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Apolipoprotein E (APOE) E4 is the main genetic risk factor for Alzheimer’s disease (AD). Due to the consistent association, there is interest as to whether E4 influences the risk of other neurodegenerative diseases. Further, there is a constant search for other genetic biomarkers contributing to these phenotypes, such as microtubule-associated protein tau (MAPT) haplotypes. Here, participants from the Ontario Neurodegenerative Disease Research Initiative were genotyped to investigate whether the APOE E4 allele or MAPT H1 haplotype are associated with five neurodegenerative diseases: (1) AD and mild cognitive impairment (MCI), (2) amyotrophic lateral sclerosis, (3) frontotemporal dementia (FTD), (4) Parkinson’s disease, and (5) vascular cognitive impairment.
Genotypes were defined for their respective APOE allele and MAPT haplotype calls for each participant, and logistic regression analyses were performed to identify the associations with the presentations of neurodegenerative diseases.
Our work confirmed the association of the E4 allele with a dose-dependent increased presentation of AD, and an association between the E4 allele alone and MCI; however, the other four diseases were not associated with E4. Further, the APOE E2 allele was associated with decreased presentation of both AD and MCI. No associations were identified between MAPT haplotype and the neurodegenerative disease cohorts; but following subtyping of the FTD cohort, the H1 haplotype was significantly associated with progressive supranuclear palsy.
This is the first study to concurrently analyze the association of APOE isoforms and MAPT haplotypes with five neurodegenerative diseases using consistent enrollment criteria and broad phenotypic analysis.
Metacognition refers to the ability to evaluate and control our cognitive processes. While studies have investigated metacognition in schizophrenia and clinical high risk for psychosis (CHR), less is known about the potential mechanisms which result in metacognitive deficits.
We aimed to investigate whether neurocognitive functions including attention, working memory, verbal learning and executive functions predicted the tendency to focus on one’s thoughts (cognitive self-consciousness) and beliefs in the efficacy of one’s cognitive skills (cognitive confidence).
Participants (130 CHR individuals) were recruited as part of the multi-site PREDICT study. They were assessed using the Metacognitions Questionnaire (MCQ) as well as measures of executive function (WCST), attention (N-Back), working memory (LNS) and verbal learning (AVLT).
Cognitive competence was negatively correlated with N-Back while cognitive self-consciousness was positively correlated with N-Back and LNS. Linear regression analysis with N-Back, AVLT, LNS and WCST as predictors showed that neurocognition significantly predicted cognitive self-consciousness, with N-Back, LNS and WCST as significant predictors. The model accounted for 14% of the variance in cognitive self-consciousness. However, neurocognition did not result in a significant predictive model of cognitive competence.
Neurocognition was associated with an increased focus on one’s thoughts, but it was not associated with higher confidence in one’s cognitive skills. Neurocognition accounted for less than one-sixth of the variance in metacognition, suggesting that interventions that target neurocognition are unlikely to improve metacognitive abilities.
Increasing the number of quantum bits while preserving precise control of their quantum electronic properties is a significant challenge in materials design for the development of semiconductor quantum computing devices. Semiconductor heterostructures can host multiple quantum dots that are electrostatically defined by voltages applied to an array of metallic nanoelectrodes. The structural distortion of multiple-quantum-dot devices due to elastic stress associated with the electrodes has been difficult to predict because of the large micrometer-scale overall sizes of the devices, the complex spatial arrangement of the electrodes, and the sensitive dependence of the magnitude and spatial variation of the stress on processing conditions. Synchrotron X-ray nanobeam Bragg diffraction studies of a GaAs/AlGaAs heterostructure reveal the magnitude and nanoscale variation of these distortions. Investigations of individual linear electrodes reveal lattice tilts consistent with a 28-MPa compressive residual stress in the electrodes. The angular magnitude of the tilts varies by up to 20% over distances of less than 200 nm along the length of the electrodes, consistent with heterogeneity in the metal residual stress. A similar variation of the crystal tilt is observed in multiple-quantum-dot devices, due to a combination of the variation of the stress and the complex electrode arrangement. The heterogeneity in particular can lead to significant challenges in the scaling of multiple-quantum-dot devices due to differences between the charging energies of dots and uncertainty in the potential energy landscape. Alternatively, if incorporated in design, stress presents a new degree of freedom in device fabrication.
A stress-strain relationship for copper in the plastic region has been determined by examining the influence of the applied stresses on the grain orientation of shear-formed specimens. Instrumentation was developed to permit accurate grain-orientation analysis of a large specimen by X-ray diffraction without the necessity for deformation or destruction of the specimen.
The Endangered Asian elephant Elephas maximus comes into widespread conflict with agrarian communities, necessitating active management. The species’ distribution is of primary importance for management planning. However, data-based countrywide distribution maps have not been available for any of the 13 Asian elephant range states. We conducted a 5 × 5 km grid-based questionnaire survey in Sri Lanka to produce an island-wide elephant distribution map. Elephants occur over 59.9% of Sri Lanka and people are resident in 69.4% of elephant range, indicating the challenge of separating people and elephants at a landscape scale. Elephants in Sri Lanka have lost 16.1% of their range since 1960 but their current distribution remains largely contiguous. We found the range of adult males was 15.1% greater, and less seasonal, than that of herds, possibly because males have a higher tolerance for conflict with people. The distribution of conflict coincided with the co-occurrence of humans and elephants. We conclude that a human–elephant coexistence model is the only viable option for effectively mitigating human–elephant conflict and conserving elephants in Sri Lanka. The findings are currently being used to effect a paradigm change in elephant conservation and management in the country.
The paper presents the results of a study on propagation and focusing of high-intensity pulsed ion beams, produced by a self-magnetically insulated diode of semi-cylindrical geometry at the TEMP-6 accelerator (120 ns, 200–250 kV). We examined the space-charge neutralization of the beam, the energy density in the focus, the divergence of the beam, and its shot-to-shot displacement in the focal plane. It is found that the concentration of low-energy electrons in the beam is 1.3–1.5 times higher than the concentration of ions. We observed additional ion focusing by its own space charge. With an increase in the density of the net negative (electrons and ions) charge of the beam from 3.6 to 9 µC/cm2, the total divergence (the sum of the beam divergence in the vertical and horizontal planes) decreases from 11.4 to 4.5°. It leads to an increase in the energy density in the focus from 4 up to 10–12 J/cm2. To increase the electrons concentration in the beam, a metal grid installed in the ion beam transport region was used.
Autism spectrum disorder (ASD) and obsessive–compulsive disorder (OCD) are neurodevelopmental disorders with considerable overlap in terms of their defining symptoms of compulsivity/repetitive behaviour. Little is known about the extent to which ASD and OCD have common versus distinct neural correlates of compulsivity. Previous research points to potentially common dysfunction in frontostriatal connectivity, but direct comparisons in one study are lacking. Here, we assessed frontostriatal resting-state functional connectivity in youth with ASD or OCD, and healthy controls. In addition, we applied a cross-disorder approach to examine whether repetitive behaviour across ASD and OCD has common neural substrates.
A sample of 78 children and adolescents aged 8–16 years was used (ASD n = 24; OCD n = 25; healthy controls n = 29), originating from the multicentre study COMPULS. We tested whether diagnostic group, repetitive behaviour (measured with the Repetitive Behavior Scale-Revised) or their interaction was associated with resting-state functional connectivity of striatal seed regions.
No diagnosis-specific differences were detected. The cross-disorder analysis, on the other hand, showed that increased functional connectivity between the left nucleus accumbens (NAcc) and a cluster in the right premotor cortex/middle frontal gyrus was related to more severe symptoms of repetitive behaviour.
We demonstrate the fruitfulness of applying a cross-disorder approach to investigate the neural underpinnings of compulsivity/repetitive behaviour, by revealing a shared alteration in functional connectivity in ASD and OCD. We argue that this alteration might reflect aberrant reward or motivational processing of the NAcc with excessive connectivity to the premotor cortex implementing learned action patterns.
There is contradictory evidence regarding the effect on the gas production (GP) profile of a feed if the incubation medium is shaken during the fermentation. In experiments conducted by Theodorou et al. (personal communication), there was no effect of shaking on the rate of gas production (when the medium was shaken after a recording). However, when buffer solutions (containing no substrate) were continually shaken, there was an effect on the volume of gas produced (Rymer et ai., 1998). The objectives of this experiment were therefore to determine whether die time of shaking affected the GP profile, and whether there was any significant difference between laboratories in this observation.
The use of a syringe (manual method) to measure gas production is time consuming and inaccurate. In addition the time taken prevents frequent measurements and therefore does not allow gas production kinetics to be fully described. According to Boyle's Law, gas volume corrected for temperature, is directly related to pressure. A simple, semi-automatic system recording of gas pressure and equations to estimate volume, was therefore developed.
Data for this work came from a study which compared rumen liquor and faeces as sources of inoculum using the method of Theodorou et al. (1994). Six substrates (wheat straw, hay, soyabean meal, wheat starch, maize starch, and potato residue) were utilized. Gas pressure readings (observations = 1187) were measured using a hand-held pressure transducer with an LED readout. Interfaced to a computer using a Mini-Pod 300 (AD converter). MS-Visual Basic (Microsoft) was used to convert the mini-pod readings and automatically enter them into an Excel spreadsheet. Gas volume was measured using a syringe to remove the gas produced until the readout indicated zero.
A previous study (Mauricio et al., 1998) with 12 forage substrates (straw, hay and dried grasses) showed a high correlation between rumen liquor and faeces for total gas production and in vitro organic matter digestibility (OMD). However parameters estimated using faecal inoculum were generally lower man when using rumen liquor. To confirm this observation, a second study was conducted using maize silage and silages made from maize plant fractions.
The experiment was conducted using a range of forages with accurately predetermined OMD values (ADAS) to compare rumen liquor (RL) and faeces (FA) as sources of inocula in the pressure transducer technique (PTT) (Theodorou et al., 1994). Gas production results were examined in relation to OMD determined in vitro (PTT, Tilley and Terry) and in vivo.
The quantity of gas accumulated in the in vitro fermentation technique (e.g. Theodorou et al., 1994) results from gaseous end-products of substrate fermentation, lysis of rumen microorganisms and CO2 released when VFA are neutralised by the carbonate-buffered medium (Beuvink and Spoelstra, 1992). However the quantity of gas produced from this acid-buffer interaction is not directly related to substrate fermentation and therefore needs to be quantified if gas evolution from substrate fermentation is to be estimated. This study examined gas release following the addition of acetic acid to a bicarbonate buffered medium and used a Gompertz equation to describe both the rate and total volume produced.
An abattoir study was carried out between May and October 2016 to determine the parasitic causes of organ condemnation during meat inspection and to evaluate the attendant financial losses in Fako abattoirs, in the South-West region of Cameroon. Organs (liver, lungs, heart, tongue, kidney, spleen and intestine) were examined at meat inspection following standard procedures and the financial loss was estimated by considering the total weight of condemned organs and the price per kilogram of marketable organs, obtained from the local market. The organs of 1472 cattle were examined, of which 357 (24.38%) were condemned. The organs condemned because of parasitic infestations were the liver (333) and small intestine (24), and the infections were caused by flukes of Fasciola sp. and proglottids of Moniezia sp., respectively. Hydatid cysts and cysticerci were absent. The prevalence of fasciolosis and monieziosis was 22.62% and 1.63%, respectively. Condemnation deprived the region of 665.457 kg of meat, with an associated financial loss of CFA 1,330,902 (USD 2505), during the study period. Parasitic diseases worsen the food insecurity situation as they result in the withdrawal of a considerable amount of meat from the food chain. Fasciolosis, the leading parasitic cause of meat condemnation in Fako, is also zoonotic. It is therefore important that effective control measures are implemented countrywide against this parasitosis.
Traditional diagnostic capabilities (serology and culture) are not enough to monitor the poultry infections efficiently. For effective control of poultry infections, a regular program incorporating simple and cost-effective molecular diagnostics is necessary. On this rationale, it is possible to present working molecular diagnostic technology that would work equally well in field as well as in the laboratory. Recently, the loop-mediated isothermal amplification (LAMP) assay has emerged as simple and inexpensive diagnostic tool for the molecular detection of various animal pathogens. To perform LAMP, no specialised instruments (e.g. thermal cycler) are required, permitting its use in developing countries. Various reliable LAMP assays have been reported for the detection of different poultry pathogens. However, still there is a need to improve the sensitivity, specificity, reproducibility, user-friendliness, delivery to end-user and affordability of LAMP assays. This article reviews current LAMP assays available for the molecular detection of important viral, bacterial and protozoan pathogens of poultry. It focuses on the various aspects of LAMP for the diagnosis of important poultry pathogens based upon pathogen type, specimen, target genes, LAMP primer types, detection limits, fluorescent detectors and LAMP chemistry used. This paper provides updates on principle, instrumentation, basic methodology, quantification capability, reagents and kits used currently in performing LAMP.
In this paper, the results of an experimental investigation of dust formation in a pulsed plasma accelerator, which is formed due to the interaction of a pulsed plasma flow with the candidate material of the thermonuclear reactor, are presented. Dynamic and optical properties of a pulsed plasma flow are considered. The results of the synergetic analysis by the Raman spectrometer of the target surface after irradiation with plasma are also presented. It was revealed that after interaction with the plasma, the surface of the graphite target becomes amorphous. Materials with fractal surfaces, similar to the materials formed in tokamaks under the action of erosion, were obtained experimentally. Using a high-speed camera Phantom v2512 video shooting of the plasma beam was carried out, during which it was revealed that the pulsed plasma beam has a speed of about 23 km/s.