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The new standard computerized reading span test (RST), which is a complex verbal working memory test, was used for the first time in the assessment of verbal working memory capacity (Van den Noort et al., 2008) in two clinical populations.
Sixty participants, divided over three different groups; 20 patients with chronic schizophrenia, 20 patients with chronic depression, and 20 healthy participants, entered the study. The selection of the participants was based on strict inclusion and exclusion criteria. There was no comorbid depression in the patients with schizophrenia, as measured by the BDI-II. A comparison was made between the 3 different groups with respect to their verbal working memory capacity. The new standard computerized RST (Van den Noort et al., 2008) was used.
In this study, in line with previous studies, a significant decrease in verbal working memory capacity and a general slowing down was found in chronic patients with schizophrenia and chronic patients with depression in comparison with healthy participants. In addition, patients with schizophrenia showed a nearly significant higher reading span score but were significantly slower than the chronic patients with depression.
The new standard computerized RST (Van den Noort et al., 2008) is a suitable complex verbal working memory test that could be used for clinical applications, for instance, for the assessment of verbal working memory capacity in patients with chronic schizophrenia and chronic depression.
There is no consensus as to whether magnetic resonance imaging (MRI) should be used as part of the initial clinical evaluation of patients with first-episode psychosis (FEP).
(a) To assess the logistical feasibility of routine MRI; (b) to define the clinical significance of radiological abnormalities in patients with FEP.
Radiological reports from MRI scans of two FEP samples were reviewed; one comprised 108 patients and 98 healthy controls recruited to a research study and the other comprised 241 patients scanned at initial clinical presentation plus 66 healthy controls.
In the great majority of patients, MRI was logistically feasible. Radiological abnormalities were reported in 6% of the research sample and in 15% of the clinical sample (odds ratio (OR) = 3.1, 95% CI 1.26–7.57, χ2(1) = 6.63, P = 0.01). None of the findings necessitated a change in clinical management.
Rates of neuroradiological abnormalities in FEP are likely to be underestimated in research samples that often exclude patients with organic abnormalities. However, the majority of findings do not require intervention.
This study reports the clinical outcomes of head and neck adenoid cystic carcinoma treatment over a 20-year period.
The treatment outcome of 51 head and neck adenoid cystic carcinoma patients treated between 1992 and 2013 were analysed. Patients were stratified into radical treatment and disease control groups.
A total of 40 patients underwent surgery and post-operative radiotherapy. The 10-year disease-specific survival rate was 93 per cent. Eleven patients had tumour recurrence: of these, nine were pulmonary metastases. The 11 patients in the disease control group had a median follow up of 21 months (range, 2–172 months); 5 underwent radical radiotherapy with palliative intent.
There was late tumour recurrence in over 25 per cent of patients. Adenoid cystic carcinoma has a high tendency to relapse even after radical excision and adjuvant therapy. However, definitive radiotherapy should still be considered on an individual basis because it may provide local control and prolong patient survival.
Erythroblastic islands are multicellular clusters in which a central macrophage supports the development and maturation of red blood cell (erythroid) progenitors. These clusters play crucial roles in the pathogenesis observed in animal models of hematological disorders. The precise structure and function of erythroblastic islands is poorly understood. Here, we have combined scanning electron microscopy and immuno-gold labeling of surface proteins to develop a better understanding of the ultrastructure of these multicellular clusters. The erythroid-specific surface antigen Ter-119 and the transferrin receptor CD71 exhibited distinct patterns of protein sorting during erythroid cell maturation as detected by immuno-gold labeling. During electron microscopy analysis we observed two distinct classes of erythroblastic islands. The islands varied in size and morphology, and the number and type of erythroid cells interacting with the central macrophage. Assessment of femoral marrow isolated from a cavid rodent species (guinea pig, Cavis porcellus) and a marsupial carnivore species (fat-tailed dunnarts, Sminthopsis crassicaudata) showed that while the morphology of the central macrophage varied, two different types of erythroblastic islands were consistently identifiable. Our findings suggest that these two classes of erythroblastic islands are conserved in mammalian evolution and may play distinct roles in red blood cell production.
Objectives: One of the most prominent features of schizophrenia is relatively lower general cognitive ability (GCA). An emerging approach to understanding the roots of variation in GCA relies on network properties of the brain. In this multi-center study, we determined global characteristics of brain networks using graph theory and related these to GCA in healthy controls and individuals with schizophrenia. Methods: Participants (N=116 controls, 80 patients with schizophrenia) were recruited from four sites. GCA was represented by the first principal component of a large battery of neurocognitive tests. Graph metrics were derived from diffusion-weighted imaging. Results: The global metrics of longer characteristic path length and reduced overall connectivity predicted lower GCA across groups, and group differences were noted for both variables. Measures of clustering, efficiency, and modularity did not differ across groups or predict GCA. Follow-up analyses investigated three topological types of connectivity—connections among high degree “rich club” nodes, “feeder” connections to these rich club nodes, and “local” connections not involving the rich club. Rich club and local connectivity predicted performance across groups. In a subsample (N=101 controls, 56 patients), a genetic measure reflecting mutation load, based on rare copy number deletions, was associated with longer characteristic path length. Conclusions: Results highlight the importance of characteristic path lengths and rich club connectivity for GCA and provide no evidence for group differences in the relationships between graph metrics and GCA. (JINS, 2016, 22, 240–249)
In Guatemala prior to control initiatives, the main vectors of Trypanosoma cruzi, the causative agent of Chagas disease, were Rhodnius prolixus and Triatoma dimidiata. This study conducted in 2006 in the department of Chiquimula recorded a high level of T. dimidiata infestation and an absence of R. prolixus in all surveyed communities. In Guatemala, the presence of T. dimidiata as domestic, peridomestic and sylvatic populations results in control difficulties as houses are re-infested from the surrounding environment. Entomological surveys, the current method used to select houses in need of control efforts, are labour intensive and time consuming. A time- and cost-effective way to prioritize houses for evaluation and subsequent treatment is the stratification of houses based on the risk of triatomine infestation. In the present study, 17 anthropogenic risk factors were evaluated for associations with house infestation of T. dimidiata including: wall, floor and roof type. There was an increased likelihood of domestic infestation with T. dimidiata associated with the presence of dirt floors (18/29; OR 8.075, 95% CI 2.13–30.6), uncoated bajareque walls (12/17; OR 4.80, 95% CI 1.35–17.1) and triatomine-like faeces on walls (16/26; OR 3.89, 95% CI 1.19–12.7). These factors could be used to target control of T. dimidiata to communities with an increased risk of being infested.
In order to improve the charge/discharge cycling performance of the LiMn2O4 cathode, the spinel LiMn2O4 is coated on the structurally stable SiO2 nanosphere cores, LiMn2O4@SiO2. The core-shell LiMn2O4@SiO2 nanosphere cathodes are prepared by the MnCO3 precipitation on the silica surface and the following solid state reaction of MnCO3@SiO2 with a lithium salt. The charge/discharge cycle stability has improved by the nanostructural characteristics of the LiMn2O4@ shell on the SiO2 core. The cathode composed of LiMn2O4@SiO2 nanospheres exhibits higher capacity retention of 97% than that of LiMn2O4 nanoparticles of 89%, after 100 battery cycles at a 10C rate.
We demonstrate the highly reflective broadband a-Si distributed Bragg reflector fabricated by oblique angle deposition. By tuning the refractive index of a-Si film, the high index contrast material system was achieved. The broadband reflective characteristics of a-Si distributed Bragg reflector were investigated by calculation and fabrication. The broad stop band (Δλ/λ=33.7%, R>99%) with only a five-pair a-Si distributed Bragg reflector was achieved experimentally at center wavelength of 650, 980, and 1550 nm. The size-, feature- and substrate-independent method for highly reflective Bragg reflectors was realized by simple oblique angle evaporation.
Nanoscale superlattice-like (SLL) dielectric was employed to reduce the power consumption of the Phase-change random access memory (PCRAM) cells. In this study, we have simulated and found that the cells with the SLL dielectric have a higher peak temperature compared to that of the cells with the SiO2 dielectric after constant pulse activation, due to the interface scattering mechanism. Scaling of the SLL dielectric has resulted in higher peak temperatures, which can be even higher after material/structural modifications. Furthermore, the SLL dielectric has good material properties that enable the cells to have high endurance. This shows the effectiveness of the SLL dielectric for advanced memory applications.
Enhanced thermal conductivity oxide fuels offer increases in both safety and efficiency of commercial light water reactors. Low-temperature oxidative sintering and Spark Plasma Sintering (SPS) techniques have been used to produce UO2-SiC composite pellets. Oxidative sintering performed for 4 hours at 1200∼1600oC and SPS was employed only for 5 mins at the same temperature. While oxidative sintering failed to achieve enhanced thermal conductivity, the SPS sintered pellet obtained promising features such as higher density, better interfacial contact, and reduced chemical reaction. Thermal conductivity measurement at 100oC, 500oC, and 900oC revealed maximum 62% higher thermal conductivity value, when compared to UO2 pellets, in SPS sintered UO2-10vol% SiC composite pellet. The result shows that the SPS technique is required to sinter UO2-SiC nuclear fuel pellets with a high value of thermal conductivity.
Reflective display technologies aim to enable the delivery of dynamic digital content to devices that have the look and feel of ink on paper. We are presenting herein a novel device architecture design and proprietary electrically addressable inks, which enable low power, disruptive, print-like full color reflective display that can exceed the chromaticity represented by the Specifications for Newsprint Advertising Production (SNAP) standard. We are approaching the challenge of generating bright high-quality reflective color images from the perspective of printing by stacking electro-optic layers of subtractive colorants to address every available color at every location. Using in-plane optical effects, our novel media technology provides fast switching between clear and color states. Thin, flexible electronic media based on this technology has been fabricated by imprinting three-dimensional micro-scale structures with a continuous roll-to-roll (R2R) manufacturing platform. HP’s combination of novel device architecture, proprietary inks, and R2R manufacturing platform enables the required attributes for electronic media such as flexibility, robustness, low power, transparency, print-quality color, and scalability at low cost. The structure property relationship of surfactants has been carried out; their impact on performance of display devices has been studied. These results have been applied to improve the performance of electronic inks. We have demonstrated 3-layer stacked segmented reflective display prototypes, as well as pixelated stacked color reflective display prototypes. The innovations described in this paper are applicable to electronic skins for customizable electronic surfaces and are currently being developed further for electronic paper and signage markets.
All-printed electronics is the key technology to ultra-low-cost, large-area electronics. As a critical step in this direction, we demonstrate that femtosecond laser processing (sintering and ablation) of solution deposited metal nanoparticles enables direct metal patterning at low-temperature with ultra high resolution (∼300nm) to overcome the resolution limitation of the current inkjet direct writing processes.
This could be explained by the combined effects of novel properties of metal nanoparticles such as melting temperature drop, strong absorption of the incident laser beam at surface plasmon mode, lower conductive heat transfer loss, and the relatively weak bonding between nanoparticles. Local thermal control of the laser sintering process could minimize the heat-affected zone and the thermal damage to the substrate and further enhance the resolution of the process. This local nanoparticle deposition and energy coupling enable an environmentally friendly and cost-effective process as well as a low-temperature manufacturing sequence to realize large-area, flexible electronics on polymer substrates.
Trypanosoma cruzi is the protozoan agent of Chagas disease, and the most important parasitic disease in Latin America. Protozoa of the genus Leishmania are global agents of visceral and cutaneous leishmaniasis, fatal and disfiguring diseases. In the 1970s multilocus enzyme electrophoresis demonstrated that T. cruzi is a heterogeneous complex. Six zymodemes were described, corresponding with currently recognized lineages, TcI and TcIIa-e – now defined by multiple genetic markers. Molecular epidemiology has substantially resolved the phylogeography and ecological niches of the T. cruzi lineages. Genetic hybridization has fundamentally influenced T. cruzi evolution and epidemiology of Chagas disease. Genetic exchange of T. cruzi in vitro involves fusion of diploids and genome erosion, producing aneuploid hybrids. Transgenic fluorescent clones are new tools to elucidate molecular genetics and phenotypic variation. We speculate that pericardial sequestration plays a role in pathogenesis. Multilocus sequence typing, microsatellites and, ultimately, comparative genomics are improving understanding of T. cruzi population genetics. Similarly, in Leishmania, genetic groups have been defined, including epidemiologically important hybrids; genetic exchange can occur in the sand fly vector. We describe the profound impact of this parallel research on genetic diversity of T. cruzi and Leishmania, in the context of epidemiology, taxonomy and disease control.
Carrying a functional single nucleotide polymorphism (L503F, c. 1672 C>T) in the gene for the Na-dependent organic cation transporter (OCTN1), increases the risk of Crohn's disease (CD) in some, but not all, populations. Case–control data on New Zealand Caucasians show no differences for CD risk between individuals carrying the L503F OCTN1 C-allele when compared with those carrying the variant T-allele. However, more of the New Zealand CD cases report intolerance to maize and mushrooms than those who report beneficial effects or no differences. The OCTN1 gene encodes a transporter for ergothionine, a fungal metabolite at high levels in mushrooms but not widely common in other dietary items. An inability to tolerate mushrooms showed statistically significant associations with the variant OCTN1 genotype. That is, among those individuals reporting adverse effects from mushrooms, there was a higher frequency of the variant T-allele when compared with the general population, or with CD patients overall. We believe that this is a novel gene–diet association, suggesting that individuals carrying the OCTN1 variant single nucleotide polymorphism may have an enhanced risk of adverse symptoms associated with consuming mushrooms. Nutrigenomic approaches to dietary recommendations may be appropriate in this group.
Previous studies of schizophrenia have suggested a linkage between neuropsychological (NP) deficits and hippocampus abnormality. The relationship between hippocampus volume and NP functioning was investigated in 24 patients with chronic schizophrenia and 24 matched healthy controls. Overall intracranial, white and gray matter, and anterior (AH) and posterior (PH) hippocampus volumes were assessed from magnetic resonance images (MRI). NP domains of IQ, attention, and executive function were also evaluated with respect to volumetric measures. It was hypothesized that AH and PH volumes and episodic memory scores would be positively associated in controls and that the schizophrenia group would depart from this normative pattern. NP functioning was impaired overall and AH volume was smaller in the schizophrenia group. In the controls, the hippocampus–memory relationships involved AH and PH, and correlations were significant for verbal memory measures. In the schizophrenia group, positive correlations were constrained to PH. Negative correlations emerged between AH and verbal and visual memory measures. For both groups, cortical volume negatively correlated with age, but a negative correlation between age and hippocampus volume was found only in the schizophrenia group. In this sample of adults with schizophrenia, atypical relationships between regional hippocampus volumes and episodic memory ability were found, as was an atypical negative association between hippocampus volume and age. (JINS, 2009, 15, 182–195.)
We report the energy band alignment of Ge2Sb2Te5 and a variety of common complementary-metal-oxide-semiconductor (CMOS) compatible materials. These materials include silicon, silicon oxide, hafnium oxide, silicon nitride as well as nickel silicide. High-resolution X-ray photoelectron spectroscopy was employed as the main tool to obtain the core-level spectra, the valence band spectra, and the energy loss spectra. A precise determination of the valence band offsets of Ge2Sb2Te5 and the various materials were obtained. The conduction band offsets were then determined. The energy band line-ups of Ge2Sb2Te5 and these CMOS compatible materials were established.
We report a novel chemical vapor deposition (CVD) process for epitaxial growth of Ge film on GaAs substrate. The resultant layer exhibits device level quality, as shown by high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, high-resolution X-ray diffraction (HRXRD). In addition, atomic force microscopy (AFM) scanning indicates low RMS surface roughness of 5 Å. Secondary ion mass spectrometry (SIMS) reveals negligible out-diffusion of Ga and As into the Ge epilayer. By employing silane passivation, Ge p-MOSFET with TaN/HfO2 gate stack was fabricated on Ge/GaAs heterostructure for the first time, showing excellent output and pinch-off characteristics. A GaAs channel n-MOSFET was also fabricated, using similar SiH4 treatment during gate stack formation. These results reveal a potential solution to integrate Ge p-channel and GaAs n-channel MOSFET for advanced CMOS applications.