Onset of glassiness in two-dimensional ring polymers: Interplay of stiffness and crowding.

The effect of ring stiffness and pressure on the glassy dynamics of a thermal assembly of two-dimensional ring polymers is investigated using extensive coarse-grained molecular dynamics simulations. In all cases, dynamical slowing down is observed with increasing pressure, and thereby, a phase space for equilibrium dynamics is identified in the plane of the obtained monomer density and ring stiffness. When the rings are highly flexible, i.e., have low ring stiffness, glassiness sets in via the crowding of crumpled polymers, which take on a globular form. In contrast, at large ring stiffness, when the rings tend to have large asphericity under compaction, we observe the emergence of local domains having orientational ordering at high pressures. Therefore, our simulations highlight how varying the deformability of rings leads to contrasting mechanisms in driving the system toward the glassy regime.

Multi-faceted dysregulated immune response for COVID-19 infection explaining clinical heterogeneity.

Clinical heterogeneity and varied prognosis are well noted for SARS-CoV-2 infection. Altered immune response is a major feature for the adverse prognosis however focus on altered immune response has been primarily limited to hyper-inflammatory responses like Cytokine storm. A deeper understanding of viral pathobiology and the interplay of innate and adaptive immune cells against SARS-CoV-2 infection is essential to optimize intervention strategy and future preparedness for SARS-CoV-2 or its related viral diseases. To uncover the immunological signatures driving the progression of SARS-CoV-2 infection, we performed an extensive immunophenotype on blood samples from 79 hospitalized patients with mild/moderate to severe infections as well as from healthy controls and recovered donors to understand the interplay between innate and adaptive responses impacting severity and prognosis. We observed multifarious immune dysregulation, varied across patients of the clinical spectrum. We observed 4 major dysregulations of immune phenotypes 1) depletion of M1φ (impaired antiviral response as APC), 2) immune suppression/exhaustion via activation of repressor like CD4+/CD8+PD1, TIM3, LAG3 3) inappropriate differentiation of lymphocyte (extreme elevated proportion of CD4 naive, memory B and T cells along with reduction of inflammatory activator like TLR2/4/TIGIT) and 4) cytokine storm. Our results show the identification of biomarkers to differentiate the different trajectories for SARS-CoV-2 infection.

Knowledge, attitude, and practice patterns of Indian ophthalmologists regarding medicolegal issues.

PURPOSE: To assess the knowledge, attitude, and practice patterns (KAPP) of Indian ophthalmologists regarding medicolegal issues using an initial survey. METHODS: An online form was circulated among Indian ophthalmologists of all ages over social media and email by the Young Ophthalmologists Society of India (YOSI) and its medicolegal working group. Anonymous responses were obtained and analyzed for each question. The questionnaire comprised questions about demographic details, KAPP of medicolegal issues including how to deal with medicolegal issues (if faced), medical indemnity insurance, deviation from the recommended minimum sum assured (Rs. 1 crore for Indian ophthalmologists), and legal service providers. RESULTS: A total of 109 responses were obtained. The majority of the respondents were male (60, 55%). More than 50% of respondents (58, 53.2%) were younger than 35 years. More than one-fourth of the respondents were private practitioners (29, 27%), and the majority were of senior consultant designation (45, 41%). Around 80% of respondents (89, 81.6%) were aware of professional indemnity insurance; however, only 54% (n = 59) bought the insurance cover. A majority of the respondents (38, 64.4%) had an indemnity cover of a maximum of Rs. 50 lacs. Only 20% of respondents were aware of the expert body at the state/national level that deals with medicolegal cases. Thirty percent of respondents recommended the ideal cover amount to be more than Rs. 1 crore. CONCLUSION: The current survey highlights the dismally low rate of awareness of medicolegal issues among ophthalmologists. Specifically, a majority of Indian ophthalmologists surveyed did not have recommended minimum insured cover for professional indemnity insurance. Larger studies are needed to further explore KAPP of Indian ophthalmologists in various medicolegal issues.

Augmentation of anti-proliferative efficacy of quercetin encapsulated chitosan nanoparticles by induction of cell death via mitochondrial membrane permeabilization in oral cancer.

Quercetin (QCT), an antioxidant plant flavonoid, is known to impart prominent anti-cancer properties. However, its clinical application as a potential drug is hindered owing to its hydrophobicity, extensive metabolism, low absorption, and rapid elimination. The drawbacks of these phytochemical-based therapies can be addressed using nanotechnology-based drug delivery systems. In this study, we sought to develop chitosan nanoparticles (CSNPs) as the drug vehicle for encasing quercetin (QCT-CSNPs) and further investigate its anti-tumor potential against human oral cancer cell line Cal33. Our findings indicate that the average particle diameter of the formulated chitosan nanoparticles was around 100 nm, and they had a spherical structure, as per the TEM and FESEM images. The efficient entrapment of quercetin inside the CSNPs matrix is confirmed by XRD, UV-Vis spectrophotometry, FTIR, and DSC analysis. The in vitro cell cytotoxicity study against Cal33 oral cancer cells revealed that QCT-CSNPs exhibited superior toxicity compared to free QCT post-24-hour treatment. The improved anti-cancer efficacy of QCT-CSNPs was further confirmed by enhanced cellular apoptosis, colony formation inhibition, migration inhibition, and chromatin condensation. Moreover, the mitochondrial dysfunction and enhanced ROS (Reactive oxygen species) production indicated mitochondrial-mediated cell death in QCT-CSNPs treated Cal33 cells. In conclusion, our data suggest that quercetin-encapsulated chitosan nanoparticles may serve as a potential drug candidate against oral cancer.

Novel Mixed-Dimensional hBN-Passivated Silicon Nanowire Reconfigurable Field Effect Transistors: Fabrication and Characterization.

This work demonstrates the novel concept of a mixed-dimensional reconfigurable field effect transistor (RFET) by combining a one-dimensional (1D) channel material such as a silicon (Si) nanowire with a two-dimensional (2D) material as a gate dielectric. An RFET is an innovative device that can be dynamically programmed to perform as either an n- or p-FET by applying appropriate gate potentials. In this work, an insulating 2D material, hexagonal boron nitride (hBN), is introduced as a gate dielectric and encapsulation layer around the nanowire in place of a thermally grown or atomic-layer-deposited oxide. hBN flake was mechanically exfoliated and transferred onto a silicon nanowire-based RFET device using the dry viscoelastic stamping transfer technique. The thickness of the hBN flakes was investigated by atomic force microscopy and transmission electron microscopy. The ambipolar transfer characteristics of the Si-hBN RFETs with different gating architectures showed a significant improvement in the device's electrical parameters due to the encapsulation and passivation of the nanowire with the hBN flake. Both n- and p-type characteristics measured through the top gate exhibited a reduction of hysteresis by 10-20 V and an increase in the on-off ratio (ION/IOFF) by 1 order of magnitude (up to 108) compared to the values measured for unpassivated nanowire. Specifically, the hBN encapsulation provided improved electrostatic top gate coupling, which is reflected in the enhanced subthreshold swing values of the devices. For a single nanowire, an improvement up to 0.97 and 0.5 V/dec in the n- and p-conduction, respectively, is observed. Due to their dynamic switching and polarity control, RFETs boast great potential in reducing the device count, lowering power consumption, and playing a crucial role in advanced electronic circuitry. The concept of mixed-dimensional RFET could further strengthen its functionality, opening up new pathways for future electronics.

Density-dependent relationship between changes in ultrasonic wave velocities, effective stress, and petrophysical-elastic properties of sandstone.

The present study aims to reveal the importance of density as a moderator variable in interpretation of possible relationships between variations in compressional and shear wave velocities (ΔVp and ΔVs), effective stress, and rock's petrophysical and elastic properties. Towards this end, fourteen subsurface sandstone samples were collected and analyzed through the measurement of ultrasonic wave velocities at standard and reservoir conditions within a Triaxial-testing cell. The results were interpreted for two groups, i.e., low density (LD) and high density (HD) samples, where greater ΔVp and ΔVs were observed for the HD group samples that have similar average porosity and permeability compared to samples from LD group. Effective stress exhibits better fit with ΔVp and ΔVs for the LD compared to HD group samples. Density was revealed to be well fitted with ΔVp of LD and ΔVs of HD samples. Porosity exhibits good fit with ΔVs of LD and permeability exhibits good fit with ΔVp of both LD and HD groups. Also, variations in estimated elastic limit (ΔEd) is well matched with ΔVs, while changes in estimated Poisson's ratio (Δν) manifests a good fitting with ΔVp. Finally, variation in deviatoric stresses from triaxial tests is in a good agreement with ΔVp. The results of this study provide convenient insights for conversion of wave velocities and elastic properties between standard and reservoir conditions.

Maxillary Mucinous Adenocarcinoma Mimicking a Lesion of Endodontic Origin: A Rare Case Report.

Periapical lesions of endodontic origin are fairly common in the oral cavity in association with tooth pulp infection. Most of these lesions will resolve with adequate root canal treatment and rarely cause suspicion of more insidious disease. Most clinicians tend to skip histopathological examination in cases where the lesion is excised or curetted. We present a rare case of mucinous adenocarcinoma in association an endodontically treated maxillary discoloured central incisor in a 38 year old patient with a history of root canal treatment about 15 years ago. Root canal re-treatment and wide excision was performed. Histology showed epithelial islands suggestive of a neoplasm. Immunohistochemistry was positive for CK7 and S100. Metastasis was ruled out and no evidence of recurrence has been noted in the 12-month follow up period. It is emphasized that any tissue removed from the surgical site should be analysed microscopically. (EEJ-2022-01-013).

A Brief Introduction to Magnetoencephalography (MEG) and Its Clinical Applications.

Magnetoencephalography (MEG) plays a pivotal role in the diagnosis of brain disorders. In this review, we have investigated potential MEG applications for analysing brain disorders. The signal-to-noise ratio (SNRMEG = 2.2 db, SNREEG < 1 db) and spatial resolution (SRMEG = 2−3 mm, SREEG = 7−10 mm) is higher for MEG than EEG, thus MEG potentially facilitates accurate monitoring of cortical activity. We found that the direct electrophysiological MEG signals reflected the physiological status of neurological disorders and play a vital role in disease diagnosis. Single-channel connectivity, as well as brain network analysis, using MEG data acquired during resting state and a given task has been used for the diagnosis of neurological disorders such as epilepsy, Alzheimer's, Parkinsonism, autism, and schizophrenia. The workflow of MEG and its potential applications in the diagnosis of disease and therapeutic planning are also discussed. We forecast that computer-aided algorithms will play a prominent role in the diagnosis and prediction of neurological diseases in the future. The outcome of this narrative review will aid researchers to utilise MEG in diagnostics.

Polarity-Tunable Photocurrent through Band Alignment Engineering in a High-Speed WSe2/SnSe2 Diode with Large Negative Responsivity.

Excellent light-matter interaction and a wide range of thickness-tunable bandgaps in layered vdW materials coupled by the facile fabrication of heterostructures have enabled several avenues for optoelectronic applications. Realization of high photoresponsivity at fast switching speeds is a critical challenge for 2D optoelectronics to enable high-performance photodetection for optical communication. Moving away from conventional type-II heterostructure pn junctions towards a WSe2/SnSe2 type-III configuration, we leverage the steep change in tunneling current along with a light-induced heterointerface band shift to achieve high negative photoresponsivity, while the fast carrier transport under tunneling results in high speed. In addition, the photocurrent can be controllably switched from positive to negative values, with ∼104× enhancement in responsivity, by engineering the band alignment from type-II to type-III using either the drain or the gate bias. This is further reinforced by electric-field dependent interlayer band structure calculations using density functional theory. The high negative responsivity of 2 × 104 A/W and fast response time of ∼1 µs coupled with a polarity-tunable photocurrent can lead to the development of next-generation multifunctional optoelectronic devices.

Controlled Silicidation of Silicon Nanowires Using Flash Lamp Annealing.

Among other new device concepts, nickel silicide (NiSix)-based Schottky barrier nanowire transistors are projected to supplement down-scaling of the complementary metal-oxide semiconductor (CMOS) technology as its physical limits are reached. Control over the NiSix phase and its intrusions into the nanowire is essential for superior performance and down-scaling of these devices. Several works have shown control over the phase, but control over the intrusion lengths has remained a challenge. To overcome this, we report a novel millisecond-range flash lamp annealing (FLA)-based silicidation process. Nanowires are fabricated on silicon-on-insulator substrates using a top-down approach. Subsequently, Ni silicidation experiments are carried out using FLA. It is demonstrated that this silicidation process gives unprecedented control over the silicide intrusions. Scanning electron microscopy and high-resolution transmission electron microscopy are performed for structural characterization of the silicide. FLA temperatures are estimated with the help of simulations.

Brain-Computer Interfacing Using Functional Near-Infrared Spectroscopy (fNIRS).

Functional Near-Infrared Spectroscopy (fNIRS) is a wearable optical spectroscopy system originally developed for continuous and non-invasive monitoring of brain function by measuring blood oxygen concentration. Recent advancements in brain-computer interfacing allow us to control the neuron function of the brain by combining it with fNIRS to regulate cognitive function. In this review manuscript, we provide information regarding current advancement in fNIRS and how it provides advantages in developing brain-computer interfacing to enable neuron function. We also briefly discuss about how we can use this technology for further applications.

Efficacy and Cost-Effectiveness of Anti-VEGF for Treating Diabetic Retinopathy in the Indian Population.

PURPOSE: In the present study, we aimed to evaluate the efficacy, safety, and cost-effectiveness of the anti-vascular endothelial growth factor (anti-VEGF), namely ranibizumab (RBZ) or bevacizumab (BVZ), after either focal or grid or scatter laser photocoagulation, for the treatment of diabetic macular edema (DME) in the Indian population. METHODS: Retrospective data were collected in the Regional Institute of Ophthalmology, Kolkata, India between January 2018 and June 2019. Seventy-seven eyes received 3 consecutive monthly intravitreal injections of RBZ (0.5 mg) and were followed by prompt laser photocoagulation (within 7-10 days after the third injection). Similarly, 51 eyes received 3 consecutive monthly intravitreal injections of BVZ (1.25 mg), an off-label drug, and were followed by prompt laser therapy. Safety assessments of the therapy, as well as surrogate markers of biochemical derangements related to diabetic retinopathy (DR), were also investigated at the end of 12 months. RESULTS: Seventy-seven subjects who were given a treatment of RBZ+laser therapy showed average 6.87±5.53 letters gain in their best-corrected visual acuity (BCVA) score, whereas the ones treated with off-label BVZ+ laser therapy demonstrated improvement in BCVA of an average 6.82±5.76 letters in "Early Treatment Diabetic Retinopathy Study" (ETDRS) chart. The study also highlights the cost-effectiveness of both RBZ+laser and BVZ+laser therapies for the treatment of DME in DR. The results demonstrated that a subject has to pay 20.951 times more cost (in INR) for RBZ+laser therapy compared to BVZ+laser therapy, to get an almost similar outcome. CONCLUSION: BVZ is found to be the more attractive option for treating DME in DR for its cost-friendliness over RBZ in terms of BCVA outcome, as well as the safety perspectives, at least for the economically backward population in developing countries, like India.

Enhanced responsivity and detectivity of fast WSe2 phototransistor using electrostatically tunable in-plane lateral p-n homojunction.

Layered transition metal dichalcogenides have shown tremendous potential for photodetection due to their non-zero direct bandgaps, high light absorption coefficients and carrier mobilities, and ability to form atomically sharp and defect-free heterointerfaces. A critical and fundamental bottleneck in the realization of high performance detectors is their trap-dependent photoresponse that trades off responsivity with speed. This work demonstrates a facile method of attenuating this trade-off by nearly 2x through integration of a lateral, in-plane, electrostatically tunable p-n homojunction with a conventional WSe2 phototransistor. The tunable p-n junction allows modulation of the photocarrier population and width of the conducting channel independently from the phototransistor. Increased illumination current with the lateral p-n junction helps achieve responsivity enhancement upto 2.4x at nearly the same switching speed (14-16 µs) over a wide range of laser power (300 pW-33 nW). The added benefit of reduced dark current enhances specific detectivity (D*) by nearly 25x to yield a maximum measured flicker noise-limited D* of 1.1×1012 Jones. High responsivity of 170 A/W at 300 pW laser power along with the ability to detect sub-1 pW laser switching are demonstrated.

All-Electrical High-Sensitivity, Low-Power Dual-Mode Gas Sensing and Recovery with a WSe2/MoS2 pn Heterodiode.

Two-dimensional MoS2 gas sensors have conventionally relied on a change in field-effect-transistor (FET) channel resistance or in the Schottky contact/pn homojunction barrier. We demonstrate an enhancement in sensitivity (6×) and dynamic response along with a reduction in detection limit (8×) and power (104×) in a gate-tunable type-II WSe2(p)/MoS2(n) heterodiode gas sensor over an MoS2 FET on the same flake. Measurements for varying NO2 concentration, gate bias, and MoS2 flake thickness, reinforced with first-principles calculations, indicate dual-mode operation due to (i) a series resistance-based exponential change in the high-bias thermionic current (high sensitivity), and (ii) a heterointerface carrier concentration-based linear change in near-zero-bias interlayer recombination current (low power) resulting in sub-100 µW/cm2 power consumption. Fast and gate-bias tunable recovery enables an all-electrical, room-temperature dynamic operation. Coupled with the sensing of trinitrotoluene (TNT) molecules down to 80 ppb, this study highlights the potential of the WSe2/MoS2 pn heterojunction as a simple, low-overhead, and versatile chemical-sensing platform.

Imaging current distribution in a topological insulator Bi2Se3 in the presence of competing surface and bulk contributions to conductivity.

Two-dimensional (2D) topological surface states in a three-dimensional topological insulator (TI) should produce uniform 2D surface current distribution. However, our transport current imaging studies on Bi2Se3 thin film reveal non-uniform current sheet flow at 15 K with strong edge current flow. This is consistent with other imaging studies on thin films of Bi2Se3. In contrast to strong edge current flow in thin films, in single crystal of Bi2Se3 at 15 K our current imaging studies show the presence of 3.6 nm thick uniform 2D sheet current flow. Above 70 K, this uniform 2D sheet current sheet begins to disintegrate into a spatially non-uniform flow. The flow becomes patchy with regions having high and low current density. The area fraction of the patches with high current density rapidly decreases at temperatures above 70 K, with a temperature dependence of the form [Formula: see text]. The temperature scale of 70 K coincides with the onset of bulk conductivity in the crystal due to electron doping by selenium vacancy clusters in Bi2Se3. Thus our results show a temperature dependent competition between surface and bulk conductivity produces a temperature dependent variation in uniformity of current flow in the topological insulator.

Near-Direct Bandgap WSe2/ReS2 Type-II pn Heterojunction for Enhanced Ultrafast Photodetection and High-Performance Photovoltaics.

Pn heterojunctions comprising layered van der Waals (vdW) semiconductors have been used to demonstrate current-rectifiers, photodetectors, and photovoltaic devices. However, a direct or near-direct heterointerface bandgap for enhanced photogeneration in high light-absorbing few-layer vdW materials remains unexplored. In this work, for the first time, density functional theory calculations show that the heterointerface of few-layer group-6 transition metal dichalcogenide (TMD) WSe2 with group-7 ReS2 results in a sizable (0.7 eV) near-direct type-II bandgap. The interlayer IR bandgap is confirmed through IR photodetection, and microphotoluminescence measurements demonstrate type-II alignment. Few-layer flakes exhibit ultrafast response time (5 µs), high responsivity (3 A/W), and large photocurrent-generation and responsivity-enhancement at the hetero-overlap region (10-100×). Large open-circuit voltage of 0.64 V and short-circuit current of 2.6 µA enable high output electrical power. Finally, long-term air-stability and facile single contact metal fabrication process make the multifunctional few-layer WSe2/ReS2 heterostructure diode technologically promising for next-generation optoelectronics.

A Scoping Insight on Potential Prophylactics, Vaccines and Therapeutic Weaponry for the Ongoing Novel Coronavirus (COVID-19) Pandemic- A Comprehensive Review.

The emergence of highly virulent CoVs (SARS-CoV-2), the etiologic agent of novel ongoing "COVID-19" pandemics has been marked as an alarming case of pneumonia posing a large global healthcare crisis of unprecedented magnitude. Currently, the COVID-19 outbreak has fueled an international demand in the biomedical field for the mitigation of the fast-spreading illness, all through the urgent deployment of safe, effective, and rational therapeutic strategies along with epidemiological control. Confronted with such contagious respiratory distress, the global population has taken significant steps towards a more robust strategy of containment and quarantine to halt the total number of positive cases but such a strategy can only delay the spread. A substantial number of potential vaccine candidates are undergoing multiple clinical trials to combat COVID-19 disease, includes live-attenuated, inactivated, viral-vectored based, sub-unit vaccines, DNA, mRNA, peptide, adjuvant, plant, and nanoparticle-based vaccines. However, there are no licensed anti-COVID-19 drugs/therapies or vaccines that have proven to work as more effective therapeutic candidates in open-label clinical trial studies. To counteract the infection (SARS-CoV-2), many people are under prolonged treatment of many chemical drugs that inhibit the PLpro activity (Ribavirin), viral proteases (Lopinavir/Ritonavir), RdRp activity (Favipiravir, Remdesivir), viral membrane fusion (Umifenovir, Chloroquine phosphate (CQ), Hydroxychloroquine phosphate (HCQ), IL-6 overexpression (Tocilizumab, Siltuximab, Sarilumab). Mesenchymal Stem Cell therapy and Convalescent Plasma Therapy have emerged as a promising therapeutic strategy against SARS-CoV-2 virion. On the other hand, repurposing previously designed antiviral agents with tolerable safety profile and efficacy could be the only promising approach and fast response to the novel virion. In addition, research institutions and corporations have commenced the redesign of the available therapeutic strategy to manage the global crisis. Herein, we present succinct information on selected anti-COVID-19 therapeutic medications repurposed to combat SARS-CoV-2 infection. Finally, this review will provide exhaustive detail on recent prophylactic strategies and ongoing clinical trials to curb this deadly pandemic, outlining the major therapeutic areas for researchers to step in.

Effect of regional wind circulation and meteorological factors on long-range migration of mustard aphids over indo-gangetic plain.

Mustard aphids are a serious problem for Brassica oilseed in India causing up to 90% of the crop damage. It was hypothesized that Aphids migrate into the Indo Gangetic plain (IGP) from hilly regions of every year. Exact source and migration pattern of this pest is unknown till date. During their long range migration they infested various places over IGP, which fall on their way of migration. The wind, blown from the hilly regions helps aphids to migrate. Meteorological parameters play a crucial role in this migration of aphids. In this study, we have done the 24 hours air-mass backward trajectory at 100 m above ground level (agl) to detect the source regions of mustard aphids. We have found that mainly Western Himalayan hilly regions act as the source of mustard aphids for IGPs. The dependence upon the micro-meteorological parameters and population dynamics are analyzed and discussed elaborately in this work. In this study, we have proposed the 'Hop and Fly' behavior of mustard aphid and further discussed how this migrating behavior could help us to reduce the yield loss of Brassica.

Prominent physical inactivity in acute dementia care: Psychopathology seems to be more important than the dose of sedative medication.

INTRODUCTION: To objectively quantify patients' physical activity and analyze the relationships between physical activity levels, psychopathology, and sedative medication in acute hospital dementia care. MATERIALS AND METHODS: In this cross-sectional study, we assessed the patients' physical activity based on data collection by hybrid motion sensors attached on their lower back. Daily doses of antipsychotics have been converted to olanzapine-equivalents and daily benzodiazepine medication is reported as diazepam-equivalents. We assessed patients' neuropsychiatric symptoms with the Neuropsychiatric Inventory and the Cohen-Mansfield Agitation Inventory. RESULTS: We analyzed motion sensor data from 64 patients (MMSE M = 18.6). On average, patients were lying for 11.5 hours, sitting/standing sedentary for 10.3 hours, sitting/standing active for 1.0 hours, and walking for 1.2 hours per day. The analysis revealed no correlations between patients' physical activity and antipsychotic or benzodiazepine medication. More severe neuropsychiatric symptoms were associated with a decrease in the patients' physical activity (r = .32, P = .01). In particular, patients with apathy symptoms were less physically active than patients without apathy symptoms. DISCUSSION: The results reveal that most of the patients in acute dementia care had very low levels of physical activity. Their physical inactivity may be due to the severity of their neuropsychiatric symptoms, especially apathy. Antipsychotic and benzodiazepine medication appeared to have less impact on patients' physical activity. Dementia care should pay more attention to prevent physical inactivity in patients.

Statistical learning of mobility patterns from long-term monitoring of locomotor behaviour with body-worn sensors.

Long term monitoring of locomotor behaviour in humans using body-worn sensors can provide insight into the dynamical structure of locomotion, which can be used for quantitative, predictive and classification analyses in a biomedical context. A frequently used approach to study daily life locomotor behaviour in different population groups involves categorisation of locomotion into various states as a basis for subsequent analyses of differences in locomotor behaviour. In this work, we use such a categorisation to develop two feature sets, namely state probability and transition rates between states, and use supervised classification techniques to demonstrate differences in locomotor behaviour. We use this to study the influence of various states in differentiating between older adults with and without dementia. We further assess the contribution of each state and transition and identify the states most influential in maximising the classification accuracy between the two groups. The methods developed here are general and can be applied to areas dealing with categorical time series.