109 research outputs found
Hybrid Predictive Models for Accurate Forecasting in PV Systems
The accurate forecasting of energy production from renewable sources represents an important topic also looking at different national authorities that are starting to stimulate a greater responsibility towards plants using non-programmable renewables. In this paper the authors use advanced hybrid evolutionary techniques of computational intelligence applied to photovoltaic systems forecasting, analyzing the predictions obtained by comparing different definitions of the forecasting error
Analysis and validation of 24 hours ahead neural network forecasting of photovoltaic output power
In this paper an artificial neural network for photovoltaic plant energy forecasting is proposed and analyzed in terms of its
sensitivity with respect to the input data sets.
Furthermore, the accuracy of the method has been studied as a function of the training data sets and error definitions. The
analysis is based on experimental activities carried out on a real photovoltaic power plant accompanied by clear sky model.
In particular, this paper deals with the hourly energy prediction for all the daylight hours of the following day, based on 48 hours
ahead weather forecast. This is very important due to the predictive features requested by smart grid application: renewable energy
sources planning, in particular storage system sizing, and market of energy
Doxorubicin and congo red effectiveness on prion infectivity in golden Syrian hamster
The effect of doxorubicin and Congo Red on prion protein (PrP) infectivity in experimental scrapie was studied to better understand the effect of these compounds in prion diseases and to establish whether a dose-response correlation exists for Congo Red. This was performed in order to test the effectiveness of compounds that may easily be used in human prion diseases. Brain homogenate containing membrane bound PrPSc monomers was used as inoculum and was previously incubated with doxorubicin 10(-3) M and with increasing concentrations of Congo Red ranging from 10(-7) to 10(-2) M. This study shows for the first time that doxorubicin, and confirms that Congo Red, may interact with pathological PrP monomers modifying their infectious properties. Pre-incubation of infected brain homogenate with Congo Red resulted in prolonged incubation time and survival, independently of Congo Red concentration (p<0.05). Doxorubicin and Congo Red effects do not depend upon interaction with PrP amyloid material
A comparison of data mining approaches in the categorization of oral anticoagulation patients
Oral anticoagulation therapy, largely performed bywarfarin-based drugs, is commonly used for patientswith a high risk of blood clotting which can lead to
stroke or thrombosis. The state of the patient, with respect to anticoagulation, is captured by the index INR, which is to be kept within a therapeutic range.
The patients\u2019 response is marked by high interindividual and inter-temporal variability, which can
lead to serious adverse events. Polymorphisms of two genes CYP2C9 and VKORC1, considered markers of
lower dosage requirements, still account for a relatively minor part of this variability. In this work,
authors show that classification methods can identify groups of patients homogeneous with respect to the dynamics of INR. In particular, authors use classification methods in order to characterize patients
according to their warfarin metabolism and hence their sensitivity to different doses. Finally a Markov model to capture the dynamics of the patient\u2019sresponse over the years is propose
Laparoscopic paraesophageal hernia repair with absorbable mesh: a systematic review
Background: Laparoscopic repair is the standard of care for patients with paraesophageal hernia (PEH). Different prosthetic materials have been proposed to bolster the hiatus thus theoretically minimizing the probability for hernia recurrence. The use of non-absorbable mesh has been reported however, their safety profile has been questioned because the noteworthy mesh-related complication rate. Opposite, absorbable mesh (synthetic and biologic) seems associated with mitigated mesh-related complications and comparable hernia recurrence in the short- and medium-term. Methods: PubMed, MEDLINE, EMBASE, Scopus, Google Scholar, and ClinicalTrials.gov were executed according to the PRISMA statement until May 2022. Primary endpoints were technical details and surgical outcomes of adult patients (>= 18 years old) that underwent laparoscopic PEH repair and crural reinforcement with absorbable mesh. The ROBINS-I tool was used to assess the methodological quality of included studies. Results: Thirty-nine studies (3,103 patients) were included. The age of the patient population ranged from 18 to 93 years old and 62.8% were females. Posterior cruroplasty was performed in all patients. U-shape (83.7%), circumferential (8.1%), keyhole (5.4%) and starburst (2.8%) mesh configuration were described. Different methods for mesh fixation (sutures vs. fibrin glue vs. absorbable tacks) were adopted while Nissen (75.1%) and Toupet (21.1%) fundoplication were mainly fashioned. The overall postoperative complication rate was 2.5%. Pulmonary and cardiac complication rates were 1.8% and 0.9%, respectively while in-hospital mortality was 0.2%. Postoperative follow-up ranged from 12 to 166 months. Mesh-related complication rate was 0.06% (esophageal stricture related to fibrosis). Hernia recurrence rate was 12.7% while re-do surgery was required in 1.9% of patients. Postoperative dysphagia rate was 5.1%. Discussion: Consensus concerning the optimal mesh material for crural buttressing is lacking. Given the potential for tissue ingrowth rather than encapsulation and reduced degree of perivisceral inflammation, absorbable meshes are mostly preferred over non-absorbable meshes. The use of absorbable mesh seems safe and effective with low overall and mesh-related complications, acceptable recurrence rate and low need for re-do surgery in the short/medium-term. Because heterogeneity related to different hernia characteristics, intraoperative technical variations (i.e., method for mesh fixation, etc.), definition of hernia recurrence and diverse follow-up, a conclusive evidence is still to be defined
Remodelling of biological parameters during human ageing: evidence for complex regulation in longevity and in type 2 diabetes.
Factor structure analyses have revealed the presence of specific biological
system markers in healthy humans and diseases. However, this type of approach in
very old persons and in type 2 diabetes (T2DM) is lacking. A total sample of
2,137 Italians consisted of two groups: 1,604 healthy and 533 with T2DM. Age
(years) was categorized as adults (≤65), old (66-85), oldest old (>85-98) and
centenarians (≥99). Specific biomarkers of routine haematological and biochemical
testing were tested across each age group. Exploratory factorial analysis (EFA)
by principal component method with Varimax rotation was used to identify factors
including related variables. Structural equation modelling (SEM) was applied to
confirm factor solutions for each age group. EFA and SEM identified specific
factor structures according to age in both groups. An age-associated reduction of
factor structure was observed from adults to oldest old in the healthy group
(explained variance 60.4% vs 50.3%) and from adults to old in the T2DM group
(explained variance 57.4% vs 44.2%). Centenarians showed three-factor structure
similar to those of adults (explained variance 58.4%). The inflammatory component
became the major factor in old group and was the first one in T2DM. SEM analysis
in healthy subjects suggested that the glucose levels had an important role in
the oldest old. Factorial structure change during healthy ageing was associated
with a decrease in complexity but showed an increase in variability and
inflammation. Structural relationship changes observed in healthy subjects
appeared earlier in diabetic patients and later in centenarians
Ethnic disparity in access to the memory assessment service between South Asian and white British older adults in the United Kingdom: A cohort study
Background: Equality of access to memory assessment services by older adults from ethnic minorities is both an ethical imperative and a public health priority.Objective: To investigate whether timeliness of access to memory assessment service differs between older people of White British and South Asian ethnicity.Design: Longitudinal cohort.Setting: Nottingham Memory Study; outpatient secondary mental healthcare.Subjects: Our cohort comprised 3,654 White British and 32 South Asian older outpatients.Methods: The criterion for timely access to memory assessment service was set at 90 days from referral. Relationships between ethnicity and likelihood of timely access to memory assessment service were analysed using binary logistic regression. Analyses were adjusted for socio-demographic factors, deprivation and previous access to rapid response mental health services.Results: Among White British outpatients, 2,272 people (62.2%) achieved timely access to memory assessment service. Among South Asian outpatients, fourteen people (43.8%) achieved timely access to memory assessment service. After full adjustment, South Asian outpatients had a 0.47-fold reduced likelihood of timely access, compared to White British outpatients (odds ratio 0.47, 95% confidence interval 0.23-0.95, p-value=0.035). The difference became non-significant when restricting analyses to outpatients reporting British nationality or English as first language. Older age, lower index of deprivation and previous access to rapid response mental health services were associated with reduced likelihood of timely access, while gender was not.Conclusions: In a UK mental healthcare service, older South Asian outpatients are less likely to access dementia diagnostic services in a timely way, compared to White British outpatients
Immune parameters identify Italian centenarians with a longer five-year survival independent of their health and functional status.
Centenarians are rare and exceptional individuals characterized by a peculiar phenotype. They are the best ex- ample of healthy aging in humans as most of them have escaped or substantially delayed the onset of major age-related diseases. Within this scenario, the purpose of the present work was to understand if immune status is associated with survival and health status in centenarians. To this aim, 116 centenarians were concomitantly characterized for their immunological, health and functional status, and followed-up for five-year survival. On the basis of previous knowledge we focused on a core of fundamental and basic immune parameters (number of leukocytes, monocytes, total lymphocytes, CD3+ T lymphocytes, CD4+ helper T lymphocytes, CD8+ cytotoxic T lymphocytes, CD19+ B lymphocytes and plasma levels of IgM), and the most important findings can be sum- marized as follows: i. a hierarchical cluster analysis was able to define Cluster1 (88 centenarians) and Cluster2 (28 centenarians) characterized by low and high values of all these immune parameters, respectively; ii. cente- narians of Cluster2 showed a statistically longer five-year survival and more favorable values of other important immune (naïve, activated/memory and effector/memory T cells) and metabolic (glycemia, insulin and HOMA-IR) parameters, in accord with previous observations that centenarians have a peculiar immune profile, a preserved insulin pathway and a lower incidence of type 2 diabetes; and iii. unexpectedly, parameters related to frailty, as well as functional and cognitive status, did not show any significant correlation with the immune clustering, de- spite being capable per se of predicting survival. In conclusion, high values of basic immunological parameters and important T cell subsets correlate with five-year survival in centenarians, independent of other phenotypic characteristics. This unexpected biological scenario is compatible with the general hypothesis that in centenarians a progressive disconnection and loss of biological coherence among the different functions of the body occur, where survival/mortality result from the failure of any of these domains which apparently follow an independent age-related trajectory
双方向グラフの最大重み最小帰還辺集合問題について
Centenarians' offspring represent a suitable model to study age-dependent variables (e.g. IGF-I) potentially involved in the modulation of the lifespan. The aim of the present study was to investigate the role of the IGF-I in human longevity. We evaluated circulating IGF-I bioactivity measured by an innovative IGF-I Kinase Receptor Activation (KIRA) Assay, total IGF-I, IGFBP-3, total IGF-II, insulin, glucose, HOMA2-B% and HOMA2-S% in 192 centenarians' offspring and 80 offspring-controls of which both parents died relatively young. Both groups were well-matched for age, gender and BMI with the centenarians' offspring. IGF-I bioactivity (p\u30080.01), total IGF-I (p\u30080.01) and the IGF-I/IGFBP-3 molar ratio (p\u30080.001) were significantly lower in centenarians' offspring compared to offspring matched-controls. Serum insulin, glucose, HOMA2-B% and HOMA2-S% values were similar between both groups. In centenarians' offspring IGF-I bioactivity was inversely associated to insulin sensitivity. In conclusion: 1) centenarians' offspring had relatively lower circulating IGF-I bioactivity compared to offspring matched-controls; 2) IGF-I bioactivity in centenarians' offspring was inversely related to insulin sensitivity. These data support a role of the IGF-I/insulin system in the modulation of human aging process
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