Maritime cognitive workload assessment

The human factor plays the key role for safety in many industrial and civil every-day operations in our technologized world. Human failure is more likely to cause accidents than technical failure, e.g. in the challenging job of tugboat captains. Here, cognitive workload is crucial, as its excess is a main cause of dangerous situations and accidents while being highly participant and situation dependent. However, knowing the captain’s level of workload can help to improve man-machine interaction. The main contributions of this paper is a successful workload indication and a transfer of cognitive workload knowledge from laboratory to realistic settings

Early Abnormal Temperature Structure of X-ray Looptop Source of Solar Flares

This Letter is to investigate the physics of a newly discovered phenomenon -- contracting flare loops in the early phase of solar flares. In classical flare models, which were constructed based on the phenomenon of expansion of flare loops, an energy releasing site is put above flare loops. These models can predict that there is a vertical temperature gradient in the top of flare loops due to heat conduction and cooling effects. Therefore, the centroid of an X-ray looptop source at higher energy bands will be higher in altitude, for which we can define as normal temperature distribution. With observations made by {\it RHESSI}, we analyzed 10 M- or X-class flares (9 limb flares). For all these flares, the movement of looptop sources shows an obvious U-shaped trajectory, which we take as the signature of contraction-to-expansion of flare loops. We find that, for all these flares, normal temperature distribution does exist, but only along the path of expansion. The temperature distribution along the path of contraction is abnormal, showing no spatial order at all. The result suggests that magnetic reconnection processes in the contraction and expansion phases of these solar flares are different.Comment: 11 pages, 4 figure

Optimizing Plant Disease Management in Agricultural Ecosystems Through Rational In-Crop Diversification

Biodiversity plays multifaceted roles in societal development and ecological sustainability. In agricultural ecosystems, using biodiversity to mitigate plant diseases has received renewed attention in recent years but our knowledge of the best ways of using biodiversity to control plant diseases is still incomplete. In term of in-crop diversification, it is not clear how genetic diversity per se in host populations interacts with identifiable resistance and other functional traits of component genotypes to mitigate disease epidemics and what is the best way of structuring mixture populations. In this study, we created a series of host populations by mixing different numbers of potato varieties showing different late blight resistance levels in different proportions. The amount of naturally occurring late blight disease in the mixture populations was recorded weekly during the potato growing seasons. The percentage of disease reduction (PDR) in the mixture populations was calculated by comparing their observed late blight levels relative to that expected when they were planted in pure stands. We found that PDR in the mixtures increased as the number of varieties and the difference in host resistance (DHR) between the component varieties increased. However, the level of host resistance in the potato varieties had little impact on PDR. In mixtures involving two varieties, the optimum proportion of component varieties for the best PDR depended on their DHR, with an increasing skewness to one of the component varieties as the DHR between the component varieties increased. These results indicate that mixing crop varieties can significantly reduce disease epidemics in the field. To achieve the best disease mitigation, growers should include as many varieties as possible in mixtures or, if only two component mixtures are possible, increase DHR among the component varieties

Endoscopic Therapy of Colonic Liver Flexure Mucocele

Colorectal mucoceles usually arise in the appendix, and colonic disease is very rare. We report the first case of a mucocele of the colonic liver flexure that was treated successfully with endoscopy. A 36-year-old man was admitted to our hospital because of abdominal distension persisting for 3 days. Colonoscopic examination revealed a round polyp in the hepatic flexure, and we performed hot snare polypectomy with argon plasma coagulation. Histologically, the polypectomy specimen was confirmed to be a mucocele, with no neoplastic changes. Follow-up examinations at 6 and 12 months showed no evidence of recurrence

Polymeric micelles based on poly(ethylene glycol) block poly(racemic amino acids) hybrid polypeptides: conformation-facilitated drug-loading behavior and potential application as effective anticancer drug carriers

In this work, racemic hybrid polypeptides poly(ethylene glycol) (PEG)-b-poly(racemic-leucine) (PRL) copolymers with different leucine residues have been synthesized and characterized. Using docetaxel as a model molecule, the high drug-loaded spherical micelles based on PEG-PRL were prepared successfully using dialysis, with a tunable particle size from 170 nm to 250 nm obtained by changing the length of the hydrophobic blocks. Facilitated drug-loading behavior (higher drug-loading ability and easier drug-loading process) of PEG-PRL compared with their corresponding levo forms (PEG-b-poly[levo leucine]) was observed and clarified for the first time. With this facilitation, the highest drug-loading content and efficiency of PEG-PRL micelles can achieve 11.2% ± 0.4% and 67.2% ± 2.4%, respectively. All drug-loaded PEG-PRL micelles exhibit a similar release behavior with a sustained release up to 72 hours. The PEG-PRL was shown to be nontoxic against MCF-7 and human umbilical vein endothelial cells up to a concentration of 100 μg/mL, displaying a good biocompatibility. Also, the docetaxel-loaded PEG-PRL micelles were more toxic than the free drug against MCF-7 human breast cancer cells – both dose and time dependent. Therefore, these high docetaxel-loaded micelles based on racemic hybrid polypeptides appear to be a novel promising nanomedicine for anticancer therapy