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We developed a predictive model for activities and outbreaks of female Aedes albopictusSkuse, using meteorological data. The number of Ae. albopictuscollected from human bait-sweep net collection (h-BNC) surveillance, conducted by the local government between 2010 and 2019 in Japan, was adopted as a mosquito-activity indicator. The best model was composed of the backward cumulative and backward moving mean of meteorological data (parameters that were measured daily include mean, maximum, and minimum temperature, mean humidity, amount of precipitation, maximum wind speed, and sunshine hours). The root mean squared error (RMSE) and the coefficient of determination (R2) of the best model for the test set, which was not included in the training dataset, were 1.33 and 0.74, respectively. The best model was applied to predict the number of Ae. albopictusobtained from our own h-BNC surveillance in Okazaki City, Japan. RMSE and R2of the results were 1.17 and 0.92, respectively. The present model, using publicly available meteorological values, can predict the collection number of adult Ae. albopictususing h-BNC surveillance thereby providing information to control mosquito activities and outbreaks. Therefore, it may be possible to mitigate the risk of mosquito-borne infections and secondary adverse effects of mosquito bites, such as infectious impetigo and deterioration of the quality of life.

The physical distribution needs of industry and consumers in Japan have evolved since the last half of the 1980s. Just-in-time (JIT) and just-on-lot (matching capacity and handling technology to goods being moved) systems constitute two of the more advanced distribution systems which have been established to meet changing consumer and industrial needs more effectively. However, at the same time, these new systems have led to lower transportation efficiency, traffic congestion and degradation of the environment. Although these advanced physical distribution systems produce negative social and economic impacts, they are still pursued as manufacturers and consumers are service oriented. Industries have been unable to realize the full benefits of the systems because of congestion. Therefore, government and industries should work to reduce the negative effects and institute measures to further promote advanced physical distribution systems. (Reprinted by permission of the publisher.), I. Introduction The diseconomies created by the physical distribution system in large Japanese cities have become critical. This issue has attracted attention since the mid 1960s and has generated numerous [...]

The authors conducted droplet evaporation experiments of light cycle oil (LCO) at various ambient temperatures and pressures. Five kinds of LCO and three kinds of arranged fuels were used. We investigated the evaporation characteristics of LCO and the relationships between the evaporation characteristics and the cetane index. In addition to that, a surrogate fuel composed of four chemical species, which can simulate the droplet evaporation characteristics of LCO, was suggested. Experimental results show that the differences in droplet lifetime between fuel species become larger with decreasing ambient temperature. This is because the low volatile component made the evaporation rate outstandingly slow at a low ambient temperature. It was found that the relationship between droplet lifetime and the late-stage distillation temperature becomes stronger at low ambient temperature and high ambient pressure. By an analysis employing the properties of chemical species in LCO surrogate fuel, it is clarified that the mass evaporation rate becomes smaller than the internal diffusion, which is the condition similar to that in the distillation test. Finally, the relationship between the droplet lifetime and the cetane index was investigated. It can be concluded that the droplet lifetime is independent of the cetane index under all conditions tested in this study. The experimental data obtained by this research can be utilized for the validation of multicomponent fuel droplet evaporation models in the future.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.amjsurg.2006.06.030 Byline: Hisamitsu Zaha (a), Susumu Inamine (a), Takashi Naito (b), Hiroshi Nomura (b) Keywords: Laparoscopy; Omental flap; Breast reconstruction Abstract: Breast cancer surgery and accompanying breast reconstruction have been diversified. We report our experience of immediate breast reconstruction using laparoscopically harvested omental flap (LHOF). Author Affiliation: (a) Department of Surgery, Nakagami Hospital, 6-25-5 Chibana, Okinawa, 904-2195, Japan (b) Department of Plastic and Reconstructive Surgery, Nakagami Hospital, Okinawa, Japan Article History: Received 31 March 2006; Revised 12 June 2006

An evaluation of the first phase of development of dispersed-type battery energy storage technology showed that the technology required for moving to the second phase has been achieved. This second step involves increasing the scale of the batteries. Results of the midterm evaluation showed that most of the batteries met performance targets following load factor, current voltage property and short circuit tests. Research will now be conducted on the manufacture of larger-sized and modular batteries.

Genetically encoded calcium indicators for visualizing dynamic cellular activity have greatly expanded our understanding of the brain. However, owing to the light-scattering properties of the brain, as well as the size and rigidity of traditional imaging technology, in vivo calcium imaging has been limited to superficial brain structures during head-fixed behavioral tasks. These limitations can now be circumvented by using miniature, integrated microscopes in conjunction with an implantable microendoscopic lens to guide light into and out of the brain, thus permitting optical access to deep brain (or superficial) neural ensembles during naturalistic behaviors. Here we describe steps to conduct such imaging studies using mice. However, we anticipate that the protocol can be easily adapted for use in other small vertebrates. Successful completion of this protocol will permit cellular imaging of neuronal activity and the generation of data sets with sufficient statistical power to correlate neural activity with stimulus presentation, physiological state and other aspects of complex behavioral tasks. This protocol takes 6–11 weeks to complete.

Biological Monitoring Method for Urinary Neonicotinoid Insecticides Using LC‐MS/MS and Its Application to Japanese Adults: Jun UEYAMA, et al. Department of Pathophysiological Laboratory Sciences, Field of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine— Agricultural use of neonicotinoid (NEO) insecticides has been increasing in recent years, but their biological monitoring methods have been scarcely reported. In this study, we developed and validated a rapid and sensitive method for quantifying urinary NEO concentrations using high‐performance liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). After phosphate‐induced acidification of a urine sample, urinary NEOs were trapped by a solid‐phase extraction column and eluted with methanol for acetamiprid, imidacloprid, thiacloprid, thiamethoxam, clothianidin and dinotefuran and with an acetonitrile and methanol solution (1:1, v/v) containing 5% NH3for nitenpyram. Aseparation analysis was performed by LC‐MS/MS within 10 minutes for the sample. This method was applied to first morning urine obtained from 52 Japanese (40.9 ± 10.5 years old, mean ± standard deviation) without occupational NEO exposure. The linear dynamic ranges and their limit of quantification (LOQ, signal to noise ratio=10) levels were 0.3−20 or 50 μg/l(r=0.998−0.999) and 0.05−0.36 μg/l, respectively. The absolute recovery was 64−95%, and the intra‐ and inter‐day precisions were less than 16.4% (relative standard deviation, %RSD). This method was successfully applied for analysis of NEOs in human urine samples obtained from 52 adults. The frequencies of individuals who showed more than LOD levels was above 90% for imidacloprid, thiamethoxam, clothianidin and dinotefuran, more than 50% for acetamiprid and thiacloprid and 29% for nitenpyram. These results indicated that our new method could be applied to biological monitoring of NEO exposure even at environmental exposure levels in Japanese adults without occupational spraying histories.

Conditioned fear is extinguished if a conditioned animal receives the conditioned stimulus without an unconditioned stimulus. The extinguished fear response can be reinstated after the animal experiences a mild unconditioned stimulus. Although extensive studies on the neuronal circuitry and neurochemical mechanisms leading to fear acquisition and extinction have been carried out, few studies have focused on reinstatement. In this study, we investigated the effects of N-methyl-D-aspartic acid receptor (NMDAR) antagonists, protein synthesis inhibitors, cannabinoid receptor type 1 (CB1R) antagonists, and benzodiazepine on reinstatement of conditioned fear in mice. An intraperitoneal injection of the NMDAR antagonist MK-801 or the protein synthesis inhibitor anisomycin before the reminder shock attenuated fear reinstatement tested the next day. However, anisomycin had no effect on fear reinstatement tested 2 h after the reminder shock. CB1R antagonists, SR141716, and a benzodiazepine, diazepam, had no effect on fear reinstatement. These results suggested that NMDAR and protein synthesis-dependent plasticity contributed toward the reinstatement of conditioned fear and that protein synthesis was involved in consolidation of reinstated fear.

Several studies have demonstrated the mechanisms involved in memory persistence after learning. However, little is known about memory persistence after retrieval. In this study, a protein synthesis inhibitor, anisomycin, was infused into the basolateral amygdala of mice 9.5 h after retrieval of contextual conditioned fear. Anisomycin attenuated fear memory after 7 d, but not after 2 d. In contrast, infusion of anisomycin 5- or 24-h post-retrieval was ineffective. These findings indicate that anisomycin attenuates the persistence of reactivated fear memory in a time-dependent manner. We propose that late protein synthesis is required for memory persistence after retrieval.

In rats and mice, the hippocampus lies beneath higher than 1 mm of the neocortex. This anatomical feature makes it difficult to experimentally access the hippocampus from the surface of the brain in vivo. This problem may be solved by surgical removal of the cortical tissue above the hippocampus; however, it has not been examined whether this ‘hippocampal window’ surgery preserves the normal hippocampal function. We bilaterally aspirated the posterior parietal cortex above the dorsal hippocampus of adult male mice. These mice still exhibited normal local field potentials of the hippocampus, normal motor activity, and normal cognitive ability in the water-maze test and contextual fear conditioning, compared with intact or sham-operated controls. Thus, exposed hippocampal preparations provide a useful experimental model to study the physiology of the hippocampus.

Recent advances in endoscopic surgery have allowed laparoscopic harvesting of the omental flap with reduced donor-site morbidity and deformity. Between August of 2004 and May of 2010, the authors performed immediate breast reconstruction with the free omental flap in 10 breast cancer patients, employing it either as a pedicle flap or as a free flap for volume replacement. Only one complication occurred during the follow-up. Cosmetic results were mostly satisfactory. The free omental flap is a safe procedure with minimal donor-site morbidity and deformity and can be an additional option for immediate partial breast reconstruction after breast-conserving surgery.

Homer1a, an activity-dependent induced member of the scaffold protein family Homer, plays an essential role in synaptic reorganization and is widely used as a neuronal activity marker. However, the cell type transcribing Homer1aremains unidentified. Here, we investigated the main cell types of the amygdala, hippocampus, primary somatosensory cortex, and dorsal striatum that express Homer1a. Homer1aexpression relevant to the baseline neural activity as well as exposure to unfamiliar and conditioned contexts was preferentially detected in the excitatory neurons within the basolateral amygdala, hippocampus, and neocortex, and in inhibitory neurons within the central amygdala and dorsal striatum. These findings indicate that Homer1ais expressed in the principal neurons of each region regardless of whether they are excitatory or inhibitory neurons.

Completer polarimetry for immersion lithography equipment that comprises Stokes polarimetry of illumination and Mueller matrix polarimetry of projecting optics had been established. It was found that illumination and projecting optics were slightly different from our expectation. These differences might affect optical proximity correction and source mask optimization. However, no lithographer can desterilize parameter sets from the polarimetry for the use of lithography calculation because of their formats, Stokes parameters and Mueller matrix. Conventional lithography simulators require the Jones vector and Jones matrix only. When the illumination was partial polarization or the projecting optics was partially polarizing or partially depolarizing, the Jones calculus cannot support these situations. The Mueller calculus is needed for the case that involves polarizationdepolarization and depolarization-polarization translations. Previous works showed that actual un-polarization of illumination was somewhat polarized in the scan (y) direction and an actual catadioptric projecting optics has a little degrees of polarizance in the slit (x) direction. On the other hand, if you took the aberration effects into the lithography calculation, you had to use the Jones calculus. Therefore, for the lithography calculation with actual polarization data as well as actual aberration data, a special technique is required to handle these data. This paper describes how to physically convert Stokes parameters, which are multiplied by a general Mueller matrix, into Jones vectors. This method permits us to use the actual polarization data to the lithography calculation.

During the development of central nervous system, radial glial cells support target-specific neuronal migration. We recently reported that after implantation of chitosan channels with complete spinal cord transection, the tissue bridging the spinal cord stumps contained axons and radial glial cells. The purpose of this study was to clarify the role of the radial glial cells in the tissue bridges. Chitosan channels were implanted in rats with thoracic spinal cord transection. After 14 weeks, all animals had tissue bridges in the channels that contained many radial glial cells in longitudinal arrangement, some of which were in contact with axons in the bridges. We suggest that radial glial cells can guide regenerating axons across the bridge in the channel after spinal cord transection.

The discovery that palladacycles are efficient catalysts for the allylic imidate rearrangement has resulted in the successful application of several such complexes to this reaction based on planar chiral iron and cobalt containing metallocenes. These palladacycles enable the efficient and highly enantioselective synthesis of a wide variety of protected allylic amines, which are valuable building blocks for use in asymmetric synthesis.

Transplantation of neural stem and progenitor cells (NSPCs) is a promising strategy for repair after spinal cord injury. However, the epicenter of the severely damaged spinal cord is a hostile environment that results in poor survival of the transplanted NSPCs. We examined implantation of extramedullary chitosan channels seeded with NSPCs derived from transgenic green fluorescent protein (GFP) rats after spinal cord transection (SCT). At 14 weeks, we assessed the survival, maturation, and functional results using NSPCs harvested from the brain (brain group) or spinal cord (SC group) and seeded into chitosan channels implanted between the cord stumps after complete SCT. Control SCT animals had empty chitosan channels or no channels implanted. Channels seeded with brain or spinal cord–derived NSPCs showed a tissue bridge, although the bridges were thicker in the brain group. Both cell types showed long-term survival, but the number of surviving cells in the brain group was approximately five times as great as in the SC group. In both the brain and SC groups at 14 weeks after transplantation, many host axons were present in the center of the bridge in association with the transplanted cells. At 14 weeks astrocytic and oligodendrocytic differentiation in the channels was 24.8 and 17.3, respectively, in the brain group, and 31.8 and 9.7, respectively, in the SC group. The channels caused minimal tissue reaction in the adjacent spinal cord. There was no improvement in locomotor function. Thus, implantation of chitosan channels seeded with NSPCs after SCT created a tissue bridge containing many surviving transplanted cells and host axons, although there was no functional improvement.

Thermal curing reactions of oxetane resins {mixtures of novolac type oxetane (PNOX) with 2,2'-bis{(3-ethyl-3-oxetanyl)methoxy}biphenyl (2,2'-BPOX) and mixtures of tris{4-[(3-ethyl-3-oxetanyl)methoxy]phenyl}methane (THPMOX) with 2,2'-BPOX with active diester, 4,4'-isopropylidenebis(2,6-dichlorophenyl diacetate) (IBDCPA) were examined using certain quaternary phosphonium salts as catalysts. The thermal curing reaction of oxetane resins with IBDCPA proceeded smoothly at 170–190 °C to produce insoluble gel products. However, the rate of gel production was strongly affected by catalyst concentration and reaction temperature, and gel products were obtained in the highest yield when the reaction was carried out at 190 °C in bulk using 7 mol % of tetraphenylphosphonium chloride (TPPC) as a catalyst. The glass transition temperatures (Tg)s and 5 weight-% of loss temperatures (Td5%)s of the resulting gel products were determined by DSC and TGA analysis, and it was found that their Tgs and Td5%s were 97–118 °C and 374–380 °C, respectively, when the thermal curing reaction of oxetane resins PNOX/2,2'-BPOX with equivalent amount of cross-linker IBDCPA was performed using TPPC as a catalyst in bulk. On the other hand, the Tgs and Td5%s of gel products obtained from the reaction of oxetane resins THPMOX/2,2'-BPOX with IBDCPA using the same catalyst were 96–128 °C and 381–386 °C, respectively.

The aim of this study was to understand the survival and differentiation of neural stem/progenitor cells (NSPCs) cultured on chitosan matrices in vivo in a complete transection model of spinal cord injury. NSPCs were isolated from the subependyma of lateral ventricles of adult GFP transgenic rat forebrains. The GFP-positive neurospheres were seeded onto the inner lumen of chitosan tubes to generate multicellular sheets ex vivo. These bioengineered neurosphere tubes were implanted into a completely transected spinal cord and assessed after 5 weeks for survival and differentiation. The in vivo study showed excellent survival of NSPCs, as well as differentiation into astrocytes and oligodendrocytes. Importantly, host neurons were identified in the tissue bridge that formed within the chitosan tubes and bridged the transected cord stumps. The excellent in vivo survival of the NSPCs coupled with their differentiation and maintenance of host neurons in the regenerated tissue bridge demonstrates the promise of the chitosan tubes for stem cell delivery and tissue regeneration.

Dimeric palladacycles, di‐μ‐X‐bis[{η5‐(S)‐(pR)‐2‐[2′‐(4′‐methylethyl)oxazolinyl]cyclopentadienyl,1‐C,3′‐N}(η4‐tetraphenylcyclobutadiene)cobalt]dipalladium (COP‐X), containing bridging groups X=OAc, Cl, Br, I, O2CCF3, p‐O2CC6H4F, were synthesised and compared as catalysts for the asymmetric allylic imidate rearrangement of (E)‐Cl3CC(NH)OCH2CHCHR with R=nPr. The enantiomeric excess of the product (S)‐Cl3CC(O)NHCHRCHCH2was essentially invariant of X (93–96 %) and the yield increased in the sequence I

This article reviews bioengineered strategies for spinal cord repair using tissue engineered scaffolds and drug delivery systems. The pathophysiology of spinal cord injury (SCI) is multifactorial and multiphasic, and therefore, it is likely that effective treatments will require combinations of strategies such as neuroprotection to counteract secondary injury, provision of scaffolds to replace lost tissue, and methods to enhance axonal regrowth, synaptic plasticity, and inhibition of astrocytosis. Biomaterials have major advantages for spinal cord repair because of their structural and chemical versatility. To date, various degradable or non-degradable biomaterial polymers have been tested as guidance channels or delivery systems for cellular and non-cellular neuroprotective or neuroregenerative agents in experimental SCI. There is promise that bioengineering technology utilizing cellular treatment strategies, including Schwann cells, olfactory ensheathing glia, or neural stem cells, can promote repair of the injured spinal cord. This review is divided into three parts: (1) degradable and non-degradable biomaterials; (2) device design; and (3) combination strategies with scaffolds. We will show that bioengineering combinations of cellular and non-cellular strategies have enhanced the potential for experimental SCI repair, although further pre-clinical work is required before this technology can be translated to humans.

A two-dimensional numerical analysis with elementary reactions including ion-molecule reactions has been performed to investigate the effect of energy deposition schedule on the minimum ignition energy in the composite spark ignition of methane/air mixtures. The chemical reaction scheme for a methane/air mixture, which has 27 species including 5 ion molecules and electrons and 81 elementary reactions with ion-molecule reactions, is employed in the calculation. Experiments are also carried out, and a qualitative comparison between experiment and calculation is made. The calculated result showed that the optimum ratio of capacity spark energy, for which the minimum ignition energy has a lowest value, exists. The increase in the capacity spark energy leads to a decrease in the formation of radicals during the spark discharge, while it also leads to an active reaction after spark discharge, which is due to the enhanced supply of the unburned mixture into the flame kernel by the inward flow along electrodes. The qualitative trend of calculated and experimental results shows good agreement for the relationship between the ratio of capacity spark energy and the minimum ignition energy. The minimum ignition energy obtained from the calculation with ion-molecule reactions is slightly larger than that without ion-molecule reactions. This may be due to the consumption of energy for ionization.

Techniques for measurement of higher-order aberrations of a projection optical system in photolithographic exposure tools have been established. Even-type and odd-type aberrations are independently obtained from printed grating patterns on a wafer by three-beam interference under highly coherent illumination. Even-type aberrations, i.e., spherical aberration and astigmatism, are derived from the best focus positions of vertical, horizontal, and oblique grating patterns by an optical microscope. Odd-type aberrations, i.e., coma and three-foil, are obtained by detection of relative shifts of a fine grating pattern to a large pattern by an overlay inspection tool. Quantitative diagnosis of lens aberrations with a krypton fluoride (KrF) excimer laser scanner is demonstrated.

In optical lithography, it is a serious problem that aberrations in projection lenses reduce the imaging quality. Therefore techniques to measure the aberrations are required that will predict the adverse effects of aberrations on lithographic imagery and reduce them. We present a measurement method that uses a fine grating and its imaging condition to quantify coma, astigmatism, and spherical aberration. With this method, these aberrations can be described with simple expressions from the measured results. Application of this method revealed the coma of Zernike polynomials for our krypton fluoride (KrF) excimer-laser scanner.

In the present study, we evaluated the potential of bradykinin (BK) to induce the release of neutrophil and monocyte chemotactic activity (NCA and MCA) and cytokines from an alveolar type II epithelial cell line, A549 cells. BK stimulated A549 cells to release NCA and MCA in a dose- and time-dependent manner (P< 0.001). Checkerboard analysis revealed that both NCA and MCA involved chemotactic and chemokinetic activity. Molecular sieve column chromatography showed three molecular weight masses (near 19 kd, 8 kd, and 400 d) for NCA and several molecular weight peaks (near 66 kd, 25 kd, 19 kd, 16 kd, and 400 d) for MCA. The release of NCA and MCA was inhibited by cycloheximide and lipoxygenase inhibitors (P< 0.01). The NCA and MCA were inhibited by leukotriene B4 (LTB4) receptor antagonist (P< 0.01), and the concentration of LTB4 was high enough for NCA and MCA. Antibodies to interleukin (IL)-8 and granulocyte colony-stimulating factor (G-CSF) attenuated NCA (P< 0.01), and antibodies to monocyte chemotactic protein-1 (MCP-1), G-CSF, and transforming growth factor (TGF)-β attenuated MCA (P< 0.01). The levels of IL-8, G-CSF, MCP-1, and TGF-β increased time dependently (P< 0.01). BK also stimulated the release of ILeukin-6 from A549 cells (P< 0.001). The receptors responsible for the release of NCA, MCA, and individual chemokines involved both BKB1 and BKB2 receptors. These data suggest that BK may stimulate alveolar type II pneumocytes to release inflammatory cytokines, which then may modulate the lung inflammation.

We investigated a role of neuroregulation in the release of eosinophil chemotactic activity (ECA) from bovine bronchial epithelial cells (BBEC). BBEC were stimulated with acetylcholine (ACh) and substance P (SP), and the supernatant fluids were tested for ECA by a blind-well chemotactic chamber technique. BBEC released ECA in response to ACh and SP in a dose- and time-dependent manner. Checkerboard analysis showed that ECA in regard to ACh and SP was chemotactic rather than chemokinetic. Partial characterization revealed that ECA involved both lipids and peptides. The release of ECA in response to ACh and SP was inhibited by nonspecific and 5-specific lipoxygenase inhibitors and by cycloheximide (P< 0.01). Molecular-sieve column chromatography revealed that these mediators induced three molecular mass peaks (near 25 kDa, 9 kDa, and 400 Da, respectively). The lowest peak, which represented the predominant activity, was blocked by leukotriene B4-receptor antagonist (P< 0.01) but not by platelet-activating factor-receptor antagonist. The release of leukotriene B4in the supernatant fluids was increased in response to ACh and SP stimulation (P< 0.01). Platelet-activating factor was not detected. These results raise the possibility of a role of neuroregulation for the elaboration of ECA in the airway.

Motivational states consist of cognitive, emotional, and physiological components controlled by multiple brain regions. An integral component of this neural circuitry is the bed nucleus of the stria terminalis (BNST). Here, we identify that neurons within BNST that express the gene prepronociceptin(PnocBNST) modulate rapid changes in physiological arousal that occur upon exposure to motivationally salient stimuli. Using in vivotwo-photon calcium imaging, we find that PnocBNSTneuronal responses directly correspond with rapid increases in pupillary size when mice are exposed to aversive and rewarding odors. Furthermore, optogenetic activation of these neurons increases pupillary size and anxiety-like behaviors but does not induce approach, avoidance, or locomotion. These findings suggest that excitatory responses in PnocBNSTneurons encode rapid arousal responses that modulate anxiety states. Further histological, electrophysiological, and single-cell RNA sequencing data reveal that PnocBNSTneurons are composed of genetically and anatomically identifiable subpopulations that may differentially tune rapid arousal responses to motivational stimuli.

In the presence of potassium cyanide or the potassium cyanide/18-crown-6 complex as a cocatalyst, 1–2 mol% of titanium(salen) complex 1catalyses the asymmetric addition of achiral cyanoformates to aldehydes, giving cyanohydrin carbonates with high enantiomeric excesses; and catalyses the diastereoselective addition of chiral cyanoformates derived from α-methylbenzyl alcohol to aldehydes, a reaction which exhibits double asymmetric induction.

Performance of a Ru/Si multilayer polarizer of the double-crystal monochromator type is evaluated in the soft x-ray region. Its polarization was found to be higher than 99.5% at 89 and 97 eV.

Fiber optic sheets (10 lines/mm) have been made by a new technique in which a monomer is diffused into a ridged polymer film with a higher refractive index and then polymerized by gamma-ray irradiation. The diffusion profile was controllable from the clad type to the self-focusing type by adjusting the diffusion conditions. The attenuation in the polycarbonate light path (n = 1.59), enclosed with the chemically fixed methyl acrylate polymer (n = 1.49), was 0.5–0.7 dB/cm at λ = 633 nm.

The fluorescent emission spectra and fluorescent lifetimes have been measured for several available uranyl salts and natural mineral zippeite. The absolute quantum efficiency data of UO2SO4·0.5H2O, H2(UO2)2(PO4)2·8H2O, and UO2(CH3COO)2·2H2O have been obtained by the simultaneous measurement of the photoacoustic and excitation spectra.

We aim to measure the g-factor of a Λ in the nuclear medium. The g-factor can be measured from the probability of the Λ-spin-flip M1 transition. Using the Doppler shift attenuation method, we can measure it with 11ΛB hypernucleus. for this purpose, we have measured γ rays from 11ΛB and observed six γ transitions. Among them, the γ ray at 1482 keV is identified as E2(1/2+ →5/2+) transition.

Review: ca. 100 refs.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

We have evaluated the exposure latitude and the mask linearity of the lines and spaces (L/S), the isolated lines and the cell patterns used for DRAMs for various sizes down to 0.12 µ m. The exposure latitude was larger than 10% for all types of patterns with sizes larger than 0.12 µ m, using a mask of contrast of 3.7 in a mask-to-wafer gap of 20 µ m. We found that the mask linearity is insufficient and that mask pattern bias is required. The image shortening effect in the cell pattern was also evaluated. The results showed that the value of the shortening is higher when the design rule is smaller, the pattern density is sparser and the mask-to-wafer gap is larger. The value of the shortening in a 0.12-µ m- design- rule cell pattern was 13 nm, which is small enough to be corrected by simply giving a bias in the mask pattern.

In replicating line-and-space (L/S) patterns by X-ray proximity printing, optimizing the mask duty together with mask contrast is crucial to obtain high resolution in the 0.1 µ m region. We have successfully replicated L/Sdown to the pitch of 0.18 µ m, and evaluated the effects of mask L/Sratio. It was confirmed that the mask L/Sratio is transferred to the replicated pattern more faithfully as the proximity gap becomes narrower, and the ratio should be about 1:1 to achieve large exposure latitude together with wide dose margin. The results of our calculation agreed well with the experimental results upon introducing novel criteria to estimate replicated pattern width. Exposure latitude for 0.1±0.01 µ m L/Sreplication using the gaps of 10 and 15 µ m was within ±12% with feasible pattern profiles, although the specification of measured mask L/Sdiffered from the ideal one. Even for the gap of 20 µ m the exposure latitude remained within ±6%.

In lithography for LSI pattern exposure, pattern displacement was caused by aberrations of the projection lens. This displacement depended on the pattern position as well as the pattern size. Relative pattern shifts of the pattern to a 2.0 µm isolated pattern were measured using submicron bars-in-bars marks, which are similar to the overlay measurement marks. The measurement marks lie on the same mask and are exposed at the same time by a KrF excimer stepper with a numerical aperture (NA) of 0.6 and wavelength of 248 nm. The relative pattern shift showed that the lens had magnification errors which depended on the pattern size. Coma aberration was presumed from the measurement results of aerial image simulation. The coma was expressed in terms of Seidel aberrations. Wave aberration from the simulation corresponded with the measurement results for the two types of illuminations, i.e., such as a standard circuler source and an annular source.

Mask contrast optimization is essential for replicating sub-0.15-µ m patterns with relatively large mask-to-wafer gaps, e.g., larger than 20 µ m, which is strongly desired for industrial production. We have confirmed that decreasing the mask contrast to around 4 is very effective for increasing the exposure latitude for the grating patterns with pitch around 0.24 µ m, without deteriorating the exposure quality of larger patterns. The obtained exposure latitude for 0.12 µ m lines and spaces at the gap of 20 µ m was ±8.7% for ±10% replicated line-width change. How the mask pattern bias affects the replicated pattern was checked using the 0.24-µ m-pitch grating patterns. It was revealed that the dependence of the absorber width bias on the replicated pattern width is weaker than the linear correlation, as is suggested from the calculation of the Fresnel diffraction feature. It seems that when applying the larger mask-to-wafer gap to resolve a given pitch of grating patterns, the replicated pattern width becomes less sensitive to the line/space ratio on the mask.

An absorber profile is essential when replicating deep quarter-micron patterns because of the X-ray phase-shifting effect in the absorber. We have compared experimental results of 0.15 µm line-and-space (L/S) pattern with calculation based on Fresnel diffraction using the measured absorber profile and resist property. The experimental mask had a beveled absorber edge profile, and the 0.15 µm L/S exposure latitude values obtained with this mask are ±6% for a 30 µm gap, ±8% for 20 µm, and ±12% for 10 µm. The calculation showed good coincidence with respect to the dependence of the latitude on the gap, but the calculated pattern size is about 0.05 µm less than the experimental one. Simulation on the 0.1 µm L/S printability was further carried out for a 20 µm gap. Although the applied exposure dose was rather small, the pattern was resolved by the beveled-edge mask with a mask contrast of about 6.