Portable through-metal ultrasonic power transfer using a dry-coupled detachable transmitter.

Ultrasonic waves can be used to transfer power and data efficiently through metallic enclosures when feedthroughs are not practical due to structural or electromagnetic shielding considerations. Previous implementations of ultrasonic power transfer (UPT) used a piezoelectric transducer permanently bonded to the metal for efficient ultrasonic coupling. For portable operation, it is essential to have a detachable transmitter (charger) that is only attached to the enclosure while transferring power. This requirement presents several design challenges; notably, detachable ultrasonic coupling typically relies on liquid or gel couplant, which may become inconvenient or less robust during repeated attachment and detachment. Thus, this work develops a dry-coupled detachable UPT system to transfer power efficiently through a metallic enclosure without the need for a liquid couplant. Low attenuation soft elastomers are experimentally tested with a magnetic setup to evaluate their dry-coupled efficiency. Samples with different materials and thicknesses are experimentally tested to select the best configuration for dry ultrasonic coupling. The softest elastomer tested yielded the best ultrasonic efficiency (AC-to-AC) of 68% at 1 MHz. A full DC-to-DC portable (battery-operated) UPT system was then developed and experimentally characterized. The system was capable of delivering up to 3 W of DC power to a resistive load with a total efficiency of 50%.

Elevated serum level of interleukin (IL)-18, interferon (IFN)-gamma and soluble Fas in patients with pulmonary complications in tuberculosis.

Mycobacterium tuberculosis can cause life-threatening complications in which the immune response plays an important role. This study was designed to evaluate the serum levels of interleukin-18 (IL-18), interferon-gamma (IFN-gamma) and soluble Fas (sFas) in cases with pulmonary tuberculosis due to confirmed M. tuberculosis infection. The study comprised 50 patients with M. tuberculosis classified to 13 complicated cases and 37 uncomplicated patients. A significant (P<0.05) increase was found in the serum levels of IL-18, IFN-gamma and sFas in patients compared to controls and also in complicated cases compared to uncomplicated ones. Moreover, a positive significant correlation was found between serum levels of sFas with IL-18 (r=0.532, P<0.001), and with IFN-gamma (r=0.37, P=0.008) and lastly between serum levels of IL-18 with IFN-gamma (r=-0.612, P<0.001). It is concluded from these results with the recent observations that IFN-gamma levels are elevated after successful MTB treatment, suggest the possibility of enhanced Fas expression and then stimulating the infected macrophages to show an increased FasL-induced apoptosis. Modulation of FasL system by M. tuberculosis might represent an escape mechanism to evade the effect of apoptosis. Moreover, the elevated serum levels of IL-18, IFN-gamma and sFas can be considered as pathognomonic markers suggesting pulmonary tuberculosis especially in complicated cases.

Distinct serum immunoglobulins pattern in Egyptian patients with chronic HCV infection analyzed by nephelometry.

Hepatitis C has emerged as a major worldwide public health problem. The host immune response to HCV infection is composed of both a non-specific immune response, including interferon (IFN) production and natural killer (NK) cell activity, and a virus-specific immune response, including humoral and cellular components. Susceptibility to infection has been related to immunological disturbances. Several studies have provided experimental evidence of disorders of both cellular and humoral immunity. The present study was carried out to evaluate the serum immunoglobulins level (IgG, IgM, IgA) and IgG-subclasses (IgG1-4) in chronic hepatitis C patients in comparison with healthy control patients. This study included 50 patients with biochemical, serologic, virologic, and histologic evidence of chronic hepatitis C. Total IgG, IgA, and IgM were assayed by nephelometry. IgG subclasses were assayed using human IgG subclasses enzyme immunoassay. The results showed a significant increase of total serum IgG and IgM levels found in patients with chronic HCV compared with the healthy control patients (P < 0.001 for each). There was a statistically significant difference in the IgG subclasses (IgG1 to IgG4) between the patients and controls (P < 0.001 for each). On the other hand, no significant difference was found between patients and healthy controls in IgA level (P = 0.4). The normal total serum immunoglobulins pattern is apparently shifted in chronic hepatitis C infection in the Egyptian patients. This pattern may include an ethnic or biologic background and could be used in the differentiation of the patients with minimal liver disease.

Localization of leucine aminopeptidase in the Schistosoma mansoni eggs and in liver tissue from infected mice.

Infection with Schistosoma mansoni causes hepatic granuloma formation and fibrosis in response to parasite eggs. The present work localized the leucine aminopeptidase (LAP) in S. mansoni eggs and in liver tissue sections from infected mice. Fresh eggs and livers obtained from infected hamsters were processed and stained with the L-leucine-7-amino-trifluoromethyl-coumarin specific substrate. The L-argnine-7-amino-trifluoro-methylcoumarin and Bestatin (leucine aminopeptidase inhibitor) were used to test the LAP substrate specificity and reactivity. The staining pattern for that enzyme in the egg and liver tissue reflects that the leucine aminopeptidase is a major egg constituent distributed in nearly all the egg except the spine. The control substrates confirmed the substrate broad specificity of LAP. In conclusion, the LAP enzyme is a major egg antigen and the target antigen for the antipathology vaccine development studies.

Interleukin (IL)-4, IL-10, IL-18 and IFN-gamma cytokines pattern in patients with combined hepatitis C virus and Schistosoma mansoni infections.

Schistosoma mansoni infection is characterized by a strong T-helper type 2 (Th2) cell-associated immune response, but in the case of viral infection, it is associated with interferon-gamma (IFN-gamma) increase and induction of Th1 immune response. Few data are available about the immune response of cases infected with combined hepatitis C virus (HCV) and schistosomiasis. Thus, the investigation of the cytokine pattern in patients coinfected with both HCV and Schistosoma mansoni was our rationale. This study included four patient groups: Group 1 included 20 patients infected with chronic HCV, Group 2 included 15 patients infected with schistosomiasis alone, Group 3 included 20 patients with chronic HCV and schistosomiasis and Group 4 included 15 healthy control individuals with matched age and sex. Serum levels of IFN-gamma, interleukin (IL)-4, IL-10 and IL-18 were measured in all groups by enzyme-linked immunosorbent assay. The results showed that the patients infected with HCV had significantly higher serum levels of IFN-gamma and IL-18 compared with the controls and with the patients with schistosomiasis and coinfection (P < 0.001). On the other hand, serum levels of IL-4 and IL-10 were significantly higher in patients with schistosomiasis and coinfection compared with the control group (P < 0.001 and 0.0001, respectively) and with the HCV patients (P < 0.05 and P < 0.001, respectively). A significant increase in serum levels of IL-4 and IL-10 was also found in HCV patients compared with the control (P < 0.05). Schistosomiasis appears to induce a Th2 cytokine profile, with increase in serum levels of IL-4 and IL-10, even in the presence of HCV coinfection. In conclusion, schistosomiasis may downregulate the stimulatory effect of HCV on Th1 cytokines and this may lead to the chronicity of HCV infection in coinfected patients.

Role of concurrent S. mansoni infection in H. pylori-associated gastritis: a flow cytometric DNA-analysis and oxyradicals correlations.

BACKGROUND/AIM: Helicobacter pylori infection is associated with the development of atrophic gastritis and increased gastric epithelial proliferation that is important in developing gastric carcinoma. Some countries with a high prevalence of H. pylori infection have high gastric cancer rates, whereas in others these rates are low. Several theories have been advanced to explain this phenomenon. One of these explanations is that the concurrent parasitic infection that is common in the African population might alter the immune response to H. pylori infection and reduce the incidence of atrophic gastritis. The aim of the present study was to assess whether concurrent Schistosoma mansoni infection with H. pylori has an effect on gastric mucosal injury in view of cell proliferation, apoptosis, pathological changes, nitric oxide (NO), oxyradicals and antioxidant capacity status. PATIENTS/METHODS: Between April 2001 and March 2002, 73 patients were subjected to upper gastrointestinal endoscopy for dyspepsia and liver cirrhosis in the National Liver Institute, Menoufiya University. Biopsies were obtained from any lesion as well as from apparently healthy mucosa. Specimens were preserved in RNA later solution, and then kept at -80 degrees C until utilized for estimation of DNA-flow cytometric assay, reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), NO and lipid peroxidation (LPO) product--malondialdehyde (MDA). Diagnosis of bilharziasis was done by stool analysis, or by sigmoidoscopy and rectal snip. RESULTS: Of the 73 patients, 48 were H. pylori-positive, 34 of them were positive and 14 were negative for S. mansoni. Of the 25 H. pylori-negative cases, 18 were positive and 7 were negative for S. mansoni. Concurrent infection with S. mansoni occurred in 34 patients and they had reduced DNA S-phase (7.57 +/- 4.99 vs. 14.5 +/- 3.11, P = 0.001), reduced proliferation activity (9.95 +/- 3.95 vs. 16.78, P < 0.004) and reduced apoptosis (21.83 +/- 11.64 vs. 26.0 +/- 8.31, P > 0.05) compared with H. pylori infected patients alone. CONCLUSIONS: The results demonstrate that concurrent helminthes infection may modify the inflammatory response to gastric H. pylori infection manifested by the reduction of oxyradical-induced DNA-damage, apoptosis and cellular proliferation activity, and the increase in antioxidant production. Concurrent S. mansoni infection may have a protective effect against the possible progression of H. pylori-induced gastritis towards gastric carcinoma.

Three-dimensional photonic-crystal emission through thermal excitation.

A three-dimensional tungsten photonic crystal is thermally excited and shown to emit light at a narrow band, lambda = 3.3-4.25 microm. The emission is experimentally observed to exceed that of the free-space Planck radiation over a wide temperature range, T = 475-850 K. It is proposed that an enhanced density of state associated with the propagating electromagnetic Bloch waves in the photonic crystal is responsible for this experimental finding.

Highly efficient light emission at lambda = 1.5 microm by a three-dimensional tungsten photonic crystal.

For what is believed to be the first time, a three-dimensional tungsten photonic crystal is demonstrated to emit light effectively at wavelength lambda = 1.5 microm. At a bias of V = 7 V, the thermal emission exhibits a full width at half-maximum of delta lambda = 0.85 microm. Within this narrow band, the emitted optical power is 4.5 W and the electrical-to-optical conversion efficiency is approximately 22% per emitting surface. This unique emission is made possible by a large, absolute bandgap in the infrared lambda and flat photonic dispersion near the band edges and in a narrow absorption band.

All-metallic three-dimensional photonic crystals with a large infrared bandgap.

Three-dimensional (3D) metallic crystals are promising photonic bandgap structures: they can possess a large bandgap, new electromagnetic phenomena can be explored, and high-temperature (above 1,000 degrees C) applications may be possible. However, investigation of their photonic bandgap properties is challenging, especially in the infrared and visible spectrum, as metals are dispersive and absorbing in these regions. Studies of metallic photonic crystals have therefore mainly concentrated on microwave and millimetre wavelengths. Difficulties in fabricating 3D metallic crystals present another challenge, although emerging techniques such as self-assembly may help to resolve these problems. Here we report measurements and simulations of a 3D tungsten crystal that has a large photonic bandgap at infrared wavelengths (from about 8 to 20 microm). A very strong attenuation exists in the bandgap, approximately 30 dB per unit cell at 12 microm. These structures also possess other interesting optical properties; a sharp absorption peak is present at the photonic band edge, and a surprisingly large transmission is observed in the allowed band, below 6 microm. We propose that these 3D metallic photonic crystals can be used to integrate various photonic transport phenomena, allowing applications in thermophotovoltaics and blackbody emission.

Aflatoxin formation and varietal difference of cow pea (Vigna unguiculata (L.) Walp.) and garden pea (Pisum sativum L.) cultivars.

Different cultivars of cow pea and garden pea seeds were surveyed for susceptibility or resistance towards the toxigenic and aflatoxin-producing mould (Aspergillus flavus IMI 102135). The results show that aflatoxin production varied among the different cultivars of both cow pea and garden pea. Morphological and histological characters of the different cultivars tested did not show any relation between colour, shape and size of seeds and the amount of aflatoxin produced. The chemical analysis of the different constituents obtained from both seed coats and seed kernels with susceptible, partially resistant and resistant cow pea and garden pea cultivars revealed that the resistant cultivars of cow pea (namely: Balady cultivar) and garden pea (namely: Melting Sugar cultivar) contained lower levels of sodium and higher levels of phosphate and potassium.

Mycoflora and Fusarium toxins of three types of corn grains in Egypt with special reference to production of trichothecene-toxins.

Sixty three species and 2 varieties which belong to 21 genera of fungi were isolated from corn grains (53 + 2, 36 + 1 and 34 species belonging to 19, 13, and 12 genera from white, yellow and popcorn, respectively). Aspergillus (15 species), Penicillium (17) and Fusarium (4) were the dominant genera isolated from the three types of corn. Of four species of Fusarium, F. moniliforme was the dominant species. F. oxysporum and F. solani were detected in all the three substrates, whereas F. subglutinans was isolated exclusively from yellow corn. A biological assay (brine shrimp larvae) and chemical analysis (TLC, UV spectrophotometery and NMR spectroscopy) of chloroform extracts proved that 7 out of 78 samples were toxic. Diacetoxyscirpenol (4 samples, 98.4-128.4 micrograms/kg corn), T-2 toxin (4 samples, 72.8 to 130.4 micrograms/kg) and zearalenone (7 samples, 22.6 to 80.4 micrograms/kg) were detected, whereas 90% methanol-water re-extracts revealed that 3 out of 78 samples were toxic due to presence of fusarin C (1 sample, 76.8 micrograms/kg) in addition to an unidentified toxic factor (3 samples). Of 22 Fusarium isolates (F. moniliforme, F. oxysporum, F. solani and F. subglutinans; 10,5,5 and 2 isolates, respectively grown on corn grains, the chloroform extracts of 6,3,3 and 1 isolates were toxic to brine shrimp larvae. Based on chemical analysis, diacetoxyscirpenol (10/22 isolates; 9.8 - 78.6 micrograms/g dry corn grains), T-2 toxin (5/22; 20.8 - 60.4 micrograms/g), HT-2 toxin (3/22; 12.4 - 18.6 micrograms/g) and zearalenone (13/22; 9.8 - 38.4 micrograms/g) were identified.(ABSTRACT TRUNCATED AT 250 WORDS)

Natural occurrence of mycotoxins in different spices in Egypt.

A total of 120 different samples belonging to 24 kinds of species collected from different places at Assiut Governorate (Egypt) were examined for the natural occurrence of mycotoxins. TLC analysis of spice extracts revealed the presence of aflatoxins (8-35 micrograms/kg) in 16 samples of anise, black pepper, caraway, black cumin, fennel, peppermint, coriander and marjoram, sterigmatocystin (10-23 micrograms/kg) in ten samples of red pepper, caraway, cumin and marjoram and citrinin (8-12 micrograms/kg) in two samples of black cumin, while ochratoxin A and zearalenone could not be detected.

Mycotoxin producing potential of some isolates of Aspergillus flavus and Eurotium groups from meat products.

All strains (92) of A. flavus group proved to be positive for production of aflatoxin (45 to 1200 micrograms/50 ml medium) on potato dextrose liquid medium, while 59 strains only proved to be positive (35-310 micrograms/50 ml) on 15% NaCl potato-dextrose liquid medium. Most of the strains tested of A. flavus, A. flavus var. columnaris and A. oryzae produced aflatoxins B1, B2, G1 & G2. All positive strains of A. tamarii produced aflatoxins G1 & G2 while the tested isolate of A. zonatus produced aflatoxins B1 & G1. Of 95 strains tested of Eurotium, aflatoxins B1 & G1 were produced by one strain of each of E. chevalieri var. intermedium, E. repens and E. rubrum. Gliotoxin was detected in the extract of two strains of E. chevalieri and one strain of each of E. chevalieri var. intermedium and E. pseudoglaucum on the salt-free medium, and two strains of each of E. chevalieri, E. chevalieri var. intermedium and one of E. pseudoglaucum on 15% NaCl medium. Sterigmatocystin was produced by some strains of E. chevalieri, E. chevalieri var. intermedium, E. amstelodami, E. pseudoglaucum and E. rubrum on the two experimental media. One strain only of E. repens produced ochratoxin A while citrinin was detected in the extract of one strain of E. pseudoglaucum.

Effect of four pesticides on aflatoxin production by Aspergillus flavus IMI 89717.

The effect of three fungicides (Vitavax-Captan, Rizolex-T and Sumisclex) and one insecticide (Actellic), when incorporated into liquid medium or applied to corn grains and sunflower seeds, on the production of aflatoxin by A. flavus IMI 89717 was tested. In liquid medium, aflatoxin production was inhibited by 27%, 82%, 100% and 100% when Vitavax-Captan was added at 10, 25, 50 and 100 ppm, respectively. Sumisclex reduced to some extent the production of total aflatoxin, while Rizolex-T and Actellic did not affect quantitatively the mycotoxin production. Rizolex-T proved to be the most effective pesticides tested on aflatoxin production on both corn-grains and sunflower seeds, while Vitavax-Captan was the second most effective pesticide. Both Sumisclex and Actellic did not inhibit aflatoxin production on either corn grains or sunflower seeds at the levels tested.

Survey of mycoflora and mycotoxins in Egyptian soybean seeds.

After four months in commercial storage, 100 soybean samples from different places of Egyptian Governorates were assayed for filamentous fungal growth at two incubation temperatures (28 and 45 degrees C). 73 species and 8 varieties belonging to 32 genera were isolated by the dilution plate method. At 28 degrees C, the common species were Aspergillus flavus, A. fumigatus, A. niger and A. alutaceus, followed by A. terreus, Penicillium chrysogenum, P. citrinum, Mucor hiemalis, M. racemosus, Emericella nidulans, Rhizopus stolonifer, Nectria haematococca and Scopulariopsis brevicaulis. At 45 degrees C, A. fumigatus was the dominant species followed by Rhizomucor pusillus, Emericella nidulans and Neosartorya fischeri. Penicillium which was one of the most abundant genus at 28 degrees C, absent at 45 degrees C. The seeds were assayed for aflatoxin, ochratoxin A, sterigmatocystin, T-2 and zearalenone by thin layer chromatographic analysis. Aflatoxin was detected in 35% of soybean seed samples (5-35 micrograms/kg). The other mycotoxins were not detected.

Mycotoxin production on different cultivars and lines of broad bean (Vicia faba L.) seeds in Egypt.

One hundred different cultivars and lines of broad bean (Vicia faba L.) seed samples were inoculated with Aspergillus flavus Link (CMI 102135) to determine varietal differences which may support or resist aflatoxin production. Thin-layer chromatographic analysis of the chloroform extracts of the different seed samples revealed that 11 cultivars/lines were highly resistant to seed invasion and aflatoxin production while 9 cultivars/line showed partial resistance. The remaining 80 samples were susceptible to the establishment of A. flavus and aflatoxin accumulation. All the resistant cultivars/lines seed samples were inoculated also with three local isolates of fungi namely; Stachybotrys chartarum (Ehrenb. ex Link) Hughes, Aspergillus ochraceus Wilhelm, and Fusarium oxysporum Schlecht. The resistant seed samples were also resistant for colonization with these fungi and mycotoxin formation.

Survey of the mycoflora and mycotoxins of cotton seeds and cotton seed products in Egypt.

Thirty-nine species and 16 fungal genera were isolated from Egyptian cotton seeds, cotton seed meal and cotton seed cake on 1% glucose-Czapek's agar medium incubated at 28 degrees C. Aspergillus was the most frequent genus and it emerged in 87-100% of the samples contributing 70-98% of total fungi in the three substrates tested. The most common species were A. niger, A. flavus, A. fumigatus, A. terreus and Rhizopus stolonifer; A. niger, A. fumigatus and Penicillium corylophilum; and A. niger, A. flavus, A. terreus, A. nidulans and Rhizopus stolonifer, respectively. Cotton seeds and cotton seed products were naturally contaminated by aflatoxin B1 and B2. About 16% of the different substrates tested were positive for aflatoxin contamination. No citrinin, ochratoxin A, patulin, sterigmatocystin, diacetoxyscirpenol, T-2 toxin or zearalenone were detected in the samples assayed.

Mycoflora and trichothecene toxins of paddy grains from Egypt.

120 species and 38 genera were collected from 64 samples of paddy grains on glucose- and cellulose-Czapek's agar at 28 degrees C. The total count of glycophilic and cellulose-decomposing fungi fluctuated between 216-29760; and 124-11320 colonies/g paddy grains on the two media, respectively. On glucose agar, the most common species were Aspergillus niger, A. flavus, A. sydowi, A. terreus, A. fumigatus, A. ochraceus, Penicillium chrysogenum, P. corylophilum, Fusarium oxysporum, Alternaria alternata, Cladosporium cladosporioides, Trichoderma viride and Mucor racemosus. On cellulose agar with pH 5.5 & 8.0, the most prevalent fungi were Stachybotrys chartarum, S. bisybi, Aspergillus niger, A. flavus, Fusarium oxysporum, Alternaria alternata, Drechslera sativus and Acremonium strictum. Extracts from 64 paddy samples were tested against brine shrimp larvae (Artemis salina). Of these 9 displayed varying degrees of toxicity. Trichothecene-toxins were detected in the extracts of three paddy samples only. Diacetoxyscirpenol and T-2 toxin were detected in two samples and only T-2 toxin in the other.

Screening of zearalenone-producing Fusarium species in Egypt and chemically defined medium for production of the toxin.

296 isolates of Fusarium spp. from 100 samples of ccereal grains were examined for their ability to produce zearalenone on liquid culture medium. Thin layer chromatographic analysis revealed that the mycotoxin was detected from 45 isolates, (F. oxysporum), 36; F. moniliforme, 8; and F. equiseti, one isolate). A suitable liquid medium and some optimal conditions for the biosynthesis of zearalenone were reported. Glutamine and riboflavin stimulated the production of the toxin. The maximum amount of zearalenone appeared at pH 7, after 12 days of incubation at 20 degrees C.

Contribution to the fungal flora of cereal grains in Egypt.

30 genera and 77 species, in addition to 4 varieties were isolated from 25 samples of each of barley, wheat, maize and sorghum grains collected from different places in Egypt. The broadest spectrum of genera and species was recorded in wheat (25 genera and 59 species + 4 varieties) followed by barley (21 genera and 52 species + 2 varieties), sorghum (14 genera and 33 species + 2 varieties) and maize grains (11 genera and 29 species + 2 varieties). Aspergillus, Fusarium, Penicillium, and Rhizopus were the most common genera in the four grains, except maize where Penicillin emerged in low frequency. Aspergillus was the main component of the fungal flora of the four grains and contributed 79-94.4% of the gross total count of fungi. From the preceding genera A. niger, A. flavus, A. fumigatus, F. oxysporum, P. chyrsogenum, P. corylophilum, P. notatum and R. stolonifer were the most frequent.