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Kuqa piedmont is the main battlefield of natural gas production in the oil field and the source of west-east gas transmission. The wellbore quality is related to the safety of well construction and production. However, the well cementation quality of the piedmont salt layer is affected by the narrow density window, low casing center degree, and narrow annular gap. Moreover, the qualified rate of well cementation has only been around 50% for many years, which seriously threatens the integrity and safety of the wellbore. Although wildcatters have conducted a series of technical research and practical exploration for many years, the actual application effect is not good. The problem of the inferior well cementation qualitied ratio in the gypsum salt layer is still prominent. Because of the above objective problems and technical limitations, this paper deeply analyzes the influencing factors of the well cementation, which has the qualitied ratio of the gypsum salt layer in the piedmont structure. Based on the three basic points of (1) casing running, (2) column centering, and (3) cementation leakage prevention, this paper studies and applies the combination cementation technology of reaming technology, coupled casing, and fine pressure control, aiming to provide new guidance for the development of the cementation operation of gypsum salt layer, the results of quality improvement and efficiency are remarkable.

In a recent clone-tracking experiment, millions of uniquely tagged hematopoietic stem cells (HSCs) and progenitor cells were autologously transplanted into rhesus macaques and peripheral blood containing thousands of tags were sampled and sequenced over 14 years to quantify the abundance of hundreds to thousands of tags or "clones." Two major puzzles of the data have been observed: consistent differences and massive temporal fluctuations of clone populations. The large sample-to-sample variability can lead clones to occasionally go "extinct" but "resurrect" themselves in subsequent samples. Although heterogeneity in HSC differentiation rates, potentially due to tagging, and random sampling of the animals' blood and cellular demographic stochasticity might be invoked to explain these features, we show that random sampling cannot explain the magnitude of the temporal fluctuations. Moreover, we show through simpler neutral mechanistic and statistical models of hematopoiesis of tagged cells that a broad distribution in clone sizes can arise from stochastic HSC self-renewal instead of tag-induced heterogeneity. The very large clone population fluctuations that often lead to extinctions and resurrections can be naturally explained by a generation-limited proliferation constraint on the progenitor cells. This constraint leads to bursty cell population dynamics underlying the large temporal fluctuations. We analyzed experimental clone abundance data using a new statistic that counts clonal disappearances and provided least-squares estimates of two key model parameters in our model, the total HSC differentiation rate and the maximum number of progenitor-cell divisions.

Civil aviation transportation equipment is more convenient and faster than other transportation tools and is an essential part of intelligent transportation. It is significant to study the reliability of positioning information and enhance traffic safety. Advanced receiver autonomous integrity monitoring (ARAIM) can provide vertical guidance during the different navigation stages in civil aviation fields. The traditional multiple hypothesis solution separation (MHSS) algorithm distributes the probability of hazardous misleading information (PHMI) and probability of false alarm (PFA) uniformly over all visible satellites resulting in reduced global availability of ARAIM. Aiming at this problem, we proposed an adaptive simulated annealing particle swarm optimization (ASAPSO) algorithm to redistribute integrity and continuity risks and establish a protection level optimization model. Based on the real BeiDou navigation satellite system/global positioning system (BDS/GPS) data, the experimental results show that the optimized algorithm can reduce the vertical protection level (VPL), and the ARAIM global availability of BDS/GPS is improved by 1.73%∼2.73%. The optimized algorithm can improve the availability of integrity monitoring at different stages of the navigation system and provide a basis for ensuring the reliability of the positioning results., Author(s): Ershen Wang [1,2]; Xiaozhu Shi [1,3]; Xidan Deng [2]; Jing Gao (corresponding author) [4]; Wei Zhang [1,3]; Huan Wang [2]; Song Xu [2] 1. Introduction The BDS-3 satellite navigation [...]

Micro laser powder bed fusion (μLPBF), for the first time, enables fabrication of low-density triply periodic minimal surface (TPMS) shell lattices with smaller feature size. However, the understandings on the mechanical responses of lightweight TPMS structures by μLPBF are yet to be updated. Herein, stainless steel 316L TPMS shell lattices (i.e., Primitive (P), Diamond (D) and Gyroid (G)) with different shell thicknesses and cell orientations were fabricated by µLPBF. Low-density TPMS structures with shell thickness as small as ∼100 μm and relative density ∼5 % were realized. Quasi-static compression tests and finite element modelling were conducted to study their compressive responses. Their light-weighting potential related to the scaling behavior of mechanical properties as a function of relative density was analyzed. Results show with increasing relative density, the deformation mechanism transforms from localized collapse to homogeneous bulk deformation. P-type TPMS exhibits the highest anisotropy of stiffness, strength and energy absorption capability, while G-type TPMS is near-isotropic. [100] oriented d-type TPMS shows the highest strength and best light-weighting potential. Compared with conventional LPBF, the µLPBF TPMS structures demonstrate higher mechanical properties and superior light-weighting potential. Overall, this work highlights the superiority of the µLPBF technology in fabricating lightweight TPMS structures for mechanical applications.

ObjectiveTo evaluate the effectiveness and advantages of a new method for calculating breast tumor volume based on an automated breast ultrasound system (ABUS).MethodsA total of 42 patients (18–70 years old) with breast lesions were selected for this study. The Ivenia ABUS 2.0 (General Electric Company, USA) was used, with a probe frequency of 6–15 MHz. Adobe Photoshop CS6 software was used to calculate the pixel ratio of each ABUS image, and to draw an outline of the tumor cross-section. The resulting area (in pixels) was multiplied by the pixel ratio to yield the area of the tumor cross-section. The Wilcoxon signed rank test and Bland-Altman plot were used to compare mean differences and mean values, respectively, between the two methods.ResultsThere was no significant difference between the tumor volumes calculated by pixel method as compared to the traditional method (P>0.05). Repeated measurements of the same tumor volume were more consistent with the pixel method.ConclusionThe new pixel method is feasible for measuring breast tumor volume and has good validity and measurement stability.

Myricetin, a polyhydroxyflavone compound, is one of the main ingredients of various human foods and therefore also known as dietary flavonoids. Due to the continuous emergence of resistant strains of herpesviruses, novel control measures are required. In the present study, myricetin exhibited potent antiviral activity against pseudorabies virus (PRV), a model organism of herpesvirus. The suppression rate could reach up to 96.4% at a concentration of 500 μM in cells, and the 50% inhibitory concentration (IC50) was 42.69 μM. Moreover, the inhibitory activity was not attenuated by the increased amount of infective dose, and a significant reduction of intracellular PRV virions was observed by indirect immunofluorescence. A mode of action study indicated that myricetin could directly inactivate the virus in vitro, leading to inhibition of viral adsorption, penetration and replication in cells. In addition to direct killing effect, myricetin could also activate host antiviral defense through regulation of apoptosis-related gene expressions (Bcl-2, Bcl-xl, Bax), NF-κB and MAPK signaling pathways and cytokine gene expressions (IL-1α, IL-1β, IL-6, c-Jun, STAT1, c-Fos, and c-Myc). In PRV-infected mouse model, myricetin could enhance the survival rate by 40% at 5 days post infection, and viral loads in kidney, liver, lung, spleen, and brain were significantly decreased. The pathological changes caused by PRV infection were improved by myricetin treatment. The gene expressions of inflammatory factors (MCP-1, G-CSF, IL-1α, IL-1β, and IL-6) and apoptotic factors (Bcl-xl, Bcl-2, and Bax) were regulated by myricetin in PRV-infected mice. The present findings suggest that myricetin can effectively inhibit PRV infection and become a candidate for development of new anti-herpesvirus drugs.

Additive manufacturing (AM) was recently developed for building intricate devices in many fields. Especially for laser powder bed fusion (LPBF), its high-precision manufacturing capability and adjustable process parameters are involved in tailoring the performance of functional components. NiTi is well-known as smart material utilized widely in biomedical fields thanks to its unique superelastic and shape-memory performance. However, the properties of NiTi are extremely sensitive to material microstructure, which is mainly determined by process parameters in LPBF. In this work, we choose a unique NiTi intricate component: a robotic cannula tip, in which material superelasticity is a crucial requirement as the optimal object. First, the process window was confirmed by printing thin walls and bulk structures. Then, for optimizing parameters precisely, a Gyroid-type sheet triply periodic minimal-surface (G-TPMS) structure was proposed as the standard test sample. Finally, we verified that when the wall thickness of the G-TPMS structure is smaller than 130 μm, the optimal energy density changes from 167 J/m3 to 140 J/m3 owing to the lower cooling rate of thinner walls. To sum up, this work puts forward a novel process optimization methodology and provides the processing guidelines for intricate NiTi components by LPBF.