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Lattice Structures for Bone Replacement: The Intersection of Bone Biomechanics, Lattice Design, and Additive Manufacturing
Get PDFAdditive manufacturing (AM) has enabled the development of highly porous orthopedic implants by incorporating lattice structures that mimic the micro‐architecture of natural bone. Lattices can be tuned to replicate bone's mechanical properties, creating implants that preserve the bone environment and allow bone formation within lattice pores. This review examines the intersection of bone biology, lattice design, and AM technologies to guide the development of such biomimetic structures. The hierarchical structure, mechanical properties, anisotropy, and heterogeneity of bone are identified as critical factors influencing bone remodeling, which is regulated by mechanical stimuli and can inform lattice design. Lattice mechanical behavior can be tailored through base material, relative density, topology, anisotropy, and size, which in turn affect biological responses, including cell function, tissue growth, and vascularization. Among available AM methods, powder bed fusion demonstrates the greatest capacity for producing complex geometries with high precision and reproducibility. Post‐processing techniques, such as surface and thermal treatments and biomimetic coatings, are increasingly recognized as crucial for enhancing mechanical and biological performance. Still, current clinical and preclinical applications underscore remaining challenges in improving fatigue life, implant stabilization, vascularization, and bioactivity. This review provides a framework for advancing the design and clinical translation of lattice‐based orthopedic implants
Factors associated with hormone replacement therapy use: a systematic review and meta-analysis
Get PDFObjective: To identify factors associated with HRT uptake among women.
Design: A systematic review and meta-analysis to identify factors associated with HRT uptake.
Setting: Retrospective and prospective cohort studies, case-control studies and crosssectional from any country and in any language.
Population: The study population was women aged 40-60 years old.
Methods :We searched Medline, Embase, CINAHL and Cochrane databases to identify studies reporting associations between demographic, behavioural, or healthrelated factors and HRT uptake. Studies were selected if they reported numbers or odds ratios of the factors and HRT uptake. Studies were combined for metaanalysis, reporting odds ratios and 95% confidence intervals. Quality assessment was performed to quantify the risk of bias.
Main outcome measures: HRT uptake, defined as “ever” versus “never” users.
Results: 5,124 papers were identified for title and abstract screening; 136 full texts were screened; 53 were included in meta-analyses. HRT uptake was 53% lower in Black (OR 0.47, 0.30-0.73) compared to White women. Diabetes, obesity, and history of stroke or venous thromboembolism were associated with lower HRT uptake; (OR 0.71, 0.59-0.85; 0.67, 0.56-0.81; 0.75, 0.63-0.89; 0.78, 0.74-0.0.83 respectively). Osteoporosis and depression were associated with higher HRT uptake; (OR 1.64, 1.10-2.45 and 1.69, 1.17-2.43 respectively).
Conclusions: There are differences in HRT uptake by ethnicity and health characteristics. However, findings are not generalisable globally. Our results could aid healthcare professionals and policymakers to address the gaps in HRT uptake and promote healthcare equity
Deeper sociological insight needed for behaviour change: A systematic review of Chinese ivory consumption
Get PDFChinese consumer demand for ivory threatens vulnerable African elephant populations, despite long‐standing efforts to combat the illegal wildlife trade. Behavioural science approaches have been proposed to address these systemic behaviours. However, their robust use remains uncommon in demand management interventions. A culturally nuanced, psychological and sociological understanding of the behaviours driving ivory consumption is essential for effective behaviour change. We conducted a qualitative systematic literature review in English and Chinese to understand the drivers and barriers of Chinese ivory consumption. We sought to understand ivory acquisition, possession and disposal behaviours through purchase, gifting and inheritance practices. Our final review included 13 articles from the academic and grey literature. After inductive thematic analysis, we deductively applied UNICEF's Behavioural Drivers Model to support practitioner applications. Building on the limitations highlighted, we additionally deductively explored ivory consumption through a Consumer Culture Theory lens to assess ivory subcultures and market identities. Ivory consumption is driven by a mix of social, cultural and economic factors, and the degree to which each influences consumption behaviour is not well understood. Better understanding of Chinese social norms that affect individual and collective gifting behaviours could lead to more effective strategies to change behaviour. Most research focuses on purchase and does not address the underlying motivations for gifting and personal collecting to an extent that establishes actionable insight for behavioural interventions. Moreover, inheritance and bequeathing of ivory are not explored in the literature. This limits our understanding of the importance of familial and sentimental values and evolving generational values of ivory for consumers. Effecting demand for wildlife products requires diverse interventions aimed at different consumer groups to target different underlying motivations that shape consumer behaviour. If behaviour change interventions do not integrate evidence‐based behavioural insights into their design, it is unlikely they will successfully achieve their aims. Understanding social and cultural determinants of different consumer groups' behaviour is a critical component of designing effective behaviour change interventions for conservation outcomes. Read the free Plain Language Summary for this article on the Journal blog
Transitions in Chinese higher education: the case of St. John’s University, Shanghai
Get PDFThis dissertation use s St. John’s University, Shanghai, as a case study to explore developments in the Chinese higher education system from the late 1800s to the 1950s . St. John’s University was founded in 1879 and a study of its historical record offers a useful template against which to ex amine the historical transition of the Chinese higher education system. T he history of St. John’s was divided into three periods each would reflect crucial social changes in China : 1879 to 1911, 1911 to 1946, and 1946 to 1952. What if e ach period is marked by distinct social and cultural determinants , and Nationalism spurs them all and is seen as a critical f actor in igniting the formation of the Chinese higher education system In this, students play a crucial role. The dissertation , ex amines Chinese student movements during the republican period and the early PRC. It shows how t he social and cultural environment significantly affect ed the consequences of student movements
HLA-I, Natural Killer Cells and T Lymphocytes in Paediatric HIV Functional Cure
Get PDFAchieving a functional cure for HIV-1 remains one of the greatest challenges in medicine. Post-treatment control (PTC), where individuals sustain virological suppression after discontinuing antiretroviral therapy (ART), represents a particularly promising strategy. Infants appear to have enhanced PTC potential due to early ART initiation, immune tolerance, and the infection of less fit viruses compared to adults, making this group particularly informative for studying mechanisms of PTC. This thesis investigates the immunogenetic and immunological determinants of PTC in early ART-treated children living with HIV, to inform cure-directed interventions and identify paediatric candidates for analytical treatment interruption (ATI) trials. Chapter 3 reveals that children carrying low-expression HLA-A alleles exhibit reduced HIV-1 DNA levels, suggesting smaller reservoirs and enhanced cure potential, which were linked with NK cell phenotype and function. In contrast, females with protective HLA-B alleles displayed larger reservoirs associated with Th17-skewed immune profiles and therefore reduced cure potential. Chapter 4 demonstrates the potential for HIV-1 to alter population-level HLA-I frequencies in KwaZulu-Natal and that the introduction of ART has halted this selective pressure. Additionally, infants born in the ART era were shown to have reduced frequencies of high-expression HLA-A alleles compared to the pre-ART era, favouring PTC. Chapter 5 explores immunological differences between HLA-B*58:01 and HLA-B*58:02. HLA-B*58:01 was linked to heightened immune activation relative to HLA-B*58:02 in both healthy adults and early-ART treated children, suggesting that, despite its ‘protective’ classification in ART-naïve settings, HLA-B*58:01 may be less compatible with functional cure in early ART-treated children compared to HLA-B*58:02. Together, these findings highlight factors that enhance paediatric functional cure, including low HLA-A expression, heightened NK cell functionality, ‘disease-susceptible’ HLA-B alleles, and high ART coverage. This work helps advance our understanding of factors that enhance paediatric HIV-1 functional cure and supports the long-term vision of relieving children of lifelong ART
Seasonal forecasting using the GenCast probabilistic machine learning model
No full textMachine-learnt weather prediction (MLWP) models are now well established as being competitive with conventional numerical weather prediction (NWP) models in the medium range. However, there is still much uncertainty as to how this performance extends to longer timescales, where interactions with slower components of the earth system become important. We take GenCast, a state-of-the-art probabilistic MLWP model, and apply it to the task of seasonal forecasting with prescribed sea surface temperature (SST), by providing anomalies persisted over climatology (GenCast-Persisted) or forcing with observed SSTs (GenCastForced). The forecasts are compared to the European Centre for Medium-Range Weather Forecasts seasonal forecasting system, SEAS5. Our results indicate that, despite being trained at short timescales, GenCast-Persisted produces much of the correct precipitation patterns in response to El Ni˜no and La Ni˜na events, with several erroneous patterns in GenCast-Persisted corrected with GenCast-Forced. The uncertainty in precipitation response, as represented by the ensemble, compares favourably to SEAS5. Whilst SEAS5 achieves superior skill in the tropics for 2-metre temperature and mean sea level pressure (MSLP), GenCast-Persisted achieves higher skill in some areas in higher latitudes, including mountainous areas, with notable improvements for MSLP in particular; this is reflected in a slightly higher correlation with the observed NAO index. Reliability diagrams indicate that GenCast-Persisted has little skill relative to climatology, whilst GenCast-Forced produces forecasts with reliability comparable to SEAS5. These results provide an indication of the potential of MLWP models similar to GenCast for the ‘full’ seasonal forecasting problem, where the atmospheric model is coupled to ocean, land and cryosphere models
For the sake of simplicity
Get PDFThis article explores a neglected aspect of the doctrine of divine simplicity (DDS). Traditionally, DDS holds that God’s attributes, such as omnipotence and omniscience, are identical to each other and to God’s existence. While most existing literature explores the implication of DDS on other divine attributes, this article offers a systematic reflection on the property of being simple under the framework of divine simplicity. Addressing the ontological nature of simplicity itself raises novel and significant questions about the nature of God and the coherence of DDS. Through an examination of the property of being simple with respect to various ontological frameworks, particularly two versions of bundle theory, this article reveals that the attribute of being simple possesses a distinct ontological status, differing fundamentally from other divine attributes
Writing the History of Neoliberalism: A Comment
Get PDFThis series of comments brings together four historians of neoliberalism, each of whom focuses on a different part of the world but whose work has implications that are transnational if not global. Quinn Slobodian reconstructs the rise of the category of neoliberalism among historians and identifies the different paths of inquiry it is generating. Priya Lal, offering an Africanist’s perspective, moves beyond the reduction of the neoliberal narrative of the continent to one of linear declension and abjection by way of structural adjustment to show continuities from the colonial era to early independence. Gary Gerstle, an Americanist by training, offers a macro take on the move from a Keynesian and social democratic order to a neoliberal one while insisting we attend to the diverse ways policies and elite neoliberal ideas are taken up by populations for whom promises of freedom may mean something different from what intellectuals intended. Finally, Tehila Sasson, a historian of modern Britain and the world, explores the left-wing features of what has come to be called neoliberalism, insisting we keep a keen eye out for unintended consequences and unlikely origins. Together, the comment offers a satellite’s eye view of a subfield reaching maturity
Time frames: crisis expertise and rapid response mechanisms
Get PDFExperts step into global governance most prominently in times of crisis. But if crisis governance at international organizations (IOs) involves the construction of specific temporal horizons, how do these horizons affect the constitution of expert authority? This article argues that expertise produced under such conditions—to meet a demand for “timely” knowledge—differs substantively from other kinds of expertise. Crisis governance thus contributes in notable ways to the pluralisation of expertise. The article examines this phenomenon in the case of the relatively recent proliferation of rapid response mechanisms (RRMs). By examining the making and implementation of RRMs at two major IOs—the World Health Organisation and the World Food Programme—the article offers a new understanding how RRMs have become part of institutional repertoires of expertise. Based on this, it contends that RRM-based timeliness claims shift expert knowledge production from credentialed individuals to infrastructures and standardised procedures; second, they prioritise large homogenous datasets over consultation and contestation among different experts; and third, they streamline expert selection such that experts are recruited from existing intra-institutional pools rather than third parties. Jointly, these shifts speed up monitoring and reaction capabilities, but also risk eroding important checks on expert overconfidence