Search

Maximum ellipsoidal magnitude of the droplet is an important basic parameter for calculating drag force, droplets axial-velocity and dispersed-phase pressure gradient in an annular-mist pipe flow. An analytical correlation to predict the maximum ellipsoidal magnitude of a low-viscosity droplet in a parallel gas stream based on energy conservation and volume conservation. Stagnant pressure distribution on droplet surface is revised from Flachsbart's formula. The proposed correlation has clear physical meaning and easy to use. The correlation captures the deformation mechanism with an average absolute percent error of 9.53%. The effect of stagnant pressure distribution on the proposed correlation's accuracy is discussed.

Somatic embryogenesis receptor-like kinase (SERK) is a small gene family found in plants. SERK is involved in somatic embryogenesis and can be found in various important signal transduction pathways. Research on SERK found in pineapple (AcSERK1 and AcSERK2) has indicated that these genes could be used as potential marker genes for monitoring the acquisition of embryogenic competence. This experiment was designed to study somatic embryogenesis in pineapple in detail using AcSERK1 as a marker gene. The results showed that somatic embryogenesis in pineapple callus originated from the surface, the inside, and the superficial layer of the callus. Very few parenchyma cells could be converted into competent cells under 2,4-D induction. The competent cells passed through the pro-embryo-protuberance, the pro-embryo, and the early stage globular embryo. The passage of competent cells through these channels formed the globular embryo. AcSERK1 expression was upregulated by jasmonic acid (JA), salicylic acid (SA), injury, and low temperature treatment. The His6-AcSERK1 protein had autophosphorylation activity. These results confirmed that AcSERK1 can be used as a marker gene for the study of embryogenesis and for expression of totipotency in pineapple. The results indicated that AcSERK1 may also play a role in pineapple stress-response signaling. For future studies, the prokaryotically-expressed His6-AcSERK1 protein can be used to examine the receptor-like kinases function of SERK proteins.

Background Cannabis and tobacco have contrasting cognitive effects. Smoking cannabis with tobacco is prevalent in many countries and although this may well influence cognitive and mental health outcomes, the possibility has rarely been investigated in human experimental psychopharmacological research. Method The individual and interactive effects of cannabis and tobacco were evaluated in 24 non-dependent cannabis and tobacco smokers in a randomized, placebo-controlled, double-blind, 2 (cannabis, placebo) × 2 (tobacco, placebo) crossover design. Verbal memory (prose recall), working memory (WM) performance including maintenance, manipulation and attention (N-back), psychotomimetic, subjective and cardiovascular measures were recorded on each of four sessions. Results Cannabis alone impaired verbal memory. A priori contrasts indicated that tobacco offset the effects of cannabis on delayed recall. However, this was not supported by linear mixed model analysis. Cannabis load-dependently impaired WM. By contrast, tobacco improved WM across all load levels. The acute psychotomimetic effects and ratings of ‘stoned’ and ‘dizzy’ induced by cannabis were not altered by tobacco. Cannabis and tobacco had independent effects on increasing heart rate and interacting effects on increasing diastolic blood pressure. Conclusions Relative to placebo, acute cannabis impaired verbal memory and WM. Tobacco enhanced performance on WM, independently of cannabis. Moreover, we found some preliminary evidence that tobacco may offset the effects of cannabis on delayed, but not immediate, verbal recall. In contrast, the psychotomimetic and subjective effects of cannabis were unaffected by tobacco co-administration. By reducing the cognitive impairment from cannabis, tobacco co-administration may perpetuate use despite adverse health consequences.

Calculation of the hydraulic gradient due to the upward flow of a large size particles.water mixture in a swaying vertical pipe is a central problem in the design of systems for deep-sea mining of manganese modules. Here, the problem is investigated experimentally and with a mathematical model. An experimental apparatus that mimics the deep-sea mining system was built to investigate the effects of swaying on the hydraulic gradient. The experimental results reveal that the hydraulic gradient in a swaying vertical pipe is greater than in a fixed vertical pipe (for the same flow and solid-loading conditions) as a result of the instantaneous particle-wall collisions and the solids sliding over the pipe wall. A mathematical model for the mixture flows is suggested based on a Lagrangian simulation technique. The model results offer additional insight into the dynamics of this complex flow and agree well with the new laboratory data.

The calculation of the hydraulic gradient due to the upward flow of a large size particles—water mixture in a vertical pipe is a central problem in the design of systems for deep-sea mining of manganese nodules. Here, the problem is investigated experimentally and with a new calculation method. An experimental apparatus that mimics the deep-sea mining system was built to measure the hydraulic gradient due to the mixture upward flow, the settling velocity of a single manganese nodule, and to explore the relationship between the concentration of fluidized manganese nodules and the solid slip velocity. Experimental relations are found. Also, a formula to compute the total hydraulic gradient of the mixture flow under different flow and solid-loading conditions is developed; the formula accounts for the hydraulic gradients produced by the liquid phase, the solid phase, and the inter-particle collisions. The predictions obtained with the derived equation are compared with experimental data readily available and with the newly acquired laboratory data; these predictions agree very well with the empirical data and demonstrate the value of the model as a design tool.@DOI: 10.1115/1.1641385#

Psoriasis is a chronic inflammatory skin disease characterized by excessive proliferation of keratinocytes. Fibroblast growth factor 10 (FGF10) acts as a growth factor for keratinocyte proliferation. The aim of this study is to investigate whether FGF10 blockage, a new monoclonal antibody against FGF10 we generated, could mitigate topical propranolol-induced psoriasis-like lesions in guinea pigs.The monoclonal anti-FGF10 was generated by a routine method and purified by affinity chromatography. The effect of FGF10 and anti-FGF10 on human keratinocyte HaCaT cell proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The back of the ears of individual guinea pigs was topically exposed to 5% propranolol emulsion to induce psoriasis-like lesions and randomly treated topically with phosphate buffered saline (PBS), hydrocortisone butyrate, or different doses of anti-FGF10. The pathologic changes and the degrees of inflammation in the auricular areas of individual animals were examined histologically.Characterization revealed that anti-FGF10 had a purity of 90% and a titer of 1:12800. We found that FGF10 stimulated HaCaT cell proliferation while treatment with different doses of anti-FGF10 inhibited FGF10-induced cell proliferation in a dose-dependent manner (100, 200 ng/ml, p0.05 vs. control; 400, 800, 1600 ng/ml, p0.01 vs. control). Compared to PBS-treated psoriatic animals, treatment with anti-FGF10, like hydrocortisone butyrate, greatly inhibited the severity of psoriasis-like lesions by reducing the Baker's scores, the thickness of epidermis, and the numbers of monocyte infiltrates in the dermis of animals.The newly generated anti-FGF10 monoclonal antibody inhibited the proliferation of human keratinocytes in vitro and mitigated inflammation and pathogenic changes in propranolol-induced psoriasis-like lesions in animals. Therefore, these findings may provide a proof of principle that blockage of FGF-10 may inhibit psoriasis-related inflammation.

Four pairs of paddocks of prairie grass (Bromus willdenowii Kunth cv. Grasslands Matua) and white clover (Trifolium repens L. cv. Grasslands Pitau) were grazed by lactating cows 3 times in rotation between September 1988 and February 1989 to residuals of either 6 cm height and 1.5–2.5 t DM/ha residual mass (hard grazing, Treatment H) or 12 cm height and 2.5–3.51 DM/ha (lax grazing, Treatment L). Detailed measurements were made of the effects of grazing management and season upon plant and tiller populations, and upon prairie grass plant tissue dynamics. Treatment H reduced the leaf appearance interval by 35% and the number of live leaves per tiller by 17%, compared with Treatment L. Leaf weight and total dry weight per tiller were also substantially reduced by hard grazing, though the reductions were greater after the first (39 and 53%) and second grazings (53 and 74%) than after the third grazing (22 and 22%). Hard grazing reduced tiller numbers per plant and per unit area by 22 and 37% respecti...

Simultaneous measurements of magnetic susceptibility from 0.5 to 10 mK and pressure from 2.88 to 3.54 MPa have been made in 3He nanoclusters embedded in a 4He matrix, following phase separation. The susceptibility of the 3.54 MPa, all –solid sample behaves similarly to that of bulk 3He for v = 21.3 cm3/mole, with a Weiss constant θ = -250μK. For the 2.88 MPa, liquid-droplet sample, θ = 140μK, indicating a ferromagnetic tendency, similar to 2-D films at some coverages. At intermediate pressures, χ has a peak near 1.05 mK, but without a discontinuity. For all samples, χ had a solid-like contribution to the lowest temperatures. Magnetic ordering in nano-clusters appears to be different than the U2D2 phase of bulk 3He.

Plots of perennial ryegrass were grazed by sheep at 3 to 4-week intervals under hard (postgrazing herbage mass 1000 kg DM/ha) and lax (2000 kg DM/ha) management from October 1986 to August 1988. In early December 1987 treatments on half the plots were switched, giving 4 combinations of hard and lax grazing with 4 replicates. Tiller populations were consistently higher under hard than lax grazing. Net pasture and leaf production rates were also generally higher under hard grazing, because higher senescence losses compensated for higher rates of pasture growth under lax grazing. The switch from hard to lax grazing in late spring gave a transient increase in net pasture production, but the switch from lax to hard grazing at the same time resulted in a high tiller appearance and enhanced net leaf production over the summer. Management strategies to take advantage of this latter effect in pasture systems are discussed briefly. Keywords Tiller population, tissue turnover, grazing management, perennial ryegrass