An understanding of the normal state in the high-temperature superconducting cuprates is crucial to the ultimate understanding of the long-standing problem of the origin of the superconductivity ...itself. This so-called "strange metal" state is thought to be associated with a quantum critical point (QCP) hidden beneath the superconductivity. In electron-doped cuprates-in contrast to hole-doped cuprates-it is possible to access the normal state at very low temperatures and low magnetic fields to study this putative QCP and to probe the
➔ 0 K state of these materials. We report measurements of the low-temperature normal-state magnetoresistance (MR) of the n-type cuprate system La
Ce
CuO
and find that it is characterized by a linear-in-field behavior, which follows a scaling relation with applied field and temperature, for doping (
) above the putative QCP (
= 0.14). The magnitude of the unconventional linear MR decreases as
decreases and goes to zero at the end of the superconducting dome (
~ 0.175) above which a conventional quadratic MR is found. These results show that there is a strong correlation between the quantum critical excitations of the strange metal state and the high-
superconductivity.
Aims
β‐lactamase inhibitor resistance (BLIR) among the uropathogenic Escherichia coli (UPEC) minimizes treatment options. This study aimed to identify inhibitor‐resistant TEM (IRT) β‐lactamase that ...impart BLIR phenotype and explore non‐β‐lactams as alternative therapeutics.
Methods and Results
Thirty BLIR UPEC isolates were detected by Kirby–Bauer disc diffusion technique using β‐lactam–β‐lactamase inhibitor combination. Conjugal transfer of BLIR was successful from 17 isolates. PCR and sequencing of the TEM β‐lactamases from the transconjugants indicated 14 TEM‐84 (IRT) and three novel IRT variants (pUE184TEM, pUE203TEM, pUE210TEM). Three‐dimensional models of the latter were predicted and validated. Molecular docking of selected non‐β‐lactams (morin, catechin, naringenin triacetate) with the variants using AutoDock 4.2 showed comparable docking scores with significant hydrogen bond and hydrophobic interactions. Molecular dynamics simulation study confirmed stability of the non‐β‐lactams inside the catalytic pocket of the enzymes. Moreover, all three non‐β‐lactams were found to inhibit the purified TEM β‐lactamase variants in vitro. Microbroth dilution method indicated naringenin triacetate 64 μg ml−1 in combination with ceftazidime (CAZ) 30 μg ml−1 to be most effective against the BLIR transconjugants.
Conclusions
BLIR phenotypes were primarily attributed to the production of IRT β‐lactamases. Administration of the non‐β‐lactams with CAZ demonstrated an alternative therapeutic strategy against the IRT β‐lactamase producers.
Significance and Impact of the Study
This study indicates high risk of transmission of IRT β‐lactamases and suggests β‐lactam–non‐β‐lactam combination therapy to combat BLIR.
OBJECTIVE: The current study reviewed Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) variants for their effects on infection, transmission and neutralization by vaccine-induced ...antibodies. MATERIALS AND METHODS: The research articles for the current study were searched over PubMed, Google Scholar, EMBASE and Web of Science online databases. The keywords used were: (("SARS-CoV-2" OR "COVID-19") AND ("mutation" OR "variant") AND ("death" OR "hospitalization" OR "infection" OR "transmission") AND ("antibody" OR "neutralize" OR "vaccine")). A total of 333 research articles were retrieved through online-database search. These articles were further scrutinized for their relevancy. Additionally, searches were performed to find the latest relevant information over Google search engine and relevant news browsers. Finally, around 35 germane articles were considered for scripting the current report. RESULTS: The mutations have changed amino acids at key positions in spike protein viz. S477N, E484K, Q677H, E484Q, L452R, K417T, K417N and N501Y. These mutations are relevant for different characteristics and are present in newly evolved strains of SARS-CoV-2 like E484K in B.1.526, B.1.525, P.2, B.1.1.7, P.1 and B.1.351. Mutations have increased the immune escape potential leading to 3.5-6.5-folds decrease in neutralization of antibodies (Pfizer and Moderna vaccines). The variant, B.1.617 circulating in India and many other countries (double variant) having E484Q and L452R mutations, has raised the infection rate and decreased the neutralization capacity of the vaccine-induced antibodies. Deadly K417N+E484K+N501Y triplet mutations found in B.1.351 and P.1 have increased the transmission ability of these strains by 50% leading to greater COVID-19 hospitalization, ICU admissions and deaths. CONCLUSIONS: The new SARS-CoV-2 variants have compromised the neutralization potential of the currently used vaccines, but still, they have considerable efficacy to reduce infection and mortality.
https://www.europeanreview.org/wp/wp-content/uploads/Graphical_Abstract.jpg.
In the seamless forecast paradigm, it is hypothesized that the reduction in initial error in the dynamical model forecast would help to reduce forecast error in the extended range lead time up to 2–3 ...weeks. This hypothesis is tested in a version of an operational extended range forecast model based on National Centre for Environmental Prediction (US) Climate Forecast System version 2. Forecast skills are assessed to understand the role of initial errors on the prediction skill for Madden-Julian Oscillation (MJO). Retrospective forecasts are categorized in two groups. One group defines the lowest initial day’s error and the other with the highest initial day’s errors. Then, the error growth for these two categories is analyzed for the strong MJO events during May to September. The initial errors of MJO forecast are categorized and defined using the multivariate MJO index introduced by Wheeler and Hendon (Mon Wea Rev 132(8):1917–1932, 2004). The probability distribution of
bivariate root mean square error
(BVRMSE) and
error growth
evolution is used as metrics. The results showed that the initial error does not show any significant difference in the amplitude after a lead time of 7–10 days, and the error growth remains the same for both sets of runs. It is also found that the errors originate from the events with the initial phase in the western Pacific and the Indian Ocean. The study advocates the importance of better representation of MJO phases over the ocean in the model to improve the MJO prediction rather than simply focusing on improving the initial conditions.
Seismic attenuation of gas hydrate bearing sediments is estimated from the multi-channel seismic data acquired in Krishna–Godavari (KG) offshore basin in the vicinity of Site NGHP-01-10, where ∼128 m ...of fracture-filled hydrate is confirmed by drilling/coring, to understand the effect of gas hydrate on the seismic attenuation. The seismic quality factor (Q), which is the inverse of seismic attenuation, is estimated from two methods – first, the spectral ratio method which utilizes the logarithmic ratio of the seafloor and bottom simulating reflector (BSR) spectra; and second, the peak frequency method which depends upon the variations of the peak frequency of the BSR spectrum as a function of traveltime. In the study area, the complex fault system has perturbed the seafloor resulting in noisy seafloor spectrum. As a result, the logarithm of the spectral ratio was also noisy and the Q-values obtained from spectral ratio method were found to be unstable. On the other hand, the peak frequency method is found to be relatively stable as it depends only on the peak frequency of the BSR which can be reliably obtained by conventional processing. This method yields an effective Q value of BSR which represents a weighted average of the interval Q-values of the water column and the gas hydrate bearing sediments. Since the Q-value of water column can be treated as a constant, the variations in effective Q-value can be interpreted in terms of the variations of Q in the gas hydrate bearing sediments for a constant thickness of water column.
The estimated effective Q-values, along the inline and crossline seismic profiles, depend on several factors such as gas hydrate, free gas and the complex fault system. The combined interpretation of the quality factor and the interval velocity model helps to understand these effects in different zones of the seismic data. The attenuation of the background marine sediments is estimated from the analysis of crossline seismic profile. The gas hydrate bearing sediments, as inferred from the velocity model, show low attenuation as compared to that of the background sediments. In contrast, active migration of free gas across the fault system leads to increase in seismic attenuation within the gas hydrate stability zone. The complex fault zone may also lead to an increase in seismic attenuation. The blanked seismic zone shows a marginal decrease in seismic attenuation probably related to load-bearing form of gas hydrate. Our attenuation results are compared against the results obtained from waveform inversion, albeit with a higher resolution. The relative variation of Q estimated from the proposed method is close to the average Q-values estimated from full waveform inversion for most of the CDPs. The proposed methodology can be a useful technique to estimate seismic attenuation from multi-channel seismic data.
•Peak frequency method: an effective technique for Q-estimation.•Low attenuation for gas hydrate bearing sediments.•High attenuation for free gas bearing faults and complex fault zone.
Introduction
Metritis is an uterine pathology that causes economic losses for the dairy industry. It is associated with lower reproductive efficiency, increased culling rates, decreased milk ...production and increased veterinary costs.
Objectives
To gain a more detailed view of the urine metabolome and to detect metabolite signature in cows with metritis. In addition, we aimed to identify early metabolites which can help to detect cows at risk to develop metritis in the future.
Methods
We used nuclear magnetic resonance spectroscopy starting at 8 and 4 weeks prior to the expected day of parturition, during the week of diagnosis of metritis, and at 4 and 8 weeks after diagnosis of metritis in Holstein dairy cows.
Results
At 8 weeks before parturition, pre-metritic cows had a total of 30 altered metabolites. Interestingly, 28 of them increased in urine when compared with control cows (P < 0.05). At 4 weeks before parturition, 34 metabolites were altered. At the week of diagnosis of metritis a total of 20 metabolites were altered (P < 0.05). The alteration continued at 4 and 8 weeks after diagnosis.
Conclusions
The metabolic fingerprints in the urine of pre-metritic and metritic cows point toward excretion of multiple amino acids, tricarboxylic acid cycle metabolites and monosaccharides. Combination of galactose, leucine, lysine and panthotenate at 8 weeks before parturition might serve as predictive biomarkers for metritis.
The implementation of a bias‐correction and signal amplification technique to the National Center for Environmental Prediction's Climate Forecast System‐based Grand Ensemble Prediction System ...Multi‐Model Ensemble outputs is studied for improvements in track predictions of three cyclonic storms over North Indian Ocean. Bias‐correction method involves the removal of lead‐dependent climatological bias from multi‐model ensemble forecasts by using European Centre for Medium‐Range Weather Forecasts Re‐analysis (ERA‐Interim) daily‐averaged data sets as observations. The corrected data are then subjected to signal amplification procedure involving a two‐point space and time correction of ensembles based on the leading signal (ensemble mean), whereby large uncertainties and disagreements between different model outputs are reduced. Results show that bias‐correction and signal amplification technique is, indeed, improving the track forecasts of selected cyclonic storm cases with significant reduction in track errors even at longer lead times.
Plain Language Summary
Cyclonic storms forming over warm North Indian Ocean region, which track toward land, are major threats to vast growing and thickly populated coastal communities of Indian Peninsula. Proper prediction of the storm formation and track as well as providing an advance warning on its development can aid the public in better planning and disaster management. This study introduces a technique of bias‐correction and signal amplification for improving early storm‐track forecasts, which can be applied on tracks of cyclones predicted by combining multiple climate model ensembles. Three storms, which formed over Bay of Bengal basin in 2013, are studied, and corrected tracks using this technique along with uncorrected track from models are compared with observations. Results show that corrected tracks are more matching with the observations than uncorrected tracks with reduced track errors for all cases studied even for predictions from more than a week before storm‐genesis.
Key Points
A bias‐correction and signal amplification method is applied on a Climate Forecast System‐based Multi‐Model Ensemble Prediction outputs
Analyses indicate significant improvement in cyclone track prediction and reduction in track errors even at longer lead times
Results are of socio‐economic importance and vital to the field of tropical cyclone track prediction
Lameness is a very important disorder of periparturient dairy cows with implications on milk production and composition as well as with consequences on reproductive performance. The aetiology of ...lameness is not clear although there have been various hypotheses suggested over the years. The objective of this study was to metabotype the urine of dairy cows prior to, during and after the onset of lameness by evaluating at weeks -8, -4 pre-calving, the week of lameness diagnosis, and +4 and +8 weeks post-calving. We used a metabolomics approach to analyse urine samples collected from dairy cows around calving (6 cows with lameness v. 20 healthy control cows). A total of 153 metabolites were identified and quantified using an in-house MS library and classified into 6 groups including: 11 amino acids (AAs), 39 acylcarnitines (ACs), 3 biogenic amines (BAs), 84 glycerophospholipids, 15 sphingolipids and hexose. A total of 23, 36, 40, 23 and 49 metabolites were observed to be significantly different between the lame and healthy cows at -8 and -4 weeks pre-calving, week of lameness diagnosis as well as at +4 and +8 weeks post-calving, respectively. It should be noted that most of the identified metabolites were elevated; however, a few of them were also lower in lame cows. Overall, ACs and glycerophospholipids, specifically phosphatidylcholines (PCs), were the metabolite groups displaying the strongest differences in the urine of pre-lame and lame cows. Lysophosphatidylcholines (LysoPCs), although to a lesser extent than PCs, were altered at all time points. Alterations in urinary AA concentrations were also observed during the current study for four time points. During the pre-calving period, there was an observed elevation of arginine (-8 week), tyrosine (-8 week) and aspartate (-4 week), as well as a depression of urinary glutamate (-4 weeks). In the current study, it was additionally observed that concentrations of several sphingomyelins and one BA were altered in pre-lame and lame cows. Symmetric dimethylarginine was elevated at both -8 weeks pre-calving and the week of lameness diagnosis. Data showed that urinary fingerprinting might be a reliable methodology to be used in the future to differentiate lame cows from healthy ones.
TiO2 thin films deposited by electron beam evaporation technique annealed in either O2 or Ar atmosphere showed ferromagnetism at room temperature. The pristine amorphous film demonstrates anatase ...phase after annealing under Ar/O2 atmosphere. While the pristine film shows a super-paramagnetic behavior, both O2 and Ar annealed films display hysteresis at 300K. X-ray photo emission spectroscopy (XPS), Raman spectroscopy, Rutherford’s backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) were used to refute the possible role of impurities/contaminants in magnetic properties of the films. The saturation magnetization of the O2 annealed film is found to be higher than the Ar annealed one. It is revealed from shifting of O 1s and Ti 2p core level spectra as well as from the enhancement of high binding energy component of O 1s spectra that the higher magnetic moment is associated with higher oxygen vacancies. In addition, O2 annealed film demonstrates better crystallinity, uniform deposition and smoother surface than that of the Ar annealed one from glancing angle X-ray diffraction (GAXRD) and atomic force microscopy (AFM). We conclude that although ferromagnetism is due to oxygen vacancies, the higher magnetization in O2 annealed film could be due to crystallinity, which has been observed earlier in Co doped TiO2 film deposited by pulsed laser deposition (Mohanty et al., 2012 10).
•TiO2 films were deposited by e-beam evaporation technique and post annealed under O2/Ar at 500°C.•The pristine film shows SPM behavior where as O2 and Ar annealed films demonstrate RTFM.•The presence of magnetic impurities has been discarded by various characterization techniques.•The magnetic moment is found to be higher in O2 annealed film than the Ar annealed one.•The higher Ms in O2 annealed film is attributed to oxygen vacancies as well as crystallinity.
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