Current Behavior Research Articles

WAVE SPECTRUM ANALYSIS FOR OPERATIONAL OFFSHORE PLATFORM IN MALAYSIA WATER

As an ageing platform has passed its design life of 20 to 30 years, it is crucial to identify wether it is still fit for operation based on the current environmental behaviour, particularly due to the wave impact. Hence, an analytical approach of wave spectrum analysis between the wave behaviour and offshore structural response will be conducted. The aim is to verify the stability and safety of ageing offshore platforms with the current wave behaviour based on identifying wave characteristics, developing a normalized wave energy spectral density, and analyzing the natural frequency of offshore structural response. The methodology includes data collection from structural dynamic monitoring assessments, wave spectrum development using empirical models, and evaluation of offshore platform stability. The results will provide insights into platform stability, resonance risks, and safety assessment of ageing offshore platforms in Malaysian waters. The findings will contribute to recommendations for modifications or improvements to ensure the safety and integrity of offshore platforms in the specific region.

A new fault detection and relay coordination technique for low voltage DC microgrid

Integration of various distributed generation units in the DC distribution network creates an outsized impact on magnitude and direction of fault current. The specific behaviour of fault current during a short circuit fault demands quick and reliable detection and isolation of fault, which poses a significant challenge in developing an effective protection and coordination scheme for DC microgrids. In this regard, a new fault detection and relay coordination algorithm is proposed for a Low voltage DC (LVDC) microgrid, which utilizes inverse time relay characteristics based on variance of fault current. While the relay responds and picks up during both internal and external faults, its operation is automatically limited upon operation of the downstream circuit breaker without the need for any communication channel. The efficacy of the proposed strategy is evaluated by modelling a mesh-connected DC microgrid network using PSCAD/EMTDC software. The protection coordination problem is developed as a constraint non-linear optimization problem to determine optimal relay settings. The proposed approach has been tested by simulating various types of faults at different fault locations and fault resistances along with various microgrid operating modes. The results suggest that the proposed strategy stands out by optimizing relay operating time and providing backup protection while upholding relay coordination. A comparative assessment of the proposed technique with existing ones proves its effectiveness in terms of swift relay tripping time, better immunity against noise, and independency against microgrid operating mode and topology.

Research on interregional oil cooperation-sanctions with evolutionary game

PurposeThe game strategies differ when different regions participate in the oil game. Under what circumstances will different participants choose cooperation or sanction strategies? This is the core issue of this paper.Design/methodology/approachRegarding the current and future game behavior between different regions in the oil trade, this paper constructs an evolutionary game model between two regions to explore the possibility of sanctions strategies between the two sides in different situations.FindingsThe research finds: (1) When the benefits of in-depth cooperation between the two regions are greater, both sides tend to adopt cooperative strategies. (2) When the trade conflict losses between the two regions are smaller, both sides adopt sanctions strategies. (3) When a strong region trades with a weak region, if the former adopts a sanctions strategy, the net profits are greater than the benefits of in-depth cooperation between the two regions. If the latter adopts a sanctions strategy, the net profits are less than the trade conflict losses between the two regions. There will be the strong region adopting a sanctions strategy and the weak region adopting a non-sanctions strategy. At this time, the latter should reasonably balance the immediate and future interests and give up some current interests in exchange for in-depth cooperation between the two regions. Otherwise, it will fall into the situation of unilateral sanctions by the strong against the weak.Originality/valueThere is no paper in the existing literature that uses the evolutionary game method to analyze the oil game problem between the two regions. This paper constructs a two-party evolutionary game model composed of crude oil importers and crude oil exporters and, based on this, analyzes the evolutionary stability between the two regions under sanctions and cooperation strategies, which enriches the energy research field.

Time-lapse surveys reveal patterns and processes of erosion by exceptionally powerful turbidity currents that flush submarine canyons: A case study of the Congo Canyon

The largest canyons on Earth occur on the seafloor, and seabed sediment flows called turbidity currents play a key role in carving these submarine canyons. However, the processes by which turbidity currents erode submarine canyons are very poorly documented and understood. Here we analyse the first detailed time-lapse bathymetric surveys of a large submarine canyon, and its continuation as a less-deeply incised channel. These are also the most comprehensive time-lapse surveys before and after a major canyon-channel flushing turbidity current. These unique field data come from the Congo Submarine Fan offshore West Africa, where canyon flushing turbidity currents between 2019 and 2020 eroded ~2.65 km3 of seabed sediment, as they travelled for over 1100 km at speeds of 5–8 m/s. This eroded sediment volume is equivalent to ~19–33 % of global sediment flux from all rivers to the oceans. The time-lapse surveys cover 40 % of the 1100 km long submarine canyon-channel. They show that erosion was predominantly (94 %) along the canyon-channel axis, with only 6 % from failures along canyon or channel flanks. However, erosion along the canyon-channel floor was very patchy; some areas were eroded to depths of 10–20 m, whilst intervening areas showed no significant change. Knickpoints with up-slope migrating headscarps account for 22 % of the total eroded volume. One knickpoint in the deep-sea channel migrated by 21 km in one year, making it the fastest moving submarine knickpoint yet documented. Most (62 %) eroded sediment was in zones extending across the canyon or channel floor, without distinct headscarps as is the case for knickpoints. Erosion restricted to outer bends only comprised 10 % of the total, suggesting processes of erosion differ significantly from meandering rivers in which outer bend erosion is more important. Patchy seabed erosion appears to be mainly due to flow-bed processes (e.g. knickpoints), but spatial variations in seabed sediment properties may also play a role. The irregular seabed erosion occurs despite near-uniform flow speeds observed between moorings and submarine cable breaks with spacing of tens to hundreds of kilometers. Patchy and localised erosion has important implications for assessing hazards to seabed telecommunication cables, which are more likely to break in areas of deep erosion, and for creating appropriate numerical models of seabed erosion and turbidity current behaviour, or how to interpretate ancient submarine canyons and channels in rock outcrops.

A Cross-Sectional Survey of Healthcare Professionals' Knowledge, Attitude and Current Behaviours towards Female Fertility Preservation Services within the UK.

(1) Background: This study aims to establish the knowledge, attitudes and current behaviours towards female fertility preservation (FP) services amongst healthcare professionals (HCPs) in the UK. (2) Methods: An online survey was advertised publicly on the social media platform Instagram between 25 February 2021 and 11 March 2021. (3) Results: In total, 415 participants fulfilled the inclusion criteria and completed the survey. The majority of HCPs discussed FP techniques either never 39.5% (n = 164), once a year 20.7% (n = 86) or once a month 17.8% (n = 74). The majority rated their knowledge of each type of FP method as 'very poor' or 'poor' and strongly disagreed 14.2% (n = 59) or disagreed 42.2% (n = 175) with the statement they 'felt confident to counsel a patient on FP'. The majority either agreed 37.8% (n = 157) or strongly agreed 22.2% (n = 92) that it was their responsibility to discuss FP and 38.1% (n = 158) agreed or strongly agreed 19.5% (n = 81) they considered the desire for future fertility when planning treatment. The majority 87.2% (n = 362) had not experienced formal training on FP. (4) Conclusions: Discrepancies in knowledge remain regarding techniques of FP, referral pathways, awareness of facilities offering services and existing educational resources. Many HCPs recognise the importance of FP and their responsibility to initiate discussions. The knowledge that FP may not delay the treatment of cancer has also improved; however, training in FP is scarce.

Effect of polypyrrole incorporation amounts on the optical and electrical properties of PVA/CMC blended polymer for optoelectronic applications

In the present work, hybrid flexible blended polymers of polypyrrole (PPy)/polyvinyl alcohol (PVA)/carboxymethyl cellulose (CMC); PVA/CMC/x wt % PPy; were constructed as promising blended materials to be used in various optoelectronics applications. X-ray diffraction and scanning electron microscopy techniques were used to investigate the structure and the surface morphology of polymer nanocomposites. The doped blends have better absorption of the three types of ultraviolet (UVA, UVB, and UVC), as well as the visible spectrum. The transmittance values in the visible range dropped from 90 % to 63 % as the PPy concentration reached 0.5 wt%. At x = 0.5, the minimum direct and indirect optical band gap energy values of (4.82, 4.39, 4.23) eV and (3.76, 3.84, 3.62, 2.93) eV, respectively, were obtained. The incorporation of PPy into the PVA/CMC blend led to a regular rise in the refractive index value within the visible range. The blend doped with 0.5 wt % PPy exhibited the highest optical dielectric constant values within the visible range. The enhancement/reduction in the fluorescence intensity depended on the excitation wavelength and the amount of PPy doping in the blended polymers. The effect of voltage, temperature and the amount of PPy doping on the current behavior of the resulting electric current in all blends was explored. The ohmic and nonohmic natures and the charge transport mechanisms of different blends were determined.

Monitoring Enzymatic Reaction Kinetics and Activity Assays in Confined Nanospace.

Enzyme-mediating biotransformations commonly occur in micro- and nanospace, which is crucial to maintain the essential biochemical processes and physiological functions in living systems. Probing enzyme-catalytic reactions in a biomimetic fashion remains challenging due to the lack of competent tools and methodology. Here, we show that studying enzymatic reaction kinetics can be readily achieved by a well-designed solid-state nanopore. Using tyrosine as a classical substrate, we quantitatively characterize the catalytic activity of tyrosinase (TYR) and tyrosine decarboxylase (TDC) in a nanoconfined space. Tyrosine was first immobilized in the nanopipette, wherein the active sites of tyrosine were left unoccupied. When successively exposed to TYR and TDC, a two-step cascade reaction can spontaneously take place. In this process, the surface wettability and charge of the nanopipette stemming from the catalytic products can sensitively regulate ion transport and ionic current rectification behavior, which were monitored by ionic current signal. In this biomimetic scenario, we obtained the enzymatic reaction kinetics of monophenyl oxidase that were not previously actualized in the conventional macroenvironment. Significantly, TYR showed higher enzyme activity, with a Km value of 1.59 mM, which was lower than that measured in a free and open space (with a Km of 3.01 mM). This suggests that tyrosine should be the most appropriate substrate of TYR, thus improving our understanding of tyrosine-associated biochemical reactions. This work offers an applicable technical platform to mimic enzyme-mediated biotransformations and biometabolisms.

Schottky barrier diode and photoelectric device based on two dimensional noble transition-metal sulfides vertical heterojunction

In this work, we use first-principles method to investigate the properties of two-dimensional noble transition-metal sulfides MS2 (M = Ni, Pd, Pt) and the electronic and optoelectronic applications of their vertical heterojunctions. The vertically bilayer or trilayer stacking can modulate the band structures and optical absorption spectra of MS2 (M = Ni, Pd, Pt) obviously. Therefore, we create the atomically thin Schottky barrier diodes (SBD) by vertically stacking the MS2 (M = Ni, Pd, Pt) on monolayer MS2 (M = Ni, Pd, Pt). All SBDs reveal more excellent current rectification behavior along the armchair edge (AE) transport direction than that along the zigzag edge (ZE) transport direction. SBD based on PdS2 bilayer and monolayer heterojunction has the high current value and the significant rectification ratio (exceeding 105) along AE transport direction. The total photocurrent densities of all SBDs along the ZE transport direction are bigger than that along the AE transport direction. SBD based on PdS2 bilayer and monolayer heterojunction has the largest total photocurrent density (1208.07 μA/mm2) along the ZE transport direction. Our work provides foundations for the application of two-dimensional noble transition-metal sulfides in rectification and optoelectronics.

Carnivore space use behaviors reveal variation in responses to human land modification

BackgroundSpatial behavior, including home-ranging behaviors, habitat selection, and movement, can be extremely informative in estimating how animals respond to landscape heterogeneity. Responses in these spatial behaviors to features such as human land modification and resources can highlight a species’ spatial strategy to maximize fitness and minimize mortality. These strategies can vary on spatial, temporal, and individual scales, and the combination of behaviors on these scales can lead to very different strategies among species.MethodsHarnessing the variation present at these scales, we characterized how species may respond to stimuli in their environments ranging from broad- to fine-scale spatial responses to human modification in their environment. Using 15 bobcat-years and 31 coyote-years of GPS data from individuals inhabiting a landscape encompassing a range of human land modification, we evaluated the complexity of both species’ responses to human modification on the landscape through their home range size, habitat selection, and functional response behaviors, accounting for annual, seasonal, and diel variation.ResultsBobcats and coyotes used different strategies in response to human modification in their home ranges, with bobcats broadly expanding their home range with increases in human modification and displaying temporal consistency in functional response in habitat selection across both season and time of day. Meanwhile, coyotes did not expand their home ranges with increased human modification, but instead demonstrated fine-scale responses to human modification with habitat selection strategies that sometimes varied by time of day and season, paired with functional responses in selection behaviors.ConclusionsThese differences in response to habitat, resources, and human modification between the two species highlighted the variation in spatial behaviors animals can use to exist in anthropogenic environments. Categorizing animal spatial behavior based on these spatiotemporal responses and individual variation can help in predicting how a species will respond to future change based on their current spatial behavior.

Construction of “island-bridge” microstructured conductive coating for enhanced impedance response of organohydrogel strain sensor

Flexible conductive hydrogels (CHs) have received widespread attention in the field of wearable strain sensor, electronic skin, and artificial intelligence owing to their excellent stretchability, biocompatibility, and real-time sensing performance. However, it still remains a critical challenge to design and construct the satisfactory wearable strain sensor integrated with high sensitivity, wide sensing range, and environmental stability, especially at extreme temperatures. Herein, ionic conductive polyacrylamide/sodium alginate nanocomposite organohydrogel anchored with electronic conductive “island-bridge” microstructured carbon nanotubes (CNTs) conformal coating was designed and fabricated for high-performance strain sensor, of which the existence of “island-bridge” microstructured electronic conductive layer and its special structure evolution upon external stretching can significantly enhance the alternating current impedance response behavior of the sensor, featuring with a high sensitivity of 76.54 at 600 % strain, wide sensing range (0–600 % strain), fast responsiveness (110 ms), extremely low detection limit (0.1 %), and favorable stability and reproducibility of over 3200 cycles. Meanwhile, the resultant organohydrogel strain sensor can precisely detect and differentiate complicated human activities even at the environment temperatures of −30 °C and 50 °C, opening a promising avenue for next-generation smart wearable electronics.

Reproductive Behavior of Adolescent Girls: Analysis of Risk Factors, Prospects of Prevention and Education

INTRODUCTION: Caring of reproductive health of children and adolescents in the society, especially of adolescent girls as a group most vulnerable to risks in the reproductive sphere, continues to be of high importance. The studies confirm that education and awareness about reproductive health can reduce the probability of problems occurring. The existing legal regulations emphasize the importance of providing accurate and timely information of reproductive health. AIM: Scientific justification of the strategy of forming safe reproductive behavior of adolescent girls on the basis of the peculiarities of their current reproductive behavior taking into account the opinion of specialists in the fields of education and healthcare. MATERIALS AND METHODS: To assess the peculiarities of reproductive behavior of adolescent girls, an anonymous questionnaire survey of 400 adolescent girls was conducted. To determine the expectations of the participants of the sex education process, as well as the main directions of preventive work and education, a survey of 400 parents of adolescent girls, 86 pediatricians, 34 obstetricians-gynecologists and 420 teachers was conducted. For all groups of participants, author’s questionnaires were developed. RESULTS: The reproductive behavior of adolescent girls living in the territory of the Novosibirsk region, is characterized by early start of sex life (15.90 ± 0.14 years), promiscuity (1.70 ± 1.10 partners), refusal to use effective means of contraception. Parents of adolescent girls emphasize the leading role of the family in sex education, suggesting participation of doctors and teachers in the process, but remain dissatisfied with the intensity of preventive measures. A similar problem is emphasized by specialists in the healthcare and education systems who indicate the possibility of conducting preventive work with adolescent girls remotely. In the opinion of pediatricians and obstetricians-gynecologists, providing preventive information on the reproductive health and behavior, will not only create safe reproductive behavior for modern adolescents, but is also an effective strategy of improving the system of reproductive health protection. CONCLUSION: The study identified features of the reproductive behavior of adolescent girls that characterize it as risky. The results emphasize the need for an integrated approach to assessing and maintaining the health of adolescent girls, and also focus attention on the importance of educational work in this age group. The study serves as a basis for further preventive strategies in the field of reproductive health and education.

Current Saturation Behavior in GaN Polarization Superjunction Hybrid Diode

This is the first report on the current saturation behavior observed in the forward characteristics of polarization superjunction (PSJ)‐based hybrid PiN‐Schottky GaN power diodes fabricated on Sapphire. In the current saturation region, most of the applied anode voltage is dropped across the regions immediately adjacent to the edge of the doped P‐GaN region closest to the cathode. This significant potential drop occurs within a short distance, resulting in a high electric field and depletion of electrons, causing the current saturation behavior via velocity saturation in these PSJ hybrid diodes.

Unveiling Local Current Behavior and Manipulating Grain Homogenization of Perovskite Films for Efficient Solar Cells.

Achieving high power conversion efficiency in perovskite solar cells (PSCs) heavily relies on fabricating homogeneous perovskite films. However, understanding microscopic-scale properties such as current generation and open-circuit voltage within perovskite crystals has been challenging due to difficulties in quantifying intragrain behavior. In this study, the local current intensity within state-of-the-art perovskite films mapped by conductive atomic force microscopy reveals a distinct heterogeneity, which exhibits a strong anticorrelation to the external biases. Particularly under different external bias polarities, specific regions in the current mapping show contrasting conductivity. Moreover, grains oriented differently exhibit varied surface potentials and currents, leading us to associate this local current heterogeneity with the grain orientation. It was found that the films treated with isopropanol exhibit ordered grain orientation, demonstrating minimized lattice heterogeneity, fewer microstructure defects, and reduced electronic disorder. Importantly, devices exhibiting an ordered orientation showcase elevated macroscopic optoelectronic properties and boosted device performance. These observations underscore the critical importance of fine-tuning the grain homogenization of perovskite films, offering a promising avenue for further enhancing the efficiency of PSCs.

The inclined conductive column effect: a new simple model for magnetotelluric anomalous phases

SUMMARY Magnetotelluric data are sometimes accompanied by ‘anomalous’ impedance phases ($\phi $xy and $\phi $yx) in the off-diagonal components deviating from the first (0° < $\phi $xy < 90°) or third (−180° < $\phi $yx < −90°) quadrant, especially in long-period bands. This phenomenon is called the phases out-of-quadrant (POQ). The POQ poses a challenge in magnetotelluric modelling because simple 1-D or 2-D models cannot explain it. Previous studies have reported that strong inhomogeneity, anisotropy, or particular 3-D structures, such as the L-shaped or cross-shaped conductors, could explain the POQ. Aside from these models, we have discovered that a slanted columnar conductor also generates the POQ. Our systematic investigation through the synthetic forward modelling of an inclined conductive column with a varying geometry showed that the inclination angle and the column length may affect the POQ appearance. We investigated herein the behaviour of the electric currents around the inclined conductive column embedded in a resistive half-space. We found that the induced electric field in the region with the POQ tends to point in the opposite direction to the surrounding vectors. This result can reasonably explain the inverted phase in long-period bands. Furthermore, we confirmed that current is sucked into one end of the column, but discharged from the other end, suggesting that the column works as a current channel. The localized reverse vectors are associated with the current channelling along the inclined conductor, which generates the POQ. A volcanic conduit within a resistive host rock is one of the typical field examples of such an inclined channel. Our study suggests that the POQ is a helpful clue in imaging the geometry of a volcanic magma plumbing system through magnetotelluric surveys.

Understanding Preferences for Visualized New and Future HIV Prevention Products Among Gay, Bisexual and Other Men Who Have Sex with Men in the Southern United States: A Mixed-Methods Study

ABSTRACT Men who have sex with men (MSM) are vulnerable to HIV infection. Although daily oral pre-exposure prophylaxis (PrEP) prevents HIV among MSM, its usage remains low. We conducted virtual in-depth interviews (IDIs) and focus groups (FGs) with Black, Hispanic/Latino, and White MSM consisting of current PrEP users and those aware of but not currently using PrEP. We delved into their preferences regarding six emerging PrEP products: a weekly oral pill, event-driven oral pills, anal douche/enema, anal suppository, long-acting injection, and a skin implant. Our mixed methods analysis involved inductive content analysis of transcripts for thematic identification and calculations of preferences. Among the sample (n = 98), the weekly oral pill emerged as the favored option among both PrEP Users and PrEP Aware IDI participants. Ranking exercises during FGs also corroborated this preference, with the weekly oral pill being most preferred. However, PrEP Users in FGs leaned toward the long-acting injectable. Conversely, the anal suppository and douche/enema were the least preferred products. Overall, participants were open to emerging PrEP products and valued flexibility but expressed concerns about limited protection for products designed solely for receptive sex. Public health practitioners should tailor recommendations based on individuals’ current sexual behaviors and long-term vulnerability to infection.

A Study on High School Mathematics Teaching Design Based on Teaching for Robust Understanding: Taking the Cosine Theorem as an Example

Teachers’ teaching behavior plays a crucial role in students’ development, and there are problems in the current teaching behavior of mathematics teachers such as ignoring students’ cognitive needs, lack of equal opportunities for students’ classroom performance as well as lack of formative evaluation of students. In order to solve the phenomenon, this paper analyzes and explains how to promote teaching based on the Teaching for Robust Understanding (TRU) evaluation framework with the goal of focusing on the development of all students, taking the teaching design of The Cosine Theorem as an example, and provides ideas and methods for first-line high school mathematics teachers.

Turn down for watt: Community fit and thermal comfort habituation predict average household heating energy consumption

Lowering average household heating energy consumption plays a pivotal role in addressing climate change and has been central to policy initiatives. Strategies proposed so far have included commitments, incentives/ disincentives, feedback, and social norms. Yet, findings so far have been mixed and fail to explain the mechanism that drives energy conservation behavior. Using a sample of 2,128 participants across the United States, we collected survey data matched with archival temperature data to investigate the influence of past experiences on current energy conservation behaviors. Our findings indicate that childhood home temperatures significantly predict current home temperature settings. Importantly, community fit moderated this relationship. Individuals with high community fit were more likely to align their home temperature settings to those of their community. These insights not only shed light on the underlying mechanisms driving energy consumption behavior but also suggest that fostering a sense of community fit might be a more effective strategy for promoting sustainable energy practices.

Pembelajaran Pendidikan Agama Islam Berbasis Teknologi Dalam Era Digital Untuk Peningkatan Kepribadian Siswa Di SMK Andalusia 1 Wonosobo

Various forms of innovation and creation are needed in the field of education because in order to advance education, it has always undergone metamorphosis over thousands of years. The current behavior of Indonesian students is reflected in their worrying personalities and tends to decline quite sharply. It was found that many students pay little attention to manners and manners, especially when interacting with senior citizens. The aim of this research is to determine the use of technology in Islamic Religious Education in the digital era. to find out more about the character of class XI students at SMK Andalusia 1 Wonosobo. to find out whether digital media-based Islamic Religious Education courses can help class XI Andalusia 1 Wonosobo students become better human beings. The research methodology used in this research is quantitative. Quantitative research methodology refers to a particular type of research that is orderly, systematic, and well structured from the start until the research design is developed. This kind of research requires a lot of calculations, from data collection, interpretation, to presenting the results. Participants in this research were class XI students at SMK Andalusia 1 Wonosobo. At the conclusion of the study, it may be more acceptable to include figures, tables, graphs, or other displays. The research results showed that based on digital era technology and multiple choice questions, the experimental class (AKL1) obtained an average PAI score of 84.5, with the highest score being 90 and the lowest being 71. In contrast, the control group using traditional techniques had an average score 78.8, with the highest score of 87 and the lowest score of 71. The average pretest and posttest scores for PAI learning based on digital era technology in the two classes above show an increase in the average score in the experimental group compared to what happened in the control group. The average learning outcomes are also higher in the experimental class. Class personality comes in second. Third, utilizing technology in the digital era to teach Islamic Religious Education and help students become better humans. It is clear that there is a significant difference between the experimental class and the control class if the significance value is less than 0.05. class post-test results. The analysis findings show that the children's personalities have developed.

A further examination of growth factors, T helper 1 polarization, and the gut microbiome in major depression: Associations with reoccurrence of illness, cognitive functions, suicidal behaviors, and quality of life

Growth factors, T helper (Th)1 polarization, and the microbiome are involved in the pathophysiology of major depression (MDD). It remains unclear whether the combination of these three pathways could enhance the accuracy of predicting the features of MDD, including recurrence of illness (ROI), suicidal behaviors and the phenome. We measured serum stem cell factor (SCF), stem cell growth factor (SCGF), stromal cell-derived factor-1 (SDF-1), platelet-derived growth factor (PDGF), hepatocyte growth factor (HGF), macrophage-colony stimulating factor (M-CSF) and vascular endothelial growth factor (VEGF), the ratio of serum Th1/Th2 cytokines (zTh1-zTh2), and the abundances of gut microbiome taxa by analyzing stool samples using 16S rDNA sequencing from 32 MDD patients and 37 healthy controls. The results show that serum SCF is significantly lower and VEGF increased in MDD. Adverse childhood experiences (ACE) and ROI are significantly associated with lowered SCF and increasing VEGF. Lifetime and current suicidal behaviors are strongly predicted (63.5%) by an increased VEGF/SCF ratio, Th1 polarization, a gut microbiome enterotype indicating gut dysbiosis, and lowered abundance of Dorea and Faecalobacterium. Around 80.5% of the variance in the phenome's severity is explained by ROI, ACEs, and lowered Parabacteroides distasonis and Clostridium IV abundances. A large part of the variance in health-related quality of life (54.1%) is explained by the VEGF/SCF ratio, Th1 polarization, ACE, and male sex. In conclusion, key features of MDD are largely predicted by the cumulative effects of ACE, Th1 polarization, aberrations in growth factors and the gut microbiome with increased pathobionts but lowered beneficial symbionts.

T cell activation and lowered T regulatory cell numbers are key processes in severe major depressive disorder: Effects of recurrence of illness and adverse childhood experiences

BackgroundMajor depressive disorder (MDD) is characterized by increased T helper (Th)1 polarization, T cell activation (e.g., CD71+ and CD40L+), and cannabinoid receptor type 2 bearing CD20+ B cells; and lower T regulatory (Treg) numbers. AimsTo delineate the effects of adverse childhood experiences (ACEs) and recurrence of illness (ROI) on activated T and CB2-bearing B populations, and Tregs, including FoxP3 + CD152+, FoxP3 + GARP+, and FoxP3 + CB1+ cells. MethodsWe measured ROI, ACEs, the number of activated T cells, Tregs, and CD20 + CB2+ B cells, in 30 MDD patients and 20 healthy controls. ResultsA larger part of the variance in the depression phenome (40.8 %) was explained by increased CD20 + CB2+ and activated T cells, and lowered Tregs. ROI and lifetime suicidal behaviors were significantly and positively associated with CD20 + CB2+, CD3 + CD71+, CD3 + CD40L+, CD4 + CD71+, CD4 + CD40L+, and CD4HLADR+ numbers. ROI was significantly correlated with CD8 + CD40L+ numbers. The sum of ACEs was significantly associated with CD20 + CB2+, CD3 + CD40L+, CD4 + 40 L+ numbers, T cell activation (positively) and Treg (inversely) indices. One replicable latent vector could be extracted from activated T cells, lifetime and current suicidal behaviors, number of depressive episodes, and severity of depression, and 48.8 % of its variance was explained by ACEs. ConclusionsACE-induced activation of T effector and cytotoxic cells and B cells with autoimmune potential, coupled with lowered Treg numbers are a key component of depression. The findings indicate that increasing ROI, the phenome of depression and suicidal behaviors, are caused by autoimmune processes, which are the consequence of ACEs and increasing sensitization of immune responses.