1,159 research outputs found
Characterization of a wheat HSP70 gene and its expression in response to stripe rust infection and abiotic stresses
Members of the family of 70-kD heat shock proteins (HSP70 s) play various stress-protective roles in plants. In this study, a wheat HSP70 gene was isolated from a suppression subtractive hybridization (SSH) cDNA library of wheat leaves infected by Puccinia striiformis f. sp. tritici. The gene, that was designated as TaHSC70, was predicted to encode a protein of 690 amino acids, with a molecular mass of 73.54 KDa and a pI of 5.01. Further analysis revealed the presence of a conserved signature that is characteristic for HSP70s and phylogenetic analysis demonstrated that TaHSC70 is a homolog of chloroplast HSP70s. TaHSC70 mRNA was present in leaves of both green and etiolated wheat seedlings and in stems and roots. The transcript level in roots was approximately threefold less than in leaves but lightâdark treatment did not charge TaHSC70 expression. Following heat shock of wheat seedlings at 40°C, TaHSC70 expression increased in leaves of etiolated seedlings but remained stable at the same level in green seedlings. In addition, TaHSC70 was differentially expressed during an incompatible and compatible interaction with wheat-stripe rust, and there was a transient increase in expression upon treatment with methyl jasmonate (MeJA) treatment. Salicylic acid (SA), ethylene (ET) and abscisic acid (ABA) treatments had no influence on TaHSC70 expression. These results suggest that TaHSC70 plays a role in stress-related responses, and in defense responses elicited by infection with stripe rust fungus and does so via a JA-dependent signal transduction pathway
Photoplethysmography-Based Machine Learning Approaches for Atrial Fibrillation Prediction:A Report From the Huawei Heart Study
BACKGROUND: Current wearable devices enable the detection of atrial fibrillation (AF), but a machine learning (ML)âbased approach may facilitate accurate prediction of AF onset. OBJECTIVES: The present study aimed to develop, optimize, and validate an ML-based model for real-time prediction of AF onset in a population at high risk of incident AF. METHODS: A primary ML-based prediction model of AF onset (M1) was developed on the basis of the Huawei Heart Study, a general-population AF screening study using photoplethysmography (PPG)âbased smart devices. After optimization in 554 individuals with 469,267 PPG data sets, the optimized ML-based model (M2) was further prospectively validated in 50 individuals with paroxysmal AF at high risk of AF onset, and compared with 72-hour Holter electrocardiographic (ECG) monitoring, a criterion standard, from September 1, 2019, to November 5, 2019. RESULTS: Among 50 patients with paroxysmal AF (mean age 67 ± 12 years, 40% women), there were 2,808 AF events from a total of 14,847,356 ECGs over 72 hours and 6,860 PPGs (45.83 ± 13.9 per subject per day). The best performance of M1 for AF onset prediction was achieved 4 hours before AF onset (area under the receiver operating characteristic curve: 0.94; 95% confidence interval: 0.93-0.94). M2 sensitivity, specificity, positive predictive value, negative predictive value, and accuracy (at 0 to 4 hours before AF onset) were 81.9%, 96.6%, 96.4%, 83.1%, and 88.9%, respectively, compared with 72-hour Holter ECG. CONCLUSIONS: The PPG- based ML model demonstrated good ability for AF prediction in advance. (Mobile Health [mHealth] technology for improved screening, patient involvement and optimizing integrated care in atrial fibrillation; ChiCTR-OOC-17014138
Two qubits of a W state violate Bell's inequality beyond Cirel'son's bound
It is shown that the correlations between two qubits selected from a trio
prepared in a W state violate the Clauser-Horne-Shimony-Holt inequality more
than the correlations between two qubits in any quantum state. Such a violation
beyond Cirel'son's bound is smaller than the one achieved by two qubits
selected from a trio in a Greenberger-Horne-Zeilinger state [A. Cabello, Phys.
Rev. Lett. 88, 060403 (2002)]. However, it has the advantage that all local
observers can know from their own measurements whether their qubits belongs or
not to the selected pair.Comment: REVTeX4, 5 page
Probing the nature of the conjectured low-spin wobbling bands in atomic nuclei
The precession of an atomic nucleus can be approximately described as wobbling motion, arising from the coupling of a rotation and a harmonic vibration. Recently, a number of wobbling bands were reported at low spin, which violate the wobbling approximation that can be valid only at high spin. In the present work, we explore the nature of the reported low-spin wobbling bands. Via a new experiment including both angular correlation and linear polarization measurements, we demonstrate that one such band in 187Au is generated by dominant single-particle excitation rather than by the excitation of a wobbling phonon. Assessing the experimental proofs and discussions to assign the reported low-spin wobbling bands, we further point out that the imperfect research paradigm used previously would lead to unreliable identification of low-spin wobbling bands
Iron isotope compositions of coexisting sulfide and silicate minerals in Sudbury-type ores from the Jinchuan Ni-Cu- sulfide deposit: A perspective on possible core-mantle iron isotope fractionation
Many studies have shown that the average iron (Fe) isotope compositions of mantle-derived rocks, mantle peridotite and model mantle are close to those of chondrites. Therefore, it is considered that chondrite values represent the bulk Earth Fe isotope composition. However, this is a brave assumption because nearly 90% Fe of the earth is in the core, whose Fe isotope composition is unknown, but is required to construct bulk earth Fe isotope composition. We approach the problem by assuming that the earthâs core separation can be approximated in terms of the Sudbury-type Ni-Cu sulfide mineralization, where sulfide-saturated mafic magmas segregate into immiscible sulfide liquid and silicate liquid. Their density/buoyancy controlled stratification and solidification produced net-textured ores above massive ores and below disseminated ores. The coexisting sulfide minerals (pyrrhotite (Po) > pentlandite (Pn) > chalcopyrite (Cp)) and silicate minerals (olivine (Ol) > orthopyroxene (Opx) > clinopyroxene (Cpx)) are expected to hold messages on Fe isotope fractionation between the two liquids before their solidification. We studied the net-textured ores of the Sudbury-type Jinchuan Ni-Cu sulfide deposit. The sulfide minerals show varying ÎŽ56Fe values (-1.37 ~ -0.74â° (Po) < 0.09 ~ 0.56â° (Cp) < 0.53 ~ 1.05â° (Pn), but silicate minerals (Ol, Opx, Cpx) have ÎŽ56Fe values close to chondrites (ÎŽ56Fe = -0.01±0.01â°). The heavy ÎŽ56Fe value (0.52 ~ 0.60â°) of serpentines may reflect Fe isotopes exchange with the coexisting pyrrhotite with light ÎŽ56Fe. We ob- tained an equilibrium fractionation factor of Î56Fesilicate-sulfide = ~ 0.51â° between reconstructed silicate liquid (ÎŽ56Fe = ~ 0.21â°) and sulfide liquid (ÎŽ56Fe = ~ -0.30â°), or Î56Fesilicate-sulfide = ~ 0.36â° between the weighted mean bulk-silicate minerals (ÎŽ56Fe[0.70ol,0.25opx,0.05cpx] = 0.06â°) with weighted mean bulk- sulfide minerals (ÎŽ56Fe = ~ -0.30â°). Our study indicates that significant Fe isotope fractionation does take place between silicate and sulfide liquids during the Sudbury-type sulfide mineralization. We hypothesize that significant iron isotope fractionation must have taken place during core-mantle segregation, and the bulk earth may have lighter Fe isotope composition than chondrites although Fe isotope analysis on experimental sulfide-silicate liquids produced under the varying mantle depth conditions is needed to test our results. We advocate the importance of further research on the subject. Given the close Fe-Ni association in the magmatic mineralization and the majority of Earthâs Ni is also in the core, we infer that Ni isotope fractionation must also have taken place during the core separation that needs attention
Stroke Prevention in Atrial Fibrillation:A Scientific Statement of JACC: Asia (Part 2)
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with substantial increases in the risk for stroke and systemic thromboembolism. With the successful introduction of the first non-vitamin K antagonistdirect oral anticoagulant agent (NOAC) in 2009, the role of vitamin K antagonists has been replaced in most clinical settings except in a few conditions for which NOACs are contraindicated. Data for the use of NOACs in different clinical scenarios have been accumulating in the past decade, and a more sophisticated strategy for patients with AF is now warranted. JACC: Asia recently appointed a working group to summarize the most updated information regarding stroke prevention in AF. The aim of this statement is to provide possible treatment options in daily practice. Local availability, cost, and patient comorbidities should also be considered. Final decisions may still need to be individualized and based on cliniciansâ discretion. This is part 2 of the statement
Stroke Prevention in Atrial Fibrillation:A Scientific Statement of JACC: Asia (Part 1)
Atrial fibrillation is the most common sustained cardiac arrhythmia and is associated with substantial increases in the risk of stroke and systemic thromboembolism. With the successful introduction of the first non-vitamin K antagonist direct oral anticoagulant (NOAC) in 2009, the role of vitamin K antagonists has been replaced in most clinical settings except in a few conditions when NOACs are contraindicated. Data for the use of NOACs in different clinical scenarios have been accumulating in the recent decade, and a more sophisticated strategy for atrial fibrillation patients is now warranted. JACC: Asia recently appointed a working group to summarize the most updated information regarding stroke prevention in AF. This statement aimed to provide possible treatment option in daily practice. Local availability, cost, and patient comorbidities should also be considered. Final decisions may still need to be individualized and based on cliniciansâ discretion. This is the part 1 of the whole statement
Crossing w=-1 in Gauss-Bonnet Brane World with Induced Gravity
Recent type Ia supernovas data seemingly favor a dark energy model whose
equation of state crosses -1 very recently, which is a much more amazing
problem than the acceleration of the universe. In this paper we show that it is
possible to realize such a crossing without introducing any phantom component
in a Gauss-Bonnet brane world with induced gravity, where a four dimensional
curvature scalar on the brane and a five dimensional Gauss-Bonnet term in the
bulk are present. In this realization, the Gauss-Bonnet term and the mass
parameter in the bulk play a crucial role.Comment: Revtex 16 pages including 10 eps files, references added, to appear
in Comm. Theor. Phy
Charmless Exclusive Baryonic B Decays
We present a systematical study of two-body and three-body charmless baryonic
B decays. Branching ratios for two-body modes are in general very small,
typically less than , except that \B(B^-\to p \bar\Delta^{--})\sim
1\times 10^{-6}. In general, due to
the large coupling constant for . For three-body modes we
focus on octet baryon final states. The leading three-dominated modes are with a branching ratio of
order for and
for . The penguin-dominated decays with strangeness
in the meson, e.g., and , have appreciable rates and the mass
spectrum peaks at low mass. The penguin-dominated modes containing a strange
baryon, e.g., , have
branching ratios of order . In contrast, the decay
rate of is smaller. We explain why some of
charmless three-body final states in which baryon-antibaryon pair production is
accompanied by a meson have a larger rate than their two-body counterparts:
either the pole diagrams for the former have an anti-triplet bottom baryon
intermediate state, which has a large coupling to the meson and the
nucleon, or they are dominated by the factorizable external -emission
process.Comment: 46 pages and 3 figures, to appear in Phys. Rev. D. Major changes are:
(i) Calculations of two-body baryonic B decays involving a Delta resonance
are modified, and (ii) Penguin-dominated modes B-> Sigma+N(bar)+p are
discusse
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