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Cost-effective hydrolysis of biomass into sugars for biofuel production requires high-performance low-cost glycoside hydrolase (GH) cocktails that are active under demanding process conditions. Improving the performance of GH cocktails depends on knowledge of many critical parameters, including individual enzyme stabilities, optimal reaction conditions, kinetics, and specificity of reaction. With this information, rate- and/or yield-limiting reactions can be potentially improved through substitution, synergistic complementation, or protein engineering. Given the wide range of substrates and methods used for GH characterization, it is difficult to compare results across a myriad of approaches to identify high performance and synergistic combinations of enzymes. Here, we describe a platform for systematic screening of GH activities using automatic biomass handling, bioconjugate chemistry, robotic liquid handling, and nanostructure-initiator mass spectrometry (NIMS). Twelve well-characterized substrates spanning the types of glycosidic linkages found in plant cell walls are included in the experimental workflow. To test the application of this platform and substrate panel, we studied the reactivity of three engineered cellulases and their synergy of combination across a range of reaction conditions and enzyme concentrations. We anticipate that large-scale screening using the standardized platform and substrates will generate critical datasets to enable direct comparison of enzyme activities for cocktail design.

Objective: To investigate the operative procedure and the therapeutic effects of minimally invasive incision and percutaneous pinning in operative treatment of Gartland type III humeral supracondylar fracture in children., Methods: From September 2002 to July 2009, 189 patients with Gartland type III humeral supracondylar fracture were treated with minimally invasive incision and percutaneous pinning. There were 137 males and 52 females, aged from 1 to 13 years (6.2 years on average). Injury was caused by sports in 173 cases, by traffic accident in 9 cases, by falling from height in 5 cases, and by earthquake in 2 cases. All fractures were closed fractures, complicating others fracture in 11 cases, radial nerve injury in 36 cases, median nerve injury in 5 cases, ulnar nerve injury in 2 cases, and brachial artery injury in 2 cases. The time from injury to hospitalization was 1 hour to 10 days. Neurovascular repair was performed at the same period., Results: All incisions healed by first intention, no related complications occurred. A total of 143 patients were followed up 5 months to 5 years (12 months on average). X-ray films showed fracture healed within 2-4 months (2.5 months on average). Cubitus varus occurred in 6 cases, but the functions of elbow flexion and extension were good; 2 cases were given distal humeral wedge osteotomy and 4 cases continued keeping the functional training. According to the Flynn et al criteria, the results were excellent in 121 cases, good in 15 cases, and fair in 7 cases; the excellent and good rate was 95.1%. Only a small incision scar was found, the function returned to normal in the cases complicated by nerve and blood vessel injury., Conclusion: Minimally invasive incision and percutaneous pinning for operative treatment of Gartland type III humeral supracondylar fracture in children is a safe and effective surgical procedure, which has minimal trauma, short surgery time, quick recovery, simple operation, and can be effective in reducing the complications.

Currently, herbicides are widely used in various combinations at many stages of cultivation and during postharvest storage. There are increasing concerns about the public health impact of herbicide degradation byproducts that may be present in water bodies used either as drinking water or for recreational purposes. This work investigated the sulfonic acid and oxanilic acid degradation products of metolachlor, alachlor, acetochlor, and propachlor in a variety of water bodies. The objective was to develop a fast, accurate, and easy method for quantitative analysis of herbicide degradation products using liquid chromatography with tandem mass spectrometry without solid phase extraction, but performing levels of detection lower than those obtained in previous studies with solid phase extraction. This research also screened 68 water samples, both untreated source water and treated water, from 34 water treatment plants in Missouri. Finally, it examined seasonal trends in levels of those degradation products by collecting and testing samples monthly. This highly sensitive method can analyze these degradation products to low ng/L levels. The method limit of quantification ranges from 0.04 to 0.05 ppb for each analyte; and quantitative analyses show a precision with RSDs of around 0.6% to 3% in treated water and 2% to 19% in untreated source water. Concentrations of alachlor ESA, acetochlor OA, metolachlor OA, and metolachlor ESA were detected from the Missouri River and the Mississippi River water bodies in summer time. Occurrences of these compounds in treated water samples are all lower than those in the untreated source water samples.