Ongoing Laboratory Performance Study on Chemical Analysis of Hydrophobic and Hydrophilic Compounds in Three Aquatic Passive Samplers

The quality of chemical analysis is an important aspect of passive sampling-based environmental assessments. The present study reports on a proficiency testing program for the chemical analysis of hydrophobic organic compounds in silicone and low-density polyethylene (LDPE) passive samplers and hydrophilic compounds in polar organic chemical integrative samplers. The median between-laboratory coefficients of variation (CVs) of hydrophobic compound concentrations in the polymer phase were 33% (silicone) and 38% (LDPE), similar to the CVs obtained in four earlier rounds of this program. The median CV over all rounds was 32%. Much higher variabilities were observed for hydrophilic compound concentrations in the sorbent: 50% for the untransformed data and a factor of 1.6 after log transformation. Limiting the data to the best performing laboratories did not result in less variability. Data quality for hydrophilic compounds was only weakly related to the use of structurally identical internal standards and was unrelated to the choice of extraction solvent and extraction time. Standard deviations of the aqueous concentration estimates for hydrophobic compound sampling by the best performing laboratories were 0.21 log units for silicone and 0.27 log units for LDPE (factors of 1.6 to 1.9). The implications are that proficiency testing programs may give more realistic estimates of uncertainties in chemical analysis than within-laboratory quality control programs and that these high uncertainties should be taken into account in environmental assessments.

Development of a safety analysis method for volatile organic compounds using 2-phenoxyethanol as solvent

Indoor volatile organic compounds (VOCs) are usually sampled using active carbon samplers and subsequently analyzed using gas chromatography-mass spectrometry (GC-MS) to assess the exposure risk to workers. Therefore, selection of a suitable solvent for VOC extraction is crucial. However, reports on the use of 2-phenoxyethanol-known for its low vapor pressure and low toxicity-as a solvent for extracting VOCs from activated carbon are lacking. Here, we show that 2-phenoxyethanol is a suitable alternative solvent with low toxicity and can extract a wide variety of VOCs without overlapping with target VOCs on the gas chromatogram. The recoveries of 2-phenoxyethanol were 57% (styrene) to 83% (methyl n-butyl ketone), which were higher than those of CS2, acetone, and n-hexane at room temperature. The recoveries improved to 67% (styrene) to 102% (isopentyl acetate) under 50 °C. Optimization of the GC conditions showed that a viscosity delay time of 3 s was required to avoid producing bubbles in the injection syringes. We selected DB-HeavyWAX as a column because it could be heated above the boiling point of 2-phenoxyethanol (247 °C), allowing the removal of 2-phenoxyethanol from the column. This study contributes to the development of analysis methods for VOCs under safe operating conditions.

Development of an analytical method for indoor polycyclic aromatic hydrocarbons and their halogenated derivatives by using thermal separation probe coupled to gas chromatography-tandem mass spectrometry

Polycyclic aromatic hydrocarbons (PAHs) and their halogenated derivatives (XPAHs) have been a concern because of their high toxicity. Monitoring indoor PAHs and XPAHs concentrations is important for risk assessment because humans typically spend >90 % of their time indoors. However, the background levels of indoor PAHs and XPAHs concentrations are unknown because of the low sensitivity of conventional analytical methods. In this study, we developed a highly sensitive analytical method using a thermal separation probe (TSP) coupled to a gas chromatograph with a triple quadrupole mass spectrometer method for 26 PAHs and 40 XPAHs. The method quantification limit (MQL) values of the TSP method were 1.1 (3,8-dichlorofluoranthene)-906 (dibenzo[a,e]pyrene) times lower than those of the conventional method. The regression line comparing the TSP and conventional methods was y = (0.944 ± 0.0401)x, which was in good agreement. These results demonstrate that the TSP method can be applied to indoor air analysis. The total concentrations of PAHs and XPAHs were 944 and 73.5 pg m-3 for the house and 735 and 0.924 pg m-3 in the office, respectively. Among the detected compounds, 13 PAHs and XPAHs could not be detected using conventional methods because of their high MQL values. The composition of total toxicity equivalency values in the house was dominated by dibenzo[a,i]pyrene (DBaiP: 43.2 %) and dibenzo[a,h]pyrene (DBahP: 27.1 %), which could not be detected using the conventional method. Therefore, the TSP method can improve the risk assessment of indoor PAHs and XPAHs.

Enhancement of photodegradation of polyethylene with adsorbed polycyclic aromatic hydrocarbons under artificial sunlight irradiation

The photodegradation of plastic waste produces microplastics (MPs) in marine environments. Plastics can adsorb hydrophobic organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) and can be transported over long distances. However, the impact of adsorbed pollutants on the photodegradation remains unknown. Here, we show that adsorbed PAHs act as photocatalysts that promote the photodegradation of polyethylene. Upon light irradiation, coloration and surface degradation of the PAH-adsorbed polyethylene sheets were observed, indicating that the PAH-adsorbed polyethylene sheets are less resistant to light. Furthermore, fluorene, phenanthrene, anthracene, benzo[a]anthracene, benzo[a]pyrene, and indeno[1,2,3-cd]perylene adsorbed on polyethylene MP exhibited lower photodegradation rates than the aqueous phase. These results indicate that these PAHs can act as photocatalysts; their role of PAHs may have two adverse effects on marine environment. First, enhanced photodegradation of plastic waste increased the production of MPs. Second, the lifetime of PAHs is extended, thereby enhancing PAHs pollution in marine environments.

Spatiotemporal distribution and pollution assessment of trace metals in the Buriganga River, Bangladesh

The Buriganga River plays a key role in the socioeconomic structure of Dhaka, the capital of Bangladesh. However, this river is severely polluted and is considered one of the most polluted in the world. Therefore, this study aimed to assess the concentrations of various metals in the Buriganga River. A study was conducted from August 2019 to February 2020 to determine the concentrations of 16 metals in water samples (n = 210) collected from 10 distinct sites in the Buriganga River. The mean values for the concentrations of Cr, Mn, Ni, Zn, As, Se, Cd, Sb, and Pb in river water were above the guideline values prescribed by the WHO, Japan, and Bangladesh. Moreover, the fraction ratios of Be, Cr, Co, Ni, Cu, Zn, Se, Mo, Ag, Cd, Sb, and Pb were high (>0.85); consequently, these metals could accumulate at high concentrations in river sediments. Assessment using the single-factor pollution index allowed the classification of the pollution level as 'serious pollution' for Sb and 'heavy pollution' for Cd, Ni, and Pb. The trace metal concentrations in this river imply that crops cultivated along the river using river water may also be contaminated with trace metals.

Development of a New Polar Organic Chemical Integrative Sampler for 1,4-dioxane Using Silicone Membrane as a Diffusion Barrier

Efficient monitoring methods must be developed for 1,4-dioxane, which is suspected to be carcinogenic to humans and is highly mobile in aquatic environments. In this regard, polar organic chemical integrative samplers (POCIS) have been utilized extensively as passive samplers for determining time-weighted average concentrations of hydrophilic organic compounds. However, POCIS are difficult to apply to extremely hydrophilic known organic compounds with negative log octanol-water partition coefficient (K_ow ) values due to their limited kinetic sampling time. Using an activated carbon-based sorbent with a high adsorption capacity and a bilayer of silicone and polyethersulfone membranes that inhibit mass transfer to the sorbent, we developed a POCIS device to measure 1,4-dioxane (log K_ow -0.27) in the present study. Permeation and field calibration tests demonstrated that the use of silicone membranes effectively reduces the water-to-sorbent mass transfer rate. The sampling rate and kinetic sampling period determined by field calibration tests were 1.4 ml day^-1 and >14 days, respectively. Finally, the developed POCIS device was applied to a landfill treatment plant to determine the 1,4-dioxane concentrations. Environ Toxicol Chem 2023;42:296-302. © 2022 SETAC.

Comparative Evaluation of the Polar Organic Chemical Integrative Sampler in Two Types of Validation Systems Simulating Peak Concentration Events

Polar organic chemical integrative sampler (POCIS) devices have been suggested for measuring time-weighted averages (TWAs) of contaminant concentrations resulting from chemical leak accidents in aquatic environments. However, the response of the POCIS device in the emergency condition in natural water remains unclear. The response of the POCIS device to contaminant fluctuation was investigated using a chamber test with tap water and a channel test with natural water. The fluctuation in the chamber and the channel simulated the condition of river water under a chemical leak scenario (maximum concentration: 1-10 μg L^-1 , half-life: 1 day). The target chemicals were neonicotinoid pesticides (dinotefuran, clothianidin, thiamethoxam, imidacloprid, acetamiprid, and thiacloprid) and bisphenol A. The ratio of the POCIS measured value to the TWA values of grab samplings (POCIS/TWA) for the channel test (temperature: 15 °C, flow velocity: 15 cm s^-1 ) ranged from 61% (clothianidin) to 133% (thiacloprid). The results indicated that the POCIS device could be effectively used as a monitoring device in an aquatic environment under the chemical leak scenario over a time period of more than14 days. In addition, the POCIS/TWA ratios obtained from the chamber test and the channel test were in the range of 50-150%. Thus, the chamber test could be used to evaluate the POCIS device at a low cost. Environ Toxicol Chem 2021;40:3010-3018. © 2021 SETAC.

Photolysis of polycyclic aromatic hydrocarbons adsorbed on polyethylene microplastics

Contaminants adsorbed on microplastics (MPs) are a potential risk to aquatic environments. Several studies have demonstrated that polycyclic aromatic hydrocarbons (PAHs), which adsorb on MPs, can be photolyzed in aqueous solutions. We investigated photolysis of PAHs on MPs under sunlight conditions to estimate their environmental fate for the first time. The PAHs (25 ng each) were added to polyethylene powder, which was used as the MP sample. The MP sample was agitated in water with sunlight irradiation; thereafter, the concentration of the PAHs on the MP sample was determined by high-pressure liquid chromatography with a fluorescence detector. The half-life values of the PAHs were estimated between 3.4 × 10² (pyrene) and 3.2 × 10⁴ min (benz[j]fluoranthene). These values are 0.5 (fluoranthene) to 25 (benzo[a]pyrene) times larger than those in the aqueous phase. Additionally, the degradation of PAHs by OH radicals produced by the photolysis of nitrate was observed.

Development and Calibration of the Polar Organic Chemical Integrative Sampler (POCIS) for Neonicotinoid Pesticides

Neonicotinoid pesticides are highly hydrophilic systemic insecticides that have been extensively used worldwide. To evaluate their environmental risks, the concentrations of these pesticides in the aquatic environment must be monitored. Although the polar organic chemical integrative sampler (POCIS) has proved to be a suitable passive sampler for many highly hydrophilic compounds, Oasis HLB (Waters) POCIS has shown limitations for the monitoring of neonicotinoid pesticides, such as short linear uptake ranges. In the present study we optimized POCIS for neonicotinoid pesticides by selecting suitable adsorbents and filters. The ENVI-Carb (Supelco) nonporous carbon-based adsorbent demonstrated a good balance between strong sorption and high recovery. Static renewal experiments showed that the our POCIS device using ENVI-Carb with a polyethersulfone membrane filter had a 3 d (dinotefuran) to 28 d (clothianidin, imidacloprid, acetamiprid, and thiacloprid) linear range, which is longer than that of HLB POCIS (≤1 [dinotefuran] to 14 d). The POCIS using ENVI-Carb with a polytetrafluoroethylene membrane had higher sampling rates (0.270 L/d [clothianidin] to 0.686 [imidacloprid] L/d) than those of the HLB POCIS for short-term deployment. The time-weighted average concentrations in actual river water measured by the new POCIS were in good agreement with those obtained by repeated grab sampling, within 30%. Moreover, POCIS detected 2 neonicotinoid pesticides that were not detected by grab sampling. Thus, the proposed POCIS is a promising tool for the monitoring of neonicotinoid pesticides. Environ Toxicol Chem 2020;39:1325-1333. © 2020 SETAC.

Characteristics of ammonia gas and fine particulate ammonium from two distinct urban areas: Osaka, Japan, and Ho Chi Minh City, Vietnam

Continuous and simultaneous measurements of ammonia gas (NH₃) and fine particulate ammonium (PM_2.5NH₄⁺) were performed in two distinct urban areas: Osaka, Japan, and Ho Chi Minh City (HCMC), Vietnam. Measurements were performed using a new online instrument. Two measurement periods were conducted during February 11-March 12, 2015 (cold period), and July 1-September 14, 2015 (warm period), at the urban site in Osaka, while 17 days of measurements, from May 21 to June 8, 2015, were conducted at the urban site in HCMC. The average NH₃ concentration at the HCMC site was much higher than that at the Osaka site. The differences in the NH₃ levels between the two cities are a result of their different emission sources. Traffic emission is a significant contributor to the NH₃ levels within the urban area in Osaka. Conversely, the contribution of traffic emission to the NH₃ levels in the HCMC urban area is negligible. With a population of around 8.5 million people living in the urban area of HCMC, the high NH₃ level is due to human sources and poor waste management systems, especially because of the high temperature (30 °C) and dense population of the city (density up to 42,000 inhabitants per km²). In contrast to the NH₃ levels, the highest PM_2.5NH₄⁺ level occurred during the cold period at the Osaka site, and the average level at this site was higher than that at the HCMC site. The availability of atmospheric acids, low temperature, and high humidity facilitates the formation of ammonium. Our results indicate that NH₃ plays a key role in secondary inorganic aerosol formation; therefore, it contributes to a significant amount of PM_2.5 at the Osaka site. In contrast, the high levels of PM_2.5 observed at the HCMC site are likely from road traffic emission, mainly motorcycles, rather than secondary inorganic aerosol formation.

Isolation of a new mixed valence Pt molecular oxide using phosphine as protecting group

A novel tetranuclear mixed valence cationic Pt molecular oxide [((Me3P)2Pt)3Pt(OH)6]4+ is obtained by reacting H2Pt(OH)6 and (Me3P)2Pt2+, whose NMR spectra suggest the existence of another species in solution that may serve as a starting point for further synthesis of Pt molecular oxides.

[Bowel perforation after extracorporeal shock wave lithotripsy: a case report]

A case of intestinal perforation caused by ESWL for left ureteral calculus is reported. A 69-year-old male underwent the graft replacement for bilateral iliac aneurysm in March, 1996. In February, 1999, there appeared left flank pain, and a diagnosis of left ureterolithiasis was made by radiological examination. On March 29 he was admitted to our department for ESWL. On March 30, ESWL for calculus in the pelvic region was performed with the patient in the prone position. The patient complained of the left lower abdominal pain immediately after ESWL, but no muscular defense was observed. Since the pain was not relieved, CT was performed on March 31, but no evident abnormal finding was found. Thereafter the pain continued and on April 2 muscular defense was also noted. On CT performed a second time, free air and evidence of ileus were found, so emergency operation was performed. Two perforations about 2 mm in size were found in the jejunum 130 cm from the Treitz' ligament, which led to diagnosis of intestinal perforation due to ESWL. The patient followed a satisfactory postoperative course and was discharged on April 23. There has been only one reported case of intestinal perforation due to ESWL. It is a very rare complication. However, this complication should be taken into consideration where the patient has the history of abdominal surgery and where ESWL was performed with the patient in the prone position.

Research on pelvic angle variation when using a pelvic support

A pelvic support consisting of a forward sloping wedge of foam has been tested as an addition to conventional office seating for VDT work. In experiment 1 a questionnaire investigation was carried out on the impressions of 10 male and 10 female subjects who sat using pelvic supports. A general result from the questionnaire was that the waist and pelvis were felt to be stable and the evaluation was more positive with the support than without. In experiment 2, pelvis and chest inclinations were measured during sitting with and without the pelvic support. Over a long work period, significant differences were not observed. In both cases, subjects were able to move freely and there were no significant changes in posture. In experiment 3, pelvis and chest inclinations were measured in conditions of no pelvic support and with supports of 10, 20 and 30 degrees. The experiment demonstrated that a support angle of 10 degrees was stable and comfortable. In this research, it was found that the change of inclination of the pelvis can be measured continuously using an angle of inclination sensor. Imposing a forward slope of 4 to 10 degrees on the seat pan surface using the pelvic support had a positive effect, while angles of 20 and 30 degrees had a negative effect.

Adenoviral E1A-associated protein p300 is involved in acute myeloid leukemia with t(11;22)(q23;q13)

p300, which was originally cloned as a nuclear binding target of the adenovirus E1A oncoprotein, forms a family with cyclic-AMP response element binding protein (CREB)-binding protein (CBP). p300/CBP are considered to be transcriptional coactivators that connect the basal transcriptional machinery to various DNA-binding transcriptional factors. p300/CBP are implicated in both cell differentiation and regulation of cell-cycle. We identify here that the p300 gene is fused to the MLL gene and that in-frame MLL-p300 fusion protein is generated in acute myeloid leukemia (AML) with t(11; 22)(q23; q13). These findings suggest that the basis for the leukemogenesis of t(11; 22)-AML is the inability of p300 to regulate cell-cycle and cell differentiation after fusion with MLL.

Performance of 3-D digitizing in stereoscopic images

Experiments were conducted to understand the basic characteristics of pointing to three-dimensional images generated by stereoscopic images. The experimental examination found that it was difficult to point to the correct position of the image and that the depth of the image was underestimated so that the object perceived by the subject was distorted. Subjects who were familiar with viewing 3-D images made less error in position and size perception than did subjects having little experience in viewing 3-D images. These results imply that the performance of 3-D pointing in stereoscopic 3-D images will improve with experience although it is difficult to perform a 3-D pointing precisely.

Psychological effect of stereoscopic 3-D images with fragrances

Stereoscopic 3-D images are used with a lot of virtual reality systems because of their sense of reality. At the same time, in the training that heightens levels of self control of autonomic responses with images, it is thought that reality of software is important. Therefore, the authors investigated use of 3-D images as a technical tool to heighten the reality of software. In this study, a laboratory was transformed into a relaxation room using 3-D images with fragrances and an experiment was carried out to examine the psychological effect of it. From the results of this study, the authors reported on the effects of fragrances on psychological responses when viewing 3-D images and the possibilities of producing these effects for relaxation.

Surmised state of accommodation to stereoscopic three-dimensional images with binocular disparity

Three-dimensional image (3-D image) was experimentally generated by the binocular disparity principle, and psychological tests were performed in relation to the state of accommodation. An image of a square formed by the time-sharing system using liquid crystal (LC) shutter glasses was displayed before the CRT screen (forward image) by the crossed visual-line method and behind the monitor screen (backward image) by the non-crossed visual-line method. The subjects were requested to subjectively compare each image with the original image on the CRT screen in relation to the size. The forward image displayed by the crossed visual lines looked smaller than the original image, while the backward image displayed by the non-crossed visual lines looked larger. In consideration of the developmental mechanism of micropsia occurring in patients with accommodative palsy or paresis of accommodation and macropsia occurring in patients with accomodative spasm, it was surmised that, in the generation of 3-D image due to binocular disparity, accommodation works so that the original image position is maintained.

A study on visual characteristics of binocular 3-D images

To put the binocular 3-D image system into practical use, it is necessary to investigate the relationship between the system and human subjects in order to make an ergonomic evaluation of the system. In this study, a comparative analysis is made of the changes in the accommodation and pupil functions before and after observing binocular 3-D images as the visual distance varies. The results suggest that: (1) the discordance in the distance information on the accommodation and pupil functions when observing 3-D images is compensated by the miosis and altering the focal depth, (2) from the consideration of the effect of the visual distance condition on the visual functions, it is believed that the visual functions are stabilized at the dark focus in the sense that the changes in the contraction and relaxation after observing the 3-D images are minimized.

The development of a dummy head for 3-D audiovisual recording for transmitting telepresence

Manufacturing systems that employ modern technology often deprive workers of their humanity. One such example is seen in teleconferencing between remote plants. Here, it is difficult for participants to make eye-to-eye contact, a major obstacle in the communication of the participants; intentions and emotions. Indeed participants often complain that the facial expressions or emotions of the other side are difficult to perceive, that it is difficult to carry on a friendly, warm conversation, or that it is difficult to convey one's intentions to the other. They thus tend to become irritated during these conferences, and at times make erroneous judgements. In such situations, it can be said that the system users are being deprived of their humanity. This occurs because a machine or computer, when placed between two people communicating, interferes with a natural communication. What measures are there then to achieve a natural communication in such a setting, with a machine or computer between those communicating? These methods are classified here. In this study, a system for communicating 'presence' was employed to achieve a natural communication. The prototype system is call a 'dummy head for 3-D audiovisual recording'. Using this dummy head, dialogue between operators, remote control, as well as the recording of a skilled worker's use of his hands were carried out, and the results were evaluated. From these results, the authors report on how the prototype system, when placed between humans, helps to achieve a natural communication. Finally, some examples are given to show the human need for achieving a natural communication in such interface situations.

[Three cases of hydronephrosis in which the indwelt ureteral stent was ineffective. Urodynamic studies using a stent indwelling model for retroperitoneal fibrosis]

We report 3 cases in which ureteral stents were indwelt to treat hydronephrosis due to retroperitoneal fibrosis, resulting in aggravation of hydronephrosis and renal function. An urodynamic study was carried out to determine the factors that aggravated hydronephrosis. The subjects were a 59-year-old male with prostatic cancer and bilateral hydronephrosis due to intrapelvic lymph node metastasis, a 49-year-old female with retroperitoneal lymph node metastasis and bilateral hydronephrosis following surgery for stomach cancer, and a 65-year-old male with hydronephrosis due to idiopathic retroperitoneal fibrosis. Indwelling of ureteral stents in the 3 patients resulted in aggravation of hydronephrosis and renal function. Stent indwelling models of retroperitoneal fibrosis were produced using adult mongrel dogs. A pressure flow study was carried out through the nephrostomy in each experimental model to determine the intrapelvic pressure and urine volume. In all stent indwelling models, the urine volume showed changes similar to those in the controls. In the stent indwelling models, the intrapelvic pressure showed a significant increase with an increase in the volume of water instilled through the nephrostomy in the stent indwelling models with retroperitoneal fibrosis, unlike the controls and models with ureteral stenosis. In conclusion, the clinical cases and model experiment suggested that unlike partial ureteral stenosis, in ureters in which extensibility was disturbed in an extensive area, the indwelt stent caused an increase in the resistance of the liquid flowing in the ureter, aggravating hydronephrosis.

[Pressure changes in the renal pelvis of the dogs in response to a sudden rise in intravesical pressure, examined in the presence of resico ureteral reflux with artificial ureter and/or pelvis]

This study is to determine which part or the upper urinary tract, ureter or pelvis causes more significant delay in the pressure wave-front propagation from the bladder to the pelvis when a reverse flow of the urine occurs. A sudden rise in the intravesical pressure of the dog was produced by stimulating the vesical branches of pelvic nerve with a train of electrical impulses with 10 Hz for 60 sec. In order to eliminate the physiological mechanism that presents a reverse flow of the urine at the uretero-vesical junction, a 3 cm vinyl tube was inserted into the ureteral orifice in all experiments except the cases with ureteral substitution (group II and III). Changes in intrapelvic pressure were measured from 7 dogs without substitution of either ureter or pelvis, and used as the control responses for comparison with those recorded from the dogs with artificial ureter and/or pelvis. Artificial ureter was made by a vinyl tube of 25 cm, whereas artificial pelvis was made by a 3 ml plastic chamber. Twenty-eight dogs were divide into 3 groups. Group I consisted of 7 dogs whose pelvises were replaced by artificial ones. Group II included 8 dogs whose ureters were substituted by artificial ones, and group III consisted of 6 dogs whose both ureter and pelvis were replaced by artificial ones. Results obtained were as follows; (1) There was no significant difference between the maximum intravesical pressure and the maximum intrapelvic pressure recorded from every dog in all groups. (2) The onset time of intrapelvic response recorded from the control dog showed a delay from that of intravesical response by 2.05 +/- 1.03 sec. (3) The onset time of intrapelvic response recorded from group I, II and III were 0.51 +/- 0.94 sec., 1.95 +/- 1.10 sec., 0.10 +/- 0.25 sec., respectively. (4) Statistically significant difference in the delay of response was observed only between the responses recorded from the control or group II and the responses recorded from group I or III. The above results suggested that the major site causing a significant delay in the pressure wave-front propagation from the bladder to the pelvis is the pelvic area including caryx, but not the ureteral region, when a reverse flow of the urine occurs.

An analysis of the reduction of elasticity on the ageing of human skin and the recovering effect of a facial massage

Based on a study of human hand movements during practical diagnosis, evaluation patterns of softness and elasticity were observed. The evaluation models were extracted from these analyses and applied to the developing a method of detecting the dynamic properties of human skin. The device consisted of a robot arm controlled by microcomputer system and a probe with a mounted mechanical strain gauge. A method was developed to measure the dynamic properties of human skin. Correlations were obtained between parameters from the measurements and the values evaluated by experts. The dynamic properties of the cheek skins of a panel of 86 people, aged from 20 to 75 years, were measured. A remarkable reduction in elasticity was observed in older people and the lack of sebum was analysed. From these results the metabolism in the skin surface and the muscles of the cheeks were analysed. The effects of skin care products were then confirmed by measuring cheeks before and after continual use of facial treatment systems for a month. Significant recovery effects were observed in a less soft-skinned group and a less elastic-skinned group over 30 years of age. These experiments suggest a protecting effect of facial treatments and skin care products.

[A case of scrotal bladder hernia containing bladder cancer]

A 70-year-old man had a history of total laryngectomy for laryngeal cancer and bilateral inguinal hernia repair 5 years previously. The patient had suffered from difficulty with urination since then and had been treated for prostatic hypertrophy at our department. He developed microscopic hematuria from June 1991, and was admitted because a bladder tumor was detected by cystoscopy. Cystography showed a scrotal bladder hernia with filling defects in the bladder per se and the bladder hernia as well. Cystoscopy revealed tumors in the hernia and in the vicinity of the ureteral orifice. Biopsy indicated transitional cell carcinoma. Voiding cystourethrography showed normal urination and no residual urine. Excision of the tumor-containing hernia, partial cystectomy with right ureteral orifice, and reconstruction of the right inguinal canal were performed on October 25, 1991. The postoperative course was favorable and he was discharged on the 40th postoperative day. The tumors were respectively stage as TCC, G1, and pT1a, and TCC, G1 greater than G2, and pT1b. Thirty five cases of bladder hernia that have been reported in Japan. Eight cases of accompanied by cancer have been reported in Japanese (3 cases) and foreign (5 cases) literatures. These are reviewed and discussed.

[Ureteral function at the ureterovesical junction. Action potentials of the canine intramural ureter during bladder filling or bladder contraction]

The relationship between bladder movements and the intramural ureter was studied in the dog by recording electromyograms of the intramural and extravesical ureters recorded during bladder filling and contraction. Bladder filling was achieved by instilling physiological saline at a rate of 10 ml/min to a volume of 5 ml/kg, while bladder contraction was induced by electrical stimulation. For electromyography, an electrode was inserted transperitoneal into both the extravesical ureter and the intramural ureter after it had been separated from the extravesical ureter. A cystostomy for the instillation of water and another cystostomy for the measurement of intravesical pressure were also made in the bladder. During bladder filling at an intravesical pressure of about 10 cmH2O, the frequency of the action potentials in the intramural ureter showed no significant difference to those in the extravesical ureter. In addition, during bladder contraction at a greatly increased intravesical pressure of about 5 times the precontraction level, the frequency of the action potentials in the intramural ureter was not significant by different from those in the extravesical ureter, and also from its own precontraction value. The above findings suggest that action potentials in the intramural ureter are not affected by bladder movements such as filling or contraction, and that the ureter continues to actively transport urine to the bladder during such movements.

[A case of replacement ileocystoplasty for contracted bladder]

The patient was a 49-year-old male. He had a history of asymptomatic hematuria that had occurred 3 years previously. The hematuria and pollakisuria developed again from about March, 1989, and he was hospitalized for bladder tamponade in April. Bilateral percutaneous nephrostomies were performed because a contracted bladder and bilateral hydronephrosis were detected. He was then admitted to our hospital on June 21. The cause of the contracted bladder was not evident, despite extensive examination. A replacement ileocystoplasty constructed by Shishido's method was used to replace the contracted bladder. A U-shape pouch was prepared by detubularization of 25 cm of the ileum and this pouch was anastomosed to the incised end of the bladder neck after subtotal cystectomy. The ureter and ileum were then anastomosed using Coffey's method. The bladder capacity and the maximum urinary flow rate after 1 year were 350 ml and 13 ml/sec, respectively, and residual urine was not noted after urination even following abdominal pressure. Urinary incontinence was not noted either.

[Clinical experience with cefbuperazone in complicated urinary tract infection]

Cefbuperazone (CBPZ) was administered to inpatients with complicated urinary tract infections (UTI) at our department. Clinical efficacy and safety were evaluated in 22 chronic cases by the criteria for evaluation of clinical of antimicrobial agents on urinary tract infection. Overall clinical efficacy was excellent in 8 cases, moderate in 9 cases and poor in 5 cases with an effectiveness rate of 77%. Twenty-four of the 34 strains isolated from the patients were eradicated and eradication rate was 71%. Neither subjective nor objective adverse reactions were observed. Abnormal changes in laboratory tests were found in 9 patients, but were probably not related to CBPZ administration. Judging from these results, CBPZ is considered to be an effective and safe antibacterial for the treatment of complicated UTI.

[Analyses of industrial society from ecology--modeling analyses of industrial ecological system]

A macroscopic industrial ecological model has been developed to investigate the effects of changes in industrial structure on social well-being in general and health in particular. The model is composed of the following sectors: industry and employment, environment and pollution, and population and health care. The model was calibrated using available data of the past 60 years for Japan. The simulation study was conducted with the time span of 1920 to 2000. The results indicated that the gradual shift, in the industrial structure of Japan, would improve the level of living standards resulting in enhanced health service capability and lower death rate although increasing adult disease rates in the aged society. Also the rapid future growths of service industry and information and communication were observed.

[The working adaptation in visual display terminal (VDT) workers]

The working adaptation in VDT workers was conducted by investigating from two different standpoints: one was to indicate an improvement of working conditions and environments around the VDT workers, evaluating the fundamental data of their visual physiological functions, and the other was to investigate the relation between their performances and production. The results were as followed: 1. Eye strain induced by VDT work was able to take an objective view as accommodative and convergent depression including the tear productive function, followed by making good working conditions. 2. The measurement of eye movement was able to analyze the response time and the response process for the informations indicating on the display, and the concept of recovery time for deteriorated accommodative function was useful to improve the display design. 3. It was suggested that the measurement of visual evoked potential was more simple method to evaluate the workers' attention. 4. The relation between performance and psychological stress and the time course analysis of performance were studied, so that it was given suggestions as to assign suitably the work management and the working design to each VDT worker.

Influence of VDT (visual display terminals) work on eye accommodation

Visual display terminals (VDT) are popular in offices. Many VDT operators have complained about eye-function impairment. Experiments using an accommodo polyrecorder and an infrared optometer showed that visual tasks in VDT work might induce temporary effects in the visual accommodation system; prolonged the near point distance and the contraction time of accommodation and increased the low frequency component of the small fluctuation of accommodation after VDT work. The inhibition of accommodation caused by VDT work was more severe than that caused by the conventional hard-copy work, and changes in the accommodative function were found with statistical significance in the smaller-size character group but tended to deteriorate in the larger-size character group. The inhibition was more evident in the elderly and middle age groups than in the young age group. The inhibition of accommodation by VDT work might be inhibited by administration of methylcobalamin.

A descriptive model of visual search

This study used the corneal reflection technique to investigate causes of miscounting in a dot-counting inspection task. An analysis of subjects' eye movements showed that there were two causes of miscounting: making fewer eye movements than the number of objects to be counted and overlooking objects present in the boundary of the visual field. The type of miscounting depended on the number of dots to be counted and the time allotted. Search process trade-off curves were developed that show the proportion of the two processes in a trial. These curves were incorporated into a descriptive model of visual search.

Determination of counting time in visual inspection

A series of experiments was conducted to clarify the relationship between the time required and visual process for counting dots projected onto a screen. The eye movement of the subject on each experimental trial was recorded by the electro-oculograph method and eye mark recorder. According to the experimental results, the subject used two information processes depending on the number of dots and symmetry of patterns. Both latency and movement time depend on the configuration of dots in the sample. An excess number of saccades is one of the causes for miscounting. A model for estimating counting time was built on the basis of the findings obtained. The time estimated by the model, if the maximum number of saccades does not exceed the number of dots on each sample, may be taken as optimum counting time.

Studies on avian infectious bronchitis virus (IBV). II. Propagation of IBV in several cultured cells

The growth of ten strains of avian infectious bronchitis virus (IBV) in several cultured cells was examined. The cultured cells used were chick kidney (CK), chick embryo (CE), HeLa and BHK-21 cells. The results obtained can be summarized as follows. 1. All the strains showed similar growth curves in CK cells. Progeny viruses appeared in the culture medium 4 to 6 hours after inoculation and peak virus titers of 10(6.5)--10(8.5) TCID50 per 0.1 ml were obtained after 36 hours. A cytopathogenic effect (CPE) was detected within 24 hours. No distinct CPE and low multiplicities were observed on culturing at 30 degrees C. 2. All strains replicated in CE cells, although only small amounts of virus were produced. No CPE was observed. 3. Only Beaudette-42 and Holte strains grew in BHK-21 cells. 4. No IBV strains grew in HeLa cells.