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This paper introduces an induction machine-based flywheel energy storage system (FESS) for direct integration with a variable-speed wind generator (VSWG). The aim is to connect the FESS at the DC bus level of a permanent magnet synchronous generator-based VSWG in order to stabilize the DC bus voltage as well as the power flowing into the grid. A rotor flux-oriented control strategy is proposed for the FESS converter based on the actual speed of the flywheel rotor. Since mechanical speed sensors are prone to failure and increase the maintenance cost of the system, a sensorless technique is proposed to estimate the rotor speed through a specially synthesized high-gain observer (HGO). The proposed observer achieves accurate tracking of the flywheel speed and flux and reduces the adverse effects of variations in the rated rotor resistance. Simulation results obtained using the MATLAB-Simulink environment are presented to illustrate the theoretical synthesis and analysis of the proposed FOC and sensorless HGO control strategies. [ABSTRACT FROM AUTHOR]

Summary: The optimal control problem that hinges on the Euler‐Lagrange equation can be applied to electric‐machine drives and the necessary and sufficient optimality conditions around the system control and the control variables can be designed in a congruent way. In this paper, a variational problem is proposed to minimize energy consumption by an Induction Motor (IM) under a Rotor Field–Oriented Vector Drive (RFOVD) during torque and speed transients. The optimal stimulus is to take into account real applications, like perturbed load torques, and an abrupt speed input. The approach consists of an off‐line algorithm that minimizes a cost functional or integral of the weighted sum of IM energy/power under the dynamic stress of the rotor flux and of rotation speed. The variational problem leads to a nonlinear differential equation known as the Euler‐Lagrange equation. A new method is suggested to run out an analytical solution and results in a time‐varying rotor flux considered as the optimal state variable of the dynamic IM model that saves energy of the IM drive under RFOVD. This solution provides loss‐minimization in steady‐state operations at an infinite horizon and performs adaptive suboptimal minimum‐energy consumption for torque transients. Simulation and experimental results are fully performed on 1.5‐kW laboratory IM, and prove the validity of the proposed method for both steady‐state and transient‐IM drive operations. [ABSTRACT FROM AUTHOR]

The general purpose of this paper is to develop new aspects of bifurcation structures in a 3D parametric space. Identification of generic bifurcation structures in former studies was based on the arrangement of bifurcation curves in the parameter plane. So by analogy to such studies, we define the bifurcation surface in 3D parameter space as the main feature of the said generic structures. The implementation of this idea is made on the permanent magnet synchronous machine (PMSM) whose speed is regulated with a field-oriented control (FOC). Sufficient conditions are given for the existence of three main bifurcations: limit point (LP), Hopf (H) and Bogdanov–Takens (BT). Starting from bifurcation curves traced in a parameter plane and changing a third parameter, a qualitative bifurcation surface is constructed in a 3D parametric space. This led to underline the increasing complexity of the bifurcation structures when dealing with more than two parameters. This study put into evidence not only the complex behavior of PMSM, but stands as a starting point for a new formalism on the bifurcation structures in a 3D parametric space. [ABSTRACT FROM AUTHOR]

Agriculture plays an important role in the economy of the Maghreb region. Most of the water needed for irrigation comes from pumping of the aquifers. A controlled pumping of the groundwater resources does not exist yet, thus, estimating the total water consumption for agricultural use only with in situ data is nearly impossible. In order to overcome this lack of information, Copernicus data are used for determining the groundwater withdrawal through agriculture in the Maghreb region. This paper presents an approach for estimating and monitoring crop water requirements in Tunisia based on multitemporal Sentinel-2 data. Using this multitemporal information, a thorough analysis of the different culture types over time is possible, from which a set of additional multitemporal features is deduced for crop type classification. In this paper, the contribution of those features is analyzed, showing a classification accuracy enhanced by 10% with the multitemporal features. Furthermore, relying on existing methods and FAO standards for the estimation of crop water needs, the methodology aims to estimate the specific crop water consumption. The results of the water estimates are validated against delimited areas where estimates of the water consumption are available from the authorities. Finally, as the study is conducted within the framework of an international technical cooperation, the methodology aims to be reproducible and sustainable for local authorities. The particularity of the results presented here is that they are achieved through automatic processing and using exclusively Open Source solutions, deployable on simple workstations. [ABSTRACT FROM AUTHOR]

Objective: We assessed publication bias in the field of systemic lupus erythematosus (SLE) by conducting a search of randomized, controlled trials (RCTs) on SLE therapies that had been published over the past 45 years. Our aim was to assess a potential publication bias by determining whether RCTs reporting positive results, RCTs with placebo arms, biologics RCTs, and industry-funded RCTs are more likely to be published in journals with higher impact factors (IFs). Methods: We conducted a systematic review of all RCTs registered in PubMed between 1 January 1975 and 1 November 2016. Each RCT was classified as having a positive result (PR) or a negative result (NR). The IF of each journal was determined for the year of publication. Results: Our search yielded 233 relevant RCTs. There was no significant difference in IFs between studies with NRs and those with PRs or between studies that were financially supported by commercial companies compared to studies that were not. However, there was a significant correlation between sample size and the journal's IF. Conclusions: IF scores of RCTs in the field of SLE are influenced by sample size and not biased by either a tendency to report PRs or by being funded by pharmaceutical companies or any other commercial sources. [ABSTRACT FROM AUTHOR]

The installed energy production capacity of wind turbines is growing intensely on a global scale, making the reliability of wind turbine subsystems of greater significance. However, many faults like Inter-Turn Short-Circuit (ITSC) may affect the turbine generator and quickly lead to a decline in supplied power quality. In this framework, this paper proposes a Sliding Mode Observer (SMO)-based Fault Tolerant Control (FTC) scheme for Induction Generator (IG)-based variable-speed grid-connected wind turbines. First, the dynamic models of the wind turbine subsystems were developed. The control schemes were elaborated based on the Maximum Power Point Tracking (MPPT) method and Indirect Rotor Flux Oriented Control (IRFOC) method. The grid control was also established by regulating the active and reactive powers. The performance of the wind turbine system and the stability of injected power to the grid were hence analyzed under both healthy and faulty conditions. The robust developed SMO-based Fault Detection and Isolation (FDI) scheme was proved to be fast and efficient for ITSC detection and localization. Afterwards, SMO were involved in scheming the FTC technique. Accordingly, simulation results assert the efficacy of the proposed ITSC FTC method for variable-speed wind turbines with faulty IG in protecting the subsystems from damage and ensuring continuous connection of the wind turbine to the grid during ITSC faults, hence maintaining power quality. [ABSTRACT FROM AUTHOR]

This paper describes fault-tolerant control strategies for a Permanent Magnet Synchronous Generator (PMSG)-based Marine Current Turbine (MCT) dealing with the generator-side converter under faulty conditions. MCT system mainly used PI controllers. However, this type of controllers is very sensitive to faulty conditions such as an open circuit faults in the generator-side converter. As consequence, the MCT system represents a high decrease in its power generation and dynamic performances. In this faulty context, firstly, a fault tolerant structure consists in requiring only minimum hardware modifications to the converter is proposed. In the second part, a backstepping and a second-order sliding mode nonlinear control are therefore investigated for fault-tolerant control purposes. A comparison between the different control strategies is proposed to prove the most robust one. [ABSTRACT FROM AUTHOR]

In this article, the dynamic responses of wind turbine systems are analytically and numerically investigated. For this purpose, analytic differential equations of motion of wind turbine components subjected to vibration (the blades, the nacelle, and the tower) are solved. This allows determining their dynamic characteristics, mode shapes, and natural frequencies. Two models of two three-dimensional (3D) micro-turbine that are created by the finite element method are set up using the new version of the academic finite element analysis software ANSYS. The first wind turbine is a standard micro three-bladed turbine and the second one is a micro six-bladed Rutland 504. Their natural frequencies and mode shapes are identified based on the modal analysis principle to check the validity of designed models. Dynamic behaviors at several operating conditions of wind turbines are established. Then, spectrum graphs of the structures along x-, y- and z-axis are analyzed. [ABSTRACT FROM AUTHOR]

The fresh peel essential oils of citrus aurantium from Eastern Morocco (Oujda) were analyzed by the gas chromatography and gas-chromatography-mass-spectrometry. The analyzed essential oil mainly consists of monoterpene hydrocarbons (54.38%) with limonene (52.67%) as the major constituent. The effect of addition of citrus aurantium essential oil on the corrosion of steel in a 1 M HCl solution was studied by the weight-loss measurements, potentiodynamic polarization, and the electrochemical impedance spectroscopy (EIS) measurements. The inhibition efficiency was found to increase with the inhibitor content to attain 95% (for 5 g/liter). The data obtained from the EIS studies were analyzed to determine the model inhibition process by using the appropriate equivalent circuit models. The inhibition efficiencies obtained by different methods are in good agreement. It was discovered that the adsorption of natural products on the steel surface obeys the Langmuir's adsorption isotherm. [ABSTRACT FROM AUTHOR]

The concentration of ozone at the Earth's surface is measured at many locations across the globe for the purposes of air quality monitoring and atmospheric chemistry research.We have brought together all publicly available surface ozone observations from online databases from the modern era to build a consistent data set for the evaluation of chemical transport and chemistry-climate (Earth System) models for projects such as the Chemistry-Climate Model Initiative and Aer-Chem-MIP. From a total data set of approximately 6600 sites and 500 million hourly observations from 1971-2015, approximately 2200 sites and 200 million hourly observations pass screening as high-quality sites in regionally representative locations that are appropriate for use in global model evaluation. There is generally good data volume since the start of air quality monitoring networks in 1990 through 2013. Ozone observations are biased heavily toward North America and Europe with sparse coverage over the rest of the globe. This data set is made available for the purposes of model evaluation as a set of gridded metrics intended to describe the distribution of ozone concentrations on monthly and annual timescales. Metrics include the moments of the distribution, percentiles, maximum daily 8-hour average (MDA8), sum of means over 35 ppb (daily maximum 8-h; SOMO35), accumulated ozone exposure above a threshold of 40 ppbv (AOT40), and metrics related to air quality regulatory thresholds. Gridded data sets are stored as netCDF-4 files and are available to download from the British Atmospheric Data Centre (doi:10.5285/08fbe63d-fa6d-4a7ab952- 5932e3ab0452).We provide recommendations to the ozone measurement community regarding improving metadata reporting to simplify ongoing and future efforts in working with ozone data from disparate networks in a consistent manner. [ABSTRACT FROM AUTHOR]

The concentration of ozone at the Earth's surface is measured at many locations across the globe for the purposes of air quality monitoring and atmospheric chemistry research. We have brought together all publicly available surface ozone observations from online databases from the modern era to build a consistent dataset for the evaluation of chemical transport and chemistry-climate (Earth System) models for projects such as the Chemistry-Climate Model Initiative and Aer-Chem-MIP. From a total dataset of approximately 6600 sites and 500 million hourly observations from 1971-2015, approximately 2200 sites and 200 million hourly observations pass screening as high-quality sites in regional background locations that are appropriate for use in global model evaluation. There is generally good data volume since the start of air quality monitoring networks in 1990 through 2013. Ozone observations are biased heavily toward North America and Europe with sparse coverage over the rest of the globe. This dataset is made available for the purposes of model evaluation as a set of gridded metrics intended to describe the distribution of ozone concentrations on monthly and annual timescales. Metrics include the moments of the distribution, percentiles, maximum daily eight-hour average (MDA8), SOMO35, AOT40, and metrics related to air quality regulatory thresholds. Gridded datasets are stored as netCDF-4 files and are available to download from the British Atmospheric Data Centre (doi:10.5285/08fbe63d-fa6d-4a7a-b952-5932e3ab0452). We provide recommendations to the ozone measurement community regarding improving metadata reporting to simplify ongoing and future efforts in working with ozone data from disparate networks in a consistent manner. [ABSTRACT FROM AUTHOR]

More than 2 years of columnar atmospheric aerosol measurements (2006-2009) at the Tamanrasset site (22.79° N, 5.53° E, 1377ma.s.l.), in the heart of the Sahara, are analysed. Aerosol Robotic Network (AERONET) level 2.0 data were used. The KCICLO (K is the name of a constant and ciclo means cycle in Spanish) method was applied to a part of the level 1.5 data series to improve the quality of the results. The annual variability of aerosol optical depth (AOD) and Ångström exponent (AE) has been found to be strongly linked to the convective boundary layer (CBL) thermodynamic features. The dry-cool season (autumn and winter) is characterized by a shallow CBL and very low mean turbidity (AOD ~0.09 at 440 nm, AE ~0.62). The wet-hot season (spring and summer) is dominated by high turbidity of coarse dust particles (AE ~0.28, AOD ~0.39 at 440 nm) and a deep CBL. The aerosol-type characterization shows desert mineral dust as the prevailing aerosol. Both pure Saharan dust and very clear sky conditions are observed depending on the season. However, several case studies indicate an anthropogenic fine mode contribution from the industrial areas in Libya and Algeria. The concentration weighted trajectory (CWT) source apportionment method was used to identify potential sources of air masses arriving at Tamanrasset at several heights for each season. Microphysical and optical properties and precipitable water vapour were also investigated. [ABSTRACT FROM AUTHOR]

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The Saharan heat low ( SHL) is defined as a stationary thermal depression below 700 hPa located over the Sahara during the boreal summer season. This feature has a significant impact on the seasonal and intra-seasonal variability of rainfall over the Sahel. For various reasons, few observations are assimilated in operational numerical weather prediction models, especially surface sensitive observations. In this study we make use of the advanced microwave sounding unit ( AMSU-A) brightness temperatures measured at 52.8 GHz (noted A4 hereafter) and at 53.6 GHz (noted A5 hereafter) to detect the heat low and to characterize its intensity at the seasonal and intra-seasonal scales. In terms of seasonal variability, AMSU-based estimates of SHL are found in good agreement with those based on the European Center Medium-range Weather Forecast ERA-I reanalyses for the period ranging from 2000 to 2011. However, differences exist between the two datasets at intraseasonal timescale. They may be related to mismatches between the numerical weather prediction model levels and the level of maximum of sensitivity of the AMSU observations. Particular meteorological situations can also explain some differences between the two types of products, as there is a lack of assimilated observations in this region. Finally, we show that the A4 brightness temperature is a suitable proxy to provide a good estimate of the location and the intensity of the SHL from daily to seasonal timescales. [ABSTRACT FROM AUTHOR]

The use of renewable energy is growing significantly in the world. In front of the growing demand for electric energy, essentially for the needs of remote, desolate, and mountainous regions, photovoltaic systems, especially water pumping systems, are beginning to emerge in large applications. In this sense, the proposed study deals with the problem of the water level regulation in the photovoltaic pumping system. To achieve this aim, a fuzzy logic controller has been developed in order to determine the reference speed needed for vectorial command of induction motor, taking into account the water level in the tank and the variation of solar irradiation. On the one hand, the energy management and control of the photovoltaic subsystem is based on voltage and current control with maximum power point tracking allowing the optimal transfer of power to the pump through two converters, a boost (DC-DC converter) and an inverter (DC-AC converter) are controlled by space vector pulse width modulation. On the other hand, the proposed study provides a comparison between a fuzzy logic controller and an algorithm controller. The latter technique is less successful than the first, but more easily implemented. The string of photovoltaic pumping is simulated under Matlab-Simulink. The results were promising, and yet they remain to be validated in practice. [ABSTRACT FROM AUTHOR]

To convert wind power into electricity, many types of generator concepts have been used. The main wind turbine generators can be grouped into two classes : fixed and variable speed. In this paper, a characteristic study for integration of fixed speed and variable speed grid-connected wind generators, has been presented. The first is based on a squirrel cage induction generator (IG) connected directly to the grid. The second is a permanent magnet synchronous generator (PMSG)-based variable-speed wind turbine connected to the grid. The performances of each studied wind generator are evaluated by simulation works and variable speed operation is highlighted as preferred mode of operation. [ABSTRACT FROM AUTHOR]

This paper investigates the capabilities of a proposed control strategy designed to enhance phase current profile in switched reluctance machine (SRM) drives. The new developed control concept can significantly accomplish the performance of the SRM in terms of efficiency, torque ripple and power quality when compared to standard PWM current control. This control consists of feeding each phase with a constant volt per hertz (V/f) law for low speed range. The suggested V/f method is simple and is easy for practical implementation. Principle of this mode of control and analytical expressions for current calculation are provided and discussed. Obtained simulation results demonstrate the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

We report in this article the design and calculated molecular properties of 18 new mono-cyclic β-lactams 4-21, on the basis of one hypothetical antibacterial pharmacophore structure designed to interact with both of Gram-positive bacteria and Gram-negative bacteria. The in vitro biological evaluation of these compounds allowed us to point out new potential non-nucleoside hits, with MIC values in the range of 2-8 μg/mL active against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. A correlation structure/antibacterial activities relationship of these monocyclic β-lactams is described. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

Cynodon dactylon (Poaceae family) decoction was used in the treatment of kidney stones. However, no scientific study was undertaken so far to demonstrate the beneficial effect of the plant. Thus, the aim of the current study is to evaluate the effect of Cynodon aqueous extract as a preventive and curative agent in experimentally induced nephrolithiasis in a rat model. Ethylene glycol (EG) was used in the experiment to induce calcium oxalate (CaOx) deposition into kidneys. In preventive protocol, Cynodon decoction was administered in the same day with EG to evaluate the ability of the extract to prevent crystal deposition. However, in curative protocol, rats were first rendered nephrolithiasic and then the extract was administered to assess the ability of the plant to eliminate the pre-existing crystal deposition. In both protocols, urinary biochemical and other variables were measured during the course of the study. Crystalluria and renal histology were examined as well. The results showed that, in both protocols, all measured variables were similar for both the rat groups. Nevertheless, urinary biochemical analysis was apparently unaffected by the extract except oxalate in preventive protocol, and calcium, sodium, and potassium in curative protocol which were significantly highly excreted in treated rats compared to untreated animals. Crystalluria was characterized mostly by the presence of large quantities of CaOx monohydrate and CaOx dihydrate particles in untreated rats. However, crystalluria was mainly dominated by the presence of CaOx dihydrate particles with reduced size. The most apparent beneficial effect of Cynodon extract was seen in kidney tissues where reduced levels of CaOx deposition have been noticed especially in medullary and papillary sections from treated rats. We concluded that C. dactylon extract has beneficial effect in preventing and eliminating CaOx deposition into kidneys. Such findings provide a scientific explanation for its use in the treatment of kidneys stones. [ABSTRACT FROM AUTHOR]

OBJECTIVE To evaluate the prophylactic potential of a herbal decoction from Herniaria hirsuta, a medicinal plant widely used in Morocco to treat kidney stones, by assessing the effect of oral administration in experimentally induced calcium oxalate (CaOx) nephrolithiasis in rats. MATERIAL AND METHODS Two groups of six rats each were rendered nephrolithic by treating with ethylene glycol 0.75% and ammonium chloride 1% for 3 days, and then ethylene glycol only for 3 weeks. Maintained on ethylene glycol, one group of rats was also given 1 mL/day of the plant decoction, while the others received 1 mL of water instead for 2 weeks. Urine samples (24 h) were collected individually at 1, 3, 7, and 14 days for physicochemical analysis. On completing the treatment the kidneys were collected and analysed by light microscopy. RESULTS The water intake and diuresis decreased in the treated rats; there was no significant difference in urinary pH between the groups. Urinary chemistry was apparently unaffected by the plant extract, except for the magnesium content, which was higher in treated rats. Crystalluria was characterized by the excretion of large CaOx monohydrate and dihydrate crystals in untreated, but smaller crystals in treated rats. The histology showed large deposits of CaOx crystals in all parts of the kidney in untreated rats but with almost no deposits in those of treated rats. CONCLUSION H. hirsuta has an impressive prophylactic effect on CaOx stones in nephrolithic rats; the effect did not seem to be mediated by biochemical or diuretic changes. [ABSTRACT FROM AUTHOR]

The effect of breastfeeding on the development of allergic rhinitis and other atopic conditions has been assessed in many studies but remains controversial. To elucidate this issue, a systematic review was conducted of prospective studies that evaluated the association between exclusive breastfeeding during the first 3 mo after birth and allergic rhinitis. The 1966-2000 MEDLINE databases were searched and the reference lists of relevant articles were reviewed according to predetermined inclusion criteria. The methodological aspects of each study, duration and exclusivity of breastfeeding, outcome measures, control for potential confounding variables and other factors were assessed, and estimates of the association between breastfeeding and allergic rhinitis were abstracted independently by the investigators using a standardized approach. Six prospective studies met the inclusion criteria. The summary odds ratio for the protective effect of breastfeeding was 0.74 (95% confidence interval 0.54-1.01). The effect estimate in studies of children with a family history of atopy was 0.87 (95% confidence interval 0.48-1.58). Conclusion: Exclusive breastfeeding during the first 3 mo after birth protects against allergic rhinitis in children, both with and without a family history of atopy. The protective association, although of borderline statistical significance, was substantial. Larger prospective studies with strict methodology and longer periods of follow-up are needed. [ABSTRACT FROM AUTHOR]

Unlabelled: The aim of the study was to investigate the clinical presentation and prognosis of recurrent facial nerve palsy (RFNP) in children. The files of 182 patients referred to the Schneider Children's Medical Centre of Israel for neurological evaluation of isolated peripheral facial nerve palsy between October 1992 and December 1998 were reviewed. RFNP was found in 11 patients (9 females, 2 males), with an incidence of 6%. In two males, the aetiology was traced to Melkersson-Rosenthal syndrome and these patients were separated from the rest of the group. Three children had two episodes of facial nerve paresis which completely resolved clinically within several weeks. Six other children underwent electrophysiological studies. Two of the latter with residual neurological damage, and one child with abnormal blink reflex only, showed decreased facial nerve conduction velocity and abnormal blink reflex. Three children with complete recovery had disturbed blink reflex only with normal nerve conduction. Brain imaging studies as well as laboratory work-up were non-contributory in all cases.Conclusion: The frequency of recurrent facial nerve palsy in children was similar to that in adults. The most significant factors in the evaluation of recurrent facial nerve palsy are medical history and physical findings at diagnosis and after short follow-up. In our patients, electrophysiological studies did not have either clinical or prognostic significance. The rate of full clinical recovery is about 70%, lower than in Bell palsy. [ABSTRACT FROM AUTHOR]

Unlabelled: The objective of this study was to evaluate the structure and contents of the websites of the major journals in general pediatrics. A comprehensive search of the Internet was carried out to identify all pediatric journals in English that are listed in the Scientific Citation Index. Websites of 11 journals in general pediatrics were found, and their Web pages were systematically compared. Two of the appraised websites provided free on-line access to the full journal text, seven had on-line abstracts, and all provided the table of contents. The contents and abstracts covered varying periods, mostly just a few years back. Most of the journals offered easy search and other navigational options, but only a few allowed electronic submission of manuscripts.Conclusion: We conclude that in the era of immense growth and dissemination of information, aimed either at medical professionals or their patients, general pediatrics journals are lagging behind. The pediatrician today remains dependent on hospital libraries and their limited and sometimes cumbersome capabilities. Only a few of the pediatric journal websites can serve as an efficient on-line source for updating the knowledge. Further developments in the future should allow for improved services. [ABSTRACT FROM AUTHOR]

Newly appearing oral motor apraxia should alert physicians to the possibility of an organic lesion in the operculum, the perisylvanian cortex. A 6½‐year‐old boy who is being followed for complex partial seizures with secondary generalization failed to respond to carbamazepine and then to the addition of sodium valproate. The further addition of lamotrigine stopped the seizures but the patient presented with a new onset of opercular syndrome, manifested by severe oral motor apraxia with difficulties in chewing and swallowing and speech. MRI study of the brain revealed no abnormalities. The opercular syndrome resolved completely when the lamotrigine was replaced with phenobarbital, and did not recur during the follow‐up period of 2 years. The EEG, however, continued to be abnormal. We conclude that opercular syndrome may be a manifestation of abnormal localized electrical activity at the operculum, even in the absence of an organic lesion on imaging studies, and it may be a marker for an epilepsy which is not easily controlled. [ABSTRACT FROM AUTHOR]

Water is a very limited resource in Tunisia, both in quantity and in quality. Problems of quality are related to urban, industrial and agricultural activity. Erosion is causing dams to silt up and is leading to phosphorus accumulation in water. The use of agrochemicals, primarily nitrogen and phosphorus, is causing problems of eutrophication. This paper presents the results of a study of sediment and nitrate pollution. The methodology used is based on the EPIC simulation model and a multi-objective programming model (MOPM). The data generated by EPIC are input for the MOPM together with the economic variables. These tools are applied to a 486 ha farm located in northern Tunisia which includes an irrigated area of 300 ha. The study considers three objectives: maximization of gross margin, minimization of erosion, and minimization of nitrate losses. The non-inferior set estimation method is implemented to generate the trade-off curves between the objectives. Results show that nitrate losses are important for both rainfed and irrigated land. The same conclusion is valid for erosion. It is shown that the farmer can reduce the environmental burden without decreasing gross margin, since he is operating below the efficiency curve. [ABSTRACT FROM AUTHOR]

Unlabelled: Acute isolated infectious sphenoiditis is an uncommon, potentially dangerous condition which is often misdiagnosed because of its nonspecific symptoms and paucity of clinical signs. We present eight children with isolated sphenoiditis who were managed in our medical centre during the last 2 years and review the literature. All the patients were adolescents or pre-adolescents and all experienced moderate to severe refractory oppressive headache. Four had a history of sinusitis or allergic rhinitis. None had fever or any other directing clinical sign. Diagnosis was made by cranial computer tomography. All were treated with antibiotics and recovered completely without infectious or neurological complications.Conclusion: Acute isolated infectious sphenoiditis should be considered in adolescents and pre-adolescents who present with constant moderate to severe oppressive headache. Awareness of this entity will enable early diagnosis and initiation of antibiotic treatment which is essential to avoid complications and surgical intervention. [ABSTRACT FROM AUTHOR]

A 12 year old boy and his two sisters with Hashimoto's thyroiditis and renal impairment were studied. Three generations of this family had autoimmune thyroid disease: Graves' disease was diagnosed in the first generation, and the second and third generations had thyroid enlargement with abnormal thyroid function and immunological abnormalities. The disease in this family could not be explained simply by the types of human leucocyte antigens found. Renal disease in autoimmune thyroid disease is uncommon, treatment difficult, and the prognosis unknown. The proteinuria disappeared in all three children during the three and a half years of follow up, which implies that the renal impairment may be transitory in some patients. [ABSTRACT FROM AUTHOR]

Fifteen infants with seborrheic dermatitis were treated with topical glucocorticosteroids (flumethasone pivalate 0.02%). Early morning plasma cortisol levels were determined prior to treatment, during the 10-day treatment period, and 2 days after its termination. The mean plasma cortisol level prior to treatment was 8.8 ± 3.4 µg%; after 2 days of application there was a significant decrease of the mean to 2.5 ± 1.3 µg% that persisted throughout the treatment period. Two days after termination of treatment, the mean plasma cortisol level rose to 7.1 ± 3.7 µg% but in five infants was still less than 5 µg% and in two less than 2 µg%, the latter two having shown the greatest involvement of the skin. The possibility of pituitary/adrenocortical inhibition similar to that observed with the systemic administration of glucocorticosteroids and the potential associated risks should be considered when treating cases that would require extensive application of flumethasone pivalate in infants. [ABSTRACT FROM AUTHOR]

Six children and adolescents (aged from 2 6/12 to 16 years) with isolated hGH deficiency were subjected to a standard oral glucose tolerance test (OGTT) followed by the administration of IV glucagon at 180 mins. Three of them underwent a second test after several months of hGH therapy. Nine patients underwent a separate IV glucagon test and two of these patients had both tests. As controls served 14 endocrinologically normal children and adolescents, who underwent both tests. It was found that the patients with isolated hGH deficiency had lower basal plasma insulin and blood glucose levels and that their insulin response to IV glucagon even after oral glucose preloading was significantly lower than in the control group. This response was partially restored by several months of hGH treatment in the three patients tested. These findings are interpreted as further evidence for an insulinotrophic effect of hGH. [ABSTRACT FROM AUTHOR]