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Comparative study of microwave-assisted versus conventional heated reactions of biomass conversion into levulinic acid over hierarchical Mn_(3)O_(4)/ZSM-5 zeolite catalysts

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Carbon resources Conversion 2023年第3期6卷 245-252页

作者： Mazizah r.A.Helmi Dyah Utami C.rahayu Arnia P.Pratama irena Khatrin Anita N.ramadhani Yuni K.Krisnandi Department of Chemistry Faculty of Mathematics and Natural ScienceUniversitas IndonesiaDepok 16424Indonesia Solid Inorganic Framework Laboratory Department of ChemistryFaculty of Mathematics and Natural ScienceUniversitas IndonesiaDepok 16424Indonesia

Conversion of delignified cellulose from rice husk biomass,and model compounds of cellobiose and glucose to levulinic acid(LA)over hierarchical Mn_(3)O_(4)/ZSM-5 catalyst was carried out using a household microwave method,and then compared to the established conventional thermos-reaction *** hierarchical ZSM-5 was prepared using a double template method,aiming for micro and mesoporous systems developed in the *** as-prepared ZSM-5 were modified with Mn3O4 through incipient wetness impregnation with Mn2+solution followed by calcination at 550℃.The catalysts were characterized using various techniques such as powder XrD,SEM,BET,AAS,and FT-Ir which indicated the hierarchical structure of MFI zeolite(Si/Al of 30-34)with Mn loading of 2.14 wt%.The conversion products were analyzed using HPLC,1H NMr,and 13C NMr *** microwave-assisted reaction using 600 W for 180 s using delignified cellulose,cellobiose,and glucose gave conversion of 37.27%,46.35%,and 54.29%,respectively which is close to the conversion given by the conventional reaction carried out at 130◦C for 4 h(36.75%,55.62%,and 60.9%,respectively).Interestingly,the LA yield from the microwave-assisted reaction(4.33%,6.12%,and 9.57%)is higher than the yield from the conventional reaction,which only produced 5.2%,4.88%,and 6.93%*** microwaveassisted method is also shown to give less by-products compared to the thermochemical ***,it could be considered an alternative method for converting cellulose to LA.

关键词： Hierarchical ZSM-5 zeolite Levulinic acid Lignocellulose conversion Microwave-assisted synthesis Cellobiose Glucose

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Frequency-modulated second elements of two-element alarm calls do not enhance discrimination of callers in three Eura- sian ground squirrels

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Current Zoology 2012年第5期58卷 749-757页

作者： irena SCHNEIDErOVA Department of Zoology Faculty of Science Charles University in Prague Prague 128 44 Czech Republic

Alarm calls of the EuropeanSpermophilus citellus(EGS), TaurusS. taurensis(TGS) and AnatolianS. xanthoprymnus(AGS) ground squirrels share the same basic structure. They are tonal sounds consisting primarily of two different elements. The first element, often produced without the second element, has limited frequency modulation, while the second element is more frequency modulated. The present study examined whether this frequency-modulated element enhances the individual distinc-tiveness of calls, allowing calls to be ascribed with greater confidence to individual callers of the three species. Cross-validated discriminant function analysis (DFA) based on five acoustic parameters of the first element successfully classified calls to correct individuals (EGS: 90%, TGS: 98%, AGS: 96%). Cross-validated DFA based on five acoustic parameters of the second element was also successful in classifications (EGS: 88%, TGS: 86%, AGS: 96%), though discrimination of callers based on parameters of the second versus first element was the same for the AGS, lower for the EGS and significantly lower for the TGS. Cross-validated DFA based on five acoustic parameters of two-element calls also successfully classified calls to correct individuals (EGS: 93%, TGS: 98%, AGS: 97%), though did not improve the extent to which calls could be classified to individuals beyond that based on the first element alone. Thus, the second element does not enhance the individual distinctiveness of calls, but may convey other information such as the location of the caller.

关键词：频率调制报警电话元素松鼠声学参数交叉验证 EGS 达乌尔黄鼠

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risk of conduction disturbances following different transcatheter aortic valve prostheses:the role of aortic valve calcifications

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Journal of Geriatric Cardiology 2022年第3期19卷 167-176页

作者： Francesco Pollari Ferdinand Vogt irena Großmann Jill Marianowicz Marie Claes Steffen Pfeiffer Johannes Schwab Theodor Fischlein Cardiac Surgery Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Cardiology Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany radiology Klinikum NürnbergParacelsus Medical UniversityNurembergGermany

OBJECTIVES To assess the impact of prosthesis choice and aortic valve calcifications on the occurrence of conduction disturb-ances after transcatheter aortic valve implantation(TAVI).METHODS We retrospectively analyzed the preoperative clinical characteristics,electrocardiograms,contrast-enhanced mul-tidetector computed tomography scans and procedural strategies of patients who underwent TAVI in our center between January 2012 and June *** of calcium volume was performed for each aortic cusp above(aortic valve)and below(left ventricular outflow tract,LVOT)the basal *** analysis was performed to evaluate risk factors for the onset of new bundle branch block(BBB),transient and permanent atrioventricular block(tAVB,pAVB).rESULTS A total of 569 patients were included in the *** different prostheses were implanted(Edwards Sapien XT,n=162;Edwards Sapien 3,n=240;Medtronic CoreValve,n=27;Medtronic CoreValve Evolut r,n=21;Symetis Acurate,n=56;Sy-metis Acurate neo,n=63).The logistic regression analysis for BBB showed association with baseline left anterior *** logistic regression for tAVB,found the prior valvuloplasty and the balloon post-dilatation associated with the *** left and right BBB,degree of oversizing,and LVOT calcification beneath the non-coronary cusp were associated with *** the prosthesis model,nor the use of a self-expandable prosthesis showed statistical significance with the above-men-tioned outcomes on univariate *** LVOT calcification beneath the non-coronary cusp,baseline left anterior hemiblock,right BBB,balloon post-dilatation,prior valvuloplasty and oversizing are independently associated with postprocedural conduction disturbances after *** of a self-expandable prosthesis may show a lower incidence of AVB,if applied in lower calcified aortic valves.

关键词： aortic balloon conduction

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Cytotoxicity of new Ho(Ⅲ) and Pr(Ⅲ) complexes

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Journal of rare Earths 2010年第S1期28卷 40-46页

作者： irena Kostova Tsvetanka Stefanova Department of Chemistry Faculty of PharmacyMedical University2 Dunav St.Sofia 1000Bulgaria Department of Immunology Institute of MicrobiologyBulgarian Academy of Sciences26 Acad.G.Bonchev St.Sofia 1113Bulgaria

New complexes of coumarin-3-carboxylic acid(HCCA) with Ho(Ⅲ) and Pr(Ⅲ) were synthesized and their structures and spectral properties were investigated by elemental analysis,Ir,raman and NMr *** to the experimental data the complexes’ formula and geometries were *** frequencies,Ir intensities and raman activities as well as 1H NMr chemical shifts of HCCA and its Ho(Ⅲ) and Pr(Ⅲ) complexes were *** comparative experimental vibrational and NMr analyses of both the ligand and the Ln(Ⅲ) complexes predicted the bidentate binding to Ho(Ⅲ) and Pr(Ⅲ) through the deprotonated carboxylic oxygen and the carbonylic oxygen of the *** cytotoxic/cytostatic properties of the ligand and the newly synthesized complexes of coumarin-3-carboxylic acid with Ho(Ⅲ) and Pr(Ⅲ) were tested by MTT reduction assay against two mouse tumor cell lines:melanoma B16 and fibrosarcoma *** were also tested for cytotoxicity against normal mouse peritoneal *** proliferation inhibitory effect of the complexes compared to that of the ligand proved their cytotoxic/cytostatic properties against both the tumor cell *** addition,the complexes were less cytotoxic against normal mouse macrophages and were able to modulate NO release by activated *** obtained results were in accordance with our previously published data concerning the activity of lanthanide(Ⅲ) complexes with other coumarin derivatives.

关键词： coumarins Ho(Ⅲ),Pr(Ⅲ) FT-Ir,FT-raman NMr cytotoxic/cytostatic activity rare earths

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Liver transplantation for non-resectable colorectal liver metastases

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Hepatobiliary Surgery and Nutrition 2023年第4期12卷 595-597页

作者： Hassan Aziz Saima Sharif irena Gribovskaja-rupp Alan W.Hemming University of Iowa Hospitals and Clinics Iowa CityIAUSA

At present,there are no absolute practice guidelines for liver transplants in colorectal liver metastases(CrLM),and treatment protocols for unresectable CrLM are institution-specific(1).One of the first prospective studies evaluating the safety of liver transplants for CrLM was the SECA-I trial(1,2).A 5-year overall survival rate of 60% was observed in this trial,which far outperformed survival with chemotherapy alone(3).In the SECA-Ⅱ trial,enrollment was increased,and patients with better prognostic factors,including at least a 10% response to chemotherapy before the transplant,were selected.

关键词： Colorectal liver metastases(CrLM) liver transplant International Hepato-Pancreato-Biliary Association transplant oncology

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Transcript shortening via alternative polyadenylation promotes gene expression during fracture healing

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Bone research 2023年第1期11卷 163-177页

作者： Deepak Kumar Khajuria irena Nowak Ming Leung Vengadeshprabhu Karuppagounder Yuka Imamura Christopher C.Norbury Fadia Kamal reyad A.Elbarbary Department of Orthopaedics and rehabilitation The Pennsylvania State University College of MedicineHersheyPA17033USA Center for Orthopaedic research and Translational Science(COrTS) The Pennsylvania State University College of MedicineHersheyPA17033USA Institute for Personalized Medicine Penn State College of MedicineHersheyPA17033USA Department of Pharmacology The Pennsylvania State University College of MedicineHersheyPA17033USA Department of Microbiology and Immunology The Pennsylvania State University College of MedicineHersheyPA17033USA Department of Biochemistry and Molecular Biology The Pennsylvania State University College of MedicineHersheyPA17033USA Center for rNA Molecular Biology Pennsylvania State UniversityUniversity ParkPA16802USA

Maturation of the 3′end of almost all eukaryotic messenger rNAs(m rNAs)requires cleavage and *** mammalian m rNAs are polyadenylated at different sites within the last exon,generating alternative polyadenylation(APA)isoforms that have the same coding region but distinct 3′untranslated regions(UTrs).The 3′UTr contains motifs that regulate m rNA metabolism;thus,changing the 3′UTr length via APA can significantly affect gene *** ossification is a central process in bone healing,but the impact of APA on gene expression during this process is ***,we report the widespread occurrence of APA,which impacts multiple pathways that are known to participate in bone ***,the progression of endochondral ossification involves global 3′UTr shortening,which is coupled with an increased abundance of shortened transcripts relative to other transcripts;these results highlight the role of APA in promoting gene expression during endochondral bone *** mechanistic studies of transcripts that undergo APA in the fracture callus revealed an intricate regulatory network in which APA enhances the expression of the collagen,type I,alpha 1(Col1a1)and Col1a2 genes,which encode the 2 subunits of the abundantly expressed protein collagen *** exerts this effect by shortening the 3′UTrs of the Col1a1 and Col1a2 m rNAs,thus removing the binding sites of mi r-29a-3p,which would otherwise strongly promote the degradation of both *** together,our study is the first to characterize the crucial roles of APA in regulating the 3′UTr landscape and modulating gene expression during fracture healing.

关键词： healing metabolism shortening

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Colorectal cancer mortality trends in Serbia during 1991–2010:an age-period-cohort analysis and a joinpoint regression analysis

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Chinese Journal of Cancer 2016年第10期35卷 518-527页

作者： Milena Ilic irena Ilic Department of Epidemiology Faculty of Medical SciencesUniversity of Kragujevac Faculty of Medical Sciences University of Kragujevac

Background: For both men and women worldwide, colorectal cancer is among the leading causes of cancer-related death. This study aimed to assess the mortality trends of colorectal cancer in Serbia between 1991 and 2010, prior to the introduction of population-based ***: Joinpoint regression analysis was used to estimate average annual percent change(AAPC) with the corresponding 95% confidence interval(CI). Furthermore, age-period-cohort analysis was performed to examine the effects of birth cohort and calendar period on the observed temporal ***: We observed a significantly increased trend in colorectal cancer mortality in Serbia during the study period(AAPC = 1.6%, 95% CI 1.3%–1.8%). Colorectal cancer showed an increased mortality trend in both men(AAPC –2.2%) and women(AAPC rend of colorectal cancer mo= 2.0%, 95% CI 1.7%= 1.0%, 95% CI 0.6%–1.4%). The temporal trtality was significantly affected by birth cohort(P reas the study period did not significantly affect the trend(P = 0.072). Colorectal cancer mortality increased for the first several birth cohorts in Serbia(from 1916 to 1955), followed by downward flexion for people born after the 1960 s. According to comparability test, overall mortality trends for colon cancer and rectal and anal cancer were not parallel(the final selected model rejected parallelism, P rectal cancer mortality in Serbia increased considerably over the past two decades. Mortality increased particularly in men, but the trends were different according to age group and subsite. In Serbia, interventions to reduce colorectal cancer burden, especially the implementation of a national screening program, as well as treatment improvements and measures to encourage the adoption of a healthy lifestyle, are needed.

关键词：塞尔维亚队列分析结直肠癌回归分析死亡率连接点龄期大肠癌

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Improving Performance of Computer Algebra Systems

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Journal of Software Engineering and Applications 2023年第10期16卷 521-529页

作者： Kostas Zotos irena Atanassova Department of Informatics Faculty of Science and Mathematics South-West University “NeofitRilski” Blagoevgrad Bulgaria

Computer Algebra Systems have been extensively used in higher education. The reasons are many e.g., visualize mathematical problems, correlate real-world problems on a conceptual level, are flexible, simple to use, accessible from anywhere, etc. However, there is still room for improvement. Computer algebra system (CAS) optimization is the set of best practices and techniques to keep the CAS running optimally. Best practices are related to how to carry out a mathematical task or configure your system. In this paper, we are going to examine these techniques. The documentation sheets of CASs are the source of data that we used to compare them and examine their characteristics. The research results reveal that there are many tips that we can follow to accelerate performance.

关键词： Mathematical Software Computer Algebra Systems CAS Improving Performance CAS Performance CAS Optimization MATLAB Maple Mathematica

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Advantages & Disadvantages of Online CAS

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Journal of Software Engineering and Applications 2023年第9期16卷 496-504页

作者： Kostas Zotos irena Atanassova Department of Informatics Faculty of Science and Mathematics South-West University “Neofit Rilski” Blagoevgrad Bulgaria

Online Computer Algebra Systems (CAS) have become increasingly popular among students and teachers. The reasons are many such as being more flexible, simple to use, accessible from anywhere, etc. However, as with any educational tool, they also have some disadvantages that we should know. The purpose of this study is to analyze advantages and disadvantages of online CASs and propose some techniques to optimize CAS performance in order to reduce weaknesses. The research results reveal that online CAS versions are on the rise but lag in some capabilities in comparison with desktop versions.

关键词： Mathematical Software Online CAS Computer Algebra Systems Advantages of Online CAS CAS

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Standards of admission capillary blood glucose levels in cesarean born neonates

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World Journal of Pediatrics 2017年第5期13卷 433-438页

作者： Tatiana Smolkin irena Ulanovsky Pnina Carasso Imad r.Makhoul Department of Neonatology Ruth Rappaport Children’s HospitalHaifa IsraelRambam Health Care CampusHaifaIsrael The ruth&Bruce rappaport Faculty of Medicine.Technion—Israel Institute of Technology HaifaIsrael.

Background:Neonatal hypoglycemia (NH) and cutoffs remain *** center screens all cesareandelivered (CD) neonates for *** sought to define standards of admission capillary blood glucose levels (ACBGLs) in CD neonates who were at the lowest risk for ***:Of 4947 neonates,519 met all 14 inclusion *** highly-selected neonates were apparently the healthiest,least-stressed,earliest to be admitted to nursery and at lowest-risk for *** each CD,cord blood gases and glucose were determined and each infant was screened for blood glucose at nursery ***:Sampling age was 41.6±15.3 minutes,a mean ACBGL of 52.3±10.7 mg/dL,and percentiles as follows:1st percentile,29.2;3rd,33.6;5th,35.0;10th,39.0;25th,46.0;50th,51.0;75th,58.0;90th,67.0;95th,71.0;97th,73.0,and 99th,*** rose significantly with increasing gestational age (P=0.004),increasing cord blood glucose (Preasing cord blood pH (Preasing sampling age (P=4).027).Conclusions:Setting uniform ACBGL cutoffs for NH definition is unachievable due to the enormous heterogeneity among ***,we provide group-based ACBGL standards in CD *** propose setting ACBGL cutoffs for use in CD neonates:1) hypoglycemia:ACBGL rcentile (rventional hypoglycemia:ACBGL rcentile (<30 mg/dL).

关键词： capillary blood cesarean delivery glucose hypoglycemia newborn infant

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