bluuebunny/crossref_metadata_2025 huggingface dataset:
Glycerin‐based nitrogen applications for turfgrass growth
Authors: Mertz Isaac , Thoms Adam , Christians Nick
Published: July 2021

The purpose of this study was to investigate the effects of a glycerin‐based nitrogen source on lateral spreading and recovery from simulated injury in both creeping bentgrass (Agrostis stolonifera L.)(CB) and Kentucky bluegrass (Poa pratensis L.)(KBG) . To evaluate the effect on lateral spreading and recovery, applications of the glycerin‐based N product (glycerin + N) were compared with equal urea‐N applications using N application rates of 6.1, 12.2, and 24.4 kg N ha−1. To test the effect of the N treatments on recovery from simulated turf injury, injury was imposed on mature stands of CB and KBG by a golf course cup cutter, and recovery was tracked via digital image analysis over time. In a separate study, effects on lateral stem growth were investigated by transplanting mature plugs of CB and KBG to plots containing no existing vegetation, and digital image analysis was used to track the outward spreading of the CB and KBG plugs over time. Both studies were repeated in time across 2 yr. Compared with urea‐N, the glycerin + N treatments resulted in increased turf injury recovery of CB and KBG by 43.9 and 44.7%, respectively, when applied at 24.4 kg N ha−1. Additionally, the glycerin + N treatments resulted in increased spreading of vegetative plugs by 60.25% and 53.7%, respectively, in CB and KBG when applied at 24.4 kg N ha−1.  The glycerin+N material may be a valuable tool for turf managers for increasing the rate of recovery in CB and KBG following damage.
The impact of HIV/AIDS on human capital investment in Sub‐Saharan Africa: New evidence
Authors: Chicoine Luke , Lyons Emily , Sahue Alexia
Published: July 2021

The risk of AIDS‐related mortality increased dramatically throughout the 1990s. This paper updates previous work by Fortson (2011) to examine the impact of mortality risk on human capital investment during the deadliest period of the pandemic. We combine Demographic Health Survey data from 30 countries, across 60 survey waves, to generate a sample of over 1,300,000 observations. Cohort‐specific analysis using the updated sample yields new evidence that the negative relationship between HIV prevalence and schooling steepened as mortality risk increased. The reduction in schooling is largest for women, and along the extensive margin of the schooling decision. The findings indicate that the decline in human capital investment associated with the HIV/AIDS pandemic prior to the availability of treatment was larger in magnitude than previously understood, but may be reversing rapidly as access to treatment is expanded.
Apheresis practice patterns in the United States of America: Analysis of a market claims database
Authors: Zantek Nicole D. , Martinez Ryan J. , Johnson Andrew D. , Tholkes Anthony J. , Shah Surbhi
Published: July 2021

Introduction

Indications for apheresis procedures are expanding; however, the evidence for many is low quality. A better understanding of apheresis patterns in the United States is needed to better plan prospective research studies.

Methods

Data from January 1, 2013, to September 30, 2015, were analyzed from the IBM MarketScan Research Databases of de‐identified health insurance claims data of several million enrollees at all levels of care from large employers and health plans across the United States. Apheresis procedures were identified by International Classification of Diseases, Ninth version (ICD‐9) and Current Procedure Terminology (CPT) codes.

Results

Combining inpatients and outpatients, 18 706 patients underwent 70 247 procedures. The patients were 52.7% female, 5.1% <18 years, and 55.9% inpatient, while the procedures were 49.5% female, 5.7% <18 years, and 19.8% inpatient. For each apheresis modality, the percent of patients treated and procedures performed, respectively, are plasmapheresis 36.4% and 42.5%, autologous harvest of stem cells 22.8% and 10.7%, plateletpheresis 11.1% and 3.5%, allogeneic harvest of stem cells 8.2% and 2.5%, photopheresis 5.4% and 24.4%, erythrocytapheresis 3.8% and 4.7%, leukopheresis 2.0% and 0.7%, immunoadsorption 1.4% and 0.4%, extracorporeal selective adsorption/filtration and plasma reinfusion 1.0% and 3.6%, and other 21.6% and 6.9%. A wide variety of diagnoses were treated; however, analysis of the diagnoses suggests the procedure codes may not always reflect an apheresis procedure.

Conclusion

This study describes the landscape of apheresis in the United States, but may overestimate some procedures based on linked diagnosis codes. Direct measures of apheresis procedures are needed to plan future research studies.
Ameliorative effect and mechanism of Yi‐Suan‐Cha against hyperuricemia in rats
Authors: Qin Yuanyuan , Zhang Xuan , Tao Hui , Wu Yangyang , Yan Jie , Liao Lin , Meng Jianjun , Lin Faquan
Published: July 2021

Background

This study aimed to evaluate the urate‐lowering effects of Yi‐Suan‐Cha and explore its underlying mechanisms in experimental hyperuricemia induced in rats.

Methods

Forty‐eight male SD rats were randomly allocated into normal control, model, allopurinol, benzbromarone, low‐dose Yi‐Suan‐Cha (0.2 g/ml), and high‐dose Yi‐Suan‐Cha (0.4 g/ml) groups (n = 8 rats per group). Rat models of hyperuricemia were established through intragastric administration of adenine 25 mg/kg + potassium oxalate 300 mg/kg for 3 weeks. After the last administration, serum uric acid, creatinine, and urea nitrogen levels were measured. Renal histopathology was observed by hematoxylin‐eosin staining. Xanthine oxidase level in serum and liver homogenates was measured by ELISA. The protein and mRNA expression of URAT1, ABCG2, OAT1, and GLUT9 in the kidney was detected by Western blotting and RT‐PCR, respectively.

Results

The serum uric acid levels were significantly lowered in all medication groups than in the model group. The benzbromarone and both Yi‐Suan‐Cha groups showed clear kidney structures with no obvious abnormalities. Compared with the normal control group, the model group showed increased URAT1/GLUT9 protein expression and decreased ABCG2/OAT1 protein expression. Compared with the model group, both Yi‐Suan‐Cha groups showed decreased URAT1/GLUT9 protein expression and increased ABCG2/OAT1 protein expression. Compared with that in the normal control group, URAT1/GLUT9 mRNA expression increased in the model group. Compared with the model group, the low‐dose and high‐dose Yi‐Suan‐Cha groups showed decreased URAT1/GLUT9 mRNA expression and increased ABCG2/OAT1 mRNA expression.

Conclusion

Yi‐Suan‐Cha may lower uric acid level by downregulating URAT1/GLUT9 expression and upregulating ABCG2/OAT1 expression.
Evaluating the accuracy and diagnostic value of CFW and a new fluorescent reagents, fluorescent brightener 85, for the diagnosis of vulvovaginal candidiasis
Authors: Zhao Yunzhuan , Yu Zixuan , Yue Xueping
Published: July 2021

Background

Vulvovaginal candidiasis (VVC) is a common vaginitis in females. The commonly used diagnostic method, 10% potassium hydroxide (KOH) smear microscopy, makes it not very easy to recognize fungi.

Methods

Vaginal secretions were collected from clinically suspected VVC patients and divided into four groups and examined using KOH, CFW (Calcofluor White), FB 85(fluorescent brightener 85), and culture. The data were statistically analyzed.

Results

In total, 110 patients with suspected VVC were recruited. The positive rates of KOH, CFW, FB 85, and the culture method were 68.2%, 64.5%, 61.8%, and 77%, respectively. According to the McNemar test, there was no statistically significant difference between the KOH, CFW, and the FB 85 methods (p > 0.05). However, CFW had a shorter diagnosis time than the KOH method and had a statistically significant difference (p < 0.001). Moreover, CFW has the highest sensitivity, specificity, and accuracy. In morphological recognition, it was easier to recognize fungal structures with CFW and FB 85 than with the KOH.

Conclusions

The fluorescent method is a good method for the diagnosis of VVC. And the fungi can be found more quickly. Similar to CFW, FB 85 is also a potential good fluorescent reagent for the diagnosis of VVC and has potential value for application in clinical fungal infection diseases.
Oxidation of cadaverine by putrescine oxidase from Rhodococcus erythropolis
Authors: Anyanwu Valentine E , Hall Stephen J , Stephens Gill , Pordea Anca
Published: July 2021

BACKGROUND

Putrescine oxidase (EC 1.4.3.10) is of interest for the microbial production of unsubstituted platform nitrogen (N‐)heterocycles, because it only requires inexpensive oxygen as co‐substrate. Putrescine oxidase from Rhodococcus erythropolis (Re‐PuO) was shown previously to catalyze the oxidation of cadaverine; however, there is little information in the literature about the robustness of this enzyme for biotechnological applications. The aim of this study was to investigate the suitability of Re‐PuO for the bioproduction of 1‐piperideine from cadaverine under different reaction conditions.

RESULTS

The formation of 1‐piperideine catalyzed by Re‐PuO was demonstrated using o‐aminobenzaldehyde as a reagent to trap the cyclic imine and shift the equilibrium for cyclization. A direct assay of Re‐PuO activity for cadaverine oxidation was then implemented, by monitoring oxygen consumption. Characterization of the reaction mixture by 1H NMR and mass spectrometry confirmed the presence of piperideine dimers and trimers, yet the quantification of the reaction products could not be achieved. The optimum temperature and pH conditions for enzyme activity were determined as 55 °C and 8.5, respectively. At pH 7.5, the enzyme retained its activity after 65 h incubation at 25 °C, but lost 75% of its activity after 1 h incubation at 55 °C. The enzyme showed no substrate inhibition at concentrations as high as 100 mmol L–1 cadaverine. Complete biotransformation of cadaverine was observed in whole cells at physiological conditions.

CONCLUSIONS

These results successfully demonstrate the potential of putrescine oxidase for the bioproduction of N‐heterocycles from cadaverine. © 2021 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).
Assessing grit as a potential additional domain for dental students' selection
Authors: Baharuddin Izyan Hazwani , Khrul Fazri Khamila Hani , Mohamad Safran Hani , Abdul Rahim Mohd Aizat , Ismail Ikmal Hisham
Published: July 2021

Background: Unhappiness, stress, and burnout will often lead to low academic performance among dental students. Perseverance and passion for long‐term goal, known as grit, could overcome these despondent emotions. Our Study is looking at whether grit should be added as another domain during the interview process. The main objective of this study was to determine the association between grit and happiness among Universiti Teknologi MARA (UiTM) dental students. In addition to that, the prevalence of gritty and happy dental students in UiTM was also determined and compared across the years of study.

Methods: This was a cross‐sectional study. Validated Short Grit Scale (Grit‐S) and Pemberton Happiness Index (PHI) were distributed to all 409 undergraduate dental students in Faculty of Dentistry, UiTM through their class representatives. Scores for both grit and happiness were calculated according to their instruction manual. Data were analyzed using SPSS Version 25 by descriptive analysis, one‐way ANOVA, independent t‐test, Pearson's correlation, and linear regression.

Result: Two hundred sixty‐six students returned the answered questionnaires, yielding a response rate of 65%. Prevalence of gritty and happy UiTM dental students was found to be at 79% and 41%, respectively. There was a significant positive fair linear correlation between grit and happiness among dental students (r = 0.225, p < 0.001). A significantly higher happiness score is observed among gritty student (p < 0.001).

Conclusion: While this study demonstrated high prevalence of grit, prevalence of happiness among UiTM dental students was low. Higher grit score had a positive impact on happiness score among dental students in UiTM. For this reason, grit may be considered as an additional element in selecting upcoming dental students.
Splenic infarction in sickle cell trait: A comprehensive systematic review of case studies
Authors: Jefferson Jamal M. , Sims Wynton M. , Umeh Nkeiruka , Byeon Yen Ji Julia , Abdallah Khadijah E. , Bonham Vence L. , Naik Rakhi P. , Smith‐Whitley Kim
Published: July 2021

Sickle cell trait (SCT), a commonly asymptomatic condition, has many associated clinical complications that upon presentation, can be very difficult to attribute to SCT. The effects of SCT on the spleen, for example, are not completely understood, though there have been a number of case reports detailing related complications in diverse populations. Our objective was to perform the first comprehensive case report review of splenic infarction in SCT patients to highlight the relevance of this seemingly rare condition. We conducted an extensive literature search reviewing case reports and case series of acute splenic infarctions from 1970 to 2020. This comprehensive search resulted in 54 articles with a total of 85 individuals. The ages ranged from 7 to 65, 12% were female. Individuals were of African‐American (26%), European (16%), South Asian (13%), Middle Eastern (7%), Latin American (7%), North or East African (4%), Mediterranean (4%), West African (1%), and unknown (22%) origins. Although splenic infarct in SCT patients has been associated with high altitudes, 39% of cases reporting altitude occurred below 3000 m. Among cases where HbS values were recorded, 88% occurred in individuals with HbS levels higher than 35%, suggesting that high HbS values may be a risk factor for splenic infarction. Our findings indicate that splenic infarct occurs across a wide range of demographic populations and environmental settings. While our understanding of SCT evolves, the findings here suggest that future advances in research and healthcare could benefit more from real‐time surveillance and registry initiation for various SCT outcomes such as splenic infarct.
A comparative study on Suzuki‐type 11C‐methylation of aromatic organoboranes performed in two reaction media
Authors: Rokka Johanna , Nordeman Patric , Roslin Sara , Eriksson Jonas
Published: July 2021

The Suzuki‐type cross coupling reaction is a palladium‐mediated multistep reaction that has been used to synthesize several 11C‐labeled tracers for PET. However, the impact of the selected organoborane reagent and reaction medium on the radiochemical yield (RCY) has not been thoroughly investigated. To bridge this gap, we studied the synthesis of 1‐[11C]methylnaphthalene using four different organoborane precursors in reactions performed in DMF/water and THF/water. In the synthesis of 1‐[11C]methylnaphthalene, the best radiochemical yields (RCYs), approximately 50%, were obtained with boronic acid and pinacol ester precursors, whereas less than 4% RCY was obtained when performing the reaction with the N‐methylimidodiacetic acid boronic ester (MIDA ester) precursor. 1‐[11C]methylnaphthalene was obtained in higher yields in almost all syntheses performed in THF/water as compared to DMF/water. This observation was in line with previously reported results for [11C]UCB‐J, a tracer for the synaptic vesicle glycoprotein 2A (SV2A) receptor, that also was obtained in higher RCY when synthesized in THF/water. The same trend was observed with [11C]cetrozole, where the RCY was more than doubled in THF/water compared to the previously published synthesis performed in DMF. These results suggest that THF/water could be the preferred reaction medium when producing PET tracers via the Suzuki‐type coupling reaction.
Structural elucidation of dipeptides displaying limited mass spectral information by liquid chromatography–electrospray ionization–tandem mass spectrometry
Authors: Madmon Moran , Weissberg Avi
Published: July 2021

Small peptides, such as dipeptides, have attracted attention in many research fields because of their important biological functions and potential roles as disease biomarkers. However, the identification of many of them by implementation of liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS) is a challenging task. This is because many dipeptides display limited mass spectral information in LC–ESI–MS/MS analyses, which leads to unavoidable ambiguity in determinations of their structures. In this study, two useful analytical techniques were developed for the structural elucidation of 10 representative dipeptides exhibiting a dominant/single product ion in the ESI–MS/MS spectra of the protonated molecules [M + H]+. Structural elucidation was obtained instantaneously through LC–ESI–MS/MS fragmentation of the accompanying sodium adducts [M + Na]+ or alternatively by “in‐vial” chemical derivatization with isobutyl chloroformate. The sodium adducts and the resulting carbamate derivatives altered the charge distribution occurring during ESI–MS/MS fragmentation, enabling detailed structural elucidation and unambiguous identification of such dipeptides at ng/ml levels. These quick, simple, and easy techniques can be implemented to identify various dipeptides or confirm their identities without the need for complex sample handling.
Frequency domain behavior of S‐parameters piecewise‐linear fitting in a digital‐wave framework
Authors: Belforte Piero , Spina Domenico , Astorino Maria Denise , Antonini Giulio , Ferrari Maurizio
Published: July 2021

This paper describes PWLFIT+, an extension to the frequency domain of PWLFIT, a new paradigm in time‐domain macromodeling for linear multiport systems, based on a piecewise‐linear (PWL) behavioral representation of the S‐parameters step response. While the impulse response of each S‐parameter is approximated as sum of delayed rectangles (rect) functions, its spectrum is interpolated as sum of the corresponding delayed cardinal sine (sinc) functions. Exploiting this correspondence, the model building is performed by an iterative procedure where the PWL macromodels can be determined in order to meet defined accuracy goals on the spectrum. At runtime, waves at macromodels ports are calculated using the Segment Fast Convolution (SFC) algorithm within the Digital Wave Simulator (DWS) framework. The proposed method is characterized by its simplicity, stability, speed and scalability, all features that are emphasized when it is used in the DWS framework. After an analysis of the excellent numerical features of SFC in the Z‐domain, clearly differentiated with respect conventional macromodeling methods based on poles and residues, two suitable application examples are presented to demonstrate the unique features of PWLFIT+.
Changes in temperature and heat waves over Africa using observational and reanalysis data sets
Authors: Engdaw Mastawesha Misganaw , Ballinger Andrew P. , Hegerl Gabriele C. , Steiner Andrea K.
Published: July 2021

Providing comprehensive regional‐ and local‐scale information on changes observed in the climate system plays a vital role in planning effective and efficient climate change adaptation options, specifically over resource‐limited regions. Here, we assess changes in temperature and heat waves over different regions of the African continent, with a focus on spatiotemporal trends and the time of emergence of change in hot extremes from natural variability. We analyse absolute and relative threshold indices. Data sets include temperatures from observations (CRUTS4.03 and BEST) and from three representative state‐of‐the‐art reanalyses (ERA5, MERRA2 and JRA‐55) for the common period 1980–2018. Statistically significant warming is observed over all regions of Africa in temperature time series from CRU observations and reanalysis data, although the trend strength varies between data sets. Also, extreme temperatures and heat wave indices from BEST observations and all reanalysis data sets reveal increasing trends over all regions of the African continent. However, there are differences in both trend strength and time evolution of heat wave indices between different reanalysis data sets. Most data sets agree in identifying 2010 as a peak heat year over Northern and Western Africa while Eastern and Southern Africa experienced the highest heat wave occurrence in 2016. Our results clearly reveal that heat wave occurrences have emerged from natural climate variability in Africa. The earliest time of emergence takes place in the Northern Africa region in the early 2000s while in the other African regions emergence over natural variability is found mainly after 2010. This also depends on the respective index metrics, where indices based on more consecutive days show later emergence of heat wave trends. Overall, significant warming and an increase in heat wave occurrence is found in all regions of Africa and has emerged from natural variability in the past one or two decades.
Effect of heat treatment on the chromium‐depleted zones of a high carbon martensitic stainless steel
Authors: Siqueira Jordânio S. , de Abreu Alves Marcos R. , Marcial Luiz Thaís , Renzetti Reny A.
Published: July 2021

Heat treatments are commonly applied in the martensitic stainless steels to achieve high wear resistance and hardness; however, they can lead to a decrease in corrosion resistance due to the precipitation of chromium‐rich carbides. The present work investigates the effect of austenitizing and tempering parameters on the microstructure, hardness, and passivation and reactivation currents of AISI 440C. A double‐loop electrochemical potentiodynamic reactivation test is performed to evaluate the dissolution and precipitation of chromium‐rich carbides. The volume fraction of phases after heat treatment is estimated by X‐ray diffraction. Results show that an increase in the austenitizing temperature leads to an increase in the carbide dissolution, and also in the amount of retained austenite. As a consequence, low passivation and reactivation currents are obtained. When austenite is the main phase, the increase of austenitizing time contributed to an increase in the degree of sensitization due to austenite grain boundary carbon enrichment. However, the presence of austenite after tempering kept part of the carbon in a solid solution resulting in low passivation and reactivation currents.
High‐temperature high‐pressure SCC testing of corrosion‐resistant alloys
Authors: Galakhova Anastasiia , Prattes Karl , Mori Gregor
Published: July 2021

Stress corrosion cracking test methods of corrosion‐resistant alloys are reviewed. The interest to write a review on this topic was drawn by demands for oil country tubular goods applicable in deep wells with high pressures, high temperatures, and the presence of H2S, where stress corrosion cracking is one of the most critical failure modes. All conventional methods for determining the stress corrosion cracking resistance of an alloy, mainly slow strain rate testing, constant load testing (tensile, 4‐PB), constant strain testing (U‐bend, C‐ring), and fracture mechanics (double cantilever beam sample) are covered. Considering the variety of testing solutions, the field of search is narrowed to hot (up to 250°C) aqueous chloride solutions with dissolved H2S and CO2gases under high pressure (up to 200 bar total pressure).
Boundedness results for 2‐adic Galois images associated to hyperelliptic Jacobians
Authors: Yelton Jeffrey
Published: July 2021

LetKbe a number field, and letCbe a hyperelliptic curve overKwith JacobianJ. Suppose thatCis defined by an equation of the form for some irreducible monic polynomial of discriminant Δ and some element . Our first main result says that if there is a prime ofKdividing but not (2Δ), then the image of the natural 2‐adic Galois representation is open in and contains a certain congruence subgroup of depending on the maximal power of dividing . We also present and prove a variant of this result that applies whenCis defined by an equation of the form for distinct elements . We then show that the hypothesis in the former statement holds for almost all and prove a quantitative form of a uniform boundedness result of Cadoret and Tamagawa.
STAT3 polymorphisms in North Africa and its implication in breast cancer
Authors: Ziadi Wafa , Boussetta Sami , Elkamel Sarra , Pakstis Andrew J. , Kidd Kenneth K. , Medimegh Imen , Ben Ammar Elgaaied Amel , Cherni Lotfi
Published: July 2021

Background

Only a few studies have investigated the association of single nucleotide polymorphisms in STAT3 gene with the susceptibility to cancer and response to chemotherapy. Our aim was to determine the allele frequencies of rs3869550, rs957971, and rs7211777 at the STAT3 gene in North African populations and compare them to 1000 genomes populations, and to investigate their relation with cancer.

Methods

The targeted SNPs have been analyzed in six Tunisian populations and a sample of Libyans using TaqMan® Assay. The results were compared to 1000 Genomes Project population samples. Targeting of the regions encompassing the three SNPs by micro‐ARN was assessed using miR databases.

Results

The analysis of the 3 SNPs showed that North African populations were close to South Asians. As expected, African populations presented a significant frequency of the ancestral CCG haplotype in contrast to other populations where the fully derived TGA haplotype was more frequent. The presence and diversity of rare haplotypes at STAT3 in North African populations could have been generated by recombination between the two major haplotypes. A screening of the micro‐RNA databases showed that the STAT3 region with the mutated allele of rs7211777 (G>A) could be targeted by miR hsa‐miR‐3606‐5p, which also targets genes involved in breast cancer.
Technical Note: A preliminary study of dual‐tracer PET image reconstruction guided by FDG and/or MR kernels
Authors: Wang Haiyan , Huang Zhenxing , Zhang Qiyang , Gao Dongfang , OuYang Zhanglei , Liang Dong , Liu Xin , Yang Yongfeng , Zheng Hairong , Hu Zhanli
Published: July 2021

Purpose

Clinically, single radiotracer positron emission tomography (PET) imaging is a commonly used examination method; however, since each radioactive tracer reflects the information of only one kind of cell, it easily causes false negatives or false positives in disease diagnosis. Therefore, reasonably combining two or more radiotracers is recommended to improve the accuracy of diagnosis and the sensitivity and specificity of the disease when conditions permit.

Methods

This paper proposes incorporating 18F‐fluorodeoxyglucose (FDG) as a higher‐quality PET image to guide the reconstruction of other lower‐count 11C‐methionine (MET) PET datasets to compensate for the lower image quality by a popular kernel algorithm. Specifically, the FDG prior is needed to extract kernel features, and these features were used to build a kernel matrix using a k‐nearest‐neighbor (kNN) search for MET image reconstruction. We created a 2‐D brain phantom to validate the proposed method by simulating sinogram data containing Poisson random noise and quantitatively compared the performance of the proposed FDG‐guided kernelized expectation maximization (KEM) method with the performance of Gaussian and non‐local means (NLM) smoothed maximum likelihood expectation maximization (MLEM), MR‐guided KEM, and multi‐guided‐S KEM algorithms. Mismatch experiments between FDG/MR and MET data were also carried out to investigate the outcomes of possible clinical situations.

Results

In the simulation study, the proposed method outperformed the other algorithms by at least 3.11% in the signal‐to‐noise ratio (SNR) and 0.68% in the contrast recovery coefficient (CRC), and it reduced the mean absolute error (MAE) by 8.07%. Regarding the tumor in the reconstructed image, the proposed method contained more pathological information. Furthermore, the proposed method was still superior to the MR‐guided KEM method in the mismatch experiments.

Conclusions

The proposed FDG‐guided KEM algorithm can effectively utilize and compensate for the tissue metabolism information obtained from dual‐tracer PET to maximize the advantages of PET imaging.
A hybrid Laplace‐Galerkin method for thermo‐hydro‐mechanical coupling in fluid saturated porous media: Application for borehole problems
Authors: Nguyen‐Sy Tuan , Vu Minh‐Ngoc , Nguyen Thoi‐Trung
Published: July 2021

A hybrid Laplace‐Galerkin method is proposed for modeling thermo‐hydro‐mechanical coupled problems of fluid saturated porous media in unsteady state regime. It consists of transforming the weak form equations into the Laplace space where they are solved by the Galerkin finite element method. Results in time space are then obtained by the Stehfest method of inverse Laplace transformation. This technique does not require any time stepping comparing to the traditional implicit or explicit time discretization method. Its exactitude is confirmed by comparing with existent analytical results as well as the one obtained by the implicit time stepping method.
Hands‐on horticulture: Lessons learned teaching online experiential horticulture during COVID‐19
Authors: Luby Claire , Tepe Emily , Irish Laura , Michaels Thomas , Hoover Emily
Published: July 2021

As a result of theCOVID‐19 pandemic, many courses were forced online. This posed particular challenges for courses with laboratory or hands‐on components. A group of instructors at the University of Minnesota and the University of Wisconsin‐Madison designed an online, asynchronous course structure for teaching introductory horticulture courses with laboratory components. Uniquely, the courses described in this article, while delivered through the online teaching platform Canvas, focused on developing hands‐on activities that got students away from their computers to observe, work with, and grow plants. The course included hands‐on activities that complemented lecture readings and videos and guided students through designing and setting up experiments in their homes. We heard many positive reviews from student course evaluations for this style of course and want to share the structure and the types of experiential activities we included to engage students with plants and the process of science, as well as lessons that we learned while teaching in this online learning environment. We found that the ability to care for and observe plants on a daily basis wove together the lecture and lab materials in ways that were not previously seen during in‐person courses. As instructors, we would adapt some of the components of these online courses into our in‐person courses in the future.
Could Nintendo’s Animal Crossing be a tool for conservation messaging?
Authors: Fisher Jessica C. , Yoh Natalie , Kubo Takahiro , Rundle Danielle
Published: July 2021

The current extinction crisis demands worldwide commitment to conservation across all sectors of society. By transcending the traditional disciplinary boundaries, conservationists can reach new audiences to communicate pro‐conservation knowledge, education and awareness messages.

There are approximately 2.7 billion video‐gamers worldwide, with millions more joining as a result of global lockdowns. In March 2020, Animal Crossing: New Horizons was released by Nintendo, fast becoming the second‐best selling video game ever in Japan, and selling over 26.4 million units worldwide. Unlike many popular video games, its unique premise involves players creating an island, growing vegetation, catching wildlife and donating fossils and species to a museum. The game has been praised for its positivity, escapism and measurable benefits to mental well‐being.

Here, we articulate how different features of the game, including the islands, their biodiversity and inhabitants, encourage players to exhibit pro‐conservation behaviours and attitudes (e.g. recycling litter, or planting a diversity of flowers), as well as improving players’ knowledge about the diversity of relatively little known taxa (marine and freshwater fishes and invertebrates). We also highlight where pitfalls exist (e.g. encouraging the collection of threatened species). We principally frame these discussions in the context of Japan's cultural relationship with the natural world, including its history of insect‐collecting and its management of green spaces. We conclude by outlining some recommendations about potential improvements to future releases, or for similar games, that could further promote conservation messaging.

This perspective sheds light on the avenues through which Animal Crossing: New Horizons encourages pro‐conservation knowledge, attitudes and behaviours of its international audience, with potential for these experiences to translate into real‐world conservation actions. During a critical time in humanity's history, video gaming could therefore provide a huge opportunity for communicating conservation messages to billions of people worldwide.

A free Plain Language Summary can be found within the Supporting Information of this article.
Leukaemia and lockdown: The delayed infection model of childhood acute lymphoblastic leukaemia and the COVID‐19 pandemic
Authors: Lillie Katy
Published: July 2021

Acute lymphoblastic leukaemia (ALL) is the most common type of leukaemia diagnosed in children. The prevailing hypothesis regarding pathogenesis of childhood ALL was developed by Greaves, and states that ALL is caused by an abnormal immune response to a common infection. The response arises either due to naivety of the immune system caused by a lack of common childhood infections, or genetic susceptibility due to specific alleles. The former explanation is known as the delayed infection hypothesis. COVID‐19 is a new infection that no children in the UK were exposed to prior to 2020. Furthermore, the lockdown measures designed to prevent spread of this virus have also greatly reduced spread of other common infections. It is therefore important to examine the evidence for this hypothesis, and to consider it in the context of the pandemic to determine what effect lockdown measures may have on incidence of ALL in children.
Bias of time‐varying exposure effects due to time‐varying covariate measurement strategies
Authors: Penning de Vries Bas B. L. , Groenwold Rolf H. H.
Published: July 2021

Purpose

In studies of effects of time‐varying drug exposures, adequate adjustment for time‐varying covariates is often necessary to properly control for confounding. However, the granularity of the available covariate data may not be sufficiently fine, for example when covariates are measured for participants only when their exposure levels change.

Methods

To illustrate the impact of choices regarding the frequency of measuring time‐varying covariates, we simulated data for a large target trial and for large observational studies, varying in covariate measurement design. Covariates were measured never, on a fixed‐interval basis, or each time the exposure level switched. For the analysis, it was assumed that covariates remain constant in periods of no measurement. Cumulative survival probabilities for continuous exposure and non‐exposure were estimated using inverse probability weighting to adjust for time‐varying confounding, with special emphasis on the difference between 5‐year event risks.

Results

With monthly covariate measurements, estimates based on observational data coincided with trial‐based estimates, with 5‐year risk differences being zero. Without measurement of baseline or post‐baseline covariates, this risk difference was estimated to be 49% based on the available observational data. With measurements on a fixed‐interval basis only, 5‐year risk differences deviated from the null, to 29% for 6‐monthly measurements, and with magnitude increasing up to 35% as the interval length increased. Risk difference estimates diverged from the null to as low as −18% when covariates were measured depending on exposure level switching.

Conclusion

Our simulations highlight the need for careful consideration of time‐varying covariates in designing studies on time‐varying exposures. We caution against implementing designs with long intervals between measurements. The maximum length required will depend on the rates at which treatments and covariates change, with higher rates requiring shorter measurement intervals.
Retracted: Prevalence and factors associated with bone stress injury in middle school runners
Authors: Tenforde Adam S. , DeLuca Stephanie , Wu Alexander C. , Ackerman Kathryn E. , Lewis Margo , Rauh Mitchell J. , Heiderscheit Bryan , Krabak Brian J. , Kraus Emily , Roberts William , Troy Karen L. , Barrack Michelle T.
Published: July 2021

Background

Bone stress injury (BSI) in youth runners is clinically important during times of skeletal growth and is not well studied.

Objective

To evaluate the prevalence, anatomical distribution, and factors associated with running‐related BSI in boy and girl middle school runners.

Design

Retrospective cross‐sectional study.

Setting

Online survey distributed to middle school runners.

Methods

Survey evaluated BSI history, age, grade, height, weight, eating behaviors, menstrual function, exercise training, and other health characteristics.

Main Outcome Measurements

Prevalence and characteristics associated with history of BSI, stratified by cortical‐rich (eg, tibia) and trabecular‐rich (pelvis and femoral neck) locations.

Participants

2107 runners (n = 1250 boys, n = 857 girls), age 13.2 ± 0.9 years.

Results

One hundred five (4.7%) runners reported a history of 132 BSIs, with higher prevalence in girls than boys (6.7% vs 3.8%, p = .004). The most common location was the tibia (n = 51). Most trabecular‐rich BSIs (n = 16, 94% total) were sustained by girls (pelvis: n = 6; femoral neck: n = 6; sacrum: n = 4). In girls, consuming <3 daily meals (odds ratio [OR] = 18.5, 95% confidence interval [CI] = 7.3, 47.4), eating disorder (9.8, 95% CI = 2.0, 47.0), family history of osteoporosis (OR = 6.9, 95% CI = 2.6, 18.0), and age (OR = 1.6, 95% CI = 1.0, 2.6) were associated with BSI. In boys, family history of osteoporosis (OR = 3.2, 95% CI = 1.2, 8.4), prior non‐BSI fracture (OR = 3.2, 95% CI = 1.6, 6.7), and running mileage (OR = 1.1, 95% CI = 1.0, 1.1) were associated with BSI. Participating in soccer or basketball ≥2 years was associated with lower odds of BSI for both sexes.

Conclusion

Whereas family history of osteoporosis and prior fracture (non‐BSI) were most strongly related to BSI in the youth runners, behaviors contributing to an energy deficit, such as eating disorder and consuming <3 meals daily, also emerged as independent factors associated with BSI. Although cross‐sectional design limits determining causality, our findings suggest promoting optimal skeletal health through nutrition and participation in other sports including soccer and basketball may address factors associated with BSI in this population.
Development of evidence‐based classification for para surfers with physical impairments: A narrative review
Authors: Johnson Maureen E. , David Heather M.
Published: July 2021

The sport of competitive para surfing is growing internationally without established classification procedures. A classification structure is essential for equitable sport competition and worldwide sport progression. This narrative review summarizes the existing knowledge on Paralympic classification and surfing biomechanics. Its primary purpose is to describe the development of an evidence‐based para surfing classification structure that follows the International Paralympic Committee (IPC) Classification Code. Two databases—PubMed and Google Scholar—were searched for three themes: “Paralympic classification”, “performance determining factors in surfing”, and “impact of impairments on surf performance”. The IPC Classification Code and IPC regulations were obtained from the IPC website and official publications. Seventy‐six relevant articles were utilized to guide the design of this preliminary para surfing classification structure. A conceptual framework on athlete characteristics, adaptive sport characteristics, and use of equipment is presented to build the essential knowledge base for continual growth of para surfing. This classification structure and conceptual framework will support para surfing sport expansion and help pave the way for its inclusion in the Paralympic Games.
Transport and co‐transport of carboxylate ions and alcohols in cation exchange membranes
Authors: Kim Jung Min , Beckingham Bryan S.
Published: July 2021

Understanding multi‐component transport behavior through hydrated dense membranes is of interest for numerous applications. For the particular case of photoelectrochemical CO2 reduction cells (PEC‐CRC), it is important to understand the multi‐component transport behavior of CO2 electrochemical reduction products including mobile carboxylates (formate and acetate) and alcohols (methanol and ethanol) in the ion exchange membranes as one role of the membrane in these devices is to minimize the permeation of these CO2 reduction products to the anolyte as they often oxidize back to CO2. Cation exchange membranes (CEM) are promising candidates for such devices as they act to minimize the permeation of mobile anions, such as carboxylates. However, the design of new CEMs is necessary as the permeation of carboxylates often increases in co‐permeation with alcohols. Here, we investigate the transport behavior of carboxylates and alcohols in two types of CEMs (1) a crosslinked CEM was prepared by free‐radical copolymerization of a sulfonated monomer (AMPS) with a crosslinker (PEGDA), and (2) Nafion® 117. We observe an increase in both PEGDA‐AMPS and Nafion® 117 diffusivities to carboxylates in co‐diffusion with alcohols. We attribute this behavior to charge screening by co‐diffusing alcohol that reduces the electrostatic repulsion between bound sulfonates and mobile carboxylates.
The inhibitory effects of different types of Brassica seed meals on the virulence of Ralstonia solanacearum
Authors: Peng Junwei , Liu Hong , Shen Minchong , Chen Ruihuan , Li Jiangang , Dong Yuanhua
Published: July 2021

BACKGROUND

Understanding the specific inhibitory effects of different Brassica seed meals (BSMs) on soilborne pathogens is important for their application as biocontrol agents for controlling plant disease. In this study, the seed meals of Brassica napus L. (BnSM), Brassica campestris L. (BcSM), and Brassica juncea L. (BjSM), and the combined seed meal of BcSM and BjSM (CSM, 1:1), were selected for investigation. The inhibitory effects of these seed meals on the plant pathogen Ralstonia solanacearum (Smith) and tomato bacterial wilt, were assessed and compared.

RESULTS

All the BSMs significantly inhibited the growth of R. solanacearum in vitro. Furthermore, the BSMs could effectively suppress R. solanacearum virulence traits, including motility, exopolysaccharide production, dehydrogenase activity, virulence‐related gene expression, and colonization in the soil. Among them, BjSM showed the best inhibiting effects, and CSM displayed synergic toxicity against R. solanacearum. In addition, the predominant antibacterial compounds in BcSM and BjSM were identified as the volatile compounds, 3‐butenyl isothiocyanate and allyl isothiocyanate, respectively. Finally, pot experiment verified that the control effects of BjSM and CSM on tomato wilt reached more than 90%.

CONCLUSION

This is the first study to report on the ability of different kinds of BSMs to suppress the virulence of R. solanacearum and biocontrol efficiencies against bacterial wilt in tomato plants. Furtherly, the main antibacterial compounds in the BSMs were identified. The results demonstrated that CSM may possess potential for controlling bacterial wilt caused by R. solanacearum. The results provide a fresh perspective for comprehending the mechanism underlying BSM suppression of pathogens and plant disease.
Lagged ensembles in sub‐seasonal predictions
Authors: Vitart Frédéric , Takaya Yuhei
Published: July 2021

The benefits of using lagged ensembles for S2S predictions have been evaluated using the ECMWF sub‐seasonal to seasonal (S2S) forecasts. The ECMWF S2S forecasts are currently produced twice a week from a 51‐member ensemble. An experiment where the ECMWF forecasts are produced daily instead of twice weekly has been performed to identify the minimum lagged‐ensemble configuration which will produce probabilistic forecasts at least as skilful as the current configuration. Results suggest that the extended‐range prediction of the Madden–Julian Oscillation (MJO) is not deteriorated with the daily lagged ensemble approach, but there is a slight degradation during the first 10 days. In the northern Extratropics, the probabilistic skill scores are improved after week 2 when using lagged ensembles, but only if the daily ensemble size exceeds 20 members. The lagged ensemble approach is more beneficial in the Tropics than in the northern Extratropics, showing even benefits in forecast week 1 over the Tropics, despite the 24 hr difference between two consecutive forecasts. As expected, the daily lagged ensemble method is more beneficial for longer lead times and the optimal lagged ensemble window increases from 2 days for week 2 to 4 days for week 4. An idealized numerical simulation, based on a Monte Carlo approach, confirms the benefits of lagged ensembles. The results obtained are generally consistent with the ECMWF forecast experiment, suggesting that such a simulation could be used as a cheap alternative to address the benefit of lagged versus burst ensembles.
Effect of docosahexaenoic acid on in vitro growth of bovine oocytes
Authors: Nagata Shuta , Tatematsu Kaoru , Yamaguchi Hitoki , Inoue Yuki , Tanaka Keisuke , Tasaki Hidetaka , Shirasuna Koumei , Iwata Hisataka
Published: July 2021

Purpose

The present study investigated the effects of docosahexaenoic acid (DHA) on the growth of bovine oocytes.

Methods

Oocytes and granulosa cell complexes (OGCs) were collected from early antral follicles (0.4‐0.7 mm) on the surface of ovaries harvested from a slaughterhouse. The OGCs were cultured with 0, 1, and 10 μmol/L docosahexanoic acid (DHA) for 16 days.

Results

Antrum formation of the OGCs and the number of granulosa cells (GCs) surrounding the oocytes were comparable among groups, whereas supplementation of 0.1 μmol/L of DHA significantly improved oocyte growth. Oocytes grown with DHA had a higher fertilization rate, acetylation levels of H4K12, and ATP contents, as well as a lower lipid content compared with those grown without DHA. In addition, GCs surrounding OGCs grown with DHA had low lipid content compared with vehicle counterparts. Furthermore, when GCs were cultured in vitro, DHA increased ATP production, mitochondrial membrane potential, and reduced lipid content and levels of reactive oxygen species. RNA‐seq of GCs revealed that DHA increased CPT1A expression levels and affect genes associated with focal adhesion, oxidative phosphorylation, and PI3K‐AKT etc

Conclusion

The results suggest that DHA supplementation affects granulosa cell characteristics and supports oocyte growth in vitro.
Random cographs: Brownian graphon limit and asymptotic degree distribution
Authors: Bassino Frédérique , Bouvel Mathilde , Féray Valentin , Gerin Lucas , Maazoun Mickaël , Pierrot Adeline
Published: July 2021

We consider uniform random cographs (either labeled or unlabeled) of large size. Our first main result is the convergence toward a Brownian limiting object in the space of graphons. We then show that the degree of a uniform random vertex in a uniform cograph is of order n, and converges after normalization to the Lebesgue measure on . We finally analyze the vertex connectivity (i.e., the minimal number of vertices whose removal disconnects the graph) of random connected cographs, and show that this statistics converges in distribution without renormalization. Unlike for the graphon limit and for the degree of a random vertex, the limiting distribution of the vertex connectivity is different in the labeled and unlabeled settings. Our proofs rely on the classical encoding of cographs via cotrees. We then use mainly combinatorial arguments, including the symbolic method and singularity analysis.