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Electrically tunable generation of vectorial vortex beams with micro-patterned liquid crystal structures

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Chinese Optics Letters 2017年第7期15卷 4-8页

作者：冀志超张心正张玉娇王振华 irena drevensek-olenik Romano Rupp 李威吴强许京军The MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Institute of Applied Physics and School of Physics Nankai University The MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Institute of Applied Physics and School of PhysicsNankai University Synergetic Innovation Center of Chemical Science and Engineering Faculty of Mathematics and Physics University of Ljubljana and Department of Complex MatterJ. Stefan Institute Faculty of Physics Vienna University

We develop a new method for smooth and continuous space-variant alignment of the liquid crystal medium in micro-patterned structures, which is based on a radial micro-structured pattern of polymeric ribbons exhibiting out-of-plane orientation with respect to the ITO-coated glass plates. Thanks to the broad range of electrical tunability of the optical retardation for the micro-patterned liquid crystal structures, transformation of the fundamental Gaussian beam into different types of specific beams, including generalized cylindrical vector beams, vortex beams, and vectorial vortex beams, is efficiently demonstrated.

关键词： vortex tunable retardation alignment polymeric coated structured ribbon segmented superposition

Influence of symmetric and asymmetric rolling on texture evolution of work-hardened AA 5xxx aluminium alloy

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Transactions of Nonferrous Metals Society of China 2024年

作者： Matja? Godec Stefan Zaefferer Jakob Kraner ?rtomir Donik irena Paulin Institute of Metals and Technology Max-Planck-Institut für Eisenforschung， Max-Planck-Strasse 1 Impol 2000 d.d.， Partizanska cesta 38

The textures and microstructures of hot- and cold-rolled sheets of an AA 5454 aluminium alloy were studied， with special attention paid to comparing the texture development for the symmetric and asymmetric cold rolling. Scanning electron microscopy with electron-backscatter diffraction was used to monitor the development of the microstructure in the differently deformed and additionally annealed samples. Details of the formations and transformations of individual texture components occurring during the rolling processes were observed and discussed. The average grain sizes， textures and mechanical properties were correlated and explained for the symmetric and asymmetric cold-rolled samples. The asymmetric rolling is beneficial in terms of deep drawability because it reduces the planar anisotropy of the annealed material due to the decrease of the Cube， Goss， Rotated Cube and η- fibre texture components and the same time strengthens X1- and X2-fibre texture components which are shear texture components and improve deep drawability. During the asymmetric cold rolling， the temperature increases due to friction， triggering recrystallisation processes and leading to larger grains. It was also confirmed that asymmetric cold rolling uses less rolling force and consequently less energy to produce a final material with better formability， particularly earing.

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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 European Spermophilus citellus （EGS）, Taurus S. taurensis （TGS） and Anatolian S. 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 individu- als （EGS： 93%, TGS： 98%, AGS： 97%）, though did not improve the extent to which calls could be classified to individuals be- yond that based on the ftrst 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 [Current Zoology 58 （5）： 749-757, 2012].

关键词： Alarm call Ground squirrel Individual recognition Spermophilus citeUus Spermophilus taurensis Spermophilusxanthoprymnus

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

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 < 0.05), whereas 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 < 0.05).Conclusions: We found that colorectal 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

Cadmium regulation by Lasius niger A contribution to understanding high metal levels in ants

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Insect Science 2009年第1期16卷 89-92页

作者： irena M. Grzes Institute of Environmental Sciences Jagiellonian University Gronostajowa 7 30-387 Krakow Poland

Ants （Formicinae, Hymenoptera） are considered efficient accumulators of Zn and Cd. In this study the relationship between Cd concentrations in soil and in Lasius niger workers was assessed for 20 colonies located along a gradient of Cd pollution. As soil Cd concentration increased from 1 to 8 mg/kg, ant body Cd concentration increased rapidly to about 40 mg/kg, and remained stable at this level, through a progressive increase of soil Cd concentration from 8 to 21 mg/kg. The phase of rapid increase confirms the high ability of L. niger for Cd accumulation, while the stabilization of Cd body concentration indicates either increasing elimination rate or decreasing rate of uptake. Therefore it can be concluded that Lasius niger has a high ability to accumulate Cd, but simultaneously an ability for Cd regulation was detected.

关键词： accumulation ants elimination heavy metals pollution gradient regulation

International patterns in incidence and mortality trends of pancreatic cancer in the last three decades: A joinpoint regression analysis

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World Journal of Gastroenterology 2022年第32期28卷 4697-4714页

作者： irena Ilic Milena Ilic Faculty of Medicine University of BelgradeBelgrade 11000Serbia Department of Epidemiology Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia

BACKGROUND Pancreatic cancer,as the one of most fatal malignancies,remains a critical issue in the global burden of *** To estimate trends in pancreatic cancer incidence and mortality worldwide in the last three *** A descriptive epidemiological study was *** cancer incidence and mortality data were obtained from the database of the World Health *** of pancreatic cancer incidence and mortality during 2020 was *** age-standardized rates(ASRs,expressed per 100000)were *** estimate trends of incidence and mortality of pancreatic cancer,joinpoint regression analysis was used:the average annual percent change(AAPC)with the corresponding 95%confidence interval(95%CI)was ***,analysis was performed by sex and *** this paper,the trend analysis included only countries with high and medium data *** A total of 495773(262865 male and 232908 female)new cases and 466003(246840 male and 219163 female)deaths from pancreatic cancer were reported worldwide in *** both sexes,most of the new cases(191348;38.6%of the total)and deaths(182074;39.1%of the total)occurred in the Western Pacific *** both sexes,the highest ASRs were found in the European Region,while the lowest rates were reported in the South-East Asia *** general pattern of rising pancreatic cancer incidence and mortality was seen across countries worldwide in observed *** of all countries with an increase in pancreatic cancer incidence,females in France and India showed the most marked rise in incidence rates(AAPC=+3.9%and AAPC=+3.7%,respectively).Decreasing incidence trends for pancreatic cancer were observed in some countries,but without *** of all countries with an increase in pancreatic cancer mortality rates,Turkmenistan showed the most marked rise both in males(AAPC=+10.0%,95%CI:7.4–12.5)and females(AAPC=+6.4%,95%CI:3.5–9.5).The mortality trends of pancreatic cancer were decreasin

关键词： Pancreatic cancer Incidence Mortality Joinpoint analysis International pattern

Epidemiology of stomach cancer

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World Journal of Gastroenterology 2022年第12期28卷 1187-1203页

作者： Milena Ilic irena Ilic Department of Epidemiology Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia Faculty of Medicine University of BelgradeBelgrade 11000Serbia

Despite a decline in incidence and mortality during the last decades,stomach cancer is one of the main health challenges *** to the GLOBOCAN 2020 estimates,stomach cancer caused approximately 800000 deaths(accounting for 7.7%of all cancer deaths),and ranks as the fourth leading cause of cancer deaths in both genders *** 1.1 million new cases of stomach cancer were diagnosed in 2020(accounting for 5.6%of all cancer cases).About 75%of all new cases and all deaths from stomach cancer are reported in *** cancer is one of the most lethal malignant tumors,with a five-year survival rate of around 20%.There are some well-established risk factors for stomach cancer:Helicobacter pylori infection,dietary factors,tobacco,obesity,and *** date,the most important way of preventing stomach cancer is reduced exposure to risk factors,as well as screening and early *** research on risk factors can help identify various opportunities for more effective *** programs for stomach cancer have been implemented in a few countries,either as a national or opportunistic screening of high-risk individuals ***,due to its high aggressiveness and heterogeneity,stomach cancer still remains a severe global health problem.

关键词： Stomach cancer Epidemiology Incidence Mortality Survival Predictive factors Prevention

Epidemiology of pancreatic cancer

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World Journal of Gastroenterology 2016年第44期22卷 9694-9705页

作者： Milena Ilic irena Ilic Faculty of Medical Sciences University of Kragujevac

Cancer of the pancreas remains one of the deadliest cancer types. Based on the GLOBOCAN 2012 estimates, pancreatic cancer causes more than 331000 deaths per year, ranking as the seventh leading cause of cancer death in both sexes together. Globally, about 338000 people had pancreatic cancer in 2012, making it the 11^(th) most common cancer. The highest incidence and mortality rates of pancreatic cancer are found in developed countries. Trends for pancreatic cancer incidence and mortality varied considerably in the world. A known cause of pancreatic cancer is tobacco smoking. This risk factor is likely to explain some of the international variations and gender differences. The overall five-year survival rate is about 6%(ranges from 2% to 9%), but this vary very small between developed and developing countries. To date, the causes of pancreatic cancer are still insufficiently known, although certain risk factors have been identified, such as smoking, obesity, genetics, diabetes, diet, inactivity. There are no current screening recommendations for pancreatic cancer, so primary prevention is of utmost importance. A better understanding of the etiology and identifying the risk factors is essential for the primary prevention of this disease.

关键词： Pancreatic cancer Epidemiology Incidence Mortality Trend Risk factors