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Given their hovering ability, static lift airships, such as airships and balloons, are proposed as stratospheric platforms flying at a high altitude of 20 km. The shape of the envelope has a major influence on the lift and drag efficiency of an airship. Furthermore, the efficiency of a conventional actuator, such as an aerodynamic control surface for stratospheric platforms, is decreased by the low-atmospheric density and flight speed. Thus, a new type of effector configuration must be proposed. A new multivectored thrust airship called flat peach is proposed in this paper. The name is attributed to the shape of the airship, which resembles a flat peach that is a cross between a ball and a water droplet. Thus, this airship has a smaller drag coefficient than the spherical airship and higher lift efficiency than a conventional airship. A control allocation strategy among the multivectored thrusters is proposed, and a composite control structure is designed for the airship to realize accurate position control and to decrease energy consumption.

The nonlinear dynamics model is established by using Newton - Euler method, and the action of wind on the airship is taken into consideration. The effect of wind on the dynamics of the airship is investigated, including the influence of steady wind on the flight trajectory, and the wind shear on the dynamic response of the airship. The optimal ascending trajectory is designed to perceive the anti-wind ability of the airship. One active anti-wind guidance strategy is proposed to achieve accurately trajectory tracking. The results show that: the primary effects of the wind on the airship include the variation of dynamic pressure and the external forces generated from the wind movement. The steady wind have a great impact on the ascending and descending trajectories, and the vertical wind shear will effects the attitude response of airship. The optimal trajectories in ascending and descending can be generated by using numerical optimal methods under various wind fields. The proposed active anti-wind guidance strategy can perform more accurately trajectory tracking under the measured wind field.

The functions of the distal colon are regulated by local and extrinsic neural pathways. In previous studies, we have found that dopamine (DA) and norepinephrine (NE) could evoke colonic ion transport by activating β-adrenoceptors. The present study aims to investigate the segmental differences in expression and activation of β-adrenoceptors in the distal colon in physiological and pathophysiological conditions.Real-time PCR, immunofluorescence, and Western blotting were used to detect the expression of β-adrenoceptors in the rat and human distal colon. Short-circuit current measurements (Isc) were used to assess the role of β-adrenoceptors in ion transport.DA and NE caused greater suppression of baseline Isc in distal colon adjacent to the rectum than in segments further away from the anus. These responses were inhibited by selective antagonists of β₁- and β₂-adrenoceptors, but not β₃-adrenoceptor. The expression levels of β₁- and β₂-adrenoceptors in colonic mucosa were higher in colorectum than the regions away from the anus of rats and humans. In wrap-restraint stress (2 h), DA-, NE-induced ΔIsc and the expression of β-adrenoceptors in the colorectum were significantly reduced. However, when endogenous catecholamines were depleted by 6-hydroxydopamine (75 mg kg(-1), i.p., 3 days), DA-, NE-induced ΔIsc as well as the expression of β-adrenoceptors were significantly enhanced in the rat colorectum but not in more proximal regions of the distal colon.β₁- and β₂-adrenoceptors are predominantly expressed in the colorectal mucosa. Perturbation of endogenous catecholamine levels influences the expression and activation of β-adrenoceptors in the colorectal region.