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Environmental changes alter the selective pressures acting on species, leading to different responses. Morphological variation can increase a species' ability to occupy different habitats, persist in uncertain environments and stabilize its interactions with other species. We examined the morphological variation (wings, thorax and tibiae) of Eulaema nigrita , a widespread species of euglossine bee (Euglossini, Apidae), from populations at 13 localities in Brazil. We found significant variation in most attributes among all populations, high variation in morphological attributes within populations and seasonality of temperature as the most important factor structuring the morphological variation. Our results provide evidence on how the variation in morphological attributes allows us to more accurately explore the responses of populations to changes in environmental conditions. [ABSTRACT FROM AUTHOR]

Erioscelis emarginata is a species of pollinator scarab beetle whose adults are predominantly associated with night-blooming aroid inflorescences (Araceae) of the Neotropical genus Thaumat ophyllum , towards which they are attracted by volatile organic compounds (VOCs). It is assumed that olfactory preferences towards species-specific floral VOCs emitted by different plant hosts, as well as geographical segregation of natural populations of E. emarginata , might reinforce their reproductive isolation and differentiation, but external morphological dissimilarities between them are not evident. In the present work, body shapes of geographically isolated populations of E. emarginata associated with different species of Thaumat ophyllum were compared using landmark-based geometric morphometrics. A total of 86 adult specimens of E. emarginata were analyzed, collected in inflorescences of Thaumat ophyllum spp. at four locations in Brazil distant 333–912 km from one another. Eighteen landmarks and semi-landmarks were digitized to capture the shapes of the elytra and pronotum separately, and landmarks configurations were compared through Canonical Variates and pairwise Discriminant Function Analyses. There were significant shape differences between specimens from the four different populations of E. emarginata (p < 0.05) in all paired comparisons, for both the shape of the elytra and pronotum and correct classification levels were high for most pairwise comparisons. Further investigations on the morphological variation across these populations and assessments of the specificity of their olfactory-oriented relationship with host plants are important next steps in understanding the full scenario of the segregation and diversification of E. emarginata. In addition, a lectotype male of Apogonia emarginata (ZIN) was designated to fix the identity of E. emarginata. [ABSTRACT FROM AUTHOR]

Nowadays, there is an increased demand for micro-products and micro-components in many industry sectors therefore development of advanced manufacturing technologies and metrological instrumentation in this range, have thus become a critical issue and an engineering challenge. If a product cannot be measured, although it might be manufactured, it would not be possible to analyse its design in order to improve its functionality. Electroforming could be defined as the highly specialized use of electrodeposition for the manufacturing of metal parts. Due to progress in materials, processes and equipment, electroforming has shown considerable development. Consequently, electroforming is increasingly combined with other micro-manufacturing technologies, giving rise to other processes such as LIGA and UV-LIGA. Thanks to the accumulated experience of Fabricación Integrada y Avanzada research group, of the University of Las Palmas de Gran Canaria in the electroforming process focused on macro-scale, as well as specific equipment available, this paper aims to analyse the potential of electroforming process for micro-injection mould manufacturing. [ABSTRACT FROM AUTHOR]

This study was undertaken to elucidate the effect of the essential oil from Alpinia speciosa (EOAs) on cardiac contractility and the underlying mechanisms. The essential oil was obtained from Alpinia speciosa leaves and flowers and the oil was analyzed by GC-MS method. Chemical analysis revealed the presence of at least 18 components. Terpinen-4-ol and 1,8-cineole corresponded to 38% and 18% of the crude oil, respectively. The experiments were conducted on spontaneously-beating right atria and on electrically stimulated left atria isolated from adult rats. The effect of EOAs on the isometric contractions and cardiac frequency in vitro was examined. EOAs decreased rat left atrial force of contraction with an EC(50) of 292.2±75.7[mu]g/ml. Nifedipine, a well known L-type Ca(2+) blocker, inhibited in a concentration-dependent manner left atrial force of contraction with an EC(50) of 12.1±3.5[mu]g/ml. Sinus rhythm was diminished by EOAs with an EC(50) of 595.4±56.2[mu]g/ml. Whole-cell L-type Ca(2+) currents were recorded by using the patch-clamp technique. EOAs at 25[mu]g/ml decreased I(Ca,L) by 32.6±9.2% and at 250[mu]g/ml it decreased by 89.3±7.4%. Thus, inhibition of L-type Ca(2+) channels is involved in the cardiodepressive effect elicited by the essential oil of Alpinia speciosa in rat heart. [ABSTRACT FROM AUTHOR]

Abstract: This study was undertaken to elucidate the effect of the essential oil from Alpinia speciosa (EOAs) on cardiac contractility and the underlying mechanisms. The essential oil was obtained from Alpinia speciosa leaves and flowers and the oil was analyzed by GC–MS method. Chemical analysis revealed the presence of at least 18 components. Terpinen-4-ol and 1,8-cineole corresponded to 38% and 18% of the crude oil, respectively. The experiments were conducted on spontaneously-beating right atria and on electrically stimulated left atria isolated from adult rats. The effect of EOAs on the isometric contractions and cardiac frequency in vitro was examined. EOAs decreased rat left atrial force of contraction with an EC50 of 292.2±75.7μg/ml. Nifedipine, a well known L-type Ca2+ blocker, inhibited in a concentration-dependent manner left atrial force of contraction with an EC50 of 12.1±3.5μg/ml. Sinus rhythm was diminished by EOAs with an EC50 of 595.4±56.2μg/ml. Whole-cell L-type Ca2+ currents were recorded by using the patch-clamp technique. EOAs at 25μg/ml decreased I Ca,L by 32.6±9.2% and at 250μg/ml it decreased by 89.3±7.4%. Thus, inhibition of L-type Ca2+ channels is involved in the cardiodepressive effect elicited by the essential oil of Alpinia speciosa in rat heart. [Copyright &y& Elsevier]

Abstract: Aims: Thiamine is an important cofactor present in many biochemical reactions, and its deprivation can lead to heart dysfunction. Little is known about the influence of thiamine deprivation on the electrophysiological behavior of the isolated heart cells and information about thiamine deficiency in heart morphology is controversial. Thus, we decided to investigate the major repolarizing conductances and their influence in the action potential (AP) waveform as well as the changes in the heart structure in a set of thiamine deficiency in rats. Main methods: Using the patch-clamp technique, we investigated inward (I K1) and outward K+ currents (I to), T-type and L-type Ca2+ currents and APs. To evaluate heart morphology we used hematoxylin and eosin in transversal heart sections. Key findings: Thiamine deficiency caused a marked decrease in left ventricle thickness, cardiomyocyte number, cell length and width, and membrane capacitance. When evaluating I to we did not find difference in current amplitude; however an acceleration of I to inactivation was observed. I K1 showed a reduction in the amplitude and slope conductance, which implicated a less negative resting membrane potential in cardiac myocytes isolated from thiamine-deficient rats. We did not find any difference in L-type Ca2+ current density. T-type Ca2+ current was not observed. In addition, we did not observe significant changes in AP repolarization. Significance: Based on our study we can conclude that thiamine deficiency causes heart hypotrophy and not heart hypertrophy. Moreover, we provided evidence that there is no major electrical remodeling during thiamine deficiency, a feature of heart failure models. [Copyright &y& Elsevier]

Abstract: A probabilistic framework is presented to select the design significant wave height and design transverse rotation for typical barges used in the Gulf of Mexico for marine transportation of structural elements and/or systems. The selection of design transverse rotation is based on optimization procedure that trade-off between the performance of the barge subjected to a meteorological-oceanographic (metocean) hazard along the route and losses by structural damage. For this purpose probabilistic models to estimate the metocean hazard for marine transportation are shown. Afterwards, the design rotation is linked to the design of significant wave height and to the return period associated with such wave conditions. The formulation is applied to an offshore transportation route in the Gulf of Mexico. [Copyright &y& Elsevier]

The article discusses the results of a study which compared the postural control of small for gestational age (SGA) and appropriate for gestational age (AGA) infants born at term. Results show that the postural control of the SGA group was influenced by the gestational age and 5th minute Apgar in the third month, and by maternal occupation in the sixth month. It was found that the postural control of the SGA group was influenced by biological and environmental factors.

Given the importance of Listeria monocytogenes as a risk factor in meat and poultry products, there is a need to evaluate the relative robustness of predictive growth models applied to meat products. The U.S. Department of Agriculture-Agricultural Research Service Pathogen Modeling Program is a tool widely used by the food industry to estimate pathogen growth, survival, and inactivation in food. However, the robustness of the Pathogen Modeling Program broth-based L. monocytogenes growth model in meat and poultry application has not, to our knowledge, been specifically evaluated. In the present study, this model was evaluated against independent data in terms of predicted microbial counts and covered a range of conditions inside and outside the original model domain. The robustness index was calculated as the ratio of the standard error of prediction (root mean square error of the model against an independent data set not used to create the model) to the standard error of calibration (root mean square error of the model against the data set used to create the model). Inside the calibration domain of the Pathogen Modeling Program, the best robustness index for application to meat products was 0.37; the worst was 3.96. Outside the domain, the best robustness index was 0.40, and the worst was 1.22. Product type influenced the robustness index values (P < 0.01). In general, the results indicated that broth-based predictive models should be validated against independent data in the domain of interest; otherwise, significant predictive errors can occur. [ABSTRACT FROM AUTHOR]

Objectives: There is currently no consensus on how success should be defined after medical management of first-trimester missed abortion. The aim of this study was to determine the transvaginal ultrasound criterion associated with highest success rate and, at the same time, lowest long-term complications. Design: Prospective observational study of consecutively enrolled patients. Setting: A tertiary care university hospital in northern Portugal. Participants: Forty-four women submitted to medical management of first-trimester missed abortion using a regimen of vaginal misoprostol, with histologically confirmed conception products passed vaginally. A transvaginal ultrasound scan was performed by an experienced sonographer in the morning after treatment, to characterise uterine content. Patients were provided with a chart for daily registration of axillary temperature, vaginal bleeding and lower abdominal pain. Transvaginal ultrasound was repeated 2-3 weeks later, and again after the following menses. Main Outcome Measures: Success rates of medical management when post-treatment transvaginal ultrasound criteria for subsequent expectant management were: absence of intra-uterine sac, largest anteroposterior diameter of hyperechogenic content, and maximum area of hyperechogenic intra-uterine content in a sagittal view. Self-reported duration of vaginal bleeding and abdominal pain after medical treatment. Results: Success rate was 86% (38/44) when absence of gestational sac on the 12 h transvaginal ultrasound was used as the main criterion for subsequent expectant management and there was no need for further intervention. The success rate using the ultrasound criterion anteroposterior diameter < or = 15 mm was 51% (22/43), and with maximum sagittal plane area under 7.5 cm(2), 72% (31/43). Mean duration of vaginal haemorrhage was 9 days (minimum 2 days, maximum 14 days) and of lower abdominal pain 6 days (minimum 0 days, maximum 14 days). No patient recorded an axillary temperature exceeding 37 degrees C. No apparent relationship between the size of ultrasound-estimated intra-uterine content and duration of symptoms was observed. Conclusions: Absence of gestational sac on transvaginal ultrasound should be the criterion used to document success after medical management of first-trimester missed abortion, as it is associated with the highest short and long-term success rates, as well as mild and self-limited symptoms in the days following treatment. [ABSTRACT FROM AUTHOR]

• The fruits of Bactris guineensis are targeted for broad scale production for the Colombian market. • Minute pollen-feeding beetle species are the exclusive pollinators of native populations. • Arrival of pollinators is synchronized with brief events of stigma receptivity and pollen shedding. • Despite strict xenogamy, reproductive success over 75% is attributed to high pollinator efficiency. Regardless of the ecological and economical importance of palms, their pollination strategies and the identities of their true pollinators are still contentious subjects. Bactris guineensis grows in open areas in lowland Caribbean Colombia. Its fruits have long been an important component of local economy and are now targeted for broader scale production for the Colombian market. We explored details of the reproductive biology of B. guineensis in its natural environment to understand the various elements of pollen flow dynamics that ensure optimal fruit yield. During two consecutive years, we investigated the phenology, floral biology and pollination ecology of a wild population of B. guineensis in the department of Sucre, northern Colombia. Monthly production of buds, inflorescences and ripe infructescences were quantified. Pollen carrying capacity, efficiency and fidelity of anthophilous insect species associated with B. guineensis were calculated and used to define their role as effective pollinators. Bactris guineensis is protogynous and exhibits ephemeral nocturnal anthesis. In spite of strict xenogamy the average reproductive success was over 75%, attributed to high pollen vector efficiency. Twenty-seven insect species representing three orders were recorded as floral visitors, but the only effective pollinators were minute flower weevils and sap beetles. At the beginning of the female phase of anthesis, when pistillate flowers are receptive, inflorescences of B. guineensis warm up to over 12 °C above ambient air and emit a balsamic scent, attracting swarms of several hundred to thousands of beetles loaded with pollen. A second, shorter-lasting floral heating event takes place by dusk in the following day (or the male phase), which culminates with pollen shedding of staminate flowers and departure of the pollinators. Anthesis events that are highly synchronized with activity patterns of specialized scent-oriented pollinators ensure the high reproductive success of B. guineensis at our study site. Plans for large scale production should prioritize insect-friendly practices and investigation on the role of volatile floral kairomones for pollinator attraction. [ABSTRACT FROM AUTHOR]

Background The liver may be injured in situations where it is submitted to ischemia, such as partial hepatectomy and liver transplantation. In all cases, ischemia is followed by reperfusion and, although it is essential for the reestablishment of tissue function, reperfusion may cause greater damage than ischemia, an injury characterized as ischemia-reperfusion (I/R) damage. The aim of this work was to analyze the effect of ischemic preconditioning with the use of methylene blue (MB; 15 mg/kg) 5 or 15 minutes before I/R (IRMB5′ and IRMB15′, respectively) on the hepatic injury occurring after I/R. Methods Twenty-eight male Wistar rats were used, and liver samples submitted to partial ischemia (IR) or not (NI) were obtained from the same animal. The samples were divided into 7 groups. Data were analyzed statistically by means of the nonparametric Mann-Whitney test and Wilcoxon Matched test, with the level of significance set at 5% ( P < .05). Results The rate of oxygen consumption by state 3 mitochondria was inhibited in all ischemic groups compared with the sham group (SH vs IR: P = .0052; SH vs IRMB5′: P = .0006; SH vs IRMB15′: P = .0048), which did not occur in the nonischemic contralateral portion of the same liver (SH vs NI: P = .7652; SH vs NIMB5′: P = .059; SH vs NIMB15′: P = .3153). The inhibition of the rate of oxygen consumption by state 3 mitochondria was maintained in the presence of MB (IR vs IRMB5′: P = .4563; IR vs IRMB15′: P = .9021). The respiratory control ratio was reduced in all ischemic groups compared with the sham group, owing to the inhibition of oxygen consumption in state 3 (SH vs IR: P = .0151; SH vs IRMB5′: P = .005; SH vs IRMB15′: P = .0007). Conclusions Methylene blue had no effect on the mitochondrial respiratory parameters studied, but was able to reduce lipid peroxidation, preventing the production of reactive oxygen species (SH vs IRMB15′: P = .0210). [ABSTRACT FROM AUTHOR]

The objectives of this study were to describe alterations that age and dietary inclusion of direct-fed microbial (DFM) Bacillus subtilis (BS) and a specific essential oil (EO) blend (carvacrol, cinnamaldehyde, cineol, and pepper extract) causes in the activity of digestive enzymes (maltase: MALT; aminopeptidase-N: APN; intestinal alkaline phosphate: IAP) and expression patterns of genes related to transport (oligopeptide transporter gene: SLC15A1; Na+-dependent glucose and galactose transporter gene: SLC5A1; Na+-independent glucose, galactose, and fructose transporter gene: SLC2A2; ATPase, Na+/K+ transporting gene: ATP1A1) and digestion (aminopeptidase-N gene: ANPEP; maltase-glucoamylase gene: MGAM; Sucrase-isomaltase gene: SI) of carbohydrates and proteins in the small intestine of broilers. Also, the objective was to analyze if growth performance of broilers is affected by supplementation (BS and EO blend). Day-old male broiler chicks (n = 1,320) were assigned to 5 treatments. Diets included a basal diet (BD) as a negative control (CON); experimental diets were BD + BS; BD + BS + EO; BD + EO; BD + antibiotic growth promoter (AGP) avilamycin was the positive control. Performance was evaluated between 1 to 42 d. Transcript abundance of transport-related genes and digestion-related genes were assayed by RT-qPCR and determined at d 7, 21, and 42. MALT-, APN-, and IAP-specific activities were determined at d 7, 21, and 42. Broilers fed BS had greater SLC15A1 mRNA abundance compared to CON, while EO and AGP were related to higher activities of IAP and APN. Analysis over time revealed higher abundance of MGAM, SLC2A2, SLC15A1, SLC5A1 and SI mRNA at d 42 when compared to d 7. Activity of IAP decreased after d 7 and activity of MALT increased with age. The current study suggests that age had effect over carbohydrate and protein transport and carbohydrate digestion. The supplementation of BS DFM hade evident effect over protein transport and that the use of EO in the diet enhanced the activities of carbohydrate and protein digestion, reflecting improvement in digestive and transport physiology of birds. Changes performed by BS DFM and EO did not favor performance. [ABSTRACT FROM AUTHOR]

A previous study showed that a chitosan mouthwash would be a valid alternative to current mouthwashes as it demonstrated, in vitro, significantly higher antibiofilm activity than two commercial mouthwashes. As such, the aim of this work was to verify the safety of the developed product and to validate, in vivo, the biological activity ascertained in vitro. Chitosan mouthwash safety was evaluated through Ames, MTT and V79 chromosomal aberration assay while antimicrobial activity was evaluated through in vivo assays. The results showed that the chitosan mouthwash was safe, presenting lower cytotoxicity than a commercial mouthwash, and that it effectively reduced viable counts of Streptococcus spp. and Enterococcus spp. by ca. 5.5 log of CFU. Furthermore, in direct comparison with a commercial mouthwash the chitosan mouthwash possessed significantly higher antimicrobial activity. The conjunction of these results proves that the chitosan mouthwash is a safe, effective, natural alternative to the existent chemical mouthwashes. [ABSTRACT FROM AUTHOR]