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Polymerization of 1,3-Butadiene with Catalysts Based on Cobalt Dichloride Complexes with Aminophosphines: Switching the Regioselectivity by Varying the MAO/Co Molar Ratio

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Chinese Journal of Polymer Science 2024年第4期42卷 501-510页

作者： Giovanni Ricci Anna Sommazzi Francesco Masi alessandra Forni CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via A.Corti 1220133MilanoItaly Viale Giovanni XXIII 34 I-28100NovaraNOItaly Via Galvani 7 I-26866Sant’Angelo LodigianoLOItaly CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via C.Golgi 1920133MilanoItaly

Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and *** some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction *** the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar *** behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.

关键词： 1,3-Butadiene Stereospecific polymerization Cobalt catalysts Regioselectivity Aminophosphine ligands Crystal structures Chelate rings

A Methodology for Vulnerability Assessment of Cultural Heritage in Extreme Climate Changes

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International Journal of Disaster Risk Science 2024年第3期15卷 404-420页

作者： Riccardo Cacciotti Alessandro Sardella Milo? Drdácky alessandra Bonazza Institute of Theoretical and Applied Mechanics Czech Academy of Sciences Institute of Atmospheric Sciences and Climate National Research Council of Italy Department of Environmental and Prevention Sciences University of Ferrara Istituto Superiore per la Protezione e la Ricerca Ambientale

Vulnerability evaluation plays a key role in risk assessment and reduction and is essential for defining strategies for climate change adaptation and mitigation. In dealing with the safeguarding of cultural heritage at risk, we are still far from adopting and applying an agreed methodology for vulnerability assessment. With the aim to support practitioners, heritage managers,and policy and decision makers to undertake actions that address the protection of cultural heritage at risk, the methodology set up in the framework of the Interreg Central Europe STRENCH is illustrated and discussed here. Based on three major requirements(susceptibility, exposure, and resilience) and a continuous consultation with local stakeholders, the proposed methodology is applicable for evaluating the vulnerability of built heritage and cultural landscape exposed to hydrometeorological hazards, such as heavy rains, floods, and droughts. The results obtained through its validation on 15 case studies from seven Central European regions are shown to underline the strengths and limitations of the methodological *** consultation with local stakeholders was fundamental for the definition of the criteria/subcriteria and related values for the assessment of the requirements. Application to further sites in other contexts would surely contribute to strengthening the reliability of the methodological approach.

关键词： Built and natural heritage Exposure Heritage vulnerability Resilience Risk management Susceptibility

Impact of cattle density on the structure and natural regeneration of a turkey oak stand on an agrosilvopastoral farm in central Italy

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Journal of Forestry Research 2024年第1期35卷 168-182页

作者： alessandra Pacini Francesco Pelleri Francesco Marini Alberto Maltoni Barbara Mariotti Gianluigi Mazza Maria Chiara Manetti Department of Agriculture FoodEnvironmentand ForestryUniversity of Florence50144 FlorenceItaly CREA Research Centre for Forestry and Wood 52100 ArezzoItaly PEFC Programme for the Endorsement of Forest Certification 06135 PerugiaItaly

On an agrosilvopastoral farm in central Italy where Maremmana cattle graze in Turkey oak forests,we evaluated the impact of different livestock densities on stand structure,tree diversity and natural regeneration in four types of grazed areas based on the grazing regime adopted:calf-grazed,high-intensity-grazed,low-intensity-grazed,ungrazed *** each area,we set up three permanent circular plots(radius of 15 m)to survey the structural and dasometric characteristics of the overstorey,understorey,and regeneration *** results showed that grazing negatively affected the complexity of the forest structure and its potential to regenerate and maintain a high level of *** differences in stand structure observed between the grazing areas were closely related to livestock *** most sensitive components of the system were the understorey and the regeneration ***,the current grazing management did not affect the dominant tree structure or its *** findings identified medium-term monitoring and regeneration management as the two significant aspects to consider when assessing sustainable *** forests can be established by excluding graz-ing for about 20–25 years.

关键词： Agroforestry Stand structure Regeneration Tree biodiversity Grazing intensity

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人工智能面临的复杂性挑战

自然辩证法研究 2024年第6期40卷 72-77页

作者：任然 Francesco Di iorio 南开大学哲学院天津300350

随着近年来人工智能和复杂性科学的发展,复杂性挑战不仅延续到智能系统中,而且围绕着计算复杂性问题展开。生成式人工智能的兴起彻底颠覆了以往对复杂性问题的认知,不仅涉及智能系统的复杂性,而且涉及自然系统的复杂性,探讨了许多新的问... 详细信息

随着近年来人工智能和复杂性科学的发展,复杂性挑战不仅延续到智能系统中,而且围绕着计算复杂性问题展开。生成式人工智能的兴起彻底颠覆了以往对复杂性问题的认知,不仅涉及智能系统的复杂性,而且涉及自然系统的复杂性,探讨了许多新的问题,例如如何解决“生成难度”问题,提出了一些应对挑战的方法论原则,例如奥卡姆剃刀原则,深化了我们对有关认识论和方法论问题的思考。

关键词：人工智能计算复杂性生成式人工智能复杂性挑战

Prognosis value of heat-shock proteins in esophageal and esophagogastric cancer:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1578-1595页

作者： Eric Toshiyuki Nakamura Amanda Park Marina alessandra Pereira Daniel Kikawa Francisco Tustumi Department of Gastroenterology Instituto do CâncerHospital das Clínicas da Universidade de São PauloFaculdade de MedicinaUniversidade de São PauloSão Paulo 01246000Brazil Department of Scientific Initiation Universidade Mogi das CruzesSão Paulo 08780911Brazil Department of Evidence-Based Medicine Centro Universitário LusíadaCentre for Evidence-Based MedicineCentro Universitário Lusíada(UNILUS)SantosBrazil Department of Surgery Hospital Israelita Albert EinsteinSão Paulo 05652900Brazil

BACKGROUND Heat shock proteins(HSPs)are molecular chaperones that play an important role in cellular protection against stress events and have been reported to be overex-pressed in many *** prognostic significance of HSPs and their regulatory factors,such as heat shock factor 1(HSF1)and CHIP,are poorly *** To investigate the relationship between HSP expression and prognosis in esophageal and esophagogastric *** A systematic review was conducted in accordance with PRISMA recommend-ations(PROSPERO:CRD42022370653),on Embase,PubMed,Cochrane,and ***,case-control,and cross-sectional studies of patients with eso-phagus or esophagogastric cancer were ***-positive patients were compared with HSP-negative,and the endpoints analyzed were lymph node metastasis,tumor depth,distant metastasis,and overall survival(OS).HSPs were stratified according to the HSP family,and the summary risk difference(RD)was calculated using a random-effect *** The final selection comprised 27 studies,including esophageal squamous cell carcinoma(21),esophagogastric adenocarcinoma(5),and mixed neoplasms(1).The pooled sample size was 3465 ***40 and 60 were associated with a higher 3-year OS[HSP40:RD=0.22;95%confidence interval(CI):0.09-0.35;HSP60:RD=0.33;95%CI:0.17-0.50],while HSF1 was associated with a poor 3-year OS(RD=-0.22;95%CI:-0.32 to-0.12).The other HSP families were not associated with long-term ***1 was associated with a higher probability of lymph node metastasis(RD=-0.16;95%CI:-0.29 to-0.04).HSP40 was associated with a lower probability of lymph node dissemination(RD=0.18;95%CI:0.03-0.33).The expression of other HSP families was not significantly related to tumor depth and lymph node or distant *** The expression levels of certain families of HSP,such as HSP40 and 60 and HSF1,are associated with long-term survival and lymph node dissemination in patients with esophageal and esophagogastric cancer.

关键词： Heat-shock proteins Heat-shock response Prognosis Esophageal neoplasms Meta-analysis

从热力学计算到定形体系的实验表征设计全金属复合相变材料

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Transactions of Nonferrous Metals Society of China 2024年第5期34卷 1393-1412页

作者： Chiara CONFALONIERI alessandra CAMNAGHI Elisabetta GARIBOLDI Politecnico di Milano Department of Mechanical EngineeringVia La Masa 120156 MilanItaly

用于热能管理的复合相变材料(C-PCMs)利用其一个或多个低熔点活性相的可逆相变(如熔化—凝固)存储和释放热能作为潜热。同时,高熔点的惰性相可以提供额外的性能,如定形性和改善的导热性。从难混溶合金中可获得具有这些特征的全金属复合... 详细信息

用于热能管理的复合相变材料(C-PCMs)利用其一个或多个低熔点活性相的可逆相变(如熔化—凝固)存储和释放热能作为潜热。同时,高熔点的惰性相可以提供额外的性能,如定形性和改善的导热性。从难混溶合金中可获得具有这些特征的全金属复合材料体系。本文将热力学计算和实验测试相结合,探讨二元(Al-In,Al-Sn,Al-Bi和Cu-Bi)和三元(Al-In-Sn和Al-Bi-Sn)难混溶合金在100~300℃的温度范围内用作C-PCMs的潜力。结果表明,将这两种方法相结合对于全面理解复合体系和找到满足设计需求的最佳解决方案十分必要,它克服了“试错”法浪费时间的弊端,并为模拟提供了高质量的数据。

关键词：复合相变材料合金设计热力学性能定形性储热

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Phosphodiesterase 9 localization in cytoplasm and nucleus:the gateway to selective targeting in neuroprotection?

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Neural Regeneration Research 2025年第6期20卷 1701-1702页

作者： Giovanni Ribaudo Matteo Giannangeli Margrate Anyanwu alessandra Gianoncelli Department of Molecular and Translational Medicine University of BresciaBresciaItaly

The umbrella term"neurodege ne rative disorders"(NDDs) refers to several conditions characterized by a progressive loss of structure and function of cells belonging to the nervous *** diseases affect more than 50million people *** disorders are characterized by sundry factors and pathophysiological mechanisms that a re challenging to be fully *** of these rely on cell signaling pathways to preserve homeostasis,involving second messengers such as cyclic adenosine monophosphate (cAMP)and cyclic guanosine 3',5'-monophosphate(cGMP).Their ability to control the duration and amplitude of the signaling cascade is given by the presence of several common and uncommon *** kinases A and G (PKA and PKG),phosphodiesterases (PDEs),and scaffold proteins are among them.

关键词： gateway homeostasis preserve

Risk factors for long COVID in children and adolescents:a systematic review and meta-analysis

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World Journal of Pediatrics 2024年第2期20卷 133-142页

作者： Daniel G.Rayner Elaine Wang Cloris Su Om D.Patel Stephanie Aleluya alessandra Giglia Evelyn Zhu Maha Siddique Department of Health Research Methods Evidenceand ImpactFaculty of Health SciencesMcMaster University1280 Main St WHamiltonONL8S 4K1Canada Faculty of Health Sciences McMaster University1280 Main St WHamiltonON L8S 4K1Canada Faculty of Science McMaster University1280 Main St WHamiltonONL8S 4K1Canada

Background The long-term sequelae of COVID-19 in children and adolescents remain poorly understood and *** systematic review and meta-analysis sought to summarize the risk factors for long COVID in the pediatric *** We searched six databases from January 2020 to May 2023 for observational studies reporting on risk factors for long COVID or persistent symptoms those were present 12 or more weeks post-infection using multivariable regression *** registries,reference lists of included studies,and preprint servers were hand-searched for relevant ***-effects meta-analyses were conducted to pool odds ratios for each risk *** study risk of bias was rated using QUIPS,and the GRADE framework was used to assess the certainty of evidence for each unique *** Sixteen observational studies(N=46,262)were included,and 19 risk factors were amenable to *** moderate certainty in the evidence,age(per 2-year increase),allergic rhinitis,obesity,previous respiratory diseases,hospitalization,severe acute COVID-19,and symptomatic acute COVID-19 are probably associated with an increased risk of long *** sex,asthma,comorbidity,and heart diseases may be associated with an increased risk of long COVID,and Asian and Black races may be associated with a decreased risk of long *** did not observe any credible subgroup effects for any risk *** The current body of literature presents several compelling risk factors for the development of long COVID in the pediatric *** research is necessary to elucidate the pathophysiology of long COVID.

关键词： COVID-19 Long COVID Post-acute COVID-19 syndrome Pediatrics Risk factors

Application of ultrasonography-elastography score to suspect porto-sinusoidal vascular disease in patients with portal vein thrombosis

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 20-24页

作者： Stefania Gioia Adriano De Santis Giulia d’Amati Silvia Nardelli alessandra Spagnoli Arianna Di Rocco Lorenzo Ridola Oliviero Riggio Department of Translational and Precision Medicine Sapienza University of RomeRomeItaly Department of Radiological Oncologicaland Pathological SciencesSapienza University of RomeRomeItaly Department of Public Health and Infectious Diseases Sapienza University of RomeRomeItaly

Background:Porto-sinusoidal vascular disease(PSVD)and portal vein thrombosis(PVT)are causes of portal hypertension characterized respectively by an intrahepatic and a pre-hepatic obstacle to the flow in the portal *** PVT may be a consequence of PSVD,in PVT patients at presentation,a pre-existing PSVD should be *** these patients the identification of an underlying PSVD would have relevant implication regarding follow-up and therapeutic management,but it could be *** this setting ultrasonography may be valuable in differential *** aim of the study was to use ultrasonography to identify parameters to discriminate between PSVD and“pure”PVT and then to suspect PVT secondary to a pre-existing ***:Fifty-three patients with histologically proven PSVD and forty-eight patients affected by chronic PVT were enrolled and submitted to abdominal ultrasonography with elastography by acoustic radiation force impulse(ARFI).Results:ARFI was higher and superior mesenteric vein(SMV)diameter was wider in PSVD patients than in PVT ***,a prognostic score was obtained as linear combinations of the two parameters with a good discrimination capacity between PSVD and PVT(the area under the curve=0.780;95%confidence interval:0.690-0.869).Conclusions:A score based on ARFI and SMV diameter may be useful to suspect an underlying PSVD in patients with PVT and to identify a subgroup of patients to be submitted to liver biopsy.

关键词： Non-cirrhotic portal hypertension Porto-sinusoidal vascular disease Chronic portal vein thrombosis Liver stiffness Portal hypertension Acoustic radiation force impulse