Determinants of Farm Households' Willingness to Accept (WTA) Compensation for Conservation Technologies: Ethiopia, Amhara Region, Northern Showa

The purpose of this study was to investigate and evaluate the WTP limits of irrigation water in the Sheva region of the Northern Amhara region of Ethiopia to understand whether irrigation water is feasible. Data were collected from primary research sources. An upright bivariate model was used to determine households' willingness to address irrigation water problems in the study area. Using data from a sample of 800 farmers, the results show that WTP is positive for irrigation water in the North Sheva region. The results show that the average household can obtain irrigation water for about 3,001.47 0.25 hectares of land in Ethiopia, which is a one-time irrigation land value of US$100.05 at the current exchange rate. In addition, the study found that household size, agricultural experience, household costs, irrigated land, livestock capital education level, and measured tropical livestock live-stock units had a positive effect on willingness to pay for irrigation water. Capital is adversely affected by family age, but market access for farmers is not guaranteed. Based on the pursuit, convincing reliability constraints, increasing market access through information and irrigation schemes, and increasing farmers' awareness of irrigation water and its use, is the efficient use of irrigation and irrigation water. Valid maintenance conditions are recommended. Stick to discipline

Corporate impression formation in online communities: a qualitative study

Purpose: This study aims to evaluate elements of corporate communication in online communities (OCs) and their influence on corporate impression formation. Interactive online platforms such as OCs are growing. Companies are discovering their importance and increasingly include OCs in their communication activities. The present study identifies the underlying components relevant to successful corporate communication in OCs, and further explore if and how online community members (OCMs) expect companies to communicate with them, explaining how corporate impressions are formed. Design/methodology/approach: A qualitative research method was chosen, consisting of two stages. In stage one, seventeen expert interviews with academics and practitioners were conducted, and in stage two, twelve OCMs were interviewed to clarify the concepts and gain new insights. Findings: The study gains new knowledge relating to corporate communication in OCs and image formation. Specifically, the authors identify and confirm important key constructs in corporate impression formation in OCs, namely, relevance of messages, communication style, social context cues, affiliation, perceived similarity, source credibility and interpersonal communication. Furthermore, a conceptual model is proposed on the relationship between communication elements relevant in online communities and their influence on corporate impression. Theoretical and practical implications: The study helps to refine existing concepts of corporate impression formation in OCs. It is suggested that understanding how corporate impression is formed in OCs helps companies to participate in virtual networks, improving their corporate impression

Epidemic Dynamics via Wavelet Theory and Machine Learning with Applications to Covid-19

We introduce the concept of epidemic-fitted wavelets which comprise, in particular, as special cases the number I(t) of infectious individuals at time t in classical SIR models and their derivatives. We present a novel method for modelling epidemic dynamics by a model selection method using wavelet theory and, for its applications, machine learning-based curve fitting techniques. Our universal models are functions that are finite linear combinations of epidemic-fitted wavelets. We apply our method by modelling and forecasting, based on the Johns Hopkins University dataset, the spread of the current Covid-19 (SARS-CoV-2) epidemic in France, Germany, Italy and the Czech Republic, as well as in the US federal states New York and Florid

Radio-frequency methods for Majorana-based quantum devices: fast charge sensing and phase diagram mapping

Radio-frequency (RF) reflectometry is implemented in hybrid semiconductor-superconductor nanowire systems designed to probe Majorana zero modes. Two approaches are presented. In the first, hybrid nanowire-based devices are part of a resonant circuit, allowing conductance to be measured as a function of several gate voltages ~40 times faster than using conventional low-frequency lock-in methods. In the second, nanowire devices are capacitively coupled to a nearby RF single-electron transistor made from a separate nanowire, allowing RF detection of charge, including charge-only measurement of the crossover from 2e inter-island charge transitions at zero magnetic field to 1e transitions at axial magnetic fields above 0.6 T, where a topological state is expected. Single-electron sensing yields signal-to-noise exceeding 3 and visibility 99.8% for a measurement time of 1 {\mu}s

Long-term use of antibiotics and risk of colorectal adenoma

Objective—Recent evidence suggests that antibiotic use, which alters the gut microbiome, is associated with an increased risk of colorectal cancer. However, the association between antibiotic use and risk of colorectal adenoma, the precursor for the majority of colorectal cancers, has not been investigated. Design—We prospectively evaluated the association between antibiotic use at age 20–39 and 40–59 (assessed in 2004) and recent antibiotic use (assessed in 2008) with risk of subsequent colorectal adenoma among 16,642 women aged ≥60 enrolled in the Nurses’ Health Study who underwent at least one colonoscopy through 2010. We used multivariate logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Results—We documented 1,195 cases of adenoma. Increasing duration of antibiotic use at age 20–39 (Ptrend=0.002) and 40–59 (Ptrend=0.001) was significantly associated with an increased risk of colorectal adenoma. Compared to non-users, women who used antibiotics for ≥2 months between age 20–39 had a multivariable OR of 1.36 (95% CI: 1.03–1.79). Women who used ≥2 months of antibiotics between age 40–59 had a multivariable OR of 1.69 (95% CI: 1.24–2.31). The associations were similar for low-risk vs. high-risk adenomas (size ≥1 cm, or with tubulovillous/villous histology, or ≥3 detected lesions), but appeared modestly stronger for proximal compared with distal adenomas. In contrast, recent antibiotic use within the past 4 years was not associated with risk of adenoma (Ptrend=0.44). Conclusions—Long-term antibiotic use in early to middle adulthood was associated with increased risk of colorectal adenoma

Isolated spin qubits in SiC with a high-fidelity infrared spin-to-photon interface

The divacancies in SiC are a family of paramagnetic defects that show promise for quantum communication technologies due to their long-lived electron spin coherence and their optical addressability at near-telecom wavelengths. Nonetheless, a mechanism for high-fidelity spin-to-photon conversion, which is a crucial prerequisite for such technologies, has not yet been demonstrated. Here we demonstrate a high-fidelity spin-to-photon interface in isolated divacancies in epitaxial films of 3C-SiC and 4H-SiC. Our data show that divacancies in 4H-SiC have minimal undesirable spin-mixing, and that the optical linewidths in our current sample are already similar to those of recent remote entanglement demonstrations in other systems. Moreover, we find that 3C-SiC divacancies have millisecond Hahn-echo spin coherence time, which is among the longest measured in a naturally isotopic solid. The presence of defects with these properties in a commercial semiconductor that can be heteroepitaxially grown as a thin film on shows promise for future quantum networks based on SiC defects.Comment: 26 pages, 4 figure

Stark Tuning and Electrical Charge State Control of Single Divacancies in Silicon Carbide

Neutrally charged divacancies in silicon carbide (SiC) are paramagnetic color centers whose long coherence times and near-telecom operating wavelengths make them promising for scalable quantum communication technologies compatible with existing fiber optic networks. However, local strain inhomogeneity can randomly perturb their optical transition frequencies, which degrades the indistinguishability of photons emitted from separate defects, and hinders their coupling to optical cavities. Here we show that electric fields can be used to tune the optical transition frequencies of single neutral divacancy defects in 4H-SiC over a range of several GHz via the DC Stark effect. The same technique can also control the charge state of the defect on microsecond timescales, which we use to stabilize unstable or non-neutral divacancies into their neutral charge state. Using fluorescence-based charge state detection, we show both 975 nm and 1130 nm excitation can prepare its neutral charge state with near unity efficiency.Comment: 12 pages, 4 figure