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To study the clinical diagnosis of infectious keratitis by focusing microscopy. The data and charts of 30 patients were retrospectively analyzed. Four types of structures were observed by confocal microscopy in the HRT type II Rostock corneal model: trophozoites, bimural cysts, charter rings, and bright spots. Thirty patients (mean age 30.8 years, range 17-61 years, 12 males and 18 females) were divided into four groups according to the diagnosis determined by late microscopy, culture, treatment response and course of keratitis. The four groups were infectious keratitis (AK), suspected infectious keratitis (AK-suspect), bacterial keratitis (BK), fungal keratitis (FK). Bright spots were found in 100%, 100%, 40% and 55% of AK, AK-suspect, FK and BK groups, respectively. Under in vivo confocal microscopy, the sensitivity for the presence of bright spots in infectious keratitis was 100% (95% confidence interval [CI] 73.5% - 100.00%) and the specificity was 50% (CI 24.7% - 75.4%). The sensitivity was 67% (95% CI 34) when the only sign of infectivity was bright spot was excluded and only those with cysts, trophozoites, or charter rings were counted. The specificity was 94% (95% CI 69.8% - 99.8%). The relatively high rate of bright spots in noninfectious keratitis challenges the hypothesis that bright spots seen by confocal microscopy are a specific indication of infectious keratitis. [ABSTRACT FROM AUTHOR]

Single particle mass spectrometry (SPMS) is a useful, albeit not fully quantitative tool to determine chemical composition and mixing state of aerosol particles in the atmosphere. During a six-week field campaign in summer 2016 at a rural site in the upper Rhine valley near Karlsruhe city in southwest Germany, ~3.7 x 105 single particles were analyzed by a laser ablation aerosol particle time-of-flight mass spectrometer (LAAPTOF). Combining fuzzy classification, marker peaks, typical peak ratios, and laboratory-based reference spectra, seven major particle classes were identified. With the precise identification and well characterized overall detection efficiency (ODE) for this instrument, particle similarity can be transferred into corrected number fractions and further transferred into mass fractions. Considering the entire measurement period, Potassium rich and aromatics coated dust (class 5) dominated the particle number (46.5 % number fraction) and mass (36.0 % mass fraction); Sodium salts like particles (class 3) were the second lowest in number (3.5 %), but the second dominating class in terms of particle mass (25.3 %). This difference demonstrates the crucial role of particle mass quantification for SPMS data. Using corrections for maximum, mean, and minimum ODE, the total mass of the quantified particles measured by LAAPTOF accounts for ~12 %, ~25 %, and ~104 % of the total mass measured by an aerosol mass spectrometer (AMS) with a collection efficiency of 0.5. These two mass spectrometers show a good correlation (correlation coefficient γ > 0.6) regarding total mass for more than 70 % of the measurement time, indicating non-refractory species measured by AMS might originate from particles consisting of internally mixed non-refractory and refractory components. In addition, specific relationships of LAAPTOF ion intensities and AMS mass concentrations for non-refractory compounds were found for specific measurement periods. Furthermore, our approach allows for the first time to assign the non-refractory compounds measured by AMS to different particle classes. Overall AMS-nitrate was mainly arising from class 3, while class 5 was dominant during events rich in organic aerosol particles. [ABSTRACT FROM AUTHOR]

The laser ablation aerosol particles time-of-flight mass spectrometer (LAAPTOF, Aeromegt GmbH) is able to identify the chemical composition and mixing state of individual aerosol particles, and thus is a tool for elucidating their impacts on human health, visibility, ecosystem and climate. The overall detection efficiency (ODE) of the instrument we use was determined to range from ~(0.01 ± 0.01)% to ~(6.57 ± 2.38)% for polystyrene latex (PSL), ammonium nitrate (NH4NO3), and sodium chloride (NaCl) particles in the size rage of 200 to 2000nm. Reference mass spectra of 32 different particle types relevant for atmospheric aerosol (e.g. pure compounds NH4NO4, K2SO4, NaCl, oxalic acid, pinic acid, and pinonic acid; internal mixtures of e.g. salts, secondary organic aerosol, and metallic core-organic shell particles; more complex particles such as soot and dust particles) were determined. Our results show that internally mixed aerosol particles can result in spectra with new clusters of ions, rather than simply a combination of the spectra from the single components. An exemplary one-day ambient data set was analysed by classical Fuzzy-clustering leading to six different particle classes. Correlating these particle classes with the reference spectra as well as direct comparison of the ambient data with the reference spectra has proven how useful they are for the interpretation of field measurements, for e.g. grouping data, and identifying special particle types and potential sources. [ABSTRACT FROM AUTHOR]

Background: Data on resting heart rate and risk of all-cause and cardiovascular mortality are inconsistent; the magnitude of associations between resting heart rate and risk of all-cause and cardiovascular mortality varies across studies. We performed a meta-analysis of prospective cohort studies to quantitatively evaluate the associations in the general population.Methods: We searched PubMed, Embase and MEDLINE from inception to Jan. 1, 2015. We used a random-effects model to combine study-specific relative risks and 95% confidence intervals (CIs). We used restricted cubic spline functions to assess the dose-response relation.Results: A total of 46 studies were included in the meta-analysis, involving 1 246 203 patients and 78 349 deaths for all-cause mortality, and 848 320 patients and 25 800 deaths for cardiovascular mortality. The relative risk with 10 beats/min increment of resting heart rate was 1.09 (95% CI 1.07-1.12) for all-cause mortality and 1.08 (95% CI 1.06-1.10) for cardiovascular mortality. Compared with the lowest category, patients with a resting heart rate of 60-80 beats/min had a relative risk of 1.12 (95% CI 1.07-1.17) for all-cause mortality and 1.08 (95% CI 0.99-1.17) for cardiovascular mortality, and those with a resting heart rate of greater than 80 beats/min had a relative risk of 1.45 (95% CI 1.34-1.57) for all-cause mortality and 1.33 (95% CI 1.19-1.47) for cardiovascular mortality. Overall, the results did not differ after adjustment for traditional risk factors for cardiovascular disease. Compared with 45 beats/min, the risk of all-cause mortality increased significantly with increasing resting heart rate in a linear relation, but a significantly increased risk of cardiovascular mortality was observed at 90 beats/min. Substantial heterogeneity and publication bias were detected.Interpretation: Higher resting heart rate was independently associated with increased risks of all-cause and cardiovascular mortality. This indicates that resting heart rate is a predictor of all-cause and cardiovascular mortality in the general population. [ABSTRACT FROM AUTHOR]

Large increases in the number of low earth orbit satellites are projected in the coming decades [L. Schulz, K.-H. Glassmeier, Adv. Space Res. 67, 1002–1025 (2021)] with perhaps 50,000 additional satellites in orbit by 2030 [GAO, Large constellations of satellites: Mitigating environmental and other effects (2022)]. When spent rocket bodies and defunct satellites reenter the atmosphere, they produce metal vapors that condense into aerosol particles that descend into the stratosphere. So far, models of spacecraft reentry have focused on understanding the hazard presented by objects that survive to the surface rather than on the fate of the metals that vaporize. Here, we show that metals that vaporized during spacecraft reentries can be clearly measured in stratospheric sulfuric acid particles. Over 20 elements from reentry were detected and were present in ratios consistent with alloys used in spacecraft. The mass of lithium, aluminum, copper, and lead from the reentry of spacecraft was found to exceed the cosmic dust influx of those metals. About 10% of stratospheric sulfuric acid particles larger than 120 nm in diameter contain aluminum and other elements from spacecraft reentry. Planned increases in the number of low earth orbit satellites within the next few decades could cause up to half of stratospheric sulfuric acid particles to contain metals from reentry. The influence of this level of metallic content on the properties of stratospheric aerosol is unknown. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies have reported that ambient temperature may affect perinatal outcomes. However, whether extreme temperature affects the risk of preterm birth (PTB) remains controversial. Studies on the associations of extreme temperature with PTB subtypes are lacking. OBJECTIVES: We aimed to investigate the associations of extreme climate events with the risks of PTB and its subtypes, discerning possible modifiers. METHODS: Data on all singleton deliveries were obtained from the China Labor and Delivery Survey (CLDS), a nationwide investigation implemented in 2015 and 2016. PTB was defined as gestational weeks <37 and then categorized as early (24–34 wk) and late PTBs (35–36 wk), and clinical subtypes [spontaneous PTB, preterm premature rupture of the fetal membranes (PPROM), iatrogenic PTB]. Ambient temperature data were provided by the China National Weather Data Sharing System. Five heat indexes and five cold indexes were used to define heat waves and cold spells. Generalized linear mixed models with a random term by hospital unit were used to assess the associations of short-term prenatal extreme temperature exposure. The Cox proportional hazard regression model was applied to assess the nonlinear associations of low- or high-temperature exposure at the whole and different trimesters of pregnancy with the risk of PTB. Stratified analyses were conducted to assess the possible modification by geographic region and fetal sex. RESULTS: A total of 70,818 singleton births from 96 hospitals in China were included, among which 4,965 (7.01%) were PTBs. Exposure to extreme cold events 1 wk before delivery was associated with an increased PTB risk, with an adjusted odds ratio (aOR) [95% confidence intervals (CIs)] of 1.07 (95% CI: 1.04, 1.10) and 1.06 (1.04, 1.09) for the total days when the daily average temperature below the fifth percentile (fifth-days) and the 10th percentile (10th-days), 1.18 (1.04, 1.34) for the cold spells when the daily average temperature below the fifth percentile for two consecutive days (fifth-2D), 1.09 (1.03, 1.16) and 1.12 (1.06, 1.19) for the cold spells when the daily average temperature below the 10th percentile for three and two consecutive days (10th-3D and 10th-2D), respectively. Results of extreme temperature exposure during 2 weeks before delivery showed similarly significant associations. The association between cold spells and PTB tended to be stronger for late PTB than for early PTB. Cold spells were mainly associated with spontaneous PTB and late PPROM. A stratified analysis indicated that pregnant women in western and northern regions tended to be more sensitive to cold spells, and pregnant women with a female fetus appeared to be at a higher risk of PTB when exposed to cold spells. Pregnant women in late pregnancy were more susceptible to extreme temperatures. No significant or stable association was found between heat waves and preterm birth. DISCUSSION: Exposure to cold spells was associated with an increased risk of PTB, especially late, spontaneous PTB and PPROM. The associations appeared to be more pronounced in the north and west regions and in pregnancies with female fetuses. [ABSTRACT FROM AUTHOR]

Size, composition, and mixing state of individual aerosol particles can be analysed in real time using single particle mass spectrometry (SPMS). In SPMS, laser ablation is the most widely used method for desorption and ionization of particle components, often realizing both in one single step. Excimer lasers are well suited for this task due to their relatively high power density (107 W cm-2-1010 W cm-2) in nanosecond (ns) pulses at ultraviolet (UV) wavelengths, and short triggering times. However, varying particle optical properties and matrix effects make a quantitative interpretation of this analytical approach challenging. In atmospheric SPMS applications, this influences both the mass fraction of an individual particle that gets ablated, as well as the resulting mass spectral fragmentation pattern of the ablated material. The goal of the present study is to explore the use of shorter (femtosecond, fs) laser pulses for atmospheric SPMS, and to systematically investigate the influence of power density and pulse duration on airborne particle (polystyrene latex, SiO2, NH4NO3, NaCl, and custom-made core-shell particles) ablation and reproducibility of mass spectral signatures. We used a laser ablation aerosol time-of-flight single particle mass spectrometer (LAAPTOF, AeroMegt GmbH), originally equipped with an excimer laser (wavelength 193 nm, pulse width 8 ns, pulse energy 4 mJ), and coupled it to an fs-laser (Spectra Physics Solstice-100F ultrafast laser) with similar pulse energy, but longer wavelengths (266 nm with 100 fs and 0.2 mJ, 800 nm with 100 fs and 4 mJ, respectively). Generally, mass spectra exhibit an increase in ion intensities (factor 1 to 5) with increasing laser power density (~ 108 W cm-2 to ~ 1013 W cm-2) from ns- to fs-laser. At the same time, fs-laser ablation produces spectra with larger ion fragments and ion clusters, as well as clusters with oxygen, which does not render spectra interpretation more simple compared to ns-laser ablation. Quantification of ablated material remains difficult due to incomplete ionization of the particle. Furthermore, the fs-laser application still suffers from limitations in triggering it in a useful timeframe. Further tests are needed to test potential advantages of fs- over ns-laser ablation in atmospheric SPMS. [ABSTRACT FROM AUTHOR]

Background and Objectives: Few studies have investigated the effects of dietary theobromine intake on the cognitive performance of older adults. Therefore, we investigated these effects in older adults in the United States. Methods and Study Design: In this cross-sectional study, we used data (2011–2014) from the National Health and Nutrition Examination Survey. Intake of theobromine intake was obtained through two 24-h dietary recall interviews and was adjusted by energy. Cognitive performance was assessed using the animal fluency test, Consortium to Establish a Registry for Alzheimer’s Disease Word Learning subtest (CERAD), and Digit Symbol Substitution Test (DSST). Logistic regression and restricted cubic spline models were constructed to evaluate the correlation between the dietary intake of theobromine from different sources and the likelihood of low cognitive performance. Results: The fully adjusted model revealed that compared with the lowest quintile, the odds ratios (with 95% confidence intervals) of cognitive performance in the CERAD test were 0.42 (0.28–0.64), 0.34 (0.14– 0.83), 0.25 (0.07–0.87), and 0.35 (0.13–0.95) for the highest quintile of total theobromine intake and that from chocolate, coffee, and cream, respectively. Dose–response relationship analysis indicated nonlinear correlations between the likelihood of low cognitive performance and dietary theobromine (total intake and that from chocolate, coffee, and cream). An L-shaped relationship was observed between total theobromine intake and cognitive performance in the CERAD test. Conclusions: The dietary intakes of theobromine (total and that from chocolate, coffee, and cream) may protect older adults, particularly men, against low cognitive performance. [ABSTRACT FROM AUTHOR]

Background and Objectives: In daily life, the intake of dietary nutrients is mixed. However, evidence for the association between mixed dietary B vitamin intake and insulin resistance is limited. In this study, we estimated the joint effect of intake of various dietary B vitamins on insulin resistance. Methods and Study Design: This crosssectional study used data from the National Health and Nutrition Examination Survey 2011-2018. We included 1,628 middle-aged and 1,058 older adults without diabetes. Multivariable logistic regression and Bayesian kernel machine regression models were constructed. Results: In the multivariable logistic regression, when all B vitamins were included in the model, the ORs (95% CIs) of insulin resistance were 3.06 (1.00-9.37) and 0.42 (0.19-0.93) for the highest quartile of vitamin B-1 and B-12 intake in the middle-aged group when the lowest quartile was the reference. In the older group, no significant association was observed. In the Bayesian kernel machine regression analysis, a negative trend was noted between mixed B vitamin intake and insulin resistance in both examined groups. The univariate exposure-response function indicated that vitamin B-12 intake was negatively associated with insulin resistance in the middle-aged group, and that vitamin B-6 and dietary folate equivalent intakes were negatively associated with insulin resistance in older group. The bivariate exposure-response function indicated a potential interaction effect between dietary intake of vitamin B-12 and those of vitamin B-1, B-2, niacin, and dietary folate equivalent on insulin resistance in older people. Conclusions: Our results suggest that mixed dietary B vitamin intake tends to decrease the OR of insulin resistance both in middle-aged and older people. [ABSTRACT FROM AUTHOR]

The article focuses on a spatial meta-analysis by overlaying seven global biodiversity templates to identify conservation priority zones. It mentions that biodiversity loss is a social and ecological emergency, and calls have been made for the global expansion of protected areas (PAs). It also mentions that cost-effective zones (CEZs) cover around 38 percent of global terrestrial area.

Background Caspase-3 plays an important role in the initiation and maintenance of atrial fibrillation (AF), but little is known about the role of CASP3 variants in the susceptibility to atrial fibrillation (AF). The purpose of this study was to comprehensively investigate the association between common genetic variants of CASP3 gene and AF in Chinese Han population. Methods and results We investigated the association of five variants in CASP3 and the risk of AF in 889 AF patients and 1015 controls. The genotype distribution of the rs4647602 was significantly different between patients with AF and controls (p < 0.001), and the A allele frequency was significantly higher in AF patients than in controls (61.0% vs 53.2%; p < 0.001). Compared with CC genotype carriers, subjects with AA genotype had significantly increased susceptibility to AF (OR = 1.84, p < 0.001). Multivariable logistic regression analysis showed that the rs4647602 polymorphism was significantly associated with risk of AF under dominant, recessive and additive genetic model (OR, 1.44-1.64; all p < 0.001). There was no association between the other four SNPs (rs6948, rs2696056, rs4647602 and rs4647610) and risk of AF. Conclusion The rs4647602 polymorphism is independently associated with the risk of AF in Chinese Han population. [ABSTRACT FROM AUTHOR]

A highly regioselective 1,4-conjugate hydrocyanation of dienones using potassium hexacyanoferrate(II) as an original eco-friendly cyanide source, benzoyl chloride as a promoter and potassium carbonate as a catalyst is described. This protocol has advantages of non-toxic cyanating agent, high regioselectivity, high yield, and simple work-up procedure. [ABSTRACT FROM AUTHOR]