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1.
Sci Total Environ ; 917: 170221, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38280585

RESUMO

Light-absorbing aerosols heat the atmosphere; an accurate quantification of their absorption coefficient is mandatory. However, standard reference instruments (CAPS, MAAP, PAX, PTAAM) are not always available at each measuring site around the world. By integrating all previous published studies concerning the Aethalometers, the AE33 filter loading parameter, provided by the dual-spot algorithm, were used to determine the multiple scattering enhancement factor from the Aethalometer itself (hereinafter CAE) on an yearly and a monthly basis. The method was developed in Milan, where Aethalometer measurements were compared with MAAP data; the comparison showed a good agreement in terms of equivalent black carbon (R2 = 0.93; slope = 1.02 and a negligible intercept = 0.12 µg m-3) leading to a yearly experimental multiple scattering enhancement factor of 2.51 ± 0.04 (hereinafter CMAAP). On a yearly time base the CAE values obtained using the new approach was 2.52 ± 0.01, corresponding to the experimental one (CMAAP). Considering the seasonal behavior, higher experimental CMAAP and computed CAE values were found in summer (2.83 ± 0.12) whereas, the lower ones in winter/early-spring (2.37 ± 0.03), in agreement with the single scattering albedo behavior in the Po Valley. Overall, the agreement between the experimental CMAAP and CAE showed a root mean squared error (RMSE) of just 0.038 on the CMAAP prediction, characterized by a slope close to 1 (1.001 ± 0.178), a negligible intercept (-0.002 ± 0.455) and a high degree of correlation (R2 = 0.955). From an environmental point of view, the application of a dynamic (space/time) determination of CAE increases the accuracy of the aerosol heating rate (compared to applying a fixed C value) up to 16 % solely in Milan, and to 114 % when applied in the Arctic at 80°N.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38083187

RESUMO

Brain-machine interfaces (BMIs) based on motor imagery (MI) for controlling lower-limb exoskeletons during the gait have been gaining importance in the rehabilitation field. However, these MI-BMI are not as precise as they should. The detection of error related potentials (ErrP) as a self-tune parameter to prevent wrong commands could be an interesting approach to improve their performance. For this reason, in this investigation ErrP elicited by the movement of a lower-limb exoskeleton against subject's will is analyzed in the time, frequency and time-frequency domain and compared with the cases where the exoskeleton is correctly commanded by motor imagery (MI). The results of the ErrP study indicate that there is statistical significative evidence of a difference between the signals in the erroneous events and the success events. Thus, ErrP could be used to increase the accuracy of BMIs which commands exoskeletons.Clinical Relevance- This investigation has the purpose of improving brain-machine interfaces (BMIs) based on motor imagery (MI) by means of the detection of error potentials. This could promote the adoption of robotic exoskeletons commanded by BMIs in rehabilitation therapies.


Assuntos
Eletroencefalografia , Exoesqueleto Energizado , Eletroencefalografia/métodos , Retroalimentação , Índice de Massa Corporal , Extremidade Inferior , Marcha
3.
Artigo em Inglês | MEDLINE | ID: mdl-38083615

RESUMO

This study evaluates the performance of two convolutional neural networks (CNNs) in a brain-machine interface (BMI) based on motor imagery (MI) by using a small dataset collected from five participants wearing a lower-limb exoskeleton. To address the issue of limited data availability, transfer learning was employed by training models on EEG signals from other subjects and subsequently fine-tuning them to specific users. A combination of common spatial patterns (CSP) and linear discriminant analysis (LDA) was used as a benchmark for comparison. The study's primary aim is to examine the potential of CNNs and transfer learning in the development of an automatic neural classification system for a BMI based on MI to command a lower-limb exoskeleton that can be used by individuals without specialized training.Clinical Relevance- BMI can be used in rehabilitation for patients with motor impairment by using mental simulation of movement to activate robotic exoskeletons. This can promote neural plasticity and aid in recovery.


Assuntos
Interfaces Cérebro-Computador , Exoesqueleto Energizado , Humanos , Eletroencefalografia , Redes Neurais de Computação , Aprendizado de Máquina
4.
Sci Total Environ ; 791: 148277, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34119780

RESUMO

Accurate and temporally consistent measurements of light absorbing aerosol (LAA) heating rate (HR) and of its source apportionment (fossil-fuel, FF; biomass-burning, BB) and speciation (black and brown Carbon; BC, BrC) are needed to evaluate LAA short-term climate forcing. For this purpose, wavelength- and time-dependent accurate LAA absorption coefficients are required. HR was experimentally determined and apportioned (sources/species) in the EMEP/ACTRIS/COLOSSAL-2018 winter campaign in Milan (urban-background site). Two Aethalometers (AE31/AE33) were installed together with a MAAP, CPC, OPC, a low volume sampler (PM2.5) and radiation instruments. AE31/AE33 multiple-scattering correction factors (C) were determined using two reference systems for the absorption coefficient: 1) 5-wavelength PP_UniMI with low time resolution (12 h, applied to PM2.5 samples); 2) timely-resolved MAAP data at a single wavelength. Using wavelength- and time-independent C values for the AE31 and AE33 obtained with the same reference device, the total HR showed a consistency (i.e. reproducibility) with average values comparable at 95% probability. However, if different reference devices/approaches are used, i.e. MAAP is chosen as reference instead of a PP_UniMI, the HR can be overestimated by 23-30% factor (by both AE31/AE33). This became more evident focusing on HR apportionment: AE33 data (corrected by a wavelength- and time-independent C) showed higher HRFF (+24 ± 1%) and higher HRBC (+10 ± 1%) than that of AE31. Conversely, HRBB and HRBrC were -28 ± 1% and -29 ± 1% lower for AE33 compared to AE31. These inconsistencies were overcome by introducing a wavelength-dependent Cλ for both AE31 and AE33, or using multi-wavelength apportionment methods, highlighting the need for further studies on the influence of wavelength corrections for HR determination. Finally, the temporally-resolved determination of C resulted in a diurnal cycle of the HR not statistically different whatever the source- speciation- apportionment used.


Assuntos
Poluentes Atmosféricos , Calefação , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental , Material Particulado , Reprodutibilidade dos Testes
5.
Phys Rev Lett ; 104(13): 132502, 2010 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-20481879

RESUMO

We have analyzed data of the DISTO experiment on the exclusive pp --> pLambdaK+ reaction at 2.85 GeV to search for a strongly bound compact K- pp(approximately = X) state to be formed in the pp --> K+ + X reaction. The observed spectra of the K+ missing mass and the pLambda invariant-mass with high transverse momenta of p and K+ revealed a broad distinct peak of 26-sigma confidence with a mass M(X)=2267+/-3(stat)+/-5(syst) MeV/c2 and a width Gamma(X)=118+/-8(stat)+/-10(syst) MeV. The enormously large cross section indicates formation of a compact K- pp with a large binding energy of B(K)=103 MeV, which can be a possible gateway toward cold and dense kaonic nuclear matter.

6.
Int J Cosmet Sci ; 32(1): 35-46, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20412201

RESUMO

There is a continuing need to measure and communicate reliably the UVA protection offered by commercial sunscreens. To that end, the COLIPA (European Cosmetics Trade Association) 'In Vitro Sun Protection Methods' group has developed a new in vitro method for measuring UVA protection in a standardized, reproducible manner. The method is based on in vitro UV substrate spectrophotometry and convolution of resulting absorbance data with the action spectrum for the in vivo Persistent Pigment Darkening (PPD) endpoint to provide an in vitro UVA protection factor (UVAPF) which is correlated with an in vivo measure. This method has been published as a COLIPA guideline, used currently in European geographies for testing and labelling sunscreen products. This article summarizes two 'ring' studies, involving eight separate testing laboratories, which both defined critical parameters for the method and validated it. In Ring Study 1, eight laboratories tested the in vitro UV transmission of a total of 24 sunscreens and, from the data, a unit dose of UVA (D(0) of 1.2 J cm(-2)) was defined to provide a single irradiation step which, by taking into account potential sunscreen photo-instability, gave the closest agreement with in vivo UVAPF values. In Ring Study 2, eight laboratories tested the in vitro UV transmission of a total of 13 sunscreens using this single irradiation step and established a very good correlation (r(2) = 0.83; slope = 0.84, P < 0.0001) between resulting in vitro UVAPF values and corresponding values derived from the in vivo PPD method. This new method, therefore, can be used to provide a reliable in vitro metric to describe and label UVA efficacy in sunscreen products, in line with the EU Commission recommendation 2006/247/EC.


Assuntos
Pele/efeitos dos fármacos , Pele/efeitos da radiação , Protetores Solares/farmacologia , Raios Ultravioleta/efeitos adversos , Avaliação Pré-Clínica de Medicamentos/métodos , União Europeia , Humanos , Técnicas In Vitro , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta/métodos
7.
Skin Pharmacol Physiol ; 22(1): 31-44, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19122479

RESUMO

The recent European recommendation on the efficacy of sunscreen products requests now a minimum ratio of UVA/UVB protection. However, the visible and the infrared (IR) parts of the sun spectrum have received little attention concerning their possible contribution to skin damage. A common biophysical answer for the different wavelengths of the sun spectrum can be found in the creation of excess free radicals - mainly reactive oxygen species (ROS). Thanks to electron spin resonance spectroscopy applied to skin biopsies, we determined for the first time the free radical action spectrum covering UV and visible light (280-700 nm). Convolution of the action spectrum with sunlight spectral irradiance showed that 50% of the total skin oxidative burden was generated by visible light. Creation of ROS by visible light was experimentally confirmed by varying the illuminance of a spotlight. We also evidenced the creation of excess free radicals by near-IR radiation. In that case, free radical generation does not depend exclusively on the dose, but also on the skin temperature increase initiated by near-IR light. Some phenomena which are still unclear, such as the question about the deleterious or beneficial role of sunlight, are reviewed, implying the research on new protection strategies for the prevention of skin cancer.


Assuntos
Radicais Livres/metabolismo , Luz , Estresse Oxidativo/efeitos da radiação , Pele/efeitos da radiação , Biópsia , Relação Dose-Resposta à Radiação , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Técnicas In Vitro , Pele/metabolismo , Temperatura Cutânea , Raios Ultravioleta
8.
Hautarzt ; 60(4): 310-7, 2009 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-19319493

RESUMO

Experimental evidence suggests that the creation of free radicals--mainly reactive oxygen species (ROS)--is the common photobiological answer to the skin-sunlight interaction. The free radical action spectrum (wavelength dependency) for ultraviolet and visible light (280-700 nm) has been determined by quantitative ESR spectroscopy. Visible light produces around 50% of the total oxidative stress caused by sunlight. Reactive species like *O(-)(2), *OH and *CHR are generated by visible light. The amount of ROS correlates with the visible light intensity (illuminance). We demonstrated the creation of excess free radicals by near-infrared light (NIR, 700-1600 nm). Free radical generation does not depend exclusively on the NIR irradiance, but also on the NIR initiated skin temperature increase. The temperature dependence follows the physiological fever curve. Our results indicate that the complex biological system skin creates the same type of free radicals over the entire active solar spectrum. This general response will make it possible to define the beneficial or deleterious action of sunlight on human skin by introduction of a free radical threshold value.


Assuntos
Modelos Biológicos , Estresse Oxidativo/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Fenômenos Fisiológicos da Pele/efeitos da radiação , Animais , Humanos , Raios Infravermelhos , Luz , Raios Ultravioleta
9.
Sci Total Environ ; 686: 452-467, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185395

RESUMO

A closure experiment was conducted over Svalbard by comparing Lidar measurements and optical aerosol properties calculated from aerosol vertical profiles measured using a tethered balloon. Arctic Haze was present together with Icelandic dust. Chemical analysis of filter samples, aerosol size distribution and a full set of meteorological parameters were determined at ground. Moreover, scanning electron microscopy coupled with energy-dispersive X-ray (SEM-EDS) data were at disposal showing the presence of several mineralogical phases (i.e., sheet silicates, gypsum, quartz, rutile, hematite). The closure experiment was set up by calculating the backscattering coefficients from tethered balloon data and comparing them with the corresponding lidar profiles. This was preformed in three subsequent steps aimed at determining the importance of a complete aerosol speciation: (i) a simple, columnar refractive index was obtained by the closest Aerosol Robotic Network (AERONET) station, (ii) the role of water-soluble components, elemental carbon and organic matter (EC/OM) was addressed, (iii) the dust composition was included. When considering the AERONET data, or only the ionic water-soluble components and the EC/OM fraction, results showed an underestimation of the backscattering lidar signal up to 76, 53 and 45% (355, 532 and 1064 nm). Instead, when the dust contribution was included, the underestimation disappeared and the vertically-averaged, backscattering coefficients (1.45 ±â€¯0.30, 0.69 ±â€¯0.15 and 0.34 ±â€¯0.08 Mm-1 sr-1, at 355, 532 and 1064 nm) were found in keeping with the lidar ones (1.60 ±â€¯0.22, 0.75 ±â€¯0.16 and 0.31 ±â€¯0.08 Mm-1 sr-1). Final results were characterized by low RMSE (0.36, 0.08 and 0.04 Mm-1 sr-1) and a high linear correlation (R2 of 0.992, 0.992 and 0.994) with slopes close to one (1.368, 0.931 and 0.977, respectively). This work highlighted the importance of all the aerosol components and of the synergy between single particle and bulk chemical analysis for the optical property characterization in the Arctic.

10.
Cephalalgia ; 28(5): 541-52, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18318746

RESUMO

This study was an 8-month controlled trial to evaluate the effectiveness of a workplace educational and physical programme in reducing headache and neck and shoulder pain. Central registry office employees (n = 192; study group) and 192 peripheral registry office and central tax office employees (controls) in the city of Turin, Italy were given diaries for the daily recording of pain episodes. After 2 months, the study group only began the educational and physical programme. The primary end-point was the change in frequency of headache and neck and shoulder pain expressed as the number of days per month with pain, and as the proportion of subjects with a >or= 50% reduction of frequency (responder rate). The number of days of analgesic drug consumption was also recorded. Diaries completed for the whole 8 months were available for 169 subjects in the study group and 175 controls. The baseline frequency of headache (days per month) was 5.87 and 6.30 in the study group and in controls; frequency of neck and shoulder pain was 7.12 and 7.79, respectively. Mean treatment effects [days per month, 95% confidence interval (CI)] on comparing the last 2 months vs. baseline were: headache frequency -2.45 (-3.48, -1.43); frequency of neck pain -2.62 (-4.09, -1.16); responder rates (odds ratio, 95% CI) 5.51 (2.75, 11) for headache, 3.10 (1.65, 5.81) for neck and shoulder pain, and 3.08 (1.06, 8.90) for days with analgesic drug consumption. The study suggests that an educational and physical programme reduces headache and neck and shoulder pain in a working community.


Assuntos
Cefaleia/prevenção & controle , Cervicalgia/prevenção & controle , Doenças Profissionais/prevenção & controle , Educação de Pacientes como Assunto/estatística & dados numéricos , Modalidades de Fisioterapia/estatística & dados numéricos , Dor de Ombro/prevenção & controle , Adulto , Comorbidade , Feminino , Cefaleia/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Cervicalgia/epidemiologia , Doenças Profissionais/epidemiologia , Terapia Ocupacional/métodos , Prevalência , Dor de Ombro/epidemiologia , Resultado do Tratamento
11.
Int J Cosmet Sci ; 29(6): 451-60, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18489384

RESUMO

The aim of the study was to develop a simple reproducible and reliable in vitro water resistance (WR) method to assess the sun care products. This paper is the result of a scientific collaboration between seven different international industrial laboratories and testing institutes. The same group has already achieved an in vitro protocol for the sun protection factor (SPF) determination [1]. The in vitro WR of sunscreens was tested by applying the same principle as in vivo, which determines the percentage of retention of sunscreen products by assessing the SPF before and after water immersion. Special care was taken to study the parameters influencing the WR and the possibility to follow the kinetics of sunscreen retention during water immersion. The influence of different water qualities has been tested, and osmosed water (1-3 microS cm(-1)) was chosen for the main ring study. Measurement was carried out after 5, 20 and 40 min of immersion. Histograms of selected products demonstrate the percentage of WR at all measuring times and centres, and the regression coefficient to the in vivo determination was shown and statistical calculations clearly demonstrate the reproducibility of the results between the different evaluation centres. The presented method is a practical, convenient and relevant tool for WR screening of sun care and skin care products. It even has the potential to be the starting point for the replacement of the in vivo method in future.

12.
Surg Res Pract ; 2016: 4120214, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27747272

RESUMO

Introduction. Acute appendicitis is the most common surgical emergency in the pediatric population. The peak incidence occurs in the first decade of life, while it is uncommon to face appendicitis in children younger than 5 years of age. Laparoscopy is now demonstrated to be the optimal approach also to treat complicated appendicitis, but in very young children this standardized operation is not always easy to perform. Material and Methods. From January 2009 to December 2015 we operated on 525 acute appendicitis, with 120 patients less than 5 years of age. Results. 90 children had a complicated appendicitis (localized or diffuse peritonitis): 43 (48%) were operated on by open approach and 47 (52%) by laparoscopy. The overall incidence of postoperative complications was greater in the open appendectomy group (63% versus 26%) and all severe complications requiring reintervention (6% of cases: 3 postoperative abscesses resolved with ultrasound guided percutaneous abscess drainage; 1 tubal surgery for salpingitis; 1 adhesion-related ileus requiring relaparotomy) were mostly associated with open surgery. Conclusions. Laparoscopic surgery resulted as the best approach for treating complicated appendicitis also in younger children, with minor and less severe postoperative complications compared to open surgery.

13.
J Laryngol Otol ; 129(7): 638-43, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26091105

RESUMO

OBJECTIVE: This study aimed to examine tinnitus prevalence in patients with different types of headache and the relationship between tinnitus and the pericranial muscle tenderness and cervical muscle tenderness scores. METHODS: A cross-sectional study was conducted of 1251 patients with migraine and/or myogenous pain, arthrogenous temporomandibular joint disorders and tension-type headache. Standardised palpation of the pericranial and cervical muscles was carried out and univariable and multivariable analysis was used to measure the odds ratio of suffering tinnitus by the different diagnoses and muscular tenderness grade. RESULTS: A univariable analysis showed that myogenous pain, pericranial muscle tenderness and cervical muscle tenderness scores, sex, and age were associated with tinnitus. When a multivariable model including only age, sex and a headache diagnosis was used, myogenous pain, migraine and age were found to be associated with tinnitus. When muscle tenderness scores were also included, only the cervical muscle tenderness and pericranial muscle tenderness scores were found to be significantly associated with tinnitus. CONCLUSION: In a population of patients with headache and craniofacial pain, tinnitus was related to increased cervical muscle tenderness and pericranial muscle tenderness scores, rather than to any particular form of headache.


Assuntos
Dor Facial/epidemiologia , Transtornos da Cefaleia/epidemiologia , Transtornos de Enxaqueca/epidemiologia , Mialgia/epidemiologia , Transtornos da Articulação Temporomandibular/epidemiologia , Zumbido/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Estudos Transversais , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Sistema de Registros , Estudos Retrospectivos , Estatística como Assunto , Cefaleia do Tipo Tensional/epidemiologia , Zumbido/etiologia , Adulto Jovem
14.
Cancer Gene Ther ; 7(5): 789-98, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10830726

RESUMO

Recently, a new p53 derivative has been designed, namely chimeric tumor suppressor 1 (CTS1), in which the p53 domains that are known to mediate p53 inactivation have been replaced. In this study, the antitumoral activity of CTS1 mediated by adenovirus vector has been evaluated in comparison with a p53 adenovirus vector in various human tumor cell lines. In vitro, in terms of cell growth inhibition, the CTS1 vector was significantly (P < .01) more efficient (2- to 7-fold) than the p53 vector in tumor models overexpressing an inhibitor of p53, murine double minute-2. This result was confirmed in vivo in a pre-established tumor developed in nude mice. In an osteosarcoma model overexpressing murine double minute-2, we have shown a significantly (P < .05) higher tumor growth delay with the CTS1 vector compared with the p53 vector (25.6 days compared with 12.4 days). Furthermore, both in vitro and in vivo, we have shown that this higher inhibition of tumor growth with the CTS1 vector was correlated with a higher induction of apoptosis. Therefore, CTS1 is a potentially improved tumor suppressor gene for the treatment of human tumors resistant to wild-type p53 gene therapy.


Assuntos
Genes p53/genética , Terapia Genética/métodos , Neoplasias Experimentais/terapia , Proteínas Nucleares , Proteínas Proto-Oncogênicas/metabolismo , Adenoviridae/genética , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/terapia , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Citometria de Fluxo , Técnicas de Transferência de Genes , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Neoplasias Pulmonares/terapia , Camundongos , Camundongos Nus , Transplante de Neoplasias , Osteossarcoma/terapia , Proteínas Proto-Oncogênicas c-mdm2 , Fatores de Tempo , Células Tumorais Cultivadas
15.
Dig Liver Dis ; 32(5): 406-11, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11030186

RESUMO

BACKGROUND: Pancreatic exocrine insufficiency is a common condition in patients with cystic fibrosis. Large amounts of pancreatic enzyme supplements are required to reduce malabsorption but patient compliance is not always optimal. AIMS: To compare patients' preference and the efficacy of two enteric coated microsphere preparations in patients with cystic fibrosis. PATIENTS: Patients with pancreatic exocrine insufficiency due to cystic fibrosis. METHODS: Patients were assigned to the crossover treatment with Creon or Pancrease for 1 week and then to the alternative treatment. Patients had to follow a fixed diet (at least 2 g fat/kg) and had to assume 1000 units lipase/g fat. The evaluation parameters were: patients' preference, acceptance of therapy, stool fat excretion, stool weight, gastrointestinal symptoms, and tolerance. RESULTS AND CONCLUSIONS: Of the 33/60 patients who expressed a preference for one of the two treatments, 30 preferred Creon while only 3 patients preferred Pancrease (p<0.001). No difference between the two treatments was observed regarding stool characteristics, gastrointestinal symptoms and tolerance. The mean number of capsules taken daily was reduced by 35% with Creon. The results of this study showed a preference in favour of Creon probably due to the reduction of daily capsule intake of 35%, supporting digestion as well as Pancrease.


Assuntos
Fibrose Cística/complicações , Insuficiência Pancreática Exócrina/tratamento farmacológico , Fármacos Gastrointestinais/administração & dosagem , Pancrelipase/administração & dosagem , Adolescente , Adulto , Amilases/administração & dosagem , Cápsulas , Criança , Tolerância a Medicamentos , Endopeptidases/administração & dosagem , Insuficiência Pancreática Exócrina/etiologia , Feminino , Humanos , Lipase/administração & dosagem , Masculino , Microesferas , Aceitação pelo Paciente de Cuidados de Saúde , Segurança
16.
Int J Cosmet Sci ; 24(2): 63-70, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18498497

RESUMO

In the present study, we have described an in vitro spectroscopic method to evaluate the sunscreen products for UVA sun protection factor. The roughened PMMA plates have been used as a transparent substrate on to which the test product is spread. The UVA protection factors have been deduced from the UV-transmittance data measured in the UVA area. In order to be as close as possible to the in vivo protection factors, issued from the PPD end-point, the treated polymethylmethacrylate (PMMA) plates are submitted to different UV-irradiation doses, before the measurement. The correlation in vitro/in vivo is poor when the sunscreens are not irradiated. A UV dose of about 2 minimal pigmenting dose (MPD) is enough to achieve a good correlation between in vitro and in vivo data issued from the 13 tested sunscreens. These results are consistent with the fact that the photostability of sunscreens is challenged during an in vivo PPD test.

17.
Homo ; 53(3): 247-54, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12733398

RESUMO

Cranial trepanation is a practice known since prehistory in various, often geographically distant populations. In this work are presented two early medieval trepaned skulls. The first skull comes from Canosa in Apulia (6th-7th c. AD; according to radiocarbon dating), the second is from Ticineto Alessandrino (5th-8th c. AD). The skull of Canosa shows a single perforation on the bregmatic quadrant of the right parietal, whereas the Ticineto skull presents three lesions of different shapes and sizes. Two perforations are on the left parietal and the other is on the right parietal. The lesions of the Ticineto skull can be referred to a therapeutic operation following a trauma, with survival of the individual. In the Canosa skull the absence of a healing reaction suggests a pathological process, without survival of the subject. Moreover, a particular ritual practice cannot be excluded (i.e. a post-mortem trepanation).


Assuntos
Trepanação/história , Traumatismos Craniocerebrais/história , Traumatismos Craniocerebrais/cirurgia , Feminino , História Medieval , Humanos , Itália
18.
J Cosmet Sci ; 54(5): 463-81, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14605688

RESUMO

Irregularities in the geometry of sunscreen films spread on rough areas, like skin, is often presented as being the main cause of the degree of UV absorption achieved by the UV filters that are inside. Until now, only the step film, a model invented by O'Neill, was simple enough to calculate UV data close to in vitro experimental data, after determination of a limited number of fraction areas with their corresponding thickness. However, such models are obviously too simple to represent a real situation. In the present work, more complex distributions of film thickness were calculated, with an infinite number of individual heights. Realistic models were achieved via a probability function. The consequences for UV absorption were deduced, and the calculated UV data were compared to experimental in vitro data on sunscreen products measured after being spread on a roughened PMMA substrate. The latter substrate was previously selected for its ability to achieve a good correlation with in vivo SPF. An optimized version of the continuous mathematical model was finally determined in order to achieve UV curves, similar in shape and intensity to the experimental ones. The latter model can be used to predict realistic SPF values.


Assuntos
Modelos Teóricos , Protetores Solares/química , Protetores Solares/normas , Raios Ultravioleta
19.
Environ Sci Pollut Res Int ; 21(17): 10163-73, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24793066

RESUMO

The gas/particle partitioning coefficient K p, of a semivolatile compound is a key parameter for its atmospheric fate. The most complete method of predicting K p for polycyclic aromatic hydrocarbons (PAHs) is offered by the dual model, as it describes both the adsorption on soot and absorption into organic matter processes. However, experimental and model data exist almost exclusively for PAHs. In order to bridge this gap, experimental data on the phase partitioning of both PAHs and n-alkanes were collected at an urban and a remote site. Moreover, all the necessary parameters (e.g., octanol-air and soot-air partitioning coefficients) for the dual model have been collected and updated or (if missing) estimated for the first time. The results point out that both absorption and adsorption seem to contribute to the partitioning of PAHs and n-alkanes. However, it seems that the dual model always underestimates the particle sorption not only for PAHs but also for n-alkanes.


Assuntos
Poluentes Atmosféricos/química , Alcanos/química , Gases/química , Modelos Químicos , Material Particulado/química , Hidrocarbonetos Policíclicos Aromáticos/química , Adsorção , Poluentes Atmosféricos/análise , Alcanos/análise , Monitoramento Ambiental , Gases/análise , Modelos Teóricos , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Fuligem
20.
Talanta ; 120: 283-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24468371

RESUMO

The paper describes the characterization of polycyclic aromatic hydrocarbons (PAHs) in atmospheric aerosol samples using Gas Chromatography-Mass Spectrometry analysis. A data handling of GC/MS signals based on Experimental Autocovariance Function (EACVF) is described in order to directly characterize PAHs with a simple and reliable method suitable for processing large batches of samples. The method was successfully applied to 42 aerosol samples collected in different seasons (summer, fall and winter) in two locations in Northern Italy: Milan, a large urban area, and Oasi Le Bine, a rural site. The reliability of the EACVF results was verified by comparison with the values computed with the conventional GC/MS signal treatment and the data of independent studies. Two main emission sources were identified and described by PAH concentration profiles: the road traffic source (TR), characterized by high contributions of FLNT, PYR and CHR, and the residential combustion (COMB) mainly containing pyrogenic high molecular weight PAHs, i.e., CHR, BaP, BeP, BbF and BkF. In addition, some PAH diagnostic ratios were directly computed for the EACVF plot, to distinguish between traffic and combustion dominated emissions, i.e. the ratios CHR/BaP, PYR/BaP and PYR/BeP.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Itália , Reprodutibilidade dos Testes
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