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Nitrogen (N) availability is a powerful controller of soil carbon (C) cycling in temperate forests, affecting plant productivity and microbial activities. Enhanced rhizosphere input from increased plant productivity can stimulate the decomposition of native soil organic matter (SOM), termed the "priming effect", with an effect size that is affected by N availability. Using soils from N-fertilization field-experiments conducted in larch and mixed forest plantations, we investigated how N availability influenced the priming of soil organic C (SOC) mineralization and soil organic N (SON) mineralization by adding 13C-labelled glucose semi-continuously (every third day) to simulate the semi-continuous delivery of rhizosphere inputs. We found that semi-continuous additions of glucose induced a repeating pattern for the priming of SOC mineralization with an initial decrease followed by an increase. This repeating pattern of SOC mineralization reversely coincided with repeating dynamics in the level of bacterial growth which first increased followed by a decrease. The labile C additions induced a gradually increasing priming of SON mineralization, which was greater than the priming of SOC mineralization (i.e. "selective microbial N-mining"). The priming of SOC mineralization and SON mineralization were both reduced by N fertilization. Increased priming of SON mineralization was related to stimulated bacterial growth and changes in the microbial C use efficiency. These responses suggested that increased microbial demand for N drove the observed N-mining responses. This microbial N-mining could not be explained by increased oxidative enzyme activities, and was instead linked to microbial growth. In the larch forest with high C-quality, the high priming of SOM mineralization were linked to bacterial growth, while in the mixed forest with low C-quality, the high levels of priming of SOM mineralization was linked to fungal growth. We also observed that labile C input initially decoupled the C and N mineralization from SOM. Within 16 days, however, a new equilibrium developed, where both C and N mineralization from SOM were similarly enhanced by labile C input. Overall, our results suggest that semi-continuous rhizosphere inputs can induce a sustained priming of SOM mineralization driven by the microbial demand for N – increasing the release of CO 2 – but that N fertilization could reduce the soil C loss, contributing to enhanced soil C sequestration. • Semi-continuous C additions primed a repeating pattern of SOC mineralization. • Glucose primed N-mining driven by microbial growth demands. • Oxidase enzyme activities did not explain the priming of SOM mineralization. • Differences in forest type SOC-quality drove distinct priming effects. • After C addition, SOC mineralization was transiently decoupled from that of SON. [ABSTRACT FROM AUTHOR]

Purpose Surgery is regarded as a common treatment option for patients with mesial temporal lobe epilepsy (MTLE) as a result of hippocampal sclerosis (HS). However, approximately one-third of patients with intractable epilepsy did not become seizure-free after tailored resection strategies. It would be compelling to identify predictive factors of postoperative seizure outcomes. Our aim was to assess the correlation between HS classification and long-term postoperative seizure outcome in patients with MTLE due to HS. Methods To investigate HS classification, semi-quantitative analysis and immunohistochemical staining of neuronal nuclei (NeuN) were performed on 100 postoperative hippocampal specimens. All patients had a 1–7 year postoperative follow-up. The postoperative seizure outcome was evaluated using International League Against Epilepsy (ILAE) outcome classification. Results Three types of HS were recognized. The highest incidence of initial precipitating injury (IPI) was noted in the HS ILAE type 1 group (53.1%). The most favorable long-term seizure outcome was also noted in the HS ILAE type 1 group. The shortest epilepsy duration was recorded in the HS ILAE type 2 group (mean epilepsy duration = 6.64 ± 5.83 years). The completely seizure free rate of patients in all groups declined with an increase in time. Conclusions Our study for the first time demonstrated a significant correlation between HS ILAE types and long-term postoperative seizure outcome in patients with MTLE due to HS. Therefore, HS ILAE types have predictive value in long-term seizure outcome following epilepsy surgery. [ABSTRACT FROM AUTHOR]

Vector diffraction theory is employed to investigate the focusing properties of the Gaussian beams with superimposed left-handed and right-handed helical phase fronts theoretically. Numerical simulations show that the intensity distribution in focal region can be altered considerably by adjusting topological charge m corresponding to right-handed helix and topological charge n corresponding to left-handed helix. Many novel focal pattern may occur. It was shown that the focal pattern evolves from one intensity peak to multiple intensity peaks with changing the topological charge m and n, and all the intensity peaks form in a circle. As the number of intensity peaks is the sum of m and n, the focal pattern can be controlled through adjusting the topological charge m and n. And in order to show the possible applications of these alterable foci pattern, some optical gradient force distributions were also calculated and illuminated. [ABSTRACT FROM AUTHOR]

Highlights: [•] The PDMS/MMT-CTAB-HEP films were prepared by solution intercalation technique. [•] The mechanical properties of PDMS/2wt% MMT-CTAB-HEP films were increased. [•] The PDMS/2wt% MMT-CTAB-HEP film showed excellent hemocompatibility. [ABSTRACT FROM AUTHOR]

Climate warming and shrubification will affect soil carbon (C) cycling in arctic ecosystems. Rhizosphere inputs from increased plant productivity by shrubification may stimulate the mineralization of old soil organic matter (SOM), termed the "priming effect". However, increased soil nitrogen (N) availability due to warming-accelerated mineralization, and litter inputs associated with shrubification could modulate this response. In this study, we investigated how N-availability affects the priming of SOM mineralization in subarctic soils by adding labile organic matter (OM) including 13C-glucose with and without mineral N, or 13C-alanine, into soils with different N availabilities resulting from inorganic N and/or litter addition field-treatments. Rather than as a single pulse addition, labile OM additions were administered semi-continuously every other day to simulate rhizosphere conditions. We found that semi-continuous additions of labile OM induced a sustained priming of SOM mineralization, and this was linked to a sustained stimulation of bacterial and fungal growth over time, despite a reduced microbial growth efficiency. The priming of soil N mineralization was higher than the priming of soil C mineralization, indicating a selective microbial N-mining that was particularly pronounced in more N-poor soils. However, microbial N-mining showed a declining trend over time, suggesting a shift from the most N-rich compounds to less N-rich compounds, presumably as reservoirs were exhausted. The priming effect controlled by N-mining was associated with a stimulation of bacterial and fungal growth depending on the form of labile OM: Alanine induced higher priming of soil C mineralization by stimulating bacterial growth, while glucose induced lower priming of soil C mineralization by stimulating fungal growth. These results indicate that bacteria and fungi can both drive the priming of SOM mineralization in subarctic soils. Based on microbial biomass and growth rates, it could be estimated that over 90% of the observed priming of both soil C and N mineralization were due to changes in turnover of "old" SOM rather than of the microbial biomass pool (i.e. "real" rather than "apparent" priming). Overall, our findings suggest that increased rhizosphere inputs could increase soil N availability by enhanced microbial N-mining, generating a positive feedback to plant productivity in the subarctic. In contrast, increased soil N availability could reduce soil C release through alleviated microbial demand for N. • Semi-continuous delivery of labile OM primed sustained SOM mineralization. • Glucose stimulated fungal growth and generated a lower SOM mineralization. • Alanine stimulated bacterial growth and generated a higher SOM mineralization. • The priming effect was driven by selective N-mining that declined over time. • Enhanced soil N availability reduced priming of SOM mineralization. [ABSTRACT FROM AUTHOR]

Soil microorganisms play an integral role in the regulation of carbon (C) cycling. In high-latitude ecosystems, climate warming is leading to higher plant productivity, shrub expansion and faster nutrient cycling; all of which increase resource availability to soil microorganisms. To understand how a legacy of enhanced resource availability affects the functional traits of microbial communities, and their feedbacks to further environment change, we collected soils from a field-experiment in a subarctic dry heath, where the consequences of climate warming were simulated by adding birch litter or inorganic N as either chronic additions during three years or as a single extreme addition. Soils were then re-exposed to the same resource or a modified resource environment in the laboratory and were monitored for 2 months. We hypothesized that a history of resource input would affect microbial functional profiles, which could result in two possibilities: 1) soil microbes exposed to a historical resource input would perform better when presented with the same resource, because the communities would be specialized to use the added resource, or 2) soil microbes would perform better when presented with a new resource, because the added resource would relieve the nutrient limitation induced by the previous resource input. We also hypothesized that with the same resource, a chronic and long-term input (i.e., a press disturbance) would select for K-strategists (i.e., fungi), while a sudden and large input (i.e., a pulse disturbance) would select for r-strategists (i.e., bacteria). We observed that bacteria in soils exposed to a history of N input showed a stronger growth response to new litter addition, while fungi in soils with a history of litter input showed a stronger growth response to both new litter and new N additions. When presented with new litter, the increase of fungal growth in soil from the extreme litter field-treatment was lower than in the chronic litter field-treatment, demonstrating that a pulse disturbance could weaken the stimulation of fungal growth. When presented with new litter, the increases of bacterial growth did not differ between the chronic N field-treatment and the extreme N field-treatment, suggesting that bacterial responses were not favoured by a press disturbance. We conclude that the enhanced resource availabilities expected in warming arctic soils will generate a positive microbial feedback to climate change. • A legacy of enhanced resource availability modulated microbial resource-responses. • A legacy of N input strengthened the bacterial growth-response to new litter. • A legacy of litter input strengthened the fungal growth-response to both new litter and N. • Fungal resource-responses were strengthened more by longer-term, stable change. [ABSTRACT FROM AUTHOR]

Intracerebral hemorrhage (ICH) is acknowledged as a serious clinical problem lacking effective treatments. And caspase-1-mediated inflammatory response happened during the progression of ICH. Therefore, we aimed to investigate the effects of caspase-1 inhibitor Ac-YVAD-cmk on ICH. Microglia cells were isolated and activated by thrombin for 24 h. Then the transcript and protein expressions of NLRP3 and inflammatory factors were assessed by RT-PCR and western blotting. Moreover, Ac-YVAD-cmk was injected into the ICH model. The mNSS and brain water content were tested at 24 h post-ICH. Finally, the pathological changes of microglia activation following ICH were discovered by the immunohistochemical and HE staining ways. Ac-YVAD-cmk inhibited the activation of pro-caspase-1 and decreased brain edema, in association with decreasing activated microglia and the expression of inflammation-related factors at 24 h post-ICH. Consequently, Ac-YVAD-cmk reduced the release of mature IL-1β/IL-18 in perihematoma, improved the behavioral performance, and alleviated microglia in perihematoma region in ICH rats. These results indicate that caspase-1 could amplify the plural inflammatory responses in the ICH. Administration of Ac-YVAD-cmk has the potential to be a novel therapeutic strategy for ICH. • The Ac-YVAD-cmk reduced the release of IL-1β/IL-18 from activated microglia in vitro. • Ac-YVAD-cmk improved the behavioral performance. • Ac-YVAD-cmk alleviated microglia in perihematoma region in ICH rats. [ABSTRACT FROM AUTHOR]