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1.
Sci Rep ; 7: 46630, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28425457

RESUMO

In order to reduce the thermal conductivity of CoSbS, a newly developed thermoelectric semiconductor, we have aimed at intentionally induce atomic disorder in its structure. This endeavor was guided by Density Functional Theory(DFT) calculations which indicated that substituting sulfur with selenium might be easily achievable experimentally because of the low formation energy of this point defect. Thereby, CoSbS1-xSex compounds having 0 ≤ x ≤ 1 have been synthesized by solid state reaction. Besides the expected semiconducting paracostibite phase, we have observed the appearance of a semimetallic costibite phase, never reported experimentally before. This cross-fertilized theoretical and experimental approach allowed us to reduce by 50% the thermal conductivity of paracostibite and therefore reach a maximum zT of 0.62 at 730 K. This makes this entirely new CoSbS1-xSex alloy very attractive for further optimizations and potential usage in thermoelectric applications.

2.
J Phys Chem Lett ; 5(21): 3763-7, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26278747

RESUMO

Copper zinc tin sulfide-selenide, Cu2ZnSn(S1-xSex)4 (CZTSSe), thin film photovoltaic devices were fabricated using a fast and environmentally friendly preparation method, consisting of the following steps: An instantaneous synthesis of a Cu-Zn-Sn-S (no Se) colloid, a nonpyrolytic spray of a dispersion of this colloid in a water-ethanol mixture, and a sequential annealing first in a N2 atmosphere and second in a Se atmosphere. The achievement of cell efficiencies up to 8.6% under AM1.5G (cell area 0.25 cm(2)) and without antireflecting coating indicates that this method can compete with other vacuum-based or more complex wet deposition methods.

3.
J Clin Microbiol ; 51(3): 1014-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23269734

RESUMO

Glycopeptide-resistant Staphylococcus epidermidis (GRSE) strains are of increasing concern in bone and joint infections (BJIs). Using multilocus sequence typing and multilocus variable-number tandem repeat analysis, we show that BJI-associated GRSE strains are genetically diverse but arise from related, multiresistant hospital sequence types (STs), mostly ST2, ST5, and ST23.


Assuntos
Artrite/microbiologia , Farmacorresistência Bacteriana , Glicopeptídeos/farmacologia , Osteomielite/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/efeitos dos fármacos , Adulto , Idoso , Artrite/epidemiologia , Análise por Conglomerados , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Osteomielite/epidemiologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus epidermidis/classificação , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/isolamento & purificação
4.
Mol Ecol ; 19(23): 5296-307, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21040055

RESUMO

Mating with attractive or dominant males is often predicted to offer indirect genetic benefits to females, but it is still largely unclear how important such non-random mating can be with regard to embryo viability. We sampled a natural population of adult migratory brown trout (Salmo trutta), bred them in vitro in a half-sib breeding design to separate genetic from maternal environmental effects, raised 2098 embryos singly until hatching, and exposed them experimentally to different levels of pathogen stress at a late embryonic stage. We found that the embryos' tolerance to the induced pathogen stress was linked to the major histocompatibility complex (MHC) of their parents, i.e. certain MHC genotypes appeared to provide better protection against infection than others. We also found significant additive genetic variance for stress tolerance. Melanin-based dark skin patterns revealed males with 'good genes', i.e. embryos fathered by dark coloured males had a high tolerance to infection. Mating with large and dominant males would, however, not improve embryo viability when compared to random mating. We used simulations to provide estimates of how mate choice based on MHC or melanin-based skin patterns would influence embryos' tolerance to the experimentally induced pathogen stress.


Assuntos
Reprodução/genética , Comportamento Sexual Animal , Truta/genética , Animais , Tamanho Corporal , Simulação por Computador , Feminino , Aptidão Genética , Complexo Principal de Histocompatibilidade/genética , Masculino , Melaninas/genética , Modelos Estatísticos , Análise de Sequência de DNA , Estresse Fisiológico , Truta/embriologia
5.
J Clin Microbiol ; 48(4): 1428-31, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20164270

RESUMO

We studied 315 coagulase-negative Staphylococcus strains recovered prospectively during 240 surgical procedures (206 subjects) from proven or suspected device-associated bone and joint infections. Sixteen strains (5.1%) had decreased susceptibility to glycopeptides: 15 (12 S. epidermidis strains, 2 S. capitis strains, and 1 S. haemolyticus strain) to teicoplanin alone (MIC of 16 mg/liter, n = 9; MIC of 32 mg/liter, n = 6) and one (S. epidermidis) to both teicoplanin and vancomycin (MIC, 16 and 8 mg/liter, respectively). Decreased susceptibility to teicoplanin was more prevalent in "infecting" strains (i.e., strains recovered from >/=2 distinct intraoperative samples) than in "contaminants" (i.e., strains not fulfilling this criterion) (8.1% [12/149] versus 2.4% [4/166], respectively [P = 0.022]). One hundred percent (13/13) of S. epidermidis strains with decreased susceptibility to teicoplanin were resistant to methicillin (versus 112/173 [64.7%] for S. epidermidis strains susceptible to teicoplanin; P = 0.021).


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/efeitos dos fármacos , Teicoplanina/farmacologia , Vancomicina/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Coagulase/biossíntese , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Staphylococcus/enzimologia , Adulto Jovem
6.
J Morphol ; 271(4): 383-93, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20101728

RESUMO

Mating plugs occluding the female gonopore after mating are a widespread phenomenon. In scorpions, two main types of mating plugs are found: sclerotized mating plugs being parts of the spermatophore that break off during mating, and gel-like mating plugs being gelatinous fluids that harden in the female genital tract. In this study, the gel-like mating plug of Euscorpius italicus was investigated with respect to its composition, fine structure, and changes over time. Sperm forms the major component of the mating plug, a phenomenon previously unknown in arachnids. Three parts of the mating plug can be distinguished. The part facing the outside of the female (outer part) contains sperm packages containing inactive spermatozoa. In this state, sperm is transferred. In the median part, the sperm packages get uncoiled to single spermatozoa. In the inner part, free sperm is embedded in a large amount of secretions. Fresh mating plugs are soft gelatinous, later they harden from outside toward inside. This process is completed after 3-5 days. Sperm from artificially triggered spermatophores could be activated by immersion in insect Ringer's solution indicating that the fluid condition in the females' genital tract or females' secretions causes sperm activation. Because of the male origin of the mating plug, it has likely evolved under sperm competition or sexual conflict. As females refused to remate irrespective of the presence or absence of a mating plug, females may have changed their mating behavior in the course of evolution from polyandry to monandry.


Assuntos
Escorpiões/metabolismo , Comportamento Sexual Animal/fisiologia , Espermatozoides/metabolismo , Animais , Feminino , Inseminação , Masculino , Escorpiões/citologia , Escorpiões/ultraestrutura , Espermatozoides/citologia , Espermatozoides/ultraestrutura , Fatores de Tempo
7.
Fish Shellfish Immunol ; 26(3): 531-5, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19232394

RESUMO

Juvenile or adult fish can alter their behaviour and rely on an innate and adaptive immune system to avoid/counteract pathogens, while fish embryos have to depend on egg characteristics and may be partly protected by their developing immune system that is building up from a certain age on. We developed an infection protocol that allows testing the reaction of individual whitefish embryos (Coregonus palaea) to repeated exposures to Pseudomonas fluorescens, an opportunistic bacterial fish pathogen. We used a full-factorial in vitro breeding design to separately test the effects of paternal and maternal contributions to the embryos' susceptibility to different kinds of pathogen exposure. We found that a first non-lethal exposure had immunosuppressive effects: pre-exposed embryos were more susceptible to future challenges with the same pathogen. At intermediate and high levels of pathogen intensity, maternal effects turned out to be crucial for the embryos' tolerance to infection. Paternal (i.e. genetic) effects played a significant role at the strongest level of infection, i.e. the embryos' own genetics already explained some of the variation in embryo susceptibility. Our findings suggest that whitefish embryos are largely protected by maternally transmitted substances, but build up some own innate immunocompetence several days before hatching.


Assuntos
Doenças dos Peixes/genética , Doenças dos Peixes/microbiologia , Infecções por Pseudomonas/veterinária , Pseudomonas fluorescens/fisiologia , Salmonidae/genética , Salmonidae/microbiologia , Animais , Cruzamento , Embrião não Mamífero/microbiologia , Doenças dos Peixes/mortalidade , Variação Genética , Infecções por Pseudomonas/genética , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/mortalidade
8.
Dis Aquat Organ ; 81(2): 119-25, 2008 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-18924376

RESUMO

In recent years, numerous cases of morphological gonadal alterations in fish have been recorded throughout the world and across a wide range of species. In the whitefish Coregonus fatioi from the pre-alpine Lake Thun (Switzerland), the frequency of gonadal alterations is particularly high and the variety of alteration types large. Little is known about the proximal causes and the direct consequences of these morphological features on population persistence. In particular, the potential for the observed alterations to be the phenotypic expression of reduced genetic quality has not yet been addressed. In this study, we used offspring survival during embryogenesis as a proximate indicator of male genetic quality and tested whether the presence of gonadal alterations in males is an indicator of reduced quality. Embryos resulted from in vitro fertilizations of gametes from 126 males and females. We found no significant correlation between embryo survival and gonadal alteration in adults. Our findings suggest that in C. fatioi of Lake Thun, alterations in gonad morphology are not a phenotypic expression of variation in genetic quality.


Assuntos
Anormalidades Congênitas/veterinária , Doenças dos Peixes/epidemiologia , Gônadas/anormalidades , Salmonidae/anormalidades , Animais , Anormalidades Congênitas/epidemiologia , Transtornos do Desenvolvimento Sexual/patologia , Transtornos do Desenvolvimento Sexual/veterinária , Embrião não Mamífero , Feminino , Doenças dos Peixes/patologia , Água Doce , Masculino , Salmonidae/genética , Suíça/epidemiologia
9.
Proc Biol Sci ; 275(1644): 1737-44, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18445560

RESUMO

'Good-genes' models of sexual selection predict significant additive genetic variation for fitness-correlated traits within populations to be revealed by phenotypic traits. To test this prediction, we sampled brown trout (Salmo trutta) from their natural spawning place, analysed their carotenoid-based red and melanin-based dark skin colours and tested whether these colours can be used to predict offspring viability. We produced half-sib families by in vitro fertilization, reared the resulting embryos under standardized conditions, released the hatchlings into a streamlet and identified the surviving juveniles 20 months later with microsatellite markers. Embryo viability was revealed by the sires' dark pigmentation: darker males sired more viable offspring. However, the sires' red coloration correlated negatively with embryo survival. Our study demonstrates that genetic variation for fitness-correlated traits is revealed by male colour traits in our study population, but contrary to predictions from other studies, intense red colours do not signal good genes.


Assuntos
Carotenoides/fisiologia , Melaninas/fisiologia , Pigmentação/fisiologia , Truta/embriologia , Animais , Feminino , Variação Genética , Masculino , Estatísticas não Paramétricas , Truta/genética , Truta/crescimento & desenvolvimento
10.
Genetica ; 134(1): 21-30, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18327648

RESUMO

Some models of sexual selection predict that individuals vary in their genetic quality and reveal some of this variation in their secondary sexual characteristics. Alpine whitefish (Coregonus sp.) develop breeding tubercles shortly before their spawning season. These tubercles are epidermal structures that are distributed regularly along the body sides of both males and females. There is still much unexplained variation in the size of breeding tubercles within both sexes and with much overlap between the sexes. It has been suggested that breeding tubercles function to maintain body contact between the mating partners during spawning, act as weapons for defence of spawning territories, or are sexual signals that reveal aspects of genetic quality. We took two samples of whitefish from their spawning place, one at the beginning and one around the peak of spawning season. We found that females have on average smaller breeding tubercles than males, and that tubercle size partly reveals the stage of gonad maturation. Two independent full-factorial breeding experiments revealed that embryo mortality was significantly influenced by male and female effects. This finding demonstrates that the males differed in their genetic quality (because offspring get nothing but genes from their fathers). Tubercle size was negatively linked to some aspects of embryo mortality in the first breeding experiment but not significantly so in the second. This lack of consistency adds to inconsistent results that were reported before and suggests that (i) some aspects of genetic quality are not revealed in breeding tubercles while others are, or (ii) individuals vary in their signaling strategies and the information content of breeding tubercles is not always reliable. Moreover, the fact that female whitefish have breeding tubercles of significant size while males seem to have few reasons to be choosy suggests that the tubercles might also serve some functions that are not linked to sexual signaling.


Assuntos
Cruzamento , Salmonidae/genética , Comportamento Sexual Animal , Animais , Copulação , Feminino , Genes , Variação Genética , Heterozigoto , Masculino , Preferência de Acasalamento Animal , Reprodução , Salmonidae/embriologia , Estações do Ano , Seleção Genética , Caracteres Sexuais
11.
J Clin Microbiol ; 46(4): 1556-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18287323

RESUMO

We report a case of prosthetic hip infection due to Tropheryma whipplei in a 74-year-old man not previously known to have Whipple's disease. Diagnosis was based on systematic 16S rRNA gene amplification and sequencing of samples obtained during revision hip arthroplasty.


Assuntos
Bioprótese/efeitos adversos , Prótese de Quadril/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , Tropheryma/isolamento & purificação , Doença de Whipple/diagnóstico , Idoso , Humanos , Masculino , Reação em Cadeia da Polimerase , Infecções Relacionadas à Prótese/microbiologia , Tropheryma/classificação , Tropheryma/genética , Doença de Whipple/microbiologia
12.
J Shoulder Elbow Surg ; 17(4): 616-23, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18276165

RESUMO

Operative treatment of suprascapular nerve entrapment consists of decompression of the nerve, either at the suprascapular notch or the spinoglenoid notch. The aim of this study was to describe new arthroscopic portals to approach these 2 notches at the same time. Twenty shoulders in 10 fresh frozen cadavers were investigated. Four portals were used in line with the scapular spine (S1, S2, S3, S4). The suprascapular pedicle was visualized passing under the supraspinatus muscle. The technique was performed for each specimen. The efficacy and safety of the technique were assessed by open dissection. No injury to the nerve was identified after performing the technique. Decompression was complete in 18 of 20 cases at the suprascapular notch and in all cases at the spinoglenoid notch. With this technique, arthroscopic decompression of the nerve at the suprascapular and spinoglenoid notches is anatomically possible.


Assuntos
Artroscopia/métodos , Síndromes de Compressão Nervosa/cirurgia , Nervos Periféricos/cirurgia , Articulação do Ombro/anatomia & histologia , Cadáver , Descompressão Cirúrgica/métodos , Humanos , Nervos Periféricos/anatomia & histologia , Escápula/anatomia & histologia , Articulação do Ombro/inervação
13.
Genetica ; 132(2): 199-208, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17628755

RESUMO

Some models of sexual selection predict that individuals vary in their genetic quality and reveal some of this variation in their secondary sexual characteristics. Alpine whitefish (Coregonus sp.) develop breeding tubercles shortly before their spawning season. These tubercles are epidermal structures that are distributed regularly along the body sides of both males and females. There is still much unexplained variation in the size of breeding tubercles within both sexes and with much overlap between the sexes. It has been suggested that breeding tubercles function to maintain body contact between the mating partners during spawning, act as weapons for defence of spawning territories, or are sexual signals that reveal aspects of genetic quality. We took two samples of whitefish from their spawning place, one at the beginning and one around the peak of spawning season. We found that females have on average smaller breeding tubercles than males, and that tubercle size partly reveals the stage of gonad maturation. Two independent full-factorial breeding experiments revealed that embryo mortality was significantly influenced by male and female effects. This finding demonstrates that the males differed in their genetic quality (because offspring get nothing but genes from their fathers). Tubercle size was negatively linked to some aspects of embryo mortality in the first breeding experiment but not significantly so in the second. This lack of consistency adds to inconsistent results that were reported before and suggests that (i) some aspects of genetic quality are not revealed in breeding tubercles while others are, or (ii) individuals vary in their signaling strategies and the information content of breeding tubercles is not always reliable. Moreover, the fact that female whitefish have breeding tubercles of significant size while males seem to have few reasons to be choosy suggests that the tubercles might also serve some functions that are not linked to sexual signaling.


Assuntos
Reprodução/fisiologia , Salmonidae/genética , Salmonidae/fisiologia , Estações do Ano , Animais , Cruzamento , Embrião não Mamífero/embriologia , Feminino , Variação Genética , Masculino , Preferência de Acasalamento Animal/fisiologia , Tamanho do Órgão , Salmonidae/anatomia & histologia , Salmonidae/embriologia , Caracteres Sexuais , Taxa de Sobrevida
14.
BMC Evol Biol ; 7: 207, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17974038

RESUMO

BACKGROUND: Males that are successful in intra-sexual competition are often assumed to be of superior quality. In the mating system of most salmonid species, intensive dominance fights are common and the winners monopolise most mates and sire most offspring. We drew a random sample of mature male brown trout (Salmo trutta) from two wild populations and determined their dominance hierarchy or traits linked to dominance. The fish were then stripped and their sperm was used for in vitro fertilisations in two full-factorial breeding designs. We recorded embryo viability until hatching in both experiments, and juvenile survival during 20 months after release into a natural streamlet in the second experiment. Since offspring of brown trout get only genes from their fathers, we used offspring survival as a quality measure to test (i) whether males differ in their genetic quality, and if so, (ii) whether dominance or traits linked to dominance reveal 'good genes'. RESULTS: We found significant additive genetic variance on embryo survival, i.e. males differed in their genetic quality. Older, heavier and larger males were more successful in intra-sexual selection. However, neither dominance nor dominance indicators like body length, weight or age were significantly linked to genetic quality measured as embryo or juvenile survival. CONCLUSION: We found no evidence that females can improve their offspring's genetic viability by mating with large and dominant males. If there still were advantages of mating with dominant males, they may be linked to non-genetic benefits or to genetic advantages that are context dependent and therefore possibly not revealed under our experimental conditions - even if we found significant additive genetic variation for embryo viability under such conditions.


Assuntos
Tamanho Corporal , Predomínio Social , Truta/genética , Envelhecimento , Animais , Feminino , Masculino , Reprodução , Truta/anatomia & histologia
15.
Infect Control Hosp Epidemiol ; 28(10): 1169-74, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17828694

RESUMO

OBJECTIVE: Femoral neck fracture is the most frequent orthopedic emergency among elderly persons. Despite a high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage in this population, no multicenter study of antibiotic prophylaxis practices and the rate and microbiological characteristics of surgical site infection (SSI) has been performed in France. DESIGN: Retrospective, multicenter cohort study. SETTING: Twenty-two university and community hospitals in France. PATIENTS: Each center provided data on 25 consecutive patients who underwent surgery for femoral neck fracture during the first quarter of 2005. Demographic, clinical, and follow-up characteristics were recorded, and most patients had a follow-up office visit or were involved in a telephone survey 1 year after surgery. RESULTS: These 22 centers provided data on 541 patients, 396 (73%) of whom were followed up 1 year after surgery. Of 504 (93%) patients for whom antibiotic prophylaxis was recorded, 433 (86%) received a cephalosporin. Twenty-two patients had an SSI, for a rate of 5.6% (95% confidence interval, 3.7-8.0). SSI was reported for 15 (6.9%) of patients who had a prosthesis placed and for 7 (3.9%) who underwent osteosynthesis (P=.27). SSI was diagnosed a median of 30 days after surgery (interquartile range, 21-41 days); 7 (32%) of these SSIs were superficial infections, and 15 (68%) were deep or organ-space infections. MRSA caused 7 SSIs (32%), Pseudomonas aeruginosa caused 5 (23%), other staphylococci caused 4 (18%), and other bacteria caused 2 (9%); the etiologic pathogen was unknown in 4 cases (18%). Reoperation was performed for 14 patients with deep or organ-space SSI, including 6 of 7 patients with MRSA SSI. The mortality rate 1 year after surgery was 20% overall but 50% among patients with SSI. In univariate analysis, only the National Nosocomial Infections Surveillance System risk index score was significantly associated with SSI (P=.006). CONCLUSIONS: SSI after surgery for femoral neck fracture is severe, and MRSA is the most frequently encountered etiologic pathogen. A large, multicenter prospective trial is necessary to determine whether the use of antibiotic prophylaxis effective against MRSA would decrease the SSI rate in this population.


Assuntos
Infecção Hospitalar/mortalidade , Fraturas do Colo Femoral/cirurgia , Procedimentos Ortopédicos/efeitos adversos , Infecção da Ferida Cirúrgica/mortalidade , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Infecção Hospitalar/microbiologia , França/epidemiologia , Humanos , Resistência a Meticilina , Procedimentos Ortopédicos/estatística & dados numéricos , Prevalência , Estudos Retrospectivos , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/patogenicidade , Infecção da Ferida Cirúrgica/microbiologia
16.
J Morphol ; 267(2): 166-86, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16276493

RESUMO

The female genital organs of the tetrablemmid Indicoblemma lannaianum are astonishingly complex. The copulatory orifice lies anterior to the opening of the uterus externus and leads into a narrow insertion duct that ends in a genital cavity. The genital cavity continues laterally in paired tube-like copulatory ducts, which lead into paired, large, sac-like receptacula. Each receptaculum has a sclerotized pore plate with associated gland cells. Paired small fertilization ducts originate in the receptacula and take their curved course inside the copulatory ducts. The fertilization ducts end in slit-like openings in the sclerotized posterior walls of the copulatory ducts. Huge masses of secretions forming large balls are detectable in the female receptacula. An important function of these secretory balls seems to be the encapsulation of spermatozoa in discrete packages in order to avoid the mixing of sperm from different males. In this way, sperm competition may be completely prevented or at least severely limited. Females seem to have full control over transferred sperm and be able to express preference for spermatozoa of certain males. The lumen of the sperm containing secretory balls is connected with the fertilization duct. Activated spermatozoa are only found in the uterus internus of females, which is an indication of internal fertilization. The sperm cells in the uterus internus are characterized by an extensive cytoplasm and an elongated, cone-shaped nucleus. The male genital system of I. lannaianum consists of thick testes and thin convoluted vasa deferentia that open into the wide ductus ejaculatorius. The voluminous globular palpal bulb is filled with seminal fluid consisting of a globular secretion in which only a few spermatozoa are embedded. The spermatozoa are encapsulated by a sheath produced in the genital system. The secretions in females may at least partly consist of male secretions that could be involved in the building of the secretory balls or play a role in sperm activation. The male secretions could also afford nutriments to the spermatozoa.


Assuntos
Aranhas/anatomia & histologia , Aranhas/fisiologia , Animais , Copulação , Estudos Transversais , Feminino , Fertilização , Genitália/fisiologia , Genitália/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Modelos Biológicos , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura
17.
J Morphol ; 260(1): 72-84, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15052598

RESUMO

The structure and function of the spermatophore of Euscorpius italicus are analyzed. We show how the spermatophore gets shaped from two hemispermatophores and for the first time the sperm transfer mechanism is shown in detail, illustrating function and importance of all complex lobe structures of an euscorpiid spermatophore. A detailed description of the interaction of spermatophore and female genitalia is given. The capsular region of the spermatophore bears different lobes: The distal and basal lobes hook into two cavities on the inner side of the female's genital operculum. A so-called "crown-like structure" hooks into a membranous area in the genital atrium. During sperm transfer, these crown-like structures move backwards, in this way widening the female's genital opening. The sperm duct of the spermatophore is coated with numerous spicules on its outer side, which could serve as a sealing mechanism and/or may stimulate the female. Furthermore, we conclude that "safeguarding of sperm transfer" is one driving force for evolution of male genital complexity in scorpions, but also sexual selection by cryptic female choice could partly play a role.


Assuntos
Genitália Feminina/ultraestrutura , Genitália Masculina/ultraestrutura , Escorpiões/citologia , Animais , Comportamento Animal/fisiologia , Copulação/fisiologia , Feminino , Genitália Feminina/fisiologia , Genitália Masculina/fisiologia , Masculino , Microscopia Eletrônica de Varredura , Escorpiões/fisiologia , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura
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