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To optimize and improve the impact performance of a hydraulic rock drill, it is helpful to test the stress waves of the drill and analyze the impact energy, impact frequency, and energy utilization rate. For this study, a stress wave test bench was designed and built, according to international standards, in order to study the impact process of a hydraulic rock drill under the working pressures of 18 MPa and 23 MPa. The impact energy, impact frequency, and energy utilization rate of two different hydraulic rock drill pistons in low, middle, and high gear were analyzed using a control variable method. The results demonstrate that the impact stress waves of the rock drill periodically occur in the drill rod, and then decay exponentially until they become close to zero. Moreover, the amplitude of the incident stress wave determines the rock-breaking ability of the drill. The impact energy of the short piston is greater than that of the long piston, with a maximum average value of 346.1 J; the impact frequency of the long piston is higher than that of the short piston, with a maximum average value of 62 Hz; and the energy utilization rate of the short piston is higher than that of the long piston, with a maximum average value of 56.92%, which is close to the theoretical ideal efficiency. Therefore, it can be concluded that the impact performance of a hydraulic rock drill can be effectively tested using the proposed horizontal bench, and that piston characteristics and the working pressure are the main factors affecting impact performance. Accordingly, when developing a hydraulic rock drill, it is advisable to select a shorter piston and a higher working pressure, thus allowing the drill to provide good impact performance. [ABSTRACT FROM AUTHOR]

Purpose: The PACIFIC study has demonstrated that the administration of durvalumab following concurrent chemoradiotherapy can significantly improve both overall survival and progression-free survival rates in patients with locally advanced unresectable non-small cell lung cancer. While the latest NCCN guidelines recommend this combination regimen, they do not specify the optimal timing for administering durvalumab after completing radiotherapy. The PACIFIC study suggested initiating durvalumab within 42 days of completing radiotherapy, but early administration of the drug may increase the incidence of pneumonitis. Therefore, we conducted this study to investigate whether the time interval between completion of radiotherapy and initiation of durvalumab treatment is associated with the risk of pneumonitis (Grade ≥ 3), which is the primary endpoint, as well as progression-free survival, which is the secondary endpoint. Methods: A comprehensive search of clinical trials in PubMed and EMBASE was conducted up to March 2023 to identify clinical trials involving locally advanced unresectable non-small cell lung cancer patients who were treated with durvalumab following chemoradiotherapy. Meta-analysis was performed on single-arm studies to estimate the incidence of pneumonitis (Grade ≥ 3) and progression-free survival in all studies, as well as in studies that administered durvalumab within 42 days after completion of radiotherapy. Results: This meta-analysis consisted of nine studies with a total of 2560 patients. The analysis showed that the incidence of pneumonitis (Grade ≥ 3) was 5.36% [95%CI (0.03, 0.08), I2 = 18.41%, p = 0.29], while the 1-year progression-free survival rate was 57.91% [95%CI (0.53, 0.63), I2 = 10.57%, p = 0.35]. Furthermore, when the duration between completion of radiotherapy and initiation of durvalumab treatment was shorter than 42 days, the incidence of pneumonitis (Grade ≥ 3) was 4.12% [95%CI (0.02, 0.06), I2 = 0.00%, p = 0.56], with a 1-year progression-free survival rate of 61.03% [95%CI (0.51, 0.71), I2 = 59.06%, p = 0.09]. Conclusion: Overall, based on the available evidence, it appears that there is no significant increase in pneumonitis or decrease in progression-free survival (PFS) when the time interval is less than 42 days and a shorter interval between treatment sessions does not necessarily have a detrimental effect on the rate of pneumonitis. We recommend that clinicians carefully evaluate the specific circumstances of each patient to determine the optimal timing for initiating immunotherapy. [ABSTRACT FROM AUTHOR]

With the gradual depletion of fossil energy sources and the improvement in environmental protection attention, efficient use of energy and reduction in carbon emissions have become urgent issues. The integrated electricity and heating energy system (IEHS) is a significant solution to reduce the proportion of fossil fuel and carbon emissions. In this paper, a stochastic optimization model of the IEHS considering the uncertainty of wind power (WP) output and carbon capture power plants (CCPs) is proposed. The WP output in the IEHS is represented by stochastic scenarios, and the scenarios are reduced by fast scenario reduction to obtain typical scenarios. Then, the conventional thermal power plants are modified with CCPs, and the CCPs are equipped with flue gas bypass systems and solution storage to form the integrated and flexible operation mode of CCPs. Furthermore, based on the different load demand responses (DRs) in the IEHS, the optimization model of the IEHS with a CCP is constructed. Finally, the results show that with the proposed optimization model and shunt-type CCP, the integrated operation approach allows for a better reduction in carbon capture costs and carbon emissions. [ABSTRACT FROM AUTHOR]

Presently, more than half of cancer patients receive radiotherapy to cure localized cancer, palliate symptoms, or control the progression of cancer. However, radioresistance and radiation-induced bystander effects (RIBEs) are still challenging problems in cancer treatment. Exosomes, as a kind of extracellular vesicle, have a significant function in mediating and regulating intercellular signaling pathways. An increasing number of studies have shown that radiotherapy can increase exosome secretion and alter exosome cargo. Furthermore, radiation-induced exosomes are involved in the mechanism of radioresistance and RIBEs. Therefore, exosomes hold great promise for clinical application in radiotherapy. In this review, we not only focus on the influence of radiation on exosome biogenesis, secretion and cargoes but also on the mechanism of radiation-induced exosomes in radioresistance and RIBEs, which may expand our insight into the cooperative function of exosomes in radiotherapy. 5Br1qo9hcMg24ERPyrtzPU Video abstract [ABSTRACT FROM AUTHOR]

Policy document mention is considered to indicate the significance and societal impact of scientific product. However, the accuracy of policy document altmetrics data needs to be evaluated to fully understand its strength and limitation. An in-depth coding analysis was conducted on sample policy documents records of Altmetric.com database. The sample consists of 2079 records from all 79 distinct policy document source platforms tracked by the database. Errors about mentioned publications in the policy documents (type A error) are found in 8% of the records, while errors about either the recorded policy documents or the mentioned publications in the altmetrics database (type B error) are found in 70% of the records. In type B error, policy document link error (5% of the records) could be attributable to the policy document website, transcription error (52% of the records) could be attributable to the third-party bibliographic data provider. These two categories of error are relatively minor and may have limited influence on altmetrics research and practices. False positive policy document mention (13% of the records), however, could be attributable to the Altmetric database and may diminish the validity of research based on the policy document altmetrics data. The underlying reasons remain to be further investigated. Considering the high complexity of extracting mentions of publications from various sources and formats of policy documents as well as its short history, Altmetric database has achieved excellent performance. [ABSTRACT FROM AUTHOR]

The enhancement of the breakdown power during the spark discharge process has been proved to be beneficial for the flame kernel formation process under lean/diluted conditions. Such a strategy is realized by using a conventional transistor coil ignition system with an add-on capacitance in parallel to the spark plug gap in this paper. In practical application, the use of different ceramic material other than aluminum oxide can change the parasitic capacitance of the spark plug, achieving similar effect in terms of rescheduling the discharge energy released during the breakdown phase. Detailed research has been carried out to investigate the effect of the parallel capacitance and the cross flow velocity on the flame kernel formation and propagation process. With the increase in parallel capacitance, more spark energy is delivered during the breakdown phase, while less energy is released during the arc/glow phase. Shadowgraph images of the spark plasma reveal that the high-power spark discharge can generate a larger high-temperature area with enhanced electrically prompted turbulence under quiescent conditions, as compared with that using the conventional transistor coil ignition discharge strategy under the same condition. The breakdown enhanced turbulence of the high-power spark is proved to be beneficial for the flame kernel development, especially with the lean or exhaust gas recirculation diluted combustible mixtures, given that sufficient spark energy is available for the high-power spark strategy to successfully generate the breakdown event. The results of combustion tests under flow conditions reveal that the breakdown enhanced turbulence of the high-power spark tends to be overshadowed by the turbulence generated from the flow field, and both the increase in flow velocity and parallel capacitance contribute to the reduction in discharge duration of the arc/glow phase. Therefore, the benefits brought about by the high-power spark discharge tend to diminish with the intensification of flow velocity. [ABSTRACT FROM AUTHOR]

Bone metastasis caused by breast cancer leads to significant complications in treatment, and the resulting osteolysis considerably affects patients' overall survival and quality of life. Gö6983 is a broad spectrum protein kinase C inhibitor. In this study, based on our finding that the Gö6983 inhibits osteolysis, we applied Gö6983 to the MDA‐MB‐231 breast cancer‐induced mouse bone metastasis model. And we found that Gö6983 has a strong inhibitory effect on the tumorigenic model of breast cancer by promoting the mitochondrial apoptosis pathway. Our study, therefore, demonstrates that Gö6983 has a potential inhibitory effect on breast cancer‐induced osteoclast activation and provides mechanistic insight that may prove useful for designing future treatments. [ABSTRACT FROM AUTHOR]

Spark discharge under flow conditions in different gas media is compared. The gases include nitrogen, pure methane, and methane–air mixtures with different volume ratios. The self-illuminated spark plasma photos, and the discharge current and voltage waveforms are recorded. [ABSTRACT FROM AUTHOR]

Chelating 1,2,3-triazole-4-carboxylic acids were successfully introduced onto the cross-linked PGMA microsphere surfaces by the combination of ring-opening reactions and the click chemistry process between the alkynyl groups of propiolic acid (PA) and the epoxy groups on the surfaces of the PGMA microspheres. The resultant PA-conjugated PGMA microspheres were found to be an effective adsorbent for Pb(ii) removal from aqueous solutions. Success in each functionalization step was ascertained by ATR-FTIR, XPS and SEM characterization. Batch and column adsorption experiments were performed to determine the adsorption kinetics, adsorption isotherms and thermodynamics of Pb(ii) ions on the as-synthesized microspheres. The Langmuir-fitted maximum adsorption capacity for Pb(ii) ions was found to be 69.41 mg g−1 at a solution pH of 5.0, together with the adsorption equilibrium being achieved within 60 min. The thermodynamic studies demonstrated an endothermic and spontaneous adsorption process of Pb(ii) ions on the PA-conjugated PGMA microspheres. Column adsorption studies revealed the decrease in the adsorption capacities of the breakthrough and exhaustion points with increasing flow rate. The postulated adsorption mechanism was attributed to the electrostatic interactions from carboxylic groups and chelation or coordination of Pb(ii) ions from the triazole moieties, which was facilitated to form a pluralistic potential trap for Pb(ii) ions, as confirmed by XPS characterization. [ABSTRACT FROM AUTHOR]

Engine tests were conducted to investigate the efficiency and the peak pressure rise rate performance of different fuel injection strategies for the direct injection of neat n-butanol in a compression ignition engine. Three different strategies were tested: a single-shot injection; a pilot injection; a post-injection. A single-shot injection timing sweep revealed that early injections had the highest indicated efficiency while late injections reduced the peak pressure rise rate at the cost of a slightly reduced thermal efficiency. Delayed single-shot injections also had increased emissions of nitrogen oxides, total hydrocarbon and carbon monoxide. Addition of a pilot injection had a negative effect on the peak pressure rise rate. Because of the low cetane number of butanol and the relatively lean and well-premixed air–fuel mixture, the pilot injection failed to autoignite and instead ignited simultaneously with the main injection. This resulted in slightly increased peak pressure rise rates and significantly increased unburned butanol hydrocarbon emissions. Conversely, the use of an early post-injection produced a noticeable engine power output and allowed the main injection to be shortened and the peak pressure rise rate to be substantially reduced. However, relatively early post-injections slightly reduced the indicated efficiency and increased the nitrogen oxide emissions and the carbon monoxide emissions compared with the single-shot injection strategy. These results recommended the use of a single-shot injection for low loads and medium loads owing to a superior thermal efficiency and suggested that the application of a post-injection may be more suited to high-load conditions because of the substantially reduced peak pressure rise rates. [ABSTRACT FROM AUTHOR]

Characterized by its customary symbol system and simple and vivid expression patterns, cyber language acts as not only a tool for convenient communication but also a carrier of abundant emotions and causes high attention in public opinion analysis, internet marketing, service feedback monitoring, and social emergency management. Based on our multidisciplinary research, this paper presents a classification of the emotional symbols in cyber language, analyzes the cognitive characteristics of different symbols, and puts forward a mechanism model to show the dominant neural activities in that process. Through the comparative study of Chinese, English, and Spanish, which are used by the largest population in the world, this paper discusses the expressive patterns of emotions in international cyber languages and proposes an intelligent method for affective computing on cyber language in a unified PAD (Pleasure-Arousal-Dominance) emotional space. [ABSTRACT FROM AUTHOR]

This paper proposed an analytical model on the deterioration of magnetic sensitivity of sectorial split-drain magnetic field-effect transistors (SD-MAGFETs). The deterioration is governed by the trap fill rate at the channel boundary traps, which is geometric dependent. Experimental results are presented which show good consistency with the analytical derivation. The deterioration is the most severe at a sector angle of 54.6^\circ, which shows a design tradeoff with sensing hysteresis. Design guidelines for sectorial SD-MAGFET to obtain high sensitivity hysteresis and slow sensitivity deterioration are also presented which provide important information for efficient design. [ABSTRACT FROM PUBLISHER]

This paper proposed an analytical model on the geometric dependence of the transient sensitivity and transient sensing hysteresis of sectorial split-drain magnetic field-effect transistors (SD-MAGFETs). We also conjectured that the transient sensing hysteresis is caused by the charge trapped on channel boundary, and is also geometric dependent. Experimental results are presented which show good consistence with the analytical derivation. The derived analytical model and experimental results can be used as a design guideline for the optimization and trade-off of the transient sensitivity and transient sensing hysteresis of the sectorial SD-MAGFETs. [ABSTRACT FROM AUTHOR]

The relationships between above-ground stem, branch, leaf masses and stand density index (SDI) were analysed in Populus × euramericana (Dode) Guinier stands in Jiangsu Province, China. The allometric equations developed in this study accurately estimated masses of above-ground and specific above-ground tree components in stands with different SDIs. The relationship between the mean above-ground mass w and the ratio of stem to the above-ground (wS/w) was examined. With increasing w, the stem mass ratio wS/w increased. Mean masses of above-ground and tree components decreased significantly with increasing SDI at age 9 years, indicating the presence of competition-induced limitations to growth. The mean above-ground mass–SDI and mean component mass–SDI were strongly correlated with above-ground mass-SDI and tree component mass–SDI, respectively. An equation describing the relationship between the mean leaf area u and SDI was developed, which fitted well for the u-SDI data. Stem mass increment exponentially increased with increasing leaf area index. [ABSTRACT FROM PUBLISHER]

A belt of khondalite-series rocks in the Western Block of the North China craton (NCC) are considered to represent products of the collision between the north Yinshan and the south Ordos terranes before final amalgamation of the NCC basement. The Jining Complex of Inner Mongolia occurs in the eastern part of the Khondalite Belt and is crosscut by the Trans-North China Orogen. Khondalite rocks of the Jining Complex mainly comprise sillimanite-garnet gneiss, garnet/sillimanite-bearing granite, massive porphyritic granite, garnet quartzite, calc-silicate, and marble with minor felsic gneiss and mafic granulite. LA-ICP-MS, U-Pb dating and cathodoluminescence (CL) image analysis of zircons from five rocks from the complex, i.e. Sil-Bt-Grt leptynite gneiss, Spl-Sil-Ksp-Grt vein in (Crd)-Sil-Grt gneiss, Sil-Grt-K-Fsp mylonite from a shear zone, Crd-bearing Sil-Grt gneiss, and granite were used to determine protolith and metamorphic ages of the khondalite-series rocks. Results of 315 detrital zircon grains indicate five age populations: 2410-2550 Ma, 2162 Ma, 2047-2099 Ma, 1950-1993 Ma, and 1866 Ma. CL investigation reveals that zircon grains of most samples are rounded, unzoned with low Th/U, indicating a metamorphic origin, whereas quite a few grains in some rocks are characterized by magmatic oscillatory zoning and comparatively high Th/U, and are typically overgrown by metamorphic, low CL rims with low Th/U. Three samples of Sil-Bt-Grt gneiss record oldest ages of ∼2550-2480 Ma, suggesting an Archaean/early Palaeoproterozoic provenance for the Jining Complex. Ages of ∼2162-2047 Ma are interpreted as the metamorphic modified inherited source of supercrustal protoliths of the khondalite-series rocks. The khondalite depositional age is defined as 2228-2027 Ma by concordant ages obtained in this research. The Sil-Ksp-Grt vein and the granite have single population ages of 1985 ± 28 Ma and 1957 ± 19 Ma, respectively, and are inferred to record the same metamorphic event, i.e. formation of the Khondalite Belt within the Western Block owing to the collision of the north Yinshan and the south Ordos terranes. The Sil-Grt-K-Fsp mylonite yields a single group age of 1866 ± 22 Ma, which may date final suturing of the Eastern Block and the Western Block and stabilization of the NCC. [ABSTRACT FROM AUTHOR]

Synthetic aperture imaging radiometers (SAIRs) are powerful passive microwave systems for high-resolution imaging by use of synthetic aperture technique. However, the ill-posed inverse problem for SAIRs makes it difficult to reconstruct the high-precision brightness temperature map. The traditional regularization methods add a unique penalty to all the frequency bands of the solution, which may cause the reconstructed result to be too smooth to retain certain features of the original brightness temperature map such as the edge information. In this paper, a multi-parameter regularization method is proposed to reconstruct SAIR brightness temperature distribution. Different from classical single-parameter regularization, the multi-parameter regularization adds multiple different penalties which can exhibit multi-scale characteristics of the original distribution. Multiple regularization parameters are selected by use of the simplified multi-dimensional generalized cross-validation method. The experimental results show that, compared with the conventional total variation, Tikhonov, and band-limited regularization methods, the multi-parameter regularization method can retain more detailed information and better improve the accuracy of the reconstructed brightness temperature distribution, and exhibit superior noise suppression, demonstrating the effectiveness and the robustness of the proposed method. [ABSTRACT FROM AUTHOR]

This article has been retracted. [ABSTRACT FROM AUTHOR]

This article has been retracted. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative disease of the cartilage that is prevalent in the middle-aged and elderly demography. Polydatin (PD), a natural resveratrol glucoside, has shown significant anti-inflammatory and anti-arthritic potential in previous studies. This study was designed to evaluate the therapeutic properties of PD in vitro and in vivo, and elucidate their underlying mechanisms. The expression levels of all relevant factors were evaluated by qRT-PCR, western blotting, and immunohistochemistry (IHC) where suitable. Reactive oxygen species (ROS) and apoptosis were analyzed using the suitable probes and flow cytometry. The histological evidence of cartilage was assessed in rat models, moreover, the several serum cytokines levels and autophagy levels were evaluated. The result showed PD displayed significant chondro-protective effects, inferred in terms of reduced inflammation and cartilage degradation, apoptosis inhibition, and lower ROS production. The protective effects were attenuated by the autophagy inhibitor 3-MA, indicating a mediating role of autophagy in PD action. Mechanistically, PD exerted its effects by inhibiting the MAPK and PI3K/Akt signaling pathways which led to the down-regulation of mTOR. In conclusion, PD protects against cartilage degeneration by activating the autophagy flux in the chondrocytes via the MAPK and PI3K/Akt signaling pathways. [ABSTRACT FROM AUTHOR]