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Introduction RESLES (Reversible splenial lesion syndrome) can be observed secondary to various diseases, and intramyelinic edema may play a crucial role in the pathogenesis of SCC (Splenium of the corpus callosum). Some studies have suggested that hypoxic-ischaemic encephalopathy may constitute a risk factor for SCC lesions. However, the potential impact of high-altitude environments on SCC, especially during chronic exposure, remain obscure.Methods Our study included 19 patients who satisfied the diagnostic criteria of RESLES at high altitudes. Ten low-altitude patients with RESLES were included as controls. All participants received MRI (Magnetic resonance imaging) scans twice. Routine blood tests, liver, kidney and thyroid function, coagulation function, electrolytes and vitamins were detected during hospitalization and before discharge. In addition, the patients were followed up in May 2023.Results Hypoxic environments at high altitudes may increase the risk of RESLES. The two groups showed different clinical symptoms. High-altitude patients had significantly higher CRP levels than low-altitude patients. The lesion size in high-altitude patients showed a positive correlation with SaO2 levels. However, the patients at low altitudes had positive correlation trends between lesion size and several inflammatory markers (WBC, NEU and CRP). All patients had a benign prognosis that may not be affected by the use of prednisone acetate.Conclusions Hypoxic environments at high altitudes may play a role in the aetiology of RESLES. Additionally, RESLES is a reversible disease and the administration of glucocorticoids may be dispensable for its treatment.

Soil bulk density is a basic but important physic soil property related to soil porosity, soil moisture and hydraulic conductivity, which is crucial to soil quality assessment and land use management. In this study, we evaluated the spatial variability of soil bulk density in the 0–20, 20–40, 40–60 and 60–100 cm layers as well as its affecting factors in Southwest China's agricultural intensive area. Results indicated the mean value of surface soil bulk density (0–20 cm) was 1.26 g cm−3, significantly lower than that of subsoil (20–100 cm). No statistical difference existed among the subsoil with a mean soil bulk density of 1.54 g cm−3. Spatially, soil bulk density played a similar spatial pattern in soil profile, whereas obvious differences were found in details. The nugget effects for soil bulk density in the 0–20 and 20–40 cm layers were 27.22 and 27.02% while 12.06 and 3.46% in the 40–60 and 60–100 cm layers, respectively, gradually decreasing in the soil profile, indicating that the spatial variability of soil bulk density above 40 cm was affected by structural and random factors while dominated by structural factors under 40 cm. Soil organic matter was the controlling factor on the spatial variability of soil bulk density in each layer. Land use and elevation were another two dominated factor controlling the spatial variability of soil bulk density in the 0–20 and 40–60 cm layers, respectively. Soil genus was one of the dominated factors controlling the spatial variability of soil bulk below 40 cm.

The role of the hippocampus in delay eyeblink conditioning (DEC) remains controversial. Here, we investigated the involvement of the hippocampus in DEC with a soft tone as the conditioned stimulus (CS) by using electrolytic lesions or muscimol inactivation of guinea pig dorsal hippocampus. Interestingly, when a soft tone was used as a CS, electrolytic lesions of the hippocampus significantly retarded acquisition of the conditioned response (CR), and muscimol infusions into hippocampus distinctly inhibited the acquisition and expression of CR, but had no significant effect on consolidation of well-learned CR. In contrast, both electrolytic lesions and muscimol inactivation of hippocampus produced no significant deficits in the CR when a loud tone was used as the CS. These results demonstrate that the hippocampus is essential for the DEC when the delay task was rendered more difficult.

Abstract Background Contact tracing has been essential to reducing spread of COVID-19. Singapore leveraged technology to assist with contact tracing efforts using a Bluetooth-based app and token platform called ‘TraceTogether’. Methods We reviewed the impact of this system during the country’s Delta and Omicron waves (24 August 2021 to 17 February 2022) to identify differences in number of close contacts and time savings between full automation using TraceTogether alone as compared to manual contact tracing supplemented by TraceTogether. Characteristics of digital contact tracing app or token users were reviewed. Thereafter, the number of close contacts identified by manual and digital contact tracing methods, and the number of confirmed COVID-19 cases among contacts were analysed. The difference in time taken for identification of close contacts was also determined. Findings Adoption rate for TraceTogether was high, with 93.3% of cases having a registered device. There was a 9.8 h (34.9%) reduction in time savings for close contacts to be informed using TraceTogether alone compared to manual contact tracing supplemented by TraceTogether. The proportion of close contacts automatically identified through TraceTogether alone and turned positive was 3.6%. For those identified through manual contact tracing supplemented by TraceTogether, this proportion was 12.5% and 6.2% for those served quarantine orders and health risk warnings respectively. Interpretation The high adoption rate of ‘TraceTogether’ suggest that digital solutions remain a promising option to improve contact tracing in future epidemics. This may have been through its concurrent use with vaccine differentiated public health measures and policies which engender public trust. There is future potential for utilising such technology in managing communicable diseases to achieve good public health outcomes.

Lens focused proton radiograph on thin objects is demonstrated using an 11-MeV proton cyclotron at China Academy of Engineering Physics. The proton beam exiting from the tested objects is focused onto the image plane by a magnetic lens system mitigating image blur caused by multiple Coulomb scattering. Both simulations and experiments show that clear images can be obtained with a lens system for the objects with thickness up to 2.7 × 10-2 g/cm2 and the error for the areal density measurement is measured to be less than 2.3%. For the objects with thickness between 2.7 × 10-3 g/cm2 and 2.7 × 10-2 g/cm2, 100-200 μm of spatial resolution is achieved. [ABSTRACT FROM AUTHOR]

Background: Escherichia coli does not produce n-butanol naturally, but can be butanologenic when related enzymes were expressed using inducible elements on plasmids. In this study we attempted to confer E. coli strain capability of automatic excretion of the chemical by employing a native anaerobic promoter. Also, a novel DNA kit was designed for PCR preparation of linear DNA fragments to perform strain modification. The kit is primarily composed of two mother vectors, co-transformation of linear DNAs into E. coli can simultaneously introduce two butanol synthetic operons into the chromosome and create two in-frame gene deletions at targeted native loci. Results: E. coli strain Bw2V carries plasmid pCNA-PHC and pENA-TA, both utilizes native anaerobic promoter Phya for the expression of butanol synthetic enzymes. When Bw2V was subjected in anaerobic fermentation using medium containing extra glucose, the accumulated n-butanol in the broth was up to 2.8 g/L in bioreactor; as the genetic element expressing the same pathway was introduced into the genome, the titer of butanol was 1.4 g/L. Conclusions: The expression systemusing Phya is effective in applications that involve expression plasmids as also applicable in ectopic expression as single copy on the chromosome. Results imply that Phya can be subjected for broader application in bioproduction of more feedstock chemicals. [ABSTRACT FROM AUTHOR]

Via structural searching methodology and first-principles calculations, we predicted two new BC6N allotropes, a C-centered monoclinic BC6N (Cm-BC6N) and a primitive-centered monoclinic BC6N (Pm-BC6N). The lattice vibrations, elastic properties, ideal strength, theoretical hardness, and electronic structure of the predicted BC6N were investigated systematically. Our results reveal that Cm-BC6N is more favorable energetically than graphite-like g-BC6N above 20.6 GPa, which is lower than the transition pressures of r-BC6N, t-BC6N, and Pm-BC6N. Both Cm-BC6N and Pm-BC6N are indirect semiconductors with band gaps of 2.66 eV and 0.36 eV, respectively. Cm-BC6N exhibits the excellent ideal shear strength of 53.9 GPa in (011)[01 ], much greater than that of Pm-BC6N (25.0 GPa in (010)[101] shear direction), and Cm-BC6N shows a much lower anisotropy in shear strength than Pm-BC6N. The Vickers hardness of Cm-BC6N is estimated to be above 80 GPa, which is more outstanding than those of t-BC6N and r-BC6N. [ABSTRACT FROM AUTHOR]