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51.
Non-thermal plasma(NTP) technology offers wide potential use in the food technology, the same as in the unconventional agriculture. Some seeds, dry fruits, grains and their sprouts gain popularity in the culinary industry as ‘raw seeds'. This review paper draws the current research and trends in NTP pre-treatment of selected seeds/fruits that are useable as ‘raw seeds'. The main applications are connected with activation of seed germination, early growth of seedlings,microbial inactivation of seed/fruit surface, and possibility of increasing quantity of biological active compounds in sprouting seeds. The paper presents a list of plant species that are able to be used as ‘raw seed' including current information about main type of NTP treatment implemented. 相似文献
52.
Bozena SEPA ;Vitezslav STRANAK ;Michal SERY ;Milan TICHY ;Petr SPATENKA 《等离子体科学和技术》2008,10(4):506-511
The seeds of Lamb's Quarters (Chenopodium album agg.) were stimulated by low- pressure discharge. The tested seeds were exposed to plasma discharge for different time durations (from 6 minutes to 48 minutes). Germination tests were performed under specified laboratory conditions during seven days in five identical and completely independent experiments. Significant differences between the control and plasma-treated seeds were observed. The treated seeds showed structural changes on the surface of the seat coat. They germinated faster and their sprout accretion on the first day of seed germination was longer. Germination rate for the untreated seeds was 15% while it increased approximately three times (max 55%) for seeds treated by plasma from 12 minutes to 48 minutes. 相似文献
53.
Ivana Fridrichova Lenka Kalinkova Miloslav Karhanek Bozena Smolkova Katarina Machalekova Lenka Wachsmannova Nataliia Nikolaieva Karol Kajo 《International journal of molecular sciences》2021,22(1)
The current guidelines for diagnosis, prognosis, and treatment of endometrial cancer (EC), based on clinicopathological factors, are insufficient for numerous reasons; therefore, we investigated the relevance of miRNA expression profiles for the discrimination of different EC subtypes. Among the miRNAs previously predicted to allow distinguishing of endometrioid ECs (EECs) according to different grades (G) and from serous subtypes (SECs), we verified the utility of miR-497-5p. In ECs, we observed downregulated miR-497-5p levels that were significantly decreased in SECs, clear cell carcinomas (CCCs), and carcinosarcomas (CaSas) compared to EECs, thereby distinguishing EEC from SEC and rare EC subtypes. Significantly reduced miR-497-5p expression was found in high-grade ECs (EEC G3, SEC, CaSa, and CCC) compared to low-grade carcinomas (EEC G1 and mucinous carcinoma) and ECs classified as being in advanced FIGO (International Federation of Gynecology and Obstetrics) stages, that is, with loco-regional and distant spread compared to cancers located only in the uterus. Based on immunohistochemical features, lower miR-497-5p levels were observed in hormone-receptor-negative, p53-positive, and highly Ki-67-expressing ECs. Using a machine learning method, we showed that consideration of miR-497-5p expression, in addition to the traditional clinical and histopathologic parameters, slightly improves the prediction accuracy of EC diagnosis. Our results demonstrate that changes in miR-497-5p expression influence endometrial tumorigenesis and its evaluation may contribute to more precise diagnoses. 相似文献
54.
Tomasz Boczek Marta Sobolczyk Joanna Mackiewicz Malwina Lisek Bozena Ferenc Feng Guo Ludmila Zylinska 《International journal of molecular sciences》2021,22(6)
Calcium in mammalian neurons is essential for developmental processes, neurotransmitter release, apoptosis, and signal transduction. Incorrectly processed Ca2+ signal is well-known to trigger a cascade of events leading to altered response to variety of stimuli and persistent accumulation of pathological changes at the molecular level. To counterbalance potentially detrimental consequences of Ca2+, neurons are equipped with sophisticated mechanisms that function to keep its concentration in a tightly regulated range. Calcium pumps belonging to the P-type family of ATPases: plasma membrane Ca2+-ATPase (PMCA), sarco/endoplasmic Ca2+-ATPase (SERCA) and secretory pathway Ca2+-ATPase (SPCA) are considered efficient line of defense against abnormal Ca2+ rises. However, their role is not limited only to Ca2+ transport, as they present tissue-specific functionality and unique sensitive to the regulation by the main calcium signal decoding protein—calmodulin (CaM). Based on the available literature, in this review we analyze the contribution of these three types of Ca2+-ATPases to neuropathology, with a special emphasis on mental diseases. 相似文献
55.
Characterisation of colloidal and particulate organic carbon in freshwaters by thermal fluorescence quenching 总被引:1,自引:0,他引:1
Three-dimensional excitation-emission matrix (EEM) fluorescence with thermal quenching has been applied to raw and size-fractionated freshwaters. To size-fractionate organic matter, sequential filtration through mixed-ester-cellulose membrane filters with nominal pore size of 1.2, 0.1 and 0.025 microm were used. Humic-like fluorophores (peaks A and C) have been found to dominate EEMs of raw and all size fractions of studied waters. Peak A fluorescence intensity has been found to be more thermally sensitive than peak C fluorescence intensity. Humic-like fluorescence intensity was generally size independent, which indicated that it was present mainly in the smallest size fraction (<0.025 microm). This was confirmed by total organic carbon (TOC) measurements. Peak T (tryptophan-like) fluorescence, that is widely associated with biological activity, exhibited a greater thermal sensitivity of fluorescence intensity in the larger size fractions, demonstrating the presence of more than one fluorophore in different size fractions at this location in optical space. Thermal fluorescence quenching provides insights into organic matter variability and associated colloidal characteristics. 相似文献
56.
Smart wireless sensor systems that incorporate multiple sensors often cannot be implemented on a single chip. Advanced integration
and assembly allows for a more complex conjugation and configuration of multiple system modules implemented under different
technologies together in a small tiny package. In tiny sensor systems such as these, three common challenges seen across most
platforms are: the difficult test access due to non-standard assembly and packaging, the testing of multiple heterogeneous
sensor species, and the strict dimensional requirements limiting availability of any built-in hardware for testing. We discuss
the method of testing by modules for testing a multilayer mechanically flexible wireless multisensor platform. A hierarchical
test flow is presented for verifying the functionalities and assessing the performance of the various modules of the system.
We also present an example of a design for testing feature, a built-in test point access bus that improves reliability for
test point access, reduces the cost of testing and overall system bill-of-material, as well, increases test channel bandwidth
allowing for full access to all critical subsystem nodes. Lastly, we provide examples of subsystem performance assessment
and verification testing of selected sensor species on the multisensor platform as well as the system power consumption versus
transmission range, to illustrate the usefulness of the test concepts, flow, and features introduced. 相似文献
57.
This paper proposes a new approach to designing a BIST Test Vector Generator (TVG) for random vector-resistant circuits based
on reconfigurable Cellular Automata Registers (CARs). Each CAR configuration is constructed by combining rules 90 and 150
and the same approach can also be applied to the Linear Feedback Shift Register (LFSR). The TVG thus designed is able to produce
100% fault coverage with short test time at the cost of low area overhead. To achieve this objective, a new method called
the Rank Order Clustering (ROC) method, is introduced in order to fix a number of inputs at certain values when generating
pseudorandom vectors. It is shown that the ROC method is very simple and efficient in fixing inputs at these values in terms
of complexity. Experimental results have been conducted to demonstrate the applicability of the proposed approach in terms
of hardware size and test application time. 相似文献
58.
Guruprasad Kunchur; Blundell Tom L.; Xie Sancai; Green Jonathan; Szafranska Bozena; Nagel Robert J.; McDowell Karen; Baker C.Ben; Roberts R.Michael 《Protein engineering, design & selection : PEDS》1996,9(10):849-856
The pregnancy-associated glycoproteins (PAGs) are secretoryproducts synthesized by the outer epithelial cell layer (chorion)of the placentas of various ungulate species. The amino acidsequences of eight PAGs have been inferred from cloned cDNAof cattle and sheep, as well as of the non-ruminant pig andhorse. We compare the PAG sequences and present results of thethree-dimensional models of boPAG-1 and ovPAG-1 that were constructedon the basis of the crystal structures of homologous porcinepepsin and bovine chymosin using a rule-based comparative modellingapproach. Further, we compare peptide binding subsites definedby interactions with pepstatin and a decapeptide inhibitor (CH-66)modelled on the basis of crystal structures of other asparticproteinases. We have extended our analysis of the peptide bindingsubsites to the other PAG molecules of known sequence by aligningthe PAG sequences to the structural template derived from thepepsin family and by making use of the three-dimensional modelsof the boPAG-1 and ovPAG-1. The residues that are likely toaffect peptide binding in the boPAG-1, ovPAG-1 and other PAGmolecules have been identified. Sequence comparisons revealthat all PAG molecules may have evolved from a pepsin-like progenitormolecule with the equine PAG most closely related to the pepsins.The presence of substitutions at the S1 and other subsites relativeto pepsin make it unlikely that either bovine, ovine or theporcine PAG-1 have catalytic activity. Only two of the eightPAGs examined (porcine PAG-2 and equine PAG-1) retain featuresof active aspartic proteinases with pepsin-like activity. Ourresults indicate that in the PAGs so far characterized the peptidebinding specificities differ significantly from each other andfrom pepsin, despite their high sequence identities. Analysisof the various peptide binding subsites demonstrates why bothbovine and ovine PAG-1 are capable of binding pepstatin. Thestrong negative charge in the binding cleft of boPAG-1 and ovPAG-1indicates a preference for lysine- or arginine-rich peptides.PAGs represent a family where the possible peptide binding functionmay be retained through their binding specificities, but wherethe catalytic activity may be lost in some cases, such as theboPAG-1, ovPAG-1 and the poPAG-1. 相似文献
59.
A fully differential operational amplifier has been designed and fabricated for a novel high resolution and high frequency analog-to-digital converter(>12-bit). The amplifier mainly consists of folded cascode structure with current source as output loads and common-mode feedback circuits. The technique of feedforward compensation is used in order to improve the settling time and gain bandwidth (GBW) of this amplifier. This amplifier is integrated in 0.8 mm BiCMOS process with an active die area of 0.1 mm2. The DC gain of this amplifier is 90 dB. The GBW and phase margin of this amplifier is 900 MHz and 47°, respectively. The power dissipation is minimized by using BiCMOS technology and is about 25 mW for 2 pF load capacitance. This level of performance is competitive with CMOS and BiCMOS operational amplifier circuits previously reported by nearly two orders of magnitude.Ecole Polytechnique of the University of Montreal 相似文献
60.
Built-in temperature sensors increase the system reliability by predicting eventual faults caused by excessive chip temperatures. In this paper, simple and efficient built-in temperature sensors for the on-line thermal monitoring of microelectronics structures are introduced. The proposed temperature sensors produce a signal oscillating at a frequency proportional to the temperature of the microelectronics structure and therefore they are compatible to the oscillation-test method. The oscillation-test method is a low-cost and robust test method for mixed-signal integrated circuits based on transforming the circuit under test (CUT) to an oscillator. This paper presents the design and detailed characteristics of the sensors proposed based on the CMOS 1.2 µm technology parameters of Mitel S.C.C. Extensive post-layout simulations show that the oscillation frequency is very sensitive to temperature variations. The sensors proposed require very small power dissipation and silicon area. 相似文献