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This study explored the effectiveness of green zinc oxide nanoparticles (ZnO-NPs) foliar spray on tomato growth and oxidative stress relief under drought conditions. Tomato plant subjected to four water regimes (100, 75, 50, and 25% FC), and in the same while seedlings were sprayed with 25, 50, and 100 mg/L green ZnO-NPs. The results showed that tomato growth parameters reduced significantly by increasing drought stress levels, while ZnO-NPs enhanced plant growth under all studied drought levels. Out of three ZnO-NPs concentrations tested, 25 and 50 mg/L ZnO-NPs proved to be the optimum treatments for alleviating drought stress. They increased shoot and root biomass compared to untreated controls. Application of 25 and 50 mg/L ZnO-NPs enhanced shoot dry weight by about 2–2.5-fold, respectively, under severe drought conditions (25%) compared to ZnO-NPs untreated plants. The application of 25 and 50 mg/L green ZnO-NPs decreased the drought-induced oxidative stress as indicated by the reduction in malondialdehyde and hydrogen peroxide concentrations compared to untreated controls. While 100 mg/L ZnO-NPs further increased oxidative stress. The beneficial effects of ZnO-NPs were evident in the plants’ defensive state, in which the concentration of ascorbic acid, free phenols, and the activity of superoxide dismutase, catalase, and ascorbate peroxidase were maintained at higher levels compared to NPs-untreated plants. At severe drought conditions, 25 mg/L ZnO-NPs induced SOD, CAT, and APX activity by about 3.99-, 3.23-, and 2.82-fold of their corresponding controls, respectively. Likewise, at 25% FC, SOD, CAT, and APX activity increased with 50 mg/L ZnO-NPs by about 4.58-, 3.57-, and 3.25-fold consecutively compared with their respective controls. Therefore, foliar use of green ZnO-NPs at lower concentrations might be suggested as an efficient way for enhancing tomato tolerance to drought stress.

Aiming determination of the effect of horse age and competitive season (May, July, September) on stress indicators in jumping horses in running track, research was performed on 14 studs (7 younger, and 7 older) trained and bred in the same conditions. The stress indicators (heartbeats, cortisol, glucose, and lactate concentrations in saliva) were measured or sampled before, during and at the end of the training - running track. The significance of the differences in stress indicators due to horse age regarding the competitive season was tested by t-test (PROC GLM, SAS/STAT). Based on conducted research it could be concluded that all analyzed stress indicators: heartbeats, and cortisol, glucose, and lactate concentrations in saliva, during the entire competitive season, were higher in younger (less experienced) comparing to older (more experienced) horses. Furthermore, all analyzed stress indicators were highest in July that is in the peak of competitive season. Since every physical activity causes a certain amount of stress, monitoring of stress indicators, especially heart- beats could be used for routine evaluation of horse preparedness for a particular activity.

Aiming to determine the variability in stress indicators due to horse age and competitive season (May, July, September) in jumping horses in parkour, research was performed on 14 studs (7 younger, and 7 older) trained and bred in the same conditions. The stress indicators (heartbeats, cortisol, glucose, and lactate concentrations in saliva) were measured or sampled before, during and at the end of the training - parkour jumping. The significance of the differences in stress indicators between the horse age classes regarding the competitive season was tested by Tukey’s test. Based on determined results it could be concluded that all stress indicators, during the entire competitive season, were higher in younger (less experienced) than in older (more experienced) horses. Furthermore, all stress indicators, with the exception of heartbeats, were highest in the peak of competitive season (July), while the lowest values of all stress indicators were determined at the end of competitive season (September). Monitoring of stress indicators, especially heartbeats, could be used for routine evaluation of horse preparedness for a particular activity.

In this article we introduce the concept of biological rhythms in fish welfare and critically discuss a neglected aspect: time-dependent issues. First we should consider that fish, like most living organisms, posses a clock that drives rhythmic biological functions. Therefore, fish stress responses are strongly affected by the time of stressor exposure (e.g. day/night) according to their daily pattern of behavior (diurnal/nocturnal). Furthermore, drugs affect fish differently depending of time of administration. For instance, commonly used substances such as anesthetics may have strikingly different effects depending on the time of day. MS-222 -the most widely used fish anesthetics- has fastest effects and higher toxicity when applied during daytime, but it is much less toxic at night. Surprisingly, no attention has been paid to this time-dependent factor when establishing dosages and protocols for fish anesthesia and euthanasia. In summary, there is a need to take into account properly the role of biological rhythms when discussing fish welfare issues and regulations by the Institutional Animal Care and Use Committee (IACUC). En este artículo se introduce el concepto de ritmos biológicos en el bienestar de peces, y se discute críticamente un tema olvidado: aspectos dependientes del tiempo. Primero debemos considerar que los peces, al igual que la mayoría de organismos vivos, poseen un reloj interno que dirige los ritmos biológicos. Por tanto, las respuestas al estrés de los peces están fuertemente afectadas por la hora de exposición al agente estresante (p.e. día/noche) en función de su patrón diario de comportamiento (diurno/nocturno). Además, los fármacos pueden afectar de forma diferente a los peces dependiendo de la hora de la administración. Por ejemplo, sustancias comúnmente usadas como los anestésicos pueden tener efectos llamativamente distintos dependiendo de la hora del día. El MS-222, el anestésico más ampliamente utilizado en peces, tiene efectos más rápidos y mayor toxicidad cuando es aplicado por el día, pero es mucho menos tóxico por la noche. Sorprendentemente, no se ha prestado atención a este factor temporal cuando se establecen dosis y protocolos para la anestesia o eutanasia de peces. En resumen, es necesario tener en cuenta adecuadamente el papel de los ritmos biológicos cuando se discute el bienestar de peces y su regulación por los comités de uso y cuidado de animales.

WOS: 000286814900006, PubMed ID: 20528621, Background: Body height is a versatile bio-indicator in that it reflects the quality of physical development. Fluctuating asymmetry, on the other hand, refers to small random deviations from perfect symmetry in bilaterally paired structures and is believed to reflect the ability of an organism to cope with genetic and environmental stresses during its development. Aim: This study sought to investigate the relationship between body height and fluctuating asymmetry in young adult males who display different height-development structures. Subject and methods: Height and eight bilateral non-facial traits were measured in a sample of 320 young male individuals from different socioeconomic backgrounds who display differences in height. Z-scores of each individual were calculated based on the age-range values indicated in the Center for Disease Control's (CDC) 2000 growth data of the US. Results: The five measurements demonstrating fluctuating asymmetry indicate that there is a significant increase in fluctuating asymmetry that parallels the decrease in body height. Developmental stability increases with the increasing body height. Conclusion: This finding implies that the stresses causing slower growth in body height might have negative effects also on fluctuating asymmetry.

NOTICE: this is the author’s version of a work that was accepted for publication in Journal of Plant Physiology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Plant Physiology, 167, 13 (2010) DOI http://dx.doi.org/10.1016/j.jplph.2010.02.011, The effects of the interaction between Mn and Cd on the growth of the white lupin (Lupinus albus), uptake of these metals, their accumulation, and effects on heavy metal stress indicators were studied under glasshouse conditions. Plants were grown with and without Mn and/or Cd for 4 weeks. The absence of Mn and Cd led to lipid peroxidation-induced loss of flavonoids and anthocyanins in the roots, reduced the size of the plant canopy, and led to the appearance of proteoid roots. Sensitivity to Cd in white lupin was enhanced by a low Mn supply, despite lower Cd uptake and accumulation (leaf Mn:Cd concentration ratio, This work was funded by the Spanish Ministry of Education and Science (project CTM2005-04809/TECNO)

Assessment of intrapopulation human health provides information concerning social structure, division of labor, and lifestyle. Differential health among the sexes can provide clues to social roles, resource acquisition and status within prehistoric populations. Windover (8Br246) is an Archaic mortuary pond located in eastern central Florida. Its occupation spans over 500 years and dates to 7000 years BP. Over 168 well-preserved individuals were excavated, providing a glimpse into life during Florida's Archaic. Through the application of the Western Hemisphere Health Index, we find that males within the group experienced better overall health than females. Males outscore females in quality of life, percent of maximum scores, stature, anemia, dental disease, and infection. Females out-score males in enamel hypoplasia and degenerative joint disease. Causative factors for observed differential health are examined and include activity levels, sexual division of labor, access to resources, and the physiological demands of childbearing.

In 2000–2001, an investigation was performed in two Sicilian mariculture sites (Pachino and Castellammare) to monitor physiological and biochemical parameters in sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) specimens farmed in off-shore sea cages. Plasma cortisol and glucose levels, tissue lactate concentration, haematocrit and haemoglobin content, lysozyme, haemolytic and haemagglutinating activities were determined. During the experiment, an increase in tissue lactate and plasma cortisol levels and a reduction in haemolytic and haemagglutinating titers, were recorded. Changes occurring in these haematological, immunological and biochemical values suggest that these parameters can be useful indicators in assessing the condition of chronic stress induced by mariculture operations.

10 pages, figures, and tables statistics., Cadmium effects on nodule structure and changes in organic and amino acids, proteins, nutrients and some stress indicators were studied in nodules of white lupin (Lupinus albus L., cv.Multolupa). Plants were grown hydroponically on perlite for 49 d with (18 μM) or without Cd in the nutrient solution. Cadmium-treated plants showed decreases in leaf chlorophyll and shoot sucrose concentrations, but sucrose did not change in nodules. Cadmium application produced alterations in nodule cortex and infected zone structure. Furthermore, Cd supply caused a marked decrease in P, K, leghemoglobin, N–amino compounds, malate, succinate and soluble protein in the nodules. Conversely, the levels of lipid peroxidation and total thiols increased strongly. Results obtained suggest that white lupin nodules are Cd sensitive, in spite of Cd sequestering by cell walls and thiols. The main phytotoxic effects of Cd on nodule structure and function were the occlusion with glycoprotein of intracellular spaces of nodule cortex, alterations in symbiosomes, enrichment in Cd of cell walls and oxidative stress. Glycoprotein accumulation and leghemoglobin depletion may be considered useful indicators of Cd stress in white lupin nodules., The authors are grateful to the Spanish MCyT (REN2001- 113-CO2-01 project) and Fundación Areces for their financial support and to Mr. A. Gil Aragón (SIDT, Junta de Extremadura) for supplying the seeds. The authors thank Dr. N.J. Brewin for providing the MAC236. The technical assistance of C. de Mesa and F. Pinto from CSIC is greatly acknowledged. The nutrients were analysed in the ICP/MS laboratory from the SIDI-UAM with the assistance of I. Rivas. The amino acid analysis was possible thanks to Prof. M. Ugarte and the technical assistance of P. Sanz (CBM).We are also grateful to P. Martínez for her technical assistance with plant growth.

7 pages, and figures, and tables statistics., White lupin plants (Lupinus albus L., cv. Multolupa) were grown hydroponically on perlite with different Cd concentrations in the nutrient solution (μM): 0, 18 and 45. Changes in growth, nodulation, nutrient concentrations, nutrient uptake and distribution, Cd bound to cell wall and some Cd stress indicators were studied in roots and shoots (leaves plus stem) of 35-d-old plants as a result of Cd uptake. A significant decrease in both root and shoot dry weight was found only when plants were grown on 45 μM Cd, whereas nodulation and total N content decreased for both Cd levels. White lupin plant retained up to 88% of total Cd in the roots, showing some capacity of Cd translocation to the upper parts, but an important fraction of Cd was bound to the cell walls. Cadmium addition reduced P, K, Fe, Mn and Zn concentrations in the shoot and Mn in the root. Despite the reduction in Mn concentration, Mn level in Cd-treated plants remained within normality, probably because white lupin is a Mn accumulator. In Cd-treated plants, the level of lipid peroxidation remained unmodified, whereas total thiols showed a pronounced increase in roots. Results obtained suggest that white lupin has developed several strategies of defence against Cd, as a high retention of Cd by cell walls and complexation by thiol groups, both contributing to diminish the level of free Cd. Moreover, the high Mn content of white lupin could contribute to the prevention of Cd damage on photosynthesis, since chlorosis was not found., Authors are indebted to the Spanish DGICyT for its financial support through project PB98-0114-CO2-02. Bacterial strains and seeds were a kind gift from Dra. Fernández-Pascual (CSIC) and from Andres Gil Aragón (SIDT, Junta de Extremadura), respectively. We are grateful to Pilar Martínez for her technical assistance.