1,721,089 research outputs found
Obesità e osteoporosi
No full textil capitolo tratta dell'epidemiologia dell'osteoporosi e delle fratture dafragilità nell'obeso e delle correlazioni fisiopatologiche e endocrinometaboliche tra tessuto adiposo e tessuto osseo
Bisphosphonates and osteomyelitis of the jaw: a pathogenic puzzle
No full textThe maxillary and mandibular bones undergo high-turnover remodeling to maintain mechanical competence. Common dental or periodontal diseases can increase local bone turnover. Bisphosphonates (Bps) accumulate almost exclusively in skeletal sites that have active bone remodeling. The maxillary and mandibular bones are preferential sites for accumulation of Bps, which become buried under new layers of bone and remain biologically inactive for a long time. Surgical odontostomatological procedures create open bony wounds that heal quickly and without infection, as a result of activation of osteoclasts and subsequently osteoblasts. Once Bps are removed from the bone via activation of osteoclasts after a tooth extraction or a periodontal procedure, they induce osteoclast apoptosis. This inhibition of osteoclast bone resorption impairs bone wound healing because of decreased production of cytokines derived from the bone matrix, and the bone is exposed to the risk of osteomyelitis and necrosis. The pathogenic relationship between Bps and osteonecrosis of the jaw is unclear, but there is evidence to indicate an association between high-dose BP treatment and exposure to dental infections or oral surgical procedures. A better knowledge of the interactions between Bps and jaw and maxillary bone biology will improve clinical and therapeutic approaches
Experimental Testing of a Wind Power Plant with IEC 61400-27 Models for Voltage Regulation Service in Italy
No full textSystem operators specify different grid services which can be potentially provided by generation units based on renewable energy sources as wind power plants. Those services concern different aspects of system operation and they are defined with specific remuneration schemes. The generation plant aiming to get the remuneration for a given service must fulfill the requirements imposed for that service by the system operator. The paper presents modeling and tuning of an existing wind power plant in Italy for the participation of the wind plant in a voltage regulation service published by the Italian system operator Terna. The wind power plant is composed by 22 2-MW wind turbines and it is modeled for dynamic simulation as Type 3 according to the IEC 61400-27-1 Edition 2 Standard. The model is validated against field measurements obtained by the SCADA system of the wind plant for a reactive power reference step. In order to match the experimental data and overcome the problem of some unknown control parameters, a parameter identification and tuning for the plant controllers is first performed. The validated model is then used to provide a proper parameters adjustment for the compliance of the wind power plant to the voltage regulation service indicated by the system operator
The Italian Version of the Career Factors Inventory
Full text linkThis study attempted to examine the validity of the Italian version of the Career Factors Inventory (CFI), a psychometric tool widely used in the assessment of cognitive and personalâemotional dimensions of career indecision, among a sample of 2,060 Italian students attending high school and university. Recurring to both exploratory and confirmatory factor analyses, the original four-factor structure was confirmed and returned, in line with the literature, satisfactory reliability indices; moreover, CFI subscales showed intercorrelations consistent with previous studies, albeit lower in some cases. Subsequently, convergent validity between the four CFI subscales and other scales via zero-order correlation was tested, confirming previous evidence except for need for career information. In conclusion, consistent with previous studies, the Italian version of the CFI showed to be a valid and reliable instrument for the evaluation of dimensions of career indecision
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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