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Background and Aim: Upper respiratory tract infections are common in horses and can be caused by a variety of pathogens, mainly Streptococcus equi subsp. equi, which are a significant equine pathogen causing major health issues as well as financial losses to the equine industry. This study aimed to determine the prevalence of Streptococcal bacteria in equines in Egypt, and characterize vancomycin-resistant S. equi subsp. equi phenotypically and genotypically. Materials and Methods: S. equi subsp. equi was isolated from internal nares of horses. All strains were confirmed by polymerase chain reaction-based detection of Streptococcus genus-specific 16S rRNA, sodA and seeI genes. Antibiotic susceptibility was determined phenotypically using the disk diffusion method. Genotypic detection of antibiotic resistance genes was performed by analyzing as β-lactamase resistance (blaZ), tetracycline resistance (tetK), vancomycin resistance (vanA), and chloramphenicol resistance (fexA). Results: Eight streptococcal isolates were confirmed as S. equi subsp. equi. The genotypic characterization of antibiotic resistance showed resistance to vanA and tetK, with a frequency of 87.5% and 12.5%, respectively, while the frequency of sensitivity was 100% for blaz gene and fexA gene. Conclusion: In this study, we assessed vancomycin-resistant S. equi subsp. equi from equines suffering from respiratory manifestation in Egypt.

Attention deficit hyperactivity disorder (ADHD) represents a mysterious neuropsychiatric alarming concern due to indefinite etiopathogenesis among children. Notably, the studies which investigated the correlation between ADHD and parasitic infections are insufficient. Therefore, this research aimed to assess the correlation between ADHD and some tissue dwelling and intestinal parasitic infections in children. The study was conducted on 200 children, including 100 children suffering from ADHD (Group I) and 100 healthy children as a control group (Group II). All caregivers fulfilled predesigned sociodemographic form and Conners parent rating scale (CPRS-48) questionnaire. Blood samples were collected to determine hemoglobin level as well as relative eosinophilic count. The presence of anti-Toxoplasma IgG and anti-Toxocara IgG in serum by Enzyme-Linked Immunosorbent Assay (ELISA) was further investigated. Also, micronutrients as zinc, iron, and copper levels were measured. Schistosoma antigen was investigated in urine samples. Stool samples were subjected to direct wet smear, concentration technique and modified Ziehl-Neelsen (MZN) staining for coccidian parasites detection. Cryptosporidium parvum, Giardia lamblia and Entamoeba histolytica antigens were investigated in stool samples. Group I expressed more liability to sociodemographic risk factors, decreased levels of Hb, iron, zinc, and copper with statistically significant difference (P < 0.001). Comparison between Group I and Group II regarding the detected parasitic infections exhibited statistically significant difference except Schistosoma antigen positivity which expressed no statistical significance. The present study concluded that the parasitic infections with their consequences are potential risk factors in children with ADHD indicating that their early diagnosis and treatment may help in ADHD prevention.

Background: Primary hyperparathyroidism (pHPT) caused by a single benign parathyroid adenoma is a common endocrine disorder that is affected by regional differences. Living in different geographical regions reveals differences in the laboratory results and pathological findings, but studies on this subject are not sufficient. The article focuses on biochemical and pathological effects of geographical differences in parathyroid adenoma. In addition, the present study seeks to elaborate on treatment methods and effectiveness of screening in geographical area of Bulgaria and Turkey. Method: In this prospective study, 159 patients were included from 16 centres. Demographic characteristics, symptoms, biochemical markers and pathologic characteristics were analysed and compared between 8 different regions. Results: Patients from Turkish Black Sea had the highest median serum calcium (Ca) level, whereas patients from Eastern Turkey had the lowest median serum phosphorus (P) level. On the other hand, there was no significant difference between Ca, parathormone (PTH) and P levels according to regions. Patients from Eastern Turkey had the highest adenoma weight, while patients from Bulgaria had the lowest adenoma weight. The weight of adenoma showed statistically significant differences between regions (p < 0.001). There was a correlation between adenoma weight and serum PTH level (p = 0.05) and Ca level (p = 0.035). Conclusion: This study has provided a deeper insight into the effect of the regional differences upon clinicopathological changing and biochemical values of pHTP patients with adenoma. Awareness of regional differences will assist in biochemical screening and treatment of this patient group. (c) 2021 Asian Surgical Association and Taiwan Robotic Surgery Association. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).

High radioactivity in a relatively saline confined aquifer water in different locations of the Disi area (South East of Jordan) was reported by some authors who recommended further investigation on the impact of that water on irrigated soils. Five well water samples (jointly used for irrigation and drinking) and 28 surface and subsurface soil samples from five profiles were collected from that area for the purpose of this study. Selected mineralogical, chemical, and physical properties of the soil samples were determined. Mineralogical compositions of the 28 soil samples were identified using x-ray diffraction, x-ray fluorescence, and ICP-MS techniques. Determination of activity concentrations of

We investigated the polarization-dependent terahertz optical conductivity of rubber compounds with carbon black (CB) fillers under cyclic deformation to detect deformation-induced changes of the internal CB structure in a contactless manner. It is clearly observed that the conductivity during the unloading is reduced from that during the loading at the same draw ratios. To interpret this hysteresis of the conductivity, we perform theoretical calculation based on the effective medium theory. Comparing with the calculation, we attribute the hysteresis of the conductivity to the reduction of the anisotropy of the CB aggregates, which might result from the deformation-induced rupture of them.

Meat samples of various animal species have been obtained from Giza Governorate's butcher shops, common retail markets, veterinary faculties, Zoo and hospitals. Physical, bacteriological, and molecular analysis was carried out on the meat samples. Physical examination showed that typical and untypical meat differed. Bacteriological examination showed the highest TCC was found in horse meat while the least was in goat meat. The total count of S. aureus was the highest in donkey and dog whilst the least in pork meat. As for E.coli, donkey meat was the highest while buffalo and mutton meat were the lowest. The highest total Listeria monocytogenes and Salmonella Species count were in horse, donkey, rat and dog meat but zero in the other species examined. Multiplex-PCR targeting partial-length of cytochrome b (cyt b) gene of mitochondrial DNA (mtDNA) was used for the discovery of adulteration of beef meat with chicken, pork, dog, cat and rat tissue. It showed high specificity in differentiating the six animal species meat. The study points out the importance of taking serious steps to control species meat adulteration that may lead to transmission of severe foodborne diseases and more studies need to be implemented to apply new and easy meat adulteration detection protocols.

Despite extensive vaccination campaigns, Newcastle disease virus (NDV) remains endemic in many countries worldwide, and factors that contribute to this failure include mismatched vaccines, partial immunization, and poor husbandry practices. In order to overcome the problem of genetic divergence between circulating field strains and vaccine strains, we saponin-adjuvanted an Egyptian field strain and assessed its safety and immunogenicity in chickens. Immunization of chickens with the vaccine followed by challenge with a velogenic reference strain revealed the potential of the saponin-adjuvanted vaccine to induce a strong immune response that resulted in complete protection of chickens. Importantly, in vaccinated chickens, virus shedding was abolished, providing an added advantage over the currently available commercial live-attenuated and inactivated vaccines, which are unable to prevent shedding. A histopathological investigation demonstrated that the vaccinated chickens had less-severe lesions than challenged unvaccinated and mock-vaccinated chickens. We propose using this formulation as an alternative and improved NDV vaccine platform that can be exploited to control disease not only in Egypt but also in other disease-endemic countries.

The structural and magnetic properties of doped ferrite Zn 0.3 Cu 0.7 Fe 1.5 Ga 0.5 O 4 have been studied by means of the neutron diffraction method at high pressures up to 4.7 GPa and in temperature range 300–425 K. By increasing the temperature and the pressure, a gradual suppression of the magnetic moments of iron ions in both A and B crystallographic sites was observed. This effect corresponds to a magnetic phase transition from the ferrimagnetic state to paramagnetic one. The lattice parameters, interatomic bond lengths and angles, magnetic moments of iron ions as functions of temperature and pressure were obtained. Upon compression, the magnetic ordering temperature of studied ferrite decreases with a large pressure coefficient dT c / dP = −19(1) K × GPa −1 .

WOS: 000451246700003, PubMed ID: 31149275, Objective. Ectopic posterior pituitary gland (EPP) is usually characterized by an abnormal pituitary stalk and hypoplasia of the anterior hypophysis. The genetic mechanisms involved in the development of EPP remain uncertain. The aim of this study is to determine whether mutations in the three genes, PROP-1, LHX2, and POU1F1, are associated with the risk for and the characteristics of EPP. Methods. In the Endocrinology Outpatient Clinic of "Dr. Behcet Uz" Children's Hospital, 27 patients with EPP were submitted to sequencing analyses of the PROP-1, LHX2, and POU1F1 genes. Results. Growth hormone, thyrotropin, corticotropin, gonadotropin, and vasopressin deficiency were observed in 22 (81.5%), 23 (85.2%), 17 (63%), 14 (51.9%), and two (7.4%) patients. Thirteen patients (48.1%) presented with hyperprolactinemia. Fourteen patients (51%) had a history of birth dystocia, and 12 cases (42.1%) had a history of breech presentation. Central nervous system abnormalities included five cases with corpus callosum agenesis, one case with schizencephaly, and one case with Chiari type 1 malformation. We identified a homozygous p.S109* mutation in exon 2 in one male patient with EPP and two different PROP] gene polymorphisms (A142T or c.109+3 G>A polymorphism) in thirteen patients. Conclusions. Our results suggest that PROP1 gene abnormalities might explain the genetic mechanisms involved in the development of EPP.

Nano-sized Gram-negative bacterial outer membrane vesicles possess unique structural and immunostimulatory effects that could be exploited to regress tumors by alerting the host immune system and reversing the immunosuppressive tumor microenvironment. The current study was conducted to investigate the antitumor activity of the outer membrane vesicles (ST-OMVs) of Salmonella Typhimurium ATCC 14028, in vitro in human colorectal carcinoma (HTC116), breast cancer (MCF-7), and hepatocellular carcinoma (HepG2) cell lines and in vivo in Ehrlich solid carcinoma-bearing mice model either as a mono-immunotherapy or as an adjuvant to a commonly used conventional chemotherapy. In addition, we investigated the safety of ST-OMVs. Adult Swiss albino female mice with transplanted Ehrlich solid carcinoma were treated with either ST-OMVs, paclitaxel or a combination of both. Tumor volume, growth inhibition rate, quantitative RT-PCR of Bax and VEGF genes expression, histopathology and immune-expression of caspase-3, Beclin-1, CD49b and Ki-67 were all analyzed. Our results showed that ST-OMVs significantly decreased tumor volume, significantly increased tumor growth inhibition rate, up-regulated the immunohistochemical expression of caspase-3, Beclin-1, and CD49b (enhanced recruitment of NK cells). Furthermore, ST-OMVs down-regulated the expression of Ki-67, increased Bax gene expression and decreased VEGF gene expression as detected by qRT-PCR analysis. Histologically, ST-OMVs promoted apoptosis, decreased tumor invasion and mitotic activities. Moreover, ST-OMVs showed a remarkable cytotoxic activity in various investigated in vitro cancer cell lines. Our findings demonstrate potential antitumor activity of ST-OMVs that might be used as a promising safe antitumor immunotherapy or an adjuvant to conventional chemotherapeutic drugs, resolving some of their problems.

In this chapter, we introduce a comprehensive study of the effect of both particle size and doping (Ga, Zn, and Sm) on the structural and magnetic properties of bulk and nanonickel ferrites. Different techniques; X-ray powder diffraction, Mossbauer effect spectroscopy and vibrating samples magnetometer were mainly utilized to deeply investigate the structural and magnetic properties of the prepared samples. Using different preparation techniques, different Ni-ferrite samples with different particle sizes were obtained. X-ray powder diffraction confirmed the formation of single-phase nano-Ni-ferrite, whereas, Mossbauer effect and vibrating samples magnetometer measurements captured the impact of reduced particle size on the cation distribution and magnetism. Then, Ni1 − xZnxFe1.49Ga0.5Sm0.01O4 (0 ≤ x ≤ 0.5) bulk ferrites were systematically studied. In this case, the effect of doping was examined. Later, ultrasmall NiFe1.99Sm0.01O4 and Ni1 − xZnxFe1.49Ga0.5Sm0.01O4 (x = 0, 0.3, 0.5) nanoparticles were prepared and investigated to combine the effect of the doping and the reduced particle size. Indeed, the obtained results confirmed the possibility of modifying the magnetic properties of Ni-ferrite by controlling the particle size and by introducing different transition metals and rare earths to its unit cell.

Polycrystalline Ni 1−x Zn x Fe 1.49Ga 0.5Sm 0.01 O 4 (0≤x≤0.5) spinel ferrite powders were prepared using standard ceramic method. Structural and magnetic properties of the sintered samples were investigated using X-ray powder diffraction, Mossbauer effect spectroscopy, and vibrating sample magnetometer. X-ray analysis confirmed the formation of single phase cubic spinel ferrites for all samples. The cation distribution obtained from the Mossbauer effect measurements suggested that Sm 3+ ions substituted iron in the octahedral [B] site and increase the magnetism in the studied samples. On the other hand, Ga 3+ ions replaced iron in both tetrahedral (A) sites and octahedral [B] sites. For x≤0.3, Zn 2+ ions are introduced to (A) sites and unusually for higher Zn content, x>0.3, they distribute in both (A) and [B] sites and suppress magnetism in this system. The cation distribution obtained from the Mossbauer effect measurements explains well the change in the values of both lattice parameter (a) and the saturation magnetization (M s ).

The ferrite system, Ni1−x Zn x Ga0.5Fe1.5O4 (x ranges from 0.0 to 0.5 in steps of 0.1), has been synthesized by a solid-state reaction technique. Single-phase cubic spinel structure was confirmed with X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) results. The effect of introducing zinc in the unit cell on the electrical properties was investigated in the ranges 102–105 Hz and 300–600 K of frequency and temperature, respectively. Semiconducting behavior over all studied ranges of frequency and temperature was observed. This behavior is attributed to the cation–anion–cation interaction, which is most predominant at B-sites in these samples. Variation of the universal exponents with temperature indicates the presence of a correlated barrier hopping (CBH) mechanism. The determined transition temperature T C was found to decrease with increasing the compositional parameter x.

Cyclophosphamide (CTX) has been used to precondition recipient hosts before adoptive T cell therapy to tumor. The aim of the present study was to analyze the host cellularity changes resulting from different doses and timing of CTX administration. To address this aim, Ehrlich ascites carcinoma (EAC)-bearing mice (5×105cells/mouse) were intraperitoneal injected with 2 or 4 mg/mouse CTX either on day 1 or 7. The results revealed a significant decrease in the number of the tumor cells at 4 mg/mouse CTX on day 1 with an induction of 99% (11.6×106 cells/µl) death of the EAC cells. On day 1 post-EAC cells inoculation, there was a significant increase in the absolute number of splenocytes in EAC-bearing mice at 2 and 4 mg/mouse CTX. The absolute number of leukocytes, lymphocytes and monocytes in EAC-bearing mice non-significantly increased at 2 mg/mouse CTX on day 7 and at 4 mg/mouse CTX on day 1 and 7. Additionally, the absolute number of neutrophils was significantly increased at 2 mg/mouse CTX on day 7 and non-significantly increased at 4 mg/mouse CTX on day 7. The results indicate that: 1) the anti-tumor effect of CTX is a dose- and time-dependent, 2) the use of high dose of chemotherapy is preferable to anti-tumor adoptive cell therapy since it induces higher anti-tumor effects with less lymphopenia.

Background The pathogenesis of post-transplantation erythrocytosis (PTE) is not well understood and appears to be multifactorial. Our hypothesis in this study was that several factors, including toxicity of calcineurin inhibitor, immunologic factors, and chronic allograft nephropathy, can trigger local tissue hypoxia in peritubular interstitium, which is where production of erythropoietin (EPO) takes place. This local interstitial tissue hypoxia can cause an increase in renal EPO production, which induces the development of PTE. Methods This cross-sectional study included 15 renal transplant recipients, in whom polycythemia developed after kidney transplantation, with elevated hematocrit level to >51%. Forty-eight age- and gender-matched renal transplant recipients with normal hematocrit level were included as the renal transplant control group. In addition, 13 age- and gender-matched healthy subjects were also included as the healthy control group. We used urine hypoxia-inducible factor-2 alpha (HIF-2α) levels to evaluate whether there is local tissue hypoxia in renal allograft. HIF-2α levels were measured by double antibody sandwich enzyme-linked immunosorbent assay (ELISA). Serum EPO and insulin-like growth factor-1 (IGF-1) levels were also measured. Results HIF-2α levels were significantly lower in the polycythemia group than the other two groups, but there was no significant difference between the healthy control group and the renal transplant control group with regard to HIF-2α levels. There was no significant difference among the 3 study groups in terms of levels of serum EPO and IGF-1. Conclusion Local tissue hypoxia in renal allograft does not seem to play an important role in the development of PTE.

Mn

Single-phase spinel ferrite Ni 1−x Zn x Ga y Fe 2−y O 4 with (0.0≤x≤0.5) and y=0.5 samples were synthesized using solid-state reaction technique. These ferrites were investigated using X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and Mossbauer effect (ME) spectroscopy. XRD patterns confirmed the formation of single-phase cubic spinel ferrites for all samples. Lattice parameter was found to decrease with the introduction of Ga 3+ in NiFe 2 O 4, and then to increase with the increasing of Zn 2+ content x. ME measurements illustrated a strong dependence on the zinc concentration. The cation distribution calculated from the ME spectra at room temperature indicated that the Ga 3+ ion substituted iron in both octahedral B and tetrahedral A- sites. Zn 2+ ions firstly introduced in A- site, and for higher x, they distribute in both B- and A- sites. VSM measurements indicated that the change in the value of saturation magnetization can be explained using the cation distribution obtained from ME measurements. The coercivity values can be interpreted on the basis of magneto-crystalline anisotropy.

Background: Couching, an ancient procedure for cataract surgery, is unfortunately still being practiced in many developing countries. There are several reports of couching in adult populations; however, literature is sparse on its occurrence in children. Case report: We report a case of a 10-year-old boy who had bilateral couching on account of congenital cataracts due to presumed congenital rubella syndrome. The patient had initially presented to our clinic during neonatal period and was scheduled for surgery. Unfortunately, surgery was not performed due to various reasons which were either patient related or health system related. He represented to the eye clinic 6 years post-couching with complaints of poor vision. Conclusion: This report aims to highlight the fact that couching is, indeed, being performed on children’s eyes, especially as a consequence of inefficiencies in the eye healthcare delivery system.

In this paper, Mg0.5Zn0.5-Cu(x)Fe2O4 ferrites nanoparticles were synthesized by facile co-precipitation route and characterized in detail in terms of their structural, electrical and magnetic properties as a function of Cu concentration. The prepared samples have cubic spinel phase as confirmed by X-ray diffraction patterns. The decrease of the lattice constant and increase of X-ray density indicate the solubility of Cu ions in the spinel lattice. The AC conductivity measurements between 300 K and 773 K at different frequencies 1 KHz up to 1 MHz, showed two different behaviors as semiconductor-like at high temperature and frequency depending behavior associated with dispersion phenomena at low temperatures. The conduction mechanism in the system is influenced by Cu concentration and the dominant one is the hopping conduction mechanism. Dielectric measurements at the same conditions of temperatures and frequencies exhibited that the dielectric loss increases with increasing the temperature and decreasing the frequency indicating the semiconducting nature of the ferrite compounds. An anomalous behavior of the dielectric loss is observed in samples with high Cu content which explained in terms of resonance between frequency accompanied the electronic hopping and the frequency of the external electric field. The analysis of Mössbauer spectra revealed that copper free compound is super-paramagnetically relaxed in nature and zinc free compound demonstrates ferrimagnetic order. Moreover, hyperfine field spectrum shows the migration of Cu ions from octahedral to tetrahedral site in zinc free compound.

Finite element (FE) model based on kinetic analysis was developed to describe the thermal debinding process of previously solvent debinded metal injection moulded (MIM) copper compacts. Thermophysical properties (specific heat, density, thermal diffusivity and thermal conductivity as a function of temperature) of MIM copper compact were measured using differential scanning calorimeter, laser flash analyser, thermogravimetry analyser and pushrod dilatometer. The proposed model is solved numerically to study binder removal and binder distribution during thermal debinding. The investigations included the analysis of residual (backbone) binder content for cylindrical MIM copper compacts at different temperatures and positions. The FE calculations are strongly based on measured thermophysical data and kinetic analysis of copper system. The FE simulated and experimental results were compared to validate the underlying FE model based on FE temperature field calculations. Drawing the real furnace temperature cond...

Aim: As the labeled anti-camel immunoglobulins (Igs) with enzymes for enzyme-linked immunosorbent assay (ELISA) are unavailable in the Egyptian market, the present investigation was directed for developing local labeled anti-camel IgG with horseradish peroxidase (HRP) to save hard curacy. Materials and Methods: For purification of camel IgG whole molecule, camel sera was preliminary precipitated with 50% saturated ammonium sulfate and dialyzed against 15 mM phosphate-buffered saline pH 7.2 then concentrated. This preparation was further purified by protein A sepharose affinity column chromatography. The purity of the eluted camel IgG was tested by sodium dodecyl sulfate polyacrylamide gel electrophoresi. Anti-camel IgG was prepared by immunization of goats and rabbits separately, with purified camel IgG. The anti-camel IgG was purified by protein A sepharose affinity column chromatography. Whole molecule anti-camel IgG was conjugated with HRP using glutraldehyde based assay. Sensitivity and specificity of prepared conjugated secondary antibodies were detected using positive and negative camel serum samples reacted with different antigens in ELISA, respectively. The potency of prepared conjugated antibodies was evaluated compared with protein A HRP. The stability of the conjugate at −20°C during 1 year was assessed by ELISA. Results: The electrophoretic profile of camel IgG showed four bands of molecular weight 63, 52, 40 and 33 kDa. The recorded sensitivity and specificity of the product are 100%. Its potency is also 100% compared to 58-75% of commercial protein A HRP. The conjugates are stable for 1 year at −20°C as proved by ELISA. Conclusion: Collectively, this study introduces goat and rabbit anti-camel IgG whole molecules with simple, inexpensive method, with 100% sensitivity, 100% specificity and stability up to 1 year at −20°C. The important facet of the current study is saving hard curacy. Future investigations are necessary for preparation of IgG subclasses.

Thermogravimetry (TG) combined with mass spectrometry (MS) has been employed to study the thermal decomposition of the ‘backbone’ binder component of bodies prepared from premixed Fe+12%Cu with 50 vol.-% binder and fabricated by powder injection moulding technique. The investigation of solvent dewaxed Fe+12%Cu parts was made at different heating rates. The TG/MS technique allows evaluating the chemical pathway of the degradation reaction by determining the decomposition products evolving during thermal process. The majority of gaseous products obtained in the experimental set-up used were less than C8. Kinetics analysis was made using chemical reactions proposed through thermokinetics package. The temperature profile was calculated for smooth thermal debinding and was verified by an experimental run in a production furnace. Good agreement showed the reliability of the model.

The outcomes of an experimental study on local scour at a pile cap are presented. Experiments were conducted with the approaching flow having an undisturbed flow depth and a threshold flow velocity. The main variables investigated were pile cap dimensions and location relative to the streambed. According to the rate of change in scour depth, the scour at a pile cap for different cap levels was divided into four cases. Equations for a correction factor for these four cases are derived. The correction factor Kc has the effect of reducing the scour depth from a corresponding full-depth pier of the same width as the pile cap. A new methodology is presented to estimate local scour depth at a pile cap as a component of a complex pier. The proposed method was evaluated with the results from this experimental study and historical measurements. The proposed method, which corresponds closely to the observations, can be used to predict local scour at a pile cap as a component of a complex pier in the superposition method. It is also applicable to the prediction of local scour due to a caisson being sunk onto a mobile bed in a current.

Annihilation characteristics of positrons and positronium (Ps) in thin metal and polymer films were studied. Monoenergetic positrons were implanted into free-standing thin W and Au films and the annihilation γ-rays of positron–electron pairs were measured as a function of the incident energy of positrons. At the front-side surfaces of the films, an emission of Ps into vacuum and a resultant self-annihilation of ortho-Ps ( o -Ps) were observed. At the backside surfaces, the Ps emission was found to be enhanced by an increase in the numbers of epithermal positrons and/or secondary electrons introduced by the impact of energetic positrons. For thin polymer films (polyester and polystyrene), the emission rate of o -Ps from the backside surfaces was higher than that from the metal films, which was attributed to the out-diffusion of o -Ps formed in the films. Those results suggested that the emission rate of Ps into vacuum was sensitive to the Ps formation process in the bulk and at the surface.

Thermal processes involved during the decomposition course of La2(C2O4)3·10H2O–FeC2O4·2H2O (1:2 mole ratio) mixture up to 750 °C, in an atmosphere of air, were monitored by thermogravimetry and differential thermal analysis. X-ray diffraction and Mossbauer spectroscopy were used to characterize the intermediates and the final product. The results showed that a microcrystalline or possibly amorphous iron(III) oxide with a paramagnetic nature was appeared in the early stages of decomposition at 250 °C. By increasing the temperature, a well crystalline hematite with ferromagnetic properties was obtained. XRD pattern of the mixture calcined at 1100 °C shows the formation of LaFeO3 single phase in consistent with the hyperfine magnetic splitting (one sextet of lines) characteristic of LaFeO3 obtained in the Mossbauer spectra of the mixture calcined at the same temperature.

To identify the functioning of the soil-landscape system and its effects on plant growth for native rangeland the relationships between soil properties and landscape function analysis (LFA) indices and between plant growth characteristics and LFA indices were investigated. The results interpreted based on statistical analysis and expert knowledge. This research was carried out for a semi-arid rangeland in the Lar aquifer in Iran. Land stratification allowed the study area to be subdivided into Land Units, according to specified criteria including landform attributes (slope, aspect, and altitude), and vegetation type. A factorial model on the basis of a completely randomized design was used to analyse the data collected from 236 land units. The landscape function indices including nutrient cycling index, infiltration index, stability index, and landscape organization index were derived by various integrations of soil surface attributes. Landscape attributes differed from one another in their effects on the different landscape function indices. Increasing slope gradient significantly reduced all landscape function indices as well as soil organic carbon and total nitrogen percentages. Slope class exhibited highly significant interaction effects with vegetation type factors for stability, nutrient cycling, and landscape organization indices. Aspect did not significantly affect stability, infiltration, and landscape organization indices, but significantly affected the nutrient cycling index. The Duncan test indicated that north aspect (shady side) had the highest mean value (28.42) and south aspect the lowest mean value (25.57) for nutrient cycling index. These results are consistent with the effects of aspect on total soil nitrogen and soil organic carbon percentage for which the north aspect had the highest values. The values declined in the sequence east, west, and south aspects, respectively. This research indicates that the nature of native rangeland plant communities and their measures of production are closely related to nutrient cycling index.

Mixed ferrites with the chemical formula Mg 0.5 Cu 0.5 Ga x Fe 2-x O 4 (0.0 ≤ x ≤ 0.5) were prepared by a ceramic route. X-ray diffraction results confirmed the presence of single-phase spinel structure for these samples. Electrical properties of these ferrites at various compositions were investigated from room temperature up to 550 K in the frequency range 10 2 -10 5 Hz. The obtained results revealed semiconductor behavior at high frequency and metallic behavior at low frequency in these materials. All studied compositions exhibit a transition with a change in the slope of the conductivity versus temperature curve. The obtained transition temperature T C is found to decrease linearly with increasing Ga concentration. As Ga substitutes Fe in these compounds the activation energy for electrical conduction in the ferrimagnetic region (E f ) has a small variation with frequency. In contrast, the activation energy in the paramagnetic region (E p ) shows undefined behavior reflecting the nature of this disordered state. The relation of the universal exponent s with temperature gives evidence for the presence of the large overlap polaron (LOP) hopping conduction mechanism in these compounds. The obtained results are explained in the light of the cation-anion-cation and cation-cation interactions present over the octahedral B-sites in the spinel structure.

Spinel solid solutions of CuFe2O4 and Cu1−x Zn x Ga0.1Fe1.9O4 with (0.0 ≤ x ≤ 0.5) are synthesized. Crystallographic phase transformation from tetragonal-to-cubic occurred at x = 0.2. The derived structural parameters manifest that Zn occupies the tetrahedral A-site while Cu and Ga occupy the octahedral B-site and Fe distributes among A- and B-sites. Electrical conductivity measurements of these materials as a function of temperature and frequency revealed semiconducting behavior except CuFe2O4 sample, which has a metallic behavior at low frequency and at high frequency, semiconductor-to-metallic transition occurred as temperature increases. The metallic behavior in this sample is attributed to cation-cation interactions at B-site while, the semiconductor behavior in Cu1−x Zn x Ga0.1Fe1.9O4 compounds is due to the cation–anion–cation interactions at the same site in the spinel lattice. All compositions exhibit transition with change in the slope of conductivity versus temperature curve. This transition temperature (T c) decreases linearly with increasing Zn content x. The relation of the universal exponent s with temperature gives evidence that over large polaron OLP and correlated barrier hopping CBH conduction mechanisms are presented in CuFe2O4 and Cu1−x Zn x Ga0.1Fe1.9O4 compounds respectively.

Compositions having the chemical formula Cu0.5Co0.5GaxFe2–xO4 with (0.0 ≤ x ≤ 0.5) have been prepared by the usual ceramic processing from high-purity oxides. X-ray diffraction measurements are used for analyzing the composition, lattice parameter, density, porosity and grain size of these compounds. The area ratio of Fe3+ at the tetrahedral A- and octahedral B-sites deduced from the spectral analysis of Mossbauer measurements on the present spinel system gives evidence that Ga replaces Fe at A-site in the range 0.0 0.3), it replaces Fe at B-site. This change in the site preference reflects an abrupt change in the hyperfine parameters with Ga content at x > 0.3. The electrical measurements as a function of temperature and frequency on these materials revealed semiconducting behavior. These results show a significant increase in the frequency dependence of conductivity as Ga content increases. Variation of the universal exponent s with temperature indicates the presence of small-polaron (SP) hopping mechanism at low Ga content. As Ga substitution progressed, the overlap large polaron (OLP) becomes the predominant hopping mechanism in these compounds. The determined transition temperature TC of these samples is found to decrease linearly with increasing Ga content x. The results obtained in this study are interpreted in light of the cation–cation and cation–anion–cation interactions in the spinel structure. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The electrical properties of Cu-substituted Ni–Mn ferrite Ni1–xCuxMnyFe2–yO4 (with 0.0 ≤ x ≤ 1.0 and y = 0.6) are investigated by ac conductivity measurements in the frequency range 102–105 Hz and over the temperature range 300–730 K. The results obtained for these materials reveal a semiconductor-to-metallic transition as Cu content increases. All studied compositions exhibit a transition with a change in the slope of the conductivity versus temperature curve. This transition temperature is found to decrease linearly with increasing Cu concentration. Variations of dielectric permittivities (e′ and e″) and dielectric loss tangent (tan δ) for the studied materials as a function of temperature and frequency are found to be strongly dependent on both Mn and Cu concentrations. The results for conductivity and dielectric parameters (e′ and e″) and tan δ are explained on the basis of cation–anion–cation and cation–cation interactions over the octahedral sites in the spinel structure. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

From 57 Fe Mossbauer measurements carried out on the spinel ferrite under study, the ratio of the integrated intensities of 57 Fe A- and B-site subspectra can be evaluated. The composition of the ferrite has been established as (Fe 3+ )[Ni 2+ Cr 3+ x Fe 3+ 1-x ]O 2- 4 for 0.0 ≤x ≤ 0.6. The composition dependence of the Mossbauer hyperfine parameters (center shift and quadrupole splitting) displays no features in this composition range that would result from a qualitative change in electronic structure. The ac conductivity measurements reveal a semiconducting behavior with a transition in the conductivity versus temperature curve. The transition temperature is found to decrease linearly with increasing Cr concentration x. The dielectric parameters (e'and loss (tan δ)) of the studied samples exhibit dipolar relaxation effects. The results of conductivity and dielectric parameters are explained in the light of hopping conduction at the octahedral B sites.

The dielectric parameters (e', v) and loss (tan δ) are studied in spinel ferrites of NiFe 2 O 4 and Ni 1-x Cu x AlFeO 4 with x from 0.0 to 1.0, as a function of temperature in the frequency range 10 2 to 10 5 Hz. All these samples are found to exhibit dipolar relaxation effects. The variations of e', e and tan δ with frequency and temperature are observed to be strongly dependent on both aluminium and copper concentrations. The results are explained on the basis of the cation-anion-cation and cation-cation interactions over the octahedral sites in the spinel structure.

Two spinel solid solution series, Ni1−xCuxFe2−yAlyO4 with y=0.6 and 1.0, where 0.0⩽x⩽1.0 have been investigated by x-ray diffractometry and Mossbauer spectroscopy. Lattice, hyperfine parameters, and cation distribution among the two distinct crystallographic sites as a function of Cu2+ and Al3+ substitution are determined. Mossbauer effect (ME) spectra at 293 K for compositions with y=0.6 consist of one sextet for A sites, and three sextets for B sites due to different fields at Fe nuclei. On the other hand, the ME spectra for the compounds with y=1.0 in the ferrimagnetic state at (293 and 77 K) show only one sextet for Fe3+ at A site giving clear evidence for a completely inverse spinel with Ni, Cu, and Al ions occupying B sites. ME parameters are deduced and analyzed for all studied compounds, where the observed hyperfine fields are explained on the basis of the superexchange and supertransferred hyperfine interactions.

Death receptors 4 and 5 (DR4 and DR5) are cell surface receptors that when activated by their ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in most cancer cells but not in normal cells. Currently, it remains unclear whether DR4 and DR5 are involved in immune surveillance against nonmelanoma skin cancer (NMSC) progression. The aim of this study was to investigate the expression of DR4 and DR5 in NMSC and relate the results to the established clinicopathologic prognostic factors. This study was conducted on about 80 skin specimens from patients with NMSC (40 basal cell carcinoma and 40 squamous cell carcinoma) and diagnosed and confirmed by biopsy. Immunohistochemical analysis for DR4 and DR5 was carried out on formalin-fixed paraffin-embedded sections of skin tissues using avidin-biotin peroxidase method. Significant expression of both DR4 and DR5 was observed in NMSC cases. There was statistically significant association between DR4 and DR5 expression in squamous cell carcinoma and each of tumor site and lymph node metastasis. There was statistically significant association between DR4 expression in basal cell carcinoma and histopathologic subtypes (high expression in nodular type) and between DR5 expression and tumor site (high expression in sun-exposed area). In conclusion, expression of TRAIL receptors that mediate extrinsic apoptotic pathway in NMSC may be suggestive of a reassessment of the suitability of TRAIL-based strategy in future NMSC therapies.