Various observations are revealing the widespread occurrence of fast and powerful winds in active galactic nuclei (AGNs) that are distinct from relativistic jets, likely launched from accretion disks ...and interacting strongly with the gas of their host galaxies. During the interaction, strong shocks are expected to form that can accelerate nonthermal particles to high energies. Such winds have been suggested to be responsible for a large fraction of the observed extragalactic gamma-ray background (EGB) and the diffuse neutrino background, via the decay of neutral and charged pions generated in inelastic pp collisions between protons accelerated by the forward shock and the ambient gas. However, previous studies did not properly account for processes such as adiabatic losses that may reduce the gamma-ray and neutrino fluxes significantly. We evaluate the production of gamma rays and neutrinos by AGN-driven winds in detail by modeling their hydrodynamic and thermal evolution, including the effects of their two-temperature structure. We find that they can only account for less than ∼30% of the EGB flux, as otherwise the model would violate the independent upper limit derived from the diffuse isotropic gamma-ray background. If the neutrino spectral index is steep with Γ 2.2, a severe tension with the isotropic gamma-ray background would arise as long as the winds contribute more than 20% of the IceCube neutrino flux in the 10-100 TeV range. At energies 100 TeV, we find that the IceCube neutrino flux may still be accountable by AGN-driven winds if the spectral index is as small as Γ ∼ 2.0-2.1.
As macroscopic three dimensional (3D) architectures show increasing significance, much effort has been devoted to the hierarchical organization of 1D nanomaterials into serviceable macroscopic 3D ...assemblies. How to assemble 1D nanoscale building blocks into 3D hierarchical architectures is still a challenge. Herein we report a general strategy based on the use of ice as a template for assembling 1D nanostructures with high efficiency and good controllability. Free‐standing macroscopic 3D Ag nanowire (AgNW) assemblies with hierarchical binary‐network architectures are then fabricated from a 1D AgNW suspension for the first time. The microstructure of this 3D AgNW network endows it with electrical conductivity and allows it to be made into stretchable and foldable conductors with high electromechanical stability. These properties should make this kind of macroscopic 3D AgNW architecture and it composites suitable for electronic applications.
Silver lining: Macroscopic free‐standing hierarchical 3D architectures can be directly built from monodispersed silver nanowires (AgNW) through a general, versatile ice‐template assembly technique without using any extra functionalization agents or crosslinking agents. The 3D nanowire monoliths have a binary‐network microstructure which provides them with a high electrical conductivity, and, when impregnated with PDMS, great mechanical flexibility.
Abstract
Active galactic nuclei (AGNs) are widely believed to be one of the promising acceleration sites of ultrahigh-energy cosmic rays (CRs). Essentially, AGNs are powered by the gravitational ...energy of matter falling into supermassive black holes. However, the conversion efficiency of gravitational to kinetic energy of CRs in AGNs, which is defined as the baryon loading factor
η
p
, is not well known yet. After being accelerated, high-energy CRs could escape the host galaxy and enter the intracluster medium (ICM). These CRs can be confined within the galaxy cluster and produce
γ
-rays and neutrinos through proton–proton collisions with the ICM. In this paper, we study the diffusion of CRs in galaxy clusters and calculate the diffuse neutrino flux from the galaxy cluster population. Using the latest upper limits on the cumulative unresolved TeV–PeV neutrino flux from galaxy clusters posed by the IceCube Neutrino Observatory, we derive the upper limit of the average baryon loading factor as
η
p
,grav
≲ 2 × 10
−3
− 0.1 for the population of galaxy clusters. This constraint is more stringent than the one obtained from
γ
-ray observation on the Coma cluster.
The neocortex consists of a vast number of diverse neurons that form distinct layers and intricate circuits at the single-cell resolution to support complex brain functions
. Diverse cell-surface ...molecules are thought to be key for defining neuronal identity, and they mediate interneuronal interactions for structural and functional organization
. However, the precise mechanisms that control the fine neuronal organization of the neocortex remain largely unclear. Here, by integrating in-depth single-cell RNA-sequencing analysis, progenitor lineage labelling and mosaic functional analysis, we report that the diverse yet patterned expression of clustered protocadherins (cPCDHs)-the largest subgroup of the cadherin superfamily of cell-adhesion molecules
-regulates the precise spatial arrangement and synaptic connectivity of excitatory neurons in the mouse neocortex. The expression of cPcdh genes in individual neocortical excitatory neurons is diverse yet exhibits distinct composition patterns linked to their developmental origin and spatial positioning. A reduction in functional cPCDH expression causes a lateral clustering of clonally related excitatory neurons originating from the same neural progenitor and a significant increase in synaptic connectivity. By contrast, overexpression of a single cPCDH isoform leads to a lateral dispersion of clonally related excitatory neurons and a considerable decrease in synaptic connectivity. These results suggest that patterned cPCDH expression biases fine spatial and functional organization of individual neocortical excitatory neurons in the mammalian brain.
Recently, the High Altitude Water Cherenkov (HAWC) collaboration reported the discovery of a TeV halo around the Geminga pulsar. The TeV emission is believed to originate from the inverse Compton ...scattering of pulsar-injected electrons/positrons off cosmic microwave background photons. During this time, these electrons should inevitably radiate X-ray photons via synchrotron radiation, providing a useful constraint on the magnetic field in the TeV halo. In this work, we analyze the data of XMM-Newton and Chandra, and obtain an upper limit for the diffuse X-ray flux in a 600″ region around the Geminga pulsar, which is at a level of . By numerically modeling both the X-ray and TeV observations assuming the isotropic diffusion of injected electrons/positrons, we find that the magnetic field inside the TeV halo is required to be <1 G, which is significantly weaker than the typical magnetic field in the interstellar medium. The weak magnetic field together with the small diffusion coefficient inferred from the HAWC observation implies that the Bohm limit of particle diffusion may probably have been achieved in the TeV halo. We also discuss alternative possibilities for the weak X-ray emission, such as the hadronic origin of the TeV emission or a specific magnetic field topology, in which a weak magnetic field and a very small diffusion coefficient might be avoided.
As one of the promising energy storage and conversion systems, supercapacitors (SCs) are highly favored owing to their high power density and good service life. Among all the key components of ...supercapacitor devices, the design and investigation of electrode materials play an essential role in determining the whole electrochemical charge storage performance. Recently, nanocarbon-based materials (e.g., graphene, carbon dots, graphene quantum dots, etc.) have been widely used as SC electrode materials because of their good physical structure and chemical properties, providing a new route to further improve the energy density and life span of SCs. Here, we review the latest progress of nanocarbon-based materials (including nanocarbon and nanocarbon-based composite materials) as electrode materials in SCs application. The recent progress of carbon dots, graphene, carbon nanotubes, and other nanocarbon materials electrodes is summarized, while the capacitance and energy density of the above nanocarbon electrodes still need to be improved. Then, the preparation and performance of nanocarbon-based composite electrodes comprising transition metal oxides, conductive polymer, and metal–organic framework derived porous carbon are reviewed. Finally, we outline major challenges and propose some ideas on building better nanocarbon-based SC electrodes.
Graphic Abstract
Aim
This study aims to evaluate the safety and analgesic efficacy of pre‐mixed nitrous oxide/oxygen mixture treatment of pain induced by dressing change for perianal abscess.
Design
This protocol is ...a randomized, double‐blind, placebo‐controlled trial.
Methods
This study will be implemented in the Hospital of Traditional Chinese Medicine. Subjects enrolled in this study are hospitalized patients who suffered from moderate to severe pain due to dressing change after incision and drainage. Two hundred patients will be selected and randomly assigned to either an intervention or a control group. The intervention group will get routine pain treatment plus pre‐mixed nitrous oxide/oxygen mixture treatment and the control group will be treated with routine pain management plus medical air treatment. All these patients, medical staff and investigators are blind to the nature of the gas in each cylinder, which is randomized. Data will be collected at baseline (T0), 5 min (T1) after the starting of intervention and 5 min post intervention (T2) for each group. The primary outcome is the level of pain relief at T1 and T2. The secondary outcomes cover physiological parameters, adverse events, satisfaction of patients and health professionals and the acceptance from patients.
Discussion
Results of this study will be discussed and the safety and effect of nitrous oxide/oxygen treatment of pain induced by dressing change will be proven.
Impact
When the finding of this study has an active effect on the treatment of pain caused by dressing change, it may provide more options for nursing staff to choose nurse‐led analgesia techniques and then improving the level and quality of pain care as well as patients’ overall satisfaction with the Anorectal Department in China.
摘要
目的
本研究旨在评估肛周脓肿术后换药引起疼痛时的预混合一氧化二氮/氧气混合物治疗的安全性和镇痛效果。
设计
该方案是一项随机、双盲、安慰剂对照试验。
方法
本研究将在中医医院实施。本研究的受试者是因切开引流后换药而引起中度至重度疼痛的住院患者。共计200名患者,这些患者将被随机分配到干预组或对照组。干预组接受常规疼痛治疗加上预混合一氧化二氮/氧气混合物治疗,而对照组主要接受常规疼痛治疗和医用气体治疗。所有患者、医务人员和调查人员都不清楚气瓶中气体的性质,并且,这些气瓶都是随机分配。应分别在基线(T0)、干预开始后5分钟(T1)和干预结束后5分钟(T2)收集数据。主要疼痛缓解结果见T1和T2。次要结果包括生理参数、不良事件、患者和卫生专业人员的满意度以及患者的接受程度等。
讨论
将讨论这项研究的结果,并对一氧化二氮/氧气治疗换药引起的疼痛的安全性和效果进行证明。
影响
如果本研究的调查结果显示,治疗过程中,换药引起的疼痛可带来积极影响,则可为护理人员选择镇痛技术,并且所选择的阵痛技术将由护士主导,从而提高我国肛肠科疼痛护理的水平和质量,提高患者的整体满意度,并可为患者提供更多选择。
Necroptosis is an alternative form of programmed cell death that generally occurs under apoptosis‐deficient conditions. Our previous work showed that connexin32 (Cx32) promotes the malignant progress ...of hepatocellular carcinoma (HCC) by enhancing the ability of resisting apoptosis in vivo and in vitro. Whether triggering necroptosis is a promising strategy to eliminate the apoptosis‐resistant HCC cells with high Cx32 expression remains unknown. In this study, we found that Cx32 expression was positively correlated with the expression of necroptosis protein biomarkers in human HCC specimens, cell lines, and a xenograft model. Treatment with shikonin, a well‐used necroptosis inducer, markedly caused necroptosis in HCC cells. Interestingly, overexpressed Cx32 exacerbated shikonin‐induced necroptosis, but downregulation of Cx32 alleviated necroptosis in vitro and in vivo. Mechanistically, Cx32 was found to bind to Src and promote Src‐mediated caspase 8 phosphorylation and inactivation, which ultimately reduced the activated caspase 8‐mediated proteolysis of receptor‐interacting serine‐threonine protein kinase 1/3, the key molecule for necroptosis activation. In conclusion, we showed that Cx32 contributed to the activation of necroptosis in HCC cells through binding to Src and then mediating the inactivation of caspase 8. The present study suggested that necroptosis inducers could be more favorable than apoptosis inducers to eliminate HCC cells with high expression of Cx32.
Connexin32 promotes shikonin‐induced necroptosis in hepatocellular carcinoma by interacting with Src and enhancing Src‐mediated caspase 8 phosphorylation on Tyr380. We identified the novel role of connexin32 in necroptosis and elucidated connexin32 as a potential target for pronecroptosis therapy in hepatocellular carcinoma.
•This is the first study to study network structure of anxiety-depression in Chinese nursing students.•Irritability, uncontrollable worry, trouble relaxing, and depressed mood constituted central ...symptoms in the network structure of anxiety-depression of nursing students.•Depressed mood, Nervousness, and anhedonia were bridge symptoms of the anxiety-depression network.•Systemic multi-level interventions targeting central symptoms and bridge symptoms may be effective in alleviating overall levels of anxiety and depression in nursing students.
Background: The 2019 coronavirus disease (COVID-19) pandemic has impacted the mental health and well-being of medical personnel, including nursing students. Network analysis provides a deeper characterization of symptom-symptom interactions in mental disorders. The aim of this study was to elucidate characteristics of anxiety and depressive symptom networks of Chinese nursing students during the COVID-19 pandemic.
Method: A total of 932 nursing students were included. Anxiety and depressive symptom were measured using the seven-item Generalized Anxiety Disorder Scale (GAD-7) and two-item Patient Health Questionnaire (PHQ-2), respectively. Central symptoms and bridge symptoms were identified via centrality indices and bridge centrality indices, respectively. Network stability was examined using the case-dropping procedure.
Results: Irritability, Uncontrollable worry, Trouble relaxing, and Depressed mood had the highest centrality values. Three bridge symptoms (Depressed mood, Nervousness, and Anhedonia) were also identified. Neither gender nor region of residence was associated with network global strength, distribution of edge weights or individual edge weights.
Limitations: Data were collected in a cross-sectional study design, therefore, causal relations and dynamic changes between anxiety and depressive symptoms over time could not be inferred. Generalizability of findings may be limited to Chinese nursing students during a particular phase of the current pandemic.
Conclusions: Irritability, Uncontrollable worry, Trouble relaxing, and Depressed mood constituted central symptoms maintaining the anxiety-depression network structure of Chinese nursing students during the pandemic. Timely, systemic multi-level interventions targeting central symptoms and bridge symptoms may be effective in alleviating co-occurring experiences of anxiety and depression in this population.
Background and Objectives
The prevalence of problematic Internet use (PIU) in the post‐COVID‐19 pandemic era is not known. This cross‐sectional study aimed to determine the prevalence of PIU among ...baccalaureate nursing students (hereafter: nursing students) in the post‐COVID‐19 era.
Methods
A total of 1070 nursing students were consecutively invited to participate in this study from the nursing schools of five universities. PIU and quality of life (QOL) were assessed using the Internet Addiction Test (IAT) and the World Health Organization Quality of Life Scale Brief Version (WHOQOL‐BREF), respectively. t Tests, χ2, tests, and Kruskal–Wallis tests were used to compare basic demographic and clinical characteristics between participants with and without PIU. Binary logistic regression analysis was used to examine independent correlates.
Results
The prevalence of PIU was 23.3% (95% confidence interval CI: 20.7%–25.8%). Multiple logistic regression analysis revealed that second‐ (p = .024) and third‐year (p = .012) students were more likely to suffer from PIU compared with first year students. Students with more severe depressive (p = .014) and anxiety symptoms (p = .011) were independently and significantly associated with more severe PIU. After controlling for covariates, nursing students with PIU had a lower overall QOL score (p = .002).
Conclusion and Scientific Significance
Problematic Internet use (PIU) was common among nursing students in the post‐COVID‐19 era. Considering the negative impact of PIU on QOL and academic performance, regular screening should be conducted and effective interventions implemented for nursing students with PIU. This was the first study on the prevalence of PIU among nursing students in the post‐COVID‐19 era. The findings of this study could help health professionals and education authorities to understand the patterns of PIU and its influence on QOL among nursing students and to allocate health resources and develop effective measures to reduce the risk of PIU in this population.
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