Coherently parallel fiber-optic distributed acoustic sensing using dual Kerr soliton microcombs.

Fiber-optic distributed acoustic sensing (DAS) has proven to be a revolutionary technology for the detection of seismic and acoustic waves with ultralarge scale and ultrahigh sensitivity, and is widely used in oil/gas industry and intrusion monitoring. Nowadays, the single-frequency laser source in DAS becomes one of the bottlenecks limiting its advance. Here, we report a dual-comb-based coherently parallel DAS concept, enabling linear superposition of sensing signals scaling with the comb-line number to result in unprecedented sensitivity enhancement, straightforward fading suppression, and high-power Brillouin-free transmission that can extend the detection distance considerably. Leveraging 10-line comb pairs, a world-class detection limit of 560 fε/√Hz@1 kHz with 5 m spatial resolution is achieved. Such a combination of dual-comb metrology and DAS technology may open an era of extremely sensitive DAS at the fε/√Hz level, leading to the creation of next-generation distributed geophones and sonars.

Ultrafast Detection and Discrimination of Methanol Gas Using a Polyindole-Embedded Substrate Integrated Waveguide Microwave Sensor.

The fast and sensitive detection of methanol gas using cost-effective sensors in the industry is a significant issue to be addressed. Herein, a polyindole (PIn)-deposited substrate integrated waveguide (SIW) has been introduced to perform quantitative and qualitative methanol gas sensing with quick response and recovery time at room temperature. First, PIn is synthesized and deposited in the microwell etched at the intensified electric field region of the microwave-based cavity resonator, which gives a sensing response through variation of PIn's high-frequency conductivity and dielectric property caused by the adsorption and desorption of methanol gas. Second, an enhanced filling factor and high Q factor have been attained using the proposed microwell etched SIW structure, which exhibits high sensitivity in terms of frequency shift (3.33 kHz/ppm), amplitude shift (0.005 dB/ppm), bandwidth broadening (3.66 kHz/ppm), and loaded Q factor (10.60 Q value/ppm). Third, the gas measurement results reveal excellent long-term stability with a relative standard deviation (RSD) of 0.02% for 7 days, excellent repeatability with an RSD of 0.004%, and desired response and recovery time of 95 and 120 s, respectively. The results indicate that the proposed microwave sensor has great potential to achieve high sensitivity and fast response toward methanol gas molecules at room temperature.

High-Sensitivity, Quantified, Linear and Mediator-Free Resonator-Based Microwave Biosensor for Glucose Detection.

This article presents a high-sensitivity, quantified, linear, and mediator-free resonator-based microwave biosensor for glucose sensing application. The proposed biosensor comprises an air-bridge-type asymmetrical differential inductor (L) and a center-loaded circular finger-based inter-digital capacitor (C) fabricated on Gallium Arsenide (GaAs) substrate using advanced micro-fabrication technology. The intertwined asymmetrical differential inductor is used to achieve a high inductance value with a suitable Q-factor, and the centralized inter-digital capacitor is introduced to generate an intensified electric field. The designed microwave sensor is optimized to operate at a low resonating frequency that increases the electric field penetration depth and interaction area in the glucose sample. The microwave biosensor is tested with different glucose concentrations (0.3-5 mg/ml), under different ambient temperatures (10-50 °C). The involvement of advanced micro-fabrication technology effectively miniaturized the microwave biosensor (0.006λ0 × 0.005λ0) and enhanced its filling factor. The proposed microwave biosensor demonstrates a high sensitivity of 117.5 MHz/mgmL-1 with a linear response (r2 = 0.9987), good amplitude variation of 0.49 dB/mgmL-1 with a linear response (r2 = 0.9954), and maximum reproducibility of 0.78% at 2 mg/mL. Additionally, mathematical modelling was performed to estimate the dielectric value of the frequency-dependent glucose sample. The measured and analyzed results indicate that the proposed biosensor is suitable for real-time blood glucose detection measurements.

Eating problems and associated factor among 1 873 preschool children in Hefei / 中国学校卫生

Objective@#To explore the prevalence of eating problems of preschool children in Hefei and its influencing factors, and to provide references for reducing the occurrence of dietary behavior problems of local children and strengthening the construction of children nutrition clinic in maternal and children health care institutions.@*Methods@#A total of 1 873 children aged 3-6 years in urban and rural areas of Hefei were selected by random cluster sampling. Demographic and eating behavior of the child, as well as caregiver’s feeding behavior were investigated.@*Results@#The study found that 72.77% of children had eating problems. The feeding behavior of feeders and the family environment factors had an impact on children’s eating behavior problems, and the main influencing factors of children’s eating behavior included father’s education level, family economic monthly income level, family members’ eating behavior problems, number of children living together and whether they are the only-child in the family(P<0.05).@*Conclusion@#The prevalence of eating problems of children aged 3-6 years in Hefei is higher. Family demographic, caregiver feeding behavior, as well as the environment of the family affect children’s eating behavior. Child nutrition clinics, promotion of caregivers’feeding practices could be effective interventions aiming to address eating problems among preschool children.

Neuroprotective effect of baicalin on focal cerebral ischemia in rats.

Baicalin, a flavonoid compound from the root of the herb Scutellaria baicalensis Georgi, has been widely used to treat patients with inflammatory disease. The aim of this study was to assess the efficacy of baicalin in a rat model of focal cerebral ischemia. Adult male Sprague-Dawley rat models of cerebral artery occlusion were established and then randomly and equally divided into three groups: ischemia (cerebral ischemia and reperfusion), valproic acid (cerebral ischemia and reperfusion + three intraperitoneal injections of valproic acid; positive control), and baicalin (cerebral ischemia and reperfusion + intraperitoneal injection of baicalin for 21 days). Neurological deficits were assessed using the postural reflex test and forelimb placing test at 3, 7, 14, and 21 days after ischemia. Rat cerebral infarct volume was measured using 2,3,5-triphenyltetrazolium chloride (TTC) staining method. Pathological change of ischemic brain tissue was assessed using hematoxylin-eosin staining. In the baicalin group, rat neurological function was obviously improved, cerebral infarct volume was obviously reduced, and the pathological impairment of ischemic brain tissue was obviously alleviated compared to the ischemia group. Cerebral infarct volume was similar in the valproic acid and baicalin groups. These findings suggest that baicalin has a neuroprotective effect on cerebral ischemia.

Antitumor activity of extracts from rabbit skins inflamed by Viccinia virus vaccine in vitro / 国际药学研究杂志

Objective To investigate the effect of extracts from rabbit skins inflamed by Viccinia virus vaccine (analgecine) on the proliferation of human cancer cells and on the cytokine secretion in mouse spleen lymphocytes in vitro. Methods Five human tumor cell lines, HepG2, LM3, H460, A549 and HeLa were used and the effect of analgecine (1.63, 0.815, 0.326, 0.163 and0.0815 U/ml) on the cell proliferation was evaluated by the CCK-8 assay. The mouse spleen was isolated aseptically, and the spleen lymphocyte suspension was prepared and cultured with PRMI-1640 medium containing 10％ fetal bovine serum (FBS). For detection of the cytokine IL-2, IFN-γ, IL-4 and IL-12 level, the stimulant concanavalin A (ConA) or lipoplysaccharide (LPS) was added into the lymphocyte suspension, and the lymphocytes were cultured under the presence of analgecine at the final concentration of 0.815, 0.163 and 0.0815 U/ml for 24 hours. Then, the level of the cytokines in the supernatant was detected by the ELISA kit. On the other hand, the effect of supernatant of the spleen lymphocyte cultures under the presence of analgecine at 0.815 U/ml on the proliferation HepG2 cells was also evaluated by the CCK-8 assay. The CCK-8 assay was performed after cultivation of the HepG2 cells in the whole supernatant or in its dilution with fresh medium for 24 hours. Results Analgecine showed a dose-dependent inhibitory effect on the five tested cancer cell lines, with the inhibition rate of 58.95％, 55.08％, 57.28％, 45.80％ and 48.18％ at the 1.63 U/ml on the HepG2, LM3, H460, A549 and HeLa cells, respectively. Compared with the control group, the secretion of IL-2, IFN-γ and IL-4 was significantly increased in the 0.163 and 0.815 U/ml analgecine groups (P＜0.01), while the secretion level of IL-12 was increased in the 0.0815, 0.163 and 0.815 U/ml analgecine groups (P＜0.01). The supernatant of the mouse spleen lymphocyte cultures under the presence of0.163 U/ml analgecine could inhibit the HepG2 cell proliferation in a dose-dependent manner, and the inhibitory effect of the whole supernatant was significantly stronger than the effect of the same concentration analgecine 0.163 U/ml (P＜0.01). Conclusion Analgecine could inhibit the cell proliferation of the tested five human cancer cell lines, increased the secretion of IL-2, IFN-γ, IL-4 and IL-12 cytokines in mouse spleen lymphocytes, all in vitro, and its effect on the cytokine secretion may be related to the inhibitory effect on the human cancer cell proliferation.

Effect of omeprazole on antiplatelet activities of W1 / 国际药学研究杂志

Objective To investigate the antiplatelet effects of candidate drug W1 when combined with omeprazole,respec?tively.Methods The experimental rats were randomly divided into 5 groups:control group,clopidogrel(10 mg/kg)group,clopido?grel(10 mg/kg)+omeprazole(80 mg/kg)group,W1(3 mg/kg)group,and W1(3 mg/kg)+omeprazole(80 mg/kg)group.Four hours after oral administration of the drugs,the rats were measured for their platelet aggregation rate;Western blot was used to deter?mine the protein expressions of P2Y12 receptor,P-Akt and P-Erk.Results For the platelet aggregation rate,compared with the con?trol group,the 4 groups decreased significantly(P<0.01);the platelet aggregation rate in the clopidogrel + omeprazole group in?creased significantly than that in the clopidogrel group(42% and 20.4%,respectively,P<0.01);the platelet aggregoction rate (30.9%)in W1+omeprazole group was significantly higher(P<0.01)than that in the W1 group(20.5%),which was lower than that in the clopidogrel+omeprazole group(P<0.01).For the protein expression detected by the western blotting,there were no signif?icant changes in the expression of P2Y12 receptor on the platelet surface,in the clopidogrel or W1 group in comparison with the clopi?dogrel+omeprazole or W1+omeprazole group,respectively,while the phosphorylation level of Akt and Erk was up-regulated in the clopidogrel+omeprazole or W1+omeprazole group compared with the clopidogrel or W1 group,and the up-ragulatory effect of omepra?zole was weaker in the W1+omeprazole group than that in the clopidogrel+omeprazole group. Conclusion Combined use of omepra?zole could inhibit the antiplatelet activities of clopidogrel or W1,with the inhibitory effect weaker in W1 group than in clopidogrel group,suggesting that the risk for the combination of omeprazole with W1 is likely less than that for the combination with clopidogrel.