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Health care services during pregnancy and childbirth and after delivery are important for the survival and wellbeing of both the mother and the infant. The pregnancy outcomes at Kasungu District Hospital Maternity Ward have not been documented. Additionally, MDHS does not capture data regarding, prematurity, APGAR scores, and causes of maternal deaths and causes of neonatal deaths. Using Kasungu District Hospital Maternity Ward register, we aimed to describe the pregnancy outcomes at Kasungu Maternity Ward. From March 2016 to February 2017, data were available for 10,842 deliveries. The calculated Perinatal Mortality Rate (PMR) was about 77/1000 births and the Maternal Mortality Ratio (MMR) was 318 deaths per 100,000 live births. The Spontaneous Vertex Delivery (SVD) rate was 86% and the caesarean section rate was 10%. 1734 (16%) of all deliveries were premature borne between 28 and 36 gestation weeks. 1182 (11%) deliveries had missing APGAR scores and 81 neonates were born with 5 min Apgar scores less than 7. Adverse pregnancy outcomes occur at Kasungu Hospital Maternity Ward. More effort and resources are needed to decrease their occurrence.

Recently, intelligent transportation system based on image processing has been developed. In this paper, we propose a collision detection algorithm based on the analysis of motion vectors and the staying periods of vehicles in intersections. Objects in the region of interest are extracted from the subtraction image between background images based on Gaussian mixture model and input images. Collisions and traffic jams are detected by analysing measured motion vectors of vehicles and their staying periods in intersections. Experiments are performed on video sequences actually recoded at intersections. Correct detection rate and false alarm rate are 85.7% and 7.7%, respectively.

Purpose: To evaluate attenuation change of lung nodules and diagnostic performance of CT densitometry for detecting calcification according to tube voltage and current setting in low-dose CT using iterative reconstruction (IR). Material and Methods: CT images of an anthropomorphic phantom containing 14 artificial nodules (7-10 mm) with various mean attenuations (82-402 HU on standard dose) were obtained with 64- and 128-detector-row CT scanners using a standard (120kVp/100mA) and various low-dose settings (80, 100, and 120 kVp; 10-100 mAs) with IR. Mean and standard deviation (SD) of nodule attenuation (HU) were compared according to variation of tube voltages and current settings. As a threshold of 200 HU to determine calcified lesion, diagnostic performance of CT densitometry in low dose techniques was compared with those in standard dose CT. Results: Mean attenuation of nodules increased as the tube voltage decreased and SD increased as the tube voltage and current decreased in both CT scanners (p Conclusion: Although mean attenuation and SD of lung nodules changed variably according to combination of tube current and voltages, densitometry could be applicable for detection of calcification in low dose CT using IR techniques except very low tube current techniques.

Potential customers' willingness to pay (WTP) for a new product can be affected by their observing a posted price and this can be modeled in terms of an anchoring mechanism. A theoretical argument and mathematical proof are developed, showing that if customers use an asymmetric WTP anchoring mechanism, it will normally be optimal for firms to price higher than otherwise. Experimental evidence is provided supporting the notion that an asymmetric anchoring mechanism can be involved in purchase decisions.

Measuring consumers’ Willingness To Pay (WTP) without considering the level of uncertainty in valuation and the consequent risk premiums will result in estimates that are biased toward lower values. This research proposes a model and method for correctly assessing WTP in cases involving valuation uncertainty. The new method, called Risk Adjustment Mechanism (RAM), is presented theoretically and demonstrated empirically. It is shown that the RAM outperforms the traditional method for assessing WTP, especially in a context of a nonmarket good such as a totally new product.

Bacillus subtilis gene products TenA and TenI have been implicated in regulating the production of extracellular proteases, but their role in the regulation process remains unclear. The structural characterization of these proteins was undertaken to help provide insight into their function. We have determined the structure of TenA alone and in complex with 4-amino-2-methyl-5-hydroxymethylpyrimidine, and we demonstrate that TenA is a thiaminase II. The TenA structure suggests that the degradation of thiamin by TenA likely proceeds via the same addition-elimination mechanism described for thiaminase I. Three active-site residues, Asp44, Cys135, and Glu205, are likely involved in substrate binding and catalysis based on the enzyme/product complex structure and the conservation of these residues within TenA sequences. We have also determined the structure of TenI. Although TenI shows significant structural homology to thiamin phosphate synthase, it has no known enzymatic function. The structure suggests that TenI is unable to bind thiamin phosphate, largely resulting from the presence of leucine at position 119, while the corresponding residue in thiamin phosphate synthase is glycine.

The genes ( xylA ) encoding xylose isomerase (XI) from two Lactococcus lactis subsp. lactis strains, 210 (Xyl − ) and IO-1 (Xyl + ), were cloned, and the activities of their expressed proteins in recombinant strains of Escherichia coli were investigated. The nucleotide and amino acid sequence homologies between the xylA genes were 98.4 and 98.6%, respectively, and only six amino acid residues differed between the two XIs. The purified IO-1 XI was soluble with K m and k cat being 2.25 mM and 184/s, respectively, while the 210 XI was insoluble and inactive. Site-directed mutagenesis on 210 xylA showed that a triple mutant possessing R202M/Y218D/V275A mutations regained XI activity and was soluble. The K m and k cat of this mutant were 4.15 mM and 141/s, respectively. One of the IO-1 XI mutants, S388T, was insoluble and showed negligible activity similar to that of 210 XI. The introduction of a K407E mutation to the IO-1 S388T XI mutant restored its activity and solubility. The dissolution of XI activity in L. lactis subsp. lactis involves a series of mutations that collectively eliminate enzyme activity by reducing the solubility of the enzyme.

The double-bounded contingent valuation method (DBCVM) has long been criticized as an inappropriate estimation method because of respondents’ inconsistent behavior during a course of DBCVM survey. Many experimental studies have reported that two subsequent answers are not made independently, but the second answer depends upon the first. There are many kinds of hypotheses, each of which contends a different pattern of dependence of the answers. In this study, it will be tested which hypothesis is more appropriate in explaining the dependence of the answers. For the test, the DBCVM under uncertainty is newly developed here in which some uncertainties associated with the CVM are recognized and the risk premium plays a criterion for respondents to answer.

The thiO gene of Bacillus subtilis encodes an FAD-dependent glycine oxidase. This enzyme is a homotetramer with a monomer molecular mass of 42 kDa. In this paper, we demonstrate that ThiO is required for the biosynthesis of the thiazole moiety of thiamin pyrophosphate and describe the structure of the enzyme with N-acetylglycine bound at the active site. The closest structural relatives of ThiO are sarcosine oxidase and d-amino acid oxidase. The ThiO structure, as well as the observation that N-cyclopropylglycine is a good substrate, supports a hydride transfer mechanism for the enzyme. A mechanistic proposal for the role of ThiO in thiazole biosynthesis is also described.

The affinity of the maltose binding protein−nitro reductase fusion (MBP−NR) to electropolymerized films of N-(3-pyrrol-1-ylpropyl)-4,4‘-bipyridinium (PPB) has been studied in aqueous medium by the quartz crystal microbalance (QCM) technique. It was found that the MBP domain of MBP−NR exhibits specific binding toward PPB films through the maltose binding site and that the immobilized MBP−NR retains its enzymatic activity toward trinitrotoluene (TNT) reduction. Although some MBP−NR was nonspecifically adsorbed onto a maltose-covered PPB film as well as to a bare Au electrode, in both cases the adsorbed enzyme exhibited no catalytic activity. Nitro reductase (NR) also appeared to adsorb onto the PPB films but did not exhibit any enzymatic activity. The electropolymerization of N-(3-pyrrol-1-ylpropyl)-4,4‘-bipyridinium (PPB) onto a Au electrode in acetonitrile solution was studied by electrochemical quartz crystal microbalance (EQCM). It was found that the extent of polymerization upon pyrrole-centered oxidat...

The structural characterization of proteins expressed from the genome is a major problem in proteomics. The solution to this problem requires the separation of the protein of interest from a complex mixture, the identification of its DNA-predicted sequence, and the characterization of sequencing errors and posttranslational modifications. For this, the "top down" mass spectrometry (MS) approach, extended by the greatly increased protein fragmentation from electron capture dissociation (ECD), has been applied to characterize proteins involved in the biosynthesis of thiamin, Coenzyme A, and the hydroxylation of proline residues in proteins. With Fourier transform (FT) MS, electrospray ionization (ESI) of a complex mixture from an E. coli cell extract gave 102 accurate molecular weight values (2-30 kDa), but none corresponding to the predicted masses of the four desired enzymes for thiamin biosynthesis (GoxB, ThiS, ThiG, and ThiF). MS/MS of one ion species (representing approximately 1% of the mixture) identified it with the DNA-predicted sequence of ThiS, although the predicted and measured molecular weights were different. Further purification yielded a 2-component mixture whose ECD spectrum characterized both proteins simultaneously as ThiS and ThiG, showing an additional N-terminal Met on the 8 kDa ThiS and removal of an N-terminal Met and Ser from the 27 kDa ThiG. For a second system, the molecular weight of the 45 kDa phosphopantothenoylcysteine synthetase/decarboxylase (CoaBC), an enzyme involved in Coenzyme A biosynthesis, was 131 Da lower than that of the DNA prediction; the ECD spectrum showed that this is due to the removal of the N-terminal Met. For a third system, viral prolyl 4-hydroxylase (26 kDa), ECD showed that multiple molecular ions (+98, +178, etc.) are due to phosphate noncovalent adducts, and MS/MS pinpointed the overall mass discrepancy of 135 Da to removal of the initiation Met (131 Da) and to formation of disulfide bonds (2 x 2 Da) at C32-C49 and C143-C147, although 10 S-S positions were possible. In contrast, "bottom up" proteolysis characterization of the CoaBC and the P4H proteins was relatively unsuccessful. The addition of ECD substantially increases the capabilities of top down FTMS for the detailed structural characterization of large proteins.

A low-complexity algorithm for camera tamper detection is proposed which can detect various types of tamper attacks based on edge information. The performance of the proposed algorithm is evaluated for three types of tamper attacks and shown to achieve acceptable level of accuracy for all types of tamper attacks.

Xylose metabolism, a variable phenotype in strains of Lactococcus lactis , was studied and evidence was obtained for the accumulation of mutations that inactivate the xyl operon. The xylose metabolism operon ( xylRAB ) was sequenced from three strains of lactococci. Fragments of 4.2, 4.2, and 5.4 kb that included the xyl locus were sequenced from L. lactis subsp. lactis B-4449 (formerly Lactobacillus xylosus ), L. lactis subsp. lactis IO-1, and L. lactis subsp. lactis 210, respectively. The two environmental isolates, L. lactis B-4449 and L. lactis IO-1, produce active xylose isomerases and xylulokinases and can metabolize xylose. L. lactis 210, a dairy starter culture strain, has neither xylose isomerase nor xylulokinase activity and is Xyl − . Xylose isomerase and xylulokinase activities are induced by xylose and repressed by glucose in the two Xyl + strains. Sequence comparisons revealed a number of point mutations in the xylA , xylB , and xylR genes in L. lactis 210, IO-1, and B-4449. None of these mutations, with the exception of a premature stop codon in xylB , are obviously lethal, since they lie outside of regions recognized as critical for activity. Nevertheless, either cumulatively or because of indirect affects on the structures of catalytic sites, these mutations render some strains of L. lactis unable to metabolize xylose.

The genes encoding thiamine kinase in Escherichia coli ( ycfN ) and thiamine pyrophosphokinase in Bacillus subtilis ( yloS ) have been identified. This study completes the identification of the thiamine salvage enzymes in bacteria.

Two Bacillus subtilis genes encoding two proteins (currently annotated ThiD and YjbV) were overexpressed and characterized. YjbV has 4-amino-5-hydroxymethyl-2-methylpyrimidine and 4-amino-5-hydroxymethyl-2-methylpyrimidine pyrophosphate kinase activity and should be reannotated ThiD, and B. subtilis ThiD has pyridoxine, pyridoxal, and pyridoxamine kinase activity and should be reannotated PdxK.

While most of the proteins required for the biosynthesis of thiamin pyrophosphate have been known for more than a decade, the reconstitution of this biosynthesis in a defined biochemical system has been difficult due to the novelty of the chemistry involved. Here we demonstrate the first successful enzymatic synthesis of the thiazole moiety of thiamin from glycine, cysteine, and deoxy-D-xylulose-5-phosphate using overexpressed Bacillus subtilis ThiF, ThiS, ThiO, ThiG, and a NifS-like protein. This has facilitated the identification of the biochemical function of each of the proteins involved: ThiF catalyzes the adenylation of ThiS; NifS catalyzes the transfer of sulfur from cysteine to the acyl adenylate of ThiS; ThiO catalyzes the oxidation of glycine to the corresponding imine; and ThiG catalyzes the formation of the thiazole phosphate ring. The complex oxidative cyclization reaction involved in the biosynthesis of the thiamin thiazole has been greatly simplified by replacing ThiF, ThiS, ThiO, and NifS with defined biosynthetic intermediates in a reaction where ThiG is the only required enzyme.