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El auge de la movilidad vehicular durante el siglo XX significó el reemplazo progresivo de la movilidad peatonal y de una acción primaria del individuo: el caminar. Sin embargo, los conflictos generados por el crecimiento urbano y el deterioro ambiental han traído cuestionamientos acerca de las formas de pensar e intervenir nuestras ciudades dando lugar a una transformación gradual de paradigmas de movilidad. Hoy, la movilidad peatonal y la movilidad no motorizada se han vuelto temas recurrentes, tanto en agendas públicas como en la construcción del espacio urbano, visibilizando una importante variedad de reflexiones sobre el diseño, la calidad y la experiencia espacial. Para evidenciar la importancia de los entornos peatonales como espacio clave de las practicas cotidianas de movilidad sostenible y partir de una propuesta metodológica desarrollada como parte de un trabajo de maestría, esta ponencia presenta una propuesta de diseño aplicada al corredor Bolívar, entre calle 44 San Juan y Calle, en el centro de Medellín. The rise of vehicular mobility during the 20th century led to a progressive decline of pedestrian mobility and one of the primary activities of human beings: walking. However, conflicts generated by urban growth and environmental deterioration have raised questions about how we think and intervene in our cities, giving rise to a gradual shift in mobility paradigms. Today, pedestrian, and non-motorized mobility have reemerged as central topics for both public agendas and the intervention on urban space. This shift has brought into the debate a variety of reflections about spatial design and quality and the human experience of space. To demonstrate the importance of pedestrian environments as a key space for sustainable mobility practices and based on a methodological proposal developed as part of a master's work, this paper presents a design proposal applied to Bolívar corridor, between Calle 44 San Juan and Calle, in the center of Medellín.

The common snook Centropomus undecimalis is one of the main commercial fish species in the Caribbean region, including Colombia, where its populations have drastically decreased due to overfishing and environmental degradation. Thus, there is a market imbalance between the availability of snook products and their demand by consumers, which creates an opening for fraudulent actions such as species substitutions. Legislation in Colombia (and most Caribbean countries) lacks effective tools for the easy and rapid detection of frauds. Furthermore, there are very few studies published in scientific journals addressing this issue, of which none include C. undecimalis as the target species. Therefore, in order to investigate the existence of mislabeling in common snook products in Santa Marta, the present study analysed 44 frozen snook fillets from the five commercial brands available in the city. Moreover, 15 fresh snook fillets from six of the main fish markets were also analysed. To discover the frequency of possible frauds in labeling, samplings were carried out in July, September and November of 2019. Sample analyses involved the identification of each fillet at species level through molecular barcodes (16S-rRNA and COI), whose sequences were verified using BLAST and BOLD, and corroborated by a phylogenetic analysis. As a result, an astonishing 98% of the supermarkets fillets were found to be fraudulent, contrasting with a single case registered in the fish shop samples. The species used to substitute snook include the Pacific bearded brotula Brotula clarkae (38 samples), the Nile perch Lates niloticus (4 samples) and the acoupa weakfish Cynoscion acoupa (1 sample). Based on these results, there is a high rate of fraudulent labeling in the marketing of common snook in the city of Santa Marta, which calls for urgent actions to be taken by the corresponding authorities., Snook; Fraud; Species substitution; COI; 16S-rRNA.

Basadas en la perspectiva cultural de los problemas públicos (Gusfield, 2014), exploramos el proceso de construcción de las políticas de movilidad urbana como un fenómeno social y como objeto de acción pública en Bogotá y Belo Horizonte, a partir de la década de los noventa. Mediante un análisis de contenido de los instrumentos de política pública, tanto de carácter territorial como sectorial, identificamos transformaciones en la categoría de movilidad y la construcción de nuevas identidades de los agentes urbanos en las que el movimiento tiene un papel central. Observamos que en este periodo se promovieron transformaciones de la cultura de ordenamiento territorial, en el ámbito local, que valorizaron el concepto de movilidad. También identificamos un creciente interés por agentes urbanos que tenían escasa visibilidad pública –como peatón y ciclista, entre otros–, e identificamos cuatro mecanismos discursivos utilizados para describir, regular, controlar y construir la identidad de los sujetos móviles: clasificación, omisión, estigmatización y metonimias.

Objective. To evaluate the effect of three diets on the growth of juvenile common snook (Centropomus undecimalis) maintained in freshwater ponds Materials and methods. 108 juvenile of common snook were homogenous and randomly distributed in a pond, divided into 9 corrals of 50 m2. Three diets were applied (D1: commercial food for trout, 45% protein; D2: commercial food for cobia, 50% protein and D3: fresh fish, 17.52% protein). The experimental treatments were assigned in triplicate and diets were supplied in two daily doses. Biometrics were performed every 20 days to assess: weight, size, Length-Weight correlation, Feed Conversion Factor (FCA), Condition Factor (K), Specific Growth Rate (SGR) and survival; during 120 days. The results were evaluated with a one-way ANOVA, when differences (p, Objetivo. Evaluar el efecto de tres dietas sobre el desempeño de juveniles de róbalo (Centropomus undecimalis) mantenidos en estanques de agua dulce. Materiales y métodos. 108 juveniles de róbalo fueron distribuidos homogénea y aleatoriamente en un estanque dividido en 9 corrales de 50 m2. Se suministraron tres dietas (D1: alimento comercial para truchas, 45% de proteína; D2: alimento comercial para cobia, 50% de proteína y D3: pescado fresco, 17.52% de proteína). Los tratamientos experimentales fueron asignados por triplicado y se les suministró cada dieta en dos dosis diarias. Se realizaron biometrías cada 20 días evaluando: peso, talla, relación Longitud-Peso, Factor de Conversión Alimenticia (FCA), Factor de Condición (K), Tasa Específica de Crecimiento (SGR) y supervivencia final; durante 120 días. Los resultados fueron evaluados con un ANOVA a una vía, cuando no se encontraron diferencias (p>0.05) las medias fueron comparadas mediante la prueba de la Mediana de Mood. En caso de significación estadística del ANOVA, se aplicó la prueba de comparación múltiple de Tukey HSD. Resultados. Se encontraron diferencias estadísticas entre los tratamientos, mostrando los mayores crecimientos y rendimientos con D2, con valores de SGR=0.65±0.09 g/día; FCA=3.76 y K=0.81±0.06. La supervivencia fue D1=51.4%, D2=50% y D3=77.8% sin diferir estadísticamente entre las diferentes dietas. Conclusiones. El cultivo de esta especie en estanques de agua dulce con suministro de alimento comercial para cobia es viable en términos de crecimiento y ganancia en peso.

In the underwater environment, the properties of light (intensity and spectrum) change rapidly with depth and water quality. In this article, we have described how and to what extent lighting conditions can influence the development, growth, and survival of zebrafish. Fertilized eggs and the corresponding larvae were exposed to different visible light wavelengths (violet, blue, green, yellow, red, and white) in a 12-h light–12-h dark (LD) cycle until 30 days posthatching (dph), when the expression of morphometric parameters and growth (igf1a, igf2a)- and stress-related (crh and pomca) genes were examined. Another group of larvae was raised under constant darkness (DD) until 5 or 10 dph, after which they were transferred to a LD of white light. A third group remained under DD to investigate the effects of light deprivation upon zebrafish development. The results revealed that the hatching rate was highest under blue and violet light, while total length at 30 dph was greatest under blue, white, and violet light. Red light led to reduced feeding activity and poor survival (100% mortality). Larvae raised under constant white light (LL) showed a higher proportion of malformations, as did larvae raised under LD violet light. The expression of growth and stress factors was upregulated in the violet (igf1a, igf2a, pomca, and chr) and blue (igf2a) groups, which is consistent with the higher growth recorded and the higher proportion of malformations detected under the violet light. All larvae kept under DD died before 18 dph, but the survival rates improved in larvae transferred to LD at 5 dph and at 10 dph. In summary, these findings revealed that lighting conditions are crucial factors influencing zebrafish larval development and growth.

Fish have an internal biological clock that drives their daily rhythms, including those of feeding and reproduction. The European sea bass has been reported to exhibit a phase inversion of its diel feeding pattern: nocturnal in winter (coinciding with the spawning period) and diurnal during the remainder of the year. In this study, we investigated the locomotor activity of sea bass during the spawning and resting periods as well as the possible existence of a daily spawning rhythm by calculating the number of eggs (and their viability) released every hour. The results showed that sea bass locomotor activity was clearly nocturnal (68 ± 4.3% of the daily activity displayed at night) during the spawning season and mostly diurnal (65.5 ± 7.5% of the activity displayed during the day) out of the reproductive period. Spawning occurred during the dark phase with two peaks, 6 and 11 h after lights off. Egg viability was highest in the batch released near the spawning peaks. These findings could be useful for optimizing egg production and to improve hatchery practices, which should take into account the reproduction rhythms of sea bass.

The performance and survival of fish larvae are strongly influenced by their surrounding photic environment. The aim of this study was to investigate the effect of light characteristics (spectrum and photoperiod) on the feeding and locomotor behaviors of European sea bass larvae and its prey ( Artemia sp.). To this end, constant light (LL), constant darkness (DD) and 12:12 h LD cycles of red, blue or white LED lights were applied from 1 to 30 days post-hatching. The Modal Action Patterns (swimming duration, orientation, capture, miss and pass frequencies) of larvae and Artemia distribution in the tank were video recorded and analyzed using newly developed tracking software. The results showed that under LD B the phototactic response of sea bass larvae led to a significatively homogeneous distribution in the tanks and aquaria, while under LD W and LL the highest larvae density (52%) was seen on the tank walls. LD B and LD W resulted in longer swimming duration and earlier weaning. Larvae exposed to darkness and red light showed the lowest swimming and feeding activity, and a higher aggregation tendency of both fish larvae and the live prey. White light exposure resulted in a strong phototactic response from fish larvae and Artemia , which consisted of a tendency to congregate at the corners or close to the walls of the tank/aquaria. Artemia hatching rate under blue light was highest (56.5 ± 2.9%) in contrast with red light (26.3 ± 1.4%) and total darkness (27.9 ± 3.9). These results showed that the relationship between the behavioral responses of sea bass larvae and Artemia is strongly affected by lighting conditions, which has both basic and practical implications for understanding their behavioral ecology and for improving culture protocols.

Light is a key environmental factor that synchronizes all life-stages of fish, from embryo development to sexual maturation. The underwater photo-environment is complex since light characteristics (i.e. intensity, photoperiod and spectrum) depend on the absorbance properties of the water column. The aim of this paper is to review the effects of artificial lighting conditions on the performance, development and welfare of some fish larvae of commercial interest. Reviewed results show that larvae were significantly affected by light characteristics. For example, European sea bass and sole larvae achieved the best performance, and showed fastest development and lowest degree of deformity under a light/dark cycle using blue light (half-peak bandwidth = 435–500 nm), conditions which were the closest to their natural aquatic environment. However, constant light (LL) or constant darkness (DD) was shown to negatively affect normal larval development and resulted in increased malformations and poor survival in most of the studied species. Similar results have been observed in other fish larvae such as Atlantic cod, which performed better under short wavelengths (blue and green). These findings highlight the role of lighting conditions during the early development of fish larvae and should be taken into account for the optimization of rearing protocols in fish hatcheries as juvenile supply is one of the main production bottlenecks.

36 p., il., y bibliografía, This paper investigates the impact of different thermo- and photo-cycles of distinct wavelengths on Solea senegalensis larvae from day 1 to 30 post-hatching. In experiment 1, larvae were exposed to 12h light:12h dark (12L:12D) cycle and (A) constant temperature (20.7°C), (B) thermocycle of 12h thermophase: 12h cryophase, 22.1°C day: 19.0°C night (referred to as TC) or (C) 12h cryophase: 12h thermophase, 19.2°C day: 22.0°C night (referred to as CT). In experiment 2, larvae were kept under constant temperature (20.8°C) and exposed to (A) continuous light (LL), (B) continuous darkness (DD), and LD 12L:12D cycles of (C) white light (LDW), (D) blue light (LDB) or (E) red light (LDR). The sole larvae achieved the best performance, and showed fastest development and lowest degree of deformity under natural thermocycle conditions (TC) with a deformity percentage of 31.1% and LDB cycles with 27.7% of malformation, conditions which were nearest their natural aquatic environment. Larvae reared under TC started eye migration at 9day post-hatching (DPH), while larvae exposed to CT started eye migration at 11 DPH. In larvae under the LDB treatment the migration of the eye started earlier than in the other treatments (9 DPH), while larvae reared under LL and DD photoperiods died before metamorphosis. These findings highlight the importance of light and temperature cycles during the early development of S. senegalensis larvae, which should be taken into consideration in experimental or rearing protocols., This research was funded by the Spanish Ministry of Science and Innovation (MICINN) by projects “Circasole” AGL2007-66507-C02-02 and AQUAGENOMICS 28502 (Consolider-Ingenio Program), and SENECA by project 05690/PI/07 to Francisco Javier Sánchez Vázquez.

Objetivo: Determinar la frecuencia de hallazgos radiográficos en las radiografías panorámicas de los pacientes que acudieron a la Universidad Santo Tomás en el período 2010-2012.Materiales y métodos: Se realizó un estudio observacional descriptivo retrospectivo con fuentes secundarias que evaluó un total de 766 radiografías que cumplieron con los criterios de elegibilidad, los investigadores de este estudio realizaron una estandarización de hallazgos radiográficos y elaboraron un formato que facilitó el registro de la información.Resultados: De las 766 radiografías evaluadas 457 (59,7%) pertenecían a mujeres, las lesiones más prevalentes se encontraron en maxilar superior, siendo las radiolucidas las más comunes con 284 (37,1%) casos, dentro de las anomalías dentales se encontró que la dilaceración fue la más frecuente 167 (21,8%); otros hallazgos como reabsorción radicular 129 (6,8%) fueron también evidentes.Conclusiones: Las lesiones radiolucidas uniloculares periapicales, la dilaceración y la hipertrofia de cornetes fueron los hallazgos más frecuentes que se encontraron en este estudio.[Rueda SJ, Gallardo EY, Villamizar EN, Díaz M. Rueda SJ. Frecuencia de hallazgos radiográficos en las radiografías panorámicas de pacientes atendidos en la Universidad Santo Tomás: período 2010-2012. Ustasalud 2015;14:19-24] Objective: to determine the prevalence of radiographic findings in the panoramic radiographs of patients who attending to Universidad Santo Tomás University since 2010-2012.Methods: We executed a retrospective descriptive observational study that evaluated a total of 766 radiographs that met the eligibility criteria, the researchers made a standardization of radiographic findings and designed a format that registered the information and data.Results: a total of 766 radiographs were evaluated, 457 (59.7%) belonged to women, most of the findings were located in the upper jaw, and corresponded to radiolucent lesions with 284 (37.1%) cases, among dental anomalies, laceration was the most frequent 167 (21.8%); Other findings such as radicular resorption 129 (6.8%) were also evident.Conclusions: panoramic radiography allows an overview of the jaws and shows hidden pathologies that do not become manifest clinically.

During early development, most organisms display rhythmic physiological processes that are shaped by daily changes in their surrounding environment (i.e., light and temperature cycles). In fish, the effects of daily photocycles and their interaction with temperature during early developmental stages remain largely unexplored. We investigated the existence of circadian rhythms in embryonic development and hatching of three teleost species with different daily patterns of behavior: diurnal (zebrafish), nocturnal (Senegalese sole), and blind, not entrained by light (Somalian cavefish). To this end, fertilized eggs were exposed to three light regimes: 12 h of light: 12 h of darkness cycle (LD), continuous light (LL), or continuous darkness (DD); and three species-appropriate temperature treatments: 24°C, 28°C, or 32°C for zebrafish and cavefish and 18°C, 21°C, or 24°C for sole. The results pointed to the existence of daily rhythms of embryonic development and hatching synchronized to the LD cycle, with different acrophases, depending on the species: zebrafish embryos advanced their developmental stage during the light phase, whereas sole did so during the dark phase. In cavefish, embryogenesis occurred within 24 h post fertilization (hpf) at the same pace during day or night. The hatching rhythms appeared to be controlled by a clock mechanism that restricted or "gated" hatching to a particular time of day/night (window), so that embryos that reached a certain developmental state by that time hatch, whereas those that have not wait until the next available window. Under LL and DD conditions, hatching rhythms and the gating phenomenon persisted in cavefish, in zebrafish they split into ultradian bouts of hatching occurring at 12-18-h intervals, whereas in sole DD and LL produced a 24-h delay and advance, respectively. Hatching rates were best under the LD cycle and the reported optimal temperature for each species (95.2±2.7% of the zebrafish and 83.3±0.1% of the cavefish embryos hatched at 28°C, and 93.1±2.9% of the sole embryos hatched at 21°C). In summary, these results revealed that hatching rhythms in fish are endogenously driven by a time-keeping mechanism, so that the day and time of hatching are determined by the interplay between the developmental state (temperature-sensitive) and the circadian clock (temperature-compensated), with the particular phasing being determined by the diurnal/nocturnal behavior of the species.

This study investigates how the characteristics (spectrum and photoperiod) of artificial light affect European sea bass eggs and larvae from − 1 to 40 days post-hatching. Fertilised eggs and larvae were reared under five different light treatments: 12L:12D red light (LDR; half-peak bandwidth = 641–718 nm), 12L:12D blue light (LDB; half-peak bandwidth = 435–500 nm), 12L:12D broad-spectrum white light (LDW; 367 < λ < 1057 nm), 24L:0D broad-spectrum white light (LL) and 0L:24D (DD). The results showed that total length at day post-hatching 40 was significantly larger in larvae reared under LDB (15.4 ± 0.6 mm) and LL (15.2 ± 0.6 mm) than in larvae reared under LDR (11.7 ± 0.7 mm). Overall wet weight was highest under LDB (21.6 ± 2.02 mgr) and lowest in LDR larvae (13.6 ± 1.48 mgr). Yolk sac and oil globule absorption occurred more slowly in LDR and DD larvae, while LDB larvae developed their fin, teeth and swim bladder significantly earlier than the rest of the groups. DD larvae were unable to capture food and mortality was 100% by day post-hatching 18, while LDR larvae did not feed on rotifers, but fed on Artemia from day post-hatching 16 onwards. The best survival was obtained with the LL treatment, although significantly more problems with swim bladder development and lower jaw malformations were also identified in this group. In summary, these results highlight the key role of the light spectrum and photoperiod for European sea bass larvae, the best performance being achieved under the light conditions that best approached those of their natural aquatic environment (LDB). These findings should be considered when designing rearing protocols for larvae in aquaculture.

9 pages, 8 figures, 1 table, In the wild, water temperature cycles daily: it warms up after sunrise, and cools rapidly after sunset. Surprisingly, the impact of such daily thermocycles during the early development of fish remains neglected. We investigated the influence of constant vs daily thermocycles in zebrafish, from embryo development to sexual differentiation, by applying four temperature regimens: two constant (24°C and 28°C) and two daily thermocycles: 28:24°C, TC (thermophase coinciding with daytime, and cryophase coinciding with night-time) and 24:28°C, CT (opposite to TC) in a 12:12 h light:dark cycle (LD). Embryo development was temperature-dependent but enhanced at 28°C and TC. Hatching rhythms were diurnal (around 4 h after lights on), but temperature- and cycle-sensitive, since hatching occurred sooner at 28°C (48 hours post fertilization; hpf) while it was delayed at 24°C (96 hpf). Under TC, hatching occurred at 72 hpf, while under CT hatching displayed two peaks (at 70 hpf and 94 hpf). In constant light (LL) or darkness (DD), hatching rhythms persisted with tau close to 24 h, suggesting a clock-controlled >gating> mechanism. Under 28°C or TC, larvae showed the best performance (high growth and survival, and low malformations). The sex ratio was strongly influenced by temperature, as the proportion of females was higher in CT and TC (79 and 83% respectively), contrasting with 28°C and 24°C, which led to more males (83 and 76%). Ovarian aromatase (cyp19a) expression in females was highest in TC and CT (6.5 and 4.6 fold higher than at 28°C, respectively); while anti-mÿllerian hormone (amh) expression in males increased in testis at 24°C (3.6 fold higher compared to TC) and particularly at 28°C (14.3 fold increase). Taken together, these findings highlight the key role of environmental cycles during early development, which shaped the daily rhythms in fish embryo and larvae, and ultimately influenced sex differentiation, This research was funded by the Spanish Ministry of Economic Affairs and Competitiveness (MINECO) by projects “Circasole” AGL2010-22139-C03-01 granted to FJSV (http://www.mineco.gob.es), and AQUAGENOMICS (Consolider-Ingenio Program; CDS2007-0002) granted to FJSV and FP (http://www.idi.mineco.gob.es). Thanks are also due to COST ACTION FA0801 (Larvanet (http://www.larvanet.org)