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The peak stress method (PSM) allows a rapid application of the notch stress intensity factor (NSIF) approach to the fatigue life assessment of welded structures, by employing the linear elastic peak stresses evaluated by FE analyses with coarse meshes. Because of the widespread adoption of 3D modeling of large and complex structures in the industry, the PSM has recently been boosted by including four-node and ten-node tetrahedral elements of Ansys FE software, which allows to discretize complex geometries. In this paper, a Round Robin among eleven Italian Universities has been performed to calibrate the PSM with seven different commercial FE software packages. Several 3D mode I, II and III problems have been considered to investigate the influence of (i) FE code, (ii) element type, (iii) mesh pattern, and (iv) procedure to extrapolate stresses at FE nodes. The majority of the adopted FE software packages present similar values of the PSM parameters, the main source of discrepancy being the stress extrapolation method at FE nodes.

Antipsychotic drugs are the mainstay treatment for schizophrenia, yet they are associated with diverse and potentially dose-related side effects which can reduce quality of life. For this reason, the lowest possible doses of antipsychotics are generally recommended, but higher doses are often used in clinical practice. It is still unclear if and how antipsychotic doses could be reduced safely in order to minimise the adverse-effect burden without increasing the risk of relapse.To assess the efficacy and safety of reducing antipsychotic dose compared to continuing the current dose for people with schizophrenia.We conducted a systematic search on 10 February 2021 at the Cochrane Schizophrenia Group's Study-Based Register of Trials, which is based on CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, PubMed, ClinicalTrials.gov, ISRCTN, and WHO ICTRP. We also inspected the reference lists of included studies and previous reviews.We included randomised controlled trials (RCTs) comparing any dose reduction against continuation in people with schizophrenia or related disorders who were stabilised on their current antipsychotic treatment. DATA COLLECTION AND ANALYSIS: At least two review authors independently screened relevant records for inclusion, extracted data from eligible studies, and assessed the risk of bias using RoB 2. We contacted study authors for missing data and additional information. Our primary outcomes were clinically important change in quality of life, rehospitalisations and dropouts due to adverse effects; key secondary outcomes were clinically important change in functioning, relapse, dropouts for any reason, and at least one adverse effect. We also examined scales measuring symptoms, quality of life, and functioning as well as a comprehensive list of specific adverse effects. We pooled outcomes at the endpoint preferably closest to one year. We evaluated the certainty of the evidence using the GRADE approach.We included 25 RCTs, of which 22 studies provided data with 2635 participants (average age 38.4 years old). The median study sample size was 60 participants (ranging from 18 to 466 participants) and length was 37 weeks (ranging from 12 weeks to 2 years). There were variations in the dose reduction strategies in terms of speed of reduction (i.e. gradual in about half of the studies (within 2 to 16 weeks) and abrupt in the other half), and in terms of degree of reduction (i.e. median planned reduction of 66% of the dose up to complete withdrawal in three studies). We assessed risk of bias across outcomes predominantly as some concerns or high risk. No study reported data on the number of participants with a clinically important change in quality of life or functioning, and only eight studies reported continuous data on scales measuring quality of life or functioning. There was no difference between dose reduction and continuation on scales measuring quality of life (standardised mean difference (SMD) -0.01, 95% confidence interval (CI) -0.17 to 0.15, 6 RCTs, n = 719, I

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To assess the effects of adding cognitive behavioural therapy to standard care for people with a first episode of schizophrenia.

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To examine the effects and safety of reducing antipsychotic polypharmacy compared to maintaining people with schizophrenia on the same number of antipsychotics. To examine factors of reduction of polypharmacy such as the number of antipsychotics that are withdrawn and whether the reduction of polypharmacy was compensated by increasing the dose of the remaining antipsychotics.

Psychological treatments are increasingly regarded as useful interventions for schizophrenia. However, a comprehensive evaluation of the available evidence is lacking and the benefit of psychological interventions for patients with current positive symptoms is still debated. The present study aimed to evaluate the efficacy, acceptability and tolerability of psychological treatments for positive symptoms of schizophrenia by applying a network meta-analysis approach, that can integrate direct and indirect comparisons. We searched EMBASE, MEDLINE, PsycINFO, PubMed, BIOSIS, Cochrane Library, World Health Organization's International Clinical Trials Registry Platform and ClinicalTrials.gov for randomized controlled trials of psychological treatments for positive symptoms of schizophrenia, published up to January 10, 2018. We included studies on adults with a diagnosis of schizophrenia or a related disorder presenting positive symptoms. The primary outcome was change in positive symptoms measured with validated rating scales. We included 53 randomized controlled trials of seven psychological interventions, for a total of 4,068 participants receiving the psychological treatment as add-on to antipsychotics. On average, patients were moderately ill at baseline. The network meta-analysis showed that cognitive behavioural therapy (40 studies) reduced positive symptoms more than inactive control (standardized mean difference, SMD=-0.29; 95% CI: -0.55 to -0.03), treatment as usual (SMD=-0.30; 95% CI: -0.45 to -0.14) and supportive therapy (SMD=-0.47; 95% CI: -0.91 to -0.03). Cognitive behavioural therapy was associated with a higher dropout rate compared with treatment as usual (risk ratio, RR=0.74; 95% CI: 0.58 to 0.95). Confidence in the estimates ranged from moderate to very low. The other treatments contributed to the network with a lower number of studies. Results were overall consistent in sensitivity analyses controlling for several factors, including the role of researchers' allegiance and blinding of outcome assessor. Cognitive behavior therapy seems to be effective on positive symptoms in moderately ill patients with schizophrenia, with effect sizes in the lower to medium range, depending on the control condition.

Objective Corrected QT (QTc) interval prolongation is often associated with use of first-generation antipsychotics (FGAs). However, other factors require appropriate consideration, including age and gender, the role of other known medications associated with QTc prolongation, and severe comorbid conditions, such as co-occurring alcohol abuse/dependence. We aimed to study potential mediating roles of different, related, candidate variables on QTc. Methods We capitalized on data from a large (N = 2366), cross-sectional, national survey, the STAR Network QTc study, using a representative sample of people taking FGAs, and recruited from mental health services across Italy. Results About one-third of the sample was treated with FGAs, and almost one-tenth of the subjects took a different, additional, drug known to cause QTc prolongation. Our findings confirmed that there is an impact from FGAs, age, gender, alcohol misuse, and concurrent risky drugs on QTc. However, comorbid alcohol abuse/dependence and concurrent risky drugs did not mediate the effect of FGAs on QTc. Conclusions Our findings showed that FGAs, concurrent risky drugs, and alcohol use disorders prolonged QTc. FGAs had a direct effect on QTc, confirming the need for clinicians to monitor a risk that could lead to sudden unexplained death. Copyright © 2016 John Wiley & Sons, Ltd.

Root essential oil of Pulicaria mauritanica Coss. (Asteraceae) collected from western Algeria was analysed using a combination of chromatographic (CC, GC/FID, GC(RI)] and spectroscopic [GC–MS, 13C-NMR] techniques. Thirty-eight compounds accounting for 90.4% of the whole composition were identified. The oil composition was dominated by thymyl derivatives (2,5-dimethoxy-p-cymene (37.2%), 6-methoxythymyl isobutyrate (14.2%), 10-isobutyryloxy-8,9-dehydrothymyl isobutyrate (4.8%) and thymyl isobutyrate (3.1%)), as well as by neryl isobutyrate (11.1%). A new natural compound was isolated and the structure was elucidated as 1S,2S,5S,8S-modhephan-3-one (relative stereochemistry). Copyright © 2014 John Wiley & Sons, Ltd.

Polyalthia longifolia produces sesquiterpene-rich essential oils (EOs) whose compositions varied substantially from sample to sample depending on the origin of the plant (Nigeria and Vietnam). Nothing is known about the phytochemistry of Ivoirian P. longifolia. The aim of the present study was to characterize Ivoirian P. longifolia through the chemical composition of the leaf oil and to develop a strategy that allows the identification of minor oxygenated sesquiterpenes whose MS data are not compiled in commercial or laboratory-constructed MS libraries. The EO was submitted to gas chromatography (GC) retention index (RI), GC-mass spectrometry (MS) and 13C nuclear magnetic resonance (NMR) analysis. Then hydrocarbons and oxygenated components were separated and the oxygenated fraction was chromatographed on silica gel. The fractions were analysed by GC(RI) and 13C NMR. Seventy compounds accounting for 91.8% of the EO were identified. Sesquiterpene hydrocarbons, (E)-β-caryophyllene (27.8%), α-zingiberene (20.0%) and allo-aromadendrene (15.0%), were the major components. Various oxygenated sesquiterpenes whose MS data were not compiled in commercial and laboratory-made MS libraries were identified by comparison of their chemical shift values in the spectrum of the fraction of CC with those reported in the literature and compiled in a laboratory-constructed 13C NMR data library. The composition of the investigated Ivoirian P. longifolia oil sample presented similarities and differences with Nigerian and Vietnamese oils. Combined analysis of Ivoirian P. longifolia EO by chromatographic and spectroscopic techniques including 13C NMR without isolation of the components, appeared particularly efficient to identify minor components of EOs, whose MS spectra are insufficiently differentiated or MS data are not compiled in commercial and lab-constructed MS libraries. Copyright © 2014 John Wiley & Sons, Ltd.

Introduction Germacrenes A–C are secondary metabolites produced by various plants. They are sesquiterpene hydrocarbons bearing the (E,E)-1,5-cyclodecadiene structure known to undergo thermal rearrangement through a [3.3]-sigmatropic reaction. Such a rearrangement was evidenced by comparing the contents of a given germacrene and the corresponding elemene calculated by GC-flame ionisation detection (FID) with the relative intensities of the signals of both molecules in the 13C-NMR spectrum of the mixture, recorded at room temperature. Objective To develop a protocol to identify and quantify germacrenes A, B and C and in parallel the corresponding elemenes, using a combination of GC-FID and 13C-NMR and then provide a correct analysis of Cleistopholis patens essential oils. Methods The essential oil was submitted to GC-FID, GC-retention index, GC–MS and 13C-NMR analyses. The relative percentages of every couple of germacrene and elemene measured by GC-FID were summed. Then, the relative ratio of the mean intensities of the signals of the protonated carbons of a given germacrene and the corresponding elemene was calculated. The contents of both compounds were obtained by combining GC-FID and 13C-NMR data. Results The true content of germacrene A/β-elemene, germacrene B/γ-elemene and germacrene C/δ-elemene in leaf and root oils from C. patens was evaluated by combination of GC-FID and 13C-NMR data. Correct analysis of the essential oils was provided. Conclusion Combined analysis of essential oil including 13C-NMR without isolation of the components, appeared really efficient to identify and quantify germacrene isomers and in parallel elemene isomers in essential oils. Copyright © 2013 John Wiley & Sons, Ltd.

The composition of 55 samples of essential oil isolated from the aerial parts of wild growing Myrtus communis L. harvested in 16 locations from East to West Algeria were investigated by GC (determination of retention indices) and (13) C-NMR analyses. The essential oils consisted mainly of monoterpenes, α-pinene (27.4-59.2%) and 1,8-cineole (6.1-34.3%) being the major components. They were also characterized by the absence of myrtenyl acetate. The compositions of the 55 oils were submitted to k-means partitioning and principal component analysis, which allowed the distinction of two groups within the oil samples, which could be subdivided into two subgroups each. Groups I (78% of the samples) and II were differentiated on the basis of the contents of α-pinene, linalool, and linalyl acetate. Subgroups IA and IB could be distinguished by their contents of α-pinene and 1,8-cineole. Subgroups IIA and IIB differed substantially in their contents of 1,8-cineole and limonene. All the samples contained 3,3,5,5,8,8-hexamethyl-7-oxabicyclo[4.3.0]non-1(6)-ene-2,4-dione (up to 4.9%).

The genus Myrtus L. (Myrtaceae family) comprises two species, Myrtus communis L. (known as common myrtle) growing wild all around the Mediterranean basin and Myrtus nivellei Batt. and Trab. (known as Saharan myrtle), found in central Sahara. Only one country, Algeria, hosts both species, M. communis in the North and M. nivellei in the South. The aim of this review was to collect, summarize, and compare the main results reported relative to the essential oils isolated from aerial parts of both species: botanical aspects, habitat, traditional use, chemical composition, new compounds, antimicrobial activity, antioxidant activity, anti-inflammatory effect, and insecticidal activity. Both essential oils have potential applications in human health.

Myrtus communis L. grows wild all around the Mediterranean basin and on the islands. Myrtle leaf essential oil has a characteristic pleasant odour although various compositions, which differ by the content of monoterpene esters, have been reported. Fractionation of an essential oil sample from Corsica, followed by analysis of the chromatographic fractions by GC (RI) and 13 C NMR allowed the identification of four C8-C10 esters, first identified 20 years ago in a Spanish essential oil sample and since that time very scarcely reported, despite the tremendous amount of work carried out on the composition of myrtle leaf essential oil. Therefore, the composition of 63 samples of M. communis L. leaf essential oil isolated from myrtle growing wild in various Mediterranean countries (Corsica, Sardinia, Portugal, Morocco, Algeria and Tunisia) has been investigated by GC(RI) and 13 C NMR and the four C8-C10 esters have been identified in all the samples. The occurrence of these esters merits great attention, since they contribute to the pleasant odour of the myrtle essential oil. In parallel, 3,3,5,5,8,8-hexamethyl-7-oxabicyclo[4.3.0]non-1(6)-ene-2,4-dione has been identified in all the samples.

Introduction In the course of on-going work on the characterisation of aromatic plants from the Ivory Coast we investigated the composition of the root oil from Xylopia aethiopica. Objectives The aim of this work was to investigate the chemical composition of X. aethiopica root oil and elucidate the structure of two new compounds. Methodology Analysis of the essential oil was carried out using a combination of chromatographic (CC, GC with retention indices) and spectroscopic techniques (MS, 13C-NMR, 2D-NMR). Results Twenty seven components, accounting for 95.6% of the whole composition, were identified including various compounds for which spectroscopic data were absent on commercial computerised MS libraries. Three compounds are reported for the first time as natural compounds and the structure of two new compounds, 4,4-dimethyl-2-vinylcyclohexene and endo-5-methoxy-3-patchoulene, has been elucidated using extensive two-dimensional NMR spectroscopy. Conclusion The composition of X. aethiopica root oil is dominated by two dimethylvinylcyclohexene isomers. It differs drastically from the composition of leaf and fruit oils of the same plant. The combination of analytical techniques appeared crucial for a fruitful analysis. Copyright © 2012 John Wiley & Sons, Ltd.

Twenty-three resin samples have been obtained by tapping from individual Pinus pinaster adult trees grown in Corsica and submitted to acido-basic partition. Identification and quantitative determination of resin acids has been carried out using 13 C-NMR spectroscopy following a method developed by our group. The main components were dehydroabietic acid (up to 37.6 %), levopimaric acid (up to 35.5 %) and abietic acid (up to 24.7 %). A lignan, pinoresinol, has been identified in some samples. Within the 23 compositions, submitted to k-means analysis and Principal Component Analysis, two clusters have been perfectly differentiated, whose compositions were dominated by dehydroabietic acid (Group I, M=23.5 %, SD=6.3) and levopimaric acid (Group II, M=21.2 %; SD=6.2), respectively. Both compositions have been observed in the three locations of harvest.

Introduction The study of taxanes is a hot topic worldwide because of their potential activity against cancer. Analysis of taxanes in extracts of various Taxus species is generally achieved using HPLC. Objective The aim of the current work was to identify taxanes in different fractions of extracts from Taxus baccata L. using the computer-aided analysis of their 13C-NMR spectra. Methodology A computerised procedure, based on 13C-NMR spectroscopy using literature data, has been developed in order to identify taxoids in natural mixtures. Leaves and twigs of T. baccata were extracted with various solvents and the extracts were fractionated according to rapid fractionation schemes described in the literature. Results The computer-assisted analysis of the 13C-NMR spectra of the fractions of chromatography led to the identification of 16 taxanes belonging to the taxine, taxicine, taxinine and taxuspine families. Conclusion It has been shown that 13C-NMR is a powerful alternative tool for the identification of taxanes in extracts of leaves and twigs of various Taxus species after a rapid fractionation step. Copyright © 2009 John Wiley & Sons, Ltd.

The composition of 46 samples of needle oil of maritime pine (Pinus pinaster Ait.) from Corsica was investigated by gas chromatography (GC) in combination with retention indices, GC–MS and 13C-NMR. Sixty compounds, accounting for 82.9–97.0% of the oil, were identified. The oils consisted mainly of mono-, sesqui- and diterpene hydrocarbons, especially α-pinene (6.4–29.4%), (E)-β-caryophyllene (4.4–19.9%), germacrene D (1.7–21.4%) and abieta-7,13-diene (6.8–34.2%). Although the composition varied substantially from sample to sample, k-means partitioning and principal component analysis (PCA) of the compositional data suggested the occurrence of only one group within the 46 individual samples. The composition dominated by diterpene hydrocarbons (up to 61%) is reported for the first time. Copyright © 2008 John Wiley & Sons, Ltd.

The chemical composition of the volatile oil extracted from aerial parts (twigs, leaves and flowers) of Michelia foveolata growing wild in Vietnam was investigated by combination of column chromatography, GC (retention indices), GC–MS and 13C-NMR spectroscopy. Fifty-eight components were identified, with sabinene (32.4%) and terpinen-4-ol (13.7%) as the main constituents. The essential oil was tested against 11 bacteria using the agar disc diffusion method, and exhibited a significant antibacterial activity against Salmonella enterica, Staphylococcus epidermidis, Staphylococcus aureus and Bacillus cereus (MICs = 2–4 µl/ml). Copyright © 2007 John Wiley & Sons, Ltd.

The essential oil of Doronicum corsicum L. (Asteraceae), an endemic species from Corsica, has been studied by GC, GC–MS(EI and CI), 1H- and 13C-NMR; 129 components were identified, representing 80.4% of the total amount. The essential oil was dominated by sesquiterpene hydrocarbons (38.2%) and oxygenated monoterpenes (36.7%). The major components were modhephene (11.6%), (E)-β-caryophyllene (9.8%), 10-isobutyryloxy-8,9-epoxythymyl angelate (9.9%) and thymyl angelate (8.7%). The structures of the two thymol derivatives, the 13C-NMR data of four other thymol derivatives and the chemical composition of the essential oil of D. corsicum were reported for the first time. Copyright © 2007 John Wiley & Sons, Ltd.

The composition of 27 samples of berry oil and 54 samples of leaf oil of Juniperus oxycedrus ssp. oxycedrus from Corsica was investigated by GC, GC-MS and 13C-NMR. The main constituents were terpene hydrocarbons, especially alpha-pinene, myrcene and germacrene D in the oils from berries and alpha-pinene, beta-phellandrene and Delta3-carene in the oils from leaves. The results of the analyses were submitted to k-means partitioning and principal component analysis, which allowed the distinction of two compositions in the berry oils (differentiated by the contents of alpha-pinene, myrcene and germacrene D) and in the leaf oils (differentiated by the contents of alpha-pinene, beta-phellandrene and Delta3-carene). (Z)-6-Pentadecen-2-one, an unusual alkenone present in several samples of leaf oil, was identified using 13C-NMR spectroscopy. Copyright © 2005 John Wiley & Sons, Ltd.

The root oil of Fokienia hodginsii from Vietnam was submitted, after fractionation over silica gel, to a combined analysis by GC-RI, GC-MS and 1 3 C-NMR. Forty hydrocarbons and 19 oxygenated compounds, mostly sesquiterpenes, were identified. (E)-Nerolidol and fokienol were the major components.

The chemical composition of Enhydra fluctuans essential oil from Vietnam was investigated by GC/retention indices and carbon-13 NMR spectroscopy. Myrcene, limonene, trans- and cis-dihydroperillaldehydes were the major components. This is the first report of the two isomers in nature. Copyright © 2000 John Wiley & Sons, Ltd.