731 research outputs found
Behavioural characteristics in externalising children with low and elevated risk for dental caries
AIM: To compare two groups of children with externalising behaviour problems, having low and elevated caries risk, respectively. Those parameters were assessed in relation to behavioural characteristics and family structure, and to compare the caries risk assessment and gender differences in relation to children in general in the Region of Västra Götaland, Sweden. METHODS: Families (228) with children, aged 10-13 years, participating in parent training programmes, were recruited. Parents provided information through questionnaires regarding parental knowledge and monitoring, family warmth and conflict and family structure. Children’s behavioural characteristics, based on the Strength and Difficulties Questionnaire and the Disruptive Behaviour Disorder rating scale, were used as outcome. Data about caries risk assessment were obtained from dental records. RESULTS: Children in the elevated caries risk group showed higher mean values for conduct problems as well as impulsivity. Parents of the children in the elevated caries risk group reported more parental solicitation and less family conflicts. Children with an elevated caries risk lived more often in households with more than two children and had more often a father from a non-Nordic country. CONCLUSION: There were statistically significant more children with an elevated caries risk in the study group compared to children in general in the Region of Västra Götaland, both totally and within gender. Differences were observed with regard to behavioural characteristics in externalising children with an elevated risk for caries. Increased knowledge regarding behavioural characteristics in externalising children is an important parameter to be considered in caries risk assessment
Uncertainty analysis of a test bed for calibrating voltage transformers vs.Temperature
The paper addresses the evaluation of the uncertainty sources of a test bed system for calibrating voltage transformers vs. temperature. In particular, the Monte Carlo method has been applied in order to evaluate the effects of the uncertainty sources in two different conditions: by using the nominal accuracy specifications of the elements which compose the setup, or by exploiting the results of their metrological characterization. In addition, the influence of random effects on the system accuracy has been quantified and evaluated. From the results, it emerges that the choice of the uncertainty evaluation method affects the overall study. As a matter of fact, the use of a metrological characterization or of accuracy specifications provided by the manufacturers provides respectively an accuracy of 0.1 and 0.5 for the overall measurement setup
The Incremental Cooperative Design of Preventive Healthcare Networks
This document is the Accepted Manuscript version of the following article: Soheil Davari, 'The incremental cooperative design of preventive healthcare networks', Annals of Operations Research, first published online 27 June 2017. Under embargo. Embargo end date: 27 June 2018. The final publication is available at Springer via http://dx.doi.org/10.1007/s10479-017-2569-1.In the Preventive Healthcare Network Design Problem (PHNDP), one seeks to locate facilities in a way that the uptake of services is maximised given certain constraints such as congestion considerations. We introduce the incremental and cooperative version of the problem, IC-PHNDP for short, in which facilities are added incrementally to the network (one at a time), contributing to the service levels. We first develop a general non-linear model of this problem and then present a method to make it linear. As the problem is of a combinatorial nature, an efficient Variable Neighbourhood Search (VNS) algorithm is proposed to solve it. In order to gain insight into the problem, the computational studies were performed with randomly generated instances of different settings. Results clearly show that VNS performs well in solving IC-PHNDP with errors not more than 1.54%.Peer reviewe
Effects of thermal cycles on interfacial pressure in MV cable joints
The use of medium voltage cable joints is mandatory when dealing with power cable faults and the installation of new lines. However, such an accessory is among the top causes of faults among the grid. To this purpose, one of the quantities monitored to understand the causes of such faults is the interfacial pressure between the insulating layers of the cable joint. In this work, the interfacial pressure between Cross-linked polyethylene (XLPE) and silicon rubber has been evaluated when the cable joint experiences thermal cycles. From the results, the pressure variation caused by the thermal cycles is demonstrated. Such a phenomenon may be connected to the generation of voids and weak spots that accelerate cable joint ageing. Therefore, proper comments and conclusions are drawn
Polymorphism analysis of the CTLA-4 gene in paracoccidioidomycosis patients
The CTLA-4 protein is expressed in activated T cells and plays an essential role in the immune response through its regulatory effect on T cell activation. Polymorphisms of the CTLA-4 gene have been correlated with autoimmune, neoplastic and infectious illnesses. This work aimed to verify possible associations between single nucleotide polymorphisms (SNPs) in CTLA-4, -318C/T in the promoter and +49A/G in exon 1 and paracoccidioidomycosis (PCM) caused by Paracoccidioides brasiliensis. For this purpose, 66 chronic form PCM patients and 76 healthy controls had their allele, genotype and haplotype frequencies determined. The genetic admixture structure of the patients and controls was evaluated to eliminate ancestral bias. The comparison of frequencies indicated no significant differences between patients and controls that could link the SNPs to PCM. Groups were admixture matched with no difference observed in population ancestry inference, indicating that the absence of association between CTLA-4 polymorphisms and PCM could not be attributed to ancestral bias. This study showed that there was no association between the CTLA-4 SNPs -318 and +49 and the resistance or susceptibility to PCM
Role of Diffusion-Weighted MRI (DWI-MRI) in the Diagnosis of Brain Complications caused by Heroin Substance Abuse
Background: Magnetic resonance imaging (MRI) offers higher diagnostic accuracy for brain lesions caused by heroin abuse compared to compute tomography (CT) scan. These lesions have a low signal on T1-weighted (T1W) images and a high signal on T2-weighted (T2W) and fluid-attenuated inversion recovery (FLAIR) images. This study aimed to evaluate the role of diffusion-weighted MRI (DWI-MRI) in heroin addicts.Methods: This cross-sectional study was conducted on 20 patients with heroin addiction (vapor inhalation/injection) referring to Imam Reza Hospital of Mashhad, Iran. Patients in whom heroin abuse was only cause of consciousness, loss and neurological symptoms were enrolled in this study. Demographic data of the patients were recorded, including MRI, FLAIR, T1W and T2W images. In addition, DWI of axial and sagittal sections of the brain was performed in the following sequences.Results: In this study, mean age of patients was 40.15±7.673 years, and 95% of patients were male. The most common mode of heroin use was inhalation, and mean duration of addiction was 5.48±3.393 years. Mean daily intake of heroin was 13.4±15.30 grams, and mean duration of heroin abuse was 10.3 and 4.6 years in patients with and without MRI changes, respectively. A significant correlation was observed between MRI changes and duration of heroin use (r=0.721) (p=0.001). In addition, a significant correlation was observed between MRI changes and daily intake of heroin (p=0.006).Conclusion: According to the results of this study, brain lesions caused by heroin abuse have a low signal on T1W images and a high signal on T2W and FLAIR images. Therefore, it could be concluded that heroin intake has significant effects on the brain of users
Correcting a mistake: Limnophyes stagnum Namayandeh, Guerra & Ram, 2024 is not conspecific with Limnophyes sp. 14ES
In this communication, we report on correcting DNA barcoding records of Limnophyes stagnum Namayandeh, Guerra & Ram, 2024. The five sequences we submitted to BOLD and published in Namayandeh et al. (2024) under L. stagnummatch the CO1 sequences of Limnophyes sp. 14ES and the two species are not conspecific. Both species were collected from the type locality of L. stagnum but at different times with a misassumption that both species represent a single taxon. We have corrected our records in BOLD, replacing the names of the five sequences with Limnophyes sp. 14ES. Additionally, we obtained and uploaded a single CO1 sequence of L. stagnum in BOLD and incorporated it into new molecular analyses reported here. Based on our results, the closest sequences to L. stagnum were those of Limnophyes natalensis (Kieffer, 1914). The minimum K2P distance of L. stagnum with L. natalensis was 10.0% (average 11.4%), large enough to support the delimitation of L. stagnum sp. nov. from L. natalensis. Further discussion on the morphological differences of the two species and those of L. stagnum and Limnophyes sp. 14ES are provided
Visualizing chemical states and defects induced magnetism of graphene oxide by spatially-resolved-X-ray microscopy and spectroscopy
[[abstract]]This investigation studies the various magnetic behaviors of graphene oxide (GO) and reduced
graphene oxides (rGOs) and elucidates the relationship between the chemical states that involve
defects therein and their magnetic behaviors in GO sheets. Magnetic hysteresis loop reveals that the
GO is ferromagnetic whereas photo-thermal moderately reduced graphene oxide (M-rGO) and heavily
reduced graphene oxide (H-rGO) gradually become paramagnetic behavior at room temperature.
Scanning transmission X-ray microscopy and corresponding X-ray absorption near-edge structure
spectroscopy were utilized to investigate thoroughly the variation of the C 2p(π*) states that are
bound with oxygen-containing and hydroxyl groups, as well as the C 2p(σ*)-derived states in flat
and wrinkle regions to clarify the relationship between the spatially-resolved chemical states and
the magnetism of GO, M-rGO and H-rGO. The results of X-ray magnetic circular dichroism further
support the finding that C 2p(σ*)-derived states are the main origin of the magnetism of GO. Based
on experimental results and first-principles calculations, the variation in magnetic behavior from GO
to M-rGO and to H-rGO is interpreted, and the origin of ferromagnetism is identified as the C 2p(σ*)-
derived states that involve defects/vacancies rather than the C 2p(π*) states that are bound with
oxygen-containing and hydroxyl groups on GO sheets.[[notice]]補正完
The intersection between knowledge management and organizational learning in tourism and hospitality: A bibliometric analysis
This study aims to investigate the intersection between organizational learning (OL) and knowledge management (KM) in the tourism and hospitality sector by conducting a bibliometric analysis. A total of 628 publications from 293 various sources and 1468 different authors were included in the analysis between 2001 and 2021. Open-source statistical R software was utilized to conduct the bibliometric analysis, specifically, the Bibliometrix R library and the Biblioshiny version. The VOSviewer program was also used to display the keyword co-occurrence network. The findings show that the implication of KM and OL has been widely recognized as critical learning facilitators and as strategic tools for gaining competitive advantage that recognizes opportunities and threats for possible alignment with environmental change. Organizational learning and KM are particularly relevant for sustainable tourism and hospitality solutions, cutting-edge technologies, and organizational service innovations. Four research clusters were identified that provide critical future research paths
Discerning primary versus diagenetic signals in carbonate carbon and oxygen isotope records: An example from the Permian-Triassic boundary of Iran
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordSedimentary successions across the Permian-Triassic boundary (PTB) are marked by a prominent negative carbon isotope excursion. This excursion, found in both fossil (e.g., brachiopod) and bulk carbonate at many sites around the world, is generally considered to be related to a global carbon cycle perturbation. Oxygen isotopes also show a negative excursion across the PTB, but because δ18O is more prone to diagenetic overprint (especially in bulk carbonate), these data are often not used in palaeoenvironmental analyses. In the present study, bulk-rock and brachiopod δ13C and δ18O, as well as conodont δ18O, were analyzed in PTB successions at Kuh-e-Ali Bashi and Zal (NW Iran) in order to evaluate diagenetic overprints on primary marine isotopic signals. The results show that the use of paired C-O isotopes and Mn-Sr concentrations is not sufficient to identify diagenetic alteration in bulk materials, because δ13C-δ18O covariation can be due to environmental factors rather than diagenesis, and Sr/Ca and Mn/Ca ratios can vary as a function of bulk-rock lithology. Comparison of δ13C profiles shows that all bulk carbonate is altered to some degree, although the general bulk-rock trend mimics that of the brachiopod data with a systematic offset of -1.2(±0.4)‰. This suggests that the first-order δ13C trend in bulk carbonate is generally robust but that the significance of small-scale carbon isotope fluctuations is uncertain, especially when such fluctuations are linked to lithologic variation. The PTB interval, which is marked by a low-carbonate 'Boundary Clay' in the study sections, may be especially prone to diagenetic alteration, e.g., via late-stage dolomitization. Comparison of oxygen-isotope profiles for bulk rock and well-preserved fossils (both brachiopods and conodonts) shows that the former are offset by -2.1(±0.4)‰. Diagenetic modeling suggests that these offsets were the product mainly of early diagenesis at burial temperatures of ~50-80°C and water/rock ratios of <10. Authigenic carbonates precipitated during early diagenesis represent a potentially major sink for isotopically light carbon at a global scale that has received relatively little attention to date.TJA thanks the Sedimentary Geology and Paleobiology program of the U.S. National Science Foundation (NSF EAR-1053449), the NASA Exobiology program (NNX13AJ1IG), and the China University of Geosciences—Wuhan (SKL-GPMR program GPMR201301, and SKL-BGEG programBGL21407) for their support. This study was funded by Deutsche Forschungsgemeinschaft (DFG; projects KO1829/12-1, KO1829/12-2 and KO2011/8-1)
- …
