Seasonal variations of sulfur aerosols at Zhongshan Station, East Antarctica

Observations of atmospheric methane-sulfonic acid (MSA) and non-sea-salt sulfate (nss-SO4 2−) from December 2010 to November 2011 at Zhongshan Station are presented in this paper. MSA and nss-SO4 2− average concentrations were 24.2 ± 37.9 ng·m-3 (0.5–158.3 ng·m-3 ) and 53.0 ± 82.6 ng·m-3 (not detected [n.d.]) – 395.4 ng·m-3 ), respectively. Strong seasonal variations of MSA and nss-SO4 2−, with maxima in austral summer and minima in winter, were examined. The high concentrations of sulfur compounds in December may be attributed the dimethyl sulfide (DMS) emissions from the marginal ice zone, when open water near the sampling site was important in impacting the sulfur species of January and February at Zhongshan Station. In austral winter, there was almost no phytoplanktonic activity in offshore waters, and atmospheric sulfur compounds likely had long-range transport sources

Expression of immune-response genes in lepidopteran host is suppressed by venom from an endoparasitoid, Pteromalus puparum

<p>Abstract</p> <p>Background</p> <p>The relationships between parasitoids and their insect hosts have attracted attention at two levels. First, the basic biology of host-parasitoid interactions is of fundamental interest. Second, parasitoids are widely used as biological control agents in sustainable agricultural programs. Females of the gregarious endoparasitoid <it>Pteromalus puparum </it>(Hymenoptera: Pteromalidae) inject venom along with eggs into their hosts. <it>P. puparum </it>does not inject polydnaviruses during oviposition. For this reason, <it>P. puparum </it>and its pupal host, the small white butterfly <it>Pieris rapae </it>(Lepidoptera: Pieridae), comprise an excellent model system for studying the influence of an endoparasitoid venom on the biology of the pupal host. <it>P. puparum </it>venom suppresses the immunity of its host, although the suppressive mechanisms are not fully understood. In this study, we tested our hypothesis that <it>P. puparum </it>venom influences host gene expression in the two main immunity-conferring tissues, hemocytes and fat body.</p> <p>Results</p> <p>At 1 h post-venom injection, we recorded significant decreases in transcript levels of 217 EST clones (revealing 113 genes identified <it>in silico</it>, including 62 unknown contigs) derived from forward subtractive libraries of host hemocytes and in transcript levels of 288 EST clones (221 genes identified <it>in silico</it>, including 123 unknown contigs) from libraries of host fat body. These genes are related to insect immune response, cytoskeleton, cell cycle and apoptosis, metabolism, transport, stress response and transcriptional and translational regulation. We verified the reliability of the suppression subtractive hybridization (SSH) data with semi-quantitative RT-PCR analysis of a set of randomly selected genes. This analysis showed that most of the selected genes were down-regulated after venom injection.</p> <p>Conclusions</p> <p>Our findings support our hypothesis that <it>P. puparum </it>venom influences gene expression in host hemocytes and fat body. Specifically, the venom treatments led to reductions in expression of a large number of genes. Many of the down-regulated genes act in immunity, although others act in non-immune areas of host biology. We conclude that the actions of venom on host gene expression influence immunity as well as other aspects of host biology in ways that benefit the development and emergence of the next generation of parasitoids.</p

Seasonal variations in aerosol compositions at Great Wall Station in Antarctica

High volume aerosol samplers at Great Wall Station in Antarctica were used to collect 73 aerosol samples between January 2012 and November 2013. The main ions in these aerosol samples, Cl−, NO3−, SO4 2−, Na+, K+, Ca2+, Mg2+, NH4+, as well as methane sulfonic acid, were analyzed using ion chromatography. Trace metals in these samples, including Pb, Cu, Cd, V, Zn, Fe, and Al, were determined by inductively-coupled plasma mass spectrometry. Results showed that sea salt was the main component in aerosols at Great Wall Station. Most ions exhibited significant seasonal variations, with higher concentrations in summer and autumn than in winter and spring. Variations in ions and trace metals were related to several processes (or sources), including sea salt emission, secondary aerosol formation, and anthropogenic pollution from both local and distant sources. The sources of ions and trace metals were identified using enrichment factor, correlation, and factor analyses. Clearly, Na+, K+, Ca2+, and Mg2+ were from marine sources, while Cu, Pb, Zn, and Cd were from anthropogenic pollution, and Al and V were mainly from crustal sources

Screening and characterization of the scFv for chimeric antigen receptor T cells targeting CEA-positive carcinoma

IntroductionChimeric antigen receptor T (CAR-T) cell therapy presents a promising treatment option for various cancers, including solid tumors. Carcinoembryonic antigen (CEA) is an attractive target due to its high expression in many tumors, particularly gastrointestinal cancers, while limited expression in normal adult tissues. In our previous clinical study, we reported a 70% disease control rate with no severe side effects using a humanized CEA-targeting CAR-T cell. However, the selection of the appropriate single-chain variable fragment (scFv) significantly affects the therapeutic efficacy of CAR-T cells by defining their specific behavior towards the target antigen. Therefore, this study aimed to identify the optimal scFv and investigate its biological functions to further optimize the therapeutic potential of CAR-T cells targeting CEA-positive carcinoma.MethodsWe screened four reported humanized or fully human anti-CEA antibodies (M5A, hMN-14, BW431/26, and C2-45), and inserted them into a 3rd-generation CAR structure. We purified the scFvs and measured the affinity. We monitored CAR-T cell phenotype and scFv binding stability to CEA antigen through flow cytometry. We performed repeated CEA antigen stimulation assays to compare the proliferation potential and response of the four CAR-T cells, then further evaluated the anti-tumor efficacy of CAR-T cells ex vivo and in vivo.ResultsM5A and hMN-14 CARs displayed higher affinity and more stable CEA binding ability than BW431/26 and C2-45 CARs. During CAR-T cell production culture, hMN-14 CAR-T cells exhibit a larger proportion of memory-like T cells, while M5A CAR-T cells showed a more differentiated phenotype, suggesting a greater tonic signal of M5A scFv. M5A, hMN-14, and BW431/26 CAR-T cells exhibited effective tumor cell lysis and IFN-γ release when cocultured with CEA-positive tumor cells in vitro, correlating with the abundance of CEA expression in target cells. While C2-45 resulted in almost no tumor lysis or IFN-γ release. In a repeat CEA antigen stimulation assay, M5A showed the best cell proliferation and cytokine secretion levels. In a mouse xenograft model, M5A CAR-T cells displayed better antitumor efficacy without preconditioning.DiscussionOur findings suggest that scFvs derived from different antibodies have distinctive characteristics, and stable expression and appropriate affinity are critical for robust antitumor efficacy. This study highlights the importance of selecting an optimal scFv in CAR-T cell design for effective CEA-targeted therapy. The identified optimal scFv, M5A, could be potentially applied in future clinical trials of CAR-T cell therapy targeting CEA-positive carcinoma

Application of Image Processing Variation Model Based on Network Control Robot Image Transmission and Processing System in Multimedia Enhancement Technology

The rapid development of the information age brings convenience to human life, but it also brings great challenges to information processing technology. Multimedia enhancement technology is an organic combination of multimedia technology and information processing technology, and it is also an important way of modern multimedia image information processing. However, its usefulness and effectiveness are increasingly negatively affected by the open information environment. The processing effect is also unable to meet the development requirements of the visual field. In order to improve this problem, this paper studied the image transmission and processing system of network-controlled robot on the basis of analyzing the characteristics of the problems existing in the current stage of multimedia technology. On this basis, a new image processing variational model was established and applied to multimedia enhancement technology, which improved the efficiency and effect of image information processing. Finally, the feasibility of its application function and performance was tested by experiments. The test results showed that in the difficult mode of the image processing task, the refresh time of the model in this paper in the multimedia enhancement technology was 1.13 s in total, which was not much different from the test results in the easy mode. Also, in the load stress test, the comprehensive test values under full-function operation and partial-function operation were 42.04% and 20.92%, respectively. Compared with the traditional model, the model in this paper has stronger carrying capacity in multimedia enhancement technology and has better processing ability and stability

Exploring the spatial-temporal relationship between rainfall and traffic flow: a case study of Brisbane, Australia

The impact of inclement weather on traffic flow has been extensively studied in the literature. However, little research has unveiled how local weather conditions affect real-time traffic flows both spatially and temporally. By analysing the real-time traffic flow data of Traffic Signal Controllers (TSCs) and weather information in Brisbane, Australia, this paper aims to explore weather's impact on traffic flow, more specifically, rainfall's impact on traffic flow. A suite of analytic methods has been applied, including the space-time cube, time-series clustering, and regression models at three different levels (i.e., comprehensive, location-specific, and aggregate). Our results reveal that rainfall would induce a change of the traffic flow temporally (on weekdays, Saturday, and Sunday and at various periods on each day) and spatially (in the transportation network). Particularly, our results consistently show that the traffic flow would increase on wet days, especially on weekdays, and that the urban inner space, such as the central business district (CBD), is more likely to be impacted by inclement weather compared with other suburbs. Such results could be used by traffic operators to better manage traffic in response to rainfall. The findings could also help transport planners and policy analysts to identify the key transport corridors that are most susceptible to traffic shifts in different weather conditions and establish more weather-resilient transport infrastructures accordingly

Representing Computational Relations in Knowledge Graphs Using Functional Languages (Short Paper)

Knowledge representation is the cornerstone of constructing a GKG. The existing representations of spatial and computational relations in GKGs, however, are inadequate. In this paper, we use DE-9IM to represent spatial topological relations. To represent computational relations, we use typed lambda calculus via its implementation in the functional language Haskell, in which functions are first-class primitives. We exemplify our ideas through some basic examples in Haskell

Mesenchymal stem cells derived from different origins have unique sensitivities to different chemotherapeutic agents

BMSCs (bone-marrow-derived mesenchymal stem cells) and ADSCs (adipose tissue-derived mesenchymal stem cells) are virtually identical in cell surface marker profile and differentiation potential. These cell populations have promising characteristics for clinical application. We have investigated the sensitivity of these cell populations to various chemotherapeutic agents by testing the inhibition of cell proliferation, low molecular DNA bands formation, in situ apoptosis, apoptosis-related gene expression and cell senescence after treatment. BU (busulfan), methotrexate and doxorubicin treatment led to a marked and dose-dependent reduction in cell viability compared with 5-FU (5-fluorouracil) treatment. Different expression patterns of apoptosis-related genes were found in the BMSCs and ADSCs following treatment with the agents, but no low molecular mass DNA bands were detected. BMSCs had a higher percentage of apoptotic and senescent cells following treatment with chemotherapeutic agents compared with ADSCs. These findings suggest that these two cell populations respond differently to chemotherapy treatment. ADSCs are more resistant than BMSCs to chemotherapy-induced senescence and apoptosis, indicating that they might be more advantageous to use in the clinic than BMSCs