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Supervised Learning Algorithms to Extract Market Sentiment: An Application using Commercial Real Estate Market
No full textSentiment analysis has become a key area of research in economics and finance with methods evolving from traditional survey-based analysis to computational linguistic techniques. New developments in data handling and analysis have allowed extracting sentiment from vast amounts of written documents. However, these methods depend heavily on the existence of training and test data sets. The choice of training data is critical in such applications. We show a novel application from a unique market – commercial real estate. There are several unique attributes of the real estate market that makes such analysis critical for insightful market intelligence. In the absence of training data sets for the UK commercial real estate (CRE) market, we propose the use of Amazon book reviews for real estate related products. Our analysis has shown, that the use of more than 200,000 book reviews, can train different supervised learning algorithms, which in turn, can capture the sentiment and more importantly, it can help predict the direct commercial real estate market trends
Low-pass genome sequencing-based detection of absence of heterozygosity: validation in clinical cytogenetics
No full textPurpose: Absence of heterozygosity (AOH) is a genetic characteristic known to cause human genetic disorders through autosomal recessive or imprinting mechanisms. However, the analysis of AOH via low-pass genome sequencing (GS) is yet to be clinically available.Methods: Low-pass GS (4-fold) with different types of libraries was performed on 17 clinical samples with previously ascertained AOH by chromosomal microarray analysis (CMA). In addition, AOH detection was performed with low-pass GS data in 1,639 cases that had both GS and high-probe-density CMA data available from the 1000 Genomes Project. Cases with multiple AOHs (coefficient of inbreeding F ≥1/32) or terminal AOHs ≥5-Mb (suspected uniparental disomy) were reported based on guidelines of the American College of Medical Genetics and Genomics.Results: Low-pass GS revealed suspected segmental UPD and multiple AOHs (F≥1/32) in nine and eight clinical cases, respectively, consistent with CMA. Among the 1,639 samples, low-pass GS not only consistently detected multiple AOHs (F≥1/32) in 18 cases, but also reported 60 terminal AOHs in 44 cases including four mosaic AOHs at a level ranging from 50% to 75%.Conclusion: Overall, our study demonstrates the feasibility of AOH analysis (≥5-Mb) with low-pass GS data and shows high concordance compared with CMA.<br/
Towards a Postcolonial Critical Realism
No full textThis article proposes postcolonial critical realism (PCR) as an ontological framework that explains the structuring relationship between racialised, colonial discourses and the social world. Beginning with the case study of the global climate crisis, it considers how scholars and activists have made sense of the present crisis, and how their discourses reflect and reproduce the climate crisis at large. To theorise the relationship between racialised, power-laden discourses and material reality, it derives five tenets of PCR: first, colonial discourses underlie, and interact with, material structures; second, coloniality is global and made visible through differential events and experiences; third, subaltern lived experiences reveal the nature of reality at large; fourth, coloniality is power-laden, sticky, and often invisible; and finally, decolonisation must target all three domains of the social world and their interactions. The article concludes by considering how this framework might enrich anticolonial thought in the social sciences, as well as social movements
Modelling finger propagation in elasto-rigid channels
No full textWe conduct a theoretical study of a two-phase-fluid-structure interaction problem in which air is driven at constant volume flux into a liquid-filled Hele-Shaw channel whose upper boundary is an elastic sheet. A depth-averaged model in the frame of reference of the advancing air-liquid interface is used to investigate the steady and unsteady interface propagation modes via numerical simulation. In slightly collapsed channels, the steadily-propagating interface adopts a shape that is similar to the classic Saman{ Taylor finger in rigid Hele-Shaw cells. As the level of initial collapse increases the induced gradients in channel depth alter the morphology of the propagating finger and promote a variety of instabilities from tip-splitting to small-scale fingering on the curved interface, in qualitative agreement with experiments. The model has a complex solution structure with a wide range of stable and unstable, steady and time-periodic modes, many of which have similar driving pressures. We find good quantitative agreement between our model and the experimental data of Ducloue et al. (J. Fluid Mech. vol. 819, 2017, p 121) for the finger width, sheet profile and finger pressure, provided that corrections to account for the presence of liquid films on the upper and lower walls of the channel are included in the model
Natural Killer cell immune synapse formation and cytotoxicity are controlled by tension of the target interface
No full textNatural Killer (NK) cells can kill infected or transformed cells via a lytic immune synapse. Diseased cells may exhibit altered mechanical properties but how this impacts NK cell responsiveness is unknown. We report that human NK cells were stimulated more effectively to secrete granzymes A and B, FasL, granulysin and IFNγ, by stiff (142 kPa) compared to soft (1 kPa) planar substrates. To create surrogate spherical targets of defined stiffness, sodium alginate was used to synthesise soft (9 kPa), medium (34 kPa), or stiff (254 kPa) cell-sized beads, coated with antibodies against activating receptor NKp30 and the integrin LFA-1. Against stiff beads, NK cells showed increased degranulation. Polarisation of the microtubule-organising centre (MTOC) and lytic granules were impaired against soft targets, which instead resulted in the formation of unstable kinapses. Thus, by varying target stiffness to characterise the mechanosensitivity of immune synapses, we identify soft targets as a blind spot in NK cell recognition
Negative catalysis or non-Bell-Evans-Polanyi reactivity by metalloenzymes: Examples from mononuclear heme and non-heme iron oxygenases
No full textThere are many examples in bioinorganic chemistry, where metalloenzymes produce different reaction products than analogous biomimetic model complexes despite them having the same transition metal and first-coordination sphere environment. As a result, a lot of research has been devoted to the understanding of the effect of the first- and second coordination sphere of catalytic reaction centers. Thermodynamically, catalysis should follow the Bell-Evans-Polanyi principle, where the product with the largest driving force gives the lowest reaction barrier and consequently highest reaction rate and dominant reaction products. However, there are many examples in the literature, where the dominant products of an enzymatic reaction do not correspond to the reaction process with the largest exothermicity. In general, catalysis that follows the Bell-Evans-Polanyi principle is designated positive catalysis, whereas when products are obtained from non-Bell-Evans-Polanyi reactivity, it is defined as negative catalysis. In enzymes; however, the first- and second-coordination sphere determines whether positive or negative catalysis happens but many intricate details on how selectivities are reversed are still unknown. In this review paper, we cover recent advances on enzyme understanding where negative catalysis is dominant over positive catalysis. We show that the enzyme can achieve this feat, e.g., through the positioning of substrate and oxidant that then gives the desired product distributions. In particular, often the substrate is positioned such that the desired group of the substrate is positioned as close as possible to the oxidant, while unwanted activation channels are blocked by electrostatic perturbations or shielded by protein residues. Furthermore, recent work has shown that reactivity patterns in enzymes can also be influenced by long-range electrostatic interactions like an electric dipole field that can weaken or strengthen chemical bonds through long-range polarization effects. As a result of these electric field effects and long-range electrostatic interactions, enzymes can react through negative catalysis, where a thermodynamically less likely process gives the dominant products. In this review paper, we define and describe positive and negative catalysis in enzymes and compare structure and reactivity with biomimetic and homogeneous catalysts for a number of mononuclear iron-type enzymes including the cytochromes P450 and non-heme iron dioxygenases
A three-dimensional phase-field lattice Boltzmann method for incompressible two-components flows
No full textIn this paper, a lattice Boltzmann model for the coupled Allen-Cahn-Navier-Stokes equations in three dimensions is presented. Two equations are solved: one for the fluid velocity and one for the order parameter. Both are written within the general multiple-relaxation-time framework, where all the equilibrium and forcing terms are described by using the full set of Hermite polynomials. The resultant practical implementation is compact. The gradient of the order parameter can be computed by the non-local finite differences or the local central moments. The latter suffers from grid-scale oscillations. The very good accuracy properties are demonstrated against nine well-consolidated benchmark tests. Specifically, two groups of tests are tackled. In the former, the velocity field is superimposed. Hence, only the equation for the evolution of the order parameter is solved. These numerical experiments demonstrate the ability of the proposed scheme to capture the correct evolution of the interface. In the latter, two immiscible fluids are considered and the two equations are solved. Simulations of the vertical penetration of a wedge-shaped body, two- and three-dimensionalRayleigh-Taylor instability prove that two-fluids systems can be successfully simulated by our approach
Does the age of pharmaceuticals matter? Undetectable hydrate seeds impact hydration behaviour
No full textA study on the hydration behaviour of fluconazole demonstrates that both sample age and polymorphic form impacted the drugs kinetic stability to hydration. For two of the polymorphs, aged samples were found to hydrate more readily than fresh samples. The aging effect was attributed to the formation of monohydrate (MH) crystals over time. The MH, despite being initially undetectable, had a seeding effect, thus impacting the hydration kinetics
A prospective longitudinal study of chronic pulmonary aspergillosis in pulmonary tuberculosis in Indonesia (APICAL)
No full textObjectives: Chronic pulmonary aspergillosis (CPA) can complicate recovery from pulmonary tuberculosis (TB). CPA may also be misdiagnosed as bacteriologically-negative TB. This study aimed to determine the incidence of CPA in patients treated for TB in Indonesia; a country with a high incidence of TB. Methods: In this prospective, longitudinal cohort study in patients treated for pulmonary TB, clinical, radiological and laboratory findings were analysed. Sputum was collected for fungal culture and TB PCR. Patients were assessed at baseline (0-8 weeks) and at the end (5-6 months) of TB therapy. CPA diagnosis was based on symptoms (>3 months), characteristic radiological features and positive Aspergillus serology, and categorized as proven, probable and possible. Results: Of the 216 patients recruited, 128 (59%) were followed up until end of TB therapy. At baseline, 91 (42%) had microbiological evidence for TB. Aspergillus-specific IgG was positive in 64 (30%) patients and went from negative to positive in 16 (13%) patients during TB therapy. The incidence of proven and probable CPA at baseline was 6% (n=12) and 2% (n=5) and end of TB therapy 8% (n=10) and 5% (n=7), respectively. Six patients (2 with confirmed TB) developed an aspergilloma. Diabetes mellitus was a significant risk factor for CPA (p=0.040). Persistent cough (n=5, 50%; p=0.005) and fatigue (n=6, 60%; p=0.001) were the most common symptoms in CPA. Conclusion: CPA should be considered a relatively frequent differential diagnosis in patients with possible or proven TB in Indonesia. Lack of awareness and limited access to Aspergillus-specific IgG tests and CT imaging are obstacles in establishing a CPA diagnosis
Integral effects of initial fluids configuration and wettability alteration on remaining saturation: characterization with X-ray micro-computed tomography
No full textWettability alteration is the key process in low salinity waterflooding to enhance oil recovery. However, wettability alteration cannot necessarily lead to better oil recovery as other factors such as initial fluids morphology plays critical roles. We used Micro-CT X-ray imaging to investigate the effects of initial water morphology and wettability alteration on final remaining oil saturation and oil ganglia size distribution. The results show that presence of percolating water pathways impedes the oil recovery and oil can be produced mostly from large pores at tertiary mode, whereas the secondary low salinity waterflooding unlocks oil from a much broader range of pores. Moreover, the in-situ contact angles decrease towards less oil-wet regardless of initial water saturation, suggesting that wettability alteration is not dependent on the initial water saturation. We observed that at the end of secondary low salinity water flooding, larger trapped ganglia were identified which is in agreement with the ganglia mobilisation theory. This work provided novel insights into the source of additional oil recovery during low salinity waterflooding and addressed the unrecognized role of initial fluids morphology in hydrocarbon recovery and multiphase flow