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This paper explores the impact of balconies on the energy demand required for cooling in the arid climate zone of the city of Adrar, in Algeria. For the purpose to assess several situations of the balconies, we have chosen a parametric method based on a campaign of thermal simulations. The open and eliminated balcony type were selected and characterized by four parameters: the balcony to room ratio, the orientation, the window type, and the balcony position. A set of 100 simulations was selected randomly based on the Monte-Carlo probability technique. The final sample was corrected based on Cook's distance which gave 85 simulations as a final sample size. A generalized regression model was performed to identify the impact of each parameter. The accuracy of the model is above 97% and the sensitivity analysis shows that the most important factor is the balcony to room ratio which could reduce the energy demand up to 26% followed by the window type (24%), the orientation (8%) and the balcony position (5%). This conclusion stresses the idea of considering the balcony as a passive solution to reduce the cooling energy demand. [ABSTRACT FROM AUTHOR]

In this paper, a low-cost monitoring system for an off-grid photovoltaic (PV) system, installed at an isolated location (Sahara region, south of Algeria), is designed. The PV system is used to supply a small-scale greenhouse farm. A simple and accurate fault diagnosis algorithm was developed and integrated into a low-cost microcontroller for real time validation. The monitoring system, including the fault diagnosis procedure, was evaluated under specific climate conditions. The Internet of Things (IoT) technique is used to remotely monitor the data, such as PV currents, PV voltages, solar irradiance, and cell temperature. A friendly web page was also developed to visualize the data and check the state of the PV system remotely. The users could be notified about the state of the PV system via phone SMS. Results showed that the system performs better under this climate conditions and that it can supply the considered greenhouse farm. It was also shown that the integrated algorithm is able to detect and identify some examined defects with a good accuracy. The total cost of the designed IoT-based monitoring system is around 73 euros and its average energy consumed per day is around 13.5 Wh. [ABSTRACT FROM AUTHOR]

Evaluation and modeling of soil water infiltration are essential to all aspects of water resources management and the design of hydraulic structures. Nonetheless, research focused on experimental studies of infiltration rates in arid and semi-arid regions under unknown boundary conditions remains minimal. This paper investigates the characteristics of the spatial variability of infiltration over a semi-arid rural basin of Algeria. The experiments were conducted using a portable double-ring infiltrometer filled at an equal volume of approximately 100 L of water for each of the 25 catchment locations. Soil moisture contents at the proximity of each test location were evaluated in the laboratory as per the standard NF P94–050 protocol. The experimental results are used to produce the catchment infiltration curves using three statistically fitted infiltration models, namely Horton, Kostiakov, and Philip models. The reliability of the models was assessed using four performance criteria. The statistical regressions of the fitted models suggest that the Horton model is the most suitable to assess the infiltration rate over the catchment with mean coefficients of Nash = 0.963, CC = 0.985, RMSE = 1.839 (cm/h), and Bias = 0.241. The superiority of the Horton model suggests that the initial and final infiltration rates, primarily affected by soil type, initial soil moistures, and land cover, are important predictors of the modeling process over the Madjez Ressoul catchment. The results also infer that the applicability of other models to the different types of undeveloped soils in the study area requires advanced field investigations. This finding will support the understanding of the hydrologic processes over semi-arid basins, especially in advising crop irrigation schemes and methods and managing the recurring flood and drought over the country. [ABSTRACT FROM AUTHOR]

Camel breeding remains marginal in Algeria but represents an invaluable animal resource for desert regions. The camel is one of the few domestic species that provides milk, meat, leather, wool, manure and work. The Algerian camel herd has experienced a significant increase in recent years, reaching a population of about 416,500 in 2019. This livestock is located in 17 Wilayates, including 8 Saharan and 9 Stepppiques. The main breeds raised in Algeria are: the Chaambi, Ouled Sidi Cheikh, Ait Khebbach, Steppe Camel, Saharaoui, Targui, Ajjer, Reguibi and Ftouh. The camel sector in Algeria is facing several constraints of a sanitary, genetic, logistical and organizational nature. The management of land and common spaces, following the sedentarization of some breeders, is another difficulty that the sheep sector must face. Several favorable factors for camel breeding in Algeria, such as the pedoclimatic diversity of the country, culture/religion, economic and genetic diversity, can help to improve Algerian red meat production. The objective of this paper is to present the current situation of camel farming in Algeria. [ABSTRACT FROM AUTHOR]

Arid regions around the world are characterized by hard summer and winter seasons, which leads to thermal discomfort. The southwest of Algeria is classified as an arid region, where the temperature in the summer season passes sometimes 50 °C in the shade and reaches negative values in the winter season. In addition, the yearly relative humidity is below 50%. The hard thermal and hygrometric situation requires actions to fulfill the thermal comfort requirements. Air-conditioning systems are a solution, but at the same time, they are responsible for a big amount of energy consumption in the building sector. In the present paper, an experimental investigation is conducted on the performance of a coupled system: earth-to-air heat exchanger and a solar chimney. The main purpose is to reduce costs and maximize the direct effect between the two techniques. The obtained results showed that the new system was able to create two main thermal regimes in the same day. The first one is a 'heating' by increasing the outlet air temperature passing through the buried pipe and solar chimney to reach a maximum gain of 14 °C in day 3. The second thermal regime is the 'cooling' that is made by reducing the air temperature at the EAHE outlet by 11.6 °C on day 5. It is also observed that the system increases the outlet air relative humidity by 46% due to the condensation phenomena and reduces it sometimes by 45%. The recent model made of the two techniques was able to produce between 3 and 20 Watts of heating/cooling capacity at the outlet of the system. [ABSTRACT FROM AUTHOR]

Earth to air heat exchanger EAHE is a renewable technique based on a geothermal source. Arid regions are characterised by hard winter and summer weather conditions, which lead to a large thermal discomfort for the big part of the year. In this paper, we study by experiments the performance of stand-alone earth-to-air heat exchanger without external devices (fans, etc.), but only with the local climatic conditions of the region of Bechar (located in the Southwest of Algeria). The EAHE contains a PVC pipe with 66 meters of length and 110 mm of diameter, and it is buried at a depth of 1.5 m in an agriculture zone, where the annual undisturbed subsoil at 1.5 m is 28°C. The stand-alone EAHE has the capacity to raise the air temperature by 10°C in the heating regime and reduce it by 11.9°C in the cooling regime. Furthermore, the relative humidity is raised by19% in the humidification regime and reduced by 27% in the dehumidification regime. The daily working regime was: 62.5% of heating (from 00h to 08h and from 18h to 23h) and 37.5% of cooling (from 09h to 17h) for the thermal regime, 62.5% of dehumidification (from 00h to 09h and from 18h to 23h) and 37.5% of humidification (from 10h to 17h) for the hygrometric regime. The stand-alone EAHE technique presents a great potential for the pre-heating, pre-cooling, and natural ventilation of dwellings and buildings in arid regions. [ABSTRACT FROM AUTHOR]

The paper aims to assess the impact of climate change on sustainable development in the case of the High Plateaux region of Algeria. A baseline "climate change" scenario and an "adaptation" scenario were assessed as part of our work. The methodological approach implemented is broken down into three interconnected evaluation phases, pre-modelling phase, modelling phase and post-modelling phase. The work has shown that these complex ex-ante evaluation approaches are adaptable and applicable in the context of Algeria. Our findings indicate that climate change would have a significant impact on economic aggregates on a regional scale. It also highlighted that the calculation of a single index of the impact of environmental policies on the sustainability of arid regions confirms the hypothesis of gaining sustainability by working towards a strategy of adaptation to climate change. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to focus on the concept of agritourism and how its development and promotion can contribute to the achievement of a number of sustainable development objectives, including those related to reducing inequalities, fighting poverty, sustainable consumption and production and ensuring food security. Design/methodology/approach: Professionals and experts in the fields of agriculture, aquaculture and tourism were interviewed to better understand the challenges of agritourism and how it could contribute to the achievement of sustainable development objectives in mountainous and arid regions. Findings: The results highlight the environmental, economic and social benefits that can be derived from the practice of agritourism and how this can be a distinguishing feature for a country in which conventional tourism is struggling to develop. participation in farm life for various activities is a key element of any agritourism activity. The results also confirmed the various benefits of the practice, both for farmers and tourists and that it contributed directly to the achievement of certain objectives such as poverty alleviation, reduction of inequalities, food security and preservation of water resources. Research limitations/implications: This research has certain limitations, the first being the fact that it is a qualitative study and the results cannot be extrapolated; second, it only took into account the point of view of a certain category of people, namely, experts and tourism professionals. Originality/value: New elements were also identified, in particular, concerning certain perceived risks related to the practice of agritourism such as bio-piracy or damage to national heritage, as well as the appropriation and use of ancestral practices for commercial purposes by other countries. [ABSTRACT FROM AUTHOR]

Due to the economic and environmental risks posed by fossil fuels, the use of renewable energies has become necessary. Geothermal energy, which extracts heat from the ground to heat or cool buildings, has not taken its place in Algeria as our economic and management reality. According to the importance of this study and to attract researchers to use this new technique in arid areas. Optimization methods are the most favorable, economical and less expensive to give a valid estimate of the results among these methods is fuzzy logic. This paper present numerical optimization of air temperature for diameter, flow and length by using fuzzy logic. For this propose, the experimental findings used to predict the reason of air temperature in buried pipe in arid zone. The accuracy it's about 99.3%. The extended model and the experimental findings were determined to be in good agreement using the fuzzy logic technique. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate the quality of groundwater used for irrigating agricultural areas in the region of Ouargla by using several quality indices and to map the spatial distribution of these indices. This spatial mapping will help create a model for the classification of these resources according to their suitability for irrigation. For this purpose, physicochemical analyses were carried out on samples from 38 wells distributed over the entire territory of the studied region. These include 27 wells that capture Mio-Pliocene groundwater (Terminal Complex) and 11 wells in the Albian groundwater (Intercalary Continental). The thematic maps were developed using a geographic information system (GIS). In this study, we used the following eight indices: potential salinity (PS); residual sodium carbonate (RSC); electrical conductivity (EC); magnesium percent (%Mg2+); sodium percent (%Na+); permeability index (PI); Kelley's ratio (KR); sodium adsorption ratio (SAR). The global qualitative study of the water used for irrigation shows that these resources fall into three categories (good, permissible, and poor for irrigation). Water quality analysis shows that, based on the magnesium percent (%Mg2+), 18% of the wells can be considered to be of good quality, 74% of the wells are of medium quality (permissible for irrigation), and 8% are of poor quality (unsuitable for irrigation). According to the Wilcox diagram, the waters used in the Ouargla region are of very poor quality. Very excessive mineralization, expressed by the electrical conductivity, was observed for the Mio-Pliocene and Albian waters, where it varies with values in the range of 2340 µS/m to 6520 µS/m and 2330 µS/m to 3840 µS/m, respectively. This conductivity presents a high risk of alkalinization. [ABSTRACT FROM AUTHOR]

Faced with the challenges of sustainable groundwater resource management in the arid zone, the identification of reserves and their monitoring have become vital. This paper aims to identify the Turonian aquifer in the Cretaceous Béchar basin, and calculate its transmissivity, permeability and storage coefficient, as well as its evolution over time. This Turonian aquifer is characterized by marine limestones (gentle dip shelters 45° to the North and 5° to 10° to the South). Pumping tests revealed a transmissivity T of 10–4 to 10–2 m²·s–1, a permeability K of 10–6 to 10–4 m·s–1 and a storage coefficient S of approximately 10–3. Two piezometric campaigns, carried out between (1976–2018), show a converging and constant flow direction from the North–East to the South–West and from the North–West to the South–East towards the outlet of the basin. Decreased values were observed in the North and South–West borders due to isopiezometric lines. However, this water table is not in a stationary state, it shows seasonal and interannual fluctuations in relation to the variable rainfall and the exploitation rate. In terms of facies, the projection of the two hydrochemical campaigns, during 1976 and 2018 on the Piper diagram, did not show any significant evolution, they are concentrated in the chlorinated and sulphated calcium and magnesium facies. [ABSTRACT FROM AUTHOR]

Thermal potential for cooling and heating can be achieved by new configuration of earth–air heat exchanger (EAHE). This paper presents a numerical investigation of thermal performance of a spiral-shaped configuration of EAHE intended for the summer cooling in hot and arid regions of Algeria. A commercial finite volume software (ANSYS FLUENT) has been used to carry out the transient three-dimensional simulations and the obtained results have been validated using the experimental and numerical data obtained from the literature. The agreement between our simulation results and those from literature is very satisfactory. A parametric analysis of the new geometry of (EAHE) has been performed to investigate the effect of pitch, depth, pipe length and of the flow velocity on the outlet air temperature and the EAHE's mean efficiency as well as its coefficient of performance (COP). It has been shown that when the pitch space varies between 0.2 and 2 m the difference of outlet air temperature increases by 6 °C. When the air velocity increases from 2 to 5 m/s the mean efficiency decreases from 60 % to 33 % and the COP of the EAHE decreases from 2.84 to 0.46. [ABSTRACT FROM AUTHOR]

In this paper, the numerical results of the study on geothermal-air heat exchanger in dry areas of Algeria (Ghardaia region) were presented. Computational fluid dynamics equations were solved using our specific code compilated with Fortran. The outputs of the numerical calculations were compared and validated with the experimental results and the outputs of a commercial CFD code. In these conditions, our results present good agreements with an error not exceeding 2%. By using our numerical model, we have calculated the optimum length, the internal diameter, the air velocity of the pipe in winter and summer periods and have determined the optimum depth at different depths. The comparison of two types of pipes making material (PVC and PEHD) has taken into account the characteristics of the Ghardaia-Algeria region (specific heat capacity, density, thermal conductivity and temperature) of the soil. The obtained results proved that the chosen model gives a satisfactory agreement in all the studied variables. [ABSTRACT FROM AUTHOR]

Long-term monthly streamflow forecasting has great importance in the water resource system planning. However, its modelling in extreme cases is difficult, especially in semiarid regions. The main purpose of this paper is to evaluate the accuracy of artificial neural networks (ANNs) and hybrid wavelet-artificial neural networks (WA-ANNs) for multi-step monthly streamflow forecasting in two different hydro-climatic regions in Northern Algeria. Different issues have been addressed, both those related to the model's structure and those related to wavelet transform. The discrete wavelet transform has been used for the preprocessing of the input variables of the hybrid models, and the multi-step streamflow forecast was carried out by means of a recursive approach. The study demonstrated that WA-ANN models outperform the single ANN models for the two hydro-climatic regions. According to the performance criteria used, the results highlighted the ability of WA-ANN models with lagged streamflows, precipitations and evapotranspirations to forecast up to 19 months for the humid region with good accuracy [Nash–Sutcliffe criterion (Ns) equal 0.63], whereas, for the semiarid region, the introduction of evapotranspirations does not improve the model's accuracy for long lead time (Ns less than 0.6 for all combinations used). The maximum lead time achieved, for the semiarid region, was about 13 months, with only lagged streamflows as inputs. [ABSTRACT FROM AUTHOR]

Olea europaea L. 1753, is one of the oldest and most distinctive trees in the Mediterranean region. Its nutritional, social, cultural, and economic value is very important for populations in arid regions, where it is widely distributed. A sign of a sustainable environment in many agricultural regions is the existence of a wide variety and abundance of arthropod groups. The main objective of the study is to evaluate the diversity of arthropods subservientin in olive agro-systems in the arid region by using several sampling techniques, namely classic sight hunting, visual inspection, Barber pots, and yellow traps. The inventory is carried out over a period of 5 months, from February to June 2023, in three stations in M’Sila (northeastern Algeria). Three classes of arthropods were found: Insecta, Arachnida, and Malacostraca. Captures were numerically dominated by Insecta, representing 96.88% of total captures. Arachnida and Malacostraca classes represented about 2.74 and 0.38%, respectively. During this research, a total of 1861 arthropod individuals were collected and identified into 83 species, 79 genera, 53 families, and 15 orders. The most abundant orders were: Diptera (42.56%), Hymenoptera (28.11%), and Coleoptera (7.32%). However, we found a significant difference in species composition according to habitat (P < 0.01). The species were determined, and the ecological indices were calculated (Shannon Value, Evenness values and Simpson reciprocal index). The dominant functional feeding groups were phytophages (41.91 %), predators (32.94%), and polyphages (22.14%). The arthropods included several olive pests such as Euphyllura olivina (Costa) (Hemiptera: Liviidae), Bactrocera oleae (Rossi) (Diptera: Tephritidae), Prays oleae (Bernard) (Lepidoptera: Praydidae), Liothrips oleae Costa (Thysanoptera: Phlaeothripidae), and Oxycenus maxwelli (Keifer) (Arachnida: Eriophyidae). [ABSTRACT FROM AUTHOR]

In mammals, the pregnant female carries many physiological and anatomical changes. Biochemical profiles are very important tools for monitoring gestation progress. This study was designed to investigate pregnancy-related changes of blood metabolites in Ouled Djellal ewes under semi-arid conditions. Blood samples were collected from ten non pregnant multiparous ewes 4 weeks before conception and 4, 12 and 18 weeks of pregnancy age. The pattern of changes of some biochemical parameters were studied. Cholesterol level showed no significant changes during pregnancy, while triglyceride, AST and Ca decreased up to the 12th week of pregnancy, whereas the total protein, albumin, and creatinine increased toward the 12th week of pregnancy. Urea reached maximum levels at the end of the pregnancy, contrary to ALT that was significantly decreased. Glucose concentration showed a continual decrease varying from 2.08 ± 0.78 g.l−1 at the first month of pregnancy to 0.35 ± 0.36 g.l−1 at the 18th week of pregnancy. On the other hand, pregnancy establishment increased significantly the glucose, triglyceride, albumin, and urea, but it decreased significantly the cholesterol and creatinine levels. No differences were observed between pregnant and non-pregnant ewe for the rest of the parameters. These results demonstrated a clear evidence of pregnancy-related distribution of blood biochemical indices of Ouled Djellal ewe under semi-arid conditions. Some substrates and enzymes were mainly higher during the first half of pregnancy (triglyceride, AST and Ca), and some others increased from the mild pregnancy period (total protein, albumin and creatinine), while urea and ALT changes were observed at late pregnancy. The energetic demand increased with advancing pregnancy. [ABSTRACT FROM AUTHOR]

The Setifian high-plains region, Northeast of Algeria, grapples with challenges in water resource management. As the water demand intensifies across a diverse range of sectors, assessing groundwater quality becomes indispensable. This article responds to the critical need for a thorough assessment of groundwater quality in the Wadi Boussellam sub-watershed. Employing a GIS-based method, we evaluate groundwater geochemistry by estimating the Water Quality Index (WQI), offering a comprehensive overview of water consumption. The analysis of groundwater samples reveals distinct facies, including calcic bicarbonate, calcic chloride, calcic sulfate, and magnesium sulfate, contributing to an enhanced understanding of the hydrochemical composition in the Setif region. Hydrochemical indices, specifically the WQI, Sodium Adsorption Ratio (SAR), and Na% are applied to assess groundwater suitability for various applications. The results indicate that most crops are generally suitable for irrigation, though they advise exercising caution with regard to human consumption. This study underscores the significance of regular monitoring to avert groundwater contamination and ensure sustainable use in the Setif region, providing insights that emphasize the ongoing necessity for efforts in water resource management and the preservation of this vital resource's quality. [ABSTRACT FROM AUTHOR]

This research focuses on the evaluation of a heritage office building in the town of Kenadsa in the Southwest of Algeria (a famous oasis in the arid regions of the country). Emphasizing user's perception as a metric key for performance assessment, this study aims to investigate the users' perception and behaviors of a heritage office building on an oasis settlement. The research was conducted in 2023, and employing a multidimensional approach, both quantitative and qualitative methodologies, along with agent-based modeling, were integrated. One qualitative methodology is based on a series of field surveys and the other quantitative methodology relies on in situ measurements of the physical dimensions of the environment. The quantitative aspect involves an agent-based modeling framework, simulating user interactions by incorporating physical dimensions, spatial layout, historical context, and user behavior. The main findings of this study, examining perceptions and behaviors under varying luminous and thermal environments, show that this integrated approach provides insights into user satisfaction, spatial utilization, and the identification of user behaviors and productivity in each office. [ABSTRACT FROM AUTHOR]

Changing of precipitation regime and intensification of extreme storms in semi -arid regions because of climate change requires the use of numerical models to forecast the outlet hydrographs. In this paper, HEC-HMS software was applied using a loss method the curve number CN to estimate the precipitation excess and a parametric unit hydrograph model to compute the transformation of precipitation excess into direct runoff over the watershed. The Muskingum-Cunge routing model was used to simulate the propagation of direct runoff through the main streams of Koudiet Rosfa watershed. The curve number CN and lag time parameters were used to calibrate the model towards several storms. The Nash–Sutcliffe efficiency coefficient (NSE) was adopted to assess the performance of the model to reproduce the observed hydrographs. Volume of the storms, peak discharges, times of peak and times of center of mass between the simulated and observed discharges were used to validate the model. The simulated discharges reproduce the hydrological events. The calibrated model was used to simulate the different hypothetical storms that could occur in the future in order to ensure the safety of Koudiet Rosfa dam towards extreme rainfall-runoff events. [ABSTRACT FROM AUTHOR]

In this paper, a new study has been carried out to analyze the behavior of four different Photovoltaic (PV) module technologies such as the Mono-crystalline silicon, the Multi-crystalline silicon, the amorphous silicon and the Telluride Cadmium as sub-systems from which a 400kWp pilot plant have been constructed at Ghardaia (The northern-central Sahara desert of Algeria). In this work, the results obtained from experimental data acquisition over a period of one year have been analyzed and discussed in terms of plant power production. In addition to that, performance indicators comprising the reference yield, the final yield, the performance ratio, the capacity factor and a newly suggested factor called the power ratio have been used to assess the sub-systems energetic performances. The performances of the studied sub-systems have been compared, then, to those of other systems located in countries regarded as having similar radiometric and climatic conditions. An additional study have been conducted to evaluate the effect of such important climatic and operating parameters as wind speed, ambient temperature, solar irradiance and module temperature on the energetic performances of the studied sub-systems. The experimental results obtained from monitoring of the studied sub-systems indicate that the plant performs best when it is operated under irradiance comprised between 5.56 kWh/m2 and 7.04 kWh/m2 and ambient temperature between 2 °C and 45 °C. Based on energy production and thermal stability results, the present study has allowed the identification of the most efficient and the best suitable of the aforementioned PV technologies for such arid-regions conditions. • Experimental study of the performance of multi-technology PV plant. • Analysis of c-Si, mc-Si, a-Si and Cd–Te PV technologies in the arid region. • Performance analysis with Power Ratio and performance indicators (PR, Yf and CF). • Analysis of the impact of temperature and wind speed on the PV energy production. [ABSTRACT FROM AUTHOR]

This research aims to evaluate the energy conservation potential benefit of earth-shelter building. There are as many types of earth building methods as there are variations in soil, climatic, and cultural conditions. As an alternative to energy consumption in upper-ground building, the underground building was and still one of the oldest building morphology models for thermal issue's solution especially in hot and arid regions. This paper aims to assess the thermal environment of an old underground building in "Bitam" a hot-arid region in Algeria. In order to evaluate the thermal environment assessment of underground buildings, In order to extract the thermal potential, an annual measurement campaigns were conducted for both summer and winter seasons using a digital multifunction monitoring instrumentations (LM/FI20, Testo 865, Testo 830-T2) for the quantification of the thermal advantages and extract most of its bioclimate value especially thermal environments. Thereafter, we use testo software tool "IRSoft" for thermal analysis of the existing underground building and the software "DesignBuilder" will be used for different environment simulations (thermal, CFD and daylighting) of an underground building model. The important findings relate to a high thermal potential using beneficial soil temperature and a large amounts of earth isolation that protect the building envelope from insulation. The underground building model proposed using passive techniques face extreme seasonal climate changes and interacts in a systemic way to enhance indoor thermal comfort. [ABSTRACT FROM AUTHOR]

Durum wheat is one of the major cereal crops in the world as well as in Algeria, where it occupies mainly the semi-arid regions where water deficiency is one of the important abiotic stresses. The improvement of this cereal requires stress-resilient varieties development. The present study aims to evaluate the performance of seven genotypes of durum wheat under greenhouse conditions in order to identify the mechanisms developed by the genotypes to counteract water stress. Yield components, cell turgor, and root characterization were carried out as agronomic, physiological, and morphological evaluation parameters. Two treatments of water stress were applied and compared to non-stressed pot culture. The results showed that the variety Guemgoum rkhem was found to be the most tolerant to water stress and Mohamed Ben Bachir and Fassi were the most sensitive. A significant impact of the different studied parameters on the tested genotypes was recorded indicating variability between them. This study pointed out the considered parameters for appropriate selection of wheat variety adapted to water stress. Despite, the present approach open the way to new perspective to identify the most appropriate wheat variety using other parameters such as selecting target genes responsible for tolerance to water stress and thus facilitate the selection process. [ABSTRACT FROM AUTHOR]

Water resource management scenarios have become more crucial for arid to semi-arid regions. Their application prerequisites rigorous hydrological modelling approaches since data are usually exposed to uncertainties and inaccuracies. In this work, Soil Water Assessment Tool (SWAT), an open source semi-distributed, continuous-time, process-based physical hydrological model is used to model hydrological processes and eventually calculate groundwater recharge estimations in Seybouse basin, Northeast Algeria. The model uses estimated rainfall to calibrate the model with observed discharge from hydrometric stations. Model calibration and validation are performed over four hydrometric stations located in the basin. Uncertainty analysis and sensitivity analysis supported the calibration period. SUFI-2 algorithm is used for uncertainty estimations along with a global sensitivity analysis prior to calibration simulations. Simulated flood hydrographs showed generally good accuracy with few misfits on the peaks. The model obtained satisfactory and consistent calibration and validation results for which the Nash score varied from 0.5 to 0.7 for calibration and from −0.1 to 0.6 for validation and R2 from 0.6 to 0.7 for calibration and 0.03 to 0.8 for validation. Moreover, estimated water budget values show strong similarities with the observed values found in the literature. The present work shows that the rigorously calibrated and validated SWAT model can simulate hydrological processes as well as major high and low flows using estimated rainfall data. [ABSTRACT FROM AUTHOR]

The present paper deals with the assessment of the renewable hydrogen production potential in Algeria. The studied system produces hydrogen by electrolysis of water; electricity is supplied by a photovoltaic generator. Adequate mathematical models were used to calculate the electrolytic hydrogen production. Detailed hourly simulations were used to assess the potential for the entire country and to draw it maps. Throughout this study, the influence of the tilt angle of a photovoltaic generator has been investigated. It has been observed that the tilt angle has an impact on solar energy received by the photovoltaic generator, the produced solar electrical power and the rate of hydrogen production. We have calculated the optimal angles to maximize each element. We were particularly interested in the optimal angle to maximize hydrogen production. We found that the solar hydrogen potential for Algeria varies from 0.10 Nm3/m2/d to 0.14 Nm3/m2/d. This potential is quite significant, especially in the arid region of southeastern Algeria. The lowest potential is located in the northeast region. For stand-alone systems, it is important to assess the minimum available level, as their sizing takes into account the most unfavorable case. This level is between 0.07 Nm3/m2/d and 0.13 Nm3/m2/d. This shows that, even for a stand-alone system, the potential is quite high. Finally, we provide robust correlations that allow calculating the potential and the angle of inclination maximizing it for the whole of Algeria. • The influence of the photovoltaic generator (PVG) on the hydrogen production by alkaline electrolyzer has been described. • The performances of the PVG and electrolyzer for different inclination angles have been investigated. • Maps of hydrogen produced by electrolysis in Algeria has been plotted. • Maps of optimum tilt angle maximizing hydrogen production has been plotted. [ABSTRACT FROM AUTHOR]

We studied the population dynamics of the olive psyllid Euphyllura olivina Costa, 1857 in a semi-arid region (Djelfa, central Algeria) during a year, from December 2017 to November 2018. The visual control approach and the striking method were used to monitor the different stages of this pest. The species had two generations per year: a spring generation from March to June and a fall generation from September to November. The first generation of eggs is laid in March and continues through May. The second generation begins in late August and early September and continues through November. The statistical study of the impact of the researched climatic factors (minimum, maximum, and average temperatures; precipitation and frost) on the various stages differs from one stage to the next. [ABSTRACT FROM AUTHOR]

The assessment of reproduction characteristics of an Algerian local sheep in a semi-arid zone was the objective of this study. Twenty rams of Ouled Djellal breed were used. The parameters analyzed were testosterone rate, testicular diameter, ejaculate volume, sperm concentration, mass motility, and percentage of live and dead spermatozoids (SPZ). The results obtained showed that the mean monthly testosterone rate was high throughout the year (4 ng/mL), increased in spring, peaked in summer (July) (4.9 ng/mL), and decreased in autumn and winter to reach a minimum value (January) of 1.9 ng/mL. Similarly, testicular diameter, ejaculate volume, sperm concentration and count showed high levels in spring and summer and decreased in autumn and winter. The maximum and minimum values were respectively, 7.09 cm, 1.55 mL, 4 billion/mL, 3.5, 79.37%, 21% and 5.46 cm, 0.80 mL, 2.50 billion SPZ/mL, 2.81, 77.36%, and 20.42%. Significant effects of season on serum testosterone levels, testicular conformation, ejaculate volume, and concentration were recorded in this study. Indeed, the rates of these parameters increased significantly (P<0.05) during spring/summer and decreased during autumn/winter except for motility, and the percentage of live and dead sperm. Testicular conformation was positively correlated with testosterone concentration, ejaculate volume, and semen concentration. To conclude, Ouled Djellal breed seemed not to be very sensitive to the photoperiod and little affected by high temperature. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Water & Land Development is the property of Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper reports a phytochemical study of the aerial parts of Astragalus monspessulanus L. growing in Algeria. It deals with the isolation and structure elucidation of 13 known compounds. From the n-butanol extract, seven flavonoids 1-7, two saponins and one lignan were isolated. In addition, two phytosterols and one triterpenoid were isolated from the ethyl acetate extract. Structures of all the isolated products were determined by using 1D and 2D-NMR techniques, measurement of optical rotation, mass spectrometry ESIMS and by comparison with literature data. Furthermore, the antioxidant activity of the n-butanol extract of the aerial parts of Astragalus monspessulanus L. was investigated using the DPPH radical scavenging and ferrous ion chelating assays. The n-butanol extract showed low (EC50 = 2.0876 ± 0.4363 mg/mL) to moderate (IC50 = 63.60 ± 0.01436 μg/mL) antioxidant activities depending on the tested method. [ABSTRACT FROM AUTHOR]

In hot dry regions, the building envelope receives abundant solar radiation, which contributes to heat stress and indoor thermal discomfort. To mitigate overheating inside spaces, cooling is the main basic requirement during most of the year. However, due to the harsh climatic conditions, buildings fail to provide passively the required comfort conditions. Consequently, they are fully dependent on-air conditioning systems, which are huge energy consumers. As roofs are exposed to the sun throughout the daytime, they are estimated to be the main source of heat stress. In return, they can contribute significantly to achieve optimum comfort and energy savings when efficient design strategies are used in an early design stage. To examine the potential for cooling load reduction and thermal comfort enhancement by using cooling roof techniques in residential buildings, a study was performed in the city of Biskra (southern Algeria). Accordingly, an in-field measurement campaign was carried out on test-cells during five days in summer. Three different cooling roof techniques were addressed: (a) cool reflective white paint (CR), (b) white ceramic tiles (CT) and (c) a cool-ventilated roof (C-VR). These roofing alternatives were investigated by monitoring both roof surface temperatures and indoor temperatures. Comparative analysis showed that a cool-ventilated roof is the most efficient solution, reducing the average indoor temperature by 4.95 °C. A dynamic simulation study was also performed based on TRNSYS software to determine the best roofing system alternatives in terms of thermal comfort and energy consumption, considering the hottest month of the year. Simulation tests were run on a base-case model representing the common individual residential buildings in Biskra. Results showed that a double-skin roof combined with cool-reflective paint is the most efficient roofing solution. By comparison to a conventional flat roof, meaningful improvements have been achieved, including reducing thermal discomfort hours by 45.29% and lowering cooling loads from 1121.91 kWh to 741.09 kWh. [ABSTRACT FROM AUTHOR]

The palynological and physicochemical analysis of 62 honey samples produced in different biogeographical areas of Algeria was conducted. Results showed high variety in the botanical origin of samples and their physicochemical profile. Twenty-six samples were polyfloral honey, 30 were unifloral honey from different botanical sources such as Eucalyptus, Citrus, Apiaceae, Punica, Erica, Rosmarinus, Eriobotrya, or Hedysarum, and 6 were characterized as honeydew honey. Pollen analysis allowed the identification of 104 pollen types belonging to 51 botanical families, whereas the physicochemical profile showed important variations between samples. Multivariate techniques were used to compare the characteristics of samples from different biogeographical areas, showing significant differences between humid-area samples, located in the northeast of the country, and samples taken in semiarid, subhumid, and arid zones. Principal-component analysis (PCA) extracted nine components explaining 72% of data variance, being 30%, the sum of Component 1 and Component 2. The plot of both components showed samples grouped upon botanical and geographical origin. The results of this paper highlighted the great variability in honey production of Algeria, evidencing the importance of honey characterization to guarantee authenticity and to valorize local production. [ABSTRACT FROM AUTHOR]

The Atlas pistachio fruits are an important source of food due to their high fat content and medicinal interest in arid lands. For a better use, it is necessary to understand the diversity and distribution of lipids in their fruit. The purpose of the present study is to determine oil content, fatty acid, and phytosterol composition using gas chromatography of three ecotypes in Algeria during two consecutive years. The seed oil contents ranged from 32 to 47.8% depending on both year and ecotype. Unsaturated fatty acids (FA) represent at least 71% of total FA. The fruit contains a considerable level of phytosterols. The highest level of oil content and unsaturated FA were observed in the fruit of Bechar regardless of the part of the fruit. The study indicated that oil quality of the Atlas pistachio seed varies according to genotype and environmental conditions, and the findings could help breeders for diversity and selection program management. [ABSTRACT FROM AUTHOR]

This paper presents a method for economic evaluation and GHGs (greenhouse gases) emissions calculation from a GCRES (grid-connected renewable energy system). An investigation is made on large-scale operations of 67 MWh/day GCRES. A comparison is performed between a GCRES and a standard grid operation focusing on environmental and economic impacts. Emissions and the Renewable energy generation fraction (RF) of total energy consumption are calculated as the main environmental indicators. Costs including NPC (net present cost), COE (cost of energy) and payback period are calculated as the economic indicators. Using the hourly mean global solar irradiance, temperature and wind speed data relative to In Salah and Adrar locations characterized by an arid and hot climate according to the Koppen–Geiger climate classification, a long-term continuous implementation of hybrid renewable energy systems are simulated using HOMER software and are discussed. As results, it is observed that a GCRES reduce 30% and 35% of GHGs emission, and 81% and 76% of COE during the operation phase respectively for In Salah and Adrar. Investments in GCRES should be considered only by planning to produce parts of the equipment locally, which leads to significantly reduce the costs and, consequently, the emissions. [ABSTRACT FROM AUTHOR]

Precise knowledge regarding the quantities of water available in the Wadi Bechar watershed and better management of this resource is necessary to initiate the transformation of rainfall data into hydrometric data (simulated flow); this is the main objective of the hydrological rainfall-runoff modeling. The primary focus of this paper is the rainfall-runoff modeling on an annual and monthly scale in the Wadi Bechar watershed which covers an area of 6858 km2. We employ the rural engineering model (GR) for annual timestep GR1A and for the monthly timestep GR2M. The input parameters are precipitation (P) and evapotranspiration (ETP) calculated by the Turc method; the output parameter is elapsed water slide (Q). The results obtained indicate that the model takes into account the different atmospheric and underground exchanges, as well as the capacities of the production tank and routing tank. With this work, the contribution of precipitation to flows downstream of the watershed can be evaluated and quantified. On an annual scale, the potential evapotranspiration modulator coefficient X is equal to 2.20 > 1. This indicates that the water from the Wadi Bechar watershed seeps into the ground or into the adjacent watersheds of Wadi Zousfana and Wadi Guir. On a monthly scale, we calibrate and cross-validate the model with the selected input data, determining the model parameter sets that best reflect the transformation of rainfall into flow. The calibration was done with several passages in computer. The value of the capacity of the estimated production tank X1 is equal to 4.74 mm, which reflects the production function, and subsequently indicates the rainfall capacity transformed into a water flow available for runoff at the Wadi Bechar watershed scale. The value of the estimated underground exchange coefficient parameter X2 is equal to 0.02; it reflects the transfer function, which indicates the movement of this surface flow toward the watershed outlet. [ABSTRACT FROM AUTHOR]

Optimal estimation of water balance components at the local and regional scales is essential for many applications such as integrated water resources management, hydrogeological modelling and irrigation scheduling. Evapotranspiration is a very important component of the hydrological cycle at the soil surface, particularly in arid and semi-arid lands. Mapping evapotranspiration at high resolution with internalised calibration (METRIC), trapezoid interpolation model (TIM), two-source energy balance (TSEB), and soil-plant-atmosphere and remote sensing evapotranspiration (SPARSE) models were applied using Landsat 8 images for four dates during 2014-2015 and meteorological data. Surface energy maps were then generated. Latent heat flux estimated by four models was then compared and evaluated with those measured by applying the method of Bowen ratio for the various days. In warm periods with high water stress differences and with important surface temperature differences, METRIC proves to be the most robust with the root-mean-square error (RMSE) less than 40 W·m-2. However, during the periods with no significant surface temperature and soil humidity differences, SPARSE model is superior with the RMSE of 35 W·m-2. The results of TIM are close to METRIC, since both models are sensitive to the difference in surface temperature. However, SPARSE remains reliable with the RMSE of 55 W·m-2 unlike TSEB, which has a large deviation from the other models. On the other hand, during the days when the temperature difference is small, SPARSE and TSEB are superior, with a clear advantage of SPARSE serial version, where temperature differences are less important. [ABSTRACT FROM AUTHOR]

Biskra region currently shows signs of stress and a high risk of groundwater contamination by various chemicals and pesticides. For this purpose, a modified integrated susceptibility index (SI) is coupled with remote sensing (RS) and WetSpass model to assess the sensitivity of the groundwater and the risk of pollution in the most exploited aquifer (Quaternary aquifer) in the study area. The results of the modified SI model show that a major part of the aquifer is at risk of contamination if the farmers do not implement good agricultural practices. Four sensitivity levels are considered, reflecting a vulnerability rating that ranges from low to very high. The very high category is observed in the agricultural areas with an estimated pollution index ranging from 84 to 90.57, while a large part of the aquifer shows a high vulnerability to contamination (64 < SI ≤ 84). This category is found in areas characterized by the dominance of bare soil. In urban areas, the vulnerability level decreases to low category (37 < SI ≤ 45). However, the area of forests is classified as moderate to vulnerability (45 < SI ≤ 64). The different statistical and GIS methods confirm the reliability of the obtained SI map. The combination of the SI method with WetSpass model and RS can give a reliable map to help and assist the authorities and decision-makers in groundwater resources planning and the implementation of monitoring programs and networks to control the quality of groundwater in arid environments. [ABSTRACT FROM AUTHOR]

In order to achieve a highly accurate estimation of solar energy resource potential, a novel hybrid ensemble-learning approach, hybridizing Advanced Squirrel-Search Optimization Algorithm (ASSOA) and support vector regression, is utilized to estimate the hourly tilted solar irradiation for selected arid regions in Algeria. Long-term measured meteorological data, including mean-air temperature, relative humidity, wind speed, alongside global horizontal irradiation and extra-terrestrial horizontal irradiance, were obtained for the two cities of Tamanrasset-and-Adrar for two years. Five computational algorithms were considered and analyzed for the suitability of estimation. Further two new algorithms, namely Average Ensemble and Ensemble using support vector regression were developed using the hybridization approach. The accuracy of the developed models was analyzed in terms of five statistical error metrics, as well as the Wilcoxon rank-sum and ANOVA test. Among the previously selected algorithms, K Neighbors Regressor and support vector regression exhibited good performances. However, the newly proposed ensemble algorithms exhibited even better performance. The proposed model showed relative root mean square errors lower than 1.448% and correlation coefficients higher than 0.999. This was further verified by benchmarking the new ensemble against several popular swarm intelligence algorithms. It is concluded that the proposed algorithms are far superior to the commonly adopted ones. [ABSTRACT FROM AUTHOR]

Endophytic strains belonging to the Bacillus cereus group were isolated from the halophytes Atriplex halimus L. (Amaranthaceae) and Tamarix aphylla L. (Tamaricaceae) from costal and continental regions in Algeria. Based on their salt tolerance (up to 5%), the strains were tested for their ability to alleviate salt stress in tomato and wheat. Bacillus sp. strain BH32 showed the highest potential to reduce salinity stress (up to + 50% and + 58% of dry weight improvement, in tomato and wheat, respectively, compared to the control). To determine putative mechanisms involved in salt tolerance and plant growth promotion, the whole genome of Bacillus sp. BH32 was sequenced, annotated, and used for comparative genomics against the genomes of closely related strains. The pangenome of Bacillus sp. BH32 and its closest relative was further analyzed. The phylogenomic analyses confirmed its taxonomic position, a member of the Bacillus cereus group, with intergenomic distances (GBDP analysis) pinpointing to a new taxon (digital DNA-DNA hybridization, dDDH < 70%). Genome mining unveiled several genes involved in stress tolerance, production of anti-oxidants and genes involved in plant growth promotion as well as in the production of secondary metabolites. Key points : • Bacillus sp. BH32 and other bacterial endophytes were isolated from halophytes, to be tested on tomato and wheat and to limit salt stress adverse effects. • The strain with the highest potential was then studied at the genomic level to highlight numerous genes linked to plant growth promotion and stress tolerance. • Pangenome approaches suggest that the strain belongs to a new taxon within the Bacillus cereus group. [ABSTRACT FROM AUTHOR]

Heating capacity of an earth to air heat exchanger EAHE equipped with an exterior fan in the arid region like the Southwest of Algeria is investigated experimentally. In-situ measurement of annual undisturbed subsoil vertical temperature profile is shown that it was 28°C at a depth of 1.5 meters. The EAHE made of 66 meters of PVC tube is demonstrated a heating capacity of 13°C and a cooling capacity of 7°C and a big dependence on local climate conditions. Great potentials and thermal comfort with less energy consumption are represented by earth to air or air-ground heat exchanger in the arid regions like the South of Algeria. [ABSTRACT FROM AUTHOR]

Reservoir dams are critical to agriculture, industry, and the needs of humans and wildlife. This study evaluates the water quality of the Ghrib reservoir in north west of Algeria, using Irrigation Water Quality Index (IWQI), sodium absorption rates (SAR) and multivariate statistical methods (Clustering and principal component analysis). The study concerns the analysis of physical and chemical parameters (pH, EC, O2, TUR, Ca, Mg, HCO3, Na, K, BOD, DCO, Cl−, PO4, SO3. NH4 et NO3) which were measured at 12 selected points along the reservoir over 8 periods (dry and wet periods) using standard methods. Irrigation Water Quality Index values in the dam reservoir were found to be between 41 and 59, according to classifications for different water uses, values below 60 indicate that water is of poor quality for irrigation and treatment is recommended to make reservoir water more suitable for irrigation. The results of water analysis in our study area reveal the presence of acute pollution which is certainly caused by direct releases of either industrial or domestic origin, and we note that this pollution remains variable depending on the collection periods. Also, chloride-calcium and sulfate facies are the most dominant in sampling periods for reservoir water, resulting in poor water quality for irrigation. In addition, water is, therefore, highly mineralized and is likely to be suitable for irrigation of certain species (cucumbers...) that are well tolerant to salt and on well-drained and leached soils. [ABSTRACT FROM AUTHOR]

Asparagus albus L is a medicinal plant that grows spontaneously in the region of Brezina wilaya of El Bayadh. In this work, we made the extraction of flavonoids and alkaloids from the different organs (twigs, bark and roots) plant Asparagus albus to test its antioxidant, and antifungal activities. The antifungal activity is evaluated by the estimated growth is also expressed as a percentage (%) relative to the growth of control. The antioxidant activity of the various extracts of Asparagus albus L using DPPH was evaluated by the spectrophotometric method. Results show that the yield of flavonoids is 9.5% and those of alkaloids is 8.1% The study of the antioxidant power by the method of DPPH radical trapping, reveals the presence of antioxidant properties for the extract studied. The percentage of inhibition most striking was 40.11% of tannins and 55.52% of alkaloids. The evaluation of the antifungal power on Fusarium oxysporum f. sp shows an effect of the extracts on fungi which can be valorised as a fungicide. This result makes Asparagus albus a very promising natural source of antioxidants. [ABSTRACT FROM AUTHOR]

Located in the arid climatic zone of Algeria, the region of Ain Sefra is a victim of climatic change, which faces several geographical, ecological, economic and even social problems. The present study investigated the relationships between various drought indices and the evolution of land use elements in Ain Sefra from 1977 to 2017 using the Modified Soil-Adjusted Vegetation Index. It was revealed that there is a considerable growth of sands estimated at 286.61% of the area, moving toward the north and northeast of the study area during the last decades. The combination of drought indices and remote sensing seems to be most promising, whose results are valuable tools for guidance and decision support to local and regional authorities. [ABSTRACT FROM AUTHOR]

Selecting the appropriate vegetation index for accurate biomass estimation is a prerequisite before and during the ecosystem management project. This study, aims to compare Vegetation Indices (VIs) that are combining both Visible and Near Infrared OLI bands (VNIR-VIs), Visible and Short Wave Infrared OLI bands and also NIR and Short Wave Infrared OLI bands (SWIR-VIs) in order to accurately model the Aboveground Biomass (AGB) of three widely-located study sites over the arid steppe lands in Algeria. The Simple Linear Model (SLM) and Support Vector Machine (SVM) were utilised as statistical learning techniques on data; firstly, from each study site separately, and secondly, from all study sites (pooled data). In all study sites, SVM improves R² with a mean of 4.5% and decreases the Root Mean Squared Error (RMSE) and Percentage of Error (PE), respectively, with 15.50 (kg DM ha−1) and 1.33% on average. In all cases, the SWIR-VIs outperforms the VNIR-VIs with an improvement rate of 40% of R² and an average reduction of 362.36 kg DM ha−1 and 25% of RMSE and PE, respectively. The principal main improvement was found to involve the pooled data-based model utilising normalised difference VI form, which combines OLI2(0.452–0.512 μm) with OLI7(2.107–2.294 μm), (R² = 0.840, p < 0.0005). [ABSTRACT FROM AUTHOR]

One species of the family Ctenodactylidae, the Common gundi, Ctenodactylus gundi, occupies a restricted area between the Saharan and Mediterranean domains where annual rainfall is between 50 and 400 mm. Its presence seems also conditioned by the vegetation, so its feeding ecology was investigated by the microhistological analysis of faeces collected in two stations (Baniane and Bazem) of the Aurès massif (Eastern Algeria) during two years from June 2015 to May 2017, and by the evaluation of the available food. The diet included a total of 34 plant species, 16 in Baniane and 20 in Bazem. Results show that in Baniane, Asteraceae were predominant with Artemisia herba-alba (relative abundance, A% = 33.13%), followed by Fabaceae with Argyrolobium uniflorum (A% = 20.32%) and Poaceae with Aristida sp. (A% = 14.95%). In Bazem, the most consumed plant species were Lamiaceae with Thymus ciliatus (A% = 42.77%) and Poaceae with Lolium rigidum (A% = 13.19%). Overall, C. gundi fed on a large number of plant species, and its diet appeared to be influenced more by the diversity than by the availability of vegetation. Seasonal variations in diet indicate that this rodent eats perennial vegetation throughout the year and opportunistically consumes annual plants to a lesser extent in the spring, with a certain time shifting between the two stations probably due to rainfall and temperature differences. [ABSTRACT FROM AUTHOR]

This study investigates the determining parameters of thermal comfort of office in an arid hot-arid environment of Bechar, located in the northwestern region of Algeria, in which the vertical walls of the room and the roof are subjected to solar irradiations and the floor is considered to be adiabatic. The solar flux is calculated by the ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) method. The predicted results are validated against the experimental results of the meteorological station of the ENERGARID research laboratory at the University of Bechar (Algeria). The characteristics of the ambient air flow are performed by using the computational fluid dynamics (CFD) software (Fluent). The flow fields, thermal fields, and humidity are investigated. An elaborated computer program (with Delphi language) is utilized to evaluate the temperature–humidity coupling as the most essential factors of the thermal comfort. A significant impact of dynamic temperatures and humidity on thermal comfort has been observed, especially in this hot-arid environment. Besides, a considerable effect of the flow velocity has been remarked. From the obtained results and to provide the best thermal comfort in such arid regions, the range of air velocity inside the building is recommended to be between 0.2 m·s−1 and 0.3 m·s−1. [ABSTRACT FROM AUTHOR]