Please note, due to essential maintenance online transactions will not be possible between 02:30 and 04:00 BST, on Tuesday 17th September 2019 (22:30-00:00 EDT, 17 Sep, 2019). We apologise for any inconvenience.
To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
An unexpected increase in gastroenteritis cases was reported by healthcare workers on the KwaZulu-Natal Coast, South Africa, January 2017 with >600 cases seen over a 3-week period. A case–control study was conducted to identify the source and risk factors associated with the outbreak so as to recommend control and prevention measures. Record review identified cases and controls and structured-telephonic interviews were conducted to obtain exposure history. Stool specimens were collected from 20 cases along with environmental samples and both screened for enteric pathogens. A total of 126 cases and 62 controls were included in the analysis. The odds of developing gastroenteritis were 6.0 times greater among holiday makers than residents (95% confidence interval (CI) 2.0–17.7). Swimming in the lagoon increased the odds of developing gastroenteritis by 3.3 times (95% CI 1.06–10.38). Lagoon water samples tested positive for norovirus (NoV) GI.6, GII.3 and GII.6, astrovirus and rotavirus. Eleven (55%) stool specimens were positive for NoV with eight genotyped as GI.1 (n = 2), GI.5 (n = 3), GI.6 (n = 2), and GI.7 (n = 1). A reported sewage contamination event impacting the lagoon was the likely source with person-to-person spread perpetuating the outbreak. Restriction to swimming in the lagoon was apparently ineffective at preventing the outbreak, possibly due to inadequate enforcement, communication and signage strategies.
Immature fruit fly stages of the family Tephritidae are commonly intercepted on breadfruit from Pacific countries at the New Zealand border but are unable to be identified to the species level using morphological characters. Subsequent molecular identification showed that they belong to Bactrocera xanthodes, which is part of a species complex that includes Bactrocera paraxanthodes, Bactrocera neoxanthodes and an undescribed species. To establish a more reliable molecular identification system for B. xanthodes, a reference database of DNA barcode sequences for the 5’-fragment of COI gene region was constructed for B. xanthodes from Fiji, Samoa and Tonga. To better understand the species complex, B. neoxanthodes from Vanuatu and B. paraxanthodes from New Caledonia were also barcoded. Using the results of this analysis, real-time TaqMan polymerase chain reaction (PCR) assays for the detection of B. xanthodes complex and for the three individual species of the complex were developed and validated. The assay showed high specificity for the target species, with no cross-reaction observed for closely related organisms. Each of the real-time PCR assays is sensitive, detecting the target sequences at concentrations as low as ten copies µl−1 and can be used as either singleplex or multiplex formats. This real-time PCR assay for B. xanthodes has been successfully applied at the borders in New Zealand, leading to the rapid identification of intercepted Tephritidae eggs and larvae. The developed assays will be useful biosecurity tools for rapid detection of species in the B. xanthodes complex worldwide.
Sustainable ruminant production systems depend on the ability of livestock to utilize increased quantities of grazed herbage. The current study aimed to compare the effect of white clover (WC) inclusion and perennial ryegrass (PRG) ploidy on herbage dry matter (DM) production, plant morphology, nutritive value and biological nitrogen (N) fixation (BNF) under high N fertilizer use (250 kg N/ha) and high stocking rates (2.75 livestock units/ha). Four sward treatments (diploid-only, tetraploid-only, diploid-WC, tetraploid-WC) were evaluated over a full grazing season at a farmlet scale. White clover inclusion had a significant effect on herbage DM production, herbage growth rate, tiller density, organic matter digestibility, crude protein and BNF. Tetraploid swards had a lower tiller density, lower sward WC content and post-grazing sward height and increased organic matter digestibility and crude protein than diploid swards. White clover inclusion improved herbage DM production and nutritive value across a full grazing season, with tetraploid and diploid swards producing similar herbage DM yields across the year. Perennial ryegrass ploidy had an effect on WC morphology as plants in diploid-WC swards had narrower, longer stolons, fewer branches and more petioles than tetraploid-WC swards. The current study highlights the benefit of including WC in grass-based systems under a high N fertilizer regime and high stocking rate.
This study estimates the symptomatology of attention deficit–hyperactivity disorder (ADHD) in adult mental health services (AMHS) outpatient clinics.
All consecutive patients attending any of the outpatients’ clinics in Sligo/Leitrim AMHS were invited to participate. Participants completed the Adult ADHD Self-Report Scale (ASRS) and the Wender Utah Rating Scale (WURS) self-report. Clinical notes were reviewed to identify those with a pre-existing ADHD diagnosis.
From 822 attending the clinics, 62 did not meet inclusion criteria, 97 declined to participate and 29 had incomplete data in either of the screening scales, leaving 634 (77%) eligible for full study analysis. Mean age was 40.38 (s.d.: 12.85), and 326 (51.4%) were females. In total, 215 (33.9%) screened positive on the WURS for childhood onset ADHD and 219 (34.5%) participants scored positive on the ASRS. Applying a more stringent criteria of scoring above cut-offs on both scales, suggested 131 (20.7%) screened positive on both. Only three (2.3%) had a prior clinical diagnosis.
This preliminary study suggests the possibility of relatively higher rates of ADHD in a general AMHS than previously thought, however, given the possibility of overlapping symptoms with other major psychiatric disorders in adulthood and recall bias further research is needed before drawing firm conclusions.
The mass changes of the Gulf of Alaska (GoA) glaciers are computed from the Gravity Recovery and Climate Experiment (GRACE) inter-satellite range-rate data for the period April 2003–September 2007. Through the application of unique processing techniques and a surface mass concentration (mascon) parameterization, the mass variations in the GoA glacier regions have been estimated at high temporal (10 day) and spatial (2 × 2 arc-degrees) resolution. The mascon solutions are directly estimated from a reduction of the GRACE K-band inter-satellite range-rate data and, unlike previous GRACE solutions for the GoA glaciers, do not exhibit contamination by leakage from mass change occurring outside the region of interest. The mascon solutions reveal considerable temporal and spatial variation within the GoA glacier region, with the largest negative mass balances observed in the St Elias Mountains including the Yakutat and Glacier Bay regions. The most rapid losses occurred during the 2004 melt season due to record temperatures in Alaska during that year. The total mass balance of the GoA glacier region was −84 ± 5 Gt a−1 contributing 0.23 ± 0.01 mm a−1 to global sea-level rise from April 2003 through March 2007. Highlighting the large seasonal and interannual variability of the GoA glaciers, the rate determined over the period April 2003–March 2006 is −102 ± 5 Gt a−1, which includes the anomalously high temperatures of 2004 and does not include the large 2007 winter balance-year snowfall. The mascon solutions agree well with regional patterns of glacier mass loss determined from aircraft altimetry and in situ measurements.
Cyg X-3 underwent a series of giant radio outbursts beginning on September 28, 1982 (Geldzahler et al. 1983). The flux densities at 2.7 and 8.1 GHz (11.1, 3.71 cm respectively, see Figure 1) were measured with the 2.4 km baseline of the Green Bank interferometer once every three days before October 5, 1982 (= JD 244 5248) and three times daily thereafter.
In Table I we present the list of 38 celestial objects that have been observed since January 1978 at 2.7 and 8.1 GHz with the Green Bank interferometer. The sources fall naturally into three categories: radio stars, possibly Galactic sources, and extragalactic sources. SS433, Cyg X-3, and each extrgalactic source is measured several times per day while the other sources are measured once every three days. Reports on the entire program will be found in Geldzahler et al. (1983a), and on specific sources: SS433—Johnston et al. (1983a), BL Lac—Johnston et al. (1983b), Cyg X-3—Geldzahler et al. (1983b) and elsewhere in this volume), and CTA 26—Spencer et al. (1983).
We have determined the ice mass evolution of the Antarctic and Greenland ice sheets (AIS and GIS) and Gulf of Alaska (GOA) glaciers from a new GRACE global solution of equal-area surface mass concentration parcels (mascons) in equivalent height of water. The mascons were estimated directly from the reduction of the inter-satellite K-band range-rate (KBRR) observations, taking into account the full noise covariance, and formally iterating the solution. The new solution increases signal recovery while reducing the GRACE KBRR observation residuals. The mascons were estimated with 10 day and 1 arcdeg equal-area sampling, applying anisotropic constraints. An ensemble empirical mode decomposition adaptive filter was applied to the mascon time series to compute annual mass balances. The details and causes of the spatial and temporal variability of the land-ice regions studied are discussed. The estimated mass trend over the total GIS, AIS and GOA glaciers for the time period 1 December 2003 to 1 December 2010 is −380 ± 31 Gt a−1, equivalent to −1.05 ± 0.09 mm a−1 sea-level rise. Over the same time period we estimate the mass acceleration to be −41 ± 27 Gt a−2 , equivalent to a −0.11 ± 0.08 mm a−2 sea-level acceleration. The trends and accelerations are dependent on significant seasonal and annual balance anomalies.
Although repeatedly associated with white matter microstructural alterations, bipolar disorder (BD) has been relatively unexplored using complex network analysis. This method combines structural and diffusion magnetic resonance imaging (MRI) to model the brain as a network and evaluate its topological properties. A group of highly interconnected high-density structures, termed the ‘rich-club’, represents an important network for integration of brain functioning. This study aimed to assess structural and rich-club connectivity properties in BD through graph theory analyses.
We obtained structural and diffusion MRI scans from 42 euthymic patients with BD type I and 43 age- and gender-matched healthy volunteers. Weighted fractional anisotropy connections mapped between cortical and subcortical structures defined the neuroanatomical networks. Next, we examined between-group differences in features of graph properties and sub-networks.
Patients exhibited significantly reduced clustering coefficient and global efficiency, compared with controls globally and regionally in frontal and occipital regions. Additionally, patients displayed weaker sub-network connectivity in distributed regions. Rich-club analysis revealed subtly reduced density in patients, which did not withstand multiple comparison correction. However, hub identification in most participants indicated differentially affected rich-club membership in the BD group, with two hubs absent when compared with controls, namely the superior frontal gyrus and thalamus.
This graph theory analysis presents a thorough investigation of topological features of connectivity in euthymic BD. Abnormalities of global and local measures and network components provide further neuroanatomically specific evidence for distributed dysconnectivity as a trait feature of BD.
We present results of the first large (> 100 stars) infrared coronographic search for substellar companions to nearby stars. The search consisted of two surveys of stars chosen for their youth and proximity to Earth: 1.) a 178 star infrared survey at Steward and Lick Observatories, with optical followup from Keck Observatory, capable of detecting companions with masses greater than 30MJ, orbiting between about 75 and 300 AU, 2.) a 102 star survey using the Keck telescope, capable of detecting extrasolar brown dwarfs and planets typically more massive than 10 MJ, orbiting between about 75 and 300 AU.
This research resulted in the discovery of one brown dwarf companion, zero planets and 23 double stars. The frequency of brown dwarf companions (of any mass) to G, K and M stars orbiting between 75 and 300 AU is measured to be 1 ± 1 %. The frequency of massive (> 30 MJ) brown dwarf companions is found to be 0.6 ± 0.6 %. The frequency of giant planets with masses larger than 10 MJ, between 75 and 300 AU, is measured here for the first time to be no more than about 3 %.
This report will try to review briefly the work achieved from 1982 to 1984 in different “subjects to be considered by Commission 31 Time” as adopted in Grenoble 1976. It contains also information provided by Commission members, for which hearty thanks are to be given. The limitation of space required the abbrevation of some institution reports.
The examination of a collection of nudibranchs (Mollusca: Gastropoda: Heterobranchia) obtained during several expeditions to international waters off Newfoundland, North Atlantic, revealed the presence of rare species, new records for the area, and an undescribed species of Tritonia (described herein). This includes the first record of Dendronotus niveus Ekimova, Korshunova, Schepetov, Neretina, Sanamyan and Martynov, 2015 from the Atlantic Ocean and numerous specimens of the rare species Doridoxa ingolfiana Bergh, 1899, which is here redescribed. Other species collected are Flabellina cf. salmonacea (Couthouy, 1838), Dendronotus frondosus (Ascanius, 1774), Dendronotus robustus A. E. Verrill, 1870, Aldisa zetlandica (Alder & Hancock, 1854), Onchidoris bilamellata (Linnaeus, 1767), Colga villosa (Odhner, 1907) as well as an unidentified species of Aeolidiella. Anatomical characteristics and genetic barcode data are used to identify the species whenever it was possible. Ecological data, including substrate, associated fauna and bathymetric range are provided.
The burden and aetiology of type 2 diabetes (T2D) and its microvascular complications may be influenced by varying behavioural and lifestyle environments as well as by genetic susceptibility. These aspects of the epidemiology of T2D have not been reliably clarified in sub-Saharan Africa (SSA), highlighting the need for context-specific epidemiological studies with the statistical resolution to inform potential preventative and therapeutic strategies. Therefore, as part of the Human Heredity and Health in Africa (H3Africa) initiative, we designed a multi-site study comprising case collections and population-based surveys at 11 sites in eight countries across SSA. The goal is to recruit up to 6000 T2D participants and 6000 control participants. We will collect questionnaire data, biophysical measurements and biological samples for chronic disease traits, risk factors and genetic data on all study participants. Through integrating epidemiological and genomic techniques, the study provides a framework for assessing the burden, spectrum and environmental and genetic risk factors for T2D and its complications across SSA. With established mechanisms for fieldwork, data and sample collection and management, data-sharing and consent for re-approaching participants, the study will be a resource for future research studies, including longitudinal studies, prospective case ascertainment of incident disease and interventional studies.
The Durban Diabetes Study (DDS) is a population-based cross-sectional survey of an urban black population in the eThekwini Municipality (city of Durban) in South Africa. The survey combines health, lifestyle and socioeconomic questionnaire data with standardised biophysical measurements, biomarkers for non-communicable and infectious diseases, and genetic data. Data collection for the study is currently underway and the target sample size is 10 000 participants. The DDS has an established infrastructure for survey fieldwork, data collection and management, sample processing and storage, managed data sharing and consent for re-approaching participants, which can be utilised for further research studies. As such, the DDS represents a rich platform for investigating the distribution, interrelation and aetiology of chronic diseases and their risk factors, which is critical for developing health care policies for disease management and prevention. For data access enquiries please contact the African Partnership for Chronic Disease Research (APCDR) at email@example.com or the corresponding author.
The nature of the irregular fluctuations in the speed of the Earth's rotation was investigated using ninety-day means of UT2 - A.1 determined at the U. S. Naval Observatory. Data from June 1955 to April 1978 were included in this study. Statistical analysis of the excess length of day shows no evidence for the persistence of discrete values for periods on the order of five years. No statistical basis for the existence of discrete “turning points” in the rotational speed could be found.
Spectral analysis of the acceleration data shows that the rotational acceleration of the Earth during this period of time may be represented by a constant term plus random changes in acceleration occurring with a frequency greater than once per year. The magnitude of these changes appear to be consistent with estimates of meteorologically induced changes in the rotational acceleration.
An autoregressive integrated moving average (ARIMA) model was fit to the excess length of day data. This model permits simulated series of excess length of day data to be constructed. These simulated series show a statistical similarity to observations made since 1820. However the apparently large changes in the acceleration which occurred around 1870 and 1900 are twice that which can be reasonably accounted for by this model. The details of this analysis will be published later.