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The present study investigates streamwise ($\overline {u^2}$) energy-transfer mechanisms in the inner and outer regions of turbulent boundary layers (TBLs). Particular focus is placed on the $\overline {u^2}$ production, its inter-component and wall-normal transport as well as dissipation, all of which become statistically significant in the outer region with increasing friction Reynolds number ($Re_{\tau }$). These properties are analysed using published data sets of zero, weak and moderately strong adverse-pressure-gradient (APG) TBLs across a decade of $Re_{\tau }$, revealing similarity in energy-transfer pathways for all these TBLs. It is found that both the inner and outer peaks of $\overline {u^2}$ are always associated with local maxima in the $\overline {u^2}$ production and its inter-component transport, and the regions below/above each of these peaks are always dominated by wall-ward/away-from-wall transport of $\overline {u^2}$, thereby classifying the $\overline {u^2}$ profiles into four distinct regimes. This classification reveals existence of phenomenologically similar energy-transfer mechanisms in the ‘inner’ and ‘outer’ regions of moderately strong APG TBLs, which meet at an intermediate location coinciding with the minimum in $\overline {u^2}$ profiles. Conditional averaging suggests existence of similar phenomena even in low $Re_{\tau }$ canonical and/or weak APG TBLs, albeit with the outer-region mechanisms weaker than those in the inner region. This explains the absence of their $\overline {u^2}$ outer peak and the dominance of $\overline {u^2}$ wall-normal transport away from the wall, which potentially originates from the inner region. Given that the wall-ward/away-from-wall transport of $\overline {u^2}$ is governed by the $Q_4$(sweeps)/$Q_2$(ejections) quadrants of the Reynolds shear stress, it is argued that the emergence of the $\overline {u^2}$ outer peak corresponds with the statistical dominance of $Q_4$ events in the outer region. Besides unravelling the dynamical significance of $Q_2$ and $Q_4$ events in the outer region of TBLs, the present analysis also proposes new phenomenological arguments for testing on canonical wall-turbulence data at very high $Re_{\tau }$.
During the military regime in Brazil (1964–1985), enrollment ratios in primary education grew substantially in the first decade under dictatorship, but stagnated in the mid-1970s. This paper shows that education spending might depend on the levels of centralisation in tax matters. Using panel data regressions and qualitative evidence, we argue that a massive big push industrialisation programme increased the pressure on external accounts, leading the government to intensify an export incentive policy based on tax subsidies that decreased the income of subnational governments. As a result, the capacity of funding mass education was compromised in the second half of the 1970s.
We conducted an axisymmetric numerical study of drop impact on a thin film of the same liquid in order to generate maps identifying the fluid elements in the drop and film that are transferred to the corolla during impact. We find that mass contribution from the drop comes from a surprisingly thin surface layer on the drop, and furthermore, that the shape of this layer in the drop and the film scales with film thickness, not the Weber number and Reynolds number as one might expect. The maps could be used to tailor drop composition for applications such as coatings or encapsulations.
Rotating Rayleigh–Bénard convection denotes the convection between a warm plate and a cold plate in a rotating environment. It is a classic model for understanding convective vortices in the atmosphere and ocean. The influence of background rotation on fluid inertia breaks the symmetry between cyclones and anticyclones. Such a symmetry breaking could be represented by vorticity skewness, which still lacks a systematic theory. Rapidly rotating convection with stress-free boundaries and unit Prandtl number is a convenient starting point. The investigation starts from the convective onset stage, where the vortices grow stationarily. Asymptotic analysis shows that the volumetric vorticity skewness $S$ is produced by the interaction between the $n=0,1$ and $n=1,2$ vertical eigenmodes. The $n=0$ (barotropic) mode contributes positively to $S$ mainly by stretching the vertical relative vorticity, an ageostrophic effect. The $n=2$ mode makes a minor negative contribution to $S$ by preferentially intensifying the outflow over the inflow, a non-hydrostatic effect. The theory predicts $S$ to be proportional to the global Rossby number defined with the volumetric standard deviation of vorticity, ${Ro_g}$. The proportional factor does not depend on the Rayleigh and Ekman numbers, agreeing with direct numerical simulations. Then the system enters the equilibrium stage. The stretching of vertical vorticity still contributes to $S$ dominantly. At ${Ro_g}\gtrsim 0.5$, the emergent unsteady flow significantly suppresses the asymmetry between the inflow and outflow strength, and weakens its influence on $S$.
We determine the order of the k-core in a large class of dense graph sequences. Let $G_n$ be a sequence of undirected, n-vertex graphs with edge weights $\{a^n_{i,j}\}_{i,j \in [n]}$ that converges to a graphon $W\colon[0,1]^2 \to [0,+\infty)$ in the cut metric. Keeping an edge (i,j) of $G_n$ with probability ${a^n_{i,j}}/{n}$ independently, we obtain a sequence of random graphs $G_n({1}/{n})$. Using a branching process and the theory of dense graph limits, under mild assumptions we obtain the order of the k-core of random graphs $G_n({1}/{n})$. Our result can also be used to obtain the threshold of appearance of a k-core of order n.
After 78 years of democracy, Italy continues to grapple with its recent past in the political, social, and cultural spheres. Its experience of fascism under Mussolini, its dual participation in the Second World War, and the continuous and still existent connections between the ideological factions of the 1930s–1940s and now render the country a rich case for the study of public history and memory. The specificity of these characteristics has often made Italian history and memory look like an outlier, shaped by circumstances difficult to compare with those of other countries'. This paper argues that contemporary Italian memory politics are in reality a valuable source of information about the kind of mnemonic discourses that may arise in other (Western) European countries, given the increasingly polarised and populist European landscape. Our study of discourses put forwarded by the post-fascist party Fratelli d'Italia reveals a set of mnemonic tools with which they successfully banalise fascism and chip at Italian public discourse slowly but surely. The comparison between this discourse and that of VOX and AfD in Spain and Germany, respectively, shows that these tools, ranging from nativism to policy (de)legitimation linked to fascist imagery, has started to transfer to other countries' political strategies.
We settle the noninner automorphism conjecture for finite p-groups ($p> 2$) with certain conditions. Also, we give an elementary and short proof of the main result of Ghoraishi [‘On noninner automorphisms of finite nonabelian p-groups’, Bull. Aust. Math. Soc.89(2) (2014) 202–209].
Previous studies have indicated associations between maternal mental disorders and adverse birth outcomes; however, these studies mainly focus on certain types of mental disorders, rather than the whole spectrum.
Aims
We aimed to conduct a broad study examining all maternal mental disorder types and adverse neonatal outcomes which is needed to provide a more complete understanding of the associations.
Method
We included 1 132 757 liveborn singletons born between 1997 and 2015 in Denmark. We compared children of mothers with a past (>2 years prior to conception; n = 48 646), recent (2 years prior to conception and during pregnancy; n = 15 899) or persistent (both past and recent; n = 10 905) diagnosis of any mental disorder, with children of mothers with no mental disorder diagnosis before the index delivery (n = 1 057 307). We also considered different types of mental disorders. We calculated odds ratios and 95% CIs of low birthweight, preterm birth, small for gestational age, low Apgar score, Caesarean delivery and neonatal death.
Results
Odds ratios for children exposed to past, recent and persistent maternal mental disorders suggested an increased risk for almost all adverse neonatal outcomes. Estimates were highest for children in the ‘persistent’ group for all outcomes, with the exception of the association between persistent maternal mental disorders and neonatal death (odds ratio 0.96, 0.62–1.48).
Conclusions
Our study provides evidence for increased risk of multiple adverse neonatal outcomes among children of mothers with mental disorders, highlighting the need for close monitoring and support for women with mental disorders.
Let p be a prime number. Let $n\geq 2$ be an integer given by $n = p^{m_1} + p^{m_2} + \cdots + p^{m_r}$, where $0\leq m_1 < m_2 < \cdots < m_r$ are integers. Let $a_0, a_1, \ldots , a_{n-1}$ be integers not divisible by p. Let $K = \mathbb Q(\theta )$ be an algebraic number field with $\theta \in {\mathbb C}$ a root of an irreducible polynomial $f(x) = \sum _{i=0}^{n-1}a_i{x^i}/{i!} + {x^n}/{n!}$ over the field $\mathbb Q$ of rationals. We prove that p divides the common index divisor of K if and only if $r>p$. In particular, if $r>p$, then K is always nonmonogenic. As an application, we show that if $n \geq 3$ is an odd integer such that $n-1\neq 2^s$ for $s\in {\mathbb Z}$ and K is a number field generated by a root of a truncated exponential Taylor polynomial of degree n, then K is always nonmonogenic.
Warren Nutter’s work as director of the National Bureau of Economic Research’s (NBER) Soviet growth project is his best-known contribution to economics and public affairs. Many histories of Sovietology note the oddity of Nutter’s selection as project director, given his apparent lack of prior experience studying the Soviet Union. This paper provides new context for Nutter’s selection to lead the NBER effort. From 1951 to 1952 Nutter was the acting chief of the Economic Capabilities Branch of the CIA’s Office of Research and Reports (ORR), and chairman of the Economic Analysis Subcommittee of the interagency Economic Intelligence Committee. In this capacity he managed at least three major research efforts, including an input-output analysis of the Soviet Union and contributions to two national intelligence estimates. Nutter may have been proposed as director of the NBER project by Robert Amory, the Deputy Director of Intelligence, in 1953. Nutter’s research for the CIA cultivated new analytic capacities for the agency and provided a foundation for his own work on the Soviet Union.
Obsessive-compulsive disorder (OCD) and eating disorders (ED) are compulsive disorders with overlapping symptoms. However, weight loss and over-exercise causing secondary medical complications are rarely seen in OCD. We report the case of a 15-year-old male who presented with atypical symptoms of OCD leading to severe medical compromise. Covid-19 related team sport restrictions led to compulsive exercise associated with intrusive thoughts. The onset of stress fractures limited exercise ability, prompting compensatory food restriction. Bradycardia, hypothermia and hypoglycaemia resulted from severe malnourishment and weight loss in the context of OCD. His weight was 85.8% of ideal body weight on admission, reflective of a weight 10–15 kg lower than his premorbid weight. During admission, he developed exercise-induced rhabdomyolysis with significantly elevated creatinine kinase and required intensive care unit treatment. Psychotropic medication included lamotrigine, olanzapine and high dose fluoxetine alongside cognitive-behavioural therapy. Medical stabilisation and weight restoration allowed discharge to an outpatient Child and Adolescent Mental Health Service. This atypical case of OCD highlights the potentially life-threatening risks associated with excessive exercise and malnutrition. This paper highlights the complexities of treatment in a patient who cannot adhere to bed rest and the differential diagnoses of anorexia nervosa, orthorexia nervosa and exercise addiction.
Horses began to feature prominently in funerary contexts in southern Siberia in the mid-second millennium BC, yet little is known about the use of these animals prior to the emergence of vibrant horse-riding groups in the first millennium BC. Here, the authors present the results of excavations at the late-ninth-century BC tomb of Tunnug 1 in Tuva, where the deposition of the remains of at least 18 horses and one human is reminiscent of sacrificial spectral riders described in fifth-century Scythian funerary rituals by Herodotus. The discovery of items of tack further reveals connections to the earliest horse cultures of Mongolia.
An ostium secundum atrial septal defect (ASD) is a CHD that can be treated percutaneously since 1974, mostly cases with only one main defect. In cases with fenestrations close to the main defect, a single occluder can be used for treatment because the discs extend beyond the waist of the device. In some cases where the defects are far from each other, they may require either more than one device or surgical closure. We present two patients in whom we observed fenestrations far from the primary defect. Initially, the main ASDs were closed with an ASD occluder, and then the fenestrations were closed with a patent ductus arteriosus (PDA) coil, resulting in complete closure of both defects. This shows that closing small fenestrations that are far away from the primary interatrial defect without rims and using other devices instead, such as a PDA coil, is feasible and can avoid the need for an open-heart surgical procedure; moreover, it is important to note that leaving these fenestrations open can have the same physiology as a patent foramen oval.
We provide decadal estimates of GDP per capita for the Russian Empire from the 1690s to the 1880s, making it possible for the first time to compare the economic performance of one of the world’s largest economies with other countries. Significant Russian economic growth before the 1760s resulted in catching-up on northwest Europe, but this was followed by a period of negative growth between the 1760s and 1800s and stagnation from the 1800s to the 1880s, leaving late-nineteenth century Russia further behind the West than at the beginning of the eighteenth century.
Healthcare-associated infections (HAIs) pose significant challenges to healthcare systems worldwide. Epidemiological data are essential for effective HAI control; however, comprehensive information on HAIs in Japanese hospitals is limited. This study aimed to provide an overview of HAIs in Japanese hospitals.
Methods:
A multicenter point-prevalence survey (PPS) was conducted in 27 hospitals across the Aichi Prefecture between February and July 2020. This study encompassed diverse hospital types, including community, university, and specialized hospitals. Information on the demographic data of the patients, underlying conditions, devices, HAIs, and causative organisms was collected.
Results:
A total of 10,199 patients (male: 5,460) were included in this study. The median age of the patients was 73 (interquartile range [IQR]: 56–82) years, and the median length of hospital stay was 10 (IQR: 4–22) days. HAIs were present in 6.6% of patients, with pneumonia (1.83%), urinary tract infection (1.09%), and surgical site infection (SSI) (0.87%) being the most common. The prevalence of device-associated HAIs was 0.91%. Staphylococcus aureus (17.3%), Escherichia coli (17.1%), and Klebsiella pneumoniae (7.2%) were the primary pathogens in 433 organisms; 29.6% of the Enterobacterales identified showed resistance to third-generation cephalosporins. Pneumonia was the most prevalent HAI in small-to-large hospitals (1.69%–2.34%) and SSI, in extra-large hospitals (over 800 beds, 1.37%).
Conclusions:
This study offers vital insights into the epidemiology of HAIs in hospitals in Japan. These findings underscore the need for national-level PPSs to capture broader epidemiological trends, particularly regarding healthcare challenges post-COVID-19.
Society of Thoracic Surgeons Congenital Heart Surgery Database is the largest congenital heart surgery database worldwide but does not provide information beyond primary episode of care. Linkage to hospital electronic health records would capture complications and comorbidities along with long-term outcomes for patients with CHD surgeries. The current study explores linkage success between Society of Thoracic Surgeons Congenital Heart Surgery Database and electronic health record data in North Carolina and Georgia.
Methods:
The Society of Thoracic Surgeons Congenital Heart Surgery Database was linked to hospital electronic health records from four North Carolina congenital heart surgery using indirect identifiers like date of birth, sex, admission, and discharge dates, from 2008 to 2013. Indirect linkage was performed at the admissions level and compared to two other linkages using a “direct identifier,” medical record number: (1) linkage between Society of Thoracic Surgeons Congenital Heart Surgery Database and electronic health records from a subset of patients from one North Carolina institution and (2) linkage between Society of Thoracic Surgeons data from two Georgia facilities and Georgia’s CHD repository, which also uses direct identifiers for linkage.
Results:
Indirect identifiers successfully linked 79% (3692/4685) of Society of Thoracic Surgeons Congenital Heart Surgery Database admissions across four North Carolina hospitals. Direct linkage techniques successfully matched Society of Thoracic Surgeons Congenital Heart Surgery Database to 90.2% of electronic health records from the North Carolina subsample. Linkage between Society of Thoracic Surgeons and Georgia’s CHD repository was 99.5% (7,544/7,585).
Conclusions:
Linkage methodology was successfully demonstrated between surgical data and hospital-based electronic health records in North Carolina and Georgia, uniting granular procedural details with clinical, developmental, and economic data. Indirect identifiers linked most patients, consistent with similar linkages in adult populations. Future directions include applying these linkage techniques with other data sources and exploring long-term outcomes in linked populations.