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Bracken-induced increase in soil P availability, along with its high P acquisition efficiency, enables it to invade P-deficient meadows

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Journal of Plant Ecology 2022年第4期15卷 783-794页

作者： Antun Jelinčić nina Šajna Željka Zgorelec aleksandra Perčin Ćire Truhelke 1510000 ZagrebCroatia University of Maribor Faculty of Natural Sciences and MathematicsDepartment of BiologyMariborSlovenia University of Zagreb Faculty of AgricultureDepartment of General AgronomyZagrebCroatia

Changes in soil chemistry after invasion by bracken(Pteridium aquilinum)have been studied in heathlands,but comparable studies in meadows are *** investigated if bracken invasion into P-deficient meadows alters the soil nutrient-resource pool,as well as the mechanisms behind it linked to soil processes and bracken ***,we investigated how community composition responds to differences in soil chemistry before and after the *** and plant material sampling,along with vegetation survey,were performed during bracken peak *** analyses included analysis of variance and canonical correspondence analysis(CCA).Bracken invasion increased soil P availability,soil organic C concentration,as well as C:n,C:S and n:S ratios,while decreasing Fe and Co *** pinnae were rich in P,and its rhizomes were rich in K,whereas n:P of pinnae and rhizomes was *** showed contrasting abundance patterns of frequent meadow species related to P and K *** lanatus exhibited competitive advantage under extremely low P *** in P availability under bracken may have occurred through promoting the leaching of Fe and *** increasing P availability for its growth and increasing n limitation for other species,bracken can gain a competitive advantage from the soil resource-niche *** ability to increase soil P availability,along with the physiological mechanisms behind its high P acquisition efficiency,seem to differentiate bracken from other species of competitive ecological strategy,which are mainly confined to nutrient-rich *** enabled bracken to invade P-deficient meadows.

关键词： Pteridium aquilinum vegetation succession biogeochemical processes plant–soil feedbacks Holcus lanatus phosphorus limitation plant invasion

Upconversion FRET quantitation:the role of donor photoexcitation mode and compositional architecture on the decay and intensity based responses

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Light(Science & Applications) 2022年第10期11卷 2321-2334页

作者： Agata Mkotulska aleksandra Pilch-WrÓbel Satu Lahtinen Tero Soukka Artur Bednarkiewicz Division of Biomedical Physicochemistry Institute of Low Temperature and Structure ResearchPANul.Okolna 2Wroclaw 50-422Poland Department of Life Technologies/Biotechnology University of TurkuKiinamyllynkatu 1020520 TurkuFinland

Lanthanide-doped colloidal nanoparticles capable of photon upconversion(UC)offer long luminescence lifetimes,narrowband absorption and emission spectra,and efficient anti-Stokes *** features are highly advantageous for F?rster Resonance Energy Transfer(FRET)based *** nanoparticles(UCnPs)as donors may solve the existing problems of molecular FRET systems,such as photobleaching and limitations in quantitative analysis,but these new labels also bring new *** we have studied the impact of the core-shell compositional architecture of upconverting nanoparticle donors and the mode of photoexcitation on the performance of UC-FRET from UCnPs to Rose Bengal(RB)molecular *** have quantitatively compared luminescence rise and decay kinetics of Er3+emission using core-only naYF4:20%Yb,2%Er and core-shell naYF4:20%Yb@naYF4:20%Yb,5%Er donor UCnPs under three photoexcitation schemes:(1)direct short-pulse photoexcitation of Er3+at 520 nm;indirect photoexcitation of Er3+through Yb3+sensitizer with(2)980 nm short(5-7 ns)or(3)980 nm long(4 ms)laser *** donor luminescence kinetics and steady-state emission spectra differed between the UCnP architectures and excitation *** for highly sensitive kinetic upconversion FRET-based biomolecular assays,the experimental results underline the complexity of the excitation and energy-migration mechanisms affecting the Er3+donor responses and suggest ways to optimize the photoexcitation scheme and the architecture of the UCnPs used as luminescent donors.

关键词： excitation donor decay

On the Generalized Strongly nil-Clean Property of Matrix Rings

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Algebra Colloquium 2021年第4期28卷 625-634页

作者： aleksandra S.Kostic Zoran Z.Petrovic Zoran S.Pucanovic Maja Roslavcev Faculty of Mathematics University of Belgrade Studentski trg 1611000 BelgradeSerbia Faculty of Civil Engineering University of Belgrade Bulevar kralja Aleksandra 7311000 BelgradeSerbia

Let R be an associative unital ring and not necessarily *** analyze conditions under which every n×n matrix A over R is expressible as a sum A=E1+…+Es+n of(commuting)idempotent matrices Ei and a nilpotent matrix n.

关键词： idempotent matrix nilpotent matrix nil-clean ring matrix ring

Drain amylase value as an early predictor of pancreatic fistula after cephalic duodenopancreatectomy

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World Journal of Gastroenterology 2014年第26期20卷 8691-8699页

作者： Vladimir D Dugalic Djordje M Knezevic Vladan n Obradovic Miroslava G Gojnic-Dugalic Slavko V Matic aleksandra R Pavlovic-Markovic Predrag D Dugalic Srbislav M Knezevic Department of Hepatobiliary and Pancreatic Surgery First Surgical University HospitalClinical Center of SerbiaSchool of MedicineUniversity of Belgrade St. Joseph’s Hospital Health Center Clinic for Gynecology and Obstetrics Clinical Center of SerbiaSchool of MedicineUniversity of Belgrade Clinic for Gastroenterology and Hepatology Clinical Center of SerbiaSchool of MedicineUniversity of Belgrade Clinic for Gastroenterology and Hepatology University Hospital Zemun

AIM: To determine predictors of clinically relevant pancreatic fistulas (CRPF) by measuring drain fluid amylase (DFA) in the early postoperative period.

关键词： Cephalic duodenopancreatectomy Periampullary tumors Pancreatic fistula Drain fluid amylase level Prediction

Predictors of heart rhythm disturbances in hypertensive obese patients with obstructive sleep apnea

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Journal of Geriatric Cardiology 2017年第9期14卷 553-562页

作者： Lyudmila Sergeevna Korostovtseva nadezhda Edvinovna Zvartau Oxana Petrovna Rotar Yurii Vladimirovich Sviryaev aleksandra Olegovna Konradi Research Department for Hypertension Almazov National Medical Research Centre St Petersburg Russia Institute of TranslationalMedicine ITMO University St Petersburg Russia

Objective To assess the incidence and predictors of heart rhythm and conduction disturbances in hypertensive obese patients with andwithout obstructive sleep apnea （OSA）. Methods This is an open, cohort, prospective study. Out of 493 screened patients, we selected 279hypertensive, obese individuals without severe concomitant diseases： 75 patients without sleep-disordered breathing （non-SDB group）, and204 patients with OSA （OSA group）. At baseline, all patients underwent examination, including ECG, Holter ECG monitoring, and sleepstudy. During follow-up （on 3, 5, 7 and 10th years; phone calls once per 6 months）, information about new events, changes in therapy and lifestyle was collected, diagnostic procedures were performed. As the endpoints, we registered significant heart rhythm and conduction disordersas following： atrial fibrillation （AF）, ventricular tachycardia, atrioventricular block （AV） 2-3 degree, sinoatrial block, significant sinus pauses（〉 2000 ms）, and the required pacemaker implantation. Results The median follow-up was 108 （67.5-120） months. The frequency of heartrhythm disorders was higher in OSA patients （29 cases, X^2= 5.5; P = 0.019） compared to the non-SDB patients （three cases; OR： 3.92, 95%CI： 1.16-13.29）. AF was registered in 15 patients （n = 12 in OSA group; P = 0.77）. Heart conduction disturbance developed in 16 patients,without an association with the rate of coronary artery disease onset. Regression analysis showed that only hypertension duration was anindependent predictor olAF （OR： 1.10, 95% CI： 1.04-1.16; P = 0.001）. In case of heart conduction disturbances, apnea duration was thestrongest predictor （P = 0.002）. Conclusions Hypertensive obese patients with OSA demonstrate 4-fold higher incidence of heart rhythmand conduction disturbances than subjects without SDB. Hypertension duration is an independent predictor for AF development, while sleepapneaJhypopnea duration is the main factor for heart conduction disorders onset in hypertensiv

关键词： Atrial fibrillation Cardiovascular morbidity Cardiovascular prognosis Heart conduction disorder Obstructive sleep apnea

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World Journal of Stem Cells 2019年第6期11卷 347-374页

作者： Urszula Kozlowska Agnieszka Krawczenko Katarzyna Futoma Tomasz Jurek Marta Rorat Dariusz Patrzalek aleksandra Klimczak Hirszfeld Institute of Immunology and Experimental Therapy Polish Academy of SciencesWroclaw 53-114Poland Department of Forensic Medicine Wroclaw Medical UniversityWroclaw 50-345Poland Faculty of Health Science Department of PhysiotherapyWroclaw Medical UniversityWroclaw 50-367Poland

BACKGROUnD Mesenchymal stromal/stem cells (MSCs) constitute a promising tool in regenerative medicine and can be isolated from different human tissues. However, their biological properties are still not fully characterized. Whereas MSCs from different tissue exhibit many common characteristics, their biological activity and some markers are different and depend on their tissue of origin. Understanding the factors that underlie MSC biology should constitute important points for consideration for researchers interested in clinical MSC application. AIM To characterize the biological activity of MSCs during longterm culture isolated from: bone marrow (BM-MSCs), adipose tissue (AT-MSCs), skeletal muscles (SMMSCs), and skin (SK-MSCs). METHODS MSCs were isolated from the tissues, cultured for 10 passages, and assessed for: phenotype with immunofluorescence and flow cytometry, multipotency with differentiation capacity for osteo-, chondro-, and adipogenesis, stemness markers with qPCR for mRnA for Sox2 and Oct4, and genetic stability for p53 and c-Myc;27 bioactive factors were screened using the multiplex ELISA array, and spontaneous fusion involving a co-culture of SM-MSCs with BM-MSCs or AT-MSCs stained with PKH26 (red) or PKH67 (green) was performed. RESULTS All MSCs showed the basic MSC phenotype;however, their expression decreased during the follow-up period, as confirmed by fluorescence intensity. The examined MSCs express CD146 marker associated with proangiogenic properties;however their expression decreased in AT-MSCs and SM-MSCs, but was maintained in BM-MSCs. In contrast, in SK-MSCs CD146 expression increased in late passages. All MSCs, except BM-MSCs, expressed PW1, a marker associated with differentiation capacity and apoptosis. BM-MSCs and AT-MSCs expressed stemness markers Sox2 and Oct4 in long-term culture. All MSCs showed a stable p53 and c-Myc expression. BM-MSCs and AT-MSCs maintained their differentiation capacity during the follow-up period. In contrast

关键词： Mesenchymal stem/progenitor cells Bone marrow MSCs Adipose tissue MSCs Muscle-derived MSCs Skin-derived MSCs Cytokines and trophic factors of MSCs Spontaneous fusion of MSCs

Anisotropic iron-doping patterns in two-dimensional cobalt oxide nanoislands on Au(111)

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nano Research 2019年第9期12卷 2364-2372页

作者： Anthony Curto Zhaozong Sun Jonathan Rodriguez-Fernandez Liang Zhang Ayush Parikh Ting Tan Jeppe V. Lauritsen aleksandra Vojvodic Department of Chemical and Biomolecular Engineering University of PennsylvaniaPhiladelphiaPA 19104USA Interdisciplinary nanoscience Center (inAnO) Aarhus University8000 Aarhus CDenmark

An in teg rated approach combi ning den sity functional theory(DFT)calculati ons and atomic resol utio n sea nning tun neling microscopy(STM)is used to study well-defined iron-doped cobalt oxide nanoislands supported on Au(111).The focus is on the structure and distribution of Fe dopants within these nanoislands of CoO as a function of Fe to Co *** DFT and STM results agree strongly and complement each other to allow for a more complete un dersta nding of the dopa nt structure trends on the nano *** Fe as a marker,we first find that the stacki ng seque nee of the moire structure of the host cobalt oxide nano islands can be ide ntified un ambiguously through a combinati on of DFT and *** the distinct con trast of the embedded Fe dopa nt atoms as observed with atom-resolved STM,we find correlatio ns betwee n Fe dopa nt positi on and the CoO/Au(111)moire patter n at varyi ng Fe dopa nt den *** n of Fe-dopa nt clusters within the nano islands is investigated in detail through DFT and found to agree with the dopant patter ns observed in *** find that the structural effects of Fe dopants throughout the nanoislands with the basal planes and the two types of edges—the oxygen and metal edges—have different *** DFT calculations and STM images show a strong preferenee for Fe dopants to be located directly on or near the oxygen edge of the nanoislands as opposed to being directly on or n ear the metal *** n together,our results illustrate that Fe dopa nt incorporati on and distributi on within CoO nanoislands are highly an isotropic and gover ned by both the moire structure of the basal planes as well as nano-size effects present at the under-coordinated edges of different local geometry and chemistries.

关键词： seanning tunneling microscopy(STM) density functional theory(DFT) cobalt oxide transition metal oxides mixed transition metal oxides

From trees to fleas: masting indirectly affects flea abundance on a rodent host

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Integrative Zoology 2023年第3期18卷 440-452页

作者： Ivan BALÁŽ MichałBOGDZIEWICZ Sylwia DZIEMIAn-ZWOLAK Carlotta LO PRESTI aleksandra WRÓBEL Milena ZDUnIAK RafałZWOLAK Faculty of natural Sciences and Informatics Constantine the Philosopher University in NitraNitraSlovakia Department of Systematic Zoology Adam Mickiewicz University in Pozna´nPozna´nPoland InRAE LESSEMUniversity Grenoble AlpesSaint-Martind’HèresFrance University of Catania CataniaItaly Department of Zoology Pozna´n University of Life SciencesPozna´nPoland

Mast seeding causes strongﬂuctuations in populations of forest ***,this phenomenon can be used as a natural experiment to examine how variation in host abundance affects parasite *** investigatedﬂeas infesting yellow-necked mice in beech forest after 2 mast and 2 non-mast *** tested 2 mutually exclusive scenarios:(1)as predicted by classical models of density-dependent transmission,an increase in host density will cause an increase in ectoparasite abundance(deﬁned as the number of parasites per host),versus(2)an increase in host density will cause a decline inﬂea abundance(“dilution,”which is thought to occur when parasite population growth is slower than that of the host).In addition,we assessed whether masting alters the relationship between host traits(sex and body mass)andﬂea *** found a hump-shaped relationship between host andﬂea ***,the most basic predictions are too simple to describe ectoparasite dynamics in this *** addition,masting modiﬁed seasonal dynamics ofﬂea abundance,but did not affect the relationship between host traits andﬂea abundance(individuals with the highest body mass hosted the mostﬂeas;after controlling for body mass,parasite abundance did not vary between sexes).Our results demonstrate that pulses of tree reproduction can indirectly,through changes in host densities,drive patterns of ectoparasite infestation.

关键词： Apodemusﬂavicollis Fagus sylvatica indirect effects pulsed resources Siphonaptera

Utility of different serum fibrosis markers in diagnosing patients with chronic pancreatitis and pancreatic adenocarcinoma

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World Journal of Gastrointestinal Oncology 2016年第8期8卷 635-641页

作者： Anna Kozak Renata Talar-Wojnarowska aleksandra Kaczka Anna Borkowska Leszek Czupryniak Ewa Malecka-Panas Anita Gasiorowska Department of Digestive Tract Diseases Medical University of Lodz Department of Diabetology and Metabolic Diseases Medical University of Lodz

AIM: To estimate the levels of serum cytokines in chronic pancreatitis(CP) and pancreatic ductal adenocarcinoma(PDAC) patients in order to evaluate their usefulness as possible ***: The study included 167 Caucasian patients: 74 with PDAC(28 men and 42 women, aged 30-88 years), 78 with CP(50 men and 21 women, aged 20-79 years) and 15 age-matched healthy controls hospitalized in the Department of Digestive Tract Diseases, Medical University of Lodz, Poland between 2006 and 2013. Serum MCP-1, transforming growth factor(TGF)-β1, HA and s-Fr were measured in patients with CP(n = 78), PDAC(n = 74) and healthy controls(n = 15) using ELISA(Corgenix United Kingdom Ltd R and D Systems). The severity of CP was assessed according to the Cambridge ***: Both patients with CP and PDAC had a significantly higher mean TGF-β1 serum level(1066 ± 582and 888 ± 356 vs 264 ± 93, P n s-Fr(2.42 ± 1.385 and 2.41 ± 1.275 vs 0.6 ± 0.370, P nd mean HA(199 ± 254 and 270 ± 358 vs 40 ± 26, P ntrols. There was no difference in mean MCP-1 between all the groups. There were no significant differences in any cytokine levels between the PC and PDAC groups. no significant differences between serum cytokines depending on age, gender or smoking status were found in CP patients. Mean s-Fr concentration was significantly higher in CP, lasting longer than 5 years compared to those with a shorter disease clinical course(2.639 ± 1.125 vs 1.870 ± 0.970, P no correlation between tumor size, localization or TnM classification and serum TGF-β1, MCP-1, s-Fr and HA levels in patients with PDAC. no significant differences between cytokines depending on diabetes presence in CP were found. nevertheless, mean serum TGF-β1 concentration in PDAC patients was higher in those with diabetes compared to the remaining group(986 vs 839, P = 0.043). COnCLUSIOn: Serum TGF-β1, s-Fr and HA may be considered additional diagnostic ma

关键词： Fibrosis Chronic pancreatitis Soluble type fractalkine Pancreatic adenocarcinoma Transforming growth factor beta-1 Hyaluronic acid Monocyte chemoattractant protein-1