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1.
Micromachines (Basel) ; 14(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37421043

RESUMO

A graphene/poly(methyl methacrylate) (PMMA) closed cavity resonator with a resonant frequency at around 160 kHz has been fabricated. A six-layer graphene structure with a 450 nm PMMA laminated layer has been dry-transferred onto the closed cavity with an air gap of 105 µm. The resonator has been actuated in an atmosphere and at room temperature by mechanical, electrostatic and electro-thermal methods. The (1,1) mode has been observed to dominate the resonance, which suggests that the graphene/PMMA membrane has been perfectly clamped and seals the closed cavity. The degree of linearity of the membrane's displacement versus the actuation signal has been determined. The resonant frequency has been observed to be tuned to around 4% by applying an AC voltage through the membrane. The strain has been estimated to be around 0.08%. This research puts forward a graphene-based sensor design for acoustic sensing.

2.
Rev Fish Biol Fish ; 32(1): 123-143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33589856

RESUMO

Improved public understanding of the ocean and the importance of sustainable ocean use, or ocean literacy, is essential for achieving global commitments to sustainable development by 2030 and beyond. However, growing human populations (particularly in mega-cities), urbanisation and socio-economic disparity threaten opportunities for people to engage and connect directly with ocean environments. Thus, a major challenge in engaging the whole of society in achieving ocean sustainability by 2030 is to develop strategies to improve societal connections to the ocean. The concept of ocean literacy reflects public understanding of the ocean, but is also an indication of connections to, and attitudes and behaviours towards, the ocean. Improving and progressing global ocean literacy has potential to catalyse the behaviour changes necessary for achieving a sustainable future. As part of the Future Seas project (https://futureseas2030.org/), this paper aims to synthesise knowledge and perspectives on ocean literacy from a range of disciplines, including but not exclusive to marine biology, socio-ecology, philosophy, technology, psychology, oceanography and human health. Using examples from the literature, we outline the potential for positive change towards a sustainable future based on knowledge that already exists. We focus on four drivers that can influence and improve ocean literacy and societal connections to the ocean: (1) education, (2) cultural connections, (3) technological developments, and (4) knowledge exchange and science-policy interconnections. We explore how each driver plays a role in improving perceptions of the ocean to engender more widespread societal support for effective ocean management and conservation. In doing so, we develop an ocean literacy toolkit, a practical resource for enhancing ocean connections across a broad range of contexts worldwide.

3.
Rev Fish Biol Fish ; 32(1): 209-230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33500602

RESUMO

Abstract: The ocean economy is experiencing rapid growth that will provide benefits but will also pose environmental and social risks. With limited space and degraded resources in coastal areas, offshore waters will be a particular focus of Blue Economy expansion over the next decade. When emerging and established economic sectors expand in offshore waters (within national Exclusive Economic Zones), different potential Blue Economy opportunities and challenges will arise. Following a series of interdisciplinary workshops, we imagine two technically possible futures for the offshore Blue Economy and we identify the actions required to achieve the more sustainable outcome. Under a business as usual scenario the focus will remain on economic growth, the commodification of nature, the dominance of private over public and cultural interests, and prioritisation of the interests of current over future generations. A more sustainable scenario would meet multiple UN Sustainable Development Goals and ensure inclusive economic developments, environmental sustainability, and fair and equitable access to resources and technologies across users, nations, and generations. Challenges to this more sustainable future are a lack of infrastructure and technology to support emerging offshore sectors, limited understanding of environmental impacts, inequitable outcomes, and a lack of planning and governmental oversight. Addressing these challenges will require a shift in societal values, a more balanced allocation of funding to offshore activities, transparency in information sharing between industries and across nations, and adjustment of international legal and institutional mechanisms. The sustainable and equitable offshore Blue Economy we envisage is achievable and provides a unique opportunity to build global capacity and partnership.

4.
ACS Appl Mater Interfaces ; 13(32): 38792-38798, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34337933

RESUMO

We report the realization of an acoustic capacitive microphone formed by graphene/poly(methyl methacrylate) (PMMA). It is the first time that the ultra-large graphene/PMMA membrane suspended fully over the cavity has been fabricated by releasing the silicon dioxide sacrificial layer underneath the membrane. The novelty in the fabrication method is that the silicon dioxide layer has been etched by hydrogen fluoride vapor from the back of the partly etched silicon substrate. Using the new process, the ultra-large graphene/PMMA membrane, with a diameter to thickness ratio of 7800, has been suspended over the cavity with a 2 µm air gap. The spacing of 2 µm is the minimum gap over the graphene-based acoustic capacitive microphones which have been reported so far. The static deformation of the suspended graphene/PMMA membrane after silicon dioxide has been etched is estimated to be 270 nm. The aspect ratio of the membrane's diameter over its static deformation is around 13,000, which shows that the graphene/PMMA membrane with a diameter of a few millimeters can be transferred and suspended over the substrate with relatively small deformation by releasing the sacrificial silicon dioxide layer. The dynamic behavior of the device under electrostatic actuation has been characterized. The acoustic response of the graphene/PMMA capacitive microphone has been measured, and the sensitivity has been observed to be -47.5 dB V (4.22 mV/Pa) ± 10%. The strain in the graphene/PMMA membrane is estimated to be 0.034%.

5.
PLoS One ; 15(4): e0219882, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32243481

RESUMO

Microbial community profiles have been associated with a variety of traits, including methane emissions in livestock. These profiles can be difficult and expensive to obtain for thousands of samples (e.g. for accurate association of microbial profiles with traits), therefore the objective of this work was to develop a low-cost, high-throughput approach to capture the diversity of the rumen microbiome. Restriction enzyme reduced representation sequencing (RE-RRS) using ApeKI or PstI, and two bioinformatic pipelines (reference-based and reference-free) were compared to bacterial 16S rRNA gene sequencing using repeated samples collected two weeks apart from 118 sheep that were phenotypically extreme (60 high and 58 low) for methane emitted per kg dry matter intake (n = 236). DNA was extracted from freeze-dried rumen samples using a phenol chloroform and bead-beating protocol prior to RE-RRS. The resulting sequences were used to investigate the repeatability of the rumen microbial community profiles, the effect of laboratory and analytical method, and the relationship with methane production. The results suggested that the best method was PstI RE-RRS analyzed with the reference-free approach, which accounted for 53.3±5.9% of reads, and had repeatabilities of 0.49±0.07 and 0.50±0.07 for the first two principal components (PC1 and PC2), phenotypic correlations with methane yield of 0.43±0.06 and 0.46±0.06 for PC1 and PC2, and explained 41±8% of the variation in methane yield. These results were significantly better than for bacterial 16S rRNA gene sequencing of the same samples (p<0.05) except for the correlation between PC2 and methane yield. A Sensitivity study suggested approximately 2000 samples could be sequenced in a single lane on an Illumina HiSeq 2500, meaning the current work using 118 samples/lane and future proposed 384 samples/lane are well within that threshold. With minor adaptations, our approach could be used to obtain microbial profiles from other metagenomic samples.


Assuntos
Microbioma Gastrointestinal , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenômica/métodos , Rúmen/microbiologia , Ovinos/microbiologia , Animais , Bactérias/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/economia , Masculino , Metagenoma , Metagenômica/economia , Microbiota , RNA Ribossômico 16S/genética
6.
BMJ Open ; 8(9): e022452, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30224390

RESUMO

INTRODUCTION: Inflammation and dysregulated immune responses play a crucial role in atherosclerosis, underlying ischaemic heart disease (IHD) and acute coronary syndromes (ACSs). Immune responses are also major determinants of the postischaemic injury in myocardial infarction. Regulatory T cells (CD4+CD25+FOXP3+; Treg) induce immune tolerance and preserve immune homeostasis. Recent in vivo studies suggested that low-dose interleukin-2 (IL-2) can increase Treg cell numbers. Aldesleukin is a human recombinant form of IL-2 that has been used therapeutically in several autoimmune diseases. However, its safety and efficacy is unknown in the setting of coronary artery disease. METHOD AND ANALYSIS: Low-dose interleukin-2 in patients with stable ischaemic heart disease and acute coronary syndromes is a single-centre, first-in-class, dose-escalation, two-part clinical trial. Patients with stable IHD (part A) and ACS (part B) will be randomised to receive either IL-2 (aldesleukin; dose range 0.3-3×106 IU) or placebo once daily, given subcutaneously, for five consecutive days. Part A will have five dose levels with five patients in each group. Group 1 will receive a dose of 0.3×106 IU, while the dose for the remaining four groups will be determined on completion of the preceding group. Part B will have four dose levels with eight patients in each group. The dose of the first group will be based on part A. Doses for each of the subsequent three groups will similarly be determined after completion of the previous group. The primary endpoint is safety and tolerability of aldesleukin and to determine the dose that increases mean circulating Treg levels by at least 75%. ETHICS AND DISSEMINATION: The study received a favourable opinion by the Greater Manchester Central Research Ethics Committee, UK (17/NW/0012). The results of this study will be reported through peer-reviewed journals, conference presentations and an internal organisational report. TRIAL REGISTRATION NUMBER: NCT03113773; Pre-results.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Fatores Imunológicos/efeitos adversos , Interleucina-2/análogos & derivados , Isquemia Miocárdica/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Linfócitos T Reguladores/efeitos dos fármacos , Síndrome Coronariana Aguda/sangue , Proteína C-Reativa/metabolismo , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Método Duplo-Cego , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/sangue , Interleucina-2/administração & dosagem , Interleucina-2/efeitos adversos , Interleucina-2/sangue , Interleucina-6/sangue , Contagem de Linfócitos , Isquemia Miocárdica/sangue , Peptídeo Natriurético Encefálico/sangue , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/sangue , Troponina/sangue
7.
Br J Oral Maxillofac Surg ; 54(8): 927-929, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27389371

RESUMO

We describe an anatomical and simple technique for the removal of the submandibular gland that has good outcomes and minimal complications.


Assuntos
Glândula Sublingual/cirurgia , Dissecação , Humanos , Glândula Submandibular
8.
PeerJ ; 4: e1591, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26819848

RESUMO

Sacbrood virus (SBV) and Deformed wing virus (DWV) are evolutionarily related positive-strand RNA viruses, members of the Iflavirus group. They both infect the honeybee Apis mellifera but have strikingly different levels of virulence when transmitted orally. Honeybee larvae orally infected with SBV usually accumulate high levels of the virus, which halts larval development and causes insect death. In contrast, oral DWV infection at the larval stage usually causes asymptomatic infection with low levels of the virus, although high doses of ingested DWV could lead to DWV replicating to high levels. We investigated effects of DWV and SBV infection on the transcriptome of honeybee larvae and pupae using global RNA-Seq and real-time PCR analysis. This showed that high levels of SBV replication resulted in down-regulation of the genes involved in cuticle and muscle development, together with changes in expression of putative immune-related genes. In particular, honeybee larvae with high levels of SBV replication, with and without high levels of DWV replication, showed concerted up-regulated expression of antimicrobial peptides (AMPs), and down-regulated expression of the prophenoloxidase activating enzyme (PPAE) together with up-regulation of the expression of a putative serpin, which could lead to the suppression of the melanisation pathway. The effects of high SBV levels on expression of these immune genes were unlikely to be a consequence of SBV-induced developmental changes, because similar effects were observed in honeybee pupae infected by injection. In the orally infected larvae with high levels of DWV replication alone we observed no changes of AMPs or of gene expression in the melanisation pathway. In the injected pupae, high levels of DWV alone did not alter expression of the tested melanisation pathway genes, but resulted in up-regulation of the AMPs, which could be attributed to the effect of DWV on the regulation of AMP expression in response to wounding. We propose that the difference in expression of the honeybee immune genes induced by SBV and DWV may be an evolutionary adaptation to the different predominant transmission routes used by these viruses.

9.
Micromachines (Basel) ; 7(11)2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30404380

RESUMO

In the drive to miniaturise and integrate reference oscillator components, microelectromechanical systems (MEMS) resonators are excellent candidates to replace quartz crystals. Silicon is the most utilised resonator structural material due to its associated well-established fabrication processes. However, when operation in harsh environments is required, cubic silicon carbide (3C-SiC) is an excellent candidate for use as a structural material, due to its robustness, chemical inertness and high temperature stability. In order to actuate 3C-SiC resonators, electrostatic, electrothermal and piezoelectric methods have been explored. Both electrothermal and piezoelectric actuation can be accomplished with simpler fabrication and lower driving voltages, down to 0.5 V, compared to electrostatic actuation. The vibration amplitude at resonance can be maximised by optimising the design and location of the electrodes. Electrical read out of the resonator can be performed with electrostatic or piezoelectric transduction. Finally, a great deal of research has focused on tuning the resonant frequency of a 3C-SiC resonator by adjusting the DC bias applied to the electrodes, with a higher (up to 160-times) tuning range for electrothermal tuning compared to piezoelectric tuning. Electrothermal tuning lowers the frequency, while piezoelectric tuning can be used to raise the frequency.

10.
J Environ Manage ; 160: 241-53, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26119331

RESUMO

Environmental Impact Assessment (EIA) is a key tool to help ensure sustainable built development in more than 200 countries worldwide. Ecology is frequently a component of EIA and early reviews of Ecological Impact Assessment (EcIA) chapters identified scope for improvement at almost every stage of the EcIA process, regardless of country. However, there have been no reviews of UK EcIA chapters since 2000, despite important changes in biodiversity and planning legislation, policy and guidance. In addition, no UK EcIA chapter reviews have attempted to assign a grade or score to EcIA chapters (as has been done for reviews of US, Finnish and Indian EcIA chapters). Furthermore, no EcIA chapter reviews have attempted to use a scoring system to identify which variables determine EcIA chapter information content, beyond straightforward comparisons of EcIA chapters before and after the introduction of guidelines. A variant of the Biodiversity Assessment Index (BAI) was used to assign scores between zero and one to EcIA chapters based on a series of 47 questions drawn from EU legislation and professional guidance. 112 EcIA chapters for proposed developments that were subsequently granted planning permission in England were assessed. The mean BAI score was less than 0.5, indicating the presence of considerable information gaps in the majority of EcIA chapters. Of 13 predictor variables identified as having the potential to affect EcIA chapter quality, 10 were identified as significantly related to the BAI scores. A backward stepwise Generalized Linear Model identified the use of professional guidance, the ecological consultancy type and the length of the EcIA chapter as having the greatest combined explanatory power. As a result, several recommendations are made to help improve future EcIA chapter content, including formal EcIA chapter review, publicising the professional guidance to consultants, the provision of training and the introduction of an accreditation scheme for consultants involved in EcIA This approach could be replicated in other countries that conduct EIA. Context-dependent EcIA chapter review criteria (as in this paper) would help to identify targeted recommendations for improvement. Alternatively, a global set of review criteria could highlight areas of best practice that could then be exported to other countries.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Meio Ambiente , Humanos , Políticas , Reino Unido
11.
Behav Brain Sci ; 37(5): 504-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25388053

RESUMO

The inherence heuristic is characterized as part of an instantiation of a more general model that describes the interaction between undeveloped intuitions, produced by System 1 heuristics, and developed beliefs, constructed by System 2 reasoning. The general model is described and illustrated by examining another instantiation of the process that constructs belief in objective moral value.


Assuntos
Cognição , Formação de Conceito , Aprendizagem , Lógica , Humanos
12.
PeerJ ; 2: e645, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25405074

RESUMO

The impetus for this work was the need to analyse nucleotide diversity in a viral mix taken from honeybees. The paper has two findings. First, a method for correction of next generation sequencing error in the distribution of nucleotides at a site is developed. Second, a package of methods for assessment of nucleotide diversity is assembled. The error correction method is statistically based and works at the level of the nucleotide distribution rather than the level of individual nucleotides. The method relies on an error model and a sample of known viral genotypes that is used for model calibration. A compendium of existing and new diversity analysis tools is also presented, allowing hypotheses about diversity and mean diversity to be tested and associated confidence intervals to be calculated. The methods are illustrated using honeybee viral samples. Software in both Excel and Matlab and a guide are available at http://www2.warwick.ac.uk/fac/sci/systemsbiology/research/software/, the Warwick University Systems Biology Centre software download site.

13.
Nucleic Acids Res ; 42(16): e123, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25120266

RESUMO

Viral recombination is a key evolutionary mechanism, aiding escape from host immunity, contributing to changes in tropism and possibly assisting transmission across species barriers. The ability to determine whether recombination has occurred and to locate associated specific recombination junctions is thus of major importance in understanding emerging diseases and pathogenesis. This paper describes a method for determining recombinant mosaics (and their proportions) originating from two parent genomes, using high-throughput sequence data. The method involves setting the problem geometrically and the use of appropriately constrained quadratic programming. Recombinants of the honeybee deformed wing virus and the Varroa destructor virus-1 are inferred to illustrate the method from both siRNAs and reads sampling the viral genome population (cDNA library); our results are confirmed experimentally. Matlab software (MosaicSolver) is available.


Assuntos
Genoma Viral , Recombinação Genética , Software , Algoritmos , Sequenciamento de Nucleotídeos em Larga Escala , RNA Interferente Pequeno/química
14.
PLoS Pathog ; 10(6): e1004230, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24968198

RESUMO

The globally distributed ectoparasite Varroa destructor is a vector for viral pathogens of the Western honeybee (Apis mellifera), in particular the Iflavirus Deformed Wing Virus (DWV). In the absence of Varroa low levels DWV occur, generally causing asymptomatic infections. Conversely, Varroa-infested colonies show markedly elevated virus levels, increased overwintering colony losses, with impairment of pupal development and symptomatic workers. To determine whether changes in the virus population were due Varroa amplifying and introducing virulent virus strains and/or suppressing the host immune responses, we exposed Varroa-naïve larvae to oral and Varroa-transmitted DWV. We monitored virus levels and diversity in developing pupae and associated Varroa, the resulting RNAi response and transcriptome changes in the host. Exposed pupae were stratified by Varroa association (presence/absence) and virus levels (low/high) into three groups. Varroa-free pupae all exhibited low levels of a highly diverse DWV population, with those exposed per os (group NV) exhibiting changes in the population composition. Varroa-associated pupae exhibited either low levels of a diverse DWV population (group VL) or high levels of a near-clonal virulent variant of DWV (group VH). These groups and unexposed controls (C) could be also discriminated by principal component analysis of the transcriptome changes observed, which included several genes involved in development and the immune response. All Varroa tested contained a diverse replicating DWV population implying the virulent variant present in group VH, and predominating in RNA-seq analysis of temporally and geographically separate Varroa-infested colonies, was selected upon transmission from Varroa, a conclusion supported by direct injection of pupae in vitro with mixed virus populations. Identification of a virulent variant of DWV, the role of Varroa in its transmission and the resulting host transcriptome changes furthers our understanding of this important viral pathogen of honeybees.


Assuntos
Vetores Aracnídeos/virologia , Abelhas/parasitologia , Abelhas/virologia , Interações Hospedeiro-Patógeno , Picornaviridae/patogenicidade , Varroidae/virologia , Animais , Vetores Aracnídeos/crescimento & desenvolvimento , Vetores Aracnídeos/imunologia , Abelhas/imunologia , Abelhas/metabolismo , Feminino , Interações Hospedeiro-Parasita , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Larva/imunologia , Larva/metabolismo , Larva/parasitologia , Larva/virologia , Masculino , Picornaviridae/imunologia , Picornaviridae/isolamento & purificação , Análise de Componente Principal , Pupa/imunologia , Pupa/metabolismo , Pupa/parasitologia , Pupa/virologia , Interferência de RNA , Especificidade da Espécie , Transcriptoma , Varroidae/crescimento & desenvolvimento , Varroidae/imunologia , Carga Viral/veterinária , Virulência
15.
Med Probl Perform Art ; 29(1): 37-45, 2014 03.
Artigo em Inglês | MEDLINE | ID: mdl-24647461

RESUMO

This study explores performance-related medical disorders (PRMD) among a sample of tertiary-trained jazz pianists. Participants included both Australian and US pianists (n=214), including current and former tertiary students, professional pianists, and teachers. This mixed methods (quantitative and qualitative) exploratory and descriptive study used survey and case studies to provide baseline data for further research. Students reported a past and present period prevalence of 63% for pain and 41% for PRMD (injury attributed to practice or performance) with the forearm being the body part most affected, usually by fatigue. Diagnosis and treatment were reported as often unsatisfactory mainly due to lack of knowledge of PRMD by teachers and by professional health providers, and also to limited access to specialist PRMD services where these exist. Although teacher knowledge of PRMD is quite low, students still seek advice primarily from their teachers. The current study highlights a need to address the issue of PRMD among jazz pianists and their teachers more strategically, both in its prevention and in diagnosis and treatment.


Assuntos
Nível de Saúde , Dor Musculoesquelética/epidemiologia , Música , Doenças Profissionais/epidemiologia , Traumatismos Ocupacionais/epidemiologia , Índice de Gravidade de Doença , Adulto , Austrália/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Musculoesquelética/prevenção & controle , Doenças Profissionais/prevenção & controle , Saúde Ocupacional/estatística & dados numéricos , Traumatismos Ocupacionais/prevenção & controle , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia , Local de Trabalho
16.
Adv Bioinformatics ; 2011: 176813, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21687643

RESUMO

Peptides fold on a time scale that is much smaller than the time required for synthesis, whence all proteins potentially fold cotranslationally to some degree (followed by additional folding events after release from the ribosome). In this paper, in three different ways, we find that cotranslational folding success is associated with higher hydrophobicity at the N-terminus than at the C-terminus. First, we fold simple HP models on a square lattice and observe that HP sequences that fold better cotranslationally than from a fully extended state exhibit a positive difference (N-C) in terminus hydrophobicity. Second, we examine real proteins using a previously established measure of potential cotranslationality known as ALR (Average Logarithmic Ratio of the extent of previous contacts) and again find a correlation with the difference in terminus hydrophobicity. Finally, we use the cotranslational protein structure prediction program SAINT and again find that such an approach to folding is more successful for proteins with higher N-terminus than C-terminus hydrophobicity. All results indicate that cotranslational folding is promoted in part by a hydrophobic start and a less hydrophobic finish to the sequence.

17.
Bioinformatics ; 26(15): 1849-56, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20525820

RESUMO

MOTIVATION: Template-based modelling can approximate the unknown structure of a target protein using an homologous template structure. The core of the resulting prediction then comprises the structural regions conserved between template and target. Target prediction could be improved by rigidly repositioning such single template, structurally conserved fragment regions. The purpose of this article is to quantify the extent to which such improvements are possible and to relate this extent to properties of the target, the template and their alignment. RESULTS: The improvement in accuracy achievable when rigid fragments from a single template are optimally positioned was calculated using structure pairs from the HOMSTRAD database, as well as CASP7 and CASP8 target/best template pairs. Over the union of the structurally conserved regions, improvements of 0.7 A in root mean squared deviation (RMSD) and 6% in GDT_HA were commonly observed. A generalized linear model revealed that the extent to which a template can be improved can be predicted using four variables. Templates with the greatest scope for improvement tend to have relatively more fragments, shorter fragments, higher percentage of helical secondary structure and lower sequence identity. Optimal positioning of the template fragments offers the potential for improving loop modelling. These results demonstrate that substantial improvement could be made on many templates if the conserved fragments were to be optimally positioned. They also provide a basis for identifying templates for which modification of fragment positions may yield such improvements.


Assuntos
Biologia Computacional/métodos , Modelos Moleculares , Algoritmos , Proteínas/química , Alinhamento de Sequência/métodos
18.
Clin Lab ; 56(1-2): 9-19, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20380355

RESUMO

BACKGROUND: The blood count is widely used in clinical practice. Well defined reference intervals for each measurand are essential for correct clinical interpretation of results. Most previous studies have not been population-based. We therefore calculated reference intervals for several hematological measurands from a sample of the general adult population of Northeastern Germany. METHODS AND RESULTS: We used data from 2967 healthy individuals recruited for the population-based Study of Health in Pomerania (SHIP). Reference intervals were calculated according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI) using the bootstrap method for the age range from 20 to 79 years and, in addition, stratified according to age and gender with both bootstrap and quantile regression procedures. Reference ranges for erythrocytes, hemoglobin and hematocrit increased with age in women but decreased in men. CONCLUSIONS: Our reference intervals were lower than those previously published for erythrocytes, hemoglobin, hematocrit and leukocytes but higher for Mean Corpuscular Volume (MCV) and Mean Corpuscular Hemoglobin (MCH). Different laboratory methods and study populations may lead to disparity in results.


Assuntos
Contagem de Células Sanguíneas/métodos , Adulto , Fatores Etários , Idoso , Envelhecimento/fisiologia , Contagem de Células Sanguíneas/normas , Contagem de Eritrócitos , Feminino , Alemanha , Hematócrito , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Valores de Referência , Caracteres Sexuais , Adulto Jovem
19.
BMC Bioinformatics ; 11: 172, 2010 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-20374616

RESUMO

BACKGROUND: Ever since the ground-breaking work of Anfinsen et al. in which a denatured protein was found to refold to its native state, it has been frequently stated by the protein fold prediction community that all the information required for protein folding lies in the amino acid sequence. Recent in vitro experiments and in silico computational studies, however, have shown that cotranslation may affect the folding pathway of some proteins, especially those of ancient folds. In this paper aspects of cotranslational folding have been incorporated into a protein structure prediction algorithm by adapting the Rosetta program to fold proteins as the nascent chain elongates. This makes it possible to conduct a pairwise comparison of folding accuracy, by comparing folds created sequentially from each end of the protein. RESULTS: A single main result emerged: in 94% of proteins analyzed, following the sense of translation, from N-terminus to C-terminus, produced better predictions than following the reverse sense of translation, from the C-terminus to N-terminus. Two secondary results emerged. First, this superiority of N-terminus to C-terminus folding was more marked for proteins showing stronger evidence of cotranslation and second, an algorithm following the sense of translation produced predictions comparable to, and occasionally better than, Rosetta. CONCLUSIONS: There is a directionality effect in protein fold prediction. At present, prediction methods appear to be too noisy to take advantage of this effect; as techniques refine, it may be possible to draw benefit from a sequential approach to protein fold prediction.


Assuntos
Algoritmos , Dobramento de Proteína , Proteínas/química , Bases de Dados de Proteínas , Modelos Moleculares , Reconhecimento Automatizado de Padrão , Conformação Proteica
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