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41.
Recovery of Staphylococcus aureus in Gray Mugil cephalus Roe (Bottarga): Investigation by an Integrated Cultural/Molecular Approach 下载免费PDF全文
Valeria Brandas Germano Orrù Valentina Carraro Adriana Sanna Giovanni Brajon Fulvio Salati Clara Sanna Maria laura Ciusa Mauro Meloni Valentina Coroneo 《Journal of food science》2015,80(6):M1285-M1290
In the Mediterranean area, salted and dried roe from the gray Mugil cephalus “bottarga” represent a speciality food with great commercial value. Bottarga is currently produced by a traditional handmade process and, the risk of human bacterial contamination during its manufacturing is still unknown; in this perspective the foodborne pathogen Staphylococcus aureus could potentially contaminate this product due to poor sanitation or bad handling during processing. The aim of this work is: to evaluate the contamination level of foodborne pathogens at different product manufacturing stages and, in addition, to describe a fast and realizable method for the rapid detection of S. aureus in bottarga samples in the field. A cultural procedure was initially used to investigate the occurrence of S. aureus and the other main foodborne pathogens in bottarga samples at the different manufacturing stages (from roe to final product). In addition, a molecular approach was used to rapidly determine the presence of total bacteria, S. aureus, and its potential toxigenicity. Of the 194 specimens analyzed, we identified: Clostridium perfringens, Enterococcus spp. and Enterobacteriaceae. However, some samples resulted as being contaminated with S. aureus (4% in roe and 8.7% in the final product). During the bottarga manufacturing process, we observed an increase in pathogen levels (from 102 to 105 CFU/g) in contaminated samples, and entA and entB genotypes were identified. Reconstruction experiments suggest that the fresh roe and the bottarga (not completely dried) could represent a risk for the contamination and growth of pathogen bacteria. 相似文献
42.
Andrea Barbieri Germano Nicollini 《Analog Integrated Circuits and Signal Processing》2014,81(1):229-240
A direct readout circuit configurable for electret or MEMS digital microphones is presented. The circuit includes a transducer buffer, a programmable preamplifier, a ΣΔ modulator, a bandgap reference, a clock detection circuit, and a stability recovery system. The prototype achieves a signal-to-noise-and distortion of 63 dB A-weighted at 1 Pa sound level with a consumption of 470 μA at 1.8 V supply voltage. The active area is 0.72 mm2 in a 0.25 μm CMOS process with MIM capacitor option. 相似文献
43.
Validation of left ventricular volume measurements by gated SPECT 99mTc-labeled sestamibi imaging 总被引:1,自引:0,他引:1
AE Iskandrian G Germano W VanDecker JD Ogilby N Wolf R Mintz DS Berman 《Canadian Metallurgical Quarterly》1998,5(6):574-578
BACKGROUND: Originally, the authors used a combined transcranial-transmalar approach for removal of sphenoorbital tumors. METHODS: More recently, when computed tomography (CT) scanning became available, surgical management of sphenoorbital meningiomas included resection of the hyperostosis in the pterional region, orbital roof and lateral wall, and middle fossa floor. Thereafter, intradural and intraorbital components are removed, as well as infiltrated dura mater. Finally, a periosteal flap is placed over the dural defect and bone reconstructed with methylmethacrylate. RESULTS: Of 25 patients, there was only one death and all but one showed very good to moderate response to treatment. Four recurrences were observed. CONCLUSIONS: Surgical management cannot be uniform in all cases, but must be adapted to each form of presentation. On the basis of the satisfactory results achieved, we feel justified in advising the technique described above with its current modifications. 相似文献
44.
The dependence of minority carrier lifetime on injection level was analyzed to yield recombination center parameters for neutron-irradiated germanium. The results are an improvement over data obtained by other methods because they eliminate a possible dependence of capture probability on temperature, and are more sensitive to energy level position. Six n-type specimens doped with arsenic and antimony in the resistivity range from one to twenty ohm-cm were studied. The results reveal a recombination center level of Er - Ev = 0. 34 ± 0.01 eV for antimony-doped germanium and Er - Ev = 0.335 ± 0.01 eV for arsenic-doped germanium. The dependence of lifetime on injection level for high excitation demonstrated the appropriateness of the model which includes the effect of a level of Ec - Er ~ 0.2 eV. 相似文献
45.
Meningiomas arising in the first two decades of life are uncommon and their characteristics are controversial. Some authors believe meningiomas in younger patients occur in different locations, have more malignant histological features, and have a worse prognosis than those in adults. To address this controversy, the authors retrospectively reviewed 23 cases of meningiomas in patients under 21 years of age at diagnosis who were operated on at the University of Turin (1948 to 1990) or at the University of California, San Francisco (1970 to 1989). These tumors represented 2.9% of all tumors in this age group and 1.8% of all meningiomas during the study period at the two institutions. There were 14 males and nine females. The mean age at surgery was 13.3 +/- 5.6 years; nine cases occurred in the first decade and 14 in the second. The most common neurological symptoms were a focal neurological deficit (33%) and seizures (25%). Seventy percent of the tumors were supratentorial. A gross total resection was performed in 60% of the cases. Histologically, the majority (74%) of the tumors were meningothelial or mixed. An increased number of mitoses was observed in 33% of the tumors, focal necrosis in 29%, and invasion of adjacent brain in 14%; however, none of the tumors was classified as a Grade III (anaplastic) meningioma. All patients are alive without evidence of recurrent disease 3 to 22 years (mean +/- standard deviation: 10 +/- 7.3 years) after surgery. This study confirms the rarity of meningiomas of the first two decades of life and the absence of the female predominance associated with meningiomas in adults. The location and histological features of these tumors are similar to those in adults; they have a low recurrence rate, and the outcome and survival rate are excellent. 相似文献
46.
Nicollini G. Mazoyer Y. Crippa C. Pernici S. Confalonieri P. 《Solid-State Circuits, IEEE Journal of》1993,28(5):605-609
An integrated CMOS antilarson system that requires no external components is presented. Speech time constants as long as 100 ms are digitally realized. A 12-dB antilarsen depth and a 6-dB hysteresis are provided for the specific application where the system is involved, but both of them and the voice time constants can be register programmed to different values. The extra area added to the chip for the antilarsen function is only 0.5 mm2 in a 1.5-μm CMOS technology 相似文献
47.
A CMOS differential line-driver amplifier that uses positive feedback in the input stage to give transconductance multiplication and pole-zero doublet insertion is reported. The gain-bandwidth product at 60 kHz is 30 MHz and the unity-gain frequency is 2.7 MHz. The circuit operates from a single 5-V power supply and can achieve a total harmonic distortion (THD) of -78 dB for a 6-V pp differential output signal at 40 kHz and for a load of 100 Ω and/or 150 pF. For the same measuring condition but with a load of 50 Ω and/or 150 pF, the THD is -73 dB. A power supply rejection of more than 76 dB up to 150 kHz was obtained. The chip occupies an area of 1200 mil2 in a 1.5-μm CMOS technology and dissipates 20 mW 相似文献
48.
This paper describes the design strategy and implementation of a high frequency low voltage pseudo-differential SC filter which use opamps with gain enhancement replica amplifier. Experimental results of a biquad SC bandpass with a center frequency of 10 MHz and a Q of 10 are presented. The realized opamp has an open-loop unity-gain bandwidth of 850 MHz, a phase margin of about 62°, and a dc gain of 50 dB. The prototype filter dissipates 23 mW from a 3 V supply and occupies 0.3 mm 2 in a 0.8 μm N-well single-poly, double-metal CMOS process 相似文献
49.
Bruno Tonsic Araujo José Vitor Bernardes Jr. Edson da Costa Bortoni Germano Lambert-Torres 《电力部件与系统》2017,45(17):1962-1971
This article presents a novel methodology for the determination of synchronous machine parameters from the sudden short-circuit (SCC) test. Records of armature and field currents transient behavior are used to evaluate the d-axis equivalent circuit, including the rotor characteristic reactance, and the traditional synchronous machine parameters. The method is based on the evolutionary computer algorithm, the hybrid particle swarm optimization (HPSO). The developed program has been successfully applied into two large salient pole synchronous machines test data. 相似文献
50.
RS de Brito AI Monteiro LT Aguila RP Timóteo BC Enders RM Germano FV Oliveira 《Canadian Metallurgical Quarterly》1995,48(1):26-32
Superantigens have been used to study peripheral tolerance in CD4+ T cells. The superantigen SEB induces T cell anergy by promoting the differentiation of SEB-activated virgin T cells into anergic memory T cells. Memory T cells from SEB or antigen-primed mice do not proliferate when they are cultured with SEB. The present studies were performed to determine whether memory T cells fail to interact with SEB antigen-presenting cells or whether SEB promotes incomplete or negative signals in memory T cells. When murine virgin and memory T cells were separated on the basis of CD45RB expression and cultured with SEB-pulsed B cells, SEB induced the expression of CD25, which then mediated proliferation when IL-2 was added to the cultures. In addition, SEB promoted the expression of the CD40L, which is required for T helper cell function. Finally, PMA induced a costimulatory signal leading to the proliferation of these cells. Surprisingly, the agents, i.e., IL-2 and PMA, which induced TM cell proliferation in conjunction with SEB failed to induce lymphokine secretion. However, in the presence of IL-4 plus IL-5, the T memory cells induced the SEB-pulsed B cells to secrete IgM and IgG. These results suggest that memory T cells are not simply unresponsive to SEB but are actively anergized. 相似文献