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As the main biological components of the air ecosystem, airborne microorganisms play an important role in ecosystem function, and most existing studies focus on their health and environmental effects, while ignoring ecological effects. In this study, air microbial samples from two sampling points in the coastal city of Qingdao were collected by a large volume air sampler. The Illumina MiSeq and PacBio high-throughput sequencing methods were used to analyze the microbial community structure and diversity of the two sampling points. The results showed that there were significant differences in the number and relative abundances of microorganisms identified by the two platforms, and with the refinement of the sample classification, the differences in the community became increasingly significant. Proteobacteria and Firmicutes were the dominant bacterial phyla among the airborne microorganisms. MiSeq sequencing showed that the relative abundances of unidentified bacteria were as high as 8.03–16.42% in MiSeq sequencing, while they were almost undetected in PacBio sequencing. Based on the different sequencing platforms, Bacilli, Gammaproteobacteria and Alphaproteobacteria could be seen as significant gaps in the two sampling points. Betaproteobacteria showed differences only in the coastal area, while the other 14 classes were differentially abundant in the urban area. Pseudomonas was the main genus in the aerosol, followed by Lactococcus. The relative abundances of bacterial taxa displayed statistically significant differences in the different functional areas. There were more diverse microbes in the urban area than in the coastal area; moreover, the relative abundances of dominant genera showed significant differences, such as Variovorax and Deinococcus.

Human insulin (INS) gene diverged from the ancestral genes of invertebrate and mammalian species millions of years ago. We previously found that mouse insulin gene (Ins2) isoforms are expressed in brain choroid plexus (ChP) epithelium cells where insulin secretion is regulated by serotonin and not by glucose. We further compared human INS isoform expression in postmortem ChP and islets of Langerhans. We uncovered novel INS upstream open reading frame (uORF) isoforms and their protein products. In addition, we found a novel alternatively spliced isoform that translates to a 74-amino acid (AA) proinsulin containing a shorter 19-AA C-peptide sequence, herein designated Ca-peptide. The middle portion of the conventional C-peptide contains b-sheet (GQVEL) and hairpin (GGGPG) motifs that are not present in Ca-peptide. Islet amyloid polypeptide (IAPP) is not expressed in ChP and its amyloid formation was inhibited in vitro by Ca-peptide more efficiently than by C-peptide. Of clinical relevance, the ratio of the 74-AA proinsulin to proconvertase processed Ca-peptide was significantly increased in islets from type 2 diabetes mellitus (T2DM) autopsy donors. Intriguingly, 100 years after the discovery of insulin we found that INS isoforms are present in ChP from insulin-deficient autopsy donors.

In recent years, a series of manifestations of American political divide have aroused widespread concern in the international community. Tracing the source and analyzing the extent of American political divide are important issues, closely related to the security and stability of the international community. As an important part of American political system, the performance of American civil-military relations shows the state of American political system in a concentrated manner. Based on historical reviews and current comments of American civil-military relations, it can be concluded that although American politics has shown divisions, American political system is relatively stable.

In this paper, a control scheme of four - rotor UAV is designed. Firstly, the control model of uav is built in Simulink. Then, the dynamics model of uav is carried out, and the control scheme of UAV is deduced theoretically. Finally, the control model is simulated to verify the feasibility of the design scheme. After simulation tuning, Simmechanics and Simulink are combined to carry out 3d UAV model simulation. The effectiveness of the designed control scheme is proved by the visual movement of the 3d model of the four-rotor UAV, and the designed control scheme can be applied to the UAV.

Thermopile infrared detector is one of the earliest infrared detectors. In order to solve the problem of inefficient surface area and poor performance of traditional four-ended beam thermopile devices, a small and high-performance single-ended beam thermopile infrared detector was designed. Firstly, the working principle of the detector is introduced. Secondly, the structure of the detector is introduced. Silicon nitride is selected as the absorbing layer material, and P/N polycrystalline silicon is selected as the thermocouple material. And through theoretical calculation, compared with the four-end beam thermopower infrared detector, the detector has small size, high detection rate and high response rate. Finally, the correctness of the theory is verified by ANSYS software simulation, and the technological process of the detector is given.

The choroid plexus (ChP) is a highly vascularized tissue found in the brain ventricles, with an apical epithelial cell layer surrounding fenestrated capillaries. It is responsible for the production of most of the cerebrospinal fluid (CSF) in the ventricular system, subarachnoid space, and central canal of the spinal cord, while also constituting the blood-CSF barrier (BCSFB). In addition, epithelial cells of the ChP (EChP) synthesize neurotrophic factors and other signaling molecules that are released into the CSF. Here, we show that insulin is produced in EChP of mice and humans, and its expression and release are regulated by serotonin. Insulin mRNA and immune-reactive protein, including C-peptide, are present in EChP, as detected by several experimental approaches, and appear in much higher levels than any other brain region. Moreover, insulin is produced in primary cultured mouse EChP, and its release, albeit Ca(2+) sensitive, is not regulated by glucose. Instead, activation of the 5HT2C receptor by serotonin treatment led to activation of IP3-sensitive channels and Ca(2+) mobilization from intracellular storage, leading to insulin secretion. In vivo depletion of brain serotonin in the dorsal raphe nucleus negatively affected insulin expression in the ChP, suggesting an endogenous modulation of ChP insulin by serotonin. Here, we show for the first time to our knowledge that insulin is produced by EChP in the brain, and its release is modulated at least by serotonin but not glucose.

Liquid nitrogen has been working as an important medium in fire extinguishing and prevention, due to its efficiency in oxygen exclusion and heat removal. Such a technique is especially crucial for coal industry in China. We built a tunnel model with a temperature monitor system (with 36 thermocouples installed) to experimentally study heat and mass transfer of liquid nitrogen in non-homogeneous coal porous media (CPM), and expected to optimize parameters of liquid nitrogen injection in engineering applications. Results indicate that injection location and amount of liquid nitrogen, together with air leakage, significantly affect temperature distribution in CPM, and non-equilibrium heat inside and outside of coal particles. The injection position of liquid nitrogen determines locations of the lowest CPM temperature and liquid nitrogen residual. In the deeper coal bed, coal particles take longer time to reach thermal equilibrium between their surface and inside. Air leakage accelerates temperature increase at the bottom of the coal bed, which is a major reason leading to fire prevention inefficiency. Measurement fluctuation of CPM temperature may be caused by incomplete contact of coal particles with liquid nitrogen flowing in the coal bed. Moreover, the secondary temperature drop (STD) happens and grows with the more injection of liquid nitrogen, and the STD phenomenon is explained through temperature distributions at different locations.

Long non-coding RNAs (LncRNAs) have been found to play important roles in maintaining and promoting cellular proliferation in cancerous cells. One such lncRNA, LINC00963 has been found to promote cellular proliferation, migration and tumorigenesis in prostate, ovarian, breast and non-small cell lung (NSCLC) cancer. In this study, we aim to identify important functional regions of this lncRNA with a view to identify unique regions for targeted drug therapy. In order to achieve this, we sought to investigate this lncRNA in the A549 NSCLC cell line. We found that LINC00963 was highly expressed and when targeted with either siRNAs or antisense oligonucleotides, cells rapidly undergo apoptosis. Using cell death as a proxy for loss-of-function, we characterized LINC00963 at the genomic level using a CRIPSRScan approach. CRISPRScan is a novel way of determining lncRNA functional domains through the introduction of local mutations. These mutations could potentially disrupt lncRNA function, which for LINC00963 would lead to apoptosis of the cell. We created a unique lentivirus library comprised of 1784 single guide RNAs spanning the length of LINC00963 in order to precisely identify regions of functional importance. Upon transduction in a stably expressing Cas9-A549 cell line, we collected cellular fractions over time, and using high-throughput sequencing (NextSeq, Illumina), evaluated the depletion of these sgRNAs as a proxy for their importance in LINC00963 function. The identification of these key genomic regions that may render LINC00963 non-functional may offer new lncRNA target sites for anti-cancer therapies in the future. Additionally, the utilization of an in-depth CRISPR-Cas9 approach to determine important lncRNA domains provides a novel and precise way in which to evaluate lncRNA function. Citation Format: Roslyn M. Ray, Lu Lang, Sheela P. Pokharel, Denis O'Meally, Tristan A. Scott, Chun-Wei Chen, Kevin V. Morris. The systematic evaluation of the oncogenic lncRNA LINC00963 using a CRISPRScan technique [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2393.

Synaptic damage precedes neuron death in Alzheimer's disease (AD). Neurexins, NRXN1, NRXN2, and NRXN3, are presynaptic adhesion molecules that specify neuron synapses and regulate neurotransmitter release. Neurexins and postsynaptic neuroligins interact with amyloid beta oligomer (AβO) deposits in damaged synapses. NRXN3 gene variants have been associated with autism, addiction, and schizophrenia, however, not fully investigated in Alzheimer's disease. In the present study, we investigated an AD association of a 3'-splicing allele of rs8019381 that produces altered expression of transmembrane or soluble NRXN3 isoforms.We carried out RT-PCR (reverse transcription polymerase chain reaction), PCR-RFLP (PCR and restriction fragment length polymorphism), Sanger sequencing, and in situ hybridization (ISH) assays for NRXN3 neuron expression and genotyping. Genetic associations were analyzed by χWe previously identified a functional haplotype in the 3' region of neurexin 3 (NRXN3) gene that alters the expression ratios between NRXN3 transmembrane and soluble isoforms. In this study, we found that expression and ratio of transmembrane and soluble NRXN3 isoforms were reduced in AD postmortem brains and inversely correlated with inflammasome component NLRP3 in AD brain regions. The splicing haplotype related to the transmembrane and soluble NRXN3 expression was associated with AD samples with P = 6.3 × 10We found that the SNP rs8019381 of NRXN3 that is located adjacent to splicing site #5 (SS#5) interacts with the APOE ε4 haplotype and alters NRXN3 transmembrane or soluble isoform expression in AD postmortem cortex. Dysregulation of presynaptic NRXN3 expression and splicing might increase neuron inflammation in AD brain.

Numerous bacteria, especially pathogens, exist in wastewater final effluents, which can lead to possible human health and ecological security risks when effluents are reused or discharged. However, the diversity, composition, and spatiotemporal dynamics of bacteria in wastewater final effluents remain poorly understood. In this study, a comprehensive analysis of the microbial community and pathogens in wastewater final effluents was performed using high-throughput sequencing. The results revealed that wastewater final effluents in autumn exhibited the highest bacterial community richness and diversity, while those in winter exhibited the lowest. Bacteria in wastewater final effluents predominantly belonged to five phyla, in the order of Proteobacteria, Actinobacteria, Planctomycetes, Bacteroidetes, and Firmicutes. At the species level, there were 8~15 dominant species in the wastewater final effluent in each season, and Dokdonella immobilis, Rhizobium gallicum, Candidatus Flaviluna lacus, and Planctomyces limnophilus were the most dominant species in spring, summer, autumn, and winter, respectively. The seasonal variability in bacteria suggested that the microbial diversity and community in wastewater final effluents were mainly influenced by temperature, salinity, disinfection methods, and flocculants. Notably, pathogenic bacteria in wastewater effluents had both the highest relative abundance and species abundance in summer. Arcobacter spp., Legionella spp., and Mycobacterium spp. were the dominant pathogenic bacteria, and all pathogenic bacteria were mainly associated with dermatosis, enteropathies, septicemia, and pneumonia.

Numerous pathogens exist in treated wastewater, leading to possible population health and ecological security risks when treated waste water is reused or discharged. To investigate the influence of different patterns of discharge on microbial diffusion in the municipal treated waste water, high-throughput sequencing technology was used to analyze the bacterial community structure, dominant flora, and typical pathogens. It was found that those bacteria were distributed in 58 classes. There were 32 species with a relative abundance of more than 1%. While there were only 41 classes in the water sample taken as a direct discharge to the sea, and there were 28 species with relative abundances of more than 1%. The water sample collected as a discharge to the sea through a river displayed higher bacterial diversity than the sample collected as a direct discharge to the sea, indicating that the microorganisms in the treated waste water was more likely to diffuse in when directly discharged to the sea. The relative abundance of dominant bacteria decreased with an increase in the diffusion distance, while the relative abundance of Cyanobacteria increased as the diffusion distance increased. The relative abundance in the water sample collected as a discharge to the sea through a river was higher. The dominant bacteria in the two systems are to Proteobacteria, Bacteroidetes, and Firmicutes. However, the dominant bacteria at the class and species levels quite dissimilar in the two systems. The bacterial diversities near the outfall were much higher than that in the seawater (blank sample), and the abundance was higher, which related to sewage treatment. In addition, there was a certain amount of pathogens and potential pathogens, including

Based on the considerations of an additional angle on the swashplate, the inertia of moving slippers and pistons, the offset between cylinder barrel axis and swashplate rotating axis, the offset between piston ball center and swashplate reference plane, the driving torque model by all slippers on swashplate of the aeronautical hydraulic axial piston pump is created. The numerical calculation for a certain pump is taken as an example. From the result, ignoring inertial force can cause obvious calculation error for the torque. If the offsets are rationally designed, the slippers driving toque can rotating the swashplate to larger angle positon. If the swashplate is rotating, the rotating speed can affect the average value of the slippers driving torque.

Microorganisms play important roles in the reduction of organic and inorganic pollutants in constructed wetlands used for the treatment of wastewater. However, the diversity and structure of microbial community in constructed wetland system remain poorly known. In this study, the Illumina MiSeq Sequencing of 16S rDNA was used to analyze the bacterial and archaeal microbial community structures of soil and water in a free surface flow constructed wetland, and the differences of bacterial communities and archaeal compositions between soil and water were compared. The results showed that the Proteobacteria were the dominant bacteria, making up 35.38%~48.66% relative abundance. Euryarchaeotic were the absolute dominant archaea in the influent sample with the relative abundance of 93.29%, while Thaumarchaeota showed dominance in the other three samples, making up 50.58%~75.70%. The relative abundances of different species showed great changes in bacteria and archaea, and the number of dominant species in bacteria was much higher than that in archaea. Compared to archaea, the community compositions of bacteria were more abundant and the changes were more significant. Meanwhile, bacteria and archaea had large differences in compositions between water and soil. The microbial richness in water was significantly higher than that in soil. Simultaneously, soil had a significant enrichment effect on some microbial flora.

The accuracy reliability problems have long been studied. In order to research ball screw’s accuracy reliability under radical force, some work have done. By using mechanical vibration theory, the dynamic response equation of the beams under external excitation has been derived out. Then by using Matlab, the dynamic response of screw rod under working circumstance is studied, and the dynamic response equation is obtained. At last some calculation examples have given. Results showed that screw’s polar moment of inertia section errors have decisive influences on precision and reliability. By using vibration theory and second moment theory, a new meathod have been proposed in evaluating the ball screw accuracy reliability. Key Words: Screw Transmission; Dynamic Response; Accuracy and Reliability

Background Synaptic damage precedes neuron death in Alzheimer’s disease (AD). Neurexins, NRXN1, NRXN2, and NRXN3, are presynaptic adhesion molecules that specify neuron synapses and regulate neurotransmitter release. Neurexins and postsynaptic neuroligins interact with amyloid beta oligomer (AβO) deposits in damaged synapses. NRXN3 gene variants have been associated with autism, addiction, and schizophrenia, however, not fully investigated in Alzheimer’s disease. In the present study, we investigated an AD association of a 3′-splicing allele of rs8019381 that produces altered expression of transmembrane or soluble NRXN3 isoforms. Methods We carried out RT-PCR (reverse transcription polymerase chain reaction), PCR-RFLP (PCR and restriction fragment length polymorphism), Sanger sequencing, and in situ hybridization (ISH) assays for NRXN3 neuron expression and genotyping. Genetic associations were analyzed by χ 2 tests, and ISH signals were analyzed by FISH v1.0 module of Indica Labs HALO software. Results We previously identified a functional haplotype in the 3′ region of neurexin 3 (NRXN3) gene that alters the expression ratios between NRXN3 transmembrane and soluble isoforms. In this study, we found that expression and ratio of transmembrane and soluble NRXN3 isoforms were reduced in AD postmortem brains and inversely correlated with inflammasome component NLRP3 in AD brain regions. The splicing haplotype related to the transmembrane and soluble NRXN3 expression was associated with AD samples with P = 6.3 × 10−5 (odds ratio = 2.48) and interacted with APOE genotypes. Conclusions We found that the SNP rs8019381 of NRXN3 that is located adjacent to splicing site #5 (SS#5) interacts with the APOE ε4 haplotype and alters NRXN3 transmembrane or soluble isoform expression in AD postmortem cortex. Dysregulation of presynaptic NRXN3 expression and splicing might increase neuron inflammation in AD brain.