Perceptions of helpfulness in conjoint behavioral consultation: Congruence and agreement between teachers and parents.

Conjoint behavioral consultation (CBC) can be considered a help-giving model, wherein consultants work with parents and teachers in an effort to develop constructive partnerships aimed at addressing needs of students for whom both parties share responsibility. The development of strong relationships among systems in a child's life is related to positive outcomes for children, and congruence among systems is one relationship variable that has received previous research attention. This study examined the degree to which parent and teacher perceptions of the helpfulness of the CBC consultant are congruent, and its relationship with various case outcomes. Correlational analyses suggest that parents' and teachers' perspectives of the helpfulness of the consultant are not necessarily related to each other, and as differences increase, perceptions of outcomes decrease for both parties. Research implications, limitations, and future directions are offered. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Nanocellulose as a natural source for groundbreaking applications in materials science: Today’s state

Nanocelluloses are natural materials with at least one dimension in the nano-scale. They combine important cellulose properties with the features of nanomaterials and open new horizons for materials science and its applications. The field of nanocellulose materials is subdivided into three domains: biotechnologically produced bacterial nanocellulose hydrogels, mechanically delaminated cellulose nanofibers, and hydrolytically extracted cellulose nanocrystals. This review article describes today’s state regarding the production, structural details, physicochemical properties, and innovative applications of these nanocelluloses. Promising technical applications including gels/foams, thickeners/stabilizers as well as reinforcing agents have been proposed and research from last five years indicates new potential for groundbreaking innovations in the areas of cosmetic products, wound dressings, drug carriers, medical implants, tissue engineering, food and composites. The current state of worldwide commercialization and the challenge of reducing nanocellulose production costs are also discussed.     

Experiences of First‐Year Engineering Students Working on Ill‐Structured Problems in Teams

Background

As engineers solve problems that are ill‐structured and require collaboration, a common goal of engineering programs is to develop students' competencies for solving such problems in teams, often using cornerstone design experiences.

Purpose

With the goal of designing effective learning environments, this study identifies qualitatively different ways that engineering students experienced ill‐structured problems while working in teams.

Design/Method

This phenomenographic study employs interview data from 27 first‐year engineering students. Iterative data analysis resulted in categories of student experiences and their logical relationships.

Results

Seven categories describing collaborative, ill‐structured problem‐solving experiences emerged: completion, transition, iteration, organization, collaboration, reasoning, and growth. These categories are organized in an outcome space along dimensions we call reaction to ambiguity and use of multiple perspectives that can be used to frame students' perspectives from less comprehensive to more comprehensive.

Conclusions

First‐year engineering students experience team‐based, ill‐structured problem solving in a variety of ways. The resulting outcome space is of practical use to educators who teach courses involving collaborative, ill‐structured problem solving.     

Super‐Strong,Super‐Stiff Macrofibers with Aligned,Long Bacterial Cellulose Nanofibers

With their impressive properties such as remarkable unit tensile strength, modulus, and resistance to heat, flame, and chemical agents that normally degrade conventional macrofibers, high‐performance macrofibers are now widely used in various fields including aerospace, biomedical, civil engineering, construction, protective apparel, geotextile, and electronic areas. Those macrofibers with a diameter of tens to hundreds of micrometers are typically derived from polymers, gel spun fibers, modified carbon fibers, carbon‐nanotube fibers, ceramic fibers, and synthetic vitreous fibers. Cellulose nanofibers are promising building blocks for future high‐performance biomaterials and textiles due to their high ultimate strength and stiffness resulting from a highly ordered orientation along the fiber axis. For the first time, an effective fabrication method is successfully applied for high‐performance macrofibers involving a wet‐drawing and wet‐twisting process of ultralong bacterial cellulose nanofibers. The resulting bacterial cellulose macrofibers yield record high tensile strength (826 MPa) and Young's modulus (65.7 GPa) owing to the large length and the alignment of nanofibers along fiber axis. When normalized by weight, the specific tensile strength of the macrofiber is as high as 598 MPa g^?1 cm³, which is even substantially stronger than the novel lightweight steel (227 MPa g^?1 cm³).     

Advances in targeted nanotherapeutics: From bioconjugation to biomimicry

Since the emergence of cancer nanomedicine, researchers have had intense interest in developing nanoparticles (NPs) that can specifically target diseased sites while avoiding healthy tissue to mitigate the off-target effects seen with conventional treatments like chemotherapy. Initial endeavors focused on the bioconjugation of targeting agents to NPs, and more recently, researchers have begun to develop biomimetic NP platforms that can avoid immune recognition to maximally accumulate in tumors. In this review, we describe the advantages and limitations of each of these targeting strategies. First, we review developments in bioconjugation strategies, where NPs are coated with biomolecules such as antibodies, aptamers, peptides, and small molecules to enable cell-specific binding. While bioconjugated NPs offer many exciting features and have improved pharmacokinetics and biodistribution relative to unmodified NPs, they are still recognized by the body as “foreign”, resulting in their clearance by the mononuclear phagocytic system (MPS). To overcome this limitation, researchers have recently begun to investigate biomimetic approaches that can hide NPs from immune recognition and reduce clearance by the MPS. These biomimetic NPs fall into two distinct categories: synthetic NPs that present naturally occurring structures, and NPs that are completely disguised by natural structures. Overall, bioconjugated and biomimetic NPs have substantial potential to improve upon conventional treatments by reducing off-target effects through site-specific delivery, and they show great promise for future standards of care. Here, we provide a summary of each strategy, discuss considerations for their design moving forward, and highlight their potential clinical impact on cancer therapy.     

Continuous Flow Deformability‐Based Separation of Circulating Tumor Cells Using Microfluidic Ratchets

Circulating tumor cells (CTCs) offer tremendous potential for the detection and characterization of cancer. A key challenge for their isolation and subsequent analysis is the extreme rarity of these cells in circulation. Here, a novel label‐free method is described to enrich viable CTCs directly from whole blood based on their distinct deformability relative to hematological cells. This mechanism leverages the deformation of single cells through tapered micrometer scale constrictions using oscillatory flow in order to generate a ratcheting effect that produces distinct flow paths for CTCs, leukocytes, and erythrocytes. A label‐free separation of circulating tumor cells from whole blood is demonstrated, where target cells can be separated from background cells based on deformability despite their nearly identical size. In doping experiments, this microfluidic device is able to capture >90% of cancer cells from unprocessed whole blood to achieve 10⁴‐fold enrichment of target cells relative to leukocytes. In patients with metastatic castration‐resistant prostate cancer, where CTCs are not significantly larger than leukocytes, CTCs can be captured based on deformability at 25× greater yield than with the conventional CellSearch system. Finally, the CTCs separated using this approach are collected in suspension and are available for downstream molecular characterization.     

Garnet/polymer hybrid ion-conducting protective layer for stable lithium metal anode

Rechargeable Li metal batteries using Li metal anodes have attracted worldwide interest because of their high energy density. The critical barriers limiting their commercial application include uncontrolled dendritic Li growth and the unstable Li–electrolyte interface. Considerable efforts have been directed towards solving these problems, e.g., modifying the electrolyte, creating artificial interfacial layers for the Li metal, and constructing three-dimensional structures for the Li metal. However, stabilizing the Li metal interface remains challenging because of the highly reactive nature of the Li metal. In this study, we utilize a Li-ion conducting hybrid film comprising a garnet-type ion conductor and a poly(ethylene oxide)-based polymer electrolyte as a protective layer to stabilize the Li–electrolyte interface and mitigate the growth of Li dendrites. The hybrid ion-conducting layer can block Li dendrites from proliferating and accommodate Li volume expansion because of its robust mechanical properties. Moreover, the ion-conducting layer allows Li deposition only underneath it, rather than on the surface, functioning as a permanent protective layer to ensure the stability of the Li metal over a long cycling life. The dendrite-inhibiting effect of the ion-conducting protective layer is visually evidenced by in situ microscopy using planar batteries. The protective Li metal anode exhibits excellent cycling stability and low voltage hysteresis (～15 mV at 0.2 mA·cm^–2) for a cycle life as long as 1,000 h. It also shows a high Coulombic efficiency (～99.5%) in a full cell against a LiFePO₄ cathode, exhibiting promise for application in Li metal batteries. Our results imply that the ion-conducting protective layer markedly improves the metal anode, yielding safe, long-life, and high-energy-density batteries.

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