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In recent years, aerogels have received more and more attention from researchers due to their properties such as low density, high porosity, high specific surface area and low thermal conductivity. Polysaccharide-based aerogel is a solid porous nanomaterial with three-dimensional network structure prepared by using polysaccharide as the precursor material and transforming the liquid phase in the gel with gas phase through a drying method. In addition to the characteristics of traditional aerogel materials, polysaccharide-based aerogels also have the advantages of non-toxicity, easy availability of raw materials, biocompatibility and biodegradability. This article summarizes the preparation methods of polysaccharide-based aerogels, and reviews the properties and applications of different types of polysaccharide-based aerogels prepared with different precursor materials, so as to provide a reference for the research and application of polysaccharide-based aerogel materials in food packaging.

Cellulose is commonly acknowledged as a sustainable material owing to its abundance and renewability. However, the abundance of hydroxyl groups makes the paper material highly hydrophilic, and the hydrogen bonds between the fibers are easily broken by water, leading to the degradation of mechanical properties. This work details the fabrication of a composite paper comprising interwoven cellulose and polylactic acid (PLA) structures through hot‐pressing and PLA impregnation onto handwritten paper derived from conventional wood pulp fibers as the substrate. The investigation assessed how varying PLA concentrations influenced the overall characteristics of the composite paper, including its morphology, structure, mechanical properties, water absorption behavior, and water contact angle. Experimental results revealed that the composite paper fabricated through our approach exhibited an intertwined structure comprising both PLA and cellulose. With a tensile index reaching 33.24 kN·m/kg and a mere 31.1% loss in tensile index post‐water treatment, the mechanical properties of the composite paper were significantly enhanced due to the robust interfacial compatibility between cellulose and PLA, as well as the adhesive effect of PLA. Furthermore, the composite paper (CP) is easily processable and amenable to thermoforming into paper trays as required, indicative of its potential applications in the packaging industry. [ABSTRACT FROM AUTHOR]

When reading scientific text, readers must draw inferences when the author does not make relations explicit; readers also need to pick up on causal relations that the author "does" make explicit. We collected think-aloud protocols from 86 undergraduate biology students reading 7 brief, illustrated passages about the immune system. After reading, participants typed a free recall. Both think-aloud and recall were transcribed and coded for two types of causal language--specific action verbs and explicit causal terms (forms of the word "cause")--as well as inferences. Inferences in recalls were significantly related to action verbs picked up and during reading, as evidenced by the think-alouds. Action verbs in recalls were significantly facilitated by inferences and pick up of action verbs articulated by the participants while reading, as evidenced by the think-alouds. Explicit causal terms in recalls were significantly facilitated by pick up of action verbs while reading. Results suggest a very important role for pick-up of specific action verbs while reading, and risks associated with learners substituting vague verbs of class membership ("is a," "has a") for highly specific action verbs ("activates," "binds") when learning biology. One possible implication is that prompting students to pick up on specific action verbs while reading biology texts--in addition to making inferences during reading--could prompt more benefit from reading these types of texts.

Stakeholders are increasingly calling for improving instruction in STEM by building environments that enable faculty to sustainably change their teaching practices. This study reports one institutional change effort that effectively facilitated faculty's adoption of evidence-based instructional practices (EBIP), which is to organize faculty into teaching-focused communities of practice (CoPs). We examined the social interactions of faculty within CoPs and investigated whether faculty in CoPs that were actively adopting EBIP (adopting CoPs) had more frequent conversations and collaborations around teaching with their colleagues than faculty in CoPs that did not adopt EBIP (non-adopting CoPs). A sociometric survey was administered to document 89 faculty members' social interactions within 22 CoPs. The social networks of the CoPs were compared using the social network measures of density, connectedness, centrality, breadth, and reciprocity. We found that adopting CoPs had higher density and connectedness than non-adopting CoPs while being less centralized. This result suggests that adopting CoPs used distributed leadership and included all members in communications regarding teaching, while non-adopting CoPs heavily relied on a lone hero to implement change, frequently excluding other members. These findings suggest that organizing faculty into CoPs that support regular interaction on teaching-related activities may be an effective strategy for improving STEM instruction.

Cellulose foam, renowned for its lightweight properties and exceptional adsorption capacity, has emerged as a significant material of interest. In our study, a distinct functionalized cellulose foam adsorbent was developed using N,N‐methylenebisacrylamide (MBA) as a cross‐linker. This foam was further chemically tailored with 3‐aminopropyltriethoxysilane (APTES) and tannic acid (TA) to optimize its affinity for Cu (II). Utilizing a green and efficient procedure at ambient temperature, MBA was directly crosslinked with MCC sol, the resultant foam features a distinguished three‐dimensional, multi‐walled porous configuration, marked by a strikingly low average density of 0.0306 g/cm3 and an impressive average porosity surpassing 97%. Subsequently, more amino and oxygen‐containing groups were introduced by simple impregnation. The rich functional groups and unique structure enabled the adsorption of Cu (II) up to 93 mg/g, demonstrating an increasing trend in line with rising Cu (II) concentrations. Furthermore, this composite cellulose foam displayed commendable hydrophobic characteristics, evident from a hydrophobic angle surpassing 120°. From both environmental and economic perspectives, this chemically‐modified cellulose material epitomizes an ideal adsorbent, showcasing unparalleled adsorption capacity coupled with robust chemical and structural integrity. As such, it presents a viable option for the efficient sequestration of Cu (II) in wastewater treatments. [ABSTRACT FROM AUTHOR]

Instructional influences on productive use of academic vocabulary were investigated among 460 mostly African American and Latina/o fifth graders from 36 classrooms in eight public schools serving low-income families. Students received a 6-week unit on wolf management involving collaborative group work (CG) or direct instruction (DI). The big question that students tried to answer during the unit was whether a community should be permitted to destroy a pack of wolves. In an individual oral interview about an analogue to the wolf question, whether whaling should be allowed, both CG and DI students used more general and domain-specific academic vocabulary from the Wolf Unit than uninstructed control students. CG students used more general academic vocabulary in the whale interview than DI students, and this was mediated by the CG students' greater use of general academic vocabulary in classroom dialogue during the Wolf Unit. These results suggest that CG is an effective instructional approach to promote acquisition and productive use of academic vocabulary for children from underserved communities.

This research examined the influence of contrasting instructional approaches on children's decision-making competence. A total of 764 fifth graders, mostly African Americans and Hispanic Americans, from 36 classrooms in eight public schools serving children from low-income families completed a six-week unit on wolf management, using either direct instruction or collaborative groups, or were waited-listed controls. Analysis of children's essays on a topic unrelated to wolves revealed that students who participated in collaborative groups but not students who received direct instruction acquired decision-making strategies and transferred them to the novel task. Students in collaborative group work classrooms wrote essays that were significantly better than essays of students from direct instruction classrooms in each of the three aspects of decision making that were evaluated--considering more than one side of a dilemma, comprehensiveness of reasons, and weighing the importance of reasons. In contrast, direct instruction students performed no better than uninstructed control students.