bluuebunny/crossref_metadata_2025 huggingface dataset:
Prognostic impact of hospital‐acquired disability in elderly patients with heart failure
Authors: Saitoh Masakazu , Takahashi Yuta , Okamura Daisuke , Akiho Mitsutoshi , Suzuki Hidetoshi , Noguchi Naoki , Yamaguchi Yukito , Hori Kentaro , Adachi Yuichi , Takahashi Tetsuya
Published: April 2021

Aims

Functional decline is associated with worse outcomes in patients with elderly heart failure (HF), but little is known about the prognostic impact of hospital‐acquired disability (HAD) during hospital stay after acute HF. The present study examines the prognostic significance of HAD in the prediction of all‐cause mortality in elderly patients who admitted for acute HF.

Methods and results

This retrospective study was performed in 1941 elderly patients aged ≥65 years or older from the cardiovascular physiotherapy for acute HF patients in the Tokyo metropolitan area registry and excluded those who died in hospital. HAD was defined as any decline in the Barthel index (BI) before discharge compared with the BI within 1 month before hospital admission. The primary outcome of this study was all‐cause death and HF readmission. A total of 565 (29%) deaths and 789 (41%) HF readmission occurred over a median follow‐up period of 1.7 years. A total of 476 patients (25%) had HAD during hospital stay after acute HF. In multivariable analysis, HAD predicted all‐cause death [hazard ratio (HR): 1.772; 95% confidence interval (CI): 1.450–2.167; P < 60; 0.001] and with risk of HF readmission (HR: 1.193; 95% CI: 1.005–1.416; P = 0.043) after adjusting for the Meta‐analysis Global Group in Chronic Heart Failure risk score.

Conclusions

Hospital‐acquired disability is associated with an increased risk of all‐cause death and readmission for HF in elderly patients with acute HF.
Effect of slope tower angle and thermal storage media on flexibility solar chimney power plant performance
Authors: Semai Hakim , Bouhdjar Amor
Published: April 2021

Floating tower projects in solar chimney power plant are emerging with considerable interest. However, high chimney tower might be under great pressure from wind blow. Use of flexible fabric material for the tower might reduce the constraint on the chimney and reduce the cost. The present work is devoted to the study of the solar tower inclination impact on the efficiency of the solar chimney power plant (SCPP). The considered inclination angles of the tower are 15°, 22°, and 30°. In addition, waterbed is laid down on the ground of the collector to store heat. Results showed that a tower inclination of up to 22° might improve the performance of the SCPP. The extra heat storage also made a better use of the energy. This improved the power produced from sunset to sunrise with a lower entropy generation, mainly in the configuration with a solar tower inclination between 15° and 22°.
A comprehensive survey of physical layer security over fading channels: Classifications, applications, and challenges
Authors: Yadav Poonam , Kumar Sandeep , Kumar Rajesh
Published: April 2021

Due to the open nature of wireless communication systems, the data transmission over these networks are vulnerable to malicious attack. To safeguard the transmitted data, physical layer security (PLS) has been emerged as a promising technique because of its unique feature of utilizing randomness of the wireless channel to secure the information. The preeminent idea of utilizing the channel imperfections such as fading and noise into the security providing resource is the basic approach behind PLS. For exploiting the randomness of the propagation medium, the analysis of the secrecy performance over the fading channel is of utmost importance. With the explanation of basic theory and technology, this paper presents an elaborated survey on the PLS research over the fading channels. To exploit the performance gains, we discuss the optimization approaches in different network design problems, for example, secrecy rate maximization, power minimization, and secure energy efficiency problems. We present a comparative study of the expressions of various performance metrics of the PLS along with classification depending upon the channel state information of the eavesdropper. The application and challenges of the PLS in the emerging wireless technologies are also reviewed and discussed. This paper incorporates almost all the aspects of PLS implemented over the fading channels. Furthermore, the paper is concluded with open research directions for the PLS system in various fields that can be explored to design a flexible and robust security system to satisfy the security requirements of the next‐generation networks.
HPV73 in cervical cancer and distribution of HPV73 variants in cervical dysplasia
Authors: Borgfeldt Christer , Söderlund‐Strand Anna , Flygh Lotten Darlin , Forslund Ola
Published: April 2021

HPV73 is classified as possibly oncogenic and is not recognized by most commercial primary HPV screening platforms. The aim was to determine the prevalence of HPV73 among invasive cervical cancers, formalin‐fixed paraffin embedded (FFPE) samples (N = 69), from southern Sweden during 2009 to 2010. Another aim was to determine proportions of HPV73 among Aptima HPV assay negative cervical cancers (N = 9, out of 206 cancers) and of high‐grade cytological cervical diagnosis (N = 75, out of 5807 high grade lesions) in liquid‐based cytology (LBC) samples collected between 2016 and 2019. We also investigated the distribution of HPV73 variants A1, A2 and B among HPV73‐positive cases. HPV73 was detected by multiplex MGP‐PCR and Luminex, and HPV73 variants were identified by sequencing PCR amplicons. HPV73 was detected in 2.9% (2/69, 95% CI: 0.18‐9.9) of the FFPE cervical cancer series. Among the Aptima HPV‐negative LBC samples, HPV73 was present in 55.5% (5/9) of the cancers and 29.3% (22/75) of the different grades of cervical diagnosis. The A1, A2 and B variants were present in 6.9% (2/29), 82.7% (24/29) and 10.3% (3/29) of the HPV73‐positive women, respectively. Among the seven HPV73 cancer cases (two FFPE samples and five LBC samples), six A2 and one A1 isolate were detected. In summary, the A2 variant of HPV73 was most common in our region. In addition, the observed prevalence of HPV73 (2.9%) in cervical cancers and its relative high occurrence (55.5%) among Aptima HPV‐negative cancers urge that detection of HPV73 should be included in future primary HPV screening programs.
Atherogenic Dyslipidemia After Liver Transplantation: Mechanisms and Clinical Implications
Authors: Syed Taseen , Siddiqui Mohammad S.
Published: April 2021

Cardiovascular disease (CVD), particularly atherosclerosis‐associated CVD, is a major cause of long‐term mortality after liver transplantation (LT). The liver is central in lipid homeostasis, and changes associated with insulin resistance, weight gain, adipose tissue inflammation, and development of nonalcoholic fatty liver disease (NAFLD) after LT promote atherogenesis. These factors synergistically alter lipid homeostasis, thereby leading to the production of proatherogenic lipoproteins, which contribute to the heighted risk of CVD‐associated events observed in LT recipients. Although the exact mechanism promoting this shift of a proatherogenic lipoprotein profile is currently not known, the choice of immunosuppression and preexisting metabolic risk factors (ie, NAFLD) are likely contributors. This shift in proatherogenic lipoprotein subparticles presents clinical challenges as the traditional lipid profile employed in clinical practice may not fully capture this atherogenic risk. This review focuses on lipoprotein metabolism and atherogenesis in LT recipients.
The effect of front‐of‐package nutrition labels on the choice of low sugar products
Authors: Mauri Chiara , Grazzini Laura , Ulqinaku Aulona , Poletti Erika
Published: April 2021

Policy makers around the world are facing serious challenges in controlling citizens' obesity and healthiness, hence, they devote increased attention to the development of tools that communicate easily processable nutrition information. Front‐of‐package nutrition labels are one of such tools and have been used to signal the extent to which food items contain potentially unhealthy ingredients such as sugar or fat. In this research, we focus on sugar cues on three different food categories to investigate their impact on consumer choice. We compare two labels, one already used (traffic‐light) and one never used (sugar teaspoon): sugar teaspoons prove to be more effective than the previously used traffic‐lights in healthy product choices, but only for specific food categories. In two experiments, we find that sugar teaspoon labels indicating sugar content, as opposed to traffic‐light labels, are more effective in signaling sugar levels and thus, in helping consumers making healthier choices. We find that this is particularly relevant for food categories that have a simpler ingredient composition (i.e., whose healthiness relies more heavily on sugar). We finally propose processing fluency as the mechanism for the relation between sugar signals and product choices.
Response surface methodology optimised solvothermal system enables an efficient extraction of echinacoside and oleuropein from Syringa pubescens Turcz
Authors: Wu Yanfang , Chu Yindi , Yang Qinyu , Li Mengjia , Yu Miao , Deng Ruixue , Liu Kun , Wang Xinsheng , Fan Enguo
Published: April 2021

Introduction

Syringa pubescens Turcz. was reported to be abundant in the Funiu Mountains of Henan Province and can be used to treat hepatitis and cirrhosis. In order to develop and utilise the resource, a fast and simple technique to extract bioactive compounds is needed.

Objectives

Our aims were to provide an extraction technique of glycosides from S. pubescens and study the antioxidant activity of this material.

Methods

Box–Behnken design (BBD) was employed with three factors at three levels. The process parameters such as ethanol concentration (X1), temperature (X2), and solvent–solid ratio (X3) could significantly influence efficiency and yield of target compounds. High‐performance liquid chromatography (HPLC) was used to determine the content of glycosides. DPPH (α,α‐diphenyl‐β‐picrylhydrazyl), ABTS (2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) and reducing power were used to evaluate the antioxidant activity of S. pubescens extract.

Results

The optimal parameters for the maximal extraction yield were obtained with ethanol concentration of 68%, temperature of 89°C, solvent–solid ratio of 46 mL/g, and time of 20 min. The S. pubescens extract showed strong antioxidant properties in vitro.

Conclusion

The findings indicated the potential application of solvothermal extraction method to extract bioactive compounds from S. pubescens Turcz. Furthermore, the S. pubescens extract could be used as an important resource of antioxidant activity.
Managing orchard groundcover to reduce pollinator foraging post‐bloom
Authors: McDougall Robert , DiPaola Anna , Blaauw Brett , Nielsen Anne L
Published: April 2021

BACKGROUND

Agricultural insecticides are believed to play a role in global pollinator decline. In mass‐flowering orchard crops, recommendations to reduce exposure of pollinators to insecticides include spraying at periods when bees aren't foraging, such as dusk and dawn and outside of crop flowering times. However, the presence of flowering weeds within orchards mean pollinators may still be found foraging throughout the growing season, increasing the likelihood that exposure will still occur. We hypothesized that removing these weeds within orchard groundcover may reduce pollinator foraging post‐bloom and thus reduce exposure of this group to pesticides. We tested this hypothesis by using herbicide to remove flowering broadleaf weeds in the sod middles (‘groundcover’) between rows of a nectarine orchard in New Jersey, USA, and assessing the effect on pollinator visitation via three different methods.

RESULTS

Significantly lower abundance, richness, diversity, and evenness of pollinators were found in plots where herbicide treatment had removed the majority of flowering weeds, compared to untreated plots. This was the case for bees, and for pollinators overall, and was reflected in both visual observations and active sampling through sweep netting. Passive sampling with blue vane traps failed to detect a difference between treatments.

CONCLUSION

Groundcover management in orchards is often employed as part of integrated pest management programs to remove alternative host plants of insect pests. The findings of this study show that it is also effective in reducing post‐bloom pollinator foraging in orchards, thus potentially preventing exposure of these beneficial organisms to harmful insecticides. © 2021 Society of Chemical Industry.
Forcing mechanism of the Silk Road pattern and the sensitivity of Rossby‐wave source hotspots to mean‐state winds
Authors: Li Ronald Kwan Kit , Tam Chi‐Yung , Lau Ngar‐Cheung , Sohn Soo‐Jin , Ahn Joong‐Bae , O'Reilly Christopher
Published: April 2021

The Silk Road pattern (SRP) is a leading mode of Eurasian atmospheric variability in boreal summer. It remains challenging for many models to predict the temporal phase of the SRP. This study investigates whether the forcing mechanism of the SRP can explain SRP prediction difficulty. Rossby‐wave sources (RWS) associated with the SRP are first identified in a reanalysis. An idealised barotropic model is then used to test wave propagation from all identified RWS, to isolate the relevant forcing locations of the SRP, namely the RWS hotspots. In addition to previous findings, a new hotspot in the central North Pacific is located, which can force the SRP by westward dispersion of a zonally elongated Rossby wave. Furthermore, a new mechanism of the Indian summer monsoon in forcing the SRP is discovered. Results also suggest that Rossby‐wave propagation by itself only explains a small fraction of the SRP amplitude, consistent with baroclinic energy conversion from the mean state, which has previously been shown to be vital for SRP growth—not represented in the idealised model. Seasonal hindcasts from the Pusan National University (PNU) coupled general circulation model are also analysed. The hindcasts can predict the SRP spatially but not temporally. Within a seasonal timescale, the hindcast develops an upper‐level mean‐state wind bias compared with the reanalysis, which is shown by the barotropic model to affect RWS hotspot locations of the SRP. While the reanalysis SRP is associated with North Atlantic sea‐surface temperature (SST) anomalies, the hindcast SRP is associated with tropical Pacific SST. Wind biases in the North Atlantic jet exit, subtropical western Pacific, and tropical Pacific are found to alter wave propagation from the North Atlantic and the North and tropical Pacific, respectively, and can explain the association of the SRP with different SSTs in the reanalysis and hindcast. This sensitivity of hotspots to mean‐state winds is proposed to reduce SRP prediction skill.
Non‐adiabatic dynamic of atmospheric unimolecular photochemical reactions of 4,4‐difluoro‐crotonaldehyde using TD‐DFT and TSH approaches
Authors: Castro Pedro J. , Maeda Satoshi , Morokuma Keiji
Published: April 2021

Photochemical reactions of small molecules occur upon irradiation by ultraviolet or visible light, and they are a very important chemical processes in the Earth's atmosphere because they impact our quality of life and health. Small‐unsaturated carbonyl compounds play an important role in the chemistry of the polluted troposphere. The fluorinated aldehydes are very reactive under the sunlight driving to species that trigger more atmospheric reactions. This paper is focused on a theoretical study of the photochemistry of difluoro‐crotonaldehyde using static and dynamic calculations by combination of global reaction route mapping and trajectory surface hopping approach. The static analysis of the electronic and geometrical structures at the critical points allowed to rationalize the possible pathways that interconnect the stationary and crossing points in order to get a map of the unimolecular photochemical reactions which take place. The time evolution of the electronic states and the degrees of freedom enabled the identification of the requirements to follow the most probable deactivation pathways. This article reports the unimolecular deactivation pathways after the electronic excitation of the trans and cis isomers. In both cases, the excitation energies were calculated and compared with the analogues in the crotonaldehyde in order to elucidate the effect of fluorine atoms on the electronic structure and stabilities. After the initial excitations to the ππ* excited states, the main deactivation channels follow non‐adiabatic pathways via S1/S0 conical intersections. Ultrafast processes leading to the early activation of the S1 govern the decay of the difluoro‐crotonaldehyde. Depending on the nature of the S1 state before the crossing with the S0, the system can follow several reaction pathways. The main photochemical processes observed were the cis‐trans isomerization, the Norrish type I reaction (α‐cleavage), Norrish type II reaction (γ‐hydrogen abstraction) and fluorine photodissociation. The time scale, the molecular deformations and the electronic states implied for the different photochemical processes, as well as how these compete with the photophysical deactivation are discussed.
Sustainable tourism development and globalization: Recent insights from the United States
Authors: Sharif Arshian , Ullah Subhan , Shahbaz Muhammad , Mahalik Mantu Kumar
Published: April 2021

Our study explores the relationship between tourism and globalization (both overall, and in terms of three sub‐indices, namely economic, social, and political globalization) in the United States (US) using monthly data from January 1995 to December 2017. We employ the quantile‐on‐quantile (QQ) regression technique for our analysis. The sample period of the present study allows the separate examination of the relationship between globalization and tourism both before the global financial crisis (1995–2007) and after (2008–2017). The findings suggest that in the US during the precrisis era, all the globalization indices and tourism are positively bidirectionally related. During the postcrisis period, all globalization indices positively affect tourism, but tourism has a negative effect on economic and political globalization. The theoretical and policy implications of the empirical findings are discussed.
[1,2]‐Shift in Chiral Ni(II) Schiff‐Base Derivatives: Conversion of α‐ Thiobenzylated Amino Acid into the Cysteine Derivative
Authors: Levitskiy Oleg A. , Grishin Yuri K. , Magdesieva Tatiana V.
Published: April 2021

The first example of the anionic [1,2]‐shift taking place in the metal coordination environment is described. The α‐thiobenzylated glycine in the form of the Ni(II) Schiff‐base complex is converted into the corresponding cysteine derivative with ca 70 % yield. The reaction disclosed emphasizes how the reactivity of a substrate can be influenced by noncovalent interactions in the metal coordination environment.
Bifunctional Spatiotemporal Metasurfaces for Incident Angle‐Tunable and Ultrafast Optically Switchable Electromagnetically Induced Transparency
Authors: Hu Yuze , Tong Mingyu , Xu Zhongjie , Cheng Xiangai , Jiang Tian
Published: April 2021

Advances in tunable metamaterials/metasurfaces facilitates their utilization in novel optical components, and lead to many breakthroughs in light tailoring by giving birth to diverse spatiotemporal dynamics. In the ascendant field of terahertz (THz) photonics, the ultrafast modulation is the fundamental process of technological advancements in high‐speed wireless communications, sensing, and imaging. However, the current research efforts have been mainly devoted to studies of single functionality under the control of one stimulus, which has plateaued in terms of innovative new features. Here, building on the incident angle‐induced C2 symmetry breaking of split ring pairs, we experimentally demonstrate extremely versatile, ultrafast THz switching behaviors at continuously alterable resonant states. The direction‐controlled resonance hybridization provides another excellent degree of routing freedom, owing to its robustness, simplicity, and wide tunability. By leveraging such virtues, single LC mode and EIT‐like resonance under normal and oblique incidence conditions are both effectively switched‐off by means of photon injection. Considering the ultrashort lifetime of free carriers in MoSe2 crystal, the corresponding transient dynamics show an ultrafast recovery time within 700 ps. The strategy proposed here is a viable pathway for multidimensional THz wave manipulation, which gears up a crucial step for diversified functionalities in deployable metaphotonic devices.
Wafer‐Scale Oxygen‐Doped MoS2 Monolayer
Authors: Wei Zheng , Tang Jian , Li Xuanyi , Chi Zhen , Wang Yu , Wang Qinqin , Han Bo , Li Na , Huang Biying , Li Jiawei , Yu Hua , Yuan Jiahao , Chen Hailong , Sun Jiatao , Chen Lan , Wu Kehui , Gao Peng , He Congli , Yang Wei , Shi Dongxia , Yang Rong , Zhang Guangyu
Published: April 2021

Monolayer MoS2 is an emergent 2D semiconductor for next‐generation miniaturized and flexible electronics. Although the high‐quality monolayer MoS2 is already available at wafer scale, doping of it uniformly remains an unsolved problem. Such doping is of great importance in view of not only tailoring its properties but also facilitating many potential large‐scale applications. In this work, the uniform oxygen doping of 2 in wafer‐scale monolayer MoS2 (MoS2−xOx) with tunable doping levels is realized through an in situ chemical vapor deposition process. Interestingly, ultrafast infrared spectroscopy measurements and first‐principles calculations reveal a reduction of bandgaps of monolayer MoS2−xOx with increased oxygen‐doping levels. Field‐effect transistors and logic devices are also fabricated based on these wafer‐scale MoS2−xOx monolayers, and excellent electronic performances are achieved, exhibiting promise of such doped MoS2 monolayers.
Bond and re‐anchoring tests of post‐tensioned steel tendon in case of strand failure inside cement grouting with voids
Authors: Asp Olli , Tulonen Joonas , Kuusisto Lauri , Laaksonen Anssi
Published: April 2021

Grouted tendons are commonly used in construction of bridges and other post‐tensioned structures. The quality of grouting is essential to provide the durability and robustness of the structure. In this paper, the bond and re‐anchoring of post‐tensioned tendons in grout in case of tendon failure is assessed. A set of tests were conducted to simulate the failure of a post‐tensioned tendon in the beam. The results were compared with the theory of prestressing strand anchoring in concrete. In the tests, the re‐anchoring and bond lengths were measured in case of complete grout and incomplete grout with void. In the case of incomplete grout, the increase in re‐anchoring length is observed. In the case of overlapping re‐anchoring and bond length, the bond length and tendon slip increase significantly. A limited re‐anchoring length of tendon in incomplete grout increases the robustness of the structure, as the broken tendon can maintain its effectiveness outside of the failure region. The existing calculation model shows a good match with test results, and therefore it is suitable for the analysis of structures with broken tendons.
Expanding the boundaries of ligand–target modeling by exascale calculations
Authors: Bolnykh Viacheslav , Rossetti Giulia , Rothlisberger Ursula , Carloni Paolo
Published: April 2021

Molecular simulations and molecular docking are widely used tools to investigate ligand/target interactions and in drug design. High‐performance computing (HPC) is boosting both the accuracy and predictive power of these approaches. With the advent of exascale computing, HPC may become standardly applied in many drug design campaigns and pharmacological applications. This review discusses how innovative HPC algorithms and hardware are being exploited in current simulations and docking codes, pointing also at some of the limitations of these approaches. The focus is on technical aspects which might not be all that familiar to the computational pharmacologist.

This article is categorized under:

Software > Molecular Modeling

Software > Simulation Methods

Structure and Mechanism > Computational Biochemistry and Biophysics
W algebras, cosets and VOAs for 4d $$ \mathcal{N} $$ = 2 SCFTs from M5 branes
Authors: Xie Dan , Yan Wenbin
Published: April 2021

Abstract

We identify vertex operator algebras (VOAs) of a class of Argyres-Douglas (AD) matters with two types of non-abelian flavor symmetries. They are the W algebras defined using nilpotent orbit with partition [qm, 1s]. Gauging above AD matters, we can find VOAs for more general $$ \mathcal{N} $$
N
= 2 SCFTs engineered from 6d (2, 0) theories. For example, the VOA for general (AN − 1, Ak − 1) theory is found as the coset of a collection of above W algebras. Various new interesting properties of 2d VOAs such as level-rank duality, conformal embedding, collapsing levels, coset constructions for known VOAs can be derived from 4d theory.
The Transcendental and the Agonistic: A Media Philosophy Perspective
Authors: Barker Timothy
Published: April 2021

This critical response to Dominic Smith’s ‘Taking Exception: Philosophy of Technology as a Multidimensional Problem Space’ begins by outlining the key contributions of his essay, namely his insightful approach to the transcendental, on the one hand, and his introduction of the topological problem space as an image for thought, on the other. The response then suggests ways of furthering this approach by addressing potential reservations about determinism. The response concludes by suggesting a way out of these questions of determinism by thinking the transcendental in concert with the agonistic.
Decision support system for ranking relevant indicators for reopening strategies following COVID-19 lockdowns
Authors: Almulhim Tarifa S. , Barahona Igor
Published: April 2021

The pandemic caused by the spread of the SARS-CoV-2 virus forced governments around the world to impose lockdowns, which mostly involved restricting non-essential activities. Once the rate of infection is manageable, governments must implement strategies that reverse the negative effects of the lockdowns. A decision support system based on fuzzy theory and multi-criteria decision analysis principles is proposed to investigate the importance of a set of key indicators for post-COVID-19 reopening strategies. This system yields more reliable results because it considers the hesitation and experience of decision makers. By including 16 indicators that are utilized by international organizations for comparing, ranking, or investigating countries, our results suggest that governments and policy makers should focus their efforts on reducing violence, crime and unemployment. The provided methodology illustrates the suitability of decision science tools for tackling complex and unstructured problems, such as the COVID-19 pandemic. Governments, policy makers and stakeholders might find in this work scientific-based guidelines that facilitate complex decision-making processes.
Material parametrization of natural rubber based compound and characterization of crack propagation under consideration of dissipative effects
Authors: Pornhagen Dan , Schneider Konrad , Stommel Markus
Published: April 2021

Most concepts to characterize crack propagation were developed for elastic materials. When applying these methods to elastomers, the question is how the inherent energy dissipation of the material affects the cracking behavior. This contribution presents a numerical analysis of crack growth in natural rubber taking energy dissipation due to the visco-elastic material behavior into account. For this purpose, experimental tests were first carried out under different load conditions to parameterize a Prony series as well as a Bergström–Boyce model with the results. The parameterized Prony series was then used to perform numerical investigations with respect to the cracking behavior. Using the FE-software system ANSYS and the concept of material forces, the influence and proportion of the dissipative components were discussed.
Prototethyan Accretionary Orogenesis Along the East Gondwana Periphery: New Insights From the Early Paleozoic Igneous and Sedimentary Rocks in the Sibumasu
Authors: Wang Yuejun , Qian Xin , Cawood Peter A. , Zhang Yuzhi , Wang Yang , Xing Xiaowan , Senebouttalath Vongpaseuth , Gan Chengshi
Published: April 2021

New geochronological and geochemical data document a new and widely distributed succession of igneous and sedimentary rocks within the Sibumasu that extend from SW Yunnan through SE Asia as far as Sumatra. Our data revealed the presence of an Ordovician‐Silurian (mainly ∼490–430 Ma) igneous zone. The early Paleozoic granites in the zone display similar elemental and Sr–Nd–Pb–Hf isotopic compositions. They were derived from a common mixed source of ancient crustal materials with a juvenile component and formed in a subduction‐related setting. Detrital‐zircon U‐Pb apparent ages from the previously defined Precambrian Lancang and Ximeng units in the SW Yunnan portion of the Sibumasu are in the range of 3,306–428 Ma and 3,316–512 Ma, with the youngest age‐peaks of 505 Ma and 447 Ma, respectively, indicating the lower Paleozoic (Cambrian‐Silurian) sedimentary sequences. The Tarutao Unit and its equivalents in the SE Asia portion of the Sibumasu yield the U‐Pb apparent ages of 3,177–510 Ma, suggesting the maximum deposited time being Cambrian‐Ordovician. All these detrital zircon U‐Pb ages define two main peaks of ∼554–528 Ma and 964–905 Ma with εHf(t) values similar to those in the Qiangtang, Tethyan Himalaya, and eastern Indochina. The lower Paleozoic detritus in the Sibumasu were likely derived from the India‐Antarctica region of East Gondwana. We propose that the late Cambrian‐Silurian units formed in an outward‐propagating accretionary orogen in response to the consumption of the Prototethyan Ocean in SW Yunnan and SE Asia. Sibumasu might represent a part of the easterly migrating accretionary orogen along the northern margin of East Gondwana in the late Cambrian‐late Silurian.
Variations in the Characteristic Amplitude of Tectonic Tremor Induced by Long‐Term Slow Slip Events
Authors: Nakamoto Keita , Hiramatsu Yoshihiro , Matsuzawa Takanori , Mizukami Tomoyuki
Published: April 2021

Long‐term slow slip events (L‐SSEs) often excite short‐term slow slips events (S‐SSEs) and tectonic tremor in the zone of episodic tremor and slip (ETS). However, the factors controlling the occurrence of primary versus excited tremor events remain unclear. To elucidate these factors, we analyzed tectonic tremor events in and around the Bungo Channel (Nankai subduction zone), where L‐SSEs are known to excite tremor and S‐SSEs in the ETS zone. We focused on the spatial distribution of the characteristic amplitude (CA) of tremor, determined from the duration‐amplitude distributions of tremor events, as an indicator of the properties of the tremor source. CAs are large in L‐SSE slip areas and small in adjacent areas. The difference between CA values during tremor‐excitation periods (L‐SSEs) and the intervening periods (ΔCA) is positive in the slip area, negative in adjacent areas, and tends toward zero in the far field. We suggest that the heterogeneous distributions of CA and ΔCA reflect the heterogeneous effective strengths of tremor patches, which might be related to petrological properties, and stress and pore‐fluid pressure variations induced by L‐SSEs, respectively. The upward migration of fluid from the ETS zone along the plate interface might modulate the effective stress and strength states of tremor patches during L‐SSEs.
Winter Air‐Sea CO2 Fluxes Constructed From Summer Observations of the Polar Southern Ocean Suggest Weak Outgassing
Authors: Mackay Neill , Watson Andrew
Published: April 2021

The Southern Ocean plays an important role in the global oceanic uptake of CO2. Estimates of the air‐sea CO2 flux are made using the partial pressure of CO2 at the sea surface (), but winter observations of the region historically have been sparse, with almost no coverage in the Pacific or Indian ocean sectors south of the Polar front in the period 2004–2017. Here, we use summertime observations of relevant properties in this region to identify subsurface waters that were last in contact with the atmosphere in the preceding winter, and then reconstruct “pseudo observations” of the wintertime . These greatly improve wintertime coverage south of the Polar Front in all sectors, improving the robustness of flux estimates there. We add the pseudo observations to other available observations of and use a multiple linear regression to produce a gap‐filled time‐evolving estimate of from which we calculate the air‐sea flux. The inclusion of the pseudo observations increases outgassing at the beginning of the period, but the effect reduces with time. We estimate a 2004–2017 long‐term mean flux of −0.02 ± 0.02 Pg C yr−1 for the Southern Ocean south of the Polar Front, similar to comparable studies based on shipboard data. However, we diverge somewhat from an estimate which utilized autonomous float data for recent years: we find a small sink in 2017 of −0.08 ± 0.03 Pg C yr−1 where the float‐based estimate suggested a small source.
Perturbation of Urbanization to Earth's Surface Energy Balance
Authors: Shen Pengke , Zhao Shuqing , Ma Yongjing
Published: April 2021

Urbanization, one of the most dramatic forms of land conversion, modifies local climatic environments and threatens human life and health. Here we use the space‐for‐time approach combined with satellite data to quantify the potential perturbation of surface energy balance and land surface temperature (LST) caused by urbanization at global scale. We estimate that collectively +2.4°C, +0.9°C, and +1.7°C potential changes for annual daytime, nighttime, and mean LST could be triggered when land surface converted from natural area to urban use, due primarily to the decline of latent heat during months from April to October (−23.9–−3.2 W m−2), and the reduced sensible heat and ground heat storage in other months (−5.2–−2.4 W m−2). Urbanization perturbation to surface energy balance and temperature exhibit conspicuous spatial heterogeneity (i.e., varying with latitude and climate zones) and temporal asymmetries (i.e., diurnal and seasonal: strong in summer daytime and weak in winter nighttime). These spatial‐temporal variations are interrelated closely with local background climate‐vegetation regimes, as indicated by strong correlations between urbanization perturbation to surface biophysical effects and precipitation, temperature, vegetation index across regions and months. Our findings provide empirical evidence that biophysical mechanisms of urbanization need to be considered in predicting future trajectories of climate change and local susceptibility of surface energy balance should be accounted for when evaluating urbanization effects and mitigating urban heat.
Explicit IMF By‐Dependence in Geomagnetic Activity: Quantifying Ionospheric Electrodynamics
Authors: Holappa L. , Robinson R. M. , Pulkkinen A. , Asikainen T. , Mursula K.
Published: April 2021

Geomagnetic activity is mainly driven by the southward (Bz) component of the interplanetary magnetic field (IMF), which dominates all solar wind coupling functions. Coupling functions also depend on the absolute value of the dawn‐dusk (By) component of the IMF, but not on its sign. However, recent studies have shown that for a fixed level of solar wind driving, auroral electrojets in the Northern Hemisphere (NH) are stronger for By > 0 than for By < 0 during NH winter. In NH summer, the dependence on the By sign is reversed. While this By sign dependence, also called the explicit By‐dependence, is very strong in the winter hemisphere, it is weak in the summer hemisphere. Moreover, the explicit By‐dependence is much stronger in the westward electrojet than in the eastward electrojet. In this study, we study how the explicit IMF By‐dependence is coupled with large‐scale field‐aligned currents (FACs) by using FAC measurements from the Active Magnetosphere and Planetary Electrodynamics Response Experiment and an empirical ionospheric conductance model. We model the complete ionospheric electrodynamics by solving the current continuity equation, and show that during periods of elevated solar wind driving (Bz < 0), the IMF By component modulates Regions 1 and 2 FACs in the dawn sector of the winter hemisphere. This leads to an explicit By‐dependence in ionospheric conductance and the westward electrojet. We also show that the By‐dependence of FACs and conductance is weak in the dusk sector, which explains the earlier observation of the weak By‐dependence of the eastward electrojet.
Fourier domain excision of periodic radio frequency interference
Authors: Maan Yogesh , van Leeuwen Joeri , Vohl Dany
Published: April 2021

The discovery and study of pulsars and fast radio bursts (FRBs) in time-domain radio data is often hampered by radio frequency interference (RFI). Some of this terrestrial RFI is impulsive and bright, and relatively easy to identify and remove. Other anthropogenic signals, however, are weaker yet periodic, and their persistence can drown out astrophysical signals. Here we show that Fourier-domain excision of periodic RFI is an effective and powerful step in detecting weak cosmic signals. We find that applying the method significantly increases the signal-to-noise ratio of transient and periodic pulsar signals. In live studies we detected single pulses from pulsars and FRBs that would otherwise have remained buried in background noise. We show the method has no negative effects on pulsar pulse shape, and that it enhances timing campaigns. We demonstrate the method on real-life data from a number of large radio telescopes, and conclude that Fourier-domain RFI excision increases the effective sensitivity to astrophysical sources by a significant fraction, which can be even larger than an order of magnitude in the case of strong RFI. An accelerated implementation of the method runs on standard time-domain radio data formats and is publicly available.
Reactive GRASP for the Prize-collecting Covering Tour Problem
Authors: Clímaco Glaubos , Rosseti Isabel , Silva Rogérioda , Guerine Marcos
Published: April 2021

This paper presents a Greedy Randomized Adaptive Search Procedure (GRASP) for the Prize-Collecting Covering Tour Problem (PCCTP), which is the problem of finding a route for traveling teams that provide services to communities geographically distant from large urban locations. We devised a novel hybrid heuristic by combining a reactive extension of the GRASP with Random Variable Neighborhood Search (VND) meta-heuristic for the purpose of solving the PCCTP. Computational experiments were conducted on a PCCTP benchmark from the literature, and the results demonstrate our approach provides a significant improvement in solving PCCTP and comparable with the state-of-the-art, mainly regarding the computational processing time.
Bringing human‐animal interaction to sport: Potential impacts on athletic performance
Authors: Marvin Sutton , Sorenson Kennet , Stevens Jeffrey R.
Published: April 2021

To gain an edge in performance, athletes, coaches, trainers, and sport psychologists worldwide leverage findings from psychological research to develop training and performance strategies. The field of sport psychology draws upon research on stress, anxiety, mindfulness, and team building to develop these strategies. Here, we introduce human‐animal interaction as a potential area of research that may apply to athletic performance. Structured interactions with animals—particularly therapy dogs—can provide physiological benefits associated with stress and the oxytocin system, psychological benefits for anxiety and motivation, and social benefits through social support. Yet these effects have not yet been systematically investigated in athletes. Integration of human‐animal interactions into athletics can occur through animal visitation programmes and resident therapy animal programmes. Integrating human‐animal interactions into athletics presents some unique challenges and limitations that must be considered before implementing these programmes, and these interactions are not a panacea that will work in every situation. But, given the amount of human‐animal interaction research suggesting benefits in medicine, mental health, and education contexts, it is worthwhile exploring potential benefits not just for athletic performance, but also for injury prevention and recovery.

Highlights

Human–animal interaction is a potential area of research that may apply to athletic performance.

Structured interactions with animals can provide physiological, psychological, and social benefits to athletes, through it is not a panacea that will work in every situation.

Integrating human–animal interactions into athletics presents some unique challenges and limitations that must be considered before implementing these programs.
Controlled human exposures to diesel exhaust: a human epigenome-wide experiment of target bronchial epithelial cells
Authors: Cardenas Andres , Fadadu Raj P , Van Der Laan Lars , Ward-Caviness Cavin , Granger Louis , Diaz-Sanchez David , Devlin Robert B , Bind Marie-Abèle
Published: April 2021

Diesel exhaust (DE) is a major contributor to ambient air pollution around the world. It is a known human carcinogen that targets the respiratory system and increases risk for many diseases, but there is limited research on the effects of DE exposure on the epigenome of human bronchial epithelial cells. Understanding the epigenetic impact of this environmental pollutant can elucidate biological mechanisms involved in the pathogenesis of harmful DE-related health effects. To estimate the causal effect of short-term DE exposure on the bronchial epithelial epigenome, we conducted a controlled single-blinded randomized crossover human experiment of exposure to DE and used bronchoscopy and Illumina 450K arrays for data collection and analysis, respectively. Of the 13 participants, 11 (85%) were male and 2 (15%) were female, and 12 (92%) were White and one (8%) was Hispanic; the mean age was 26 years (SD = 3.8 years). Eighty CpGs were differentially methylated, achieving the minimum possible exact P-value of P = 2.44 × 10−4 (i.e. 2/213). In regional analyses, we found two differentially methylated regions (DMRs) annotated to the chromosome 5 open reading frame 63 genes (C5orf63; 7-CpGs) and unc-45 myosin chaperone A gene (UNC45A; 5-CpGs). Both DMRs showed increased DNA methylation after DE exposure. The average causal effects for the DMRs ranged from 1.5% to 6.0% increases in DNA methylation at individual CpGs. In conclusion, we found that short-term DE alters DNA methylation of genes in target bronchial epithelial cells, demonstrating epigenetic level effects of exposure that could be implicated in pulmonary pathologies.
Extragenic suppressors of Schizosaccharomyces pombe rad9 mutations uncouple radioresistance and hydroxyurea sensitivity from cell cycle checkpoint control.
Authors: Lieberman H B
Published: April 2021

Schizosaccharomyces pombe cells that contain a mutation within rad9 are sensitive to ionizing radiation, UV light and hydroxyurea, relative to wild-type strains. In addition, the mutants are moderately hypomutable by UV and unable to delay initiation of mitosis after treatment with radiation or hydroxyurea. Three radioresistant derivatives of rad9::ura4 cells were isolated, and each contained a single unique extragenic suppressor responsible for the acquired resistance. The suppressor loci also conferred radioresistance upon cells containing rad9-192, which differs from rad9+ by a single base pair change. The suppressors additionally enhanced the radioresistance of cells containing rad3-136, a mutation that leads to phenotypes similar to those mediated by rad9::ura4. None of the derivatives of rad9::ura4 cells recovered the ability to delay cycling in G2 after exposure to ionizing radiation or UV light. All three suppressor derivatives, relative to the parental rad9::ura4 strain, also exhibited a moderate increase in resistance to the DNA replication inhibitor hydroxyurea without gaining the ability to stop progression into mitosis despite the inhibition of DNA synthesis. Results are discussed in terms of models to explain the putative role of rad9 and the suppressor genes in promoting radioresistance and mediating checkpoint controls responsive to DNA damage or incomplete DNA replication.
Genetic analysis of the colicin V secretion pathway.
Authors: Zhang L H , Fath M J , Mahanty H K , Tai P C , Kolter R
Published: April 2021

Colicin V (ColV) is peptide antibiotic secreted by Escherichia coli through a dedicated exporter composed of three proteins, CvaA, CvaB, and TolC. ColV secretion is independent of the E. coli general secretory pathway (Sec) but requires an N-terminal export signal specific for the CvaAB/TolC exporter. ColV secretion was characterized using genetic and biochemical methods. When the ColV N-terminal extension is replaced with the OmpA signal sequence, the Sec system can localize ColV to the periplasm. Periplasmic ColV is lethal to cells lacking the ColV immunity protein, Cvi. Based on this result, a genetic assay was designed to monitor for the presence of periplasmic ColV during normal CvaAB/TolC mediated secretion. Results indicate that low levels of ColV may be present in the periplasm during secretion. Precursor and mature ColV were also characterized from the wild-type system and in various exporter mutant backgrounds using immunoprecipitation. ColV processing is rapid in wild-type cells, and CvaA and CvaB are critical for processing to occur. In contrast, processing occurs normally, albeit more slowly, in a TolC mutant.
5 S rRNA is involved in fidelity of translational reading frame.
Authors: Dinman J D , Wickner R B
Published: April 2021

Chromosomal mutants (maintenance of frame = mof) in which the efficiency of -1 ribosomal frameshifting is increased can be isolated using constructs in which lacZ expression is dependent upon a -1 shift of reading frame. We isolate a new mof mutation, mof9, in Saccharomyces cerevisiae and show that it is complemented by both single and multi-copy 5 S rDNA clones. Two independent insertion mutations in the rDNA locus (rDNA::LEU2 and rDNA::URA3) also display the Mof- phenotype and are also complemented by single and multi-copy 5 S rDNA clones. Mutant 5 S rRNAs expressed from a plasmid as 20-50% of total 5 S rRNA in a wild-type host also induced the Mof- phenotype. The increase in frameshifting is greatest when the lacZ reporter gene is expressed on a high copy, episomal vector. No differences were found in 5 S rRNA copy number or electrophoretic mobilities in mof9 strains. Both mof9 and rDNA::LEU2 increase the efficiency of +1 frameshifting as well but have no effect on readthrough of UAG or UAA termination codons, indicating that not all translational specificity is affected. These data suggest a role for 5 S rRNA in the maintenance of frame in translation.