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The Digital Elevation Models (DEMs) are used to represent the topographic surface of the earth as it is used in many applications. Nowadays, many free DEMs are available online. This study aims to assess the accuracy of six free DEMs. This research uses the GPS observations to determine the elevation stations in the study area by using the Post-Processing Kinematic (PPK) technique and compares these elevations against the elevations computed at the same stations by using six free online Digital Elevation Models (DEMs): SRTM 1 Arc-Second, ASTER 1 Arc-Second, NASADEM 1 Arc-Second, SRTM 3 Arc-Second, GTOPO30, and ALOS PALSAR 12.5 m to find the best results from the free DEMs. The elevations of all stations of different data sources were calculated using the geoid model EGM96. The results indicate that the DEMs that give the best results in this study are obtained from NASADEM 1 Arc-Second, where (RMSE is 2.99 m, and the SD is 2.97 m), and SRTM 3 Arc-Second, where the (RMSE is 3.70 m, and the SD is 3.53 m).

Penta-glasses with a 59B2O3–29SiO2–2LiF–( $$10-x$$ ) ZnO– $$x$$ TiO2 composition with the melt-quench techniques were prepared. X-ray diffraction was used to examine the nature of fabricated glasses. The changes in the structure of fabricated glasses were studied by Fourier-transform infrared spectroscopy spectra. The molar volume of fabricated glasses reduces as the density increases. The mechanical characteristics of these glasses were evaluated. Besides, for the studied glasses, Phy-X/PSD and XCOM program were used to investigate the radiation shielding efficiency. These glasses were found to have an abnormal attenuation, structural, and density relationship. Glasses' mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half-value layer (HVL), tenth value layer (TVL), and effective atomic number (Zeff) were designed to simulate gamma photon energies ranging from 0.015 to 15 meV. MAC values determined with Phy-X/PSD and XCOM were compared and were observed in good agreement with the other.

Glasses with the chemical composition of 52B2O3 – 12SiO2–26Bi2O3 – (10 − x)TiO2 - xY2O3, :(0 ≤ x ≤ 10) prepared using the melt-quench method. The goal of this study is to investigate the structural, mechanical, and radiation shielding characteristics of these samples. XRD analysis has explored the nature of the glass system. Molar volume obtained reduced while the density denotes increased in the present system. As the molar volume decrease inter-ionic distance, polaron radius, inter-nuclear distance, and Y-Y separation of the investigated glasses decreased. The mechanical characteristics depend on the glass structure of the current glasses sample. Ultrasonic velocities and elastic moduli (experimental and theoretical) for these glasses obtained they were observed to get enhanced. The radiation shielding efficiency was investigated by Phy-X/PSD software. The mass attenuation coefficient, mean free path, half-value layer, tenth value layer, and effective atomic number of glasses have been designed to simulate gamma photon energies between 0.015 and 15 MeV.

To formulate multiparticulate controlled-release alginate-gelatin (AL-GL) beads in order to modify gliclazide (GLZ) release rate. AL-GL beads were prepared using different glutaraldehyde concentrations and dried using either air or freeze-drying method. For comparison, calcium alginate beads (AL-beads) were prepared at different temperatures. Drug incorporation efficiency, beads swelling%, drug release rate, and kinetics in gradient conditions (USP Apparatus-4) were studied. Selected AL-GL beads, as a test formulation (T), were in-vivo compared with Diamicron® 80 mg conventional tablet (R). AL-beads curing temperature was inversely proportional to GLZ incorporation efficiency and directly proportional to beads swelling%. GLZ release from AL-beads was slow in 0.1 N HCl and very fast in pH 7.4. In case of AL-GL beads, GLZ incorporation efficiency and swelling% were inversely proportional to glutaraldehyde concentration. AL-GL beads showed zero-order release of GLZ for up to 11 h. Scanning electron microscope (SEM) images of the freeze-dried beads showed a highly porous surface. Differential scanning calorimetry (DSC) and Fourier transform infra-red (FT-IR) studies indicated an interaction between alginate and gelatin due to crosslinking, while FT-IR indicated the absence of chemical interaction with GLZ. The relative bioavailability (T/R) was 97.57, 138.34, and 143.53%, for Cmax, AUC0–72, and AUC0–∞, respectively. Tmax of T was significantly higher than R. AL-GL beads could represent promising delivery systems for modulating GLZ release rate and minimizing the variation in its absorption.

Nanocomposites films based on Poly Vinyl Pyrrolidone/Chitosan (PVP/Chitosan) filled by Vanadium pentoxide nanoparticles (V2O5 NPs) have been produced via solution casting method. Vanadium pentoxide nanoparticles were scattered direct in the blend of PVP/Chitosan by one-potential laser ablation technique. The main purpose in using Vanadium pentoxide nanoparticles is to modify the structural, optical, and electrical characterization of PVP/Chitosan composite. The complexation between Vanadium pentoxide nanoparticles and PVP/Chitosan has been approved via XRD and FTIR-ATR analyses. The average size of V2O5 was 20.5 nm. After the scattering by vanadium pentoxide nanoparticles, AC conductivity improved. The values of dielectric constant and dielectric lose decreased as the frequencies enhanced. At lower frequency, greater values of dielectric constant and dielectric lose have been detected due to the mobile charges inside the polymeric backbone. The fabricated PVP/Chitosan/V2O5 NPs films could be suggested for electrical and optoelectronic applications.

In vitro and in vivo studies of gliclazide (GLZ)-loaded freeze-dried alginate-gelatin (AL-GL) beads were carried out, aiming to modify its oral bioavailability. Crosslinked freeze-dried GLZ AL-GL beads (particle size: 1.5- and 3.0-mm) were prepared. In vitro evaluation of GLZ AL-GL beads included SEM, DSC, FT-IR, and release rate study in gradient media. In vivo study was single-dose (4 mg/kg), randomized, parallel-group design, two-treatment (T: test GLZ AL-GL beads and R: reference product Diamicron® 30-mg MR tablet) conducted in 96 healthy rats. Each group was subdivided into 2 sub-groups (G1 and G2) having different blood sampling schemes for up to 72 h. Assessment of level A in-vitro-in-vivo correlation (IVIVC) model was carried out. AL-GL beads successfully increased GLZ release rate compared to R. GLZ percent released (Q4h) was 109.34, 86.85, and 43.43% for 1.5-mm and 3.0-mm beads and R, respectively. DSC analysis confirmed the interaction of AL-GL via crosslinking. No chemical interaction of GLZ has occurred as proved by FT-IR. Relative bioavailability (T/R) for AUC0-∞ was 132.45% for G1 and 146.16% for G2. No significant differences between T and R in the primary pharmacokinetic parameters were determined. Tmax values were found to be earlier in the case of G1 than those of G2. A secondary absorption peak of GLZ was clearly detected in the case of R while its sharpness was minimized in T. High IVIVC was established, and hence, the proposed in vitro release model perfectly correlated with the in vivo study. The current study design might be a platform to enable panoramic view for GLZ variability in vivo.

A new fusion of geophysical scanners is developed for detection of the near-surface buried objects, such as iron pipes, pieces of metal, and rocks. The new fusion was built up in a cart that integrates three kinds of geophysical instruments including an EM-61 metal detector, magnetometer, and OhmMapper. For the new system, we have innovate an electric control unit and adapted all the original connection cables to efficiently and simultaneously collect the electromagnetic field, magnetic intensity, and apparent resistivity on the surface of ground. We also modified and complement DOS-based computer programs to automatically measure the three kinds of data, record the surveying positions, and transfer the data from the system to a host computer for integration of the mapping images. The new system has been tested at a synthetic field site where five different objects are previously buried. The experimental results show successes in mapping these near-surface targets and prove that the new system archives saving surveying time, obtaining comprehensive data, reducing human interventions and number of human operators. It may become a new efficient and effective tool of geophysical exploration for detection of the near-surface buried objects.

The present investigation is the first in Egypt to give histomorphological data about Heterosaccus dollfusi, a rhizocephalan parasitic barnacle of the brachyuran crab Charybdis longicollis, collected from the eastern Mediterranean coast of Egypt at shallow depths (10–20 m). The structure of the mature externa and its male organs are essential for perception of both the taxonomy and reproductive biology of these specialized parasites. We use scanning electron microscopy and histological methods coupled with morphological description to investigate the anatomy of mature externa. The mature externa is distinguished by a visceral mass which comprises the ovary, paired colleteric glands, paired male receptacles and paired receptacle ducts. Attention is focused on the developmental stages of male organs and/or tracing of spermatozoa after settlement of male cypris implantation of the trichogon during fertilization process. For the first time, the lateral tube that connects the left male receptacle with the right, smaller receptacle was observed in sagittal section and illustrated in the diagrammatic figure of male organs. This tube is probably the generator of sperm ribbons. As well, the existence of the spermatozoa inside the lumen of this connecting tube may indicate their free movement between the two receptacles. Moreover, strips of sperm that drag from the sperm ribbon ball, and surround the developing ovules can also be seen in the mantle cavity.

Poly (ethyl methacrylate) (PEMA) - cellulose acetate propionate (CAP) blend film was prepared using the cast technique. A Q-switched Nd: YAG laser beam with a wavelength of 266 nm, a pulse duration of 10-ns, a repetition rate10 Hz and 0.018 J/cm2 fluence was used to irradiate the prepared film. The optical absorption of pristine and irradiated sample was studied within 200–500 nm wavelength region. The absorbance increases with laser irradiation time over the full wavelength region which is attributed to an increase of the crosslinking network. Examining Tauc plots revealed a transition of the direct allowed type with optical energy gap value of 4.92 eV for the pristine blend film which has decreased to 4.30 eV after laser irradiation for 90 min. The refractive index, finesse coefficient, dielectric function, Brewster, and critical angles demonstrated dispersion in the 200–500 nm wavelength range.

A series of thiazole, pyridine and benzylidene derivatives derived from thiophene scaffold have been synthesized. The antitumor evaluation of the newly synthesized products against four cancer cell lines, namely breast carcinoma (MCF-7), liver carcinoma (HepG2), colon carcinoma (HCT-116) and prostate carcinoma (PC3), indicated that the thiazole derivative 11b showed remarkable activity against all cell lines with LC50 values of 18.3, 2.5, 7.5 and 7.6 µM, respectively. Cytotoxicity toward normal cell lines was also investigated and indicated that compound 21c displayed remarkable potency against PC3 with LC50 values of 7.1 µM and showed weak inhibition of normal cell lines at (GI %) of 41.2 % and thus could be considered as an important lead compound for potential application in anticancer chemotherapy. Brine shrimp lethality assay of the most active compounds was carried out to detect possible cytotoxicity effects and indicated that highly active compound, 21c, is not harmful. The X-ray crystallographic analysis of compounds 3 and 11b was obtained thus establishing with certainty the proposed structures in this work. The synthesized compounds were also screened for their free radical scavenging activity. Hydrazino–thiazole derivatives 15 and 16 showed remarkable antioxidant activity with IC50 values of 60.9 and 61.9 μg ml−1, respectively.

The ability of eight flavonoids to react with the biologically relevant reactive nitrogen species, nitric oxide, peroxynitrite, and nitrous acid were investigated in vitro, for the first time. All the investigated flavonoids were found to be potent reactive nitrogen and oxygen species scavengers and resulted in a significant inhibition of 3-nitrotyrosine (3-NT) formation in a dose-dependent manner. All the IC50s were found at the μM level. The results reveal that, the presence of C5–OH and C4’–OH, in the flavonoid skeleton, enhanced the anti-nitrosative activity. The absence of the C2=C3 double bond and/or C4-carbonyl group resulted in slight decrease of the anti-nitrosative activity. However, the presence of C6- and/or C3’-methoxy groups together with C4’–OH dramatically decrease the inhibition capacity. Especially the free hydroxyl groups at 3’ and 4’ of the catechol containing ring B flavonoids as well as both hydroxyl groups at C3 and C5 are necessary for better antioxidant activity. The absence of both C3–OH and/or C3’–OH groups resulted in a remarkable decrease in the antioxidant activity. The cytotoxicity results indicate that the investigated flavonoids are safe to be used up to a concentration of 100 μM and may be utilized as promising sources of therapeutics.

The present paper describes a submarine survey using the acoustic discrimination system QTC VIEW (Series V) as an exploratory tool to adjust final route alignment of a new pipeline. By using acoustic sound survey as an exploratory tool described in this paper to adjust final route alignment of a new pipeline to minimize the environmental impact caused and ultimately to avoid any mitigation measures. The transmission pipeline extended from the shore line of Abu-Qir Bay, on the Mediterranean Sea in Egypt, out to 70 nautical miles at sea (60 m water depth). Four main surface sediment types were defined in the study area, namely fine sand, silty sand, silt and clay. Results of the acoustic classification revealed four acoustic classes. The first acoustic class corresponded to fine sand, absence of shell debris and very poor habitats characteristics. The second acoustic class is predominant in the study area and corresponds to the region occupied by silt. It is also characterized by intermediate diversity of macrobenthic invertebrate community which is mainly characterized by polychaeta. The third acoustic class is characterized by silt to silty clay. It is characterized by a high diversity of macrobenthic invertebrate community which is mainly polychaeta with an intermediate diversity of gastropoda and bivalvia. The final acoustic class is characterized by clay and high occurrence of shell debris of gastropoda, bivalvia and polychaeta.

Persistent or de novo left ventricular hypertrophy (LVH) is a risk factor for cardiovascular diseases and congestive heart failure following renal transplantation (RT). Our aim was to determine the associations and impact of persistent LVH on RT outcome.We included 72 live-donor renal allograft recipients with mean age of 28.5 years who had evidence of LVH at time of transplantation and had stable functioning grafts 1 year after transplantation. Cardiac status of all recipients was assessed before transplantation and at 1 year after transplantation by echocardiography. Recipients were subdivided into two groups according to persistence or regression of LVH 1 year after transplantation. The first group included 33 patients who had persistent LVH. The second group included 39 patients in whom LVH had regressed (control group). Both groups were closely followed for 10 years.Univariate analysis showed that persistent LVH 1 year after RT was significantly associated with high serum creatinine, higher incidence of medical infection, and acute and chronic rejection. Chronic rejection and infection were the only valid associations on multivariate logistic regression analysis. Patient and graft survival were significantly lower in the persistent LVH group (P = 0.012).Persistent LVH may be associated with higher incidence of medical infection and chronic rejection that worsen the prognosis for renal transplant recipients.

Posttransplantation anemia (PTA) frequently occurs. We aimed to assess the prevalence of anemia at 6 months of transplantation in patients under different protocols of immunosuppression, and to determine the impact of anemia on long-term patient and graft survival. We included 832 renal transplant recipients who were categorized at 6 months according to hemoglobin (Hb) level into two groups: the first group, with Hb >13 g/dl in males and >12 g/dl in females (group I, 385 cases); and the second group, with Hb

Systemic lupus Erythematosus (SLE) is a rheumatic autoimmune disease characterized by multisystem organ involvement and by high titers of auto antibodies against several nuclear and cytoplasmic antigens. Numerous abnormalities of the cytokine network have been described in patients suffering from SLE. However the role of cytokines in different organ involvement is not yet well defined.To determine if levels of Interlukin-6 (IL-6) and Tumor necrosis factor (TNF-alpha) correlate with SLE disease activity in Egyptian SLE patients and more specifically with hematological involvement.Levels of TNF-alpha and IL-6 in serum samples from sixty individuals (40 with Systemic lupus Erythmatosus and 20 healthy controls) were determined and renal biopsies were obtained from SLE patients.Levels of TNF-alpha and IL-6 were higher in SLE patients with active compared with inactive hematological disease. Further analysis showed that this association was dependent on inverse correlation (P=0.017, r=-0.49) for IL-6 and (P=0.76, r=-.243) for TNF-alpha. The mean level of TNF-alpha and Il-6 was (766.95+/-357.82 pg/ml) and (135.4+/-54.23 pg/ml) respectively for patients with active disease while it was (314.01+/-100.87 pg/ml) and (47.33+/-18.61 pg/ml) for those with inactive disease and (172.7+/-39.19 pg/ml) and (21.15+/-10.99 pg/ml) for the healthy control group respectively. The difference was statistically significant (P=0.002). We found significant positive correlations between TNF-alpha and IL-6 and the SLE Disease Activity Index (SLEDAI) score. (r=+0.743 and +0.772 respectively).Raised level of Il-6 and TNF-alpha may influence the development of anemia in Egyptian patients with Lupus Nephritis.

The value of intravenous immunoglobulin (IVIG) and simvastatin as potential modalities for the treatment of sensitized patients was evaluated by testing the efficacy of these agents on a relatively large cohort of adult hemodialysis patients (11) who were waiting for renal allotransplantation at our center. The patients had persistently positive crossmatches with their living related donors and a panel reactive antibody titer of more than 20%. All patients received IVIG (500 mg/kg per day on alternate days for a total of six doses); panel reactive antibody (PRA) titer and crossmatch testing were carried out after each dose and before each subsequent one. Two months after the last dose, eight patients received simvastatin (20 mg/day) for a period of 2 months; PRA titer and crossmatch testing were carried out every two weeks. Only four patients showed an insignificant reduction of PRA activity (P = 0.36); no patient attained a negative crossmatch. Simvastatin also resulted in an insignificant reduction of anti-human leukocyte antigen (HLA) antibodies in three patients (P = 0.32). We propose that IVIG or simvastatin alone can not effectively inhibit preformed anti-HLA antibodies to allow successful renal transplantation. Further trials on the use of IVIG and simvastatin with other modalities of treatment to desensitize these patients may be warranted.