bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dual Roles of tert‐Butyl Nitrite in the Transition Metal‐ and External Oxidant‐Free Trifluoromethyloximation of Alkenes
Authors: Wu Ya , Zhang Yanli , Yang Zhen , Jiao Jingchao , Zheng Xiaoke , Feng Weisheng , Zhang Mengsha , Cheng Hao , Tang Lin 
Published: July 2019

AbstractBy employing tert‐butyl nitrite as both nitrogen source and oxidant, the trifluoromethyloximation of alkenes proceeds smoothly in a free‐radical process. The developed difunctionalization reaction enables practical and efficient synthesis of a wide range of α‐CF3 ketoximes in moderate yields with excellent regioselectivity. This method features the use of readily available and stable alkenes as substrates and inexpensive CF3SO2Na as a CF3 reagent, no involvement of transition metals or external oxidant, and room‐temperature conditions. Moreover, a scale‐up of the reaction, further transformation of the products into various valuable CF3‐containing compounds, and removal of the trifluoromethyl group are readily achieved.
A secure multifactor remote user authentication scheme for Internet of Multimedia Things environment
Authors: Dhillon Parwinder Kaur , Kalra Sheetal 
Published: July 2019

SummaryTo attain ubiquitous connectivity of everything, Internet of Things (IoT) systems must include “multimedia things.” Internet of Multimedia Things (IoMT) is a heterogeneous network of smart multimedia things connected together and with other physical devices to the Internet so as to achieve globally available multimedia services and applications. Due to the ever increasing amount of multimedia data in IoT environments, securing these systems becomes crucial. This is because these systems are easily susceptible to attacks when information or any service is accessed by the users. In this paper, we propose a secure three‐factor remote user authentication scheme for IoMT systems using ECC. The formal security proof performed using ROR model and BAN logic confirms that an attacker will not be able to extract sensitive user information. Through informal security analysis, we justify the resistance of the scheme against several security attacks. The performance comparison shows that the scheme is efficient in terms of computational cost, security features, and attack resistance. Furthermore, simulation of the scheme using AVISPA and Proverif proves that the scheme is secure against all active and passive attacks.
Landscape‐level validation of allometric relationships for carbon stock estimation reveals bias driven by soil type
Authors: Beirne C. , Miao Z. , Nuñez C. L. , Medjibe V. P. , Saatchi S. , White L. J. T. , Poulsen J. R. 
Published: July 2019

AbstractMitigation of climate change depends on accurate estimation and mapping of terrestrial carbon stocks, particularly in carbon dense tropical forests. Allometric equations can be used to robustly estimate biomass of tropical trees, but often require tree height, which is frequently unknown. Researchers and practitioners must, therefore, decide whether to directly measure a subset of tree heights to develop diameter : height (D:H) equations or rely on previously published generic equations. To date, studies comparing the two approaches have been spatially restricted and/or not randomly allocated across the landscape of interest, making the implications of deciding whether or not to measure tree heights difficult to determine. To address this issue, we use inventory data from a systematic‐random forest inventory across Gabon (102 forest sites; 42,627 trees, including 7,036 height‐measured trees). Using plot‐specific models ofD:Has a benchmark, we compare the performance of a suite of locally fitted and commonly used generic models (parameterized national, georegional, and pantropical equations) across a variety of scales, and assess which abiotic, anthropogenic, and topographical covariates contribute the most to bias in height estimation. We reveal marked spatial structure in the magnitude and direction of bias in tree height estimation using all generic models, due at least in part to soil type, which compounded to substantial error in site‐levelAGBestimates (of up to 38% or 150 Mg/ha). However, two generic pantropical models (Chave 2014; Feldpausch 2012) converged to within 2.5% of meanAGBat the landscape scale. Our results suggest that some (not all) pantropical equations can extrapolateAGBacross large spatial scales with minimal bias in estimated meanAGB. However, extreme caution must be taken when interpreting theAGBestimates from generic models at the site‐level as they fail to capture substantial spatial variation inD:Hrelationships, which could lead to dramatic under‐ or over‐estimation of site‐level carbon stocks. Validated allometric models derived at site‐ or soil‐type‐levels may be the best way to reduce such biases arising from landscape‐level heterogeneity inD:Hmodel fit in the Afrotropics.
The posited effect of positive affect in anorexia nervosa: Advocating for a forgotten piece of a puzzling disease
Authors: Coniglio Kathryn A. , Christensen Kara A. , Haynos Ann F. , Rienecke Renee D. , Selby Edward A. 
Published: July 2019

AbstractAnorexia nervosa (AN) is a complex and life‐threatening eating disorder. Current models of AN onset and maintenance have largely focused on the role of negative affect, while fewer models have described the role of positive affect (PA). Given that these theoretical models have informed current treatment approaches, and that treatment remains minimally effective for adults with AN, we advocate that targeting PA is one avenue for advancing maintenance models and by extension, treatment. We specifically propose that AN may arise and be chronically and pervasively maintained as a function of dysregulated PA in response to weight loss and weight loss behaviors (e.g., restriction, excessive exercise), to a degree that is not accounted for in existing models of AN. We present evidence from multiple domains, including biological, behavioral, and self‐report, supporting the hypothesis that PA dysregulation in AN contributes to the maintenance of the disorder. We conclude with several specific avenues for treatment development research as well as a call for future work elucidating the biological correlates of PA.
Moderate grazing promotes the root biomass in Kobresia meadow on the northern Qinghai–Tibet Plateau
Authors: Dai Licong , Guo Xiaowei , Ke Xun , Zhang Fawei , Li Yikang , Peng Cuoji , Shu Kai , Li Qian , Lin Li , Cao Guangmin , Du Yangong 
Published: July 2019

AbstractGrazing is an important modulator of both plant productivity and biodiversity in grassland community, yet how to determine a suitable grazing intensity in alpine grassland is still controversy. Here, we explore the effects of different grazing intensities on plant biomass and species composition, both at community level and functional group level, and examines the productivity–species richness relationship under four grazing patterns: no grazing (CK), light grazing (LG), moderate grazing, (MG) and heavy grazing (HG), attempt to determine a suitable grazing intensity in alpine grassland. The results were as follows. The total aboveground biomass (AGB) reduced with increasing grazing intensity, and the response of plant functional groups was different. AGB of both sedges and legumes increased from MG to HG, while the AGB of forbs reduced sharply and the grass AGB remained steady. There was a significant positive relationship between productivity and species richness both at community level and functional group level. In contrast, the belowground biomass (BGB) showed a unimodal relationship from CK to HG, peaking in MG (8,297.72 ± 621.29 g/m2). Interestingly, the grassland community tends to allocate more root biomass to the upper soil layer under increasing grazing intensities. Our results suggesting that moderate levels of disturbance may be the optimal grassland management strategy for alpine meadow in terms of root production.
Calculation of narrower confidence intervals for tree mortality rates when we know nothing but the location of the death/survival events
Authors: Arellano Gabriel 
Published: July 2019

Abstract

Many ecological applications, like the study of mortality rates, require the estimation of proportions and confidence intervals for them. The traditional way of doing this applies the binomial distribution, which describes the outcome of a series of Bernoulli trials. This distribution assumes that observations are independent and the probability of success is the same for all the individual observations. Both assumptions are obviously false in many cases.

I show how to apply bootstrap and the Poisson binomial distribution (a generalization of the binomial distribution) to the estimation of proportions. Any information at the individual level would result in better (narrower) confidence intervals around the estimation of proportions. As a case study, I applied this method to the calculation of mortality rates in a forest plot of tropical trees in Lambir Hills National Park, Malaysia.

I calculated central estimates and 95% confidence intervals for species‐level mortality rates for 1,007 tree species. I used a very simple model of spatial dependence in survival to estimate individual‐level risk of mortality. The results obtained by accounting for heterogeneity in individual‐level risk of mortality were comparable to those obtained with the binomial distribution in terms of central estimates, but the precision increased in virtually all cases, with an average reduction in the width of the confidence interval of ~20%.

Spatial information allows the estimation of individual‐level probabilities of survival, and this increases the precision in the estimates of mortality rates. The general method described here, with modifications, could be applied to reduce uncertainty in the estimation of proportions related to any spatially structured phenomenon with two possible outcomes. More sophisticated approaches can yield better estimates of individual‐level mortality and thus narrower confidence intervals.
Body mass index and outcomes of cardiac resynchronization with implantable cardioverter‐defibrillator therapy in older patients with heart failure
Authors: Echouffo‐Tcheugui Justin B. , Masoudi Frederick A. , Bao Haikun , Curtis Jeptha P. , Heidenreich Paul A. , Fonarow Gregg C. 
Published: July 2019

AimsTo assess the association of body mass index (BMI) with heart failure (HF) outcomes after cardiac resynchronization therapy with defibrillator (CRT‐D) implantation.Methods and resultsMedicare beneficiaries with HF aged ≥ 65 years (n = 18 922) undergoing first‐time CRT‐D from the National Cardiovascular Data Registry (NCDR) Implantable Cardioverter‐Defibrillator Registry between 2010 and 2013, were followed for 3 years post‐implantation. Survival curves and covariate adjusted hazard ratio (aHR) or odds ratio were used to assess the risks for death, readmission, and device‐related complications by BMI status. Of 18 922 HF patients receiving CRT‐D, 5265 (27.8%) were normal weight, 6896 (37%) were overweight, 6318 (33.4%) were obese, and 353 (1.8%) were underweight. Compared to those of normal weight (BMI 18.5–24.9 kg/m2), underweight patients had a higher 3‐year post‐device implantation risk of death [aHR: 1.34 (95% confidence interval 1.09–1.65); P < 0.001] and of readmission [sub‐aHR: 1.25 (1.09–1.42); P < 0.001]. The corresponding 3‐year aHRs for death were 0.83 (0.77–0.89) for overweight, 0.74 (0.67–0.82) for obesity class I (BMI 30–34.9 kg/m2), 0.78 (0.68–0.90) for obesity class II (BMI 35–39.9 kg/m2), and 0.75 (0.60–0.93) for obesity class III (BMI ≥ 40 kg/m2, P for all categories < 0.001). Individuals with class III obesity had a higher risk of readmission [sub‐aHR: 1.17 (1.06–1.30)]. There were no differences in rates of device‐related complications within 90 days across BMI categories.ConclusionMost elderly patients with HF receiving CRT‐D were overweight or obese. While being underweight was associated with greater risks of death and hospitalization, overweight and obese patients were at lower risk of death after CRT‐D.
Technical and clinical performance of the thermo‐test device “Q‐Sense” to assess small fibre function: A head‐to‐head comparison with the “Thermal Sensory Analyzer” TSA in diabetic patients and healthy volunteers
Authors: Pfau Doreen B. , Greffrath Wolfgang , Schilder Andreas , Magerl Walter , Ohler Carolin , Westermann Andrea , Maier Christoph , Doppler Kathrin , Sommer Claudia , Orth Michael , Hammes Hans‐Peter , Kurz Jochen , Götz Marcus , Treede Rolf‐Detlef , Schuh‐Hofer Sigrid 
Published: July 2019

AbstractBackgroundThermo‐test devices are rarely used outside specialized pain centres because of high acquisition costs. Recently, a new, portable device (“Q‐Sense”) was introduced, which is less expensive but has reduced cooling capacity (20°C). We assessed the reliability/validity of the “Q‐Sense” by comparing it with the Thermal Sensory Analyzer (TSA).MethodsUsing a phantom‐skin model, the physical characteristics of both devices were compared. The clinical performance was assessed in a multicentre study by performing Quantitative Sensory Testing (QST) in 121 healthy volunteers and 83 diabetic patients (Eudra‐Med‐No. CIV‐12‐05‐006501).ResultsBoth device types showed ~40% slower temperature ramps for heating/cooling than nominal data. Cold/warm detection thresholds (CDT, WDT) and heat pain thresholds (HPT) of healthy subjects did not differ between device types. Cold pain thresholds (CPT) were biased for Q‐Sense by a floor effect (p < .001). According to intraclass correlation coefficients (ICC), agreement between TSA and Q‐Sense was good/excellent for CDT (ICC = 0.894) and WDT (ICC = 0.898), moderate for HPT (ICC = 0.525) and poor for CPT (ICC = 0.305). In diabetic patients, the sensitivity of Q‐Sense to detect cold hypoesthesia was reduced in males >60 years. Moderate correlations between thermal detection thresholds and morphological data from skin biopsies (n = 51) were similar for both devices.ConclusionsPhysical characteristics of both thermo‐test devices are similarly limited by the poor temperature conduction of the skin. The Q‐Sense is useful for thermal detection thresholds but of limited use for pain thresholds. For full clinical use, the lower cut‐off temperature should be set to ≤18°C.SignificanceHigh purchase costs prevent a widespread use of thermo‐test devices for diagnosing small fibre neuropathy. The air‐cooled “Q‐Sense” could be a lower cost alternative, but its technical/clinical performance needs to be assessed because of its restricted cut‐off for cooling (20°C). This study provides critical information on the physical characteristics and the clinical validity/reliability of the Q‐Sense compared to the “Thermal Sensory Analyzer” (TSA). We recommend lowering the cut‐off value of the Q‐Sense to ≤18°C for its full clinical use.
Post‐fire soil erosion mitigation at the scale of swales using forest logging residues at a reduced application rate
Authors: Prats Sergio A. , González‐Pelayo Óscar , Silva Flavio C. , Bokhorst Koen J. , Baartman Jantiene E.M. , Keizer Jan J. 
Published: July 2019

AbstractMulching with forest residues has proved to be highly effective in reducing post‐fire soil losses at the plot scale. However, its effectiveness has not been quantified at the application rates that are typically used in operational post‐fire land management (2–3 Mg ha‐1 using straw), as well as at scales larger than 100 m2. The present study compared post‐fire erosion rates for six convergent hillslopes or swales of 500 to 800 m2, three of which were left untreated while the other three were mulched immediately after the fire with shredded eucalypt bark at a rate of 2.4 Mg ha‐1. Erosion rates were monitored at irregular intervals during the first three post‐fire years, whilst ground cover was assessed yearly. Selected topsoil properties (0–2 cm) such as organic matter content and aggregate stability were determined at a single occasion – two years after the wildfire, for three micro‐environments separately: bare soil, and under mulch/litter and vegetation. Soil losses on the untreated swales decreased with post‐fire year from 2.2 to 0.4 and 0.11 Mg ha‐1 yr‐1 (respectively for the first, second and third post‐fire years), while the mulched swales produced 84%, 77% and 38% less soil losses than the untreated swales.Soil losses also depended on slope aspect, with the north‐facing swales producing less erosion than the west‐facing ones. This could be linked to their significant differences in bare soil, vegetation and stone cover, or a combination thereof. The type of micro‐environment also played a significant role in topsoil properties (stone content, bulk density, resistance to penetration/shear stress, porosity and organic matter content). The present results add to the increasing evidence that forest residues should be duly considered for operational post‐fire land management. Forest residues were highly effective in reducing erosion from swales at application rates as low as the typical 2 Mg ha‐1 of post‐fire straw mulch. © 2019 John Wiley & Sons, Ltd. © 2019 John Wiley & Sons, Ltd.
An intelligent SDN‐enabled CCN routing mechanism with community division
Authors: Zhang Songzhu , Wang Xingwei , Qian Xiaohu , Huang Min 
Published: July 2019

AbstractIn recent years, Content‐Centric Networking (CCN) has been considered as a novel promising paradigm for the future Internet, shifting from provider‐driven end‐to‐end communication mode to interest‐driven content retrieval communication one, which greatly depends on routing technology. In spite of this, CCN routing always faces two significant issues, ie, scalability and large‐scale deployment, which restrict the increasing development of CCN but can be addressed by introducing the ideas of Software‐Defined Networking (SDN) and community (domain) division. However, the current routing proposals on the integrating with SDN, community division or their combination, still have some limitations to be improved. Therefore, in this paper, we propose a novel and intelligent CCN Routing mechanism based on SDN and Community Division (CRSCD). At first, a community division scheme based on eigenvetor centrality and label propagation is proposed to help content retrieval. Then, for each divided community, we deploy an SDN controller which consists of two tables, ie, content index and community topology to help manage the global network view. Finally, a comprehensive routing mechanism including intracommunity routing based on Ant Colony Optimization (ACO) and intercommunity routing based on interaction frequency is devised. The proposed CRSCD is implemented over Cogent topology, and the experimental results demonstrate that the introduction of SDN and community division can accelerate content retrieval greatly and has better performance than the previous work.
Signal reconstruction in diffusion‐based molecular communication
Authors: Atakan Baris , Gulec Fatih 
Published: July 2019

AbstractMolecular communication (MC) is an important nanoscale communication paradigm, which is employed for the interconnection of the nanomachines (NMs) to form nanonetworks. A transmitter NM (TN) sends the information symbols by emitting molecules into the transmission medium and a receiver NM (RN) receives the information symbols by sensing the molecule concentration. In this paper, a model of how an RN measures and reconstructs the molecular signal is proposed. The signal around the RN is assumed to be a Gaussian random process instead of the less realistic deterministic approach. After the reconstructed signal is derived as a doubly stochastic poisson process, the distortion between the signal around the RN and the reconstructed signal is derived as a new performance parameter in MC systems. The derived distortion, which is a function of system parameters such as RN radius, sampling period, and the diffusion coefficient of the channel, is shown to be valid by employing random walk simulations. Then, it is shown that the original signal can be satisfactorily reconstructed with a sufficiently low level of distortion. Finally, optimum RN design parameters, namely, RN radius, sampling period, and sampling frequency, are derived by minimizing the signal distortion. The simulation results reveal that there is a trade‐off among the RN design parameters which can be jointly set for a desired signal distortion.
Logiken der Freiheit
Authors: Möllers Christoph 
Published: July 2019

AbstractDas Grundgesetz garantiert seit 70 Jahren beide als Grundrechte – doch verglichen mit der Freiheit der Kunst ist die Freiheit der Wissenschaft komplizierter gebaut und lässt sich eventuell auch schwerer verteidigen. Das liegt nicht zuletzt an der konstitutiven Rolle des Staates.
Lernen, erinnern und vergessen
Authors: Unterstell Rembert 
Published: July 2019

AbstractDer Neurobiologe Martin Korte untersucht die zellulären Grundlagen von Gedächtnisvorgängen – und verbindet ambitionierte Forschung mit vielseitiger Wissenschaftsvermittlung. Eine Begegnung an der TU Braunschweig
Nähe mit Licht und Schatten
Authors: Kappeler Peter 
Published: July 2019

AbstractLemuren, Makaken und Schimpansen: Sie alle leben in komplexen Gesellschaften, die auch die Gesundheit der Gruppenmitglieder beeinflussen. Enge Bindungen können sozialen Stress abmildern, erhöhen aber auch das Übertragungsrisiko für Parasiten oder Geschlechtskrankheiten.
Altered transient brain dynamics in multiple sclerosis: Treatment or pathology?
Authors: Van Schependom Jeroen , Vidaurre Diego , Costers Lars , Sjøgård Martin , D'hooghe Marie B. , D'haeseleer Miguel , Wens Vincent , De Tiège Xavier , Goldman Serge , Woolrich Mark , Nagels Guy 
Published: July 2019

AbstractMultiple sclerosis (MS) is a demyelinating, neuroinflammatory, and ‐degenerative disease that affects the brain's neurophysiological functioning through brain atrophy, a reduced conduction velocity and decreased connectivity. Currently, little is known on how MS affects the fast temporal dynamics of activation and deactivation of the different large‐scale, ongoing brain networks. In this study, we investigated whether these temporal dynamics are affected in MS patients and whether these changes are induced by the pathology or by the use of benzodiazepines (BZDs), an important symptomatic treatment that aims at reducing insomnia, spasticity and anxiety and reinforces the inhibitory effect of GABA. To this aim, we employed a novel method capable of detecting these fast dynamics in 90 MS patients and 46 healthy controls. We demonstrated a less dynamic frontal default mode network in male MS patients and a reduced activation of the same network in female MS patients, regardless of BZD usage. Additionally, BZDs strongly altered the brain's dynamics by increasing the time spent in the deactivating sensorimotor network and the activating occipital network. Furthermore, BZDs induced a decreased power in the theta band and an increased power in the beta band. The latter was strongly expressed in those states without activation of the sensorimotor network. In summary, we demonstrate gender‐dependent changes to the brain dynamics in the frontal DMN and strong effects from BZDs. This study is the first to characterise the effect of multiple sclerosis and BZDs in vivo in a spatially, temporally and spectrally defined way.