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Experiments designed to determine the characteristics of SBR/carbon black wet masterbatch (WMB) are described. Compared to dry-mixed compounds, WMB-mixed compounds show a higher level of SBR-molecular-motion restriction. WMB-mixed compounds also display longer fatigue life and superior reinforcement and have larger fracture-surface energy than do dry-mixed compounds., By Kazuhiro Sone, M. Ishida, M. Ishiguro and T. Hatta, Mitsubishi Kasei and Kunihiko Fujimoto, Shibaura Institute of Technology Among the particle fillers which reinforce elastomers, carbon black is one [...]

Eimeria tenella is recognized worldwide as a significant pathogen in the poultry industry. However, a lack of methods for isolating developing schizonts has hindered the use of transcriptome analyses to discover novel and developmentally regulated genes. In the present study, we characterized the long-term successive development of E. tenella in infected chicken caeca and assessed the utility of laser microdissection (LMD) for the isolation of schizont RNA. Developmental stages, including those of the first, second, and third-generation schizonts and gametocytes, were synchronous. Using LMD, only the mature second-generation schizonts were successfully excised from the lamina propria, and non-degraded RNA was purified from the schizonts. E. tenella-specific genes were amplified by reverse transcription polymerase chain reaction (RT-PCR). These results augment our understanding of the E. tenella life cycle, and reveal LMD as a potentially useful tool for gene expression analyses of the intracellular stages of E. tenella. [ABSTRACT FROM PUBLISHER]

OBJECTIVE: This open-label, randomized controlled trial investigated the effects of cilnidipine, an L/N-type calcium channel blocker (CCB), in patients with chronic kidney disease (CKD). METHODS: Sixty patients with CKD and well-controlled hypertension being treated with a renin—angiotensin system (RAS) inhibitor and an L-type CCB (L-CCB) were randomly assigned either to switch from the L-CCB to cilnidipine after a 4-week observation period or to continue with L-CCB treatment. Blood pressure, heart rate and renal function were monitored for 12 months. Data were available for analysis from 50 patients: 24 from the cilnidipine group and 26 from the L-CCB group. RESULTS: Blood pressure was well controlled in both groups. After 12 months, proteinuria and heart rate were significantly decreased in the cilnidipine group, but proteinuria increased and heart rate remained unchanged in the L-CCB group. There was a significant positive correlation between the percentage changes in proteinuria and heart rate. CONCLUSIONS: Cilnidipine has antihypertensive effects equivalent to those of L-CCBs. In patients with CKD, proteinuria can be decreased by switching from an L-CCB to cilnidipine, thereby improving renal function.

The formation of biogenic silica quartz in the steady-state environment is a widespread phenomenon that is prerequisite for understanding biomineralization, diagenetic evolution, biogeochemical cycling, and reservoir formation, yet the mechanism is not fully understood. Here, the formation mechanism of silica quartz originated from diatom algae is investigated under low temperature/pressure conditions focusing on angstrom-scale pores. There exist 2 Å pores in amorphous silica acting as pathways of water diffusion with an activation energy of 2.3 eV. Water molecules react with highly reactive pore surfaces involving an energy cost of 1.9 eV, which triggers off the quartz formation. We show that the mechanistic theory of nucleation taking account of diffusion and reactions of water molecules in the angstrom-scale pores explains the long-term formation of biogenic silica quartz.

AbstractThe crystal structure of whewellite [Ca(C2O4)·H2O] and the dehydration mechanism of caoxite [Ca(C2O4)·3H2O] have been studied by means of differential thermal analysis, X-ray diffraction (powder and single-crystal) analysis and infrared analysis. The first and second analyses confirmed the direct transformation of caoxite into whewellite without an intermediate weddellite [Ca(C2O4)·2H2O] stage. Infrared spectra obtained from caoxite, weddellite and whewellite emphasize the similarity of the O–H-stretching band and O–C–O-stretching band in whewellite and caoxite and the unique bands of weddellite. The structure refinement at low temperature (123 K) reveals that all the hydrogen atoms of whewellite form hydrogen bonds and the two water molecules prop up the crystal structure by the hydrogen bonds that cause a strong anisotropy of the displacement parameter.Comparing the structural features of whewellite with those of weddellite and caoxite suggests that caoxite and whewellite have a sheet structure consisting of Ca2+ions and oxalate ions although weddellite does not. It is additionally confirmed that the sheets of caoxite are corrugated by hydrogen bonds but whewellite has flat sheets. The corrugated sheets of caoxite would be flattened by dehydration so the direct transformation of caoxite into whewellite would not occur via weddellite. Essential for this transformation is the dehydration of interlayered water molecules in caoxite leading to the building of the crystal structure of whewellite on its intralayered water molecules. The difference in conformation of water molecules between those two crystal structures may explain the more common occurrence of whewellite than of caoxite in nature.

Mouse embryos on embryonic day (E) 13 or 14 were treated with ACTH1–24 by exo uteromicroinjection and the adrenal was examined after 16 and 32 h. Light microscopic morphometry showed that the ACTH treatment increased cell size and decreased cell density of the adrenocortical cells. Bromodeoxyuridinelabeling index did not alter significantly after the ACTH treatment. By immunohistochemistry, both number of cells expressing 11β-hydroxylase and the staining intensity increased in the ACTH-treated glands compared to controls whereas expression of aldosterone synthase was detectable in neither the treated nor control groups. Ultrastructurally, the adrenocytes of the inner cortical zone of the ACTH-treated glands were characterized by strikingly increased content of the smooth endoplasmic reticulum, increased mitochondria with more vesicular cristae, lipid droplets with a much higher electron density along with the distribution altered from that in controls. All of the significant differences between the ACTH-treated and control glands occurred at 16 h but not at the 32 h interval. The present results indicated that the mouse fetal adrenocytes are already sensitive to ACTH during early period (E13 and 14) of their functional differentiation. In vivoacute treatment of ACTH stimulates cell-size, increase of fetal adrenocytes but not proliferation, and may directly or indirectly regulate multiple steps of the steroidogenic process of the fetal mouse adrenal.

AbstractThallium leucite, TlAlSi2O6, has been synthesized at 450°C for 7 days, under ambient conditions, by the transformation of dehydrated analcime NaAlSi2O6in the presence of excess TlCl. This substitution of Tl for Na leads to confirmation of a thallium-leucite pseudomorph after analcime. Their optical properties, X-ray powder diffraction patterns, electron microprobe analysis, infrared spectra, and X-ray photoelectron spectroscopy have characterized the synthetic Tl-leucites. The IR spectra show that the mid-IR modes T-Ostretching and T-O-Tbending vibrations for TlAlSi2O6are more resemblant of those for analcime than for leucite, KAlSi2O6. This resemblance implies that Tl cation enters the W-site rather than the S-site in the analcime structure: Na (S) + H2O (W) ? ? + K (leucite) ? ? + Tl (Tl- leucite), where ? represents an S-site vacancy. The mechanism of this substitution is supported by the crystal chemical constraints: inasmuch as the S-site is smaller than the W-site, Tl+cations being larger than Na+plainly prefer the latter site to the former. One inference from the binding energy for Tl+by XPS is that Tl+occupies the extra-framework site in synthetic leucite pseudomorph, rather than the smaller tetrahedral site. The difference in Al/Si disordering between analcime and leucite and the nonstoichiometry due to the solid solution of the ?Si3O6component into the leucite structure may provide a fundamental insight into understanding why TlAlSi2O6deviates from the trend defined by K-, Rb- and CsAlSi2O6leucite series on the a-cparameter diagram, inasmuch as these three cations in the leucite structure occupy the W-sites. Finally, synthesis of TlAlSi2O6leucite has an implication for the existence of other polymorphs due to different degrees of Al/Si disordering, except for high- and low-temperature leucites already known: natural leucites crystallized directly through igneous processes are different from those formed by substitution of K for Na in analcimes.

Weathering rates based on temporal changes in a variety of rock properties were examined for four dated lava domes made of porous rhyolite. The lava domes were erupted at 1.1, 2.6, 20 and 40 ka BP. The time from each eruptive event to the present provide elapsed weathering times. The lava domes have many cooling joints formed immediately after eruption. Joint-bounded blocks have a high porosity, resulting in deep weathering. The blocks have almost uniform characteristics from top to bottom in one outcrop. The mineralogical, chemical, physical and mechanical properties of the four rhyolites were analysed. These results show that the chemical properties and physical properties, including specific surface area, change slowly in the early stage of weathering (0–20,000 years) and quickly in the later stage (20,000–40,000 years), while mechanical strength and bulk density or porosity of the rhyolites change rapidly in the early stage and slowly in the later stage. Mechanical strength reduces by 70–90% relative to fresh rock in 40,000 years, although chemical and physical properties change by only 1023̄0 %. It is concluded that different weathering properties exhibit different rates and patterns of change over 40,000 years, and that mechanical strength is the property most susceptible to weathering.

We demonstrate the degradation of RNA bound to an antisense oligonucleotide by a reverse transcriptase enzyme-associated RNase H activity. We found that phosphorothioate oligonucleotides inhibit the RNase H activity by binding to AMV RT, rather than to the template RNA, whereas the RNase H activity of HIV-1 RT is not affected by the antisense phosphorothioate oligonucleotide. Selective inhibition of HIV-1 gene expression involves the degradation of the template RNA bound to the antisense phosphorothioate oligonucleotide by the RNase H activity associated with the HIV-1 polymerase.

We have demonstrated that antisense phosphorothioate oligonucleotides (S-ODNs) inhibit influenza A virus replication in MDCK cells. Liposomally encapsulated and free antisense S-ODNs with four target sites (PB1, PB2, PA and NP genes) were tested for their abilities to inhibit virus-induced cytopathogenic effects in a MTT assay using MDCK cells. The liposomally encapsulated S-ODN complementary to the site around the PB2 AUG initiation codon showed highly inhibitory effects. In contrast, the inhibitory effect of the liposomally encapsulated S-ODN targeted to PB1 was considerably decreased in comparison with that directed to the PB2 target site. The liposomally encapsulated antisense S-ODNs exhibited higher inhibitory activities than the free oligonucleotides, and showed sequence-specific inhibition, whereas free antisense S-ODNs were observed to inhibit viral adsorption to MDCK cells. Liposomal preparations of oligonucleotides facilitated their release from endocytic vesicles, and thus cytoplasmic and nuclear localization was observed. The activities of the antisense S-ODNs were effectively enhanced by using the liposomal carrier. Interestingly, the liposomally encapsulated FITC-S-ODN-PB2–as accumulated in the nuclear region of MDCK cells. However, weak fluorescence was observed within the endosomes and the cytoplasm of MDCK cells treated with the free antisense S-ODNs. The cationic lipid particles may thus be a potentially useful delivery vehicle for oligonucleotide-based therapeutics and transgenes, appropriate for use in vitroor in vivo.

Subjective moods of student nurses during the clinical practice training course in hospital were measured using the Stress Arousal Check List (J-SACL). The mental state of student nurses was evaluated on three occasions: on the first day in the morning and in the afternoon, and on the last day in the morning. The evaluated stress and arousal moods of students in the obstetrics and the aged care sections were compared. The results showed that students possessed strong stress and low arousal feelings at the beginning of the first day of clinical practice in obstetrics, whereas they felt no stress and relatively high arousal on the first day of clinical practice in the aged care section. The feelings of stress persisted throughout the day in the obstetrics section. These feelings decreased, however, during the two weeks' clinical practice. Based upon these findings, evaluation methods of students' subjective feelings and instructional suggestions for supervisors in clinical practice were discussed. © 1998 John Wiley & Sons, Ltd.

The present study examined kanji errors in handwriting made by Japanese students and Australian learners of Japanese. First, a cognitive psychological model to explain the production of writing errors was proposed based upon the analysis of 374 writing errors of two-morpheme (kanji) compound words generated by Japanese students in spontaneous sentence writing situations. Despite the common assumption that kanji writing errors may not be related to the sounds of kanji characters (i.e., morphological phonology), the present study found that phonologically-related kanji writing errors were most numerous (60.0%), followed by orthographically-related errors (43.6%) and semantically-related errors (29.7%), including some overlap of these three types. Second, 408 kanji writing errors made by students learning Japanese in an Australian university were analyzed. Unlike the Japanese students, these subjects wrote more non-existing kanji and made orthographically-related mistakes rather than semantically- and phonologically-related errors. This result must be related to the level of kanji writing skills held by learners of Japanese. In light of these results, several suggestions were proposed for the methods of teaching kanji writing.

Zusammenfassung: Die rechte Lunge kann den Ausfall der linken Lunge ohne Beanspruchung des Kreislaufes kompensieren. Fllt dagegen die rechte Lunge aus, so tritt eine entsprechende Kreislaufvernderung ein. Diese Erscheinung wird durch den Grenunterschied der beiden Lungen erklrt.

Antifungal substances were detected in leaves of 11 out of 27 Eucalyptus species examined. It was shown that antifungal substances found in the Eucalyptus species examined consist of from 1 to 4 different components.

Reaction of catechols such as (I), (III), (V), (VIII) or resorcinols such as (XI) with N4S4(IV) gives rise to thiadiazoles such as (II), (VII) and/or (VI), (XII) + (VI).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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 100 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.

The thiadiazole derivative (Ia) is brominated, giving the dibromide (Ib) as the main product.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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.

Under the optimized conditions shown in the scheme, treatment of the diols (Ia) and (Ib) with N4S4(II) yields exclusively the benzothiadiazole (III).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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.