Tag: pubmed

BMJ. 2021 Sep 1;374:n2060. doi: 10.1136/bmj.n2060.

ABSTRACT

OBJECTIVE: To determine the risk of hospital admission with covid-19 and severe covid-19 among teachers and their household members, overall and compared with healthcare workers and adults of working age in the general population.

DESIGN: Population based nested case-control study.

SETTING: Scotland, March 2020 to July 2021, during defined periods of school closures and full openings in response to covid-19.

PARTICIPANTS: All cases of covid-19 in adults aged 21 to 65 (n=132 420) and a random sample of controls matched on age, sex, and general practice (n=1 306 566). Adults were identified as actively teaching in a Scottish school by the General Teaching Council for Scotland, and their household members were identified through the unique property reference number. The comparator groups were adults identified as healthcare workers in Scotland, their household members, and the remaining general population of working age.

MAIN OUTCOME MEASURES: The primary outcome was hospital admission with covid-19, defined as having a positive test result for SARS-CoV-2 during hospital admission, being admitted to hospital within 28 days of a positive test result, or receiving a diagnosis of covid-19 on discharge from hospital. Severe covid-19 was defined as being admitted to intensive care or dying within 28 days of a positive test result or assigned covid-19 as a cause of death.

RESULTS: Most teachers were young (mean age 42), were women (80%), and had no comorbidities (84%). The risk (cumulative incidence) of hospital admission with covid-19 was <1% for all adults of working age in the general population. Over the study period, in conditional logistic regression models adjusted for age, sex, general practice, race/ethnicity, deprivation, number of comorbidities, and number of adults in the household, teachers showed a lower risk of hospital admission with covid-19 (rate ratio 0.77, 95% confidence interval 0.64 to 0.92) and of severe covid-19 (0.56, 0.33 to 0.97) than the general population. In the first period when schools in Scotland reopened, in autumn 2020, the rate ratio for hospital admission in teachers was 1.20 (0.89 to 1.61) and for severe covid-19 was 0.45 (0.13 to 1.55). The corresponding findings for household members of teachers were 0.91 (0.67 to 1.23) and 0.73 (0.37 to 1.44), and for patient facing healthcare workers were 2.08 (1.73 to 2.50) and 2.26 (1.43 to 3.59). Similar risks were seen for teachers in the second period, when schools reopened in summer 2021. These values were higher than those seen in spring/summer 2020, when schools were mostly closed.

CONCLUSION: Compared with adults of working age who are otherwise similar, teachers and their household members were not found to be at increased risk of hospital admission with covid-19 and were found to be at lower risk of severe covid-19. These findings should reassure those who are engaged in face-to-face teaching.

PMID:34470747 | DOI:10.1136/bmj.n2060

BMJ. 2021 Sep 1;374:n1904. doi: 10.1136/bmj.n1904.

ABSTRACT

OBJECTIVE: To investigate the associations between air pollution and mortality, focusing on associations below current European Union, United States, and World Health Organization standards and guidelines.

DESIGN: Pooled analysis of eight cohorts.

SETTING: Multicentre project Effects of Low-Level Air Pollution: A Study in Europe (ELAPSE) in six European countries.

PARTICIPANTS: 325 367 adults from the general population recruited mostly in the 1990s or 2000s with detailed lifestyle data. Stratified Cox proportional hazard models were used to analyse the associations between air pollution and mortality. Western Europe-wide land use regression models were used to characterise residential air pollution concentrations of ambient fine particulate matter (PM_2.5), nitrogen dioxide, ozone, and black carbon.

MAIN OUTCOME MEASURES: Deaths due to natural causes and cause specific mortality.

RESULTS: Of 325 367 adults followed-up for an average of 19.5 years, 47 131 deaths were observed. Higher exposure to PM_2.5, nitrogen dioxide, and black carbon was associated with significantly increased risk of almost all outcomes. An increase of 5 µg/m³ in PM_2.5 was associated with 13% (95% confidence interval 10.6% to 15.5%) increase in natural deaths; the corresponding figure for a 10 µg/m³ increase in nitrogen dioxide was 8.6% (7% to 10.2%). Associations with PM_2.5, nitrogen dioxide, and black carbon remained significant at low concentrations. For participants with exposures below the US standard of 12 µg/m³ an increase of 5 µg/m³ in PM_2.5 was associated with 29.6% (14% to 47.4%) increase in natural deaths.

CONCLUSIONS: Our study contributes to the evidence that outdoor air pollution is associated with mortality even at low pollution levels below the current European and North American standards and WHO guideline values. These findings are therefore an important contribution to the debate about revision of air quality limits, guidelines, and standards, and future assessments by the Global Burden of Disease.

PMID:34470785 | DOI:10.1136/bmj.n1904

Chemosphere. 2021 Jun 19;283:131286. doi: 10.1016/j.chemosphere.2021.131286. Online ahead of print.

ABSTRACT

This study compares the differences between the distribution of trace elements and rare-earth elements (REEs) formed under reducing and oxidizing soil conditions during pedogenesis on carbonate bedrock. Terra rossa (TR) soils, representing pedogenesis under oxic conditions, and Cretaceous palaeosols (CP), representing pedogenesis under reducing conditions, were sampled on the Istrian peninsula. They were studied by ICP-MS, ICP-OES, XRF, XRD, sequential extraction and statistical analyses. The differences in trace-element behaviour between the TR and CP stem from different redox conditions, but the most remarkable difference was observed in the behaviour of the REEs. Statistical analyses revealed that in TR soils all the REEs showed a very positive correlation, while in CPs the light REEs and heavy REEs showed an internal, very positive correlation. TR soils have almost twice as much REEs as CPs. This difference is pedogenetic, as both materials have a very similar amount of REEs in the residual fraction. While TR soils have the same amount of REEs in fractions other than the residual fraction, CPs have almost no REEs in these fractions. Different REE patterns obtained from sequential extraction, such as a middle-REE enrichment and a positive Ce anomaly in TR soils and light-REE depletion, heavy-REE enrichment, positive Ce and Eu anomalies in CPs, contributed to an understanding of the redox and pedogenetic processes. This study successfully emphasized the influence of different redox conditions on the behaviour of trace and rare-earth elements during pedogenesis on a carbonate bedrock and the ability of the REEs to track pedogenetic processes.

PMID:34470733 | DOI:10.1016/j.chemosphere.2021.131286

Stat Med. 2021 Sep 1. doi: 10.1002/sim.9179. Online ahead of print.

ABSTRACT

Many studies, including self-controlled case series (SCCS) studies, are being undertaken to quantify the risks of complications following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19). One such SCCS study, based on all COVID-19 cases arising in Sweden over an 8-month period, has shown that SARS-CoV-2 infection increases the risks of AMI and ischemic stroke. Some features of SARS-CoV-2 infection and COVID-19, present in this study and likely in others, complicate the analysis and may introduce bias. In the present paper we describe these features, and explore the biases they may generate. Motivated by data-based simulations, we propose methods to reduce or remove these biases.

PMID:34470078 | DOI:10.1002/sim.9179

Opt Lett. 2021 Sep 1;46(17):4390-4393. doi: 10.1364/OL.435812.

ABSTRACT

The simulation of statistically accurate time-integrated dynamic speckle patterns using a physics-based model that accounts for spatially varying sample properties is yet to be presented in biomedical optics. In this Letter, we propose a solution to this important problem based on the Karhunen-Loève expansion of the electric field and apply our method to the formalisms of both laser speckle contrast imaging and diffuse correlation spectroscopy. We validate our technique against solutions for speckle contrast for different forms of homogeneous field and also show that our method can readily be extended to cases with spatially varying sample properties.

PMID:34470023 | DOI:10.1364/OL.435812

Opt Lett. 2021 Sep 1;46(17):4426-4429. doi: 10.1364/OL.437740.

ABSTRACT

In this Letter, we propose a real-time machine learning scheme of a tracking optical intensity-modulation and direct-detection (IMDD) system’s conditional distribution using linear optical sampling and inline Gaussian mixer modeling (GMM) programming. End-to-end conditional distribution tracking enables an adaptive decoding of optical IMDD signals, with robustness to the bias point shift of the optical intensity modulator. Experimental demonstration is conducted over a 20-Gbits/s optical pulse amplitude modulation-4 (PAM-4) modulation system. Optical PAM-4 signals are optically down-sampled by short pulses to 250 Msa/s. Then, statistical characters of signal distribution can be estimated using inline GMM processing. Due to the real-time learned distribution, intelligent decoding of received signals exhibits a perfect adaptation to the changing bias point of a Mach-Zendner intensity modulator, enhancing the communication reliability with bit error rate (BER) below 3.8⋅10^-3. In addition, the proposed scheme also provides the possibility of practical implementation to other machine learning signal decoding methods.

PMID:34470032 | DOI:10.1364/OL.437740

Opt Lett. 2021 Sep 1;46(17):4132-4135. doi: 10.1364/OL.431350.

ABSTRACT

The airborne measurement of a temperature profile from 10.5 km down towards ground (≈1.4km above sea level) during daytime by means of a lidar utilizing Rayleigh-Brillouin (RB) scattering is demonstrated for the first time, to our knowledge. The spectra of the scattered light were measured by tuning the laser (λ=354.9nm) over a 11 GHz frequency range with a step size of 250 MHz while using a Fabry-Perot interferometer as a spectral filter. The measurement took 14 min and was conducted over a remote area in Iceland with the ALADIN Airborne Demonstrator on-board the DLR Falcon aircraft. The temperature profile was derived by applying an analytical RB line shape model to the backscatter spectra, which were measured at different altitudes with a vertical resolution of 630 m. A comparison with temperature profiles from radiosonde observations and model temperatures shows reasonable agreement with biases of less than ±2K. Based on Poisson statistics, the random error of the derived temperatures is estimated to vary between 0.1 K and 0.4 K. The work provides insight into the possible realization of airborne lidar temperature profilers based on RB scattering.

PMID:34469957 | DOI:10.1364/OL.431350

Opt Lett. 2021 Sep 1;46(17):4386-4389. doi: 10.1364/OL.435799.

ABSTRACT

Nitrogen-vacancy color centers (NVs) in diamond have several potential applications ranging from quantum computing to data storage. However, artificial NVs are often close to the surface, which limits their spatial density and applicability. Here we demonstrate an effective and precise method for preparing deep single NVs in diamond. The method is based on a spatial-shaped femtosecond laser to overcome laser defocus in high-refractive materials, and realizes the preparation of single NVs at 95 µm. In addition, owing to the good energy distribution of the shaped laser focus, the single NVs exhibit a statistic yield of 56%±11% with excellent qualities. This processing method will contribute to the integration of color centers with emerging optical elements and high-density data storage.

PMID:34470022 | DOI:10.1364/OL.435799

J Healthc Qual. 2021 Aug 31. doi: 10.1097/JHQ.0000000000000322. Online ahead of print.

ABSTRACT

BACKGROUND: Opioid-induced respiratory depression (OIRD) is a serious complication that can lead to negative outcomes. There are known risk factors for OIRD; however, a lack of national guidelines for the prevention and early detection of OIRD exists.

METHODS: An evidence-based practice study was conducted to create an enhanced monitoring (EM) program. The EM program consisted of risk stratification of surgical spine patients, including the use of STOP-BANG screening for obstructive sleep apnea, capnography monitoring, use of home positive airway pressure therapy, capnography alarm optimization, hospitalist consultation, nursing education, and patient education.

RESULTS: Approximately 17% (N = 937/5,462) of surgical spine patients were enrolled in the EM program. Fifty-six percent of EM patients were monitored with capnography and had out of range end-tidal carbon dioxide levels 17% of the time. The rate of transfers to the intensive care unit (ICU) for OIRD decreased, though not statistically significant (p = .151).

CONCLUSIONS: The EM program with risk stratification was found to reduce transfers to the ICU for OIRD. Although not statistically significant, the decreased number of transfers was clinically significant. Engagement of the interprofessional team and capnography alarm parameter optimization helped to reduce nonactionable alarms.

PMID:34469926 | DOI:10.1097/JHQ.0000000000000322

Menopause. 2021 Aug 30. doi: 10.1097/GME.0000000000001847. Online ahead of print.

ABSTRACT

OBJECTIVE: This study explored the clinical management practices of healthcare providers who treat menopausal women in an urban Mid-South area. The study specifically examined their knowledge of prescribing and counseling related to the care of women who present with complaints or clinical findings of genitourinary syndrome of menopause.

METHODS: An electronic questionnaire was distributed to healthcare providers involved in the care of women undergoing menopausal transition spanning a variety of medical specialties. The questionnaire was distributed to academic program directors, coordinators, and ListServ administrators to forward to targeted respondents. Items included demographic questions, clinical knowledge, management practices, and preferences. Statistical analysis for associations between demographics was performed using Chi-squared tests and between age groups with Kruskal Wallis tests.

RESULTS: The final sample contained 106 healthcare providers. Respondents were demographically diverse and encompassed multiple levels of professional training including Attendings, Trainees (Residents and Fellows), as well as Advanced Practice Registered Nurses. Significant differences were noted in many areas examined in our questionnaire, comprising knowledge, management, counseling, and prescribing practices surrounding the treatment of genitourinary syndrome of menopause when accounting for training level, specialty, and years in practice. Among all respondents, 10.4% reported rarely or never discussing menopausal symptoms with their patients. Most respondents (76.4%) stated they had prescribed topical therapies for genitourinary syndrome of menopause, with over 90% of practitioners prescribing lubricants/moisturizers and estradiol cream; however, only 55% reported being familiar with the US Food and Drug Administration’s boxed warning on low-dose vaginal estrogen. Nearly half of the respondents (49%) reported being uncomfortable counseling about the boxed warning on low-dose vaginal estrogen.

CONCLUSION: This study identifies gaps in Mid-South healthcare providers’ awareness of the boxed warning on low-dose vaginal estrogen as well as their comfort level in providing counseling regarding the risks, benefits, and alternatives to vaginal estrogen. Integrated practice between physicians and Advanced Practice Registered Nurses can lead to a significant benefit to patients experiencing menopause as shared experience and knowledge are shared between each group. Our survey does reveal gaps in knowledge and practice for optimal outcomes for patients experiencing genitourinary syndrome of menopause. These results will be useful in providing continuing education to providers and more effective communication, evaluation, and treatment to patients.

PMID:34469937 | DOI:10.1097/GME.0000000000001847