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Volumetric Additive Manufacturing (VAM) represents a revolutionary advancement in the field of Additive Manufacturing, as it allows for the creation of objects in a single, cohesive process, rather than in a layer-by-layer approach. This innovative technique offers unparalleled design freedom and significantly reduces printing times. A current limitation of VAM is the availability of suitable resins with the required photoreactive chemistry and from sustainable sources. To support the application of this technology, we have developed a sustainable resin based on polyglycerol, a bioderived (e.g., vegetable origin), colourless, and easily functionisable oligomer produced from glycerol. To transform polyglycerol-6 into an acrylate photo-printable resin we adopted a simple, one-step, and scalable synthesis route. Polyglycerol-6-acrylate fulfils all the necessary criteria for volumetric printing (transparency, photo-reactivity, viscosity) and was successfully used to print a variety of models with intricate geometries and good resolution. The waste resin was found to be reusable with minimal performance issues, improving resin utilisation and minimising waste material. Furthermore, by incorporating dopants such as poly(glycerol) adipate acrylate (PGA-A) and 10,12-pentacosadyinoic acid (PCDA), we demonstrated the ability to print objects with a diverse range of functionalities, including temperature sensing probes and a polyester excipient, highlighting the potential applications of these new resins. [ABSTRACT FROM AUTHOR]

Polymersomes are an exciting modality for drug delivery due to their structural similarity to biological cells and their ability to encapsulate both hydrophilic and hydrophobic drugs. In this regard, the current work aimed to develop multifunctional polymersomes, integrating dye (with hydrophobic Nile red and hydrophilic sulfo-cyanine5-NHS ester as model drugs) encapsulation, stimulus responsiveness, and surface-ligand modifications. Polymersomes constituting poly(N-2-hydroxypropylmethacrylamide)-b-poly(N-(2-(methylthio)ethyl)acrylamide) (PHPMAm-b-PMTEAM) are prepared by aqueous dispersion RAFT-mediated polymerization-induced self-assembly (PISA). The hydrophilic block lengths have an effect on the obtained morphologies, with short chain P(HPMAm)16 affording spheres and long chain P(HPMAm)43 yielding vesicles. This further induces different responses to H2O2, with spheres fragmenting and vesicles aggregating. Folic acid (FA) is successfully conjugated to the P(HPMAm)43, which self-assembles into FA-functionalized P(HPMAm)43-b-P(MTEAM)300 polymersomes. The FA-functionalized P(HPMAm)43-b-P(MTEAM)300 polymersomes entrap both hydrophobic Nile red (NR) and hydrophilic Cy5 dye. The NR-loaded FA-linked polymersomes exhibit a controlled release of the encapsulated NR dye when exposed to 10 mM H2O2. All the polymersomes formed are stable in human plasma and well-tolerated in MCF-7 breast cancer cells. These preliminary results demonstrate that, with simple and scalable chemistry, PISA offers access to different shapes and opens up the possibility of the one-pot synthesis of multicompartmental and responsive polymersomes. [ABSTRACT FROM AUTHOR]

Biomechanical cues from the extracellular matrix (ECM) are essential for directing many cellular processes, from normal development and repair, to disease progression. To better understand cell-matrix interactions, we have developed a new instrument named 'OptoRheo' that combines light sheet fluorescence microscopy with particle tracking microrheology. OptoRheo lets us image cells in 3D as they proliferate over several days while simultaneously sensing the mechanical properties of the surrounding extracellular and pericellular matrix at a sub-cellular length scale. OptoRheo can be used in two operational modalities (with and without an optical trap) to extend the dynamic range of microrheology measurements. We corroborated this by characterising the ECM surrounding live breast cancer cells in two distinct culture systems, cell clusters in 3D hydrogels and spheroids in suspension culture. This cutting-edge instrument will transform the exploration of drug transport through complex cell culture matrices and optimise the design of the next-generation of disease models. A new instrument named OptoRheo combines light sheet fluorescence microscopy and particle tracking microrheology for live imaging and micromechanical sensing of extracellular matrix-cell interactions. [ABSTRACT FROM AUTHOR]

This article constructs a genealogy of three poetic sports documentaries, all of which use multiple cameras to isolate a star athlete for the duration of a team game. All three films are defined by their distinction from dominant forms of coverage, which allows them to foreground elements of the spectacle typically marginalized by the standard grammar and narratives of sports media. These films play on the boundary between sports coverage and documentary in order to develop a richer and more nuanced analysis of sports aesthetics. [ABSTRACT FROM AUTHOR]

Abstract: The self‐assembly of specific polymers into well‐defined nanoparticles (NPs) is of great interest to the pharmaceutical industry as the resultant materials can act as drug delivery vehicles. In this work, a high‐throughput method to screen the ability of polymers to self‐assemble into NPs using a picoliter inkjet printer is presented. By dispensing polymer solutions in dimethyl sulfoxide (DMSO) from the printer into the wells of a 96‐well plate, containing water as an antisolvent, 50 suspensions are screened for nanoparticle formation rapidly using only nanoliters to microliters. A variety of polymer classes are used and in situ characterization of the submicroliter nanosuspensions shows that the particle size distributions match those of nanoparticles made from bulk suspensions. Dispensing organic polymer solutions into well plates via the printer is thus shown to be a reproducible and fast method for screening nanoparticle formation which uses two to three orders of magnitude less material than conventional techniques. Finally, a pilot study for a high‐throughput pipeline of nanoparticle production, physical property characterization, and cytocompatibility demonstrates the feasibility of the printing approach for screening of nanodrug delivery formulations. Nanoparticles are produced in the well plates, characterized for size and evaluated for effects on metabolic activity of lung cancer cells. [ABSTRACT FROM AUTHOR]

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This study employed the capabilities-expectations model of engagement in classroom learning based on bio-ecological frameworks of intellectual development and flow theory. According to the capabilities-expectations model, engagement requires a balance between the capabilities of a student for learning in a particular situation and what is expected of that student's learning. The study also used an eight-element model of the classroom learning environment (self educational values, self learning outcomes, classroom/peer learning attitudes and behaviours, classroom/peer support, classroom/peer discussion, classroom planning, teacher support and expectations, and parental involvement). The aim was to test the assumption that engagement in classroom learning and perceptions of the classroom learning environment both indicate the same uni-dimensional construct. If this assumption is correct, then it should be possible to plot measures of student engagement and measures of the learning environment on the same linear scale. A measurement model such as the Rasch Model can then be used to test how well empirical data fit the scale. An 85-item rating scale survey of student engagement in classroom learning and the classroom learning environment scale was created. Data from its administration to 1760 secondary school students were tested for fit to the Rasch Rating Scale Model. Data on engagement in classroom learning and the classroom learning environment were able to be plotted on one interval scale, therefore suggesting the presence of the underlying common construct. The construct was called an engaging learning environment. [ABSTRACT FROM AUTHOR]

The psychometric properties of the General Functioning subscale of the McMaster Family Assessment Device were examined using the Rasch Model (N = 237 couples). Mothers’ and fathers’ ratings of the General Functioning subscale of the McMaster Family Assessment Device are recommended, provided these are analyzed separately. More than a quarter of couples differed significantly in their ratings. [ABSTRACT FROM PUBLISHER]

The article examines theoretical issues associated with measurement in the human sciences and ensuring data from rating scale instruments are measures. An argument is made that using raw scores from rating scale instruments for subsequent arithmetic operations and applying linear statistics is less preferable than using measures. These theoretical matters are then illustrated by a report on the application of the Rasch Rating Scale Model in an investigation into elementary school classroom learning culture. [ABSTRACT FROM AUTHOR]

The study was grounded on theoretical propositions and empirical research concerning school effectiveness, classroom effectiveness, school improvement and school renewal. In particular, improving student learning outcomes through improving and renewing schools is dependent on changing classroom cultures of learning and teaching. A model of classroom culture consisting of student educational values (dependent variable), formal learning outcomes (dependent variable), and the attitudes and behaviours of students, teachers and parents (independent variables) was proposed. Hypothesised relationships between the dependent and independent variables were tested by multiple regression analysis of data from 988 students obtained from administration of a Rasch-model instrument assessing classroom culture. The classroom learning attitudes and behaviours of students were found to relate directly to educational outcomes, as were teacher expectations and parent attitudes and behaviours. The attitudes and behaviours of students and teachers towards classroom collaboration and caring were not confirmed to relate directly to learning outcomes. The findings of the investigation are discussed in the light of the theoretical assumptions upon which the study was based, including identification of the implications of the empirical results for understanding and facilitating renewal of secondary schools with the intention of improving educational outcomes in classrooms. [ABSTRACT FROM AUTHOR]

The article presents a discussion on school leadership issue and changing teachers' pedagogic practices. In particular, it identifies the key factors in bringing about pedagogic change by concluding with proposal of a conceptual framework of pedagogic leadership. Most schools are characterized by a combination of formal and informal leadership as evidenced by teachers assuming responsibility for particular tasks and programmes. While the concept of instructional leadership provided well-needed recognition of the importance of teaching and learning in schools, its application in understanding leadership of pedagogic change is difficult to justify. Although the leadership of schools is a complex phenomenon, the outcomes of successful school leadership are readily identifiable.

This study investigated parent-reported receptivity towards the classroom environment and classroom outcomes. Classroom environment was based on a five-aspect model: (1) provision of information from the child; (2) beliefs about the school; (3) provision of information from teachers; (4) teachers' commitment to working with parents; and (5) confidence in communicating with teachers. Classroom outcomes were based on two aspects: (1) educational values (importance of schooling, involved with learning; seeing a future through learning, desire to learn, and importance of learning); and (2) learning outcomes (achieving, and views of child's engagement in school work). For each aspect, items were written in an ordered-by-difficulty pattern so that, for example, Item 2 involved Item 1 and ‘more’, making it conceptually ‘harder’ to agree with Item 2 than with Item 1. There were four Likert response categories (SDA, DA, A, and SA). Using the extended logistic model of Rasch, an interval-level, unidimensional scale was created with item difficulties for classroom environment aspects and classroom outcomes calibrated on the same scale as the receptivity measures. The sample consisted of 518 parents of students from three secondary schools in Western Australia. The item sample was 30. The proportion of observed variance considered true was 0.94. The items for each aspect were found to be ordered from ‘easy’ to ‘hard’ in line with the hypothesised model of receptivity and the data fitted the measurement model well. [ABSTRACT FROM AUTHOR]

This study examined the subject‐choice process engaged in by a sample of Western Australian school students. The theoretical background was provided by career education models in which aspects of cognitive preferences are related to the choice of particular science and mathematics subjects. CareerMate, a computerised career counselling instrument, was used to identify cognitive preferences in the four dimensions of energy projection, experience preference, helping and closure. Aspects of the students’ preferences were correlated with their subject choices and gender and subject specific relationships emerged. There were significant differences in cognitive preferences between the academically capable females who chose matriculation physical science and mathematics subjects and those who did not. These differences need to be considered when encouraging females to select such subjects. If these subjects are to attract capable females currently choosing alternatives, then changes to the curriculum content and teaching approach should also be considered. [ABSTRACT FROM PUBLISHER]

Glioblastoma (GBM) is the most common, malignant and aggressive brain tumour in adults. Despite the use of multimodal treatments, involving surgery, followed by concomitant radiotherapy and chemotherapy, the median survival for patients remains less than 15 months from diagnosis. Low penetration of drugs across the blood-brain barrier (BBB) is a dose-limiting factor for systemic GBM therapies, and as a result, post-surgical intracranial drug delivery strategies are being developed to ensure local delivery of drugs within the brain. Here we describe the effects of PEGylated poly(lactide)-poly(carbonate)-doxorubicin (DOX) nanoparticles (NPs) on the metabolic activity of primary cancer cell lines derived from adult patients following neurosurgical resection, and the commercially available GBM cell line, U87. The results showed that non-drug-loaded NPs were well tolerated at concentrations of up to 100 µg/mL while tumour cell-killing effects were observed for the DOX-NPs at the same concentrations. Further experiments evaluated the release of DOX from polymer-DOX conjugate NPs when incorporated in a thermosensitive in situ gelling poly(DL-lactic-co-glycolic acid) and poly(ethylene glycol) (PLGA/PEG) matrix paste, in order to simulate the clinical setting of a locally injected formulation for GBM following surgical tumour resection. These assays demonstrated drug release from the polymer pro-drugs, when in PLGA/PEG matrices of two formulations, over clinically relevant time scales. These findings encourage future in vivo assessment of the potential capability of polymer–drug conjugate NPs to penetrate brain parenchyma efficaciously, when released from existing interstitial delivery systems. [ABSTRACT FROM AUTHOR]

Biocompatible and bio-based materials are an appealing resource for the pharmaceutical industry. Poly(glycerol-adipate) (PGA) is a biocompatible and biodegradable polymer that can be used to produce self-assembled nanoparticles (NPs) able to encapsulate active ingredients, with encouraging perspectives for drug delivery purposes. Starch is a versatile, inexpensive, and abundant polysaccharide that can be effectively applied as a bio-scaffold for other molecules in order to enrich it with new appealing properties. In this work, the combination of PGA NPs and starch films proved to be a suitable biopolymeric matrix carrier for the controlled release preparation of hydrophobic drugs. Dynamic Light Scattering (DLS) was used to determine the size of drug-loaded PGA NPs, while the improvement of the apparent drug water solubility was assessed by UV-vis spectroscopy. In vitro biological assays were performed against cancer cell lines and bacteria strains to confirm that drug-loaded PGA NPs maintained the effective activity of the therapeutic agents. Dye-conjugated PGA was then exploited to track the NP release profile during the starch/PGA nanocomposite film digestion, which was assessed using digestion models mimicking physiological conditions. The collected data provide a clear indication of the suitability of our biodegradable carrier system for oral drug delivery. [ABSTRACT FROM AUTHOR]

Starch is one of the most abundant polysaccharides on the earth and it is the most important source of energy intake for humans. Thermoplastic starch (TPS) is also widely used for new bio-based materials. The blending of starch with other molecules may lead to new interesting biodegradable scaffolds to be exploited in food, medical, and pharmaceutical fields. In this work, we used native starch films as biopolymeric matrix carriers of chemo enzymatically-synthesized poly (glycerol-adipate) (PGA) nanoparticles (NPs) to produce a novel and biocompatible material. The prototype films had a crystallinity ranging from 4% to 7%. The intrinsic and thermo-mechanical properties of the composite showed that the incorporation of NPs in the starch films decreases the glass transition temperature. The utilization of these film prototypes as the basis for new biocompatible material showed promise, particularly because they have a very low or even zero cytotoxicity. Coumarin was used to monitor the distribution of the PGA NPs in the films and demonstrated a possible interaction between the two polymers. These novel hybrid nanocomposite films show great promise and could be used in the future as biodegradable and biocompatible platforms for the controlled release of amphiphilic and hydrophobic active ingredients. [ABSTRACT FROM AUTHOR]

Permeability enhancers are receiving increased attention arising from their ability to increase transepithelial permeability and thus, bioavailability of orally or pulmonary administered biopharmaceutics. Here we present the synthesis and the in vitro assaying of a series of lactose-based non-ionic surfactants, highlighting the relationship between their structure and biological effect. Using tensiometric measurements the critical micelle concentrations (CMCs) of the surfactants were determined and demonstrate that increasing hydrophobic chain length reduces surfactant CMC. In vitro testing on Caco-2 intestinal and Calu-3 airway epithelia revealed that cytotoxicity, assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) release assays, is presented for most of the surfactants at concentrations greater than their CMCs. Further biological study demonstrates that application of cytotoxic concentrations of the surfactants is associated with depolarizing mitochondrial membrane potential, increasing nuclear membrane permeability and activation of effector caspases. It is, therefore, proposed that when applied at cytotoxic levels, the surfactants are inducing apoptosis in both cell lines tested. Importantly, through the culture of epithelial monolayers on Transwell® supports, the surfactants demonstrate the ability to reversibly modulate transepithelial electrical resistance (TEER), and thus open tight junctions, at non-toxic concentrations, emphasizing their potential application as safe permeability enhancers in vivo. [ABSTRACT FROM AUTHOR]