Human Variation Research Articles

Shock Patients and Enteral Nutrition?

Shock is a life-threatening condition characterized by microcirculatory disturbances and inadequate tissue perfusion. In hemodynamically unstable individuals, arterial pressure is maintained with vasoactive agents. Enteral nutrition (EN) is crucial for the intensive treatment of critically ill patients, facilitating intestinal recovery and improving clinical outcomes such as reducing infections, shortening hospital stays, and lowering costs. The impact of vasoactive agents on gastrointestinal blood flow varies, depending on the drug, dose, body size, and individual sensitivity. EN is categorized into early and delayed, and multiple guidelines recommend delayed EN due to the risks in the early stage, which may lead to EFI, non-obstructive mesenteric ischemia and necrosis. Guidelines for early EN in shock patients are still evolving, exploring the optimal timing and safety thresholds. Studies have shown that early EN can be safely implemented in hemodynamically stable patients maintaining a mean arterial pressure of 70 mmHg with stable doses of antihypertensives. This review summarizes the optimal and safe timing of initiating EN in shock patients to guide clinical practice. The pathophysiology of shock, EN selection, considerations, nutritional regimens, effects of antihypertensive agents, and feeding regimens are further discussed.

Short-term repeated oral intake of low dose cannabidiol: effects on liver enzyme activity and creatinine concentration during intense exercise.

The side effects and safety of cannabidiol (CBD) products are currently discussed in different contexts. Of all adverse effects, hepatotoxic effects have been reported most frequently in previous studies. However, the threshold for liver toxicity of CBD in humans is uncertain due to the lack of adequately designed studies in humans below the lowest observed adverse effect level (LOAEL) of 300 mg/day. In a randomised, three-arm, double-blind, crossover study, the effects of two CBD products (oil and solubilisate (solu) containing 60 mg CBD) were investigated during a high-intensity exercise protocol. Seventeen well-trained subjects (26±4 years, 181±5 cm, 85.6±9.4 kg) participated in the intervention. All subjects were healthy and had no physiological or psychological injuries. Participants were divided into advanced (Ad) and highly advanced (Hi) athletes … They consumed 60 mg of the compound in each microcycle over 7 days. To evaluate possible effects of short-term repeated use of 60 mg CBD on oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), gamma-glutamyl transferase (GGT) and creatinine (CREA) were analysed before and after each microcycle. GOT increased significantly in both performance levels of the placebo groups (Ad: p≤0.001; Hi: p=0.003). This increase was significantly reduced in the Ad group by both CBD oil (p=0.050, ES=0.66) and CBD solu (p=0.027; ES=0.75). GPT also increased significantly in both placebo groups (Ad: p≤0.001; Hi: p=0.032). This increase was significantly reduced in the Ad group by both CBD oil (p=0.027; ES=0.75) and CBD solu (p=0.023; ES=0.77). These effects were not observed in the Hi group for either parameter. Our results show that short-term repeated use of 60 mg CBD can inhibit exercise-induced liver activity. Furthermore, under the conditions of the present study, there was no evidence for hepatotoxic effects of oral intake of CBD at 60 mg for seven days. Nevertheless, despite the inhibitory effect on exercise-induced liver activity, the study provides evidence for the pharmacological effects of CBD on the liver even at low CBD dose and does not exclude adverse effects in sensitive individuals.

Opposite effects of isometric exercise on pain sensitivity of healthy individuals: the role of pain modulation.

Exercise-induced hypoalgesia (EIHypo) among healthy individuals is well documented; however, the opposite effect of exercise, ie, exercise-induced hyperalgesia (EIHyper), has mainly been described in patients with chronic pain or after intense/painful exercise. We investigated the extent to which EIHypo and/or EIHyper occur among healthy participants and whether these responses are associated with individuals' pain modulation capacity. Fifty-seven participants (mean age 29.20 ± 5.21 years) underwent testing of pressure pain threshold as an index of EIHypo/EIHyper: pain adaptation, offset analgesia (OA), and conditioned pain modulation as indices of pain modulation, prior to and immediately postsubmaximal isometric exercise (n = 40) or rest (n = 17, control group). Body awareness and exercise-evoked stress were also evaluated. Test-retest repeatability of the pain modulation indices was performed as well. Twenty-four participants (60%) exhibited EIHypo, whereas 16 (40%) exhibited EIHyper. Pressure pain threshold did not change in the control group. Baseline (preexercise) OA efficacy predicted EIHypo/EIHyper. Furthermore, OA significantly decreased postexercise in the EIHyper subgroup and slightly increased in the EIHypo subgroup. Exercise-induced hypoalgesia was associated with magnitude of daily exercise while EIHyper was associated with increased exercise-evoked stress and body awareness. Submaximal isometric exercise can induce opposite effects on pain sensitivity among healthy participants-EIHypo or EIHyper. Descending pain inhibition pathways, and top-down influences over these pathways, seem to be involved in EIHypo/EIHyper effects. As such isometric exercise is often preferred in early stages of rehabilitation, preliminary screening individuals' vulnerability to this exercise is important; OA test may be used for this purpose.

Sensitivity of Septoria lycopersici Speg. isolates to fungicides in Brazil

Disease management using synthetic fungicides is the main strategy used by tomato growers to prevent tomato yield reductions caused by Septoria leaf spot (SLS). Despite the importance of this plant disease, there is little information about the sensitivity of Septoria lycopersici isolates to fungicides. The sensitivity of 94 isolates of S. lycopersici to azoxystrobin, chlorothalonil, tebuconazole, and thiophanate-methyl was assessed in experiments using fungicide-amended 96-well microtiter plates. The highest EC 50 values above 100 mg/L were detected for azoxystrobin, thiophanate-methyl, and tebuconazole. Based on these results, five isolates classified as resistant and five as sensitive to each fungicide were selected for the experiments. Tomato plants were inoculated with sensitive (S) and resistant (R) isolates and sprayed by the fungicides in three greenhouse assays. The differences in the values of the area under the progress curve of Septoria leaf spot (AUDPC), disease severity progress, and progress rates were not so pronounced between tomato plants sprayed and non-sprayed with fungicides. The AUDPC values for plants inoculated with S and R isolates and treated with chlorothalonil, tebuconazole, and thiophanate-methyl ranged from 10 to 320, 0 to 80, and 50 to 150, respectively. For azoxystrobin, the AUDPC values were around 200 in plants inoculated with S and R isolates. There is evidence of reduced sensitivity of individuals of S. lycopersici to azoxystrobin, tebuconazole, and thiophanate-methyl in the population in Brazil. Therefore, tomato growers should rotate and combine fungicides with different mechanisms of action and low-risk of resistance to control SLS.

Can Thinning Foster Forest Genetic Adaptation to Drought? A Demo-Genetic Modelling Approach With Disturbance Regimes.

In managed populations-whether for production or conservation-management practices can interfere with natural eco-evolutionary processes, providing opportunities to mitigate immediate impacts of disturbances or enhance selection on tolerance traits. Here, we used a modelling approach to explore the interplay and feedback loops among drought regimes, natural selection and tree thinning in naturally regenerated monospecific forests. We conducted a simulation experiment spanning three nonoverlapping generations with the individual-based demo-genetic model Luberon2. Luberon2 integrates forest dynamics processes driving survival and mating success, including tree growth, competition, drought impacts and regeneration, with genetic variation in quantitative traits related to these processes. We focused on two variable traits: individual vigour, determining diameter growth potential without stress as the deviation from average stand growth, and individual sensitivity to drought stress as the slope of the relationship between diameter growth and drought stress level. We simulated simplified thinning scenarios, tailored to even-aged stands. Considering plausible genetic variation and contrasting drought regimes, the predicted evolutionary rates for both traits aligned with documented rates in wild plant and animal populations. Thinning considerably reduced natural selective pressures caused by competition and drought compared to unthinned stands. However, the conventional thinning practice of retaining the larger trees resulted in indirect anthropogenic selection that enhanced genetic gain in vigour and lowered sensitivity by up to 30%. More intensive thinning aimed at reducing drought stress by reducing stand density hampered the selection against sensitivity to drought, potentially hindering long-term adaptation. Conversely, avoiding the early, nonselective thinning step-thereby promoting both natural and anthropogenic selection-ultimately resulted in better stand performance while maintaining long-term evolvability. This study emphasises the potential of evolution-oriented forestry strategies to combine drought stress mitigation with genetic adaptation. It provides general insights into how population management, disturbance regimes and eco-evolutionary responses interfere, aiding sustainable decision-making amid environmental uncertainties.

Variants of physiological FDG vascular activity on digital PET.

Fluorodeoxyglucose PET/computed tomography (FDG PET/CT) is effective in detecting large vessel vasculitis. Digital PET cameras have improved spatial resolution compared with analog PET, resulting in more prominent physiological uptake in arterial walls. This study's goal was to define qualitative normal variants of arterial activity on digital PET/CT. We retrospectively reviewed 126 oncological PET/CT studies. Exclusion criteria included history of vasculitis, immunosuppressant therapy, hyperglycemia, or altered FDG biodistribution. Qualitative vessel wall activity (common carotid, brachiocephalic, subclavian, aorta, and femoral) was visually graded by two nuclear physicians with guideline-proposed criteria: 0: ≤mediastinum, 1: <liver, 2: = liver, 3: >liver, where grade 3 is compatible, 2 is possible, and <2 is negative for vasculitis. Cranial artery uptake was visually graded as follows: grade 0: ≤surrounding tissues, grade 1: just above surrounding tissues, and grade 2: significantly above surrounding tissues, with grades 1 and 2 considered positive for cranial artery vasculitis. Large vessel uptake was grade 3 in 0 subjects, grade 2 in four subjects (3%), grade 1 in 87 subjects (69%), and grade 0 in 35 subjects (28%). In studies acquired ≥75 min post-injection, 1/15 subjects had grade 2 uptake. Four subjects (3%) had grade 1 vertebral artery uptake. No subjects had temporal, maxillary, or occipital artery uptake. A minority of our subjects presented with grade 2 large vessel uptake, which was associated with longer uptake times, or grade 1 cranial artery uptake, which was associated with higher age and glycemia. These findings should be interpreted with caution in patients referred for suspected vasculitis, as they may represent normal variants on digital PET.

A Systematic Review and Meta-Analysis on Contrast Sensitivity in Schizophrenia.

Understanding perceptual alterations in mental disorders can help uncover neural and computational anomalies. In schizophrenia, perceptual alterations have been reported for many visual features, including a deficit in contrast sensitivity, a key measure of visual function. The evidence supporting this deficit, however, has not been comprehensively synthesized. We conducted a systematic review and meta-analysis of studies measuring contrast sensitivity in individuals with schizophrenia and healthy controls. Our search identified 46 studies, of which 43 focused on chronic patients. We found that patients with chronic schizophrenia have reduced contrast sensitivity (g = 0.74; 95% CI, 0.55 to 0.93; P = 8.2 × 10-10). However, we found evidence that the deficit could be driven by medication. Additionally, none of the studies estimated attentional lapses, leaving it uncertain whether a potentially higher frequency of lapses in patients contributes to the observed deficit. Furthermore, only two studies comprehensively assessed visual acuity, complicating the understanding of the role of spatial frequency in the observed deficit. While we identified a robust deficit in contrast sensitivity among chronic schizophrenia patients, the influence of attentional lapses and medication on this impairment remains unclear. We make several suggestions for future research to clarify the underlying mechanisms contributing to this deficit.

Disrupted sense of agency-related ownership and disownership increase in the Rubber Hand Illusion

Empirical evidence suggests that body ownership and the sense of agency operate as an interactive system correlated with the level of consciousness during tasks involving modifications in body representation. This study sought to elucidate the nature of this association by documenting the verbal manifestations of this interaction. Specifically, the study aimed to reveal the role of a sense of agency in the individual sensitivity to the Rubber Hand Illusion (RHI). The sense of agency was measured through a post hoc interview wherein participants could verbally express their rubber hand ownership and real hand disownership experiences following the RHI examination. The RHI was induced in 49 healthy, right-handed college volunteers, including 28 males (mean age 28.6) and 21 females (mean age 26.6). Three main scores - ownership, disownership, and proprioceptive drift - were defined to measure individual sensitivity to Rubber Hand Illusion. Verbal reports related to the RHI were analyzed utilizing an automated narrative content analysis toolkit which explored the deeper content of words and stories to identify situation-driven cognitive processes, specifically focusing on the rate of sense of agency and other cognitive variables. The findings indicated that a greater disruption in the sense of agency predicts increased sensitivity to the Rubber Hand Illusion. Therefore, individuals with a lower rate sense of agency exhibit increased malleability in body representation when a rubber hand illusion is induced.

FATS inhibits the Wnt pathway and induces apoptosis through degradation of MYH9 and enhances sensitivity to paclitaxel in breast cancer

Breast cancer is one of the most prevalent and diverse malignancies, and, with global cases increasing, the need for biomarkers to inform individual sensitivity to chemotherapeutics has never been greater. Our retrospective clinical analysis predicted that the expression of the fragile site-associated tumor suppressor (FATS) gene was associated with the sensitivity of breast cancer to neoadjuvant chemotherapy with paclitaxel. In vitro experiments subsequently demonstrated that FATS significantly increased the inhibitory effects of paclitaxel on breast cancer cells’ migration, growth, and survival. An interaction screen revealed that FATS interacted with MYH9 and promoted its degradation via the ubiquitin-proteasome pathway, thereby downregulating Wnt signaling. By overexpressing FATS and MYH9, we demonstrated that FATS enhanced paclitaxel-induced apoptosis in breast cancer cells by degrading MYH9 to downregulate the Wnt pathway. We also demonstrated in a mouse xenograft model that FATS significantly increased the chemosensitivity of breast cancer cells to paclitaxel in vivo. This study presents a new mechanism by which FATS interacts with MYH9 to suppress the Wnt/β-catenin signaling pathway and induce apoptosis, thus enhancing the sensitivity of breast cancer cells to paclitaxel chemotherapy. The results also propose novel biomarkers for predicting breast cancer sensitivity to neoadjuvant chemotherapy with paclitaxel. Finally, we provide in vivo evidence that the combination of paclitaxel with IWR-1, a novel Wnt pathway inhibitor, synergistically suppresses breast cancer growth, laying the foundation for future trials with this drug combination. These results therefore provide a number of potential solutions for more precise treatment of patients with breast cancer in the future.

Carbon pricing and the commodity risk premium

This paper examines whether the carbon pricing risk factor is priced in the cross-section of commodity futures. By analyzing unexpected pricing shocks in carbon emission allowances, carbon pricing risk is indeed priced in commodity futures, with a significant positive risk premium. The analysis of carbon pricing risk loadings reveals that individual commodities' sensitivities to carbon pricing risk vary. Additionally, commodity-specific characteristics, such as basis and hedging pressure, impact these risk loadings. Finally, I demonstrate that a portfolio of commodity futures constructed based on carbon pricing beta provides superior out-of-sample hedging performance for climate change risk compared to alternative hedge portfolios using equities or ETFs.

Individual color matches and cone spectral sensitivities in 100 observers of varying age

Individual color matches and cone spectral sensitivities in 100 observers of varying age

Analysis of allergen positivity rates in relation to gender, age, and cross-reactivity patterns

Objective: This study aims to gain a deeper understanding of the patterns of allergen detection positivity rates among different age and gender groups, and to explore cross-reactivity patterns among allergens. Methods: We conducted a retrospective analysis of patients who underwent allergen testing at our hospital. The sample for this study included all patients who underwent allergen testing. We utilized immune blotting to detect specific IgE antibodies to 20 allergens in patient sera. Results: The study results showed a higher proportion of female samples (72.35%) compared to male samples (27.65%). Among all participants, the age distribution was primarily concentrated in the 25–35 age group, accounting for 37.43% of the total sample, followed by the 45 years and older age group, accounting for 27.00%. This indicates that allergic symptoms may occur not only in children and adolescents but also at any time after adulthood. We further observed significant influences of factors such as gender and age on individual sensitivity to specific allergens. For example, compared to males, females were found to be more sensitive to certain allergens such as cat hair, dust mites, and dog epithelium. Similarly, we also found variations in sensitivity to specific allergens among different age groups. Conclusion: Close monitoring of allergen distribution in populations facilitates active engagement of allergic individuals in self-management, while gender and age may be important factors influencing individual sensitivity to specific allergens. These findings provide valuable insights for understanding the pathogenesis of allergic diseases and designing more effective prevention and treatment strategies.

Disorders of puberty

Puberty is a critical developmental phase marking the transition from childhood to adulthood, characterised by physical, hormonal and psychological changes. Disorders of puberty can have a significant impact on a person’s growth, development, and psychological well-being. These disorders can cause precocious (early onset) or delayed (late onset) puberty and necessitate a thorough understanding of the underlying mechanisms and clinical presentation to ensure proper diagnosis and treatment. This article provides a comprehensive overview of the hypothalamic–pituitary–gonadal axis and adrenal development leading to physical changes consistent with puberty. This article outlines the physiological physical changes and pubertal milestones and discusses normal variants of puberty to help distinguish physiological from pathological conditions. It then describes the pathophysiology and causes for both precocious and delayed pubertal development, providing guidance for primary care physicians for referral to secondary care. Finally, this article aims to provide succinct guidance on relevant history and clinical findings pertinent to the topic and provides a clinical case for discussion.

The interplay among environmental sensitivity, job stressors, and leadership styles on employee well-being

Investigating the role of individual differences in Environmental Sensitivity for well-being and stress at work is an emerging area of research with significant potential for practical implications in organizational management and human resources. Recent studies have begun to explore how individuals with high sensory-processing sensitivity (SPS) may be more vulnerable to work-related stress than their less sensitive peers, but may also derive greater benefits from positive job resources when available. The present study aims to investigate the role of leadership style in the complex interplay between individual differences in sensitivity, stress at work, and general well-being. A questionnaire was administered through Qualtrics to a total of 317 workers from two medium–large–sized Italian companies, across two waves between May and July 2022. Findings provided support for a three-way interaction effect, with job stressors exerting an adverse effect on participants’ well-being, mitigated by democratic and let-it-be leadership styles at the team level, particularly among highly sensitive individuals. Thus, our findings suggest a vantage sensitivity effect and underscore the importance of cultivating positive work climates to enhance workers’ ability to cope with stressors and improve their global well-being, with particular relevance for highly sensitive individuals.

The vague language use scale: Clinical utility and psychometrics from adults with traumatic brain injury.

Pragmatic communication difficulties encompass many distinct behaviours, including the use of vague and/or insufficient language, a common characteristic following traumatic brain injury (TBI) that negatively impacts psychosocial outcomes. Existing assessments evaluate pragmatic communication broadly, often with only one or two items capturing each behaviour, thus limiting sensitivity and precision to variations within each behaviour. Given that greater nuance is needed to detect subtle pragmatic communication differences and investigate underlying cognitive mechanisms, a more refined measure is critical to improve psychosocial outcomes. The Vague scale was developed to address those needs. To provide preliminary evidence supporting the novel Vague language use (Vague) scale's reliability, validity and clinical utility. The Vague scale rates each discourse sample utterance for vague language use on a 3-point scale; the measure's Vague score represents the mean of utterance-level ratings. Using the Vague scale, two raters naïve to diagnosis evaluated Cinderella narratives of 46 adults with severe TBI and 46 controls with no brain injury, providing reliability, construct validity and classification accuracy evidence. Vague scores were also compared to other clinical measures to gather criterion-related validity evidence. Interrater agreement across all transcripts was moderate. Construct validity was supported by expected group differences and criterion validation, including significant relationships with increased violations of Grice's maxim of quantity and measures of lexical variation; significant relationships with psychosocial outcomes, supporting clinical utility; and nonsignificant relationships with measures of syntax and overall pragmatic communication. Classification accuracy expectedly did not support using Vague scores in isolation for diagnosis, due to unacceptable sensitivity (0.696). Evidence supported the Vague scores' psychometric properties. Thus, the Vague scale shows promise as a measure of one distinct pragmatic communication behaviour: vague language use. Future research should apply the Vague scale to determine its sensitivity in individuals with subtle social communication challenges (e.g., mild TBI), explore its utility with more naturalistic discourse samples as part of a pragmatic communication battery, longitudinally examine changes in Vague scores, and investigate cognitive mechanisms underlying this specific pragmatic communication behaviour. What is already known on this subject Use of vague language is common following traumatic brain injury (TBI) and may contribute to negative psychosocial outcomes related to employment and relationships. However, existing measures of vague language lack sensitivity and precision, limiting their utility for identifying subtle performance variations or determining the cognitive mechanisms underlying this specific pragmatic communication behaviour. What this study adds to existing knowledge The current study gathered promising reliability, validity and clinical utility evidence to support using the novel Vague language use (Vague) scale, which was developed to address these limitations. Based on complex (Cinderella) stories of adults with and without TBI, Vague scores demonstrated moderate interrater agreement and promising construct validity based on expected group differences and criterion validation, including moderate associations with related constructs and weak associations with unrelated constructs. Because pragmatic communication profiles post-TBI can vary, classification accuracy expectedly indicated that Vague scores should not be used alone to identify communication differences post-TBI. What are the clinical implications of this work? Vague scores show promise for documenting clients' use of vague language and planning intervention to address associated discourse-level challenges. Future research should investigate applying the Vague scale to naturalistic discourse samples (1) as part of a battery that sensitively and precisely identifies pragmatic communication differences and (2) as a tool for investigating cognitive mechanisms underlying vague language use, with the goal of improving interventions that support pragmatic communication and enhance psychosocial outcomes.

Harnessing Herbal Ingredients in Hair Cosmetics: A Natural Approach to Hair Care

Hair plays a crucial role in the human body and it is imperative to uphold a healthy scalp. Various factors, including hormonal influences, age, gender, pollution, and food habits impact the hair. Herbal ingredients such as amla, hibiscus, brahmi, neem, saw palmetto etc are widely used to treat hair disorders such as premature hair loss, dandruff, and canities. Herbal ingredients may be used in hair shampoos, oils, tonics, serums, gels, conditioners etc. This article offers a detailed examination of the utilisation of natural components in hair care products, emphasising their importance and advantages in supporting scalp health, encouraging hair growth, and improving overall hair condition. It also reviews the sensory aspect and potential aromatherapy of herbal hair treatments. The article addresses the challenges and considerations related to herbal formulations, such as individual sensitivities, shelf life, and the need for transparency in labelling.

Exploring the correlation between airborne pollen levels and respiratory conditions in Jaipur, India

ABSTRACT Airborne pollen, a significant natural pollutant, restricts outdoor activities and impacts quality of life for sensitive individuals with pulmonary disorders. This study examines trends in airborne pollen concentrations and explores whether air pollution, pollen concentration, or both impact patient counts. The annual pollen trend in Jaipur shows peaks in pollen concentration in March (due to trees, 66%), September (due to weeds, 45%), and December (due to grass, 50%). Among the fifteen taxa examined, Holoptelea integrifolia is the largest pollen emitter in Jaipur, followed by Poaceae, among others. The count of patients arriving for clinical consultations in a hospital shows a strong and positive correlation with weed (Asteraceae spp. and Argemone mexicana) and grass pollen. A linear regression equation is developed (R2 value = 0.835) for forecasting consulting patient counts based on Cassia siamea pollen concentration. This can assist hospital administration in resource management, especially during peak allergy seasons.

Anatomical Approach for the Evaluation of the Nipple-Areolar Complex.

The nipple-areolar complex (NAC) is an anatomically unique region from which several normal variants and pathologies arise. Understanding its anatomy is crucial for accurate clinical and imaging assessments, aiding with differential diagnosis, and ensuring radiologic-pathologic concordance. Mammography and US are commonly used for NAC evaluation; however, these are susceptible to technical limitations such as tissue superimposition and artifacts, compromising visualization of abnormalities in this area. Although MRI offers higher sensitivity, it is not the initial evaluation modality. A comprehensive clinical inspection is necessary because it may reveal abnormalities not apparent on imaging. This article offers an anatomical approach to the NAC evaluation, simplifying differential diagnoses by reviewing imaging techniques and clinical features of common NAC abnormalities.

A novel cortical biomarker signature predicts individual pain sensitivity.

Biomarkers would greatly assist decision making in the diagnosis, prevention and treatment of chronic pain. The present study aimed to undertake analytical validation of a sensorimotor cortical biomarker signature for pain consisting of two measures: sensorimotor peak alpha frequency (PAF) and corticomotor excitability (CME). In this cohort study (recruitment period: November 2020-October 2022), participants experienced a model of prolonged temporomandibular pain with outcomes collected over 30 days. Electroencephalography (EEG) to assess PAF and transcranial magnetic stimulation (TMS) to assess CME were recorded on Days 0, 2 and 5. Pain was assessed twice daily from Days 1-30. Data collection occurred at a single centre: Neuroscience Research Australia. We enrolled 159 healthy participants (through notices placed online and at universities across Australia), aged 18-44 with no history of chronic pain, neurological or psychiatric condition. 150 participants completed the protocol. Participants received an injection of nerve growth factor (NGF) to the right masseter muscle on Days 0 and 2 to induce prolonged temporomandibular pain lasting up to 4 weeks. We determined the predictive accuracy of the PAF/CME biomarker signature using a nested control-test scheme: machine learning models were run on a training set (n = 100), where PAF and CME were predictors and pain sensitivity was the outcome. The winning classifier was assessed on a test set (n = 50) comparing the predicted pain labels against the true labels. The final sample consisted of 66 females and 84 males with a mean age of 25.1 ± 6.2. The winning classifier was logistic regression, with an outstanding area under the curve (AUC=1.00). The locked model assessed on the test set had excellent performance (AUC=0.88[0.78-0.99]). Results were reproduced across a range of methodological parameters. Moreover, inclusion of sex and pain catastrophizing as covariates did not improve model performance, suggesting the model including biomarkers only was more robust. PAF and CME biomarkers showed good-excellent test-retest reliability. This study provides evidence for a sensorimotor cortical biomarker signature for pain sensitivity. The combination of accuracy, reproducibility, and reliability, suggests the PAF/CME biomarker signature has substantial potential for clinical translation, including predicting the transition from acute to chronic pain. Question: Can individuals be accurately classified as high or low pain sensitive based on two features of cortical activity: sensorimotor peak alpha frequency (PAF) and corticomotor excitability (CME)?Findings: In a cohort study of 150 healthy participants, the performance of a logistic regression model was outstanding in a training set (n=100) and excellent in a test set (n=50), with the combination of slower PAF and CME depression predicting higher pain. Results were reproduced across a range of methodological parameters.Meaning: A novel cortical biomarker can accurately distinguish high and low pain sensitive individuals, and may predict the transition from acute to chronic pain.

Ventricular Arrhythmia Classification Using Similarity Maps and Hierarchical Multi-Stream Deep Learning.

Ventricular arrhythmias are the primary arrhythmias that cause sudden cardiac death. We address the problem of classification between ventricular tachycardia (VT), ventricular fibrillation (VF) and non-ventricular rhythms (NVR). To address the challenging problem of the discrimination between VT and VF, we develop similarity maps - a novel set of features designed to capture regularity within an ECG trace. These similarity maps are combined with features extracted through learnable Parzen band-pass filters and derivative features to discriminate between VT, VF, and NVR. To combine the benefits of these different features, we propose a hierarchical multi-stream ResNet34 architecture. Our empirical results demonstrate that the similarity maps significantly improve the accuracy of distinguishing between VT and VF. Overall, the proposed approach achieves an average class sensitivity of 89.68%, and individual class sensitivities of 81.46% for VT, 89.29% for VF, and 98.28% for NVR. The proposed method achieves a high accuracy of ventricular arrhythmia detection and classification. Correct detection and classification of ventricular fibrillation and ventricular tachycardia are essential for effective intervention and for the development of new therapies and translational medicine.