49 research outputs found
Calidad de fruto y aceite de olivos maduros en condiciones de cultivo de secado parcial de la zona radical
This study was conducted to evaluate the quantitative and qualitative effects of partial rootzone drying (PRD) irrigation on olive trees and their fruit and oil quality. Olive trees of the Moroccan Picholine variety were grown under arid conditions in Marrakech, and exposed to four irrigation treatments: Control (irrigated with 100 % of the crop evapotranspiration, on the two sides of the root system), PRD1 (irrigated with 50 % of the control, on one side of the root system, switching every two weeks), PRD2 (irrigated with 50 % of the control, on one side of the root system, switching every four weeks) and PRD3 (irrigated with the same amount of water as the control applied on one side of the root system, switching every two weeks). The individual fruit weight, dimensions and oil contents were generally greater under PRD than the control. Whereas, the fruit water content was lower under PRD1 and PRD2 than the control and PRD3. Oil acidity was not affected by irrigation, while the total polyphenol content, which affects the oxidative stability and sensory characteristics of the oil, increased in response to the PRD irrigation, especially under PRD1 (246.0 ppm) and PRD2 (278.5 ppm) treatments, against 148.4 ppm and 101.8 ppm for PRD3 and the control respectively. This increase could explain the oil bitterness observed under PRD1 and PRD2. The fatty acid composition was not affected by PRD1 and PRD2. The oil quality based on UV absorption coefficients (K232 and K270) decreased significantly under PRD2. Chlorophyll content and maturity index were antagonistic, and olive ripeness was found to be precocious under PRD irrigation treatments compared to the control.Este estudio fue realizado para evaluar los efectos cuantitativos y cualitativos de la irrigación de olivos por secado parcial de la zona radical (PRD) sobre la calidad de su fruto y de su aceite. Los olivos de la variedad marroquí Picholine fueron cultivados en condiciones áridas en Marrakech, y expuestos a cuatro tratamientos de irrigación: Control (irrigado con el 100 % de la evapotranspiración de la cosecha, en los dos lados del sistema radical), PRD1 (irrigado con el 50 % del control, en sólo un lado del sistema radical, cambiando cada dos semanas), PRD2 (irrigado con el 50 % del control, en un lado del sistema radical, cambiando cada cuatro semanas) y PRD3 (irrigado con la misma cantidad del agua que el control aplicado en un lado del sistema radical, cambiando cada dos semanas). El peso individual del fruto, sus dimensiones y el contenido en aceite fueron generalmente mayores bajo PRD que en el control. Mientras que, el contenido de agua de la aceituna fue inferior en PRD1 y PRD2 que en el control y en PRD3. La acidez del aceite no se afectó por el régimen de irrigación, mientras que el contenido total de polifenoles, que afecta a la estabilidad oxidativa y a las características sensoriales del aceite, aumentó en respuesta a la irrigación mediante PRD, sobre todo con los tratamientos PRD1 (246.0 ppm) y PRD2 (278.5 ppm), frente a los 148.4 ppm y 101.8 ppm de PRD3 y el control, respectivamente. Este aumento podría explicar el amargor del aceite obtenida con PRD1 y PRD2. La composición de ácidos grasos no fue afectada por PRD1 Y PRD2. La calidad del aceite basada en los coeficientes de absorción UV (K232 y K270) disminuyó considerablemente con PRD2. El contenido de clorofila resultó antagonista del índice de madurez, y éste último se desarrolló más precozmente en los tratamientos de irrigación PRD que en el control
Selection of tomato plant families using characters related to water deficit resistance
Cosmic ray oriented performance studies for the JEM-EUSO first level trigger
JEM-EUSO is a space mission designed to investigate Ultra-High Energy Cosmic Rays and Neutrinos (E > 5 ⋅ 1019 eV) from the International Space Station (ISS). Looking down from above its wide angle telescope is able to observe their air showers and collect such data from a very wide area. Highly specific trigger algorithms are needed to drastically reduce the data load in the presence of both atmospheric and human activity related background light, yet retain the rare cosmic ray events recorded in the telescope. We report the performance in offline testing of the first level trigger algorithm on data from JEM-EUSO prototypes and laboratory measurements observing different light sources: data taken during a high altitude balloon flight over Canada, laser pulses observed from the ground traversing the real atmosphere, and model landscapes reproducing realistic aspect ratios and light conditions as would be seen from the ISS itself. The first level trigger logic successfully kept the trigger rate within the permissible bounds when challenged with artificially produced as well as naturally encountered night sky background fluctuations and while retaining events with general air-shower characteristics
Using oxide-trap charge-pumping method in radiation-reliability analysis of short lightly doped drain transistor
In this paper, a thorough investigation of the application possibilities of the oxide-trap charge-pumping (OTCP) extraction method to evaluate the radiation-induced traps in short lightly doped drain (LDD) transistors is conducted. We have successfully demonstrated that the OTCP is able to determine all kind of traps induced by radiation in short LDD transistors. First, we have presented a methodical approach to take out the LDD effect from CP curves, leaving only the effective channel-length CP. Second, we have extracted the radiation-induced interface, oxide, and border traps for LDD-NMOSFET and LDD-PMOSFET with varied gate length and fixed gate width. Finally, we have performed a comparison between OTCP and subthreshold slop (STS), midgap (MG), dual-transistor CP (DTCP), and DT border trap (DTBT). OTCP method shows perfect agreement with all methods regarding oxide-trap (??N ot) extraction versus gate length. However, it does not correlate with STS and MG for interface trap (??N it) , because the latter methods overestimate ??N it by sensing border trap (??Nbt) as an interface trap. We have observed the same behaviors in the narrow LDD transistors. The OTCP method estimates ??N ot for N- and P-MOSFET separately, while DTCP and DTBT give average density for whole N- and P-MOS devices. Unlike DTCP and DTBT, OTCP can be applied on a single transistor using a single-measurement techniqu
Why is oxide-trap charge-pumping method appropriate for radiation-induced trap depiction in MOSFET?
Radiation-induced traps, which are generally identified using specific extraction methods, play an important role in the reliability of MOS devices. In this paper, the oxide-trap-based-on-charge-pumping (OTCP) method is used to estimate radiation-induced oxide, interface, and border traps in complementary N- and P-MOS transistors. We emphasize on the critical comparison between the OTCP and classical methods like subthreshold slope (STS), midgap (MG), capacitance-voltage (CV), dual-transistor CP (DTCP), and DT border trap (DTBT), giving a clear insight on the benefits and limitations of OTCP. According to experimental data, the OTCP method is often more accurate than the classical methods. On one side, OTCP offers more accurate densities of radiation-induced interface traps (DeltaN it) and border traps (DeltaN bt), while STS and MG overestimate DeltaN it because both interface and border traps are sensed like interface traps. On the other side, OTCP estimates DeltaN it, DeltaN bt, and oxide trap (DeltaN ot) for N- and P-MOSFETs separately, while DTCP and DTBT give average densities for whole N- and P-MOS devices. Finally, DeltaN ot obtained by OTCP is in excellent agreement with that given by CV. However, they show a slight discrepancy in the DeltaN it extractio
Radiation effect evaluation in effective short and narrow channels of LDD transistor with LOCOS isolation using OTCP method
In this paper, we have presented a new methodology to take out the local oxidation of silicon (LOCOS) and lightly doped drain (LDD) subdiffusion effects from charge-pumping (CP) curves, leaving only the CP current of the effective channel, in narrow- and short-channel MOSFET transistors. First, we have clarified the contribution of LDD-subdiffusion and LOCOS regions to the CP characteristics by studying the spatial distributions of CP threshold and flatband voltages. We have shown that the maximum CP current is the contribution of pumped current in the effective-channel, LOCOS, and LDD-subdiffusion regions. Second, we have successfully used the oxide-trap CP (OTCP) to extract the radiation-induced oxide trap (??N ot) and interface trap (??N it) in effective short- and narrow-channel transistors. Finally, we have performed a comparison between the OTCP and the capacitance-versus-voltage metho
Fast and simple method for estimation and separation of radiation-induced traps in MOSFETs devices
In this work, we propose a simple and fast method to estimate the radiation-induced traps in P and N-MOS transistors independently. This method is based on standard current-voltage and Charge Pumping (I(V)-CP) to separate the radiation-induced border-traps (N bt) and true interface-traps (N it), where the radiation-induced oxide-traps (N ot) are extracted classically by measuring the threshold voltage (V th) or Mid-Gap (V mg) voltage shift. The charge pumping (CP) curves are measured using the rise and fall saw-tooth signal for N-and P-MOS transistors respectively, to minimize the border-trap estimation error caused by the difference in the energy band gap scanned by standard I(V) and CP techniques. Emphasis is made on critical comparison between the radiation induced N bt extracted using I(V)-CP and classical method such as OTCP and DTBT. According to experimental data, the I(V)-CP method is more accurate than OTCP and DTBT methods, since it is more sensitive than OTCP method for the extraction of border traps and it can gives all kinds of traps for P and N-MOS transistors separatel
Modeling and simulation of charge-pumping characteristics for LDD-MOSFET devices with LOCOS isolation
We propose a model for the so-called constant-amplitude charge-pumping (CP) characteristics, giving the Elliot Gaussian-like CP current curve (ICP-VL) of lightly doped drain (LDD) MOSFET with local oxidation of silicon (LOCOS). This method is based on modulation of the contributing active-channel area (AG) to the ICP-VL curve, depending on the position of the high and low levels of the gate signal voltage. In addition, it allows to separate and clarify the contribution of all MOSFET regions (such as the effective channel, LDD, LOCOS, and LDD subdiffusion under the LOCOS) to the amount of ICP-VL curves. We have simulated this model and compared with experimental CP data. The model shows a very good correlation with experimental ICP-VL curves, particularly for transistors with short channel gate lengths (LG ≤ 1 μm). However, as the channel gate length increases, the model matches only for rising and falling ICP-VL curve edges, corresponding to the contribution of LDD and LOCOS regions, respectively. Moreover, we have demonstrated that the deviation, which was observed between the CP model and experimental data at the maximum plateau of ICP-VL characteristics, depends on the gate pulse fall time and vanishes for large fall time. This difference has been found to behave like a geometric component, since it depends on gate length and fall time and disappears for both short gate lengths and long fall time
Use of Human Fibrin Glue and Amniotic Membrane Transplant in Corneal Perforation
peer reviewedPURPOSE: To repair corneal perforation using human fibrin glue (HFG) and amniotic membrane transplant (AMT). METHODS: Three patients in whom central corneal perforations, approximately 2 mm in diameter, occurred after ocular or systemic disease were successfully cured using HFG and AMT. The technique consists first of using a high-viscosity sodium hyaluronate viscoelastic material to restore anterior chamber depth followed by a debridement of the ulcer. The perforation site is filled with the HFG to corneal surface level. The so-formed plug is then secured with an AMT to avoid its extrusion. An extended-wear bandage contact lens and topical antibiotics were used in these patients for 3 weeks. RESULTS: Total reepithelialization was observed after an average of 15 postoperative days. The AMT dissolved within 8 weeks to uncover a whitish scar formed within the perforation sites. No complications were observed in any patients. After a follow-up period of 195-325 days, all corneas remained stable; there was no infection or ulcer recurrence, but some corneal scar thinning was observed in all three cases. CONCLUSION: The described surgical approach using HFG and AMT allowed a successful repair of corneal perforations with a diameter of 2 mm associated with significant loss of stroma. This method may be a good alternative to delay penetrating keratoplasty for treating corneal perforations, especially in acute cases in which graft rejection risk is high. ea