Interest in utilizing biorenewable feedstocks to produce fuels and chemicals has risen greatly in the past decade due to the economic, political and environmental concerns associated with diminishing petroleum reserves. A fundamental challenge lying ahead in the development of efficient processes to utilize biomass feedstock is that, unlike their petroleum counterparts, biomass contains an excess amount of oxygen. Therefore, catalytic strategies such as dehydration and hydrogenolysis amongst others have been extensively studied as platform technologies for deoxygenation. In this review, we primarily discuss the catalytic dehydration of C 6 carbohydrates to 5-hydroxymethylfurfural, which has attracted much attention due to the versatility of using furanic compounds as an important platform intermediate to synthesize various chemicals. The emphasis is on the fundamental mechanistic chemistry so as to provide insights for further catalyst/catalytic system design. After separately discussing fructose and glucose dehydration, this review summarizes recent progress with bi-functional catalyst systems for tandem glucose/fructose isomerization and subsequent fructose dehydration, thereby realizing highly selective HMF production directly from the more abundant and cheaper C 6 sugar feedstock, glucose.

We report the catalytic conversion of glucose in high yields (62%) to 5-hydroxymethylfurfural (HMF), a versatile platform chemical. The reaction system consists of a Lewis acid metal chloride (e.g., AlCl 3) and a Bronsted acid (HCl) in a biphasic reactor consisting of water and an alkylphenol compound (2-secbutylphenol) as the organic phase. The conversion of glucose in the presence of Lewis and Bronsted acidity proceeds through a tandem pathway involving isomerization of glucose to fructose, followed by dehydration of fructose to HMF. The organic phase extracts 97% of the HMF produced, while both acid catalysts remain in the aqueous phase.

Glucose is a key energy supplier and nutrient for tumor growth. Herein, inspired by the glucose oxidase (GOx)-assisted conversion of glucose into gluconic acid and toxic H O , a novel treatment paradigm of starving-like therapy is developed for significant tumor-killing effects, more effective than conventional starving therapy by only cutting off the energy supply. Furthermore, the generated acidic H O can oxidize l-Arginine (l-Arg) into NO for enhanced gas therapy. By using hollow mesoporous organosilica nanoparticle (HMON) as a biocompatible/biodegradable nanocarrier for the co-delivery of GOx and l-Arg, a novel glucose-responsive nanomedicine (l-Arg-HMON-GOx) has been for the first time constructed for synergistic cancer starving-like/gas therapy without the need of external excitation, which yields a remarkable H O -NO cooperative anticancer effect with minimal adverse effect.

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This paper presents a new supervised method for vessel segmentation in retinal images. This method remolds the task of segmentation as a problem of cross-modality data transformation from retinal image to vessel map. A wide and deep neural network with strong induction ability is proposed to model the transformation, and an efficient training strategy is presented. Instead of a single label of the center pixel, the network can output the label map of all pixels for a given image patch. Our approach outperforms reported state-of-the-art methods in terms of sensitivity, specificity and accuracy. The result of cross-training evaluation indicates its robustness to the training set. The approach needs no artificially designed feature and no preprocessing step, reducing the impact of subjective factors. The proposed method has the potential for application in image diagnosis of ophthalmologic diseases, and it may provide a new, general, high-performance computing framework for image segmentation.

FTER RECORD HIGH LEVELS OF sexually transmitted diseases (STDs) in the late 1940s, China's socialist regime was remarkably successful in suppressing commercial sex and STDs from the 1950s through the 1970s. 1-3 However, in the last 2 decades, commercial sex has returned, and STD prevalence in China has increased. Human immunodeficiency virus (HIV) infection has begun to spread beyond the initial transmission pockets of injection drug users (IDUs) and blood transfusions. 4-6 If current infection trends persist, absolute numbers of individuals with HIV infection are projected to surpass current numbers in the United States within 2 years and those in South Africa (currently the highest) within a decade. 6,7 Reports from public health clinics and special studies of highrisk clinic patients, IDUs, and commercial sex workers reveal several dimensions of the problem. 8-10 China's public health reporting system tracks 8 STDs, including HIV and acquired immunodeficiency syndrome (AIDS), gonorrhea, syphilis, genital warts, nongonococcal urethritis/ cervicitis, genital herpes, lymphogranuloma venereum, and chancroid. The system does not track chlamydial infections. The reported annual incidence of all 8 infections combined was only 0.07 per 100 total population for the year 2000. 4,11 Asymptomatic infections, incomplete coverage, and other issues could lead to underreporting. 4 Chlamydia trachomatis and, to a lesser extent, Neisseria gonorrhoeae can remain asymptomatic, leading to a hidden epidemic. 12-15 In this study, we surveyed a probability sample from the Chinese adult population aged 20 to 64 years to determine the prevalence of in

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Cancer cells resist to the host immune antitumor response via multiple suppressive mechanisms, including the overexpression of PD-L1 that exhausts antigen-specific CD8 T cells through PD-1 receptors. Checkpoint blockade antibodies against PD-1 or PD-L1 have shown unprecedented clinical responses. However, limited host response rate underlines the need to develop alternative engineering approaches. Here, engineered cellular nanovesicles (NVs) presenting PD-1 receptors on their membranes, which enhance antitumor responses by disrupting the PD-1/PD-L1 immune inhibitory axis, are reported. PD-1 NVs exhibit a long circulation and can bind to the PD-L1 on melanoma cancer cells. Furthermore, 1-methyl-tryptophan, an inhibitor of indoleamine 2,3-dioxygenase can be loaded into the PD-1 NVs to synergistically disrupt another immune tolerance pathway in the tumor microenvironment. Additionally, PD-1 NVs remarkably increase the density of CD8 tumor infiltrating lymphocytes in the tumor margin, which directly drive tumor regression.