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1.
Phys Chem Chem Phys ; 22(10): 5915-5919, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32108834

RESUMO

There is great interest in developing surfaces with enhanced properties for the sliding of liquid droplets. Here we show that both water and oil droplets placed on mesoporous thin film surfaces slide at relatively small tilt angles with respect to non-porous surfaces of the same material. The effect arises from a particular soft pinning at the contact line, which is a consequence of the fact that sessile droplets are partially "floating" onto a locally self-imbibed mesoporous film. Therefore, droplets present a reduced sliding angle and an enhanced sliding velocity in comparison to droplets on non-porous surfaces of the same material. The formed droplet-substrate interface is different to those observed on superhydrophobic or oil-infused surfaces, and involves a particular sliding dynamic. These findings would help to improve technical developments that require the precise handling of droplet mobility, whose interest span from chemical and biological assays in open microfluidic platforms to applications in energy and the environment.

2.
Analyst ; 141(13): 4235-4236, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27257633

RESUMO

Correction for 'Mesoporous titania thin films as efficient enzyme carriers for paraoxon determination/detoxification: effects of enzyme binding and pore hierarchy on the biocatalyst activity and reusability' by N. Francicet al., Analyst, 2014, 139, 3127-3136.

3.
Analyst ; 139(12): 3127-36, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24791279

RESUMO

In this work we demonstrate the efficient immobilization of histidine 6-tagged organophosphate hydrolase (His6-OPH), an organophosphate-degrading enzyme, on mesoporous titania thin films. This permits the use of the biocatalyst films as efficient tools in the detection/detoxification of paraoxon. His6-OPH was immobilized on mesoporous thin films with uniform (9 nm) and bimodal (13-38 nm) pore size distribution, through covalent attachment and physical adsorption. The biocatalyst films show good activity, and enhanced stability with respect to the free enzyme at extreme conditions of pH and temperature, especially around neutral pH and room temperature. In addition, the bioactive films can be easily separated from the reaction media and reused multiple times without significant loss of activity.


Assuntos
Enzimas/química , Paraoxon/análise , Titânio/química , Biocatálise , Paraoxon/toxicidade , Porosidade
5.
Epidemiol Prev ; 35(5-6 Suppl 4): 20-3, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-22166293

RESUMO

The concept of "polluted site" was firstly introduced in Italy with the definition of "environmental high risk areas" (Rule 349/86). Later, the decree 471/99 stated that a site is considered polluted if the concentration of even just one index pollutant in anyone of the matrices (soil or subsoil, surface or ground waters) exceeds the allowable threshold limit concentration. The boundaries of Italian polluted sites (IPS) were defined (Decree 152/06) on the basis of health, environmental and social criteria. SENTIERI Project includes 44 out of the 57 sites comprised in the "National environmental remediation program"; they correspond to the largest national industrial agglomerates. For each site, characterization data were collected, classified and arranged in tables. A great part of collected data came also from the environmental remediation programmes planned for the sites. These plans show that characterization and risk assessment activities were mainly undertaken for private industrial areas, as they were considered source of pollution. On the other hand, municipal and/or green and agricultural areas included in IPSs were poorly studied. Therefore, it is difficult to assess the exposure of the populations living inside and/or near the IPSs. The most probable population exposure come from the contamination of ground waters utilized for irrigation, or industrial emissions. For a description of SENTIERI, refer to the 2010 Supplement of Epidemiology & Prevention devoted to SENTIERI Project.


Assuntos
Poluição Ambiental , Substâncias Perigosas , Resíduos Perigosos , Resíduos Industriais , Vigilância da População , Exposição Ambiental , Poluição Ambiental/efeitos adversos , Poluição Ambiental/estatística & dados numéricos , Substâncias Perigosas/efeitos adversos , Resíduos Perigosos/efeitos adversos , Resíduos Perigosos/estatística & dados numéricos , Humanos , Resíduos Industriais/efeitos adversos , Resíduos Industriais/estatística & dados numéricos , Itália/epidemiologia , Concentração Máxima Permitida , Mortalidade , Medição de Risco , Poluição da Água/efeitos adversos , Poluição da Água/estatística & dados numéricos
7.
RSC Adv ; 8(12): 6414-6418, 2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35540379

RESUMO

Designing and controlling spontaneous imbibition is becoming a key requirement for advanced devices, presenting a substantial scientific and engineering challenge. Here we describe an approach that allows directional imbibition into designed geometries. A set of custom domains based on paper microfluidics mold nano-imbibition in user-defined shapes such as curvatures, corners, and vertices into mesoporous thin films; enabling localized chemical reactions with programmable designs. The method also achieves nano-size filtration, allows the generation and delivery of reagent gradients in a nanofluidic fashion, and it can be used as a reactor for the synthesis of patterned metallic nanoparticle arrays. By using this easy-to-build hybrid platform, users can create functional nanofluidic domains in custom geometries and perform spatially shaped chemistry. The ability to integrate mesoporous nanofluidic generation and paper-based microfluidics has made the hybrid system an exciting candidate for versatile nanoflow applications.

8.
Nanoscale ; 10(7): 3144-3147, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29383366

RESUMO

Exploiting natural phenomena is a central route for providing electricity to sustainably drive wearable electronics. Here we report a nano-scale water-driven energy generator that produces tiny electrical currents from spontaneous wetting-drying oscillations in mesoporous thin films. The system was fabricated with a wormlike mesoporous silica film, which was packed in between Cu and silicon contacts. The nanogenerator runs autonomously when a water droplet is laid over the film close to the Cu electrode, as water infiltration into the film under the electrode produces a direct-current. Wetting-drying cycles, which are spontaneously triggered by water evaporation, are perfectly correlated to the generated electrical current. The autonomous water displacement through the film yields a sustained energy conversion until the droplet reservoir vanishes. This novel water-driven nanogenerator opens new alternatives for versatile, mobile and cost-effective self-powering of nanosystems and nanodevices.

9.
Ann Ist Super Sanita ; 37(2): 301-7, 2001.
Artigo em Italiano | MEDLINE | ID: mdl-11758289

RESUMO

It is known that presently in Italy about 78% of generated urban waste solids get deposited in waste dumpsites. As of today, there is little known knowledge regarding the quality of the ambient surrounding dumpsites. Therefore it has become extremely important to understand the "risk factors" associated with a dumpsite. Through recent studies carried out mostly in the USA, there is evidence of widespread presence of vinyl chloride monomer (VCM) in the environment in proximity of industrial as well as urban dumpsites. The following is a summary of the most significant study reports with respect to the above. From an estimate based on study results, it is estimated that waste dumpsites in the USA emit altogether between 60 and 33,000 tons/year of vinyl chloride monomer into the atmosphere and ground water. Consequently these studies have shown the necessity to include vinyl chloride monomer amongst the monitoring parameters at waste dumpsites both during the operational phase, as well as during the post mortem phase.


Assuntos
Eliminação de Resíduos , Cloreto de Vinil/análise , Itália , Saúde da População Urbana
13.
Ann Emerg Med ; 35(3): 272-6, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10692195

RESUMO

STUDY OBJECTIVE: To assess patient knowledge of managed care organization (MCO) regulations, availability of alternative ambulatory care, and patient outcome after MCO insurance authorization denial for an emergency department visit. METHODS: A medical screening examination and a follow-up structured interview were conducted with patients denied authorization for ED visits. The study was conducted at a large urban hospital with 36,000 annual ED visits and 40% MCO patients. RESULTS: During a 7-month period, 151 patients did not receive MCO authorization for ED care. The interview response rate was 75% (104/138) with 13 patients excluded. Eighty-three percent (86/104) of respondents came to the ED because they believed their problem was an emergency. Four percent (4/104) of the respondents had been instructed to go to the ED but were later denied authorization, whereas 85.6% (89/104) did not know that the MCO could deny payment. Only 37% (38/104) of the respondents reported having received instruction on the MCO preauthorization process, whereas of the 19% who contacted their MCO as instructed, all resulted in scheduling difficulties. Although 57% (59/104) received follow-up within 24 hours, 11% (11/104) of the respondents had a subsequent return visit to the ED with a subsequent admission rate of 4% (4/104). CONCLUSION: Few patients are aware of the need for MCO preauthorization for ED care, and almost half do not receive alternative care within 24 hours. A significant number of patients (11%) returned to the ED with an admission rate of 4%.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Programas de Assistência Gerenciada/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial/estatística & dados numéricos , Criança , Pré-Escolar , Serviço Hospitalar de Emergência/economia , Feminino , Hospitais Urbanos , Humanos , Lactente , Recém-Nascido , Reembolso de Seguro de Saúde/economia , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Política Organizacional , Recusa do Paciente ao Tratamento
14.
Br J Ind Med ; 35(2): 161-7, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-656341

RESUMO

The salient features of this method for biological monitoring of occupational exposure to organophosphorus insecticides are: (a) acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) are determined separately in whole haemolysed blood using specific substrates at appropriate concentrations; (b) 20 microliter of blood drawn from the finger tip is sufficient for both determinations; (c) the blood sample is immediately diluted with a solution of saponin and may thereafter be frozen for storage; (d) diagnostic kits, commercially available for the determination of plasma BuChE, may be employed with modifications; (e) the kinetic procedure is avoided by blocking the enzyme reactions at the end of the incubation period. This paper describes attempts to achieve optimal conditions for the two reactions. Under the conditions finally chosen, the whole blood 'AChE' activity value still includes a small percentage of plasma BuChE activity (12.5% of the total), while the whole blood 'BuChE' activity includes a small percentage of erythrocyte AChE activity (7% of the total). Results of determinations performed with this procedure on 172 healthy subjects are reported.


Assuntos
Acetilcolinesterase/sangue , Butirilcolinesterase/sangue , Colinesterases/sangue , Adolescente , Adulto , Inibidores da Colinesterase , Exposição Ambiental , Feminino , Humanos , Inseticidas , Masculino , Métodos , Pessoa de Meia-Idade , Compostos Organofosforados , Fisostigmina/farmacologia , Dodecilsulfato de Sódio/farmacologia
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