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The turbulence behaviour of current-dominated pulsating flows has been investigated. Direct numerical simulations have been carried out for Stokes lengths over a range of $l_s^+=5\unicode{x2013}26$, and amplitudes spanning 90 % of the current-dominated regime, about a mean flow of $\overline {Re}=6275$. The results show that the turbulence response in intermediate and low-frequency pulsations is governed by a multistage turbulent–turbulent transition process, which bears a strong similarity to the multistage response of non-periodic acceleration. During the early acceleration period, the flow enters a pretransition stage, in which a new laminar perturbation boundary layer forms at the wall, and the streamwise velocity streaks are stretched. If the low-speed streaks destabilise prior to the deceleration period, then the flow enters a transition stage in which the perturbation boundary layer undergoes a bypass-like transition process. A unique feature of pulsating flows is the ongoing mechanism of turbulence decay, which initiates during the deceleration period and constitutes the main transient turbulence mechanism for much of the cycle. For high-frequency pulsations, the perturbation boundary layer fails to reach the pretransition stage prior to the deceleration period. Instead, the flow alternates between two inertial stages which are characterised by two layers of amplified viscous force; one growing at the wall, and one detached and moving towards the core.
Previous reports indicate bone deficits in patients with Fontan circulation. However, the consequences of these deficits on bone strength and when these changes occur are unclear.
Aim:
To compare the tibial bone strength-strain index between young patients (6–19 years) with Fontan circulation and age- and sex-matched controls, and to determine strength-strain-index in subgroups of children (6–12 years) and adolescents (13–19 years) versus controls.
Method:
The tibia was examined with peripheral quantitative CT. Based on the assessed data, bone strength-strain index was calculated in the lateral and anterior-posterior directions.
Results:
Twenty patients with Fontan and twenty controls (mean age 13.0 ± 4.4 years; 50% females) were examined. Patients had a lower strength-strain index in the lateral direction compared to controls (808.4 ± 416.8mm3 versus 1162.5 ± 552.1mm3, p = 0.043). Subgroup analyses showed no differences regarding strength-strain index in children (6–12 years) with Fontan circulation compared to controls. However, the adolescents (13–19 years) with Fontan circulation had lower strength-strain indexes in both the lateral and anterior-posterior directions compared to controls (1041.4 ± 299.8mm3 versus 1596.4 ± 239.6mm3, p < 0.001, and 771.7 ± 192.4mm3 versus 1084.9 ± 215.0mm3, p = 0.004). When adjusted for height, there were differences between patients (6–19 years) and controls in strength-strain indexes in both the lateral and anterior-posterior directions. In subgroup analyses, the results remained robust.
Conclusion:
Young patients (6–19 years) with Fontan circulation have a lower strength-strain index in the tibia compared to controls. Subgroup analyses show that this deficit is mainly driven by the differences in adolescents (13–19 years), which might suggest that bone strength decreases with age.
This study investigates the dynamics of fingering convection on scales much smaller than the typical size of individual salt fingers. On such scales, salinity patterns exhibit the spontaneous emergence of sharp fronts induced by finger-scale strain. In contrast, velocity and temperature fields are largely devoid of sub-microscale variability, which is attributed to the rapid molecular dissipation of heat and momentum. The presence of fine salinity structures fundamentally limits the efficiency of direct numerical simulations (DNS) of double-diffusive processes. In the oceanographic context, the computational cost of resolving sub-microscale salinity features exceeds that of temperature-only DNS by up to four orders of magnitude, severely restricting the types of double-diffusive systems that can be studied numerically. To address this complication, we introduce the sub-microscale filtering (SMF) algorithm, which resolves temperature and velocity while parameterizing the sub-microscale dynamics of salinity. The proposed closure draws inspiration from the Smagorinsky scheme, which represents unresolved processes by the downgradient strain-dependent momentum flux. The SMF model is successfully validated through fully resolved simulations.
Dysphagia is common in children with CHDs, resulting in multiple stressors for their caregivers including having a child with a serious medical condition and coping with their child’s feeding needs. However, relatively little is known about caregivers’ perceptions and experiences of the burden of care and support needs for their child with a CHD and dysphagia in low-middle income contexts. This qualitative study investigated the burden of care and support needs identified by parents of children with CHDs and dysphagia in a single centre in South Africa. Semi-structured interviews took place in a tertiary hospital with seven mothers of children with CHDs and dysphagia, followed by content analysis. Participants described four main impacts of their child’s condition, which included worry, the burden of caregiving, emotional responses, and acceptance and coping. The participants were well-supported by speech-language therapists and dieticians, but suggestions for additional support included support groups and using mobile messaging apps for communication with peers and professionals. The study has important implications for understanding challenges faced by caregivers of children with complex needs in low-middle income settings and will be useful to inform and improve holistic healthcare practice for families of children with CHDs and dysphagia.
The present paper is concerned with the infimum of the norm of potentials for Sturm–Liouville eigenvalue problems with Dirichlet boundary condition such that the first two eigenvalues are known. The explicit quantity of the infimum is given by the two eigenvalues.
This article explores the remaking of administrative law review in South Africa since the introduction of constitutional democracy in 1994. It characterizes the construction of the constitutional and legislative framework, as well as the courts’ interpretation of that framework, as the first phase of the remaking. The second phase encompasses the courts’ recognition of a constitutional principle of legality based on the rule of law, and their swift development of the content of this principle. This judicial creativity has resulted in an elaborate avenue to review, parallel to the Promotion of Administrative Justice Act 3 of 2000, and has caused problems of rivalry and avoidance. The article identifies and discusses some of the more significant implications of each of these phases of reconstruction. It also proposes corrective measures likely to advance the coherence and effectiveness of judicial review and discourage the adoption of a doctrine of non-justiciability.
Handgrip strength is a crucial indicator of upper extremity muscular strength and is vital for monitoring disorders like cardiac diseases that restrict a patient’s physical activity and result in muscle atrophy. The aim of our study was to evaluate whether muscle strength loss is present in patients with pulmonary hypertension and whether this test can be an alternative to 6-minute walk test.
Materials and methods:
The study included 39 healthy children who were admitted to the outpatient clinic and 16 children with a diagnosis of pulmonary hypertension who were being followed in our centre. We assessed the differences in upper extremity handgrip strength using the Jamar Hydraulic Hand Dynamometer device among both healthy children and those diagnosed with pulmonary hypertension. Moreover, we compared the handgrip strength of pulmonary hypertension patients with significant prognostic indicators such as NYHA class, 6-minute walk test, and pro-brain natriuretic peptide.
Results:
The mean dominant handgrip strength was 20.8 ± 12 kg in the patient group and 21.6 ± 12.4 kg in the control group (p = 0.970). Handgrip strength was shown to be negatively connected with pro-brain natriuretic peptide (r = −0.565, p = 0.023) and positively correlated with 6-minute walk test (r = 0.586, p = 0.022) during the patient group evaluation.
Conclusion:
Six-minute walk test needs a customised physical area (30 m of a straight hallway) and trained personnel for applying the test. The handgrip strength test, a different muscle strength indicator, can be used to more clearly and simply indicate the decline in patients’ ability for effort. Additionally, it was found in our study that handgrip strength decreased as pro-brain natriuretic peptide levels rose, a crucial measure in the monitoring of pulmonary hypertension.
For a real number $0<\epsilon <1/3$, we show that the anti-canonical volume of an $\epsilon $-klt Fano $3$-fold is at most $3,200/\epsilon ^4$, and the order $O(1/\epsilon ^4)$ is sharp.
The eighteenth century is often thought of as an important era for the secularization of British philosophy. One dimension of this secularization involves philosophers developing theories that, while not explicitly rejecting God, are less reliant on claims about God for their intelligibility and plausibility. A comparison of Adam Smith with his teacher, Francis Hutcheson, reveals an underappreciated facet of this process. Hutcheson portrayed God as an impartial legislator and used this metaphor to clarify contested moral rules in a way that would make little sense if God did not exist. In contrast, Smith's impartial spectator does not require belief in a God who is the author of the moral law in order to determine the correct interpretation of contested moral principles. By pursuing this alternative conception of impartiality, Smith developed a theory that was, in this respect, less reliant on religious premises than Hutcheson's had been.
La qualité des soins apportés aux personnes vivant avec la maladie d’Alzheimer (MA) dépend en partie de la capacité des professionnels à déterminer le degré de conscience de la maladie chez les patients. La présente recherche s’est intéressée aux représentations des soignants concernant la conscience des troubles chez les résidents d’établissements de soins de longue durée présentant un diagnostic de MA. Le pouvoir prédicteur de l’anosognosie sur le fardeau soignant a également été examiné. L’anosognosie des troubles de la construction (r = 0,40, p = 0,0164) et de l’initiation (r = 0,32, p = 0,052) était corrélée au fardeau soignant. Les professionnels se représentaient les résidents comme ayant une conscience altérée de leurs capacités, même en l’absence d’anosognosie. Les scores réels d’anosognosie ne prédisaient pas les estimations soignantes, hormis le score global sous forme de tendance (χ2 = 3,38, p = 0,066). Les soignants surestimaient pourtant les performances cognitives des résidents, telles que mesurées au moyen du protocole Misawareness (prédictions aidants/performances réelles : DC = 12,32, p < 0,0001).
As regional chronologies become better defined, we are better able to track large-scale population movements and related cultural change. A dataset of 156 radiocarbon dates from the Middle Cumberland Region (MCR), evaluated with 199 more dates from the Ridge and Valley portions of northern Georgia and East Tennessee, enable modeling of population movements from the Central Mississippi Valley into the MCR, as well as subsequent movements and effects in the Ridge and Valley between AD 1200 and 1450. The dissolution of Cahokia is of particular interest, because the MCR falls geographically between the American Bottom and the Ridge and Valley province. This large-scale chronological perspective places key events in this part of the Southeast and Midwest into a unified historical framework that increases our understanding of the timing of cultural events. A related goal is to sort out possible external events and influences that may have affected this large region. This study makes apparent the relationships between cultural events and natural events, such as the drought sequences reported for the Central Mississippi Valley and beyond.