11,701 research outputs found
Accelerating electric vehicle uptake: Modelling public policy options on prices and infrastructure
Transitioning to passenger battery electric vehicles (BEV) can mitigate climate change impacts of road transportation. We develop a novel BEV policy model, nesting it within a national-scale macroeconomic system dynamics model (iSDG-Australia) to simulate a suite of policy pathways. We model combinations of infrastructure support and subsidies, which bring forward the price-parity tipping point, thus rapidly accelerating BEVs’ share of new car sales. However, ongoing complementary charging infrastructure investment is critical to reach 100% new BEV car sales by 2050 in Australia. Even with a rapid transition, the modelled fleet would not achieve net-zero greenhouse gas emissions by 2050 due to vehicle longevity; and suddenly ceasing financial incentives could retard BEV sales by a decade. Based on our assumptions, results suggest emissions reductions are maximised by the fastest transition of the passenger vehicle fleet to BEVs, entailing government policy support from 2020 to 2050, for both adequate infrastructure deployment (AUD17.9b) and vehicle rebates (AUD19.5b), which achieves earlier BEV price-parity with fossil-fuelled vehicles
Systolic blood pressure of Nigerian children with sickle cell disease
Background: Blood pressure readings of adult Nigerians with sickle cell disease (SCD) are reported to be lower than that of the general population but similar studies in children are unavailable.Objectives: To determine the systolic blood pressure (SBP) of children with SCD and compare it with that of healthy controls. Also, to correlate the SBP of children with SCD with age, gender, height and weight.Methods: Children with SCD were recruited from the Paediatric Haematology Clinic of the Lagos University Teaching Hospital. Data collected included bio-demographic details, social classification, height and weight measurements and present clinical status. SBP was measured using a Doppler (VASCUTRACK 120®) and a mercury sphygmomanometer. Similar data were obtained from age and sex matched apparently healthy children.Results: One hundred and twenty three children with SCD and 62 apparently healthy controls were studied; 62% were females. The mean age of the children with SCD was 8.93±3.91years (range 1-17years) and was similar to the controls. SBP was similar in both groups of children (90.9±12.7 versus 92.2±15.2 mmHg; p=0.53) and increased with age. In 91 (74%) children with SCD the SBP was below the 50th centile for the general population. Multiple linear regressions involving sex, age, height and weight found no independent factor to be a significant predictor of the SBP in children with SCD.Conclusion: The SBP of children with SCD is similar to that of age and sex-matched controls. The sex, age, weight and height did not significantly predict SBP in multiple linear regression
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Cross-modal extinction in a boy with severely autistic behaviour and high verbal intelligence
Anecdotal reports from individuals with autism suggest a loss of awareness to stimuli from one modality in the presence of stimuli from another. Here we document such a case in a detailed study of T.M., a 13-year-old boy with autism in whom significant autistic behaviors are combined with an uneven IQ profile of superior verbal and low performance abilities. Although T.M.'s speech is often unintelligible and his behavior is dominated by motor stereotypies and impulsivity, he can communicate by typing or pointing independently within a letter board. A series of experiments using simple and highly salient visual, auditory, and tactile stimuli demonstrated a hierarchy of cross-modal extinction, in which auditory information extinguished other modalities at various levels of processing. T.M. also showed deficits in shifting and sustaining attention. These results provide evidence for mono-channel perception in autism and suggest a general pattern of winner-takes-all processing in which a stronger stimulus-d riven representation dominates behavior, extinguishing weaker representations
Expanding the Genetic Spectrum of ANOS1 Mutations in Patients with Congenital Hypogonadotropic Hypogonadism
STUDY QUESTION:
What is the prevalence and functional consequence of ANOS1 (KAL1) mutations in a group of men with congenital hypogonadotropic hypogonadism (CHH)?
SUMMARY ANSWER:
Three of forty-two (7.1%) patients presented ANOS1 mutations, including a novel splice site mutation leading to exon skipping and a novel contiguous gene deletion associated with ichthyosis.
WHAT IS KNOWN ALREADY:
CHH is characterized by lack of pubertal development and infertility, due to deficient production, secretion or action of GnRH, and can be associated with anosmia/hyposmia (Kallmann syndrome, KS) or with a normal sense of smell (normosmic CHH). Mutations in the anosmin-1 (ANOS1) gene are responsible for the X-linked recessive form of KS.
STUDY DESIGN, SIZE, DURATION:
This cross-sectional study included 42 unrelated men with CHH (20 with KS and 22 with normosmic CHH).
PARTICIPANTS/MATERIALS, SETTING, METHODS:
Patients were screened for mutations in the ANOS1 gene by DNA sequencing. Identified mutations were further investigated by RT-PCR analysis and multiplex ligation-dependent probe amplification (MLPA) analysis.
MAIN RESULTS AND THE ROLE OF CHANCE:
Hemizygous mutations were identified in three (7.1%) KS cases: a novel splice acceptor site mutation (c.542-1G>C), leading to skipping of exon 5 in the ANOS1 transcript in a patient with self-reported normosmia (but hyposmic upon testing); a recurrent nonsense mutation (c.571C>T, p.Arg191*); and a novel 4.8 Mb deletion involving ANOS1 and eight other genes (VCX3B, VCX2, PNPLA4, VCX, STS, HDHD1, VCX3A and NLGN4X) in KS associated with ichthyosis.
LIMITATIONS, REASONS FOR CAUTION:
Objective olfactory testing was not performed in all cases of self-reported normosmia and this may have underestimated the olfactory deficits.
WIDER IMPLICATIONS OF THE FINDINGS:
This study further expands the spectrum of known genetic defects associated with CHH and suggests that patients with self-reported normal olfactory function should not be excluded from ANOS1 genetic testing.
STUDY FUNDING/COMPETING INTEREST(S):
This study was funded by the Portuguese Foundation for Science and Technology. The authors have no conflicts of interest.info:eu-repo/semantics/publishedVersio
Expanding the Genetic Spectrum of ANOS1 Mutations in Patients with Congenital Hypogonadotropic Hypogonadism
STUDY QUESTION:
What is the prevalence and functional consequence of ANOS1 (KAL1) mutations in a group of men with congenital hypogonadotropic hypogonadism (CHH)?
SUMMARY ANSWER:
Three of forty-two (7.1%) patients presented ANOS1 mutations, including a novel splice site mutation leading to exon skipping and a novel contiguous gene deletion associated with ichthyosis.
WHAT IS KNOWN ALREADY:
CHH is characterized by lack of pubertal development and infertility, due to deficient production, secretion or action of GnRH, and can be associated with anosmia/hyposmia (Kallmann syndrome, KS) or with a normal sense of smell (normosmic CHH). Mutations in the anosmin-1 (ANOS1) gene are responsible for the X-linked recessive form of KS.
STUDY DESIGN, SIZE, DURATION:
This cross-sectional study included 42 unrelated men with CHH (20 with KS and 22 with normosmic CHH).
PARTICIPANTS/MATERIALS, SETTING, METHODS:
Patients were screened for mutations in the ANOS1 gene by DNA sequencing. Identified mutations were further investigated by RT-PCR analysis and multiplex ligation-dependent probe amplification (MLPA) analysis.
MAIN RESULTS AND THE ROLE OF CHANCE:
Hemizygous mutations were identified in three (7.1%) KS cases: a novel splice acceptor site mutation (c.542-1G>C), leading to skipping of exon 5 in the ANOS1 transcript in a patient with self-reported normosmia (but hyposmic upon testing); a recurrent nonsense mutation (c.571C>T, p.Arg191*); and a novel 4.8 Mb deletion involving ANOS1 and eight other genes (VCX3B, VCX2, PNPLA4, VCX, STS, HDHD1, VCX3A and NLGN4X) in KS associated with ichthyosis.
LIMITATIONS, REASONS FOR CAUTION:
Objective olfactory testing was not performed in all cases of self-reported normosmia and this may have underestimated the olfactory deficits.
WIDER IMPLICATIONS OF THE FINDINGS:
This study further expands the spectrum of known genetic defects associated with CHH and suggests that patients with self-reported normal olfactory function should not be excluded from ANOS1 genetic testing.
STUDY FUNDING/COMPETING INTEREST(S):
This study was funded by the Portuguese Foundation for Science and Technology. The authors have no conflicts of interest.info:eu-repo/semantics/publishedVersio
Deletion within the Src homology domain 3 of Bruton's tyrosine kinase resulting in X-linked agammaglobulinemia (XLA).
The gene responsible for X-linked agammaglobulinemia (XLA) has been recently identified to code for a cytoplasmic tyrosine kinase (Bruton's agammaglobulinemia tyrosine kinase, BTK), required for normal B cell development. BTK, like many other cytoplasmic tyrosine kinases, contains Src homology domains (SH2 and SH3), and catalytic kinase domain. SH3 domains are important for the targeting of signaling molecules to specific subcellular locations. We have identified a family with XLA whose affected members have a point mutation (g-->a) at the 5' splice site of intron 8, resulting in the skipping of coding exon 8 and loss of 21 amino acids forming the COOH-terminal portion of the BTK SH3 domain. The study of three generations within this kinship, using restriction fragment length polymorphism and DNA analysis, allowed identification of the mutant X chromosome responsible for XLA and the carrier status in this family. BTK mRNA was present in normal amounts in Epstein-Barr virus-induced B lymphoblastoid cell lines established from affected family members. Although the SH3 deletion did not alter BTK protein stability and kinase activity of the truncated BTK protein was normal, the affected patients nevertheless have a severe B cell defect characteristic for XLA. The mutant protein was modeled using the normal BTK SH3 domain. The deletion results in loss of two COOH-terminal beta strands containing several residues critical for the formation of the putative SH3 ligand-binding pocket. We predict that, as a result, one or more crucial SH3 binding proteins fail to interact with BTK, interrupting the cytoplasmic signal transduction process required for B cell differentiation
Motives for a Multidirectional Conditional Spectrum in Seismic Design and Assessment
While the seismic design of structures has traditionally been carried out considering two perpendicular
horizontal components of ground shaking, real ground motions are complex and can impose very different
demands at different orientations of the building with respect to the seismic source. The relevance of this
complexity and its influence on the seismic performance of different kinds of structures has, thus, been receiving
increasing attention in recent years. The authors of this paper have recently focused their research efforts in
studying ways to provide an encompassing definition of seismic demands that aims at designing engineering
structures whose relative performance does not depend on their sensitivity to the angle of incidence of ground
motion. The multidirectional conditional spectrum resulted from this framework and has been recently proposed
by the authors as a tool to characterise seismic demands at different angles of incidence. This paper focuses on
explaining the motives and need for such a tool, and describes in detail the three main components needed for its
generation. Examples are given and the relevance of accounting for the correlation between demands at different
angles is illustrated. Applications and future developments are finally discussed
Is the biology of breast cancer changing? A study of hormone receptor status 1984-1986 and 1996-1997
Using archived tumours, those from 1984-1986 and 1996-1997 underwent immunohistochemistry for hormone receptors and grade analysis. A significant shift towards more ER-positive and low-grade disease was found; this appears to reflect screening practices, but could still influence survival
Anomalous insulator metal transition in boron nitride-graphene hybrid atomic layers
The study of two-dimensional (2D) electronic systems is of great fundamental
significance in physics. Atomic layers containing hybridized domains of
graphene and hexagonal boron nitride (h-BNC) constitute a new kind of
disordered 2D electronic system. Magneto-electric transport measurements
performed at low temperature in vapor phase synthesized h-BNC atomic layers
show a clear and anomalous transition from an insulating to a metallic behavior
upon cooling. The observed insulator to metal transition can be modulated by
electron and hole doping and by the application of an external magnetic field.
These results supported by ab-initio calculations suggest that this transition
in h-BNC has distinctly different characteristics when compared to other 2D
electron systems and is the result of the coexistence between two distinct
mechanisms, namely, percolation through metallic graphene networks and hopping
conduction between edge states on randomly distributed insulating h-BN domains.Comment: 9 pages, 15 figure
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