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Biodegradable composite materials represent one of the major areas of investigation for bone tissue engineering due to their tuneable compositional and mechanical properties, which can potentially mimic those of bone and potentially avoid the removal of implants, mitigating the risks for the patient and reducing the overall clinical costs. In addition, the introduction of additive manufacturing technologies enables a strict control over the final morphological features of the scaffolds. In this scenario, the optimisation of 3D printable resorbable composites, made of biocompatible polymers and osteoinductive inorganic phases, offers the potential to produce a chemically and structurally biomimetic implant, which will resorb over time. The present work focuses on the development and process optimisation of two hybrid composite filaments, to be used as feedstock for the fused filament fabrication 3D printing process. A Poly L-lactic acid matrix was blended with either rod-like nano-hydroxyapatite (nano-HA) or nanoparticles of mesoporous bioactive glasses, both partially substituted with strontium (Sr2+), due to the well-known pro-osteogenic effect of this ion. Both inorganic phases were incorporated into Poly L-lactic acid using an innovative combination of processes, obtaining a homogeneous distribution throughout the polymer whilst preserving their ability to release Sr2+. The filament mechanical properties were not hindered after the incorporation of the inorganic phases, resulting in tensile strengths and moduli within the range of cancellous bone, 50 ± 10 MPa and 3 ± 1 GPa. Finally, the rheological characterization of the hybrid composites indicated a shear thinning behaviour, ideal for the processing with fused filament fabrication, proving the potential of these materials to be processed into 3D structures aiming bone regeneration.

This paper reports qualitative data about violence and trauma amongst drug injectors in Scotland, collected using a life story method with 55 drug injectors currently in recovery. It focusses on different types of violence and trauma that occurred whilst using drugs. Stories told of very severe and repeated traumas often involving extreme violence. One motive for escalating and continuing drug use was avoidant coping to deaden the emotions and thoughts regarding these traumas. Many traumas were due partly to the criminal drug milieu, so respondents were in a vicious cycle of using opiates and other sedative drugs to cope with the consequences of being involved in a lifestyle of using, supplying and obtaining illegal sedative drugs. Drugs were used as a dynamic method of self-medication or avoidant coping to cope with life in a criminal milieu. Traumatic events were more often described as worsening the lifestyle than as being motives for quitting. Amongst the traumas recounted were many incidents of extreme violence. Using drugs to block the psychological effects of such traumas may help explain why people persist using opiates despite experiencing evident serious harms. Interventions need to recognise this, be trauma-aware and appreciate that violence and trauma have severe adverse effects on drug injectors even when they are themselves hardened and violent.

We present an experimental and theoretical study of atom-molecule collisions in a mixture of cold, trapped N atoms and NH molecules at a temperature of ∼600  mK. We measure a small N+NH trap loss rate coefficient of k(loss)(N+NH)=9(5)(3)×10(-13)  cm(3) s(-1). Accurate quantum scattering calculations based on ab initio interaction potentials are in agreement with experiment and indicate the magnetic dipole interaction to be the dominant loss mechanism. Our theory further indicates the ratio of N+NH elastic-to-inelastic collisions remains large (>100) into the mK regime.

Background: In North America, there is limited data to support deliberate application strategies for post-graduate residency training. There is significant interest in determining what factors play a role in Canadian medical graduate (CMG) matching to their first choice discipline and heightened concern about the number of students going unmatched altogether. Methods: We analyzed matching outcomes of CMGs based on seven years (2013-2019) of residency application data (n= 13,499) from the Canadian Residency Matching Service (CaRMS) database using descriptive and binary logistic regression modeling techniques. Results: The sample was 54% female, with 60% between the ages of 26 and 29, and 60% attended medical schools in Ontario. Applicants who received more rankings from residency programs were more likely (OR = 1.185, p < 0.001) to match. Higher research activities (OR = 0.985, p < 0.001) and number of applications submitted (OR = 0.920, p < 0.001) were associated with a reduced likelihood of matching. Number of volunteer activities and self-report publications did not significantly affect matching. Being male (OR = 0.799, p < 0.05) aged

Interest in the Scholarship of Teaching and Learning (SoTL) is driven in part by the need to provide systematic academic development for faculty anchored in evidence-based practice such as the introduction of quality assurance frameworks. This article reports on a mixed-method evaluation of one institution’s grassroots multidisciplinary faculty development program, called the Educational Research Series, to determine if it met the needs of its faculty, graduate student, and staff participants. Conducted at one mid-sized university in southern Ontario and framed, as was the program design and implementation, by both adult learning theory and constructivism, the evaluation collected data from session exit surveys, attendee interviews, and facilitator focus groups. The data analysis revealed that reasons for participating included increasing levels of understanding, receiving individual support, and learning about colleagues’ research interests. The major strengths of the program included individual learning, resources, facilitator expertise, interactive sessions, and the multidisciplinary focus. The main challenges centered on depth versus breadth of the sessions, time, and educational language and theory. Participants recommended additional resources, communication among facilitators, institutional recognition, and increased depth of content. As a result of this evaluation, an Advanced Educational Research Series is being offered at the institution. This article will inform other institutions wishing to build SoTL as a field within their institutions.

Digital Light Processing (DLP) stereolithography (SLA) as a high-resolution 3D printing process offers a low-cost alternative for prototyping of microfluidic geometries, compared to traditional clean-room and workshop-based methods. Here, we investigate DLP-SLA printing performance for the production of micro-chamber chip geometries suitable for Polymerase Chain Reaction (PCR), a key process in molecular diagnostics to amplify nucleic acid sequences. A DLP-SLA fabrication protocol for printed micro-chamber devices with monolithic micro-channels is developed and evaluated. Printed devices were post-processed with ultraviolet (UV) light and solvent baths to reduce PCR inhibiting residuals and further treated with silane coupling agents to passivate the surface, thereby limiting biomolecular adsorption occurences during the reaction. The printed devices were evaluated on a purpose-built infrared (IR) mediated PCR thermocycler. Amplification of 75 base pair long target sequences from genomic DNA templates on fluorosilane and glass modified chips produced amplicons consistent with the control reactions, unlike the non-silanized chips that produced faint or no amplicon. The results indicated good functionality of the IR thermocycler and good PCR compatibility of the printed and silanized SLA polymer. Based on the proposed methods, various microfluidic designs and ideas can be validated in-house at negligible costs without the requirement of tool manufacturing and workshop or clean-room access. Additionally, the versatile chemistry of 3D printing resins enables customised surface properties adding significant value to the printed prototypes. Considering the low setup and unit cost, design flexibility and flexible resin chemistries, DLP-SLA is anticipated to play a key role in future prototyping of microfluidics, particularly in the fields of research biology and molecular diagnostics. From a system point-of-view, the proposed method of thermocycling shows promise for portability and modular integration of funcitonalitites for diagnostic or research applications that utilize nucleic acid amplification technology.

Crystallization of 5,17-dibromo-11,27,23,25-tetraone-26,28-dipropoxycalix[4]arene results in the rare observation of two different calix[4]arene conformations (partial cone and 1,3-alternate) co-crystallized within the same single crystal X-ray structure. Analysis using 1H and 13C NMR spectroscopy revealed that only a single conformation (the cone) was present in solution, and in contrast to the structures of other reported calix[4]arenes and calix[4]quinones, both conformations of the compound present in this crystal structure have a “pinched” shape, drastically reducing Br-Br separation and associated cavity sizes.

New approaches are required to access metal-organic assemblies with unusual structural properties. Here, the authors use an in situ redox reaction to obtain a mixed-valence, Mn(II)/Mn(III)-containing metal-organic nanocapsule with an odd number of metal ions.

Calix[n]arenes offer ideal chemical functionality through the polyphenolic lower rim to construct nano-sized coordination clusters with lanthanide (Ln) metal ions (e.g., Nd III10 , Gd III8). However, the number of metal centers they can accommodate is still limited compared to that achievable with smaller ligands (e.g., Gd III140 , Gd III104). Here, we exploit a combination of the "anion template strategy" and "templating ligands" to synthesise three highly symmetric (D3h, trigonal planar) Ln III18 (Ln = La, Nd, and Gd) systems, representing the largest calix[n]arene-based coordination clusters yet. The Ln III18 fragment is templated by a chloride anion located at the center of the cluster, wherefrom twelve μ3-OH− ligands bind 'internally' to the eighteen LnIII ions. 'Externally' the metallic skeleton is connected by p-tert-butylcalix[8]arene, oxo, chloro and carbonate ligands. The crystal packing in the lattice reveals large cylindrical channels of ∼26 Å in diameter, whose pore volume corresponds to ∼50% of the unit cell volume (using a 1.2 Å spherical probe radius). Magnetic measurements reveal the predominance of weak antiferromagnetic exchange in the Gd analog. Heat capacity data of Gd III18 reveal a high magnetic entropy with −ΔSm = 23.7 J K−1 kg−1, indicating potential for engineering magnetic refrigerant materials with calix[8]arenes. [ABSTRACT FROM AUTHOR]

Gender-based violence (GBV) and Domestic Violence (DV) are prevalent in Brazil. There are growing concerns globally regarding the weaponisation of the pseudo-concept 'Parental Alienation' (PA) in the family courts against women. Additionally, a lack of understanding of mothers' family court and health-related experiences indicated a need to explore this topic further. A qualitative study was conducted with thirteen mothers who are victims of Domestic Violence and have been accused of PA. Mothers reported a range of harmful health experiences, delineated here under the conceptual framework of Court and Perpetrator Induced Trauma (CPIT). Six themes are presented, which encapsulate a range of harmful actions, behaviours and circumstances (ABCs) that surround these mothers and their responses to these ABCs. Multiple physical health conditions were reported as associated with family court proceedings. This included maternity problems, musculoskeletal, autoimmune, and respiratory conditions and a broad range of mental health implications including suicide and other trauma responses. Human rights violations, the weaponisation of 'Parental Alienation' and inherently misogynistic and oppressive justice systems in Brazil were also reported. Urgent measures and further research are now needed to investigate causal links between harm to health and the family courts and to strengthen human rights protection for women and child victims in Brazil and beyond. [ABSTRACT FROM AUTHOR]

Recent improvements within the fields of high-throughput screening and 3D tissue culture have provided the possibility of developing in vitro micro-tissue models that can be used to study diseases and screen potential new therapies. This paper reports a proof-of-concept study on the use of microvalve-based bioprinting to create laminar MSC-chondrocyte co-cultures to investigate whether the use of MSCs in ACI procedures would stimulate enhanced ECM production by chondrocytes. Microvalve-based bioprinting uses small-scale solenoid valves (microvalves) to deposit cells suspended in media in a consistent and repeatable manner. In this case, MSCs and chondrocytes have been sequentially printed into an insert-based transwell system in order to create a laminar co-culture, with variations in the ratios of the cell types used to investigate the potential for MSCs to stimulate ECM production. Histological and indirect immunofluorescence staining revealed the formation of dense tissue structures within the chondrocyte and MSC-chondrocyte cell co-cultures, alongside the establishment of a proliferative region at the base of the tissue. No stimulatory or inhibitory effect in terms of ECM production was observed through the introduction of MSCs, although the potential for an immunomodulatory benefit remains. This study, therefore, provides a novel method to enable the scalable production of therapeutically relevant micro-tissue models that can be used for in vitro research to optimise ACI procedures.

Technological pedagogical content knowledge (TPACK) has been well accepted as a framework to understand and describe types of knowledge required by teachers to teach specific content with technology effectively. However, limited studies have used the framework in analysing the complexity of technology integration in mathematics classrooms. This study investigates, through examining critical instructional events, the most influential TPACK constructs in understanding and shaping teachers' pedagogical practices using digital technology. This case study was conducted in an early secondary mathematics classroom in Indonesia that used a web-based resource to support students' understanding of fractions. The finding suggests that the qualitative examination of the four intersected TPACK constructs assists in understanding the challenges and the opportunities to teachers when utilising an exploratory-based technology. It demonstrates that the combination of pedagogical stances and choice of technology significantly influence the visibility of other TPACK constructs. Implications of this study include the need of thoughtful planning prior to using web-based resources and the importance to utilise critical events in developing and assessing teachers' TPACK.