bluuebunny/crossref_metadata_2025 huggingface dataset:
Cultural awareness training for dental students
Authors: Alraqiq Hosam M. , Sahota Sukhneet K. , Franks Cheryl L.
Published: June 2021

Objectives

This study aimed to assess the impact of a full‐day workshop on increasing cultural awareness among incoming first‐year (DDS‐I) and post‐doctoral (PGY‐I) dental students at the Columbia University College of Dental Medicine.

Methods

The workshop focused on developing students’ cultural awareness regarding dimensions of identity, recognition of power and privilege, importance of cross‐cultural understanding and communication, and the role of self‐reflection through direct teaching, interactive discussions, and reflective writing. A convenience sample of 83 DDS‐I and 30 PGY‐I students from the 2019 enrollment class were recruited. Assessments included pre‐ and post‐workshop surveys, facilitator interviews, and a formal workshop evaluation. Descriptive and bivariate analyses of students’ responses were performed to assess cultural awareness within and between student groups. Facilitator interviews and student feedback were analyzed qualitatively to identify emerging themes.

Results

Global cultural awareness among both student groups was higher in the post‐workshop survey (for DDS‐I, mean = 3.46, SD = 0.38; for PGY‐I, mean = 3.47, SD = 0.30) than in the pre‐workshop survey (for DDS‐I, mean = 2.98, SD = 0.34; for PGY‐I, mean = 2.90, SD = 0.47), which represented a statistically significant difference (p < 0.001 for both comparisons). Quantitative analysis revealed that the workshop provided a platform to discuss sensitive topics, increased cultural awareness among students and faculty, and provided faculty with different perspectives about culture awareness.

Conclusions

The full‐day workshop achieved its goals of increasing dental students’ self‐perceived cultural awareness and capacity to establish cross‐cultural professional relationships.
Sex and age influence on postural sway during sit‐to‐stand movement in children and adolescents: Cross‐sectional study
Authors: Pavão Silvia Leticia , dos Santos Adriana Neves , Cicuto Ferreira Rocha Nelci Adriana
Published: June 2021

We investigated the influence of sex and age in postural sway during sit‐to‐stand (STS) in children and adolescents of 5–15 years. We evaluated sway during STS in 86 typical participants. STS was divided into three phases: preparation, rising, and stabilization. We calculated for each phase: area, anterior–posterior, and medial–lateral velocity of center‐of‐pressure sway. We applied a stepwise multiple linear regression model to determine if age and sex might be predictors of postural sway during STS. Only age was associated with sway, accounting for between 6.5% and 14.6% of the variability in sway during STS. The age of the subject influences postural sway during STS, but in a small amount. This variable should be taken into account as a variable of control in the assessment of dynamic postural control. Moreover, postural stability during STS was not associated with the sex of the participants.
Remoteness of residence predicts tumor stage, receipt of treatment, and mortality in patients with hepatocellular carcinoma
Authors: Taye Belaynew W , Clark Paul J , Hartel Gunter , Powell Elizabeth E , Valery Patricia C
Published: June 2021

Background and Aim

Surveillance and early detection and curative treatment of hepatocellular carcinoma (HCC) are the mainstay of improving survival for patients, but there are several barriers to achieving this goal. We reported the impact of remoteness of residence on receipt of treatment, tumor stage, and survival in patients with HCC in Queensland.

Methods

We conducted a retrospective cohort study of 1651 HCC patients (147 migrants) from 1 January 2007 to 31 December 2016. We used Wilcoxon rank‐sum test to compare the median age at the time of diagnosis and Bayesian Weibull accelerated failure time regression to identify independent predictors of time to death.

Results

The median survival time after HCC diagnosis was 9.0 months (interquartile range 2.0–24.0). Metropolitan residence (P = 0.02), non‐English language (P < 0.001), foreign country of origin (P < 0.001), and HBV etiology (P < 0.001) were significantly associated with receiving surgical resection for HCC treatment. The strongest predictors of time to death were undifferentiated tumor at presentation (time ratio [TR] = 0.30, 95% credible interval (CrI) 0.23–0.39), age ≥70 years (TR = 0.42, 95% CrI 0.34–0.53), living in remote areas (TR = 0.67, 95% CrI 0.55–0.80), and presence of ≥1 comorbidity (TR = 0.69 95% CrI 0.54–0.90). All the other covariates adjusted, including country of birth (TR = 0.76, 95% CrI 0.49–1.06), did not predict survival time.

Conclusions

Patients living in rural and remote areas had late stage clinical presentation and poor survival. Remoteness of residence may limit access to HCC surveillance in at‐risk patients such as those with cirrhosis, and timely curative treatment to improve survival in these patients.
Concise total synthesis of antiarrhythmic drug dronedarone via a conjugate addition followed intramolecular heck cyclization
Authors: Madhasu Madhu , Doda Sai Reddy , Begari Prem Kumar , Dasari Krishna Rao , Thalari Gangadhar , Kadari Sudhakar , Yadav Jhillu Singh
Published: June 2021

A concise, scalable, and an efficient total synthesis for dronedarone (2) was described using conjugate addition followed by intramolecular Heck cyclization. The other key reaction includes selective reduction of nitro functionality and addition of lithiated terminal alkyne to the aldehyde. The overall yield of this approach is 44% in six steps.
A comprehensive study on the Bayesian modelling of extreme rainfall: A case study from Pakistan
Authors: Ahmad Touqeer , Ahmad Ishfaq , Arshad Irshad Ahmad , Bianco Nicolas
Published: June 2021

In this paper, the modelling of extreme rainfall is carried out in Pakistan by analysing annual daily maximum rainfall data via frequentist and Bayesian approaches. In frequentist settings, the parameters and return levels of the best fitted probabilistic model (i.e., generalized extreme value) are estimated using maximum likelihood and linear moments method. On the other side, under the Bayesian framework, the parameters and return levels are calculated both for noninformative and informative priors. This task is completed with the help of the Markov Chain Monte Carlo method using the Metropolis‐Hasting algorithm. This study also highlights a procedure to build an informative prior through historical records of the underlying processes from other nearby weather stations. The findings attained from the Bayesian paradigm demonstrate that the posterior inference could be affected by the choice of past knowledge used for the construction of informative priors. Additionally, the best method for the modelling of extreme rainfall over the country is decided with the support of assessment measures. In general, the Bayesian paradigm linked with the informative priors offers an adequate estimations scheme in terms of accuracy as compared to frequentist methods, accounting for ambiguity in parameters and return levels. Hence, these findings are very helpful in adopting accurate flood protection measures and designing infrastructures over the country.
Indices for daily temperature and precipitation in Madagascar, based on quality‐controlled and homogenized data, 1950–2018
Authors: Randriamarolaza Luc Yannick Andréas , Aguilar Enric , Skrynyk Oleg , Vicente‐Serrano Sergio M. , Domínguez‐Castro Fernando
Published: June 2021

This study updates knowledge on climate evolution in Madagascar from 1950 to 2018. Changes were analyzed using annual and seasonal climate indices at regional and station level. The original daily series of minimum and maximum temperature and precipitation obtained from 28 meteorological stations were quality controlled and homogenized. Thirty‐seven (37) climate indices were obtained from the daily series. The results show that changes in temperature had a higher degree of spatial coherence than changes in precipitation. Trends for temperature indices were mostly significant at 0.05 level and compatible with warming. Changes in minimum temperatures were greater than those for the maximum, leading to a significant decrease in the diurnal temperature range (DTR). Warm nights increased more than warm days, (0.70 days⋅decade–1) and cold nights decreased more than cold days, (0.21 days⋅decade–1). In addition, we found more stations with significant trends for very cold nights (92.60%) than for very warm days (51.80%) but they progressed differently (decrease and increase, respectively). Station‐by‐station precipitation index trends were mostly non‐significant at 0.05 level, and most regional precipitation index showed decreasing trends. A shift in precipitation magnitude was observed around 2000–2018, a period of intensified drying (where 70.40% of stations recorded non‐significant decreasing trends). An analysis of drought characteristics (i.e., intensity, magnitude and duration) highlighted the situation, especially in the south‐east at an annual timescale.
Biological soil crusts enhance moisture and nutrients in the upper rooting zone of sandy soil agroecosystems
Authors: Nevins Clayton J. , Strauss Sarah L. , Inglett Patrick W.
Published: June 2021

Background: Biological soil crusts (biocrusts) are commonly found in arid ecosystems and are known to have increased carbon (C) and nitrogen (N) concentrations compared to non‐crusted soil. Similar biocrusts were recently identified in Florida, USA sandy soil agroecosystems where they could impact soil biogeochemical cycling, particularly of C and N, in the crop rooting zone.

Aims: Therefore, this research assessed the impacts of biocrusts on soil moisture, available and microbial C and N concentrations, and soil stable N isotopic ratios (δ15N) in the upper rooting zone (0–15 cm) below biocrusts compared to nearby control bare soils without biocrusts.

Methods: Intact soil cores (0–15 cm) were collected from crusted and non‐crusted (control) locations in three sandy soil, citrus agroecosystems. Soil cores were partitioned into three depths: a surface (0–1 cm), a middle (1–5 cm), and a subsurface depth (5–15 cm), and were analyzed for soil moisture and multiple C and N cycling pools.

Results: Biocrust presence and sampling depth (0–1 cm, 1–5 cm, and 5–15 cm) had significant impacts on soil physical, chemical, and biological parameters at the sites. All sites had increased bulk total C and total N, soluble (ammonium, nitrate, dissolved organic N, and salt extractable C), and microbial (microbial biomass C/N) C and N concentrations in the biocrust surface depth compared to the control without biocrusts. Nitrate and total inorganic N (ammonium + nitrate) were enriched below biocrusts (1–5 cm) with one site having 96% and 71% more nitrate and total inorganic N, respectively, under biocrusts compared to controls. This additional plant‐available N was likely provided by the biocrust, as indicated by the δ15N. Further, the soil below biocrusts (1–5 cm) at one agroecosystem had 44% more microbial biomass C and a significantly lower MBC:MBN than soil without biocrusts.

Conclusions: Overall, results illustrate these naturally occurring biocrusts have the potential to benefit agroecosystems by enriching soil C and N in the crop rooting zone, indicating the potential for biocrusts to effect overall soil quality and health.
A review on the potentials of using feeds rich in water‐soluble carbohydrates to enhance rumen health and sustainability of dairy cattle production
Authors: Klevenhusen Fenja , Zebeli Qendrim
Published: June 2021

Cows are adapted to degrade structural plant carbohydrates (SC), such as cellulose and hemicelluloses, prevailing in grasses. Yet, the need for energy‐dense diets in many intensive dairy production systems has shifted the dairy cattleʼs diet from SC‐rich to high levels of starch. Feeding of starch‐rich diets increases the risk of ruminal acidosis in cows, and feeding starch in the form of grains intensifies the competition over cereal grains and arable land among different livestock species, as well as between livestock and humans. Besides cellulose and hemicelluloses, grasses are also often rich in water‐soluble carbohydrates (WSC), which comprise mono‐, di‐, oligo‐ and polysaccharides (fructans). Although the ruminal fermentation profile of mono‐ and disaccharides resembles that of starch, the degradation of oligo‐ and polysaccharides is slower, and their fermentation elicits a rather protecting effect on ruminal pH. When harvested in an early phase (i.e. ear emergence), grass hay and silages can reach WSC levels up to 150–200 g kg−1 dry matter and energy levels close to starch‐rich diets, allowing a significantly reduced inclusion of concentrate supplements. By doing so, this will enhance both rumen health and the sustainability of milk production. However, because the WSC are chemically very heterogeneous, the patterns and extent of their ruminal fermentation are difficult to predict without a clear analytical characterization. This review article aims to summarize both the benefits and potentials, as well as the challenges, with respect to using WSC‐rich feedstuffs in the nutrition of dairy cattle and their effects on ruminal fermentation characteristics and milk production. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Beyond the PAR spectra: impact of light quality on the germination, flowering, and metabolite content of Stevia rebaudiana (Bertoni)
Authors: Rengasamy Narendren , Othman Rofina Y , Che Hang S , Harikrishna Jennifer A
Published: June 2021

BACKGROUND

Stevia rebaudiana is a high value crop due to the strong commercial demand for its metabolites (steviol glycosides) but has limited geographical cultivation range. In non‐native environments with different daylength and light quality, Stevia has low germination rates and early flowering resulting in lower biomass and poor yield of the desired metabolites. In this study, artificial lighting with light‐emitting diodes (LEDs) was used to determine if different light quality within and outside of the photosynthetically active radiation (PAR) range can be used to improve germination rates and yields for production of steviol glycosides for the herbal supplement and food industry.

RESULTS

Plants treated with red and blue light at an intensity of 130 μmol m−2 s−1 supplemented with 5% of UV‐A light under a 16‐h photoperiod produced the most desirable overall results with a high rate of germination, low percentage of early flowering, and high yields of dry leaf, stevioside and rebaudioside A, 175 days after planting.

CONCLUSION

While red and blue light combinations are effective for plant growth, the use of supplemental non‐PAR irradiation of UV‐A wavelength significantly and desirably delayed flowering, enhanced germination, biomass, rebaudioside A and stevioside yields, while supplemental green light improved yield of biomass and rebaudioside A, but not stevioside. Overall, the combination of red, blue and UV‐A light resulted in the best overall productivity for Stevia rebaudiana. © 2021 Society of Chemical Industry.
Soil erosion facilitates shrub encroachment in Patagonian herbaceous steppes
Authors: Romero Ovalle Paula Estelí , Bisigato Alejandro Jorge , Campanella María Victoria
Published: June 2021

Previous studies in northeastern Patagonia suggested that, mainly as a consequence of overgrazing by sheep, the herbaceous steppes are being replaced by shrub steppes dominated by Chuquiraga avellanedae as a consequence of shrub encroachment. The herbaceous steppe presents a thick sandy loam to loamy sand A‐horizon lying on a clay‐horizon while the shrub steppe presents the clay‐horizon at or near the soil surface. The thickness reduction of the remaining A‐horizon and the formation of desert pavements are evidence of soil erosion. As previous studies suggested that shrub encroachment co‐occurs with the erosion of the sandy A‐horizon, we hypothesized that shrub encroachment is favored by the presence of an clay‐horizon near the soil surface. We expected that C. avellanedae emergence and establishment would be higher as the clay horizon is closer to the soil surface and the A‐horizon is reduced. We performed field and greenhouse experiments to evaluate seedling emergence and establishment along a gradient of A‐horizon thickness. We found that the presence of a relatively thin sandy layer on the surface had a negative influence on both shrub emergence and establishment. The summer drought was not a critical period for the seedlings. Conversely, the highest seedling mortality took place during late winter in sandy soils, suggesting that these soils are more susceptible to frost heaving than clay soils. In conclusion, soil erosion in the northeastern Patagonian steppes would indirectly facilitate shrub encroachment due to differences in frost heaving susceptibility between sandy and clay soils.
The ratio of triglycerides to high‐density lipoprotein cholesterol is associated with the risk of chronic kidney disease in Korean men
Authors: Kim Joungyoun , Bae Yoon‐Jong , Shin Sang‐Jun , You Hyo‐Sun , Lee Jae‐woo , Kang Hee‐Taik
Published: June 2021

Dyslipidemia is nephrotoxic and can result in the development of chronic kidney disease (CKD). The ratio of triglycerides (TG) to high‐density lipoprotein cholesterol (HDL‐C) (TG/HDL‐C ratio) is well‐correlated with insulin resistance and cardiovascular events. The aim of this study is to examine the association between the TG/HDL‐C ratio and CKD in Korean adults. This study was retrospectively designed based on the National Health Insurance Service‐National Health Screening cohort. Seventy three thousand and fifty‐two participants aged between 40 and 79 years old at baseline (2009–2010) were included in the final analyses. The study population was classified into three tertile groups (T1, T2, and T3) according to the TG/HDL‐C ratio by sex. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for CKD were calculated using Cox proportional hazard regression models. The median follow‐up duration was 5.9 years. Higher tertile groups of the TG/HDL‐C ratio had lower estimated glomerular filtration rates in both sexes. The cumulative incidence of CKD of T1, T2, and T3was 11.89%, 12.90%, and 12.91%, respectively, in men and 10.17%, 10.61%, and 14.87%, respectively, in women (allpvalues < 0.001). Compared with T1of the TG/HDL‐C ratio, the HRs (95% CIs) of T2and T3for CKD were 1.212 (1.118–1.315) and 1.183 (1.087–1.287), respectively, in men and 0.895 (0.806–0.994) and 1.038 (0.937–1.150), respectively, in women after being fully adjusted. Higher TG/HDL‐C ratios were positively associated with CKD development in men, while middle levels of TG/HDL ratios reduced the CKD incidence in women.
Clinical Utility of 18F‐APN‐1607 Tau PET Imaging in Patients with Progressive Supranuclear Palsy
Authors: Li Ling , Liu Feng‐Tao , Li Ming , Lu Jia‐Ying , Sun Yi‐Min , Liang Xiaoniu , Bao Weiqi , Chen Qi‐Si , Li Xin‐Yi , Zhou Xin‐Yue , Guan Yihui , Wu Jian‐Jun , Yen Tzu‐Chen , Jang Ming‐Kuei , Luo Jian‐Feng , Wang Jian , Zuo Chuantao ,   the Progressive Supranuclear Palsy Neuroimage Initiative (PSPNI)
Published: June 2021

Background

18F‐APN‐1607 is a novel tau PET tracer characterized by high binding affinity for 3‐ and 4‐repeat tau deposits. Whether 18F‐APN‐1607 PET imaging is clinically useful in PSP remains unclear.

Objectives

The objective of this study was to investigate the clinical utility of 18F‐APN‐1607 PET in the diagnosis, differential diagnosis, and assessment of disease severity in patients with PSP.

Methods

We enrolled 3 groups consisting of patients with PSP (n = 20), patients with α‐synucleinopathies (MSA with predominant parkinsonism, n = 7; PD, n = 10), and age‐ and sex‐matched healthy controls (n = 13). The binding patterns of 18F‐APN‐1607 in PET/CT imaging were investigated. Regional standardized uptake ratios were compared across groups and examined in relation to their utility in the differential diagnosis of PSP versus α‐synucleinopathies. Finally, the relationships between clinical severity scores and 18F‐APN‐1607 uptake were investigated after adjustment for age, sex, and disease duration.

Results

Compared with healthy controls, patients with PSP showed increased 18F‐APN‐1607 binding in several subcortical regions, including the striatum, putamen, globus pallidus, thalamus, subthalamic nucleus, midbrain, tegmentum, substantia nigra, pontine base, red nucleus, raphe nuclei, and locus coeruleus. We identified specific regions that were capable of distinguishing PSP from α‐synucleinopathies. The severity of PSP was positively correlated with the amount of 18F‐APN‐1607 uptake in the subthalamic nucleus, midbrain, substantia nigra, red nucleus, pontine base, and raphe nuclei.

Conclusions

18F‐APN‐1607 PET imaging holds promise for the diagnosis, differential diagnosis, and assessment of disease severity in patients with PSP. © 2021 International Parkinson and Movement Disorder Society
A feasibility study on deep learning‐based individualized 3D dose distribution prediction
Authors: Ma Jianhui , Nguyen Dan , Bai Ti , Folkerts Michael , Jia Xun , Lu Weiguo , Zhou Linghong , Jiang Steve
Published: June 2021

Purpose

Radiation therapy treatment planning is a trial‐and‐error, often time‐consuming process. An approximately optimal dose distribution corresponding to a specific patient's anatomy can be predicted by using pre‐trained deep learning (DL) models. However, dose distributions are often optimized based not only on patient‐specific anatomy but also on physicians’ preferred trade‐offs between planning target volume (PTV) coverage and organ at risk (OAR) sparing or among different OARs. Therefore, it is desirable to allow physicians to fine‐tune the dose distribution predicted based on patient anatomy. In this work, we developed a DL model to predict the individualized 3D dose distributions by using not only the patient's anatomy but also the desired PTV/OAR trade‐offs, as represented by a dose volume histogram (DVH), as inputs.

Methods

In this work, we developed a modified U‐Net network to predict the 3D dose distribution by using patient PTV/OAR masks and the desired DVH as inputs. The desired DVH, fine‐tuned by physicians from the initially predicted DVH, is first projected onto the Pareto surface, then converted into a vector, and then concatenated with feature maps encoded from the PTV/OAR masks. The network output for training is the dose distribution corresponding to the Pareto optimal DVH. The training/validation datasets contain 77 prostate cancer patients, and the testing dataset has 20 patients.

Results

The trained model can predict a 3D dose distribution that is approximately Pareto optimal while having the DVH closest to the input desired DVH. We calculated the difference between the predicted dose distribution and the optimized dose distribution that has a DVH closest to the desired one for the PTV and for all OARs as a quantitative evaluation. The largest absolute error in mean dose was about 3.6% of the prescription dose, and the largest absolute error in the maximum dose was about 2.0% of the prescription dose.

Conclusions

In this feasibility study, we have developed a 3D U‐Net model with the patient's anatomy and the desired DVH curves as inputs to predict an individualized 3D dose distribution that is approximately Pareto optimal while having the DVH closest to the desired one. The predicted dose distributions can be used as references for dosimetrists and physicians to rapidly develop a clinically acceptable treatment plan.
The multifacility center problems with random demand weights
Authors: Berman Oded , Wang Jiamin
Published: June 2021

We study two p‐center models on a network with probabilistic demand weights. In the first, which is called the maximum probability p‐center problem, the objective is to maximize the probability that the maximum demand‐weighted distance between the demand and the open facilities does not exceed a given threshold value. In the second, referred to as the β‐VaR p‐center problem, the objective is to minimize the value‐at‐risk of the maximum demand‐weighted distance with a pre‐selected confidence level. It is shown that both models are NP‐hard. We develop algorithms for solving the two models and conduct computational experiments to compare their performance. We recommend that the branch and bound algorithm be applied to solve the first model, and an ensemble optimization method to solve the second model. The solution approaches presented can be easily extended to the case where the random demand weights are not independent.
Extraskeletal Ewing sarcoma in children, adolescents, and young adults. An analysis of three prospective studies of the Cooperative Weichteilsarkomstudiengruppe (CWS)
Authors: Koscielniak Ewa , Sparber‐Sauer Monika , Scheer Monika , Vokuhl Christian , Kazanowska Bernarda , Ladenstein Ruth , Niggli Felix , Ljungman Gustaf , Paulussen Michael , Bielack Stefan S. , Seitz Guido , Fuchs Joerg , Hallmen Erika , Klingebiel Thomas , on behalf of the CWS Study Group
Published: June 2021

Background

We have analyzed the outcome of patients with localized extraskeletal Ewing sarcoma (EES) treated in three consecutive Cooperative Weichteilsarkomstudiengruppe (CWS) soft tissue sarcoma (STS) studies: CWS‐91, CWS‐96, and CWS‐2002P.

Methods

Patients were treated in CWS‐91 with four‐ (vincristine, dactinomycin, doxorubicin, and ifosfamide [VAIA] or cyclophosphamide [VACA II]) or five‐drug (+etoposide [EVAIA]) cycles, in CWS‐96 they were randomly assigned to receive VAIA or CEVAIE (+carboplatin and etoposide), and in CWS‐2002P with VAIA III plus optional maintenance therapy (MT) with cyclophosphamide and vinblastine. Local therapy consisted of resection and/or radiotherapy (RT).

Results

Two hundred forty‐three patients fulfilled the eligibility criteria. The 5‐year event‐free survival (EFS) and overall survival (OS) were 63% (95% confidence interval [CI] 57–69) and 73% (95% CI 67–79), respectively. The 5‐year EFS by study was 64% (95% CI 54–74) in CWS‐91, 57% (95% CI 48–66) in CWS‐96, and 79% (95% CI 67–91) in CWS‐2002P (n.s.). The 5‐year OS was 72% (95% CI 62–82) in CWS‐91, 70% (95% CI 61–79) in CWS‐96, and 86% (95% CI 76–96) in CWS‐2002P (n.s.). In CWS‐96, 5‐year EFS and OS in the VAIA arm versus the CEVAIE were 65% (95% CI 52–81) versus 55% (95% CI 39–76) log‐rank p = .13, and 85% (95% CI 75–96) versus 61% (95% CI 45–82), log‐rank p = .09.

Conclusion

Our analysis provides interesting information on the treatment and specificities of EES, which can be useful for a better understanding of this rare entity and should be considered in the development of future clinical trials for Ewing sarcoma defined as FET–ETS fusion positive tumors.
Triphenylphosphine‐containing microcapsules fabricated from Pickering emulsions as a thermal latent curing accelerator for an epoxy/anhydride system
Authors: Gou Haolan , Zhang Bowen , Wei Wei , Fei Xiaoma , Li Xiaojie , Liu Xiaoya
Published: June 2021

Latent curing accelerators are essential for application to one‐component epoxy systems in various industries, such as coatings, adhesives and electronic packaging. Herein, we developed organic–inorganic hybrid microcapsules encapsulating triphenylphosphine (TPP) by Pickering emulsion polymerization of styrene and methoxyethyl methacrylate with dimethoxydiphenylsilane‐modified silica nanoparticles as emulsifiers. The microcapsules were further surface‐modified by epoxy silane and employed as a thermal latent curing accelerator for an epoxy/anhydride system. Good dispersibility and interfacial bonding of the hybrid microcapsules with the resin matrix were observed. Compared with TPP, the microcapsule‐type accelerator endowed the one‐component epoxy curing system with significantly enhanced storage stability at room temperature of 25 °C (a pot life of 20 days) and a comparable curing activity at high temperature. The activity of the encapsulated accelerator can be blocked and released rapidly and effectively with increasing temperature to trigger the segmental motion of the polymeric microcapsules. Furthermore, the addition of microcapsules increased the glass transition temperature and thermal stability of the epoxy thermosets owing to the organic–inorganic hybrid character. Moreover, the toughness of the cured resin was also improved. Therefore, the latent curing accelerator demonstrated a promising prospect for application in high‐performance one‐pot epoxy formulations. © 2021 Society of Industrial Chemistry.
Understanding dispersity control in photo‐atom transfer radical polymerization: Effect of degree of polymerization and kinetic evaluation
Authors: Rolland Manon , Lohmann Victoria , Whitfield Richard , Truong Nghia P. , Anastasaki Athina
Published: June 2021

In photo‐atom transfer radical polymerization (ATRP), dispersity can be efficiently controlled by varying the deactivator concentration. In this work, we provide mechanistic insight into dispersity‐controlled photo‐ATRP by conducting detailed kinetics under a range of conditions. For the lower dispersity polymers, a conventional first‐order kinetic profile was observed accompanied by a linear evolution of number average molecular weight (Mn) with conversion while the reactions reached moderate to high conversions (between 66% and 93%). Whereas, when polymers of high dispersity were targeted, the Mn remained relatively constant throughout the polymerization and the reactions ceased at less than 50% of conversion. In particular, for Ð = 1.84, a significant deviation between theoretical and experimental molecular weights was evident. This deviation was unambiguously attributed to slow initiation as indicated by 1H NMR, where significant percentages of unreacted initiator were observed. Importantly, the addition of ligand at the polymerization plateau re‐initiated the polymerization and led to the complete consumption of the unreacted initiator, thus enabling the synthesis of one‐pot diblock copolymers. We subsequently evaluated the effect of the degree of polymerization (DP) on the obtained dispersity when a constant catalyst ratio was maintained. Based on the interpolation of those experiments results, we could predict experimental conditions for any desirable DPs and dispersities.
Recent development on bio‐based thermosetting resins
Authors: Liu Jingkai , Zhang Liyue , Shun Wuliuyi , Dai Jinyue , Peng Yunyan , Liu Xiaoqing
Published: June 2021

Due to the rapid depletion of crude oil and serious environmental pollution, the synthesis of polymers from renewable resource is becoming more and more important. Up to now, a great variety of biomass and bio‐based platform compounds have been taken to prepare the polymers. However, as two representative thermosetting resins, epoxy and benzoxazine resin derived from renewable feedstocks only obtain limited attention compared with the popular bio‐based plastics, including PLA, PBAT and PHBV etc. The reason might be that the properties of previously reported thermosetting resins directly obtained from biomass are usually unsatisfied, and their application fields are limited. In this paper, the latest development on the synthesis of high‐performance bio‐based epoxy and polybenzoxazine resins are reviewed. In addition, to further broaden their applications, the functionalization strategies are also summarized. The objective of this work is to help us fully aware the present situation of bio‐based thermosetting resins and then promote their faster development, especially practical application.
Electrostatics and water occlusion regulate covalently‐bound flavin mononucleotide cofactors of Vibrio cholerae respiratory complex NQR
Authors: Willow Soohaeng Yoo , Yuan Ming , Juárez Oscar , Minh David D. L.
Published: June 2021

Proteins like NADH:ubiquinone oxidoreductase (NQR), an essential enzyme and ion pump in the physiology of several pathogenic bacteria, tightly regulate the redox properties of their cofactors. Although flavin mononucleotide (FMN) is fully reduced in aqueous solution, FMN in subunits B and C of NQR exclusively undergo one‐electron transitions during its catalytic cycle. Here, we perform ab initio calculations and molecular dynamics simulations to elucidate the mechanisms that regulate the redox state of FMN in NQR. QM/MM calculations show that binding site electrostatics disfavor anionic forms of FMNH2, but permit a neutral form of the fully reduced flavin. The potential energy surface is unaffected by covalent bonding between FMN and threonine. Molecular dynamics simulations show that the FMN binding sites are inaccessible by water, suggesting that further reductions of the cofactors are limited or prohibited by the availability of water and other proton donors. These findings provide a deeper understanding of the mechanisms used by NQR to regulate electron transfer through the cofactors and perform its physiologic role. They also provide the first, to our knowledge, evidence of the simple concept that proteins regulate flavin redox states via water occlusion.
Licarin A, a neolignan isolated from Nectandra oppositifolia Nees & Mart. (Lauraceae), exhibited moderate preclinical efficacy against Schistosoma mansoni infection
Authors: Mengarda Ana C. , Silva Marcos P. , Cirino Maria E. , Morais Thiago R. , Conserva Geanne A. A. , Lago João Henrique G. , de Moraes Josué
Published: June 2021

Schistosomiasis is a widespread human parasitic disease currently affecting over 200 million people, particularly in poor communities. Chemotherapy for schistosomiasis relies exclusively on praziquantel (PZQ). Previous studies have shown that licarin A (LIC‐A), a dihydrobenzofuran neolignan, exhibited in vitro antiparasitic activity against Schistosoma mansoni adult worms. This study aimed to investigate the potential of LIC‐A, isolated as main metabolite from leaves of Nectandra oppositifolia Nees & Mart. (Lauraceae), as an antischistosomal agent orally active in schistosomiasis animal model. PZQ was used as a reference compound. As result, LIC‐A showed, at a single dose of 400 mg/kg, to be able to partially cure infected mice (worm burden reductions of ~50%). Parasite eggs, that are responsible for a variety of pathologies and transmission of schistosomiasis, were also moderately inhibited by LIC‐A (egg burden reductions of ~50%–60%). Furthermore, it was observed that LIC‐A achieved a slight reduction of hepatomegaly and splenomegaly. Collectively, although LIC‐A was partially active when administered orally, these results give support for the antiparasitic potential LIC‐A as lead compound for novel antischistosomal agent.
Toward Fully‐Fledged Quantum and Classical Communication Over Deployed Fiber with Up‐Conversion Module
Authors: Bacco Davide , Vagniluca Ilaria , Cozzolino Daniele , Friis Søren M. M. , Høgstedt Lasse , Giudice Andrea , Calonico Davide , Cataliotti Francesco Saverio , Rottwitt Karsten , Zavatta Alessandro
Published: June 2021

Quantum key distribution (QKD), the distribution of quantum secured keys useful for data encryption, is expected to have a crucial impact in the next decades. However, despite the notable achievements accomplished in the last 20 years, many practical and serious challenges are limiting the full deployment of this novel quantum technology in the current telecommunication infrastructures. In particular, the co‐propagation of quantum signals and high‐speed data traffic within the same optical fiber is not completely resolved, due to the intrinsic noise caused by the high‐intensity of the classical signals. As a consequence, current co‐propagation schemes limit the amount of classical optical power in order to reduce the overall link noise. However, this ad‐hoc solution restrains the range of possibilities for a large scale QKD deployment. Here, a new method, based on up‐conversion assisted receiver, for co‐propagating classical light and QKD signals is proposed and demonstrated. In addition, its performances are compared with an off‐the‐shelf quantum receiver, equipped with a standard single‐photon detector, over different lengths of an installed fiber link. The authors' proposal exhibits higher tolerance for noise in comparison to the standard receiver, thus enabling the distribution of secret keys in the condition of 4 dB‐higher classical power.
Dyspnoea with progressive “idiopathic” pulmonary fibrosis
Authors: Puri Chahat , Harish Vignesh , Rhee Kyunghoon , Slack Donald F.
Published: June 2021

Telomeres are repetitive nucleotide sequences that prevent chromosomal shortening in cell replication. Short telomeres have been implicated in the pathogenesis of interstitial lung disease. Patients with short telomere related pulmonary fibrosis can have computed tomography (CT) findings inconsistent with pro‐typical usual interstitial pneumonia/idiopathic pulmonary fibrosis (UIP/IPF) pattern. They can have rapid progression and overall worse prognosis. Antifibrotic drugs, like pirfenidone, can be used to slow the progression of disease, but there is conflicting data in patients with Telomerase reverse transcriptase/Telomerase RNA component (TERT/TERC) mutations, hence genetic testing plays an important role in determining the therapeutic options. These patients should be referred for lung transplantation early. We present a case of rapidly progressive pulmonary fibrosis associated with short telomere.
Entrepreneurship at a crossroads: Meta‐analysis as a foundation and path forward
Authors: Combs James G. , Crook T. Russell , Ketchen David J. , Wright Mike
Published: June 2021

Research Summary

This special issue on “Advancing Entrepreneurship Research through Meta‐analysis” was commissioned in the belief that many entrepreneurship research topics have reached a crossroads. As a maturing, dynamic, and growing field, researchers are generating ever more empirical evidence regarding the field's central questions. Researchers can continue down this road, but for many topics, it seems time to pause and take stock of what has been learned—a task meta‐analysis was created to accomplish. We describe how the special issue articles accumulate and clarify what is known about important questions. Two of the studies highlight that entrepreneurial organizations are in fact different from other organizational settings, and all lay foundations that open new avenues for inquiry. We conclude by summarizing the types of questions meta‐analysis can help answer going forward and the advanced meta‐analytic techniques that are becoming increasingly important for answering such questions.

Managerial Summary

This special issue was commissioned because many entrepreneurship research streams contain mixed evidence about the nature of important relationships. Such a situation makes it difficult for entrepreneurs to leverage academic findings as they make decisions and for researchers to understand what is known. Meta‐analysis is a set of statistical tools that allows for the reconciliation of evidence that points in different directions and thereby provides actionable guidance for entrepreneurs and a solid foundation for researchers to build on. This introduction summarizes the special issue articles and describes their contributions. One key overall implication that arises from this collection of studies is that much of what works in traditional organizations is likely to work quite differently in entrepreneurial contexts.
The Spectrum of Skin-Related Conditions in Primary Care During 2015–2019–A Finnish Nationwide Database Study
Authors: Salava A. , Oker-Blom A. , Remitz A.
Published: June 2021

Background

Skin-related conditions are the frequent cause of doctors’ consultations in primary care.

Methods

Based on nationwide data bank information of the Finnish Institute for Health and Welfare, we analysed the 20 most frequent main diagnoses for each ICD-10 category of all general practitioners’ visits in the public health care in Finland over the years 2015–2019.

Results

The total amount of doctor’s visits was 19 204 613 of which 1 489 228 consultations (7.80%) had a skin-related condition as the main diagnosis. The most frequent skin-related conditions were eczematous eruptions, bacterial skin infections and benign skin neoplasms accounting for 749 351 consultations (50.32%). The spectrum of skin-related conditions was diverse, with a large quantity of rarer diagnoses. Some diagnoses showed significant proportional changes.

Conclusions

The results demonstrate that a limited amount of conditions comprises most of the skin-related consultations in primary care in Finland. Undergraduate education in dermatology should concentrate on the most frequent conditions seen by general practitioners, but also address the wide range of skin problems.
Software defect prediction with imbalanced distribution by radius‐synthetic minority over‐sampling technique
Authors: Guo Shikai , Dong Jian , Li Hui , Wang Jiahui
Published: June 2021

Software defect prediction, which can identify the defect‐prone modules, is an effective technology to ensure the quality of software products. Due to the importance in software maintenance, many learning‐based software defect prediction models are presented in recent years. Actually, the defects usually occupy a very small proportions in software source codes; thus, the imbalanced distributions between defect‐prone modules and non‐defect‐prone modules increase the learning difficulty of the classification task. To address this issue, we present a random over‐sampling mechanism used to generate minority‐class samples from high‐dimensional sampling space to deal with the imbalanced distributions in software defect prediction, in which two constraints are applied to provide a robust way to generate new synthetic samples, that is, scaling the random over‐sampling scope to a reasonable area and distinguishing the majority‐class samples in a critical region. Based on nine open datasets of software projects, we experimentally verify that our presented method is effective on predict the defect‐prone modules, and the effect is superior to the traditional imbalanced processing methods.
Characteristic function and Laplace transform‐based tests for exponentiality in the presence of random right censoring
Authors: Bothma Elzanie , Allison James Samuel , Cockeran Marike , Visagie Izak Jakobus Henning
Published: June 2021

In this paper, the composite hypothesis that lifetimes follow an exponential distribution is tested based on observed randomly right censored data. Testing this hypothesis is complicated by the presence of this censoring, due to the fact that not all lifetimes are observed. To account for this complication, we propose modifications to tests based on the empirical characteristic function and Laplace transform. In the full sample case, these empirical functions can be expressed as integrals with respect to the empirical distribution function of the lifetimes. We propose replacing this estimate of the distribution function by the Kaplan–Meier estimate. The resulting test statistics can be expressed in easily calculable forms in terms of summations of functionals of the observed data. Additionally, a general framework for goodness‐of‐fit testing, in the presence of random right censoring, is outlined. A Monte Carlo study is performed, the results of which indicate that the newly modified tests generally outperform the existing tests. A practical application, concerning initial remission times of leukaemia patients, is discussed along with some concluding remarks and avenues for future research.
Performance of a targeted cell‐free DNA prenatal test for 22q11.2 deletion in a large clinical cohort
Authors: Bevilacqua E. , Jani J. C. , Chaoui R. , Suk E.‐K. A. , Palma‐Dias R. , Ko T.‐M. , Warsof S. , Stokowski R. , Jones K. J. , Grati F. R. , Schmid M.
Published: June 2021

Objective

22q11.2 deletion is more common than trisomies 18 and 13 combined, yet no routine approach to prenatal screening for this microdeletion has been established. This study evaluated the clinical sensitivity and specificity of a targeted cell‐free DNA (cfDNA) test to screen for fetal 22q11.2 deletion in a large cohort, using blinded analysis of prospectively enrolled pregnancies and stored clinical samples.

Methods

In order to ensure that the analysis included a meaningful number of cases with fetal 22q11.2 deletion, maternal plasma samples were obtained by prospective, multicenter enrolment of pregnancies with a fetal cardiac abnormality and from stored clinical samples from a research sample bank. Fetal genetic status, as evaluated by microarray analysis, karyotyping with fluorescence in‐situ hybridization or a comparable test, was available for all cases. Samples were processed as described previously for the Harmony prenatal test, with the addition of DANSR (Digital Analysis of Selected Regions) assays targeting the 3.0‐Mb region of 22q11.2 associated with 22q11.2 deletion syndrome. Operators were blinded to fetal genetic status. Sensitivity and specificity of the cfDNA test for 22q11.2 deletion were calculated based on concordance between the cfDNA result and fetal genotype.

Results

The final study group consisted of 735 clinical samples, including 358 from prospectively enrolled pregnancies and 377 stored clinical samples. Of 46 maternal plasma samples from pregnancies with a 22q11.2 deletion, ranging in size from 1.25 to 3.25 Mb, 32 had a cfDNA result indicating a high probability of 22q11.2 deletion (sensitivity, 69.6% (95% CI, 55.2–80.9%)). All 689 maternal plasma samples without a 22q11.2 deletion were classified correctly by the cfDNA test as having no evidence of a 22q11.2 deletion (specificity, 100% (95% CI, 99.5–100%)).

Conclusions

The results of this large‐scale prospective clinical evaluation of the sensitivity and specificity of a targeted cfDNA test for fetal 22q11.2 deletion demonstrate that this test can detect the common and smaller, nested 22q11.2 deletions with a low (0–0.5%) false‐positive rate. Although the positive predictive value (PPV) observed in this study population was 100%, the expected PPV in the general pregnant population is estimated to be 12.2% at 99.5% specificity and 41.1% at 99.9% specificity. The use of this cfDNA test to screen for 22q11.2 deletion could enhance identification of pregnancies at risk for 22q11.2 deletion syndrome without significantly increasing the likelihood of maternal anxiety and unnecessary invasive procedures related to a false‐positive result. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Responses of submerged macrophytes Vallisneria natans and epiphytic biofilm to floating plants Eichhornia crassipes in eutrophic water
Authors: Zhang Chen , Li Qi , Zhang Liu , Zhang Jibiao
Published: June 2021

The degeneration of submerged macrophytes and the invasion of Eichhornia crassipes (E. crassipes) destroyed the balance of aquatic ecosystems environments. In this study, responses of Vallisneria natans (V. natans) and the leaf‐epiphytic biofilms to E. crassipes were analyzed to provide a technical scheme for V. natans restoration and E. crassipes control in eutrophic water. The results showed that a significant improvement of water quality achieved in 1100 ind·m−2 E. crassipes density group and TN removal rate reached 63.53%. The presence of E. crassipes changed the morphological characteristics of V. natans, which stimulated the adaptive mechanisms via promotion of shoot height and root length. Concentrations of the antioxidant enzymes, peroxidase, superoxide dismutase, and catalase in the V. natans leaves remained stable. But E. crassipes greatly increased the microbial diversity on V. natans leave biofilms. Furthermore, the greatest richness in bacterial community diversity was observed at 700, 1100, and 1200 ind·m−2 E. crassipes densities in heatmap, which was beneficial to the stability of the water ecological environment. These results showed that the combination of V. natans with E. crassipes of 1100 ind m−2 providing more favorable conditions for the growth and restoration of submerged macrophytes and improve the water quality.

Practitioner Points

The responses of submerged macrophytes to floating plants were studied.

The optimal density of Eichhornia crassipes was 1100 ind m−2.

The biofilm microbial community changed in response to Eichhornia crassipes.