Rapid and sensitive insulated isothermal PCR for point-of-need feline leukaemia virus detection

Objectives: Feline leukaemia virus (FeLV), a gamma retrovirus, causes diseases of the feline haematopoietic system that are invariably fatal. Rapid and accurate testing at the point-of-need (PON) supports prevention of virus spread and management of clinical disease. This study evaluated the performance of an insulated isothermal PCR (iiPCR) that detects proviral DNA, and a reverse transcription (RT)-iiPCR that detects both viral RNA and proviral DNA, for FeLV detection at the PON. Methods: Mycoplasma haemofelis, feline coronavirus, feline herpesvirus, feline calicivirus and feline immunodeficiency virus were used to test analytical specificity. In vitro transcribed RNA, artificial plasmid, FeLV strain American Type Culture Collection VR-719 and a clinical FeLV isolate were used in the analytical sensitivity assays. A retrospective study including 116 clinical plasma and serum samples that had been tested with virus isolation, real-time PCR and ELISA, and a prospective study including 150 clinical plasma and serum samples were implemented to evaluate the clinical performances of the iiPCR-based methods for FeLV detection. Results: Ninety-five percent assay limit of detection was calculated to be 16 RNA and five DNA copies for the RT-iiPCR, and six DNA copies for the iiPCR. Both reactions had analytical sensitivity comparable to a reference real-time PCR (qPCR) and did not detect five non-target feline pathogens. The clinical performance of the RT-iiPCR and iiPCR had 98.82% agreement (kappa[κ] = 0.97) and 100% agreement (κ = 1.0), respectively, with the qPCR (n = 85). The agreement between an automatic nucleic extraction/RT-iiPCR system and virus isolation to detect FeLV in plasma or serum was 95.69% (κ = 0.95) and 98.67% (κ = 0.85) in a retrospective (n = 116) and a prospective (n = 150) study, respectively. Conclusions and relevance: These results suggested that both RT-iiPCR and iiPCR assays can serve as reliable tools for PON FeLV detection

Longitudinal changes in prospective memory and their clinical correlates at 1-year follow-up in first-episode schizophrenia

This study aimed to investigate prospective memory (PM) and the association with clinical factors at 1-year follow-up in first-episode schizophrenia (FES). Thirty-two FES patients recruited from a university-affiliated psychiatric hospital in Beijing and 17 healthy community controls (HCs) were included. Time- and event-based PM (TBPM and EBPM) performances were measured with the Chinese version of the Cambridge Prospective Memory Test (CCAMPROMPT) at baseline and at one-year follow-up. A number of other neurocognitive tests were also administered. Remission was determined at the endpoint according to the PANSS score _ 3 for selected items. Repeated measures analysis of variance revealed a significant interaction between time (baseline vs. endpoint) and group (FES vs. HCs) for EBPM (F(1, 44) = 8.8, p = 0.005) and for all neurocognitive components. Paired samples ttests showed significant improvement in EBPM in FES (13.1±3.7 vs. 10.3±4.8; t = 3.065, p = 0.004), compared to HCs (15.7±3.6 vs. 16.5±2.3; t = -1.248, p = 0.230). A remission rate of 59.4% was found in the FES group. Analysis of covariance revealed that remitters performed significantly better on EBPM (14.9±2.6 vs. 10.4±3.6; F(1, 25) = 12.2, p = 0.002) than non-remitters at study endpoint. The association between EBPM and 12-month clinical improvement in FES suggests that EBPM may be a potential neurocognitive marker for the effectiveness of standard pharmacotherapy. Furthermore, the findings also imply that PM may not be strictly a trait-related endophenotype as indicated in previous studies

New Family of Robust 2D Topological Insulators in van der Waals Heterostructures

We predict a new family of robust two-dimensional (2D) topological insulators in van der Waals heterostructures comprising graphene and chalcogenides BiTeX (X=Cl, Br and I). The layered structures of both constituent materials produce a naturally smooth interface that is conducive to proximity induced new topological states. First principles calculations reveal intrinsic topologically nontrivial bulk energy gaps as large as 70-80 meV, which can be further enhanced up to 120 meV by compression. The strong spin-orbit coupling in BiTeX has a significant influence on the graphene Dirac states, resulting in the topologically nontrivial band structure, which is confirmed by calculated nontrivial Z2 index and an explicit demonstration of metallic edge states. Such heterostructures offer an unique Dirac transport system that combines the 2D Dirac states from graphene and 1D Dirac edge states from the topological insulator, and it offers new ideas for innovative device designs

Electrodeposition of Gold Alloys and the Mechanical Properties

Strengthening of electrodeposited gold-based materials is achieved by alloying with copper according to the solid solution strengthening mechanism. Composition of the Au–Cu alloys is affected by the applied current density. The mechanical properties are evaluated by micro-compression tests to evaluate the mechanical properties in microscale to take consideration of the sample size effect for applications as microcomponents in MEMS devices. The yield strength reaches 1.15 GPa for the micropillar fabricated from constant current electrodeposited Au–Cu film, and the film is composed of 30.3 at% Cu with an average grain size of 5.3 nm. The yield strength further increases to 1.50 GPa when pulse current electrodeposition method is applied, and the Cu concentration is 36.9 at% with the average grain size at 4.4 nm

Numerical ability and improvement through interindividual cooperation varied between two cyprinid fish species, qingbo and crucian carp

We used qingbo (Spinibarbus sinensis) and Chinese crucian carp (Carassius auratus) to test whether numerical discrimination could be improved by the coexistence and possible cooperation of conspecies or heterospecies. We conducted a spontaneous shoal choice test of singletons, conspecific dyads and heterospecific dyads under different numerical comparisons (8 vs. 12, 9 vs. 12 and 10 vs. 12). Singletons of qingbo could discriminate only 8 vs. 12, whereas the dyads of qingbo showed better numerical acuity, as they could discriminate 10 vs. 12. Crucian carp may have poor numerical ability, as both singleton and dyads showed no significant preference for larger stimulus shoals, even at the ‘easier’ numerical discrimination, that is, 8 vs. 12. Furthermore, heterospecific dyads of crucian carp and qingbo did not show significant preference for larger shoals at any numerical comparison in the present study. It is suggested that both the numerical ability and the possibility for improvement by interindividual interaction and hence cooperation might vary among fish species, and the interaction between heterospecies in the present study showed negative effect on numerical ability possibly due to the different behavioural and cognitive traits which make the information transfer and consensus difficult to reach

Pulse-Current Electrodeposition of Gold

Pulse-current electrodeposition and a sulfite-based electrolyte were used in fabrication of pure gold films. Surface of the pulse-electrodeposited gold film possessed less defect, lower roughness, smaller grain size, and denser texture when compared with the gold film prepared by constant-current electrodeposition. Microstructures and compressive yield strength of the electrodeposited gold could be controlled by regulating the pulse on-time and off-time intervals in pulse-current electrodeposition. The gold film prepared under the optimum conditions showed an average grain size at 10.4 nm, and the compressive yield strength reached 800 MPa for a pillar-type micro-specimen having dimensions of 10 μm × 10 μm × 20 μm fabricated from the pulse-electrodeposited gold film. Average grain size of the pulse-electrodeposited gold film was much smaller, and the compressive yield strength was much higher than the values reported in other studies. The high strength is due to the grain boundary strengthening mechanism known as the Hall-Petch relationship. In general, the pulse-electrodeposited gold films showed yield strength ranging from 400 to 673 MPa when the average grain size varied by adjusting the pulse-electrodeposition parameters

Synergy of Pd atoms and oxygen vacancies on In₂O₃ for methane conversion under visible light

Methane (CH4) oxidation to high value chemicals under mild conditions through photocatalysis is a sustainable and appealing pathway, nevertheless confronting the critical issues regarding both conversion and selectivity. Herein, under visible irradiation (420 nm), the synergy of palladium (Pd) atom cocatalyst and oxygen vacancies (OVs) on In2O3 nanorods enables superior photocatalytic CH4 activation by O2. The optimized catalyst reaches ca. 100 μmol h-1 of C1 oxygenates, with a selectivity of primary products (CH3OH and CH3OOH) up to 82.5%. Mechanism investigation elucidates that such superior photocatalysis is induced by the dedicated function of Pd single atoms and oxygen vacancies on boosting hole and electron transfer, respectively. O2 is proven to be the only oxygen source for CH3OH production, while H2O acts as the promoter for efficient CH4 activation through ·OH production and facilitates product desorption as indicated by DFT modeling. This work thus provides new understandings on simultaneous regulation of both activity and selectivity by the synergy of single atom cocatalysts and oxygen vacancies

4,4′-[4,4′-Sulfonyl­bis­(p-phenyl­ene­oxy)]dibutanoic acid

In the title compound, C20H22O8S, the dihedral angle between the two benzene rings is 81.6 (3)°. The benzene-connected portions of the alk­oxy substituents are almost coplanar with their respective rings [C—C—O—C torsion angles of 174.77 (17) and −178.5 (4)°]. One of the butanoic acid groups is disordered over two conformations with a site-occupancy ratio 0.719 (6):0.281 (6). In the crystal, pairs of O—H⋯O hydrogen bonds link the mol­ecules into infinite zigzag chains along [130]