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Large vessels such as container ships rely on experienced pilots with extensive knowledge of the local streams and tides responsible for operating the vessel to its desired location. This work proposes estimating time-to-collision (TTC) between moving objects (i.e., vessels) using real-time video data captured from aerial drones in dynamic maritime environments. Our deep-learning-based methods utilize features optimized with realistic virtually generated data for reliable and robust object detection, segmentation, and tracking. Furthermore, we use rotated bounding box representations, obtained from fine semantic segmentation of objects, for enhanced TTC estimation accuracy. We intuitively present collision estimates as collision arrows that gradually change color to red to indicate an imminent collision. Experiments conducted in a realistic dockyard virtual environment show that our approaches precisely, robustly, and efficiently predict TTC between dynamic objects seen from a top-view, with a mean error and a standard deviation of 0.358 0.114 s, respectively, in a worst-case scenario.

In this work we present a novel end-to-end solution for tracking objects (i.e., vessels), using video streams from aerial drones, in dynamic maritime environments. Our method relies on deep features, which are learned using realistic simulation data, for robust object detection, segmentation and tracking. Furthermore, we propose the use of rotated bounding-box representations, which are computed by taking advantage of pixel-level object segmentation, for improved tracking accuracy, by reducing erroneous data associations during tracking, when combined with the appearance-based features. A thorough set of experiments and results obtained in a realistic shipyard simulation environment, demonstrate that our method can accurately, and fast detect and track dynamic objects seen from a top-view.

While artificial cyclases hold great promise in chemical synthesis, this work presents the first example of a DNA-catalyzed inverse electron-demand hetero-Diels-Alder (IEDHDA) between dihydrofuran and various α,β-unsaturated acyl imidazoles. The resulting fused bicyclic O,O-acetals containing three contiguous stereogenic centers are obtained in high yields (up to 99 %) and excellent diastereo- (up to >99:1 dr) and enantioselectivities (up to 95 % ee) using a low catalyst loading. Most importantly, these results show that the concept of DNA-based asymmetric catalysis can be expanded to new synthetic transformations offering an efficient, sustainable, and highly selective tool for the construction of chiral building blocks., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A highly enantioselective iron-catalyzed Intramolecular Inverse Electron-Demand Hetero Diels-Alder (IIEDHDA) reaction is reported. By using a chiral semicorrin ligand in the presence of 2,6-lutidine, good isolated yields and excellent enantioselectivities were observed (up to 96% ee). Thanks to the versatile postfunctionalization of the acyl-imidazole moiety, this methodology represents a unique example of the straightforward construction of highly valuable enantioenriched bicyclic dihydropyran derivatives.

The studies culminating in the synthesis of two large subunits of tautomycetin are described. The first one, fragment C1-C12 that has an anti -1,3-dimethyl system and a terminal diene unit, was accomplished in 10 linear steps in 7.4% overall yield. The second one, fragment C13-C25 which bears the sensitive anhydride framework and the majority of the stereogenic centers, was prepared in 13 linear steps (longest sequence) in 8% overall yield. Among the key transformations used, a regioselective epoxide opening, a Pd-catalyzed addition of terminal alkyne to acceptor alkyne, a Mukaiyama aldol reaction, a Yamaguchi esterification, and a homemade mild di-esterification can be cited. The chosen strategies allowed good yields, stereoselectivity, reproducibility, and scalability for several important intermediates.

The spread of antibiotic-resistant pathogens is a growing concern, and new families of antibacterials are desperately needed. Odilorhabdins are a new class of antibacterial compounds that bind to the bacterial ribosome and kill bacteria through inhibition of the translation. NOSO-95C, one of the first member of this family, was synthesized for the first time, and then a structure-activity relationships study was performed to understand which groups are important for antibacterial activity and for inhibition of the bacterial translation. Based on this study an analogue showing improved properties compared to the parent compound was identified and showed promising in vitro and in vivo efficacy against Enterobacteriaceae.

The ubiquitous presence of spirooxindole architectures with several functionalities and stereogenic centers in bioactive molecules has been appealing for the development of novel methodologies seeking their preparation in high yields and selectivities. Expansion and refinement in the field of asymmetric organocatalysis have made possible the development of straightforward strategies that address these two requisites. In this review, we illustrate the current state-of-the-art in the field of spirooxindole synthesis through the use of non-covalent organocatalysis. We aim to provide a concise overview of very recent methods that allow to the isolation of unique, densely and diversified spirocyclic oxindole derivatives with high structural diversity via the use of cascade, tandem and domino processes., Competing Interests: The authors declare no conflict of interest.

An efficient copper-catalyzed enantioselective conjugate addition of dimethylzinc to α,β- and α,β,γ,δ-unsaturated 2-acyl-N-methylimidazoles has been achieved using a chiral bidentate hydroxyalkyl-NHC ligand. The reactions proceeded with both excellent regio- and enantioselectivity (14 examples, 87-95 % ee) to afford the desired 1,4-adducts, which were easily transformed to the corresponding aldehydes, esters, and ketones. Subsequently, this powerful methodology was therefore successfully applied in the synthesis of natural products. Furthermore, an iterative process was also disclosed leading to highly desirable 1,3-desoxypropionate skeletons (up to 94 % d.e.)., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: Increases in resting-state heart rate and decreases in its variability are associated with substantial morbidity and mortality, yet contradictory findings have been reported for the effects of the mood and anxiety disorders and of antidepressants. The authors investigated heart rate and heart rate variability in a large cohort from Brazil, using propensity score weighting, a relatively novel method, to control for numerous potential confounders., Method: A total of 15,105 participants were recruited in the Brazilian Longitudinal Study of Adult Health. Mood and anxiety disorders were ascertained using the Portuguese version of the Clinical Interview Schedule-Revised. Heart rate and its variability were extracted from 10-minute resting-state electrocardiograms. Regressions weighted by propensity scores were carried out to compare participants with and without depressive or anxiety disorders, as well as users and non-users of antidepressants, on heart rate and heart rate variability., Results: Use of antidepressants was associated with increases in heart rate and decreases in its variability. Effects were most pronounced for the tricyclic antidepressants (Cohen's d, 0.72-0.81), followed by serotonin and norepinephrine reuptake inhibitors (Cohen's d, 0.42-0.95) and other antidepressants (Cohen's d, 0.37-0.40), relative to participants not on antidepressants. Only participants with generalized anxiety disorder showed robust, though small, increases in heart rate and decreases in its variability after propensity score weighting., Conclusions: The findings may, in part, underpin epidemiological findings of increased risk for cardiovascular morbidity and mortality. Many factors that have an adverse impact on cardiac activity were controlled for in this study, highlighting the importance of cardiovascular risk reduction strategies. Further study is needed to examine whether, how, and when such effects contribute to morbidity and mortality.

A mild, practical, and simple procedure for peptide-bond formation is reported. Instead of activation of the carboxylic acid functionality, the reaction involves an unprecedented use of activated α-aminoesters. The method provides a straightforward entry to dipeptides and was effective when a sensitive cysteine residue was used, as no epimerization was detected in this case. The applicability of this method to iterative peptide synthesis was illustrated by the synthesis of a model tetrapeptide in the challenging reverse N→C direction., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This study aimed to quantify the levels of resveratrol, coumarin, and other bioactives in pulps and by-products of twelve tropical fruits from Brazil obtained during pulp production process. Pineapple, acerola, monbin, cashew apple, guava, soursop, papaya, mango, passion fruit, surinam cherry, sapodilla, and tamarind pulps were evaluated as well as their by-products (peel, pulp's leftovers, and seed). Total phenolic, anthocyanins, yellow flavonoids, β-carotene and lycopene levels were also determined. Resveratrol was identified in guava and surinam cherry by-products and coumarin in passion fruit, guava and surinam cherry by-products and mango pulp. These fruit pulp and by-products could be considered a new natural source of both compounds. Overall, fruit by-products presented higher (P<0.05) bioactive content than their respective fruit pulps. This study provides novel information about tropical fruits and their by-products bioactive composition, which is essential for the understanding of their nutraceutical potential and future application in the food industry., (Published by Elsevier Ltd.)

Data on flowering phenology and pollination of Peperomia species are virtually non-existent. This study presents data on the pollination biology of eight Peperomia species from south-eastern Brazil, including the flowering phenology, pollination system, and reproductive success. Data on flowering phenology were recorded weekly and exclusion experiments on inflorescences provided data on autonomous self- and wind pollination. Direct visual observations were made and insect visits were recorded. Four Peperomia species showed continuous flowering, while the others were seasonal and flowered in the wet season. Pollination by wind and Syrphidae was confirmed for two self-incompatible Peperomia species. The remaining species are self-compatible and their high fruit set may be accounted for by autonomous self-pollination and perhaps agamospermy. Although the floral morphology of Peperomia species suggests wind- and/or insect pollination, most of the species studied exhibit autogamy and perhaps agamospermy as the main method of reproduction.

The advent of AIDS in families, following the chronic evolution of the illness, has produced crisis situations unknown until now. With the objective of knowing this new reality better, 20 caregivers of AIDS patients were interviewed in southeastern Brazil. The collected data were analyzed using a qualitative method. The results showed difficulties regarding caregiving, such as a lack of orientation, materials, transport, and people to share the role of caregiver, as well as emotional difficulties, such as fears from infection, revulsion, pity, and impotence in the face of death. The role of families is essential in patient assistance, due to the inability of the health system to attend to all AIDS patients. Nevertheless, these families have to receive support mainly from nurses, in order to be helped in executing an aid plan to the ill person at home. Nurses and health care.

This study aimed at identifying the incidence of drug intake errors and the main therapy-related difficulties among AIDS patients as well as at proposing measures to increase patients' adherence to treatment. Sixty-one patients with AIDS assisted by the University Hospital of São Paulo State University at Campinas were interviewed. The most frequent errors concerned the combinations of drugs and the length of fasting. The difficulties reported were adverse effects and the variety of drugs. Based on these data, the authors proposed the use of an illustrated guide for drug-related information. It is hoped that individualized guidance can contribute to minimize errors concerning adherence to therapy.

Gold-labeled albumin and transferrin were used to follow at the ultrastructural level the early events and the effect of low temperature on protein uptake by Trypanosoma cruzi epimastigotes. In parasites incubated for 5 min at 28 degrees C with protein-gold complexes, extracellular markers were found only at the cytostome and/or the flagellar pocket regions, whereas intracellular gold particles were detected inside small uncoated vesicles located nearby. Within 10 min, labeling was also observed in uncoated vesicles close to the nucleus. Only after 30 min could the tracers be detected in the reservosomes. Weak labeling in the cytostome and flagellar pocket of parasites incubated at 4 degrees C with the albumin-gold solution indicated that albumin uptake occurred by fluid-phase pinocytosis. On the other hand, intense labeling at the cytostome was observed in parasites incubated at 4 degrees C with gold-labeled transferrin, showing that receptor-mediated endocytosis occurs mainly at this site. Both proteins were absent from the cells at 4 degrees C and 12 degrees C. Raising the temperature from 12 degrees C to 28 degrees C led to transferrin labeling in intracellular vesicles dispersed throughout the cytoplasm, but not in reservosomes. Our results suggest that low temperatures affect the transport and pinching of endocytic vesicles as well as the rate of delivery of transferrin to reservosomes.

Recent evidence suggests that AD is associated with the development of cerebral amyloid angiopathy and with significant changes in the blood-brain barrier glucose transporter and basement membrane protein alterations. It is likely that these changes significantly contribute to chronic cerebral hypoperfusion, possibly resulting in progressive neural death in AD. To investigate the etiology of these changes, we have analyzed postmortem tissue sections of frontal cortex of moderately demented AD cases, stained using both single-label and double-label immunocytochemistry to detect vessels and beta-amyloid. The resultant color images are analyzed using HSV (hue-saturation-value) color image analysis, shape analysis, and histogram analysis techniques. These analyses let us segment the tissue images for further statistical analyses.

The present study aims to characterize the profile of people studying in auxiliary nurse courses at the city of Campinas. The predominantly characteristics were: ages between 18 and 30 years old, majority female, single and catholic. The major part of the studied population does not work in nursing area, being the mainly motivation to begin the course the possibility of helping other people. Their difficulties were returning to school, conciliating the study schedule with other activities and paying the course.

This paper describes learning rules using simultaneous perturbation for a neurocontroller that controls an unknown plant. When we apply a direct control scheme by a neural network, the neural network must learn an inverse system of the unknown plant. In this case, we must know the sensitivity function of the plant using a kind of the gradient method as a learning rule of the neural network. On the other hand, the learning rules described here do not require information about the sensitivity function. Some numerical simulations of a two-link planar arm and a tracking problem for a nonlinear dynamic plant are shown.

The curative feature of health of university students has gained more attention. This study evaluated the needs of university students for an orientational and educational service on mental health. For mental health orientation and education, an individual consultation service, was implanted as well as lectures about the theme. This project gathered data and information important to the effective institutionalization of the service.

The proposal for a visual acuity test (A.V.) arose from a survey conducted among School Children of the "Ciclo Básico (C.B.)" i.é., the first two years of Elementary School in S. Carlos, S. Paulo State, Brazil. Nine schools participated in this study. The teachers were properly trained to apply the A. V. and squinting tests according to a standardized procedure. Of 2,025 children tested, 88.1% showed levels of A. V. higher than 0.8, and a squinting prevalence of 2.17%. When the application of the test was over, each school presented its proposals for the systematical application of such tests. These proposals had a common point: the test should be applied by the teachers themselves under the supervision of the coordinators of the C. B. The school nurse would be responsible for giving overall assistance to all the activities of the program at all levels.

The unified approach to optimal image interpolation problems presented provides a constructive procedure for finding explicit and closed-form optimal solutions to image interpolation problems when the type of interpolation can be either spatial or temporal-spatial. The unknown image is reconstructed from a finite set of sampled data in such a way that a mean-square error is minimized by first expressing the solution in terms of the reproducing kernel of a related Hilbert space, and then constructing this kernel using the fundamental solution of an induced linear partial differential equation, or the Green's function of the corresponding self-adjoint operator. It is proved that in most cases, closed-form fundamental solutions (or Green's functions) for the corresponding linear partial differential operators can be found in the general image reconstruction problem described by a first- or second-order linear partial differential operator. An efficient method for obtaining the corresponding closed-form fundamental solutions (or Green's functions) of the operators is presented. A computer simulation demonstrates the reconstruction procedure.

Rotavirus testing was performed on fecal samples of 607 infants and young children aging from 0 to 6 years with acute diarrhoea between May 1986 and April 1990. Samples were analyzed by polyacrylamide gel electrophoresis (PAGE). Rotaviruses were detected in 123 samples (20.27%); from those, 107 (87.00%) were classified as subgroup II (long profile). Rotaviruses were not detected in the control group of healthy children, but it were present in 7.80% of the children hospitalized for other causes but acute diarrhoea. Most of the children with rotavirus infection ranged from 6 to 24 months of age (73.98%). The mean of positive cases during the rainy months (October to April) was of 9.60% and during the dry period was of 34.48%. The highest values were 53.17 and 73.27% in June and July, the coldest months of the year.

A technique is presented for feature extraction of a waveform y based on its Tauberian approximation, that is, on the approximation of y by a linear combination of appropriately delayed versions of a single basis function x, i.e., y(t) = ¿M i = 1 aix(t - ¿i), where the coefficients ai and the delays ¿i are adjustable parameters. Considerations in the choice or design of the basis function x are given. The parameters ai and ¿i, i=1, . . . , M, are retrieved by application of a suitably adapted version of Prony's method to the Fourier transform of the above approximation of y. A subset of the parameters ai and ¿i, i = 1, . . . , M, is used to construct the feature vector, the value of which can be used in a classification algorithm. Application of this technique to the classification of wide bandwidth radar return signatures is presented. Computer simulations proved successful and are also discussed.

Image transform coding is first briefly reviewed using conventional viewpoints. Then a new spatial domain interpretation is given to image transform coding. An improvement based on this viewpoint for the Fourier transform coding, which possesses simple spatial domain relations, is presented.

The purpose of this trial was to evaluate the effect of tiapride in alcohol withdrawal. The same very strict protocol was applied to each of 90 hospitalized male patients. Starting from 12 intravenous vials daily, in 4 doses, dosage was slowly brought down to 3 tablets per day, in 3 doses, by the 5th day. Effectiveness of Tiapride proved excellent, as soon as the first four days, mainly on psychiatric and digestive manifestations, while it was satisfactory on pain and less so on tremor. Overall tolerance was good. Attention is drawn to the very rapid action of Tiapride, which results in a 50% decrease in the duration of the hospital stay.