260 research outputs found
Zero-inertia Offshore Grids: N-1 Security and Active Power Sharing
With Denmark dedicated to maintaining its leading position in the integration
of massive shares of wind energy, the construction of new offshore energy
islands has been recently approved by the Danish government. These new islands
will be zero-inertia systems, meaning that no synchronous generation will be
installed in the island and that power imbalances will be shared only among
converters. To this end, this paper proposes a methodology to calculate and
update the frequency droops gains of the offshore converters in compliance with
the N-1 security criterion in case of converter outage. The frequency droop
gains are calculated solving an optimization problem which takes into
consideration the power limitations of the converters as well as the stability
of the system. As a consequence, the proposed controller ensures safe operation
of off-shore systems in the event of any power imbalance and allows for greater
loadability at pre-fault state, as confirmed by the simulation results.Comment: Submitted to "IEEE Transactions on Power Systems" on February 19,
202
REPETITA: detection and discrimination of the periodicity of protein solenoid repeats by discrete Fourier transform
Motivation: Proteins with solenoid repeats evolve more quickly than non-repetitive ones and their periodicity may be rapidly hidden at sequence level, while still evident in structure. In order to identify these repeats, we propose here a novel method based on a metric characterizing amino-acid properties (polarity, secondary structure, molecular volume, codon diversity, electric charge) using five previously derived numerical functions
Costs of chronic obstructive pulmonary disease (COPD) in Italy: The SIRIO study (Social Impact of Respiratory Integrated Outcomes)
SummaryChronic respiratory diseases affect a large number of subjects in Italy and are characterized by high socio-health costs. The aim of the Social Impact of Respiratory Integrated Outcomes (SIRIO) study was to measure the health resources consumption and costs generated in 1 year by a population of patients with chronic obstructive pulmonary disease (COPD) in a real-life setting. This bottom-up, observational, prospective, multicentric study was based on the collection of demographic, clinical, diagnostic, therapeutic and outcome data from COPD patients who reported spontaneously to pneumological centers participating in the study, the corresponding economic outcomes being assessed at baseline and after a 1-year survey. A total of 748 COPD patients were enrolled, of whom 561 [408m, mean age 70.3 years (SD 9.2)] were defined as eligible by the Steering Committee. At the baseline visit, the severity of COPD (graded according to GOLD 2001 guidelines) was 24.2% mild COPD, 53.7% moderate and 16.8% severe. In the 12 months prior to enrollment, 63.8% visited a general practitioner (GP); 76.8% also consulted a national health service (NHS) specialist; 22.3% utilized Emergency Care and 33% were admitted to hospital, with a total of 5703 work days lost. At the end of the 1-year survey, the severity of COPD changed as follows: 27.5% mild COPD, 47.4% moderate and 19.4% severe. Requirement of health services dropped significantly: 57.4% visited the GP; 58.3% consulted an NHS specialist; 12.5% used Emergency Care and 18.4% were hospitalized. Compared to baseline, the mean total cost per patient decreased by 21.7% (p<0.002). In conclusion, a significant reduction in the use of health resources and thus of COPD-related costs (both direct and indirect costs) was observed during the study, likely due to a more appropriate care and management of COPD patients
Critical assessment of protein intrinsic disorder prediction (CAID) - Results of round 2
Protein intrinsic disorder (ID) is a complex and context-dependent phenomenon that covers a continuum between fully disordered states and folded states with long dynamic regions. The lack of a ground truth that fits all ID flavors and the potential for order-to-disorder transitions depending on specific conditions makes ID prediction challenging. The CAID2 challenge aimed to evaluate the performance of different prediction methods across different benchmarks, leveraging the annotation provided by the DisProt database, which stores the coordinates of ID regions when there is experimental evidence in the literature. The CAID2 challenge demonstrated varying performance of different prediction methods across different benchmarks, highlighting the need for continued development of more versatile and efficient prediction software. Depending on the application, researchers may need to balance performance with execution time when selecting a predictor. Methods based on AlphaFold2 seem to be good ID predictors but they are better at detecting absence of order rather than ID regions as defined in DisProt. The CAID2 predictors can be freely used through the CAID Prediction Portal, and CAID has been integrated into OpenEBench, which will become the official platform for running future CAID challenges
The repetitive structure of DNA clamps: An overlooked protein tandem repeat
Structured tandem repeats proteins (STRPs) are a specific kind of tandem repeat proteins characterized by a modular and repetitive three-dimensional structure arrangement. The majority of STRPs adopt solenoid structures, but with the increasing availability of experimental structures and high-quality predicted structural models, more STRP folds can be characterized. Here, we describe “Box repeats”, an overlooked STRP fold present in the DNA sliding clamp processivity factors, which has eluded classification although structural data has been available since the late 1990s. Each Box repeat is a β⍺βββ module of about 60 residues, which forms a class V “beads-on-a-string” type STRP. The number of repeats present in processivity factors is organism dependent. Monomers of PCNA proteins in both Archaea and Eukarya have 4 repeats, while the monomers of bacterial beta-sliding clamps have 6 repeats. This new repeat fold has been added to the RepeatsDB database, which now provides structural annotation for 66 Box repeat proteins belonging to different organisms, including viruses
CAID prediction portal: A comprehensive service for predicting intrinsic disorder and binding regions in proteins
Intrinsic disorder (ID) in proteins is well-established in structural biology, with increasing evidence for its involvement in essential biological processes. As measuring dynamic ID behavior experimentally on a large scale remains difficult, scores of published ID predictors have tried to fill this gap. Unfortunately, their heterogeneity makes it difficult to compare performance, confounding biologists wanting to make an informed choice. To address this issue, the Critical Assessment of protein Intrinsic Disorder (CAID) benchmarks predictors for ID and binding regions as a community blind-test in a standardized computing environment. Here we present the CAID Prediction Portal, a web server executing all CAID methods on user-defined sequences. The server generates standardized output and facilitates comparison between methods, producing a consensus prediction highlighting high-confidence ID regions. The website contains extensive documentation explaining the meaning of different CAID statistics and providing a brief description of all methods. Predictor output is visualized in an interactive feature viewer and made available for download in a single table, with the option to recover previous sessions via a private dashboard. The CAID Prediction Portal is a valuable resource for researchers interested in studying ID in proteins. The server is available at the URL: https://caid.idpcentral.org
Endometrial Cancer Risk Prediction According to Indication of Diagnostic Hysteroscopy in Post-Menopausal Women
We conducted a prospective observational study investigating the clinical relevance of
endometrial thickness (ET) and abnormal uterine bleeding (AUB) on endometrial cancer (EC) risk in a cohort of postmenopausal patients undergoing diagnostic hysteroscopy and endometrial biopsy. Patients were divided into two groups according to the indication of diagnostic hysteroscopy: ET_Group (asymptomatic patients with endometrial thickness 4 mm) and AUB_Group (patients with a history of abnormal uterine bleeding). We further divided the AUB_Group into two subgroups based on endometrial thickness (AUB_Subgroup1: ET < 4 mm; AUB_Subgroup2: ET 4 mm).
The primary outcome was the risk of endometrial cancer and atypical hyperplasia according to the indications of diagnostic hysteroscopy (AUB, ET 4 mm or both). The secondary outcome was to determine the best cut-o value of endometrial thickness to predict endometrial cancer in asymptomatic postmenopausal women. The prevalence of endometrial cancer and atypical hyperplasia in AUB_Group and ET_Group was 21% and 6.7% respectively. As well as for EC alone, higher prevalence of both conditions was observed in AUB_Subgroup2 (29.3%) in comparison to AUB_Subgroup1 (10.6%; p < 0.001). In asymptomatic patients the cut-o of endometrial thickness
that showed the best sensitivity and specificity to diagnose endometrial cancer (100% and 80% respectively) was 11 mm (AUC of 91.4%; Exp : 1067; CI 95%). In conclusion, considering the high risk of neoplasia, diagnostic hysteroscopy with endometrial biopsy should be mandatory in cases of abnormal uterine bleeding in postmenopausal patients. Moreover, we want to emphasize the need for further evidence stating the clinical relevance of endometrial thickness value in asymptomatic patients and the impact of individual risk factors on endometrial cancer development
Oxygen Therapy in Advanced Disease: Do You Know the Evidence?
A dispneia é um dos sintomas que tem mais impacto tanto para o doente com doença avançada, como para o profissional de saúde com a responsabilidade de o acompanhar. Sem prejuízo de se dever aprofundar a evidência disponível sobre as indicações e eficácia da oxigenoterapia, é já vasta a informação que suporta a evidência de que o uso de oxigénio com intenção paliativa deve ser prescrito de forma criteriosa pois, à semelhança de qualquer outro tratamento, tem efeitos secundários associados e pode causar malefícios. O artigo que se apresenta é uma revisão bibliográfica das mais recentes matérias publicadas neste âmbito, com o objetivo de contribuir para melhorar a prática clínica no contexto do tratamento dos doentes em fim de vida.info:eu-repo/semantics/publishedVersio
Critical assessment of protein intrinsic disorder prediction
Intrinsically disordered proteins, defying the traditional protein structure–function paradigm, are a challenge to study experimentally. Because a large part of our knowledge rests on computational predictions, it is crucial that their accuracy is high. The Critical Assessment of protein Intrinsic Disorder prediction (CAID) experiment was established as a community-based blind test to determine the state of the art in prediction of intrinsically disordered regions and the subset of residues involved in binding. A total of 43 methods were evaluated on a dataset of 646 proteins from DisProt. The best methods use deep learning techniques and notably outperform physicochemical methods. The top disorder predictor has F max = 0.483 on the full dataset and F max = 0.792 following filtering out of bona fide structured regions. Disordered binding regions remain hard to predict, with F max = 0.231. Interestingly, computing times among methods can vary by up to four orders of magnitude
- …