Copper-Catalyzed Regioselective Annulation of β-Keto Esters and Propargyl Acetates: Access to Polysubstituted Furans.

A copper-catalyzed regioselective annulation reaction, conducted without ligands or oxidants, has been developed for the preparation of multisubstituted furans from the readily available starting materials, β-keto esters and propargyl acetates. This process accommodates a wide range of functional groups, resulting in furan skeletons with diverse substitution patterns. The method's potential synthetic utility is highlighted by its applicability in gram-scale preparations and late-stage modifications of natural products.

Altering the competitive environment of B cell epitopes significantly extends the duration of antibody production.

Persistent immunoglobulin G (IgG) production (PIP) provides long-term vaccine protection. While variations in the duration of protection have been observed with vaccines prepared from different pathogens, little is known about the factors that determine PIP. Here, we investigated the impact of three parameters on the duration of anti-peptide IgG production, namely amino acid sequences, protein carriers, and immunization programs.

Prevalence, evolution, replication and transmission of H3N8 avian influenza viruses isolated from migratory birds in eastern China from 2017 to 2021.

The continued evolution and emergence of novel influenza viruses in wild and domestic animals poses an increasing public health risk. Two human cases of H3N8 avian influenza virus infection in China in 2022 have caused public concern regarding the risk of transmission between birds and humans. However, the prevalence of H3N8 avian influenza viruses in their natural reservoirs and their biological characteristics are largely unknown.

Research on the Reliability of a Core Control Unit of Highway Electromechanical Equipment Based on Virtual Sensor Data.

The printed circuit board (PCB) is the core control unit of electromechanical equipment. In order to determine the influence of the coupling vibration caused by vehicle-road interaction on the PCB reliability of roadside electromechanical equipment, first, the dynamic load of the vehicle tire is solved by establishing the dynamic model of a vehicle road. Then, the acceleration response data generated by road vibration are obtained by solving the road finite element model.

A quantum dot microspheres-based highly specific and sensitive three-dimensional microarray for multiplexed detection of inflammatory factors.

The development trend ofdiagnostics is to obtain various biological information from a sample at extremely low concentration and volume, which has promoted its progress in accurate and sensitive multiplexed detection. Here, we developed a single color quantum dot (QD) based three-dimensional (3D) structure matrix microarray and conducted the detection of two inflammatory factors (C-reactive protein (CRP) and serum amyloid A (SAA)) by a self-built fluorescence detection system. This strategy increased detection sensitivity by immobilizing the antibody specifically on the 3D substrate because it captured more than about 7 times of 'effective' antibodies compared to the two-dimensional (2D) plane.

Epitope-Containing Short Peptides Capture Distinct IgG Serodynamics That Enable Differentiating Infected from Vaccinated Animals for Live-Attenuated Vaccines.

Differentiating infected from vaccinated animals (DIVA) strategies have been central enabling techniques in several successful viral disease elimination programs. However, owing to their long and uncertain development process, no DIVA-compatible vaccines are available for many important diseases. We report herein a new DIVA strategy based on hybrid protein-peptide microarrays which can theoretically work with any vaccine.

Progressive Temporal-Spatial-Semantic Analysis of Driving Anomaly Detection and Recounting.

For analyzing the traffic anomaly within dashcam videos from the perspective of ego-vehicles, the agent should spatial-temporally localize the abnormal occasion and regions and give a semantically recounting of what happened. Most existing formulations concentrate on the former spatial-temporal aspect and mainly approach this goal by training normal pattern classifiers/regressors/dictionaries with large-scale availably labeled data. However, anomalies are context-related, and it is difficult to distinguish the margin of abnormal and normal clearly.

Genome-wide linear B-cell epitopes of enterovirus 71 in a hand, foot and mouth disease (HFMD) population.

Background: Enteroviruses cause hand, foot and mouth disease (HFMD). The host B-cells recognize the viral proteins and provoke humoral responses. Deciphering the B-cell responses to the viral epitopes helps diagnosis and vaccine development.

Chimeric peptide constructs comprising linear B-cell epitopes: application to the serodiagnosis of infectious diseases.

Linear B-cell epitopes are ideal biomarkers for the serodiagnosis of infectious diseases. However, the long-predicted diagnostic value of epitopes has not been realized. Here, we demonstrated a method, diagnostic epitopes in four steps (DEIFS), that delivers a combination of epitopes for the serodiagnosis of infectious diseases with a high success rate.

Ion-exchange method in the collection of nitrate from freshwater ecosystems for nitrogen and oxygen isotope analysis: a review.

Nitrate (NO3(-)) contamination of freshwater is considered one of the most prevalent global environmental problems. Dual stable isotopic compositions (δ(15)N and δ(18)O) of NO3(-) can provide helpful information and have been well documented as being a powerful tool to track the source of NO3(-) in freshwater ecosystems. The ion-exchange method is a reliable and precise technique for measuring the δ(15)N and δ(18)O of NO3(-) and has been widely employed to collect NO3(-) from freshwater ecosystems.

Interaction between abscisic acid and nitric oxide in PB90-induced catharanthine biosynthesis of catharanthus roseus cell suspension cultures.

Elicitations are considered to be an important strategy to improve production of secondary metabolites of plant cell cultures. However, mechanisms responsible for the elicitor-induced production of secondary metabolites of plant cells have not yet been fully elucidated. Here, we report that treatment of Catharanthus roseus cell suspension cultures with PB90, a protein elicitor from Phytophthora boehmeriae, induced rapid increases of abscisic acid (ABA) and nitric oxide (NO), subsequently followed by the enhancement of catharanthine production and up-regulation of Str and Tdc, two important genes in catharanthine biosynthesis.

Integrated poly(dimethysiloxane) with an intrinsic nonfouling property approaching "absolute" zero background in immunoassays.

The key to achieve a highly sensitive and specific protein microarray assay is to prevent nonspecific protein adsorption to an "absolute" zero level because any signal amplification method will simultaneously amplify signal and noise. Here, we develop a novel solid supporting material, namely, polymer coated initiator integrated poly(dimethysiloxane) (iPDMS), which was able to achieve such "absolute" zero (i.e.

[Comparison between therapeutic effects of acupuncture and intravenous injection of amiodarone in the treatment of paroxymal atrial fibrillation and atrial flutter].

Objective: To probe the feasibility of acupuncture in conversion of paroxymal atrial fibrillation and atrial flutter.

Methods: Eighty cases of atrial fibrillation and atrial flutter were randomly divided into 2 groups, a treatment group and a control group, 40 cases in each group. The treatment group were treated with acupuncture at Neiguan (PC 6), Shenmen (HT 7), Danzhong (CV 17) and others, and the control group with intravenous injection of amiodarone.