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There is an increasing demand for high-performance computing on geophysical exploration applications, which implies more carbon emissions due to higher energy consumption. Furthermore, there is increasing concern about the environmental and social impact that this can generate. We show how cloud computing can handle these challenges simultaneously and thereby assist business leaders in their decision-making. Cloud computing is a paradigm in which users rent computing capacity from providers on a pay-as-you-go basis, thereby reducing the carbon footprint by up to 88%. It can run software for years uninterrupted using the same capital required to acquire and run on-premises infrastructure, even if such infrastructure has over a thousand graphics processing units. However, the managers must consider that challenges arise from using the cloud, such as trusting their data in a third-party server and expenses throughout the years, especially with storage.

Cloud computing is enabling users to instantiate and access high-performance computing clusters quickly. However, without proper knowledge of the type of application and the nature of the instances, it can become quite expensive. Our objective is to indicate that adequately choosing the instances provides a fast execution, which, in turn, leads to a low execution price, using the pay-as-you-go model on cloud computing. We have used graphics processing unit instances on the spot market to execute a seismic-data set interpolation job and compared their performance with regular on-demand central processing unit (CPU) instances. Furthermore, we explored how scaling could also improve the execution times at small price differences. The experiments have shown that, by using an instance with eight accelerators on the spot market, we obtain up to a 300 times speed-up compared with the on-demand CPU options, while being 100 times cheaper. Finally, our results have shown that seismic-imaging processing can be sped up by an order of magnitude with a low budget, resulting in faster and cheaper processing turnaround time and enabling new possible imaging techniques.

The usage of graphics processing units is already known as an alternative to traditional multi-core CPU processing, offering faster performance in the order of dozens of times in parallel tasks. Another new computing paradigm is cloud computing usage as a replacement to traditional in-house clusters, enabling seemingly unlimited computation power, no maintenance costs, and cutting-edge technology, dynamically on user demand. Previously those two tools were used to accelerate the estimation of Common Reflection Surface (CRS) traveltime parameters, both in zero-offset and finite-offset domain, delivering very satisfactory results with large time savings from GPU devices alongside cost savings on the cloud. This work extends those results by using GPUs on the cloud to accelerate the Offset Continuation Trajectory (OCT) traveltime parameter estimation. The results have shown that the time and cost savings from GPU devices’ usage are even larger than those seen in the CRS results, being up to fifty times faster and sixty times cheaper. This analysis reaffirms that it is possible to save both time and money when using GPU devices on the cloud and concludes that the larger the data sets are and the more computationally intensive the traveltime operators are, we can see larger improvements. Keywords: cloud computing, GPU, seismic processing. Estendendo o uso de placas graficas na nuvem para economias em regularizacao de dados sismicos RESUMO. O uso de aceleradores graficos para processamento ja e uma alternativa conhecida ao uso de CPUs multi-cores, oferecendo um desempenho na ordem de dezenas de vezes mais rapido em tarefas paralelas. Outro novo paradigma de computacao e o uso da nuvem computacional como substituta para os tradicionais clusters internos, possibilitando o uso de um poder computacional aparentemente infinito sem custo de manutencao e com tecnologia de ponta, dinamicamente sob demanda de usuario. Anteriormente essas duas ferramentas foram utilizadas para acelerar a estimacao de parâmetros do tempo de trânsito de Common Reflection Surface (CRS), tanto em zero-offset quanto em offsets finitos, obtendo resultados satisfatorios com amplas economias tanto de tempo quanto de dinheiro na nuvem. Este trabalho estende os resultados obtidos anteriormente, desta vez utilizando GPUs na nuvem para acelerar a estimacao de parâmetros do tempo de trânsito em Offset Continuation Trajectory (OCT). Os resultados obtidos mostraram que as economias de tempo e dinheiro foram ainda maiores do que aquelas obtidas no CRS, sendo ate cinquenta vezes mais rapido e sessenta vezes mais barato. Esta analise reafirma que e possivel economizar tanto tempo quanto dinheiro usando GPUs na nuvem, e conclui que quanto maior for o dado e quanto mais computacionalmente intenso for o operador, maiores serao os ganhos de desempenho observados e economias. Palavras-chave: computacao em nuvem, GPU, processamento sismico.

We present studies on the low-energy magnetic excitations in the Lieb-Mattis (LM) ferrimagnetic phase. We investigate the low-energy magnetic excitations in the mixed spin-($\frac{1}{2},\frac{5}{2}$) chain $(4\ensuremath{-}\mathrm{Br}\ensuremath{-}o\ensuremath{-}\mathrm{Me}\mathrm{Py}\ensuremath{-}\mathrm{V})\mathrm{Fe}{\mathrm{Cl}}_{4}$ based on low-temperature specific heat and multifrequency electron spin resonance (ESR) measurements. A clear $\sqrt{T}$ term is observed in the specific heat, which indicates a contribution of the low-energy magnetic excitation with a ferromagnetic quadratic dispersion expected in the LM ferrimagnetic state. Through the ESR mode analysis, we examine the effects of magnetic anisotropy on the excited states in the LM plateau phase.

Topological properties in material science have recently received tremendous attention, as exemplified by topological insulators. As for quantum spin systems, the Haldane chain with integer spins is the best known example1. The realization of a topological quantum phase in the Haldane chain is an innovative research development related to the 2016 Nobel Prize in Physics. For mixed spin chains composed of two different spins, the appearance of a topologically quantized magnetization plateau is predicted by the Lieb-Mattis theorem2 in combination with the Oshikawa-Yamanaka-Affleck criterion3. However, the actual magnetization plateau in the mixed spin chain has not yet been observed. Here, we present a model compound forming a mixed spin-(1/2, 5/2) chain. We observe a clear Lieb-Mattis plateau and well explain it quantitatively. The present results demonstrate a quantum many-body effect based on quantum topology and provide a new stage in the search for topological properties in condensed matter physics.

Summary Many seismic programs are possible due to the existence of adjoint state methods, e.g., Reverse Time Migration (RTM), which offers reliable subsurface imaging with the drawback of a naive implementation that requires a high memory consumption. The ability to recompute state from saved boundaries and the improved memory usage of checkpointing are attractive because they bring better alternatives to the naive approach. However, while the former still poses a considerable memory usage under large datasets, the latter presents a very high recomputation demand. To leverage the attractive properties of both strategies, we propose a hybrid approach that uses checkpointing for recovering snapshot borders that later are used by boundary saving to reconstruct the wavefield during the backpropagation. Numerical results demonstrate the quality of our implementation, and comparative values indicate gains from two to three times less memory usage when compared with the simple boundary saving. At the same time, the recomputation overhead is kept low. Therefore, the strategy presents itself as an excellent alternative to the existing methods, mainly when non-attenuative mediums are considered.

Este trabalho tem como objetivo investigar o desempenho do traçamento de raios empregado no imageamento sísmico utilizando a nuvem computacional, visando maximizar a escalabilidade do mesmo e minimizar o tempo de execução. Os resultados obtidos mostram que (i) balancear a carga de trabalho alterando a quantidade de raios traçados por nó apresenta redução nos tempos de execução e (ii) a escalabilidade depende da quantidade total de raios.

Summary The cloud computing paradigm is enabling the execution of high performance computing software and is a potential alternative to traditional clusters. Not only that, but public providers, such as Microsoft and Amazon, offer a wide variety of virtual machine specifications and prices. Correctly choosing the proper hardware specification for the software can reduce execution times and money. In light of this, we developed an algorithm that automatically selects the virtual machine configurations with the best cost per performance ratio in the Amazon Web Service cloud platform for a running software, using its performance in differently priced configurations as input to the selection. Our results showed that the algorithm is capable of selecting the instances that offers the best cost per performance within minutes, approaching the optimal cost as the dataset size increases.

Laser and stretching are used to treat skeletal muscle injuries. This study aimed to evaluate the effects of GaAs laser and stretching in the morphology of the tibialis anterior (TA) muscle after contusion. Thirty-six male rats (349±23g) were divided into six groups (n=6): control group (CG); lesion group (LG); lesion and laser group (LLG); lesion and stretching group (LSG); lesion, laser and stretching group (LLSG); and stretching group (SG). TA was wounded by a contusion apparatus. We used GaAs laser 4.5 J/cm2 dose for 32 s each, beginning 48 h after lesion, for 7 days, once a day. Manual passive stretching was applied by 10 repetitions for 1 minute, initiating on the 8th day, once a day, 3 times a week, during 3 weeks. After 4 weeks, rats were euthanized and we analyzed: muscle weight and length, cross sectional area of muscle fibers (CSAMF), serial sarcomere number (SSN), sarcomere length, and percentage of connective tissue. Comparisons among groups were made by ANOVA and post hoc Tukey tests, with the significance level set at ≤ 0.05. The serial sarcomere number of LLSG was higher than LSG. The sarcomere length of LSG was superior to LLG, LLSG, and SG. SG increased SSN compared to CG, while the percentage of connective tissue of SG decreased in comparison to LLSG. Thus, the sarcomerogenesis of injured muscles was enhanced by laser therapy, stretching, and association of both. The stretching protocol was enough to increase SSN of intact muscles.

Cloud computing platforms offer a wide variety of computational resources with different performance specifications for different prices. In this work, we experiment how Spot instances and Availability Zones on the Amazon Web Services (AWS) could be utilized to reduce the processing cost. Not only that, but we propose an instance management algorithm in AWS to minimize the execution cost of programs implemented using the programming model Scalable Partially Idempotent Task System (SPITS). Our results show that the proposed method is able to identify and dynamically adjust the virtual machine types that offer the best cost per performance ratio.

Summary Public cloud providers, such as the Microsoft Azure and the Amazon Web Services (AWS), offer a wide variety of virtual machines, with different specifications, and prices, that are enabling users to run high-performance programs without buying specialized and expensive hardware. Moreover, some providers, such as AWS, allow the user to bid for lower cost virtual machines, called Spot Instances. Nonetheless, these machines may be terminated within a few minutes of warning at the provider discretion. In this work, we leveraged the SPITS programming model to implement a high-performance and fault-tolerant seismic processing application that is proper for execution on Spot instances and analyzed how different virtual machines from the AWS may affect the performance and the price of the computation. Our experimental results indicate that Spot instances have similar performance to regular instances but are roughly three times less expensive. Finally, we show that AWS groups virtual machines in Availability Zones and that selecting virtual machines from different zones may also affect the total execution cost.

O objetivo deste trabalho é a investigação do uso da nuvem computacional para a execução de algoritmos no processamento sísmico, visando minimizar o custo financeiro com o uso do serviçoo em nuvem contra a compra de máquinas físicas. Os resultados obtidos indicam que (i) as máquinas virtuais equipadas com GPU apresentam o menor custo/benefício para a aplicação executada, (ii) existe escalabilidade no desempenho e esta pode ser explorada para obter tempos de execuções menores e, por fim, (iii) o uso da nuvem permite que não seja necessária a compra de novas máquinas físicas.

Molecular Dynamics (MD) simulations were conducted to investigate the influence of applied tensile strain on defect production during cascade damages at various Primary Knock-on Atom (PKA) energies of 1–30 keV. When 1% strain was applied, the number of surviving defects increased at PKA energies higher than 5 keV, although they did not increase at 1 keV. The rate of increase by strain application was higher with higher PKA energy, and attained the maximum at 20 keV PKA energy with a subsequent gradual decrease at 30 keV PKA energy The cluster size, mostly affected by strain, was larger with higher PKA energy, although clusters with fewer than seven interstitials did not increase in number at any PKA energy.

Objectives: The present study evaluated the prognostic implications of insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor (HER)-2 in patients with colorectal cancer (CRC). Methods: Our subjects were 91 patients who underwent surgery and subsequently received fluoropyrimidines. Expressions of IGF-1R, EGFR and HER-2 in primary lesions were analyzed immunohistochemically to determine the prognostic significance of these biomarkers. Results: Overexpression was found for IGF-1R in 48 tumors (53%), EGFR in 57 (63%) and HER-2 in 2 (2%). Overexpression of IGF-1R was significantly correlated with shorter survival from the start of first-line chemotherapy (p = 0.033). Overexpression of EGFR was a significant predictor of clinical response to fluoropyrimidines (p = 0.032). Multivariate analysis of potential prognostic factors showed that IGF-1R expression and worsened performance status were independent predictors of poor outcomes. Conclusions: Our results suggest that anti-IGF-1R strategies may offer a useful approach in molecular therapy for CRC, which has the potential to improve outcomes.

To address the shortage of research-trained pharmaceutical scientists (or doctor of pharmacy [Pharm.D.] scientists), a 2-day pharmacy research conference titled "Pharm.D. Pathways to Biomedical Research" was convened on December 13-14, 2006, at the National Institutes of Health (NIH) campus (Bethesda, MD). The workshop included invited speakers and participants from academia, industry, and government. Forty-two pharmacy schools were represented, including deans and clinical pharmaceutical scientists with current NIH funding. In addition, several pharmacy professional organizations were represented--American Association of Colleges of Pharmacy, American College of Clinical Pharmacy, American Society of Health-System Pharmacists, and the Accreditation Council on Pharmaceutical Education. The workshop was divided into three sessions followed by breakout discussion groups: the first session focused on presentations by leading pharmaceutical scientists who described their path to success; the second session examined the NIH grant system, particularly as it relates to training opportunities in biomedical research and funding mechanisms; and the third session addressed biomedical research education and training from the perspective of scientific societies and academia. We summarize the discussions and findings from the workshop and highlight some important considerations for the future of research in the pharmacy community. This report also puts forth recommendations for educating future pharmaceutical scientists.

Ar+ ion bombardment of carbon surfaces (both bulk carbon and carbon-coated substrates) induced the growth of conical protrusions, and either aligned or nonaligned carbon nanofibers (CNFs) grew on the tips without any catalyst even at room temperature. CNFs thus grown were 20 ~ 50 nm in diameter and 0.2~10 mum in length. Very interestingly, no CNF grew without cone bases, and more than one CNF never grew on the respective cone tips. The solely standing and densely distributed CNFs were successfully applied to CNF-based scanning probe microscope (SPM) tips and field electron emission (FEE) sources, respectively. Since the myriad applications are possible, sputter-induced CNFs are believed to be quite promising as one-dimensional nanomaterials

For the direct fabrication of densely distributed one dimensional nanostructures on Si substrates, Si (1 0 0) surfaces were bombarded by obliquely incident 3 keV Ar + ions with a simultaneous supply of Mo seed atoms at various temperatures ranging from room temperature to 400 °C. The surface sputtered at room-temperature with Mo seeding was characterized by the nanocones pointing in the direction of the incident ion beam. In addition, they possessed a so-called “web” at their acute-angle side. This web decreased in size with an increase in the sputtering temperature. Thus, the projections fabricated at elevated temperatures were featured by the nanorod-like structure rather than conical structure. With increasing the sputtering temperature, projections decreased in base diameter (from ∼90 nm at 200 °C to ∼50 nm at 400 °C) while they increased in both length (from ∼160 nm at 200 °C to ∼240 nm at 400 °C) and numerical density (from ∼5 × 10 7 mm −2 at 200 °C to ∼1.2 × 10 8 mm −2 at 400 °C). The controlled fabrication of such densely distributed one dimensional nanoprojections on Si using ion beam technique, we believe, would open up a variety of applications such as nanoelectronics and optoelectronics devices.

A very simple method to synthesize densely distributed carbon nanofibers (CNFs) on flexible plastic substrates at room temperature with no catalyst is demonstrated. Carbon film was deposited onto polyimide, poly-ethylene-terephthalate (PET) films, Si plates and a Ni mesh, which were then sputtered with obliquely incident Ar + ions at 3 keV at room temperature. Linear-shaped CNFs oriented in the incidence direction of the ion beam grew on the sputtered substrates, as confirmed by scanning (SEM) and transmission electron microscopes (TEM). CNF growth on a PET substrate, which is a non-heat-tolerant plastic, has never been reported so far. CNFs thus grown were characterized as amorphous without a hollow structure. The diameter of CNFs was almost identical (20–30 nm) despite a large difference in CNF length (0.1–4 μm). In addition, the CNF-tipped cones were demonstrated to act successfully as a template to fabricate one dimensional (1-D) zinc oxide (ZnO) nanostructures on a PET substrate. Thus, it was believed that the ion-irradiation technique would open up a new approach to fabricate any kinds of 1-D nanomaterials on flexible substrates at room temperature.

A novel method for the direct growth of a single carbon nanofiber (CNF) onto the tip of a commercially available scanning probe microscope (SPM) using Ar+-ion irradiation was demonstrated. This method was proposed on the basis of the experimental fact that the Ar+ ion bombardment of carbon coated substrates induced the formation of conical protrusions that possessed a single CNF at their tip. Commercially available Si SPM tips were coated with carbon and then were Ar+-ion bombarded at room temperature and at 200 °C. On the ion-bombarded SPM tips, single CNFs of about 30 nm in diameter grew. Their length, which was controlled by varying the sputtering duration, was typically 0.5–1.5 µm. Using the CNF-tipped probes thus prepared, clear atomic force microscope (AFM) images with a high spatial resolution were attained for Si-grating samples. No deterioration in the spatial resolution was detected after repeated scans for 90 min. Thus, the ion-irradiation method was concluded to be quite promising for the fabrication of practical CNF-tipped SPM probes.

Glassy carbon plates, a Ni mesh coated with a carbon film and mechanically polished graphite plates were Ar+ ion-bombarded with and without a simultaneous Mo supply at room temperature. Conical protrusions were formed on the sputtered surfaces, and in some cases carbon nanofibers (CNFs) 0.2–10 μm in length and 10–50 nm in diameter grew on the tips. The growth of CNF-tipped-cones was optimized in terms of the ion-incidence angle and the rate-ratio of sputtering and seeding. Oblique sputtering was proved to be quite effective to grow the CNF-tipped-cones. Thus, the redeposited massive carbon atoms onto cones were thought to diffuse toward the cone tips, resulting in CNF formation. This growth mechanism was confirmed by transmission electron microscope (TEM) observation disclosing the boundary-less structure between conical bases and CNFs. TEM observation of CNF-tipped-cones also revealed no-hollow structure and an amorphous nature of CNFs. Since this sputtering method is a room-temperature process and quite straightforward, ion-induced CNFs promise to have myriad applications, such as field emission sources for flat panel displays.

The electron field emission from zinc oxide (ZnO) nanoneedles on flexible plastic substrates is reported. ZnO thin films were first deposited on plastic substrates at 200 °C using a filtered cathodic vacuum arc technique; the films were then bombarded by Ar+ ion. After ion beam irradiation, high-density ZnO nanoneedle arrays were selectively formed on the thin films. The average diameter and length of the ZnO nanoneedles is around 100 and 700 nm respectively. Field emission measurement showed a fairly low threshold voltage of 4.1 V µm−1 with a current density of 1 µA cm−2. The emission current density can be as high as 1 mA cm−2 at 9.6 V µm−1. The result establishes a method of fabricating a flexible field emitter, which should find practical applications in vacuum electronic devices.

Phthalates have been shown to elicit contrasting effects on the testis and the liver, causing testicular degeneration and promoting abnormal hepatocyte proliferation and carcinogenesis. In the present study, we compared the effects of phthalates on testicular and liver cells to better understand the mechanisms by which phthalates cause testicular degeneration. In vivo treatment of rats with di-(2-ethylhexyl) phthalate (DEHP) caused a threefold increase of germ cell apoptosis in the testis, whereas apoptosis was not changed significantly in livers from the same animals. Western blot analyses revealed that peroxisome proliferator-activated receptor (PPAR) alpha is equally abundant in the liver and the testis, whereas PPAR gamma and retinoic acid receptor (RAR) alpha are expressed more in the testis. To determine whether the principal metabolite of DEHP, mono-(2-ethylhexyl) phthalate (MEHP), or a strong peroxisome proliferator, 4-chloro-6(2,3-xylindino)-2-pyrimidinylthioacetic acid (Wy-14,643), have a differential effect in Sertoli and liver cells by altering the function of RAR alpha and PPARs, their nuclear trafficking patterns were compared in Sertoli and liver cells after treatment. Both MEHP and Wy-14,643 increased the nuclear localization of PPAR alpha and PPAR gamma in Sertoli cells, but they decreased the nuclear localization of RAR alpha, as previously shown. Both PPAR alpha and PPAR gamma were in the nucleus and cytoplasm of liver cells, but RAR alpha was predominant in the cytoplasm, regardless of the treatment. At the molecular level, MEHP and Wy-14,643 reduced the amount of phosphorylated mitogen-activated protein kinase (activated MAPK) in Sertoli cells. In comparison, both MEHP and Wy-14,643 increased phosphorylated MAPK in liver cells. These results suggest that phthalates may cause contrasting effects on the testis and the liver by differential activation of the MAPK pathway, RAR alpha, PPAR alpha, and PPAR gamma in these organs.

We have constructed a microprotrusion fabrication system consisting of a differentially pumped ion gun and a seed material supply source, both of which operate under an UHV condition. Using this system, Si (1 0 0) surfaces were bombarded by obliquely incident 3 keV Ar + ions at room temperature with and without a simultaneous supply of Mo atoms. The sputtered surfaces without a Mo supply were flat or characterized by a nano-sized rippled structure, whereas those with simultaneous Mo seeding displayed densely distributed Mo-seeded cones. For a very low seeding rate of ∼7.2 × 10 −2 nm/min, the optimum sputtering rate needed to induce seed cone growth over a sputtered crater was determined to be 4.4 nm/min. The size and number density of cones thus grown at the crater center were estimated to be 65–230 nm in width and ∼3 × 10 7 mm −2 , respectively. The controlled fabrication of such seed cones may be applicable to the development of electron sources whose basic operational mechanism is field-electron emission.

Background: Few studies have examined tumor cell distribution following laparoscopic surgery for colorectal cancer. We examined the effect of carbon dioxide pneumoperitoneum on the distribution of intrasplenically injected colon cancer cells in mice. Methods: Mice were intrasplenically injected with 2 × 104 colon 26 cells labeled with 111In-oxine and were randomized to undergo pneumoperitoneum at 10 mmHg for 30 min or to receive no treatment other than anesthesia. Radioactivity of the liver, lungs, and spleen was measured 30, 60, 90, or 150 min following tumor inoculation. Results: The dynamic changes in the hepatic radioactivity were not similar between groups. However, the values were not significantly different at any time point. The radioactivity of lungs was extremely low in both groups throughout the experimental period. Conclusions: Pneumoperitoneum does not appear to cause the accumulation of intraportally spreading tumor cells in the liver, but it may affect the dynamic changes of tumor cells. Also, tumor cell localization in the lungs is negligible in both pneumopentoneum and control groups.

We characterize a novel microsome system that forms high-molecular-mass (HMM) CYP3A, CYP2E1, and ubiquitin conjugates, but does not alter CYP4A or most other microsomal proteins. The formation of the HMM bands was observed in hepatic microsomes isolated from rats treated 1 week or more with high doses (50 mg/kg/day) of nicardipine, clotrimazole, or pregnenolone 16alpha-carbonitrile, but not microsomes from control, dexamethasone-, nifedipine-, or diltiazem-treated rats. Extensive washing of the microsomes to remove loosely attached proteins or cytosolic contaminants did not prevent the conjugation reaction. In contrast to prototypical ubiquitination pathways, this reaction did not require addition of ubiquitin, ATP, Mg(2+), or cytosol. Addition of cytosol did result in the degradation of the HMM CYP3A bands in a process that was not blocked by proteasome inhibitors. Immunoprecipitated CYP3A contained HMM ubiquitin. Even so, mass spectrometric analysis of tryptic peptides indicated that the HMM CYP3A was in molar excess to ubiquitin, suggesting that the formation of the HMM CYP3A may have resulted from conjugation to itself or a diffuse pool of ubiquitinated proteins already present in the microsomes. Addition of CYP3A substrates inhibited the formation of the HMM CYP3A and the cytosol-dependent degradation of HMM CYP3A. These results suggest that after extended periods of elevated CYP3A expression, microsomal factors are induced that catalyze the formation of HMM CYP3A conjugates that contain ubiquitin. This conjugation reaction, however, seems to be distinct from the classical ubiquitination pathway but may be related to the substrate-dependent stabilization of CYP3A observed in vivo.

We are conducting experiments to generate self-amplified spontaneous emission (SASE) in the far-infrared region and to measure its characteristics, using a single bunch electron beam accelerated with the L-band linac at ISIR, Osaka University. We have measured the wavelength spectra of SASE in the wavelength region between 80 and 180 μm using a grating monochromator and a Ge : Ga detector. The measured spectral widths of the fundamental peak are slightly larger than those predicted by the one-dimensional model. We have also observed the second harmonic peak of SASE.

We are conducting experiments of self-amplified spontaneous emission (SASE) in the far-infrared region at ISIR, Osaka University by using a high brightness single-bunch beam from the L-band linac. As the first step, characteristics of the SASE-FEL are estimated using the one-dimensional analytic formulas and the measured characteristics of the electron beam. The calculated FEL parameter is 0.02 and the gain length is 0.14 m at an electron energy of 13 MeV and K =1.472. Recently, we observed a strong optical signal radiated from a single-bunch beam passing through the wiggler for the existing infrared FEL system.

We are conducting FEL experiments using the infrared FEL system based on the L-band electron linac at ISIR, Osaka University, to extend the wavelength region toward the longer-wavelength side and to study FEL dynamics in the long wavelength region. The FEL wavelength was extended to 150 μm, which is the longest wavelength so far obtained with FELs based on RF linacs. We observed a phenomenon that FEL oscillation was obtained at two different optical cavity lengths but not in between them.

Pretreatment of male B6C3F1 mice with clofibric acid (CFA) or trichloroacetic acid (TCA) in the drinking water results in a marked decrease in the lipoperoxidative response as measured by the production of thiobarbituric acid reactive substances (TBARS) in mouse liver homogenates following acute dosing with TCA or dichloroacetic acid (DCA). Pretreatment with TCA or CFA also increased palmitoyl-CoA oxidase activity, microsomal 12-(ω) hydroxylation of lauric acid and expression of P450 4A isoforms. At the doses utilized, DCA-pretreatment did not increase the level of P450 4A protein, or markers of peroxisome proliferation. However, DCA-pretreatment did result in enhanced levels of TBARS, following acute dosing with DCA, compared to controls. Pretreatment with DCA, TCA, or CFA did not alter p-nitrophenol hydroxylation (an assay specific for P450 2E1), and no increases in immunodetectable P450 2E1, 4A, 1A1/2, 2B1/2 or 3A1 protein were observed. Assays from CFA- and TCA-pretreated mice suggest that the reduction in the TBARS response seen in TCA-pretreated animals results from activities associated with peroxisome proliferation. This might result from the induction of systems efficient in scavenging of peroxide intermediates or detoxification of aldehyde by-products of lipid peroxidation.

An acetylene moiety was introduced to a carbonyl carbon of amide group via its triflate in the presence of palladium catalyst. The reaction proceeded smoothly under mild conditions. Utilizing this methodology, a model compound of dynemicin A bearing acetylene group was synthesized.

During the period from 25 May 1991 to 30 May 1992 the atmospheric concentrations and depositions of oxides of sulfur were continuously measured in a suburban masson pine forest which is currently experiencing severe dieback, in Chongqing, China. The annual mean concentrations of SO 2 and particulate SO 4 2- were 220 μ g/m 3 (77 ppbv) and 32 μ g/m 3 respectively. The atmospheric concentrations of these sulfur compounds were high in late autumn and winter. The annual wet and dry depositions of sulfur to the forest as measured by throughfall and stemflow were 93.1 and 46.6 kgSha -1 a -1 respectively. These depositions are among the highest level ever reported in the world. Althogh the cause of the dieback of the masson pine trees has not been unequivocally determined, it is probable that the direct impact of SO 2 is more likely the cause than acid deposition.