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1.
Sensors (Basel) ; 24(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38610397

RESUMO

Conventional DC-DC boost converters have played a vital role in electric vehicle (EVs) powertrains by enabling the necessary voltage to increase to meet the needs of electric motors. However, recent developments in high-gain converters have introduced new possibilities with enhanced voltage amplification capabilities and efficiency. This study discusses and evaluates the state-of-the-art high-gain DC-DC converters for EV applications based on the Quadratic Boost Converter (QBC). Research into innovative topologies has increased in response to the increasing demand for efficient and high-performance power electronic converters in the rapidly expanding EV industry. Due to its ability to provide more significant voltage gains than conventional boost converters, the QBC has become a viable option for meeting the unique requirements of EV power systems. This survey focuses on the efficiency, power density, and overall performance parameters of QBC-based high-gain converters. The literature review provides a foundation for comprehending power electronics converters' trends, challenges, and opportunities. The acquired knowledge can enhance the design and optimization of high-gain converters based on the QBC, thereby fostering more sustainable and efficient power systems for the expanding electric mobility industry. In the future, the report suggests that investigating new high-gain converter design methodologies will reduce component stress and enhance the intact system efficiency.

2.
Eur J Clin Microbiol Infect Dis ; 37(12): 2323-2329, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30259214

RESUMO

Almost a decade ago our diagnostic laboratory implemented an in-house real-time PCR for the detection of Plasmodium DNA to diagnose malaria in parallel with conventional diagnostics, i.e., microscopy (thick and thin smears), quantitative buffy coat microscopy (QBC), and a rapid diagnostic test (RDT). Here we report our experiences and make a comparison between the different diagnostic procedures used in this non-endemic setting. All patients during the period February 2009-December 2017 suspected of malaria were prospectively tested at the moment of sample collection. Both PCR and conventional malaria diagnostics were carried out on a total of 839 specimens from 825 patients. In addition, three Plasmodium falciparum (Pf) patients were closely followed by real-time PCR and microscopy after treatment. Overall, 56 samples (55 patients) tested positive by real-time PCR, of which six were missed by microscopy and seven by QBC. RDT showed fairly good results in detecting Pf, whereas specificity was not optimal. RDT failed to detect 10 of 17 non-Pf PCR positive specimens. One Plasmodium malariae patient would have been missed if only conventional diagnostic tests had been used. The high sensitivity of the PCR was confirmed by the number of PCR positive, microscopy negative post-treatment samples. In conclusion, within our routine diagnostic setting, malaria real-time PCR not only showed a high level of agreement with the conventional methods used, but also showed higher sensitivity and better specificity. Still, for complete replacement of the conventional procedures in a non-endemic setting, the time-to-results of the real-time PCR is currently too long.


Assuntos
Malária/diagnóstico , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase em Tempo Real , Antígenos de Protozoários/genética , Humanos , Microscopia , Países Baixos , Plasmodium , Plasmodium falciparum , Estudos Prospectivos , Sensibilidade e Especificidade , Medicina de Viagem
3.
Korean J Parasitol ; 54(4): 393-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27658589

RESUMO

Low parasitemic condition in malaria remains a diagnostic challenge; as the available diagnostic methods failed to detect. Currently, hemozoin (Hz) pigment is gaining attention in the diagnosis of malaria. The major drawback is ease of detection of Hz in routine practice. A pilot study was conducted to evaluate the role of Hz pigment and to compare the performance of quantitative buffy coat assay (QBC) and PCR in such conditions. Clinically suspected cases of malaria were examined by both Giemsa stain and immunochromatographic test (ICT). Samples positive by ICT and negative by Giemsa stain were further examined by nested PCR targeting 18S rRNA and QBC for the presence of malaria parasites and pigments. Thirty blood samples fulfilled the inclusion criteria out of which 23 were Plasmodium vivax (Pv), 4 Plasmodium falciparum (Pf), and 3 mixed (Pv and Pf) by immunochromatographic test. Twenty-one out of 30 (70%) were positive by nested PCR in comparison to 25/30 (83%) by QBC. Samples containing both malaria parasites and Hz pigment by QBC completely showed concordance with the PCR result. However, 61% of total samples containing only Hz pigment were observed positive by PCR. Hz pigment remains an important tool for malaria diagnosis. Identification of leukocytes containing pigments by QBC not only indicates recent malarial infections but also puts light on severity of the disease. QBC assay is a rapid, highly sensitive, and cost-effective method to detect malaria parasites and Hz pigment especially in low parasitemic conditions.


Assuntos
Buffy Coat/química , Buffy Coat/parasitologia , Cromatografia de Afinidade/métodos , Hemeproteínas/análise , Malária/diagnóstico , Reação em Cadeia da Polimerase/métodos , RNA de Protozoário/genética , Humanos , Projetos Piloto , RNA Ribossômico 18S/genética , Sensibilidade e Especificidade
4.
Materials (Basel) ; 15(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36079405

RESUMO

This study presents test results and in-depth discussion regarding the measurement of the fracture mechanics parameters of new concrete composites based on quaternary blended cements (QBC). A composition of the two most commonly used mineral additives, i.e., fly ash (FA) and silica fume (SF), in combination with nanosilica (nS), has been proposed as a partial replacement for ordinary Portland cement (OPC) binder. Four series of concrete were made, one of which was the reference concrete (REF) and the remaining three were QBC. During the research, the main mechanical parameters of compressive strength (fcm) and splitting tensile strength (fctm), as well as fracture mechanics parameters and the critical stress intensity factor KIcS, along with critical crack-tip opening displacements (CTODc) were investigated. Based on the tests, it was found that the total addition of siliceous materials, i.e., SF + nS without FA, increases the strength and fracture parameters of concrete by approximately 40%. On the other hand, supplementing the composition of the binder with SF and nS with 5% of FA additive causes an increase in all mechanical parameters by approximately 10%, whereas an increase by another 10% in the FA content in the concrete mix causes a significant decrease in all the analyzed factors by 10%, compared to the composite with the addition of silica modifiers only.

5.
Int J Lab Hematol ; 43(5): 973-982, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33750012

RESUMO

INTRODUCTION: Point of care testing (POCT) represents a valuable option when laboratory data shall be urgently available for timely clinical management, with a turnaround time (TAT) that is unfeasible using conventional laboratory instrumentation. This study was aimed to compare the performance of QBC STAR™ compared to Sysmex XN-module and the reference optical microscopy (OM) assessment. MATERIAL AND METHODS: One hundred peripheral blood samples, collected in K3 EDTA tubes, and 50 capillary blood samples obtained by finger stick were analyzed with QBC STAR™, Sysmex XN-module, and OM. Data were compared with Passing-Bablok regression and Bland-Altman plots. RESULTS: The Passing-Bablok regression analysis (QBC STAR™ capillary sample vs XN-module) yielded slopes comprised between 0.30 and 1.37, while the intercepts ranged between -17.57 and 232.6. Bland-Altman plots yielded relative bias comprised between -4.87% (for MN QBC STAR™ capillary sample vs XN-module) and 27% (PLT QBC STAR™ capillary sample vs XN-module). A significant bias was found for all parameters except MN and WBC, RBC in all and pediatric samples, and HB in adults samples. CONCLUSION: The results of this analytical evaluation suggest that QBC STAR™ may not be the ideal tool for performing complete blood count analysis for diagnostic purposes, while it could be more useful in urgent/emergent conditions, such as for rapid monitoring of some hematological parameters (eg, WBC and HB).


Assuntos
Contagem de Células Sanguíneas/métodos , Testes Imediatos , Adolescente , Adulto , Contagem de Células Sanguíneas/instrumentação , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Laboratórios , Masculino , Microscopia , Pessoa de Meia-Idade , Dados Preliminares , Análise de Regressão
6.
Artigo em Inglês | MEDLINE | ID: mdl-36776491

RESUMO

The transition from batch to continuous processes in the pharmaceutical industry has been driven by the potential improvement in process controllability, product quality homogeneity, and reduction of material inventory. A quality-by-control (QbC) approach has been implemented in a variety of pharmaceutical product manufacturing modalities to increase product quality through a three-level hierarchical control structure. In the implementation of the QbC approach it is common practice to simplify control algorithms by utilizing linearized models with constant model parameters. Nonlinear model predictive control (NMPC) can effectively deliver control functionality for highly sensitive variations and nonlinear multiple-input-multiple-output (MIMO) systems, which is essential for the highly regulated pharmaceutical manufacturing industry. This work focuses on developing and implementing NMPC in continuous manufacturing of solid dosage forms. To mitigate control degradation caused by plant-model mismatch, careful monitoring and continuous improvement strategies are studied. When moving horizon estimation (MHE) is integrated with NMPC, historical data in the past time window together with real-time data from the sensor network enable state estimation and accurate tracking of the highly sensitive model parameters. The adaptive model used in the NMPC strategy can compensate for process uncertainties, further reducing plant-model mismatch effects. The nonlinear mechanistic model used in both MHE and NMPC can predict the essential but complex powder properties and provide physical interpretation of abnormal events. The adaptive NMPC implementation and its real-time control performance analysis and practical applicability are demonstrated through a series of illustrative examples that highlight the effectiveness of the proposed approach for different scenarios of plant-model mismatch, while also incorporating glidant effects.

7.
Mol Cells ; 43(4): 313-322, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32274918

RESUMO

Eukaryotes transport biomolecules between intracellular organelles and between cells and the environment via vesicle trafficking. Soluble N -ethylmaleimide-sensitive factor attachment protein receptors (SNARE proteins) play pivotal roles in vesicle and membrane trafficking. These proteins are categorized as Qa, Qb, Qc, and R SNAREs and form a complex that induces vesicle fusion for targeting of vesicle cargos. As the core components of the SNARE complex, the SNAP25 Qbc SNAREs perform various functions related to cellular homeostasis. The Arabidopsis thaliana SNAP25 homolog AtSNAP33 interacts with Qa and R SNAREs and plays a key role in cytokinesis and in triggering innate immune responses. However, other Arabidopsis SNAP25 homologs, such as AtSNAP29 and AtSNAP30, are not well studied; this includes their localization, interactions, structures, and functions. Here, we discuss three biological functions of plant SNAP25 orthologs in the context of AtSNAP33 and highlight recent findings on SNAP25 orthologs in various plants. We propose future directions for determining the roles of the less well-characterized AtSNAP29 and AtSNAP30 proteins.


Assuntos
Citocinese/fisiologia , Plantas/química , Proteínas Qc-SNARE/química , Estresse Fisiológico/fisiologia
8.
Clin Microbiol Infect ; 26(1): 115-121, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31158521

RESUMO

OBJECTIVES: Malaria is one of most common tropical diseases encountered in travellers and migrants. It requires an urgent and reliable diagnosis considering its potential severity. In this study, performance of five diagnostic assays were evaluated in a nonendemic region and compared prospectively to quantitative PCR (qPCR). METHODS: A prospective study was conducted at Toulouse Hospital from August 2017 to January 2018 and included all patients with initial Plasmodium screening. Thin and thick blood smears (TnS, TkS), quantitative buffy coat (QBC), rapid diagnostic tests (RDTs) and commercial loop-mediated isothermal amplification (LAMP) were independently performed on each blood sample and compared to our qPCR reference standard. RESULTS: The study encompassed 331 patients, mainly returning from Africa. qPCR detected 73 Plasmodium-positive samples (including 58 falciparum). Individually, LAMP had a 97.3% (71/73) sensitivity, far ahead of TnS (84.9%, 62/73), TkS (86.3%, 63/73), QBC (86.3%, 63/73) and RDT (86.3%, 63/73). RDT demonstrated a high sensitivity for falciparum (98.3%, 57/58) but missed all ovale, malariae and knowlesi infections. Specificity was excellent for all techniques (99.6-100%). The most sensitive diagnosis strategies were TnS + RDT (95.9%, 70/73), TnS + LAMP (97.3%, 71/73) and TnS + RDT + LAMP (100%, 73/73), about 10% higher than strategies using exclusively microscopy, TkS + TnS (87.7%, 64/73) or QBC + TnS (87.7%, 64/73). TnS remains necessary for Plasmodium species identification and quantification. Adding sequentially TnS only on LAMP-positive samples did not decrease TnS + LAMP strategy sensitivity. CONCLUSIONS: In nonendemic countries, the currently recommended microscopy-based strategies seem unsatisfactory for malaria diagnosis considering RDT and LAMP performance, two rapid and sensitive assays that require limited training.


Assuntos
Doenças Transmissíveis Importadas/diagnóstico , Malária/diagnóstico , Microscopia/normas , Técnicas de Diagnóstico Molecular/normas , Técnicas de Amplificação de Ácido Nucleico/normas , África , Doenças Transmissíveis Importadas/parasitologia , França , Humanos , Malária/parasitologia , Microscopia/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Plasmodium , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real/normas , Sensibilidade e Especificidade , Temperatura
9.
Exp Ther Med ; 17(1): 472-478, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30651824

RESUMO

Cholangiocarcinoma (CCA) is the most common type of biliary duct malignancy. Propofol is a fast-acting intravenous anesthetic, which also exerts an anti-cancer effect. The aim of the current study was to explore the effects of propofol on human CCA and the associated mechanisms in vitro. The results indicated that as concentration (0, 1, 5 and 10 µg/ml) of propofol and treatment time (24, 48 and 72 h) increased, the cell inhibition rate of human CCA QBC939 cells increased. Furthermore, treatment with various concentrations of propofol for 48 h resulted in a decrease in migration and invasion capacity in QBC939 cells. Propofol also induced the apoptosis of QBC939 cells and cell cycle arrest in G1 phase. Propofol treatment increased the expression level of Bax and decreased that of Bcl-2. In addition, the effects of propofol on gene expression were evaluated, including Wnt3α, ß-catenin, Snail1 and c-myc in the Wnt/ß-catenin signaling pathway. It was identified that as the concentration of propofol increased, the expression of these genes decreased. In conclusion, the current results indicate that propofol is a promising therapeutic agent for the treatment of CCA.

10.
Oncol Lett ; 10(6): 3545-3550, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26788167

RESUMO

The aim of the present study was to determine whether dihydroartemisinin (DHA) induces apoptosis in the human cholangiocarcinoma QBC939 cell line through the regulation of myeloid cell leukemia-1 (MCL-1) expression. The inhibitory rates of DHA on QBC939 cell proliferation and the effects of DHA on the cell death rates at various DHA concentrations and following various treatment times were examined. The rate of apoptosis and cell cycle changes following DHA treatment were examined and the changes in the expression of MCL-1 mRNAs and MCL-1 proteins following DHA treatment were also examined. The MTT assay and trypan blue staining demonstrated that DHA significantly inhibited the proliferation (P<0.05) and promoted the death of QBC939 cells (P<0.05). The DNA ladder assay and flow cytometry (FCM) analysis demonstrated that the rate of apoptosis in the experimental group was significantly increased following DHA treatment (P<0.01). FCM analysis also demonstrated that DHA treatment led to a reduction in the percentage of QBC939 cells in the G0/G1 and G2/M phases, and the majority of the DNA-treated cells were arrested in the S phase of the cell cycle (P<0.01). Western blot analysis demonstrated that DHA treatment significantly upregulated the expression of the pro-apoptotic MCL-1S protein. In contrast, no significant difference in the expression of the anti-apoptotic MCL-1L protein was observed following DHA treatment. DHA affected the expression of the apoptosis-associated protein MCL-1 through multiple mechanisms. DHA treatment increased the ratio of MCL-1S/MCL-1L protein, thus inducing apoptosis in cholangiocarcinoma cells.

11.
Vet Clin Pathol ; 44(2): 179-87, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25911961

RESUMO

BACKGROUND: Prostaglandin E1 (PGE1) and Iloprost inhibit platelet aggregation and should prevent or minimize preanalytic error with feline platelet enumeration. OBJECTIVES: The objective was to compare the relative effectiveness in reducing errors in platelet enumeration by adding Iloprost to feline EDTA blood specimens in comparison to adding PGE1 or EDTA alone. In addition, a grading system for platelet aggregation in blood smears was evaluated for effectiveness in predicting prominent errors and compared to ADVIA's PLT-CLM flag. Finally, the use of plateletcrit in feline blood with platelet aggregation was evaluated. METHODS: Blood specimens from 35 cats were included. Blood was collected into EDTA tubes with or without Iloprost or PGE1, and was rapidly mixed. Platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), and platelet flags were determined with an ADVIA 2120. Manual PLT was performed with a Leucoplate stain. PLT was determined by an IDEXX VetAutoread hematology analyzer (QBC). RESULTS: Neither addition of Iloprost nor PGE1 to EDTA blood specimens completely prevented platelet aggregation. Iloprost-treated specimens had the least severe aggregation. PGE1 was better than EDTA alone. Significant errors in PLT results were consistently identified by the grading system. ADVIA's PLT-CL flag usually predicted significant errors in PLT. QBC PLT results showed high imprecision. Manual PLT error was smaller than ADVIA PLT in EDTA specimens with aggregation. CONCLUSIONS: Adding Iloprost to feline blood specimens improved platelet enumeration accuracy. A grading system for severity of platelet aggregation and usually the ADVIA's PLT-CL alarm predicted specimens with significant errors in platelet enumeration.


Assuntos
Alprostadil/farmacologia , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Gatos/sangue , Ácido Edético/farmacologia , Iloprosta/farmacologia , Contagem de Plaquetas/veterinária , Animais , Inibidores da Agregação Plaquetária/farmacologia , Contagem de Plaquetas/métodos
12.
ISA Trans ; 58: 222-36, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26117285

RESUMO

The paper attempts to address a new control approach to spacecraft maneuvers based upon the modes of propellant engine. A realization of control strategy is now presented in engine on mode (high thrusts as well as further low thrusts), which is related to small angle maneuvers and engine off mode (specified low thrusts), which is also related to large angle maneuvers. There is currently a coarse-fine tuning in engine on mode. It is shown that the process of handling the angular velocities are finalized via rate feedback system in engine modes, where the angular rotations are controlled through quaternion based control (QBCL)strategy in engine off mode and these ones are also controlled through an optimum PID (OPIDH) strategy in engine on mode.

13.
Photodiagnosis Photodyn Ther ; 10(4): 460-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24284099

RESUMO

BACKGROUND: Nanoparticles have been explored recently as an efficient means to deliver photosensitizers for photodynamic therapy. However, it is largely unknown if polyhematoporphyrin (C34H38N4NaO5, Photosan-II, PS) or other photosensitizers can be efficiently delivered by hollow silica nanoparticles (HSNP). METHODS: Polyhematoporphyrin (C34H38N4NaO5, Photosan-II, PS) was loaded into hollow silica nanoparticles (HSNP) by one-step wet chemical-based synthetic route. Dynamic light scattering (DLS) and polydispersive index (PDI) were used for measurement of the particles size and size distribution. Transmission electron microscope and scanning electron microscopy were used for the microstructure, morphological and chemical composition analysis. Fourier transform infrared spectrometry spectra and fluorescence emission spectrum were obtained. The photobiological activity of the PS-loaded HSNP was evaluated on human cholangiocarcinoma QBC939 cells. The cellular viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptotic and necrotic cells were measured by flow cytometry. RESULTS: DLS measurements showed that the size of the particles is in the range of 25-90 nm. PDI of the PS-loaded HSNP is 0.121 ± 0.01, indicating that samples have excellent quality with narrow size distribution to monomodal systems. In MTT assay, PS-loaded HSNP and free PS of the same concentration killed about 95.3% ± 2.0% and 55.7% ± 1.9% of QBC939 cells, respectively. The flow cytometry demonstrated that the laser induced cell death with PS-loaded HSNP was much more severe than that of free PS (P<0.05). CONCLUSIONS: Photosan-II-loaded hollow silica nanoparticles not only can quickly deliver Photosan-II into cells but also can reach a more high concentration than free Photosan-II. HSNP is a desirable vehicle and the release system that shows promises for photodynamic therapy use, which not only improve the aqueous solubility, stability and transport efficiency of PS, but also increase its photodynamic efficacy compared to free PS.


Assuntos
Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Nanocápsulas/química , Porfirinas/administração & dosagem , Dióxido de Silício/química , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Difusão , Humanos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Porfirinas/química , Resultado do Tratamento
14.
Med J Armed Forces India ; 57(3): 185-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27365599
15.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;31(2): 231-233, mar.-abr. 1998.
Artigo em Português | LILACS | ID: lil-464101

RESUMO

Taking for granted the sensitivity of the Quantitative Buffy Coat (QBC) system, as documented in a murine experimental model, we assayed to detect Trypanosoma cruzi in the peripheral blood of 100 patients with Chagas disease in its chronic phase. By means of the method, no positivity occurred, evently as a consequence of small parasitemias, undetectable by this technique as assessed by the cases in consideration.


Valorizando a sensibilidade do sistema Quantitative Buffy Coat (QBC), documentada em modelo experimental murino, estando os animais com infecção aguda pelo Trypanosoma cruzi houve tentativa de evidenciar esse parasita no sangue periférico de 100 pacientes com doença de Chagas, em fase crônica. Com o emprego desse método, nenhuma positividade ocorreu, evidentemente em virtude das pequenas parasitemias, não reveláveis pela técnica, pelo menos conforme o verificado através da casuística considerada.


Assuntos
Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Chagas/parasitologia , Trypanosoma cruzi/isolamento & purificação , Doença Crônica , Corantes Fluorescentes , Doença de Chagas/sangue , Laranja de Acridina , Trypanosoma cruzi/imunologia
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