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The biological pump supplies carbon to the oceans' interior, driving long-term carbon sequestration and providing energy for deep-sea ecosystems1,2. Its efficiency is set by transformations of newly formed particles in the euphotic zone, followed by vertical flux attenuation via mesopelagic processes3. Depth attenuation of the particulate organic carbon (POC) flux is modulated by multiple processes involving zooplankton and/or microbes4,5. Nevertheless, it continues to be mainly parameterized using an empirically derived relationship, the 'Martin curve'6. The derived power-law exponent is the standard metric used to compare flux attenuation patterns across oceanic provinces7,8. Here we present in situ experimental findings from C-RESPIRE9, a dual particle interceptor and incubator deployed at multiple mesopelagic depths, measuring microbially mediated POC flux attenuation. We find that across six contrasting oceanic regimes, representing a 30-fold range in POC flux, degradation by particle-attached microbes comprised 7-29 per cent of flux attenuation, implying a more influential role for zooplankton in flux attenuation. Microbial remineralization, normalized to POC flux, ranged by 20-fold across sites and depths, with the lowest rates at high POC fluxes. Vertical trends, of up to threefold changes, were linked to strong temperature gradients at low-latitude sites. In contrast, temperature played a lesser role at mid- and high-latitude sites, where vertical trends may be set jointly by particle biochemistry, fragmentation and microbial ecophysiology. This deconstruction of the Martin curve reveals the underpinning mechanisms that drive microbially mediated POC flux attenuation across oceanic provinces.
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To limit global warming below 2°C by 2100, we must drastically reduce greenhouse gas emissions and additionally remove ~100-900 Gt CO2 from the atmosphere (carbon dioxide removal, CDR) to compensate for unavoidable emissions. Seaweeds (marine macroalgae) naturally grow in coastal regions worldwide where they are crucial for primary production and carbon cycling. They are being considered as a biological method for CDR and for use in carbon trading schemes as offsets. To use seaweeds in carbon trading schemes requires verification that seaweed photosynthesis that fixes CO2 into organic carbon results in CDR, along with the safe and secure storage of the carbon removed from the atmosphere for more than 100 years (sequestration). There is much ongoing research into the magnitude of seaweed carbon storage pools (e.g., as living biomass and as particulate and dissolved organic carbon in sediments and the deep ocean), but these pools do not equate to CDR unless the amount of CO2 removed from the atmosphere as a result of seaweed primary production can be quantified and verified. The draw-down of atmospheric CO2 into seawater is via air-sea CO2 equilibrium, which operates on time scales of weeks to years depending upon the ecosystem considered. Here, we explain why quantifying air-sea CO2 equilibrium and linking this process to seaweed carbon storage pools is the critical step needed to verify CDR by discrete seaweed beds and nearshore and open ocean aquaculture systems prior to their use in carbon trading.
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Ecosistema , Algas Marinas , Dióxido de Carbono , Agua de Mar , BiomasaRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Antarctic krill (Euphausia superba) are swarming, oceanic crustaceans, up to two inches long, and best known as prey for whales and penguins - but they have another important role. With their large size, high biomass and daily vertical migrations they transport and transform essential nutrients, stimulate primary productivity and influence the carbon sink. Antarctic krill are also fished by the Southern Ocean's largest fishery. Yet how krill fishing impacts nutrient fertilisation and the carbon sink in the Southern Ocean is poorly understood. Our synthesis shows fishery management should consider the influential biogeochemical role of both adult and larval Antarctic krill.
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Biomasa , Euphausiacea/fisiología , Cadena Alimentaria , Spheniscidae/fisiología , Ballenas/fisiología , Animales , Regiones Antárticas , Carbono/metabolismo , Ciclo del Carbono , Euphausiacea/crecimiento & desarrollo , Agua de Mar/químicaRESUMEN
OBJECTIVES: Literature regarding Montessori-based activities with older adults with dementia is fairly common with early stages of dementia. Conversely, research on said activities with individuals experiencing late-stage dementia is limited because of logistical difficulties in sampling and data collection. Given the need to understand risks and benefits of treatments for individuals with late-stage dementia, specifically regarding their mental and behavioral health, this study sought to evaluate the effects of a Montessori-based activity program implemented in a long-term care facility. METHOD: Utilizing an interrupted time series design, trained staff completed observation-based measures for 43 residents with late-stage dementia at three intervals over six months. Empirical measures assessed mental health (anxiety, psychological well-being, quality of life) and behavioral health (problem behaviors, social engagement, capacity for activities of daily living). RESULTS: Group differences were observed via repeated measures ANOVA and paired-samples t-tests. The aggregate, longitudinal results-from baseline to final data interval-for the psychological and behavioral health measures were as follows: problem behaviors diminished though not significantly; social engagement decreased significantly; capacities for activities of daily living decreased significantly; quality of life increased slightly but not significantly; anxiety decreased slightly but not significantly; and psychological well-being significantly decreased. CONCLUSION: Improvements observed for quality of life and problem behaviors may yield promise for Montessori-based activities and related health care practices. The rapid physiological and cognitive deterioration from late-stage dementia should be considered when interpreting these results.
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Demencia/terapia , Relaciones Interpersonales , Calidad de Vida/psicología , Índice de Severidad de la Enfermedad , Actividades Cotidianas , Anciano , Ansiedad/psicología , Demencia/psicología , Femenino , Humanos , Estudios Longitudinales , Masculino , Casas de Salud , Problema de Conducta/psicologíaRESUMEN
The low-mass X-ray binary 4U1705-44 exhibits dramatic long-term X-ray time variability with a timescale of several hundred days. The All-Sky Monitor (ASM) aboard the Rossi X-ray Timing Explorer (RXTE) and the Japanese Monitor of All-sky X-ray Image (MAXI) aboard the International Space Station together have continuously observed the source from December 1995 through May 2014. The combined ASM-MAXI data provide a continuous time series over fifty times the length of the timescale of interest. Topological analysis can help us identify fingerprints in the phase-space of a system unique to its equations of motion. The Birman-Williams theorem postulates that if such fingerprints are the same between two systems, then their equations of motion must be closely related. The phase-space embedding of the source light curve shows a strong resemblance to the double-welled nonlinear Duffing oscillator. We explore a range of parameters for which the Duffing oscillator closely mirrors the time evolution of 4U1705-44. We extract low period, unstable periodic orbits from the 4U1705-44 and Duffing time series and compare their topological information. The Duffing and 4U1705-44 topological properties are identical, providing strong evidence that they share the same underlying template. This suggests that we can look to the Duffing equation to help guide the development of a physical model to describe the long-term X-ray variability of this and other similarly behaved X-ray binary systems.
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The electrode in a cochlear implant (CI) system is a key factor in hearing performance as it is the interface between the device and the auditory pathway of the recipient. The first CI electrodes were straight and thus adopted a lateral wall position. Subsequent innovations include: perimodiolar electrodes designed to lie adjacent to the modiolar wall and thus to provide more spatially-focused stimulation of the spiral ganglion cells; shorter atraumatic straight electrodes for combined electric and acoustic (hybrid) stimulation. This paper explores the relative merits of straight and perimodiolar electrodes in the search for the optimal electrode design with reference to electrodes from Cochlear(®).
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Implantes Cocleares , Diseño de Prótesis , Humanos , Selección de PacienteRESUMEN
Multipurpose prevention technologies (MPTs) that aim to simultaneously prevent unintended pregnancy, HIV-1 infection and other sexually transmitted infections are among the most innovative and complex products currently in development within women's sexual and reproductive health care. In this review article, MPTs are placed within the wider context of combination products, combination drug products and multi-indication products. The current MPT product landscape is mapped and assessed with reference to existing products for the corresponding single indications, before identifying the gaps in the current MPT product pipeline and highlighting priority products and challenges moving forward.
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Dispositivos Anticonceptivos , Infecciones por VIH/prevención & control , Embarazo no Planeado , Enfermedades de Transmisión Sexual/prevención & control , Combinación de Medicamentos , Femenino , Humanos , Embarazo , Salud Reproductiva , Salud de la MujerRESUMEN
OBJECTIVE: To assess the public health consequences of the rise in multiple births with respect to congenital anomalies. DESIGN: Descriptive epidemiological analysis of data from population-based congenital anomaly registries. SETTING: Fourteen European countries. POPULATION: A total of 5.4 million births 1984-2007, of which 3% were multiple births. METHODS: Cases of congenital anomaly included live births, fetal deaths from 20 weeks of gestation and terminations of pregnancy for fetal anomaly. MAIN OUTCOME MEASURES: Prevalence rates per 10,000 births and relative risk of congenital anomaly in multiple versus singleton births (1984-2007); proportion prenatally diagnosed, proportion by pregnancy outcome (2000-07). Proportion of pairs where both co-twins were cases. RESULTS: Prevalence of congenital anomalies from multiple births increased from 5.9 (1984-87) to 10.7 per 10,000 births (2004-07). Relative risk of nonchromosomal anomaly in multiple births was 1.35 (95% CI 1.31-1.39), increasing over time, and of chromosomal anomalies was 0.72 (95% CI 0.65-0.80), decreasing over time. In 11.4% of affected twin pairs both babies had congenital anomalies (2000-07). The prenatal diagnosis rate was similar for multiple and singleton pregnancies. Cases from multiple pregnancies were less likely to be terminations of pregnancy for fetal anomaly, odds ratio 0.41 (95% CI 0.35-0.48) and more likely to be stillbirths and neonatal deaths. CONCLUSIONS: The increase in babies who are both from a multiple pregnancy and affected by a congenital anomaly has implications for prenatal and postnatal service provision. The contribution of assisted reproductive technologies to the increase in risk needs further research. The deficit of chromosomal anomalies among multiple births has relevance for prenatal risk counselling.
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Anomalías Congénitas/epidemiología , Muerte Fetal/epidemiología , Progenie de Nacimiento Múltiple , Complicaciones del Embarazo/epidemiología , Mortinato/epidemiología , Europa (Continente)/epidemiología , Femenino , Humanos , Embarazo , Resultado del Embarazo , Diagnóstico Prenatal , Prevalencia , Sistema de Registros , RiesgoRESUMEN
OBJECTIVE: To review changes in and impact of prenatal screening and diagnosis. DESIGN: Population-based congenital anomaly register study. SETTING: Oxfordshire. POPULATION: Congenital anomalies confirmed and those suspected prenatally, delivered 1991-2008. METHODS: Analysis of proportions of congenital anomalies confirmed and those suspected prenatally. MAIN OUTCOME MEASURES: Birth prevalence, prenatal detection rates, pregnancy outcomes. RESULTS: A total of 2651 (2.3%) infants/fetuses had a congenital anomaly diagnosed. There were 3839 suspected or confirmed cases, 2847 due to a prenatal suspicion, of which 1659 had an anomaly confirmed at delivery, and 1188 false-positive diagnoses, 91% due to reporting ultrasound normal variants. The percentage of prenatal notifications rose from 48% in 1991-93 to 83-88% from 1996 to 2003 and dropped to 61% in 2006-08, partly reflecting changes in the reporting of normal variants. Reporting these increased the prenatal diagnosis rate from 53 to 63% with an increase in false-positive rate from 0.09 to 1.04%. A total of 722 (44% of prenatally detected affected fetuses) resulted in termination; 48% of these had chromosome anomalies, 34% had isolated structural anomalies, 7% had multiple anomalies, 10% had familial disorders; 42% had lethal anomalies and 58% would probably have survived the neonatal period giving an estimated 20% reduction in birth prevalence of congenital anomalies compatible with survival because of terminations. CONCLUSION: There has been an improvement in prenatal detection of congenital anomalies over the two decades studied. The recognition that reporting normal variants, although increasing prenatal detection rates, leads to an increase in false-positive diagnoses has had an impact on practice that has redressed the balance between these two effects.
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Anomalías Congénitas/diagnóstico por imagen , Feto/anomalías , Diagnóstico Prenatal/tendencias , Ultrasonografía Prenatal/tendencias , Aborto Inducido/estadística & datos numéricos , Femenino , Edad Gestacional , Humanos , Embarazo , Resultado del Embarazo , Diagnóstico Prenatal/normas , Sensibilidad y Especificidad , Ultrasonografía Prenatal/normasRESUMEN
BACKGROUND: Rheumatic heart disease (RHD) remains an important health issue for indigenous women of child-bearing age in northern Australia. However, the influence of RHD on maternal outcomes with current clinical practice is unclear. AIMS: To determine maternal cardiac complications and obstetric outcomes in patients with RHD. METHODS: Retrospective case note analysis of women with RHD who received obstetric care between July 1999 and May 2010 at Cairns Base Hospital in north Queensland. Outcome measures were obstetric interventions and outcomes, cardiac interventions and complications, stratified according to a cardiac risk score (CRS). RESULTS: Ninety-five confinements occurred in 54 patients, of whom 52 were Indigenous Australians. There were no maternal or neonatal deaths. With a CRS of 0, cardiac complications occurred in 0 of 70 confinements; with a CRS of 1, complications occurred in 5 of 17 confinements (29%); with a CRS of >1, complications occurred in 2 of 4 confinements (50%). Another four patients were first diagnosed with RHD after developing acute pulmonary oedema during the peripartum period. CONCLUSIONS: RHD has a major impact on maternal cardiac outcomes. However, with current management practices, maternal and fetal mortality are low, and the incidence of complications is predictable based on known risk factors.
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Complicaciones Cardiovasculares del Embarazo/epidemiología , Cardiopatía Reumática/epidemiología , Adulto , Fármacos Cardiovasculares/uso terapéutico , Parto Obstétrico , Femenino , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/tratamiento farmacológico , Enfermedades de las Válvulas Cardíacas/epidemiología , Humanos , Recién Nacido , Nativos de Hawái y Otras Islas del Pacífico , Paridad , Embarazo , Complicaciones Cardiovasculares del Embarazo/diagnóstico por imagen , Complicaciones Cardiovasculares del Embarazo/tratamiento farmacológico , Resultado del Embarazo , Trastornos Puerperales/epidemiología , Edema Pulmonar/epidemiología , Queensland/epidemiología , Estudios Retrospectivos , Cardiopatía Reumática/diagnóstico por imagen , Cardiopatía Reumática/tratamiento farmacológico , Ultrasonografía , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/tratamiento farmacológico , Disfunción Ventricular Izquierda/epidemiología , Adulto JovenRESUMEN
OBJECTIVES: To investigate whether there is an association between risk of congenital anomaly and annual ward level exposure to air pollution in England during the 1990s. METHODS: A geographical study was conducted across four regions of England using population-based congenital anomaly registers, 1991-1999. Exposure was measured as 1996 annual mean background sulphur dioxide (SO(2)), nitrogen dioxide (NO(2)) and particulate matter (PM(10)) concentrations at census ward level (n=1474). Poisson regression, controlling for maternal age, area socioeconomic deprivation and hospital catchment area, was used to estimate relative risk for an increase in pollution from the 10th to the 90th centile. RESULTS: For non-chromosomal anomalies combined, relative risks were 0.99 (95% CI 0.93 to 1.05) for SO(2), 0.97 (95% CI 0.84 to 1.11) for NO(2) and 0.89 (95% CI 0.75 to 1.07) for PM(10). For chromosomal anomalies, relative risks were 1.06 (95% CI 0.98 to 1.15) for SO(2), 1.11 (95% CI 0.95 to 1.30) for NO(2) and 1.18 (95% CI 0.97 to 1.42) for PM(10). Raised risks were found for tetralogy of Fallot and SO(2) (RR=1.38, 95% CI 1.07 to 1.79), NO(2) (RR=1.44, 95% CI 0.71 to 2.93) and PM(10) (RR=1.48, 95% CI 0.57 to 3.84), which is of interest in light of previously reported associations between this cardiac anomaly and other air pollutants. CONCLUSIONS: While air pollution in the 1990s did not lead to sustained geographical differences in the overall congenital anomaly rate in England, further research regarding specific anomalies is indicated.
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Contaminación del Aire/efectos adversos , Anomalías Congénitas/epidemiología , Exposición Materna/efectos adversos , Dióxido de Nitrógeno/toxicidad , Efectos Tardíos de la Exposición Prenatal/epidemiología , Dióxido de Azufre/toxicidad , Adulto , Contaminación del Aire/análisis , Anomalías Congénitas/etiología , Inglaterra/epidemiología , Monitoreo del Ambiente , Monitoreo Epidemiológico , Femenino , Humanos , Recién Nacido , Dióxido de Nitrógeno/análisis , Material Particulado/análisis , Material Particulado/toxicidad , Distribución de Poisson , Embarazo , Resultado del Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Factores de Riesgo , Dióxido de Azufre/análisisRESUMEN
BACKGROUND: The diagnosis of duodenal atresia is commonly made prenatally, either as an isolated lesion or due to its association with other chromosomal abnormalities (Robertson et al. in Semin Perinatol 18:182-195, 1994; Hemming and Rankin in J Prenat Diagn 27:1205-1211, 2007). The aim of this study was to describe the prevalence of associated anomalies, prenatal diagnostic accuracy and survival of cases of congenital duodenal atresia in our institution. METHODS: All cases of duodenal atresia registered with our local congenital anomaly register over a 10-year period, 1995-2004 inclusive, were studied, including those resulting in termination of pregnancies, stillbirths, intrauterine deaths and neonatal deaths. To ensure high-case ascertainment, data were cross checked with prenatal ultrasound, cytogenetic laboratory, pathology department and neonatal surgical data base. Data were analysed for associated anomalies, accuracy of prenatal diagnosis and neonatal outcomes. RESULTS: A total of 65 patients were initially diagnosed as having duodenal atresia, of these 4 were subsequently excluded (1 postnatal normal bowel and 3 high jejunal atresias). In the remaining 61 cases, 35 (57%) had an association with other congenital abnormalities and 26 (43%) were isolated anomalies. Thirty-five were male and 26 female (M:F = 1.4:1). Twenty-one out of 29 (72%) patients prenatally diagnosed, compared with 14 out of 32 (44%) patients diagnosed postnatally had associated anomalies. Duodenal atresia was suspected on routine prenatal ultrasonography at 20-week gestation in 33 cases and confirmed in 29 (48%) cases with 4 false-positive diagnoses (1 normal bowel and 3 high jejunal atresias). No prenatal diagnosis was made in 32 (52%) babies. Of the 61 cases, 53 were live births with 2 early neonatal deaths (1 cardiac and 1 VACTERL), 5 terminations, 2 intrauterine deaths and 1 stillbirth (Fig. 3). Overall neonatal survival was 96% (51 cases). Mortality in the group diagnosed prenatally was 34 % (10 cases). CONCLUSION: This study shows an overall increased association of duodenal atresia with Down's syndrome. In the group diagnosed prenatally, mortality as well as the association with other congenital anomalies was found to be higher. We have demonstrated a greater prenatal diagnostic accuracy, but confirm postnatal outcomes similar to previous studies.
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Obstrucción Duodenal/congénito , Atresia Intestinal/diagnóstico , Anomalías Múltiples , Síndrome de Down/complicaciones , Femenino , Enfermedades Fetales/diagnóstico por imagen , Humanos , Lactante , Recién Nacido , Atresia Intestinal/complicaciones , Atresia Intestinal/mortalidad , Masculino , Embarazo , Estudios Retrospectivos , Ultrasonografía PrenatalRESUMEN
OBJECTIVE: To 'map' the current (2004) state of prenatal screening in Europe. DESIGN: (i) Survey of country policies and (ii) analysis of data from EUROCAT (European Surveillance of Congenital Anomalies) population-based congenital anomaly registers. SETTING: Europe. POPULATION: Survey of prenatal screening policies in 18 countries and 1.13 million births in 12 countries in 2002-04. METHODS: (i) Questionnaire on national screening policies and termination of pregnancy for fetal anomaly (TOPFA) laws in 2004. (ii) Analysis of data on prenatal detection and termination for Down's syndrome and neural tube defects (NTDs) using the EUROCAT database. MAIN OUTCOME MEASURES: Existence of national prenatal screening policies, legal gestation limit for TOPFA, prenatal detection and termination rates for Down's syndrome and NTD. RESULTS: Ten of the 18 countries had a national country-wide policy for Down's syndrome screening and 14/18 for structural anomaly scanning. Sixty-eight percent of Down's syndrome cases (range 0-95%) were detected prenatally, of which 88% resulted in termination of pregnancy. Eighty-eight percent (range 25-94%) of cases of NTD were prenatally detected, of which 88% resulted in termination. Countries with a first-trimester screening policy had the highest proportion of prenatally diagnosed Down's syndrome cases. Countries with no official national Down's syndrome screening or structural anomaly scan policy had the lowest proportion of prenatally diagnosed Down's syndrome and NTD cases. Six of the 18 countries had a legal gestational age limit for TOPFA, and in two countries, termination of pregnancy was illegal at any gestation. CONCLUSIONS: There are large differences in screening policies between countries in Europe. These, as well as organisational and cultural factors, are associated with wide country variation in prenatal detection rates for Down's syndrome and NTD.
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Aborto Inducido/estadística & datos numéricos , Síndrome de Down/diagnóstico , Política de Salud , Defectos del Tubo Neural/diagnóstico , Diagnóstico Prenatal/estadística & datos numéricos , Síndrome de Down/tratamiento farmacológico , Síndrome de Down/economía , Europa (Continente)/epidemiología , Femenino , Pruebas Genéticas/estadística & datos numéricos , Edad Gestacional , Humanos , Embarazo , Trimestres del Embarazo , Encuestas y Cuestionarios , Ultrasonografía Prenatal/estadística & datos numéricosRESUMEN
The aim of this study is to establish the postnatal diagnosis and outcome of all abdominal cystic lesions diagnosed antenatally over a 13-year period. All prenatally suspected and postnatally confirmed intra-abdominal cysts seen and delivered between 1991 and 2004 were identified. Antenatal diagnosis, gestational age at delivery, sex and postnatal diagnosis and outcome were recorded. Fifty-five patients were identified with an antenatal diagnosis of abdominal cystic lesion. There were 53 live births and 2 intrauterine deaths. In 13 cases (24%) the cyst had resolved on a postnatal scan. Sixteen (29%) required surgical intervention postnatally. Twenty-six (47%) were given a "non-specific" diagnosis of abdominal cyst antenatally. Three (11%) of these non-specific cysts had resolved on postnatal scan. A "specific" diagnosis of the abdominal cyst was made antenatally in 29 cases (53%) of which 12 (43%) had the diagnosis confirmed postnatally. In ten (35%) of these there was a normal postnatal scan. Antenatal ultrasound scans may not reliably predict the exact pathological diagnosis of abdominal cystic lesions. However this study provides valuable information on the proportion of correctly diagnosed lesions and those that will persist into the postnatal period allowing more informative counselling for prospective parents.
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Abdomen , Quistes/diagnóstico por imagen , Enfermedades Fetales/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Recién Nacido , Masculino , Embarazo , Resultado del Embarazo , PronósticoRESUMEN
The reactions of boron halides with free base porphyrins under conditions where partial hydrolysis of the boron halides can occur give diboron porphyrin complexes containing BOB moieties in which each boron is bonded to two porphyrin nitrogen atoms. BF(3).OEt(2) with H(2)(por) gives B(2)OF(2)(por) (por = tpp, ttp, tpClpp, oep) which has an asymmetric structure in which one boron lies in the porphyrin plane (B(ip)) while the other lies above it (B(oop)). BCl(3).MeCN with H(2)(por) gives B(2)O(2)(BCl(3))(2)(por) which contains a four-membered B(2)O(2) ring and is stable only in the presence of excess BCl(3). BBr(3) with Li(2)(tpClpp) gives the dicationic complex [B(2)O(tpClpp)](2+) as its [BBr(4)](-) salt, and is the first example of a boron porphyrin containing three-coordinate boron to be structurally characterised. B(2)O(2)(BCl(3))(2)(por) can be chromatographed on basic alumina to give the hydroxyboron complex B(2)O(OH)(2)(por), which is deduced from its NMR spectra and DFT calculations to have a structure analogous to B(2)OF(2)(por). The OH protons are shifted upfield to near delta -4 (B(oop)-OH) and -10 (B(ip)-OH) by the diamagnetic porphyrin ring current. The reaction of either B(2)O(2)(BCl(3))(2)(por) or B(2)O(OH)(2)(por) (por = ttp, tpClpp) with alcohols (ROH, R = Et, 4-C(6)H(4)CH(3)) gives B(2)O(OR)(2)(por), which can in turn be converted to B(2)O(OR)(OH)(por) by repeated chromatography. The reaction of PhBCl(2) with H(2)(por) (por = ttp, tpClpp) gives B(2)O(Ph)(OH)(por) which has been characterised by spectroscopy in concert with DFT calculations. It is a further example of the B(2)OF(2)(por) structural type, in which the phenyl group is coordinated to the out-of-plane boron and the OH group to the in-plane boron, as are its derivatives B(2)O(Ph)(X)(tpClpp) (X = F, OEt). Steric drivers for the facile hydrolysis of haloboron porphyrins relative to their dipyrromethene and expanded porphyrin counterparts are discussed.
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Compuestos de Boro/química , Porfirinas/química , Boranos/química , Compuestos de Boro/síntesis química , Cloruros/química , Hidrólisis , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Porfirinas/síntesis químicaRESUMEN
AIM: To assess the attitudes of healthcare workers within the UK towards identification marking of removable prostheses, and quantify the frequency with which this is currently undertaken. DESIGN: A postal questionnaire-based study. SETTING: The study was undertaken within the UK between 2002 and 2006 and surveyed prosthodontists working in a wide range of clinical settings. SUBJECTS AND METHODS: Questionnaires were sent to two sample groups: 1. Specialists in prosthodontics registered on the GDC specialist list; 2. Nursing staff in elderly care homes within the locality of Glasgow. RESULTS: Return rate of questionnaires from prosthodontic specialists was high, with 119 from 160 (74%) completed and returned. 54.9% of prosthodontic specialists carried out complete denture marking in their clinical practice and 40.9% undertook identification marking of partial removable prostheses. The vast majority (81.0%) of specialists indicated that denture identification marking was a worthwhile procedure. Furthermore, 68.9% thought the introduction of some form of guideline would be beneficial. Differences in the frequency of denture marking existed between varying clinical environments. Denture marking was not undertaken by healthcare workers within any of the surveyed care homes. CONCLUSION: The overwhelming opinion of prosthodontic specialists within the UK promotes the use of denture marking as a routine procedure.
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Actitud del Personal de Salud , Identificación de la Prótesis Dental/estadística & datos numéricos , Distribución de Chi-Cuadrado , Odontólogos/psicología , Identificación de la Prótesis Dental/métodos , Humanos , Prostodoncia/métodos , Encuestas y Cuestionarios , Reino UnidoRESUMEN
One hundred Hampshire x Duroc cross-bred pigs (HD) and 100 NE Index line (I) pigs were infected with porcine reproductive and respiratory syndrome (PRRS) virus and evaluated for resistance/susceptibility. Controls (100/line) were uninfected littermates to the infected pigs. Viremia, change in weight (WTdelta), and rectal temperature at 0, 4, 7, and 14 d postinfection were recorded. Lung, bronchial lymph node (BLN), and blood tissue were collected at necropsy (14 d postinfection). The first principal component from principal component analyses of all variables was used to rank the pigs for phenotypic response to PRRS virus. Low responders (low PRRS burden) had high WTdelta, low viremia, and few lung lesions; high responders (high PRRS burden) had low WTdelta, high viremia, and many lesions. The RNA was extracted from lung and BLN tissue of the 7 highest and 7 lowest responders per line and from each of their littermates. Expression of 11 innate and T helper 1 immune markers was evaluated with cDNA in a 2 x 2 x 2 factorial design. Significant upregulation in lung, lymph, or both of infected pigs relative to controls occurred for all but one gene. Expression differences were greater in HD than I pigs. Significant downregulation for certain immune genes in low pigs, relative to littermate controls, was detected in lung and BLN, particularly in line I. Serum levels of the immune cytokines affirmed the gene expression differences. High preinfection serum levels of IL 8 were significantly associated with PRRS virus-resistant, low pigs. After infection, low expression of interferon gamma in cDNA and in serum was also correlated with PRRS virus resistance. Important genetic associations were revealed for fine mapping of candidate genes for PRRS virus resistance and determining the causative alleles.
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Citocinas/biosíntesis , Síndrome Respiratorio y de la Reproducción Porcina/genética , Síndrome Respiratorio y de la Reproducción Porcina/inmunología , Virus del Síndrome Respiratorio y Reproductivo Porcino/inmunología , Animales , Temperatura Corporal , Peso Corporal , Citocinas/genética , Citocinas/inmunología , Susceptibilidad a Enfermedades/veterinaria , Femenino , Regulación Viral de la Expresión Génica , Variación Genética , Pulmón/patología , Pulmón/virología , Ganglios Linfáticos/virología , Masculino , Síndrome Respiratorio y de la Reproducción Porcina/virología , Análisis de Componente Principal , Distribución Aleatoria , Porcinos , Factores de Tiempo , Viremia/veterinaria , Viremia/virologíaRESUMEN
OBJECTIVES: To assess the accuracy of the prenatal ultrasound finding of subjectively small/absent stomach bubble in the prenatal diagnosis of tracheo-oesophageal fistula and oesophageal atresia (TOF/OA). METHODS: A retrospective study of prenatal ultrasound scans showing small/absent stomach bubble was carried out between 1st January 1994 and 31st December 2003. RESULTS: There were 62 cases with prenatally suspected (n = 40) and/or post-natally diagnosed (n = 22) TOF/OA. Among the 40 cases of prenatally suspected TOF/OA 15 were thought to be isolated and 25 non-isolated. Of the 15 suspected isolated cases, 7 were normal and 8 had TOF/OA (5 isolated + 3 TOF/OA with another anomaly) at delivery. Among the 25 cases of prenatally suspected non-isolated TOF/OA, there was confirmation in only two cases, in the remaining 23 cases other anomalies were confirmed but TOF/OA was not present.Twenty-two babies with TOF/OA were identified in whom there had been no prenatal ultrasound suspicion on ultrasound scanning. Six had isolated TOF/OA and 16 had non-isolated TOF/OA. CONCLUSION: Of the 32 cases of confirmed TOF/OA,10 (31%) were suspected prenatally. If the TOF/OA was an isolated anomaly (11 cases), the prenatal detection rate was 45%. Interpretation of ultrasound findings suspicious of TOF/OA requires caution, particularly, when there are associated multiple anomalies on scan.
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Atresia Esofágica/diagnóstico por imagen , Fístula Traqueoesofágica/diagnóstico por imagen , Ultrasonografía Prenatal , Femenino , Humanos , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Fístula Traqueoesofágica/congénitoRESUMEN
Since the mid-1980s, our understanding of nutrient limitation of oceanic primary production has radically changed. Mesoscale iron addition experiments (FeAXs) have unequivocally shown that iron supply limits production in one-third of the world ocean, where surface macronutrient concentrations are perennially high. The findings of these 12 FeAXs also reveal that iron supply exerts controls on the dynamics of plankton blooms, which in turn affect the biogeochemical cycles of carbon, nitrogen, silicon, and sulfur and ultimately influence the Earth climate system. However, extrapolation of the key results of FeAXs to regional and seasonal scales in some cases is limited because of differing modes of iron supply in FeAXs and in the modern and paleo-oceans. New research directions include quantification of the coupling of oceanic iron and carbon biogeochemistry.