Search

Inclined pile foundations are commonly adopted in the support of wharf, harbor, bridge, and wind turbine structures. In the context of offshore wind turbines, inclined piles are typically arranged symmetrically around a circle with an elevated pile cap above sea level, referred to as an elevated pile-cap foundation. However, limited research exists on the impedances of inclined pile foundations with elevated pile caps. In this study, a theoretical model was developed that incorporates a homogeneous soil half-space and an inclined pile foundation with an elevated pile cap. The pile and soil half-space were modeled as Euler-Bernoulli beams and linear-elastic continuum, respectively. The soil's contribution to the pile's dynamics was represented by the receptance matrix, established at discrete interactions points along the pile's embedded section. The effects of the rake angle and scour depth on the dynamic impedances of the inclined pile foundation with an elevated pile cap were investigated. It was observed that the peak frequency of impedance shifts to a lower value as the scour depth increases; whereas the peak frequency shifting effect is less prominent when the rake angle changes. The impedance of the elevated pile-cap foundation is more sensitive to the pile's rake angle compared to the scour depth. [ABSTRACT FROM AUTHOR]

In offshore engineering, marine clays, which are widespread in the southeastern coastal areas of China, may be subjected to two-way cyclic stresses. To experimentally investigate the effects of the two-way cyclic stress with low-stress amplitude on the cyclic behavior of soft marine clay, a series of triaxial tests is performed on intact marine clay from Zhoushan covering various values of the cyclic stress ratio (CSR) and confining pressure (p′0). Several useful conclusions are inferred: First, the double-amplitude axial strain (εDA), dynamic axial modulus (E), and energy dissipation (W) increase with the CSR. Second, under the same CSR, the value of εDA is independent of p′0. The values of E and W increase with increasing p′0 during cyclic loadings, whereas the normalized modulus and normalized energy are independent of p′0. Third, an allowable CSR is proposed based on the strain behavior and energy concept. Based on the experimental results, two equations are established to predict the dynamic axial modulus and double-amplitude axial strain. [ABSTRACT FROM AUTHOR]

Background: Studies have reported that blood transfusion may have an association with survival outcomes of cancer patients. This study was aimed at finding the effect of intra-operative blood transfusion on the prognosis of patients of hepatocellular carcinoma (HCC). Methods: This was a retrospective study. HCC patients who underwent tumor resection from January 2013 to November 2018 at Harbin Medical University Cancer Hospital were included. The survival time of patients receiving or not receiving blood transfusion during the operation were compared. Results: Of HCC patients, 21.1% (102/484) received intra-operative blood transfusion. After propensity score matching, 87 pairs of patients were included in the study. In the subset of patients with a tumor size of > 4 cm, univariable analysis found that there were significant differences in recurrence-free survival (RFS; P=0.004) and overall survival (OS; P=0.028) between blood transfusion and non-blood transfusion groups. After multivariable Cox regression analysis, intra-operative blood transfusion was an independent risk factor for RFS (HR: 2.011, 95% CI: 1.146– 3.529, P=0.015), but not for OS (HR: 1.862, 95% CI: 0.933– 3.715, P=0.078) in the subset of patients with a tumor size of > 4 cm. Conclusion: Intra-operative blood transfusion was associated with worse RFS in HCC patients with a tumor size of > 4 cm. [ABSTRACT FROM AUTHOR]

Influence of the depth and location of perforation, direction and magnitudes of in situ stresses, wellbore angle, and pumping pressure is investigated numerically for the hydraulic fracture. 3D models of rock formation with vertical, inclined or horizontal wells containing semi‐circular crack are analyzed to obtain both KI and the minimum pumping pressure. By computing the magnitude and sign of the T‐stress it is demonstrated that hydraulic fracture path is generally stable except for a very limited situations in which the vertical well is subjected to the lowest in situ stresses. The minimum horizontal in situ stress has the most dominant role in controlling the hydraulic fracture. A direct relationship between KI and T was obtained for different ranges of in situ stresses and some relations were presented for estimating the critical stress intensity factor at the onset of hydraulic fracture and minimum injection pressure in terms of the applied in situ stresses. Highlights: Influence of in situ stresses, well orientation and perforation size on KI and T values.Determining the minimum pumping pressure in terms of in situ stresses and well type.Stability analysis of hydraulic fracture path for vertical‐oblique‐horizontal wellbores.Obtaining direct relationships between KI and T by changing in situ stresses. [ABSTRACT FROM AUTHOR]

The dynamic parameters of a dangerous rock mass reflect the degree of damage of the structure of its surface. There is still an urgent problem to identify the dynamic parameters of a dangerous rock mass based on the characteristics of the constant micromotion at its site. To address this problem, a method is proposed to identify the dynamic characteristics of a dangerous rock mass undergoing excitation caused by constant micromotion: (1) the vibration of a dangerous rock mass undergoing excitation from constant micromotion is classified as forced undamped structural vibration with a single degree of freedom. The ratio of the amplitude of the spectrum of the dangerous rock mass to the amplitude of the spectrum of the bedrock is defined as the relative amplitude spectrum. The first-order natural frequency is identified from the relative amplitude spectrum. (2) Bedrock is the source of excitation of a dangerous rock mass. When a mechanical wave propagates to a dangerous rock mass, it crosses the porous surface of media with structural damage, and mechanical wave scattering occurs. The frequency domain of the mechanical wave changes. The center frequency shifts to a low frequency. By means of laboratory model tests, the changes in the dynamic parameters of models of a cantilevered dangerous rock mass and a sliding dangerous rock mass with structural surface damage are analyzed. It is concluded that (1) based on the theory of vibration mechanics, the first-order natural frequencies of dangerous rock masses can be obtained from their relative amplitude spectra. The first-order natural frequencies of dangerous rock masses undergoing constant micromotion are measurable. (2) The damage of the structural surface of a dangerous rock mass with macroscopic fractures can be identified by its first-order natural frequency. The center frequency cannot reflect the development of fractures. The damage of the structure of the surface of a dangerous rock mass with microscopic fractures can be identified by the change in the center frequency in its high-frequency band. The first-order natural frequency cannot reflect the development of fractures. (3) There are limitations in using single vibration mechanics theory or elastic wave scattering theory to analyze the damage of the structure of the surface of a dangerous rock mass; it is more effective to integrate both methods. [ABSTRACT FROM AUTHOR]

Disasters caused by landslides pose a considerable threat to people's lives and property, resulting in substantial losses each year. Landslide displacement rate prediction (LDRP) provides a useful fundamental tool for mitigating landslide disasters. However, more accurately predicting LDRP remains a challenge in the study of landslides. Lately, ensemble deep learning algorithms have shown promise in delivering a more precise and effective spatial modeling solution. The core aims of this research are to explore and evaluate the prediction capability of three progressive evolutionary deep learning (DL) techniques, i.e., a recurrent neural network (RNN), long short-term memory (LSTM), and a gated recurrent unit (GRU) ensemble AdaBoost algorithm for modeling rainfall-induced and reservoir-induced landslides in the Baihetan reservoir area in China. The outcomes show that the ensemble DL model could predict the Wangjiashan landslide in the Baihetan reservoir area with improved accuracy. The highest accuracy was achieved in the testing set when the window length equaled 30. However, assembling two predictors outperformed the accuracy of assembling three predictors, with the mean absolute error and root mean square error reaching 1.019 and 1.300, respectively. These findings suggest that the combination of strong learners and DL can yield satisfactory prediction results. [ABSTRACT FROM AUTHOR]

Background: Pregabalin is commonly used to relieve neuropathic pain. However, data are lacking on its efficacy for the treatment of chronic cancer pain. The purpose of this study was to determine the analgesic efficacy of pregabalin combined with morphine in the management of pancreatic cancer pain. Methods: This study reviewed patients who were prescribed morphine and 150 mg/d pregabalin between 1 January 2017 and 10 November 2018 in our institute. The primary outcomes of this study were the average pain score and dose of morphine. Secondary outcomes included characters of breakthrough cancer pain, functional interference related to pain, anxiety/depression status, and incidence of treatment‐related adverse events during the study. Results: A total of 240 patients with pain related to pancreatic cancer were included in the study. The results showed that patients of both combination therapy group (pregabalin+morphine) and monotherapy group (morphine) achieved similar analgesic efficacy, demonstrated by NRS (2.4 ± 0.9 vs. 2.6 ± 0.9; combination vs. monotherapy) at the end of the study. Mean daily dose of morphine used in the combination group was significant lower compared to monotherapy group (39.5 ± 16.0 mg vs. 61.5 ± 19.3 mg, net difference 23.5, 95% CI: 18.4–28.6, p < 0.001). The change of functional interference score related to pain was significantly different between combination and monotherapy group (12.0 ± 0.4 vs. 9.8 ± 4.9; net difference, 2.3; 95% CI: 1.1–3.3; p < 0.001). Patients in combination therapy group had experienced shorter duration of breakthrough cancer pain than those in monotherapy group (X2p < 0.001, Cramer's V:0.36). The incidence of somnolence, dizziness, and cognitive dysfunction were significantly higher in the combination group compared to monotherapy group. No serious treatment‐related side effects were observed. Conclusions: The findings of this study supported the use of pregabalin with morphine to relieve pain in patients of pancreatic cancer. [ABSTRACT FROM AUTHOR]

The bioaccumulation and adverse effects of organophosphorus flame retardants (OPFRs) on human health have become a global concern. China produces the largest amount of OPFRs globally and has the highest global market share. However, little is known about its emission level and environmental cycling, thereby causing uncertainties in the assessment of the environmental and health impacts of OPFRs. We developed a gridded annual OPFRs emission inventory at 1/4° longitude by 1/4° latitude resolution over China from 2014 to 2018. The results show that the annual OPFRs emissions increased from approximately 670 tons/yr in 2014 to 1000 tons/yr in 2018 in China. Higher OPFR emissions were identified in Jiangxi, Shandong, Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD), and Pearl River Delta (PRD). In total, 2400 tons of OPFRs were released into the atmosphere during the multi-year period, in which production accounting for 56.6% of total OPFR emissions in China. An atmospheric transport model, the Canadian Model for Environmental Transport of Organochlorine Pesticides (CanMETOP), was employed to verify the gridded emission inventory and elucidate the atmospheric environmental fate of OPFRs. Modeled OPFRs in the air and soil agreed reasonably well with observed data, suggesting that the developed inventory was, to a large extent, reliable. The modeled atmospheric and surface soil concentrations of OPFRs across China ranged from 0 to 119 ng/m3 and 0 to 428 ng/g, respectively. East China is subjected to more intense OPFR contamination than the rest of the country. The results provide a valuable dataset and assessment of OPFRs, which may aid policy-makers and the scientific community in developing emission control strategies and evaluating the health and environmental consequences of OPFRs in China. [Display omitted] • OPFRs were released 4200 tons into the atmosphere in China from 2014 to 2018. • Annual OPFR emissions increased from 670 to 1000 tons/yr from 2014 to 2018. • The inventory was validated by an atmospheric transport model and monitored data. • Gridded OPFRs emission inventory was demonstrated to be reliable and accurate. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are omnipresent air pollutants with mutagenic and carcinogenic characteristics. Lanzhou city in Northwest China, where the first photochemical smog incident occurred in China, is located in an area characterized by mountain-valley topography. The city has been known as a heavy and petrochemical industry base and heavily contaminated by PAHs. There are large knowledge gaps in the understanding of atmospheric environmental fate of PAHs in Lanzhou city due to sparse observation data. We performed extensive numerical investigations of PAHs for August (summertime) and December (wintertime) of 2014 in Lanzhou city, using the Community Multiscale Air Quality (CMAQ) model, aiming to fill knowledge gaps in the spatial-temporal distribution and health consequences across the city. Strong seasonality in the atmospheric concentrations of PAHs was found, with high concentrations in winter and low concentrations in summer. The modeling results show high days in which daily air concentrations of BaP exceeding the level Ⅱ of Chinese National Standard (CNS) (2.5 ng/m3) in several August days in industrial suburb and urban area. In December, 77% and 80% of simulated BaP daily air concentrations were well above this national standard in the two areas. The modeled NAP and PHE in the atmosphere were predominantly in gas phase, whereas BaP was mainly in particulate phase. It was also found that the dry deposition dominated total PAHs deposition in Lanzhou. The incremental lifetime cancer risk (ILCR) ranged from 4.0 × 10−6 to 16.0 × 10−6, which were higher than the satisfactory risk level of 1.0 × 10−6, suggesting that local residents in Lanzhou city have a potential carcinogenic risk through exposure to ambient BaP. Especially, children had a higher exposure risk than adults. We suggest that the different actions in different regions of the city should be taken by the local government and those industries with high PAH emission, so as to reduce PAH contamination and risk. • The monthly average levels of BaP and PHE in winter were 2–3 times higher than in summer. • Dry deposition accounted for 99% of PAHs loading in the Lanzhou valley. • 12–16% of daily BaP levels exceeded CNS limit in suburb and downtown in summer. • 77–80% of daily BaP levels exceeded CNS limit in suburb and downtown in winter. • Children suffered from a higher inhalation exposure risk to BaP than adults. [ABSTRACT FROM AUTHOR]

In this study, we collected 308 serum samples from 17 to 20 year old first-year university students who were recruited from Lanzhou University in China a few days after their enrollment to measure the serum Pb, Cd, Hg, and As levels, and specific questionnaires for age, sex, settlement and dietary structure were designed. A 3-D atmospheric transport model was used to simulate the atmospheric concentration and dry deposition across China based on gridded Pb emission inventory to examine the association between the spatial distribution of serum concentrations and environmental fates of Pb. The mean serum Pb, Cd, Hg, and As concentrations averaged over all participating young students were 21.38, 1.46, 3.86, and 4.69 μg/L, respectively. The Pb, Cd, and Hg levels in 3%, 7%, and 20% serum samples exceeded the standards. The minimum serum As and Hg concentrations and the maximum serum Pb and Cd concentrations occurred in urban areas. Seafood diet habits (P < 0.05), sex (P < 0.05), and relocation (P < 0.01) caused significant differences in serum As, Pb, and Cd concentrations. A cluster analysis was carried out to classify the exposure pathways for target contaminants. The results indicated that 4 heavy metals in the serum of volunteers from northern China could be grouped into the same category, in which significant positive correlations were found between the serum heavy metal levels and background concentrations of surface soil. However, in other provinces and metropolises, the atmospheric pollution level played a critical role involving in the inhalation exposure pathway. We demonstrated that serum Pb levels in freshman students were related to the atmospheric transport and dry deposition of Pb. Unlabelled Image • HMs were determined in serums from first-year university students in China. • Pb, Cd, and Hg levels in some serum samples exceeded the standards. • Serum HMs were linked with seafood intake, gender and residential relocation. • Significant exposure pathway in northern China was associated with soil pollution. • Serum Pb levels in students were related to atmospheric emission and dry deposition. [ABSTRACT FROM AUTHOR]

As the largest petrochemical industrialized city in northwestern China since the 1950s, Lanzhou has been well-known for its heavy surface ozone pollution. Given abundant emission sources of ozone precursors and the favorable environmental conditions for O 3 formation, this study performed extensive atmospheric chemistry modeling investigations subject to 11 emission control scenarios. These scenarios increased and decreased emission levels of total volatile organic compound (TVOC) and nitrogen oxides (NO x), the two surface ozone (O 3) precursor gases, to examine the relationships between O 3 and NO x and TVOC. The modeling investigation was carried out for the summer of 2016 in the downtown and petrochemical industrial suburb in the city of Lanzhou. The results revealed that surface O 3 in the downtown area of Lanzhou was controlled by VOCs and in the petrochemical-industrialized western suburb by NO x. Higher ozone levels were simulated in the west suburb of the city as compared with the downtown area, agreeing with measured data. The relationships between modeled TVOC/NO x ratios and O 3 reductions, as well as the titration effect, were also discussed. The model results provided useful references for the mitigation strategy of ozone reduction in Lanzhou and other major cities in northwest China with similar climate and topography conditions. Unlabelled Image • Response of O 3 pollution to precursor chemicals in Lanzhou was simulated. • Multiple precursor emission control scenarios were implemented in simulations. • Modeled O 3 formation occurred in VOC and NO x control regimes in different regions. • Modeled results provided control strategies for precursor emissions across Lanzhou. [ABSTRACT FROM AUTHOR]

Background: Intra-operative use of opioid analgesics might have an impact on cancer recurrence and survival after surgery. The objective of this study was to investigate the association between the intra-operative fentanyl equivalents and survival outcomes in patients with primary liver cancer after receiving hepatectomy., Methods: This was a retrospective single-center cohort study, and clinical data of 700 patients with primary liver cancer who underwent hepatectomy in Harbin Medical University Cancer Hospital from September 2013 to August 2018 were reviewed. After propensity matching, 376 patients were included. Patients were divided into high-dose and low-dose groups according to the median intra-operative fentanyl equivalents (1.500 mg). Kaplan Meier curve and Cox proportional hazards regression model were used., Results: Results of univariable analysis showed there were no significant differences in recurrence-free survival (RFS) (p = 0.136) and overall survival (OS) (p = 0.444) between high-dose fentanyl equivalents and low-dose fentanyl equivalents group. The multivariable Cox regression analysis found that the dose of intra-operative fentanyl equivalents was not associated with RFS (HR: 1.119, 95%CI: 0.851-1.472, p = 0.422) or OS (HR: 0.939, 95%CI: 0.668-1.319, p = 0.715)., Conclusions: The amounts of intra-operative fentanyl equivalents had no impact on recurrence-free or overall survival in patients with primary liver cancer after curative hepatectomy., (© 2022 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

This study aims to investigate the prognostic impact of peripheral blood markers in patients with advanced non-small cell lung cancer (NSCLC) undergoing immunotherapy. In the current multicenter study, 157 advanced NSCLC cases treated by immunotherapy at three institutions were included. Biochemical parameters in baseline peripheral blood were collected. The associations between biochemical parameters and prognosis were investigated by the Kaplan-Meier survival analyses and Cox regression, and the predictive performances of biomarkers were evaluated via receiver operating characteristic analysis. The neutrophil-to-lymphocyte ratio (NLR) (progression-free survival [PFS]: hazard ratio [HR], 1.766; 95% confidence interval [CI], 1.311-2.380; p < 0.001; overall survival [OS]: HR, 1.283; 95% CI, 1.120-1.469; p < 0.001) and red blood cell distribution width (RDW) (PFS: HR, 1.052; 95% CI, 1.005-1.102; p = 0.031; OS: HR, 1.044; 95% CI, 1.001-1.091; p = 0.042) were revealed as independent predictors for both PFS and OS. In addition, NLR ≥3.79 (1-year PFS, 24.2% [95% CI, 15.2%-38.4%] versus 27.3% [95% CI, 18.2%-41.1%], p = 0.041; 1-year OS, 44.2% [95% CI, 32.5%-60.1%] versus 71.8% [95% CI, 60.6%-85.2%], p < 0.001) or RDW ≥44.8 g/L (1-year PFS, 19.2% [95% CI, 11.4%-32.3%] versus 31.7% [95% CI, 21.9%-46.0%], p = 0.049; 1-year OS, 54.0% [95% CI, 42.7%-68.3%] versus 63.1% [95% CI, 50.6%-78.6%], p = 0.014) was significantly correlated to poorer PFS and OS than NLR < 3.79 or RDW <44.8 g/L. Moreover, NLR and RDW achieved areas under the curve with 0.651 (95% CI, 0.559-0.743) and 0.626 (95% CI, 0.520-0.732) for predicting PFS, and 0.660 (95% CI, 0.567-0.754) and 0.645 (95% CI, 0.552-0.739), for OS. Therefore, PLR and RDW could help predict the immunotherapeutic efficacy of advanced NSCLC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liu, Zhao and Zhou.)

Objectives: This study evaluated the analgesic efficacy and safety of CT-guided iodine-125 ( 125 I) brachytherapy in patients with spinal metastasis-induced pain who were not suitable to receive radiotherapy., Methods: A cohort of 68 patients with spinal metastasis induced pain not fully relieved by opioids and did not receive external beam radiation therapy due to poor general status were enrolled and underwent CT-guided 125 I brachytherapy for analgesic treatment., Results: Patients were followed for 8 weeks after brachytherapy. Mean Numerical Rating Scale score before brachytherapy was 7.3±1.3 and decreased to 3.3±0.9, 2.6±0.8, 2.7±0.8, 2.9±0.9 and 3.3±1.1 at weeks 1, 2, 4, 6 and 8, respectively, after brachytherapy. Daily dose of morphine equivalent was 105.1±28.0 mg before brachytherapy and decreased to 45.3±13.7, 39.9±14.2, 40.4±14.9, 48.5±18.0 and 62.4±17.5 mg at weeks 1, 2, 4, 6 and 8, respectively, after brachytherapy. Patients had fewer daily episodes of breakthrough pain after brachytherapy (p<0.001). Patients had improvement in pain-related functional interference and in hospital anxiety and depression score after brachytherapy., Conclusions: CT-guided 125 I brachytherapy is an effective and safe intervention for patients with spinal metastasis-induced pain who are not able to receive radiation therapy., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)