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Quantifying the refractive index dispersion of a pigmented biological tissue using Jamin–Lebedeff interference microscopy

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Light(Science & Applications) 2013年第1期2卷 58-63页

作者： doekele G Stavenga Hein L Leertouwer bodo d wilts Computational Physics Zernike Institute for Advanced MaterialsUniversity of GroningenNL-9747 AG GroningenThe Netherlands

Jamin–Lebedeff polarizing interference microscopy is a classical method for determining the refractive index and thickness of transparent ***,we extend the application of this method to pigmented,absorbing biological tissues,based on a theoretical derivation using Jones *** novel method is applied to the wings of the American Rubyspot damselfly,Hetaerina *** membranes in the red-colored parts of the damselfly’s wings,with a thickness of 2.5 μm,contain a pigment with maximal absorption at 490 nm and a peak absorbance coefficient of 0.7 μm^(-1).The high pigment density causes a considerable and anomalous dispersion of the refractive *** result can be quantitatively understood from the pigment absorbance spectrum by applying the Kramers–Kronig dispersion *** of the spectral dependence of the refractive index and the absorption are valuable for gaining quantitative insight into how the material properties of animal tissues influence coloration.

关键词： absorption chitin insect wings Jones calculus Kramers–Kronig relations

High refractive index of melanin in shiny occipital feathers of a bird of paradise

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Light(Science & Applications) 2015年第1期4卷 518-523页

作者： doekele G Stavenga Hein L Leertouwer daniel C Osorio bodo d wilts Computational Physics University of Groningen9747 AGThe Netherlands School of Life Sciences University of SussexBrightonBN19QGUK Adolphe Merkle Institute University of FribourgCH-1700 FribourgSwitzerland

Male Lawes’s Parotia,a bird of paradise,use the highly directional reflection of the structurally colored,brilliant-silvery occipital feathers in their courtship *** in other birds,the structural coloration is produced by ordered melanin *** barbules of the Parotia’s occipital feathers,with thickness,3 μm,contain 6–7 layers of densely packed melanin rodlets(diameter,0.25 μm,length,2 μm).The effectively,0.2 μm thick melanin layers separated by,0.2 μm thick keratin layers create a multilayer interference *** measurements yielded peak wavelengths in the near-infrared at,1.3 μm,i.e.,far outside the visible wavelength *** the Jamin-Lebedeff interference microscopy method recently developed for pigmented media,we here determined the refractive index of the intact *** thus derived the wavelength dependence of the refractive index of the barbules’melanin to be 1.7–1.8 in the visible wavelength *** the anatomical and refractive index data in an optical multilayer model,we calculated the barbules’reflectance,transmittance and absorptance spectra,thereby confirming measured spectra.

关键词： bird of paradise interference reflector iridescence Jamin-Lebedeff microscopy multilayer

Association between Placental Malaria and Severe Pre-Eclampsia in Two University Hospitals of Yaounde City

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Open Journal of Obstetrics and Gynecology 2024年第9期14卷 1488-1511页

作者： Ayissi Gregory Astrid Ruth Ndolo Kondo Ndoumba Afouba Alice Noa Ndoua Claude Cyrille Essiben Félix Meka Esther Belinga Etienne Metogo Junie Engo Engo Samuel désiré bodo Edmond Lemaire Tchente Nguefack Charlotte Foumane Pascal Mboudou Emile Télésphore department of Obstetrics and Gynecology Faculty of Medicine and Biomedicals Sciences University of Yaound I Yaounde Cameroon department of Obstetrics and Gynecology Faculty of Medicine and Pharmaceuticals Sciences University of Douala Douala Cameroon department of Morphological and Anatomo-Pathological Sciences Faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon. department of Morphological and Anatomo-Pathological Sciences Faculty of Medicine and Biomedicals Sciences University of Yaound I Yaounde Cameroon

Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: The objective of our study was to investigate the association between placental malaria lesions and severe pre-eclampsia. Methodology: We conducted a prospective analytical cross-sectional study in two University Hospitals in the city of Yaounde (Yaounde Central Hospital and the Gynaecological Obstetrics and Paediatrics Hospital), and in the laboratory of the Centre Pasteur in Yaounde over an eight-month period (1st January 2021 – 1st September 2021). All patients with pre-eclampsia diagnosed according to the criteria of the International Society for the Study of Hypertension (ISSHP) and free of chronic metabolic or infectious pathology were included in this study. The patients were divided into two groups: group 1 (mild pre-eclampsia) and group 2: severe pre-eclampsia. Socio-demographic, clinical and histopathological characteristics specific to pre-eclampsia and placental malaria were investigated. Statistical analysis was performed with SPSS 23.0 software, Chi 2 was used to compare categorical variables, Student t-test was used to compare means, and logistic regression was used to assess the association between placental malaria lesions and PES. Results: The mean age of our study population was 29.93 ± 7.36 years versus 28.28 ± 7.18 years in patients with mild and severe pre-eclampsia respectively. Pre-eclampsia placental lesions (accelerated villous maturation, infarction) were significantly greater in patients with severe pre-eclampsia (p Conclusion: Placental malaria lesions were significantly associated with severe pre-eclampsia and increased the risk of developing severe pre-eclampsia placental lesions by a factor of 10.

关键词： Mild Pre-Eclampsia Severe Pre-Eclampsia Malaria Placental Lesions Association

Reactive pathways toward parasitic release of singlet oxygen in metal-air batteries

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npj Computational Materials 2021年第1期7卷 1135-1142页

作者： Adriano Pierini Sergio Brutti Enrico bodo department of Chemistry University of Rome“La Sapienza”RomeItaly GISEL—Centro di Riferimento Nazionale per i Sistemi di Accumulo Elettrochimico di Energia FirenzeItaly

The superoxide disproportionation reaction is a key step in the chemistry of aprotic metal oxygen batteries that controls the peroxide formation upon discharge and opens the way for singlet oxygen *** we clarify the energy landscape of the disproportionation of superoxide in aprotic media catalyzed by group 1A *** analysis is based on ab initio multireference computational methods and unveils the competition between the expected reactive path leading to peroxide and an unexpected reaction channel that involves the reduction of the alkaline *** channels lead to the release of triplet and singlet O_(2).The existence of this reduction channel not only facilitates singlet oxygen release but leads to a reactive neutral solvated species that can onset parasitic chemistries due to their well-known reducing ***,we show that the application of moderate overpotentials makes both these channels accessible in aprotic batteries.

关键词： properties release singlet

Effects of variable retention harvesting on canopy transpiration in a red pine plantation forest

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Ecological Processes 2022年第1期11卷 374-385页

作者： Alanna V.bodo M.Altaf Arain School of Earth Environment and SocietyMcMaster University1280 Main Street WestHamiltonON L8S 4K1Canada McMaster Centre for Climate Change McMaster University1280 Main Street WestHamiltonON L8S 4K1Canada

Background:Variable Retention Harvesting(VRH)is a forest management practice applied to enhance forest growth,improve biodiversity,preserve ecosystem function and provide economic revenue from harvested *** are many different forms and compositions in which VRH is applied in forest *** this study,the impacts of four different VRH treatments on transpiration were evaluated in an 83-year-old red pine(Pinus Pinus resinosa)plantation forest in the Great Lakes region in *** VRH treatments included 55%aggregated crown retention(55A),55%dispersed crown retention(55d),33%aggregated crown retention(33A),33%dispersed crown retention(33d)and unharvested control(CN)*** VRH treatments were implemented in 1-ha plots in the winter of 2014,while sap flow measurements were conducted from 2018 to ***:Study results showed that tree-level transpiration was highest among trees in the 55d treatment,followed by 33d,55A,33A and CN *** found that photosynthetically active radiation(PAR)and vapor pressure deficit(VPd)were major controls or drivers of transpiration in all VRH *** study suggests that dispersed or distributed retention of 55%basal area(55d)is the ideal forest management technique to enhance transpiration and forest ***:This study will help researchers,forest managers and decision-makers to improve their understanding of water cycling in forest ecosystem and adopt the best forest management regimes to enhance forest growth,health and resiliency to climate change.

关键词： Variable Retention Harvesting Forest management Transpiration Sap flow Red pine Great Lakes region

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Symmetry Adapted Block diagonalisation in Equivariant Steady State Bifurcation Problems and its Numerical Application

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数学进展 1991年第4期 455-487页

作者： Peter Stork,bodo Werner Institut fur Angewandte Mathematik der Universitat Hamburg Bundesstr.55 d-2000 Hamburg 13 Federal Republic of Germany Institut fur Angewandte Mathematik der Universitat Hamburg Bundesstr.55 d-2000 Hamburg 13 Federal Republic of Germany

Considering steady state bifurcation of single parameter r-equivariant systemswhere Γ is a compact Lie group acting on X via a faithful orthogonal representation, we simultaneously block-diagonalise all jacobians of g along a solution path with respect to symmetry adapted subspaces and apply bifurcation groups to reduce symmetry breaking bifurcation points to simple bifurcation points. In generical situations this algorithm allows for numerically stable use of continuation methods and steady state bifurcation point detection and computation. The large scale decrease of computing efforts is demonstrated at computing the equilibria of a hexagonal lattice dome with 21 degrees of freedom, we present a great variety of solution arcs with symmetry from full d6 down to Z2 symmetry.

关键词： Symmetry Adapted Block diagonalisation in Equivariant Steady State Bifurcation Problems and its Numerical Application

Anxiety and depression in adult patients with celiac disease on a gluten-free diet

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World Journal of Gastroenterology 2010年第22期16卷 2780-2787页

作者： Winfried Huser Karl-Heinz Janke bodo Klump Michael Gregor Andreas Hinz department of Internal Medicine I Klinikum Saarbrücken Winterberg 1 D-66119 Saarbrücken and Department of Psychosomatic Medicine and Psychotherapie Technische Universitt München Baden-Württemberg State Health Office District Government Stuttgart Gastroenterology and Gastrointestinal Cancer St. Anna Hospital Obere Waiblinger Starβe 101 D-70374 Stuttgart Germany and Department of Internal Medicine 1 Universittskliniken Tübingen department of Internal Medicine 1 Universittskliniken Tübingen department of Medical Psychology and Medical Sociology Universitt Leipzig

AIM: To compare anxiety and depression levels in adult patients with celiac disease (Cd) on a gluten-free diet (GFd) with ***: The levels of anxiety, depression and of a probable anxiety or depressive disorder were assessed by the Hospital Anxiety and depression Scale in 441 adult patients with Cd recruited by the German Celiac Society, in 235 age-and sex-matched patients with inflammatory bowel disease (IBd) in remission or with slight disease activity, and in 441 adult persons of a representative German general population sample (GP). Potential demographic (age, sex, social class, family status) and disease-related (latency to diagnosis, duration of GFd, compliance with GFd, thyroid disease) predictors of anxiety and depression in Cd were tested for by regression analyses. RESULTS: The level of anxiety in Cd patients was predicted (R 2 = 0.07) by female gender (P = 0.01). Female sex (OR = 3.6, 95% CI: 1.3-9.4, P = 0.01) was associated with a probable anxiety disorder. Living alone (OR = 0.5, 95% CI: 0.2-0.9, P = 0.05) was associated with a reduced risk of an anxiety disorder. The level of depression and a probable depressive disorder were not predicted by any of the demographic and medical variables tested for. The levels of anxiety in patients with Cd (6.6 ± 3.4) and with IBd (6.9 ± 3.7) were higher than those of persons in the GP (4.6 ± 3.3) (both P depression in persons with Cd (4.2 ± 3.4), IBd (4.6 ± 3.4) and of the GP (4.2 ± 3.8) did not differ (P = 0.3). The prevalence of a probable anxiety disorder in persons with Cd (16.8%) and IBd (14.0%) was higher than that of the GP (5.7%) (P depressive disorder did not differ significantly between the three groups (P = 0.1). CONCLUSION: Anxiety in adult German female celiacs on a GFd is higher than in persons of the GP. Female celiacs on a GFd should be screened for anxiety.

关键词： Celiac disease Anxiety depression Gender

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吸湿对单向亚麻纤维复合材料力学性能的影响

复合材料学报 2022年第2期39卷 608-616页

作者：贾云龙 FIEdLER bodo 常州工学院航空与机械工程学院/飞行学院常州213032 汉堡工业大学聚合物与复合材料研究所汉堡D21073

为探明亚麻纤维增强树脂复合材料(FFRPs)在长期潮湿环境中的力学性能变化规律,基于真空辅助树脂模塑传递成型(VARTM)手段制备了的干燥状态的单向FFRPs(纤维体积分数为40vol%)。试验研究了FFRPs在30°C、80%相对湿度(RH)环境中放置5天、3... 详细信息

为探明亚麻纤维增强树脂复合材料(FFRPs)在长期潮湿环境中的力学性能变化规律,基于真空辅助树脂模塑传递成型(VARTM)手段制备了的干燥状态的单向FFRPs(纤维体积分数为40vol%)。试验研究了FFRPs在30°C、80%相对湿度(RH)环境中放置5天、35天、86天后拉伸力学性能变化。结果表明,FFRPs在湿热环境中吸水量近似符合一维情况下的Fickian第二定律,饱和吸水量为5.3%左右。FFRPs在垂直于纤维方向上的拉伸强度和模量随吸湿度增加递减,断口微观分析表明吸湿降低了纤维基体界面结合性能。然而,FFRPs在纤维方向上的拉伸强度并未因吸湿降低,反而在吸湿过程呈现出先减小后增加的趋势,此变化规律文献中尚未报道:相比干燥状态,放置5天后拉伸强度下降5.7%;放置35天后拉伸强度增加18.7%;放置86天时样品已处在饱和吸湿状态,拉伸强度略微减小,但仍比干燥状态增加13.7%。FFRPs在纤维取向上拉伸强度变化可解释为多因素共同作用的结果。

关键词：植物纤维复合材料亚麻纤维吸湿拉伸力学性能耐久性

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Brevipedicelones d and E,Two C-O-C Flavonoid dimmers from the Leaves of Garcinia brevipedicellata and Anti-onchocercal Activity

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Natural Products and Bioprospecting 2019年第1期9卷 61-68页

作者： Mirabel Akongwi Anastasie ETih Kennedy d.Nyongbela Moses Samje Raphael T.Ghogomu Bernard bodo department of Organic Chemistry Faculty of ScienceUniversity of Yaounde 1P.O.Box 812YaoundeCameroon Pharmacochemistry Research Laboratory Department of ChemistryFaculty of ScienceUniversity of BueaP.O.Box 63BueaSouth West RegionCameroon Faculty of Science ANDI Centre of Excellence on Onchocerciasis ResearchUniversity of BueaP.O.Box 63BueaSouth West RegionCameroon Laboratoire de Chimie des Substances Naturelles Muse´um National d’Histoire Naturelle63 Rue Buffon75005 ParisFrance

A novel isoflavone–chromone flavonoid C–O–C dimmer,brevipedicelone d(1),along with one new C–O–C biflavonoid derivative,brevipedicelone E(2),were isolated from the ethyl acetate extract of the leaves of Garcinia brevipedicellata,a medicinal plant used in folk medicine in parts of *** structures were elucidated by extensive spectroscopic techniques,including 1d-and 2d-NMR,MS experiments,as well as comparing their spectral data with those of known ***-onchocercal screening of 1 showed moderate inhibition of adult worm motility of Onchocerca ochengi by 60%at the highest concentration(20 μg/mL)and inhibited motility of both the juvenile worms of *** and Loa loa by 90%at this same concentration.

关键词： Garcinia brevipedicellata Brevipedicelone Anti-onchocercal activity