A radiomics pipeline dedicated to Breast MRI: validation on a multi-scanner phantom study

Magnetic Resonance Materials in Physics, Biology and Medicine - Quantitative analysis in MRI is challenging due to variabilities in intensity distributions across patients, acquisitions and...     

P2X7 Receptors and TMEM16 Channels Are Functionally Coupled with Implications for Macropore Formation and Current Facilitation

P2X7 receptors (P2X7) are cationic channels involved in many diseases. Following their activation by extracellular ATP, distinct signaling pathways are triggered, which lead to various physiological responses such as the secretion of pro-inflammatory cytokines or the modulation of cell death. P2X7 also exhibit unique behaviors, such as “macropore” formation, which corresponds to enhanced large molecule cell membrane permeability and current facilitation, which is caused by prolonged activation. These two phenomena have often been confounded but, thus far, no clear mechanisms have been resolved. Here, by combining different approaches including whole-cell and single-channel recordings, pharmacological and biochemical assays, CRISPR/Cas9 technology and cell imaging, we provide evidence that current facilitation and macropore formation involve functional complexes comprised of P2X7 and TMEM16, a family of Ca²⁺-activated ion channel/scramblases. We found that current facilitation results in an increase of functional complex-embedded P2X7 open probability, a result that is recapitulated by plasma membrane cholesterol depletion. We further show that macropore formation entails two distinct large molecule permeation components, one of which requires functional complexes featuring TMEM16F subtype, the other likely being direct permeation through the P2X7 pore itself. Such functional complexes can be considered to represent a regulatory hub that may orchestrate distinct P2X7 functionalities.     

Performance Evaluation of Two High‐Shear Impellers in an Unbaffled Stirred Tank

High‐shear impellers (HSIs) are mixers used in industrial stirred tanks to incorporate powders into liquids and break down particle agglomerates. A detailed numerical study of two commercial ring‐style HSIs of laboratory scale was carried out and their performance was compared with the Rushton turbine (RT). It was found that power and pumping numbers or their ratio cannot be simply connected for properly selecting an impeller in applications where highly localized viscous dissipation is desirable. The ratio of the average viscous dissipation in the impeller swept volume to the mean in the entire volume at two constant values of power input turned out to be lower for HSIs compared to that evaluated for RT. However, at higher power input, the dimensionless average viscous dissipation in the blade swept volume was found to be similar for the HSI of two rings and the RT, corroborating the high local viscous dissipation of this HSI when operated at higher speeds.     

Approximation Algorithms for Scheduling with Reservations

We study the problem of non-preemptively scheduling n independent sequential jobs on a system of m identical parallel machines in the presence of reservations, where m is constant. This setting is practically relevant because for various reasons, some machines may not be available during specified time intervals. The objective is to minimize the makespan C _max, which is the maximum completion time.     

Systolic square root covariance Kalman filtering

The square root covariance Kalman filter (SRCF) and the square root covariance Kalman predictor (SRCP) are derived from a least squares viewpoint. A new systolic array architecture is presented which is suitable for implementing both forms of the filter. The systolic SRCF is found to be comparable with other architectures in the literature in terms of size, speed and processor utilization. The SRCP is faster than any comparable architecture withO(2n) timesteps between measurements.     

Effects of refining predicted chronic dietary intakes of pesticide residues: a case study using glyphosate

A chronic consumer risk assessment based on a worst-case scenario, conducted as part of the European Union review leading to Annex I inclusion for glyphosate, was evaluated and refined. An extensive database of information on the effects of processing on the levels of glyphosate residues in food is available. This database together with refined consumption data from the UK's surveys of adults and toddlers and extensive monitoring data of glyphosate residues in mainly cereal products conducted in the UK were combined to examine the potential overestimates of dietary intakes that are predicted using the current regulatory methodology developed by the Food and Agricultural Organization/World Health Organization and applied as part of the European Union regulatory process. Analysis focussed on the chronic exposure from treated cereals, the crop group contributing significantly to the dietary intake of glyphosate residues. A steep reduction of predicted intake was seen when progressively realistic measures of residues were incorporated into the models, giving a strong indication of the conservative nature of current regulatory procedures. Calculations using even the most unrefined methodology gave rise to intakes of up to 11% of the acceptable daily intake; this was reduced to 0.6% of the acceptable daily intake when justifiable refinements based on extensive monitoring data collected in the UK were made. Consumption data for processed foods abstracted from the UK Food Standard Agency's database were used to refine further the predicted dietary intakes as a result of residue reductions or concentration from processing. The current regulatory model used in the UK generally only has the potential to use a single value for consumption of a particular food. The Pesticides Safety Directorate model consistently predicted the highest intakes with the exception of intakes by adults using the supervised trials median residue and median monitoring data. This suggests that conservatism in the regulatory model exists particularly where specific processing factors cannot be applied to individual fractions of the diet.     

Clinical validation of the Chinese Personality Assessment Inventory.

The clinical validity of the Chinese Personality Assessment Inventory (CPAI; F. M. Cheung, K. Leung, et al., 1996) was examined in 2 studies involving a group of 167 male prisoners in Hong Kong and a group of 339 psychiatric patients in China. Elevated scores on the clinical scales were obtained for the clinical samples. Logistic regression analyses confirmed that the CPAI scales were useful in differentiating between male prisoners and the Hong Kong male normative sample and between psychiatric patients and a random sample of normal adults in China. Multivariate analyses of variance results showed significant differences on the CPAI clinical scales and personality scales among subgroups of psychiatric patients with diagnoses of bipolar, schizophrenic, and neurotic disorders. The usefulness of an indigenous personality inventory is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Different ways for grafting ester derivatives of poly(ethylene glycol) onto chitosan: related characteristics and potential properties

The grafting of poly(ethylene glycol) functionalized by ester groups (MeO-PEG-ester) onto chitosan was studied and optimized using different reaction conditions. In a first procedure, the grafting was made from 6-O-triphenylmethyl-chitosan after protection of primary hydroxyl groups and in a second one, it was made directly onto chitosan. NMR spectroscopy was an important tool to study these reactions and the grafting is unequivocally showed up. Moreover, for each procedure, the solubility and surface properties of the obtained copolymers were evaluated and compared.     

Standardization of the Chinese MMPI–A in Hong Kong: A preliminary study.

The Chinese Minnesota Multiphasic Personality Inventory—Adolescents (MMPI—A) was applied in Hong Kong to a normative sample of 565 male and 664 female students ages 14–18. The Chinese adolescents' MMPI–A T scores based on the U.S. adolescent norms were elevated more than 1 SD on Scale 2. Similar elevations were found on Scale L (Lie) for the female students and on Scale A-lse (Adolescent Low Self-Esteem) for the male students. Moderate elevations were also shown on several scales, although none of the clinical scales exceeded a T score of 65, the clinical cutoff point based on U.S. norms. Whether these elevations were due to cultural differences in item interpretation or higher levels of psychopathology among the Hong Kong students cannot be concluded from the present data. However, previous findings on the Chinese MMPI favors the former explanation. These cultural differences should be taken into consideration in clinical interpretations of elevated scores on the Chinese MMPI—A. (PsycINFO Database Record (c) 2010 APA, all rights reserved)