Electro- and photon-induced cooling in BNT-BT-SBET relaxors with in situ optical temperature sensing

A novel lead-free luminescent ferroelectric (FE) ceramic, Bi0.5Na0.5TiO3-0.06BaTiO3-0.055Sr0.7Bi0.18Er0.02□0.1TiO3, is developed with an adiabatic temperature change (ΔT) of 0.7 K under an electric-field (E) of 60 kV/cm at room temperature (RT), an anti-stokes fluorescence (FL) cooling and a maximum optical T sensitivity of 0.0055 K-1 at 522 K. Interestingly, the electrocaloric (EC) response reaches a saturation at permittivity-shoulder T of 100 oC, meanwhile the maximized emission intensity of 2H11/2→4I15/2 occurs. T- and E-tunable enhancement of 2H11/2→4I15/2 emission intensity is due to the population inversion from the 4S3/2 to 2H11/2 states caused by an incoherent regime consisting of FE phase and polar nanoregions (PNRs) in a relaxor (R) matrix

Detection of Staphylococcus aureus virulence gene pvl based on CRISPR strip

IntroductionStaphylococcus aureus (S. aureus) is a prominent pathogen responsible for both hospital-acquired and community-acquired infections. Among its arsenal of virulence factors, Panton-Valentine Leucocidin (PVL) is closely associated with severe diseases such as profound skin infections and necrotizing pneumonia. Patients infected with pvl-positive S. aureus often exhibit more severe symptoms and carry a substantially higher mortality risk. Therefore, it is crucial to promptly and accurately detect pvl-positive S. aureus before initiating protective measures and providing effective antibacterial treatment.MethodsIn this study, we propose a precise identification and highly sensitive detection method for pvl-positive S. aureus based on recombinase-assisted amplification and the CRISPR-ERASE strip which we previously developed.ResultsThe results revealed that this method achieved a detection limit of 1 copy/μL for pvl-positive plasmids within 1 hour. The method successfully identified all 25 pvl-positive and 51 pvl-negative strains among the tested 76 isolated S. aureus samples, demonstrating its concordance with qPCR.DiscussionThese results show that the CRISPR-ERASE detection method for pvl-positive S. aureus has the advantages of high sensitivity and specificity, this method combines the characteristics of recombinase-assisted amplification at room temperature and the advantages of ERASE test strip visualization, which can greatly reduce the dependence on professional laboratories. It is more suitable for on-site detection than PCR and qPCR, thereby providing important value for rapid on-site detection of pvl

Shared and differing functional connectivity abnormalities of the default mode network in mild cognitive impairment and Alzheimer's disease.

Alzheimer's disease (AD) and mild cognitive impairment (MCI) both show abnormal resting-state functional connectivity (rsFC) of default mode network (DMN), but it is unclear to what extent these abnormalities are shared. Therefore, we performed a comprehensive meta-analysis, including 31 MCI studies and 20 AD studies. MCI patients, compared to controls, showed decreased within-DMN rsFC in bilateral medial prefrontal cortex/anterior cingulate cortex (mPFC/ACC), precuneus/posterior cingulate cortex (PCC), right temporal lobes, and left angular gyrus and increased rsFC between DMN and left inferior temporal gyrus. AD patients, compared to controls, showed decreased rsFC within DMN in bilateral mPFC/ACC and precuneus/PCC and between DMN and left inferior occipital gyrus and increased rsFC between DMN and right dorsolateral prefrontal cortex. Conjunction analysis showed shared decreased rsFC in mPFC/ACC and precuneus/PCC. Compared to MCI, AD had decreased rsFC in left precuneus/PCC and between DMN and left inferior occipital gyrus and increased rsFC in right temporal lobes. MCI and AD share a decreased within-DMN rsFC likely underpinning episodic memory deficits and neuropsychiatric symptoms, but differ in DMN rsFC alterations likely related to impairments in other cognitive domains such as language, vision, and execution. This may throw light on neuropathological mechanisms in these two stages of dementia

Simulation study of BESIII with stitched CMOS pixel detector using ACTS

Reconstruction of tracks of charged particles with high precision is very crucial for HEP experiments to achieve their physics goals. As the tracking detector of BESIII experiment, the BESIII drift chamber has suffered from aging effects resulting in degraded tracking performance after operation for about 15 years. To preserve and enhance the tracking performance of BESIII, one of the proposals is to add one layer of thin CMOS pixel sensor in cylindrical shape based on the state-of-the-art stitching technology, between the beam pipe and the drift chamber. The improvement of tracking performance of BESIII with such an additional pixel detector compared to that with only the existing drift chamber is studied using the modern common tracking software ACTS, which provides a set of detector-agnostic and highly performant tracking algorithms that have demonstrated promising performance for a few high energy physics and nuclear physics experiments

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Methylprednisolone as Adjunct to Endovascular Thrombectomy for Large-Vessel Occlusion Stroke

Importance It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy. Objective To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO. Design, Setting, and Participants This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023.InterventionsEligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy. Main Outcomes and Measures The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours. Results Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo. Conclusions and Relevance Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability.Trial RegistrationChiCTR.org.cn Identifier: ChiCTR210005172

Design of chemically treated activated carbon fibers for mercury removal and advanced membranes for water purification

There are mainly two projects in this thesis, one is to develop chemically treated activated carbon fibers for mercury removal from power plant effluents, and the other one is to design advanced nanofiltration membranes for water purification with specific features, i.e. solvent resistance and antifouling properties. The current technologies for mercury removal involve the use of chemically treated activated carbon powder has had limited success. These systems present practical problems in dealing with the large amount of absorbents required to insure quantitative removal of the Hg. The system we developed depends on using a chemically treated high surface area activated carbon fibers (50~600 m2/g), which provides very effective contact efficiency with the power plant effluent. For chemical modifications of activated carbon fibers, sulfur and bromine containing groups were introduced into the carbon matrix. Generally, sulfur impregnations decrease surface area and pore volume but increase the Hg uptake capacities when compared to untreated activated carbon fibers. For our sulfur-treated samples, sulfur atoms were incorporated into the carbon matrix in the form of sulfide and sulfate. The sulfide groups appeared to be more effective for mercury removal than sulfate, which was probably because the lone pairs of sulfide groups could act as the interaction site for Hg adsorption, or at least the initial point of attachment. Three approaches were explored for bromination; namely, 1) bromination using Br2 vapor, 2) bromine deposition by an electrochemical reaction and 3) impregnation of bromine using KBr solution. Both static and dynamic tests were carried out to measure the mercury adsorption performances of these brominated samples. For the brominated samples treated by Br2 vapor and electrochemical method, they showed stable mercury adsorption performance (30% to 33% removal) up to 3 months, which showed great potential promising for commercialization. A possible mechanism for mercury adsorption, which was likely to involve the formation of oxidized mercury complexes (e.g. [HgBr]+, [HgBr2] and [HgBr4]2-), was also discussed. Besides the chemical structures, pore properties also play an important role on mercury adsorption performance at room temperature. Usually, micropores are mainly responsible for mercury adsorption while mesopores may serve as transportation channels. However, physical adsorption capability decreases due to desorption at high temperatures. Nanofiltration membranes can be used to separate salts and small molecules from the solution by applying a pressure. By far the most processes is dealing with aqueous solutions, however, with the emerging of membranes usage in food applications, petrochemical applications and pharmaceutical areas, the membranes suited for applications in organic media are required. To address this problem, the crosslinking of polyimide membranes is a commonly known method to prepare membranes suitable for solvent resistant nanofiltration. In this work, preparation of crosslinked membranes of P84 copolyimide asymmetric membranes using branched polyethylenimine (PEI) at different reaction temperatures was studied. The rejection sequence of CaCl2 > NaCl > Na2SO4 indicated a positively charged membrane surface. Additionally, the resultant membranes were very stable in dimethyl formamide (DMF), a harsh aprotic solvent. Even after soaking in DMF for 1 month, there were no significant changes in membrane performance or membrane structure. Fouling caused by organic impurities such as proteins, humic substances and polysaccharides is another concern for membrane processes. Polyelectrolyte multilayer (PEM) films consisting of sulfonated poly (ether ether ketone) sPEEK alternating with selected anionic layers were developed for fouling resistant properties. Two novel variables were introduced in our approach, a) the use of pressure and b) organic solvents, during the alternating physisorption of oppositely charged polyelectrolytes on porous supports through the electrostatic self-assembly. It was shown that the use of pressure and/or organic solvent systems could increase the salt rejection of the PEMs by several times while still remaining a high water flux. The PEMs also had a better antifouling property in comparison with NTR 7450, a commercial NF membrane with a sulfonated surface

A survey of Pholcus spiders (Araneae, Pholcidae) from the Qinling Mountains of central China, with descriptions of seven new species

We report 18 spider species of the genus Pholcus Walckenaer, 1805 from a survey in the Qinling Mountains of central China. They belong to four species groups and include seven species new to science: Pholcus jiaozuo Yang & Yao, sp. nov. (♂♀) in the taishan species group; P. luonan Yang & Yao, sp. nov. (♂♀), P. luoyang Yang & Yao, sp. nov. (♂♀), P. lushan Yang & Yao, sp. nov. (♂♀), P. shangluo Yang & Yao, sp. nov. (♂♀), P. weinan Yang & Yao, sp. nov. (♂♀) and P. yuncheng Yang & Yao, sp. nov. (♂♀) in the yichengicus species group. Detailed diagnoses, descriptions, photomicroscopy images and DNA barcodes of all new species are provided. Our study will make a significant contribution to understanding species diversity and zoogeography of the region

Complete chloroplast genome sequence of tropical orchid Renanthera imschootiana

Renanthera imschootiana Rolfe is an epiphyte of genus Renanthera in family Orchidaceae. R. imschootiana is a rare tropical orchid with high ornamental value. We determined its complete chloroplast genome sequence to better understand its relationship with other Orchidaceae species. The chloroplast genome of R. imschootiana has a length of 143,836 bp, which comprises a large single copy region of 83,356 bp, a small single copy region of 11,172 bp, and a pair of reverse repeat regions of 24,654 bp each. Its genome has a total GC content of 36.8% and contains 127 genes, including 82 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Maximum likelihood phylogenetic analysis showed that R. imschootiana is closely related to Vanda brunnea, Holcoglossum flavescens, and H. amesianum

The complete chloroplast genome sequence of Illigera celebica

Illigera celebica is an evergreen woody vine that belongs to genus Illigera Bl in the family Hernandiaceae and has medicinal value. The complete chloroplast genome of I. celebica was sequenced to determine its phylogenetic location with respect to the other species under the Laurales. Its whole chloroplast genome is 156,123 bp in length, and comprises a large single-copy region (LSC, 84,913 bp), a small single-copy region (SSC,18,775 bp), and a pair of inverted repeats (IRs, 26,217 bp). The overall GC content is 39.2% (LSC, 37.8%; SSC, 33.9%; IR, 43.4%). Maximum likelihood phylogenetic analysise (TVM + F + R2 model) was conducted using 15 complete chloroplast genomes of Laurales, and the results confirmed that Hernandia nymphaeifolia and Wilkiea huegeliana were located in the same lineage