Propagating solitons generated by localized perturbations on the surface of deep water

We report experimental evidence of the propagating capillary solitary waves generated by a localized water surface perturbation. Solitons are formed at the air-water interface with a solid plunger and then propagate with velocities proportional to their amplitudes. The shape of the forward front of such solitons is independent of the plunger shape and is given by the hyperbolic secant profile. We find that the nonlinearity of capillary waves is responsible for a small dispersion in the capillary wave group velocity and the soliton existence. This dispersion can be further reduced by adding minute concentrations of proteins to water.

Parametrically excited water surface ripples as ensembles of oscillons

We show that ripples on the surface of deep water which are driven parametrically by monochromatic vertical vibration represent ensembles of oscillating solitons, or quasiparticles, rather than waves. The horizontal mobility of oscillons determines the broadening of spectral lines and transitions from chaos to regular patterns. It is found that microscopic additions of proteins to water dramatically affect the oscillon mobility and drive transitions from chaos to order. The shape of the oscillons in physical space determines the shape of the frequency spectra of the surface ripple.

First Report of Artichoke Bacterial Stem Rot Caused by Pectobacterium carotovorum subsp. carotovorum in China

A new disease on globe artichoke (Cynara scolymus L.) was observed in the springs of 2008 and 2009 and during the spring and fall seasons of 2010 in commercial fields (nearly 1,000 ha) in Changde, Hunan Province, China. Characteristic symptoms were wilting and necrosis of the outermost leaves and dark brown discoloration of the vascular tissue and pith of the stem base. Eventually, the plants wilted and died. Nearly 5, 35, and 4% (2008, 2009, and 2010, respectively) of the artichoke fields were destroyed because of the disease. Manual weeding and cuttings often led to the development of typical soft rot during propagation. To investigate the causal agent of the disease, isolations were made from rotted stems of field artichoke plants on nutrient agar (NA). Bacteria consistently isolated from the diseased tissues formed gray-white, glossy, convex, translucent, and round colonies on NA. The bacterial cells were gram-negative rods with two to eight peritrichous flagella. Ten isolates were negative for oxidase, arginine dehydrolase, H₂S, gelatin liquefaction, and tryptophan ammonialyase. Isolates were positive for catalase, reduced NO₃ to NO₂, indole, glucuroide, galactosidase, Voges-Proskauer test, and β-galactosidase, along with being facultatively anaerobic and insensitive to erythromycin (40 μg/ml). Negative results were obtained for utilization of maltose, gluconate, and phenylacetic acid, and positive results were obtained from arabinose, glucose, mannose, N-acetyl-glucosamine, mannitol, and sodium citrate for all isolates. Acid was produced from glucose, inositol, rhamnose, melibiose, arabinose, mannitol, sucrose, and amarogentin. All test results were similar to reference strain PCC1000 (GenBank Accession No. JF721959) of Pectobacterium carotovorum subsp. carotovorum. These isolates could also cause soft rot of Chinese cabbage stem, carrot slice, pepper, lettuce and artichoke stems, and tomato and potato slices within 48 h at 28°C in an artificial inoculation test (3). PCR amplification was carried out by utilizing universal 16S rDNA primer pair 16SF/16SR and pel gene primers Y1/Y2 (1). The 16S rDNA and pel gene sequences of isolate HNXDT002 (GenBank Accession Nos. JF721958 and JF721960, respectively) had 99 and 93% nucleotide identity with strains of P. carotovorum subsp. carotovorum (GenBank Accession Nos. U80197 and CP001657, respectively). Pathogenicity was confirmed by needle-stab inoculation (1 × 10⁸ CFU/ml) at the stem on three healthy artichoke plants held at 28°C for 48 h. Sterile distilled water was used as a negative control. Within 72 h after inoculation, water-soaking and soft-rot symptoms were observed on all inoculated artichoke plants, while controls remained healthy. The bacterium was recovered only from rotted stems of inoculated plants. In recent years, P. carotovorum was reported on such plants as Pinellia ternata (4) and Chinese cabbage (2) in China. To our knowledge, this is the first report of bacterial rot disease caused by P. carotovorum subsp. carotovorum on artichoke in China. References: (1) D. J. Brenner et al. Bergey's Manual of Systematic Bacteriology. Vol. 2. Springer, NY, 2005. (2)Y. Fang et al. Acta Microbiol. Sinica 44:136, 2004. (3) H. Yi-Bo et al. Acta Phytopathol. Sinica 37:338, 2007. (4) F. X. Ying et al. Plant Dis. 91:1359, 2007.

In vivo biocompatibility and degradation behavior of Mg alloy coated by calcium phosphate in a rabbit model

This study is conducted to investigate the biocompatibility and biodegradation behavior of calcium phosphate-coated Mg alloy in vivo. Calcium phosphate (Ca-P) was coated on the Mg alloy (AZ31) by a chemical process. Samples of Ca-P coated rods, the naked alloy rods, and degradable polymer as controls were implanted into the thighbone of rabbits to investigate the bone response at the early stage. The reduction in implant volume was determined by micro-computed tomography and three-dimensional reconstruction of the remaining Mg alloy segmented from the bone matrix. It was observed that the biodegradation rate of naked Mg implant is faster than that of the coated ones. The bone-implant interface was characterized in sections by scanning electron microscopy with energy-dispersive spectroscopy. Biodegradation or reaction layer was formed on the surface of Mg alloy implants and direct contact with the surrounding bone. The layer was mainly composed of Ca, P, O, and Mg. After 8 weeks of post-operation, paraffin sections were generated for histomorphologic analysis; 100% implants were fixed and no inflammation was observed. Histological analysis showed that new bone tissue is formed around the Mg implants, and no fibrous capsule was found. Blood examination showed that the biodegradation of the Mg implant caused little change to blood composition. Ca-P coating on Mg alloy substrate might be an effective method to reduce the biodegradation rate of Mg alloy in vivo and improve the surface bioactivity of Mg alloy implants.

Gasless Laparoscopy versus Conventional Laparoscopy in Uterine Myomectomy: A Single-Centre Randomized Trial

In a single-centre, randomized trial, gasless laparoscopic myomectomy was compared with conventional laparoscopic myomectomy. The study examined feasibility, safety, reliability and post-operative outcomes. Estimated blood loss, duration of surgery, early post-operative outcomes and length of hospital stay were recorded. Compared with conventional laparoscopic myomectomy, gasless laparoscopy resulted in significantly lower intra-operative blood loss (median 100 ml vs 80 ml, respectively) and duration of surgery (median 94 min vs 71 min, respectively). Post-operative abdominal drainage volume was significantly lower after gasless laparoscopy than after conventional laparoscopy (median 100 ml vs 240 ml). There was no significant difference between duration of post-operative fever, post-operative time to flatus or length of hospital stay. Both forms of laparoscopy are suitable for uterine myomectomy, and comparison of these methods showed that gasless laparoscopy had potential advantages over conventional laparoscopy.

First Report of Anthracnose Caused by Glomerella acutata on Chili Pepper in China

A new anthracnose disease on chili pepper (cayenne pepper cv. Hongxiu 2003, fruiting type pepper) was found in Zhijiang County, Hunan, China in 2009. The disease was observed only on the fruits. Lesions were generally elongated, on which dark acervuli were arranged concentrically. Later, cracking of older lesions was observed. With a microscope, fungal conidia were observed to be 15.8 × 4.1 μm, fusiform or oval with one end acute, and single celled with two to seven oil globules. No setae were found on the acervuli. Eight isolates (HNZJ001-HNZJ008) showed no difference in colony feature when cultured on potato dextrose agar. All the isolates showed white growth at the early stages, but colonies turned pink when they produced powdery spores and then finally became red gray. The average colony diameter was 68.5 to 72.3 mm after 7 days with obvious gray black concentric rings because of the development of aerial and substrate mycelia. After a needle-prick inoculation with a suspension of 1 × 10⁶ spores per ml of HNZJ001 on 30 chili pepper fruits with three repeats, the same symptoms were observed and the same fungus was recovered. In bioassays, HNZJ001 caused lesions on both mature and immature fruits, while Glomerella cingulata strain LSQ1 (GenBank Accession No. HQ607386) used as a control did not infect immature fruits. PCR amplification was carried out by utilizing universal rDNA-ITS primer pair ITS4/ITS5. Sequencing of the PCR products of HNZJ001 (GenBank Accession No. GU059863) showed 100% identity to G. acutata (GenBank Accession No. EU008863) and Colletotrichum acutatum (GenBank Accession No. AF207794) after a BLAST search. The pathogen was identified as G. acutata (asexual stage: C. acutatum) on the basis of morphological characters and rDNA-ITS sequence analysis. Worldwide, it has been reported that pepper anthracnose might be caused by up to five species of Glomerella (Colletotrichum): G. cingulata, C. coccodes, C. capsici, C. dematium, and G. acutata (2), among which only the first three were previously reported in China. In recent years, G. acutata was reported on such plants as apple (3) and strawberry (1) in China, but not on pepper. To our knowledge, this is the first report of G. acutata on chili pepper in China. References: (1) X.-J. Ren et al. Acta Phytopathol. Sin. 38:325, 2008. (2) P. P. Than et al. Zhejiang Univ. Sci. B 9:764, 2008. (3) R. Zhang et al. Plant Dis. 92:1474, 2008.

Fitness effects of derived deleterious mutations in four closely related wild tomato species with spatial structure

A key issue in evolutionary biology is an improved understanding of the genetic mechanisms by which species adapt to various environments. Using DNA sequence data, it is possible to quantify the number of adaptive and deleterious mutations, and the distribution of fitness effects of new mutations (its mean and variance) by simultaneously taking into account the demography of a given species. We investigated how selection functions at eight housekeeping genes of four closely related, outcrossing species of wild tomatoes that are native to diverse environments in western South America (Solanum arcanum, S. chilense, S. habrochaites and S. peruvianum). We found little evidence for adaptive mutations but pervasive evidence for strong purifying selection in coding regions of the four species. In contrast, the strength of purifying selection seems to vary among the four species in non-coding (NC) regions (introns). Using F(ST)-based measures of fixation in subdivided populations, we suggest that weak purifying selection has affected the NC regions of S. habrochaites, S. chilense and S. peruvianum. In contrast, NC regions in S. arcanum show a distribution of fitness effects with mutations being either nearly neutral or very strongly deleterious. These results suggest that closely related species with similar genetic backgrounds but experiencing contrasting environments differ in the variance of deleterious fitness effects.

Turbulence decay rate as a measure of flow dimensionality

The dimensionality of turbulence in fluid layers determines their properties. We study electromagnetically driven flows in finite-depth fluid layers and show that eddy viscosity, which appears as a result of three-dimensional motions, leads to increased bottom damping. The anomaly coefficient, which characterizes the deviation of damping from the one derived using a quasi-two-dimensional model, can be used as a measure of the flow dimensionality. Experiments in turbulent layers show that when the anomaly coefficient becomes high, the turbulent inverse energy cascade is suppressed. In the opposite limit turbulence can self-organize into a coherent flow.

Preparation of high surface area activated carbon from coconut shells using microwave heating

The present study attempts to utilize coconut shell to prepare activated carbon using agents such as steam, CO(2) and a mixture of steam-CO(2) with microwave heating. Experimental results show that the BET surface area of activated carbons irrespective of the activation agent resulted in surface area in excess of 2000 m(2)/g. The activation time using microwave heating is very much shorter, while the yield of the activated carbon compares well with the conventional heating methods. The activated carbon prepared using CO(2) activation has the largest BET surface area, however the activation time is approximately 2.5 times higher than the activation using steam or mixture of steam-CO(2). The chemical structure of activated carbons examined using Fourier transformed infra-red spectra (FTIR) did not show any variation in the surface functional groups of the activated carbon prepared using different activation agents.

Primary oral leiomyosarcoma: a retrospective clinical analysis of 20 cases

PURPOSE

As a review and clinical analysis of primary oral leiomyosarcoma (LMS) cases in West China stomatology Hospital in the past 37 years, this study provides demographic, therapeutic and prognostic information of this rare tumor.

PATIENTS AND METHODS

In our study, 20 cases of primary oral LMS treated between 1972 and 2008 in West China Stomatology Hospital were analyzed retrospectively. A thorough review of clinical records was carried out and potential indicators of survival were analyzed.

RESULTS

The most common symptom of oral LMS presented as a painless mass. The median age of patients was 37 years, and the peak incidence age of this tumor was in the 2nd and 5th decades. There was no predilection of gender, and the male-to-female ratio was 11:9. The most frequently occurring site of oral leiomysarcoma was the jawbones. The prognosis of this tumor was poor as a result of the high local recurrence and the estimated 2 year survival was 17.6%. The bony involvement and method of therapy was observed to have an influence on the prognosis and survival of this tumor (P < 0.05).

CONCLUSION

There was a predilection site of jawbones for oral LMS, and bony involvement was a potential indicator suggesting a poorer prognosis. The recommended method of therapy on this tumor was aggressive, radical surgical resection; however, adjuvant radiotherapy and chemotherapy may also have a beneficial effect.

Synthesis, antitumor evaluation and crystal structure of hydroxyurea derivatives

A series of hydroxyurea derivatives have been synthesized and elucidated by means of FT-IR, (1)H-, (13)C-NMR and MS. The exact stereostructures of representative compounds have been determined by X-ray crystal structure analysis. In the crystals, inversion dimers linked by pairs of N-H...O hydrogen bonds occurred, and further N-H...O links led to chains of molecules. In vitro antitumor activities against Tca8113 human tongue cancer cells and L1210 murine leukemia cells were evaluated. A total of 8 of the 12 compounds had higher inhibitory activities than hydroxyurea against L1210 cells. Among them, the most promising compounds were 3e, 3d, 3a and 2d.

Capillary rogue waves

We report the first observation of extreme wave events (rogue waves) in parametrically driven capillary waves. Rogue waves are observed above a certain threshold in forcing. Above this threshold, frequency spectra broaden and develop exponential tails. For the first time we present evidence of strong four-wave coupling in nonlinear waves (high tricoherence), which points to modulation instability as the main mechanism in rogue waves. The generation of rogue waves is identified as the onset of a distinct tail in the probability density function of the wave heights. Their probability is higher than expected from the measured wave background.

Sodium butyrate induces human colon carcinoma HT-29 cell apoptosis through a mitochondrial pathway

Some tumours respond favourably to tumour necrosis factor-alpha (TNF-alpha). Despite this preferential sensitivity, resistance to TNF-alpha remains a clinical problem and more interest is now being focused on finding compounds that induce apoptosis through other pathways. Sodium butyrate (NaBt) has anti-tumour effects on colon cancer cells, inhibiting cell growth and promoting differentiation and apoptosis. In this study we investigated whether NaBt induced apoptosis in the human colon cancer cell line HT-29 and examined the intracellular mechanisms involved. Pre-incubation of cells with NaBt significantly increased apoptosis as measured by fluorescence activated cell sorter analysis and mitochondrial membrane potential determination. This effect could be blocked with the caspase inhibitors, z-VAD-fmk (pan-caspase inhibitor), z-DEVD-fmk (caspase-3 inhibitor) and z-LEHD-fmk (caspase-9 inhibitor), but not with z-IETD-fmk (caspase-8 inhibitor). Enhancement of caspase-3 and caspase-9 activities suggests that NaBt induces apoptosis via mitochondrial pathways not involving TNF-alpha.

Phase randomization of three-wave interactions in capillary waves

We present new experimental results on the transition from coherent-phase to random-phase three-wave interactions in capillary waves under parametric excitation. Above the excitation threshold, coherent wave harmonics spectrally broaden. An increase in the pumping amplitude increases spectral widths of wave harmonics and eventually causes a strong decrease in the degree of the three-wave phase coupling. The results point to the modulation instability of capillary waves, which leads to breaking of continuous waves into ensembles of short-lived wavelets or envelope solitons, as the reason for the phase randomization of three-wave interactions.

Facile Synthesis of Novel Nanostructured MnO(2) Thin Films and Their Application in Supercapacitors

Nanostructured alpha-MnO(2) thin films with different morphologies are grown on the platinum substrates by a facile solution method without any assistance of template or surfactant. Microstructural characterization reveals that morphology evolution from dandelion-like spheres to nanoflakes of the as-grown MnO(2) is controlled by synthesis temperature. The capacitive behavior of the MnO(2) thin films with different morphologies are studied by cyclic voltammetry. The alpha-MnO(2) thin films composed of dandelion-like spheres exhibit high specific capacitance, good rate capability, and excellent long-term cycling stability.

Preparation of activated carbon from coconut shell chars in pilot-scale microwave heating equipment at 60 kW

Experiments to prepare activated carbon by microwave heating indicated that microwave energy can decrease reaction temperature, save the energy and shorten processing time remarkably compared to conventional heating, owing to its internal and volumetric heating effects. The above results were based on the laboratory-scale experiments. It is desirable to develop a pilot-scale microwave heating equipment and investigate the parameters with the aim of technological industrialization. In the present study, the components and features of the self-invented equipment were introduced. The temperature rise curves of the chars were obtained. Iodine numbers of the activated carbons all exceed the state standard of China under the following conditions: 25 kg/h charging rate, 0.42 rev/min turning rate of ceramic tube, flow rate of steam at pressure of 0.01 MPa and 40 kW microwave heating power after 60 kW pre-activation for 30 min. Pore structure of the sample obtained at a time point of 46 h, which contained BET surface area, and pore size distributions of micropores and total pores, was tested by nitrogen adsorption at 77K.

Di-μ-chlorido-bis-{bis-[3,5-dimethyl-pyrazol-1-yl-κN)methane]iron(II)} bis-[tetra-chloridoferrate(III)]

In the title complex, [Fe₂Cl₂(C₁₁H₁₆N₄)₄][FeCl₄]₂, the asymmetric unit is composed of one and a half units of [Fe(bdmpm)₂Cl]₂(FeCl₄)₂(bdmpm = bis(bis(3,5-dimethyl­pyrazol-1-yl)methane). The three independent Fe^II atom have a distorted octa­hedral coordination geometry comprising two bridging chloride anions and four N atoms from two bis­(3,5-dimethyl­pyrazol-1-yl)methane ligands. The Fe^III atom has a tetra­hedral coordination geometry comprising four chloride anions.

Turbulence-condensate interaction in two dimensions

We present experimental results on turbulence generated in thin fluid layers in the presence of a large-scale coherent flow, or a spectral condensate. It is shown that the condensate modifies the third-order velocity moment in a much wider interval of scales than the second one. The modification may include the change of sign of the third moment in the inverse cascade. This observation may help resolve a controversy on the energy flux in mesoscale atmospheric turbulence (10-500 km): to recover a correct energy flux from the third velocity moment one needs first to subtract the coherent flow. We find that the condensate also increases the velocity flatness.