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Ancient lead-glazed ceramics frequently corrode physically, chemically, and biologically when buried in soil, submerged in water, or exposed to air. In comparison to the other two environments, relatively little research has been conducted on how lead-glazed ceramics deteriorate in the water environment. Four lead-glazed ceramic samples from the Yangtze Estuary II were examined for their micromorphology and structural composition using scanning electron microscopy-energy spectrum analysis, micro-area X-ray diffraction analysis, fluorescence microanalysis, and Fourier infrared spectroscopy analysis. The results demonstrate the formation of deposits of PbCO3, Pb(OH)Cl, and CuFeS2and corrosion pits and fractures on the glaze layer surfaces. According to the corrosion phenomenon, the lead glaze layers of ceramics mainly underwent chemical and microbial corrosion in water, and the corrosion process of the lead glaze was expounded and modeled. The research results deepen the understanding of the corrosion mechanism of lead-glazed ceramics, which is of great significance for the study of the conservation of lead-glazed ceramics and other types of ceramic relics and can also provide a reference for the long-term preservation of contemporary silicate products.

The utilization of nanotechnology to effectively extract oil and gas resources has garnered attention in response to the growing energy demand. This paper provides a comprehensive overview of several applications of nanotechnology in the oil and gas industry. These applications mostly involve the investigation of how nanoparticles flow through porous materials, the development of nanosensors, and the utilization of nanoparticles to enhance the effectiveness of drilling fluids and increase oil recovery. Nanotechnology is employed to investigate the transport mechanisms of hydrocarbons in nanoporous media and nanoparticles in porous media. This has emerged as a crucial method for assessing hydrocarbon resources. Nanoparticles (NPs) are employed to create temperature and magnetic sensors, as well as imaging techniques, for precise detection of reservoir characteristics and downhole conditions. Nanotechnology has proven to be highly effective in the field of drilling, showcasing its extensive range of possibilities. The addition of NPs improves the rheological properties of drilling fluids, ensures safe drilling, reduces fluid losses, seals nanopores and inhibits shale hydration, and stabilizes the wellbore. Drilling fluids containing NPs are particularly well-suited for situations with high pressure and high temperature. NPs can enhance the effectiveness of fracking fluids by improving their cleanliness, stability, and resistance to friction. Whether hot or cold, NPs show great potential for enhanced oil recovery in thermal and non-thermal chemical flooding. In conclusion, nanotechnology improves the efficiency of exploration, production as well as storage and transportation of oil and gas resources. This study aims to provide academics with a thorough comprehension of the most recent implementations of nanomaterials in the oil and gas industry, while also examining the obstacles and prospects for the future.

ABSTRACTObjective: To determine the underlying mechanism of miR-34b/c in regulating doxorubicin (Dox)-induced myocardial cell injury.Methods: The viability of mouse myocardial cells HL-1 was detected by MTT assay. The apoptosis of HL-1 cells was detected by TUNEL assay. mRNA expressions of ITCH, TNF-α and IL-6 were measured by qRT-PCR. Protein levels of ITCH, NF-κB, TNF-α and IL-6 were measured by western blot. Dual luciferase assay was performed to detect the regulation of miR-34b/c on ITCH. Mouse model of cardiomyopathy was induced by intraperitoneal injection of Dox.Results: Dox reduced HL-1 cell viability and activated NF-κB pathway in HL-1 cells. miR-34b/c expressions were gradually up-regulated and ITCH expression was gradually down-regulated in Dox-treated HL-1 cells. miR-34b/c expression had negative correlation with the mRNA expression of ITCH. Besides, ITCH was a target of miR-34b/c. miR-34b/c mimic reduced cell viability, suppressed ITCH expression, increased TNF-α and IL-6 level, and promoted NF-κB expression in nucleus and cytoplasm of HL-1 cells. Whereas silencing miR-34 protected HL-1 cells through regulating ITCH. Finally, we demonstrated miR-34 antagomir-protected myocardial cells in mouse model of cardiomyopathy.Conclusion: miR-34b/c decreased HL-1 cell viability and promoted the secretion of proinflammatory cytokines in Dox-induced myocardial cells through ITCH/NF-κB pathway.

Background: Acupuncture has been recommended as an alternative therapy for migraine. Emerging evidence suggests that the 5-HT7receptor (5-HT7R) plays a significant facilitatory role in descending modulation in migraine pathophysiology, and that activation of 5-HT7R in the descending pathway is involved in migraine central sensitisation.Objective: To investigate the ability of electroacupuncture (EA) to ameliorate central sensitisation via modulation of 5-HT7R in the descending pain pathways using a rat model of migraine induced by repetitive dural electrical stimulation (DES).Design: 64 male Sprague-Dawley rats were randomly divided into four groups: Normal group; DES group (receiving dural electrical stimulation only); DES+GB20 group (DES model group treated with EA at GB20); and DES+Sham group (DES model group treated with EA at a non-traditional (sham) acupuncture point). The presence of cutaneous allodynia was determined by measuring facial and hind-paw withdrawal latencies to electronic von-Frey. The expression of 5-HT7R in the descending pathways (periaqueductal grey, raphe magnus nucleus, and trigeminal nucleus caudalis) was assessed using immunofluorescence and Western blotting.Results: Facial and hind-paw withdrawal thresholds were significantly increased in the DES+GB20 group compared with the untreated DES group. The expression of 5-HT7R was significantly decreased in the DES+GB20 group compared with the DES group (one-way analysis of variance (ANOVA), P<0.05). No significant differences in behaviour or expression were found between the rats in the DES+Sham group and the untreated DES group (one-way ANOVA, P>0.05).Conclusion: EA at GB20 may ameliorate central sensitisation in migraine by inhibiting the activation of 5-HT7receptors in the descending pain pathway in a rat model of migraine.

With the increase of the scale of animal husbandry, the negative effect of nitrogen and phosphorus, antibiotics, heavy metals and other pollutants in livestock wastewater has been increasing. Natural adsorption materials are a new type of environmental protection materials that have attracted attention in recent years. Many researchers have developed natural adsorption materials using microorganisms, algae, animal and plant derivatives and industrial and agricultural wastes. However, there has been no systematic review regarding the natural adsorbents for the purpose to treat the livestock wastewater. In this paper, the pollutants and their hazards in livestock wastewater were reviewed. The characteristics of such pollutants were introduced in detail, and the research progress of natural adsorbent materials and their effect on livestock wastewater treatment was summarized. This review is intended to provide ideas and references for the development and application of natural adsorbent.

Underwater pottery relics salvaged from shipwrecks are vulnerable to physical, chemical and biological corrosion. In this study, the microscopic morphology and structural composition of glazed pottery fragments excavated from the South China Sea as well as purple clay teapot samples from the Yangtze River Estuary II shipwreck were analyzed by means of optical microscopy, scanning electron microscope equipped with energy dispersive spectrometer, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier infrared transform spectroscopy and photoluminescence spectroscopy. According to the research results, the corrosion products deposited on the surface of the glazed pottery fragment from the South China Sea mainly included FeOOH and MnO2, whereas those on the surface of the purple clay teapot fragment from the Yangtze River Estuary II shipwreck primarily incorporated FeS2and FeS. According to the corrosion phenomenon, it was speculated that the underwater pottery relics were mainly corroded by different microorganisms in the underwater environment, including manganese-oxidizing bacteria, dissimilatory metal-reducing bacteria and sulfate-reducing bacteria. As the corrosion process of these cultural artifacts was described and related models were established, this study provides valuable reference for the disease removal and protection of pottery relics.

The ‘Yangtze River Estuary No. 2’ shipwreck of the Qing Dynasty (1636–1912 CE) is one of the most well-preserved ancient wooden shipwrecks discovered underwater in China to date. Unfortunately, most green lead-glazed cups salvaged out of the shipwreck have severely degraded and generally blackened in the underwater environment. In this study, the degradation mechanism of the lead glaze in the underwater environment were investigated in depth. It was found that the degradation of lead glaze involved several complex chemical and physical processes. The special environmental conditions caused by the corrosion of iron components in the shipwrecks may be an important reason for the loss of Si elements in corrosion layers. The appearance changes of the green glaze are related to the leaching of Cu2+ions and the gradual transformation to a lead-rich corrosion layer. The iridescent phenomenon may be related to the thin-film interference of the laminated corrosion layers.

This study aimed to validate the fully automated Pangao PG-800B68 upper-arm device according to the European Society of Hypertension International Protocol (ESH-IP) revision 2010.

Obstructive sleep apnea (OSA) is an emerging risk factor for cardiovascular disease. Microcirculatory dysfunction has been proposed as a potential mechanism in the pathogenesis of cardiovascular disease in OSA. This study aims to investigate the relationship between OSA and coronary microcirculatory function.

Survival of children with chronic medical illnesses is leading to an increase in secondary osteoporosis due to impaired peak bone mass (PBM). Insulin-like growth factor type 1 (IGF-1) levels correlate with the pattern of bone mass accrual and many chronic illnesses are associated with low IGF-1 levels. Reduced serum levels of IGF-1 minimally affect the integrity of the skeleton, whereas recent studies suggest that skeletal IGF-I regulates PBM. To determine the role of IGF-1 in postnatal bone mass accrual regardless of source, we established an inducible type 1 Igf receptor Cre/lox knockout mouse model, in which the type 1 Igf receptor was deleted inducibely in the mesenchymal stem cells (MSCs) from 3–7 weeks of age. The size of the mouse was not affected as knockout and wild type mice had similar body weights and nasoanal and femoral lengths. However, bone volume and trabecular bone thickness were decreased in the secondary spongiosa of female knockout mice relative to wild type controls, indicating that IGF-1 is critical for bone mass. IGF-1 signaling in MSCs in vitro has been implicated to be involved in both migration to the bone surface and differentiation into bone forming osteoblasts. To clarify the exact role of IGF-1 in bone, we found by immunohistochemical analysis that a similar number of Osterix–positive osteoprogenitors were on the bone perimeter, indicating migration of MSCs was not affected. Most importantly, 56% fewer osteocalcin-positive mature osteoblasts were present on the bone perimeter in the secondary spongiosa in knockout mice versus wild type littermates. These in vivo data demonstrate that the primary role of skeletal IGF-1 is for the terminal differentiation of osteoprogenitors, but refute the role of IGF-1 in MSC migration in vivo. Additionally, these findings confirm that impaired IGF-1 signaling in bone MSCs is sufficient to impair bone mass acquisition.

To enhance the exhaust efficiency during ventilation, three types of air duct outlets were imported. According to the characteristics of velocity distribution simulated by numerical method, the flow field is divided into the mixing zone and the exhaust zone. The gradual contracted air duct outlet can enhance the mixing effect between fresh air and smoke. In the exhaust zone, however, the flow velocity on the upper section of the tunnel is weakened, which is unfavorable for smoke exhaust. Gradual expanded air duct outlet, on the contrary, may weaken the concentration effect of the airflow. The flow velocity on the upper section of the tunnel is increased in the exhaust zone, thus the flow field is more homogenized, which is in favor of smoke exhaust.

To investigate the protective effects and the possible molecular mechanisms of chlorogenic acid on H2O2-induced dysfunction and apoptosis in human umbilical vein endothelial cells (HUVECs). HUVECs were divided into three groups: H2O2 groups (0, 5, 10, 20, 50mM), chlorogenic acid (100nmol/L) groups and atorvastatin (10μmol/L) groups. The eNOS mRNA expression was measured by RT-PCR. The content of NO in the supernatant was detected by the nitrate reductase assay. Cells activity was evaluated by the MTT assay. The level of reactive oxygen species (ROS) in cells was measured using H2DCF-DA as a fluorescence probe. Results demonstrated that H2O2 caused a significant down-regulation of eNOS mRNA expression and decreased the secretion of NO in a dose-dependent manner compared with the control group. Furthermore, H2O2 induced cell apoptosis, increased ROS accumulation. Nevertheless, these effects of H2O2 could be blocked by chlorogenic acid in chlorogenic acid pretreatment groups. CONCLUSION:chlorogenic acid can inhibite H2O2-induced dysfunction and apoptosis in HUVECs, which may be related to its effects on suppressing oxidative stress, up-regulating eNOS pathway. These results suggest the usefulness of chlorogenic acid particularly in the treatment of cardiovascular disease.

Background Myeloperoxidase (MPO) has been associated with the development of atrial fibrillation (AF), but its impact on the recurrence of AF after catheter ablation has not been explored. This study investigated the effect of plasma MPO on recurrence after catheter ablation of paroxysmal AF.Methods and Results Two hundred eighty-eight consecutive patients with paroxysmal AF and who underwent circumferential pulmonary vein isolation were prospectively enrolled. After a mean ± SD follow-up of 516 ± 204 (91–910) days, the recurrence rates were 16.9%, 25.7%, 29.7%, and 38.0% from the lowest MPO quartile to the highest MPO quartile, respectively (P= 0.023). After adjustment for age, sex, left atrial diameter, high-sensitivity C-reactive protein, and pulmonary vein isolation, there was an increased risk of recurrence in the subjects with the highest MPO quartile compared with those with the lowest quartile (hazard ratio, 3.18; 95% confidence interval, 2.12–5.23; P= 0.024). As a continuous variable, MPO was also an independent predictor of recurrence (hazard ratio, 2.12; 95% confidence interval, 1.71–3.27; P= 0.032).Conclusions Patients with high MPO levels were at an increased risk of AF recurrence after catheter ablation.

The morphotropic phase boundary (MPB) in lead-free ferroelectrics, starting from a quadruple point (QP), often displays large piezoelectric responses due to the flattened free-energy profiles. In this work, we found that the QP composition rendering most flattened energy profiles could also exhibit abnormally low piezoelectric constants in Hf-doped BaTiO3. Such an anomaly in the strength of piezoelectricity can be ascribed to the progressive influence of additional strain heterogeneity induced by the substitution of Hf4+for Ti4+in BaTiO3, which was overlooked previously. An intermediate level of strain heterogeneity can form an invisible ferroelectric crossover consisting of both micro- and nanodomains, resulting in a large elastic softening and high piezoelectricity. With a further increase in the level of strain heterogeneity, the extinction of regular ferroelectric domain structures and pinned polar dynamics resulted in the feeble piezoelectric outputs near the QP composition. Impressively, a giant d33of ∼610 pC/N has been accordingly obtained through employing a ferroelectric crossover at off-QP composition in Zr-doped BaTiO3, further underpinning the critical role of uncovered ferroelectric crossover on piezoelectricity along MPB. This work offers another degree of freedom in the design of high-performance eco-friendly piezoelectric ceramics.

In 1964, a debate that attracted widespread attention occurred within Chinese philosophical circles on the question of "one divides into two" and "two combine into one." But because the scholarly questions became mixed with politics, this debate never fully developed, and the critique of "one divides into two" was hurriedly terminated. "One divides into two" was judged to be the "correct, living, and common expression of the true nature and core of the materialist dialectic — the theory of the unity of opposites," and it was interpreted as representing the broad functions of the revolutionary dialectic.