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Epoxy resins (EP) are commonly used to power apparatus due to their excellent electrical, thermal, and mechanical properties. Two types of EP resins were prepared to develop the varnishes for a rotating machine winding. A bifunctional alicyclic EP were used as an EP main resin, and an acid anhydride [mixture of hexahydro phthalic anhydride and methyl hexahydro phthalic anhydride (HHPA), or methyl nadic anhydride (NMA)] were used as a curing agent. The DC and impulse breakdown strengths of the EP‐HHPA were higher than that of EP‐NMA regardless of the applied voltage waveform and the temperature. The PDIV of the twisted pair sample coated with EP‐HHPA under the surge voltage application was also higher than that of twisted pair sample without the coating with EP resin and that with EP‐NMA. Furthermore, the transferred and/or accumulated charge amount of the EP‐HHAP on bulk and surface properties at high temperatures were superior to that of EP‐NMA. From these results, it is considered that EP‐HHPA may be preferable varnishes materials than EP‐NMA for a rotating machine winding. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

The frontal part of the Japan Trench plate‐boundary fault is enriched in low‐strength smectite, and this material characteristic is thought to be a factor for the large fault slip during the 2011 Mw 9.0 Tohoku‐oki earthquake. In this study, we evaluated the surface physicochemical properties of the particles that constitute the fault zone and examined their effect on the rheological properties of the fault. Measurements of the zeta potential, surface free energy and pore size distribution indicate that the interparticle interaction in the in situ state is very weak. This means that the viscous resistance is low, which may have contributed to the large fault slip during the earthquake. The interparticle distance appears be longer than the energetically stable state, which may reflect a transitory state after the earthquake. Changes in microscopic interparticle interactions during coseismic and interseismic periods may influence the rheological behaviors of the Japan Trench plate‐boundary fault. Plain Language Summary: Faults in the shallow crust commonly contain abundant clay minerals, and if these clayey faults are saturated with water, then the faults may behave like viscous fluid. The behavior of such fluid is also strongly dependent on interactions between particles in the fluid. In this study, we examine the physicochemical properties of the surfaces of clay particles that constitute the Japan Trench plate‐boundary fault to investigate the interactions between these particles. Our results suggest that such microscopic forces may be one of the factors that control the slip resistance of this fault and its strength recovery process. Key Points: The zeta potential and surface free energy of smectite‐rich fault gouge samples were determined for the Japan Trench plate‐boundary faultThese energies enabled the calculation of interparticle potential under high‐salinity conditions (such as beneath the seafloor)Such microscopic interactions may be the dominant factor in the sliding resistance and strength recovery of the fault [ABSTRACT FROM AUTHOR]

The evaluation of the representation of the surface downward shortwave flux (DSF) from atmospheric reanalysis data products is required to obtain reliable information for the resource assessment of surface solar energy. The representation of the DSF from the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), reanalysis data product was evaluated using surface solar radiation from ground-based observations in Japan. The cloud fraction (CFR) and cloud optical thickness (COT) from Moderate Resolution Imaging Spectroradiometer (MODIS) were also used as references. The CFR from MERRA-2 tends to be smaller than that from MODIS, and the correlation between the difference in the CFR and that in the DSF is negative. The correlation between the difference in the COT and that in the DSF is weakly negative. To quantify the effects of the difference in the CFR and COT to that of the DSF, a regression model based on an artificial neural network architecture that emulates the process of the DSF in MERRA-2 was constructed. Numerical experiments using the emulator quantify contributions of each of the differences in the CFR and COT and joint contributions of the two variables. In addition, a cluster analysis was performed to clarify the differences in the seasonal changes in the monthly mean bias error (MBE) in the DSF among ground observation stations, and three clusters were identified. Contributions of the differences in the CFR and COT to the seasonal change in the monthly MBE were also clarified using the results of the numerical experiments. [ABSTRACT FROM AUTHOR]

Purpose: To determine the in vitro antimicrobial activity of quinolones against major bacterial isolates from the ocular surface bacterial flora of patients in a tertiary hospital for selection of optimal antibiotic eye drop during the perioperative stage. Methods: The conjunctival sac scraping of 933 patients who underwent ophthalmic surgery was cultivated and bacterial species of the isolates were identified. The minimum inhibitory concentrations (MICs) of gatifloxacin (GFLX), moxifloxacin (MFLX), levofloxacin (LVFX), and tosufloxacin (TFLX) were measured by microdilution methods. The cumulative percentages of MICs of 4 quinolones against major bacteria were calculated. The concentrations of quinolones inhibiting 50% (MIC50) and 90% (MIC90) of the major bacteria were compared. Results: The study mainly included 784 patients scheduled for cataract surgery, 73 for vitrectomy, 30 for corneal transplantation, 30 for conjunctival surgery, 11 for eyelid surgery. The most frequently isolated bacterium was coagulase-negative Staphylococci (CNS) (184 strains), followed by Corynebacterium (107 strains), Staphylococcus aureus (33 strains), Streptococcus (18 strains), and Enterococcus (13 strains). The percentages of methicillin-sensitive CNS isolates for which MIC of GFLX, MFLX, LVFX, and TFLX was 0.06 μg/mL or less were 8.0%, 13.4%, 5.4%, and 63.4%, respectively. Similarly, the percentage for Corynebacterium was 23.0%, 23.0%, 0%, and 35.6%, respectively. MIC50 of TFLX for Streptococcus and Enterococcus showed the lowest values, 0.12 and 0.25 μg/mL, respectively. Conclusions: Among 4 quinolones, TFLX has the highest in vitro antimicrobial activity against major bacterial isolates from the ocular surface bacterial flora of patients in a tertiary hospital. [ABSTRACT FROM AUTHOR]

Purpose: To compare the shear-bond-strength (SBS) of a highly-filled-flowable composite (HFFC) and a paste-type composite for indirect composite repair and to evaluate the effect of different surface treatments (ST), concerning the composite repair protocol., Methods: Eighty-four 5 × 5 × 2 mm cylindrical specimens were prepared using Gradia Plus and SR Nexco indirect composite materials. The samples were thermocycled 5,000 times. According to the ST, the samples were divided into three groups (control, bur, and air-abrasion). After ST, the sample subgroups were divided into two sub-groups according to the repair material: paste-type composite and HFFC (n = 7). Another 5,000 cycles of aging were performed. SBS values were measured with a universal testing machine (Shimadzu, Japan). Shapiro-Wilk, 3-way ANOVA, and Tukey HSD test were used to evaluate data (P < 0.05)., Results: ST was considered significant for SBS (P < 0.001). The mean values were (13.9 ± 5.7), (17.0 ± 6.4), (20.4 ± 4.9) MPa for the control, bur and phosphoric acid, and air-abrasion groups, respectively. The surface treatment and repair material interaction was considered significant for SBS (P = 0.044). The highest mean bond strength (24.5 ± 4.5 MPa) was observed for the interaction of SR Nexco, air-abrasion ST, and HFFC repair., Conclusion: Repairing with HFFC following air abrasion might enhance the SBS for indirect composite restorations.

The article discusses a study on the effectiveness of balance training performed using a foam rubber pad in improving balance and reducing the number of falls of study participants. Topics discussed include the participants' 60-weekly exercise class for 4 months supplemented with daily home-based exercises and findings that a balance training program was effective for improving physical function in community-dwelling older adults.

The objective of this study was to analyze and assess the clinical performance of direct composite restorations using a nanohybrid and a nanofill composite material for posterior teeth in patients with amelogenesis imperfecta (AI). This study involved 15 patients between the ages of 14 and 30 years suffering from amelogenesis imperfecta (AI). During the study, the patients received direct composite restorations using either the Clearfil Majesty ES-2 (Kuraray Medical Inc, Tokyo, Japan) and Clearfil Universal Bond (Kuraray) or Filtek Ultimate Universal Restorative (3M ESPE, St Paul, MN, USA) and Single Bond Universal Adhesive (3M ESPE). The evaluations of the restorations were conducted per the modified USPHS criteria at the time of baseline as well as during the first-, second-, third-, and fourth-year follow-up sessions. After four years, it was observed that the cumulative success rate of direct posterior restorations was 98.1% for Clearfil Majesty ES-2 and 92.2% for Filtek Ultimate. During the study one Clearfil Majesty ES-2 restoration and four Filtek Ultimate restorations failed. There was a significant difference between Clearfil Majesty ES-2 and Filtek Ultimate in the color match in posterior restorations after three and four years. The causes of failure included marginal discoloration and caries, as well as fracture of the restoration. Hence, it can be stated that the use of nanohybrid or nanofill composites in posterior direct restorations in patients with AI looks promising. The failure rate of Clearfil Majesty ES-2 was found to be lower than that of Filtek Ultimate restorations. Clinically, the rate of optimum restorations conducted for partial discoloration, marginal adaptation, color match, and surface texture were observed to be higher when Clearfil Majesty ES-2 was used. However, additional studies are needed to assess the clinical performance of direct posterior composite materials in patients with AI., (©Operative Dentistry, 2022.)

Objectives: To compare gloss retention of four different resin composites with their corresponding CAD/CAM composite blocks., Materials and Methods: Four direct resin composites (Filtek Supreme XTE A2 Body (3M, USA), Tetric EvoCeram A2 (Ivoclar Vivadent, Liechtenstein), GrandioSO x-tra A2 (VOCO, Germany), G-aenial Universal A2 (GC, Japan)), and their corresponding CAD/CAM composite blocks were tested. A total of 288 samples were prepared and three different tests were performed: brushing, exposition to acidic fluoride gel and exposition to alcoholic solution. Gloss values were obtained by means of a glossmeter at T0 before aging and T60 after 1 h of aging., Results: Mean gloss values ranged from 0.9 after brushing tests to 79.0 after the alcohol test witnessing a high gloss variability depending on the materials and the aging test. Statistical analysis by means of two-way repeated measures ANOVA followed by Fisher's LSD post-hoc test revealed significant differences between materials, storage media, and their interactions., Conclusion: Gloss retention seems to be dependent on the composite type (direct or CAD/CAM block) and composite brand and varies in respect to the type of aging. CAD/CAM materials showed a higher resistance toward alcohol exposure., (© 2021 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Systematic simulations were performed in a city block in Yokohama, Japan, on a clear summer day to study the effects of building surface thermal properties on their radiative and thermal exchange with the atmosphere, and the surface energy balance (SEB) model sensitivity to these thermal properties. To study this practically and systematically, the thermal properties used were determined from a database of commonly used materials for building surfaces in urban Japan, characterizing the typical thermal property values and their combinations. Using suitable simplification and assumption, the main findings included: (a) a combined modification of thermal properties enlarges the cooling effects of individual modifications, reaching 131%–149% of the accumulated reduction in the emitted sensible heat flux (Q H); (b) the difference in the cooling effects of a high-albedo strategy applied to roofs between various thermal properties is up to 76 [W m−2] in Q H ; (c) the SEB model sensitivity of the surface temperature (T s) to thermal properties for the façade is close to that of the albedo, at up to approximately 0.1 °C for a thermal conductivity Δ λ c of 1 [W m−2 K−1] and a heat capacity Δ C a of 1 [kJ m−2 K−1]; (d) the range in root mean square error of the simulated daily, daytime, and noon Q H caused by generalizing the roof thermal properties is estimated to be 6%–41%, 7%–50%, and 7%–38%, respectively. Overall, the thermal properties of building surfaces are important for their thermal and radiative behavior, and therefore cannot be ignored in SEB modeling. • Importance of thermal property for surface heat balance is verified systematically. • Combined modification of thermal properties enlarges individual cooling effects. • Thermal properties cannot be ignored to evaluate the cooling effect of cool roofs. • Generalizing the thermal properties causes nonnegligible errors in SEB modeling. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to monitor the behavior of interfacial gaps formed under different bonded polymeric restorations before and after thermocycling (TC), using swept-source optical coherence tomography (SS-OCT) and confirming the obtained findings with confocal laser scanning microscopy (CLSM)., Materials and Methods: Cylindrical class I cavities were prepared in twenty noncarious human premolar teeth (1.5 mm depth × 3.5 mm diameter) and divided randomly into two groups: TS and SN, according to the adhesive system ( n = 10). In the TS group, one-step self-etch adhesive Clearfil Tri-S Bond Plus (Kuraray Noritake Dental, Japan) was used, followed by composite restoration using Estelite Sigma Quick (Tokuyama Dental, Japan). In the SN group, the cavities were restored with the two-step self-etch/composite silorane-based resin restoration system (3M ESPE, USA). All specimens were restored in bulk filling technique and cured in accordance with the manufacturers' instructions. Both groups were imaged under SS-OCT after 24 h and recorded as controls. Then, each group was subjected to thermal challenge using the TC machine (5-55°C) and B-scans were recorded at different TC intervals (2600, 5200, and 10000). In order to confirm the SS-OCT findings, additional specimens were prepared, scanned, and sectioned for CLSM observation., Results: B-scans demonstrated white clusters at the tooth-resin interface that corresponded to the gap location on CLSM images. The TS group showed significantly less gap formation than the SN group before and after TC ( p < 0.001)., Conclusions: An optimal composite adaptation can be achieved when the bonded restoration comprises a combination of an adhesive containing 10-MDP monomer and a considerable highly filled composite., Competing Interests: There were no conflicts of interest., (Copyright © 2021 T. A. Bakhsh and A. Turkistani.)

Purpose: To determine the in vitro antimicrobial activity of quinolones against major bacterial isolates from the ocular surface bacterial flora of patients in a tertiary hospital for selection of optimal antibiotic eye drop during the perioperative stage. Methods: The conjunctival sac scraping of 933 patients who underwent ophthalmic surgery was cultivated and bacterial species of the isolates were identified. The minimum inhibitory concentrations (MICs) of gatifloxacin (GFLX), moxifloxacin (MFLX), levofloxacin (LVFX), and tosufloxacin (TFLX) were measured by microdilution methods. The cumulative percentages of MICs of 4 quinolones against major bacteria were calculated. The concentrations of quinolones inhibiting 50% (MIC 50 ) and 90% (MIC 90 ) of the major bacteria were compared. Results: The study mainly included 784 patients scheduled for cataract surgery, 73 for vitrectomy, 30 for corneal transplantation, 30 for conjunctival surgery, 11 for eyelid surgery. The most frequently isolated bacterium was coagulase-negative Staphylococci (CNS) (184 strains), followed by Corynebacterium (107 strains), Staphylococcus aureus (33 strains), Streptococcus (18 strains), and Enterococcus (13 strains). The percentages of methicillin-sensitive CNS isolates for which MIC of GFLX, MFLX, LVFX, and TFLX was 0.06 μg/mL or less were 8.0%, 13.4%, 5.4%, and 63.4%, respectively. Similarly, the percentage for Corynebacterium was 23.0%, 23.0%, 0%, and 35.6%, respectively. MIC 50 of TFLX for Streptococcus and Enterococcus showed the lowest values, 0.12 and 0.25 μg/mL, respectively. Conclusions: Among 4 quinolones, TFLX has the highest in vitro antimicrobial activity against major bacterial isolates from the ocular surface bacterial flora of patients in a tertiary hospital.

Clinical Relevance: The clinical performance of both conventional and flowable giomer restorative materials was particularly good in Class I restorations after three years of service., Summary: This study evaluated and compared the clinical performance of a flowable and a conventional giomer restorative material after three years. Forty-four pairs of restorations (total n=88) were placed in Class I cavities with either a flowable giomer (Beautifil Flow Plus F00; Shofu Inc, Kyoto, Japan) or a conventional giomer restorative material (Beautifil II; Shofu Inc) after the application of a dentin adhesive (FL-Bond II; Shofu Inc) and a flowable liner (Beautifil Flow Plus F03; Shofu Inc). After 3 years, 39 pairs of restorations were evaluated with the modified United States Public Health Service criteria, and digital color photographs of restorations were taken at each patient visit. The evaluation parameters were as follows: color match, marginal integrity, marginal discoloration, retention, secondary caries formation, anatomic form, surface texture, and postoperative sensitivity. Evaluations were recorded as a clinically ideal situation (Alpha), a clinically acceptable situation (Bravo), or a clinically unacceptable situation (Charlie). Data were analyzed with Fisher's exact and McNemar tests (α=0.05).None of the restorations showed retention loss, postoperative sensitivity, secondary caries, or color change. The performance of Beautifil II in terms of marginal integrity, marginal discoloration, and surface anatomic form was significantly lower at the 36-month follow-up than at baseline (p=0.007). There were no significant differences between the baseline and 36-month follow-up scores for the other criteria for Beautifil II (p>0.05). No differences were found between the baseline and the 36-month follow-up scores for any of the criteria for Beautifil Flow Plus F00 (p>0.05). No statistically significant difference in overall clinical performance was found between the 2 materials after 36 months (p>0.05).The three-year clinical performance of both restorative materials (Beautifil Flow Plus F00 and Beautifil II) was very good and not significantly different for any of the parameters evaluated., (©Operative Dentistry, 2021.)

The characteristics of seismic signals generated by the mass movement are considered to reflect the physical properties of the movement, and the use of seismic data for landslide studies has recently attracted increased attention. Some landslides produce very small earthquakes associated with slip initiation, which can be observed by nearby seismic stations. The 2015 Rausu landslide in Japan and the 2016 Nuugaatsiaq landslide in Greenland showed repeating small earthquakes before the catastrophic failure. The small earthquakes have very similar waveforms with different amplitudes and time intervals. The events continued for about 10-20 hours followed by the large deformation of the landslide.These seismic sequences are considered to be evidence of stick-slip movement of the landslide before the large failure occurs. The nearly identical waveforms suggest that the source locations and mechanisms are very similar in the sequence, which indicate that the seismic events are generated at a particular small area. The amplitudes and time intervals of the events may reflect the physical properties of the slip surface. Larger amplitudes and/or shorter time intervals of the seismic events suggests an increase of the shear stress accumulation during the precursory creeping stage. Similar apparent stick-slip behavior has also been observed during movement of glaciers and ice sheets at the contact between ice and bedrock. These observations suggest that the heterogeneous structure, such as asperities on the slip surface plays an important role in controlling the movement of landslides, and adds a new aspect to the conventional understanding of mechanisms that control the mass movement. [ABSTRACT FROM AUTHOR]

Background: The objective of our study was to compare the upper and lower surface microhardness and surface changes of Glass Carbomer Cement (GCP) and EQUIA Forte (EF) in different thickness after thermo-light curing durations and aging., Methods: A total of 504 samples (5 mm-diameter) were prepared by using GCP-252 (GCP Dental, and Vianen, Netherlands) and EF-252 (EQUIA Forte, GC, Tokyo, Japan). Three different thickness samples (2, 4, and 6 mm) were prepared with 84 samples in each subgroup. The samples were prepared by three curing procedures (Non-exposed, 60s, 90s). Their varnishes were applied to the upper surfaces of half of each subgroup (n = 7). The upper microhardness measurements were evaluated before and after aging. To compare the effect of different thicknesses, the bottom surfaces of the samples were evaluated before aging in terms of microhardness measurements. Also, the upper surfaces were analyzed in the SEM before and after aging., Results: The upper surface values of all the samples were higher than the bottom values (p < 0.05). There were no significant differences between the varnished and non-varnished samples in both materials (p > 0.05). Although this increase was not significant in some groups, temperature variations increased the surface microhardness values of both materials except for the non-exposed-varnished EF samples. The highest microhardnesses values were recorded in the non-exposed-varnished EF (125.6 ± 6.79) and unvarnished GCP (88.1 ± 7.59) samples which were thermo-light cured for 90 s before aging. The bottom hardness values were affected by thickness variations in both GCP and EF materials (p < 0.05). The sample deformations and microcracks after aging were greater than before in all the materials. Thermo-light curing in 90 s to the samples reduced the cracks in both the materials before and after aging., Conclusions: Thermal aging adversely affected the microhardness of the materials, which is important for clinical success. The thermo-light curing process improved the microhardness of the GCP group without varnish application. Varnish application increased the microhardness of the EF group without applying thermo-light curing. The microhardness of the bottom surfaces decreased with increasing thickness. The thermo-light curing did not increase the bottom surface microhardness of all the samples.

Background: Several methods exist for objectively evaluating chewing efficiency by using gummy jelly. However, the validity of the subjective visual evaluation of chewing efficiency has not been assessed., Objective: To verify with an epidemiological study, the validity of a visual scoring method using gummy jelly by testing the relationship between masticatory performance (MP) using a fully automatic measuring system and visual score (VS) using a visual scoring method., Methods: Community-dwelling elderly individuals (n = 1234) ≥70 years old participated. One evaluator measured VS consecutively after participants chewed the gummy jelly (ie, actual-VS). The chewed jelly was photographed. Two evaluators used the photograph to measure the gummy jelly (ie, photo-VS). To test the validity of both methods, the correlation between actual-VS and MP and between photo-VS and MP were analysed. Inter-rater reliability between the evaluators of photo-VS was analysed., Results: Significant correlations existed between actual-VS and MP and between photo-VS and MP (r = 0.86-0.87; P < 0.001). The intra-class correlation coefficient of the inter-rater reliability for photo-VS was very high (0.93; P < 0.001; 95% confidence interval: 0.877-0.953); however, the distribution of photo-VS deviated slightly from the actual-VS. A large coefficient of variation in the MP for low VSs suggested the influence of incomplete comminution, which was not reflected by the VS, and the accidental swallowing of small pieces during chewing., Conclusion: The VS deviated slightly from the MP calculated using a fully automated method; however, the VS can be utilised for epidemiological surveys with numerous participants., (© 2018 John Wiley & Sons Ltd.)

Objective: To evaluate the influence of saliva contamination and cleaning procedures on shear bond strength (SBS) of a self-adhesive resin cement (SAC) to zirconia surfaces., Materials and Methods: A total of 160 sandblasted zirconia blocks were randomly divided into eight groups as follows: No saliva contamination, no cleansing (NC-NC); contamination with saliva, no cleansing (SC-NC); no saliva contamination, cleansing with a zirconia primer (ZP; Z-Bond, Danville Materials, Inc., S. Ramon, California) (NC-ZP); contamination with saliva, cleansing with ZP (SC-ZP); no saliva contamination, cleansing with hydrofluoric acid (HF; Ultradent Porcelain Etch; Ultradent Products, South Jordan, Utah) followed by cleansing with ZP (NC-HF-ZP); contamination with saliva, cleansing with HF followed by cleansing with ZP (SC-HF-ZP); cleansing with ZP, contamination with saliva, cleansing with ZP (ZP-SC-ZP); application of ZP, contamination with saliva, cleansing with HF followed by cleansing with ZP (ZP-SC-HF-ZP). Cylindrical resin composite blocks were luted to the zirconia surfaces with SAC (Clearfil SA Cement Automix, Kuraray, Inc., Tokyo, Japan). Specimens were subjected to shear forces at a cross-head speed of 0.5 mm/min. Data were analyzed with Analysis of Variance and Tukey tests (α = 0.05)., Results: The bond strength values to zirconia were significantly influenced by saliva contamination (P < .05). The SC-NC group showed the lowest bond strength values (5.6 ± 1.4 MPa; P < .05). All cleansing or pretreatment agents improved the bond strengths when compared to noncleansing groups, NC-NC and SC-NC., Conclusion: In situations where saliva contamination is deemed unavoidable, application of ZP after try-in of the zirconia restoration could be beneficial for the accurate cementation., Clinical Significance: During try-in sessions of fixed dental prostheses, zirconia ceramic restoration may come into contact with saliva and surfaces should be cleansed to obtain an optimal surface for adhesion. Application of zirconia primer to the sandblasted zirconia surface is recommended whether the surface is contaminated with saliva or not., (© 2018 Wiley Periodicals, Inc.)

Categorizing the archaeological remains of Sus scrofa as domesticated "pigs" or wild "boars" is often difficult because of their morphological and genetic similarities. For this purpose, we tested whether feeding ecological change of S. scrofa that accompanied their domestication can be detected based on the three-dimensional texture created on the tooth enamel surface by mastication. We scanned the lower tooth surface of one wild and one stall-fed populations of modern S. s. leucomystax and one wild population of S. s. riukiuanus by using a confocal laser microscope. The average body weight of S. s. leucomystax is twice as heavier as that of S. s. riukiuanus. The textures were quantified using the industrial "roughness" standard, ISO 25178, to prevent inter-observer errors and to distinguish small differences that were difficult to detect by two dimensional image observation. The values of parameters related to height and volume were significantly larger in the stall-fed population. Twenty parameters differed significantly between the stall-fed and wild population of S. s. leucomystax, which indicated that the feeding ecological difference affected the ISO parameters of the two boar populations. Six parameters also differed between the wild populations of S. s. leucomystax and S. s. riukiuanus. Surprisingly, no parameter differed between the populations of stall-fed S. s. leucomystax and wild S. s. riukiuanus. Consumption of hard nuts and/or agricultural fruits and crops by the wild population of S. s. riukiuanus may have produced a tooth surface texture similar to that of the stall-fed population of S. s. leucomystax. Further analysis of S. s. riukiuanus with a known diet is necessary to conclude whether ISO parameters reflect the dietary transition accompanying the domestication of Sus (e.g., wild, semi-domestic, and domestic). Until then, caution is needed in discriminating domesticated populations from wild populations that mainly feed on hard objects., Competing Interests: The authors have declared that no competing interests exist.

Impacts of secondary generated minerals on mineralogical and physical immobilization of toxic elements were investigated for chelate-treated air pollution control (APC) fly ash of a municipal solid waste incinerator. Scanning electron microscope (SEM) observation showed that ettringite was generated after the moistening treatment with/without chelate. Although ettringite can incorporate toxic elements into its structure, elemental analysis by energy dispersive X-ray could not find concentrated points of toxic elements in ettringite structure. This implies that mineralogical immobilization of toxic element by the encapsulation to ettringite structure seems to be limited. Physical immobilization was also investigated by SEM observation of the same APC fly ash particles before and after the moistening treatment. The transfer of soluble elements was inhibited only when insoluble minerals such as gypsum were generated and covered the surface of fly ash particles. Neoformed insoluble minerals prevented soluble elements from leaching and transfer. However, such physical immobilization seems to be limited because insoluble mineral formation with surface coverage was monitored only one time of more than 20 observations. Although uncertainty owing to limited samples with limited observations should be considered, this study concludes that mineralogical and physical immobilization of toxic elements by secondary minerals is limited although secondary minerals are always generated on the surface of APC fly ash particles during chelate treatment.

Thermosoftening treatment of polyvinyl chloride (PVC) nasotracheal tubes (NTTs) can reduce the incidence and amount of epistaxis during nasotracheal intubation. The optimal thermal setting for thermosoftening treatment of NTTs without burn injury was investigated. Two composite types of PVC NTTs were used. Following withdrawal of the PVC NTTs from a bottle of water at 45 or 60°C, the changes in the surface temperature of the NTTs were measured by infrared thermography. Hardness of the NTTs at 25, 30, 35, and 40°C was measured. The incidence of epistaxis during nasotracheal intubation using thermosoftened NTTs was evaluated retrospectively. The surface temperature of both PVC NTTs dipped in 45 and 60°C water decreased to below body temperature 30 seconds after withdrawing them from the bottles. Although thermosoftening treatment proportionally decreased the hardness of both types of NTTs, the degrees differed according to their composition. When avoiding impingement of the NTT on the posterior wall of the nasopharynx, the incidence of mild and moderate epistaxis was 2.3%. Flexibility of PVC NTTs could be obtained by thermosoftening treatment at 60°C without burn injury. Thermosoftening treatment of PVC NTTs may be useful to avoid epistaxis during nasotracheal intubation.

Background: Our previous study into assessing hospital cleanliness in Japan by two common methods, ATP bioluminescence and the stamp agar method, revealed considerable variability in the data of both methods (BMC Research Notes, 7: 121, 2014). To investigate the reason(s) for the variability, we reanalyzed the data (n = 752) from the point of view of the material surface properties of sampling sites., Methods: Data obtained from surfaces with unknown properties and different purposes such as floor were omitted, and the remaining data (n = 488) were used for this study. The material surface properties on sampling sites were divided into six categories: melamine coated (n = 216), vinyl chloride (n = 16), stainless steel (n = 144), wood (n = 63), and acrylonitrile-butadiene styrene resin coated (n = 48). The data between individual material properties were compared., Results: The ATP values of high-touch places were significantly different depending on the type of surface, but no significant difference in stamp values between material properties was seen, indicating that in contrast to stamp values, ATP-accumulation more depends on the physical properties of the material surface such as electronic charges or roughness. To confirm this, we assessed a degree of roughness on vinyl chloride material surface (disutilized floor samples actually used for each of the hospitals) by observation with scanning electron microscope (SEM). As a result, SEM observation similarly revealed considerable roughness on the materials, which may allow microbes to contaminate the materials without noticing it., Conclusion: Material properties must be considered when evaluating hospital cleanliness with ATP values, and provide a strong warning into evaluating hospital cleanliness.

Here we present the first report of a carbon-γ-Fe₂O₃ nanoparticle composite of mesoporous carbon, bearing COOH- and phenolic OH- functional groups on its surface, a remarkable and magnetically separable adsorbent, for the radioactive material emitted by the Fukushima Daiichi nuclear power plant accident. Contaminated water and soil at a level of 1,739 Bq kg(-1) ((134)Cs and (137)Cs at 509 Bq kg(-1) and 1,230 Bq kg(-1), respectively) and 114,000 Bq kg(-1) ((134)Cs and (137)Cs at 38,700 Bq kg(-1) and 75,300 Bq kg(-1), respectively) were decontaminated by 99% and 90% respectively with just one treatment carried out in Nihonmatsu city in Fukushima. Since this material is remarkably high performance, magnetically separable, and a readily applicable technology, it would reduce the environmental impact of the Fukushima accident if it were used.

Objective: A common haplotype M2 consisting of minor SNP alleles located in the ANXA5 gene promoter region has been described as a risk factor for various obstetric complications such as recurrent pregnancy loss, pre-eclampsia and pregnancy-related thrombophilic disorder. However, the question of whether it is the maternal or fetal genotype that contributes to the onset of these disorders remains to be resolved., Methods: We analyzed ANXA5 gene variants in the blood and placental tissues from pre-eclampsia patients and normotensive controls. ANXA5 expression was examined by qRT-PCR, Western blotting and immunostaining. Results were compared between M2 and non-M2 carriers., Results: The M2 haplotype was found to be significantly frequent in placentas from pre-eclamptic patients relative to the controls (25.5% versus 10%, P = 0.044), In contrast, no significant differences were observed in maternal blood (13.0% versus 11.3%, P = 0.597). The placental expression of ANXA5 mRNA was found to be lower in M2 carriers. When examined by Western blot and immunostaining, the ANXA5 protein levels were found to be affected more by the placental than the maternal genotype. Histological examination of the placentas from the pre-eclamptic patients demonstrated that a placental M2 haplotype correlated more closely than maternal M2 with the severity of perivillous fibrin deposition., Conclusions: Although preliminary, these results suggest that hypomorphic M2 alleles in the in placental ANXA5 promoter, whether transmitted maternally or paternally, might be an essential determinant of an increased risk of pre-eclampsia via local thrombophilia at the feto-maternal interface., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Magnetic molecularly imprinted polymers (M-MIPs) for bisphenol A (BPA) and its structural analogues have been prepared by a multi-step swelling and polymerization method using uniformly-sized magnetic particles as a shape template. Binding experiments and Scatchard analyses revealed that two classes of binding sites were formed on M-MIP(BPA). The retention and molecular-recognition properties of M-MIPs for BPA and its structural analogues were evaluated using a mixture of phosphate buffer and acetonitrile or a mixture of water and acetonitrile as a mobile phase by LC. M-MIPs for BPA and [²H₁₆]BPA (BPA-d₁₆), M-MIP(BPA) and M-MIP(BPA-d16), showed almost the same imprinting factors for BPA, while M-MIP for bisphenol B (2,2-bis(4-hydroxyphenyl)butane, BPB), M-MIP(BPB), gave the moderate imprinting factor for BPA. Furthermore, M-MIP(BPB) was applied for the selective extraction and determination of BPA in environmental water samples. The concentration of BPA in river water samples was determined to be 68 ng/L., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The goal of this study was to quantify and demonstrate the dynamic effects of hydraulic retention time (HRT), organic carbon and various components of extracellular polymeric substances (EPS) produced by microorganisms on the performance of submersed hollow-fiber microfiltration (MF) membrane in a hybrid powdered activated carbon (PAC)-MF membrane bioreactor (MBR). The reactors were operated continuously for 45 days to treat surface (river) water before and after pretreatment using a biofiltration unit. The real-time levels of organic carbon and the major components of EPS including five different carbohydrates (D(+) glucose and D(+) mannose, D(+) galactose, N-acetyl-D-galactosamine and D-galactose, oligosaccharides and L(-) fucose), proteins, and polysaccharides were quantified in the influent water, foulants, and in the bulk phases of different reactors. The presence of PAC extended the filtration cycle and enhanced the organic carbon adsorption and removal more than two fold. Biological filtration improved the filtrate quality and decreased membrane fouling. However, HRT influenced the length of the filtration cycle and had less effect on organic carbon and EPS component removal and/or biodegradation. The abundance of carbohydrates in the foulants on MF surfaces was more than 40 times higher than in the bulk phase, which demonstrates that the accumulation of carbohydrates on membrane surfaces contributed to the increase in transmembrane pressure significantly and PAC was not a potential adsorbent of carbohydrates. The abundance of N-acetyl-d-galactosamine and d-galactose was the highest in the foulants on membranes receiving biofilter-treated river water. Most of the biological fouling compounds were produced inside the reactors due to biodegradation. PAC inside the reactor enhanced the biodegradation of polysaccharides up to 97% and that of proteins by more than 95%. This real-time extensive and novel study demonstrates that the PAC-MF hybrid MBR is a sustainable technology for treating river water., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Purpose: Cyclophosphamide (CP) contamination has been detected in Japanese hospitals. In other countries, the surface contamination of CP vials has been reported; however, the manufacturing process of Japanese CP vials is unknown, so the conditions are not necessarily the same as in other countries. This study aimed to establish whether vial surface contamination also occurs in Japan., Method: Contamination of vial surfaces was examined with a wipe test. Urine samples were taken from a pharmacist, engaged solely in dispensing work, for 29 h. It was also investigated whether CP vials were dispensed during the urine sampling period. In addition, vial surfaces, purposely coated with CP and then washed, were examined using wipe tests., Result: CP was detected at 30-60% in vials, which was 11-62 ng (0.10-0.54 ng/cm(2)). One of the urine samples was contaminated (CP 13.5 ng); this was taken on Day 2 (11:35 AM). CP was not detected among the washed vials., Discussion: This study shows that the surface of Japanese CP vials was contaminated and that it was probable that healthcare workers were exposed to CP. CP absorption by the pharmacist was probably due to dermal uptake while dispensing. Washing the vial is considered effective to avoid CP exposure. Manufacturers should be more proactive to prevent contamination and healthcare workers should comply with exposure prevention rules. Cytotoxic drugs should be included in institution monitoring lists.

Authors consider the environmental prospects of using melted waste slag as the aggregate for asphalt pavement. In particular, the enrichment of slag-derived fragments in fine abrasion dust particles originated from slag asphalt concrete and its size dependency were concerned. A series of surface abrasion tests for asphalt concrete specimens, containing only natural aggregates as reference or 30 wt% of substituted slag aggregates, were performed. Although two of three slag-asphalt concretes generated 1.5-3.0 times larger amount of abrasion dust than the reference asphalt concrete did, it could not be explained only by abrasion resistance of slag. The enrichment of slag-derived fragments in abrasion dust, estimated on the basis of the peak intensity of quartz and heavy metal concentrations, had size dependency for all slag-asphalt concretes. Slag-derived fragments were enriched in abrasion dust particles with diameters of 150-1000 μm. Enrichment factors were 1.4-2.1. In contrast, there was no enrichment in abrasion dust particles with diameter less than 75 μm. This suggests that prior airborne-size fragmentation of substituted slag aggregates does not need to be considered for tested slag aggregates when environmental risks of abrasion dust of slag-asphalt pavement are assessed., (Copyright © 2011 Elsevier B.V. All rights reserved.)

AMS (Accelerator Mass Spectrometry) radiocarbon dates for eight potsherds from a single piece of pottery from a wetland archaeological site indicated that charred material from the inner pottery surfaces (5052 ± 12 BP; N = 5) is about 90 (14)C years older than that from the outer surfaces (4961 ± 22 BP; N = 7). We considered three possible causes of this difference: the old wood effect, reservoir effects, and diagenesis. We concluded that differences in the radiocarbon ages between materials from the inner and outer surfaces of the same pot were caused either by the freshwater reservoir effect or by diagenesis. Moreover, we found that the radiocarbon ages of carbonized material on outer surfaces (soot) of pottery from other wetland archaeological sites were the same as the ages of material on inner surfaces (charred food) of the same pot within error, suggesting absence of freshwater reservoir effect or diagenesis.

Although seismic electric signal (SES) has been used for short-term prediction of earthquakes, selectivity of SES still remains as one of the mysterious features. As a case study, we made a numerical simulation based on a 3D finite element method (FEM) on the selectivity of SES observed in the case of the 2000 Izu earthquake swarm. Our numerical results indicated that the existence of conductive channel under Niijima island could explain the reported SES selectivity.

Air-breathing marine animals, including sea turtles, utilise two fundamentally different environments (i.e. sea surface and underwater) during migration. Many satellite telemetry studies have shown travel paths at relatively large spatio-temporal scales, discussing the orientation and navigation mechanisms that guide turtles. However, as travel paths obtained by satellite telemetry only reflect movements at the surface, little is known about movements and orientation ability underwater. In this study, to assess orientation ability both at the surface and underwater, fine-scale 3-D movements of free-ranging loggerhead turtles Caretta caretta were reconstructed by using multi-sensor data loggers. Video systems ('Crittercam') were also used to record the behaviour of the turtles and the visual information surrounding the turtles. During August and October in 2006 and 2007, eight turtles were released from Otsuchi Bay, Japan (39 degrees 20'30N, 141 degrees 56'00E), and a total of 118 h of 3-D movements were reconstructed. Turtles maintained highly straight-line courses (straightness index >0.95) during 41% of the total duration (i.e. 'travelling periods'). During travelling periods, turtles swam continuously, maintaining unidirectional heading throughout dives whereas turtles changed heading remarkably at the surface. Despite highly directional movements during dives, travel direction tended to shift by the end of dives lasting 10 minutes or more. Such deflections seemed to be compensated during subsequent surfacing periods because there was a negative relationship between changes in travel direction arising during dives and subsequent surfacing periods. Therefore, remarkable changes in heading at the surface could be interpreted as direction-searching behaviour. Our results suggested that turtles undertaking directional travel were more dependent on directional information that was reliable at the surface.

A fundamental study on the adsorption of metal elements on Shirasu, a pyroclastic flow deposit distributed in southern Kyushu, Japan, has been conducted. The adsorption experiment was carried out by a batch method, and by using Zn(II) and Cu(II) under several conditions; the effects of the initial concentration of metal ions, grain size, and pH were investigated. At smaller grain sizes, the amount of Zn(II) and Cu(II) adsorbed increased. At higher pH values, the amount of Zn(II) and Cu(II) adsorbed increased. Plots of the adsorption isotherm indicated that the adsorption of Zn(II) and Cu(II) on Shirasu followed the Langmuir isotherm model, and the Langmuir isotherm constants, W(0) and b, were obtained. W(0) at pH 5.0 was approximately two-times larger than that at pH 3.0. This may reflect an increase in the number of anionic binding sites on the surface of Shirasu with an increase in the pH. The b value for Zn hardly changed with an increase in the pH, and for Cu the value decreased with an increase in the pH. These observations suggest that anionic binding sites have a low stability constant, since the apparent stability constant, b, is obtained as the average of stability constant of all sites on the Shirasu surface.

Excessive polyethylene wear is recognized as one of the most important factors affecting the durability of total knee arthroplasty; however, bearing surface wear is a multifactorial problem. The purpose of this study was to identify factors for polyethylene wear and failure in primary posterior cruciate-retaining (PCR) total knee arthroplasty (TKA) in two disparate cohorts (American and Japanese). Seventy-three total knee arthroplasty operations were performed on 48 Japanese patients, and 76 on 63 American patients with noninflammatory arthritides. All patients were evaluated clinically and radiographically using a total joint arthroplasty database. Age, weight, diagnosis, Knee Society patient category, prosthesis size, insert thickness, alignment, polyethylene wear, osteolysis, Knee Society knee score, Knee Society pain score, and radiographic and clinical survivorship were evaluated. Seventy-three Japanese TKAs were followed for a mean of 6.6 years (range, 2.0-10.6). Three (4.1%) Japanese patients required revision. Seventy-six American TKAs were followed for a mean of 9 years (range, 2-10.2). Two (2.6%) American patients required revision. The American patients were significantly older, heavier, male predominant, and required larger size implants. The Japanese patients were significantly more female predominant and had a significantly less postoperative arc of motion. Knee Society knee and pain scores, survivorship, average total polyethylene wear, and annual wear rates were not different among the two cohorts. PCR TKA had similar survivorship in disparate cohorts of Japanese and American total knee arthroplasty patients despite smaller stature patients in the Japanese cohort. Cultural, gender-specific, and morphologic differences need to be considered for knee implant design. However, survivorship and polyethylene wear rates appear to be independent of these factors in disparate populations.

Clinical results of 50 metal-on-metal resurfacing arthroplasties in 45 Japanese patients were evaluated to a minimum follow-up of 5 years. The predominant diagnosis was developmental dysplasia or dislocation of the hip (70%). One patient died of an unrelated cause and another was lost to follow-up. Two hips received revision surgery, including 1 femoral neck fracture and 1 septic loosening. In the remaining 46 hips, 1 hip showed femoral component loosening. Clinical scores of the 46 hips were satisfactory at the final follow-up. The survival rate at 5 years was 96% when failure was attributed to revision for any reason. Metal-on-metal resurfacing arthroplasty in Japanese patients, who have a different distribution of hip diseases from European and American patients, showed similarly promising early clinical results.

Postural responses to challenging situations were studied in older adults as they stood on a foam surface. The experiment was designed to assess the relative contributions made by visual and somatosensory information to the correction of postural sway. Twenty-four subjects, aged 56-83, stood for 20 s on a 1) firm or 2) foam surface with 1) the eyes open or 2) the eyes closed. Centre-of-pressure trajectories under the subjects' feet were measured by using a force platform. A repeated-measure two-way MANCOVA (two surfaces vs. two vision conditions) showed a significant main effect for the surface, but not for the vision. No covariate effect for age was found. Anterior-posterior sway increased in the subjects who were merely standing on the foam surface independent of the vision condition. Medial-lateral sway dramatically increased if the subjects stood on the foam surface with their eyes closed, but not if they stood with their eyes open. These results indicate that older adults rely more on visual information to correct mediolateral postural sway. It appears that the deterioration in visual acuity that occurs with aging may increase the risk of sideway falls, particularly in challenging situations, e.g., when standing on irregular or soft surfaces.

Lyophilized protein formulations sometimes pose problems such as the formation of a cloudy solution upon reconstitution. Ampoule or vial breakage can also occur during the production processes of lyophilized pharmaceutical products. Various efforts have been made to overcome those difficult problems. In this study, we introduce a particular temperature program into the production process of a recombinant human Interleukin-11 (rhIL-11) lyophilized formulation containing sodium phosphates (Na2HPO4/NaH2PO4, pH 7.0) and glycine in an attempt to improve its dissolution properties and to prevent ampoule breakage from occurring. The formulation was pretreated by nucleating ice and maintaining the solution overnight at a temperature of -6 degrees C. The solution was then completely frozen at a lower temperature. This pretreatment proved successful in not only producing a lyophilized cake which readily disintegrated and dissolved in the reconstitution media, but also prevented ampoule breakage from occurring during the production processes. In contrast, a lyophilized cake produced without the pretreatment created a cloudy solution particularly when reconstituted using water for injection contaminated with aluminum (Al3+), although the solution became transparent within 20-30 min. The pretreatment induced the crystallization of sodium dibasic phosphate (Na2HPO4) in the freeze-concentrate whereas direct freezing without the pretreatment did not crystallize the salt. Thermal analyses (DSC and TMA) showed that amorphous sodium dibasic phosphate in the freeze-concentrate became crystallized upon heating, accompanied by an increase in volume, which probably caused the ampoule breakage that occurred without the pretreatment. Although power X-ray diffraction (PXRD) experiments suggested that, with or without the pretreatment, glycine assumed the beta-form and sodium phosphate stayed amorphous in the final products, an electrostatic interaction between dibasic phosphate anions and rhIL-11, a highly cationic protein, would only exist in the lyophilized cake produced without the pretreatment. This interaction is highly likely because aluminum facilitates the formation of a cloudy solution upon reconstitution possibly by using the divalent anions which effectively reduce electrostatic repulsions between aluminum and the protein to form an aggregate structure that is not readily soluble. The pretreatment would circumvent the interaction by crystallizing the sodium salt before freezing creating a relatively soluble lyophilized cake that is much less sensitive to aluminum., (copyright 2004 Elsevier B.V.)

We developed a new fabrication method for standard surface sources by using an inkjet printer with inks in which a radioactive material is mixed to print on a sheet of paper. Three printed test patterns have been prepared: (1) 100mm x 100mm uniformity-test patterns, (2) positional-resolution test patterns with different widths and intervals of straight lines, and (3) logarithmic intensity test patterns with different radioactive intensities. The results revealed that the fabricated standard surface sources had high uniformity, high positional resolution, arbitrary shapes and a broad intensity range.

The aim of the study was to investigate the effect of ethnicity, gender and age on the degree of clenching force and distribution of the load over the dentition. The maximal clenching force was measured in 12 young Danish females, 12 young Japanese females, 12 young Japanese males and 10 senior Japanese males using the Dental Prescale System. The occlusal contact area, average pressure, occlusal load, antero-posterior and right-left location of the occlusal load center (i.e., a center of balance of the occlusal load distributed over the maxillary dentition: OLC) and dental arch length and width were analyzed and compared. The arch width and average pressure in young Danish females were significantly smaller/lower than in Japanese females. The arch length, arch width, contact area and total occlusal load in young Japanese males were significantly greater than those of the Japanese females. The average pressure in young Japanese males was also greater than in senior males. The location of the OLC was almost the same in all groups. The results suggest that the analysis of the OLC may be a useful method for evaluating occlusal function and prosthodontic treatment because the location of the OLC is not affected by ethnicity, gender and age.

Stainless steel wrought wires used as clasp arms for removable partial dentures in Thailand were compared with those used in some other countries (in the as-received condition) in terms of flexibility, Vickers microhardness and composition. The results showed that there were significant differences (P< or =0.05) among the wires. A Japanese stainless steel wire (SK) was obviously different from the others. It had the lowest proportional limit and microhardness, but its flexibility was almost the same. The chemical composition of each wire was not greatly different. The wires were about 18-20 wt% chromium and 8-9 wt% nickel, except for the SK wire, which had about 12 wt% nickel.

Multielement monitoring of the concentrations of trace metals dissolved in surface seawater collected at sampling stations along the ferry track between Osaka and Okinawa was performed by ICP-MS (inductively coupled plasma mass spectrometry). The surface seawater samples were collected by an automated sampling system for on-board sampling, which was installed on the bottom of a ferryboat. A part of each seawater sample was filtered with a membrane filter (pore size of 0.45 microm) immediately after sampling. Both filtered and non-filtered seawater samples were acidified to pH ca. 1 by adding conc. HNO3, and were subjected to chelating resin preconcentration for the determination of trace metals by ICP-MS, where the concentrations of analyte metals in the filtered and non-filtered seawater samples were referred to as the dissolved and total concentrations, respectively. According to the thus-obtained results, it was found that most trace metals, especially below the 0.01 microg l(-1) as the dissolved and total concentrations, sensitively reflected the environmental pollution in the Osaka Bay and Seto Inland Sea area, as well as near to the Bungo Canal and the outlet of Kagoshima Bay.

Removal efficiency of chloroform from tap water by rice bran was investigated. The adsorption rate by rice bran was similar to activated carbon. The amount of chloroform adsorbed was plotted against the equilibrium concentration of chloroform in solution on a logarithmic scale. A linear relationship was obtained, indicating that the adsorption reaction was a Freundlich type. The adsorption of chloroform by rice bran was observed in the range of pH 1-11. Chloroform was successfully removed from tap water with average removal efficiency of 70% after 60 min when rice bran was applied to tap water that contained 0.0064 mg/L chloroform.

A modified ovoid applicator for intracavitary radiotherapy was developed for Japanese and other Asian women. It has more variations of smaller sized ovoids than the original rigid standard applicator of the Selectron-MDR and microSelectron-HDR. In addition, application of the ovoid pair and tandem flange is easy due to the flat surface of the inner aspect of the ovoid pairs, which prevents slippage of the ovoids and flange. The applicator is described together with source loading and dose distribution.

Adhesive test in vitro is performed to evaluate bonding materials. This paper describes methods of measuring adhesion to dentine currently used in Japan, and considers advantages and disadvantages. Various tests are used in Japan. Many factors-dentine substrate, storage conditions, bond strength test method-affect bonding to dentine. Bond strength test methods employed are divided into: tensile bond test and shear bond test. The test method used for the best prediction of clinical performance in bond strength evaluation is discussed. There has also been interest in bonding stability. At present, it may be difficult to propose an optimal standardized measuring method. Standardized experimental conditions in vitro which can simulate conditions in vivo are still under investigation.

In Japan, five types of ventricular assist system, including the government-approved National Cardiovascular Center type and the Tokyo University type, were applied to 202 patients as of September 30, 1991. Adult-sized ventricular assist systems were used in 194 patients and a pediatric one in 8. The major primary diagnosis was ischemic heart disease (52.5%). Sixty-three patients in cardiogenic shock with acute myocardial infarction were treated using a ventricular assist system, and the results were fairly good. The predominant indication was failure to be weaned from cardiopulmonary bypass (72.8%), and there was no case of bridging to heart transplantation. Left ventricular assist was performed in most patients (85.1%). The duration of ventricular assist system application ranged from 1 hour to 70 days, and the mean duration was 6.8 +/- 9.6 days. Duration of circulatory support had no relation to the results, and the longest support in survivors was 25 days. The weaning rate was 50.0%, and the survival rate was 26.2%. Main causes of death were heart failure, including unrecoverable heart failure, and multiple organ failure. It should be kept in mind that the decision to use a ventricular assist system should be made quickly, before major organs, including the heart itself, are irreversibly damaged.

Visual observations were made of 3,202 maxillary first premolars and 3,365 maxillary second premolars from subjects of known sex, age, and side attributes. The material belongs to the Okamoto Research Laboratory of Dentistry. Items observed for each donor included number of dental roots, shapes of root apexes, root grooves, root orientation and curvature, and conditions of the maxillary first and second premolars. Results 1) In 65.7% of all materials (55.4% in males and 76.1% in females), maxillary first premolars had primary single roots. Complete branched roots accounted for 25.5% of the male and 17.6% of the female materials. In both cases, there was significant distinction between the sexes. Triple root teeth were extremely rare in both male- and female-donor teeth, as were double rooted maxillary second premolars. 2) Protruding, circular, and flat root apex types occurred in both maxillary first and second premolars. Circular and flat types were common among males. Branched and double-root maxillary first and second premolars were of either the complete or the incomplete type, both of which were more common in males. 3) About half of the mesial surface grooves in single-root maxillary first premolars were deeper than distal surface grooves in the same teeth: In 1/4-branch double teeth, 28.8% of the mesial surface grooves were deeper than the distal-surface grooves. The corresponding percentage for 1/3-branch double teeth was 38.8%. In 7.6% of 1/4-branch and 17.4% of 1/3-branch double teeth, distal-surface grooves were deeper than mesial-surface grooves. In 36.4% of 1/4-branch double teeth and 28.9% of 1/3-branch double teeth, the lower portion of the root was web shaped. In maxillary first premolars, lingual roots of 1/3-branch double-root teeth were cylindrical, as were 28.9% of buccal roots. Root grooves occurred on the lingual sides of 61.7% of all specimens. For 1/2-branch double root teeth, 18.4% were cylindrical: and 62.7% had grooves on the lingual side. Results are essentially the same in both cases. 4) Straight dental roots occurred in 37.4% of maxillary first and 35.4% of maxillary second premolars. Roots inclined distally in 36.7% of maxillary first premolars and in 18.8% of maxillary second premolars. A variety of inclinations and curvatures was observed. Booth roots were straight in 47.5% of 2-branch maxillary first premolars, whereas 35.1% had 1 straight and 1 inclined root and 84.4% had 2 distally inclined roots.(ABSTRACT TRUNCATED AT 400 WORDS)

Monomers which promote adhesion not only to enamel but also to dentine have been prepared. They have both hydrophilic and hydrophobic groups. The monomers are 2-hydroxy-3-beta-naphthoxypropyl methacrylate, 2-methacryloxyethyl phenyl hydrogen phosphoric acid and 4-methacryloxyethyl trimellitate anhydride. Chemical reaction between monomers and tooth substrates did not lead to adhesion. Cleaning of the ground tooth surface to remove the smeared layer with aqueous 10 per cent citric acid and 3 per cent ferric chloride solution prior to adhesion is recommended. Then, the lipophilic monomers will promote the inter-penetration of monomers into the hard tissues. The infiltrated methacrylates polymerize there and good adhesion takes place. The layer has good resistance against acid and is, in effect, a resin reinforced dentine and enamel as demonstrated by SEM and TEM. The tensile adhesive strength to the cleaned dentine was 18 MN/m2 and to the enamel 14 MN/m2. On the other hand, the value was reduced to 6 MN/m2 when the dentine had been etched by phosphoric acid or citric acid. The ferric chloride added to the citric acid protected dentinal collagen during demineralization. However, the ferric chloride provided ineffective protection against an acid as strong as phosphoric acid. The high bond strength was not dependent upon interlocking at the dentinal tubules as had been considered previously. The resin reinforced dentine and enamel is a hybrid of natural tissue and artificial material and is valuable in the prevention of secondary caries after restoration.

Migration of melamine and formaldehyde into food-simulating solvents from cups made of melamine resin was studied under various conditions. Little migration of melamine was observed in any unused cups kept at 60 degrees C for 30 min, room temperature (26 degrees C) for 1 h or cooled at -20 degrees C for several days. Migration of both compounds was strongly affected by heating and acidity. The highest migration of melamine into 4% acetic acid used as a food-simulating solvent was 42.9 +/- 7.2 ppm when the migration test was repeated seven times at 95 degrees C for 30 min. In this time, the migration of formaldehyde was 14.2 +/- 0.6 ppm into the solvent. The molecular ratio of the migration amount of formaldehyde to melamine decreased according to the formula Y = 9.15X-0.813 over seven repetitions of the test, and was maintained at about 1.6 between the 10th and 20th repetitions. The inner surface of the cups became tarnished during the repetition of the test and their roughness increased from 1 micron before the test to 2.5-5 microns after 20 repetitions of the test. Migration of melamine from the cups being used at a cafeteria was 0.4 +/- 0.5 ppm, but that of formaldehyde was undetectable when the cups were kept at 60 degrees C for 30 min with 4% acetic acid.

Closed and open Japanese nickel titanium (NiTi) alloy coil springs were fabricated from the Japanese NiTi alloy wire. The closed coil springs were subjected to a tensile test and the open coil springs were subjected to a compression test to evaluate the mechanical properties. At the same time, a test with the commercially available steel coil springs also was done. It was clearly established that the Japanese NiTi alloy coil springs exhibited superior springback and super-elastic properties similar to the properties of the Japanese NiTi alloy arch wires. In addition, it was shown that the load value of super-elastic activity can be effectively controlled by changing the diameter of the wire, the size of lumen, the martensite transformation temperature, and the pitch of the open coil spring. The most important characteristic of the Japanese NiTi alloy coil springs is the ability to exert a very long range of constant light, continuous force. It is possible to use this coil selectively to obtain optimal tooth movement.