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We examined demographic, clinical, and psychological characteristics of a large cohort (n = 368) of adults with dissociative seizures (DS) recruited to the CODES randomised controlled trial (RCT) and explored differences associated with age at onset of DS, gender, and DS semiology.
Prior to randomisation within the CODES RCT, we collected demographic and clinical data on 368 participants. We assessed psychiatric comorbidity using the Mini-International Neuropsychiatric Interview (M.I.N.I.) and a screening measure of personality disorder and measured anxiety, depression, psychological distress, somatic symptom burden, emotional expression, functional impact of DS, avoidance behaviour, and quality of life. We undertook comparisons based on reported age at DS onset (<40 v. ⩾40), gender (male v. female), and DS semiology (predominantly hyperkinetic v. hypokinetic).
Our cohort was predominantly female (72%) and characterised by high levels of socio-economic deprivation. Two-thirds had predominantly hyperkinetic DS. Of the total, 69% had ⩾1 comorbid M.I.N.I. diagnosis (median number = 2), with agoraphobia being the most common concurrent diagnosis. Clinical levels of distress were reported by 86% and characteristics associated with maladaptive personality traits by 60%. Moderate-to-severe functional impairment, high levels of somatic symptoms, and impaired quality of life were also reported. Women had a younger age at DS onset than men.
Our study highlights the burden of psychopathology and socio-economic deprivation in a large, heterogeneous cohort of patients with DS. The lack of clear differences based on gender, DS semiology and age at onset suggests these factors do not add substantially to the heterogeneity of the cohort.
The time at which the Laurentide Ice Sheet reached its maximum extent and subsequently retreated from its terminal moraine in New Jersey has been constrained by bracketing radiocarbon ages on preglacial and postglacial sediments. Here, we present measurements of in situ produced 10Be and 26Al in 16 quartz-bearing samples collected from bedrock outcrops and glacial erratics just north of the terminal moraine in north-central New Jersey; as such, our ages represent a minimum limit on the timing of ice recession from the moraine. The data set includes field and laboratory replicates, as well as replication of the entire data set five years after initial measurement. We find that recession of the Laurentide Ice Sheet from the terminal moraine in New Jersey began before 25.2±2.1 ka (10Be, n=16, average, 1 standard deviation). This cosmogenic nuclide exposure age is consistent with existing limiting radiocarbon ages in the study area and cosmogenic nuclide exposure ages from the terminal moraine on Martha’s Vineyard ~300 km to the northeast. The age we propose for Laurentide Ice Sheet retreat from the New Jersey terminal position is broadly consistent with regional and global climate records of the last glacial maximum termination and records of fluvial incision.
Frailty is a state of decreased physical functioning and a significant complication of ageing. We examined frailty, energy and macronutrient intake, biomarkers of nutritional status and food insufficiency in US older adult (age ≥ 60 years) participants of the Third National Health and Nutrition Examination Survey (n 4731). Frailty was defined as meeting ≥ 2 and pre-frailty as meeting one of the following four-item criteria: (1) slow walking; (2) muscular weakness; (3) exhaustion and (4) low physical activity. Intake was assessed by 24 h dietary recall. Food insufficiency was self-reported as ‘sometimes’ or ‘often’ not having enough food to eat. Analyses were adjusted for sex, race, age, smoking, education, income, BMI, other co-morbid conditions and complex survey design. Prevalence of frailty was highest among people who were obese (20·8 %), followed by overweight (18·4 %), normal weight (16·1 %) and lowest among people who were underweight (13·8 %). Independent of BMI, daily energy intake was lowest in people who were frail, followed by pre-frail and highest in people who were not frail (6648 (se 130), 6966 (se 79) and 7280 (se 84) kJ, respectively, P< 0·01). Energy-adjusted macronutrient intakes were similar in people with and without frailty. Frail (adjusted OR (AOR) 4·7; 95 % CI 1·7, 12·7) and pre-frail (AOR 2·1; 95 % CI 0·8, 5·8) people were more likely to report being food insufficient than not frail people. Serum albumin, carotenoids and Se levels were lower in frail adults than not frail adults. Research is needed on targeted interventions to improve nutritional status and food insufficiency among frail older adults, while not necessarily increasing BMI.
Infection surveillance definitions for long-term care facilities (ie, the McGeer Criteria) have not been updated since 1991. An expert consensus panel modified these definitions on the basis of a structured review of the literature. Significant changes were made to the criteria defining urinary tract and respiratory tract infections. New definitions were added for norovirus gastroenteritis and Clostridum difficile infections.
Permian colonial corals from Artinskian to Kungurian strata in the Conglomerate Mesa area, Inyo Mountains, east-central California, include five new species, one of which is assigned to a new genus. The new taxa are: Malpaisia maceyi n. gen. and n. sp., Pararachnastraea bellula n. sp., P. delicata n. sp., P. owensensis n. sp., and Cordillerastraea inyoensis n. sp. These species, several of which compare most closely with other Artinskian and Kungurian species from eastern Nevada and northern Mexico, represent three distinct stocks that differentiated on an isolated submarine uplift offshore from the main part of the Cordilleran carbonate shelf.
Groups usually appear in physics as symmetries of the system or model we are studying. Often the symmetry operation involves a linear transformation, and this naturally leads to the idea of finding sets of matrices having the same multiplication table as the group. These sets are called representations of the group. Given a group, we endeavour to find and classify all possible representations.
We begin with a rapid review of basic group theory.
A group G is a set with a binary operation that assigns to each ordered pair (g1, g2) of elements a third element, g3, usually written with multiplicative notation as g3 = g1g2. The binary operation, or product, obeys the following rules:
(i) Associativity: g1(g2g3) = (g1g2)g3.
(ii) Existence of an identity: there is an element e ∈ G such that eg = g for all g ∈ G.
(iii) Existence of an inverse: for each g ∈ G there is an element g–1 such that g–1g = e.
From these axioms there follow some conclusions that are so basic that they are often included in the axioms themselves, but since they are not independent, we state them as corollaries.
We begin our tour of useful mathematics with what is called the calculus of variations. Many physics problems can be formulated in the language of this calculus, and once they are there are useful tools to hand. In the text and associated exercises we will meet some of the equations whose solution will occupy us for much of our journey.
What is it good for?
The classical problems that motivated the creators of the calculus of variations include:
(i) Dido's problem: In Virgil's Aeneid, Queen Dido of Carthage must find the largest area that can be enclosed by a curve (a strip of bull's hide) of fixed length.
(ii) Plateau's problem: Find the surface of minimum area for a given set of bounding curves. A soap film on a wire frame will adopt this minimal-area configuration.
(iii) Johann Bernoulli's brachistochrone: A bead slides down a curve with fixed ends. Assuming that the total energy ½ mv2 + V(x) is constant, find the curve that gives the most rapid descent.
(iv) Catenary: Find the form of a hanging heavy chain of fixed length by minimizing its potential energy.
These problems all involve finding maxima or minima, and hence equating some sort of derivative to zero. In the next section we define this derivative, and show how to compute it.
In variational problems we are provided with an expression J[y] that “eats” whole functions y(x) and returns a single number. Such objects are called functionals to distinguish them from ordinary functions.
Topology is the study of the consequences of continuity. We all know that a continuous real function defined on a connected interval and positive at one point and negative at another must take the value zero at some point between. This fact seems obvious – although a course of real analysis will convince you of the need for a proof. A less obvious fact, but one that follows from the previous one, is that a continuous function defined on the unit circle must posses two diametrically opposite points at which it takes the same value. To see that this is so, consider f (θ + π) – f (θ). This difference (if not initially zero, in which case there is nothing further to prove) changes sign as θ is advanced through π, because the two terms exchange roles. It was therefore zero somewhere. This observation has practical application in daily life: our local coffee shop contains four-legged tables that wobble because the floor is not level. They are round tables, however, and because they possess no misguided levelling screws all four legs have the same length. We are therefore guaranteed that by rotating the table about its centre through an angle of less than π/2 we will find a stable location. A ninety-degree rotation interchanges the pair of legs that are both on the ground with the pair that are rocking, and at the change-over point all four legs must be simultaneously on the ground.
Similar effects with a practical significance for physics appear when we try to extend our vector and tensor calculus from a local region to an entire manifold.