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.

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.

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...

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