Abstract-Crystalline lunar spherules (CLS) from three thin sections of Apollo 14 regolith breccias (143 18,6; 14318,48 and 14315,20) have been examined. The objects have been classified and their abundances, size distributions, bulk compositions, and (where possible) plagioclase compositions determined. By number, 64% consist predominantly of very tine-grained equant plagioclase grains but can also contain larger (-50 pm) feldspar crystals (type X), while 22% contain plagioclase lathes in a fine-grained mafic mesostasis (type Y ) . Plagioclase in both spherule types displays bright yellow cathodoluminescence that is conspicuous among the blue CL of the normal feldspar of the breccias. Type Z spherules (5%) contain feldspar with blue CL and minor amounts of olivine and pyroxene. Type Q spherules (4%) contain feldspar with yellow CL but in a luminescent mesostasis (of quartz or feldspar?). A few spherules are mixtures of type Y and type X textures. Most type X spherules, and a few type Y spherules, have fine-grained opaque rims. Compound objects were also found and consist of two or more CLS that appear to have collided while still plastic or molten. The CLS are thought to be impact spherules that crystallized in free flight, their coarse textures suggesting fairly slow cooling rates (-< 1 "Us). The abundance of the CLS resembles that of chondrules in the CM chondrite Murchison, and their cumulative size-frequency distributions are very similar to those of the chondrules in several meteorite classes. The bulk compositions of the CLS do not resemble regoliths at any of the Apollo sites, including Apollo 14, or any of the common impact glasses, but they do resemble the bulk compositions of several lunar meteorites and the impact glasses they contain. The Apollo 14 site is located on a region containing Imbrium ejecta, and we suggest that the CLS derive from the Imbrium impact. Ballistic calculations indicate that only impact events of this size on the Moon are capable of producing melt spherules with the required free flight times and slow cooling rates. Smaller impacts produce glassy spherules and agglutinates. As has been pointed out many times, the CLS have many properties in common with meteoritic chondrules. While much remains unclear, difficulties with a nebular origin and new developments in chondrule chronology, studies of asteroid surfaces and impact ejecta behavior, and the present observations indicate that meteoritic chondrules could have formed by impact.

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In recent years, the increase in non-Windows malware threats had turned the focus of the cybersecurity community. Research works on hunting Windows PE-based malwares are maturing, whereas the developments on Linux malware threat hunting are relatively scarce. With the advent of the Internet of Things (IoT) era, smart devices that are getting integrated into human life have become a hackers' highway for their malicious activities. The IoT devices employ various Unix-based architectures that follow ELF (Executable and Linkable Format) as their standard binary file specification. This study aims at providing a comprehensive survey on the latest developments in cross-architectural IoT malware detection and classification approaches. Aided by a modern taxonomy, we discuss the feature representations, feature extraction techniques, and machine learning models employed in the surveyed works. We further provide more insights on the practical challenges involved in cross-architectural IoT malware threat hunting and discuss various avenues to instill potential future research.

Because of unparalleled advantages over other cells, stem cells are widely used in genetic diagnosis, drug delivery, and regenerative medicine. However, because the content of stem cells in the organism is far from satisfactory, it is of great significance of stem cells to in vitro proliferation and differentiation. However, many stem cell cultures have low expansion efficiency and stem cells lose their value-adding ability and differentiation ability after many generations of culture. To solve these problems, people hope to more realistically simulate the microenvironment in which stem cells grow in vivo. Cell scaffolds gradually evolve from 2D structures to 3D structures. The addition of growth factors influences cell behavior from internal biochemical conditions and the development of smart bioreactors gradually make progress to more precise regulate the external conditions of stem cell. In this paper, the key factors for constructing the microenvironment of stem cell growth were analyzed, and we reviewed the application of bioreactors and 3D scaffolds in stem cell cultivation. Finally, this paper indicated the development directions of stem cell culture in vitro.

Some of the most primitive solar system materials available for study in the laboratory are the ordinary chondrites, the largest meteorite class. The size and distribution of the chondrules (silicate beads) and metal, which leads to the definition of the H, L, and LL classes, suggest sorting before or during aggregation. We suggest that meteorite parent bodies (probably asteroids) had thick dusty surfaces during their early evolution that were easily mobilized by gases evolving from their interiors. Density and size sorting would have occurred in the surface layers as the upward drag forces of the gases (mainly water) acted against the downward force of gravity. The process is analogous to the industrially important process of fluidization and sorting in pyroclastic volcanics. We calculate that gas flow velocities and gas fluxes for the regolith of an asteroid‐sized object heated by the impact of accreting objects or by 26Al would have been sufficient for fluidization. It can also explain, quantitatively in some cases, the observed metal‐silicate sorting of ordinary chondrites, which has long been ascribed to processes occurring in the primordial solar nebula. Formation of the chondrites in the thick dynamic regolith is consistent with the major properties of chondritic meteorites (i.e., redox state, petrologic type, cooling rate, matrix abundance). These ideas have implications for the nature of asteroid surfaces and the virtual lack of asteroids with ordinary chondrite‐like surfaces.

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Atezolizumab can reduce immunosuppression caused by T lymphocyte apoptosis in various cancer types. The current study aimed to investigate whether this drug can also alleviate immunosuppression during sepsis. For that purpose, a C57BL/6 mouse sepsis model was generated. Mice were randomly assigned to three groups: Sham, cecal ligation and puncture (CLP) and atezolizumab groups. Atezolizumab was administered in vivo by intraperitoneal injection. The expression of programmed death ligand-1 (PD-L1) on neutrophils and programmed death-1 (PD-1) on T lymphocytes was evaluated, and endotoxin concentration, intestinal permeability, ileum histopathological score and tight junction protein expression were assessed to determine the extent of disease in each group. The rate of T lymphocyte apoptosis was determined to assess the effects of atezolizumab on T lymphocyte apoptosis in vivo and in vitro . Survival times were also recorded to compare mouse prognosis during sepsis. In the CLP group, the proportion of PD-L1 + neutrophils was significantly higher at 48, 72 and 96 h in blood, and at 24, 48, 72 and 96 h in bone marrow, compared with those of the sham group (P<0.05). The proportion of PD-1 + T lymphocytes was also upregulated at 72 h in blood. In the atezolizumab group, endotoxin concentration, intestinal permeability and ileum histopathological score were lower compared with those in the CLP group (P<0.05), whereas the expression of claudin-1 and occludin proteins on ileum was higher compared with that in the CLP group (P<0.05). Both in vivo and in vitro experiments indicated that the rate of T lymphocyte apoptosis following atezolizumab treatment was lower compared with that in the CLP group (P<0.05). Survival analysis demonstrated that mice in the atezolizumab group survived longer compared with those in the CLP group (P<0.05). The current study demonstrated that treatment with atezolizumab may be an effective method for treating immunosuppression induced by sepsis.

Severe acute pancreatitis (SAP) is an acute inflammatory disease of the pancreas that involves various distant tissues and organs. This study aimed to investigate post-tissue injury repair by mesenchymal stem cells (MSCs) in a rat model of SAP. A total of 54 pathogen-free adult male SD rats were randomly assigned to the groups SAP, SAP + MSCs and sham-operated (SO). SAP was induced by 4% sodium taurocholate, and MSCs were injected via the dorsal penile vein 1 h later. The amylase activity, and tumor necrosis factor (TNF)-α and diamine oxidase (DAO) levels were measured with an enzyme-linked immunosorbent assay (ELISA), while the expression of aquaporin (AQP)-1 was evaluated by immunohistochemical staining. The pathological score of intestinal tissues was also compared among groups. Marked improvement in intestinal necrosis, villi shedding and infiltration of inflammatory cells was observed in the SAP + MSCs group compared to the SAP and SO groups. Amylase, TNF-α, and DAO levels were significantly increased in the SAP + MSCs group. The intestinal expression of AQP-1 was increased at 12 and 24 h post-MSC transplantation compared to the SO group. Rats of the SAP + MSCs group displayed higher pathological scores compared to the SAP group at all time points. Overall, these data showed that MSCs can inhibit systemic inflammation and reduce TNF-α release in a rat model of SAP-induced intestinal injury, suggesting that MSCs exert protective effects on the intestinal barrier during SAP.