The hydrolytic processes occurring at the surface of silicon nitride (Si3N4) bioceramic have been indicated as a powerful pathway to instantaneous inactivation of SARS-CoV-2 virus. However, the virus ...inactivation mechanisms promoted by Si3N4 remain yet to be elucidated. In this study, we provide evidence of the instantaneous damage incurred on the SARS-CoV-2 virus upon contact with Si3N4. We also emphasize the safety characteristics of Si3N4 for mammalian cells. Contact between the virions and micrometric Si3N4 particles immediately targeted a variety of viral molecules by inducing post-translational oxidative modifications of S-containing amino acids, nitration of the tyrosine residue in the spike receptor binding domain, and oxidation of RNA purines to form formamidopyrimidine. This structural damage in turn led to a reshuffling of the protein secondary structure. These clear fingerprints of viral structure modifications were linked to inhibition of viral functionality and infectivity. This study validates the notion that Si3N4 bioceramic is a safe and effective antiviral compound; and a primary antiviral candidate to replace the toxic and allergenic compounds presently used in contact with the human body and in long-term environmental sanitation.
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The occurrence of the second peak (SP) on the dc magnetization curves of iron pnictide and chalcogenide single crystals (the 'fishtail' effect) has been interpreted in surprisingly different ways, ...involving, for example, a thermally induced square-to-rhombic vortex lattice transition, a crossover between single vortex pinning in the low magnetic field range and pinning of interacting vortices at higher fields, or has been treated similarly to the peak effect close to the upper critical magnetic field. Here we show that the SP in FeSe1−xTex single crystals is related to the well documented order-disorder transition in the vortex system, and its evolution in the low-temperature T domain is described by a dynamic energy balance relation. The main argument supporting this approach is the observed strong increase of the field for the onset of the SP with decreasing T down to 2 K, with an inflection-like point located between 3 and 4 K, in agreement with the two-band superconductivity reported for FeSe1−xTex.
Abstract
At J-PARC MLF, MUSE provides the world-highest flux of pulsed muon beams. U-Line, one of the four beamlines in the facility, features an intense surface muon beam from Super-Omega and ...Ultra-slow muon generated by laser ionization of thermal muonium in vacuo. The Ultra-slow muon beam is characterized by variable energy from sub-keV to tens of keV and a time resolution of several tens of times better than that of ordinary pulsed beams. These features enable the study of interesting phenomena localized at surfaces and near interfaces and fast dynamics that cannot be observed with ordinary pulsed beams. Commissioning of the beamline and instruments is underway in preparation for the start of user programs. This paper presents an overview of the facility, its current status, and its prospects.
Phosphorus (P) is a finite, non-renewable, and natural resource and a vital major nutrient for plant metabolic and developmental processes. However, adverse soil biogeochemical characteristics of ...alkaline-calcareous soils (especially Aridisols) and highly weathered acid soils (i.e., Ultisols and Oxisols) render orthophosphate (Pi) as the least available major nutrient due to P complexation, sorption, and/or fixation. In such soil environments, plant bioavailable P is only a small fraction of total soil P, seriously limiting crop growth and production. Different plant species, and even cultivars of the same species, may display a suite of growth responses that enable them to solubilize and scavenge soil P either by enhancing external Pi acquisition or reprioritizing internal Pi use under P-stress soil environments. This paper reports relative growth responses, P acquisition and P-use efficiency characteristics by 14 cultivars of spring wheat (Triticum aestivum L.) grown in solution culture with high/low P supply induced by applying soluble NH
4
H
2
PO
4
, sparingly soluble rock phosphate, and Ca
3
(PO
4
)
2
. The wheat cultivars exhibited considerable genetic diversity in biomass accumulation, P concentrations, P contents, factor (PSF) and P efficiency characteristics i.e., P utilization efficiency (PUE), P efficiency (PE), and PE ratio (PER). Plant growth and PE parameters were significantly correlated, while P uptake was linearly related with biomass increase and solution pH decrease. The wheat cultivars with high PUE, PER and P uptake, and low PSF, and plant P concentration were more efficient in utilizing P and, hence, more tolerant under P-stress environment. Biomass and P contents of "P efficient/low-P tolerant" wheat cultivars were superior to "P inefficient/low-P sensitive" cultivars at all P-stress levels. Hence, "P efficient/low-P tolerant" cultivars are the most desirable wheat genotypes for P-stress environments because they are able to scavenge more P from sparingly soluble P sources or soil-bound P forms.
The occurrence ratio of intracloud (IC) to cloud‐to‐ground (CG) discharges, which is denoted by Z‐ratio, is the crucial parameter for the studies on the global electric circuit. However, the ...latitudinal and regional dependences of Z‐ratio are not fully clarified. Therefore, using optical data obtained by the Global Lightning and Sprite Measurements on Japanese Experiment Module (JEM‐GLIMS), we distinguished the lightning discharge type, that is, IC, positive CG (+CG), and negative CG (−CG) discharges, and statistically estimated the Z‐ratio. We analyzed 8,354 lightning events that obtained by JEM‐GLIMS observation and succeeded in identifying 4,431 IC discharges, 597 +CG discharges, and 3,326 −CG discharges. From this result, we calculated the Z‐ratio over many regions around the world and estimated its latitudinal and regional dependences. It is found that the Z‐ratio over the continental area is larger than the oceanic area. We also found that the Z‐ratio significantly decreases with the latitude, which is generally comparable to the results shown in the previous studies. The estimated Z‐ratio varies from 2.9–0.29 from the equator to 50° latitude, and the global mean value is 1.6. The regional dependence of Z‐ratio derived from this study can be combined with the CG lightning data provided by the ground‐based lightning detection networks to estimate the occurrence number of IC discharges. Then, the occurrence number of both IC and CG discharges can be used for calculating a more accurate estimation of the total lightning currents in the global electric circuit.
Key Points
A new method for classifying the lightning discharge type has been developed using JEM‐GLIMS and the ground‐based lightning data
Lightning flashes obtained by JEM‐GLIMS observation were used to study the geographic distribution of Z‐ratio
The relationship between Z‐ratio and latitude was found, in which it has a good agreement compared with previous studies
Abstract Background We have previously reported a hybrid procedure that uses a combination of laparoscopic mobilization of the liver and subsequent hepatectomy under direct vision in living donor ...liver transplantation (LDLT). We present the details of this hybrid procedure and the outcomes of the procedure. Methods Between January 1997 and August 2014, 204 LDLTs were performed at Nagasaki University Hospital. Among them, 67 recent donors underwent hybrid donor hepatectomy. Forty-one donors underwent left hemihepatectomy, 25 underwent right hemihepatectomy, and 1 underwent posterior sectionectomy. First, an 8-cm subxiphoid midline incision was made; laparoscopic mobilization of the liver was then achieved with a hand-assist through the midline incision under the pneumoperitoneum. Thereafter, the incision was extended up to 12 cm for the right lobe and posterior sector graft and 10 cm left lobe graft procurement. Under direct vision, parenchymal transection was performed by means of the liver-hanging maneuver. The hybrid procedure for LDLT recipients was indicated only for selected cases with atrophic liver cirrhosis without a history of upper abdominal surgery, significant retroperitoneal collateral vessels, or hypertrophic change of the liver (n = 29). For total hepatectomy and splenectomy, the midline incision was sufficiently extended. Results All of the hybrid donor hepatectomies were completed without an extra subcostal incision. No significant differences were observed in the blood loss or length of the operation compared with conventional open procedures. All of the donors have returned to their preoperative activity level, with fewer wound-related complaints compared with those treated with the use of the conventional open procedure. In recipients treated with the hybrid procedure, no clinically relevant drawbacks were observed compared with the recipients treated with a regular Mercedes-Benz–type incision. Conclusions Our hybrid procedure was safely conducted with the same quality as the conventional open procedure in both LDLT donors and recipients.
Bone structure and function are maintained by well-regulated bone metabolism and remodeling. Although the underlying molecular and cellular mechanisms are now being understood, physiological and ...pathological states of bone are still difficult to predict due to the complexity of intercellular signaling. We have now developed a novel in silico experimental platform, V-Bone, to integratively explore bone remodeling by linking complex microscopic molecular/cellular interactions to macroscopic tissue/organ adaptations. Mechano-biochemical couplings modeled in V-Bone relate bone adaptation to mechanical loading and reproduce metabolic bone diseases such as osteoporosis and osteopetrosis. V-Bone also enables in silico perturbation on a specific signaling molecule to observe bone metabolic dynamics over time. We also demonstrate that this platform provides a powerful way to predict in silico therapeutic effects of drugs against metabolic bone diseases. We anticipate that these in silico experiments will substantially accelerate research into bone metabolism and remodeling.
Betalains are synthesized in flowers, fruits and other tissues of the plant order Caryophyllales. Betalamic acid is the chromophore of betalain pigments synthesized by a ring-cleaving enzyme reaction ...on l-dihydroxyphenylalanine (DOPA). Although reverse genetic evidence has proven that DOPA 4,5-dioxygenase (DOD) is a key enzyme of betalain biosynthesis, all attempts to detect recombinant plant DOD activity in vitro have failed. Here, we report on the formation of betalamic acid from DOPA under suitable assay conditions using recombinant MjDOD produced by Escherichia coli. This is the first report showing biochemical evidence for DOD activity in vitro.
The elastic behavior of aluminum alloy foam under uniaxial loading and bending conditions is studied by experimental investigations and theoretical analyses. It is found from the experiments that the ...elastic moduli measured from three- and four-point bending tests as well as flexural vibration tests are significantly larger than the corresponding elastic moduli measured from uniaxial compression tests. This discrepancy cannot be described by the well-known elastic modulus equation introduced by Gibson and Ashby for foam materials. Theoretical analyses are carried out to explain the discrepancy and to improve the elastic modulus equation of Gibson and Ashby. In the analyses, unit-cell models are proposed, and elastic modulus equations for both uniaxial loading and bending conditions are derived. The derived equations offer a good description of the discrepancy as well as reveal the prominent role of cell local deformation under bending condition. Furthermore, the present work offers clear evidence that the classical continuum theories, such as Bernoulli–Euler beam theory, are inadequate for describing the elastic bending behavior of metal foams.
No direct observational evidence of sprite‐produced active radicals has been presented owing to the difficulty of observing a small event area in the nighttime mesosphere, whereas sprite chemical ...models have indicated that sprite discharge locally affects the atmospheric composition. We present the first observational evidence of a HO2 production above sprite‐producing thunderstorms from the coincidence of temporal‐spatial observations of HO2 spectra, sprite events, and thunderstorms by two space instruments, a submillimeter‐wave limb spectrometer and ultraviolet/visible Imager and a ground‐based very low frequency radiation lightning detection network. A total of three areas was identified with enhanced HO2 levels of approximately 1025 molecules. A chemical sprite model indicates an increase in HO2 in the considered altitude region; however, the predicted production due to a single sprite event is smaller than the observed enhancement. Our observational results suggest that sprites potentially contribute 1% of nighttime background HO2 generation at altitudes of 75–80 km globally.
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