N-Terminal Modification of Gly-His-Tagged Proteins with Azidogluconolactone

Site-specific protein modifications are vital for biopharmaceutical drug development. Gluconoylation is a non-enzymatic, post-translational modification of N-terminal HisTags. We report high-yield, site-selective in vitro α-aminoacylation of peptides, glycoproteins, antibodies, and virus-like particles (VLPs) with azidogluconolactone at pH 7.5 in 1 h. Conjugates slowly hydrolyse, but diol-masking with borate esters inhibits reversibility. In an example, we multimerise azidogluconoylated SARS-CoV-2 receptor-binding domain (RBD) onto VLPs via click-chemistry, to give a COVID-19 vaccine. Compared to yeast antigen, HEK-derived RBD was immunologically superior, likely due to observed differences in glycosylation. We show the benefits of ordered over randomly oriented multimeric antigen display, by demonstrating single-shot seroconversion and best virus-neutralizing antibodies. Azidogluconoylation is simple, fast and robust chemistry, and should accelerate research and development.     

On the Merits of Clinical Judgment: Comment.

Comments on the article by D. Westen and J. Weinberger (see record 2004-19091-002), which criticized academic clinical psychologists for being cynical about clinical judgment and clinical practice. In our view, it seems unlikely that more than a few academic clinical psychologists believe that they have little to learn from clinical practice or experience. In this comment, we examine the arguments about clinical judgment made by Westen and Weinberger (2004). Westen and Weinberger (2004) conflate the effect of training with the effect of experience. Westen and Weinberger (2004) do not mention that the value of training in psychology has been well-supported by research. While Westen and Weinberger (2004) make positive comments about the types of feedback that clinicians receive, for a number of reasons, including the Barnum effect, psychologists can be misled by feedback. Westen and Weinberger (2004) also argue that "psychotherapists tend to have much more direct and immediate feedback than most other medical practitioners, who may prescribe a medication or perform a procedure and not see the patient again for a year" (p. 603). But when psychologists make a diagnosis or describe a personality trait, they frequently do not receive "direct and immediate feedback" on whether they are right or wrong. In contrast, physicians often receive highly valid feedback. Finally, in discussing the value of ratings made by clinicians, Westen and Weinberger (2004) observe that "empirically, we have found surprisingly little evidence of theory-driven observational bias in using clinician-report methods" (p. 601). The issue is important because Westen and Weinberger argue in favor of using clinician ratings to construct diagnostic criteria. If clinicians' ratings are biased, then the criteria will be biased. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Numerical and experimental investigation of solid particle motion in a fluid cell under microgravity

This research aims at understanding the mechanisms and parameters that affect particle motion induced by g-jitter. Simultaneous experimental (parabolic flights) and numerical work was conducted to study the motion of a spherical particle in a microgravity environment subjected to vibrations in either horizontal or vertical direction. The data from both vertically and horizontally vibrated experiments clearly show that the investigated particle properties, size and density, affect the amplitude of the particle motion. In all experiments the amplitude of the particle motion increased with the density and diameter of the particle in the cell frame of reference. It was also observed that the particles moved at the frequency equal to that of applied vibration. These results are consistent with the preliminary numerical simulation predictions. Numerical simulations also showed that increasing the viscosity of the surrounding fluid would reduce the amplitude of the particle motion.     

Evaluating the usability of a mobile guide: the influence of location, participants and resources

When designing a usability evaluation, choices must be made regarding methods and techniques for data collection and analysis. Mobile guides raise new concerns and challenges to established usability evaluation approaches. Not only are they typically closely related to objects and activities in the user's immediate surroundings, they are often used while the user is ambulating. This paper presents results from an extensive, multi-method evaluation of a mobile guide designed to support the use of public transport in Melbourne, Australia. In evaluating the guide, we applied four different techniques; field-evaluation, laboratory evaluation, heuristic walkthrough and rapid reflection. This paper describes these four approaches and their respective outcomes, and discusses their relative strengths and weaknesses for evaluating the usability of mobile guides.     

Vicarious experience in retail e-commerce: An inductive taxonomy of product evaluation support features

In general, direct experience (touch, taste, use, and so on) of physical products is impossible in an online environment. Knowledge of the experience attributes of these goods must therefore be obtained via an intermediary (vicariously). Unfortunately, little has been published about how to design online retail systems that help customers evaluate physical products. This paper addresses that gap by (1) surveying a wide range of sites, and (2) evaluating the features found using a grounded, rigorous evaluation method to induce a taxonomy of vicarious experience. The taxonomy is then used as the basis for some theory-based conjectures about the types of designs most suitable for different types of product. In particular, we propose that the type of information form and community used should differ for value-expressive and utilitarian goods, and for high and low-involvement goods.     

A Systematic Approach to Predict Performance of Human–Automation Systems

This paper discusses an approach for predicting system performance resulting from humans and robots performing repetitive tasks in a collaborative manner. The methodology uses a systematic approach that incorporates the various effects of workload on human performance, and estimates resulting performance attributes derived between teleoperated and autonomous control of robotic systems. Performance is determined by incorporating capabilities of the human and robotic agent based on accomplishment of functional operations and effect of cognitive stress due to continuous operation by the human agent. This paper provides an overview of the prediction system and discusses its implementation on a simulated rendezvous/docking task.     

Determining the incremental worth of members of an aggregate set through difference-based induction

Calculating the incremental worth or weight of individual components of an aggregate set when only the whole set's total worth or weight is known is a problem common to several domains. Here we describe an algorithm that induces such incremental worth from a database of similar (not identical) aggregate sets. The algorithm focuses on finding aggregate sets in the database exhibiting minimal differences in corresponding components (attributes and values). This procedure isolates dissimilarities between nearly similar aggregate sets so any difference in worth between sets is attributed to them. The algorithm builds a classification tree similar to those of ID3 and C4.5 distributes all aggregate sets in the database according to their attributes and values; and groups together those with the same attributes and values. Each leaf of the classification tree then contains a group of aggregate sets identical to each other insofar as their attribues and values. Groups' members belonging to two sibling leaves (having the same immediate parent) differ from each other in the value of exactly one attribute. Thus, any difference in the worth of sets in those groups can be attributed to that difference. The worth of the aggregate sets in these groups can be averaged when data are noisy. This algorithm works well when applied to real-estate appraisal domain. ©1999 John Wiley & Sons, Inc.     

Penetration and distribution of α-tocopherol, α- or γ-tocotrienols applied individually onto murine skin

To evaluate skin penetration of various vitamin E homologs, a 5% solution of either α-tocopherol, α-tocotrienol, or γ-tocotrienol in polyethylene glycol was topically applied to SKH-1 hairless mice. After 0.5, 1, 2, or 4 h (n=four per time point and four per vitamin E homolog), the skin was washed, the animals killed, the skin rapidlly removed, frozen on dry ice, and a biopsy taken and sectioned: stratum corneum (two uppermost, 5-μm sections—SC1 and SC2), epidermis (next two 10μm sections—E1 and E2), papillary dermis (next 100μ, PD), dermis (next 400 μm, D), and subcutaneous fat (next 100 μm, SF). SC1 contained the highest vitamin E concentrations per μ thickness. To compare the distribution of the various vitamin E forms into the skin layers, the percentage of each form was expressed per its respective total. Most surprising was that the largest fraction of skin vitamin E following topical application was found in the deeper subcutaneous layers—the lowest layers, PD (40±15%) and D (36±15%), contained the major portion of the applied vitamin E forms. Although PD only represents about 16% of the total skin thickness, it contains sebaceous glands—lipid secretory organs, and, thus, may account for the vitamin E affinity for this layer. Hence, applied vitamin E penetrates rapidly through the skin, but the highest concentrations are found in the uppermost 5 microns.