Measure Of Gain Research Articles

Assessment of VOR gain function and its test-retest reliability in normal hearing individuals.

Video head impulse test (vHIT) aids to assess all three pairs of semi-circular canals (SCCs) separately and can be utilized to find out the exact site of lesion in any three SCCs by measuring vestibulo ocular reflex (VOR) gain. VOR gain value of vHIT has been used to diagnose different vestibular pathologies. Hence, it is important to establish the test-retest reliability of the VOR gain parameters before it could be administered to the patients. Therefore, the aim of the present study was to obtain VOR gain data, correlate all planes in both sides of head (right and left) and assess the test-retest reliability of VOR gain measure using vHIT in 25 normal young adult participants. Video head impulse test tests were carried out with prototype ICS impulse video goggles with a camera speed of 250frames/s, recording motion of the right eye in all three planes (lateral, right anterior left posterior, left anterior right posterior) for all the participants. vHIT testing was repeated for all the participants after 15days. Statistical analysis revealed that mean VOR gain for right horizontal canal was higher than the left horizontal canal; right anterior canal was higher than left anterior canal and left anterior was higher than right posterior canal. Horizontal canals have more gain compared to anterior and posterior canals. There was no significant difference between the VOR gain of session 1 and session 2 for each SCC.

Online recommender system for radio station hosting based on information fusion and adaptive tag-aware profiling

We present a new recommender system developed for the Russian interactive radio network FMhost. To the best of our knowledge, it is the first model and associated case study for recommending radio stations hosted by real DJs rather than automatically built streamed playlists. To address such problems as cold start, gray sheep, boosting of rankings, preference and repertoire dynamics, and absence of explicit feedback, the underlying model combines a collaborative user-based approach with personalized information from tags of listened tracks in order to match user and radio station profiles. This is made possible with adaptive tag-aware profiling that follows an online learning strategy based on user history. We compare the proposed algorithms with singular value decomposition (SVD) in terms of precision, recall, and normalized discounted cumulative gain (NDCG) measures; experiments show that in our case the fusion-based approach demonstrates the best results. In addition, we give a theoretical analysis of some useful properties of fusion-based linear combination methods in terms of graded ordered sets.

Optimal Bayesian Experimental Design for Priors of Compact Support with Application to Shock‐Tube Experiments for Combustion Kinetics

SummaryThe analysis of reactive systems in combustion science and technology relies on detailed models comprising many chemical reactions that describe the conversion of fuel and oxidizer into products and the formation of pollutants. Shock‐tube experiments are a convenient setting for measuring the rate parameters of individual reactions. The temperature, pressure, and concentration of reactants are chosen to maximize the sensitivity of the measured quantities to the rate parameter of the target reaction. In this study, we optimize the experimental setup computationally by optimal experimental design in a Bayesian framework. We approximate the posterior probability density functions (pdf) using truncated Gaussian distributions in order to account for the bounded domain of the uniform prior pdf of the parameters. The underlying Gaussian distribution is obtained in the spirit of the Laplace method, more precisely, the mode is chosen as the maximum a posteriori (MAP) estimate, and the covariance is chosen as the negative inverse of the Hessian of the misfit function at the MAP estimate. The model related entities are obtained from a polynomial surrogate. The optimality, quantified by the information gain measures, can be estimated efficiently by a rejection sampling algorithm against the underlying Gaussian probability distribution, rather than against the true posterior. This approach offers a significant error reduction when the magnitude of the invariants of the posterior covariance are comparable with the size of the bounded domain of the prior. We demonstrate the accuracy and superior computational efficiency of our method for shock‐tube experiments aiming to measure the model parameters of a key reaction, which is part of the complex kinetic network describing the hydrocarbon oxidation. In the experiments, the initial temperature and fuel concentration are optimized with respect to the expected information gain in the estimation of the parameters of the target reaction rate. We show that the expected information gain surface can change its “shape” dramatically according to the level of noise introduced into the synthetic data. The information that can be extracted from the data saturates as a logarithmic function of the number of experiments, and few experiments are needed when they are conducted at the optimal experimental design conditions. Furthermore, inversion of the legacy data indicates the validity and robustness of our designs. Copyright © 2016 John Wiley & Sons, Ltd.

Bayesian information in an experiment and the Fisher information distance

There are two forms of Fisher information; for the parameter of a model and for the information in a density model. These two forms are shown to be fundamentally connected through a measure of gain in information from a Bayesian experiment.

MRI-based cerebrovascular reactivity using transfer function analysis reveals temporal group differences between patients with sickle cell disease and healthy controls.

ObjectivesCerebrovascular reactivity (CVR) measures the ability of cerebral blood vessels to change their diameter and, hence, their capacity to regulate regional blood flow in the brain. High resolution quantitative maps of CVR can be produced using blood-oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) in combination with a carbon dioxide stimulus, and these maps have become a useful tool in the clinical evaluation of cerebrovascular disorders. However, conventional CVR analysis does not fully characterize the BOLD response to a stimulus as certain regions of the brain are slower to react to the stimulus than others, especially in disease. Transfer function analysis (TFA) is an alternative technique that can account for dynamic temporal relations between signals and has recently been adapted for CVR computation. We investigated the application of TFA in data on children with sickle cell disease (SCD) and healthy controls, and compared them to results derived from conventional CVR analysis.Materials and methodsData from 62 pediatric patients with SCD and 34 age-matched healthy controls were processed using conventional CVR analysis and TFA. BOLD data were acquired on a 3 Tesla MRI scanner while a carbon dioxide stimulus was quantified by sampling the end-tidal partial pressures of each exhaled breath. In addition, T1 weighted structural imaging was performed to identify grey and white matter regions for analysis. The TFA method generated maps representing both the relative magnitude change of the BOLD signal in response to the stimulus (Gain), as well as the BOLD signal speed of response (Phase) for each subject. These were compared to CVR maps calculated from conventional analysis. The effect of applying TFA on data from SCD patients versus controls was also examined.ResultsThe Gain measures derived from TFA were significantly higher than CVR values based on conventional analysis in both SCD patients and healthy controls, but the difference was greater in the SCD data. Moreover, while these differences were uniform across the grey and white matter regions of controls, they were greater in white matter than grey matter in the SCD group. Phase was also shown to be significantly correlated with the amount that TFA increases CVR estimates in both the grey and white matter.ConclusionsWe demonstrated that conventional CVR analysis underestimates vessel reactivity and this effect is more prominent in patients with SCD. By using TFA, the resulting Gain and Phase measures more accurately characterize the BOLD response as it accounts for the temporal dynamics responsible for the CVR underestimation. We suggest that the additional information offered through TFA can provide insight into the mechanisms underlying CVR compromise in cerebrovascular diseases.

Evaluation of a BICROS System with a Directional Microphone in the Receiver and Transmitter.

The bilateral contralateral routing of signals (BICROS) system has provided limited benefit for speech recognition in noise for patients with asymmetric sensorineural hearing loss, even when an automatic adaptive multichannel directional microphone (DM) is in the receiver (Rx) and an omnidirectional microphone (OM) is in the transmitter (Tx). A recent BICROS system was introduced that can be programmed with a DM in the Rx and an OM or a DM in the Tx. To examine if significant differences in sentence recognition in noise and subjective preferences are present between an OM and an adaptive broadband DM programmed in the Tx of a BICROS system with an automatic adaptive multichannel DM programmed in the Rx. A randomized crossover single-blind design was used to assess differences between the OM and DM programmed in the Tx. Eighteen adult experienced BICROS system users were recruited. The BICROS system was fit using real-ear insertion gain measures. The Tx was programmed with an OM and a DM and the Rx was always programmed with an automatic adaptive multichannel DM. The order of microphone condition in the Tx was counterbalanced. Participants acclimatized to the BICROS system for 4 weeks and returned and completed the Abbreviated Profile of Hearing Aid Benefit (APHAB) for the respective microphone condition. The Tx was then programmed with the other microphone condition and participants acclimatized for another four weeks. At the final visit, the APHAB was completed for the respective microphone condition. After eight weeks of acclimatization, Hearing in Noise Test sentences were presented in the R-Space™ system with the Tx in either the OM or DM condition for three listening conditions: (1) speech from 90° to the Rx and noise from 0°, 90°, and 180° to the Tx (Sp Rx/N Tx), (2) speech from 90° to the Tx and noise from 0°, 90°, and 180° to the Rx (Sp Tx/N Rx), and (3) speech from 0° and noise from eight surrounding loudspeakers separated by 45° (diffuse). A two-factor repeated measures analysis of variance revealed no significant differences between the OM and DM microphone conditions for Sp Rx/N Tx listening condition. A significant mean disadvantage of 1.9 dB (p < 0.01) was revealed for the DM compared to the OM for Sp Tx/N Rx listening condition and a mean advantage of 2.6 dB (p < 0.001) for the DM compared to the OM in a diffuse listening condition. There were no significant differences in the APHAB aided problem and resulting benefit scores between the OM and DM for the following subscales: ease of communication, background noise, reverberation, and aversiveness of sounds. No significant differences were revealed between OM and DM for Sp Rx/N Tx. The DM performed significantly poorer than OM for the Sp Tx/N Rx listening condition. Results revealed significant benefit for the DM compared to OM for the diffuse listening condition. No significant differences were revealed between the OM and DM on the APHAB.

Pursuit eye movements as an intermediate phenotype across psychotic disorders: Evidence from the B-SNIP study

Smooth pursuit eye tracking deficits are a promising intermediate phenotype for schizophrenia and possibly for psychotic disorders more broadly. The Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) consortium investigated the severity and familiality of different pursuit parameters across psychotic disorders. Probands with schizophrenia (N=265), schizoaffective disorder (N=178), psychotic bipolar disorder (N=231), their first-degree relatives (N=306, N=217, N=273, respectively) and healthy controls (N=305) performed pursuit tracking tasks designed to evaluate sensorimotor and cognitive/predictive aspects of pursuit. Probands from all diagnostic groups were impaired on all pursuit measures of interest compared to controls (p<0.001). Schizophrenia probands were more impaired than other proband groups on both early pursuit gain and predictive gain. Relatives with and without enhanced psychosis spectrum personality traits were impaired on initial eye acceleration, the most direct sensorimotor pursuit measure, but not on pursuit gain measures. This suggests that alterations in early sensorimotor function may track susceptibility to psychosis even in the absence of psychosis related personality traits. There were no differences in pursuit measures between relatives of the three proband groups. Familiality estimates of pursuit deficits indicate that early pursuit gain was more familial than predictive gain, which has been the most widely used measure in previous family studies of psychotic disorders. Thus, while disease-related factors may induce significant impairments of pursuit gain, especially in schizophrenia, the pattern of deficits in relatives and their familiality estimates suggest that alterations in sensorimotor function at pursuit onset may indicate increased susceptibility across psychotic disorders.

Growth Uncertainty And Risksharing

We propose a new methodology to evaluate the gains from global risksharing that is closely connected to the empirical growth literature. We obtain estimates of residual risk (growth uncertainty) at various horizons from regressions of country-specific deviations from world growth on a wide set of variables in the information set. Since this residual risk can be entirely hedged, we use it to obtain a measure of welfare gain that can be achieved by a representative country. We find that nations can reap very large benefits from engaging in such risksharing arrangements. Using post-war data, the gain for a 35-year horizon, corresponding to an equivalent permanent increase in consumption, is 6.6% when based on a set of 49 countries, and 1.5% when based on 21 OECD countries. Using historical data from 1870 to 1990, we find that the potential gain for a 120-year horizon ranges from 4.9% for a small set of rich countries to 16.5% for a broad set of 24 countries.

Farmers' producer organisation in reducing transactional costs: A study of Tamil Nadu Mango Growers Federation (TAMAFED)

The functional linkages of producers with different systems and within the system in the form of backward and forward linkages in production process involve the investments in the form of transactional costs. Farmers’ collective action for better production in the form of self help groups (SHGs), farmers’ interest groups (FIGs), marketing associations, producers associations, co-operatives etc. have contributed in maximizing the input-output ratio and ultimately increasing the benefit of producers. The present study was undertaken to find out the motivating factors to join association and the benefits accrued as a result of joining such producers’ federation namely TAMAFED (Tamil Nadu Mango Growers Federation) dealing with mango crop in Tamil Nadu state of India. A set of sixty member and sixty non-member farmers were selected from the six villages of the three districts of the state. The Logit analysis revealed that education, economic benefit and area under mango cultivation were the major determinants of motivation to join TAMAFED. As a measure of economic gain, transactional output cost due to sale of harvested produce was two and half times less for members compared to non-members. The comparative analysis shows that mean transactional input cost per hectare was found to be significantly lower for members than non-members. The members of TAMAFED gained social and economic benefits and the costs incurred on input and output transactions were quite low ultimately adding to the benefit. As such, it may be recommended that organization of farmers on commodity basis in the form of similar federations may be promoted for socio economic gain of the farmers.

Clinical Use of Loop Gain Measures to Determine Continuous Positive Airway Pressure Efficacy in Patients with Complex Sleep Apnea. A Pilot Study.

Measures of unstable ventilatory control (loop gain) can be obtained directly from the periodic breathing duty ratio on polysomnography in patients with Cheyne-Stokes respiration/central sleep apnea and can predict the efficacy of continuous positive airway pressure (CPAP) therapy. In this pilot study, we aimed to determine if this measure could also be applied to patients with complex sleep apnea (predominant obstructive sleep apnea, with worsening or emergent central apneas on CPAP). We hypothesized that loop gain was higher in patients whose central events persisted 1 month later despite CPAP treatment versus those whose events resolved over time. We calculated the duty ratio of the periodic central apneas remaining on the CPAP titration (or second half of the split night) while patients were on optimal CPAP with the airway open (obstructive apnea index < 1/h). Loop gain was calculated by the formula: LG = 2π/[(2πDR - sin(2πDR)]. Patients were followed on CPAP for 1 month. Post-treatment apnea-hypopnea index and compliance data were recorded from smart cards. Thirty-two patients with complex sleep apnea were identified, and 17 patients had full data sets. Eight patients continued to have a total of more than five events per hour (11.8 ± 0.5/h) (nonresponders). The remaining nine patients had an apnea-hypopnea index less than 5/h (2.2 ± 0.4/h) (responders). Loop gain was higher in the nonresponders versus responders (2.0 ± 0.1 vs. 1.7 ± 0.2, P = 0.026). Loop gain and the residual apnea-hypopnea index 1 month after CPAP were associated (r = 0.48, P = 0.02). CPAP compliance was similar between groups. In this pilot study, loop gain was higher for patients with complex sleep apnea in whom central apneas persisted after 1 month of CPAP therapy (nonresponders). Loop gain measurement may enable an a priori determination of those who need alternative modes of positive airway pressure.

Fast Edge Detection Using Structured Forests.

Edge detection is a critical component of many vision systems, including object detectors and image segmentation algorithms. Patches of edges exhibit well-known forms of local structure, such as straight lines or T-junctions. In this paper we take advantage of the structure present in local image patches to learn both an accurate and computationally efficient edge detector. We formulate the problem of predicting local edge masks in a structured learning framework applied to random decision forests. Our novel approach to learning decision trees robustly maps the structured labels to a discrete space on which standard information gain measures may be evaluated. The result is an approach that obtains realtime performance that is orders of magnitude faster than many competing state-of-the-art approaches, while also achieving state-of-the-art edge detection results on the BSDS500 Segmentation dataset and NYU Depth dataset. Finally, we show the potential of our approach as a general purpose edge detector by showing our learned edge models generalize well across datasets.

The extension of total gain (TG) statistic in survival models: properties and applications.

BackgroundThe results of multivariable regression models are usually summarized in the form of parameter estimates for the covariates, goodness-of-fit statistics, and the relevant p-values. These statistics do not inform us about whether covariate information will lead to any substantial improvement in prediction. Predictive ability measures can be used for this purpose since they provide important information about the practical significance of prognostic factors. R2-type indices are the most familiar forms of such measures in survival models, but they all have limitations and none is widely used.MethodsIn this paper, we extend the total gain (TG) measure, proposed for a logistic regression model, to survival models and explore its properties using simulations and real data. TG is based on the binary regression quantile plot, otherwise known as the predictiveness curve. Standardised TG ranges from 0 (no explanatory power) to 1 (‘perfect’ explanatory power).ResultsThe results of our simulations show that unlike many of the other R2-type predictive ability measures, TG is independent of random censoring. It increases as the effect of a covariate increases and can be applied to different types of survival models, including models with time-dependent covariate effects. We also apply TG to quantify the predictive ability of multivariable prognostic models developed in several disease areas.ConclusionsOverall, TG performs well in our simulation studies and can be recommended as a measure to quantify the predictive ability in survival models.Electronic supplementary materialThe online version of this article (doi:10.1186/s12874-015-0042-x) contains supplementary material, which is available to authorized users.

Fat and Thin Sex: Fetishised Normal and Normalised Fetish

Fat and Thin Sex: Fetishised Normal and Normalised Fetish

Characterizing gene-gene interactions in a statistical epistasis network of twelve candidate genes for obesity.

BackgroundRecent findings have reemphasized the importance of epistasis, or gene-gene interactions, as a contributing factor to the unexplained heritability of obesity. Network-based methods such as statistical epistasis networks (SEN), present an intuitive framework to address the computational challenge of studying pairwise interactions between thousands of genetic variants. In this study, we aimed to analyze pairwise interactions that are associated with Body Mass Index (BMI) between SNPs from twelve genes robustly associated with obesity (BDNF, ETV5, FAIM2, FTO, GNPDA2, KCTD15, MC4R, MTCH2, NEGR1, SEC16B, SH2B1, and TMEM18).MethodsWe used information gain measures to identify all SNP-SNP interactions among and between these genes that were related to obesity (BMI > 30 kg/m2) within the Framingham Heart Study Cohort; interactions exceeding a certain threshold were used to build an SEN. We also quantified whether interactions tend to occur more between SNPs from the same gene (dyadicity) or between SNPs from different genes (heterophilicity).ResultsWe identified a highly connected SEN of 709 SNPs and 1241 SNP-SNP interactions. Combining the SEN framework with dyadicity and heterophilicity analyses, we found 1 dyadic gene (TMEM18, P-value = 0.047) and 3 heterophilic genes (KCTD15, P-value = 0.045; SH2B1, P-value = 0.003; and TMEM18, P-value = 0.001). We also identified a lncRNA SNP (rs4358154) as a key node within the SEN using multiple network measures.ConclusionThis study presents an analytical framework to characterize the global landscape of genetic interactions from genome-wide arrays and also to discover nodes of potential biological significance within the identified network.Electronic supplementary materialThe online version of this article (doi:10.1186/s13040-015-0077-x) contains supplementary material, which is available to authorized users.

Effects of omics data combinations on in silico tumor-normal tissue classification

A disease can be characterized by various attributes such as genomic, epigenetic, and transcriptomic features beyond physiological symptoms. The accumulation of vast datasets allows us to investigate the relative effectiveness of each omics data and their combinations for in silico analysis of diseases. Here, we employed a classification method with the well-established measure of information gain for the computational analysis of the effect of the aggregation of omics data, especially for the task of in silico classification of tumor-normal samples for bladder urothelial carcinoma and kidney renal papillary cell carcinoma. We observed that the combination of multi-omics data such as copy number variation, DNA methylation, RNA-Seq, and somatic mutations have beneficial effects. The quantitative analysis using information gain and various measures for classification-performance showed that the combination of multiple omics data improved the performance in general. The qualitative analysis referring previous researches also confirmed the relevance of genes with higher information gain to target diseases. Our results report that the combination of multiple omics data is beneficial and the information gain which focuses on the distribution of attributes across target domains could be useful as an indicator of the effect of each omics data on tumor-normal sample classification.

Night-eating symptoms and 2-year weight change in parents enrolled in the QUALITY cohort.

The timing of food intake may be implicated in weight gain. This study tested the hypothesis that symptoms commonly associated with night-eating syndrome are related to measures of weight gain in adults. Parents participating in QUALITY (Québec Adipose and Lifestyle InvesTigation in Youth) completed the night eating questionnaire (NEQ) at baseline (2005-2008) and at follow-up (2008-2010). Height and weight were measured and self-report questionnaire data were available for 388 parents (59% female, mean (s.d.) age: 41.8±5.7, mean (s.d.) body mass index (BMI): 29.6±5.7). Linear regression models were used to test the associations between baseline night-eating symptoms (NEQ scores, night-eating behaviours) and percent change in each of BMI and waist circumference (WC). A high NEQ score predicted a small increase in percent change in BMI in nonobese parents but a decrease among those who were severely obese. Nocturnal ingestions of food predicted an increase in percent change in BMI; however, the effect size was small. Morning anorexia predicted an increase in percent change in WC. Certain night-eating symptoms may predict measures of weight gain in adults but the effects seem small and the findings need to be confirmed in more symptomatic samples.

VOR gain by head impulse video-oculography differentiates acute vestibular neuritis from stroke.

Vestibular neuritis is often mimicked by stroke (pseudoneuritis). Vestibular eye movements help discriminate the two conditions. We report vestibulo-ocular reflex (VOR) gain measures in neuritis and stroke presenting acute vestibular syndrome (AVS). Prospective cross-sectional study of AVS (acute continuous vertigo/dizziness lasting >24 h) at two academic centers. We measured horizontal head impulse test (HIT) VOR gains in 26 AVS patients using a video HIT device (ICS Impulse). All patients were assessed within 1 week of symptom onset. Diagnoses were confirmed by clinical examinations, brain magnetic resonance imaging with diffusion-weighted images, and follow-up. Brainstem and cerebellar strokes were classified by vascular territory-posterior inferior cerebellar artery (PICA) or anterior inferior cerebellar artery (AICA). Diagnoses were vestibular neuritis (n = 16) and posterior fossa stroke (PICA, n = 7; AICA, n = 3). Mean HIT VOR gains (ipsilesional [standard error of the mean], contralesional [standard error of the mean]) were as follows: vestibular neuritis (0.52 [0.04], 0.87 [0.04]); PICA stroke (0.94 [0.04], 0.93 [0.04]); AICA stroke (0.84 [0.10], 0.74 [0.10]). VOR gains were asymmetric in neuritis (unilateral vestibulopathy) and symmetric in PICA stroke (bilaterally normal VOR), whereas gains in AICA stroke were heterogeneous (asymmetric, bilaterally low, or normal). In vestibular neuritis, borderline gains ranged from 0.62 to 0.73. Twenty patients (12 neuritis, six PICA strokes, two AICA strokes) had at least five interpretable HIT trials (for both ears), allowing an appropriate classification based on mean VOR gains per ear. Classifying AVS patients with bilateral VOR mean gains of 0.70 or more as suspected strokes yielded a total diagnostic accuracy of 90%, with stroke sensitivity of 88% and specificity of 92%. Video HIT VOR gains differ between peripheral and central causes of AVS. PICA strokes were readily separated from neuritis using gain measures, but AICA strokes were at risk of being misclassified based on VOR gain alone.

The Effectiveness of Online Versus In-person Library Instruction on Finding Empirical Communication Research

With online education becoming more popular, the following study compares the effectiveness of online versus in-person library instruction with regards to teaching communication students how to seek empirical research to use in their class projects. Measures of knowledge gain and attitudes revealed significant differences across time showing success of the instruction, but non-significant differences between the modes of instruction. However, a behavioral measure found that almost 10% more students in the online condition were able to successfully find empirical articles to use in their projects than those in the in-person instructional condition. With empirical research living less at brick-and-mortar libraries and primarily in online repositories, teaching students how to find empirical research may be most successful when it is taught via online platforms.

Is driving assisted behaviour infectious?: Using spectral analysis to understand car following behaviour of naïve drivers

Is driving assisted behaviour infectious?: Using spectral analysis to understand car following behaviour of naïve drivers

A refined high carbohydrate diet is associated with changes in the serotonin pathway and visceral obesity.

Consumption of palatable foods high in refined carbohydrate has been implicated as a contributing factor to the epidemic levels of obesity. Such foods may disrupt appetite regulation in the hypothalamus through alterations in hunger and satiety signalling. This investigation examined whether a palatable high refined carbohydrate (HRC) diet with the potential to induce obesity was linked to modulation of serotonin and dopamine signalling within the hypothalamus of rats. Male Wistar rats were allowed ad libitum access to either a palatable refined carbohydrate enriched (HRC) diet or standard chow (SC). Visceral fat percentage was used as a measure of the animals' weight gain during the trial. Real-time PCR was applied to determine any variation in levels of expression of the serotonin (Slc6A4 or Sert) and dopamine transporter (Slc6A3 or Dat) genes. After 29 weeks, the HRC group showed a significant increase in visceral fat percentage accompanied by increased expression of Sert. Higher levels of circulating triglycerides were also seen. This investigation determined that a refined high carbohydrate diet is associated with visceral obesity, increased circulating lipids in the blood and distorted serotonergic signalling, which possibly alters satiety and hunger signals.