Ultra-sensitive fluorescent biosensor for multiple bacteria detection based on CDs/QDs@ZIF-8 and microfluidic fluidized bed.

An ultra-sensitive fluorescent biosensor based on CDs/QDs@ZIF-8 and microfluidic fluidized bed was developed for rapid and ultra-sensitive detection of multiple target bacteria. The zeolitic imidazolate frameworks (ZIF-8) act as the carrier to encapsulate three kinds of fluorescence signal molecules from the CDs/QDs@ZIF-8 signal amplification system. Besides, three kinds of target pathogenic bacteria were automatically, continuously, and circularly captured by the magnetic nanoparticles (MNPs) in the microfluidic fluidized bed. The neutral Na2EDTA solution was the first time reported to not only dissolve the ZIF-8 frameworks from the MNPs-bacteria-CDs/QDs@ZIF-8 sandwich complexes, but also release the CDs/QDs from sandwich complexes with no loss of fluorescence signal. Due to the advantages of signal amplification and automated sample pretreatment, the proposed fluorescent biosensor can simultaneously detect Escherichia coli O157:H7, Salmonella paratyphi A, and Salmonella paratyphi B as low as 101 CFU/mL within 1.5 h, respectively. The mean recovery in spiked milk samples can reach 99.18%, verifying the applicability of this biosensor in detecting multiple bacteria in real samples.

Numerical Simulation on Erosion and Stress on a Small-Diameter Hydrajet Fracturing Tool.

Conventional hydrajet fracturing techniques are often frustrated when they are applied to some specific well types, such as casing-damaged and small-diameter wells. It is of great significance to investigate the erosion and stress on a small-diameter hydrajet fracturing tool during its service and clarify the relevant influencing factors. Based on the solid-liquid two-phase flow theory and erosion model, a numerical simulation was conducted on the erosion and stress on a small-diameter hydrajet fracturing tool by using the computational fluid dynamics approach in order to understand how the inlet flow rate, particle size, and particle mass concentration affect the erosion and stress on the tool. The results show that the erosion on the small-diameter hydrajet fracturing tool is generally a cutting erosion of proppant particles on the tool body. Such erosion occurs on the lower wall of the nozzle, and the erosion at the upper-0° nozzle is higher in rate and smaller in area than that at the lower-180° nozzle. The maximum stress of the small-diameter hydrajet fracturing tool is concentrated on the upper and lower walls of the upper and lower nozzles, especially the lower part inside the upper nozzle. The maximum erosion rate, average erosion rate, and maximum stress on the wall near the nozzle during fracturing increase as the inlet flow rate and particle mass concentration increase and decrease as the proppant particle size increases.

An innovative experimental apparatus for the analysis of natural gas hydrate cavitation erosion process using laser-induced cavitation.

Natural gas hydrates (NGHs) are an emerging source of clean energy distributed in the pores of soil sediments in deep seabed and permafrost zones with abundant reserves. Cavitation contains enormous energy, thus allowing radial cavitation jets to improve drilling and production rates of NGHs. This paper presents an experimental apparatus that was developed to synthesize NGHs and generate cavitation bubbles by laser for the analysis of the erosion rules of NGHs by cavitation in a reservoir environment. The apparatus consists of a working fluid injection and pressure control system, a temperature control and circulation system, a laser-induced cavitation system, a visual reaction vessel, and a data acquisition and measurement system. The laser-induced cavitation erosion on NGHs and multi-bubble interaction experiments can be conducted over temperatures and pressures in the range of 0-20 °C and 0-12 MPa, respectively, in a visualized reaction vessel. Hydrophones and high-speed photography were utilized for monitoring and analyzing the erosion process within the visualized reaction vessel. In addition, bubble groups of different components in various environments can also be tested in this apparatus to obtain the interaction characteristics under different conditions. This paper discusses the basic structure and principle of the apparatus and conducts a series of experiments to verify the effect of cavitation erosion on hydrate and the feasibility of using cavitation to increase production in hydrate exploitation.

An immobilization-free electrochemical biosensor based on CRISPR/Cas13a and FAM-RNA-MB for simultaneous detection of multiple pathogens.

To better respond to biosecurity issues, we need to build good technology and material reserves for pathogenic microorganism screening. Here, we designed an electrochemical/optical signal probe with a common fluorophore and an electrochemically active group, breaking the previous perception that the signal probe is composed of a fluorophore and a quenching group and realizing the response of three signals: electrochemistry, fluorescence, and direct observation. Then, we proposed a homogeneous electrochemical nucleic acid detection system based on CRISPR/Cas named "HELEN-CR" by integrating free electrochemical/optical signal probes and Cas13a cleavage, achieving a limit of detection of 1 pM within 25 min. To improve the detection sensitivity, we applied recombinase polymerase amplification to amplify the target nucleic acid, achieving a limit of detection of 30 zM within 45 min. Complemented by our self-developed multi-chamber microfluidic chip and portable electrochemical instrument, simultaneous detection of multiple pathogens can be achieved within 50 min, facilitating minimally trained personnel to obtain detection results quickly in a difficult environment. This study proposes a simple, scalable, and general idea and solution for the rapid detection of pathogenic microorganisms and biosecurity monitoring.

Ionothermal Synthesis of Novel Layered Magnesium Phosphate and its Tribological Properties as Grease additives.

A novel layered magnesium phosphate (MgP) was synthesised from a MgO-P2 O5 -choline chloride-oxalic acid dihydrate system using an ionothermal approach. Single crystal samples of MgP were obtained following introduction of diethylamine (DEA) to the reaction system. Its structure revealed that both the layer and the sheets contained Mg octahedra. Interestingly, adding the layered material to lithium grease resulted in superior lubrication with higher load-carrying, anti-wear and friction reduction capacities compared with the typical lubricant MoS2 ; the PB value of base grease was increased from 353 to 1078 and 549 N, the wear scar diameter was decreased from 0.50 to 0.34 and 0.46 mm, and the friction coefficient was decreased from 0.082 to 0.056 and 0.075, respectively. We also discuss the lubrication mechanism of layered materials based on the crystal structure and resource endowment. The findings could assist the development of new high-efficiency solid lubricants.

Nomogram Based on Platelet-Albumin-Bilirubin for Predicting Tumor Recurrence After Surgery in Alpha-Fetoprotein-Negative Hepatocellular Carcinoma Patients.

Purpose: In this study, we developed a nomogram based on the platelet-albumin-bilirubin (PALBI) score to predict recurrence-free survival (RFS) after curative resection in alpha-fetoprotein (AFP)-negative (≤20 ng/mL) hepatocellular carcinoma (HCC) patients. Patients and Methods: A total of 194 pathologically confirmed AFP-negative HCC patients were retrospectively analyzed. Univariate and multivariate Cox regression analyses were performed to screen the independent risk factors associated with RFS, and a nomogram prediction model for RFS was established according to the independent risk factors. The receiver operating characteristic (ROC) curve and the C-index were used to evaluate the accuracy and the efficacy of the model prediction. The correction curve was used to assess the calibration of the prediction model, and decision curve analysis was performed to evaluate the clinical application value of the prediction model. Results: PALBI score, MVI, and tumor size were independent risk factors for postoperative tumor recurrence (P < 0.05). A nomogram prediction model based on the independent predictive factors was developed to predict RFS, and it achieved a good C-index of 0.704 with an area under the ROC curve of 0.661 and the sensitivity was 73.2%. Patients with AFP-negative HCC could be divided into the high-risk group or the low-risk group by the risk score calculated by the nomogram, and there was a significant difference in RFS between the two groups (P < 0.05). Decision curve analysis (DCA) showed that the nomogram increased the net benefit in predicting the recurrence of AFP-negative HCC and exhibited a wider range of threshold probabilities than the independent risk factors (PALBI score, MVI, and tumor size) by risk stratification. Conclusion: The nomogram based on the PALBI score can predict RFS after curative resection in AFP-negative HCC patients and can help clinicians to screen out high-risk patients for early intervention.

Dynamic Changes in Microbial Communities, Physicochemical Properties, and Flavor of Kombucha Made from Fu-Brick Tea.

In this study, Fu-brick tea (FBT) was used for kombucha preparation. The succession of microbial community structures, changes in physicochemical properties, and the volatiles were investigated during the kombucha fermentation. The sequencing analysis showed that Komagataeibacter was the most predominant bacterium. Aspergillus and Zygosaccharomyces were the dominant fungi before fermentation whereas Zygosaccharomyces and Derkella were the dominant fungi after 3 days of fermentation. The physicochemical analysis revealed that acetic acid, glucuronic acid, and polyphenols increased by 10.22 g/L, 0.08 g/L, and 177.40 mg/L, respectively, by the end of fermentation. The GC-MS analysis showed that a total of 49 volatile compounds were detected during the fermentation. Moreover, there were great differences in volatile components among the kombucha samples with different fermentation times. Furthermore, the relevance among microbial community and volatile compounds was evaluated through correlation network analysis. The results suggested that Komagataeibacter, Aspergillus, Zygosaccharomyces, and Dekkera were closely related to the main volatile compounds of FBT kombucha. The results in this study may provide deep understanding for constructing the microbiota and improving the quality of FBT kombucha.

Spotlight on clinical strategies of Chronic Internal Carotid Artery Occlusion: Endovascular interventions and external-intracarotid bypasses compared to conservative treatment.

Chronic internal carotid artery occlusion (CICAO) has high prevalence and incidence rates, and patients with CICAO can be completely asymptomatic, experience a devastating stroke or die. It is important to note that CICAO causes cerebrovascular accidents. Currently, the external carotid-internal carotid (EC-IC) bypass technique is used to treat CICAO. However, many clinical studies showed that EC-IC bypass was not beneficial for many patients with CICAO. Meanwhile, endovascular intervention treatment options for CICAO are evolving, and an increasing number of patients are undergoing endovascular intervention therapy. Accordingly, a review comparing both techniques is warranted. For this review, we searched PubMed and collected relevant case study reports comparing endovascular interventional therapy and internal and external cervical bypass surgeries to provide strategies for clinical treatment.

Web-Based TangPlan and WeChat Combination to Support Self-management for Patients With Type 2 Diabetes: Randomized Controlled Trial.

BACKGROUND: China has the largest number of patients with type 2 diabetes mellitus (T2DM) in the world. However, owing to insufficient knowledge of self-management in patients with diabetes, blood glucose (BG) control is poor. Most diabetes-related self-management applications fail to bring significant benefits to patients with T2DM because of the low use rate and difficult operation. OBJECTIVE: This study aims to examine the effectiveness of the combination of the self-designed web-based T2DM management software TangPlan and WeChat on fasting BG (FBG), glycated hemoglobin (HbA1c), body weight, blood pressure (BP), and lipid profiles in patients with T2DM over a 6-month period. METHODS: Participants were recruited and randomized into the TangPlan and WeChat or control groups. Participants in the control group received usual care, whereas the TangPlan and WeChat participants received self-management guidance with the help of TangPlan and WeChat from health care professionals, including BG self-monitoring; healthy eating; active physical exercise; increasing medication compliance; and health education during follow-ups, lectures, or web-based communication. They were also asked to record and send self-management data to the health care professionals via WeChat to obtain timely and effective guidance on diabetes self-management. RESULTS: In this study, 76.9% (120/156) of participants completed the 6-month follow-up visit. After the intervention, FBG (mean 6.51, SD 1.66 mmol/L; P=.048), HbA1c (mean 6.87%, SD 1.11%; P<.001), body weight (mean 66.50, SD 9.51 kg; P=.006), systolic BP (mean 127.03, SD 8.00 mm Hg; P=.005), diastolic BP (mean 75.25, SD 5.88 mm Hg; P=.03), serum low-density lipoprotein cholesterol (mean 2.50, SD 0.61 mmol/L; P=.006), and total cholesterol (mean 4.01, SD 0.83 mmol/L; P=.02) in the TangPlan and WeChat group were all significantly lower, whereas serum high-density lipoprotein cholesterol (mean 1.20, SD 0.25 mmol/L; P=.01) was remarkably higher than in those in the control group. Compared with the baseline data, significance was found in the mean change in FBG (95% CI -0.83 to -0.20; P=.002), HbA1c (95% CI -1.92 to -1.28; P<.001), body weight (95% CI -3.13 to -1.68; P<.001), BMI (95% CI -1.10 to -0.60; P<.001), systolic BP (95% CI -7.37 to -3.94; P<.001), diastolic BP (95% CI -4.52 to -2.33; P<.001), triglycerides (95% CI -0.16 to -0.03; P=.004), serum low-density lipoprotein cholesterol (95% CI -0.54 to -0.30; P<.001), and total cholesterol (95% CI -0.60 to -0.34; P<.001) in the TangPlan and WeChat group but not in the control group (P=.08-.88). CONCLUSIONS: Compared with usual care for patients with T2DM, the combination of TangPlan and WeChat was effective in improving glycemic control (decrease in HbA1c and BG levels) and serum lipid profiles as well as reducing body weight in patients with T2DM after 6 months. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000028843; https://tinyurl.com/559kuve6.

Healthcare needs, experiences and treatment burden in primary care patients with multimorbidity: An evaluation of process of care from patients' perspectives.

BACKGROUND: Patients with multimorbidity often experience treatment burden as a result of fragmented, specialist-driven healthcare. The 'family doctor team' is an emerging service model in China to address the increasing need for high-quality routine primary care. OBJECTIVE: This study aimed to explore the extent to which treatment burden was associated with healthcare needs and patients' experiences. METHODS: Multisite surveys were conducted in primary care facilities in Guangdong province, southern China. Interviewer-administered questionnaires were used to collect data from patients (N = 2160) who had ≥2 clinically diagnosed long-term conditions (multimorbidity) and had ≥1 clinical encounter in the past 12 months since enrolment registration with the family doctor team. Patients' experiences and treatment burden were measured using a previously validated Chinese version of the Primary Care Assessment Tool (PCAT) and the Treatment Burden Questionnaire, respectively. RESULTS: The mean age of the patients was 61.4 years, and slightly over half were females. Patients who had a family doctor team as the primary source of care reported significantly higher PCAT scores (mean difference 7.2 points, p < .001) and lower treatment burden scores (mean difference -6.4 points, p < .001) when compared to those who often bypassed primary care. Greater healthcare needs were significantly correlated with increased treatment burden (ß-coefficient 1.965, p < .001), whilst better patients' experiences were associated with lower treatment burden (ß-coefficient -0.252, p < .001) after adjusting for confounders. CONCLUSION: The inverse association between patients' experiences and treatment burden supports the importance of primary care in managing patients with multimorbidity. PATIENT CONTRIBUTION: Primary care service users were involved in the instrument development and data collection.

Body Constitution and Unhealthy Lifestyles in a Primary Care Population at High Cardiovascular Risk: New Insights for Health Management.

BACKGROUND: Adherence to lifestyle recommendations remains insufficient in cardiovascular (CV) health management globally. Body constitution, from the perspective of traditional Chinese medicine, is primarily influenced by an individual's internal metabolism and susceptibility to external pathogenic factors. Nevertheless, less is known about whether body constitutions may play a role in the presence of unhealthy lifestyles. We aimed to explore the associations between body constitutions and unhealthy lifestyles among Chinese individuals at high CV risk. METHODS: Computerised data were retrieved from a primary care population-based health record for all 1739 eligible individuals at high CV risk who attended routine check-up in an urbanised, medium-size district in Guangzhou, China. Unhealthy lifestyles were determined in accordance with guideline recommendations. The body constitution was assessed on the basis of physical signs, personality, body symptoms, and the susceptibility to environmental changes, following nationally standard procedure. Binary logistic regression analyses were performed using marginal standardisation method. RESULTS: The participants ranged in age from 20 to 96 years, with a mean age of 69.55 years. There were slightly more females than males (52.3% vs 47.7%). Current smoking, regular drinking, and physical inactivity were most common. Participants with a body constitution of phlegm-and-dampness type (adjusted odds ratio [aOR]=1.999, 95% confidence interval [CI]=1.003-3.984; p=0.049) tended to be current smokers, and those assessed with special diathesis type (aOR=2.166, 95% CI=1.029-4.559; p=0.042) had a higher likelihood of being regular drinkers. Having a body constitution type of blood stasis (aOR=1.375, 95% CI=1.029-1.838; p=0.031) or qi deficient (aOR=1.711, 95% CI=1.080-2.709; p=0.022) was associated with physical inactivity. CONCLUSION: Our findings add to current evidence suggesting that an individual's body constitution is closely related to the presence of unhealthy lifestyles. This offers new insights for health management through body constitution-based strategies to target those at high CV risk who need tailor-made attention in lifestyle modifications during routine primary care.

An innovative experimental apparatus for the analysis of natural gas hydrate erosion process using cavitating jet.

Natural Gas Hydrate (NGH) develops and exists in pores of soil sediments under deep seabed and permafrost regions. A cavitation jet is an efficient method of rock breaking, especially for soft hydrate sediment erosion. This paper presents an experimental apparatus that was developed to synthesize NGH and hydrate-bearing sediments and analyze the drilling efficiency of the cavitation jet. The visualization study of fluid flow and breaking mechanism can be conducted over a temperature range varying from -20 °C to 100 °C and up to a maximum confining pressure of 20 MPa. This apparatus is mainly composed of the pressure control and injection system, the cooling system, the cavitation system, and the reaction vessels into which the lab-fabricated temperature/pressure/resistivity sensor probe is inserted. The basic principles of this apparatus are discussed, and a series of experiments were performed to verify that the cavitating jet can be practically applied in the exploitation of NGH reservoirs.

Expression of Cripto-1 in the placenta and its role in placenta accreta and placenta previa.

OBJECTIVES: This study Aims to explore the role of placental Cripto-1 in the incidence of an adherent placenta. MATERIAL AND METHODS: Ten pregnant women with placenta increta, 20 pregnant women with placenta previa and 30 women with normal pregnant were enrolled in this study. Reverse transcription-polymerase chain reaction (RT-PCR) was used to measure the expression of Cripto-1 in the placenta while as the analysis of placental Cripto-1 was performed by Western blotting RESULTS: The placenta increta group showed higher levels of Cripto-1 in the center of the increta as compared to the non-implantation area. The level of placental Cripto-1 in the placenta increta was higher than that of the placenta accrete. The expression of placental Cripto-1 in the placenta increta and placenta previa groups was higher than that of control. CONCLUSIONS: Placental Cripto-1 is involved in the regulation of placental tissue invasion. Additionally, excessive placental growth or penetration into the myometrium are likely to be involved in the development of placenta increta.

Size-Dependent Memory Effect of the LiFePO4 Electrode in Li-Ion Batteries.

In Li-ion batteries, the phase transition usually determines the electrochemical kinetics of some two-phase electrode materials, and it can be adopted to excellently interpret the memory effect of Li-ion batteries, therefore the size dependence of phase transition was expected to affect the memory effect significantly. In this work, we investigated the memory effect and phase transition of olivine LiFePO4 in Li-ion batteries. Through electrochemical measurements, we found that the memory effect of LiFePO4 was dependent on the particle size, especially after a long-time relaxation. By using the in situ X-ray diffraction, we found that the phase transition of nano-LiFePO4 was ahead of the charging and discharging processes, while it took place concurrently or later for micro-LiFePO4, which might be attributed to the high-specific two-phase boundary of nano-LiFePO4. Furthermore, the phase-transition diagram was adopted to interpret the size-dependent memory effect schematically. Notably, it is the first time to report the phase transition ahead of (dis)charging for nano-LiFePO4, which is significant to understand the phase transition of two-phase electrode materials, as well as the relevant phenomena, such as the memory effect.

Mitochondrial genome of Stachyris ruficeps (Aves, Passeriformes, Timaliidae).

Stachyris ruficeps are commonly found in the eastern Himalayas and south China. In our study, we reported the complete mitogenome and obtain basic genetic information of S. ruficeps for the first time. The complete mitochondrial genomes of S. ruficeps (16 885bp in length) had 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes (12S rRNA and 16S rRNA) and 2 control regions. All of the 13 PCGs were initiated by ATG. All the genes in S. ruficeps were distributed on the H-strand, except for the ND6 gene and eight tRNA genes which were encoded on the L-strand.

Extraction of a soluble polysaccharide from Auricularia polytricha and evaluation of its anti-hypercholesterolemic effect in rats.

Mushroom extracts are a new source of supplements for health and pharmaceutical due to their bioactivities. This study was to optimize the extraction parameters of a soluble polysaccharide from Auricularia polytricha (SPAP) by response surface methodology. The practical optimum parameters were an extraction time of 4h, an extraction temperature of 95 °C and a ratio of water to fruiting bodies of 28 mL/g, and the highest extraction rate was 19.77%. In vivo, male Sprague-Dawley (SD) rats were diet-induced hypercholesterolemic models and oral administration of SPAP to evaluate anti-hypercholesterolemic effects. The results showed that SPAP decreased the serum concentrations of blood lipid, made them close to the normal level. The total cholesterol in the SPAP consumption groups was significantly decreased 34.6 ± 7.6% and 33.3 ± 7.9% with dose of 4.5 and 9.0mg/kg BW in the 29th day. This study suggested that SPAP was a suitable natural agent and may be applied in therapy.