Local Index Research Articles

Dynamic development of cohesive devices in English as a second language writing

Abstract The dearth of research examining the progression of cohesion in L2 writing through a time-series research design is evident. Therefore, the current study employs the Complex Dynamic Systems Theory to explore the evolution of cohesive devices in L2 writing. Thirty advanced-level L2 writers from a US university participated over a semester, providing 210 written samples at seven measurement points. Analysis of these samples, utilizing 40 cohesion indices from the Tool for the Automatic Analysis of Cohesion, revealed significant improvement in eight cohesion indices (three local, four global, and one text cohesion indices) with large effect sizes. However, time-series analyses indicated nonlinear trends and variability. Additionally, a positive association was found between two local cohesion indices (lexical and semantic overlap) at the initial and final measurement points. The findings demonstrate the multifaceted developmental trajectories and complexities evident in L2 learners’ approaches and carry important implications for L2 writing instruction and assessment.

Key Factors behind the Dynamic Stability of Pairs of Egyptian Vultures in Continental Spain.

Conservation science aims to identify the factors influencing the distribution of threatened species, thereby permitting the implementation of effective management strategies. This is key for long-lived species that require long-term monitoring such as the worldwide endangered Egyptian vulture (Neophron percnopterus). We studied temporal and spatial variations in the distribution of breeding pairs and examined the intrinsic and anthropic factors that may be influencing the abundance of breeding territories in continental Spain. Based on the census data of breeding pairs from 2000, 2008, and 2018, we used Rank Occupancy-Abundance Profiles to assess the temporal stability of the population and identified the spatial heterogeneity through a Local Index of Spatial Autocorrelation analysis. The GLMs showed that the abundance distribution was mainly influenced by the abundance of griffon vultures (Gyps fulvus) and cattle at a regional scale. Nonparametric comparisons showed that the presence of wind farms had a significant negative effect on local breeding pairs abundance, but that supplementary feeding stations and food resource-related variables had a positive impact. In light of these findings, we recommend a hierarchical approach in future conservation programs involving actions promoting regional-scale food resource availability and highlight the need to address the negative impact of wind farms at local levels.

Artificial Neural Network-Based Voltage Stability Online Monitoring Approach for Distributed Generation Integrated Distribution System

Due to the growth of electric power demand and the intricacy of modern distribution system structure, the voltage stability issue is evolving as a critical problem in distribution grids. Therefore, it is imperative to investigate the corrective measures. In this paper, artificial neural network (ANN) based voltage stability online monitoring approach for distribution systems with distribution generators (DGs) is proposed. The proposed technique employs a local voltage stability index known as the stability index (SI) to identify the weak bus information, which is more effective compared to the conventional load margin techniques. Furthermore, the nonlinear relationship of the distribution grid control status and the resultant SI is mapped using ANN. From the installed distribution-level phasor measurement units (PMUs), the state parameters of buses can be obtained, and the resultant values of SI can be estimated. This approach can significantly enhance the computational speed of SI and evaluate the voltage stability measurement of distribution network in real-time, which assist the operator of the network in order to determine the operational condition and execute actions quickly. The proposed approach is applied on the modified IEEE 33 and IEEE 69-bus system with DGs. It is found that the computation time needed for assessment of voltage stability by CPF method is 16.2500 s and 21.8872 s whilst the computation time needed for the proposed method for the same assessment is 0.0677 s and 0.0749 s respectively for modified IEEE 33 and IEEE 69-bus system. This demonstrates that the proposed method has high accuracy and efficacy.

A DFT investigation of the catalytic oxidation of benzyl alcohol using graphene oxide.

Metal-free heterogeneous materials have attracted great interest due to their potential to facilitate various organic transformations in line with circular economy and green chemistry principles. Among various 2D materials, graphene oxide (GO) is considered an attractive material for numerous applications in physics, chemistry, biology, material sciences, and catalysis. Furthermore, graphene-based catalysts exhibit good catalytic activity toward the selective oxidation of benzyl alcohol to benzaldehyde or benzoic acid under eco-friendly conditions. In this regard, a theoretical investigation was carried out to study both catalytic oxidation reaction pathways (i.e., benzyl alcohols to aldehyde and to benzoic acid) using GO as an eco-friendly and metal-free catalyst. In this study, we report a theoretical investigation at the B3LYP/6-31G level to better understand the oxidation of benzyl alcohol using GO as a metal-free catalyst. The possible bond formation was investigated using the global and local reactivity indexes derived from Fukui functions. Furthermore, we performed a non-covalent interaction (NCI) analysis to unveil the stability and the interaction nature between both reagents and GO surface. The effect of the solvent on the oxidation efficiency was also performed and the results indicate that the solvent significantly affects the decrease of reactivity by increasing the activation barriers through oxidation reactions of benzyl alcohol. Additionally, the electron localization function (ELF) analysis was performed for all intermediates showing the ionic nature of the studied epoxide structure of GO and rules out any type of covalent interaction during the oxidation reaction of benzyl alcohol. All these obtained results are in good agreement with experimental observations and reveal that the epoxide functions on the graphene surface promote an excellent catalyst turnover.

A molecular electron density theory study of asymmetric Diels-Alder [4 + 2] reaction's mechanism of furan with three substituted alkynes (5-R substituted-3-(3-(phenylsulfonyl)-propioloyl)-oxazolidin-2-one).

The [4 +2 ] cycloaddition reactions between furan and three substituted alkynes (5-R-substituted-3-(3-(phenylsulfonyl)-propioloyl)-oxazolidin-2-one) have been investigated using the MEDT approach. Reactivity indices, reaction pathways, and activation energies are calculated. In an investigation of conceptual DFT indices, furan acts as a nucleophile, while the three substituted alkynes (5-R-substituted-3-(3-(phenylsulfonyl)-propioloyl)-oxazolidin-2-one) function as electrophiles in this reaction. The cycloaddition is regioiselective, as demonstrated by the activation and reaction energies, in clear agreement with the experiment's results. Hetero Diels-Alder [4 + 2] cycloadditions occur following a non-concerted two stages one-step molecular mechanism. For the purpose of this study, all calculations were performed using the Gaussian 09 software. Optimization was achieved through Berny's computational gradient optimization method, employing the B3LYP functional and the 6-31G(d) basis set. Analysis of both local and global reactivity indices provided insights into the reactivity tendencies of the reactants, distinguishing between electrophilic and nucleophilic characteristics via Parr functions. Frequency calculations were employed to identify and characterize stationary points, with transition states indicated by a single imaginary frequency and positive values of all frequencies for reactants and product. The electron localization function (ELF) was investigated using the Multiwfn software within the context of topological analyses.

Integrating survey and observer data improves the predictions of New Zealand spatio-temporal models

AbstractIn many situations, species distribution models need to make use of multiple data sources to address their objectives. We developed a spatio-temporal modelling framework that integrates research survey data and data collected by observers onboard fishing vessels while accounting for physical barriers (islands, convoluted coastlines). We demonstrated our framework for two bycatch species in New Zealand deepwater fisheries: spiny dogfish (Squalus acanthias) and javelinfish (Lepidorhynchus denticulatus). Results indicated that employing observer-only data or integrated data is necessary to map fish biomass at the scale of the New Zealand exclusive economic zone, and to interpolate local biomass indices (e.g., for the east coast of the South Island) in years with no survey but available observer data. Results also showed that, if enough survey data are available, fisheries analysts should: (1) develop both an integrated model and a model relying on survey-only data; and (2) for a given geographic area, ultimately choose the index produced with integrated data or the index produced with survey-only data based on the reliability of the interannual variability of the index. We also conducted a simulation experiment, which indicated that the predictions of our spatio-temporal models are virtually insensitive to the consideration of physical barriers.

Identification of Bird Habitat Restoration Priorities in a Central Area of a Megacity

Rapid global urbanization has caused habitat degradation and fragmentation, resulting in biodiversity loss and the homogenization of urban species. Birds play a crucial role as biodiversity indicators in urban environments, providing multiple ecosystem services and demonstrating sensitivity to changes in habitat. However, construction activities often disrupt urban bird habitats, leading to a decline in habitat quality. This paper proposes a framework for prioritizing habitat restoration by pinpointing bird hotspots that demand attention and considering the matching relationship between bird richness and habitat quality. Shanghai represents a typical example of the high-density megacities in China, posing a significant challenge for biodiversity conservation efforts. Utilizing the random forest (RF) model, bird richness patterns in central Shanghai were mapped, and bird hotspots were identified by calculating local spatial autocorrelation indices. From this, the habitat quality of hotspot areas was evaluated, and the restoration priority of bird habitats was determined by matching bird richness with habitat quality through z-score standardization. The results were as follows: (1) Outer-ring green spaces, large urban parks, and green areas along coasts or rivers were found to be the most important habitats for bird richness. Notably, forests emerged as a crucial habitat, with approximately 50.68% of the forested areas identified as hotspots. (2) Four habitat restoration types were identified. The high-bird-richness–low-habitat-quality area (HBR-LHQ), mainly consisting of grassland and urban construction land, was identified as a key priority for restoration due to its vulnerability to human activities. (3) The Landscape Shannon’s Diversity Index (SHDI) and Normalized Difference Vegetation Index (NDVI) are considered the most significant factors influencing the bird distribution. Our findings provide a scientifically effective framework for identifying habitat restoration priorities in high-density urban areas.

Stable isotopes reveal organic nitrogen pollution and cycling from point and non-point sources in a heavily cultivated (agricultural) Mediterranean river basin

The Pinios River Basin (PRB) is the most intensively cultivated area in Greece, which hosts numerous industries and other anthropogenic activities. The analysis of water samples collected monthly for ∼1 ½ years in eight monitoring sites in the PRB revealed nitrate pollution of organic origin extending from upstream to downstream and occurring throughout the year, masking the signal from the application of synthetic fertilizers. Nitrate concentrations reached up to 3.6 mg/l as NO3−-N, without exceeding the drinking water threshold of ∼11.0 mg/l (as NO3−-N). However, the water quality status was “poor” or “bad” in ∼50 % of the samples based on a local index, which considers the potential impact of nitrate on aquatic biological communities. The δ15Ν-ΝΟ3− and δ18O-NO3− values ranged from +4.4 ‰ to +20.3 ‰ and from −0.5 ‰ to +14.4 ‰, respectively. The application of a Bayesian model showed that the proportional contribution of organic pollution from industries, animal breeding facilities and manure fertilizers exceeded 70 % in most river sites with an overall uncertainty of ∼0.3 (UI90 index). The δ18O-NO3− and its relationship with δ18O-H2O revealed N-cycling and mixing processes, which were difficult to identify apart from the uptake of nutrients by phytoplankton during the growing season and metabolic activities. The strong correlation of δ15Ν-ΝΟ3− values with a Land Use Index (LUI) and a Point Source Index (PSI) highlighted not only the role of non-point nitrate sources but also of point sources of nitrate pollution on water quality degradation, which are usually overlooked. The nitrification of organic wastes is the dominant nitrate source in most rivers in Europe. The systematic monitoring of rivers for nitrate isotopes will help improve the understanding of N-cycling and the impact of these pollutants on ecosystems and better inform policies for protection measures so to achieve good ecological status.

Failure to control conventional cardiovascular risk factors in women with type 2 diabetes might explain worse mortality.

The standardised mortality rate (SMR) for people with diabetes in England is 1.5-1.7, with differences in outcomes between sexes. There has been little work examining the factors that could have an impact on this or on what may determine sex differences in outcome. Data were extracted for patients with type 2 diabetes (T2D) in Salford (England) in 2010 for the years up to 2020, including any deaths recorded. Expected deaths were calculated from annual Office of National Statistics mortality rate and life expectancy by age and gender, adjusted for the local Index of Multiple Deprivation (IMD). This provided the SMR deprivation (SMRd), and life expectancy years lost per death (LEYLD). The effects of treatment type, and clinical features on SMRd relative to sex were examined by univariable and multivariable analysis. Data from n=11,806 (F=5184; M=6622) patients were included. Of these, n=5540 were newly diagnosed and n=3921 died (F=1841; M=2080). In total, n=78,930 patient years. The expected deaths numbered n=2596 (adjusted for age, sex, and IMD). Excess deaths were n=1325 (F=689; M=636). Life expectancy years lost (LEYL) 18,989 (F=9714; M=9275). SMRd 1.51 (F=1.60; M=1.44) and LEYLD 4.84years (F=5.28; M=4.46). The impact of risk factors was not different by sex. However, women had higher prevalence of % diagnosed >65years of age; % last eGFR <60mLs/min/1.73m2 , and lower prevalence of % prescribed ACE-inhibitor/ARB, DPP4-inhibitor and SGLT2-inhibitor. Applying the male prevalence rate to the female population and expected mortality suggested n=437 (55%) of excess T2D female deaths were attributed to sex difference in the prevalence of these risk and protective factors. Outcomes in women with T2DM are worse than in men, contributed to by greater prevalence of adverse factors and less prescribing of cardioprotective medication.

Mechanical hierarchy in the formation and modulation of cortical folding patterns

The important mechanical parameters and their hierarchy in the growth and folding of the human brain have not been thoroughly understood. In this study, we developed a multiscale mechanical model to investigate how the interplay between initial geometrical undulations, differential tangential growth in the cortical plate, and axonal connectivity form and regulate the folding patterns of the human brain in a hierarchical order. To do so, different growth scenarios with bilayer spherical models that features initial undulations on the cortex and uniform or heterogeneous distribution of axonal fibers in the white matter were developed, statistically analyzed, and validated by the imaging observations. The results showed that the differential tangential growth is the inducer of cortical folding, and in a hierarchal order, high-amplitude initial undulations on the surface and axonal fibers in the substrate regulate the folding patterns and determine the location of gyri and sulci. The locations with dense axonal fibers after folding settle in gyri rather than sulci. The statistical results also indicated that there is a strong correlation between the location of positive (outward) and negative (inward) initial undulations and the locations of gyri and sulci after folding, respectively. In addition, the locations of 3-hinge gyral folds are strongly correlated with the initial positive undulations and locations of dense axonal fibers. As another finding, it was revealed that there is a correlation between the density of axonal fibers and local gyrification index, which has been observed in imaging studies but not yet fundamentally explained. This study is the first step in understanding the linkage between abnormal gyrification (surface morphology) and disruption in connectivity that has been observed in some brain disorders such as Autism Spectrum Disorder. Moreover, the findings of the study directly contribute to the concept of the regularity and variability of folding patterns in individual human brains.

New findings on ligand series used as SARS-CoV-2 virus inhibitors within the frameworks of molecular docking, molecular quantum similarity and chemical reactivity indices

Background: The severe acute respiratory syndrome coronavirus (SARS-CoV)-2 virus causes an infectious illness named coronavirus disease 2019 (COVID-19). SARS-CoV is a positive-sense single-stranded RNA virus from the Betacoronavirus genus. The SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) has an important role in the viral life cycle and its active site is a very accessible region, thus a potential therapeutic approach may be to target this region to study the inhibition of viral replication. Various preexisting drugs have been proposed for the treatment of COVID-19 and the use of existing antiviral agents may reduce the time and cost of new drug discoveries, but the efficacy of these drugs is limited. Therefore, the aim of the present study was to evaluate a number of ligands used as SARS-CoV-2 virus inhibitors to determine the suitability of them for potential COVID-19 treatment. Methods: In this study, we selected a series of ligands used as SARS-CoV-2 virus inhibitors such as: abacavir, acyclovir, amprenavir, ascorbic acid vitamin C, azithromycin, baloxavir, boceprevir, cholecalciferol vitamin D, cidofovir, edoxudine, emtricitabine, hydroxychloroquine and remdesivir. These ligands were analyzed using molecular docking, molecular quantum similarity, and chemical reactivity indices defined within a conceptual density functional theory framework. Results: The analysis of molecular quantum similarity indices on inhibitors showed a high number of differences from a structural point of view. However, they are quite similar in their electronic density, obtaining the highest values in the electronic similarity index. Global and local chemical reactivity indices were analyzed. Conclusions: These studies allowed for the identification of the main stabilizing interactions using the crystal structure of SARS-CoV-2 RdRp. The molecular quantum similarity and chemical reactivity descriptors provide novel insights into these ligands that can be used in the design of new COVID-19 treatments.

Perception of biodiversity in the Pisloy community, Jipijapa, Manabí, Ecuador

Biodiversity, which is essential for the provision of ecosystem services, is in decline. However, knowledge about how biodiversity is perceived and appreciated is scarce. This gap is addressed using priority species for conservation in the Pisloy community, Jipijapa, Manabí, Ecuador. The interviews with the experts (N = 56) allowed us to calculate the Local Conservation Priorities Index (IPCL). The collaborators (N = 152) contributed knowledge, attitudes, responsibility and community participation. A total of 45 species were registered, belonging to the biological groups of Birds (25 species), Liliopsida (13) and Insects (8) priority for their conservation. The collaborators only recognized 40%. The species with the highest conservation priority were the Aves Brotogeris pyrrhoptera, Chaetocercus berlepschi, Pachyramphus spodiurus and Pseudastur occidentalis, followed by the Brassia jipijapensis, Encyclia angustiloba and Oncidium estradae. Insects obtained the lowest IPCL. To conserve the species, it is proposed to carry out training for the local population, the creation of protection areas and continue with the activity of community tourism. This information is necessary to improve the relationships between biodiversity and the management of biodiversity within natural ecosystems.

Thyroid Cancer Incidence and Mortality by Socioeconomic Level in the State of São Paulo, Brazil 2001-2017

ObjectiveThyroid cancer is rising largely due to greater detection of indolent or slow-growing tumors; we sought to compare the incidence and mortality profiles of thyroid cancer in the State of São Paulo by socioeconomic status (SES). MethodsData on thyroid cancer cases diagnosed from 2003 to 2017 in the Barretos Region and from 2001 to 2015 in the municipality of São Paulo were obtained from the respective cancer registries. Corresponding death data were obtained from a Brazilian public government database. Age-standardized rates were calculated and presented as thematic maps. The rates were also calculated by SES and spatial autocorrelation was assessed by global and local indices. ResultsThere were 419 cases of thyroid cancer and 21 deaths in Barretos, contrasting with the highly populated São Paulo, with 30 489 cases and 673 deaths. The overall incidence rates in São Paulo (15.9) were three times higher than in Barretos (5.7), while incidence rates in women were close to five times higher in Barretos and four times higher in São Paulo than in men. Mortality rates were, in relative terms, very low in both regions. A clear stepwise gradient of increasing thyroid cancer incidence with increasing SES was observed in São Paulo, with rates in very high SES districts four times those of low SES (31.6 vs 8.1). In contrast, the incidence rates in Barretos presented little variation across SES levels. ConclusionThyroid cancer incidence varied markedly by SES in São Paulo, with incidence rates rising with increasing socioeconomic index. Overdiagnosis is likely to account for a large proportion of the thyroid cancer burden in the capital.

Color Doppler Ultrasound Assessment of Subclinical Activity With Scoring of Morphea.

Detection of activity in morphea is paramount for adequately managing the disease. Subclinical ultrasound involvement on inactive lesions or healthy skin areas adjacent to morphea has not been described to date. The study aimed to detect morphea's subclinical activity by Color Doppler ultrasound not identified with the clinical scorings. This cross-sectional retrospective study was done from January 2014 to July 2019 in patients with a clinicopathological diagnosis of morphea. The modified Localized Scleroderma Skin Severity Index (mLoSSI) and The Ultrasound Morphea Activity Score (US-MAS) were used to correlate clinical and subclinical activity. A total of 36 patients met the inclusion criteria. 54% of cases presented subclinical activity in areas adjacent to the clinically active lesion, 23% in nonadjacent regions, and 23% demonstrated activity at a clinically inactive lesion site.100% of patients with morphea "en coup de sabre" involving the frontal region of the face concomitantly presented both subclinical activities of morphea on the frontal facial region and the scalp following the same axis.A positive relationship was observed between the degree of clinical activity measured by mLoSSI and US-MAS scoring.The main limitations of our study were the low number of patients and the inability to detect alterations < 0.1 mm. Subclinical activity is frequent in morphea, can extend beyond the lesional areas, including apparently noninvolved adjacent and distant corporal regions, and can be detected by color Doppler ultrasound.

Analyzing the cosmic web environment in the vicinity of grand-design and flocculent spirals with local geometric index

We explore the environment of a combined set of 367 grand-design and 619 flocculent spiral galaxies. We introduce a novel estimator called the local geometric index to quantify the morphology of the local environment of these 986 spirals. The local geometric index allows us to classify the environment of galaxies into voids, sheets, filaments, and clusters. We find that grand-designs are mostly located in dense environments like clusters and filaments (∼ 78%), whereas the fraction of the flocculents lying in sparse environments like voids and sheets is significantly higher (> 10%) than that of the grand-designs. A p-value < 10-3 from a Kolmogorov-Smirnov test indicates that our results are statistically significant at 99.9% confidence level. Further, we note that dense environments with large tidal flows are dominated by the grand-designs. On the other hand, low-density environments such as sheets and voids favor the growth of flocculents.

Diffuse and Localized Functional Dysconnectivity in Schizophrenia: a Bootstrapped Top-Down Approach

Schizophrenia is a brain disorder leading to detached mind’s normally integrated processes. Hence, the exploration of the symptoms in relation to functional connectivity (FC) had great relevance in the field. Connectivity can be investigated on different levels, going from global features to single edges between pairs of regions, revealing diffuse and localized dysconnection patterns. In this context, schizophrenia is characterized by a different global integration with reduced connectivity in specific areas of the brain, part of the Default Mode Network (DMN). However, the assessment of FC presents various sources of uncertainty. This study proposes a multi-level approach for more robust group-comparison. FC data between 74 AAL brain areas of 15 healthy controls (HC) and 12 subjects with chronic schizophrenia (SZ) were used. Multi-level analyses were carried out by the previously published SPIDER-NET tool. Graph topological indexes were evaluated to assess global abnormalities. Robustness was augmented by bootstrapped (BOOT) data and the stability was evaluated by removing one (RST1) or two subjects (RST2). The DMN subgraph was extracted and specifically evaluated. Changes relevant to the overall local indexes were also analyzed. Finally, the connection weights were explored to enhance common strongest activations/deactivations. At a global level, expected trends of the indexes were found and the significance of modularity (p = 0.043) was not confirmed by BOOT (p = 0.133). The robustness assessment tests (both RST1 and RST2) highlighted more stable results for BOOT compared to the direct data testing. Conversely, significant results were found in the analysis at lower levels. The DMN highlighted reduced connectivity and strength as well as increased deactivation in the SZ group. At local level, 13 areas were found to be significantly different (p &lt; 0.05) in the groups, highlighting a greater divergence in the frontal lobe. These results were confirmed analyzing the single negative edges, suggesting inverted connectivity between prefronto-temporal areas. In conclusion, multi-level analysis supported by BOOT is highly recommended when analyzing FC, especially when diffuse and localized dysconnections must be investigated in limited samples.

Influence of the co- and counter-swirl on combustion instability of the centrally staged combustor

The centrally staged combustor is an effective way to reduce NOx emissions from combustors. However, combustion instability caused by the mutual coupling between flames and acoustics during the combustion process is almost unavoidable. To better understand this problem, the effect of the swirl rotational direction is investigated in this paper using two different schemes with co-swirl and counter-swirl configurations. Pressure fluctuations and flame dynamics are investigated under self-excited combustion oscillation conditions. The CH* chemiluminescence distribution captured by a high-speed camera is utilized to characterize the flame macrostructure and heat release fluctuations. Furthermore, non-oscillating reaction velocity fields are acquired using particle image velocimetry (PIV) technology. The results indicate that the amplitude and frequency of the counter-swirl scheme are higher than those of the co-swirl scheme at varying main stage equivalence ratios. Combining the results from dynamic mode decomposition and the local Rayleigh index, it is found that the heat release regions of the counter-swirl scheme are mainly concentrated in the shear layer. Higher velocity gradients, vorticities, and strain rates in the inner shear layer (ISL) and outer shear layer (OSL) for the counter-swirl scheme are verified using PIV technology. The driving sources of thermoacoustic oscillations are located in the regions of the ISL, OSL, and the area where the flame impinges on the sidewall of the liner. Additionally, the counter-swirl scheme exhibits larger vorticities and strain rates in the ISL and OSL, facilitating the development of thermoacoustic oscillations.

Dependence of the Annual Asymmetry Local Index for the NmF2 Median on Solar Activity

Dependence of the Annual Asymmetry Local Index for the NmF2 Median on Solar Activity

Cortical signature of depressive symptoms in frontotemporal dementia: A surface-based analysis.

Depressive symptoms are frequently reported in patients affected by frontotemporal dementia (FTD). At structural MRI, cortical features of depressed FTD patients have been poorly described. Our objective was to investigate correlations between cortical measures and depression severity in FTD patients. Data were obtained from the Frontotemporal Lobar Degeneration Neuroimaging Initiative (FTLDNI) database. We included 98 controls and 92 FTD patients, n = 38 behavioral variant FTD (bvFTD), n = 26 non-fluent variant Primary Progressive Aphasia (nfvPPA), and n = 28 semantic variant Primary Progressive Aphasia (svPPA). Patients underwent clinical and cognitive evaluations, as well as a 3D T1-weighted MRI on a 3 Tesla scanner (Siemens, Trio Tim system). Depression was evaluated by means of Geriatric Depression Scale (GDS). Surface-based analysis was performed on T1-weighted images to evaluate cortical thickness, a measure of gray matter integrity, and local gyrification index (lGI), a quantitative metric of cortical folding. Patients affected by svPPA were more depressed than controls at NPI and depression severity at GDS was higher in svPPA and bvFTD. Severity of depression correlated with a decrease in lGI in left precentral and superior frontal gyrus, supramarginal and postcentral gyrus and right precentral, supramarginal, superior parietal and superior frontal gyri. Furthermore, depression severity correlated positively with cortical thickness in the left medial orbitofrontal cortex. We found that lGI was associated with depressive symptoms over brain regions involved in the pathophysiology of major depressive disorder. This finding provides novel insights into the mechanisms underlying psychiatric symptoms in FTD.

The mental health impact of the COVID-19 pandemic on post-secondary students: A longitudinal study

This prospective longitudinal study measured sex-specific changes in depression, anxiety, and stress scores using, validated Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and the Perceived Stress Scale (PSS) in a cohort of 1445 post-secondary students (500 males, 945 females) assessed at three time points from December 2020 to January 2022. Participants were ascertained from a population of 15,585 students with in-person activities on campus at baseline and recruited from December 2020 to January 2021. We also assessed how sociodemographic characteristics influenced students' mental health outcomes. Inverse probability weighting was used to account for missing data and attrition. Linear mixed effects models were used to analyze the relationship between the mental health scores in each questionnaire, demographic and academic data, and public health stringency measured by the local stringency index. No change was observed in questionnaire scores over time for males and females, but the stringency index was significantly associated with increased stress. Being in a non-health-related-field or being white affected males and females differently for stress and anxiety, but not depression. Demographics tended to be more influential on females’ mental health than males. In conclusion, mental health resource allocation in time of emerging pandemic could benefit from targeted interventions.