A new study published by the journal Aging & Disease reported that intravenous administration of clinical-grade human mesenchymal stem cells (MSCs) into patients with coronavirus disease 2019 ...(COVID-19) resulted in improved functional outcomes (
). This study demonstrated that intravenous infusion of MSCs is a safe and effective approach for treating patients with COVID-19 pneumonia, including elderly patients displaying severe pneumonia. COVID-19 is a severe acute respiratory illness caused by a new coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, treating COVID-19 patients, particularly those afflicted with severe pneumonia, is challenging as no specific drugs or vaccines against SARS-CoV-2 are available. Therefore, MSC therapy inhibiting the overactivation of the immune system and promoting endogenous repair by improving the lung microenvironment after the SARS-CoV-2 infection found in this study is striking. Additional studies in a larger cohort of patients are needed to validate this therapeutic intervention further, however.
Metal sulfides are of great interest for future electrode materials in supercapacitor and solar cell applications owing to their superior electrochemical activity and excellent electrical ...conductivity. With this scope, a binary transition metal sulfide (CoS) is prepared via one-step hydrothermal synthesis. Hexagonal phase of CoS with space group of P6
/mmc(194) is confirmed by XRD analysis. Additional cubic Co
S
phase in the prepared sample originates the mixed valence state of Co (Co
and Co
) is affirmed from XPS analysis. Morphological features are visualized using HRSEM images that shows nanoflower shaped star-anise structure. Employing the prepared CoS as active electrode material, interfacial charge transport kinetics is examined by EIS-Nyquist plot. The supercapacitive performances are tested in two and three-electrode system which exhibited respective specific capacitances of 57 F/g and 348 F/g for 1 A/g. Further, the fabricated asymmetric CoS//AC supercapacitor device delivers an appreciable energy density of 15.58 Wh/kg and power density of 700.12 W/kg with excellent cyclic stability of 97.9% and Coulombic efficiency of 95% over 2000 charge-discharge cycles. In addition, dye-sensitized solar cells are fabricated with CoS counter electrode and the obtained power conversion efficiency of 5.7% is comparable with standard platinum based counter electrode (6.45%). Curie-Weiss plot confirms the transition of paramagnetic nature into ferrimagnetic behavior at 85 K and Pauli-paramagnetic nature at 20 K respectively. Temperature dependent resistivity plot affirms the metallic nature of CoS sample till 20 K and transition to semiconducting nature occurs at <20 K owing to Peierl's transition effect.
Abstract
Both seasonal and annual mean precipitation and evaporation influence patterns of water availability impacting society and ecosystems. Existing global climate studies rarely consider such ...patterns from non-parametric statistical standpoint. Here, we employ a non-parametric analysis framework to analyze seasonal hydroclimatic regimes by classifying global land regions into nine regimes using late 20th century precipitation means and seasonality. These regimes are used to assess implications for water availability due to concomitant changes in mean and seasonal precipitation and evaporation changes using CMIP5 model future climate projections. Out of 9 regimes, 4 show increased precipitation variation, while 5 show decreased evaporation variation coupled with increasing mean precipitation and evaporation. Increases in projected seasonal precipitation variation in already highly variable precipitation regimes gives rise to a pattern of “seasonally variable regimes becoming more variable”. Regimes with low seasonality in precipitation, instead, experience increased wet season precipitation.
ABSTRACT
In recent years, large radio surveys of active galactic nuclei, comprising millions of sources, have become available where one could investigate dipole asymmetries, assumedly arising due to ...a peculiar motion of the Solar system. Investigations of such dipoles have yielded in past much larger amplitudes than the cosmic microwave background (CMB) dipole, though their directions seem to lie close to the CMB dipole. Here we investigate dipole asymmetries in two recent large radio surveys, Very Large Array sky survey (VLASS) containing 1.9 million sources, covering the sky north of −40° declination, and the Rapid ASKAP Continuum Survey (RACS) containing 2.1 million sources, covering the sky south of +30° declination We find dipoles determined from the VLASS and RACS surveys to be significantly larger than the CMB dipole. Dipole directions from the VLASS and RACS data differ significantly from each other. Nevertheless, along with a number of other previously determined dipoles, including the CMB, they all appear to lie in a narrow sky region, which argues for the various dipoles to be related somehow. However, significant differences in their derived peculiar velocities, including that of the CMB, cannot be explained by a peculiar motion of the Solar system, which should necessarily be a single value. Instead, their discordant peculiar velocities may be indicating that different cosmic reference frames are moving relative to each other or that the matter distribution on cosmic scales is not homogeneous and isotropic, either scenario being in contravention of what expected from the cosmological principle.
The angular distribution of the cosmic microwave background radiation (CMBR) in the sky shows a dipole asymmetry, ascribed to the peculiar velocity of the observer (or rather of the Solar system), ...where peculiar velocity is defined as motion relative to the local comoving coordinates. The peculiar velocity thus determined turns out to be 370 km s−1 in the direction RA=168°, Dec=−7°. On the other hand, a dipole asymmetry in the sky distribution of radio sources in the NRAO VLA Sky Survey (NVSS), carried out by the Very Large Array (VLA) of the National Radio Astronomy Observatory (NRAO), comprising a catalog of 1.8 million sources, yielded a value for the observer's velocity approximately four times larger than the CMBR value, though the direction turned out to be in agreement with that of the CMBR dipole. This large difference in the observer's speeds with respect to the reference frames of NVSS radio sources and of CMBR, confirmed since by many independent groups, is rather disconcerting, as the observer's motion with respect to local comoving coordinates should be independent of the technique used to determine it. A genuine difference in relative speeds of two cosmic reference frames could jeopardize the cosmological principle; thence, it is crucial to confirm such discrepancies using independent samples of radio sources. We investigate here the dipole in the sky distribution of radio sources in the recent TIFR GMRT Sky Survey (TGSS), carried out by the Giant Metrewave Radio Telescope (GMRT) of the Tata Institute of Fundamental Research (TIFR), comprising a dataset of 0.62 million sources, to determine the observer's motion. We find a significant disparity in the observer's speeds relative to all three reference frames, determined from the radio source datasets and the CMBR, which does not fit with the cosmological principle, a starting point for the standard modern cosmology.
The lack of proper understanding of multi-layer soil moisture (SM) profile (signals) remains a persistent challenge in sustainable agricultural water management and food security, especially during ...drought conditions. We develop a machine-learning algorithm using the concept of learning from patterns to estimate the multi-layer SM information in ungauged locations firmly based on local knowledge of the climatic and landscape controls. The Contiguous United States (CONUS) is clustered into homogeneous regions based on the association between SM and climate and landscape controls. Extreme Gradient Boosting (XGBoost) algorithm is applied to homogenous regions to capture the complex relationship between appropriate predictor variables and in-situ SM at multiple layers over the CONUS. Soil Moisture Active Passive (SMAP) Level 4 (L4) surface (0–5 cm) and rootzone (0–100 cm) SM along with climate and landscape datasets are used as predictor variables. In-situ multi-layer SM recorded by Soil Climate Analysis Network (SCAN), Snow Telemetry (SNOTEL), and U.S. Climate Reference Network (USCRN) networks are utilized as predictands. XGBoost models are then trained region-wise and layer-wise to estimate multi-layer SM information at 5, 10, 20, 50, and 100 cm depths (five layers) at 1-km spatial resolution. Results indicate that the predictor variables have varying levels of influence on SM with changing soil depth, and meteorological variables have the least importance. Validation at 79 independent locations indicates the multi-layer SM estimates successfully capture temporal dynamics of SM, with most locations achieving ubRMSE less than 0.04 m3/m3. The high-resolution SM estimates offer spatial sub-grid heterogeneity compared to SMAP L4 SM.
•New method proposed to estimate multi-layer daily Soil Moisture (SM) over the CONUS.•SM estimated at 1 km resolution across 5 soil depths 5, 10, 20, 50, and 100 cm.•Machine learning model trained with landscape and climate variables to estimate SM.•Relative importance of predictors assessed across the five soil layers.•Spatio-temporal SM estimates at five layers are produced with reasonable accuracy.
ABSTRACT
We determine here the peculiar motion of the Solar system, first time from the m–z Hubble diagram of quasars. Observer’s peculiar motion causes a systematic shift in the m–z plane between ...sources lying along the velocity vector and those in the opposite direction, providing a measure of the peculiar velocity. Accordingly, from a sample of ∼1.2 × 105 mid-infrared quasars with measured spectroscopic redshifts, we arrive at a peculiar velocity ∼22 times larger than that from the cosmic microwave background radiation (CMBR) dipole but direction matching within ∼2σ. Previous findings from number count, sky brightness, or redshift dipoles observed in samples of distant active galactic nuclei or supernovae type Ia too had yielded values 2–10 times larger than the CMBR value, though the direction in all cases agreed with the CMBR dipole. Since a genuine solar peculiar velocity cannot vary from one data set to another, an order of magnitude, statistically significant, discordant dipoles might imply that we may instead have to look for some other cause for the genesis of these dipoles, including that of the CMBR. At the same time, a common direction for all these dipoles, determined from completely independent surveys by different groups employing different techniques, might indicate that these dipoles are not resulting from some systematics in the observations or in the data analysis, but could instead suggest a preferred direction in the Universe due to an inherent anisotropy, which, in turn, would be against the cosmological principle, the most basic tenet of the modern cosmology.
ABSTRACT
Peculiar motion of the Solar system, determined from the dipole anisotropy in the Cosmic Microwave Background Radiation (CMBR), has given a velocity 370 km s−1 along RA = 168°, Dec. = −7°. ...Subsequent peculiar motion determinations from the number counts, sky brightness, or redshift dipoles observed in large samples of distant radio galaxies and quasars yielded peculiar velocities 2 to 10 times larger than CMBR, though in all cases the directions matched with the CMBR dipole. Here, we introduce a novel technique for determining the peculiar motion from the magnitude-redshift (mB–z) Hubble diagram of Type Ia Supernovae (SN Ia), one of the best standard candles available. We find a peculiar velocity 1.6 ± 0.5 × 103 km s−1, larger than the CMBR value roughly by a factor of four, along RA = 173° ± 12°, Dec. = 10° ± 9°, the direction being within $\stackrel{\lt }{_{\sim }}2\sigma$ of the CMBR dipole. Since a genuine solar motion would not depend upon the method or the data set employed, large discrepancies seen among various dipole amplitudes could imply that these dipoles, including the CMBR one, might not pertain to observer’s peculiar motion. However, a common direction for various dipoles might indicate a preferred direction in the Universe, implying an intrinsic anisotropy, in violation of the cosmological principle, a cornerstone of the modern cosmology.
•Review the remote sensing application for food security.•Aspects of crop growth, irrigation, and crop losses are considered.•Crop growth: crop yield and LAI estimation.•Irrigation: mapping irrigated ...areas, and quantification of irrigation water.•Crop losses: pests, diseases, crop lodging, and weeds.
The global population is expected to reach 9.8 billion by 2050. There is an exponential growth of food production to meet the needs of the growing population. However, the limited land and water resources, climate change, and an increase in extreme events likely to pose a significant threat for achieving the sustainable agriculture goal. Given these challenges, food security is included in the United Nations’ Sustainable Development Goals (SDGs). Since the advent of Sputnik, followed by the Explorer missions, satellite remote sensing is assisting us in collecting the data at global scales. In this work, we review how satellite remote sensing information is utilized to assess and manage agriculture, an important component of ecohydrology. Overall, three critical aspects of agriculture are considered: (a) crop growth and yield through empirical models, physics-based models, and data assimilation in crop models, (b) applications pertaining to irrigation, which include mapping irrigation areas and quantification of irrigation, and (c) crop losses due to pests, diseases, crop lodging, and weeds. The emphasis is on satellite sensors in optical, thermal, microwave, and fluorescence frequencies. We conclude the review with an outlook of challenges and recommendations. This paper is the first of a two-part review series. The second part reviews the role of satellite remote sensing in water security, wherein we discuss the aspects of water quality and quantity along with extremes (floods and droughts).
ABSTRACT
We investigate dipole asymmetries in four large radio surveys, each spanning more than 75 per cent of the sky. Two of them, the Very Large Array Sky Survey (VLASS) and the Rapid ASKAP ...Continuum Survey (RACS), have recently yielded dipoles that appear incongruent with each other as well as seem inconsistent with previous radio survey dipoles and the cosmic microwave background (CMB) dipole. Because these radio surveys have large overlaps in sky coverage, comprising hence large majority of common radio sources, one would not expect significant differences between their radio dipoles, irrespective of their underlying source of origin. We examine here in detail these radio dipoles, to ascertain the source of incongruency among them. We find the VLASS and RACS data to be containing some declination-dependent systematics, seemingly in the vicinity of the declination limit of each survey. We show that the effects of such systematics can be mitigated by restricting the declination limits of the respective survey during the dipole determination. A weighted mean of the sky coordinates of thus derived dipoles from the four radio surveys lies within 1.2σ of the CMB dipole direction. However, the amplitude appears significantly larger, 3.7 ± 0.6 times or more than the CMB dipole. This puts in doubt not only the conventional wisdom that the genesis of all these dipoles, including that of the CMB dipole, is due to the Solar peculiar motion, it also raises uncomfortable questions about the Cosmological Principle, the basis of the standard ΛCDM cosmological model.
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