15,379 research outputs found
Ultracapacitors for port crane applications: Sizing and techno-economic analysis
The use of energy storage with high power density and fast response time at container terminals (CTs) with a power demand of tens of megawatts is one of the most critical factors for peak reduction and economic benefits. Peak shaving can balance the load demand and facilitate the participation of small power units in generation based on renewable energies. Therefore, in this paper, the economic efficiency of peak demand reduction in ship to shore (STS) cranes based on the ultracapacitor (UC) energy storage sizing has been investigated. The results show the UC energy storage significantly reduce the peak demand, increasing the load factor, load leveling, and most importantly, an outstanding reduction in power and energy cost. In fact, the suggested approach is the start point to improve reliability and reduce peak demand energy consumption
Psychiatric genetics and the structure of psychopathology
For over a century, psychiatric disorders have been defined by expert opinion and clinical observation. The modern DSM has relied on a consensus of experts to define categorical syndromes based on clusters of symptoms and signs, and, to some extent, external validators, such as longitudinal course and response to treatment. In the absence of an established etiology, psychiatry has struggled to validate these descriptive syndromes, and to define the boundaries between disorders and between normal and pathologic variation. Recent advances in genomic research, coupled with large-scale collaborative efforts like the Psychiatric Genomics Consortium, have identified hundreds of common and rare genetic variations that contribute to a range of neuropsychiatric disorders. At the same time, they have begun to address deeper questions about the structure and classification of mental disorders: To what extent do genetic findings support or challenge our clinical nosology? Are there genetic boundaries between psychiatric and neurologic illness? Do the data support a boundary between disorder and normal variation? Is it possible to envision a nosology based on genetically informed disease mechanisms? This review provides an overview of conceptual issues and genetic findings that bear on the relationships among and boundaries between psychiatric disorders and other conditions. We highlight implications for the evolving classification of psychopathology and the challenges for clinical translation
Internet addiction: a systematic review of epidemiological research for the last decade
In the last decade, Internet usage has grown tremendously on a global scale. The increasing popularity and frequency of Internet use has led to an increasing number of reports highlighting the potential negative consequences of overuse. Over the last decade, research into Internet addiction has proliferated. This paper reviews the existing 68 epidemiological studies of Internet addiction that (i) contain quantitative empirical data, (ii) have been published after 2000, (iii) include an analysis relating to Internet addiction, (iv) include a minimum of 1000 participants, and (v) provide a full-text article published in English using the database Web of Science. Assessment tools and conceptualisations, prevalence, and associated factors in adolescents and adults are scrutinised. The results reveal the following. First, no gold standard of Internet addiction classification exists as 21 different assessment instruments have been identified. They adopt official criteria for substance use disorders or pathological gambling, no or few criteria relevant for an addiction diagnosis, time spent online, or resulting problems. Second, reported prevalence rates differ as a consequence of different assessment tools and cut-offs, ranging from 0.8% in Italy to 26.7% in Hong Kong. Third, Internet addiction is associated with a number of sociodemographic, Internet use, and psychosocial factors, as well as comorbid symptoms and disorder in adolescents and adults. The results indicate that a number of core symptoms (i.e., compulsive use, negative outcomes and salience) appear relevant for diagnosis, which assimilates Internet addiction and other addictive disorders and also differentiates them, implying a conceptualisation as syndrome with similar etiology and components, but different expressions of addictions. Limitations include the exclusion of studies with smaller sample sizes and studies focusing on specific online behaviours. Conclusively, there is a need for nosological precision so that ultimately those in need can be helped by translating the scientific evidence established in the context of Internet addiction into actual clinical practice
Halophiles and Their Biomolecules: Recent Advances and Future Applications in Biomedicine
The organisms thriving under extreme conditions better than any other organism living on Earth, fascinate by their hostile growing parameters, physiological features, and their production of valuable bioactive metabolites. This is the case of microorganisms (bacteria, archaea, and fungi) that grow optimally at high salinities and are able to produce biomolecules of pharmaceutical interest for therapeutic applications. As along as the microbiota is being approached by massive sequencing, novel insights are revealing the environmental conditions on which the compounds are produced in the microbial community without more stress than sharing the same substratum with their peers, the salt. In this review are reported the molecules described and produced by halophilic microorganisms with a spectrum of action in vitro: antimicrobial and anticancer. The action mechanisms of these molecules, the urgent need to introduce alternative lead compounds and the current aspects on the exploitation and its limitations are discussed.España, MINECO CGL2017-83385-
A review of information flow diagrammatic models for product-service systems
A product-service system (PSS) is a combination of products and services to
create value for both customers and manufacturers. Modelling a PSS based on
function orientation offers a useful way to distinguish system inputs and
outputs with regards to how data are consumed and information is used, i.e.
information flow. This article presents a review of diagrammatic information
flow tools, which are designed to describe a system through its functions. The
origin, concept and applications of these tools are investigated, followed by an
analysis of information flow modelling with regards to key PSS properties. A
case study of selection laser melting technology implemented as PSS will then be
used to show the application of information flow modelling for PSS design. A
discussion based on the usefulness of the tools in modelling the key elements of
PSS and possible future research directions are also presented
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Anaerobic 4-hydroxyproline utilization: Discovery of a new glycyl radical enzyme in the human gut microbiome uncovers a widespread microbial metabolic activity.
The discovery of enzymes responsible for previously unappreciated microbial metabolic pathways furthers our understanding of host-microbe and microbe-microbe interactions. We recently identified and characterized a new gut microbial glycyl radical enzyme (GRE) responsible for anaerobic metabolism of trans-4-hydroxy-l-proline (Hyp). Hyp dehydratase (HypD) catalyzes the removal of water from Hyp to generate Δ1-pyrroline-5-carboxylate (P5C). This enzyme is encoded in the genomes of a diverse set of gut anaerobes and is prevalent and abundant in healthy human stool metagenomes. Here, we discuss the roles HypD may play in different microbial metabolic pathways as well as the potential implications of this activity for colonization resistance and pathogenesis within the human gut. Finally, we present evidence of anaerobic Hyp metabolism in sediments through enrichment culturing of Hyp-degrading bacteria, highlighting the wide distribution of this pathway in anoxic environments beyond the human gut
GenomeFingerprinter and universal genome fingerprint analysis for systematic comparative genomics
How to compare whole genome sequences at large scale has not been achieved
via conventional methods based on pair-wisely base-to-base comparison;
nevertheless, no attention was paid to handle in-one-sitting a number of
genomes crossing genetic category (chromosome, plasmid, and phage) with farther
divergences (much less or no homologous) over large size ranges (from Kbp to
Mbp). We created a new method, GenomeFingerprinter, to unambiguously produce
three-dimensional coordinates from a sequence, followed by one
three-dimensional plot and six two-dimensional trajectory projections to
illustrate whole genome fingerprints. We further developed a set of concepts
and tools and thereby established a new method, universal genome fingerprint
analysis. We demonstrated their applications through case studies on over a
hundred of genome sequences. Particularly, we defined the total genetic
component configuration (TGCC) (i.e., chromosome, plasmid, and phage) for
describing a strain as a system, and the universal genome fingerprint map
(UGFM) of TGCC for differentiating a strain as a universal system, as well as
the systematic comparative genomics (SCG) for comparing in-one-sitting a number
of genomes crossing genetic category in diverse strains. By using UGFM,
UGFM-TGCC, and UGFM-TGCC-SCG, we compared a number of genome sequences with
farther divergences (chromosome, plasmid, and phage; bacterium, archaeal
bacterium, and virus) over large size ranges (6Kbp~5Mbp), giving new insights
into critical problematic issues in microbial genomics in the post-genomic era.
This paper provided a new method for rapidly computing, geometrically
visualizing, and intuitively comparing genome sequences at fingerprint level,
and hence established a new method of universal genome fingerprint analysis for
systematic comparative genomics.Comment: 63 pages, 15 figures, 5 table
Investigation into the impact of wind power generation on demand side management (DSM) practices
The construction of a number of wind farms in South Africa will lay the foundation for the
country to embrace the generation of greener energy into the National Grid. Despite the
benefits derived from introducing wind power generation into the grid, this source
encompasses adverse effects which need to be managed. These adverse effects include the
intermittency and lack of predictability of wind. In power systems with a high penetration of
wind energy, these effects can severely affect the power system’s security and reliability in
the event of significant rapid ramp rates. Recently, many utilities around the world have been
exploring the use of Demand Side Management (DSM) and Demand Response (DR)
initiatives and programmes to support and manage the intermittency of wind power
generation.
This report outlines the programmes and benefits of DSM/DR and provides a critical analysis
of the challenges facing South Africa with implementing these initiatives. Introducing these
programmes necessitates the employment of a number of Smart Grid technologies including
Advanced Metering Infrastructure (AMI), next generation telecommunications technologies,
smart meters, enterprise system integration and dynamic pricing. These tools and techniques
are discussed and their challenges described within the context of South Africa’s current state
of the power system. The current practices for DSM/DR in South Africa have been evaluated
in this report. Despite, the success of many DSM/DR initiatives in the commercial, industrial
and agricultural sectors, it is found that much work is still required in the residential sectors
as the current DSM initiatives are not adequate for managing wind power generation. A
detailed analysis and recommendations for South Africa’s DR program is then presented
based on industry best practices and experiences from other utilities who are currently
exploring DSM/DR in the residential sector using Smart Grid technologies
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