Neurocognitive change over the course of a multiday external lumbar drain trial in patients with suspected normal pressure hydrocephalus.

To characterize neurocognitive response to cerebrospinal fluid (CSF) diversion during a multiday external lumbar drainage (ELD) trial in patients with suspected normal pressure hydrocephalus (NPH). Inpatients ( = 70) undergoing an ELD trial as part of NPH evaluation participated. Cognition and balance were assessed using standardized measures before and after a three-day ELD trial.

Functional silicone oils and elastomers: new routes lead to new properties.

Silicones are mostly utilized for their stability to a range of vigorous environmental conditions, which arises, in part, from the lack of functionality in finished products. The commonly used functional groups in silicones, , SiH, SiCHCH, are mostly consumed during final product synthesis. Organic functional groups may also be found in silicone products, including organic alcohols, amines, polyethers, , that deliver functionality not achieved by traditional organic polymers (, aminosilicones, softening of fabrics; silicone polyethers, superwetting agricultural adjuvants).

Exploring Lipoic Acid-Mediated Dynamic Bottlebrush Elastomers as a New Platform for the Design of High-Performance Thermally Conductive Materials.

The development of high-performance thermally conductive interface materials is the key to unlocking the serious bottleneck of modern microelectronic technology through enhanced heat dispersion. Existing methods that utilize silicone composites rely either on loading large doses of randomly distributed thermal conductive fillers or on filling prealigned thermal conductive scaffolds with liquid silicone precursors. Both approaches suffer from several limitations in terms of physical traits and processability.

Perceived cognitive impairment is related to internalizing psychopathology but unrelated to objective cognitive performance among nongeriatric adults presenting for outpatient neuropsychological evaluation.

This study investigated the relationship between perceived cognitive impairment, objective cognitive performance, and intrapersonal variables thought to influence ratings of perceived cognitive impairment. Study sample comprised 194 nongeriatric adults who were seen in a general outpatient neuropsychology clinic for a variety of referral questions. The cognition subscale score from the WHO Disability Assessment Schedule served as the measure of perceived cognitive impairment.

Antioxidant Silicone Elastomers without Covalent Cross-Links.

Improved sustainability is associated with elastomers that readily breakdown in the environment at end of life and, as importantly, that can be reprocessed/reused long before end of life arises. We report the preparation of silicone elastomers that possess both thermoplasticity-reprocessability-and antioxidant activity. A combination of ionic and H-bonding links natural phenolic antioxidants, including catechol, pyrogallol, tannic acid, and others, to telechelic aminoalkylsilicones.

Preparation of ultra-thin elastomeric films.

When polydimethylsiloxane elastomers are produced, in the absence of great care, chains remain that are unbound to the cross-linked matrix. Due to the unbound chains swelling the crosslinked matrix, these materials are gels. We have developed a simple process to prepare well-controlled elastomeric thin films which do not rely on unknown commercial formulations.

Starch-Directed Synthesis of Worm-Shaped Silica Microtubes.

Many strategies have been adopted to prepare silica materials with highly controlled structures, typically using sol-gel chemistry. Frequently, the alkoxysilanes used in sol-gel chemistry are based on monoalcohols, e.g.

Ascorbic Acid-Modified Silicones: Crosslinking and Antioxidant Delivery.

Vitamin C is widely used as an antioxidant in biological systems. The very high density of functional groups makes it challenging to selectively tether this molecule to other moieties. We report that, following protection of the enediol as benzyl ethers, the introduction of an acrylate ester at C1 is straightforward.

Profile of Embedded Validity Indicators in Criminal Defendants with Verified Valid Neuropsychological Test Performance.

Objective: Few studies have examined the use of embedded validity indicators (EVIs) in criminal-forensic practice settings, where judgements regarding performance validity can carry severe consequences for the individual and society. This study sought to examine how various EVIs perform in criminal defendant populations, and determine relationships between EVI scores and intrapersonal variables thought to influence performance validity.

Method: Performance on 16 empirically established EVI cutoffs were examined in a sample of 164 criminal defendants with valid performance who were referred for forensic neuropsychological evaluation.

A Measurement-Based Protocol Improves Interrater Agreement and Accuracy of Right Ventricular Systolic Pressure Assessment by Echocardiography in Children: A Call for Quality Improvement.

Background: Echocardiographic measurements carry the promise of improving interrater (IR) agreement over subjective assessment. The aim of this study was to assess the effect of implementing a measurement-based protocol on IR agreement and accuracy in reporting of right ventricular (RV) systolic pressure in children. The effect of this reporting protocol on IR agreement in reporting RV dilation, hypertrophy, and systolic function was also evaluated.

Chelating Silicone Dendrons: Trying to Impact Organisms by Disrupting Ions at Interfaces.

The viability of pathogens at interfaces can be disrupted by the presence of (cationic) charge and chelating groups. We report on the synthesis of silicone dendrimers and linear polymers based on a motif of hexadentate ligands with the ability to capture and deliver metal ions. Mono-, di- or trialkoxysilanes are converted in G1 to analogous vinylsilicones and then, iteratively using the Piers-Rubinsztajn reaction and hydrosilylation, each vinyl group is transformed into a trivinyl cluster at G2.

High Refractive Index, Enantiopure Silicones Based on BINOL.

The high refractive index aromatic compound, binaphthol (BINOL), is readily incorporated into silicone polymer chains using the Piers-Rubinsztajn (PR) reaction; alternating and random linear copolymers, and elastomers are available. The highest refractive index (RI) materials are BINOL rich. It is not possible to directly make high refractive index linear polymers with very short HSi-capped, telechelic silicone chains, as they do not react cleanly.

Naturally Derived Silicone Surfactants Based on Saccharides and Cysteamine.

Silicone surfactants are widely used in many industries and mostly rely on poly(ethylene glycol) (PEG) as the hydrophile. This can be disadvantageous because commercial PEG examples vary significantly in polydispersity-constraining control over surface activity of the surfactant-and there are environmental concerns associated with PEG. Herein, we report a three-step synthetic method for the preparation of saccharide-silicone surfactants using the natural linker, cysteamine, and saccharide lactones.

Phonological processing in psychopathic offenders.

Recent research has demonstrated that psychopathic offenders exhibit dynamic cognitive and behavioral deficits on a variety of lab tasks that differentially activate left hemisphere resources. The Left Hemisphere Activation (LHA) hypothesis is a cognitive perspective that aims to address these deficits by conceptualizing psychopathy as a disorder in which behavior and cognitive processing change dynamically as a function of the differential taxation of left hemisphere resources. This study aimed to investigate whether psychopathic traits are associated with electrophysiological anomalies under conditions that place differential demands on left hemisphere language processing systems.

Spatially Controlled Highly Branched Vinylsilicones.

Branched silicones possess interesting properties as oils, including their viscoelastic behavior, or as precursors to controlled networks. However, highly branched silicone polymers are difficult to form reliably using a "grafting to" strategy because functional groups may be bunched together preventing complete conversion for steric reasons. We report the synthesis of vinyl-functional highly branched silicone polymers based, at their core, on the ability to spatially locate functional vinyl groups along a silicone backbone at the desired frequency.

When Attempting Chain Extension, Even Without Solvent, It Is Not Possible to Avoid Chojnowski Metathesis Giving D.

A simple, mild and efficient method to prepare HSi- or HOSi-telechelic, high-molecular-weight polydimethylsiloxane polymers (to 41,600 g·mol) using the one-shot hydrolysis of MM is reported; titration of the water allowed for higher molecular weights (to 153,900 g·mol). The "living" character of the chain extension processes was demonstrated by adding a small portion of MM and B(CF) (BCF) to a first formed polymer, which led to a ~2-fold, second growth in molecular weight. The heterogeneous reaction reached completion in less than 30 min, much less in some cases, regardless of whether it was performed neat or 50 wt% in dry toluene; homogeneous reactions in toluene were much slower.

Synergistic effect of carotenoid and silicone-based additives for photooxidatively stable organic solar cells with enhanced elasticity.

Photochemical and mechanical stability are critical in the production and application of organic solar cells. While these factors can individually be improved using different additives, there is no example of studies on the combined effects of such additive-assisted stabilization. In this study, the properties of PTB7:[70]PCBM organic solar cells are studied upon implementation of two additives: the carotenoid astaxanthin (AX) for photochemical stability and the silicone polydimethylsiloxane (PDMS) for improved mechanical properties.

Reliable Condensation Curing Silicone Elastomers with Tailorable Properties.

The long-term stability of condensation curing silicone elastomers can be affected by many factors such as curing environment, cross-linker type and concentration, and catalyst concentration. Mechanically unstable silicone elastomers may lead to undesirable application failure or reduced lifetime. This study investigates the stability of different condensation curing silicone elastomer compositions.

PEG-containing siloxane materials by metal-free click-chemistry for ocular drug delivery applications.

Metal-free click-chemistry can be used to create silicone hydrogels for ocular drug delivery applications, imparting the benefits of silicones without catalyst contamination. Previous work has demonstrated the capacity for these materials to significantly reduce protein adsorption. Building upon this success, the current work examines and optimizes different materials in terms of their protein adsorption and drug release capabilities.

Dynamically tuning transient silicone polymer networks with hydrogen bonding.

Supramolecular polymers are composed of non-covalently connected chains and characterized by high chain dynamics. The viscoelastic behavior of supramolecular telechelic sugar-siloxanes - ranging from solids to viscous fluids able to form transient polymer networks - is readily tuned by the fraction of internal HO groups that can intermolecularly form hydrogen bonds.

Psychopathy is associated with fear-specific reductions in neural activity during affective perspective-taking.

Psychopathic individuals are notorious for their callous disregard for others' emotions. Prior research has linked psychopathy to deficits in affective mechanisms underlying empathy (e.g.

Reversible Redox Crosslinking of Thiopropylsilicones.

Most silicone elastomers are thermosets. As a response to the new paradigm of polymer recyclability, the development of silicone elastomers that can be reversibly and repeatedly cured and uncrosslinked using redox conditions is reported. Thiopropyl-modified silicones are oxidized to elastomers with disulfide crosslinks using the organosoluble oxidant PhI(OAc) .

Differentiating Perpetrators of Intimate Partner Violence From Other Violent Offenders Using a Statistical Learning Model: The Role of Cognition and Life History Variables.

Intimate partner violence (IPV) is a widespread crime that victimizes over 4-million women per year in the United States and results in significant monetary cost and unmeasured physical and psychological consequences for victims. Specialized IPV offender treatment programs demonstrate limited effectiveness, which may be due to an insufficient understanding of the factors that differentiate between IPV perpetrators and non-IPV violent offenders. In this study, we utilized classification and regression tree (CART) analysis to identify combinations of factors that best discriminate IPV perpetrators from non-IPV violent offenders.

Compatibilization of porphyrins for use as high permittivity fillers in low voltage actuating silicone dielectric elastomers.

Polysiloxanes represent, because of their unusual properties, a material with great potential for use in dielectric elastomers (DEs), a promising class of electroactive polymers. Currently, their application as actuators is limited by the need for high driving voltages, as a result of the low relative permittivity possessed by polysiloxanes (∼2-3). Reducing these voltages can be achieved to some degree by using high permittivity additives to improve the permittivity of the polysiloxane.