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1.
Proc Natl Acad Sci U S A ; 121(12): e2318716121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38483991

RESUMEN

Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very-short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon. Airborne observations reported in this work identify the East Asian summer monsoon convection as an effective transport pathway that carried record-breaking levels of ozone-depleting Cl-VSLSs (mean organic chlorine from these VSLSs ~500 ppt) to the base of the stratosphere. These unique observations show total organic chlorine from VSLSs in the lower stratosphere over the Asian monsoon tropopause to be more than twice that previously reported over the tropical tropopause. Considering the recently observed increase in Cl-VSLS emissions and the ongoing strengthening of the East Asian summer monsoon under global warming, our results highlight that a reevaluation of the contribution of Cl-VSLS injection via the Asian monsoon to the total stratospheric chlorine budget is warranted.

2.
Int J Oral Maxillofac Implants ; 37(5): 891-904, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36170303

RESUMEN

PURPOSE: To evaluate the role of different healing abutment designs in compensating for the buccolingual volumetric tissue change that occurs following flapless single-tooth immediate extraction placement in the molar area. MATERIALS AND METHODS: Patients in need of extraction and replacement of a first or second molar in the mandible or maxilla were consecutively recruited. Immediately after extraction and implant placement, an abutment was connected. Five different types of abutments were randomly selected to be used for each case. The study population was divided into five categories according to abutment design: 5-mm diameter healing abutment (group 1); 6-mm diameter healing abutment (group 2); 7.5-mm diameter healing abutment (group 3); provisional restoration (group 4); and customized healing abutment (group 5). The buccopalatal dimension (BPD) was measured on the study casts at 1, 3, and 5 mm apical to the free gingival margin, and horizontal volumetric changes were compared between baseline and 2, 4, and 6 months. RESULTS: A total of 267 implants were inserted in 246 patients. The breakdown of placed implants for each group was as follows: 67 implants in group 1; 64 in group 2; 71 in group 3; 33 in group 4; and 32 in group 5. Changes in the mean horizontal ridge dimension were as follows. After 6 months in group 1, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 4.21 ± 0.158, 3.38 ± 0. 178 and 2.35 ± 0.178 mm. In group 2, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 3.16 ± 0.198, 2.56 ± 0.198, and 1.62 ± 0.198 mm. In group 3, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 2.53 ± 0.138, 2.16 ± 0.144, and 1.56 ± 0.144 mm. In group 4, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 1.11 ± 0.179, 1.23 ± 0.179, and 1.12 ± 0.179 mm. In group 5, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 0.25 ± 0.225, 0.30 ± 0.225, and 0.19 ± 0.225 mm. Mixed-effect regression and post hoc means comparisons were used to model the impact of the restoration technique, height of measurement, and time on BPD using a significance reference level of .05. Statistical analysis showed that the type of abutment, the height of measurement, and the time significantly influenced the BPD and that there were complex interaction effects between these variables. CONCLUSION: The observed volumetric soft tissue changes in the 6-month short-term follow-up appeared to vary based on the use of different healing abutment sizes that were connected to implants placed immediately after tooth extraction in the molar area. In particular, the use of a customized healing abutment resulted in preservation of the original horizontal dimension of the molar soft tissue.


Asunto(s)
Implantes Dentales de Diente Único , Implantes Dentales , Carga Inmediata del Implante Dental , Humanos , Diente Molar/cirugía , Extracción Dental/efectos adversos , Alveolo Dental/cirugía
3.
Sensors (Basel) ; 20(24)2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33371414

RESUMEN

In order to assess the limits and applicability of Pitot tubes for the measurement of flow velocity in narrow ducts, e.g., biomass burning plants, an optical, dual function device was implemented. This sensor, based on spectroscopic techniques, targets a trace gas, injected inside the stack either in bursts, or continuously, so performing transit time or dilution measurements. A comparison of the two optical techniques with respect to Pitot readings was carried out in different flow conditions (speed, temperature, gas composition). The results of the two optical measurements are in agreement with each other and fit quite well the theoretical simulation of the flow field, while the results of the Pitot measurements show a remarkable dependence on position and inclination of the Pitot tube with respect to the duct axis. The implications for the metrology of small combustors' emissions are outlined.

4.
Int J Mol Sci ; 20(11)2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31151286

RESUMEN

Dioxins and related compounds are environmental xenobiotics that are dangerous to human life, due to the accumulation and persistence in the environment and in the food chain. Cancer, reproductive and developmental issues, and damage to the immune system and endocrine system are only a few examples of the impact of such substances in everyday life. For these reasons, it is fundamental to detect and monitor these molecules in biological samples. The consolidated technique for analytical evaluation is gas chromatography combined with high-resolution mass spectrometry. Nowadays, the development of mid-infrared optical components like broadband laser sources, optical frequency combs, high performance Fourier-transform infrared spectroscopy, and plasmonic sensors open the way to new techniques for detection and real time monitoring of these organic pollutants in gaseous or liquid phase, with sufficient sensitivity and selectivity, and in short time periods. In this review, we report the latest techniques for the detection of dioxins, furans and related compounds based on optical and spectroscopic methods, looking at future perspectives.


Asunto(s)
Dioxinas y Compuestos Similares a la Dioxina/análisis , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Dioxinas y Compuestos Similares a la Dioxina/química , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/química , Humanos , Estructura Molecular , Análisis Espectral
5.
Low Urin Tract Symptoms ; 11(3): 104-108, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30182536

RESUMEN

OBJECTIVE: Acute urinary retention (AUR) is the sudden and painful inability to urinate spontaneously. AUR is one of the most significant complications of benign prostatic enlargement. The management of AUR is based on transurethral catheterization. Subsequent therapy is uncertain, but AUR seems to benefit from the use of alpha-blockers. The aim of this study was to evaluate the variables that could predict which patients would recover spontaneous micturition after trial without catheter. METHODS: The present prospective observational study included men with AUR in an Italian tertiary care institute in 2016. Patients were catheterized and treated orally with fluoroquinolones, alpha-blockers, and Serenoa repens extracts. Preoperative variables as age, C-reactive protein (CRP), previous prostate-specific antigen values, urinary retention volume, prostate volume, and scores on a modified International Prostate Symptom Score questionnaire (IPSS-4), were investigated in relation to spontaneous micturition recovery. RESULTS: Mean (±SD) age was 68.4 ± 7.1 years. Spontaneous and valid micturition recovery was observed in 11 patients (29.7%), whereas 26 (70.3%) needed to be catheterized again. The IPSS-4 score was significantly lower (9 vs 17; P < .001) and CRP values were significantly higher (43.00 vs 1.00 mg/dL; P < .001) in patients who recovered spontaneous micturition. The IPSS-4 scores and CRP showed an area under the curve of 0.85 and 0.87, respectively. for the prediction of spontaneous and valid micturition recovery. CONCLUSION: CRP and IPSS-4 could be useful tools to predict spontaneous micturition recovery after catheterization associated with medical therapy for AUR.


Asunto(s)
Próstata/patología , Hiperplasia Prostática/complicaciones , Recuperación de la Función , Retención Urinaria/fisiopatología , Retención Urinaria/terapia , Micción , Enfermedad Aguda , Anciano , Área Bajo la Curva , Proteína C-Reactiva/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Prospectivos , Hiperplasia Prostática/patología , Curva ROC , Índice de Severidad de la Enfermedad , Cateterismo Urinario , Retención Urinaria/etiología
6.
Sensors (Basel) ; 18(7)2018 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-30037111

RESUMEN

Trace gas concentration measurements in the stratosphere and troposphere are critically required as inputs to constrain climate models. For this purpose, measurement campaigns on stratospheric aircraft and balloons are being carried out all over the world, each one involving sensors which are tailored for the specific gas and environmental conditions. This paper describes an automated, portable, mid-infrared quantum cascade laser spectrometer, for in situ carbon monoxide mixing ratio measurements in the stratosphere and troposphere. The instrument was designed to be versatile, suitable for easy installation on different platforms and capable of operating completely unattended, without the presence of an operator, not only during one flight but for the whole period of a campaign. The spectrometer features a small size (80 × 25 × 41 cm3), light weight (23 kg) and low power consumption (85 W typical), without being pressurized and without the need of calibration on the ground or during in-flight operation. The device was tested in the laboratory and in-field during a research campaign carried out in Nepal in summer 2017, onboard the stratospheric aircraft M55 Geophysica. The instrument worked extremely well, without external maintenance during all flights, proving an in-flight sensitivity of 1⁻2 ppbV with a time resolution of 1 s.

7.
Urol Int ; 99(1): 77-83, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28482350

RESUMEN

Background/Aims/Objectives: We have investigated the clinical and physiological effects of Transfer Capacitive Resistive Energy (TCARE) therapy on men with Peyronie's disease (PD). METHODS: Ninety-six men with PD have been randomized in a 2:1 ratio to receive 3 sessions of TCARE therapy or sham therapy. Pain, penile curvature and erectile function have been assessed before the first treatment and up to 9 months after the end of treatment, using the Visual Analogue Scale for the pain, a goniometer to measure the degree of curvature using at-home photography and an International Index of Erectile Function (IIEF-5) questionnaire. RESULTS: A significant pain reduction at the end of the treatment in 51 (79.6%) patients (p < 0.01) of the treated group was observed. No significant improvements in the sham group (p = 0.23) have been observed. No statistical differences in the degree of curvature have been observed in both groups. No statistical improvements have been observed in the IIEF-5 questionnaire. Adverse events have not been reported. CONCLUSION: This is, to our knowledge, the first randomized, single-blind, sham-controlled study that shows that TCARE has a positive short-term clinical effect on pain in patients with PD. The feasibility and tolerability of this treatment produce an attractive new therapeutic option for men with PD.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Dolor/prevención & control , Induración Peniana/terapia , Pene/fisiopatología , Anciano , Capacidad Eléctrica , Impedancia Eléctrica , Terapia por Estimulación Eléctrica/efectos adversos , Humanos , Italia , Masculino , Persona de Mediana Edad , Dolor/diagnóstico , Dolor/etiología , Dimensión del Dolor , Erección Peniana , Induración Peniana/complicaciones , Induración Peniana/diagnóstico , Recuperación de la Función , Método Simple Ciego , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
8.
Arch Ital Urol Androl ; 87(1): 20-4, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25847891

RESUMEN

OBJECTIVE: To assess the proportion of patients with Peyronie's Disease (PD) and the possible association with its potential risk factors in the general population of the central and western Sicily in our weekly andrological outpatient clinic. MATERIALS AND METHODS: We recruited a sample of 279 consecutive patients consulting our andrological outpatient clinic. Two arms were created: the first one composed by PD patients (men with symptoms suggestive for PD), the second one composed by patients with other andrological diseases (control arm). For each patient we evaluated the age, cigarette smoking, diabetes, blood hypertension and erectile function. In the PD arm we administered validated questionnaires to determine the erectile function status by the International Index of Erectile Function 5 (IIEF-5) and the pain status during erection by the Visual Analogue Scale (VAS). A univariate analysis was conducted using R software. RESULTS: We enrolled 279 consecutive patients. The number of PD patients was 97 (34,7%). The univariate analysis showed a correlation between PD and cigarette smoking (p = 0.0242), blood hypertension (p < 0.001), erectile dysfunction (p < 0.001). No significant association was observed between diabetes and PD (p = 0.358). The median age of PD arm was 60 years and the median age of the control arm was 63,5 years; therefore the median age of PD arm resulted lower than the median age of the control arm (p = 0,031). CONCLUSIONS: Peyronie's disease is more common than we might think; furthermore it can be diagnosed among young patients. According to our results, cigarette smoking and blood hypertension may be considered statically significant risk factors for developing PD. On the contrary diabetes seems not to be a risk factor for PD. According to our results PD should be sought also in young patients. Further studies are necessary to confirm that removing the indicated risk factors may reduce the incidence of PD.


Asunto(s)
Complicaciones de la Diabetes/epidemiología , Disfunción Eréctil/epidemiología , Hipertensión/complicaciones , Hipertensión/epidemiología , Induración Peniana/epidemiología , Fumar/efectos adversos , Adulto , Anciano , Estudios de Casos y Controles , Disfunción Eréctil/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Induración Peniana/diagnóstico , Induración Peniana/etiología , Prevalencia , Factores de Riesgo , Índice de Severidad de la Enfermedad , Sicilia/epidemiología , Encuestas y Cuestionarios
9.
J Hazard Mater ; 274: 98-105, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-24794981

RESUMEN

The possibility to monitor in real-time the emission of dioxins produced by incineration of waste or by industrial processes is nowadays a necessity considering the high toxicity of these compounds, their persistence in the environment and their ability to bio-accumulate in the food chain. Recently it has been demonstrated the potentiality of detecting dioxins in carbon tetrachloride via MIR Quantum Cascade Lasers. A fundamental step in real time monitoring of dioxins emission is the possibility to recognize the most toxic congeners within complex mixtures and at low concentrations. Taking into account the lack of spectroscopic data about these very toxic environmental pollutants and the necessity to monitor their emissions we have recorded infrared spectra of 13 of the 17 most toxic congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) dissolved in carbon tetrachloride. In this way we have obtained a small database that we have used to test the ability of a linear regression algorithm to recognize each congener and its relative concentration in complex mixtures of these compounds.


Asunto(s)
Benzofuranos/análisis , Dibenzodioxinas Policloradas/análogos & derivados , Algoritmos , Benzofuranos/química , Tetracloruro de Carbono/química , Dibenzofuranos Policlorados , Modelos Lineales , Dibenzodioxinas Policloradas/análisis , Dibenzodioxinas Policloradas/química , Espectroscopía Infrarroja por Transformada de Fourier , Vibración
11.
Isotopes Environ Health Stud ; 41(4): 323-33, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16543188

RESUMEN

Diode-laser absorption spectroscopy finds increasing applications in the emerging field of stable isotope research. To meet the requirements of the water isotopes measurement challenge in environmental research, ways have to be found to cope with the present limitations of spectroscopic systems. In this article, we discuss an approach based on the Stark effect in molecular spectra to reduce the influence of time-dependent, unwanted background structures generally superimposed on the desired signal from the spectral feature under investigation. A road map to high-sensitivity isotopic ratio measurements of water isotopes is presented. On the basis of an Allan Variance analysis of measured data, the detection limits have been calculated as a function of the integration time. To achieve the required optical density of about 6 x 10(-7) for H(2)(17)O measurements, the duty cycle has to be optimized and the implementation of a sample modulation within an optical multipass cell is a promising approach to increase the stability of spectroscopic instrumentation required for ecosystem research and airborne atmospheric platforms.


Asunto(s)
Isótopos de Oxígeno/análisis , Espectrofotometría Infrarroja/métodos , Agua/análisis , Rayos Láser , Espectrofotometría Infrarroja/instrumentación , Volatilización , Agua/química
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