bluuebunny/crossref_metadata_2025 huggingface dataset:
A Bayesian spatiotemporal model of panel design data: Airborne particle number concentration in Brisbane, Australia
Authors: Clifford Sam , Low‐Choy Samantha , Mazaheri Mandana , Salimi Farhad , Morawska Lidia , Mengersen Kerrie
Published: August 2019

In environmental monitoring, the ability to obtain high‐quality data across space and time is often limited by the cost of purchasing, deploying and maintaining a large collection of equipment, and the employment of personnel to perform these tasks. An ideal design for a monitoring campaign would be dense enough in time to capture short‐range variation at each site, long enough in time to examine trends at each site and across all sites, and dense enough in space to allow modelling of the relationship between the means at each of the sites. This paper outlines a methodology for semiparametric spatiotemporal modelling of data that is dense in time but sparse in space, obtained from a split panel design, the most feasible approach to covering space and time with limited equipment. The data are hourly averaged particle number concentration (PNC) and were collected as part of the International Laboratory for Air Quality and Health's Ultrafine Particles from Traffic Emissions and Children's Health (UPTECH) project. The panel design comprises two weeks of continuous measurements taken at each of a number of government primary schools in the Brisbane Metropolitan Area, with each school visited sequentially. The school data are augmented by data from long‐term monitoring stations at three locations in Brisbane, Australia. The temporal part of the model explains daily and weekly cycles in PNC at the schools. The temporal variation is modelled hierarchically with a penalised random walk term common to all sites and a similar term accounting for the remaining temporal trend at each site. The modelling of temporal trends requires an acknowledgement that the observations are correlated rather than independent. At each school and long‐term monitoring site, peaks in PNC can be attributed to the morning and afternoon rush hour traffic and new particle formation events. The spatial component of the model describes the school‐to‐school variation in mean PNC at each school and within each school ground. The spatial term in the model is derived from a stochastic partial differential equation and approximates a Gaussian process with a Gaussian Markov Random field. Fitting the model helps describe spatial and temporal variability at a subset of the UPTECH schools and the long‐term monitoring sites, which can be used to estimate the exposure of school children to ultrafine particles. Parameter estimates and their uncertainty are computed in a computationally efficient approximate Bayesian inference environment, R‐INLA.
Ammonia Scavenging Prevents Progression of Fibrosis in Experimental Nonalcoholic Fatty Liver Disease
Authors: De Chiara Francesco , Thomsen Karen Louise , Habtesion Abeba , Jones Helen , Davies Nathan , Gracia‐Sancho Jordi , Manicardi Nicolò , Hall Andrew , Andreola Fausto , Paish Hannah L. , Reed Lee H. , Watson Abigail A. , Leslie Jack , Oakley Fiona , Rombouts Krista , Mookerjee Rajeshwar Prosad , Mann Jelena , Jalan Rajiv
Published: August 2019

Background and Aims

In nonalcoholic fatty liver disease (NAFLD), fibrosis is the most important factor contributing to NAFLD‐associated morbidity and mortality. Prevention of progression and reduction in fibrosis are the main aims of treatment. Even in early stages of NAFLD, hepatic and systemic hyperammonemia is evident. This is due to reduced urea synthesis; and as ammonia is known to activate hepatic stellate cells, we hypothesized that ammonia may be involved in the progression of fibrosis in NAFLD.

Approach and Results

In a high‐fat, high‐cholesterol diet–induced rodent model of NAFLD, we observed a progressive stepwise reduction in the expression and activity of urea cycle enzymes resulting in hyperammonemia, evidence of hepatic stellate cell activation, and progressive fibrosis. In primary, cultured hepatocytes and precision‐cut liver slices we demonstrated increased gene expression of profibrogenic markers after lipid and/or ammonia exposure. Lowering of ammonia with the ammonia scavenger ornithine phenylacetate prevented hepatocyte cell death and significantly reduced the development of fibrosis both in vitro in the liver slices and in vivo in a rodent model. The prevention of fibrosis in the rodent model was associated with restoration of urea cycle enzyme activity and function, reduced hepatic ammonia, and markers of inflammation.

Conclusions

The results of this study suggest that hepatic steatosis results in hyperammonemia, which is associated with progression of hepatic fibrosis. Reduction of ammonia levels prevented progression of fibrosis, providing a potential treatment for NAFLD.
Single amyloid‐beta injection exacerbates 4‐aminopyridine‐induced seizures and changes synaptic coupling in the hippocampus
Authors: Alcantara‐Gonzalez David , Villasana‐Salazar Benjamín , Peña‐Ortega Fernando
Published: August 2019

Accumulation of amyloid‐beta (Aβ) in temporal lobe structures, including the hippocampus, is related to a variety of Alzheimer's disease symptoms and seems to be involved in the induction of neural network hyperexcitability and even seizures. Still, a direct evaluation of the pro‐epileptogenic effects of Aβ in vivo, and of the underlying mechanisms, is missing. Thus, we tested whether the intracisternal injection of Aβ modulates 4‐aminopyridine (4AP)‐induced epileptiform activity, hippocampal network function, and its synaptic coupling. When tested 3 weeks after its administration, Aβ (but not its vehicle) reduces the latency for 4AP‐induced seizures, increases the number of generalized seizures, exacerbates the time to fully recover from seizures, and favors seizure‐induced death. These pro‐epileptogenic effects of Aβ correlate with a reduction in the power of the spontaneous hippocampal network activity, involving all frequency bands in vivo and only the theta band (4–10 Hz) in vitro. The pro‐epileptogenic effects of Aβ also correlate with a reduction of the Schaffer‐collateral CA1 synaptic coupling in vitro, which is exacerbated by the sequential bath application of 4‐AP and Aβ. In summary, Aβ produces long‐lasting pro‐epileptic effects that can be due to alterations in the hippocampal circuit, impacting its coordinated network activity and its synaptic efficiency. It is likely that normalizing synaptic coupling and/or coordinated neural network activity (i.e., theta activity) may contribute not only to improve cognitive function in Alzheimer's disease but also to avoid hyperexcitation in conditions of amyloidosis.
Interaction of Cu and Ag nanoparticles on MHD water‐based nanofluids past a stretching sheet
Authors: Nayak B. , Mishra S. R. , Tripathy R. S.
Published: August 2019

The study explores the MHD flow of water‐based nanofluids past a stretching sheet that melts at a constant rate. Cu and Ag nanoparticles are considered to merge into the base fluid to discuss the flow, heat and mass transfer characteristics. Suitable transformation is employed to transform the governing partial differential equations to a system of nonlinear coupled ordinary differential equations (ODEs). A semi‐analytical technique, that is, in particular, the Adomian decomposition method is implemented to tackle this system of ODEs. The influences of characterizing parameters for the flow phenomena are determined via graphs and displayed. Furthermore, the computed values of the quantities of engineering interest are exhibited through tables and discussed. The main findings of the results are laid down as follows: the Cu‐water nanofluid momentum is more pronounced than that of Ag‐water due to the heavier density of the Ag nanoparticles and an increasing melting parameter is favorable to decrease the fluid temperature, which is useful for the cooling of the substances at the final stage of production in industries.
Helicobacter pylori infection, chronic atrophic gastritis and risk of stomach and esophagus cancer: Results from the prospective population‐based ESTHER cohort study
Authors: Holleczek Bernd , Schöttker Ben , Brenner Hermann
Published: August 2019

Helicobacter pylori (H. pylori) infection is considered as principal cause of gastric cancer. It is further associated with a reduced risk of esophageal adenocarcinomas. In a large prospective population‐based cohort study including 9,949 subjects with average observation time of 13.8 years, we assessed the risk of invasive gastric and esophageal cancer according to H. pylori infection and presence of chronic atrophic gastritis (CAG). Incidence rates and hazard ratios (HR) derived by Cox proportional hazards models and adjusted for relevant confounders were derived by seroprevalence of H. pylori and cytotoxin‐associated gene A (CagA) antibodies and presence of CAG based on serological markers at baseline, respectively. During follow‐up, 30 cases of noncardia gastric cancer and 33 cases of esophageal cancer were observed. Infection by H. pylori without and with expression of CagA was associated with a 5.2‐fold (95% confidence interval 1.00–27.1) and an 18.2‐fold (4.3–77.4) increase of noncardia gastric cancer incidence. A 0.65‐fold decreased risk of esophageal adenocarcinomas (HR 0.35, 0.12–0.97) was observed among H. pylori‐infected individuals. In participants infected with CagA expressed H. pylori, the presence of mild/moderate and severe CAG was associated with a 6.4‐fold (1.3–31.0) and an 11.8‐fold (3.1–45.4) increase of gastric cancer incidence, respectively. The results of this prospective population‐based cohort study may contribute relevant evidence to the ongoing research of H. pylori‐related cancers. The results may furthermore enhance the empirical basis for risk stratification among H. pylori‐infected people and for recommendations regarding H. pylori screening and treatment among older adults in a Western population.
Understanding the Role of Surface Oxygen in Hg Removal on Un‐Doped and Mn/Fe‐Doped CeO2(111)
Authors: Liu Ping , Ling Lixia , Lin Hao , Wang Baojun
Published: August 2019

Effects of surface‐adsorbed O and lattice O for the CeO2(111) surface on Hg removal has been researched. In this work, periodic calculations based on density functional theory (DFT) were performed with the on‐site Coulomb interaction. Hg is oxidized to HgO via the surface‐adsorbed O by overcoming a Gibbs free energy barrier of 114.1 kJ·mol−1 on the CeO2(111) surface. Mn and Fe doping reduce the activation Gibbs free energy for the Hg oxidation, and energies of 70.7 and 49.6 kJ·mol−1 are needed on Ce0.96Mn0.04O2(111) and Ce0.96Fe0.04O2(111) surfaces. Additionally, lattice O also plays an important role in Hg removal. Hg cannot be oxidized leading to the formation of HgO on the un‐doped CeO2(111) surface owing to the inertness of lattice O, which can be easily oxidized to HgO on Ce0.96Mn0.04O2(111) and Ce0.96Fe0.04O2(111) surfaces. It can be seen that both surface‐adsorbed O and lattice O play important roles in removing Hg. The present study will shed light on understanding and developing Hg removal technology on un‐doped and Mn/Fe‐doped CeO2(111) catalysts. © 2019 Wiley Periodicals, Inc.
Additive‐dependent iptycene incorporation in polyanilines: Insights into the pentiptycene clipping effect and the polymerization mechanism
Authors: Tan Wei Shyang , Lee Ting‐Yin , Tseng Sheng‐Fang , Hsu Ying‐Feng , Ebina Masanori , Taketsugu Tetsuya , Huang Shing‐Jong , Yang Jye‐Shane
Published: August 2019

Despite the long history of polyaniline chemistry, backbone‐substituted polyanilines are limited. Here, we report the synthesis of pentiptycene‐incorporated polyanilines through acidic aniline oxidative polymerization with three pentiptycene derivatives, TA, DA, and TP, as nucleate additives. The reactivity of TA > DA ≫ TP, as evidenced by structural and property analysis of the corresponding polyaniline products, demonstrates a radical coupling mechanism and the formation of Dewar π‐complex intermediates for the chain propagation. In addition, the iptycene substituent effect on enhancing the electrochemical stability and charge storage capability of polyaniline are discussed with a clip model, namely, the threading of neighboring polyaniline chains through the U‐ and V‐shaped cavities of pentiptycene restricts lateral motions of the polymer chains and promotes interchain conductivity. Density function theory (DFT) calculations suggest a larger clipping effect for the U versus V cavities. Both the conclusion of a terminal planar p‐phenylenediamine (ppda) group being the key component of an effective nucleate and the concept of interchain clipping for enhanced electrochemical performance should facilitate the design and synthesis of novel polyanilines for electronic applications.
Preparation of a fiberglass‐supported Ni‐Si‐Ti oxide catalyst for oxidation of hydrocarbons: effect of SiO2
Authors: Brichkov Anton S , Shamsutdinova Anastasiya N , Khalipova Olga S , Rogacheva Anastasiya O , Larina Tatyana V , Glazneva Tatyana S , Cherepanova Svetlana V , Paukshtis Evgeny A , Buzaev Alexander A , Kozik Vladmir V , Chen Yu‐Wen
Published: August 2019

BACKGROUND

Preparation of homogeneous oxide coatings on the surface of fiberglass is a difficult task due to hydrophobicity of the fiberglass support. NiO‐TiO2 cannot coat the fiberglass surface homogeneously. In the present study, SiO2 was added in the NiO‐TiO2. A sol–gel method was used to prepare Ni‐Si‐Ti sol and this was used to coat fiberglass and form a complex Ni‐Si‐Ti oxide system supported on its surface. The catalyst was tested for hydrocarbon oxidation reaction.

RESULTS

The as‐prepared material is a mixture of TiO2 in the anatase modification and SiO2 in the amorphous phase. UV‐visible diffusion reflectance spectroscopy confirmed the presence of Ni2+Oh cations in the film bulk. Introduction of silica to the sample ensured a uniform distribution of the NiTi oxide system on the fiberglass surface and its durable retention there at 600 °C. The Ni‐Si‐Ti mixed oxide supported on fiberglass demonstrated a higher catalytic activity in the oxidation of n‐heptane, compared to NiTi oxide/fiberglass catalyst. It is stable even at 600 °C, the temperature at which the maximum n‐heptane conversion of 93% was reached.

CONCLUSION

Adding SiO2 in NiO‐TiO2 can coat fiberglass homogeneously as SiO2 can coat hydrophobic surfaces such as fiberglass. This research provides a method with which to coat metal oxide catalyst on fiberglass that is very active and stable for oxidation of hydrocarbons even at high temparatures, compared to that without adding SiO2. © 2019 Society of Chemical Industry
Fouling resistant sericin‐coated polymeric microfiltration membrane
Authors: Verma Vishal Kumar , Subbiah Senthilmurugan
Published: August 2019

BACKGROUND

Greywater and produced water are undoubtedly valuable resources for reclaimed water, which can lessen the burden on use of freshwater. However, most often the membrane technology used for treatment of greywater and produced water suffers massively from fouling‐related issues. In the present study, a novel and facile method is successfully developed for modification of polypropylene (PP) microfiltration (MF) membrane via surface coating with sericin for imparting better antifouling properties.

RESULT

The membrane hydrophilicity significantly improved after sericin coating and exhibited high water content (64.87%) and low water contact angle (38°). In a comparative study with synthetic greywater, the sericin‐coated membrane removed <90% turbidity and produced a greater volume of purified water with 15% less fouling compared to the uncoated membrane. The fouling experiment concludes that the sericin‐coated membrane can reduce reversible and irreversible fouling by ≈30% and ≈83.00%, respectively, relative to the uncoated membrane using pure water backwash operation. In the second case, the sericin‐coated membrane was able to provide consistent permeate quality with produced water: chemical oxygen demand <43 ppm, biological oxygen demand <6.8 ppm, suspended solids completely removed, total dissolved solids <112 ppm, turbidity <5 NTU and oil content <0.044 ppm, together with 10.5% less fouling than uncoated membrane.

CONCLUSION

This study reveals that sericin coating enhanced membrane hydrophilicity and hence exhibited better antifouling properties. The sericin‐coated MF membrane effectively treated greywater as well as produced water with less fouling and within limits of national standards for reusability. © 2019 Society of Chemical Industry
Assessment of service refinement and its impact on repeat HIV testing by client's access to Australia's universal healthcare system: a retrospective cohort study
Authors: Ryan Kathleen E , Wilkinson Anna L , Asselin Jason , Leitinger David P , Locke Peter , Pedrana Alisa , Hellard Margaret , Stoové Mark
Published: August 2019

Introduction

Achieving the virtual elimination of HIV requires equitable access to HIV prevention tools for all priority populations. Restricted access to healthcare means migrants face particular barriers to HIV prevention services. In February 2016, a peer‐led rapid HIV testing service for gay, bisexual and other men who have sex with men (gay and bisexual men, GBM) in Melbourne, Australia, introduced free sexually transmissible infection (STI) testing funded through Medicare (Australia's universal healthcare system). Medicare ineligible migrant clients were required to pay up to $158AUD for STI tests. We determined the uptake of STI testing and assessed the impact on repeat HIV testing among Medicare eligible and ineligible clients.

Methods

All HIV tests conducted between August 2014 and March 2018 were included. We describe client characteristics, STI testing uptake and HIV/STI positivity among Medicare eligible and ineligible clients. Repeat HIV testing, assessed as the percentage of HIV tests with a return test within six months, was compared pre‐integration (August 2014‐June 2016) and post‐integration(July 2016‐March 2018) of STI testing using segmented linear regression of monthly aggregate data for Medicare eligible and ineligible clients.

Results

Analyses included 9134 HIV tests among 4753 individuals. Medicare ineligible clients were younger (p < 0.01), and fewer reported previously testing for HIV (p < 0.01) and high HIV risk sexual behaviours. There was no difference in HIV positivity between the two groups (p = 0.09). STI testing uptake was significantly lower among Medicare ineligible clients (7.6%, 85.3%; p < 0.01). Following STI testing introduction there was an immediate increase in six‐month return HIV testing (6.4%; p = 0.02) and a significantly increasing rate of return HIV testing between July 2016 and March 2018 (0.5% per month; p < 0.01) among Medicare eligible clients but no immediate change in return testing (−0.9%; p = 0.7) or the rate of change in return testing between July 2016 and March 2018 (0.1% per month; p = 0.3) among Medicare ineligible clients. In March 2018, six‐month return HIV testing was 52.3% and 13.2% among Medicare eligible and ineligible clients respectively.

Discussion

Improvements in return HIV testing observed among Medicare eligible clients did not extend to Medicare ineligible clients highlighting the impact of inequitable access to comprehensive sexual healthcare on test‐and‐treat approaches to HIV prevention.
Mobilizing civil society for the HIV treatment cascade: a global analysis on democracy and its association with people living with HIV who know their status
Authors: Tan Rayner KJ , Wong Chen Seong
Published: August 2019

Introduction

Civil society organizations (CSOs) play an essential role in the global HIV/AIDS response. Past studies have described the beneficial role of CSOs in meeting the United Nations Programme on HIV/AIDS (UNAIDS) 90‐90‐90 target, but have not explored how political conditions, which influence the ability of CSOs to organize, have an impact on the cascade. This study explores the relationship between measures of democracy and its association with diagnosis rates among people living with HIV (PLHIV).

Methods

This study analyses 2016 data derived from the Economist Intelligence Unit's Democracy Index (EIUDI), UNAIDS country estimates for PLHIV and PLHIV who knew their status in 2016, World Bank's 2016 data on nominal gross domestic product (GDP) per capita and country population, HIV Justice Network's 2016 data on HIV criminalization, and country‐level estimates for PLHIV, PLHIV who know their status, and expenditure on HIV prevention from other independent sources. An estimated HIV prevalence variable was constructed by dividing the estimated PLHIV population with the total population of a country. Analyses were limited to countries with available data on PLHIV who know their status (n = 111).

Results

Of the 111 countries in the analytic sample, the mean democracy index score was 5.93 (of the 10), median estimated HIV prevalence was 0.20% (IQR 0.10‐0.65), median GDP per capita (in thousands, US dollar) was 4.88 (IQR 2.11‐13.79), and mean PLHIV who know their status is 67.12%. Preliminary analysis on the five component measures of the EIUDI revealed multicollinearity, and thus the composite democracy index score was used as the measure for democracy. Multivariate linear regression analyses revealed that democracy index scores (β = 2.10, SE = 1.02, p = 0.04) and GDP per capita (in thousands; β = 0.34. SE = 0.11, p < 0.01) were positively associated with diagnosis rates among PLHIV, controlling for country‐level expenditure on HIV prevention, HIV criminalization laws and estimated HIV prevalence.

Conclusions

Results indicate that higher levels of democracy were positively associated with rates of diagnosis among PLHIV. Further analyses following wider implementation of universal testing and treatment is warranted, as well as the need for further research on the mechanisms through which political cultures specifically influence rates of diagnosis among PLHIV.
The upside-downside nature of Vitamin D signaling in liver
Authors: Scott Melanie J
Published: August 2019

Discussion of the potential contradictory effects of vitamin D receptor signaling in a mouse model of autoimmune hepatitis.
Frontline Science: Exhaustion and senescence marker profiles on human T cells in BRGSF-A2 humanized mice resemble those in human samples
Authors: Labarthe Laura , Henriquez Soledad , Lambotte Olivier , Di Santo James P. , Le Grand Roger , Pflumio Françoise , Arcangeli Marie-Laure , Legrand Nicolas , Bourgeois Christine
Published: August 2019

This work sought to confirm the human-like expression of exhaustion and senescence markers in a mouse model with a humanized immune system (HIS): the Balb/c Rag2KO IL2rgcKO SirpαNOD Flk2KO HLA-A2HHD (BRGSF-A2) mouse reconstituted with human CD34+ cord blood cells. With regard to senescence markers, the percentage of CD57+ T cells was higher in the bone marrow (BM) than in the spleen or blood. The same was true for KLRG1+ hCD8+ T cells. With regard to exhaustion markers, the percentage of programmed death 1 (PD-1+) T cells was higher in the BM than in the spleen or blood; the same was true for TIGIT+ hCD4+ cells. These tissue-specific differences were related to both higher proportions of memory T cells in BM and intrinsic differences in expression within the memory fraction. In blood samples from HIS mice and healthy human donors (HDs), we found that the percentage of KLRG1+ cells among hCD8+ T cells was lower in HIS compared to HDs. The opposite was true for CD4+ T cells. Unexpectedly, a high frequency of KLRG1+ cells was observed among naive T cells in HIS mice. CD57 expression on T cells was similar in blood samples from HIS mice and HDs. Likewise, PD-1 expression was similar in the two systems, although a relatively low proportion of HIS hCD4+ T cells expressed TIGIT. The BRGSF-A2 HIS mouse's exhaustion and senescence profile was tissue specific and relatively human like; hence, this mouse might be a valuable tool for determining the preclinical efficacy of immunotherapies.
Synthesis of [13C2,15N]‐1,3‐2H‐1‐benzyl‐(Z)‐3‐(benzylidene)indolin‐2‐one
Authors: Yang Jixia , Zhang Gongzheng , Wang Zhaoyang , Xiao Zhanxiong , Wen Hongliang
Published: August 2019

Parkinson disease (PD) is a neurodegenerative disorder characterized by the accumulation of α‐synuclein into Lewy bodies. 3‐Benzylidine‐indolin‐2‐one represents a class of compounds, which are known to inhibit the accumulation of α‐synuclein. In this paper, we report the synthesis of [13C] and [15N] labelled 1‐benzyl‐(Z)‐3‐(benzylidene)indolin‐2‐one from commercially available [13C2]‐chloroacetic acid and [15N]‐aniline in five steps. The product will be used to study its metabolites in human liver microsomes by liquid chromatography‐tandem mass spectrometry.
Stationary and non‐stationary detection of extreme precipitation events and trends of average precipitation from 1980 to 2010 in the Paraná River basin, Brazil
Authors: Xavier Ana Carolina Freitas , Rudke Anderson Paulo , Fujita Thais , Blain Gabriel Constantino , de Morais Marcos Vinicius Bueno , de Almeida Daniela Sanches , Rafee Sameh Adib Abou , Martins Leila Droprinchinski , de Souza Rodrigo Augusto Ferreira , de Freitas Edimilson Dias , Martins Jorge Alberto
Published: August 2019

The main objective of this study was to investigate the trends on average and extreme events in time series of daily precipitation from 1980 to 2010 in the Paraná River basin, Brazil. The nonparametric Mann–Kendall test was applied to detect monotonic trend in the precipitation series. The occurrence of extreme values was analysed based on three generalized extreme values (GEV) models: Model 1 (stationary), Model 2 (non‐stationary for location parameter), and Model 3 (non‐stationary for location and scale parameters). The GEV parameters were estimated by the Generalized Maximum Likelihood method (GMLE) and for the non‐stationary models, the parameters were estimated as linear functions of time. To choose the most suitable model, the maximum likelihood ratio test (D) was used. From the results observed at the monthly scale, it was possible to infer that the months with the highest probability of an extreme weather event occurrence are February (climates Aw and Cfa), July (Cfa and Cfb), and October (Aw, Cfa, and Cfb). Approximately 90% of the 1,112 stations presented no trend regarding the GEV parameters. The non‐stationarity showed by other stations (Models 2 and 3) might be associated with several factors, such as the alteration of land use due to the north expansion of the agricultural border of the Paraná River basin.
Elucidation of Interactions between l‐Ascorbic Acid and Mixed Micellar Aggregates of Catanionic {Sodium Dodecylsulfate + Cetyltrimethylammonium Bromide} Surfactants via Physicochemical and Spectroscopic Studies
Authors: Banipal Parampaul K. , Sohal Pallavi , Arti Sonika , Banipal Tarlok S.
Published: August 2019

Surfactant micelles mimic the microenvironment present in biological systems and can act as a medium for antioxidant studies. Moreover, the thermodynamic profile of micellization and spectroscopic studies provides very good information about interactions in these systems. Thus, the mixed micellar behavior of sodium dodecylsulfate (SDS) and cetyltrimethylammonium bromide (CTAB) at varying mole fractions of SDS was studied in (0.01, 0.02, and 0.03) mol kg−1 ʟ‐ascorbic acid(aq) solutions with the aid of various techniques viz., conductivity, density and sound velocity, and spectroscopy. From the CMC values of the mixed surfactants, the degree of ionization (β) and thermodynamic parameters (, , and ) were evaluated at 298.15, 308.15, and 318.15 K. The UV absorption spectra were recorded in (1–3) × 10−4 mol kg−1 ʟ‐ascorbic acid(aq) solutions at various mole fractions of SDS. The proton (1H) NMR spectra of mixed (SDS + CTAB) surfactants were studied in (0.01–0.03) mol kg−1 ʟ‐ascorbic acid solutions. Hydrodynamic diameters (Dh) of mixed micellar aggregates were obtained from the dynamic light scattering (DLS) studies. The present studies suggest the predominance of ionic‐hydrophilic interactions between the ionic head groups {O‐SO3− or N+ (CH3)3} of surfactants and the polar (–OH, –C=O and –O–) sites of ʟ‐ascorbic acid.
Prognostic Implications of a Point‐of‐Care Ultrasound Examination on Hospital Ward Admission
Authors: Kimura Bruce J. , Lou May M. , Dahms Eric B. , Han Paul J. , Waalen Jill
Published: August 2019

Objectives

Few data exist regarding the use of ultrasound (US) to risk stratify ward admissions. Therefore, we evaluated associations between a cardiopulmonary limited ultrasound examination (CLUE) on admission and subsequent hospital outcomes.

Methods

Over a 22‐month period in a 300‐bed hospital, CLUE data reviewed from a series of nonelective ward admissions were correlated with the composite outcome of a hospital stay of longer than 2 days, disposition to hospice, or death. The CLUE included 5 quick‐look signs of left ventricular dysfunction, left atrial enlargement, lung B‐lines, pleural effusions, and inferior vena cava plethora and had been performed as warranted by 1 of 31 US‐trained admitting residents and then repeated by a cardiologist as the reference standard. The admitting condition, medical history, results of routine admission testing, and CLUE were assessed for an association with the outcome in univariate and multivariable models.

Results

Of 547 patients, the mean age ± SD was 62.9 ± 15.5 years; 59% were male; and the mean stay was 5.6 ± 8.1 days, with 355 (65%) lasting longer than 2 days and 21 (4%) having hospice disposition or death. An abnormal CLUE exam was found in 368 (67%) of patients, was related to the outcome (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.23–2.68; P = .001) when obtained by a resident or cardiologist, and was included in a best‐fit multivariable model with renal failure (OR, 2.44; 95% CI, 1.44–4.14; P < .001), infection/sepsis (OR, 2.25; 95% CI, 1.17–4.32; P = .02), and chest pain (OR, 0.36; 95% CI, 0.21–0.61; P < .001).

Conclusions

An abnormal admission point of care ultrasound exam was related to complex hospitalization, specifically a longer length of stay.
Radiomics for the prediction of EGFR mutation subtypes in non‐small cell lung cancer
Authors: Li Shu , Ding Changwei , Zhang Hao , Song Jiangdian , Wu Lei
Published: August 2019

Purpose

This retrospective study was designed to investigate the ability of radiomics to predict the mutation status of epidermal growth factor receptor (EGFR) subtypes (19Del and L858R) in patients with non‐small cell lung cancer (NSCLC).

Methods

In total, 312 patients with NSCLC were included, and 580 radiomic features were extracted from the computed tomography images of each patient. In the training set, univariate analysis was performed on the clinical and radiomic features; logistic regression models were established using a 5‐fold cross validation strategy for the prediction of EGFR subtypes 19Del and L858R. Subsequently, the predictive ability of the joint models was evaluated using the test set.

Results

The results revealed that the radiomic features specific for EGFR 19Del and L858R were Gabor’s MTRVariance, Gabor’s PTREntropy, and sphericity. Additionally, the respective areas under the receiver operating characteristic curves of the EGFR 19Del and L858R joint models were 0.7925 and 0.7750 for the test set.

Conclusions

Our study demonstrated the potential for radiomics to predict EGFR 19Del and L858R. Epidermal growth factor receptor 19Del and L858R exhibited distinct imaging phenotypes, which may help to guide the selection of more accurate and personalized treatment programs for patients with NSCLC.
Technical Note: Monte Carlo methods to comprehensively evaluate the robustness of 4D treatments in proton therapy
Authors: Souris Kevin , Barragan Montero Ana , Janssens Guillaume , Di Perri Dario , Sterpin Edmond , Lee John A.
Published: August 2019

Introduction

Proton therapy is very sensitive to treatment uncertainties. These uncertainties can induce proton range variations and may lead to severe dose distortions. However, most commercial tools only offer a limited integration of these uncertainties during treatment planning. In order to verify the robustness of a treatment plan, this study aims at developing a comprehensive Monte Carlo simulation of the treatment delivery, including the simulation of setup and range errors, variation of the breathing motion, and interplay effect.

Method

Most clinically relevant uncertainties have been modeled and implemented in the fast Monte Carlo dose engine MCsquare. Especially, variation of the breathing motion is taken into account by deforming the initial Four‐dimensional computed tomography (4DCT) series and generating multiple new 4DCT series with scaled motion. Systematic and random errors are randomly sampled, following a Monte Carlo approach, to generate individual erroneous treatment scenarios. The robustness of treatment plans is analyzed and reported with dose‐volume histogram (DVH) bands. The statistical uncertainty coming from the Monte Carlo scenario sampling is studied.

Results

A validation demonstrated the ability of the motion model to generate new 4DCT series with scaled motion amplitude and improved image quality in comparison to the initial 4DCT. The robustness analysis is applied to a lung tumor treatment. Considering the proposed uncertainty model, the simulation of 300 treatment scenarios was necessary to reach an acceptable level of statistical uncertainty on the DVH band.

Conclusion

A comprehensive and statistically sound method of treatment plan robustness verification is proposed. The uncertainty model presented in this paper is not specific to protons and can also be applied to photon treatments. Moreover, the generated 4DCT series, with scaled motion, can be imported in commercial TPSs.
NMR characterization of rearranged staurosporine aglycone analogues from the marine sponge Damiria sp.
Authors: Tran Trong D. , Cartner Laura K. , Bokesch Heidi R. , Henrich Curtis J. , Wang Xin W. , Mahidol Chulabhorn , Ruchirawat Somsak , Kittakoop Prasat , O'Keefe Barry R. , Gustafson Kirk R.
Published: August 2019

The indolocarbazole family of bisindole alkaloids is best known for the natural product staurosporine, a protein kinase C inhibitor that belongs to the indolo[2,3‐a]carbazole structural class. A large number of other indolo[2,3‐a]carbazoles have subsequently been isolated and identified, but other isomeric forms of indolocarbazole natural products have rarely been reported. An extract of the marine sponge Damiria sp., which represents an understudied genus, provided two novel alkaloids named damirines A (1) and B (2). Their structures were assigned by comprehensive NMR spectroscopic analyses, and for compound 2, this included application of the LR‐HSQMBC pulse sequence, a long‐range heteronuclear correlation experiment that has particular utility for defining proton‐deficient scaffolds. The damirines represent a new hexacyclic carbon–nitrogen framework comprised of an indolo[3,2‐a]carbazole fused with either an aminoimidazole or a imidazolone ring. Compound 1 showed selective cytotoxic properties toward six different cell lines in the NCI‐60 cancer screen.
Save Energy With Anti‐Stagnation Valves
Authors: Alberton Dave , Sucharda Peter
Published: August 2019

The city of Hamilton's water distribution system is one of Canada's oldest and most complex water distribution systems. Situated at the west end of Lake Ontario, the city has an elevation of 298 ft (91 m) above sea level and is defined by unique geographical features, including the Niagara Escarpment and the Hamilton Harbor.
Protect Pipes Through Transient Control
Authors: Blake Michael
Published: August 2019

Water hammer is the leading cause of line breaks in water systems. Intelligent control systems can mitigate the effects of transients and protect pipelines from damage.
Spatial repellency, antifeedant activity and toxicity of three medium chain fatty acids and their methyl esters of coconut fatty acid against stable flies
Authors: Roh Gwang H , Zhou Xiaaojie , Wang Yansu , Cermak Steven C , Kenar James A , Lehmann Alexander , Han Baoyu , Taylor David B , Zeng Xiaopeng , Park Chung Gyoo , Brewer Gary J , Zhu Junwei J
Published: August 2019

BACKGROUND

Stable flies are one of the most detrimental arthropod pests to livestock. With changing climates and agronomic practices, they expand their roles as pests and disease vectors as well. Their painful bites reduce livestock productivity, annoy companion animals, and interfere with human recreational activities. Current management technologies are unable to effectively control stable flies. The present study reports new results concerning the contact, spatial repellency, and toxicity of a bio‐based product, coconut fatty acid and their methyl ester derivatives of free fatty acids of C8:0, C10:0 and C12:0 to stable flies.

RESULTS

Three medium chain fatty acid methyl esters (C8:0, C10:0 and C12:0) showed strong antifeedant activity against stable flies and their strengths were dose‐dependent. Only the C8:0 acid, C8:0‐ and C10:0 methyl esters elicited significant antennal responses. Laboratory single cage olfactometer bioassays revealed that coconut fatty acid and C8:0 methyl ester displayed active spatial repellency. All three methyl esters showed strong toxicity against stable flies.

CONCLUSION

Antifeedant activity is the main method through which coconut fatty acid deters stable fly blood‐feeding. The C8:0, C10:0 and C12:0 methyl esters act not only as strong antifeedants, but also possess strong toxicity against stable fly adults. Limited spatial repellency was observed from coconut fatty acid and C8:0 methyl ester. © 2019 Society of Chemical Industry
High Stability of Epitaxial Graphene on a SiC Substrate
Authors: Kujime Takaya , Taniguchi Yoshiaki , Akiyama Daiu , Kawamura Yusuke , Kanai Yasushi , Matsumoto Kazuhiko , Ohno Yasuhide , Nagase Masao
Published: August 2019

The effects of strong‐acid treatment on an epitaxial graphene film on a SiC substrate are investigated to confirm its stability and compatibility with conventional semiconductor device fabrication processes. An epitaxial graphene film is treated with a strong acid in the form of piranha solution (H2O2 + H2SO4), which is conventionally used in washing processes for the silicon‐based technology. Raman spectroscopy, Hall measurements, and contact angle measurements are carried out before and after piranha treatment. Raman mapping results show no drastic changes before and after piranha treatment. In particular, the D band is not observed after the piranha treatment. From Hall measurements, the electron mobility slightly increases from 920 to 1420 cm2 V−1 s−1 after five piranha treatments. The contact angle is almost constant before (72.8°) and after five piranha treatments (75.2°). These results indicate that the epitaxial graphene film is quite stable under piranha treatment.
Connected Reading: A Framework for Understanding How Adolescents Encounter, Evaluate, and Engage With Texts in the Digital Age
Authors: Turner Kristen Hawley , Hicks Troy , Zucker Lauren
Published: August 2019

Since the emergence of the World Wide Web and e‐reading devices in the late 1990s and early 2000s, reading research has focused on issues of website credibility, search and navigation strategies, and the ability to comprehend text on‐screen as compared with in print. What has been missing, however, are data about the specific texts that adolescents are reading in these digital spaces, what devices they prefer, and the strategies that they employ. Drawing from survey data (N = 804) and interviews (n = 23) with participants in grades 7–12 from 12 suburban, urban, and rural schools across the United States, the authors sought to explore what, where, and how adolescents read digitally. The authors propose a new framework of connected reading, a model of print and digital reading comprehension that conceptualizes readers’ interactions with digital texts through encountering (the ways in which readers seek or receive digital texts), evaluating (the ways in which readers make judgments about the usefulness of digital texts), and engaging (the ways in which readers interact with and share digital texts). In light of the findings, the authors argue that it is imperative to reframe discussions about how adolescents are taught to comprehend and interact with a variety of digital texts (e.g., webpages, e‐books, multimedia, social media).
Twin peaks
Authors: Burdzy Krzysztof , Pal Soumik
Published: August 2019

We study random labelings of graphs conditioned on a small number (typically one or two) peaks, that is, local maxima. We show that the boundaries of level sets of a random labeling of a square with a single peak have dimension 2, in a suitable asymptotic sense. The gradient line of a random labeling of a long ladder graph conditioned on a single peak consists mostly of straight line segments. We show that for some tree‐graphs, if a random labeling is conditioned on exactly two peaks then the peaks can be very close to each other. We also study random labelings of regular trees conditioned on having exactly two peaks. Our results suggest that the top peak is likely to be at the root and the second peak is equally likely, more or less, to be any vertex not adjacent to the root.
Ultrafast Photoinduced Electron Transfer from Cyclometalated Rhodium and Iridium Complexes to Cyan Emitting Copper Nanoclusters: Footsteps toward Light Harvesting
Authors: Bhunia Soumyadip , Seth Sourav Kanti , Gupta Parna , Karmakar Manobina , Datta Prasanta Kumar , Purkayastha Pradipta
Published: August 2019

In recent times, copper nanocluster (Cu NC) has become a promising candidate as an interesting nanomaterial for its potential applications in optoelectronics, sensing, catalysis and bioimaging. Herein, we have synthesized L–Cysteine protected Cu NC in 1:1 water:acetonitrile (ACN) solvent possessing bright cyan emission (λem=495 nm) with 10.4% quantum yield. Furthermore, the cyclometalated complexes of Ir(III) and Rh(III) are light harvesters, which are applied in photoinduced electron and energy transfer and photocatalysis. Three such cyclometalated complexes of Rh and Ir have been employed herein, which on electrostatic interaction with Cu NCs in 1:1 water:ACN medium, quench the fluorescence from Cu NC dramatically. This quenching could be suitably attributed to photoinduced electron transfer (PET) where Cu NC acts as an electron acceptor. PET has been confirmed by steady state and time resolved fluorescence spectroscopy as well as by ultrafast femtosecond upconversion and transient absorption spectroscopy.
Improved Thermal Cyclability of Tertiary Battery Made of Prussian Blue Analogues
Authors: Takahara Izumi , Shibata Takayuki , Fukuzumi Yuya , Moritomo Yutaka
Published: August 2019

Tertiary battery is charged by the environmental heat, not by the electric energy, by using the difference (Δα) in the thermal coefficient (α=dV/dT) of redox potential (V) between the anode and cathode materials. The thermal cyclability is not good in the prototypical NaxCo[Fe(CN)6]0.71 (NCF71)/NaxCo[Fe(CN)6]0.90 (NCF90) tertiary battery. Here, we significantly improved the thermal cyclability of the tertiary battery with using Ni‐substituted NaxNi[Fe(CN)6]0.68 (NNF68). The Ni‐substituted NNF68/NCF90 tertiary battery shows good thermal cyclability: both the cell voltage and capacity essentially unchanged up to the 10th thermal cycles.
Text mining in education
Authors: Ferreira‐Mello Rafael , André Máverick , Pinheiro Anderson , Costa Evandro , Romero Cristobal
Published: August 2019

The explosive growth of online education environments is generating a massive volume of data, specially in text format from forums, chats, social networks, assessments, essays, among others. It produces exciting challenges on how to mine text data in order to find useful knowledge for educational stakeholders. Despite the increasing number of educational applications of text mining published recently, we have not found any paper surveying them. In this line, this work presents a systematic overview of the current status of the Educational Text Mining field. Our final goal is to answer three main research questions: Which are the text mining techniques most used in educational environments? Which are the most used educational resources? And which are the main applications or educational goals? Finally, we outline the conclusions and the more interesting future trends.

This article is categorized under:

Application Areas > Education and Learning

Ensemble Methods > Text Mining
Influence of Elevated Temperatures on Mechanical Properties and Microstructure of C106 Copper Investigated by In Situ Heated Stage EBSD Analysis
Authors: Taylor S. , Masters I. , Li Z. , Kotadia H. R.
Published: August 2019

This study presents two analogs of extant industrial thermomechanical cycles to look at the microstructural evolution of C106 phosphorous deoxidized copper throughout. Vickers hardness testing was employed to assess the influence on post-formed mechanical properties. In situ heated stage EBSD analyses using a Carl Zeiss Sigma FEGSEM and Gatan Murano heated stage were employed to establish the temperature region where recrystallization initiates to better understand results from bulk post facto EBSD analysis.
A holistic engineering approach to aeronautical product development
Authors: Staack I. , Amadori K. , Jouannet C.
Published: August 2019

Product development, especially in aerospace, has become more and more interconnected with its operational environment. In a constant changing world, the operational environment will be subjected to changes during the life cycle of the product. The operational environment will be affected by not only technical and non-technical perturbations, but also economical, managerial and regulatory decisions, thus requiring a more global product development approach. One way to try tackling such complex and intertwined problem advocates studying the envisioned product or system in the context of system of systems (SoS) engineering. SoSs are all around us, probably in any field of engineering, ranging from integrated transport systems, public infrastructure systems to modern homes equipped with sensors and smart appliances; from cities filling with autonomous vehicle to defence systems.

Since also aerospace systems are certainly affected, this work will present a holistic approach to aerospace product development that tries spanning from needs to technology assessment. The proposed approach will be presented and analysed and key enablers and future research directions will be highlighted from an interdisciplinary point of view. Consideration of the surrounding world will require to look beyond classical engineering disciplines.