Application of pso-ann modelling for predicting the exergetic performance of a building integrated photovoltaic/thermal system

The main objective of this study is to examine the feasibility of hybrid PSO–ANN technique to estimate the exergetic performance of a building integrated photovoltaic/thermal (BIPV/T) system. A performance evaluation criterion (PEC) is defined in this study to assess the overall performance of a BIPV/T system from exergy point of view. Then, the mentioned method is utilized to identify a relationship between the input and output parameters of the BIPV/T system. The parameter PEC was taken as the essential output of the BIPV/T system, while the input parameters were channel length, channel depth, channel width, and air mass flow rate. Prior to PSO, variables of ANN algorithm were optimized. In addition, PSO influential parameters such as swarm size, personal learning coefficient, global learning coefficient, and inertia weight were optimized using a series of trial-and-error process. The predicted results for data sets from ANN and PSO–ANN models were evaluated according to several known statistical indices and novel ranking systems of color intensity rating and total ranking method. The obtained RMSE and R2 in the training (RMSE of 0.010274 and 0.006112, and R2 of 0.9968 and 0.9989, respectively, for the PSO and ANN methods) and testing (RMSE of 0.011146 and 0.005927, and R2 of 0.9967 and 0.9990, respectively, for the PSO and ANN methods) phases. The results revealed that the PSO–ANN network model could slightly accomplish a better performance when it is compared to the conventional ANN

Low-temperature amino-based catalyst activation for on-demand polyurethane synthesis

A new latent catalyst, based on 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), has been specifically designed to be thermally deprotected at low temperature. More generally, specific isocyanurates based on the reaction of two substituted isocyanates and DBN are used as pre-catalyst for polyurethane synthesis. The activation temperature of the pre-catalysts is determined by DSC and resulting free catalysts activity is demonstrated through a catalysis cycle on a PU model reaction

A Novel Fic (Filamentation Induced by cAMP) Protein from Clostridium difficile Reveals an Inhibitory Motif-independent Adenylylation/AMPylation Mechanism

Filamentation induced by cAMP (Fic) domain proteins have been shown to catalyze the transfer of the AMP moiety from ATP onto a protein target. This type of post-translational modification was recently shown to play a crucial role in pathogenicity mediated by two bacterial virulence factors. Herein we characterize a novel Fic domain protein that we identified from the human pathogen Clostridium difficile. The crystal structure shows that the protein adopts a classical all-helical Fic fold, which belongs to class II of Fic domain proteins characterized by an intrinsic N-terminal autoinhibitory alpha-helix. A conserved glutamate residue in the inhibitory helix motif was previously shown in other Fic domain proteins to prevent proper binding of the ATP gamma-phosphate. However, here we demonstrate that both ATP binding and autoadenylylation activity of the C. difficile Fic domain protein are independent of the inhibitory motif. In support of this, the crystal structure of a mutant of this Fic protein in complex with ATP reveals that the gamma-phosphate adopts a conformation unique among Fic domains that seems to override the effect of the inhibitory helix. These results provide important structural insight into the adenylylation reaction mechanism catalyzed by Fic domains. Our findings reveal the presence of a class II Fic domain protein in the human pathogen C. difficile that is not regulated by autoinhibition and challenge the current dogma that all class I-III Fic domain proteins are inhibited by the inhibitory alpha-helix.Proteomic

Chemotherapy in locally advanced nasopharyngeal carcinoma: An individual patient data meta-analysis of eight randomized trials and 1753 patients

Objectives: To study the effect of adding chemotherapy to radiotherapy (RT) on overall survival and event-free survival for patients with nasopharyngeal carcinoma. Methods and Materials: This meta-analysis used updated individual patient data from randomized trials comparing chemotherapy plus RT with RT alone in locally advanced nasopharyngeal carcinoma. The log-rank test, stratified by trial, was used for comparisons, and the hazard ratios of death and failure were calculated. Results: Eight trials with 1753 patients were included. One trial with a 2 × 2 design was counted twice in the analysis. The analysis included 11 comparisons using the data from 1975 patients. The median follow-up was 6 years. The pooled hazard ratio of death was 0.82 (95% confidence interval, 0.71-0.94; p = 0.006), corresponding to an absolute survival benefit of 6% at 5 years from the addition of chemotherapy (from 56% to 62%). The pooled hazard ratio of tumor failure or death was 0.76 (95% confidence interval, 0.67-0.86; p < 0.0001), corresponding to an absolute event-free survival benefit of 10% at 5 years from the addition of chemotherapy (from 42% to 52%). A significant interaction was observed between the timing of chemotherapy and overall survival (p = 0.005), explaining the heterogeneity observed in the treatment effect (p = 0.03), with the highest benefit resulting from concomitant chemotherapy. Conclusion: Chemotherapy led to a small, but significant, benefit for overall survival and event-free survival. This benefit was essentially observed when chemotherapy was administered concomitantly with RT. © 2006 Elsevier Inc.link_to_subscribed_fulltex

Chemotherapy as an adjunct to radiotherapy in locally advanced nasopharyngeal carcinoma.

BACKGROUND: A previous meta-analysis investigated the role of chemotherapy in head and neck locally advanced carcinoma. This work had not been performed on nasopharyngeal carcinoma. OBJECTIVES: The aim of the project was to study the effect of adding chemotherapy to radiotherapy on overall survival (OS) and event-free survival (EFS) in patients with nasopharyngeal carcinoma. SEARCH STRATEGY: We searched MEDLINE (1966 to October 2003), EMBASE (1980 to October 2003) and the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 3, 2003) and trial registers. Handsearches of meeting abstracts, references in review articles and of the Chinese medical literature were carried out. Experts and pharmaceutical companies were asked to identify trials. SELECTION CRITERIA: Randomised trials comparing chemotherapy plus radiotherapy to radiotherapy alone in locally advanced nasopharyngeal carcinoma were included. DATA COLLECTION AND ANALYSIS: The meta-analysis was based on updated individual patient data. The log rank test, stratified by trial, was used for comparisons and the hazard ratios (HR) of death and failure (loco-regional/distant failure or death) were calculated. MAIN RESULTS: Eight trials with 1753 patients were included. One trial with a 2 x 2 design was counted twice in the analysis. The analysis was performed including 11 comparisons based on 1975 patients. The median follow up was six years. The pooled hazard ratio of death was 0.82 (95% confidence interval (CI) 0.71 to 0.95; P = 0.006) corresponding to an absolute survival benefit of 6% at five years from chemotherapy (from 56% to 62%). The pooled hazard ratio of tumour failure or death was 0.76 (95% CI 0.67 to 0.86; P < 0.00001) corresponding to an absolute event-free survival benefit of 10% at five years from chemotherapy (from 42% to 52%). A significant interaction was observed between chemotherapy timings and overall survival (P = 0.005), explaining the heterogeneity observed in the treatment effect (P = 0.03) with the highest benefit from concomitant chemotherapy. AUTHORS' CONCLUSIONS: Chemotherapy led to a small but significant benefit for overall survival and event-free survival. This benefit was essentially observed when chemotherapy was administered concomitantly with radiotherapy.link_to_subscribed_fulltex

Diversity and geographic distribution of haplotypes of Dirofilaria immitis across European endemic countries

Background Dirofilaria immitis, also known as heartworm, is one of the most important parasitic nematodes of domestic dogs, causing a potentially serious disease, cardiopulmonary dirofilariosis, which can be lethal. This species seems to be less 'expansive' than its sister species Dirofilaria repens, and it is believed that climate change facilitates the spread of this parasite to new non-endemic regions.Methods In total, 122 heartworm isolates were analysed from nine endemic countries in Europe (Portugal, Spain, Italy, Greece, Hungary, Romania, Slovakia, and Ukraine) and a single isolate from Bangladesh by amplification and sequencing of two mitochondrial (mt) DNA markers: cytochrome c oxidase subunit 1 (COI) and dehydrogenase subunit 1 (NADH). The main aim of the current study was to determine the genetic diversity of D. immitis and compare it with D. repens haplotype diversity and distribution. DNA was extracted from adult heartworms or microfilariae in blood. Most isolates originated from dogs (Canis lupus familiaris) while 10 isolates originated from wildlife species from Romania, including eight isolates from golden jackals (Canis aureus), one isolate from a Eurasian otter (Lutra lutra) and one isolate from a red fox (Vulpes vulpes).Results Median spanning network analysis was based on the combined sequence (1721 bp) obtained from two mt markers and successfully delineated nine haplotypes (Di1-Di9). Haplotype Di1 was the dominant haplotype encompassing 91 out of the 122 sequences (75%) from all nine countries and four host species. Haplotype Di2 was the second most common haplotype, formed solely by 13 isolates from Italy. The remaining sequences were assigned to Di3-Di9 haplotypes, differing by 1-4 SNPs from the dominant Di1 haplotype. There was evidence for geographical segregation of haplotypes, with three unique haplotypes associated with Italy and four others associated with certain countries (Di4 and Di7 with Slovakia; Di8 with Greece; Di6 with Hungary).Conclusion Diversity in D. immitis mt haplotypes was lower by half than in D. repens (9 vs. 18 haplotypes in D. immitis and D. repens, respectively), which may be associated with the slower expansion of heartworm in Central and NE Europe. NADH gene appears to be conserved in Dirofilaria sp. by showing lower genetic diversity than the analysed COI gene