Investigation of the C—CN Bond Activation of Fluorinated Benzonitriles with [Ni(dmpe)] and Dft Benchmarking Study with [Ni(dippe)]

Carbon-carbon bond activation has become a rapidly growing area of research due to its extensive range of applications. Despite the significant progress that has been made in this field, the cleavage of kinetically inert and thermodynamically stable C—C σ-bonds under mild homogeneous conditions remains a challenge. The activation is primarily limited to systems in which either relief of strain or aromatization serves as a driving force. A notable exception to this is the oxidative addition of unstrained C—CN bonds of nitriles. In this study, we are looking at the effect of fluoro substituents. We hypothesized that the number of ortho-F substituents would affect the product stability, rather than the total number of fluoro substituents. The benzonitrile substrates investigated are the 2-F, 3-F, 4-F, 2,6-F2, and 3,5-F2benzonitriles. The effects on the C—CN bond activation reaction of the fluorinated benzonitriles were investigated using [Ni(dmpe)] as a model for [Ni(dippe)] with DFT calculations. Both experimental and DFT calculation results have shown that there is a very good correlation between the stability of the C—CN bond activation products and the number of o-fluoro substituents. Although the C—C bond activation barrier is relatively constant with a slightly higher barrier for 2,6-F2 substrate due to steric hindrance, the activation barriers for the C—C bond elimination show a good correlation with the number of o-F substituents. For the future work, we will continue the DFT analysis with [Ni(dippe)] using the results from our benchmarking study

Ermakov Systems with Multiplicative Noise

Using the Euler-Maruyama numerical method, we present calculations of the Ermakov-Lewis invariant and the dynamic, geometric, and total phases for several cases of stochastic parametric oscillators, including the simplest case of the stochastic harmonic oscillator. The results are compared with the corresponding numerical noiseless cases to evaluate the effect of the noise. Besides, the noiseless cases are analytic and their analytic solutions are briefly presented. The Ermakov-Lewis invariant is not affected by the multiplicative noise in the three particular examples presented in this work, whereas there is a shift effect in the case of the phasesComment: 12 pages, 4 figures, 22 reference

Red cell trapping and postischemic renal blood flow. Differences between the cortex, outer and inner medulla

Red cell trapping and postischemic renal blood flow. Differences between the cortex, outer and inner medulla. The distribution of blood flow in the rat kidney after 60 minutes of renal ischemia was studied by single-fiber laser-Doppler flowmetry. Blood flow in superficial cortex and inner medulla was measured with a probe directed towards the kidney surface and exposed papilla, respectively. Outer medullary blood flow was measured with a probe introduced through the renal core. After ischemia the blood flow decreased to 60% of the pre-ischemic value (P < 0.01) in superficial cortex and to 16% (P < 0.01) in outer medulla, while inner medullary blood flow increased paradoxically to 125% (P < 0.01). There was extensive trapping of red blood cells (RBC) in the outer medulla, but not in the inner medulla or cortex. The fractional RBC volume as measured by radiolabeled RBCs was 21% in the inner stripe of the outer medulla, but 2% in this area in a normal kidney. To investigate the influence of RBC trapping on intrarenal distribution of blood flow after ischemia, the hematocrit was reduced from 46% to 31% by isovolemic hemodilution. When performed before ischemia, this maneuver almost completely abolished RBC trapping. In this group blood flow in both outer and inner medulla was almost unchanged after ischemia, while superficial cortical blood flow decreased to 66% (P < 0.01) of the pre-ischemic value. It is concluded that RBC trapping in the outer medulla causes a large decrease in blood flow in this area and, at the same time, shunting of blood to the inner medulla. In the absence of RBC trapping, blood flow of both outer and inner medulla is well preserved after ischemia

Campaign of aerodynamic measurements in a wind tunnel

2017/201

Photoinhibition of photosynthesis in natural assemblages of marine phytoplankton

A new empirical equation is introduced that describes the photosynthesis by phytoplankton as a single, continuous function of available light from the initial linear response through the photoinhibited range at the highest light levels liable to be encountered under any natural conditions. The properties of the curve are derived, and a procedure is given for fitting it to the results of light-saturation experiments for phytoplankton...

Crude Oil Remote Sensing, Characterization and Cleaning with CW and Pulsed Lasers

For detection, identification and characterization of crude oil we combine several optical methods of remote sensing of crude oil films and emulsions (coherent fringe projection illumination (CFP), holographic in-line interferometry (HILI), and laser induced fluorescence). These methods allow the three-dimensional characterization of oil spills, important for practical applications. Combined methods of CFP and HILI are described in the frame of coherent superposition of partial interference patterns. It is shown, that in addition to detection/identification laser illumination in the green-blue region can also degrade oil slicks. Different types of surfaces contaminated by oil spills are tested: oil on the water, oil on the flat solid surfaces and oil on the curved surfaces of pipes. For the detection and monitoring of the laser-induced oil degradation in pipes, coherent fiber bundles were used. Both continuous-wave (CW) and pulsed lasers are tested using pump-probe schemes. This finding suggests that properly structured laser clean-up can be an alternative environmentally-friendly method of decontamination, as compared to the currently used chemical methods that are dangerous to environment

Predicting Effects of Ocean Warming, Acidification, and Water Quality on Chesapeake Region Eelgrass

Although environmental requirements of seagrasses have been studied for years, reliable metrics for predicting their response to current or future conditions remain elusive. Eelgrass (Zostera marina L.) populations of the Chesapeake region lie near the southern limit of their range in the Western North Atlantic, exposing them to increasing thermal stress as the climate warms. However, CO2 stimulated photosynthesis may offset some of the negative effects of temperature stress. The combined effects of temperature, CO2, and light availability controlled by water quality and epiphytes were explored using GrassLight, a bio-optical model that provided a predictive environment for evaluating the interaction of multiple stressors on eelgrass distribution and density across the submarine landscape. Model predictions were validated against in situ measures of spectral diffuse attenuation, eelgrass density, and distribution. The potential for photosynthesis stimulated by ocean acidification to mitigate the effects of high temperature on eelgrass populations growing near the southern limit of their distribution was explored. The model accurately reproduced the submarine light environment from measured water quality parameters, and predicted their impacts on eelgrass distribution. It also reproduced the negative effects of warm summer temperatures on eelgrass distributions, and demonstrated that CO2 increases projected for the next century should stimulate photosynthesis sufficiently to offset the negative effects of thermal stress on eelgrass growing in the Chesapeake region, even in the presence of epiphytes. Thus, improved water quality should facilitate the survival of eelgrass populations in Chesapeake region, even in the face of a warming climate

Lifestyle changes in descendants of parents with diabetes type 2

O objetivo geral do estudo foi explorar à disposição à mudança dos padrões alimentares e atividade física nos descendentes de progenitores com diabetes mellitus tipo 2 (DMT2). Aplicou-se un desenho descritivo correlacionar. A base teórica constituiu-se pelo Componente Genético (h²) e o Modelo Transteorético de Prochaska. Participaram 30 progenitores com DMT2 e 60 descendentes. Resultados e Conclusões: O 68% dos descendentes presentaram obesidade, 60% com risco de doença cardiovascular, 42% com resistência à insulina (RI) e 15% intolerância à glucose; nenhum dos fatores de risco associaram-se com as etapas de mudança. O componente genético para RI foi mínimo (h² = 1.37%). Uma maior proporcão dos menores de 40 anos (Xi² = 6.04, p = .020) e das mulheres (Xi² = 4.41, p=.040) contemplam diminuir o consumo de gorduras. Os resultados sugerem um maior peso dos fatores do meio ambiente sobre o estilo de vida nocivo dos participantes.El objetivo general del estudio fue explorar la disposición al cambio de patrones alimentarios y actividad física en descendientes de progenitores con diabetes mellitus tipo 2 (DMT2), aplicando un diseño descriptivo correlacional. La base teórica la constituyó el componente genético heredabilidad (h²) y el Modelo Transteorético de Prochaska; participaron 30 progenitores con DMT2 y 60 descendientes. Resultados y Conclusión: El 68% de los descendientes fueron obesos, 60% con riesgo de enfermedad cardiovascular, 42% con resistencia a la insulina (RI) y 15% intolerantes a la glucosa; ninguno de los factores de riesgo se asoció con las etapas de cambio. El componente genético para RI fue mínimo (h² = 1.37%). Una mayor proporción de menores de 40 años (p = .020) y de mujeres "contemplan" disminuir el consumo de grasas (p = .040). Estos resultados sugieren un mayor peso de factores del medio ambiente sobre el estilo de vida nocivo de los participantes.This study aimed to explore the disposition of diabetic parents' descendents in changing eating and physical activity patterns. It was based on the heritability concept and Prochaska's Transtheoretical Model. This is a descriptive-correlational study; participants included 30 parents, randomly selected, and 60 children. Results and conclusion: 68% of the children was classified as obese, 42% with insulin resistance, and 15% with carbohydrate intolerance. None of the risk factors was associated with the stages of change. The heritability factor was 1.37%; more people younger than 40 and women report decreasing in the consumption of fat food (Xi² = 6.04, p = .020; and 4.41, p = .040, respectively). These results suggest a high influence of environmental factors on the participants' unhealthy life styles