Aims
To examine determinants of intention to leave a nursing position in rural and remote areas within the next year, for Registered Nurses or Nurse Practitioners (RNs/NPs) and Licensed Practical ...Nurses (LPNs).
Design
A pan‐Canadian cross‐sectional survey.
Methods
The Nursing Practice in Rural and Remote Canada II survey (2014–2015) used stratified, systematic sampling and obtained two samples of questionnaire responses on intent to leave from 1,932 RNs/NPs and 1,133 LPNs. Separate logistic regression analyses were conducted for RNs/NPs and LPNs.
Results
For RNs/NPs, 19.8% of the variance on intent to leave was explained by 11 variables; and for LPNs, 16.9% of the variance was explained by seven variables. Organizational commitment was the only variable associated with intent to leave for both RNs/NPs and LPNs.
Conclusions
Enhancement of organizational commitment is important in reducing intent to leave and turnover. Since most variables associated with intent to leave differ between RNs/NPs and LPNs, the distinction of nurse type is critical for the development of rural‐specific turnover reduction strategies. Comparison of determinants of intent to leave in the current RNs/NPs analysis with the first pan‐Canadian study of rural and remote nurses (2001–2002) showed similarity of issues for RNs/NPs over time, suggesting that some issues addressing turnover remain unresolved.
Impact
The geographic maldistribution of nurses requires focused attention on nurses' intent to leave. This research shows that healthcare organizations would do well to develop policies targeting specific variables associated with intent to leave for each type of nurse in the rural and remote context. Practical strategies could include specific continuing education initiatives, tailored mentoring programs, and the creation of career pathways for nurses in rural and remote settings. They would also include place‐based actions designed to enhance nurses' integration with their communities and which would be planned together with communities and nurses themselves.
摘要
目的
探讨注册护士或执业护士(RNs/NPs)和持证护士(LPNs)在未来一年内辞去农村和偏远地区护理职务的决定因素。
设计
泛加拿大横断面调查。
方法
加拿大农村和边远地区护理实践II调查(2014‐2015)过程中,采用分层、系统抽样的方法,对1932名注册护士/执业护士和1133名持证护士进行问卷调查,调查样本显示,共两名有意离职。分别对注册护士/执业护士和持证护士进行逻辑回归分析。
结果
19.8%注册护士或执业护士的离职意愿与11个变量相关,而16.9%持证护士的离职意愿与7个变量相关;组织承诺是唯一与注册护士/执业护士和持证护士离职意愿都相关的变量。
结论
强化组织承诺可以降低离职意愿和离职率,这一点至关重要。由于注册护士/执业护士和持证护士的离职意愿相关变量大多不同,护士类型的区分对于农村地区离职率降低策略的制定至关重要。将当前注册护士/执业护士分析中的离职意愿决定因素与首次泛加拿大农村和远程护士研究(2001‐2002年)进行比较,比较结果表明,随着时间的推移,注册护士/执业护士的问题趋同,表明部分离职相关问题仍未解决。
影响
当前,护士地理分布不均,因此需要关注护士的离职意愿。研究表明,医疗单位应该针对与农村和偏远地区不同类型护士离职意愿相关的特定变量制定政策。实际策略包括制定具体的继续教育计划,因地制宜编制指导计划,以及为农村和偏远地区的护士确定职业发展道路。此外,包括地方行动,旨在加强护士与社区的融合,同时为社区和护士作出规划。
Microlenses with typical stellar masses (a few M⊙) have traditionally been disregarded as potential sources of gravitational lensing effects at LIGO/Virgo frequencies, since the time delays are often ...much smaller than the inverse of the frequencies probed by LIGO/Virgo, resulting in negligible interference effects at LIGO/Virgo frequencies. While this is true for isolated microlenses in this mass regime, we show how, under certain circumstances and for realistic scenarios, a population of microlenses (for instance stars and remnants from a galaxy halo or from the intracluster medium) embedded in a macromodel potential (galaxy or cluster) can conspire together to produce time delays of order one millisecond, which would produce significant interference distortions in the observed strains. At sufficiently large magnification factors (of several hundred), microlensing effects should be common in gravitationally lensed gravitational waves. We explored the regime where the predicted signal falls in the frequency range probed by LIGO/Virgo. We find that stellar mass microlenses, permeating the lens plane, and near critical curves, can introduce interference distortions in strongly lensed gravitational waves. Lensed events with negative parity, or saddle points (which have never before been studied in the context of gravitational waves), and that take place near caustics of macromodels, are more likely to produce measurable interference effects at LIGO/Virgo frequencies. This is the first study that explores the effect of a realistic population of microlenses, including a macromodel, on strongly lensed gravitational waves.
Many young, massive stars are found in close binaries. Using population synthesis simulations we predict the likelihood of a companion star being present when these massive stars end their lives as ...core-collapse supernovae (SNe). We focus on stripped-envelope SNe, whose progenitors have lost their outer hydrogen and possibly helium layers before explosion. We use these results to interpret new Hubble Space Telescope observations of the site of the broad-lined Type Ic SN 2002ap, 14 years post-explosion. For a subsolar metallicity consistent with SN 2002ap, we expect a main-sequence (MS) companion present in about two thirds of all stripped-envelope SNe and a compact companion (likely a stripped helium star or a white dwarf/neutron star/black hole) in about 5% of cases. About a quarter of progenitors are single at explosion (originating from initially single stars, mergers, or disrupted systems). All of the latter scenarios require a massive progenitor, inconsistent with earlier studies of SN 2002ap. Our new, deeper upper limits exclude the presence of an MS companion star >8-10 M , ruling out about 40% of all stripped-envelope SN channels. The most likely scenario for SN 2002ap includes nonconservative binary interaction of a primary star initially 23 M . Although unlikely (<1% of the scenarios), we also discuss the possibility of an exotic reverse merger channel for broad-lined Type Ic events. Finally, we explore how our results depend on the metallicity and the model assumptions and discuss how additional searches for companions can constrain the physics that govern the evolution of SN progenitors.
In this work, BVRI light curves of 55 Type II supernovae (SNe II) from the Lick Observatory Supernova Search programme obtained with the Katzman Automatic Imaging Telescope and the 1 m Nickel ...telescope from 2006 to 2018 are presented. Additionally, more than 150 spectra gathered with the 3 m Shane telescope are published. We conduct an analyse of the peak absolute magnitudes, decline rates, and time durations of different phases of the light and colour curves. Typically, our light curves are sampled with a median cadence of 5.5 d for a total of 5093 photometric points. In average, V-band plateau declines with a rate of 1.29 mag (100 d)(exp −1), which is consistent with previously published samples. For each band, the plateau slope correlates with the plateau length and the absolute peak magnitude: SNe II with steeper decline have shorter plateau duration and are brighter. A time-evolution analysis of spectral lines in term of velocities and pseudo-equivalent widths is also presented in this paper. Our spectroscopic sample ranges between 1 and 200 d post-explosion and has a median ejecta expansion velocity at 50 d post-explosion of 6500 km s(exp −1) (H α line) and a standard dispersion of 2000 km s(exp −1). Nebular spectra are in good agreement with theoretical models using a progenitor star having a mass <16M⨀. All the data are available to the community and will help to understand SN II diversity better, and therefore to improve their utility as cosmological distance indicators.
Prostate cancer is characterized by a dependence upon androgen receptor (AR) signaling, and androgen deprivation therapy (ADT) is the accepted treatment for progressive prostate cancer. Although ADT ...is usually initially effective, acquired resistance termed castrate-resistant prostate cancer (CRPC) develops. PTEN and TP53 are two of the most commonly deleted or mutated genes in prostate cancer, the compound loss of which is enriched in CRPC. To interrogate the metabolic alterations associated with survival following ADT, we used an orthotopic model of Pten/Tp53 null prostate cancer. Metabolite profiles and associated regulators were compared in tumors from androgen-intact mice and in tumors surviving castration. AR inhibition led to changes in the levels of glycolysis and tricarboxylic acid (TCA) cycle pathway intermediates. As anticipated for inhibitory reciprocal feedback between AR and PI3K/AKT signaling pathways, pAKT levels were increased in androgen-deprived tumors. Elevated mitochondrial hexokinase 2 (HK2) levels and enzyme activities also were observed in androgen-deprived tumors, consistent with pAKT-dependent HK2 protein induction and mitochondrial association. Competitive inhibition of HK2-mitochondrial binding in prostate cancer cells led to decreased viability. These data argue for AKT-associated HK2-mediated metabolic reprogramming and mitochondrial association in PI3K-driven prostate cancer as one survival mechanism downstream of AR inhibition.
Co-located measurements of fine particulate matter (PM2.5) organic carbon (OC), elemental carbon, radiocarbon (14C), speciated volatile organic compounds (VOCs), and OH radicals during the CalNex ...field campaign provide a unique opportunity to evaluate the Community Multiscale Air Quality (CMAQ) model's representation of organic species from VOCs to particles. Episode average daily 23 h average 14C analysis indicates PM2.5 carbon at Pasadena and Bakersfield during the CalNex field campaign was evenly split between contemporary and fossil origins. CMAQ predicts a higher contemporary carbon fraction than indicated by the 14C analysis at both locations. The model underestimates measured PM2.5 organic carbon at both sites with very little (7% in Pasadena) of the modeled mass represented by secondary production, which contrasts with the ambient-based SOC / OC fraction of 63% at Pasadena. Measurements and predictions of gas-phase anthropogenic species, such as toluene and xylenes, are generally within a factor of 2, but the corresponding SOC tracer (2,3-dihydroxy-4-oxo-pentanoic acid) is systematically underpredicted by more than a factor of 2. Monoterpene VOCs and SOCs are underestimated at both sites. Isoprene is underestimated at Pasadena and overpredicted at Bakersfield and isoprene SOC mass is underestimated at both sites. Systematic model underestimates in SOC mass coupled with reasonable skill (typically within a factor of 2) in predicting hydroxyl radical and VOC gas-phase precursors suggest error(s) in the parameterization of semivolatile gases to form SOC. Yield values (α) applied to semivolatile partitioning species were increased by a factor of 4 in CMAQ for a sensitivity simulation, taking into account recent findings of underestimated yields in chamber experiments due to gas wall losses. This sensitivity resulted in improved model performance for PM2.5 organic carbon at both field study locations and at routine monitor network sites in California. Modeled percent secondary contribution (22% at Pasadena) becomes closer to ambient-based estimates but still contains a higher primary fraction than observed.
Environmental monitoring plays a central role in diagnosing climate and management impacts on natural and agricultural systems; enhancing the understanding of hydrological processes; optimizing the ...allocation and distribution of water resources; and assessing, forecasting, and even preventing natural disasters. Nowadays, most monitoring and data collection systems are based upon a combination of ground-based measurements, manned airborne sensors, and satellite observations. These data are utilized in describing both small- and large-scale processes, but have spatiotemporal constraints inherent to each respective collection system. Bridging the unique spatial and temporal divides that limit current monitoring platforms is key to improving our understanding of environmental systems. In this context, Unmanned Aerial Systems (UAS) have considerable potential to radically improve environmental monitoring. UAS-mounted sensors offer an extraordinary opportunity to bridge the existing gap between field observations and traditional air- and space-borne remote sensing, by providing high spatial detail over relatively large areas in a cost-effective way and an entirely new capacity for enhanced temporal retrieval. As well as showcasing recent advances in the field, there is also a need to identify and understand the potential limitations of UAS technology. For these platforms to reach their monitoring potential, a wide spectrum of unresolved issues and application-specific challenges require focused community attention. Indeed, to leverage the full potential of UAS-based approaches, sensing technologies, measurement protocols, postprocessing techniques, retrieval algorithms, and evaluation techniques need to be harmonized. The aim of this paper is to provide an overview of the existing research and applications of UAS in natural and agricultural ecosystem monitoring in order to identify future directions, applications, developments, and challenges.
Large-scale metal additive manufacturing (AM) provides a unique solution to rapidly develop prototype components with net-shape or near-net shape geometries. Specifically, additive friction stir ...deposition (AFSD) is a solid-state method for large-scale metal AM that produces near-net shape depositions capable of high deposition rates. As AFSD is utilized for a broader range of applications, there is a need to understand deposition strategies for larger and more complex geometries. In particular, components with larger surface areas will require overlapping deposition passes within a single layer. In this study, the AFSD process was used to create depositions utilizing multiple passes with a varying deposition path overlap width. The effects of overlapping parallel pass depositions on the mechanical and microstructural properties of aluminum alloy 7075 were examined. The grain size and microstructural features of the deposited material were analyzed to evaluate material mixing and plastic flow in the observed overlap regions. Additionally, hardness and tensile experiments were conducted to observe the relationship between the overlap width and as-deposited material behavior. In this study, an ideal overlap width was found that produced acceptable as-deposited material properties.
CD97, a member of the adhesion family of G-protein-coupled receptors (GPCRs), complexes with and potentiates lysophosphatidic acid (LPA) receptor signaling to the downstream effector RHOA. We show ...here that CD97 was expressed in a majority of thyroid cancers but not normal thyroid epithelium and that the level of CD97 expression was further elevated with progression to poorly differentiated and undifferentiated carcinoma. Intratumoral progression also showed that CD97 expression correlates with invasiveness and dedifferentiation. To determine the functional role of CD97, we produced a transgenic model of thyroglobulin promoter-driven CD97 expression. Transgenic CD97 in combination with Thrb(PV), an established mouse model of thyroid follicular cell carcinogenesis, significantly increased the occurrence of vascular invasion and lung metastasis. Expression of transgenic CD97 in thyroid epithelium led to elevated ERK phosphorylation and increased numbers of Ki67+ cells in developing tumors. In addition, tumor cell cultures derived from CD97 transgenic as compared with non-transgenic mice demonstrated enhanced, constitutive and LPA-stimulated ERK activation. In human thyroid cancer cell lines, CD97 depletion reduced RHO-GTP and decreased LPA-stimulated invasion but not EGF-stimulated invasion, further suggesting that CD97 influences an LPA-associated mechanism of progression. Consistent with the above, CD97 expression in human thyroid cancers correlated with LPA receptor and markers of aggressiveness including Ki67 and pAKT. This study shows an autonomous effect of CD97 on thyroid cancer progression and supports the investigation of this GPCR as a therapeutic target for these cancers.