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The identity development of high-ability students in mainland China
No full textGifted education has become an increasingly important area of study worldwide. However, research on how high-ability students perceive their abilities and construct their identities, particularly in non-Western contexts, remains limited. In China, the concept of giftedness is often shaped by strict academic standards and cultural expectations, which can influence how students understand and navigate their abilities. Since the terms gifted is seldom used in China school settings, I have adopted the term high ability instead. This study aimed to explore the identity development of perceived high-ability Chinese high school students within two contrasting school types: a key school where students may display relatively high general intelligence and a regular school where students may exhibit high ability in specific subjects but not across all domains.
A qualitative study was conducted to achieve the research aim. The sample included 18 students from two different types of schools, nominated by teachers as high ability, along with 17 mothers and 8 class teachers, all from a province in mainland China. Data were collected through semi-structured interviews with students, teachers, and guardians, supplemented by ten diaries from students at the key high school to deepen the exploration of students’ experiences. Due to the demanding study schedules in the regular school and the administrators’ directive to minimise time spent on research activities, no diaries were collected from the regular high school students. NVivo software was employed for data management and analysis. All data were analysed using thematic analysis.
Three main themes emerged from the data: (1) School and Self - High school students tended to form identities centred around numerical achievements and often downplayed their abilities. The competitive environment of the school heightened pressure to meet the education system’s high standards, creating a tension between prioritising achievements and nurturing personal relationships. (2) Family and Self - The complexity of family involvement and expectations contributed to high-ability students’ views on their abilities and future plans. (3) Culture and Self - Cultural influences on perceptions of high ability. Chinese cultural norms surrounding high ability set narrow criteria for its evaluation and emphasised humility and efforts, which could lead students to undervalue their own abilities. This research suggests that sociocultural, systemic, and institutional factors form a complex interplay in shaping the identities and experiences of high ability students in mainland China. It also highlights the need for more inclusive and supportive educational practices that recognise and nurture the diverse potential of high ability learners in the Chinese context
Reducing unprocessed red and processed meat consumption in Mexico for environmental and health benefits
No full textBACKGROUND:
Meat consumption trends in Mexico are poorly understood. To fill this gap, I assessed trends in protein-rich food groups including meat, and the contribution of unprocessed red and processed meat to nutrient intake.
METHODS:
I used nationally representative (all ages) dietary information from ENSANUT, collected using a semi-quantitative food frequency questionnaire in 2006 (n = 38,775), 2012 (n = 6,729), 2016 (n = 14,537), 2018 (n=23,516), and 2020 (n= 2,033). I tested for time trends and sociodemographic differences in daily consumption using survey-weighted generalised linear regression, adjusting for total energy intake. The contribution to nutrient intake was assessed from a 2016 24-hour dietary recall (n =4,070).
RESULTS:
Energy-adjusted unprocessed red meat consumption decreased slightly from 2006 to 2020, but processed meat remained unchanged [change in daily consumption (g) per survey-cycle (95% CI)]: β = -0.28(-0.49, -0.08) and 0.01(-0.06, 0.09), respectively]. Among 6–19-year-olds, unprocessed red and processed meat consumption increased (P-trend <0.001). Other protein-rich foods such as seafood [-0.12 (-018, -0.07)], and legumes, nuts and seeds [-0.85 (-1.11, -0.60)] decreased over time, while poultry [0.52(0.38, 0.66)] and dairy [1.09 (0.08, 2.11)] increased. Egg consumption remained constant [0.01 (-0.10. 0.12)]. Unprocessed red and processed meat contributed substantially to per capita haem iron intake (23% and 26%, respectively) and vitamin B12 intake (17% and 9.8%, respectively).
CONCLUSION:
Processed meat consumption has not declined in Mexico and is increasing among young people, with potentially negative health and environmental consequences. Meat was an important contributor to haem iron and vitamin B12 but less important (<10%) for all other essential nutrients, therefore policies to encourage meat reduction, particularly processed meat, are unlikely to have an adverse effect on nutritional status
Dissecting tumor cell heterogeneity and tumor-microenvironment interactions in bone metastatic prostate cancer using single-cell and spatial transcriptomics
No full textProstate cancer is the most prevalent form of cancer among men in western societies. The treatment of prostate cancer has advanced over recent decades, built upon the cornerstone concept of androgen deprivation. The fundamental principle is to reduce the responsiveness of prostate cancer cells to androgens, thereby limiting tumor growth. However, castration-resistant prostate cancer (CRPC) is widely observed in both primary and metastatic prostate cancer. At this stage, prostate cancer cells no longer respond to androgen deprivation therapy (ADT), marking the most severe phase of the disease. This advanced stage is responsible for over 90% of deaths.
In this study, a novel in vivo model was employed to mimic the development of resistance to ADT in bone metastatic prostate cancer. Using single-cell and spatial transcriptomic techniques, transcriptomic data were collected from bone metastatic samples at sequential ADT time points from ADT sensitive to resistant stage. The heterogeneity of cancer cells was investigated, and surprisingly, a subpopulation at the resistant stage was identified in both mouse and human datasets. Then, cell types within the tumor microenvironment, such as immune and mesenchymal cells, were analysed to explore their heterogeneity during tumor progression. Finally, the single-cell data with identified cell types from the previous steps were used to deconvolute the cell types in the corresponding spatial transcriptomic data from the same model. In the exploration of spatial organization, a co-occurrence between resistant tumor cells and infiltrated tumor-associated macrophages (TAMs) was observed. Through integrated analysis of the data, cellular heterogeneity and spatial landscape in bone metastatic prostate cancer were investigated, offering insights into tumor progression and microenvironmental interactions
Functional mechanisms, conservation, and origin of the immunoglobulin M and alpha-2 macroglobulin binding phenotypes of Plasmodium falciparum
No full textPlasmodium falciparum is responsible for hundreds of thousands of mortalities among children
and infants each year. These deaths are largely due to severe childhood malaria and
pregnancy-associated malaria. The unique virulence of this malaria parasite is defined by
the expression of multivariant surface antigens known as P. falciparum erythrocyte membrane
protein 1 (PfEMP1) on the surface of infected erythrocytes. PfEMP1 antigens facilitate
the adhesion of the infected erythrocytes in various organs including the brain and placenta,
thereby resulting in organ dysfunction and lethal outcomes of infection. Therefore,
PfEMP1-mediated adhesion phenotypes represent an important area of study. Among
these phenotypes, the binding of infected erythrocytes to the serum protein immunoglobulin
M (IgM)-Fc is the only phenotype associated with all forms of life-threatening malaria.
The binding to another serum protein, α₂-macroglobulin (α₂M), has also been linked to severe
childhood malaria. Consequently, there is need to investigate the PfEMP1 proteins
involved in these phenotypes by characterising the binding mechanisms and conservation.
In this thesis, I aim to establish the functional mechanisms, conservation, and origin
of the P. falciparum IgM-Fc and α₂M binding phenotypes with a goal of determining if the
corresponding antigens can be targeted for vaccine development.
First, I investigated the functional mechanisms of IgM-Fc and α2M binding in P. falciparum.
I have characterised the IgM-Fc/α2M binding domain of a newly identified domain
cassette 11 (DC11) subtype PfEMP1 variant (DC11 11019VAR1). I expressed the DC11
11019VAR1 domains in Escherichia coli and used enzyme-linked immunosorbent assay
(ELISA) to show that the duffy-binding like (DBL) ζ3 domain binds both IgM-Fc and α2M.
This is important as DBLζ3 has been linked to severe malaria, but the phenotype was
unknown. I have also investigated α2M binding in various IgM-Fc binding/non-binding
PfEMP1 domains using ELISA and characterised the potential minimum binding region
involved in α₂M binding. I report that α₂M binding is mediated by DBLζ2/3 domains and
that the interaction potentially involves the full-length DBLζ2 domain. In addition, I have
profiled the PfEMP1 variants potentially involved in rosetting IgM-Fc binding from newly
adapted P. falciparum clinical isolates. I have identified novel rosetting-associated domains
(DBLα0.11 and DBLα0.5).
Secondly, I have examined the conservation of the IgM-Fc and α₂M binding phenotypes
in the global P. falciparum population using publicly available PfEMP1 databases (Pf3k
varDB). I have used a novel approach that combines sequence variation and antibody
cross-reactivity data to predict a clinically relevant threshold for conservation of PfEMP1
domains. By using basic local alignment search tool (BLAST), I report that at the threshold
of ≥80% amino acid identity, the IgM-Fc binding IT4VAR2CSA DBLεpam5 (found in 9 out
of every 10 Pf3k Normalised varDB isolates) and IgM-Fc/α2M binding DC11 TM284VAR1
DBLζ2 (found in 4 out of every 10 Pf3k Normalised varDB isolates) are relatively conserved
in the global population. This greatly exceeds the sequence conservation of domains
involved in other adhesion phenotypes (found in 1 out of every 20 Pf3k Normalised varDB
isolates). My results suggest that the PfEMP1 IgM-Fc and IgM-Fc/α₂M binding domains
experience unusual selection pressure. This is likely due to the unique properties of the
IgM-Fc and IgM-Fc/α₂M binding DBLε/ζ domains which have undergone specialisation
and experience lower intra-clade recombination thus promoting sequence conservation.
Moreover, IgM-Fc binding masks the infected erythrocyte from IgG-mediated phagocytosis
and this functional role might favour positive selection.
Finally, I have investigated the evolutionary origins of the P. falciparum IgM-Fc and
α₂M binding phenotypes. I have analysed the conservation of the PfEMP1 IgM-Fc
and IgM-Fc/α₂M binding domains in the subgenus Laverania, the closest relatives of
P. falciparum. I used BLAST and phylogenetics to demonstrate that the gorilla parasite
P. praefalciparum has orthologues of IgM-Fc binding domains while the chimpanzee
parasite has orthologues of both IgM-Fc and IgM-Fc/α₂M binding domains. I have also
expressed the orthologues of the PfEMP1 IgM-Fc/α₂M binding DC11 TM284VAR1 DBLζ2
(PRG01_0043100 DBLζ2) and DC15 HB3VAR06 DBLζ2 (PPRFG01_00100700 DBLζ2
and PPRFG01_1100100 DBLζ2) in E. coli. I used ELISA to show that PRG01_0043100
DBLζ2 binds to human IgM while PPRFG01_00100700 DBLζ2 and PPRFG01_1100100
DBLζ2 bind to human IgM and α₂M in a concentration-dependent pattern. This shows that
the PfEMP1 IgM-Fc and IgM-Fc/α₂M binding phenotypes are ancient, greatly predating
the origin of P. falciparum.
In conclusion, I have identified a novel IgM-Fc/α₂M binding DC11 DBLζ3 domain that is associated
with severe malaria and report novel rosetting-associated domains. I also report
that the PfEMP1 IgM-Fc and IgM-Fc/α₂M binding domains are relatively conserved in the
global P. falciparum population and within the subgenus Laverania. The unique conservation
of these domains indicates that they might be experiencing functional constraints.
Therefore, the PfEMP1 IgM-Fc and IgM-Fc/α₂M binding domains could be potential vaccine
candidates to protect against severe childhood malaria and pregnancy-associated
malaria
Empowering antibiotics using host defence peptide to fight antimicrobial resistance in epithelial and systemic infections
No full textAntimicrobial host defence peptides (HDPs) show great promise in combating antimicrobial-resistant (AMR) bacteria. However, their use is limited by restricted activity in physiological conditions and cytotoxicity at functional concentrations. A class of synthetic antibacterial and anti-biofilm peptides (SAAPs) with enhanced activity against AMR pathogens has recently been developed to bypass these limitations, particularly in combination with other antibiotics. This project sought to assess the antibacterial activity of a leading candidate, SAAP-148 – and its synergism with antibiotics – across an array of representative in vitro and in vivo models of bacterial infection. Employing and augmenting the high-throughput in vitro model systems of three-dimensional (3D) human skin, lung, and bladder epithelial cultures, and the fruit fly (Drosophila melanogaster) as an in vivo model, respectively, I have: (1) reviewed and analysed the published literature on the combined use of HDPs and antibiotics against AMR bacteria; (2) established the efficacy of SAAP-148 against AMR bacteria in 3D models of infection, including its synergistic interactions with the novel nonpeptide antibiotic halicin; (3) clarified the preventative activity of SAAP-148 against AMR bacteria in skin tissue models, contrasted by its activity in lung tissue models; (4) identified the complementary interactions of SAAP-148 pre-treatment with post-infection halicin in skin and lung tissue models; and (5) developed a dual microinjection model of bacterial infection and antibiotic treatment in D. melanogaster for the assessment of novel therapeutics in vivo. These findings lend support for the use of SAAP-148 as a prophylactic treatment against AMR bacterial infections of the skin, its potential as a synergistic therapeutic in combination with halicin, and the translational utility of D. melanogaster as an in vivo model of both bacterial infection and antibacterial treatment with HDPs
Robotic dexterous manipulation of cables
No full textHumans use their hands to dexterously manipulate cables to perform various tasks, like grasping cables, moving cables in hand without dropping them, bending the cable into a U shape for hooking, USB-cable insertion and so on.
Unlike dexterous manipulation of rigid objects, dexterous cable manipulation skills are still underexplored in robotics due to the unique challenges posed by cables' deformability and uncertainty. Thus, we focused on using a multi-fingered hand to perform dexterous manipulation of cables.
To build a robotic system for dexterous cable manipulation, we first need a good perception of the cable.
During manipulation, the cable is often partially occluded by fingers.
Thus, our first work is to propose a robust cable perception pipeline in 3D against occlusions.
We followed three steps: first, extracting a 2D mask from an RGB image, getting several key points to describe the target cable from the segmented point cloud, and finally, applying physical smoothing to the key points to make the reconstructed cable physically realistic.
After establishing a good cable perception system, we focused on the multi-fingered hand, a new end-effector for cable manipulation.
While existing research has addressed cable manipulation with grippers, using a dexterous hand introduces specific difficulties in tasks such as cable grasping, sliding, in-hand bending, etc, for which no dedicated task definitions, benchmarks, or success metrics exist.
Our initial exploration was based on using a multi-fingered hand-in simulation to perform some basic cable manipulations.
Due to the difficulty of high-dimension control and limited hand motion data, we used Reinforcement Learning to train an agent based on an anthropomorphic hand with 20 degrees of freedom. We proposed five tasks, including in-hand cable sliding from left to right and from right to left, object lifting, cable end-tip position control, and cable bending.
We achieved relatively good results with over 60% success rate on these tasks.
However, implementing the system in the real world becomes an entirely different case, and three things are needed: 1. a benchmark for dexterous cable manipulation, 2. a better-designed multi-fingered hand for dexterous cable manipulation, and 3. a controller that can perform high-dimensional manipulation in the real world.
We provided three solutions:
(1) We first defined and concluded a series of dexterous cable manipulation tasks into a taxonomy covering most one-hand cable manipulation short-horizon primitives and long-horizon tasks.
This proposed taxonomy revealed that thumb-index composition is critical for cable manipulation and decomposed long-horizon tasks into shorter primitives.
(2) We designed a new five-fingered hand with 25 degrees of freedom.
It has two symmetric thumb-index compositions and a rotatable joint on each fingertip, which allows it to perform tasks that are even difficult for humans.
Besides, we created a demonstration data collection pipeline for this hand.
(3) We defined a finite state machine based on collected demonstrations of short-term primitives.
The hand can robustly replay 7 short-horizon primitives with over 90% success rate on cables of the same material and over 72% on cables of different materials. For long-horizon tasks which need combinations of at least three primitives, the hand can replay four long-horizon tasks with over 75% on cables of the same material
Weather shocks, conflict and effective, scalable interventions
Get PDF‘Lightning talk’ presented by Nathan Jensen (University of Edinburgh) at the Jameel Observatory Community of Practice meeting, Addis Ababa, 13-14 May 202
Co-creation of a research agenda for localized anticipatory action in Somalia
No full textThis report was commissioned by Save the Children as a contribution to the ‘Reducing Impacts of Disasters Using the Anticipatory Action Framework in Somalia’ project funded by the Government of Germany. It sets out a set of research agendas that aim to address anticipatory action challenges prioritized in several in-country workshops
Improving access to geospatial climate risk data
Get PDFPlanning authorities in Scotland are required to prepare evidence reports as part of the local development plan (LDP) process. These provide a summary of the baseline data used and explain the implications of the LDP. Accurate, sub-national spatial data, which identifies geographic features such as rivers and utilities, is vital to create effective plans with a sound evidence base to evaluate climate risks. Fully evidencing climate risk requires an understanding of hazards, but also exposure and vulnerability, typically requiring interpretation of multiple datasets at once. This report explores the geospatial resources that are available to support the evidence gathering stage with a view to improving access to geospatial data on climate risk. It identifies existing data, data gaps, barriers, and resources needed for evidence-based planning and delivery
The phonetics of emphasis in Central Mount Lebanon Lebanese: acoustics, perception, articulation
No full textThis thesis is a descriptive analysis of the phonetics of emphasis in the variety of Lebanese spoken in Central Mount Lebanon (CMLL). It is both empirically and methodologically motivated, and bases its discussions around acoustic, perceptual, and articulatory data, collected from native speakers for the purposes of this thesis. The background chapters frame the variety and the phenomenon in their contexts, the data chapters dive into the experimental studies that make up the methodological core of this project, and the discussion frames the results of the different experimental approaches in relation to one another.
The acoustic study uses production data from 11 participants, recorded in Central Mount Lebanon. It finds no purely consonantal correlate to emphasis, and no statistically significant evidence towards the widely-reported F2 lowering correlate of emphasis, at vowel midpoint, across all vocalic contexts. The vowel midpoint analysis (using linear mixed models) only shows significant lowering of F2 for schwa and for long low vowels, the latter of which I report in my 2019 MScR dissertation to be categorically split into front and back low vowels with emphasis having a backing effect on the front category (/æ, ɑ/ → [ɑ] / [+EMPH]). The dynamic analysis (using univariate generalised additive mixed models) only finds a statistically significant lowering of F2 in the pre-emphatic voiceless sibilant context (_ṣ) for the low vowel, while the F2 lowering shown in other phonological contexts cannot be shown to be significant with this data. An early version of this study was published in the Journal of Semitic Studies in 2023.
The perceptual study is based on a lexical decision task given to 60 native speakers in Central Mount Lebanon. They were asked to determine whether the recording they heard matched an image associated with the plain or the emphatic member of a minimal pair. The recordings consisted of each of the original words (eg. /sīn/ versus /ṣīn/), a cross-splice of an emphatic- adjacent vowel from the word with an emphatic into the word without (eg. the /ī/ from /ṣīn/ spliced into /s_n/), and a cross-splice of the vowel in the same position from the word without the emphatic into the word with (eg. the /ī/ from /sīn/ spliced into /ṣ_n/). Using logistic regression analysis, the study finds that listeners rely on the consonant to detect emphasis in most cases, but that they instead rely on the vowel before the voiceless sibilant, in unrounded vowels after the alveolar plosives, and in unrounded vowels before the voiced alveolar plosive. As an aside, the study also shows that the emphatic-plain contrast in voiced alveolar fricatives (/ẓ/ versus /z/), while phonemic, is lexically less prominent than other such contrasts in CMLL.
The articulatory study uses ultrasound tongue imaging (UTI) data, recorded from 5 speakers of Lebanese living in Edinburgh. It explores the use of multivariate generalised additive mixed models, then dives into kinematic analyses. The data used in the study consists of CVb nonce syllables, setting the target emphatics and their unemphatic counterparts in the onset, with a voiced bilabial in the coda. It finds that there is a difference between the articulation of emphatic consonants and plain consonants. The difference in articulation occurs at the level of the pharynx, at consonant offset. The data does however suggest that the difference in articulation— this back, second constriction— occurs either further forward in the oral tract towards the uvula or velum at consonant offset, or at the pharynx earlier back in time before consonant offset, if the immediately subsequent vowel is frontal.
The discussion, grounded in theories of co-articulation, brings together the results of the three experiments, with a view to interpreting how the phonological phenomenon of emphasis operates on a phonetic level, and how the findings of three complementary experimental phonetic approaches can inform our understanding of a complex phonological phenomenon
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