We numerically study the thermoelectric transport properties in bilayer phosphorene in the presence of bias voltage under a strong magnetic field. When a bias voltage is applied and the bulk energy ...gap is closed, it is found that thermoelectric coefficients has similar properties to those of a semimetal. Around the central Landau Level (LL), the transverse thermoelectric conductivity displays a series of peaks, but the longitudinal thermoelectric conductivity oscillates and changes sign. The Nernst signal has a peak at central LL and changes sign near other LLs, while the thermopower has an opposite behavior. Both the thermoelectric conductivities and Nernst signal exhibit remarkable anisotropy, but thermopower exhibits isotropy.
Abstract
Magnetic reconnection, a fundamental plasma process transforming magnetic field energy into particle energy, is ubiquitous in space and responsible for many explosive phenomena, such as ...solar flares and gamma-ray bursts. Recent numerical theories have predicted that reconnection fronts far from the primary reconnection region can host secondary reconnection in three-dimensional scenarios, different from the conventional two-dimensional diagram where only one X-line stands to sustain reconnection. In this study, we provide direct observational evidence for ongoing secondary reconnection in the reconnection front via the unprecedentedly high-cadence data from NASA’s MMS mission. The secondary reconnection is identified by the presence of an X-line, a super-Alfvénic electron jet, and nonideal energy dissipation. Different from the primary ion–electron reconnection, the secondary reconnection is electron-only, with its X-line quasi-perpendicular to the primary X-line. Hence reconnection, when evolving from local to global scales, becomes essentially three-dimensional with different patterns developed. These results provide crucial insights into understanding cross-scale energy transport driven by reconnection in space plasmas.
Determining the best therapy for HIV-associated cryptococcal meningitis in resource-poor settings is controversial. In this trial in Vietnam, initial therapy with amphotericin B with flucytosine had ...better outcomes than amphotericin B alone or with fluconazole.
There are approximately 1 million cases of cryptococcal meningitis annually and 625,000 deaths.
1
Treatment guidelines recommend induction therapy with amphotericin B deoxycholate (0.7 to 1 mg per kilogram of body weight per day) and flucytosine (100 mg per kilogram per day).
2
However, this treatment has not been shown to reduce mortality, as compared with amphotericin B monotherapy.
2
,
3
Flucytosine is frequently unavailable where the disease burden is greatest, and concerns about cost and side effects have limited its use in resource-poor settings.
4
Fluconazole is readily available, is associated with low rates of adverse events, and has good penetration into cerebrospinal . . .
Specialized adult somatic cells, such as cardiomyocytes (CMs), are highly differentiated with poor renewal capacity, an integral reason underlying organ failure in disease and aging. Among the least ...renewable cells in the human body, CMs renew approximately 1% annually. Consistent with poor CM turnover, heart failure is the leading cause of death. Here, we show that an active version of the Hippo pathway effector YAP, termed YAP5SA, partially reprograms adult mouse CMs to a more fetal and proliferative state. One week after induction, 19% of CMs that enter S-phase do so twice, CM number increases by 40%, and YAP5SA lineage CMs couple to pre-existing CMs. Genomic studies showed that YAP5SA increases chromatin accessibility and expression of fetal genes, partially reprogramming long-lived somatic cells in vivo to a primitive, fetal-like, and proliferative state.
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•Creation of a mouse conditionally expressing active YAP called YAP5SA•YAP5SA in adult cardiomyocytes (CMs) induces a more primitive transcriptional state•YAP5SA activates developmental enhancers•YAP5SA expression in CMs causes CM hyperplasia and overall heart hypercellularity
As highly differentiated cells, cardiomyocytes have poor renewal capacity, a contributing factor to heart failure in aging and disease. Monroe et al. created a mouse conditionally overexpressing active YAP (YAP5SA) and show that YAP5SA expression induces adult cardiomyocytes to adopt a more proliferative state with fetal-like chromatin and transcriptional landscapes.
Challenges in semileptonic B decays Gambino, P.; Kronfeld, A. S.; Rotondo, M. ...
The European physical journal. C, Particles and fields,
10/2020, Letnik:
80, Številka:
10
Journal Article
Recenzirano
Odprti dostop
Two of the elements of the Cabibbo–Kobayashi–Maskawa quark mixing matrix,
|
V
ub
|
and
|
V
cb
|
, are extracted from semileptonic
B
decays. The results of the
B
factories, analysed in the light of ...the most recent theoretical calculations, remain puzzling, because for both
|
V
ub
|
and
|
V
cb
|
the exclusive and inclusive determinations are in clear tension. Further, measurements in the
τ
channels at Belle, Babar, and LHCb show discrepancies with the Standard Model predictions, pointing to a possible violation of lepton flavor universality. LHCb and Belle II have the potential to resolve these issues in the next few years. This article summarizes the discussions and results obtained at the MITP workshop held on April 9–13, 2018, in Mainz, Germany, with the goal to develop a medium-term strategy of analyses and calculations aimed at solving the puzzles. Lattice and continuum theorists working together with experimentalists have discussed how to reshape the semileptonic analyses in view of the much higher luminosity expected at Belle II, searching for ways to systematically validate the theoretical predictions in both exclusive and inclusive
B
decays, and to exploit the rich possibilities at LHCb.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Recent observations strongly suggest that the millisecond pulsar binary PSR J1023+0038 has developed an accretion disk since 2013 June. We present a multi-wavelength analysis of PSR J1023+0038, which ...reveals that (1) its gamma-rays suddenly brightened within a few days in 2013 June/July and has remained at a high gamma-ray state for several months; (2) both UV and X-ray fluxes have increased by roughly an order of magnitude; and (3) the spectral energy distribution has changed significantly after the gamma-ray sudden flux change. Time variabilities associated with UV and X-rays are on the order of 100-500 s and 50-100 s, respectively. Our model suggests that a newly formed accretion disk, due to the sudden increase of the stellar wind, could explain the changes of all these observed features. The increase of UV is emitted from the disk, and a new component in gamma-rays is produced by inverse Compton scattering between the new UV component and pulsar wind. The increase of X-rays results from the enhancement of injection pulsar wind energy into the intra-binary shock due to the increase of the stellar wind. We also predict that the radio pulses may be blocked by the evaporated winds from the disk, and the pulsar is still powered by rotation.
Abstract
Background
Plasmodium falciparum and Plasmodium vivax account for >90% global malaria burden. Transmission intervention strategies encompassing transmission-blocking vaccines (TBV) and drugs ...represent ideal public health tools to eliminate malaria at the population level. The availability of mature P. falciparum gametocytes through in vitro culture has facilitated development of a standard membrane feeding assay to assess efficacy of transmission interventions against P. falciparum. The lack of in vitro culture for P. vivax has significantly hampered similar progress on P. vivax and limited studies have been possible using blood from infected patients in endemic areas. The ethical and logistical limitations of on-time access to blood from patients have impeded the development of P. vivax TBVs.
Methods
Transgenic murine malaria parasites (Plasmodium berghei) expressing TBV candidates offer a promising alternative for evaluation of P. vivax TBVs through in vivo studies in mice, and ex vivo membrane feeding assay (MFA).
Results
We describe the development of transmission-competent transgenic TgPbvs25 parasites and optimization of parameters to establish an ex vivo MFA to evaluate P. vivax TBV based on Pvs25 antigen.
Conclusions
The MFA is expected to expedite Pvs25-based TBV development without dependence on blood from P. vivax-infected patients in endemic areas for evaluation.
Summary
The possibility to predict the outcome of targeted DNA double‐stranded break (DSB) repair would be desirable for genome editing. Furthermore the consequences of mis‐repair of potentially ...cell‐lethal DSBs and the underlying pathways are not yet fully understood. Here we study the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9‐induced mutation spectra at three selected endogenous loci in Arabidopsis thaliana by deep sequencing of long amplicon libraries. Notably, we found sequence‐dependent genomic features that affected the DNA repair outcome. Deletions of 1‐bp to <1000‐bp size and/or very short insertions, deletions >1 kbp (all due to NHEJ) and deletions combined with insertions between 5‐bp to >100 bp caused by a synthesis‐dependent strand annealing (SDSA)‐like mechanism occurred most frequently at all three loci. The appearance of single‐stranded annealing events depends on the presence and distance between repeats flanking the DSB. The frequency and size of insertions is increased if a sequence with high similarity to the target site was available in cis. Most deletions were linked to pre‐existing microhomology. Deletion and/or insertion mutations were blunt‐end ligated or via de novo generated microhomology. While most mutation types and, to some degree, their predictability are comparable with animal systems, the broad range of deletion mutations seems to be a peculiar feature of the plant A. thaliana.
Significance Statement
Little information is known of what effect the target sequence has on the result of genome editing. We found that the choice of repair pathways and the outcome regarding size and frequency of deletions and insertions at targeted double‐stranded breaks depends on the sequence context (e.g. the presence and arrangement of repeats), thus having the potential to predict the results of genome editing in Arabidopsis thaliana.
Antibiotic resistance is a critical global health care crisis requiring urgent action to develop more effective antibiotics. Utilizing the hydrophobic scaffold of xanthone, we identified three ...components that mimicked the action of an antimicrobial cationic peptide to produce membrane-targeting antimicrobials. Compounds 5c and 6, which contain a hydrophobic xanthone core, lipophilic chains, and cationic amino acids, displayed very promising antimicrobial activity against multidrug-resistant Gram-positive bacteria, including MRSA and VRE, rapid time–kill, avoidance of antibiotic resistance, and low toxicity. The bacterial membrane selectivity of these molecules was comparable to that of several membrane-targeting antibiotics in clinical trials. 5c and 6 were effective in a mouse model of corneal infection by S. aureus and MRSA. Evidence is presented indicating that 5c and 6 target the negatively charged bacterial membrane via a combination of electrostatic and hydrophobic interactions. These results suggest that 5c and 6 have significant promise for combating life-threatening infections.
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