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31.
Visnja Krizanovic Cik Drago Zagar Kresimir Grgic 《Universal Access in the Information Society》2018,17(3):517-540
Broadband solutions, i.e., broadband technologies and services, offer users numerous benefits. However, inequalities related to the levels of broadband solutions’ deployment and adoption between rural and urban areas, i.e., the digital divide, remain a consequential problem worldwide. To reduce the digital divide, the issues related to the deployment and usage of broadband solutions in rural areas are analysed in this paper. To define optimal strategies for the deployment and adoption of rural broadband solutions, the application of an extended techno-economic assessment process is considered. Therefore, an additional framework that extends the structure of standard techno-economic models is proposed, and its detailed overview is given. Within the framework, the regression analyses of factors relevant to broadband solutions deployment and adoption in rural areas are defined. The results of conducted analyses are used in the standard techno-economic modelling process. Finally, the efficiency of framework usage in techno-economic assessment process and in finding optimal broadband solutions is demonstrated for a case study rural scenario. 相似文献
32.
Apostoli P Cortesi I Mangili A Elia G Drago I Gagliardi T Soleo L Valente T Sciarra GF Aprea C Ronchi A Minoia C 《The Science of the total environment》2002,289(1-3):13-24
The results of a polycentric study to assess the reference values of urinary mercury (U-Hg) in four Italian cities are presented. A total of 383 subjects were selected on the basis of standardised criteria by a questionnaire on personal habits, lifestyle, occupational or non-occupational exposure to Hg, medical history, number and area of dental amalgams. U-Hg was determined by hydride generation atomic absorption method (HG-AAS), with a detection limit of 0.5 microg/l and by flow injection (FI) inductively coupled plasma mass spectrometry (ICP-MS), with a detection limit of 0.03 microg/l. The median value of U-Hg, determined by HG-AAS, was 0.78 microg/g creatinine (0.75 for males and 0.83 for females), with 5 degrees and 95 degrees percentiles, respectively, of 0.17 and 3.66 microg/g creatinine. When determined by FI ICP-MS, the median value was 0.79 microg/g creatinine (0.77 for males and 0.79 for females) with 5 degrees and 95 degrees percentiles of, respectively, 0.12 and 5.02 microg/g creatinine. Among the independent variables, city of origin, area of dental amalgams, fish intake and tobacco smoking significantly influenced the U-Hg levels. The U-Hg reference values from this survey are lower than those from other recent investigations, probably due to characteristics and selection of the examined individuals and to the strict control of pre-analytical and analytical factors of variability. 相似文献
33.
Lucia Montenegro Claudia Carbone Gabriele Condorelli Rossella Drago Giovanni Puglisi 《Drug development and industrial pharmacy》2013,39(5):539-548
ABSTRACTIn this work we investigated the effects of oil phase lipophilicity on in vitro drug release from topical o/w microemulsions (MEs) containing low percentages of emulsifiers. Three different lipids, isopropyl myristate (IPM), isopropyl palmitate (IPP), and isopropyl stearate (IPS), whose lipophilicity increased in the order IPM < IPP <IPS, were used as oil phase to prepare o/w MEs containing low amounts (7.7% w/w) of two surfactant/cosurfactant mixtures, isoceteth-20/glyceryl oleate (5:2) (MEs 1–3) and oleth-20/glyceryl oleate (5:2) (MEs 4–6). All the MEs were prepared using the phase inversion temperature (PIT) method.Three active compounds (0.5% w/w), Naproxen (NAP), Idebenone (IDE), and Butylmethoxydibenzoylmethane (BMBM), were selected as model drugs and their release rates from PIT MEs were evaluated using Franz-type diffusion cells. All the MEs gave a mean droplet diameter ranging from 28 to 44 nm and showed a single peak in size distribution. The addition of IDE to MEs 1–6 did not significantly change ME droplet size. On the contrary, an increase of the droplet size beyond the ME limit (150 nm) was observed when isoceteth-20 was used as surfactant to prepare MEs containing NAP or MEs containing BMBM and IPS as oil phase. Pseudo-first order release rates were observed only for NAP from MEs 1–3, while MEs containing IDE showed an initial slow release followed by an increased release of the test compound. The release rate constants were found to be dependent on the ME composition and on the active compound incorporated. The highest release rate was observed from ME 1 containing IPM as oil phase and NAP as drug. As regards BMBM, its release rate was not calculated since no release was observed until 6 h from the beginning of the experiment. The cumulative amount of active compound released after 22 h was inversely related to drug lipophilicity (NAP Log P = 2,9; IDE Log P 3,5; BMBM Log P 4,8). These findings could be attributable to a reduced thermodynamic activity of the drugs in the vehicles containing the most lipophilic oil phase due to an increase of drug solubility which could lead to an unfavorable drug partition from the oil phase. The results of this study suggest that the choice of proper combinations of oil phase lipids and emulsifiers may allow achieving drug controlled delivery from topical o/w MEs with low emulsifier content. 相似文献
34.
35.
Silvia Ruggieri Valeria Longo Cinzia Perrino Silvia Canepari Gaspare Drago Luca LAbbate Martin Balzan Giuseppina Cuttitta Gianluca Scaccianoce Remo Minardi Giovanni Viegi Fabio Cibella 《Indoor air》2019,29(2):276-290
This study aimed at surveying lower secondary schools in southern Italy, in a highly polluted area. A community close to an industrial area and three villages in rural areas was investigated. Indoor temperature, relative humidity (RH), gaseous pollutants (CO2 and NO2), selected biological pollutants in indoor dust, and the indoor/outdoor mass concentration and elemental composition of PM2.5 were ascertained. Temperature and RH were within, or close to, the comfort range, while CO2 frequently exceeded the threshold of 1000 ppm, indicating inadequate air exchange rate. In all the classrooms, median NO2 levels were above the WHO threshold value. Dermatophagoides p. allergen concentration was below the sensitizing threshold, while high endotoxin levels were detected in the classrooms, suggesting schools may produce significant risks of endotoxin exposure. Concentration and solubility of PM2.5 elements were used to identify the sources of indoor particles. Indoor concentration of most elements was higher than outdoors. Resuspension was responsible for the indoor increase in soil components. For elements from industrial emission (Cd, Co, Ni, Pb, Sb, Tl, V), the indoor concentration depended on penetration from the outside. For these elements, differences in rural vs industrial concentrations were found, suggesting industrial sources may influence indoor air quality nearby schools. 相似文献
36.
37.
F Drago E Ranieri A Pastorino S Casazza F Crovato A Rebora 《Canadian Metallurgical Quarterly》1996,134(1):170-174
Cutaneous lesions related to chronic active Epstein-Barr virus (EBV) infection have been rarely documented in immunocompetent patients. A 30-year-old woman, fulfilling the diagnostic criteria for the chronic fatigue syndrome, had a 10-year history of pruritic brownish macules and papules on her chest and back. Her EBV serology was abnormal; the EBV genome was present in the epidermis of lesions, in oral secretions, and in peripheral mononuclear cells (PMC). Her blood lymphocytes spontaneously outgrew in culture. Histology revealed deposits of amyloid in the papillary dermis. Treatment with acyclovir and interferon-alpha rapidly improved her condition, stopped the lymphocyte outgrowth in culture, and reduced the EBV DNA content in oral secretions and in PMC. These data support an endogenous reactivation of EBV infection and suggest a causal relationship with primary amyloidosis. 相似文献
38.
Effects of heating and 60cobalt (60Co) irradiation to hepatitis C virus (HCV) RNA in sera were studied. HCV-RNA can not be detected by PCR in 10 positive serum samples after being heated at 56 degrees C for 10 hours. Whereas, HCV-RNA can still be detected in positive sera after being lyophilized and then heated at 60 degrees C for 20 hours. It suggested heating at 56 degrees C for 10 hours can inactivate HCV in sera and the sera should be in liquid status when thermal inactivation is taken. Lyophilized sera with thermal inactivation for HCV should be inactivated first and then lyophilized. But the safety of sera with heat-treatment should be further investigated. Inactivation of HCV in sera with 60Co irradiation needed extra large dose of it, and protein components in sera would obviously be altered. Therefore, inactivation of HCV in sera with 60Co irradiation is impractical. 相似文献
39.
F Drago E Ranieri F Malaguti ML Battifoglio E Losi A Rebora 《Canadian Metallurgical Quarterly》1997,195(4):374-378
BACKGROUND: Clinical evidence suggests a viral etiology for pityriasis rosea (PR). OBJECTIVE: To evaluate human herpesvirus (HHV)-6 and HHV-7 as candidates for the etiology of PR. METHODS: Blood and skin tissue from 12 patients with acute PR, and 12 patients with other dermatoses were studied, as well as blood samples from 25 healthy persons. Serum interferon (IFN)-alpha and IFN-gamma were analyzed by ELISA. Analysis of morphological changes in cocultured peripheral blood mononuclear cells (PBMC) and electron microscopy (EM) to identify viral particles were performed. Polymerase chain reaction (PCR) with specific primers for HHV-6 and HHV-7 DNA sequences was performed on the plasma and PBMC of patients and healthy controls and on the skin of patients with PR and other skin diseases. RESULTS: PR plasma contained detectable IFN-alpha and IFN-gamma, whereas plasma from controls did not. PBMC from PR patients showed ballooning cells and syncytia after 7 days in culture whereas PBMC from controls and recovered PR patients did not. This cytopathic effect was also documented in a PR patient who relapsed and in Sup-T1 cell cultures inoculated with the cell-free supernatant from centrifuged cultured PBMC; in this supernatant, herpesvirus, virions were detected by EM, PCR identified HHV-7 DNA in PBMC, plasma and skin from all patients with active PR and in the PBMC only of 5 patients tested 10-14 months later. Weaker signals of HHV-7 DNA were detected in PBMC of 11 controls, but not in their plasma. Skin was negative for HHV-7 in all control specimens. CONCLUSIONS: Although the detection of HHV-7 DNA in PBMC and tissues does not prove directly a causal role, HHV-7 DNA in cell-free plasma corresponds to active replication which supports a causal relationship. We propose that PR is a clinical presentation of HHV-7 reactivation. 相似文献
40.