Part Of S2 Research Articles

Global Regular Axially Symmetric Solutions to the Navier–Stokes Equations: Part 2

The axially symmetric solutions to the Navier–Stokes equations are considered in a bounded cylinder Ω⊂R3 with the axis of symmetry. S1 is the boundary of the cylinder parallel to the axis of symmetry, and S2 is perpendicular to it. We have two parts of S2. On S1 and S2, we impose vanishing of the normal component of velocity and the angular component of vorticity. Moreover, we assume that the angular component of velocity vanishes on S1 and the normal derivative of the angular component of velocity vanishes on S2. We prove the existence of global regular solutions. To prove this, the coordinate of velocity along the axis of symmetry must vanish on it. We have to emphasize that the technique of weighted spaces applied to the stream function plays a crucial role in the proof of global regular axially symmetric solutions. The paper is a generalization of Part 1, where the periodic boundary conditions are prescribed on S2. The transformation is not trivial because it needs to examine many additional boundary terms and derive new estimates.

Reparation of nano-FeS by ultrasonic precipitation for treatment of acidic chromium-containing wastewater

Nano-FeS is prone to agglomeration in the treatment of chromium-containing wastewater, and ultrasonic precipitation was used to synthesize nano-FeS to increase its dispersion. The optimization of the preparation method was carried out by single factor method (reaction temperature, Fe/S molar ratio and FeSO4 dropping flow rate) and response surface methodology. Dynamic experiments were constructed to investigate the long-term remediation effect and water column changes of nano-FeS and its solid particles. The changes of the remediation materials before and after the reaction were observed by SEM, and the mechanism of the remediation of chromium-containing wastewater by nano-FeS prepared by ultrasonication was revealed by XRD. The results showed that the reaction temperature of 12 °C, Fe/S molar ratio of 3.5 and FeSO4 dropping flow rate of 0.5 mL/s were the best parameters for the preparation of nano-FeS. The nano-FeS has efficient dispersion and well-defined mesoporous structure in the form of needles and whiskers of 40–80 nm. The dynamic experiments showed that the average removal of Cr(VI) and total chromium by nano-FeS and its immobilized particles were 94.97% and 63.51%, 94.93% and 45.76%, respectively. Fe2+ and S2− ionized by the FeS nanoparticles rapidly reduced Cr(VI) to Cr(III). Part of S2− may reduce Fe3+ to Fe2+, forming a small iron cycle that gradually decreases with the ion concentration. Cr(III) and Fe2+ form Cr(OH)3 and FeOOH, respectively, with the change of aqueous environment. Another part of S2− reacts with Cr(III) to form Cr2S3 precipitate or is oxidized to singlet sulfur. The FeS nanoparticles change from short rod-shaped to spherical shape. Compared with the conventional chemical precipitation method, the method used in this study is simple, low cost, small particle size and high removal rate per unit.

Global Regular Axially Symmetric Solutions to the Navier–Stokes Equations: Part 1

The axially symmetric solutions to the Navier–Stokes equations are considered in a bounded cylinder Ω⊂R3 with the axis of symmetry. S1 is the boundary of the cylinder parallel to the axis of symmetry and S2 is perpendicular to it. We have two parts of S2. For simplicity, we assume the periodic boundary conditions on S2. On S1, we impose the vanishing of the normal component of velocity, the angular component of velocity, and the angular component of vorticity. We prove the existence of global regular solutions. To prove this, it is necessary that the coordinate of velocity along the axis of symmetry vanishes on it. We have to emphasize that the technique of weighted spaces applied to the stream function plays a crucial role in the proof of global regular axially symmetric solutions. The weighted spaces used are such that the stream function divided by the radius must vanish on the axis of symmetry. Currently, we do not know how to relax this restriction. In part 2 of this topic, the periodic boundary conditions on S2 are replaced by the conditions that both the normal component of velocity and the angular component of vorticity must vanish. Moreover, it is assumed that the normal derivative of the angular component of velocity also vanishes on S2. A transformation from part 1 to part 2 is not trivial because it needs new boundary value problems, so new estimates must be derived.

High air-stability and superior lithium ion conduction of Li3+3xP1-xZnxS4-xOx by aliovalent substitution of ZnO for all-solid-state lithium batteries

A series of new solid electrolytes of Li3+3xP1-xZnxS4-xOx (x = 0.01, 0.02, 0.03, 0.04, 0.05, 0.06) are synthesized successfully via Zn, O co-doping the Li3PS4 glass-ceramic for the first time. The result shows that Li3PS4 aliovalent substitution of 2 mol% ZnO (Li3.06P0.98Zn0.02S3.98O0.02) presents the highest conductivity of 1.12×10−3 S cm−1 at room temperature, which is twice that of the pristine Li3PS4. Besides, Li3.06P0.98Zn0.02S3.98O0.02 exhibits excellent stability against humid air, lithium metal and chlorobenzene solvent. The mechanisms of the enhancement of conductivity and air-stability are well understood by conducting first-principles density functional theory (DFT) calculation and Bond-Valence (BV) analysis, and the results well demonstrate that the conductivity and air-stability of Li3PS4 could be improved via Zn, O dual-doping, in which partial P5+ could be substituted by Zn2+, and a part of S2- could be replaced by O2-. Finally, the all-solid-state lithium battery (ASSLB) with bi-layer electrolytes of LiCoO2/Li10GeP2S12/Li3.06P0.98Zn0.02S3.98O0.02/Li is assembled, and it delivers an initial discharge capacity of 139.1 mAh g−1 at 0.1 C and a capacity retention of 81.0% after 100 cycles at room temperature. This work combines systematical experimental characterizations and sufficient theoretical calculations to develop a new promising sulfide electrolyte with superior lithium ion conductivity and high air-stability for ASSLBs application.

In situ detection of laccase activity and immunolocalisation of a compression-wood-specific laccase (CoLac1) in differentiating xylem of Chamaecyparis obtusa.

The secondary cell wall of compression wood tracheids has a highly lignified region (S2L) in its outermost portion. To better understand the mechanism of S2L formation, we focussed on the activity of laccase (a monolignol oxidase) and performed in situ studies of this enzyme in differentiating compression wood. Staining of differentiating compression wood demonstrated that laccase activity began in all cell wall layers before the onset of lignification. We detected no activity of peroxidase (another monolignol oxidase) in any cell wall layer. Thus, laccase likely plays the major role in monolignol oxidisation during compression wood differentiation. Laccase activity was higher in the S2L region than in other secondary wall regions, suggesting that this enzyme was responsible for the high lignin concentration in this region of the cell wall. Immunolabelling demonstrated the expression of a compression-wood-specific laccase (CoLac1) immediately following the onset of secondary wall thickening, this enzyme was localised to the S2L region, whereas much less abundant in the S1 layer or inner S2 layer. Thus, the CoLac1 protein is most likely localised to the outer part of S2 and responsible for the high lignin concentration in the S2L region.

Cross-company vs. single-company web effort models using the Tukutuku database: An extended study

In 2004 [Kitchenham, B.A., Mendes, E., 2004a. Software productivity measurement using multiple size measures. IEEE Transactions on Software Engineering 30 (12), 1023–1035, Kitchenham, B.A., Mendes, E., 2004b. A comparison of cross-company and single-company effort estimation models for web applications. In: Proceedings Evaluation and Assessment in Software Engineering (EASE’ 04), pp. 47–55] (S1) investigated, using data on 63 Web projects, to what extent a cross-company cost model could be successfully employed to estimate development effort for single-company Web projects. Their effort models were built using Forward Stepwise Regression (SWR) and they found that cross-company predictions were significantly worse than single-company predictions. This study S1 was extended by Mendes and Kitchenham [Mendes, E., Kitchenham, B.A., 2004. Further comparison of cross-company and within company effort estimation models for web applications. In: Proceedings International Software Metrics Symposium (METRICS’04), Chicago, Illinois, September 11–17th, 2004. IEEE Computer Society, pp. 348–357] (S2), who used SWR and Case-based reasoning (CBR), and data on 67 Web projects from the Tukutuku database. They built two cross-company and one single-company models and found that both SWR cross-company models and CBR cross-company data provided predictions significantly worse than single-company predictions. Since 2004 another 83 projects were volunteered to the Tukutuku database, and recently used by Mendes et al. [Mendes, E., Di Martino, S., Ferrucci, F., Gravino, C., in press. Effort estimation: How valuable is it for a web company to use a cross-company data set, compared to using its own single-company data set? In: Proceedings of International World Wide Web Conference (WWW’07), Banff, Canada, 8–12 May] (S3), who partially replicated Mendes and Kitchenham’s study (S2), using SWR and CBR. They corroborated some of S2’s findings (SWR cross-company model and the CBR cross-company data provided predictions significantly worse than single-company predictions) however they replicated only part of S2. The objective of this paper (S4) is therefore to extend Mendes et al.’s work and fully replicate S2. We used the same dataset used in S3, and our results corroborated most of those obtained in S2. The main difference between S2 and our study was that one of our SWR cross-company models showed significantly similar predictions to the single-company model, which contradicts the findings from S2.

Anatomia do nervo isquiático em mocós (Kerodon rupestris WIED, 1820) aplicada a clínica de animais silvestres

Para conhecer a origem do nervo isquiático de mocós (Kerodon rupestris WIED,1820) junto aos forames intervertebrais e a musculatura envolvida em seu trajeto, foram utilizados 10 animais adultos, oriundos do Centro de Multiplicação de Animais Silvestres da Escola Superior de Agricultura de Mossoró (CEMAS-ESAM). Após o óbito natural, estes foram fixados em formol a 10%, e foram dissecados para exposição e visualização do nervo isquiático. Os resultados foram expressos em percentual. Foram verificadas variações na quantidade de vértebras lombares e sacrais. Cinco animais (50%) apresentaram sete vértebras lombares e três sacrais, dois (20%) apresentaram sete vértebras lombares e quatro sacrais, e dois (20%) apresentaram seis vértebras lombares e três sacrais. Um animal (10%) apresentou seis vértebras lombares e quatro sacrais. Portanto, a origem do nervo foi diferenciada. Cinco animais (50%) tiveram a participação de L7, S1, S2; dois animais (20%) L7, S1, com pequena contribuição de S2. Dois animais (20%), de L6, S1, S2; e um animal (10%), de L6, S1 com uma pequena contribuição de S2. A última raiz do nervo isquiático em todas as suas origens, contribuiu para a formação da primeira raiz do nervo pudendo. Constatou-se que ao longo de seu trajeto os nervos isquiáticos cederam ramos para os músculos glúteo médio, glúteo profundo, glúteo surpeficial, emitindo ramos musculares para o bíceps femoral ou da coxa, e para os músculos semimembranoso e semitendinoso, que continua com um tronco calibroso, originando os nervos fibular lateralmente, medialmente o tibial e caudalmente o cutâneo sural plantar lateral.

Identification of proximal tubule segments in the mouse nephron by simultaneous visualization of alkaline phosphatase and γ-glutamyl transpeptidase

ALP and gamma-GT are 2 brush border enzymes that can be individually demonstrated on adjacent sections by the histochemical methods of Mayahara (ALP) and Rutenberg (gamma-GT). On the basis of each enzyme activity, it was possible to recognize different categories of tubules in the mouse nephron. In fact, both enzymes were heterogeneously distributed along the proximal tubule, but in opposite gradients. The various staining intensities probably corresponded to proximal segmentation, but were sometimes difficult to evaluate. A technique was perfected to localize both enzymes in the same tissue section. Since each enzyme produced a distinct type of colored precipitates (ALP: black, gamma-GT: red), 4 categories of tubules could be identified, according to staining characteristics: 1. black tubules where ALP activity was predominant, corresponded to S1 segments, 2. black and red tubules where the 2 activities were about equivalent, were considered as parts of S2, 3. red ones where gamma-GT activity was high, were identified as portions of S3, 4. negative tubules where no activity was apparent, represented distal and straight collecting tubules. In addition to economize time and tissue, this simple technique permits to easily estimate variations in enzyme activities that probably correspond to structural and functional differences in the segments of the proximal tubule.

Heterogeneous distribution of alkaline phosphatase and γ-glutamyl transpeptidase in the mouse nephron

In the mouse nephron, ALP and gamma-GT were found to be heterogeneously distributed along the proximal tubule. For both enzymes, 4 large categories of tubules could be recognized on the basis of the enzymatic activity: intense; intermediate; weak; negative. The localization of ALP and gamma-GT was in opposite gradient along the proximal tubule and it apparently corresponded to the 3 sequential segments S1, S2, and S3. In fact, S1 could be identified with certainty because this first portion was often seen attached to the renal corpuscle. This segment displayed a very intense ALP activity (category 1), but a weak one for gamma-GT (category 3). Intermediate tubules for ALP and gamma-GT activities (category 2) seemingly were parts of S2. Those tubules where ALP activity was weak (category 3) while that of gamma-GT was intense (category 1) probably belonged to S3. As a result, it becomes possible to clearly distinguish the segments S1, S2, and S3, not only on a structural and biochemical basis but as well by the localization of brush border enzymes. Distal tubules showed no enzyme activity (category 4). In other respects, the presence of ALP and gamma-GT on the parietal layer of Bowman's capsule strongly suggests that these tall cylindrical cells are morphologically and enzymatically identical to those of the S1 segment, and that they might have similar functional roles.

Studies on compression wood—part VII: Distribution of lignin in normal and compression wood of tamarack [Larix laricina (Du Roi) K. Koch

The distribution of lignin has been studied in tracheids and ray cells of normal and compression wood of tamarack [Larix laricina (Du Roi) K. Koch]. The three layers in the secondary wall of normal wood tracheids are lignified to approximately the same extent, and previous evidence that the S 3 layer should contain a higher proportion of lignin than the other regions has not been confirmed. The lignin follows closely the orientation of the cellulose microfibrils in all three layers. Compared to the tracheids, the ray cells contain a denser network of lignin in their secondary wall. Only a small proportion of the total lignin in compression wood tracheids is present in the compound middle lamella. The thick S 1 layer is only slightly lignified; the orientation of the lignin in this region is that of the transversely oriented, lamellated microfibrils. The outer portion of S 2 consists largely of lignin but also contains lamellae of cellulose microfibrils which probably have the same helical orientation as the microfibrils in the inner part of S 2. The latter region, which contains the helical cavities, consists of lamellae of cellulose microfibrils which are uniformly encrusted with lignin. The ray cells in compression wood appear to be lignified to the same extent as in normal wood. Transverse sections of the cells reveal a lateral orientation of the lignin. The orientation of the cellulose microfibrils in the S 2 layer of the first-formed springwood tracheids of compression wood is the same as in the cells which are formed later. It is suggested that for ease of reference, the outer, lignin-rich layer in compression wood tracheids be referred to as the S 2(L) layer.

Untersuchungen über Druckholzbildung—Erste Mitteilung: Die Verteilung des Lignins im Druckholz von Fichte (Picea rubens Sarg.)

Normal and compression wood from red spruce (Picea rubens Sarg.) and, to a limited extent, balsam fir (Abies balsamea (L.) Carr.) was subjected to treatment with hydrofluoric acid and decay by the brown rot fungiLenzites trabea Persoon ex Fries andLenzites saepiaria Wulfen ex Fries. The texture and distribution of the lignin remaining after these treatments were studied in transverse and longitudinal sections by electron microscopy. In agreement with previous investigations, the lignin in the secondary wall of normal tracheids was found to form a continuous network. The results obtained with compression wood tracheids showed that there was an isotropic layer with a high lignin concentration located immediately insideS 1, but that this region also contained polysaccharides which were probably oriented in a transverse direction with respect to the fiber axis. The inner part ofS 2, containing the helical cavities, had a uniform distribution of lignin in the form of a continuous network. There was no evidence for a radial distribution of lignin in compression wood tracheids nor for the absence of lignin from the inner portion ofS 2, as had been stated by earlier investigators. The polysaccharides in the cell wall of the compression tracheids, and especially those located in the outer part ofS 2, were partially inaccessible to both acids and fungi. The latter penetrated the wood both through the lumens and through the intercellular spaces.Lenzites saepiaria was by far the more efficient of the two fungi used.