect, Cochrane Library, Google Scholar, and gray literature were searched from inception to June 2019. Mean utilities were recorded and compared for each method.

Results

Of the 38 unique records initially identified, eight studies met inclusion criteria. Utilities were highest for direct "tradeoff" methods, obtained via instruments including standard gamble (0.93) and time tradeoff (0.92), compared to indirect methods, obtained via instruments including EuroQoL five‐dimensional form (range = 0.72‐0.86) and Health Utilities Index Mark 3 (range = 0.52‐0.71). Visual analog scale (VAS), a direct "nontradeoff" instrument, provided equal or lower utilities (range = 68.0‐79.8) compared to indirect instruments.

Significance

Direct methods, with the important exception of VAS, may provide higher utilities than indirect methods. More studies are needed to identify the most appropriate utility instruments for epilepsy populations, and to investigate whether there is variation between utilities for different types of epilepsy and other patient‐ and disease‐specific factors.
On the mechanism of calcium‐dependent activation of NADPH oxidase 5 (NOX5)
Authors: Millana Fañanás Elisa , Todesca Sofia , Sicorello Alessandro , Masino Laura , Pompach Petr , Magnani Francesca , Pastore Annalisa , Mattevi Andrea
Published: December 2019

It is now accepted that reactive oxygen species (ROS) are not only dangerous oxidative agents but also chemical mediators of the redox cell signaling and innate immune response. A central role in ROS‐controlled production is played by the NADPH oxidases (NOXs), a group of seven membrane‐bound enzymes (NOX1‐5 and DUOX1‐2) whose unique function is to produce ROS. Here, we describe the regulation of NOX5, a widespread family member present in cyanobacteria, protists, plants, fungi, and the animal kingdom. We show that the calmodulin‐like regulatory EF‐domain of NOX5 is partially unfolded and detached from the rest of the protein in the absence of calcium. In the presence of calcium, the C‐terminal lobe of the EF‐domain acquires an ordered and more compact structure that enables its binding to the enzyme dehydrogenase (DH) domain. Our spectroscopic and mutagenesis studies further identified a set of conserved aspartate residues in the DH domain that are essential for NOX5 activation. Altogether, our work shows that calcium induces an unfolded‐to‐folded transition of the EF‐domain that promotes direct interaction with a conserved regulatory region, resulting in NOX5 activation.
“One thing leads to another”, but where? – Gateway cities and the geography of production linkages
Authors: Breul Moritz , Revilla Diez Javier
Published: December 2019

Although it has been argued that current configurations of extractive industries provide opportunities for developing production linkages, in other words, that “one thing leads to another”, these opportunities are not necessarily realised directly in the resource‐holding countries. This article aims to explain why the greater opportunities for creating increased production linkages may remain unrealised. While existing research on production linkages is characterised by a national scale mode of analysis, this article examines production linkages in the resource‐poor gateway city of Singapore that are intended to serve oil and gas operations at the macro‐regional level in Indonesia and Vietnam. The results reveal that a significant depth and breadth of production linkages have unfolded in Singapore, highlighting that in particular sophisticated production linkages tend to have a broader geographic scope. Moreover, the analysis identifies factors that have shifted the territorial scale of labour‐intensive and low‐technology production linkages from a macro‐regional towards a national or subnational level, to the advantage of the resource‐holding countries. These insights add some complexity to the study of production‐linkage development and emphasise the need for a multi‐scalar perspective that does not stop at national borders.
‘The group was the only therapy which supported my needs, because it helped me feel normal and I was able to speak out with a voice’: A qualitative study of an integrated group treatment for dual diagnosis service users within a community mental health setting
Authors: Chilton John , Crone Diane M. , Tyson Phiip John
Published: December 2019

Whilst the evidence for the efficacy of treatment interventions for individuals with dual diagnosis has been developing in recent decades, little is known about individual perceptions and the personal benefits of attending integrated treatment programmes within this population group. A qualitative methodology, Interpretive phenomenological analysis, was used to investigate the experiences of individuals with a range of complex mental health and coexisting substance misuse problems who took part in a psychoeducational group (PEG) programme. This comprised of social support and therapeutic peer group relationship facilitation. Semi‐structured interviews were undertaken with 15 service users who successfully participated in this treatment programme. Findings identify the complexity of the therapeutic process and understanding of the treatment from the service users perspective. This included the importance of forming meaningful therapeutic relationships as an influential factor in countering a range of distressing and incompatible environmental and situational stressors, such as self‐regulatory control, self‐awareness of a need for change and the importance of integrated treatment in reducing the sense of stigma and exclusion linked with using mental health services. The study findings support the use of integrated treatment programmes in mental health services with a dual diagnosis population group.
Correlation between neutrophil‐to‐lymphocyte ratio and kidney dysfunction in undiagnosed hypertensive population from general health checkup
Authors: Chen Chen , Zhao Hai Yan , Zhang Yin Hua
Published: December 2019

Recently, neutrophil‐to‐lymphocyte ratio (NLR) and monocyte‐to‐lymphocyte ratio (MLR) are frequently used to evaluate disease progression and outcome. Here, we aim to analyze the associations between NLR or MLR and kidney function in undiagnosed hypertensive individuals from general population during routine health checkup. Liver function was analyzed for comparison. From 2011 to 2016, 53 939 examiners have registered for health checkup in Yanbian University Hospital, Yanbian, China. Among 15 219 participants who have complete datasets, 4997 individuals were hypertensive (HTN, SBP/DBP: ≥ 140/90 mm Hg). NLR, glucose, lipids (Chol, TG, LDL), kidney (CREA, BUN), and liver (AST, ALT, GGT, ALB, TBIL) functional parameters were significantly higher in HTN. Pearman correlation analysis showed that NLR was positively correlated with SBP and CREA only in HTN. MLR was associated with CREA in both HTN and non‐HTN. NLR or MLR was associated with liver functions similarly in HTN and non‐HTN. The authors then divided NLR or MLR into tertiles (NLR: 0‐1.7276, 1.7276‐3, >3; MLR: 0‐0.1845, 0.1845‐0.3, >0.3). NLR was positively associated with BUN at NLR >1.7276 and with CREA at all tertiles in HTN. MLR was correlated with CREA and BUN at high MLR in non‐HTN. Further analysis showed that age or gender did not affect the associations of NLR and MLR with kidney function in HTN, but strong association was observed in male or aged (>65 years old) non‐HTN group. These results showed that NLR could be used as a cost‐effective predictor of kidney abnormality in HTN patients even in a general population.
A new way to reduce the pain of ultherapy treatment
Authors: Liu Hongtao , Zhong Guihong , Liang Lunling , Zhang Mingqi
Published: December 2019

This article describes a case of using intravenous sufentanil in treatment of ultherapy to achieve satisfactory analgesic effect. Further rearchis need to find a convenient, safe and practical method to solve the problem of pain caused by ultherapy treatment.
Location Multiplicative Error Models with Quasi Maximum Likelihood Estimation
Authors: Li Qian
Published: December 2019

Motivated by improving the fitting of non‐negative financial time series, we extend the multiplicative error model and study the semi‐parametric estimation. We first introduce a location parameter and use the sample minimum to a truncate data set. In the case that there is a non‐trivial proportion of zeros in the truncated data, we adopt a zero‐augmented mixture distribution for the innovation terms. For both cases, we propose quasi maximum likelihood estimation for the multiplicative coefficients and establish asymptotic results. We conduct large simulation studies to demonstrate substantial estimation errors with misspecified models, and confirm the asymptotic properties. Moreover, we present an empirical study to illustrate the fitting improvement.
Productivity Shocks and Labour Market Outcomes for Top Earners: Evidence from Italian Serie A
Authors: Carrieri Vincenzo , Jones Andrew M. , Principe Francesco
Published: December 2019

How are top earners affected by productivity shocks? We address this question using a unique longitudinal data set on the universe of professional football players in the Italian Serie A, representing 20% of top earners in Italy. We use traumatic injuries and adopt an IV strategy to provide causal estimates of the impact of productivity shocks on several labour market outcomes. We find that a 30‐day injury substantially affects the probability of contract renegotiation and reduces net wages by around 12%. We show that this large penalty is due to employer's precautionary motives rather than to shock‐induced reduction in current player's performance.
One‐Stage Arthroplasty or Revision for Seronegative Infections in Hip and Knee
Authors: Wang Hao‐yang , Zhang, MD Rui , Luo Ze‐yu , Wang, MD, PhD Duan , Pei Fu‐xing , Tang Xin , Zhou Zong‐ke
Published: December 2019

Objective

To assess the safety and effectiveness of one‐stage total joint arthroplasty (TJA) or revision for seronegative infections after total hip arthroplasty (THA) and total knee arthroplasty (TKA).

Methods

This retrospective study included a total of 495 patients who had undergone one‐stage total joint (hip or knee) arthroplasty or revision with a diagnosis of osteoarthritis secondary to sepsis, osteoarthritis or osteonecrosis of the femoral head (ONFH) secondary to internal fixation surgery of the hip joint, and one‐stage revision for prosthesis loosening after THA or TKA from January 2012 to December 2016. Bacterial cultures were taken from all patients (from joint fluid or articular cavity fluid and four to six different parts of soft tissues) during the operation. If the cultures were positive, patients received antibiotic treatment. Microbiology results from surgical samples, clinical evaluations, SF‐12 score (physical component summary [PCS] and mental component summary [MCS]), Harris hip score (HHS) or Hospital for Special Surgery (HSS) score, and patients' satisfaction was recorded at every follow‐up session.

Results

A total of 24 patients had a positive result for bacterial culture (4.85%). The bacterial culture results showed that there were 19 cases (79.16%) of gram‐positive cocci (Staphylococcus aureus), 4 cases (16.67%) of gram‐negative bacilli, and 1 case (4.17%) of fungi. For at least 24 months (mean 35 months) follow‐up, no reinfection was discovered. The mean HHS or HSS score improved significantly from 36.29 points preoperatively to 84.21 points postoperatively (P < 0.001). The mean PCS score improved from 10.15 preoperatively to 20.34 postoperatively, and the mean MCS from 13.22 preoperatively to 21.76 postoperatively, with significant differences. Most of the patients were satisfied.

Conclusion

One‐stage arthroplasty or revision with exhaustive debridement, adequate dosage, and duration of sensitive antibiotics is safe and effective for patients who have seronegative infection of hip or knee joints.
The dynamics of an interaction between Digitaria sanguinalis and Ustilago syntherismae at local scale is strongly influenced by environment and spatial distribution
Authors: Mas M. T. , Verdú A. M. C.
Published: December 2019

A wild loose smut–summer annual grass interaction was studied to explore the relative importance of some local spatiotemporal patterns of variation for its existence. The prevalence‐related variable measured was the proportion of diseased plants (PDP). The mean annual PDP of nine consecutive seasons (2009–2017) was analysed using a generalized linear model with a binomial distribution considering covariables related to rainfall. During the seasons 2013–2015, the precise location of each sample within the plot was taken into account. The PDP of these seasons was analysed in various ways by means of generalized linear models, searching for its spatial variation with plant density in a given season, and with sorus and seeded inflorescence densities of the previous season. Symptomless plants were estimated as 6.1% of the 2015 population. The mean annual PDP ranged from 0.08 to 0.42 and covaried positively with precipitation. Within the field, two zones could be repeatedly delimited among seasons: one in which high plant densities and high PDP co‐occurred, and another with lower values of both in which PDP depended on the sorus density. The role played by differences in the encounter rate within and among seasons is discussed; lack of encounter could be as necessary as encounter for plant–pathogen coexistence over time.
Impaired early visual categorization of fear in social anxiety
Authors: Meynadasy Melissa , Clancy Kevin , Ke Zijun , Simon Jessica , Wu Wei , Li Wen
Published: December 2019

Social anxiety is associated with biased social perception, especially of ambiguous cues. While aberrations in high‐level processes (e.g., cognitive appraisal and interpretation) have been implicated in such biases, contributions of early, low‐level stimulus processing remain unclear. Categorical perception represents an efficient process to resolve signal ambiguity, and categorical emotion perception can swiftly classify sensory input, “tagging” biologically important stimuli at early stages of processing to facilitate ecological response. However, early threat categorization could be disrupted by exaggerated (or disinhibited) threat processing in anxiety, resulting in biased perception of ambiguous signals. We tested this hypothesis among individuals with low and high trait social anxiety (LSA/HSA; defined relative to the current sample), who performed a two‐alternative forced‐choice (fear or neutral) task on facial expressions parametrically varied along a neutral‐fear continuum. The groups diverged in the reaction time (RT) profile along the neutral‐fear continuum, which was characteristic of categorical perception in the LSA (vs. HSA) group with drastically increased RT from neutral to intermediate (boundary) fear intensities, contrasting monotonic, nonsignificant RT changes in the HSA group. Neurometric analysis along the continuum identified an early neutral‐fear categorization operation (arising in the P1, an early visual ERP at 100 ms), which was nonetheless impaired in the HSA group (due to disinhibited response at the neutral‐fear boundary). Absent group differences in higher‐level cognitive operations (identified by later ERPs), current findings highlight a dispositional cognitive vulnerability in early visual categorization of social threat, which could precipitate further cognitive aberrations and, eventually, the onset of social anxiety disorder.
Evaluating clerkship competency without exams
Authors: Cianciolo Anna T , Hingle Susan , Hudali Tamer , Beason Austin M
Published: December 2019

Background

Using examination scores for grading clerkship threatens students’ engagement at a time when clinical immersion is critical for socialising into medicine. Narratives of student performance, composed during training by multiple preceptors across diverse settings, may be used to judge competence instead. Preceptor commentary is not trusted as a basis for grading, but the alignment between performance narratives and examination scores has not yet been investigated.

Methods

Performance data were gathered retrospectively from five cohorts of internal medicine clerkship students at one institution. The correlation between end‐of‐rotation examination scores and the grading committee's ratings of student competency based on preceptors’ comments was examined. Patterns in the performance narratives of high‐ and low‐scoring students were also explored.

Results

The grading committee's narrative‐based ratings of student competence were correlated with examination scores. The majority of preceptors’ comments were positive and professionalism‐oriented, although students who scored lowest on exams received fewer comments overall and more recommendations for improvement than their highest‐scoring peers. Recommendations for the lowest‐scoring students equally emphasised knowledge, clinical skill and professionalism, whereas recommendations to highest‐scoring students emphasised knowledge and clinical skill at more than twice the rate of professionalism.

Discussion

Clerkship preceptors’ narratives of student performance can inform competency judgements that are grounded in actual workplace learning and are related to the independent examination of knowledge and clinical performance. Using performance narratives as the basis for grading may be a viable approach to balancing learning and assessment needs during core clerkship block rotations.
Assessing the effect of temporal dynamics on urban growth simulation: Towards an asynchronous cellular automata
Authors: Abolhasani Somaie , Taleai Mohammad
Published: December 2019

Time is a fundamental dimension in urban dynamics, but the effect of various definitions of time on urban growth models has rarely been evaluated. In urban growth models such as cellular automata (CA), time has typically been defined as a sequence of discrete time steps. However, most urban growth processes such as land‐use changes are asynchronous. The aim of this study is to examine the effect of various temporal dynamics scenarios on urban growth simulation, in terms of urban land‐use planning, and to introduce an asynchronous parcel‐based cellular automata (AParCA) model. In this study, eight different scenarios were generated to investigate the impact of temporal dynamics on CA‐based urban growth models, and their outputs were evaluated using various urban planning indicators. The obtained results show that different degrees of temporal dynamics lead to various patterns appearing in urban growth CA models, and the application of asynchronous (event‐driven) CA models achieves better simulation results than synchronous models.
Toxoplasma gondii: How fatal is it in pediatric allogeneic bone marrow transplantation setting?
Authors: Komitopoulou Anna , Goussetis Evgenios , Oikonomopoulou Christina , Paisiou Anna , Kaisari Katerina , Ioannidou Eleni , Sipsas Nikolaos V. , Kosmidis Helen , Vessalas Georgios , Peristeri Ioulia , Kitra Vassiliki
Published: December 2019

Toxoplasmosis is a disease of the immunocompetent population. However, cases of toxoplasma infection associated with immunosuppression have been reported, especially the first months after transplantation. Limited data are available about toxoplasma infection, occurring even many months post‐transplant in pediatric patients with nonmalignant and malignant diseases. We report the cases of three patients with early and late disseminated toxoplasmosis and review the literature.
Dormancy cycling: translation‐related transcripts are the main difference between dormant and non‐dormant seeds in the field
Authors: Buijs Gonda , Vogelzang Afke , Nijveen Harm , Bentsink Leónie
Published: December 2019

Primary seed dormancy is a mechanism that orchestrates the timing of seed germination in order to prevent out‐of‐season germination. Secondary dormancy can be induced in imbibed seeds when they encounter prolonged unfavourable conditions. Secondary dormancy is not induced during dry storage, and therefore the mechanisms underlying this process have remained largely unexplored. Here, a 2‐year seed burial experiment in which dormancy cycling was studied at the physiological and transcriptional level is presented. For these analyses six different Arabidopsis thaliana genotypes were used: Landsberg erecta (Ler) and the dormancy associated DELAY OF GERMINATION (DOG) near‐isogenic lines 1, 2, 3, 6 and 22 (NILDOG1, 2, 3, 6 and 22). The germination potential of seeds exhumed from the field showed that these seeds go through dormancy cycling and that the dynamics of this cycling is genotype dependent. RNA‐seq analysis revealed large transcriptional changes during dormancy cycling, especially at the time points preceding shifts in dormancy status. Dormancy cycling is driven by soil temperature and the endosperm is important in the perception of the environment. Genes that are upregulated in the low‐ to non‐dormant stages are enriched for genes involved in translation, indicating that the non‐dormant seeds are prepared for rapid seed germination.
The Earth BioGenome project: opportunities and challenges for plant genomics and conservation
Authors: Exposito‐Alonso Moises , Drost Hajk‐Georg , Burbano Hernán A. , Weigel Detlef
Published: December 2019

Sequencing them all. That is the ambitious goal of the recently launched Earth BioGenome project (Proceedings of the National Academy of Sciences of the United States of America, 115, 4325–4333), which aims to produce reference genomes for all eukaryotic species within the next decade. In this perspective, we discuss the opportunities of this project with a plant focus, but highlight also potential limitations. This includes the question of how to best capture all plant diversity, as the green taxon is one of the most complex clades in the tree of life, with over 300 000 species. For this, we highlight four key points: (i) the unique biological insights that could be gained from studying plants, (ii) their apparent underrepresentation in sequencing efforts given the number of threatened species, (iii) the necessity of phylogenomic methods that are aware of differences in genome complexity and quality, and (iv) the accounting for within‐species genetic diversity and the historical aspect of conservation genetics.
Navigating futures: Anticipation and food supply chain mapping
Authors: Donaldson Andrew , Brice Jeremy , Midgley Jane
Published: December 2019

This paper examines the use of supply chain mapping by actors in the UK food system to anticipate problematic futures. Supply chain mapping as an anticipatory practice is a response to a recent food scare that has reinforced concerns about the safety, quality, and authenticity of foodstuffs circulating within supply chains. Our analysis of this novel set of mapping practices is based around the visibility of the supply chain that they offer and the ways in which this is generated or made to relate to future problems as both objects and processes. Supply chain maps as objects can induce surprise and uncertainty over the future, but they can also demonstrate responsibility for risk or be a means of allocating and assuring accountability for future problems. Looking at mapping as a process highlights both the difficulty of mapping supply chains and what is actually involved in using supply chain maps to give form to potential future problems. We characterise both of these processes as navigational, based on creating and reading “signposts” that allow risky food futures to be plotted as trajectories in space and time. Supply chain maps describe a process as well as a set of spatial relations, and navigating futures with these maps is a skilled task involving accumulated knowledge about food risks and learning to recognise supply chain maps as encompassing time and space. Our analysis highlights how things not made visible by the map, but present through those involved in the mapping, are as important in its anticipatory use as the things made visible. Maps are part of a wider process of making sense of risky food chain futures that is filled with uncertainty and power relations.
Hybrid Method on Clickjacking Detection and Prevention in Modern Advertisements
Authors: Dhurandhar Kirit Shashank , Md Siraj Maheyzah
Published: December 2019

In modern advertisements, clickjacking attacks can be delivered through a vulnerability in web application. To overcome this, web application security is required that will prevent malvertisement. In this study, prevention of clickjacking in the modern web advertisements are implemented. Vulnerability checks on the potentially malicious website were conducted. Implementation of hybrid prevention method of clickjacking into new developed website were carried out. Among top 500 websites, 50 websites were chosen as a dataset in this study out of which 4 case studies were selected. Website with server privileges were required to implement the hybrid prevention method, consisting opacity, Z-Index and X-Frame option policy. A new website was developed to satisfy the requirements for the method implementation. The results show, among 50 selected websites, about 19 websites were vulnerable to clickjacking. When the hybrid prevention method were implemented in the developed website, it increases the security by mitigating the vulnerability of web application to clickjacking attack.
Exercise‐induced hypoglycaemia in type 1 diabetes
Authors: Cockcroft E. J. , Narendran P. , Andrews R. C.
Published: December 2019

New Findings

What is the topic of this review?

Hypoglycaemia is a commonly cited barrier to exercise in type 1 diabetes mellitus (T1D). Knowledge of approaches to prevent or manage exercise‐induced hypoglycaemia can support patients to exercise and help clinicians to give advice. This review presents evidence‐based strategies to prevent exercise‐induced hypoglycaemia in T1D.

What advances does it highlight?

This review highlights approaches that can be used before, during and after exercise to mitigate the risk of hypoglycaemia. The approaches include the timing of exercise, the type of exercise, adjustments to insulin and carbohydrate, use of novel technology and education.

Exercise is a key component for the management of type 1 diabetes mellitus (T1D) and is associated with reduced risk of cardiovascular disease, decreased daily insulin requirements and improved quality of life. Owing to these benefits, people with T1D are recommended to undertake regular physical activity, 150 min per week for adults and 60 min per day for children and adolescents. Despite the recommendations, many people do not meet these targets. One of the commonly cited barriers to exercise is fear of hypoglycaemia along with limited knowledge of effective preventative strategies. Hypoglycaemia can be difficult to predict, and symptoms are often masked during exercise or stress of competition. For athletes with T1D, hypoglycaemia can also limit sporting success. Hypoglycaemia before an event increases the risks of hypoglycaemia during competition and can reduce performance. To avoid hypoglycaemia, people with T1D may avoid exercise altogether or consume excessive amounts of carbohydrates, which mitigates many of the health benefits of exercise. Increased understanding of approaches to prevent or manage hypoglycaemia is therefore important to help increase levels of physical activity in people with T1D and to support athletes with T1D to compete at the highest level. This review outlines the prevalence of exercise‐related hypoglycaemia, its underlying physiology and the strategies that can be used to prevent and manage exercise‐induced hypoglycaemia in T1D. Our hope is that this knowledge will be used by people with T1D and their clinicians to find individual approaches to manage exercise‐related hypoglycaemia.
Synthesis of Hollow Microspheres LiNi0.5Mn1.5O4 Coated With Al2O3 and Characterization of the Electrochemical Capabilities
Authors: Li Shiyou , Liang Wenbiao , Xie Jing , Wei Yuan , Cui Xiaoling
Published: December 2019

Spinel LiNi0.5Mn1.5O4 (LNMO) has become one of the most practical power lithium-ion battery cathode materials due to its advantages of three-dimensional Li+ diffusion channel, higher potential window (3.5–5V), high-energy density (∼660 Wh/kg), and high-power density. In this manuscript, a hollow spherical LNMO material with large size and high crystallinity is prepared by a modified coprecipitation method using ethyl alcohol as a peptizator. Subsequently, the prepared LNMO material is further modified by an Al2O3 coating to improve its cycle stability. Results show that the initial discharge-specific capacity of LNMO material with 1 wt% Al2O3 coating is 133.7 mAh g−1 at 0.2 C rate, and the capacity retention rate is 97.7% after 100 cycles. The effective increase in the cycle life of the battery can be attributed to the uniform and dense Al2O3 coating on the surface of the material.
Cathode Chemistries and Electrode Parameters Affecting the Fast Charging Performance of Li-Ion Batteries
Authors: Zhao Rui , Liu Jie , Ma Fai
Published: December 2019

Li-ion battery fast-charging technology plays an important role in popularizing electric vehicles (EV), which critically need a charging process that is as simple and quick as pumping fuel for conventional internal combustion engine vehicles. To ensure stable and safe fast charging of Li-ion battery, understanding the electrochemical and thermal behaviors of battery electrodes under high rate charges is crucial, since it provides insight into the limiting factors that restrict the battery from acquiring energy at high rates. In this work, charging simulations are performed on Li-ion batteries that use the LiCoO2 (LCO), LiMn2O4 (LMO), and LiFePO4 (LFP) as the cathodes. An electrochemical-thermal coupling model is first developed and experimentally validated on a 2.6Ah LCO based Li-ion battery and is then adjusted to study the LMO and LFP based batteries. LCO, LMO, and LFP based Li-ion batteries exhibited different thermal responses during charges due to their different entropy profiles, and results show that the entropy change of the LCO battery plays a positive role in alleviating its temperature rise during charges. Among the batteries, the LFP battery is difficult to be charged at high rates due to the charge transfer limitation caused by the low electrical conductivity of the LFP cathode, which, however, can be improved through doping or adding conductive additives. A parametric study is also performed by considering different electrode thicknesses and secondary particle sizes. It reveals that the concentration polarization at the electrode and particle levels can be weaken by using thin electrodes and small solid particles, respectively. These changes are helpful to mitigate the diffusion limitation and improve the performance of Li-ion batteries during high rate charges, but careful consideration should be taken when applying these changes since they can reduce the energy density of the batteries.
Theoretical Analysis for Combined Compact Evaporative Cooler Utilizing Nanostructured Surfaces
Authors: Ismael Laith , Ma Hongbin
Published: December 2019

A detailed mathematical model is modified that describes heat and mass transfer through Combined Compact Evaporative Cooler CCEC using mono-scale sintered particles coating. The model accounts for the effects of particles size, Reynold’s number, and channel spacing on system performance for certain operating conditions. In this study, a Kelvin-Clapeyron equation is utilized to obtain numerical data for an evaporating meniscus in the wet channels and compared to the plain surface. The results indicate that porous coatings enhanced evaporative heat and mass transfer in the wet channels significantly, compared to the plain wet channels walls, due to wicking water that covers entire heated surfaces.
Experimental Investigation of a Miniature Ejector Using Water As Working Fluid
Authors: Dong Jingming , Xia Yuxin , Ma Hongbin , Song He , Zhao Zhongxi , Liang Tao
Published: December 2019

This paper presents an experimental investigation of a miniature ejector using water as the working fluid. The investigated ejector cooling system can be used to keep the temperature of an electric chip below ambient temperature. The authors tested the effects of working conditions, the nozzle exit position (NXP), and the area ratio on the ejector’s performance. Experimental results show that the miniature ejector works well in the high-temperature evaporator (HTE) under temperatures ranging from 55 °C to 70 °C and can achieve a 0.66 coefficient of performance (COP). With the increase of the NXP, the COP decreased, while the critical condensing pressure first increased and then decreased. As the area ratio of the miniature ejector increased, the COP increased, and the critical condensing pressure decreased.
A Novel Thermal Solution for Electronics: Alumina Flat-Plate Oscillating Heat Pipe
Authors: Tian Bohan , Ma Hongbin , Deming Yang , Xu Jiujun , Wang Zhiyong , Zhao Nannan
Published: December 2019

The heat flux in electronics requires the thermal management of printed circuit boards (PCBs) using two-phase cooling methods. In this study, an integrated ceramic heat transfer device, the alumina flat-plate oscillating heat pipe, is developed. The device was fabricated by pressing and sintering procedures, and the inner serpentine channels were simultaneously formed during sintering without brazing or separated caps. This novel manufacturing process simplifies the fabrication of the macrochannels inside ceramic devices and provides a new method for fabricating ceramic two-phase cooling devices. This paper presents an analysis of the internal channel’s formation mechanism and illustrates the major factors of densification. Micro-computed tomography (Micro-CT) scanning was adopted to assess the macrostructure, and SEM was used to characterize the microstructure of the alumina OHP. Water was charged inside the device as the working fluid. The effects of the power input, orientation, operating temperature and filling ratio on the heat transfer performance were investigated. The experimental results show that the alumina OHP has a high heat transport capability. When the OHP structure is embedded inside the alumina and charged with water, the thermal resistance can be reduced by 97%.
Three-Dimensional Simulation of Bubble Behavior and Mass Transfer for CO2 Absorption in Nanoabsorbents
Authors: Li Lirong , Kang Yong Tae
Published: December 2019

CO2 absorption performance in gas-liquid system is affected by nanoparticles. The enhancement mechanisms involved have been extensively paid attention. The CO2 gas bubble behaviors and the characteristics of the nanoparticle motion have been clarified in the present study. The equivalent substitution method is used to regard the liquid with nanoparticles as a continuous term with changed physical properties, that is, nanofluid. Therefore, the volume-of-fluid (VOF) method is employed to well predict the gas bubble behaviors and mass transfer coefficient in nanofluid. It is found that the mass transfer coefficient in the gas-liquid system for CO2 absorption can be significantly enhanced by Al2O3 nanoparticles. With the increase of nanoparticles volume concentration, the surface renewal frequency increases dramatically. The discrete-particle-method (DPM) is adopted to track the motion of nanoparticles. In this way, the deformation of the bubbles and the motion of the nanoparticle are well captured. It is concluded that the enhanced mass transfer coefficient in gas-liquid-nanoparticle system is not only related to the Brownian motion of the particles, but also related to the nanoparticle deduced turbulence in the liquid field.
Theoretical Analysis of Evaporation Heat Transfer in the Thin-Film Region of Nanofluids
Authors: Zhao Nannan , Lin Huan , Su Fengmin , Fu Benwei , Ma Hongbin , Tian Bohan
Published: December 2019

A significantly higher heat transfer coefficient can be achieved through thin-film evaporation. Nanofluids also have significant enhancements in heat transfer. In the current investigation, based on the principle of conservation of momentum and the Young-Laplace equation, considering the effects of bulk flow and nanofluids concentration variation, a mathematical model of evaporative heat transfer of nanofluids is established. The different performances of different concentrations of nanofluids in the thin film evaporation heat transfer process are discussed. The results show that with the change of nanofluids concentration, the surface tension, dynamic viscosity, thermal conductivity and density will be changed, and surface tension plays an important role in the thin film evaporation heat transfer process. That will lead to a significant effect on the thin-film profile, interface temperature, heat flux in the thin-film region of the nanofluids.
Near-Field Radiative Heat Transfer Between Mie Resonance-Based Metamaterials Made of Coated Nonmagnetic Particles
Authors: Lu Lu , Song Jinlin , Zhou Kun , Cheng Qiang
Published: December 2019

Near-field radiative heat transfer between Mie resonance-based metamaterials composed of SiC/d-Si (silicon carbide and doped silicon) core/shell particles immersed in aligned nematic liquid crystals are numerically investigated. The metamaterials composed of core/shell particles exhibit superior performances of enhanced heat transfer and obvious modulation effect when compared to that without shell. The underlying mechanism can be explained that the excitation of Fröhlich mode and epsilon-near-zero (ENZ) resonances both contribute to the total heat flux. Modulation of near-field radiative heat transfer can be realized with the host material of aligned nematic liquid crystals. The largest modulation ratio could be achieved as high as 0.45 for metamaterials composed of core/shell SiC/d-Si particles, and the corresponding heat flux is higher than other similar materials such as LiTaO3/GaSb and Ge/LiTaO3. While with the same volume filling fraction, the modulation ratio of that composed of SiC particles is only 0.2. We show that the core/shell nanoparticles dispersed liquid crystals (NDLCs) have a great potential in enhancing the near-field radiative heat transfer in both the p and s polarizations with the radii of 0.65 μm, and Mie-metamaterials are shown for the first time to modulate heat flux within sub-milliseconds.
Numerical Investigation of Flow Boiling in a Manifold Microchannel Heat Sink With Conjugate Heat Transfer
Authors: Sun Zhichuan , Luo Yang , Li Junye , Li Wei , Zhang Jingzhi , Zhang Zhengjiang , Wu Jie
Published: December 2019

The manifold microchannel heat sink receives an increasing number of attention lately due to its high heat flux dissipation. Numerical investigation of boiling phenomena in manifold microchannel (MMC) heat sinks remains a challenge due to the complexity of fluid route and the limitation of numerical accuracy. In this study, a computational fluid dynamics (CFD) approach including subcooled two-phase flow boiling process and conjugate heat transfer effect is performed using a MMC unit cell model. Different from steady-state single phase prediction in MMC heat sink, this type of modeling allows for the transient simulation for two-phase interface evolution during the boiling process. A validation case is conducted to validate the heat transfer phenomenon among three phases. Besides, this model is used for the assessment of the manifold dimensions in terms of inlet and outlet widths at the mass flux of 1300 kg/m2·s. With different ratios of inlet-to-outlet area, the thermal resistances remain nearly stable.
Molecular Dynamics Study on Effect of Interface Between Silicon and Silicon Carbide Crystals on Phonon Heat Conduction on Nanoscale
Authors: Nie Xianhua , Zhao Li , Deng Shuai , Zhang Yue , Du Zhenyu
Published: December 2019

Both silicon (Si) and silicon carbide (SiC) are promising materials used in nano-electro-mechanical system (NEMS), however, the understanding on its phonon heat conduction is rare, which restrict the performance improvement of NEMS. Moreover, the effects of the interface between crystals, which could significantly impact the phonon transport, on heat conduction are not sufficient in the existing publication pool. In this paper, two systems, Si/Si and Si/SiC, are simulated at different temperatures and temperature differences using molecular dynamics simulation and the results were analyzed.

The temperature of Si inside Si/SiC system was set at 280K, and the temperatures of SiC were set as a certain absolute value based on temperature difference setting. Meanwhile, 6 groups of temperature difference are applied as simulated conditions. In addition, simulated results from Si/Si system are also applied in comparative analysis as a reference group. The results suggested that the existence of the interface of Si/SiC system would reduce the capability of heat conduction compared to the heat conduction of Si/Si and reverse temperature differences are discovered. When the average temperature is higher than 280K, the heat conduction rate of Si/SiC system is higher than that of Si/Si system initially and as the temperature differences between crystals increases to 60.90K, the heat conduction rate of Si/Si system is higher than that of Si/SiC system. Similar conclusion can also be obtained when the average temperature is lower than 280K. This work provides an open opportunity to study the effect of interface on phonon heat conduction between crystals at typical temperature differences and average temperatures.