308 research outputs found
Connectionist perspectives on language learning, representation and processing.
The field of formal linguistics was founded on the premise that language is mentally represented as a deterministic symbolic grammar. While this approach has captured many important characteristics of the world\u27s languages, it has also led to a tendency to focus theoretical questions on the correct formalization of grammatical rules while also de-emphasizing the role of learning and statistics in language development and processing. In this review we present a different approach to language research that has emerged from the parallel distributed processing or \u27connectionist\u27 enterprise. In the connectionist framework, mental operations are studied by simulating learning and processing within networks of artificial neurons. With that in mind, we discuss recent progress in connectionist models of auditory word recognition, reading, morphology, and syntactic processing. We argue that connectionist models can capture many important characteristics of how language is learned, represented, and processed, as well as providing new insights about the source of these behavioral patterns. Just as importantly, the networks naturally capture irregular (non-rule-like) patterns that are common within languages, something that has been difficult to reconcile with rule-based accounts of language without positing separate mechanisms for rules and exceptions
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Limitations for health research with restricted data collection from UK primary care
Purpose
UK primary care provides a rich data source for research. The impact of proposed data collection restrictions is unknown. This study aimed to assess the impact of restricting the scope of electronic health record (EHR) data collection on the ability to conduct research. The study estimated the consequences of restricted data collection on published Clinical Practice Research Datalink studies from high impact journals or referenced in clinical guidelines.
Methods
A structured form was used to systematically analyse the extent to which individual studies would have been possible using a database with data collection restrictions in place: (1) retrospective collection of specified diseases only; (2) retrospective collection restricted to a 6ā or 12āyear period; (3) prospective and retrospective collection restricted to nonāsensitive data. Outcomes were categorised as unfeasible (not reproducible without major bias); compromised (feasible with design modification); or unaffected.
Results
Overall, 91% studies were compromised with all restrictions in place; 56% studies were unfeasible even with design modification. With restrictions on diseases alone, 74% studies were compromised; 51% were unfeasible. Restricting collection to 6/12 years had a major impact, with 67 and 22% of studies compromised, respectively. Restricting collection of sensitive data had a lesser but marked impact with 10% studies compromised.
Conclusion
EHR data collection restrictions can profoundly reduce the capacity for public health research that underpins evidenceābased medicine and clinical guidance. National initiatives seeking to collect EHRs should consider the implications of restricting data collection on the ability to address vital public health questions
Electrochemiluminescence platform for the detection of C-reactive proteins: application of recombinant antibody technology to cardiac biomarker detection
How to Integrate HIV and Sexual and Reproductive Health Services in Namibia, the Epako Clinic Case Study
Introduction: During the past two decades, HIV and Sexual and Reproductive Health services in Namibia have been provided in silos, with high fragmentation. As a consequence of this, quality and efficiency of services in Primary Health Care has been compromised.Ā Methods: We conducted an operational research (observational pre-post study) in a public health facility in Namibia. A health facility assessment was conducted before and after the integration of health services. A person-centred integrated model was implemented to integrate all health services provided at the health facility in addition to HIV and Sexual and Reproductive Health services. Comprehensive services are provided by each health worker to the same patients over time (longitudinality), on a daily basis (accessibility) and with a good external referral system (coordination). Prevalence rates of time flows and productivity were done.Ā Results: Integrated services improved accessibility, stigma and quality of antenatal care services by improving the provider-patient communication, reducing the time that patients stay in the clinic in 16% and reducing the waiting times in 14%. In addition, nurse productivity improved 85% and the expected time in the health facility was reduced 24% without compromising the uptake of TB, HIV, outpatient, antenatal care or first visit family planning services. Given the success on many indicators resulting from integration of services, the goal of this paper was to describe āhowā health services have been integrated, the āprocessā followed and presenting some āresultsā from the integrated clinic.Ā Conclusions: Our study shows that HIV and SRH services can be effectively integrated by following the person-centred integrated model. Based on the Namibian experience on āhowā to integrate health services and the āprocessā to achieve it, other African countries can replicate the model to move away from the silo approach and contribute to the achievement of Universal Health Coverage
Thermal refugia and the survival of species in changing environments: new evidence from a nationally extinct freshwater fish
Variation in global climate during the Quaternary has helped shape current species distributions. The stenohaline fish fauna of the British Isles is generally thought to have colonised eastern England via a landbridge following the last glacial maximum. This theory is investigated using the nationally extinct burbot, Lota lota, as a model species. Samples were collected from 15 museum specimens of known English provenance and analysed for differences in the mitochondrial DNA control region. The DNA analysis produced eight sequences of 270 base pairs, with one sample reaching 420 base pairs in length. Genetic analysis suggests the extinct English population of the burbot was a distinct lineage, differing from those previously described from across the speciesā global distribution. Despite this, network analysis suggests that the English lineage is closely related to populations in western Europe, supporting colonisation via a postglacial landbridge. The rate of genetic divergence suggests that the timing of L. lota's colonisation of English rivers was prior to the last glacial maximum. Lota lota appears to have survived the last glacial maximum in refugia within the British Isles. This study adds to the evidence for a British freshwater refugia and furthers our understanding of the colonisation history of British freshwater fishes. These results also provide valuable information for conservation strategies for L. lota indicating the western European clade as most genetically appropriate for potential future reintroductions to English rivers
Sociodemographic and psychological determinants of influenza vaccine intention among recipients of autologous and allogeneic haematopoietic stem cell transplant: a cross-sectional survey of UK transplant recipients using a modified health belief model
Objectives: Studies exploring vaccination rates among
haematopoietic stem cell transplant (HSCT) recipients
have focused on physician factors that limit uptake.
Understanding the patient factors that determine
vaccination intention is crucial to delivering a successful
vaccination programme. Using a modified health belief
model (mHBM), we conducted a cross-sectional survey
with the objective of exploring the sociodemographic
and psychological factors that determined autologous
and allogeneic HSCT recipientsā intention to receive the
seasonal inactivated influenza vaccine (SIIV) during the
2015ā2016 influenza season.
Setting: The setting of our study was three tertiary
level, UK National Health Service (NHS) autologous and
allogeneic HSCT centres.
Participants: Eligible patients were aged 16 years or
over and recipients of autologous or allogeneic HSCT for
any disease indication, with no absolute contraindication
to receiving the SIIV during the next influenza season,
and having not received the SIIV since transplant. 93
participants from 3 UK NHS HSCT centres completed an
anonymous study-specific questionnaire. 78.5% were
recipients of allogeneic and 21.5% autologous HSCT.
Results: 23.7% of participants expressed low intent to
receive the SIIV. Patients aged over 65 (OR 0.02, 95%CI
0.01 to 0.57, p=0.02) and those who had not received the
SIIV prior to HSCT (OR 0.04, 95% CI 0.02 to 0.56, p=0.02)
were less likely to have high intent. A multivariate logistic
regression model incorporating constructs of the mHBM
was statistically significant (p<0.001) and explained
74.7% of variation in SIIV intention. More patients felt
that a recommendation from their HSCT team than their
general practitioner would prompt them to receive the
SIIV, and this was most pronounced in those who had low
intent.
Conclusions: The mHBM may provide a useful structure
for addressing low vaccine intent among HSCT recipients
and further interventional studies are warranted. We would
encourage HSCT and general practitioners to discuss SIIV
intention as a routine part of care
The effect of pre-pregnancy body mass index on breastfeeding initiation, intention and duration:A systematic review and dose-response meta-analysis
Overweight and obesity not only are major risk factors for number of chronic diseases, but also a risk factor for pregnancy complications in women. The present study aims to investigate the association between pre-pregnancy BMI and the persistence and duration of BF. The electronic databases including Medline (PubMed), Scopus, Embase, Web of Science and Google Scholar were searched for papers with titles and/or abstracts including one of our keywords and published up to 15 April 2019. For dose-response relationship, the two-stage random-effects meta-analysis was performed using the Ć¢ļæ½ļæ½dosresmetaĆ¢ļæ½ļæ½ function in R software. Thirty-two studies with the effect of pre-pregnancy BMI on BF initiation, intention and duration were included in the present study. Based on crude and adjusted OR models, the risk of BF cessation increased by 4 (OR = 1.04; 95 CI: 1.02Ć¢ļæ½ļæ½1.05) with an increase in a unit of BMI. In addition, based on crude and adjusted RR models, the risk of BF cessation increases by 2 and 1 (crude RR = 1.02; 95 CI: 1.01Ć¢ļæ½ļæ½1.03 and adjusted RR = 1.01; 95 CI: 0.99Ć¢ļæ½ļæ½1.02) with an increase in one unit of BMI. Based on the result, the health care professionals and other key stakeholders should be aware of the impact excess weight, and that women who are overweight or obese should be encouraged with continued access to guidance, counseling and support, starting from conception, to maximize BF outcomes. ĆĀ© 2020 The Authors Public health; Women's health; Reproductive medicine; Obstetrics and gynecology; Reproductive system; Clinical research; Pre-pregnancy, Body mass index, Breastfeeding, Initiation, Duration. ĆĀ© 2020 The Author
Functional Analysis of Human Hematopoietic Stem Cell Gene Expression Using Zebrafish
Although several reports have characterized the hematopoietic stem cell (HSC) transcriptome, the roles of HSC-specific genes in hematopoiesis remain elusive. To identify candidate regulators of HSC fate decisions, we compared the transcriptome of human umbilical cord blood and bone marrow CD34(+)CD33(ā)CD38(ā)Rho(lo)c-kit(+) cells, enriched for hematopoietic stem/progenitor cells with CD34(+)CD33(ā)CD38(ā)Rho(hi) cells, enriched in committed progenitors. We identified 277 differentially expressed transcripts conserved in these ontogenically distinct cell sources. We next performed a morpholino antisense oligonucleotide (MO)-based functional screen in zebrafish to determine the hematopoietic function of 61 genes that had no previously known function in HSC biology and for which a likely zebrafish ortholog could be identified. MO knock down of 14/61 (23%) of the differentially expressed transcripts resulted in hematopoietic defects in developing zebrafish embryos, as demonstrated by altered levels of circulating blood cells at 30 and 48 h postfertilization and subsequently confirmed by quantitative RT-PCR for erythroid-specific hbae1 and myeloid-specific lcp1 transcripts. Recapitulating the knockdown phenotype using a second MO of independent sequence, absence of the phenotype using a mismatched MO sequence, and rescue of the phenotype by cDNA-based overexpression of the targeted transcript for zebrafish spry4 confirmed the specificity of MO targeting in this system. Further characterization of the spry4-deficient zebrafish embryos demonstrated that hematopoietic defects were not due to more widespread defects in the mesodermal development, and therefore represented primary defects in HSC specification, proliferation, and/or differentiation. Overall, this high-throughput screen for the functional validation of differentially expressed genes using a zebrafish model of hematopoiesis represents a major step toward obtaining meaningful information from global gene profiling of HSCs
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