¿Does ingestion by birds affect Pyracantha atalantoides (Rosaceae) seed germination?

Birds play a fundamental role in many ecosystems because they spread a variety of fruits and seeds through endozoochory. Pyracantha are very attractive for birds, which have contributed to spread this species in natural ecosystems. However, dispersion only is effective if seeds can germinate after passage through of bird digestive tract. Our goal was to assess if birds affect the start, speed and germination rate of P. atalantoides. Germination was compared between seeds from fruit and seed from bird feces. The germination percentage was similar between fruit and feces seeds. However, the seeds pass through the digestive tract delay speed, start and rate of germination. Our results support the idea that the advantage of being consumed by birds may lie more in seed movement away from the parent plant than in any seed treatment itself.

Development of Mixed Vertical Axis Wind Turbine (MVAWT) for Low Wind Condition

Small-scaled renewable energy generation such as micro-hydro and domestic solar panel has become the recent trend of research in order to achieve sustainable energy generation and to eliminate the reliance of geographical selection and large farm area. As for the case of wind energy, a wind turbine that can operate at low wind condition are desirable. This paper presents a mixed design for Vertical Axis Wind Turbine comprises of Savonius and Darrieus rotors, being assembled together as a single rotor turbine. The mixed wind turbine model (MVAWT) was fabricated and tested in our lab as prove of concept. Experiments conducted on 5 MVAWT’s configurations and being compared to a standalone Darrieus turbine with +3 degree pitch angle, showed promising result in lowering the self-start speed of the Darrieus turbine. It was observed that all the positive pitch angle MVAWTs has started to rotate at lower wind speed (about 1.8 m/s) while the standalone Darrieus turbine was only started to rotate at wind speeds more than 3.0 m/s. However, the lower self-start were also being compensated by lower turbine rotational speed. With the low self-start speed in the MVAWT, it will enable the wind energy capture for a longer period of time at a low wind condition site. This development should lead to an interesting research on optimizing the mixture of Savonius and Darrieus turbine for a localized low wind speed conditions in the future.

Soft-Starting Method Analysis of Belt Conveyor

This paper introduces several methods of soft start of belt conveyor, Through the analysis of all kinds of soft start mode, the prospects of development of soft start device of belt conveyor, and through the comparison of several commonly used start speed curve, the reasonable start speed curve, pointed out the direction for the research of soft start device of belt conveyor.

Schedules of Reward Shift in the Double Runway

Eighty food deprived rats received 62 trials in a double runway. On Trials 1–30, reward in the first goal box (GB1) was either always two food pellets or always zero pellets. All subjects received two pellets in the second goal box (GB2). On Trials 31–62 subjects in each preshift group (GB1 reward or GB1 nonreward) were shifted to the opposite GB1 reward level on 0, 25, 50, 75 or 100% of occasions. GB2 reward remained unaltered in all cases. For subjects experiencing reward decrease, second runway (A2) run and goal speeds after nonreward were generally enhanced, both within-group and in comparison with never rewarded controls. No such effect was evident on A2 start speed, nor was there any evidence to suggest that A2 performance after decreased reward was a function of the schedule of decrease. Increased GB1 reward resulted in general within-group impairment of A2 start and run speeds, with no effect on A2 goal performance. However, comparisons of speeds after increased reward with those of always rewarded controls revealed no difference on A2 start or run but indicated impairment of A2 goal performance. With the 50% schedule of reward increase, A2 run speeds after nonreward (the training level) exceeded those of never rewarded controls. Results are discussed with reference to McHose's contrast account of double runway phenomena and Amsel's frustration theory.

Sucrose-Pellet Incentive Shifts in the Double Alley

4 groups of male albino rats were given 45 double runway trials under the following conditions: (a) nonreward in goal box (GB1) throughout, (b) nonreward in GB1 for 30 trials followed by an upshift to two 97-mg. sucrose pellets for 15 trials, (c) two 97-mg. sucrose pellets in GB1 throughout, or (d) two 97-mg. sucrose pellets for 30 trials followed by a GB1 downshift to nonreward for 15 trials. Sucrose incentive upshift produced a rapid runway one start speed increment, while the downshift in sucrose had little or no effect on this measure. Runway one run and goal measures and all measures of runway two performance seemed little affected by GB1 incentive magnitude, in that all groups converged toward a common asymptote.