Occurrence and formation potential of N-nitrosodimethylamine in ground water and river water in Tokyo

N-nitrosodimethylamine (NDMA), a disinfection byproduct of water and wastewater treatment processes, is a potent carcinogen. We investigated its occurrence and the potential for its formation by chlorination (NDMA-FP_2Cl) and by chloramination (NDMA-FP_2NHCl) in ground water and river water in Tokyo. To characterize NDMA precursors, we revealed their molecular weight distributions in ground water and river water. We collected 23 ground water and 18 river water samples and analyzed NDMA by liquid chromatography-tandem mass spectrometry. NDMA-FP_2Cl was evaluated by chlorinating water samples with free chlorine for 24 h at pH 7.0 while residual free chlorine was kept at 1.0-2.0 mgCl₂/L. NDMA-FP_2NHCl was evaluated by dosing water samples with monochloramine at 140 mgCl₂/L for 10 days at pH 6.8. NDMA precursors and dissolved organic carbon (DOC) were fractionated by filtration through 30-, 3-, and 0.5 kDa membranes. NDMA concentrations were <0.5-5.2 ng/L (median: 0.9 ng/L) in ground water and <0.5-3.4 ng/L (2.2 ng/L) in river water. NDMA concentrations in ground water were slightly lower than or comparable to those in river water. Concentrations of NDMA-FP_2Cl were not much higher than concentrations of NDMA except in samples containing high concentrations of NH₃ and NDMA precursors. The increased NDMA was possibly caused by reactions between NDMA precursors and monochloramine unintentionally formed by the reaction between free chlorine and NH₃ in the samples. NDMA precursors ranged from 4 to 84 ng-NDMA eq./L in ground water and from 11 to 185 ng-NDMA eq./L in river water. Those in ground water were significantly lower than those in river water, suggesting that NDMA precursors were biodegraded, adsorbed, or volatilized during infiltration. The molecular weight of NDMA precursors in river water was dominant in the <0.5 kDa fraction, followed by 0.5-3 kDa. However, their distribution was inconsistent in ground water: one was dominant in the <0.5 kDa fraction, and the other in 0.5-3 kDa. Molecular weight distributions of NDMA precursors were very different from those of DOC. This is the first study to reveal the widespread occurrence and characterization of NDMA precursors in ground water.     

Specific IgA and IgG antibodies to house dust mite Dermatophagoides farinae in nasal secretions

As far as we know, IgA and IgG antibodies to purified house dust mite allergens Der fI and Der fII in nasal secretions have never been documented. Therefore, we determined specific IgA, SIgA and IgG antibodies (abs) to crude extract of D. farinae and its purified allergens Der fI and der f II in nasal secretions collected by aspiration from 34 normal subjects, 25 untreated nasal allergic patients and 28 treated nasal allergic patients on parenteral immunotherapy by means of an avidin-biotin ELISA. The following results were obtained. (1) The specific IgA, SIgA and IgG abs to each of the three kinds of allergens correlated with each other. The groups of patients with nasal allergy (both treated and untreated) showed higher levels of specific IgA, SIgA and IgG abs to the allergens than the normal group. (2) In the group of treated patients, the levels of specific abs were not correlated with the clinical improvement of symptoms or the degree of response to nasal challenge. (3) The treated patients failed to show significantly higher levels of abs in nasal secretions than the untreated patients. (4) The specific IgA and SIgA abs in nasal secretions seemed to be predominantly produced locally, and IgG abs might be transudated from the circulation.     

A mesenchymal malignant mesothelioma that changed from mixed type to purely sarcomatous type]

STUDY OBJECTIVE: To evaluate the long-term efficacy of laparoscopic Burch urethropexy. DESIGN: Pilot study. SETTING: Private practice. PATIENTS: Thirty-five consecutive women (average age 45.5 yrs, average parity 2.3, average weight 67.7 kg) treated for genuine stress incontinence between May 1992 and July 1994. INTERVENTIONS: Urethropexy was performed with curved needle suturing in 7 women, straight needle suturing in 5, and Stamey needle suturing in 23. Twenty-five (71.4%) patients had concomitant pelvic surgery. MEASUREMENTS AND MAIN RESULTS: Wilcoxon two-sample, chi2, and Fisher's exact tests were performed to determine which variables were significantly associated with surgical success. Average operating time was 190 minutes, hospitalization 24 hours, and catheterization 5 days. The cure rate of stress incontinence was 89% 3 months and 86% 1 year after surgery. At average follow-up of 34 months, only 68.6% of patients reported complete or almost complete cure, 11.4% were improved, and 20% were complete failures. The only operative variable approaching statistical significance for predicting surgical success was type of suture needle (p = 0.07), with the Stamey needle group having the highest cure rate. Women who were cured or almost cured had a significantly shorter follow-up than those who were improved or failures (p = 0.001). CONCLUSION: The success rate of laparoscopic Burch urethropexy compares with that of open Burch procedure at 1 year, but drops considerably thereafter.     

Analysis of atmospheric electric field variation signals using digital natural observation method

As the atmospheric electric field always fluctuates, its observed waveforms are very complicated. It is important to detect the characteristic variation from the observed signals and determine its cause. The natural observation method is adequate for analyzing such nonperiodic signals as the atmospheric electric field signals. In this method the aspectum is proposed as the quantity to estimate the instantaneous power. In this study signal processing by the aspectum was applied to signals of atmospheric electric field variation. It was clarified that a strong correlation exists between the instantaneous fluctuations of atmospheric electric field and the wind speed in the convenient meteorological environment. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(1): 27–34, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20302     

Electrostatic Field Variation in the Atmosphere Induced by Earth Potential Difference Variation During Seismic Wave Propagation

To clarify the relationship between earthquakes and electrical phenomena, signals of three parameters were observed continuously at Sennan in Akita Prefecture, Japan: ground acceleration (GAC), earth potential difference (EPD), and electrostatic field in the atmosphere (EFA). A large metal plate was used as an electrostatic antenna to observe EFA variation. For this paper, we used the digital natural observation (D-NOB) method as a signal processing technique and found clear EPD and EFA waveforms during seismic wave propagation. Our observation and examination results show that GAC causes EPD variation. Subsequently, the EPD variation induces EFA variation     

A Goal-Dependent Abstraction for Legal Reasoning by Analogy

This paper presents a new algorithm to find an appropriate similarityunder which we apply legal rules analogically. Since there may exist a lotof similarities between the premises of rule and a case in inquiry, we haveto select an appropriate similarity that is relevant to both thelegal rule and a top goal of our legal reasoning. For this purpose, a newcriterion to distinguish the appropriate similarities from the others isproposed and tested. The criterion is based on Goal-DependentAbstraction (GDA) to select a similarity such that an abstraction basedon the similarity never loses the necessary information to prove the ground (purpose of legislation) of the legal rule. In order to cope withour huge space of similarities, our GDA algorithm uses some constraintsto prune useless similarities.     

Partial discharge characteristics of inverter-fed motor coil samples under ac and surge voltage conditions

This work investigates the partial discharge (PD) characteristics of twisted pair samples for inverter-fed motor coil under ac and surge voltage conditions. It also discusses the difference in the PD inception characteristics of a twisted pair under 60-Hz voltage and surge voltages with a steep wave front. The PDIV under ac voltage was measured and was found to agree well with the theoretical value using electric field analysis and Paschen's law. The PDIV under surge voltage was measured for different repetition rates and the PDIV for 60-pps repetition was found to be lower than those for 6 pps and for the single shot, which suggested that the electrical insulation performance would be influenced by the repetition rate. The PDIV under surge voltages was 1.5 to 1.8 and 2.3 to 2.7 times higher than those under AC voltage application for the used and virgin samples, respectively.     

Eighteen novel human genes regionally mapped on chromosome 11

The list of LDL receptor superfamily relatives is still growing. The two most recently discovered family branches are (1) a set of receptors characterized by expression in brain and a very close relationship to the LDL and VLDL receptors, and (2) highly cross-species (man, mouse, rabbit, chicken) conserved complex mosaic receptors which contain structural domains so far not found in the superfamily. At present, we know very little about the physiological function(s) of these molecules. They can be safely assumed, based on the presence of seven, eight or 11 clustered LDL receptor ligand binding repeats, to recognize mammalian apolipoprotein E but, based on the absence of apolipoprotein E in birds, they may exhibit interactions quite different from and/or in addition to typical lipoprotein receptors in vivo.     

ITU-T standardization of audiovisual communication systems in ATMand LAN environments

This paper presents the ITU-T Study Group 15 development of H-series Recommendations that allow interworking between different audiovisual communication terminals manufactured by different equipment providers. The paper focuses on H.310 and H.321 systems for broad-band ATM environments and H.322 and H.323 systems for LAN environments where the quality of service may or may not be guaranteed. The paper first lists the Recommendations developed by the ITU-T for audiovisual communication systems and the network environments in which they may be used. It then describes the design philosophy, the network specific characteristics, and hardware trials for each system. Then it describes the communication control protocol defined in H.245 which is used commonly by different audiovisual communication systems. Finally, the paper discusses interworking scenarios for communication between the different types of terminal on different networks