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Gut microbiota plays an important role in health and metabolism and is affected by diet. This means that the gut microbiota of sympatric species is different due to niche separation. In this study, high-throughput 16S rRNA sequencing was used to study the gut microbiota of sympatric François’ langurs and rhesus macaques using 57 fecal samples collected from the limestone forests of the Guangxi Chongzuo White-headed Langur National Nature Reserve. The results indicated no significant difference in gut microbial diversity between the two primate species. However, marked differences were found in gut microbial composition. François’ langurs had a greater abundance of Firmicutes, Verrucomicrobia, TM7, and Planctomycetes, and a lower abundance of Bacteroidetes, Tenericutes, Proteobacteria, WPS-2, Fibrobacteres, and Lentisphaerae than rhesus macaques. At the genus level, François’ langurs had a greater abundance of norank Ruminococcaceae, unclassified Clostridiales, norank Clostridiales, Akkermansia, and unclassified Ruminococcaceae, whereas macaques had a higher proportion of Prevotella, Coprococcus, and Oscillospira. Predictive functional analysis reveals that the gut microbiota of François’ langurs is richer in cellular processes pathways than that of rhesus macaques, which were richer in genetic information processing and organismal systems. In summary, significant differences in gut microbiota were evident between the two sympatric primate species, which is probably due to the diet separation and morphology of the digestive tract. This suggests niche separation between the sympatric limestone-dwelling rhesus macaques and François’ langurs.

Abstract The gut microbiota plays an important role in animal health and is strongly affected by the environment. Captivity and human source food have been shown to influence drastically the gut microbiota composition and function of wild animals. Therefore, in the present study, the gut microbiota of provisioned and wild populations of limestone‐living rhesus macaques (Macaca mulatta) were compared using high‐throughput 16S rRNA sequencing and bioinformatic analyses. The results indicated that provisioned macaques had a higher microbial richness than wild macaques, but there was no significant difference in the evenness of the gut microbiota between the two populations. Provisioned macaques also showed a higher abundance of Firmicutes and a lower abundance of Bacteroidetes than wild macaques. Functional analysis revealed that wild macaques had enriched microbial pathways involved in glycan biosynthesis and metabolism, transport and catabolism, and the digestive and endocrine systems, while provisioned macaques were richer in pathways associated with signaling molecules and interaction, neurodegenerative diseases. These differences were likely due to modification of the gut microbiota of the provisioned macaques to enable the digestion of new foods.

Background: In recent years, some miRNAs have been reported to be connected closely with the development of human hepatocellular carcinoma. In our previous studies, a set of miRNAs were revealed to be dysregulated in HCC tissues. However, the functions of these miRNAs in HCC remain largely undefined. Methods: The expression profiles of miR-183 were compared between HCC tissues and adjacent normal liver tissues using qRT-PCR method. This method was used to screen the potential target genes of miR-183. A luciferase reporter assay was conducted to confirm target association. Finally, the functional effect of miR-183 in hepatoma cells was examined. Results: Among the 25 HCC samples analyzed, microRNA-183 was significantly up-regulated (twofold to 367-fold) in 17 samples compared with the matching nontumoral liver tissues. Programmed cell death 4 (PDCD4) was identified as the target gene of miR-183. Moreover, PDCD4 is a proapoptotic molecule involved in TGF-β1-induced apoptosis in human HCC cells, we found that miR-183 transfectants were resistant to apoptosis induced by TGF-β1. Conclusions: We conclude that miR-183 can inhibit apoptosis in human HCC cells by repressing the PDCD4 expression, and miR-183 may play an important role in HCC development. [ABSTRACT FROM AUTHOR]

A CMOS analog baseband transceiver with a 13-bit, 180 MSPS pipelined ADC and dual 12-bit, 180 MSPS current-steering DACs is presented. The ADC is implemented without a dedicated track-and-hold stage, utilizes a front-end 2.5-bit stage with matched MDAC/comparator tracking circuits, and demonstrates an ENOB of 10.6 bits at 15 MHz and 9.7 bits at 100 MHz, employing a low-jitter delay-lock loop for its phasing. The dual I/Q DACs show over 62 dB SFDR over the Nyquist band by utilizing a dynamic linearity enhancing architecture. [ABSTRACT FROM AUTHOR]

An ultra-low-voltage CMOS two-stage algorithm ADC featuring high SFDR and efficient background calibration is presented. The adopted low-voltage circuit technique achieves high-accuracy high-speed clocking without the use of clock boosting or bootstrapping. A resistor-based input sampling branch demonstrates high linearity and inherent low-voltage operation. The proposed background calibration accounts for capacitor mismatches and finite opamp gain error in the MDAC stages via a novel digital correlation scheme involving a two-channel ADC architecture. The prototype ADC, fabricated in a 0.18 µm CMOS process, achieves 77-dB SFDR at 0.9 V and 5 MSPS (30 MHz clocking) after calibration. The measured SNR, SNDR, DNL, and INL at 80 kHz input are 50 dB, 50 dB, 0.6 LSB, and 1.4 LSB, respectively. The total power consumption is 12 mW, and the active die area is 1.4 mm². [ABSTRACT FROM AUTHOR]

A time-shifted correlated double sampling (CDS) technique is proposed in the design of a 10-bit 100-MS/s pipelined ADC. This technique significantly reduces the finite opamp gain error without compromising the conversion speed, allowing the active opamp blocks to be replaced by simple cascoded CMOS inverters. Both high-speed and low-power operation is achieved without compromising the accuracy requirement. An efficient common-mode voltage control is introduced for pseudodifferential architecture which can further reduce power consumption. Fabricated in a 0.18-µm CMOS process, the prototype 10-bit pipelined ADC occupies 2.5 mm² of active die area. With 1-MHz input signal, it achieves 65-dB SFDR and 54-dB SNDR at 100 MS/s. For 99-MHz input signal, the SFDR and SNDR are 63 and 51 dB, respectively. The total power consumption is 67 mW at 1.8-V supply, of which analog portion consumes 45 mW without any opamp current scaling down the pipeline. [ABSTRACT FROM AUTHOR]

Presents the details of a fast and accurate correlation-based background digital calibration scheme in the context of a 1.5-bit-per-stage pipelined or cyclic analog-to-digital converters architecture. Capacitor mismatch; Digital redundancy; Pseudorandom noise sequence.

High-temperature superconducting (HTS) maglev, owning to the capability of passive stabilization, is potentially promising for high-speed transportation. The guidance force of bulk HTS materials above a permanent magnetic guideway has a nonlinear response due to the hysteresis effect. As a kind of rail transit, when the vehicle runs along the track, the curve and other disturbances will cause vibrations to the vehicle system. These physical factors will pose dynamic loads on the components, reducing structural reliability as well as affecting the ride comfort. The lateral motion, as an important part of the vehicle system dynamics, needs to be studied in the pursuit of HTS maglev realization. In this paper, we first measured the guidance forces of HTS bulks under different motion conditions, and analyzed the relationship between the lateral displacement, the movement velocity and the guidance force. Then, a mathematical model was built based on these experimental data. The key feature of this mathematical model is that it can describe the hysteresis characteristic of the guidance force. Based on this model, we investigated the lateral motion stability of the HTS levitation system, and found three singular points, one stable focus point, and two unstable saddle points. Lastly, a phase portrait was proposed to indicate the safe working region of the HTS maglev vehicle where the vehicle can automatically return to its equilibrium position. These experimental and simulation results are important to clarify the lateral motion stability under external disturbance or shock, and provide a reference basis for the design of levitation systems. [ABSTRACT FROM AUTHOR]

Objective: The systemic inflammation index and body mass index (BMI) are easily accessible markers that can predict mortality. However, the prognostic value of the combined use of these two markers remains unclear. The goal of this study was therefore to evaluate the association of these markers with outcomes based on a large cohort of patients with gastric cancer. Methods: A total of 2,542 consecutive patients undergoing radical surgery for gastric or gastroesophageal junction adenocarcinoma between 2009 and 2014 were included. Systemic inflammation was quantified by the preoperative neutrophil-to-lymphocyte ratio (NLR). High systemic inflammation was defined as NLR ≥ 3, and underweight was defined as BMI < 18.5 kg/m². Results: Among 2,542 patients, NLR ≥ 3 and underweight were common [627 (25%) and 349 (14%), respectively]. In the entire cohort, NLR ≥ 3 or underweight independently predicted overall survival (OS) [hazard ratio (HR): 1.236, 95% confidence interval (95% CI): 1.069-1.430; and HR: 1.600, 95% CI: 1.350-1.897, respectively] and recurrence-free survival (RFS) (HR: 1.230, 95% CI: 1.054-1.434; and HR: 1.658, 95% CI: 1.389-1.979, respectively). Patients with both NLR ≥ 3 and underweight (vs. neither) had much worse OS (HR: 2.445, 95% CI: 1.853-3.225) and RFS (HR: 2.405, 95% CI: 1.802-3.209). Furthermore, we observed similar results in subgroup analyses according to pathological stage, age, and postoperative chemotherapy. Conclusions: Our results showed that preoperative elevated NLR and decreased BMI had a significant negative effect on survival. Underweight combined with severe inflammation could enhance prognostication. Taking active therapeutic measures to reduce inflammation and increase nutrition may help improve outcomes. [ABSTRACT FROM AUTHOR]

Objective: To employ three-dimensional finite element modeling and biomechanical simulation for evaluating the stability and stress conduction of two postoperative internal fixed modeling-multilevel posterior instrumentation ( MPI) and MPI with anterior instrumentation (MPAI) with neck-thoracic vertebral tumor en bloc resection., Methods: Mimics software and computed tomography (CT) images were used to establish the three-dimensional (3D) model of vertebrae C5-T2 and simulated the C7 en bloc vertebral resection for MPI and MPAI modeling. Then the statistics and images were transmitted into the ANSYS finite element system and 20N distribution load (simulating body weight) and applied 1 N · m torque on neutral point for simulating vertebral displacement and stress conduction and distribution of motion mode, i. e. flexion, extension, bending and rotating., Results: With a better stability, the displacement of two adjacent vertebral bodies of MPI and MPAI modeling was less than that of complete vertebral modeling. No significant differences existed between each other. But as for stress shielding effect reduction, MPI was slightly better than MPAI., Conclusion: From biomechanical point of view, two internal instrumentations with neck-thoracic tumor en bloc resection may achieve an excellent stability with no significant differences. But with better stress conduction, MPI is more advantageous in postoperative reconstruction.