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Extreme waterfall conditions cause partition of aquatic ecosystems of waterfall streams into discrete zones. To assess the features of aquatic ecosystems that function in waterfall streams, macroinvertebrate communities of the Tevenek River (Lake Teletskoye basin, Northeastern Altai) were examined above and below the waterfall. The diversity, abundance, and biomass of macroinvertebrates were higher above than below the barriers. Gammarus korbuensis showed the most significant decrease in number (from 3.1 to 2.3 thousand ind./m2) probably due to the intensive use of amphipods as food for fish living in Lake Teletskoye. An additional factor in favor of the high species richness of macroinvertebrates in the upper reaches is the geomorphology of the waterfall river valley that contributes to the formation of more diverse conditions above the waterfalls. Hydrobiological studies of waterfall streams can help to understand the restructuring of benthic communities divided as a result of the human impact.

Purpose of ReviewOver the last decade, evidence suggests that a combination of behavioral and neuroimaging findings can help illuminate changes in functional dysconnectivity in schizophrenia. We review the recent connectivity literature considering several vital models, considering connectivity findings, and relationships with clinical symptoms. We reviewed resting state fMRI studies from 2017 to 2023. We summarized the role of two sets of brain networks (cerebello-thalamo-cortical (CTCC) and the triple network set) across three hypothesized models of schizophrenia etiology (neurodevelopmental, vulnerability-stress, and neurotransmitter hypotheses).Recent FindingsThe neurotransmitter and neurodevelopmental models best explained CTCC-subcortical dysfunction, which was consistently connected to symptom severity and motor symptoms. Triple network dysconnectivity was linked to deficits in executive functioning, and the salience network (SN)–default mode network dysconnectivity was tied to disordered thought and attentional deficits.SummaryThis paper links behavioral symptoms of schizophrenia (symptom severity, motor, executive functioning, and attentional deficits) to various hypothesized mechanisms.

•Contralesional TMS effects strongly depend on the ipsilesional structural integrity.•The impact of the ipsilesional structural reserve is regional specific.•Individual functional and structural data could optimize treatment strategies. The concept of structural reserve in stroke reorganization assumes that the relevance of the contralesional hemisphere strongly depends on the brain tissue spared by the lesion in the affected hemisphere. Recent studies, however, have indicated that the contralesional hemisphere's impact exhibits region-specific variability with concurrently existing maladaptive and supportive influences. This challenges traditional views, necessitating a nuanced investigation of contralesional motor areas and their interaction with ipsilesional networks. Our study focused on the functional role of contralesional key motor areas and lesion-induced connectome disruption early after stroke. Online TMS data of twenty-five stroke patients was analyzed to disentangle interindividual differences in the functional roles of contralesional primary motor cortex (M1), dorsal premotor cortex (dPMC), and anterior interparietal sulcus (aIPS) for motor function. Connectome-based lesion symptom mapping and corticospinal tract lesion quantification were used to investigate how TMS effects depend on ipsilesional structural network properties. At group and individual levels, TMS interference with contralesional M1 and aIPS but not dPMC led to improved performance early after stroke. At the connectome level, a more disturbing role of contralesional M1 was related to a more severe disruption of the structural integrity of ipsilesional M1 in the affected motor network. In contrast, a detrimental influence of contralesional aIPS was linked to less disruption of the ipsilesional M1 connectivity. Our findings indicate that contralesional areas distinctively interfere with motor performance early after stroke depending on ipsilesional structural integrity, extending the concept of structural reserve to regional specificity in recovery of function.

The development of new approaches indirectly measuring the structural disconnectome has recently led to an increase in studies investigating pairwise structural disconnections following brain damage. Previous studies jointly analyzed patients with left hemispheric and patients with right hemispheric lesions when investigating a behavior of interest. An alternative approach would be to perform analyses separated by hemisphere, which has been applied in only a minority of studies to date. The present simulation study investigated whether joint or separate analyses (or both equally) are appropriate to reveal the ground truth disconnections. In fact, both approaches resulted in very different patterns of disconnection. In contrast to analyses separated by hemisphere, joint analyses introduced a bias to the disadvantage of intra‐hemispheric disconnections. Intra‐hemispheric disconnections were statistically underpowered in the joint analysis and thus surpassed the significance threshold with more difficulty compared to inter‐hemispheric disconnections. This statistical imbalance was also shown by a greater number of significant inter‐hemispheric than significant intra‐hemispheric disconnections. This bias from joint analyses is based on mechanisms similar to those underlying the “partial injury problem.” We therefore conclude that pairwise structural disconnections in patients with unilateral left hemispheric and with unilateral right hemispheric lesions exhibiting a specific behavior (or disorder) of interest should be studied separately by hemisphere rather than in a joint analysis. We simulated pairwise structural disconnections and compared two approaches of analyzing brain damage: unilateral lesions from both hemispheres together or separated by hemisphere. In contrast to the separate analyses, the joint analysis led to biased results: intra‐hemispheric disconnections were statistically underpowered and therefore missed more often compared to inter‐hemispheric disconnections.

BACKGROUND Structural disconnectivity was found to precede dementia. Global white matter abnormalities might also be associated with postoperative delirium (POD). METHODS We recruited older patients (≥65 years) without dementia that were scheduled for major surgery. Diffusion kurtosis imaging metrics were obtained preoperatively, after 3 and 12 months postoperatively. We calculated fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK), and free water (FW). A structured and validated delirium assessment was performed twice daily. RESULTS Of 325 patients, 53 patients developed POD (16.3%). Preoperative global MD (standardized beta 0.27 [95% confidence interval [CI] 0.21–0.32] p < 0.001) was higher in patients with POD. Preoperative global MK (−0.07 [95% CI −0.11 to (−0.04)] p < 0.001) and FA (0.07 [95% CI −0.10 to (−0.04)] p < 0.001) were lower. When correcting for baseline diffusion, postoperative MD was lower after 3 months (0.05 [95% CI −0.08 to (−0.03)] p < 0.001; n = 183) and higher after 12 months (0.28 [95% CI 0.20–0.35] p < 0.001; n = 45) among patients with POD. DISCUSSION Preoperative structural disconnectivity was associated with POD. POD might lead to white matter depletion 3 and 12 months after surgery.

Despite the increasing body of evidence supporting the hypothesis of schizophrenia as a disconnection syndrome, studies of resting-state EEG Source Functional Connectivity (EEG-SFC) in people affected by schizophrenia are sparse. The aim of the present study was to investigate resting-state EEG-SFC in 77 stable, medicated patients with schizophrenia (SCZ) compared to 78 healthy volunteers (HV). In order to study the effect of illness duration, SCZ were divided in those with a short duration of disease (SDD; n = 25) and those with a long duration of disease (LDD; n = 52). Resting-state EEG recordings in eyes closed condition were analyzed and lagged phase synchronization (LPS) indices were calculated for each ROI pair in the source-space EEG data. In delta and theta bands, SCZ had greater EEG-SFC than HV; a higher theta band connectivity in frontal regions was observed in LDD compared with SDD. In the alpha band, SCZ showed lower frontal EEG-SFC compared with HV whereas no differences were found between LDD and SDD. In the beta1 band, SCZ had greater EEG-SFC compared with HVs and in the beta2 band, LDD presented lower frontal and parieto-temporal EEG-SFC compared with HV. In the gamma band, SDD had greater connectivity values compared with LDD and HV. This study suggests that resting state brain network connectivity is abnormally organized in schizophrenia, with different patterns for the different EEG frequency components and that EEG can be a powerful tool to further elucidate the complexity of such disordered connectivity.

The transformation pathways between low-energy naphthalene isomers are studied by investigating the topology of the energy landscape of this astrophysically relevant molecule. The threshold algorithm is used to identify the minima basins of the isomers on the potential energy surface of the system and to evaluate the probability flows between them. The transition pathways between the different basins and the associated probabilities were investigated for several lid energies up to 11 eV, this value being close to the highest photon energy in the interstellar medium (13.6 eV). More than a hundred isomers were identified and a set of 23 minima was selected among them, on the basis of their energy and probability of occurrence. The return probabilities of these 23 minima and the transition probabilities between them were computed for several lid energies up to 11 eV. The first connection appeared at 3.5 eV while all minima were found to be connected at 9.5 eV. The local density of state was also sampled inside their respective basins. This work gives insight into both energy and entropic barriers separating the different basins, which also provides information about the transition regions of the energy landscape.

KReg is the category of compact regular frames and frame homomorphisms. A class of KReg frames H is a hull class provided that: (i) H is closed under isomorphic copies; (ii) for every F ∈ KReg there exist an h F ∈ H and a morphism h F such that F ≤ h F h F is essential; (iii) if F ≤ ϕ H is essential and H ∈ H , then there exists h ϕ : h F ⟶ H for which ϕ = h ϕ · h F . This work provides techniques for identifying and generating hull classes in KReg . Moreover, for a compact regular frame F , we introduce and investigate various properties of projectability and disconnectivity of F and prove that for each property, P , the class of KReg -objects that satisfy P is a hull class in KReg . In addition, we provide examples of KReg hull classes that are not characterized by some form of projectability/disconnectivity and examples of classes of KReg -objects that are not hull classes.

Geographic concerns for spatial relationships lie at the heart of geomorphic applications in environmental management. The way in which landscape compartments fit together in a catchment influences the operation of biophysical fluxes, and hence the ways in which disturbance responses are mediated over time. These relationships reflect the connectivity of the landscape. A nested hierarchical framework that emphasizes differing forms of (dis)connectivity in catchments is proposed. This field-based geomorphic tool can be used to ground the application of modelling techniques in analysis of catchment-scale biophysical fluxes.

This article explores the complex, multi-layered mechanisms of internet censorship in China, emphasizing its role as both a tool of control over public engagement and a mechanism for elites to disconnect themselves from spaces of public scrutiny, and avoid potential threats such as doxxing by bottom-up populist online movements. Through in-depth interviews with social media users, this study investigates how individuals perceive, assess, and navigate the boundaries of internet censorship, focusing on their awareness of censorship practices, the assessment of sensitive content, and the tactics they employ to circumvent restrictions. We further examine how a sophisticated censorship mechanism—comprising self-censorship, platform censorship, and physical enforcement—works to disconnect netizens from grassroots collective actions. The findings reveal that internet censorship in China not only regulates online populist activism but also serves as a protective shield for elites, allowing them to curate a controlled digital space that suppresses critical discourse. By highlighting the ways in which both ordinary users and elites navigate the challenges of digital engagement in this heavily regulated environment, this study provides theoretical insights into the practice of disconnectivity as an elite privilege. It enhances our understanding of the interplay between connectivity, censorship, and disconnectivity in shaping the digital landscape and its implications for social change and political engagement in China and beyond.