2,638 research outputs found
Ultra Low-Power Analog Median Filters
The design and implementation of three analog median filter topologies, whose transistors operate in the deep weak-inversion region, is described. The first topology is a differential pairs array, in which drain currents are driven into two nodes in a differential fashion, while the second topology is based on a wide range OTA, which is used to maximize the dynamic range. Finally, the third topology uses three range-extended OTAs. The proposed weak-inversion filters were designed and fabricated in ON Semiconductor 0.5 micrometer technology through MOSIS. Experimental results of three-input fabricated prototypes for all three topologies are show, where power consumptions of 90nW in the first case, and 270nW in the other two cases can be noticed. A dual power supply +/-1.5 Volts were used
1.5V fully programmable CMOS Membership Function Generator Circuit with proportional DC-voltage control
A Membership Function Generator Circuit (MFGC) with bias supply of 1.5 Volts and independent DC-voltage programmable functionalities is presented. The realization is based on a programmable differential current mirror and three compact voltage-to-current converters, allowing continuous and quasi-linear adjustment of the center position, height, width and slopes of the triangular/trapezoidal output waveforms. HSPICE simulation results of the proposed circuit using the parameters of a double-poly, three metal layers, 0.5 μm CMOS technology validate the functionality of the proposed architecture, which exhibits a maximum deviation of the linearity in the programmability of 7 %
High Gain Amplifier with Enhanced Cascoded Compensation
A two-stage CMOS operational amplifier with both, gain-boosting and indirect current feedback frequency compensation performed by means of regulated cascode amplifiers, is presented. By using quasi-floating-gate transistors (QFGT) the supply requirements, the number of capacitors and the size of the compensation capacitors respect to other Miller schemes are reduced. A prototype was fabricated using a 0.5 μm technology, resulting, for a load of 45 pF and supply voltage of 1.65 V, in open-loop-gain of 129 dB, 23 MHz of gain-bandwidth product, 60o phase margin, 675 μW power consumption and 1% settling time of 28 ns
Valorization of seaweed carbohydrates: autohydrolysis as a selective and sustainable pretreatment
Seaweeds are promising feedstocks; nevertheless, the lack of systematic approaches to recover different high-value fractions in a clean and sustainable mode hampers their exploitation. Due to this necessity, an innovative environmentally friendly strategy was proposed in this article for the development of a sugar platform from Gelidium sesquipedale: for the first time, autohydrolysis followed by enzymatic saccharification (with cellulolytic and agarolytic cocktails) was applied to agarophyte seaweeds. The wide range of severities (between 2.47 and 4.94) studied in this work proved that the autohydrolysis-based process can be tuned to selectively extract different target carbohydrate fractions. Gelling agents (reaching 30 g/100 g DW) can be obtained by the application of low severity treatments, fermentable sugars or oligosaccharides with the nutraceutical potential (reaching 14 g/100 g DW) are produced when severity is increased, and at the highest severity, platform chemicals (reaching 4 g/100 g DW) are the final product. The reduction of processing times compared to traditional extraction methodologies and the elimination of chemicals used in dilute acid treatments make this strategy a clean and sustainable alternative for the valorization of both glucan and galactan fractions of G. sesquipedale.This work was supported by the Portuguese Foundation forScience and Technology (FCT), under the scope of thestrategic funding of UID/BIO/04469/2020 unit and under thescope of the project “AlgaePlas-Biorefinery of macroalgae forvalorization of the carbohydrate fraction to sustainablebioplastics,”PTDC/BII-BIO/29242/2017.info:eu-repo/semantics/publishedVersio
A single prior course of BCNU-cisplatin chemotherapy has a significant deleterious effect on mobilization kinetics of otherwise untreated patients
Extensive prior treatment with cytotoxic agents is
associated with impaired mobilization of hematopoietic
cells. To assess the effect of a single course of standarddose
chemotherapy (CT), we compared the results of
filgrastim-induced mobilization among two sequential
groups of grade III–IV malignant glioma patients
included in a hematopoietic transplantation program.
The first group (21 patients) had never been treated with
CT until 2 days after surgery, when they received a course
of 100 mg/m2 BCNU (IV) and 100 mg intracarotid
cisplatin for cytoreduction (not for mobilization). At 1
month after this CT, they were mobilized with 12 lg/kg
filgrastim. The second group (22 patients) was mobilized
with the same dose of filgrastim directly after the surgery,
without having ever received any prior CT. The blood level
of CD34þ cells was significantly lower in the CT-treated
patients, both on the fourth day of filgrastim (15 vs 36
cells 106/l; P¼0.01) and on the fifth (25 vs
58 cells 106/l; P¼0.003), as it was the number of
CD34þ cells collected per apheresis (1.3 vs 3.5 106/l;
Po0.0005). The toxic effect of a single course of BCNUcisplatin
CT led to significant impairment of the
filgrastim-induced mobilization response.
Bone Marrow Transplantation advance onlin
Operacionalização de uma planta de pirólise rápida de biomassa com reator de leito fluidizado.
Neste trabalho são discutidos os principais problemas encontrados durante a operação da planta piloto de pirólise rápida de biomassa, pertencente à Universidade Estadual de Campinas- Unicamp, Brasil. Essa planta foi ajustada para a produção de bio-óleo, a partir de resíduos de biomassa de pequeno tamanho. Durante os testes, os principais problemas identificados foram: escoamento de vapores da pirólise pelo sistema de alimentação de biomassa; travamento da rosca de alimentação de biomassa; segregação da biomassa no leito; sinterização do material inerte; acúmulo de biomassa e de carvão vegetal dentro do reator; dificuldade para o aquecimento do inerte e baixa eficiência de recuperação de bio-óleo. Os resultados dos testes exploratórios permitiram definir condições operacionais para possibilitar o trabalho estável do reator, aumentar o conhecimento sobre os fenômenos que ocorrem durante a pirólise rápida em leito fluidizado, além do estabelecimento de faixas operacionais para vários fatores independentes, visando a futuros trabalhos de otimização experimental
Acquired potential N-glycosylation sites within the tumor-specific immunoglobulin heavy chains of B-cell malignancies
Background and Objectives. Among B-cell malignancies, follicular lymphomas (FL)
more frequently show acquired, potential N-glycosylation sites (AGS) within tumor-specific
immunoglobulin. The aim of this study was to extend this observation and to evaluate
the pattern of presentation of AGS within five different forms of B-cell lymphoma.
Design and Methods. We sequenced the tumor-specific immunoglobulin heavy chain
variable region fragment, including complementarity-determining regions 2 and 3, of
forty-seven consecutive patients with a B-cell malignancy enrolled in idiotype vaccine
clinical trials. This sequencing approach is known to allow the identification of most AGS.
We then statistically analyzed differences in presentation pattern, in terms of tumor histology,
immunoglobulin isotype, AGS location and amino acid composition.
Results. All twenty-four FL cases presented with at least one AGS, whereas the vast
majority of four B-cell lymphoma types other than FL did not. The non- FL group of tumors
included four cases of Burkitt’s lymphoma, six of diffuse large cell lymphoma, seven mantle
cell lymphomas and six small lymphocytic lymphomas. Most IgM-bearing follicular
lymphoma cases featured their AGS within complementarity-determining region 2, as
opposed to those bearing an IgG, which mostly displayed the AGS within complementarity-
determining region 3. The vast majority of AGS located within either complementarity-
determining region ended with a serine residue, whereas those located within framework
regions mostly featured threonine as the last amino acid residue.
Interpretation and Conclusions. In our series, all cases of FL had AGS within their
tumor-specific immunoglobulin heavy chain variable regions. In contrast, most B-cell
malignancies other than FL did not. Further studies are warranted in order to establish
the possible meaning of these findings in terms of disease pathogenesis, their diagnostic
value in doubtful cases and their potential implications for immunotherapy
Target Selection for the Apache Point Observatory Galactic Evolution Experiment (APOGEE)
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a
high-resolution infrared spectroscopic survey spanning all Galactic
environments (i.e., bulge, disk, and halo), with the principal goal of
constraining dynamical and chemical evolution models of the Milky Way. APOGEE
takes advantage of the reduced effects of extinction at infrared wavelengths to
observe the inner Galaxy and bulge at an unprecedented level of detail. The
survey's broad spatial and wavelength coverage enables users of APOGEE data to
address numerous Galactic structure and stellar populations issues. In this
paper we describe the APOGEE targeting scheme and document its various target
classes to provide the necessary background and reference information to
analyze samples of APOGEE data with awareness of the imposed selection criteria
and resulting sample properties. APOGEE's primary sample consists of ~100,000
red giant stars, selected to minimize observational biases in age and
metallicity. We present the methodology and considerations that drive the
selection of this sample and evaluate the accuracy, efficiency, and caveats of
the selection and sampling algorithms. We also describe additional target
classes that contribute to the APOGEE sample, including numerous ancillary
science programs, and we outline the targeting data that will be included in
the public data releases.Comment: Accepted to AJ. 31 pages, 11 figure
A CMOS Morlet Wavelet Generator
The design and characterization of a CMOS circuit for Morlet wavelet generation is introduced. With the proposed Morlet wavelet circuit, it is possible to reach a~low power consumption, improve standard deviation (σ) control and also have a small form factor. A prototype in a double poly, three metal layers, 0.5 µm CMOS process from MOSIS foundry was carried out in order to verify the functionality of the proposal. However, the design methodology can be extended to different CMOS processes. According to the performance exhibited by the circuit, may be useful in many different signal processing tasks such as nonlinear time-variant systems
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