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Much effort has been employed to improve the quality of embryos obtained by in vitro production (IVP) given the relevance of this technology to current livestock systems. In this context, dynamic IVP systems have proved beneficial to the embryo once they mimic fluid flows and mechanical forces resulting from the movement of ciliated cells and muscle contraction in the reproductive tract. In the present study, we sought to confirm these initial findings as well as assess potential molecular consequences to the embryo by applying micro-vibration (45 Hz for 5 s once per 60 min) during both oocyte maturation and embryo culture in cattle. As a result, micro-vibration led to lower incidence of apoptosis in blastocysts following vitrification-thawing. Further analyses revealed epigenetic and transcriptional changes in blastocysts derived from the micro-vibration treatment, with a total of 502 differentially expressed genes. Enrichment analyses linked differentially expressed genes to 'Oxidative phosphorylation', 'Cytokine-cytokine receptor interaction', and 'Signaling pathways regulating pluripotency of stem cells'. Yet, a meta-analysis indicated that the transcriptional changes induced by micro-vibration were not toward that of in vivo-derived embryos. In conclusion, micro-vibration increases the cryoresistance of bovine embryos, but caution should be taken given the unclear consequences of epigenetic and transcriptional abnormalities induced by the treatment.

The microbiological assay of total cobalamin (vitamin B

Cu-containing nitrite reductases that convert NO2 - to NO are critical enzymes in nitrogen-based energy metabolism. Among organisms in the order Rhizobiales, we have identified two copies of nirK, one encoding a new class of 4-domain CuNiR that has both cytochrome and cupredoxin domains fused at the N terminus and the other, a classical 2-domain CuNiR (Br2D NiR). We report the first enzymatic studies of a novel 4-domain CuNiR from Bradyrhizobium sp. ORS 375 (BrNiR), its genetically engineered 3- and 2-domain variants, and Br2D NiR revealing up to ~ 500-fold difference in catalytic efficiency in comparison with classical 2-domain CuNiRs. Contrary to the expectation that tethering would enhance electron delivery by restricting the conformational search by having a self-contained donor-acceptor system, we demonstrate that 4-domain BrNiR utilizes N-terminal tethering for downregulating enzymatic activity instead. Both Br2D NiR and an engineered 2-domain variant of BrNiR (Δ(Cytc-Cup) BrNiR) have 3 to 5% NiR activity compared to the well-characterized 2-domain CuNiRs from Alcaligenes xylosoxidans (AxNiR) and Achromobacter cycloclastes (AcNiR). Structural comparison of Δ(Cytc-Cup) BrNiR and Br2D NiR with classical 2-domain AxNiR and AcNiR reveals structural differences of the proton transfer pathway that could be responsible for the lowering of activity. Our study provides insights into unique structural and functional characteristics of naturally occurring 4-domain CuNiR and its engineered 3- and 2-domain variants. The reverse protein engineering approach utilized here has shed light onto the broader question of the evolution of transient encounter complexes and tethered electron transfer complexes. ENZYME: Copper-containing nitrite reductase (CuNiR) (EC 1.7.2.1). DATABASE: The atomic coordinate and structure factor of Δ(Cytc-Cup) BrNiR and Br2D NiR have been deposited in the Protein Data Bank (http://www.rcsb.org/) under the accession code 6THE and 6THF, respectively.

Made available in DSpace on 2018-12-11T17:04:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-10-01 The translation elongation factor eIF5A is conserved through evolution and is necessary to rescue the ribosome during translation elongation of polyproline-containing proteins. Although the site of eIF5A binding to the ribosome is known, no systematic analysis has been performed so far to determine the important residues on the surface of eIF5A required for ribosome binding. In this study, we used clustered charged-to-alanine mutagenesis and structural modeling to address this question. We generated four new mutants of yeast eIF5A: tif51A-4, tif51A-6, tif51A-7 and tif51A-11, and complementation analysis revealed that tif51A-4 and tif51A-7 could not sustain cell growth in a strain lacking wild-type eIF5A. Moreover, the allele tif51A-4 also displayed negative dominance over wild-type eIF5A. Both in vivo GST-pulldowns and in vitro fluorescence anisotropy demonstrated that eIF5A from mutant tif51A-7 exhibited an importantly reduced affinity for the ribosome, implicating the charged residues in cluster 7 as determinant features on the eIF5A surface for contacting the ribosome. Notably, modified eIF5A from mutant tif51A-4, despite exhibiting the most severe growth phenotype, did not abolish ribosome interactions as with mutant tif51A-7. Taking into account the modeling eIF5A + 80S + P-tRNA complex, our data suggest that interactions of eIF5A with ribosomal protein L1 are more important to stabilize the interaction with the ribosome as a whole than the contacts with P-tRNA. Finally, the ability of eIF5A from tif51A-4 to bind to the ribosome while potentially blocking physical interaction with P-tRNA could explain its dominant negative phenotype. Department of Biological Sciences School of Pharmaceutical Sciences São Paulo State University-UNESP, Rod Araraquara-Jaú Km01 Physics and Interdisciplinary Science Department Physics Institute of Sao Carlos University of Sao Paulo-USP Molecular and Cellular Biology Department University of California Department of Biological Sciences School of Pharmaceutical Sciences São Paulo State University-UNESP, Rod Araraquara-Jaú Km01

Fertility associated with age has been poorly documented in cattle. There is evidence that more than 50% of cows became infertile (failure to bear a calf for two successive years) at the age of 15. The causes of infertility in cows have been attributed to poor oocyte quality and/or follicle depletion. The present study aimed to compare the rates of oocyte and invitro embryo production of fertile cows older than 15 years. Sixteen Nellore cows (Bos taurus indicus) 200.3±4.9 months old were submitted to two ovum pickup series (OPU1 and OPU2) at a 2-year (2017 and 2019) interval. Before the OPU1 of each series, the cows were prepared with an IM injection of 2mg estradiol benzoate and 0.15mg prostaglandin F2α analogue and a progesterone-releasing intravaginal device (1g). After five days, the progesterone-releasing intravaginal device was withdrawn and the OPU1 was performed. The second OPU (OPU2) was performed 5 days later to aspirate only the growing follicles. The number and morphologic quality of recovered cumulus-oocyte complexes were registered. After IVM (tissue culture medium 199) and fertilization (Tyrode's solution) of cumulus-oocyte complexes, the presumptive zygotes were cultured in synthetic oviductal fluid with amino acids to assess developmental rates to blastocyst. Data were analysed by chi-squared and Wilcoxon test. The number of oocytes recovered at OPU1 was higher in 2107 than in 2019 (27.8±6.6 vs. 10.8±4.2; P

Made available in DSpace on 2018-12-11T17:23:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-11-22 Among the biologically active triterpenes, friedelin has the most-rearranged structure produced by the oxidosqualene cyclases and is the only one containing a cetonic group. In this study, we cloned and functionally characterized friedelin synthase and one cycloartenol synthase from Maytenus ilicifolia (Celastraceae). The complete coding sequences of these 2 genes were cloned from leaf mRNA, and their functions were characterized by heterologous expression in yeast. The cycloartenol synthase sequence is very similar to other known OSCs of this type (approximately 80% identity), although the M. ilicifolia friedelin synthase amino acid sequence is more related to β-amyrin synthases (65-74% identity), which is similar to the friedelin synthase cloned from Kalanchoe daigremontiana. Multiple sequence alignments demonstrated the presence of a leucine residue two positions upstream of the friedelin synthase Asp-Cys-Thr-Ala-Glu (DCTAE) active site motif, while the vast majority of OSCs identified so far have a valine or isoleucine residue at the same position. The substitution of the leucine residue with valine, threonine or isoleucine in M. ilicifolia friedelin synthase interfered with substrate recognition and lead to the production of different pentacyclic triterpenes. Hence, our data indicate a key role for the leucine residue in the structure and function of this oxidosqualene cyclase. Instituto de Química Univ. Estadual Paulista UNESP, Rua Prof. Francisco Degni 55 Centro de Pesquisa e Inovaçaõ em Biodiversidade e Fármacos Instituto de Física de Saõ Carlos Universidade de Saõ Paulo Faculdade de Ciências Farmaceûticas Univ. Estadual Paulista-UNESP, Rod. Araraquara-Jaú km 1 Faculdade de Ciências Farmaceûticas Universidade de Saõ Paulo, Avenida do Café s/n Instituto de Química Univ. Estadual Paulista UNESP, Rua Prof. Francisco Degni 55 Faculdade de Ciências Farmaceûticas Univ. Estadual Paulista-UNESP, Rod. Araraquara-Jaú km 1

Stress is a key indicator of wellness in human beings and a prime contributor to performance degradation and errors during various human tasks. The overriding purpose of this paper is to propose two algorithms (probabilistic and non-probabilistic) that iteratively track stress states to compute a wellness index in terms of the stress levels. This paper adopts the physiological view-point that high stress is accompanied with large deviations in biometrics such as body temperature, heart rate, etc., and the proposed algorithms iteratively track these fluctuations to compute a personalized wellness index that is correlated to the engagement levels of the tasks performed by the user. In essence, this paper presents a quantitative relationship between temperature, occupational stress, and wellness during different tasks. The simplicity of the statistical inference algorithms make them favorable candidates for implementation on mobile platforms such as smart phones in the future, thereby providing users an inexpensive application for self-wellness monitoring for a healthier lifestyle.

eIF5A is highly conserved from archaea to mammals, essential for cell viability and the only protein known to contain the essential amino acid residue hypusine, generated by a unique posttranslational modification. eIF5A was originally identified as a translation initiation factor due to its ability to stimulate the formation of the first peptide bond. However, recent studies have shown that depletion of eIF5A causes a significant decrease in polysome run-off and an increase in the ribosome transit time, suggesting that eIF5A is actually involved in the elongation step of protein synthesis. We have previously shown that the depletion mutant tif51A-3 (eIF5A(C39Y/G118D)) shows a sicker phenotype when combined with the dominant negative mutant eft2 ( H699K ) of the elongation factor eEF2. In this study, we used the eIF5A(K56A) mutant to further investigate the relationship between eIF5A and eEF2. The eIF5A(K56A) mutant is temperature sensitive and has a defect in protein synthesis, but instead of causing depletion of the eIF5A protein, this mutant has a defect in hypusine modification. Like the mutant tif51A-3, the eIF5A(K56A) mutant is synthetic sick with the mutant eft2 ( H699K ) of eEF2. High-copy eEF2 not only improves cell growth of the eIF5A(K56A) mutant, but also corrects its increased cell size defect. Moreover, eEF2 suppression of the eIF5A(K56A) mutant is correlated with the improvement of total protein synthesis and with the increased resistance to the protein synthesis inhibitor hygromycin B. Finally, the polysome profile defect of the eIF5A(K56A) mutant is largely corrected by high-copy eEF2. Therefore, these results demonstrate that eIF5A is closely related to eEF2 function during translation elongation.

Electron orbits under the external vertical field (BV) and the self poloidal field of the toroidal plasma current in a toroidal geometry are investigated by using analytic model fields in order to search for the conditions of occurence of appropriate confinement asymmetry of fast electrons along the field lines. This asymmetry efficiently and quickly generates a toroidal current, which may close the field lines in ECH-started plasmas. It is analytically shown that the characteristics of confinement asymmetry depend on the product of the major radius and the strength of the external vertical field. The results suggest that in large devices BV should be lowered and also some artificial means to speed up the pitch angle scattering for the fast electrons at a higher energy range are beneficial to generate the toroidal current in order to close the filed lines.

We have developed a digital signal processing module (APV7109) for a germanium semiconductor detector. The benchmark test of this module has shown good energy resolution and high throughput compared with conventional analog modules. By adding an extension module, the APV7109 can perform more advanced on-line calculations using the pulse shapes delivered by the on-board programmable logic. Therefore, user defined algorithms for pulse shape analysis can be used to adapt this module to various applications. Tests have demonstrated the feasibility of this extensible design.

Made available in DSpace on 2013-08-12T18:06:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-01 Made available in DSpace on 2013-09-30T18:06:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:24:14Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T13:24:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Several protozoan parasites exist in the Trypanosomatidae family, including various agents of human diseases. Multiple lines of evidence suggest that important differences are present between the translational and mRNA processing (trans splicing) systems of trypanosomatids and other eukaryotes. In this context, certain small complexes of RNA and protein, which are named small nuclear ribonucleoproteins (U snRNPs), have an essential role in pre-mRNA processing, mainly during splicing. Even though they are well defined in mammals, snRNPs are still not well characterized in trypanosomatids. This study shows that a U5-15K protein is highly conserved among various trypanosomatid species. Tandem affinity pull-down assays revealed that this protein interacts with a novel U5-102K protein, which suggests the presence of a sub-complex that is potentially involved in the assembly of U4/U6-U5 tri-snRNPs. Functional analyses showed that U5-15K is essential for cell viability and is somehow involved with the trans and cis splicing machinery. Similar tandem affinity experiments with a trypanonosomatid U5-Cwc21 protein led to the purification of four U5 snRNP specific proteins and a Sm core, suggesting U5-Cwc-21 participation in the 35S U5 snRNP particle. of these proteins, U5-200K was molecularly characterized. U5-200K has conserved domains, such as the DEAD/DEAH box helicase and Sec63 domains and displays a strong interaction with U5 snRNA. Univ Estadual Paulista, Fac Ciencias Farmaceut, Dept Ciencias Biol, Araraquara, SP, Brazil Univ Estadual Paulista, Inst Quim, Araraquara, SP, Brazil Univ São Paulo, Fac Med Ribeirao Preto, Ctr Quim Prot, Ribeirao Preto, SP, Brazil Univ São Paulo, Fac Med Ribeirao Preto, Ctr Reg Hemoterapia, Ribeirao Preto, SP, Brazil Univ Estadual Paulista, Fac Ciencias Farmaceut, Dept Ciencias Biol, Araraquara, SP, Brazil Univ Estadual Paulista, Inst Quim, Araraquara, SP, Brazil FAPESP: 06/05766-8 FAPESP: 07/07476-0 FAPESP: 08/56226-9

The L-H transition was observed in a unique helical divertor configuration where the core plasma is surrounded by ergodic layer, exhibiting rapid increase in edge electron density with sudden depre...

Several types of diagnostic system for soft X-ray radiation (SXR) have been developed and installed on the Large Helical Device (LHD). Magnetohydrodynamic (MHD) activities are studied by the fluctu...

Energetic ion-driven magnetohydrodynamic instabilities such as Alfven eigenmodes (AEs), energetic particle modes (EPMs), and their impacts on energetic ion confinement are being studied on the Larg...

A core density collapse (CDC) phenomenon is a rapid collapse events observed in super dense core (SDC) plasma with internal diffusion barrier (IDB) in the Large Helical Device (LHD). By CDC, the central beta is decreased by up to 50%. The collapse starts from the edge region of the plasma. CDCs appear with plasma parameters where the high–n ballooning modes are unstable at ϱ ∼ 0.8. With less collisional conditions, m = 1 type oscillations are observed with similar beta profile. The origin of the m = 1 oscillations is not clarified (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In the Large Helical Device (LHD), nonlinear evolution of strongly destabilized edge MHD modes, which are thought to be resistive interchange modes, induce repetitive bursts of magnetic fluctuations, soft X-ray (SX) fluctuations, and extreme ultra-violet (XUV) fluctuations, and generates a train of sharp spikes in Hα emission signals. These Hα spikes exhibit the character of edge localized mode (ELM). The ELM activities are also observed in high beta or high density L-mode plasmas having steep pressure gradient at plasma edge as well as H-mode plasmas with the L-H transition. The responsible instabilities for ELMs in LHD plasmas are thought to be resistive interchange modes, and are clearly different from those in a tokamak where peeling-ballooning modes are the candidates. The repetition frequency of ELMs (fELM) increases with the increase of external heating power, of which the character is similar to that of type I ELMs in tokamaks. The product of fELM and the relative ELM amplitude (δHα/Hα) is roughly in proportion to the input heating power, where the ELM induced loss energy (ΔWp) increases with δHα/Hα (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The present study aimed to evaluate the effect of the follicular population from cull Nelore (Bos indicus) on the kinetics of in vitro embryonic development. At random stages of the oestrous cycle (Day –5), a total of 28 cull Nelore cows were synchronized with an intravaginal progesterone device associated with oestradiol benzoate (2.0 mg IM). At the same moment, a dose of prostaglandin F2α (2.0 mg im) was also administered to promote luteolysis and absence of corpus luteum (CL) at the time of ovum pick-up (OPU). Five days later (Day 0), all cows underwent an OPU session and the recovered oocytes were submitted to in vitro embryo production (IVEP). The same procedures were repeated 2 times at 30-day intervals (Day 25 and Day 55). Semen from a single batch of a previously tested bull was used for all IVEP. Blastocyst production and hatching were verified on Days 7, 8, and 9 of the IVEP. Data were analysed by the GLIMMIX procedure of SAS 9.3® (SAS Institute Inc., Cary, NC, USA). Data of the 3 OPU sessions were grouped and the cows were classified into 3 categories according to the follicular population: Low (19.7 ± 0.9 follicles, n = 27), Medium (33.5 ± 0.8 follicles, n = 29), and High (58.7 ± 3.2 follicles, n = 28). The Low category had a lower rate of viable oocytes [(number of viable oocytes/total number of oocytes) × 100; 62.0 v. 69.5%; P = 0.02] and cleavage rate [(number of cleaved/total number of oocytes) × 100; 55.9 v. 66.8%; P = 0.001] than the High category. The blastocyst formation rate [number of blastocysts/total number of oocytes) × 100] on Day 7 and Day 8 was lower for Low and Medium compared with the High category (Day 7: 26.1b v. 29.0b v. 35.1a %; P = 0.001; and Day 8: 29.2b v. 30.2b v. 34.7a %; P = 0.05). No differences were found in blastocysts rate on Day 9 among Low, Medium, and High categories (14.1 v. 15.9 v. 16.2%; P = 0.61). However, Low category had a lower percentage of hatched blastocysts [(number of hatched blastocysts/number of blastocysts) × 100] on Day 7 compared with High category (2.9 v. 12.0%; P = 0.01). These results reported that cull Nelore with High follicular population showed higher rates of embryo production and hatched blastocysts compared with cows with Low follicular population. We concluded that the kinetics of in vitro embryonic development was compromised in cull Nelore (Bos indicus) with low follicular population submitted to OPU-IVEP. This research was supported by Fapesp 2012/50533–2 (GIFT).

In the large helical device (LHD) having three dimensional configuration, Alfven eigenmodes (AEs) destabilized by energetic ions are widely investigated using neutral beam heated plasmas with monotonic and non-monotonic rotational transform (ι/2π) profiles. In a plasma with monotonic ι/2π-profile, core-localized toroidicity-induced Alfven eigenmode (TAE) as well as global one are often observed. With the increase in the averaged toroidal beta value, defined as the ratio of total plasma pressure to toroidal magnetic pressure, core-localized TAE with low toroidal mode number becomes global. In a relatively high beta plasma with monotonic ι/2π-profile, two TAEs with different toroidal mode number often interact nonlinearly and generate another modes through three wave coupling. In a plasma with non-monotonic ι/2π-profile generated by intense counter neutral beam current drive, reversed shear Alfven eigenmode (RSAE) and geodesic acoustic mode (GAM) excited by energetic ions were observed for the first time in a helical plasma. Nonlinear coupling was also observed between RSAE and GAM.

A heavy ion beam probe (HIBP) using a 3-MV tandem accelerator has been installed on large helical device (LHD). Electrostatic potential in core plasma can be measured under the toroidal magnetic field strength of up to 3 T. By using the HIBP, the transition of potential profiles from electron-root to ion-root is observed in core plasmas during ramp-up of the electron density. Potential fluctuations are also measured electron cyclotron current drive (ECCD). Two kind of characteristic fluctuations are observed. One is a reversed-shear-induced Alfven eigenmode (RSAE), whose frequency varies during the evolution of the rotational transform profile, and the other is with a constant geodeisc acoustic mode (GAM) frequency.

Drilling and production operations in sensitive areas require an effective and efficient waste management plan to minimize the impact on the environment, especially when environmental legislations are strict. Waste management is a decisive factor during oilfield planning operations from an environmental and economic perspective. Often, the waste management method used depends on the type of operation (exploratory drilling, development drilling or production) and the environmental regulations. The waste related to drilling operations can include solid waste such as drilling cuttings and chemical products used for drilling fluid preparation, and liquid waste such as drilling fluid, contaminated rainwater and rig washes. Production waste comprises (mainly) completion fluids, produced water and oil-contaminated fluids. Cutting re-injection (CRI) technology is an accepted method for disposal of drilling cuttings and drilling-associated liquids. Produced water is usually injected into a subsurface formation for final disposal or to maintain reservoir pressure during production. According to conventional oilfield practices, both disposal options occur separately in different wells. Currently, commingled injection of both drilling cuttings and produced water in a same well is an interesting option if it is properly addressed. The article presents the commingled re-injection of cuttings and produced water during the development stage of the Pirana field as a cost-effective and environmentally friendly waste management method. The development of the Pirana field began in 2013 with seven producer wells and one injector well. During the 2013 campaign, the injector well was dedicated to only the re-injection of cuttings. After production started (at the end of 2013), the well was dedicated to only produced water injection until the beginning of the second drilling campaign (in 2014), where five additional wells were drilled and commingled injection began in the same injector well. Produced water was injected with periodic injections of drilling waste.

On the Large Helical Device (LHD), low to high confinement (L–H) transition and edge transport barrier (ETB) formation were observed in the low beta regime (βdia 1.5%). In most of ETB plasmas electron density preferentially increases in the edge region without a substantial rise of the edge electron temperature. The ETB zone develops inside the ergodic field layer calculated in the vacuum field. The ETB formation strongly destabilizes edge coherent modes such as m/n = 2/3 or 1/2 (m, n: poloidal and toroidal mode numbers), because the plasma edge region is in the magnetic hill. The ETB is partially destroyed by the combination of these edge MHD modes and ELM-like activities. For a particular experimental condition, the forced generation of a sizable m/n = 1/1 magnetic island near the edge by application of external field perturbations facilitates the L–H transition at a lower electron density and suppresses edge MHD modes and ELM-like activities to lower levels.

In the Large Helical Device (LHD), edge coherent MHD modes such as m/n = 2/3 or 1/2 (m, n: poloidal and toroidal mode numbers), of which the rational surface is located in the plasma edge region of the magnetic hill, are strongly enhanced after an L-H transition. In this case, an edge MHD mode localized in a region further in than the location of the enhanced MHD modes is often stabilized because of the decrease in the pressure gradient there. Enhancement of the edge MHD mode amplitude stops a substantial rise in the edge pressure gradient after the transition. In an L-H transition plasma, soft x-ray (SX) fluctuations, δI sx , related to edge MHD modes are clearly detected. The radial profiles of the amplitude and the phase differences among the SX-detector channels are sensitively dependent on the m-number. The relative amplitudes of the SX fluctuations, δI sx /I sx , which may reflect the eigenfunction of the MHD mode, rapidly increase towards the plasma edge in which the relevant rational surface exists.

On the Large Helical Device (LHD) where nested magnetic surfaces are surrounded by the ergodic field layer, edge transport barrier (ETB) was produced in neutral-beam-injection (NBI) heated plasmas through transition and non-transition processes. The former case is the ETB formation by L-H transition, where characteristics of L-H transition observed in a tokamak plasma are clearly recognized. The confinement improvement is the modest (~ 10%), compared with the ISS95 international stellarator scaling. The threshold power for the transition is comparable or slightly lower than the ITER scaling law established by tokamaks and compact tori. The ETB is formed inside the ergodic field layer of the vacuum field. The ETB formation destabilizes edge coherent modes such as m/n = 1/1, 2/3 and 1/2, of which rational surfaces are in the magnetic hill. The formed ETB is partially and transiently destroyed by these coherent edge MHD modes and edge localized modes (ELMs) typically observed in Hα signals. The latter ETB is observed in a plasma with large reversed NBI-driven current more than 100 kA at Bt = 1 T. In these plasmas, the edge magnetic shear is enhanced by the current and the rotational transform in the core region is expected to be appreciably reduced. Thus reduced rotational transform in the plasma central region will enhance outward heat and particle fluxes toward ergodic edge layer. The ETB with steep electron temperature gradient up to ~ 5 keV/m is formed by blocking enhanced outward heat flux.

Spatial and temporal variation in Microcystis species composition and microcystin concentration, quantified by enzyme-linked immunosorbent assay and high-performance liquid chromatography, were investigated during a 3-year period (1998-2000) in the Northern Basin of Lake Biwa. The Northern Basin generally had a concentration of 5 microg L(-1) or less, except at station 1 (Nagahama Bay) from July to October during the study period. The maximum concentration at station 1 was 22.7, 35.9, and 22.0 microg L(-1) in October of 1998, 1999, and 2000, respectively. Eleven species of cyanobacteria were observed: Microcystis aeruginosa, M. ichthyoblabe, M. novacekii, M. wesenbergii, Oscillatoria raciborskii, Anabaena oumiana, A. affinis, A. flos-aquae, A. ucrainica, A. smithii, and A. crassa. Of these, M. aeruginosa and M. wesenbergii were the main components observed. A high concentration of microcystin in the lake water was mostly a result of variation in the relative amount of toxic M. aeruginosa rather than of the total Microcystis cell number. This was supported by the analytical results for isolated strains. Microcystis spp. cell density in the Northern Basin appeared to increase gradually over the course of the study. This is the first study to have surveyed the Northern Basin of Lake Biwa, which supplies drinking water to 14 million people and is the largest lake in Japan.

The biosynthetic origin of the C-12 methyl group in homoanatoxin-a (1) was identified by the feeding experiment of L-[methyl-13C]-methionine in the culture of the cyanobacterium Raphidiopsis mediterranea Skuja strain LBRI 48. Remarkably high incorporation (80%) of 13C was observed at C-12. The in vivo enzymatic transformation of 1 was also examined by the prolonged culture of strain LBRI 48. The cells harvested at the stationary phase (15 days of incubation) gave higher contents of 4S-hydroxyhomoanatoxin-a (2), 4R-hydroxyhomoanatoxin-a (3), 2,3-epoxyhomoanatoxin-a (4), and 4-ketohomoanatoxin-a (5) than those from the cells collected at the late logarithmic growth phase (5 days). Compounds 2-5 would be transformed from 1 in the cells. The ratio of anatoxin-a and 1 was not significantly changed between two phases. Compound 5 was generated from 1 by air oxidation during storage even under dry and cool (-30 degrees C) conditions, but the oxidation was prevented in a water solution at both room temperature and -30 degrees C (frozen stock). Homoanatoxin-a (1) gave 2,3-dihydro-3-methoxyhomoanatoxin-a (6) during the separation procedures probably by the Michael reaction of methanol used as solvent. It should be noted that 4 was isolated for the first time from a cyanobacterium as the natural product. Compounds 3 and 5 were new members of the anatoxins.

Seasonal changes in microcystin concentrations in a resident snail (Sinotaia histrica) and an edible clam (Corbicula sandai) in Lake Biwa were surveyed. To clarify both the accumulation and depuration of microcystins, experimental studies with microcystin were also carried out on the snail. In the field investigation, microcystin was detected from the hepatopancreas and intestine of S. histrica (up to 3.2 µg g−1 dry weight and 19.5 µg g−1 dry weight, respectively); however, no microcystin was detected in the hepatopancreas of C. sandai. In the laboratory experiment, the microcystin-LR concentration in the hepatopancreas of S. histrica reached a value of 436 µg g−1 dry weight on day 10 of 15 days of uptake, and a high value persisted despite a depuration period of 15 days. The depuration rate constant of microcystin and its biological half-life were 0.0828 day−1 and 8.4 days, respectively. These results indicate that S. histrica has a high ability to accumulate microcystin in its tissue. Because S. histrica is predated by fish and water fowl, it is likely to play an important role as a vector for microcystin in lakes with dense blooms of toxic cyanobacteria.

We evaluated radiofrequency ablation (RFA) as a new local treatment for pelvic recurrence of rectal carcinoma. Fourteen lesions in 10 patients were treated by RFA. Four patients with a solitary recurrent tumor were treated curatively, while 10 lesions in the remaining 6 patients with distant metastases were treated palliatively mainly to control pain. RFA was performed under CT guidance and epidural anesthesia. It was carried out by a single insertion for tumors 3 cm or less in diameter or by multiple insertions for tumors greater than 3 cm. Ablation effectiveness was evaluated by magnetic resonance imaging. For palliative cases, severity of pain was assessed using a visual analogue scale. Needle placement and ablation were accomplished in all 14 lesions. Complications following RFA consisted of 2 cases of abscess formation, 2 cases of neuralgia and one case of bleeding. To obtain complete necrosis, the tumor should be under 4 cm in diameter and not involve any major iliac vessels. Three of 4 patients treated curatively met these conditions. Among these 4 patients, only one recurrence was observed after RFA (follow-up, 6–36 months). Five of 6 patients treated palliatively had tumours greater than 4 cm in diameter or involving iliac vessels. In none of the patients did we achieve complete necrosis and satisfactory analgesia. Although certain conditions must be met, RFA is a feasible and effective treatment, and it should be considered as one of the treatment options for pelvic recurrence of rectal carcinoma.

A neurotoxin, homoanatoxin-a, was isolated and characterized from a strain of the cyanobacterium Raphidiopsis mediterranea (from the Lake Biwa Research Institute, designated as LBRI 48) isolated from Lake Biwa, Japan. The toxicity of the lyophilized cells was estimated at 330 mg kg−1 by intraperitoneal injection in mice. A toxic substance was extracted with a methanol–water mixture (4:1) and separated by an octadecylsilanated silica gel (ODS) cartridge, followed by high-performance liquid chromatography purification (ODS, 17% methanol–water containing 0.05% trifluoroacetic acid). Signs of toxicity observed following lethal doses of the cell extract and the toxin were intense body paralysis, convulsions, gasping, dyspnea, and death in 5–10 min. The toxin was identified, based on its ultraviolet absorption spectrum (maximum at 230 nm), fast atom bombardment mass [(M + H)+ at m/z 180], and 1H-nuclear magnetic resonance spectral data, as homoanatoxin-a, which has previously been identified only from ...

The longitudinal axial strain in the plastic hinge regions of reinforced concrete (RC) structures has a significant influence on the behavior of RC structures subjected to reversed cyclic loading. This strain affects energy dissipation in the hysteretic response by causing the sliding along interconnecting wide flexural cracks. In addition, the strain also reduces the effective compressive strength of cracked concrete of the RC members, such as coupling beams, dominated by shear action. The research reported in this paper proposes a model to predict the axial strain in the plastic hinge regions of RC beams. The proposed model includes four path types: Path 1, pre-flexural yielding or unloading region; Path 2, post-flexural yielding region; Path 3, slip region; and Path 4, repeated loading region. In addition, this paper provides an equation to predict the longitudinal axial strain in the plastic hinge regions subjected to reversed cyclic loading of various patterns. To verify the longitudinal strain in the plastic hinge region by the proposed method, twelve RC beams were tested under reversed cyclic loading. The observed longitudinal strains in the plastic hinge regions of the tested beams agreed reasonably with the calculated longitudinal strains.

The aim of the present study was to evaluate the effect of bovine somatotropin (bST; 500mg) administration on lactating buffalo donors submitted to two different ovum pick-up (OPU) and in vitro embryo production schemes with a 7 or 14d intersession OPU interval. A total of 16 lactating buffalo cows were randomly assigned into one of four experimental groups according to the bST treatment (bST or No-bST) and the OPU intersession interval (7 or 14d) in a 2×2 factorial design (16 weeks of OPU sessions). The females submitted to OPU every 14d had a larger (P0.001) number of ovarian follicles suitable for puncture (15.6±0.7 vs. 12.8±0.4) and an increased (P=0.004) number of cumulus-oocyte complexes (COCs) recovered (10.0±0.5 vs. 8.5±0.3) compared to the 7d interval group. However, a 7 or 14d interval between OPU sessions had no effect (P=0.34) on the number of blastocysts produced per OPU (1.0±0.1 vs. 1.3±0.2, respectively). In addition, bST treatment increased (P0.001) the number of ovarian follicles suitable for puncture (15.3±0.5 vs. 12.1±0.4) but reduced the percentage (18.9% vs. 10.9%; P=0.009) and the number (1.4±0.2 vs. 0.8±0.1; P=0.003) of blastocysts produced per OPU session compared with the non-bST-treated buffaloes. In conclusion, the 14d interval between OPU sessions and bST treatment efficiently increased the number of ovarian follicles suitable for puncture. However, the OPU session interval had no effect on embryo production, and bST treatment reduced the in vitro blastocyst outcomes in lactating buffalo donors.

The relationship between Microcystis composition and the production of microcystins and nontoxic peptides in bloom cells, which was regularly collected in Lake Suwa, Japan, in the summer season from 1991 to 1994, was investigated. In order to determine the structures of the nontoxic peptides, we collected large amounts of bloom materials from the same lake on July 23, 1991, and isolated three nontoxic peptides. They were named as aeruginopeptins 917S-A, -B, and -C, and their structures were mainly determined by a mass spectrometry/mass spectrometry (MS/MS) technique as 19-membered cyclic depsipeptides possessing the Ahp (3-amino-6-hydroxy-2-piperidone) moiety. An analysis of the microcystins and aeruginopeptins in the collected blood cells and their Microcystis composition suggested that the M. aeruginosa large cell size produces both microcystins and aeruginopeptins, and the production of both compounds is genetically closely related.

The rheological behavior of polypropylene, PP, ethylene-propylene copolymer, EPR, and EPR/PP blends was studied. Zero-shear viscosity and elastic relaxation time were determined by least-squares fits by using a Carreau–Yasuda model with Arrhenius temperature dependency. The effect of PP and EPR molecular weight, ethylene ratio in EPR copolymer (E/EPR), and EPR concentration on the zero-shear viscosity and elasticity of EPR/PP blends was determined experimentally. Molecular weight effects are compared to theoretically expected relationships. EPR concentration effect and E/EPR ratio effects agree well with predictions made by using the Tsenoglou model. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2113–2127, 2001

Eight new linear peptides, microginins 478 ( 1 ), 51-A ( 2 ), 51-B ( 3 ) and 91-A ( 4 ) to 91-E ( 8 ), congeners of microginin, were isolated from the cyanobacterium Microcystis aeruginosa . These structures were elucidated to be 1 – 8 on the basis of 2D NMR data and chemical degradation. These peptides inhibited aminopeptidase M ( 1 , 2 and 6 – 8 ) and angiotensin-converting enzyme ( 1 ). The structure–activity relationship within a series of degradation and derivative products of microginin was investigated by the chemical studies.

Transcoding proxies for mobile World Wide Web access have been developed. In the near future, wideband mobile communication systems such as IMT-2000 will emerge, and these proxies will have to cope with a variety of media such as video. In this article we identify issues involved in viewing a video stream in a mobile computing environment; to handle these issues, we propose a video transcoding system and its control method. These mechanisms provide stable transmission of video data and comfortable video viewing on user clients by estimating the communication conditions, client device capabilities, and user preferences.

Electrospray ionization mass spectrometry was used to develop a rapid, sensitive, and accurate method for determination and identification of hepatotoxic microcystins, cyanobacterial cyclic heptapeptides. To optimize the electrospray ionization conditions, factors affecting charge state distribution, such as amino acid components of sample, proton affinity of the additives, and additive concentration, were investigated in detail and a method for controlling charge states was developed to provide molecular-related ions for assignment of molecular weight and reasonably abundant precursor ions for MS/MS analysis. A procedure for identification of microcystins consisting of known amino acids was proposed: for microcystins giving abundant [M + 2H]2+ ions, the addition of nitrogen-containing bases to the aqueous sample solution is effective to obtain an increased intensity of [M + H]+ ions, whereas the addition of Lewis acids containing nitrogen can produce increased abundances of [M + 2H]2+ ions for microcystins giving weak [M + 2H]2+ ions. Microcystins possessing no arginine residue always give sodium adduct ions [M + Na]+ as the base peak, and these are difficult to fragment via low energy collision-induced dissociation to yield structurally informative products; the addition of oxalic acid increases [M + H]+ ion abundances, and these fragment readily.

Two steps are usually involved in producing high impact polypropylene copolymer in a continuous process. The first is to polymerize propylene using Ziegler-Natta type or more recently metallocene catalyst, and the second is to add ethylene-propylene rubber (EPR). A narrow residence time distribution (RTD) of polymer particles is an important process design and operational target in this process. The broadening of RTD will lead to a widening of copolymer composition distribution in which results in inferior product properties. There are several techniques to obtain a narrower RTD, including by controlling size of particles leaving a well-mixed reactor. In this paper, a dynamic population balance model to track polymer particle age and size is presented. The model is applied to a well-mixed slurry reactor linked to a classifier. Polymer particle growth kinetics including catalyst deactivation with particle age are incorporated. The model agrees well with steady-state analytical solutions and process data for particle age and catalyst efficiency. The classifier acts to significantly narrow particle age distribution. However, the system is very sensitive to small change in feed catalyst size, catalyst deactivation can cause build up of small polymer particles trapped in the system if the feed catalyst size is too low. As a 'soft sensor', the RTD information from the validated model provides valuable insight for operational support. Further applications include strategies of reactor control design and optimization of grade transition policy. (C) 1999 Elsevier Science Ltd. All rights reserved.

An organic solvent-stable protease (PST-01 protease) in a culture broth of organic solvent-tolerant Pseudomonas aeruginosa PST-01 was purified by successive hydrophobic interaction chromatography using Butyl-Toyopearl gels. The purified enzyme was homogeneous as determined by SDS-polyacrylamide gel electrophoresis. PST-01 protease had a molecular mass of 38 kDa. The optimum temperature and pH for casein hydrolysis were 55 degrees C and 8.5, respectively. PST-01 protease was stable at pH 8-12 and below 50 degrees C and was determined to be a metalloprotease which was inhibited by EDTA, 1,10-phenanthroline, and phosphoramidon. PST-01 protease inhibited by EDTA was reactivated completely by the addition of zinc or cobalt ions. The stability of PST-01 protease in solutions containing water-soluble organic solvents or alcohols was higher than that in the absence of organic solvent. Furthermore, in general, PST-01 protease was more stable than commercially available proteases, namely, subtilisin Carlsberg, thermolysin, and alpha-chymotrypsin, in the presence of water-soluble organic solvents or alcohols.

The invention of a new catalyst, Metallocenes, which is highly active, selective and able to control polymer structure more precisely than the ordinary catalyst, leads the polyolefin polymer production to a new catalyst revolution. However, because the catalyst is sensitive to temperature, it pushes the plant to operate at an open-loop unstable point. This paper deals with a design problem of temperature controller for an industrial polypropylene polymerization reactor, which is open-loop unstable when the new catalyst is used. The dynamics of the open-loop unstable process is identified by a first order system with integral and dead time element. Then, the controller is realized in an I-PD structure. The application result illustrates that the developed controller can successfully stabilize the plant.