Facial expressions of emotion in humans are believed to be produced by contracting one’s facial muscles, generally called action units. However, the surface of the face is also innervated with a ...large network of blood vessels. Blood flow variations in these vessels yield visible color changes on the face. Here, we study the hypothesis that these visible facial colors allow observers to successfully transmit and visually interpret emotion even in the absence of facial muscle activation. To study this hypothesis, we address the following two questions. Are observable facial colors consistent within and differential between emotion categories and positive vs. negative valence? And does the human visual system use these facial colors to decode emotion from faces? These questions suggest the existence of an important, unexplored mechanism of the production of facial expressions of emotion by a sender and their visual interpretation by an observer. The results of our studies provide evidence in favor of our hypothesis. We show that people successfully decode emotion using these color features, even in the absence of any facial muscle activation. We also demonstrate that this color signal is independent from that provided by facial muscle movements. These results support a revised model of the production and perception of facial expressions of emotion where facial color is an effective mechanism to visually transmit and decode emotion.
Small pelagic fishes are used for human consumption, fishmeal and fish oil. They constitute 25% of global fish catch and have been of considerable conservation concern because of their intermediate ...position in aquatic food webs, often being a dominant dietary component of marine predators. This paper provides an overview of trends in abundance and fishing pressure on small pelagic fish stocks from single‐species scientific assessments that constitute 60% of global small pelagic catch. While most individual stocks have exhibited wide variability in abundance (typical of small pelagics compared with other fish taxa), across stocks there has been remarkable stability in average fishing pressure and biomass since 1970. On average, since 1970, the biomass of assessed small pelagic stocks is estimated to have been slightly above the biomass that would produce maximum sustainable yield, but estimation of this quantity for highly fluctuating stocks is quite uncertain. There were significant differences among assessed regions, with the Mediterranean and Black Sea of greatest concern for high and growing fishing pressure. The 40% of global small pelagic fish catch not covered by single‐species quantitative stock assessments since 1970 comes largely from Asia, where catches have continued to increase. At regional levels, the average abundance of assessed small pelagic fish is largely unrelated to average fishing pressure, which we argue results both from the portfolio effect, where numerous stocks fluctuate with little correlation in abundance, and from the short life span of small pelagics coupled with recruitment largely independent of spawning abundance.
Global status of groundfish stocks Hilborn, Ray; Hively, Daniel J.; Loke, Nicole Baker ...
Fish and fisheries (Oxford, England),
September 2021, 2021-09-00, 20210901, Letnik:
22, Številka:
5
Journal Article
Recenzirano
Odprti dostop
We review the status of groundfish stocks using published scientific assessments for 349 individual stocks constituting 90% of global groundfish catch. Overall, average stock abundance is increasing ...and is currently above the level that would produce maximum sustainable yield (MSY). Fishing pressure for cod‐like fishes (Gadiformes) and flatfishes (Pleuronectiformes) was, for several decades, on average well above levels associated with MSY, but is now at or below the level expected to produce MSY. In contrast, fishing pressure for rockfishes (Scorpaeniformes) decreased from near MSY‐related levels in the mid‐1990s, and since the mid‐2000s has remained on average at only one third of MSY‐related levels. Regions with the most depressed groundfish stocks are the Northwest Atlantic and the Pacific coast of South America, while stocks from the Northeast and Eastern Central Pacific, Northeast Atlantic, Southeast Atlantic and Southwest Pacific tend to have greatest average abundance relative to MSY‐based reference points. In the most recent year available for each stock, the catch was only 61% of MSY. Equilibrium yield curves indicate that 76% of global potential groundfish yield could be achieved using current estimates of fishing pressure. 15% of this is lost by excess fishing pressure, 67% results from lower than optimal fishing pressure on healthy stocks and 18% is lost from stocks currently overfished but rebuilding. Thus, there is modest opportunity to increase catch of global groundfish fisheries by reducing overfishing on some stocks, but more by increasing harvest on others. However, there may be other reasons not to fully exploit these stocks.
Neuromorphic photonics is a new paradigm for ultra-fast neuro-inspired optical computing that can revolutionize information processing and artificial intelligence systems. To implement practical ...photonic neural networks is crucial to identify low-cost energy-efficient laser systems that can mimic neuronal activity. Here we study experimentally the spiking dynamics of a semiconductor laser with optical feedback under periodic modulation of the pump current, and compare with the dynamics of a neuron that is simulated with the stochastic FitzHugh-Nagumo model, with an applied periodic signal whose waveform is the same as that used to modulate the laser current. Sinusoidal and pulse-down waveforms are tested. We find that the laser response and the neuronal response to the periodic forcing, quantified in terms of the variation of the spike rate with the amplitude and with the frequency of the forcing signal, is qualitatively similar. We also compare the laser and neuron dynamics using symbolic time series analysis. The characterization of the statistical properties of the relative timing of the spikes in terms of ordinal patterns unveils similarities, and also some differences. Our results indicate that semiconductor lasers with optical feedback can be used as low-cost, energy-efficient photonic neurons, the building blocks of all-optical signal processing systems; however, the length of the external cavity prevents optical feedback on the chip.
Pig farming is an important activity in the economic development of Mexico with millions of tons of meat produced annually. Antibiotics are used in therapeutic dose to prevent diseases, and sometimes ...as growth promoters. These compounds are not completely metabolized; they are carried into the environment in its active form at concentrations that could induce antibiotic resistance in bacteria, which could be transferred to human pathogens by horizontal gene transfer. The objective of this work was to develop methods of analysis for simultaneous quantification of the antibiotics Oxytetracycline (OXT), Chlortetracycline (CLT), Enrofloxacin (ENRO) and Ciprofloxacin (CIPRO) by field-amplified sampling injection in capillary zone electrophoresis (FASI-CZE). The method was validated by parameters of (1) linearity, obtaining a lineal range of 0.05 at 1 μg mL−1 for ENRO and CIPRO, and from 0.1 to 1 μg mL−1 for OXT and CLT; (2) precision, obtaining values <5% of standard deviation for CIPRO and ENRO and <10% of standard deviation for OXT and CLT; (3) accuracy, with recovery values from 93 to 115%; (4) selectivity, with values of resolution >2 for the all antibiotics tested. To prove the method, a sample of wastewater from a local pig farm was analyzed, detecting a concentration of 0.140 ± 0.009 for OXT. This concentration was higher than the minimal selective concentration, indicating the point in which resistance to a determined antibiotic could develop. The methods were validated with precision and sensitivity comparable to chromatographic methods, which can be used to analyze wastewater from pig farms directly.
Turbulent mixing in pilot‐scale cultivation systems influences the productivity of photoautotrophic cultures. We studied turbulent mixing by applying particle image velocimetry and acoustic doppler ...velocimetry to pilot‐scale, flat‐panel photobioreactor, and open‐channel raceway. Mixing energy inputs were varied from 0.1 to 2.1 W·m−3. The experimental results were used to quantify turbulence and to validate computational fluid dynamics models, from which Lagrangian representations of the fluid motion in these reactors were derived. The results of this investigation demonstrated that differences in mixing energy input do not significantly impact the structure of turbulence and the light/dark cycling frequencies experienced by photoautotrophic cells within the reactors. The experimental and computational results of our research demonstrated that well‐mixed conditions exist in pilot‐scale, flat‐panel photobioreactors and open‐channel raceways, even for relatively low mixing energy inputs.
Study of the implications of turbulent mixing on the light/dark cycling frequencies experienced by microalgae and cyanobacteria in pilot‐scale flat‐panel photobioreactor and raceway. The research approach consists of (i) experimental fluid mechanics using particle image velocimetry (PIV) and acoustic doppler velocimetry (ADV), (ii) validation of computational fluid dynamics (CFD) models, and (iii) turbulence characterization and particle motion.
The páramo, a collection of Neotropical alpine ecosystems, plays a prominent role in ecosystem services (ESs), providing water supply and regulation, conservation of biodiversity, and carbon storage ...in soil. The establishment of pine plantations for carbon sequestration and wood production has recently raised questions concerning the possible impact on the páramo’s ES. This study identifies the main stakeholders in this field and compares and contrasts their perceptions of the impact of pine plantations on the páramo’s ES, because the disparity among stakeholders’ perceptions must be addressed to achieve sustainable management. The data were gathered using 56 semi-structured interviews and were qualitatively analyzed. The results show that the main stakeholder groups (landowners, local government officials, foresters, and nature conservationists) acknowledge the important ES of the plantations. The perception of plantation impact varies among and within stakeholder groups, however, on specific functions, such as water provision, carbon storage, erosion prevention, and habitat function for wildlife and natural vegetation. Consideration and integration of these perceptions can help policy makers and organizations develop sustainable policies for the future management of the páramo ecosystem.
To recreate or substitute tissue in vivo is a complicated endeavor that requires biomaterials that can mimic the natural tissue environment. Gelatin methacrylate (GelMA) is created through covalent ...bonding of naturally derived polymer gelatin and methacrylic groups. Due to its biocompatibility, GelMA receives a lot of attention in the tissue engineering research field. Additionally, GelMA has versatile physical properties that allow a broad range of modifications to enhance the interaction between the material and the cells. In this review, we look at recent modifications of GelMA with naturally derived polymers, nanomaterials, and growth factors, focusing on recent developments for vascular tissue engineering and wound healing applications. Compared to polymers and nanoparticles, the modifications that embed growth factors show better mechanical properties and better cell migration, stimulating vascular development and a structure comparable to the natural-extracellular matrix.
•N1112OHAla acts as efficient phase promoter in aqueous solutions of Triton X-100.•The hormone 17-β estradiol was mostly partitioned to the surfactant-rich phase.•The antibiotics separation strongly ...depended on the feed concentration.•The addition of CTAB allowed improving the extraction at levels higher than 90%.
The generalized use of antibiotics and hormones in swine feed has triggered a growing concern on their presence in wastewater effluents and manure. Therefore, the implementation of strategies for their removal is a matter of practical significance and the synthesis of biocompatible ionic liquids to be used as segregation agents in aqueous waste effluents could be a suitable means for removing these emerging contaminants. In this work, the salting out capacity of cholinium alaninate, (N1112OHAla) in aqueous streams containing surfactants (Triton X-100) was demonstrated. Afterwards, its ability to separate a hormone (17-β estradiol) and antibiotics belonging to tetracycline and fluoroquinolone families was investigated in an aqueous synthetic swine effluent at environmental conditions. It was checked that the cautious selection of the feed compositions allowed high levels of hormone extraction (E) and partition coefficients (K): E > 90% and K > 13.86, in surfactant rich-phase. Antibiotics migrated to any of the two phases depending on system compositions. However, the decisive addition of a cationic surfactant (2% CTAB) led to increased extraction efficiencies of chlortetracycline (K = 15.77 and E = 92.5%), proving the versatility of the process.