Olas de calor,temperatura ambiente y riesgo de infarto de miocardio: un estudio ecológico en la Comunidad de Madrid

Introduction and objectivesEpisodes of extreme heat are associated with increased morbidity and mortality in chronically-ill patients but there is a need to clearly establish the relationship between extreme heat and myocardial infarction. The aim of this study was to analyze the relationship between the incidence of ST-segment elevation myocardial infarction (STEMI) and maximum temperature, in particular during heat wave alert periods (HWAP).MethodsThe population studied consisted of confirmed STEMI cases registered in the Infarction Code of the Community of Madrid between June 2013 and June 2017. Incidence rate ratios (IRR) adjusted for trend and seasonality and 95%CI were estimated using time series regression models.ResultsA total of 6465 cases of STEMI were included; 212 cases occurred during the 66-day period of HWAP and 1816 cases during the nonalert summer period (IRR, 1.14; 95%CI, 0.96-1.35). The minimum incidence rate was observed at the maximum temperature of 18 °C. Warmer temperatures were not associated with a higher incidence (IRR,1.03; 95%CI, 0.76-1.41), whereas colder temperatures were significantly associated with an increased risk (IRR, 1.25; 95%CI, 1.02-1.54). No effect modification was observed by age or sex.ConclusionsWe did not find an increased risk of STEMI during the 66 days of HWAP in the Community of Madrid between June 2013 and June 2017. However, an increased risk was found during colder temperatures. No extra health resources for STEMI management are required during periods of extreme heat, but should be considered during periods of cold weather.     

Discharge Planning in the Era of Climate Change

We are living in an era of climate change, which has a tremendous impact on the health of our patients. Therefore, radiological nurses should be aware of and address climate change–related problems that impact patient health, such as heat, air quality, drought, wildfires, increased precipitation, and extreme weather. This article highlights the concerns and consequences of climate change on patients discharged from interventional radiological and other outpatient settings. Recommendations for discharge planning are provided to support, protect, and promote the health of patients in radiological services.     

Japanese Cedar (Cryptomeria japonica) Pollinosis in Jeju,Korea: Is It Increasing?

Jeju is an island in South Korea located in a temperate climate zone. The Japanese cedar tree (JC) has become the dominant tree species while used widely to provide a windbreak for the tangerine orchard industry. An increase in pollen counts precedes atopic sensitization to pollen and pollinosis, but JC pollinosis in Jeju has never been studied. We investigated JC pollen counts, sensitization to JC pollen, and JC pollinosis. Participants were recruited among schoolchildren residing in Jeju City, the northern region (NR) and Seogwipo City, the southern region (SR) of the island. The JC pollen counts were monitored. Sensitization rates to common aeroallergens were evaluated by skin prick tests. Symptoms of pollinosis were surveyed. Among 1,225 schoolchildren (49.6% boys, median age 13 years), 566 (46.2%) were atopic. The rate of sensitization to Dermatophagoides pteronyssinus (35.8%) was highest, followed by D. farinae (26.2%), and JC pollen (17.6%). In the SR, 156 children (23.8%) were sensitized to JC pollen; this rate was significantly higher than that in the NR (59 children, 10.4%, P<0.001). A significant increment in the sensitization rate for JC pollen with increasing school level was observed only in the SR. JC pollen season in the SR started earlier and lasted longer than that in the NR. JC pollen season in Jeju was defined as extending from late January to mid-April. The prevalence of JC pollinosis was estimated to be 8.5%. The prevalence differed significantly between the NR and SR (5.3% vs 11.3%, P<0.001), mainly due to the difference in sensitization rates. JC pollen is the major outdoor allergen for early spring pollinosis in Jeju. JC pollen season is from late January to mid-April. Warmer weather during the flowering season scatters more JC pollen in the atmosphere, resulting in a higher sensitization rate in atopic individuals and, consequently, making JC pollinosis more prevalent.     

非接触式医疗监测雷达研究进展

介绍了非接触式医疗监测雷达相比于传统的呼吸和心电监护仪的优势,从3种不同雷达体制的角度总结回顾了近10 a来医用生命监测雷达系统的研究现状,概括比较了呼吸和心跳信号的提取、分离、杂波抑制等算法,并指出了各种算法的优缺点,最后对非接触式生命监测雷达的发展趋势进行了探讨和展望.     

The Cold Weather Plan evaluation: an example of pragmatic evidence-based policy making?

Objectives

An evaluation of the Cold Weather Plan (CWP) for England 2011–2012 was undertaken in April 2012 to generate the basis for further revisions. It is widely considered good practice to formulate and revise policy on the basis of the best available evidence. This paper examines whether the evaluation is an example of pragmatic evidence-based policy-making.

Study design

A process evaluation with a formative multimethods approach.

Methods

An electronic survey and national workshop were conducted alongside the production of a number of summary reports from the Health Protection Agency surveillance systems and Met Office meteorological data. The Department of Health and the Met Office were consulted on how the evaluation recommendations shaped the revised CWP and Met Office Cold Weather Alerting System respectively.

Results

The Cold Weather Plan survey had 442 responses, a majority from Local Authorities, and from all regions of England. Thematic analysis generated qualitative data, which along with feedback from the workshop were synthesized into six main recommendations. Reviewing the new CWP and the Met Office Cold Weather Alerting System revealed significant modifications on the basis of the evaluation.

Conclusions

The evaluation sets the context for cold weather and health during the 2011–2012 winter. This study shows that the CWP 2012–2013 was revised on the basis of the national evaluation recommendations and is an example of pragmatic evidence-based policy-making.     

New insights into ice multiplication using remote-sensing observations of slightly supercooled mixed-phase clouds in the Arctic

Secondary ice production (SIP) can significantly enhance ice particle number concentrations in mixed-phase clouds, resulting in a substantial impact on ice mass flux and evolution of cold cloud systems. SIP is especially important at temperatures warmer than −10 ○C, for which primary ice nucleation lacks a significant number of efficient ice nucleating particles. However, determining the climatological significance of SIP has proved difficult using existing observational methods. Here we quantify the long-term occurrence of secondary ice events and their multiplication factors in slightly supercooled clouds using a multisensor, remote-sensing technique applied to 6 y of ground-based radar measurements in the Arctic. Further, we assess the potential contribution of the underlying mechanisms of rime splintering and freezing fragmentation. Our results show that the occurrence frequency of secondary ice events averages to <10% over the entire period. Although infrequent, the events can have a significant impact in a local region when they do occur, with up to a 1,000-fold enhancement in ice number concentration. We show that freezing fragmentation, which appears to be enhanced by updrafts, is more efficient for SIP than the better-known rime-splintering process. Our field observations are consistent with laboratory findings while shedding light on the phenomenon and its contributing factors in a natural environment. This study provides critical insights needed to advance parameterization of SIP in numerical simulations and to design future laboratory experiments.

Mixed-phase clouds, where supercooled cloud droplets and ice particles coexist, are frequently observed in the Arctic (1). These clouds play a critical role in the hydrological cycle and radiative energy balance, and they have unignorable impacts on sea ice loss and warming in the Arctic (2, 3). Recent theoretical and modeling investigations suggest that the number concentration of ice particles in mixed-phase clouds has a significant influence on the evolution of the cloud microphysical properties (4). Improper representation of ice formation compromises simulation of Arctic mixed-phase clouds in climate and regional models, which can cause considerable errors in the simulated radiative budget (5). Extensive modeling and laboratory studies have been conducted in recent years to investigate ice formation by ice nucleation, especially for heterogeneous ice nucleation for which nucleation is catalyzed by ice-nucleating particles (6–9). The fundamental underlying mechanisms of heterogeneous ice nucleation are still not fully understood, and the parameterizations that are widely used in atmospheric models are generated by fitting the results from laboratory experiments for various types of ice-nucleating particles. However, observed ice number concentrations can be several orders of magnitude greater than in simulations, especially in supercooled clouds with the temperature warmer than −10 ○C (hereafter, “slightly supercooled clouds”). In this temperature range, some biological aerosols originating from soil, plants, and the ocean are found to be efficient ice-nucleating particles that can trigger ice nucleation above −10 ○C (10–13). However, these efficient ice-nucleating particles are rare, suggesting that secondary ice production (SIP) is important (14).The best-known mechanism of SIP in slightly supercooled clouds is the rime-splintering process, also known as the Hallett–Mossop (HM) process. The HM process occurs preferentially for a temperature range of −3 ○C ∼ −8 ○C in which small ice splinters are generated during riming. The HM process has been demonstrated in the laboratory using a riming rod rotating in a small chamber filled with supercooled liquid droplets (15). SIP can also be caused by other mechanisms, such as collision fragmentation (16), freezing fragmentation (17, 18), and sublimation fragmentation (19). Details regarding the current understanding of those mechanisms can be found in recent review articles by Field et al. (20) and Korolev and Leisner (21). Among those mechanisms, the HM process is argued to be the most important mechanism for SIP in slightly supercooled clouds (20, 22). However, recent in situ measurements show that substantial numbers of needles and columns (signs of splintering) are observed in mixed-phase clouds without the presence of rimers (i.e., fast falling ice particles). Instead, the presence of large cloud droplets suggests that those observed SIP events are likely due to freezing fragmentation rather than the HM process (23). Pitter and Pruppacher (24) also found in a laboratory wind tunnel study that a noticeable fraction of freezing drizzle drops developed pronounced knobs or spikes, with the spikes breaking off in many cases. The theory of freezing fragmentation is further supported by recent laboratory experiments in which SIP was observed during freezing of a levitated droplet (17, 18). However, conditions for the occurrence of SIP are still poorly known and which SIP mechanism is dominant in mixed-phase clouds is far from clear.Although laboratory experiments can demonstrate the existence of SIP under certain controlled conditions, the idealized mechanisms used for the studies (e.g., rotating rod or a levitated droplet in a calm environment) are not directly translatable to characterizing SIP processes in atmospheric clouds. Therefore, parameterizations of SIP in models using laboratory data are of debatable accuracy (25) because we still do not understand SIP mechanisms at a fundamental level. Aircraft in situ measurements of ice particles and ice-nucleating particles can help to identify the occurrence of SIP in atmospheric clouds; however, statistical studies using such measurements are severely restricted by the small sampling volumes and limited coverage of aircraft flights (23, 26).Remote-sensing techniques provide an alternative way to observe atmospheric clouds, offering larger sampling volumes and longer periods compared with in situ measurements. These features are beneficial for observing processes that are transient and/or infrequent, as may be true for SIP. The occurrence of a SIP event in mixed-phase clouds is indicated by the presence of a large concentration of small ice particles, especially at warmer temperatures where these concentrations are unlikely to be due solely to primary ice nucleation. A common foundation of existing radar-based remote-sensing techniques for identification of SIP events includes the detection of small, nonspherical ice particles using polarimetric variables, such as differential reflectivity (ZDR) (the ratio of the power returned from horizontally versus vertically transmitted and received pulses) and linear depolarization ratio (LDR) (the ratio of cross-polarized versus copolarized power returned with respect to the polarization of transmitted pulses) (27, 28). Close to the time of SIP initiation, radar methods and in situ measurements are challenged alike, as distinguishing small spherical ice particles from cloud droplets is extremely difficult (4). As newly formed small ice particles prefer growing into needle-like ice crystals within the HM temperature zone (between −3 ○C and −8 ○C), they can then alter the value of ZDR and LDR compared with spherical hydrometers, which makes detection of SIP events possible using remote-sensing techniques. Most previous remote-sensing studies of SIP focus on specific cases, for which the thermodynamic properties of the subject mixed-phase clouds are carefully chosen such that the detection of nonspherical ice particles is a readily apparent signal of a SIP event in a small dataset (29, 30).In this study, we obtain a statistical understanding of SIP events. A remote-sensing technique is used to identify SIP events occurring within 6 y (March 2013 to May 2019) of ground-based observations of slightly supercooled liquid clouds. As detailed later, the technique determines the presence of SIP events using joint thresholds of radar LDR and spectral reflectivity and, moreover, quantifies the enhancement of needle-like particle concentrations (i.e., multiplication) based on the spectral reflectivity with respect to a base threshold. We link the occurrence of SIP to the presence of rimers and drizzle, and we estimate the enhancement in ice number concentration with respect to rimer velocity and drizzle size. We show that SIP events can significantly impact ice number concentrations locally when they occur, and we are able to assess the relative importance of two SIP mechanisms, finding that freezing fragmentation is more productive at SIP than the rime splintering normally regarded as the leading process for SIP.