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Abnormal glycosylation is a hallmark of tumor development, and tumor-associated carbohydrate antigens are potential immune targets for tumor therapy. Tumor-associated extracellular microvesicles are subcellular vesicles released from cell membranes that have immunogenicity similar to that of precursor cells. However, unmodified tumor-derived microvesicles have weaknesses, such as low immunogenicity, poor biostability, and short half-life in vivo. For the first time, we herein generated extracellular microvesicles containing modified tumor-associated carbohydrate antigens by constructing a cell line with highly expressed antigen-processing enzymes utilizing fluorine-modified monosaccharide substrates via a metabolic oligosaccharide engineering strategy. The microvesicles were applied to tumor immunity, achieving enhanced immunoprophylaxis and immunotherapy effects. Furthermore, the mechanisms of antitumor immunity were explored. Our findings may provide new insights into the adhibition of suitably modified extracellular microvesicles and the development of more effective carbohydrate-based anticancer vaccines.

Despite hypersialylation of cancer cells together with a significant upregulation of sialyltransferase (ST) activity contributes to the metastatic cascade at multiple levels, there are few dedicated tools to interfere with their expression. Although transition state-based ST inhibitors are well-established, they are not membrane permeable. To tackle this problem, herein, we design and construct long-circulating, self-assembled core–shell nanoscale coordination polymer (NCP) nanoparticles carrying a transition state-based ST inhibitor, which make the inhibitor transmembrane and potently strip diverse sialoglycans from various cancer cells. In the experimental lung metastasis and metastasis prevention models, the nanoparticle device (NCP/STI) significantly inhibits metastases formation without systemic toxicity. This strategy enables ST inhibitors to be applied to cells and animals by providing them with a well-designed nanodelivery system. Our work opens a new avenue to the development of transition state-based ST inhibitors and demonstrates that NCP/STI holds great promise in achieving metastases inhibition for multiple cancers.

The efficiency of targeted knock-in for cell therapeutic applications is generally low, and the scale is limited. In this study, we developed CLASH, a system that enables high-efficiency, high-throughput knock-in engineering. In CLASH, Cas12a/Cpf1 mRNA combined with pooled adeno-associated viruses mediate simultaneous gene editing and precise transgene knock-in using massively parallel homology-directed repair, thereby producing a pool of stably integrated mutant variants each with targeted gene editing. We applied this technology in primary human T cells and performed time-coursed CLASH experiments in blood cancer and solid tumor models using CD3, CD8 and CD4 T cells, enabling pooled generation and unbiased selection of favorable CAR-T variants. Emerging from CLASH experiments, a unique CRISPR RNA (crRNA) generates an exon3 skip mutant of PRDM1in CAR-Ts, which leads to increased proliferation, stem-like properties, central memory and longevity in these cells, resulting in higher efficacy in vivo across multiple cancer models, including a solid tumor model. The versatility of CLASH makes it broadly applicable to diverse cellular and therapeutic engineering applications.

Although aromaticity in 2D π-conjugated monocyclic and polycyclic molecules has been intensively studied, aromaticity in 3D fully π-conjugated molecular cages remains largely unexplored mainly due to the synthetic challenges. Herein, we report the facile synthesis of a π-conjugated molecular cage (1) containing four dimethylmethylene-bridged triphenylamine (DTPA) units via platinum-mediated assembly of four molecules of a pinacol borate trisubstituted DTPA derivative, followed by reductive elimination. 1has an open-cage structure, consisting of two isomeric trimers in trans- and cis-configurations, and an additional macrocycle across four DTPA units. Accordingly, the trans- (2) and cis- (3) macrocyclic trimers were also synthesized for comparison. 1–3can be facilely oxidized into their respective cations in which electrons are effectively delocalized at two or three dimensions. The detailed experimental measurements and theoretical calculations reveal that (1) the neutral cage 1shows localized aromaticity in individual benzene rings; (2) the dication 12+·2SbF6–displays bicyclic (anti)aromaticity with one macrocycle being aromatic (38π) and another macrocycle being antiaromatic (28π); on the other hand, the dications of the model compounds 2and 3are globally antiaromatic and nonaromatic, respectively; (3) the tetracation 14+·4SbF6–exhibits dominant 2D Hückel antiaromaticity in one of the macrocycles (36π). In addition, 12+·2SbF6–, 14+·4SbF6–, and 22+·2SbF6–possess open-shell singlet ground state with significant diradical character, while 32+·2SbF6–adopts a triplet ground state to release strain.

Dense glycosylation and the trimeric conformation of the human immunodeficiency virus-1 (HIV-1) envelope protein limit the accessibility of some cellular glycan processing enzymes and end up with high-mannose-type N-linked glycans on the envelope spike, among which the Man5GlcNAc2structure occupies a certain proportion. The Man5GlcNAc2glycan composes the binding sites of some potent broadly neutralizing antibodies, and some lectins that can bind Man5GlcNAc2show HIV-neutralizing activity. Therefore, Man5GlcNAc2is a potential target for HIV-1 vaccine development. Herein, a highly convergent and effective strategy was developed for the synthesis of Man5and its monofluoro-modified, trifluoro-modified, and S-linked analogues. We coupled these haptens to carrier protein CRM197 and evaluated the immunogenicity of the glycoconjugates in mice. The serological assays showed that the native Man5conjugates failed to induce Man5-specific antibodies in vivo, while the modified analogue conjugates induced stronger antibody responses. However, these antibodies could not bind the native gp120 antigen. These results demonstrated that the immune tolerance mechanism suppressed the immune responses to Man5-related structures and the conformation of glycan epitopes on the synthesized glycoconjugates was distinct from that of native glycan epitopes on gp120.

Carbohydrates play essential roles in various physiological and pathological processes. Trifluoromethylated compounds have wide applications in the field of medicinal chemistry. Herein, we report a practical and efficient trifluoromethylation of glycals by an electrochemical approach using CF3SO2Na as the trifluoromethyl source and MnBr2as the redox mediator. A variety of trifluoromethylated glycals bearing different protective groups are obtained in 60–90% yields with high regioselectivity. The successful capture of a CF3radical indicates that a radical mechanism is involved in this reaction.

Colorectal cancer (CRC) is a common malignancy involving multiple cellular components. The CRC tumor microenvironment (TME) has been characterized well at single-cell resolution. However, a spatial interaction map of the CRC TME is still elusive. Here, we integrate multiomics analyses and establish a spatial interaction map to improve the prognosis, prediction, and therapeutic development for CRC. We construct a CRC immune module (CCIM) that comprises FOLR2+macrophages, exhausted CD8+T cells, tolerant CD8+T cells, exhausted CD4+T cells, and regulatory T cells. Multiplex immunohistochemistry is performed to depict the CCIM. Based on this, we utilize advanced deep learning technology to establish a spatial interaction map and predict chemotherapy response. CCIM-Net is constructed, which demonstrates good predictive performance for chemotherapy response in both the training and testing cohorts. Lastly, targeting FOLR2+macrophage therapeutics is used to disrupt the immunosuppressive CCIM and enhance the chemotherapy response in vivo.

Ferroptosis is an iron-dependent form of cell death driven by biochemical processes that promote oxidation within the lipid compartment. Calcium (Ca2+) is a signaling molecule in diverse cellular processes such as migration, neurotransmission, and cell death. Here, we uncover a crucial link between ferroptosis and Ca2+through the identification of the novel tetraspanin MS4A15. MS4A15 localizes to the endoplasmic reticulum, where it blocks ferroptosis by depleting luminal Ca2+stores and reprogramming membrane phospholipids to ferroptosis-resistant species. Specifically, prolonged Ca2+depletion inhibits lipid elongation and desaturation, driving lipid droplet dispersion and formation of shorter, more saturated ether lipids that protect phospholipids from ferroptotic reactive species. We further demonstrate that increasing luminal Ca2+levels can preferentially sensitize refractory cancer cell lines. In summary, MS4A15 regulation of anti-ferroptotic lipid reservoirs provides a key resistance mechanism that is distinct from antioxidant and lipid detoxification pathways. Manipulating Ca2+homeostasis offers a compelling strategy to balance cellular lipids and cell survival in ferroptosis-associated diseases.

Globo H is a tumor-associated carbohydrate antigen (TACA), which serves as a valuable target for antitumor vaccine or cancer immunotherapies. However, most TACAs are T-cell-independent, and they cannot induce powerful immune response due to their poor immunogenicity. To address this problem, herein, several Globo H analogues with modification on the N-acyl group were prepared through a preactivation-based glycosylation strategy from the non-reducing end to the reducing end. These modified Globo H derivatives were then conjugated with carrier protein CRM197 to form glycoconjugates as anticancer vaccine candidates, which were used in combination with adjuvant glycolipid C34 for immunological studies. The immunological effects of these synthetic vaccine candidates were evaluated on Balb/c mice. The results showed that the fluorine-modified N-acyl Globo H conjugates can induce higher titers of IgG antibodies that can recognize the naturally occurring Globo H antigen on the surface of cancer cells and can eliminate cancer cells in the presence of a complement, indicating the potential of these synthetic glycoconjugates as anticancer vaccine candidates.

Bergenin, which is isolated from Bergeniaspecies, exhibits various pharmacological properties. In the search for new types of immunosuppressants, a series of bergenin derivatives were designed and synthesized, and their immunosuppressive effects were evaluated by the CCK-8 assay. The experimental data demonstrated that compounds 7and 13showed the strongest inhibition effects on mouse splenocyte proliferation (IC50= 3.52 and 5.39 μM, respectively). Further studies revealed that the inhibitory effect may come from the suppression of both IFN-γ and IL-4 cytokines. Alkylated derivatives of bergenin with n-hexyl and n-heptyl on the two phenolic hydroxyl groups showed better inhibitory activities. The hydrophobicity of bergenin derivatives, the configuration of the 4-OH in bergenin, and the ability to form hydrogen bonds of the substituents on the C-4 position are important to the immunosuppressive activity. This work proved that the modifications of bergenin may represent a new route to the discovery of a new class of immunosuppressive agents.

A novel transformation from rhamnose-type C-glycosides to 2-cyclopentenones is described. With the promotion of fluoroboric acid, C-glycosides underwent ring opening and subsequent Nazarov cyclization to afford 2-cyclopentenones in good to excellent yields. The solvent and the concentration of acid are crucial to the yield of this transformation.

A novel and efficient method to access phenolic glycosides has been established by using copper-mediated coupling reaction of aryl boronic acids with hemiacetals. The reaction enjoyed a wide range of substrate scope, and many phenolic glycosides can be synthesized in good yields.

We report a quite flexible naphthol-based cage (so-called “naphthocage”) which adopts a self-inclusion conformation in its free state and is able to bind singly charged organic cations extremely strongly (Ka> 107M–1). Ion-selective electrodes prepared with this naphthocage show a super-Nernstian response to acetylcholine. In addition, the highly stable complex (1010M–1) between ferrocenium and the naphthocage can be switched electrochemically, which lays a basis for its application in stimuli-responsive materials.

A novel glycosylation protocol has been established by using N-(glycosyloxy)acetamides as glycosyl donors. The N-oxyacetamide leaving group in donors could be rapidly activated in the presence of Cu(OTf)2or SnCl4under microwave irradiation. This glycosylation process afforded the coupled products in high yields, and the reaction enjoyed a broad substrate scope, even for disarmed donors and hindered acceptors. The easy availability of the donors, the high stability of N-(glycosyloxy)acetamides, and the small leaving group make this method very practical.

Background: As reported EGFR is a sialoglycoprotein with tyrosine kinase activity involved in control of cellular survival, multiplication, differentiation and metastasis. Dysregulation or aberrant expression of EGFR has been implicated in cell transformation and having oncogenic roles in a number of human cancers. Therefore EGFR has become a significant target for developing targeted therapy for cancer. Methods: A novel series of indole-3-carboxamide derivatives as EGFR inhibitors were designed, synthesized and evaluated for the anticancer activity in vitro against three EGFR high-expressed cancer cell lines (A549, HeLa, and SW480), one EGFR low-expressed cell line (HepG2) and one human liver normal cell line (HL7702) by MTT assay. Results: The target compounds 6c, 6f, 6i, 6j, 6l, 6r, 6u and 6x exhibited potent anticancer activities against the three tested cancer cell lines and weak cytotoxic effects on HepG2, which imply that the target compounds are probably effective in inhibiting EGFR. And they also did not show measurable activities in HL7702, which imply the target compounds are likely to overcome the nonspecific toxicity against normal cells. Particularly, the target compound 6x indicated equal to the positive control erlotinib. In addition, molecular docking studies demonstrated the target compound 6x may be the potential inhibitor to EGFR. Conclusion: A new EGFR inhibitor scaffold and a preliminary discussion on their SARs provide promising opportunities to guide further research on indole-3-carboxamide derivatives as novel anticancer agents.

A light-promoted approach to the synthesis of N-9 alkylated purine nucleoside derivatives has been developed.

Immunometabolism in the tumor microenvironment (TME) and its influence on the immunotherapy response remain uncertain in colorectal cancer (CRC). We perform immunometabolism subtyping (IMS) on CRC patients in the training and validation cohorts. Three IMS subtypes of CRC, namely, C1, C2, and C3, are identified with distinct immune phenotypes and metabolic properties. The C3 subtype exhibits the poorest prognosis in both the training cohort and the in-house validation cohort. The single-cell transcriptome reveals that a S100A9+macrophage population contributes to the immunosuppressive TME in C3. The dysfunctional immunotherapy response in the C3 subtype can be reversed by combination treatment with PD-1 blockade and an S100A9inhibitor tasquinimod. Taken together, we develop an IMS system and identify an immune tolerant C3 subtype that exhibits the poorest prognosis. A multiomics-guided combination strategy by PD-1 blockade and tasquinimod improves responses to immunotherapy by depleting S100A9+macrophages in vivo.

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O-GlcNAcylation of carbohydrate-responsive element-binding protein (ChREBP) is believed as an important modulator of ChREBP activities, however little direct evidence of O-GlcNAcylation on ChREBP and no exact O-GlcNAcylation sites have been reported so far. Here, we validate O-GlcNAcylation on ChREBP in cell-free coupled transcription/translation system and in cells by chemoenzymatic and metabolic labeling, respectively. Moreover, for the first time, we identify O-GlcNAcylation on Ser614 in the C-terminus of ChREBP by mass spectrometry and validate two important sites, Thr517 and Ser839 for O-GlcNAcylation and their function via molecular and chemical biological method. Under high glucose conditions, Ser514 phosphorylation enhances ChREBP O-GlcNAcylation, maintaining the transcriptional activity of ChREBP; Ser839 O-GlcNAcylation is essential for Mlx-heterodimerization and DNA-binding activity enhancement, consequently inducing transcriptional activity. Ser839 O-GlcNAcylation is also crucial for ChREBP nuclear export partially by strengthening interactions with CRM1 and 14-3-3. This work is a detailed study of ChREBP O-GlcNAcylation and highlights the biological consequences of the site-specific O-GlcNAcylation dynamics of ChREBP.

Some conserved glycans on the HIV envelope protein are targets of broadly neutralizing antibodies (bnAbs) of HIV. BnAbs provide a precise definition of broadly neutralizing epitopes on the envelope protein of HIV. These epitopes are promising for vaccine design. Many glycan-related antigens with high affinity to bnAbs have been tested as immunogens in vivo. However, it was found that no bnAb-like antibodies were induced. Vaccination with different immunogens containing the same neutralizing epitope may enhance the affinity maturation of antibodies which focus on the shared epitope. This combined immunization strategy showed great potential in peptide epitope-based vaccine design. However, it has not yet been explored on glycan-related epitopes to date. Herein, we take 2G12 as a model to validate this strategy on glycan-related epitopes. A high-affinity antigen of 2G12 was constructed by conjugating the D1 arm tetramannoside to bovine serum albumin. Then, the glycoconjugate was coimmunized with a recombinant gp120, which was expected to selectively benefit the induction of antibodies recognizing the neutralizing epitope of 2G12 on gp120. Mice were inoculated with the two antigens simultaneously or alternately to determine the suitable regimen for this strategy. The serological assays demonstrated that the antibody titers and subtypes responded to the whole gp120 were not improved, and the proportion of antibodies competitively bound to the 2G12 epitope was not enhanced significantly either. However, the coimmunized glycoconjugate selectively raised the proportion of antibodies recognizing D1 arm tetramannoside-related structures on gp120. These results provide important experience for the design of glycan-dependent bnAb-based vaccines.

Expansive soil of Nanyang Province in this experiment was as the research object and the different lime-mixed rates and basalt fiber-mixed rates on the strength characteristics of expansive soil were studied. The test results show that the maximum dry density and plasticity index of reinforced expansive soil were decreased along with the increased lime-mixed rates and the optimum water content was increased in the wake of the increased lime-mixed rates under the same compaction effort; unconfined compressive strength would be a peak along with the increased lime-mixed rates, ductility of reinforced expansive soil was enhanced by the basalt fiber; expansibility of reinforced expansive soil was slashed by lime and basalt fiber which was the dominant factor.

Bi ̊Char soil amendment has been accepted as a low-risk soil carbon sequestration method. Some other agricultural benefits also reported in previous researches. Two kinds of bi ̊Chars, produced from walnut shell and soft wood, with significantly different surface characteristics and a severe saline sandy loam soil was used in our research. Physical and chemical parameters of bi ̊Char and soil were analyzed. The results pressure plate analysis indicated that high surface area bi ̊Char can increase water retention and plant available water in severe saline agriculture soil, however, such effect wasn’t observed in all the low surface area bi ̊Char treatments. Based on these results, a simulated soil water loss experiment was conducted under 3 different temperatures (from 25 ̊C to 40 ̊C), with 4 bi ̊Char doses for 120 h. Our results shown that high dose of high surface area bi ̊Char can reduce the rate of soil water loss under high temperature. Such effect indicated that high surface area bi ̊Cahr can help soil hold more water under lab condition and simulated field condition. In bi ̊Char soil application, the interaction between bi ̊Char, soil and climate condition needs to be considered carefully to acheive optimum solution for both environmental and agricultural purposes.

Cyclic 3′5′ adenosine monophosphate (cAMP)-dependent-protein kinase (PKA) signaling is a fundamental regulatory pathway for mediating cellular responses to hormonal stimuli. The pathway is activated by high-affinity association of cAMP with the regulatory subunit of PKA and signal termination is achieved upon cAMP dissociation from PKA. Although steps in the activation phase are well understood, little is known on how signal termination/resetting occurs. Due to the high affinity of cAMP to PKA (KD∼ low nM), bound cAMP does not readily dissociate from PKA, thus begging the question of how tightly bound cAMP is released from PKA to reset its signaling state to respond to subsequent stimuli. It has been recently shown that phosphodiesterases (PDEs) can catalyze dissociation of bound cAMP and thereby play an active role in cAMP signal desensitization/termination. This is achieved through direct interactions with the regulatory subunit of PKA, thereby facilitating cAMP dissociation and hydrolysis. In this study, we have mapped direct interactions between a specific cyclic nucleotide phosphodiesterase (PDE8A) and a PKA regulatory subunit (RIαisoform) in mammalian cAMP signaling, by a combination of amide hydrogen/deuterium exchange mass spectrometry, peptide array, and computational docking. The interaction interface of the PDE8A:RIαcomplex, probed by peptide array and hydrogen/deuterium exchange mass spectrometry, brings together regions spanning the phosphodiesterase active site and cAMP-binding sites of RIα. Computational docking combined with amide hydrogen/deuterium exchange mass spectrometry provided a model for parallel dissociation of bound cAMP from the two tandem cAMP-binding domains of RIα. Active site coupling suggests a role for substrate channeling in the PDE-dependent dissociation and hydrolysis of cAMP bound to PKA. This is the first instance, to our knowledge, of PDEs directly interacting with a cAMP-receptor protein in a mammalian system, and highlights an entirely new class of binding partners for RIα. This study also highlights applications of structural mass spectrometry combined with computational docking for mapping dynamics in transient signaling protein complexes. Together, these results present a novel and critical role for phosphodiesterases in moderating local concentrations of cAMP in microdomains and signal resetting.

In order to implement the recognition automation of rock section pore images, a method combined K-means clustering with probabilistic neural network is proposed and applied to rock thin section images. Firstly, K-means clustering is used as segmentation algorithm, the rock images are divided into two types and extracted enough features and it is shown good classification recognition effect on testing dataset. Secondly, 100 pieces of rock image section are used as validation dataset, including 20 groups, each group has 5 images and 200 data samplings. Experiments show that the probabilistic neural network can be used as rock texture classifier, the average correct classification rate is around 95.12%, which can meet the practical application needs.

The corrosion inhibitor modified with acid activated attapulgite (CIATP) was prepared with acid activated attapulgite (HATP), styrene sulfonic sodium (SSS), maleic anhydride (MA) as monomers, water as solvent and ammonium persulfate as initiator. The effects of mass ratio of monomer, reaction temperature, the content of initiator and reaction time of preparing CIATP were investigated. The influences of the prepared CIATP concentration, time, pH and temperature of the system on the dispersing ferric oxide efficiency were also investigated. The obtained results showed that the prepared CIATP had excellent efficiency of dispersing ferric oxide, and nearly 98.98 % of dispersing ferric oxide efficiency was obtained. The experimental results indicate the corrosion inhibitor CIATP could be used in the corrosion inhibitor of high temperature water.

A series of copolymers modified with oxidized starch containing maleic anhydride (MA), styrene sulfonic sodium (SSS) and oxidized starch (OS) were synthesized by the free-radical polymerization. The polymerization is initiated by ammonium persulfate. The effects of content of monomer and initiator, reaction time, reaction temperature on dispersion ability for Fe2O3 were investigated by single factor experiment. The dispersion ability for Fe2O3 measured through UV spectroscopy was studied. The experimental results show that the copolymer has good dispersion ability for Fe2O3 when the mass proportion of monomers is OS:SSS:MA = 1:3:1, the mass fraction of initiator in total monomers is 10 %, reaction time is 5 h, and the reaction temperature is 70 oC. The morphology of the copolymer was observed by scanning electron microscope (SEM). The experimental results indicate that the prepared copolymer modified with oxidized starch could be used in the corrosion inhibitor of high temperature water.

The host-guest inclusion complex formation between 3, 3’-benzidine/β-cyclodextrin derivative (BDCD) and pesticide carbendazim was studied and characterized by TEM and XRD. The result showed that inclusion complex had hydrophobic small-molecule fluorophores. The fluorescence titration was performed to calculate binding constant, sensitivity factor and limit of detection of the resulting complex. Based on the enhancement of the fluorescence intensity of carbendazim produced throught complex formation, a new sensitive method for the determination of carbendazim was established. A linear relationship was obtained between the fluorescence intensity and carbendazim concentration in the range of 3.57 and 17.83 μmol/L. The correlation coefficient, the lowest limit of detection and RSD were 0.9916, 15.51 nmol/L and 2.13%, respectively. This method has better anti-interference ability and stability. The proposed method have been successfully applied to the determination of carbendazim pesticide residues in water, vegetable and fruit samples with satisfactory results, recoveries in the range of 87.56 % to 104.04 % were obtained.

The inclusion complex formation between fluorescent sensor 3, 3’-benzidine/β-cyclodextrin derivative (BDCD) and pesticide carbaryl was studied and characterized by TEM, XRD and fluorescence spectroscopy. The stability constant and the stoichiometry of complex were determined. Based on the enhancement of the fluorescence intensity of carbaryl produced through complex formation, a new sensitive method for the determination of carbaryl was established. The linear relationship between the fluorescence intensity and carbaryl concentration was obtained in the range of 0.60-3.00 μmol/L with a correlation coefficient of 0.9946. The detection limit was 5.12 nmol/L. This method has been successfully applied to the determination of carbaryl pesticide residue in water, fruit and vegetable samples with satisfactory results, recoveries in the range of 94.12 % to 105.88 % were obtained. The method is rapid, simple, direct, economical, sensitive and useful for carbaryl analysis.

For the identification complexity of rock microstructure, based on numerical analysis of rock section images, an automatic rock texture classification method and identification system is proposed in this paper. Digital grey image processing of rock thin section is used for features extraction, the features are then as inputs to the neural network model, the model output is the rock microstructure classification. 100 pieces of rock section images from Sulige region in Changqing Oilfield are used for the experiment; the whole dataset is randomly divided into 70 images for training datasets, 15 images for validation datasets and 15 images for testing datasets. It is shown that the correct classification rate for automatic identification of rock microstructure is about 93.3%. Therefore, the proposed method for solving geological problem is effective and can get a good identification performance for rock microstructure classification quickly and accurately.

With climate changes, soil may experience frequent drying-rewetting events. Water stress influences soil nitrogen transformation by affecting microbial growth and enzyme activities. The objective of this study was to determine effects of drying-rewetting cycles on soil N transformations and enzyme activities involved. The results show high correlations between soil inorganic N (NH4+-N & NO3--N) concentrations and soil moisture. Drying and rewetting events contributed to the accumulation of NO3--N. There was a significant correlation between NH4+-N/TDN and urease activities with a correlation coefficient of 0.88. Denitrifying enzyme activity showed a high positive correlation with soil moisture.

Unconfined compressive strength tests and calcium carbonate (CaCO3) quantitative chemical tests are conducted on artificially cemented sand which have different cement ratio (Cv) and curing time (t). Through the analysis of experimental results, the unconfined compressive strength (qu) of cemented sand are affected by curing time (t), cement ratio (Cv) and void ratio (η). Test results show that the longer the curing time (t), the lower the void/cement ratio (η/Cv) and the higher calcium carbonate/calcium hydroxide content ratio (CaCO3/Ca(OH)2 ratio or mC/mH), the higher the unconfined compressive strength (qu) of cemented sand. It is established the compressive strength equation based on the variables of cement ratio (Cv), void ratio (η) and curing time (t). By mC/mH-qu curve analysis, it is obtained the quantitative relation of chemical composition and mechanical strength.

TMS320F2812 is widely used in the design of embedded control system. Based on DSP TMS320F2812, the colliery high-voltage integrated protector which has setting protection, measurement, controlling and communication is developed. The design of AD module, CAN bus communication module and protection module of the integrated protector is elaborated. The structure design of its internal circuit and realization algorithms of part of modules are also given. Experimental results show that the protector achieves a good performance.

Synthetic neamine-heterocycle conjugates showed potent inhibitory effect on HIV replication.

The establishment of eco-industrial parks can not only reduce the costs of waste disposal and the purchase of raw materials, but also has a positive impact on both economy and environment. By setting Shanghai as an example, a model of the eco-industrial park was described and the design plan and operating procedures of the park were provided in this paper. Then the benefits of this park were discussed. It may bring about some practicable approaches for the development of China’s eco-industrial parks through a specific analysis as well as the presentation of an operating model.

More frequently drying-rewetting is likely to be expected for soils this century, with strong effect on nitrogen transformation. Experiments were conducted in semi-disturbed soils which were incubated under 4 different moisture regimes (dry wet\constant wet\constant dry\constant flooded) for 71 d. The results show that the dry soil has a rapid NO3--N increase after rewetting. Drying-rewetting increases soil nitrification which shows a "pulse" increasing. The drying and rewetting soil has the highest nitrification intensity when the soil moisture content (g/g) ranging at 15.82% ~ 17.06%. Drying-rewetting contributes to the accumulation of NO3--N.

The successful cultivation of aerobic granular sludge used for simultaneous nitrogen and phosphorus removal in sequencing batch reactor (SBR) was performed using a synthetic domestic wastewater and conventional flocculent activated sludge as seeding sludge. The removal efficiency of sludge for chemical oxygen demand (COD),ammonia nitrogen and phosphate was 92.4%,88.1% and 95.9%, respectively. After screening, a strain was obtained with high efficient in nitrogen and phosphorus removal. By analyzing, the strain was identified as Raoultella ornithinolytica. After strain accumulation, the strain cultured at 30℃ for 24h. The ammonia nitrogen and phosphate removal efficiency were 78.3% and 92%, respectively.

In this paper, a convenient approach to the synthesis of the repeating α‐(1→4)‐linked N‐acetyl galactosaminuronic acid units from the capsular polysaccharide of Salmonella typhiis reported. The exclusively α‐stereoselective glycosylation reactions were achieved by using oxazolidinone‐protected glycosides as building blocks based on a pre‐activation protocol. Di‐, tri‐, and tetrasaccharides were prepared by this short and efficient approach in high yields. The enzyme‐linked immunosorbent assay experiments show that our synthetic tri‐ and tetrasaccharide had much higher antigenic activities than previously reported ones in the inhibition of antibody binding by the native polysaccharide. The results demonstrate that the antigenic activities of saccharides can be strengthened greatly by increasing the number of acetyl groups present.

Stress-strain relationship of waste body under different side pressures, water contents and particle fractions are investigated in this paper. The bearing features of waste filled body of entry retaining besides gob-side entry retaining are: (1) filling waste gob-side entry retaining requires adequate horizontal restraint; (2) gangue water content has little effect on filling body intensity and waste in natural water content state can be used to fill in gob-side entry retaining; (3) stress and -strain relationship of waste body (grain size ranges from 0 to 10mm) is nonlinear. The bearing capacity can meet the requirement of beside gob-side entry retaining support. Based on above experimental results, the industrial roadway retained experiment is successful. The research results provide theory design basis for wide application.

The abnormal glycans expressed on the surface of tumor cells, known as tumor-associated carbohydrate antigens, increase the chance to develop carbohydrate-based anticancer vaccines. However, carbohydrate antigens pose certain difficulties, and the major drawback is their weak immunogenicity. To tackle this problem, numerous structurally modified STn antigens were designed and synthesized in this work. These synthetic antigens were screened in vitroby using competitive ELISA method, and the antigens with positive response were conjugated to the protein carrier for vaccination. The vaccination results on mice showed that some fluorine-containing modifications on the STn antigen can significantly increase the anti-STn IgG titers and improve the ratios of anti-STn IgG/IgM. The antisera can recognize the tumor cells expressing the native STn antigen.

Aminoglycosides are important broad-spectrum antibiotics used in the therapy of many microbial infections. As the bacterial resistance to antibiotic therapy is appearing as an increasingly significant threat to public health, the development of aminoglycoside antibiotics with extended antibacterial spectrum and potency, devoid of nephro- and ototoxicity, and evading the resistance process returns to the focus of researchers. In this review, various developments brought to the aminoglycoside family of antibiotics effective against resistant bacteria have been described, focused on chemical modifications, drug-modifying enzyme inhibitors, and conformationally constrained analogs, as well as related antibacterial compounds, with the hope to provide information useful in rational design of novel antibiotics addressing bacterial resistance, and paving the way for new perspectives in antimicrobial therapy.

A regioselective benzylation or P-methoxybenzylation of diols in azido-containing monosaccharide derivatives was reported, and the reaction was performed under the conventional reaction conditions (NaH/BnBr in DMF). The hydroxyl functionality adjacent to the azido group was benzylated selectively in good yields.

As the structural constituents of many naturally occurring molecules, synthesis of functionalized carbocyclic derivatives has been widely investigated. Among numerous approaches to construct carbocyclic compounds, there is an efficient way of forming carbocyclic derivatives by the use of various monosaccharides as chiral building blocks. In this review, synthetic conversions to functionalized carbocyclic compounds from exocyclic-olefinic saccharides and their applications to synthesis of some natural products or natural product-like analogues will be discussed. The emphases will be put on the latest methodology developments of ring-conversion rearrangement reactions catalyzed by metal catalysts.

The oligosaccharide residue in glycoconjugates located in cell membranes is responsible for intercellular recognition and interaction: it acts as a receptor for proteins, hormones, and microorganisms and governs immune reactions. These significant activities have stimulated great interest in the field of oligosaccharides and glycoconjugates. Although many advances have been made in the synthesis of oligosaccharides, more convenient and efficient methods are still needed. This review describes one of these new methods-the one-pot sequential glycosylation approach as a potent tool for oligosaccharide assembly. The oligosaccharide library construction in a one-pot fashion is also summarized.

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