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The paper presents the methodology and results of coreflooding, taking into account the decrease in the permeability caused by the migration of natural colloids during fluid injection. As a porous medium, core samples of consolidated slightly clayey sandstone from one of the oil fields of the Komi Republic (Russia) were used. The coreflooding methodology implied a cyclic change in the injection rate and excluded the influence of other factors such as creep and chemical mobilisation of colloids on permeability. It has been established that a decrease in pore pressure leads to a more intense decrease in permeability during injection, which most likely indicates additional mobilisation of colloids. An analysis of the coreflooding results showed that porous media with lower permeability are more sensitive to colloid migration and pore-pressure changes.

Quantum heat engines are expected to outperform the classical counterparts due to quantum coherences involved. Here we experimentally execute a single-ion quantum heat engine and demonstrate, for the first time, the dynamics and the enhanced performance of the heat engine originating from the Liouvillian exceptional points (LEPs). In addition to the topological effects related to LEPs, we focus on thermodynamic effects, which can be understood by the Landau-Zener-Stuckelberg process under decoherence. We witness a positive net work from the quantum heat engine if the heat engine cycle dynamically encircles an LEP. Further investigation reveals that, a larger net work is done when the system is operated closer to the LEP. We attribute the enhanced performance of the quantum heat engine to the LZS process, enabled by the eigenenergy landscape in the vicinity of the LEP, and the EP-induced topological transition. Therefore, our results open new possibilities to towards LEP-enabled control of quantum heat engines and of thermodynamic processes in open quantum systems., Comment: 7 pages, 3 figures, Supplementary materials can be found in the Download source

Phonon lasers, exploiting coherent amplifications of phonons, have been a cornerstone for exploring quantum phononics, imaging nanomaterial structures, and realizing force sensors or phonon frequency combs. Single-mode phonon lasers, governed by dispersive optomechanical coupling, have been recently demonstrated via levitating a nanoparticle using an optical tweezer. Such levitated optomechanical (LOM) devices, with fundamental minimum of noises in high vacuum, can flexibly control large-mass objects with no internal discrete energy levels. However, it is still elusive to realize nonlinear multi-frequency phonon lasing with levitated microscale objects, dominated instead by dissipative LOM coupling due to much stronger optical scattering loss. Here, we report such a nonlinear phonon laser by employing a Yb3+-doped active LOM system. We observe a 3-order of magnitude enhancement for the fundamental-mode phonon lasing, compared with that in its passive counterparts. Above the lasing threshold, higher-order mechanical sidebands emerge spontaneously. Coherent correlations are also identified for the phonon modes. Our gain-assisted dissipative LOM platform no longer relies on any complicated external feedback control. Our work drives LOM into a new regime where it becomes promising to study mechanical properties or quantum entanglement of typical micro-size objects, such as atmospheric particulates and living cells, and build levitated force sensors with these objects for biomedical or astronomical applications.

Renovation philosophy and residential construction mode are key problems encountered in the renovation of urban villages in China. Existing research fruits on renovation philosophy, and policies consider fairness and efficiency and cover-sharing research consensus. However, research on residential construction mode in renovation still faces challenges, such as weak relevant policy pertinence, insufficient objective references, and poor universality. In this study, the changes of the architectural spaces of a typical urban village community in Xi'an City from the beginning to the end of the renovation were discussed. The space requirements of different user groups were analyzed and summarized, and then adapted to the different types of building spaces. In addition, the residential construction model applicable to the inclusive renovation philosophy was established. Research results corroborated that the renovation of urban village should refer to its functional orientations in the community. The community-centered renovation residential district should also meet the requirements of different user groups in the community, including residential, living, and entertainment functions. Community-subcentered residential district should meet the space demands of residential and living functions. Community-subordinated residential district meets space demands of internal residents for residential and living. Moreover, residential district space is relieved by combining practical and certain spatial factors. In this research, the building space compositions of different user groups were reviewed and refined in the “bottom-up” pattern. Research conclusions provide design references for the practical renovation of urban villages.

Porcelain tooth technology is widely used in the treatment of oral diseases, but there are few reports on the possible occupational hazard factors in the process of porcelain tooth production. Porcelain teeth production will produced a large amount of silica dust and metal dust during the grinding process. The technical workers who have been engaged in this work for a long time are very prone to pneumoconiosis due to their poor personal protection awareness. This paper analyzed the clinical data of a pneumoconiosis patient engaged in porcelain tooth making, and analyzed the possible occupational hazard factors in the process of porcelain teeth production, so as to improve the understanding of relevant enterprises, technical workers and medical personnel on the disease and reduce the risk of porcelain teeth production workers suffering from pneumoconiosis.烤瓷牙技术广泛应用于口腔疾病的治疗，但目前对烤瓷牙制作过程中可能存在的职业病危害因素报道较少。烤瓷牙制作在研磨过程中会产生大量二氧化硅粉尘和金属烟尘，如个人防护意识差，长期从事此项工作的技术工人极易患尘肺病。本文通过分析一例从事烤瓷牙制作的尘肺病患者的临床资料，分析烤瓷牙制作过程中可能存在的职业病危害因素，以提高相关企业、技术工人和医务人员对该病的认识，降低烤瓷牙制作工人患尘肺病的风险。.

Neoadjuvant chemotherapy (NACT) is generally recommended for patients with locally advanced breast cancer which are inoperable, or for operable patients who wish to have breastconserving surgery...

BACKGROUND: This study aimed to investigate radiation-induced lymphopenia and its potential risk factors in patients with breast cancer receiving adjuvant radiotherapy. METHODS: Breast cancer patients received adjuvant radiotherapy (RT) at our hospital with peripheral lymphocyte counts (PLC) at pre-and immediately after RT (post-RT) were eligible. The primary endpoints were any grade of lymphopenia post-RT and nadir-PLC/pre-PLC

Purpose/Objective(s) In an era of increasingly use of axilla irradiation in high-risk breast cancer patients after breast-conserving surgery and sentinel lymph node (LN) biopsy, the optimal clinical target volume (CTV) for level I axilla (Ax-L1) LN is uncertain. We mapped the location of pretreatment LN metastases in the Ax-L1 of newly diagnosed breast cancer patients and propose modification of the CTV borders as defined by the Radiation Therapy Oncology Group (RTOG) breast cancer atlas. Further, we assessed the differences in dosimetric parameters of modified Ax-L1 planning target volume (PTV) and surrounding organs at risk (OAR) between whole breast irradiation with standard “high tangential” simplified IMRT (HT-sIMRT WBI) and whole breast plus Ax-L1 irradiation with VMAT (VMAT WBI+ Ax-L1). Materials/Methods We identified 76 newly diagnosed breast cancer patients with 1-4 positive LNs after curative-intent surgery and axillary lymph node dissection treated between 2016 and 2018. All patients had a pretreatment diagnostic computed tomography (CT) chest scan demonstrating involved Ax-L1 LNs. The locations of 116 involved Ax-L1 LNs were mapped onto simulation CT images of a standard patient and the appropriateness of RTOG atlas was assessed. A modified Ax-L1 CTV with better coverage for involved Ax-L1 LNs was proposed, and PTV was generated for plans. Standard “high tangential” sIMRT plans for WBI and VMAT plans for WBI+ Ax-L1 on each side (left side and right side) were designed with a prescription dose of 50 Gy in 25 fractions, and dosimetric parameters were compared. Results For the RTOG atlas, the mapped LNs were 70.7% (82/116) inside, 13.8% (16/116) marginal and 15.5% (18/116) outside the CTV borders. The RTOG atlas missed 29.3% of LNs: 50.0% (17/34) in the anterior, 23.5% (8/34) in the caudal, 14.7% (5/34) in the cranial, 11.8% (4/34) in the medial direction. Modification by extending 1 cm caudal and 0.5 cm anterior to the CTV borders of the RTOG atlas allowed the modified Ax-L1 CTV to encompass 90.5% (105/116) of LNs. For HT-sIMRT WBI and VMAT WBI+ Ax-L1 plans, the mean V50 of modified Ax-L1 PTV was 69.5% and 97.8%; the mean dose, V20 and V5 of ipsilateral lung were 8.9 Gy, 16.4%, 32.5% and 10.5 Gy, 20.8%, 33.8%; the mean heart dose in left-sided plans was 4.1 Gy and 3.0 Gy; the mean dose and V5 of liver in the right-sided plans were 1.5 Gy, 3.6% and 2.8 Gy, 10.3%, respectively. Conclusion According to the distribution of Ax-L1 LNs, the RTOG atlas might be insufficient for their coverage. We propose a modified Ax-L1 CTV with expansion of RTOG Ax-L1 CTV borders, most notably in the caudal and anterior directions. Standard “high tangential” sIMRT WBI plans failed to deliver a therapeutic dose adequately to the modified Ax-L1 PTV. VMAT plans intended for whole breast plus Ax-L1 irradiation provided adequate dose to Ax-L1 PTV without increasing the doses to OARs.

PURPOSE/OBJECTIVE(S) We conducted a phase 2 randomized trial comparing partial breast irradiation (PBI) with whole breast irradiation (WBI) after breast-conserving surgery (BCS) in patients with low-risk breast cancer. Here, we report the quality of life (QoL) at 1 year. MATERIALS/METHODS Women aged≥45 years with low-risk breast cancer after BCS were randomly assigned (1:1) to receive either PBI (40 Gy in 10 fractions over 2 weeks), or WBI (43.5 Gy in 15 fractions over 3 weeks) using tangential-field based IMRT technique. The primary endpoint, the incidence of ³ grade 2 acute and late toxicities, will be reported when participants have completed 5 years of follow-up. QoL was assessed at baseline (T0), end of radiotherapy (T1), and at 6 (T2), 12 (T3) months after radiotherapy (RT), using EORTC QLQ-C30 and QLQ-BR23 questionnaires. We calculated scores for all QOL domains, and focused on the difference in mean scale. Manne-Whitney U test was used to compare the difference between the two groups. Wilcoxon-signed rank test was used to examine the difference between T1, T2, T3 and T0 respectively in each group. The longitudinal analysis of QoL changes over time and between groups were assessed with generalized estimating equations (GEE) with log link function for mean scores. An interaction term between time and treatment group was used to assess if mean scale score change over time was statistically different between the two arms. Longitudinal analyses were mainly focused on selected subscales of the QLQ-C30 (global health status, physical functioning, role functioning, emotional functioning, social functioning, fatigue, pain, dyspnea, financial difficulties), and of the QLQ-BR23 (body image, future perspective, breast symptoms, and arm symptoms). The patients who completed the questionnaires at T0 and at least one other timepoint were eligible for analysis. All analysis was done according to treatment received (per protocol population). Two-sided P value

Purpose/Objective(s) To investigate the appropriate timing of radiotherapy (RT) after mastectomy and adjuvant chemotherapy for women with high-risk breast cancer. Materials/Methods A total of 584 patients with stage II-III breast cancer were analyzed from a randomized, open-label, phase 3 trial, which evaluated the non-inferiority of hypofractionated to conventional fractionated RT after mastectomy. All patients received mastectomy followed by adjuvant chemotherapy and RT without neoadjuvant treatments. Optimal cut-off value of the interval from the date of surgery to the starting date of RT (SRI) and the interval from the date of last-dose chemotherapy to the starting date of RT (CRI) for oncologic outcomes was calculated by Maxstat. Kaplan-Meier method was used to estimate the rates of locoregional recurrence (LRR), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS), and the differences were compared with log-rank test. Cox proportional hazards regression was performed for multivariate analysis. Results Median follow-up was 83.5 months (IQR 63-109). The median SRI was 168 days (range 93-357). The median CRI was 27 days (range 5-126). Compared to an SRI ≤165 days (5.5 months), an SRI > 165 days was associated with a significantly lower DFS rate (8-year 72.3% vs. 79.0%; P = 0.019), a higher DM rate (8-year 26.2% vs. 20.6%; P = 0.031), and a non-significantly higher LRR rate (8-year 9.0% vs. 6.0%, P = 0.065). Patients with an SRI > 180 days had a significantly lower OS rate compared with those with an SRI ≤180 days (8-year 72.2% vs. 84.1%; P = 0.012). Furthermore, CRI > 40 days was related to a significant decrease in DFS rate (8-year 67.0% vs. 76.9%; P = 0.002) and OS rate (8-year 69.0% vs. 83.0%; P = 0.002); and a significant increase in DM rate (8-year 33.4% vs. 21.8%; P = 0.001). No significant association between CRI > 40 days and LRR was found (8-year 10.4% vs. 7.2%; P = 0.238). After accounting for other known prognostic variables, SRI > 165 days, T stage and N stage remained significantly associated with inferior DM and DFS, while SRI > 180 days, T stage and N stage remained significantly associated with inferior OS. Meanwhile, CRI > 40 days, T stage and N stage were independently associated with inferior DM, DFS and OS. Conclusion Delay in initiating RT in patients with high-risk breast cancer is associated with inferior oncologic outcomes. We recommend RT should start within 165 days after mastectomy, and within 40 days after chemotherapy. NCT00793962

PURPOSE/OBJECTIVE(S) Lymphopenia is a known risk factor for poor outcome in cancer patients. This study aimed to validate radiation induced lymphopenia and study the potential risk factors in patients with breast cancer receiving adjuvant radiotherapy (RT). MATERIALS/METHODS This is a retrospective study of consecutive patients who received adjuvant radiotherapy. Eligible patients must have invasive breast cancer with peripheral lymphocyte counts (PLC) prior to and at the end of RT. Patient characteristics, tumor and treatment factors were collected for risk assessment. Data were presented as mean and 95% confidence interval (95% CI) unless otherwise specified. The primary endpoints were lymphopenia post-RT and nadir-PLC/pre-PLC < 0.8. The effects of potential risk factors were estimated using univariate and multivariable analyses. Matched analysis was used to evaluate the influence of volumetric modulated arc therapy (VMAT)technique. RESULTS Between 2015 and 2020, 735 patients met study criteria. The mean PLC was 1.58*109/L (95% CI: 1.54-1.62*109/L) before and 0.99*109/L (95% CI: 0.96-1.01*109/L) after RT (P < 0.001). At the end of RT, 60.5% (445/735, 95% CI: 60.4-60.6%) patients had lymphopenia, rendering 30.7%, 23.4%, 6.1% and 0.3% for grade 1, 2, 3, and 4, respectively. The reduction of PLC was most remarkable of all different kinds of the peripheral blood cells. Univariate and multivariable analyses showed radiotherapy technique with VMAT, mean lung dose and chemotherapy were significant risk factors (P < 0.05) for lymphopenia post-RT. RT technique was the only significant risk factor (P < 0.05) for nadir-PLC/pre-PLC < 0.8. Patients treated with VMAT technique had significantly greater reduction of PLC along with greater V5s of the lungs, even after matching mean lung dose and radiated treatment volume. CONCLUSION Lymphopenia is common in patients with breast cancer after adjuvant RT. RT technique is the only significant factor for both lymphopenia and nadir-PLC/pre-PLC < 0.8, suggesting the significance of RT optimization to minimize lymphopenia to improve treatment outcome.

Introduction Mir-146a-5p has been widely recognized as a critical regulatory element in the immune response. However, recent studies have shown that miR-146a-5p may also be involved in the development of Alzheimer disease (AD). Regrettably, the related mechanisms are poorly understood. Here, we investigated the effects of miR-146a in mice models and SH-SY5Y cells treated with amyloid β (Aβ)1–42. Methods To create a model of AD, SH-SY5Y cells were treated with Aβ1–42 and mice received intracerebroventricular injections of Aβ1–42. Then, the transcriptional levels of miR-146a were estimated by real-time PCR. We transiently transfected the miR-146a-5p mimic/inhibitor into cells and mice to study the role of miR-146a. The role of signaling pathways including p38 and reactive oxygen species (ROS) was studied by using specific inhibitors. Aβ and amyloid-beta precursor protein (APP)levels were measured by immunoblotting. Furthermore, Aβ expression was analyzed by immunofluorescence and histochemical examinations. Results Aβ1–42-stimulated SH-SY5Y cells displayed increased transcriptional levels of miR-146a and APP. Moreover, the p38 MAPK signaling pathway and ROS production were activated upon stimulation with a miR-146a-5p mimic. However, treatment with a miR-146a-5p inhibitor decreased the levels of APP, ROS, and p-p38 MAPK. A similar phenomenon was also observed in the animals treated with Aβ1–42, in which miR-146a upregulation increased the expression of Aβ, p-p38, and ROS, while the inhibition of miR-146a had the opposite effect. This suggests that miR-146a increases Aβ deposition and ROS accumulation via the p-p38 signaling pathway. Conclusions Our research demonstrates that miR-146a-5pa increases Aβ deposition by triggering oxidative stress through activation of MAPK signaling.

Background: According to the clinical manifestation, tuberculosis (TB) is divided into pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB). The incidence rate of EPTB has increased in many countries. The demographic and clinical characteristics of EPTB in China remain still unclear. Materials and methods: We retrospectively analyzed the medical records of 5,624 hospitalized patients with positive M. tuberculosis culture between January 2008 and June 2013 in Shandong province. We investigated the epidemiological, demographic, and clinical characteristics of patients with EPTB. Results: Among 5,624 hospitalized TB patients with positive M. tuberculosis culture, 4,277 (76.05 %) had PTB, 618 (10.99 %) had EPTB, and 729 (12.96 %) had both PTB and EPTB. The proportion of EPTB increased significantly from 6.97 % in 2008 to 19.98 % in 2012 (p