This article presents a feasibility analysis to remotely estimate the geo-location of a femto-satellite only using two station-CubeSats and the communication link between the femto-satellite and each ...CubeSat. The presented approach combines the Time Difference Of Arrival (TDOA) and Angle Of Arrival (AOA) methods. We present the motivation, the envisioned solution together with the constraints for reaching it, and the best potential sensitivity of the location precision for different (1) deployment scenarios of the femto-satellite, (2) precisions in the location of the CubeSats, and (3) precisions in each CubeSat’s Attitude Determination and Control Systems (ADCS). We implemented a simulation tool to evaluate the average performance for different random scenarios in space. For the evaluated cases, we found that the Cramér-Rao Bound (CRB) for Gaussian noise over the small error region of the solution is highly dependent on the deployment direction, with differences in the location precision close to three orders of magnitude between the best and worst deployment directions. For the best deployment case, we also studied the best location estimation that might be achieved with the current Global Navigation Satellite System (GNSS) and ADCS commercially available for CubeSats. We found that the mean-square error (MSE) matrix of the proposed solution under the small error condition can attain the CRB for the simulated time, achieving a precision below 30 m when the femto-satellite is separated by around 800 m from the mother-CubeSat.
•Passive cases with strategies of solar control reduced insolation and energy demands.•A simple design with mixed strategies saved 76.57% while a complex design alone 66%.•The most suggested ...solutions are complex FSS and SDs but well-oriented and designed.•Optimal azimuth angle is crucial indicator for planning strategic designs placement.•Complex designs can be used for the integration of renewable solar cooling system.
Urban patterns without highly designed buildings increase the urban heat and energy demands. Solar control techniques encompass strategies that, if properly designed and applied, can decrease solar radiation and cooling demands. The aim of this research is to establish and recommend the most effective and balanced solutions to decrease insolation and increase energy savings while balancing daylighting and visibility. Four main classes were reviewed: façade self-shading, shading devices, window-to-wall-ratio and building orientation. The results showed that the cases with such passive strategies effectively lowered the insolation and achieved potential energy savings of 4.64% to 76.57%. The strategies selected for six cases were suitable for subtropical and temperate zones. The most recommended solutions were complex designs of façade self-shadings and shading devices; their strategic placements and accurate designs can further improve their performance. The optimal building orientation is essential for determining optimal façades for the strategic placement of both complex and simple designs. A worldwide guide of azimuth angles was calculated for 59 locations. The results show that 58.62% locations should apply complex designs to the east, 24.13% to the northeast, 12.06% to the west and 5.17% to the southeast orientations for solar protection. In tropical and subtropical zones, complex designs can be integrated with renewable technologies.
•Visitation rates on soybean flowers were negatively affected by distance to the forest.•Larger flower visitors were observed at longer distance from the forest.•Insect visits to soybean flowers ...improved their reproductive success.
Increasing evidence indicates that pollinator diversity and pollination services are highly threatened by the destruction and fragmentation of natural habitats and the intensification of agricultural landscapes. Here we analyze the bee visiting ensemble on soybean flowers and the effects of pollinator visits on soybean reproductive success, within a fragmented Chaco forest landscape embedded in a soybean matrix in central Argentina. We assessed visitation rates in relation to distance from the forest (5, 50 and 100m) compared soybean bee assemblages with those on wild flowers in the nearby forest fragments, and carried out an exclosure experiment in order to assess the contribution of insect visits to soybean reproductive success. We also analyzed the relationship between visitor body size and the distance from the forest to the visited flower. Five species belonging to two families of bees were observed visiting soybean flowers. The bee species observed on soybean were well represented in the forest, and Apis mellifera was the most abundant species, visiting soybean flowers at all studied distances from the forest. Instead, wild visitors displayed a turnover of species throughout those distances, with smaller species being restricted to the forest proximity and replaced by larger ones toward the interior of the crop. Total visitation rates were significantly and negatively affected by distance to the forest. All plant productivity variables measured in the exclosure experiments were significantly improved in exposed flowers, duplicating the values observed without pollinators. The present study offers preliminary evidence linking forest proximity to higher visitation rates and presence of wild pollinators on soybean flowers thus providing for the first time, evidence of the forest role as pollinator donor for the soybean crop. It also shows that pollinator activity matters for this crop, leading to increased soybean yield. Further research on this topic is necessary in order to provide informed guidelines to enhance soybean production while simultaneously promoting natural habitat conservation.
The relative effects of hydrodynamic, thermodynamic, and geochemical factors on the fate and transport of oil in the subsea are not well understood to date. This glaring lack of knowledge in deep-sea ...spill studies precludes the parameterization of blowout far-field models. Here we use observations from the Macondo blowout to evaluate the importance of input variables in a numerical model of oil transport and fate. We adapt a multi-hydrocarbon fraction module to oil dissolution and run sensitivity analyses under various parameterization scenarios. We find that the inclusion of oil droplet atomization, variable flow rates (VFR), high-pressure biodegradation (HPB), and vertical currents׳ velocities (VV) affects significantly the subsea oil mass distribution in the water column as well as the evolution of deep plumes. In particular, droplets up to 50μm are neutrally buoyant and moved by deep currents predominantly driven by the topography, while the depth of the deep plume is very sensitive to the VV of the hydrodynamic model. We find good agreement between CTD cast observations and modeled mean depth of the oil mass, whereby HPB provide increased accuracy of predictions with time. The model suggests that VFR and HPB are mechanisms for the persistence of the southwestern deep plume observed at 1100m by increasing the residence time of the oil in the water column. Modeled oil concentrations range from 5 to 500ppb and present the highest values in the western and deepest locations of the subsea plume, which corroborate with field observations. We hypothesize that a substantial amount of subsea oil mass might have interacted with the bottom of the Mississippi Canyon.
The sterile insect technique (SIT) is used for the management of tephritid fruit fly pests. The South American fruit fly, Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), is one potential ...pest to be targeted by means of SIT. The success of SIT depends, to a large extent, on the sexual performance of sterile males. Various approaches have been evaluated with the aim of improving their sexual performance. These include the exposure to plant‐derived compounds and/or the provision of protein sources in the adults' diet capable of stimulating male mating success. The present study aimed to determine whether exposure to volatiles of Citrus limon (L.) Burm. F. (Rutaceae) essential oil and limonene confers a mating advantage to A. fraterculus laboratory males fed two distinct dietary regimes when competing with wild males for wild females under field cage conditions. Dietary regimes were, one, with non‐hydrolysed brewer's yeast and sugar (1:3 ratio), and the other with brewer's yeast hydrolysate enzymatic and sugar (1:12 ratio). The effect was evaluated in four variables associated with mating success: number of copulas obtained, latency to mate, copula duration, and copula location. Exposure to volatiles did not affect the number of matings achieved, irrespective of the diet given to the males. When laboratory males were fed with brewer's yeast hydrolysate, the effect of volatile exposure was shown in latency to mate, copula duration, and copula location. When the laboratory males were fed with non‐hydrolysed brewer's yeast, the effect of volatile exposure was shown only in copula duration. Laboratory males fed brewer's yeast hydrolysate achieved the same number of matings as wild males, whereas laboratory males fed non‐hydrolysed brewer's yeast had lower performance.
We evaluated the mating competitiveness of Anastrepha fraterculus (Diptera: Tephritidae) males, exposed to plant volatiles under semi‐natural conditions and in competition with wild males for wild females, and fed one of two diets with different protein sources. We found an effect of exposure to volatiles on copula duration and mating location favouring exposed males. Also, we confirmed the relevance of protein intake as an adult, which encourages the incorporation of yeast derivatives, particularly brewer's yeast hydrolysate, into the pre‐release diet.
Purpose
This study aimed to perform a systematic review and meta-analysis comparing the efficacy and safety outcomes of robotic-assisted and laparoscopic techniques for incisional hernia repair.
...Methods
PubMed, Embase, Scopus, Cochrane databases, and conference abstracts were systematically searched for studies that directly compared robot-assisted versus laparoscopy for incisional hernia repair and reported safety or efficacy outcomes in a follow-up of ≥ 1 month. The primary endpoints of interest were postoperative complications and the length of hospital stay.
Results
The search strategy yielded 2104 results, of which four studies met the inclusion criteria. The studies included 1293 patients with incisional hernia repairs, 440 (34%) of whom underwent robot-assisted repair. Study follow-up ranged from 1 to 24 months. There was no significant difference between groups in the incidence of postoperative complications (OR 0.65; 95% CI 0.35–1.21;
p
= 0.17). The recurrence rate of incisional hernias (OR 0.34; 95% CI 0.05–2.29;
p
= 0.27) was also similar between robotic and laparoscopic surgeries. Hospital length of stay (MD − 1.05 days; 95% CI − 2.06, − 0.04;
p
= 0.04) was significantly reduced in the robotic-assisted repair. However, the robot-assisted repair had a significantly longer operative time (MD 69.6 min; 95% CI 59.0–80.1;
p
< 0.001).
Conclusion
The robotic approach for incisional hernia repair was associated with no significant difference between the two groups in complications and recurrence rates, a longer operative time than laparoscopic repair, but with a shorter length of stay.
Galling insects tend to be highly sensitive to changes in their host plants or their environment. Here we analyze the effects of Chaco Serrano forest fragmentation on gall inducing species associated ...with four native plants species, simultaneously examining area and edge effects as well as the role of host plant availability on such effects. At edge and interior locations in each of nine forest sites in an area gradient in Central Argentina, we estimated herbivory as (1) the proportion of galled plants and (2) the number of galls per plant. Herbivory variations in relation to forest area and edge/interior locations were analyzed with generalized linear models, whereas the influence of plant availability in mediating area and edge effects was assessed by Structural Equation Models. Different responses to fragmentation were observed, depending on the insect species and also on the chosen herbivory indicator. Significant edge and area effects were detected in four and two out of ten performed models, respectively. When significant, edge effects were mostly positive and consistently direct rather than mediated by plant availability; instead, area effects varied from positive and led by plant abundance, to negative and independent of plant availability. Our study provides new evidence of a tendency for galling insects to benefit from edge conditions, while showing less consistent effects regarding forest size. Our results also suggest a very limited role for plant availability as a mechanism mediating fragmentation effects on herbivory by galling insects.
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