486 research outputs found
Weight cycling in treatment-seeking obese persons: data from the QUOVADIS study
OBJECTIVE: To determine parameters of weight history useful for the assessment of weight cycling and their association with
psychological distress and binge eating.
DESIGN: Cross-sectional.
SUBJECTS: A total of 1889 treatment-seeking obese subjects, enrolled by 25 Italian centers (78% female subject), aged 20–65 y
(median 45); 1691 reported previous efforts to lose weight (median age of first dieting, 30 y).
MEASUREMENTS: The number of yearly attempts to lose weight, weight gain since age 20 y, cumulative weight loss and
gain were checked by a predefined structured interview. Psychological distress was tested by means of Symptom Check-List 90
(SCL-90), Binge Eating Scale (BES) and Three Factor Eating Questionnaire (TFEQ).
RESULTS: Differences in anthropometric, clinical and psychological parameters were observed in relation to previous attempts
to lose weight. Patients in the upper quartile of parameters of weight history were considered weight cyclers. In multivariate
logistic regression analysis, after correction for age, sex and BMI, a high BES score was the only factor systematically associated
with a high frequency of dieting (OR, 1.70; 95% confidence interval, 1.22–2.36; P¼0.022), with higher cumulative weight loss
(1.42; 1.12–1.80; P¼0.003) and cumulative weight gain (1.38; 1.06–1.79; P¼0.017). However, the sensitivity, specificity and
positive predictive value of a high BES score were very low to detect cyclers. Weight cycling did not carry a higher risk of
complicating diseases.
CONCLUSIONS: Weight cycling is associated with psychological distress, and binge eating independently increases the risk, but
cannot be used to predict cycling. Also, obese patients who do not experience overeating as a loss of control discontinue
treatment or regain weight following therapy
Validating the Body Uneasiness Test (BUT) in obese patients
OBJECTIVE: To investigate the psychometric properties of the Body
Uneasiness Test (BUT) in a large sample of subjects with obesity seeking treatment. BUT is a
71-item self-report questionnaire in two parts: BUT-A which measures weight phobia, body
image concerns, avoidance, compulsive self-monitoring, detachment and estrangement feelings
towards one’s own body (depersonalization); and BUT-B, which looks at specific worries
about particular body parts or functions. METHODS: We recruited a clinical sample of
1,812 adult subjects (age range 18-65 years, females 1,411, males 401) with obesity (Body
Mass Index, BMI ≥30 kg/m2) and a normal weight (BMI value between 18.5 and 25 kg/m2)
non-clinical sample of 457 adult subjects (females 248, males 209) with an Eating Attitudes
Test-26 (EAT-26) score under the cut-off point 20 (scores ≥20 indicate possible cases of eating
disorders). RESULTS: The exploratory and confirmatory analyses confirmed a structural
five-factor model for BUT-A and an eight-factor model for BUT-B. Internal consistency was
satisfactory. Concurrent validity with Binge Eating Scale (BES) and Three-Factor Eating
Questionnaire (TFEQ) was evaluated. The authors calculated mean values for BUT scores in
adult (18-65 years) patients with obesity, and evaluated the influence of gender, age and BMI.
Females obtained statistically significant higher scores than males in all age groups and in all
classes of obesity; patients with obesity, compared with normal weight subjects, generally
obtained statistically significant higher scores, but few differences could be attributed to the
influence of BMI. CONCLUSION: The BUT can be a valuable multidimensional tool for the
clinical assessment of body uneasiness in obesity; the scores of its sub-scales do not show a
linear correlation with BMI values
Ability of the Chester Step Test to detect functional impairment and mortality risk in people with interstitial lung disease
People with interstitial lung disease (ILD) often experience disabling symptoms, which impairs their functional capacity, further
accelerating disease progression. The 6-minute walk test (6MWT)
has been the most widely used field test to assess functional capacity and to discriminate the mortality risk in people with ILD.
Nevertheless, its application across settings (e.g., patients’
homes) is often limited due to the need of a 30 m corridor. Alternatives to assess functional capacity in these settings have been
emerging, such as the 1-minute sit-to-stand test (1-minSTS) and
the Chester step test (CST). However, the first does not allow
exercise prescription. The CST is a simple and low-cost field test,
which enables exercise prescription and requires minimal physical
space to assess functional capacity. Its suitability to be used as a
first-line screening tool to detect functional capacity impairment
and mortality risk in people with ILD is however unknown. Thus,
the aim of this study was to determine the discriminative ability
of the CST in distinguishing people with ILD with or without functional impairment and low or higher risk of mortality. A retrospective cross-sectional study was conducted with stable (i.e., no history of acute cardiac events, acute exacerbations or other
respiratory complications in the previous month) people with ILD.
The following measures were collected: CST, 6MWT and 1-minSTS.
A receiver operating characteristics (ROC) curve analysis was performed and area under the curve (AUC), sensitivity, specificity and
accuracy were calculated. We determined a threshold for the CST
to identify: i) functional impairment, based on published cut-offs
of the percentage predicted of the 1-minSTS and the 6MWT (both
70% predicted); and, ii) mortality, based on different established
cut-offs of the 6MWT (250, 330 and 350 m). The optimal cut-off
points were identified by the highest Youden index. Eighty-three
people with ILD (65 ± 14 years old; 45 [54.2%] female; FVC 77.7 ±
17.9%predicted; DLCO 50.3 ± 20.7% predicted) were included in
the analysis. The cut-off points of the 1-minSTS (AUC = 0.73; 95%CI
0.63-0.84; 81% sensitivity; 65% specificity; accuracy = 0.72) and
6MWT (AUC = 0.91; 95%CI 0.82-0.99; 88% sensitivity; 83% specificity; accuracy = 0.86) identified a cut-off of 40.5 steps in CST to
detect functional impairment in people with ILD. All cut-offs of
the 6MWT identified a cut-off of 36 steps on the CST (6MWT <
250m: AUC = 0.89; 95% CI 0.80-0.97; 86% sensitivity; 80% specificity; accuracy = 0.80; 6MWT < 330m: AUC = 0.97; 95%CI 0.93-1; 96%
sensitivity; 81% specificity; accuracy = 0.90; 6MWT < 350m: AUC =
0.93; 95%CI 0.86-1; 98% sensitivity; 70% specificity; accuracy =
0.90) to detect increased risk of mortality. Healthcare professionals may now use cut-offs of 40.5 and 36 steps in the CST to accurately detect people with ILD with functional impairment and/or
at increased risk of mortality, respectively, which may contribute
to the implementation of tailored and preventive interventions to
improve functional capacity and reduce the risk of mortality in
this population.publishe
Is Mislocalization during saccades related to the position of the saccade target within the image or to the gaze position at the end of the saccade?
A stimulus that is flashed around the time of a saccade tends to be mislocalized in the direction of the saccade target. Our question is whether the mislocalization is related to the position of the saccade target within the image or to the gaze position at the end of the saccade. We separated the two with a visual illusion that influences the perceived distance to the target of the saccade and thus saccade endpoint without affecting the perceived position of the saccade target within the image. We asked participants to make horizontal saccades from the left to the right end of the shaft of a Müller-Lyer figure. Around the time of the saccade, we flashed a bar at one of five possible positions and asked participants to indicate its location by touching the screen. As expected, participants made shorter saccades along the fins-in (<->) configuration than along the fins-out (>-<) configuration of the figure. The illusion also influenced the mislocalization pattern during saccades, with flashes presented with the fins-out configuration being perceived beyond flashes presented with the fins-in configuration. The difference between the patterns of mislocalization for bars flashed during the saccade for the two configurations corresponded quantitatively with a prediction based on compression towards the saccade endpoint considering the magnitude of the effect of the illusion on saccade amplitude. We conclude that mislocalization is related to the eye position at the end of the saccade, rather than to the position of the saccade target within the image
Examining a staging model for anorexia nervosa: empirical exploration of a four stage model of severity.
Background: An illness staging model for anorexia nervosa (AN) has received increasing attention, but assessing the merits of this concept is dependent on empirically examining a model in clinical samples. Building on preliminary findings regarding the reliability and validity of the Clinician Administered Staging Instrument for Anorexia Nervosa (CASIAN), the current study explores operationalising CASIAN severity scores into stages and assesses their relationship with other clinical features. Method: In women with DSM-IV-R AN and sub-threshold AN (all met AN criteria using DSM 5), receiver operating curve (ROC) analysis (n = 67) assessed the relationship between the sensitivity and specificity of each stage of the CASIAN. Thereafter chi-square and post-hoc adjusted residual analysis provided a preliminary assessment of the validity of the stages comparing the relationship between stage and treatment intensity and AN sub-types, and explored movement between stages after six months (Time 3) in a larger cohort (n = 171). Results: The CASIAN significantly distinguished between milder stages of illness (Stage 1 and 2) versus more severe stages of illness (Stages 3 and 4), and approached statistical significance in distinguishing each of the four stages from one other. CASIAN Stages were significantly associated with treatment modality and primary diagnosis, and CASIAN Stage at Time 1 was significantly associated with Stage at 6 month follow-up. Conclusions: Provisional support is provided for a staging model in AN. Larger studies with longer follow-up of cases are now needed to replicate and extend these findings and evaluate the overall utility of staging as well as optimal staging models
The highly rearranged mitochondrial genomes of the crabs Maja crispata and Maja squinado (Majidae) and gene order evolution in Brachyura
Abstract
We sequenced the mitochondrial genomes of the spider crabs Maja crispata and Maja squinado (Majidae, Brachyura). Both genomes contain the whole set of 37 genes characteristic of Bilaterian genomes, encoded on both \u3b1- and \u3b2-strands. Both species exhibit the same gene order, which is unique among known animal genomes. In particular, all the genes located on the \u3b2-strand form a single block. This gene order was analysed together with the other nine gene orders known for the Brachyura. Our study confirms that the most widespread gene order (BraGO) represents the plesiomorphic condition for Brachyura and was established at the onset of this clade. All other gene orders are the result of transformational pathways originating from BraGO. The different gene orders exhibit variable levels of genes rearrangements, which involve only tRNAs or all types of genes. Local homoplastic arrangements were identified, while complete gene orders remain unique and represent signatures that can have a diagnostic value. Brachyura appear to be a hot-spot of gene order diversity within the phylum Arthropoda. Our analysis, allowed to track, for the first time, the fully evolutionary pathways producing the Brachyuran gene orders. This goal was achieved by coupling sophisticated bioinformatic tools with phylogenetic analysis
Evidence for Quantum Interference in SAMs of Arylethynylene Thiolates in Tunneling Junctions with Eutectic Ga-In (EGaIn) Top-Contacts
This paper compares the current density (J) versus applied bias (V) of self-assembled monolayers (SAMs) of three different ethynylthiophenol-functionalized anthracene derivatives of approximately the same thickness with linear-conjugation (AC), cross-conjugation (AQ), and broken-conjugation (AH) using liquid eutectic Ga-In (EGaIn) supporting a native skin (~1 nm thick) of Ga2O3 as a nondamaging, conformal top-contact. This skin imparts non-Newtonian rheological properties that distinguish EGaIn from other top-contacts; however, it may also have limited the maximum values of J observed for AC. The measured values of J for AH and AQ are not significantly different (J ≈ 10-1 A/cm2 at V = 0.4 V). For AC, however, J is 1 (using log averages) or 2 (using Gaussian fits) orders of magnitude higher than for AH and AQ. These values are in good qualitative agreement with gDFTB calculations on single AC, AQ, and AH molecules chemisorbed between Au contacts that predict currents, I, that are 2 orders of magnitude higher for AC than for AH at 0 < |V| < 0.4 V. The calculations predict a higher value of I for AQ than for AH; however, the magnitude is highly dependent on the position of the Fermi energy, which cannot be calculated precisely. In this sense, the theoretical predictions and experimental conclusions agree that linearly conjugated AC is significantly more conductive than either cross-conjugated AQ or broken conjugate AH and that AQ and AH cannot necessarily be easily differentiated from each other. These observations are ascribed to quantum interference effects. The agreement between the theoretical predictions on single molecules and the measurements on SAMs suggest that molecule-molecule interactions do not play a significant role in the transport properties of AC, AQ, and AH.
One-pot synthesis and AFM imaging of a triangular aramide macrocycle
Macrocyclizations in exceptionally good yields were observed during the self-condensation of N-benzylated phenyl p-aminobenzoates in the presence of LiHMDS to yield three-membered cyclic aramides that adopt a triangular shape. An ortho-alkyloxy side chain on the N-benzyl protecting group is necessary for the macrocyclization to occur. Linear polymers are formed exclusively in the absence of this Li-chelating group. A model that explains the lack of formation of other cyclic congeners and the demand for an N-(o-alkoxybenzyl) protecting group is provided on the basis of DFT calculations. High-resolution AFM imaging of the prepared molecular triangles on a calcite(10.4) surface shows individual molecules arranged in groups of four due to strong surface templating effects and hydrogen bonding between the molecular triangles
Study of multi-carbide B4C-SiC/(Al, Si) reaction infiltrated composites by SEM with EBSD
In the definition of conceptual developments and design of new materials with singular or unique properties, characterisation takes a key role in clarifying the relationships of composition, properties and processing that define the new material. B4C has a rare combination of properties that makes it suitable for a wide range of applications in engineering: high refractoriness, thermal stability, high hardness and abrasion resistance coupled to low density. However, the low self-diffusion coefficient of B4C limits full densification by sintering. A way to overturn this constraint is by using an alloy, for example Al-Si, forming composites with B4C. Multi-carbide B4C-SiC/(Al, Si) composites were produced by the reactive melt infiltration technique at 1200 - 1350 degrees C with up to 1 hour of isothermal temperature holds. Pressed preforms made from C-containing B4C were spontaneously infiltrated with Al-Si alloys of composition varying from 25 to 50 wt% Si. The present study involves the characterisation of the microstructure and crystalline phases in the alloys and in the composites by X-ray diffraction and SEM/EDS with EBSD. Electron backscatter diffraction is used in detail to look for segregation and spatial distribution of Si and Al containing phases during solidification of the metallic infiltrate inside the channels of the ceramic matrix when the composite cools down to the eutectic temperature (577 degrees C). It complements elemental maps of the SEM/EDS. The production of a flat surface by polishing is intrinsically difficult and the problems inherent to the preparation of EBSD qualified finishing in polished samples of such type of composites are further discussed
Low Complexity Regularization of Linear Inverse Problems
Inverse problems and regularization theory is a central theme in contemporary
signal processing, where the goal is to reconstruct an unknown signal from
partial indirect, and possibly noisy, measurements of it. A now standard method
for recovering the unknown signal is to solve a convex optimization problem
that enforces some prior knowledge about its structure. This has proved
efficient in many problems routinely encountered in imaging sciences,
statistics and machine learning. This chapter delivers a review of recent
advances in the field where the regularization prior promotes solutions
conforming to some notion of simplicity/low-complexity. These priors encompass
as popular examples sparsity and group sparsity (to capture the compressibility
of natural signals and images), total variation and analysis sparsity (to
promote piecewise regularity), and low-rank (as natural extension of sparsity
to matrix-valued data). Our aim is to provide a unified treatment of all these
regularizations under a single umbrella, namely the theory of partial
smoothness. This framework is very general and accommodates all low-complexity
regularizers just mentioned, as well as many others. Partial smoothness turns
out to be the canonical way to encode low-dimensional models that can be linear
spaces or more general smooth manifolds. This review is intended to serve as a
one stop shop toward the understanding of the theoretical properties of the
so-regularized solutions. It covers a large spectrum including: (i) recovery
guarantees and stability to noise, both in terms of -stability and
model (manifold) identification; (ii) sensitivity analysis to perturbations of
the parameters involved (in particular the observations), with applications to
unbiased risk estimation ; (iii) convergence properties of the forward-backward
proximal splitting scheme, that is particularly well suited to solve the
corresponding large-scale regularized optimization problem
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