Material Issues of the Metal Printing Process, MPP

The metal printing process, MPP; is a novel Rapid Manufacturing process under development at SINTEF and NTNU in Trondheim, Norway. The process, which aims at the manufacturing of end-use products for demanding applications in metallic and CerMet materials, consists of two separate parts; The layer fabrication, based on electrostatic attraction of powder materials, and the consolidation, consisting of the compression and sintering of each layer in a heated die. This approach leads to a number of issues regarding the interaction between the process solutions and the materials. This paper addresses some of the most critical material issues at the current development stage of MPP, and the present solutions to these.Mechanical Engineerin

Track reconstruction in the LHCb experiment

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Notes on determinations of nitrate in plant material.

The determination of nitrate in extracts of plants including grass, maize, sugarbeet leaves, lucerne, peas, cucumber, radish and lettuce by 3 different methods was tested. The methods based on nitration of O'-xylenol and dialysis of plant extracts and reduction of nitrate to nitrite ions by a Cu-Cd reductor were equally satisfactory. No influence of the extraction ratio was found. Extraction of plant material with water or electrolyte solution gave comparable results. Direct potentiometry gave too high results at lower nitrate ion levels. This phenomenon depends on the nature of plant material analysed and is apparently caused by organic anions. For spinach, the electrode can be used when the nitrate content is about 300 mmol nitrate/kg DM or higher. (Abstract retrieved from CAB Abstracts by CABI’s permission

Connectedness of healthcare professionals involved in the treatment of patients with Parkinson's disease: a social networks study

<p>Abstract</p> <p>Background</p> <p>Patients with chronic illness typically receive ambulatory treatment from multiple health professionals. Connectedness between these professionals may influence their clinical decisions and the coordination of patient care. We aimed to describe and analyze connectedness in a regional network of health professionals involved in ambulatory treatment of patients with Parkinson's disease (PD).</p> <p>Methods</p> <p>Observational study with 104 health professionals who had joined a newly established network (ParkinsonNet) were asked to complete a pre-structured form to report on their professional contacts with others in the network. Using social networks methods, network measures were calculated for the total network and for the networks of individual health professionals. We planned to test differences between subgroups of health professionals regarding 12 network measures, using a random permutation method.</p> <p>Results</p> <p>Ninety-six health professionals (92%) provided data on 101 professionals. The reciprocity of reported connections was 0.42 in the network of professional contacts. Measures characterizing the individual networks showed a wide variation; <it>e.g</it>., density varied between 0 and 100% (mean value 28.4%). Health professionals with ≥10 PD patients had higher values on 7 out of 12 network measures compare to those with < 10 PD patients (size, number of connections, two step reach, indegree centrality, outdegree centrality, inreach centrality, betweenness centrality). Primary care professionals had lower values on 11 out of 12 network measures (all but reach efficiency) compared to professionals who were affiliated with a hospital.</p> <p>Conclusions</p> <p>Our measure of professional connectedness proved to be feasible in a regional disease-specific network of health professionals. Network measures describing patterns in the professional contacts showed relevant variation across professionals. A higher caseload and an affiliation with a hospital were associated with stronger connectedness with other health professionals.</p

Ambiguity of human gene symbols in LocusLink and MEDLINE: creating an inventory and a disambiguation test collection

Genes are discovered almost on a daily basis and new names have to be found. Although there are guidelines for gene nomenclature, the naming process is highly creative. Human genes are often named with a gene symbol and a longer, more descriptive term; the short form is very often an abbreviation of the long form. Abbreviations in biomedical language are highly ambiguous, i.e., one gene symbol often refers to more than one gene.Using an existing abbreviation expansion algorithm,we explore MEDLINE for the use of human gene symbols derived from LocusLink. It turns out that just over 40% of these symbols occur in MEDLINE, however, many of these occurrences are not related to genes. Along the process of making an inventory, a disambiguation test collection is constructed automatically

Co-occurrence based meta-analysis of scientific texts: retrieving biological relationships between genes

MOTIVATION: The advent of high-throughput experiments in molecular biology creates a need for methods to efficiently extract and use information for large numbers of genes. Recently, the associative concept space (ACS) has been developed for the representation of information extracted from biomedical literature. The ACS is a Euclidean space in which thesaurus concepts are positioned and the distances between concepts indicates their relatedness. The ACS uses co-occurrence of concepts as a source of information. In this paper we evaluate how well the system can retrieve functionally related genes and we compare its performance with a simple gene co-occurrence method. RESULTS: To assess the performance of the ACS we composed a test set of five groups of functionally related genes. With the ACS good scores were obtained for four of the five groups. When compared to the gene co-occurrence method, the ACS is capable of revealing more functional biological relations and can achieve results with less literature available per gene. Hierarchical clustering was performed on the ACS output, as a potential aid to users, and was found to provide useful clusters. Our results suggest that the algorithm can be of value for researchers studying large numbers of genes. AVAILABILITY: The ACS program is available upon request from the authors

Ecdysteroid Hormones Link the Juvenile Environment to Alternative Adult Life Histories in a Seasonal Insect

The conditional expression of alternative life strategies is a widespread feature of animal life and a pivotal adaptation to life in seasonal environments. To optimally match suites of traits to seasonally changing ecological opportunities, animals living in seasonal environments need mechanisms linking information on environmental quality to resource allocation decisions. The butterfly Bicyclus anynana expresses alternative adult life histories in the alternating wet and dry seasons of its habitat as endpoints of divergent developmental pathways triggered by seasonal variation in preadult temperature. Pupal ecdysteroid hormone titers are correlated with the seasonal environment, but whether they play a functional role in coordinating the coupling of adult traits in the alternative life histories is unknown. Here, we show that manipulating pupal ecdysteroid levels is sufficient to mimic in direction and magnitude the shifts in adult reproductive resource allocation normally induced by seasonal temperature. Crucially, this allocation shift is accompanied by changes in ecologically relevant traits, including timing of reproduction, life span, and starvation resistance. Together, our results support a functional role for ecdysteroids during development in mediating strategic reproductive investment decisions in response to predictive indicators of environmental quality. This study provides a physiological mechanism for adaptive developmental plasticity, allowing organisms to cope with variable environments.European Union’s FP6 Programme (Network of Excellence LifeSpan FP6/036894), FCT fellowship (SFRH/BD/45486/2008)

N-acetylcysteine (NAC) and Hydrogen Sulfide (H₂S) in Coronavirus Disease 2019 (COVID-19)

Significance: Hydrogen sulfide (H2S) is one of the three main gasotransmitters which is endogenously produced in humans and is protective against oxidative stress. Recent findings from studies focusing on coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), shifted our attention to a potential modulatory role of H2S in this viral respiratory disease. Recent Advances: H2S levels at hospital admission may be of importance since this gasotransmitter has been shown to be protective against lung damage through its antiviral, antioxidant and anti-inflammatory actions. Furthermore, many COVID-19 cases have been described demonstrating remarkable clinical improvement upon administration of high doses of N-acetylcysteine (NAC). NAC is a renowned pharmacological antioxidant substance acting as a source of cysteine, thereby promoting endogenous glutathione (GSH) biosynthesis as well as generation of sulfane sulfur species when desulfurated to H2S. Critical Issues: Combining H2S physiology and currently available knowledge of COVID-19, H2S is hypothesized to target three main vulnerabilities of SARS-CoV-2: 1) cell entry through interfering with functional host receptors, 2) viral replication through acting on RNA-dependent RNA-polymerase (RdRp), and 3) the escalation of inflammation to a potentially lethal hyperinflammatory cytokine storm (TLR4 pathway and NLRP3 inflammasome). Future Directions: Dissecting the breakdown of NAC reveals the possibility of increasing endogenous H2S levels, which may provide a convenient rationale for the application of H2S-targeted therapeutics. Further randomized controlled trials (RCT) are warranted to investigate its definitive role