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Rapid Arctic warming is causing permafrost to thaw and exposing large quantities of soil organic carbon (C) to potential decomposition. In dry upland tundra systems, subsidence from thawing permafrost can increase surface soil moisture resulting in higher methane (CH4) emissions from newly waterlogged soils. The proportion of C released as carbon dioxide (CO2) and CH4 remains uncertain as previously dry landscapes transition to a thawed state, resulting in both wetter and drier microsites. To address how thaw and moisture interact to affect total C emissions, we measured CH4 and CO2 emissions from paired chambers across thaw and moisture gradients created by nine years of experimental soil warming in interior Alaska. Cumulative growing season (May–September) CH4 emissions were elevated at both wetter (216.1–1,099.4 mg CH4-C m−2) and drier (129.7–392.3 mg CH4-C m−2) deeply thawed microsites relative to shallow thaw (55.6–215.7 mg CH4-C m−2) and increased with higher deep soil temperatures and permafrost thaw depth. Interannual variability in CH4 emissions was driven by wet conditions in graminoid-dominated plots that generated >70% of emissions in a wet year. Shoulder season emissions were equivalent to growing season CH4 emissions rates in the deeply thawed, warmed soils, highlighting the importance of non-growing season CH4 emissions. Net C sink potential was reduced in deeply thawed wet plots by 4%–42%, and by 3.5%–8% in deeply thawed drier plots due to anaerobic respiration, suggesting that some dry upland tundra landscapes may transition into stronger CH4 sources in a warming Arctic.

Higher temperatures in northern latitudes will increase permafrost thaw and stimulate above- and belowground plant biomass growth in tundra ecosystems. Higher plant productivity increases the input of easily decomposable carbon (C) to soil, which can stimulate microbial activity and increase soil organic matter decomposition rates. This phenomenon, known as the priming effect, is particularly interesting in permafrost because an increase in C supply to deep, previously frozen soil may accelerate decomposition of C stored for hundreds to thousands of years. The sensitivity of old permafrost C to priming is not well known; most incubation studies last less than one year, and so focus on fast-cycling C pools. Furthermore, the age of respired soil C is rarely measured, even though old C may be vulnerable to labile C inputs. We incubated soil from a moist acidic tundra site in Eight Mile Lake, Alaska for 409 days at 15 °C. Soil from surface (0–25 cm), transition (45–55 cm), and permafrost (65–85 cm) layers were amended with three pulses of uniformly 13 C-labeled glucose or cellulose every 152 days. Glucose addition resulted in positive priming in the permafrost layer 7 days after each substrate addition, eliciting a two-fold increase in cumulative soil C loss relative to unamended soils with consistent effects across all three pulses. In the transition and permafrost layers, glucose addition significantly decreased the age of soil-respired CO 2 -C with Δ 14 C values that were 115‰ higher. Previous field studies that measured the age of respired C in permafrost regions have attributed younger Δ 14 C ecosystem respiration values to higher plant contributions. However, the results from this study suggest that positive priming, due to an increase in fresh C supply to deeply thawed soil layers, can also explain the respiration of younger C observed at the ecosystem scale. We must consider priming effects to fully understand permafrost C dynamics, or we risk underestimating the contribution of soil C to ecosystem respiration.

In the last few decades, temperatures in the Arctic have increased twice as much as the rest of the globe. As permafrost thaws in response to this warming, large amounts of soil organic matter may become vulnerable to decomposition. Microbial decomposition will release carbon (C) from permafrost soils, however, warmer conditions could also lead to enhanced plant growth and C uptake. Field and modeling studies show high uncertainty in soil and plant responses to climate change but there have been few studies that reconcile field and model data to understand differences and reduce uncertainty. Here, we evaluate gross primary productivity (GPP), ecosystem respiration (Reco), and net ecosystem C exchange (NEE) from eight years of experimental soil warming in moist acidic tundra against equivalent fluxes from the Community Land Model during simulations parameterized to reflect the field conditions associated with this manipulative field experiment. Over the eight-year experimental period, soil temperatures and thaw depths increased with warming in field observations and model simulations. However, the field and model results do not agree on warming effects on water table depth; warming created wetter soils in the field and drier soils in the models. In the field, initial increases in growing season GPP, Reco, and NEE to experimentally-induced permafrost thaw created a higher C sink capacity in the first years followed by a stronger C source in years six through eight. In contrast, both models predicted linear increases in GPP, Reco, and NEE with warming. The divergence of model results from field experiments reveals the role subsidence, hydrology, and nutrient cycling play in influencing the C flux responses to permafrost thaw, a complexity that the models are not structurally able to predict, and highlight challenges associated with projecting C cycle dynamics across the Arctic.

Chitosan (CTS) and collagen (Coll) are natural biomaterials that have been extensively used in tissue engineering or wound healing applications, either separately or as composite materials. Most methods to fabricate CTS/Coll matrices employ chemical crosslinking to obtain solid and stable scaffolds with the necessary porosity and mechanical properties to facilitate regeneration. In this study, we comparatively assessed the physicochemical properties of 3D scaffolds loaded with a cross-linker, glyoxal. Using a scanning electron microscope, we evaluated the microstructure of resultant matrices and their mechanistic testing by the determination of the compressive modulus (Emod), the maximum force (Fmax), thermogravimetric analysis (TG), Fourier Transform Infrared Spectroscopy–Attenuated Total Reflectance (FTIR-ATR), and proliferation rate in vitro using human epidermal keratinocytes and dermal fibroblasts cultured in presence of melatonin solution (10−5 M). We observed that enhanced content of collagen (50CTS/50Coll or 20CTS/80Coll compared to 80CTS/20Coll) significantly elevated the physicochemical capacities of resultant materials. Besides, presence of 5% glyoxal increased porosity, Emod and Fmax, compared to scaffolds without glyoxal. Finally, keratinocytes and dermal fibroblasts cultured on subjected matrices in presence of melatonin revealed a prominently enhanced growth rate. This indicates that the combination of glyoxal and melatonin make it imperative to consider these materials as a promising approach for targeting skin tissue engineering or regenerative dermatology.

Rapid Arctic warming is causing permafrost to thaw and exposing large quantities of soil organic carbon (C) to potential decomposition. In dry upland tundra systems, subsidence from thawing permafrost can increase surface soil moisture resulting in higher methane (CH4) emissions from newly waterlogged soils. The proportion of C released as carbon dioxide (CO2) and CH4 remains uncertain as previously dry landscapes transition to a thawed state, resulting in both wetter and drier microsites. To address how thaw and moisture interact to affect total C emissions, we measured CH4 and CO2 emissions from paired chambers across thaw and moisture gradients created by nine years of experimental soil warming in interior Alaska. Cumulative growing season (May–September) CH4 emissions were elevated at both wetter (216.1–1,099.4 mg CH4-C m−2) and drier (129.7–392.3 mg CH2-C m−2) deeply thawed microsites relative to shallow thaw (55.6–215.7 mg CH4-C m−2) and increased with higher deep soil temperatures and permafrost thaw depth. Interannual variability in CH4 emissions was driven by wet conditions in graminoid-dominated plots that generated >70% of emissions in a wet year. Shoulder season emissions were equivalent to growing season CH4 emissions rates in the deeply thawed, warmed soils, highlighting the importance of non-growing season CH4 emissions. Net C sink potential was reduced in deeply thawed wet plots by 4%–42%, and by 3.5%–8% in deeply thawed drier plots due to anaerobic respiration, suggesting that some dry upland tundra landscapes may transition into stronger CH2 sources in a warming Arctic. [ABSTRACT FROM AUTHOR]

Many invasions, like the wide-spread establishment of annual grasses and forbs in semi-arid shrublands, are associated with climate change. In order to predict ecosystem carbon (C) storage it is critical that we understand how invasion affects soil respiration (Rt). Because plants and microbes have different seasonal dynamics, determining the relative contribution of autotrophic (Ra) and heterotrophic (Rh) respiration provides critical insight into soil C processes. Using automated soil respiration measurements and root exclusion cores we evaluated the moisture and temperature sensitivity of Rt and Rh and calculated the contribution of Ra in native shrub and invaded areas. Invasion increased cumulative Rt by 40% from 695 (±51) gCm-2 under shrubs to 1050 gCm-2 (±44) in invaded areas. Cumulative Rh did not change but invasion altered the seasonal pattern of Rh. Throughout the season Rt and Rh responded positively to temperature increases when soils were wet and negatively when soils were dry. Invasion increased temperature sensitivity of Rt and Rh in wet soils and decreased temperature sensitivity in dry soils. The altered temperature sensitivity of invasives was attributed largely to differences in phenology. Early phenology of invasive grasses caused rapid Ra increases early in the season; late phenology of invasive forbs resulted in the surprising maintenance of diurnal Ra and Rh signals despite high temperatures and low soil moisture. Invasion extended the respiration season of the system. Ability of the invasive community to withstand high temperatures and drought could confer greater resilience if temperature and precipitation patterns in the region change. The high contribution of Ra by invasive annuals means ecosystem C storage will depend heavily on seasonal rainfall dynamics and productivity of invasive annuals. In semi-arid ecosystems even small scale changes in plant community composition alter Rt, Ra and Rh and should be considered when attempting to predict Rt. [ABSTRACT FROM AUTHOR]

AIM: Schizophrenia enormously impacts the lives of the patients who have this psychiatric disorder. This study addresses the lived experience of grief in schizophrenia. METHOD: A qualitative study based on the grounded theory was designed. Ten patients were interviewed in depth on their feelings of loss and ways of coping. RESULTS: All respondents experienced significant feelings of loss. Internal and external losses were distinguished. Respondents dealt with their losses by accepting their diagnosis and treatment, identifying with other patients, learning about schizophrenia, and searching for meaning. DISCUSSION: Respondents were able to identify their significant losses and verbalize the accompanied feelings. They went through an intensive grieving process that to a certain extent led to coming to terms. During the interviews, the presence of grief was evident, whereas clinical depression was excluded. CLINICAL IMPLICATIONS: Interventions may be improved by the following factors: (a) optimal assessment and treatment of symptoms; (b) adequate information about symptoms, treatment and its effects, and prognosis; (c) opportunities to identify with other patients; (d) strengthening of social support; and (e) a relationship of trust with care providers based on an accepting attitude. Copyright © 2009 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

Intracerebral hemorrhages (ICH) during implantation of stereo-EEG electrodes are rare. The impact of tobacco-free nicotine consumption on periprocedural bleeding is uncertain. We present a 20+ year-old man with drug-resistant epilepsy who underwent stereo-EEG with 17 depth electrodes. Within a few days after insertion, the patient developed multiple ICHs in the electrode trajectories and an intradural hemorrhage after a diagnostic spinal tap. We performed the investigation of the clotting system and whole-exome sequencing (WES). WES identified a heterozygous mutation c.4698G>T, p.(Trp1566Cys) in COL4A2 (NM_001846.4) encoding a collagen type-IV alpha-2 chain inherited from his seemingly healthy mother. As COL4A2 mutations had been identified in four adult patients with ICH we postulated that the identified variant presents a potential risk factor. Notably, mutations encoding other collagens have been linked to cerebral hemorrhages (COL4A1) and increased propensity to trigger ICH upon smoking (COL1A2). Our patient consumed at least 24 oral nicotine pouches (containing 11 mg nicotine each) per day. We consider the patient's COL4A2 mutation in combination with his substantial nicotine consumption as likely predisposition to multiple ICHs precipitated by stereo-EEG. Patients with nicotine consumption and any collagen mutation may have a substantially higher risk for hemorrhagic complications in SEEG and other neurosurgical procedures. PLAIN LANGUAGE SUMMARY: A young man with drug-resistant epilepsy experienced multiple intracerebral hemorrhages after implantation of SEEG electrodes for presurgical evaluation and concomitantly a intradural hemorrhage after a lumbar spinal tap. A collagen IV mutation of unclear significance and heavy use of oral nicotine pouches were the only potential risk factors identified. As collagen mutations were previously described risk factors and smoking in particular worsens the bleeding risk in collagen mutations, further research is warranted to prevent hemorrhages in neurosurgical procedures. Nicotine consumption in any form is a preventable risk factor., (© 2024 The Author(s). Epilepsia Open published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)

Objectives: To review the evidence on the clinical value of magnetic source imaging (MSI) in patients with refractory focal epilepsy without evidence for an epileptogenic lesion on magnetic resonance imaging ("MRI-negative" or "non-lesional MRI")., Methods: We conducted a systematic literature search on PUBMED, which was extended by researchrabbit.ai using predefined criteria to identify studies that applied MSI in MRI-negative patients with epilepsy. We extracted data on patient characteristics, MSI methods, localization results, surgical outcomes, and correlation with other modalities., Results: We included 23 studies with a total of 512 non-lesional epilepsy patients who underwent MSI. Most studies used equivalent current dipole (ECD) models to estimate the sources of interictal epileptic discharges (IEDs). MEG detected IEDs in 32-100% of patients. MSI results were concordant with other modalities, such as EEG, PET, and SPECT, in 3892% of cases. If MSI concordant surgery was performed, 52-89% of patients achieved seizure freedom. MSI contributed to the decision-making process in 28-75% of cases and altered the surgical plan in 5-33% of cases., Conclusions: MSI is a valuable diagnostic tool for MRI-negative patients with epilepsy, as it can detect and localize IEDs with high accuracy and sensitivity, and provides useful information for surgical planning and predicts outcomes. MSI can also complement and refine the results of other modalities, such as EEG and PET, and optimize the use of invasive recordings. MSI should be considered as part of the presurgical evaluation, especially in patients with non-lesional refractory epilepsy.

Plant phenology, the timing of recurrent biological events, shows key and complex response to climate warming, with consequences for ecosystem functions and services. A key challenge for predicting plant phenology under future climates is to determine whether the phenological changes will persist with more intensive and long-term warming. Here, we conducted a meta-analysis of 103 experimental warming studies around the globe to investigate the responses of four phenophases - leaf-out, first flowering, last flowering, and leaf coloring. We showed that warming advanced leaf-out and flowering but delayed leaf coloring across herbaceous and woody plants. As the magnitude of warming increased, the response of most plant phenophases gradually leveled off for herbaceous plants, while phenology responded in proportion to warming in woody plants. We also found that the experimental effects of warming on plant phenology diminished over time across all phenophases. Specifically, the rate of changes in first flowering for herbaceous species, as well as leaf-out and leaf coloring for woody species, decreased as the experimental duration extended. Together, these results suggest that the real-world impact of global warming on plant phenology will diminish over time as temperatures continue to increase., (© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)

Background: Enterobacter cloacae complex (ECCO) comprises closely related Enterobacterales, causing a variety of infections ranging from mild urinary tract infections to severe bloodstream infections. ECCO has emerged as a significant cause of healthcare-associated infections, particularly in neonatal and adult intensive care., Aim: The Enterobacter Cloacae COMplex PASsive Surveillance (EC-COMPASS) aims to provide a detailed multi-centre overview of ECCO epidemiology and resistance patterns detected in routine microbiological diagnostics in four German tertiary-care hospitals., Methods: In a sentinel cluster of four German tertiary-care hospitals, all culture-positive ECCO results between 1 st January 2020 and 31 st December 2022, were analysed based on Hybase® laboratory data., Findings: Analysis of 31,193 ECCO datasets from 14,311 patients revealed a higher incidence in male patients (P<0.05), although no significant differences were observed in ECCO infection phenotypes. The most common sources of ECCO were swabs (42.7%), urine (17.5%), respiratory secretions (16.1%), blood cultures (8.9%) and tissue samples (5.6%). The annual bacteraemia rate remained steady at approximately 33 cases per hospital. Invasive ECCO infections were predominantly found in oncology and intensive care units. Incidences of nosocomial outbreaks were infrequent and limited in scope. Notably, resistance to carbapenems was consistently low., Conclusion: EC-COMPASS offers a profound clinical perspective on ECCO infections in German tertiary-healthcare settings, highlighting elderly men in oncology and intensive care units as especially vulnerable to ECCO infections. Early detection strategies targeting at-risk patients could improve ECCO infection management., (Copyright © 2024 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.)

Background: The psychopathological syndrome of formal thought disorder (FTD) is not only present in schizophrenia (SZ), but also highly prevalent in major depressive disorder and bipolar disorder. It remains unknown how alterations in the structural white matter connectome of the brain correlate with psychopathological FTD dimensions across affective and psychotic disorders., Methods: Using FTD items of the Scale for the Assessment of Positive Symptoms and Scale for the Assessment of Negative Symptoms, we performed exploratory and confirmatory factor analyses in 864 patients with major depressive disorder (n= 689), bipolar disorder (n = 108), or SZ (n = 67) to identify psychopathological FTD dimensions. We used T1- and diffusion-weighted magnetic resonance imaging to reconstruct the structural connectome of the brain. To investigate the association of FTD subdimensions and global structural connectome measures, we employed linear regression models. We used network-based statistic to identify subnetworks of white matter fiber tracts associated with FTD symptomatology., Results: Three psychopathological FTD dimensions were delineated, i.e., disorganization, emptiness, and incoherence. Disorganization and incoherence were associated with global dysconnectivity. Network-based statistics identified subnetworks associated with the FTD dimensions disorganization and emptiness but not with the FTD dimension incoherence. Post hoc analyses on subnetworks did not reveal diagnosis × FTD dimension interaction effects. Results remained stable after correcting for medication and disease severity. Confirmatory analyses showed a substantial overlap of nodes from both subnetworks with cortical brain regions previously associated with FTD in SZ., Conclusions: We demonstrated white matter subnetwork dysconnectivity in major depressive disorder, bipolar disorder, and SZ associated with FTD dimensions that predominantly comprise brain regions implicated in speech. Results open an avenue for transdiagnostic, psychopathology-informed, dimensional studies in pathogenetic research., (Copyright © 2023 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)