Mechanical effects of needle texture on acupoint tissue.

OBJECTIVE: This study aims to clarify how the stimulation of acupuncture points is achieved by needles with different surface texture during acupuncture; it also seeks to lessen injury at the insertion site and increase the therapeutic efficacy of acupuncture, by simulating the mechanical effects of various needle surface patterns on Zusanli (ST36) without changing the radius of acupuncture needles. METHODS: Five acupuncture needle models with different surface patterns, including the smooth needle, the lined needle, the ringed needle, the left-hand threaded needle and the right-hand threaded needle, and a layered model of the Zusanli acupoint were used to investigate how to reduce tissue damage and increase stimulation during acupuncture treatment. Puncturing of the skin as well as lifting-inserting and twisting needle manipulations were simulated using these models, and the degree of damage and force of stimulation caused by the acupuncture needles with different surface patterns during acupuncture were compared. RESULTS: The smooth needle and the lined needle caused the least tissue damage during insertion, while the left-hand threaded and the right-hand threaded needles caused the most damage. The ringed needle, the left-hand threaded needle and the right-hand threaded needle stimulated the acupoint tissue more during lifting-inserting manipulations, while the lined needle and the smooth needle produced less stimulation. The stimulation of the lined needle on the acupoint tissue was the largest during twisting manipulation, whereas the left-hand threaded needle and the right-hand threaded needle had smaller effects. In lifting-inserting and twisting manipulations, both the left-hand threaded needle and right-hand threaded needle provided more stimulation, but the torsion direction in which they produced better stimulation was the opposite. CONCLUSION: According to the simulation results, the ringed pattern enhances stimulation best in the lifting-inserting manipulation, whereas the lined pattern enhances stimulation best in the twisting manipulation. Both the right-hand and left-hand thread patterns have certain enhancing effects in these two operations. Taking the geometric properties of the pattern into account, the left-hand thread pattern and the right-hand thread pattern have the geometric characteristics of both the lined pattern and the ringed pattern. To conclude, a pattern perpendicular to the movement direction during the acupuncture manipulation creates more stimulation. These results have significance for future needle design. Please cite this article as: Sun MZ, Wang X, Li YC, Yao W, Gu W. Mechanical effects of needle texture on acupoint tissue. J Integr Med. 2023; 21(3): 254-267.

Polyelectrolyte Bilayer-Based Transparent and Flexible Memristor for Emulating Synapses.

Memristors will be critical components in the next generation of digital technology and artificial synapses. Researchers are investigating innovative mechanistic understanding of the memristor devices based on low-cost, solution-processable, and organic materials as promising candidates. Here, we demonstrate a novel polyelectrolyte-based memristor device, which is simply prepared by spin-coating poly(acrylic acid) (PAA) and polyethylenimine (PEI) on an indium tin oxide (ITO) substrate followed by a magnetron sputtering of the ITO as the top electrode. The device has a potential to achieve excellent resistive switching (RS) performance and synapse functionality as well as greater flexibility and transmittance when compared to the oxide-based memories. An on/off resistance ratio of 50 can be maintained without degradation for up to 20 000 cycles (flat state) and over 4000 cycles (bending to a 2 mm radius 10 000 times) in the DC sweep mode. Moreover, the device performs various synaptic functions, including spike-timing-dependent plasticity, pulse pair plasticity, and short-term and long-term plasticity in the potentiation and depression processes. The counterions and two oppositely charged polyelectrolyte chains can move in and out of each other depending on the applied electrical potential (pulse), resulting in a change in the potential drop at the interface of the polyelectrolyte bilayer and its electrodes, which can be attributed to the RS mechanism and various synaptic functions. This insight may accelerate the technological deployment of the organic resistive memories.

CRA(Crosolic Acid) isolated from Actinidia valvata Dunn.Radix induces apoptosis of human gastric cancer cell line BGC823 in vitro via down-regulation of the NF-κB pathway.

A natural ursolic compound, 2α,3ß-dihydroxy-urs-12-en-28-oic acid (corosolic acid, CRA) was isolated from the root of Actinidia valvata Dunn. (A. valvata Radix). Since a large number of triterpenoid compound has marked anticancer effects toward various types of cancer cell lines in vitro, this study was carried out to investigate the anticancer effect of CRA in human gastric cancer cell line BGC823 cells and the underlying apoptotic mechanism of CRA was examined in BGC823 cell lines. The results showed that CRA significantly suppressed the viability of BGC823 cells in a concentration- and time-dependent manner. CRA also significantly increased the sub G1 population by cell cycle analysis in a concentration dependent manner. Exposure to CRA decreased p65, bcl-2, Fas, smac mRNA and protein expression, and increased IκBα, bax, survivin mRNA and protein expression. Results of immunofluorescence staining and EMSA further indicated CRA induced apoptosis by inhibiting nuclear translocation of nuclear factor NF-κB subunit p65. Consistently overall, our findings suggest that CRA induces apoptosis via inhibition of NF-κB (p65) expression level and activation of IκBα in BGC cells as a potent anticancer candidate for gastric cancer treatment.

[Characteristics of Dissolved CH4 and N2O Concentrations of Weihe River in Xinxiang Section in Spring].

Distributions of CH4 and N2O concentrations in Weihe River in Xinxiang City were monitored in spring of 2015, and their influencing factors were discussed. The result showed that CH4 and N2O were super-saturated in surface water of Weihe River. The variation ranges of two gases' saturations in the surface water of Weihe River were 147.59-2667.85 (CH4) and 4.06-188.25 (N2O). In the urban area, significant correlation existed between N2O and NH4⁺-N concentrations (P < 0.01), but in the new district, dissolved N2O concentration showed sharp increase because of the water input from the urban sewage plants, illustrating that the controlling mechanism on N2O production varied as pollutant characteristics changed. Stepwise regression analysis showed that CH4 concentrations could be explained by NH4⁺-N concentrations and water temperature, and CH4 concentrations in the surface water of Weihe River was significantly correlated with NH4⁺-N concentrations (R² = 0.70, P < 0.01), suggesting that NH4⁺-N was the key factor in regulating the production and assumption of CH4oxidation in Weihe River in spring. Besides, this study showed that when there was less NO3⁻-N but more NH4⁺-N in river water, CH4and N2O concentrations would be positively correlated, indicating that different nitrogen sources would impact the coupling mechanism of CH4and N2O productions.

[Gas Transfer Velocity of CH4 at Extremely Low Wind Speeds].

Thin boundary theory equation (TBL) is widely used to determine gas fluxes across water-air interfaces, and the gas transfer velocity (k600) is the key environmental factor in the equation. A monthly field campaign was carried out during one year to measure CH4 flux and to probe its exchange rate across the air-water interface in a drinking reservoir and 5 adjacent ponds. The ranges of wind speed and surface water temperature were 0-0.75 m·s-1 and 6.3-30.9℃respectively, and their average values were 0.19 m·s-1 and 19.3℃ respectively. The gas transfer velocity of CH4 varied from 0.20 to 1.99 cm·h-1 with an average of 0.50 cm·h-1. Correlation functions between the gas transfer velocity and the wind speed at 10 m height (U10) and surface water temperature (Tw) were given here to quantify k600. There were significant correlations between the fitted values and actual values both for original and bin-averaged data.

[Partial Pressure of Carbon Dioxide and Methane from Autumn to Winter in Xiangxi Bay of the Three Gorges Reservoir].

The Concentrations of dissolved CH4 and CO2 in Xiangxi Bay of the Three Gorges Reservoir from autumn to winter in 2014 were determined with headspace gas chromatography technology. Then their partial pressures of CH4 and CO2 were calculated according to the Henry's law. Their temporal variation and the effects of environmental parameters were also discussed. The results indicated that the CH4 partial pressure in the surface water ranged 0.64-4.43Pa, with an average of (1.69±0.94)Pa. The CO2 partial pressure varied from 49.90 to 868.91Pa, with the average of (328.48±251.63)Pa. The pCO2 and pCH4 had a strong negative correlation (r=-0.618,P<0.01). During the period of monitoring, the pCO2 and pCH4 in surface water were significantly correlated with pH, DO, chlorophyll a, TP, surface water temperature and water level. Compared with pCH4, pCO2 was more closely correlated with various environmental factors.

[Characteristics of Methane Flux Across the Water-air Interface in Subtropical Shallow Ponds].

Five shallow ponds of Yichang were selected to illustrate the characteristics of methane(CH4) in subtropical eutrophic shallow ponds. CH4 flux across the water-air interface was quantified with static floating chamber method for one year. Annual CH4 fluxes of the five ponds were 4.495, 12.702, 6.827, 8.920, 17.560 mg·(m2·h)-1 respectively. Diffusive CH4 fluxes were 0.075, 0.087, 0.118, 0.086, 0.151 mg·(m2·h)-1 respectively and bubble emissions were 4.420, 12.616, 6.709, 8.834, 17.409 mg·(m2·h)-1 respectively. Over 98% of total CH4 flux was bubble emission and CH4 flux was apparently higher than other aquatic ecosystems. So the CH4 flux of shallow waters was high and bubble emission was the dominant way. CH4 emission would be largely underestimated if the research only focus on the diffusion discharge and ignore the bubble emission.

[Seasonal dynamics of soil organic carbon and active organic carbon fractions in Calamagrostis angustifolia wetlands topsoil under different water conditions].

The experiment was carried in Sanjiang Plain in the northeast of China during the growing season in 2009. Soil organic carbon (SOC), as well as the soil active organic carbon fractions in the 0-20 cm soil layer of Calamagrostis angustifolia wetland under different water conditions were on monthly observation. Based on the research and indoor analysis, the seasonal dynamics of light fractions of soil organic carbon (LFOC) and microbial biomass carbon (MBC) were analyzed. The results indicated that the SOC contents had significantly seasonal dynamics, and the hydrological circle had apparently driving effect on LFOC and MBC during the growing season, especially under the seasonal flooded condition. The freeze-thaw process reduced the SOC, LFOC, MBC contents, with the decreases of 74.53%, 80.93%, 83.09%, while both carbon contents of light and heavy fractions were reduced at the same time. The result also showed that the seasonal flooding condition increased the proportion of LFOC in topsoil, which was larger in marsh meadow (13.58%) than in wet meadow (11.96%), whilst the MBC in marsh meadow (1 397.21 mg x kg(-1)) was less than the latter (1 603.65 mg x kg(-1)), proving that the inundated environment inhibited the mineralization and decomposition of organic matter. But the microbial activity could be adaptive to the flooding condition. During the growing season the MBC soared to 1 829.21 mg x kg(-1) from 337.56 mg x kg(-1) in July, and the microbial quotient was 1.51 times higher than that in June, indicating the high microbial efficacy of soil organic matter. Meanwhile, there was a significant correlation between the contents of LFOC and SOC (r = 0.816), suggesting that higher LFOC content was favorable to the soil carbon accumulation. Moreover, in the seasonal flooded Calamagrostis angustifolia wetland the soil LFOC content was significantly correlated with MBC (r = 0.95), implying that the available carbon source had more severe restriction on the microbial activity under the flooding environment.

[Influence of water level gradient on marsh soil microbial activity of Calamagrostis angustifolia].

Plant aboveground biomass, total organic carbon( TOC), microbial biomass carbon( MBC), basal respiration( BR), microbial quotient (Cmic/Corg) and metabolic quotient (qCO2) in 0-15 cm and 15-50 cm marsh soil of Calamagrostis angustifolia under different water levels were investigated with controlled experiment. The result showed that water level exerted significant effect on plant biomass, which was the highest under 10 cm waterlogged level and of higher productivity under 0-20 cm waterlogged level. TOC, MBC, BR, Cmic/Corg and qCO2 differed significantly under different water levels. BR and TOC responded to different waterlogged levels in the same way. BR and TOC of 0-15 cm marsh soil were the highest under 0 cm waterlogged level, however, BR and TOC of 15-50 cm marsh soil decreased respectively with increasing water, which was corresponding with soil MBC and Cmic/Corg and qCO2 increased with increasing water. As a result, microbial community is altered and microbial activity is decreasing by increasing waterlogged level, and microbial activity is the lowest under 30 cm waterlogged level, which affects organic carbon accumulation and decomposition.

[Exogenous nitrogen enrichment impact on the carbon mineralization and DOC of the freshwater marsh soil].

By laboratory incubation experiment, under aerobic and submerged soil moisture conditions, we investigated the mineralization of soil organic carbon (SOC) and contents of dissolved organic carbon (DOC) with different nitrogen inputs in a freshwater marsh soil. The results showed that under aerobic condition, there were no significant effects on the mineralization of SOC and contents of DOC as the net nitrogen input was 1 mg x g(-1) (N1), however, they were significantly higher than control and N1 treatments when nitrogen input increased to 2 and 5 mg x g(-1) (N2, N3), and the amount of DOC was respectively 187.22% and 203.25% higher than control (250.62 mg x kg(-1)). Under submerged condition, all N treatments restrained the mineralization of SOC, and the content of DOC was respectively 88.34% (N1), 82.69% (N2) and 80.04% (N3) lower than control (642.52 mg x kg(-1)). There were significant positive correlations between the contents of DOC and the amounts of cumulative C by mineralization (R2 was 0.939 and 0.843, respectively), which suggested that the changes of DOC affected by N input might be one of the important reasons that arose the differences of SOC mineralization. The results also indicate that as the waterlogged environment disappeared in wetland, the supply of exogenous nitrogen might bring large loss of SOC through enhancing the mineralization of SOC and leaching of DOC.