bluuebunny/crossref_metadata_2025_split huggingface dataset:
Drought sensitivity of Empetrum nigrum shrub growth at the species’ southern lowland distribution range margin
Authors: Hein Nils , Merkelbach Julia , Zech Katharina , Weijers Stef 
Published: December 2020

AbstractThe ongoing warming of the Earth’s atmosphere is projected to cause a northward shift of species’ distributions, as they track their climatic optimum. In the rapidly warming Arctic, this has already led to an increase of shrubs in tundra ecosystems. While this northern expansion of woody biomass has been studied relatively extensively over the last decade, little research has been devoted to shrub growth responses at the southern margins of Northern Hemisphere shrubs. Here, we studied shoot length growth, its responses to climate over the period 2010–2017, and differences in leaf C and N content of the evergreen dwarf shrubEmpetrum nigrum, as well as the vegetation composition and soil parameters at four sites located along a gradient of increasing dune age on the island Spiekeroog, northern Germany. The sites are located in the tri-national UNESCO world heritage site, the Wadden Sea.E. nigrumhas a predominantly circum-arctic-boreal distribution and its southern distribution margin in European lowlands runs through northern Germany, where it is retreating northwards. We found a negative response to autumn (surface) temperatures and previous summer surface temperatures and/or a positive response to summer precipitation ofE. nigrumgrowth, except at the oldest dune with the strongestE. nigrumdominance. Growth rates and plant species diversity declined with dune age. Our results suggest thatE. nigrumgrowth is drought sensitive at its European southern range margin. We hypothesize that this sensitivity may form the basis for its northward retreat, which is supported by recent observations ofE. nigrumdieback in Germany after the extreme drought in 2018 and model projections.
Aerobic fitness is a potential crucial factor in protecting paralympic athletes with locomotor impairments from atherosclerotic cardiovascular risk
Authors: Bernardi Marco , Romano Silvio , Squeo Maria Rosaria , Guerra Emanuele , Adami Paolo Emilio , Alviti Federica , Mattei Antonella , Corsi Loretta , Lanzano Riccardo , Curatulo Pietro Giacomo , Mandolesi Dimitri , Parisi Fabiana , Di Giacinto Barbara , Dante Donatella , Marini Claudio , Mashkovskiy Evgeny , Ordonez Francisco Javier , Spataro Antonio 
Published: December 2020

Abstract
Purpose
To test the hypothesis that aerobic fitness is inversely related to the risk of atherosclerotic cardiovascular disease (ACVD) in athletes with locomotor impairments deriving from health conditions, such as spinal cord injury (SCI), lower limb amputation, cerebral palsy, poliomyelitis, and other health conditions different from the previous ones.

Methods
A total of 68 male athletes who competed in either summer or winter Paralympic games were divided in two health conditions groups (35 with SCI, mean age 37.2 ± 8.0 years, and 33 with different health conditions, mean age 37.8 ± 9.9 years) and in four sport type groups (skill, power, intermittent—mixed metabolism—and endurance). They were evaluated through anthropometric and blood pressure measurements, laboratory blood tests, and graded cardiopulmonary maximal arm cranking exercise test, with oxygen uptake peak (VO2peak) measurement. Cardiovascular risk profile was assessed in each athlete.

Results
The prevalence of ACVD-risk factors in the overall population was 20.6% for hypertension; 47% and 55.9% for high values of total and LDL cholesterol, respectively; 22.1% for reduce glucose tolerance; and 8.8% for obesity. No difference was found between athletes with and without SCI, while the prevalence of obesity was significantly higher in those practicing skill sports (22.7%, p = 0.035), which was the sport type group with Paralympic athletes with the lowest VO2peak (22.5 ± 5.70 ml kg−1 min−1). VO2peak was lower in athletes with SCI than those with different health conditions (28.6 ± 10.0 vs 33.6 ± 8.9 ml kg−1 min−1p = 0.03), and in those with 3–4 risk factors (19.09 ± 5.34 ml kg−1 min−1) than those with 2 risk factors (27.1 ± 5.50 ml kg−1 min−1), 1 risk factor (31.6 ± 8.55 ml kg−1 min−1), or none (36.4 ± 8.76 ml kg−1 min−1) (p < 0.001).

Conclusions
The present study suggests that having higher VO2peak seems to offer greater protection against ACVD in individuals with a locomotor impairment. Prescribing physical exercise at an intensity similar to that of endurance and intermittent sports should become a fundamental tool to promote health among people with a locomotor impairment.
A large-scale comprehensive evaluation of single-slice ring oscillator and PicoPUF bit cells on 28-nm Xilinx FPGAs
Authors: Gu Chongyan , Chang Chip-Hong , Liu Weiqiang , Hanley Neil , Miskelly Jack , O’Neill Máire 
Published: December 2020

AbstractLightweight implementation of security primitives, e.g., physical unclonable functions (PUFs) and true random number generator, in field programmable gate array (FPGA) is crucial replacement of the conventional decryption key stored in battery-backed random access memory or E-Fuses for the protection of field reconfigurable assets. A slice is the smallest reconfigurable logic block in an Xilinx FPGA. The entropy exploitable from each slice of an FPGA is an important factor for the design of security primitives. Previous research has shown that the locations of slices can impact the quality of delay-based PUF designs implemented on FPGAs. To investigate the effect of the placement of each single-bit PUF cell free from the routing resource constraint between slices, single-bit ring oscillator (RO) and identity-based PUF design (Pi-coPUF) cells that can each be fully fitted into a single slice are evaluated. To accurately evaluate their statistical performance, data from a large number of devices are required. To this end, 217 Xilinx Artix-7 FPGAs has been employed to provide a large-scale comprehensive analysis for the two designs. This is the first time single-slice disorder-based security entities have been investigated and compared on 28-nm Xilinx FPGA. Uniqueness, uniformity, correlation, reliability, bit-aliasing and min-entropy of each type of cell are evaluated for four different types of cell placement. Our experimental results corroborate that the location of both cell types in the FPGA affects their performances. For both cell types, the lower the correlation between devices, the higher the min-entropy and uniqueness. Overall, the min-entropy, correlation and uniqueness of PicoPUF are slightly higher than those of RO. Otherwise, the uniformity, bit-aliasing and reliability of the PicoPUF are slightly lower than those of the RO. Comparing the resource usage and metrics of the PicoPUF, ring oscillator PUF and some existing memory-based PUF implementations, PicoPUF stands out as a lightweight FPGA-based weak PUF design. The raw data for the PicoPUF design are made publicly available to enable the research community to use them for benchmarking and/or validation.
SCA secure and updatable crypto engines for FPGA SoC bitstream decryption: extended version
Authors: Unterstein Florian , Jacob Nisha , Hanley Neil , Gu Chongyan , Heyszl Johann 
Published: December 2020

AbstractFPGA system on chips (SoCs) are ideal computing platforms for edge devices in applications which require high performance through hardware acceleration and updatability due to long operation in the field. A secure update of hardware functionality can in general be achieved by using built-in cryptographic engines and provided secret key storage. However, reported examples have shown that such cryptographic engines may become insecure against side-channel attacks at any later point in time. This leaves already deployed systems vulnerable without any clear mitigation options. To solve this, we propose a comprehensive concept that uses an alternative and side-channel protected cryptographic engine within the FPGA logic instead of the built-in one for the crucial task of bitstream decryption. Remarkably this concept even allows to update the cryptographic engine itself. As proof of concept, we describe an application to the Xilinx Zynq-7020 FPGA SoC in detail. We provide two options for a leakage resilient decryption engine which are based on the same primitive, a leakage resilient pseudorandom function (LR-PRF). Depending on a side-channel evaluation of this primitive on the target platform, either a version with additional side-channel countermeasures or a more efficient variant is deployed. The lack of accessible secret key storage poses a significant challenge and requires the use of a physical unclonable function (PUF) to generate a device intrinsic secret within the FPGA logic. At the same time this means that manufacturer-provided secret key storage or cryptography is no longer required; only a public key for signature verification of the first stage bootloader and initial static bitstream. We provide empirical results proving the side-channel security of the protected cryptographic engine as well as an evaluation of the PUF quality. The full design and source code is made available to encourage further research in this direction.
The Wolfiporia Cocos Genome and Transcriptome Shed Light on the Formation of Its Edible and Medicinal Sclerotium
Authors: Luo Hongmei , Qian Jun , Xu Zhichao , Liu Wanjing , Xu Lei , Li Ying , Xu Jiang , Zhang Jianhong , Xu Xiaolan , Liu Chang , He Liu , Li Jianqin , Sun Chao , Martin Francis , Song Jingyuan , Chen Shilin 
Published: December 2020

Abstract
Wolfiporia cocos (F. A. Wolf) has been praised as a food delicacy and medicine for centuries in China. Here, we present the genome and transcriptome of the Chinese strain CGMCC5.78 of W. cocos. High-confidence functional prediction was made for 9277 genes among the 10,908 total predicted gene models in the W. cocos genome. Up to 2838 differentially expressed genes (DEGs) were identified to be related to sclerotial development by comparing the transcriptomes of mycelial and sclerotial tissues. These DEGs are involved in mating processes, differentiation of fruiting body tissues, and metabolic pathways. A number of genes encoding enzymes and regulatory factors related to polysaccharide and triterpenoid production were strikingly regulated. A potential triterpenoid gene cluster including the signature lanosterol synthase (LSS) gene and its modified components were annotated. In addition, five nonribosomal peptide synthase (NRPS)-like gene clusters, eight polyketide synthase (PKS) gene clusters, and 15 terpene gene clusters were discovered in the genome. The differential expression of the velevt family proteins, transcription factors, carbohydrate-active enzymes, and signaling components indicated their essential roles in the regulation of fungal development and secondary metabolism in W. cocos. These genomic and transcriptomic resources will be valuable for further investigations of the molecular mechanisms controlling sclerotial formation and for its improved medicinal applications.
Monthly Patterns of Ammonia Over the Contiguous United States at 2‐km Resolution
Authors: Wang Rui , Guo Xuehui , Pan Da , Kelly James T. , Bash Jesse O. , Sun Kang , Paulot Fabien , Clarisse Lieven , Van Damme Martin , Whitburn Simon , Coheur Pierre‐François , Clerbaux Cathy , Zondlo Mark A. 
Published: December 2020

AbstractMonthly, high‐resolution (∼2 km) ammonia (NH3) column maps from the Infrared Atmospheric Sounding Interferometer (IASI) were developed across the contiguous United States and adjacent areas. Ammonia hotspots (95th percentile of the column distribution) were highly localized with a characteristic length scale of 12 km and median area of 152 km2. Five seasonality clusters were identified with k‐means++ clustering. The Midwest and eastern United States had a broad, spring maximum of NH3 (67% of hotspots in this cluster). The western United States, in contrast, showed a narrower midsummer peak (32% of hotspots). IASI spatiotemporal clustering was consistent with those from the Ammonia Monitoring Network. CMAQ and GFDL‐AM3 modeled NH3 columns have some success replicating the seasonal patterns but did not capture the regional differences. The high spatial‐resolution monthly NH3 maps serve as a constraint for model simulations and as a guide for the placement of future, ground‐based network sites.
Helium and Argon Partitioning Between Liquid Iron and Silicate Melt at High Pressure
Authors: Xiong Zhihua , Tsuchiya Taku , Van Orman James A. 
Published: December 2020

AbstractWhether Earth’s core is a significant repository of noble gases is an open question because their partitioning between liquid metal and silicate melt during core formation is poorly known. Here we calculated the He and Ar partition coefficients (D) between liquid Fe and MgSiO3 melt from 20 to 135 GPa at 5,000 K using ab initio molecular dynamics combined with thermodynamic integration. Our simulations show that DHe does not change significantly with pressure, while DAr increases strongly with increasing pressure. Furthermore, we found that the metal/silicate partitioning behaviors of He and Ar are controlled by their atomic size and the charge density properties of the host compositions. These results indicate that Earth’s core is a plausible reservoir for 3He and could possibly account for the high 3He/4He ratios in the OIBs that associated with deep‐rooted plumes, but the core is unlikely to be a significant source for 36Ar.
Free‐Surface‐Induced Supershear Transition in 3‐D Simulations of Spontaneous Dynamic Rupture on Oblique Faults
Authors: Tang Rongjiang , Yuan Jie , Gan Lu 
Published: December 2020

AbstractSeveral observations and simulations suggested that the supershear rupture induced by free surface invariably occurs in strike‐slip faults rather than in dip‐slip faults. To explore the mechanism of supershear transition induced by free surface on oblique faults, we simulate spontaneous dynamic rupture propagation governed by slip‐weakening friction on nonvertical planar faults. We find that oblique thrust faults are more likely to produce free‐surface‐induced supershear transition than oblique normal faults and significant asymmetry arises between the two opposite directions along fault strike. The supershear rupture may only occur within shallow depth or over the entire seismogenic depth, depending on geometric relations between the slip and rupture propagation vectors. Our results help explain the lack of universal observation of supershear earthquakes. Besides, the asymmetric ground shaking on the oblique faults allows us to predict the possible spatial distribution of the high seismic risk.
Probabilistic Geomagnetic Storm Forecasting via Deep Learning
Authors: Tasistro‐Hart Adrian , Grayver Alexander , Kuvshinov Alexey 
Published: December 2020

AbstractGeomagnetic storms, which are governed by the plasma magnetohydrodynamics of the solar‐interplanetary‐magnetosphere system, entail a formidable challenge for physical forward modeling. Yet, the abundance of high‐quality observational data has been amenable to the application of data‐hungry neural networks to geomagnetic storm forecasting. Almost all applications of neural networks to storm forecasting have utilized solar wind observations from the Earth‐Sun first Lagrangian point (L1) or closer and generated deterministic output without uncertainty estimates. Furthermore, forecasting work has focused on indices that are also sensitive to induced internal magnetic fields, complicating the forecasting problem with another layer of non‐linearity. We address these points, presenting neural networks trained on observations from both the solar disk and the L1 point. Our architecture generates reliable probabilistic forecasts over Est, the external component of the disturbance storm time index, showing that neural networks can gauge confidence in their output.
Identification of single motor units in skeletal muscle under low force isometric voluntary contractions using ultrafast ultrasound
Authors: Rohlén Robin , Stålberg Erik , Grönlund Christer 
Published: December 2020

AbstractThe central nervous system (CNS) controls skeletal muscles by the recruitment of motor units (MUs). Understanding MU function is critical in the diagnosis of neuromuscular diseases, exercise physiology and sports, and rehabilitation medicine. Recording and analyzing the MUs’ electrical depolarization is the basis for state-of-the-art methods. Ultrafast ultrasound is a method that has the potential to study MUs because of the electrical depolarizations and consequent mechanical twitches. In this study, we evaluate if single MUs and their mechanical twitches can be identified using ultrafast ultrasound imaging of voluntary contractions. We compared decomposed spatio-temporal components of ultrasound image sequences against the gold standard needle electromyography. We found that 31% of the MUs could be successfully located and their firing pattern extracted. This method allows new non-invasive opportunities to study mechanical properties of MUs and the CNS control in neuromuscular physiology.
Cynaroside inhibitsLeishmania donovaniUDP-galactopyranose mutase and induces reactive oxygen species to exert antileishmanial response
Authors: Tabrez Shams , Rahman Fazlur , Ali Rahat , Alouffi Abdulaziz S. , Akand Sajjadul Kadir , Alshehri Bader Mohammed , Alshammari Fahdah Ayed , Alam Aftab , Alaidarous Mohammed A. , Banawas Saeed , Dukhyil Abdul Aziz Bin , Rub Abdur 
Published: December 2020

AbstractCynaroside, a flavonoid, has been shown to have antibacterial, antifungal and anticancer activities. Here, we evaluated its antileishmanial properties and its mechanism of action through different in silico and in vitro assays. Cynaroside exhibited antileishmanial activity in time- and dose-dependent manner with 50% of inhibitory concentration (IC50) value of 49.49 ± 3.515 µM in vitro. It inhibited the growth of parasite significantly at only 20 µM concentration when used in combination with miltefosine, a standard drug which has very high toxicity. It also inhibited the intra-macrophagic parasite significantly at low doses when used in combination with miltefosine. It showed less toxicity than the existing antileishmanial drug, miltefosine at similar doses. Propidium iodide staining showed that cynaroside inhibited the parasites in G0/G1 phase of cell cycle. 2,7-dichloro dihydro fluorescein diacetate (H2DCFDA) staining showed cynaroside induced antileishmanial activity through reactive oxygen species (ROS) generation in parasites. Molecular-docking studies with key drug targets of Leishmania donovani showed significant inhibition. Out of these targets, cynaroside showed strongest affinity with uridine diphosphate (UDP)-galactopyranose mutase with −10.4 kcal/mol which was further validated by molecular dynamics (MD) simulation. The bioactivity, ADMET (absorption, distribution, metabolism, excretion and toxicity) properties, Organisation for Economic Co-operation and Development (OECD) chemical classification and toxicity risk prediction showed cynaroside as an enzyme inhibitor having sufficient solubility and non-toxic properties. In conclusion, cynaroside may be used alone or in combination with existing drug, miltefosine to control leishmaniasis with less cytotoxicity.
Indications for very high metallicity and absence of methane in the eccentric exo-Saturn WASP-117b
Authors: Carone Ludmila , Mollière Paul , Zhou Yifan , Bouwman Jeroen , Yan Fei , Baeyens Robin , Apai Dániel , Espinoza Nestor , Rackham Benjamin V. , Jordán Andrés , Angerhausen Daniel , Decin Leen , Lendl Monika , Venot Olivia , Henning Thomas 
Published: December 2020

Aims. We investigate the atmospheric composition of the long-period (Porb = 10 days) eccentric exo-Saturn WASP-117b. WASP-117b could be similar in atmospheric temperature and chemistry to WASP-107b. In mass and radius, WASP-117b is similar to WASP-39b, which allows a comparative study of these planets.
Methods. We analyzed a near-infrared transmission spectrum of WASP-117b taken with the Hubble Space Telescope (HST) WFC3 G141, which was reduced with two independent pipelines. High-resolution measurements were taken with VLT/ESPRESSO in the optical.
Results. We report the robust (3σ) detection of a water spectral feature. In a 1D atmosphere model with isothermal temperature, uniform cloud deck, and equilibrium chemistry, the Bayesian evidence of a retrieval analysis of the transmission spectrum indicates a preference for a high atmospheric metallicity [Fe/H] = 2.58−0.37+0.26 and clear skies. The data are also consistent with a lower metallicity composition [Fe/H] < 1.75 and a cloud deck between 10−2.2 and 10−5.1 bar, but with weaker Bayesian preference. We retrieve a low CH4 abundance of <10−4 volume fraction within 1σ and <2 × 10−1 volume fraction within 3σ. We cannot constrain the equilibrium temperature between theoretically imposed limits of 700 and 1000 K. Further observations are needed to confirm quenching of CH4 with Kzz ≥ 108 cm2 s−1. We report indications of Na and K in the VLT/ESPRESSO high-resolution spectrum with substantial Bayesian evidence in combination with HST data.
Semi-annual, annual and Universal Time variations in the magnetosphere and in geomagnetic activity: 4. Polar Cap motions and origins of the Universal Time effect
Authors: Lockwood Mike , Haines Carl , Barnard Luke A. , Owens Mathew J. , Scott Chris J. , Chambodut Aude , McWilliams Kathryn A. 
Published: December 2020

We use theam,an, asand theaσgeomagnetic indices to the explore a previously overlooked factor in magnetospheric electrodynamics, namely the inductive effect of diurnal motions of the Earth’s magnetic poles toward and away from the Sun caused by Earth’s rotation. Because the offset of the (eccentric dipole) geomagnetic pole from the rotational axis is roughly twice as large in the southern hemisphere compared to the northern, the effects there are predicted to be roughly twice the amplitude of those in the northern hemisphere. Hemispheric differences have previously been discussed in terms of polar ionospheric conductivities generated by solar photoionization, effects which we allow for by looking at the dipole tilt effect on the time-of-year variations of the indices. The electric field induced in a geocentric frame is shown to also be a significant factor and gives a modulation of the voltage applied by the solar wind flow in the southern hemisphere that is typically a ±30% diurnal modulation for disturbed intervals rising to ±76% in quiet times. For the northern hemisphere these are 15% and 38% modulations. Motion away from/towards the Sun reduces/enhances the directly-driven ionospheric voltages and reduces/enhances the magnetic energy stored in the tail and we estimate that approximately 10% of the effect appears in directly driven ionospheric voltages and 90% in changes of the rate of energy storage or release in the near-Earth tail. The hemispheric asymmetry in the geomagnetic pole offsets from the rotational axis is shown to be the dominant factor in driving Universal Time (UT) variations and hemispheric differences in geomagnetic activity. Combined with the effect of solar wind dynamic pressure and dipole tilt on the pressure balance in the near-Earth tail, the effect provides an excellent explanation of how the observed Russell-McPherron pattern with time-of-yearFandUTin the driving power input into the magnetosphere is converted into the equinoctialF-UTpattern in average geomagnetic activity (after correction is made for dipole tilt effects on ionospheric conductivity), added to a pronouncedUTvariation with minimum at 02–10 UT. In addition, we show that the predicted and observedUTvariations in average geomagnetic activity has implications for the occurrence of the largest events that also show the nettUTvariation.