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 email@example.com
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.
Little is known about the types of intestinal parasites that infected people living in prehistoric Britain. The Late Bronze Age archaeological site of Must Farm was a pile-dwelling settlement located in a wetland, consisting of stilted timber structures constructed over a slow-moving freshwater channel. At excavation, sediment samples were collected from occupation deposits around the timber structures. Fifteen coprolites were also hand-recovered from the occupation deposits; four were identified as human and seven as canine, using fecal lipid biomarkers. Digital light microscopy was used to identify preserved helminth eggs in the sediment and coprolites. Eggs of fish tapeworm (Diphyllobothrium latum and Diphyllobothrium dendriticum), Echinostoma sp., giant kidney worm (Dioctophyma renale), probable pig whipworm (Trichuris suis) and Capillaria sp. were found. This is the earliest evidence for fish tapeworm, Echinostoma worm, Capillaria worm and the giant kidney worm so far identified in Britain. It appears that the wetland environment of the settlement contributed to establishing parasite diversity and put the inhabitants at risk of infection by helminth species spread by eating raw fish, frogs or molluscs that flourish in freshwater aquatic environments, conversely the wetland may also have protected them from infection by certain geohelminths.
The Murchison Widefield Array is a low-frequency Square Kilometre Array precursor located at the Murchison Radio-astronomy Observatory in Western Australia. Primarily designed as an imaging telescope, but with a flexible signal path, the capabilities of this telescope have recently been extended to include off-line incoherent and tied-array beam formation using recorded antenna voltages. This has provided the capability for high-time and frequency resolution observations, including a pulsar science program. This paper describes the algorithms and pipeline that we have developed to form the tied-array beam products from the summation of calibrated signals of the antenna elements, and presents example polarimetric profiles for PSRs J0437-4715 and J1900-2600 at 185 MHz.
We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
The late Miocene is a time of strong environmental change in SW Asia. Himalayan foreland stable isotope data show a shift in the dominant vegetation of the flood plains away from trees and shrubs towards more C4 grasslands at a time when oceanic upwelling increased along the Oman margin. We present integrated geochemical and colour spectral records from International Ocean Discovery Program Site U1456 in the eastern Arabian Sea to reconstruct changing chemical weathering and erosion, as well as relative humidity during this climatic transition. Increasing hematite/goethite ratios derived from spectral data are consistent with long-term drying after c. 7.7 Ma. Times of dry conditions are largely associated with weaker chemical alteration measured by K/Rb and reduced coarse clastic flux, constrained by Si/Al and Zr/Al. A temporary phase of increased humidity from 6.3 to 5.95 Ma shows a reversal to stronger weathering and erosion. Wetter conditions can result in both more and less alteration due to the nonlinear relationship between weathering rates, precipitation and sediment transport times. Trends in relative aridity do not follow existing palaeoceanographic records and are not apparently linked to changes in Tibetan or Himalayan elevation, but more closely correlate with global cooling. An apparent opposing trend in the humidity evolution in the Indus compared to southern China, as tracked by spectrally estimated hematite/goethite, likely reflects differences in the topography in the Indus compared to the Pearl River drainage basins, as well as the generally wetter climate in southern China.
The early village at Çatalhöyük (7100–6150 BC) provides important evidence for the Neolithic and Chalcolithic people of central Anatolia. This article reports on the use of lipid biomarker analysis to identify human coprolites from midden deposits, and microscopy to analyse these coprolites and soil samples from human burials. Whipworm (Trichuris trichiura) eggs are identified in two coprolites, but the pelvic soil samples are negative for parasites. Çatalhöyük is one of the earliest Eurasian sites to undergo palaeoparasitological analysis to date. The results inform how intestinal parasitic infection changed as humans modified their subsistence strategies from hunting and gathering to settled farming.
Despite the magnitude and protracted nature of the Rohingya refugee situation, there is limited information on the culture, mental health and psychosocial wellbeing of this group. This paper, drawing on a report commissioned by the United Nations High Commissioner for Refugees (UNHCR), aims to provide a comprehensive synthesis of the literature on mental health and psychosocial wellbeing of Rohingya refugees, including an examination of associated cultural factors. The ultimate objective is to assist humanitarian actors and agencies in providing culturally relevant Mental Health and Psychosocial Support (MHPSS) for Rohingya refugees displaced to Bangladesh and other neighbouring countries.
We conducted a systematic search across multiple sources of information with reference to the contextual, social, economic, cultural, mental health and health-related factors amongst Rohingya refugees living in the Asia-Pacific and other regions. The search covered online databases of diverse disciplines (e.g. medicine, psychology, anthropology), grey literature, as well as unpublished reports from non-profit organisations and United Nations agencies published until 2018.
The legacy of prolonged exposure to conflict and persecution compounded by protracted conditions of deprivations and displacement is likely to increase the refugees' vulnerability to wide array of mental health problems including posttraumatic stress disorder, anxiety, depression and suicidal ideation. High rates of sexual and gender-based violence, lack of privacy and safe spaces and limited access to integrated psychosocial and mental health support remain issues of concern within the emergency operation in Bangladesh. Another challenge is the limited understanding amongst the MHPSS personnel in Bangladesh and elsewhere of the language, culture and help-seeking behaviour of Rohingya refugees. While the Rohingya language has a considerable vocabulary for emotional and behavioural problems, there is limited correspondence between these Rohingya terms and western concepts of mental disorders. This hampers the provision of culturally sensitive and contextually relevant MHPSS services to these refugees.
The knowledge about the culture, context, migration history, idioms of distress, help-seeking behaviour and traditional healing methods, obtained from diverse sources can be applied in the design and delivery of culturally appropriate interventions. Attention to past exposure to traumatic events and losses need to be paired with attention for ongoing stressors and issues related to worries about the future. It is important to design MHPSS interventions in ways that mobilise the individual and collective strengths of Rohingya refugees and build on their resilience.
In the measurement of residual stresses in hardened carbon steels by X-ray diffraction the principal difficulty encountered is determining the precise location of the broad diffraction lines. Christenson and RowlandM have proposed a workable technique, but it entails a complicated correction calculation. A simplified correction procedure, based on theoretical considerations, will be described which shortens the time required to obtain accurate data and cuts the time required for calculation to a fraction of that required for the previous method.
It can be shown that the asymmetry of the broad diffraction lines in the back reflection region is largely due to 6 dependent intensity factors. Thus, the proposed correction procedure uses a multiplicative correction to peak intensity which includes all significant geometrical and absorption factors. The line position is then determined accurately as the axis of a parabola fitted to the corrected data. Since the data is taken in the vicinity of the peak, the time required to obtain accurate data is reduced and furthermore it is possible to determine residual stresses in as-quenched steel even though the structure is tetragonal.
Examples of the type of stresses measured and the correlation between this new method and that of Christenson and Rowland will be presented.
In this study, we have examined ceramic matrix composites with silicon carbide fibers in a melt-infiltrated silicon carbide matrix (SiC/SiC). We subjected samples to tensile loads while collecting micro X-ray computed tomography images. The results showed the expected crack slowing mechanisms and lower resistance to crack propagation where the fibers ran parallel and perpendicular to the applied load respectively. Cracking was shown to initiate not only from the surface but also from silicon inclusions. Post heat-treated samples showed longer fiber pull-out than the pristine samples, which was incompatible with previously proposed mechanisms. Evidence for oxidation was identified and new mechanisms based on oxidation or an oxidation assisted boron nitride phase transformation was therefore proposed to explain the long pull-out. The role of oxidation emphasizes the necessity of applying oxidation resistant coatings on SiC/SiC.
Essential variables to consider for an efficient control strategy for invasive plants include dispersion pattern (i.e., satellite or invasion front) and patch expansion rate. These variables were demonstrated for buffelgrass [Pennisetum ciliare (L.) Link], a C4 perennial grass introduced from Africa, which has invaded broadly around the world. The study site was along a roadway in southern Arizona (USA). The P. ciliare plant distributions show the pattern of clumping associated with the satellite (nascent foci) colonization pattern (average nearest neighbor test, z-score −47.2, P<0.01). The distance between patches ranged from 0.743 to 12.8 km, with an average distance between patches of 5.6 km. Median patch expansion rate was 271% over the 3-yr monitoring period versus 136% found in other studies of established P. ciliare patches. Targeting P. ciliare satellite patches as a control strategy may exponentially reduce the areal doubling time, while targeting the largest patches may have less effect on the invasion speed.
Large herbivores can act as keystone species that strongly influence their communities. During the Pliocene and Pleistocene, Australia was dominated by a number of large to gigantic marsupial herbivore taxa. Many of these have been understudied quantitatively with regard to their ecology; and identifying the diet of these species will improve our understanding of not only their ecologies, but also of past environments. Recent research has found that cranial morphology among kangaroos and wallabies corresponds with foraging behaviors and mechanical properties of preferred plant tissues. Here we apply shape analysis and computational biomechanics to test the hypothesis: that feeding ecology is associated with craniofacial morphology across a taxonomically broad sample of diprotodont herbivores. Based on our results we predict the diet of an extinct short-faced kangaroo, Simosthenurus occidentalis. We find that biting behaviors are reflected in craniofacial morphology, but that these are more a reflection of the hardest bites required for their lifestyle, rather than diet composition alone. A combination of a very short face, robust musculoskeletal features, and dental arrangements predict that S. occidentalis was a browser, capable of consuming particularly resistant, bulky plant matter. These features were largely conserved among other short-faced kangaroos and may have offset the unpredictable availability of quality forage during the climatically variable Pleistocene epoch, contributing to their prolific diversification during this time.
Calling in staff and preparing the operating room for an urgent surgical procedure is a significant draw on hospital resources and disrupts care of other patients. It has been common practice to treat open fractures on an urgent basis. HTA methods can be applied to examine this prioritization of care, just like they can be applied to the acquisition of drugs and devices.
Our center completed a rapid systematic review of guidelines, systematic reviews, and primary clinical evidence, on urgent surgical debridement and stabilization of open fractures of long bones (“urgent” being defined as within six hours of the injury) compared to surgical debridement and reduction performed at a later time point. Meta-analyses were performed for infection and non-union outcomes and the GRADE system was used to assess the strength of evidence for each conclusion.
We found no published clinical guidelines for the urgency of treating open fractures. A good systematic review on the topic was published in 2012. We found six cohort studies published since completion of the earlier review. The summary odds ratio for any infection in patients with later treatment was 0.97 (95% confidence interval (CI) 0.78–1.22, sixteen studies, 3,615 patients) and for deep or “major” infections was 1.00 (95% CI 0.74–1.34, nine studies, 2,013 patients). The summary odds ratio of non-union with later treatment was 0.95 (95% CI 0.65–1.41, six studies, 1,308 patients). There was no significant heterogeneity in any of the results (I-squared = 0 percent) and no apparent trends in the results as a function of study size or publication date. We graded the strength of each of the conclusions as very low because they were based on cohort studies where the treating physician could elect immediate treatment for patients with severe soft-tissue injuries or patients at risk of complications. This raises the risk of spectrum bias.
Default urgent scheduling of patients with open fractures for surgical debridement and stabilization does not appear to reduce the risk of infection or fracture non-union. Based on this information, our surgery department managers no longer schedule patients with open fractures for immediate surgery unless there are specific circumstances necessitating it.
The US Agency for Healthcare Research and Quality (AHRQ) Evidence-based Practice Center (EPC) program sponsors the development of systematic reviews to inform clinical policy and practice. The EPC program sought to better understand how health systems identify and use this evidence.
Representatives from eleven EPCs, the EPC Scientific Resource Center, and AHRQ developed a semi-structured interview script to query a diverse group of nine Key Informants (KIs) involved in health system quality, safety and process improvement about how they identify and use evidence. Interviews were transcribed and qualitatively summarized into key themes.
All KIs reported that their organizations have either centralized quality, safety, and process improvement functions within their system, or they have partnerships with other organizations to conduct this work. There was variation in how evidence was identified, with larger health systems having medical librarians and central bureaus to gather and disseminate information and smaller systems having local chief medical officers or individual clinicians do this work. KIs generally prefer guidelines, especially those with treatment algorithms, because they are actionable. They like systematic reviews because they efficiently condense study results and reconcile conflicting data. They prefer information from systematic reviews to be presented as short digestible summaries with the full report available on demand. KIs preferred systematic reviews from reputable entities and those without commercial bias. Some of the challenges KIs reported include how to resolve conflicting evidence, the generalizability of evidence to local needs, determining whether the evidence is up-to-date, and the length of time required to generate reviews. The topics of greatest interest included predictive analytics, high-value care, advance care planning, and care coordination. To increase awareness of AHRQ EPC reviews, KIs suggest alerting people at multiple levels in a health-system when new evidence reports are available and making reports easier to find in common search engines.
Systematic reviews are valued by health system leaders. To be most useful they should be easy to locate and available in different formats targeted to the needs of different audiences.
We sought to explore factors associated with depressive symptom severity among older persons (≥60 years of age) and to compare the depressive symptoms commonly experienced by older elderly (≥75 years) with those commonly experienced by younger elderly (<75 years).
Secondary analysis was conducted on data from a nationally representative survey.
Four parishes in Jamaica.
A total of 2,943 older community dwellers participated.
The survey included the Zung Self-rating Depression Scale (ZSDS), the Mini Mental State Examination (MMSE), and items on age, sex, and educational level. Linear regression analysis was used to determine the association between ZSDS score and: age, sex, MMSE score, and educational level. Logistic regression analysis was used to determine, for each ZSDS item, whether particular responses were more associated with older or younger elderly.
Higher ZSDS scores were associated with increasing age (B = 0.13, p < 0.001), lower MMSE score (B = −0.42, p < 0.001), the female sex (B = 3.52, p < 0.001), and lower educational level (B = −1.27, p < 0.001). The ZSDS items that were endorsed significantly more (p < 0.05) by older elderly related to negative evaluations about their functionality and value. Hopelessness was also more prominent among the older elderly. The items that were endorsed significantly more (p < 0.05) by the younger elderly had less of a focus.
Among older persons, increasing age was associated with marginally higher levels of depressive symptoms. Female gender, cognitive deficits, preoccupations about value and functionality, and feelings of hopelessness may serve as useful screening parameters.
To evaluate the relationships between maternal fish consumption and pregnancy outcomes in a large, population-based sample of women in the USA.
We collected average fish consumption prior to pregnancy using a modified version of the semi-quantitative Willett FFQ. We estimated adjusted OR (aOR) and 95 % CI for associations between different levels of fish consumption and preterm birth (<37 weeks), early preterm birth (<32 and <35 weeks) and small-for-gestational-age infants (SGA; <10th percentile).
The National Birth Defects Prevention Study (NBDPS).
Control mother–infant pairs with estimated delivery dates between 1997 and 2011 (n 10 919).
No significant associations were observed between fish consumption and preterm birth or early preterm birth (aOR = 0·7–1·0 and 0·7–0·9, respectively). The odds of having an SGA infant were elevated (aOR = 2·1; 95 % CI 1·2, 3·4) among women with daily fish consumption compared with women consuming fish less than once per month. No associations were observed between other levels of fish consumption and SGA (aOR = 0·8–1·0).
High intake of fish was associated with twofold higher odds of having an SGA infant, while moderate fish consumption prior to pregnancy was not associated with preterm or SGA. Our study, like many other studies in this area, lacked information regarding preparation methods and the specific types of fish consumed. Future studies should incorporate information on nutrient and contaminant contents, preparation methods and biomarkers to assess these relationships.