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141.
By using short‐circuited Composite Right/Left‐Handed Transmission Lines as loading stubs, and Purely Right‐Handed Artificial Transmission Lines, a Dual‐Band Branch‐Line coupler is presented. The adoption of such technologies adds degrees of freedom with respect to other already proposed design techniques, thus allowing the development of a very compact device, and a larger flexibility in the choice of the two operating frequencies and corresponding bandwidths. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. 相似文献
142.
Molecular analysis of poliovirus 3 isolated from an aerosol generated by a waste water treatment plant 总被引:1,自引:0,他引:1
Michele Muscillo Giuseppina La Rosa Annalaura Carducci Laura Cantiani Cinzia Marianelli 《Water research》1997,31(12):3125-3131
We examined three samples of lysates from cell cultures that had previously been infected by the aerosol generated by a waste water treatment plant near Pisa. We first attempted to confirm that we were dealing with one of the enterovirus family, using an inverse PCR analysis of the RNA extracted from the cell lysates. This identified a single genome sequences in all the samples, which corresponded to poliovirus 3. Sequence analyses revealed that the genotyping of poliovirus 3 was accurate for the species, irrespective of the genomic region sequenced. Subspecies genotyping is only possible for the translated region, and in this case, it identified the Poliovirus type 3 Leon 12a1b strain as ancestor of the virus isolated. Molecular analyses were then carried out on the wild virus in the regions VP2 (9623 bp), VP3 (922 bp) and VP1 (1128 bp) and found various nucleotide mutations (e.g. 472T→C; 970G→C, Cys→Ser; 1319G→T, Val→Leu; 1743T→C, Val→Ala; 1817C→T, Hys→Tyr). Thermosensitivity tests at 34°C and 44°C showed a slight reversion to the heat resistant phenotype. The need for adequate protective measures for plant staff, together with the frequent use of treated water for irrigation, means that effective methods of aerosol borne pathogen detection and risk determination must be adopted. 相似文献
143.
144.
Pyridine adsorption reveals high-coordinated cationic centres at the surface of microcrystalline ZnO
The adsorption of pyridine at 300 K on microcrystalline ZnO has been investigated by FTIR spectroscopy. Besides an interaction by H-bonding with surface OH groups, evidence is found for the Lewis coordination of pyridine onto coordinatively unsaturated surface Zn2+ centres possessing a regular tetrahedral coordination, as well as onto some other surface Zn2+ centres, only slightly uncoordinated. The creation at the surface of the ZnO of cationic centres with an anomalous coordination higher than 4 (quasi-octahedral) is thus postulated. No such high-coordinated Zn2+ centres seem to form to an appreciable extent when ZnO is dispersed (at least at up to a 3% weight level) at the surface of other microcrystalline oxides such as, for instance, TiO2. 相似文献
145.
Luigino Calzetta Marina Aiello Annalisa Frizzelli Giuseppina Bertorelli Paola Rogliani Alfredo Chetta 《International journal of molecular sciences》2021,22(13)
Airway inflammation represents an important characteristic in asthma, modulating airflow limitation and symptom control, and triggering the risk of asthma exacerbation. Thus, although corticosteroids represent the cornerstone for the treatment of asthma, severe patients may be dependent on oral corticosteroids (OCSs). Fortunately, the current humanised monoclonal antibodies (mAbs) benralizumab, dupilumab, mepolizumab, omalizumab, and reslizumab have been proven to induce an OCS-sparing effect in randomized controlled trials (RCTs), thus overcoming the problem of OCS dependence in severe asthma. Nevertheless, a large discrepancy has been recognized between selected patients enrolled in RCTs and non-selected asthmatic populations in real-world settings. It is not possible to exclude that the OCS-sparing effect of mAbs resulting from the RCTs could be different than the real effect resulting in clinical practice. Therefore, we performed a systematic review and correlation analysis to assess whether mAbs are effective in eliciting an OCS-sparing effect and overcoming the OCS dependence in severe asthmatic patients in real-world settings. Overall, real-world studies support the evidence that OCS dependence is a real condition that, however, can be found only in a small number of really severe asthmatic patients. In most patients, the dependence on OCS can be related to modifying factors that, when adequately modulated, may lead to a significant reduction or suspension of OCS maintenance. Conversely, in severe asthmatics in whom OCS resistance is proved by a high daily dose intake, mAbs allow reversion of the OCS dependence, leading to the suspension of OCS therapy in most patients or >50% reduction in the daily OCS dose. 相似文献
146.
Annabella Di Mauro Giosu Scognamiglio Gabriella Aquino Margherita Cerrone Giuseppina Liguori Ottavia Clemente Maurizio Di Bonito Monica Cantile Gerardo Botti Salvatore Tafuto Fabiana Tatangelo 《International journal of molecular sciences》2021,22(13)
Gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) are rare diseases occurring in the gastrointestinal tract and pancreas. They are characterized by the loss of epithelial tubular gland elements, and by the increased expression of neuroendocrine markers. GEP-NENs are subdivided into two histo-pathological types, gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs) and gastro-entero-pancreatic neuroendocrine carcinomas (GEP-NECs). According to WHO 2017 and 2019 classification criteria are graded and staged in four categories, NET-G1, NET-G2, NET-G3, and NEC-G3. The molecular characterization of these tumors can be fundamental for the identification of new diagnostic, prognostic and predictive biomarkers. The main purpose of this study was to analyze the expression of the paralogous 13 HOX genes, normally involved in embryogenic development and frequently deregulated in human cancers, and of the HOX regulating lncRNA HOTAIR in GEP-NENs. The expression of HOX genes is gradually lost in the transition from GEP NET G1 to NET/NEC G3 tumors, while HOTAIR expression, inversely correlated with HOX genes expression and weakly expressed in low-grade GEP NENs, becomes aberrant in NET G3 and NEC G3 categories. Our data highlights their potential role in the molecular stratification of GEP-NENs by suggesting new prognostic markers and potential therapeutic targets. 相似文献
147.
Laura Gozzelino Bruno Minetti Roberto Gerbaldo Gianluca Ghigo Francesco Laviano Giuseppina Lopardo Carmen Plapcianu Angelo Agostino Stefano Cagliero Marco Truccato Luca Zilberti Enrica Mezzetti 《Journal of Superconductivity and Novel Magnetism》2011,24(1-2):307-312
Magnetic shielding properties of MgB2 bulk samples synthesized by the SPS (Spark?CPlasma?CSintering) technique were characterized in low applied magnetic fields at temperatures ranging from 20 to 37 K. The used growth technique allows one to produce this compound in different shapes and sizes required for shielding applications. In this framework, shielding magnetic-induction field profiles generated by MgB2-based shield components, shaped as planar thick disks, were measured by means of a suitable Hall probe in-plane array. The magnetic field distribution at different vertical distances above the sample was also obtained by a micrometric motion of the probe ensemble. Magnetic field profiles were then analyzed in the framework of the critical state model and the critical current density, J c , was evaluated. The J c magnitude indicates that the material under test is a good candidate for passive magnetic shield manufacturing up to temperatures close to the transition one. 相似文献
148.
Considering its widespread distribution in marine environments, its fast replication times and low infectious doses and the rapid spread of its strains in recent years, intensive and continuous monitoring of potentially pathogenic Vibrio parahaemolyticus is strongly recommended in order to assess the human health risk arising from shellfish consumption. The lack of epidemiological data points to the need to develop specific methods for detecting V. parahaemolyticus. In this note, the authors compare two plating media currently available for isolating V. parahaemolyticus in shellfish. Both approaches involve pre-enrichment of V. parahaemolyticus. One uses thiosulphate-citrate-bile salt sucrose (TCBS) as the isolation medium, while the other uses a chromogenic medium (CHROMagar Vibrio). Next, biochemical identification of isolates was performed with API 20E, followed by PCR assay aimed at the toxR gene to confirm the cultural and biochemical identification. Comparison of the two methods highlighted that CHROMagar Vibrio is more accurate and specific than TCBS. The analysis of data from 160 shellfish samples showed an accuracy and specificity of just 51% and 71% for TCBS compared with 88% and 95% for CAV. 相似文献
149.
Montagna MT Coretti C Lovero G De Giglio O Montagna O Laforgia N Santoro N Caggiano G 《International journal of molecular sciences》2011,12(9):5871-5877
Fungal sepsis is one of the major problems in neonatal and pediatric care unit settings. The availability of new diagnostic techniques could allow medical practitioners to rapidly identify septic patients and to improve their outcome. The aim of this study was to evaluate the performance of the 1→3-β-d-glucan (BDG), individually and in comparison with the Candida mannan (CM) antigen, in ten preterm infants and five onco-haematological pediatric patients with Candida bloodstream infections already proven by positive culture. The serum levels of BDG were >80 pg/mL on the same day as a positive blood culture in all examined patients, while CM antigen was negative in the patients with C. parapsilosis fungemia and in one further case due to C. albicans. These results suggest that a regular monitoring of serum circulating antigens (i.e., 1→3-β-d-glucan) combined with other microbiological and clinical information, may allow earlier and accurate diagnosis. However, further studies are necessary to confirm its usefulness in routine clinical practice. 相似文献
150.
Giacomo Cipriani Antonella Salvini Marco Fioravanti Giuseppina Di Giulio Marino Malavolti 《应用聚合物科学杂志》2013,127(1):420-431
Some oligo‐ or polyamides containing several hydroxyl groups were synthesized in order to obtain new water‐soluble compounds with a high affinity for polar materials as wood, paper, and natural fibers. The interest for the synthetic procedures is the use of renewable sources as starting compounds. In fact natural compounds or their derivatives, as l ‐tartaric acid, d (+)‐glucaric acid and α,α‐trehaluronic acid, were used as dicarboxylic acids in the polycondensation reactions, in order to obtain several functionalized oligoamides. All the compounds obtained in this study were characterized through FTIR and NMR spectroscopy. The oligoamides, water‐soluble and not provided with high‐molecular weights, were tested as wood consolidants. Physical properties like hygroscopicity of stabilized wood, volume shrinkage, density, and basic density were evaluated on the treated samples and compared with those obtained in the same conditions for an untreated archeological sample and a recent wood sample. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献