bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk of age‐related macular degeneration in aspirin users and non‐aspirin users: A population‐based cohort study in Taiwan
Authors: Lee Wan‐Ju Annabelle , Yang Yea‐Huei Kao , Cheng Ching‐Lan
Published: October 2020

Background

The association between cardioprotective aspirin and risk of age‐related macular degeneration (AMD) is still controversial up to date. We aimed to analyze the risk of AMD between aspirin users and non‐aspirin users.

Method

This was a retrospective cohort study by using claims data from the National Health Insurance Research Database. Patients aged more than 45 years old who initiated aspirin during 2002 to 2012 were followed till 2013. We first selected an age and sex‐matched cohort, then identified aspirin users and non‐aspirin users as propensity score‐matched cohort. Cox proportional hazard regression model was applied to compare their hazards and 95% confidence intervals. Incidence of newly developed AMD, neovascular AMD, and other‐AMD was calculated.

Results

We identified 204 085 regular aspirin users and 478 048 non‐aspirin users from our datasets. The univariate HR was 2.85 (95% CI, 2.75‐2.96), and the multivariate HR was 2.54 (95% CI, 2.44‐2.65). In the PS‐matched cohort, the HR was 2.38 (95% CI, 2.25‐2.52). The incidence of aspirin users for AMD risk was 11.95 per 1000 person‐year, while the incidence of non‐aspirin users was only 3.92 per 1000 person‐year.

Conclusion

Patients with regular use of aspirin had higher risk in developing AMD compared to non‐aspirin users and suggest to have regular visual acuity and funduscopic examination.
Validation of venous thromboembolism diagnoses in patients receiving rivaroxaban or warfarin in The Health Improvement Network
Authors: Ruigómez Ana , Brobert Gunnar , Vora Pareen , García Rodríguez Luis A.
Published: October 2020

Purpose

To describe the effect that validation of venous thromboembolism (VTE) coded entries in the health improvement network (THIN) has on incidence rates of VTE among a cohort of rivaroxaban/warfarin users.

Methods

Among 36 701 individuals with a first prescription for rivaroxaban/warfarin between 2012 and 2015, we performed a two‐step VTE case identification process followed by a two‐step case validation process involving manual review of patient records. A valid case required a coded entry for VTE at some point after their first rivaroxaban/warfarin prescription with evidence of referral/hospitalization either as a coded entry or entered as free text. Positive predictive values (PPVs) with 95% confidence intervals (CIs) were calculated using validated cases as the gold standard. Incidence rates were calculated per 1000 person‐years with 95% CIs.

Results

We identified 2166 patients with a coded entry of VTE after their initial rivaroxaban/warfarin prescription; incidence rate of 45.31 per 1000 person‐years (95% CI: 43.49‐47.22). After manual review of patient records including the free text, there were 712 incident VTE cases; incidence rate of 14.90 per 1000 person‐years (95% CI: 13.85‐16.02). The PPV for coded entries of VTE alone was 32.9%, and the PPV for coded entries of VTE with a coded entry of referral/hospitalization was 39.8%; this increased to 69.6% after manual review of coded clinical entries in patient records.

Conclusions

Among rivaroxaban/warfarin users in THIN, valid VTE case identification requires manual review of patient records including the free text to prevent outcome misclassification and substantial overestimation of VTE incidence rates.
The Role of Earlier Receipt of a Lower Limb Prosthesis on Emergency Department Utilization
Authors: Miller Taavy A. , Paul Rajib , Forthofer Melinda , Wurdeman Shane R.
Published: October 2020

Introduction

Adverse events after a lower limb amputation (LLA) can negatively affect the rehabilitation process and may lead to emergency department (ED) visits. Earlier receipt of a prosthesis, as compared to delayed or not receiving a prosthesis, may decrease or moderate the risk of increased ED utilization. In addition, adverse events (ie, fall‐related injury [FRI]) may be associated with increased health care utilization as measured by ED use. The implication of the timing of prosthesis provision after amputation and reduced ED use is not well established. Obtaining data about ED utilization early post‐LLA could assist the rehabilitation team in ensuring timely and appropriate access to improve outcomes.

Objective

To determine the role that timing of prosthesis receipt has in ED utilization and the association of fall/FRI with health care utilization.

Design

Retrospective observational cohort using commercial claims data. A logistic regression model was used to assess factors that influence ED utilization post‐LLA.

Setting

Watson/Truven administrative database 2014 to 2016.

Participants

The study sample consisted of 510 adults age 18 to 64 years with continuous enrollment for 3 years.

Interventions

Independent variables included age, sex, diabetes status, amputation level, fall diagnosis, and prosthesis receipt. Fall was defined as presence of a diagnosis code in any outpatient procedure after the amputation date.

Main Outcome Measure

ED use after amputation was defined as the presence of procedure codes that billed for ED services (99281 to 99285).

Results

Individuals who receive a prosthesis early, within 0 to 3 months, post‐LLA were 48% (odds ratio [OR] 0.52, 95% confidence interval [CI] 0.28 to 0.97) less likely to use the ED compared to those who did not receive a prosthesis. Individuals who experienced a fall/FRI had 2.8 (OR 2.86, 95% CI 1.23 to 6.66) times the odds of ED utilization.

Conclusion

Receipt of a prosthesis reduces the risk of ED use. The current study underscores the value of prostheses during the rehabilitation process after LLA.
Dual catalysis with an N‐heterocyclic carbene and a Lewis acid: Thermally latent precatalyst for the polymerization of ε‐caprolactam
Authors: Altmann Hagen J. , Steinmann Mark , Elser Iris , Benedikter Mathis J. , Naumann Stefan , Buchmeiser Michael R.
Published: October 2020

So far, the earlier reported strong correlation between basicity of an N‐heterocyclic carbene (NHC) and its reactivity in poly(ε‐caprolactam) (PA6) synthesis resulted in a substantial limitation of applicable carbenes. Here, to overcome this issue, 1,3‐dimethylimidazolium‐2‐carboxylate, an easily accessible, air and moisture‐stable NHC, was applied as thermally latent initiator. In order to compensate for its low basicity, reactivity was enhanced by the addition of both a Lewis acid and an activator to ease the initial polymerization step. The resulting mixtures of ε‐caprolactam, the CO2‐protected NHC, a Lewis acid and N‐acylazepan‐2‐one constitute homogeneous, thermally fully latent “single‐component” blends for the anionic polymerization‐based synthesis of PA6. They can be stored both in the liquid and solid state for days and months, respectively, without any loss in activity. The role of the Lewis acid as well as technical implications of the prolonged pot‐times are discussed.
Can targeting information on cancer‐related psychosocial services by male gender and rurality improve attitude to service use in this difficult‐to‐engage population?
Authors: Harrison Nathan J. , Gunn Kate M. , Wilson Carlene J.
Published: October 2020

Objective

Rural men affected by cancer are difficult to engage in psychosocial support services. This exploratory study tested whether exposure to printed brochures describing services, distinguished by a focus on rural men affected by cancer, resulted in more positive help‐seeking attitudes than exposure to material focused on rural location only or generic cancer support material.

Methods

Targeted versions of a South Australian Cancer Council service brochure were developed to enhance cultural appropriateness, consistent with the Elaboration Likelihood Model. Rural men affected by cancer were recruited via supportive accommodation and randomized to receive one of the three brochures. The primary outcome was positive attitude to help‐seeking at post‐test (between 1 and 2 days). Negative attitudes to help‐seeking, intention to seek help, perceived isolation, and service use were secondary outcomes; perceived information relevance at immediate post‐test was also measured.

Results

Analysis (N = 114) indicated no detectable group differences (rurality/male gender, n = 33; rurality, n = 41; control, n = 40) on primary or secondary outcome measures (p > 0.05). Participants' existing service use was high, due to the recruitment methods. Support service information was primarily sourced from other people (e.g., friends/family, 22.22%; medical professionals, 27.27%).

Conclusions

Existing service use rates suggest that ceiling effects obscured any potential benefit from demographic targeting of materials. Further research should consider building understanding about the acceptability of targeting techniques in this population, replication with materials designed with greater consumer input, and employ samples recruited outside a support service.
Utilizing the TTOP model to understand spatial permafrost temperature variability in a High Arctic landscape, Cape Bounty, Nunavut, Canada
Authors: Garibaldi Madeleine C. , Bonnaventure Philip P. , Lamoureux Scott F.
Published: October 2020

Ground surface and permafrost temperatures in the High Arctic are often considered homogeneous especially when viewed at the scale of climate and environmental models. However, this is generally incorrect due to highly variable, topographically redistributed snow cover, which generates a substantial degree of ground thermal heterogeneity. The objective of this study is to describe and spatially model the variability in the ground thermal regime within the Cape Bounty Arctic Watershed Observatory (CBAWO), Nunavut, Canada, using the TTOP model, for current conditions in addition to a series of future climate change scenarios. While observed air temperature was mostly uniform, annual mean ground surface and permafrost temperatures across the paired watersheds were estimated to range between −3.8 to −13.8°C and −3.9 to −14°C, respectively, similar to the −5 to −15°C magnitude and range identified from boreholes across the High Arctic. The spatial models showed higher ground surface temperatures in topographic hollows (slope bases and stream channels), and lower temperatures in areas of topographic prominence (hilltops and plateaus) following the spatial pattern of snow accumulation and redistribution. Under projected climate change, the models predicted areas with the coldest permafrost to have the largest magnitude of warming (about 9°C), while areas of warm permafrost became closer to 0°C (warming 4–7°C). This thermal heterogeneity may have implications for ground instability such as permafrost‐related mass movements, hydrological connectivity, biogeochemical cycling, and microbial activity, which influence water quality and contaminant mobility.
A Review of the Catalytic Effects of Lead‐Based Ballistic Modifiers on the Combustion Chemistry of Double Base Propellants
Authors: Warren Lisette R. , Wang Zixuan , Pulham Colin R. , Morrison Carole A.
Published: October 2020

Lead‐based compounds are the current industry‐standard ballistic modifier for double‐base propellants, but there is a pressing need for alternatives as incoming European legislation will soon ban their use. This review article introduces the main concepts and terminologies in the combustion chemistry of double‐base propellants, and critically evaluates the four theories put forward in the literature to account for the ballistic modifier effect, namely (i) photochemical, (ii) chelating/complex, (iii) carbon soot, and (iv) free radical theories. We also review the literature on current trends in ballistic modifier research and note the emerging potential of oxide nanoparticles (in particular Bi2WO6) and Cu/Bi encapsulated in carbon nanotubes as lead‐free ballistic modifier additives.
Using phenology models to estimate insecticide effects on population dynamics: examples from codling moth and obliquebanded leafroller
Authors: Jones Vincent P
Published: October 2020

BACKGROUND

Phenology models based on degree‐days were modified to estimate the effects of insecticide applications on the codling moth,Cydia pomonella (L.), and the obliquebanded leafroller,Choristoneura rosaceana(Harris) (Lepidoptera: Tortricidae). Because the models inherently track stage structure of the population over the course of the season, stage specific mortality can be applied for various durations and intensities allowing the user to simulate different types of pesticides (ovicides, larvicides, organic or conventional materials). The models presented incorporate reproduction, effects of an application on subsequent generations, and the effects of each insecticide by itself as well as the combination of all the treatments. By comparing the treated populations to an untreated control, an estimate of how much the population size is reduced by different treatment programs over the entire season provides a clear assessment of the effectiveness of the treatment program. Simulations for codling moth also allow the insecticide effects to be simulated in conjunction with mating disruption (or not) and simulations for obliquebanded leafroller include the effect of insecticides on both instars 1–3 and 4–6.

RESULTS

The simulations show there are distinct windows of opportunity for management programs, with rather large windows where an insecticide application has only a minor effect on population growth and also shows that intergenerational effects greatly affect optimal timings in subsequent generations.

CONCLUSION

The models are especially useful in assessing current management strategies, testing potential improvements in timings, and evaluating cost savings and reducing non‐target effects.
Distribution of insecticide resistance and molecular mechanisms involved in the West Nile vector Culex pipiens in Morocco
Authors: Arich Soukaina , Assaid Najlaa , Taki Hassan , Weill Mylène , Labbé Pierrick , Sarih M'hammed
Published: October 2020

BACKGROUND

Mosquitoes of the Culex pipiens complex are the vectors of several arboviruses and are thus subjected to insecticide control worldwide. However, overuse of insecticides selects for resistance. While assessing the resistance status of the vectors is required for effective and sustainable disease control, resistance has so far only been sparsely studied in Morocco. In this study, we establish a first countrywide assessment of the levels of resistance to various insecticides and the potential responsible mechanisms involved.

Cx. pipiens larvae were collected from natural populations of five regions of Morocco, and their taxonomic status was determined (molecular forms). The level of their susceptibility to insecticides was assessed by single‐diagnostic‐dose bioassays. Molecular identification of known resistance alleles was investigated to determine the frequency of target‐site mutations.

RESULTS

This study confirms that Moroccan populations are an interbreeding mix of pipiens and molestus forms, with large gene flow for the resistance alleles. We also found that Cx. pipiens mosquitoes are resistant to all insecticide families, all over Morocco: resistance is high for insecticides used in mosquito control, but also present for other pesticides. Resistance alleles are similarly more frequent for mosquito control insecticides. However, their distribution is heterogeneous in the five regions, with significant genetic differentiation between populations, revealing the crucial role of local insecticide treatment practices.

CONCLUSION

This study provides reference countrywide data that highlight the need for further research to refine the distribution of resistance in Morocco and to understand the role of agriculture/urban residuals in its spread. © 2020 Society of Chemical Industry
Temperature‐Dependent Electronic Transport in Non‐Bulk‐Resistance‐Variation Nitrogen‐Doped Cr2Ge2Te6 Phase‐Change Material
Authors: Shuang Yi , Hatayama Shogo , Ando Daisuke , Sutou Yuji
Published: October 2020

The electronic transport mechanism of the nitrogen‐doped Cr2Ge2Te6 (NCrGT) phase‐change material (PCM) is studied, showing almost zero resistivity variation upon phase transition. A similar low‐temperature variable‐range hopping (VRH) behavior in both the amorphous and crystalline phases of the NCrGT PCM is observed by measuring the temperature‐dependent resistivity. At high temperatures above 300 K, the conduction mechanism in the amorphous NCrGT is thermally activated band conduction, while the carrier transport in the crystalline NCrGT is still driven by VRH. Moreover, Hall property measurements reveal a thermally activated carrier in the amorphous NCrGT and mobility‐driven hopping conduction in the crystalline NCrGT at a high temperature range from 300 to 400 K. The conduction mechanism difference between the amorphous and crystalline NCrGT/tungsten (W) contacts is further investigated by measuring the temperature‐dependent I–V characteristics. The conduction in the amorphous NCrGT/W contact is dominated by thermionic‐field emission, while the transport mechanism through the crystalline NCrGT/W interface is controlled by the defect‐assisted tunneling current. Such noticeable conduction mechanism variation results in a large contact resistance contrast in a memory cell.
Comparison of optimal accelerated life tests with competing risks model under exponential distribution
Authors: Fan Tsai‐Hung , Wang Yi‐Fu
Published: October 2020

Accelerated life testing (ALT) is the process of testing products by subjecting them to strict conditions in order to observe more failure data in a short time period. In this study, we compare the methods of two‐level constant‐stress ALT (CSALT) and simple step‐stress ALT (SSALT) based on competing risks of two or more failure modes with independent exponential lifetime distributions. Optimal sample size allocation during CSALT and the optimal stress change‐time in SSALT are considered based on V‐ and D‐optimality , respectively. Under Type‐I censoring, numerical results show that the optimal SSALT outperforms the optimal CSALT in a wide variety of settings. We theoretically also show that the optimal SSALT is better than the optimal CSALT under a set of conditions. A real data example is analyzed to demonstrate the performance of the optimal plans for both ALTs.
Robotic enucleation for oesophageal benign and borderline tumours: Less is more?
Authors: Tribuzi Angela , Bencini Lapo , Paolini Claudia , Di Marino Michele , Coratti Andrea
Published: October 2020

Background

Oesophageal benign to borderline tumours are rare entities, and their optimal treatment strategy remains controversial. Surgical robotic enucleation is an option to optimize their management.

Methods

We prospectively collected data on seven consecutive oesophageal benign to borderline tumours operated robotically over a 4‐year period. Patient baseline characteristics, perioperative outcomes and medium‐term follow‐ups were reviewed and analysed retrospectively.

Results

Two patients underwent a robotic oesophagectomy and five underwent a simple enucleation. These last were the objective of the final analysis. Median operative time was 150 min. Neither deaths nor postoperative complications occurred. Median oral feeding started on postoperative day 3.5. The median postoperative stay was 5 days. Final histopathology confirmed two gastrointestinal stromal tumours, two leiomyomas and one simple cyst.

Conclusions

Robotic enucleation of oesophageal benign to borderline tumours is a feasible procedure in a dedicated oesophageal unit, with optimal perioperative outcomes in a small series of cases with limited follow‐up.
Asymptotic for the cumulative distribution function of the degrees and homomorphism densities for random graphs sampled from a graphon
Authors: Delmas Jean‐François , Dhersin Jean‐Stéphane , Sciauveau Marion
Published: October 2020

We give asymptotics for the cumulative distribution function (CDF) for degrees of large dense random graphs sampled from a graphon. The proof is based on precise asymptotics for binomial random variables. This result is a first step for giving a nonparametric test for identifying the degree function of a large random graph. Replacing the indicator function in the empirical CDF by a smoother function, we get general asymptotic results for functionals of homomorphism densities for partially labeled graphs. This general setting allows to recover recent results on asymptotics for homomorphism densities of sampled graphon.
Two‐stage hybrid learning techniques for bankruptcy prediction*
Authors: Tsai Chih‐Fong
Published: October 2020

Many machine learning‐based techniques have been used for the prediction of bankruptcy. They can be divided into single, ensemble, and hybrid learning techniques. This paper focuses on a two‐stage hybrid learning approach for bankruptcy prediction where, in the first stage, a clustering algorithm is used to perform the instance selection task in order to filter out a certain number of unrepresentative training data. The clustering results output from the first stage are used with a classification algorithm to construct the prediction model. The results of experiments based on five different country datasets show that the best support vector machine (SVM) classifier performance is obtained using instance selection by affinity propagation (AP) and k‐means individually. Moreover, we also find that although the best AP/k‐means and SVM combination is dataset dependent, the criteria for selecting representative training data are specific. This should become a guideline for developing bankruptcy prediction systems based on the hybrid learning approach.
Starch Pasting Properties, and the Effects of Banana Flour and Cassava Flour Addition to Semolina Flour on Starch and Amino Acid Digestion
Authors: Rachman Adetiya , Brennan Margaret A. , Morton James , Brennan Charles S.
Published: October 2020

This study evaluates the proximate composition, amylose, resistant starch, pasting properties, total phenolic content (TPC), antioxidant capacities, and amino acid profiles of banana flour and cassava flour in comparison to semolina flour. Banana flour and cassava flour have a lower protein content (4.54% and 1.41%) but higher total dietary fiber (16.46% and 10.99%) than semolina flour (12.36% and 7.07%, respectively). The two gluten‐free flours have a lower amylopectin content compared to semolina flour. Banana flour shows high nutritional qualities (resistant starch, TPC, and antioxidant capacities) compared to cassava and semolina flours. The amino acid evaluation shows that banana and cassava flours have a better ratio of total essential amino acid to total amino acid (35.37% and 29.95% vs 23.34%) but have lower limiting essential amino acid values (0.98% and 1.51% vs 11.12%) than semolina flour. Understanding the different physicochemical, functional, and nutritional properties of banana and cassava flours helps to inform the development of gluten‐free cereal products based on these flours.
Flexural capacity of steel‐FCB bar‐reinforced coral concrete beams
Authors: Wang Lei , Song Zhaoping , Huang Changshi , Ma Linjian , Fu Feng
Published: October 2020

Steel‐fiber composite bar (SFCB) is a new technique with steel core embedded into the fiber‐reinforced polymer (FRP) bars, which solve the shortcomings of poor ductility and low stiffness of FRP‐reinforced concrete members. Based on the experimental study, flexural behavior of a new type concrete, SFCB bars‐reinforced coral concrete beams, is investigated. The deflection, failure mode, tensile strain, and ultimate flexural capacity of this new type of concrete beam are studied in detail through a series four‐points bending tests. The results show that the failure process of SFCB‐reinforced coral concrete beam can be divided into three main stages: elastic, cracking, and failure. Because exterior layer of SFCB bar is able to continue to withstand tensile stress after its steel core yield, hence, the flexural rigidity and flexural capacity of the beams both increase. The flexural stiffness of SFCB bars‐reinforced coral concrete beams is also increased, and the load‐deflection relation is more or less nonlinear. By using SFCB bars, the stiffness of the beams can be increased by about 20%. However, under high stress state, the relative slip between the carbon fiber and the concrete as well as that between the steel core and the carbon fiber cause tensile stress loss which weakened the flexural resistance of the SFCB bar‐reinforced coral concrete beam. The bonding performance between the round surface steel core and the carbon fiber is obviously weaker than that of the threaded surface steel core, and the steel core slip is more likely to occur under the higher tensile stress. When Using ACI440.1R‐15 and GB50608‐2010 to calculate the flexural capacity of the SFCB beams, the ratios of the theoretical value and the measured value from tests are 1.07 and 1.12, respectively. By introducing two new factors k1 and k2, a formula was developed through modification of the existing ones from ACI440.1R‐15 and GB50608‐2010 to calculate the ultimate flexural capacity of SFCB bar reinforced concrete beam which agrees as high as 93–99% with the experimental results.
Resistance of hydrophobic concrete with different moisture contents to advanced freeze–thaw cycles
Authors: Al‐Kheetan Mazen J. , Al‐Tarawneh Mu'ath , Ghaffar Seyed Hamidreza , Chougan Mehdi , Jweihan Yazeed S. , Rahman Mujib M.
Published: October 2020

This article is aimed at investigating the long‐term performance of three original hydrophobic materials, namely, sodium acetate, fluoropolymer, and silicone resin. Their performance was compared with traditional silane when applied to fully dry concrete, fully saturated concrete, and concrete with 2 and 4% moisture content. A recently developed freeze–thaw process, which is based on temperature and humidity variations, was employed in this study to assess the durability of applied materials. The outcomes of the adopted freeze–thaw system were compared with the results obtained from running a conventional freeze–thaw test. Mass change, water absorption, and microcracks development of treated concrete were investigated and compared with untreated concrete after completing 6 months of freeze–thaw cycles. Results confirmed the high affinity of the proposed materials to moisture at application time compared with silane. Additionally, it was demonstrated that moisture content has a critical impact on the bonding between applied materials and concrete, hence their efficacy in enhancing the durability of concrete.
Antarctic ecosystem responses following ice‐shelf collapse and iceberg calving: Science review and future research
Authors: Ingels Jeroen , Aronson Richard B. , Smith Craig R. , Baco Amy , Bik Holly M. , Blake James A. , Brandt Angelika , Cape Mattias , Demaster David , Dolan Emily , Domack Eugene , Fire Spencer , Geisz Heidi , Gigliotti Michael , Griffiths Huw , Halanych Kenneth M. , Havermans Charlotte , Huettmann Falk , Ishman Scott , Kranz Sven A. , Leventer Amy , Mahon Andrew R. , McClintock James , McCormick Michael L. , Mitchell B. Greg , Murray Alison E. , Peck Lloyd , Rogers Alex , Shoplock Barbara , Smith Kathryn E. , Steffel Brittan , Stukel Michael R. , Sweetman Andrew K. , Taylor Michelle , Thurber Andrew R. , Truffer Martin , van de Putte Anton , Vanreusel Ann , Zamora‐Duran Maria Angelica
Published: October 2020

The calving of A‐68, the 5,800‐km2, 1‐trillion‐ton iceberg shed from the Larsen C Ice Shelf in July 2017, is one of over 10 significant ice‐shelf loss events in the past few decades resulting from rapid warming around the Antarctic Peninsula. The rapid thinning, retreat, and collapse of ice shelves along the Antarctic Peninsula are harbingers of warming effects around the entire continent. Ice shelves cover more than 1.5 million km2 and fringe 75% of Antarctica's coastline, delineating the primary connections between the Antarctic continent, the continental ice, and the Southern Ocean. Changes in Antarctic ice shelves bring dramatic and large‐scale modifications to Southern Ocean ecosystems and continental ice movements, with global‐scale implications. The thinning and rate of future ice‐shelf demise is notoriously unpredictable, but models suggest increased shelf‐melt and calving will become more common. To date, little is known about sub‐ice‐shelf ecosystems, and our understanding of ecosystem change following collapse and calving is predominantly based on responsive science once collapses have occurred. In this review, we outline what is known about (a) ice‐shelf melt, volume loss, retreat, and calving, (b) ice‐shelf‐associated ecosystems through sub‐ice, sediment‐core, and pre‐collapse and post‐collapse studies, and (c) ecological responses in pelagic, sympagic, and benthic ecosystems. We then discuss major knowledge gaps and how science might address these gaps.

This article is categorized under:

Climate, Ecology, and Conservation > Modeling Species and Community Interactions
A new lower and upper bound estimation model using gradient descend training method for wind speed interval prediction
Authors: Liu Fangjie , Li Chaoshun , Xu Yanhe , Tang Geng , Xie Yuying
Published: October 2020

As a clean and renewable energy source, wind energy has achieved remarkable growth around the world. Wind power/speed interval prediction has become an indispensable area of focus regarding the efficient dispatch of wind energy. As an important interval prediction method, the traditional lower and upper bound estimation (LUBE) has been a prevalent approach and a fundamental branch of energy prediction. However, the traditional LUBE model suffers from a low training efficiency owing to a lack of the gradient descent (GD) training mechanism. In this study, an improved LUBE model was designed using a novel training scheme based on the GD method for better efficiency and greater prediction performance. Initially, the new objective functions, which are continuous and differential, meeting the requirements of the GD method, were designed to obtain the best prediction interval (PI) quality with a narrower PI width and greater coverage probability. Then, different loss function forms have been proposed and compared, with the new Huber loss function having been confirmed to be more effective than other traditional loss functions. Finally, the new LUBE model with an objective part and adapting to the GD training method was constructed. Both traditional and improved LUBE models with different loss functions were compared experimentally, and the results indicate that the improved LUBE model with a Huber loss function significantly reduces the training time and improves the quality of the PI.
Structural repair of wind turbine blades: Computational model for the evaluation of the effect of adhesive properties
Authors: Mischnaewski Lennart , Mishnaevsky Leon
Published: October 2020

Three‐dimensional (3‐D) finite element models of structural (scarf) repair of wind turbine blade, including the composite patch, adhesive, coating and parent composite structures is developed. Computational studies of the effect of the scarf angle, thickness of the adhesive layer and the availability of voids in the adhesive on the stress field in the repaired structure were carried out. It is observed that the soft adhesives lead to increased stresses in the parent laminate structures. The availability of voids in the adhesive leads to local stress concentration, and thus can reduce the postrepair reliability of the blades.
Generalized Schur–Nevanlinna functions and their realizations
Authors: Lilleberg Lassi
Published: October 2020

Pontryagin space operator valued generalized Schur functions and generalized Nevanlinna functions are investigated by using discrete-time systems, or operator colligations, and state space realizations. It is shown that generalized Schur functions have strong radial limit values almost everywhere on the unit circle. These limit values are contractive with respect to the indefinite inner product, which allows one to generalize the notion of an inner function to Pontryagin space operator valued setting. Transfer functions of self-adjoint systems such that their state spaces are Pontryagin spaces, are generalized Nevanlinna functions, and symmetric generalized Schur functions can be realized as transfer functions of self-adjoint systems with Kreĭn spaces as state spaces. A criterion when a symmetric generalized Schur function is also a generalized Nevanlinna function is given. The criterion involves the negative index of the weak similarity mapping between an optimal minimal realization and its dual. In the special case corresponding to the generalization of an inner function, a concrete model for the weak similarity mapping can be obtained by using the canonical realizations.
Macroporous epoxy-based monoliths for rapid quantification of Pseudomonas aeruginosa by adsorption elution method optimized for qPCR
Authors: Göpfert Lisa , Klüpfel Julia , Heinritz Charlotte , Elsner Martin , Seidel Michael
Published: October 2020

Pseudomonas aeruginosa contaminations in tap water systems have caused severe health problems in both hospital and household settings. To ensure fast and reliable detection, culture-independent methods are recommendable. However, the typically low cell number in water samples requires sample enrichment prior to analysis. Therefore, we developed and optimized an adsorption elution method using monolithic adsorption filtration and subsequent centrifugal ultrafiltration that can be combined with culture-independent detection methods. The principle of adsorption of Pseudomonas aeruginosa by hydrophobic and ionic interactions was studied in modified epoxy-based monoliths. Optimized conditions (5-L initial sample volume at pH 3 filtered for 30 min through hydrolyzed monoliths (MAF-OH) and eluted with beef extract glycine buffer at pH 9.5) achieved a recovery of 67.1 ± 1.2% and a concentration factor of 103. For the first time, we therefore present a culture-independent approach for rapid enrichment and subsequent molecular biological quantification of P. aeruginosa by qPCR from tap water samples by monolithic adsorption filtration. The total enrichment and quantification process takes 4 h. This work further stresses the versatility of the monolithic adsorption filtration and its possibilities as a concentration tool for culture-independent analytics of pathogenic bacteria in the environment.

Graphical abstract
The role of ulnar nerve subcutaneous anterior transposition during open reduction and internal fixation of distal humerus fractures: a retrospective cohort study
Authors: Ahmed Abdulaziz F. , Parambathkandi Ashik Mohsin , Kong Wai Jing Geraldine , Salameh Motasem , Mudawi Aiman , Abousamhadaneh Maamoun , Abuodeh Yousef , Ahmed Ghalib O.
Published: October 2020

Purpose

To compare the rates of ulnar nerve neuropathy following ulnar nerve subcutaneous anterior transposition versus no transposition during open reduction and internal fixation (ORIF) of distal humerus fractures.

Methods

This was a retrospective cohort study at an academic level I trauma centre. A total of 97 consecutive patients with distal humerus fractures underwent ORIF between 2011 and 2018. All included patients were treated with plates (isolated lateral plates excluded) and had no pre-operative ulnar neuropathy. Subcutaneous ulnar nerve anterior transposition was compared versus no transposition at the time of ORIF. The main outcome measure was the rate of ulnar nerve neuropathy. The secondary outcomes were the severity of the ulnar nerve neuropathy and the rate of ulnar nerve recovery.

Results

Twenty-eight patients underwent subcutaneous ulnar nerve anterior transposition during ORIF, whereas 69 patients had no transposition. Transposition was associated with significantly higher rates of ulnar nerve neuropathy (10/28 versus 10/69; P = 0.027). An adjusted logistic regression model demonstrated an odds ratio of 4.8 (1.3, 17.5; 95% CI) when transposition was performed. Ulnar nerve neuropathy was classified as McGowan grades 1 and 2 in all neuropathy cases in both groups (P = 0.66). Three out of ten cases recovered in the transposition group, and five out of ten cases recovered in the no transposition group over a mean follow-up of 11.2 months (P = 1.00).

Conclusion

We do not recommend performing routine subcutaneous ulnar nerve anterior transposition during ORIF of distal humerus fracture as it was associated with a significant 5-fold increase in ulnar nerve neuropathy.
Patient-derived organoids and orthotopic xenografts of primary and recurrent gliomas represent relevant patient avatars for precision oncology
Authors: Golebiewska Anna , Hau Ann-Christin , Oudin Anaïs , Stieber Daniel , Yabo Yahaya A. , Baus Virginie , Barthelemy Vanessa , Klein Eliane , Bougnaud Sébastien , Keunen Olivier , Wantz May , Michelucci Alessandro , Neirinckx Virginie , Muller Arnaud , Kaoma Tony , Nazarov Petr V. , Azuaje Francisco , De Falco Alfonso , Flies Ben , Richart Lorraine , Poovathingal Suresh , Arns Thais , Grzyb Kamil , Mock Andreas , Herold-Mende Christel , Steino Anne , Brown Dennis , May Patrick , Miletic Hrvoje , Malta Tathiane M. , Noushmehr Houtan , Kwon Yong-Jun , Jahn Winnie , Klink Barbara , Tanner Georgette , Stead Lucy F. , Mittelbronn Michel , Skupin Alexander , Hertel Frank , Bjerkvig Rolf , Niclou Simone P.
Published: October 2020

Patient-based cancer models are essential tools for studying tumor biology and for the assessment of drug responses in a translational context. We report the establishment a large cohort of unique organoids and patient-derived orthotopic xenografts (PDOX) of various glioma subtypes, including gliomas with mutations inIDH1, and paired longitudinal PDOX from primary and recurrent tumors of the same patient. We show that glioma PDOXs enable long-term propagation of patient tumors and represent clinically relevant patient avatars that retain histopathological, genetic, epigenetic, and transcriptomic features of parental tumors. We find no evidence of mouse-specific clonal evolution in glioma PDOXs. Our cohort captures individual molecular genotypes for precision medicine including mutations inIDH1,ATRX,TP53,MDM2/4, amplification ofEGFR,PDGFRA,MET,CDK4/6,MDM2/4, and deletion ofCDKN2A/B,PTCH, andPTEN. Matched longitudinal PDOX recapitulate the limited genetic evolution of gliomas observed in patients following treatment. At the histological level, we observe increased vascularization in the rat host as compared to mice. PDOX-derived standardized glioma organoids are amenable to high-throughput drug screens that can be validated in mice. We show clinically relevant responses to temozolomide (TMZ) and to targeted treatments, such as EGFR and CDK4/6 inhibitors in (epi)genetically defined subgroups, according toMGMTpromoter andEGFR/CDKstatus, respectively. Dianhydrogalactitol (VAL-083), a promising bifunctional alkylating agent in the current clinical trial, displayed high therapeutic efficacy, and was able to overcome TMZ resistance in glioblastoma. Our work underscores the clinical relevance of glioma organoids and PDOX models for translational research and personalized treatment studies and represents a unique publicly available resource for precision oncology.
Impact of frailty on the management of patients with gynecological cancer aged 80 years and older
Authors: Reiser Elisabeth , Pötsch Nina , Seebacher Veronika , Reinthaller Alexander , Wimazal Friedrich , Fleischmann Edith , Krainer Michael , Horvat Reinhart , Polterauer Stephan , Grimm Christoph
Published: October 2020

Purpose

To assess the impact of frailty on compliance of standard therapy, complication, rate and survival in patients with gynecological malignancy aged 80 years and older.

Methods

In total, 83 women with gynecological malignancy (vulva, endometrial, ovarian or cervical cancer) who underwent primary treatment between 2007 and 2017 were retrospectively analyzed. Frailty index was calculated and its association with compliance of standard treatment, peri- and postoperative mortality and morbidity, and survival was evaluated.

Results

Frailty was observed in 24.1% of cases. Both frail and non-frail patients were able to receive standard therapy in most cases − 75.0% and 85.7%, respectively (p = 0.27). Frail patients did not show an increased postoperative complication rate. Frail patients had shorter 3 years overall survival rates (28%) when compared to non-frail patients (55%) (p = 0.02). In multivariable analysis high frailty index (Hazard Ratio [HR] 12.15 [1.39–106.05], p = 0.02) and advanced tumor stage (HR 1.33 [1.00–1.76], p = 0.05) were associated with poor overall survival, but not age, histologic grading, performance status, and compliance of standard therapy.

Conclusion

Majority of patients was able to receive standard therapy, as suggested by the tumor board, irrespective of age and frailty. Nonetheless, frailty is a common finding in patients with gynecological malignancy aged 80 years and older. Frail patients show shorter progression-free, and overall survival within this cohort.
Cancer stem cell markers in adenocarcinoma of the salivary glands - reliable prognostic markers?
Authors: Spiegel Jennifer L. , Jakob Mark , Kruizenga Marie , Freytag Saskia , Bertlich Mattis , Canis Martin , Ihler Friedrich , Haubner Frank , Kitz Julia , Weiss Bernhard G.
Published: October 2020

Purpose

Adenocarcinoma of the salivary glands is of low incidence and a broad range of histopathological subtypes. Cancer stem cell markers (CSC) might serve as novel prognostic parameters. To date, only a few studies examined the expression of CSC in adenocarcinoma of the salivary glands with diverging results. To further investigate the reliability in terms of prognostic value, a histopathological analysis of CSCs on a cohort of patients with adenocarcinomas of the major salivary glands was performed.

Methods

Tumor samples of 40 consecutive patients with adenocarcinoma of the major salivary gland treated with curative intend at one tertiary center were stained with the CSCs ALDH1, BMI-1, CD44, Nanog, and SOX2. Expression of these markers was correlated with clinicopathological parameters and survival estimates.

Results

Correlation of high expression of ALDH1 with higher grading (p < 0.001) and high expression of CD44 with the localization of the neoplasm (p = 0.05), larger tumor size (p = 0.006), positive pN-category (p = 0.023), and advanced UICC stage (p = 0.002) was found. Furthermore, high expression of SOX2 correlated with a negative perineural invasion (p = 0.02). No significant correlation of any investigated marker with survival estimates was observed.

Conclusion

In conclusion, our study did not find a significant correlation of the investigated CSCs with survival estimates in adenocarcinoma of the major salivary glands. Recapitulating the results of our study in conjunction with data in the literature, the CSCs ALDH1, BMI-1, CD44, Nanog, and SOX2 do not seem to serve as reliable prognostic parameters in the treatment of adenocarcinoma of the salivary glands.
Case report of a cervical myelomalacia caused by a thoracolumbar intradural disc herniation leading to intracranial hypotension
Authors: Ueberschaer M. , Patzig M. , Mueller K. , Schwarting J. , Trabold R. , Tonn J.-C.
Published: October 2020

A 50-year-old patient was admitted with symptoms of intracranial hypotension. MRI revealed a cervical myelomalacia caused by engorged epidural veins leading to a stenosis of the spinal canal. This condition is rarely described in patients with hydrocephalus and ventricular shunts suffering from chronic overdrainage. However, the reason in this patient was a CSF leak caused by an intradural disc herniation at T12/L1. After surgery, symptoms resolved and the cervical myelomalacia and the swollen epidural veins disappeared on postoperative MRI.
In patients with engorged cervical epidural veins without a ventricular shunt, a CSF leak has to be considered.
Plant population and soil origin effects on rhizosphere nematode community composition of a range-expanding plant species and a native congener
Authors: Wilschut Rutger A. , Magnée Kim J. H. , Geisen S. , van der Putten W. H. , Kostenko O.
Published: October 2020

Climate change causes species range expansions to higher latitudes and altitudes. It is expected that, due to differences in dispersal abilities between plants and soil biota, range-expanding plant species will become associated with a partly new belowground community in their expanded range. Theory on biological invasions predicts that outside their native range, range-expanding plant species may be released from specialist natural enemies, leading to the evolution of enhanced defence against generalist enemies. Here we tested the hypothesis that expanded range populations of the range-expanding plant species Centaurea stoebe accumulate fewer root-feeding nematodes than populations from the original range. Moreover, we examined whether Centaurea stoebe accumulates fewer root-feeding nematodes in expanded range soil than in original range soil. We grew plants from three expanded range and three original range populations of C. stoebe in soil from the original and from the new range. We compared nematode communities of C. stoebe with those of C. jacea, a congeneric species native to both ranges. Our results show that expanded range populations of C. stoebe did not accumulate fewer root-feeding nematodes than populations from the original range, but that C. stoebe, unlike C. jacea, accumulated fewest root-feeding nematodes in expanded range soil. Moreover, when we examined other nematode feeding groups, we found intra-specific plant population effects on all these groups. We conclude that range-expanding plant populations from the expanded range were not better defended against root-feeding nematodes than populations from the original range, but that C. stoebe might experience partial belowground enemy release.
Approximation Guarantee of OSP Mechanisms: The Case of Machine Scheduling and Facility Location
Authors: Ferraioli Diodato , Ventre Carmine
Published: October 2020

Obvious strategyproofness (OSP) is an appealing concept as it allows to maintain incentive compatibility even in the presence of agents that are not fully rational, i.e., those who struggle with contingent reasoning (Li in Am Econ Rev 107(11):3257–3287, 2017). However, it has been shown to impose some limitations, e.g., no OSP mechanism can return a stable matching (Ashlagi and Gonczarowski in J Econ Theory 177:405–425, 2018). We here deepen the study of the limitations of OSP mechanisms by looking at their approximation guarantees for basic optimization problems paradigmatic of the area, i.e., machine scheduling and facility location. We prove a number of bounds on the approximation guarantee of OSP mechanisms, which show that OSP can come at a significant cost. However, rather surprisingly, we prove that OSP mechanisms can return optimal solutions when they use monitoring—a novel mechanism design paradigm that introduces a mild level of scrutiny on agents’ declarations (Kovács et al. in WINE 9470:398–412, 2015).
Use of fractal models to define the scaling behavior of the aquifers’ parameters at the mesoscale
Authors: Fallico C. , De Bartolo S. , Brunetti G. F. A. , Severino G.
Published: October 2020

We present an experimental study aiming at the identification of the hydraulic conductivity in an aquifer which was packed according to four different configurations. The conductivity was estimated by means of slug tests, whereas the other parameters were determined by the grain size analysis. Prior to the fractal we considered the dependence of the conductivity upon the porosity through a power (scaling) law which was found in a very good agreement within the range from the laboratory to the meso-scale. The dependence of the conductivity through the porosity was investigated by identifying the proper fractal model. Results obtained provide valuable indications about the behavior, among the others, of the tortuosity, a parameter playing a crucial role in the dispersion phenomena taking place in the aquifers.