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Purpose This study aimed to compare two methods of assessing the half-value layer (HVL) for computed tomography scanners in a single-rotation technique with and without lead apertures (SRTLA / SRT). Methods A 0.6 cc real-time ionization chamber was suspended freely in the air at the isocenter, and six sheets of lead (130 × 170 × 2 mm) were placed at the bottom of the gantry cover, forming five apertures each having a width of 16 mm (SRTLA geometry). Four aluminum plates (100 × 100 mm2; 2.0, 4.0, 6.0, and 8.0 mm thick) were placed on these apertures. Air-kerma rate profiles ( K air ) in the spiral mode were measured at tube potentials of 80, 100, 120, and 135 kVp, a tube current of 100 mA, a nominal beam width of 32.0 mm, and a rotation time of 1.5 s. Thereafter, all lead sheets were removed, and these same measurements were taken to investigate the errors of the HVLs (SRT geometry). HVLs using the SRTLA and SRT were compared with those obtained through a conventional localization technique. Results The HVLs measured in the SRTLA/SRT at 80, 100, 120, and 135 kVp were 3.37/3.50, 4.24/4.47, 5.22/5.44, and 5.90/6.17 mm, respectively. The differences between these values and those obtained through the conventional technique were 0.09/0.22, 0.02/0.25, 0.05/0.27, and −0.01/0.26 mm, respectively. Conclusions The accuracies of the HVLs of the SRTLA were similar to those of the conventional technique. The lead apertures under the aluminum plates would help reduce the number of inaccurate HVL measurements.

Is a published research paper an important indicator of successful operational research at programme level in low-income countries? In academia, publishing in peer-reviewed scientific journals is highly encouraged and strongly pursued for academic recognition and career progression. In contrast, for those who engage in operational research at programme level, there is often no necessity or reward for publishing the results of research studies; it may even be criticized as being an unnecessary detraction from programme-related work. We present arguments to support publishing operational research from low-income countries; we highlight some of the main reasons for failure of publication at programme level and suggest ways forward.

脱臼性股関節症に対するTHAは手技が困難で，リハビリにも長期を要する．著明な脚短縮や筋力低下，手術手技が主因である．我々は大腿骨転子下斜め短縮骨切り術を併用してTHAを行った症例を経験したので報告する．症例は71歳女性．股関節脱臼の既往があるも治療を受けることなく，また脚長差があるも痛みがないため放置していた．誘因なく股関節痛が出現し，対症療法を行うも効果がないためTHAを施行した．後方アプローチでS-ROM-Aを用いた．cupを原臼位まで55mm引き下げ，大腿骨を転子下で15mm切除した結果40mmの脚延長となったが，神経麻痺は認めていない．術後6ヶ月で骨癒合は良好,疼痛なく，歩容および股関節周囲の筋力も改善した．脱臼性股関節症に対するTHAでは延長過多による神経障害や大転子切離によるトラブルも多い．転子下斜め短縮骨切り術は回旋安定性および接触面積が広くなり骨癒合にも有利で早期リハビリが可能と思われる．

We constructed and characterized arrayed bacterial artificial chromosome (BAC) libraries of five Drosophila species (D. melanogaster, D. simulans, D. sechellia, D. auraria, and D. ananassae), which are genetically well characterized in the studies of meiosis, evolution, population genetics, and developmental biology. The BAC libraries comprise 8,000 to 12,500 clones for each species, estimated to cover the most of the genomes. We sequenced both ends of most of these BAC clones with a success rate of 91%. Of these, 53,701 clones consisting of non-repetitive BAC end sequences (BESs) were mapped with reference of the public D. melanogaster genome sequences. The BES mapping estimated that the BAC libraries of D. auraria and D. ananassae covered 47% and 57% of the D. melanogaster genome, respectively, and those of D. melanogaster, D. sechellia, and D. simulans covered 94-97%. The low coverage by BESs of D. auraria and D. ananassae may be due to the high sequence divergence with D. melanogaster. From the comparative BES mapping, 111 possible breakpoints of chromosomal rearrangements were identified in these four species. The breakpoints of the major chromosome rearrangement between D. simulans and D. melanogaster on the third chromosome were determined within 20 kb in 84E and 30 kb in 93E/F. Corresponding breakpoints were also identified in D. sechellia. The BAC clones described here will be an important addition to the Drosophila genomic resources.

The inhibition of the contamination of Ru-capped Mo/Si multilayer mirrors was systematically investigated by introducing ethanol into a controlled vacuum that mainly consisted of water vapor. Water vapor was introduced at a pressure of up to 1.3×10-5 Pa, which is a typical pressure in extreme ultraviolet (EUV) lithography production tools. Additionally, ethanol was introduced at several partial pressures ranging from 1.0×10-7 to 3.8×10-5 Pa. At the lowest ethanol pressure, the same degree of reflectance degradation as in the water-only case was observed. However, reflectance degradation was suppressed at ethanol pressures higher than 2.0×10-6 Pa. As a result of surface analyses using X-ray photoelectron spectroscopy, we determined that the reflectance degradation was caused by oxidation. The inhibition of contamination may be caused by a mechanism of a self-limiting carbon layer from ethanol adsorption on a hydroxylated mirror surface. It was found that oxides at the mirror surface were deoxidized by introduced ethanol. Therefore, deoxidization of the Ru layer may be one of the mechanisms of the inhibition of contamination. The suppression of reflectance degradation was independent of the photon intensity and measured for up to 1200 J/mm2. This dose corresponds to about 3 months of operation for projection optics mirrors at the maximum power expected. Therefore, the introduction of ethanol was found to be a promising method for inhibiting the contamination of projection optics mirrors, which are irradiated by a wide range of EUV power.

A new contamination evaluation system that can irradiate high-flux extreme ultraviolet (EUV) and measure, in situ, the reflectivity of multilayer mirrors for EUV lithography (EUVL) projection optics was constructed to develop a contamination inhibition mechanism at the NewSUBARU synchrotron radiation (SR) facility. The vacuum chambers of the systems are all metal sealed. All automatic stages in the system are driven by motors set outside the chambers. The optimum pressure of the chamber was 2 ×10-7 Pa, two orders of magnitude higher than that in the system reported last year. The partial pressure of the hydrocarbon components was also two orders of magnitude smaller than that in the previously reported system. In the first experiment using the system, the lifetime of Si-capped Mo/Si multilayer mirrors was evaluated as a function of water vapor pressure. The system can also be used to measure and map X-ray absorption near-edge structure (XANES) spectra in the irradiated area, which is very important for the in situ evaluation of the contamination mechanism.

【目的】治療に抵抗する仙骨嚢腫にshuntを行ったので報告する．【症例】40歳女性．腰下肢痛のため5分間の坐位が不可．MRIで嚢腫と診断し，保存療法を1ヶ月行うも効果なく，早期復職目的で手術施行．嚢腫とくも膜下腔の間にshunt tube挿入，髄液漏出予防でフィブリン糊を滴下した．1週臥床の後，2週で退院，1ヶ月で復職した．短期だが髄液漏出なく経過良好である．【考察】保存療法が原則であるが，激しい疼痛，知覚障害・筋力低下・排尿障害を伴ったり，治療に抵抗する場合は手術を考慮するべきである．手術には壁の縫縮や焼灼，弁機構開放，周囲神経との癒着剥離，shuntなどがある．症状発現は坐位で腹圧と髄液圧が上がり，チェックバルブにより嚢腫内に髄液が流入し，馬尾や神経根が圧排され，発症したものと思われた．そのため，減圧にて症状改善可能と考えshuntを行った．【まとめ】治療に抵抗する仙骨嚢腫にshuntを行った．短期だが髄液漏出なく経過良好である．

The reflectivity of Ni/Ti supermirror with 3Qc has been enhanced by using ion-polishing technique in combination with an ion-beam sputtering system. The dependencies of ion-polishing time, ion acceleration energy and incidence angle on the interface roughness were firstly studied to optimize the conditions of Ar + ion polishing by using X-ray and neutron reflectometry. Based on the optimal ion-polishing condition, Ni/Ti supermirrors with 3Qc were fabricated and characterized. The reflectivity has been increased, and it reached 87% at the critical angle of total reflection.

We experienced a case of pulmonary embolism after surgical repair patellar ligament avulsed fracture. The patient was a 34-year-old man who fell two meters into a gutter.Two days after the accident, he underwent surgical repair. Operative findings showed that avulsed fragments were comminuted and patellar ligament was detached.The fracture was fixed with two cancellous screws and ligament was repaired by angmentation of soft wire. 16 days after operation, he suffered shock by pulmonary embolism. Diagnosis was performed by venography and emhanced CT, and treatment using a vena cava filter and thrombectomy system. Thrombosis completely disappered and the filter could be removed.

We present a type of lateral shearing interferometer (LSI) for at-wavelength characterization of the projection lens for use in extreme-ultraviolet lithography (EUVL). LSI is one of the potential candidates for high Numerical Aperture (NA) optics testing at the EUV region. To address the problem of multiple-beam interference, we propose a general approach for derivation of a phase-shift algorithm that is able to eliminate the undesired 0th order effect. The main error source effects including shear ratio estimate, hyperbolic calibration, and charge coupled device (CCD) size, etc. are characterized and the measurement accuracy of the LSI is estimated to be within 7 mλ rms (0.1 nm rms at 13.5 nm wavelength) for testing the wavefront of EUVL projection optics.