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1.
Chemosphere ; 297: 133986, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35176299

RESUMEN

To date, the introduction of biodegradable plastics such as PLA in anaerobic digestion systems has been limited by a very low rate of biodegradation. To overcome these limitations, pretreatment technologies can be applied. In this study, the impact of pretreatments (mechanical, thermal, thermo-acid, and thermo-alkaline) was investigated. Mechanical pretreatment of PLA improved its biodegradation rate but did not affect the ultimate methane potential (430-461 NL CH4 kg-1 VS). In parallel, thermal and thermo-acid pretreatments exhibited a similar trend for PLA solubilization. Both of these pretreatments only achieved substantial solubilization (>60%) at higher temperatures (120 and 150 °C). At lower temperatures (70 and 90 °C), negligible solubilization (between 1 and 6%) occurred after 48 h. By contrast, coupling of thermal and alkaline pretreatment significantly increased solubilization at the lower temperatures (70 and 90 °C). In terms of biodegradation, thermo-alkaline pretreatment (with 5% w/v Ca(OH)2) of PLA resulted in a similar methane potential (from 325 to 390 NL CH4 kg-1 VS) for 1 h at 150 °C, 6 h at 120 °C, 24 h at 90 °C, and 48 h at 70 °C. Reduction of the Ca(OH)2 concentration (from 5% to 0.5% w/v) highlighted that a concentration of 2.5% w/v was sufficient to achieve a substantial level of biodegradation. Pretreatment at 70 and 90 °C using 2.5% w/v Ca(OH)2 for 48 h resulted in biodegradation yields of 73% and 68%, respectively. Finally, a good correlation (R2 = 0.90) was found between the PLA solubilization and its biodegradation.


Asunto(s)
Metano , Poliésteres , Anaerobiosis , Biodegradación Ambiental , Metano/metabolismo , Poliésteres/metabolismo , Aguas del Alcantarillado
2.
Sci Rep ; 11(1): 16984, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34417519

RESUMEN

For workplaces where significant diurnal variations in radon concentrations are likely, measurements to evaluate average radon concentration during working hours could be useful for planning an optimized protection of workers according to the 2013/59/Euratom Directive. However, very few studies on this subject, generally limited to periods of few weeks, have been published. Therefore, a study has been conducted to evaluate the actual long-term radon exposure during working hours for a sample of 33 workplaces of four different types (postal offices, shops, restaurants, municipal offices), mainly located at the ground floor, and with expected considerable air exchange rate occurring during working hours due to frequent entrance/exit of persons or mechanical ventilation. The results show that the difference between the average radon level during working hours and that one during the whole day is about 20% on average and ranges from 0 to 50%. These observed differences, generally smaller compared with those found in other similar studies, are nearly the same if the analysis is restricted to workplaces with annual radon level higher than 300 Bq m-3, and therefore natural or mechanical ventilation normally present during working hours of the monitored workplaces cannot be considered an effective mitigation measure. However, the costs and time-response characteristics of the active monitors, as those used for the present study, will probably allow using more frequently a similar measurement strategy in workplaces.

3.
J Environ Radioact ; 225: 106438, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33017779

RESUMEN

In this paper the authors present a collection of radon emanation and exhalation rate data of about 2000 samples of building materials used in Europe. The data analysis highlighted some critical issues, such as the use of different units to express radon exhalation rate, the use of different measurement techniques and the general lack of information about density and thickness of samples. In many cases these differences of type and amount of information make difficult a reliable comparison of the obtained data. In the light of these considerations, the need arises to start, at both national and European level, a research activity aimed to develop a shared protocol for measuring the radon exhalation rate based on widely used and reliable measurement techniques. At European level, this protocol could support in forthcoming EU Member States national radon action plans, to take into account the contribution of building materials to the indoor radon concentrations.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Monitoreo de Radiación , Radón/análisis , Materiales de Construcción , Europa (Continente) , Espiración
4.
Ann Ig ; 31(6): 576-581, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31616901

RESUMEN

The WHO Global Action Plan on physical activity underlines the binomial "diet and physical activity" for the maintenance of well-being state. The adequate nutritional intake is required for sport and can be achieved by a well-adjusted diet without adding artificial food supplements, whose abuse can even represent a risk and appear as an antechamber of doping. Within a national doping prevention project, a peer education tool was realized in the form of a book and e-book, based on the principle of the Mediterranean Diet as an effective nutritional support in sport and physical activity. This health-literacy book contains recipes from all Italian regions revised for their capability to satisfy sport nutritional needs.


Asunto(s)
Atletas , Dieta Mediterránea , Ejercicio Físico/fisiología , Educación en Salud/métodos , Libros , Libros de Cocina como Asunto , Dieta , Suplementos Dietéticos , Doping en los Deportes/prevención & control , Humanos , Italia , Grupo Paritario
5.
J Environ Radioact ; 187: 90-105, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29429872

RESUMEN

The paper presents the latest collection of activity concentration data of natural radionuclides (226Ra, 232Th and 4 K) in building materials. This database contains about 24200 samples of both bulk materials and their constituents (bricks, concrete, cement, aggregates) and superficial materials used in most European Union Member States and some European countries. This collection also includes radiological information about some NORM residues and by-products (by-product gypsum, metallurgical slags, fly and bottom ashes and red mud) which can be of radiological concern if recycled in building materials as secondary raw materials. Moreover, radon emanation and radon exhalation rate data are reported for bricks and concrete.


Asunto(s)
Radiación de Fondo , Materiales de Construcción/análisis , Monitoreo de Radiación , Radiactividad , Europa (Continente) , Radio (Elemento)/análisis , Radón/análisis , Torio/análisis
6.
Radiat Prot Dosimetry ; 177(1-2): 12-15, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29036725

RESUMEN

The recently developed radon film-badge makes it possible to measure radon indoors, in soil, in water and/or in aqueous media (e.g. mud). As a result of its wide response linearity, this monitor has been successfully used to measure radon in-water with concentrations from 10 to ~10 000 Bq/L. By exploiting the unique characteristics of this badge, a mini-survey has been carried out by Health Canada in which radon in water was measured from 12 private wells, as well as in tap water originating from the Ottawa River. Due to the widespread interest of different laboratories in using these passive monitors, laboratories were provided with plastic films to construct their own badges by using in-house CR-39 detectors. Monitors were then irradiated by a known radon concentration at the National Institute of Radiation Metrology (ENEA)'s radon chamber and sent back to each laboratory for processing and counting. Even though these laboratories have been using different etching- and counting-procedures, the film-badge responses varied only within ~12%.


Asunto(s)
Contaminación del Aire Interior/análisis , Dosimetría por Película , Cooperación Internacional , Monitoreo de Radiación/métodos , Radón/análisis , Contaminantes Radiactivos del Agua/análisis , Canadá , Humanos
7.
J Environ Radioact ; 168: 54-60, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27426854

RESUMEN

Orvieto (Italy) has a large network of underground tunnels quarried to extract tuff and pozzolana by Etruscans and Romans. One of these tunnels was chosen as natural laboratory to compare different radiation measurement and dose assessment methods. Indeed, tuff and pozzolana are very rich in natural radioactivity and are interesting from the radiation protection point of view since they are still used as building materials. In order to characterize this site an in situ experimental procedure was followed. It consisted in measurements carried out with different instruments: two portable gamma ray spectrometers, two gamma dose rate meters, two radon monitors and one two channel working level monitor. Samples of tuff and pozzolana stones were also collected to be measured with gamma spectrometry in laboratory. Due to the high content of 238U, 232Th (more than 200 Bq kg-1 for both radionuclides) and 40K (more than 2000 Bq kg-1) of tuff and pozzolana, elevated levels of exposure to natural radioactivity were found: indeed, with different instruments and approach, a gamma dose rate of about 1 µGy h-1 and an average radon concentration of about 10,000 Bq m-3, with a Potential Alpha Energy Concentration (PAEC) of 288 MeV cm-3, were measured. The radiological characteristics of Orvieto underground quarry make it a perfect site for "in field" intercomparisons of different measurement and dose assessment methods.


Asunto(s)
Aerosoles/análisis , Materiales de Construcción/análisis , Monitoreo de Radiación , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Italia , Espectrometría gamma
9.
Appl Radiat Isot ; 102: 93-97, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26002275

RESUMEN

In the present study the robustness of the etching process used by our laboratory was assessed. The strategy followed was based on the procedure suggested by Youden. Critical factors for the process were estimated using both Lenth's method and Dong's algorithm. The robustness test evidences that particular attention needs to be paid to the control of the etching solution's temperature.

10.
Musculoskelet Surg ; 99(2): 127-32, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25904348

RESUMEN

BACKGROUND AND PURPOSE: Irreparable rotator cuff tears are a common cause of pain in adult population, requiring in many cases a surgical treatment. Possible alternatives are debridement, partial repair, muscle transfers and joint replacement. We evaluated two groups of patients with irreparable rotator cuff tear treated surgically: one group received an arthroscopic-assisted latissimus dorsi tendon transfer (LDTT), and the other an arthroscopic rotator cuff partial repair. Aim of our study was to compare clinical results and quality of life in two groups of patients with massive irreparable rotator cuff tear: one receiving an arthroscopic LDTT and the other receiving an arthroscopic rotator cuff partial repair. METHODS: Forty patients were assigned to two groups: 20 patients to group TT treated with LDTT and 20 patients to group PR treated with a partial repair. The average follow-up duration was 2.8 years (1-5, SD 3). Pre- and postoperative modified UCLA shoulder score, ROM, measurement of the strength and the rotator cuff quality of life (RC-QOL) were used to asses the outcome. RESULTS: LDTT showed significative improvements when compared to partial repair in UCLA score results, strength and RC-QOL questionnaire. No differences were found between the groups in pain relief. CONCLUSION: Both techniques are effective in reducing patients' symptoms. We believe that in younger, high-demanding patients with no or mild osteoarthritis, the LDTT represents a valid treatment option with better modified UCLA score improvement and strength at our follow-up.


Asunto(s)
Lesiones del Manguito de los Rotadores/cirugía , Músculos Superficiales de la Espalda/trasplante , Factores de Edad , Anciano , Artralgia/cirugía , Artroscopía/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Calidad de Vida , Rotura/cirugía , Transferencia Tendinosa/métodos , Factores de Tiempo , Resultado del Tratamiento
12.
Radiat Prot Dosimetry ; 162(1-2): 171-5, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25061128

RESUMEN

The inhalation of short-lived radon decay products (RDP) yields the greatest contribution to the natural radiation exposure. This paper deals with a study carried out to improve the knowledge of the behaviour of RDPs, their interaction with particulates and the plateout during the time. The tests confirmed that a high aerosol particle concentration increases the probability that an ion sticks to aerosol and remains long in the air, leading to both an increase of F and a decrease of fp, as reported in the literature. The same experimental protocol applied in a small radon chamber showed a strong reduction of the equilibrium factor (an average of ∼10 %), because in a small environment the plateout phenomenon prevails on the attachment to particulate.


Asunto(s)
Aerosoles/análisis , Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Material Particulado/análisis , Monitoreo de Radiación , Radón/análisis , Humanos
13.
Langmuir ; 29(43): 13198-208, 2013 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24073939

RESUMEN

Four thiolated oligoarylene molecules (i) 4-methoxy-terphenyl-4″-methanethiol (MTM), (ii) 4-methoxy-terphenyl-3″,5″-dimethanethiol (MTD), (iii) 4-nitro-terphenyl-4″-methanethiol (NTM), and (iv) 4-nitro-terphenyl-3″,5″-dimethanethiol (NTD) were synthesized and self-assembled as monolayers (SAMs) on polycrystalline Au electrodes of organic field-effect transistors (OFETs). SAMs were characterized by contact angle and AC/DC electrochemical measurements, whereas atomic force microscopy was used for imaging the pentacene films grown on the coated electrodes. The electrical properties of functionalized OFETs, the electrochemical SAMs features and the morphology of pentacene films were correlated to the molecular organization of the thiolated oligoarylenes on Au, as calculated by means of the density functional theory. This multi-methodological approach allows us to associate the systematic replacement of the SAM anchoring head group (viz. methanethiol and dimethanethiol) and/or terminal tail group (viz. nitro-, -NO2, and methoxy, -OCH3) with the change of the electrical features. The dimethanethiol head group endows SAMs with higher resistive features along with higher surface tensions compared with methanethiol. Furthermore, the different number of thiolated heads affects the kinetics of Au passivation as well as the pentacene morphology. On the other hand, the nitro group confers further distinctive properties, such as the positive shift of both threshold and critical voltages of OFETs with respect to the methoxy one. The latter experimental evidence arise from its electron-withdrawing capability, which has been verified by both DFT calculations and DC electrochemical measurements.

14.
J Mater Chem B ; 1(31): 3728-3741, 2013 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32261126

RESUMEN

There is a quest for electronic biosensors operated in water for biomedical applications and environmental monitoring. Water is an aggressive medium for standard electronics materials and devices due to its strong polarizability and electrochemical activity. Thick dielectric encapsulation provides necessary stability while it damps the sensitivity of the device to sensing events occurring in the aqueous environment. Organic electronics provides materials that exhibit stable electronic conduction in direct contact with water combined with other desirable properties like mechanical softness, biocompatibility and processability onto flexible substrates. In this review, we introduce an emerging class of organic transistors, in which the current across the organic film is gated by the electric field of the Debye-Helmholtz layer. We discuss the device physics, the sensing mechanism and the relevant electrochemical processes. Applications of water-gated transistors range from the sensing of biologically relevant molecules like DNA, proteins or hormones to non-invasive recording and stimulation of electrical activity of neurons. Materials chemistry is crucial to control properties of electrically active films and to allow the introduction of specific chemical functionalities and receptors at sensing interfaces of the device.

15.
Br J Cancer ; 104(9): 1372-6, 2011 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-21487407

RESUMEN

BACKGROUND: Trastuzumab has recently shown efficacy in the treatment of HER2-positive advanced gastric adenocarcinoma. Although antibody-based therapies target the metastatic disease, HER2 status is usually evaluated in the primary tumour because metastatic sites are rarely biopsied. The aim of this study was to compare HER2 status in primary and paired metastatic sites of gastric adenocarcinoma. METHODS: The HER2 status was assessed by fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) in 72 secondary lesions of gastric adenocarcinoma and in the corresponding primary tumours. RESULTS: Concordance of FISH results, evaluable in 68 primary and matched metastatic sites, was 98.5%. Concordance of IHC results, available in 39 of the 72 paired cases, was 94.9%. Only one case showed discordance between primary tumour and metastasis, being negative by both IHC and FISH in the primary and showing HER2 overexpression and amplification in the corresponding pancreatic lymph node metastasis. CONCLUSION: The high concordance observed between HER2 results obtained by both IHC and FISH on primary tumours and corresponding metastases suggests that in gastric cancer HER2 status is maintained in most cases unchanged during the metastatic process.


Asunto(s)
Adenocarcinoma/química , Adenocarcinoma/patología , Biomarcadores de Tumor/análisis , Inmunohistoquímica , Hibridación Fluorescente in Situ , Receptor ErbB-2/análisis , Neoplasias Gástricas/química , Neoplasias Gástricas/patología , Adenocarcinoma/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antineoplásicos/uso terapéutico , Líquido Ascítico/química , Ensayos Clínicos como Asunto , Unión Esofagogástrica , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/química , Neoplasias Hepáticas/secundario , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/química , Neoplasias Peritoneales/secundario , Derrame Pleural Maligno/química , Neoplasias Cutáneas/química , Neoplasias Cutáneas/secundario , Neoplasias Gástricas/tratamiento farmacológico , Trastuzumab , Regulación hacia Arriba
16.
J Radiol Prot ; 30(2): 149-59, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20530856

RESUMEN

Etched track detectors are widely used for the detection of radon and its decay products. The reliability of radon measurement performed with such devices requires that laboratories producing analytical data are able to provide results of the required quality. The need for uniform results from laboratories at an international level therefore requires the implementation of a quality assurance programme, the harmonization of criteria, sampling procedures, calculations and the reporting of results, agreed on the basis of fundamental principles and international standards. The quality assurance programme described here is the first step on the way to ISO/IEC 17025 certification for the RI-RN (ISPESL) laboratory.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Guías como Asunto , Garantía de la Calidad de Atención de Salud/organización & administración , Monitoreo de Radiación/normas , Radón/análisis , Italia , Dosis de Radiación
18.
Res Vet Sci ; 85(1): 141-4, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17961616

RESUMEN

Cardiac Troponin I (cTnI) is a polypeptide involved in myocardial contraction and has been shown to be a highly sensitive biomarker of myocardial injury in humans. Chronic myocardial ischemia was induced in eight adult sheep by anterior coronary artery legation. Forty-five days after coronary artery legation, sheep underwent autologous myoblasts implantation to the infarct area to improve local tissue regeneration. Blood samples were taken at regular intervals before and after the induced coronary ischemia and myoblast implantation and serum levels of cTnI were assessed with chemiluminescent immunodosage using a commercially available anti-human cTnI monoclonal antibody. cTnI levels began to increase the day after coronary legation and after myoblast implantation and gradually recovered to physiological levels in the next 14 days. Furthermore, the commercial anti-human antibody was shown to completely cross react with the ovine polypeptide as well as with canine, swine and equine sera.


Asunto(s)
Isquemia Miocárdica/sangre , Troponina I/sangre , Animales , Trasplante de Células , Modelos Animales de Enfermedad , Femenino , Mioblastos Cardíacos , Ovinos , Factores de Tiempo
19.
Hip Int ; 17(4): 234-6, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-19197874

RESUMEN

Vascular lesions in hip prosthetic replacement are rare events; it is mandatory to be aware of the risk, though, in order of the vascular bundle's proximity to the surgical field. A 74-year-old patient was admitted to our department for primary hip arthroplasty for osteoarthritis. The patient was healthy but had mild hypertension. A cemented total hip prosthesis was implanted. The patient complained of growing groin pain and swelling from the third postoperative day. The suspicion of a vascular injury arose with worsening pain and low haemoglobin at blood tests. Then ultrasonography scans and digital angiography were performed, showing a superficial femoral artery pseudo-aneurysm. The patient had further surgery to repair the lesion. In the described case, the pseudo-aneurysm might have been caused by the pulling of a Hohmann retractor on arterial vessels possibly affected by atherosclerosis. The final output was favourable, but the authors point out that knowledge of neurovascular anatomy is necessary as well as postoperative surveillance of the clinical presentation of the patient if groin pain or swelling should arise. In the case of suspicion of vascular lesions, ultrasound and angiography will allow diagnosis and confirm the indication for surgical repair.

20.
Mini Rev Med Chem ; 6(11): 1201-11, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17100631

RESUMEN

This review summarizes the knowledge of the role of dietary PUFAs, especially omega-3, on normal brain function. Furthermore, it reports the evidence pointing to potential mechanisms of omega-3 fatty acids in development of neurological disorders and efficacy of their supplementation in terms of symptom management.


Asunto(s)
Ácidos Grasos Insaturados/deficiencia , Ácidos Grasos Insaturados/metabolismo , Enfermedades del Sistema Nervioso/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Progresión de la Enfermedad , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Humanos , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/patología , Enfermedades del Sistema Nervioso/patología
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