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1.
Sensors (Basel) ; 22(8)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35458893

RESUMO

The Radiation and Dust Sensor is one of six sensors of the Mars Environmental Dynamics Analyzer onboard the Perseverance rover from the Mars 2020 NASA mission. Its primary goal is to characterize the airbone dust in the Mars atmosphere, inferring its concentration, shape and optical properties. Thanks to its geometry, the sensor will be capable of studying dust-lifting processes with a high temporal resolution and high spatial coverage. Thanks to its multiwavelength design, it will characterize the solar spectrum from Mars' surface. The present work describes the sensor design from the scientific and technical requirements, the qualification processes to demonstrate its endurance on Mars' surface, the calibration activities to demonstrate its performance, and its validation campaign in a representative Mars analog. As a result of this process, we obtained a very compact sensor, fully digital, with a mass below 1 kg and exceptional power consumption and data budget features.


Assuntos
Poeira , Meio Ambiente Extraterreno , Atmosfera
2.
J Environ Sci (China) ; 51: 13-20, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28115123

RESUMO

The pharmaceutical compound indomethacin is not totally removed in wastewater treatment plants, whose effluents flow into aquatic environments; concentrations in the 0.1-100ng/L range are commonly found in surface waters, and its fate is unknown. Here, biological, photochemical and thermal degradation assays were conducted under stress and non-stress conditions to estimate its degradation rate in river water and establish its degradation products over time. The results revealed that direct sunlight irradiation promoted the complete degradation of indomethacin (2µg/L) in less than 6hr, but indomethacin was detected over a period of 4months when water was kept under the natural day-night cycle and the exposure to sunlight was partially limited, as occurs inside a body of water. The biological degradation in water was negligible, while the hydrolysis at pH7.8 was slow. Residues were monitored by ultra-pressure liquid chromatography/quadrupole time-of-flight/mass spectrometry after solid-phase extraction, and six degradation products were found; their structures were proposed based on the molecular formulae and fragmentation observed in high-resolution tandem mass spectra. 4-Chlorobenzoic and 2-acetamido-5-methoxybenzoic acids were the long-term transformation products, persisting for at least 30weeks in water kept under non-stress conditions. Furthermore, the degradation in the presence of sediment was also monitored over time, with some differences being noted. The adsorption coefficients of indomethacin and degradation products on river sediment were calculated; long-term degradation products did not have significant adsorption to sediment.


Assuntos
Anti-Inflamatórios não Esteroides/química , Sedimentos Geológicos/química , Indometacina/química , Poluentes Químicos da Água/química , Absorção Fisico-Química , Anti-Inflamatórios não Esteroides/análise , Monitoramento Ambiental , Modelos Químicos , Rios/química
3.
BMC Microbiol ; 16(1): 228, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27688001

RESUMO

BACKGROUND: Lactic acid bacteria (LAB) are part of the gut microbiota and produce ribosomally synthesized antimicrobial peptides or bacteriocins with interest as natural food preservatives and therapeutic agents. Bacteriocin-producing LAB are also attractive as probiotics. Griffon vultures (Gyps fulvus subspecies fulvus) are scavenger birds that feed almost exclusively on carrion without suffering apparent ill effects. Therefore, griffon vultures might be considered a reservoir of bacteriocin-producing lactic acid bacteria (LAB) with potential biotechnological applications. RESULTS: Griffon vulture feces were screened for LAB with antimicrobial activity, genes encoding bacteriocins, potential virulence determinants, susceptibility to antibiotics, genotyping and characterization of bacteriocins. In this study, from 924 LAB evaluated 332 isolates (36 %) showed direct antimicrobial activity against Gram-positive bacteria only. The molecular identification of the most antagonistic 95 isolates showed that enterococci was the largest LAB group with antimicrobial activity (91 %) and E. faecium (40 %) the most identified antagonistic species. The evaluation of the presence of bacteriocin structural genes in 28 LAB isolates with the highest bacteriocinogenic activity in their supernatants determined that most enterococcal isolates (75 %) encoded multiple bacteriocins, being enterocin A (EntA) the largest identified (46 %) bacteriocin. Most enterococci (88 %) were resistant to multiple antibiotics. ERIC-PCR and MLST techniques permitted genotyping and recognition of the potential safety of the bacteriocinogenic enterococci. A multiple-step chromatographic procedure, determination of the N-terminal amino acid sequence of purified bacteriocins by Edman degradation and a MALDI TOF/TOF tandem MS procedure permitted characterization of bacteriocins present in supernatants of producer cells. CONCLUSIONS: Enterococci was the largest LAB group with bacteriocinogenic activity isolated from griffon vulture feces. Among the isolates, E. faecium M3K31 has been identified as producer of enterocin HF (EntHF), a bacteriocin with remarkable antimicrobial activity against most evaluated Listeria spp. and of elevated interest as a natural food preservative. E. faecium M3K31 would be also considered a safe probiotic strain for use in animal nutrition.

4.
Microb Cell Fact ; 14: 166, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26471395

RESUMO

BACKGROUND: Bacteriocins produced by lactic acid bacteria (LAB) attract considerable interest as natural and nontoxic food preservatives and as therapeutics whereas the bacteriocin-producing LAB are considered potential probiotics for food, human and veterinary applications, and in the animal production field. Within LAB the lactobacilli are increasingly used as starter cultures for food preservation and as probiotics. The lactobacilli are also natural inhabitants of the gastrointestinal (GI) tract and attractive vectors for delivery of therapeutic peptides and proteins, and for production of bioactive peptides. Research efforts for production of bacteriocins in heterologous hosts should be performed if the use of bacteriocins and the LAB bacteriocin-producers is ever to meet the high expectations deposited in these antimicrobial peptides. The recombinant production and functional expression of bacteriocins by lactobacilli would have an additive effect on their probiotic functionality. RESULTS: The heterologous production of the bacteriocin enterocin A (EntA) was evaluated in different Lactobacillus spp. after fusion of the versatile Sec-dependent signal peptide (SP usp45 ) to mature EntA plus the EntA immunity gene (entA + entiA) (fragment UAI), and their cloning into plasmid vectors that permitted their inducible (pSIP409 and pSIP411) or constitutive (pMG36c) production. The amount, antimicrobial activity (AA) and specific antimicrobial activity (SAA) of the EntA produced by Lactobacillus sakei Lb790, Lb. plantarum NC8 and Lb. casei CECT475 transformed with the recombinant plasmids pSIP409UAI, pSIP411UAI and pMGUAI varied depending of the expression vector and the host strain. The Lb. casei CECT475 recombinant strains produced the largest amounts of EntA, with the highest AA and SAA. Supernatants from Lb. casei CECT (pSIP411UAI) showed a 4.9-fold higher production of EntA with a 22.8-fold higher AA and 4.7-fold higher SAA than those from Enterococcus faecium T136, the natural producer of EntA. Moreover, supernatants from Lb. casei CECT475 (pSIP411UAI) showed a 15.7- to 59.2-fold higher AA against Listeria spp. than those from E. faecium T136. CONCLUSION: Lb. casei CECT457 (pSIP411UAI) may be considered a promising recombinant host and cell factory for the production and functional expression of the antilisterial bacteriocin EntA.


Assuntos
Bacteriocinas/metabolismo , Lactobacillus/metabolismo , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bacteriocinas/genética , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Listeria/efeitos dos fármacos , Plasmídeos/genética , Plasmídeos/metabolismo , Sinais Direcionadores de Proteínas/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
5.
Am J Pathol ; 183(4): 1156-1168, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23954273

RESUMO

Semaphorin-3A (Sema3a), a guidance protein secreted by podocytes, is essential for normal kidney patterning and glomerular filtration barrier development. Here, we report that podocyte-specific Sema3a gain-of-function in adult mice leads to proteinuric glomerular disease involving the three layers of the glomerular filtration barrier. Reversibility of the glomerular phenotype upon removal of the transgene induction provided proof-of-principle of the cause-and-effect relationship between podocyte Sema3a excess and glomerular disease. Mechanistically, excess Sema3a induces dysregulation of nephrin, matrix metalloproteinase 9, and αvß3 integrin in vivo. Sema3a cell-autonomously disrupts podocyte shape. We identified a novel direct interaction between the Sema3a signaling receptor plexinA1 and nephrin, linking extracellular Sema3a signals to the slit-diaphragm signaling complex. We conclude that Sema3a functions as an extracellular negative regulator of the structure and function of the glomerular filtration barrier in the adult kidney. Our findings demonstrate a crosstalk between Sema3a and nephrin signaling pathways that is functionally relevant both in vivo and in vitro.


Assuntos
Nefropatias/patologia , Glomérulos Renais/patologia , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Receptores de Superfície Celular/metabolismo , Semaforina-3A/metabolismo , Animais , Forma Celular , Regulação para Baixo , Membrana Basal Glomerular/metabolismo , Membrana Basal Glomerular/patologia , Membrana Basal Glomerular/ultraestrutura , Integrina alfaVbeta3/metabolismo , Nefropatias/metabolismo , Glomérulos Renais/metabolismo , Glomérulos Renais/ultraestrutura , Camundongos , Podócitos/ultraestrutura , Ligação Proteica , Proteinúria/metabolismo , Proteinúria/patologia , Transdução de Sinais
6.
BMC Ecol ; 14: 26, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25476419

RESUMO

BACKGROUND: Studying the drivers and determinants of species, population and community spatial patterns is central to ecology. The observed structure of community assemblages is the result of deterministic abiotic (environmental constraints) and biotic factors (positive and negative species interactions), as well as stochastic colonization events (historical contingency). We analyzed the role of multi-scale spatial component of soil environmental variability in structuring earthworm assemblages in a gallery forest from the Colombian "Llanos". We aimed to disentangle the spatial scales at which species assemblages are structured and determine whether these scales matched those expressed by soil environmental variables. We also tested the hypothesis of the "single tree effect" by exploring the spatial relationships between root-related variables and soil nutrient and physical variables in structuring earthworm assemblages. Multivariate ordination techniques and spatially explicit tools were used, namely cross-correlograms, Principal Coordinates of Neighbor Matrices (PCNM) and variation partitioning analyses. RESULTS: The relationship between the spatial organization of earthworm assemblages and soil environmental parameters revealed explicitly multi-scale responses. The soil environmental variables that explained nested population structures across the multi-spatial scale gradient differed for earthworms and assemblages at the very-fine- (<10 m) to medium-scale (10-20 m). The root traits were correlated with areas of high soil nutrient contents at a depth of 0-5 cm. Information on the scales of PCNM variables was obtained using variogram modeling. Based on the size of the plot, the PCNM variables were arbitrarily allocated to medium (>30 m), fine (10-20 m) and very fine scales (<10 m). Variation partitioning analysis revealed that the soil environmental variability explained from less than 1% to as much as 48% of the observed earthworm spatial variation. CONCLUSIONS: A large proportion of the spatial variation did not depend on the soil environmental variability for certain species. This finding could indicate the influence of contagious biotic interactions, stochastic factors, or unmeasured relevant soil environmental variables.


Assuntos
Florestas , Oligoquetos/fisiologia , Solo , Animais , Biota , Colômbia , Raízes de Plantas/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Clima Tropical
7.
Healthcare (Basel) ; 12(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338223

RESUMO

Stroke is the third leading cause of disability in the world, and effective rehabilitation is needed to improve lost functionality post-stroke. In this regard, robot-assisted therapy (RAT) and transcranial direct current stimulation (tDCS) are promising rehabilitative approaches that have been shown to be effective in motor recovery. In the past decade, they have been combined to study whether their combination produces adjuvant and greater effects on stroke recovery. The aim of this study was to estimate the effectiveness of the combined use of RATs and tDCS in the motor recovery of the upper extremities after stroke. After reviewing 227 studies, we included nine randomised clinical trials (RCTs) in this study. We analysed the methodological quality of all nine RCTs in the meta-analysis. The analysed outcomes were deficit severity, hand dexterity, spasticity, and activity. The addition of tDCS to RAT produced a negligible additional benefit on the effects of upper limb function (SMD -0.09, 95% CI -0.31 to 0.12), hand dexterity (SMD 0.12, 95% CI -0.22 to 0.46), spasticity (SMD 0.04, 95% CI -0.24 to 0.32), and activity (SMD 0.66, 95% CI -1.82 to 3.14). There is no evidence of an additional effect when adding tDCS to RAT for upper limb recovery after stroke. Combining tDCS with RAT does not improve upper limb motor function, spasticity, and/or hand dexterity. Future research should focus on the use of RAT protocols in which the patient is given an active role, focusing on the intensity and dosage, and determining how certain variables influence the success of RAT.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38363693

RESUMO

OBJECTIVE: This study aimed to assess the impact of combining transcranial direct current stimulation (tDCS) with end-effector robot-assisted treatment (RAT) on upper limb function, spasticity, and hand dexterity in chronic stroke patients. DESIGN: This was a prospective, double-blind randomized trial with 20 equally allocated stroke patients. The experimental group received dual-tDCS (anode over affected M1, cathode over contralateral M1) alongside RAT, while the control group received sham tDCS with the same electrode placement + RAT. Each patient underwent 20 combined tDCS and RAT sessions. The primary outcome measure was the Fugl Meyer Upper Limb motor score (mFM-UL), with secondary outcomes including AMADEO® kinematic measures, Action Research Arm Test (ARAT), and Functional Independence Measure (FIM). Assessments were conducted at baseline, post-rehabilitation, and three months later. RESULTS: Combining bilateral tDCS with RAT did not yield additional improvements in mFM-UL, FIM, or ARAT scores among stroke patients. However, the real tDCS group showed enhanced finger flexion in the affected hand based on AMADEO® kinematic measures. CONCLUSION: The addition of tDCS to RAT did not result in significant overall functional improvements in chronic stroke patients. However, a benefit was observed in finger flexion of the affected hand.

9.
J Ind Microbiol Biotechnol ; 40(9): 977-93, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23794087

RESUMO

Mature sakacin A (SakA, encoded by sapA) and its cognate immunity protein (SakI, encoded by sapiA), and two SakA-derived chimeras mimicking the N-terminal end of mature enterocin P (EntP/SakA) and mature enterocin A (EntA/SakA) together with SakI, were fused to different signal peptides (SP) and cloned into the protein expression vectors pNZ8048 and pMG36c for evaluation of their production and functional expression by different lactic acid bacteria. The amount, antimicrobial activity, and specific antimicrobial activity of SakA and its chimeras produced by Lactococcus lactis subsp. cremoris NZ9000 depended on the SP and the expression vector. Only L. lactis NZ9000 (pNUPS), producing EntP/SakA, showed higher bacteriocin production and antimicrobial activity than the natural SakA-producer Lactobacillus sakei Lb706. The lower antimicrobial activity of the SakA-producer L. lactis NZ9000 (pNUS) and that of the EntA/SakA-producer L. lactis NZ9000 (pNUAS) could be ascribed to secretion of truncated bacteriocins. On the other hand, of the Lb. sakei Lb706 cultures transformed with the pMG36c-derived vectors only Lb. sakei Lb706 (pGUS) overproducing SakA showed a higher antimicrobial activity than Lb. sakei Lb706. Finally, cloning of SakA and EntP/SakA into pPICZαA and pKLAC2 permitted the production of SakA and EntP/SakA by recombinant Pichia pastoris X-33 and Kluyveromyces lactis GG799 derivatives although their antimicrobial activity was lower than expected from their production.


Assuntos
Bacteriocinas/biossíntese , Bacteriocinas/farmacologia , Clonagem Molecular , Kluyveromyces/genética , Lactobacillus/genética , Pichia/genética , Proteínas Recombinantes de Fusão/biossíntese , Bacteriocinas/química , Bacteriocinas/genética , Kluyveromyces/metabolismo , Ácido Láctico/metabolismo , Lactobacillus/metabolismo , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Pichia/metabolismo , Sinais Direcionadores de Proteínas/genética , Sinais Direcionadores de Proteínas/fisiologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Análise de Sequência de Proteína
10.
ACS Appl Mater Interfaces ; 15(6): 8624-8635, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36724387

RESUMO

Incorporating an intentional strain compensating InSb interface (IF) layer in InAs/GaSb type-II superlattices (T2SLs) enhances device performance. But there is a lack of studies that correlate this approach's optical and structural quality, so the mechanisms by which this improvement is achieved remain unclear. One critical issue in increasing the performance of InAs/GaSb T2SLs arises from the lattice mismatch between InAs and GaSb, leading to interfacial strain in the structure. Not only that but also, since each side of the InAs/GaSb heterosystem does not have common atoms, there is a possibility of atomic intermixing at the IFs. To address such issues, an intentional InSb interfacial layer is commonly introduced at the InAs-on-GaSb and GaSb-on-InAs IFs to compensate for the strain and the chemical mismatches. In this report, we investigate InAs/GaSb T2SLs with (Sample A) and without (Sample B) InSb IF layers emitting in the mid-wavelength infrared (MWIR) through photoluminescence (PL) and band structure simulations. The PL studies indicate that the maximum PL intensity of Sample A is 1.6 times stronger than that of Sample B. This could be attributed to the effect of migration-enhanced epitaxy (MEE) growth mode. Band structure simulations understand the impact of atomic intermixing and segregation at T2SL IFs on the bandgap energy and PL intensity. It is observed that atomic intermixing at the IFs changes the bandgap energy and significantly affects the wave function overlap and the optical property of the samples. Transmission electron microscopy (TEM) measurements reveal that the T2SL IFs in Sample A are very rough compared to sharp IFs in Sample B, indicating a high possibility of atomic intermixing and segregation. Based on these results, it is believed that high-quality heterostructure could be achieved by controlling the IFs to enhance its structural and compositional homogeneities and the optical properties of the T2SLs.

11.
Chem Mater ; 35(11): 4435-4448, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37332680

RESUMO

This work reports on an alternative and advantageous procedure to attain VO2-based thermochromic coatings on silicon substrates. It involves the sputtering of vanadium thin films at glancing angles and their subsequent fast annealing in an air atmosphere. By adjusting thickness and porosity of films as well as the thermal treatment parameters, high VO2(M) yields were achieved for 100, 200, and 300 nm thick layers treated at 475 and 550 °C for reaction times below 120 s. Comprehensive structural and compositional characterization by Raman spectroscopy, X-ray diffraction, and scanning-transmission electron microscopies combined with analytical techniques such as electron energy-loss spectroscopy bring to the fore the successful synthesis of VO2(M) + V2O3/V6O13/V2O5 mixtures. Likewise, a 200 nm thick coating consisting exclusively of VO2(M) is also achieved. Conversely, the functional characterization of these samples is addressed by variable temperature spectral reflectance and resistivity measurements. The best results are obtained for the VO2/Si sample with changes in reflectance of 30-65% in the near-infrared at temperatures between 25 and 110 °C. Similarly, it is also proven that the achieved mixtures of vanadium oxides can be advantageous for certain optical applications in specific infrared windows. Finally, the features of the different structural, optical, and electrical hysteresis loops associated with the metal-insulator transition of the VO2/Si sample are disclosed and compared. These remarkable thermochromic performances hereby accomplished highlight the suitability of these VO2-based coatings for applications in a wide range of optical, optoelectronic, and/or electronic smart devices.

12.
Appl Environ Microbiol ; 78(16): 5956-61, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22685156

RESUMO

The bacteriocin enterocin A (EntA) produced by Enterococcus faecium T136 has been successfully cloned and produced by the yeasts Pichia pastoris X-33EA, Kluyveromyces lactis GG799EA, Hansenula polymorpha KL8-1EA, and Arxula adeninivorans G1212EA. Moreover, P. pastoris X-33EA and K. lactis GG799EA produced EntA in larger amounts and with higher antimicrobial and specific antimicrobial activities than the EntA produced by E. faecium T136.


Assuntos
Bacteriocinas/biossíntese , Bacteriocinas/genética , Clonagem Molecular , Enterococcus faecium/genética , Leveduras/genética , Leveduras/metabolismo , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Enterococcus faecium/metabolismo
13.
Chemosphere ; 287(Pt 1): 132076, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34478963

RESUMO

Concentration data of veterinary drugs in microalgae biomass collected from photobioreactors fed with piggery wastewaters are presented for the first time in this work. To this aim, a QuEChERS methodology and an ultrasound-assisted solid-liquid extraction have been assessed as sample preparation procedures with the purpose of determining 20 veterinary drugs, mainly antibiotics of different physico-chemical properties in addition to dexamethasone, fenbendazole and progesterone. Some critical operation parameters of the QuEChERS procedure were optimized by an experimental design but tetracycline, oxytetracycline, doxycycline, marbofloxacin and ciprofloxacin were not detected by the QuEChERS sample preparation. The use of a longer and thorough approach, a solid-liquid extraction with water/methanol in presence of primary secondary amine as a clean-up agent followed by solid-phase extraction on Oasis HLB cartridges, is recommended to monitor all intended analytes. The determination in extracts is carried out by ultra-high performance liquid chromatography-tandem mass spectrometry in selected reaction monitoring mode. Limits of detection about 0.2-42 ng per g of lyophilized microalgae sample, and repeatabilities about 6-46% (n = 5, RSDs) are reached. The solid-liquid extraction method was applied to microalgae biomass samples collected from a photobioreactor. Nine drugs were detected in the samples at relatively low concentration and a proportional relationship between the found concentrations and the octanol/water partition coefficients of the drugs has been outlined. Moreover, a linear ratio between the concentrations measured in biomass and effluent has been observed for most of the drugs.


Assuntos
Microalgas , Drogas Veterinárias , Biomassa , Cromatografia Líquida de Alta Pressão , Fotobiorreatores , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Águas Residuárias/análise
14.
Comput Methods Programs Biomed ; 213: 106459, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34768233

RESUMO

BACKGROUND AND OBJECTIVE: This paper presents an empirical study of a gamified mobile-based assessment approach that can be used to engage students and improve their educational performance. METHOD: A gamified audience response system called G-SIDRA was employed. Three gamification elements were used to motivate students in classroom activities: badges for achievements to increase engagement, points to indicate progression and performance in the subject and ranking for promoting competitiveness. A total of 90 medical students in a General and Descriptive Anatomy of the Locomotor System course were taught using G-SIDRA in the academic year 2019/2020. Smart bracelets were configured to collect heart rate measurements from 30 students with the aim of evaluating the impact of the gamification elements. The control group consisted of a sample of 110 students enrolled on the same course in the academic year 2016/2017 using non-gamified SIDRA. RESULTS: Statistically significant differences were found between multiple choice questions (MCQ) scores obtained by using SIDRA and G-SIDRA in the four experiments (U = 1.621,50, p < 0,01 for Exp1; U = 1.950,00, p < 0,01 for Exp2; U = 955,00, p < 0,01 for Exp3; U = 2.335,00, p < 0,01 for Exp4). In the students' final exam grades, statistically significant differences between students that used G-SIDRA as opposed to SIDRA (T(157) = 3.992; p = 0.044) were obtained. Concerning gamification elements, statistically significantly differences were found in comparing the pulse increases after and before the badge event in the four experiments (U = 2.484,00, p = 0,038 for Exp1; U = 2.109,50, p = 0,046 for Exp2; U = 1.790,50, p = 0,025 for Exp3; U = 1.557,0, p = 0,048 for Exp4). However, there are not statistically significant differences between the pulse increases after and before the ranking event in the four experiments. In a 5-point Likert-type scale, the students expressed satisfaction with G-SIDRA (M = 4.552) and thought the system helped to better understand both theoretical and practical concepts (M = 4.092). Their global assessment of the G-SIDRA platform was 4.471. CONCLUSIONS: Of the three gamification elements used in the study, only badge has an effect on heart rate. Better student responses and academic performance were achieved when using G-SIDRA. Nevertheless, more research is required to evaluate the impact of the gamification elements on the motivation, engagement and performance of students. Physiological measures are promising approaches for gamification elements evaluation.


Assuntos
Gamificação , Motivação , Frequência Cardíaca , Humanos
15.
Scand J Infect Dis ; 43(10): 814-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21671826

RESUMO

Data on catheter-related bloodstream infection (CRBSI) in cubital artery access are scarce. Thus, the objective of this study was to compare the incidence of CRBSI in a large series of patients with femoral or cubital artery catheters. We found 11 events of CRBSI in 1085 femoral artery catheters during 6497 days and none in 449 cubital artery catheters during 2709 days. Poisson regression analysis showed a higher incidence of CRBSI in femoral than in cubital artery site access (1.69 vs 0 CRBSI events per 1000 catheter-days; odds ratio 6.41, 95% confidence interval 1.05-infinite; p = 0.02). In conclusion, according to the results of our observational study, cubital artery access could have a lower risk of CRBSI than femoral artery access. However the development of randomized controlled trials is necessary before this conclusion can be definitively established. In addition, it is necessary to consider other potential mechanical complications when decision-making.


Assuntos
Bacteriemia/epidemiologia , Infecções Relacionadas a Cateter/epidemiologia , Cateterismo Venoso Central/métodos , Infecção Hospitalar/epidemiologia , Idoso , Bacteriemia/microbiologia , Bacteriemia/prevenção & controle , Infecções Relacionadas a Cateter/microbiologia , Infecções Relacionadas a Cateter/prevenção & controle , Cateterismo Venoso Central/estatística & dados numéricos , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Feminino , Artéria Femoral , Antebraço , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição de Poisson , Estudos Prospectivos , Análise de Regressão , Espanha/epidemiologia
16.
Appl Microbiol Biotechnol ; 89(1): 131-43, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20842358

RESUMO

Replacement of the signal peptide (SP) of the bacteriocins enterocin P (EntP) and hiracin JM79 (HirJM79), produced by Enterococcus faecium P13 and Enterococcus hirae DCH5, respectively, by the signal peptide of Usp45 (SP(usp45)), the major Sec-dependent protein secreted by Lactococcus lactis, permits the production, secretion, and functional expression of EntP and HirJM79 by L. lactis. Chimeric genes encoding the SP(usp45) fused to either mature EntP (entP), with or without the immunity gene (entiP) or to mature HirJM79 (hirJM79), with or without the immunity gene (hiriJM79), were cloned into the expression vector pMG36c, carrying the P(32) constitutive promoter, and into pNZ8048 under control of the inducible PnisA promoter. The production of EntP and HirJM79 by most of the L. lactis recombinant strains was 1.5- to 3.7-fold higher and up to 3.6-fold higher than by the E. faecium P13 and E. hirae DCH5 control strains, respectively. However, the specific antimicrobial activity of the recombinant EntP was 1.1- to 6.2-fold higher than that produced by E. faecium P13, while that of the HirJM79 was a 40% to an 89% of that produced by E. hirae DCH5. Chimeras of SP(usp45) fused to mature EntP or HirJM79 drive the production and secretion of these bacteriocins in L. lactis in the absence of specific immunity and secretion proteins. The supernatants of the recombinant L. lactis NZ9000 strains, producers of EntP, showed a much higher antimicrobial activity against Listeria spp. than that of the recombinant L. lactis NZ9000 derivatives, producers of HirJM79.


Assuntos
Bacteriocinas/genética , Bacteriocinas/metabolismo , Enterococcus faecium/metabolismo , Espaço Extracelular/metabolismo , Lactococcus lactis/genética , Engenharia de Proteínas , Sinais Direcionadores de Proteínas , Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Enterococcus faecium/genética , Espaço Extracelular/genética , Expressão Gênica , Lactococcus lactis/metabolismo , Transporte Proteico
17.
R Soc Open Sci ; 8(3): 201275, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33959314

RESUMO

Soil samples from several European countries were scanned using medical computer tomography (CT) device and are now available as CT images. The analysis of these samples was carried out using deep learning methods. For this purpose, a VGG16 network was trained with the CT images (X). For the annotation (y) a new method for automated annotation, 'surrogate' learning, was introduced. The generated neural networks (NNs) were subjected to a detailed analysis. Among other things, transfer learning was used to check whether the NN can also be trained to other y-values. Visually, the NN was verified using a gradient-based class activation mapping (grad-CAM) algorithm. These analyses showed that the NN was able to generalize, i.e. to capture the spatial structure of the soil sample. Possible applications of the models are discussed.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34948818

RESUMO

This paper presents three experiments to assess the impact of gamifying an audience response system on the perceptions and educational performance of students. An audience response system called SIDRA (Immediate Audience Response System in Spanish) and two audience response systems with gamification features, R-G-SIDRA (gamified SIDRA with ranking) and RB-G-SIDRA (gamified SIDRA with ranking and badges), were used in a General and Descriptive Human Anatomy course. Students participated in an empirical study. In the academic year 2019-2020, a total of 90 students used RB-G-SIDRA, 90 students employed R-G-SIDRA in the academic year 2018-2019, and 92 students used SIDRA in the academic year 2017-2018. Statistically significant differences were found between final exam grades obtained by using RB-G-SIDRA and SIDRA, U = 39.211 adjusted p = 0.001 and RB-G-SIDRA and R-G-SIDRA U = 31.157 adjusted p = 0.015, thus finding strong evidence with respect to the benefit of the badges used in RB-G-SIDRA. Moreover, in the students' SIDRA systems scores, statistically significant differences were found between RB-G-SIDRA and SIDRA, U = -90.521 adjusted p < 0.001, and between R-G-SIDRA and SIDRA, U = -87.998 adjusted p < 0.001. Significant correlations between individual and team scores were also found in all of the tests in RB-G-SIDRA and G-SIDRA. The students expressed satisfaction, engagement, and motivation with SIDRA, R-G-SIDRA, and RB-G-SIDRA, thus obtaining a final average assessment of 4.28, 4.61, and 4.47 out of 5, respectively. Students perform better academically with gamified versus non-gamified audience response systems. Findings can be used to build a gamified adaptive learning system.


Assuntos
Desempenho Acadêmico , Gamificação , Humanos , Aprendizagem , Motivação , Estudantes
19.
PLoS One ; 15(8): e0237115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785247

RESUMO

In this study the near-infrared reflectance (NIR) spectra signals (750-2,500 nm) of soil samples was compared with the NIR signals of the biogenic aggregates produced in the lab by three earthworm species, i.e., Aporrectodea rosea (Savigny 1826), Lumbricus friendi Cognetti, 1904 and Prosellodrilus pyrenaicus (Cognetti, 1904) from subalpine meadows in the Central Pyrenees. NIR spectral signatures of biogenic aggregates, root-aggregates, and non-aggregated soil were obtained together with soil carbon (C), nitrogen (N), [Formula: see text] and [Formula: see text] determinations. The concentrations of C, N and C:N ratio in the three types of soil aggregates identified were not statistically significant (ANOVA, p>0.05) although non-macroaggregated soil had slightly higher C concentrations (66.3 g kg-1 dry soil) than biogenic aggregates (earthworm- and root-aggregates, 64.9 and 63.5 g kg-1 dry soil, respectively), while concentrations of [Formula: see text] and [Formula: see text] were highest in the root-attached aggregates (3.3 and 0.31 mg kg dry soil-1). Total earthworm density and biomass in the sampled area was 137.6 ind. m-2, and 55.2 g fresh weight m-2, respectively. The biomass of aggregates attached to roots and non-macroaggregated soil was 122.3 and 134.8 g m-2, respectively, while biomass of free (particulate) organic matter and invertebrate biogenic aggregates was 62.9 and 41.7 g m-2, respectively. Multivariate analysis of NIR spectra signals of field aggregates separated root aggregates with high concentrations of [Formula: see text] and [Formula: see text] (41.5% of explained variance, axis I) from those biogenic aggregates, including root aggregates, with large concentrations of C and high C:N ratio (21.6% of total variability, axis II). Partial Least Square (PLS) regressions were used to compare NIR spectral signals of samples (casts and soil) and develop calibration equations relating these spectral data to those data obtained for chemical variables in the lab. After a derivatization process, the NIR spectra of field aggregates were projected onto the PLS factorial plane of the NIR spectra from the lab incubation. The projection of the NIR spectral signals onto the PLSR models for C, N, [Formula: see text] and [Formula: see text] from casts produced and incubated in the lab allowed us to identify the species and the age of the field biogenic aggregates. Our hypothesis was to test whether field aggregates would match or be in the vicinity of the NIR signals that corresponded to a certain species and the age of the depositions produced in the lab. A NIRS biogenic background noise (BBN) is present in the soil as a result of earthworm activity. This study provides insights on how to analyse the role of these organisms in important ecological processes of soil macro-aggregation and associated organic matter dynamics by means of analyzing the BBN in the soil matrix.


Assuntos
Pradaria , Oligoquetos/fisiologia , Solo/química , Altitude , Amônia/análise , Animais , Carbono/análise , Nitrogênio/análise , Solo/parasitologia , Espectroscopia de Luz Próxima ao Infravermelho
20.
Sci Total Environ ; 678: 94-104, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31075607

RESUMO

Total organic carbon (TOC) contents in agricultural soil are presently receiving increased attention, not only because of their relationship to soil fertility, but also due to the sequestration of organic carbon in soil to reduce carbon dioxide emissions. In this research, the spatial patterns of TOC and its relationship with pH at the European scale were studied using hot spot analysis based on the agricultural soil results of the Geochemical Mapping of Agricultural Soil (GEMAS) project. The hot and cold spot maps revealed the overall spatial patterns showing a negative correlation between TOC contents and pH values in European agricultural soil. High TOC contents accompanying low pH values in the north-eastern part of Europe (e.g., Fennoscandia), and low TOC with high pH values in the southern part (e.g., Spain, Italy, Balkan countries). A special feature of co-existence of comparatively low TOC contents and low pH values in north-central Europe was also identified on hot and cold spot analysis maps. It has been found that these patterns are strongly related to the high concentration of SiO2 (quartz) in the coarse-textured glacial sediments in north-central Europe. The hot spot analysis was effective, therefore, in highlighting the spatial patterns of TOC in European agricultural soil and helpful to identify hidden patterns.

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