HIV-1 did not contribute to the 2019-nCoV genome

When a new pathogen that causes a global epidemic in humans, one key question is where it comes from. This is especially important for a zoonotic infectious disease that jumps from animals to humans. Knowing the origin of such a pathogen is critical to develop means to block further transmission and to develop vaccines. Discovery of the origin of a newly human pathogen is a sophisticated process that requires extensive and vigorous scientific validations and generally takes many years, such as the cases for HIV-1, SARS and MERS. Unfortunately, before the natural sources of new pathogens are clearly defined, conspiracy theories that the new pathogens are man-made often surface as the source. However, in all cases, such theories have been debunked in history

Closed-form Approximation for Performance Bound of Finite Blocklength Massive MIMO Transmission

Ultra-reliable low latency communications (uRLLC) is adopted in the fifth generation (5G) mobile networks to better support mission-critical applications that demand high level of reliability and low latency. With the aid of well-established multiple-input multiple-output (MIMO) information theory, uRLLC in the future 6G is expected to provide enhanced capability towards extreme connectivity. Since the latency constraint can be represented equivalently by blocklength, channel coding theory at finite block-length plays an important role in the theoretic analysis of uRLLC. On the basis of Polyanskiy's and Yang's asymptotic results, we first derive the exact close-form expressions for the expectation and variance of channel dispersion. Then, the bound of average maximal achievable rate is given for massive MIMO systems in ideal independent and identically distributed fading channels. This is the study to reveal the underlying connections among the fundamental parameters in MIMO transmissions in a concise and complete close-form formula. Most importantly, the inversely proportional law observed therein implies that the latency can be further reduced at expense of spatial degrees of freedom

Effect of different binders on the electrochemical performance of metal oxide anode for lithium-ion batteries

When testing the electrochemical performance of metal oxide anode for lithium-ion batteries (LIBs), binder played important role on the electrochemical performance. Which binder was more suitable for preparing transition metal oxides anodes of LIBs has not been systematically researched. Herein, five different binders such as polyvinylidene fluoride (PVDF) HSV900, PVDF 301F, PVDF Solvay5130, the mixture of styrene butadiene rubber and sodium carboxymethyl cellulose (SBR+CMC), and polyacrylonitrile (LA133) were studied to make anode electrodes (compared to the full battery). The electrochemical tests show that using SBR+CMC and LA133 binder which use water as solution were significantly better than PVDF. The SBR+CMC binder remarkably improve the bonding capacity, cycle stability, and rate performance of battery anode, and the capacity retention was about 87% after 50th cycle relative to the second cycle. SBR+CMC binder was more suitable for making transition metal oxides anodes of LIBs

On the Road to 6G: Visions, Requirements, Key Technologies and Testbeds

Fifth generation (5G) mobile communication systems have entered the stage of commercial development, providing users with new services and improved user experiences as well as offering a host of novel opportunities to various industries. However, 5G still faces many challenges. To address these challenges, international industrial, academic, and standards organizations have commenced research on sixth generation (6G) wireless communication systems. A series of white papers and survey papers have been published, which aim to define 6G in terms of requirements, application scenarios, key technologies, etc. Although ITU-R has been working on the 6G vision and it is expected to reach a consensus on what 6G will be by mid-2023, the related global discussions are still wide open and the existing literature has identified numerous open issues. This paper first provides a comprehensive portrayal of the 6G vision, technical requirements, and application scenarios, covering the current common understanding of 6G. Then, a critical appraisal of the 6G network architecture and key technologies is presented. Furthermore, existing testbeds and advanced 6G verification platforms are detailed for the first time. In addition, future research directions and open challenges are identified for stimulating the on-going global debate. Finally, lessons learned to date concerning 6G networks are discussed

Is Low-Volume High-Intensity Interval Training a Time-Efficient Strategy to Improve Cardiometabolic Health and Body Composition? A Meta-Analysis

The present meta-analysis aimed to assess the effects of low-volume high-intensity interval training (LV-HIIT; i.e., ≤5 min high-intensity exercise within a ≤15-min session) on cardiometabolic health and body composition. A systematic search was performed in accordance with PRISMA guidelines to assess the effect of LV-HIIT on cardiometabolic health and body composition. Twenty-one studies (moderate to high quality) with a total of 849 participants were included in this meta-analysis. LV-HIIT increased cardiorespiratory fitness (CRF, SMD=1.19 [0.87, 1.50]) while lowering systolic blood pressure (SMD=-1.44 [-1.68, -1.20]), diastolic blood pressure (SMD=-1.51 [-1.75, -1.27]), mean arterial pressure (SMD=-1.55 [-1.80, -1.30]), MetS z-score (SMD=-0.76 [-1.02, -0.49]), fat mass (kg) (SMD=-0.22 [-0.44, 0.00]), fat mass (%) (SMD=-0.22 [-0.41, -0.02]), and waist circumference (SMD= -0.53 [-0.75, -0.31]) compared to untrained control (CONTROL). Despite a total time-commitment of LV-HIIT of only 14-47% and 45-94% compared to moderate-intensity continuous training and HV-HIIT, respectively, there were no statistically significant differences observed for any outcomes in comparisons between LV-HIIT and moderate-intensity continuous training (MICT) or high-volume HIIT. Significant inverse dose–responses were observed between the change in CRF with LV-HIIT and sprint repetitions (β=−0.52 [-0.76, -0.28]), high-intensity duration (β=−0.21 [-0.39, -0.02]), and total duration (β=−0.19 [-0.36, -0.02]), while higher intensity significantly improved CRF gains. LV-HIIT can improve cardiometabolic health and body composition and represent a time-efficient alternative to MICT and HV-HIIT. Performing LV-HIIT at a higher intensity drives higher CRF gains. More repetitions, longer time at high-intensity, and total session duration did not augment gains in CRF

Toward 6G TKμ\mu Extreme Connectivity: Architecture, Key Technologies and Experiments

Sixth-generation (6G) networks are evolving towards new features and order-of-magnitude enhancement of systematic performance metrics compared to the current 5G. In particular, the 6G networks are expected to achieve extreme connectivity performance with Tbps-scale data rate, Kbps/Hz-scale spectral efficiency, and $\mu$s-scale latency. To this end, an original three-layer 6G network architecture is designed to realise uniform full-spectrum cell-free radio access and provide task-centric agile proximate support for diverse applications. The designed architecture is featured by super edge node (SEN) which integrates connectivity, computing, AI, data, etc. On this basis, a technological framework of pervasive multi-level (PML) AI is established in the centralised unit to enable task-centric near-real-time resource allocation and network automation. We then introduce a radio access network (RAN) architecture of full spectrum uniform cell-free networks, which is among the most attractive RAN candidates for 6G TK$\mu$ extreme connectivity. A few most promising key technologies, i.e., cell-free massive MIMO, photonics-assisted Terahertz wireless access and spatiotemporal two-dimensional channel coding are further discussed. A testbed is implemented and extensive trials are conducted to evaluate innovative technologies and methodologies. The proposed 6G network architecture and technological framework demonstrate exciting potentials for full-service and full-scenario applications.Comment: 15 pages, 12 figure

Identification of Milk Component in Ancient Food Residue by Proteomics

Proteomic approaches based on mass spectrometry have been recently used in archaeological and art researches, generating promising results for protein identification. Little information is known about eastward spread and eastern limits of prehistoric milking in eastern Eurasia.In this paper, an ancient visible food remain from Subeixi Cemeteries (cal. 500 to 300 years BC) of the Turpan Basin in Xinjiang, China, preliminarily determined containing 0.432 mg/kg cattle casein with ELISA, was analyzed by using an improved method based on liquid chromatography (LC) coupled with MALDI-TOF/TOF-MS to further identify protein origin. The specific sequence of bovine casein and the homology sequence of goat/sheep casein were identified.The existence of milk component in ancient food implies goat/sheep and cattle milking in ancient Subeixi region, the furthest eastern location of prehistoric milking in the Old World up to date. It is envisioned that this work provides a new approach for ancient residue analysis and other archaeometry field

One-pot aqueous synthesis of cysteine-capped CdTe/CdS core-shell nanowires

Highly fluorescent cysteine-capped CdTe/CdS core-shell nanowires were successfully synthesized by reacting CdCl2 with NaHTe in aqueous solution under refluxing at 100 °C for 140 min. On increasing the reaction time from 10 to 140 min, CdTe/CdS nanocrystals gradually grew into nanorods and eventually completely evolved into nanowires. The nanowires have amino and carboxyl functional groups on their surfaces and can be well dispersed in aqueous solution. The as-prepared CdTe/CdS nanowires show a fluorescence quantum yield (QY) of 7.25 % due to the unique nature of cysteine and the formation of a CdS shell on the surface of the CdTe core, they have a narrower diameter distribution (d = ~5 nm) and a length in the range of 175-275 nm, and their aspect ratio is between 1/35 and 1/55

Ring-Opening Polymerization of l-Lactic Acid O-Carboxyanhydrides Initiated by Alkoxy Rare Earth Compounds

The ring-opening polymerization of l-lactic acid O-carboxyanhydrides was initiated by triisopropoxyneodymium in toluene-THF mixtures. Typically, high yields and relatively high molecular weight PLAs were obtained within 4 h at 25 °C. The reaction was highly controllable and easy to conduct, and the molecular weight distribution of the PLAs was rather narrow (Mw/Mn = 1.10–1.36). NMR analysis showed that one end of the PLA chain consisted of an isopropoxy group, while the other end of the chain contained a hydroxyl group. Due to their availability and high polymerizability, Lac-OCAs are promising monomers for the preparation of tailored architectures derived from well-defined PLAs