A Comparative Study of Z′^{\prime} mediated Charged Lepton Flavor Violation at future lepton colliders

Charged lepton flavor violation (CLFV) represents a transition between charged leptons of different generations that violates lepton flavor conservation, which is a clear signature of possible new physics beyond the standard model. By exploiting a typical example model of extra Z$^{\prime}$ gauge boson, we perform a detailed comparative study on CLFV searches at several future lepton colliders, including a 240 GeV electron-positron collider and a TeV scale muon collider. Based on detailed signal and background Monte-Carlo studies with fast detector simulations, we derive the potentials in searching for Z$^{\prime}$ mediated CLFV couplings with $e\mu$, $e\tau$ and $\mu\tau$ of different future colliders. The results are compared with the current limits set by either low-energy experiments or the high-energy LHC experiments. We find that the sensitivity of the $\tau$ related CLFV coupling strength at future lepton colliders will be significantly improved comparing with the current best constraints.Comment: 11 pages, 5 figure

Direct semi-parametric estimation of fixed effects panel data varying coefficient models.

In this paper, we present a new technique to estimate varying coefficient models of unknown form in a panel data framework where individual effects are arbitrarily correlated with the explanatory variables in an unknown way. The estimator is based on first differences and then a local linear regression is applied to estimate the unknown coefficients. To avoid a non-negligible asymptotic bias, we need to introduce a higher-dimensional kernel weight. This enables us to remove the bias at the price of enlarging the variance term and, hence, achieving a slower rate of convergence. To overcome this problem, we propose a one-step backfitting algorithm that enables the resulting estimator to achieve optimal rates of convergence for this type of problem. It also exhibits the so-called oracle efficiency property. We also obtain the asymptotic distribution. Because the estimation procedure depends on the choice of a bandwidth matrix, we also provide a method to compute this matrix empirically. The Monte Carlo results indicate the good performance of the estimator in finite samples

Nonparametric estimation of fixed effects panel data varying coefficient models.

In this paper, we consider the nonparametric estimation of a varying coefficient fixed effect panel data model. The estimator is based in a within (un-smoothed) transformation of the regression model and then a local linear regression is applied to estimate the unknown varying coefficient functions. It turns out that the standard use of this technique produces a non-negligible asymptotic bias. In order to avoid it, a high dimensional kernel weight is introduced in the estimation procedure. As a consequence, the asymptotic bias is removed but the variance is enlarged, and therefore the estimator shows a very slow rate of convergence. In order to achieve the optimal rate, we propose a one-step backfitting algorithm. The resulting two-step estimator is shown to be asymptotically normal and its rate of convergence is optimal within its class of smoothness functions. It is also oracle efficient. Further, this estimator is compared both theoretically and by Monte-Carlo simulation against other estimators that are based in a within (smoothed) transformation of the regression model. More precisely the profile least-squares estimator proposed in this context in Sun et al. (2009). It turns out that the smoothness in the transformation enlarges the bias and it makes the estimator more difficult to analyze from the statistical point of view. However, the first step estimator, as expected, shows a bad performance when compared against both the two step backfitting algorithm and the profile least-squares estimator.The authors acknowledge fi nancial support from the Programa Estatal de Fomento de la Investigación Cien ica y Técnica de Excelencia/ Spanish Ministery of Economy and Competitiveness. Ref. ECO2013-48326-C2-2-P

Impact of diurnal temperature fluctuations on larval settlement and growth of the reef coral Pocillopora damicornis

Diurnal fluctuations in seawater temperature are ubiquitous on tropical reef flats. However, the effects of such dynamic temperature variations on the early stages of corals are poorly understood. In this study, we investigated the responses of larvae and new recruits of Pocillopora damicornis to two constant temperature treatments (29 and 31 degrees C) and two diurnally fluctuating treatments (28-31 and 30-33 degrees C with daily means of 29 and 31 degrees C, respectively) simulating the 3 degrees C diel oscillations at 3m depth on the Luhuitou fringing reef (Sanya, China). Results showed that the thermal stress on settlement at 31 degrees C was almost negated by the fluctuating treatment. Further, neither elevated temperature nor temperature fluctuations caused bleaching responses in recruits, while the maximum excitation pressure over photosystem II (PSII) was reduced under fluctuating temperatures. Although early growth and development were highly stimulated at 31 degrees C, oscillations of 3 degrees C had little effects on budding and lateral growth at either mean temperature. Nevertheless, daytime encounters with the maximum temperature of 33 degrees C in fluctuating 31 degrees C elicited a notable reduction in calcification compared to constant 31 degrees C. These results underscore the complexity of the effects caused by diel temperature fluctuations on early stages of corals and suggest that ecologically relevant temperature variability could buffer warming stress on larval settlement and dampen the positive effects of increased temperatures on coral growth

Prevalence and Outcomes of Pancreatic Enzymes Elevation in Patients With COVID-19: A Meta-Analysis and Systematic Review

Background:Although coronavirus disease 2019 (COVID-19) is considered to be a disease that mainly involves the respiratory system, an increasing number of studies have reported that COVID-19 patients had pancreatic enzymes (PE) elevation and even pancreatic injury. The study aims to determine the prevalence of PE elevation, and the relationship between elevated PE and prognosis in COVID-19 patients.MethodsA comprehensive literature search was conducted according to the PRISMA guideline in PubMed, Embase, Scopus, Web of Science, and Google Scholar for studies reporting PE elevation in patients with COVID-19 from 1st January 2020 to 24th November 2021.ResultsA total of 13 studies (24,353 participants) were included in our review. The pooled prevalence of PE elevation in COVID-19 patients was 24% (18%–31%), the pooled odds ratio (OR) of mortality was 2.5 (1.7–3.6), the pooled OR of ICU admission was 4.4 (2.8–6.8), and the pooled OR of kidney injury, respiratory failure and liver injury were 3.5 (1.6–7.4), 2.0 (0.5–8.7), and 2.3 (1.4–3.9) respectively. In addition, the subgroup analysis revealed that although PE elevated to > 3 × upper normal limit (ULN) was significantly related to the mortality (OR = 4.4, 2.1–9.4), it seemed that mild elevation of PE to 1–3 ULN also had a considerable risk of mortality (OR = 2.3, 1.5–3.5).ConclusionsPE elevation was a common phenomenon in patients with COVID-19, and was associated with poor clinical outcomes. However, due to the limited numbers of included studies, the result of our study still needed to be validated.Systematic Review Registrationhttps://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=295630, identifier: CRD42021295630

Methane combustion over PdO crystallite manipulated by support template

A comparative investigation on the thermochemical and catalytic properties of palladium oxide crystallite supported on monoclinic or tetragonal-doped zirconia, demonstrated that by sharing the interfacial atoms with monoclinic zirconia, PdO crystallite aggregates at the aid of this epitaxy on the support template to acquire better dispersion. Moreover, tracking the heating-cooling cycles in air atmosphere, DTG analysis illustrated that the crystallized PdO gradually transforms into the epitaxial PdO species on the monochnic zirconia and the improved mobility of oxygen in lattices promotes the oxidative regeneration of PdO at high temperature thereby. Combining the above two superiorities on aggregation forms of NO, the template of monoclinic zirconia inhibits the high temperature deactivation of catalysts for methane combustion, meanwhile, increases the stability of combustion reaction and the sustainability of catalysts. However, the doping of tetragonal zirconia into monoclinic support muffles those advantages prominently

Identifying long-term stable refugia for dominant Castanopsis species of evergreen broad-leaved forests in East Asia: A tool for ensuring their conservation

Identifying and protecting refugia is a priority for conservation management under projected anthropogenic climate change. We have two main objectives: the first is to explore the spatial (East Asia) and temporal (Last Glacial Maximum to year 2070) distribution patterns of dominant Castanopsis species of evergreen broad-leaved forests, also the relation with their niche breadths; the second is to identify long-term stable refugia for preserving these species and provide a framework of conservation strategies. We find that there is an extraordinary richness with 32 dominant Castanopsis species, and they form both a geographically and climatically almost unbroken connection from ca. 5°N to 38°N, having thus ecological significance. During the Mid-Holocene and, particularly, the Last Glacial Maximum, the predicted suitable areas of the species as a whole were larger than those in the present. By 2070, potentially suitable areas with high richness of dominant Castanopsis species will be reduced by 94.5 % on average. No correlation between species niche breadths and distribution ranges is found, which could be due to regional climate stability. Mountains of southwestern and southern Yunnan in China are identified as climatically long-term stable refugia for 7¿9 Castanopsis species. We recommend that these refugia have the highest priority of conservation to prevent their extinction. Our suggested urgent measures include improving the effectiveness of currently protected Castanopsis species and expanding the network of protected areas to cover a larger fraction of the refugia, as well as ensuring Castanopsis species natural regeneration potential in fragmented and natural secondary forest areas.This study received financial support from the Major Program for Basic Research Project of Yunnan Province, China (202101BC070002), the Science and Technology Department of Yunnan University, China (2019YNU002), the Ministry of Science and Technology of China (2015FY210200-15), the Spanish Ministry of Science and Innovation (grant PID2020-119163GB-I00 funded by MCIN/AEI/10.13039/501100011033), the Environment Research and Technology Development Fund of the Environmental Restoration and Conservation Agency of Japan (JPMEERF20202002), and the Northeastern Research Institute of Petrified Wood and Mineral Resources, Nakhon Ratchasima Rajabhat University, Thailand.Keywords 1. Introduction 2. Materials and methods 2.1. Data collection and notations 2.2. Ecological niche modeling 2.3. Data analyses 3. Results 3.1. Dominant Castanopsis species in East Asia today: richness and distribution patterns 3.2. Richness of dominant Castanopsis species shaped by climate change 3.3. Niche groups and niche breadths of dominant Castanopsis species 3.4. Climatically long-term stable refugia 4. Discussion 4.1. Richness of dominant Castanopsis species shaped by climate change 4.2. Niche groups and niche breadths of dominant Castanopsis species 4.3. Long-term stable refugia and conservation strategies 5. Conclusions CRediT authorship contribution statement Declaration of competing interest Acknowledgements Appendix A. Supplementary material Reference