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Psychiatric advance directives:privilege,inequity and the path toward justice in psychiatry
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作者 Trae Stewart 《General Psychiatry》 2025年第5期403-408,共6页
Psychiatric advance directives(PADs)represent a significant stride towards self-determination in mental healthcare.These legal documents allow individuals with mental illness to articulate their treatment preferences ... Psychiatric advance directives(PADs)represent a significant stride towards self-determination in mental healthcare.These legal documents allow individuals with mental illness to articulate their treatment preferences for future psychiatric crises when decision-making capacity may be impaired.Designed to empower individuals and reduce coercive interventions,PADs hold the poten-tial to transform patient-clinician dynamics. 展开更多
关键词 mental healthcare patient clinician dynamics coercive interventions psychiatric advance directives psychiatric advance directives pads represent JUSTICE self determination decision making capacity
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The Effect of Educational Intervention regarding Advance Care Planning for Advance Directives
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作者 Yae Takeshita Mika Ikeda +1 位作者 Sayaka Sone Michiko Moriyama 《Health》 2015年第8期934-945,共12页
This study aimed to examine the effects of empowerment and education intervention to promote Advance Care Planning (ACP) for residents in a highly aged and depopulated region. The study utilized a single-group pre- an... This study aimed to examine the effects of empowerment and education intervention to promote Advance Care Planning (ACP) for residents in a highly aged and depopulated region. The study utilized a single-group pre- and post-test design and was conducted in Osakikamijima, Hiroshima, Japan. The researchers and town officials together formed an ACP committee and created an intervention framework. An ACP workshop was held for the participants and a self-administered questionnaire was carried out before, immediately after, and 3 months after the workshop. A total of 125 residents participated in the workshop and 87 of them completed more than 80% of the questionnaire items, whose responses were analyzed as valid responses. The number of participants who completed the AD increased significantly three months after the workshop (p = 0.008). There was a slight increase in the frequency of consultation with the family, but no change was observed in terms of consultation with healthcare providers. The educational intervention in-creased the respondents’ awareness and knowledge of ACP but did not affect the autonomous decision-making process regarding end-of-life care. This strategic process of ACP empowered the residents’ awareness and attitude towards end-of-life care with an increased completion rate of AD. On the other hand, cognitive barriers remained toward communication and decision-making shared with healthcare providers. Insufficient consultation with family members also became evident. Therefore, a new intervention strategy which helps increase communication with healthcare providers needs to be formulated and guidelines for consultation with the family and others need to be prepared. 展开更多
关键词 END-OF-LIFE ADVANCE CARE Planning ADVANCE directives COMMUNITY EMPOWERMENT
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Advance Directives in the Context of Uncertain Prognosis for Residents of Nursing Homes
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作者 Beryl E. Cable-Williams Donna M. Donna M. Wilson Norah Keating 《Open Journal of Nursing》 2014年第4期321-329,共9页
This report documents the findings of a mixed-methods study focused on the advanced directives of 182 residents of three LTC facilities in southern Ontario, Canada. Although almost all had a completed advance directiv... This report documents the findings of a mixed-methods study focused on the advanced directives of 182 residents of three LTC facilities in southern Ontario, Canada. Although almost all had a completed advance directive within 3 months of death, most did not have a palliative designation or directive until a few days before they died. Each facility’s written Progress Notes revealed staff members usually sought additional confirmation of care preferences from residents’ substitute decision-makers within a few days of the death. It was thus common for advance directives to change from a more interventionist approach to the least interventionist approach near death. This change indicates that the meaning and significance of advance care planning and resulting advance directives must be considered in light of the processes and temporal factors involved in their completion and use within this distinct population. The relational nature of advance care planning and concern about ageism as a factor for withholding or withdrawing life support for LTC residents are considered as possible explanatory factors. These findings and their implications are described in relation to end-of-life care policies and practices in LTC facilities. 展开更多
关键词 ADVANCE CARE Planning ADVANCE directives PALLIATIVE CARE Nursing HOMES
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Assessment of a Multimodal Strategy for Information and Collection of Advance Directives in a Comprehensive Cancer Center:Description of the Study Protocol
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作者 Léonor Fasse François Blot 《Psycho-Oncologie》 SCIE 2024年第4期367-375,共9页
Background:Information on the possibility of drawing up Advance Directives(AD)is a necessity,and represents a major medical,ethical,and legal challenge.The difficulties are numerous,both organizational and cultural,an... Background:Information on the possibility of drawing up Advance Directives(AD)is a necessity,and represents a major medical,ethical,and legal challenge.The difficulties are numerous,both organizational and cultural,and this is also true in the context of oncology,where ADs(and more broadly,advanced palliative care)are of critical importance.As an eminently sensitive subject,dealing with ADs(and therefore with end-of-life issues)requires both societal and medical/health-care acculturation.An institutional approach has therefore been developed,to deploy information tools,training professionals,and formalize the collection of AD.Such an approach cannot be implemented without an assessment not only of its objective results but also above all of its psychological effects,on both users(patients,family caregivers)and professionals.Methods:This longitudinal study,based on a mixed-method,interdisciplinary approach,will assess the impact of this information dissemination on AD,in terms of both potential positive and negative effects,using validated measurement methods.Thus,this study follows the 5 criteria of the RE-AIM model,designed to analyze the interest and impact of a device intended for users of the healthcare system;we will use a mixed methodology,relying on both a quantitative component(counting the number of people benefiting from the scheme,and those requesting support in drawing up their DA...,administering questionnaires),as well as a qualitative component(focus groups)which will enable us to study the subjective experiences of users,their relatives and the professionals involved in the scheme.Results:The results of this study will make it possible to determine the effects of this system of assistance in the drafting of ADs,which is currently being promoted by the legislator,but which is struggling to be implemented. 展开更多
关键词 Advance directive CANCER palliative care living wills end of life shared-decision making
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Directives and references in selected coronavirus-motivated internet memes 被引量:2
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作者 Ayo Osisanwo Toluwalope Mary Falade 《Language and Semiotic Studies》 2024年第2期245-266,共22页
The use of directives in communicating the nature of the pandemic and reference to social experiences were promoted using images on social media platforms.The images or memes are used to create awareness and reinforce... The use of directives in communicating the nature of the pandemic and reference to social experiences were promoted using images on social media platforms.The images or memes are used to create awareness and reinforce the criteria for safety during the pandemic.Previous studies on internet memes have concentrated on humor generation,speaker-hearer shared knowledge,neologism,and multimodality among others,with insufficient attention paid to the use of directives and references in such coronavirus-motivated memes.This paper,therefore,examines how directives and references are employed in conveying expected social responsibilities through coronavirus-motivated internet memes in Nigeria and other socio-cultural contexts.For data,one hundred coronavirus-motivated memes were purposively selected from Facebook,and eight representative memes were subjected to pragmatic analysis using aspects of Jacob Mey’s(2001.Pragmatics:An introduction,2nd edn.USA:Blackwell Publishing)pragmatic acts theory to unearth insights from them.The paper observes that the various spheres of life that are relatable to an online audience help to express what the pandemic is about and enhance the meaning of the pandemic with the context of the use of the memes,giving clearer perspectives on the pandemic.Directives and references are useful tools for conveying social responsibilities to online audience. 展开更多
关键词 directives REFERENCES CORONAVIRUS internet memes social responsibilities
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S-scheme unidirectional transmission of CdS-CuO heterojunction benefits for superior photocatalytic hydrogen evolution efficiency
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作者 ZHAO Haiting YAN Zheng +2 位作者 LIU Yang JIANG Longde LUAN Jingde 《燃料化学学报(中英文)》 北大核心 2026年第1期1-14,共14页
The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ... The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion. 展开更多
关键词 photocatalytic hydrogen evolution CdS-CuO S-scheme heterojunction electron directional transmission interfacial electric field DFT calculation
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Effect of Cyclic Heat Treatment on Fatigue Crack Growth Rate of Ti-6Al-4V-1Mo Alloy Prepared by Laser Directed Energy Deposition
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作者 Xue Lipan Zhang Fengying +6 位作者 Deng Yulin Ye Zimeng Zhao Kexin Yu Zerong Wu Wenlu Su Wei Yang Renjie 《稀有金属材料与工程》 北大核心 2026年第2期292-301,共10页
The fatigue crack growth rate of a novel Ti-6Al-4V-1Mo titanium alloy,which is developed for laser directed energy deposition technique,was investigated before and after cyclic heat treatment(CHT).Changes in microstru... The fatigue crack growth rate of a novel Ti-6Al-4V-1Mo titanium alloy,which is developed for laser directed energy deposition technique,was investigated before and after cyclic heat treatment(CHT).Changes in microstructure,fracture surfaces,and crack growth paths were analyzed before and after CHT.Results indicate that in the stable crack growth region,the growth rates for the as-deposited and cyclic heat-treated specimens follow the relationships da/dN=1.8651×10^(−8)(ΔK)^(3.2271)and da/dN=1.4112×10^(−8)(ΔK)^(3.1125),respectively.Compared with that at the as-deposited state,the microstructure after CHT is transformed from a uniform basket-weave microstructure to a dual-phase microstructure consisting of near-sphericalαandβ-transformed matrix phases.The cyclic process also disrupts the continuity of the grain boundaryα(αGB)at the primaryβ-phase grain boundary.The coarsening of primaryαand the disruption ofαGB continuity are the primary factors to release stress concentration and promote crack deflection,thereby decreasing the fatigue crack growth rate.Additionally,the increased occurrence of crack branching,secondary cracking,and crack bridging in cyclic heat-treated specimens further reduces the crack driving force and slows the fatigue crack growth rate. 展开更多
关键词 Ti-6Al-4V-1Mo alloy CHT fatigue crack growth rate laser directed energy deposition
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基于增强时空平滑算法的相干信号DOA估计
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作者 窦慧晶 路瑶 +1 位作者 张雨欣 刘胜浩 《北京工业大学学报》 北大核心 2026年第1期55-63,共9页
在相干信号波达方向(direction of arrival,DOA)估计中,当阵列接收到的相干信号处于低信噪比时,DOA估计性能会大大降低。针对该问题,提出一种增强的时空平滑(enhanced spatio-temporal smoothing,ESTS)算法,在使用时空相关矩阵重构接收... 在相干信号波达方向(direction of arrival,DOA)估计中,当阵列接收到的相干信号处于低信噪比时,DOA估计性能会大大降低。针对该问题,提出一种增强的时空平滑(enhanced spatio-temporal smoothing,ESTS)算法,在使用时空相关矩阵重构接收数据矩阵的时空平滑(spatio-temporal smoothing,STS)方法的基础上进行了改进。首先对子阵列时空相关矩阵进行平方预处理,然后通过充分利用子阵列时空相关矩阵的协方差和互协方差信息解相干,提高了相干信号的分辨率以及对噪声扰动的鲁棒性。理论分析和统计结果均表明,与其他空间平滑类解相干方法相比,该方法提高了在低信噪比、少快拍数、小角度分离情况下的相干信号DOA估计的去相关性能。 展开更多
关键词 波达方向(direction of arrival DOA)估计 相干信号 空间平滑 时空相关矩阵 互相关 分辨率
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Directional Three‑Dimensional Macroporous Carbon Foams Decorated with WC_(1−x)Nanoparticles Derived from Salting‑Out Protein Assemblies for Highly Effective Electromagnetic Absorption
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作者 Yongzheng Chen Lixue Gai +5 位作者 Bo Hu Yan Wang Yanyi Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 2026年第3期1-21,共21页
Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usu... Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components. 展开更多
关键词 3D macroporous carbon-based foams Directional pore channels Salting-out protein assemblies EM wave absorption Directional dependence
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Comprehensive insights into the organic/inorganic composition separation of sewer sediment by various driving forces:Separation pathway and thermodynamic evolution
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作者 Heliang Pang Jiangbo Ding +3 位作者 Yan Wang Jiawei Liu Qiwen Qin Jinsuo Lu 《Journal of Environmental Sciences》 2026年第1期785-796,共12页
With the legislative development,the organic and inorganic composition separation has become the primary requirement for sewer sediment disposal,however the relevant technology has been rarely reported and the driving... With the legislative development,the organic and inorganic composition separation has become the primary requirement for sewer sediment disposal,however the relevant technology has been rarely reported and the driving mechanism was still unclear.In this study,direct disintegration of biopolymers and indirect broken of connection point were investigated on the hydrolysis and component separation.Three typical sewer sediment treatment approaches,i.e.,alkaline,thermal and cation exchange treatments were proposed,which represented the hydrolysis-driving forces of chemical hydrolysis,physical hydrolysis and innovative cation bridging break-age.The results showed that the organic and inorganic separation rates of sewer sediment driven by alkaline,thermal and cation exchange treatments reached 21.26%,23.80%,and 19.56%-48.0%,respectively,compared to 4.43%in control.The secondary structure of proteins was disrupted,transitioning from𝛼α-helix to𝛽β-turn and random coil.Meanwhile,much biopolymers were released from solid to the liquid phase.From thermody-namic perspective,sewer sediment deposition was controlled by short-range interfacial interactions described by extended Derjaguin-Landau-Verwey-Overbeek theory.Additionally,the separation of organic and inorganic components was positively correlated with the thermodynamic parameters(Corr=0.87),highlighted the robust-ness of various driving forces.And the flocculation energy barriers were 2.40(alkaline),1.60 times(thermal),and 4.02–4.97 times(cation exchange)compared to control group.The findings revealed the contrition differ-ence of direct disintegration of gelatinous biopolymers and indirect breakage of composition connection sites in sediment composition separation,filling the critical gaps in understanding the specific mechanisms of sediment biopolymer disintegration and intermolecular connection breakage. 展开更多
关键词 Sewer sediment Component separation Directly disintegration Indirect broken Thermodynamic Biopolymer
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Studies of directed flow with event plane method in the HIRFL-CSR external-target experiment
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作者 Wan-Long Wu Xiong-Hong He +3 位作者 Yan-Yu Ren Di-Yu Shen Shu-Su Shi Xu Sun 《Nuclear Science and Techniques》 2026年第4期19-27,共9页
The Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL)is designed to study the properties of nuclear matter created in heavy-ion collisions at beam energies from a... The Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL)is designed to study the properties of nuclear matter created in heavy-ion collisions at beam energies from a few hundred MeV/u up to 1 GeV/u.It aims to facilitate research on the quantum chromodynamics(QCD)phase structure in the high-baryondensity region.Collective flow is a fundamental observable in heavy-ion collision experiments,providing information on the bulk properties of the produced matter.Although the standard event plane method has been widely used to measure collective flow,it is still important to validate and optimize this method for the CEE spectrometer.In this paper,we study the experimental procedures for measuring directed flow in^(238)U+^(238)U collisions at 500 MeV/u,using event planes reconstructed by Multi-Wire Drift Chamber and Zero Degree Calorimeter,respectively.Jet AA Microscopic(JAM)transport generator is used to generate events,and the detector response is simulated by the CEE Fast Simulation(CFS)package.Finally,the optimal kinematic region for proton directed flow measurements is discussed for the future CEE experiment. 展开更多
关键词 Heavy-ion collisions CEE Directed flow Event plane
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Advanced direct recycling enables upcycling of spent lithium-ion batteries
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作者 Wei Liu Linfeng Peng +2 位作者 Ziqi Zeng Shijie Cheng Jia Xie 《Science China Chemistry》 2026年第2期619-639,共21页
The rapid expansion of lithium-ion batteries in electric vehicles and grid-scale energy storage intensify the demand for sustainable recycling strategies.Traditional metallurgical recycling methods face significant ch... The rapid expansion of lithium-ion batteries in electric vehicles and grid-scale energy storage intensify the demand for sustainable recycling strategies.Traditional metallurgical recycling methods face significant challenges,including high energy consumption,environmental pollution,and inefficient critical metals recovery.In contrast,advanced direct recycling can selectively extract valuable metals while preserving cathode structure,achieving over 99%lithium recovery from lithium iron phosphate.Moreover,by directly repairing defects and crystal structures of spent materials,their electrochemical performance can be effectively restored.Due to significantly reduced energy and reagent inputs,direct recycling cuts processing costs by over 20% and reduces waste emissions by at least 40% compared to conventional methods,making it a promising low-carbon alternative.This review systematically integrates the recent advances in direct recycling of spent batteries as well as the limitations and challenges of existing technologies,and proposes future research pathways to promote resource recycling and sustainable development. 展开更多
关键词 lithium-ion battery spent cathode direct recycling metal recovery SUSTAINABILITY
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Interventional Room Nursing for Patients with Ischemic Stroke Treated with Tirofiban Combined with Direct Thrombectomy
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作者 Yayun Xiong 《Journal of Clinical and Nursing Research》 2026年第1期214-220,共7页
Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic s... Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic stroke admitted to our hospital from June 2024 to June 2025 were selected and divided into two groups using the red and blue ball method:the control group(n=30,receiving routine interventional room nursing)and the observation group(n=31,receiving additional tirofiban medication-specific nursing+individualized interventional nursing on the basis of routine nursing).The cerebral hemodynamic indicators,adverse reactions,effectiveness of complication nursing,and nursing satisfaction were compared between the two groups.Results:After 7 days of treatment,the observation group had lower cerebrovascular peripheral resistance and higher mean blood flow velocity and mean blood flow volume compared to the control group(all p<0.05).The observation group had a higher effectiveness rate of complication nursing than the control group,with a statistically significant difference(p<0.05).The nursing satisfaction in the observation group(96.77%)was higher than that in the control group(80.00%),with a statistically significant difference(χ^(2)=4.223,p=0.040<0.05).Conclusion:Tirofiban combined with direct thrombectomy can significantly improve cerebral hemodynamics,enhance the effectiveness of complication nursing,and increase patient satisfaction in patients with ischemic stroke. 展开更多
关键词 Tirofiban Direct thrombectomy Ischemic stroke Interventional room nursing Nursing coordination
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 Patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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A core-shell type Co_(19)-added polyoxometalate for visible-light-driven photocatalytic hydrogen evolution
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作者 Zhen-Wen Wang Guo-Yu Yang 《Science China Chemistry》 2026年第2期737-741,共5页
A core-shell type Co_(19)-added polyoxometalate H_(17)Na_(4)Cs_(21)[Co_(19)(μ_(3)-OH)_(12)(A-α-SiW_(10)O_(37))_(6)]·8 Cl·12H_(2)O(1)has been made under hydrothermal conditions guided by the lacunary direct... A core-shell type Co_(19)-added polyoxometalate H_(17)Na_(4)Cs_(21)[Co_(19)(μ_(3)-OH)_(12)(A-α-SiW_(10)O_(37))_(6)]·8 Cl·12H_(2)O(1)has been made under hydrothermal conditions guided by the lacunary directing synthetic strategy.Single crystal X-ray diffraction(SXRD)has shown that 19 Co^(2+)are arranged in a flat plane through edge sharing in a mode of 3-4-5-4-3,forming a core-shell type polyanion cluster{Co_(19)(SiW_(10))_6}with a diameter of approximately 2.24 nm.Visible-light-driven photocatalytic hydrogen evolution performance studies have shown that 1 is an efficient heterogeneous water reduction catalyst(WRC)with the H_(2)evolution rate of 2902.5μmol h^(-1)g^(-1).Moreover,the cycle tests indicated that 1 was also a good heterogeneous catalyst. 展开更多
关键词 POLYOXOMETALATES visible-light-driven hydrogen evolution lacunary directing synthesis hydrothermal synthesis cobalt
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Femtosecond Laser Direct Writing of Biopolymeric Nanocomposite for Biocompatible 3D Features
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作者 Feng Jin Xian-Zi Dong +1 位作者 Jie Liu Mei-Ling Zheng 《Chinese Journal of Polymer Science》 2026年第2期465-473,I0014,共10页
Biopolymeric nanocomposites have attracted considerable attention because of their biocompatibility,biodegradability,and unique physicochemical properties.It is essential to manufacture three-dimensional(3D)biocompati... Biopolymeric nanocomposites have attracted considerable attention because of their biocompatibility,biodegradability,and unique physicochemical properties.It is essential to manufacture three-dimensional(3D)biocompatible micro/nanostructures using biopolymeric nanocomposites.Herein,we demonstrate the high-fidelity fabrication of biocompatible 3D features with sub-50 nm resolution using femtosecond laser direct writing(FsLDW)of a biopolymeric nanocomposite composed of egg white and sulfonated graphene(S-graphene).The biopolymer nanocomposite acts as a negative photoresist suitable for water-based lithography.The introduction of S-graphene not only dramatically lowered the laser power threshold but also significantly modulated the morphology of the 3D features constructed by FsLDW.Microstructures with porous,rough,or smooth morphologies were obtained by optimizing the S-graphene concentration and laser scanning speed.The fabricated egg-white/S-graphene microstructures exhibited biocompatibility and environmental degradability.Egg white/S-graphene was also employed to fabricate diffractive gratings with superior optical quality.This study provides a promising method to manufacture biocompatible 3D features with controllable morphology,which has potential applications in biological and photonic fields. 展开更多
关键词 Femtosecond laser direct writing Biopolymeric nanocomposite Egg white Sulfonated graphene PHOTORESIST
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Magnetic fabric of the late Miocene extrusive rocks of the Combia Volcanic Province:Tectonic implications for the northern Andes
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作者 Victor A.Piedrahita Martin Chadima +3 位作者 Jackeline Ramírez Alejandra Tabares Maria I.Marín-Cerón JinHua Li 《Earth and Planetary Physics》 2026年第1期44-56,共13页
The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-m... The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-middle Miocene deformed rocks of the inter-Andean valley between the Western and Central Cordilleras of Colombia.However,uncertainty remains about the age of the latest accretionary phases of the Panama-ChocóBlock.Poorly studied late Miocene volcanic rocks within the northern inter-Andean valley may provide key information to constrain the temporality of that final collision.Here,we study the deformational features of the~12-6 Ma extrusive rocks of the Combia Volcanic Province located in the northwestern Andes(Colombia).We present anisotropy of magnetic susceptibility(AMS)data for pyroclastic and volcanic rocks within the AmagáBasin,an inter-Andean depression with Oligocene-middle Miocene sedimentary rocks that recorded NW-SE compression and NE-SW simple shear caused by the Panama-ChocóBlock collision.We identified that the magnetic fabrics of the extrusive rocks of the Combia Volcanic Province reveal flow directions that indicate the occurrence of ancient volcanoes in the central axis of the AmagáBasin.Some of these fabrics do not contain any deformational features,whereas others record the same structural regime as the Oligocene-middle Miocene sedimentary rocks.We infer that variations in the intensity of the deformation promoted late Miocene local fault reactivations that,in contrast to the Oligocene-middle Miocene deformational events,did not affect the entire AmagáBasin.Age differences among the studied sections can also explain the different deformational patterns identified in the basin.Both interpretations suggest that the most significant collisional events of the Panama-ChocóBlock occurred in the Oligocene-middle Miocene,whereas the formation of the Combia Volcanic Province may have either followed or coincided with the latest stages of the accretion. 展开更多
关键词 Combia Volcanic Province Panama-ChocóBlock magnetic fabric deformation flow direction
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Multi-frequency non-reciprocal optical directional amplifier realized with non-Hermitian resonator arrays
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作者 Jin-Xiang Xue Chuan-Xun Du +2 位作者 Cheng-Chao Liu Liu Yang Yong-Long Wang 《Chinese Physics B》 2026年第2期423-432,共10页
For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add c... For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add channels to the non-reciprocal optical device and the non-reciprocity can route optical signals and prevent the reverse flow of noise.Using the Scully–Lamb model and gain saturation effect,we accomplish dual-frequency non-reciprocal transmission by introducing nonlinearity into a linear array of four-mode resonators.The accomplishment is directly demonstrated by the non-reciprocal transmission phenomena present in the non-divergent peaks.For example,a directional cyclic amplifier is constructed with non-reciprocal units.Regarding potential applications,non-reciprocal optical systems can be employed in dual-frequency control,parallel information processing,photonic integrated circuits,optical devices and so on. 展开更多
关键词 non-Hermitian systems PT-SYMMETRY multi-frequency of non-reciprocity optical directional amplifier
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IOTA-Based Authentication for IoT Devices in Satellite Networks
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作者 D.Bernal O.Ledesma +1 位作者 P.Lamo J.Bermejo 《Computers, Materials & Continua》 2026年第1期1885-1923,共39页
This work evaluates an architecture for decentralized authentication of Internet of Things(IoT)devices in Low Earth Orbit(LEO)satellite networks using IOTA Identity technology.To the best of our knowledge,it is the fi... This work evaluates an architecture for decentralized authentication of Internet of Things(IoT)devices in Low Earth Orbit(LEO)satellite networks using IOTA Identity technology.To the best of our knowledge,it is the first proposal to integrate IOTA’s Directed Acyclic Graph(DAG)-based identity framework into satellite IoT environments,enabling lightweight and distributed authentication under intermittent connectivity.The system leverages Decentralized Identifiers(DIDs)and Verifiable Credentials(VCs)over the Tangle,eliminating the need for mining and sequential blocks.An identity management workflow is implemented that supports the creation,validation,deactivation,and reactivation of IoT devices,and is experimentally validated on the Shimmer Testnet.Three metrics are defined and measured:resolution time,deactivation time,and reactivation time.To improve robustness,an algorithmic optimization is introduced that minimizes communication overhead and reduces latency during deactivation.The experimental results are compared with orbital simulations of satellite revisit times to assess operational feasibility.Unlike blockchain-based approaches,which typically suffer from high confirmation delays and scalability constraints,the proposed DAG architecture provides fast,cost-free operations suitable for resource-constrained IoT devices.The results show that authentication can be efficiently performed within satellite connectivity windows,positioning IOTA Identity as a viable solution for secure and scalable IoT authentication in LEO satellite networks. 展开更多
关键词 Satellite IoT decentralized authentication directed acyclic graph IOTA identity verifiable credentials
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Vacuum-ultraviolet technology photolysis of aqueous reaction systems for organic pollutants abatement
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作者 Bing Zhang Guoqing Jiang +2 位作者 Wenxin Shi Yanei Xue Wenjun Sun 《Chinese Chemical Letters》 2026年第2期263-273,共11页
Vacuum-ultraviolet(VUV)radiation is high-energy UV radiation with a wavelength of 100-200 nm capable of decomposing/mineralizing hazardous emerging organic pollutants(EPs)in water through direct photolysis and/or by g... Vacuum-ultraviolet(VUV)radiation is high-energy UV radiation with a wavelength of 100-200 nm capable of decomposing/mineralizing hazardous emerging organic pollutants(EPs)in water through direct photolysis and/or by generating reactive free radicals(RFRs)during photolysis.However,due to the unsatisfactory photoelectric conversion rate,strong absorption by oxygen and water molecules,and other characteristics of VUV radiation,its application and development are hindered,leading to misconceptions regarding high energy consumption and insufficient free radical yield.The objectives of our assessment in this review are as follows:The illumination of the photochemical characteristics of VUV and the reactivity of aqueous solutions.Summarization of accurate UV dose and energy evaluation criteria.Comparison and analysis of the photochemical mechanisms and reaction kinetics of different types of EPs via VUV direct photolysis,as well as the interference origins of typical substrates in water for VUV decontamination.We found that quantities typically reported in VUV photochemical reactions of engineered systems are underreported in low-pressure mercury lamp(LPUV)photochemical reactions,especially a quantitative indicator of the species or energy that induces a chemical reaction.The absence of these quantities has made it difficult to assess the fundamental performance of VUV photolysis fully compared with that of UV-C.Some studies have sought to optimize VUV-advanced reduction processes(VUV-ARP)or VUV reactor treatment of these contaminants;however,an abundant evaluation of the reaction origins and processes between VUV-derived main RFRs and reactants(H_(2)O,O_(2),organic matter,inorganic ions,etc.)is essential,cause these scientific elements will provide the possibility to break the application gap for VUV in the field of EPs treating.Overall,the data compilation,analysis,and research recommendations provided in this review will form the basis for all photochemical reactions initiated by VUV radiation with water as the backing agent. 展开更多
关键词 VACUUM-ULTRAVIOLET Reactive free radicals UV dose Advanced reduction processes Direct photolysis
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