Сезонная динамика зараженности Harpalus rufipes (Coleoptera, Carabidae) грегаринами в агроэкосистеме

Relationships in the “parasite-host” system are closely interrelated and occur at all levels from the molecular to behavioral and population ones. There are two models of realization of these relations. The first case is when the parasites are uniformly distributed in the host population. High extensiveness of invasion is accompanied by its low intensity. The second case is when a part of host population is infected with parasites, but the negative impact is manifested to the maximum extent. Invasion of the ground beetle Harpalus rufipes (De Geer, 1774), dwelling in sweet corn agroecosystems located in the vicinity of Dnipropetrovsk near Doslidnoe village, by several gregarines species is investigated in this study. H. rufipes is an abundant, ubiquitous species, living in extremely wide range of terrestrial ecosystems, with especially high populations inhabiting anthropogenically transformed environments. H. rufipes has a wide range of feeding. This species is distributed in the Central and Eastern Europe, and introduced to North America. Gregarines were found in the intestines of 20 individuals of H. rufipes from 190 (10.5%): Gregarina ovata Dufour, 1828, G. steini Berndt, 1902, G. amarae (Hammerschmidt, 1839) Frantzius, 1848, Clitellocephalus ophoni (Tuzet and Ormieres, 1956) Clopton, 2002, Torogregarina sphinx Clopton, 1998, Gigaductus macrospora Filipponi, 1948 and G. elongatus (Moriggi, 1943) Filipponi, 1948. There is high level of infestation of C. ophoni and G. steini. At the same time, not more than three species of the gregarines were localized in the beetle body. Seasonal dynamic of occurrence of the gregarines is as follows. Maximal indices of occurrence are found at the end of August (22.2%) and minimal ones at the end of June (4.8%). The highest total number of gregarines (383 ind.) is recorded at the end of August, the lowest one is fixed at the beginning of September (33 ind.). Indices of gregarine species dominance are as follows: C. ophoni – 34.0%, G. macrospora – 28.9%, G. steini – 20.6%, T. sphinx – 9.3%, G. amarae – 5.5%, G. ovata – 0.9% and G. elongatus – 0.4%. High temperatures in July and August helped to increase infection of H. rufipes by almost all gregarines compared to cool and wet conditions in June. The highest value of the index of abundance corresponds to the time of high average intensity of infestation by three common species of gregarines. Decline in abundance index by the end of summer and early fall may be due to the death of heavily infected individuals. High level of infection does not cause the pathogenic effect on the host organism.Исследована зараженность грегаринами Harpalus rufipes (De Geer, 1774) – одного из важнейших вредителей зерновых культур, обитающих в агроэкосистеме кукурузы сахарной, расположенной в окрестностях г. Днепропетровск возле пос. Дослидное. Кишеч­ник имаго данного вида жужелиц исследовали компрессорным методом. H. rufipes заражен семью видами грегарин: Gregarina ovata Dufour, 1828, G. steini Berndt, 1902, G. amarae (Hammerschmidt, 1839) Frantzius, 1848, Clitellocephalus ophoni (Tuzet and Ormieres, 1956) Clopton, 2002, Torogregarina sphinx Clopton, 1998, Gigaductus macrospora Filipponi, 1948 и G. elongatus (Moriggi, 1943) Filipponi, 1948. Одновременно в организме одного жука локализовались не более трех видов грегарин. В летние месяцы показатель экстенсивности инвазии минимален в июне (4,8%) и достигает максимального значения в конце августа (22,2%). Наибольшая суммарная численность грегарин (383 экз.) всех обнаруженных видов зафиксирована в конце августа, наименьшая – в начале сентября (33 экз.). В кишечнике одновременно находятся гамонты и сизигии всех обнаруженных видов грегарин. Наивысшая средняя интенсивность инвазии двумя массовыми видами грегарин для C. ophoni установлена в конце июля (146 экз.), наименьшая – в конце августа (2), для G. macrospora – в конце августа (70) и в начале сентября (4 экз.) соответственно. Большая средняя интенсивность инвазии в конце июля приводит к увеличению числа сизигиев C. ophoni с преобладанием их в 7 раз по сравнению с данными июня. Нахождение в кишечнике H. rufipes грегарин свидетельствует о способности жука быть дефинитивным хозяином данных видов споровиков.Исследована зараженность грегаринами Harpalus rufipes (De Geer, 1774) – одного из важнейших вредителей зерновых культур, обитающих в агроэкосистеме кукурузы сахарной, расположенной в окрестностях г. Днепропетровск возле пос. Дослидное. Кишеч­ник имаго данного вида жужелиц исследовали компрессорным методом. H. rufipes заражен семью видами грегарин: Gregarina ovata Dufour, 1828, G. steini Berndt, 1902, G. amarae (Hammerschmidt, 1839) Frantzius, 1848, Clitellocephalus ophoni (Tuzet and Ormieres, 1956) Clopton, 2002, Torogregarina sphinx Clopton, 1998, Gigaductus macrospora Filipponi, 1948 и G. elongatus (Moriggi, 1943) Filipponi, 1948. Одновременно в организме одного жука локализовались не более трех видов грегарин. В летние месяцы показатель экстенсивности инвазии минимален в июне (4,8%) и достигает максимального значения в конце августа (22,2%). Наибольшая суммарная численность грегарин (383 экз.) всех обнаруженных видов зафиксирована в конце августа, наименьшая – в начале сентября (33 экз.). В кишечнике одновременно находятся гамонты и сизигии всех обнаруженных видов грегарин. Наивысшая средняя интенсивность инвазии двумя массовыми видами грегарин для C. ophoni установлена в конце июля (146 экз.), наименьшая – в конце августа (2), для G. macrospora – в конце августа (70) и в начале сентября (4 экз.) соответственно. Большая средняя интенсивность инвазии в конце июля приводит к увеличению числа сизигиев C. ophoni с преобладанием их в 7 раз по сравнению с данными июня. Нахождение в кишечнике H. rufipes грегарин свидетельствует о способности жука быть дефинитивным хозяином данных видов споровиков

Some extensions of the class of convex bodies

We introduce and study a new class of \eps-convex bodies (extending the class of convex bodies) in metric and normed linear spaces. We analyze relations between characteristic properties of convex bodies, demonstrate how \eps-convex bodies connect with some classical results of Convex Geometry, as Helly theorem, and find applications to geometric tomography. We introduce the notion of a circular projection and investigate the problem of determination of \eps-convex bodies by their projection-type images. The results generalize corresponding stability theorems by H. Groemer

Decoration of nanovesicles with pH (low) insertion peptide (pHLIP) for targeted delivery

Acidity at surface of cancer cells is a hallmark of tumor microenvironments, which does not depend on tumor perfusion, thus it may serve as a general biomarker for targeting tumor cells. We used the pH (low) insertion peptide (pHLIP) for decoration of liposomes and niosomes. pHLIP senses pH at the surface of cancer cells and inserts into the membrane of targeted cells, and brings nanomaterial to close proximity of cellular membrane. DMPC liposomes and Tween 20 or Span 20 niosomes with and without pHLIP in their coating were fully characterized in order to obtain fundamental understanding on nanocarrier features and facilitate the rational design of acidity sensitive nanovectors. The samples stability over time and in presence of serum was demonstrated. The size, ζ-potential, and morphology of nanovectors, as well as their ability to entrap a hydrophilic probe and modulate its release were investigated. pHLIP decorated vesicles could be useful to obtain a prolonged (modified) release of biological active substances for targeting tumors and other acidic diseased tissues

Tuning a Polar Molecule for Selective Cytoplasmic Delivery by a pH (Low) Insertion Peptide

Drug molecules are typically hydrophobic and small in order to traverse membranes to reach cytoplasmic targets, but we have discovered that more polar molecules can be delivered across membranes using water-soluble, moderately hydrophobic membrane peptides of the pHLIP (pH low insertion peptide) family. Delivery of polar cargo molecules could expand the chemical landscape for pharmacological agents that have useful activity but are too polar by normal drug criteria. The spontaneous insertion and folding of the pHLIP peptide across a lipid bilayer seeks a free energy minimum, and insertion is accompanied by a release of energy that can be used to translocate cell-impermeable cargo molecules. In this study, we report our first attempt to tune the hydrophobicity of a polar cargo, phallacidin, in a systematic manner. We present the design, synthesis, and characterization of three phallacidin cargoes, where the hydrophobicity of the cargo was tuned by the attachment of diamines of various lengths of hydrophobic chains. The phallacidin cargoes were conjugated to pHLIP and shown to selectively inhibit the proliferation of cancer cells in a concentration-dependent manner at low pH

Light-induced surface sliding of the nematic director in liquid crystals

We report the effect of light-induced sliding of the nematic director over an isotropic boundary surface in an azo-dye doped liquid-crystal cell. We show that illumination of the cell with polarized laser light induces transient dynamic sliding followed by permanent reorientation of the director. The two effects are in competition and tend to orient the director along mutually orthogonal directions. The sliding can be controlled and even completely quenched by the amount of induced anchoring energy. A physical model is proposed which accounts for the experimental results. [S0031-9007(99) PACS numbers: 42.70. Df, 61.30.Cz Light-induced anchoring and reorientation effects in liquid crystals (LC) have been the subject of intense research interests in recent years Optical reorientation was originally concerned with light fields acting on the bulk of a liquid crystal cell, the aligning surface determining only the boundary conditions in the reorientation process. Gibbons et al. These results stimulated an interest to investigate the possibility of getting free surface sliding of the nematic director under the control of the incident light. In the paper of Marusii et al. [8], the authors interpreted the observed molecular reorientation close to the isotropic control surface as an effect of director sliding. However, the impossibility of changing the anchoring energy in their experiment did not allow one to establish definitively the actual nature of the phenomenon. In this paper we report the first clear demonstration of the effect of molecular director sliding over an isotropic surface endowed with very weak anchoring energy. We show that illumination with polarized laser light of an azo-dye doped LC cell induces both a transient dynamic sliding and a permanent reorientation of the molecular director. These two effects are regulated by different physical mechanisms and occur on different time scales. The key points of our experimental observations are (i) on a macroscopic scale, i.e., in the frame of the continuum theory, free director sliding over an isotropic boundary surface is possible, and (ii) this effect can be controlled and even completely quenched by the amount of anchoring energy induced on the surface. The scheme of the experimental setup is shown in The exciting polarized beam from He-Cd laser ͑l 0.442 mm; P 1 mW͒ was focused on the cell from the size of the control surface by the lens L 1 . The director reorientation over this surface was detected by checking the polarization state of a He-Ne laser probe beam ͑l 0.638 mm; P 0.1 mW͒ crossing the cell from the side of the reference surface. The electric field E p of the probe beam was set parallel to the initial director orientation n 0 , and the signal transmitted through an analyzer crossed to it was detected. In this geometry, any rotation of the molecular director (up to 90 ± ) over the control surface led to an increase of the transmitted signal. In fact, in our experimental conditions the Mauguin regime was 0031-9007͞99͞82(9)͞1855(4)$15.0

Targeted Imaging of Urothelium Carcinoma in Human Bladders by an ICG pHLIP Peptide Ex vivo

Bladder cancer is the fifth most common in incidence and one of the most expensive cancers to treat. Early detection greatly improves the chances of survival and bladder preservation. The pH Low Insertion Peptide (pHLIP® peptide) conjugated with a near infrared fluorescent dye (ICG) targets low extracellular pH allowing visualization of malignant lesions in human bladder carcinoma ex vivo. Cystectomy specimens obtained after radical surgery were immediately irrigated with non-buffered saline and instilled with a solution of the ICG pHLIP® construct, incubated, and rinsed. Bladders were subsequently opened and imaged, the fluorescent spots were marked, and a standard pathological analysis was carried out to establish the correlation between ICG pHLIP® imaging and white light pathological assessment. Accurate targeting of bladder lesions was achieved with a sensitivity of 97%. Specificity is 100%, but reduced to 80%, if targeting of necrotic tissue from previous transurethral resections or chemotherapy are considered as false positives. ICG pHLIP® imaging agent marked high grade urothelial carcinomas, both muscle invasive and non-muscle invasive. Carcinoma in situ (CIS) was accurately diagnosed in 11 cases, whereas only 4 cases were seen using white light, so imaging with the ICG pHLIP® peptide offers improved early diagnosis of bladder cancers, and may also enable new treatment alternatives

Ordering of droplets and light scattering in polymer dispersed liquid crystal films

We study the effects of droplet ordering in initial optical transmittance through polymer dispersed liquid crystal (PDLC) films prepared in the presence of an electrical field. The experimental data are interpreted by using a theoretical approach to light scattering in PDLC films that explicitly relates optical transmittance and the order parameters characterizing both the orientational structures inside bipolar droplets and orientational distribution of the droplets. The theory relies on the Rayleigh-Gans approximation and uses the Percus-Yevick approximation to take into account the effects due to droplet positional correlations.Comment: revtex4, 18 pages, 8 figure

Nonsmooth analysis of doubly nonlinear evolution equations

In this paper we analyze a broad class of abstract doubly nonlinear evolution equations in Banach spaces, driven by nonsmooth and nonconvex energies. We provide some general sufficient conditions, on the dissipation potential and the energy functional,for existence of solutions to the related Cauchy problem. We prove our main existence result by passing to the limit in a time-discretization scheme with variational techniques. Finally, we discuss an application to a material model in finite-strain elasticity.Comment: 45 page