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Se realiza un estudio preliminar sobre el comportamiento de la niebla en el Aeropuerto Internacional José Martí durante el período de 1975-2001. Se establecen características que permiten determinar la relación entre la ocurrencia de niebla y los factores de orden físico, local y sinóptico, así como elementos del tiempo presente que contribuyen a la formación de este fenómeno y el comportamiento de algunas de las variables meteorológicas que determinan su formación.

Medical Assistance in Dying (MAiD) is a complex process involving the person seeking care and their relatives. MAiD involves physical, psychosocial and spiritual needs, and consequently the involvement of an interdisciplinary team is beneficial. Therefore, updating the knowledge and skills of healthcare and social services professionals is critical. An interdisciplinary team from Laval University (Quebec, Canada) has developed a continuous training program for all health care and social services professionals who could be involved in the care of persons who request MAiD and their loved ones. It is crucial to assess whether the objectives of the continuous training program are being met, especially since this new training addresses several complex issues (legal, ethical, and clinical). Bandura's self-efficacy theory has been widely used to develop scales for assessing the impact of training programs and identifying knowledge gaps. Bandura's theory states that feeling secure in one's self-efficacy leads to self-determined motivation. Although there are various scales intended to measure self-efficacy in palliative care, none include self-efficacy for participating in the process surrounding MAiD. As a result, we aim to create a bilingual (English-French) interdisciplinary scale to assess self-efficacy for participating in the process surrounding MAiD. The scale will allow decision-makers and researchers to identify current knowledge gaps. It will also be useful for assessing the impact of current and future training programs addressing this end-of-life practice. In this work in progress, we briefly introduce the training program and the future steps in the development and validation of the scale., Competing Interests: None to declare., (© 2023 Tapp, Plaisance, Boudreault, St-Pierre, Desbiens, Poitras, Lemay, Urrea, Lapointe, Henry, Bravo; licensee Synergies Partners.)

Introduction: The report examined reciprocal within-person associations among maternal depressive symptoms and offspring depressive, anxiety and irritability symptoms from early childhood to adolescence using a random intercept cross-lagged panel model (RI-CLPM)., Method: Participants were 609 mother-child dyads participating in the Stony Brook Temperament Study. Child and maternal internalizing symptoms were assessed every 3 years from ages 3 to 15 using maternal report on the Child Behavior Checklist (CBCL) and Diagnostic Inventory for Depression, respectively., Results: At the between-person level, maternal depressive symptoms, and child depressive, anxiety, and irritability symptoms were all positively associated with one another. At the within-person level, greater within-person child anxiety symptoms at age 3 predicted both greater child anxiety and depressive symptoms at age 15 via greater child anxiety from ages 6 to 12, and greater within-person child irritability at age 3 predicted greater maternal depressive symptoms at age 15 via greater child irritability from ages 6 to 12., Conclusions: Findings reveal novel within-person developmental pathways from early childhood internalizing problems to later internalizing problems in both the child and mother. Intervention and prevention efforts should thus focus on early identification and prevention of childhood internalizing symptoms to reduce negative effects on both child and parent symptoms.

Abstract: ICNIRP 2020 guidelines have defined a practical temperature elevation threshold for human health effects, namely the operational adverse health effect threshold that forms the basis of the absorbed power and energy density basic restrictions. These basic restrictions for localized exposures at frequencies above 6 GHz were evaluated by comparing numerically computed temperature rise against the target temperature rise of 2.5 o C, which is the operational adverse health effect threshold divided by the occupational safety factor of 2. The numerical model employs the maximum absorbed power and energy density levels allowed by the occupational basic restriction for both pulsed and continuous wave exposures. These analyses were performed considering 3- and 4-tissue layer models and a variety of beam diameters, frequencies, and exposure durations. The smallest beam diameters were based on a study of theoretically achievable beam widths from half-wave resonant dipoles and show the impact of the averaging area on the computed temperature elevation. The results demonstrated that ICNIRP's assumed occupational safety factors in the frequency range above 6 GHz were not sufficiently maintained for all exposure scenarios and particularly for short pulse exposures at frequencies of 30 GHz or higher with small beam diameters. Worst-case tissue temperature elevations were estimated to be as much as 3.6 times higher than ICNIRP's target temperature increases. Consequently, the authors suggest a small modification in the application of the ICNIRP 2020 localized basic restrictions, thereby limiting the worst-case tissue temperature increases to 1.4 times the target value., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Health Physics Society.)

Steady state (SS) and transient temperature-rise in tissue from radiofrequency exposure forms the underlying basis for limits in international exposure guidelines. Periodically pulsed or intermittent exposures form a special case of having both peak and average levels, producing temperature-rise oscillations in the SS. Presented here is a method for determining tissue temperature-rise for periodic specific absorption rate (SAR) modulation having arbitrary waveform. It involves the finite difference solution of a form of the Pennes Bioheat Transfer equation (BHTE) and uses the concept of the transfer function and the Fast Fourier Transform (FFT). The time-dependent BHTE is converted to a SS harmonic version by assuming that the time-dependent SAR waveform and tissue temperature can both be represented by Fourier series. The transfer function is obtained from solutions of the harmonic BHTE for an assumed SAR waveform consisting of periodic impulses. The temperature versus time response for an arbitrary periodic SAR waveform is obtained from the inverse FFT of the product of the transfer function and the FFT of the actual SAR waveform. This method takes advantage of existing FFT algorithms on most computational platforms and the ability to store the transfer function for later re-use. The transfer function varies slowly with harmonic number, allowing interpolation and extrapolation to reduce the computational effort. The method is highly efficient for the case where repeated temperature-rise calculations for parameter variations in the SAR waveform are sought. Examples are given for a narrow, circularly symmetric beam incident on a planar skin/fat/muscle model with rectangular, triangular and cosine-pulsed SAR modulation waveforms. Calculations of temperature-rise crest factor as a function of rectangular pulse duty factor and pulse repetition frequency for the same exposure/tissue model are also presented as an example of the versatility of the method., (Creative Commons Attribution license.)

The assessment of health effects due to localized exposures from radiofrequency fields is facilitated by characterizing the steady-state, surface temperature rise in tissue. A closed-form analytical model was developed that relates the steady-state, surface temperature rise in multilayer planar tissues as a function of the spatial-peak power density and beam dimensions of an incident millimeter wave. Model data was derived from finite-difference solutions of the Pennes bioheat transfer equation for both normal-incidence plane waves and for narrow, circularly symmetric beams with Gaussian intensity distribution on the surface. Monte Carlo techniques were employed by representing tissue layer thicknesses at different body sites as statistical distributions compiled from human data found in the literature. The finite-difference solutions were validated against analytical solutions of the bioheat equation for the plane wave case and against a narrow-beam solution performed using a commercial multiphysics simulation package. In both cases, agreement was within 1-2%. For a given frequency, the resulting analytical model has four input parameters, two of which are deterministic, describing the level of exposure (i.e., the spatial-peak power density and beam width). The remaining two are stochastic quantities, extracted from the Monte Carlo analyses. The analytical model is composed of relatively simple functions that can be programmed in a spreadsheet. Demonstration of the analytical model is provided in two examples: the calculation of spatial-peak power density vs. beam width that produces a predefined maximum steady-state surface temperature, and the performance evaluation of various proposed spatial-averaging areas for the incident power density.

Kidney transplant recipients are at risk of pharmacological interactions and adverse drug reactions. Community pharmacists are uniquely poised to detect and intervene in cases of drug-related problems. The aims of this study were to develop and validate a list of explicit criteria to be used by community pharmacists to assess drug-related problems in kidney transplant patients, and to assess their frequency and their determinants. First, we used a modified RAND method where a panel of experts established the PART (Pharmacotherapy Assessment in Renal Transplant Patient) criteria. Then, we performed a cross-sectional study in which we applied the PART criteria to 97 prevalent kidney transplant recipients followed at a single university-affiliated center. The final list of PART criteria included 70 drug-related problems and was reliable (kappa: 0.88). An average of 1.2 drug-related problems per patient was detected when the PART criteria were applied, with 68% of patients having at least 1 problem. This figure was 1.4 per patient using the expert judgment of renal transplant pharmacists who had no access to the PART list. The total number of medications taken was the only factor associated with the number of drug-related problems (β: 0.27 for an increase of five medications, 95% CI 0.005, 0.547). The PART criteria provide a novel tool for community pharmacists to systematically detect drug-related problems in kidney transplant recipients.

Purpose: To assess 1.9 GHz radiofrequency (RF) field exposure on gene expression within a variety of discrete mouse brain regions using whole genome microarray analysis., Materials and Methods: Adult male C57BL/6 mice were exposed to 1.9 GHz pulse-modulated or continuous-wave RF fields for 4 h/day for 5 consecutive days at whole body average (WBA) specific absorption rates of 0 (sham), ∼0.2 W/kg and ∼1.4 W/kg. Total RNA was isolated from the auditory cortex, amygdala, caudate, cerebellum, hippocampus, hypothalamus, and medial prefrontal cortex and differential gene expression was assessed using Illumina MouseWG-6 (v2) BeadChip arrays. Validation of potentially responding genes was conducted by RT-PCR., Results: When analysis of gene expression was conducted within individual brain regions when controlling the false discovery rate (FDR), no differentially expressed genes were identified relative to the sham control. However, it must be noted that most fold changes among groups were observed to be less than 1.5-fold and this study had limited ability to detect such small changes. While some genes were differentially expressed without correction for multiple-comparisons testing, no consistent pattern of response was observed among different RF-exposure levels or among different RF-modulations., Conclusions: The current study provides the most comprehensive analysis of potential gene expression changes in the rodent brain in response to RF field exposure conducted to date. Within the exposure conditions and limitations of this study, no convincing evidence of consistent changes in gene expression was found in response to 1.9 GHz RF field exposure.

Purpose: This prospective randomized double-blind trial evaluates the efficacy of tranexamic acid (TA) to decrease blood losses and red blood cell transfusions in patients undergoing primary unilateral total hip replacement (THR)., Methods: Forty ASA class I to III patients received either iv TA 10 mg.kg(-1) bolus before surgery plus a 1 mg.kg(-1).hr(-1) infusion until wound closure (Group TA) or a placebo (Group P). Red blood cell transfusions were administered according to a standardized protocol., Results: One patient of Group P was excluded because of an erroneous diagnosis at enrollment. Total measured blood losses (Group TA: 1308 +/- 462 mL vs Group P: 1469 +/- 405 mL), preoperative hemoglobin levels (Group TA: 130.4 +/- 12.5 g.L(-1) vs Group P: 131.4 +/- 12.8 vs g.L(-1)), and seven-day postoperative hemoglobin values (Group TA: 97.8 +/- 11.8 g.L(-1) vs Group P: 102.9 +/- 12.2 g.L(-1)) were similar. Autologous whole blood was available in five patients of Group P and seven patients of Group TA. Fewer patients in Group TA required red blood cells (Group TA: 6/20 vs Group P: 13/19; P = 0.026) and allogenic red blood cell transfusions (Group TA: 0/20 vs Group P: 8/19; P = 0.0012). The median number of transfused unit per patient was also significantly less in patients of Group TA (0 unit) than in Group P (2 units; P = 0.03)., Conclusion: TA did not change measured blood losses but reduced red blood cell transfusion requirements in patients undergoing primary unilateral THR.

Purpose: The aims of this study are to determine if the injection of a single large dose of local anesthetics into the paravertebral space increases the risks of inducing toxicity compared with multiple small injections and to describe ropivacaine plasma concentrations resulting from paravertebral blockade., Methods: Paravertebral blockade was performed using a solution of 10 mL ropivacaine 0.75%, 10 mL lidocaine CO2 2% plus 0.1 mL epinephrine 1:1000 either by a single injection at T3 or T4 (Group S, n = 6) or by five injections of 4 mL each at T2 to T6 (Group M, n = 8). Blood samples were taken at zero, five, ten, 15, 20, 30, 45, 60 and 90 min and at two, three, four, five, six and eight hours. Ropivacaine and lidocaine plasma concentrations were measured by high performance liquid chromatography., Results: Maximal plasma concentrations were comparable for lidocaine: 2.6 +/- 1.3 (S) vs 2.6 +/- 0.8 microg x mL(-1) (M) and for ropivacaine: 1.3 +/- 0.2 (S) vs 1.3 +/- 0.1 microg x mL(-1) (M). Area under the plasma concentration-time curve was higher in Group M for lidocaine: 577.6 +/- 146.1 vs 401.7 +/- 53.2 mg x min(-1) x mL(-1) (P = 0.04) but similar for ropivacaine: 381.1 +/- 95.4 (M) vs 363.1 +/- 85.3 mg x min(-1) x L(-1) (S)., Conclusions: The injection of a single large bolus of local anesthetics into the paravertebral space does not increase its absorption. Maximal ropivacaine plasma concentrations resulting from paravertebral blockade are similar to those reported with equivalent doses of bupivacaine.