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Conduct disorder is a psychological condition marked by persistent patterns of rule-breaking, aggression and disregard for societal norms. As pornography consumption becomes increasingly prevalent among young adults, concerns have emerged regarding its potential psychological and social implications. This study explores how pornography consumption may contribute to conduct disorder symptoms among young adults through an in-depth qualitative analysis. Using a case-study approach, four individuals with a history of frequent pornography consumption and behavioural issues linked to conduct disorder were selected. Data were collected through detailed interviews, focusing on their experiences, behavioural patterns and psychological effects. The analysis revealed that prolonged exposure to certain types of pornography was associated with increased impulsivity, aggression and rule-breaking tendencies. Participants also reported social and emotional challenges, further reinforcing conduct disorder symptoms. This study suggests that specific patterns of pornography consumption may play a role in the development or worsening of conduct disorder symptoms. Recognizing these behavioural links is crucial for creating effective prevention and intervention strategies, especially for young adults at risk of engaging in deviant or criminal behaviour.
Background: The consistency of effects of lemborexant (LEM), a dual orexin-receptor antagonist, on sleep maintenance variables across 2 phase 3 studies with contrasting populations was compared. Methods: E2006-G000-304 (Study 304; NCT02783729) and E2006-J086-311 (Study 311; NCT04549168) were 1-month, randomized, double-blind, placebo (PBO)-controlled studies evaluating LEM 10mg (LEM10) in adults with insomnia disorder. Global Study 304 (N=1006; PBO, n=208; LEM10, n=269) enrolled participants of any race (≥55y); Study 311 (N=193; PBO, n=100; LEM10, n=93) participants were exclusively Chinese (≥18y). Pairs of polysomnograms were conducted at baseline and after the first/last 2 doses of the 1-month treatment. Change from baseline in sleep efficiency (SE [%]), wake-after-sleep-onset (WASO [min]), and total-sleep-time (TST [min]) were analyzed. Results: Mean baseline sleep parameters: Study 304: SE, 67.9–68.9; WASO, 111.8–114.8; TST, 325.1–330.7; Study 311: SE, 69.4–70.3; WASO, 79.3-–85.8; TST, 333.2–336.7. Least squares mean [standard error] increases from baseline were significantly larger with LEM10 vs PBO (P<0.001) for SE (Study 304, 8.0 [0.7]; Study 311, 7.1 [1.4]) and TST (38.9 [3.7]; 32.8 [6.9]), as were decreases in WASO (-25.4 [3.1]; -17.8 [4.8]). Most treatment-emergent adverse events were mild–moderate. Conclusions: Short-term LEM10 treatment consistently improved objective sleep maintenance in patients with insomnia of different races.
The Indian Pulsar Timing Array (InPTA) employs unique features of the upgraded Giant Metrewave Radio Telescope (uGMRT) to monitor dozens of the International Pulsar Timing Array (IPTA) millisecond pulsars (MSPs), simultaneously in the 300-500 MHz and the 1260-1460 MHz bands. This dual-band approach ensures that any frequency-dependent delays are accurately characterized, significantly improving the timing precision for pulsar observations, which is crucial for pulsar timing arrays. We present details of InPTA’s second data release that involves 7 yrs of data on 27 IPTA MSPs. This includes sub-banded Times of Arrival (ToAs), Dispersion Measures (DM), and initial timing ephemerides for our MSPs. A part of this dataset, originally released in InPTA’s first data release, is being incorporated into IPTA’s third data release which is expected to detect and characterize nanohertz gravitational waves in the coming years. The entire dataset is reprocessed in this second data release providing some of the highest precision DM estimates so far and interesting solar wind related DM variations in some pulsars. This is likely to characterize the noise introduced by the dynamic inter-stellar ionised medium much better than the previous release thereby increasing sensitivity to any future gravitational wave search.
Background: COMISA (comorbid insomnia and obstructive sleep apnea) is associated with daytime functioning and cognitive impairments. This post hoc analysis assessed the impact of lemborexant (LEM), a dual-orexin-receptor-antagonist approved to treat insomnia in adults, on morning sleepiness/alertness in participants with COMISA. Methods: Of the overall population (n=1006), 410 (40.8%) adults (≥55 years) with comorbid insomnia disorder and mild obstructive sleep apnea (apnea-hypopnea-index, 5–≤15 events/h) from Study E2006-G000-304 (NCT02783729), a 1-month, randomized, placebo- and active-controlled study, were analyzed. Participants received placebo (PBO), LEM 5mg (LEM5), LEM 10mg (LEM10), or zolpidem tartrate 6.25mg (not reported). A daily sleep diary assessed morning sleepiness/alertness (1, extremely sleepy to 9, extremely alert). Participants (%) shifting from baseline mild/moderate sleepiness (≤3) towards greater alertness (4, 5, or >5) during the first/last 7 mornings of the study were analyzed. Results: At baseline, 17/75 (22.7%), 36/112 (32.1%), and 28/104 (26.9%) participants with COMISA receiving PBO, LEM5, or LEM10, respectively, reported mild/moderate sleepiness. Across the first/last 7 mornings, more participants shifted from mild/moderate sleepiness towards alertness with LEM5 (66.7%, 82.9%) and LEM10 (64.3%, 75.0%) versus PBO (47.1%, 64.7%), respectively. Conclusions: A greater percentage of participants with COMISA experienced improvements in morning sleepiness across the treatment period with LEM versus PBO.
Background: Ischemic stroke often results in long-term motor impairments due to disrupted corticospinal pathways. Transcranial magnetic stimulation (TMS) motor mapping is a non-invasive technique used to assess corticospinal integrity by measuring motor evoked potentials (MEPs). This study investigates whether MEP amplitudes can predict impairment severity and functional performance in chronic stroke. Methods: Four non-human primates (NHPs) with chronic stroke (> six months) following transient right middle cerebral artery occlusion underwent TMS motor mapping using neuronavigation under ketamine anesthesia. Single pulses of TMS (50-70% of maximum stimulator output) were applied to the affected and contralesional primary motor cortices to elicit MEPs and assess cortical excitability. Intramuscular electromyography recorded muscle responses from the biceps, extensor digitorum longus, and abductor pollicis brevis. Neurological dysfunction was evaluated daily for three weeks using the NHP Stroke Scale, NHP Upper Extremity Motor Dysfunction Scale, and the primate Rankin Scale. Results: MEPs were present in NHP1, NHP3, and NHP4 but absent in NHP2. Stronger MEPs correlated with lower impairment severity and better functional performance, while NHP2 exhibited higher impairment and poorer performance. Conclusions: MEP presence and strength can serve as biomarkers of motor recovery potential, highlighting their role in assessing corticospinal integrity and functional outcomes.
Background: We aim to assess the resting state functional connectivity (RSFC) and reactivity with functional near-infrared spectroscopy (fNIRS) in patients with acute stroke compared to age, sex and comorbidity-matched subjects. Methods: Patients with acute anterior circulation stroke syndrome localizing to the right (RH) or left hemisphere (LH) were enrolled. RSFC was assessed using group-level seed-based (Primary Motor cortex,PMC) correlation analysis. Finger-tapping-associated relative oxygen Hemoglobin (ΔHbO) changes were analyzed with generalized linear model regression. Results: 127 participants (RH stroke, 51; LH stroke, 43; control, 33) enrolled at a median of 21 (15,29) hours after symptom onset. Compared to the control group, the RSFC with the affected PMC (LH stroke) was reduced over the affected somatosensory cortex (SSC) in the minor ischemic stroke (IS) (r = -0.14 (-0.3,-0.01)), minor intracerebral hemorrhage (ICH) (-0.48 (-0.78,-0.18)) and major ICH groups (-0.2 (-0.4,-0.01). In the FT task compared to the control groups in LH stroke, ΔHbO was increased over the affected SSC in minor IS (β11.2(1.9,20.5)) and major ICH group (β11.7 (1.4,22.1)). In the FT task in RH stroke, ΔHbO was increased over the unaffected PMC in minor IS (β12.1(2.3,21.8)), major IS (β14.9 (0.3,29.5)), minor ICH (β25.7 (10.1,41.2)) and major ICH (β13.4 (1.1,25.6). Conclusions: Motor cortex dysconnectivity may be worse over the LH stroke. In RH stroke, there is early compensatory increased neuronal activity over the unaffected PMC. These results suggest differential acute remodelling in RH and LH strokes.
Background: Plasma pTau217 is a robust biomarker for the diagnosis of Alzheimer’s disease (AD). However, most pTau217 assays are not widely available for clinical testing. We assessed the performance of two commercially available plasma pTau217 immunoassays in a clinical diagnostic laboratory for AD diagnosis. Methods: 219 plasma samples from healthy controls with negative amyloid PET, 115 plasma samples from pathology-confirmed and 263 samples with confirmed amyloid PET were selected. Plasma pTau217 levels were measured using the ALZpath pTau217 assay on the Quanterix HD-X Simoa platform and the Lumipulse pTau217 assay on the Lumipulse G1200 platform at and BC Neuroimmunology Lab and Neurocode USA. Results: For the ALZpath assay, the coefficients were 10.4%, 10.4%, and 9.9%, and for the Fujirebio assay, were 12.1%, 12.2%, and 5.3%, respectively. Sample stability and interference were similar between the two assays, although moderate heterophilic antibody interference and reduced frozen sample stability at -20˚C were observed for the Fujirebio assay. Both assays demonstrated similar clinical performance and differentiated individuals with AD (ALZpath AUC = 0.94; Fujirebio AUC = 0.90). Conclusions: The performance of the two pTau 217 assays was comparable. The clinical separation between the healthy controls and those with Amyloid pathology was nearly complete for both assays.
The two-spined deepwater cardinalfish, Epigonus bispinosus Okamoto & Gon 2018 is documented for the first time from the Arabian Sea (n= 2) (137.4–151.1 mm SL). The specimens were caught by a demersal shrimp trawl operated along the Kerala coast at a depth of 250–420 m. This species was previously recorded in South Africa and northern Madagascar regions. The present study also provides the first molecular information on E. bispinosus based on mitochondrial cytochrome oxidase subunit I and 16S ribosomal RNA genes. Detailed taxonomic identification, and molecular and phylogenetic analysis are described.
Cortical excitability has been proposed as a novel neurophysiological marker of neurodegeneration in Alzheimer’s dementia (AD). However, the link between cortical excitability and structural changes in AD is not well understood.
Objective:
To assess the relationship between cortical excitability and motor cortex thickness in AD.
Methods:
In 62 participants with AD (38 females, mean ± SD age = 74.6 ± 8.0) and 47 healthy control (HC) individuals (26 females, mean ± SD age = 71.0 ± 7.9), transcranial magnetic stimulation resting motor threshold (rMT) was determined, and T1-weighted MRI scans were obtained. Skull-to-cortex distance was obtained manually for each participant using MNI coordinates of the motor cortex (x = −40, y = −20, z = 52).
Results:
The mean skull-to-cortex distances did not differ significantly between participants with AD (22.9 ± 4.3 mm) and HC (21.7 ± 4.3 mm). Participants with AD had lower motor cortex thickness than healthy individuals (t(92) = −4.4, p = <0.001) and lower rMT (i.e., higher excitability) than HC (t(107) = −2.0, p = 0.045). In the combined sample, rMT was correlated positively with motor cortex thickness (r = 0.2, df = 92, p = 0.036); however, this association did not remain significant after controlling for age, sex and diagnosis.
Conclusions:
Patients with AD have decreased cortical thickness in the motor cortex and higher motor cortex excitability. This suggests that cortical excitability may be a marker of neurodegeneration in AD.
The application of a tube combustion system (pyrolyzer) for the batch combustion of low carbon content environmental matrices, such as soil and sediment, for determining 14C specific activity is examined. The samples were combusted at 600°C, and the CO2 species produced were trapped in 3N NaOH, precipitated as BaCO3 by adding BaCl2, and subjected to acid-hydrolysis to transfer the CO2 species to the absorber-scintillator mixture for liquid scintillation counting (LSC). The method was validated by analyzing the samples by accelerator mass spectrometry (AMS) method. The minimum detectable activity (MDA) for the method, at 2σ confidence level, was 10 Bq kg–1C (4 pMC) for a counting time of 500 min and 7 Bq kg–1C (3 pMC) for 1000 min. The capability of the method to quantify a small excess of 14C specific activity (a few Bq kg–1C or pMC) in the environment of a nuclear facility, when compared to the ambient natural background level, was demonstrated by analyzing a total of 23 soil and 7 sediment samples from the vicinity of a pressurized heavy water reactor (PHWR) nuclear power plant (NPP) at Kaiga, India. The maximum excess 14C specific activity values recorded for soil and sediment matrices were 37 ± 7 Bq kg–1C and 11 ± 7 Bq kg–1C, respectively, confirming minimal radioecological impact of the operation of the NPP on the environment. The 14C specific activity ratio for the recently fallen leaf litter and the soil underneath at most of the sampling points in the vicinity of the NPP had a mean value of 1.03 with an associated standard deviation of 0.07. Statistical tests confirm that the mean values of the data set of 14C specific activity of leaf litter and underlying soil are not significantly different.
Electromyogram (EMG)-controlled prosthetic hands have advanced significantly during the past two decades. However, most of the currently available prosthetic hands fail to replicate human hand functionality and controllability. To measure the emulation of the human hand by a prosthetic hand, it is important to evaluate the functional characteristics. Moreover, incorporating feedback from end users during clinical testing is crucial for the precise assessment of a prosthetic hand. The work reported in this manuscript unfolds the functional characteristics of an EMG-CoNtrolled PRosthetIC Hand called ENRICH. ENRICH is a real-time EMG controlled prosthetic hand that can grasp objects in 250.8$ \pm $1.1 ms, fulfilling the neuromuscular constraint of a human hand. ENRICH is evaluated in comparison to 26 laboratory prototypes and 10 commercial variants of prosthetic hands. The hand was evaluated in terms of size, weight, operation time, weight lifting capacity, finger joint range of motion, control strategy, degrees of freedom, grasp force, and clinical testing. The box and block test and pick and place test showed ENRICH’s functionality and controllability. The functional evaluation reveals that ENRICH has the potential to restore functionality to hand amputees, improving their quality of life.
Norm-based accounts of social behavior in economics typically reflect tradeoffs between maximization of own consumption utility and conformity to social norms. Theories of norm-following tend to assume that there exists a single, stable, commonly known injunctive social norm for a given choice setting and that each person has a stable propensity to follow social norms. We collect panel data on 1468 participants aged 11–15 years in Belfast, Northern Ireland and Bogotá, Colombia in which we measure norms for the dictator game and norm-following propensity twice at 10 weeks apart. We test these basic assumptions and find that norm-following propensity is stable, on average, but reported norms show evidence of change. We find that individual-level variation in reported norms between people and within people across time has interpretable structure using a series of latent transition analyses (LTA) which extend latent class models to a panel setting. The best fitting model includes five latent classes corresponding to five sets of normative beliefs that can be interpreted in terms of what respondents view as “appropriate” (e.g. equality vs. generosity) and how they view deviations (e.g. deontological vs. consequentialist). We also show that a major predictor of changing latent classes over time comes from dissimilarity to others in one’s network. Our application of LTA demonstrates how researchers can engage with heterogeneity in normative perceptions by identifying latent classes of beliefs and deepening understanding of the extent to which norms are shared, stable, and can be predicted to change. Finally, we contribute to the nascent experimental literature on the economic behavior of children and adolescents.
The therapeutic effects of soya consumption on adipokine concentrations have yielded inconsistent results in previous meta-analyses. This umbrella meta-analysis aims to investigate the impact of soya and its isoflavones on serum adiponectin and leptin levels in adults. We searched the Cochrane Central, Web of Science, PubMed and Scopus databases until October 10, 2024. The articles were restricted to those written in English. We included meta-analysis studies that evaluated the effects of soya and its isoflavones on levels of adiponectin and leptin and reported effect sizes (ES) and corresponding CI. Two independent reviewers screened all articles based on eligibility criteria and extracted the required data from the included meta-analyses. The meta-analysis was performed using a random-effects model in STATA software. Six meta-analyses of randomised controlled trials meeting the inclusion criteria were included in the current umbrella meta-analysis. The findings indicated that soya and its isoflavones did not have a significant effect on adiponectin (ES = 0·10; 95 % CI: −0·22, 0·41; P = 0·55; I2 = 51·8 %) and leptin (ES = −0·37; 95 % CI: −1·35, 0·61; P = 0·46; I2 = 71·2 %) concentrations. Subgroup analysis based on participants’ mean age, total sample size and duration was conducted. Results showed that the effect is not statistically significant in any of the subgroups. In conclusion, soya and its isoflavones could not improve the adipokines mentioned above. However, further high-quality research in different countries is required to substantiate these findings.
With wide-field phased array feed technology, the Australian Square Kilometre Array Pathfinder (ASKAP) is ideally suited to search for seemingly rare radio transient sources that are difficult to discover previous-generation narrow-field telescopes. The Commensal Real-time ASKAP Fast Transient (CRAFT) Survey Science Project has developed instrumentation to continuously search for fast radio transients (duration $\lesssim$ 1 s) with ASKAP, with a particular focus on finding and localising fast radio bursts (FRBs). Since 2018, the CRAFT survey has been searching for FRBs and other fast transients by incoherently adding the intensities received by individual ASKAP antennas, and then correcting for the impact of frequency dispersion on these short-duration signals in the resultant incoherent sum (ICS) in real time. This low-latency detection enables the triggering of voltage buffers, which facilitates the localisation of the transient source and the study of spectro-polarimetric properties at high time resolution. Here we report the sample of 43 FRBs discovered in this CRAFT/ICS survey to date. This includes 22 FRBs that had not previously been reported: 16 FRBs localised by ASKAP to $\lesssim 1$ arcsec and 6 FRBs localised to $\sim 10$ arcmin. Of the new arcsecond-localised FRBs, we have identified and characterised host galaxies (and measured redshifts) for 11. The median of all 30 measured host redshifts from the survey to date is $z=0.23$. We summarise results from the searches, in particular those contributing to our understanding of the burst progenitors and emission mechanisms, and on the use of bursts as probes of intervening media. We conclude by foreshadowing future FRB surveys with ASKAP using a coherent detection system that is currently being commissioned. This will increase the burst detection rate by a factor of approximately ten and also the distance to which ASKAP can localise FRBs.
Due to different timing of drug launches across countries, published health technology assessment (HTA) findings from one country may impact HTA outcomes in other countries. The aim of our work was to identify the most influential HTA bodies by analyzing to what extent HTA bodies cross-reference each other in their HTA reports.
Methods
We analyzed the HTA reports on single drug assessments (SDA) published by 46 HTA bodies from 28 countries (and cross-country collaborations) with decision dates between January 2011 and November 2023. We searched the identified HTA reports by using natural language processing and a predefined set of keywords to identify whether, and to what extent, HTA bodies reference each other in their HTA reports. Additionally, we assessed if there is a trend over time in the cross-referencing, and whether any clusters could be identified.
Results
Based on the analysis of 24,793 SDAs, the National Institute for Health and Care Excellence (NICE) was referenced the most (in 4,198 HTA reports across 39 HTA bodies), followed by the Canadian Agency for Drugs and Technologies in Health (in 2,034 reports across 35 HTA bodies), and the Scottish Medicines Consortium (SMC) (in 1,960 reports across 31 HTA bodies). The HTA bodies that most often referenced other HTAs were the Agency for Health Technology Assessment and Tariff System, the Haute Autorité de santé, and NICE. Seven HTA bodies were not referenced in any HTA report, while four did not reference any other HTA body.
Conclusions
Our research shows that most of the analyzed HTA agencies not only referenced other HTA bodies in their HTA reports but were also referenced by other HTA bodies. The most often referenced HTA agencies were mostly from English-speaking countries, were well recognized, and had well defined methodologies.
Residual blood specimens collected at health facilities may be a source of samples for serosurveys of adults, a population often neglected in community-based serosurveys. Anonymized residual blood specimens were collected from individuals 15 – 49 years of age attending two sub-district hospitals in Palghar District, Maharashtra, from November 2018 to March 2019. Specimens also were collected from women 15 – 49 years of age enrolled in a cross-sectional, community-based serosurvey representative at the district level that was conducted 2 – 7 months after the residual specimen collection. Specimens were tested for IgG antibodies to measles and rubella viruses. Measles and rubella seroprevalence estimates using facility-based specimens were 99% and 92%, respectively, with men having significantly lower rubella seropositivity than women. Age-specific measles and rubella seroprevalence estimates were similar between the two specimen sources. Although measles seropositivity was slightly higher among adults attending the facilities, both facility and community measles seroprevalence estimates were 95% or higher. The similarity in measles and rubella seroprevalence estimates between the community-based and facility serosurveys highlights the potential value of residual specimens to approximate community seroprevalence.
Tuberculosis (TB) is one of the deadliest infectious diseases globally, ranking as 13th leading cause of mortality and morbidity. According to the Global Tuberculosis Report 2022, TB claimed the lives of 1.6 million people worldwide in 2021. Among the casualties, 1 870 000 individuals with HIV co-infections contributed to 6.7% of the total fatalities, accounting TB as the second most lethal infectious disease following COVID-19. In the quest to identify biomarkers for disease progression and anti-TB therapy, microRNAs (miRNAs) have gained attention due to their precise regulatory role in gene expression in disease stages and their ability to distinguish latent and active TB, enabling the development of early TB prognostic signatures. miRNAs are stable in biological fluids and therefore will be useful for non-invasive and broad sample collection. However, their inherent lack of specificity and experimental variations may lead to false-positive outcomes. These limitations can be overcome by integrating standard protocols with machine learning, presenting a novel tool for TB diagnostics and therapeutics. This review summarizes, discusses and highlights the potential of miRNAs as a biomarker, particularly their differential expression at disease stages. The review assesses the advantages and obstacles associated with miRNA-based diagnostic biomarkers in pulmonary TB and facilitates rapid, point-of-care testing.
Electromyogram (EMG) has been a fundamental approach for prosthetic hand control. However it is limited by the functionality of residual muscles and muscle fatigue. Currently, exploring temporal shifts in brain networks and accurately classifying noninvasive electroencephalogram (EEG) for prosthetic hand control remains challenging. In this manuscript, it is hypothesized that the coordinated and synchronized temporal patterns within the brain network, termed as brain synergy, contain valuable information to decode hand movements. 32-channel EEGs were acquired from 10 healthy participants during hand grasp and open. Synergistic spatial distribution pattern and power spectra of brain activity were investigated using independent component analysis of EEG. Out of 32 EEG channels, 15 channels spanning the frontal, central and parietal regions were strategically selected based on the synergy of spatial distribution pattern and power spectrum of independent components. Time-domain and synergistic features were extracted from the selected 15 EEG channels. These features were employed to train a Bayesian optimizer-based support vector machine (SVM). The optimized SVM classifier could achieve an average testing accuracy of 94.39 $ \pm $ .84% using synergistic features. The paired t-test showed that synergistic features yielded significantly higher area under curve values (p < .05) compared to time-domain features in classifying hand movements. The output of the classifier was employed for the control of the prosthetic hand. This synergistic approach for analyzing temporal activities in motor control and control of prosthetic hands have potential contributions to future research. It addresses the limitations of EMG-based approaches and emphasizes the effectiveness of synergy-based control for prostheses.
Objectives: Patients with mild cognitive impairment (MCI) employ compensatory cognitive processes to maintain independence in day-to-day functioning as compared to patients with Alzheimer’s dementia (AD). The dorsolateral prefrontal cortex (DLFPC) supports cognitive compensation in normal aging and MCI. Using Paired Associative Stimulation combined with Electroencephalography (PAS-EEG) we have previously shown that patients with AD have impaired DLPFC plasticity compared to healthy control (HC) individuals. The aim of this study is to examine whether DLPFC plasticity in individuals with MCI is preserved compared to those with AD and HC, serving as a potential mechanism underlying cognitive compensation in MCI.
Methods: We analyzed a combined cross-sectional data of 47 AD, 16 MCI, and 40 HC participants from three different studies that assessed their DLPFC plasticity using PAS-EEG. PAS-EEG assesses DLPFC plasticity via the induction of Long Term Potentiation (LTP)-like activity, thereby referred to as PAS-LTP. Using multiple regression, we compared PAS-LTP in MCI to PAS-LTP in AD and HCs, after adjusting for age andgender.
Results: Among the 47 participants with AD (mean [SD] age = 75.3 [7] years), 29 were women and 18 were men; among the 16 participants with MCI (mean [SD] age = 74.8 [6] years), 11 were women and 5 were men; and among the 40 HCs (mean [SD] age = 76.4 [5.1] years), 22 were women and 18 were men. After adjusting for age and gender, there was an impact of diagnostic group on PAS-LTP [F (2,95) = 4.19, p = 0.018, between-group comparison η2 = 0.81]. Post-hoc comparisons showed that participants with MCI had a higher PAS-LTP (mean [SD] = 1.31 [0.49]) than those with AD (mean [SD] = 1.09 [0.28]) (Bonferroni corrected p = 0.042) but not different from PAS-LTP in HCs (mean [SD] = 1.25 [0.33]) (Bonferroni corrected p = 1.0).
Conclusions: Our findings indicate that plasticity is preserved in the DLPFC among individuals with MCI, supporting the hypothesis that DLPFC plasticity contributes to cognitive compensation towards delaying progression to AD. Thus, further enhancement of longer preservation of DLPFC plasticity in individuals with MCI could further delay the onset of AD in this population.
Transmission electron microscopy-energy dispersive X-ray analysis (TEM-EDX) represents an effective tool for determining the stoichiometric composition of clay minerals, but the methodology is often hampered by analytical difficulties. Studies of beam-sensitive minerals, such as smectites, are associated with low count intensities and dynamic loss of cations (e.g. K+, Na+, and Al3+), which can lead to erroneous quantifications of composition. After exploring how to minimize cation migration by reducing the beam current density to <5 pA cm–2, the most reliable and consistent compositions were determined using 1 μm2 area measurements of particles acquired in normal TEM mode where the electron beam was parallel, the degree of specimen damage was at its minimum and good acquisition intensities (>10,000 cps) were acquired. Based on 528 TEM-EDX area analyses, the composition of Wyoming montmorillonites (SWy-1, SWy-2, and SWy-3) was studied in their natural and Ca-saturated states from thin (<50 nm thick) particle aggregates lying on lacey carbon films. Overall, the TEM-EDX results confirmed the heterogeneous charge distributions of montmorillonite at the particle and sample levels. The average composition per formula unit of SWy-1 to -3 was determined as: (Na0.12Ca0.04Mg0.03K0.02)(Si3.91Al0.09)(Al1.57Mg0.27Fe0.19)2.03 O10(OH)2 · nH2O, where the tetrahedral and octahedral layer charges are –0.09 and –0.19 per O10(OH)2, respectively, and the total layer charge ranges from –0.25 to –0.30 per O10(OH)2 (mean of –0.28). This study demonstrates how TEM-EDX can provide new insight into the natural heterogeneities of smectite chemistry as long as adequate calibration and specimen damage control procedures are implemented.