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1.
We demonstrate universal computation in an all-fluidic two-phase microfluidic system. Nonlinearity is introduced into an otherwise linear, reversible, low-Reynolds number flow via bubble-to-bubble hydrodynamic interactions. A bubble traveling in a channel represents a bit, providing us with the capability to simultaneously transport materials and perform logical control operations. We demonstrate bubble logic AND/OR/NOT gates, a toggle flip-flop, a ripple counter, timing restoration, a ring oscillator, and an electro-bubble modulator. These show the nonlinearity, gain, bistability, synchronization, cascadability, feedback, and programmability required for scalable universal computation. With increasing complexity in large-scale microfluidic processors, bubble logic provides an on-chip process control mechanism integrating chemistry and computation. 相似文献
2.
Abstract – Video cameras inside underwater housings were used to record the spawning behaviour of a subspecies of the white‐spotted charr, the amemasu charr (Salvelinus leucomaenis leucomaenis) in the Tokimae and Onbetsu Rivers, Hokkaido, Japan. Unlike other Salvelinus species, in which females use lateral swings of their bodies to ventilate and distribute eggs over gravel crevices (undulating) immediately after spawning, female amemasu charr covered their eggs with beats of their tails (cover digging). Cover digging right after spawning has previously been documented in Salmo, Oncorhynchus and Parahucho. Phylogenetic analysis of postspawning behaviours in the Salmoninae indicated that (i) resting then covering the eggs is plesiomorphic for the group, (ii) undulating replaced resting in the ancestor of Salvelinus, (iii) cover digging was advanced in the behavioural sequence to occur immediately after egg deposition in the ancestor of Parahucho + Salmo + Oncorhynchus and in the amemasu. 相似文献
3.
Vyas S Sharma M Sharma PD Singh TV 《Journal of agricultural and food chemistry》2007,55(15):6319-6324
The partially purified catechin fraction isolated from green tea extract was treated with a variety of acylating agents (acyl anhydrides/chloride) to obtain (-)-epigallocatechin-3-gallate (EGCG) O-acyl derivatives in 20-25.4% yields. The (-)-EGCG O-acyl derivatives were characterized by physical data and spectral studies. These compounds were evaluated for their antitumor activity by use of a two-stage carcinogenesis model in 7,12-dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol 13-acetate (TPA)--induced cancer in Swiss albino mice. The study showed that there was a significant decrease in the antitumor activity with the increase in size and branching of the chain length of acyl groups. The results indicated that these O-acyl derivatives of (-)-EGCG have the potential to be developed as cancer chemopreventive agents. Keywords: Green tea; catechins; (-)-EGCG O-acyl derivatives; antitumor activity. 相似文献
4.
Hayford Manu Suhyup Lee Mike C Keyes Jim Cairns Samuel K Baidoo 《Journal of animal science》2021,99(5)
We investigated the effect of feeding time on behavior and stress responses in pregnant sows under isocaloric conditions. Twenty-four sows were balanced for parity and randomly assigned to 1 of 3 feeding times. Corn–soybean meal-based diet was fed once at: 0730 (Control, T1), 1130 (T2), and 1530 hours (T3). On average, sows received 7,062 kcal ME/d from 2.20 kg of diet formulated to contain SID Lys/ME of 1.71 g/Mcal. The study was conducted for 28 d (21 d acclimation to the feeding regime and 7 d data collection). Saliva samples were collected every 2 hr for 12 hr in stalls on day 52 of pregnancy. Behavior data were collected 24 hr for 7 d from day 53 of gestating by affixing a remote insights ear tag to each sow. Each sow had 120,960 data points categorized into: “Active,” “Feed,” or “Dormant”. Due to housing constraint, all sows were housed in individual stalls in the same barn presenting a potential limitation of the study. Data were analyzed using PROC MIXED and GLIMMIX procedures of SAS 9.4 for cortisol and behavior data, respectively. Sow was the experimental unit. The area under the curve (AUC) is quantitative evaluation of response as threshold varies over all possible values. A 12-hr cortisol total AUC for sows fed once daily at 1130 hours was reduced relative to sow group fed at 1530 hours (P = 0.046) but similar compared with the control sows (P = 0. 323). The control sows (0730 hours) had reduced total (P < 0.001) and feeding (P = 0.001) activity AUCs relative to sows on 1130 hours but did not differ compared with sows on 1530 hours feeding schedules (P > 0.100). Sows on 1130 hours feeding schedule had greater feed anticipatory activity, 24-hr total activity count, total (P < 0.001) and feeding (P < 0.001) activity AUC compared with sows fed daily at 1530 hours. In conclusion, feeding pregnant sows earlier in the morning (0730 hours) appears to minimize sows’ behavior but similar cortisol response. Sows on 1130 hours feeding schedule had greater activities but reduced cortisol concentration, suggesting that elevated sow activity might not necessarily indicate activation of hypothalamic–pituitary–adrenal axis. 相似文献
5.
Ajay Kumar Dang Manu Jamwal Mandheer Kaur Shiv Prasad Kimothi Shashi Pal Kalyan De Mohsin M. Pathan Dilip K. Swain Sushil K. Mohapatra Suman Kapila Rajeev Kapila Harjit Kaur Ashok K. Mohanty Bukkaraya S. Prakash 《Tropical animal health and production》2013,45(4):1047-1050
Micronutrients when fed around peripartum may reduce the stress induced by cortisol. With this objective, 24 Sahiwal (SW) and 24 Karan Fries (KF) cows and 24 Murrah (Mu) buffaloes were taken and divided into four groups of six each. Vitamin E (VE), zinc (Zn) and copper were supplemented from 30 days pre- to 30 days postcalving in groups 1, 2 and 3. Animals without supplementation served as control. Blood sampling was done on days 30, 15, 7 and 3 precalving; at calving; and on days 3, 7, 15 and 30 postcalving. Plasma cortisol levels were measured by ELISA. Supplementation of VE and Zn significantly (P?<?0.05) reduced plasma cortisol levels at calving and at 30 days postcalving. KF cows exhibited best results with VE, whereas SW cows and Mu buffaloes responded best to Zn. Copper increased the peripartum cortisol levels. Reduction in cortisol levels may help in keeping the animal healthy and stronger to fight immuno-suppression generally observed around the period of peripartum. 相似文献
6.
Tan JY Valberg SJ Sebastian MM Davis GD Kelly JR Goehring LS Harland MM Kuebelbeck KL Waldridge BM Newton JC Reimer JM 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(9):993-999
Five horses were presented with signs of myopathy along with systemic malaise, hyperfibrinogenemia, hyperphosphatemia, and an elevated calcium phosphorus product (Ca*P). Postmortem findings were consistent with systemic calcinosis, a syndrome of calcium deposition in the tissue of organs including lungs, kidneys, muscle, and heart that has not been previously described in horses. 相似文献
7.
Intercropping millet with cowpea is a widespread practice throughout the semi‐arid regions of West Africa. Low soil phosphorus (P) is one of the main limiting factors for crop production in this region. The objective of this study was to determine optimum methods and rates of P application to a millet/cowpea intercrop on a sandy, dunal soil of western Niger. Triple super phosphate was applied by three different methods: broadcast, in millet hills, and in cowpea hills. Three rates (0, 22.5, and 45.0 kg P/ha) were applied by each method. Treatments were replicated four times in a randomized complete block design. Cowpea yields were not affected by P applications, but millet yields were maximum with 45.0 kg P/ha applied to the millet hills. The 45.0 kg P/ha broadcast and millet hill applications resulted in significantly higher leaf P levels for millet, but no significant differences were found in cowpea leaf P levels. The 45.0 kg P/ha treatment applied to millet hills also resulted in the maximum P uptake, greatest biomass production, and highest economic yield. However, P use efficiency was higher in the treatment with 22.5 kg P/ha applied to the millet hills. Phosphorus management systems must be developed which optimize yield and economic return, as well as nutrient and water use efficiencies. 相似文献
8.
Maintenance of soil carbon stocks is vital for the environment at large and for maintenance of soil chemical, physical and biological fertility. Tonga represents a country in agricultural transition from subsistence to commercial production and whilst this is good for the national economy the impact on soil resources is less clear. The major cropped soils, fallow vegetation types and forest systems of Tonga were identified in each island group and samples of representative soils (0.15 m depth) from each land use unit were taken. Total carbon (CT) and δ13C were measured and labile carbon (CL) determined by oxidation with 333 mm KMnO4. These data were used to determine the carbon management index (CMI) and the proportion of carbon from C4 species in the CT pool. Relative to primary forest, the soil CT and CL generally declined with changes in vegetation and more intense mechanical tillage. The contribution of C4 plants to soil C increased with intensity of mechanical tillage and the prevalence of C4 guinea grass (Panicum maximum Jacquin) fallow. The changes in soil C were reflected in the CMI, and CL was a more sensitive indicator of change than CT. These data indicates that all land use systems have experienced a large net loss of soil C relative to the forest systems. Soil mean weight diameter (MWD) decreased significantly with increased intensity of mechanical tillage and to a lesser extent with the intensity and length of cropping. The relationship between soil MWD and soil C was similar with soil CT and CL. Grass fallow was as effective as permanent vegetation systems in improving soil MWD and lowering the micro‐aggregate (<125 μm) fraction. 相似文献
9.
The variability of bird beak morphology reflects diverse foraging strategies. One such feeding mechanism in shorebirds involves surface tension-induced transport of prey in millimetric droplets: By repeatedly opening and closing its beak in a tweezering motion, the bird moves the drop from the tip of its beak to its mouth in a stepwise ratcheting fashion. We have analyzed the subtle physical mechanism responsible for drop transport and demonstrated experimentally that the beak geometry and the dynamics of tweezering may be tuned to optimize transport efficiency. We also highlight the critical dependence of the capillary ratchet on the beak's wetting properties, thus making clear the vulnerability of capillary feeders to surface pollutants. 相似文献
10.
V. K. Avornyo A. Manu R. Adu-Gyamfi 《Communications in Soil Science and Plant Analysis》2020,51(7):985-996
ABSTRACTSoybean yields in Ghana are low and stagnant in spite of the trio of recommendations: (1) improved seed, (2) rhizobium inoculant and (3) phosphorous fertilizer application being promoted by government to boost productivity. This study evaluates the response of soybean to Pro-soil biostimulant, triple super phosphate (TSP), and rhizobium inoculant in the interior savanna of Ghana. A treatment structure comprising two mainplot factors (biostimulant and conventional), and four subplots factors; TSP, inoculant, TSP+Inoculant and unamended control arranged in a split-plot design was used for this study. Apart from dry matter which increased by 42%, Pro-soil biostimulant as a stand-alone management practice did not significantly increase agronomic parameters measured in this study. Biostimulant did not have a significant effect on grain yield, nodule weight, nodule number, canopy diameter, and plant height. Application of TSP alone, and in combination with inoculant, significantly increased yield, plant dry matter, nodule weight, nodule number, and dry pod weight. Highest soybean yield was obtained from TSP + Inoculant treatment, averaging 3.6 t ha?1 compared to 1.8 t ha?1 for control. Biostimulant, TSP+Inoculant combination resulted in yields as high as 4 t ha?1. Overall, the results indicate that neither PS-Foundation biostimulant nor rhizobia inoculation can be used as stand-alone management practices to increase soybean yield. However, an integrated application of PS-Foundation biostimulant, TSP, and inoculant could double current soybean yields in Ghana. 相似文献