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Biogas is a promising renewable biofuel, but hydrogen sulfide (H2S) and siloxanes are major obstacles in the conversion of bioenergy from biogas because they damage biogas-processing equipment. This study evaluated two biogas-purification systems for a simultaneous efficient removal of H2S and decamethylcyclopentasiloxane (D5), and compared their economic performance. An acidic biotrickling filter (BTF) was operated continuously for 90 days to investigate its performance under different H2S and D5 concentrations. Meanwhile, commercial iron-oxide-based adsorbents (IOBAs) and activated carbon (AC) were used in adsorption filters for H2S and D5, respectively. The results show that in terms of the ratio of D5 and H2S concentration (RD5:H2S) and pH of the recycling liquid, which are crucial BTF operating parameters, high elimination for both H2S (1.86 kg/(m3·d)) and D5 (0.282 kg/(m3·d)) was achieved at RD5:H2S of 3.7:16 and pH of 0.86. Economic analysis confirmed that BTF-AC was more profitable than IOBA-AC adsorption over a life span of 10 years because the pre-removal of D5 by a BTF significantly decreased the costs of IOBAs and AC, despite BTFs requiring a higher initial capital investment. In terms of the economic benefit of biogas production of 1200 Nm3/h, the competitive annual cost of 90.5 k$/year indicated that BTF was more profitable, yielding both cost saving and the benefit of providing heat. The advantage of BTF-AC adsorption was a more radical D5-abatament, enabling profit by selling the electricity produced from biogas to the grid.

The aim of this study was to investigate the effects of potassium fluoride (KF) and sodium fluoride (NaF) in different concentrations on micro-shear bond strength (µSBS) and their protective effects against acid. The enamel blocks were treated with several concentrations of KF and NaF. For µSBS, Clearfil SE Bond 2 was applied to the treated surface and resin composite was light-cured, then examined using a universal testing machine. For acid resistance test, the specimens were immersed in acidic solution (pH 4.5), then examined under 3D confocal laser scanning microscope (CLSM). In µSBS, KF at 1,000, 9,000, and 10,000 ppm did not show differences compared with the control, while other concentrations of KF and NaF led to decreased µSBS. Higher concentrations of NaF and KF showed higher resistance to the acid challenge. So, we concluded that various concentrations of KF and NaF solutions had specific effects on µSBS and acid resistance.

We studied the phase stability of Ce-substituted magnetoplumbite-type Sr ferrite under various oxygen pressures. We have successfully obtained Ce-substituted samples as revealed from X-ray diffraction and wavelength dispersion X-ray analyses. The solubility limit of Ce in Sr1- x Ce x Fe12O19 was estimated to be $x = 0.24$ at ambient pressure, which is reduced to 0.05–0.10 under higher oxygen pressures. The variation of the $c$ -axis against $x$ and the reduction of the solubility by increasing oxygen pressure suggests that the valence of Ce is not 4+ but 3+. The solubility limit of Ce is dominated not only by the ionic radius but also by the valence instability of Ce.

Of various methods for delivering functional molecules into cells, a chemical approach using cell-penetrating peptides (CPPs) is facile and highly efficient. Currently, however, there are few examples of CPPs highly efficient with bacteria in contrast to CPPs targeting animal cells, and thus our understanding of the structural effects of these bacteria-efficient CPPs, termed as BCPPs, on permeation efficiency is limited. Herein, we report a comprehensive investigation on the permeation efficiencies of cationic short peptides through bacterial cell membranes. We observed that elongating the length of the main chain increased permeation efficiency. More interestingly, the length of the peptide side chain critically affected permeation efficiency; shortening the side chain significantly enhanced efficiency. Among the BCPPs investigated, 2,3-diaminopropionic acid nonamer showed the highest permeation efficiency into bacterial cells of diverse strains, allowing the transport of oligo peptide nucleic acids and subsequent growth inhibition. This study provides insights into the molecular design of efficient BCPPs for manipulating bacterial growth.

Purpose This study was designed to assess working environment preferences of students in the Department of Radiological Technology using conjoint analysis for establishing an efficient medical system. Method We carried a questionnaire survey on working environment preferences for 196 students in the Department of Radiological Technology in Japan. We defined eight characteristics for virtual medical facilities as follows: presence of colleagues who can be consulted, employment status, number of night shift per month, academic meeting participation, number of hospital beds, possession of nuclear medicine imaging systems and radiation therapy systems, location of medical facilities, and change rate in annual income. A total of 18 virtual medical facilities were selected by an orthogonal array table using above-mentioned characteristics. The acquired data by the pairwise comparison method were analyzed by conjoint analysis. Marginal rates of substitution that represent students' preferences were also calculated. Result The factors that influenced their preferences were the following: placement of medical facilities in great city, presence of colleagues who can be consulted, employment status is not non-regular employment, set up of nuclear medicine imaging systems and radiation therapy systems, the number of night shift is twice per month, and attendances at academic meetings. Conclusion In summary, students in the Department of Radiological Technology tend to prefer the facilities with regular employment, great city, presence of colleagues who can be consulted, and possession of nuclear medicine imaging systems and/or radiation therapy systems.

Conventionally, the delivery of biomolecules into bacteria for the generation of characterized or functional mutants has relied greatly on horizontal gene transfer techniques. However, the low compatibility of these techniques with novel or hard-to-transform bacteria currently serves as a challenge to the bioengineering field. Here, we explored the use of cell penetrating peptides (CPPs) as an alternative biomolecule delivery approach by investigating the effects of the abiotic factors during CPP permeation. Using the (KFF)3K-FAM conjugate and Escherichia coli as models, we evaluated four abiotic factors where two of these factors, temperature and solution tonicity, promoted (KFF)3K-FAM permeation efficiency. Our data show that optimal (KFF)3K-FAM permeation efficiency was achieved for E. coli at approximately 98.1% under conditions of 37°C (growth optimal temperature) and 50% PBS concentration. Based on these conditions, we subsequently tested the applicability of CPP permeation in various bacterial strains by treating 10 bacterial strains from the Enterobacteriaceae family among which seven strains have no CPP permeation records with (KFF)3K-FAM. Interestingly, when compared with non-optimized conditions, all 10 strains showed a marked increase in CPP permeation ranging between 20 and 90% efficiency. Although using strains within Enterobacteriaceae that are phylogenetically close, our results hinted on the possibility that with proper optimization of the abiotic factors, CPPs could be compatible with a broad range of bacterial strains. Our efforts suggest that CPP could serve as an effective alternative approach for mutant generation and for biomolecule delivery into novel or hard-to-transform bacteria.

The purpose of this study was to investigate the formation of acid-base resistant zone (ABRZ) of enamel surface during bracket bonding by using three self-etch adhesives presently available in the orthodontic treatment. Also, the relation between the thickness of the ABRZ and bonding strength, the relation between the thickness of the ABRZ and the concentration of fluoride ions contained in the adhesives, were discussed respectively. The ABRZ was formed with all self-etch orthodontic adhesives. ABRZ thicknesses of two self-etch adhesives were approximately 0.8-1.0 μm, whereas ABRZ thickness of other one was about 0.1 μm. The bond strengths of all self-etch orthodontic adhesives indicated over 10 MPa, and ABRZ thickness observed in the enamel surface seemed to have no influence to the bond strengths among self-etch adhesives. Moreover, the thickness of ABRZ appeared to be associated with the amount of fluoride ion released from the primer.

SUMMARY In this laboratory study, the microtensile bond strengths (μTBS) of resin-modified glass ionomer cement (RM-GIC) to sound and artificial caries–affected bovine root dentin (ACAD) using three different conditioning agents were evaluated after 24 hours and three months. The fractured interface was examined with a scanning electron microscope (SEM). Specimens were created on bovine root dentin that was embedded in epoxy resin. For the ACAD specimens, artificial carious lesions were created. The RM-GIC (Fuji II LC) was applied either directly (no treatment), after application of self conditioner, cavity conditioner, or 17% ethylenediamine tetraacetic acid (EDTA) applied for 60 seconds, on sound dentin and ACAD, then light cured. They were stored in artificial saliva for 24 hours or three months. Following this, the specimens were cut into sticks for the μTBS test, and the failure mode of the debonded specimens was examined by using SEM. Pretest failures were excluded from the statistical analysis of the μTBS values because of their high incidence in some groups. Results showed that the μTBS values were significantly affected by the dentin substrate as well as the conditioning agent. Self conditioner provided the highest and most stable μTBS values, while cavity conditioner showed stable μTBS values on sound dentin. Both self conditioner and cavity conditioner had significantly higher μTBS values than the no treatment groups. EDTA conditioning reduced the μTBS after three months to sound dentin, while it showed 100% pretest failure with ACAD for both storage periods.

Modern adhesive systems have been developed for enhanced mechanical and antibacterial properties; however, no such systems contain a calcium source to enhance bond strength. Therefore, we evaluated the effect of an experimental calcium-containing primer (10 wt% CaCl2) in two-step self-etching adhesive systems on micro-tensile bond strength (μ-TBS) and acid resistance in dentin adhesive interface observations after acid-challenge using scanning electron microscopy. Using two types of primers and bonding agents (Clearfil SE Bond primer (SEP), experimental calcium-containing primer (CaP), Clearfil SE Bond (SEB), and Clearfil Protect Bond), we prepared four experimental groups. The μ-TBS of CaP-SEB did not differ from that of SEP-SEB. Meanwhile, the CaP groups showed a thicker acid-base resistance zone. Thus, two-step self-etching adhesive system composed of experimental calciumcontaining primer can be used as an adhesive system with high acid resistance and acceptable bond strength.

This study evaluated the effect of two hemostatic agents on bond strength of resin-modified glass ionomer cement (RMGIC) to root dentin after using different pretreatment solutions compared to resin composite with a 2-step self-etch adhesive. Dentin specimens were either uncontaminated or contaminated with a ferric sulphate or aluminum chloride astringent, RMGIC was applied after conditioning with; Cavity Conditioner, Self Conditioner or Clearfil SE Primer, while a resin composite was bonded using Clearfil SE Bond. Microtensile bond strength (μTBS) values and failure modes were determined. Two-way ANOVA revealed that hemostatic agents did not significantly affect the RMGIC bond strength with any conditioning material (p>0.05). SE Primer pretreatment provided the highest μTBS values among RMGIC groups. For the resin composite, ferric sulphate astringent significantly reduced μTBS value (p≤0.001). Scanning electron micrographs of representative dentin surfaces contaminated with the hemostatic agents showed effects on smear layer removal and dentinal tubule occlusion.

The objective was to evaluate the effect of application of silver diamine fluoride (SDF) on discoloration of demineralized dentin over time. Dentin specimens were divided into four groups according to time of dentin demineralization. A 38% SDF solution was then applied to the dentin surfaces. Half of the specimens were placed in light-proof boxes while the remainder were exposed to light. Both groups were maintained at 37˚C. Color change was determined using a spectrophotometer at different time intervals. SEM/EDS analysis were also undertaken. The 13 h EDTA demineralized group showed the highest values for color change among different time intervals, with the control being the lowest. The light exposed groups showed more color change compared to the unexposed groups. We concluded that the degree of dentin demineralization leads to a significant increase of the rate of dentin color change after application of SDF.

Background: Enamel mineral density is dependent on a balanced dynamic process of demineralization and remineralization. Objective: We evaluated the remineralization potential of experimental calcium- containing primer (CaP) application on enamel subsurface lesions. Methods: Demineralized enamel samples obtained from bovine incisor teeth were prepared and cut buccolingually. All samples were divided into 4 main groups according to the type of primer: CLEARFIL SE BOND 2 Primer (SEP), experimental calcium-containing primer (CaP) and bond: CLEARFIL SE BOND 2 Bond (SEB), CLEARFIL Protect Bond (PBB) treatment: (1) SEP-SEB (2) SEP-PBB (3) CaP-SEB (4) CaP-PBB. Each group was subdivided according to storage time in artificial saliva: immediately, 1 month and 6 months. Then, the samples were analyzed using transverse micro radiography (TMR). Additionally, the samples treated with each primer were prepared for scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) observation. Two-way ANOVA was used for the statistical analysis of mineral loss (&Delta, Z: vol%&middot, &micro, m). Results: CaP-PBB had the significantly lowest &Delta, Z at all storage times, while SEP-SEB had the highest &Delta, Z (p &lt, 0.05). SEM observations revealed that new crystals were formed on the surface after 6 months, and the ratio of calcium on the enamel increased in the EDS analysis. Conclusion: Experimental calcium-containing primer can provide additional mineral deposition, with even further deposition when combined with a fluoride-containing bond.

The purpose of this study was to evaluate the early tensile bond strengths of three different resin cements; Super Bond C&B (conventional and quick type) and ResiCem to a CAD/CAM composite block. A CAD/CAM composite block (Shofu Block HC) was ground and silanized according to the manufacturers' instructions before cementation. A conventional tensile bond strength test (O: 4 mm) was performed 10 min, 1 h and 24 h after bonding. Super Bond C&B (quick type) showed the highest bond strength at 24 h. However, results of a three-point bend test showed the mechanical properties were weaker for the Super Bond C&B cements compared with composite cement, Resicem. The 4-META/MMA-TBB resin is a suitable resin cement to bond to a CAD/CAM composite block.

FCP-COMPLEX is a newly developed solution containing fluoride, calcium, and phosphoric acid that has the potential to reinforce caries-affected dentin. This study evaluated the effect of FCP-COMPLEX on micro-tensile bond strength (µTBS) and acid-challenge at the dentin-adhesive interface. FCP-COMPLEX, 2% NaF, and distilled water were applied to artificial caries-affected dentin (ACAD) and the effect on acid-induced damage after resin composite restoration was observed. Scanning electron microscopy and X-ray absorption fine structure (XAFS) were used to evaluate tooth morphology. The µTBS test revealed no effect of FCP-COMPLEX either immediately or after 3 months' storage. The area of acid damage in caries-affected dentin was reduced by FCP-COMPLEX. XAFS analysis revealed that absorbed fluorine on the surface would form CaF2. In conclusion, FCP-COMPLEX significantly reduced the damage of acidic attack at the ACAD-adhesive interface, while the µTBS value was maintained after storage.

Enamel wear, which is inevitable due to the process of mastication, is a process in which the microcracking of enamel occurs due to the surface contacting very small hard particles. When these particles slide on enamel, a combined process of microcutting and microcracking in the surface and subsurface of the enamel takes place. The aim of this study was to detect microscopic differences in the microcrack behavior by subjecting enamel specimens derived from different age groups (immature open-apex premolars, mature closed-apex premolars, and deciduous molars) to cycles of simulated impact and sliding wear testing under controlled conditions. Our findings indicated that the characteristics of the microcracks, including the length, depth, count, orientation, and relation to microstructures differed among the study groups. The differences between the surface and subsurface microcrack characteristics were most notable in the enamel of deciduous molars followed by immature premolars and mature premolars whereby deciduous enamel suffered numerous, extensive, and branched microcracks. Within the limitations of this study, it was concluded that enamel surface and subsurface microcracks characteristics are dependent on the posteruptive age with deciduous enamel being the least resistant to wear based on the microcrack behavior as compared to permanent enamel.

A resin coating technique has been widely advocated in recent years. A combination of a dentin bonding system and a flowable composite is applied on the exposed dentin surfaces immediately after tooth preparation and before taking the final impression. The resin coating is beneficial to both minimize pulpal irritation and enhance the bond strength of a resin cement to dentin. Recently introduced thin-film coating materials based on all-in-one adhesive technology are used for resin coating of crown restorations. Thin-film coating materials can be applied in a single clinical procedure and followed by created a barrier-like film layer on the prepared dentin. Therefore, the resin coating technique may play an important role to protect the dentin phys- ically, chemically, and biologically. The coating materials also have the potential to cover exposed sound enamel and dentin, leading to maximum tooth structure preservation.

Although arachnoid cysts (ACs) are associated with chronic subdural hematomas (CSDHs), especially in young patients, the detailed features of CSDHs associated with ACs remain poorly understood. The objective of this study was to clarify the relationship between the location of CSDHs and ACs and the significance of ACs in young patients with CSDHs. We retrospectively assessed 605 consecutive patients 7 years of age and older who were diagnosed with a CSDH between 2002 and 2014. Twelve patients (2%) had ACs, and 10 of the 12 patients were 7–40 years of age. Patients with ACs as a complication of CSDHs were significantly younger than those without ACs (p < 0.05). Three different relationships between the location of CSDHs and ACs were found: a CSDH contacting an AC, an ipsilateral CSDH apart from an AC, and a CSDH contralateral to an AC. In 21 patients with CSDHs who were 7–40 years of age, 10 (47.6%) had ACs (AC group) and 7 (33.3%) had no associated illnesses (non-AC group). All 10 young patients with ACs showed ipsilateral CSDHs including a CSDH apart from an AC. All 17 patients in both the AC and non-AC groups showed headache but no paresis at admission. The pathogenesis of CSDHs associated with ACs may be different among the three types of locations. The clinical characteristics of patients with a combination of a CSDH and an AC including headache as a major symptom may be attributed to young age in the majority of patients with ACs.

The purpose of this study is to assess working environment preferences of radiological technologists using conjoint analysis. We carried a questionnaire survey on working environment preferences for 200 radiological technologists working in medical facilities in Japan. We defined eight characteristics for virtual medical facilities as follows: presence of colleagues who can be consulted, employment status, number of overtime work per month, academic meeting participation, number of hospital beds, presence of nuclear medicine imaging systems and radiation therapy systems, location of medical facilities, and change rate in annual income. A total of 18 virtual medical facilities were selected by an orthogonal array table using above-mentioned characteristics. The acquired data by the pairwise comparison method were analyzed by conjoint analysis. Marginal rates of substitution between income and non-pecuniary characteristics, which represent radiological technologists' preferences, were also calculated. The factors influenced on their preferences were the following: employment status is not part-time, medical facility is smaller in scale, nuclear medicine imaging systems and radiation therapy systems are set up, and the number of overtime work is less. It was suggested that radiological technologists have a tendency to avoid increase of workloads and select his/her working place with emphasis on own experiences.

FCP-COMPLEX is a newly-developed solution that contains fluoride, calcium, and phosphoric acid. It has the potential to reinforce caries-affected dentin. The purpose of this study was to evaluate the effect of FCP-COMPLEX on the morphology of bovine artificial caries-affected dentin (ACAD). FCP-COMPLEX, 2% sodium fluoride solution, and distilled water were applied to bovine ACAD and the effect on acid-induced damage was observed. Scanning electron microscopy was used to evaluate morphology after acid application. Energy dispersive X-ray spectroscopy was used for mapping and quantitative analyses of the dentin surface, and for line analysis of dentin-adhesive interface. The FCP-COMPLEX precipitated on the dentin surface and fluoride, calcium, and phosphorus were detected at a higher level in the FCP-COMPLEX group. The area of acid damage in caries-affected dentin was reduced by FCP-COMPLEX. In conclusion, FCP-COMPLEX significantly increased the deposition of fluoride onto bovine ACAD and inhibited demineralization.

Part-of-speech (POS) tagging for morphologically rich languages such as Arabic is a challenging problem because of their enormous tag sets. One reason for this is that in the tagging scheme for such languages, a complete POS tag is formed by combining tags from multiple tag sets defined for each morphosyntactic category. Previous approaches in Arabic POS tagging applied one model for each morphosyntactic tagging task, without utilizing shared information between the tasks. In this paper, we propose an approach that utilizes this information by jointly modeling multiple morphosyntactic tagging tasks with a multi-task learning framework. We also propose a method of incorporating tag dictionary information into our neural models by combining word representations with representations of the sets of possible tags. Our experiments showed that the joint model with tag dictionary information results in an accuracy of 91.38% on the Penn Arabic Treebank data set, with an absolute improvement of 2.11% over the current state-of-the-art tagger.