250 research outputs found
Simplified Seismic Vulnerability Assessment Methods: A Comparative Analysis with Reference to Regional School Building Stock in Italy
The paper compares several simplified methods proposed in the literature for assessing the seismic vulnerability of existing buildings. Type and number of input and output data, limitations of use for different structural typologies, and complexity of use are examined for each methodology to identify the most suitable for assessing the vulnerability of a given class of buildings, based on the available data, the computational effort, and the type of vulnerability judgment. The selected methods were applied to a sample of school buildings located in the province of Naples (Italy). Data were available due to a digital platform and were used to verify the possibility of providing reliable large scale vulnerability judgments based on a reduced set of information, without carrying out additional surveys. The most simplified methods were applied to a sample of about a thousand of buildings, while more detailed methods, needing more information, were applied to a smaller sample. The comparison between the results obtained from different methods allows highlighting advantages and weaknesses of each, so as to identify the convenience in their use according to the specific available information and the objectives of the analysis, finally to evaluate which is more or less safe
Variable dampers to mitigate structural demand to wind turbines: The role of the monitoring system features for the effectiveness of the control strategy
In the last decade, some researchers and professionals have been engaged in the study of methods and techniques that can build high wind turbines while containing construction costs within the limits of economic convenience. Among the most promising solutions is that of using innovative devices to mitigate the structural demand for the towers. The reduction in the stress demand in the foundation makes the strategy particularly interesting for the repowering of existing plants, where it is convenient not to demolish and rebuild the foundation, but rather to reuse the existing one for the new plant. A semi-active vibration control strategy, based on the adoption of controllable dissipative devices, is presented herein. The proposed technique requires the tower to be equipped with a measurement system suitable for the real time monitoring of structural response. Performing reliable high-frequency measurements of the horizontal displacement of points located at heights of tens of meters is not simple. With the purpose of assessing the efficiency and feasibility of Global Navigation Satellite System (GNSS)-based systems for the control of wind turbine structures, the proposed paper tries to investigate the characteristics and data processing techniques that are able to make the GNSS useful for such applications. Several numerical simulations were carried out with reference to a case-study wind turbine to quantitatively assess how the performance of the control system changes as the features of the monitoring system worsen, and finally to draw conclusions and suggestions for the minimum performance that monitoring devices must have for an effective reduction in structural demand
Computer-aided decision making for regional seismic risk mitigation accounting for limited economic resources
Seismic risk mitigation levels for an existing building are a balance between the reduction of risk and the cost of rehabilitation. Evidently, the more that is paid the more risk is reduced; however, due to limited public budgets a practical approach is needed to manage the risk reduction program when a portfolio of buildings is concerned. Basically, decision makers face a challenge when there are a large number of vulnerable buildings and there is no plan for how to allocate the appointed budget. This study develops a technological platform that implements a decision-making procedure to establish how to optimally distribute the budget in order to achieve the maximum possible portfolio risk reduction. Decisions are made based on various presumed intervention strategies dependent on building’s level of risk. The technological platform provides an interactive, user-friendly tool, available online, that supports stakeholders and decision makers in understanding what the best economic resource allocation will be after selecting the available budget for a specific portfolio of buildings. In addition, the ease of use enables the user to analyze the extent of risk reduction achievable for different budget levels. Therefore, the web platform represents a powerful tool to accomplish two challenging tasks, namely optimal budget selection and optimal budget allocation to gain territorial seismic risk mitigation
Casi e materiali di diritto commerciale
Il volume raccoglie i casi trattati nelle esercitazioni di Diritto
Commerciale I e II nel corso dell’A.A. 2012/2013. Esso vuole costituire,
prima di tutto, per gli studenti che frequentano i corsi di Diritto
commerciale uno strumento di approfondimento e conoscenza nel concreto
dell’applicazione giurisprudenziale delle principali tematiche affrontate
a lezione e una guida per la partecipazione alle esercitazioni;
ma ancor più serve agli studenti che, per scelta o per necessità, non
frequentano i corsi, in quanto li mette di fronte ad una diversa prospettiva
di analisi delle norme e li aiuta a comprendere ragioni
e metodi dello studio del Diritto Commerciale, più di quanto potrebbe
fare la semplice lettura non guidata dei testi didattici e delle norme. Ciascun caso viene presentato secondo uno schema standard:
1) il provvedimento e gli eventuali atti, sfrondati delle parti non
strettamente necessarie agli scopi didattici;
2) i titoletti (che servono a classificare la pronuncia secondo partizioni
prefissate, consentendo al lettore di individuare immediatamente
l’argomento cui attiene e il principio di diritto affermato);
3) i richiami normativi, che individuano le norme la cui lettura e
comprensione è indispensabile allo studio del caso;
4) la massima, che enuncia analiticamente il principio di diritto
contenuto nel provvedimento;
5) il commento, che guida il lettore attraverso il ragionamento
condotto dal giudice, indicandogli il percorso logico/giuridico e le regole
di diritto positivo utilizzate per la soluzione del caso;
6) le indicazioni bibliografiche, volutamente non troppo ampie,
giacché si limitano a rimandare ad alcune fonti ulteriori che rappresentano
punti di partenza basilari per avviare uno studio analitico di ciascuna
tematica.
Talvolta al centro dell’approfondimento non è una pronuncia giurisprudenziale,
ma un documento, parimenti idoneo ad illuminare
aspetti problematici o particolarmente interessanti nella prospettiva
dello studio del Diritto commerciale. In questo caso, al documento seguono
immediatamente il commento/guida alla lettura e le indicazioni
bibliografiche. I temi ruotano intorno ai nuclei fondamentali del diritto commerciale.
L’impresa, innanzitutto, nelle sue articolate qualificazioni di impresa
commerciale, agricola e artigiana, nonché negli aspetti concorrenziali.
Il diritto societario, nella “summa divisio” fra società personali
e società di capitali, senza trascurare i problemi che l’approvvigionamento
dei mezzi finanziari sul mercato solleva a carico dei risparmiatori.
E le procedure concorsuali, declinate soprattutto nel fallimento,
che – nonostante la travagliata e sempre incompiuta riforma –
resta al centro del sistema concorsuale
CCR5-∆32, CCR2-64I, SDF1-3'A, and IFNλ4 rs12979860 and rs8099917 gene polymorphisms in individuals with HIV-1, HIV/HTLV-1, and HIV/HTLV-2 in São Paulo, Brazil
Background. Chemokine and chemokine-receptor polymorphisms have been associated with protection against HIV infection and delayed progression to AIDS, whereas polymorphisms in IFNλ4 (formerly IL28B) have been associated with human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy (HAM) development. Evolutionary selection against ancestral genes differs among human populations, resulting in varying risks of acquiring and developing viral diseases. Methods. DNA samples from 434 patients infected with HIV-1 and/or co-infected with HTLV-1/-2, and samples from 74 HIV and HTLV non-infected individuals from São Paulo, Brazil, were divided into five groups: HIV-naïve, n=160; HIV-ART, n=180; HIV/HTLV-1, n=53; HIV/HTLV-2, n=41; and control, n=74. These samples were analyzed for CCR5-∆32 deletion, CCR2-64I, SDF1-3'A, and IFNλ4 rs12979860 and rs8099917 single nucleotide polymorphisms using PCR and PCR-RFLP techniques. These polymorphisms' genotype and allele frequencies were calculated and compared among groups using logistic regression analysis. Results. All polymorphism profiles described in the literature were detected in this study. The wild-type genotype predominated in all genes analyzed except for IFNλ4 rs12979860. Statistical differences in allele frequencies among groups were detected in the CCR5 and CCR2 genes, with a high frequency of ∆32 in HIV-naïve vs. HIV-ART (OR 2.45, P=0.037) and a minus mutant allele A (CCR2-64I) in HIV-naïve vs. HIV/HTLV-1 (OR 1.90, P=0.048), HIV-ART vs. HIV/HTLV-1 (OR 2.62, P=0.003), and HIV/ART vs. HIV/HTLV-2 (OR 2.42, P=0.016). Conclusions. The polymorphism profiles detected in the study groups corroborate the profiles described in racial admixed populations. High CCR2-64I mutant allele frequencies were detected in HIV/HTLV-1/-2 co-infected individuals, and CCR5-∆32 showed predictive value for ART initiation
Definitions of Urinary Tract Infection in Current Research: A Systematic Review
Defining urinary tract infection (UTI) is complex, as numerous clinical and diagnostic parameters are involved. In this systematic review, we aimed to gain insight into how UTI is defined across current studies. We included 47 studies, published between January 2019 and May 2022, investigating therapeutic or prophylactic interventions in adult patients with UTI. Signs and symptoms, pyuria, and a positive urine culture were required in 85%, 28%, and 55% of study definitions, respectively. Five studies (11%) required all 3 categories for the diagnosis of UTI. Thresholds for significant bacteriuria varied from 103 to 105 colony-forming units/mL. None of the 12 studies including acute cystitis and 2 of 12 (17%) defining acute pyelonephritis used identical definitions. Complicated UTI was defined by both host factors and systemic involvement in 9 of 14 (64%) studies. In conclusion, UTI definitions are heterogeneous across recent studies, highlighting the need for a consensus-based, research reference standard for UTI
Economic analysis of antenatal screening for human T-cell lymphotropic virus type 1 in Brazil: an open access cost-utility model
BACKGROUND: Human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that causes severe diseases, such as aggressive cancer or progressive neurological disease. HTLV-1 affects mainly people in areas with low human development index and can be transmitted from mother to child, primarily through breastfeeding. Refraining from breastfeeding is an effective intervention to reduce the risk of infection in infants. However, HTLV-1 antenatal screening is not offered globally. According to WHO, the scarcity of cost-effectiveness studies is considered one of the major barriers to the implementation of policies to prevent HTLV-1 infection. Therefore, this study aimed to assess the cost-effectiveness of antenatal screening and postnatal interventions to prevent HTLV-1 mother-to-child transmission in Brazil and to develop an open-access, editable, mathematical model that can be used by other countries and regions to assess different scenarios. METHODS: In this cost-utility analysis, we constructed a decision tree and a Markov model to assess the cost-effectiveness of HTLV-1 antenatal screening and postnatal interventions (ie, avoidance of breastfeeding, by suppression of lactation with cabergoline, and provision of formula feed) to reduce transmission. For our model, we used data from Brazil and we took the perspective of the public health-care system to estimate costs. FINDINGS: The implementation of both screening and interventions would result in the prevention of 1039 infections in infants every year in Brazil with an incremental cost-effectiveness ratio (ICER) of US18 107·74 per QALY). HTLV-1 prevalence in pregnant women, the risk of HTLV-1 transmission when breastfeeding lasts for 6 months or more, and the cost of screening tests were the variables with the largest effect on ICER. INTERPRETATION: HTLV-1 antenatal screening is cost-effective in Brazil. An open-access model was developed, and this tool could be used to assess the cost-effectiveness of such policy globally, favouring the implementation of interventions to prevent HTLV-1 mother-to-child transmission worldwide. FUNDING: None. TRANSLATIONS: For the Portuguese and Spanish translations of the abstract see Supplementary Materials section
Structural Analysis of Biodiversity
Large, recently-available genomic databases cover a wide range of life forms, suggesting opportunity for insights into genetic structure of biodiversity. In this study we refine our recently-described technique using indicator vectors to analyze and visualize nucleotide sequences. The indicator vector approach generates correlation matrices, dubbed Klee diagrams, which represent a novel way of assembling and viewing large genomic datasets. To explore its potential utility, here we apply the improved algorithm to a collection of almost 17000 DNA barcode sequences covering 12 widely-separated animal taxa, demonstrating that indicator vectors for classification gave correct assignment in all 11000 test cases. Indicator vector analysis revealed discontinuities corresponding to species- and higher-level taxonomic divisions, suggesting an efficient approach to classification of organisms from poorly-studied groups. As compared to standard distance metrics, indicator vectors preserve diagnostic character probabilities, enable automated classification of test sequences, and generate high-information density single-page displays. These results support application of indicator vectors for comparative analysis of large nucleotide data sets and raise prospect of gaining insight into broad-scale patterns in the genetic structure of biodiversity
Assessing the Value of DNA Barcodes and Other Priority Gene Regions for Molecular Phylogenetics of Lepidoptera
BACKGROUND: Despite apparently abundant amounts of observable variation and species diversity, the order Lepidoptera exhibits a morphological homogeneity that has provided only a limited number of taxonomic characters and led to widespread use of nucleotides for inferring relationships. This study aims to characterize and develop methods to quantify the value of priority gene regions designated for Lepidoptera molecular systematics. In particular, I assess how the DNA barcode segment of the mitochondrial COI gene performs across a broad temporal range given its number one position of priority, most sequenced status, and the conflicting opinions on its phylogenetic performance. METHODOLOGY/PRINCIPAL FINDINGS: Gene regions commonly sequenced for lepidoptera phylogenetics were scored using multiple measures across three categories: practicality, which includes universality of primers and sequence quality; phylogenetic utility; and phylogenetic signal. I found that alternative measures within a category often appeared correlated, but high scores in one category did not necessarily translate into high scores in another. The DNA barcode was easier to sequence than other genes, and had high scores for utility but low signal above the genus level. CONCLUSIONS/SIGNIFICANCE: Given limited financial resources and time constraints, careful selection of gene regions for molecular phylogenetics is crucial to avoid wasted effort producing partially informative data. This study introduces an approach to assessing the value of gene regions prior to the initiation of new studies and presents empirical results to help guide future selections
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