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Venous thromboembolism (VTE) prevention is a key indicator for quality evaluation of hospital care. This paper summarized the construction and practice of full-process intelligent VTE prevention and control platform in perspectives of risk assessment and intelligent filling, AI predictive modeling, quality control, Disease-specific databases, follow-up applications, and provided reference for VTE prevention and treatment in the hospital. (静脉血栓栓塞症(VTE)规范化预防是评价医院医疗质量的重要指标。本研究阐述全流程智能化VTE防控平台构建过程中关于风险评估智能填充、AI预测模型构建、质控管理、专病数据库建立、随访小程序实施等的成效与经验, 以期为医院构建完善的VTE防治管理方案提供参考。)

The MnmE-MnmG complex is involved in tRNA modification. We have determined the crystal structure of Escherichia coli MnmG at 2.4-[Angstrom] resolution, mutated highly conserved residues with putative roles in flavin adenine dinucleotide (FAD) or tRNA binding and MnmE interaction, and analyzed the effects of these mutations in vivo and in vitro. Limited trypsinolysis of MnmG suggests significant conformational changes upon FAD binding. doi: 10.1128/JB.00650-09

For ferroresonant circuits, the sufficient condition for preventing fundamental ferroresonance (FF) from occurring is that there is no intersection between the voltage--current characteristic of the linear part of the circuit, and the saturated power frequency excitation characteristic of the nonlinear part. Based on this understanding, part II of this paper has presented a criterion for the possibility of FF in the form of an analytical expression which is composed of the essential parameters of the circuit. By giving the critical resistance value for damping FF, the expression clearly indicates not only the possibility of FF but also the methods for eliminating the FF. The possibility of FF is judged by comparing the critical resistance value with the real value. In the meantime, the expression suggests how to adjust the essential parameters to suppress FF. The criterion has been proven by both simulation results and field tests. With this criterion, the possibility and elimination of FF can be studied for the first time by a simple yet effective analytical method. Index Terms--Electromagnetic Transients Program (EMTP), ferroresonance, inductance, nonlinear circuits, potential transformer.

This paper has highlighted a major problem with the traditional excitation characteristic (TEC) of nonlinear inductors, in that the TEC contains harmonic voltages and/or currents, and has been used the way as if it were made up of pure fundamental voltage and current. In comparison to the TEC, a new concept, namely the power frequency excitation characteristic (PEC), which contains no harmonics, has been put forward. Two methods have been presented in obtaining the PEC. The first method is based on Electromagentic Transients Program simulation, resulting in discrete voltage and current pairs. This method essentially acts as a reference to validate the second one. The second method employs Fourier and Maclaurin series approximation techniques, and brings forth a simple yet effective analytical expression. The expression is proven to have satisfactory precision in the saturated region of the PEC, especially in the extremely saturated region. Index Terms--Electromagentic Transients Program (EMTP), ferroresonance, inductance, nonlinear circuits, potential transformer (PT).

Intracellular glucose in Escherichia coli cells imported by phosphoenolpyruvate-dependent phosphotransferase system-independent uptake is phosphorylated by glucokinase by using ATP to yield glucose-6-phosphate. Glucokinases (EC 2.7.1.2) are functionally distinct from hexokinases (EC 2.7.1.1) with respect to their narrow specificity for glucose as a substrate. While structural information is available for ADP-dependent glucokinases from Archaea, no structural information exists for the large sequence family of eubacterial ATP-dependent glucokinases. Here we report the first structure determination of a microbial ATP-dependent glucokinase, that from E. coli O157:H7. The crystal structure of E. coli glucokinase has been determined to a 2.3-[Angstrom] resolution (apo form) and refined to final [R.sub.work]/[R.sub.free] factors of 0.200/0.271 and to 2.2-[Angstrom] resolution (glucose complex) with final [R.sub.work]/[R.sub.free] factors of 0.193/0.265. E. coli GIK is a homodimer of 321 amino acid residues. Each monomer folds into two domains, a small [alpha]/[beta] domain (residues 2 to 110 and 301 to 321) and a larger [alpha]+[beta] domain (residues 111 to 300). The active site is situated in a deep cleft between the two domains. E. coli GlK is structurally similar to Saccharomyces cerevisiae hexokinase and human brain hexokinase I but is distinct from the ADP-dependent GlKs. Bound glucose forms hydrogen bonds with the residues Asn99, Asp100, Glu157, His160, and Glu187, all of which, except His160, are structurally conserved in human hexokinase 1. Glucose binding results in a closure of the small domains, with a maximal C[alpha] shift of ~10 [Angstrom]. A catalytic mechanism is proposed that is consistent with Asp100 functioning as the general base, abstracting a proton from the 06 hydroxyl of glucose, followed by nucleophilic attack at the [gamma]-phosphoryl group of ATP, yielding glucose-6-phosphate as the product.

At neutral-grounded substations, ferroresonance may happen upon switching a circuit breaker or disconnector, due to the saturated magnetizing characteristics of the bus PT. In this paper, a systematical method is presented to analyze and suppress the phenomenon. The scheme for suppressing the ferroresonance is to insert resistance, made from parallel-connected resistors, into the PT's wye secondary circuit. For a particular substation, it is first studied theoretically whether ferroresonance can possibly happen; and if so, a theoretical critical resistance is estimated to avoid the resonance. A practical one is then achieved by EMTP simulation on the basis of the theoretical one. The scheme for switching these resistors out of the circuit is to do that not all at once, but rather, in turn, to avoid exciting ferroresonance again. The appropriate resistance value of the resistors and the schedule of switching them out are also determined by EMTP simulation. A prototype was developed to fulfill the scheme, and proved to be effective by field tests. In addition, it is demonstrated that this kind of ferroresonance cannot be suppressed by adding resistance to the PT's delta secondary circuit. Index Terms--Circuit breaker, electromagnetic transient, EMTP, ferroresonance, potential transformer, substation.

The multiexponential metal oxide surge arrester (MOA) model currently used to simulate switching transients (current model), approximates the V-I characteristic of an MOA with several exponential segments. A test case illustrates a numerical oscillation caused by this model. The source of the oscillation is identified as the value jump of the derivative of the approximating function at the boundary point of adjacent exponential segments. The problem can be solved by using the Quasi-Newton method, but at the expense of computing time. A modified model is presented in this paper. This new model (proposed model) features a composite exponential and linear approximation to the V-I characteristic, and a monotonic derivative of the approximating function. The combination of the Newton method of iteration and the proposed model not only avoids numerical oscillation, but also has a better performance on computing time than the combination of the Quasi-Newton method and the current model. Index Terms--Electromagnetic transient, electromagnetic transient program (EMTP), iterative method, metal oxide surge arrester (MOA), modeling.

The histidine biosynthetic pathway is an ancient one found in bacteria, archaebacteria, fungi, and plants that converts 5-phosphoribosyl 1-pyrophosphate to L-histidine in 10 enzymatic reactions. This pathway provided a paradigm for the operon, transcriptional regulation of gene expression, and feedback inhibition of a pathway. L-histidinol dehydrogenase (HisD, EC 1.1.1.23) catalyzes the last two steps in the biosynthesis of L-histidine: sequential NAD-dependent oxidations of L-histidinol to L-histidinaldehyde and then to L-histidine. HisD functions as a homodimer and requires the presence of one [Zn.sup.2+] cation per monomer. We have determined the three-dimensional structure of Escherichia coli HisD in the apo state as well as complexes with substrate, [Zn.sup.2+], and [NAD.sup.+] (best resolution is 1.7 A). Each monomer is made of four domains, whereas the intertwined dimer possibly results from domain swapping. Two domains display a very similar incomplete Rossmann fold that suggests an ancient event of gene duplication. Residues from both monomers form the active site. [Zn.sup.2+] plays a crucial role in substrate binding but is not directly involved in catalysis. The active site residue His-327 participates in acid-base catalysis, whereas Glu-326 activates a water molecule. [NAD.sup.+] binds weakly to one of the Rossmann fold domains in a manner different from that previously observed for other proteins having a Rossmann fold.

The three-dimensional structure of Escherichia coli 2-amino-3-ketobutyrate CoA ligase reveals that it is a member of the alpha-family of pyridoxal phosphate-dependent enzymes and is a dimer with two active sites per dimer. Data show that the monomers contribute side chains to each of the active substrate binding site.

Crystal structure studies reveal that the action of thrombin is inhibited by a peptidyl pyridinium methyl ketone coded as P596 through the formation of a covalent bond between the serine residue at the active site of thrombin and the carbonyl carbon of the arginine residue in the inhibitor. The positive charge on the pyridinium nitrogen exposes the arginyl carbon to nucleophilic attack. Thrombin is an enzyme that is important in hemostasis and thrombosis.