1,530 research outputs found
Co-firing of biomass with coals Part 1. Thermogravimetric kinetic analysis of combustion of fir (abies bornmulleriana) wood
The chemical composition and reactivity of fir (Abies bornmulleriana) wood under non-isothermal thermogravimetric (TG) conditions were studied. Oxidation of the wood sample at temperatures near 600 A degrees C caused the loss of aliphatics from the structure of the wood and created a char heavily containing C-O functionalities and of highly aromatic character. On-line FTIR recordings of the combustion of wood indicated the oxidation of carbonaceous and hydrogen content of the wood and release of some hydrocarbons due to pyrolysis reactions that occurred during combustion of the wood. TG analysis was used to study combustion of fir wood. Non-isothermal TG data were used to evaluate the kinetics of the combustion of this carbonaceous material. The article reports application of Ozawa-Flynn-Wall model to deal with non-isothermal TG data for the evaluation of the activation energy corresponding to the combustion of the fir wood. The average activation energy related to fir wood combustion was 128.9 kJ/mol, and the average reaction order for the combustion of wood was calculated as 0.30
Early-transition-metal ketenimine complexes:Synthesis, reactivity, and structure of ketenimine-containing titanocene and zirconocene complexes
Reaction of Cp2M(PMe3)(2) complexes (M = Ti, Zr; Cp = eta(5)-C5H5) with the N-(p-tolyl)-diphenylketenimine Ph'N=C=CPh2 (Ph' = p-MeC6H4) in a 1:1 molar ratio affords the ketenimine-containing metallocene derivatives Cp2M(eta(2)-(C,N)-Ph'N=C=CPh2)(PMe3) (M = Ti (1); Zr (2)). The ketenimine ligand reacts in the same way with the ''Cp*M-2'' species (Cp* = eta(5)-C5Me5) generated from the reduction of the corresponding Cp*2MCl2 complexes with (LiBu)-Bu-t (1:2 molar ratio) to give the related complexes Cp*M-2(eta(2)-(C,N)-Ph'N=C=CPh2) (M = Ti (3); Zr (4)). The molecular structure of 3 shows a titanium atom bonded to two eta(5)-cyclopentadienyl rings and a eta(2)-(C,N)-bonded ketenimine ligand. Reaction of ''Cp*Ti-2'' with the ketenimine ligand in a 1:2 molar ratio gives 1,1,5,5-tetraphenyl-3-(p-tolyl)-2-(p-toluidino)-3-aza-1,4-pentadiene, which probably results from the coupling, followed by hydrolysis, of two ketenimine molecules coordinated to one titanocene moiety. Protonation of 3 with Et3NHCl or H2O (1:1 molar ratio) affords the intermediate species Cp*Ti-2(X)(eta(2)-(C,N)-Ph'N=C(H)=CPh2) (X = Cl (5); OH (6)), which on hydrolysis evolves to give the enamine Ph'N(H)-CH=CPh2 as the final product. Finally, 3 reacts reversibly with H-2 to give the hydride enamidate complex Cp*Ti-2(H)(eta(1)-Ph'N-CH=CPh2) (7). The structures of the different compounds have been determined by IR and NMR spectroscopic methods
Results of an Early Access Treatment Protocol of Daratumumab Monotherapy in Spanish Patients With Relapsed or Refractory Multiple Myeloma
Daratumumab is a human CD38-targeted monoclonal antibody approved as monotherapy for heavily pretreated relapsed and refractory multiple myeloma. We report findings for the Spanish cohort of an open-label treatment protocol that provided early access to daratumumab monotherapy and collected safety and patient-reported outcomes data for patients with relapsed or refractory multiple myeloma. At 15 centers across Spain, intravenous daratumumab (16 mg/kg) was administered to 73 patients who had >= 3 prior lines of therapy, including a proteasome inhibitor and an immunomodulatory drug, or who were double refractory to both. The median duration of daratumumab treatment was 3.3 (range: 0.03-13.17) months, with a median number of 12 (range: 1-25) infusions. Grade 3/4 treatment-emergent adverse events were reported in 74% of patients and included lymphopenia (28.8%), thrombocytopenia (27.4%), neutropenia (21.9%), leukopenia (19.2%), and anemia (15.1%). Common (>5%) serious treatmentemergent adverse events included respiratory tract infection (9.6%), general physical health deterioration (6.8%), and back pain (5.5%). Infusion-related reactions occurred in 45% of patients. The median change from baseline in all domains of the EQ-5D-5L and EORTC QLQ-C30 was mostly 0. A total of 18 (24.7%) patients achieved a partial response or better, with 10 (13.7%) patients achieving a very good partial response or better. Median progression-free survival was 3.98 months. The results of this early access treatment protocol are consistent with previously reported trials of daratumumab monotherapy and confirm its safety and antitumoral efficacy in Spanish patients with heavily treated relapsed or refractory multiple myeloma
A hierarchical network approach for modeling Rift Valley fever epidemics with applications in North America
Rift Valley fever is a vector-borne zoonotic disease which causes high
morbidity and mortality in livestock. In the event Rift Valley fever virus is
introduced to the United States or other non-endemic areas, understanding the
potential patterns of spread and the areas at risk based on disease vectors and
hosts will be vital for developing mitigation strategies. Presented here is a
general network-based mathematical model of Rift Valley fever. Given a lack of
empirical data on disease vector species and their vector competence, this
discrete time epidemic model uses stochastic parameters following several PERT
distributions to model the dynamic interactions between hosts and likely North
American mosquito vectors in dispersed geographic areas. Spatial effects and
climate factors are also addressed in the model. The model is applied to a
large directed asymmetric network of 3,621 nodes based on actual farms to
examine a hypothetical introduction to some counties of Texas, an important
ranching area in the United States of America (U.S.A.). The nodes of the
networks represent livestock farms, livestock markets, and feedlots, and the
links represent cattle movements and mosquito diffusion between different
nodes. Cattle and mosquito (Aedes and Culex) populations are treated with
different contact networks to assess virus propagation. Rift Valley fever virus
spread is assessed under various initial infection conditions (infected
mosquito eggs, adults or cattle). A surprising trend is fewer initial
infectious organisms result in a longer delay before a larger and more
prolonged outbreak. The delay is likely caused by a lack of herd immunity while
the infections expands geographically before becoming an epidemic involving
many dispersed farms and animals almost simultaneously
The effect of educational intervention on the disease knowledge of diabetes mellitus patients
The prevention of diabetes and its complications is a challenge for the healthcare team. The aim of this study was to evaluate the effect of educational action on the disease knowledge of patients with type 2 diabetes. A randomized clinical trial was conducted with 62 patients registered in a service of reference in the treatment of hypertension in 2010. Data were collected through a questionnaire applied to the Intervention (IG) and Control (CG) groups at the beginning and at the end of the study. The IG participated in group educational activities, using problematization methodology. The results showed a significant increase in knowledge about diabetes in the patients of the IG, in all the topics (pLa prevención de diabetes y sus complicaciones es un desafÃo para el equipo de salud. El objetivo de esta investigación fue evaluar el efecto de acción educativa sobre el conocimiento de la enfermedad en pacientes portadores de diabetes tipo 2. Fue realizado ensayo clÃnico aleatorizado con 62 pacientes registrados en servicio de referencia en tratamiento de la hipertensión arterial en 2010. Los datos fueron obtenidos a través de un cuestionario aplicado a los grupos Intervención (GI) y Control (GC), al inicio y al final del estudio. El GI participó de actividades educativas grupales, utilizando la metodologÃa problematizadora. Los resultados muestran un aumento significativo del conocimiento sobre la diabetes en pacientes del GI, en todas las cuestiones (pA prevenção do diabetes e suas complicações é um desafio para a equipe de saúde. O objetivo desta pesquisa foi avaliar o efeito de ação educativa sobre o conhecimento da doença em pacientes portadores de diabetes tipo 2. Foi realizado ensaio clÃnico randomizado com 62 pacientes cadastrados em serviço de referência para tratamento da hipertensão arterial, no ano 2010. Os dados foram obtidos através de questionário aplicado aos grupos intervenção (GI) e controle (GC), no momento inicial e no final do estudo. O GI participou de atividades educativas em grupo, utilizando a metodologia problematizadora. Os resultados mostraram aumento significativo do conhecimento sobre diabetes nos pacientes do GI, em todas as questões (p<0,05). No GC, algumas alterações observadas no conhecimento foram bem menores quando comparadas ao GI. Conclui-se que foi possÃvel elevar os conhecimentos sobre a doença por meio da realização de atividades educativas. O registro clÃnico obteve identificador primário: RBR-58n26
Industrial Systems Biology of Saccharomyces cerevisiae Enables Novel Succinic Acid Cell Factory.
Saccharomyces cerevisiae is the most well characterized eukaryote, the preferred microbial cell factory for the largest industrial biotechnology product (bioethanol), and a robust commerically compatible scaffold to be exploitted for diverse chemical production. Succinic acid is a highly sought after added-value chemical for which there is no native pre-disposition for production and accmulation in S. cerevisiae. The genome-scale metabolic network reconstruction of S. cerevisiae enabled in silico gene deletion predictions using an evolutionary programming method to couple biomass and succinate production. Glycine and serine, both essential amino acids required for biomass formation, are formed from both glycolytic and TCA cycle intermediates. Succinate formation results from the isocitrate lyase catalyzed conversion of isocitrate, and from the alpha-keto-glutarate dehydrogenase catalyzed conversion of alpha-keto-glutarate. Succinate is subsequently depleted by the succinate dehydrogenase complex. The metabolic engineering strategy identified included deletion of the primary succinate consuming reaction, Sdh3p, and interruption of glycolysis derived serine by deletion of 3-phosphoglycerate dehydrogenase, Ser3p/Ser33p. Pursuing these targets, a multi-gene deletion strain was constructed, and directed evolution with selection used to identify a succinate producing mutant. Physiological characterization coupled with integrated data analysis of transcriptome data in the metabolically engineered strain were used to identify 2nd-round metabolic engineering targets. The resulting strain represents a 30-fold improvement in succinate titer, and a 43-fold improvement in succinate yield on biomass, with only a 2.8-fold decrease in the specific growth rate compared to the reference strain. Intuitive genetic targets for either over-expression or interruption of succinate producing or consuming pathways, respectively, do not lead to increased succinate. Rather, we demonstrate how systems biology tools coupled with directed evolution and selection allows non-intuitive, rapid and substantial re-direction of carbon fluxes in S. cerevisiae, and hence show proof of concept that this is a potentially attractive cell factory for over-producing different platform chemicals
Chromosomal-level assembly of the Asian Seabass genome using long sequence reads and multi-layered scaffolding
We report here the ~670 Mb genome assembly of the Asian seabass (Lates calcarifer), a tropical marine teleost. We used long-read sequencing augmented by transcriptomics, optical and genetic mapping along with shared synteny from closely related fish species to derive a chromosome-level assembly with a contig N50 size over 1 Mb and scaffold N50 size over 25 Mb that span ~90% of the genome. The population structure of L. calcarifer species complex was analyzed by re-sequencing 61 individuals representing various regions across the species' native range. SNP analyses identified high levels of genetic diversity and confirmed earlier indications of a population stratification comprising three clades with signs of admixture apparent in the South-East Asian population. The quality of the Asian seabass genome assembly far exceeds that of any other fish species, and will serve as a new standard for fish genomics
Mineral and volatile composition of agua-mel from Portugal
Agua-mel (honey-water) is a typical honey-based product produced by the Portuguese beekeepers, particularly in southern Portugal. Agua-mel was characterized by mineral content and volatiles contents. Mineral content evaluation was performed based on a random sampling of 14 samples from a total of 16 samples provided by local producers. Mineral content showed that potassium predominated in agua-mel samples (1270-4105 mg/kg). The concentration of aluminium in one sample was tenfold higher (5.8 mg/kg) than in the remaining samples (0.3-0.6 mg/kg). Agua-mel volatiles were isolated by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) from a subset of eight samples. Cluster analysis showed two poorly correlated clusters (S (corr) < 0.3). Cluster I only sample was dominated by trans-beta-ocimene (19 %), gamma-terpinene (15 %) and 2-furfural (9 %). Cluster II that included the remaining seven samples showed two moderately correlated subclusters (S (corr) < 0.5). The six samples with high correlation from subcluster IIa were dominated by 2-furfural (18-41 %) and benzene acetaldehyde (12-39 %). n-Nonadecane (14 %), n-heneicosane and 2-furfural (both 13 %) were the main components of subcluster IIb sample. Although the presence of some volatile compounds can help in the correlation between agua-mel and honey botanical source, the final product varies largely according to the preparation process even for the same producer, in different years. Agua-mel detailed characterization may assist in bringing added value to this typical Portuguese honey-based product
The long-term outcomes of CIS patients in the Barcelona inception cohort: Looking back to recognize aggressive MS
OBJECTIVE:
To explore the long-term outcomes of patients with clinically isolated syndromes from the Barcelona cohort.
METHODS:
We selected patients with a follow-up longer than 10 years to (1) estimate the risks of multiple sclerosis (MS) and disability accumulation according to the baseline number of T2 lesions and to compare treated versus untreated patients and early versus delayed treatment, and (2) to study baseline features of patients with aggressive MS (Expanded Disability Status Scale (EDSS) ⩾6.0 at 10 years).
RESULTS:
In all, 401 patients were included (mean follow-up of 14.4 (standard deviation of 2.9) years). A higher number of T2 lesions was associated with an earlier MS diagnosis and an earlier risk of irreversible disability. Early treatment was associated with a decreased risk of EDSS of 3.0: adjusted hazard ratio = 0.4, 95% confidence interval = (0.2, 0.7). Patients with aggressive MS differed in their baseline brain magnetic resonance images: The median (interquartile range) number of T2 lesions and contrast-enhancing lesions (CEL) was 71 (28–95) versus 7 (1–19) and 3 (1–24) versus 0 (0–1), respectively. The cut-offs that better classified patients with aggressive MS were 20 for T2 lesions and 2 for CEL.
CONCLUSION:
Although MS natural history is changing, a high lesion load at onset is helpful to identify patients at risk of presenting an aggressive MS
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