11 research outputs found
Mitigação de gás amônia por absorção reativa
No full textOdors from the decomposition of organic matter in rendering plants, bioenergy facilities, and composting plants cause notable environmental and health impacts in nearby communities due to the significant emission of ammonia gas, making the implementation of mitigation technologies essential. This study aimed to evaluate a pilot-scale reactive absorption column for treating a concentrated stream of ammonia gas and to simulate industrial-scale equipment. A coupled experimental and numerical investigation was conducted; a pilot-scale chemical scrubber was set up, and a 32 experimental design were performed with concentrations of ammonia and sulfuric acid as factors. The results demonstrated effective treatment with removal rates varying from 6.3% to 44.9%, with the limiting factor being the acid concentration in the scrubbing solution. Data were analysed using surface response methodology, and coupled numerical models were employed to determine the mass transfer coefficient and reaction rate constant. These data were regressed numerically and fitted into a microscopic mathematical model that accounted for both gas absorption by the liquid and the chemical reactions; this approach enabled the estimation of key parameters such as specific reaction rates and mass transfer. Finally, numerical studies were carried out to assess industrial-scale behaviour, explore scenarios for scale-up, predict equipment dimensions, and confirm the feasibility of industrial application. Results indicated that the industrial reactive absorption column could treat an ammonia stream flowing at approximately 27,000 m³/h (7.97kg/m3 of NH3) with near 100% efficiency.Odores provenientes da decomposição de matéria orgânica em graxarias, usinas bioenergéticas causam impactos ambientais e de saúde notáveis nas comunidades próximas, devido à emissão significativa de gás amônia, tornando essencial a implementação de tecnologias de mitigação. Este estudo teve como objetivo avaliar uma coluna de absorção reativa em escala piloto para o tratamento de um fluxo concentrado de gás amônia e simular equipamentos em escala industrial. Foi conduzida uma investigação combinada experimental e numérica; um absorvedor químico em escala piloto foi montado, e testes foram realizados com três concentrações diferentes de amônia e ácido sulfúrico. Os resultados demonstraram um tratamento eficaz, com taxas de remoção variáveis, sendo a concentração de ácido o fator limitante na solução de lavagem. Os dados foram analisados usando a metodologia de superfície de resposta, e modelos numéricos acoplados foram utilizados para determinar o coeficiente de transferência de massa e a constante de velocidade de reação. Estes dados foram ajustados numericamente e incorporados a um modelo matemático microscópico que considerou tanto a absorção do gás pela fase líquida quanto as reações químicas; esta abordagem permitiu estimar parâmetros-chave, como taxas de reação específicas e transferência de massa. Por fim, estudos numéricos foram realizados para avaliar o comportamento em escala industrial, explorar cenários de escalonamento, prever dimensões dos equipamentos e confirmar a viabilidade da aplicação industrial. Os resultados indicaram que a coluna de absorção reativa industrial poderia tratar um fluxo de amônia de aproximadamente 27.000 m³/h com eficiência próxima a 100%
Cello techniques and performing practices in the nineteenth and early twentieth centuries
No full textThis thesis comprises a study of cello performance practices throughout the nineteenth century and into the early decades of the twentieth. It is organised in terms of the increasing complexity of the concepts which it examines, as they are to be found in printed and manuscript music, instrumental methods and larger treatises, early recordings, concert reviews and pictures. Basic posture is considered along with different ways of holding the
bow. The development of the tail-pin shows that even when it was widely used, the older posture was still referred to as a model. Some implications for tone quality and tonal
projection are considered in the light of the shape of the arms. Some connections between the cellist's posture and that recommended by etiquette books are explored. The
functionality of the left hand and arm, and the development of modem scale fingerings, show that there was a considerable period of overlap between newer and older practices, with modern scale fingerings evolving over a long period of time. Similarly, views on the function of the right wrist in bowing are shown to change gradually, moving towards a more active upper arm movement with less extreme flexibility of the wrist. Two central expressive techniques especially associated with string playing arc considered in the context of the cello, namely vibrato and portamento. These topics are examined in the light of written indications in music, recommendations in cello treatises, and the practices evidenced in early recordings. The sources for this study can be brought into an overall
framework of a constant dialogue between `theory', as expressed in verbal instructions to the learner, or general a priori reflections about the cello, and `practice', manifested in performing editions and early recordings, or in individual acts of reception. A wide divergence is noted, both between theory and practice in general, and in terms of different styles of playing observable at any one time. It is suggested that tensions between practice
and critical disapproval can be resolved in terms of Lacanian discourse. Several test cases are used in order to compare several different recordings of the same works. The question of the musical character of the cello is discussed in terms of widespread assumptions about its gendered identity. A wide range of sources suggest that this moved from a straightforwardly `masculine' identity expressed through a controlling, elevated eloquence to a less clearly defined one, incorporating the 'feminine', with a greater stress on uninhibited emotional expression. Some performance implications for this change of view are pursued with respect to specific repertoires. Broad conclusions stress the importance of the diversity of performance practices as opposed to unifying generalisations
Author Correction: Comprehensive analysis of chromothripsis in 2,658 human cancers using whole-genome sequencing
No full textauthor correctio
Author Correction: Pan-cancer analysis of whole genomes
No full textCell adhesion molecules are ubiquitous in multicellular organisms, specifying precise cell-cell interactions in processes as diverse as tissue development, immune cell trafficking and the wiring of the nervous system(1-4). Here we show that a wide array of synthetic cell adhesion molecules can be generated by combining orthogonal extracellular interactions with intracellular domains from native adhesion molecules, such as cadherins and integrins. The resulting molecules yield customized cell-cell interactions with adhesion properties that are similar to native interactions. The identity of the intracellular domain of the synthetic cell adhesion molecules specifies interface morphology and mechanics, whereas diverse homotypic or heterotypic extracellular interaction domains independently specify the connectivity between cells. This toolkit of orthogonal adhesion molecules enables the rationally programmed assembly of multicellular architectures, as well as systematic remodelling of native tissues. The modularity of synthetic cell adhesion molecules provides fundamental insights into how distinct classes of cell-cell interfaces may have evolved. Overall, these tools offer powerful abilities for cell and tissue engineering and for systematically studying multicellular organization. Synthetic cell adhesion molecules yield customized cell-cell interactions with adhesion properties that are similar to native interactions, and offer abilities for cell and tissue engineering and for systematically studying multicellular organization
Author Correction: Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples
No full text: Correction to this paper has been published: https://doi.org/10.1038/s41467-020-20128-w
Performing practices in late-nineteenth-century piano playing
No full textEarly piano recordings provide audible evidence of the style of late- nineteenth and early twentieth century pianists. These clearly exhibit an approach to piano playing which differs radically from the present. The relationship between the practices preserved in the
recordings and their description in contemporaneous written texts is the focus of attention here. The investigation shows that the important features of recordings are not faithfully conveyed by the written texts. Therefore, the recordings reveal a manner of execution and interpretation that could seldom have been envisaged from the written texts alone.
The recordings examined here include those of a generation of pianists who were trained, in some cases, 150 years ago. These include Carl Reinecke, Theodor Leschetizky,Camille Saint-Satins, and Johannes Brahms, and those of a later generation have also been considered. Their recordings preserve vital information about general performing
practices of the second half of the nineteenth century, as well as the idiosyncrasies of their playing.
The significance of early recordings and their importance
as a means of appreciating lost traditions is outlined in the Introduction. Chapter 1 explores the early recording processes and draws conclusions about the value of the recordings as preserved evidence. The following chapters investigate practices that are prevalent in the recordings. These include dislocation (asynchrony of the hands), unnotated chordal arpeggiation, metrical rubato and various types of rhythmic alteration, and tempo modification. Each chapter compares contemporaneous and historical written references with numerous recorded examples provided on the accompanying compact discs. This process reveals, in many
cases, striking inconsistencies, and highlights the gulf between theory and practice. It also suggests that descriptive language and musical notation have hidden meanings for which the recordings provide an indispensable key.
Early piano recordings capture an expressive style alien to modern taste. The implications of this study are that any attempt at historically informed performances must
acknowledge the gulf between current aesthetics of performance and those of the late nineteenth and early-twentieth centuries
Distinct genetic liability profiles define clinically relevant patient strata across common diseases
No full textStratified medicine holds great promise to tailor treatment to the needs of individual patients. While genetics holds great potential to aid patient stratification, it remains a major challenge to operationalize complex genetic risk factor profiles to deconstruct clinical heterogeneity. Contemporary approaches to this problem rely on polygenic risk scores (PRS), which provide only limited clinical utility and lack a clear biological foundation. To overcome these limitations, we develop the CASTom-iGEx approach to stratify individuals based on the aggregated impact of their genetic risk factor profiles on tissue specific gene expression levels. The paradigmatic application of this approach to coronary artery disease or schizophrenia patient cohorts identified diverse strata or biotypes. These biotypes are characterized by distinct endophenotype profiles as well as clinical parameters and are fundamentally distinct from PRS based groupings. In stark contrast to the latter, the CASTom-iGEx strategy discovers biologically meaningful and clinically actionable patient subgroups, where complex genetic liabilities are not randomly distributed across individuals but rather converge onto distinct disease relevant biological processes. These results support the notion of different patient biotypes characterized by partially distinct pathomechanisms. Thus, the universally applicable approach presented here has the potential to constitute an important component of future personalized medicine paradigms. © The Author(s) 2024
Vibration as an exercise modality: how it may work, and what its potential might be
No full textWhilst exposure to vibration is traditionally
regarded as perilous, recent research has focussed on
potential benefits. Here, the physical principles of forced
oscillations are discussed in relation to vibration as an
exercise modality. Acute physiological responses to isolated
tendon and muscle vibration and to whole body
vibration exercise are reviewed, as well as the training
effects upon the musculature, bone mineral density and
posture. Possible applications in sports and medicine are
discussed. Evidence suggests that acute vibration exercise
seems to elicit a specific warm-up effect, and that vibration
training seems to improve muscle power, although the
potential benefits over traditional forms of resistive exercise
are still unclear. Vibration training also seems to
improve balance in sub-populations prone to fall, such as
frail elderly people. Moreover, literature suggests that
vibration is beneficial to reduce chronic lower back pain
and other types of pain. Other future indications are
perceivable
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Diversity Dimensions in Mathematics and Language Learning Perspectives on Culture, Education and Multilingualism
No full textExtensive research is available on language acquisition and the acquisition of mathematical skills in early childhood. But more recently, research has turned to the question of the influence of specific language aspects on acquisition of mathematical skills. This anthology combines current findings and theories from various disciplines such as (neuro- )psychology, linguistics, didactics and anthropology.
Wie hängen sprachliche und mathematische Entwicklung zusammen? Dieser Frage wird derzeit mit großem Interesse aus unterschiedlichen Perspektiven nachgegangen.Dieser Sammelband vereint Erkenntnisse aus Psychologie, Neurowissenschaften, Mathematikdidaktik, (Psycho-)Linguistik und Mehrsprachigkeitsforschung. Der interdisziplinäre Ansatz bietet einen umfassenden Blick auf den aktuellen Forschungsstand, dargestellt von national und international renommierten Forschenden.Das Buch gliedert sich in drei Teile. Der erste Teil "Modelle und Theorien" fasst theoretische Überlegungen zusammen und stellt Strukturen für Forschung und Praxis bereit. Dieser Teil dient dazu, den Grundstein für die anderen Teile sowie für zukünftige Forschung zu legen. Der zweite Teil "Kindergartenalter" sowie der dritte Teil "Grundschulalter" decken empirische Befunde über die Korrelation zwischen Sprache und mathematischem Lernen in der jeweiligen Altersgruppe ab. Ein besonderer Fokus liegt hierbei auf dem Aspekt der Mehrsprachigkeit.Damit bietet dieser Sammelband eine große Bandbreite fachspezifischen Wissens für Bildungswissenschaftler*innen, Lehramtsstudierende, Psycholog*innen und Forschende zur Mehrsprachigkeit
