WorldWideScience

Sample records for autonomously sustains spermatogenesis

  1. Throughput Evaluation of an Autonomous Sustainment Cargo Container System

    National Research Council Canada - National Science Library

    Yeh, Mingtze

    2007-01-01

    .... Autonomous containers will play an essential role in the ability to deliver logistical supplies to waterborne littoral vessels enabling them to maintain station and complete there military operations...

  2. [Sustainability focus in the health plans of the autonomous communities: sustainable development as an opportunity].

    Science.gov (United States)

    Moyano-Santiago, Miguel A; Rivera-Lirio, Juana M

    2016-01-01

    To determine the degree to which the health plans of the autonomous communities focus on the usual three dimensions of sustainability: economic, social and environmental, both in the general level of discourse and in the different areas of intervention. A qualitative study was conducted through content analysis of a large sample of documents. The specific methodology was analysis of symbolic and operational sensitivity in a sample of eleven health plans of the Spanish state. Social aspects, such as social determinants or vulnerable groups, are receiving increasing attention from the health planner, although there is room to strengthen attention to environmental issues and to provide specific interventions in economic terms. The analysis demonstrates the incipient state of health plans as strategic planning documents that integrate economic, social and environmental aspects and contribute to the sustainability of the different health systems of the country. Copyright © 2016 SESPAS. Published by Elsevier Espana. All rights reserved.

  3. Not Deep Learning but Autonomous Learning of Open Innovation for Sustainable Artificial Intelligence

    Directory of Open Access Journals (Sweden)

    JinHyo Joseph Yun

    2016-08-01

    Full Text Available What do we need for sustainable artificial intelligence that is not harmful but beneficial human life? This paper builds up the interaction model between direct and autonomous learning from the human’s cognitive learning process and firms’ open innovation process. It conceptually establishes a direct and autonomous learning interaction model. The key factor of this model is that the process to respond to entries from external environments through interactions between autonomous learning and direct learning as well as to rearrange internal knowledge is incessant. When autonomous learning happens, the units of knowledge determinations that arise from indirect learning are separated. They induce not only broad autonomous learning made through the horizontal combinations that surpass the combinations that occurred in direct learning but also in-depth autonomous learning made through vertical combinations that appear so that new knowledge is added. The core of the interaction model between direct and autonomous learning is the variability of the boundary between proven knowledge and hypothetical knowledge, limitations in knowledge accumulation, as well as complementarity and conflict between direct and autonomous learning. Therefore, these should be considered when introducing the interaction model between direct and autonomous learning into navigations, cleaning robots, search engines, etc. In addition, we should consider the relationship between direct learning and autonomous learning when building up open innovation strategies and policies.

  4. Spermatogenesis and cryptorchidism

    Directory of Open Access Journals (Sweden)

    Giovanni eCobellis

    2014-05-01

    Full Text Available Cryptorchidism represents the most common endocrine disease in boys, with infertility more frequently observed in bilateral forms. It is also known that undescended testes, if untreated, lead to an increased risk of testicular tumors, usually seminomas, arising from mutant germ cells. In normal testes, germ cell development is an active process starting in the first months of life when the neonatal gonocytes transform into adult dark spermatogonia. These cells are now thought to be the stem cells useful to support spermatogenesis. Several researches suggest that adult dark spermatogonia form between 3 and 9 months of age. Not all the neonatal gonocytes transform into adult dark spermatogonia; indeed, the residual gonocytes undergo involution by apoptosis. In the undescended testes, these transformations are inhibited leading to a deficient pool of stem cells for post pubertal spermatogenesis. Early surgical intervention in infancy may allow the normal development of stem cells for spermatogenesis.Moreover it is very interesting to note that intra-tubular carcinoma in situ in the second and third decades have enzymatic markers similar to neonatal gonocytes suggesting that these cells fail transformation into adult dark spermatogonia and likely generate testicular cancer in cryptorchid men. Orchidopexy between 6 and 12 months of age is recommended to maximize the future fertility potential and decrease the testicular cancer risk in adulthood.

  5. A role for primate subgenual cingulate cortex in sustaining autonomic arousal.

    Science.gov (United States)

    Rudebeck, Peter H; Putnam, Philip T; Daniels, Teresa E; Yang, Tianming; Mitz, Andrew R; Rhodes, Sarah E V; Murray, Elisabeth A

    2014-04-08

    The subgenual anterior cingulate cortex (subgenual ACC) plays an important role in regulating emotion, and degeneration in this area correlates with depressed mood and anhedonia. Despite this understanding, it remains unknown how this part of the prefrontal cortex causally contributes to emotion, especially positive emotions. Using Pavlovian conditioning procedures in macaque monkeys, we examined the contribution of the subgenual ACC to autonomic arousal associated with positive emotional events. After such conditioning, autonomic arousal increases in response to cues that predict rewards, and monkeys maintain this heightened state of arousal during an interval before reward delivery. Here we show that although monkeys with lesions of the subgenual ACC show the initial, cue-evoked arousal, they fail to sustain a high level of arousal until the anticipated reward is delivered. Control procedures showed that this impairment did not result from differences in autonomic responses to reward delivery alone, an inability to learn the association between cues and rewards, or to alterations in the light reflex. Our data indicate that the subgenual ACC may contribute to positive affect by sustaining arousal in anticipation of positive emotional events. A failure to maintain positive affect for expected pleasurable events could provide insight into the pathophysiology of psychological disorders in which negative emotions dominate a patient's affective experience.

  6. Double spermatogenesis in Chelicerata.

    Science.gov (United States)

    Alberti, Gerd

    2005-12-01

    Sperm dimorphism is a rare phenomenon in Chelicerata. Until now, it was known only from three species of the opilionid genus Siro (Sironidae, Cyphophthalmi). Fertilizing (eusperm) and nonfertilizing spermatozoa (parasperm) develop in the same cyst and are thus sister cells. The fine structure of the spermatozoa of two species has been examined and is compared here. In contrast to Siro rubens, S. duricorius spermatozoa lack an acrosomal complex. Both sperm types produce a transitional process, a more or less modified flagellum, which is later retracted. Hence, the spermatozoa are aflagellate. Eusperm and parasperm of all three species form highly ordered sperm balls that are stored in the deferent duct. Reviewing and adding new results about the sperm dimorphism in this arachnid taxon provides the basis for some considerations of another enigmatic morphological character found in Uropygi and Amblypygi, i.e., the tubular accessory genital glands that show holocrine extrusion. These glands are suggested to represent modified, infertile derivatives of the testis anlage. Their secretion is produced in a way reminiscent of a strongly degenerated spermatogenesis. Consequently, these products may be regarded as strongly degenerated germ cells representing a line of germ cell development, which has been separated very early in spermatogenesis from the usual line leading to fertilizing sperm cells. This further, although less evident, case of probable dichotomous germ cell development is discussed with respect to the controversial phylogenetic-systematic relationships between Uropygi (Thelyphonida and Schizomida), Amblypygi, and Araneae. Copyright 2005 Wiley-Liss, Inc.

  7. Augmented Reality: Sustaining Autonomous Way-Finding in the Community for Older Persons with Cognitive Impairment.

    Science.gov (United States)

    Sejunaite, K; Lanza, C; Ganders, S; Iljaitsch, A; Riepe, M W

    2017-01-01

    Impairment of autonomous way-finding subsequent to a multitude of neurodegenerative and other diseases impedes independence of older persons and their everyday activities. It was the goal to use augmented reality to aid autonomous way-finding in a community setting. A spatial map and directional information were shown via head-up display to guide patients from the start zone on the hospital campus to a bakery in the nearby community. Hospital campus and nearby community. Patients with mild cognitive impairment (age 63 to 89). A head-up display was used to help patients find their way. Time needed to reach goal and number of assists needed. With use of augmented reality device, patients preceded along the correct path in 113 out of 120 intersections. Intermittent reassurance was needed for most patients. Patients affirmed willingness to use such an augmented reality device in everyday life if needed or even pay for it. Augmented reality guided navigation is a promising means to sustain autonomous way-finding as a prerequisite for autonomy of older persons in everyday activities. Thus, this study lays ground for a field trial in the community using assistive technology for older persons with cognitive impairment.

  8. Transitioning Submersible Chemical Analyzer Technologies for Sustained, Autonomous Observations From Profiling Moorings, Gliders and other AUVs

    National Research Council Canada - National Science Library

    Hanson, Alfred K; Donaghay, Percy L; Moore, Casey; Arrieta, Richard

    2006-01-01

    The long term goal is to transition existing prototype autonomous profiling nutrient analyzers into commercial products that can be readily deployed on autonomous profiling moorings, coastal gliders...

  9. Transitioning Submersible Chemical Analyzer Technologies for Sustained, Autonomous Observations from Profiling Moorings, Gliders and other AUVs

    National Research Council Canada - National Science Library

    Hanson, Alfred K; Donaghay, Percy L; Moore, Casey; Arrieta, Richard

    2005-01-01

    The long term goal is to transition existing prototype autonomous profiling nutrient analyzers into commercial products that can be readily deployed on autonomous profiling moorings, coastal gliders...

  10. Study of intra testicular regulations of spermatogenesis ...

    African Journals Online (AJOL)

    Study of intra testicular regulations of spermatogenesis differentiation by ex-vivo approach. A Adaika, B Barenton, P Durand. Abstract. The aim of this work is to study the regulation of intratesticular during spermatogenesis ex vivo. To highlight the progress of spermatogenesis ex vivo, we developed two cell culture systems ...

  11. aqueous root extract on spermatogenesis

    African Journals Online (AJOL)

    spermatogenic activity similar to that of the whole plant which was shown previously to inhibit spermatogenesis. Methods: T. officinale aqueous extract was prepared by soaking 100 g of dried materials in 1 L distilled water for two days at 45 oC. Fifty adult ...

  12. A Seakeeping Study on the Autonomous Sustainment Cargo Container Delivery System

    National Research Council Canada - National Science Library

    Hedderly, James W

    2008-01-01

    .... Autonomous containers will play an essential role to deliver logistical supplies to waterborne littoral vessels in order to maintain station and complete military operations all while eliminating...

  13. The endocannabinoid system and spermatogenesis

    Directory of Open Access Journals (Sweden)

    Paola eGrimaldi

    2013-12-01

    Full Text Available AbstractSpermatogenesis is a complex process in which male germ cells undergo a mitotic phase followed by meiosis and by a morphogenetic process to form mature spermatozoa. Spermatogenesis is under the control of gonadotropins, steroid hormones and it is modulated by a complex network of autocrine and paracrine factors. These modulators ensure the correct progression of germ cell differentiation to form mature spermatozoa. Recently, it has been pointed out the relevance of endocannabinoids as critical modulators of male reproduction. Endocannabinoids are natural lipids able to bind to cannabinoid receptors and whose levels are regulated by specific biosynthetic and degradative enzymes. Together with their receptors and metabolic enzymes, they form the endocannabinoid system (ECS. In male reproductive tracts, they affect Sertoli cell activities, Leydig cell proliferation, germ cell differentiation, sperm motility, capacitation and acrosome reaction. The ECS interferes with the pituitary-gonadal axis, and an intricate crosstalk between ECS and steroid hormones has been highlighted. This mini-review will focus on the involvement of the ECS in the control of spermatogenesis and on the interaction between ECS and steroid hormones.

  14. Autonomous Vehicles for Smart and Sustainable Cities: An In-Depth Exploration of Privacy and Cybersecurity Implications

    Directory of Open Access Journals (Sweden)

    Hazel Si Min Lim

    2018-04-01

    Full Text Available Amidst rapid urban development, sustainable transportation solutions are required to meet the increasing demands for mobility whilst mitigating the potentially negative social, economic, and environmental impacts. This study analyses autonomous vehicles (AVs as a potential transportation solution for smart and sustainable development. We identified privacy and cybersecurity risks of AVs as crucial to the development of smart and sustainable cities and examined the steps taken by governments around the world to address these risks. We highlight the literature that supports why AVs are essential for smart and sustainable development. We then identify the aspects of privacy and cybersecurity in AVs that are important for smart and sustainable development. Lastly, we review the efforts taken by federal governments in the US, the UK, China, Australia, Japan, Singapore, South Korea, Germany, France, and the EU, and by US state governments to address AV-related privacy and cybersecurity risks in-depth. Overall, the actions taken by governments to address privacy risks are mainly in the form of regulations or voluntary guidelines. To address cybersecurity risks, governments have mostly resorted to regulations that are not specific to AVs and are conducting research and fostering research collaborations with the private sector.

  15. Spermatogenesis and testicular tumours in ageing dogs

    NARCIS (Netherlands)

    Peters, M. A.; de rooij, D. G.; Teerds, K. J.; van de Gaag, I.; van Sluijs, F. J.

    2001-01-01

    The aims of this investigation were to quantify the changes in canine spermatogenesis that occur during ageing and to study the prevalence of testicular tumours and their effects on spermatogenesis in dogs. Testes from 74 dogs of various breeds without clinically detected testicular disease and from

  16. Spermatogenesis and testicular tumours in ageing dogs

    NARCIS (Netherlands)

    Peters, M. A.; de rooij, D. G.; Teerds, K. J.; van der Gaag, I.; van Sluijs, F. J.

    2000-01-01

    Spermatogenesis was examined in testes from 74 dogs of various breeds without clinically detected testicular disease. A modified Johnsen score system was used to determine whether spermatogenesis deteriorates with ageing. The diameter of seminiferous tubules was measured in dogs without testicular

  17. Understanding spermatogenesis is a prerequisite for treatment

    Directory of Open Access Journals (Sweden)

    Schulze Wolfgang

    2003-11-01

    Full Text Available Abstract Throughout spermatogenesis multiplication, maturation and differentiation of germ cells results in the formation of the male gamete. The understanding of spermatogenesis needs detailed informations about the organization of the germinal epithelium, the structure and function of different types of germ cells, endocrine and paracrine cells and mechanisms, intratesticular and extratesticular regulation of spermatogenesis. Normal germ cells must be discriminated from malformed, apoptotic and degenerating germ cells and tumor cells. Identification of the border line between normal and disturbed spermatogenesis substantiate the diagnosis of impaired male fertility. The profound knowledge of the complicate process of spermatogenesis and all cells or cell systems involved with is the prerequisite to develop concepts for therapy of male infertility or to handle germ cells in the management of assisted reproduction.

  18. Effect of rejuvenation hormones on spermatogenesis.

    Science.gov (United States)

    Moss, Jared L; Crosnoe, Lindsey E; Kim, Edward D

    2013-06-01

    To review the current literature for the effect of hormones used in rejuvenation clinics on the maintenance of spermatogenesis. Review of published literature. Not applicable. Men who have undergone exogenous testosterone (T) and/or anabolic androgenic steroid (AAS) therapies. None. Semen analysis, pregnancy outcomes, and time to recovery of spermatogenesis. Exogenous testosterone and anabolic androgenic steroids suppress intratesticular testosterone production, which may lead to azoospermia or severe oligozoospermia. Therapies that protect spermatogenesis involve human chorionic gonadotropin (hCG) therapy and selective estrogen receptor modulators (SERMs). The studies examining the effect of human growth hormone (HGH) on infertile men are uncontrolled and unconvincing, but they do not appear to negatively impact spermatogenesis. At present, routine use of aromatase inhibitors is not recommended based on a lack of long-term data. The use of hormones for rejuvenation is increasing with the aging of the Baby Boomer population. Men desiring children at a later age may be unaware of the side-effect profile of hormones used at rejuvenation centers. Testosterone and anabolic androgenic steroids have well-established detrimental effects on spermatogenesis, but recovery may be possible with cessation. Clomiphene citrate, human growth hormone (HGH)/insulin-like growth factor-1 (IGF-1), human chorionic gonadotropin (hCG), and aromatase inhibitors do not appear to have significant negative effects on sperm production, but quality data are lacking. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  19. Spermatogenesis Abnormalities following Hormonal Therapy in Transwomen

    Directory of Open Access Journals (Sweden)

    Sirachai Jindarak

    2018-01-01

    Full Text Available Objective. To measure spermatogenesis abnormalities in transwomen at the time of sex reassignment surgery (SRS and to analyze the association between hormonal therapy duration and infertility severity. Design. Retrospective study. Setting. University hospital. Patients. One-hundred seventy-three transwomen who underwent SRS from January 2000 to December 2015. Interventions. All orchidectomy specimens were retrospectively reviewed and classified. History of hormonal therapy duration was retrieved from medical records. Main Outcome Measures. Histological examinations of orchidectomy specimens were performed to assess spermatogenesis. Results. One-hundred seventy-three orchidectomy specimens were evaluated. Histological examinations showed maturation arrest in 36.4%, hypospermatogenesis in 26%, Sertoli cell-only syndrome in 20.2%, normal spermatogenesis in 11%, and seminiferous tubule hyalinization in 6.4% of the specimens. Spermatogenesis abnormality severity was not associated with the total therapy duration (P=0.81 or patient age at the time of surgery (P=0.88. Testicular volumes and sizes were associated with spermatogenesis abnormality severity (P=0.001 and P=0.026, right testicle and left testicle, resp.. Conclusion(s. Feminizing hormonal treatment leads to reductions in testicular germ cell levels. All transwomen should be warned about this consequence, and gamete preservation should be offered before starting hormonal treatment.

  20. Miniaturized supercapacitors: key materials and structures towards autonomous and sustainable devices and systems

    Science.gov (United States)

    Soavi, Francesca; Bettini, Luca Giacomo; Piseri, Paolo; Milani, Paolo; Santoro, Carlo; Atanassov, Plamen; Arbizzani, Catia

    2016-09-01

    Supercapacitors (SCs) are playing a key role for the development of self-powered and self-sustaining integrated systems for different fields ranging from remote sensing, robotics and medical devices. SC miniaturization and integration into more complex systems that include energy harvesters and functional devices are valuable strategies that address system autonomy. Here, we discuss about novel SC fabrication and integration approaches. Specifically, we report about the results of interdisciplinary activities on the development of thin, flexible SCs by an additive technology based on Supersonic Cluster Beam Deposition (SCBD) to be implemented into supercapacitive electrolyte gated transistors and supercapacitive microbial fuel cells. Such systems integrate at materials level the specific functions of devices, like electric switch or energy harvesting with the reversible energy storage capability. These studies might open new frontiers for the development and application of new multifunction-energy storage elements.

  1. Inhibin B as a serum marker of spermatogenesis

    DEFF Research Database (Denmark)

    Jensen, T K; Andersson, A M; Hjollund, N H

    1997-01-01

    Recent studies have focused on reproductive health of men in the general population. However, semen samples are difficult to obtain within sampling frames that allow comparisons. Blood samples are easier to obtain than ejaculates. Therefore, serum biomarkers of spermatogenesis are of major intere...... reproductive health, may serve as a new marker of spermatogenesis, in addition to sperm concentration and serum FSH....... for population studies. FSH has previously been used as a marker of spermatogenesis, although it is also influenced by the hypothalamus. Serum inhibin B was recently suggested as a possible, more direct serum marker of spermatogenesis in men with testicular disorders. In a Danish nationwide collaborative study...

  2. Prespermatogenesis and early spermatogenesis in frogs.

    Science.gov (United States)

    Haczkiewicz, Katarzyna; Rozenblut-Kościsty, Beata; Ogielska, Maria

    2017-06-01

    Spermatogenesis in frogs was for the first time divided into two phases: prespermatogenesis, when gonocytes proliferate in developing tadpole testes, and active spermatogenesis when spermatogonial stem cells (i.e. descendants of gonocytes), either self-renew or enter into meiotic cycles within cysts formed by Sertoli cells. We argue that amphibian larval gonocytes are homologues to mammalian gonocytes, whereas spermatogonial stem cells (SSCs) in adult frogs are homologous to mammalian single spermatogonia (A s ). Gonocytes constitute sex cords, i.e. the precursors of seminiferous tubules; they are bigger than SSCs and differ in morphology and ultrastructure. The nuclear envelope in gonocytes formed deep finger-like invaginations absent in SSCs. All stages of male germ cells contained lipid droplets, which were surrounded by glycogen in SSCs, but not in gonocytes. Mitochondria in gonocytes had enlarged edges of cristae, and in SSCs also lamellar mitochondria appeared. Minimal duration of prespermatogenesis was 46days after gonadal sex differentiation, but usually it lasted longer. SSCs give rise to secondary spermatogonia (equal to mammalian A, In, and B). Their lowest number inside a cyst was eight and this indicated the minimal number of cell cycles (three) of secondary spermatogonia necessary to enter meiosis. We sorted them according to the number of cell cycles (from 8 to 256 cells). This number is similar to that recorded for mammals as the result of a single A s proliferation. The number of secondary spermatogonia correlates with the volume of a cyst. The general conclusion is that spermatogenesis in amphibians and mammals follows basically the same scheme. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. The somatosensory link in fibromyalgia: functional connectivity of the primary somatosensory cortex is altered by sustained pain and is associated with clinical/autonomic dysfunction.

    Science.gov (United States)

    Kim, Jieun; Loggia, Marco L; Cahalan, Christine M; Harris, Richard E; Beissner, Florian; Garcia, Ronald G; Kim, Hyungjun; Wasan, Ajay D; Edwards, Robert R; Napadow, Vitaly

    2015-05-01

    Fibromyalgia (FM) is a chronic functional pain syndrome characterized by widespread pain, significant pain catastrophizing, sympathovagal dysfunction, and amplified temporal summation for evoked pain. While several studies have demonstrated altered resting brain connectivity in FM, studies have not specifically probed the somatosensory system and its role in both somatic and nonsomatic FM symptoms. Our objective was to evaluate resting primary somatosensory cortex (S1) connectivity and to explore how sustained, evoked deep tissue pain modulates this connectivity. We acquired functional magnetic resonance imaging and electrocardiography data on FM patients and healthy controls during rest (the rest phase) and during sustained mechanical pressure-induced pain over the lower leg (the pain phase). Functional connectivity associated with different S1 subregions was calculated, while S1(leg) connectivity (representation of the leg in the primary somatosensory cortex) was contrasted between the rest phase and the pain phase and was correlated with clinically relevant measures in FM. During the rest phase, FM patients showed decreased connectivity between multiple ipsilateral and cross-hemispheric S1 subregions, which was correlated with clinical pain severity. Compared to the rest phase, the pain phase produced increased S1(leg) connectivity to the bilateral anterior insula in FM patients, but not in healthy controls. Moreover, in FM patients, sustained pain-altered S1(leg) connectivity to the anterior insula was correlated with clinical/behavioral pain measures and autonomic responses. Our study demonstrates that both somatic and nonsomatic dysfunction in FM, including clinical pain, pain catastrophizing, autonomic dysfunction, and amplified temporal summation, are closely linked with the degree to which evoked deep tissue pain alters S1 connectivity to salience/affective pain-processing regions. Additionally, diminished connectivity between S1 subregions during the rest

  4. The somatosensory link: S1 functional connectivity is altered by sustained pain and associated with clinical/autonomic dysfunction in fibromyalgia

    Science.gov (United States)

    Kim, Jieun; Loggia, Marco L.; Cahalan, Christine M.; Harris, Richard E.; Beissner, Florian; Garcia, Ronald G.; Kim, Hyungjun; Wasan, Ajay D.

    2015-01-01

    Objective Fibromyalgia (FM) is a chronic functional pain syndrome characterized by widespread pain, significant pain catastrophizing, sympathovagal dysfunction, and amplified temporal summation for evoked pain. While several studies have found altered resting brain connectivity in FM, studies have not specifically probed the somatosensory system, and its role in both somatic and non-somatic FM symptomatology. Our objective was to evaluate resting primary somatosensory cortex (S1) connectivity, and explore how sustained, evoked deep-tissue pain modulates this connectivity. Methods We acquired fMRI and electrocardiography data from FM patients and healthy controls (HC) during rest (REST) and sustained mechanical pressure pain (PAIN) over the lower leg. Functional connectivity associated with different S1 subregions was calculated, while S1leg (leg representation) connectivity was contrast between REST and PAIN, and correlated with clinically-relevant measures in FM. Results At REST, FM showed decreased connectivity between multiple ipsilateral and cross-hemispheric S1 subregions, which was correlated with clinical pain severity. PAIN, compared to REST, produced increased S1legconnectivity to bilateral anterior insula in FM, but not in HC. Moreover, in FM, sustained pain-altered S1legconnectivity to anterior insula was correlated with clinical/behavioral pain measures and autonomic responses. Conclusion Our study demonstrates that both somatic and non-somatic dysfunction in FM, including clinical pain, pain catastrophizing, autonomic dysfunction, and amplified temporal summation, are all closely linked with the degree to which evoked deep-tissue pain alters S1 connectivity to salience/affective pain processing regions. Additionally, diminished connectivity between S1 subregions at REST in FM may result from ongoing widespread clinical pain. PMID:25622796

  5. Collaborative Framework for Designing a Sustainability Science Programme: Lessons Learned at the National Autonomous University of Mexico

    Science.gov (United States)

    Charli-Joseph, Lakshmi; Escalante, Ana E.; Eakin, Hallie; Solares, Ma. José; Mazari-Hiriart, Marisa; Nation, Marcia; Gómez-Priego, Paola; Pérez-Tejada, César A. Domínguez; Bojórquez-Tapia, Luis A.

    2016-01-01

    Purpose: The authors describe the challenges and opportunities associated with developing an interdisciplinary sustainability programme in an emerging economy and illustrate how these are addressed through the approach taken for the development of the first postgraduate programme (MSc and PhD) in sustainability science at the National Autonomous…

  6. The role of actin and myosin during spermatogenesis.

    Science.gov (United States)

    Sun, Xiao; Kovacs, Tamas; Hu, Yan-Jun; Yang, Wan-Xi

    2011-08-01

    Spermatogenesis is a transitionary process in which the diploid spermatogonia transform into haploid mature spermatozoa. Actin and myosin have been implicated in various aspects during spermatogenesis. Actin is present in the form of monomer, oligomer and polymer within cells, the latter is called microfilament. There are five actin-containing structures during spermatogenesis, i.e., ectoplasmic specialization, acroplaxome, manchette in mammals, actin cones in Drosophila and acroframosome in Caridean shrimp. They are involved in the shaping and differentiating of spermatids. Along with spermatogenesis, the actin cytoskeletons show active remodeling in this process. Some actin binding or actin regulated proteins have been demonstrated to regulate dynamic changes of the actin-containing structures. Myosin, actin-dependent molecular motor, plays an important role during spermatogenesis, such as involving in acrosome biogenesis, vesicle transport, gene transcription and nuclear shaping. The actin cytoskeleton and actin binding/regulated proteins cooperate to facilitate spermatogenesis. In this review, we summarize the existing knowledge about the cytoskeletal structures consisting of actin, actin binding/regulated proteins and myosin during spermatogenesis.

  7. Intercellular adhesion molecules (ICAMs) and spermatogenesis

    Science.gov (United States)

    Xiao, Xiang; Mruk, Dolores D.; Cheng, C. Yan

    2013-01-01

    BACKGROUND During the seminiferous epithelial cycle, restructuring takes places at the Sertoli–Sertoli and Sertoli–germ cell interface to accommodate spermatogonia/spermatogonial stem cell renewal via mitosis, cell cycle progression and meiosis, spermiogenesis and spermiation since developing germ cells, in particular spermatids, move ‘up and down’ the seminiferous epithelium. Furthermore, preleptotene spermatocytes differentiated from type B spermatogonia residing at the basal compartment must traverse the blood–testis barrier (BTB) to enter the adluminal compartment to prepare for meiosis at Stage VIII of the epithelial cycle, a process also accompanied by the release of sperm at spermiation. These cellular events that take place at the opposite ends of the epithelium are co-ordinated by a functional axis designated the apical ectoplasmic specialization (ES)—BTB—basement membrane. However, the regulatory molecules that co-ordinate cellular events in this axis are not known. METHODS Literature was searched at http://www.pubmed.org and http://scholar.google.com to identify published findings regarding intercellular adhesion molecules (ICAMs) and the regulation of this axis. RESULTS Members of the ICAM family, namely ICAM-1 and ICAM-2, and the biologically active soluble ICAM-1 (sICAM-1) are the likely regulatory molecules that co-ordinate these events. sICAM-1 and ICAM-1 have antagonistic effects on the Sertoli cell tight junction-permeability barrier, involved in Sertoli cell BTB restructuring, whereas ICAM-2 is restricted to the apical ES, regulating spermatid adhesion during the epithelial cycle. Studies in other epithelia/endothelia on the role of the ICAM family in regulating cell movement are discussed and this information has been evaluated and integrated into studies of these proteins in the testis to create a hypothetical model, depicting how ICAMs regulate junction restructuring events during spermatogenesis. CONCLUSIONS ICAMs are crucial

  8. Intercellular adhesion molecules (ICAMs) and spermatogenesis.

    Science.gov (United States)

    Xiao, Xiang; Mruk, Dolores D; Cheng, C Yan

    2013-01-01

    During the seminiferous epithelial cycle, restructuring takes places at the Sertoli-Sertoli and Sertoli-germ cell interface to accommodate spermatogonia/spermatogonial stem cell renewal via mitosis, cell cycle progression and meiosis, spermiogenesis and spermiation since developing germ cells, in particular spermatids, move 'up and down' the seminiferous epithelium. Furthermore, preleptotene spermatocytes differentiated from type B spermatogonia residing at the basal compartment must traverse the blood-testis barrier (BTB) to enter the adluminal compartment to prepare for meiosis at Stage VIII of the epithelial cycle, a process also accompanied by the release of sperm at spermiation. These cellular events that take place at the opposite ends of the epithelium are co-ordinated by a functional axis designated the apical ectoplasmic specialization (ES)-BTB-basement membrane. However, the regulatory molecules that co-ordinate cellular events in this axis are not known. Literature was searched at http://www.pubmed.org and http://scholar.google.com to identify published findings regarding intercellular adhesion molecules (ICAMs) and the regulation of this axis. Members of the ICAM family, namely ICAM-1 and ICAM-2, and the biologically active soluble ICAM-1 (sICAM-1) are the likely regulatory molecules that co-ordinate these events. sICAM-1 and ICAM-1 have antagonistic effects on the Sertoli cell tight junction-permeability barrier, involved in Sertoli cell BTB restructuring, whereas ICAM-2 is restricted to the apical ES, regulating spermatid adhesion during the epithelial cycle. Studies in other epithelia/endothelia on the role of the ICAM family in regulating cell movement are discussed and this information has been evaluated and integrated into studies of these proteins in the testis to create a hypothetical model, depicting how ICAMs regulate junction restructuring events during spermatogenesis. ICAMs are crucial regulatory molecules of spermatogenesis. The proposed

  9. Autonomous Learning for English Acquisition in Blended e-Studies for Adults within the Context of Sustainable Development

    Science.gov (United States)

    Bojare, Inara

    2016-01-01

    Personality integration and self-realisation in the global economy and coevolution with multilingual cultural environment of sustainable learning society by means of technologies actualise the paradigm shift in science, and create the necessity for transdisciplinary research to resolve the problem of transformation of the system of values in the…

  10. Gene expression profiles of mouse spermatogenesis during recovery from irradiation

    DEFF Research Database (Denmark)

    Shah, Fozia J; Tanaka, Masami; Nielsen, John E

    2009-01-01

    BACKGROUND: Irradiation or chemotherapy that suspend normal spermatogenesis is commonly used to treat various cancers. Fortunately, spermatogenesis in many cases can be restored after such treatments but knowledge is limited about the re-initiation process. Earlier studies have described the cell......BACKGROUND: Irradiation or chemotherapy that suspend normal spermatogenesis is commonly used to treat various cancers. Fortunately, spermatogenesis in many cases can be restored after such treatments but knowledge is limited about the re-initiation process. Earlier studies have described...... the cellular changes that happen during recovery from irradiation by means of histology. We have earlier generated gene expression profiles during induction of spermatogenesis in mouse postnatal developing testes and found a correlation between profiles and the expressing cell types. The aim of the present...... work was to utilize the link between expression profile and cell types to follow the cellular changes that occur during post-irradiation recovery of spermatogenesis in order to describe recovery by means of gene expression. METHODS: Adult mouse testes were subjected to irradiation with 1 Gy...

  11. Effects of coal leachates on fish spermatogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, R.C

    1987-01-01

    The use of coal as a fuel source for power plants often involves the storage of coal on the plant site. Coal stored in this manner is subject to leaching by rain or groundwater, and the leachates may seep into surface waters. Coal leachates were examined for toxic effects on fish spermatogenesis. Nonbreeding mummichogs, Fundulus heteroclitus, were induced to enter breeding condition in the laboratory by exposure to 20{degree}C and a photoperiod of 16L:8D for 6 weeks. During this 6-weeks period, mummichogs were dosed in static exposure tanks with water extracts of coal (leachates). Chi-square analysis and Z test of proportions revealed a significant reduction in sperm production by fish exposed to some, but not all, coal leachates. This reduction was as much as 40-fold and occurred in a dose-dependent manner. Ordinarily, nonbreeding mummichogs collected immediately after the breeding season will not enter breeding condition in response to 16L:8D and 20{degree}C. Exposure of these photo-insensitive mummichogs to coal leachates under long photoperiod conditions for 8 weeks resulted in a significant increase in sperm production. Analysis of weekly sperm production by mummichogs from six field populations, either adjacent to or 2 miles upstream from coal-fired power plants, did not reveal significant differences during the breeding season. However, this sperm production was less than 1/10 that of a mummichog field population sampled concomitantly at the Chesapeake Bay Institute. The reduced sperm levels could not be related to reproductive toxin(s) contained in coal leachate. 13 refs., 1 figs., 3 tabs.

  12. Discovery of microRNAs during early spermatogenesis in chicken.

    Directory of Open Access Journals (Sweden)

    Lu Xu

    Full Text Available Spermatogenesis is a complex process that involves many elements. However, until now, little is known at the molecular level about spermatogenesis in poultry. Here we investigated microRNAs and their target genes that may be involved in germ cell development and spermatogonial in chicken. We used next-generation sequencing to analyze miRNA expression profiles in three types of germline cells: primordial germ cells (PGCs, spermatogonial stem cells (SSCs, and spermatogonia (Sp during early stage of spermatogenesis. After validated the candidate miRNAs and corresponding genes' expression in three types of cells, we found 15 miRNAs that were enriched 21 target genes that may be involved in spermatogenesis. Among the enriched miRNAs, miR-202-5p/3p were up-regulated in the Sp library and down-regulated in the PGCs library. Through RT-qPCR and Dual-Luciferase reporter assay, we confirmed that miR-202-5p bind to LIMK2 and involved in germ cell development. Collectively, we firstly discover the novel miRNAs, like miR-202-5p, and its related genes and pathways, expressed during the early spermatogonial stage in chicken, which will provide new clues for deciphering the molecular mechanism of the miRNAs regulating germline stem cell differentiation and spermatogenesis in chicken.

  13. Yangjing Capsule Ameliorates Spermatogenesis in Male Mice Exposed to Cyclophosphamide

    Directory of Open Access Journals (Sweden)

    Hongle Zhao

    2015-01-01

    Full Text Available Yangjing capsule (YC, a traditional Chinese compound herbal preparation, has been proven as an effective drug to improve spermatogenesis in clinical practice. However, its pharmacological mechanisms were not fully clarified. This study was designed to investigate the protective effects of YC on spermatogenesis in the mouse model of spermatogenesis dysfunction induced by cyclophosphamide (CP. The administration of YC significantly increased the epididymal index, sperm count, and sperm motility of model mice. Histopathological changes demonstrated that CP caused obvious structural damage to testis, which were reversed by the administration of YC. Results from TUNEL assay showed that treatment with YC dramatically decreased the apoptosis of spermatogenic cell induced by CP. Moreover, YC treatment could inhibit the mRNA and protein expression of Bax to Bcl-2 and also raised expression of AR at both mRNA and protein levels. These data suggest that YC might ameliorate spermatogenesis in male mice exposed to CP through inhibiting the apoptosis of spermatogenic cell and enhancing the actions of testosterone in spermatogenesis.

  14. [Identification of the meiotic events in grasshopper spermatogenesis].

    Science.gov (United States)

    Liu, Meng-Hao; Zhao, Kai-Qiang; Wang, Ya-Dong; Yang, Meng-Ping; Zhao, Ning-Ning; Yang, Da-Xiang

    2012-12-01

    The grasshoppers are ideal materials to study various meiotic stages of spermatogenesis due to their easy availability, fairly large chromosomes, and fewer numbers of chromosomes. It is easy to make temporary squash preparation of grasshopper testes; however, it is usually difficult for the beginners to differentiate between stages of meiosis. In view of this, we demonstrated the method of identification of meiotic stages by chromosome number and chromosome conformation, taking spermatogonial meiosis of Locusta migratoria manilensis as an example. We described briefly the mitosis of spermatogonia and the spermatogenesis of this species as well.

  15. Autonomic neuropathies

    Science.gov (United States)

    Low, P. A.

    1998-01-01

    A limited autonomic neuropathy may underlie some unusual clinical syndromes, including the postural tachycardia syndrome, pseudo-obstruction syndrome, heat intolerance, and perhaps chronic fatigue syndrome. Antibodies to autonomic structures are common in diabetes, but their specificity is unknown. The presence of autonomic failure worsens prognosis in the diabetic state. Some autonomic neuropathies are treatable. Familial amyloid polyneuropathy may respond to liver transplantation. There are anecdotal reports of acute panautonomic neuropathy responding to intravenous gamma globulin. Orthostatic hypotension may respond to erythropoietin or midodrine.

  16. Autonomous houses. Autonomous house

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, S. (Tokai University, Tokyo (Japan). Faculty of Engineering)

    1991-09-30

    Self-sufficiency type houses are outlined. On condition that people gain a certain amount of income in relation with the society, they self-suffice under the given environment, allowing themselves to accept a minimum of industrial products with small environmental load. Ordinary supply from outside of fossil energy and materials which depend on it is minimized. Types are classified into three: energy, energy materials and perfect self-sufficiency. A study project for environment symbiotic houses is progressing which is planned by the Ministry of Construction and Institute of Building Energy Conservation and is invested by a private company. Its target is making a house for halving an environmental load by CO{sub 2}, for the purpose of creating the environment symbiotic house which is nice to and in harmony with the global environment and human beings. As a part of the studies on energy-saving and resource conservation on houses, introduced is a plan of an autonomous house at Izu-Atagawa. The passive method and high thermal-insulation are used for air conditioning, and hot spring water for hot water supply. Electric power is generated by hydroelectric power generation using mountain streams and by solar cells. Staple food is purchased, while subsidiary food is sufficed. 17 refs., 4 figs., 1 tab.

  17. Cellular ontogeny of RBMY during human spermatogenesis and its ...

    Indian Academy of Sciences (India)

    2012-12-13

    Dec 13, 2012 ... [Abid S, Sagare-Patil V, Gokral J and Modi D 2013 Cellular ontogeny of RBMY during human spermatogenesis and its role in sperm motility. J. Biosci. 38 85-92] DOI 10.1007/s12038-012-9281-8. 1. Introduction. Genetic analysis of men with infertility and subfertility has led to identification of genes that are ...

  18. Inhibin B as a serum marker of spermatogenesis

    DEFF Research Database (Denmark)

    Jensen, T K; Andersson, A M; Hjollund, N H

    1997-01-01

    Recent studies have focused on reproductive health of men in the general population. However, semen samples are difficult to obtain within sampling frames that allow comparisons. Blood samples are easier to obtain than ejaculates. Therefore, serum biomarkers of spermatogenesis are of major intere...

  19. The role of the tumor suppressor p53 in spermatogenesis

    NARCIS (Netherlands)

    Beumer, T. L.; Roepers-Gajadien, H. L.; Gademan, I. S.; van Buul, P. P.; Gil-Gomez, G.; Rutgers, D. H.; de rooij, D. G.

    1998-01-01

    The p53 protein appeared to be involved in both spermatogonial cell proliferation and radiation response. During normal spermatogenesis in the mouse, spermatogonia do not express p53, as analyzed by immunohistochemistry. However, after a dose of 4 Gy of X-rays, a distinct p53 staining was present in

  20. Dynamic reorganization of open chromatin underlies diverse transcriptomes during spermatogenesis

    Science.gov (United States)

    Maezawa, So; Yukawa, Masashi; Alavattam, Kris G; Barski, Artem

    2018-01-01

    Abstract During spermatogenesis, germ cells undergo massive cellular reconstruction and dynamic chromatin remodeling to facilitate highly diverse transcriptomes, which are required for the production of functional sperm. However, it remains unknown how germline chromatin is organized to promote the dynamic, complex transcriptomes of spermatogenesis. Here, using ATAC-seq, we establish the varied landscape of open chromatin during spermatogenesis. We identify the reorganization of accessible chromatin in intergenic and intronic regions during the mitosis-to-meiosis transition. During the transition, mitotic-type open chromatin is closed while the de novo formation of meiotic-type open chromatin takes place. Contrastingly, differentiation processes such as spermatogonial differentiation and the meiosis-to-postmeiosis transition involve chromatin closure without the de novo formation of accessible chromatin. In spermiogenesis, the germline-specific Polycomb protein SCML2 promotes the closure of open chromatin at autosomes for gene suppression. Paradoxically, we identify the massive de novo formation of accessible chromatin when the sex chromosomes undergo meiotic sex chromosome inactivation, and this is also mediated by SCML2. These results reveal meiotic sex chromosome inactivation as an active process for chromatin organization. Together, our results unravel the genome-wide, dynamic reorganization of open chromatin and reveal mechanisms that underlie diverse transcriptomes during spermatogenesis. PMID:29126117

  1. Protamines and spermatogenesis in Drosophila and Homo sapiens : A comparative analysis.

    Science.gov (United States)

    Kanippayoor, Rachelle L; Alpern, Joshua H M; Moehring, Amanda J

    2013-04-01

    The production of mature and motile sperm is a detailed process that utilizes many molecular players to ensure the faithful execution of spermatogenesis. In most species that have been examined, spermatogenesis begins with a single cell that undergoes dramatic transformation, culminating with the hypercompaction of DNA into the sperm head by replacing histones with protamines. Precise execution of the stages of spermatogenesis results in the production of motile sperm. While comparative analyses have been used to identify similarities and differences in spermatogenesis between species, the focus has primarily been on vertebrate spermatogenesis, particularly mammals. To understand the evolutionary basis of spermatogenetic variation, however, a more comprehensive comparison is needed. In this review, we examine spermatogenesis and the final packaging of DNA into the sperm head in the insect Drosophila melanogaster and compare it to spermatogenesis in Homo sapiens.

  2. Sustainability

    OpenAIRE

    Harris, Nora; Shealy, Tripp; Klotz, Leidy

    2016-01-01

    Across fields, more sustainable and resilient outcomes are being realized through a whole systems design perspective, which guides decision-makers to consider the entire system affected including interdependent physical and social networks. Although infrastructure is extremely interdependent, consisting of diverse stakeholders and networks, the infrastructure design and construction process is often fragmented. This fragmentation can result in unnecessary tradeoffs, leading to poor outcomes f...

  3. Autonomous search

    CERN Document Server

    Hamadi, Youssef; Saubion, Frédéric

    2012-01-01

    Autonomous combinatorial search (AS) represents a new field in combinatorial problem solving. Its major standpoint and originality is that it considers that problem solvers must be capable of self-improvement operations. This is the first book dedicated to AS.

  4. Ultrastructure of spermatogenesis in the testis of Paragonimus heterotremus.

    Science.gov (United States)

    Uabundit, Nongnut; Kanla, Pipatphong; Puthiwat, Phongphithak; Arunyanart, Channarong; Chaiciwamongkol, Kowit; Maleewong, Wanchai; Intapan, Pewpan M; Iamsaard, Sitthichai; Hipkaeo, Wiphawi

    2013-12-01

    Lung fluke, Paragonimus heterotremus, is a flatworm causing pulmonary paragonimiasis in cats, dogs, and humans in Southeast Asia. We examined the ultrastructure of the testis of adult P. heterotremus with special attention to spermatogenesis and spermiogenesis using scanning and transmission electron microscopy. The full sequence of spermatogenesis and spermiogenesis, from the capsular basal lamina to the luminal surface, was demonstrated. The sequence comprises spermatogonia, spermatocytes with obvious nuclear synaptonemal complexes, spermatids, and eventual spermatozoa. Moreover, full steps of spermatid differentiation were shown which consisted of 1) early stage, 2) differentiation stage representing the flagella, intercentriolar body, basal body, striated rootlets, and electron dense nucleus of thread-like lamellar configuration, and 3) growing spermatid flagella. Detailed ultrastructure of 2 different types of spermatozoa was also shown in this study.

  5. Ultrastructure of Spermatogenesis of the Paradise Fish, Macropodus opercularis

    Directory of Open Access Journals (Sweden)

    Tsung-Han Lee

    2006-09-01

    Full Text Available The intricate process of spermatogenesis in the paradise fish, Macropodus opercularis, was studied. In this species, the unrestricted or lobular type testes lining the caudal side of the body cavity are translucent and slender. Spermatogonia occur along the length of the tubules and the development of sperm takes place within cysts formed by Sertoli cells. Spermiogenesis involves preparatory morphological events followed by conspicuous modifications such as the movement of the centrioles, completion of the nuclear condensation, reduction of the cytoplasm, and the final differentiation of the flagellar complex. Mature spermatozoon has an oval nucleus, condensed chromatin, and typical 9 + 2 flagellar axoneme but lack acrosome. The role of the material in the nucleus and the cytoplasm as it reaches the Sertoli cell in the control of spermatogenesis is discussed.

  6. Testicular Characteristics and the Block to Spermatogenesis in Mature Hinny

    Directory of Open Access Journals (Sweden)

    Hongmei Han

    2016-06-01

    Full Text Available Most hinnies (female donkey×male horse and mules (female horse×male donkey are sterile with few reports of equine fertile hybrids. The main cause of this sterility is thought to be a meiotic block to spermatogenesis and oogenesis. This study compared the developmental features of the testes and a histological analyses of spermatogenesis in a male hinny with those of a normal, fertile stallion and Jack donkey. Hinny testes showed a thicker tunica albuginea, fewer blood vessels and more connective tissue in the testis parenchyma than those of the stallion and Jack donkey. Although the mean number of seminiferous tubules was significantly higher in stallion and hinny than Jack donkey (p<0.01, the mean proportion of seminiferous tubules was lower in the hinny (p<0.01 which resulted in a smaller diameter of seminiferous tubules. The mean number of spermatogonia and spermatocytes per unit area were significantly lower in hinny testis (p<0.01 and no spermatids or mature spermatozoa cells were found during immunofluorescent analyses. These results indicated that defects in seminiferous tubule development and structure occur in the testis of hinnies. Furthermore, most spermatogonia and spermatocytes cease development in synapsis during mid-meiosis of spermatocytes, which results in a block to spermatogenesis that prevents the formation of spermatids and matured spermatozoa during meiosis in male hinnies.

  7. Sperm competition-induced plasticity in the speed of spermatogenesis.

    Science.gov (United States)

    Giannakara, Athina; Schärer, Lukas; Ramm, Steven A

    2016-03-08

    Sperm competition between rival ejaculates over the fertilization of ova typically selects for the production of large numbers of sperm. An obvious way to increase sperm production is to increase testis size, and most empirical work has focussed on this parameter. Adaptive plasticity in sperm production rate could also arise due to variation in the speed with which each spermatozoon is produced, but whether animals can respond to relevant environmental conditions by modulating the kinetics of spermatogenesis in this way has not been experimentally investigated. Here we demonstrate that the simultaneously hermaphroditic flatworm Macrostomum lignano exhibits substantial plasticity in the speed of spermatogenesis, depending on the social context: worms raised under higher levels of sperm competition produce sperm faster. Our findings overturn the prevailing view that the speed of spermatogenesis is a static property of a genotype, and demonstrate the profound impact that social environmental conditions can exert upon a key developmental process. We thus identify, to our knowledge, a novel mechanism through which sperm production rate is maximised under sperm competition.

  8. The treatment of autonomic dysfunction in tetanus

    Directory of Open Access Journals (Sweden)

    T van den Heever

    2017-07-01

    Full Text Available We report a case of generalised tetanus in a 50-year-old female patient after sustaining a wound to her right lower leg. She developed autonomic dysfunction, which included labile hypertension alternating with hypotension and sweating. The autonomic dysfunction was treated successfully with a combination of morphine sulphate infusion, magnesium sulphate, and clonidine. She also received adrenaline and phenylephrine infusions as needed for hypotension. We then discuss the pathophysiology, clinical features and treatment options of autonomic dysfunction.

  9. Connexin 43 expression in human and mouse testes with impaired spermatogenesis

    Directory of Open Access Journals (Sweden)

    M Kotula-Balak

    2009-08-01

    Full Text Available Connexin 43 (Cx43 belongs to a family of proteins that form gap junction channels. The aim of this study was to examine the expression of Cx43 in the testis of a patient with Klinefelter’s syndrome and of mice with the mosaic mutation and a partial deletion in the long arm of the Y chromosome. These genetic disorders are characterized by the presence of numerous degenerated seminiferous tubules and impaired spermatogenesis. In mouse testes, the expression and presence of Cx43 were detected by means of immunohistochemistry and Western blot analysis, respectively. In testes of Klinefelter’s patient only immunoexpression of Cx43 was detected. Regardless of the species Cx43 protein was ubiquitously distributed in testes of reproductively normal males, whereas in those with testicular disorders either a weak intensity of staining or no staining within the seminiferous tubules was observed. Moderate to strong or very strong staining was confined to the interstitial tissue. In an immunoblot analysis of testicular homogenates Cx43 appeared as one major band of approximately 43 kDa. Our study adds three more examples of pathological gonads in which the absence or apparent decrease of Cx43 expression within the seminiferous tubules was found. A positive correlation between severe spermatogenic impairment and loss of Cx43 immunoreactivity observed in this study supports previous data that gap junctions play a crucial role in spermatogenesis. Strong Cx43 expression detected mostly in the interstitial tissue of the Klinefelter’s patient may presumably be of importance in sustaining Leydig cell metabolic activity. However, the role of gap junction communication in the control of Leydig cell function seems to be more complex than originally thought.

  10. Subcellular distribution of calcium during spermatogenesis of zebrafish, Danio rerio.

    Science.gov (United States)

    Golpour, Amin; Pšenička, Martin; Niksirat, Hamid

    2017-08-01

    Calcium plays a variety of vital regulatory functions in many physiological and biochemical events in the cell. The aim of this study was to describe the ultrastructural distribution of calcium during different developmental stages of spermatogenesis in a model organism, the zebrafish (Danio rerio), using a combined oxalate-pyroantimonate technique. Samples were treated by potassium oxalate and potassium pyroantimonate during two fixation stages and examined using transmission electron microscopy to detect electron dense intracellular calcium. The subcellular distribution of intracellular calcium was characterized in spermatogonium, spermatocyte, spermatid, and spermatozoon stages. The area which is covered by intracellular calcium in different stages was quantified and compared using software. Isolated calcium deposits were mainly detectable in the cytoplasm and the nucleus of the spermatogonium and spermatocyte. In the spermatid, calcium was partially localized in the cytoplasm as isolated deposits. However, most calcium was transformed from isolated deposits into an unbound pool (free calcium) within the nucleus of the spermatid and the spermatozoon. Interestingly, in the spermatozoon, calcium was mainly localized in a form of an unbound pool which was detectable as an electron-dense mass within the nucleus. Also, sporadic calcium deposits were scattered in the midpiece and flagellum. The proportional area which was covered by intracellular calcium increased significantly from early to late stages of spermatogenesis. The extent of the area which was covered by intracellular calcium in the spermatozoon was the highest compared to earlier stages. Calcium deposits were also observed in the somatic cells (Sertoli, myoid, Leydig) of zebrafish testis. The notable changes in the distribution of intracellular calcium of germ cells during different developmental stages of zebrafish spermatogenesis suggest its different homeostasis and physiological functions during the

  11. In vitro spermatogenesis using an organ culture technique.

    Science.gov (United States)

    Yokonishi, Tetsuhiro; Sato, Takuya; Katagiri, Kumiko; Ogawa, Takehiko

    2013-01-01

    Research on in vitro spermatogenesis has a long history and remained to be an unaccomplished task until very recently. In 2010, we succeeded in producing murine sperm from primitive spermatogonia using an organ culture method. The fertility of the sperm or haploid spermatids was demonstrated by microinsemination. This organ culture technique uses the classical air-liquid interphase method and is based on conditions extensively examined by Steinbergers in 1960s. Among adaptations in the new culture system, application of serum-free media was the most important. The system is very simple and easy to follow.

  12. The postnatal progeny development of males whose sexual cells were irradiated during different stages of spermatogenesis

    International Nuclear Information System (INIS)

    Lepekhin, N.P.; Palyga, G.F.

    1995-01-01

    Distinct genetic radiosensitivity if germinal cells of males irradiated during different stages of spermatogenesis with doses of 0.25-5.0 Gy leads to reduction in vital newborn rats number in the first generation progeny and to elevated postnatal mortality rate. These postnatal ontogeny disorders depend on the irradiation dose and spermatogenesis stage for a moment irradiation. 11 refs.; 4 tabs

  13. Effect of acetylsalicylic acid on spermatogenesis in adult albino mice

    International Nuclear Information System (INIS)

    Ameer, M.K.; Tahrir, M.

    2015-01-01

    Spermatogenesis in male albino mice. Study Design: Laboratory based randomized controlled trial. Place and Duration of Study: Department of Anatomy University of Health Sciences, Lahore from Apr, 2012 to Dec, 2012. Material and Methods: Thirty nine male albino mice, 6-8 weeks old weighing 30 - 5 gm, were used; these were randomly divided into three groups having thirteen mice in each using random numbers table. Group A served as a control and was given distilled water orally via oral gavage 10 ml per kg for 30 days. Group B was given acetylsalicylic acid 100 mg/kg dissolved in 10 ml distilled orally for a period of 30 days. Group C was given acetylsalicylic acid 25 mg/kg dissolved in 2.5 ml distilled orally for a period of 30 days. Animals were sacrificed 24 hours after the last dose and the testes were removed, fixed in Bouin's fixative for 48 hours. Five microns thick sections of processed tissue were stained with H and E and PAS for calculation of Johnsen score and diameter of seminiferous tubules. Serum testosterone level was measured by testosterone enzyme immunoassay test kits. Results: Microscopic examination demonstrated that ASA treatment lead to statistically significant increase in the mean Johnsen score and mean diameter of seminiferous tubules. Conclusion: It was concluded from the current study that ASA treatment enhances spermatogenesis. (author)

  14. Ultrastructural study of spermatogenesis in Phoronopsis harmeri (Lophophorata, Phoronida)

    Science.gov (United States)

    Reunov, Arkadiy; Klepal, Waltraud

    2004-02-01

    The process of sperm development in Phoronopsis harmeri was studied by electron microscopy. Developing spermatogenical cells are aggregated around the capillaries of the haemal plexus. The spermatogonia, which are situated around the capillary walls of the caeca, are remarkable for the presence of germ-line vesicles and contain their centrioles near the cell membrane. The spermatocytes and spermatids are flagellated cells arranged in clusters. During spermiogenesis the basal body/flagellum complex migrates to the apical pole of the spermatid. The acrosome-like structure arises from material produced by the Golgi complex. It lacks a surrounding membrane and has a fibrillar content. The nucleus elongates and the condensation of chromatin is caused by an activation of 'initiation centres'. The late spermatid and the spermatozoon appear as two-armed 'V'-shaped cells in which one arm contains the nucleus and posteriorly located mitochondria, and the other one is the axoneme. Spermatogenesis of P. harmeri is an interesting example of gamete differentiation where advanced sperm structure is combined with a plesiomorphic pattern of sperm development characterized as 'flagellate spermatogenesis'.

  15. Nucleolar persistence during spermatogenesis of the genus Rhodnius (Hemiptera, Triatominae).

    Science.gov (United States)

    Alevi, Kaio Cesar Chaboli; da Costa Castro, Nayara Fernanda; Lima, Anna Claudia Campaner; Ravazi, Amanda; Morielle-Souza, Alessandra; de Oliveira, Jader; da Rosa, João Aristeu; de Azeredo Oliveira, Maria Tercília Vilela

    2014-08-01

    The Triatominae subfamily is comprised of 18 genera and six tribes. The tribe Rhodniini is comprised of two genera (Rhodnius and Psammolestes). Nucleolar persistence is defined by the presence of the nucleolus or nucleolar corpuscles during the meiotic metaphase. To date, this phenomenon has been described for 13 species of triatomine that are included in the genera Triatoma, Rhodnius, and Panstrongylus. Thus, because the phenomenon of nucleolar persistence has been described in only two species of the genus Rhodnius, we have analyzed the nucleolar behavior during spermatogenesis of eight species of the genus Rhodnius (R. colombiensis, R. montenegrensis, R. nasutus, R. neglectus, R. neivai, R. pictipes, R. prolixus, and R. robustus), with a focus on nucleolar persistence. By means of cytogenetic analysis with silver ions, nucleolar behavior during spermatogenesis is described in the eight species of Rhodnius analyzed. In all of them nucleolar behavior was similar and the phenomenon of nucleolar persistence was often observed. Therefore, we confirm nucleolar persistence as a peculiarity of the genus Rhodnius. However, it is emphasized that new cytogenetic analysis should be performed in the Triatominae subfamily, more specifically among the 15 genera that do not exhibit the nucleolar behavior described, in order to assess whether this phenomenon is truly a synapomorphy of these hematophagous insects. © 2014 International Federation for Cell Biology.

  16. [The role of Gilgamesh protein kinase in Drosophila melanogaster spermatogenesis].

    Science.gov (United States)

    Nerusheva, O O; Dorogova, N V; Gubanova, N V; Omel'ianchuk, L V

    2008-09-01

    The cellular function of the gilgamesh mutation (89B9-12) of casein kinase gene in Drosophila spermatogenesis was studied. It was demonstrated that the sterility resulting from this mutation is connected with the abnormalities in spermatid individualization. A phylogenetic study of the protein sequences of casein kinases 1 from various organisms was conducted. The Gilgamesh protein was shown to be phylogenetically closer to the cytoplasmic casein kinase family, represented by the YCK3, YCK2, and YCK1 proteins of Saccharomyces cerevisiae and animal gamma-casein kinases. It is known that these yeast casein kinases are involved in vesicular trafficking, which, in turn, is related in its genetic control to the cell membrane remodeling during spermatid individualization. Thus, the data of phylogenetic analysis fit well the results obtained by studying the mutation phenotype.

  17. [Influence of TORCH-infections on the spermatogenesis of men].

    Science.gov (United States)

    Bukia, T Sh; Shanidze, L Sh; Maisuradze, K G

    2010-01-01

    The purpose of the given study was to reveal causal relations between infection of the urino-genital tract by intracellular parasites, the so-called TORCH-infections, and the decrease of spermatogenesis. For observation 182 men of reproductive age (from 22 to 38 years) with oligozoospermia and aspermia, without any complaints or clinical symptoms indicating existence of infections of urino-genital tracts, were selected. Out of those, 131 revealed oligozoospermia, i.e. the quantity of spermatozoons was no higher than 20 mln in 1 ml of ejaculate, and 51 revealed - aspermia. For examination of some TORCH infections, medical doctors in charge directed 44 oligozoospermia patients and 15 aspermia patients, who respectively constituted group I and group II. Examinations were carried out for Chlamydia trachomatis--(Ch.t), Herpes simplex virus--(HSV), Ureaplasma urealiticum--(U.u.), Cytomegalovirus--(CMV), and Mycoplasma hominis--(M.h.). In the group with oligozoospermia, cases of infections by Chlamydias (41.5%) and Herpes virus (51.3%) were frequent, but Ureaplasma (56,5%) was more frequent than any infections. Cytomegalovirus occurred in the least number of cases. Making any conclusions on the frequency of infections by M.h. is difficult due to the low number of examinations. Similar picture was observed in Group II as well. Following successful treatment of infections in Group I, 8 patients with Ch.t. and 8 patients with U.u. showed an improved spermogram after several months. Treatment of other infections did not yield tangible results. In Group II spermatogenesis remained without any changes.

  18. The effect of aminopterin-induced folic acid deficiency on spermatogenesis.

    Science.gov (United States)

    Mathur, U; Datta, S L; Mathur, B B

    1977-12-01

    Folic acid deficiency was produced by injecting aminopterin into adult male albino rats, resulting in inhibition of spermatogenesis. Bone marrow smears were studied to serve as an index of folic acid deficiency; however, changes in spermatogenesis were noticed earlier than the bone marrow changes. Meiotic division was affected more than mitotic division. The nuclei of spermatogenic cells showed degenerative changes. Chromosomal abnormalities, chiefly sticky chromosomes, were noticed in squashed preparations of seminiferous tubules.

  19. DNA fragmentation in spermatozoa and its relationship with impaired spermatogenesis

    Directory of Open Access Journals (Sweden)

    S. A. Rudneva

    2014-01-01

    Full Text Available Sperm cells DNA fragmentation is one of the factors of male sub-/infertility discovered recently. At present, pathophysiological mechanisms that cause DNA fragmentation have not been studied completely. It is suggested that they may be caused with defects of chromatin remodeling, apoptosis, and oxidative stress. Spermiological examination was performed in 461 infertile men. With 23 % of the patients examined, the frequency of sperm cells DNA fragmentation comprises over 15 %, with that, 18 % of the patients demonstrated its range from 15.1 to 30 %, and with 5 % of patients, it exceeded 30 %. We found that the amount of sperm cells with fragmented DNA with severe forms of pathozoospermia is higher that with less manifested disturbances of spermatogenesis. Negative dynamics was revealed regarding the change in sperm concentration in men that have increased frequency of DNA fragmentation. Obtained results confirm the suggestion of the correlation between some semen parameters (concentration, motility, and morphology and sperm DNA fragmentation. Thus, one can state that the DNA fragmentation parameter of sperm cells has a certain diagnostic and forecasting value for married couples with reproduction disorders.

  20. Spermatogenesis in Nesotriatoma bruneri (Usinger 1944) (Hemiptera, Triatominae).

    Science.gov (United States)

    Reis, Y V; Alevi, K C C; Moreira, F F F; Azeredo-Oliveira, M T V

    2016-08-19

    The Nesotriatoma genus consists of the species N. flavida N. bruneri and N. obscura, forming the Flavida complex. Variation in the size and morphological differences intraspecific of N. flavida led to the description of N. bruneri. Two years later, the same author proposed the synonymization of N. bruneri with N. flavida. Only in 1981 the specific status N. bruneri was recovered by means of morphological analysis of the genitalia. However, recently by genetic analysis, it was suggested that N. bruneri and N. flavida should be again synonymized. As Chagas disease has no cure, the main way to minimize the incidence of this disease is by vector control. Thus, grouping biological data from these hematophagous insects can assist in the development of vector control programs and mainly assist in taxonomic issues of synonymization. Thus, this paper describes spermatogenesis of N. bruneri. Three adult N. bruneri males were cytogenetically analyzed. The meiotic behavior observed for N. bruneri was very similar to that observed for the triatomine species with 23 chromosomes: during prophase, chromatin compaction was observed, the chromocenter composition was characterized (X 1 , X 2 and Y), and the species karyotype was confirmed as 2n = 23 (20A + X 1 X 2 Y), as it was observed for N. flavida. Moreover, it was possible to observe anaphase and telophase. Thus, this study describes reproductive aspects of N. bruneri in order to contribute to the biological knowledge of these insects of epidemiological importance. Furthermore, this corroborates the synonymization of N. bruneri with N. flavida.

  1. Polysialylation of NCAM correlates with onset and termination of seasonal spermatogenesis in roe deer.

    Science.gov (United States)

    Hänsch, Manka; Simon, Peter; Schön, Jennifer; Kaese, Miriam; Braun, Beate C; Jewgenow, Katarina; Göritz, Franz; Küpper, Julia; Ahmadvand, Negah; Geyer, Rudolf; Middendorff, Ralf; Müller, Karin; Galuska, Sebastian P

    2014-06-01

    Roe deer (Capreolus capreolus) are seasonal breeders and cyclic structural changes of roe bucks' testis come along with a totally arrested (winter) and a highly activated spermatogenesis (summer). For this reason, roe buck represents an interesting model to study general mechanisms of initiation and termination of spermatogenesis. We investigated if polysialic acid (polySia)-a linear homopolymer of α2,8-linked sialic acids, which could act as a negative regulator of cell-cell adhesion-might be involved in the activation and/or inactivation of spermatogenesis. To address this point, testis samples of adult male roe deer were collected at different time point of the year. Intriguingly, we observed that polySia attached to the neural cell adhesion molecule was enhanced during the onset of spermatogenesis in April. In addition, polySia was highly expressed in December. Predominantly, polySia was detectable between Sertoli cells and spermatogonia in the basal regions of testicular tubules and in the adluminal part of Sertoli cells. Interestingly, similar polySia distributions were observed during early testis development of other mammalians when gonocytes (pre-spermatogonia) and Sertoli cells represent the only cell populations in tubuli seminiferi. Thus, polySia is expressed during key steps of the "on/off mechanisms" of spermatogenesis and might represent one mediator of the interaction and communication between Sertoli cells and germ cell precursors.

  2. High butter-fat diet and bisphenol A additively impair male rat spermatogenesis.

    Science.gov (United States)

    Tarapore, Pheruza; Hennessy, Max; Song, Dan; Ying, Jun; Ouyang, Bin; Govindarajah, Vinothini; Leung, Yuet-Kin; Ho, Shuk-Mei

    2017-03-01

    Exposure to xenoestrogens is a probable cause of male infertility in humans. Consumption of high-fat diets and exposure to bisphenol A (BPA) is pervasive in America. Here, we test the hypothesis that gestational exposure to high dietary fats and/or BPA disrupt spermatogenesis in adulthood. Sprague-Dawley rats were fed diets containing 10kcal% butter fat (AIN), 39kcal% butter fat (HFB), or 39kcal% olive oil (HFO), with or without BPA (25μg/kg body weight/day) during pregnancy. One group of male offspring received testosterone (T)- and estradiol-17β (E2)-filled implants or sham-implants from postnatal day (PND)70-210. Another group was naturally aged to 18 months. We found that adult males with gestational exposure to BPA, HFB, or HFB+BPA, in both the aged group and the T+E2-implanted group, exhibited impairment of spermatogenesis. In contrast, gestational exposure to HFO or HFO+BPA did not affect spermatogenesis. Sham-implanted, gestational exposed groups also had normal spermatogenesis. Loss of ERα expression in round spermatids and premature expression of protamine-1 in diplotene spermatocytes were features associated with impaired spermatogenesis. Compared with the single-treatment groups, the HFB+BPA group experienced more severe effects, including atrophy. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Deleterious effects of obesity upon the hormonal and molecular mechanisms controlling spermatogenesis and male fertility.

    Science.gov (United States)

    Davidson, Lien M; Millar, Kate; Jones, Celine; Fatum, Muhammad; Coward, Kevin

    2015-09-01

    Worldwide obesity rates have nearly doubled since 1980 and currently over 10% of the population is obese. In 2008, over 1.4 billion adults aged 20 years and older had a body mass index or BMI above a healthy weight and of these, over 200 million men and nearly 300 million women were obese. While obesity can have many ramifications upon adult life, one growing area of concern is that of reproductive capacity. Obesity affects male infertility by influencing the hypothalamic-pituitary-gonadal axis, thus causing detrimental effects upon spermatogenesis and subsequent fertility. In particular, evidence indicates that excess adipose tissue can alter the relative ratio of testosterone and oestrogen. Additional effects involve the homeostatic disruption of insulin, sex-hormone-binding-globulin, leptin and inhibin B, leading to diminished testosterone production and impairment to spermatogenesis. Aberrant spermatogenesis arising from obesity is associated with downstream changes in key semen parameters, defective sperm capacitation and binding, and deleterious effects on sperm chromatin structure. More recent investigations into trans-generational epigenetic inheritance further suggest that molecular changes in sperm that arise from obesity-related impaired spermatogenesis, such as modified sperm RNA levels, DNA methylation, protamination and histone acetylation, can impact upon the development of offspring. Here, we summarise our current understanding of how obesity exerts influence over spermatogenesis and subsequent fertility status, and make recommendations for future investigative research.

  4. The treatment of autonomic dysfunction in tetanus | Maryke Spruyt ...

    African Journals Online (AJOL)

    We report a case of generalised tetanus in a 50-year-old female patient after sustaining a wound to her right lower leg. She developed autonomic dysfunction, which included labile hypertension alternating with hypotension and sweating. The autonomic dysfunction was treated successfully with a combination of morphine ...

  5. Autonomic Nervous System Disorders

    Science.gov (United States)

    Your autonomic nervous system is the part of your nervous system that controls involuntary actions, such as the beating of your heart ... breathing and swallowing Erectile dysfunction in men Autonomic nervous system disorders can occur alone or as the result ...

  6. Autonomous Industrial Mobile Manipulation (AIMM)

    DEFF Research Database (Denmark)

    Hvilshøj, Mads; Bøgh, Simon; Nielsen, Oluf Skov

    2012-01-01

    Purpose - The purpose of this paper is to provide a review of the interdisciplinary research field Autonomous Industrial Mobile Manipulation (AIMM), with an emphasis on physical implementations and applications. Design/methodology/approach - Following an introduction to AIMM, this paper investiga......Purpose - The purpose of this paper is to provide a review of the interdisciplinary research field Autonomous Industrial Mobile Manipulation (AIMM), with an emphasis on physical implementations and applications. Design/methodology/approach - Following an introduction to AIMM, this paper......; sustainability, configuration, adaptation, autonomy, positioning, manipulation and grasping, robot-robot interaction, human-robot interaction, process quality, dependability, and physical properties. Findings - The concise yet comprehensive review provides both researchers (academia) and practitioners (industry...... Manipulation (AIMM)....

  7. Spermatozoa and spermatogenesis in the northern quahaug Mercenaria mercenaria (Mollusca, Bivalvia)

    Science.gov (United States)

    Ying, Xue-Ping; Yang, Wan-Xi; Dahms, Hans-U.; Lin, Zhihua; Chai, Xueliang

    2008-12-01

    We studied the ultrastructure of spermatogenesis and spermatozoa in the northern quahaug, the clam Mercenaria mercenaria. Spermatogenetic cells gradually elongate. Mitochondria gradually fuse and increase in size and electron density. During spermatid differentiation, proacrosomal vesicles migrate towards the presumptive anterior pole of the nucleus and eventually form the acrosome. The spermatozoon of M. mercenaria is of a primitive type. It is composed of head, mid-piece, and tail. The acrosome shows a subacrosomal space with a short conical contour. The slightly curved nucleus of the spermatozoon contains fine-grained dense chromatin. The middle piece consists of a centriolar complex which is surrounded by four mitochondria. The flagellum has a standard “9 + 2” microtubular structure. The ultrastructure of spermatozoa and spermatogenesis of M. mercenaria shares a number of features with other species of the family Veneridae. M. mercenaria may be a suitable model species for further investigations into the mechanisms of spermatogenesis in the Bivalvia.

  8. Ultrastructural investigation of spermatogenesis in the nemerine worm Procephalothrix sp. (Palaeonemertini, Anopla)

    Science.gov (United States)

    Reunov, A. A.; Klepal, W.

    1997-08-01

    Spermatogenesis and sperm structure of the nemertine worm Procephalothrix sp. were studied by transmission electron microscopy. It is shown that a flagellum and proacrosomal vesicles are common in spermatogonia and spermatocytes as in spermatogenesis of a number of marine invertebrates with external fertilization. Originally, the animals were collected as Procephalothrix spiralis but they were found to have a type of spermatozoon different from that of P. spiralis as described by Turbeville & Ruppert (1985). The re-identification of the material collected in the Japan Sea has shown that the features are characteristic, of P. spiralis (Coe, 1930). This finding suggests that P. spiralis shows variations in different parts of the world.

  9. Recovery of spermatogenesis following testosterone replacement therapy or anabolic-androgenic steroid use.

    Science.gov (United States)

    McBride, J Abram; Coward, Robert M

    2016-01-01

    The use of testosterone replacement therapy (TRT) for hypogonadism continues to rise, particularly in younger men who may wish to remain fertile. Concurrently, awareness of a more pervasive use of anabolic-androgenic steroids (AAS) within the general population has been appreciated. Both TRT and AAS can suppress the hypothalamic-pituitary-gonadal (HPG) axis resulting in diminution of spermatogenesis. Therefore, it is important that clinicians recognize previous TRT or AAS use in patients presenting for infertility treatment. Cessation of TRT or AAS use may result in spontaneous recovery of normal spermatogenesis in a reasonable number of patients if allowed sufficient time for recovery. However, some patients may not recover normal spermatogenesis or tolerate waiting for spontaneous recovery. In such cases, clinicians must be aware of the pathophysiologic derangements of the HPG axis related to TRT or AAS use and the pharmacologic agents available to reverse them. The available agents include injectable gonadotropins, selective estrogen receptor modulators, and aromatase inhibitors, but their off-label use is poorly described in the literature, potentially creating a knowledge gap for the clinician. Reviewing their use clinically for the treatment of hypogonadotropic hypogonadism and other HPG axis abnormalities can familiarize the clinician with the manner in which they can be used to recover spermatogenesis after TRT or AAS use.

  10. Rapid male-specific regulatory divergence and down regulation of spermatogenesis genes in Drosophila species hybrids.

    Directory of Open Access Journals (Sweden)

    Jennifer Ferguson

    Full Text Available In most crosses between closely related species of Drosophila, the male hybrids are sterile and show postmeiotic abnormalities. A series of gene expression studies using genomic approaches have found significant down regulation of postmeiotic spermatogenesis genes in sterile male hybrids. These results have led some to suggest a direct relationship between down regulation in gene expression and hybrid sterility. An alternative explanation to a cause-and-effect relationship between misregulation of gene expression and male sterility is rapid divergence of male sex regulatory elements leading to incompatible interactions in an interspecies hybrid genome. To test the effect of regulatory divergence in spermatogenesis gene expression, we isolated 35 fertile D. simulans strains with D. mauritiana introgressions in either the X, second or third chromosome. We analyzed gene expression in these fertile hybrid strains for a subset of spermatogenesis genes previously reported as significantly under expressed in sterile hybrids relative to D. simulans. We found that fertile autosomal introgressions can cause levels of gene down regulation similar to that of sterile hybrids. We also found that X chromosome heterospecific introgressions cause significantly less gene down regulation than autosomal introgressions. Our results provide evidence that rapid male sex gene regulatory divergence can explain misexpression of spermatogenesis genes in hybrids.

  11. Spermatogenesis is accelerated in the immature Djungarian and Chinese hamster and rat

    NARCIS (Netherlands)

    van Haaster, L. H.; de rooij, D. G.

    1993-01-01

    The rate of progression of spermatogenesis was studied in immature Djungarian and Chinese hamsters and Wistar rats by scoring the most advanced cell types present at various ages after birth. From 15 days of age onward, the most advanced cell types in the Djungarian hamsters were formed at a rate

  12. Age-dependence of relative telomere length profiles during spermatogenesis in man

    DEFF Research Database (Denmark)

    Jørgensen, Pernille Bach; Fedder, Jens; Koelvraa, Steen

    2013-01-01

    by telomere QFISH. Our data revealed no difference in the TL profile during spermatogenesis between younger and older men. All men had a similar profile which strongly resembled the telomerase expression profile found by others. This indicates that the longer telomeres in older men are not caused by a wider...

  13. CLOCK interacts with RANBP9 and is involved in alternative splicing in spermatogenesis.

    Science.gov (United States)

    Yang, Junbao; Zhang, Zhiwei; Zhang, Yingying; Zheng, Xulei; Lu, Yilu; Tao, Dachang; Liu, Yunqiang; Ma, Yongxin

    2018-02-05

    The core circadian gene CLOCK plays an important role in regulating male reproduction. However, the underlying mechanism still remains unclear. In the present study, we executed yeast two-hybrid screening using cDNA fragment of CLOCK PAS A domain as bait, and identified RANBP9 as a novel protein interacting with CLOCK. The interaction between CLOCK and RANBP9 was further validated by in vivo and in vitro assays. Previous studies have confirmed that SF3B3 was a RANBP9 interacting protein. Subsequently, our study also found that CLOCK and SF3B3 can interact with each other by co-immunoprecipitation in mouse testis. In order to dissect the underlying mechanism of CLOCK in spermatogenesis, we also performed RNA-immunoprecipitation followed by high-throughput sequencing (RIP-Seq) in mouse testis. The result of sequence analyses and Gene Ontology enrichment analyses (biological processes) demonstrated that CLOCK can directly bind 186 key mRNA transcripts in mouse spermatogenesis. Taken together, our results firstly showed that CLOCK can interact with RANBP9 and bind with mRNAs, demonstrating that CLOCK is involved in alternative splicing in spermatogenesis. These results reveal a novel mechanism for CLOCK in spermatogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The effect of para-nonylphenol on Japanese eel (Anguilla japonica) spermatogenesis in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Miura, C. [Laboratory of Fish Reproductive Physiology, Faculty of Agriculture, Ehime University, Matsuyama, Ehime 790-8566 (Japan); ' Times Arrow and Biosignaling' PRESTO Japan Science and Technology Agency, Kawaguchi 332-0012 (Japan); Takahashi, N. [Iwate Fisheries Technology Center, Fisheries and Resource Management Division, 3-75-3 Oaza-hirata, Kamaishi, Iwate 026-0001 (Japan); Michino, F. [Laboratory of Fish Reproductive Physiology, Faculty of Agriculture, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Miura, T. [Laboratory of Fish Reproductive Physiology, Faculty of Agriculture, Ehime University, Matsuyama, Ehime 790-8566 (Japan); ' Times Arrow and Biosignaling' PRESTO Japan Science and Technology Agency, Kawaguchi 332-0012 (Japan)

    2005-01-26

    Endocrine disrupters have been recognized to interfere with endocrine systems that regulate reproduction, for example, by mimicking or inhibiting the action of endogenous sex steroid hormones including estradiol-17{beta} (E2). In the present study, we examined the effect of an endocrine disrupter, para-nonylphenol (p-NP) on spermatogenesis, and compared it with the action of E2, using an eel testicular organ culture system. p-NP alone stimulated early spermatogonial renewal in the same manner as E2. Neither induced further progress in spermatogenesis. In the presence of 11-ketotestosterone (11-KT), the major androgen in teleosts, p-NP did not prevent the 11-KT-induced progress in spermatogenesis. However, this treatment enlarged the Sertoli cells. Electron microscopic observation revealed that enlarged Sertoli cells contained well-developed organelles. Moreover, the proportion of germ cells appeared to have decreased as a result of Sertoli cell hypertrophy. These results clearly show that p-NP has an effect on Sertoli cells in the presence of an androgen (11-KT), potentially disturbing 11-KT-induced spermatogenesis.

  15. Recovery of spermatogenesis following testosterone replacement therapy or anabolic-androgenic steroid use

    Science.gov (United States)

    McBride, J Abram; Coward, Robert M

    2016-01-01

    The use of testosterone replacement therapy (TRT) for hypogonadism continues to rise, particularly in younger men who may wish to remain fertile. Concurrently, awareness of a more pervasive use of anabolic-androgenic steroids (AAS) within the general population has been appreciated. Both TRT and AAS can suppress the hypothalamic-pituitary-gonadal (HPG) axis resulting in diminution of spermatogenesis. Therefore, it is important that clinicians recognize previous TRT or AAS use in patients presenting for infertility treatment. Cessation of TRT or AAS use may result in spontaneous recovery of normal spermatogenesis in a reasonable number of patients if allowed sufficient time for recovery. However, some patients may not recover normal spermatogenesis or tolerate waiting for spontaneous recovery. In such cases, clinicians must be aware of the pathophysiologic derangements of the HPG axis related to TRT or AAS use and the pharmacologic agents available to reverse them. The available agents include injectable gonadotropins, selective estrogen receptor modulators, and aromatase inhibitors, but their off-label use is poorly described in the literature, potentially creating a knowledge gap for the clinician. Reviewing their use clinically for the treatment of hypogonadotropic hypogonadism and other HPG axis abnormalities can familiarize the clinician with the manner in which they can be used to recover spermatogenesis after TRT or AAS use. PMID:26908067

  16. Recovery of spermatogenesis following testosterone replacement therapy or anabolic-androgenic steroid use

    Directory of Open Access Journals (Sweden)

    J Abram McBride

    2016-01-01

    Full Text Available The use of testosterone replacement therapy (TRT for hypogonadism continues to rise, particularly in younger men who may wish to remain fertile. Concurrently, awareness of a more pervasive use of anabolic-androgenic steroids (AAS within the general population has been appreciated. Both TRT and AAS can suppress the hypothalamic-pituitary-gonadal (HPG axis resulting in diminution of spermatogenesis. Therefore, it is important that clinicians recognize previous TRT or AAS use in patients presenting for infertility treatment. Cessation of TRT or AAS use may result in spontaneous recovery of normal spermatogenesis in a reasonable number of patients if allowed sufficient time for recovery. However, some patients may not recover normal spermatogenesis or tolerate waiting for spontaneous recovery. In such cases, clinicians must be aware of the pathophysiologic derangements of the HPG axis related to TRT or AAS use and the pharmacologic agents available to reverse them. The available agents include injectable gonadotropins, selective estrogen receptor modulators, and aromatase inhibitors, but their off-label use is poorly described in the literature, potentially creating a knowledge gap for the clinician. Reviewing their use clinically for the treatment of hypogonadotropic hypogonadism and other HPG axis abnormalities can familiarize the clinician with the manner in which they can be used to recover spermatogenesis after TRT or AAS use.

  17. Discovery of piRNAs Pathway Associated with Early-Stage Spermatogenesis in Chicken.

    Directory of Open Access Journals (Sweden)

    Lu Xu

    Full Text Available Piwi-interacting RNAs (piRNAs play a key role in spermatogenesis. Here, we describe the piRNAs profiling of primordial germ cells (PGCs, spermatogonial stem cells (SSCs, and the spermatogonium (Sp during early-stage spermatogenesis in chicken. We obtained 31,361,989 reads from PGCs, 31,757,666 reads from SSCs, and 46,448,327 reads from Sp cells. The length distribution of piRNAs in the three samples showed peaks at 33 nt. The resulting genes were subsequently annotated against the Gene Ontology (GO database. Five genes (RPL7A, HSPA8, Pum1, CPXM2, and PRKCA were found to be involved in cellular processes. Interactive pathway analysis (IPA further revealed three important pathways in early-stage spermatogenesis including the FGF, Wnt, and EGF receptor signaling pathways. The gene Pum1 was found to promote germline stem cell proliferation, but it also plays a role in spermatogenesis. In conclusion, we revealed characteristics of piRNAs during early spermatogonial development in chicken and provided the basis for future research.

  18. Propylthiouracil-induced hypothyroidism delays apoptosis during the first wave of spermatogenesis

    Directory of Open Access Journals (Sweden)

    Doris Silva

    2011-01-01

    Full Text Available Mammalian germ cell apoptosis plays a key role in controlling the correct number of germ cells supported by Sertoli cells during the first wave of spermatogenesis in mammalian puberty. However, little is known about hormonal factors that could influence the rate of germ cell apoptosis during puberty or adulthood. In this work we evaluate germ cell apoptosis under hypothyroidism induced by goitrogen propylthiouracil (PTU during the first wave of spermatogenesis. Neonatally administered PTU promoted a delay in the differentiation of Sertoli cells as evaluated by the expression of clusterin using immunohistochemistry and RT-PCR. Clusterin had different expression levels in control and PTU-treated animals, but under both conditions the highest levels were found in 35-day-old rats. In addition, clusterin displayed a cytoplasmic localization in control testes, but appeared located in the nucleus in PTU-treated animals. The wave of apoptosis (determined by caspase activity and quantification of apoptotic cells characteristic of the first round of spermatogenesis was delayed by at least 10 days in these animals. The expression levels of proapoptotic genes like BAX or BAD were different between control and PTU-treated rats; although in both groups the highest level was found at the same age (days. Thus our results indicate that the characteristic pubertal apoptotic wave during rat spermatogenesis is delayed in neonatal hypothyroid rats.

  19. Role of posttranslational modifications in C. elegans and ascaris spermatogenesis and sperm function.

    Science.gov (United States)

    Miao, Long; L'Hernault, Steven W

    2014-01-01

    Generally, spermatogenesis and sperm function involve widespread posttranslational modification of regulatory proteins in many different species. Nematode spermatogenesis has been studied in detail, mostly by genetic/molecular genetic techniques in the free-living Caenorhabditis elegans and by biochemistry/cell biology in the pig parasite Ascaris suum. Like other nematodes, both of these species produce sperm that use a form of amoeboid motility termed crawling, and many aspects of spermatogenesis are likely to be similar in both species. Consequently, work in these two nematode species has been largely complementary. Work in C. elegans has identified a number of spermatogenesis-defective genes and, so far, 12 encode enzymes that are implicated as catalysts of posttranslational protein modification. Crawling motility involves extension of a single pseudopod and this process is powered by a unique cytoskeleton composed of Major Sperm Protein (MSP) and accessory proteins, instead of the more widely observed actin. In Ascaris, pseudopod extension and crawling motility can be reconstituted in vitro, and biochemical studies have begun to reveal how posttranslational protein modifications, including phosphorylation, dephosphorylation and proteolysis, participate in these processes.

  20. c-ABL gene expression and spermatogenesis : investigations into the possible role of octamer transcription factors

    NARCIS (Netherlands)

    D.N. Meijer (Dies)

    1992-01-01

    textabstractThe work described in this thesis aims at the elucidation of mechanisms that govern cellular differentiation events in male germ cell development (spermatogenesis), especially during the post-meiotic phase (spermiogenesis). and in embryonal carcinoma cells. Chapter II describes

  1. In vitro maintenance of spermatogenesis in Xenopus laevis testis explants cultured in serum-free media

    International Nuclear Information System (INIS)

    Risley, M.S.; Miller, A.; Bumcrot, D.A.

    1987-01-01

    Spermatogenesis has been maintained for extended periods in Xenopus laevis testis explants cultured in serum-free media supplemented with bovine serum albumin, insulin, transferrin, follicle-stimulating hormone, dihydrotestosterone, testosterone, retinol, ascorbate, and tocopherol. The organization of the testis fragments was maintained for 28 days, and all stages of development were present throughout the culture period. 3 H-Thymidine-labeled secondary (Type B) spermatogonia developed in 28 days into spermatids at the acrosomal vesicle stage whereas labeled zygotene spermatocytes became mature spermatids in 28 days. Spermatogonial proliferation also continued in vitro for 28 days. Germ cell differentiation was not dependent upon exogenous testosterone, ascorbate, or tocopherol since 3 H-labeled spermatogonia became mature spermatids in testes cultured 35 days in media lacking these supplements. Autoradiography demonstrated that 55% of the luminal sperm present in explants cultured 10 days had differentiated in vitro. Sperm from testes cultured 10-35 days were similar to sperm from freshly dissected testes with regard to motility and fecundity, and eggs fertilized with sperm from explant cultures developed normally into swimming tadpoles. The results demonstrate the feasibility of maintaining vertebrate spermatogenesis in culture and suggest that in vitro analysis of Xenopus spermatogenesis using defined media may provide important insights into the evolution of regulatory mechanisms in spermatogenesis

  2. The effect of para-nonylphenol on Japanese eel (Anguilla japonica) spermatogenesis in vitro

    International Nuclear Information System (INIS)

    Miura, C.; Takahashi, N.; Michino, F.; Miura, T.

    2005-01-01

    Endocrine disrupters have been recognized to interfere with endocrine systems that regulate reproduction, for example, by mimicking or inhibiting the action of endogenous sex steroid hormones including estradiol-17β (E2). In the present study, we examined the effect of an endocrine disrupter, para-nonylphenol (p-NP) on spermatogenesis, and compared it with the action of E2, using an eel testicular organ culture system. p-NP alone stimulated early spermatogonial renewal in the same manner as E2. Neither induced further progress in spermatogenesis. In the presence of 11-ketotestosterone (11-KT), the major androgen in teleosts, p-NP did not prevent the 11-KT-induced progress in spermatogenesis. However, this treatment enlarged the Sertoli cells. Electron microscopic observation revealed that enlarged Sertoli cells contained well-developed organelles. Moreover, the proportion of germ cells appeared to have decreased as a result of Sertoli cell hypertrophy. These results clearly show that p-NP has an effect on Sertoli cells in the presence of an androgen (11-KT), potentially disturbing 11-KT-induced spermatogenesis

  3. Spermatogenesis-specific features of the meiotic program in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Diane C Shakes

    2009-08-01

    Full Text Available In most sexually reproducing organisms, the fundamental process of meiosis is implemented concurrently with two differentiation programs that occur at different rates and generate distinct cell types, sperm and oocytes. However, little is known about how the meiotic program is influenced by such contrasting developmental programs. Here we present a detailed timeline of late meiotic prophase during spermatogenesis in Caenorhabditis elegans using cytological and molecular landmarks to interrelate changes in chromosome dynamics with germ cell cellularization, spindle formation, and cell cycle transitions. This analysis expands our understanding C. elegans spermatogenesis, as it identifies multiple spermatogenesis-specific features of the meiotic program and provides a framework for comparative studies. Post-pachytene chromatin of spermatocytes is distinct from that of oocytes in both composition and morphology. Strikingly, C. elegans spermatogenesis includes a previously undescribed karyosome stage, a common but poorly understood feature of meiosis in many organisms. We find that karyosome formation, in which chromosomes form a constricted mass within an intact nuclear envelope, follows desynapsis, involves a global down-regulation of transcription, and may support the sequential activation of multiple kinases that prepare spermatocytes for meiotic divisions. In spermatocytes, the presence of centrioles alters both the relative timing of meiotic spindle assembly and its ultimate structure. These microtubule differences are accompanied by differences in kinetochores, which connect microtubules to chromosomes. The sperm-specific features of meiosis revealed here illuminate how the underlying molecular machinery required for meiosis is differentially regulated in each sex.

  4. Autonomous Mission Operations

    Data.gov (United States)

    National Aeronautics and Space Administration — The AES Autonomous Mission Operations project will develop understanding of the impacts of increasing communication time delays on mission operations and develop...

  5. Semi-Autonomous Systems Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — VisionThe Semi-Autonomous Systems Lab focuses on developing a comprehensive framework for semi-autonomous coordination of networked robotic systems. Semi-autonomous...

  6. Testing for autonomic neuropathy

    DEFF Research Database (Denmark)

    Hilsted, J

    1984-01-01

    of the disease, and may be nonspecific. A number of recently developed quantifiable and reproducible autonomic nerve function tests are reviewed, with emphasis on the physiological basis of the tests and on practical applicability. Finally, diagnostic criteria, based on autonomic nerve function tests...

  7. Cardiovascular Autonomic Neuropathy in Systemic Lupus Erythematosus.

    Science.gov (United States)

    Alam, Md Mahboob; Das, Pinaki; Ghosh, Parasar; Zaman, Md Salim Uz; Boro, Madhusmita; Sadhu, Manika; Mazumdar, Ardhendu

    2015-01-01

    Objective is to evaluate cardiovascular autonomic function in SLE by simple non-invasive tests. A case control study was carried out involving 18-50 yrs old previously diagnosed SLE patients and same number of age and sex-matched controls. Parasympathetic function was assessed by heart rate (HR) response to Valsalva maneuver, deep breathing and standing. Sympathetic function was evaluated by blood pressure response to standing and sustained hand-grip test (HGT). There were 50 female SLE patients. They had significantly higher minimum resting HR and diastolic blood pressure (DBP). HR variation with deep breathing, expiratory inspiratory ratio, 30:15 ratio and DBP change in response to HGT were significantly lower inpatients compared to controls. Thirty patients (60%) had at least one abnormal or two borderline test results indicating autonomic impairment of which 27 had parasympathetic dysfunction and 7 had sympathetic dysfunction. Autonomic dysfunction is common in SLE with higher prevalence of parasympathetic impairment.

  8. MicroRNA biogenesis is required for mouse primordial germ cell development and spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Katsuhiko Hayashi

    2008-03-01

    Full Text Available MicroRNAs (miRNAs are critical regulators of transcriptional and post-transcriptional gene silencing, which are involved in multiple developmental processes in many organisms. Apart from miRNAs, mouse germ cells express another type of small RNA, piwi-interacting RNAs (piRNAs. Although it has been clear that piRNAs play a role in repression of retrotransposons during spermatogenesis, the function of miRNA in mouse germ cells has been unclear.In this study, we first revealed the expression pattern of miRNAs by using a real-time PCR-based 220-plex miRNA expression profiling method. During development of germ cells, miR-17-92 cluster, which is thought to promote cell cycling, and the ES cell-specific cluster encoding miR-290 to -295 (miR-290-295 cluster were highly expressed in primordial germ cells (PGCs and spermatogonia. A set of miRNAs was developmentally regulated. We next analysed function of miRNA biogenesis in germ cell development by using conditional Dicer-knockout mice in which Dicer gene was deleted specifically in the germ cells. Dicer-deleted PGCs and spermatogonia exhibited poor proliferation. Retrotransposon activity was unexpectedly suppressed in Dicer-deleted PGCs, but not affected in the spermatogonia. In Dicer-deleted testis, spermatogenesis was retarded at an early stage when proliferation and/or early differentiation. Additionally, we analysed spermatogenesis in conditional Argonaute2-deficient mice. In contrast to Dicer-deficient testis, spermatogenesis in Argonaute2-deficient testis was indistinguishable from that in wild type.These results illustrate that miRNAs are important for the proliferation of PGCs and spermatogonia, but dispensable for the repression of retrotransposons in developing germ cells. Consistently, miRNAs promoting cell cycling are highly expressed in PGCs and spermatogonia. Furthermore, based on normal spermatogenesis in Argonaute2-deficient testis, the critical function of Dicer in spermatogenesis is

  9. Broad sustainability versus sustainability

    International Nuclear Information System (INIS)

    Hueting, R.; Reijnders, L.

    2002-01-01

    The notion sustainability has many definitions and interpretations, which are not always in favor of the development of sustainability. Therefore, a narrow definition of sustainability is required [nl

  10. Testicular dysgenesis syndrome comprises some but not all cases of hypospadias and impaired spermatogenesis

    DEFF Research Database (Denmark)

    Jørgensen, N; Rajpert-De Meyts, Ewa; Main, K M

    2010-01-01

    In 2001, when the testicular dysgenesis syndrome (TDS) concept was proposed, it suggested that impaired development of foetal testes could lead to increased risks of cryptorchidism, hypospadias, decreased spermatogenesis or testis cancer. The TDS concept links the pathogenesis of the four disorders...... are most likely caused by TDS. However, the frequency of the syndrome in the general population and to what extent poor semen quality and hypospadias are actually biologically related through a foetal mechanism remain unresolved. Hypospadias and impaired spermatogenesis can be classified as TDS if combined...... with cryptorchidism or TGCC. By contrast, recent studies demonstrated that among men with isolated hypospadias, only a fraction of cases are linked to TDS. There is no doubt that TDS contributes to impaired semen quality. This is most obvious for cases with visible dysgenetic features in testis histology...

  11. Nucleolar Persistence: Peculiar Characteristic of Spermatogenesis of the Vectors of Chagas Disease (Hemiptera, Triatominae).

    Science.gov (United States)

    Madeira, Fernanda Fernandez; Borsatto, Kelly Cristine; Lima, Anna Claudia Campaner; Ravazi, Amanda; de Oliveira, Jader; da Rosa, João Aristeu; de Azeredo-Oliveira, Maria Tercília Vilela; Alevi, Kaio Cesar Chaboli

    2016-11-02

    All species of triatomines are considered potential vectors of Chagas disease and the reproductive biology of these bugs has been studied by different approaches. In 1999, nucleolar persistence during meiosis was observed in the subfamily for the first time. Recently, it has been observed that all species within the genus Rhodnius exhibit the same phenomenon, suggesting that it may be a synapomorphy of the triatomines. Thus, this article aims to analyze the nucleolar behavior during spermatogenesis of 59 triatomine species. All analyzed species exhibited nucleolar persistence during meiosis. Recently, it has been suggested that nucleolar persistence may be fundamental for the spermatogenesis of these vectors, since it is related to the formation of the chromatoid body. Therefore, we emphasize that this phenomenon is a peculiarity of the Triatominae subfamily and that further studies are required to analyze whether the nucleolar material that persists is active. © The American Society of Tropical Medicine and Hygiene.

  12. Testis-Specific Histone Variant H3t Gene Is Essential for Entry into Spermatogenesis

    Directory of Open Access Journals (Sweden)

    Jun Ueda

    2017-01-01

    Full Text Available Cellular differentiation is associated with dynamic chromatin remodeling in establishing a cell-type-specific epigenomic landscape. Here, we find that mouse testis-specific and replication-dependent histone H3 variant H3t is essential for very early stages of spermatogenesis. H3t gene deficiency leads to azoospermia because of the loss of haploid germ cells. When differentiating spermatogonia emerge in normal spermatogenesis, H3t appears and replaces the canonical H3 proteins. Structural and biochemical analyses reveal that H3t-containing nucleosomes are more flexible than the canonical nucleosomes. Thus, by incorporating H3t into the genome during spermatogonial differentiation, male germ cells are able to enter meiosis and beyond.

  13. GANGGUAN SPERMATOGENESIS SETELAH PEMBERIAN MONOSODIUM GLUTAMAT PADA MENCIT (MUS MUSCULUS L.

    Directory of Open Access Journals (Sweden)

    A.A.SG.A SUKMANINGSIH

    2011-12-01

    Full Text Available This study was conducted to investigate the effect of monosodium glutamate (MSG on spermatogenesis of male experimental mice.using 32 twelve-week old mice. They were divided randomly into 4 groups, each group consisted of 8 mice. One group was used as control, three groups were used as treatment, which received 1.5 mg/g body weight/day, 3 mg/g body weight/day and 4.5 mg/g body weight/day of MSG solution in destilled water for 35 days. The result showed that MSG treatment led to disturbance on spermatogenesis by reduction in some of the parameter studied. There was a significant (p 0.05.

  14. The effect of the preparation TV-68 on the spermatogenesis of rat (autoradiographic studies)

    International Nuclear Information System (INIS)

    Anastasova-Krysteva, M.; Kyncheva, L.

    1976-01-01

    Male mature rats were treated per os with TV-68 (a sexual function stimulating drug) and intraperitoneally with 3 H-thymidine during 7 and 12 days. By means of statistical count of labelled cells in seminiferous tubules a considerable increase of DNA replicating cells in experimental animals was established. The higher percentage of labelled cells reveales a stimulating effect of the TV-68 concerning the spermatogonial proliferation, some acceleration of the meiosis and positive influence of spermatogenesis as a whole. (author)

  15. Ultrastructure of spermatogenesis, spermatozoon and processes of testicular regression and recrudescence in Eptesicus furinalis (Chiroptera: Vespertilionidae).

    Science.gov (United States)

    Bueno, Larissa M; Beguelini, Mateus R; Comelis, Manuela T; Taboga, Sebastião R; Morielle-Versute, Eliana

    2014-08-01

    Studies have shown that the annual reproductive cycle of Eptesicus furinalis includes at least one period of total testicular regression. Thus, this study aimed to evaluate their reproductive cycle ultrastructurally. The annual reproductive cycle was divided into four periods: active, regressing, regressed and recrudescence. The active period was similar to that of other bats, including the completion of spermatogenesis with three main types of spermatogonia (Ad, Ap and B) and 12 steps in the process of spermatid differentiation. However, its spermatozoa differed in that outer dense fibers 1, 5, 6 and 9 are larger than the others and due to the presence of what is likely a probably genera-specific bulging in the anterior portion. In the regressing period, Sertoli cell nuclei migrate to the basal compartment with the nuclei close to the basal lamina. The basal compartment had a more compact appearance than the adluminal compartment, with relaxed cellular connections. In the regressed period, spermatogenesis ceased; the seminiferous epithelium was composed only of Sertoli cells and three types of spermatogonia: types Ad, 1 and 2. In the recrudescence period, spermatogenesis restarted, with the process of reactivation divided into three phases: early, medial and late recrudescence. In conclusion, our study described the process of spermatogenesis and the ultrastructure of the spermatozoa and confirmed the presence of a process of total testicular regression in the annual cycle of E. furinalis. We characterize distinct morphologic variations in the ultrastructure of the testicular cells during the four different periods of the annual reproductive cycle. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. MicroRNA-184 downregulates nuclear receptor corepressor 2 in mouse spermatogenesis.

    Science.gov (United States)

    Wu, Jingwen; Bao, Jianqiang; Wang, Li; Hu, Yanqin; Xu, Chen

    2011-10-24

    There have been increasing attentions on the role of small RNAs, especially microRNAs in post-transcriptional gene regulation during spermatogenesis. MicroRNA-184 (miR-184) has been shown to be mainly expressed in the testis and brain, and that its expression levels are by far the highest in the testis. However, the role of miR-184 in mammalian spermatogenesis remains unclear. In this study, we demonstrated that miR-184 levels were increased during mouse postnatal testis development. Specifically, miR-184 expression was restricted to the germ cells from spermatogonia to round spermatids. Overexpression of miR-184 promoted the proliferation of a germ cell line, GC-1spg. Moreover, miR-184 downregulated nuclear receptor corepressor 2 (Ncor2) by targeting its 3' untranslated region through inhibiting NCOR2 protein translation. MiR-184 may be involved in the post-transcription regulation of mRNAs such as Ncor2 in mammalian spermatogenesis.

  17. Temporal germ cell development strategy during continuous spermatogenesis within the montane lizard, Sceloporus bicanthalis (Squamata; Phrynosomatidae).

    Science.gov (United States)

    Gribbins, Kevin; Anzalone, Marla; Collier, Matthew; Granados-González, Gisela; Villagrán-Santa Cruz, Maricela; Hernández-Gallegos, Oswaldo

    2011-10-01

    Sceloporus bicanthalis is a viviparous lizard that lives at higher elevations in Mexico. Adult male S. bicanthalis were collected (n = 36) from the Nevado de Toluca, Mexico (elevation is 4200 m) during August to December, 2007 and January to July, 2008. Testes were extracted, fixed in Trumps, and dehydrated in a graded series of ethanol. Tissues were embedded, sectioned (2 μm), stained, and examined via a light microscope to determine the spermatogenic developmental strategy of S. bicanthalis. In all months examined, the testes were spermiogenically active; based on this, plus the presence of sperm in the lumina of seminiferous tubules, we inferred that S. bicanthalis had year-round or continuous spermatogenesis, unlike most reptiles that occupy a temperate or montane habitat. It was recently reported that seasonally breeding reptiles had a temporal germ cell development strategy similar to amphibians, where germ cells progress through spermatogenesis as a single population, which leads to a single spermiation event. This was much different than spatial development within the testis of other derived amniotes. We hypothesized that germ cell development was temporal in S. bicanthalis. Therefore, we wanted to determine whether reptiles that practice continuous spermatogenesis have a mammalian-like spatial germ cell development, which is different than the typical temperate reptile exhibiting a temporal development. In the present study, S. bicanthalis had a temporal development strategy, despite its continuous spermatogenic cycle, making them similar to tropical anoles. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Anti-Müllerian hormone as a seminal marker for spermatogenesis in non-obstructive azoospermia.

    Science.gov (United States)

    Fénichel, P; Rey, R; Poggioli, S; Donzeau, M; Chevallier, D; Pointis, G

    1999-08-01

    Anti-Müllerian hormone (AMH) also known as Müllerian inhibiting substance or factor, is a Sertoli cell-secreted glycoprotein responsible in male embryos for Müllerian duct regression. However, its role in adults remains unknown. AMH seminal concentrations have been evaluated using an enzyme-linked immunoassay in three groups of young men: group 1, fertile donors (n = 18); group 2, obstructive azoospermia (n = 9) after vasectomy or associated with deferent duct agenesia; and group 3, non-obstructive azoospermia with spermatogenesis deficiency and normal karyotype (n = 23). AMH was present in seminal plasma of most fertile donors at concentrations ranging from undetectable (testicular origin. In non-obstructive azoospermia (group 3), seminal AMH concentration was lower (range testicular biopsies revealed that undetectable AMH found in 14 cases was associated in 11 of them with lack of spermatozoa, while detectable concentrations of AMH (10-68.5 pmol/l) found in nine cases were associated in seven of them with persistent spermatogenesis. In the adult, AMH is secreted preferentially towards the seminiferous lumen. Although its relationship with spermatogenesis requires further investigation, our results suggest that seminal AMH may represent a non-invasive marker of persistent hypospermatogenesis in cases of non-obstructive azoospermia which may indicate the likely success of testicular spermatozoa recovery before intracytoplasmic sperm injection.

  19. Fourier Transform Infrared Spectroscopy: A Potential Technique for Noninvasive Detection of Spermatogenesis

    Science.gov (United States)

    Gilany, Kambiz; Pouracil, Roudabeh Sadat Moazeni; Sadeghi, Mohammad Reza

    2014-01-01

    Background The seminal plasma is an excellent source for noninvasive detection of spermatogenesis. The seminal plasma of normospermic and azoospermic men has been analyzed for detection of spermatogenesis. Methods Optical spectroscopy (Attenuated Total Reflectance-Infrared spectroscopy (ATR-IR) and Fourier Transform infrared spectroscopy (FT-IR) has been used to analyze the seminal plasma and the metabolome of seminal plasma for detection of spermatogenesis. Results The seminal plasma of normospermic and azoospermic men has been analyzed by ATR-IR. The results show that there is a pattern variation in the azoospermic men compared to normospermic men. However, the seminal plasma is too complex to show significant pattern variation. Therefore, the metabolome which is a subcomponent of the seminal plasma was analyzed. The seminal plasma metabolome of normospermic and azoospermic men has been analyzed by FT-IR. A significant pattern change was observed. The data combined with chemometrics analysis showed that significant changes are observed at metabolome level. Conclusion We suggest that FT-IR has the potential as a diagnostic tool instead of testicular biopsy. PMID:24523955

  20. Testicular development and establishment of spermatogenesis in Nili-Ravi buffalo bulls.

    Science.gov (United States)

    Ahmad, N; Umair, S; Shahab, M; Arslan, M

    2010-01-01

    Fifteen longitudinally reared Nili-Ravi buffalo bulls (Bubalus bubalis) were slaughtered at 1, 6, 12, 18, and 24 mo of age (n=3 per group) to observe testicular development and to examine qualitatively the establishment of spermatogenesis. With the age held constant, scrotal circumference and testes weight were correlated (0.95; Pfashion (57microm at 1 mo and 178microm at 24 mo), and the lumen formed at 12 mo of age. Differentiation of basal indifferent supporting cells to Sertoli cells started at 6 mo, and formation of Sertoli cells completed near 12 mo of age. Gonocytes predominated at 1 mo, but by 12 mo, most had been replaced by spermatogonia, thus rapid proliferation of tubular contents occurred at 12 mo (testes weight=75g). Spermatocytes were first observed at 12 mo, and their number increased through 18 and 24 mo. Establishment of spermatogenesis, as reflected by appearance of significant number of spermatids, occurred by 18 mo of age (testes weight 122g). Thus, the establishment of spermatogenesis was progressive from birth, and marked changes were observed during the last 6 mo.

  1. Fourier transform infrared spectroscopy: a potential technique for noninvasive detection of spermatogenesis.

    Science.gov (United States)

    Gilany, Kambiz; Pouracil, Roudabeh Sadat Moazeni; Sadeghi, Mohammad Reza

    2014-01-01

    The seminal plasma is an excellent source for noninvasive detection of spermatogenesis. The seminal plasma of normospermic and azoospermic men has been analyzed for detection of spermatogenesis. Optical spectroscopy (Attenuated Total Reflectance-Infrared spectroscopy (ATR-IR) and Fourier Transform infrared spectroscopy (FT-IR) has been used to analyze the seminal plasma and the metabolome of seminal plasma for detection of spermatogenesis. The seminal plasma of normospermic and azoospermic men has been analyzed by ATR-IR. The results show that there is a pattern variation in the azoospermic men compared to normospermic men. However, the seminal plasma is too complex to show significant pattern variation. Therefore, the metabolome which is a subcomponent of the seminal plasma was analyzed. The seminal plasma metabolome of normospermic and azoospermic men has been analyzed by FT-IR. A significant pattern change was observed. The data combined with chemometrics analysis showed that significant changes are observed at metabolome level. We suggest that FT-IR has the potential as a diagnostic tool instead of testicular biopsy.

  2. Characterization of fucosyltransferase activity during mouse spermatogenesis: Evidence for a cell surface fucosyltransferase

    Energy Technology Data Exchange (ETDEWEB)

    Cardullo, R.A.; Armant, D.R.; Millette, C.F. (Harvard Medical School, Boston, MA (USA))

    1989-02-21

    Fucosyltransferase activity was quantified in mouse germ cells at different stages of spermatogenesis. Specifically, fucosyltransferase activities of pachytene spermatocytes, round spermatids, and cauda epididymal sperm were compared. Fucosyltranferase activity of mixed germ cells displayed an apparent V{sub max} of 17 pmol (mg of protein){sup {minus}1} min{sup {minus}1} and an apparent K{sub m} of approximately 13 {mu}M for GDP-L-({sup 14}C)fucose in the presence of saturating amounts of asialofetuin at 33{degree}C. Under these conditions, cellular fucosyltransferase activity was found to increase during spermatogenesis. In agreement with assays of intact cells, examination of subcellular fractions indicated that a large fraction of fucosyltransferase activity was associated with the cell surface. The fraction of fucosyltransferase activity that was associated with the cell surface progressively increased throughout spermatogenesis and epididymal maturation so that nearly all of the fucosyltransferase in epididymal sperm was on the cell surface. Specifically, by comparison of activities in the presence and absence of the detergent NP-40, the fraction of fucosyltransferase activity that was associated with the cell surface in pachytene spermatocytes, round spermatids, and epididymal sperm was 0.36, 0.5, and 0.85, respectively. These results suggest that a cell surface fucosyltransferase may be important during differentiation of spermatogenic cells in the testis as well as during epididymal maturation and fertilization.

  3. Autonomous Systems and Operations

    Data.gov (United States)

    National Aeronautics and Space Administration — The AES Autonomous Systems and Operations (ASO) project will develop an understanding of the impacts of increasing communication time delays on mission operations,...

  4. Autonomous Systems: Habitat Automation

    Data.gov (United States)

    National Aeronautics and Space Administration — The Habitat Automation Project Element within the Autonomous Systems Project is developing software to automate the automation of habitats and other spacecraft. This...

  5. Autonomous Propellant Loading Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The AES Autonomous Propellant Loading (APL) project consists of three activities. The first is to develop software that will automatically control loading of...

  6. Autonomic Nervous System in Paralympic Athletes with Spinal Cord Injury.

    Science.gov (United States)

    Walter, Matthias; Krassioukov, Andrei V

    2018-05-01

    Individuals sustaining a spinal cord injury (SCI) frequently suffer from sensorimotor and autonomic impairment. Damage to the autonomic nervous system results in cardiovascular, respiratory, bladder, bowel, and sexual dysfunctions, as well as temperature dysregulation. These complications not only impede quality of life, but also affect athletic performance of individuals with SCI. This article summarizes existing evidence on how damage to the spinal cord affects the autonomic nervous system and impacts the performance in athletes with SCI. Also discussed are frequently used performance-enhancing strategies, with a special focus on their legal aspect and implication on the athletes' health. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Highly Autonomous Systems Workshop

    OpenAIRE

    Doyle, Richard; Rasmussen, Robert; Man, Guy; Patel, Keyur

    1998-01-01

    Researchers and technology developers from the National Aeronautics and Space Administration (NASA), other government agencies, academia, and industry recently met in Pasadena, California, to take stock of past and current work and future challenges in the application of AI to highly autonomous systems. The meeting was catalyzed by new opportunities in developing autonomous spacecraft for NASA and was in part a celebration of the fictional birth year of the HAL-9000 computer.

  8. Autonomous Intersection Management

    Science.gov (United States)

    2009-12-01

    and analyzing my algorithms for correctness and rigor. Third, Tarun Nimmagadda, for creating the first mixed simulation using my simulator. In addition...Agent Systems, 10(2):131–164, March 2005. [Beeson et al., 2008] Patrick Beeson, Jack O’Quin, Bartley Gillan, Tarun Nimma- gadda, Mickey Ristroph, David...autonomous vehicles at intersections. IEEE Intelligent Systems, 13(3):82–86, May 1998. [Nimmagadda, 2009] Tarun Nimmagadda. Building an autonomous ground

  9. Autonomous Star Tracker Algorithms

    DEFF Research Database (Denmark)

    Betto, Maurizio; Jørgensen, John Leif; Kilsgaard, Søren

    1998-01-01

    Proposal, in response to an ESA R.f.P., to design algorithms for autonomous star tracker operations.The proposal also included the development of a star tracker breadboard to test the algorithms performances.......Proposal, in response to an ESA R.f.P., to design algorithms for autonomous star tracker operations.The proposal also included the development of a star tracker breadboard to test the algorithms performances....

  10. [Spermatogenesis of pulsatile gonadotropin-releasing hormone infusion versus gonadotropin therapy in male idiopathic hypogonadotropic hypogonadism].

    Science.gov (United States)

    Huang, Bingkun; Mao, Jiangfeng; Xu, Hongli; Wang, Xi; Liu, Zhaoxiang; Nie, Min; Wu, Xueyan

    2015-05-26

    To compare the efficacies of pulsatile gonadotropin-releasing hormone (GnRH) versus human chorionic gonadotropin/human menopausal gonadotropin (HCG/HMG) for spermatogenesis in male idiopathic hypogonadotropic hypogonadism (IHH). For this retrospective study, a total of 92 male IHH outpatients from May 2010 to October 2014 were recruited and categorized into GnRH (n = 40) and HCG/HMG (n = 52) groups. Each subject selected one specific therapy voluntarily. The gonadotropin levels were measured in the first week and monthly post-treatment in GnRH group. And serum total testosterone (TT), testicular volume (TV) and rate of spermatogenesis were observed monthly post-treatment in two groups. Spermatogenesis, TT and TV were compared between two groups. All IHH patients were treated for over 3 months. The median follow-up periods in GnRH and HCG/HMG groups was 8.2 (3.0-18.4) and 9.2 (3.0-18.6) months respectively (P = 0.413). In GnRH group, LH ((0.5 ± 0.6) vs (3.4 ± 2.4) U/L, P < 0.01) and FSH ((1.3 ± 1.1) vs (5.8 ± 3.8) U/L, P < 0.01) increased after 1-week treatment. In GnRH group, at the end of follow-up, TT ((1.0 ± 1.0) vs (7.4 ± 5.2) nmol/L, P < 0.01) and TV ((2.3 ± 1.5) vs (8.1 ± 4.0) ml, P < 0.01) significantly increased compared to baseline. In HCG/HMG group, TT ((0.8 ± 0.6) vs (14.4 ± 8.0) nmol/L, P < 0.01) and TV ((2.3 ± 2.1) vs (7.6 ± 4.2) ml, P < 0.01) significantly increased after therapy. The success rate of spermatogenesis was 50.0% (20/40) in GnRH group versus 28.8% (15/52) in HCG/HMG group (P = 0.038). GnRH group required a shorter treatment time for initial sperm appearance than HCG/HMG group ((6.5 ± 3.1) vs (10.8 ± 3.7) months, P = 0.001). Pulsatile GnRH requires a shorter time for initiation of spermatogenesis than gonadotropin therapy in IHH male patients.

  11. [Idiopathic autonomic neuropathy (pandysautonomia)].

    Science.gov (United States)

    Jankowicz, E; Drozdowski, W; Pogumirski, J

    2001-01-01

    On the basis of current literature, clinical and neuropathologic features of idiopathic autonomic neuropathy is presented. Idiopathic autonomic neuropathy is a disease characterized by acute or subacute onset, monophasic course over a period of several years, it is often preceded by an infection. The spectrum of autonomic changes ranges from cholinergic or adrenergic dysfunction to pandysautonomia, leading to heterogeneity of its clinical features. Possible sympathetic system abnormalities found in autonomic neuropathy are: poor pupillary response to light in darkness, orthostatic hypotension leading to syncope, hypotension without compensatory tachycardia, ejaculation disturbances and vasomotor instability. Possible parasympathetic dysfunctions are: salivation and lacrimation disturbances, absent pupillary constriction to light and near gaze, gastrointestinal tract immobility and impairment of gastrointestinal function, atonic bladder with large residual volume, erectile impotence. Pandysautonomia is thought to result from an immune mediated mechanism and responds well to plasmaferesis and intravenous immunoglobin therapy leading to gradual, sometimes not full, recovery. Moreover in this article we pay attention to the clinical value of many tests like cardiovascular or pharmacological studies in the diagnosis of pandysautonomia and in differentiation of pre- and postganglionic changes. In order to diagnose idiopathic autonomic neuropathy one has to rule out a large number of diseases with autonomic dysfunction e.g.: diabetes, malignant neoplasms, acute intermittent porphyria, Shy-Drager syndrome, Riley-Day's dysautonomia, Parkinson's disease, amyloidosis and others.

  12. Myosin Va participates in acrosomal formation and nuclear morphogenesis during spermatogenesis of Chinese mitten crab Eriocheir sinensis.

    Directory of Open Access Journals (Sweden)

    Xiao Sun

    Full Text Available BACKGROUND: The Chinese mitten crab Eriocheir sinensis belongs to the Class Crustacea, Decapoda, Brachyura. The spermatozoon of this species is of aflagellated type, it has a spherical acrosome surrounded by the cup-shaped nucleus, which are unique to brachyurans. For the past several decades, studies on the spermatogenesis of the mitten crab mainly focus on the morphology. Compared with the extensive study of molecular mechanism of spermatogenesis in mammals, relatively less information is available in crustacean species. Myosin Va, a member of Class V myosin, has been implicated in acrosome biogenesis and vesicle transport during spermatogenesis in mammals. In the present study we demonstrate the expression and cellular localization of myosin Va during spermatogenesis in E. sinensis. METHODOLOGY/PRINCIPAL FINDINGS: Western blot demonstrated that myosin Va is expressed during spermatogenesis. Immunocytochemical and ultrastructural analyses showed that myosin Va mainly localizes in the cytoplasm in spermatocytes. At the early stage of spermiogenesis, myosin Va binds to the endoplasmic reticulum vesicle (EV and proacrosomal granule (PG. Subsequently, myosin Va localizes within the proacrosomal vesicle (PV formed by PG and EV fusion and locates in the membrane complex (MC at the mid spermatid stage. At the late spermatid stage, myosin Va is associated with the shaping nucleus and mitochondria. In mature spermatozoon, myosin Va predominates in acrosomal tubule (AT and nucleus. CONCLUSIONS/SIGNIFICANCE: Our study demonstrates that myosin Va may be involved in acrosome biogenesis and nuclear morphogenesis during spermatogenesis in E. sinensis. Considering the distribution and molecular characteristics of myosin Va, we also propose a hypothesis of AT formation in this species. It is the first time to uncover the role of myosin Va in crustacean spermatogenesis.

  13. Autonomous surveillance for biosecurity.

    Science.gov (United States)

    Jurdak, Raja; Elfes, Alberto; Kusy, Branislav; Tews, Ashley; Hu, Wen; Hernandez, Emili; Kottege, Navinda; Sikka, Pavan

    2015-04-01

    The global movement of people and goods has increased the risk of biosecurity threats and their potential to incur large economic, social, and environmental costs. Conventional manual biosecurity surveillance methods are limited by their scalability in space and time. This article focuses on autonomous surveillance systems, comprising sensor networks, robots, and intelligent algorithms, and their applicability to biosecurity threats. We discuss the spatial and temporal attributes of autonomous surveillance technologies and map them to three broad categories of biosecurity threat: (i) vector-borne diseases; (ii) plant pests; and (iii) aquatic pests. Our discussion reveals a broad range of opportunities to serve biosecurity needs through autonomous surveillance. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  14. JMJD1C Exhibits Multiple Functions in Epigenetic Regulation during Spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Ryusuke Nakajima

    Full Text Available Jmjd1C is one of the Jmjd1 family genes that encode putative demethylases against histone H3K9 and non-histone proteins and has been proven to play an indispensable role in mouse spermatogenesis. Here, we analyzed a newly-bred transgenic mouse strain carrying a Jmjd1C loss-of-function allele in which a β-geo cassette was integrated into the intron of the Jmjd1C locus. Jmjd1C gene-trap homozygous testes exhibited malformations in postmeiotic processes and a deficiency in the long-term maintenance of undifferentiated spermatogonia. Some groups of spermatids in the homozygous testis showed abnormal organization and incomplete elongation from the first wave of spermatogenesis onwards. Moreover, histone H4K16 acetylation, which is required for the onset of chromatin remodeling, appeared to be remarkably decreased. These effects may not have been a result of the drastic decrease in gene expression related to the events but instead may have been due to the lack of interaction between JMJD1C and its partner proteins, such as MDC1 and HSP90. Additionally, significant decreases in Oct4 expression and NANOG- and OCT4-expressing spermatogonia were found in the Jmjd1C homozygous mature testis, suggesting that JMJD1C may participate in the maintenance of spermatogonial stem cell self-renewal by up-regulating Oct4 expression. These results indicate that JMJD1C has multiple functions during spermatogenesis through interactions with different partners during the spermatogenic stages.

  15. A potential role for the clathrin adaptor GGA in Drosophila spermatogenesis

    Directory of Open Access Journals (Sweden)

    Carmichael Jenny

    2011-05-01

    Full Text Available Abstract Background GGAs (Golgi-localised, γ-ear containing, ADP ribosylation factor-binding are a family of clathrin adaptors that sort a number of biologically important transmembrane proteins into clathrin-coated vesicles. Knockout and knockdown studies to determine GGA function are confounded by the fact that there are 3 GGA genes in mammalian cells. Thus Drosophila melanogaster is a useful model system to study tissue expression profiles and knockdown phenotypes as there is a single GGA ortholog. Results Here we have quantified protein expression in Drosophila and show that there is >3-fold higher expression of GGA in male flies relative to female flies. In female flies the majority of GGA expression is in the head. In male flies GGA is not only expressed at high levels in the head but there is a gender specific increased expression which is due to the abundant expression of GGA in the testes. Using a highly specific antibody we have localised endogenous GGA protein in testes squashes, and visualised it in somatic and germ line cells. We show that GGA is expressed during multiple stages of sperm development, and co-stains with a marker of the trans-Golgi Network. This is most striking at the acroblast of early spermatids. In spite of the high expression of GGA in testes, knocking down its expression by >95% using transgenic RNAi fly lines did not affect male fertility. Therefore spermatogenesis in the male flies appears to progress normally with Conclusion In Drosophila we have uncovered a potential role for GGA in the testes of male flies. The gender specific higher expression of GGA, its specific enrichment in testes and its localisation to developing spermatocytes and at the acroblast of spermatids supports a role for GGA function in Drosophila spermatogenesis, even though spermatogenesis still occurs when GGA expression is depleted to

  16. Long-term (6-wk) hindlimb suspension inhibits spermatogenesis in adult male rats

    Science.gov (United States)

    Tash, Joseph S.; Johnson, Donald C.; Enders, George C.

    2002-01-01

    The International Space Station will allow extended habitation in space and long-term exposure to microgravity (microG). A concern is the impact of long-term microG exposure on the ability of species to reproduce. The model often used to simulate microG is rat hindlimb suspension (HLS), where the hindlimbs are elevated above the cage floor with a tail harness. Experiments described here are the first to examine the effect of long-term HLS on testicular function in adult male rats. Free-roaming (controls), animals with only the tail harnessed but hindlimbs in contact with the cage floor (TO), and HLS animals were tested for 6 wk. Cryptorchidism was prevented in TO and HLS animals by partial constriction of the inguinal canal with sutures. All parameters were compared at the end of the 6-wk experiment. Testicular weights and spermatogenesis were significantly reduced by HLS, such that no spermatogenic cells beyond round spermatids were present and epididymides were devoid of mature sperm. In many tubules, loss of all germ cells, except a few spermatogonia, resulting in histopathology similar to the Sertoli cell, was observed. Spermatogenesis appeared unaffected in control and TO animals. Sertoli and Leydig cell appearance, testosterone, luteinizing hormone, and follicle-stimulating hormone levels, and epididymal and seminal vesicle weight were unchanged by HLS. Cortisone was not elevated by HLS; thus stress may not be a factor. These results demonstrate that spermatogenesis is severely inhibited by long-term HLS, whereas testicular androgen production is not. These results have significant implications regarding serious effects of long-term exposure to microG on the reproductive capability of scrotal mammals, including humans.

  17. Spermatogenesis of male catfish Clarias sp. fed diet supplemeted with purwoceng extract

    Directory of Open Access Journals (Sweden)

    Poppy Dea Bertha

    2016-02-01

    Full Text Available ABSTRACT Purwoceng Pimpinella alpina Molk has been a commercial medicinal plant that their root could be used as aphrodisiac, diuretic, and body fit enhancer. This research was performed to evaluated the effect of purwoceng on spermatogenesis of the male catfish Clarias sp. consisted of testis weight, gonado somatic index (GSI, and spermatocrite levels. The treatment comprised administering purwoceng extract through the feed at a dose of 0; 2.5; 5; 7.5 g/kg of feed. Experimental fish used were male catfish Clarias sp. with initial body weight of 200–300 g at the density of 10 fish/tank. Male catfish were maintained in tank sized 2×1,5×1 m3, filled with water at 60–70 cm deep. The result showed that purwoceng extract at a dose of 5 g/kg mixed in the feed increased testis weight, GSI values, and spermatocrite levels in adult male catfish. Keywords: purwoceng extract, spermatogenesis, catfish  ABSTRAK Purwoceng Pimpinella alpina Molk merupakan tanaman herbal komersial yang akarnya dilaporkan berkhasiat sebagai obat afrodisiak, diuretik, dan tonik. Penelitian ini bertujuan untuk mengevaluasi pengaruh ekstrak purwoceng terhadap perkembangan testis ikan lele Clarias sp. yang meliputi peningkatan bobot testis, nilai GSI, serta nilai spermatokrit. Perlakuan terdiri atas pemberian ekstrak purwoceng melalui pakan dengan dosis 0; 2,5; 5 dan 7,5 g/kg pakan. Adapun ikan yang diujicobakan pada penelitian adalah ikan lele jantan dengan bobot awal 200–300 g dan padat tebar 10 ekor/bak. Pemeliharaan ikan dilakukan pada bak berukuran 2×1,5×1 m3 yang diisi air dengan ketinggian  60–70 cm. Hasil percobaan menunjukkan bahwa pemberian ekstrak purwoceng dengan dosis 5 g/kg yang dicampur dalam pakan meningkatkan nilai bobot testis, nilai GSI dan kadar spermatokrit  pada lele jantan dewasa. Kata kunci: ekstrak purwoceng, spermatogenesis, ikan lele

  18. Effect of pubertal nano-TiO2 exposure on testosterone synthesis and spermatogenesis in mice.

    Science.gov (United States)

    Jia, Fang; Sun, Zilong; Yan, Xiaoyan; Zhou, Bingrui; Wang, Jundong

    2014-03-01

    Titanium dioxide nanoparticles (nano-TiO2) are frequently used in cosmetics, paints, sunscreens and the like. Recent studies have demonstrated that nano-TiO2 might be deleterious for the male reproductive function. However, the effects of pubertal nano-TiO2 exposure on testosterone (T) synthesis and spermatogenesis remained to be elucidated. Here, we investigated the effect of pubertal nano-TiO2 exposure on the synthesis of T and spermatogenesis. Nano-TiO2 was orally administered daily to Kunming male mice from 28th postnatal day (PND 28) to PND 70. The percentage of spermatozoa abnormality in epididymides was markedly increased in mice exposed to nano-TiO2; decreased layers of spermatogenic cells and vacuoles in seminiferous tubules were also observed in the nano-TiO2 treated group. In addition, pubertal nano-TiO2 exposure significantly decreased the serum T levels in male mice. Moreover, mice exposures to nano-TiO2 significantly reduced the expression of 17β-hydroxysteroid dehydrogenase and P450 17α-hydroxysteroid dehydrogenase in the testis of mice, while the expression of cytochrome P450-19, a key enzyme for the translation of T to estradiol (E2), was increased. Taken together, these results indicated that nano-TiO2 could influence the levels of serum T through changes in both the synthesis and translation of T. Furthermore, the decreased serum T synthesis might contribute to the reduced spermatogenesis in mice exposed to nano-TiO2.

  19. Methamidophos alters sperm function and DNA at different stages of spermatogenesis in mice

    Energy Technology Data Exchange (ETDEWEB)

    Urióstegui-Acosta, Mayrut; Hernández-Ochoa, Isabel [Departamento de Toxicología, CINVESTAV-IPN, D.F. (Mexico); Sánchez-Gutiérrez, Manuel [Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Hidalgo (Mexico); Piña-Guzmán, Belem [Instituto Politécnico Nacional-UPIBI, D.F. (Mexico); Rafael-Vázquez, Leticia; Solís-Heredia, M.J.; Martínez-Aguilar, Gerardo [Departamento de Toxicología, CINVESTAV-IPN, D.F. (Mexico); Quintanilla-Vega, Betzabet, E-mail: mquintan@cinvestav.mx [Departamento de Toxicología, CINVESTAV-IPN, D.F. (Mexico)

    2014-09-15

    Methamidophos (MET) is a highly toxic organophosphate (OP) pesticide that is widely used in developing countries. MET has male reproductive effects, including decreased fertility. We evaluated MET effects on sperm quality, fertilization and DNA integrity, exploring the sensitivity of different stages of spermatogenesis. Adult male mice received MET (3.75 or 5 mg/kg-bw/ip/day/4 days) and were euthanized 1, 28 or 45 days post-treatment (dpt) to evaluate MET's effects on epididymal maturation, meiosis or mitosis, respectively. Spermatozoa were obtained from the cauda epididymis–vas deferens and were evaluated for sperm quality, acrosome reaction (AR; Coomassie staining), mitochondrial membrane potential (by JC-1), DNA damage (comet assay), oxidative damage (malondialdehyde (MDA) production), in vitro fertilization and protein phosphorylation (immunodetection), and erythrocyte acetylcholinesterase (AChE) activity. At 1-dpt, MET inhibited AChE (43–57%) and increased abnormal cells (6%). While at 28- and 45-dpt, sperm motility and viability were significantly reduced with an increasing MET dose, and abnormal morphology increased at 5 mg/kg/day/4 days. MDA and mitochondrial activity were not affected at any dose or time. DNA damage (OTM and %DNA) was observed at 5 mg/kg/day/4 days in a time-dependent manner, whereas both parameters were altered in cells from mice exposed to 3.75 mg/kg/day/4 days only at 28-dpt. Depending on the time of collection, initial-, spontaneous- and induced-AR were altered at 5 mg/kg/day/4 days, and the fertilization capacity also decreased. Sperm phosphorylation (at serine and tyrosine residues) was observed at all time points. Data suggest that meiosis and mitosis are the more sensitive stages of spermatogenesis for MET reproductive toxicity compared to epididymal maturation. - Highlights: • Methamidophos alters sperm cell function at different stages of spermatogenesis. • Testicular stages of spermatogenesis are more sensitive to

  20. Y chromosome microdeletions and alterations of spermatogenesis, patient approach and genetic counseling.

    Science.gov (United States)

    Rives, Nathalie

    2014-05-01

    Infertility affects 15% of couples at reproductive age and human male infertility appears frequently idiopathic. The main genetic causes of spermatogenesis defect responsible for non-obstructive azoospermia and severe oligozoospermia are constitutional chromosomal abnormalities and microdeletions in the azoospermia factor region of the Y chromosome. The improvement of the Yq microdeletion screening method gave new insights in the mechanism responsible for the genesis of Yq microdeletions and for the consequences of the management of male infertility and genetic counselling in case of assisted reproductive technology. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  1. Overview of the Autonomic Nervous System

    Science.gov (United States)

    ... be reversible or progressive. Anatomy of the autonomic nervous system The autonomic nervous system is the part of ... organs they connect with. Function of the autonomic nervous system The autonomic nervous system controls internal body processes ...

  2. Autonomous Forest Fire Detection

    NARCIS (Netherlands)

    Breejen, E. den; Breuers, M.; Cremer, F.; Kemp, R.A.W.; Roos, M.; Schutte, K.; Vries, J.S. de

    1998-01-01

    Forest fire detection is a very important issue in the pre-suppression process. Timely detection allows the suppression units to reach the fire in its initial stages and this will reduce the suppression costs considerably. The autonomous forest fire detection principle is based on temporal contrast

  3. Towards autonomous vehicles.

    Science.gov (United States)

    2013-11-01

    We are moving towards an age of autonomous vehicles. Cycles of innovation initiated in the public and private sectors : have led one into another since the 1990s; and out of these efforts have sprung a variety of Advanced Driver Assistance : Systems ...

  4. Experimental Autonomous Vehicle Systems

    DEFF Research Database (Denmark)

    Ravn, Ole; Andersen, Nils Axel

    1998-01-01

    The paper describes the requirements for and a prototype configuration of a software architecture for control of an experimental autonomous vehicle. The test bed nature of the system is emphasised in the choice of architecture making re-configurability, data logging and extendability simple...

  5. ADAM: ADaptive Autonomous Machine

    NARCIS (Netherlands)

    van Oosten, Daan C.; Nijenhuis, Lucas F.J.; Bakkers, André; Vervoort, Wiek

    1996-01-01

    This paper describes a part of the development of an adaptive autonomous machine that is able to move in an unknown world extract knowledge out of the perceived data, has the possibility to reason, and finally has the capability to exchange experiences and knowledge with other agents. The agent is

  6. Detrimental effects of prenatal exposure to filtered diesel exhaust on mouse spermatogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Naoka; Niwata, Yuichiro; Takeda, Ken [Tokyo University of Science, Department of Hygiene Chemistry, Faculty of Pharmaceutical Sciences, Chiba (Japan); Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), Saitama (Japan); Oshio, Shigeru [Tokyo University of Science, Department of Hygiene Chemistry, Faculty of Pharmaceutical Sciences, Chiba (Japan); Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), Saitama (Japan); Ohu University, Department of Hygiene Chemistry, School of Pharmaceutical Sciences, Fukushima (Japan); Ohu University, Department of Hygiene Chemistry, School of Pharmaceutical Sciences, Koriyama, Fukushima (Japan); Yoshida, Seiichi [Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), Saitama (Japan); Oita University of Nursing and Health Sciences, Department of Health and Sciences, Oita (Japan); Tsukue, Naomi [Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), Saitama (Japan); Sugawara, Isamu [Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), Saitama (Japan); The Research Institute of Tuberculosis, Mycobacterial Reference Center, Tokyo (Japan); Takano, Hirohisa [Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), Saitama (Japan); National Institute for Environmental Studies, Environmental Health Sciences Division, Ibaraki (Japan)

    2008-11-15

    We recently showed that prenatal exposure to diesel exhaust (DE) disrupts spermatogenesis in mouse offspring. This study was undertaken to determine whether filtered DE in which 99.97% of diesel exhaust particles >0.3{mu}m in diameter were removed affects spermatogenesis in growing mice. After prenatal exposure to filtered DE for 2-16 days postcoitum, we examined daily sperm production (DSP), testicular histology, serum testosterone levels and mRNA expression of hormone synthesis process-related factors. In the filtered DE exposed group, DSP was markedly reduced at 12 weeks compared with the control group; clean air exposed group. Histological examination showed multinucleated giant cells and partial vacuolation in the seminiferous tubules of the exposed group. Testosterone was elevated significantly at 5 weeks. Moreover, luteinizing hormone receptor mRNA at 5 and 12 weeks, 17{alpha}-hydroxylase/C17-20-lyase and 17{beta}-hydroxysteroid dehydrogenase mRNAs at 12 weeks were significantly elevated. These results suggest that filtered DE retains its toxic effects on the male reproductive system following prenatal exposure. (orig.)

  7. The endocytic recycling regulator EHD1 is essential for spermatogenesis and male fertility in mice

    Directory of Open Access Journals (Sweden)

    Hess Rex A

    2010-04-01

    Full Text Available Abstract Background The C-terminal Eps15 homology domain-containing protein 1 (EHD1 is ubiquitously expressed and regulates the endocytic trafficking and recycling of membrane components and several transmembrane receptors. To elucidate the function of EHD1 in mammalian development, we generated Ehd1-/- mice using a Cre/loxP system. Results Both male and female Ehd1-/- mice survived at sub-Mendelian ratios. A proportion of Ehd1-/- mice were viable and showed smaller size at birth, which continued into adulthood. Ehd1-/- adult males were infertile and displayed decreased testis size, whereas Ehd1-/- females were fertile. In situ hybridization and immunohistochemistry of developing wildtype mouse testes revealed EHD1 expression in most cells of the seminiferous epithelia. Histopathology revealed abnormal spermatogenesis in the seminiferous tubules and the absence of mature spermatozoa in the epididymides of Ehd1-/- males. Seminiferous tubules showed disruption of the normal spermatogenic cycle with abnormal acrosomal development on round spermatids, clumping of acrosomes, misaligned spermatids and the absence of normal elongated spermatids in Ehd1-/- males. Light and electron microscopy analyses indicated that elongated spermatids were abnormally phagocytosed by Sertoli cells in Ehd1-/- mice. Conclusions Contrary to a previous report, these results demonstrate an important role for EHD1 in pre- and post-natal development with a specific role in spermatogenesis.

  8. A study on the effect of thiotepa on mice spermatogenesis using light and electronic microscope.

    Science.gov (United States)

    Nejad, D M; Rad, J S; Roshankar, L; Karimipor, M; Ghanbari, A A; Aazami, A; Valilou, M R

    2008-08-01

    The present study was designed to explore the spermatogenic effect of intraperitoneal administration of thiotepa in mice. It is known the chemotherapy could affect testicular function and result in infertility. There are few reports on the side effect of thiotepa on spermatogenesis when are used as anticancer drug. Therefore, in the present study the effect of thiotepa on spermatogenesis was evaluated by electron microscopy. A total of 20 balb/c mice were used in this study. They were divided into control and thiotepa treated groups. Thiotepa was administrated as 2.5 mg kg(-1) for 5 days. The mice were sacrificed after 5 weeks and testicular specimens were removed, fixed in boueins fixative and 2.5% Glutaraldehide then prepared for light and electron microscopic study. Light microscopy showed that the thickness of germinal epithelium was decreased in thiotepa treated group and many seminiferous tubules have lost germinal cells. Electron microscopy revealed that in experimental group several intercellular spaces appeared between spermatogonial and sertoli cells. The basement membrane became irregular and intercellular vacuoles were present in sertoli and spermatogonial cells. Nuclear chromatin was condensed and there were several vacuolated mitochondria. It was indicated that thiotepa affected testicular germinal epithelium by both cytotoxic effect and induction of apoptosis.

  9. The effect of chronic administration of ketoconazol on spermatogenesis indices and testis tissue in mice

    Directory of Open Access Journals (Sweden)

    S.E Safavi

    2009-02-01

    Full Text Available Ketoconazole, a broad spectrum antifungal agent has been employed widely in the treatment of fungal diseases. In addition to being antifungal, studies have indicated that this drug has an inhibitory effect on steroid hormone production including glucocorticoids and sex hormones and also its administration causes reduction in the amount of blood testosterone level and histologic changes in testicular tissue of laboratory animals. The aim of this study is to determine the effect of long term ketoconazole administration on spermatogenesis indices in testicular tissue of mice. In this experimental study 50 male mice were used which were allocated to 5 groups each containing 10 animals. The mice received a 50 mg/kg dose of ketoconazole daily for a period of 15 days, 1, 2 and 3 months orally. One group was used as the control and the other 4 groups received Ketoconazole, testicular tissue samples were collected at the end of the aforementioned time period, and after preparation of tissue sections and staining with hematoxylin and coin the spermiogenesis indices including tubular differentiation index (TDI, spermatogenesis index (SI and repopulation index (RI were studied. The results indicated that SI and RI decreased significantly (p

  10. Quantitative aspects of spermatogenesis in rats and dogs after repeated hexachlorophene treatment.

    Science.gov (United States)

    James, R W; Heywood, R; Crook, D

    1980-05-01

    Hexachlorophene was administered orally, at subneurotoxic doses, to rats (5 mg/kg/day) and dogs (3 mg/kg/day) for 9 weeks: some of the rats and dogs were observed for a further 13 weeks. The serum concentrations of pituitary gonadotrophin and testosterone were unaffected in either species. No changes were induced in the testicular dimensions or semen characteristics of dogs and no macroscopic post mortem abnormalities, organ weight differences or lesions detectable by conventional light microscopy were found in their testes, pituitaries or secondary sex organs. A transient reduction in the number of germ cells counted in cross-sections of seminiferous tubules was seen in rats after 4 weeks treatment. After 9 weeks treatment, reduced spermatogonial counts were recorded in canine seminiferous tubules; in other respects spermatogenesis was proceeding normally. No delayed effects were apparent in eith species. It is concluded that repeated administration of hexachlorophene at subneurotoxic levels did not induce significant impairment of spermatogenesis in rats or dogs.

  11. Confocal Analysis of Nuclear Lamina Behavior during Male Meiosis and Spermatogenesis in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Fabiana Fabbretti

    Full Text Available Lamin family proteins are structural components of a filamentous framework, the nuclear lamina (NL, underlying the inner membrane of nuclear envelope. The NL not only plays a role in nucleus mechanical support and nuclear shaping, but is also involved in many cellular processes including DNA replication, gene expression and chromatin positioning. Spermatogenesis is a very complex differentiation process in which each stage is characterized by nuclear architecture dramatic changes, from the early mitotic stage to the sperm differentiation final stage. Nevertheless, very few data are present in the literature on the NL behavior during this process. Here we show the first and complete description of NL behavior during meiosis and spermatogenesis in Drosophila melanogaster. By confocal imaging, we characterized the NL modifications from mitotic stages, through meiotic divisions to sperm differentiation with an anti-laminDm0 antibody against the major component of the Drosophila NL. We observed that continuous changes in the NL structure occurred in parallel with chromatin reorganization throughout the whole process and that meiotic divisions occurred in a closed context. Finally, we analyzed NL in solofuso meiotic mutant, where chromatin segregation is severely affected, and found the strict correlation between the presence of chromatin and that of NL.

  12. Putting things in place for fertilization: discovering roles for importin proteins in cell fate and spermatogenesis

    Directory of Open Access Journals (Sweden)

    Kate L. Loveland

    2015-01-01

    Full Text Available Importin proteins were originally characterized for their central role in protein transport through the nuclear pores, the only intracellular entry to the nucleus. This vital function must be tightly regulated to control access by transcription factors and other nuclear proteins to genomic DNA, to achieve appropriate modulation of cellular behaviors affecting cell fate. Importin-mediated nucleocytoplasmic transport relies on their specific recognition of cargoes, with each importin binding to distinct and overlapping protein subsets. Knowledge of importin function has expanded substantially in regard to three key developmental systems: embryonic stem cells, muscle cells and the germ line. In the decade since the potential for regulated nucleocytoplasmic transport to contribute to spermatogenesis was proposed, we and others have shown that the importins that ferry transcription factors into the nucleus perform additional roles, which control cell fate. This review presents key findings from studies of mammalian spermatogenesis that reveal potential new pathways by which male fertility and infertility arise. These studies of germline genesis illuminate new ways in which importin proteins govern cellular differentiation, including via directing proteins to distinct intracellular compartments and by determining cellular stress responses.

  13. Effects of aqueous extract of celery (Apium graveolens L.) leaves on spermatogenesis in healthy male rats.

    Science.gov (United States)

    Hardani, Ameneh; Afzalzadeh, Mohammad Reza; Amirzargar, Ashraf; Mansouri, Esrafil; Meamar, Zakieh

    2015-01-01

    Nowadays, a lot of attention has been paid to the therapeutic properties of herbs, including evaluation of the effects of these plants on fertility in laboratory animals. Apium graveolens L. (celery) has been widely used in traditional medicine for treatment of various disorders including impotency. Therefore, this study was designed to investigate the effects of aqueous extract of A. graveolens on testicular tissue and spermatogenesis in healthy male rats. In this research, 24 apparently healthy male rats were divided into three groups, including eight rats in each. The first group as control received only distilled water 1 ml/animal/day. The second and third groups orally received 100 and 200 mg/kg b.w. of the extract, respectively, for 30 days. The day after the last administration of the extract, the rats were sacrificed, the testes were removed entirely, and the morphometric studies were carried out. Epididymal sperm count and histological studies of testicular tissue were conducted. The comparison between the treated and control groups revealed a remarkable increase in the seminiferous tubules diameter, testes volume (p≤0.001), and the number of spermatogonia, primary spermatocytes and spermatozoa. Furthermore, the increase in the number of spermatids and epididymal weight were only significant at high doses of the extract (p≤ 0.05). The results from this study indicated that administration of celery leaf extract may improve spermatogenesis process and also be useful for some sperm fertility parameters.

  14. Effects of aqueous extract of celery (Apium graveolens L. leaves on spermatogenesis in healthy male rats

    Directory of Open Access Journals (Sweden)

    Ameneh Hardani

    2015-02-01

    Full Text Available Objectives: Nowadays, a lot of attention has been paid to the therapeutic properties of herbs, including evaluation of the effects of these plants on fertility in laboratory animals. Apium graveolens L. (celery has been widely used in traditional medicine for treatment of various disorders including impotency. Therefore, this study was designed to investigate the effects of aqueous extract of A. graveolens on testicular tissue and spermatogenesis in healthy male rats. Materials and Methods: In this research, 24 apparently healthy male rats were divided into three groups, including eight rats in each. The first group as control received only distilled water 1 ml/animal/day. The second and third groups orally received 100 and 200 mg/kg b.w. of the extract, respectively, for 30 days. The day after the last administration of the extract, the rats were sacrificed, the testes were removed entirely, and the morphometric studies were carried out. Epididymal sperm count and histological studies of testicular tissue were conducted. Results: The comparison between the treated and control groups revealed a remarkable increase in the seminiferous tubules diameter, testes volume (p≤0.001, and the number of spermatogonia, primary spermatocytes and spermatozoa. Furthermore, the increase in the number of spermatids and epididymal weight were only significant at high doses of the extract (p≤ 0.05. Conclusions: The results from this study indicated that administration of celery leaf extract may improve spermatogenesis process and also be useful for some sperm fertility parameters.

  15. Concomitant intramuscular human chorionic gonadotropin preserves spermatogenesis in men undergoing testosterone replacement therapy.

    Science.gov (United States)

    Hsieh, Tung-Chin; Pastuszak, Alexander W; Hwang, Kathleen; Lipshultz, Larry I

    2013-02-01

    Testosterone replacement therapy results in decreased serum gonadotropins and intratesticular testosterone, and impairs spermatogenesis, leading to azoospermia in 40% of patients. However, intratesticular testosterone can be maintained during testosterone replacement therapy with co-administration of low dose human chorionic gonadotropin, which may support continued spermatogenesis in patients on testosterone replacement therapy. We retrospectively reviewed the records of hypogonadal men treated with testosterone replacement therapy and concomitant low dose human chorionic gonadotropin. Testosterone replacement consisted of daily topical gel or weekly intramuscular injection with intramuscular human chorionic gonadotropin (500 IU) every other day. Serum and free testosterone, estradiol, semen parameters and pregnancy rates were evaluated before and during therapy. A total of 26 men with a mean age of 35.9 years were included in the study. Mean followup was 6.2 months. Of the men 19 were treated with injectable testosterone and 7 were treated with transdermal gel. Mean serum hormone levels before vs during treatment were testosterone 207.2 vs 1,055.5 ng/dl (p human chorionic gonadotropin therapy. Nine of 26 men contributed to pregnancy with the partner during followup. Low dose human chorionic gonadotropin appears to maintain semen parameters in hypogonadal men on testosterone replacement therapy. Concurrent testosterone replacement and human chorionic gonadotropin use may preserve fertility in hypogonadal males who desire fertility preservation while on testosterone replacement therapy. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. Nucleolar-persistence phenomenon during spermatogenesis in genus Meccus (Hemiptera, Triatominae).

    Science.gov (United States)

    Madeira, F F; Lima, A A C; Rosa, J A; Azeredo-Oliveira, M T V; Alevi, K C C

    2016-03-28

    The Triatominae subfamily consists of 150 species in 18 genera, grouped into six tribes. In cytogenetics, triatomines are important biological models because they have holocentric chromosomes and nucleolar persistence in meiosis. The phenomenon of nucleolar persistence has been described for 23 species of triatomine in three genera: Triatoma, Rhodnius, and Panstrongylus. However, new species and genera should be analyzed to assess whether nucleolar persistence is a peculiarity of Triatominae. Thus, this study aimed to analyze nucleolar behavior during spermatogenesis of Meccus pallidipennis and M. longipennis, focusing on the nucleolar-persistence phenomenon. Through the analysis of spermatogenesis, more specifically of meiotic metaphase, we observed the phenomenon of nucleolar persistence in M. pallidipennis and M. longipennis, represented by remnants of nucleolar material in metaphase. Thus, although nucleologenesis of new species, and, especially, new genera, should be analyzed, this study confirms for the first time the phenomenon of nucleolar persistence in the genus Meccus. Therefore, we emphasize the importance of new studies in this area in order to assess whether this phenomenon is truly a synapomorphy of these hematophagous insects.

  17. Dietary intake of high-dose biotin inhibits spermatogenesis in young rats.

    Science.gov (United States)

    Sawamura, Hiromi; Ikeda, Chieko; Shimada, Ryoko; Yoshii, Yui; Watanabe, Toshiaki

    2015-02-01

    To characterize a new function of the water-soluble vitamin, biotin, in reproduction and early growth in mammals, the effects of high dietary doses of biotin on early spermatogenesis were biochemically and histologically investigated in male rats. Weaned rats were fed a CE-2 (control) diet containing 0.00004% biotin, or a control diet supplemented with 0.01%, 0.1%, or 1.0% biotin. Pair-fed rats were fed a control diet that was equal in calories to the amount ingested by the 1.0% biotin group, because food intake was decreased in the 1.0% biotin group. Food intake and body weight gain were lower in the 1.0% biotin group than in the control group. The kidney, brain and testis weights were significantly lower in the 1.0% biotin group than in the pair-fed group after 6 weeks of feeding. The accumulation of biotin in the liver and testis increased in a dose-dependent manner. In the 1.0% biotin group, the number of mature sperm was markedly lower, that of sperm with morphologically abnormal heads, mainly consisting of round heads, had increased. In addition, the development of seminiferous tubules was inhibited, and few spermatogonia and no spermatocytes were histologically observed. These results demonstrated that the long-term intake of high-dose biotin inhibited spermatogenesis in young male rats. © 2014 Japanese Teratology Society.

  18. Experimental testicular tissue banking to generate spermatogenesis in the future: A multidisciplinary team approach.

    Science.gov (United States)

    Sadri-Ardekani, Hooman; McLean, Thomas W; Kogan, Stanley; Sirintrapun, Joseph; Crowell, Kathryn; Yousif, Mustafa Q; Hodges, Steve J; Petty, John; Pranikoff, Thomas; Sieren, Leah; Zeller, Kristen; Atala, Anthony

    2016-04-15

    Spermatogonial stem cell (SSC) loss due to cancer treatment, developmental disorder or genetic abnormality may cause permanent infertility. Cryopreservation of ejaculated sperm is an effective method of fertility preservation in adult males at risk of infertility. However this is not an option in pre-pubertal boys because spermatogenesis has not yet started, and it is difficult in adolescents who are not sexually mature. Therefore testicular tissue cryopreservation to preserve SSCs for future generation of spermatogenesis, either in vivo or in vitro, could be an option for these groups of patients. Although SSC transplantation has been successful in several species including non-human primates, it is still experimental in humans. There are several remaining concerns which need to be addressed before initiating trials of human SSC autotransplantation. Establishment of a testicular tissue banking system is a fundamental step towards using SSC technology as a fertility preservation method. It is important to understand the consultation, harvesting the testicular tissue, histological evaluation, cryopreservation, and long term storage aspects. We describe here a multidisciplinary approach to establish testicular tissue banking for males at risk of infertility. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Study of Spermatogenesis in Wistar Adult Rats Administrated to Long Term of Ruta Graveolens

    Directory of Open Access Journals (Sweden)

    Bazrafkan

    2014-07-01

    Full Text Available Background In Iranian folk medicine Ruta graveolens has been used for female and male contraceptive. There are few studies about the effect of this plant on spermatogenesis. Objectives In this study the effect of long term administration of aqueous extract of RG on spermatogenesis has been investigated. Materials and Methods Animals were allocated into 1 control: which did not receive anything, 2 vehicle which received only normal saline and 3 experiment: which received Ruta extract (300 mg/kg administered by gavage once a day for 100 days. A day after last gavage all the individuals were killed by euthanasia. The right testes and epididymis were extruded. The sperm motility was assessed and classified as progressive, no progressive. Results There was a significant decrease in the number of spermatogonia (P 0.05.The fertilization capacity of sperm of rats in experimental group was significantly lower than other groups (P > 0.05. Conclusions It is concluded that the aqueous extract of Ruta graveolens diminishes the reproductive system activity and might be a useful substance for birth control process.

  20. Genetic and epigenetic mechanisms of regulation, chronology and dynamics of spermatogenesis of mammals

    Directory of Open Access Journals (Sweden)

    L. F. Kurilo

    2015-01-01

    Full Text Available Genetic and epigenetic mechanisms of spermatogenesis – long process with many stages regulation are discussed. DNA code is the entirety of hereditary information, epigenetic mechanisms of gene regulation act without altering primary nucleotide sequences. Epigenetic regulation is a complex process, in which components of different groups of epigenetic modifications (non-coding RNAs, DNA methylation and histone modification work together. Mistakes in any of the components of the process may cause impaired spermatogenesis and/or infertility, and may cause epigenetic diseases. Nowadays 90 imprinted genes and loci on 13 chromosomes are revealed. More then 10 human diseases involving genomic imprinting are known (Angelman syndrome, Prader–Willi syndrome, Russell–Silver syndrome, Beckwith–Wiedemann syndrome etc.. DNA methylation is essential for normal development and is associated with a number of key processes including animal growth and development, transcription, DNA replication and reparation, cell differentiation, genomic imprinting, X-chromosome inactivation, suppression of repetitive elements and carcinogenesis. 

  1. Repression of hspA2 messenger RNA in human testes with abnormal spermatogenesis.

    Science.gov (United States)

    Son, W Y; Han, C T; Hwang, S H; Lee, J H; Kim, S; Kim, Y C

    2000-06-01

    To evaluate the messenger RNA (mRNA) expression of hspA2 in testes of infertile men with azoospermia. Prospective study. Center for Reproduction and Genetics, Pundang Je-Saeng General Hospital, Dae-Jin Medical Center, Korea. Azoospermic patients (n = 15) undergoing testicular biopsy for pathologic evaluation were selected. After pathologic evaluation, testicular biopsy specimens were subdivided into three groups: group 1, normal spermatogenesis (n = 5); group 2, spermatocyte arrest (n = 5); and group 3, Sertoli cell-only syndrome (n = 5). The levels of hspA2 mRNA expression were compared in testes of group 1, group 2, and group 3 with the use of a competitive reverse transcription polymerase chain reaction (RT-PCR) technique. Comparison of hspA2 mRNA levels in testes. On competitive RT-PCR analyses for hspA2 mRNA, significant hspA2 expression was observed in group 1, whereas a very low level of hspA2 was expressed in groups 2 and 3. This study demonstrates that hspA2 gene expression is down-regulated in human testes with abnormal spermatogenesis, which in turn suggests that the hspA2 gene might play a specific role during meiosis in human testes.

  2. Functional Imaging of Autonomic Regulation: Methods and Key Findings

    Directory of Open Access Journals (Sweden)

    Paul M Macey

    2016-01-01

    Full Text Available Central nervous system processing of autonomic function involves a network of regions throughout the brain which can be visualized and measured with neuroimaging techniques, notably functional magnetic resonance imaging (fMRI. The development of fMRI procedures has both confirmed and extended earlier findings from animal models, and human stroke and lesion studies. Assessments with fMRI can elucidate interactions between different central sites in regulating normal autonomic patterning, and demonstrate how disturbed systems can interact to produce aberrant regulation during autonomic challenges. Understanding autonomic dysfunction in various illnesses reveals mechanisms that potentially lead to interventions in the impairments. The objectives here are to: 1 describe the fMRI neuroimaging methodology for assessment of autonomic neural control, 2 outline the widespread, lateralized distribution of function in autonomic sites in the normal brain which includes structures from the neocortex through the medulla and cerebellum, 3 illustrate the importance of the time course of neural changes when coordinating responses, and how those patterns are impacted in conditions of sleep-disordered breathing, and 4 highlight opportunities for future research studies with emerging methodologies. Methodological considerations specific to autonomic testing include timing of challenges relative to the underlying fMRI signal, spatial resolution sufficient to identify autonomic brainstem nuclei, blood pressure and blood oxygenation influences on the fMRI signal, and the sustained timing, often measured in minutes of challenge periods and recovery. Key findings include the lateralized nature of autonomic organization, which is reminiscent of asymmetric motor, sensory and language pathways. Testing brain function during autonomic challenges demonstrate closely-integrated timing of responses in connected brain areas during autonomic challenges, and the involvement with

  3. Autonomous Robot Retrieval System

    OpenAIRE

    Ahern, S.

    2015-01-01

    Mobile robots are increasingly being deployed in environments hazardous to humans. However, many of these robots require remote control operation or are tethered, requiring the human operator to remain within a potentially hazardous radius of the area of operation. To resolve this issue an Autonomous Robot Retrieval System (ARRS) utilising Open RatSLAM based on the Lego NXT 2.0 robotics platform is proposed but could not be implemented due to memory limitations of the hardware. An occupancy g...

  4. Demasculinisation of sexually mature male common carp, Cyprinus carpio, exposed to 4-tert-pentylphenol during spermatogenesis

    NARCIS (Netherlands)

    Gimeno, S.; Komen, H.; Jobling, S.; Sumpter, J.; Bowmer, T.

    1998-01-01

    Sexually mature male common carp (Cyprinus carpio) were exposed for a 3-month period to sublethal concentrations of 4-tert-pentylphenol (TPP) and to 17β-estradiol (E2) during spermatogenesis. This was part of a broad research programme investigating the effects of TPP on the life stages of the carp

  5. Effect of Ruta graveolens and Cannabis sativa alcoholic extract on spermatogenesis in the adult wistar male rats

    Directory of Open Access Journals (Sweden)

    M R Sailani

    2007-01-01

    Full Text Available Objective: The present study was undertaken to evaluate the effects of alcohol extracts of Ruta graveolens and Cannabis sativa that were used traditionally in medieval Persian medicine as male contraceptive drugs, on spermatogenesis in the adult male rats. Materials and Methods: Ethanol extracts of these plants were obtained by the maceration method. The male rats were injected intraperitionaly with C. sativa and R. graveolens 5% ethanol extracts at dose of 20 mg/day for 20 consecutive days, respectively. Twenty-four hours after the last treatment, testicular function was assessed by epididymal sperm count. Result: The statistical results showed that the ethanol extracts of these plants reduced the number of sperms significantly ( P =0.00 in the treatment groups in comparison to the control group. The results also showed that the group, treated by extract of R. graveolens reduced spermatogenesis more than the group treated by extracts of C. sativa . Conclusion: The present study demonstrated the spermatogenesis reducing properties of the ethanol extracts of R. graveolens and C. sativa in the adult male wistar rats but more studies are necessary to reveal the mechanism of action that is involved in spermatogenesis.

  6. Nature's Autonomous Oscillators

    Science.gov (United States)

    Mayr, H. G.; Yee, J.-H.; Mayr, M.; Schnetzler, R.

    2012-01-01

    Nonlinearity is required to produce autonomous oscillations without external time dependent source, and an example is the pendulum clock. The escapement mechanism of the clock imparts an impulse for each swing direction, which keeps the pendulum oscillating at the resonance frequency. Among nature's observed autonomous oscillators, examples are the quasi-biennial oscillation and bimonthly oscillation of the Earth atmosphere, and the 22-year solar oscillation. The oscillations have been simulated in numerical models without external time dependent source, and in Section 2 we summarize the results. Specifically, we shall discuss the nonlinearities that are involved in generating the oscillations, and the processes that produce the periodicities. In biology, insects have flight muscles, which function autonomously with wing frequencies that far exceed the animals' neural capacity; Stretch-activation of muscle contraction is the mechanism that produces the high frequency oscillation of insect flight, discussed in Section 3. The same mechanism is also invoked to explain the functioning of the cardiac muscle. In Section 4, we present a tutorial review of the cardio-vascular system, heart anatomy, and muscle cell physiology, leading up to Starling's Law of the Heart, which supports our notion that the human heart is also a nonlinear oscillator. In Section 5, we offer a broad perspective of the tenuous links between the fluid dynamical oscillators and the human heart physiology.

  7. Testicular dysgenesis syndrome comprises some but not all cases of hypospadias and impaired spermatogenesis

    DEFF Research Database (Denmark)

    Jørgensen, N; Rajpert-De Meyts, Ewa; Main, K M

    2010-01-01

    are most likely caused by TDS. However, the frequency of the syndrome in the general population and to what extent poor semen quality and hypospadias are actually biologically related through a foetal mechanism remain unresolved. Hypospadias and impaired spermatogenesis can be classified as TDS if combined...... with cryptorchidism or TGCC. By contrast, recent studies demonstrated that among men with isolated hypospadias, only a fraction of cases are linked to TDS. There is no doubt that TDS contributes to impaired semen quality. This is most obvious for cases with visible dysgenetic features in testis histology......, but in the majority of men with impaired semen quality as the only symptom, an association with TDS is less clear. Such cases have a very heterogeneous aetiology and may be caused by a host of other - often post-natal-factors. In conclusion, the TDS as a holistic concept has inspired new research activities and led...

  8. Patterns of mutational sensitivity to chemicals in poststem-cell stages of mouse spermatogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Russell, L.B.

    1989-01-01

    For a given spermatozoon participating in conception, only a relatively short period of its cell lineage has been spent in poststem-cell stages of spermatogenesis. For this reason, the male genome participating in formation of the conceptus is less likely to have been exposed to mutagens during poststem-cell stages than during spermatogonial stem-cell of earlier stages. Nevertheless, in addressing questions of genetic hazard, the later stages cannot be ignored and may even represent a significant part of the risk if, as is already known for some mutagens, these cell types are disproportionally sensitive. Furthermore, the poststem-cell stages, which vary considerably amongst themselves in their array of chromosome and chromatin configurations, offer biological materials that are potentially useful in addressing questions of mutagenic mechanisms. 22 refs., 4 tabs.

  9. Effect of temperature on the concentration of plasma gonadotropine and spermatogenesis of the goldfish Carassius auratus

    Energy Technology Data Exchange (ETDEWEB)

    Gillet, C.; Billard, R.; Breton, B.

    1977-01-01

    Concentrations of immunoreactive plasma gonadotropin (c-GtH) were measured for goldfish kept at conditions of temperature held constant or increasing between 10 and 30/sup 0/C, between February and July. At temperatures of 17/sup 0/C or above the levels of plasma c-GtH were significantly (P < 0.005) higher during April and May than at 10/sup 0/C. In April the pituitary concentration of c-GtH was maximum for fish held at 17/sup 0/C or above and the minimum for fish held below 17/sup 0/C, but in June the situation was reversed. A study of the gonads showed that spermatogenesis is faster at 17--24/sup 0/C than at 10/sup 0/C, but at 30/sup 0/C spermatogenic activity was inhibited.

  10. Data on spermatogenesis in rat males gestationally exposed to bisphenol A and high fat diets

    Directory of Open Access Journals (Sweden)

    Pheruza Tarapore

    2016-12-01

    Full Text Available This data article contains supporting information regarding the research article entitled “High butter-fat diet and bisphenol A additively impair male rat spermatogenesis” (P. Tarapore, M. Hennessy, D. Song, J. Ying, B. Ouyang, V. Govindarajah, et al., [1]. Sprague–Dawley females were fed AIN, high fat butter, 17α-ethinyl estradiol, or high fat butter plus four bisphenol A doses (2500 µg/kg bw-d, 250 µg/kg bw-d, 25 µg/kg bw-d, and 2.5 µg/kg bw-d before and during pregnancy. All diets were switched to AIN after the pups were born. Male offspring received testosterone (T- and estradiol-17β (E2-filled implants from postnatal day 70–210 for 20 weeks (T+E2 rat model. The testes were weighed, and examined for impairments in spermatogenesis.

  11. The morphology of the male reproductive system, spermatogenesis and the spermatozoon of Daphnia magna (Crustacea: Branchiopoda).

    Science.gov (United States)

    Wuerz, Maggie; Huebner, Erwin; Huebner, Judith

    2017-11-01

    This study analyses the histological and cellular morphology of the testis and sperm development in the male Daphnia magna Straus 1820. Due to the rarity of males and predominately parthenogenetic lifecycle of Daphnia, there has been limited detailed information on males in contrast to the well-studied female. Using light and electron microscopy approaches, we describe the morphology of the testis during the progression from an immature to mature testis. The testis has an encasing muscular mesh sheath outside the basal lamina, beneath which is a thin somatic epithelial cell layer. Internal to the epithelium are the spermatogonial stem cells and subsequent syncytial clusters of the germ cells as they progress through spermatogenesis; spermatozoa occupy the entire testis in sexually mature D. magna. We describe the structure of developing and mature spermatozoa; mature spermatozoa are non-flagellated, ovoid in shape with plasmalemma filapodia and are encased in an extracellular capsule. © 2017 Wiley Periodicals, Inc.

  12. Ultrastructure of the spermatogenesis of the cockle Anadara granosa L. (Bivalvia: Arcidae)

    Science.gov (United States)

    Suwanjarat, J.

    1999-11-01

    In this paper spermatogenesis and sperm ultrastructure of the cockle Anadara granosa are studied using transmission electron microscopy. The spermatocyte presents electron-dense vesicles and the arising axoneme that begins to form the flagellum. During spermatid differentiation, proacrosomal vesicles appear to migrate towards the presumptive anterior pole of the nucleus; eventually these vesicles become acrosome. The spermatozoon of Anadara granosa is of the primitive type. The acrosome, situated at the apex of the nucleus, is cap-shaped and deeply invaginated at the inner side. The spherical nucleus of the spermatozoon contains dense granular chromatin and shows invagination at the posterior poles. The centriole shows the classic nine triplets of microtubules. The middle piece consists of the centriolar complex surrounded by five giant mitochondria. It is shown that the ultrastructure of spermatozoa and spermiogenesis of Anadara granosa reveals a number of features that are common among bivalves.

  13. Mucuna pruriens restores spermatogenesis in mice after exposure to 2-methoxyethanol

    Directory of Open Access Journals (Sweden)

    Putu Oky Tania

    2015-12-01

    Full Text Available Background Increasing industrial activity is causing many problems in reproductive health, such as infertility. The factors causing infertility are hormones, infection, radiation, drugs and chemicals. One of these is 2-methoxyethanol (2-ME. The objective of this study was to evaluate the effect of Mucuna pruriens (MP seed fraction on spermatogenesis, including number of spermatogenic cells and spermatozoal membrane protein profiles after exposure to 2-ME in mice. Methods This study was of experimental design. Thirty mice were randomized into 5 groups, i.e. 2 control groups and 3 treatment groups. All mice were injected subcutaneously with 2-ME doses of 100mg/kg body weight (BW/day, for a period of 12 days. Positive (PC and negative controls (NC were treated with carboxy methyl cellulose (CMC. The three treatment groups were given MP seed fraction in doses of 14 (T1, 28 (T2 and 56 mg/kg BW (T3, respectively, from day 13 until day 64. Data on spermatogenic cells were collected from histological cross-sections and analyzed with one-way ANOVA. The spermatozoal membrane protein profile was identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE with silver staining and were analyzed descriptively. Results Administration of MP seed fractions resulted in significantly different numbers of spermatocytes I and round spermatids between PC and T1, T2, and T3. A protein with the molecular weight of 41.6 kDa was expressed in all groups except the positive controls, while a 24.5 kDa protein was expressed in the positive controls only. Conclusion MP seed fraction effectively recovers spermatogenesis loss in mice due to 2-ME exposure.

  14. BAZ1B is dispensable for H2AX phosphorylation on Tyrosine 142 during spermatogenesis

    Directory of Open Access Journals (Sweden)

    Tyler J. Broering

    2015-07-01

    Full Text Available Meiosis is precisely regulated by the factors involved in DNA damage response in somatic cells. Among them, phosphorylation of H2AX on Serine 139 (γH2AX is an essential signal for the silencing of unsynapsed sex chromosomes during male meiosis. However, it remains unknown how adjacent H2AX phosphorylation on Tyrosine 142 (pTyr142 is regulated in meiosis. Here we investigate the meiotic functions of BAZ1B (WSTF, the only known Tyr142 kinase in somatic cells, using mice possessing a conditional deletion of BAZ1B. Although BAZ1B deletion causes ectopic γH2AX signals on synapsed autosomes during the early pachytene stage, BAZ1B is dispensable for fertility and critical events during spermatogenesis. BAZ1B deletion does not alter events on unsynapsed axes and pericentric heterochromatin formation. Furthermore, BAZ1B is dispensable for localization of the ATP-dependent chromatin remodeling protein SMARCA5 (SNF2h during spermatogenesis despite the complex formation between BAZ1B and SMARCA5, known as the WICH complex, in somatic cells. Notably, pTyr142 is regulated independently of BAZ1B and is dephosphorylated on the sex chromosomes during meiosis in contrast with the presence of adjacent γH2AX. Dephosphorylation of pTyr142 is regulated by MDC1, a binding partner of γH2AX. These results reveal the distinct regulation of two adjacent phosphorylation sites of H2AX during meiosis, and suggest that another kinase mediates Tyr142 phosphorylation.

  15. Potential Spermatogenesis Recovery with Bone Marrow Mesenchymal Stem Cells in an Azoospermic Rat Model

    Directory of Open Access Journals (Sweden)

    Deying Zhang

    2014-07-01

    Full Text Available Non-obstructive azoospermia is the most challenging type of male infertility. Stem cell based therapy provides the potential to enhance the recovery of spermatogenesis following cancer therapy. Bone marrow-derived mesenchymal stem cells (BMSCs possess the potential to differentiate or trans-differentiate into multi-lineage cells, secrete paracrine factors to recruit the resident stem cells to participate in tissue regeneration, or fuse with the local cells in the affected region. In this study, we tested whether spermatogenically-induced BMSCs can restore spermatogenesis after administration of an anticancer drug. Allogeneic BMSCs were co-cultured in conditioned media derived from cultured testicular Sertoli cells in vitro, and then induced stem cells were transplanted into the seminiferous tubules of a busulfan-induced azoospermatic rat model for 8 weeks. The in vitro induced BMSCs exhibited specific spermatogonic gene and protein markers, and after implantation the donor cells survived and located at the basement membranes of the recipient seminiferous tubules, in accordance with what are considered the unique biological characteristics of spermatogenic stem cells. Molecular markers of spermatogonial stem cells and spermatogonia (Vasa, Stella, SMAD1, Dazl, GCNF, HSP90α, integrinβ1, and c-kit were expressed in the recipient testis tissue. No tumor mass, immune response, or inflammatory reaction developed. In conclusion, BMSCs might provide the potential to trans-differentiate into spermatogenic-like-cells, enhancing endogenous fertility recovery. The present study indicates that BMSCs might offer alternative treatment for the patients with azoospermatic infertility after cancer chemotherapy.

  16. The effect of eurycoma longifolia jack on spermatogenesis in estrogen-treated rats

    Directory of Open Access Journals (Sweden)

    Norhazlina Abdul Wahab

    2010-01-01

    Full Text Available INTRODUCTION: There is little data concerning the ability of Eurycoma longifolia Jack (EL to reverse the inhibitory effects of estrogen on testosterone production and spermatogenesis. The aim of the present study was to determine the effect of EL on testicular histology and sperm count in estrogen-treated male rats. METHODS: Adult male Sprague-Dawley rats weighing 200-250 g were divided into four groups of six rats each. Group A (control was given solvent in the same manner as the treated groups were given EL. Group B was treated with EL (8 mg/kg body weight orally. Group C was treated with estradiol (E2 (intramuscular dose of 500 μg/kg body weight, and group D received a combined treatment of oral EL and intramuscular E2. After fourteen consecutive days of treatment, rats from all groups were sacrificed and subjected to spermatogenic and epididymal sperm cell counts. RESULTS: The spermatogenic cell count in the E2-treated group was significantly decreased as compared to the control (p < 0.05 and EL+E2-treated groups (p < 0.05. A similar finding was found for the epididymal sperm count; the E2-treated group had a significant decrease in the count compared to the control (p < 0.05 and EL+E2-treated groups (p < 0.05. Rats that were treated with EL alone exhibited significantly higher sperm counts and sperm motility when compared to the control group (p < 0.05. CONCLUSIONS: EL extract acts as a potential agent for reversing the effects of estrogen by increasing spermatogenesis and sperm counts in rats after fourteen consecutive days of treatment.

  17. DDX4-EGFP transgenic rat model for the study of germline development and spermatogenesis.

    Science.gov (United States)

    Gassei, Kathrin; Sheng, Yi; Fayomi, Adetunji; Mital, Payal; Sukhwani, Meena; Lin, Chih-Cheng; Peters, Karen A; Althouse, Andrew; Valli, Hanna; Orwig, Kyle E

    2017-03-01

    Spermatogonial stem cells (SSC) are essential for spermatogenesis and male fertility. In addition, these adult tissue stem cells can be used as vehicles for germline modification in animal models and may have application for treating male infertility. To facilitate the investigation of SSCs and germ lineage development in rats, we generated a DEAD-box helicase 4 (DDX4) (VASA) promoter-enhanced green fluorescent protein (EGFP) reporter transgenic rat. Quantitative real-time polymerase chain reaction and immunofluorescence confirmed that EGFP was expressed in the germ cells of the ovaries and testes and was absent in somatic cells and tissues. Germ cell transplantation demonstrated that the EGFP-positive germ cell population from DDX4-EGFP rat testes contained SSCs capable of establishing spermatogenesis in experimentally infertile mouse recipient testes. EGFP-positive germ cells could be easily isolated by fluorescence-activated cells sorting, while simultaneously removing testicular somatic cells from DDX4-EGFP rat pup testes. The EGFP-positive fraction provided an optimal cell suspension to establish rat SSC cultures that maintained long-term expression of zinc finger and BTB domain containing 16 (ZBTB16) and spalt-like transcription factor 4 (SALL4), two markers of mouse SSCs that are conserved in rats. The novel DDX4-EGFP germ cell reporter rat described here combined with previously described GCS-EGFP rats, rat SSC culture and gene editing tools will improve the utility of the rat model for studying stem cells and germ lineage development. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction.

  18. Self-fertilization, sex allocation and spermatogenesis kinetics in the hypodermically inseminating flatwormMacrostomum pusillum.

    Science.gov (United States)

    Giannakara, Athina; Ramm, Steven A

    2017-05-01

    The free-living flatworm genus Macrostomum is an emerging model system for studying the links between sex allocation, sexual selection and mating system evolution, as well as the underlying developmental and physiological mechanisms responsible for wide intra- and inter-specific variability in reproductive phenotypes. Despite compelling comparative morphological evidence of sexual diversity, detailed experimental work on reproductive behaviour and physiology in Macrostomum has so far been largely limited to just two species, M. lignano and M. hystrix , an obligate and a preferential outcrosser, respectively. In this study, we establish that a third species, M. pusillum , exhibits a combination of reproductive traits strikingly different from both of its congeners. Unlike M. lignano , we demonstrate that M. pusillum does not adjust sex allocation or the speed of spermatogenesis to the prevailing social group size. M acrostomum pusillum 's relatively simple sperm morphology likely explains the short spermatogenesis duration we report, and is linked to a hypodermically inseminating mode of fertilization, which we show also means that these worms are capable of self-fertilization. Surprisingly, and unlike M. hystrix , selfing in isolated worms commences after only a short (if any) delay compared with the onset of reproduction in grouped individuals, with little evidence of differential inbreeding depression in 'isolated' progeny. These combined results suggest that, in nature, M. pusillum may be regularly selfing, in contrast to the congeners studied to date. Our findings highlight the rapid and correlated evolution of reproductive traits, and reinforce the utility of the genus Macrostomum for understanding the evolutionary and developmental mechanisms responsible for this diversity. © 2017. Published by The Company of Biologists Ltd.

  19. Autonomic dysfunction in primary Raynaud's phenomenon.

    Science.gov (United States)

    Koszewicz, M; Gosk-Bierska, I; Bilińska, M; Podemski, R; Budrewicz, S; Adamiec, R; Słotwiński, K

    2009-04-01

    The pathogenesis of Raynaud's phenomenon is still unclear. Neural and intravascular mechanisms are thought to be involved in the pathological process. The role of the autonomic nervous system is continually discussed, with particular attention to over-reactivity of the sympathetic part. The aim of this study was the clinical and electrophysiological analysis of autonomic nervous system function in patients with primary Raynaud's phenomenon. Thirty four patients with primary Raynaud's phenomenon and 31 sex and age-matched controls were examined. Neurological examination, modified Low's Questionnaire, orthostatic and sustained handgrip tests, conduction velocity study in three nerves, sympathetic skin response (SSR), and heart rate variability (HRV) during deep breathing and at rest with the fast Fourier transform were performed. In the clinical examinations, 35.3% of the primary Raynaud's patients presented sensory neuropathy, but this was not confirmed in the standard conduction velocity tests. The modified Low's Questionnaire revealed dysautonomy in 82% of the patients. Autonomic regulation during the orthostatic and handgrip tests were within the normal limits. HRV at rest and the E/I ratio were significantly lower in the patient group than in the controls, while HRV spectrum analysis revealed the predominance of the low-frequency band in the patients. These results indicate the presence of sympathetic dysregulation and impairment of parasympathetic modulation of heart function in primary Raynaud's patients. The different cardiovascular and sudomotor functions are not affected to the same degree. These observations might support the theory of a central impairment of autonomic function in primary Raynaud's phenomenon. Peripheral nerve lesion as a coexisting cause of the observed dysautonomy remains uncertain.

  20. Autonomic Neuropathy in Diabetes Mellitus

    OpenAIRE

    Verrotti, Alberto; Prezioso, Giovanni; Scattoni, Raffaella; Chiarelli, Francesco

    2014-01-01

    Diabetic autonomic neuropathy (DAN) is a serious and common complication of diabetes, often overlooked and misdiagnosed. It is a systemic-wide disorder that may be asymptomatic in the early stages. The most studied and clinically important form of DAN is cardiovascular autonomic neuropathy defined as the impairment of autonomic control of the cardiovascular system in patients with diabetes after exclusion of other causes. The reported prevalence of DAN varies widely depending on inconsistent ...

  1. Autonomic Fuselet Specification and Composition

    National Research Council Canada - National Science Library

    Mills, Peter H

    2006-01-01

    A framework for autonomic fuselet business logic development was developed, using semantic web services and workflow technologies to specify fuselet information needs, to define an executable workflow...

  2. Robotics and Autonomous Systems Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides an environment for developing and evaluating intelligent software for both actual and simulated autonomous vehicles. Laboratory computers provide...

  3. Morally autonomous practice?

    Science.gov (United States)

    Scott, P A

    1998-12-01

    The structures and contexts within which nurses work results in the moral agency and moral autonomy of the nurse being compromised. This claim results from a confusion of (1) the concept of autonomy with those of freedom and independence; and (2) a confusion of the notion of moral autonomy with that of autonomous professional practice. The drawing of appropriate distinctions allows clarification of the relevant concepts. It also underlines the responsibility of practitioners to recognize the moral dimension of their practice, and the moral implications of their actions, as they attempt to meet the health care needs of their patients and develop practice professionally.

  4. Autonomic epileptic seizures, autonomic effects of seizures, and SUDEP.

    Science.gov (United States)

    Moseley, Brian; Bateman, Lisa; Millichap, John J; Wirrell, Elaine; Panayiotopoulos, Chrysostomos P

    2013-03-01

    Many generalized tonic-clonic seizures are accompanied by profound autonomic changes. However, autonomic seizures and autonomic status epilepticus can also be seen with specific electroclinical syndromes (Panayiotopoulos syndrome), etiologies, and localizations. Such autonomic symptoms may impact cardiorespiratory function. While it is likely that several factors contribute to SUDEP, further study of both ictal respiratory and cardiac changes and underlying neuroanatomical mechanisms involved in autonomic seizure semiology are likely to provide important data to improve our understanding of the pathophysiology of this devastating condition. This paper will review the association between autonomic symptoms and epileptic seizures and will highlight the work of three young investigators. Drs. Lisa Bateman and Brian Moseley will review their work on cardiorespiratory effects of recorded seizures and how this assists in our understanding of SUDEP. Dr. John Millichap will review autonomic seizures and autonomic dysfunctions related to childhood epilepsy and will discuss the importance of expanded research efforts in this field. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Towards autonomous vehicular clouds

    Directory of Open Access Journals (Sweden)

    Stephan Olariu

    2011-09-01

    Full Text Available The dawn of the 21st century has seen a growing interest in vehicular networking and its myriad potential applications. The initial view of practitioners and researchers was that radio-equipped vehicles could keep the drivers informed about potential safety risks and increase their awareness of road conditions. The view then expanded to include access to the Internet and associated services. This position paper proposes and promotes a novel and more comprehensive vision namely, that advances in vehicular networks, embedded devices and cloud computing will enable the formation of autonomous clouds of vehicular computing, communication, sensing, power and physical resources. Hence, we coin the term, autonomous vehicular clouds (AVCs. A key feature distinguishing AVCs from conventional cloud computing is that mobile AVC resources can be pooled dynamically to serve authorized users and to enable autonomy in real-time service sharing and management on terrestrial, aerial, or aquatic pathways or theaters of operations. In addition to general-purpose AVCs, we also envision the emergence of specialized AVCs such as mobile analytics laboratories. Furthermore, we envision that the integration of AVCs with ubiquitous smart infrastructures including intelligent transportation systems, smart cities and smart electric power grids will have an enormous societal impact enabling ubiquitous utility cyber-physical services at the right place, right time and with right-sized resources.

  6. Autonomous Formation Flight

    Science.gov (United States)

    Schkolnik, Gerard S.; Cobleigh, Brent

    2004-01-01

    NASA's Strategic Plan for the Aerospace Technology Enterprise includes ambitious objectives focused on affordable air travel, reduced emissions, and expanded aviation-system capacity. NASA Dryden Flight Research Center, in cooperation with NASA Ames Research Center, the Boeing Company, and the University of California, Los Angeles, has embarked on an autonomous-formation-flight project that promises to make significant strides towards these goals. For millions of years, birds have taken advantage of the aerodynamic benefit of flying in formation. The traditional "V" formation flown by many species of birds (including gulls, pelicans, and geese) enables each of the trailing birds to fly in the upwash flow field that exists just outboard of the bird immediately ahead in the formation. The result for each trailing bird is a decrease in induced drag and thus a reduction in the energy needed to maintain a given speed. Hence, for migratory birds, formation flight extends the range of the system of birds over the range of birds flying solo. The Autonomous Formation Flight (AFF) Project is seeking to extend this symbiotic relationship to aircraft.

  7. Overview of the Autonomic Nervous System

    Science.gov (United States)

    ... process. Autonomic disorders may be reversible or progressive. Anatomy of the autonomic nervous system The autonomic nervous ... with acetylcholine and placed on the legs and forearm. Then, the volume of sweat is measured to ...

  8. Behavioural domain knowledge transfer for autonomous agents

    CSIR Research Space (South Africa)

    Rosman, Benjamin S

    2014-11-01

    Full Text Available , and Behavior Transfer in Autonomous Robots, AAAI 2014 Fall Symposium Series, 13-15 November 2014 Behavioural Domain Knowledge Transfer for Autonomous Agents Benjamin Rosman Mobile Intelligent Autonomous Systems Modelling and Digital Science Council...

  9. Autonomous Learner Model Resource Book

    Science.gov (United States)

    Betts, George T.; Carey, Robin J.; Kapushion, Blanche M.

    2016-01-01

    "Autonomous Learner Model Resource Book" includes activities and strategies to support the development of autonomous learners. More than 40 activities are included, all geared to the emotional, social, cognitive, and physical development of students. Teachers may use these activities and strategies with the entire class, small groups, or…

  10. Research Institute for Autonomous Precision Guided Systems

    National Research Council Canada - National Science Library

    Rogacki, John R

    2007-01-01

    ... vehicles, cooperative flight of autonomous aerial vehicles using GPS and vision information, cooperative and sharing of information in search missions involving multiple autonomous agents, multi-scale...

  11. Evolutionary Autonomous Health Monitoring System (EAHMS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — For supporting NASA's Robotics, Tele-Robotics and Autonomous Systems Roadmap, we are proposing the "Evolutionary Autonomous Health Monitoring System" (EAHMS) for...

  12. Autonomous Martian flying rover

    Science.gov (United States)

    1990-01-01

    A remotely programmable, autonomous flying rover is proposed to extensively survey the Martian surface environment. A Mach .3, solar powered, modified flying wing could cover roughly a 2000 mile range during Martian daylight hours. Multiple craft launched from an orbiting mother ship could provide near-global coverage. Each craft is envisioned to fly at about 1 km above the surface and measure atmospheric composition, pressure and temperature, map surface topography, and remotely penetrate the near subsurface looking for water (ice) and perhaps evidence of life. Data collected are relayed to Earth via the orbiting mother ship. Near surface guidance and control capability is an adaptation of current cruise missile technology. A solar powered aircraft designed to fly in the low temperature, low density, carbon dioxide Martian atmosphere near the surface appears feasible.

  13. Autonomous component carrier selection

    DEFF Research Database (Denmark)

    Garcia, Luis Guilherme Uzeda; Pedersen, Klaus; Mogensen, Preben

    2009-01-01

    management and efficient system operation. Due to the expected large number of user-deployed cells, centralized network planning becomes unpractical and new scalable alternatives must be sought. In this article, we propose a fully distributed and scalable solution to the interference management problem......Low-power base stations such as e.g. Femto-cells are one of the candidates for high data rate provisioning in local areas, such as residences, apartment complexes, business offices and outdoor hotspot scenarios. Unfortunately, the benefits are not without new challenges in terms of interference...... in local areas, basing our study case on LTE-Advanced. We present extensive network simulation results to demonstrate that a simple and robust interference management scheme, called autonomous component carrier selection allows each cell to select the most attractive frequency configuration; improving...

  14. RFX2 is a candidate downstream amplifier of A-MYB regulation in mouse spermatogenesis

    Directory of Open Access Journals (Sweden)

    Kistler Malathi K

    2009-12-01

    Full Text Available Abstract Background Mammalian spermatogenesis involves formation of haploid cells from the male germline and then a complex morphological transformation to generate motile sperm. Focusing on meiotic prophase, some tissue-specific transcription factors are known (A-MYB or suspected (RFX2 to play important roles in modulating gene expression in pachytene spermatocytes. The current work was initiated to identify both downstream and upstream regulatory connections for Rfx2. Results Searches of pachytene up-regulated genes identified high affinity RFX binding sites (X boxes in promoter regions of several new genes: Adam5, Pdcl2, and Spag6. We confirmed a strong promoter-region X-box for Alf, a germ cell-specific variant of general transcription factor TFIIA. Using Alf as an example of a target gene, we showed that its promoter is stimulated by RFX2 in transfected cells and used ChIP analysis to show that the promoter is occupied by RFX2 in vivo. Turning to upstream regulation of the Rfx2 promoter, we identified a cluster of three binding sites (MBS for the MYB family of transcription factors. Because testis is one of the few sites of A-myb expression, and because spermatogenesis arrests in pachytene in A-myb knockout mice, the MBS cluster implicates Rfx2 as an A-myb target. Electrophoretic gel-shift, ChIP, and co-transfection assays all support a role for these MYB sites in Rfx2 expression. Further, Rfx2 expression was virtually eliminated in A-myb knockout testes. Immunohistology on testis sections showed that A-MYB expression is up-regulated only after pachytene spermatocytes have clearly moved away from the tubule wall, which correlates with onset of RFX2 expression, whereas B-MYB expression, by contrast, is prevalent only in earlier spermatocytes and spermatogonia. Conclusion With an expanding list of likely target genes, RFX2 is potentially an important transcriptional regulator in pachytene spermatocytes. Rfx2 itself is a good candidate to be

  15. Expression profiling of rainbow trout testis development identifies evolutionary conserved genes involved in spermatogenesis

    Directory of Open Access Journals (Sweden)

    Esquerré Diane

    2009-11-01

    Full Text Available Abstract Background Spermatogenesis is a late developmental process that involves a coordinated expression program in germ cells and a permanent communication between the testicular somatic cells and the germ-line. Current knowledge regarding molecular factors driving male germ cell proliferation and differentiation in vertebrates is still limited and mainly based on existing data from rodents and human. Fish with a marked reproductive cycle and a germ cell development in synchronous cysts have proven to be choice models to study precise stages of the spermatogenetic development and the germ cell-somatic cell communication network. In this study we used 9K cDNA microarrays to investigate the expression profiles underlying testis maturation during the male reproductive cycle of the trout, Oncorhynchus mykiss. Results Using total testis samples at various developmental stages and isolated spermatogonia, spermatocytes and spermatids, 3379 differentially expressed trout cDNAs were identified and their gene activation or repression patterns throughout the reproductive cycle were reported. We also performed a tissue-profiling analysis and highlighted many genes for which expression signals were restricted to the testes or gonads from both sexes. The search for orthologous genes in genome-sequenced fish species and the use of their mammalian orthologs allowed us to provide accurate annotations for trout cDNAs. The analysis of the GeneOntology terms therefore validated and broadened our interpretation of expression clusters by highlighting enriched functions that are consistent with known sequential events during male gametogenesis. Furthermore, we compared expression profiles of trout and mouse orthologs and identified a complement of genes for which expression during spermatogenesis was maintained throughout evolution. Conclusion A comprehensive study of gene expression and associated functions during testis maturation and germ cell differentiation in

  16. Vacuolar-ATPase isoform a2 regulates macrophages and cytokine profile necessary for normal spermatogenesis in testis.

    Science.gov (United States)

    Jaiswal, Mukesh K; Katara, Gajendra K; Mallers, Timothy; Chaouat, Gerard; Gilman-Sachs, Alice; Beaman, Kenneth D

    2014-08-01

    a2V is required for maturation of sperm. The decreased expression of a2V at the feto-maternal interphase causes poor pregnancy outcome. The present study examined the role of a2V in spermatogenesis and inflammatory network in the testis. A single dose of anti-a2V mouse IgG or mouse IgG isotype (3 μg/animal) was injected i.p. into male mice on alternate days for 10 days. Anti-a2V-treated males exhibit severe deficiencies of spermatogenesis, which is indicated by the presence of less numbers of postmeiotic cells. Sperm counts and sperm motility were reduced significantly in anti-a2V-treated males. The release of the cleaved a2NTD was significantly lower in anti-a2V-treated testes. The TMs were identified as M2-like macrophages, and this population and the expression of various cytokines/chemokines (Tgf-β, Il-6, Nos2, Tnf, Lif, Mcp1, Ccl5) were decreased significantly in anti-a2V-treated testis compared with control testis. Moreover, the cleaved a2NTD acts as a key mediator of TMs and significantly up-regulates the secretion of testicular cytokines/chemokines, which are associated with normal spermatogenesis. When these anti-a2V-treated males were used for mating with normal females, the number of implantation sites was decreased significantly in the females mated with anti-a2V-treated males than the females mated with control males. These observations suggest that a2V plays a crucial role in spermatogenesis by regulating testicular immune responses, and its inhibition in males leads to poor pregnancy outcome in females. © 2014 Society for Leukocyte Biology.

  17. Impaired hypothalamic-pituitary-testicular axis activity, spermatogenesis, and sperm function promote infertility in males with lead poisoning.

    Science.gov (United States)

    Gandhi, Jason; Hernandez, Rafael J; Chen, Andrew; Smith, Noel L; Sheynkin, Yefim R; Joshi, Gargi; Khan, Sardar Ali

    2017-04-01

    Lead poisoning is a stealthy threat to human physiological systems as chronic exposure can remain asymptomatic for long periods of time before symptoms manifest. We presently review the biophysical mechanisms of lead poisoning that contribute to male infertility. Environmental and occupational exposure of lead may adversely affect the hypothalamic-pituitary-testicular axis, impairing the induction of spermatogenesis. Dysfunction at the reproductive axis, namely testosterone suppression, is most susceptible and irreversible during pubertal development. Lead poisoning also appears to directly impair the process of spermatogenesis itself as well as sperm function. Spermatogenesis issues may manifest as low sperm count and stem from reproductive axis dysfunction or testicular degeneration. Generation of excessive reactive oxygen species due to lead-associated oxidative stress can potentially affect sperm viability, motility, DNA fragmentation, membrane lipid peroxidation, capacitation, hyperactivation, acrosome reaction, and chemotaxis for sperm-oocyte fusion, all of which can contribute to deter fertilization. Reproductive toxicity has been tested through cross-sectional analysis studies in humans as well as in vivo and in vitro studies in animals.

  18. Proliferating cell nuclear antigen as a molecular biomarker for spermatogenesis in PTU-induced hypothyroidism of rats.

    Science.gov (United States)

    Tousson, Ehab; Ali, Ehab M M; Ibrahim, Wafaa; Mansour, Mohammed A

    2011-07-01

    The thyroid hormone has few serious effects on the testes except during the neonatal stage. There is little knowledge concerning the prolonged effect of thyroid hormone deficiency throughout the rat's life span and its effect on spermatogenesis. Proliferating cell nuclear antigen (PCNA) is a nuclear matrix protein, which is essential for multiple cell cycle pathways. Here we used PCNA immunohistochemistry as a marker to differentiate between the testes of control and hypothyroid rats. About 20 rats were equally divided into 2 groups; the first group was the control group, while the second group was the experimental group in which rats were fed 0.05% 6-n-propyl thiouracil (PTU) in drinking water for 6 weeks. Immunohistochemistry, using an antibody against PCNA, showed at least 3 differences in the pattern of PCNA immunoreactivity (PCNA-ir). First, PCNA-ir was not detected in Sertoli and Leydig cells in the testes of control rats and detected in some of the hypothyroid rats. Second, in the control group more than 96% of spermatogonia were PCNA-positive cells; however, hypothyroidism caused the reduction to approximately 25% PCNA staining in spermatogonia. The third difference was in the abnormal distribution of spermatogonia seen in the hypothyroid rat testis, not in the control one. These results suggest that prepubertal hypothyroidism affects the proliferation of spermatogenic cells leading to impaired spermatogenesis and that PCNA index is a useful marker for assessing germ cell kinetics and spermatogenesis in prepubertal hypothyroidism.

  19. Spermatogenesis and nucleolar behavior in Triatoma vandae and Triatoma williami (Hemiptera, Triatominae).

    Science.gov (United States)

    Pereira, N P; Alevi, K C C; Mendonça, P P; Azeredo-Oliveira, M T V

    2015-10-09

    This study describes spermatogenesis in Triatoma vandae and the nucleolar behavior of T. vandae and Triatoma williami, with a cytotaxonomic focus. Analysis of mitotic and meiotic metaphases of T.vandae confirms the species karyotype. T. vandae presents some characteristics during meiosis that differentiate it from T. williami, including the presence of a chromocenter with two sex chromosomes individualized during early prophase, and the presence of a bi- or tripartite corpuscle inpolyploid nuclei. It was possible to observe the compaction of chromatin during prophase resulting in holocentric chromosomes. During metaphase,the autosomes presented a ring shape and the sex chromosomes were in the center of the ring. These chromosomes were separated in anaphase. Although it is common, we did not observe the phenomenon of late migration of the sex chromosomes. By means of silver ion impregnation it was possible to describe nucleologenesis in T. vandae and T. williami. In both species we observed persistence of the nucleolar material duringmeiosis. In addition to the cells in meiotic division, we also observed the presence of polyploid nuclei in the seminiferous tubule walls that nourish the cells during cell division. The nucleolar markings reflect their capacity for synthetic activity. T. vandae and T. williami presented only one nucleolar corpuscle, which reflects low synthetic activity. This study confirms the karyotype of T. vandae, describes characteristics that differentiate T. vandae and T. williami during meiosis, and describes the phenomenon of nucleolar persistence in both species.

  20. Hormonal stimulation of the recovery of spermatogenesis following chemo- or radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Meistrich, M.L. [Univ. of Texas, M.D. Anderson Cancer Center, Dept. of Experimental Radiation Oncology, Houston, Texas (United States)

    1998-01-01

    Radiation and chemotherapeutic drugs produce prolonged depression of sperm counts in rodents and humans. Previously, three approaches have been developed in experimental animals that have had some success in preventing or reversing this toxicity. These approaches included pretreatment with hormones that suppress spermatogenesis, stimulation of stem cell number, and supplementation with testosterone. A different rationale for the ability of particular hormonal treatments to reverse prolonged azoospermia is presented in this review. In many cases prolonged azoospermia occurs even though the stem spermatogonia survive the toxic insult, but the differentiation of these spermatogonia to produce sperm fails. In the rat, the block appears to be at the differentiation of the A spermatogonia. Hormone treatments with testosterone or with GnRH agonists, which suppress intratesticular testosterone levels, relieve this block and result in the production of differentiating cells. When the hormone treatment is stopped the production of differentiating cells continues, mature sperm are produced, and fertility is restored. If a similar mechanism can be demonstrated to hold in humans, the fertility of men who have been rendered infertile by treatments for testicular and other cancers could be improved. (au). 100 refs.

  1. The Dnmt3L ADD Domain Controls Cytosine Methylation Establishment during Spermatogenesis

    Directory of Open Access Journals (Sweden)

    Georgios Vlachogiannis

    2015-02-01

    Full Text Available A critical aspect of mammalian gametogenesis is the reprogramming of genomic DNA methylation. The catalytically inactive adaptor Dnmt3L is essential to ensuring this occurs correctly, but the mechanism by which it functions is unclear. Using gene targeting to engineer a single-amino-acid mutation, we show that the Dnmt3L histone H3 binding domain (ADD is necessary for spermatogenesis. Genome-wide single-base-resolution DNA methylome analysis of mutant germ cells revealed overall reductions in CG methylation at repetitive sequences and non-promoter CpG islands. Strikingly, we also observe an even more severe loss of non-CG methylation, suggesting an unexpected role for the ADD in this process. These epigenetic deficiencies were coupled with defects in spermatogonia, with mutant cells displaying marked changes in gene expression and reactivation of retrotransposons. Our results demonstrate that the Dnmt3L ADD is necessary for Dnmt3L function and full reproductive fitness.

  2. Expression of Prothymosin alpha during the spermatogenesis of the spotted ray Torpedo marmorata.

    Science.gov (United States)

    Prisco, Marina; Donizetti, Aldo; Aniello, Francesco; Locascio, Annamaria; Del Giudice, Giuseppina; Agnese, Marisa; Angelini, Francesco; Andreuccetti, Piero

    2009-10-01

    In this study, we show that Prothymosin alpha (Ptma), a small, unfolded, negatively charged protein, is present in the cartilaginous fish Torpedo marmorata. The ptma gene is functional and peculiarly controlled during the male spermatogenesis of T. marmorata, as revealed by in situ hybridization and by immunocytochemistry studies. The data show that the ptma transcript is present in stage-specific germ cells, i.e. spermatocytes II and round spermatids. The Ptma protein is detectable in spermatocytes II, in round and elongated spermatids as well as in spermatozoa before their release from cysts, while it is not evident in spermatozoa located in male genital tracts. The ptma transcript and protein are also evident in some Leydig cells, located among maturing cysts containing meiotic and differentiating male cells. No expression for ptma is observed within Sertoli cells. Furthermore, immunolocalization procedures demonstrate that the protein is preferentially localized in the cytoplasm, whereas a nuclear localization is observed in round and elongated spermatids. The possibility that Ptma is involved in testis activity is discussed.

  3. Spermatogenesis in young adult patients with beta-thalassaemia major long-term treated with desferrioxamine.

    Science.gov (United States)

    De Sanctis, V; Borsari, G; Brachi, S; Govoni, M; Carandina, G

    2008-03-01

    Since the introduction of hypertransfusion and intensive iron chelation therapy, patients with homozygous beta-thalassaemia major (TM) achieve adulthood. Many patients grow and develop normal hoping for marriage and to have a family. Therefore the question of fertility potential in this adult group of TM patients has become paramount. We report the semen parameters, the endocrine functions and serum zinc levels in 12 young adult TM patients. Their mean age was 24.8 years. Six patients (50%) had a normal sperm count, motility and morphology. While the remaining patients had oligospermia (sperm concentration plasma zinc, serum ferritin and seminal parameters. Nevertheless we observed that serum ferritin levels were lower (mean 543 ng/ml) in TM patients with abnormal seminal parameters (count and motility) compared to TM patients with normal seminal parameters (mean serum ferritin 1276 ng/ml; p<0.01). In conclusion, impairment of semen parameters may be a negative effect of intensive chelation therapy. Clearly, further investigations are required to evaluate if these adverse effects can be reduced or prevented, and if the existing spermatogenesis damage is reversible.

  4. Investigation of the ultrastructure of Dendrocoelum constrictum (Platyhelminthes, Tricladida) spermatogenesis and mature spermatozoa.

    Science.gov (United States)

    Harrath, Abdel Halim; Gammoudi, Mehrez; Mansour, Lamjed; Ahmed, Mukhtar; Sirotkin, Alexander V; Al Omar, Suliman Y; Ibrahim, Khalid E; Alwasel, Saleh H

    2014-09-01

    To add to our understanding of dendrocoelid spermatozoa and to describe additional phylogenetic characters, the ultrastructure of the testis was investigated in the subterranean freshwater planarian Dendrocoelum constrictum. This is the first study investigating spermatogenesis and spermatozoon ultrastructure in a subterranean freshwater planarian species. We found that the basic structure of spermatozoa in D. constrictum is similar to that of other Tricladida that have been studied previously. In fact, D. constrictum spermatozoa possess an elongated nucleus, one giant mitochondrion, and two subterminal flagella with a 9+'1' pattern. The flagella emerge together from one side of the spermatozoon. However, D. constrictum has some characteristics that have not yet been described for other freshwater planarians. In fact, the number of cortical microtubules reaches the maximum number in the anterior and middle part of region I, and then decrease until they disappear towards the posterior extremity of the spermatozoon. The extreme tip of the anterior region of the spermatozoon exhibits a specific external ornamentation of the plasma membrane. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  5. A GFP trap study uncovers the functions of Gilgamesh protein kinase in Drosophila melanogaster spermatogenesis.

    Science.gov (United States)

    Nerusheva, O O; Dorogova, N V; Gubanova, N V; Yudina, O S; Omelyanchuk, L V

    2009-05-01

    The function of the gene gilgamesh (89B9-12) encoding a casein kinase in Drosophila spermatogenesis was studied. The chimeric Gilgamesh-GFP protein in spermatocytes is cortically located. In the polar and apolar spermatocytes, it concentrates at the terminal ends of the fusome, the organelle that passes through the system of ring canals of the spermatocyte cyst. At the stage of spermatid elongation, the protein associates with the nucleus. A spot of the highest Gilgamesh-GFP concentration in the nucleus co-localizes with gamma-tubulin in the basal body. At later stages, Gilgamesh is localized to the individualization complex (IC), leaving the nuclei somewhat before the IC investment cones, as detected by actin binding. The sterile mutation due to the gilgamesh gene leads to the phenotype of scattered nuclei and altered structure of actin cones in the individualizing spermatid cyst. Ultrastructural evidence confirmed defective spermatid individualization due to the mutation. The phylogenetic origin of the protein, and the connection between vesicular trafficking and spermatid individualization, are discussed.

  6. Ultrastructural characteristics of spermatogenesis in Pallas's mastiff bat, Molossus molossus (Chiroptera: Molossidae).

    Science.gov (United States)

    Beguelini, Mateus R; Taboga, Sebastião R; Morielle-Versute, Eliana

    2012-07-01

    Despite the large number of species, their wide distribution, and unique reproductive characteristics, Neotropical bats have been poorly studied, and important aspects of the reproduction of these animals have not been elucidated. We made an ultrastructural analysis of spermatogenesis in Molossus molossus (Molossidae). The process of spermatogonial differentiation is similar to that found in other bats and is also relatively similar to that of Primates, with three main spermatogonia types: A(d), A(p), and B. Meiotic divisions proceed similarly to those of most mammals, and spermiogenesis is clearly divided into 12 steps, in the middle of the range known for bats (9-16 steps). Formation of the acrosome is similar to that known from other mammals; however, the ultrastructure of spermatozoa was found to have unique characteristics, including many wavy acrosomal projections on its surface, which seems to be specific for the family Molossidae. Comparing the ultrastructure of the spermatozoon of M. molossus with other bats already study, we observed that three characters vary: morphology of the outer dense fibers, of the perforatorium, and of the spermatozoon head. The great similarity of morphological characters between M. molossus and Platyrrhinus lineatus suggests that M. molossus is more closely related to the Phyllostomidae than to the Rhinolophidae and the Vespertilionidae. Copyright © 2012 Wiley Periodicals, Inc.

  7. Analysis of topological organization of chromatin during spermatogenesis in mouse testis

    Directory of Open Access Journals (Sweden)

    Narayan Gopeshwar

    2004-01-01

    Full Text Available Eukaryotic chromatin is organized as radial DNA loops with periodical attachments to an underlying nucleoskeleton known as nuclear matrix. This higher order chromatin organization is revealed upon high salt extraction of cells. To understand the sequential change in the functional organization of chromatin during spermatogenesis, we have analysed the higher order organization of chromatin in different testicular cell types and the epididymal sperm of laboratory mouse. The expansion and contraction of the nucleoid DNA following 2 M NaCl extraction was measured in a fluorescence microscope using ethidium bromide (2.5-200 mg/mL as an intercalating dye to induce DNA positive supercoils. While the halo size varied among cell types (pachytene DNA most extended, round spermatid least, 5 mg/mL ethidium bromide (EtBr removed maximum negative supercoils in all the cell types. At higher EtBr concentrations, maximum positive supercoiling occured in pachytene DNA loops. Consistent with this, the pachytene looped domains were maximally sensitive to DNase I, while the elongated spermatids and sperms were highly resistant. Our data suggest that pachytene DNA is in the most open chromatin conformation of all testicular cell types, while round spermatids show the most compact conformation in terms of EtBr intercalation.

  8. Protection from radiation-induced damage to spermatogenesis by hormone treatment

    International Nuclear Information System (INIS)

    Kurdoglu, B.; Wilson, G.; Parchuri, N.; Ye, W.; Meistrich, M.L.

    1994-01-01

    Infertility caused by killing of the spermatogonial stem cells occurs frequently in men treated for cancer with radiotherapy and chemotherapy. We investigated whether pretreatment of rats with testosterone plus estradiol, which reversibly inhibits the completion of spermatogenesis and protects spermatogonial stem cells from procarbazine-induced damage, would also protect these cells from radiation. Adult male LBNF rats were implanted for 6 weeks with capsules containing testosterone and estradiol and then irradiated with doses from 2.5-7.0 Gy. Controls were irradiated with 1.8-3.5 Gy. Implants were removed 1 day after irradiation, and all animals were killed 10 weeks later for assessment of stem cell survival by counting repopulating tubules in histological sections and by sperm head counts. At doses of 2.5 and 3.5 Gy the repopulation indices and sperm head counts were significantly higher (P < 0.001) in the rats treated with testosterone and estradiol than in the controls. Protection factors calculated from the dose-response curves were in the range of 1.5-2.2. Elucidation of the mechanism of protection is essential to apply it to clinical situations. The fact that the spermatogonia are protected against radiation as well as procarbazine indicates that the mechanism does not involve drug delivery or metabolism. 32 refs., 3 figs

  9. Acetylation-Mediated Proteasomal Degradation of Core Histones during DNA Repair and Spermatogenesis

    Science.gov (United States)

    Qian, Min-Xian; Pang, Ye; Liu, Cui Hua; Haratake, Kousuke; Du, Bo-Yu; Ji, Dan-Yang; Wang, Guang-Fei; Zhu, Qian-Qian; Song, Wei; Yu, Yadong; Zhang, Xiao-Xu; Huang, Hai-Tao; Miao, Shiying; Chen, Lian-Bin; Zhang, Zi-Hui; Liang, Ya-Nan; Liu, Shan; Cha, Hwangho; Yang, Dong; Zhai, Yonggong; Komatsu, Takuo; Tsuruta, Fuminori; Li, Haitao; Cao, Cheng; Li, Wei; Li, Guo-Hong; Cheng, Yifan; Chiba, Tomoki; Wang, Linfang; Goldberg, Alfred L.; Shen, Yan; Qiu, Xiao-Bo

    2013-01-01

    SUMMARY Histone acetylation plays critical roles in chromatin remodeling, DNA repair, and epigenetic regulation of gene expression, but the underlying mechanisms are unclear. Proteasomes usually catalyze ATP- and polyubiquitin-dependent proteolysis. Here we show that the proteasomes containing the activator PA200 catalyze the polyubiquitin-independent degradation of histones. Most proteasomes in mammalian testes (“spermatoproteasomes”) contain a spermatid/sperm-specific α-subunit α4s/PSMA8 and/or the catalytic β-subunits of immunoproteasomes in addition to PA200. Deletion of PA200 in mice abolishes acetylation-dependent degradation of somatic core histones during DNA double-strand breaks, and delays core histone disappearance in elongated spermatids. Purified PA200 greatly promotes ATP-independent proteasomal degradation of the acetylated core histones, but not polyubiquitinated proteins. Furthermore, acetylation on histones is required for their binding to the bromodomain-like regions in PA200 and its yeast ortholog, Blm10. Thus, PA200/Blm10 specifically targets the core histones for acetylation-mediated degradation by proteasomes, providing mechanisms by which acetylation regulates histone degradation, DNA repair, and spermatogenesis. PMID:23706739

  10. Fertility impairment with defective spermatogenesis and steroidogenesis in male zebrafish lacking androgen receptor.

    Science.gov (United States)

    Tang, Haipei; Chen, Yu; Wang, Le; Yin, Yike; Li, Gaofei; Guo, Yin; Liu, Yun; Lin, Haoran; Cheng, Christopher H K; Liu, Xiaochun

    2018-02-01

    The pivotal role of androgen receptor (AR) in regulating male fertility has attracted much research attention in the past two decades. Previous studies have shown that total AR knockout would lead to incomplete spermatogenesis and lowered serum testosterone levels in mice, resulting in azoospermia and infertility. However, the precise physiological role of ar in controlling fertility of male fish is still poorly understood. In this study, we have established an ar knockout zebrafish line by transcription activator-like effectors nucleases. Homozygous ar mutant male fish with smaller testis size were found to be infertile when tested by natural mating. Intriguingly, a small amount of mature spermatozoa was observed in the ar mutant fish. These mature spermatozoa could fertilize healthy oocytes, albeit with a lower fertilization rate, by in vitro fertilization. Moreover, the expression levels of most steroidogenic genes in the testes were significantly elevated in the ar mutants. In contrast, the levels of estradiol and 11-ketotestosterone (11-KT) were significantly decreased in the ar mutants, indicating that steroidogenesis was defective in the mutants. Furthermore, the protein level of LHβ in the serum decreased markedly in the ar mutants when compared with wild-type fish, probably due to the positive feedback from the diminished steroid hormone levels.

  11. Occurrence of "Nuages" and "Lamellae Anulata" during spermatogenesis in Dermatobia hominis (Diptera: Cuterebridae

    Directory of Open Access Journals (Sweden)

    Irani Quagio-Grassiotto

    1995-08-01

    Full Text Available Various types of "nuages" and "lamellae anulata" can be found during Dermatobia hominis spermatogenesis. In spermatogonia, the "nuages" occur as granules juxtaposed to the cytoplasmic face of the nuclear envelope or as cytoplasmic granules similar to glycogen granules. In spermatocytes, in addition to the "nuages", dense spherical bodies of approximately 1.0 µm in diameter are also observed. In the spermatids the "nuages" can be of the following types: perinuclear granules, spherical granules with diameters varying in length from 0.5 to 1.0 µm, granules similar to glycogen granules, granules with variable diameters which accumulate at the flagellum base forming the centriole adjunct, or remain in the cytoplasm. "Nuages" can also be observed in these cellular types as dense masses, without a definite outline and are common to animal germinal cells in general. The "lamellae anulata" on the other hand, are observed only in spermatocytes I and in early spermatids, being always immersed in electron-dense material of indefinite outline. In spermatids, the "lamellae anulata" are close to the nuclear envelope suggesting, in spite of opposing opinions, that these cells are envolved in the synthesis and transport of material from the nucleus to the cytoplasm.

  12. Effects of Ferula assa-foetida extract on spermatogenesis of rats

    Directory of Open Access Journals (Sweden)

    2017-11-01

    Full Text Available Background and objectives: Ferula assa-foetida is an herbaceous perennial plant which belongs to Apiaceae family. It is native to the east and central parts of Iran. This old traditional medicine has been used as antispasmodic, carminative, expectorant, laxative, sedative, stimulant, emmenagogue and vermifuge. In addition to the several therapeutic effects of the plant, it is known as an aphrodisiac herb traditionally; therefore, the present study has evaluated the effect of hydro-alcoholic extract of F. assa-foetida on spermatogenesis of rats. Methods: The seeds of the plant (500 g were identified and extracted by aqueous ethanol 80% using maceration methods (3×48 h.Adult male rats (6 weeks were orally treated with 50 mg/kg body weight of extract for 6 weeks. The extract was dispersed in distilled water. Control group received distilled water for the same duration. Some fertility parameters including sperm count, morphology and mobility of sperms with serum levels of testosterone, estrogen, luteinizing hormone (LH and follicle-stimulating hormone (FSH were evaluated using immunoassay methods.  Results: Sperm parameters and levels of testosterone and LH were significantly improved in the treated group compared to the control group. Conclusion: The results revealed that extract of F. assa-foetida significantly (p

  13. Evaluating the ameliorative efficacy of Spirulina platensis on spermatogenesis and steroidogenesis in cadmium-intoxicated rats.

    Science.gov (United States)

    Farag, Mayada R; Abd El-Aziz, R M; Ali, H A; Ahmed, Sahar A

    2016-02-01

    The present study was conducted to evaluate the ameliorative efficacy of Spirulina platensis (SP) on reproductive dysfunctions induced by cadmium chloride (CdCl2) in male rats. Rats (n = 40) were divided into five groups (eight rats/each). Group 1: served as control without any treatment. Group 2: Rats were administered SP (150 mg/kg body weight (BW)) in drinking water for 10 days. Group 3: Rats were subcutaneously injected with CdCl2 (2 mg/kg BW) daily for 10 days. Group 4: Rats were co-treated with both CdCl2 (2 mg/kg BW) and SP (150 mg/kg BW) daily for 10 days (SP prophylactic group). Group 5: Rats received CdCl2 for 10 days followed by administration of SP alone in drinking water daily for another 30 days with the same mentioned routes and doses (SP treatment group). From our findings, the administration of SP alone or co-administration with Cd significantly attenuated the harmful effects of Cd, suggesting its beneficial role in improving spermatogenesis and steroidogenesis after Cd exposure.

  14. Expression of Aire and the early wave of apoptosis in spermatogenesis.

    Science.gov (United States)

    Schaller, Claudia E; Wang, Clifford L; Beck-Engeser, Gabriele; Goss, Lindsie; Scott, Hamish S; Anderson, Mark S; Wabl, Matthias

    2008-02-01

    Expression of the autoimmune regulator (Aire) protein in mice and humans is thought to be restricted to the medullary epithelial and monocyte-dendritic cells of the thymus. There it mediates expression and presentation of a large variety of proteins, including those that are peripheral organ-specific and are not expressed by other thymocytes. In this way, self-reactive T lymphocytes that would attack peripheral cells producing these proteins are confronted with the self-Ags and, as a consequence, are deleted. In this study, we show that Aire mRNA is also expressed in the testis--another tissue with promiscuous gene expression. Aire protein, however, is expressed only sporadically in spermatogonia and spermatocytes. Transcription of genes that are under Aire control in the thymus is unaffected by Aire in the testis. However, in mice with a disrupted Aire gene, the scheduled apoptotic wave of germ cells, which is necessary for normal mature spermatogenesis, is reduced, and sporadic apoptosis in adults is increased. Because Rag-1 deficiency does not abolish the effect, the adaptive immune system is not involved. We suggest that there is a link between the scheduled and sporadic apoptotic processes and propose that scheduled apoptosis provides a counterselection mechanism that keeps the germline stable.

  15. Hormonal stimulation of the recovery of spermatogenesis following chemo- or radiotherapy

    International Nuclear Information System (INIS)

    Meistrich, M.L.

    1998-01-01

    Radiation and chemotherapeutic drugs produce prolonged depression of sperm counts in rodents and humans. Previously, three approaches have been developed in experimental animals that have had some success in preventing or reversing this toxicity. These approaches included pretreatment with hormones that suppress spermatogenesis, stimulation of stem cell number, and supplementation with testosterone. A different rationale for the ability of particular hormonal treatments to reverse prolonged azoospermia is presented in this review. In many cases prolonged azoospermia occurs even though the stem spermatogonia survive the toxic insult, but the differentiation of these spermatogonia to produce sperm fails. In the rat, the block appears to be at the differentiation of the A spermatogonia. Hormone treatments with testosterone or with GnRH agonists, which suppress intratesticular testosterone levels, relieve this block and result in the production of differentiating cells. When the hormone treatment is stopped the production of differentiating cells continues, mature sperm are produced, and fertility is restored. If a similar mechanism can be demonstrated to hold in humans, the fertility of men who have been rendered infertile by treatments for testicular and other cancers could be improved. (au)

  16. Study of spermatogenesis fetal testis exposed noise stress during and after natal period in rat.

    Science.gov (United States)

    Jalali, Maryamalsadat; Hemadi, Masoud; Saki, Ghasem; Sarkaki, Alireza

    2013-10-01

    Noise stress is dangerous natural contaminant that produces harmful physiological, psychological and morphological outcomes to the body. So this study was conducted in order to investigate the effects of noise stress on the parenchyma of testis. Healthy mature females rats (n = 20) were mated with the mature male rats and then randomly allocated equally either to experimental or control groups. Experimental group has given daily noise stress up to birth their child. In the second step, the child's pregnant rats of experimental group were distributed to three subgroups as follow: group I (without exposure to noise stress), group II (exposure to noise for 8 weeks) and group III (exposure to noise for 14 weeks) for morphometric analysis of their child's testicles by sacrificing of them at weeks 14. In general, the testes of non-exposed group were grown larger than ones in the noise exposed groups. Moreover, the testes of the experimental group 1 were larger than the other experimental groups. Indeed, the rate of atrophic seminiferous tubules and jumbled appearance of the interstitial space were more observed in the noise stress exposed group than non-exposed ones. In addition, seminiferous tubules analysis revealed that the characteristics of interstitial space cells and epithelial germinative cells of the seminiferous tubules in the control group were better than the noise exposed groups. It seems that the noise stress has negative influences on the fertility of male based on enhancing of the apoptotic process induced by pathogenesis stress and suppressing the kinetics spermatogenesis.

  17. Cybersecurity for aerospace autonomous systems

    Science.gov (United States)

    Straub, Jeremy

    2015-05-01

    High profile breaches have occurred across numerous information systems. One area where attacks are particularly problematic is autonomous control systems. This paper considers the aerospace information system, focusing on elements that interact with autonomous control systems (e.g., onboard UAVs). It discusses the trust placed in the autonomous systems and supporting systems (e.g., navigational aids) and how this trust can be validated. Approaches to remotely detect the UAV compromise, without relying on the onboard software (on a potentially compromised system) as part of the process are discussed. How different levels of autonomy (task-based, goal-based, mission-based) impact this remote characterization is considered.

  18. Autonomous ships in sight: Starting signal for the unmanned merchant shipping project MUNIN

    OpenAIRE

    Burmeister, Hans-Christoph

    2012-01-01

    Autonomous and unmanned vessels are seen as a key element in a competitive and sustainable European shipping industry in the future. For this reason, a new research project called MUNIN (Maritime Unmanned Navigation through Intelligence in Networks) started this September aiming to develop a concept for autonomous ships and to prove its feasibility. It is named after the Old Norse raven, Munin that flew around the world each day without guidance, gathering information and safely returning it ...

  19. Cranial Autonomic Symptoms in Migraine

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-11-01

    Full Text Available Cranial autonomic symptoms (CAS in patients with migraine and cluster headaches (CH were characterized and compared in a prospective study of consecutive patients attending a headache clinic at Taipei Veterans General Hospital, Taiwan.

  20. Catecholamines and diabetic autonomic neuropathy

    DEFF Research Database (Denmark)

    Hilsted, J

    1995-01-01

    of plasma catecholamine measurements is not due to changes in the clearance of catecholamines in diabetic autonomic neuropathy. The physiological responses to infused adrenaline and to noradrenaline are enhanced, for noradrenaline mainly cardiovascular responses. Adrenoceptors (alpha and beta adrenoceptors...

  1. The Autonomous House: A Bio-Hydrogen Based Energy Self-Sufficient Approach

    Science.gov (United States)

    Chen, Shang-Yuan; Chu, Chen-Yeon; Cheng, Ming-jen; Lin, Chiu-Yue

    2009-01-01

    In the wake of the greenhouse effect and global energy crisis, finding sources of clean, alternative energy and developing everyday life applications have become urgent tasks. This study proposes the development of an “autonomous house” emphasizing the use of modern green energy technology to reduce environmental load, achieve energy autonomy and use energy intelligently in order to create a sustainable, comfortable living environment. The houses’ two attributes are: (1) a self-sufficient energy cycle and (2) autonomous energy control to maintain environmental comfort. The autonomous house thus combines energy-conserving, carbon emission-reducing passive design with active elements needed to maintain a comfortable environment. PMID:19440531

  2. The autonomous house: a bio-hydrogen based energy self-sufficient approach.

    Science.gov (United States)

    Chen, Shang-Yuan; Chu, Chen-Yeon; Cheng, Ming-Jen; Lin, Chiu-Yue

    2009-04-01

    In the wake of the greenhouse effect and global energy crisis, finding sources of clean, alternative energy and developing everyday life applications have become urgent tasks. This study proposes the development of an "autonomous house" emphasizing the use of modern green energy technology to reduce environmental load, achieve energy autonomy and use energy intelligently in order to create a sustainable, comfortable living environment. The houses' two attributes are: (1) a self-sufficient energy cycle and (2) autonomous energy control to maintain environmental comfort. The autonomous house thus combines energy-conserving, carbon emission-reducing passive design with active elements needed to maintain a comfortable environment.

  3. Grassland Sustainability

    Science.gov (United States)

    Deborah U. Potter; Paulette L. Ford

    2004-01-01

    In this chapter we discuss grassland sustainability in the Southwest, grassland management for sustainability, national and local criteria and indicators of sustainable grassland ecosystems, and monitoring for sustainability at various scales. Ecological sustainability is defined as: [T]he maintenance or restoration of the composition, structure, and processes of...

  4. AUTONOMOUS GAUSSIAN DECOMPOSITION

    International Nuclear Information System (INIS)

    Lindner, Robert R.; Vera-Ciro, Carlos; Murray, Claire E.; Stanimirović, Snežana; Babler, Brian; Heiles, Carl; Hennebelle, Patrick; Goss, W. M.; Dickey, John

    2015-01-01

    We present a new algorithm, named Autonomous Gaussian Decomposition (AGD), for automatically decomposing spectra into Gaussian components. AGD uses derivative spectroscopy and machine learning to provide optimized guesses for the number of Gaussian components in the data, and also their locations, widths, and amplitudes. We test AGD and find that it produces results comparable to human-derived solutions on 21 cm absorption spectra from the 21 cm SPectral line Observations of Neutral Gas with the EVLA (21-SPONGE) survey. We use AGD with Monte Carlo methods to derive the H i line completeness as a function of peak optical depth and velocity width for the 21-SPONGE data, and also show that the results of AGD are stable against varying observational noise intensity. The autonomy and computational efficiency of the method over traditional manual Gaussian fits allow for truly unbiased comparisons between observations and simulations, and for the ability to scale up and interpret the very large data volumes from the upcoming Square Kilometer Array and pathfinder telescopes

  5. Is paramecium swimming autonomic?

    Science.gov (United States)

    Bandyopadhyay, Promode R.; Toplosky, Norman; Hansen, Joshua

    2010-11-01

    We seek to explore if the swimming of paramecium has an underlying autonomic mechanism. Such robotic elements may be useful in capturing the disturbance field in an environment in real time. Experimental evidence is emerging that motion control neurons of other animals may be present in paramecium as well. The limit cycle determined using analog simulation of the coupled nonlinear oscillators of olivo-cerebellar dynamics (ieee joe 33, 563-578, 2008) agrees with the tracks of the cilium of a biological paramecium. A 4-motor apparatus has been built that reproduces the kinematics of the cilium motion. The motion of the biological cilium has been analyzed and compared with the results of the finite element modeling of forces on a cilium. The modeling equates applied torque at the base of the cilium with drag, the cilium stiffness being phase dependent. A low friction pendulum apparatus with a multiplicity of electromagnetic actuators is being built for verifying the maps of the attractor basin computed using the olivo-cerebellar dynamics for different initial conditions. Sponsored by ONR 33.

  6. Autonomous Energy Grids: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Kroposki, Benjamin D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Dall-Anese, Emiliano [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bernstein, Andrey [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhang, Yingchen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hodge, Brian S [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-10-04

    With much higher levels of distributed energy resources - variable generation, energy storage, and controllable loads just to mention a few - being deployed into power systems, the data deluge from pervasive metering of energy grids, and the shaping of multi-level ancillary-service markets, current frameworks to monitoring, controlling, and optimizing large-scale energy systems are becoming increasingly inadequate. This position paper outlines the concept of 'Autonomous Energy Grids' (AEGs) - systems that are supported by a scalable, reconfigurable, and self-organizing information and control infrastructure, can be extremely secure and resilient (self-healing), and self-optimize themselves in real-time for economic and reliable performance while systematically integrating energy in all forms. AEGs rely on scalable, self-configuring cellular building blocks that ensure that each 'cell' can self-optimize when isolated from a larger grid as well as partaking in the optimal operation of a larger grid when interconnected. To realize this vision, this paper describes the concepts and key research directions in the broad domains of optimization theory, control theory, big-data analytics, and complex system modeling that will be necessary to realize the AEG vision.

  7. [Autonomic peripheral neuropathy].

    Science.gov (United States)

    Adams, David; Cauquil, Cecile; Lozeron, Pierre

    2012-11-01

    The mechanisms of dysautonomic disturbances are varied and mostly acquired. They can result from lesions of sympathetic or parasympathetic vegetative fibers located in the peripheral contingent, or in the somatic contingent by demyelination or axonal loss; or more rarely by cellular bodies in the sympathetic or parasympathetic ganglia. Several chronic peripheral neuropathies can be associated with dysautonomia. Only some causes need to be known because they can be clinically significant. Dysautonomia may be seen during chronic acquired neuropathies but also acute or subacute ones. The most frequent cause in the world is the dysautonomia of the diabetes; it affects all the systems; the cardiovascular dysfunction has an impact on the prognosis for survival when it is severe. Hereditary autonomic neuropathies are rare; they can declare themselves very early during the Riley-Day syndrome or very late during amyloid polyneuropathies due to transthyretin gene mutation. The diagnosis can be confirmed by molecular biology. The dysautonomia is frequent and often severe. These neuropathies justify symptomatic treatment to improve quality of life. For some of them, a specific treatment can be proposed to treat the causal affection to try to stop the progression of the disease. Copyright © 2012. Published by Elsevier Masson SAS.

  8. AUTONOMOUS GAUSSIAN DECOMPOSITION

    Energy Technology Data Exchange (ETDEWEB)

    Lindner, Robert R.; Vera-Ciro, Carlos; Murray, Claire E.; Stanimirović, Snežana; Babler, Brian [Department of Astronomy, University of Wisconsin, 475 North Charter Street, Madison, WI 53706 (United States); Heiles, Carl [Radio Astronomy Lab, UC Berkeley, 601 Campbell Hall, Berkeley, CA 94720 (United States); Hennebelle, Patrick [Laboratoire AIM, Paris-Saclay, CEA/IRFU/SAp-CNRS-Université Paris Diderot, F-91191 Gif-sur Yvette Cedex (France); Goss, W. M. [National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville, Socorro, NM 87801 (United States); Dickey, John, E-mail: rlindner@astro.wisc.edu [University of Tasmania, School of Maths and Physics, Private Bag 37, Hobart, TAS 7001 (Australia)

    2015-04-15

    We present a new algorithm, named Autonomous Gaussian Decomposition (AGD), for automatically decomposing spectra into Gaussian components. AGD uses derivative spectroscopy and machine learning to provide optimized guesses for the number of Gaussian components in the data, and also their locations, widths, and amplitudes. We test AGD and find that it produces results comparable to human-derived solutions on 21 cm absorption spectra from the 21 cm SPectral line Observations of Neutral Gas with the EVLA (21-SPONGE) survey. We use AGD with Monte Carlo methods to derive the H i line completeness as a function of peak optical depth and velocity width for the 21-SPONGE data, and also show that the results of AGD are stable against varying observational noise intensity. The autonomy and computational efficiency of the method over traditional manual Gaussian fits allow for truly unbiased comparisons between observations and simulations, and for the ability to scale up and interpret the very large data volumes from the upcoming Square Kilometer Array and pathfinder telescopes.

  9. Autonomous power system: Integrated scheduling

    Science.gov (United States)

    Ringer, Mark J.

    1992-01-01

    The Autonomous Power System (APS) project at NASA Lewis Research Center is designed to demonstrate the abilities of integrated intelligent diagnosis, control and scheduling techniques to space power distribution hardware. The project consists of three elements: the Autonomous Power Expert System (APEX) for fault diagnosis, isolation, and recovery (FDIR), the Autonomous Intelligent Power Scheduler (AIPS) to determine system configuration, and power hardware (Brassboard) to simulate a space-based power system. Faults can be introduced into the Brassboard and in turn, be diagnosed and corrected by APEX and AIPS. The Autonomous Intelligent Power Scheduler controls the execution of loads attached to the Brassboard. Each load must be executed in a manner that efficiently utilizes available power and satisfies all load, resource, and temporal constraints. In the case of a fault situation on the Brassboard, AIPS dynamically modifies the existing schedule in order to resume efficient operation conditions. A database is kept of the power demand, temporal modifiers, priority of each load, and the power level of each source. AIPS uses a set of heuristic rules to assign start times and resources to each load based on load and resource constraints. A simple improvement engine based upon these heuristics is also available to improve the schedule efficiency. This paper describes the operation of the Autonomous Intelligent Power Scheduler as a single entity, as well as its integration with APEX and the Brassboard. Future plans are discussed for the growth of the Autonomous Intelligent Power Scheduler.

  10. Autonomous Byte Stream Randomizer

    Science.gov (United States)

    Paloulian, George K.; Woo, Simon S.; Chow, Edward T.

    2013-01-01

    Net-centric networking environments are often faced with limited resources and must utilize bandwidth as efficiently as possible. In networking environments that span wide areas, the data transmission has to be efficient without any redundant or exuberant metadata. The Autonomous Byte Stream Randomizer software provides an extra level of security on top of existing data encryption methods. Randomizing the data s byte stream adds an extra layer to existing data protection methods, thus making it harder for an attacker to decrypt protected data. Based on a generated crypto-graphically secure random seed, a random sequence of numbers is used to intelligently and efficiently swap the organization of bytes in data using the unbiased and memory-efficient in-place Fisher-Yates shuffle method. Swapping bytes and reorganizing the crucial structure of the byte data renders the data file unreadable and leaves the data in a deconstructed state. This deconstruction adds an extra level of security requiring the byte stream to be reconstructed with the random seed in order to be readable. Once the data byte stream has been randomized, the software enables the data to be distributed to N nodes in an environment. Each piece of the data in randomized and distributed form is a separate entity unreadable on its own right, but when combined with all N pieces, is able to be reconstructed back to one. Reconstruction requires possession of the key used for randomizing the bytes, leading to the generation of the same cryptographically secure random sequence of numbers used to randomize the data. This software is a cornerstone capability possessing the ability to generate the same cryptographically secure sequence on different machines and time intervals, thus allowing this software to be used more heavily in net-centric environments where data transfer bandwidth is limited.

  11. The adverse effects of the methoxsalen and ultraviolent A radiation on spermatogenesis in mice

    Directory of Open Access Journals (Sweden)

    Mona Farhadi

    2015-08-01

    Full Text Available Background: Different investigation showed that 5-methoxypsoralen and 8- methoxypsoralen reduce birth rates in the rats. Objective: In this study we worked out the effect of methoxsalen together with ultraviolent A (UVA radiation on mature Balb/C mice spermatogenesis. Materials and Methods: The LD50 standard was determined 160 mg/kg and the UVA dose which causes erythema was calculated 0.046 J/cm2. A sub-lethal dose of 80 mg/kg of methoxsalen solution was injected intrapritoneally to mature mice and after one hour they were exposed to UVA radiation for 20 minutes. Experiments applied included methoxsalen alone, methoxsalen with UVA, UVA alone, sham group (a group received Tween 80, and control group (N=6. In all experimental groups except UVA alone group, injections were carried out, during two consecutive weeks. Serial cross sections (5 µm thickness were prepared for morphological and histological studies. Tunica albuginea diameter, and number of type A and type B spermatogonia and histological investigation of the testes were measured. Results: Microscopical and statistical analyses showed significant anomalies among the experimental groups compared to control and sham group. These anomalies included decrease the body weight; increase the relative testis weight; and decrease the number of spermapogonia (type A and B, primary spermatocytes, spermatids and sperms in experimental groups I and II compared to control group. Our results showed the number of spermatozoa in experimental group I was 22.6±2.12, in experimental group II was 33.6±2.05 and in control group was 44.3±2.77 (p<0.05. Moreover in some experimental groups (I and II shrinkage of seminiferous tubules and release of primary spermatocyte and spermatids were observed to the lumen of them. Conclusion: It is concluded from the results of this work that treatment with methoxsalen with UVA can damage and disorganize seminiferous tubules and decrease spermatogenic cells.

  12. The Effects of Vitex agnus castus Total Extract on Spermatogenesis of Balb/C Mice

    Directory of Open Access Journals (Sweden)

    M Ramezani

    2008-12-01

    Full Text Available ABSTRACT Introduction & Objective: Vitex agnus castus (Verbenaceae is a phytoestrogeic herb native to the Middle East and southern Europe. It has clinical usage in so many countries. In this research, the effects of Vitex agnus castus extract was investigated on spermatogenesis of male Balb/C mice. Materials & Methods: This is an experimental study in which adult male mice were chosen and divided into 3 groups: control, vehicle, and experimental. Animals were daily injected (i.p. with 65, 165 265, 365, and 465 mg/kg of seed extract for ten consecutive days. Then the animals were weighed and eventually killed by cervical dislocation 2 weeks after the last injection. The caudal part of the right epididymis was used for sperm counting. After macroscopic investigation (weight, diameter and volume of testes tissues were fixed in Buin's fixative. Tissues were cut at 5 µm, stained with Hematoxylin and Eosin (H& E.Ccollected data was analyzed by the SPSS software by using one-way ANOVA. Results: No significant differences in body weight, volume, weight and diameter of testes was seen. Light microscopic studies showed a significant reduction in germinal epithelium in doses of 265 and 365 mg/kg and increased of interstitial tissue area in doses of 265, 365, and 465 mg/kg of extract. There was no significant difference in epithelium thickness and of the diameter of the epididymis. Germinal cells contained pyknotic nuclei and several holes that were found scattered in the tubules. Testis also showed a general disarrangement in various germinal elements of seminiferous tubules. Result of sperms count indicated a significant decreasing of spermatozoa in animals which received 265 and 365 mg/kg of extract. Conclusion: Vitex agnus castus contains essential oils, iridoid glycosides, flavonoids diterpenes, and essential fatty acids. The results suggest that its contraceptive effects is related to its flavonoids and essential fatty acids but further studies is

  13. Drosophila Dynein intermediate chain gene, Dic61B, is required for spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Roshan Fatima

    Full Text Available This study reports the identification and characterization of a novel gene, Dic61B, required for male fertility in Drosophila. Complementation mapping of a novel male sterile mutation, ms21, isolated in our lab revealed it to be allelic to CG7051 at 61B1 cytogenetic region, since two piggyBac insertion alleles, CG7051(c05439 and CG7051(f07138 failed to complement. CG7051 putatively encodes a Dynein intermediate chain. All three mutants, ms21, CG7051(c05439 and CG7051(f07138, exhibited absolute recessive male sterility with abnormally coiled sperm axonemes causing faulty sperm individualization as revealed by Phalloidin staining in Don Juan-GFP background. Sequencing of PCR amplicons uncovered two point mutations in ms21 allele and confirmed the piggyBac insertions in CG7051(c05439 and CG7051(f07138 alleles to be in 5'UTR and 4(th exon of CG7051 respectively, excision of which reverted the male sterility. In situ hybridization to polytene chromosomes demonstrated CG7051 to be a single copy gene. RT-PCR of testis RNA revealed defective splicing of the CG7051 transcripts in mutants. Interestingly, expression of cytoplasmic dynein intermediate chain, α, β, γ tubulins and α-spectrin was normal in mutants while ultra structural studies revealed defects in the assembly of sperm axonemes. Bioinformatics further highlighted the homology of CG7051 to axonemal dynein intermediate chain of various organisms, including DNAI1 of humans, mutations in which lead to male sterility due to immotile sperms. Based on these observations we conclude that CG7051 encodes a novel axonemal dynein intermediate chain essential for male fertility in Drosophila and rename it as Dic61B. This is the first axonemal Dic gene of Drosophila to be characterized at molecular level and shown to be required for spermatogenesis.

  14. Differential expression and sex chromosome association of CHD3/4 and CHD5 during spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Judith W Bergs

    Full Text Available ATP-dependent nucleosome remodelers of the CHD family play important roles in chromatin regulation during development and differentiation. The ubiquitously expressed CHD3 and CHD4 proteins are essential for stem cell function and serve to orchestrate gene expression in different developmental settings. By contrast, the closely related CHD5 is predominantly expressed in neural tissue and its role is believed to be restricted to neural differentiation. Indeed, loss of CHD5 contributes to neuroblastoma. In this study, we first demonstrate that CHD5 is a nucleosome-stimulated ATPase. We then compare CHD3/4 and CHD5 expression in mouse brain and show that CHD5 expression is restricted to a subset of cortical and hippocampal neurons whereas CHD3/4 expression is more widespread. We also uncover high levels of CHD5 expression in testis. CHD5 is transiently expressed in differentiating germ cells. Expression is first detected in nuclei of post-meiotic round spermatids, reaches a maximum in stage VIII spermatids and then falls to undetectable levels in stage IX spermatids. Surprisingly, CHD3/4 and CHD5 show complementary expression patterns during spermatogenesis with CHD3/4 levels progressively decreasing as CHD5 expression increases. In spermatocytes, CHD3/4 localizes to the pseudoautosomal region, the X centromeric region and then spreads into the XY body chromatin. In postmeiotic cells, CHD5 colocalises with macroH2A1.2 in association with centromeres and part of the Y chromosome. The subnuclear localisations of CHD4 and CHD5 suggest specific roles in regulation of sex chromosome chromatin and pericentromeric chromatin structure prior to the histone-protamine switch.

  15. Obif, a Transmembrane Protein, Is Required for Bone Mineralization and Spermatogenesis in Mice.

    Directory of Open Access Journals (Sweden)

    Koji Mizuhashi

    Full Text Available Various kinds of transmembrane and secreted proteins play pivotal roles in development through cell-cell communication. We previously reported that Obif (Osteoblast induction factor, Tmem119, encoding a single transmembrane protein, is expressed in differentiating osteoblasts, and that Obif-/- mice exhibit significantly reduced bone volume in the femur. In the current study, we characterized the Obif protein and further investigated the biological phenotypes of a variety of tissues in Obif-/- mice.First, we found that O-glycosylation of the Obif protein occurs at serine residue 36 in the Obif extracellular domain. Next, we observed that Obif-/- mice exhibit bone dysplasia in association with significantly increased osteoid volume per osteoid surface (OV/OS and osteoid maturation time (Omt, and significantly decreased mineral apposition rate (MAR and bone formation rate per bone surface (BFR/BS. In addition, we observed that Obif-/- mice show a significant decrease in testis weight as well as in sperm number. By histological analysis, we found that Obif is expressed in spermatocytes and spermatids in the developing testis and that spermatogenesis is halted at the round spermatid stage in the Obif-/- testis that lacks sperm. However, the number of litters fathered by male mice was slightly reduced in Obif-/- mice compared with wild-type mice, although this was not statistically significant.Our results, taken together with previous observations, indicate that Obif is a type Ia transmembrane protein whose N-terminal region is O-glycosylated. In addition, we found that Obif is required for normal bone mineralization and late testicular differentiation in vivo. These findings suggest that Obif plays essential roles in the development of multiple tissues.

  16. Restoration of spermatogenesis and male fertility using an androgen receptor transgene.

    Directory of Open Access Journals (Sweden)

    William H Walker

    Full Text Available Androgens signal through the androgen receptor (AR to regulate male secondary sexual characteristics, reproductive tract development, prostate function, sperm production, bone and muscle mass as well as body hair growth among other functions. We developed a transgenic mouse model in which endogenous AR expression was replaced by a functionally modified AR transgene. A bacterial artificial chromosome (BAC was constructed containing all AR exons and introns plus 40 kb each of 5' and 3' regulatory sequence. Insertion of an internal ribosome entry site and the EGFP gene 3' to AR allowed co-expression of AR and EGFP. Pronuclear injection of the BAC resulted in six founder mice that displayed EGFP production in appropriate AR expressing tissues. The six founder mice were mated into a Sertoli cell specific AR knockout (SCARKO background in which spermatogenesis is blocked at the meiosis stage of germ cell development. The AR-EGFP transgene was expressed in a cyclical manner similar to that of endogenous AR in Sertoli cells and fertility was restored as offspring were produced in the absence of Sertoli cell AR. Thus, the AR-EGFP transgene under the control of AR regulatory elements is capable of rescuing AR function in a cell selective, AR-null background. These initial studies provide proof of principle that a strategy employing the AR-EGFP transgene can be used to understand AR functions. Transgenic mice expressing selective modifications of the AR-EGFP transgene may provide crucial information needed to elicit the molecular mechanisms by which AR acts in the testis and other androgen responsive tissues.

  17. Ultrastructure of spermatogenesis and mature spermatozoa in the flatworm Prosthiostomum siphunculus (Polycladida, Cotylea).

    Science.gov (United States)

    Gammoudi, Mehrez; Salvenmoser, Willi; Harrath, Abdel Halim; Tekaya, Saïda; Egger, Bernhard

    2016-03-01

    This is the first study investigating spermatogenesis and spermatozoan ultrastructure in the polyclad flatworm Prosthiostomum siphunculus. The testes are numerous and scattered as follicles ventrally between the digestive ramifications. Each follicle contains the different stages of sperm differentiation. Spermatocytes and spermatids derive from a spermatogonium and the spermatids remain connected by intercellular bridges. Chromatoid bodies are present in the cytoplasm of spermatogonia up to spermatids. During early spermiogenesis, a differentiation zone appears in the distal part of spermatids. A ring of microtubules extends along the entire sperm shaft just beneath the cell membrane. An intercentriolar body is present and gives rise to two axonemes, each with a 9 + "1" micro-tubular pattern. Development of the spermatid leads to cell elongation and formation of a filiform, mature spermatozoon with two free flagella and with cortical microtubules along the sperm shaft. The flagella exit the sperm shaft at different levels, a finding common for acotyleans, but so far unique for cotylean polyclads. The Golgi complex produces numerous electron-dense bodies of two types and of different sizes. These bodies are located around a perinuclear row of mitochondria. The elongated nucleus extends almost along the entire sperm body. The nucleus is wide in the proximal part and becomes narrow going towards the distal end. Thread-like chromatin mixed with electron-dense intranuclear spindle-shaped bodies are present throughout nucleus. The general sperm ultrastructure, the presence of intranuclear bodies and a second type of cytoplasmic electron-dense bodies may provide characters useful for phylogenetic analysis. © 2015 The Authors. Cell Biology International published by John Wiley & Sons Ltd on behalf of International Federation of Cell Biology.

  18. Cell polarity, cell adhesion, and spermatogenesis: role of cytoskeletons [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Linxi Li

    2017-08-01

    Full Text Available In the rat testis, studies have shown that cell polarity, in particular spermatid polarity, to support spermatogenesis is conferred by the coordinated efforts of the Par-, Crumbs-, and Scribble-based polarity complexes in the seminiferous epithelium. Furthermore, planar cell polarity (PCP is conferred by PCP proteins such as Van Gogh-like 2 (Vangl2 in the testis. On the other hand, cell junctions at the Sertoli cell–spermatid (steps 8–19 interface are exclusively supported by adhesion protein complexes (for example, α6β1-integrin-laminin-α3,β3,γ3 and nectin-3-afadin at the actin-rich apical ectoplasmic specialization (ES since the apical ES is the only anchoring device in step 8–19 spermatids. For cell junctions at the Sertoli cell–cell interface, they are supported by adhesion complexes at the actin-based basal ES (for example, N-cadherin-β-catenin and nectin-2-afadin, tight junction (occludin-ZO-1 and claudin 11-ZO-1, and gap junction (connexin 43-plakophilin-2 and also intermediate filament-based desmosome (for example, desmoglein-2-desmocollin-2. In short, the testis-specific actin-rich anchoring device known as ES is crucial to support spermatid and Sertoli cell adhesion. Accumulating evidence has shown that the Par-, Crumbs-, and Scribble-based polarity complexes and the PCP Vangl2 are working in concert with actin- or microtubule-based cytoskeletons (or both and these polarity (or PCP protein complexes exert their effects through changes in the organization of the cytoskeletal elements across the seminiferous epithelium of adult rat testes. As such, there is an intimate relationship between cell polarity, cell adhesion, and cytoskeletal function in the testis. Herein, we critically evaluate these recent findings based on studies on different animal models. We also suggest some crucial future studies to be performed.

  19. Fetal cyclophosphamide exposure induces testicular cancer and reduced spermatogenesis and ovarian follicle numbers in mice.

    Directory of Open Access Journals (Sweden)

    Paul B Comish

    Full Text Available Exposure to radiation during fetal development induces testicular germ cell tumors (TGCT and reduces spermatogenesis in mice. However, whether DNA damaging chemotherapeutic agents elicit these effects in mice remains unclear. Among such agents, cyclophosphamide (CP is currently used to treat breast cancer in pregnant women, and the effects of fetal exposure to this drug manifested in the offspring must be better understood to offer such patients suitable counseling. The present study was designed to determine whether fetal exposure to CP induces testicular cancer and/or gonadal toxicity in 129 and in 129.MOLF congenic (L1 mice. Exposure to CP on embryonic days 10.5 and 11.5 dramatically increased TGCT incidence to 28% in offspring of 129 mice (control value, 2% and to 80% in the male offspring of L1 (control value 33%. These increases are similar to those observed in both lines of mice by radiation. In utero exposure to CP also significantly reduced testis weights at 4 weeks of age to ∼ 70% of control and induced atrophic seminiferous tubules in ∼ 30% of the testes. When the in utero CP-exposed 129 mice reached adulthood, there were significant reductions in testicular and epididymal sperm counts to 62% and 70%, respectively, of controls. In female offspring, CP caused the loss of 77% of primordial follicles and increased follicle growth activation. The results indicate that i DNA damage is a common mechanism leading to induction of testicular cancer, ii increased induction of testis cancer by external agents is proportional to the spontaneous incidence due to inherent genetic susceptibility, and iii children exposed to radiation or DNA damaging chemotherapeutic agents in utero may have increased risks of developing testis cancer and having reduced spermatogenic potential or diminished reproductive lifespan.

  20. Compact autonomous navigation system (CANS)

    Science.gov (United States)

    Hao, Y. C.; Ying, L.; Xiong, K.; Cheng, H. Y.; Qiao, G. D.

    2017-11-01

    Autonomous navigation of Satellite and constellation has series of benefits, such as to reduce operation cost and ground station workload, to avoid the event of crises of war and natural disaster, to increase spacecraft autonomy, and so on. Autonomous navigation satellite is independent of ground station support. Many systems are developed for autonomous navigation of satellite in the past 20 years. Along them American MANS (Microcosm Autonomous Navigation System) [1] of Microcosm Inc. and ERADS [2] [3] (Earth Reference Attitude Determination System) of Honeywell Inc. are well known. The systems anticipate a series of good features of autonomous navigation and aim low cost, integrated structure, low power consumption and compact layout. The ERADS is an integrated small 3-axis attitude sensor system with low cost and small volume. It has the Earth center measurement accuracy higher than the common IR sensor because the detected ultraviolet radiation zone of the atmosphere has a brightness gradient larger than that of the IR zone. But the ERADS is still a complex system because it has to eliminate many problems such as making of the sapphire sphere lens, birefringence effect of sapphire, high precision image transfer optical fiber flattener, ultraviolet intensifier noise, and so on. The marginal sphere FOV of the sphere lens of the ERADS is used to star imaging that may be bring some disadvantages., i.e. , the image energy and attitude measurements accuracy may be reduced due to the tilt image acceptance end of the fiber flattener in the FOV. Besides Japan, Germany and Russia developed visible earth sensor for GEO [4] [5]. Do we have a way to develop a cheaper/easier and more accurate autonomous navigation system that can be used to all LEO spacecraft, especially, to LEO small and micro satellites? To return this problem we provide a new type of the system—CANS (Compact Autonomous Navigation System) [6].

  1. Spermatogenesis after extreme hyperthermal, hypothermal and traumatic infl uences and the possibility of its drug correction in the experiment

    Directory of Open Access Journals (Sweden)

    N. V. Avramenko

    2013-12-01

    Full Text Available Introduction Infertility is an important component of the total medical-demographic problems, which accumulates the entire range of factors of socio - economic, behavioral, genetic and natural-climatic, ecological Genesis. Male infertility is founded in 35-40% of the causes of the couple infertility. Attention to the male reproductive function is increasing and it is caused by the appearance of a large number of messages about the increasing incidence of diseases of male reproductive organs, reduction of quantitative and qualitative characteristics of the semen, the significance of the male pathology in the formation of infertility in marriage. Research objective To analyze the status of spermatogenesis after extreme hyperthermal, hypothermal and traumatic effects and the possibility of drug correction in the experiment. Materials and methods Semantic evaluation of scientific documents, comparison, as well as the structural-logical analysis were used. In the literature there are reports of violation of the structure of the sperm. Causes may include testicular injury, surgery or epidemic parotitis (mumps in the past, severe allergic reactions, the impact of radiation, the use of some drugs. Chronic hyperthermia causes changes of all structural components of the tissues of the testicles, which slows down the processes of spermatogenesis. Conclusions There are several reasons for male infertility. Stress, fear of sexual or family relations, in some men are the unwillingness of paternity. Injury or genital mutilation, primarily on the testicles can lead to the violation of the gematotestcular barrier with the formation of specific substances, which destroy tubules of the testicle. Antisperm antibodies completely destroys tubular apparatus. Study of spermatogenesis in experimental models is important and promising direction. It gives both theoretical and practical points of view on the development of methods of prevention and medical correction of

  2. Changes in the expression profile of the meiosis-involved mismatch repair genes in impaired human spermatogenesis.

    Science.gov (United States)

    Terribas, Ernest; Bonache, Sandra; García-Arévalo, Marta; Sánchez, Josvany; Franco, Eladio; Bassas, Lluís; Larriba, Sara

    2010-01-01

    DNA mismatch repair (MMR) genes have been described to participate in crossover events during meiotic recombination, which is, in turn, a key step of spermatogenesis. This evidence suggests that MMR family gene expression may be altered in infertile men with defective sperm production. In order to determine the expression profile of MMR genes in impaired human spermatogenesis, we performed transcript levels analysis of MMR genes (MLH1, MLH3, PMS2, MSH4, and MSH5), and other meiosis-involved genes (ATR, HSPA2, and SYCP3) as controls, by real-time reverse transcription-polymerase chain reaction in testis from 13 patients with spermatogenic failure, 5 patients with primary germ cell tumors, and 10 controls with conserved spermatogenesis. Correlation of the expression values with the histological findings was also performed. The MMR gene expression values, with the exception of PMS2, are significantly decreased in men with spermatogenic failure. The pattern of MMR reduction correlates with the severity of damage, being maximum in maturation arrest. Specifically, expression of the testicular MSH4 gene could be useful as a surrogate marker for the presence of intratesticular elongated spermatid in patients with nonobstructive azoospermia, contributing to predict the viability of assisted reproduction. Interestingly, a reduction in the MSH4 and MSH5 transcript concentration per spermatocyte was also observed. The decreased expression level of other meiosis-specific genes, such as HSPA2 and SYCP3, suggests that the spermatocyte capacity to express meiosis-related genes is markedly reduced in spermatogenic failure, contributing to meiosis impairment and spermatogenic blockade.

  3. Histological analysis and identification of spermatogenesis-related genes in 2-, 6-, and 12-month-old sheep testes

    Science.gov (United States)

    Bai, Man; Sun, Limin; Zhao, Jia; Xiang, Lujie; Cheng, Xiaoyin; Li, Jiarong; Jia, Chao; Jiang, Huaizhi

    2017-10-01

    Testis development and spermatogenesis are vital factors that influence male animal fertility. In order to identify spermatogenesis-related genes and further provide a theory basis for finding biomarkers related to male sheep fertility, 2-, 6-, and 12-month-old Small Tail Han Sheep testes were selected to investigate the dynamic changes of sheep testis development. Hematoxylin-eosin routine staining and RNA-Seq technique were used to perform histological and transcriptome analysis for these testes. The results showed that 630, 102, and 322 differentially expressed genes (DEGs) were identified in 2- vs 6-month-old, 6- vs 12-month-old, and 2- vs 12-month-old testes, respectively. GO and KEGG analysis showed the following: DEGs in 2- vs 6-month-old testes were mainly related to the GO terms of sexual maturation and the pathways of multiple metabolism and biosynthesis; in 6- vs 12-month-old testes, most of the GO terms that DEGs involved in were related to metabolism and translation processes; the most significantly enriched pathway is the ribosome pathway. The union of DEGs in 2- vs 6-month-old, 6- vs 12-month-old, and 2- vs 12-month-old testes was categorized into eight profiles by series cluster. Subsequently, the eight profiles were classified into four model profiles and four co-expression networks were constructed based on the DEGs in these model profiles. Finally, 29 key regulatory genes related to spermatogenesis were identified in the four co-expression networks. The expression of 13 DEGs (CA3, APOH, MYOC, CATSPER4, SYT6, SERPINA10, DAZL, ADIPOR2, RAB13, CEP41, SPAG4, ODF1, and FRG1) was validated by RT-PCR.

  4. Action mechanism of inhibin α-subunit on the development of Sertoli cells and first wave of spermatogenesis in mice.

    Directory of Open Access Journals (Sweden)

    Kailai Cai

    Full Text Available Inhibin is an important marker of Sertoli cell (SC activity in animals with impaired spermatogenesis. However, the precise relationship between inhibin and SC activity is unknown. To investigate this relationship, we partially silenced both the transcription and translation of the gene for the α-subunit of inhibin, Inha, using recombinant pshRNA vectors developed with RNAi-Ready pSIREN-RetroQ-ZsGreen Vector (Clontech Laboratories, Mountain View, Calif. We found that Inha silencing suppresses the cell-cycle regulators Cyclin D1 and Cyclin E and up-regulates the cell-cycle inhibitor P21 (as detected by Western blot analysis, thereby increasing the number of SCs in the G1 phase of the cell cycle and decreasing the amount in the S-phase of the cell cycle (as detected by flow cytometry. Inha silencing also suppressed Pdgfa, Igf1, and Kitl mRNA levels and up-regulated Tgfbrs, Inhba, Inhbb, Cyp11a1, Dhh, and Tjp1 mRNA levels (as indicated by real-time polymerase chain reaction [PCR] analysis. These findings indicate that Inha has the potential to influence the availability of the ligand inhibin and its antagonist activin in the SC in an autocrine manner and inhibit the progression of SC from G1 to S. It may also participate in the development of the blood-testis barrier, Leydig cells, and spermatogenesis through its effect on Dhh, Tjp1, Kitl, and Pdgfa. Real-time PCR and Western blot analyses of Inha, Inhba, and Inhbb mRNA and Inha levels over time show that Inha plays an important role in the formation of round spermatid during the first wave of spermatogenesis in mice.

  5. Tudor-SN Interacts with Piwi Antagonistically in Regulating Spermatogenesis but Synergistically in Silencing Transposons in Drosophila.

    Science.gov (United States)

    Ku, Hsueh-Yen; Gangaraju, Vamsi K; Qi, Hongying; Liu, Na; Lin, Haifan

    2016-01-01

    Piwi proteins associate with piRNAs and functions in epigenetic programming, post-transcriptional regulation, transposon silencing, and germline development. However, it is not known whether the diverse functions of these proteins are molecularly separable. Here we report that Piwi interacts with Tudor-SN (Tudor staphylococcal nuclease, TSN) antagonistically in regulating spermatogenesis but synergistically in silencing transposons. However, it is not required for piRNA biogenesis. TSN is known to participate in diverse molecular functions such as RNAi, degradation of hyper-edited miRNAs, and spliceosome assembly. We show that TSN colocalizes with Piwi in primordial germ cells (PGCs) and embryonic somatic cells. In adult ovaries and testes, TSN is ubiquitously expressed and enriched in the cytoplasm of both germline and somatic cells. The tsn mutants display a higher mitotic index of spermatogonia, accumulation of spermatocytes, defects in meiotic cytokinesis, a decreased number of spermatids, and eventually reduced male fertility. Germline-specific TSN-expression analysis demonstrates that this function is germline-dependent. Different from other known Piwi interters, TSN represses Piwi expression at both protein and mRNA levels. Furthermore, reducing piwi expression in the germline rescues tsn mutant phenotype in a dosage-dependent manner, demonstrating that Piwi and TSN interact antagonistically in germ cells to regulate spermatogenesis. However, the tsn deficiency has little, if any, impact on piRNA biogenesis but displays a synergistic effect with piwi mutants in transposon de-silencing. Our results reveal the biological function of TSN and its contrasting modes of interaction with Piwi in spermatogenesis, transposon silencing, and piRNA biogenesis.

  6. Tudor-SN Interacts with Piwi Antagonistically in Regulating Spermatogenesis but Synergistically in Silencing Transposons in Drosophila.

    Directory of Open Access Journals (Sweden)

    Hsueh-Yen Ku

    2016-01-01

    Full Text Available Piwi proteins associate with piRNAs and functions in epigenetic programming, post-transcriptional regulation, transposon silencing, and germline development. However, it is not known whether the diverse functions of these proteins are molecularly separable. Here we report that Piwi interacts with Tudor-SN (Tudor staphylococcal nuclease, TSN antagonistically in regulating spermatogenesis but synergistically in silencing transposons. However, it is not required for piRNA biogenesis. TSN is known to participate in diverse molecular functions such as RNAi, degradation of hyper-edited miRNAs, and spliceosome assembly. We show that TSN colocalizes with Piwi in primordial germ cells (PGCs and embryonic somatic cells. In adult ovaries and testes, TSN is ubiquitously expressed and enriched in the cytoplasm of both germline and somatic cells. The tsn mutants display a higher mitotic index of spermatogonia, accumulation of spermatocytes, defects in meiotic cytokinesis, a decreased number of spermatids, and eventually reduced male fertility. Germline-specific TSN-expression analysis demonstrates that this function is germline-dependent. Different from other known Piwi interters, TSN represses Piwi expression at both protein and mRNA levels. Furthermore, reducing piwi expression in the germline rescues tsn mutant phenotype in a dosage-dependent manner, demonstrating that Piwi and TSN interact antagonistically in germ cells to regulate spermatogenesis. However, the tsn deficiency has little, if any, impact on piRNA biogenesis but displays a synergistic effect with piwi mutants in transposon de-silencing. Our results reveal the biological function of TSN and its contrasting modes of interaction with Piwi in spermatogenesis, transposon silencing, and piRNA biogenesis.

  7. Effct of Apple Vinegar on Spermatogenesis and Serum Total Antioxidant Status in Rats Under High Fat Diet

    Directory of Open Access Journals (Sweden)

    K.Rudkhaneei

    2016-11-01

    Full Text Available Introduction: Obesity and high fat diet (HFD has side effcts on male fertility. Th aim of this study was to evaluate the effct of apple vinegar on spermatogenesis and serum total antioxidant status (TAS in rats under HFD. Methods: Twenty-four Wistar male rats were divided to three groups, including (n = 8: control, HFD, HFD + apple vinegar. Th control group received 16.6 kcal/day and the other two groups received HFD containing 51.6 kcal/day. Aftr 16 weeks, group 3 received %5 apple vinegar in drinking water orally for six weeks. At the end of the experiment, epididymis sperm parameters including: count, morphology and motility, were measured. Serum level of TAS, testosterone and estradiol was assayed with enzyme linked immunosorbent assay (ELISA. Testicular apoptosis was assayed with terminal deoxynucleotidyl transferase (TdT dUTP nick-end labeling (TUNEL and spermatogenesis was studied with quantitative histologic method. Statistical analysis was performed using analysis of variance (ANOVA and Tukey’s test. Results: Apple vinegar increased count and forward motility of sperms, when compared with HFD (P < 0.05. However, it was not effctive on morphology. Numbers of apoptotic cells reduced in the vinegar-treated group (P < 0.001. Vinegar increased serum levels of testosterone and TAS compared with HFD (P < 0.05. However, estradiol level was not changed. Vinegar reduced the lee index, when compared with HFD (P < 0.001. Th numbers of spermatogonia, primary pachytene and leptotene spermatocyte, and round spermatids were not changed. However, the numbers of elongated spermatids were increased compared with HFD (P < 0.05. Conclusions: Ths study indicated that daily use of apple vinegar in rats under HFD for six weeks improved spermatogenesis through reduction of testis apoptosis, increasing serum TAS and testosterone.

  8. Autonomous Landing on Moving Platforms

    KAUST Repository

    Mendoza Chavez, Gilberto

    2016-08-01

    This thesis investigates autonomous landing of a micro air vehicle (MAV) on a nonstationary ground platform. Unmanned aerial vehicles (UAVs) and micro air vehicles (MAVs) are becoming every day more ubiquitous. Nonetheless, many applications still require specialized human pilots or supervisors. Current research is focusing on augmenting the scope of tasks that these vehicles are able to accomplish autonomously. Precise autonomous landing on moving platforms is essential for self-deployment and recovery of MAVs, but it remains a challenging task for both autonomous and piloted vehicles. Model Predictive Control (MPC) is a widely used and effective scheme to control constrained systems. One of its variants, output-feedback tube-based MPC, ensures robust stability for systems with bounded disturbances under system state reconstruction. This thesis proposes a MAV control strategy based on this variant of MPC to perform rapid and precise autonomous landing on moving targets whose nominal (uncommitted) trajectory and velocity are slowly varying. The proposed approach is demonstrated on an experimental setup.

  9. Occurrence and ultrastructural characterization of "nuage" during oogenesis and early spermatogenesis of Piaractus mesopotamicus Holmberg, 1887 (Teleostei

    Directory of Open Access Journals (Sweden)

    F. C. Abdalla

    Full Text Available We investigated the occurrence and ultrastructurally characterized electrondense nuclear material (nuage released from the nucleus during oogenesis and early spermatogenesis of Piaractus mesopotamicus, a fish from Pantanal Matogrossense (Brazil having a seasonal reproductive cycle. The female germ cells presented two instances of nuclear material extrusion: in the oogonia and in the oocyte in the perinucleolar phase. In males, material with similar morphology and behavior occurred in the spematogonia. In all cases, this material was associated to mitochondria. The possible function of this material is discussed.

  10. Autonomic Function in Neurodegenerative Diseases

    DEFF Research Database (Denmark)

    Sørensen, Gertrud Laura; Jennum, Poul Jørgen

    2013-01-01

    the method by applying standardized methods to measure the autonomic function based on heart rate variability (HRV) measures. 3) Based on the results, assess the validity of autonomic dysfunction as an early marker of a neurodegenerative disease. 4) Evaluate the influence of hypocretin loss in narcolepsy...... areas, which is consistent with the Braak hypothesis. In the narcolepsy patients, it was shown that a reduced HRR to arousals was primarily predicted by hypocretin deficiency in both rapid-eye-movement (REM) and non-REM sleep, independent of cataplexy and other factors. The results confirm...... that hypocretin deficiency affects the autonomic nervous system of patients with narcolepsy and that the hypocretin system is important for proper heart rate modulation at rest.Furthermore, it was shown that hypocretin deficiency and cataplexy are associated with signs of destabilized sleep-wake and REM sleep...

  11. The Bering Autonomous Target Detection

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Denver, Troelz; Betto, Maurizio

    2003-01-01

    An autonomous asteroid target detection and tracking method has been developed. The method features near omnidirectionality and focus on high speed operations and completeness of search of the near space rather than the traditional faint object search methods, employed presently at the larger...... telescopes. The method has proven robust in operation and is well suited for use onboard spacecraft. As development target for the method and the associated instrumentation the asteroid research mission Bering has been used. Onboard a spacecraft, the autonomous detection is centered around the fully...

  12. Political accountability and autonomous weapons

    Directory of Open Access Journals (Sweden)

    James Igoe Walsh

    2015-09-01

    Full Text Available Autonomous weapons would have the capacity to select and attack targets without direct human input. One important objection to the introduction of such weapons is that they will make it more difficult to identify and hold accountable those responsible for undesirable outcomes such as mission failures and civilian casualties. I hypothesize that individuals can modify their attribution of responsibility in predicable ways to accommodate this new technology. The results of a survey experiment are consistent with this; subjects continue to find responsible and hold accountable political and military leaders when autonomous weapons are used, but also attribute responsibility to the designers and programmers of such weapons.

  13. Autonomic Regulation of Splanchnic Circulation

    Directory of Open Access Journals (Sweden)

    Kathleen A Fraser

    1991-01-01

    Full Text Available The role of the autonomic nervous system in circulatory regulation of the splanchnic organs (stomach, small intestine, colon, liver, pancreas and spleen is reviewed. In general, the sympathetic nervous system is primarily involved in vasoconstriction, while the parasympathetic contributes to vasodilation. Vasoconstriction in the splanchnic circulation appears to be mediated by alpha-2 receptors and vasodilation by activation of primary afferent nerves with subsequent release of vasodilatory peptides, or by stimulation of beta-adrenergic receptors. As well, an important function of the autonomic nervous system is to provide a mechanism by which splanchnic vascular reserve can be mobilized during stress to maintain overall cardiovascular homeostasis.

  14. Structural Discrimination and Autonomous Vehicles

    DEFF Research Database (Denmark)

    Liu, Hin-Yan

    2016-01-01

    This paper examines the potential for structural discrimination to be woven into the fabric of autonomous vehicle developments, which remain underexplored and undiscussed. The prospect for structural discrimination arises as a result of the coordinated modes of autonomous vehicle behaviour...... discrimination looms with the possibility of crash optimisation impulses in which a protective shield is cast over those individuals in which society may have a vested interest in prioritising or safeguarding. A stark dystopian scenario is introduced to sketch the contours whereby personal beacons signal...

  15. Sexual characteristics and spermatogenesis in males of the parthenogenetic gecko Lepidodactylus lugubris (Reptilia, Gekkonidae).

    Science.gov (United States)

    Röll, Beate; von Düring, Monika U G

    2008-01-01

    Obligately parthenogenetic lizards usually are all-female populations of hybrids producing diploid oocytes by premeiotic endomitosis and quasi-normal meiosis. In an all-female strain of the gekkonid lizard Lepidodactylus lugubris several phenotypic males arose spontaneously. The sexual characteristics of these males were studied using light and electron microscopy and compared with normal males of the bisexual genus Lygodactylus. Emphasis was layed on morphology of seminiferous tubules, occurrence of spermatogenic stages and ultrastructure of spermatozoa. The phenotypic males possessed preanal pores filled with secretions and a sexual nephric segment which were exactly the same as in normal, reproductively active males. In the testes, density and morphology of non-spermatogenic cell types, the Leydig and Sertoli cells, indicate a normal production of testicular testosterone and a normal function of the blood-testis barrier, respectively. Both in the normal and the phenotypic males, all meiotic cell types of spermatogenesis can be recognised in the seminiferous tubules and are apparently identical, indicating a normal meiosis without impairment in the phenotypic males. In contrast, the differentiation process of spermatids is markedly disturbed in the phenotypic males of L. lugubris. In the normal male, spermiogenesis results in mature spermatids and spermatozoa with small elongated nuclei, an acrosomal complex, and a flagellar tail possessing one axoneme. Spermatozoa fill both the lumen of most seminiferous tubules and the lumina of ductus epididymidis and ductus deferens. In the phenotypic male, spermiogenesis results in seemingly normal spermatids and in spermatozoa with large, non-elongated, deformed nuclei and/or irregular tails possessing more than one axoneme. Both the lumen of most seminiferous tubules and the lumina of the ductus epididymidis and the ductus deferens contain relatively few spermatozoa. We suggest that the phenotypic males inherited the

  16. Leydig cell micronodules are a common finding in testicular biopsies from men with impaired spermatogenesis and are associated with decreased testosterone/LH ratio

    DEFF Research Database (Denmark)

    Holm, Mette; Rajpert-De Meyts, Ewa; Andersson, Anna-Maria

    2003-01-01

    To assess the biological significance of Leydig cell 'hyperplasia' in man, Leydig cell distribution, volume, and function were studied in patients with infertility or testicular cancer and in suddenly deceased controls. A total of 156 biopsies from 95 patients and 18 necropsies from 13 controls....... Leydig cell clusters of more than 15 cells in a cross-section, for which we proposed the name 'micronodules', were frequently seen in testicles exhibiting Sertoli-cell-only syndrome (SCO), a mixed pattern of impaired spermatogenesis, or complete spermatogenesis in combination with elevated FSH. Median...

  17. Protein Arginine Methyltransferase 6 Involved in Germ Cell Viability during Spermatogenesis and Down-Regulated by the Androgen Receptor

    Directory of Open Access Journals (Sweden)

    Manling Luo

    2015-12-01

    Full Text Available Androgens and the androgen receptor (AR are of great importance to spermatogenesis and male fertility. AR knockout (ARKO mice display a complete insensitivity to androgens and male infertility; however, the exact molecular mechanism for this effect remains unclear. In this study, we found that the expression levels of Prmt6 mRNA and protein were significantly up-regulated in the testes of ARKO mice compared to wild type (WT mice. PRMT6 was principally localized to the nucleus of spermatogonia and spermatocytes by immunofluorescence staining. Furthermore, luciferase assay data showed that AR together with testosterone treatment suppressed Prmt6 transcription via binding to the androgen-responsive element (ARE of the Prmt6 promoter. Moreover, knockdown of Prmt6 suppressed germ cells migration and promoted apoptosis. In addition, both of these cellular activities could not be enhanced by testosterone treatment. Taken together, these data indicate that PRMT6, which was down-regulated by AR and influenced cell migration and apoptosis of germ cells, could play a potentially important role in spermatogenesis.

  18. Comparative Study on Histopatological and Histomorphometric Effect of Raw and Cooked Garlic on Spermatogenesis in Testis and Epidydims of Rats

    Directory of Open Access Journals (Sweden)

    khadijeh bahrami

    2014-03-01

    Full Text Available Background &Objective: The present study aims at studying two forms of raw and cooked garlic to identify the effect of this plant on the amount of change in histopatological of spermatogenesis of wistar rat.Materials & Methods: 40 male rats were divided into five equal groups (4 treatment 1 control group the first and second treatment were received palete food consisted of 5% and 15% of raw garlic every day. The third and fourth reatment were received palete food consisted of 5%and 15% of cooked garlic as a food . The control group received standard palete food every day in a month. Finally,the testis were taken out of stomach and after preparing tissue and coloring, they were gone under microscopic studies. Thence, the data were analyzed using SPSS and Duncan test.Results: The study indicated that the amount of sexual cells in the group having cook garlic for 15% compared with that of controlled group had a significant increase and the amount of sexual cells in the group using raw garlic as a food had a significant decrease compared with that of the controlled group.Conclusion: Prescription of cooked garlic has an influence on Proliferation of sexual cells in testicular tubules and epidydymes and so increased spermatogenesis in this group in caparison with the control group. However, prescribing raw garlic has harmful effects on tissue of testis and process of spermatogenes in empric compared with the control group.

  19. Role of stromal derived factor-1a (SDF-1a) for spermatogenesis of busulfan-injured rats.

    Science.gov (United States)

    Khanlarkhani, Neda; Mortezaee, Keywan; Amidi, Fardin; Kharazinejad, Ebrahim; Beyer, Cordian; Baazm, Maryam; Pasbakhsh, Parichehr; Pazhohan, Azar; Sobhani, Aligholi; Zendedel, Adib

    2017-10-01

    SDF-1a is a member of CXC chemokine family that plays a crucial role in stem cell migration, cell apoptosis and development. The role of intra-scrotal administration of SDF-1a in spermatogenesis of busulfan-treated rats was investigated in this study. Two injections of busulfan (15mg/kg) with a 14days interval between were given intraperitoneally to male Wistar rats. Rats were then treated for seven days with 500ng/mL SDF-1a. Real-time PCR and immunohistochemistry were performed for evaluation of various cell markers for proliferation and spermatogenesis, and sperm parameters were assessed. In the SDF-1a group, there was a significant increase in testis weight, sperm count and viability. DAZL, DDX4, and TP2 showed increased expression levels in the SDF-1a group. PCNA and BrdU revealed highest expression rates in the SDF-1a group (p≤0.0001). These findings showed the protective role of SDF-1a in busulfan-induced testis injury most likely through stimulation of SSCs proliferation. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Effect of Electromagnetic Waves from Mobile Phones on Spermatogenesis in the Era of 4G-LTE

    Directory of Open Access Journals (Sweden)

    Jong Jin Oh

    2018-01-01

    Full Text Available Objective. To investigate the effect of long duration exposure to electromagnetic field from mobile phones on spermatogenesis in rats using 4G-LTE. Methods. Twenty Sprague-Dawley male rats were placed into 4 groups according to the intensity and exposure duration: Group 1 (sham procedure, Group 2 (3 cm distance + 6 h exposure daily, Group 3 (10 cm distance + 18 h exposure daily, and Group 4 (3 cm distance + 18 h exposure daily. After 1 month, we compared sperm parameters and histopathological findings of the testis. Results. The mean spermatid count (×106/ml was 398.6 in Group 1, 365.40 in Group 2, 354.60 in Group 3, and 298.60 in Group 4 (p=0.041. In the second review, the mean count of spermatogonia in Group 4 (43.00 was significantly lower than in Group 1 (57.00 and Group 2 (53.40 (p<0.001 and p=0.010, resp.. The sum of the germ cell counts was decreased in Group 4 compared to Groups 1, 2, and 3 (p=0.032. The mean Leydig cell count was significantly decreased in Group 4 (p<0.001. Conclusions. The longer exposure duration of electromagnetic field decreased the spermatogenesis. Our findings warrant further investigations on the potential effects of EMF from mobile phones on male fertility.

  1. Increasing viability, numbers, and motility of sperm in men with normal spermatogenesis exposed to saffron extract after freezing- thawing process

    Directory of Open Access Journals (Sweden)

    Y. Khazaei

    2017-04-01

    Full Text Available Background: Sperm freezing method is used frequently in assisted reproductive techniques, on the other hand in different studies negative effect of freezing have been shown on different sperm parameters. Objective: The aim of this study was to determine the effect of saffron extract as an antioxidant, on the different sperm parameters in men with normal spermatogenesis after freezing-thawing process. Methods: In this case-control study, collecting of samples was done in 2015 year from the Infertility Treatment Center, ACECR Branch of Qazvin, Qazvin, Iran. These men had normal spermatogenesis and their spouse had infertility problem. Semen samples was divided in two groups, control without saffron extract, and case with 50 mg/ml saffron extract. Then, samples freezed with snap freezing method. After two weeks, they were thawed and different sperm parameters were assessed. Data were analyzed by two-tail T test. Findings: Our results showed, mean percent of viability (72±0.99, motility (87±0.43, and the number of sperm cells (62.5±3.8 in treaded group was elevated significantly (P0.05. Conclusion: Our results showed that possibly antioxidant agents of saffron extract could scavenge free radicals and thus, optimize different sperm parameters (viability, motility, and number after freezing and thawing.

  2. Enhanced fat consumption potentiates acrylamide-induced oxidative stress in epididymis and epididymal sperm and effect spermatogenesis in mice.

    Science.gov (United States)

    Zhang, J X; Yue, W B; Ren, Y S; Zhang, C X

    2010-02-01

    Acrylamide (ACR) and high contents of fat could be found co-existent in many foods processed by high temperature, such as deep-frying and roasting. This study investigated the effect of enhanced fat consumption on deficits of spermatogenesis induced by ACR, and explored potential mechanisms of oxidative damage involved in this pathology in mice. Results show that enhanced feeding of corn oil and pork fat on mice potentiated the decreases of spermatogonia along with mature sperms after treatment of ACR, and that spermatozoa quality is significantly reduced as a result of enhanced feeding of corn oil and pork fat on mice treated with ACR. Moreover, enhanced consumption of corn oil and pork fat potentiated the up-regulation of malondialdehyde (MDA) level in epididymal sperm and cauda epididymides, also up-regulated level of Protein carbonyls (PCOs) in cauda epididymides, of mice after treatment of ACR. Last, enhanced consumption of corn oil and pork fat potentiated the reduced activity of superoxide dismutases (SOD) in epididymal sperm, corpus, and cauda epididymides, also reduced activity of glutathione peroxidase (GPx) in cauda epididymides, of mice treated with ACR. These data suggest that enhanced feeding of corn oil and pork fat on mice potentiates ACR-induced oxidative stress in the epididymis and epididymal sperm and a subsequent effect on spermatogenesis.

  3. Connected and autonomous vehicles 2040 vision.

    Science.gov (United States)

    2014-07-01

    The Pennsylvania Department of Transportation (PennDOT) commissioned a one-year project, Connected and Autonomous : Vehicles 2040 Vision, with researchers at Carnegie Mellon University (CMU) to assess the implications of connected and : autonomous ve...

  4. Energy homeostasis, autonomic activity and obesity

    NARCIS (Netherlands)

    Scheurink, AJW; Balkan, B; Nyakas, C; vanDijk, G; Steffens, AB; Bohus, B

    1995-01-01

    Obesity is often accompanied by alterations in both sympathetic and parasympathetic autonomic functions. The present paper summarizes the results of a number of studies designed to investigate autonomic functioning in normal, genetically, and experimentally obese rats, Particular emphasis is given

  5. Congenital combined pituitary hormone deficiency patients have better responses to gonadotrophin-induced spermatogenesis than idiopathic hypogonadotropic hypogonadism patients.

    Science.gov (United States)

    Mao, Jiangfeng; Xu, Hongli; Wang, Xi; Huang, Bingkun; Liu, Zhaoxiang; Zhen, Junjie; Nie, Min; Min, Le; Wu, Xueyan

    2015-09-01

    Do patients with congenital combined pituitary hormone deficiency (CCPHD) have different responses to gonadotrophin-induced spermatogenesis compared with those with idiopathic hypogonadotropic hypogonadism (IHH)? CCPHD patients have a better response to gonadotrophin therapy than IHH patients. Gonadotrophins are effective in inducing spermatogenesis in patients with hypogonadotropic hypogonadism. This retrospective cohort study included 75 patients, 53 of whom had IHH and 22 CCPHD. They were diagnosed, treated and followed up between January 2008 and December 2013. Combined gonadotrophin therapy, consisting of human chorionic gonadotrophin and human menopausal gonadotrophin, was administered for 24 months. The success rate of spermatogenesis (≥1 sperm in ejaculate), serum total testosterone level, testicle size and sperm concentration during the treatment, as well as the first time sperm were detected in the ejaculate, were compared between the two diagnostic groups. All patients were treated in Peking Union Medical College Hospital. Spermatogenesis was successfully induced in 85% of IHH patients and 100% of CCPHD patients after 24-month combined gonadotrophin treatment (P = 0.03). In comparison with IHH, CCPHD patients had larger mean testicle sizes during the gonadotrophin treatment at 6, 12, 18 and 24 months (all P < 0.05). The initial time for sperm appearance in IHH group (n = 45) and CCPHD group (n = 22) was 13.2 ± 5.9 versus 10.4 ± 3.8 months (P = 0.045). Generally, CCPHD patients had higher sperm counts [median (quartiles)] than IHH patients during the treatment, but the difference was only statistically significant at 12 months of treatment, 3.3 (1.8, 12.0) versus 1.0 (0.0, 4.6) million/ml, P = 0.001. There was a higher level of serum total testosterone [mean (SD)] in the CCPHD group than the IHH group (676 ± 245 versus 555 ± 209 ng/dl, P = 0.035). First, the inherent nature of a retrospective designed study was a main shortcoming. Secondly

  6. Study of comparison between autonomic dysfunction and dyslipidemia in healthy postmenopausal women

    Directory of Open Access Journals (Sweden)

    Kavyach Yalamudi

    2017-01-01

    Full Text Available Background: Obesity, physical inactivity, and altered estrogen levels play an important role in contributing to disease risk profile and autonomic dysfunction in healthy postmenopausal women. This study was conducted to test the correlation between autonomic dysfunction and dyslipidemia in healthy postmenopausal women. Materials and Methods: This study was carried out on sixty healthy postmenopausal women before the age of 65 years, without any gross systemic disease. The following five autonomic functional tests were performed on the study group: heart rate response to deep breathing, heart rate response to Valsalva maneuver, heart rate response to standing up from supine position, blood pressure response to sustained hand grip, and blood pressure response to standing up from supine position. Fasting lipid profile of the study group was tested. Results and Conclusion: In the present study, autonomic dysfunction was found in 67% of healthy postmenopausal women. Among the sixty female healthy postmenopausal women included in the study, 68% were found to have dyslipidemia. In our study, there is a statistically significant correlation between autonomic dysfunction and dyslipidemia in healthy postmenopausal women. In these healthy postmenopausal women with increased serum cholesterol, serum low-density lipoprotein, and serum triglycerides, there was autonomic dysfunction which is statistically significant. There is no statistical significance on comparing serum high-density lipoprotein cholesterol with autonomic dysfunction in healthy postmenopausal women.

  7. Research and development of Ro-boat: an autonomous river cleaning robot

    Science.gov (United States)

    Sinha, Aakash; Bhardwaj, Prashant; Vaibhav, Bipul; Mohommad, Noor

    2013-12-01

    Ro-Boat is an autonomous river cleaning intelligent robot incorporating mechanical design and computer vision algorithm to achieve autonomous river cleaning and provide a sustainable environment. Ro-boat is designed in a modular fashion with design details such as mechanical structural design, hydrodynamic design and vibrational analysis. It is incorporated with a stable mechanical system with air and water propulsion, robotic arms and solar energy source and it is proceed to become autonomous by using computer vision. Both "HSV Color Space" and "SURF" are proposed to use for measurements in Kalman Filter resulting in extremely robust pollutant tracking. The system has been tested with successful results in the Yamuna River in New Delhi. We foresee that a system of Ro-boats working autonomously 24x7 can clean a major river in a city on about six months time, which is unmatched by alternative methods of river cleaning.

  8. Autonomic Dysfunction and Risk Factors Associated with Trypanosoma cruzi Infection among Children in Arequipa, Peru

    Science.gov (United States)

    Bowman, Natalie M.; Kawai, Vivian; Gilman, Robert H.; Bocangel, Cesar; Galdos-Cardenas, Gerson; Cabrera, Lilia; Levy, Michael Z.; Cornejo del Carpio, Juan Geny; Delgado, Freddy; Rosenthal, Lauren; Pinedo-Cancino, Vivian V.; Steurer, Francis; Seitz, Amy E.; Maguire, James H.; Bern, Caryn

    2011-01-01

    Chagas disease affects an estimated 8 million people in Latin America. Infected individuals have 20–30% lifetime risk of developing cardiomyopathy, but more subtle changes in autonomic responses may be more frequent. We conducted a matched case-control study of children in Arequipa, Peru, where triatomine infestation and Trypanosoma cruzi infection are emerging problems. We collected data on home environment, history, physical examination, electrocardiogram, and autonomic testing. Signs of triatomine infestation and/or animals sleeping in the child's room and household members with Chagas disease were associated with increased infection risk. Electrocardiogram findings did not differ between cases and controls. However, compared with control children, infected children had blunted autonomic responses by three different measures, the Valsalva maneuver, the cold pressor test, and the orthostatic test. T. cruzi-infected children show autonomic dysfunction, although the prognostic value of this finding is not clear. Sustained vector control programs are essential to decreasing future T. cruzi infections. PMID:21212207

  9. Evaluating Autonomous Ground-Robots

    Science.gov (United States)

    2012-06-14

    Evaluating Autonomous Ground-Robots 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Anthony Finn; Adam Jacoff; Mike...these metrics against the detailed choreography of the challenge to prevent teams ‘gaming’ the result (i.e. devising technical solutions that were

  10. Hazard Map for Autonomous Navigation

    DEFF Research Database (Denmark)

    Riis, Troels

    This dissertation describes the work performed in the area of using image analysis in the process of landing a spacecraft autonomously and safely on the surface of the Moon. This is suggested to be done using a Hazard Map. The correspondence problem between several Hazard Maps are investigated...

  11. Computing architecture for autonomous microgrids

    Science.gov (United States)

    Goldsmith, Steven Y.

    2015-09-29

    A computing architecture that facilitates autonomously controlling operations of a microgrid is described herein. A microgrid network includes numerous computing devices that execute intelligent agents, each of which is assigned to a particular entity (load, source, storage device, or switch) in the microgrid. The intelligent agents can execute in accordance with predefined protocols to collectively perform computations that facilitate uninterrupted control of the .

  12. Autonomous Duffing-Holmes Type Chaotic Oscillator

    DEFF Research Database (Denmark)

    Tamaševičius, A.; Bumelienė, S.; Kirvaitis, R.

    2009-01-01

    We have designed and built a novel Duffing type autonomous 3rd-order chaotic oscillator. In comparison with the common non-autonomous DuffingHolmes type oscillator the autonomous circuit has an internal positive feedback loop instead of an external periodic drive source. In addition...

  13. CAAD: Computer Architecture for Autonomous Driving

    OpenAIRE

    Liu, Shaoshan; Tang, Jie; Zhang, Zhe; Gaudiot, Jean-Luc

    2017-01-01

    We describe the computing tasks involved in autonomous driving, examine existing autonomous driving computing platform implementations. To enable autonomous driving, the computing stack needs to simultaneously provide high performance, low power consumption, and low thermal dissipation, at low cost. We discuss possible approaches to design computing platforms that will meet these needs.

  14. The treatment of autonomic dysfunction in tetanus

    African Journals Online (AJOL)

    may either be spontaneous or triggered by touch, visual, auditory or emotional stimuli.[7] Autonomic dysfunction may occur, and does not necessarily correlate with the severity of tetanus. Wassay et al.[8] reported autonomic dysfunction in a third of tetanus cases. Autonomic dysfunction presents as labile hypertension, ...

  15. Sustainable Transportation

    DEFF Research Database (Denmark)

    Hall, Ralph P.; Gudmundsson, Henrik; Marsden, Greg

    2014-01-01

    that relate to the construction and maintenance of transportation infrastructure and the operation or use of the different transportation modes. The concept of sustainable transportation emerged in response to these concerns as part of the broader notion of sustainable development. Given the transportation...... sector’s significant contribution to global challenges such as climate change, it is often said that sustainable development cannot be achieved without sustainable transportation....

  16. Sustainable Marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2017-01-01

    In this article, three different conceptions of sustainable marketing are discussed and compared. These different conceptions are referred to as social, green, and critical sustainable marketing. Social sustainable marketing follows the logic of demand-driven marketing management and places the

  17. Multiple Distributed Smart Microgrids with a Self-Autonomous, Energy Harvesting Wireless Sensor Network

    DEFF Research Database (Denmark)

    Guerrero, Josep M.; Kheng Tan, Yen

    2012-01-01

    The chapter covers the smart wireless sensors for microgrids, as well as the energy harvesting technology used to sustain the operations of these sensors. Last, a case study on the multiple distributed smart microgrids with a self-autonomous, energy harvesting wireless sensor network is presented....

  18. More with thermal energy storage. Report 8. Autonomous heating. Autonomous development of ground temperature. Final report; Meer met bodemenergie. Rapport 8. Autonome opwarming. Autonome ontwikkeling bodemtemperatuur. Eindrapport

    Energy Technology Data Exchange (ETDEWEB)

    Drijver, B. [IF Technology, Arnhem (Netherlands)

    2012-03-30

    The project More With Thermal Energy Storage (MMB, abbreviated in Dutch) focuses on knowledge gaps and potential opportunities regarding open systems. The main questions to be answered are: (1) What effects (hydrological, thermal, microbiological and chemical) occur in the soil system by application of thermal energy storage; (2) Which technical options are available for a sustainable integration of thermal energy storage in the water and energy chain?; (3) Is it possible to achieve multiple objectives by using smart combinations? The project is organized in different work packages. In work package 2, the effects of individual and collective thermal energy storage storage systems on subsoils and the environment are determined. In work package 3 the opportunities for thermal energy storage and soil remediation are examined, while in work package 4 the focus is on new sustainable combinations of heat and cold storage. Work package 1 is the umbrella part where communication and policy of and participation in MMB are the main subjects. This report contains an analysis of the thermal impact of climate change and urbanization on the soil temperature. Attention is paid to the autonomous heating of the subsurface that occurred since 1900 and that still may be expected up to 2040. A distinction is made between rural areas, where only the climate change plays a role, and urban areas, where the UHI effect (Urban Heat Island) is of importance [Dutch] Het project Meer Met Bodemenergie (MMB) richt zich op het invullen van kennisleemtes en mogelijke kansen ten aanzien van open systemen. De belangrijkste vragen waarop het onderzoeksprogramma MMB antwoord geeft zijn: (1) Welke effecten (hydrologisch, thermisch, microbiologisch en chemisch) treden op in het bodemsysteem bij toepassing van bodemenergie?; (2) Welke technische mogelijkheden zijn er voor het duurzaam inpassen van bodem-energie in de water- en energieketen?; (3) Is het mogelijk om meerdere doelstellingen tegelijk te

  19. Autonomous Cryogenics Loading Operations Simulation Software: Knowledgebase Autonomous Test Engineer

    Science.gov (United States)

    Wehner, Walter S., Jr.

    2013-01-01

    Working on the ACLO (Autonomous Cryogenics Loading Operations) project I have had the opportunity to add functionality to the physics simulation software known as KATE (Knowledgebase Autonomous Test Engineer), create a new application allowing WYSIWYG (what-you-see-is-what-you-get) creation of KATE schematic files and begin a preliminary design and implementation of a new subsystem that will provide vision services on the IHM (Integrated Health Management) bus. The functionality I added to KATE over the past few months includes a dynamic visual representation of the fluid height in a pipe based on number of gallons of fluid in the pipe and implementing the IHM bus connection within KATE. I also fixed a broken feature in the system called the Browser Display, implemented many bug fixes and made changes to the GUI (Graphical User Interface).

  20. Autonomic computing enabled cooperative networked design

    CERN Document Server

    Wodczak, Michal

    2014-01-01

    This book introduces the concept of autonomic computing driven cooperative networked system design from an architectural perspective. As such it leverages and capitalises on the relevant advancements in both the realms of autonomic computing and networking by welding them closely together. In particular, a multi-faceted Autonomic Cooperative System Architectural Model is defined which incorporates the notion of Autonomic Cooperative Behaviour being orchestrated by the Autonomic Cooperative Networking Protocol of a cross-layer nature. The overall proposed solution not only advocates for the inc

  1. Human-specific subcellular compartmentalization of P-element induced wimpy testis-like (PIWIL) granules during germ cell development and spermatogenesis

    NARCIS (Netherlands)

    Gomes Fernandes, Maria; He, Nannan; Wang, Fang; Van Iperen, Liesbeth; Eguizabal, Cristina; Matorras, Roberto; Roelen, Bernard A J; Chuva de Sousa Lopes, Susana M

    2018-01-01

    STUDY QUESTION: What is the dynamics of expression of P-element induced wimpy testis-like (PIWIL) proteins in the germline during human fetal development and spermatogenesis? SUMMARY ANSWER: PIWIL1, PIWIL2, PIWIL3 and PIWIL4 were expressed in a sex-specific fashion in human germ cells (GC) during

  2. Morphologic Changes in Autonomic Nerves in Diabetic Autonomic Neuropathy

    Directory of Open Access Journals (Sweden)

    Heung Yong Jin

    2015-12-01

    Full Text Available Diabetic neuropathy is one of the major complications of diabetes, and it increases morbidity and mortality in patients with both type 1 diabetes mellitus (T1DM and type 2 diabetes mellitus (T2DM. Because the autonomic nervous system, for example, parasympathetic axons, has a diffuse and wide distribution, we do not know the morphological changes that occur in autonomic neural control and their exact mechanisms in diabetic patients with diabetic autonomic neuropathy (DAN. Although the prevalence of sympathetic and parasympathetic neuropathy is similar in T1DM versus T2DM patients, sympathetic nerve function correlates with parasympathetic neuropathy only in T1DM patients. The explanation for these discrepancies might be that parasympathetic nerve function was more severely affected among T2DM patients. As parasympathetic nerve damage seems to be more advanced than sympathetic nerve damage, it might be that parasympathetic neuropathy precedes sympathetic neuropathy in T2DM, which was Ewing's concept. This could be explained by the intrinsic morphologic difference. Therefore, the morphological changes in the sympathetic and parasympathetic nerves of involved organs in T1DM and T2DM patients who have DAN should be evaluated. In this review, evaluation methods for morphological changes in the epidermal nerves of skin, and the intrinsic nerves of the stomach will be discussed.

  3. Insights into the background of autonomic medicine.

    Science.gov (United States)

    Laranjo, Sérgio; Geraldes, Vera; Oliveira, Mário; Rocha, Isabel

    2017-10-01

    Knowledge of the physiology underlying the autonomic nervous system is pivotal for understanding autonomic dysfunction in clinical practice. Autonomic dysfunction may result from primary modifications of the autonomic nervous system or be secondary to a wide range of diseases that cause severe morbidity and mortality. Together with a detailed history and physical examination, laboratory assessment of autonomic function is essential for the analysis of various clinical conditions and the establishment of effective, personalized and precise therapeutic schemes. This review summarizes the main aspects of autonomic medicine that constitute the background of cardiovascular autonomic dysfunction. Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Chemoablated mouse seminiferous tubular cells enriched for very small embryonic-like stem cells undergo spontaneous spermatogenesis in vitro.

    Science.gov (United States)

    Anand, Sandhya; Patel, Hiren; Bhartiya, Deepa

    2015-04-18

    Extensive research is ongoing to empower cancer survivors to have biological parenthood. For this, sperm are cryopreserved prior to therapy and in younger children testicular biopsies are cryopreserved with a hope to mature the germ cells into sperm later on for assisted reproduction. In addition, lot of hope was bestowed on pluripotent embryonic and induced pluripotent stem cells to differentiate into sperm and oocytes. However, obtaining functional gametes from pluripotent stem cells still remains a distant dream and major bottle-neck appears to be their inefficient differentiation into primordial germ cells (PGCs). There exists yet another population of pluripotent stem cells termed very small embryonic-like stem cells (VSELs) in adult body organs including gonads. We have earlier reported that busulphan (25 mg/Kg) treatment to 4 weeks old mice destroys actively dividing cells and sperm but VSELs survive and differentiate into sperm when a healthy niche is provided in vivo. Mouse testicular VSELs that survived busulphan treatment were cultured for 3 weeks. A mix of surviving cells in seminiferous tubules (VSELs, possibly few spermatogonial stem cells and Sertoli cells) were cultured using Sertoli cells conditioned medium containing fetal bovine serum, follicle stimulating hormone and with no additional growth factors. Stem cells underwent proliferation and clonal expansion in culture and spontaneously differentiated into sperm whereas Sertoli cells attached and provided a somatic support. Transcripts specific for various stages of spermatogenesis were up-regulated by qRT-PCR studies on day 7 suggesting VSELs (Sca1) and SSCs (Gfra) proliferate (Pcna), undergo spermatogenesis (spermatocyte specific marker prohibitin), meiosis (Scp3) and differentiate into sperm (post-meiotic marker protamine). Process of spermatogenesis and spermiogenesis was replicated in vitro starting with testicular cells that survived busulphan treatment. We have earlier reported similar

  5. Research Update: Nanogenerators for self-powered autonomous wireless sensors

    Science.gov (United States)

    Khan, Usman; Hinchet, Ronan; Ryu, Hanjun; Kim, Sang-Woo

    2017-07-01

    Largely distributed networks of sensors based on the small electronics have great potential for health care, safety, and environmental monitoring. However, in order to have a maintenance free and sustainable operation, such wireless sensors have to be self-powered. Among various energies present in our environment, mechanical energy is widespread and can be harvested for powering the sensors. Piezoelectric and triboelectric nanogenerators (NGs) have been recently introduced for mechanical energy harvesting. Here we introduce the architecture and operational modes of self-powered autonomous wireless sensors. Thereafter, we review the piezoelectric and triboelectric NGs focusing on their working mechanism, structures, strategies, and materials.

  6. Autonomous Agents as Artistic Collaborators

    DEFF Research Database (Denmark)

    Kadish, David

    In this paper, I ask whether it is possible to exert creative direction on the emergence of large scale patterns from the actions of autonomous or semi-autonomous actors. As an artist and an engineer, I undertake installations and projects with an intent to create, to make art or innovative...... structures. At the same time, one of my artistic interests is in ceding a great deal of creative control to a cluster of robotic actors, in the process interrogating the lack of control that we, as a species, exert over the world. Here, I explore this idea in the context of an ongoing project called...... which innovations at large (galactic systems) and small (DNA) scales emerged were happy accidents of physics and chemistry. This raises the fundamental questions that my work explores, interrogating the relationship between the creativity of emergent processes on the micro- and macro- scales...

  7. Health, autonomic financing and transferences

    Directory of Open Access Journals (Sweden)

    David Cantarero Prieto

    2002-01-01

    Full Text Available The present paper has as objective to study the whole relative problem to the autonomous communities and regional heath care expenditure financing in Spain. This article has a dual purpose. First, the financing of the current health care attendance is approached in the Spanish regions passing magazine to its possible variants and we observe that the balance of our system is clearly inclined towards the side of the integration in the general pattern of financing («Fiscal Room» with specific conditions («Mixed System». Secondly, we examine the new situation in the mark of health care and its corresponding financing in the new model approved in 2001, in terms of the effects of tax assignment on autonomous communities.

  8. Autonomously managed high power systems

    International Nuclear Information System (INIS)

    Weeks, D.J.; Bechtel, R.T.

    1985-01-01

    The need for autonomous power management capabilities will increase as the power levels of spacecraft increase into the multi-100 kW range. The quantity of labor intensive ground and crew support consumed by the 9 kW Skylab cannot be afforded in support of a 75-300 kW Space Station or high power earth orbital and interplanetary spacecraft. Marshall Space Flight Center is managing a program to develop necessary technologies for high power system autonomous management. To date a reference electrical power system and automation approaches have been defined. A test facility for evaluation and verification of management algorithms and hardware has been designed with the first of the three power channel capability nearing completion

  9. Effects of microwave oven exposed diet on spermatogenesis in testicular tissue of mice and comparative effects of mentha piperita and melatonin

    International Nuclear Information System (INIS)

    Naheed, K.; Qamar, K.; Jamal, S.

    2017-01-01

    Objective: To observe the effects of microwave oven exposed diet on spermatogenesis in the testis of mice and comparative effects of Mentha piperita and melatonin. Study Design: Laboratory based randomized controlled trial. Place and Duration of Study: Anatomy Department, Army Medical College Rawalpindi, in collaboration with National Institute of Health (NIH), Islamabad, from Apr 2015 to May 2015. Material and Method: Study comprised of 32 adult male mice (BALBc strain) weighing 25-30 gms. Selection criteria based on non-probability (purposive) simple random sampling. Mice were divided into four equal groups of 8 mice each. Group 1, taken as control, was given standard diet 5-10gm/animal/day daily for four weeks. Group 2 was given 5-10 gm/animal/day of microwave oven exposed mice pellets for four weeks. Group 3 received Mentha piperita leaf extract (1g/kg b.wt./day) along with microwave oven exposed mice pellets (5-10gm/animal/day) for 4 weeks and group 4 received oral dosage of melatonin 12mg/kg/day along with microwave oven exposed mice pellets (5-10gm/animal/day) for 4 weeks. After four weeks animals were dissected. The shape, color and any abnormal finding of the testis were observed. Testis were processed, embedded and stained for histological study. Spermatogenesis was assessed by the Johnsons scoring. SPSS 21 was used for statistical analysis. Chi square test was applied for intergroup comparison. Results: Spermatogenesis was suppressed and Johnsons score was decreased from normal spermatogenesis (10) to (6-8) in the experimental group 2 and was more improved in the Mentha piperita treated group as compare to the melatonin. Conclusion: Microwave oven exposed mice pellets suppressed spermatogenesis and Mentha piperita had better ameliorative effects than melatonin on the testis of mice. (author)

  10. Effects of lead, molybdenum, rubidium, arsenic and organochlorines on spermatogenesis in fish: Monitoring at Mekong Delta area and in vitro experiment

    International Nuclear Information System (INIS)

    Yamaguchi, Sonoko; Miura, Chiemi; Ito, Aki; Agusa, Tetsuro; Iwata, Hisato; Tanabe, Shinsuke; Bui Cach Tuyen; Miura, Takeshi

    2007-01-01

    To estimate the influence of water contaminants on fish reproduction in the Mekong Delta area, we sampled cultivated male catfish (Pangasianodon hypophthalmus), investigated testicular development, and measured persistent organic pollutants (POPs) and trace element levels in muscle and liver, respectively. Various testes sizes were observed although sampling took place during a short period. Histological analysis revealed that all developmental stages of germ cells were observed in catfish with large testis, whereas only necrotic spermatogonia but no other germ cells were observed in catfish with small testis. In small testis, furthermore, vacuolization and hypertrophy of Sertoli cells were observed. Measurement of POPs in muscle and trace elements in liver demonstrated that there were negative correlations between GSI and the concentrations of Pb, Mo, Rb and As. To clarify possible direct effects of Pb, Mo, Rb and As on spermatogenesis in fish, we investigated the effects of these trace elements on spermatogenesis using in vitro testicular organ culture of Japanese eel (Anguilla japonica). Treatment with each of the trace elements alone did not affect spermatogenesis. However, treatment with 10 -7 M of Pb, 10 -5 and 10 -4 M of Mo, 10 -5 -10 -3 M of Rb or 10 -5 M of As inhibited the spermatogenesis induced by 11-ketotestosterone (11KT). Furthermore, treatment with 10 -4 M of As in combination with 11KT caused necrosis of testicular fragments. Taken together, these results are consistent with the hypothesis that Pb, Mo, Rb and As can exert inhibitory effects on spermatogenesis in catfish inhabiting the Mekong Delta area

  11. Effects of lead, molybdenum, rubidium, arsenic and organochlorines on spermatogenesis in fish: Monitoring at Mekong Delta area and in vitro experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Sonoko [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Miura, Chiemi [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Ito, Aki [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Agusa, Tetsuro [Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577 (Japan); Iwata, Hisato [Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577 (Japan); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577 (Japan); Bui Cach Tuyen [Nong Lam University, Thu Duc Distr., Ho Chi Minh City (Viet Nam); Miura, Takeshi [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan)]. E-mail: miutake@agr.ehime-u.ac.jp

    2007-06-05

    To estimate the influence of water contaminants on fish reproduction in the Mekong Delta area, we sampled cultivated male catfish (Pangasianodon hypophthalmus), investigated testicular development, and measured persistent organic pollutants (POPs) and trace element levels in muscle and liver, respectively. Various testes sizes were observed although sampling took place during a short period. Histological analysis revealed that all developmental stages of germ cells were observed in catfish with large testis, whereas only necrotic spermatogonia but no other germ cells were observed in catfish with small testis. In small testis, furthermore, vacuolization and hypertrophy of Sertoli cells were observed. Measurement of POPs in muscle and trace elements in liver demonstrated that there were negative correlations between GSI and the concentrations of Pb, Mo, Rb and As. To clarify possible direct effects of Pb, Mo, Rb and As on spermatogenesis in fish, we investigated the effects of these trace elements on spermatogenesis using in vitro testicular organ culture of Japanese eel (Anguilla japonica). Treatment with each of the trace elements alone did not affect spermatogenesis. However, treatment with 10{sup -7} M of Pb, 10{sup -5} and 10{sup -4} M of Mo, 10{sup -5}-10{sup -3} M of Rb or 10{sup -5} M of As inhibited the spermatogenesis induced by 11-ketotestosterone (11KT). Furthermore, treatment with 10{sup -4} M of As in combination with 11KT caused necrosis of testicular fragments. Taken together, these results are consistent with the hypothesis that Pb, Mo, Rb and As can exert inhibitory effects on spermatogenesis in catfish inhabiting the Mekong Delta area.

  12. Autonomic computing meets SCADA security

    OpenAIRE

    Nazir, S; Patel, S; Patel, D

    2017-01-01

    © 2017 IEEE. National assets such as transportation networks, large manufacturing, business and health facilities, power generation, and distribution networks are critical infrastructures. The cyber threats to these infrastructures have increasingly become more sophisticated, extensive and numerous. Cyber security conventional measures have proved useful in the past but increasing sophistication of attacks dictates the need for newer measures. The autonomic computing paradigm mimics the auton...

  13. Autonomic neuropathy in diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Alberto eVerrotti

    2014-12-01

    Full Text Available Diabetic autonomic neuropathy (DAN is a serious and common complication of diabetes, often overlooked and misdiagnosed. It is a systemic-wide disorder that may be asymptomatic in the early stages. The most studied and clinically important form of DAN is cardiovascular autonomic neuropathy (CAN defined as the impairment of autonomic control of the cardiovascular system in patients with diabetes after exclusion of other causes. The reported prevalence of DAN varies widely depending on inconsistent definition, different diagnostic method, different patient cohorts studied. The pathogenesis is still unclear and probably multifactorial. Once DAN becomes clinically evident, no form of therapy has been identified which can effectively stop or reverse it. Prevention strategies are based on strict glycemic control with intensive insulin treatment, multifactorial intervention and lifestyle modification including control of hypertension, dyslipidemia, stop smoking, weight loss and adequate physical exercise. The present review summarizes the latest knowledge regarding clinical presentation, epidemiology, pathogenesis and management of DAN, with some mention to childhood and adolescent population.

  14. Semi autonomous mine detection system

    Energy Technology Data Exchange (ETDEWEB)

    Douglas Few; Roelof Versteeg; Herman Herman

    2010-04-01

    CMMAD is a risk reduction effort for the AMDS program. As part of CMMAD, multiple instances of semi autonomous robotic mine detection systems were created. Each instance consists of a robotic vehicle equipped with sensors required for navigation and marking, a countermine sensors and a number of integrated software packages which provide for real time processing of the countermine sensor data as well as integrated control of the robotic vehicle, the sensor actuator and the sensor. These systems were used to investigate critical interest functions (CIF) related to countermine robotic systems. To address the autonomy CIF, the INL developed RIK was extended to allow for interaction with a mine sensor processing code (MSPC). In limited field testing this system performed well in detecting, marking and avoiding both AT and AP mines. Based on the results of the CMMAD investigation we conclude that autonomous robotic mine detection is feasible. In addition, CMMAD contributed critical technical advances with regard to sensing, data processing and sensor manipulation, which will advance the performance of future fieldable systems. As a result, no substantial technical barriers exist which preclude – from an autonomous robotic perspective – the rapid development and deployment of fieldable systems.

  15. The mammalian-specific Tex19.1 gene plays an essential role in spermatogenesis and placenta-supported development.

    Science.gov (United States)

    Tarabay, Yara; Kieffer, Emmanuelle; Teletin, Marius; Celebi, Catherine; Van Montfoort, Aafke; Zamudio, Natasha; Achour, Mayada; El Ramy, Rosy; Gazdag, Emese; Tropel, Philippe; Mark, Manuel; Bourc'his, Déborah; Viville, Stéphane

    2013-08-01

    What is the consequence of Tex19.1 gene deletion in mice? The Tex19.1 gene is important in spermatogenesis and placenta-supported development. Tex19.1 is expressed in embryonic stem (ES) cells, primordial germ cells (PGCs), placenta and adult gonads. Its invalidation in mice leads to a variable impairment in spermatogenesis and reduction of perinatal survival. We generated knock-out mice and ES cells and compared them with wild-type counterparts. The phenotype of the Tex19.1 knock-out mouse line was investigated during embryogenesis, fetal development and placentation as well as during adulthood. We used a mouse model system to generate a mutant mouse line in which the Tex19.1 gene was deleted in the germline. We performed an extensive analysis of Tex19.1-deficient ES cells and assessed their in vivo differentiation potential by generating chimeric mice after injection of the ES cells into wild-type blastocysts. For mutant animals, a morphological characterization was performed for testes and ovaries and placenta. Finally, we characterized semen parameters of mutant animals and performed real-time RT-PCR for expression levels of retrotransposons in mutant testes and ES cells. While Tex19.1 is not essential in ES cells, our study points out that it is important for spermatogenesis and for placenta-supported development. Furthermore, we observed an overexpression of the class II LTR-retrotransposon MMERVK10C in Tex19.1-deficient ES cells and testes. The Tex19.1 knock-out phenotype is variable with testis morphology ranging from severely altered (in sterile males) to almost indistinguishable compared with the control counterparts (in fertile males). This variability in the testis phenotype subsequently hampered the molecular analysis of mutant testes. Furthermore, these results were obtained in the mouse, which has a second isoform (i.e. Tex19.2), while other mammals possess only one Tex19 (e.g. in humans). The fact that one gene has a role in both placentation and

  16. The distribution of cell wall polymers during antheridium development and spermatogenesis in the Charophycean green alga, Chara corallina.

    Science.gov (United States)

    Domozych, David S; Sørensen, Iben; Willats, William G T

    2009-11-01

    The production of multicellular gametangia in green plants represents an early evolutionary development that is found today in all land plants and advanced clades of the Charophycean green algae. The processing of cell walls is an integral part of this morphogenesis yet very little is known about cell wall dynamics in early-divergent green plants such as the Charophycean green algae. This study represents a comprehensive analysis of antheridium development and spermatogenesis in the green alga, Chara corallina. Microarrays of cell wall components and immunocytochemical methods were employed in order to analyse cell wall macromolecules during antheridium development. Cellulose and pectic homogalacturonan epitopes were detected throughout all cell types of the developing antheridium including the unique cell wall protuberances of the shield cells and the cell walls of sperm cell initials. Arabinogalactan protein epitopes were distributed only in the epidermal shield cell layers and anti-xyloglucan antibody binding was only observed in the capitulum region that initially yields the sperm filaments. During the terminal stage of sperm development, no cell wall polymers recognized by the probes employed were found on the scale-covered sperm cells. Antheridium development in C. corallina is a rapid event that includes the production of cell walls that contain polymers similar to those found in land plants. While pectic and cellulosic epitopes are ubiquitous in the antheridium, the distribution of arabinogalactan protein and xyloglucan epitopes is restricted to specific zones. Spermatogenesis also includes a major switch in the production of extracellular matrix macromolecules from cell walls to scales, the latter being a primitive extracellular matrix characteristic of green plants.

  17. Neonatal androgenization of hypogonadal (hpg male mice does not abolish estradiol-induced FSH production and spermatogenesis

    Directory of Open Access Journals (Sweden)

    Kerr Jeffrey B

    2005-09-01

    Full Text Available Abstract Background Testicular development is arrested in the hypogonadal (hpg mouse due to a congenital deficiency in hypothalamic gonadotropin-releasing hormone (GnRH synthesis. Chronic treatment of male hpg mice with estradiol induces FSH synthesis and secretion, and causes testicular maturation and qualitatively normal spermatogenesis. As estradiol negative feedback normally inhibits FSH production in the male, this study tested whether this paradoxical response to estradiol in the male hpg mouse might be due to inadequate masculinisation or incomplete defeminization in the neonatal period. Previous studies have demonstrated that treatment of hpg mice with testosterone propionate in the immediate neonatal period is necessary to allow full reproductive behaviors to be expressed following suitable endocrine stimulation at adult ages. Methods Hpg mice were treated with 100 μg testosterone propionate or vehicle on postnatal day 2. At 35 days of age, subgroups of these mice were treated with silastic implants containing estradiol or cholesterol. Reproductive behavior was scored in tests with steroid-primed female mice, then testicular development was assessed histologically, and measures of pituitary FSH content made at 85 days of age. Results The neonatal testosterone propionate treatment successfully defeminized female litter mates, as revealed by impaired vaginal opening and deficiencies in lordosis behavior, and it allowed appropriate male reproductive behavior to be expressed in a proportion of the hpg males when tested at an adult age. However, neonatal androgen supplementation did not block or even reduce the subsequent actions of estradiol in increasing pituitary FSH content, nor did it affect the ability of estradiol to induce qualitatively normal spermatogenesis. Conclusion The ability of the hpg male to show a "female" neuroendocrine response to estradiol is not a result of inadequate androgenization during neonatal development, and

  18. Protective Effect of Melatonin on the Quality of Spermatogenesis and Sperm Parameters in the Mice Treated with Acetylsalicylic Acid

    Directory of Open Access Journals (Sweden)

    F. Mohammad Ghasemi

    2012-01-01

    Full Text Available Introduction & Objective: Melatonin, the most important secretary hormone of pineal gland, as a powerful antioxidant has a high potent for neutralizing the toxicity of drugs. In the present study we aimed to demonstrate the effect of melatonin on testicular damage and sperm parameters deficiency induced by acetylsalicylic acid, in adult male mice. Materials & Methods: Male NMRI mice were divided into 4 groups: 1 control 2 acetylsalicylic acid treated group 3 melatonin treated group 4 Melatonin-acetylsalicylic acid treated group. Acetylsalicylic acid was administered at a dose of 50mg/kg orally through gavage for 14 days. Melatonin was administered in dose of 10 mg/kg for 5 days intraperitoneally. The control mice were received vehicle (normal saline orally through gavage. The animals were sacrificed and their testes and epididymis were dissected on the 15th day after the treatment. Evaluations were made by determining Johnson's score, epididymal sperm count, and sperm morphology and sperm motility. Statistical analysis was performed by ANOVA test. Results: Acetylsalicylic acid treated mice showed a reduction in Johnson's score and quality of spermatogenesis (P<0.05, sperm count, normal morphology and motility percent (P<0.001, compared to the control. Melatonin in group 4, significantly increased maturation of seminiferous tubules (P<0.05, and quality and quantity of sperm parameters (P<0.05 in comparison with group 2. Conclusion: It seems that intraperitoneal administration of melatonin for 5 days is a potentially beneficial agent to improve the quality of spermatogenesis and sperm parameters in testis damaged by acetylsalicylic acid, probably by decreasing oxidative stresses. (Sci J Hamadan Univ Med Sci 2012;18(4:29-36

  19. Sustainable Disruptions

    DEFF Research Database (Denmark)

    Friis, Silje Alberthe Kamille; Kjær, Lykke Bloch

    2016-01-01

    Since 2012 the Sustainable Disruptions (SD) project at the Laboratory for Sustainability at Design School Kolding (DK) has developed and tested a set of design thinking tools, specifically targeting the barriers to economically, socially, and environmentally sustainable business development...... invested in the issue of sustainable business development, in particular the leaders and employees of SMEs, but also to design education seeking new ways to consciously handle and teach the complexity inherent in sustainable transformation. Findings indicate that the SD design thinking approach contributes....... The tools have been applied in practice in collaboration with 11 small and medium sized companies (SMEs). The study investigates these approaches to further understand how design thinking can contribute to sustainable transition in a business context. The study and the findings are relevant to organizations...

  20. Computational sustainability

    CERN Document Server

    Kersting, Kristian; Morik, Katharina

    2016-01-01

    The book at hand gives an overview of the state of the art research in Computational Sustainability as well as case studies of different application scenarios. This covers topics such as renewable energy supply, energy storage and e-mobility, efficiency in data centers and networks, sustainable food and water supply, sustainable health, industrial production and quality, etc. The book describes computational methods and possible application scenarios.

  1. Sustainable transformation

    DEFF Research Database (Denmark)

    Andersen, Nicolai Bo

    This paper is about sustainable transformation with a particular focus on listed buildings. It is based on the notion that sustainability is not just a question of energy conditions, but also about the building being robust. Robust architecture means that the building can be maintained and rebuilt...... theoretical lenses. It is proposed that three parameters concerning the ꞌtransformabilityꞌ of the building can contribute to a more nuanced understanding of sustainable transformation: technical aspects, programmatic requirements and narrative value. It is proposed that the concept of ꞌsustainable...

  2. Autonomous Cryogenic Load Operations: KSC Autonomous Test Engineer

    Science.gov (United States)

    Shrading, Nicholas J.

    2012-01-01

    The KSC Autonomous Test Engineer (KATE) program has a long history at KSC. Now a part of the Autonomous Cryogenic Load Operations (ACLO) mission, this software system has been sporadically developed over the past 20+ years. Originally designed to provide health and status monitoring for a simple water-based fluid system, it was proven to be a capable autonomous test engineer for determining sources of failure in. the system, As part.of a new goal to provide this same anomaly-detection capability for a complicated cryogenic fluid system, software engineers, physicists, interns and KATE experts are working to upgrade the software capabilities and graphical user interface. Much progress was made during this effort to improve KATE. A display ofthe entire cryogenic system's graph, with nodes for components and edges for their connections, was added to the KATE software. A searching functionality was added to the new graph display, so that users could easily center their screen on specific components. The GUI was also modified so that it displayed information relevant to the new project goals. In addition, work began on adding new pneumatic and electronic subsystems into the KATE knowledgebase, so that it could provide health and status monitoring for those systems. Finally, many fixes for bugs, memory leaks, and memory errors were implemented and the system was moved into a state in which it could be presented to stakeholders. Overall, the KATE system was improved and necessary additional features were added so that a presentation of the program and its functionality in the next few months would be a success.

  3. Autonomous Cryogenic Load Operations: Knowledge-Based Autonomous Test Engineer

    Science.gov (United States)

    Schrading, J. Nicolas

    2013-01-01

    The Knowledge-Based Autonomous Test Engineer (KATE) program has a long history at KSC. Now a part of the Autonomous Cryogenic Load Operations (ACLO) mission, this software system has been sporadically developed over the past 20 years. Originally designed to provide health and status monitoring for a simple water-based fluid system, it was proven to be a capable autonomous test engineer for determining sources of failure in the system. As part of a new goal to provide this same anomaly-detection capability for a complicated cryogenic fluid system, software engineers, physicists, interns and KATE experts are working to upgrade the software capabilities and graphical user interface. Much progress was made during this effort to improve KATE. A display of the entire cryogenic system's graph, with nodes for components and edges for their connections, was added to the KATE software. A searching functionality was added to the new graph display, so that users could easily center their screen on specific components. The GUI was also modified so that it displayed information relevant to the new project goals. In addition, work began on adding new pneumatic and electronic subsystems into the KATE knowledge base, so that it could provide health and status monitoring for those systems. Finally, many fixes for bugs, memory leaks, and memory errors were implemented and the system was moved into a state in which it could be presented to stakeholders. Overall, the KATE system was improved and necessary additional features were added so that a presentation of the program and its functionality in the next few months would be a success.

  4. The course of autonomic neural function in chronic uraemic patients during haemodialysis treatment.

    Science.gov (United States)

    Vita, G; Savica, V; Puglisi, R M; Marabello, L; Bellinghieri, G; Messina, C

    1992-01-01

    Autonomic function was followed in 19 patients with uraemia on chronic haemodialysis treatment over a period of 18 months. A smaller group of 12 patients were studied over 56 months. The battery of cardiovascular reflex tests included R-R interval variation test, deep breathing, Valsalva manoeuvre, heart rate, and blood pressure responses to standing and sustained handgrip. Two indices of autonomic function were measured: the autonomic score, and the confidence level on Bayesian analysis. There was great variability in the course of autonomic function over the period studied, with improvement occurring in some subjects and deterioration in others. In addition some patients did not develop any abnormality. Among those patients with uraemia and normal autonomic function at the start of the study, a deterioration occurred in 33-36% in the 18-month follow-up but in 62.5% in the 56-month follow-up. As a group there was no significant change in autonomic function during follow-up, although a clear trend to deterioration was found despite chronic haemodialysis treatment.

  5. Activated Cdc42 kinase regulates Dock localization in male germ cells during Drosophila spermatogenesis.

    Science.gov (United States)

    Abdallah, Abbas M; Zhou, Xin; Kim, Christine; Shah, Kushani K; Hogden, Christopher; Schoenherr, Jessica A; Clemens, James C; Chang, Henry C

    2013-06-15

    Deregulation of the non-receptor tyrosine kinase ACK1 (Activated Cdc42-associated kinase) correlates with poor prognosis in cancers and has been implicated in promoting metastasis. To further understand its in vivo function, we have characterized the developmental defects of a null mutation in Drosophila Ack, which bears a high degree of sequence similarity to mammalian ACK1 but lacks a CRIB domain. We show that Ack, while not essential for viability, is critical for sperm formation. This function depends on Ack tyrosine kinase activity and is required cell autonomously in differentiating male germ cells at or after the spermatocyte stage. Ack associates predominantly with endocytic clathrin sites in spermatocytes, but disruption of Ack function has no apparent effect on clathrin localization and receptor-mediated internalization of Boss (Bride of sevenless) protein in eye discs. Instead, Ack is required for the subcellular distribution of Dock (dreadlocks), the Drosophila homolog of the SH2- and SH3-containing adaptor protein Nck. Moreover, Dock forms a complex with Ack, and the localization of Dock in male germ cells depends on its SH2 domain. Together, our results suggest that Ack-dependent tyrosine phosphorylation recruits Dock to promote sperm differentiation. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Towards the Development of Autonomous Ferries

    OpenAIRE

    Bitar, Glenn Ivan

    2017-01-01

    Autonomous ships is at the moment a heavily researched topic in the maritime industry. Development to introduce autonomous ferries in the Norwegian fjords is under way. This thesis is a study of technical and formal challenges related to autonomous ferries. The thesis goes into topics such as industrial control systems for ships, path planning and collision avoidance algorithms, as well as automatic docking. Additionally, information and statistics regarding ferry activities in Norway are pre...

  7. The Human Element and Autonomous Ships

    OpenAIRE

    Sauli Ahvenjärvi

    2016-01-01

    The autonomous ship technology has become a “hot” topic in the discussion about more efficient, environmentally friendly and safer sea transportation solutions. The time is becoming mature for the introduction of commercially sensible solutions for unmanned and fully autonomous cargo and passenger ships. Safety will be the most interesting and important aspect in this development. The utilization of the autonomous ship technology will have many effects on the safety, both positive and negativ...

  8. Autonomous Exploration Using an Information Gain Metric

    Science.gov (United States)

    2016-03-01

    navigation goals, serving to drive an autonomous system. By continually moving to these navigation goals and taking measurements, the system works to...ARL-TR-7638 ● MAR 2016 US Army Research Laboratory Autonomous Exploration Using an Information Gain Metric by Nicholas C Fung...Laboratory Autonomous Exploration Using an Information Gain Metric by Nicholas C Fung, Jason M Gregory, and John G Rogers Computational and

  9. DARTS: Deceiving Autonomous Cars with Toxic Signs

    OpenAIRE

    Sitawarin, Chawin; Bhagoji, Arjun Nitin; Mosenia, Arsalan; Chiang, Mung; Mittal, Prateek

    2018-01-01

    Sign recognition is an integral part of autonomous cars. Any misclassification of traffic signs can potentially lead to a multitude of disastrous consequences, ranging from a life-threatening accident to a large-scale interruption of transportation services relying on autonomous cars. In this paper, we propose and examine realistic security attacks against sign recognition systems for Deceiving Autonomous caRs with Toxic Signs (we call the proposed attacks DARTS). Leveraging the concept of ad...

  10. Design of an Autonomous Forklift Using Kinect

    OpenAIRE

    Abdellatif Mohamed; Shoeir Metwali; Talaat Omar; Gabalah Mahmoud; Elbably Mohamed; Saleh Saleh

    2018-01-01

    Material handling is a necessary, but expensive activity in factories. Autonomous robot technology can help reduce the cost and relax humans from the exhaustive job of driving forklifts. In this paper, we describe the mechatronics design and implementation of an autonomous forklift. The robot can perceive the 3D dynamic world and can plan its motion autonomously to lift materials from a source to target locations. Dynamic map of the world is built using data from a Microsoft Kinect head and r...

  11. Implementing a Cloud Platform for Autonomous Driving

    OpenAIRE

    Liu, Shaoshan; Tang, Jie; Wang, Chao; Wang, Quan; Gaudiot, Jean-Luc

    2017-01-01

    Autonomous driving clouds provide essential services to support autonomous vehicles. Today these services include but not limited to distributed simulation tests for new algorithm deployment, offline deep learning model training, and High-Definition (HD) map generation. These services require infrastructure support including distributed computing, distributed storage, as well as heterogeneous computing. In this paper, we present the details of how we implement a unified autonomous driving clo...

  12. Science Data Understanding for Autonomous Rover Exploration

    Data.gov (United States)

    National Aeronautics and Space Administration — Autonomous rover traversal speed and capabilities are rapidly increasing, but communications bandwidth for planetary exploration remains limited. In order to...

  13. A Generic Architecture for Autonomous Uninhabited Vehicles

    National Research Council Canada - National Science Library

    Barbier, Magali; Gabard, Jean-Francois; Ayreault, Herve

    2007-01-01

    ...; few solutions propose architecture adaptive to several types of platform. Autonomous vehicles that move in partially known and dynamic environments have to deal with asynchronous disruptive events...

  14. Public Health, Ethics, and Autonomous Vehicles.

    Science.gov (United States)

    Fleetwood, Janet

    2017-04-01

    With the potential to save nearly 30 000 lives per year in the United States, autonomous vehicles portend the most significant advance in auto safety history by shifting the focus from minimization of postcrash injury to collision prevention. I have delineated the important public health implications of autonomous vehicles and provided a brief analysis of a critically important ethical issue inherent in autonomous vehicle design. The broad expertise, ethical principles, and values of public health should be brought to bear on a wide range of issues pertaining to autonomous vehicles.

  15. Sustainable Universities

    DEFF Research Database (Denmark)

    Grindsted, Thomas Skou

    2011-01-01

    , has put a counter pressure on the university, forcing it to review its role as a driver for sustainable development. Today, universities and intergovernmental institutions have developed more than 31 SHE declarations, and more than 1400 universities have signed a SHE declaration globally. However....... Declarations tend to have impact on three trends. Firstly, there is emerging international consensus on the university’s role and function in relation to sustainable development; secondly, the emergence of national legislation, and thirdly, an emerging international competition to be leader in sustainable......Declarations on Sustainability in Higher Education (SHE) can be viewed as a piece of international regulation. Over the past 30 years research at universities has produced convincing data to warn about deterioration of the environment, resource scarcity and the need for sustainability. This in turn...

  16. Sustainable Transition

    DEFF Research Database (Denmark)

    Hansen, Ole Erik; Søndergård, Bent

    2014-01-01

    What. The chapter addresses designing for sustainability as interventions in socio-technical systems and social practices of users and communities. It calls for reflexive design practices challenging dominant regimes and shaping alternative design spaces. The specific case is the reconfiguration...... of agendas/vision, technologies, actors and institutions in the emergent design of an urban mobility system based on an electric car sharing system. Why. Designing for sustainability is a fundamental challenge for future design practices; designers have to obtain an ability to contribute to sustainable...... transition processes. Where. Addresses design processes aimed at sustainable transition enacted in complex social settings, socio-technical systems involving many different actors and agendas. How. The chapter outlines a conceptual and analytic framework for a reflexive design practice for sustainability...

  17. Autonomous systems for plant protection

    DEFF Research Database (Denmark)

    Griepentrog, Hans W.; Ruckelhausen, Arno; Jørgensen, Rasmus N.

    2010-01-01

    of autonomous operations related to crop protection probably commercially available in the near future. Scouting and monitoring together with the efficient application of chemicals or mechanical treatments are operations which can be successful automated. Drawbacks are that current systems are lacking robust......Advances in automation are demanded by the market mainly as a response to high labor costs. Robotic outdoor systems are ready to allow not only economically viable operations but also increased efficiency in agriculture, horticulture and forestry. The aim of this chapter is to give examples...

  18. Autonomous quality assurance and troubleshooting

    Science.gov (United States)

    DuPlain, Ronald F.; Radziwill, Nicole M.; Shelton, Amy L.

    2006-06-01

    To improve operational availability (the proportion of time that a telescope is able to accomplish what a visiting observer wants at the time the observation is scheduled), response time to faults must be minimized. One way this can be accomplished is by characterizing the relationships and interdependencies between components in a control system, developing algorithms to identify the root cause of a problem, and capturing expert knowledge of a system to simplify the process of troubleshooting. Results from a prototype development are explained, along with deployment issues. Implications for the future, such as effective knowledge representation and management, and learning processes which integrate autonomous and interactive components, are discussed.

  19. Topological entropy of autonomous flows

    Energy Technology Data Exchange (ETDEWEB)

    Badii, R. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    When studying fluid dynamics, especially in a turbulent regime, it is crucial to estimate the number of active degrees of freedom or of localized structures in the system. The topological entropy quantifies the exponential growth of the number of `distinct` orbits in a dynamical system as a function of their length, in the infinite spatial resolution limit. Here, I illustrate a novel method for its evaluation, which extends beyond maps and is applicable to any system, including autonomous flows: these are characterized by lack of a definite absolute time scale for the orbit lengths. (author) 8 refs.

  20. Autonomous sensor manager agents (ASMA)

    Science.gov (United States)

    Osadciw, Lisa A.

    2004-04-01

    Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

  1. Autonomously managed electrical power systems

    Science.gov (United States)

    Callis, Charles P.

    1986-01-01

    The electric power systems for future spacecraft such as the Space Station will necessarily be more sophisticated and will exhibit more nearly autonomous operation than earlier spacecraft. These new power systems will be more reliable and flexible than their predecessors offering greater utility to the users. Automation approaches implemented on various power system breadboards are investigated. These breadboards include the Hubble Space Telescope power system test bed, the Common Module Power Management and Distribution system breadboard, the Autonomusly Managed Power System (AMPS) breadboard, and the 20 kilohertz power system breadboard. Particular attention is given to the AMPS breadboard. Future plans for these breadboards including the employment of artificial intelligence techniques are addressed.

  2. The Autonomous Pathogen Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Dzenitis, J M; Makarewicz, A J

    2009-01-13

    We developed, tested, and now operate a civilian biological defense capability that continuously monitors the air for biological threat agents. The Autonomous Pathogen Detection System (APDS) collects, prepares, reads, analyzes, and reports results of multiplexed immunoassays and multiplexed PCR assays using Luminex{copyright} xMAP technology and flow cytometer. The mission we conduct is particularly demanding: continuous monitoring, multiple threat agents, high sensitivity, challenging environments, and ultimately extremely low false positive rates. Here, we introduce the mission requirements and metrics, show the system engineering and analysis framework, and describe the progress to date including early development and current status.

  3. BART: The Czech Autonomous Observatory

    Czech Academy of Sciences Publication Activity Database

    Nekola, Martin; Hudec, René; Jelínek, M.; Kubánek, P.; Štrobl, Jan; Polášek, Cyril

    2010-01-01

    Roč. 2010, Spec. Is. (2010), 103986/1-103986/5 ISSN 1687-7969. [Workshop on Robotic Autonomous Observatories. Málaga, 18.05.2009-21.05.2009] R&D Projects: GA ČR GA205/08/1207 Grant - others:ESA(XE) ESA-PECS project No. 98023; Spanish Ministry of Education and Science(ES) AP2003-1407 Institutional research plan: CEZ:AV0Z10030501 Keywords : robotic telescope * BART * gamma ray bursts Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics http://www.hindawi.com/journals/aa/2010/103986.html

  4. Teaching chemistry with sustainability

    Directory of Open Access Journals (Sweden)

    Antonia G. Rojas-Fernández

    2017-04-01

    Full Text Available Increased awareness on a critical association between the natural environment and human development gave rise multiple projects, aiming to protect the natural environment and to preserve it for future generations. Chemists must be acquainted with the principles of green chemistry and the need to practice experimental chemistry with cleaner chemical reactions and sustainability. This is a major concern for all the educators forming new professionals within the Chemistry, Pharmacology and Biology curricula in the Faculty for Higher Studies Zaragoza from the National Autonomous University of Mexico. With this in mind, we start our teachings explaining from the very beginning, how important it is to perform microscale techniques and to follow the principles of green chemistry in the Basic Science Laboratory. Furthermore, we have modified, designed and evaluated working procedures related with chemical synthesis, kinetics and calorimetry. By doing this, we managed to greatly reduce the amount of reagents required and residues generated. Some laboratory reagents have been substituted with renewable substances. We have also included in our programme a regular treatment of residues generated during everyday laboratory work. Our goal is to emphasize the importance of minimizing the environmental impact of chemistry and to prepare environmentally concerned professionals who keep sustainability as main priority and perform chemistry procedures with good laboratory practice routines.

  5. Autonomic neuropathy in Fabry disease: a prospective study using the Autonomic Symptom Profile and cardiovascular autonomic function tests

    NARCIS (Netherlands)

    Biegstraaten, Marieke; van Schaik, Ivo N.; Wieling, Wouter; Wijburg, Frits A.; Hollak, Carla E. M.

    2010-01-01

    ABSTRACT: BACKGROUND: Fabry patients have symptoms and signs compatible with autonomic dysfunction. These symptoms and signs are considered to be due to impairment of the peripheral nervous system, but findings indicative of autonomic neuropathy in other diseases, such as orthostatic intolerance and

  6. Structured control for autonomous robots

    International Nuclear Information System (INIS)

    Simmons, R.G.

    1994-01-01

    To operate in rich, dynamic environments, autonomous robots must be able to effectively utilize and coordinate their limited physical and occupational resources. As complexity increases, it becomes necessary to impose explicit constraints on the control of planning, perception, and action to ensure that unwanted interactions between behaviors do not occur. This paper advocates developing complex robot systems by layering reactive behaviors onto deliberative components. In this structured control approach, the deliberative components handle normal situations and the reactive behaviors, which are explicitly constrained as to when and how they are activated, handle exceptional situations. The Task Control Architecture (TCA) has been developed to support this approach. TCA provides an integrated set of control constructs useful for implementing deliberative and reactive behaviors. The control constructs facilitate modular and evolutionary system development: they are used to integrate and coordinate planning, perception, and execution, and to incrementally improve the efficiency and robustness of the robot systems. To date, TCA has been used in implementing a half-dozen mobile robot systems, including an autonomous six-legged rover and indoor mobile manipulator

  7. Autonomous Robotic Inspection in Tunnels

    Science.gov (United States)

    Protopapadakis, E.; Stentoumis, C.; Doulamis, N.; Doulamis, A.; Loupos, K.; Makantasis, K.; Kopsiaftis, G.; Amditis, A.

    2016-06-01

    In this paper, an automatic robotic inspector for tunnel assessment is presented. The proposed platform is able to autonomously navigate within the civil infrastructures, grab stereo images and process/analyse them, in order to identify defect types. At first, there is the crack detection via deep learning approaches. Then, a detailed 3D model of the cracked area is created, utilizing photogrammetric methods. Finally, a laser profiling of the tunnel's lining, for a narrow region close to detected crack is performed; allowing for the deduction of potential deformations. The robotic platform consists of an autonomous mobile vehicle; a crane arm, guided by the computer vision-based crack detector, carrying ultrasound sensors, the stereo cameras and the laser scanner. Visual inspection is based on convolutional neural networks, which support the creation of high-level discriminative features for complex non-linear pattern classification. Then, real-time 3D information is accurately calculated and the crack position and orientation is passed to the robotic platform. The entire system has been evaluated in railway and road tunnels, i.e. in Egnatia Highway and London underground infrastructure.

  8. Autonomous Lawnmower using FPGA implementation.

    Science.gov (United States)

    Ahmad, Nabihah; Lokman, Nabill bin; Helmy Abd Wahab, Mohd

    2016-11-01

    Nowadays, there are various types of robot have been invented for multiple purposes. The robots have the special characteristic that surpass the human ability and could operate in extreme environment which human cannot endure. In this paper, an autonomous robot is built to imitate the characteristic of a human cutting grass. A Field Programmable Gate Array (FPGA) is used to control the movements where all data and information would be processed. Very High Speed Integrated Circuit (VHSIC) Hardware Description Language (VHDL) is used to describe the hardware using Quartus II software. This robot has the ability of avoiding obstacle using ultrasonic sensor. This robot used two DC motors for its movement. It could include moving forward, backward, and turning left and right. The movement or the path of the automatic lawn mower is based on a path planning technique. Four Global Positioning System (GPS) plot are set to create a boundary. This to ensure that the lawn mower operates within the area given by user. Every action of the lawn mower is controlled by the FPGA DE' Board Cyclone II with the help of the sensor. Furthermore, Sketch Up software was used to design the structure of the lawn mower. The autonomous lawn mower was able to operate efficiently and smoothly return to coordinated paths after passing the obstacle. It uses 25% of total pins available on the board and 31% of total Digital Signal Processing (DSP) blocks.

  9. Dynamics of histone H2A, H4 and HS1ph during spermatogenesis with a focus on chromatin condensation and maturity of spermatozoa.

    Science.gov (United States)

    Zhang, Zhao-Hui; Mu, Shu-Mei; Guo, Ming-Shen; Wu, Jiang-Li; Li, Yan-Qin; Zhang, Han; Wang, Ying; Kang, Xian-Jiang

    2016-04-28

    Histones and histone phosphorylation play vital roles during animal spermatogenesis and spermatozoa maturation. The dynamic distribution of histones H2A and H4 and phosphorylated H2A and H4 at serine 1 (HS1ph) was explored in mammalian and Decapoda germ cells, with a special focus on the distribution of H2A, H4 and HS1ph between mouse condensed spermatozoa chromatin and crab non-condensed spermatozoa chromatin. The distribution of histone marks was also analysed in mature spermatozoa with different chromatin structures. Histone H2A and H4 marks were closely associated with the relatively loose chromatin structure in crab spermatozoa. The significant decrease in the HS1ph signal during spermatogenesis suggests that eliminating most of these epigenetic marks in the nucleusis closely associated with spermatozoa maturity.

  10. Autoradiographic studies on [sup 3]H-fucose incorporation into manubria and its translocation to antheridial space during spermatogenesis in Chara vulgaris L

    Energy Technology Data Exchange (ETDEWEB)

    Gosek, A.; Kwiatkowska, M. (Lodz Univ. (Poland))

    1993-01-01

    The internal space of antheridium in Chara vulgaris L. is filled with the PAS-positive polysaccharide mucilage. It is produced and secreted by non-generative, polyploidal cells - manubria. Autoradiographic studies with the use of [sup 3]H-fucose have shown that this precursor is incorporated into polysaccharidial compounds at the manubrium surface. The dynamics of this process is different in proliferative phase than after symplasmic isolation of antheridium. The translocation of mucilage into antheridial space is very intensive, especially at the older developmental stages of antheridium. The data obtained after 12-hour post incubation indicated secondary metabolic changes of mucilage. The decrease in total radioactivity per investigated section is most intensive by the end of spermatogenesis. These facts seem to confirm the assumption about nutritive role of mucilage filling Chara antheridium during the process of spermatogenesis. (author). 19 refs, 3 figs, 2 tabs.

  11. High-Throughput Screening for Spermatogenesis Candidate Genes in the AZFc Region of the Y Chromosome by Multiplex Real Time PCR Followed by High Resolution Melting Analysis

    OpenAIRE

    Alechine, Evguenia; Corach, Daniel

    2014-01-01

    Microdeletions in the AZF region of the Y chromosome are among the most frequent genetic causes of male infertility, although the specific role of the genes located in this region is not fully understood. AZFa and AZFb deletions impair spermatogenesis since no spermatozoa are found in the testis. Deletions of the AZFc region, despite being the most frequent in azoospermic patients, do not correlate with spermatogenic failure. Therefore, the aim of this work was to develop a screening method t...

  12. High-throughput screening for spermatogenesis candidate genes in the AZFc region of the Y chromosome by multiplex real time PCR followed by high resolution melting analysis

    OpenAIRE

    Alechine, Evguenia; Corach, Daniel

    2017-01-01

    Microdeletions in the AZF region of the Y chromosome are among the most frequent genetic causes of male infertility, although the specific role of the genes located in this region is not fully understood. AZFa and AZFb deletions impair spermatogenesis since no spermatozoa are found in the testis. Deletions of the AZFc region, despite being the most frequent in azoospermic patients, do not correlate with spermatogenic failure. Therefore, the aim of this work was to develop a screening method t...

  13. Description of spermatogenesis and sperm ultrastructure of Acanthostomum (Atrophocaecum) aswaninesis Wannas, 1977 (Digenea, Acanthostomatidae), a parasite of Bagrus bayad in Egypt

    OpenAIRE

    Taeleb, A.A.; Mohammadein, A.M.

    2013-01-01

    Spermatogenesis and the spermatozoon of Acanthostomum (Atrophocaecum) aswaninesis, were studied by transmission electron microscopy. Spermatogonia characterized by a large nucleo-cytoplasmic ratio, give rise to two generations of spermatocytes. The secondary spermatocytes divide forming early spermatids that fuse together into a common cytoplasmic mass. Spermiogenesis begins with the formation of the zone of differentiation in front of 2 centrioles associated by an inter-centriolar body. E...

  14. An autonomous weeding robot for organic farming

    NARCIS (Netherlands)

    Bakker, T.; Asselt, van C.J.; Bontsema, J.; Müller, J.; Straten, van G.

    2006-01-01

    The objective of this research is the replacement of hand weeding in organic farming by a device working autonomously at ¯eld level. The autonomous weeding robot was designed using a structured design approach, giving a good overview of the total design. A vehicle was developed with a diesel engine,

  15. Autonomous Control of Space Reactor Systems

    International Nuclear Information System (INIS)

    Belle R. Upadhyaya; K. Zhao; S.R.P. Perillo; Xiaojia Xu; M.G. Na

    2007-01-01

    Autonomous and semi-autonomous control is a key element of space reactor design in order to meet the mission requirements of safety, reliability, survivability, and life expectancy. Interrestrial nuclear power plants, human operators are available to perform intelligent control functions that are necessary for both normal and abnormal operational conditions

  16. The Cardiovascular Autonomic Nervous System and Anaesthesia

    African Journals Online (AJOL)

    QuickSilver

    part of our training and practice is spent acquiring skills in averting or utilizing the autonomic nervous system effects of anaesthetic drugs or surgical procedures under a variety of pathophysiological conditions. Moreover, many of these pathophysiological condi- tions may be associated with impaired preoperative autonomic ...

  17. Blunted autonomic response in cluster headache patients

    DEFF Research Database (Denmark)

    Barloese, Mads; Brinth, Louise; Mehlsen, Jesper

    2015-01-01

    BACKGROUND: Cluster headache (CH) is a disabling headache disorder with chronobiological features. The posterior hypothalamus is involved in CH pathophysiology and is a hub for autonomic control. We studied autonomic response to the head-up tilt table test (HUT) including heart rate variability...

  18. Basic and clinical pharmacology of autonomic drugs.

    Science.gov (United States)

    Becker, Daniel E

    2012-01-01

    Autonomic drugs are used clinically to either imitate or inhibit the normal functions of the sympathetic and parasympathetic nervous systems. A large number of additional drug classes also interact with these systems to produce a stunning number of possible side effects. This article reviews the basic function of the autonomic nervous system and the various drug classes that act within these neural synapses.

  19. Safe and Autonomous Drones for Urban Flight

    Science.gov (United States)

    Krishnakumar, Kalmanje

    2016-01-01

    Autonomous vehicles are no longer futuristic technology; in fact, there are already cars with self-driving features on the road. Over the next five years, the connected vehicles will disrupt the entire automotive and UAS ecosystems. The industry will undergo fundamental change as semi-autonomous driving and flying emerges, followed by an eventual shift to full autonomy.

  20. Autonomous Control of Space Reactor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Belle R. Upadhyaya; K. Zhao; S.R.P. Perillo; Xiaojia Xu; M.G. Na

    2007-11-30

    Autonomous and semi-autonomous control is a key element of space reactor design in order to meet the mission requirements of safety, reliability, survivability, and life expectancy. Interrestrial nuclear power plants, human operators are avilable to perform intelligent control functions that are necessary for both normal and abnormal operational conditions.

  1. Planning Flight Paths of Autonomous Aerobots

    Science.gov (United States)

    Kulczycki, Eric; Elfes, Alberto; Sharma, Shivanjli

    2009-01-01

    Algorithms for planning flight paths of autonomous aerobots (robotic blimps) to be deployed in scientific exploration of remote planets are undergoing development. These algorithms are also adaptable to terrestrial applications involving robotic submarines as well as aerobots and other autonomous aircraft used to acquire scientific data or to perform surveying or monitoring functions.

  2. Autonomic dysfunction in cirrhosis and portal hypertension

    DEFF Research Database (Denmark)

    Dümcke, Christine Winkler; Møller, Søren

    2008-01-01

    Liver cirrhosis and portal hypertension are frequently associated with signs of circulatory dysfunction and peripheral polyneuropathy, which includes defects of the autonomic nervous system. Autonomic dysfunction, which is seen in both alcoholic and non-alcoholic liver cirrhosis and increases wit...

  3. Intelligent autonomous systems 12. Vol. 2. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sukhan [Sungkyunkwan Univ., Gyeonggi-Do (Korea, Republic of). College of Information and Communication Engineering; Yoon, Kwang-Joon [Konkuk Univ., Seoul (Korea, Republic of); Cho, Hyungsuck [Daegu Gyeongbuk Institute of Science and Technology, Daegu (Korea, Republic of); Lee, Jangmyung (eds.) [Pusan National Univ. (Korea, Republic of). Dept. of Electronics Engineering

    2013-02-01

    Recent research in Intelligent and Autonomous Systems. Volume 2 of the proceedings of the 12th International Conference IAS-12, held June 26-29, 2012, jeju Island, Korea. Written by leading experts in the field. Intelligent autonomous systems are emerged as a key enabler for the creation of a new paradigm of services to humankind, as seen by the recent advancement of autonomous cars licensed for driving in our streets, of unmanned aerial and underwater vehicles carrying out hazardous tasks on-site, and of space robots engaged in scientific as well as operational missions, to list only a few. This book aims at serving the researchers and practitioners in related fields with a timely dissemination of the recent progress on intelligent autonomous systems, based on a collection of papers presented at the 12th International Conference on Intelligent Autonomous Systems, held in Jeju, Korea, June 26-29, 2012. With the theme of ''Intelligence and Autonomy for the Service to Humankind, the conference has covered such diverse areas as autonomous ground, aerial, and underwater vehicles, intelligent transportation systems, personal/domestic service robots, professional service robots for surgery/rehabilitation, rescue/security and space applications, and intelligent autonomous systems for manufacturing and healthcare. This volume 2 includes contributions devoted to Service Robotics and Human-Robot Interaction and Autonomous Multi-Agent Systems and Life Engineering.

  4. Sustainable responsibilities?

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    2015-01-01

    This working paper analyzes the conceptions of corporate responsibility for sustainable development in EU policies on CSR. The notion of corporate responsibility has until recently been limited to economical and legal responsibilities. Based on this narrow conception of corporate responsibility.......e. a combination of destruction and construction, this chapter will deconstruct conceptions of responsibility for sustainable development in these EU documents on CSR. A deconstructive conceptual analysis involves destructing dominant interpretations of a text and allowing for constructions of alternative...... such as sustainability actually means, but on what the concept says and does not say. A deconstructive analysis of EU policies on CSR, then, pinpoints that such policies are sites of conceptual struggles. This kind of analysis is suitable for studying conceptions of corporate responsibility for sustainable development...

  5. Sustainable Cities

    DEFF Research Database (Denmark)

    Georg, Susse; Garza de Linde, Gabriela Lucía

    Judging from the number of communities and cities striving or claiming to be sustainable and how often eco-development is invoked as the means for urban regeneration, it appears that sustainable and eco-development have become “the leading paradigm within urban development” (Whitehead 2003......), urban design competitions are understudied mechanisms for bringing about field level changes. Drawing on actor network theory, this paper examines how urban design competitions may bring about changes within the professional field through the use of intermediaries such as a sustainable planning....../assessment tool. The context for our study is urban regeneration in one Danish city, which had been suffering from industrial decline and which is currently investing in establishing a “sustainable city”. Based on this case study we explore how the insights and inspiration evoked in working with the tool...

  6. Sustainable transformation

    DEFF Research Database (Denmark)

    Andersen, Nicolai Bo

    This paper is about sustainable transformation with a particular focus on listed buildings. It is based on the notion that sustainability is not just a question of energy conditions, but also about the building being robust. Robust architecture means that the building can be maintained and rebuilt......, that it can be adapted to changing functional needs, and that it has an architectural and cultural value. A specific proposal for a transformation that enhances the architectural qualities and building heritage values of an existing building forms the empirical material, which is discussed using different...... theoretical lenses. It is proposed that three parameters concerning the ꞌtransformabilityꞌ of the building can contribute to a more nuanced understanding of sustainable transformation: technical aspects, programmatic requirements and narrative value. It is proposed that the concept of ꞌsustainable...

  7. Sustainability reporting

    NARCIS (Netherlands)

    Kolk, A.

    2005-01-01

    This article gives an overview of developments in sustainability (also sometimes labelled corporate social responsibility) reporting. The article will first briefly indicate how accountability on social and environmental issues started, already in the 1970s when social reports were published.

  8. Agriculture: Sustainability

    Science.gov (United States)

    Sustainability creates and maintains the conditions under which humans and nature can exist in productive harmony, that permit fulfilling the food, feed, and fiber needs of our country and the social, economic and other requirements.

  9. Sustainable consumption

    DEFF Research Database (Denmark)

    Prothero, Andrea; Dobscha, Susan; Freund, Jim

    2011-01-01

    This essay explores sustainable consumption and considers possible roles for marketing and consumer researchers and public policy makers in addressing the many sustainability challenges that pervade our planet. Future research approaches to this interdisciplinary topic need to be comprehensive...... and systematic and will benefit from a variety of different perspectives. There are a number of opportunities for future research, and three areas are explored in detail. First, the essay considers the inconsistency between the attitudes and behaviors of consumers with respect to sustainability; next, the agenda...... is broadened to explore the role of individual citizens in society; and finally, a macro institutional approach to fostering sustainability is explored. Each of these areas is examined in detail and possible research avenues and public policy initiatives are considered within each of these separate...

  10. Sustainable Consumption

    DEFF Research Database (Denmark)

    Røpke, Inge

    2015-01-01

    The intention of this chapter is to explore the role of consumption and consumers in relation to sustainability transition processes and wider systemic transformations. In contrast to the individualistic focus in much research on sustainable consumption, the embeddedness of consumption activities...... in wider social, economic and technological frameworks is emphasised. In particular, the chapter is inspired by practice theory and transition theory. First, various trends in consumption are outlined to highlight some of the challenges for sustainability transitions. Then, it is discussed how consumption...... patterns are shaped over time and what should be considered in sustainability strategies. While discussions on consumption often take their point of departure in the perspective of the individual and then zoom to the wider context, the present approach is the opposite. The outline starts with the basic...

  11. Sustainable Futures

    Science.gov (United States)

    Sustainable Futures is a voluntary program that encourages industry to use predictive models to screen new chemicals early in the development process and offers incentives to companies subject to TSCA section 5.

  12. Exposure to blue light during lunch break: effects on autonomic arousal and behavioral alertness.

    Science.gov (United States)

    Yuda, Emi; Ogasawara, Hiroki; Yoshida, Yutaka; Hayano, Junichiro

    2017-07-11

    Exposures to melanopsin-stimulating (melanopic) component-rich blue light enhance arousal level. We examined their effects in office workers. Eight healthy university office workers were exposed to blue and orange lights for 30 min during lunch break on different days. We compared the effects of light color on autonomic arousal level assessed by heart rate variability (HRV) and behavioral alertness by psychomotor vigilance tests (PVT). Heart rate was higher and high-frequency (HF, 0.150.45 Hz) power of HRV was lower during exposure to the blue light than to orange light. No significant difference with light color was observed, however, in any HRV indices during PVT or in PVT performance after light exposure. Exposure to blue light during lunch break, compared with that to orange light, enhances autonomic arousal during exposure, but has no sustained effect on autonomic arousal or behavioral alertness after exposure.

  13. Local Sustainability

    International Nuclear Information System (INIS)

    Carrizosa Umana, Julio

    1998-01-01

    The current polemic about the possibilities of sustainable development has led to a renovated interest for the topic of the sustainability of the communities and the local sustainability. In front of the global sustainability whose conditions have been exposed by systemic ecologists and for macro economists, the sustainability of specific places arises in the planet whose conditions are object of study of the ecology of landscapes, of the ecological economy, of the cultural anthropology, of the environmental sociology and naturally, of the integral environmentalism. In this discussion the Colombian case charges unusual interest to be one of the few countries of Latin America, where a very dense net of municipalities exists, each one with its urban helmet and with a position and some functions defined by the political constitution of the nation. This net of municipalities and of urban helmets it also constitutes net of alternative to the current macro-cephalic situation. As well as Bogota grew, in a hundred years, of less than a hundred thousand inhabitants to six million inhabitants, each one of these municipalities contains a potential of growth that depends on the characteristics of its ecological, social, economic and politic sustainability

  14. Autonomous power system intelligent diagnosis and control

    Science.gov (United States)

    Ringer, Mark J.; Quinn, Todd M.; Merolla, Anthony

    1991-01-01

    The Autonomous Power System (APS) project at NASA Lewis Research Center is designed to demonstrate the abilities of integrated intelligent diagnosis, control, and scheduling techniques to space power distribution hardware. Knowledge-based software provides a robust method of control for highly complex space-based power systems that conventional methods do not allow. The project consists of three elements: the Autonomous Power Expert System (APEX) for fault diagnosis and control, the Autonomous Intelligent Power Scheduler (AIPS) to determine system configuration, and power hardware (Brassboard) to simulate a space based power system. The operation of the Autonomous Power System as a whole is described and the responsibilities of the three elements - APEX, AIPS, and Brassboard - are characterized. A discussion of the methodologies used in each element is provided. Future plans are discussed for the growth of the Autonomous Power System.

  15. Anesthesia Management in Diabetic Cardiovascular Autonomic Neuropathy

    Directory of Open Access Journals (Sweden)

    Feride Karacaer

    2016-06-01

    Full Text Available Cardiovascular autonomic neuropathy is frequently observed in patients with diabetes mellitus and encompasses damage to the autonomic nerve fibers, resulting in abnormalities in heart rate control and vascular dynamics. There is an increased mortality and morbidity rate among these patients. A series of cardiovascular reflex tests known as Ewing's battery tests are used for diagnosis cardiac autonomic neuropathy and provide valuable information to the clinical assessment of these patients. As anesthesia has a major influence on perioperative autonomic function, the interplay between cardiovascular autonomic neuropathy and anesthesia may result in unexpected haemodynamic instability during surgery and postoperative recovery. A comprehensive preoperative assessment and perioperative cautious monitoring are necessary for successful anesthesia management. [Archives Medical Review Journal 2016; 25(2.000: 140-151

  16. Ultrastructural changes during spermatogenesis, biochemical and hormonal evidences of testicular toxicity caused by TBT in freshwater prawn Macrobrachium rosenbergii (De Man, 1879).

    Science.gov (United States)

    Revathi, Peranandam; Iyapparaj, Palanisamy; Vasanthi, Lourduraj Arockia; Munuswamy, Natesan; Krishnan, Muthukalingan

    2014-10-01

    The present investigation documents the impact of tributyltin (TBT) on the ultrastructural variation of spermatogenesis in freshwater prawn Macrobrachium rosenbergii. The environmentally realistic concentration of TBT can cause damages to the endocrine and reproductive physiology of crustaceans. In this context, three concentrations viz. 10, 100, and 1000 ng/L were selected and exposed to prawns for 90 days. The TBT exposed prawn exhibited decrease the reproductive activity as evidenced by sperm count and sperm length compared to control. Histopathological results revealed the retarded testicular development, abnormal structure of seminiferous tubule, decrease in the concentration of spermatozoa, diminution of seminiferous tubule membrane, abundance of spermatocytes and vacuolation in testis of treated prawns. Ultrastructural study also confirmed the impairment of spermatogenesis in treated prawns. Furthermore, radioimmunoassay (RIA) clearly documented the reduction of testosterone level in TBT exposed groups. Thus, TBT substantially reduced the level of male sex hormone as well as biochemical constituents which ultimately led to impairment of spermatogenesis in the freshwater male prawn M. rosenbergii. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

  17. A noncoding RNA containing a SINE-B1 motif associates with meiotic metaphase chromatin and has an indispensable function during spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Ryusuke Nakajima

    Full Text Available A search for early response genes that are activated following germ cell induction from mouse embryonic stem cells in vitro led us to the isolation of a long noncoding RNA that contains a SINE (short interspersed element-B1F motif that was named R53. In situ hybridization and northern blot analyses revealed that the R53 subfragment RNA bears a B1F motif, is processed from the primary transcript, is expressed in adult testis and is predominantly localized in meiotic metaphase chromatin during spermatogenesis. Recent studies of chromosome-associated RNAs have explored novel functions of noncoding RNAs. Specifically, chromosome-bound noncoding RNAs function not only as structural components of chromosome but also as scaffolds that recruit epigenetic modulators for transcriptional regulation, and they are dynamically rearranged during the cell cycle. However, few studies have explored meiotic chromatin; thus, R53 RNA appears to be the first long noncoding RNA to be tightly associated with the metaphase chromatin during spermatogenesis. Furthermore, R53 knockdown using a lentivirus-mediated RNAi injected into mouse testis and organ culture of the fragments revealed a remarkable reduction in postmeiotic cells and irregular up-regulation of several postmeiotic genes, which suggests the possibility that the SINE-B1-derived noncoding RNA R53 plays an indispensable role in the transcriptional regulation of key spermatogenesis genes.

  18. Current challenges in autonomous driving

    Science.gov (United States)

    Barabás, I.; Todoruţ, A.; Cordoş, N.; Molea, A.

    2017-10-01

    Nowadays the automotive industry makes a quantum shift to a future, where the driver will have smaller and smaller role in driving his or her vehicle ending up being totally excluded. In this paper, we have investigated the different levels of driving automatization, the prospective effects of these new technologies on the environment and traffic safety, the importance of regulations and their current state, the moral aspects of introducing these technologies and the possible scenarios of deploying the autonomous vehicles. We have found that the self-driving technologies are facing many challenges: a) They must make decisions faster in very diverse conditions which can include many moral dilemmas as well; b) They have an important potential in reducing the environmental pollution by optimizing their routes, driving styles by communicating with other vehicles, infrastructures and their environment; c) There is a considerable gap between the self-drive technology level and the current regulations; fortunately, this gap shows a continuously decreasing trend; d) In case of many types of imminent accidents management there are many concerns about the ability of making the right decision. Considering that this field has an extraordinary speed of development, our study is up to date at the submission deadline. Self-driving technologies become increasingly sophisticated and technically accessible, and in some cases, they can be deployed for commercial vehicles as well. According to the current stage of research and development, it is still unclear how the self-driving technologies will be able to handle extreme and unexpected events including their moral aspects. Since most of the traffic accidents are caused by human error or omission, it is expected that the emergence of the autonomous technologies will reduce these accidents in their number and gravity, but the very few currently available test results have not been able to scientifically underpin this issue yet. The

  19. From ecological houses to sustainable cities

    DEFF Research Database (Denmark)

    Lauring, Michael

    2010-01-01

      Decades of Danish architects are educated in the Beaux-arts tradition putting art and aesthetics above techniques and hard knowledge. This has influenced the development of environmental and sustainable architecture, of which the article gives a brief survey covering the period from the first oil...... crisis in 1973 to present day also seen in relation to resource, political and cultural preconditions. The article shows, how sustainability forces architects to reintegrate techniques and urban aspects as crucial parts of design considerations, thus questioning artificial and autonomous approaches...

  20. Sleep in trigeminal autonomic cephalagias

    DEFF Research Database (Denmark)

    Barløse, Mads; Lund, Nunu; Jensen, Rigmor Højland

    2014-01-01

    PURPOSE OF REVIEW: Sleep and cluster headache (CH) are believed to be interconnected but the precise relation to the other trigeminal autonomic cephalalgias (TACs) is uncertain and complex. A better understanding of these relations may eventually lead to a clarification of the underlying mechanisms...... and eventually to more effective therapeutic regimens. This review aims to evaluate the existing literature on the subject of TACs and sleep. An association between episodic CH and distinct macrostructural sleep phases, especially the relation to rapid eye movement (REM) sleep, has been described in some older...... studies but could not be confirmed in other, more recent studies. Investigations into the microstructure of sleep in these patients are lacking. Only a few case reports exist on the relation between sleep and other TACs. SUMMARY: Recent studies do not find an association between CH and REM sleep. One...

  1. Autonomous Medical Care for Exploration

    Science.gov (United States)

    Johnson-Throop, Kathy A.; Polk, J. D.; Hines, John W.; Nall, Marsha M.

    2005-01-01

    The goal of Autonomous Medical Care (AMC) is to ensure a healthy, well-performing crew which is a primary need for exploration. The end result of this effort will be the requirements and design for medical systems for the CEV, lunar operations, and Martian operations as well as a ground-based crew health optimization plan. Without such systems, we increase the risk of medical events occurring during a mission and we risk being unable to deal with contingencies of illness and injury, potentially threatening mission success. AMC has two major components: 1) pre-flight crew health optimization and 2) in-flight medical care. The goal of pre-flight crew health optimization is to reduce the risk of illness occurring during a mission by primary prevention and prophylactic measures. In-flight autonomous medical care is the capability to provide medical care during a mission with little or no real-time support from Earth. Crew medical officers or other crew members provide routine medical care as well as medical care to ill or injured crew members using resources available in their location. Ground support becomes telemedical consultation on-board systems/people collect relevant data for ground support to review. The AMC system provides capabilities to incorporate new procedures and training and advice as required. The on-board resources in an autonomous system should be as intelligent and integrated as is feasible, but autonomous does not mean that no human will be involved. The medical field is changing rapidly, and so a challenge is to determine which items to pursue now, which to leverage other efforts (e.g. military), and which to wait for commercial forces to mature. Given that what is used for the CEV or the Moon will likely be updated before going to Mars, a critical piece of the system design will be an architecture that provides for easy incorporation of new technologies into the system. Another challenge is to determine the level of care to provide for each

  2. Autonomous Infrastructure for Observatory Operations

    Science.gov (United States)

    Seaman, R.

    This is an era of rapid change from ancient human-mediated modes of astronomical practice to a vision of ever larger time domain surveys, ever bigger "big data", to increasing numbers of robotic telescopes and astronomical automation on every mountaintop. Over the past decades, facets of a new autonomous astronomical toolkit have been prototyped and deployed in support of numerous space missions. Remote and queue observing modes have gained significant market share on the ground. Archives and data-mining are becoming ubiquitous; astroinformatic techniques and virtual observatory standards and protocols are areas of active development. Astronomers and engineers, planetary and solar scientists, and researchers from communities as diverse as particle physics and exobiology are collaborating on a vast range of "multi-messenger" science. What then is missing?

  3. Design of Autonomous Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Tadahiro Hyakudome

    2011-03-01

    Full Text Available There are concerns about the impact that global warming will have on our environment, and which will inevitably result in expanding deserts and rising water levels. While a lot of underwater vehicles are utilized, AUVs (Autonomous Underwater Vehicle were considered and chosen, as the most suitable tool for conduction survey concerning these global environmental problems. AUVs can comprehensive survey because the vehicle does not have to be connected to the support vessel by tether cable. When such underwater vehicles are made, it is necessary to consider about the following things. 1 Seawater and Water Pressure Environment, 2 Sink, 3 There are no Gas or Battery Charge Stations, 4 Global Positioning System cannot use, 5 Radio waves cannot use. In the paper, outline of above and how deal about it are explained.

  4. Assessing and monitoring cryptic reef diversity of colonizing marine invertebrates across the U.S.-affiliated islands and atolls in the Pacific since 2008 using the Autonomous Reef Monitoring Structure (ARMS) method

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term program for sustainable management and conservation of coral reef ecosystems, from 2008, Autonomous Reef Monitoring Structures (ARMS) have...

  5. Pacific Reef Assessment and Monitoring Program: Assessing and Monitoring Cryptic Reef Diversity of Colonizing Marine Invertebrates using Autonomous Reef Monitoring Structures (ARMS) Deployed at Coral Reef Sites across the U.S. Pacific from 2008 to 2012

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term program for sustainable management and conservation of coral reef ecosystems, from 2008, Autonomous Reef Monitoring Structures (ARMS) have...

  6. Radar based autonomous sensor module

    Science.gov (United States)

    Styles, Tim

    2016-10-01

    Most surveillance systems combine camera sensors with other detection sensors that trigger an alert to a human operator when an object is detected. The detection sensors typically require careful installation and configuration for each application and there is a significant burden on the operator to react to each alert by viewing camera video feeds. A demonstration system known as Sensing for Asset Protection with Integrated Electronic Networked Technology (SAPIENT) has been developed to address these issues using Autonomous Sensor Modules (ASM) and a central High Level Decision Making Module (HLDMM) that can fuse the detections from multiple sensors. This paper describes the 24 GHz radar based ASM, which provides an all-weather, low power and license exempt solution to the problem of wide area surveillance. The radar module autonomously configures itself in response to tasks provided by the HLDMM, steering the transmit beam and setting range resolution and power levels for optimum performance. The results show the detection and classification performance for pedestrians and vehicles in an area of interest, which can be modified by the HLDMM without physical adjustment. The module uses range-Doppler processing for reliable detection of moving objects and combines Radar Cross Section and micro-Doppler characteristics for object classification. Objects are classified as pedestrian or vehicle, with vehicle sub classes based on size. Detections are reported only if the object is detected in a task coverage area and it is classified as an object of interest. The system was shown in a perimeter protection scenario using multiple radar ASMs, laser scanners, thermal cameras and visible band cameras. This combination of sensors enabled the HLDMM to generate reliable alerts with improved discrimination of objects and behaviours of interest.

  7. Autonomous caregiver following robotic wheelchair

    Science.gov (United States)

    Ratnam, E. Venkata; Sivaramalingam, Sethurajan; Vignesh, A. Sri; Vasanth, Elanthendral; Joans, S. Mary

    2011-12-01

    In the last decade, a variety of robotic/intelligent wheelchairs have been proposed to meet the need in aging society. Their main research topics are autonomous functions such as moving toward some goals while avoiding obstacles, or user-friendly interfaces. Although it is desirable for wheelchair users to go out alone, caregivers often accompany them. Therefore we have to consider not only autonomous functions and user interfaces but also how to reduce caregivers' load and support their activities in a communication aspect. From this point of view, we have proposed a robotic wheelchair moving with a caregiver side by side based on the MATLAB process. In this project we discussing about robotic wheel chair to follow a caregiver by using a microcontroller, Ultrasonic sensor, keypad, Motor drivers to operate robot. Using camera interfaced with the DM6437 (Davinci Code Processor) image is captured. The captured image are then processed by using image processing technique, the processed image are then converted into voltage levels through MAX 232 level converter and given it to the microcontroller unit serially and ultrasonic sensor to detect the obstacle in front of robot. In this robot we have mode selection switch Automatic and Manual control of robot, we use ultrasonic sensor in automatic mode to find obstacle, in Manual mode to use the keypad to operate wheel chair. In the microcontroller unit, c language coding is predefined, according to this coding the robot which connected to it was controlled. Robot which has several motors is activated by using the motor drivers. Motor drivers are nothing but a switch which ON/OFF the motor according to the control given by the microcontroller unit.

  8. Abnormal spermatogenesis following sodium fluoride exposure is associated with the downregulation of CREM and ACT in the mouse testis.

    Science.gov (United States)

    Wang, Chong; Chen, Yan; Manthari, Ram Kumar; Wang, Jundong

    2018-04-01

    cAMP response element modulator (CREM) is involved in regulating gene expression in normal spermatogenesis. The transcriptional activity of CREM is partly regulated by activator of CREM in the testis (ACT). To investigate the effects of different concentrations of sodium fluoride (NaF) on the gene and protein expression of CREM and ACT in the mouse testis, sexually mature male Kunming mice were exposed to 50, 100, or 150 mg/L NaF in their drinking water for 90 days. NaF reduced the sperm count and viability and increased the percentage of malformed sperm in a dose-dependent manner. The mRNA expression of CREM and ACT was markedly downregulated in the NaF-treated groups. Furthermore, immunohistochemistry revealed that CREM and ACT proteins were decreased significantly in the 50, 100, and 150 mg/L NaF-treated groups compared to the control group. These findings indicate that the decreased gene and protein expression of CREM and ACT in the testis is associated with an impairment of reproductive functions by NaF.

  9. Effects of environmental radiation on testes and spermatogenesis in wild large Japanese field mice (Apodemus speciosus) from Fukushima.

    Science.gov (United States)

    Okano, Tsukasa; Ishiniwa, Hiroko; Onuma, Manabu; Shindo, Junji; Yokohata, Yasushi; Tamaoki, Masanori

    2016-03-23

    The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident that occurred after the Great East Japan Earthquake in March 2011 released large quantities of radionuclides to the environment. The long-term effects of radioactive cesium (Cs) on biota are of particular concern. We investigated the accumulation of radioactive Cs derived from the FDNPP accident, and chronic effects of environmental radionuclides on male reproduction, in the large Japanese field mouse (Apodemus speciosus). In 2013 and 2014, wild mice were captured at 2 sites in Fukushima Prefecture and at 2 control sites that were distant from Fukushima. Although the median concentrations of (134)Cs and (137)Cs in the mice from Fukushima exceeded 4,000 Bq/kg, there were no significant differences in the apoptotic cell frequencies or the frequencies of morphologically abnormal sperm among the capture sites. Thus, we conclude that radiation did not cause substantial male subfertility in Fukushima during 2013 and 2014, and radionuclide pollution levels in the study sites would not be detrimental to spermatogenesis of the wild mice in Fukushima.

  10. A tubulin alpha 8 mouse knockout model indicates a likely role in spermatogenesis but not in brain development.

    Directory of Open Access Journals (Sweden)

    Christine P Diggle

    Full Text Available Tubulin alpha 8 (Tuba8 is the most divergent member of the highly conserved alpha tubulin family, and uniquely lacks two key post-translational modification sites. It is abundantly expressed in testis and muscle, with lower levels in the brain. We previously identified homozygous hypomorphic TUBA8 mutations in human subjects with a polymicrogyria (PMG syndrome, suggesting its involvement in development of the cerebral cortex. We have now generated and characterized a Tuba8 knockout mouse model. Homozygous mice were confirmed to lack Tuba8 protein in the testis, but did not display PMG and appeared to be neurologically normal. In response to this finding, we re-analyzed the human PMG subjects using whole exome sequencing. This resulted in identification of an additional homozygous loss-of-function mutation in SNAP29, suggesting that SNAP29 deficiency, rather than TUBA8 deficiency, may underlie most or all of the neurodevelopmental anomalies in these subjects. Nonetheless, in the mouse brain, Tuba8 specifically localised to the cerebellar Purkinje cells, suggesting that the human mutations may affect or modify motor control. In the testis, Tuba8 localisation was cell-type specific. It was restricted to spermiogenesis with a strong acrosomal localization that was gradually replaced by cytoplasmic distribution and was absent from spermatozoa. Although the knockout mice were fertile, the localisation pattern indicated that Tuba8 may have a role in spermatid development during spermatogenesis, rather than as a component of the mature microtubule-rich flagellum itself.

  11. A STUDY ON CARDIOVASCULAR AUTONOMIC FUNCTIONS IN CAREGIVERS OF STROKE PATIENTS

    Directory of Open Access Journals (Sweden)

    Ghouse Mubarak

    2017-08-01

    Full Text Available BACKGROUND Stroke (cerebrovascular accident is an important cause of disability in countries like India and longterm care of these bedridden patients is usually undertaken by the family members. A caregiver is a person who takes responsibility for those who cannot completely care for themselves. Taking care of a chronically ill member in the family usually causes stress to the caregiver causing disturbances in the autonomic function. Thus, the present study is undertaken to find out the effect of longterm caregiving on cardiovascular autonomic functions in a caregiver. MATERIALS AND METHODS 57 caregivers of post-stroke bedridden patients, both male and female, were included in this longitudinal study. Parasympathetic activity was assessed by observing the heart rate changes to immediate standing from lying down position, heart rate changes during deep breathing and heart rate changes during Valsalva manoeuvre. Sympathetic activity was assessed by observing blood pressure changes on immediate standing from lying down position and blood pressure changes during sustained hand grip. RESULTS The results of the present study showed statistically significant decrease in Valsalva ratio, decrease in the heart rate following deep breathing and statistically significant increase in systolic blood pressure in response to immediate standing suggestive of autonomic imbalance. CONCLUSION Our findings suggest that longterm caregiving is accompanied by dysfunction of the cardiac autonomic nervous system, and these individuals are more prone to autonomic neuropathy.

  12. Insights into the clinical and functional significance of cardiac autonomic dysfunction in Chagas disease

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Junqueira Junior

    2012-04-01

    Full Text Available INTRODUCTION: Exclusive or associated lesions in various structures of the autonomic nervous system occur in the chronic forms of Chagas disease. In the indeterminate form, the lesions are absent or mild, whereas in the exclusive or combined heart and digestive disease forms, they are often more pronounced. Depending on their severity these lesions can result mainly in cardiac parasympathetic dysfunction but also in sympathetic dysfunction of variable degrees. Despite the key autonomic effect on cardiovascular functioning, the pathophysiological and clinical significance of the cardiac autonomic dysfunction in Chagas disease remains unknown. METHODS: Review of data on the cardiac autonomic dysfunction in Chagas disease and their potential consequences, and considerations supporting the possible relationship between this disturbance and general or cardiovascular clinical and functional adverse outcomes. RESULTS: We hypothesise that possible consequences that cardiac dysautonomia might variably occasion or predispose in Chagas disease include: transient or sustained arrhythmias, sudden cardiac death, adverse overall and cardiovascular prognosis with enhanced morbidity and mortality, an inability of the cardiovascular system to adjust to functional demands and/or respond to internal or external stimuli by adjusting heart rate and other hemodynamic variables, and immunomodulatory and cognitive disturbances. CONCLUSIONS: Impaired cardiac autonomic modulation in Chagas disease might not be a mere epiphenomenon without significance. Indirect evidences point for a likely important role of this alteration as a primary predisposing or triggering cause or mediator favouring the development of subtle or evident secondary cardiovascular functional disturbances and clinical consequences, and influencing adverse outcomes.

  13. Current challenges in autonomous vehicle development

    Science.gov (United States)

    Connelly, J.; Hong, W. S.; Mahoney, R. B., Jr.; Sparrow, D. A.

    2006-05-01

    The field of autonomous vehicles is a rapidly growing one, with significant interest from both government and industry sectors. Autonomous vehicles represent the intersection of artificial intelligence (AI) and robotics, combining decision-making with real-time control. Autonomous vehicles are desired for use in search and rescue, urban reconnaissance, mine detonation, supply convoys, and more. The general adage is to use robots for anything dull, dirty, dangerous or dumb. While a great deal of research has been done on autonomous systems, there are only a handful of fielded examples incorporating machine autonomy beyond the level of teleoperation, especially in outdoor/complex environments. In an attempt to assess and understand the current state of the art in autonomous vehicle development, a few areas where unsolved problems remain became clear. This paper outlines those areas and provides suggestions for the focus of science and technology research. The first step in evaluating the current state of autonomous vehicle development was to develop a definition of autonomy. A number of autonomy level classification systems were reviewed. The resulting working definitions and classification schemes used by the authors are summarized in the opening sections of the paper. The remainder of the report discusses current approaches and challenges in decision-making and real-time control for autonomous vehicles. Suggested research focus areas for near-, mid-, and long-term development are also presented.

  14. Sustainability Evaluation.

    Science.gov (United States)

    Stichnothe, Heinz

    2017-03-17

    The long-term substitution of fossil resources can only be achieved through a bio-based economy, with biorefineries and bio-based products playing a major role. However, it is important to assess the implications of the transition to a bio-based economy. Life cycle-based sustainability assessment is probably the most suitable approach to quantify impacts and to identify trade-offs at multiple levels. The extended utilisation of biomass can cause land use change and affect food security of the most vulnerable people throughout the world. Although this is mainly a political issue and governments should be responsible, the responsibility is shifted to companies producing biofuels and other bio-based products. Organic wastes and lignocellulosic biomass are considered to be the preferred feedstock for the production of bio-based products. However, it is unlikely that a bio-based economy can rely only on organic wastes and lignocellulosic biomass.It is crucial to identify potential problems related to socio-economic and environmental issues. Currently there are many approaches to the sustainability of bio-based products, both quantitative and qualitative. However, results of different calculation methods are not necessarily comparable and can cause confusion among decision-makers, stakeholders and the public.Hence, a harmonised, globally agreed approach would be the best solution to secure sustainable biomass/biofuels/bio-based chemicals production and trade, and to avoid indirect effects (e.g. indirect land use change). However, there is still a long way to go.Generally, the selection of suitable indicators that serve the purpose of sustainability assessment is very context-specific. Therefore, it is recommended to use a flexible and modular approach that can be adapted to various purposes. A conceptual model for the selection of sustainability indicators is provided that facilitates identifying suitable sustainability indicators based on relevance and significance in a

  15. Stabilizing Sustainability

    DEFF Research Database (Denmark)

    Reitan Andersen, Kirsti

    on the textile and fashion industry, one of the world’s most polluting industries and an industry to some degree notorious for leading the ‘race to the bottom’ in global labour standards. Despite being faced with increasing demands to practise sustainability, most textile and fashion companies continue to fail...... undertake the changes that are necessary to achieve greater sustainability—or at best continue to struggle in a globalized and highly interconnected industry to implement the necessary changes. In light of this failure, this thesis investigates how organizations can change towards practising sustainability...

  16. Roundtabling Sustainability

    DEFF Research Database (Denmark)

    Ponte, Stefano

    2014-01-01

    councils’ and ‘sustainability roundtables’ and have been designed around a set of institutional features seeking to establish legitimacy, fend off possible criticism, and ‘sell’ certifications to potential users. The concept of ‘roundtabling’ emphasizes the fitting a variety of commodity...... extent these expectations are being met through the comparative case study of two sustainability certifications in the biofuel industry – in the context of a wider set of experiences in the agro-food and forestry sectors. I show that ‘roundtabling’ entails an ever more complex web of governance systems...

  17. Autonomous Demand Response for Primary Frequency Regulation

    Energy Technology Data Exchange (ETDEWEB)

    Donnelly, Matt [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Trudnowski, Daniel J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mattix, S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dagle, Jeffery E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-01-01

    The research documented within this report examines the use of autonomous demand response to provide primary frequency response in an interconnected power grid. The work builds on previous studies in several key areas: it uses a large realistic model (i.e., the interconnection of the western United States and Canada); it establishes a set of metrics that can be used to assess the effectiveness of autonomous demand response; and it independently adjusts various parameters associated with using autonomous demand response to assess effectiveness and to examine possible threats or vulnerabilities associated with the technology.

  18. Autonomous Bicycle: The First Self Balanced Ride

    OpenAIRE

    Ånnestad, Dag Christian

    2011-01-01

    The idea of an autonomous bicycle originates from Jens G. Balchen who wanted to make an unmanned autonomous bicycle. The idea was picked up by Amund Skavhaug who extended the idea with the concept of using an inverted pendulum to simulate a leaning rider. The previous attempts to develop a bicycle capable of performing an autonomous ride has so far all ended in failure. The main reason for the Department of Engineering Cybernetics is to develop such a bicycle is for use in recruitment and mot...

  19. Development of a Commercially Viable, Modular Autonomous Robotic Systems for Converting any Vehicle to Autonomous Control

    Science.gov (United States)

    Parish, David W.; Grabbe, Robert D.; Marzwell, Neville I.

    1994-01-01

    A Modular Autonomous Robotic System (MARS), consisting of a modular autonomous vehicle control system that can be retrofit on to any vehicle to convert it to autonomous control and support a modular payload for multiple applications is being developed. The MARS design is scalable, reconfigurable, and cost effective due to the use of modern open system architecture design methodologies, including serial control bus technology to simplify system wiring and enhance scalability. The design is augmented with modular, object oriented (C++) software implementing a hierarchy of five levels of control including teleoperated, continuous guidepath following, periodic guidepath following, absolute position autonomous navigation, and relative position autonomous navigation. The present effort is focused on producing a system that is commercially viable for routine autonomous patrolling of known, semistructured environments, like environmental monitoring of chemical and petroleum refineries, exterior physical security and surveillance, perimeter patrolling, and intrafacility transport applications.

  20. Sustainable finance

    NARCIS (Netherlands)

    dr. Margreet F. Boersma-de Jong

    2012-01-01

    Presentation for Springschool of Strategy, University of Groningen, 10 October 2012. The role of CSR is to stimulate ethical behaviour, and as a result, mutual trust in society. Advantage of CSR for the company and the evolution of CSR. From CSR to Sustainable Finance: how does CSR influence

  1. Generous sustainability

    NARCIS (Netherlands)

    Gerlagh, Reyer

    I define "generous sustainability" as a combination of two conditions: neither instantaneous maximin utility nor attainable maximin utility should decrease over time. I provide a formal definition and study applications to a Climate Economy with bounded and with unbounded growth. Generosity is shown

  2. Sustainable machining

    CERN Document Server

    2017-01-01

    This book provides an overview on current sustainable machining. Its chapters cover the concept in economic, social and environmental dimensions. It provides the reader with proper ways to handle several pollutants produced during the machining process. The book is useful on both undergraduate and postgraduate levels and it is of interest to all those working with manufacturing and machining technology.

  3. Sustainability reporting

    NARCIS (Netherlands)

    Kolk, A.

    2005-01-01

    This article gives an overview of developments in sustainability (also sometimes labelled corporate social responsibility) reporting. It The article will first briefly indicate how accountability on social and environmental issues started, already in the 1970s when social reports were published.

  4. Exergy sustainability.

    Energy Technology Data Exchange (ETDEWEB)

    Robinett, Rush D. III (.; ); Wilson, David Gerald; Reed, Alfred W.

    2006-05-01

    Exergy is the elixir of life. Exergy is that portion of energy available to do work. Elixir is defined as a substance held capable of prolonging life indefinitely, which implies sustainability of life. In terms of mathematics and engineering, exergy sustainability is defined as the continuous compensation of irreversible entropy production in an open system with an impedance and capacity-matched persistent exergy source. Irreversible and nonequilibrium thermodynamic concepts are combined with self-organizing systems theories as well as nonlinear control and stability analyses to explain this definition. In particular, this paper provides a missing link in the analysis of self-organizing systems: a tie between irreversible thermodynamics and Hamiltonian systems. As a result of this work, the concept of ''on the edge of chaos'' is formulated as a set of necessary and sufficient conditions for stability and performance of sustainable systems. This interplay between exergy rate and irreversible entropy production rate can be described as Yin and Yang control: the dialectic synthesis of opposing power flows. In addition, exergy is shown to be a fundamental driver and necessary input for sustainable systems, since exergy input in the form of power is a single point of failure for self-organizing, adaptable systems.

  5. Sustainable Buildings

    DEFF Research Database (Denmark)

    Tommerup, Henrik M.; Elle, Morten

    The scientific community agrees that: all countries must drastically and rapidly reduce their CO2 emissions and that energy efficient houses play a decisive role in this. The general attitude at the workshop on Sustainable Buildings was that we face large and serious climate change problems...

  6. Sustainable processing

    DEFF Research Database (Denmark)

    Kristensen, Niels Heine

    2004-01-01

    Kristensen_NH and_Beck A: Sustainable processing. In Otto Schmid, Alexander Beck and Ursula Kretzschmar (Editors) (2004): Underlying Principles in Organic and "Low-Input Food" Processing - Literature Survey. Research Institute of Organic Agriculture FiBL, CH-5070 Frick, Switzerland. ISBN 3-906081-58-3...

  7. Sustainable Procurement

    DEFF Research Database (Denmark)

    Telles, Pedro; Ølykke, Grith Skovgaard

    2017-01-01

    and within it how sustainable requirements have increased the level of compliance required, particularly regulatory compliance. Compliance was already present in previous EU public procurement frameworks, but its extent on Directive 2014/24/EU leads the authors to consider the current legal framework...

  8. Sustainable Sizing.

    Science.gov (United States)

    Robinette, Kathleen M; Veitch, Daisy

    2016-08-01

    To provide a review of sustainable sizing practices that reduce waste, increase sales, and simultaneously produce safer, better fitting, accommodating products. Sustainable sizing involves a set of methods good for both the environment (sustainable environment) and business (sustainable business). Sustainable sizing methods reduce (1) materials used, (2) the number of sizes or adjustments, and (3) the amount of product unsold or marked down for sale. This reduces waste and cost. The methods can also increase sales by fitting more people in the target market and produce happier, loyal customers with better fitting products. This is a mini-review of methods that result in more sustainable sizing practices. It also reviews and contrasts current statistical and modeling practices that lead to poor fit and sizing. Fit-mapping and the use of cases are two excellent methods suited for creating sustainable sizing, when real people (vs. virtual people) are used. These methods are described and reviewed. Evidence presented supports the view that virtual fitting with simulated people and products is not yet effective. Fit-mapping and cases with real people and actual products result in good design and products that are fit for person, fit for purpose, with good accommodation and comfortable, optimized sizing. While virtual models have been shown to be ineffective for predicting or representing fit, there is an opportunity to improve them by adding fit-mapping data to the models. This will require saving fit data, product data, anthropometry, and demographics in a standardized manner. For this success to extend to the wider design community, the development of a standardized method of data collection for fit-mapping with a globally shared fit-map database is needed. It will enable the world community to build knowledge of fit and accommodation and generate effective virtual fitting for the future. A standardized method of data collection that tests products' fit methodically

  9. Autonomic Dysfunction in Patients with Mild to Moderate Alzheimer's Disease

    DEFF Research Database (Denmark)

    Jensen-Dahm, Christina; Waldemar, Gunhild; Staehelin Jensen, Troels

    2015-01-01

    BACKGROUND: Autonomic function has received little attention in Alzheimer's disease (AD). AD pathology has an impact on brain regions which are important for central autonomic control, but it is unclear if AD is associated with disturbance of autonomic function. OBJECTIVE: To investigate autonomic...

  10. Autonomous Operations Design Guidelines for Flight Hardware

    Data.gov (United States)

    National Aeronautics and Space Administration — SSC experimentally modified an autonomous operations flexible system suite developed for a ground application for a flight system under development by JSC. The...

  11. Autonomous Operations System: Development and Application

    Science.gov (United States)

    Toro Medina, Jaime A.; Wilkins, Kim N.; Walker, Mark; Stahl, Gerald M.

    2016-01-01

    Autonomous control systems provides the ability of self-governance beyond the conventional control system. As the complexity of mechanical and electrical systems increases, there develops a natural drive for developing robust control systems to manage complicated operations. By closing the bridge between conventional automated systems to knowledge based self-awareness systems, nominal control of operations can evolve into relying on safe critical mitigation processes to support any off-nominal behavior. Current research and development efforts lead by the Autonomous Propellant Loading (APL) group at NASA Kennedy Space Center aims to improve cryogenic propellant transfer operations by developing an automated control and health monitoring system. As an integrated systems, the center aims to produce an Autonomous Operations System (AOS) capable of integrating health management operations with automated control to produce a fully autonomous system.

  12. Cislunar Autonomous Positioning System (CAPS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Recent efforts led by the PI of this proposal have studied the benefits of a satellite navigation technique known as Linked Autonomous Interplanetary Satellite Orbit...

  13. Computer vision for an autonomous mobile robot

    CSIR Research Space (South Africa)

    Withey, Daniel J

    2015-10-01

    Full Text Available Computer vision systems are essential for practical, autonomous, mobile robots – machines that employ artificial intelligence and control their own motion within an environment. As with biological systems, computer vision systems include the vision...

  14. Data Provisioning Systems for Autonomous Vehicles

    National Research Council Canada - National Science Library

    Varaiya, Pravin

    1999-01-01

    This project is part of a portfolio comprising four other projects to investigate the possibility of operating a collection of intelligent autonomous agents so that the collection can undertakes complex missions...

  15. A Primer on Autonomous Aerial Vehicle Design.

    Science.gov (United States)

    Coppejans, Hugo H G; Myburgh, Herman C

    2015-12-02

    There is a large amount of research currently being done on autonomous micro-aerial vehicles (MAV), such as quadrotor helicopters or quadcopters. The ability to create a working autonomous MAV depends mainly on integrating a simultaneous localization and mapping (SLAM) solution with the rest of the system. This paper provides an introduction for creating an autonomous MAV for enclosed environments, aimed at students and professionals alike. The standard autonomous system and MAV automation are discussed, while we focus on the core concepts of SLAM systems and trajectory planning algorithms. The advantages and disadvantages of using remote processing are evaluated, and recommendations are made regarding the viability of on-board processing. Recommendations are made regarding best practices to serve as a guideline for aspirant MAV designers.

  16. Advisory and autonomous cooperative driving systems

    NARCIS (Netherlands)

    Broek, T.H.A. van den; Ploeg, J.; Netten, B.D.

    2011-01-01

    In this paper, the traffic efficiency of an advisory cooperative driving system, Advisory Acceleration Control is examined and compared to the efficiency of an autonomous cooperative driving system, Cooperative Adaptive Cruise Control. The algorithms and implementation thereof are explained. The

  17. Research Institute for Autonomous Precision Guided Systems

    National Research Council Canada - National Science Library

    Sforza, Pasquale

    2003-01-01

    The aim of this project is to leverage the manpower resources dedicated to basic research in technologies relevant to autonomous precision systems at the Air Force Research Laboratory Munitions Directorate (AFRL/MN...

  18. Autonomous Task Primitives for Complex Manipulation Operations

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this research effort is to enable robots to autonomously perform the complex manipulation tasks that are necessary to maintain a spacecraft. Robots, like...

  19. Acupuncture Effect and Central Autonomic Regulation

    Directory of Open Access Journals (Sweden)

    Qian-Qian Li

    2013-01-01

    Full Text Available Acupuncture is a therapeutic technique and part of traditional Chinese medicine (TCM. Acupuncture has clinical efficacy on various autonomic nerve-related disorders, such as cardiovascular diseases, epilepsy, anxiety and nervousness, circadian rhythm disorders, polycystic ovary syndrome (PCOS and subfertility. An increasing number of studies have demonstrated that acupuncture can control autonomic nerve system (ANS functions including blood pressure, pupil size, skin conductance, skin temperature, muscle sympathetic nerve activities, heart rate and/or pulse rate, and heart rate variability. Emerging evidence indicates that acupuncture treatment not only activates distinct brain regions in different kinds of diseases caused by imbalance between the sympathetic and parasympathetic activities, but also modulates adaptive neurotransmitter in related brain regions to alleviate autonomic response. This review focused on the central mechanism of acupuncture in modulating various autonomic responses, which might provide neurobiological foundations for acupuncture effects.

  20. Acupuncture effect and central autonomic regulation.

    Science.gov (United States)

    Li, Qian-Qian; Shi, Guang-Xia; Xu, Qian; Wang, Jing; Liu, Cun-Zhi; Wang, Lin-Peng

    2013-01-01

    Acupuncture is a therapeutic technique and part of traditional Chinese medicine (TCM). Acupuncture has clinical efficacy on various autonomic nerve-related disorders, such as cardiovascular diseases, epilepsy, anxiety and nervousness, circadian rhythm disorders, polycystic ovary syndrome (PCOS) and subfertility. An increasing number of studies have demonstrated that acupuncture can control autonomic nerve system (ANS) functions including blood pressure, pupil size, skin conductance, skin temperature, muscle sympathetic nerve activities, heart rate and/or pulse rate, and heart rate variability. Emerging evidence indicates that acupuncture treatment not only activates distinct brain regions in different kinds of diseases caused by imbalance between the sympathetic and parasympathetic activities, but also modulates adaptive neurotransmitter in related brain regions to alleviate autonomic response. This review focused on the central mechanism of acupuncture in modulating various autonomic responses, which might provide neurobiological foundations for acupuncture effects.

  1. Framework for Autonomous Optimization, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Phoenix Integration and MIT propose to create a novel autonomous optimization tool and application programming interface (API). The API will demonstrate the ability...

  2. A Primer on Autonomous Aerial Vehicle Design

    Directory of Open Access Journals (Sweden)

    Hugo H. G. Coppejans

    2015-12-01

    Full Text Available There is a large amount of research currently being done on autonomous micro-aerial vehicles (MAV, such as quadrotor helicopters or quadcopters. The ability to create a working autonomous MAV depends mainly on integrating a simultaneous localization and mapping (SLAM solution with the rest of the system. This paper provides an introduction for creating an autonomous MAV for enclosed environments, aimed at students and professionals alike. The standard autonomous system and MAV automation are discussed, while we focus on the core concepts of SLAM systems and trajectory planning algorithms. The advantages and disadvantages of using remote processing are evaluated, and recommendations are made regarding the viability of on-board processing. Recommendations are made regarding best practices to serve as a guideline for aspirant MAV designers.

  3. Interpersonal communication and issues for autonomous vehicles.

    Science.gov (United States)

    2017-06-01

    Interpersonal roadway communication is a vital component of the transportation system. Road users communicate to coordinate movement and increase roadway safety. Future autonomous vehicle research needs to account for the role of interpersonal roadwa...

  4. Autonomic symptoms in idiopathic REM behavior disorder

    DEFF Research Database (Denmark)

    Ferini-Strambi, Luigi; Oertel, Wolfgang; Dauvilliers, Yves

    2014-01-01

    to study the disorders of the autonomic nervous system in Parkinson's disease (PD) patients, the SCOPA-AUT, was administered to all the patients and controls. The SCOPA-AUT consists of 25 items assessing the following domains: gastrointestinal, urinary, cardiovascular, thermoregulatory, pupillomotor......Patients with idiopathic REM sleep behavior disorder (iRBD) are at very high risk of developing neurodegenerative synucleinopathies, which are disorders with prominent autonomic dysfunction. Several studies have documented autonomic dysfunction in iRBD, but large-scale assessment of autonomic...... symptoms has never been systematically performed. Patients with polysomnography-confirmed iRBD (318 cases) and controls (137 healthy volunteers and 181 sleep center controls with sleep diagnoses other than RBD) were recruited from 13 neurological centers in 10 countries from 2008 to 2011. A validated scale...

  5. Adaptive Sampling in Autonomous Marine Sensor Networks

    National Research Council Canada - National Science Library

    Eickstedt, Donald P

    2006-01-01

    ... oceanographic network scenario. This architecture has three major components, an intelligent, logical sensor that provides high-level environmental state information to a behavior-based autonomous vehicle control system, a new...

  6. Autonomous Training for Long-Term Spaceflight

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop the autonomous capability to intelligently select/generate practice scenarios in order to provide individually targeted crew training when...

  7. Future Autonomous and Automated Systems Testbed

    Data.gov (United States)

    National Aeronautics and Space Administration — Trust is the greatest obstacle to implementing greater autonomy and automation (A&A) in the human spaceflight program. The Future Autonomous and Automated...

  8. Semi-Autonomous Vehicle Project

    Science.gov (United States)

    Stewart, Christopher

    2016-01-01

    The primary objective this summer is "evaluating standards for wireless architecture for the internet of things". The Internet of Things is the network of physical objects or "things" embedded with electronics, software, sensors and network connectivity which enables these objects to collect and exchange data and make decisions based on said data. This was accomplished by creating a semi-autonomous vehicle that takes advantage of multiple sensors, cameras, and onboard computers and combined them with a mesh network which enabled communication across large distances with little to no interruption. The mesh network took advantage of what is known as DTN - Disruption Tolerant Networking which according to NASA is the new communications protocol that is "the first step towards interplanetary internet." The use of DTN comes from the fact that it will store information if an interruption in communications is detected and even forward that information via other relays within range so that the data is not lost. This translates well into the project because as the car moves further away from whatever is sending it commands (in this case a joystick), the information can still be forwarded to the car with little to no loss of information thanks to the mesh nodes around the driving area.

  9. Autonomous nutrient detection for water quality monitoring

    OpenAIRE

    Maher, Damien; Cleary, John; Cogan, Deirdre; Diamond, Dermot

    2012-01-01

    The ever increasing demand for real time environmental monitoring is currently being driven by strong legislative and societal drivers. Low cost autonomous environmental monitoring systems are required to meet this demand as current monitoring solutions are insufficient. This poster presents an autonomous nutrient analyser platform for water quality monitoring. Results from a field trial of the nutrient analyser are reported along with current work to expand the range of water quality targ...

  10. Non-autonomous bifurcation in impulsive systems

    Directory of Open Access Journals (Sweden)

    Marat Akhmet

    2013-12-01

    Full Text Available This is the first paper which considers non-autonomous bifurcations in impulsive differential equations. Impulsive generalizations of the non-autonomous pitchfork and transcritical bifurcation are discussed. We consider scalar differential equation with fixed moments of impulses. It is illustrated by means of certain systems how the idea of pullback attracting sets remains a fruitful concept in the impulsive systems. Basics of the theory are provided.

  11. Acupuncture Effect and Central Autonomic Regulation

    OpenAIRE

    Qian-Qian Li; Guang-Xia Shi; Qian Xu; Jing Wang; Cun-Zhi Liu; Lin-Peng Wang

    2013-01-01

    Acupuncture is a therapeutic technique and part of traditional Chinese medicine (TCM). Acupuncture has clinical efficacy on various autonomic nerve-related disorders, such as cardiovascular diseases, epilepsy, anxiety and nervousness, circadian rhythm disorders, polycystic ovary syndrome (PCOS) and subfertility. An increasing number of studies have demonstrated that acupuncture can control autonomic nerve system (ANS) functions including blood pressure, pupil size, skin conductance, skin temp...

  12. Autonomous Control System for Precise Orbit Maintenance

    OpenAIRE

    Aorpimai, Manop; Hashida, Yoshi; Palmer, Phil

    2000-01-01

    In this paper, we describe a closed-loop autonomous control system that enables orbit operations to be performed without the need of any ground segment. The growing availability of GPS receivers on satellites provides an excellent means for autonomous orbit determination and our work builds upon previous work on orbit determination algorithms developed here at Surrey. The orbit is described using a set of epicycle parameters which provide an analytic model of LEO orbits. The parameters in thi...

  13. Boule gene expression underpins the meiotic arrest in spermatogenesis in male rainbow trout (Oncorhynchus mykiss) exposed to DEHP and butachlor.

    Science.gov (United States)

    Ahmadivand, Sohrab; Farahmand, Hamid; Teimoori-Toolabi, Ladan; Mirvaghefi, Alireza; Eagderi, Soheil; Geerinckx, Tom; Shokrpoor, Sara; Rahmati-Holasoo, Hooman

    2016-01-01

    Boule, the ancestor of the DAZ (Deleted in AZoospermia) gene family, in most organisms is mainly involved in male meiosis. The present study investigates the effects of the plasticizer DEHP (50mg/kg body weight) and herbicide butachlor (0.39mg/L) on male rainbow trout (Oncorhynchus mykiss) for a 10-day period in two independent experiments. The results showed that plasma testosterone (T) concentrations were significantly lower in fish exposed to either DEHP or butachlor compared to the control fish (P0.05). In addition, no significant differences were found in the gonadosomatic index (GSI) in both DEHP and butachlor treatments (P>0.05). Histologically, testes of male trout in the control groups were well differentiated and filled with large numbers of cystic structures containing spermatozoa. In contrast, the testes of male trout contained mostly spermatocytes with few spermatozoa in both treated group, suggesting that DEHP and butachlor may inhibit the progression of meiosis. Also, boule gene expression was significantly lower in the testes of male trout affected by DEHP and butachlor in comparison with their control groups (Ptrout. Based on the results, the present study demonstrated that DEHP and butachlor can inhibit the progression of spermatogenesis in male trout, potentially by causing an arrest of meiosis, maybe due to down-regulation of boule gene expression through T and/or IGF1 via ERK1/2 signaling in T-independent pathways. In addition, these results confirmed that boule can be considered as a predictive marker to assess meiotic efficiency. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. The Human Element and Autonomous Ships

    Directory of Open Access Journals (Sweden)

    Sauli Ahvenjärvi

    2016-09-01

    Full Text Available The autonomous ship technology has become a “hot” topic in the discussion about more efficient, environmentally friendly and safer sea transportation solutions. The time is becoming mature for the introduction of commercially sensible solutions for unmanned and fully autonomous cargo and passenger ships. Safety will be the most interesting and important aspect in this development. The utilization of the autonomous ship technology will have many effects on the safety, both positive and negative. It has been announced that the goal is to make the safety of an unmanned ship better that the safety of a manned ship. However, it must be understood that the human element will still be present when fully unmanned ships are being used. The shore-based control of a ship contains new safety aspects and an interesting question will be the interaction of manned and unmanned ships in the same traffic area. The autonomous ship technology should therefore be taken into account on the training of seafarers. Also it should not be forgotten that every single control algorithm and rule of the internal decision making logic of the autonomously navigating ship has been designed and coded by a human software engineer. Thus the human element is present also in this point of the lifetime navigation system of the autonomous ship.

  15. Advancing Autonomous Operations for Deep Space Vehicles

    Science.gov (United States)

    Haddock, Angie T.; Stetson, Howard K.

    2014-01-01

    Starting in Jan 2012, the Advanced Exploration Systems (AES) Autonomous Mission Operations (AMO) Project began to investigate the ability to create and execute "single button" crew initiated autonomous activities [1]. NASA Marshall Space Flight Center (MSFC) designed and built a fluid transfer hardware test-bed to use as a sub-system target for the investigations of intelligent procedures that would command and control a fluid transfer test-bed, would perform self-monitoring during fluid transfers, detect anomalies and faults, isolate the fault and recover the procedures function that was being executed, all without operator intervention. In addition to the development of intelligent procedures, the team is also exploring various methods for autonomous activity execution where a planned timeline of activities are executed autonomously and also the initial analysis of crew procedure development. This paper will detail the development of intelligent procedures for the NASA MSFC Autonomous Fluid Transfer System (AFTS) as well as the autonomous plan execution capabilities being investigated. Manned deep space missions, with extreme communication delays with Earth based assets, presents significant challenges for what the on-board procedure content will encompass as well as the planned execution of the procedures.

  16. Autonomous power networks based power system

    International Nuclear Information System (INIS)

    Jokic, A.; Van den Bosch, P.P.J.

    2006-01-01

    This paper presented the concept of autonomous networks to cope with this increased complexity in power systems while enhancing market-based operation. The operation of future power systems will be more challenging and demanding than present systems because of increased uncertainties, less inertia in the system, replacement of centralized coordinating activities by decentralized parties and the reliance on dynamic markets for both power balancing and system reliability. An autonomous network includes the aggregation of networked producers and consumers in a relatively small area with respect to the overall system. The operation of an autonomous network is coordinated and controlled with one central unit acting as an interface between internal producers/consumers and the rest of the power system. In this study, the power balance problem and system reliability through provision of ancillary services was formulated as an optimization problem for the overall autonomous networks based power system. This paper described the simulation of an optimal autonomous network dispatching in day ahead markets, based on predicted spot prices for real power, and two ancillary services. It was concluded that large changes occur in a power systems structure and operation, most of them adding to the uncertainty and complexity of the system. The introduced concept of an autonomous power network-based power system was shown to be a realistic and consistent approach to formulate and operate a market-based dispatch of both power and ancillary services. 9 refs., 4 figs

  17. The role of autonomic testing in syncope.

    Science.gov (United States)

    Jones, Pearl K; Gibbons, Christopher H

    2014-09-01

    Syncope is a common presenting complaint in both the inpatient and outpatient settings. The main goals in the clinical evaluation of syncope are to identify an underlying etiology, to stratify risk and to guide plans for therapeutic intervention. Testing begins with an initial electrocardiogram to screen for any cardiac rhythm abnormalities. Heart rate variability to paced breathing provides a standard measure of cardiac parasympathetic function and offers clues towards an autonomic cause of syncope. A Valsalva maneuver is used to evaluate for parasympathetic dysfunction through the Valsalva ratio. In addition, sympathetic adrenergic function is assessed through evaluation of blood pressure response during the Valsalva maneuver. Abnormalities to the Valsalva maneuver can suggest clues towards an autonomic cause of syncope. Head-up tilt table testing is an important part of the autonomic evaluation of patients with syncope, and can be diagnostic for many disorders that result in syncope including orthostatic hypotension, neurally mediated syncope, postural tachycardia syndrome or delayed orthostatic hypotension. Autonomic function testing provides a safe and controlled environment for evaluation of patients, and plays a pivotal role in the diagnosis of syncope, particularly in challenging cases. While the initial clinical evaluation of syncope involves a detailed history and physical examination; in situations where the diagnosis is unknown, the addition of autonomic testing is complementary and can lead to identification of autonomic causes of syncope. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Cardiac autonomic dysfunction in West syndrome.

    Science.gov (United States)

    Jansen, Katrien; Vandeput, Steven; Van Huffel, Sabine; Lagae, Lieven

    2012-12-01

    West syndrome is an age-dependent epileptic encephalopathy. Autonomic changes are increasingly being recognized in patients with epilepsy: cardiac autonomic function is mediated by sympathetic and parasympathetic efferent activity to the heart and can provide information on the functional state of the autonomic nervous system. The goal of the study is to evaluate the effect of an early epileptic encephalopathy on the autonomic nervous system by measuring heart rate variability. Cardiac autonomic function was evaluated in 13 patients with West syndrome by measuring heart rate variability during 5 min epochs of ECG in wake, stage 2 and slow wave sleep. In 5 patients who developed subsequently another type of epilepsy, a second evaluation was performed after 3 years of follow-up. Results showed a lower heart rate in stage 2 sleep in patients with West syndrome. Spectral components did not show significant differences compared to age matched controls at the moment of presentation. After follow-up of 3 years we were able to demonstrate higher low frequency (LF), lower high frequency (HF) and a higher LF/HF ratio during slow wave sleep. This study shows a lower heart rate in patients presenting with West syndrome, already at the onset of the syndrome and before ACTH treatment. The epileptic encephalopathy is not sufficient to alter spectral components of heart rate at the moment of presentation. However, already after 3 years of epilepsy, chronic autonomic changes appear. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. The Wilms tumor gene, Wt1, is critical for mouse spermatogenesis via regulation of sertoli cell polarity and is associated with non-obstructive azoospermia in humans.

    Directory of Open Access Journals (Sweden)

    Xiao Na Wang

    Full Text Available Azoospermia is one of the major reproductive disorders which cause male infertility in humans; however, the etiology of this disease is largely unknown. In the present study, six missense mutations of WT1 gene were detected in 529 human patients with non-obstructive azoospermia (NOA, indicating a strong association between WT1 mutation and NOA. The Wilms tumor gene, Wt1, is specifically expressed in Sertoli cells (SCs which support spermatogenesis. To examine the functions of this gene in spermatogenesis, Wt1 was deleted in adult testis using Wt1(flox and Cre-ER(TM mice strains. We found that inactivation of Wt1 resulted in massive germ cell death and only SCs were present in most of the seminiferous tubules which was very similar to NOA in humans. In investigating the potential mechanism for this, histological studies revealed that the blood-testis barrier (BTB was disrupted in Wt1 deficient testes. In vitro studies demonstrated that Wt1 was essential for cell polarity maintenance in SCs. Further studies found that the expression of cell polarity associated genes (Par6b and E-cadherin and Wnt signaling genes (Wnt4, Wnt11 were downregulated in Wt1 deficient SCs, and that the expression of Par6b and E-cadherin was regulated by Wnt4. Our findings suggest that Wt1 is important in spermatogenesis by regulating the polarity of SCs via Wnt signaling pathway and that WT1 mutation is one of the genetic causes of NOA in humans.

  20. Dioxin-induced changes in epididymal sperm count and spermatogenesis Mudanças induzidas por dioxina na contagem epididimal de esperma e espermatogênese

    Directory of Open Access Journals (Sweden)

    Warren G. Foster

    2011-06-01

    Full Text Available A single in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD on gestation day 15 decreased epididymal sperm count in adult rats and thus was used to establish a tolerable daily intake for TCDD. However, several laboratories have been unable to replicate these findings. Moreover, conflicting reports of TCDD effects on daily sperm production suggest that spermatogenesis may not be as sensitive to the adverse effects of TCDD as previously thought. We performed a PubMed search using relevant search terms linking dioxin exposure with adverse effects on reproduction and spermatogenesis. Developmental exposure to TCDD is consistently linked with decreased cauda epididymal sperm counts in animal studies, although at higher dose levels than those used in some earlier studies. However, the evidence linking in utero TCDD exposure and spermatogenesis is not convincing. Animal studies provide clear evidence of an adverse effect of in utero TCDD exposure on epididymal sperm count but do not support the conclusion that spermatogenesis is adversely affected. The mechanisms underlying decreased epididymal sperm count are unknown; however, we postulate that epididymal function is the key target for the adverse effects of TCDD.Uma única exposição in utero a 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD no 15º dia de gestação diminuiu a contagem de esperma epididimal em ratos adultos e por isso foi utilizada para estabelecer uma dosagem diária tolerável para TCDD. No entanto, diversos laboratórios não conseguiram reproduzir esses resultados. Além disso, relatórios conflitantes dos efeitos de TCDD na produção diária de esperma sugere que espermatogênese pode não ser tão sensível aos efeitos adversos do TCDD como antes se pensava. Foi feita uma pesquisa no PubMed usando termos de pesquisa relevantes, relacionados à exposição à dioxina com efeitos adversos na reprodução e na espermatogênese. Exposição em desenvolvimento ao TCDD

  1. Investigation of Opioid Growth Factor Pathway Inhibition on the Histologic Structure of Testicular Tissue and Microscopic Indices of Spermatogenesis in Adult Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Razi Davoud Khar

    2017-03-01

    Full Text Available Background and aims: Endogenous opioids function as negative factors affecting the growth has been established. The most influential factor in the growth and differentiation of the proliferating cells is the opioid growth factor (OGF. Recently, some studies have been completed about the effects of opioid growth factor in the pathogenesis of diabetes and the beneficial effects of inhibition of this growth pathway have been demonstrated. The aim of this study was to investigate the effect of inhibition of opioids growth pathway, in proliferation and growth of testicular germ cells and spermatogenesis following experimental diabetes in adult mice.

  2. Building sustainability

    CSIR Research Space (South Africa)

    Mass Media

    2007-11-01

    Full Text Available , sustainable design is not compulsory at university so we still have a long way to go”. Van Wyk is certainly knowledge- able on this subject. He graduated as an architect in 1980 and practised in the field for many years. He also served as a member... at universities, it will take several years before the first students graduate and even longer before they become experienced. This vacuum can only be overcome when government takes the lead.” Nevertheless Van Wyk realises this is too much to expect from...

  3. Autonomous Vehicles: Disengagements, Accidents and Reaction Times.

    Science.gov (United States)

    Dixit, Vinayak V; Chand, Sai; Nair, Divya J

    2016-01-01

    Autonomous vehicles are being viewed with scepticism in their ability to improve safety and the driving experience. A critical issue with automated driving at this stage of its development is that it is not yet reliable and safe. When automated driving fails, or is limited, the autonomous mode disengages and the drivers are expected to resume manual driving. For this transition to occur safely, it is imperative that drivers react in an appropriate and timely manner. Recent data released from the California trials provide compelling insights into the current factors influencing disengagements of autonomous mode. Here we show that the number of accidents observed has a significantly high correlation with the autonomous miles travelled. The reaction times to take control of the vehicle in the event of a disengagement was found to have a stable distribution across different companies at 0.83 seconds on average. However, there were differences observed in reaction times based on the type of disengagements, type of roadway and autonomous miles travelled. Lack of trust caused by the exposure to automated disengagements was found to increase the likelihood to take control of the vehicle manually. Further, with increased vehicle miles travelled the reaction times were found to increase, which suggests an increased level of trust with more vehicle miles travelled. We believe that this research would provide insurers, planners, traffic management officials and engineers fundamental insights into trust and reaction times that would help them design and engineer their systems.

  4. Autonomous Vehicles: Disengagements, Accidents and Reaction Times.

    Directory of Open Access Journals (Sweden)

    Vinayak V Dixit

    Full Text Available Autonomous vehicles are being viewed with scepticism in their ability to improve safety and the driving experience. A critical issue with automated driving at this stage of its development is that it is not yet reliable and safe. When automated driving fails, or is limited, the autonomous mode disengages and the drivers are expected to resume manual driving. For this transition to occur safely, it is imperative that drivers react in an appropriate and timely manner. Recent data released from the California trials provide compelling insights into the current factors influencing disengagements of autonomous mode. Here we show that the number of accidents observed has a significantly high correlation with the autonomous miles travelled. The reaction times to take control of the vehicle in the event of a disengagement was found to have a stable distribution across different companies at 0.83 seconds on average. However, there were differences observed in reaction times based on the type of disengagements, type of roadway and autonomous miles travelled. Lack of trust caused by the exposure to automated disengagements was found to increase the likelihood to take control of the vehicle manually. Further, with increased vehicle miles travelled the reaction times were found to increase, which suggests an increased level of trust with more vehicle miles travelled. We believe that this research would provide insurers, planners, traffic management officials and engineers fundamental insights into trust and reaction times that would help them design and engineer their systems.

  5. Enabling technologies for autonomous MAV operations

    Science.gov (United States)

    Elbanhawi, M.; Mohamed, A.; Clothier, R.; Palmer, J. L.; Simic, M.; Watkins, S.

    2017-05-01

    The utility of micro air vehicles (MAVs) has expanded significantly in the last decade, and there are now numerous commercial systems available at relatively low cost. This expansion has arisen mainly due to the miniaturisation of flight control systems and advances in energy storage and propulsion technologies. Several emerging applications involve routine operation of MAVs in complex urban environments such as parcel delivery, communications relay and environmental monitoring. However, MAVs currently rely on one or more operators-in-the-loop and, whilst desirable, full autonomous operation has not yet been achieved. In this review paper, autonomous MAV operation in complex environments is explored with conceptualisation for future MAV operation in urban environments. Limitations of current technologies are systematically examined through consideration of the state-of-the-art and future trends. The main limitations challenging the realisation of fully autonomous MAVs are mainly attributed to: computational power, communication and energy storage. These limitations lead to poor sensing and planning capabilities, which are essential components of autonomous MAVs. Possible solutions are explored with goal of enabling MAVs to reliably operate autonomously in urban environments.

  6. Sustainable consumption and marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2016-01-01

    Sustainable development in global food markets is hindered by the discrepancy between positive consumer attitudes towards sustainable development or sustainability and the lack of corresponding sustainable consumption by a majority of consumers. Apparently for many (light user) consumers the

  7. Comprehensive analysis of tobacco pollen transcriptome unveils common pathways in polar cell expansion and underlying heterochronic shift during spermatogenesis

    Directory of Open Access Journals (Sweden)

    Hafidh Said

    2012-02-01

    certain genes in pollen-tube tip growth. In addition, we highlighted the molecular dynamics of core cell-cycle regulators in the male gametophyte and postulated the first genetic model to account for the differential timing of spermatogenesis among angiosperms and its coordination with female gametogenesis.

  8. Comprehensive analysis of tobacco pollen transcriptome unveils common pathways in polar cell expansion and underlying heterochronic shift during spermatogenesis

    Science.gov (United States)

    2012-01-01

    -tube tip growth. In addition, we highlighted the molecular dynamics of core cell-cycle regulators in the male gametophyte and postulated the first genetic model to account for the differential timing of spermatogenesis among angiosperms and its coordination with female gametogenesis. PMID:22340370

  9. EFEK ZAT AKTIF EKSTRAK DAUN JAMBU BIJI MERAH (PSIDIUM GUAJAVA.L TERHADAP SPERMATOGENESIS PADA TIKUS PUTIH JANTAN (RATTUS NORVEGICUS

    Directory of Open Access Journals (Sweden)

    Ervi Husni

    2016-11-01

    Full Text Available Pendahuluan: Jumlah penduduk Indonesia sensus tahun 2010 sebanyak 237,6 juta jiwa dengan laju pertumbuhan penduduk 1,49 % per tahun. Target RPJPMN 2010-2014 sebesar1,14 %, laju pertumbuhan penduduk saat ini  0,53 % masih lebih tinggi. Pengendalian penduduk diperlukan antara lain dengan pemakaian kontrasepsi pada wanita maupun pria. Keterlibatan pria dalam KB masih rendah hanya 6,26 %. Tujuan penelitian untuk membuktikan zat aktif daun jambu biji merah dapat menurunkan kadar FSH dan spermatogenesis pada tikus putih jantan (Rattus norvegikus. Metode: Penelitian ini merupakan penelitian eksperimen dengan rancangan Post test only control group design. Besar sampel menggunakan rumus Federer dengan jumlah sampel 30 ekor tikus putih, terbagi tiga kelompok yaitu Kelompok 1 (K1 kelompok kontrol diberikan larutan CMC 0,5 % 1 ml/ hari, Kelompok Perlakuan 1 (P1 diberikan ekstrak daun jambu biji merah dosis 40 mg/ml/hari dan kelompok Perlakuan 2 (P2 diberikan ekstrak daun jambu biji merah dosis 80 mg/ml/hari dan diberikan selama 30 hari. Variabel penelitian  jumlah sel spermatogenik ( Spermatogonium, Spermatosit primer dan Spermatid. Data dianalisis menggunakan uji  ANOVA. Hasil: Hasil analisis data dengan uji ANOVA jumlah sel spermatogonium nilai p 0,801 (p < 0,05: tidak ada perbedaan signifikan diantara ketiga kelompok, uji LSD tidak dilakukan. Hasil uji ANOVA untuk jumlah sel spermatosit primer didapatkan nilai p 0,102 ( p < 0,05 , berarti  tidak ada perbedaan signifikan diantara ketiga kelompok, uji LSD tidak dilakukan. Hasil uji ANOVA untuk jumlah sel spermatid nilai p 0,001  (p < 0,05 berarti terdapat perbedaan signifikan diantara ketiga kelompok. Hasil uji LSD kontrol dengan P1 (p 0,036 : berbeda, Kontrol dengan P2 (p <0,000: berbeda, P1 dengan P2 (p <0,033 : berbeda. Diskusi: Kesimpulan penelitian ini adalah pemberian ekstrak daun jambu biji merah tidak menurunkan jumlah sel spermatogonium dan sel spermatosit primer tetapi menurunkan jumlah

  10. Cardiovascular autonomic function tests in type 2 diabetes mellitus with micro albuminuria

    Directory of Open Access Journals (Sweden)

    Sudhavana S.

    2012-06-01

    Full Text Available Introduction: Cardiovascular disease is the leading cause of death in type2 diabetes (DM. Microalbuminuria (MAis strongly associated with cardiovascular complications in type2 diabetes. Impaired cardiovascular autonomicfunction and increased albumin excretion are related in patients with diabetes. So this study is designed toinvestigate the relationship between cardiovascular autonomic function and microalbuminuria in type2 diabetes.Methods: The study comprised of 180 subjects of age group>50 years, classified into 3 groups of 60 subjects each.DM without MA, DM with MA and controls. The tests performed were 1 Heart rate response to deep breathing,valsalva maneuver and standing; 2 Blood pressure response to standing and to sustained handgrip. Individual testswere given score of 0, 1, or 2 and an overall autonomic test score of 0-10 was obtained.Results: Mean autonomic score in control, DM without MA and DM with MA are 1.97 ± 0.81, 5.73 ± 1.26 and 7.00± 1.80 respectively. The Coefficient of variation (% of control, DM without MA, DM with MA is 41.1, 21.9 and25.7 respectively. A significant difference in autonomic score was observed in the DM without MA (P<0.01 andDM with MA (P<0.01 when compared to controls.Conclusion: In conclusion type2 diabetic individuals should be diagnosed early to prevent disease progression tomicroalbuminuria and thus minimize complications.

  11. Loss-of-function analysis reveals distinct requirements of the translation initiation factors eIF4E, eIF4E-3, eIF4G and eIF4G2 in Drosophila spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Sanjay Ghosh

    Full Text Available In eukaryotes, post-transcriptional regulation of gene expression has a key role in many cellular and developmental processes. Spermatogenesis involves a complex developmental program that includes changes in cell cycle dynamics and dramatic cellular remodeling. Translational control is critical for spermatogenesis in Drosophila as many mRNAs synthesized in the spermatocytes are translated only much later during spermatid differentiation. Testes-specific translation initiation factors eIF4E-3 and eIF4G2 are essential specifically for male fertility. However, details of their roles during different stages of spermatogenesis are unknown, and the role of canonical translation initiation factors in spermatogenesis remains unexplored. In this study, we addressed the functional role of eIF4E-1, eIF4E-3, eIF4G and eIF4G2 in testes development and formation of mature sperm. Using the UAS-Gal4 system and RNA interference, we systematically knocked down these four genes in different stages of germ cell development, and in the somatic cells. Our results show that eIF4E-1 function in early germ cells and the surrounding somatic cells is critical for spermatogenesis. Both eIF4E-1 and eIF4E-3 are required in spermatocytes for chromosome condensation and cytokinesis during the meiotic stages. Interestingly, we find that eIF4G knockdown did not affect male fertility while eIF4G2 has distinct functions during spermatogenesis; it is required in early germ cells for proper meiotic divisions and spermatid elongation while its abrogation in spermatocytes caused meiotic arrest. Double knockdown of eIF4G and eIF4G2 shows that these proteins act redundantly during the early stages of spermatogenesis. Taken together, our analysis reveals spatio-temporal roles of the canonical and testes-specific translation initiation factors in coordinating developmental programs during spermatogenesis.

  12. Lessons learned from the Autonomous Power System

    Science.gov (United States)

    Ringer, Mark J.; Quinn, Todd M.; Merolla, Anthony

    1992-01-01

    The Autonomous Power System (APS) project at the NASA Lewis Research Center is designed to demonstrate the applications of integrated intelligent diagnosis, control and scheduling techniques to space power distribution systems. The project consists of three elements: the Autonomous Power Expert System (APEX) for Fault Diagnosis, Isolation, and Recovery (FDIR); the Autonomous Intelligent Power Scheduler (AIPS) to efficiently assign activities start times and resources; and power hardware (Brassboard) to emulate a space-based power system. The APS project had been through one design iteration. Each of the three elements of the APS project has been designed, tested, and integrated into a complete working system. After these three portions were completed, an evaluation period was initiated. Each piece of the system was critiqued based on individual performance as well as the ability to interact with the other portions of the APS project. These critiques were then used to determine guidelines for new and improved components of the APS system.

  13. An Expert System for Autonomous Spacecraft Control

    Science.gov (United States)

    Sherwood, Rob; Chien, Steve; Tran, Daniel; Cichy, Benjamin; Castano, Rebecca; Davies, Ashley; Rabideau, Gregg

    2005-01-01

    The Autonomous Sciencecraft Experiment (ASE), part of the New Millennium Space Technology 6 Project, is flying onboard the Earth Orbiter 1 (EO-1) mission. The ASE software enables EO-1 to autonomously detect and respond to science events such as: volcanic activity, flooding, and water freeze/thaw. ASE uses classification algorithms to analyze imagery onboard to detect chang-e and science events. Detection of these events is then used to trigger follow-up imagery. Onboard mission planning software then develops a response plan that accounts for target visibility and operations constraints. This plan is then executed using a task execution system that can deal with run-time anomalies. In this paper we describe the autonomy flight software and how it enables a new paradigm of autonomous science and mission operations. We will also describe the current experiment status and future plans.

  14. Autonomous Robot Navigation based on Visual Landmarks

    DEFF Research Database (Denmark)

    Livatino, Salvatore

    2005-01-01

    The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully...... autonomous navigation and self-localization using automatically selected landmarks. The thesis investigates autonomous robot navigation and proposes a new method which benefits from the potential of the visual sensor to provide accuracy and reliability to the navigation process while relying on naturally...... update of the estimated robot position while the robot is moving. In order to make the system autonomous, both acquisition and observation of landmarks have to be carried out automatically. The thesis consequently proposes a method for learning and navigation of a working environment and it explores...

  15. On-Orbit Autonomous Assembly from Nanosatellites

    Science.gov (United States)

    Murchison, Luke S.; Martinez, Andres; Petro, Andrew

    2015-01-01

    The On-Orbit Autonomous Assembly from Nanosatellites (OAAN) project will demonstrate autonomous control algorithms for rendezvous and docking maneuvers; low-power reconfigurable magnetic docking technology; and compact, lightweight and inexpensive precision relative navigation using carrier-phase differential (CD) GPS with a three-degree of freedom ground demonstration. CDGPS is a specific relative position determination method that measures the phase of the GPS carrier wave to yield relative position data accurate to.4 inch (1 centimeter). CDGPS is a technology commonly found in the surveying industry. The development and demonstration of these technologies will fill a current gap in the availability of proven autonomous rendezvous and docking systems for small satellites.

  16. Autonomous driving technical, legal and social aspects

    CERN Document Server

    Gerdes, J; Lenz, Barbara; Winner, Hermann

    2016-01-01

    This book takes a look at fully automated, autonomous vehicles and discusses many open questions: How can autonomous vehicles be integrated into the current transportation system with diverse users and human drivers? Where do automated vehicles fall under current legal frameworks? What risks are associated with automation and how will society respond to these risks? How will the marketplace react to automated vehicles and what changes may be necessary for companies? Experts from Germany and the United States define key societal, engineering, and mobility issues related to the automation of vehicles. They discuss the decisions programmers of automated vehicles must make to enable vehicles to perceive their environment, interact with other road users, and choose actions that may have ethical consequences. The authors further identify expectations and concerns that will form the basis for individual and societal acceptance of autonomous driving. While the safety benefits of such vehicles are tremendous, the auth...

  17. Development of an autonomous power system testbed

    International Nuclear Information System (INIS)

    Barton, J.R.; Adams, T.; Liffring, M.E.

    1985-01-01

    A power system testbed has been assembled to advance the development of large autonomous electrical power systems required for the space station, spacecraft, and aircraft. The power system for this effort was designed to simulate single- or dual-bus autonomous power systems, or autonomous systems that reconfigure from a single bus to a dual bus following a severe fault. The approach taken was to provide a flexible power system design with two computer systems for control and management. One computer operates as the control system and performs basic control functions, data and command processing, charge control, and provides status to the second computer. The second computer contains expert system software for mission planning, load management, fault identification and recovery, and sends load and configuration commands to the control system

  18. Control of autonomous robot using neural networks

    Science.gov (United States)

    Barton, Adam; Volna, Eva

    2017-07-01

    The aim of the article is to design a method of control of an autonomous robot using artificial neural networks. The introductory part describes control issues from the perspective of autonomous robot navigation and the current mobile robots controlled by neural networks. The core of the article is the design of the controlling neural network, and generation and filtration of the training set using ART1 (Adaptive Resonance Theory). The outcome of the practical part is an assembled Lego Mindstorms EV3 robot solving the problem of avoiding obstacles in space. To verify models of an autonomous robot behavior, a set of experiments was created as well as evaluation criteria. The speed of each motor was adjusted by the controlling neural network with respect to the situation in which the robot was found.

  19. Autonomous calibration of single spin qubit operations

    Science.gov (United States)

    Frank, Florian; Unden, Thomas; Zoller, Jonathan; Said, Ressa S.; Calarco, Tommaso; Montangero, Simone; Naydenov, Boris; Jelezko, Fedor

    2017-12-01

    Fully autonomous precise control of qubits is crucial for quantum information processing, quantum communication, and quantum sensing applications. It requires minimal human intervention on the ability to model, to predict, and to anticipate the quantum dynamics, as well as to precisely control and calibrate single qubit operations. Here, we demonstrate single qubit autonomous calibrations via closed-loop optimisations of electron spin quantum operations in diamond. The operations are examined by quantum state and process tomographic measurements at room temperature, and their performances against systematic errors are iteratively rectified by an optimal pulse engineering algorithm. We achieve an autonomous calibrated fidelity up to 1.00 on a time scale of minutes for a spin population inversion and up to 0.98 on a time scale of hours for a single qubit π/2 -rotation within the experimental error of 2%. These results manifest a full potential for versatile quantum technologies.

  20. Irresponsibilities, inequalities and injustice for autonomous vehicles

    DEFF Research Database (Denmark)

    Liu, Hin-Yan

    2017-01-01

    With their prospect for causing both novel and known forms of damage, harm and injury, the issue of responsibility has been a recurring theme in the debate concerning autonomous vehicles. Yet, the discussion of responsibility has obscured the finer details both between the underlying concepts...... of responsibility, and their application to the interaction between human beings and artificial decision-making entities. By developing meaningful distinctions and examining their ramifications, this article contributes to this debate by refining the underlying concepts that together inform the idea...... of responsibility. Two different approaches are offered to the question of responsibility and autonomous vehicles: targeting and risk distribution. The article then introduces a thought experiment which situates autonomous vehicles within the context of crash optimisation impulses and coordinated or networked...

  1. Blood pressure regulation in diabetic autonomic neuropathy

    DEFF Research Database (Denmark)

    Hilsted, J

    1985-01-01

    Defective blood pressure responses to standing, exercise and epinephrine infusions have been demonstrated in diabetic patients with autonomic neuropathy. The circulatory mechanisms underlying blood pressure responses to exercise and standing up in these patients are well characterized: In both...... which may contribute to exercise hypotension in these patients. During hypoglycemia, blood pressure regulation seems intact in patients with autonomic neuropathy. This is probably due to release of substantial amounts of catecholamines during these experiments. During epinephrine infusions a substantial...... blood pressure fall ensues in patients with autonomic neuropathy, probably due to excessive muscular vasodilation. It is unresolved why blood pressure regulation is intact during hypoglycemia and severely impaired--at similar catecholamine concentrations--during epinephrine infusions....

  2. Study of the Protective Effects of Quince (Cydonia Oblonga Leaf Extract on the Histologic Structure and Microscopic Indices of Spermatogenesis Following Induction of Diabetes in Adult Rats

    Directory of Open Access Journals (Sweden)

    Davoud Kianifard

    2016-11-01

    Full Text Available Various types of infertility are associated with uncontrolled hyperglycemia. Development of oxidative stress is one the most important factors in the alteration of spermatogenesis in diabetic conditions. Testicular tissue is one of the sensitive organs to environmental damages. Natural antioxidants are considered as preventive and therapeutic strategies in cases of diabetic side effects. Cydonia oblonga leaf extract contains natural antioxidant compounds. The flavonoid compounds of the quince have strong antioxidant and immune-regulatory effects. According to little data about the protective effects of cydonia oblonga leaf extract on the structural alterations of testicular tissue following induction of diabetes, in this study protective aspects of this extract on the diabetic reproductive alteration were evaluated. Cydonia oblonga leaf extract was gavaged in two doses of 250 and 500 mg/kg. The number of 56 adult rats were divided into seven groups consisted of control, extract treated control groups, diabetic, extract treated diabetic groups and metformin treated diabetic group. Eight weeks after induction of diabetes, the body and testicular weight were measured and microscopic and histomorphometric studies were done on tissue samples. In control groups, the administration of extract was not any effect on histomorphometric parameters. In extract treated diabetic groups, the mean of body weight, histologic parameters and spermatogenesis indices were improved in comparison to non-treated diabetic group. The results of this study showed that, natural antioxidant such as cydonia oblonga leaf extract in some degrees could be effective in reduction of hyperglycemic side effects on target organs.

  3. Anatomy and histology of the male reproductive tract and spermatogenesis fine structure in the lesser anteater (Tamandua tetradactyla, Myrmecophagidae, Xenarthra): morphological evidences of reproductive functions.

    Science.gov (United States)

    Rossi, L F; Luaces, J P; Aldana Marcos, H J; Cetica, P D; Perez Jimeno, G; Merani, M S

    2013-08-01

    The anatomy and histology of the male genital tract of the lesser anteater were studied. Fine details of spermatozoa regarding their genesis and morphology were also studied in six adult specimens. The testes lie in the pelvic cavity. The deferent duct emerges from the epididymis and opens into the ejaculatory duct, which drains into the membranous urethra. Accessory glands (prostate, seminal vesicle and bulbourethral gland) are histologically similar to those described in other mammals. The short penis presents an urethral orifice, while the corpus spongiosum becomes thinner at the end indicating the absence of a histologically defined glans. The seminiferous epithelium shows: (1) Sertoli cells with deep nuclear indentations, (2) spermatogonia with crusty-like chromatin, (3) spermatocytes at different stages of maturation and (4) three morphologically distinct stages of spermatid differentiation according to nuclear shape, acrosome development and chromatin condensation. Sperm heads appear oval. The length of the spermatozoa averages 67.33 ± 1.60 μm. Two specimens with inactive spermatogenesis were azoospermic. Their testes and epididymis presented sizes smaller than those with active spermatogenesis. These studies together with others in anteaters may contribute to successful breeding in conservation programmes. © 2012 Blackwell Verlag GmbH.

  4. Some aspects on the reproductive cycle of European conger eel, Conger conger (Linnaeus, 1758 (Osteichthyes, Anguilliformes, Congridae captured from Western Algerian coasts: a histological description of spermatogenesis

    Directory of Open Access Journals (Sweden)

    Abi-ayad Sidi-Mohammed El-Amine

    2011-09-01

    Full Text Available The aim of this work was to study the annual reproductive cycle of European conger eel (Conger conger,Linnaeus, 1758 through analysis and description of spermatogenesis. A sample of 168 males was capturedbetween September 2008 and August 2009 from the Western coast of Algeria, from Béni Saf. Fish length andweight varied between 26.20-112 cm and 0.45-3.44 kg, respectively.Condition factors (K, gonadosomatic index (G.S.I. and hepatosomatic index (H.S.I. were calculatedmonthly. Factor K reached the minimum in August/September (0.10% corresponding to reproductive periodand a maximum in January (0.18%. Although G.S.I. values revealed to be statistically not significant, therewere two peaks for G.S.I., the first in March, denoting the beginning of spermatogenesis, and the second inAugust/September, indicating the reproduction period. H.S.I. reached a peak in December (1.90%, then thevalue decreased to a minimum in April.Histological analysis of testis allowed us to distinguish 5 stages summarized as follows: Stage 1:Spermatogonia A; Stage 2: Spermatogonia B; Stage 3: Spermatocytes and spermatids; Stage 4: Spermatocytes,spermatids and spermatozoa (cytodifferentiation of spermatids into spermatozoa; Stage 5: Spermatozoa(spermiogenesis or cytodifferentiation of spermatids into spermatozoa.

  5. Evaluation of Fertility Disrupting Potentials of Abrus precatorius Seed Extracts in Male Rats for Arresting Spermatogenesis and Suppressed Fertility In Vivo

    Directory of Open Access Journals (Sweden)

    Saranika Talukder

    2014-01-01

    Full Text Available This study was aimed to evaluate the contraceptive potentials of different chemical extracts of Abrus precatorius seeds in male albino rats. The active ingredients of crushed seeds were extracted with 60% aqueous acetone and then partitioned consecutively with n-hexane, ethyl acetate, methanol and water. Water suspended chemical fractions at different doses were administered orally to the male rats for 40 days. Effects of different treatments on various male reproductive endpoints and contraceptive efficacy were evaluated. Oral administration of both organic (methanol soluble at 50 and 75 mg/kg BW and aqueous soluble of A. precatorius seed extracts caused infertility in study subjects at varying degrees. At necropsy, average weights of testes, epididymis, ventral prostate gland and seminal vesicles were decreased significantly. Histology of testes revealed marked atrophy of the seminiferous tubules characterized by disruption of the germinal epithelium and atrophy of the Leydig cells. Epididymis also showed histological alterations. Hormonal assay revealed a significant decrease in serum level of testosterone, follicle stimulating hormone (FSH and luteinizing hormone (LH that possibly resulted in suppressed spermatogenesis of male rats. These effects lead to the reduction of pregnancy rate of untreated fertile female rats while mated with the methanol extract (50 and 75 mg/kg BW and aqueous extract-treated male rats. The results show that A. precatorius seed extract causes suppression of spermatogenesis and fertility, thereby suggesting the potential of this plant in the regulation of male fertility.

  6. Evaluations of boar gonad development, spermatogenesis with regard to semen characteristics, libido and serum testosterone levels based on large White Duroc x Chinese Erhualian crossbred boars.

    Science.gov (United States)

    Ren, D; Xing, Y; Lin, M; Wu, Y; Li, K; Li, W; Yang, S; Guo, T; Ren, J; Ma, J; Lan, L; Huang, L

    2009-12-01

    Chinese Erhualian pigs are known for prolificacy with distinct reproductive traits compared with Western commercial breeds. In this study, a four-generation intercross resource population was constructed using White Duroc boars and Chinese Erhualian sows as founder animals, and a total of 14 male reproductive traits were recorded in 411 F2/F3 boars including the testis and epididymis weights, the seminiferous tubular diameter and spermatogenesis at 60, 90 and 300 days of age, semen characteristics, serum testosterone concentration and libido level at 300 days of age. The White Duroc-Erhualian boars showed remarkable segregations in the traits measured except for the seminiferous tubular diameter and had high ratio (13.9%) of the abnormality of spermatogenesis, providing a good experimental population for detecting quantitative trait loci affecting these male reproductive traits. Furthermore, the correlations among nine male reproductive traits at 300 days of age indicated that the testis weight and the body weight were strongly correlated with the sperm production, supporting the two traits as important parameters for boar selection to increase sperm production and ultimately improve boar fertility. The libido level in the White Duroc-Erhualian boars that was evaluated by a new and easily recorded scoring system showed a significant correlation with serum testosterone concentration. Yet, both libido and serum testosterone concentration were not correlated with the sperm production. Results of this study provided new information on the male reproductive physiology and genetics in Chinese Erhualian and White Duroc boars.

  7. The ubiquitin ligase Ubr2, a recognition E3 component of the N-end rule pathway, stabilizes Tex19.1 during spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Fang Yang

    2010-11-01

    Full Text Available Ubiquitin E3 ligases target their substrates for ubiquitination, leading to proteasome-mediated degradation or altered biochemical properties. The ubiquitin ligase Ubr2, a recognition E3 component of the N-end rule proteolytic pathway, recognizes proteins with N-terminal destabilizing residues and plays an important role in spermatogenesis. Tex19.1 (also known as Tex19 has been previously identified as a germ cell-specific protein in mouse testis. Here we report that Tex19.1 forms a stable protein complex with Ubr2 in mouse testes. The binding of Tex19.1 to Ubr2 is independent of the second position cysteine of Tex19.1, a putative target for arginylation by the N-end rule pathway R-transferase. The Tex19.1-null mouse mutant phenocopies the Ubr2-deficient mutant in three aspects: heterogeneity of spermatogenic defects, meiotic chromosomal asynapsis, and embryonic lethality preferentially affecting females. In Ubr2-deficient germ cells, Tex19.1 is transcribed, but Tex19.1 protein is absent. Our results suggest that the binding of Ubr2 to Tex19.1 metabolically stabilizes Tex19.1 during spermatogenesis, revealing a new function for Ubr2 outside the conventional N-end rule pathway.

  8. Effect of Hydro Alcoholic Ginger Extracts on the Body Weight, Testis Weight and Spermatogenesis in Male Rats Undergoing Chemotherapy with Cyclophosphamide

    Directory of Open Access Journals (Sweden)

    E Sharifi

    2010-03-01

    Full Text Available Introduction: Cyclophosphamide is used as an anti cancer medicine in chemotherapy. This is an alkalizing medicine and causes the binding of DNA strands, breaking of DNA and control of protein synthesis and RNA. The side effects of this medicine include lack of appetite, nausea, reduction in activity of sexual lymph nodes, causing amenorrhea, azoospermia and oligospermia. Ginger includes many compounds, some of which are shogaols, gingerols, pyrogallols and sesquiterpenes. Ginger has anti nauseating, anti cancer, anti oxidant effects and eliminates free radicals. This medicine is used along with cyclophosphamide to reduce its destructive side effects in the body. Methods: For 21 days, the rats were fed with ginger and cyclophosphamide. After 21 days, the animals were weighed and rendered unconscious. Their testes were removed and tissue samples were provided from their testes. Results: The results showed that cyclophosphamide alone reduces body weight, testes weight and spermatogenesis as compared to the control group. In other experimental groups that were fed with ginger and cyclophosphamide, increased dosage of ginger increased the body weight, the testes weight and spermatogenesis in comparison to the other experimental groups. Conclusion: It seems that compounds present in ginger are anti tumoral and control the production of active metabolites. Therefore, if administered together with Cyclophosphamide, it can be useful and effective in patients undergoing chemotherapy.

  9. Enhanced role of elaidic acid on acrylamide-induced oxidative stress in epididymis and epididymal sperm that contributed to the impairment of spermatogenesis in mice.

    Science.gov (United States)

    Zhang, Jian-xin; Yue, W B; Ren, Y S; Zhang, C X

    2010-09-01

    Acrylamide (ACR) and trans fatty acids (TFA) could be found co-existent in many foods processed by high temperature. Our study investigated effect of elaidic acid (ELA), the predominant TFA, on deficits of spermatogenesis induced by ACR. Results showed that ELA enhanced the decreases of spermatogonia along with mature sperms after treatment of ACR, and that spermatozoa quality was significantly reduced by addition of ELA to mice treated with ACR. Moreover, ELA play an enhancing role in ACR-induced up-regulating of malondialdehyde (MDA) level in epididymal sperm and cauda epididymides, also up-regulating of protein carbonyls (PCOs) level in cauda epididymides. Meanwhile, ELA play an enhancing role in ACR-induced reducing of activity of superoxide dismutases (SOD) in epididymal sperm, corpus and cauda epididymides, also the reducing of activity of glutathione peroxidase (GPx) in cauda epididymides. These data suggest that ELA enhances ACR-induced oxidative stress in the epididymis and epididymal sperm of mice and has subsequent effect on spermatogenesis in mice testis.

  10. Interdependences between sustainable development and sustainable economy

    OpenAIRE

    Emilia Mioara CÂMPEANU; Carmen Valentina RĂDULESCU

    2014-01-01

    Sustainable development and sustainable economy are mostly used concepts. Understanding clearly their meaning allows their use in an appropriate context and, therefore, their boundaries in terms of theoretical and practical approaches on which occasion it can be given their interdependencies. The paper aim is to analyze the interdependences between sustainable development and sustainable economy.

  11. Are Turkish University Students Autonomous or Not?

    Directory of Open Access Journals (Sweden)

    Büşra Kırtık

    2017-01-01

    Full Text Available The present study tried to determine Turkish learners’ attitudes, and the Turkish education system’s approach towards learner autonomy with regard to three main points: 1 whether Turkish university students are aware of learner autonomy or not 2 whether Turkish university students have the characteristics of autonomous learners (whether they are autonomous learners or not, and 3 if the Turkish education system is suitable for fostering learner autonomy or not from the viewpoint of the participants. Participants were 50 second grade learners in the English Language Teaching Departments of Hacettepe University (N=10, Mehmet Akif Ersoy University (N=10, and Uludag University (N=30 who had already taken courses about learner autonomy.  The data were collected by means of a questionnaire which had two Likert-scale sections and an open-ended questions section. The first Likert-scale section contained 15 characteristics of autonomous learners each of which was rated by the participants in a scale from strongly disagree to agree, from 1 to 5. In the second Likert-scale section, the participants were asked to rate the Turkish education system’s five basic elements such as school curriculums, course materials, approaches used by the teachers in classrooms, learning activities, and classroom settings. Additionally, learners’ opinions about their awareness and understanding of learner autonomy were gathered by five open ended questions. The results proposed that the participants were aware of learner autonomy, and had the characteristics of autonomous learners. On the other hand, results showed that the Turkish education system was not suitable for autonomous learners and did not foster learner autonomy. The findings suggested that the Turkish education system should be designed again in such a way to support the autonomous learners and to foster learner autonomy in all sections of the education.

  12. Testicular heat exposure enhances the suppression of spermatogenesis by testosterone in rats: the "two-hit" approach to male contraceptive development.

    Science.gov (United States)

    Lue, Y; Hikim, A P; Wang, C; Im, M; Leung, A; Swerdloff, R S

    2000-04-01

    The objectives of the study were to determine stage-specific changes in the kinetics of germ cell apoptosis induced by administration of exogenous testosterone (T) alone and to examine whether addition of a single testicular heat exposure would enhance the induction of germ cell apoptosis and the suppression of spermatogenesis by T. Adult male rats were implanted with 3-cm SILASTIC brand capsules (Dow Corning Corp.) containing T for up to 6 weeks. Intratesticular T levels declined to 2.9% of control values by 1 week and remained suppressed at 2, 3, and 6 weeks after T administration. The incidence of germ cell apoptosis (expressed as numbers per 100 Sertoli cells) was low in control rats (0-9.52). After T treatment, the mean incidence of apoptosis at stages VII-VIII increased significantly by 1 week (21.43 +/-3.33) and showed further increases by 6 weeks (56.30 +/- 7.47); apoptotic rates remained low at early (I-VI) and later (XII-XIV) stages. To test whether the combination of T with a single testicular heat exposure resulted in more complete suppression of spermatogenesis than either treatment alone, four groups of adult rats received one of the following treatments: 1) a subdermal empty polydimethylsilozane implant, 2) exposure to a single testicular heating (43 C for 15 min) applied on day 14, 3) 3-cm T implant, or 4) 3-cm T implant and a single testicular heat exposure (applied on day 14). All animals were killed at the end of 6 weeks. In the heat-treated group, testis weight and testicular sperm counts were decreased to 65.4% and 28.9% of control levels, respectively. The corresponding values in the T-treated group were 49.7% and 24.9% of control levels, respectively. Notably, addition of heat to T further reduced testis weight to 31.1% of control levels and testicular sperm counts to near zero. Histomorphometric analysis showed that all treatments reduced seminiferous tubular diameter and epithelial and luminal volume, with the greatest decrease after

  13. Autonomous execution of the Precision Immobilization Technique

    Science.gov (United States)

    Mascareñas, David D. L.; Stull, Christopher J.; Farrar, Charles R.

    2017-03-01

    Over the course of the last decade great advances have been made in autonomously driving cars. The technology has advanced to the point that driverless car technology is currently being tested on publicly accessed roadways. The introduction of these technologies onto publicly accessed roadways not only raises questions of safety, but also security. Autonomously driving cars are inherently cyber-physical systems and as such will have novel security vulnerabilities that couple both the cyber aspects of the vehicle including the on-board computing and any network data it makes use of, with the physical nature of the vehicle including its sensors, actuators, and the vehicle chassis. Widespread implementation of driverless car technology will require that both the cyber, as well as physical security concerns surrounding these vehicles are addressed. In this work, we specifically developed a control policy to autonomously execute the Precision Immobilization Technique, a.k.a. the PIT maneuver. The PIT maneuver was originally developed by law enforcement to end high-speed vehicular pursuits in a quasi-safe manner. However, there is still a risk of damage/roll-over to both the vehicle executing the PIT maneuver as well as to the vehicle subject to the PIT maneuver. In law enforcement applications, it would be preferable to execute the PIT maneuver using an autonomous vehicle, thus removing the danger to law-enforcement officers. Furthermore, it is entirely possible that unscrupulous individuals could inject code into an autonomously-driving car to use the PIT maneuver to immobilize other vehicles while maintaining anonymity. For these reasons it is useful to know how the PIT maneuver can be implemented on an autonomous car. In this work a simple control policy based on velocity pursuit was developed to autonomously execute the PIT maneuver using only a vision and range measurements that are both commonly collected by contemporary driverless cars. The ability of this

  14. Design of an autonomous exterior security robot

    Science.gov (United States)

    Myers, Scott D.

    1994-01-01

    This paper discusses the requirements and preliminary design of robotic vehicle designed for performing autonomous exterior perimeter security patrols around warehouse areas, ammunition supply depots, and industrial parks for the U.S. Department of Defense. The preliminary design allows for the operation of up to eight vehicles in a six kilometer by six kilometer zone with autonomous navigation and obstacle avoidance. In addition to detection of crawling intruders at 100 meters, the system must perform real-time inventory checking and database comparisons using a microwave tags system.

  15. Emerging Technologies for Autonomous Language Learning

    Directory of Open Access Journals (Sweden)

    Mark Warschauer

    2011-09-01

    Full Text Available Drawing on a lengthier review completed for the US National Institute for Literacy, this paper examines emerging technologies that are applicable to self-access and autonomous learning in the areas of listening and speaking, collaborative writing, reading and language structure, and online interaction. Digital media reviewed include podcasts, blogs, wikis, online writing sites, text-scaffolding software, concordancers, multiuser virtual environments, multiplayer games, and chatbots. For each of these technologies, we summarize recent research and discuss possible uses for autonomous language learning.

  16. A mission planner for an autonomous tractor

    DEFF Research Database (Denmark)

    Bochtis, Dionysis; Vougioukas, S.G.; Griepentrog, Hans W.

    2009-01-01

    In this article, a mission planner of field coverage operations for an autonomous agricultural tractor is presented. Missions for a particular autonomous tractor are defined using an XML (extendible markup language) formatted file that can be uploaded to the tractor through the user interface...... and formulated, via semantic representations, as a vehicle routing problem (VRP). By using this approach, the total non-working distance can be reduced by up to 50% compared to the conventional non-optimized method. Three sets of experiments are presented. In the first set, three fields were separately covered...

  17. Advanced control architecture for autonomous vehicles

    Science.gov (United States)

    Maurer, Markus; Dickmanns, Ernst D.

    1997-06-01

    An advanced control architecture for autonomous vehicles is presented. The hierarchical architecture consists of four levels: a vehicle level, a control level, a rule-based level and a knowledge-based level. A special focus is on forms of internal representation, which have to be chosen adequately for each level. The control scheme is applied to VaMP, a Mercedes passenger car which autonomously performs missions on German freeways. VaMP perceives the environment with its sense of vision and conventional sensors. It controls its actuators for locomotion and attention focusing. Modules for perception, cognition and action are discussed.

  18. Autonomous control of distributed storages in microgrids

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Blaabjerg, Frede

    2011-01-01

    Operation of distributed generators in microgrids has widely been discussed, but would not be fully autonomous, if distributed storages are not considered. Storages in general are important, since they provide energy buffering to load changes, energy leveling to source variations and ride......-through enhancement to the overall microgrids. Recognizing their importance, this paper presents a scheme for sharing power among multiple distributed storages, in coordination with the distributed sources and loads. The scheme prompts the storages to autonomously sense for system conditions, requesting for maximum...

  19. Autonomous operation of distributed storages in microgrids

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Chai, Yi Kai; Li, Ding

    2014-01-01

    Operation of distributed generators in microgrids has been widely discussed, but would not be fully autonomous if distributed energy storages are not considered. Storages are important since they provide energy buffering to load changes, energy levelling to source variations and ride......-through enhancement to the microgrids. Recognising their importance, this study presents a scheme for sharing power among multiple distributed storages in coordination with the distributed sources and loads. The scheme prompts the storages to autonomously sense for local operating conditions, requesting for maximum...

  20. Applying Energy Autonomous Robots for Dike Inspection

    OpenAIRE

    Dresscher, Douwe; de Vries, Theodorus J.A.; Stramigioli, Stefano

    2015-01-01

    This article presents an exploratory study of an energy-autonomous robot that can be deployed on the Dutch dykes. Based on theory in energy harvesting from sun and wind and the energy-cost of locomotion an analytic expression to determine the feasible daily operational time of such a vehicle is composed. The parameters in this expression are identified using lab results and weather statistics. After an evaluation of the “Energy autonomous robot in the Netherlands‿ case, the results are genera...

  1. Sustaining observations in the polar oceans.

    Science.gov (United States)

    Abrahamsen, E P

    2014-09-28

    Polar oceans present a unique set of challenges to sustained observations. Sea ice cover restricts navigation for ships and autonomous measurement platforms alike, and icebergs present a hazard to instruments deployed in the upper ocean and in shelf seas. However, the important role of the poles in the global ocean circulation provides ample justification for sustained observations in these regions, both to monitor the rapid changes taking place, and to better understand climate processes in these traditionally poorly sampled areas. In the past, the vast majority of polar measurements took place in the summer. In recent years, novel techniques such as miniature CTD (conductivity-temperature-depth) tags carried by seals have provided an explosion in year-round measurements in areas largely inaccessible to ships, and, as ice avoidance is added to autonomous profiling floats and gliders, these promise to provide further enhancements to observing systems. In addition, remote sensing provides vital information about changes taking place in sea ice cover at both poles. To make these observations sustainable into the future, improved international coordination and collaboration is necessary to gain optimum utilization of observing networks. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  2. Sustainable Entrepreneurship

    DEFF Research Database (Denmark)

    Schaltegger, Stefan; Beckmann, Markus; Hockerts, Kai

    2018-01-01

    : a document analysis for developing a typology of ecopreneurs with user business models, and an in-depth case study analysis. We identify four patterns of entrepreneurial user business models in e-mobility: predominantly simple use, complementary business, feedback to core business, and additional business....... We also explore the transformation path of the case company, which starts with simple use and then moves to the feedback to core business pattern. By drawing on insights from lead user theory in innovation management and sustainable entrepreneurship, we ground the new concept in extant literature...... and develop propositions. These propositions uncover some properties of ecopreneurs, the diffusion of environmental technologies, and industry transformations due to user business models....

  3. Virtual Sustainability

    Directory of Open Access Journals (Sweden)

    William Sims Bainbridge

    2010-09-01

    Full Text Available In four ways, massively multiplayer online role-playing games may serve as tools for advancing sustainability goals, and as laboratories for developing alternatives to current social arrangements that have implications for the natural environment. First, by moving conspicuous consumption and other usually costly status competitions into virtual environments, these virtual worlds might reduce the need for physical resources. Second, they provide training that could prepare individuals to be teleworkers, and develop or demonstrate methods for using information technology to replace much transportation technology, notably in commuting. Third, virtual worlds and online games build international cooperation, even blending national cultures, thereby inching us toward not only the world consciousness needed for international agreements about the environment, but also toward non-spatial government that cuts across archaic nationalisms. Finally, realizing the potential social benefits of this new technology may urge us to reconsider a number of traditional societal institutions.

  4. Sustainability; Sustentabilidade

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-15

    This chapter analyses the production chain of ethanol, considering the impacts on the quality of the air, water supplies, soil occupation and biodiversity, and the efforts for the soil preservation. It is pointed out the activities of the production cycle and use of bio ethanol due to great uncertainties as far the environmental impacts is concerning and that will deserve more attention in future evaluations. At same time, the chapter highlights another activities where the present acknowledge is sufficient to assure the control and/or prediction of consequences of the desired intervention on the environment media to accommodate the sugar and ethanol production expansion. The consideration is not conservative but to promote the sustainable development.

  5. Chemosterilization: Spermatogenesis, Steroidogenesis ...

    African Journals Online (AJOL)

    the oxidative stress inducing (i.e., reactive oxygen species generating) ... of fertility is in direct relation to the degree of motility of sperm.[10] ... female. Furthermore, chemical castration had a greater effect on the decrease of aggression than surgical castration.[16]. In 2001, a study was performed to determine the effects.

  6. On-orbit Autonomous Assembly from Nanosatellites (OAAN)

    Data.gov (United States)

    National Aeronautics and Space Administration — On-orbit Autonomous Assembly from Nanosatellites (OAAN) demonstrates the technology to autonomously dock two or more nanosatellites to form an integrated satellite...

  7. Navigation of autonomous underwater vehicle using extended kalman filter

    Digital Repository Service at National Institute of Oceanography (India)

    Ranjan, T.N.; Nherakkol, A.; Navelkar, G.S.

    To navigate the Autonomous Underwater Vehicle (AUV) accurately is one of the most important aspects in its application. A truly autonomous vehicle must determine its position which requires the optimal integration of all available attitude...

  8. Autonomous Vehicle Survey of Bicyclists and Pedestrians in Pittsburgh, 2017

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — In Pittsburgh, Autonomous Vehicle (AV) companies have been testing autonomous vehicles since September 2016. However, the tech is new, and there have been some...

  9. CSIR eNews: Mobile Intelligent Autonomous Systems

    CSIR Research Space (South Africa)

    CSIR

    2008-03-01

    Full Text Available The CSIR plans to address the challenges associated with intelligent mobile autonomous mapping of dynamic and unstructured environments through focused scientific research in the domains of intelligent autonomous localisation and dynamic scene...

  10. GPM GROUND VALIDATION AUTONOMOUS PARSIVEL UNIT (APU) NSSTC V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Autonomous Parsivel Unit (APU) NSSTC dataset was collected by the Autonomous Parsivel Unit (APU), which is an optical disdrometer based on...

  11. GPM GROUND VALIDATION AUTONOMOUS PARSIVEL UNIT (APU) GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Autonomous Parsivel Unit (APU) GCPEx dataset was collected by the Autonomous Parsivel Unit (APU), which is an optical disdrometer that...

  12. GPM GROUND VALIDATION AUTONOMOUS PARSIVEL UNIT (APU) HYMEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Autonomous Parsivel Unit (APU) HyMeX dataset was collected by the Autonomous Parsivel Unit (APU), which is an optical disdrometer that...

  13. Conference proceedings of the Northeast Autonomous Vehicle Summit.

    Science.gov (United States)

    2017-05-24

    The development of autonomous vehicle technology and potential adoption of autonomous vehicles is occurring at a rapid rate in the United States. As this technology evolves, there are many technical, logistical and legal issues that need to be addres...

  14. NASA Ames Sustainability Initiatives: Aeronautics, Space Exploration, and Sustainable Futures

    Science.gov (United States)

    Grymes, Rosalind A.

    2015-01-01

    In support of the mission-specific challenges of aeronautics and space exploration, NASA Ames produces a wealth of research and technology advancements with significant relevance to larger issues of planetary sustainability. NASA research on NexGen airspace solutions and its development of autonomous and intelligent technologies will revolutionize both the nation's air transporation systems and have applicability to the low altitude flight economy and to both air and ground transporation, more generally. NASA's understanding of the Earth as a complex of integrated systems contributes to humanity's perception of the sustainability of our home planet. Research at NASA Ames on closed environment life support systems produces directly applicable lessons on energy, water, and resource management in ground-based infrastructure. Moreover, every NASA campus is a 'city'; including an urbanscape and a workplace including scientists, human relations specialists, plumbers, engineers, facility managers, construction trades, transportation managers, software developers, leaders, financial planners, technologists, electricians, students, accountants, and even lawyers. NASA is applying the lessons of our mission-related activities to our urbanscapes and infrastructure, and also anticipates a leadership role in developing future environments for living and working in space.

  15. An autonomous control framework for advanced reactors

    Directory of Open Access Journals (Sweden)

    Richard T. Wood

    2017-08-01

    Full Text Available Several Generation IV nuclear reactor concepts have goals for optimizing investment recovery through phased introduction of multiple units on a common site with shared facilities and/or reconfigurable energy conversion systems. Additionally, small modular reactors are suitable for remote deployment to support highly localized microgrids in isolated, underdeveloped regions. The long-term economic viability of these advanced reactor plants depends on significant reductions in plant operations and maintenance costs. To accomplish these goals, intelligent control and diagnostic capabilities are needed to provide nearly autonomous operations with anticipatory maintenance. A nearly autonomous control system should enable automatic operation of a nuclear power plant while adapting to equipment faults and other upsets. It needs to have many intelligent capabilities, such as diagnosis, simulation, analysis, planning, reconfigurability, self-validation, and decision. These capabilities have been the subject of research for many years, but an autonomous control system for nuclear power generation remains as-yet an unrealized goal. This article describes a functional framework for intelligent, autonomous control that can facilitate the integration of control, diagnostic, and decision-making capabilities to satisfy the operational and performance goals of power plants based on multimodular advanced reactors.

  16. An autonomous control framework for advanced reactors

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard T.; Upadhyaya, Belle R.; Floyd, Dan C. [Dept. of Nuclear Engineering, University of Tennessee, Knoxville (United States)

    2017-08-15

    Several Generation IV nuclear reactor concepts have goals for optimizing investment recovery through phased introduction of multiple units on a common site with shared facilities and/or reconfigurable energy conversion systems. Additionally, small modular reactors are suitable for remote deployment to support highly localized microgrids in isolated, underdeveloped regions. The long-term economic viability of these advanced reactor plants depends on significant reductions in plant operations and maintenance costs. To accomplish these goals, intelligent control and diagnostic capabilities are needed to provide nearly autonomous operations with anticipatory maintenance. A nearly autonomous control system should enable automatic operation of a nuclear power plant while adapting to equipment faults and other upsets. It needs to have many intelligent capabilities, such as diagnosis, simulation, analysis, planning, reconfigurability, self-validation, and decision. These capabilities have been the subject of research for many years, but an autonomous control system for nuclear power generation remains as-yet an unrealized goal. This article describes a functional framework for intelligent, autonomous control that can facilitate the integration of control, diagnostic, and decision-making capabilities to satisfy the operational and performance goals of power plants based on multimodular advanced reactors.

  17. Control algorithms for autonomous robot navigation

    International Nuclear Information System (INIS)

    Jorgensen, C.C.

    1985-01-01

    This paper examines control algorithm requirements for autonomous robot navigation outside laboratory environments. Three aspects of navigation are considered: navigation control in explored terrain, environment interactions with robot sensors, and navigation control in unanticipated situations. Major navigation methods are presented and relevance of traditional human learning theory is discussed. A new navigation technique linking graph theory and incidental learning is introduced

  18. Sleep restriction progress to cardiac autonomic imbalance ...

    African Journals Online (AJOL)

    Since it's more difficult to maintain adequate sleep duration among night watchmen during their working schedule, hence the purpose of our present study was to investigate whether mental stress or fatigue over restricted sleep period in night shift, affects HRV, in order to elucidate on cardiac autonomic modulation among ...

  19. Distributed formation control for autonomous robots

    NARCIS (Netherlands)

    Garcia de Marina Peinado, Hector Jesús

    2016-01-01

    This thesis addresses several theoretical and practical problems related to formation-control of autonomous robots. Formation-control aims to simultaneously accomplish the tasks of forming a desired shape by the robots and controlling their coordinated collective motion. This kind of robot

  20. The CASCADAS Framework for Autonomic Communications

    Science.gov (United States)

    Baresi, Luciano; Ferdinando, Antonio Di; Manzalini, Antonio; Zambonelli, Franco

    An interesting approach to the design and development of the future Internet foresees a networked service eco-system capable of seamlessly offering services for human-to-human, human-to-machine and machine-to-machine interactions. This chapter builds in this direction by describing a distributed component-ware framework for autonomic and situation-aware communication developed within the CASCADAS project. The core of this framework is the Autonomic Communication Element (ACE), an innovative software abstraction capable of providing dynamically adaptable services that can be built, composed, and let evolve according to autonomic principles. Services are capable of adapting their logic to the dynamically changing context they operate in without human intervention. As a result, whenever the need arises, ACEs can be federated autonomously and produce new services on a situation-aware basis. Systems and, in particular, eco-systems can thus be conceived as collections of ACEs. The chapter introduces the concept of ACE and its different facets. It also presents the architecture of a prototype ACE-based platform and exemplifies the different concepts through a future Pervasive Behavioral Advertisement scenario.

  1. Autonomous Control, Climate and Environmental Changes Effects ...

    African Journals Online (AJOL)

    Autonomous Control, Climate and Environmental Changes Effects on Trypanosomiasis in Sub-Saharan Africa: A Review. ... African trypanosomiasis is a parasitic disease that causes serious economic losses in livestock due to anemia, loss of condition and emaciation. The disease when neglected is lethal and untreated ...

  2. Autonomous Renewable Energy Systems | Van Voorden | Nigerian ...

    African Journals Online (AJOL)

    The problems of having many renewable sources such as wind and solar generating units in a power system are uncontrollable fluctuations in power generation and the difficulty in forecasting the power generation capability of these sources due to their stochastic nature. Therefore, autonomous electricity systems with a ...

  3. Autonomous biomorphic robots as platforms for sensors

    International Nuclear Information System (INIS)

    Tilden, M.; Hasslacher, B.; Mainieri, R.; Moses, J.

    1996-01-01

    The idea of building autonomous robots that can carry out complex and nonrepetitive tasks is an old one, so far unrealized in any meaningful hardware. Tilden has shown recently that there are simple, processor-free solutions to building autonomous mobile machines that continuously adapt to unknown and hostile environments, are designed primarily to survive, and are extremely resistant to damage. These devices use smart mechanics and simple (low component count) electronic neuron control structures having the functionality of biological organisms from simple invertebrates to sophisticated members of the insect and crab family. These devices are paradigms for the development of autonomous machines that can carry out directed goals. The machine then becomes a robust survivalist platform that can carry sensors or instruments. These autonomous roving machines, now in an early stage of development (several proof-of-concept prototype walkers have been built), can be developed so that they are inexpensive, robust, and versatile carriers for a variety of instrument packages. Applications are immediate and many, in areas as diverse as prosthetics, medicine, space, construction, nanoscience, defense, remote sensing, environmental cleanup, and biotechnology

  4. A universal projective synchronization of general autonomous ...

    Indian Academy of Sciences (India)

    This paper investigates the generalized projective synchronization in general autonomous chaotic system. A universal controller is designed and the effectiveness is verified via theoretical analysis and numerical simulations. The controller design is irrelevant to concrete system structure and initial values. It has strong ...

  5. A network of (autonomic) clock outputs

    NARCIS (Netherlands)

    Kalsbeek, A.; Perreau-Lenz, S.; Buijs, R. M.

    2006-01-01

    The circadian clock in the suprachiasmatic nuclei (SCN) is composed of thousands of oscillator neurons, each of which is dependent on the cell-autonomous action of a defined set of circadian clock genes. A major question is still how these individual oscillators are organized into a biological clock

  6. A network of (autonomic) clock outputs

    NARCIS (Netherlands)

    Kalsbeek, A.; Perreau-Lenz, S.; Buijs, R. M.

    2006-01-01

    The circadian clock in the suprachiasmatic nuclei (SCN) is composed of thousands of oscillator neurons, each dependent on the cell-autonomous action of a defined set of circadian clock genes. A major question is still how these individual oscillators are organized into a biological clock that

  7. Autonomic changes in fibromyalgia: Clinical and ...

    African Journals Online (AJOL)

    Background: Autonomic nervous system (ANS) dysfunction is one of the suggested pathophysiological mechanisms of fibromyalgia (FM). Its dysfunction may contribute to enhanced pain and other clinical problems associated with FM. Previous studies showed conflicting results regarding ANS function in FM. Some studies ...

  8. Information Engineering in Autonomous Robot Software

    NARCIS (Netherlands)

    Ziafati, P.

    2015-01-01

    In order to engage and help in our daily life, autonomous robots are to operate in dynamic and unstructured environments and interact with people. As the robot's environment and its behaviour are getting more complex, so are the robot's software and the knowledge that the robot needs to carry out

  9. Autonomous biomorphic robots as platforms for sensors

    Energy Technology Data Exchange (ETDEWEB)

    Tilden, M.; Hasslacher, B.; Mainieri, R.; Moses, J.

    1996-10-01

    The idea of building autonomous robots that can carry out complex and nonrepetitive tasks is an old one, so far unrealized in any meaningful hardware. Tilden has shown recently that there are simple, processor-free solutions to building autonomous mobile machines that continuously adapt to unknown and hostile environments, are designed primarily to survive, and are extremely resistant to damage. These devices use smart mechanics and simple (low component count) electronic neuron control structures having the functionality of biological organisms from simple invertebrates to sophisticated members of the insect and crab family. These devices are paradigms for the development of autonomous machines that can carry out directed goals. The machine then becomes a robust survivalist platform that can carry sensors or instruments. These autonomous roving machines, now in an early stage of development (several proof-of-concept prototype walkers have been built), can be developed so that they are inexpensive, robust, and versatile carriers for a variety of instrument packages. Applications are immediate and many, in areas as diverse as prosthetics, medicine, space, construction, nanoscience, defense, remote sensing, environmental cleanup, and biotechnology.

  10. Integrating the autonomous subsystems management process

    Science.gov (United States)

    Ashworth, Barry R.

    1992-01-01

    Ways in which the ranking of the Space Station Module Power Management and Distribution testbed may be achieved and an individual subsystem's internal priorities may be managed within the complete system are examined. The application of these results in the integration and performance leveling of the autonomously managed system is discussed.

  11. A universal projective synchronization of general autonomous ...

    Indian Academy of Sciences (India)

    Fuzhong Nian et al and the validity of our method was verified through theoretical analysis and numerical simulations. 2. Generalized projective synchronization controller design. Consider a general autonomous system: ˙X = AX + B. (1). Here X = [x1, x1,..., xn]T is the state vector of the drive system, B is a n × 1 constant.

  12. Autonomous Robot Navigation In Public Nature Park

    DEFF Research Database (Denmark)

    Andersen, Jens Christian; Andersen, Nils Axel; Ravn, Ole

    2005-01-01

    This extended abstract describes a project to make a robot travel autonomously across a public nature park. The challenge is to detect and follow the right path across junctions and open squares avoiding people and obstacles. The robot is equipped with a laser scanner, a (low accuracy) GPS, wheel...

  13. Control algorithms for autonomous robot navigation

    Energy Technology Data Exchange (ETDEWEB)

    Jorgensen, C.C.

    1985-09-20

    This paper examines control algorithm requirements for autonomous robot navigation outside laboratory environments. Three aspects of navigation are considered: navigation control in explored terrain, environment interactions with robot sensors, and navigation control in unanticipated situations. Major navigation methods are presented and relevance of traditional human learning theory is discussed. A new navigation technique linking graph theory and incidental learning is introduced.

  14. Monitoring aquatic environments with autonomous systems

    DEFF Research Database (Denmark)

    Christensen, Jesper Philip Aagaard

    High frequency measurements from autonomous sensors have become a widely used tool among aquatic scientists. This report focus primarily on the use of ecosystem metabolism based on high frequency oxygen measurements and relates the calculations to spatial variation, biomass of the primary produce...

  15. Autonomic dysfunction in a Jack Russell terrier

    Science.gov (United States)

    Caines, Deanne; Pinard, Chantale L.; Kruth, Stephen; Orr, Jeremy; James, Fiona

    2011-01-01

    A 4-year-old Jack Russell terrier was presented with an array of clinical signs suggestive of autonomic dysfunction. Many of the clinical signs were consistent with a diagnosis of dysautonomia; however, both chronicity and resolution of signs contradicted a diagnosis of this disease. PMID:21629424

  16. Autonomous droop scheme with reduced generation cost

    DEFF Research Database (Denmark)

    Nutkani, Inam Ullah; Loh, Poh Chiang; Blaabjerg, Frede

    2013-01-01

    DGs are usually of different types unlike synchronous generators. This paper presents an autonomous droop scheme that takes into consideration the operating cost, efficiency and emission penalty of each DG since all these factors directly or indirectly contributes to the Total Generation Cost (TGC...

  17. A polling model with an autonomous server

    NARCIS (Netherlands)

    de Haan, Roland; Boucherie, Richardus J.; van Ommeren, Jan C.W.

    2009-01-01

    This paper considers polling systems with an autonomous server that remain at a queue for an exponential amount of time before moving to a next queue incurring a generally distributed switch-over time. The server remains at a queue until the exponential visit time expires, also when the queue

  18. Diabetic cardiovascular autonomic neuropathy: clinical implications.

    Science.gov (United States)

    Karayannis, Georgios; Giamouzis, Gregory; Cokkinos, Dennis V; Skoularigis, John; Triposkiadis, Filippos

    2012-06-01

    Diabetic cardiovascular autonomic neuropathy (DCAN), the impairment of the autonomic balance of the cardiovascular system in the setting of diabetes mellitus (DM), is frequently observed in both Type 1 and 2 DM, has detrimental effects on the quality of life and portends increased mortality. Clinical manifestations include: resting heart rate disorders, exercise intolerance, intraoperative cardiovascular lability, orthostatic alterations in heart rate and blood pressure, QT-interval prolongation, abnormal diurnal and nocturnal blood pressure variation, silent myocardial ischemia and diabetic cardiomyopathy. Clinical tests for autonomic nervous system evaluation, heart rate variability analysis, autonomic innervation imaging techniques, microneurography and baroreflex analysis are the main diagnostic tools for DCAN detection. Aldose reductase inhibitors and antioxidants may be helpful in DCAN therapy, but a regular, more generalized and multifactorial approach should be adopted with inclusion of lifestyle modifications, strict glycemic control and treatment of concomitant traditional cardiovascular risk factors, in order to achieve the best therapeutic results. In the present review, the authors provide aspects of DCAN pathophysiology, clinical presentation, diagnosis and an algorithm regarding the evaluation and management of DCAN in DM patients.

  19. Applying Energy Autonomous Robots for Dike Inspection

    NARCIS (Netherlands)

    Dresscher, Douwe; de Vries, Theodorus J.A.; Stramigioli, Stefano

    2015-01-01

    This article presents an exploratory study of an energy-autonomous robot that can be deployed on the Dutch dykes. Based on theory in energy harvesting from sun and wind and the energy-cost of locomotion an analytic expression to determine the feasible daily operational time of such a vehicle is

  20. Autonomic changes in fibromyalgia: Clinical and ...

    African Journals Online (AJOL)

    Noha El-Sawy

    2012-03-14

    Mar 14, 2012 ... Fibromyalgia;. Tilt table test;. Standing and supine blood pressure and heart rate;. Sympathetic skin response. Abstract Background: Autonomic nervous ... Depression(HRSD) and 4 – functional status by Fibromyalgia impact questionnaire (FIQ). ..... may affect the sleep pattern and psychological state of the.

  1. Requirement analysis for autonomous systems and intelligent ...

    African Journals Online (AJOL)

    user

    This control architecture is based upon the requirements identified in the first part. We also present development of a software framework to test such flexible control architectures. Keywords: Electric power system, distributed control, autonomous systems, intelligent agents. 1. Introduction. Electric power systems is one of the ...

  2. A Multifunctional Coating for Autonomous Corrosion Control

    Science.gov (United States)

    Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott t.

    2011-01-01

    Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it. The multi-functionality of the coating is based on microencapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of existing microcapsulation designs, the corrosion controlled release function that triggers the delivery of corrosion indicators and inhibitors on demand, only when and where needed. Microencapsulation of self-healing agents for autonomous repair of mechanical damage to the coating is also being pursued. Corrosion indicators, corrosion inhibitors, as well as self-healing agents, have been encapsulated and dispersed into several paint systems to test the corrosion detection, inhibition, and self-healing properties of the coating. Key words: Corrosion, coating, autonomous corrosion control, corrosion indication, corrosion inhibition, self-healing coating, smart coating, multifunctional coating, microencapsulation.

  3. A universal projective synchronization of general autonomous ...

    Indian Academy of Sciences (India)

    2015-11-27

    Home; Journals; Pramana – Journal of Physics; Volume 79; Issue 6. A universal projective synchronization of general autonomous chaotic system ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November 27, 2015.

  4. Pacific Reef Assessment and Monitoring Program: Assessing and Monitoring Cryptic Reef Diversity of Colonizing Marine Invertebrates using Autonomous Reef Monitoring Structures (ARMS) Deployed at Coral Reef Sites across the U.S. Pacific from 2008-02-06 to 2012-05-18 (NCEI Accession 0162469)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term program for sustainable management and conservation of coral reef ecosystems, from 2008, Autonomous Reef Monitoring Structures (ARMS) have...

  5. Initial sensorimotor and delayed autonomic neuropathy in acute thallium poisoning.

    Science.gov (United States)

    Nordentoft, T; Andersen, E B; Mogensen, P H

    1998-06-01

    In a 27-year old male with acute thallium poisoning, signs of initially severe sensorimotor neuropathy with complete remission after two weeks were demonstrated. Signs of cardiovascular autonomic neuropathy were initially absent, but developed after a latency period of one week with marked improvement after seven months. Delayed autonomic neuropathy may be caused by a late affection of small unmyelinated autonomic nerve fibers.

  6. Nursing leadership and autonomous professional practice of registered nurses.

    Science.gov (United States)

    Ferguson-Paré, M

    1998-01-01

    Autonomous professional practice continues to be elusive for registered nurses. Autonomous professional practice implies that nurses would be free to determine the procedures for carrying out their nursing work. In other works, they would be able to make independent decisions about their own nursing practice. This article reports research that describes the nature of nursing leadership that supports autonomous professional practice of registered nurses.

  7. Simulation of Aircraft Sortie Generation Under an Autonomic Logistics System

    Science.gov (United States)

    2016-12-01

    kind of on-board artificial autonomic nervous system which is vital for AL operations. Through the use of intelligent reasoners, PHM detects, isolates...SIMULATION OF AIRCRAFT SORTIE GENERATION UNDER AN AUTONOMIC LOGISTICS SYSTEM THESIS Gunduz...Government. AFIT-ENS-MS-16-D-052 SIMULATION OF AIRCRAFT SORTIE GENERATION UNDER AN AUTONOMIC LOGISTICS SYSTEM THESIS Presented to

  8. Advanced Autonomous Systems for Space Operations

    Science.gov (United States)

    Gross, A. R.; Smith, B. D.; Muscettola, N.; Barrett, A.; Mjolssness, E.; Clancy, D. J.

    2002-01-01

    New missions of exploration and space operations will require unprecedented levels of autonomy to successfully accomplish their objectives. Inherently high levels of complexity, cost, and communication distances will preclude the degree of human involvement common to current and previous space flight missions. With exponentially increasing capabilities of computer hardware and software, including networks and communication systems, a new balance of work is being developed between humans and machines. This new balance holds the promise of not only meeting the greatly increased space exploration requirements, but simultaneously dramatically reducing the design, development, test, and operating costs. New information technologies, which take advantage of knowledge-based software, model-based reasoning, and high performance computer systems, will enable the development of a new generation of design and development tools, schedulers, and vehicle and system health management capabilities. Such tools will provide a degree of machine intelligence and associated autonomy that has previously been unavailable. These capabilities are critical to the future of advanced space operations, since the science and operational requirements specified by such missions, as well as the budgetary constraints will limit the current practice of monitoring and controlling missions by a standing army of ground-based controllers. System autonomy capabilities have made great strides in recent years, for both ground and space flight applications. Autonomous systems have flown on advanced spacecraft, providing new levels of spacecraft capability and mission safety. Such on-board systems operate by utilizing model-based reasoning that provides the capability to work from high-level mission goals, while deriving the detailed system commands internally, rather than having to have such commands transmitted from Earth. This enables missions of such complexity and communication` distances as are not

  9. Behavioral and biological effects of autonomous versus scheduled mission management in simulated space-dwelling groups

    Science.gov (United States)

    Roma, Peter G.; Hursh, Steven R.; Hienz, Robert D.; Emurian, Henry H.; Gasior, Eric D.; Brinson, Zabecca S.; Brady, Joseph V.

    2011-05-01

    Logistical constraints during long-duration space expeditions will limit the ability of Earth-based mission control personnel to manage their astronaut crews and will thus increase the prevalence of autonomous operations. Despite this inevitability, little research exists regarding crew performance and psychosocial adaptation under such autonomous conditions. To this end, a newly-initiated study on crew management systems was conducted to assess crew performance effectiveness under rigid schedule-based management of crew activities by Mission Control versus more flexible, autonomous management of activities by the crews themselves. Nine volunteers formed three long-term crews and were extensively trained in a simulated planetary geological exploration task over the course of several months. Each crew then embarked on two separate 3-4 h missions in a counterbalanced sequence: Scheduled, in which the crews were directed by Mission Control according to a strict topographic and temporal region-searching sequence, and Autonomous, in which the well-trained crews received equivalent baseline support from Mission Control but were free to explore the planetary surface as they saw fit. Under the autonomous missions, performance in all three crews improved (more high-valued geologic samples were retrieved), subjective self-reports of negative emotional states decreased, unstructured debriefing logs contained fewer references to negative emotions and greater use of socially-referent language, and salivary cortisol output across the missions was attenuated. The present study provides evidence that crew autonomy may improve performance and help sustain if not enhance psychosocial adaptation and biobehavioral health. These controlled experimental data contribute to an emerging empirical database on crew autonomy which the international astronautics community may build upon for future research and ultimately draw upon when designing and managing missions.

  10. Pulmonary vein region ablation in experimental vagal atrial fibrillation: role of pulmonary veins versus autonomic ganglia.

    Science.gov (United States)

    Lemola, Kristina; Chartier, Denis; Yeh, Yung-Hsin; Dubuc, Marc; Cartier, Raymond; Armour, Andrew; Ting, Michael; Sakabe, Masao; Shiroshita-Takeshita, Akiko; Comtois, Philippe; Nattel, Stanley

    2008-01-29

    Pulmonary vein (PV) -encircling radiofrequency ablation frequently is effective in vagal atrial fibrillation (AF), and there is evidence that PVs may be particularly prone to cholinergically induced arrhythmia mechanisms. However, PV ablation procedures also can affect intracardiac autonomic ganglia. The present study examined the relative role of PVs versus peri-PV autonomic ganglia in an experimental vagal AF model. Cholinergic AF was studied under carbachol infusion in coronary perfused canine left atrial PV preparations in vitro and with cervical vagal stimulation in vivo. Carbachol caused dose-dependent AF promotion in vitro, which was not affected by excision of all PVs. Sustained AF could be induced easily in all dogs during vagal nerve stimulation in vivo both before and after isolation of all PVs with encircling lesions created by a bipolar radiofrequency ablation clamp device. PV elimination had no effect on atrial effective refractory period or its responses to cholinergic stimulation. Autonomic ganglia were identified by bradycardic and/or tachycardic responses to high-frequency subthreshold local stimulation. Ablation of the autonomic ganglia overlying all PV ostia suppressed the effective refractory period-abbreviating and AF-promoting effects of cervical vagal stimulation, whereas ablation of only left- or right-sided PV ostial ganglia failed to suppress AF. Dominant-frequency analysis suggested that the success of ablation in suppressing vagal AF depended on the elimination of high-frequency driver regions. Intact PVs are not needed for maintenance of experimental cholinergic AF. Ablation of the autonomic ganglia at the base of the PVs suppresses vagal responses and may contribute to the effectiveness of PV-directed ablation procedures in vagal AF.

  11. Exercise and the autonomic nervous system.

    Science.gov (United States)

    Fu, Qi; Levine, Benjamin D

    2013-01-01

    The autonomic nervous system plays a crucial role in the cardiovascular response to acute (dynamic) exercise in animals and humans. During exercise, oxygen uptake is a function of the triple-product of heart rate and stroke volume (i.e., cardiac output) and arterial-mixed venous oxygen difference (the Fick principle). The degree to which each of the variables can increase determines maximal oxygen uptake (V˙O2max). Both "central command" and "the exercise pressor reflex" are important in determining the cardiovascular response and the resetting of the arterial baroreflex during exercise to precisely match systemic oxygen delivery with metabolic demand. In general, patients with autonomic disorders have low levels of V˙O2max, indicating reduced physical fitness and exercise capacity. Moreover, the vast majority of the patients have blunted or abnormal cardiovascular response to exercise, especially during maximal exercise. There is now convincing evidence that some of the protective and therapeutic effects of chronic exercise training are related to the impact on the autonomic nervous system. Additionally, training induced improvement in vascular function, blood volume expansion, cardiac remodeling, insulin resistance and renal-adrenal function may also contribute to the protection and treatment of cardiovascular, metabolic and autonomic disorders. Exercise training also improves mental health, helps to prevent depression, and promotes or maintains positive self-esteem. Moderate-intensity exercise at least 30 minutes per day and at least 5 days per week is recommended for the vast majority of people. Supervised exercise training is preferable to maximize function capacity, and may be particularly important for patients with autonomic disorders. © 2013 Elsevier B.V. All rights reserved.

  12. Ultraestrutura da espermatogênese do tamoatá, Hoplosternum littorale (Hancock (Teleostei, Callichthyidae do rio Amazonas Ultrastructure of the spermatogenesis of the fish, Hoplosternum littorale (Hancock (Teleostei, Callichthyidae of the Amazon river

    Directory of Open Access Journals (Sweden)

    E Matos

    1993-01-01

    Full Text Available Sequential cytological modifications of Hoplosternum littorale (Hancock spermatogenesis were studied with electron microscopy from the spermatocyte to the mature spermatozoon. Five stages of spermatical maturation were described. The spermatozoon is one of the primitive tupe, with head without acrosome and a tail with a type pattern.

  13. Sustainable Scientists

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Evan

    2008-12-31

    Scientists are front and center in quantifying and solving environmental problems. Yet, as a spate of recent news articles in scientific journals point out, much can be done to enhance sustainability within the scientific enterprise itself, particularly by trimming the energy use associated with research facilities and the equipment therein (i,ii,iii, iv). Sponsors of research unwittingly spend on the order of $10 billion each year on energy in the U.S. alone, and the underlying inefficiencies drain funds from the research enterprise while causing 80 MT CO2-equivalent greenhouse-gas emissions (see Box). These are significant sums considering the opportunity costs in terms of the amount of additional research that could be funded and emissions that could be reduced if the underlying energy was used more efficiently. By following commercially proven best practices in facility design and operation, scientists--and the sponsors of science--can cost-effectively halve these costs, while doing their part to put society on alow-carbon diet.

  14. Sustainable agriculture - selected papers

    OpenAIRE

    Krasowicz, Stanisław; Wrzaszcz, Wioletta; Zegar, Jozef St.

    2007-01-01

    The concept of research on socially sustainable agriculture. Features of sustainable agriculture. Sustainability of private farms in the light of selected criteria. Subsistence agricultural holdings and the sustainable development of agriculture. Sustainable farms in the light of the FADN data. Description of organic holdings in Poland.

  15. Transformation of the System of Values of Autonomous Learning for English Acquisition in Blended E-Studies for Adults: A Holistic Fractal Model

    Science.gov (United States)

    Bojare, Inara; Skrinda, Astrida

    2016-01-01

    The present study is aimed at creating a holistic fractal model (HFM) of autonomous learning for English acquisition in a blended environment of e-studies in adult non-formal education on the basis of the theories and paradigms of philosophy, psychology and education for sustainable development to promote the development of adult learners'…

  16. Sustainable NREL - Site Sustainability Plan FY 2015

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2015-01-01

    NREL's Site Sustainability Plan FY 2015 reports on sustainability plans for the lab for the year 2015 based on Executive Order Goals and provides the status on planned actions cited in the FY 2014 report.

  17. Research of autonomous landing control of unmanned combat air vehicle

    Science.gov (United States)

    Li, Shaoyan; Chen, Zongji

    2003-09-01

    This paper is to present a robust controller design method for developing autonomous landing systems of Unmanned Combat Air Vehicle (UCAV). We first analyze the characteristic of autonomous landing of UCAV, and put forward its landing performance specifications. Structure singular value μ| synthesis is used to develop autonomous landing systems to accurately follow the pre-designed ideal landing track or online generated optimal landing track. The robust performance of system is analyzed. The simulation results demonstrate that the designed autonomous landing system satisfies the performance requirements of autonomous landing of UCAV when there are uncertainties of UCAV aircraft model, measurement noises and exogenous disturbances.

  18. Apoptosis and Self-Destruct: A Contribution to Autonomic Agents?

    Science.gov (United States)

    Sterritt, Roy; Hinchey, Mike

    2004-01-01

    Autonomic Computing (AC), a self-managing systems initiative based on the biological metaphor of the autonomic nervous system, is increasingly gaining momentum as the way forward in designing reliable systems. Agent technologies have been identified as a key enabler for engineering autonomicity in systems, both in terms of retrofitting autonomicity into legacy systems and designing new systems. The AC initiative provides an opportunity to consider other biological systems and principles in seeking new design strategies. This paper reports on one such investigation; utilizing the apoptosis metaphor of biological systems to provide a dynamic health indicator signal between autonomic agents.

  19. Autonomous Orbit Navigator Development, Using GPS, Applied to Autonomous Orbit Control

    Science.gov (United States)

    Galski, Roberto Luiz

    2002-01-01

    The appearance of modem global positioning systems motivated the study and development of precise and robust systems for autonomous orbit determination of artificial satellites. These systems maintain, independently from human intervention from the ground, a precise knowledge of the satellite orbital state, through the processing of the information, autonomously generated on-board, by a receiver of the positioning system used. One of the major motivations for the research and development of autonomous navigators, is the availability of real time information about the position and velocity of the satellite, required, for instance, in earth observation missions, for interpretation and analysis of the generated images. The appearance of global positioning systems and the consequent development of autonomous navigators, by making available onboard space vehicles, updated orbit estimations, with good accuracy level, made feasible the research and development of orbit autonomous control procedures. It allowed the orbital maneuvers execution process to be performed in a way totally independent from ground human intervention. Whereas the satellite attitude control reached a high level of autonomy, due to the fact that the attitude measurements are, in general, naturally generated on-board the spacecraft, the orbit control is still now almost totally planned and executed from ground commanded actions. The proposed work consists of the study, development, simulation and analysis of a simplified navigator coupled to an autonomous orbit control system, applied to the China-Brazil Earth Resources Satellites (CBERS). At first, an autonomous orbit determination procedure is developed and analyzed. Its objective is to improve the coarse geometric solution provided by Global Positioning System (GPS) receivers. This will be done by directly using this solution as input (observation) for a real time Kalman filtering process. The orbital state vector will be extended in order to

  20. Indicators for environmental sustainability

    DEFF Research Database (Denmark)

    Dong, Yan; Hauschild, Michael Zwicky

    2017-01-01

    Decision making on sustainable consumption and production requires scientifically based information on sustainability. Different environmental sustainability targets exist for specific decision problems. To observe how well these targets are met, relevant environmental indicators are needed...