Psychopathological and Neurobiological Overlap Between Anorexia Nervosa and Self-Injurious Behavior: A Narrative Review and Conceptual Hypotheses

Empirical evidence and clinical observations suggest a strong -yet under acknowledged-link between anorexia nervosa (AN) and non-suicidal self-injurious behavior (NSSI). By reviewing the literature on the psychopathology and neurobiology of AN and NSSI, we shed light on their relationship. Both AN and NSSI are characterized by disturbances in affect regulation, dysregulation of the reward circuitry and the opioid system. By formulating a reward-centered hypothesis, we explain the overlap between AN and NSSI. We propose three approaches understanding the relationship between AN and NSSI, which integrate psychopathology and neurobiology from the perspective of self-destructiveness: (1) a nosographical approach, (2) a research domain (RDoC) approach and (3) a network analysis approach. These approaches will enhance our knowledge of the underlying neurobiological substrates and may provide groundwork for the development of new treatment options for disorders of self-destructiveness, like AN and NSSI. In conclusion, we hypothesize that self-destructiveness is a new, DSM-5-transcending concept or psychopathological entity that is reward-driven, and that both AN and NSSI could be conceptualized as disorders of self-destructiveness.

Cross-cohort generalizability of deep and conventional machine learning for MRI-based diagnosis and prediction of Alzheimer's disease

This work validates the generalizability of MRI-based classification of Alzheimer’s disease (AD) patients and controls (CN) to an external data set and to the task of prediction of conversion to AD in individuals with mild cognitive impairment (MCI).

We used a conventional support vector machine (SVM) and a deep convolutional neural network (CNN) approach based on structural MRI scans that underwent either minimal pre-processing or more extensive pre-processing into modulated gray matter (GM) maps. Classifiers were optimized and evaluated using cross-validation in the Alzheimer’s Disease Neuroimaging Initiative (ADNI; 334 AD, 520 CN). Trained classifiers were subsequently applied to predict conversion to AD in ADNI MCI patients (231 converters, 628 non-converters) and in the independent Health-RI Parelsnoer Neurodegenerative Diseases Biobank data set. From this multi-center study representing a tertiary memory clinic population, we included 199 AD patients, 139 participants with subjective cognitive decline, 48 MCI patients converting to dementia, and 91 MCI patients who did not convert to dementia.

AD-CN classification based on modulated GM maps resulted in a similar area-under-the-curve (AUC) for SVM (0.940; 95%CI: 0.924–0.955) and CNN (0.933; 95%CI: 0.918–0.948). Application to conversion prediction in MCI yielded significantly higher performance for SVM (AUC = 0.756; 95%CI: 0.720-0.788) than for CNN (AUC = 0.742; 95%CI: 0.709-0.776) (p<0.01 for McNemar’s test). In external validation, performance was slightly decreased. For AD-CN, it again gave similar AUCs for SVM (0.896; 95%CI: 0.855–0.932) and CNN (0.876; 95%CI: 0.836–0.913). For prediction in MCI, performances decreased for both SVM (AUC = 0.665; 95%CI: 0.576-0.760) and CNN (AUC = 0.702; 95%CI: 0.624-0.786). Both with SVM and CNN, classification based on modulated GM maps significantly outperformed classification based on minimally processed images (p=0.01).

Deep and conventional classifiers performed equally well for AD classification and their performance decreased only slightly when applied to the external cohort. We expect that this work on external validation contributes towards translation of machine learning to clinical practice.

A Distributed Medical Data Base

This paper describes the design and implementation of a distributed medical data base. Basic to this concept is a network of minicomputers, each of which possesses files which can be accessed throughout, the network by a protocol involving the NAMEs of the data fields. Physical and logical descriptor maps for the files provide mechanisms for protecting privileged information as well as tailoring the appearance of the data to suit the needs of jDarticular users.

Frequency Band-Specific Electrical Brain Stimulation Modulates Cognitive Control Processes

A large body of findings has tied midfrontal theta-band (4-8 Hz) oscillatory activity to adaptive control mechanisms during response conflict. Thus far, this evidence has been correlational. To evaluate whether theta oscillations are causally involved in conflict processing, we applied transcranial alternating current stimulation (tACS) in the theta band to a midfrontal scalp region, while human subjects performed a spatial response conflict task. Conflict was introduced by incongruency between the location of the target stimulus and the required response hand. As a control condition, we used alpha-band (8-12 Hz) tACS over the same location. The exact stimulation frequencies were determined empirically for each subject based on a pre-stimulation EEG session. Behavioral results showed general conflict effects of slower response times (RT) and lower accuracy for high conflict trials compared to low conflict trials. Importantly, this conflict effect was reduced specifically during theta tACS, which was driven by slower response times on low conflict trials. These results show how theta tACS can modulate adaptive cognitive control processes, which is in accordance with the view of midfrontal theta oscillations as an active mechanism for cognitive control.

Hydrogels from phospholipid vesicles

It is shown that phospholipid dispersions with a few percent of diacylphosphocholine PC in water can be swollen to single-phase lyotropic liquid crystalline Lα-phases by the addition of co-solvents like glycerol, 1,3-butyleneglycol BG or 1,2-propyleneglycol PG. The birefringent Lα-phases contain small unilamellar and multilamellar vesicles if the temperature of the samples is above the Krafft-Temperature Tm of the phospholipid. When such transparent birefringent viscous samples are cooled down below Tm the samples are transformed into birefringent gels. Cryo-TEM and FF-TEM measurements show that the bilayers of the vesicles are transformed from the liquid to the crystalline state during the transformation while the vesicle structure remains. The bilayers of the crystalline vesicles form adhesive contacts in the gel. Pulsed-field gradient NMR measurements show that two different kinds of water or co-solvent can be distinguished in the gels. One type of solvent molecules can diffuse like normal solvent in a continuous bulk phase. A second type of water diffuses much more slowly. This type of solvent is obviously trapped in the vesicles. The permeability of the crystalline vesicles for water and solvent molecules is much lower in the crystalline state than in the fluid state. Maximum swelling of the diacylphosphocholin dispersions occurs when the refractive index of the solvent is matched to the refractive index of the bilayers. The attraction between the bilayers is at a minimum in this state and the liquid crystalline Lα-phase's undulation forces between the bilayers push the bilayers apart. On transformation to the gel state the crystalline bilayers assume a high elastic bending rigidity. Undulations of the bilayers are now suppressed, and the bilayers can form adhesive contacts. Oscillating rheological measurements show that the gels with only 1% of phospholipids can have a storage modulus of 1000Pa. The gels are very brittle. They break when they are deformed by a few percent.

Foliar Interception and Retention Values after Pesticide Application. A Proposal for Standardized Values for Environmental Risk Assessment (Technical Report)

In performing risk assessments for plant protection products by applicants or regulators in relation to the registration of the products, an important aspect to take into account is the foliar interception and retention of the active substance of the product on the plant. An overview is given of the approaches to this item in several parts of the world. The relevant circumstances and influencing variables, such as growth phase, planting density, and some physicochemical characteristics (e.g., vapor pressure and Henry's coefficient) are dealt with. Finally, a proposal is presented for how to take into account the phenomenon of foliar interception and retention in the initial phase, first tier, of the risk assessment process.