VictorJuiz/thesis huggingface dataset:
Regularity theory in the calculus of variations and elliptic systems

In this thesis we will investigate the regularity of critical points and minimisers of integral functionals of the form
F(w)=F(x,w,∇w)dx,
where the mappings w we consider will be vector-valued. This will be done from several different perspectives, with the goal of understanding when solutions are locally regular (of class C^{1,α} ) near a given point x0∈Ω
. This is typically done through a so-called “ε-regularity result,” which characterises the points x_0 which are regular in the above sense, by a smallness condition for a suitable excess quantity. We will investigate in three different aspects such regularity issues.
In the first part, we will consider the regularity for critical points of functionals satisfying a Legendre-Hadamard ellipticity condition. It is known by the works of Müller & Šverák [MŠ03] that critical points may be highly irregular (in particular nowhere C^1 ), however we show that regularity does hold if we assume an a-priori smallness condition of the gradient in BMO . Results will be obtained up to the boundary, and global consequences will also be explored.
In the second part, we will consider the existence and partial regularity theory for minimisers of non-autonomous quasiconvex integrands, subject to a general growth condition. By this we mean the growth of the integrand F is governed by an N -function, which we assume satisfies a ∆ 2 -condition. We will obtain a general existence theorem which will involve selecting a regularised minimising sequence along which we establish lower-semicontinuity, along with a partial regularity result. For the regularity theory we will additionally assume a non-degeneracy condition from below in the form of a ∇ 2 -condition, and we will discuss how this can be partially relaxed.
Finally in the third part, which is joint work with Lukas Koch (MPI Leipzig), we will consider relaxed minimisers for convex integrands satisfying a (p, q)-growth condition of the form
|z|p≲F(x,z)≲1+|z|q.
We will establish interior improved differentiability results in the Besov scales B
s,p
∞
, by means of a novel second order difference quotient technique. By using known ε-regularity results for minimisers in this setting, we obtain improved dimension estimates for the singular set.

Keywords: quasiconvexity
elliptic PDEs
general growth
calculus of variations
Advisor: Kristensen, J
Rupflin, M
Understanding the free energy landscapes and self-limiting assembly of DNA origamis using coarse-grained modelling

Coarse-grained modelling of DNA nanostructures allows their structural, mechanical and thermodynamic properties to be characterised. In this thesis, we illustrated how coarse-grained modelling combined with umbrella sampling can be applied to compute the free energy landscapes of large DNA nanostructures, and how these landscapes can be used to characterise the self-limiting assembly of DNA origamis.
We first described the mechanical deformation of DNA nanotubes by computing their free energy landscapes using distance-based order parameters. We analysed the behaviour of the nanotubes under different levels of bending stress and compared their behaviour to the worm-like chain model, revealing two regimes of bending depending on the localisation of the bending stress. We further demonstrated the computation of free energy landscapes on a mechanically bistable DNA origami. Interestingly, the landscape computed from simulations only shows one minimum, which is different from the bistable landscape inferred from experimental observations of ensembles of origamis. We decomposed the landscape into one component for each joint in the origami and discovered that only one such component showed bistability, which was masked by the other components and resulted in an overall landscape with a single minimum.
We also examined the self-limiting assembly of DNA origamis. We studied a DNA origami that assembles with stress propagation through displacement accumulation. We characterised the structural properties of the origami monomer and its polymers, as well as the free energy landscapes of the monomer associated with the main stress accumulation mechanisms. We parameterised a simple one-dimensional model using the landscapes and ran Monte Carlo simulations to estimate the stress free energy of polymers as a function of their lengths. As an extension, we explored other possible DNA origami designs that could undergo self-limiting assembly through mechanisms other than displacement accumulation. In particular, we evaluated the use of curvature and twist accumulation to propagate stress in assemblies of DNA origamis.

Advisor: Doye, J
A narrative review of caregiver training programmes aimed to improve child language development in low-resource African communities

Most children in Southern and Eastern Africa are not reaching their language and literacy milestones at expected rates, hindering future development from a personal and economic perspective (UNESCO, 2019). Children learn through their interactions with their caregivers. There is potential for caregivers to positively impact their child’s development, through their daily interactions and caregiving practices. The aim of this study was to determine what caregiver training programmes have empirical evidence regarding their level of effectiveness on child language and literacy outcomes and what is the quality of these programmes. The study is a narrative review of eligible caregiver training programmes from Southern and East African contexts, which aim to improve child language or literacy outcomes. A total of 905 studies were initially found from database and grey literature searches. A total of nine studies were screened to be eligible for inclusion in this review. The results of the study showed that there are effective caregiver training programmes in Southern and East Africa which show short term effects on child language or literacy outcomes, but the results show that the research studies fail to assess the medium to long term impact of the caregiver training programmes on child language or literacy outcomes. The results show that eligible training programmes do not align with all the optimal components of design and implementation, which implies that there is potential for caregiver training programmes to improve by increasing intensity, improving supervision, utilizing effective teaching strategies, and ensuring deep structural sensitivity of the programme is achieved.

Keywords: preschool
language development,
child development
reading
parent
learning
Management of dengue shock syndrome: evaluating fluid resuscitation strategies and novel monitoring systems to improve outcomes


Dengue is the most significant mosquito-borne viral infection in humans. Dengue shock syndrome (DSS) is one of the dengue complications and can be fatal if not recognized and treated promptly. The management of DSS relies mainly on judicious fluid replacement and frequent haemodynamic assessments. Optimal fluid therapy is yet to be defined due to limited evidence. Current methods for monitoring patients with DSS are also unreliable and less sensitive. My thesis aimed to review different fluid resuscitation strategies currently used for paediatric DSS across dengue-endemic countries in Asia, and assess the clinical utility of several novel non-invasive monitoring devices in children with DSS.
First, I performed a systematic review of randomised controlled trials on fluid resuscitation for children with DSS or septic shock. I collected retrospective data on fluid management in 7 hospitals in Asia anonymously and compared the outcomes of different fluid strategies. Second, I used prospective data from 103 severe dengue patients admitted to ICU and investigated the ability of the Compensatory Reserve Index (CRI) to predict recurrent shock (reshock). Finally, I conducted a prospective observational study on 92 children with DSS to describe the fluid response and trajectories of intravascular volume changes during fluid resuscitation using point of care ultrasound and a bioimpedance device (NICaS).
I demonstrated the high heterogeneity of published studies on fluid resuscitation in children could not provide strong recommendations on fluid types and fluid rates for both DSS and septic shock. There was a wide variation of fluid management for DSS across the Asian regions. The use of colloid or crystalloid in the first 2-hour of resuscitation provided similar outcomes; the prolonged use of synthetic colloids for more than 4 hours reduced the reshock occurrence but increased significantly respiratory compromise. I have demonstrated the utility of CRI in predicting reshock, as well as showing the reliability of continuous measurements derived from NICaS in intravascular volume monitoring compared to echocardiography.
Overall, my work has added to the overall body of evidence of fluid management for DSS patients and the utility of different monitoring tools. This may help pave the way for personalised fluid trials for DSS management in the future.

Keywords: bio-impedance
fluid resuscitation
compensatory reserve index
shock
echocardiography
non-invasive monitoring
reshock
dengue
pulse waveform
Advisor: Bridget, W
Sophie, Y
Lam, P
Intentionality and mental events

Of the many groups of problems falling under the genral heading "intentionality" three will be discussed in this thesis - firstly, that nest of problems surrounding the various criteria for intentional sentences, and with the thesis that interntionality is the mark of psychological sentences; secondly, those views and queries surrounding the notion of an intentional object, and particularly the problems concerning the nature and definition of such objects; and thirdly the more traditional area, viz. problems concerning the account which is to be given of the relation between a mental event or activity and its object.
Continued in thesis ...

Keywords: mental events
philosophy
intentionality
object
Advisor: Gosling, JCB
Monetary policy, financial stability, and default in advanced and emerging marketing economies

This thesis consists of three self-contained essays on monetary policy, financial stability, and default risk, which are applied in the context of Advanced Economies (AEs) and Emerging Market Economies (EMEs). Chapter 1 explores whether concerns for financial stability are a justification for Euro Area monetary policy to lift off the zero lower bound (ZLB) on nominal interest rates. Through the lens of an optimizing central bank, I study the consequences of a departure from the ZLB in a general equilibrium model with banks, collateral constraints, and default. Debt-deflationary forces of default sharpen the policy trade-off to central banks as they erode bank profitability and depress aggregate demand. My results thus support the argument that central banks ought to internalize the externality of their monetary policy decision on financial stability. Chapter 2 investigates the role of financial stability for monetary policy in EMEs, which are notoriously vulnerable to external shocks. Using the Mexican economy as a laboratory, I build a small open economy DSGE model with banks and firm default. I study whether a “leaning against the wind” policy can mitigate the effects of an external funding shock to the banking sector. I find that an interest rate rule augmented by a measure of expected default risk and the regulatory cost of bank capital outperforms conventional interest rate rules. This is because monetary policy takes into account financial amplification of firm default via banks’ balance sheets, which firms do not internalize. Chapter 3 uncovers whether credit risks that emanate from the corporate sector in EMEs can causally explain international capital flows. Using granular data on the universe of corporate bonds issued by non-financial firms in a large set of EMEs, I extract idiosyncratic shocks to large corporate borrowers. These shocks allow me to construct “Granular Instrumental Variables” (GIV) to identify this causal relationship. I show that corporate credit risk acts as a powerful amplifier of business cycle fluctuations in EMEs above and beyond global and sovereign risk. This thesis thus provides a novel policy implication: the interaction of private default and liquidity frictions can create important pecuniary externalities that, beyond the use of prudential regulatory measures, ought to be taken into account by monetary policy makers.

Keywords: financial stability
corporate credit risk
capital flows
emerging market economies
default
monetary policy trade-off
zero lower bound
Advisor: Tsomocos, D
Wilson, M
Investigating the effects of cGAS-STING-dependent innate immune responses in BRCA2-deficient cells


Tumours with BRCA2 gene deficiency, retain the ability to proliferate, despite the genomic instability resulting from DNA damage accumulation. These tumours can be targeted with Poly-ADP ribose polymerase inhibitors (PARPi), which increase the susceptibility of BRCA2-mutated tumours to DNA damaging agents. However, in spite of the therapeutic benefits and low toxicity in patients, PARPi resistance remains a clinical challenge. Therefore, improved approaches for targeting BRCA2-mutated tumours are being sought to improve patient outcomes. Previously, BRCA2 depletion was shown to activate the cGAS-STING-dependent innate immune responses which have the potential to promote antitumour immunity. In this project, we set out to investigate the effects of stimulating the cGAS-STING-dependent innate immune responses using the STING agonist DMXAA in two BRCA2-deficient cell models. DMXAA treatment activated the cGAS-STING signalling pathway in only one of the BRCA2-deficient cell models, characterised by an increase in IRF3 phosphorylation, but this did not lead to an increase in DNA damage. PARPi treatment is known to activate the cGAS-STING signalling pathway and induce DNA damage in BRCA2-deficient cells. Therefore, we co-treated BRCA2-deficient cells with the PARPi Talazoparib and DMXAA in order to activate STING mediated innate immune responses and increase DNA damage. The combination treatment led to activation of cGAS-STING signalling, upregulation of interferon-stimulated genes and an increase in DNA damage in both cell models. Finally, we investigated the effect of combining DMXXA and Talazoparib on the viability of BRCA2-deficient cells. However, DMXAA did not lead to increased sensitivity of the BRCA2-deficient cells to Talazoparib. Whilst these are preliminary results, they suggest that the effect of STING agonists may vary depending on cell type and they may not have the predicted efficacy in BRCA2-deficient cells.

Keywords: STING agonists
PARPi
Genomic Instability
Cancer
Talazoparib
BRCA2
DMXAA
Advisor: Tarsounas, M
Understanding the experiences and needs of parents with psychosis and those of their families

The aim of this thesis is to improve understanding of the experiences and needs of parents with psychosis and those of their families. Chapter 1 describes the current literature and establishes that research to date has largely focused on parents with affective disorders, without much attention given explicitly to parents with psychosis.
Using anonymised patient records in secondary care, Chapter 2 shows that over a third of patients with psychosis are parents but many dependants are not accurately recorded in patients’ clinical notes. A binomial regression indicated that parenthood was associated with being female, older, and having ever been married. A survival analysis found that smoking, being single and a diagnosis indicating affective symptoms were all associated with relapse in parents with psychosis.
Chapter 3 uses qualitative methods to investigate families’ needs in more depth. Some of the themes generated in these analyses highlight difficulties in communicating about psychosis, parents’ need to protect their children, and the bidirectional relationship between stress from parenting and psychotic symptoms. Chapter 4 investigates this relationship between parenting stress and psychosis using intensive longitudinal sampling. Multi-level modelling showed a significant relationship between parenting stress and psychosis in both directions, with negative affect identified as an important mediator.
Chapter 5 investigates needs from a service-level perspective using focus groups with mental health professionals. These professionals highlighted how the needs of parents with psychosis depend on symptom severity and the availability of social support. Chapter 6 uses two systematic reviews to establish what interventions are available for parents with psychosis and their families. The results of these reviews suggest that no intervention has been tailored specifically to meet the needs of parents with psychosis, but that there is a growing evidence-base of interventions for parents with mental illness that may benefit parents with psychosis.
Chapter 7 summarises the needs and experiences of parents with psychosis and their families. It highlights that their needs are complex and dependent on many factors, including symptom severity, gender, and the family’s wider environment. It concludes by discussing interventions and supports that could address these needs.

Keywords: quantitative
qualitative
experience sampling methodology
psychosis
parenting
parental mental illness
Advisor: Johns, L
Barlow, J
Articulations: settler colonialism, dispossession and arts in post-Oslo Palestine

This research project explores the relationship between Palestinian cultural production, urban expansion/renewal, settler colonialism, and late capitalism in the post-Oslo historical conjuncture in Israel/Palestine. Using in-depth interviews with Palestinian artists, archival materials and audio-visual materials, the project traces the journeys of Palestinian artists as they navigate the socio-spatial processes reproducing the urban fabrics of two cities: Haifa in the north of historic Palestine (today’s Israel) and Ramallah in central West Bank. I look at the Palestinian village of ‘Ayn Hawd in Haifa and its transformation into the arts settler colony of Ein Hod in 1953; the layered history of dispossession, first of the Palestinian in 1948, then of the Arab Jew in 1959 in Wadi Salib; and the contemporary urban expansion and renewal, respectively, of the Ramallah and Haifa and their associated forms of cultural production.
The project makes two overarching arguments. First, I argue that the dispossession of the Palestinian and the racialization of the Arab Jew serve as the inherited background within which modes of urban production across Israel/Palestine unfold. In the second vein, I read the urban transformations in the two cities since the early 1990s as reflective of the increasingly central role the market has come to play following the neoliberalisation of the Israeli economy in 1985 and the Oslo Agreement in 1993 and their concomitant fashioning of consumerist subjects across the ‘Green Line.’ In this context of dispossession, I posit that Palestinian arts and cultural boycotts connote ‘practices of articulation’ that mean (via Antonio Gramsci and Stuart Hall) neither total incorporation into, nor a total reclaiming of the settler colonial spatialization of the city. Rather, I argue that they are part of a necessarily unequal struggle towards opening up cultural possibilities.
The project contributes to two overarching debates: the first pertains to human geography and focuses on the relationship between dispossession, urbanization and arts within city-forms. It argues that urbanization—understood as capitalist agglomeration—has to be understood as one among many historically specific and socially embedded socio-spatial processes. The second contribution pertains to both urban studies and cultural studies. By examining modes of cultural production as nonlinearly mediated through economic, political, urban and juridical spheres, I show how arts are socially constituted and so are the subjectivities of the artists that produce them.

Keywords: Haifa
Israel/Palestine
dispossession
Ramallah
Ein Hod
arts
cities
settler colonialism
Advisor: Daley, P
Vasudevan, A
Characterisation of astrocyte diversity in the multiple sclerosis motor cortex

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system where neurodegeneration often leads to irreversible disability. Clinical and pathological heterogeneity is the rule, with genetic (e.g. HLA-DRB1*15 status) and environmental factors playing important roles. The mechanisms underlying such heterogeneity remain elusive. Astrocytes, which are involved in MS pathogenesis, are an attractive candidate to contribute to such variation in MS pathology due to their complex functions in health and disease. Recent progress has also challenged the conventional view that astrocytes represent a homogenous population, indicating that astroglial diversity may underscore MS heterogeneity.
In this thesis, we undertake a quantitative neuropathological analysis of GFAP+ and ALDH1L1+ astrocyte subpopulations in the motor cortex of a large cohort of human post-mortem MS cases genotyped at the HLA-DRB1*15 locus. We find that GFAP+ and ALDH1L1+ astrocytes represent distinct subpopulations that differ in their distribution along the motor cortex and in their relationships with MS pathological outcomes. GFAP+ astrocytes show a greater extent of reactivity in the MS motor cortex, especially in areas of demyelination and in younger HLA- DRB1*15+ cases. In contrast, MS ALDH1L1+ astrocytes associate with neuronal density and macrophage/microglial inflammation, a relationship not seen in cases carrying the HLA-DRB1*15 allele. These astrocyte subpopulations also vary in their relationship with surrogate markers of blood-brain barrier dysfunction with decreasing perivascular GFAP+ astrocyte expression and increasing perivascular ALDH1L1+ astrocyte expression in MS. Given the histopathological differences between the two astrocyte markers, we also perform proteomics using laser capture microdissection coupled to mass spectrometry to probe the deep proteome of GFAP+ and ALDH1L1+ astrocyte subpopulations. Protein expressions show clear differences between GFAP+ and ALDH1L1+ astrocytes. In MS cases, GFAP+ astrocytes abundantly express immune-related proteins compared to ALDH1L1+ astrocytes, which associate with protein expression changes related to synaptic vesicle clustering and voltage-gated potassium channels. Immune-related proteins in astrocyte subpopulations are impacted by the carriage of the HLA-DRB1*15 allele.
Altogether, our data implicate astrocyte subpopulation diversity as a contributing factor of MS heterogeneity. We suggest that GFAP+ astrocytes have relatively detrimental roles, whilst ALDH1L1+ astrocytes have relatively protective roles in MS. This thesis highlights the pressing need to understand the role of astrocyte diversity in MS so that selective targets amenable to therapeutic modulation may be identified and halt the devastating outcomes of MS.

Advisor: De luca, G