Rasch models overview

This overview of Rasch measurement models begins with a conceptualization of our continuous experiences that are often captured as discrete observations. It goes on to discuss the properties that are require of measures if they are to transcend the occasion in which they were collected, and concludes with a discussion the spiral of inferential development. This is followed by a discussion of the mathematical properties of the Rasch family of models that allow the transformation of discrete deterministic counts into continuous probabilistic abstractions on which science is based. The overview concludes with a discussion of six of the family of Rasch models, Binomial Trials, Poisson Counts, Rating Scale, Partial Credit, and Ranks and the types of data for which these models are appropriate.     

Simulation framework for the verification of PLC programs in automobile industries

The objective of this study is to propose a framework of virtual plant models for the verification of PLC logic through modeling and simulation. The proposed virtual plant model consists of three types of object: the virtual device model (object model), the intermediary transfer model (functional model), and the PLC program & HMI (dynamic model). A virtual device model consists of a physical part, which is used to represent the properties of a real device and a logical part, which is used to manage the device's operation. For the fidelity of the virtual plant model, an intermediary transfer model controls the virtual device through a PLC program and sends information on the virtual device's state to the supervisory control model. Moreover, the PLC program and HMI are used for constructing communication environments similar to a real manufacturing line. For the implementation of the proposed virtual plant model, this study employs an I/O model based on the formalism of Automata and Discrete Event Systems Specifications (DEVS). As a result of the application to a car assembly line, 18 error codes are detected through the manual mode and have been revised. Finally, we can confirm there is no sequential error in the PLC program by checking the time chart. Moreover, the bottleneck and ramp-up/down times are reduced when a manufacturing system/line is built.     

Hyperprolactinemia in males with systemic lupus erythematosus

Alanine dehydrogenase [EC 1. 4. 1. 1] was purified to homogeneity from a crude extract of Enterobacter aerogenes ICR 0220. The enzyme had a molecular mass of about 245 kDa and consisted of six identical subunits. The enzyme showed maximal activity at about pH 10.9 for the deamination of L-alanine and at about pH 8.7 for the amination of pyruvate. The enzyme required NAD+ as a coenzyme. Analogs of NAD+, deamino-NAD+ and nicotinamide guanine dinucleotide served as coenzymes. Initial-velocity and product inhibition studies suggested that the deamination of L-alanine proceeded through a sequential ordered binary-ternary mechanism. NAD+ bound first to the enzyme, followed by L-alanine, and the products were released in the order of ammonia, pyruvate, and NADH. The Km were 0.47 mM for L-alanine, 0.16 mM for NAD+, 0.22 mM for pyruvate, 0.067 mM for NADH, and 66.7 mM for ammonia. The Km for L-alanine was the smallest in the alanine dehydrogenases studied so far. The enzyme gene was cloned into Escherichia coli JM109 cells and the nucleotides were sequenced. The deduced amino acid sequence was very similar to that of the alanine dehydrogenase from Bacillus subtilis. However, the Enterobacter enzyme has no cysteine residue. In this respect, the Enterobacter enzyme is different from other alanine dehydrogenases.     

Purification and properties of beta-N-Acetylhexosaminidase from cabbage

beta-N-Acetylhexosaminidase was purified from the extract of cabbage by sequential steps of ammonium sulfate fractionation, chromatofocusing, DEAE-Sepharose CL-6B ion exchange chromatography and Sephacryl S-200 HR gel filtration. By these steps, the purity of the enzyme increased by 256 fold with a recovery of 8%. The purified enzyme was homogeneous as examined by native PAGE. It showed an optimal pH of 4, an optimal temperature of 60 degrees C and a Km of 0.94 mM for hydrolysis of pNp-beta-GlcNAc. The molecular mass of the enzyme determined from filtration through Sephacryl S-200 was 150 kDa. Three subunits with molecular mass of 64, 57 and 51 kDa were observed as determined by SDS-PAGE. NBS (0.025 mM), DEPC (3 mM) and WRK (30 mM) significantly inhibited the activity of the enzyme. The enzyme also showed activity toward pNp-beta-GalNAc, N,N'-diacetylchitobiose, N,N',N"-triacetylchitotriose and N,N',N",N"'-tetraacetyl chitotetraose but showed no activity toward pNp-alpha-GlcNAc, chitin and ethylene glycol chitin.     

Macrophage migration inhibitory factor expression in human renal allograft rejection

BACKGROUND: Macrophage migration inhibitory factor (MIF) plays a pivotal role in immune-mediated diseases. Despite the long-standing association of MIF with the delayed-type hypersensitivity response, the potential role of MIF in allograft rejection is unknown. METHODS: MIF expression was assessed by in situ hybridization and immunohistochemistry staining in 62 biopsies of human renal allograft rejection and in normal human kidney. RESULTS: MIF mRNA and protein is constitutively expressed in normal kidney, being largely restricted to tubular epithelial cells, some glomerular epithelial cells, and vascular smooth muscle cells. In both acute and chronic renal allograft rejection, there was marked up-regulation of MIF mRNA and protein expression by intrinsic kidney cells such as tubular epithelial cells and vascular endothelial and smooth muscle cells. There was also MIF expression by infiltrating macrophages and T cells. Of note, macrophage and T cell infiltrates were largely restricted to areas with marked up-regulation of MIF expression, potentially contributing to the development of severe tubulitis and intimal or transmural arteritis. Quantitative analysis found that increased MIF expression in allograft rejection gave a highly significant correlation with macrophage and T cell accumulation in both the glomerulus and interstitium (P<0.001). In addition, the number of MIF+ tubules and interstitial MIF+ cells correlated significantly with the severity of allograft rejection (P<0.01), and the loss of renal function (P<0.01). In contrast, no up-regulation of renal MIF expression and no leukocyte accumulation was seen in allograft biopsies without evidence of rejection. CONCLUSIONS: This is the first study to demonstrate that local MIF expression is up-regulated during allograft rejection. The association between up-regulation of MIF expression, macrophage and T cell infiltration and the severity of renal allograft rejection suggests that MIF may be an important mediator in the process of allograft rejection.     

Electroconvulsive shock does not induce c-fos and junB, but TIS1 and TIS8/zif-268, in neonatal rat hippocampus

Insular neurons responsive to baroreceptor challenge have been identified in the rat, but not previously in primates. Characterization of baroreceptor-related neurons was performed in 15 anesthetized monkeys (Macaca fascicularis) using extracellular single-unit recording techniques. 131 units were investigated within the insula and surrounding regions. Based on their responses to phenylephrine hydrochloride (PE) and sodium nitroprusside (SNP), three types of units were distinguished: 35/131 (27%) sympathoexcitatory (SE), 12/131 (9%) sympathoinhibitory (SI) and 84 (64%) null units. More baroreceptive units were found within the insula (38/73, 52%) than in surrounding areas (9/58, 16%) (p < 0.001). Lateralization was indicated with more baroreceptive units being encountered within the right insula (28/44, 64%) than the left (10/29, 34%) (p = 0.02). The majority of the responsive units were located within the dysgranular and granular insula in layers II, III and V/VI. These data suggest that cardiovascular representation may occur in the primate insula as has been shown in other species.     

Long-term follow-up of cranial bone graft in dorsal nasal augmentation

A follow-up of 363 cranial bone grafts for nasal reconstruction is presented. The main indications for the surgery were congenital, posttraumatic, or postrhinoplasty deformity. The results were satisfactory in the vast majority of cases. The complications associated with the grafts and with the donor site are discussed, as are the methods to treat and prevent these complications from occurring.     

Giant-cell interstitial pneumonia in a gas station worker

Giant-cell interstitial Pneumonia (GIP) is a very uncommon respiratory disease. The majority of cases of GIP are caused by exposure to cobalt, tungsten and other hard metals. In this report, we describe GIP in a patient who worked in gas station and dealt in propane gas vessels. He presented with clinical features of chronic interstitial lung disease and underwent an open lung biopsy that showed DIP-like reaction with large numbers of intra-alveolar macrophages and numerous large, multinucleated histiocytes which were admixed with the macrophages. Analysis of lung tissue for hard metals was done. Cobalt was the main component of detected hard metals. Corticosteroid therapy was started and he recovered fully.