Mine detection using scattering parameters

The detection and disposal of antipersonnel land mines is one of the most difficult and intractable problems faced in ground conflict. This paper presents detection methods which use a separated-aperture microwave sensor and an artificial neural network pattern classifier. Several data-specific preprocessing methods are developed to enhance neural network learning. In addition, a generalized Karhunen-Loeve transform and the eigenspace separation transform are used to perform data reduction and reduce network complexity. Highly favorable results have been obtained using the above methods in conjunction with a feedforward neural network.     

The skin injury induced by high energy dose of ultraviolet in hairless descendants of Mexican hairless dogs

In a primary cell culture system of fetal rat brain, the calmodulin-dependent protein-kinase IV (CaMKIV) could be induced by the thyroid hormone T3 in a time- and concentration-dependent manner, provided the tissue was excised not later than day 15 of gestation (E15) (Krebs et al., J. Biol. Chem. 271, 11055, 1996). We report here that in the fetal thymus CaMKIV could not be detected earlier than day 16 of gestation and that the expression of this enzyme was fully upregulated at day 18. In mouse fetal thymus organ culture (FTOC) of day 14 embryonic thymus, CaMKIV could not be detected, even after several days of culture if a minimal culture medium lacking fetal calf serum was used. However, after addition of fetal calf serum to the culture medium the expression of CaMKIV could be specifically induced. Furthermore, it could also be shown that during T-cell development in the adult murine thymus the expression of CaMKIV was tightly regulated. Taken together, these results demonstrate that the expression of CaMKIV, an enzyme involved in the regulation of Ca(2+)-dependent gene expression, is itself under stringent regulatory control during tissue development.     

Microstructure of the interface in magnesium alloy to aluminium alloy dissimilar joints produced by friction stir welding

Friction stir welding (FSW) is a process that was developed by the UK Welding Institute (TWI) in 1991.¹ Because of its status as a solid-phase joining process operating at a temperature below the melting point of the materials being joined, FSW usually generates less residual stress than fusion welding, being also advantageously free from fume, porosity, and solidification cracking. The mechanical properties of welds are equivalent or superior to those of conventional welds and offer a high level of reliability. Other merits of FSW include relatively low equipment costs, low operating costs, and no required training. For this reason, in the decade or so since the principle of FSW was invented, the process has seen a number of practical applications in railway and ship structures as well as for rocket fuel tanks in the aerospace field² and continues to draw considerable attention by the engineering industry worldwide. The foregoing applications, however, all refer to components produced from aluminium alloys.     

Effect of training program based on anaerobic threshold in the early phase after acute myocardial infarction

We devised a new physical training program on the basis of anaerobic threshold for rehabilitation in the early phase of acute myocardial infarction. Forty-four patients were divided into two groups, control and training. We measured the left ventricular ejection fraction using nuclear stethoscopy during the treadmill test and calculating radioactive cardiac output. In the training group, anaerobic threshold and exercise time to the anaerobic threshold point were significantly increased, and stroke volume at rest measured by the dye dilution method increased significantly. Radioactive cardiac output during exercise also increased after the exercise therapy. These results indicate that the rehabilitation program consisting of physical training based on the anaerobic threshold is effective.     

Immunohistochemically detected expression of motility-related protein-1 (MRP-1/CD9) in lung adenocarcinoma and its relation to prognosis

STUDY OBJECTIVE: To determine the effect of adding the nebulized anticholinergic drug ipratropium bromide to standard therapy compared with standard therapy alone for acute severe asthma (peak expiratory flow rate [PEFR] < 50% of predicted) in children presenting to the emergency department. METHODS: Ninety children aged 6 to 18 years were randomly assigned to two groups in a prospective, double-blind, placebo-controlled study performed in the ED of an urban children's hospital. All children received nebulized albuterol solution (.15 mg/kg) every 30 minutes, and all received oral steroids with the second dose of albuterol. Children in group 1 received ipratropium bromide (500 micrograms/dose) with the first and third dose of albuterol those in group 2 received saline placebo instead of ipratropium. Pulmonary functions (PEFR and 1-second forced expiratory volume [FEV1]) and physiologic measurements were assessed every 30 minutes up to 120 minutes. By chance, the baseline values for percent of predicted PEFR and FEV1 differed between the two groups. Therefore a multivariate model accounting for both time and baseline effects was used to compare the response between groups. RESULTS: On average, and adjusting for baseline measures, children in the ipratropium group had a significantly greater improvement in percent of predicted PEFR than did children in the placebo group at 60 minutes (P = .02), 90 minutes (P = .002), and 120 minutes (P < .0001). The improvement in percent predicted FEV1 was significantly greater for children in the ipratropium group only at 120 minutes (P = .013). Nine children (20%) from the ipratropium group and 14 (31.1%) from the control group were admitted (P = .33, chi 2). There were no significant adverse effects attributable to the ipratropium, and there was no relation between ipratropium use and changes in pulse, respiratory rate, blood pressure, or oxygen saturation. CONCLUSION: We detected significant improvement in pulmonary function studies over 120 minutes in children with severe asthma who were given nebulized ipratropium combined with albuterol and oral steroids, compared with children who received the standard therapy. Further study is needed to determine whether early use of ipratropium decreases the need for hospitalization.     

Induction of granulomas in interferon-gamma gene-disrupted mice by avirulent but not by virulent strains of Mycobacterium tuberculosis

Tumor necrosis factor-alpha (TNF-alpha) levels were measured in the serum (sTNF-alpha) or bone marrow (BM) biopsies of 43 patients with myelodysplastic syndromes (MDS) who subsequently received therapy with a combination of pentoxifylline and ciprofloxacin (PC) with or without dexamethasone (PCD). All 43 patients received only PC therapy for 12 weeks, after which 18 of 36 nonresponders received PCD. A total of 18 of 43 patients showed a hematologic or cytogenetic response or both. BM TNF-alpha levels were semiquantitatively assessed using immunohistochemistry on a scale of 0-8+ and in the serum using enzyme linked immunoassay. The median TNF-alpha for the entire group was 3.0 in BM and 6.9 pg/ml in the serum, and 14 patients had no detectable levels. Responders had higher BM levels (median 3.5 vs. 2.0) than nonresponders, although this was not statistically significant. During PC therapy, a decline in BM TNF-alpha level was seen in the entire group, which was significant at 2 weeks (p = 0.02), 8 weeks (p = 0.001), and 12 weeks (p = 0.0001). Both responders (p = 0.01) and nonresponders (p = 0.03) had a decline at 8 weeks, but at 12 weeks, only the responders continued to show a significant decline (p = 0.03). We conclude that MDS patients with high BM TNF-alpa levels have a better chance of responding to PCD therapy and that the therapy is quite successful in reducing the TNF-alpha levels in a sustained fashion. Future studies need to be directed at identifying agents that would be more potent suppressors of the proapoptotic cytokines in these patients.     

DNA cleaving activities of 9-membered masked enediyne analogues possessing DNA intercalator and sugar moieties

The DNA cleaving properties of various enediyne analogues possessing sugar moieties and DNA-intercalators were investigated. The DNA cleaving experiments show that these hybrids analogues induced sequence-selective DNA cleavage and the simple sugars in the enediyne serve as a DNA recognition element for DNA cleavage.     

5-Azacytidine induces toxicity in PC12 cells by apoptosis

5-Azacytidine (5 Az)is a potent inhibitor of DNA methylation, and it may allow inactive genes to become expressed. In a previous study, we demonstrated that 5 Az administered to the dam induced apoptosis in the brains of fetal mice. In this study, the 5 Az-induced apoptosis was further characterized in differentiated PC 12 cells as a model for neuronal apoptosis. Cell death, determined by the activity of released lactate dehydrogenase (LDH) into the medium, occurred from 24 to 48 hrs after 5 Az treatment. Toxicity for differentiated PC 12 cells was observed on treatment with more than 10(-1) micrograms/ml of 5 Az, and it reached the maximal level at 10 micrograms/ml. Cycloheximide, an inhibitor of protein synthesis, prevented 5 Az toxicity, suggesting that this cell death required protein synthesis which could be related to the activation of a dormant gene(s). Electrophoresis of DNA from 5 Az-treated cells evoked ladder formation, indicating the cleavage of DNA into nucleosomes. Scanning electron microscopy demonstrated bleb formation, the so-called apoptotic bodies on the cell surface. The biochemical and morphological findings indicated that 5 Az-induced cell death occurred in the form of apoptosis. 5 Az-induced cell death was prevented by treatment with cAMP but not by treatment with high K+ or deoxycytidine. These results suggest that a cAMP-sensitive mechanism is involved in 5 Az-induced cell death. PC 12 cells should be of value in elucidating the molecular mechanism of 5 Az-induced neuronal apoptosis.     

Effects of siRNAs targeting the spacer sequence of plant RNAi vectors on the specificity and efficiency of RNAi

Small interfering RNAs (siRNAs) generated from the spacer region of hairpin RNAs were not detected in the RNA interference (RNAi) plants targeting the fatty acid desaturase gene. The expression of the desaturase gene was stably suppressed even when siRNAs targeting the spacer sequences were introduced into this plant.     

Changes in volatile flavour components of soybeans during roasting

Volatile concentrates were prepared from whole soybeans, roasted at 200°C for 10, 20 and 30 min, by steam distillation under reduced pressure followed by ether extraction, and analysed by gas chromatography and gas chromatography-mass spectrometry, in comparison with the volatile concentrate from raw soybean flour.Major flavour components of raw soybean, such as n-hexanol, 1-octen-3-ol and n-hexanal, decreased during the course of roasting, but the rate of this decrease was not rapid, especially between 10 and 20 minutes' roasting. During the roasting period, alkylated pyrazines, oxygenated furans, oxygenated pyrroles and phenols were formed or increased markedly. On the other hand, sensory evaluation showed that a flavour change to ‘desirable’ from ‘beany’ or ‘objectionable’ occurred between 10 and 20 minutes' roasting. These results suggest that roast flavour masks the ‘beany’ flavour in soybean.