A Study of Dental Pathology in River Otters (Lontra canadensis) in Arkansas

River otters (Lontra canadensis) consume a variety of foods, including mussels, fishes, and crayfishes. These foods have hard body parts that cause wear of the teeth as the predator ages and incurs more damaging feeding experiences. This can lead to exposure of the pulp cavity and possible abscess and resorption of bone around the alveolus. Further, strong bites against harder parts of prey sometimes results in mechanical breakage, which can lead to pulpitis and severe pathology leading to tooth loss. We investigated the frequency of different forms of dental issues in a sample of 178 skulls of river otters collected from Arkansas. Canines and carnassial teeth, most used in capture and mastication of prey, were most severely affected. Based on post-traumatic tooth wear, it is evident that otters are able to survive severe dental disease

An Overview of the association between schizotypy and dopamine

Schizotypy refers to a constellation of personality traits that are believed to mirror the subclinical expression of schizophrenia in the general population. Evidence from pharmacological studies indicates that dopamine is involved in the aetiology of schizophrenia. Based on the assumption of a continuum between schizophrenia and schizotypy, researchers have begun investigating the association between dopamine and schizotypy using a wide range of methods. In this article, we review published studies on this association from the following areas of work: (1) Experimental investigations of the interactive effects of dopaminergic challenges and schizotypy on cognition, motor control and behaviour, (2) dopaminergically supported cognitive functions, (3) studies of associations between schizotypy and polymorphisms in genes involved in dopaminergic neurotransmission, and (4) molecular imaging studies of the association between schizotypy and markers of the dopamine system. Together, data from these lines of evidence suggest that dopamine is important to the expression and experience of schizotypy and associated behavioural biases. An important observation is that the experimental designs, methods, and manipulations used in this research are highly heterogeneous. Future studies are required to replicate individual observations, to enlighten the link between dopamine and different schizotypy dimensions (positive, negative, cognitive disorganisation), and to guide the search for solid dopamine-sensitive behavioural markers. Such studies are important in order to clarify inconsistencies between studies. More work is also needed to identify differences between dopaminergic alterations in schizotypy compared to the dysfunctions observed in schizophrenia

SuFEx Postpolymerization Modification Kinetics and Reactivity in Polymer Brushes

Since its introduction in 2014, the sulfur­(VI) fluoride exchange (SuFEx) reaction has emerged as a promising new reaction in the field of polymer chemistry, in both polymerization of diverse polymer backbones and postpolymerization modification (PPM). Previously, we successfully reported the use of SuFEx chemistry as a method for surface derivatization through the PPM of sulfonyl fluoride containing polymer brushes. However, with the diversity of conditions, substrate scope, and catalyst selection afforded by this reaction, it is advantageous to expand the use of SuFEx for PPM on polymer brushes to discern the advantages and limitations of this reaction in surface conjugation. In this work, we used three different polymer brush systemsalkyl sulfonyl fluorides, aromatic sulfonyl fluorides, and aromatic fluorosulfonatesand each was reacted with three different silyl ether derivatives (aryl, alkyl, and benzyl). Each of these reactions was subjected to different catalysts, and herein, we present rates, conditions, and side products for PPM of polymer brushes using SuFEx chemistry. In addition, we explored the use of TBDMS brushes and their reaction with fluorosulfonate derivatives, where surprisingly no surface reaction occurs. With these studies, we are able to better understand the rates and limitations of this click reaction in the context of surface derivatization