The discovery of the Higgs boson at the LHC exposes some of the most profound mysteries fundamental physics has encountered in decades, opening the door to the next phase of experimental exploration. ...More than ever, this will necessitate new machines to push us deeper into the energy frontier. In this article, we discuss the physics motivation and present the physics potential of a proton–proton collider running at an energy significantly beyond that of the LHC and a luminosity comparable to that of the LHC. 100 TeV is used as a benchmark of the center of mass energy, with integrated luminosities of 3ab−1–30ab−1.
A
bstract
The QCD axion’s coupling to photons is often assumed to lie in a narrow band as a function of the axion mass. We demonstrate that several simple mechanisms, in addition to the photophilic ...clockwork axion already in the literature, can significantly extend the allowed range of couplings. Some mechanisms we present generalize the KNP alignment scenario, widely studied as a model of inflation, to the phenomenology of a QCD axion. In particular we present KSVZ-like realizations of two-axion KNP alignment and of the clockwork mechanism. Such a “confinement tower” realization of clockwork may prove useful in a variety of model-building contexts. We also show that kinetic mixing of the QCD axion with a lighter axion-like particle can dramatically alter the QCD axion’s coupling to photons, differing from the other models we present by allowing non-quantized couplings. The simple models that we present fully cover the range of axion-photon couplings that could be probed by experiments. They motivate growing axion detection efforts over a wide space of masses and couplings.
The Chinese government launched the Air Pollution Prevention and
Control Action Plan in 2013, and various stringent measures have since been
implemented, which have resulted in significant decreases ...in emissions and
ambient concentrations of primary pollutants such as SO2, NOx, and
particulate matter (PM). However, surface ozone (O3) concentrations
have still been increasing in urban areas across the country. In a previous
analysis, we examined in detail the roles of meteorological variation during
2013–2017 in the summertime surface O3 trend in various regions of
China. In this study, we evaluated the effect of changes in multi-pollutant
emissions from anthropogenic activities on O3 levels during the same
period by using an up-to-date regional chemical transport model (WRF-CMAQ)
driven by an interannual anthropogenic emission inventory. The Community Multiscale Air
Quality (CMAQ) model
was improved with regard to heterogeneous reactions of reactive gases on
aerosol surfaces, which led to better model performance in reproducing the
ambient concentrations of those gases. The model simulations showed that the
maximum daily 8 h average (MDA8) O3 mixing ratio in urban areas
increased by 0.46 ppbv per year (ppbv a−1) (p=0.001) from 2013 to
2017. In contrast, a slight decrease in MDA8 O3 by 0.17 ppbv a−1
(p=0.005) in rural areas was predicted, mainly attributable to the
NOx emission reduction. The effects of changes in individual pollutant
emissions on O3 were also simulated. The reduction of NOx emission
increased the O3 levels in urban areas due to the nonlinear
NOx and volatile organic compound (VOC) chemistry and decreasing aerosol
effects; the slight increase in VOC emissions enhanced the O3 levels;
the reduction of PM emissions increased the O3 levels by enhancing the
photolysis rates and reducing the loss of reactive gases on aerosol
surfaces; and the reduction of SO2 emissions resulted in a drastic
decrease in sulfate concentrations, which increased O3 through aerosol
effects. In contrast to the unfavorable effect of the above changes in
pollutant emissions on efforts to reduce surface O3, the reduction of
CO emissions did help to decrease the O3 level in recent years. The
dominant cause of increasing O3 due to changes in anthropogenic
emissions varied geographically. In Beijing, NOx and PM emission
reductions were the two largest causes of the O3 increase; in Shanghai,
the reduction of NOx and increase in VOC emissions were the two major
causes; in Guangzhou, NOx reduction was the primary cause; in
Chengdu, the PM and SO2 emission decreases contributed most to the
O3 increase. Regarding the effects of decreasing concentrations of
aerosols, the drop in heterogeneous uptake of reactive gases – mainly
HO2 and O3 – was found to be more important than the increase in
photolysis rates. The adverse effect of the reductions of NOx,
SO2, and PM emissions on O3 abatement in Beijing, Shanghai,
Guangzhou, and Chengdu would have been avoided if the anthropogenic VOCs
emission had been reduced by 24 %, 23 %, 20 %, and 16 %,
respectively, from 2013 to 2017. Our analysis revealed that the NOx
reduction in recent years has helped to contain the total O3 production
in China. However, to reduce O3 levels in major urban and industrial
areas, VOC emission controls should be added to the current
NOx-SO2-PM policy.
Liver cancer is a serious global health problem and a common cause of cancer-related death. Hepatocellular carcinoma (HCC) is a common pathological type of liver cancer. The clinical symptoms of ...early HCC tend to be not obvious and 50% of HCC patients are already in the advanced stage by the time they are diagnosed. Systemic therapy is recommended for the treatment of advanced HCC. With the development of molecular targeted drugs (sorafenib and lenvatinib), some progress has been made in the systemic treatment of advanced HCC, but there is only modest benefit for the survival of HCC patients. In recent years, the emergence of immune checkpoint inhibitors has changed the overall outlook of HCC treatment, providing more possibilities for precise treatment of HCC and showing better treatment outcomes. In particular, the combination therapy of atezolizumab and bevacizumab significantly improved the survival outcomes in HCC patients. In addition, adoptive cell therapy, tumor vaccine, oncolytic viruses, and nonspec
Three-dimensional topological Weyl semimetals can generally support a zero-dimensional Weyl point characterized by a quantized Chern number or a one-dimensional Weyl nodal ring characterized by a ...quantized Berry phase in the momentum space. Here, in a dissipative system with particle gain and loss, we discover a new type of topological ring, dubbed a Weyl exceptional ring consisting of exceptional points at which two eigenstates coalesce. Such a Weyl exceptional ring is characterized by both a quantized Chern number and a quantized Berry phase, which are defined via the Riemann surface. We propose an experimental scheme to realize and measure the Weyl exceptional ring in a dissipative cold atomic gas trapped in an optical lattice.
We explore the physics potential of using precision timing information at the LHC in searches for long-lived particles (LLPs). In comparison with the light standard model particles, the decay ...products of massive LLPs arrive at detectors with time delays around the nanosecond scale. We propose new strategies to take advantage of this time delay feature by using initial state radiation to time stamp the collision event and require at least one LLP to decay within the detector. This search strategy is effective for a broad range of models. In addition to outlining this general approach, we demonstrate its effectiveness with the projected reach for two benchmark scenarios: a Higgs boson decaying into a pair of LLPs, and pair production of long-lived neutralinos in the gauge mediated supersymmetry breaking models. Our strategy increases the sensitivity to the lifetime of the LLP by two orders of magnitude or more and particularly exhibits a better behavior with a linear dependence on the lifetime in the large lifetime region compared to traditional LLP searches. The timing information significantly reduces the standard model background and provides a powerful new dimension for LLP searches.
Abiotic stress severely influences plant growth and development. MYB transcription factors (TFs), which compose one of the largest TF families, play an important role in abiotic stress responses.
We ...identified 139 soybean MYB-related genes; these genes were divided into six groups based on their conserved domain and were distributed among 20 chromosomes (Chrs). Quantitative real-time PCR (qRT-PCR) indicated that GmMYB118 highly responsive to drought, salt and high temperature stress; thus, this gene was selected for further analysis. Subcellular localization revealed that the GmMYB118 protein located in the nucleus. Ectopic expression (EX) of GmMYB118 increased tolerance to drought and salt stress and regulated the expression of several stress-associated genes in transgenic Arabidopsis plants. Similarly, GmMYB118-overexpressing (OE) soybean plants generated via Agrobacterium rhizogenes (A. rhizogenes)-mediated transformation of the hairy roots showed improved drought and salt tolerance. Furthermore, compared with the control (CK) plants, the clustered, regularly interspaced, short palindromic repeat (CRISPR)-transformed plants exhibited reduced drought and salt tolerance. The contents of proline and chlorophyll in the OE plants were significantly greater than those in the CK plants, whose contents were greater than those in the CRISPR plants under drought and salt stress conditions. In contrast, the reactive oxygen species (ROS) and malondialdehyde (MDA) contents were significantly lower in the OE plants than in the CK plants, whose contents were lower than those in the CRISPR plants under stress conditions.
These results indicated that GmMYB118 could improve tolerance to drought and salt stress by promoting expression of stress-associated genes and regulating osmotic and oxidizing substances to maintain cell homeostasis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A highly sensitive optical fiber surface plasmon resonance (SPR) biosensor based on graphene oxide (GO) and staphylococcal protein A (SPA) co-modified tilted fiber Bragg grating (TFBG) is proposed ...and demonstrated for the detection of human immunoglobulin G (IgG) for the first time. The gold film on the surface of the sensor was first fixed with GO and then modified with an SPA to improve the sensitivity of the sensor. Large specific surface area and abundant functional groups of GO can adsorb more antibodies. The combination of SPA and the antibody molecule Fc region makes the Fab area with antigen-binding sites extend outward, resulting in highly oriented antibody immobilization on the sensor surface and high antigen-antibody binding efficiency. The experimental results show that the sensitivity as well as the limit of detection of GO-SPA-modified TFBG-SPR biosensor is around 0.096 dB/(<inline-formula> <tex-math notation="LaTeX">\mu \text{g} </tex-math></inline-formula>/mL) and <inline-formula> <tex-math notation="LaTeX">0.5~\mu \text{g} </tex-math></inline-formula>/mL, showing better responses to human IgG solutions with a concentration range of 30-<inline-formula> <tex-math notation="LaTeX">100~\mu \text{g} </tex-math></inline-formula>/mL compared with the TFBG-SPR biosensors modified singly with GO or SPA. The biosensor exhibits the advantages of small size, ease of fabrication, high sensitivity, label-free, and rapid response, and provides a new solution for detecting low concentration of biological solution, presenting great application potential in the biochemistry field.
Summary
Plant microbiomes are essential to host health and productivity but the ecological processes that govern crop microbiome assembly are not fully known.
Here we examined bacterial communities ...across 684 samples from soils (rhizosphere and bulk soil) and multiple compartment niches (rhizoplane, root endosphere, phylloplane, and leaf endosphere) in maize (Zea mays)‐wheat (Triticum aestivum)/barley (Hordeum vulgare) rotation system under different fertilization practices at two contrasting sites.
Our results demonstrate that microbiome assembly along the soil‐plant continuum is shaped predominantly by compartment niche and host species rather than by site or fertilization practice. From soils to epiphytes to endophytes, host selection pressure sequentially increased and bacterial diversity and network complexity consequently reduced, with the strongest host effect in leaf endosphere. Source tracking indicates that crop microbiome is mainly derived from soils and gradually enriched and filtered at different plant compartment niches. Moreover, crop microbiomes were dominated by a few dominant taxa (c. 0.5% of bacterial phylotypes), with bacilli identified as the important biomarker taxa for wheat and barley and Methylobacteriaceae for maize.
Our work provides comprehensive empirical evidence on host selection, potential sources and enrichment processes for crop microbiome assembly, and has important implications for future crop management and manipulation of crop microbiome for sustainable agriculture.
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