The Scimitar Precooled Mach 5 Engine

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Cryopreservation of Gametes and Larvae of the Eastern Oyster Crassostrea Virginica.

Storage of gametes and larvae offers benefits for research and commercial oyster production and should be applicable in the hatchery at a commercial scale. We optimized refrigerated storage of eastern oyster sperm. Significant differences were found in the motility of sperm suspended in artificial sea water (ASW) of different osmotic pressures (P \u3c 0.001). The highest motility was found in undiluted sperm and the lowest in 1:31 dilution. The greatest larval survival at 12 h (48%) was obtained with sperm diluted in calcium-free Hanks\u27 balanced salt solution (C-F HBSS). Thus, for storage of longer than 1 d, it is best to leave samples undiluted. However, when sperm samples are diluted, it is best to maintain high sperm concentrations and to use C-F HBSS as an extender. Samples were frozen at -2.5°C/min, held for 5 min at -30°C, and plunged in liquid nitrogen using 10% propylene glycol (PG) as the cryoprotectant for sperm and 10% or 15% PG for trochophore larvae. Motility and fertilizing ability of thawed sperm were affected by cryoprotectant concentration and thawing temperature (P = 0.0001). Larval survival was affected by the concentration of larvae per straw (P = 0.0011). Frozen samples were transported to an oyster hatchery at Grand Isle, Louisiana. After 4 months, 1,000 oysters from the control group, 230 oysters produced from thawed sperm, and 850 oysters from thawed larvae were found. Oysters produced from thawed larvae developed normally in the hatchery, demonstrating opportunities for use of cryopreservation in research and aquaculture. Flow cytometry with the fluorescent dyes Sybr-14 and propidium iodide (PI) was used to assess membrane damage of thawed sperm, and rhodamine 123 and PI were used to assess mitochondrial function. Preliminary studies of cryopreservation of oyster eggs were performed. Fluorescein diacetate (FDA) was used to identify viable eggs. Dimethyl sulfoxide (0.88 M and 1.75 M) and sucrose (0.12 M and 0.25 M) were the least toxic cryoprotectants evaluated. The cooling rate yielding least damage to eggs was -1.5°C per min. However, only an average of 14 eggs (out of 200) were stained with FDA in thawed samples and none were fertilizable

Experimental analysis on the effects of DC arc discharges at various flow regimes

This paper addresses the control of the boundary layer on a compression ramp by means of DC electrical arc discharges. The development and realization of the control system are first described and then assessed in the wind tunnel. The objective of the research was to control the supersonic flow using the minimum amount of energy. The array of electrodes was located at the base of a ramp, where a low momentum flow develops. The electrical discharge was generated by a custom designed electronic facility based on high-voltage ignition coils. The slanted tungsten electrodes were insulated by mounting them in a ceramic support. The discharge evolution was studied through high-speed flow visualizations, while electrical measurements at the high-voltage section of the circuitry allowed to estimate the energy release. The development of a high-speed short exposure Schlieren imaging technique, based on a very short duration laser pulse illumination and a double shot CCD camera, allowed to observe the macroscopic effects associated with the arc establishment between the electrodes (glow, sound wave and heat release). Due to the long residence time, the thermal perturbation spread along the streamwise direction. Cross correlation of Schlieren images with short time separation revealed that in supersonic conditions, the discharges led to an overall acceleration of the flow field underneath the oblique shock wave

Model selection for spatiotemporal modeling of early childhood sub-cortical development

Spatiotemporal shape models capture the dynamics of shape change over time and are an essential tool for monitoring and measuring anatomical growth or degeneration. In this paper we evaluate non-parametric shape regression on the challenging problem of modeling early childhood sub-cortical development starting from birth. Due to the flexibility of the model, it can be challenging to choose parameters which lead to a good model fit yet does not overfit. We systematically test a variety of parameter settings to evaluate model fit as well as the sensitivity of the method to specific parameters, and we explore the impact of missing data on model estimation

Utilidad de Trigonella foenum-graecum en la leche materna como medicina alternativa y complementaria

The purpose of the bibliographic review article focuses on the main objective of analyzing information about the usefulness of Trigonella foenum-graecum “fenugreek” in breast milk as an alternative and complementary medicine. It is a descriptive, non-experimental study, for which 9 articles with a publication time of no more than 15 years old were selected. The results found for the usefulness of Trigonella foenum-graecum in breast milk were that, increases its production up from 20 to 100% in volume, increases prolactin levels and the weight of the infant of mothers who consume Trigonella foenum -graecum for a period of one month. It was concluded that Trigonella foenum-graecum is useful in breast milk mainly by increasing its production, being able to be used as part of alternative and complementary medicine due to its safe use in mothers who breastfeed their babies; it also increases prolactin levels and helps increase the infant’s weight.El propósito del artículo de revisión bibliográfica se centra en el objetivo principal de analizar información sobre la utilidad de Trigonella foenum-graecum “fenogreco” en la leche materna como medicina alternativa y complementaria. Es un estudio descriptivo no experimental, para lo cual se seleccionó 9 artículos con un tiempo de publicación no mayor a 15 años de antigüedad. Los resultados encontrados para la utilidad de Trigonella foenumgraecum en la leche materna fueron que, aumenta su producción hasta desde un 20 hasta un 100% en volumen, aumenta los niveles de prolactina he incrementa el peso del lactante de las madres que consumen Trigonella foenum-graecum por el lapso de un mes. Se concluyó que Trigonella foenum-graecum si tiene utilidad en la leche materna principalmente aumentando su producción, pudiéndose emplear como parte de la medicina alternativa y complementaria por su uso inocuo en las madres que den de lactar a sus bebés; también aumenta los niveles de prolactina y ayuda a incrementar el peso del lactante

A simple method for short-term storage and transportation of spermatophores of Pacific white shrimp (Litopenaeus vannamei )

The development of a shipping method for spermatophores of the white shrimp Litopenaeus vannamei would open new opportunities for sharing and improving genetic resources of shrimp worldwide. Seventy spermatophores were collected daily for 5 days (a total of 350 spermatophores from 175 shrimp), packed in microcentrifuge tubes containing 100 ?L of an extender solution, and placed in a Styrofoam box supplied with a thermal insulating layer and refrigerant pack to keep the samples cooled at ~14°C. Shipment of samples took ~26 hours. At arrival, spermatophores were randomly sampled either as soon as the box arrived (~27 h, Group A) or five hours later (~32 h, Group B) to assess sperm viability. Spermatozoal morphology was evaluated by microscopy (100 cells per shrimp). Cells without spikes or irregular in shape were recorded as abnormal; otherwise cell morphology was recorded as normal. Spermatozoal viability was assessed by flow cytometry, whereby three populations were identified: (1) cells with intact cytoplasmatic membrane (viable), (2) cells with disrupted membrane (non-viable), and (3) cells in transition, changing from intact to disrupted membrane (transitional). Significant differences were found in spermatozoal morphology between group A and B (p = 0.002), with the highest percentage of normal spermatozoa (92 + 15%) found in Group A. No significant differences were found in viable (p = 0.723) and transitional spermatophore populations (p = 0.595) assessed by flow cytometry. Non-viable populations increased with time in storage (p = 0.039). The highest percentage of non-viable cells (81 + 7%) was obtained in Group B. These results indicate that spermatophores can be cooled and transported to distant locations maintaining normal morphology and viability. These indirect quality indicators suggest that spermatozoa may be used for different purposes, including artificial insemination.The development of a shipping method for spermatophores of the white shrimp Litopenaeus vannamei would open new opportunities for sharing and improving genetic resources of shrimp worldwide. Seventy spermatophores were collected daily for 5 days (a total of 350 spermatophores from 175 shrimp), packed in microcentrifuge tubes containing 100 ?L of an extender solution, and placed in a Styrofoam box supplied with a thermal insulating layer and refrigerant pack to keep the samples cooled at ~14°C. Shipment of samples took ~26 hours. At arrival, spermatophores were randomly sampled either as soon as the box arrived (~27 h, Group A) or five hours later (~32 h, Group B) to assess sperm viability. Spermatozoal morphology was evaluated by microscopy (100 cells per shrimp). Cells without spikes or irregular in shape were recorded as abnormal; otherwise cell morphology was recorded as normal. Spermatozoal viability was assessed by flow cytometry, whereby three populations were identified: (1) cells with intact cytoplasmatic membrane (viable), (2) cells with disrupted membrane (non-viable), and (3) cells in transition, changing from intact to disrupted membrane (transitional). Significant differences were found in spermatozoal morphology between group A and B (p = 0.002), with the highest percentage of normal spermatozoa (92 + 15%) found in Group A. No significant differences were found in viable (p = 0.723) and transitional spermatophore populations (p = 0.595) assessed by flow cytometry. Non-viable populations increased with time in storage (p = 0.039). The highest percentage of non-viable cells (81 + 7%) was obtained in Group B. These results indicate that spermatophores can be cooled and transported to distant locations maintaining normal morphology and viability. These indirect quality indicators suggest that spermatozoa may be used for different purposes, including artificial insemination

Co-Ingestion of Dietary Nitrate and Ascorbic Acid on Nitric Oxide Biomarkers and The Oral Microbiome in Sedentary Hispanic Women

Nitric oxide bioavailability increases following nitrate supplementation wherein oral microbiota facilitate the metabolism and absorption of nitrate. However, few studies have examined if co-ingestion of nitrate with antioxidants can further elevate nitric oxide bioavailability. Moreover, our understanding on how the oral microbiome responds to nitrate supplementation is limited, especially in women. PURPOSE: To examine the effects of ingesting dietary nitrate and ascorbic acid independently and concurrently on markers of nitric oxide bioavailability and oral microbiota species. METHODS: Twelve sedentary women of Hispanic descent (mean ± SD: age 20 ± 1 years; body mass 74 ± 15 kg; height 1.62 ± 0.09 m) consumed nitrate-rich beetroot juice (BR), nitrate-depleted beetroot juice (PL), ascorbic acid (AA), and crystal light (CRY) in four conditions: BR combined with AA (BR+AA); BR only (BR+CRY); AA only (PL+AA); and placebo-control (PL+CRY). Supplements were ingested 2.5 hours prior to a resting blood draw and buccal swab sample. Plasma [nitrate] and [nitrite] were analyzed using gas phase chemiluminescence. Buccal swab samples were used for DNA extraction and isolation. DNA was amplified using polymerase chain reaction (PCR) targeting the V3 - V4 region of the 16S rRNA gene. Following index PCR, amplicons were pooled and sequenced using the iSeq Illumina NGS sequencer. Reads were clustered into amplicon sequence variants and analyzed for alpha and beta diversity and relative abundance. RESULTS: BR increased plasma [nitrate] (BR+AA: 641 ± 252 vs. BR+CRY: 528 ± 307 vs. PL+AA: 35 ± 10 vs. PL+CRY: 35 ± 12 µM, P \u3c 0.001) and plasma [nitrite] (BR+AA: 710 ± 336 vs. BR+CRY: 578 ± 428 vs. PL+AA: 209 ± 88 vs. PL+CRY: 198 ± 82 nM, P \u3c 0.001) with no differences within BR and PL conditions. Alpha and beta diversity, and the relative abundance of higher and lower taxonomic levels were not significantly different between all conditions (P \u3e 0.05) CONCLUSION: Concurrent nitrate and AA supplementation did not elicit additional increases to nitric oxide compared to nitrate ingestion alone. Acute beetroot juice and ascorbic acid were ineffective at modulating oral microbial composition. Further research is required to understand the impact of supplementation regimen and population on the physiological effects of dietary nitrate

ZrO2-SBA-15 catalysts for the one-pot cascade synthesis of GVL from furfural

Controlling the thickness of zirconia monolayers coated over SBA-15 offers an effective way to tune catalytic performance for the acid-mediated and hydrogen transfer (Meerwein Ponndorf Verley, MPV) cascade transformation of furfural to γ-valerolactone. Complementary mechanistic and kinetic modelling establishes the existence of the two distinct zirconium active species (weak and strong acid sites), whose balancing enables optimisation of the cascade and hence maximal γ-valerolactone (GVL) production

EFECTO DE DIFERENTES SISTEMAS DE ALIMENTACIÓN SOBRE EL RENDIMIENTO Y CORTES DE LA RES EN NOVILLOS

El estudio fue realizado con el objetivo de determinar el rendimiento de la res en bovinos de carne, el corte de sus partes y músculos como el peceto (Semitendinosus) y el lomito (Psoas major) en animales mantenidos en confinamiento y pastoreo más suplementación. Fueron utilizados 36 cabezas, provenientes de los distintos sistemas de terminación, 18 para cada tratamiento. La terminación de los animales fue determinada por medio del espesor de la grasa subcutánea medido por ultrasonido a nivel de la 12ª costilla. El tratamiento 1, consistió en animales provenientes de un sistema de alimentación en confinamiento, alimentados a base de ensilado de maíz, grano de maíz, sojilla, sal mineral y heno de Colonial; el tratamiento 2, estuvo formado por animales provenientes de un sistema de pastoreo rotativo intensivo, sobre una pastura de Panicum maximum cv. Mombaza, con una suplementación invernal de sojilla y maíz. Los datos obtenidos fueron sometidos a análisis de varianza al 5 % y las medias se compararon a través de la prueba "T". Además, se realizaron análisis de correlación entre los parámetros estudiados. Resultando que entre ambos tratamientos no se encontraron diferencias en el peso de salida y peso de faena, mientras que en el desbaste existió diferencia superior a favor del confinamiento. El rendimiento de la res como porcentaje del peso vivo sin desbaste fue estadísticamente superior en el pastoreo más suplementación, mientras que en el peso de la res y como porcentaje del peso vivo con desbaste no arrojaron diferencias. En cuanto a los cortes de la res como el delantero en peso y como porcentaje del peso vivo sin desbaste fueron superiores en el pastoreo más suplementación. Mientas que el confinamiento resultó superior el costillar como porcentaje del peso vivo con desbaste, no se encontró diferencia en los otros parámetros evaluados. Los cortes de músculo no presentaron diferencias estadísticas en ambos tratamientos