bluuebunny/crossref_metadata_2025 huggingface dataset:
Which one came first: movement behavior or frailty? A cross‐lagged panel model in the Toledo Study for Healthy Aging
Authors: Mañas Asier , del Pozo‐Cruz Borja , Rodríguez‐Gómez Irene , Losa‐Reyna José , Rodríguez‐Mañas Leocadio , García‐García Francisco J. , Ara Ignacio
Published: January 2020

Background

There has been limited longitudinal assessment of the relationship between moderate‐to‐vigorous physical activity (MVPA) and sedentary behaviour (SB) with frailty, and no studies have explored the possibility of reverse causality. This study aimed to determine the potential bidirectionality of the relationship between accelerometer‐assessed MVPA, SB, and frailty over time in older adults.

Methods

Participants were from the Toledo Study for Healthy Aging. We analysed 186 older people aged 67 to 90 (76.7 ± 3.9; 52.7% female participants) over a 4‐year period. Time spent in SB and MVPA was assessed by accelerometry. Frailty Trait Scale was used to determine frailty levels. A cross‐lagged panel model design was used to test the reciprocal relationships between MVPA/SB and frailty.

Results

Frailty Trait Scale score changed from 35.4 to 43.8 points between the two times (P < 0.05). We also found a reduction of 7 min/day in the time spent on MVPA (P < 0.05), and participants tended to spend more time on SB (P = 0.076). Our analyses revealed that lower levels of initial MVPA predicted higher levels of later frailty [std. β = −0.126; confidence interval (CI) = −0.231, −0.021; P < 0.05], whereas initial spent time on SB did not predict later frailty (std. β = −0.049; CI = −0.185, 0.087; P = 0.48). Conversely, an initial increased frailty status predicted higher levels of later SB (std. β = 0.167; CI = 0.026, 0.307; P < 0.05) but not those of MVPA (std. β = 0.071; CI = −0.033, 0.175; P = 0.18).

Conclusions

Our observations suggest that the relationship between MVPA/SB and frailty is unidirectional: individuals who spent less time on MVPA at baseline are more likely to increase their frailty score, and individuals who are more frail are more likely to spent more time on SB at follow‐up. Interventions and policies should aim to increase MVPA levels from earlier stages to promote successful aging.
Pyrite enhanced the reactivity of zero‐valent iron for reductive removal of dyes
Authors: Chen Kun , Han Linting , Li Jianfa , Lü Ying , Yao Chunxia , Dong Huaping , Wang Lijun , Li Yimin
Published: January 2020

BACKGROUND

Zero‐valent iron (ZVI) is an environmentally friendly and cost‐efficient material for the removal of contaminants. However, its application is challenged by problems such as surface passivation and pH increase in the reaction media. As a potential solution for this problem, pyrite, a waste of the mining industry, was used together with ZVI for reductive removal of azo dyes.

RESULTS

In comparison with ZVI alone, the ZVI/pyrite mixture showed dramatically enhanced efficiency and reusability for dye removal, although pyrite itself can hardly remove dyes. The reaction rate constant kobs for the removal of Orange II at the initial pH (pH0) of 7.0 was enhanced 9.4‐ to 28.0‐fold by using the mixture at a pyrite/ZVI mass ratio ranging from 1 to 4, respectively. The mechanism studies indicate that pyrite not only helped produce more iron(II) by facilitating iron corrosion and the iron(II)/iron(III) cycle in the mixed system, but also activated the ZVI surface by in situ sulfidation. The high reactivity of the adsorbed iron(II) in the mixed system significantly contributed to dye removal, especially at the alkalescent pH.

CONCLUSION

Pyrite accelerated the reductive removal of dyes by ZVI, through inhibiting its surface passivation and suppressing the pH increase in the reaction media. Therefore, this research proposes a facile method for enhancing the reactivity and applicability of ZVI in environmental remediation. © 2020 Society of Chemical Industry
Microalgae as biocatalyst in simultaneous photodegradation of antibiotics and hormones
Authors: Díaz‐Quiroz Carlos , Ulloa‐Mercado Gabriela , Hernández‐Chávez Juan Francisco , Rentería‐Mexía Ana , Serrano‐Palacios Denisse , Meza‐Escalante Edna
Published: January 2020

Background

Unregulated use of veterinary pharmaceuticals has caused environmental concerns such as ecotoxicity and development of genetic resistance in the microbial biosphere. Photocatalytic treatments, e.g. photo‐Fenton reaction, have been considered for their removal. In this work, substitution of the use of a chemical oxidant such as hydrogen peroxide (Fenton reaction) by organic molecules from sonicated microalgae biomass Chlorella sp, combined with Fe2+ and UV light, was used to evaluate the removal of antibiotic ciprofloxacin (CIP) and hormone 17β‐estradiol (E2) in synthetic wastewater.

Results

Removal of CIP was improved using only UV (71%), by adding Fe2+ at 0.54 mmol L−1 (90.17%) and combining these with sonicated microalgae biomass (0.4 g L−1), achieving >99% CIP removal and 75% E2 removal after 120 min of treatment. When the conditions were optimized, aiming to decrease the Fe2+ concentration and improve the removal of CIP, the optimal conditions were pH 7, sonicated microalgae biomass concentration 0.5 g L−1 and 0.39 mmol L−1 Fe2+, reaching 97 and 70% removal efficiency for CIP and E2 respectively; when microalgae biomass was not added, removal decreased to 90 and 57% respectively.

Conclusion

Photodegradation with sonicated microalgae biomass has demonstrated to be an effective option to improve the removal of selected antibiotics and hormones from wastewater, considering that no acidification or costly reagents are needed for its optimization. © 2020 Society of Chemical Industry
Bio‐electro‐Fenton systems for sustainable wastewater treatment: mechanisms, novel configurations, recent advances, LCA and challenges. An updated review
Authors: Li Shengnan , Hua Tao , Li Fengxiang , Zhou Qixing
Published: January 2020

Bio‐electro‐Fenton processes use biological electrons produced from bioelectrochemical systems to treat wastewater. The most significant advantages of bio‐electro‐Fenton systems are high effectiveness, low toxicity, gentle operation conditions, environmentally friendly treatment without sludge accumulation and energy conservation. Though promising, bio‐electro‐Fenton systems still face several challenges, such as high power density, H2O2 concentration, cathode materials, Fe2+ concentration and pH. This review comprehensively discusses the mechanisms of bio‐electro‐Fenton systems. Then, structural configurations are critically reviewed, including microbial fuel cells coupled with electro‐Fenton systems, microbial electrolysis cells coupled with electro‐Fenton systems and other bioelectrochemical systems coupled with electro‐Fenton systems. Furthermore, recent advances in bio‐electro‐Fenton systems for wastewater treatment are introduced, including dye solution, pharmaceuticals and personal care products, oily wastewater, landfill leachate and other pollutants. In addition, the current challenges and specific future prospects of bio‐electro‐Fenton, such as possible mechanisms for improving the power output, electrode materials that are potentially useful, self‐designed electrodes and methods of maintaining circumneutral pH values, are also explored. Heretofore, great progress in bio‐electro‐Fenton has been made, but further improvements are still needed in order to make this system more economical and practical. © 2020 Society of Chemical Industry
Micromorphology analysis of TiO2 thin films by atomic force microscopy images: The influence of postannealing
Authors: Ţălu Ştefan , Achour Amine , Solaymani Shahram , Nikpasand Kimia , Dalouji Vali , Sari Amirhossein , Rezaee Sahar , Nezafat Negin B.
Published: January 2020

This work describes an analysis of titanium dioxide (TiO2) thin films prepared on silicon substrates by direct current (DC) planar magnetron sputtering system in O2/Ar atmosphere in correlation with three‐dimensional (3D) surface characterization using atomic force microscopy (AFM). The samples were grown at temperatures 200, 300, and 400°C on silicon substrate using the same deposition time (30 min) and were distributed into four groups: Group I (as‐deposited samples), Group II (samples annealed at 200°C), Group III (samples annealed at 300°C), and Group IV (samples annealed at 400°C). AFM images with a size of 0.95 μm × 0.95 μm were recorded with a scanning resolution of 256 × 256 pixels. Stereometric analysis was carried out on the basis of AFM data, and the surface topography was described according to ISO 25178‐2:2012 and American Society of Mechanical Engineers (ASME) B46.1‐2009 standards. The maximum and minimum root mean square roughnesses were observed in surfaces of Group II (Sq = 7.96 ± 0.1 nm) and Group IV (Sq = 3.87 ± 0.1 nm), respectively.
The big reveal: Family disclosure patterns of BRCA genetic test results among young Black women with invasive breast cancer
Authors: Conley Claire C. , Ketcher Dana , Reblin Maija , Kasting Monica L. , Cragun Deborah , Kim Jongphil , Ashing Kimlin Tam , Knott Cheryl L. , Hughes‐Halbert Chanita , Pal Tuya , Vadaparampil Susan T.
Published: January 2020

Despite higher incidence and mortality of breast cancer among younger Black women, genetic testing outcomes remain severely understudied among Blacks. Past research on disclosure of genetic testing results to family members has disproportionately focused on White, educated, high socioeconomic status women. This study addresses this gap in knowledge by assessing (a) to whom Black women disclose genetic test results and (b) if patterns of disclosure vary based on test result (e.g., BRCA1/2 positive, negative, variant of uncertain significance [VUS]). Black women (N = 149) with invasive breast cancer diagnosed age ≤50 years from 2009 to 2012 received free genetic testing through a prospective, population‐based study. At 12 months post‐testing, women reported with whom they shared their genetic test results. The exact test by binomial distribution was used to examine whether disclosure to female relatives was significantly greater than disclosure to male relatives, and logistic regression analyses tested for differences in disclosure to any female relative, any male relative, parents, siblings, children, and spouses by genetic test result. Most (77%) women disclosed their results to at least one family member. Disclosure to female relatives was significantly greater than disclosure to males (p < .001). Compared to those who tested negative or had a VUS, BRCA1/2‐positive women were significantly less likely to disclose results to their daughters (ORBRCA positive = 0.25, 95% CI = 0.07–0.94, p = .041) by 12 months post‐genetic testing. Genetic test result did not predict any other type of disclosure (all ps > 0.12). Results suggest that in Black families, one benefit of genetic testing—to inform patients and their family about cancer risk information—is not being realized. To increase breast cancer preventive care among high‐risk Black women, the oncology care team should prepare Black BRCA1/2‐positive women to share genetic test results with family members and, in particular, their daughters.
Emerging evidence from a systematic review of safety of pre‐exposure prophylaxis for pregnant and postpartum women: where are we now and where are we heading?
Authors: Joseph Davey Dvora L , Pintye Jillian , Baeten Jared M , Aldrovandi Grace , Baggaley Rachel , Bekker Linda‐Gail , Celum Connie , Chi Benjamin H , Coates Thomas J , Haberer Jessica E , Heffron Renee , Kinuthia John , Matthews Lynn T , McIntyre James , Moodley Dhayendre , Mofenson Lynne M , Mugo Nelly , Myer Landon , Mujugira Andrew , Shoptaw Steven , Stranix‐Chibanda Lynda , John‐Stewart Grace ,   for the PrEP in Pregnancy Working Group
Published: January 2020

Introduction

HIV incidence is high during pregnancy and breastfeeding with HIV acquisition risk more than doubling during pregnancy and the postpartum period compared to when women are not pregnant. The World Health Organization recommends offering pre‐exposure prophylaxis (PrEP) to pregnant and postpartum women at substantial risk of HIV infection. However, maternal PrEP national guidelines differ and most countries with high maternal HIV incidence are not offering PrEP. We conducted a systematic review of recent research on PrEP safety in pregnancy to inform national policy and rollout.

Methods

We used a standard Preferred Reporting Items for Systematic Reviews and Meta‐Analysis (PRISMA) approach to conduct a systematic review by searching for completed, ongoing, or planned PrEP in pregnancy projects or studies from clinicaltrials.gov, PubMed and NIH RePORTER from 2014 to March 2019. We performed a systematic review of studies that assess tenofovir disoproxil fumarate (TDF)‐based oral PrEP safety in pregnant and breastfeeding HIV‐uninfected women.

Results and discussion

We identified 14 completed (n = 5) and ongoing/planned (n = 9) studies that evaluate maternal and/or infant outcomes following PrEP exposure during pregnancy or breastfeeding. None of the completed studies found differences in pregnancy or perinatal outcomes associated with PrEP exposure. Nine ongoing studies, to be completed by 2022, will provide data on >6200 additional PrEP‐exposed pregnancies and assess perinatal, infant growth and bone health outcomes, expanding by sixfold the data on PrEP safety in pregnancy. Research gaps include limited data on (1) accurately measured PrEP exposure within maternal and infant populations including drug levels needed for maternal protection; (2) uncommon perinatal outcomes (e.g. congenital anomalies); (3) infant outcomes such as bone growth beyond one year following PrEP exposure; (4) outcomes in HIV‐uninfected women who use PrEP during pregnancy and/or lactation.

Conclusions

Expanding delivery of PrEP is an essential strategy to reduce HIV incidence in pregnancy and breastfeeding women. Early safety studies of PrEP among pregnant women without HIV infection are reassuring and ongoing/planned studies will contribute extensive new data to bolster the safety profile of PrEP use in pregnancy. However, addressing research gaps is essential to expanding PrEP delivery for women in the context of pregnancy.
Variation of the T‐wave peak‐end interval and heart rate variability values in healthy males and females at various hours of the same day, and relationship of them
Authors: Cosgun Ayhan , Oren Huseyin
Published: January 2020

Background

The prolongation of repolarization time between the myocardial epicardium and endocardial cells is closely related to malignant ventricular arrhythmias. The purpose of our study was to compare repolarization markers, namely, T‐wave peak‐end interval (Tp‐e), QT, corrected QT (QTc), Tp‐e/QT, Tp‐e/corrected QT (QTc), and Heart Rate Variability (HRV) values in healthy men and women and to investigate their daily variations.

Methods

A total of 74 male and 78 female participants, being a government employee, and having no health problems, were included in the two study groups (males and females). A 24‐hour, 12‐lead Holter monitoring was performed on the volunteers. Then, the Tp‐e interval and QT interval were measured on recordings. cTp‐e and QTc were calculated by the use of Bazzet's formula.

Results

There was no statistically significant difference between the groups in the cTp‐e interval at 07.00 pm; however, it was significantly lower in the female group as compared with the male group at 07.00 am and 01.00 pm. It was significantly higher in the female group at 01.00 am compared with the male group. There were statistically significant moderate negative correlations between Tp‐e intervals and a standard deviation of between two normal beats interval (SDNN) values at various hours of the same day.

Conclusion

There were statistically significant differences in terms of Tp‐e and cTp‐e intervals at various hours of the same day in both groups. In addition, there were statistically significant moderate negative correlations between Tp‐e intervals and SDNN at various hours of the same day.
Effect of cadmium on mRNA mistranslation in Saccharomyces cerevisiae
Authors: Zhang Xiaoyu , Kuang Xin , Cao Fangqi , Chen Ranran , Fang Zhijia , Liu Wenbin , Shi Ping , Wang Handong , Shen Yuhu , Huang Zhiwei
Published: January 2020

Although highly accurate molecular processes and various messenger RNA (mRNA) quality control and ribosome proofreading mechanisms are used by organisms to transcribe their genes and maintain the fidelity of genetic information, errors are inherent in all biological systems. Low‐level translation errors caused by an imbalance of homologous and nonhomologous amino acids caused by stress conditions are particularly common. Paradoxically, advantageous phenotypic diversity can be generated by such errors in eukaryotes through unknown molecular processes. Here, we found that the significant cadmium‐resistant phenotype was correlated with an increased mistranslation rate of the mRNA in Saccharomyces cerevisiae. This phenotypic change was also related to endogenous sulfur amino acid starvation. Compared with the control, the mistranslation rate caused by cadmium was significantly increased (p < .01). With the increase of cysteine contents in medium, the mistranslation rate of WT(BY4742a) decreased significantly (p < .01). This demonstrates that cadmium treatment and sulfur amino acid starvation both can induce translation errors. Although cadmium uptake is independent of the Sul1 transporter, cadmium‐induced mRNA mistranslation is dependent on the sulfate uptake of the Sul1p transporter. Furthermore, cadmium‐induced translation errors depend on methionine biosynthesis. Taken together, cadmium causes endogenous sulfur starvation, leading to an increase in the mRNA mistranslation, which contributes to the resistance of yeast cells to cadmium. We provide a new pathway mediating the toxicity of cadmium, and we propose that altering mRNA mistranslation may portray a different form of environmental adaptation.
Evaluation of salivary and serum asymmetric dimethylarginine (ADMA) levels in patients with periodontal and cardiovascular disease as subclinical marker of cardiovascular risk
Authors: Isola Gaetano , Alibrandi Angela , Currò Monica , Matarese Marco , Ricca Sergio , Matarese Giovanni , Ientile Riccardo , Kocher Thomas
Published: January 2020

Background

Asymmetric dimethylarginine (ADMA) plays a crucial role in endothelial function and maybe a link for the known interaction of periodontitis and coronary heart disease (CHD). In this pilot study, we compared the impact of gingival health, periodontitis (CP), CHD, or of both diseases (CP + CHD) on salivary and serum ADMA levels.

Methods

The clinical and periodontal characteristics, serum, and saliva samples were collected from 35 patients with CP, 33 patients with CHD, 35 patients with both CP + CHD, and 35 healthy subjects. Levels of ADMA and C‐reactive protein (CRP) were assessed with a commercially available kit.

Results

The median (25% and 75% percentile) concentrations of salivary and serum ADMA were significantly higher in the CHD group [serum: 1.5 (1.2 to 1.8) μmol/L; salivary 1.3 (1 to 1.7) μmol/g protein, P < 0.01] and in the CP + CHD [serum: 1.8 (1.4 to 2.0) μmol/L; salivary 1.5 (1.2 to 1.7) μmol/g protein, P < 0.001] group compared to CP patients and controls. In univariate models, CP (P = 0.034), CHD (P < 0.001), and hs‐CRP (P < 0.001) were significantly associated with serum ADMA, whereas in a multivariate model, hs‐CRP remained a significant predictor of serum ADMA (P < 0.001). In a multivariate model, the significant predictors of salivary ADMA levels were hs‐CRP (P < 0.001) and education socioeconomic status (P = 0.042).

Conclusions

Patients with CHD and CP + CHD presented higher levels of salivary and serum ADMA compared to healthy subjects and CP patients. hs‐CRP was a significant predictor of increased salivary and serum ADMA levels.
Robotic approach as a valid strategy to improve the access to posterosuperior hepatic segments—Case series and review of literature
Authors: Araujo Raphael L. C. , Sanctis Marco Aurelio , Barroti Lucas C. , Coelho Tomás R. V.
Published: January 2020

Introduction

Although the laparoscopy liver resection (LLR) has become a useful approach for minor resections, it seems that lesions in posterosuperior (PS) segments still represent technical challenges. We report a series of robotic approach as an alternative option for these lesions, and a systematic review of the literature to show its feasibility.

Methods

Consecutive patients who underwent liver resection for solitary lesions in PS segments by da Vinci SI robot, and by the same team. A systematic review of the literature was made to evaluate the feasibility of a robotic approach for PS hepatectomies.

Results

From April 2016 to April 2017, five cases of robotic nonanatomical PS resections of colorectal liver metastases (CRLM) were performed. A systematic review encountered five articles plus this series reporting outcomes for this approach. Briefly, a total of five patients in our series underwent this approach, all females, and one patient presented a grade 2 complication.

Conclusion

Robotic hepatectomy seems to be a useful and valid strategy to resect lesions on PS hepatic segments simplifying liver‐sparing hepatectomies. Even though the operative time is still high, the short length of stay, low number of complications and the low need for blood transfusions seems to surpass the intrinsic cost of robotic surgery.
Bark Beetle‐Affected Forests Provide Elk Only a Marginal Refuge from Hunters
Authors: Lamont Bryan G. , Kauffman Matthew J. , Merkle Jerod A. , Mong Tony W. , Hayes Matthew M. , Monteith Kevin L.
Published: January 2020

For nearly 2 decades, the forests of the Rocky Mountains in the United States experienced a bark‐beetle (Dendoctronus ponderosae) epidemic. The number of dead and falling trees from this epidemic likely will affect how elk (Cervus canadensis) and hunters use the forest and their interactions. Downed trees potentially create a component of refuge habitat that could affect the effectiveness of hunting to regulate abundance of growing elk populations. We evaluated how forests affected by bark beetles in south‐central Wyoming, USA, influenced resource selection of 50 female elk and 374 hunters in 2012–2016, and interactions between elk and hunters. We employed global positioning system (GPS) technology on elk and hunters, and developed a satellite‐derived land classification specifically depicting beetle‐affected forests. We tested the predictions that elk would increase use of beetle‐killed areas from summer to the hunting season, and that hunters would avoid beetle‐killed areas regardless of elk use. Elk increased use of beetle‐killed areas during hunting seasons as did hunters during the archery season; however, during the rifle season, hunters avoided beetle‐killed areas. Nevertheless, during the rifle season, areas of beetle‐kill with a high probability of elk occurrence dampened the aversion hunters had towards beetle‐killed areas. Therefore, in contrast to our expectations, forests that have been altered by the bark‐beetle epidemic may only function marginally as a refuge for elk. Our study area was at the beginning of the tree‐fall phase (i.e., ~3–7 yr after peak infestation) of the bark‐beetle epidemic; thus, future research efforts should focus on how a continued increase in downed trees will influence interactions between elk and hunters. At current levels of tree fall, however, beetle‐kill should not limit the ability of managers to regulate elk herds through harvest. © 2020 The Wildlife Society.
Effect of margin status and pathological grade in treatment of sinonasal mucoepidermoid carcinoma
Authors: Auger Samuel R. , Patel Tirth , Ganti Ashwin , Raman Anish , Shay Aryan , Kuhar Hannah N. , Kuan Edward C. , Papagiannopoulos Peter , Batra Pete S. , Tajudeen Bobby A.
Published: January 2020

Objectives

The purpose of this study was to investigate the association of demographic factors, grade, margin status, and treatment modalities for overall survival in patients with sinonasal mucoepidermoid carcinoma (SNMEC).

Study Design

Retrospective database review.

Methods

The National Cancer Database was queried for patients of all ages with SNMEC between 2004 and 2015. Univariate Kaplan‐Meier and multivariate Cox regression analyses were performed to evaluate the association of suspected prognostic factors with overall survival. Subgroup analysis by margin status and grade was performed.

Results

A total of 239 patients with SNMEC were included in the analysis. The 5‐year overall survival was 63.6%. Prognostic factors associated with decreased survival include age over 70 years (P = .027), sphenoid primary site (P = .002), and advanced‐stage malignancy (P = .024). Improved survival was associated with surgery achieving negative margins (P = .001). Adjuvant radiation was associated with improved survival (hazard ratio [HR] = 0.25, P = .015) in the negative‐margin group but was not found to be a statistically significant factor in the positive‐margin group (HR = 0.66, P = .509).

Conclusions

This investigation is the largest to date to analyze the association of treatment modalities with overall survival in SNMEC and subgroup analysis by histopathologic grade and surgical margin status of treatment outcomes. Surgery remains the mainstay of treatment in patients with SNMEC. However, administration of radiation may confer survival benefit to patients with negative margins.

Level of Evidence

4 Laryngoscope, 2020
Suppression of amino acid and oligopeptide mineralization by organic manure addition in a semiarid environment
Authors: Iqbal Shahid , Jones Davey L. , Arif Muhammad Saleem , Yasmeen Tahira , Xu Jianchu , Khan Sehroon , Nadir Sadia
Published: January 2020

The rapid mineralization of organic nitrogen (ON) in semiarid soils frequently results in large N losses, reduced crop yields, and environmental pollution. The addition of manures to soil has the potential to promote microbial growth, increase N immobilization, reverse the decline in soil organic matter, and enhance soil quality. In this study, three contrasting organic manures were used to determine their influences on amino acid and oligopeptide dynamics in soil (as key component of the soil ON‐cycle) as well their effects on the size of the microbial biomass and N immobilization. Laboratory incubation experiments were set up with soil obtained from experimental field trial sites for growing maize. Treatments included soil amended with either poultry manure (PM), farmyard manure, pressmud, or unamended (control). Radio‐ and stable‐isotope (14C–15N) techniques were used to assess ON mineralization, immobilization, and leaching using the amino acids alanine and valine as well as the oligopeptides trialanine and valine–proline–proline as model substrates. Quantitative polymerase chain reaction was used to determine soil bacterial biomass. The results showed that all manures increased microbial growth and total soil amino acids as well as protein content. Greater immobilization and subsequently lower mineralization and leaching were also observed in the manure‐amended soils, with this being most pronounced in the PM treatment. The application of PM also enhanced the half‐lives of the ON compounds in soil and increased the size of the bacterial biomass. Overall, our findings indicate that manure amendments, particularly PM, can help promote more efficient ON cycling in semi‐arid ecosystem by controlling N mineralization, reducing amino acid leaching, and elevating oligopeptide immobilization.
Trophic transfer of microplastics in an estuarine food chain and the effects of a sorbed legacy pollutant
Authors: Athey Samantha N. , Albotra Samantha D. , Gordon Cessely A. , Monteleone Bonnie , Seaton Pamela , Andrady Anthony L. , Taylor Alison R. , Brander Susanne M.
Published: January 2020

Microplastics are of increasing concern as they are readily ingested by aquatic organisms. This study investigated microplastic trophic transfer using larval inland silversides (Menidia beryllina) (5 d posthatch) and unicellular tintinnid (Favella spp.) as a model food chain relevant to North American estuaries. Low‐density polyethylene microspheres (10–20 μm) were used to compare direct ingestion of microplastics by larval fish and trophic transfer via tintinnid prey. Dichlorodiphenyltrichloroethane (DDT)‐treated microspheres were used to determine sorbed pollutant effects on microplastic ingestion. Larval fish exposed directly to microspheres ingested significantly fewer than those exposed via contaminated prey. Larvae ingested significantly more ciliates containing DDT‐treated microspheres than ciliates containing untreated plastics but did not discriminate when exposed directly. Larvae reared for 16 d following a direct 2 h exposure had significantly lower wet weight values than unexposed controls. Our results demonstrate that trophic transfer is a significant route of microplastic exposure that can cause detrimental effects in sensitive life stages.
An experimental investigation of the corrosive influence of SO2 relative to H2SO4 of marine engine cylinder liners
Authors: Kjemtrup Lars , Cordtz Rasmus F. , Jensen Michael V. , Schramm Jesper
Published: January 2020

The present study investigates the corrosive influence of SO2 on cylinder liner wear relative to H2SO4. Several charge gases with different concentrations of SO2, H2SO4, and H2O in air are fed to a motored light duty test engine that operates at 98 revolutions per minute (rpm) in order to resemble the corrosive combustion gas and cycle speed of large low‐speed two‐stroke marine engines. When the trapped cylinder gas is compressed, the H2SO4 and H2O vapours can condense on the oil wetted liner surface, and the SO2 can be absorbed in the oil film. Hereby the liner surface may be exposed to a corrosive attack. A blend of a base oil and a commercial marine engine cylinder lubrication oil is used in the experiments. During testing, oil samples are extracted from the engine and subsequently analysed for iron and sulphur accumulation (using an energy dispersive X‐ray fluorescence spectrometer) in order to couple cylinder liner wear with the amount of SO2, H2SO4, and H2O in the charge gas. In contrast to H2SO4, the wear of SO2 is weak (if any), although the SO2 accumulates/reacts considerably in the lube oil. The highest wear rates are found at elevated H2O concentrations.
OSpaad: An online tool to perform survival analysis by integrating gene expression profiling and long‐term follow‐up data of 1319 pancreatic carcinoma patients
Authors: Zhang Guosen , Wang Qiang , Yang Mengsi , Yao Xitong , Qi Xinlei , An Yang , Dong Huan , Zhang Lu , Zhu Wan , Li Yongqiang , Guo Xiangqian
Published: January 2020

Pancreatic carcinoma (PC) is a type of highly lethal malignant tumor that has unfavorable outcomes. One major challenge in improving clinical outcomes is to identify novel biomarkers for prognosis. In this study, we developed an online consensus survival tool for pancreatic adenocarcinoma (OSpaad), which allows researchers and clinicians to analyze the prognostic value of selected genes in PC. OSpaad contains 1319 unique PC cases that have both gene expression data and correspondent clinical data from seven individual cohorts and provides four survival terms including overall survival, disease‐specific survival, disease‐free interval, progression‐free interval for prognosis evaluation. To meet the different research needs, OSpaad allows users to limit survival analysis in subgroups by selecting different terms of clinical confounding factors such as TNM stage, sex, smoking time, lymph invasion, and race. Moreover, we showed that 97% (116 out of 120) previously reported prognostic biomarkers, including ERBB2, TP53, EGFR and so forth, were validated and confirmed their prognostic significance in OSpaad, demonstrating the well performance of survival analysis in OSpaad. OSpaad is a user‐friendly online tool with a straightforward interface allowing clinicians and basic research scientists with even a limited bioinformatics background to easily screen and evaluate the prognostic value of genes in a large PC cohort. This online tool can be accessed at http://bioinfo.henu.edu.cn/PAAD/PAADList.jsp.
Decreased Penetrance of Parkinson's Disease in Elderly Carriers of Glucocerebrosidase Gene L444P/R Mutations: A Community‐Based 10‐Year Longitudinal Study
Authors: Ji Shaozhen , Wang Chaodong , Qiao Hongwen , Gu Zhuqin , Gan‐Or Ziv , Fon Edward A. , Chan Piu
Published: January 2020

Background

Heterozygous mutations in the glucocerebrosidase gene (GBA) have been shown to be an important genetic risk factor for Parkinson's disease (PD) worldwide. However, the penetrance of GBA heterozygote for L444P, the common mutation for Asian population, is not known in older Chinese people.

Objectives

To assess the conversion rate to PD in identified carriers of GBA L444P/R mutations in Chinese community‐dwelling older adults.

Methods

The GBA gene was sequenced for mutations at position 444 in 8405 people older than 55 years who participated in the Beijing Longitudinal Study on Aging II cohort. Nine subjects were identified as heterozygous carriers of GBA L444P or L444R mutations at baseline and clinically followed up from 2009 to 2019 to investigate their PD conversion, motor and nonmotor symptoms, and change of vesicular monoamine transporter type 2 using tracer of [18F]9‐fluoropropyl‐(+)‐dihydrotetrabenazine (18F‐DTBZ, also known as 18F‐AV‐133).

Results

Eight heterozygous GBA L444P and 1 L444R mutation carriers were identified without PD at baseline, and none of them developed clinical parkinsonism after a 10‐year follow‐up.

Conclusions

Although GBA mutations may lead to an earlier onset PD, the majority of GBA L444P heterozygotes in older adults may not convert to PD. Further studies are warranted to identify factors that modify the risk of conversion. © 2020 International Parkinson and Movement Disorder Society
Performance evaluation of sub‐daily ensemble precipitation forecasts
Authors: Saedi Adeleh , Saghafian Bahram , Moazami Saber , Aminyavari Saleh
Published: January 2020

Nowadays, major advances have been made in meteorological forecasts. For instance, ensemble forecast systems have been developed to quantify prediction uncertainty. In this research, sub‐daily ensemble precipitation forecasts of five THORPEX Interactive Grand Global Ensemble (TIGGE) models from 2014 to 2018 were evaluated in 10 major basins located in north and west Iran. Furthermore, Bayesian model averaging (BMA) was used to combine five prediction models and construct a grand ensemble. The results indicate that the models had the best performance in the Karun and Western Border basins to the southwest and west, with average performance in the Sefidrood basin in the north. In terms of the prediction of precipitation depth, the European Centre for Medium‐Range Weather Forecasts (ECMWF) and the UK Met Office (UKMO) models, and in terms of prediction of precipitation occurrence and non‐occurrence, the National Centers for Environmental Prediction (NCEP) model, performed best. Overall, the Japan Meteorological Agency (JMA) and the China Meteorological Administration (CMA) models acquired medium scores. The BMA technique greatly improved the probability forecasts, reducing uncertainties in the numerical models. Moreover, the models’ forecasts were weaker with a 6 hr lead time compared with those with 24 hr, which may be attributable to the inaccurate detection of the initiation time of precipitation by the models. In addition, the performance of the UKMO (ECMWF) models with increasing basin elevation increased (decreased), while all models better forecasted precipitation in wet years/seasons than they did in dry years/seasons. Overall, the evaluations showed that the ECMWF, UKMO and NCEP models performed well in the majority of the northern and western basins of Iran.
Uncertainties in retrieving microphysical properties of rain profiles using ground‐based dual‐frequency radar
Authors: Wang Gaili , Liu Shengnan , Liu Liping
Published: January 2020

Dual‐frequency radar (DFR) could improve the accuracy of estimating the microphysical properties of rain profiles. Unfortunately, factors that cause inaccuracies in retrieved rain profiles include uncertainties in raindrop size distribution (DSD) parameterizations, DFR retrieval methods and radar measurement errors. The primary objective of this study was to assess the uncertainties in retrieving rain profiles to offer insight into application considerations for ground‐based DFRs in China. The uncertainties caused by DSD models are assessed by comparing attenuation coefficients and rain rates from DFR algorithms with those directly derived from DSD spectra from disdrometers. Then, based on a DSD model, the impacts of retrieval methods, radar range resolution, measurement error and errors in temperature on DFR retrievals are explored by comparing the rain profiles obtained using DFR algorithms with those directly output from the Weather Research and Forecasting model. Overall, the impact of measurement error on the DFR retrievals is relatively significant for both the forward retrieval method and the iterative backward retrieval method and should be eliminated in practical applications. At an individual uncertainty level, the impact of DSD parameterizations on the retrievals from the dual‐frequency technique is less than ±10% bias when the shape factor μ of the gamma distribution ranges from 2 to 4. The retrieved rain profiles from the forward retrieval method are relatively sensitive to radar range resolution and the retrieval performance can be improved with increasing the range resolution, while the iterative backward retrieval method exhibits stable retrieval performance. The impact of temperature errors on the retrieved rain profiles is negligible.
Mapping and monitoring of glacier lake outburst floods using geospatial modelling approach for Darkut valley, Pakistan
Authors: Amin Muhammad , Bano Dilshad , Hassan Sher S. , Goheer Muhammad A. , Khan Aftab A. , Khan Mobushir R. , Hina Syeda M.
Published: January 2020

Climate change and human activities have resulted in the receding of glaciers throughout the world including Pakistan. Glacier lake outburst floods (GLOFs) are amongst the most common climate‐change‐induced hazards in northern Pakistan. In the present study, GLOF mapping and modelling was carried out using remote sensing and geographical information system techniques coupled with ground‐truthing. Change detection techniques such as the normalized difference water index were applied on Landsat imagery for the identification of the temporal behaviour of Darkut glacial lake for the last 25 years. The depth of the lake was estimated to be 81 m and the volume of the lake was calculated using a digital terrain model and extracted as 9.79 × 106 m3. The glacial lake extent has increased from 0.045 to 0.154 km2 in the last two decades. Two GLOF scenarios (peak and extreme flood) were developed on an existing volume of water in the study. There are 14 households exposed to medium flood and 10 to low flood risk while one helipad and one school are also in the low flood zone in the first scenario (i.e. peak flood) based on 87.84 m3·s−1 of water. The second scenario (i.e. extreme flood) was executed on 3,128 m3·s−1 of water, in which 14 households are at high flood risk, eight at medium and 35 in a low flood zone, as well as one school, a helipad and a community stockpile which are exposed to low flood. The outcomes of the study will help in the development of risk management plans, preparedness strategies and risk reduction from GLOF hazard.
Air quality in the Galapagos Islands: A baseline view from remote sensing and in situ measurements
Authors: Cazorla María , Herrera Edgar
Published: January 2020

A characterization of ambient air levels of PM2.5, O3, SO2, NO2 and CO in the Galapagos Islands of Ecuador is presented from in situ and remote sensing observations. PM2.5 was derived from aerosol optical depth (AOD; AERONET) measured at the Universidad San Francisco de Quito, Galapagos Campus (2017–2019). Boundary layer (BL) ozone was obtained from Southern Hemisphere Additional Ozonesondes (SHADOZ) profiles (1998–2016). Background SO2 and pollution events during volcanic eruptions (2005–2018) were estimated from Ozone Monitoring Instrument (OMI) total column measurements through a well‐mixed volume approach. Similarly, ambient NO2 was estimated from OMI data (2012–2019). CO was obtained from Measurement Of Pollution In The Troposphere (MOPITT) observations (2012–2017). The study was complemented using Modern‐Era Retrospective Analysis for Research and Applications (MERRA‐2) reanalysis products and backward trajectory model runs. From the results, baseline levels of the analysed species (PM2.5 = 3.8 μg·m−3, O3 = 17 ppbv, SO2 = 3.6 ppbv, CO = 80 ppbv, NO2 in populated islands = 23 pptv as one year averages) are comparable with other pristine regions, but some factors can cause increased concentrations. First, high tourism seasons (February–April and July–September) raise background PM2.5, NO2 and CO. Furthermore, signals in July–September can be augmented by transport from biomass‐burning regions in the Amazon. This latter factor episodically causes ozone to increase up to 45–75 ppbv (1 hr mean). Lastly, volcanic eruptions raise SO2 up to almost 700 ppbv (24 hr mean) and increase PM2.5 to 29.5 μg·m−3 (1 hr mean). The present study provides for the first time baseline levels of air contaminants in the Galapagos, and identifies specific sources whose effect in time is necessary to monitor given global conditions of vulnerable environmental quality.
Developing nonuniform sampling strategies to improve sensitivity and resolution in 1,1‐ADEQUATE experiments
Authors: Roginkin Mark S. , Ndukwe Ikenna E. , Craft D. Levi , Williamson R. Thomas , Reibarkh Mikhail , Martin Gary E. , Rovnyak David
Published: January 2020

Nonuniform sampling (NUS) strategies are developed for acquiring highly resolved 1,1‐ADEQUATE spectra, in both conventional and homodecoupled (HD) variants with improved sensitivity. Specifically, the quantile‐directed and Poisson gap methods were critically compared for distributing the samples nonuniformly, and the quantile schedules were further optimized for weighting. Both maximum entropy and iterative soft thresholding spectral estimation algorithms were evaluated. All NUS approaches were robust when the degree of data reduction is moderate, on the order of a 50% reduction of sampling points. Further sampling reduction by NUS is facilitated by using weighted schedules designed by the quantile method, which also suppresses sampling noise well. Seed independence and the ability to specify the sample weighting in quantile scheduling are important in optimizing NUS for 1,1‐ADEQUATE data acquisition. Using NUS yields an improvement in sensitivity, while also making longer evolution times accessible that would be difficult or impractical to attain by uniform sampling. Theoretical predictions for the sensitivity enhancements in these experiments are in the range of 5–20%; NUS is shown to disambiguate weak signals, reveal some nJCC correlations obscured by noise, and improve signal strength relative to uniform sampling in the same experimental time. This work presents sample schedule development for applying NUS to challenging experiments. The schedules developed here are made available for general use and should facilitate the broader utilization of ADEQUATE experiments (including 1,1‐, 1,n‐, and HD‐ variants) for challenging structure elucidation problems.
Reconstruction of spectra from truncated free induction decays by deep learning in proton magnetic resonance spectroscopy
Authors: Lee Hyochul , Lee Hyeong Hun , Kim Hyeonjin
Published: January 2020

Purpose

To explore the applicability of convolutional neural networks (CNNs) in the reconstruction of spectra from truncated FIDs (tFIDs) in 1H‐MRS, which can be valuable in situations in which data sampling is highly limited, such as spectroscopic magnetic resonance fingerprinting.

Methods

Rat brain FIDs were simulated at 9.4 T based on in vivo data (N = 11) and randomly truncated by retaining 8, 16, 32, 64, 128, 256, 512, and 1024 (null truncation) points (denoted as tFID8, tFID16, … tFID1024). Using a U‐net, 3 CNNs were individually trained (N = 40 000) in time domain only (FID to FID [FIDCNNFID]), in frequency domain only (spectrum to spectrum [specCNNspec]), and across the domains (FID to spectrum [FIDCNNspec]) to map the truncated data to their fully sampled versions. The CNNs were tested on the simulated data (N = 5000), and the CNN with the best performance was further tested on the in vivo data, for which the CNN‐predicted fully sampled data were analyzed using the LCModel and the results were compared with those from the original, fully sampled data.

Results

The best result on the simulated data was obtained with specCNNspec, which effectively recovered the spectral details even for those input spectra that appear as a hump due to substantial FID truncation (spectra from tFID16 and tFID32). Overall, its performance was significantly degraded on the in vivo data. Nonetheless, using specCNNspec, several coupled spins in addition to the major singlets can be quantified from tFID128 with the error no larger than 10%.

Conclusion

Upon the availability of more realistically simulated training data, CNNs can also be used in the reconstruction of spectra from truncated FIDs.
Surface Modification with Control over Ligand Density for the Study of Multivalent Biological Systems
Authors: Di Iorio Daniele , Huskens Jurriaan
Published: January 2020

In the study of multivalent interactions at interfaces, as occur for example at cell membranes, the density of the ligands or receptors displayed at the interface plays a pivotal role, affecting both the overall binding affinities and the valencies involved in the interactions. In order to control the ligand density at the interface, several approaches have been developed, and they concern the functionalization of a wide range of materials. Here, different methods employed in the modification of surfaces with controlled densities of ligands are being reviewed. Examples of such methods encompass the formation of self‐assembled monolayers (SAMs), supported lipid bilayers (SLBs) and polymeric layers on surfaces. Particular emphasis is given to the methods employed in the study of different types of multivalent biological interactions occurring at the functionalized surfaces and their working principles.
Design, Synthesis and Self‐Assembly of Functional Amphiphilic Metallodendrimers
Authors: Neranon Kitjanit , Alberch Laura , Ramström Olof
Published: January 2020

A new family of alkynylated, amphiphilic dendrimers consisting of amidoamine linkers connected to 5,5′‐functionalized 2,2′‐bipyridine cores has been developed and evaluated in the formation of metallodendrimers of different generations and in self‐assembly protocols. A convergent synthetic strategy was applied to provide dumbbell‐shaped amphiphilic dendrimers, where the 2,2′‐bipyridine cores could be coordinated to FeII centers to afford corresponding metallodendrimers. The ability of the metallic‐ and non‐metallic dendritic structures to self‐assemble into functional supramolecular aggregates were furthermore evaluated in aqueous solution. Spherical aggregates with sizes of a few hundred nanometers were generally produced, where controlled disassembly of the metallodendrimers through decomplexation could be achieved.