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Understanding factors that affect the clustering and association of antibodies molecules in solution is critical to their development as therapeutics. For 19 different monoclonal antibody (mAb) solutions, we measured the viscosities, the second virial coefficients, the Kirkwood-Buff integrals, and the cluster distributions of the antibody molecules as functions of protein concentration. Solutions were modeled using the statistical-physics Wertheim liquid-solution theory, representing antibodies as Y-shaped molecular structures of seven beads each. We found that high-viscosity solutions result from more antibody molecules per cluster. Multi-body properties such as viscosity are well predicted experimentally by the 2-body Kirkwood-Buff quantity, G22, but not by the second virial coefficient, B22, and well-predicted theoretically from the Wertheim protein-protein sticking energy. Weakly interacting antibodies are rate-limited by nucleation; strongly interacting ones by propagation. This approach gives a way to relate micro to macro properties of solutions of associating proteins.

Protein molecules associate in solution, often in clusters beyond pairwise, leading to liquid phase separations and high viscosities. It is often impractical to study these multi-protein systems by atomistic computer simulations, particularly in multi-component solvents. Instead, their forces and states can be studied by liquid state statistical mechanics. However, past such approaches, such as the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, were limited to modeling proteins as spheres, and contained no microscopic structure-property relations. Recently, this limitation has been partly overcome by bringing the powerful Wertheim theory of associating molecules to bear on protein association equilibria. Here, we review these developments.

We present here a freely available web-based database, called BioMThermDB 1.0, of thermophysical and dynamic properties of various proteins and their aqueous solutions. It contains the hydrodynamic radius, electrophoretic mobility, zeta potential, self-diffusion coefficient, solution viscosity, and cloud-point temperature, as well as the conditions for those determinations and details of the experimental method. It can facilitate the meta-analysis and visualization of data, can enable comparisons, and may be useful for comparing theoretical model predictions with experiments.

Peer-to-peer role-play in social work education continues to have widespread use in the teaching of generalist social work skills. For many students, however, the unfamiliarity of role-playing the client in conjunction with discussing clinical concerns may lead them to become emotionally dysregulated during the social work-client encounter. To explore strategies by which students can maintain emotional regulation when playing the client role, this study garnered the perspectives of Standardized Clients from Canadian medical schools who conduct repeated, simulated performances in the client role. Standardized Clients (N = 116) responded to an online, qualitative survey which explored how they manage their emotions during simulations. Thematic analysis revealed the following regulation strategies: (1) Internal: (a) Distance self from the role, (b) Immerse in the role, (c) Focus on emotions; and (2) External: (a) Putting on a performance, and (b) The importance of self-care. This paper offers suggestions for social work educators to assist students playing the client in peer-to-peer role-play exercises.

How are water's material properties encoded within the structure of the water molecule? This is pertinent to understanding Earth's living systems, its materials, its geochemistry and geophysics, and a broad spectrum of its industrial chemistry. Water has distinctive liquid and solid properties: It is highly cohesive. It has volumetric anomalies-water's solid (ice) floats on its liquid; pressure can melt the solid rather than freezing the liquid; heating can shrink the liquid. It has more solid phases than other materials. Its supercooled liquid has divergent thermodynamic response functions. Its glassy state is neither fragile nor strong. Its component ions-hydroxide and protons-diffuse much faster than other ions. Aqueous solvation of ions or oils entails large entropies and heat capacities. We review how these properties are encoded within water's molecular structure and energies, as understood from theories, simulations, and experiments. Like simpler liquids, water molecules are nearly spherical and interact with each other through van der Waals forces. Unlike simpler liquids, water's orientation-dependent hydrogen bonding leads to open tetrahedral cage-like structuring that contributes to its remarkable volumetric and thermal properties.

As future mandated reporters, social work students face the dual challenge of rendering accurate reporting decisions while concurrently maintaining the therapeutic relationship in an effort to decrease future child abuse and neglect. To address the paucity of training in this regard, 42 bachelor of social work (n=18) and master of social work (n=24) students participated in a workshop focused on decision making and the therapeutic relationship in mandatory reporting of child abuse and neglect. Participants were given a case vignette and responded in writing to structured questions. Two patterns emerged from the qualitative analysis: factors that centered on the case and those that centered on the social worker. Implications for social work education are suggested.

Protein–protein association and aggregation are fundamental processes that play critical roles in various biological phenomena, from cellular signaling to disease progression. Understanding the underlying biophysical principles governing these processes is crucial for elucidating their mechanisms and developing strategies for therapeutic intervention. In this review, we provide an overview of recent experimental studies focused on protein–protein association and aggregation. We explore the key biophysical factors that influence these processes, including protein structure, conformational dynamics, and intermolecular interactions. We discuss the effects of environmental conditions such as temperature, pH and related buffer-specific effects, and ionic strength and related ion-specific effects on protein aggregation. The effects of polymer crowders and sugars are also addressed. We list the techniques used to study aggregation. We analyze emerging trends and challenges in the field, including the development of computational models and the integration of multidisciplinary approaches for a comprehensive understanding of protein–protein association and aggregation. [ABSTRACT FROM AUTHOR]

Protein aggregation is broadly important in diseases and in formulations of biological drugs. Here, we develop a theoretical model for reversible protein-protein aggregation in salt solutions. We treat proteins as hard spheres having square-well-energy binding sites, using Wertheim's thermodynamic perturbation theory. The necessary condition required for such modeling to be realistic is that proteins in solution during the experiment remain in their compact form. Within this limitation our model gives accurate liquid-liquid coexistence curves for lysozyme and γ IIIa-crystallin solutions in respective buffers. It provides good fits to the cloud-point curves of lysozyme in buffer-salt mixtures as a function of the type and concentration of salt. It than predicts full coexistence curves, osmotic compressibilities, and second virial coefficients under such conditions. This treatment may also be relevant to protein crystallization.

To strengthen students' preparation for engaging in field learning, an innovation was implemented to teach and assess foundation-year students' performance prior to entering field education. An Objective Structured Clinical Examination informed the final evaluation of students' performance in two companion courses on practice theory and skills. The evaluation was used by field instructors and students to develop the field learning plan. This article reports on a qualitative study that examined field instructors' and faculty field liaisons' experiences and reactions to using this new approach and its impact in shaping students' field learning goals. Implications for supporting adoption of innovations that strengthen the link between classroom and field teaching are offered, including new institutional policies that resulted from ongoing evaluation.

Researchers explored patterns of significance in students' reflective writings before and after interviews with individuals unlike themselves. To determine changes in cultural attitudes or beliefs, the Linguistic Inquiry Word Count (LIWC) program and QUAN [right arrow]qual sequential mixed methods model was used. Seven factors explained 66.49% of the variance. This is a successful replication of a previous study, so the authors describe specific contextual differences. An analysis of participants' reflective writings offer insight about how participants integrate new and existing knowledge. Thematic content of the qualitative data revealed that increased opportunities for contact resulted in students' expressions of change. The findings demonstrate that experiencing instructional activities which challenge dental students' personal biases, while simultaneously exposing them first hand to the lived realities of others is important to catalyzing a shift in attitudes. Based on these findings, experiential learning experiences versus didactic coursework are recommended for students to relate the concepts of cultural competency and health disparities. Mixed methods inquiry can inform faculty about the outcomes that may emerge from these efforts.

Water is an unusual liquid in its solvation properties. Here, we model the process of transferring a nonpolar solute into water. Our goal was to capture the physical balance between waters hydrogen bonding and van der Waals interactions in a model that is simple enough to be nearly analytical and not heavily computational. We develop a 2-dimensional Mercedes-Benz-like model of water with which we compute the free energy, enthalpy, entropy, and the heat capacity of transfer as a function of temperature, pressure, and solute size. As validation, we find that this model gives the same trends as Monte Carlo simulations of the underlying 2D model and gives qualitative agreement with experiments. The advantages of this model are that it gives simple insights and that computational time is negligible. It may provide a useful starting point for developing more efficient and more realistic 3D models of aqueous solvation.