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Anecdotal evidence suggests the use of bolus tube feeding is increasing in long term home enteral tube feed (HETF) patients. A cross-sectional survey to assess the prevalence of bolus tube feeding and to characterise these patients was undertaken. Dietitians from 10 centres across the UK collected data on all adult HETF patients on the dietetic caseload receiving bolus tube feeding, (n=604, 60% male, age 58years). Demographic data, reasons for tube and bolus feeding, tube and equipment types, feeding method and patients’ complete tube feeding regimens were recorded. Over a third of patients receiving HETF used bolus feeding (37%). Patients were long-term tube fed (4.1years tube feeding, 3.5years bolus tube feeding), living at home (71%) and sedentary (70%). The majority were head and neck cancer patients (22%) who were significantly more active (79%) and lived at home (97%), while those with cerebral palsy (12%) were typically younger (age 31years) but sedentary (94%). Most patients used bolus feeding as their sole feeding method (46%), because it was quick and easy to use, as a top up to oral diet or to mimic meal times. Importantly, oral nutritional supplements (ONS) were used for bolus feeding in 85% of patients, with 51% of these being compact-style ONS (2.4kcal/ml, 125ml). This survey shows that bolus tube feeding is common amongst UK HETF patients, is used by a wide variety of patient groups and can be adapted to meet the needs of a variety of patients, clinical conditions, nutritional requirements and lifestyles.
The study aimed to assess the clinical feasibility of employing an automatic match during cone beam computed tomography (CBCT) imaging using prostatic calcifications within the 95% isodose set as the region of interest.
Materials and methods:
CBCT images were analysed on the 5th fraction in 34 patients evaluating the difference between standard manual soft tissue anatomy matching versus auto calcification matching. An assessment of the clinical feasibility of using prostatic calcifications during matching alongside considering the effect a more automated matching process has been conducted on interobserver variability.
The standard deviation values of the difference between the soft tissue match (baseline) versus automatic calcification matches fluctuated around 1 mm in all three axes for all of the matches carried out. The interobserver variability observed between the two radiographers was 0·055, 0·065 and 0·045 cm in the vertical, longitudinal and lateral axes, respectively.
The clarity of the calcifications on the CBCT images might explain the low interobserver variability displayed by the two matching radiographers. A calcification provides a clear starting point for image matching before commencing a check of volumetric coverage, if the matching process begins in the same place, it can allow for a standardisation of matching technique between radiographers.
Granular flows occur in a wide range of situations of practical interest to industry, in our natural environment and in our everyday lives. This paper focuses on granular flow in the so-called inertial regime, when the rheology is independent of the very large particle stiffness. Such flows have been modelled with the
-rheology, which postulates that the bulk friction coefficient
(i.e. the ratio of the shear stress to the pressure) and the solids volume fraction
are functions of the inertial number
only. Although the
-rheology has been validated in steady state against both experiments and discrete particle simulations in several different geometries, it has recently been shown that this theory is mathematically ill-posed in time-dependent problems. As a direct result, computations using this rheology may blow up exponentially, with a growth rate that tends to infinity as the discretization length tends to zero, as explicitly demonstrated in this paper for the first time. Such catastrophic instability due to ill-posedness is a common issue when developing new mathematical models and implies that either some important physics is missing or the model has not been properly formulated. In this paper an alternative to the
-rheology that does not suffer from such defects is proposed. In the framework of compressible
-dependent rheology (CIDR), new constitutive laws for the inertial regime are introduced; these match the well-established
relations in the steady-state limit and at the same time are well-posed for all deformations and all packing densities. Time-dependent numerical solutions of the resultant equations are performed to demonstrate that the new inertial CIDR model leads to numerical convergence towards physically realistic solutions that are supported by discrete element method simulations.
Infants with prenatally diagnosed CHD are at high risk for adverse outcomes owing to multiple physiologic and psychosocial factors. Lack of immediate physical postnatal contact because of rapid initiation of medical therapy impairs maternal–infant bonding. On the basis of expected physiology, maternal–infant bonding may be safe for select cardiac diagnoses.
This is a single-centre study to assess safety of maternal–infant bonding in prenatal CHD.
In total, 157 fetuses with prenatally diagnosed CHD were reviewed. On the basis of cardiac diagnosis, 91 fetuses (58%) were prenatally approved for bonding and successfully bonded, 38 fetuses (24%) were prenatally approved but deemed not suitable for bonding at delivery, and 28 (18%) were not prenatally approved to bond. There were no complications attributable to bonding. Those who successfully bonded were larger in weight (3.26 versus 2.6 kg, p<0.001) and at later gestation (39 versus 38 weeks, p<0.001). Those unsuccessful at bonding were more likely to have been delivered via Caesarean section (74 versus 49%, p=0.011) and have additional non-cardiac diagnoses (53 versus 29%, p=0.014). There was no significant difference regarding the need for cardiac intervention before hospital discharge. Infants who bonded had shorter hospital (7 versus 26 days, p=0.02) and ICU lengths of stay (5 versus 23 days, p=0.002) and higher survival (98 versus 76%, p<0.001).
Fetal echocardiography combined with a structured bonding programme can permit mothers and infants with select types of CHD to successfully bond before ICU admission and intervention.
Background: Depression and anxiety are the two most frequently studied emotional outcomes of stroke. However, few previous studies have been carried out at a population level or beyond 6 months post stroke. The aim of this study was to describe depression and anxiety across the first year following incident ischemic stroke (IS), and identify predictive factors in a population-based study.
Method: The Hospital Anxiety Depression Scale (HADS) was administered at baseline (within 2 weeks of onset), and again at 1-month, 6-months and 12-months after IS in a sample (N = 365) drawn from a population-based study.
Results: Over 75% of those assessed experienced depression or anxiety symptoms below cut-offs for probable disorder across the year post stroke. Moderate to severe symptoms for anxiety were approximately twice as likely (range 4.1%–10.6%) as compared to depression (range 2.5%–5.0%) at each assessment. The greatest improvement in anxiety occurred within the first month post stroke. In contrast, the greatest reduction in depression occurred between 1- to 6-months post stroke.
Conclusions: Anxiety symptoms in the moderate to severe range were twice as common as depression, and improved over the first month post stroke, whilst depression symptoms persisted for up to 6 months, indicating a need to target these two issues at different points in the recovery process.
Terrestrial gastropods are problematical for radiocarbon (14C) measurement because they tend to incorporate carbon from ancient sources as a result of their dietary behavior. The 14C ecology of the pulmonate land snail, Helix melanostoma in Cyrenaica, northeastern Libya, was investigated as part of a wider study on the potential of using terrestrial mollusk shell for 14C dating of archaeological deposits. H. melanostoma was selected out of the species available in the region as it has the most predictable 14C ecology and also had a ubiquitous presence within the local archaeology. The ecological observations indicate that H. melanostoma has a very homogenous 14C ecology with consistent variations in F14C across sample sites controlled by availability of dietary vegetation. The majority of dated specimens from non-urbanized sample locations have only a small old-carbon effect, weighted mean of 476±48 14C yr, with between ~1% and 9% of dietary F14C from non-organic carbonate sources. Observed instabilities in the 14C ecology can all be attributed to the results of intense human activity not present before the Roman Period. Therefore, H. melanostoma and species with similar ecological behavior are suitable for 14C dating of archaeological and geological deposits with the use of a suitable offset.
Last Supper Cave, located in northwestern Nevada, was excavated in the 1960s and 1970s. It contained a rich record of human occupation spanning the Holocene, but many artifacts from the site, including a large basketry collection, remain unstudied. We report the results of our technological analysis and radiocarbon dating of 14 fiber sandals from Last Supper Cave, which include examples of Fort Rock, Multiple Warp, and Spiral Weft types found at other sites in the northwestern Great Basin. Radiocarbon dates on the sandals correspond well with previous dates from Last Supper Cave and suggest that it was visited episodically for over 10 millennia; however, when considered together with the growing list of dates from the site, the sandal dates suggest that Last Supper Cave saw a prolonged hiatus in occupation during the Middle Holocene—a pattern common at other sandal-bearing sites in the northwestern Great Basin.
Rapid weight gain in infancy and low levels of n-3 long chain polyunsaturated fatty acids (LCPUFA) at birth are associated with increased adiposity later in life. The association between placental LCPUFA delivery and weight gain in infancy is poorly understood. We sought to determine the relationships between maternal phenotype, placental fatty acid transporter expression and offspring growth patterns over the first 6 months. Placental tissue and cord blood were collected at term delivery from women with uncomplicated pregnancies. Offspring body composition measurements were recorded 1 day and 6 months after birth. Body mass index (BMI) z-scores were determined using World Health Organization 2006 reference data. Body phenotype patterns were compared among offspring who had an increase in BMI z-score and those who had a decrease. High skinfold thickness at birth and positive change in BMI z-scores during infancy were associated with low neonatal n-3 LCPUFA plasma levels (r=−0.46, P=0.046) and high saturated fatty acids levels (r=0.49, P=0.034). Growth of skinfolds over 6 months of age was associated with placental fatty acid transporter gene expression. Change in BMI z-score in the first 6 months of life correlated with arm muscle area growth, a measure of lean mass (r=0.62, P=0.003), but not with growth in skinfold thickness. Early infancy weight gain was associated with poor plasma LCPUFA status at birth, and fat deposition in infancy was related to changes in placental lipid handling. Thus, neonatal fatty acid profiles may influence the trajectory of infant growth and fat and lean mass deposition.
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.
Background: Neuropsychological deficits occur in over half of the stroke survivors and are associated with the reduced functioning and a decline in quality of life. However, the trajectory of recovery and predictors of neuropsychological outcomes over the first year post stroke are poorly understood.
Method: Neuropsychological performance, assessed using the CNS-Vital signs, was examined at 1 month, 6 months and 12 months after ischaemic stroke (IS) in a sample drawn from a population-based study (N = 198).
Results: While mean scores across neuropsychological domains at each time-point fell in the average range, one in five individuals produced very low-range scores for verbal memory, attention and psychomotor speed. Significant improvements were seen for executive functioning, psychomotor speed and cognitive flexibility within 6 months post stroke, but no gains were noted from 6 to 12 months. Stroke-related neurological deficits and depression at baseline significantly contributed to the prediction of neuropsychological function at 12 month follow-up.
Conclusions: In a significant minority of IS survivors, focal deficits are evident in psychomotor speed, verbal memory, executive functions and attention. Significant improvements in these domains were only evident in the first 6 months post stroke. Initial stroke-related neurological deficits and concurrent depression may be the best predictors of later cognitive functioning.
In light of the successes of the Navier–Stokes equations in the study of fluid flows, similar continuum treatment of granular materials is a long-standing ambition. This is due to their wide-ranging applications in the pharmaceutical and engineering industries as well as to geophysical phenomena such as avalanches and landslides. Historically this has been attempted through modification of the dissipation terms in the momentum balance equations, effectively introducing pressure and strain-rate dependence into the viscosity. Originally, a popular model for this granular viscosity, the Coulomb rheology, proposed rate-independent plastic behaviour scaled by a constant friction coefficient
. Unfortunately, the resultant equations are always ill-posed. Mathematically ill-posed problems suffer from unbounded growth of short-wavelength perturbations, which necessarily leads to grid-dependent numerical results that do not converge as the spatial resolution is enhanced. This is unrealistic as all physical systems are subject to noise and do not blow up catastrophically. It is therefore vital to seek well-posed equations to make realistic predictions. The recent
-rheology is a major step forward, which allows granular flows in chutes and shear cells to be predicted. This is achieved by introducing a dependence on the non-dimensional inertial number
in the friction coefficient
. In this paper it is shown that the
-rheology is well-posed for intermediate values of
, but that it is ill-posed for both high and low inertial numbers. This result is not obvious from casual inspection of the equations, and suggests that additional physics, such as enduring force chains and binary collisions, becomes important in these limits. The theoretical results are validated numerically using two implicit schemes for non-Newtonian flows. In particular, it is shown explicitly that at a given resolution a standard numerical scheme used to compute steady-uniform Bagnold flow is stable in the well-posed region of parameter space, but is unstable to small perturbations, which grow exponentially quickly, in the ill-posed domain.
Resilience is the capacity of individuals to resist mental disorders despite exposure to stress. Little is known about its neural underpinnings. The putative variation of white-matter microstructure with resilience in adolescence, a critical period for brain maturation and onset of high-prevalence mental disorders, has not been assessed by diffusion tensor imaging (DTI). Lower fractional anisotropy (FA) though, has been reported in the corpus callosum (CC), the brain's largest white-matter structure, in psychiatric and stress-related conditions. We hypothesized that higher FA in the CC would characterize stress-resilient adolescents.
Three groups of adolescents recruited from the community were compared: resilient with low risk of mental disorder despite high exposure to lifetime stress (n = 55), at-risk of mental disorder exposed to the same level of stress (n = 68), and controls (n = 123). Personality was assessed by the NEO-Five Factor Inventory (NEO-FFI). Voxelwise statistics of DTI values in CC were obtained using tract-based spatial statistics. Regional projections were identified by probabilistic tractography.
Higher FA values were detected in the anterior CC of resilient compared to both non-resilient and control adolescents. FA values varied according to resilience capacity. Seed regional changes in anterior CC projected onto anterior cingulate and frontal cortex. Neuroticism and three other NEO-FFI factor scores differentiated non-resilient participants from the other two groups.
High FA was detected in resilient adolescents in an anterior CC region projecting to frontal areas subserving cognitive resources. Psychiatric risk was associated with personality characteristics. Resilience in adolescence may be related to white-matter microstructure.
Interpretations of ancient wall-technologies in the Libyan pre-desert are briefly reviewed. The forms, patterns, distributions and geological/geomorphic/hydrologic relationships of walls in a series of study areas are described and interpreted with the aid of a new, non-genetic, ‘wall-technology’ classification. The remarkable hydrological and geomorphic insights of their constructors are clear. Several wall types are shown to have been primarily concerned with functions other than water control, although this aspect is usually dominant. In some cases the location of the walls appears to have been likely to exacerbate the perennial problems of soil erosion and gullying, in others walls appear to have been constructed specifically to control soil erosion. These data have implications for reconstructing past land use and evaluating the degree of success or failure experienced in particular situations.
A fourth season of work was carried out in the Spring of 1984. The centrepiece of the programme was the investigation of the well-preserved farm in the Wadi el-Amud (Lamout). The main farm buildings were excavated, faunal and botanical samples were collected systematically from within and between them, the field systems and sluices were examined in detail and investigations begun on the geomorphological and hydrological context. This report presents the basic description of the archaeological data resulting from excavation and survey; a second report will present the results of the various laboratory studies which were generated by the field work.
The sedimentological properties of samples collected from exposures in wadi floors are reported. These studies emphasise the natural variability of erosional and depositional processes in this environment. Some of the sedimentological changes observed appear to be of archaeological significance. They indicate that in the recent geological past, either increased flooding occurring as a result of natural environmental fluctuations, or irrigation practice, has caused the elevation of saline groundwaters in the wadi floor sediments to levels which might have had deleterious effects on the contemporary agricultural system. Sites at the margins of the wadis are more sensitive to such changes than those more centrally located on the wadi floor. No evidence for significant climatic change at the times of the extensive Romano-Libyan occupation of the pre-desert region has been detected. There is, however, evidence of much wetter periods in the more distant past, which have left a legacy of mature soils on the basalt plateaus, which may have been extensively used in the Romano-Libyan period.
Aortic arch obstruction can be evaluated by catheter peak-to-peak gradient or by Doppler peak instantaneous pressure gradient. Previous studies have shown moderate correlation in discrete coarctation, but few have assessed correlation in patients with more complex aortic reconstruction.
We carried out retrospective comparison of cardiac catheterisations and pre- and post-catheterisation echocardiograms in 60 patients with native/recurrent coarctation or aortic reconstruction. Aortic arch obstruction was defined as peak-to-peak gradient ⩾25 mmHg in patients with native/recurrent coarctation and ⩾10 mmHg in aortic reconstruction.
Diastolic continuation of flow was not associated with aortic arch obstruction in either group. Doppler peak instantaneous pressure gradient, with and without the expanded Bernoulli equation, weakly correlated with peak-to-peak gradient even in patients with a normal cardiac index (r=0.36, p=0.016, and r=0.49, p=0.001, respectively). Receiver operating characteristic curve analysis identified an area under the curve of 0.61 for patients with all types of obstruction, with a cut-off point of 45 mmHg correctly classifying 64% of patients with arch obstruction (sensitivity 39%, specificity 89%). In patients with aortic arch reconstruction who had a cardiac index ⩾3 L/min/m2, a cut-off point of 23 mmHg correctly classified 69% of patients (71% sensitivity, 50% specificity) with an area under the curve of 0.82.
The non-invasive assessment of aortic obstruction remains challenging. The greatest correlation of Doppler indices was noted in patients with aortic reconstruction and a normal cardiac index.