Impact of climate change on the water resources of the Atbara River using novel hydrological models.

Rivers respond directly to climate change, as well as incorporating the effects of climate-driven changes occurring within their watersheds. In this research, climate change's impact on the Atbara River, one of the main tributaries of the Nile River, was studied. Various statistical methods of analysis were applied to study the basic characteristics of the climatic parameters that affect the discharge of the Atbara River. The three hydrological gauging stations on the Atbara River, namely, the Upper Atbara and Setit reservoirs, Khashm el-Girba reservoir, and Atbara Kilo 3 station, were included in the study. The correlation between the meteorological parameters and the hydrology of the Atbara River and the prediction of the future hydrology of the Atbara River Basin was determined. Many hydrological models were developed and tested to predict the hydrology of the river. Finally, forecasting for river hydrology was built. No significant trend was found in the precipitation in the study area. The developed model simulates the observed data with a high coefficient of determination ranging from 0.7 to 0.91 for the three hydrological gauging stations studied. Results predicted a slight decrease in river discharge in future years.

The developmental architecture of the crop of quail embryos (Coturnix coturnix): Morphometric, light and scanning electron microscopy.

The present study focused on the histogenesis of the crop in quail embryos. The developmental sequence was recorded from day 10 of incubation to the hatching day (17th day) by gross anatomy, morphometric analysis and by using light and scanning electron microscope (SEM). Grossly, the crop was distinguished as an enlarged pouch of the cervical oesophagus on the 12th day of incubation. Histologically, the development of the crop began on the 10th day of incubation. The muscularis mucosae was observed as a small, thin layer of myoblast cells on the 10th day, then it appeared as longitudinally arranged smooth muscle fibres with progression of the developmental age till hatching day. The submucosal layer was also observed on the 10th day, while the lamina propria, muscular layer (inner circular and outer longitudinal layers of smooth muscle fibre) and glandular primordia were detected on the 12th day. The epithelial cells of crop revealed affinity for PAS stain and AB-PAS on the 10th day of incubation till the 17th day, while the affinity for AB stain appeared on the 14th day of incubation. Additionally, the glandular cells showed the positive for AB, PAS and AB-PAS on the 12th day of incubation. SEM sections showed variable sizes of the openings of the oesophageal glands. In conclusion, the present study provided a detailed overview of the histogenesis of the crop in quail embryos.

Insight into land cover dynamics and water challenges under anthropogenic and climatic changes in the eastern Nile Delta: Inference from remote sensing and GIS data.

The destabilization of delta's worldwide due to climate change and human activities presents challenges in meeting the growing demands for freshwater and food. The Nile Delta in Egypt is a prime example of a vulnerable region facing various stressors. In order to preserve land and water resources, it is crucial to monitor the spatial and temporal changes in Land Use/Land Cover (LULC), shoreline, and Terrestrial Water Storage (TWS) in these vulnerable regions This study comprehensively investigates the dynamic changes in LULC and their associated water and soil responses in the Eastern Nile Delta under these combined impacts. To achieve this goal, a combination of remote sensing techniques utilizing Landsat (5, 8, and 9), and GRACE datasets, along with field observations and Geographic Information System (GIS) tools, was employed. Accordingly, shoreline changes show coastal erosion rates ranging from 5.28 to 34.92 m/year due to climate change-induced SLR, with continued inland movement predicted for the next 20 years. Moreover, the dynamic changes in urbanization and alterations in agricultural cover have considerable penalties for water demand. Analysis of GRACE data indicates a notable reduction in average TWS by 77.89 mm between 2002 and 2017, with an annual rate, estimated at -5.821 mm/year. Soil sampling in highly vulnerable areas confirms agricultural degradation attributed to elevated salinity levels, with EC values ranging from 3.60 to 190 ds/m. These finds provide valuable insights for stakeholders and policymakers, to make reliable strategies regarding water allocation, land use regulations, and climate change adaptation in the worldwide vulnerable deltas.

A comprehensive study on the arterial vasculature of the brain in water buffalo (Bubalus bubalis): Clinical correlates.

The present study was designed to provide a comprehensive analysis of the anatomical aspects of arterial blood vasculature in the water buffalo brains. Fifty cranial cavities of adult water buffaloes were opened via both the dorsal and ventral approaches and the arteries were exposed and photographed. The buffalo rostral epidural rete mirabile generally resembled that of large ruminants. The oculomotor, abducent and trigeminal nerves were intimately associated with the rostral rete. Similar to the majority of ruminants, the arterial circle of the brain was heart-shaped in buffalos and presented all collateral blood vessels as mentioned in the previous literature. The study further revealed that the cranial nerve roots were closely related to the arterial circle of the brain and could be used as indicators for differentiating various branches of the arterial circle of the brain. In addition to the usual variations of the arterial circle of the brain, a bihemispheric rostral cerebral artery along with an aplastic rostral cerebral artery were reported for the first time. The deviant behaviour of the rostral cerebral artery forms a baseline to study various clinical conditions of the blood vasculature in the buffalo brain. The rostral choroidal, middle cerebral and the caudal cerebral arteries constantly were emerged as single vessels without any variations. In conclusion, the anatomy of the arterial vasculature of the buffalo brain observed in the present study provided evidence of its morphological resemblance to other species of the Bovini tribe.

Morphology of the soft palate and palatine tonsil of the goat (Capra hyricus).

The present study was carried out to study the morphology of the goat's soft palate and palatine tonsil by gross anatomy, morphometry, light and scanning electron microscopy (SEM). Twelve heads of normal adult (18-24 months) apparently healthy goats of both sexes were collected from local commercial slaughterhouses in Qena Governorate, Egypt. The oral cavity was dissected, and samples were collected for both light and SEM. The soft palate of the goat formed the caudal continuation of the hard palate. It was relatively short, it extended from the level of the caudal border of the last upper molar tooth to terminate caudally against the base of the epiglottis. The oral mucous membrane of the soft palate was covered by non-keratinized stratified squamous epithelium. The lamina propria and submucosa contained connective tissue fibers, diffuse and nodular lymphatic tissue, striated muscle fibers, and a large number of mucous and serous palatine glands. By SEM, the ventral surface had several rounded openings occupied by flower-like structures. These openings represented the entrances to the palatine glands. The palatine tonsil was large and protruded from a fossa in the lateral wall of the oropharynx. It had 2-3 elongated irregular openings that lead to the underlying crypts. These crypts were well-developed and lined by non-keratinized stratified squamous epithelium. The epithelium of the tonsillar crypts directly covered lymphoid tissue and was infiltrated by lymphocytes. Tonsillar glands of pure mucous type were demonstrated. In conclusion, the study provides the basic morphological features of soft palate, as well as the palatine tonsil of the goat by gross observation, light and SEM. The palatine tonsils of goat were well-developed with extensive crypt system, suggesting their essential role in the immunological response against antigens that enter through the oral cavity. The current findings may be useful to understand the role of the palatine tonsil in immunity and disease pathogenesis. RESEARCH HIGHLIGHTS: The study reported the basic morphological features of soft palate and palatine tonsil of goat. The ventral surface of the soft palate had several rounded openings occupied by flower-like structures. The palatine tonsils of goat were well-developed with extensive crypt system. The findings might help to understand the role of the palatine tonsil in immunity and disease pathogenesis.

The inhibitive action of 2-mercaptobenzothiazole on the porosity of corrosion film formed on aluminum and aluminum-titanium alloys in hydrochloric acid solution.

2-Mercaptobenzothiazole (2-MBT) in a solution of 0.5 M HCl is an effective corrosion inhibitor for aluminum and aluminum-titanium alloys. Tafel polarization and electrochemical impedance spectroscopy (EIS) were employed to assess this heterocyclic compound's anticorrosive potential and complementary by scanning electron microscope (SEM) and calculating porosity percentage in the absence and presence of various inhibitor concentrations. Inhibition efficiency (IE%) was strongly related to concentration (10-6-10-3 M). Temperature's effect on corrosion behavior was investigated. The data exhibited that the IE% decreases as the temperature increases. An increase in activation energy (Ea) with increasing the inhibitor concentration and the decrease in the IE% value of the mentioned compound with raising the temperature indicates that the inhibitor molecules are adsorbed physically on the surface. Thermodynamic activation parameters for Al and Al-Ti alloy dissolution in both 0.5 M HCl and the inhibited solution were calculated and discussed. According to Langmuir's adsorption isotherm, the inhibitor molecules were adsorbed. The evaluated standard values of the enthalpy ([Formula: see text], entropy ([Formula: see text] and free energy changes ([Formula: see text] showed that [Formula: see text] and [Formula: see text] are negative, while [Formula: see text] was positive. The formation of a protective layer adsorbed on the surfaces of the substrates was confirmed with the surface analysis (SEM). The porosity percentage is significantly reduced in the inhibitor presence and gradually decreased with increasing concentration. Furthermore, the density functional theory (DFT) and Monte Carlo (MC) simulations were employed to explain the variance in protecting the Al surface from corrosion. Interestingly, the theoretical findings align with their experimental counterparts. The planarity of 2-MBT and the presence of heteroatoms are the playmakers in the adsorption process.

Effect of di(n-butyl) phthalate on the blood-testis barrier during puberty onset.

Di(n-butyl) phthalate (DBP) is considered a substance of serious concern because of its reproductive toxicity and endocrine-disrupting properties. Exposure to DBP causes morphological and functional changes in the male reproductive system of birds and mammals. However, there are no detailed reports on the effects of DBP on the Sertoli cell and junctional complexes of the blood-testis barrier (BTB) in birds. The present study investigated dose-related ultrastructural changes in Sertoli cells and junctional complexes of the BTB in adult Japanese quail (Coturnix coturnix japonica) exposed to DBP prior to puberty. A total of 25 Japanese quail were used for the study. Exposure to DBP doses of 50, 200 and 400 mg DBP/kg/d caused dose-related ultrastructural changes in junctional complexes including dilation and separation, while disruption of cytoplasmic membranes and mitochondria was observed in Sertoli cells. There was a significant difference in the sum of vacuoles, vacuole diameter, nuclear width, nuclear length, nuclear area, sum of damaged spherical mitochondria, width of elongated mitochondria and the sum of damaged elongated mitochondria among the five treatment groups (p Ë‚ 0.05). Prepubertal exposure to DBP at doses of 50, 200 and 400 mg DBP/kg/d for 30 days led to adverse effects in the adult male Japanese quail reproductive system by inducing structural changes in the Sertoli cells and junctional complexes. Such changes might disrupt the BTB and potentially interfere with spermatogenesis. Results indicated that the Sertoli cell is sensitive to DBP exposure and might be an important cellular target for DBP-induced testicular toxicity.

Use of Melatonin/Decorticotomy and Autogenous Bone Graft in Induced 1-Wall Defect.

PURPOSE: This study was designed to investigate the effect of intramarrow penetration (IMP) and 1% melatonin (MLN) gel on the remodelling process of autogenous bone graft (ABG) in an induced 1-osseous wall defect model. METHODS: Sixty-four intrabony induced mandibular defects were created on the distal side of premolars-P1, P2, P3, and P4 (on each side)-in 8 beagle dogs. A ligature-induced periodontitis was initiated in each defect. Defects were then divided into 4 equal groups. Group I was treated with open-flap debridement (OFD) alone, group II was treated with OFD/ABG, group III was treated with OFD/IMP/ABG, and group IV was treated with OFD/ABG/IMP/1% MLN gel. The study parameters were bone fill, histologic analysis, and immunohistochemical evaluation of endothelial nitric oxide synthase (eNOS) expression at 2-week (2W) and 8-week (8W) time intervals. RESULTS: At 8W, significant differences were revealed amongst all groups regarding the amount of bone fill and eNOS expressions (P < .001). Bone fill percentages were 55.5%, 22.3%, 16.8%, and 0% in groups IV, III, II, and I, respectively. eNOS expressions were 1.68 ± 0.06, 8.43 ± 0.04, 16.80 ± 0.17, and 1.97 ± 0.07 in groups IV, III, II, and I, respectively. The favourable results were in line with group IV. CONCLUSIONS: According to these preliminary results, defects treated by ABG augmented with IMP and 1% MLN gel revealed a greater amount of bone fill and reduced eNOS expression. This combination is therefore highly suggested as an adjunct to ABG.

Development and application of equilibrium optimizer for optimal power flow calculation of power system.

This paper proposes an enhanced version of Equilibrium Optimizer (EO) called (EEO) for solving global optimization and the optimal power flow (OPF) problems. The proposed EEO algorithm includes a new performance reinforcement strategy with the Lévy Flight mechanism. The algorithm addresses the shortcomings of the original Equilibrium Optimizer (EO) and aims to provide better solutions (than those provided by EO) to global optimization problems, especially OPF problems. The proposed EEO efficiency was confirmed by comparing its results on the ten functions of the CEC'20 test suite, to those of other algorithms, including high-performance algorithms, i.e., CMA-ES, IMODE, AGSK and LSHADE_cnEpSin. Moreover, the statistical significance of these results was validated by the Wilcoxon's rank-sum test. After that, the proposed EEO was applied to solve the the OPF problem. The OPF is formulated as a nonlinear optimization problem with conflicting objectives and subjected to both equality and inequality constraints. The performance of this technique is deliberated and evaluated on the standard IEEE 30-bus test system for different objectives. The obtained results of the proposed EEO algorithm is compared to the original EO algorithm and those obtained using other techniques mentioned in the literature. These Simulation results revealed that the proposed algorithm provides better optimized solutions than 20 published methods and results as well as the original EO algorithm. The EEO superiority was demonstrated through six different cases, that involved the minimization of different objectives: fuel cost, fuel cost with valve-point loading effect, emission, total active power losses, voltage deviation, and voltage instability. Also, the comparison results indicate that EEO algorithm can provide a robust, high-quality feasible solutions for different OPF problems.

Junctional complexes of the blood-testis barrier in the Japanese quail (Coturnix Coturnix japonica).

This study investigated the developmental changes in the adherens junctions, gap junctions, as well as tight junctions forming the blood-testis barrier (BTB) in Japanese quail (Coturnix Coturnix japonica) testis. Testicular tissue from pre-pubertal, pubertal, adult, and aged Japanese quail were examined by immunohistochemistry and transmission electron microscopy (TEM). The tight junction proteins claudin-3, claudin-11, occludin and zonula occludens-1 (ZO-1), were generally localised in the cytoplasm of Sertoli cells, spermatogonia, and spermatocytes of pre-pubertal, pubertal, some adult birds. The adherens junction protein E-cadherin had a similar distribution pattern. During pre-pubertal development, the gap junction protein connexin-43 (Cx43) was only localised between Leydig cells in the testicular interstitium. However, TEM revealed the presence of gap junctions between cells of the seminiferous epithelium as early as the pre-pubertal stage. Furthermore, TEM confirmed the presence of tight and adherens junctions in the seminiferous epithelia of all age groups. The findings of this study document age-related differences in the immunolocalisation and intensity of the junctional proteins and the ultrastructure of the junctional complexes forming the BTB in quail testes. Additionally, the junctional complexes forming the BTB in the Japanese quail are well established prior to puberty. This study provides baseline information for the future evaluation of pathological changes in the BTB of avian species at different developmental stages.

Effect of chitosan and curcumin nanoparticles against skeletal muscle fibrosis at early regenerative stage of glycerol-injured rat muscles.

INTRODUCTION: Chitosan and curcumin are natural products that have a wide range of beneficial effects including wound healing. However, their high molecular weight and poor water solubility limit their applications. AIMS: Therefore, the current study aims to evaluate the effects of chitosan (Cs) and curcumin (Cn) nanoparticles (NPs) on fibrosis and regeneration of glycerol-injured muscle. METHODS: Muscle injury was induced by intramuscular injection of glycerol into the tibialis anterior muscle of rats. Cs-NPs and Cn-NPs were administered at different doses intraperitoneally after injury. Injured muscles were collected at day 7 after injury, and muscle fibrosis and regeneration were assessed. RESULTS: The present results revealed that Cs-NPs and Cn-NPs treatment significantly decreased fibrosis index and increased the average myotube diameter with shifting of the distribution of myotube diameters towards larger diameters in a dose-dependent manner. Immunohistochemical analysis revealed that Cs-NPs and Cn-NPs treatment significantly decreased the number of CD-68+ cells and Col-1+ area. Results showed that Cn-NPs had a higher protective effect, in the form of attenuating muscle fibrosis and inflammation, and enhancing muscle regeneration, than that of Cs-NPs. CONCLUSIONS: To our knowledge, this is the first study to document the effects of Cs-NPs in injured muscles. The results of study might be a novel approach to attenuate muscle fibrosis in humans using curcumin and chitosan nanoparticles.

Comparative craniometric measurements of two Canid species in Egypt: the Egyptian red fox and the Egyptian Baladi dog.

The Egyptian red fox (Vulpes vulpes aegyptiaca) and Egyptian Baladi dog (Canis familiaris) are two members of the Family Canidae that are widely distributed in Egypt. The skulls of different Canid species vary greatly in their size and shape; therefore, they can be used as a tool to study the evolution and evolutionary history of these animals. The craniometric measurements are crucial for species identification and determination of the specific sites for nerve blocks. The present study compared the craniometric measurements of the red fox and Baladi dog skulls by measuring 47 parameters on each skull and calculation of 8 indices. The red fox skull had significantly lower values of 41 craniometric measurements (approximately 87% of the measurements done), including skull length, width, and height, cranial length and width, palatal and mandibular length, and dental measurements. In contrast, the red fox had significantly higher values of only 3 measurements (approximately 6% of the measurements done) including the tympanic bulla measurement. While only three skull measurements did not differ significantly between the red fox and dog. Statistics revealed that domestic dog had significantly higher values of foramen magnum and palatine indices, and significantly lower value of nasal index than those of red fox. The present work reported variations in the gross and craniometric measurements of skull between the red fox and dog. The measured cranial parameters of both adult animals provide valuable information that can be used in ecological studies, comparative anatomy, and clinical veterinary sciences.

Electronic cigarette exposure causes vascular endothelial dysfunction due to NADPH oxidase activation and eNOS uncoupling.

We recently reported a mouse model of chronic electronic cigarette (e-cig) exposure-induced cardiovascular pathology, where long-term exposure to e-cig vape (ECV) induces cardiac abnormalities, impairment of endothelial function, and systemic hypertension. Here, we delineate the underlying mechanisms of ECV-induced vascular endothelial dysfunction (VED), a central trigger of cardiovascular disease. C57/BL6 male mice were exposed to ECV generated from e-cig liquid containing 0, 6, or 24 mg/mL nicotine for 16 and 60 wk. Time-dependent elevation in blood pressure and systemic vascular resistance were observed, along with an impairment of acetylcholine-induced aortic relaxation in ECV-exposed mice, compared with air-exposed control. Decreased intravascular nitric oxide (NO) levels and increased superoxide generation with elevated 3-nitrotyrosine levels in the aorta of ECV-exposed mice were observed, indicating that ECV-induced superoxide reacts with NO to generate cytotoxic peroxynitrite. Exposure increased NADPH oxidase expression, supporting its role in ECV-induced superoxide generation. Downregulation of endothelial nitric oxide synthase (eNOS) expression and Akt-dependent eNOS phosphorylation occurred in the aorta of ECV-exposed mice, indicating that exposure inhibited de novo NO synthesis. Following ECV exposure, the critical NOS cofactor tetrahydrobiopterin was decreased, with a concomitant loss of its salvage enzyme, dihydrofolate reductase. NADPH oxidase and NOS inhibitors abrogated ECV-induced superoxide generation in the aorta of ECV-exposed mice. Together, our data demonstrate that ECV exposure activates NADPH oxidase and uncouples eNOS, causing a vicious cycle of superoxide generation and vascular oxidant stress that triggers VED and hypertension with predisposition to other cardiovascular disease.NEW & NOTEWORTHY Underlying mechanisms of e-cig-induced vascular endothelial dysfunction are delineated. e-cig exposure activates and increases expression of NADPH oxidase and disrupts activation and coupling of eNOS, leading to a vicious cycle of superoxide generation and peroxynitrite formation, with tetrahydrobiopterin depletion, causing loss of NO that triggers vascular endothelial dysfunction. This process is progressive, increasing with the duration of e-cig exposure, and is more severe in the presence of nicotine, but observed even with nicotine-free vaping.

Role of cytoglobin in cigarette smoke constituent-induced loss of nitric oxide bioavailability in vascular smooth muscle cells.

Cytoglobin (Cygb) has been identified as the major nitric oxide (NO) metabolizing protein in vascular smooth muscle cells (VSMCs) and is crucial for the regulation of vascular tone. In the presence of its requisite cytochrome B5a (B5)/B5 reductase-isoform-3 (B5R) reducing system, Cygb controls NO metabolism through the oxygen-dependent process of NO dioxygenation. Tobacco cigarette smoking (TCS) induces vascular dysfunction; however, the role of Cygb in the pathophysiology of TCS-induced cardiovascular disease has not been previously investigated. While TCS impairs NO biosynthesis, its effect on NO metabolism remains unclear. Therefore, we performed studies in aortic VSMCs with tobacco smoke extract (TSE) exposure to investigate the effects of cigarette smoke constituents on the rates of NO decay, with focus on the alterations that occur in the process of Cygb-mediated NO metabolism. TSE greatly enhanced the rates of NO metabolism by VSMCs. An initial increase in superoxide-mediated NO degradation was seen at 4 h of exposure. This was followed by much larger progressive increases at 24 and 48 h, accompanied by parallel increases in the expression of Cygb and B5/B5R. siRNA-mediated Cygb knockdown greatly decreased these TSE-induced elevations in NO decay rates. Therefore, upregulation of the levels of Cygb and its reducing system accounted for the large increase in NO metabolism rate seen after 24 h of TSE exposure. Thus, increased Cygb-mediated NO degradation would contribute to TCS-induced vascular dysfunction and partial inhibition of Cygb expression or its NO dioxygenase function could be a promising therapeutic target to prevent secondary cardiovascular disease.

Evaluation of the online learning of veterinary anatomy education during the Covid-19 pandemic lockdown in Egypt: Students' perceptions.

The sudden shift of veterinary anatomy teaching from traditional to online mode during the coronavirus disease 2019 (Covid-19) pandemic lockdown was a major challenge used for the first time in Egyptian veterinary medical schools. This study aimed to evaluate the students' perspectives regarding the shift of veterinary anatomy teaching to online mode during the lockdown in Egypt. A total of 502 students from all veterinary medical schools in Egypt (n = 17) answered the questionnaire. The results revealed that nearly two-thirds of students felt enthusiastic about studying anatomy online during the pandemic. Moreover, approximately 63% of students were satisfied with the provided learning materials, 66% were able to understand anatomy using the online learning system during the lockdown period, 67% were comfortable with technological skills during their online study, and 47% believed that online learning of anatomy could replace face-to-face teaching. Therefore, despite the problems associated with the emergency switch to remote teaching, it appears to be a suitable alternative in teaching veterinary anatomy in Egyptian universities during this pandemic crisis in Egyptian universities. Moreover, the study provided several measurements to overcome the common problems associated with this challenging method for future application, such as providing three-dimensional virtual tools and electronic devices with either free or low-priced Internet packages, and measuring students' understanding before and after each lecture. This is the first study to solicit the early students' feedback regarding the emergency shift to online veterinary anatomy teaching which might help decision-makers in Egypt for future implementation of online learning of veterinary anatomy.

Ontogeny of the testicular excurrent duct system of male Japanese quail (Coturnix japonica): A histological, ultrastructural, and histometric study.

The testicular excurrent duct system undergoes several physiological and morphological changes during the reproductive stage or breeding season in mammals, birds, and reptiles. Studies on normal age-related histomorphological changes in the excurrent duct system of Japanese quails (Coturnix japonica) remain unreported, despite the extensive use of this bird as an avian model in research studies. The current study investigated the histological, ultrastructural, and histometric changes in the testicular excurrent duct system of the Japanese quail during three reproductive stages, namely prepubertal, pubertal, and adult. Simple squamous to low cuboidal cells formed the epithelia of the rete testis in prepubertal and pubertal birds, while in adult birds the lining was low cuboidal to cuboidal. In pubertal and adult birds, the nonciliated Type I epithelial cells of the proximal efferent duct displayed a subapical endocytotic apparatus comprising coated pits, coated apical tubules, and endosomes. There was a significant increase (p ≤ .001) in epithelial heights of all ducts of the excurrent duct system in the mature, sexually active, adult birds when compared to the other age groups. The luminal and tubular diameters, and the cross-sectional areas of efferent ducts and the epididymal duct unit increased significantly (p ≤ .001) with age. It is concluded that the morphology and morphometry of the excurrent ducts of the testis of the Japanese quail change as birds mature.

Correlation between computed tomography, magnetic resonance imaging and cross-sectional anatomy of the head of the guinea pig (Cavia porcellus, Linnaeus 1758).

The current work aimed to study the anatomical features of the guinea pig's head by two medical imaging techniques: computed tomography (CT) and magnetic resonance imaging (MRI), and their correlation with the anatomical cross-sectional images. Six adult healthy guinea pigs were used in the present study. Two heads were imaged by CT scanner and then by MRI. The examined heads were cut sagittally and transversely, and two skulls were macerated. The anatomical features were identified on the anatomical sections and compared with the tomographic and MRI images obtained. Data were presented as three-dimensional reconstructed images of the head. In addition, representative combinations of the sagittal and transverse anatomical sections and the corresponding CT scans and MRI images were also presented. Reconstruction of CT images enabled the visualization of different bony structures and airways of the guinea pig head. In addition, skull bones were easily visualized on CT scans, while different parts of the brain were identified on MRI images. Air cavities could be identified by their different contrast on the CT scans and their low intensity on MRI images. The study showed that guinea pig had poorly developed paranasal sinus system represented by rostral and caudal maxillary sinuses. On the contrary, the guinea pig had two tympanic bullae: a small dorsal and a large ventral bulla. In conclusion, this study provides one of the first investigations that uses the multislice CT scans and MRI to study the guinea pig's head and their correlation with the corresponding anatomical sections.

Cytoglobin has potent superoxide dismutase function.

Cytoglobin (Cygb) was discovered as a novel type of globin that is expressed in mammals; however, its functions remain uncertain. While Cygb protects against oxidant stress, the basis for this is unclear, and the effect of Cygb on superoxide metabolism is unknown. From dose-dependent studies of the effect of Cygb on superoxide catabolism, we identify that Cygb has potent superoxide dismutase (SOD) function. Initial assays using cytochrome c showed that Cygb exhibits a high rate of superoxide dismutation on the order of 108 M-1 ⋅ s-1 Spin-trapping studies also demonstrated that the rate of Cygb-mediated superoxide dismutation (1.6 × 108 M-1 ⋅ s-1) was only ∼10-fold less than Cu,Zn-SOD. Stopped-flow experiments confirmed that Cygb rapidly dismutates superoxide with rates within an order of magnitude of Cu,Zn-SOD or Mn-SOD. The SOD function of Cygb was inhibited by cyanide and CO that coordinate to Fe3+-Cygb and Fe2+-Cygb, respectively, suggesting that dismutation involves iron redox cycling, and this was confirmed by spectrophotometric titrations. In control smooth-muscle cells and cells with siRNA-mediated Cygb knockdown subjected to extracellular superoxide stress from xanthine/xanthine oxidase or intracellular superoxide stress triggered by the uncoupler, menadione, Cygb had a prominent role in superoxide metabolism and protected against superoxide-mediated death. Similar experiments in vessels showed higher levels of superoxide in Cygb-/- mice than wild type. Thus, Cygb has potent SOD function and can rapidly dismutate superoxide in cells, conferring protection against oxidant injury. In view of its ubiquitous cellular expression at micromolar concentrations in smooth-muscle and other cells, Cygb can play an important role in cellular superoxide metabolism.

Producing Heavyweight High-Performance Concrete by Using Black Sand as Newly Shielding Construction Material.

Experimental work was carried out to study new fine aggregate shielding construction materials, namely black sand (BS). The BS effect on the mechanical, durability, and shielding characteristics of heavyweight high-performance concrete (HWHPC) was evaluated. This study aimed at improving various HWHPC properties, concertedly. Fifteen mixtures of HWHPC were made, with various variables, including replacing 10% and 15% of the cement with fly ash (FA) and replacing normal sand by BS at various contents (15%, 30%, 45%, 60%, 75%, and 100%). The test specimens were subjected to various exposure conditions, including elevated temperatures, which ranged from 250 °C to 750 °C, for a duration of 3 h; magnesium sulfate (MS) exposure; and gamma-ray exposure. The effects of elevated temperature and sulfate resistance on concrete mass loss were examined. The results revealed that BS is a promising shielding construction material. The BS content is the most important factor influencing concrete compressive strength. Mixes containing 15% BS demonstrated significantly better strength compared to the control mixes. Exposure to 250 °C led to a notable increase in compressive strength. BS showed a significant effect on HWHPC fire resistance properties, especially at 750 °C and a significant linear attenuation coefficient. Using 10% FA with 15% BS was the most effective mixing proportion for improving all HWHPC properties concertedly, especially at greater ages.