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This paper presents motion planning strategies that assure stable hovering for a transformable unmanned aerial vehicle (UAV) throughout its transformation. The considered multirotor UAV consists of multiple links equipped with rotors. The UAV can transform its structure by changing the lateral joint angle connecting these links. We first introduce the concept of hoverability, which assures static hovering with a linear state feedback controller. Because the hoverability can be evaluated quantitatively by utilizing a convex hull yielded by the positions of rotors, we propose motion planning methods that leverage the hoverability to achieve transformation while guaranteeing stable hovering with desired margin. As the hoverability can be investigated geometrically without analyzing the dynamics of UAVs, the proposed method can be readily employed for a wide class of transformable UAVs, including the one in which clockwise and counterclockwise rotors are not arranged alternately. The proposed motion planning is designed to secure the specified threshold for hoverability and avoid interferences between links or rotors. We then present two types of costs for motion planning: one minimizes the transformation duration, and the other maximizes the hoverability during the transformation. The proposed motion planning is optimized via Dijkstra's algorithm and demonstrated in simulation. [ABSTRACT FROM AUTHOR]

Pollutants in an environment can have long-term implications for the species living there, resulting in local adaptations with implications for their genetic structure. Heavy metal pollutants infiltrate soils and groundwater, bioaccumulate in food webs, and negatively impact biota. In this study, we investigated the degree to which the genetic structure and variability of the slender green-winged grasshopper (Aiolopus thalassinus (Fabricius) (Orthoptera: Acrididae)) were impacted by heavy metal pollution and distance. We used the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) method to examine the genetic variability of populations in 3 heavy metal-polluted and 3 unpolluted locations across varying geographical distances in Egypt. The heavy metal concentrations of cadmium, copper, lead, and zinc were measured from the grasshopper tissue and soils. Sixty-nine unique and polymorphic bands were produced by 4 primers. Cluster and principal component analyses separated the populations inside and outside Cairo into 2 main branches, which were further divided into smaller branches corresponding to their geographical regions. We found no differences in the Shannon genetic diversity index between populations or with increasing heavy metal concentrations in either the soil or the grasshopper tissue. Our results showed a greater genetic variation among populations than between populations within the same location, indicating populations within locations were less differentiated than those between locations. The moderate correlation between genetic similarity and spatial distance suggests geographical isolation influenced grasshopper population differentiation. Based on the RAPD analysis, environmental pollutants and geographical distances impact the A. thalassinus population structure, potentially restricting gene flow between sites even at small spatial scales. [ABSTRACT FROM AUTHOR]

Simple Summary: Spogostylum ocyale (Wiedemann 1828) is a robust species of bee fly (family Bombyliidae), known to be a larval ectoparasitoid as well as an important flower pollinator. This species has disappeared from many of its historic habitats due to substantial changes in floral and faunal compositions in recent years. The current and future distributions of the parasitoid in the Middle East region was predicted using the Maximum entropy model (Maxent). The model performance was satisfactory and revealed a good potential distribution for S. ocyale featured by the selected factors. The results show that the distribution of S. ocyale is mainly affected by the temperature. Coastal regions, with warm summers and cold winters, were high to medium in suitability. Future scenarios predict a progressive decline in the extent of suitable habitats with global warming. These findings lead to robust conservation management measures in current or future conservation planning. Spogostylum ocyale (Wiedemann 1828) is a large robust species of bee fly (family Bombyliidae), known to be a larval ectoparasitoid as well as an important flower pollinator as an adult. This species has become extremely rare or has disappeared from many of its historic habitats due to substantial changes in floral and faunal compositions in recent years. Climate change and urbanisation, together with other anthropogenic activities, may be to blame for these changes. Distribution modelling based on environmental variables together with known occurrences is a powerful tool in analytical biology, with applications in ecology, evolution, conservation management, epidemiology and other fields. Based on climatological and topographic data, the current and future distributions of the parasitoid in the Middle East region was predicted using the maximum entropy model (Maxent). The model performance was satisfactory (AUC mean = 0.834; TSS mean = 0.606) and revealed a good potential distribution for S. ocyale featured by the selected factors. A set of seven predictors was chosen from 19 bioclimatic variables and one topographic variable. The results show that the distribution of S. ocyale is mainly affected by the maximum temperature of the warmest period (Bio5) and temperature annual range (Bio7). According to the habitat suitability map, coastal regions with warm summers and cold winters had high to medium suitability. However, future scenarios predict a progressive decline in the extent of suitable habitats with global climate warming. These findings lead to robust conservation management measures in current or future conservation planning. [ABSTRACT FROM AUTHOR]

Leafhoppers (family: Cicadellidae) are among the most common plant sap-sucking pests, causing damage to wild and agronomic plants worldwide. The current paper aims to assess the zoogeography, diversity and population dynamics of the leafhopper species in an agricultural land converted ecosystem. Twenty species (two identified only to the genus level) belonging to 17 genera, 10 tribes, and three subfamilies were collected from Toshka Region, Aswan Governorate, Egypt, in 2020. The most common cicadellid species was Orosius albicinctus, representing 46.7% of the total catch. Low values of species richness and diversity were measured for leafhopper species as compared with those reported in our recent study carried out in Alexandria and Qena governorates. In sum, conversion of any natural ecosystem to agricultural land uses may cause declines in insect diversity. However, desert conversion may increase the diversity pattern of some insect pests. Analysis of the zoogeographic affinities of the leafhopper species from Toshka Region indicated a closer affiliation to the Palaearctic Region (35%) than any other region. Most leafhopper populations exhibited a unimodal seasonal pattern and were abundant in hot and dry months (May–September). The abundance of some leafhopper species correlated positively with temperature (seven species) and negatively with relative humidity (nine species). Six of these species correlated with both variables. This study is the first to investigate leafhopper communities in a converted ecosystem of Toshka Depression, Western Desert. [ABSTRACT FROM AUTHOR]

Leafhoppers constitute one of the largest and most common groups of plant sap-sucking pests found in wild and agricultural habitats. They cause damage to plants directly through feeding and oviposition or indirectly through transmission of dangerous plant pathogens. The present study aims to list, assess and compare the diversity and temporal fluctuations of the cicadellid species associated with different cultivated agronomic crops in two governorates (Qena and Alexandria), representing two different Egyptian ecological zones. By light trapping, 33 species (four species identified only to the genus level) belonging to 22 genera, 12 tribes and 4 subfamilies were collected from six field sites throughout the year 2018. The most common leafhopper species was Empoasca decipiens, composing 51.3% of the total individuals collected, while the other 32 species encompassed 48.7%. Although a significant difference was found in the species richness of leafhoppers between the two governorates, none was found for abundance, species diversity or evenness. A cluster analysis derived from similarity of species composition of cicadellid communities showed a clear grouping of the study sites in each ecological zone. Furthermore, significant differences were found between the community structures in Qena and Alexandria governorates (analysis of similarities [ANOSIM], R = 0.722). A similar population pattern was observed for both governorates. Generally, the density of nearly all cicadellids showed unimodal seasonal patterns with one peak in midsummer (July or August). Spearman's rank correlation analysis showed significant positive relationships between abundance of cicadellids and temperatures in both governorates; however, no correlation with humidity was found. This is the first faunal and systematic study conducted on a diverse range of leafhopper species collected from different cultivated agronomic crops in two Egyptian governorates. [ABSTRACT FROM AUTHOR]

Excessive accumulation of trace metal in soil represents a growing environmental problem posing severe risks to biota, humans and ecosystems. Concentrations of Cd, Pb, Cu and Zn were determined in soil, as well as in representatives of some trophic levels in the terrestrial food webs in two Egyptian agroecosystems; El-Manzala (a rural area located in the northeast of the River Nile Delta) and El-Tebbin (an industrial area located in South Cairo). Representatives of trophic levels included arthropods, amphibians, reptiles, birds and small mammals. Metal concentrations were determined in the leaves of wild plants, bodies of arthropods and livers of vertebrates. Levels of metals in the soil, plants and most animal species were higher in El-Tebbin than El-Manzala. Minimal concentrations of metals were detected more often in plants and in the cattle egret, whereas maximum values were common in the soil, amphibians and a mantid. Accumulation of metals was more frequent in arthropods and other taxa at lower trophic levels of food webs, suggesting that the transfer of metals along the vertebrate food web may be of relatively minor importance. However, of all the metals examined, only Pb was bioaccumulated to any appreciable extent in some of the higher trophic levels. A significant increase in liver mass and relative liver mass of the Norway rat from the polluted site was observed. [ABSTRACT FROM AUTHOR]

Background: Although breast cancer management has generally improved, there is still a standing challenge represented by the triple-negative breast cancer whose recurrence is highly frequent, disease-free survival shortened, and the overall survival is extremely poor. The Aim of Work: Compare between the total response rate of using gemcitabine/cisplatin versus paclitaxel/gemcitabine regimens to treat the metastatic triple-negative breast cancer cases. Materials and Methods: A random clinical trial method carried out on patients with metastatic triple-negative breast cancer who attended to the Department of Oncology and Nuclear Medicine, Suez Canal University, in 2016/2017. A random assignment used to allocate patients who are qualified to: Group (A) to receive cisplatin /gemcitabine (cisplatin 75 mg/m² on day 1; gemcitabine 1000 mg/m² on days 1 and 8) or Group (B) to receive paclitaxel/gemcitabine (paclitaxel 175 mg/m² on day1; gemcitabine 1000 mg/m² on days 1 and 8) every 3 weeks for eight cycles at maximum or until the development of disease progression or the intolerable toxic effect. Results: Cases of triple-negative breast cancer were 144 (20.9%) and those of metastatic triple-negative breast cancer were 110 (15.98%). Within a-12-month follow-up period, the total response rate of Group (A) was significantly higher than Group (B) (69.1% versus 47.3%, respectively). In addition, the median disease-free survival of Group (A) was significantly higher than that of the Group (B) (mean 7.18 versus 5.49 respectively). Conclusion: Cisplatin/gemcitabine can be used alternatively, even a superior regimen to paclitaxel/gemcitabine, for patients with metastatic triple-negative breast cancer. [ABSTRACT FROM AUTHOR]

The concentrations of Cd, Cr, Cu, Fe, Ni, Pb, and Zn were studied in soil, plants, three grasshopper species (Aiolopus thalassinus (Fabricius, 1781), Calephorus compressicornis (Latreille, 1804), and Acrotylus patruelis (Herrich-Schäffer, 1838)), and a mantid (Miomantis paykullii Stål, 1871), to estimate the scale of spatial influence of a point pollution source, to investigate metal bioaccumulation up the soil-plant-grasshopper-mantid food chain, and to assess these insects as ecological bioindicators. Plant, insect, and soil sampling was undertaken simultaneously from grass margins of an arable farmland near an industrial complex in Al-Tebbin. Correlation analyses revealed a pollution gradient, with samples closest to the industrial activities having the highest concentrations of heavy metals. Sigmoid curves indicated that the influence radius of the industrial zone for heavy metal contamination in soil, plants, and grasshoppers was in the range of 3.0-4.0 km. The average concentrations of Cd, Cr, Cu, Fe, Ni, Pb, and Zn in the three grasshopper species were 4.9, 4.0, 73.9, 210, 5.2, 12.0, and 224.2 mg/kg, respectively, while those in the predaceous mantid were 9.0, 7.9, 106.4, 400, 14.8, 23.0, and 463.7 mg/kg, respectively. The metal content did not increase from soil to grasses, but at plant-primary consumer level, Cd, Cu, Pb, and Zn were biomagnified, and, in general, all metal concentrations increased with an increase in the trophic level (i.e., secondary consumer). In light of this site-dependent accumulation of heavy metals and their biomagnification patterns, the investigated acridids can be considered bioindicators of Cd, Cu, Pb, and Zn pollution. [ABSTRACT FROM AUTHOR]

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This article studies the complex mass and energy interactions between the reformer and the reduction furnace in an iron plant based on Midrex technology. The methodology consists in the development of rigorous first principle models for the reformer and the reduction furnace, in addition to models for auxiliary units such as heat recuperator, scrubber and compressor. In this regard, a one-dimensional heterogeneous model for the catalyst tubes which takes into account the intraparticle mass transfer resistance was developed for the reformer unit, while the furnace was modelled with bottom-firing configuration. As for the reduction furnace, the mathematical model was based on the concept of shrinking core model. The furnace was modelled as a moving bed reactor taking into consideration the effects of water gas shift reaction, steam reforming of methane and carburisation reactions. The model was first validated using data from a local iron/steel plant and was then simulated to determine key output variables such as bustle gas temperature, degree of metalisation, carbon content, ratio of hydrogen to carbon monoxide, reductants to oxidants ratio and required compression energy. The effects of key input parameters on the performance of the plant were studied. These parameters included recycle ratio, scrubber exit temperature, injected oxygen flow rate, flow rate of natural gas after reformer, to transition zone, to reformer and to cooling zone. Useful profiles were compiled to illustrate the results of the sensitivity analysis. These results may serve as guidelines for a further optimisation of the plant. [ABSTRACT FROM AUTHOR]

The monthly density of the sand fly, Phlebotomus Papatasi Scopoli (Diptera: Psychodidae), was monitored during 2009 at Burg El-Arab, a rural district located close to the Mediterranean coast of Egypt. The number of annual generations and the efficacy of microbial control by the entomopathogenic fungus, Metrahizium anisopliae (Metsch.) Sorok (Ma79), were determined in the laboratory under atmospheric conditions, simulating those of the animal shelters in the study area. We used two collecting techniques; CDC light traps and oiled paper traps, to quantify sand fly density inside houses mad in the open field. Adult flies exhibited a seasonal range from April to December. The seasonal pattern was bimodal, with one peak in July and the second one in October. Calculations of the correlation coefficient (r) revealed a significant role of temperature and relative humidity in the monthly abundance of the sand flies in the study area. P. papatasi colony completed seven annual generations under semifield conditions, but the mean developmental time of each immature stage and the mean total duration of development from egg to adult for each generation varied according to the prevailing temperature. The longest generation time was observed in winter (the mean ± SD was 118 ± 11.70 d), and the shortest one occurred at the highest temperatures in summer (the mean ± SD was 25.21 ± 2.04 d). In microbial control studies, the entomopathogenic fungus, M. anisopliae, was used at 15 x 108 spores/g food as a standard dose against the second-instar larvae ofP. papatasi at the different seasons during 2009. Mortality reached 100% in winter and decreased to 56.0% as the prevailing temperature increased during the summer season. [ABSTRACT FROM AUTHOR]

Wastewater irrigation is often practiced in arid regions, which can increase the chance of heavy metals contaminating the agricultural system. This contamination poses risks to both the environment and human health. This research looked into how cadmium (Cd), lead (Pb), copper (Cu), and zinc (Zn) move through a food chain involving soil, plants, and arthropods. The study was conducted in El-Gabal El-Asfar, Egypt, comparing treated and untreated wastewater irrigation areas. Six soil-irrigated sites and one reference site were sampled for soil, alfalfa (Medicago sativa), two grasshopper species (Aiolopus thalassinus and Calephorus compressicornis), and a wolf spider (Hogna ferox). The samples were analyzed for their heavy metal content. Metal concentrations in all components of the wastewater irrigated system were significantly higher compared to the reference site. The wolf spider and the soil contained the highest levels of Cd, Pb, and Cu, while the greatest concentrations of Zn were found in the spider and grasshoppers. Despite limited transfer from soil to plant, trace elements biomagnified within the terrestrial food chain, specifically from grasshoppers to wolf spiders. The correlation analysis of metal levels between soils, plants, and arthropods in the present study reflects its transfer across the trophic levels. It suggests that dietary intake is the main source of metal accumulation in arthropods. The present study, therefore, quite clearly indicated the possibility of heavy metal biomagnification in terrestrial food chains of wastewater-irrigated agroecosystems. Continuous monitoring and management of such systems are advocated to avoid environmental and public health risks., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)