80 research outputs found
Effects of statins on endothelial function and lipid profile in HIV infected persons receiving protease inhibitor-containing anti-retroviral combination therapy: a randomised double blind crossover trial
Effect of Deficit Irrigation and Root-Zone Drying Irrigation Technique under Different Nitrogen Rates on Water Use Efficiency for Potato (Solanum Tuberosum L.) in Semi-arid Conditions (I)
An investigation was carried out at the Technical Center of Potato and Artichoke CTPTA in the region of Saida, located in the lower valley of Medjerda river during the season of 2017. The objective was to evaluate the effects of deficit irrigation (DI) and the root-zone drying irrigation technique (PRD) under different nitrogen rates on total dry matter production (TDM), water consumption (WC) and water use efficiency of potato (Solanum Tuberosum L. VS. Spunta). Three water treatments (T1 = FI = 100% ETC, T2 = DI = 75% ETC and T3 = PRD50) and three nitrogen rates (F1 = N150: 150 kg N ha-1, F2 = N75: 75kg N ha-1, F3 = N0: 0kg N ha-1) were applied since the tuber initiation (55 days after planting) to maturity (100 days after planting). The results showed that the water regime affected negatively the total dry matter accumulation. A decline of 7 and 18.6% was registered in the two treatments T2 and T3 compared to the control T1. The WC decreased during water restriction respectively by 16; 33 and 29% for the T2 and T3 (PRD50 left) and T3 (PRD50 right) compared to T1. For the three nitrogen treatments (F1, F2 and F3) the water restriction has increased the WUE. The best values was recorded in the treatment T2 and then in the treatment T3 from where this increase compared to T1 was equal to (22.6% and 12.9%), (24.1% and 12, 4%) and (21.9% and 15.3%) respectively
Impact of Deficit Irrigation (DI) and Root-Zone Drying Irrigation Technique (PRD) under Different Nitrogen Rates on Radiation Use Efficiency for Potato (Solanum Tuberosum L.) in Semi-arid Conditions (II)
The study was carried out at the Technical Center of Potato and Artichoke CTPTA located in the lower valley of Medjerda river of Tunisia during the season of 2017. The purpose was to estimate the impact of deficit irrigation (DI) and the root-zone drying irrigation technique (PRD) under different nitrogen rates on photo synthetically active radiation absorbed and radiation use efficiency for Potato (Solanum Tuberosum L. VS. Spunta). Three water treatments (T1= 100% ETC, T2 = DI = 75% ETC and T3 = PRD50) and three nitrogen rates (F1 = N150: 150 kg N ha-1, F2 = N75: 75kg N ha-1, F3 = N0: 0kg N ha-1) were applied since the tuber initiation (55 days after planting) to maturity (100 days after planting). The deficit irrigation T2 has no effect on PARabs. Besides, the PRD50 has led to a reduction in PARabs. This decrease compare to T1 was equal to (8.9; 9.9 and 7.9%) respectively for the three treatments (F1; F2 and F3). The nitrogen deficit affects negatively the PARabs. An improvement of 13.2%, 11.2% and 12.2% of the F1 compared to the F3, respectively for the three water treatments (T1, T2 and T3). The T2 has no effect on RUE TDM. Conversely, the PRD50 has led to a reduction in RUE TDM. This decline referee against T1 was equal to (12.7; 17.4 and 21.5%) respectively for the three treatments (F1; F2 and F3). For RUEGY statistical analysis showed significant (P < 0.05) difference between the three irrigation treatments (T0, T1 and T2) for the three nitrogen treatments (F1; F2 and F3). The T2 and the PRD50 has led to a reduction in RUE GY. This decrease judge against T1 respectively for the two treatments (F2 and F3) was equal to (14.9 and 21.5%) and (19.6 and 31.2%)
Characterization of in-situ Doped Polycrystalline Silicon Using Schottky Diodes and Admittance Spectroscopy
In this work, Schottky Au-Polycrystalline silicon diodes are successfully realised. The barrier height is around Đ€B = 0.74 eV as determined from Capacitance â Bias (C-V) characteristics. The depth profile of the apparent doping is deduced from these measurements. Its behaviour leads to the experimental profile. Moreover, the diode admittance measurements versus the frequency and the temperature at different biases show the possibility to use this device to characterise the electrical quality of the polycrystalline silicon
Two different hematocrit detection methods: Different methods, different results?
BACKGROUND: Less is known about the influence of hematocrit detection methodology on transfusion triggers. Therefore, the aim of the present study was to compare two different hematocrit-assessing methods. In a total of 50 critically ill patients hematocrit was analyzed using (1) blood gas analyzer (ABLflex 800) and (2) the central laboratory method (ADVIA(R) 2120) and compared. FINDINGS: Bland-Altman analysis for repeated measurements showed a good correlation with a bias of +1.39% and 2 SD of +/- 3.12%. The 24%-hematocrit-group showed a correlation of r2 = 0.87. With a kappa of 0.56, 22.7% of the cases would have been transfused differently. In the-28%-hematocrit group with a similar correlation (r2 = 0.8) and a kappa of 0.58, 21% of the cases would have been transfused differently. CONCLUSIONS: Despite a good agreement between the two methods used to determine hematocrit in clinical routine, the calculated difference of 1.4% might substantially influence transfusion triggers depending on the employed method
Noninvasive cardiac output and blood pressure monitoring cannot replace an invasive monitoring system in critically ill patients
Background: Monitoring of cardiac output and blood pressure are standard procedures in critical care medicine. Traditionally, invasive techniques like pulmonary artery catheter (PAC) and arterial catheters are widely used. Invasiveness bears many risks of deleterious complications. Therefore, a noninvasive reliable cardiac output (CO) and blood pressure monitoring system could improve the safety of cardiac monitoring. The aim of the present study was to compare a noninvasive versus a standard invasive cardiovascular monitoring system.
Methods: Nexfin HD is a continuous noninvasive blood pressure and cardiac output monitor system and is based on the development of the pulsatile unloading of the finger arterial walls using an inflatable finger cuff. During continuous BP measurement CO is calculated. We included 10 patients with standard invasive cardiac monitoring system (pulmonary artery catheter and arterial catheter) comparing invasively obtained data to the data collected noninvasively using the Nexfin HD.
Results: Correlation between mean arterial pressure measured with the standard arterial monitoring system and the Nexfin HD was r2 = 0.67 with a bias of -2 mmHg and two standard deviations of ± 16 mmHg. Correlation between CO derived from PAC and the Nexfin HD was r2 = 0.83 with a bias of 0.23 l/min and two standard deviations of ± 2.1 l/min; the percentage error was 29%.
Conclusion: Although the noninvasive CO measurement appears promising, the noninvasive blood pressure assessment is clearly less reliable than the invasively measured blood pressure. Therefore, according to the present data application of the Nexfin HD monitoring system in the ICU cannot be recommended generally. Whether such a tool might be reliable in certain critically ill patients remains to be determined
Anthropogenic, direct pressures on coastal wetlands
Coastal wetlands, such as saltmarshes and mangroves that fringe transitional waters,
deliver important ecosystem services that support human development. Coastal
wetlands are complex social-ecological systems that occur at all latitudes, from polar
regions to the tropics. This overview covers wetlands in five continents. The wetlands
are of varying size, catchment size, human population and stages of economic
development. Economic sectors and activities in and around the coastal wetlands and
their catchments exert multiple, direct pressures.Chinese Academy of Sciences (CAS-YIC) scholarship and SKLECECNU project 111 scholarship<, Natural
Resources Canada contribution no. 20200070; Fundação para a CiĂȘncia e a Tecnologia (FCT) Scientific
Employment Stimulus Programme (CEECIND/01635/2017). and (CEECIND/00095/2017),
(UID/MAR/00350/2019CIMA) and (UID/MAR/04292/2019)info:eu-repo/semantics/publishedVersio
Effects of Anesthetic Agents on Brain Blood Oxygenation Level Revealed with Ultra-High Field MRI
During general anesthesia it is crucial to control systemic hemodynamics and oxygenation levels. However, anesthetic agents can affect cerebral hemodynamics and metabolism in a drug-dependent manner, while systemic hemodynamics is stable. Brain-wide monitoring of this effect remains highly challenging. Because T2*-weighted imaging at ultra-high magnetic field strengths benefits from a dramatic increase in contrast to noise ratio, we hypothesized that it could monitor anesthesia effects on brain blood oxygenation. We scanned rat brains at 7T and 17.2T under general anesthesia using different anesthetics (isoflurane, ketamine-xylazine, medetomidine). We showed that the brain/vessels contrast in T2*-weighted images at 17.2T varied directly according to the applied pharmacological anesthetic agent, a phenomenon that was visible, but to a much smaller extent at 7T. This variation is in agreement with the mechanism of action of these agents. These data demonstrate that preclinical ultra-high field MRI can monitor the effects of a given drug on brain blood oxygenation level in the absence of systemic blood oxygenation changes and of any neural stimulation
Constitutive Overexpression of Muscarinic Receptors Leads to Vagal Hyperreactivity
BACKGROUND: Alterations in muscarinic receptor expression and acetylcholinesterase (AchE) activity have been observed in tissues from Sudden Infant Death Syndrome (SIDS). Vagal overactivity has been proposed as a possible cause of SIDS as well as of vasovagal syncopes. The aim of the present study was to seek whether muscarinic receptor overexpression may be the underlying mechanism of vagal hyperreactivity. Rabbits with marked vagal pauses following injection of phenylephrine were selected and crossed to obtain a vagal hyperreactive strain. The density of cardiac muscarinic receptors and acetylcholinesterase (AchE) gene expression were assessed. Blood markers of the observed cardiac abnormalities were also sought. METHODOLOGY/PRINCIPAL FINDINGS: Cardiac muscarinic M(2) and M(3) receptors were overexpressed in hyperreactive rabbits compared to control animals (2.3-fold and 2.5-fold, respectively) and the severity of the phenylephrine-induced bradycardia was correlated with their densities. A similar overexpression of M(2) receptors was observed in peripheral mononuclear white blood cells, suggesting that cardiac M(2) receptor expression can be inferred with high confidence from measurements in blood cells. Sequencing of the coding fragment of the M(2) receptor gene revealed a single nucleotide mutation in 83% of hyperreactive animals, possibly contributing for the transcript overexpression. Significant increases in AchE expression and activity were also assessed (AchE mRNA amplification ratio of 3.6 versus normal rabbits). This phenomenon might represent a compensatory consequence of muscarinic receptors overexpression. Alterations in M(2) receptor and AchE expression occurred between the 5th and the 7th week of age, a critical period also characterized by a higher mortality rate of hyperreactive rabbits (52% in H rabbits versus 13% in normal rabbits) and preceeded the appearance of functional disorders. CONCLUSIONS/SIGNIFICANCE: The results suggest that cardiac muscarinic receptor overexpression plays a critical role in the development of vagal hyperreactivity, whereas AchE hyperactivity appears as a compensatory consequence of it. Since similar vagal disorders were observed recently by us in SIDS, muscarinic receptor overexpression could become a marker of risk of vasovagal syncopes and SIDS
- âŠ