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We measure the entropy of formation of the interface upon anion adsorption (Cl-, Br- I- and SO42-) on Au(111) as an important indicator for the structure, order and composition of the interface. The entropy of formation of the interface exhibits a rather universal behaviour for all anions with a steep decrease upon initial adsorption followed by a shallow minimum at intermediate anion coverages and a strong increase close to the completion of the adsorbate adlayer. The strong variation of the entropy signals significant entropic contributions to the free enthalpy of the adsorption process and thus the stability of the adsorbed phase. At low anion coverages, close to the potential of zero charge, we attribute the entropy variations to the rearrangement of the interfacial water structure. At intermediate and high anion coverages, a comparison with the results of a lattice-gas model, considering pairwise repulsive interactions within the quasi-chemical approximation, shows that the entropy changes upon anion adsorption can be explained by the configurational entropy of the adsorbed phase. Thus, entropic contributions from both the solvent and the adsorbate are important for the stability of surface phases, particularly for disordered systems.
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The lifecycle of Brachymeria podagrica, a parasitic wasp with a worldwide distribution, was studied under laboratory conditions using the flesh fly, Sarcophaga dux, as a host. Two hundred parasite-free 3rd instars of S. dux were exposed for 24 h to 20 female B. podagrica. In daily intervals, maggots and later pupae were examined for developmental stages of the parasitoid. The whole pre-imaginal development at a temperature of 26 °C lasted 21 to 26 days. Three morphologically different instars, followed by a prepupal and a pupal stage, were described using light and scanning electron microscopy. In a second experiment with 100 3rd stage Sarcophaga larvae and 10 parasitoids, a total of 70 wasps emerged 20 to 25 days after exposure. Two fly larvae did not pupate and dried out, while 28 pupae contained a dry or caseous content, dead wasp imagos, or their larval stages. No fly imagines emerged from exposed groups, while all 100 unexposed larvae pupated and adults eclosed between day 12 and day 14 after the start of the experiment, while the imagoes of the parasitoids appeared 8 to 12 days later.
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Dípteros , Sarcofagídeos , Vespas , Animais , Feminino , Dípteros/parasitologia , Larva , Pupa/parasitologiaRESUMO
Opisthorchis felineus is a food-borne trematode which causes opisthorchiosis and affects mainly the liver and bile ducts of the liver with a possible risk of bile duct carcinogenesis resulting in cholangiocarcinoma. In Russia, O. felineus is mainly endemic in Western Siberia (Ob and Irtysh river basins) and occurs throughout the Volga, Kama, Don, and Dnepr river basins. The prevalence, intensity, and clinical significance of human infections and the incidence of cholangiocarcinoma vary geographically in endemic regions. Currently, there is substantial evidence on genetic variation of O. felineus, but information on the population genetic structure is so far very scarce. Because microsatellite DNA of this parasite is not available, we for the first time isolated sufficient microsatellite loci to examine the genetic diversity and population structure of O. felineus, using multiple nuclear loci approach. A total of ten highly polymorphic microsatellite loci from a constructed enriched genomic DNA library were characterized, using 29 samples representing huge O. felineus metapopulation extended in latitude over 5000 km from Middle Europe to Western Siberia. At least three populations can be discerned as result of analysis of the microsatellite loci genetic diversity. Based on the results for the first time, a hypothesis was put forward about the formation of a modern habitat of O. felineus.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Opistorquíase , Opisthorchis , Animais , Humanos , Opisthorchis/genética , Opistorquíase/epidemiologia , Opistorquíase/veterinária , Colangiocarcinoma/patologia , Repetições de Microssatélites , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/patologia , Variação GenéticaRESUMO
The formation of an appropriate solid electrolyte interphase (SEI) at the anode of a sodium battery is crucially dependent on the electrochemical stability of solvent and electrolyte at the redox potential of Na/Na+ in the respective system. In order to determine entropic contributions to the relative stability of the electrolyte solution, we measure the reaction entropy of Na metal deposition for diglyme (DG) and propylene carbonate (PC) based electrolyte solutions by electrochemical microcalorimetry at single electrodes. We found a large positive reaction entropy for Na+ deposition in DG of ΔR S DG ≈ ${S\left({\rm { DG}}\right)\approx \ }$ 234â J mol-1 K-1 (c.f.: ΔR S PC ≈ ${S\left({\rm { PC}}\right)\approx \ }$ 83â J mol-1 K-1 ), which signals substantial entropic destabilization of Na+ in DG by about 0.73â eV, thus increasing the stability of solvent and electrolyte relative to Na+ reduction. We attribute this strong entropic destabilization to a highly negative solvation entropy of Na+ , due to the low dielectric constant and high freezing entropy of DG.
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The front cover artwork is provided by Dr. Marco Schönig from Prof. Rolf Schuster's group at the Karlsruhe Institute of Technology. The image shows a gold surface under electrochemical control covered by two different, unspecified adsorbed species. In the inset, we present the result of our heat of reaction measurements, which showed that for Au(111) in sulfuric acid solutions the adsorbing anionic species is sulfate. Read the full text of the Research Article at 10.1002/cphc.202200227.
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Ouro , Sulfatos , Adsorção , CalorimetriaRESUMO
We investigate compositional changes of an electrochemical interface upon polarization with electrochemical microcalorimetry. From the heat exchanged at a Au(111) electrode upon sulfate adsorption, we determine the reaction entropy of the adsorption process for both neutral and acidic solutions, where the dominant species in solution changes from SO4 2- to HSO4 - . In neutral solution, the reaction entropy is about 40â J mol-1 K-1 more positive than that in acidic solution over the complete sulfate adsorption region. This entropy offset is explicable by a deprotonation step of HSO4 - preceding sulfate adsorption in acidic solution, which shows that the adsorbing species is SO4 * in both solutions. The observed overall variation of the reaction entropy in the sulfate adsorption region of ca. 80â J mol-1 K-1 indicates significant sulfate-coverage dependent entropic contributions to the Free Enthalpy of the surface system.
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Sulfatos , Adsorção , Calorimetria , Eletrodos , TermodinâmicaRESUMO
Cat domestication likely initiated as a symbiotic relationship between wildcats (Felis silvestris subspecies) and the peoples of developing agrarian societies in the Fertile Crescent. As humans transitioned from hunter-gatherers to farmers ~12,000 years ago, bold wildcats likely capitalized on increased prey density (i.e., rodents). Humans benefited from the cats' predation on these vermin. To refine the site(s) of cat domestication, over 1000 random-bred cats of primarily Eurasian descent were genotyped for single-nucleotide variants and short tandem repeats. The overall cat population structure suggested a single worldwide population with significant isolation by the distance of peripheral subpopulations. The cat population heterozygosity decreased as genetic distance from the proposed cat progenitor's (F.s. lybica) natural habitat increased. Domestic cat origins are focused in the eastern Mediterranean Basin, spreading to nearby islands, and southernly via the Levantine coast into the Nile Valley. Cat population diversity supports the migration patterns of humans and other symbiotic species.
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Domesticação , Repetições de Microssatélites , Animais , Gatos/genética , Genótipo , Oriente MédioRESUMO
Although Joyeuxiella pasqualei is frequently detected in cats from Mediterranean Europe, information on its biology is still scarce. This cestode is relatively less frequently reported in dogs, possibly because it is often misdiagnosed with the better-known Dipylidium caninum. The occurrence of J. pasqualei proglottids in a dog living in a closed environment triggered us to delve into the biology of this cestode by collecting biological samples from lizards and a road-killed cat. Two reptile species, Podarcis siculus (Lacertidae), and Tarentola mauritanica (Geckonidae) were also collected in the garden and its surroundings. In addition, experimental infections with eggs obtained from gravid proglottids were performed in laboratory mice, and Tenebrio molitor (Coleoptera: Tenebrionidae) beetles. Proglottids from the dog's feces and adult cestodes detected at necroscopy of a cat were morphologically identified as J. pasqualei. Two out of 13 T. mauritanica collected in the garden had natural infections of J. pasqualei cysts in the liver and attached to the intestine. All P. siculus lizards and experimentally infected rodents and beetles were negative. DNA sequences obtained from J. pasqualei showed the highest nucleotide similarities with Versteria sp., Echinococcus sp., Raillietina sonini, Taenia polyacantha and D. caninum. Data herein provided show the inability of rodents to become infected by direct ingestion of gravid proglottids, suggesting a need for an invertebrate first intermediate host in the life cycle. Thus, more research study is advocated to better understand the biology of J. pasqualei such as its first intermediate host and its mechanism of transmission in reptiles and rodents.
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Doenças do Gato , Cestoides , Infecções por Cestoides , Camundongos , Cães , Gatos , Animais , Infecções por Cestoides/veterinária , Infecções por Cestoides/epidemiologia , Doenças do Gato/epidemiologia , Cestoides/genética , Fezes , Europa (Continente)/epidemiologiaRESUMO
Air sac nematodes from birds are known for more than 200 years now and Filaria attenuata was the first described species from falcons, owl and corvid birds. The superficial description and the loss of the original material made F. attenuata a species inquirenda. Seurat (1915) redescribed the species with material from lanner falcon and pallid harrier from Algeria and based on this description Bain and Mawson, Rec S Aust Mus 18:265-28, (1981) created a new species, Serratospiculum seurati, by adding some, slightly divergent, measurements. The current paper is based on light and scanning electron microscopy of five male and 10 female S. seurati specimens from a Peregrine falcon that acquired the infection in Pakistan. The length of the slender male and female nematodes varied between 42-70 and 165-221 mm, respectively, spicules of unequal shape and length measured 292-325 and 638-785 µm. S. seurati was also found in Saker, Barbary and crossbreed falcons.
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Doenças das Aves/parasitologia , Falconiformes/parasitologia , Spirurina/classificação , Animais , Feminino , Masculino , Camundongos , Microscopia , Paquistão , Spirurina/citologia , Spirurina/isolamento & purificaçãoRESUMO
Five bacterial strains, UAE-HKU57T, UAE-HKU58, UAE-HKU59, UAE-HKU60 and UAE-HKU61, were isolated in Dubai, UAE, from necrotic foot tissue samples of four dromedaries (Camelus dromedarius) and associated maggots (Wohrlfartia species). They were non-sporulating, Gram-negative, non-motile bacilli. They grew well under aerobic conditions at 37 °C, but not anaerobically. The pH range for growth was pH 7.0-9.0 (optimum, pH 7.5-8.0) and the strains could tolerate NaCl concentrations (w/v) up to 2â% (optimum, 0.5â%). They were catalase- and cytochrome oxidase-positive, but caseinase-, gelatinase- and urease-negative. Their phenotypic characters were distinguishable from other closely related species. Phylogenetic analyses of the almost-complete 16S rRNA gene and partial 23S rRNA gene, gyrB, groEL and recA sequences revealed that the five isolates were most closely related to undescribed Ignatzschineria strain F8392 and Ignatzschineria indica, but in most phylogenies clustered separately from these close relatives. Average nucleotide identity analysis showed that genomes of the five isolates (2.47-2.52 Mb, G+C content 41.71-41.86 mol%) were 98.00-99.97% similar to each other, but ≤87.18â% similar to other Ignatzschineriaspecies/strains. Low DNA relatedness between the five isolates to other Ignatzschineriaspecies/strains was also supported by Genome-to-Genome Distance Calculator analysis. The chemotaxonomic traits of the five strains were highly similar. They were non-susceptible (intermediate or resistant) to tetracycline and resistant to trimethoprim/sulphamethoxazole. The name Ignatzschineria cameli sp. nov. is proposed to accommodate these five strains, with strain UAE-HKU57T (=CCOS1165T=NBRC 113042T) as the type strain.
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Camelus/microbiologia , Gammaproteobacteria/classificação , Larva/microbiologia , Necrose/microbiologia , Filogenia , Sarcofagídeos/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Pé/microbiologia , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Genes Bacterianos , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química , Emirados Árabes UnidosRESUMO
Domesticated Old World camels (Camelus dromedarius and Camelus bactrianus) are important for the economy of several countries in Asia, Africa, and the Arabian Peninsula, and coccidiosis is an important disease in camels. There is confusion concerning the species of coccidian parasites in camels and their life cycles. Although five species of Eimeria (E. cameli, E. rajasthani, E. dromedarii, E. bactriani, and E. pellerdyi) were named from camels, E. cameli is considered the most pathogenic. Here, development of gametogonic stages and oocysts of E. cameli are described in the lamina propria of the small intestines of naturally infected camels. Only sexual stages have been confirmed.
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Camelus/parasitologia , Coccidiose/veterinária , Eimeria/crescimento & desenvolvimento , Intestino Delgado/parasitologia , Mucosa/parasitologia , África , Animais , Ásia , Coccidiose/diagnóstico , Coccidiose/parasitologia , Feminino , Oocistos/classificaçãoRESUMO
Although the life cycle of the equid stomach parasite Habronema muscae was disclosed more than 100 years ago, little is known about the effect of the developing nematode larvae in its intermediate host, Musca domestica. In a series of experiments, freshly hatched M. domestica larvae were exposed to H. muscae eggs contained in a faecal sample of a naturally infected horse. In daily intervals, 50 fly larvae were removed and transferred on a parasite-free larval rearing medium where they completed their development. Hatched flies were examined for the presence of Habronema third-stage larvae. In two subsequent control groups, flies spend their entire larval life in contaminated horse faeces and in a parasite-free larval rearing medium, respectively. Out of the 700 fly larvae used in the infection experiments, 304 developed into adult flies of which 281 were infected. The average nematode larval burden rose from 3.6 in the group with the shortest exposure to more than 25 in the groups with the longest exposure. The proportion of larvae that developed into the adult insect fell from 82 % in the uninfected control group to 27 % in the positive control group. The pupae of the positive control group were smaller and lighter than those of the uninfected control group. Lower pupal size and weight in the positive control group as well as a lower insect developing rate might be attributed to the destruction of adipose cells in the maggots by Habronema larvae.
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Doenças dos Cavalos/parasitologia , Doenças dos Cavalos/transmissão , Muscidae/parasitologia , Infecções por Spirurida/veterinária , Spiruroidea/crescimento & desenvolvimento , Animais , Cavalos , Larva/crescimento & desenvolvimento , Larva/parasitologia , Muscidae/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Pupa/parasitologia , Infecções por Spirurida/parasitologia , Infecções por Spirurida/transmissão , Spiruroidea/fisiologiaRESUMO
In UAE, camel Physocephalus dromedarii was diagnosed for the first time in 2011 in dromedaries from a farm that previously had imported animals from foreign countries. The large scarab beetle, Scarabaeus cristatus, was found to be the major intermediate host for this parasite in Dubai. A total of 638 specimens of S. cristatus were collected and examined for the presence of third-stage larvae of nematode larvae at two sites in the Dubai Emirate (Emirates Industry for Camel Milk and Products and horse endurance training track) within a distance of 15 km. Third-stage larvae of P. dromedarii were detected in 94 and 97 % of beetles collected from the territory of the camel milk farm and the endurance training track, respectively. In addition to third-stage larvae, 264 beetles contained second-stage larvae. Only four beetles were infected with other than P. dromedarii larvae. The average larval burden in beetles from camel milk farm was significantly higher compared to those in beetles collected from the other site (1538 vs. 697). Comparison of larval burdens in juvenile and adult beetles collected at the camel milk farm showed a significantly higher intensity in adult specimens (501 vs. 1734) while in beetles found on the horse endurance track, larval burdens were comparable (548 vs. 858). The results suggest that S. cristatus become infected at the camel milk farm, and in search for other sources of food, they fly to places where they were found feeding on feces of other animals.
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Camelus/parasitologia , Besouros/parasitologia , Nematoides/fisiologia , Infecções por Nematoides/veterinária , Animais , Fezes/parasitologia , Larva , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/transmissão , Emirados Árabes Unidos/epidemiologiaRESUMO
Cats are host to dipylidiid cestodes of the genera Diplopylidium, Dipylidium and Joyeuxiella. Broadline(®), a topical broad-spectrum combination parasiticide containing fipronil (8.3 % w/v), (S)-methoprene (10 % w/v), eprinomectin (0.4 % w/v) and the cestocide praziquantel (8.3 % w/v), has previously been shown to be efficacious against Dipylidium caninum and Diplopylidium spp. in cats. To evaluate its efficacy against Joyeuxiella species, a blinded clinical efficacy study was conducted according to GCP. All cats had evidence for naturally acquired dipylidiid cestode infection as confirmed by pre-treatment examination. Cats were allocated randomly to two groups of 13 cats each based on bodyweight: Control (untreated) and Broadline(®) at 0.12 mL/kg bodyweight administered once topically. Based on the comparison of helminth counts in the treated and untreated cats seven days post treatment, Broadline(®) demonstrated >99 % efficacy (p < 0.01) against mature J. fuhrmanni and J. pasqualei, with 11 and 13 of the untreated cats harbouring 1 to 102 or 2 to 95 cestodes, respectively. In addition, parasite counts indicated 95.9 % efficacy (p = 0.006) against the rictularoid nematode Pterygodermatites cahirensis.
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Anticestoides/uso terapêutico , Doenças do Gato/tratamento farmacológico , Infecções por Cestoides/veterinária , Ivermectina/análogos & derivados , Metoprene/uso terapêutico , Praziquantel/uso terapêutico , Pirazóis/uso terapêutico , Animais , Anticestoides/administração & dosagem , Doenças do Gato/parasitologia , Gatos , Cestoides , Infecções por Cestoides/tratamento farmacológico , Quimioterapia Combinada , Feminino , Ivermectina/administração & dosagem , Ivermectina/uso terapêutico , Masculino , Metoprene/administração & dosagem , Praziquantel/administração & dosagem , Pirazóis/administração & dosagemRESUMO
Oocysts of a coccidian morphologically matching features of Caryospora megafalconis Klüh, 1994 were found in fecal samples and contents of the large intestines in five wild caught Clamydotis macqueenii (Gray) and 19 captive bred C. undulata (Jaquin). Scrapings of the intestinal mucosa of necropsied birds revealed macrogamonts and unsporulated oocysts. Sporulation in a potassium dichromate solution at 26 °C was completed in 48 h. Intestinal contents and sporulated oocysts obtained from feces of infected bustards as well as sporulated oocysts of C. megafalconis and C. neofalconis Böer, 1982 from two Falco rusticolis Linnaeus and one F. peregrinus Tunstall were used for DNA sequencing of the cox1, 18S ribosomal ribonucleic acid (rRNA), and 28S rRNA genes. The phylogenetic trees for all three genes showed that sequences of the material from bustards were identical with C. megafalconis from falcons. C. neofalconis and C. daceloe Yang et al., 2014 were situated in the neighboring clades. Contrary to this, subsequent sequences of C. bigenetica Wacha and Christiansen, 1982 from rattlesakes are at a distinct distance suggesting that despite morphological similarities of the oocysts, there are differences between Caryospora species of birds and reptiles. For this reason, it might be reasonable to transfer avian Caryospora species into a new genus Avispora.
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Aves/parasitologia , Eimeriidae/isolamento & purificação , Animais , Eimeriidae/classificação , Fezes , Feminino , Masculino , Oocistos , Filogenia , RNA Ribossômico 18S , RNA Ribossômico 28SRESUMO
We measured the heat which is reversibly exchanged during the course of an electrochemical surface reaction, i.e., the deposition/dissolution of the first two monolayers of Ag on a Au(111) surface in (bi)sulfate and perchlorate containing electrolytes. The reversibly exchanged heat corresponds to the Peltier heat of the reaction and is linearly related to its entropy change, including also non-Faradaic side processes. Hence, the measurement of the Peltier heat provides thermodynamic information on the electrochemical processes which is complementary to the current-potential relations usually obtained by conventional electrochemical methods. From the variation of the molar Peltier heat during the various stages of the deposition reaction we inferred that co-adsorption processes of anions and Ag do not play a prominent role, while we find strong indications for a charge neutral substitution reaction of adsorbed anions by hydroxide, which would not show up in cyclic voltammetry.
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The life cycle of Physocephalus dromedarii was studied under experimental conditions. Larvae obtained from naturally infected Scarabaeus cristatus and Aphodius sp. (Coleoptera: Scarabaeidae) were measured and examined in light and scanning electron microscopy and used to infect a dromedary as final host as well as chicken, mice and a toad as possible paratenic hosts. Larvae with the same morphology and similar measurements were found in naturally infected reptiles (Trapelus flavimaculatus, Eryx jayakari, Cerastes gasperettii). Body length of examined larvae varied between 1450 and 1700 µm. Dorsal, ventral and lateral lips, peg-like papillae and amphideal pits are located on the cephalic cone. There are two asymmetrical cervical deirids, long simple lateral wings and a knob-like posterior end covered with minute spines. In the camel, patency is reached within 12 weeks after infection while larvae in paratenic hosts migrate into the wall of the alimentary tract and become dormant.
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Camelus/parasitologia , Besouros/parasitologia , Infecções por Spirurida/parasitologia , Spiruroidea/fisiologia , Animais , Anuros , Galinhas , Feminino , Larva , Estágios do Ciclo de Vida , Masculino , Camundongos , Microscopia , Microscopia Eletrônica de Varredura , Spiruroidea/isolamento & purificação , Spiruroidea/ultraestruturaRESUMO
The aggregation of amphiphilic molecules (e.g., the formation of micelles or membranes) is usually entropy-driven. We use electrochemical microcalorimetry to directly determine the entropy change a dodecyl sulfate molecule experiences upon potential-induced adsorption from aqueous solution into a surface aggregate. From measurements of the heat, which is reversibly exchanged during the adsorption or desorption process, we determined a value of 37 ± 9 J/(mol K) for the aggregation entropy. This value is in accordance with entropies of micellization of dodecyl sulfate in solution. A comparison with estimates of the entropy of aggregation of dodecane in aqueous solutions reveals that the aggregation is driven by the entropic contribution of the hydrophobic hydrocarbon tail, in accordance with general models for the aggregation of amphiphilic molecules.
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Calorimetria/métodos , Eletroquímica/métodos , Dodecilsulfato de Sódio/química , EntropiaRESUMO
We investigated the thermodynamical properties of water exchanged in poly(l-glutamic acid)/poly(allylamine)hydrochloride (PGA/PAH) polyelectrolyte multilayers containing ferrocyanide. Oxidation/reduction of the ferrocyanide in the multilayer caused a reversible swelling/contraction of the film due to the uptake/release of counter ions and water. We used electrochemical quartz crystal microbalance and electrochemical microcalorimetry to correlate the amount of water with the accompanying entropy changes during electrochemical swelling of the multilayer for a series of different anions at different concentrations. The number of exchanged water molecules was highly dependent on the ionic strength and the type of anion in the buffer solution. However, the entropy change per exchanged water molecule was found to be independent of these two parameters. The water molecules in the polyelectrolyte multilayer have reduced the entropy compared to that of bulk water (≈-1 J mol(-1) K(-1)). A comparison of hydration entropies for free polyelectrolytes and PGA/PAH multilayers suggests that such systems are mainly stabilized by water release during multilayer construction.
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Delicate filamentous schistosomatids detected in the intestinal veins of experimentally infected chickens are here described as a new parasite species, Gigantobilharzia melanoidis, and details of its life cycle are given. It is the first complete description of a schistosome species that uses Melanoides tuberculata as an intermediate host. Apharyngeate ocellate brevifurcate cercariae found in 65 out of 950 M. tuberculata collected in a pond in Al Aweer, United Arab Emirates were used as infection material. The new species can be distinguished from the other species of the genus by the following combination of characters: caecal reunion in males situated anterior to seminal vesicle, a very short gynecophoric canal (gynecophoric canal length/body length ratio lower than 0.05) supported by 12-14 thickened bands. Cercariae of G. melanoidis can be distinguished from other Gigantobilharzia cercariae described in the literature based on the combination of these characters: flame cell formula 2[3 + 3 + (1)] = 14 and relatively longer tail stem in relation to body (tail stem length/body length ratio = 2). Under laboratory conditions at a temperature between 24 and 26 °C, M. tuberculata started to shed cercariae 7 weeks after exposure to miracidia. The prepatent period of G. melanoidis in experimentally infected chicken lasted between 43 and 49 days. The parasite inhabits the blood vessels mainly of the small intestine. Sections of adult worms and eggs were also found in histocuts of parenchymatous organs. Results of phylogenetic analysis corroborated that G. melanoidis is a distinct species; however, they also confirmed that the genus Gigantobilharzia is in need of revision and in future might be split into several genera.