393 research outputs found
Self‐assembled quantum dots of InSb grown on InP by atomic layer molecular beam epitaxy: Morphology and strain relaxation
Self-organized InSb dots grown by atomic layer molecular beam epitaxy on InP substrates have
been characterized by atomic force and transmission electron microscopy. Measurement of
high-energy electron diffraction during the growth indicates a Stransky–Krastanov growth mode
beyond the onset of 1.4 InSb monolayer ~ML! deposition. The dots obtained after a total deposition
of 5 and 7 ML of InSb present a truncated pyramidal morphology with rectangular base oriented
along the ^110& directions, elongated towards the @110# direction with 113%/111%A lateral facets in @11
¯
0# views, and ~001! flat top surfaces. The mismatch between
the dot and the substrate has been accommodated by a network of 90° misfit dislocation at the
interface. A corrugation of the InP substrate surrounding the dot has been also observedThis work has been funded by the Spanish CICYT
Project MAT95-0966.Peer reviewe
Metal–organic fireworks: MOFs as integrated structural scaffolds for pyrotechnic materials
A new approach to formulating pyrotechnic materials is presented whereby constituent ingredients are bound together in a solid-state lattice. This reduces the batch inconsistencies arising from the traditional approach of combining powders by ensuring the key ingredients are ‘mixed’ in appropriate quantities and are in intimate contact. Further benefits of these types of material are increased safety levels as well as simpler logistics, storage and manufacture. A systematic series of new frameworks comprising fuel and oxidiser agents (group 1 and 2 metal nodes & terephthalic acid derivatives as linkers) has been synthesised and structurally characterised. These new materials have been assessed for pyrotechnic effect by calorimetry and burn tests. Results indicate that these materials exhibit the desired pyrotechnic material properties and the effect can be correlated to the dimensionality of the structure. A new approach to formulating pyrotechnic materials is proposed whereby constituent ingredients are bound together in a solid-state lattice. A series of Metal–organic framework frameworks comprising fuel and oxidiser agents exhibits the desired properties of a pyrotechnic material and this effect is correlated to the dimensionality of the structure
The systemic lupus erythematosus IRF5 risk haplotype is associated with systemic sclerosis
Systemic sclerosis (SSc) is a fibrotic autoimmune disease in which the genetic component plays an important role. One of the strongest SSc association signals outside the human leukocyte antigen (HLA) region corresponds to interferon (IFN) regulatory factor 5 (IRF5), a major regulator of the type I IFN pathway. In this study we aimed to evaluate whether three different haplotypic blocks within this locus, which have been shown to alter the protein function influencing systemic lupus erythematosus (SLE) susceptibility, are involved in SSc susceptibility and clinical phenotypes. For that purpose, we genotyped one representative single-nucleotide polymorphism (SNP) of each block (rs10488631, rs2004640, and rs4728142) in a total of 3,361 SSc patients and 4,012 unaffected controls of Caucasian origin from Spain, Germany, The Netherlands, Italy and United Kingdom. A meta-analysis of the allele frequencies was performed to analyse the overall effect of these IRF5 genetic variants on SSc. Allelic combination and dependency tests were also carried out. The three SNPs showed strong associations with the global disease (rs4728142: P = 1.34×10<sup>−8</sup>, OR = 1.22, CI 95% = 1.14–1.30; rs2004640: P = 4.60×10<sup>−7</sup>, OR = 0.84, CI 95% = 0.78–0.90; rs10488631: P = 7.53×10<sup>−20</sup>, OR = 1.63, CI 95% = 1.47–1.81). However, the association of rs2004640 with SSc was not independent of rs4728142 (conditioned P = 0.598). The haplotype containing the risk alleles (rs4728142*A-rs2004640*T-rs10488631*C: P = 9.04×10<sup>−22</sup>, OR = 1.75, CI 95% = 1.56–1.97) better explained the observed association (likelihood P-value = 1.48×10<sup>−4</sup>), suggesting an additive effect of the three haplotypic blocks. No statistical significance was observed in the comparisons amongst SSc patients with and without the main clinical characteristics. Our data clearly indicate that the SLE risk haplotype also influences SSc predisposition, and that this association is not sub-phenotype-specific
Usefulness of bone turnover markers as predictors of mortality risk, disease progression and skeletal-related events appearance in patients with prostate cancer with bone metastases following treatment with zoledronic acid: TUGAMO study
Owing to the limited validity of clinical data on the treatment of prostate cancer (PCa) and bone metastases,
biochemical markers are a promising tool for predicting survival, disease progression and skeletal-related events (SREs) in these
patients. The aim of this study was to evaluate the predictive capacity of biochemical markers of bone turnover for mortality risk,
disease progression and SREs in patients with PCa and bone metastases undergoing treatment with zoledronic acid (ZA).
Methods: This was an observational, prospective and multicenter study in which ninety-eight patients were included. Patients
were treated with ZA (4mg every 4 weeks for 18 months). Data were collected at baseline and 3, 6, 9, 12, 15 and 18 months after
the beginning of treatment. Serum levels of bone alkaline phosphtase (BALP), aminoterminal propeptide of procollagen type I
(P1NP) and beta-isomer of carboxiterminal telopeptide of collagen I (b-CTX) were analysed at all points in the study. Data on
disease progression, SREs development and survival were recorded.
Results: Cox regression models with clinical data and bone markers showed that the levels of the three markers studied were
predictive of survival time, with b-CTX being especially powerful, in which a lack of normalisation in visit 1 (3 months after the
beginning of treatment) showed a 6.3-times more risk for death than in normalised patients. Levels of these markers were also
predictive for SREs, although in this case BALP and P1NP proved to be better predictors. We did not find any relationship
between bone markers and disease progression.
Conclusion: In patients with PCa and bone metastases treated with ZA, b-CTX and P1NP can be considered suitable predictors for
mortality risk, while BALP and P1NP are appropriate for SREs. The levels of these biomarkers 3 months after the beginning of
treatment are especially importantThis study was supported by Novartis Oncology Spai
Meta-Reflection on an Applied Hermeneutic Phenomenology: Methodological Challenges of a Study on Young-Women's Political Participation
In this article, we present a meta-reflection on the following questions: What methodological challenges arise when using VAN MANEN's (1990, 2014) applied hermeneutic phenomenology in a study of young-women's political participation? How can its analysis contribute to a critical reflection on this methodology in the human sciences? We present methodological challenges regarding delimiting the phenomenon, defining the research question, selecting participants, collecting data, conducting thematic analysis and working with a diverse team. We conclude that these challenges are transferable to other empirical phenomenological research, and that researcher reflexivity is key to facing them.In diesem Artikel präsentieren wir eine Meta-Reflexion zu folgenden Fragen: Welche methodologischen Herausforderungen ergeben sich bei der Anwendung von VAN MANENs (1990, 2014) angewandter hermeneutischer Phänomenologie in einer Studie über die politische Beteiligung junger Frauen? Wie kann ihre Analyse zu einer kritischen Reflexion über diese Methodologie in den Humanwissenschaften beitragen? Wir stellen die methodologischen Herausforderungen in Bezug auf die Abgrenzung des Phänomens, die Definition der Forschungsfrage, die Auswahl der Teilnehmer*innen, die Datenerhebung, die Durchführung der thematischen Analyse und die Arbeit mit einem Forschungsteam dar. Wir kommen zu dem Schluss, dass diese Herausforderungen auf andere empirische phänomenologische Forschung übertragbar sind und dass die Reflexivität der Forschenden der Schlüssel zu ihrer Bewältigung ist
Biochemical markers of bone turnover and clinical outcome in patients with renal cell and bladder carcinoma with bone metastases following treatment with zoledronic acid: The TUGAMO study
Background: Levels of bone turnover markers (BTM) might be correlated with outcome in terms of skeletal-related events (SRE),
disease progression, and death in patients with bladder cancer (BC) and renal cell carcinoma (RCC) with bone metastases (BM).
We try to evaluate this possible correlation in patients who receive treatment with zoledronic acid (ZOL).
Methods: This observational, prospective, and multicenter study analysed BTM and clinical outcome in these patients. Serum
levels of bone alkaline phosphatase (BALP), procollagen type I amino-terminal propeptide (PINP), and beta-isomer of carboxyterminal
telopeptide of type I collagen (b-CTX) were analysed.
Results: Patients with RCC who died or progressed had higher baseline b-CTX levels and those who experienced SRE during
follow-up showed high baseline BALP levels. In BC, a poor rate of survival was related with high baseline b-CTX and BALP levels,
and new SRE with increased PINP levels. Cox univariate analysis showed that b-CTX levels were associated with higher mortality
and disease progression in RCC and higher mortality in BC. Bone alkaline phosphatase was associated with increased risk of
premature SRE appearance in RCC and death in BC.
Conclusion: Beta-isomer of carboxy-terminal telopeptide of type I collagen and BALP can be considered a complementary tool
for prediction of clinical outcomes in patients with BC and RCC with BM treated with ZOLNovartis Oncology Spain for supporting this stud
The RESPITE trial: remifentanil intravenously administered patient-controlled analgesia (PCA) versus pethidine intramuscular injection for pain relief in labour: study protocol for a randomised controlled trial
Background
The commonest opioid used for pain relief in labour is pethidine (meperidine); however, its effectiveness has long been challenged and the drug has known side effects including maternal sedation, nausea and potential transfer across the placenta to the foetus. Over a third of women receiving pethidine require an epidural due to inadequate pain relief. Epidural analgesia increases the risk of an instrumental vaginal delivery and its associated effects. Therefore, there is a clear need for a safe, effective, alternative analgesic to pethidine. Evidence suggests that remifentanil patient-controlled analgesia (PCA) reduces epidural conversion rates compared to pethidine; however, no trial has yet investigated this as a primary endpoint. We are, therefore, comparing pethidine intramuscular injection to remifentanil PCA in a randomised controlled trial.
Methods/design
Women in established labour, requesting systemic opioid pain relief, will be randomised to either intravenously administered remifentanil PCA (intervention) or pethidine intramuscular injection (control) in an unblinded, 1:1 individual randomised trial.
Following informed consent, 400 women in established labour, who request systemic opioid pain relief, from NHS Trusts across England will undergo a minimised randomisation by a computer or automated telephone system to either pethidine or remifentanil. In order to balance the groups this minimisation is based on four parameters; parity (nulliparous versus multiparous), maternal age (<20, 20 < 30, 30 < 40, 40+ years), ethnicity (South Asian (Pakistani/Indian/Bangladeshi) versus Other) and induced versus spontaneous labour.
The effectiveness of pain relief provided by each technique will be recorded every 30 min after time zero, until epidural placement, delivery or transfer to theatre, quantified by Visual Analogue Scale. Incidence of maternal side effects including sedation, delivery mode, foetal distress requiring delivery, neonatal status at delivery and rate of initiation of breastfeeding within the first hour of birth will also be recorded.
Maternal satisfaction with her childbirth experience will be determined by a postpartum questionnaire prior to discharge from the delivery ward.
Discussion
The RESPITE trial’s primary outcome is the proportion of women who have an epidural placed for pain relief in labour in each arm.
Trial Registration
Current Controlled Trials registration number: ISRCTN29654603. Registered on 23 July 2013
Megabank found? Flanks record sea level
On Leg 101, the first international voyage for the Ocean Drilling Program, the deep-sea drilling ship JOIOES Resolution (SEDCO/BP 471) left Miami, Fla., on Jan. 31 to investigate the geology of the Bahamas. (Leg 100 tested the Resolution's readiness. See July Geotimes.) Before returning to Miami on March 14, the crew had drilled 19 holes al 11 sites and recovered 46.2% of the cored section (about 1.5 of 3.1 km cored). The scientific party wanted to test conflicting hypotheses about the development of the modern shallow water carbonate banks and intervening deep -water throughs in the Bahamas, and to study the growth patterns of carbonate slopes and their response to sea-level fluctuations. Those objectives (the 'deep ' and the 'shallow') were selected beause recent advances in interpreting the micropaleontology of shallow-water carbonate platforms, coupled with data from previous sedimentological investigations and regional and site-specific seismic surveys, now permit consistent stratigraphic comparisons in the Bahamas
Efectos adversos neuropsiquiátricos de dolutegravir en la práctica clínica real
Introducción
Los inhibidores de la integrasa, y especialmente dolutegravir (DTG), son el tratamiento de primera línea antirretroviral por su eficacia y seguridad. Aunque en los ensayos pivotales la tasa de efectos adversos (EA) era baja (2-3%), en los estudios de vida real parece ser mayor, especialmente los EA neuropsiquiátricos. El objetivo fue determinar el porcentaje de EA e interrupción de DTG en nuestro centro y la relación con los antecedentes psiquiátricos.
Métodos
Estudio descriptivo retrospectivo de pacientes que iniciaron DTG entre 2015-2017. Se registraron: interrupción del tratamiento, EA y enfermedad psiquiátrica. Se realizó seguimiento desde el inicio del del tratamiento con DTG y se registraron las hospitalizaciones y las visitas a urgencias y atención primaria. Fue autorizado por el Comité Ético de Investigación Clínica de Aragón.
Resultados
Se incluyeron 283 pacientes, entre 11-87 años, 70% varones. El 21% naive. Interrumpieron el tratamiento con DTG el 24%, un 10% por EA. Se detectó un 5% de EA neuropsiquiátricos. Este grupo tenía más antecedentes psiquiátricos (62 vs. 41%; p = 0, 002) que el de pacientes que continuaron el tratamiento, y precisaron más visitas en atención primaria (18, 8 vs. 8, 4%; p = 0, 016) y urgencias (8, 7 vs. 3, 3%; p = 0, 061).
Conclusión
Los pacientes que interrumpieron el tratamiento con DTG tenían más antecedentes psiquiátricos. Por ello, aunque se precisan más estudios, sería necesario valorar este antecedente previamente al tratamiento con inhibidores de la integrasa. Síntomas como ansiedad, insomnio o depresión pueden ser EA de DTG con una frecuencia mayor de la esperada. Ser identificados por los médicos de atención primaria y urgencias podría evitar una cascada de prescripción innecesaria.
Introduction: Integrase inhibitors and especially dolutegravir (DTG) are placed as a first-line antiretroviral treatment for their efficacy and safety. Although in the pivotal trials the rate of adverse effects (AEs) was low (2-3%), in real-life studies it appears to be higher, especially neuropsychiatric AEs. The objective is to determine the percentage of AEs and discontinuation of DTG in our site and the relationship with the psychiatric background.
Methods: Retrospective descriptive study of patients starting DTG from 2015 to 2017. Discontinuation of treatment, AEs and previous psychiatric pathology were recorded. Follow-up is carried out since the beginning of the treatment, and hospitalizations and emergency room and primary care visits were registered. The study was authorized by the Ethics Committee for Clinical Research of Aragon.
Results: Two hundred and eighty-three patients were included, between 11 and 87 years old, 70% male. 21% were naive. 24% of the patients discontinued treatment with DTG, 10% due to AEs. Neuropsychiatric AEs were detected in 5%. This group of patients had a more frequent previous psychiatric history (62 vs. 41%; P =.002) than the ongoing treatment group and they needed more visits to primary care (18.8 vs. 8.4%; P =.016) and emergency room (8, 7 vs. 3.3%; P =.061).
Conclusion: Patients who discontinued treatment with DTG had more psychiatric history. Although more studies are required, it is necessary to assess this background before starting treatment with integrase inhibitors. Symptoms such as anxiety, insomnia or depression can be DTG AEs more frequently than expected. Being identified by primary care and emergency physicians could avoid the unnecessary prescription of other medications
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