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Sample records for moles mammalia afrotheria

  1. Brain Volume of the Newly-Discovered Species Rhynchocyon udzungwensis (Mammalia: Afrotheria: Macroscelidea): Implications for Encephalization in Sengis

    PubMed Central

    Kaufman, Jason A.; Turner, Gregory H.; Holroyd, Patricia A.; Rovero, Francesco; Grossman, Ari

    2013-01-01

    The Gray-faced Sengi (Rhynchocyon udzungwensis) is a newly-discovered species of sengi (elephant-shrew) and is the largest known extant representative of the order Macroscelidea. The discovery of R. udzungwensis provides an opportunity to investigate the scaling relationship between brain size and body size within Macroscelidea, and to compare this allometry among insectivorous species of Afrotheria and other eutherian insectivores. We performed a spin-echo magnetic resonance imaging (MRI) scan on a preserved adult specimen of R. udzungwensis using a 7-Tesla high-field MR imaging system. The brain was manually segmented and its volume was compiled into a dataset containing previously-published allometric data on 56 other species of insectivore-grade mammals including representatives of Afrotheria, Soricomorpha and Erinaceomorpha. Results of log-linear regression indicate that R. udzungwensis exhibits a brain size that is consistent with the allometric trend described by other members of its order. Inter-specific comparisons indicate that macroscelideans as a group have relatively large brains when compared with similarly-sized terrestrial mammals that also share a similar diet. This high degree of encephalization within sengis remains robust whether sengis are compared with closely-related insectivorous afrotheres, or with more-distantly-related insectivorous laurasiatheres. PMID:23516530

  2. Brain volume of the newly-discovered species Rhynchocyon udzungwensis (Mammalia: Afrotheria: Macroscelidea): implications for encephalization in sengis.

    PubMed

    Kaufman, Jason A; Turner, Gregory H; Holroyd, Patricia A; Rovero, Francesco; Grossman, Ari

    2013-01-01

    The Gray-faced Sengi (Rhynchocyon udzungwensis) is a newly-discovered species of sengi (elephant-shrew) and is the largest known extant representative of the order Macroscelidea. The discovery of R. udzungwensis provides an opportunity to investigate the scaling relationship between brain size and body size within Macroscelidea, and to compare this allometry among insectivorous species of Afrotheria and other eutherian insectivores. We performed a spin-echo magnetic resonance imaging (MRI) scan on a preserved adult specimen of R. udzungwensis using a 7-Tesla high-field MR imaging system. The brain was manually segmented and its volume was compiled into a dataset containing previously-published allometric data on 56 other species of insectivore-grade mammals including representatives of Afrotheria, Soricomorpha and Erinaceomorpha. Results of log-linear regression indicate that R. udzungwensis exhibits a brain size that is consistent with the allometric trend described by other members of its order. Inter-specific comparisons indicate that macroscelideans as a group have relatively large brains when compared with similarly-sized terrestrial mammals that also share a similar diet. This high degree of encephalization within sengis remains robust whether sengis are compared with closely-related insectivorous afrotheres, or with more-distantly-related insectivorous laurasiatheres.

  3. Moles

    MedlinePlus

    ... sizes and shapes. Special cells that contain the pigment melanin cause the brown color. Facial moles are ... They also leave nevus cells behind and the pigment often seems to reappear. Back to Index The ...

  4. Digital dissection of the masticatory muscles of the naked mole-rat, Heterocephalus glaber (Mammalia, Rodentia)

    PubMed Central

    Faulkes, Chris G.

    2014-01-01

    The naked mole-rat, Heterocephalus glaber, of the family Bathyergidae is a subterranean rodent that feeds on underground roots and tubers and digs extensive tunnel systems with its incisors. It is a highly unusual mammal with regard to its social structure, longevity, pain insensitivity and cancer resistance, all of which have made it the subject of a great deal of research in recent years. Yet, much of the basic anatomy of this species remains undocumented. In this paper, we describe the morphology of the jaw-closing musculature of the naked mole-rat, as revealed by contrast-enhanced micro-computed tomography. This technique uses an iodine stain to enable the imaging of soft tissues with microCT. The iodine-enhanced scans were used to create 3D reconstructions of the naked mole-rat masticatory muscles from which muscle masses were calculated. The jaw-closing musculature of Heterocephalus glaber is relatively very large compared to other rodents and is dominated by the superficial masseter, the deep masseter and the temporalis. The temporalis in particular is large for a rodent, covering the entirety of the braincase and much of the rear part of the orbit. The morphology of the masseter complex described here differs from two other published descriptions of bathyergid masticatory muscles, but is more similar to the arrangement seen in other rodent families. The zygomaticomandibularis (ZM) muscle does not protrude through the infraorbital foramen on to the rostrum and thus the naked mole-rat should be considered protrogomorphous rather than hystricomorphous, and the morphology is consistent with secondarily lost hystricomorphy as has been previously suggested for Bathyergidae. Overall, the morphology of the masticatory musculature indicates a species with a high bite force and a wide gape–both important adaptations for a life dominated by digging with the incisors. PMID:25024917

  5. Digital dissection of the masticatory muscles of the naked mole-rat, Heterocephalus glaber (Mammalia, Rodentia).

    PubMed

    Cox, Philip G; Faulkes, Chris G

    2014-01-01

    The naked mole-rat, Heterocephalus glaber, of the family Bathyergidae is a subterranean rodent that feeds on underground roots and tubers and digs extensive tunnel systems with its incisors. It is a highly unusual mammal with regard to its social structure, longevity, pain insensitivity and cancer resistance, all of which have made it the subject of a great deal of research in recent years. Yet, much of the basic anatomy of this species remains undocumented. In this paper, we describe the morphology of the jaw-closing musculature of the naked mole-rat, as revealed by contrast-enhanced micro-computed tomography. This technique uses an iodine stain to enable the imaging of soft tissues with microCT. The iodine-enhanced scans were used to create 3D reconstructions of the naked mole-rat masticatory muscles from which muscle masses were calculated. The jaw-closing musculature of Heterocephalus glaber is relatively very large compared to other rodents and is dominated by the superficial masseter, the deep masseter and the temporalis. The temporalis in particular is large for a rodent, covering the entirety of the braincase and much of the rear part of the orbit. The morphology of the masseter complex described here differs from two other published descriptions of bathyergid masticatory muscles, but is more similar to the arrangement seen in other rodent families. The zygomaticomandibularis (ZM) muscle does not protrude through the infraorbital foramen on to the rostrum and thus the naked mole-rat should be considered protrogomorphous rather than hystricomorphous, and the morphology is consistent with secondarily lost hystricomorphy as has been previously suggested for Bathyergidae. Overall, the morphology of the masticatory musculature indicates a species with a high bite force and a wide gape-both important adaptations for a life dominated by digging with the incisors.

  6. Genome size: a novel genomic signature in support of Afrotheria.

    PubMed

    Redi, Carlo Alberto; Garagna, Silvia; Zuccotti, Maurizio; Capanna, Ernesto

    2007-04-01

    Molecular phylogenetic analyses suggest an emerging phylogeny for the extant Placentalia (eutherian) that radically departs from morphologically based constructions of the past. Placental mammals are partitioned into four supraordinal clades: Afrotheria, Xenarthra, Laurasiatheria, and Euarchontoglires. Afrotheria form an endemic African clade that includes elephant shrews, golden moles, tenrecs, aardvarks, hyraxes, elephants, dugongs, and manatees. Datamining databases of genome size (GS) shows that till today just one afrotherian GS has been evaluated, that of the aardvark Orycteropus afer. We show that the GSs of six selected representatives across the Afrotheria supraordinal group are among the highest for the extant Placentalia, providing a novel genomic signature of this enigmatic group. The mean GS value of Afrotheria, 5.3 +/- 0.7 pg, is the highest reported for the extant Placentalia. This should assist in planning new genome sequencing initiatives.

  7. A new form of the mole vole Ellobius tancrei Blasius, 1884 (Mammalia, Rodentia) with the lowest chromosome number

    PubMed Central

    Bakloushinskaya, Irina; Romanenko, Svetlana A.; Serdukova, Natalia A.; Graphodatsky, Alexander S.; Lyapunova, Elena A.

    2013-01-01

    Abstract The subterranean mole vole, Ellobius tancrei, with aspecific variability in autosomes (2n = 31–54) and unusual sex chromosomes (XX in males and females), represents an amazing model for studying the role of chromosome changes in speciation. New materials from the upper reaches of the Surkhob River in the Pamiro-Alay mountains resulted in the discovery of a new form with 2n = 30. The application of Zoo-FISH and G-banding methods allowed the detection of 13 pairs of autosomes as Robertsonian metacentrics originated after fusions of acrocentrics of an assumed ancestral karyotype of Ellobius tancrei with 2n = 54. The sex chromosomes (XX, in both sexes) and one pair of acrocentric autosomes are the only acrocentrics in this karyotype, and the set with 2n = 30 possesses the lowest possible chromosome number among populations of Ellobius tancrei. PMID:24260698

  8. Placentation in species of phylogenetic importance: the Afrotheria.

    PubMed

    Carter, A M; Enders, A C; Künzle, H; Oduor-Okelo, D; Vogel, P

    2004-07-01

    Afrotheria, one of four mammalian superorders, comprises elephants, sea cows, hyraxes, aardvark, elephant shrews, tenrecs and golden moles. Their placentas either form an equatorial band or are discoid in shape. The interhemal region, separating fetal and maternal blood, is endotheliochorial in elephants, aardvark and possibly the sea cows, but hemochorial in the remaining orders. There is a secondary epitheliochorial placenta in elephant shrews while a similar structure in tenrecs erodes maternal tissues. Specialized hemophagous regions are a striking characteristic of some of these placentas yet absent in hyraxes, elephant shrews, and golden moles. It is possible that the common ancestor of the Afrotheria had an endotheliochorial placenta. Establishment of a hemochorial condition, as seen in rock hyraxes, elephant shrews, tenrecs, and golden moles, would be a more recent development. The elephant, manatee, and aardvark all have circumferential placentas. Thus the formation of a discoid placenta with a more or less extensive secondary placenta in elephant shrews and tenrecs would also be a derived state.

  9. Chromosomal instability in Afrotheria: fragile sites, evolutionary breakpoints and phylogenetic inference from genome sequence assemblies

    PubMed Central

    Ruiz-Herrera, Aurora; Robinson, Terence J

    2007-01-01

    Background Extant placental mammals are divided into four major clades (Laurasiatheria, Supraprimates, Xenarthra and Afrotheria). Given that Afrotheria is generally thought to root the eutherian tree in phylogenetic analysis of large nuclear gene data sets, the study of the organization of the genomes of afrotherian species provides new insights into the dynamics of mammalian chromosomal evolution. Here we test if there are chromosomal bands with a high tendency to break and reorganize in Afrotheria, and by analyzing the expression of aphidicolin-induced common fragile sites in three afrotherian species, whether these are coincidental with recognized evolutionary breakpoints. Results We described 29 fragile sites in the aardvark (OAF) genome, 27 in the golden mole (CAS), and 35 in the elephant-shrew (EED) genome. We show that fragile sites are conserved among afrotherian species and these are correlated with evolutionary breakpoints when compared to the human (HSA) genome. Inddition, by computationally scanning the newly released opossum (Monodelphis domestica) and chicken sequence assemblies for use as outgroups to Placentalia, we validate the HSA 3/21/5 chromosomal synteny as a rare genomic change that defines the monophyly of this ancient African clade of mammals. On the other hand, support for HSA 1/19p, which is also thought to underpin Afrotheria, is currently ambiguous. Conclusion We provide evidence that (i) the evolutionary breakpoints that characterise human syntenies detected in the basal Afrotheria correspond at the chromosomal band level with fragile sites, (ii) that HSA 3p/21 was in the amniote ancestor (i.e., common to turtles, lepidosaurs, crocodilians, birds and mammals) and was subsequently disrupted in the lineage leading to marsupials. Its expansion to include HSA 5 in Afrotheria is unique and (iii) that its fragmentation to HSA 3p/21 + HSA 5/21 in elephant and manatee was due to a fission within HSA 21 that is probably shared by all

  10. Early Tertiary mammals from North Africa reinforce the molecular Afrotheria clade

    PubMed Central

    Tabuce, Rodolphe; Marivaux, Laurent; Adaci, Mohammed; Bensalah, Mustapha; Hartenberger, Jean-Louis; Mahboubi, Mohammed; Mebrouk, Fateh; Tafforeau, Paul; Jaeger, Jean-Jacques

    2007-01-01

    The phylogenetic pattern and timing of the radiation of mammals, especially the geographical origins of major crown clades, are areas of controversy among molecular biologists, morphologists and palaeontologists. Molecular phylogeneticists have identified an Afrotheria clade, which includes several taxa as different as tenrecs (Tenrecidae), golden moles (Chrysochloridae), elephant-shrews (Macroscelididae), aardvarks (Tubulidentata) and paenungulates (elephants, sea cows and hyracoids). Molecular data also suggest a Cretaceous African origin for Afrotheria within Placentalia followed by a long period of endemic evolution on the Afro-Arabian continent after the mid-Cretaceous Gondwanan breakup (approx. 105–25 Myr ago). However, there was no morphological support for such a natural grouping so far. Here, we report new dental and postcranial evidence of Eocene stem hyrax and macroscelidid from North Africa that, for the first time, provides a congruent phylogenetic view with the molecular Afrotheria clade. These new fossils imply, however, substantial changes regarding the historical biogeography of afrotheres. Their long period of isolation in Africa, as assumed by molecular inferences, is now to be reconsidered inasmuch as Eocene paenungulates and elephant-shrews are here found to be related to some Early Tertiary Euramerican ‘hyopsodontid condylarths’ (archaic hoofed mammals). As a result, stem members of afrotherian clades are not strictly African but also include some Early Paleogene Holarctic mammals. PMID:17329227

  11. Bone Inner Structure Suggests Increasing Aquatic Adaptations in Desmostylia (Mammalia, Afrotheria)

    PubMed Central

    Hayashi, Shoji; Houssaye, Alexandra; Nakajima, Yasuhisa; Chiba, Kentaro; Ando, Tatsuro; Sawamura, Hiroshi; Inuzuka, Norihisa; Kaneko, Naotomo; Osaki, Tomohiro

    2013-01-01

    Background The paleoecology of desmostylians has been discussed controversially with a general consensus that desmostylians were aquatic or semi-aquatic to some extent. Bone microanatomy can be used as a powerful tool to infer habitat preference of extinct animals. However, bone microanatomical studies of desmostylians are extremely scarce. Methodology/Principal Findings We analyzed the histology and microanatomy of several desmostylians using thin-sections and CT scans of ribs, humeri, femora and vertebrae. Comparisons with extant mammals allowed us to better understand the mode of life and evolutionary history of these taxa. Desmostylian ribs and long bones generally lack a medullary cavity. This trait has been interpreted as an aquatic adaptation among amniotes. Behemotops and Paleoparadoxia show osteosclerosis (i.e. increase in bone compactness), and Ashoroa pachyosteosclerosis (i.e. combined increase in bone volume and compactness). Conversely, Desmostylus differs from these desmostylians in displaying an osteoporotic-like pattern. Conclusions/Significance In living taxa, bone mass increase provides hydrostatic buoyancy and body trim control suitable for poorly efficient swimmers, while wholly spongy bones are associated with hydrodynamic buoyancy control in active swimmers. Our study suggests that all desmostylians had achieved an essentially, if not exclusively, aquatic lifestyle. Behemotops, Paleoparadoxia and Ashoroa are interpreted as shallow water swimmers, either hovering slowly at a preferred depth, or walking on the bottom, and Desmostylus as a more active swimmer with a peculiar habitat and feeding strategy within Desmostylia. Therefore, desmostylians are, with cetaceans, the second mammal group showing a shift from bone mass increase to a spongy inner organization of bones in their evolutionary history. PMID:23565143

  12. Chromosome painting among Proboscidea, Hyracoidea and Sirenia: Support for Paenungulata (Afrotheria, Mammalia) but not Tethytheria

    USGS Publications Warehouse

    Pardini, A.T.; O'Brien, P. C. M.; Fu, B.; Bonde, R.K.; Elder, F.F.B.; Ferguson-Smith, M. A.; Yang, F.; Robinson, T.J.

    2007-01-01

    Despite marked improvements in the interpretation of systematic relationships within Eutheria, particular nodes, including Paenungulata (Hyracoidea, Sirenia and Proboscidea), remain ambiguous. The combination of a rapid radiation, a deep divergence and an extensive morphological diversification has resulted in a limited phylogenetic signal confounding resolution within this clade both at the morphological and nucleotide levels. Cross-species chromosome painting was used to delineate regions of homology between Loxodonta africana (2n = 56), Procavia capensis (2n=54), Trichechus manatus latirostris (2n = 48) and an outgroup taxon, the aardvark (Orycteropus afer, 2n = 20). Changes specific to each lineage were identified and although the presence of a minimum of 11 synapomorphies confirmed the monophyly of Paenungulata, no change characterizing intrapaenungulate relationships was evident. The reconstruction of an ancestral paenungulate karyotype and the estimation of rates of chromosomal evolution indicate a reduced rate of genomic repatterning following the paenungulate radiation. In comparison to data available for other mammalian taxa, the paenungulate rate of chromosomal evolution is slow to moderate. As a consequence, the absence of a chromosomal character uniting two paenungulates (at the level of resolution characterized in this study) may be due to a reduced rate of chromosomal change relative to the length of time separating successive divergence events. ?? 2007 The Royal Society.

  13. Chromosome painting in the manatee supports Afrotheria and Paenungulata

    USGS Publications Warehouse

    Kellogg, Margaret E.; Burkett, Sandra; Dennis, Thomas R.; Stone, Gary; Gray, Brian A.; McGuire, Peter M.; Zori, Roberto T.; Stanyon, Roscoe

    2007-01-01

    There are five derived chromosome traits that strongly link elephants with manatees in Tethytheria and give implicit support to Paenungulata: the associations 2/3, 3/13, 8/22, 18/19 and the loss of the ancestral eutherian 4/8 association. It would be useful to test these conclusions with chromosome painting in hyraxes. The manatee chromosome painting data confirm that the associations 1/19 and 5/21 phylogenetically link afrotherian species and show that Afrotheria is a natural clade. The association 10/12/22 is also ubiquitous in Afrotheria (clade I), present in Laurasiatheria (clade IV), only partially present in Xenarthra (10/12, clade II) and absent in Euarchontoglires (clade III). If Afrotheria is basal to eutherians, this association could be part of the ancestral eutherian karyotype. If afrotherians are not at the root of the eutherian tree, then the 10/12/22 association could be one of a suite of derived associations linking afrotherian taxa.

  14. Genomic inferences from Afrotheria and the evolution of elephants.

    PubMed

    Roca, Alfred L; O'Brien, Stephen J

    2005-12-01

    Recent genetic studies have established that African forest and savanna elephants are distinct species with dissociated cytonuclear genomic patterns, and have identified Asian elephants from Borneo and Sumatra as conservation priorities. Representative of Afrotheria, a superordinal clade encompassing six eutherian orders, the African savanna elephant was among the first mammals chosen for whole-genome sequencing to provide a comparative understanding of the human genome. Elephants have large and complex brains and display advanced levels of social structure, communication, learning and intelligence. The elephant genome sequence might prove useful for comparative genomic studies of these advanced traits, which have appeared independently in only three mammalian orders: primates, cetaceans and proboscideans.

  15. Chromosome painting in the manatee supports Afrotheria and Paenungulata

    PubMed Central

    Kellogg, Margaret E; Burkett, Sandra; Dennis, Thomas R; Stone, Gary; Gray, Brian A; McGuire, Peter M; Zori, Roberto T; Stanyon, Roscoe

    2007-01-01

    Background Sirenia (manatees, dugongs and Stellar's sea cow) have no evolutionary relationship with other marine mammals, despite similarities in adaptations and body shape. Recent phylogenomic results place Sirenia in Afrotheria and with elephants and rock hyraxes in Paenungulata. Sirenia and Hyracoidea are the two afrotherian orders as yet unstudied by comparative molecular cytogenetics. Here we report on the chromosome painting of the Florida manatee. Results The human autosomal and X chromosome paints delimited a total of 44 homologous segments in the manatee genome. The synteny of nine of the 22 human autosomal chromosomes (4, 5, 6, 9, 11, 14, 17, 18 and 20) and the X chromosome were found intact in the manatee. The syntenies of other human chromosomes were disrupted in the manatee genome into two to five segments. The hybridization pattern revealed that 20 (15 unique) associations of human chromosome segments are found in the manatee genome: 1/15, 1/19, 2/3 (twice), 3/7 (twice), 3/13, 3/21, 5/21, 7/16, 8/22, 10/12 (twice), 11/20, 12/22 (three times), 14/15, 16/19 and 18/19. Conclusion There are five derived chromosome traits that strongly link elephants with manatees in Tethytheria and give implicit support to Paenungulata: the associations 2/3, 3/13, 8/22, 18/19 and the loss of the ancestral eutherian 4/8 association. It would be useful to test these conclusions with chromosome painting in hyraxes. The manatee chromosome painting data confirm that the associations 1/19 and 5/21 phylogenetically link afrotherian species and show that Afrotheria is a natural clade. The association 10/12/22 is also ubiquitous in Afrotheria (clade I), present in Laurasiatheria (clade IV), only partially present in Xenarthra (10/12, clade II) and absent in Euarchontoglires (clade III). If Afrotheria is basal to eutherians, this association could be part of the ancestral eutherian karyotype. If afrotherians are not at the root of the eutherian tree, then the 10/12/22 association

  16. Affinities of `hyopsodontids' to elephant shrews and a Holarctic origin of Afrotheria

    NASA Astrophysics Data System (ADS)

    Zack, Shawn P.; Penkrot, Tonya A.; Bloch, Jonathan I.; Rose, Kenneth D.

    2005-03-01

    Macroscelideans (elephant shrews or sengis) are small-bodied (25-540g), cursorial (running) and saltatorial (jumping), insectivorous and omnivorous placental mammals represented by at least 15 extant African species classified in four genera. Macroscelidea is one of several morphologically diverse but predominantly African placental orders classified in the superorder Afrotheria by molecular phylogeneticists. The distribution of modern afrotheres, in combination with a basal position for Afrotheria within Placentalia and molecular divergence-time estimates, has been used to link placental diversification with the mid-Cretaceous separation of South America and Africa. Morphological phylogenetic analyses do not support Afrotheria and the fossil record favours a northern origin of Placentalia. Here we describe fossil postcrania that provide evidence for a close relationship between North American Palaeocene-Eocene apheliscine `hyopsodontid' `condylarths' (early ungulates or hoofed mammals) and extant Macroscelidea. Apheliscine postcranial morphology is consistent with a relationship to other ungulate-like afrotheres (Hyracoidea, Proboscidea) but does not provide support for a monophyletic Afrotheria. As the oldest record of an afrothere clade, identification of macroscelidean relatives in the North American Palaeocene argues against an African origin for Afrotheria, weakening support for linking placental diversification to the break-up of Gondwana.

  17. Genome sizes in afrotheria, xenarthra, euarchontoglires, and laurasiatheria.

    PubMed

    Redi, C A; Zacharias, H; Merani, S; Oliveira-Miranda, M; Aguilera, M; Zuccotti, M; Garagna, S; Capanna, E

    2005-01-01

    Topical literature and Web site databases provide genome sizes for approximately 4,000 animal species, invertebrates and vertebrates, 330 of which are mammals. We provide the genome size for 67 mammalian species, including 51 never reported before. Knowledge of genome size facilitates sequencing projects. The data presented here encompassed 5 Metatheria (order Didelphimorphia) and 62 Eutheria: 15 Xenarthra, 24 Euarchontoglires (Rodentia), as well as 23 Laurasiatheria (22 Chiroptera and 1 species from Perissodactyla). Already available karyotypes supplement the haploid nuclear DNA contents of the respective species. Thus, we established the first comprehensive set of genome size measurements for 15 Xenarthra species (armadillos) and for 12 house-mouse species; each group was previously represented by only one species. The Xenarthra exhibited much larger genomes than the modal 3 pg DNA known for mammals. Within the genus Mus, genome sizes varied between 2.98 pg and 3.68 pg. The 22 bat species we measured support the low 2.63 pg modal value for Chiroptera. In general, the genomes of Euarchontoglires and Laurasiatheria were found being smaller than those of (Afrotheria and) Xenarthra. Interspecific variation in genome sizes is discussed with particular attention to repetitive elements, which probably promoted the adaptation of extant mammals to their environment.

  18. Chemical Principles Revisited: The Mole.

    ERIC Educational Resources Information Center

    Kolb, Doris

    1978-01-01

    Discusses ways of teaching the mole concept in high school chemistry classes. Provides resource information on the mole and Avogadro's Number. Includes an explanation of four methods for measuring Avogadro's Number and instructions on how to use the mole. (MA)

  19. Mole gun injury.

    PubMed

    Pistré, V; Rezzouk, J

    2013-09-01

    A mole gun is a weapon, which is used to trap and kill moles. This report provides an overview of the state of knowledge of mole gun injuries, comparable to blast injuries caused by fireworks, explosive or gunshot. Over a 2-year period, the authors reported their experience with ten hand injuries caused by mole gun. Radial side of the hand was often concerned, particularly the thumb. The authors explain their choices in the management of such lesions. Surgery was performed primarily and a large debridement currently seemed to offer the best outcome for the patient. Blast, crush, burns and lacerations may explain the higher rate of amputation to the digits. A long period of physiotherapy, specifically of the hand, was needed before the patient could return to work. This ballistic hand trauma encountered by surgeons requires knowledge and understanding of these injuries. It should be in accordance with firearms law because of severe injuries encountered and possible lethal wounds.

  20. Mosaics and moles

    PubMed Central

    Sunde, Lone; Niemann, Isa; Hansen, Estrid Staehr; Hindkjaer, Johnny; Degn, Birte; Jensen, Uffe Birk; Bolund, Lars

    2011-01-01

    Hydatidiform mole (HM) is an abnormal human pregnancy, where the placenta presents with vesicular swelling of the chorionic villi. A fetus is either not present, or malformed and not viable. Most moles are diploid androgenetic as if one spermatozoon fertilized an empty oocyte, or triploid with one maternal and two paternal chromosome sets as if two spermatozoa fertilized a normal oocyte. However, diploid moles with both paternal and maternal markers of the nuclear genome have been reported. Among 162 consecutively collected diploid moles, we have earlier found indications of both maternal and paternal genomes in 11. In the present study, we have performed detailed analysis of DNA-markers in tissue and single cells from these 11 HMs. In 3/11, we identified one biparental cell population only, whereas in 8/11, we demonstrated mosaicism: one biparental cell population and one androgenetic cell population. One mosaic mole was followed by persistent trophoblastic disease (PTD). In seven of the mosaics, one spermatozoon appeared to have contributed to the genomes of both cell types. Our observations make it likely that mosaic conceptuses, encompassing an androgenetic cell population, result from various postzygotic abnormalities, including paternal pronuclear duplication, asymmetric cytokinesis, and postzygotic diploidization. This corroborates the suggestion that fertilization of an empty egg is not mandatory for the creation of an androgenetic cell population. Future studies of mosaic conceptuses may disclose details about fertilization, early cell divisions and differentiation. Apparently, only a minority of diploid moles with both paternal and maternal markers are ‘genuine' diploid biparental moles (DiBiparHMs). PMID:21654731

  1. Cranial Remain from Tunisia Provides New Clues for the Origin and Evolution of Sirenia (Mammalia, Afrotheria) in Africa

    PubMed Central

    Benoit, Julien; Adnet, Sylvain; El Mabrouk, Essid; Khayati, Hayet; Ben Haj Ali, Mustapha; Marivaux, Laurent; Merzeraud, Gilles; Merigeaud, Samuel; Vianey-Liaud, Monique; Tabuce, Rodolphe

    2013-01-01

    Sea cows (manatees, dugongs) are the only living marine mammals to feed solely on aquatic plants. Unlike whales or dolphins (Cetacea), the earliest evolutionary history of sirenians is poorly documented, and limited to a few fossils including skulls and skeletons of two genera composing the stem family of Prorastomidae (Prorastomus and Pezosiren). Surprisingly, these fossils come from the Eocene of Jamaica, while stem Hyracoidea and Proboscidea - the putative sister-groups to Sirenia - are recorded in Africa as early as the Late Paleocene. So far, the historical biogeography of early Sirenia has remained obscure given this paradox between phylogeny and fossil record. Here we use X-ray microtomography to investigate a newly discovered sirenian petrosal from the Eocene of Tunisia. This fossil represents the oldest occurrence of sirenians in Africa. The morphology of this petrosal is more primitive than the Jamaican prorastomids’ one, which emphasizes the basal position of this new African taxon within the Sirenia clade. This discovery testifies to the great antiquity of Sirenia in Africa, and therefore supports their African origin. While isotopic analyses previously suggested sirenians had adapted directly to the marine environment, new paleoenvironmental evidence suggests that basal-most sea cows were likely restricted to fresh waters. PMID:23342128

  2. The chromosomes of Afrotheria and their bearing on mammalian genome evolution.

    PubMed

    Svartman, M; Stanyon, R

    2012-01-01

    Afrotheria is the clade of placental mammals that, together with Xenarthra, Euarchontoglires and Laurasiatheria, represents 1 of the 4 main recognized supraordinal eutherian clades. It reunites 6 orders of African origin: Proboscidea, Sirenia, Hyracoidea, Macroscelidea, Afrosoricida and Tubulidentata. The apparently unlikely relationship among such disparate morphological taxa and their possible basal position at the base of the eutherian phylogenetic tree led to a great deal of attention and research on the group. The use of biomolecular data was pivotal in Afrotheria studies, as they were the basis for the recognition of this clade. Although morphological evidence is still scarce, a plethora of molecular data firmly attests to the phylogenetic relationship among these mammals of African origin. Modern cytogenetic techniques also gave a significant contribution to the study of Afrotheria, revealing chromosome signatures for the group as a whole, as well as for some of its internal relationships. The associations of human chromosomes HSA1/19 and 5/21 were found to be chromosome signatures for the group and provided further support for Afrotheria. Additional chromosome synapomorphies were also identified linking elephants and manatees in Tethytheria (the associations HSA2/3, 3/13, 8/22, 18/19 and the lack of HSA4/8) and elephant shrews with the aardvark (HSA2/8, 3/20 and 10/17). Herein, we review the current knowledge on Afrotheria chromosomes and genome evolution. The already available data on the group suggests that further work on this apparently bizarre assemblage of mammals will provide important data to a better understanding on mammalian genome evolution.

  3. The historical biogeography of Mammalia

    PubMed Central

    Springer, Mark S.; Meredith, Robert W.; Janecka, Jan E.; Murphy, William J.

    2011-01-01

    Palaeobiogeographic reconstructions are underpinned by phylogenies, divergence times and ancestral area reconstructions, which together yield ancestral area chronograms that provide a basis for proposing and testing hypotheses of dispersal and vicariance. Methods for area coding include multi-state coding with a single character, binary coding with multiple characters and string coding. Ancestral reconstruction methods are divided into parsimony versus Bayesian/likelihood approaches. We compared nine methods for reconstructing ancestral areas for placental mammals. Ambiguous reconstructions were a problem for all methods. Important differences resulted from coding areas based on the geographical ranges of extant species versus the geographical provenance of the oldest fossil for each lineage. Africa and South America were reconstructed as the ancestral areas for Afrotheria and Xenarthra, respectively. Most methods reconstructed Eurasia as the ancestral area for Boreoeutheria, Euarchontoglires and Laurasiatheria. The coincidence of molecular dates for the separation of Afrotheria and Xenarthra at approximately 100 Ma with the plate tectonic sundering of Africa and South America hints at the importance of vicariance in the early history of Placentalia. Dispersal has also been important including the origins of Madagascar's endemic mammal fauna. Further studies will benefit from increased taxon sampling and the application of new ancestral area reconstruction methods. PMID:21807730

  4. MOLES Information Model

    NASA Astrophysics Data System (ADS)

    Ventouras, Spiros; Lawrence, Bryan; Woolf, Andrew; Cox, Simon

    2010-05-01

    The Metadata Objects for Linking Environmental Sciences (MOLES) model has been developed within the Natural Environment Research Council (NERC) DataGrid project [NERC DataGrid] to fill a missing part of the ‘metadata spectrum'. It is a framework within which to encode the relationships between the tools used to obtain data, the activities which organised their use, and the datasets produced. MOLES is primarily of use to consumers of data, especially in an interdisciplinary context, to allow them to establish details of provenance, and to compare and contrast such information without recourse to discipline-specific metadata or private communications with the original investigators [Lawrence et al 2009]. MOLES is also of use to the custodians of data, providing an organising paradigm for the data and metadata. The work described in this paper is a high-level view of the structure and content of a recent major revision of MOLES (v3.3) carried out as part of a NERC DataGrid extension project. The concepts of MOLES v3.3 are rooted in the harmonised ISO model [Harmonised ISO model] - particularly in metadata standards (ISO 19115, ISO 19115-2) and the ‘Observations and Measurements' conceptual model (ISO 19156). MOLES exploits existing concepts and relationships, and specialises information in these standards. A typical sequence of data capturing involves one or more projects under which a number of activities are undertaken, using appropriate tools and methods to produce the datasets. Following this typical sequence, the relevant metadata can be partitioned into the following main sections - helpful in mapping onto the most suitable standards from the ISO 19100 series. • Project section • Activity section (including both observation acquisition and numerical computation) • Observation section (metadata regarding the methods used to obtained the data, the spatial and temporal sampling regime, quality etc.) • Observation collection section The key concepts in

  5. Iridescent colour production in hairs of blind golden moles (Chrysochloridae).

    PubMed

    Snyder, Holly K; Maia, Rafael; D'Alba, Liliana; Shultz, Allison J; Rowe, Karen M C; Rowe, Kevin C; Shawkey, Matthew D

    2012-06-23

    Relative to other metazoans, the mammalian integument is thought to be limited in colour. In particular, while iridescence is widespread among birds and arthropods, it has only rarely been reported in mammals. Here, we examine the colour, morphology and optical mechanisms in hairs from four species of golden mole (Mammalia: Chrysochloridae) that are characterized by sheens ranging from purple to green. Microspectrophotometry reveals that this colour is weak and variable. Iridescent hairs are flattened and have highly reduced cuticular scales, providing a broad and smooth surface for light reflection. These scales form multiple layers of light and dark materials of consistent thickness, strikingly similar to those in the elytra of iridescent beetles. Optical modelling suggests that the multi-layers produce colour through thin-film interference, and that the sensitivity of this mechanism to slight changes in layer thickness and number explains colour variability. While coloured integumentary structures are typically thought to evolve as sexual ornaments, the blindness of golden moles suggests that the colour may be an epiphenomenon resulting from evolution via other selective factors, including the ability to move and keep clean in dirt and sand.

  6. Phylogenomic data analyses provide evidence that Xenarthra and Afrotheria are sister groups.

    PubMed

    Hallström, Björn M; Kullberg, Morgan; Nilsson, Maria A; Janke, Axel

    2007-09-01

    The phylogenetic positions of the 4 clades, Euarchontoglires, Laurasiatheria, Afrotheria, and Xenarthra, have been major issues in the recent discussion of basal relationships among placental mammals. However, despite considerable efforts these relationships, crucial to the understanding of eutherian evolution and biogeography, have remained essentially unresolved. Euarchontoglires and Laurasiatheria are generally joined into a common clade (Boreoeutheria), whereas the position of Afrotheria and Xenarthra relative to Boreoeutheria has been equivocal in spite of the use of comprehensive amounts of nuclear encoded sequences or the application of genome-level characters such as retroposons. The probable reason for this uncertainty is that the divergences took place long time ago and within a narrow temporal window, leaving only short common branches. With the aim of further examining basal eutherian relationships, we have collected conserved protein-coding sequences from 11 placental mammals, a marsupial and a bird, whose nuclear genomes have been largely sequenced. The length of the alignment of homologous sequences representing each individual species is 2,168,859 nt. This number of sites, representing 2840 protein-coding genes, exceeds by a considerable margin that of any previous study. The phylogenetic analysis joined Xenarthra and Afrotheria on a common branch, Atlantogenata. This topology was found to fit the data significantly better than the alternative trees.

  7. Common Moles, Atypical Moles (Dysplastic Nevi), and Risk of Melanoma

    MedlinePlus

    ... dysplastic nevus Having more than 50 common moles Sunlight : Sunlight is a source of UV radiation , which causes ... by spending time in the sun without protection. Sunlight can be reflected by sand, water, snow, ice, ...

  8. Modern Mathematics and the Mole.

    ERIC Educational Resources Information Center

    Henson, R.; Stumbles, A.

    1979-01-01

    Discusses several examples of the modern mathematics familiar to the pupils at the age where the mole concept is introduced, to help the teacher adopt an appropriate approach when dealing with this topic. (GA)

  9. Of Bushwahckers, Termites and Moles.

    ERIC Educational Resources Information Center

    Smelter, Richard W.

    2003-01-01

    Retired school administrator describes five types of school personnel that make an administrator's job difficult: Bushwackers, termites, CIA moles, rumor-mill addicts, and sartorial slobs. For example, termites are staff members who purposely volunteer for committees so they can sabotage the group's efforts from within. (PKP)

  10. Compartmentation of the cerebellar cortex: adaptation to lifestyle in the star-nosed mole Condylura cristata.

    PubMed

    Marzban, Hassan; Hoy, Nathan; Buchok, Matthew; Catania, Kenneth C; Hawkes, Richard

    2015-04-01

    The adult mammalian cerebellum is histologically uniform. However, concealed beneath the simple laminar architecture, it is organized rostrocaudally and mediolaterally into complex arrays of transverse zones and parasagittal stripes that is both highly reproducible between individuals and generally conserved across mammals and birds. Beyond this conservation, the general architecture appears to be adapted to the animal's way of life. To test this hypothesis, we have examined cerebellar compartmentation in the talpid star-nosed mole Condylura cristata. The star-nosed mole leads a subterranean life. It is largely blind and instead uses an array of fleshy appendages (the "star") to navigate and locate its prey. The hypothesis suggests that cerebellar architecture would be modified to reduce regions receiving visual input and expand those that receive trigeminal afferents from the star. Zebrin II and phospholipase Cß4 (PLCß4) immunocytochemistry was used to map the zone-and-stripe architecture of the cerebellum of the adult star-nosed mole. The general zone-and-stripe architecture characteristic of all mammals is present in the star-nosed mole. In the vermis, the four typical transverse zones are present, two with alternating zebrin II/PLCß4 stripes, two wholly zebrin II+/PLCß4-. However, the central and nodular zones (prominent visual receiving areas) are proportionally reduced in size and conversely, the trigeminal-receiving areas (the posterior zone of the vermis and crus I/II of the hemispheres) are uncharacteristically large. We therefore conclude that cerebellar architecture is generally conserved across the Mammalia but adapted to the specific lifestyle of the species.

  11. Tool to Distinguish Moles from Melanoma

    Cancer.gov

    Moles to Melanoma: Recognizing the ABCDE Features” presents photos that show changes in individual pigmented lesions over time, and describes the different appearances of moles, dysplastic nevi, and melanomas.

  12. Fossils and living taxa agree on patterns of body mass evolution: a case study with Afrotheria

    PubMed Central

    Puttick, Mark N.; Thomas, Gavin H.

    2015-01-01

    Most of life is extinct, so incorporating some fossil evidence into analyses of macroevolution is typically seen as necessary to understand the diversification of life and patterns of morphological evolution. Here we test the effects of inclusion of fossils in a study of the body size evolution of afrotherian mammals, a clade that includes the elephants, sea cows and elephant shrews. We find that the inclusion of fossil tips has little impact on analyses of body mass evolution; from a small ancestral size (approx. 100 g), there is a shift in rate and an increase in mass leading to the larger-bodied Paenungulata and Tubulidentata, regardless of whether fossils are included or excluded from analyses. For Afrotheria, the inclusion of fossils and morphological character data affect phylogenetic topology, but these differences have little impact upon patterns of body mass evolution and these body mass evolutionary patterns are consistent with the fossil record. The largest differences between our analyses result from the evolutionary model, not the addition of fossils. For some clades, extant-only analyses may be reliable to reconstruct body mass evolution, but the addition of fossils and careful model selection is likely to increase confidence and accuracy of reconstructed macroevolutionary patterns. PMID:26674947

  13. Fossils and living taxa agree on patterns of body mass evolution: a case study with Afrotheria.

    PubMed

    Puttick, Mark N; Thomas, Gavin H

    2015-12-22

    Most of life is extinct, so incorporating some fossil evidence into analyses of macroevolution is typically seen as necessary to understand the diversification of life and patterns of morphological evolution. Here we test the effects of inclusion of fossils in a study of the body size evolution of afrotherian mammals, a clade that includes the elephants, sea cows and elephant shrews. We find that the inclusion of fossil tips has little impact on analyses of body mass evolution; from a small ancestral size (approx. 100 g), there is a shift in rate and an increase in mass leading to the larger-bodied Paenungulata and Tubulidentata, regardless of whether fossils are included or excluded from analyses. For Afrotheria, the inclusion of fossils and morphological character data affect phylogenetic topology, but these differences have little impact upon patterns of body mass evolution and these body mass evolutionary patterns are consistent with the fossil record. The largest differences between our analyses result from the evolutionary model, not the addition of fossils. For some clades, extant-only analyses may be reliable to reconstruct body mass evolution, but the addition of fossils and careful model selection is likely to increase confidence and accuracy of reconstructed macroevolutionary patterns.

  14. High inter-individual variation in the gestation length of the hedgehog tenrec, Echinops telfairi (Afrotheria).

    PubMed

    Künzle, H; Poulsen Nautrup, C; Schwarzenberger, F

    2007-02-01

    The gestation length (GL) of Tenrecs (Tenrecinae, Afrotheria) is still uncertain. This lack of knowledge also applies to the lesser hedgehog tenrec, Echinops telfairi, the species most commonly bred and maintained in captivity. The animals used in this study were held under controlled conditions (light, temperature and humidity). In order to determine the GL, groups of female tenrecs were subjected to various mating procedures followed by isolation periods of different lengths. A total of n=249 pregnancies were analysed and the number of offspring per litter was 3.29+/-0.09. The length of gestation could be determined in n=199 pregnancies and a mean GL of 67.53+/-0.36 days was calculated. Initial attempts with isolation periods of less than 16 days did not allow to accurately define the GL. Experiments with longer isolation periods and females subjected to only one mating procedure (n=10) revealed a variation in the GLs of 57-79 days. However, in one female a GL of only 50 days was also observed indicating an even greater range in GL variation. There was a statistically significant tendency for shorter GLs in the animals that conceived later in the mating season, but no statistical evidence was found that age, parity or litter size played an essential role in determining the GL. In conclusion, an unexpected high variability in gestation length in E. telfairi was demonstrated although the study animals were kept under controlled environmental conditions. The factors and mechanisms regulating this high intra-species variability in gestation length need further investigations.

  15. Neocortical neuron types in Xenarthra and Afrotheria: implications for brain evolution in mammals.

    PubMed

    Sherwood, Chet C; Stimpson, Cheryl D; Butti, Camilla; Bonar, Christopher J; Newton, Alisa L; Allman, John M; Hof, Patrick R

    2009-02-01

    Interpreting the evolution of neuronal types in the cerebral cortex of mammals requires information from a diversity of species. However, there is currently a paucity of data from the Xenarthra and Afrotheria, two major phylogenetic groups that diverged close to the base of the eutherian mammal adaptive radiation. In this study, we used immunohistochemistry to examine the distribution and morphology of neocortical neurons stained for nonphosphorylated neurofilament protein, calbindin, calretinin, parvalbumin, and neuropeptide Y in three xenarthran species-the giant anteater (Myrmecophaga tridactyla), the lesser anteater (Tamandua tetradactyla), and the two-toed sloth (Choloepus didactylus)-and two afrotherian species-the rock hyrax (Procavia capensis) and the black and rufous giant elephant shrew (Rhynchocyon petersi). We also studied the distribution and morphology of astrocytes using glial fibrillary acidic protein as a marker. In all of these species, nonphosphorylated neurofilament protein-immunoreactive neurons predominated in layer V. These neurons exhibited diverse morphologies with regional variation. Specifically, high proportions of atypical neurofilament-enriched neuron classes were observed, including extraverted neurons, inverted pyramidal neurons, fusiform neurons, and other multipolar types. In addition, many projection neurons in layers II-III were found to contain calbindin. Among interneurons, parvalbumin- and calbindin-expressing cells were generally denser compared to calretinin-immunoreactive cells. We traced the evolution of certain cortical architectural traits using phylogenetic analysis. Based on our reconstruction of character evolution, we found that the living xenarthrans and afrotherians show many similarities to the stem eutherian mammal, whereas other eutherian lineages display a greater number of derived traits.

  16. Mold, Mould, Mole-d: The Three M's of Career Development

    ERIC Educational Resources Information Center

    Amundson, Norman E.

    2008-01-01

    The author explores a creative idea development process wherein one begins by applying the image of "breaking the mold" to career development and then extending the process further by considering other related images. In this article, the related images include synonyms for mold such as mould and mole-d (the mole is a small burrowing animal with…

  17. Avogadro Number and Mole: A Royal Confusion.

    ERIC Educational Resources Information Center

    Emiliani, Cesare

    1991-01-01

    There is a great deal of confusion in physics and chemistry textbooks, dictionaries, manuals, and handbooks about the definition of Avogadro's number and the term "mole." Avogadro's number is defined simply as the number of atomic mass units in one gram. Mole is defined as the mass of one Avogadro number of identical items. (Author/PR)

  18. Jaw anatomy of Potamogale velox (Tenrecidae, Afrotheria) with a focus on cranial arteries and the coronoid canal in mammals

    PubMed Central

    Brocklehurst, Robert J.; Crumpton, Nick; Button, Evie

    2016-01-01

    Afrotheria is a strongly supported clade within placental mammals, but morphological synapomorphies for the entire group have only recently come to light. Soft tissue characters represent an underutilized source of data for phylogenetic analysis, but nonetheless provide features shared by some or all members of Afrotheria. Here, we investigate the developmental anatomy of Potamogale velox (Tenrecidae) with histological and computerized tomographic data at different ontogenetic ages, combined with osteological data from other mammals, to investigate patterns of cranial arterial supply and the distribution of the coronoid canal. Potamogale is atypical among placental mammals in exhibiting a small superior stapedial artery, a primary supply of the posterior auricular by the posterior stapedial artery, and the development of vascular plexuses (possibly with relevance for heat exchange) in the posterior and dorsal regions of its neck. In addition, the posterior aspect of Meckel’s cartilage increases its medial deflection in larger embryonic specimens as the mandibular condyle extends mediolaterally during embryogenesis. We also map the distribution of the coronoid canal across mammals, and discuss potential confusion of this feature with alveoli of the posterior teeth. The widespread distribution of the coronoid canal among living and fossil proboscideans, sirenians, and hyracoids supports previous interpretations that a patent coronoid canal is a synapomorphy of paenungulates, but not afrotherians as a whole. PMID:27114870

  19. Genetics Home Reference: recurrent hydatidiform mole

    MedlinePlus

    ... hydatidiform mole occurs early in pregnancy when an embryo does not fully develop and the placenta develops ... that they will be inactive in the developing embryo; the corresponding paternal genes are active. NLRP7 or ...

  20. Measurement Corner Mass, Moles and Avogadro's Number

    ERIC Educational Resources Information Center

    Todd, Robert M.

    1977-01-01

    Discusses and clarifies the confusion arising from the use of the terms "mass,""volume,""matter,""mole," and "Avogadro's number." Suggests three laboratory activities concerning mass, volume, and number of particles in a given volume. (CS)

  1. Moles and Mole Control on British Farms, Amenities and Gardens after Strychnine Withdrawal

    PubMed Central

    Baker, Sandra E.; Ellwood, Stephen A.; Johnson, Paul J.; Macdonald, David W.

    2016-01-01

    Simple Summary Moles are burrowing mammals that are regarded as pests in Britain, and until 2006 they could legally be killed using strychnine poison. When strychnine was withdrawn there were fears that mole populations would increase. We surveyed farmers, amenity managers and householders about moles and mole control on their land in 2007, post strychnine withdrawal. Kill-trapping was by far the preferred control method used and control may be used more than can be justified by damage levels or the effect of control on damage. Mole traps are unregulated, unlike most other spring traps, and some might not meet current welfare standards. We found no evidence that mole activity had increased since a 1992 survey of farms. Abstract Moles are considered pests in Britain, but this issue has been little studied. Lower welfare standards have been tolerated for moles than for most other managed wild mammal species, as use of both the controversial poison, strychnine, and unregulated traps have been permitted. Strychnine was withdrawn in 2006 and there were fears that mole populations would increase as a result. In 2007, we conducted a comprehensive, nationwide survey of land manager perceptions, opinions and behaviour regarding moles and mole control on farms, amenities and domestic gardens in Britain. We surveyed 2150 land managers (achieving a 59% response rate) and ground-truthed 29 responses. Moles were reported to be present on most farms and amenities, and 13% of gardens, and were more common in lighter soils. Where present, moles were usually considered pests, this being more likely in Wales, Scotland and northern England, on livestock and mixed farms, and on large, high-value amenities, e.g., racecourses and golf courses. Mole control followed similar patterns to mole presence. More control may occur than is economically, and therefore potentially ethically, justified. Control should be more carefully considered and, where necessary, more effectively targeted. Kill

  2. Moles and Mole Control on British Farms, Amenities and Gardens after Strychnine Withdrawal.

    PubMed

    Baker, Sandra E; Ellwood, Stephen A; Johnson, Paul J; Macdonald, David W

    2016-06-08

    Moles are considered pests in Britain, but this issue has been little studied. Lower welfare standards have been tolerated for moles than for most other managed wild mammal species, as use of both the controversial poison, strychnine, and unregulated traps have been permitted. Strychnine was withdrawn in 2006 and there were fears that mole populations would increase as a result. In 2007, we conducted a comprehensive, nationwide survey of land manager perceptions, opinions and behaviour regarding moles and mole control on farms, amenities and domestic gardens in Britain. We surveyed 2150 land managers (achieving a 59% response rate) and ground-truthed 29 responses. Moles were reported to be present on most farms and amenities, and 13% of gardens, and were more common in lighter soils. Where present, moles were usually considered pests, this being more likely in Wales, Scotland and northern England, on livestock and mixed farms, and on large, high-value amenities, e.g., racecourses and golf courses. Mole control followed similar patterns to mole presence. More control may occur than is economically, and therefore potentially ethically, justified. Control should be more carefully considered and, where necessary, more effectively targeted. Kill-trapping was the favoured recent and future method on farms and amenities, even if strychnine was to be reintroduced; however, because mole traps are currently unregulated, some might not meet current welfare standards if tested. We found no evidence for an increase in moles since a farm questionnaire survey conducted in 1992; this could have wider implications for future wildlife management policy changes.

  3. The Origin of the Mole Concept

    ERIC Educational Resources Information Center

    Jensen, William B.

    2004-01-01

    German Chemist, August Wilhelm Hofmann first introduced the term "molar" (from the Latin moles, meaning "a large mass") into chemistry, around 1865. The particular use of the term molar gained currency in the physics literature, where it was in common use at least through the 1940s.

  4. Relating the Mole Concept and Fundamental Mathematics.

    ERIC Educational Resources Information Center

    Phillips, Kenneth L.

    The high percentage of students who have difficulty in solving free-response problems related to the mole concept was addressed by implementation of reading skill strategies and computer assisted instruction. Frayer models, semantic mapping, and graphic organizers from Reading in the Content Area (RICA) were used to increase student understanding…

  5. Prolactin in the Afrotheria: characterization of genes encoding prolactin in elephant (Loxodonta africana), hyrax (Procavia capensis) and tenrec (Echinops telfairi).

    PubMed

    Wallis, Michael

    2009-02-01

    Pituitary prolactin shows an episodic pattern of molecular evolution, with occasional short bursts of rapid change imposed on a generally rather slow evolutionary rate. In mammals, episodes of rapid change occurred in the evolution of primates, cetartiodactyls, rodents and the elephant. The bursts of rapid evolution in cetartiodactyls and rodents were followed by duplications of the prolactin gene that gave rise to large families of prolactin-related proteins including placental lactogens, while in primates the burst was followed by corresponding duplications of the related GH gene. The position in elephant is less clear. Extensive data relating to the genomic sequences of elephant and two additional members of the group Afrotheria are now available, and have been used here to characterize the prolactin genes in these species and explore whether additional prolactin-related genes are present. The results confirm the rapid evolution of elephant (Loxodonta africana) prolactin - the sequence of elephant prolactin is substantially different from that predicted for the ancestral placental mammal. Hyrax (Procavia capensis) prolactin is even more divergent but tenrec (Echinops telfairi) prolactin is strongly conserved. No evidence was obtained from searches of public databases for additional genes encoding prolactin-like proteins in any of these species. Detailed analysis of evolutionary rates, and other factors, indicates that the episode of rapid change in hyrax, and probably elephant, was adaptive, though the nature of the associated biological change(s) is not clear.

  6. LINE-1 distribution in Afrotheria and Xenarthra: implications for understanding the evolution of LINE-1 in eutherian genomes.

    PubMed

    Waters, Paul D; Dobigny, Gauthier; Pardini, Amanda T; Robinson, Terence J

    2004-09-01

    Long interspersed nuclear elements (LINEs) comprise about 21% of the human genome (of which L1 is most abundant) and are preferentially accumulated in AT-rich regions, as well as the X and Y chromosomes. Most knowledge of L1 distribution in mammals is restricted to human and mouse. Here we report the first investigation of L1 distribution in the genomes of a wide variety of eutherian mammals, including species in the two basal clades, Afrotheria and Xenarthra. Our results show L1 accumulation on the X of all eutherian mammals, an observation consistent with an ancestral involvement of these elements in the X-inactivation process (the Lyon repeat hypothesis). Surprisingly, conspicuous accumulation of L1 in AT-rich regions of the genome was not observed in any species outside of Euarchontoglires (represented by human, mouse and rabbit). Although several features were common to most species investigated, our comprehensive survey shows that the patterns observed in human and mouse are, in many aspects, far from typical for all mammals. We discuss these findings with reference to models that have previously been proposed to explain the AT distribution bias of L1 in human and mouse, and how this relates to the evolution of these elements in other eutherian genomes.

  7. Social Structure Predicts Genital Morphology in African Mole-Rats

    PubMed Central

    Seney, Marianne L.; Kelly, Diane A.; Goldman, Bruce D.; Šumbera, Radim; Forger, Nancy G.

    2009-01-01

    Background African mole-rats (Bathyergidae, Rodentia) exhibit a wide range of social structures, from solitary to eusocial. We previously found a lack of sex differences in the external genitalia and morphology of the perineal muscles associated with the phallus in the eusocial naked mole-rat. This was quite surprising, as the external genitalia and perineal muscles are sexually dimorphic in all other mammals examined. We hypothesized that the lack of sex differences in naked mole-rats might be related to their unusual social structure. Methodology/Principal Findings We compared the genitalia and perineal muscles in three African mole-rat species: the naked mole-rat, the solitary silvery mole-rat, and the Damaraland mole-rat, a species considered to be eusocial, but with less reproductive skew than naked mole-rats. Our findings support a relationship between social structure, mating system, and sexual differentiation. Naked mole-rats lack sex differences in genitalia and perineal morphology, silvery mole-rats exhibit sex differences, and Damaraland mole-rats are intermediate. Conclusions/Significance The lack of sex differences in naked mole-rats is not an attribute of all African mole-rats, but appears to have evolved in relation to their unusual social structure and reproductive biology. PMID:19829697

  8. Can they dig it? Functional morphology and semifossoriality among small-eared shrews, genus Cryptotis (Mammalia, Soricidae)

    USGS Publications Warehouse

    Woodman, Neal; Gaffney, Sarah A.

    2014-01-01

    Small-eared shrews (Mammalia: Soricidae: Cryptotis), exhibit modifications of the forelimb skeleton that have been interpreted as adaptations for semifossoriality. Most species inhabit remote regions, however, and their locomotory and foraging behaviors remain mostly speculative. To better understand the morphological modifications in the absence of direct observations, we quantified variation in these species by measuring 151 individuals representing 18 species and populations of Cryptotis and two species of moles (Talpidae) for comparison. From our measurements, we calculated 22 indices, most of which have been used previously to characterize substrate use among rodents and other taxa. We analyzed the indices using 1) average percentile ranks, 2) principal components analysis, and 3) cluster analysis. From these analyses, we determined that three basic modes of substrate adaptation are present within Cryptotis: 1) a primarily terrestrial mode, with species that are capable of burrowing, but lack adaptations to increase digging efficiency, 2) a semifossorial mode, with species whose forelimbs bones show strong muscle attachment areas and increased mechanical advantage, and 3) an intermediate mode. In addition to identifying new morphological characters and contributing to our understanding of the functional morphology of soricids, these analyses provide additional insight into the ecology of the species of interest.

  9. Can they dig it? Functional morphology and semifossoriality among small-eared shrews, genus Cryptotis (Mammalia, Soricidae).

    PubMed

    Woodman, Neal; Gaffney, Sarah A

    2014-07-01

    Small-eared shrews (Mammalia: Soricidae: Cryptotis), exhibit modifications of the forelimb skeleton that have been interpreted as adaptations for semifossoriality. Most species inhabit remote regions, however, and their locomotory and foraging behaviors remain mostly speculative. To better understand the morphological modifications in the absence of direct observations, we quantified variation in these species by measuring 151 individuals representing 18 species and populations of Cryptotis and two species of moles (Talpidae) for comparison. From our measurements, we calculated 22 indices, most of which have been used previously to characterize substrate use among rodents and other taxa. We analyzed the indices using 1) average percentile ranks, 2) principal components analysis, and 3) cluster analysis. From these analyses, we determined that three basic modes of substrate adaptation are present within Cryptotis: 1) a primarily terrestrial mode, with species that are capable of burrowing, but lack adaptations to increase digging efficiency, 2) a semifossorial mode, with species whose forelimbs bones show strong muscle attachment areas and increased mechanical advantage, and 3) an intermediate mode. In addition to identifying new morphological characters and contributing to our understanding of the functional morphology of soricids, these analyses provide additional insight into the ecology of the species of interest.

  10. Insights: A LAP on Moles: Teaching an Important Concept.

    ERIC Educational Resources Information Center

    Ihde, John

    1985-01-01

    Describes a learning activity packet (LAP) designed to help students understand the basic concept of the mole as a chemical unit; know relationships between the mole and atomic weights in the periodic table; and solve basic conversion problems involving moles, atoms, and molecules. (JN)

  11. Instrumented Moles for Planetary Subsurface Regolith Studies

    NASA Astrophysics Data System (ADS)

    Richter, L. O.; Coste, P. A.; Grzesik, A.; Knollenberg, J.; Magnani, P.; Nadalini, R.; Re, E.; Romstedt, J.; Sohl, F.; Spohn, T.

    2006-12-01

    Soil-like materials, or regolith, on solar system objects provide a record of physical and/or chemical weathering processes on the object in question and as such possess significant scientific relevance for study by landed planetary missions. In the case of Mars, a complex interplay has been at work between impact gardening, aeolian as well as possibly fluvial processes. This resulted in regolith that is texturally as well as compositionally layered as hinted at by results from the Mars Exploration Rover (MER) missions which are capable of accessing shallow subsurface soils by wheel trenching. Significant subsurface soil access on Mars, i.e. to depths of a meter or more, remains to be accomplished on future missions. This has been one of the objectives of the unsuccessful Beagle 2 landed element of the ESA Mars Express mission having been equipped with the Planetary Underground Tool (PLUTO) subsurface soil sampling Mole system capable of self-penetration into regolith due to an internal electro-mechanical hammering mechanism. This lightweight device of less than 900 g mass was designed to repeatedly obtain and deliver to the lander regolith samples from depths down to 2 m which would have been analysed for organic matter and, specifically, organic carbon from potential extinct microbial activity. With funding from the ESA technology programme, an evolved Mole system - the Instrumented Mole System (IMS) - has now been developed to a readiness level of TRL 6. The IMS is to serve as a carrier for in situ instruments for measurements in planetary subsurface soils. This could complement or even eliminate the need to recover samples to the surface. The Engineering Model hardware having been developed within this effort is designed for accommodating a geophysical instrument package (Heat Flow and Physical Properties Package, HP3) that would be capable of measuring regolith physical properties and planetary heat flow. The chosen design encompasses a two-body Mole

  12. Mole guns in Turkey in 2003-2005.

    PubMed

    Yilmaz, Riza; Birincioğlu, Ismail; Cakir, Ismail; Uner, H Bülent; Açikgöz, Dinç; Seçkin, Cetin

    2007-01-01

    This study describes the frequency of mole guns in Turkey by examining the cases sent to the Council of Forensic Medicine of Turkey between 2003 and 2005. In total, 11 mole guns were examined. Mole guns are manufactured to be used as a trap against detrimental animals. Although they are not meant to be used as a firearm, they are able to cause death. Mole guns appearing in regular casework were evaluated in terms of type of the gun, number of barrels, size and caliber, rifling, design, mechanism, fitness for use, legality, and geographical distribution. Ninety-one percent of the guns were 12 gauge. Most commonly they originate from Inner Anatolia. Mole guns are typically handmade. Some examples of injuries and deaths caused by mole guns are also offered.

  13. Entomopathogenic fungi detection and avoidance by mole crickets (Orthoptera: Gryllotalpidae).

    PubMed

    Thompson, Sarah R; Brandenburg, Rick L; Roberson, Gary T

    2007-02-01

    A chamber to monitor mole cricket behavior was designed using two different soil-filled containers and photosensors constructed from infrared emitters and detectors. Mole crickets (Scapteriscus spp.) were introduced into a center tube that allowed them to choose whether to enter and tunnel in untreated soil or soil treated with Beauveria bassiana (Balsamo) Vuillemin. Each time the cricket passed through the photosensor located near the entrance of soil-filled containers, the infrared light was blocked and the exact moment that this occurred was logged onto a computer using custom-written software. Data examined included the first photosensor trigger, total number of sensor triggers, presence of tunneling, and final location of the cricket after 18 h. These behaviors were analyzed to discern differences in mole cricket behavior in the presence of different treatments and to elucidate the mechanism that mole crickets use to detect fungal pathogens. The first study examined substrate selection and tunneling behavior of the southern mole cricket, Scapteriscus borellii Giglio-Tos, to the presence of five strains of B. bassiana relative to a control. There were no differences between the first sensor trigger and total number of triggers, indicating the mole crickets are not capable of detecting B. bassiana at a distance of 8 cm. Changes in mole cricket tunneling and residence time in treated soil occurred for some strains of B. bassiana but not others. One of the strains associated with behavioral changes in the southern mole cricket was used in a second experiment testing behavioral responses of the tawny mole cricket, S. vicinus Scudder. In addition to the formulated product of this strain, the two separate components of that product (conidia and carrier) and bifenthrin, an insecticide commonly used to control mole crickets, were tested. There were no differences in mole cricket behavior between treatments in this study. The differences in behavioral responses between

  14. The evolution of the thyroid hormone distributor protein transthyretin in the order insectivora, class mammalia.

    PubMed

    Prapunpoj, P; Richardson, S J; Fumagalli, L; Schreiber, G

    2000-08-01

    Thyroid hormones are involved in the regulation of growth and metabolism in all vertebrates. Transthyretin is one of the extracellular proteins with high affinity for thyroid hormones which determine the partitioning of these hormones between extracellular compartments and intracellular lipids. During vertebrate evolution, both the tissue pattern of expression and the structure of the gene for transthyretin underwent characteristic changes. The purpose of this study was to characterize the position of Insectivora in the evolution of transthyretin in eutherians, a subclass of Mammalia. Transthyretin was identified by thyroxine binding and Western analysis in the blood of adult shrews, hedgehogs, and moles. Transthyretin is synthesized in the liver and secreted into the bloodstream, similar to the situation for other adult eutherians, birds, and diprotodont marsupials, but different from that for adult fish, amphibians, reptiles, monotremes, and Australian polyprotodont marsupials. For the characterization of the structure of the gene and the processing of mRNA for transthyretin, cDNA libraries were prepared from RNA from hedgehog and shrew livers, and full-length cDNA clones were isolated and sequenced. Sections of genomic DNA in the regions coding for the splice sites between exons 1 and 2 were synthesized by polymerase chain reaction and sequenced. The location of splicing was deduced from comparison of genomic with cDNA nucleotide sequences. Changes in the nucleotide sequence of the transthyretin gene during evolution are most pronounced in the region coding for the N-terminal region of the protein. Both the derived overall amino sequences and the N-terminal regions of the transthyretins in Insectivora were found to be very similar to those in other eutherians but differed from those found in marsupials, birds, reptiles, amphibians, and fish. Also, the pattern of transthyretin precursor mRNA splicing in Insectivora was more similar to that in other eutherians

  15. For Mole Problems, Call Avogadro: 602-1023.

    ERIC Educational Resources Information Center

    Uthe, R. E.

    2002-01-01

    Describes techniques to help introductory students become familiar with Avogadro's number and mole calculations. Techniques involve estimating numbers of common objects then calculating the length of time needed to count large numbers of them. For example, the immense amount of time required to count a mole of sand grains at one grain per second…

  16. Geochemical mole-balance modeling with uncertain data

    USGS Publications Warehouse

    Parkhurst, D.L.

    1997-01-01

    Geochemical mole-balance models are sets of chemical reactions that quantitatively account for changes in the chemical and isotopic composition of water along a flow path. A revised mole-balance formulation that includes an uncertainty term for each chemical and isotopic datum is derived. The revised formulation is comprised of mole-balance equations for each element or element redox state, alkalinity, electrons, solvent water, and each isotope; a charge-balance equation and an equation that relates the uncertainty terms for pH, alkalinity, and total dissolved inorganic carbon for each aqueous solution: inequality constraints on the size of the uncertainty terms: and inequality constraints on the sign of the mole transfer of reactants. The equations and inequality constraints are solved by a modification of the simplex algorithm combined with an exhaustive search for unique combinations of aqueous solutions and reactants for which the equations and inequality constraints can be solved and the uncertainty terms minimized. Additional algorithms find only the simplest mole-balance models and determine the ranges of mixing fractions for each solution and mole transfers for each reactant that are consistent with specified limits on the uncertainty terms. The revised formulation produces simpler and more robust mole-balance models and allows the significance of mixing fractions and mole transfers to be evaluated. In an example from the central Oklahoma aquifer, inclusion of up to 5% uncertainty in the chemical data can reduce the number of reactants in mole-balance models from seven or more to as few as three, these being cation exchange, dolomite dissolution, and silica precipitation. In another example from the Madison aquifer; inclusion of the charge-balance constraint requires significant increases in the mole transfers of calcite, dolomite, and organic matter, which reduce the estimated maximum carbon 14 age of the sample by about 10,000 years, from 22,700 years to

  17. Deaths caused by mole guns: three case reports.

    PubMed

    Demirci, Serafettin; Gunaydin, Gursel; Dogan, Kamil Hakan; Erkol, Zerrin

    2008-07-01

    Possession of firearms is limited because of the technological requirements in production and strict laws. However, anyone can manufacture a handmade firearm by following simple instructions and has no legal liability. A mole gun is an unusual weapon used to kill moles in agricultural areas. It propels pellets in a similar way as a shotgun. This study presents three cases of death caused by mole guns. Two of the cases were accidental, and the other case was suicidal. The first case involved a 51-year-old man who was checking the mole gun when it fired, injuring his left eye and the left region of his face. He died in the hospital after 3 days of medical treatment. The second case was a 78-year-old man, who had been intermittently treated for depression over the last 15 years. He died instantly after placing the mole gun vertically against his head and firing it. The third case was a 43-year-old man who had been trying to set up a mole gun device in his potato field when the weapon accidentally discharged. The victim was injured seriously and died in the hospital a short time later. In conclusion, because the mole gun may cause lethal wounds in humans when fired from a short distance, the researchers believe that its production and use should be in accordance with firearms laws.

  18. Results of the mole penetration tests in different materials

    NASA Astrophysics Data System (ADS)

    Wawrzaszek, Roman; Seweryn, Karol; Grygorczuk, Jerzy; Banaszkiewicz, Marek; Rybus, Tomasz; Wisniewski, Lukasz; Neal, Clive R.; Huang, Shaopeng

    2010-05-01

    Mole devices are low velocity, medium to high energy, self-driven penetrators, designed as a carrier of different sensors for in situ investigations of subsurface layers of planetary bodies. The maximum insertion depth of such devices is limited by energy of single mole's stroke and soil resistance for the dynamic penetration. A mole penetrator ‘KRET' has been designed, developed, and successfully tested at Space Research Centre PAS in Poland. The principle of operation of the mole bases on the interaction between three masses: the cylindrical casing, the hammer, and the rest of the mass, acting as a support mass. This approach takes advantage of the MUPUS penetrator (a payload of Philae lander on Rosetta mission) insertion tests knowledge. Main parameters of the mole KRET are listed below: - outer diameter: 20.4mm, - length: 330mm, - total mass: 488g, - energy of the driving spring: 2.2J, - average power consumption: 0.28W, - average insertion progress/stroke: 8.5mm, The present works of Space Research Center PAS team are focused on three different activities. First one includes investigations of the mole penetration effectiveness in the lunar analogues (supported by ESA PECS project). Second activity, supported by Polish national fund, is connected with numerical calculation of the heat flow investigations and designing and developing the Heat Flow Probe Hardware Component (HPHC) for L-GIP NASA project. It's worth noting that L-GIP project refers to ILN activity. Last activity focuses on preparing the second version of the mole ready to work in low thermal and pressure conditions. Progress of a mole penetrator in granular medium depends on the mechanical properties of this medium. The mole penetrator ‘KRET' was tested in different materials: dry quartz sand (0.3 - 0.8 grain size), wet quartz sand, wheat flour and lunar regolith mechanical simulant - Chemically Enhanced OB-1 (CHENOBI). Wheat flour was selected due to its high cohesion rate and small grain size

  19. Anatomy of mole external genitalia: Setting the record straight.

    PubMed

    Sinclair, Adriane Watkins; Glickman, Stephen E; Baskin, Laurence; Cunha, Gerald R

    2016-03-01

    Anatomy of male and female external genitalia of adult mice (Mus musculus) and broad-footed moles (Scapanus latimanus) was re-examined to provide more meaningful anatomical terminology. In the past the perineal appendage of male broad-footed moles has been called the penis, while the female perineal appendage has been given several terms (e.g. clitoris, penile clitoris, peniform clitoris and others). Histological examination demonstrates that perineal appendages of male and female broad-footed moles are the prepuce, which in both sexes are covered externally with a hair-bearing epidermis and lacks erectile bodies. The inner preputial epithelium is non-hair-bearing and defines the preputial space in both sexes. The penis of broad-footed moles lies deep within the preputial space, is an "internal organ" in the resting state and contains the penile urethra, os penis, and erectile bodies. The clitoris of broad-footed moles is defined by a U-shaped clitoral epithelial lamina. Residing within clitoral stroma encompassed by the clitoral epithelial lamina is the corpus cavernosum, blood-filled spaces and the urethra. External genitalia of male and female mice are anatomically similar to that of broad-footed moles with the exception that in female mice the clitoris contains a small os clitoridis and lacks defined erectile bodies, while male mice have an os penis and a prominent distal cartilaginous structure within the male urogenital mating protuberance (MUMP). Clitori of female broad-footed moles lack an os clitoridis but contain defined erectile bodies, while male moles have an os penis similar to the mouse but lack the distal cartilaginous structure.

  20. Amount of substance and the proposed redefinition of the mole

    NASA Astrophysics Data System (ADS)

    Milton, M. J. T.; Mills, I. M.

    2009-06-01

    There has been considerable discussion about the merits of redefining four of the base units of the SI, including the mole. In this paper, the options for implementing a new definition for the mole based on a fixed value for the Avogadro constant are discussed. They are placed in the context of the macroscopic nature of the quantity amount of substance and the opportunity to introduce a system for molar and atomic masses with unchanged values and consistent relative uncertainties.

  1. Unusual Presentation of Invasive Mole: A Case Report

    PubMed Central

    Aminimoghaddam, Soheila; Maghsoudnia, Andisheh

    2017-01-01

    Background: Invasive mole is responsible for most cases of localized gestational trophoblastic neoplasia. Gestational trophoblastic disease describes a number of gynecologic tumors that originate in trophoblastic layer including hydatidiform mole (complete or partial), invasive mole, choriocarcinoma, placental site trophoblastic tumor and epitheloid trophoblastic tumor. Invasive mole may arise from any pregnancy event although in most cases is diagnosed after molar pregnancy. Overall cure rate in low risk patients is nearly 100% and in high-risk patient 90%. In rare cases, molar tissue traverses thickness of myometrium and leads to perforation and acute abdomen and invasive mole infrequently metastasis. The best treatment option is chemotherapy (according to stage and score with single or multiple agent) and in patients that fertility is not the matter, hysterectomy can be done. Case Presentation: A 41 years old G3P2ab1 woman referred to Firouzgar hospital 2 months after curettage of molar pregnancy with vaginal bleeding and acute abdomen. In workup, HCG 224000 mIU/ml and evidence of metastasis was detected. Chemotherapy due to stage 3 and score 9 and surgery due to acute abdomen was done. This case was reported for its rarity. Discussion: This case reported about ovarian metastasis and uterine rupture with acute abdomen and involvement of omentum in metastatic invasive mole. Lack of surveillance led to extensive morbidity. Management of this patient was successful. In follow up, she was free of disease without sequel of any kind for five years now. PMID:28377901

  2. Genetic variants of Cao Bang hantavirus in the Chinese mole shrew (Anourosorex squamipes) and Taiwanese mole shrew (Anourosorex yamashinai).

    PubMed

    Gu, Se Hun; Arai, Satoru; Yu, Hon-Tsen; Lim, Burton K; Kang, Hae Ji; Yanagihara, Richard

    2016-06-01

    To determine the genetic diversity and geographic distribution of Cao Bang virus (CBNV) and to ascertain the existence of CBNV-related hantaviruses, natural history collections of archival tissues from Chinese mole shrews (Anourosorex squamipes) and Taiwanese mole shrews (Anourosorex yamashinai), captured in Guizho Province, People's Republic of China, and in Nantou County, Taiwan, in 2006 and 1989, respectively, were analyzed for hantavirus RNA by RT-PCR. Pair-wise alignment and comparison of the S-, M- and L-segment sequences indicated CBNV in two of five Chinese mole shrews and a previously unrecognized hantavirus, named Xinyi virus (XYIV), in seven of 15 Taiwanese mole shrews. XYIV was closely related to CBNV in Vietnam and China, as well as to Lianghe virus (LHEV), recently reported as a distinct hantavirus species in Chinese mole shrews from Yunnan Province in China. Phylogenetic analyses, using maximum-likelihood and Bayesian methods, showed that XYIV shared a common ancestry with CBNV and LHEV, in keeping with the evolutionary relationship between Anourosorex mole shrews. Until such time that tissue culture isolates of CBNV, LHEV and XYIV can be fully analyzed, XYIV and LHEV should be regarded as genetic variants, or genotypes, of CBNV.

  3. A case of true tubal hydatidiform mole and literature review.

    PubMed

    Siozos, A; Sriemevan, A

    2010-08-09

    Tubal hydatidiform mole is an uncommon condition with about 40 confirmed cases in the accessible literature. The patient usually presents with symptoms and signs of a classical ectopic pregnancy and it is only after histological examination and DNA ploidy analysis of the conceptus that a hydatidiform mole is diagnosed. Management requires complete removal of the conceptus and follow-up needs to be arranged with an appropriate supraregional centre. The authors present a case of complete molar tubal pregnancy and a review of the literature.

  4. The mole, amount of substance and primary methods

    NASA Astrophysics Data System (ADS)

    Milton, Martin J. T.

    2013-04-01

    This paper is an introduction to the principles developed for the application of metrology to the field of chemistry and particularly to analytical chemistry. It starts with a discussion of the mole, the base unit of the SI that is most relevant to analytical chemistry. The mole has become the subject of particular discussion recently, since the publication of proposals to re-define it along with three other base units of the SI. This discussion has also generated interest in the origin of the term ‘amount of substance’ used as the quantity for which the mole is the unit. This paper reviews the origin of this term and explains why it is not sufficient to replace it with an alternative such as a ‘number of entities’. The paper concludes with some discussion of how the mole is realized through the use of primary methods of measurement. This paper is based on a lecture given at the International School of Physics ‘Enrico Fermi’, Course CLXXXV: Metrology and Physical Constants,held in Varenna on 17-27 July 2012. It will also be published in the proceedings of the school, edited by E Bava, M Kühne and A M Rossi (IOS Press, Amsterdam and SIF, Bologna).

  5. Hydatidiform mole presentation as a tubal ectopic pregnancy.

    PubMed

    Nakeer, Tabassum; Shahid, Muhammad; Ansari, Muhammad Asad; Nakeer, Rooham

    2014-05-01

    Presentation of hydatidiform mole as tubal ectopic pregnancy is very rare. These patients usually present with ectopic pregnancy and are later diagnosed with hydatidiform mole on the basis of histological examination following surgery. We present the case of a 32-year-old female who presented with abdominal pain and vaginal bleed since 2 days of presentation. She was vitally stable. There was mild tenderness in hypogastrium and left iliac fossa. Pelvic examination showed mild bleeding per vaginum and fullness in both fornices. The patient was suspected of having an ectopic pregnancy. Ultrasonography of pelvis revealed fluid in cul-de-sac and a sac like mass of 1.8 cm attached to the left ovary. On laparotomy, there was a left sided tubal ectopic pregnancy and subsequently left salpingectomy was done. Histopathology of the tissue sample showed features of partial hydatidiform mole. Ectopic pregnancy can present as hydatidiform mole in rare cases for which histological examination of the tissue is required to establish the diagnosis.

  6. The complete mitogenome of Chinese Mole Shrew, Anourosorex squamipes (Soricidae).

    PubMed

    Li, Qun; Wang, Qiong; Chen, Guiying; Fu, Changkun; Chen, Shunde

    2016-01-01

    The Chinese Mole Shrew, Anourosorex squamipes belongs to the family Soricidae, and widely distributes in central and southern China, northern and south Burma, east India, northern Vietnam and Thailand. In this study, the complete mitochondrial genome sequence of Anourosorex squamipes was determined. The mitogenome is 17,121 base pairs in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 1 control region, with base composition of 34.0% A, 31.3% T, 22.0% C, and 12.7% G. The genome organization, nucleotide composition and codon usage did not differ significantly from those of other shrews. The study contributes to illuminating taxonomic status of Chinese Mole Shrew Anourosorex squamipes.

  7. Mole and Chemical Amount: A Discussion of the Fundamental Measurements of Chemistry.

    ERIC Educational Resources Information Center

    Gorin, George

    1994-01-01

    Teachers and students alike report difficulties with the measurement unit called mole. This article tries to demonstrate that mole and the corresponding quantity are not exceptional. Mole lacks the context of a given amount because the unit measures the relative number of atoms compared with those present in a standard. Discusses history of…

  8. Teaching the Mole Concept Using a Conceptual Change Method at College Level

    ERIC Educational Resources Information Center

    Uce, Musa

    2009-01-01

    Chemistry is a subject area that is difficult to understand for some students as it contains abstract concepts, such as mole, molecule and particle. The mole concept is one of the most important topics in which students have difficulty in understanding. There are many studies in the literature on the mole concept. Students who do not fully…

  9. Unpacking the Meaning of the Mole Concept for Secondary School Teachers and Students

    ERIC Educational Resources Information Center

    Fang, Su-Chi; Hart, Christina; Clarke, David

    2014-01-01

    The "mole" is a fundamental concept in quantitative chemistry, yet research has shown that the mole is one of the most perplexing concepts in the teaching and learning of chemistry. This paper provides a survey of the relevant literature, identifies the necessary components of a sound understanding of the mole concept, and unpacks and…

  10. A content analysis of the presentation of the mole concept in chemistry textbooks

    NASA Astrophysics Data System (ADS)

    Staver, John R.; Lumpe, Andrew T.

    The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the mole concept in high school and introductory college chemistry textbooks. The analysis was framed by four questions:1How is the mole defined?2What concepts about the atom are introduced prior to the mole?3Is Avogadro's constant presented as an experimentally determined value?4What is the context for introducing the mole?Twenty-nine high school and introductory college level chemistry texts were examined. After independent reading of appropriate sections of each text, discussion of differences, second or third readings of texts, and subsequent discussions, both authors reach 100% agreement concerning the results. Major conclusions were: Two ways of defining the mole dominate the texts. One way defines the mole as Avogadro's number (6.02 × 1023) particles; the other method defines the mole in terms of carbon-12. All texts that present a definition in terms of C-12 introduce and define concepts about the atom prior to introducing the mole. Most texts at all levels point out that the value 6.02 × 1023 is an experimentally determined quantity. Nearly all texts discuss the mole in relation to die problem of finding a way to count particles that are too small to be directly weighed. Most texts also use a familiar counting unit, such as the dozen, to introduce the mole by analogy. Four issues were discussed: (a) the defining attributes of the mole concept itself and the cognitive requirements for comprehending the two most frequently used definitions; (b) the connection between the definition of the mole presented in the text and the concepts about atoms that are introduced before the mole concept is developed; (c) the experimental nature of Avogadro's number; and (d) the context or setting for developing the mole concept.

  11. The distribution of doublecortin-immunopositive cells in the brains of four afrotherian mammals: the Hottentot golden mole (Amblysomus hottentotus), the rock hyrax (Procavia capensis), the eastern rock sengi (Elephantulus myurus) and the four-toed sengi (Petrodromus tetradactylus).

    PubMed

    Patzke, Nina; LeRoy, Andrea; Ngubane, Nhlanhla W; Bennett, Nigel C; Medger, Katarina; Gravett, Nadine; Kaswera-Kyamakya, Consolate; Gilissen, Emmanuel; Chawana, Richard; Manger, Paul R

    2014-01-01

    Adult neurogenesis in the mammalian brain is now a widely accepted phenomenon, typically occurring in two forebrain structures: the subgranular zone (SGZ) of the hippocampal dentate gyrus and the subventricular zone (SVZ). Until recently, the majority of studies have focused on laboratory rodents, and it is under debate whether the process of adult neurogenesis occurs outside of the SGZ and the SVZ in other mammalian species. In the present study, we investigated potential adult neurogenetic sites in the brains of two elephant shrews/sengis, a golden mole and a rock hyrax, all members of the superorder Afrotheria. Doublecortin (DCX) immunoreactivity was used as a proxy to visualise adult neurogenesis, which is expressed in neuronal precursor cells and immature neurons. In all four species, densely packed DCX-positive cells were present in the SVZ, from where cells appear to migrate along the rostral migratory stream towards the olfactory bulb (OB). DCX-immunopositive cells were present in the granular cell layer and the glomerular layer of the OB. In the hippocampus, DCX-immunopositive cells were observed in the SGZ and in the granular layer of the dentate gyrus, with DCX-immunopositive processes extending into the molecular layer. In addition to these well-established adult neurogenic regions, DCX-immunopositive cells were also observed in layer II of the neocortex and the piriform cortex. While the present study reveals a similar pattern of adult neurogenesis to that reported previously in other mammals, further studies are needed to clarify if the cortical DCX-immunopositive cells are newly generated neurons or cells undergoing cortical remodelling.

  12. Description of the mitogenome of Gansu mole (Scapanulus oweni).

    PubMed

    Xu, Yu; Huang, Xiaofeng; Hu, Yunting; Tu, Feiyun

    2016-05-01

    The Gansu mole Scapanulus oweni belongs to family Talpidae, and is distributed in the Central and Southwest China. In this study, the total mitochondrial genome of S. oweni was firstly determined. The genome is 16,826 bases in length and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and a displacement loop region, with a base composition of A 34.0%, G 13.5%, T 28.7% and C 23.9%. All of the protein-coding genes initiate with the orthodox ATG start codon execpt for Nd2 and Nd3 begin with ATT, Nd4 and Nd5, start with GTG and ATA, respectively. Four types of stop codons are used by the coding genes, including TAA for Nd1, Cox1, Cox2, Atp8, Atp6, Nd4L, Nd5, Nd6, TAG for Nd2, AGA for Cytb, and an incomplete stop codon T for Cox3, Nd3 and Nd4. The mito-genomic data of Gansu mole, S. oweni will be useful in determining its taxonomic status within Talpidae.

  13. Application of the MOLE in post-nuclear accident characterization

    SciTech Connect

    Johnson, S.J.; Alvarez, J.L.

    1981-01-01

    Following a nuclear accident there is a need to determine the chemical composition of materials in liquid, solid and gaseous form, the crystalline structure of solids, the size and chemical composition of particles, and the chemical characterization of contaminants on surfaces. This analytical information is required to reconstruct the accident scenario, to select decontamination methods, and to determine future safety requirements. The MOLE (Molecular Optical Laser Examiner) is a Raman microprobe system which has proven to be a valuable analytical tool in providing this type of chemical information. It can determine the chemical species of polyatomic molecules and ions having characteristic Raman spectra. As little as 1 picogram of a component or a 1 ..mu..m particle can be analyzed. The imaging system can also provide mapping of selected components on a surface. A system description, sample handling techniques, and applications are presented. Specific applications to the Three Mile Island-Unit 2 accident are also addressed.

  14. A fossil aardvark (Mammalia, Tubulidentata) from the lower Pliocene of Chad

    NASA Astrophysics Data System (ADS)

    Lehmann, Thomas; Vignaud, Patrick; Mackaye, Hassane Taïsso; Brunet, Michel

    2004-12-01

    The Mission Paléoanthropologique Franco-Tchadienne (MPFT) found a new species of Orycteropodidae (Mammalia, Tubulidentata) in the Kollé fossiliferous sector, northern Chad. After Orycteropus abundulafus [Journal of Vertebrate Paleontology 20 (1) (2000) 205-209; Lehmann, T., Vignaud, P., Likius A., Brunet M., in press. A new Orycteropodidae (Mammalia, Tubulidentata) in the Mio-Pliocene of Northern Chad. Zool. J. Linnean Soc.], this specimen is the second complete skeleton of fossil aardvark found in the Djurab desert. It is the first complete representative of an Orycteropus species found in the Pliocene of Africa. In regard to the Miocene fossil aardvarks, this new taxon, Orycteropus djourabensis nov. sp., shows more affinities with the extant O. afer. The main differences are the larger teeth and the shorter hand in the fossil form. Kossom Bougoudi and Kollé represent a chronological series that gives a unique opportunity for studying the evolution of the African Tubulidentata around the Mio-Pliocene boundary (5.5-4 My). The new species is distinct from the older Chadian Orycteropodid from KB and it embodies the taxonomic turnover that took place within the order Tubulidentata around this boundary in Africa. Moreover, this new species is the oldest known Orycteropus species that clearly belongs to the modern forms including the extant aardvark.

  15. Adult neurogenesis and its anatomical context in the hippocampus of three mole-rat species

    PubMed Central

    Amrein, Irmgard; Becker, Anton S.; Engler, Stefanie; Huang, Shih-hui; Müller, Julian; Slomianka, Lutz; Oosthuizen, Maria K.

    2014-01-01

    African mole-rats (family Bathyergidae) are small to medium sized, long-lived, and strictly subterranean rodents that became valuable animal models as a result of their longevity and diversity in social organization. The formation and integration of new hippocampal neurons in adult mammals (adult hippocampal neurogenesis, AHN) correlates negatively with age and positively with habitat complexity. Here we present quantitative data on AHN in wild-derived mole-rats of 1 year and older, and briefly describe its anatomical context including markers of neuronal function (calbindin and parvalbumin). Solitary Cape mole-rats (Georychus capensis), social highveld mole-rats (Cryptomys hottentotus pretoriae), and eusocial naked mole-rats (Heterocephalus glaber) were assessed. Compared to other rodents, the hippocampal formation in mole-rats is small, but shows a distinct cytoarchitecture in the dentate gyrus and CA1. Distributions of the calcium-binding proteins differ from those seen in rodents; e.g., calbindin in CA3 of naked mole-rats distributes similar to the pattern seen in early primate development, and calbindin staining extends into the stratum lacunosum-moleculare of Cape mole-rats. Proliferating cells and young neurons are found in low numbers in the hippocampus of all three mole-rat species. Resident granule cell numbers are low as well. Proliferating cells expressed as a percentage of resident granule cells are in the range of other rodents, while the percentage of young neurons is lower than that observed in surface dwelling rodents. Between mole-rat species, we observed no difference in the percentage of proliferating cells. The percentages of young neurons are high in social highveld and naked mole-rats, and low in solitary Cape mole-rats. The findings support that proliferation is regulated independently of average life expectancy and habitat. Instead, neuronal differentiation reflects species-specific demands, which appear lower in subterranean rodents. PMID

  16. Possible incipient sympatric ecological speciation in blind mole rats (Spalax)

    PubMed Central

    Hadid, Yarin; Tzur, Shay; Pavlíček, Tomáš; Šumbera, Radim; Šklíba, Jan; Lövy, Matěj; Fragman-Sapir, Ori; Beiles, Avigdor; Arieli, Ran; Raz, Shmuel; Nevo, Eviatar

    2013-01-01

    Sympatric speciation has been controversial since it was first proposed as a mode of speciation. Subterranean blind mole rats (Spalacidae) are considered to speciate allopatrically or peripatrically. Here, we report a possible incipient sympatric adaptive ecological speciation in Spalax galili (2n = 52). The study microsite (0.04 km2) is sharply subdivided geologically, edaphically, and ecologically into abutting barrier-free ecologies divergent in rock, soil, and vegetation types. The Pleistocene Alma basalt abuts the Cretaceous Senonian Kerem Ben Zimra chalk. Only 28% of 112 plant species were shared between the soils. We examined mitochondrial DNA in the control region and ATP6 in 28 mole rats from basalt and in 14 from chalk habitats. We also sequenced the complete mtDNA (16,423 bp) of four animals, two from each soil type. Remarkably, the frequency of all major haplotype clusters (HC) was highly soil-biased. HCI and HCII are chalk biased. HC-III was abundant in basalt (36%) but absent in chalk; HC-IV was prevalent in basalt (46.5%) but was low (20%) in chalk. Up to 40% of the mtDNA diversity was edaphically dependent, suggesting constrained gene flow. We identified a homologous recombinant mtDNA in the basalt/chalk studied area. Phenotypically significant divergences differentiate the two populations, inhabiting different soils, in adaptive oxygen consumption and in the amount of outside-nest activity. This identification of a possible incipient sympatric adaptive ecological speciation caused by natural selection indirectly refutes the allopatric alternative. Sympatric ecological speciation may be more prevalent in nature because of abundant and sharply abutting divergent ecologies. PMID:23359700

  17. Comparative Morphology of the Penis and Clitoris in Four Species of Moles (Talpidae).

    PubMed

    Sinclair, Adriane Watkins; Glickman, Stephen; Catania, Kenneth; Shinohara, Akio; Baskin, Lawrence; Cunha, Gerald R

    2017-03-02

    The penile and clitoral anatomy of four species of Talpid moles (broad-footed, star-nosed, hairy-tailed, and Japanese shrew moles) were investigated to define penile and clitoral anatomy and to examine the relationship of the clitoral anatomy with the presence or absence of ovotestes. The ovotestis contains ovarian tissue and glandular tissue resembling fetal testicular tissue and can produce androgens. The ovotestis is present in star-nosed and hairy-tailed moles, but not in broad-footed and Japanese shrew moles. Using histology, three-dimensional reconstruction, and morphometric analysis, sexual dimorphism was examined with regard to a nine feature masculine trait score that included perineal appendage length (prepuce), anogenital distance, and presence/absence of bone. The presence/absence of ovotestes was discordant in all four mole species for sex differentiation features. For many sex differentiation features, discordance with ovotestes was observed in at least one mole species. The degree of concordance with ovotestes was highest for hairy-tailed moles and lowest for broad-footed moles. In relationship to phylogenetic clade, sex differentiation features also did not correlate with the similarity/divergence of the features and presence/absence of ovotestes. Hairy-tailed and Japanese shrew moles reside in separated clades, but they exhibit a high degree of congruence. Broad-footed and hairy-tailed moles reside within the same clade but had one of the lowest correlations in features and presence/absence of ovotestes. Thus, phylogenetic affinity and the presence/absence of ovotestes are poor predictors for most sex differentiation features within mole external genitalia.

  18. High-molecular-mass hyaluronan mediates the cancer resistance of the naked mole rat.

    PubMed

    Tian, Xiao; Azpurua, Jorge; Hine, Christopher; Vaidya, Amita; Myakishev-Rempel, Max; Ablaeva, Julia; Mao, Zhiyong; Nevo, Eviatar; Gorbunova, Vera; Seluanov, Andrei

    2013-07-18

    The naked mole rat (Heterocephalus glaber) displays exceptional longevity, with a maximum lifespan exceeding 30 years. This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years. In addition to their longevity, naked mole rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single incidence of cancer. Here we identify a mechanism responsible for the naked mole rat's cancer resistance. We found that naked mole-rat fibroblasts secrete extremely high-molecular-mass hyaluronan (HA), which is over five times larger than human or mouse HA. This high-molecular-mass HA accumulates abundantly in naked mole-rat tissues owing to the decreased activity of HA-degrading enzymes and a unique sequence of hyaluronan synthase 2 (HAS2). Furthermore, the naked mole-rat cells are more sensitive to HA signalling, as they have a higher affinity to HA compared with mouse or human cells. Perturbation of the signalling pathways sufficient for malignant transformation of mouse fibroblasts fails to transform naked mole-rat cells. However, once high-molecular-mass HA is removed by either knocking down HAS2 or overexpressing the HA-degrading enzyme, HYAL2, naked mole-rat cells become susceptible to malignant transformation and readily form tumours in mice. We speculate that naked mole rats have evolved a higher concentration of HA in the skin to provide skin elasticity needed for life in underground tunnels. This trait may have then been co-opted to provide cancer resistance and longevity to this species.

  19. Pacific Mole Crab (Emerita analoga) Abundance in Correlation with Waste Water Effluence

    NASA Astrophysics Data System (ADS)

    Sun, L.; Dangerfield, L.; Minor, D.; Subedar, R.

    2012-12-01

    Previous studies have shown that pollutants such as ammonia and copper have had negative effects on marine invertebrate lifecycles. Along the Pacific Coast of California, a filter feeding invertebrate, the Pacific mole crab, Emerita analoga, is exposed to such pollutants regularly. In San Francisco, habitats for populations of Pacific mole crabs are located near the Oceanside Water Pollution Control Plant, which dumps waste water 4.5 miles off the coast. Due to this disturbance at the south end of Ocean Beach, we hypothesize that there is a negative correlation between the abundance of mole crabs and the levels of copper, zinc and ammonia in sewage released from the Oceanside plant each year. By analyzing four years of Pacific mole crab abundance data and utilizing yearly waste water discharge figures, we found that there is a slight negative correlation (-0.67057) between mole crab abundances and the total amount of waste water being released annually. The amount of copper released from 2007-2010 and the abundance of E. analoga also has a slight negative correlation (-0.6714). The correlation between Pacific mole crab abundance and the total amount of zinc is also a slightly negative (-0.48434). However, the correlation between the abundance of mole crabs and total amount of ammonia released is positive (0.4497). Further data are needed to ascertain the relationship between the abundance of the Pacific mole crab and the amount of pollutants released from nearby waste water treatment plants.

  20. Whole-Genome Sequence of a Novel Hantavirus Isolated from the European Mole (Talpa europaea)

    PubMed Central

    Gu, Se Hun; Hejduk, Janusz; Markowski, Janusz; Markowski, Marcin; Liberski, Paweł P.

    2015-01-01

    The complete genome sequence of Nova virus, a novel hantavirus isolated from a European mole (Talpa europaea) captured in central Poland, was determined. The availability of this sequence will facilitate the search for other mole-borne hantaviruses and will accelerate the acquisition of new knowledge about their phylogeography and evolutionary origin. PMID:26021917

  1. What's the Diagnosis? An Inquiry-Based Activity Focusing on Mole-Mass Conversions

    ERIC Educational Resources Information Center

    Bruck, Laura B.; Towns, Marcy H.

    2011-01-01

    An inquiry-based mole-to-mass activity is presented associated with the analysis of blood. Students working in groups choose between two medical cases to determine if the "patient" has higher or lower concentrations of minerals than normal. The data are presented such that students must convert moles to mass in order to compare the patient values…

  2. The Naked Mole Rat Genome Resource: facilitating analyses of cancer and longevity-related adaptations

    PubMed Central

    Keane, Michael; Craig, Thomas; Alföldi, Jessica; Berlin, Aaron M.; Johnson, Jeremy; Seluanov, Andrei; Gorbunova, Vera; Di Palma, Federica; Lindblad-Toh, Kerstin; Church, George M.; de Magalhães, João Pedro

    2014-01-01

    Motivation: The naked mole rat (Heterocephalus glaber) is an exceptionally long-lived and cancer-resistant rodent native to East Africa. Although its genome was previously sequenced, here we report a new assembly sequenced by us with substantially higher N50 values for scaffolds and contigs. Results: We analyzed the annotation of this new improved assembly and identified candidate genomic adaptations which may have contributed to the evolution of the naked mole rat’s extraordinary traits, including in regions of p53, and the hyaluronan receptors CD44 and HMMR (RHAMM). Furthermore, we developed a freely available web portal, the Naked Mole Rat Genome Resource (http://www.naked-mole-rat.org), featuring the data and results of our analysis, to assist researchers interested in the genome and genes of the naked mole rat, and also to facilitate further studies on this fascinating species. Availability and implementation: The Naked Mole Rat Genome Resource is freely available online at http://www.naked-mole-rat.org. This resource is open source and the source code is available at https://github.com/maglab/naked-mole-rat-portal. Contact: jp@senescence.info PMID:25172923

  3. Trading new neurons for status: Adult hippocampal neurogenesis in eusocial Damaraland mole-rats.

    PubMed

    Oosthuizen, M K; Amrein, I

    2016-06-02

    Diversity in social structures, from solitary to eusocial, is a prominent feature of subterranean African mole-rat species. Damaraland mole-rats are eusocial, they live in colonies that are characterized by a reproductive division of labor and a subdivision into castes based on physiology and behavior. Damaraland mole-rats are exceptionally long lived and reproductive animals show delayed aging compared to non-reproductive animals. In the present study, we described the hippocampal architecture and the rate of hippocampal neurogenesis of wild-derived, adult Damaraland mole-rats in relation to sex, relative age and social status or caste. Overall, Damaraland mole-rats were found to have a small hippocampus and low rates of neurogenesis. We found no correlation between neurogenesis and sex or relative age. Social status or caste was the most prominent modulator of neurogenesis. An inverse relationship between neurogenesis and social status was apparent, with queens displaying the lowest neurogenesis while the worker mole-rats had the most. As there is no natural progression from one caste to another, social status within a colony was relatively stable and is reflected in the level of neurogenesis. Our results correspond to those found in the naked mole-rat, and may reflect an evolutionary and environmentally conserved trait within social mole-rat species.

  4. Eye development in the Cape dune mole rat.

    PubMed

    Nikitina, Natalya V; Kidson, Susan H

    2014-03-01

    Studies on mammalian species with naturally reduced eyes can provide valuable insights into the evolutionary developmental mechanisms underlying the reduction of the eye structures. Because few naturally microphthalmic animals have been studied and eye reduction must have evolved independently in many of the modern groups, novel evolutionary developmental models for eye research have to be sought. Here, we present a first report on embryonic eye development in the Cape dune mole rat, Bathyergus suillus. The eyes of these animals contain all the internal structures characteristic of the normal eye but exhibit abnormalities in the anterior chamber structures. The lens is small but develops normally and exhibits a normal expression of α- and γ-crystallins. One of the interesting features of these animals is an extremely enlarged and highly pigmented ciliary body. In order to understand the molecular basis of this unusual feature, the expression pattern of an early marker of the ciliary zone, Ptmb4, was investigated in this animal. Surprisingly, in situ hybridization results revealed that Ptmb4 expression was absent from the ciliary body zone of the developing Bathyergus eye.

  5. Acanthocephala Parasite (Profilicollis spp.) Loads in Correlation to Pacific Mole Crab (Emerita analoga) Size

    NASA Astrophysics Data System (ADS)

    Cheng, T.; Huang, S.; Galathe, M.; Jenkins, M.; Ramirez, A.; Crosby, L.; Barrera, J.; FitzHoward, S.

    2013-12-01

    Since 2002, San Francisco Bay students have been conducting marine ecosystem monitoring through a joint project with the Long-term Monitoring Program and Experiential Training for Students (LiMPETS), in conjunction with the Gulf of Farallones National Marine Sanctuary. Each year students collect population and demographic data on Pacific mole crabs (Emerita analoga), an indicator species that lives in the sandy beach habitat in temperate regions along the Pacific Ocean. Pacific mole crabs are filter feeding crustaceans that inhabit the intertidal swash zone and are known to be an intermediate host for parasitic ';spiny-headed' worms in the phylum Acanthocephala (Profilicollis spp.). Sampling takes place during their reproductive period, which occurs from spring to fall, and includes measuring total body length of the Pacific mole crabs and dissecting them to determine presence of Acanthocephalan parasites. We hypothesize that due to larger body mass, larger Pacific mole crabs will have a greater number of Acanthocephala parasites.We conducted several analyses using the LiMPETS long-term data. Specifically, we compared body length, crab gender, and parasite abundance from Pacific mole crabs sampled from four beaches located in the county and city of San Francisco. Our results indicated that larger Pacific mole crabs do not necessarily have more parasites, but are more likely to have at least one parasite, while female Pacific mole crabs carrying eggs, have more parasites than males or females without eggs. We also found that parasite loads per mole crab was highest in the spring. Further analysis will be conducted to determine factors affecting Pacific mole crab parasite loads. Studying Pacific mole crabs help evaluate the health of California's intertidal systems and how human activities, geologic changes, and climate changes all make huge impacts to the intertidal ecosystems.

  6. Making Mountains out of Molehills: Sediment Transport by the European Mole (Talpa europaea)

    NASA Astrophysics Data System (ADS)

    Milledge, D.; Loveless, J. C.; Warburton, J.; Densmore, A. L.

    2013-12-01

    Despite its widespread occurrence (across Europe and Eastern North America) the significance of the burrowing activity of the European Mole for sediment transport in the Northern Hemisphere has not been well quantified. In many areas this may have been the dominant mechanism of hillslope sediment transport over the last one to two millenia. The European Mole (Talpa europaea) is prevalent across the UK, particularly in fertile soils. It is highly fossorial, living almost its entire 3-6 year life in a network of tunnels that it maintains to catch prey. Moles can rapidly excavate large amounts of soil (~6 kg in 20 minutes) with waste soil generally pushed to the surface to form molehills. In this study we quantify sediment flux due to mole burrowing based on measured molehill sizes and geometries and estimates of mole hill production rates from time lapse photography. We examine the evolution of the molehills after production through repeat survey of in-situ molehills in the field and rainfall simulation experiments to accelerate degradation in the laboratory. Our initial findings suggest that: 1) molehill masses are generally log-normally distributed with a geometric mean ~1.4 kg; 2) moles move approximately 1.5 times as much soil as earthworms; and 3) the sediment flux due to moles is a non-linear function of the local slope.

  7. Selective inflammatory pain insensitivity in the African naked mole-rat (Heterocephalus glaber).

    PubMed

    Park, Thomas J; Lu, Ying; Jüttner, René; Smith, Ewan St J; Hu, Jing; Brand, Antje; Wetzel, Christiane; Milenkovic, Nevena; Erdmann, Bettina; Heppenstall, Paul A; Laurito, Charles E; Wilson, Steven P; Lewin, Gary R

    2008-01-01

    In all mammals, tissue inflammation leads to pain and behavioral sensitization to thermal and mechanical stimuli called hyperalgesia. We studied pain mechanisms in the African naked mole-rat, an unusual rodent species that lacks pain-related neuropeptides (e.g., substance P) in cutaneous sensory fibers. Naked mole-rats show a unique and remarkable lack of pain-related behaviors to two potent algogens, acid and capsaicin. Furthermore, when exposed to inflammatory insults or known mediators, naked mole-rats do not display thermal hyperalgesia. In contrast, naked mole-rats do display nocifensive behaviors in the formalin test and show mechanical hyperalgesia after inflammation. Using electrophysiology, we showed that primary afferent nociceptors in naked mole-rats are insensitive to acid stimuli, consistent with the animal's lack of acid-induced behavior. Acid transduction by sensory neurons is observed in birds, amphibians, and fish, which suggests that this tranduction mechanism has been selectively disabled in the naked mole-rat in the course of its evolution. In contrast, nociceptors do respond vigorously to capsaicin, and we also show that sensory neurons express a transient receptor potential vanilloid channel-1 ion channel that is capsaicin sensitive. Nevertheless, the activation of capsaicin-sensitive sensory neurons in naked mole-rats does not produce pain-related behavior. We show that capsaicin-sensitive nociceptors in the naked mole-rat are functionally connected to superficial dorsal horn neurons as in mice. However, the same nociceptors are also functionally connected to deep dorsal horn neurons, a connectivity that is rare in mice. The pain biology of the naked mole-rat is unique among mammals, thus the study of pain mechanisms in this unusual species can provide major insights into what constitutes "normal" mammalian nociception.

  8. Pregnancy outcome with coexisting mole after intracytoplasmic sperm injection: A case series

    PubMed Central

    Rao, Asha R.; Dafle, Karishma; Padmashri, G.; Rao, Damodar R.; Sivakumar, N. C.

    2015-01-01

    Partial/complete hydatidiform mole with coexisting fetus is a rare condition. Optimal management is a challenge that remains a dilemma since these pregnancies are associated with maternal as well as fetal complications including hemorrhage, preeclampsia, thromboembolic disease, intra uterine demise and increased risk of persistent trophoblastic disease. Here we report 2 cases of partial mole with live fetus after ICSI and a case of complete mole with coexisting fetus after ICSI in a turner mosaic that resulted in a live birth. PMID:26538863

  9. What Are Students' Initial Ideas about "Amount of Substance"? "Is There a Specific Weight for a Mole?"

    ERIC Educational Resources Information Center

    Claesgens, Jennifer; Stacy, Angelica

    Analyzes the role of students' prior knowledge in their emerging understanding of the mole. The research question this study seeks to answer is what knowledge, if any, do student have regarding the mole and what prior knowledge do they access when presented problems regarding the nature of the mole. Data collection focuses on student knowledge…

  10. The Mole and Avogadro's Number: A Forced Fusion of Ideas for Teaching Purposes

    ERIC Educational Resources Information Center

    Hawthorne, Robert M., Jr.

    1973-01-01

    Reports a review of existing texts in which it was found that many textbooks exist which do not make any particular connection between Avogadro's number and the mole. Some books do not mention or use Avogadro's number at all. (DF)

  11. Genome sequencing reveals insights into physiology and longevity of the naked mole rat.

    PubMed

    Kim, Eun Bae; Fang, Xiaodong; Fushan, Alexey A; Huang, Zhiyong; Lobanov, Alexei V; Han, Lijuan; Marino, Stefano M; Sun, Xiaoqing; Turanov, Anton A; Yang, Pengcheng; Yim, Sun Hee; Zhao, Xiang; Kasaikina, Marina V; Stoletzki, Nina; Peng, Chunfang; Polak, Paz; Xiong, Zhiqiang; Kiezun, Adam; Zhu, Yabing; Chen, Yuanxin; Kryukov, Gregory V; Zhang, Qiang; Peshkin, Leonid; Yang, Lan; Bronson, Roderick T; Buffenstein, Rochelle; Wang, Bo; Han, Changlei; Li, Qiye; Chen, Li; Zhao, Wei; Sunyaev, Shamil R; Park, Thomas J; Zhang, Guojie; Wang, Jun; Gladyshev, Vadim N

    2011-10-12

    The naked mole rat (Heterocephalus glaber) is a strictly subterranean, extraordinarily long-lived eusocial mammal. Although it is the size of a mouse, its maximum lifespan exceeds 30 years, making this animal the longest-living rodent. Naked mole rats show negligible senescence, no age-related increase in mortality, and high fecundity until death. In addition to delayed ageing, they are resistant to both spontaneous cancer and experimentally induced tumorigenesis. Naked mole rats pose a challenge to the theories that link ageing, cancer and redox homeostasis. Although characterized by significant oxidative stress, the naked mole rat proteome does not show age-related susceptibility to oxidative damage or increased ubiquitination. Naked mole rats naturally reside in large colonies with a single breeding female, the 'queen', who suppresses the sexual maturity of her subordinates. They also live in full darkness, at low oxygen and high carbon dioxide concentrations, and are unable to sustain thermogenesis nor feel certain types of pain. Here we report the sequencing and analysis of the naked mole rat genome, which reveals unique genome features and molecular adaptations consistent with cancer resistance, poikilothermy, hairlessness and insensitivity to low oxygen, and altered visual function, circadian rythms and taste sensing. This information provides insights into the naked mole rat's exceptional longevity and ability to live in hostile conditions, in the dark and at low oxygen. The extreme traits of the naked mole rat, together with the reported genome and transcriptome information, offer opportunities for understanding ageing and advancing other areas of biological and biomedical research.

  12. Hypersensitivity to contact inhibition provides a clue to cancer resistance of naked mole-rat.

    PubMed

    Seluanov, Andrei; Hine, Christopher; Azpurua, Jorge; Feigenson, Marina; Bozzella, Michael; Mao, Zhiyong; Catania, Kenneth C; Gorbunova, Vera

    2009-11-17

    The naked mole-rat is the longest living rodent with a maximum lifespan exceeding 28 years. In addition to its longevity, naked mole-rats have an extraordinary resistance to cancer as tumors have never been observed in these rodents. Furthermore, we show that a combination of activated Ras and SV40 LT fails to induce robust anchorage-independent growth in naked mole-rat cells, while it readily transforms mouse fibroblasts. The mechanisms responsible for the cancer resistance of naked mole-rats were unknown. Here we show that naked mole-rat fibroblasts display hypersensitivity to contact inhibition, a phenomenon we termed "early contact inhibition." Contact inhibition is a key anticancer mechanism that arrests cell division when cells reach a high density. In cell culture, naked mole-rat fibroblasts arrest at a much lower density than those from a mouse. We demonstrate that early contact inhibition requires the activity of p53 and pRb tumor suppressor pathways. Inactivation of both p53 and pRb attenuates early contact inhibition. Contact inhibition in human and mouse is triggered by the induction of p27(Kip1). In contrast, early contact inhibition in naked mole-rat is associated with the induction of p16(Ink4a). Furthermore, we show that the roles of p16(Ink4a) and p27(Kip1) in the control of contact inhibition became temporally separated in this species: the early contact inhibition is controlled by p16(Ink4a), and regular contact inhibition is controlled by p27(Kip1). We propose that the additional layer of protection conferred by two-tiered contact inhibition contributes to the remarkable tumor resistance of the naked mole-rat.

  13. Atypical mole syndrome and dysplastic nevi: identification of populations at risk for developing melanoma - review article

    PubMed Central

    Silva, Juliana Hypólito; de Sá, Bianca Costa Soares; de Ávila, Alexandre Leon Ribeiro; Landman, Gilles; Neto, João Pedreira Duprat

    2011-01-01

    Atypical Mole Syndrome is the most important phenotypic risk factor for developing cutaneous melanoma, a malignancy that accounts for about 80% of deaths from skin cancer. Because the diagnosis of melanoma at an early stage is of great prognostic relevance, the identification of Atypical Mole Syndrome carriers is essential, as well as the creation of recommended preventative measures that must be taken by these patients. PMID:21552679

  14. Australia's first fossil marsupial mole (Notoryctemorphia) resolves controversies about their evolution and palaeoenvironmental origins.

    PubMed

    Archer, Michael; Beck, Robin; Gott, Miranda; Hand, Suzanne; Godthelp, Henk; Black, Karen

    2011-05-22

    Fossils of a marsupial mole (Marsupialia, Notoryctemorphia, Notoryctidae) are described from early Miocene deposits in the Riversleigh World Heritage Area, northwestern Queensland, Australia. These represent the first unequivocal fossil record of the order Notoryctemorphia, the two living species of which are among the world's most specialized and bizarre mammals, but which are also convergent on certain fossorial placental mammals (most notably chrysochlorid golden moles). The fossil remains are genuinely 'transitional', documenting an intermediate stage in the acquisition of a number of specializations and showing that one of these-the dental morphology known as zalambdodonty-was acquired via a different evolutionary pathway than in placentals. They, thus, document a clear case of evolutionary convergence (rather than parallelism) between only distantly related and geographically isolated mammalian lineages-marsupial moles on the island continent of Australia and placental moles on most other, at least intermittently connected continents. In contrast to earlier presumptions about a relationship between the highly specialized body form of the blind, earless, burrowing marsupial moles and desert habitats, it is now clear that archaic burrowing marsupial moles were adapted to and probably originated in wet forest palaeoenvironments, preadapting them to movement through drier soils in the xeric environments of Australia that developed during the Neogene.

  15. SHORT COMMUNICATION: Comments on recent proposals for redefining the mole and kilogram

    NASA Astrophysics Data System (ADS)

    Leonard, B. P.

    2010-06-01

    The fundamental concept of the mole requires the number of entities comprising one mole, i.e. Avogadro's number, to be exactly equal to the gram-to-dalton mass ratio. If this compatibility condition is to be satisfied, the mole, the kilogram and the dalton cannot all be defined independently. This note concerns recent Metrologia publications that do, however, propose independent definitions of all three quantities: the mole by fixing the value of Avogadro's number and the kilogram by fixing the value of the Planck constant, while retaining the current carbon-12-based dalton. Adoption of these incompatible definitions would likely cause serious widespread confusion and might even result in a split in scholarly and technical communication between the quantum physics and chemistry communities. Other entirely compatible alternatives are possible: either retaining the current (inexact) carbon-12-based mole and dalton with an independently redefined kilogram or redefining the mole by fixing the value of Avogadro's number, with a compatible dalton that is exact in terms of the redefined kilogram.

  16. Blunted neuronal calcium response to hypoxia in naked mole-rat hippocampus.

    PubMed

    Peterson, Bethany L; Larson, John; Buffenstein, Rochelle; Park, Thomas J; Fall, Christopher P

    2012-01-01

    Naked mole-rats are highly social and strictly subterranean rodents that live in large communal colonies in sealed and chronically oxygen-depleted burrows. Brain slices from naked mole-rats show extreme tolerance to hypoxia compared to slices from other mammals, as indicated by maintenance of synaptic transmission under more hypoxic conditions and three fold longer latency to anoxic depolarization. A key factor in determining whether or not the cellular response to hypoxia is reversible or leads to cell death may be the elevation of intracellular calcium concentration. In the present study, we used fluorescent imaging techniques to measure relative intracellular calcium changes in CA1 pyramidal cells of hippocampal slices during hypoxia. We found that calcium accumulation during hypoxia was significantly and substantially attenuated in slices from naked mole-rats compared to slices from laboratory mice. This was the case for both neonatal (postnatal day 6) and older (postnatal day 20) age groups. Furthermore, while both species demonstrated more calcium accumulation at older ages, the older naked mole-rats showed a smaller calcium accumulation response than even the younger mice. A blunted intracellular calcium response to hypoxia may contribute to the extreme hypoxia tolerance of naked mole-rat neurons. The results are discussed in terms of a general hypothesis that a very prolonged or arrested developmental process may allow adult naked mole-rat brain to retain the hypoxia tolerance normally only seen in neonatal mammals.

  17. Rediscovery of Meristaspis lateralis (Kolenati) (Acari: Mesostigmata: Spinturnicidae) parasitizing the Egyptian fruit bat, Rousettus aegyptiacus (Geoffroy) (Mammalia: Chiroptera), with a key to mites of bats in Egypt.

    PubMed

    Negm, Mohamed W; Fakeer, Mahmoud M

    2014-04-01

    Faunistic information about bat mites in Egypt is scarce. Collection records of parasitic mites, Meristaspis lateralis (Kolenati, 1856) (Mesostigmata: Spinturnicidae), are reported from the Egyptian fruit bat, Rousettus aegyptiacus (Geoffroy, 1810) (Mammalia: Chiroptera) in Assiut Governorate, Egypt. Seven species of bat mites are recognized from Egypt to date. A host-parasite checklist and an identification key to these species are presented.

  18. Epidermal sensory organs of moles, shrew moles, and desmans: a study of the family talpidae with comments on the function and evolution of Eimer's organ.

    PubMed

    Catania, K C

    2000-09-01

    The epidermal sensory organs of members of the family Talpidae (moles, shrew-moles, and desmans) were investigated and compared to determine the range of sensory specializations and better understand how they evolved. Small domed mechanosensory organs called 'Eimer's organs' were present on the rhinarium of nearly all species of talpids, but not among the sister group of shrews (Soricidae) or other insectivore families. This suggests that the common ancestor to the talpids possessed Eimer's organs. Two species of moles from the driest habitats did not exhibit Eimer's organs - suggesting that their sensory organs degenerated in response to harsh, abrasive soil conditions. The semi-aquatic desmans uniquely possessed tiny sensory hairs interspersed with their Eimer's organs; these may act to sense water currents. Some species exhibited a subdivided, star-like, rhinarium - resembling an early embryonic stage of the star-nosed mole and providing clues to the evolution of the star. A single genera (Uropsilus) that branched off early in the evolution of the talpids had Eimer's organ-like structures but lacked some typical components. These findings fill a major gap in our knowledge of talpid sensory biology and suggest (1) how Eimer's organs evolved, (2) how the unusual appendages of the star-nosed mole evolved, (3) that the evolution of Eimer's organ is convergent with the mechanosensory push-rod of monotremes. The results also demonstrate the features that distinguish Eimer's organ from similar configurations of sensory receptors in other mammalian skin surfaces. Finally, a mechanism for Eimer's organ function in detecting object and prey specific surface features is proposed.

  19. In-situ Subsurface Science Addressed By The "mole" On The Beagle 2 Mars Lander

    NASA Astrophysics Data System (ADS)

    Richter, L.; Gromov, V. V.; Möhlmann, D.; Kochan, H.; Tokano, T.

    The payload of the Beagle 2 lander of ESA's Mars Express mission includes a regolith- penetrating, tethered "Mole" intended for acquisition of several subsurface soil sam- ples from depths between about 30 cm and some 1E1.5 m. These samples will then be analysed by the Gas Analysis Package instrument on the lander, primarily with re- gard to isotopic composition and to organic molecules. However, after giving a brief overview of the Mole experiment, this paper focuses on additional in-situ science con- ducted by the Beagle 2 Mole system, also referred to as the PLanetary Underground TOol (PLUTO): while it penetrates into the Martian regolith by way of soil displace- ment through the action of an internal hammering mechanism, the Mole will allow mechanical properties of the regolith to be studied as a function of depth - being a first on a Mars mission - and additionally, a temperature sensor mounted on the outside of the Mole will support investigations of soil thermophysical properties and measure- ments of the subsurface temperature profile, again as a first-time achievement. Using a Mole soil penetration theory calibrated by ground-based experiments, regolith bulk density, cohesion, and internal friction angle can be constrained as a function of depth using the Mole penetration path (and retrieval path) vs. time which is measured by a winch rotation sensor indicating the amount of tether extracted by the Mole. The obtained depth profiles of these quantities should provide insight into the depositional history and stratigraphy of the regolith at the site. Measurements of the regolith tem- perature will be conducted by the Mole both as a function of depth during soil in- trusion, and as a function of time for constant depth, as the Mole can be left in the subsurface for periods of days or weeks before it is retrieved, especially during the later part of the Beagle 2 landed mission. Subsurface temperature measurements will support calibrations of Mars regolith

  20. In-situ subsurface science addressed by the Mole on the Beagle 2 Mars lander

    NASA Astrophysics Data System (ADS)

    Richter, L.; Gromov, V.; Kochan, H.; Möhlmann, D.; Tokano, T.

    The payload of the Beagle 2 lander of ESA's Mars Express mission includes a regolithpenetrating, tethered "Mole" intended for acquisition of several subsurface soil sam ples from depths between about 30 cm and some 1E1.5 m. These samples will then be analysed by the Gas Analysis Package instrument on the lander, primarily with regard to isotopic composition and to organic molecules. However, after giving a brief overview of the Mole experiment, this paper focuses on additional in-situ science conducted by the Beagle 2 Mole system, also referred to as the PLanetary Underground TOol (PLUTO): while it penetrates into the Martian regolith by way of soil displacement through the action of an internal hammering mechanism, the Mole will allow mechanical properties of the regolith to be studied as a function of depth - being a first on a Mars mission - and additionally, a temperature sensor mounted on the outside of the Mole will support investigations of soil thermophysical properties and measurements of the subsurface temperature profile, again as a first-time achievement. Using a Mole soil penetration theory calibrated by ground-based experiments, regolith bulk density, cohesion, and internal friction angle can be constrained as a function of depth using the Mole penetration path (and retrieval path) vs. time which is measured by a winch rotation sensor indicating the amount of tether extracted by the Mole. The obtained depth profiles of these quantities should provide insight into the depositional history and stratigraphy of the regolith at the site. Measurements of the regolith temperature will be conducted by the Mole both as a function of depth during soil intrusion, and as a function of time for constant depth, as the Mole can be left in the subsurface for periods of days or weeks before it is retrieved, especially during the later part of the Beagle 2 landed mission. Subsurface temperature measurements will support calibrations of Mars regolith thermophysical

  1. The molecular basis of defective lens development in the Iberian mole

    PubMed Central

    Carmona, F David; Jiménez, Rafael; Collinson, J Martin

    2008-01-01

    Background Fossorial mammals face natural selection pressures that differ from those acting on surface dwelling animals, and these may lead to reduced visual system development. We have studied eye development in a species of true mole, the Iberian mole Talpa occidentalis, and present the molecular basis of abnormal lens development. This is the first embryological developmental study of the eyes of any fossorial mammal at the molecular level. Results Lens fibre differentiation is not completed in the Iberian mole. Although eye development starts normally (similar to other model species), defects are seen after closure of the lens vesicle. PAX6 is not down-regulated in developing lens fibre nuclei, as it is in other species, and there is ectopic expression of FOXE3, a putative downstream effector of PAX6, in some, but not all lens fibres. FOXE3-positive lens fibres continue to proliferate within the posterior compartment of the embryonic lens, but unlike in the mouse, no proliferation was detected anywhere in the postnatal mole lens. The undifferentiated status of the anterior epithelial cells was compromised, and most of them undergo apoptosis. Furthermore, β-crystallin and PROX1 expression patterns are abnormal and our data suggest that genes encoding β-crystallins are not directly regulated by PAX6, c-MAF and PROX1 in the Iberian mole, as they are in other model vertebrates. Conclusion In other model vertebrates, genetic pathways controlling lens development robustly compartmentalise the lens into a simple, undifferentiated, proliferative anterior epithelium, and quiescent, anuclear, terminally differentiated posterior lens fibres. These pathways are not as robust in the mole, and lead to loss of the anterior epithelial phenotype and only partial differentiation of the lens fibres, which continue to express 'epithelial' genes. Paradigms of genetic regulatory networks developed in other vertebrates appear not to hold true for the Iberian mole. PMID:18939978

  2. Differences in cooperative behavior among Damaraland mole rats are consequences of an age-related polyethism

    PubMed Central

    Zöttl, Markus; Vullioud, Philippe; Mendonça, Rute; Torrents Ticó, Miquel; Gaynor, David; Mitchell, Adam; Clutton-Brock, Tim

    2016-01-01

    In many cooperative breeders, the contributions of helpers to cooperative activities change with age, resulting in age-related polyethisms. In contrast, some studies of social mole rats (including naked mole rats, Heterocephalus glaber, and Damaraland mole rats, Fukomys damarensis) suggest that individual differences in cooperative behavior are the result of divergent developmental pathways, leading to discrete and permanent functional categories of helpers that resemble the caste systems found in eusocial insects. Here we show that, in Damaraland mole rats, individual contributions to cooperative behavior increase with age and are higher in fast-growing individuals. Individual contributions to different cooperative tasks are intercorrelated and repeatability of cooperative behavior is similar to that found in other cooperatively breeding vertebrates. Our data provide no evidence that nonreproductive individuals show divergent developmental pathways or specialize in particular tasks. Instead of representing a caste system, variation in the behavior of nonreproductive individuals in Damaraland mole rats closely resembles that found in other cooperatively breeding mammals and appears to be a consequence of age-related polyethism. PMID:27588902

  3. Differences in cooperative behavior among Damaraland mole rats are consequences of an age-related polyethism.

    PubMed

    Zöttl, Markus; Vullioud, Philippe; Mendonça, Rute; Torrents Ticó, Miquel; Gaynor, David; Mitchell, Adam; Clutton-Brock, Tim

    2016-09-13

    In many cooperative breeders, the contributions of helpers to cooperative activities change with age, resulting in age-related polyethisms. In contrast, some studies of social mole rats (including naked mole rats, Heterocephalus glaber, and Damaraland mole rats, Fukomys damarensis) suggest that individual differences in cooperative behavior are the result of divergent developmental pathways, leading to discrete and permanent functional categories of helpers that resemble the caste systems found in eusocial insects. Here we show that, in Damaraland mole rats, individual contributions to cooperative behavior increase with age and are higher in fast-growing individuals. Individual contributions to different cooperative tasks are intercorrelated and repeatability of cooperative behavior is similar to that found in other cooperatively breeding vertebrates. Our data provide no evidence that nonreproductive individuals show divergent developmental pathways or specialize in particular tasks. Instead of representing a caste system, variation in the behavior of nonreproductive individuals in Damaraland mole rats closely resembles that found in other cooperatively breeding mammals and appears to be a consequence of age-related polyethism.

  4. Unraveling the message: insights into comparative genomics of the naked mole-rat.

    PubMed

    Lewis, Kaitlyn N; Soifer, Ilya; Melamud, Eugene; Roy, Margaret; McIsaac, R Scott; Hibbs, Matthew; Buffenstein, Rochelle

    2016-08-01

    Animals have evolved to survive, and even thrive, in different environments. Genetic adaptations may have indirectly created phenotypes that also resulted in a longer lifespan. One example of this phenomenon is the preternaturally long-lived naked mole-rat. This strictly subterranean rodent tolerates hypoxia, hypercapnia, and soil-based toxins. Naked mole-rats also exhibit pronounced resistance to cancer and an attenuated decline of many physiological characteristics that often decline as mammals age. Elucidating mechanisms that give rise to their unique phenotypes will lead to better understanding of subterranean ecophysiology and biology of aging. Comparative genomics could be a useful tool in this regard. Since the publication of a naked mole-rat genome assembly in 2011, analyses of genomic and transcriptomic data have enabled a clearer understanding of mole-rat evolutionary history and suggested molecular pathways (e.g., NRF2-signaling activation and DNA damage repair mechanisms) that may explain the extraordinarily longevity and unique health traits of this species. However, careful scrutiny and re-analysis suggest that some identified features result from incorrect or imprecise annotation and assembly of the naked mole-rat genome: in addition, some of these conclusions (e.g., genes involved in cancer resistance and hairlessness) are rejected when the analysis includes additional, more closely related species. We describe how the combination of better study design, improved genomic sequencing techniques, and new bioinformatic and data analytical tools will improve comparative genomics and ultimately bridge the gap between traditional model and nonmodel organisms.

  5. Naked mole rats exhibit metabolic but not ventilatory plasticity following chronic sustained hypoxia.

    PubMed

    Chung, Danielle; Dzal, Yvonne A; Seow, Allison; Milsom, William K; Pamenter, Matthew E

    2016-03-30

    Naked mole rats are among the most hypoxia-tolerant mammals identified and live in chronic hypoxia throughout their lives. The physiological mechanisms underlying this tolerance, however, are poorly understood. Most vertebrates hyperventilate in acute hypoxia and exhibit an enhanced hyperventilation following acclimatization to chronic sustained hypoxia (CSH). Conversely, naked mole rats do not hyperventilate in acute hypoxia and their response to CSH has not been examined. In this study, we explored mechanisms of plasticity in the control of the hypoxic ventilatory response (HVR) and hypoxic metabolic response (HMR) of freely behaving naked mole rats following 8-10 days of chronic sustained normoxia (CSN) or CSH. Specifically, we investigated the role of the major inhibitory neurotransmitter γ-amino butyric acid (GABA) in mediating these responses. Our study yielded three important findings. First, naked mole rats did not exhibit ventilatory plasticity following CSH, which is unique among adult animals studied to date. Second, GABA receptor (GABAR) antagonism altered breathing patterns in CSN and CSH animals and modulated the acute HVR in CSN animals. Third, naked mole rats exhibited GABAR-dependent metabolic plasticity following long-term hypoxia, such that the basal metabolic rate was approximately 25% higher in normoxic CSH animals than CSN animals, and GABAR antagonists modulated this increase.

  6. Reversed palatal perforation by upper incisors in ageing blind mole-rats (Spalax ehrenbergi)

    PubMed Central

    ZURI, I.; TERKEL, J.

    2001-01-01

    Blind mole-rats (Spalax ehrenbergi) are fossorial solitary rodents that present striking morphological, physiological and behavioural adaptations to the subterranean environment in which they live. Previous studies have shown that mole-rats are specialised in tooth-digging. The rapid eruption-rate of their incisors has evolved to compensate for their excessive wear by excavation. Males use their incisors more than females for digging and fighting, and their rate of incisor eruption is significantly more rapid than in females. Since mole-rats use their incisors for digging throughout the year, we suggest that continuous mechanical pressure on their oral tissues concentrated at the apical sites of the upper incisors leads to cell and tissue fatigue. We provide evidence for 5 stages of palatal perforation by the upper incisors at their apical sites, with maximum perforation characterising aged males. Interspecies comparisons with 7 other fossorial and semi-fossorial rodent species, and with beavers, which expose their incisors to enormous mechanical pressure, revealed that this palatal perforation is unique to the male mole-rat. We suggest that while the fast eruption rate of incisors in the mole-rat compensates for the rapid wear resulting from digging, evolutionary adaptation to continuous tooth-digging is still ongoing, since the physical pressure of digging at the apical sites of the upper incisors leads to tissue destruction, breakage of the palatal bone and possibly to death, as a result of maxillary inflammation. PMID:11760890

  7. iMole, a web based image retrieval system from biomedical literature.

    PubMed

    Giordano, Manuela; Natale, Massimo; Cornaz, Moreno; Ruffino, Andrea; Bonino, Dario; Bucci, Enrico M

    2013-07-01

    iMole is a platform that automatically extracts images and captions from biomedical literature. Images are tagged with terms contained in figure captions by means of a sophisticate text-mining tool. Moreover, iMole allows the user to upload directly their own images within the database and manually tag images by curated dictionary. Using iMole the researchers can develop a proper biomedical image database, storing the images extracted from paper of interest, image found on the web repositories, and their own experimental images. In order to show the functioning of the platform, we used iMole to build a 2DE database. Briefly, tagged 2DE gel images were collected and stored in a searchable 2DE gel database, available to users through an interactive web interface. Images were obtained by automatically parsing 16,608 proteomic publications, which yielded more than 16,500 images. The database can be further expanded by users with images of interest trough a manual uploading process. iMole is available with a preloaded set of 2DE gel data at http://imole.biodigitalvalley.com.

  8. New Aspidoderidae species parasite of Didelphis aurita (Mammalia: Didelphidae): a light and scanning electron microscopy approach.

    PubMed

    Chagas-Moutinho, V A; Sant'anna, V; Oliveira-Menezes, A; De Souza, W

    2014-02-01

    Nematodes of the family Aspidoderidae (Nematoda: Heterakoidea) Skrjabin and Schikobalova, 1947, are widely distributed in the Americas. The family Aspidoderidae includes the subfamilies Aspidoderinae Skrjabin and Schikobalova, 1947, and Lauroiinae Skrjabin and Schikobalova, 1951. These two subfamilies are delineated by the presence or absence of cephalic cordons at the anterior region. The nematodes in the subfamily Aspidoderinae, which includes the genus AspidoderaRailliet and Henry, 1912, are represented by nematodes with anterior cephalic cordons at the anterior end. The nematodes of the genus AspidoderaRailliet and Henry, 1912, are found in the cecum and large intestine of mammals of the orders Edentata, Marsupialia and Rodentia. Species within this genus have many morphological similarities. The use of scanning electron microscopy allows the specific characterization of the species within this genus. In the present work, we describe a new species of Aspidodera parasite of the large intestine of Didelphis aurita (Mammalia: Didelphidae) Wied-Neuwied, 1826, collected from Cachoeiras de Macacu, Rio de Janeiro. The combination of light and scanning electron microscopy allowed us a detailed analysis of this nematode.

  9. Twin Pregnancy with a Complete Hydatidiform Mole and a Coexisting Live Fetus: Rare entity.

    PubMed

    Sheik, Shahila; Al-Riyami, Nihal; Mathew, Namitha R; Al-Sukaiti, Rashid; Qureshi, Asim; Mathew, Mariam

    2015-11-01

    A hydatidiform mole with a coexisting live fetus is a rare occurrence and the optimal management for this condition is not yet known. We report the case of a 32-year-old woman (gravida 3, para 2) who presented to the Sultan Qaboos University Hospital, Muscat, Oman, in March 2012 at 13 gestational weeks with abdominal pain and vaginal bleeding. An ultrasound examination revealed a hydatidiform mole pregnancy coexisting with a live fetus. After extensive counselling, the patient and her husband opted for a conservative management approach. Unfortunately, a hysterotomy had to be performed at 17 gestational weeks due to severe haemorrhage. The postoperative period was uneventful and histopathology results confirmed one complete mole with a coexisting fetus and normal placenta. The patient's serum β-human chorionic gonadotropin level remained normal for 18 months following her surgery.

  10. Moles of a Substance per Cell Is a Highly Informative Dosing Metric in Cell Culture

    PubMed Central

    Wagner, Brett A.; Buettner, Garry R.

    2015-01-01

    Background The biological consequences upon exposure of cells in culture to a dose of xenobiotic are not only dependent on biological variables, but also the physical aspects of experiments e.g. cell number and media volume. Dependence on physical aspects is often overlooked due to the unrecognized ambiguity in the dominant metric used to express exposure, i.e. initial concentration of xenobiotic delivered to the culture medium over the cells. We hypothesize that for many xenobiotics, specifying dose as moles per cell will reduce this ambiguity. Dose as moles per cell can also provide additional information not easily obtainable with traditional dosing metrics. Methods Here, 1,4-benzoquinone and oligomycin A are used as model compounds to investigate moles per cell as an informative dosing metric. Mechanistic insight into reactions with intracellular molecules, differences between sequential and bolus addition of xenobiotic and the influence of cell volume and protein content on toxicity are also investigated. Results When the dose of 1,4-benzoquinone or oligomycin A was specified as moles per cell, toxicity was independent of the physical conditions used (number of cells, volume of medium). When using moles per cell as a dose-metric, direct quantitative comparisons can be made between biochemical or biological endpoints and the dose of xenobiotic applied. For example, the toxicity of 1,4-benzoquinone correlated inversely with intracellular volume for all five cell lines exposed (C6, MDA-MB231, A549, MIA PaCa-2, and HepG2). Conclusions Moles per cell is a useful and informative dosing metric in cell culture. This dosing metric is a scalable parameter that: can reduce ambiguity between experiments having different physical conditions; provides additional mechanistic information; allows direct comparison between different cells; affords a more uniform platform for experimental design; addresses the important issue of repeatability of experimental results, and could

  11. The Naked Mole-Rat Response to Oxidative Stress: Just Deal with It

    PubMed Central

    Lewis, Kaitlyn N.; Andziak, Blazej; Yang, Ting

    2013-01-01

    Abstract Significance: The oxidative stress theory of aging has been the most widely accepted theory of aging providing insights into why we age and die for over 50 years, despite mounting evidence from a multitude of species indicating that there is no direct relationship between reactive oxygen species (ROS) and longevity. Here we explore how different species, including the longest lived rodent, the naked mole-rat, have defied the most predominant aging theory. Recent Advances: In the case of extremely long-lived naked mole-rat, levels of ROS production are found to be similar to mice, antioxidant defenses unexceptional, and even under constitutive conditions, naked mole-rats combine a pro-oxidant intracellular milieu with high, steady state levels of oxidative damage. Clearly, naked mole-rats can tolerate this level of oxidative stress and must have mechanisms in place to prevent its translation into potentially lethal diseases. Critical Issues: In addition to the naked mole-rat, other species from across the phylogenetic spectrum and even certain mouse strains do not support this theory. Moreover, overexpressing or knocking down antioxidant levels alters levels of oxidative damage and even cancer incidence, but does not modulate lifespan. Future Directions: Perhaps, it is not oxidative stress that modulates healthspan and longevity, but other cytoprotective mechanisms that allow animals to deal with high levels of oxidative damage and stress, and nevertheless live long, relatively healthy lifespans. Studying these mechanisms in uniquely long-lived species, like the naked mole-rat, may help us tease out the key contributors to aging and longevity. Antioxid. Redox Signal. 19, 1388–1399. PMID:23025341

  12. Mechanical Performance of Rat, Mouse and Mole Spring Traps, and Possible Implications for Welfare Performance

    PubMed Central

    Baker, Sandra E.; Ellwood, Stephen A.; Tagarielli, Vito L.; Macdonald, David W.

    2012-01-01

    Lethal spring traps are widely used for killing small mammals in the UK. Many require government approval, based primarily on humaneness. However, mole traps and break-back traps for rats and mice are exempt; those available vary widely in price and apparent quality. The EU is considering implementing a Trapping Directive that would alter UK legislation, and a recent report advised the EU that trapping legislation should cover all trapped species and encourage improvement of traps. Mechanical trap performance is often used as an indicator of welfare impact. We examined the mechanical evidence for scope to improve the welfare standards of rat, mouse and mole spring traps. We measured mechanical performance among a range of rat, mouse and mole traps. Impact momentum values varied 6-8 fold, and clamping force values 4-5.5 fold, among traps for killing each species. There was considerable overlap in the performance of rat and mouse traps. Trap-opening angle and spring type were related to impact momentum and clamping force in traps for both species. There was no relationship between price and mechanical performance in traps for any species, except talpa mole traps. We are unable to judge the direct welfare impact of the traps tested, but rather the potential welfare threat associated with their exemption from approval. The wide variation in mechanical performance in traps for each species, overlap in performance between rat and mouse traps and increasing availability of weaker plastic rodent traps indicate considerable scope for improving the humaneness of spring traps for rats, mice and moles. We conclude that all such traps should be subject to the UK approval process. New welfare categories might improve trap standards further. Our results could also help improve rodent trap design and assist consumers in selecting more powerful traps. Many thousands of rats, mice and moles might benefit. PMID:22768073

  13. Trauma and humanitarian translation in Liberia: the tale of open mole.

    PubMed

    Abramowitz, Sharon Alane

    2010-06-01

    The focus of this paper is the intercultural process through which Open Mole and trauma-related mental illnesses are brought together in the postconflict mental health encounter. In this paper, I explore the historical dimension of this process by reviewing the history of Open Mole, and the ways in which it has been interpreted, acted on, and objectified by external observers over the last half-century. Moving into Liberia's recent war and postconflict period, I examine the process by which Open Mole is transformed from a culture-bound disorder into a local idiom of trauma, and how it has become a gateway diagnosis of PTSD-related mental illnesses, and consider how it is produced as an objectified experience of psychiatric disorder in clinical humanitarian contexts. By studying how Open Mole is transformed in the humanitarian encounter, I address the structure and teleology of the humanitarian encounter and challenge some of the foundational assumptions about cultural sensitivity and community-based mental health care in postconflict settings that are prevalent in scholarship and practice today.

  14. A new species of Gryllotalpa mole cricket (Orthoptera: Gryllotalpidae: Gryllotalpinae) from Peninsular Malaysia.

    PubMed

    Tan, Ming Kai; Kamaruddin, Khairul Nizam

    2016-01-19

    A new species of Gryllotalpa mole cricket (Orthoptera: Gryllotalpidae) is described from Bukit Larut, Perak, Peninsular Malaysia: Gryllotalpa permai sp. n. Acoustic analysis of the male calling songs were also provided for Gryllotalpa permai sp. n. and the morphologically similar Gryllotalpa fulvipes.

  15. Plasticity and constraints on social evolution in African mole-rats: ultimate and proximate factors

    PubMed Central

    Faulkes, Chris G.; Bennett, Nigel C.

    2013-01-01

    Here, we review comparative studies of African mole-rats (family Bathyergidae) to explain how constraints acting at the ultimate (environmental) and proximate (organismal) levels have led to convergent gains and losses of sociality within this extensive adaptive radiation of subterranean rodents endemic to sub-Saharan Africa. At the ultimate level, living in environments that range from mesic through to arid has led to both variation and flexibility in social organization among species, culminating in the pinnacle of social evolution in the eusocial naked and Damaraland mole-rats (Heterocephalus glaber and Fukomys damarensis). The common mole-rat (Cryptomys hottentotus) provides a model example of how plasticity in social traits exists within a single species inhabiting areas with different ecological constraint. At the proximate level, reproductive strategies and cooperative breeding may be constrained by the correlated evolution of a suite of traits including physiological suppression of reproduction, the development of physiological and morphological castes, and the mode of ovulatory control and seasonality in breeding. Furthermore, recent neurobiological advances indicate that differential patterns of neurotransmitter expression within the forebrain may underpin (and limit) either a solitary or group living/cooperative lifestyle not only in mole-rats, but also more widely among disparate mammalian taxa. PMID:23569295

  16. Effectiveness of Using Computer-Assisted Supplementary Instruction for Teaching the Mole Concept.

    ERIC Educational Resources Information Center

    Yalcinalp, Serpil; And Others

    1995-01-01

    Examines the effect of computer-assisted instruction (CAI) on students' understanding of chemical formulas and mole concept, and their attitudes toward chemistry and CAI. Reports that students who used the CAI accompanied with lectures scored significantly higher and demonstrated significant improvement in attitudes compared to the control group…

  17. The Atomic Mass Unit, the Avogadro Constant, and the Mole: A Way to Understanding

    ERIC Educational Resources Information Center

    Baranski, Andrzej

    2012-01-01

    Numerous articles have been published that address problems encountered in teaching basic concepts of chemistry such as the atomic mass unit, Avogadro's number, and the mole. The origin of these problems is found in the concept definitions. If these definitions are adjusted for teaching purposes, understanding could be improved. In the present…

  18. Family Wide Molecular Adaptations to Underground Life in African Mole-Rats Revealed by Phylogenomic Analysis.

    PubMed

    Davies, Kalina T J; Bennett, Nigel C; Tsagkogeorga, Georgia; Rossiter, Stephen J; Faulkes, Christopher G

    2015-12-01

    During their evolutionary radiation, mammals have colonized diverse habitats. Arguably the subterranean niche is the most inhospitable of these, characterized by reduced oxygen, elevated carbon dioxide, absence of light, scarcity of food, and a substrate that is energetically costly to burrow through. Of all lineages to have transitioned to a subterranean niche, African mole-rats are one of the most successful. Much of their ecological success can be attributed to a diet of plant storage organs, which has allowed them to colonize climatically varied habitats across sub-Saharan Africa, and has probably contributed to the evolution of their diverse social systems. Yet despite their many remarkable phenotypic specializations, little is known about molecular adaptations underlying these traits. To address this, we sequenced the transcriptomes of seven mole-rat taxa, including three solitary species, and combined new sequences with existing genomic data sets. Alignments of more than 13,000 protein-coding genes encompassed, for the first time, all six genera and the full spectrum of ecological and social variation in the clade. We detected positive selection within the mole-rat clade and along ancestral branches in approximately 700 genes including loci associated with tumorigenesis, aging, morphological development, and sociality. By combining these results with gene ontology annotation and protein-protein networks, we identified several clusters of functionally related genes. This family wide analysis of molecular evolution in mole-rats has identified a suite of positively selected genes, deepening our understanding of the extreme phenotypic traits exhibited by this group.

  19. The sense of touch in the star-nosed mole: from mechanoreceptors to the brain.

    PubMed

    Catania, Kenneth C

    2011-11-12

    Star-nosed moles are somatosensory specialists that explore their environment with 22 appendages that ring their nostrils. The appendages are covered with sensory domes called Eimer's organs. Each organ is associated with a Merkel cell-neurite complex, a lamellated corpuscle, and a series of 5-10 free nerve endings that form a circle of terminal swellings. Anatomy and electrophysiological recordings suggest that Eimer's organs detect small shapes and textures. There are parallels between the organization of the mole's somatosensory system and visual systems of other mammals. The centre of the star is a tactile fovea used for detailed exploration of objects and prey items. The tactile fovea is over-represented in the neocortex, and this is evident in the modular, anatomically visible representation of the star. Multiple maps of the star are visible in flattened cortical preparations processed for cytochrome oxidase or NADPH-diaphorase. Star-nosed moles are the fastest known foragers among mammals, able to identify and consume a small prey item in 120 ms. Together these behavioural and nervous system specializations have made star-nosed moles an intriguing model system for examining general and specialized aspects of mammalian touch.

  20. Background Mole Fractions of Hydrocarbons in North America Determined from NOAA Global Reference Network Data

    NASA Astrophysics Data System (ADS)

    Mielke-Maday, I.

    2015-12-01

    The National Oceanic and Atmospheric Administration (NOAA) Global Monitoring Division (GMD) maintains a global reference network for over 50 trace gas species and analyzes discrete air samples collected by this network throughout the world at the Earth System Research Laboratory in Boulder, Colorado. In particular, flask samples are analyzed for a number of hydrocarbons with policy and health relevance such as ozone precursors, greenhouse gases, and hazardous air pollutants. Because this global network's sites are remote and therefore minimally influenced by local anthropogenic emissions, these data yield information about background ambient mole fractions and can provide a context for observations collected in intensive field campaigns, such as the Front Range Air Pollution and Photochemistry Experiment (FRAPPE), the Southeast Nexus (SENEX) study, and the DISCOVER-AQ deployments. Information about background mole fractions during field campaigns is critical for calculating hydrocarbon enhancements in the region of study and for assessing the extent to which a particular region's local emissions sources contribute to these enhancements. Understanding the geographic variability of the background and its contribution to regional ambient mole fractions is also crucial for the development of realistic regulations. We present background hydrocarbon mole fractions and their ratios in North America using data from air samples collected in the planetary boundary layer at tall towers and aboard aircraft from 2008 to 2014. We discuss the spatial and seasonal variability in these data. We present trends over the time period of measurements and propose possible explanations for these trends.

  1. Reading about the Power of Music: "Mole Music" and "Children of the Stone"

    ERIC Educational Resources Information Center

    Cardany, Audrey Berger

    2016-01-01

    In this article, I review two books that address the power of music for the individual and group. Both books address the benefits of making, learning, and listening to music during times of conflict. The first brief review is David McPhail's picture book "Mole Music." The second is "Children of the Stone: The Power of Music in a…

  2. Shared ancestry between a newfound mole-borne hantavirus and hantaviruses harbored by cricetid rodents.

    PubMed

    Kang, Hae Ji; Bennett, Shannon N; Hope, Andrew G; Cook, Joseph A; Yanagihara, Richard

    2011-08-01

    Discovery of genetically distinct hantaviruses in multiple species of shrews (order Soricomorpha, family Soricidae) and moles (family Talpidae) contests the conventional view that rodents (order Rodentia, families Muridae and Cricetidae) are the principal reservoir hosts and suggests that the evolutionary history of hantaviruses is far more complex than previously hypothesized. We now report on Rockport virus (RKPV), a hantavirus identified in archival tissues of the eastern mole (Scalopus aquaticus) collected in Rockport, TX, in 1986. Pairwise comparison of the full-length S, M, and L genomic segments indicated moderately low sequence similarity between RKPV and other soricomorph-borne hantaviruses. Phylogenetic analyses, using maximum-likelihood and Bayesian methods, showed that RKPV shared a most recent common ancestor with cricetid-rodent-borne hantaviruses. Distributed widely across the eastern United States, the fossorial eastern mole is sympatric and syntopic with cricetid rodents known to harbor hantaviruses, raising the possibility of host-switching events in the distant past. Our findings warrant more-detailed investigations on the dynamics of spillover and cross-species transmission of present-day hantaviruses within communities of rodents and moles.

  3. Identifying the Critical Components for a Conceptual Understanding of the Mole in Secondary Science Classrooms

    ERIC Educational Resources Information Center

    Fang, Su-Chi; Hart, Christina; Clarke, David

    2016-01-01

    The amount of substance and its unit the mole is a basic concept in chemistry. However, previous research has shown that teaching and learning the concept are challenging tasks for both teachers and students. The purpose of this study was to pinpoint the problems which emerge in the teaching and learning process, and provide integrated suggestions…

  4. Neoteny, Prolongation of Youth: From Naked Mole Rats to "Naked Apes" (Humans).

    PubMed

    Skulachev, Vladimir P; Holtze, Susanne; Vyssokikh, Mikhail Y; Bakeeva, Lora E; Skulachev, Maxim V; Markov, Alexander V; Hildebrandt, Thomas B; Sadovnichii, Viktor A

    2017-04-01

    It has been suggested that highly social mammals, such as naked mole rats and humans, are long-lived due to neoteny (the prolongation of youth). In both species, aging cannot operate as a mechanism facilitating natural selection because the pressure of this selection is strongly reduced due to 1) a specific social structure where only the "queen" and her "husband(s)" are involved in reproduction (naked mole rats) or 2) substituting fast technological progress for slow biological evolution (humans). Lists of numerous traits of youth that do not disappear with age in naked mole rats and humans are presented and discussed. A high resistance of naked mole rats to cancer, diabetes, cardiovascular and brain diseases, and many infections explains why their mortality rate is very low and almost age-independent and why their lifespan is more than 30 years, versus 3 years in mice. In young humans, curves of mortality versus age start at extremely low values. However, in the elderly, human mortality strongly increases. High mortality rates in other primates are observed at much younger ages than in humans. The inhibition of the aging process in humans by specific drugs seems to be a promising approach to prolong our healthspan. This might be a way to retard aging, which is already partially accomplished via the natural physiological phenomenon neoteny.

  5. Somatosensory organ topography across the star of the star-nosed mole (Condylura cristata).

    PubMed

    Sawyer, Eva K; Catania, Kenneth C

    2016-04-01

    Quantifying somatosensory receptor distribution in glabrous skin is usually difficult because of the diversity of skin receptor subtypes and their location within the dermis and epidermis. However, the glabrous noses of moles are an exception. In most species of moles, the skin on the nose is covered with domed mechanosensory units known as an Eimer's organs. Eimer's organs contain a stereotyped array of different mechanosensory neurons, meaning that the distribution of mechanosensitive nerve endings can be inferred by visual inspection of the skin surface. Here we detail the distribution of Eimer's organs on the highly derived somatosensory star on the rostrum of the star-nosed mole (Condylura cristata). The star consists of 22 fleshy appendages, or rays, that are covered in Eimer's organs. We find that the density of Eimer's organs increases from proximal to distal locations along the length of the star's rays with a ratio of 1:2.3:3.1 from the surface nearest to the nostril, to the middle part of ray, to the ray tip, respectively. This ratio is comparable to the increase in receptor unit density reported for the human hand, from the palm, to the middle of the digits, to the distal fingertips. We also note that the tactile fovea of the star-nosed mole, located on the medial ventral ray, does not have increased sensory organ density, and we describe these findings in comparison with other sensory fovea.

  6. Somatosensory organ topography across the star of the star-nosed mole (Condylura cristata)

    PubMed Central

    Sawyer, Eva K.; Catania, Kenneth C.

    2015-01-01

    Quantifying somatosensory receptor distribution in glabrous skin is usually difficult due to the diversity of skin receptor subtypes and their location within the dermis and epidermis. However, the glabrous noses of moles are an exception. In most species of moles, the skin on the nose is covered with domed mechanosensory units known as an Eimer’s organs. Eimer’s organs contain a stereotyped array of different mechanosensory neurons, meaning the distribution of mechanosensitive nerve endings can be inferred by visual inspection of the skin surface. Here we detail the distribution of Eimer’s organs on the highly derived somatosensory star on the rostrum of the star-nosed mole (Condylura cristata). The star consists of 22 fleshy appendages, or rays, that are covered in Eimer’s organs. We find that the density of Eimer’s organs increases from proximal to distal along the length of the star’s rays with a ratio of 1: 2.3: 3.1 from the surface nearest to the nostril, to the middle part of ray, to the ray tip, respectively. This ratio is comparable to the increase in receptor unit density reported in the human hand, from the palm to the middle of the digits, to the distal fingertips. We also note that the tactile fovea of the star nosed mole, located on the medial ventral ray, does not have increased sensory organ density, and we describe these findings in comparison to other sensory fovea. PMID:26659700

  7. Evolution of alanine:glyoxylate aminotransferase 1 peroxisomal and mitochondrial targeting. A survey of its subcellular distribution in the livers of various representatives of the classes Mammalia, Aves and Amphibia.

    PubMed

    Danpure, C J; Fryer, P; Jennings, P R; Allsop, J; Griffiths, S; Cunningham, A

    1994-08-01

    As part of a wider study on the molecular evolution of alanine:glyoxylate aminotransferase 1 (AGT1) intracellular compartmentalization, we have determined the subcellular distribution of immunoreactive AGT1, using postembedding protein A-gold immunoelectron microscopy, in the livers of various members of the classes Mammalia, Aves, and Amphibia. As far as organellar distribution is concerned, three categories could be distinguished. In members of the first category (type I), all, or nearly all, of the immunoreactive AGT1 was concentrated within the peroxisomes. In the second category (type II), AGT1 was found more evenly distributed in both peroxisomes and mitochondria. In the third category (type III), AGT1 was localized mainly within the mitochondria with much lower, but widely variable, amounts in the peroxisomes. Type I animals include the human, two great apes (gorilla, orangutan), two Old World monkeys (anubis baboon, Japanese macaque), a New World monkey (white-faced Saki monkey), a lago, morph (European rabbit), a bat (Seba's short-tailed fruit bat), two caviomorph rodents (guinea pig, orange-rumped agouti), and two Australian marsupials (koala, Bennett's wallaby). Type II animals include two New World monkeys (common marmoset, cotton-top tamarin), three prosimians (brown lemur, fat-tailed dwarf lemur, pygmy slow loris), five rodents (a hybrid crested porcupine, Colombian ground squirrel, laboratory rat, laboratory mouse, golden hamster), an American marsupial (grey short-tailed opossum), and a bird (raven). Type III animals include the large tree shrew, three insectivores (common Eurasian mole, European hedgehog, house shrew), four carnivores (domestic cat, ocelot, domestic dog, polecat ferret), and an amphibian (common frog). In addition to these categories, some animals (e.g. guinea pig, common frog) possessed significant amounts of cytosolic AGT1. Whereas the subcellular distribution of AGT1 in some orders (e.g. Insectivora and Carnivora) did not appear

  8. No evidence for mutations in NLRP7 and KHDC3L in women with androgenetic hydatidiform moles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate the mutational spectrum of NLRP7 and KHDC3L (C6orf221) in women with sporadic and recurrent androgenetic complete hydatidiform moles (AnCHM) and biparental hydatidiform moles (BiHM) to address the hypothesis that autosomal recessive mutations in these gene...

  9. The Mole Mapper Study, mobile phone skin imaging and melanoma risk data collected using ResearchKit

    PubMed Central

    Webster, Dan E.; Suver, Christine; Doerr, Megan; Mounts, Erin; Domenico, Lisa; Petrie, Tracy; Leachman, Sancy A.; Trister, Andrew D.; Bot, Brian M.

    2017-01-01

    Sensor-embedded phones are an emerging facilitator for participant-driven research studies. Skin cancer research is particularly amenable to this approach, as phone cameras enable self-examination and documentation of mole abnormalities that may signal a progression towards melanoma. Aggregation and open sharing of this participant-collected data can be foundational for research and the development of early cancer detection tools. Here we describe data from Mole Mapper, an iPhone-based observational study built using the Apple ResearchKit framework. The Mole Mapper app was designed to collect participant-provided images and measurements of moles, together with demographic and behavioral information relating to melanoma risk. The study cohort includes 2,069 participants who contributed 1,920 demographic surveys, 3,274 mole measurements, and 2,422 curated mole images. Survey data recapitulates associations between melanoma and known demographic risks, with red hair as the most significant factor in this cohort. Participant-provided mole measurements indicate an average mole size of 3.95 mm. These data have been made available to engage researchers in a collaborative, multidisciplinary effort to better understand and prevent melanoma. PMID:28195576

  10. The Mole Mapper Study, mobile phone skin imaging and melanoma risk data collected using ResearchKit.

    PubMed

    Webster, Dan E; Suver, Christine; Doerr, Megan; Mounts, Erin; Domenico, Lisa; Petrie, Tracy; Leachman, Sancy A; Trister, Andrew D; Bot, Brian M

    2017-02-14

    Sensor-embedded phones are an emerging facilitator for participant-driven research studies. Skin cancer research is particularly amenable to this approach, as phone cameras enable self-examination and documentation of mole abnormalities that may signal a progression towards melanoma. Aggregation and open sharing of this participant-collected data can be foundational for research and the development of early cancer detection tools. Here we describe data from Mole Mapper, an iPhone-based observational study built using the Apple ResearchKit framework. The Mole Mapper app was designed to collect participant-provided images and measurements of moles, together with demographic and behavioral information relating to melanoma risk. The study cohort includes 2,069 participants who contributed 1,920 demographic surveys, 3,274 mole measurements, and 2,422 curated mole images. Survey data recapitulates associations between melanoma and known demographic risks, with red hair as the most significant factor in this cohort. Participant-provided mole measurements indicate an average mole size of 3.95 mm. These data have been made available to engage researchers in a collaborative, multidisciplinary effort to better understand and prevent melanoma.

  11. Identification of Specialists and Abundance-Occupancy Relationships among Intestinal Bacteria of Aves, Mammalia, and Actinopterygii.

    PubMed

    Green, Hyatt C; Fisher, Jenny C; McLellan, Sandra L; Sogin, Mitchell L; Shanks, Orin C

    2015-12-28

    The coalescence of next-generation DNA sequencing methods, ecological perspectives, and bioinformatics analysis tools is rapidly advancing our understanding of the evolution and function of vertebrate-associated bacterial communities. Delineation of host-microbe associations has applied benefits ranging from clinical treatments to protecting our natural waters. Microbial communities follow some broad-scale patterns observed for macroorganisms, but it remains unclear how the specialization of intestinal vertebrate-associated communities to a particular host environment influences broad-scale patterns in microbial abundance and distribution. We analyzed the V6 region of 16S rRNA genes amplified from 106 fecal samples spanning Aves, Mammalia, and Actinopterygii (ray-finned fish). We investigated the interspecific abundance-occupancy relationship, where widespread taxa tend to be more abundant than narrowly distributed taxa, among operational taxonomic units (OTUs) within and among host species. In a separate analysis, we identified specialist OTUs that were highly abundant in a single host and rare in all other hosts by using a multinomial model without excluding undersampled OTUs a priori. We show that intestinal microbes in humans and other vertebrates display abundance-occupancy relationships, but because intestinal host-associated communities have undergone intense specialization, this trend is violated by a disproportionately large number of specialist taxa. Although it is difficult to distinguish the effects of dispersal limitations, host selection, historical contingency, and stochastic processes on community assembly, results suggest that intestinal bacteria can be shared among diverse hosts in ways that resemble the distribution of "free-living" bacteria in the extraintestinal environment.

  12. Feeding mechanics and dietary implications in the fossil sloth Neocnus (Mammalia: Xenarthra: Megalonychidae) from Haiti.

    PubMed

    McAfee, Robert K

    2011-10-01

    Haitian species of the extinct ground sloth genus Neocnus (Mammalia: Pilosa: Megalonychidae) have previously been hypothesized to have a much reduced jugal bone and a correspondingly reduced masseter musculature but a paucity of specimens has prevented further investigation of this hypothesis. Recent discovery of jugal bones belonging to Haitian specimens of Neocnus within the University of Florida Museum collections enables the element to be more accurately described. The discovery also makes it possible to explore mastication in these sloths. Osteological characters related to feeding were examined, along with comparative estimations of bite force with the extant tree sloths, Bradypus and Choloepus, and their known dietary habits as a means to infer aspects of the paleodiet of Neocnus. There is a significant difference in moment arm calculations for m. masseter between predicted and actual jugals, but the overall significance for bite force is lost and hampered by small sample size. Neocnus demonstrates a variety of characters that are similar to those of Bradypus and not to Choloepus, which is a close phylogenetic relative. The masticatory musculature of Neocnus enabled a chewing cycle emphasizing a grinding combination of mesiodistal and linguobuccal movements of the molariform dentition. The orientations of m. masseter and m. temporalis are estimated to produce relatively high bite force ratios that imply a masticatory system with stronger versus faster components. Because of the similarity of bite forces and jaw mechanics to those of Bradypus, in addition to a number of osteological adaptations indicative of herbivorous grazers (elevated mandibular condyle, large and complex masseter, and robust angular process), the Haitian forms of Neocnus are considered to have been selective feeders with a folivorous diet.

  13. Mitochondrial cytochrome b of the Lyakhov mammoth (Proboscidea, Mammalia): new data and phylogenetic analyses of Elephantidae.

    PubMed

    Debruyne, Régis; Barriel, Véronique; Tassy, Pascal

    2003-03-01

    The phylogenetic relationships between recent Elephantidae (Proboscidea, Mammalia), that is to say extant elephants (Asian and African) and extinct woolly mammoth, have remained unclear to date. The prevailing morphological scheme (mammoth grouped with Asian elephant) is either supported or questioned by the molecular results. Recently, the monophyly of woolly mammoths on mitochondrial grounds has been demonstrated (Thomas, et al., 2000), but it conflicts with previous studies (Barriel et al., 1999; Derenko et al., 1997). Here, we report the partial sequencing of two mitochondrial genes: 128 bp of 12S rDNA and 561 bp of cytochrome b for the Lyakhov mammoth, a 49,000-year-old Siberian individual. We use the most comprehensive sample of mammoth (11 sequences) to determine whether the sequences achieved by former studies were congruent or not. The monophyly of a major subset of mammoths sequences (including ours) is recovered. Such a result is assumed to be a good criterion for ascertaining the origin of ancient DNA. Our sequence is incongruent with that of Yang et al. (1996), though obtained for the same individual. As far as the latter sequence is concerned, a contamination by non-identified exogenous DNA is suspected. The robustness and reliability of the sister group relation between Mammuthus primigenius and Loxodonta africana are examined: down-weighting saturated substitutions has no impact on the topology; analyzing data partitions proves that the support of this clade can be assigned to the most conservative phylogenetic signal; insufficient taxonomic and/or characters sampling contributed to former discordant conclusions. We therefore assume the monophyly of "real mammoth sequences" and the (Mammuthus, Loxodonta) clade.

  14. Reproducible Large-Scale Neuroimaging Studies with the OpenMOLE Workflow Management System.

    PubMed

    Passerat-Palmbach, Jonathan; Reuillon, Romain; Leclaire, Mathieu; Makropoulos, Antonios; Robinson, Emma C; Parisot, Sarah; Rueckert, Daniel

    2017-01-01

    OpenMOLE is a scientific workflow engine with a strong emphasis on workload distribution. Workflows are designed using a high level Domain Specific Language (DSL) built on top of Scala. It exposes natural parallelism constructs to easily delegate the workload resulting from a workflow to a wide range of distributed computing environments. OpenMOLE hides the complexity of designing complex experiments thanks to its DSL. Users can embed their own applications and scale their pipelines from a small prototype running on their desktop computer to a large-scale study harnessing distributed computing infrastructures, simply by changing a single line in the pipeline definition. The construction of the pipeline itself is decoupled from the execution context. The high-level DSL abstracts the underlying execution environment, contrary to classic shell-script based pipelines. These two aspects allow pipelines to be shared and studies to be replicated across different computing environments. Workflows can be run as traditional batch pipelines or coupled with OpenMOLE's advanced exploration methods in order to study the behavior of an application, or perform automatic parameter tuning. In this work, we briefly present the strong assets of OpenMOLE and detail recent improvements targeting re-executability of workflows across various Linux platforms. We have tightly coupled OpenMOLE with CARE, a standalone containerization solution that allows re-executing on a Linux host any application that has been packaged on another Linux host previously. The solution is evaluated against a Python-based pipeline involving packages such as scikit-learn as well as binary dependencies. All were packaged and re-executed successfully on various HPC environments, with identical numerical results (here prediction scores) obtained on each environment. Our results show that the pair formed by OpenMOLE and CARE is a reliable solution to generate reproducible results and re-executable pipelines. A

  15. Reproducible Large-Scale Neuroimaging Studies with the OpenMOLE Workflow Management System

    PubMed Central

    Passerat-Palmbach, Jonathan; Reuillon, Romain; Leclaire, Mathieu; Makropoulos, Antonios; Robinson, Emma C.; Parisot, Sarah; Rueckert, Daniel

    2017-01-01

    OpenMOLE is a scientific workflow engine with a strong emphasis on workload distribution. Workflows are designed using a high level Domain Specific Language (DSL) built on top of Scala. It exposes natural parallelism constructs to easily delegate the workload resulting from a workflow to a wide range of distributed computing environments. OpenMOLE hides the complexity of designing complex experiments thanks to its DSL. Users can embed their own applications and scale their pipelines from a small prototype running on their desktop computer to a large-scale study harnessing distributed computing infrastructures, simply by changing a single line in the pipeline definition. The construction of the pipeline itself is decoupled from the execution context. The high-level DSL abstracts the underlying execution environment, contrary to classic shell-script based pipelines. These two aspects allow pipelines to be shared and studies to be replicated across different computing environments. Workflows can be run as traditional batch pipelines or coupled with OpenMOLE's advanced exploration methods in order to study the behavior of an application, or perform automatic parameter tuning. In this work, we briefly present the strong assets of OpenMOLE and detail recent improvements targeting re-executability of workflows across various Linux platforms. We have tightly coupled OpenMOLE with CARE, a standalone containerization solution that allows re-executing on a Linux host any application that has been packaged on another Linux host previously. The solution is evaluated against a Python-based pipeline involving packages such as scikit-learn as well as binary dependencies. All were packaged and re-executed successfully on various HPC environments, with identical numerical results (here prediction scores) obtained on each environment. Our results show that the pair formed by OpenMOLE and CARE is a reliable solution to generate reproducible results and re-executable pipelines. A

  16. Sociality and the telencephalic distribution of corticotrophin-releasing factor, urocortin 3, and binding sites for CRF type 1 and type 2 receptors: A comparative study of eusocial naked mole-rats and solitary Cape mole-rats.

    PubMed

    Coen, Clive W; Kalamatianos, Theodosis; Oosthuizen, Maria K; Poorun, Ravi; Faulkes, Christopher G; Bennett, Nigel C

    2015-11-01

    Various aspects of social behavior are influenced by the highly conserved corticotrophin-releasing factor (CRF) family of peptides and receptors in the mammalian telencephalon. This study has mapped and compared the telencephalic distribution of the CRF receptors, CRF1 and CRF2 , and two of their ligands, CRF and urocortin 3, respectively, in African mole-rat species with diametrically opposed social behavior. Naked mole-rats live in large eusocial colonies that are characterized by exceptional levels of social cohesion, tolerance, and cooperation in burrowing, foraging, defense, and alloparental care for the offspring of the single reproductive female. Cape mole-rats are solitary; they tolerate conspecifics only fleetingly during the breeding season. The telencephalic sites at which the level of CRF1 binding in naked mole-rats exceeds that in Cape mole-rats include the basolateral amygdaloid nucleus, hippocampal CA3 subfield, and dentate gyrus; in contrast, the level is greater in Cape mole-rats in the shell of the nucleus accumbens and medial habenular nucleus. For CRF2 binding, the sites with a greater level in naked mole-rats include the basolateral amygdaloid nucleus and dentate gyrus, but the septohippocampal nucleus, lateral septal nuclei, amygdalostriatal transition area, bed nucleus of the stria terminalis, and medial habenular nucleus display a greater level in Cape mole-rats. The results are discussed with reference to neuroanatomical and behavioral studies of various species, including monogamous and promiscuous voles. By analogy with findings in those species, we speculate that the abundance of CRF1 binding in the nucleus accumbens of Cape mole-rats reflects their lack of affiliative behavior.

  17. This shrew is a jumping mouse (Mammalia, Dipodidae): Sorex dichrurus Rafinesque 1833 is a synonym of Zapus hudsonius (Zimmermann 1780)

    USGS Publications Warehouse

    Woodman, Neal; Carleton, Michael D.

    2012-01-01

    Constantine S. Rafinesque described Sorex dichrurus as a shrew in 1833, based on a specimen he found in a proprietary museum near Niagara Falls on the New York/Ontario border. The name subsequently has been ignored by the scientific community. By describing this specimen as a shrew and ascribing it to the genus Sorex, Rafinesque clearly indicated that his species should be considered a member of the taxonomic family now recognized as the Soricidae (Mammalia, Eulipotyphla). Yet, the description of the animal, and its comparison to ‘‘Gerbillus,’’ clearly identify it as a dipodid rodent, specifically Zapus hudsonius (Zimmermann, 1780); S. dichrurus should be treated as a junior subjective synonym of that taxon. Based on its type locality of Goat Island, New York, this name is also a junior synonym of the subspecies Z. hudsonius canadensis (Davies, 1798).

  18. Moles (Nevi)

    MedlinePlus

    ... Us Media contacts Advertising contacts AAD logo Advertising, marketing and sponsorships Legal notice Copyright © 2017 American Academy ... prohibited without prior written permission. AAD logo Advertising, marketing and sponsorships Legal notice Copyright © 2017 American Academy ...

  19. Hydatidiform mole

    MedlinePlus

    ... egg). It results in an abnormal fetus. The placenta grows normally with little or no growth of ... types: Partial molar pregnancy. There is an abnormal placenta and some fetal development. Complete molar pregnancy. There ...

  20. Atypical Moles

    MedlinePlus

    ... Sections of the JAOCD JAOCD Archive Published Members Online Dermatology Journals Edit This Favorite Name: Category: Share: Yes ... About Tanning 4/24/2013 Sun Safety IQ Online Surveys ... Osteopathic Association. The AOCD now oversees 32 dermatology residency programs that are currently training 163 residents ...

  1. Uterine rupture in twin pregnancy with normal fetus and complete hydatidiform mole.

    PubMed

    Sánchez-Ferrer, María Luisa; Hernández-Martínez, Florentina; Machado-Linde, Francisco; Ferri, Belén; Carbonel, Pablo; Nieto-Diaz, Anibal

    2014-01-01

    We describe a rare case of complete hydatidiform mole with twin live fetus (CHMTF) confirmed by histopathology, flow cytometry and polymerase chain reaction techniques. No malformations were observed, fetal karyotype was normal and β-human chorionic gonadotropin levels were high (>100,000 IU/ml). The patient was informed of the risks and decided to continue with the pregnancy, but at week 15, she had to undergo hysterectomy due to uterine rupture. She subsequently developed persistent trophoblastic disease (PTD) with pulmonary metastases that required treatment with polychemotherapy. Patients with CHMTF should be informed of all known risks, including the considerable risk of PTD, which is similar to or, even higher than that associated with a singleton complete mole. The risk does not appear to be increased by continuing the pregnancy. Because so few series have been published, there is a lack of evidence-based clinical management guidelines. To our knowledge, this is the first report of uterine rupture in CHMTF.

  2. The effects of ultraviolet C radiation on the ultrastructure of the liver cells of mole rats.

    PubMed

    Tekın, Saban; Türker, Hüseyin; Güven, Turan; Yel, Mustafa

    2016-01-01

    The aim of this study was to elucidate the ultrastructural changes in the liver cells of mole rats (Spalax leucodon) exposed to ultraviolet radiation (UVR). Thirteen mole rats used in this study were caught from nature. They were divided into four groups. The first group was separated as a control and was not given any radiation. The rest were exposed to ultraviolet C (UVC) radiation for 7, 14, and 21 days. The electron microscopic examinations revealed that significant ultrastructural changes occurred in the liver tissue. These changes were the reduction in cytoplasmic organelles, dilatation in rough endoplasmic reticulum, impairment of nucleus membrane, and broadened and vacuolated mitochondria in the cytoplasm. Also, UVC radiation caused significant changes in liver enzymes of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and gama-glutamiltransferase values. After long-term exposure to radiation, some excessive ultrastructural changes occurred. These results indicated that longer exposure to UVR would cause more ultrastructural effects on the liver cells and liver enzymes.

  3. Androgen receptor distribution in the social decision-making network of eusocial naked mole-rats.

    PubMed

    Holmes, Melissa M; Van Mil, Spencer; Bulkowski, Camila; Goldman, Sharry L; Goldman, Bruce D; Forger, Nancy G

    2013-11-01

    Naked mole-rats are highly social rodents that live in large groups and exhibit a strict reproductive and social hierarchy. Only a few animals in each colony breed; the remainder are non-reproductive and are socially subordinate to breeders. We have examined androgen receptor immunoreactive (AR+) cells in brain regions comprising the recently described social decision-making network in subordinate and breeder naked mole-rats of both sexes. We find that subordinates have a significantly higher percentage of AR+ cells in all brain regions expressing this protein. By contrast, there were no significant effects of sex and no sex-by-status interactions on the percentage of AR+ cells. Taken together with previous findings, the present data complete a systematic assessment of the distribution of AR protein in the social decision-making network of the eusocial mammalian brain and demonstrate a significant role for social status in the regulation of this protein throughout many nodes of this network.

  4. Geographic dialects in blind mole rats: role of vocal communication in active speciation.

    PubMed Central

    Nevo, E; Heth, G; Beiles, A; Frankenberg, E

    1987-01-01

    We compared and contrasted the physical structure of male "courtship" calls of 59 subterranean mole rats belonging to the Spalax ehrenbergi superspecies in Israel, comprising 11 populations of four chromosomal species (2N = 52, 54, 58, and 60). We also conducted behavioral auditory discrimination tests of 144 females of the four species in the laboratory. The results indicate that each chromosomal species has a vocal dialect significantly different from all others, although the call of 2N = 60, the last derivative of speciation, is not yet fully differentiated. Females of 2N = 52, 54, and 58 preferred their homospecific mates' calls, whereas females of 2N = 60 did not. We conclude that call differentiation builds up gradually and provides an efficient ethological reproductive premating isolation mechanism between the emerging species in the active speciation of mole rats in Israel. PMID:3472211

  5. Seasonal changes in burrow geometry of the common mole rat (Rodentia: Bathyergidae)

    NASA Astrophysics Data System (ADS)

    Thomas, H. G.; Scantlebury, M.; Swanepoel, D.; Bateman, P. W.; Bennett, N. C.

    2013-11-01

    Sociality in mole rats has been suggested to have evolved as a response to the widely dispersed food resources and the limited burrowing opportunities that result from sporadic rainfall events. In the most arid regions, individual foraging efficiency is reduced, and energetic constraints increase. In this study, we investigate seasonal differences in burrow architecture of the social Cryptomys hottentotus hottentotus in a mesic region. We describe burrow geometry in response to seasonal weather conditions for two seasons (wet and dry). Interactions occurred between seasons and colony size for the size of the burrow systems, but not the shape of the burrow systems. The fractal dimension values of the burrow systems did not differ between seasons. Thus, the burrow complexity was dependent upon the number of mole rats present in the social group.

  6. The number of cysteine residues per mole in apolipoprotein E affects systematically synchronous neural interactions in women's healthy brains.

    PubMed

    Leuthold, Arthur C; Mahan, Margaret Y; Stanwyck, John J; Georgopoulos, Angeliki; Georgopoulos, Apostolos P

    2013-05-01

    Apolipoprotein E (apoE) is involved in lipid metabolism in the brain, but its effects on brain function are not understood. Three apoE isoforms (E4, E3, and E2) are the result of cysteine-arginine interchanges at two sites: there are zero interchanges in E4, one interchange in E3, and two interchanges in E2. The resulting six apoE genotypes (E4/4, E4/3, E4/2, E3/3, E3/2, E2/2) yield five groups with respect to the number of cysteine residues per mole (CysR/mole), as follows. ApoE4/4 has zero cysteine residues per mole (0-CysR/mole), E4/3 has one (1-CysR/mole), E4/2 and E3/3 each has two (2-CysR/mole), E3/2 has three (3-CysR/mole), and E2/2 has four (4-CysR/mole). The use of the number of CysR/mole to characterize the apoE molecule converts the categorical apoE genotype scale, consisting of 6 distinct genotypes above, to a 5-point continuous scale (0-4 CysR/mole). This allows the use of statistical analyses suitable for continuous variables (e.g. regression) to quantify the relations between various variables and apoE. Using such analyses, here, we show for the first time that apoE affects in a graded and orderly manner neural communication, as assessed by analyzing the relation between the number of CysR/mole and synchronous neural interactions (SNI) measured by magnetoencephalography (MEG) in 130 cognitively healthy women. At the one end of the CysR/mole range, the 4-CysR/mole (E2/2) SNI distribution had the highest mean, lowest variance, lowest range, and lowest coefficient of variation, whereas at the other end, 0-CysR/mole (E4/4) SNI distribution had the lowest mean, highest variance, highest range, and highest coefficient of variation. The special status of the 4-CysR/mole distribution was reinforced by the results of a hierarchical tree analysis where the 4-CysR/mole (E2/2) SNI distribution occupied a separate branch by itself and the remaining CysR/mole SNI distributions were placed at increasing distances from the 4-CysR/mole distribution, according to

  7. Family Wide Molecular Adaptations to Underground Life in African Mole-Rats Revealed by Phylogenomic Analysis

    PubMed Central

    Davies, Kalina T.J.; Bennett, Nigel C.; Tsagkogeorga, Georgia; Rossiter, Stephen J.; Faulkes, Christopher G.

    2015-01-01

    During their evolutionary radiation, mammals have colonized diverse habitats. Arguably the subterranean niche is the most inhospitable of these, characterized by reduced oxygen, elevated carbon dioxide, absence of light, scarcity of food, and a substrate that is energetically costly to burrow through. Of all lineages to have transitioned to a subterranean niche, African mole-rats are one of the most successful. Much of their ecological success can be attributed to a diet of plant storage organs, which has allowed them to colonize climatically varied habitats across sub-Saharan Africa, and has probably contributed to the evolution of their diverse social systems. Yet despite their many remarkable phenotypic specializations, little is known about molecular adaptations underlying these traits. To address this, we sequenced the transcriptomes of seven mole-rat taxa, including three solitary species, and combined new sequences with existing genomic data sets. Alignments of more than 13,000 protein-coding genes encompassed, for the first time, all six genera and the full spectrum of ecological and social variation in the clade. We detected positive selection within the mole-rat clade and along ancestral branches in approximately 700 genes including loci associated with tumorigenesis, aging, morphological development, and sociality. By combining these results with gene ontology annotation and protein–protein networks, we identified several clusters of functionally related genes. This family wide analysis of molecular evolution in mole-rats has identified a suite of positively selected genes, deepening our understanding of the extreme phenotypic traits exhibited by this group. PMID:26318402

  8. Injectant mole-fraction imaging in compressible mixing flows using planar laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J., Jr.; Abbitt, John D., III; Mcdaniel, James C.

    1989-01-01

    A technique is described for imaging the injectant mole-fraction distribution in nonreacting compressible mixing flow fields. Planar fluorescence from iodine, seeded into air, is induced by a broadband argon-ion laser and collected using an intensified charge-injection-device array camera. The technique eliminates the thermodynamic dependence of the iodine fluorescence in the compressible flow field by taking the ratio of two images collected with identical thermodynamic flow conditions but different iodine seeding conditions.

  9. Raman line imaging for spatially and temporally resolved mole fraction measurements in internal combustion engines.

    PubMed

    Miles, P C

    1999-03-20

    An optical diagnostic system based on line imaging of Raman-scattered light has been developed to study the mixing processes in internal combustion engines. The system permits multipoint, single laser-shot measurements of CO(2), O(2), N(2), C(3)H(8), and H(2)O mole fractions with submillimeter spatial resolution. Selection of appropriate system hardware is discussed, as are subsequent data reduction and analysis procedures. Results are reported for data obtained at multiple crank angles and in two different engine flow fields. Measurements are made at 12 locations simultaneously, each location having measurement volume dimensions of 0.5 mm x 0.5 mm x 0.9 mm. The data are analyzed to obtain statistics of species mole fractions: mean, rms, histograms, and both spatial and cross-species covariance functions. The covariance functions are used to quantify the accuracy of the measured rms mole fraction fluctuations, to determine the integral length scales of the mixture inhomogeneities, and to quantify the cycle-to-cycle fluctuations in bulk mixture composition under well-mixed conditions.

  10. [From human andro- and parthenogenesis (hydatidiform moles and benign ovarian teratomas) to cancer].

    PubMed

    Coullin, P

    2005-01-01

    Genomic imprinting is a process that appeared in mammals. This phenomenon blocks the normal development of parthenogenic and androgenic conceptuses, that is to say benign ovarian teratomas and hydatidiform moles respectively. Pathological modifications of these conceptuses depend on whether the chromosomes come from the mother or father. These pathologies are associated with an accidental anomaly during gametogenesis and/or fertilizing. These reproductive anomalies are sporadic and some familial cases may exist suggesting a genetic control of such diseases. The human andro- and parthenogenetic conceptuses, but more frequently the moles, may be invasive (choriocarcinoma). An imbalance of the imprinting genes may initiate the deregulation of other genes, including oncogenes and anti-oncogenes, which can explain the cancerous modification. Immunological and environmental factors must be also considered (presence of the only paternal chromosomes in the choriocarcinoma). Numerous works on this subject are published and some recent important discoveries underline the roles of genes HOX, Tim P3, E-cad and p-16, and the recurrent chromosome anomalies 7q21+and 8p21- in the mole to choriocarcinoma processing. Although these phenomena are complex and heterogeneous, the andro- and parthenogenote conceptuses are particularly interesting models with which to understand developmental disorders and cancerous progression.

  11. Considerations on future redefinitions of the kilogram, the mole and of other units

    NASA Astrophysics Data System (ADS)

    Becker, P.; DeBièvre, P.; Fujii, K.; Glaeser, M.; Inglis, B.; Luebbig, H.; Mana, G.

    2007-02-01

    The definitions of some units of the Système International are likely to be revised as early as 2011 by basing them on fixed values of fundamental constants of nature, provided experimental realizations are demonstrated with sufficiently small uncertainties. As regards the kilogram, experiments aiming at linking it to the Planck constant and the atomic mass constant are under way in several laboratories. The other units likely to be redefined are the ampere, the kelvin and the mole. We discuss the advantages and disadvantages of different alternatives for revised definitions of the kilogram and the mole. From physical considerations, metrological consequences and ease of understanding, a definition of the kilogram based on the mass of a particle, such as an atom or the electron, is favoured. One of the proposed definitions fixes the value of the Planck constant through the Compton frequency of a material, though unphysical, particle. Finally, a redefinition of the mole, the counting unit of the amount-of-substance, is proposed which fixes the Avogadro constant as a dimensionless number.

  12. Cutaneous and periodontal inputs to the cerebellum of the naked mole-rat (Heterocephalus glaber).

    PubMed

    Sarko, Diana K; Leitch, Duncan B; Catania, Kenneth C

    2013-01-01

    The naked mole-rat (Heterocephalus glaber) is a small fossorial rodent with specialized dentition that is reflected by the large cortical area dedicated to representation of the prominent incisors. Due to naked mole-rats' behavioral reliance on the incisors for digging and for manipulating objects, as well as their ability to move the lower incisors independently, we hypothesized that expanded somatosensory representations of the incisors would be present within the cerebellum in order to accommodate a greater degree of proprioceptive, cutaneous, and periodontal input. Multiunit electrophysiological recordings targeting the ansiform lobule were used to investigate tactile inputs from receptive fields on the entire body with a focus on the incisors. Similar to other rodents, a fractured somatotopy appeared to be present with discrete representations of the same receptive fields repeated within each folium of the cerebellum. These findings confirm the presence of somatosensory inputs to a large area of the naked mole-rat cerebellum with particularly extensive representations of the lower incisors and mystacial vibrissae. We speculate that these extensive inputs facilitate processing of tactile cues as part of a sensorimotor integration network that optimizes how sensory stimuli are acquired through active exploration and in turn adjusts motor outputs (such as independent movement of the lower incisors). These results highlight the diverse sensory specializations and corresponding brain organizational schemes that have evolved in different mammals to facilitate exploration of and interaction with their environment.

  13. Sex, social status, and CRF receptor densities in naked mole-rats.

    PubMed

    Beery, Annaliese K; Bicks, Lucy; Mooney, Skyler J; Goodwin, Nastacia L; Holmes, Melissa M

    2016-02-01

    Naked mole-rats (Heterocephalus glaber) live in groups that are notable for their large size and caste structure, with breeding monopolized by a single female and a small number of males. Recent studies have demonstrated substantial differences between the brains of breeders and subordinates induced by changes in social standing. Corticotropin-releasing factor (CRF) receptors-which bind the hormone CRF as well as related peptides-are important regulators of stress and anxiety, and are emerging as factors affecting social behavior. We conducted autoradiographic analyses of CRF1 and CRF2 receptor binding densities in female and male naked mole-rats varying in breeding status. Both globally and in specific brain regions, CRF1 receptor densities varied with breeding status. CRF1 receptor densities were higher in subordinates across brain regions, and particularly in the piriform cortex and cortical amygdala. Sex differences were present in CRF2 receptor binding densities, as is the case in multiple vole species. CRF2 receptor densities were higher in females, both globally and in the cortical amygdala and lateral amygdalar nucleus. These results provide novel insights into the neurobiology of social hierarchy in naked mole-rats, and add to a growing body of work that links changes in the CRF system with social behavior.

  14. Locomotor Activity and Body Temperature Patterns over a Temperature Gradient in the Highveld Mole-Rat (Cryptomys hottentotus pretoriae).

    PubMed

    Haupt, Meghan; Bennett, Nigel C; Oosthuizen, Maria K

    2017-01-01

    African mole-rats are strictly subterranean mammals that live in extensive burrow systems. High humidity levels in the burrows prevent mole-rats from thermoregulating using evaporative cooling. However, the relatively stable environment of the burrows promotes moderate temperatures and small daily temperature fluctuations. Mole-rats therefore display a relatively wide range of thermoregulation abilities. Some species cannot maintain their body temperatures at a constant level, whereas others employ behavioural thermoregulation. Here we test the effect of ambient temperature on locomotor activity and body temperature, and the relationship between the two parameters, in the highveld mole-rat. We exposed mole-rats to a 12L:12D and a DD light cycle at ambient temperatures of 30°C, 25°C and 20°C while locomotor activity and body temperature were measured simultaneously. In addition, we investigated the endogenous rhythms of locomotor activity and body temperature at different ambient temperatures. Mole-rats displayed nocturnal activity at all three ambient temperatures and were most active at 20°C, but least active at 30°C. Body temperature was highest at 30°C and lowest at 20°C, and the daily cycle was highly correlated with locomotor activity. We show that the mole-rats have endogenous rhythms for both locomotor activity and body temperature. However, the endogenous body temperature rhythm appears to be less robust compared to the locomotor activity rhythm. Female mole-rats appear to be more sensitive to temperature changes than males, increased heterothermy is evident at lower ambient temperatures, whilst males show smaller variation in their body temperatures with changing ambient temperatures. Mole-rats may rely more heavily on behavioural thermoregulation as it is more energy efficient in an already challenging environment.

  15. Locomotor Activity and Body Temperature Patterns over a Temperature Gradient in the Highveld Mole-Rat (Cryptomys hottentotus pretoriae)

    PubMed Central

    Haupt, Meghan; Bennett, Nigel C.

    2017-01-01

    African mole-rats are strictly subterranean mammals that live in extensive burrow systems. High humidity levels in the burrows prevent mole-rats from thermoregulating using evaporative cooling. However, the relatively stable environment of the burrows promotes moderate temperatures and small daily temperature fluctuations. Mole-rats therefore display a relatively wide range of thermoregulation abilities. Some species cannot maintain their body temperatures at a constant level, whereas others employ behavioural thermoregulation. Here we test the effect of ambient temperature on locomotor activity and body temperature, and the relationship between the two parameters, in the highveld mole-rat. We exposed mole-rats to a 12L:12D and a DD light cycle at ambient temperatures of 30°C, 25°C and 20°C while locomotor activity and body temperature were measured simultaneously. In addition, we investigated the endogenous rhythms of locomotor activity and body temperature at different ambient temperatures. Mole-rats displayed nocturnal activity at all three ambient temperatures and were most active at 20°C, but least active at 30°C. Body temperature was highest at 30°C and lowest at 20°C, and the daily cycle was highly correlated with locomotor activity. We show that the mole-rats have endogenous rhythms for both locomotor activity and body temperature. However, the endogenous body temperature rhythm appears to be less robust compared to the locomotor activity rhythm. Female mole-rats appear to be more sensitive to temperature changes than males, increased heterothermy is evident at lower ambient temperatures, whilst males show smaller variation in their body temperatures with changing ambient temperatures. Mole-rats may rely more heavily on behavioural thermoregulation as it is more energy efficient in an already challenging environment. PMID:28072840

  16. Adult neurogenesis in the hedgehog (Erinaceus concolor) and mole (Talpa europaea).

    PubMed

    Bartkowska, K; Turlejski, K; Grabiec, M; Ghazaryan, A; Yavruoyan, E; Djavadian, R L

    2010-01-01

    We investigated adult neurogenesis in two species of mammals belonging to the superorder Laurasiatheria, the southern white-breasted hedgehog (order Erinaceomorpha, species Erinaceus concolor) from Armenia and the European mole (order Soricomorpha, species Talpa europaea) from Poland. Neurogenesis in the brain of these species was examined immunohistochemically, using the endogenous markers doublecortin (DCX) and Ki-67, which are highly conserved among species. We found that in both the hedgehog and mole, like in the majority of earlier investigated mammals, neurogenesis continues in the subventricular zone (SVZ) of the lateral ventricles and in the dentate gyrus (DG). In the DG of both species, DCX-expressing cells and Ki-67-labeled cells were present in the subgranular and granular layers. In the mole, a strong bundle of DCX-labeled processes, presumably axons of granule cells, was observed in the center of the hilus. Proliferating cells (expressing Ki-67) were identified in the SVZ of lateral ventricles of both species, but neuronal precursor cells (expressing DCX) were also observed in the olfactory bulb (OB). In both species, the vast majority of cells expressing DCX in the OB were granule cells with radially orientated dendrites, although some periglomerular cells surrounding the glomeruli were also labeled. In addition, this paper is the first to show DCX-labeled fibers in the anterior commissure of the hedgehog and mole. These fibers must be axons of new neurons making interhemispheric connections between the two OB or piriform (olfactory) cortices. DCX-expressing neurons were observed in the striatum and piriform cortex of both hedgehog and mole. We postulate that in both species a fraction of cells newly generated in the SVZ migrates along the rostral migratory stream to the piriform cortex. This pattern of migration resembles that of the 'second-wave neurons' generated during embryonal development of the neocortex rather than the pattern observed during

  17. Natural infection of Didelphis aurita (Mammalia: Marsupialia) with Leishmania infantum in Brazil

    PubMed Central

    2012-01-01

    hybridization using a L. infantum-specific biotinylated probe. Conclusions In the present paper we present the first report of amastigotes in the tissues of Didelphis aurita (Mammalia: Marsupialia) naturally infected with Leishmania infantum. We also attempt to claim the particular role of some opossum species as hosts of Leishmania infantum, contributing at least in part on the description of potential sylvatic reservoirs. PMID:22676324

  18. Four Cases of Spontaneous Neoplasia in the Naked Mole-Rat (Heterocephalus glaber), A Putative Cancer-Resistant Species.

    PubMed

    Taylor, Kyle R; Milone, Nicholas A; Rodriguez, Carlos E

    2017-01-01

    The naked mole-rat (Heterocephalus glaber) is widely acclaimed to be cancer-resistant and of considerable research interest based on a paucity of reports of neoplasia in this species. We have, however, encountered four spontaneous cases of neoplasia and one presumptive case of neoplasia through routine necropsy and biopsy of individuals in a zoo collection of nonhybrid naked mole-rats bred from a single pair. One case each of metastasizing hepatocellular carcinoma, nephroblastoma (Wilms' tumor), and multicentric lymphosarcoma, as well as presumptive esophageal adenocarcinoma (Barrett's esophagus-like) was identified postmortem among 37 nonautolyzed necropsy submissions of naked mole-rats over 1-year-old that were submitted for necropsy between 1998 and August 2015. One incidental case of cutaneous hemangioma was also identified antemortem by skin biopsy from one naked mole-rat examined for trauma.

  19. Clinical Usefulness of Immunohistochemical Staining of p57kip2 for the Differential Diagnosis of Complete Mole

    PubMed Central

    Sasaki, Shigeru; Sasaki, Yasushi; Kunimura, Toshiaki; Sekizawa, Akihiko; Kojima, Yoshihiro; Iino, Koichi

    2015-01-01

    Objective. Can polymer-based immunohistochemical staining of p57kip2 replace DNA analysis as an inexpensive means of differentiating complete mole from partial mole or hydropic abortion? Methods and Materials. Original paraffin-embedded tissue blocks from 14 equivocal cases were turned over to our laboratory and examined by immunohistochemical staining of p57kip2. Results. Four of the 14 cases showed clearly negative nuclear staining in cytotrophoblasts and villous stromal cells: these results were fully concordant with the control staining. The remaining 10 cases showed apparently positive staining in cytotrophoblasts and villous stromal cells. Without DNA analysis we are able to clearly differentiate the 4 cases of complete mole among the 14 equivocal cases. During follow-up, secondary low-risk gestational trophoblastic neoplasia (GTN) developed in 1 of the 4 cases of complete mole: the GTN was treated by single-agent chemotherapy. No subsequent changes were observed during follow-up in the other cases. Conclusion. Polymer-based immunohistochemical staining of p57kip2 (paternally imprinted gene, expressed from maternal allele) is a very effective method that can be used to differentiate androgenetic complete mole from partial mole and hydropic abortion. We might be able to avoid the cost of DNA analysis. PMID:26161420

  20. Hypofunctional TrkA Accounts for the Absence of Pain Sensitization in the African Naked Mole-Rat.

    PubMed

    Omerbašić, Damir; Smith, Ewan St J; Moroni, Mirko; Homfeld, Johanna; Eigenbrod, Ole; Bennett, Nigel C; Reznick, Jane; Faulkes, Chris G; Selbach, Matthias; Lewin, Gary R

    2016-10-11

    The naked mole-rat is a subterranean rodent lacking several pain behaviors found in humans, rats, and mice. For example, nerve growth factor (NGF), an important mediator of pain sensitization, fails to produce thermal hyperalgesia in naked mole-rats. The sensitization of capsaicin-sensitive TRPV1 ion channels is necessary for NGF-induced hyperalgesia, but naked mole-rats have fully functional TRPV1 channels. We show that exposing isolated naked mole-rat nociceptors to NGF does not sensitize TRPV1. However, the naked mole-rat NGF receptor TrkA displays a reduced ability to engage signal transduction pathways that sensitize TRPV1. Between one- and three-amino-acid substitutions in the kinase domain of the naked mole-rat TrkA are sufficient to render the receptor hypofunctional, and this is associated with the absence of heat hyperalgesia. Our data suggest that evolution has selected for a TrkA variant that abolishes a robust nociceptive behavior in this species but is still compatible with species fitness.

  1. Investigation of the presence and antinociceptive function of muscarinic acetylcholine receptors in the African naked mole-rat (Heterocephalus glaber).

    PubMed

    Jørgensen, Kristine B; Krogh-Jensen, Karen; Pickering, Darryl S; Kanui, Titus I; Abelson, Klas S P

    2016-01-01

    The present study investigated the cholinergic system in the African naked mole-rat (Heterocephalus glaber) with focus on the muscarinic acetylcholine receptor subtypes M1 and M4. The protein sequences for the subtypes m 1-5 of the naked mole-rat were compared to that of the house mouse (Mus musculus) using basic local alignment search tool (BLAST). The presence and function of M1 and M4 was investigated in vivo, using the formalin test with the muscarinic receptor agonists xanomeline and VU0152100. Spinal cord tissue from the naked mole-rat was used for receptor saturation binding studies with [(3)H]-N-methylscopolamine. The BLAST test revealed 95 % protein sequence homology showing the naked mole-rat to have the genetic potential to express all five muscarinic acetylcholine receptor subtypes. A significant reduction in pain behavior was demonstrated after administration of 8.4 mg/kg in the formalin test. Administration of 50 mg/kg VU0152100 resulted in a non-significant tendency towards antinociception. The antinociceptive effects were reversed by the muscarinic acetylcholine receptor antagonist atropine. Binding studies indicated presence of muscarinic acetylcholine receptors with a radioligand affinity comparable to that reported in mice. In conclusion, muscarinic acetylcholine receptor subtypes are present in the naked mole-rat and contribute to antinociception in the naked mole-rat.

  2. Structural, magnetic and microwave properties of barium hexaferrite thick films with different Fe/Ba mole ratio

    NASA Astrophysics Data System (ADS)

    Verma, Samiksha; Dhawan, S. K.; Paesano, Andrea; Pandey, O. P.; Sharma, Puneet

    2015-12-01

    Barium hexaferrite (BaFe12O19) thick films (∼60 μm) with different BaO·xFe2O3 mole ratio (x=5.0-6.0) were prepared by screen printing method. X-ray diffraction analysis confirmed the formation of single phase BaFe12O19 (BaM). Preferential site occupation of Fe3+ ion at five different crystallographic sites, with varied mole ratio was measured by Mössbauer spectroscopy. Vacancy fraction found to be higher at 4f1, 4f2 and 2b sites for mole ratio 5.5 and 5.0 respectively. Magnetic measurement shows that the magnetization (M) and magnetocrystalline anisotropy field (Ha) depends upon mole ratio. M and Ha are found to be maximum for mole ratio 5.5, while the coercivity (Hc) remains constant. Reflection losses (RL) in the frequency range of 12-18 GHz were also studied. Present investigation demonstrates the effect of mole ratio on structural, magnetic and microwave absorption properties of BaM thick films for microwave device applications.

  3. Management of pest mole crickets in Florida and Puerto Rico with a nematode and parasitic wasp

    SciTech Connect

    Leppla, N.C.; Frank, J.H.; Adjei, M.B.; Vicente, N.E.

    2007-03-15

    Non-indigenous invasive mole crickets, Scapteriscus vicinus Scudder (Orthoptera: Gryllotalpidae) in Florida and S. didactylus (Latreille) (the 'changa') in Puerto Rico, are being managed with an entomopathogenic nematode, Steinernema scapterisci (Nguyen and Smart) (Rhabditida: Steinernematidae), and a parasitic wasp, Larra bicolor L. (Hymenoptera: Sphecidae). Pest mole cricket populations have declined by 95% in north central Florida since these specialist natural enemies were released and established in the 1980s. Commercial production of the nematode was initiated, nearly 70 billion were applied in 34 Florida counties, and their establishment, spread, and impact on mole crickets were monitored. The infected mole crickets dispersed the nematode rapidly, so that within 6 months these parasites were present in most of the insects trapped in experimental pastures. Three years later, mole cricket populations were reduced to acceptable levels and the bahiagrass had recovered. The nematode was released for the first time in Puerto Rico during 2001 and has persisted; the wasp was introduced in the late 1930s. The geographical distribution of the wasp is being expanded in Florida and Puerto Rico by planting plots of Spermacoce verticillata (L.), a wildflower indigenous to Puerto Rico and widely distributed in southern Florida. Pastures, sod farms, golf courses, landscapes, and vegetable farms in Florida and Puerto Rico are benefiting from biological control of invasive mole crickets. (author) [Spanish] Los grillotopos invasores no indigenas, Scapteriscus vicinus (Orthoptera: Gryllotalpidae) en el estado de Florida y S. didactylus ('changa') en Puerto Rico, estan siendo manejados por el nematodo entomopathogeno, Steinernema scapterisci (Rhabditida: Steinernematidae) y la avispa parasitica, Larra bicolor (Hymenoptera: Sphecidae). Las poblaciones de los grillotopo plagas han declinado un 95% en el norte central de la Florida desde que estos enemigos naturales especialistas

  4. Social cues elicit sexual behavior in subordinate Damaraland mole-rats independent of gonadal status.

    PubMed

    Carter, Sara N; Goldman, Bruce D; Goldman, Sharry L; Freeman, David A

    2014-01-01

    Damaraland mole-rats (Fukomys damarensis) are among a small number of eusocial mammals. Eusociality is a social system where only a few individuals within a colony engage in direct reproduction, while remaining subordinate members are non-breeders and support reproductive efforts of breeding individuals. Inbreeding avoidance precludes mating between subordinate siblings and between offspring and parents. Interestingly, non-breeders readily attempt to mate with unrelated opposite-sex individuals. This is unusual since the non-breeding females do not attain puberty while in their natal colony. Based on this finding, the present study investigated the role of the gonads in the regulation of mating behaviors in this species and identified the mechanism of inbreeding avoidance. Gonadal-intact and gonadectomized non-breeders from different colonies were removed from their colonies and tested for the expression of sexual behavior. Results indicated that gonadal status had only minor effects on the expression of sexual behavior in either males or females. In a second experiment, sexual behaviors were absent between opposite-sex siblings so long as they had frequent contact with each other; however, following 5 weeks of separation, sexual behavior between these siblings was robustly expressed. Thus, Damaraland mole-rats avoid establishing mating relationships with familiar individuals but will readily mate with unfamiliar individuals of the opposite sex, with genetic relatedness apparently playing little role. The initiation of sexual behavior in Damaraland mole-rats does not require the presence of the gonads, but does require that the members of the pair have not been in contact with one another for at least several weeks.

  5. Genetic Signatures for Enhanced Olfaction in the African Mole-Rats

    PubMed Central

    Stathopoulos, Sofia; Bishop, Jacqueline M.; O’Ryan, Colleen

    2014-01-01

    The Olfactory Receptor (OR) superfamily, the largest in the vertebrate genome, is responsible for vertebrate olfaction and is traditionally subdivided into 17 OR families. Recent studies characterising whole-OR subgenomes revealed a ‘birth and death’ model of evolution for a range of species, however little is known about fine-scale evolutionary dynamics within single-OR families. This study reports the first assessment of fine-scale OR evolution and variation in African mole-rats (Bathyergidae), a family of subterranean rodents endemic to sub-Saharan Africa. Because of the selective pressures of life underground, enhanced olfaction is proposed to be fundamental to the evolutionary success of the Bathyergidae, resulting in a highly diversified OR gene-repertoire. Using a PCR-sequencing approach, we analysed variation in the OR7 family across 14 extant bathyergid species, which revealed enhanced levels of functional polymorphisms concentrated across the receptors’ ligand-binding region. We propose that mole-rats are able to recognise a broad range of odorants and that this diversity is reflected throughout their OR7 gene repertoire. Using both classic tests and tree-based methods to test for signals of selection, we investigate evolutionary forces across the mole-rat OR7 gene tree. Four well-supported clades emerged in the OR phylogeny, with varying signals of selection; from neutrality to positive and purifying selection. Bathyergid life-history traits and environmental niche-specialisation are explored as possible drivers of adaptive OR evolution, emerging as non-exclusive contributors to the positive selection observed at OR7 genes. Our results reveal unexpected complexity of evolutionary mechanisms acting within a single OR family, providing insightful perspectives into OR evolutionary dynamics. PMID:24699281

  6. [Twin pregnancy with complete mole and coexisting fetus: Reach fetal viability is possible].

    PubMed

    Arsène, E; Clouqueur, E; Stichelbout, M; Devisme, L; Vaast, P; Subtil, D

    2015-11-01

    Twin pregnancies combining complete hydatidiform mole and coexistent fetus are a rare situation (incidence in 1/20,000 in 1/100,000 pregnancies) and a challenge for diagnosis. Their complications can be important - bleeding, preeclampsia, miscarriage - and their management remains complex and controversial. In case of continuing the pregnancy, nearly 40% of women have lives babies. Three quarters of fetal loss occur before 24weeks gestation. We report here three new cases; only one of these cases had a favorable outcome.

  7. Mechanisms regulating proteostasis are involved in sympatric speciation of the blind mole rat, Spalax galili.

    PubMed

    Rodriguez, Karl A; Li, Kexin; Nevo, Eviatar; Buffenstein, Rochelle

    2016-01-01

    Genome-wide analysis demonstrates extensive genomic adaptive complexes involved in sympatric speciation between blind mole rats (Spalax galili) in abutting populations living in basalt and chalk soils. Among the gene ontology (GO) enrichment, musculature and metabolism stood out in basalt dwellers while nutrition and neurogenetics were highlighted in chalk residents. Measurements of mechanisms regulating protein homeostasis inspired by these GO terms suggest that at the proteomic level there is also a habitat/soil-type driven divergence with the basalt residents exhibiting higher proteasome activity whereas elevated levels of markers of autophagy are evident in the chalk inhabitants.

  8. Metabolic regulatory clues from the naked mole rat: toward brain regulatory functions during stroke.

    PubMed

    Nathaniel, Thomas I; Otukonyong, Effiong E; Okon, Marvin; Chaves, Jose; Cochran, Thomas; Nathaniel, Adebobola I

    2013-09-01

    Resistance to tissue hypoxia is a robust fundamental adaptation to low oxygen supply, and represents a novel neuroscience problem with significance to mammalian physiology as well as human health. With the underlying mechanisms strongly conserved in evolution, the ability to resist tissue hypoxia in natural systems has recently emerged as an interesting model in mammalian physiology research to understand mechanisms that can be manipulated for the clinical management of stroke. The extraordinary ability to resist tissue hypoxia by the naked mole rat (NMR) indicates the presence of a unique mechanism that underlies the remarkable healthy life span and exceptional hypoxia resistance. This opens an interesting line of research into understanding the mechanisms employed by the naked mole rat (Heterocephalus glaber) to protect the brain during hypoxia. In a series of studies, we first examined the presence of neuroprotection in the brain cells of naked mole rats (NMRs) subjected to hypoxic insults, and then characterized the expression of such neuroprotection in a wide range of time intervals. We used oxygen nutrient deprivation (OND), an in vitro model of resistance to tissue hypoxia to determine whether there is evidence of neuronal survival in the hippocampal (CA1) slices of NMRs that are subjected to chronic hypoxia. Hippocampus neurons of NMRs that were kept in hypoxic condition consistently tolerated OND right from the onset time of 5h. This tolerance was maintained for 24h. This finding indicates that there is evidence of resistance to tissue hypoxia by CA1 neurons of NMRs. We further examined the effect of hypoxia on metabolic rate in the NMR. Repeated measurement of metabolic rates during exposure of naked mole rats to hypoxia over a constant ambient temperature indicates that hypoxia significantly decreased metabolic rates in the NMR, suggesting that the observed decline in metabolic rate during hypoxia may contribute to the adaptive mechanism used by the NMR

  9. Mechanisms regulating proteostasis are involved in sympatric speciation of the blind mole rat, Spalax galili

    PubMed Central

    Rodriguez, Karl A.; Li, Kexin; Nevo, Eviatar; Buffenstein, Rochelle

    2016-01-01

    ABSTRACT Genome-wide analysis demonstrates extensive genomic adaptive complexes involved in sympatric speciation between blind mole rats (Spalax galili) in abutting populations living in basalt and chalk soils. Among the gene ontology (GO) enrichment, musculature and metabolism stood out in basalt dwellers while nutrition and neurogenetics were highlighted in chalk residents. Measurements of mechanisms regulating protein homeostasis inspired by these GO terms suggest that at the proteomic level there is also a habitat/soil-type driven divergence with the basalt residents exhibiting higher proteasome activity whereas elevated levels of markers of autophagy are evident in the chalk inhabitants. PMID:27050459

  10. Absence of histamine-induced itch in the African naked mole-rat and "rescue" by Substance P.

    PubMed

    Smith, Ewan St John; Blass, Gregory R C; Lewin, Gary R; Park, Thomas J

    2010-05-24

    Recent research has proposed a pathway in which sensory neurons expressing the capsaicin activated ion channel TRPV1 are required for histamine-induced itch and subsequent scratching behavior. We examined histamine-induced itch in the African naked mole-rat (Heterocephalus glaber) and found that although naked mole-rats display innate scratching behavior, histamine was unable to evoke increased scratching as is observed in most mouse strains. Using calcium imaging, we examined the histamine sensitivity of naked mole-rat dorsal root ganglia (DRG) neurons and identified a population of small diameter neurons activated by histamine, the majority of which are also capsaicin-sensitive. This suggested that naked mole-rat sensory neurons are activated by histamine, but that spinal dorsal horn processing of sensory information is not the same as in other rodents. We have previously shown that naked mole-rats naturally lack substance P (SP) in cutaneous C-fibers, but that the neurokinin-1 receptor is expressed in the superficial spinal cord. This led us to investigate if SP deficiency plays a role in the lack of histamine-induced scratching in this species. After intrathecal administration of SP into the spinal cord we observed robust scratching behavior in response to histamine injection. Our data therefore support a model in which TRPV1-expressing sensory neurons are important for histamine-induced itch. In addition, we demonstrate a requirement for active, SP-induced post-synaptic drive to enable histamine sensitive afferents to drive itch-related behavior in the naked mole-rat. These results illustrate that it is altered dorsal horn connectivity of nociceptors that underlies the lack of itch and pain-related behavior in the naked mole-rat.

  11. Dominance and queen succession in captive colonies of the eusocial naked mole-rat, Heterocephalus glaber.

    PubMed Central

    Clarke, F M; Faulkes, C G

    1997-01-01

    Naked mole-rat colonies exhibit a high reproductive skew, breeding being typically restricted to one female (the 'queen') and one to three males. Other colony members are reproductively suppressed, although this suppression can be reversed following the removal or death of the queen. We examined dominance and queen succession within captive colonies to investigate the relationship between urinary testosterone and cortisol, dominance rank and reproductive status; and to determine if behavioural and/or physiological parameters can be used as predictors of queen succession. Social structure was characterized by a linear dominance hierarchy before and after queen removal. Prior to queen removal, dominance rank was negatively correlated with body weight and urinary testosterone and cortisol titres in males and females. Queen removal results in social instability and aggression between high ranking individuals. Dominance rank appears to be a good predictor of reproductive status: queens are the highest ranking colony females and are succeeded by the next highest ranking females. The intense dominance-related aggression that accompanies reproductive succession in naked mole-rats provides empirical support for optimal skew theory. PMID:9263466

  12. Adaptations to a subterranean environment and longevity revealed by the analysis of mole rat genomes

    PubMed Central

    Fang, Xiaodong; Seim, Inge; Huang, Zhiyong; Gerashchenko, Maxim V.; Xiong, Zhiqiang; Turanov, Anton A.; Zhu, Yabing; Lobanov, Alexei V.; Fan, Dingding; Yim, Sun Hee; Yao, Xiaoming; Ma, Siming; Yang, Lan; Lee, Sang-Goo; Kim, Eun Bae; Bronson, Roderick T.; Šumbera, Radim; Buffenstein, Rochelle; Zhou, Xin; Krogh, Anders; Park, Thomas J.; Zhang, Guojie; Wang, Jun; Gladyshev, Vadim N.

    2014-01-01

    SUMMARY Subterranean mammals spend their lives in dark, unventilated environments rich in carbon dioxide and ammonia, and low in oxygen. Many of these animals are also long-lived and exhibit reduced aging-associated diseases, such as neurodegenerative disorders and cancer. We sequenced the genome of the Damaraland mole rat (DMR, Fukomys damarensis) and improved the genome assembly of the naked mole rat (NMR, Heterocephalus glaber). Comparative genome analysis, along with transcriptomes of related subterranean rodents, reveal candidate molecular adaptations for subterranean life and longevity, including a divergent insulin peptide, expression of oxygen-carrying globins in the brain, prevention of high CO2-induced pain perception, and enhanced ammonia detoxification. Juxtaposition of the genomes of DMR and other more conventional animals with the genome of NMR revealed several truly exceptional NMR features: unusual thermogenesis, aberrant melatonin system, pain insensitivity, and novel processing of 28S rRNA. Together, the new genomes and transcriptomes extend our understanding of subterranean adaptations, stress resistance and longevity. PMID:25176646

  13. Effects of Freshwater Discharge in Sandy Beach Populations: The Mole Crab Emerita brasiliensis in Uruguay

    NASA Astrophysics Data System (ADS)

    Lercari, D.; Defeo, O.

    1999-10-01

    Sandy beaches are ecosystems which are heavily affected by human activities. An example of this is freshwater discharges, which are known to change salinity, temperature and nutrient regimes and degrade nearshore environments. However, the effects of this kind of disturbance on sandy beach fauna have been little studied. This paper reports the spatial effects of a man-made freshwater canal discharge on the population structure, abundance and reproductive characteristics of the sandy beach mole crab Emerita brasiliensis. Along the 22 km of sandy beach sampled, the mole crab showed a marked longshore variability in population structure and abundance. Abundance of different population components (juveniles, males, females and ovigerous females) significantly decreased towards the canal. Population structure by sex and size, individual weight, fecundity and female maturity patterns at size also displayed a non-linear response to the distance from the freshwater discharge. Only the size structure of males did not follow this pattern. For males, spatial heterogeneity enhanced the detection of density-dependence at less disturbed sites. The authors conclude that artificial freshwater discharges could significantly influence the distribution, abundance and life-history traits of the biota of sandy beaches, and that further study of these ecosystems should include human activities as important factors affecting spatial and temporal trends. The need to consider different spatial and temporal scales in order to detect the effect of anthropogenically-driven impacts in sandy beach populations is stressed.

  14. Structural Features of the Telomerase RNA Gene in the Naked Mole Rat Heterocephalus glaber

    PubMed Central

    Evfratov, S. A.; Smekalova, E. M.; Golovin, A. V.; Logvina, N. A.; Zvereva, M. I.; Dontsova, O. A.

    2014-01-01

    Telomere length, an important feature of life span control, is dependent on the activity of telomerase (a key enzyme of the telomere-length-maintaining system). Telomerase RNA is a component of telomerase and, thus, is crucial for its activity. The structures of telomerase RNA genes and their promoter regions were compared for the long-living naked mole rat and different organisms. Two rare polymorphisms in Heterocephalus glaber telomerase RNA (hgTER) were identified: A→G in the first loop of pseudoknot P2b-p3 (an equivalent of 111nt in hTR) and G→A in the scaRNA domain CR7-p8b (an equivalent of 421nt in hTR). Analysis of TER promoter regions allowed us to identify two new transcription factor binding sites. The first one is the ETS family site, which was found to be a conserved element for all the analyzed TER promoters. The second site is unique for the promoter region of TER of the naked mole rat and is a binding site for the SOX17 transcription factor. The absence of one Sp1 site in the TER promoter region of the naked small rat is an additional specific feature of the promoter area of hgTER. Such variation in the hgTER transcription regulation region and hgTER itself could provide increased telomerase activity in stem cells and an extended lifespan to H. glaber. PMID:25093110

  15. Retinal ganglion cell survival and axon regeneration after optic nerve injury in naked mole-rats.

    PubMed

    Park, Kevin K; Luo, Xueting; Mooney, Skyler J; Yungher, Benjamin J; Belin, Stephane; Wang, Chen; Holmes, Melissa M; He, Zhigang

    2017-02-01

    In the adult mammalian central nervous system (CNS), axonal damage often triggers neuronal cell death and glial activation, with very limited spontaneous axon regeneration. In this study, we performed optic nerve injury in adult naked mole-rats, the longest living rodent, with a maximum life span exceeding 30 years, and found that injury responses in this species are quite distinct from those in other mammalian species. In contrast to what is seen in other mammals, the majority of injured retinal ganglion cells (RGCs) survive with relatively high spontaneous axon regeneration. Furthermore, injured RGCs display activated signal transducer and activator of transcription-3 (STAT3), whereas astrocytes in the optic nerve robustly occupy and fill the lesion area days after injury. These neuron-intrinsic and -extrinsic injury responses are reminiscent of those in "cold-blooded" animals, such as fish and amphibians, suggesting that the naked mole-rat is a powerful model for exploring the mechanisms of neuronal injury responses and axon regeneration in mammals. J. Comp. Neurol. 525:380-388, 2017. © 2016 Wiley Periodicals, Inc.

  16. Differential effects of chronic fluoxetine on the behavior of dominant and subordinate naked mole-rats.

    PubMed

    Mongillo, Daniel L; Kosyachkova, Ekaterina A; Nguyen, Tam M; Holmes, Melissa M

    2014-01-01

    Naked mole-rats are eusocial rodents that live in large subterranean colonies with a strict reproductive and social hierarchy. The breeding female (referred to as the queen) and 1 to 3 breeding males are the only reproductive members of the colony. Breeders are socially dominant and all other colony members are non-reproductive subordinates. The effects of manipulating the serotonergic neurotransmitter system on aggression and dominance behaviors are well studied in many species, but not in eusocial rodents like the naked mole-rat. The current study investigated how the serotonergic system influences aggressive/dominant behaviors in this species. To do this, two separate but related experiments were conducted: the effects of fluoxetine hydrochloride (FLX) on status-specific behaviors of subordinates (Experiment 1) and dominant queens (Experiment 2) were evaluated both in-colony and in a social-pairing paradigm. In accordance with our main hypothesis, chronic treatment of FLX attenuated the frequency and duration of aggression in queens, but not subordinates, when paired with an unfamiliar conspecific. Further exploration of pharmacological manipulation on status-specific behaviors of this eusocial species may elucidate the neurobiological mechanisms underlying their unique and rigid social hierarchy.

  17. Complete Hydatidiform Mole Coexisting with Three Viable Fetuses in a Quadruplet Pregnancy.

    PubMed

    Tariq, Nabia; Ghazali, Usman; Uddin, Zeeshan; Rasheed, Kamran; Tariq, Hina

    2016-04-01

    We hereby report a case of quadruplet pregnancy with delivery of 3 viable infants and a complete mole. This was an induced conception with clomiphene citrate. At 22 weeks, cystic structures were noticed in one of the placentae and a suspicion of co-existant molar pregnancy was made. The case discussed with oncologist and pregnancy was continued with close monitoring of β-hCG and Ultrasound. Her β-hCG at 23 weeks was 748 mIU/ml, which continued to rise until the 29th week of gestation to a level of 305881.68 mIU/ml and declined gradually thereafter. Similarly, hydropic change in placenta also continued to increase progressively. She was given steroid cover at 32 weeks and delivery was aimed at 34 weeks of gestation. The patient went into preterm labour at 33 weeks and 3 female infants delivered by lower segment cesarean section (LSCS) followed by removal of 3 placentae along with copious molar tissue at the end. The newborns were kept in the nursery, non-requiring assisted ventilation and discharged in satisfactory condition. The histopathologyand immunohistochemistry confirmed the diagnosis of a quadruplet pregnancy comprising of one complete mole with 3 normal placentae.

  18. Dasypodidae Borner, 1919 (Insecta, Hymenoptera): Proposed emendation of spelling to Dasypodaidae, so removing the homonymy with Dasypodidae Gray, 1821 (Mammalia, Xenarthra)

    USGS Publications Warehouse

    Alexander, B.A.; Michener, C.D.; Gardner, A.L.

    1998-01-01

    The family-group name DASYPODIDAE Borner, 1919 (Insecta, Hymenoptera) is a junior homonym Of DASYPODIDAE Gray, 1821 (Mammalia, Xenarthra). It is proposed that the homonymy between the two names, which relate to short-tongued bees and armadillos respectively, should be removed by emending the stem of the generic name Dasypoda Latreille, 1802, on which the insect familygroup name is based, to give DASYPODAIDAE, while leaving the mammalian name (based on Dasypus Linnaeus, 1758) unchanged. Dasypus novemcinctus Linnaeus, 1758, the type species of Dasypus, has a wide distribution in the southern United States, Central and South America. The genus Dasypoda ranges throughout most of the Palearctic region.

  19. Community structure variability of Uropodina mites (Acari: Mesostigmata) in nests of the common mole, Talpa europaea, in Central Europe.

    PubMed

    Napierała, Agnieszka; Mądra, Anna; Leszczyńska-Deja, Kornelia; Gwiazdowicz, Dariusz J; Gołdyn, Bartłomiej; Błoszyk, Jerzy

    2016-04-01

    Underground nests of Talpa europaea, known as the common mole, are very specific microhabitats, which are also quite often inhabited by various groups of arthropods. Mites from the suborder Uropodina (Acari: Mesostigmata) are only one of them. One could expect that mole nests that are closely located are inhabited by communities of arthropods with similar species composition and structure. However, results of empirical studies clearly show that even nests which are close to each other can be different both in terms of the species composition and abundance of Uropodina communities. So far, little is known about the factors that can cause these differences. The major aim of this study was to identify factors determining species composition, abundance, and community structure of Uropodina communities in mole nests. The study is based on material collected during a long-term investigation conducted in western parts of Poland. The results indicate that the two most important factors influencing species composition and abundance of Uropodina communities in mole nests are nest-building material and depth at which nests are located. Composition of Uropodina communities in nests of moles was also compared with that of other microhabitats (e.g. rotten wood, forest litter, soil) based on data from 4421 samples collected in Poland. Communities of this habitat prove most similar to these of open areas, especially meadows, as well as some forest types.

  20. Expression pattern of cadherins in the naked mole rat (Heterocephalus glaber) suggests innate cortical diversification of the cerebrum.

    PubMed

    Matsunaga, Eiji; Nambu, Sanae; Iriki, Atsushi; Okanoya, Kazuo

    2011-06-15

    The cerebral cortex is an indispensable region for higher cognitive function that is remarkably diverse among mammalian species. Although previous research has shown that the cortical area map in the mammalian cerebral cortex is formed by innate and activity-dependent mechanisms, it remains unknown how these mechanisms contribute to the evolution and diversification of the functional cortical areas in various species. The naked mole rat (Heterocephalus glaber) is a subterranean, eusocial rodent. Physiological and anatomical studies have revealed that the visual system is regressed and the somatosensory system is enlarged. To examine whether species differences in cortical area development are caused by intrinsic factors or environmental factors, we performed comparative gene expression analysis of neonatal naked mole rat and mouse brains. The expression domain of cadherin-6, a somatosensory marker, was expanded caudally and shifted dorsally in the cortex, whereas the expression domain of cadherin-8, a visual marker, was reduced caudally in the neonatal naked mole rat cortex. The expression domain of cadherin-8 was also reduced in other visual areas, such as the lateral geniculate nucleus and superior colliculus. Immunohistochemical analysis of thalamocortical fibers further suggested that somatosensory input did not affect cortical gene expression in the neonatal naked mole rat brain. These results suggest that the development of the somatosensory system and the regression of the visual system in the naked mole rat cortex are due to intrinsic genetic mechanisms as well as sensory input-dependent mechanisms. Intrinsic genetic mechanisms thus appear to contribute to species diversity in cortical area formation.

  1. Effect of hypoxia on metabolic rate, core body temperature, and c-fos expression in the naked mole rat.

    PubMed

    Nathaniel, Thomas I; Otukonyong, Effiong; Abdellatif, Ahmed; Soyinka, Julius O

    2012-10-01

    Recent investigations of hypoxia physiology in the naked mole rat have opened up an interesting line of research into the basic physiological and genomic alterations that accompany hypoxia survival. The extent to which such findings connect the effect of hypoxia to metabolic rate (O₂ consumption), core body temperature (Tb), and transcripts encoding the immediate early gene product (such as c-fos) under a constant ambient temperature (Ta) is not well known. We investigated this issue in the current study. Our first sets of experiments measured Tb and metabolic rates during exposure of naked mole rats to hypoxia over a constant Ta. Hypoxia significantly decreased metabolic rates in the naked mole rat. Although core Tb also decreased during hypoxia, the effect of hypoxia in suppressing core Tb was not significant. The second series of experiments revealed that c-fos protein and mRNA expression in the hippocampus neurons (CA1) increased in naked mole rats that were repeatedly exposed to 3% O₂ for 60 min per day for 5 days when compared to normoxia. Our findings provide evidence for the up-regulation of c-fos and suppression of metabolic rate in hypoxia tolerating naked mole rats under constant ambient temperature. Metabolic suppression and c-fos upregulation constitute part of the physiological complex associated with adaptation to hypoxia.

  2. (H2)2 mole-fraction altitude profile in the atmosphere of Jupiter: A computational study

    NASA Technical Reports Server (NTRS)

    Slanina, Zdenek; Kim, Sang J.; Fox, Kenneth

    1994-01-01

    The mole fraction x(sub 2) of (H2)2 in equilibrium mixture with H2 under the atmospheric conditions of Jupiter is evaluated from the dimerization equilibrium constant calculated by quantum-chemical treatments and also from the Lennard-Jones potential. The treatments are of an ab initio type with the second and fourth order Moller-Plesset perturbation techniques and a basis set superposition error evaluation. The computed dimerization equilibrium constant is combined with observed height profiles of temperature and pressure. In six treatments considered it is found that the mole fraction decreases with increasing height. Various approximations suggest the dimeric mole fraction at the Jupiter 1 atm pressure level between 0.04 and 1.06%.

  3. Heavy metal accumulation in the mole, Talpa europea, and earthworms as an indicator of metal bioavailability in terrestrial environments

    SciTech Connect

    Ma, W.

    1987-12-01

    Bioaccumulation studies in animals can supply valuable information to supplement the data obtained by chemical analysis of pollutants in abiotic samples. With respect to the terrestrial ecosystem, suitable indicator species in the decomposer subsystem can be identified on the basis of functional characteristics and trophic level. Investigations on metal behavior at the first trophic level, done in lumbricid earthworms showed that the potential for bioaccumulation depends on the degree of contamination as well as on the metal-binding capacity of the soil. The present study was performed to investigate metal behavior at a higher trophic level, and the mole (Talpa europea) was chosen a representative of the terrestrial decomposer subsystem. As earthworms are the preferred food of moles, they provide the major source of ingested metals to these animals. The food chain involving earthworms and moles provides an example of a critical pathway for potentially toxic non-essential metals such as cadmium and lead.

  4. Evaluation of germline CDKN2A, ARF, CDK4, PTEN, and BRAF alterations in atypical mole syndrome.

    PubMed

    Celebi, J T; Ward, K M; Wanner, M; Polsky, D; Kopf, A W

    2005-01-01

    Atypical mole syndrome is a sporadic or an inherited condition with an increased risk of melanoma. Germline mutations in the CDKN2A, ARF, CDK4 and somatic mutations in the PTEN and BRAF genes have been associated with melanoma. In this study, we evaluated genes associated with familial and sporadic melanoma for mutations in 28 probands with the atypical mole syndrome. No sequence alterations in the coding regions or in the splice junctions of CDKN2A, ARF, CDK4, PTEN or BRAF were identified. These data suggest that genes evaluated in this study are unlikely to be candidate genes for atypical mole syndrome and support the notion that unknown susceptibility gene/s for this disease exist.

  5. Descriptive study of the diaphragm and lungs in the short-nosed echidna, Tachyglossus aculeatus (Mammalia: monotremata).

    PubMed

    Perry, S F; Schmitz, A; Andersen, N A; Wallau, B R; Nicol, S

    2000-03-01

    In this descriptive study, we characterize the diaphragm and lungs of the short-nosed echidna, Tachyglossus aculeatus, using a combination of gross anatomical, light-microscopic, electron microscopic, and morphometric techniques, including airway casting. The diaphragm is inclined from ventro-cranial to dorso-caudal and possesses a large central tendon (centrum tendineum). The crural and costal muscle groups and the associated trigoni are located in the same positions as in other mammals. The bronchial branching pattern reveals cranially broad, tapering stem bronchi and an unusually small number of first order bronchi. The asymmetrical primary branching pattern and possibly also the asymmetry of right and left lungs are plesiomorphic within the Mammalia. The histology and ultrastructure of the airways and lung parenchyma reveal no unusual features: alveolar type 1 and type 2 cells in the parenchyma; type 2 cells, exocrine bronchiolar cells (Clara cells), ciliated cells, and goblet cells in the terminal airways and the latter two cell types in the bronchi. Both a double and a single capillary net are found on the interalveolar septa. The high capillary loading of the double net may be of selective advantage because of long apneas and low metabolic rate in the echidna.

  6. A mongoose remain (Mammalia: Carnivora) from the Upper Irrawaddy sediments, Myanmar and its significance in evolutionary history of Asian herpestids

    NASA Astrophysics Data System (ADS)

    Egi, Naoko; Thaung-Htike; Zin-Maung-Maung-Thein; Maung-Maung; Nishioka, Yuichiro; Tsubamoto, Takehisa; Ogino, Shintaro; Takai, Masanaru

    2011-11-01

    A tooth of a mongoose (Mammalia: Carnivora: Herpestidae) was discovered from the Upper Irrawaddy sediments in central Myanmar. The age of the fauna is not older than the mid-Pliocene. It is identified as a right first upper molar of a small species of Urva (formally included in the genus Herpestes) based on its size and shape. The present specimen is the first carnivoran from the Upper Irrawaddy sediments and is the first record of mongooses in the Pliocene and early Pleistocene of Asia. It confirms that mongooses had already dispersed into Southeast Asia by the late Pliocene, being consistent with the previous molecular phylogenetic analyses. The fossil may belong to one of the extant species, but an assignment to a specific species is difficult due to the fragmentary nature of the specimen and the small interspecific differences in dental shape among the Asian mongooses. The size of the tooth suggests that the Irrawaddy specimen is within or close to the clade of Urva auropunctata + javanica + edwardsii, and this taxonomic assignment agrees with the geographical distribution.

  7. Functional skeletal morphology and its implications for locomotory behavior among three genera of myosoricine shrews (Mammalia: Eulipotyphla: Soricidae)

    USGS Publications Warehouse

    Woodman, Neal; Stabile, Frank A.

    2015-01-01

    Myosoricinae is a small clade of shrews (Mammalia, Eulipotyphla, Soricidae) that is currently restricted to the African continent. Individual species have limited distributions that are often associated with higher elevations. Although the majority of species in the subfamily are considered ambulatory in their locomotory behavior, species of the myosoricine genus Surdisorex are known to be semifossorial. To better characterize variation in locomotory behaviors among myosoricines, we calculated 32 morphological indices from skeletal measurements from nine species representing all three genera that comprise the subfamily (i.e., Congosorex, Myosorex, Surdisorex) and compared them to indices calculated for two species with well-documented locomotory behaviors: the ambulatory talpid Uropsilus soricipes and the semifossorial talpid Neurotrichus gibbsii. We summarized the 22 most complete morphological variables by 1) calculating a mean percentile rank for each species and 2) using the first principal component from principal component analysis of the indices. The two methods yielded similar results and indicate grades of adaptations reflecting a range of potential locomotory behaviors from ambulatory to semifossorial that exceeds the range represented by the two talpids. Morphological variation reflecting grades of increased semifossoriality among myosoricine shrews is similar in many respects to that seen for soricines, but some features are unique to the Myosoricinae.

  8. A new species of Cryptotis (Mammalia, Eulipotyphla, Soricidae) from the Sierra de Perijá, Venezuelan-Colombian Andes

    USGS Publications Warehouse

    Quiroga-Carmona, Marcial; Woodman, Neal

    2015-01-01

    The Sierra de Perijá is the northern extension of the Cordillera Oriental of the Andes and includes part of the border between Colombia and Venezuela. The population of small-eared shrews (Mammalia, Eulipotyphla, Soricidae, Cryptotis) inhabiting the Sierra de Perijá previously was known from only a single skull from an individual collected in Colombia in 1989. This specimen had been referred to alternatively as C. thomasi and C. meridensis, but more precise definition of the known Colombian and Venezuelan species of Cryptotis has since excluded the Sierra de Perijá population from any named species. The recent collection of a specimen from the Venezuelan slope of Sierra de Perijá, prompted us to re-evaluate the taxonomic status of this population and determine its relationship with other Andean shrews. Our examination of the available specimens revealed that they possess a unique suite of morphological and morphometrical characters, and we describe the Sierra de Perijá population as a new species in the South American C. thomasi species group. Recognition of this new species adds to our knowledge of this genus in South America and to the biodiversity of the Sierra de Perijá.

  9. Comparative analysis of genome maintenance genes in naked mole rat, mouse, and human.

    PubMed

    MacRae, Sheila L; Zhang, Quanwei; Lemetre, Christophe; Seim, Inge; Calder, Robert B; Hoeijmakers, Jan; Suh, Yousin; Gladyshev, Vadim N; Seluanov, Andrei; Gorbunova, Vera; Vijg, Jan; Zhang, Zhengdong D

    2015-04-01

    Genome maintenance (GM) is an essential defense system against aging and cancer, as both are characterized by increased genome instability. Here, we compared the copy number variation and mutation rate of 518 GM-associated genes in the naked mole rat (NMR), mouse, and human genomes. GM genes appeared to be strongly conserved, with copy number variation in only four genes. Interestingly, we found NMR to have a higher copy number of CEBPG, a regulator of DNA repair, and TINF2, a protector of telomere integrity. NMR, as well as human, was also found to have a lower rate of germline nucleotide substitution than the mouse. Together, the data suggest that the long-lived NMR, as well as human, has more robust GM than mouse and identifies new targets for the analysis of the exceptional longevity of the NMR.

  10. A mobile one-sided NMR sensor with a homogeneous magnetic field: the NMR-MOLE.

    PubMed

    Manz, B; Coy, A; Dykstra, R; Eccles, C D; Hunter, M W; Parkinson, B J; Callaghan, P T

    2006-11-01

    A new portable NMR sensor with a novel one-sided access magnet design, termed NMR-MOLE (MObile Lateral Explorer), has been characterised in terms of sensitivity and depth penetration. The magnet has been designed to be portable and create a volume with a relatively homogeneous magnetic field, 15,000 ppm over a region from 4 to 16 mm away from the probe, with maximum sensitivity at a depth of 10 mm. The proton NMR frequency is 3.3 MHz. We have demonstrated that with this approach a highly sensitive, portable, unilateral NMR sensor can be built. Such a design is especially suited for the characterisation of liquids in situations where unilateral or portable access is required.

  11. Fingerprinting: Modelling and mapping physical top soil properties with the Mole

    NASA Astrophysics Data System (ADS)

    Loonstra, Eddie; van Egmond, Fenny

    2010-05-01

    The Mole is a passive gamma ray soil sensor system. It is designed for the mobile collection of radioactive energy stemming from soil. As the system is passive, it only measures energy that reaches the surface of soil. In general, this energy comes from upto 30 to 40 cm deep, which can be considered topsoil. The gathered energy spectra are logged every second, are processed with the method of Full Spectrum Analysis. This method uses all available spectral data and processes it with a Chi square optimalisation using a set of standard spectra into individual nuclide point data. A standard spectrum is the measured full spectrum of a specific detector derived when exposed to 1 Bq/kg of a nuclide. With this method the outcome of the surveys become quantitative.The outcome of a field survey with the Mole results in a data file containing point information of position, Total Counts and the decay products of 232Th, 238U, 40K and 137Cs. Five elements are therefor available for the modelling of soil properties. There are several ways for the modelling of soil properties with sensor derived gamma ray data. The Mole generates ratio scale output. For modelling a quantitative deterministic approach is used based on sample locations. This process is called fingerprinting. Fingerprinting is a comparison of the concentration of the radioactive trace elements and the lab results (pH, clay content, etc.) by regression analysis. This results in a mathematical formula describing the relationship between a dependent and independent property. The results of the sensor readings are interpolated into a nuclide map with GIS software. With the derived formula a soil property map is composed. The principle of fingerprinting can be applied on large geographical areas for physical soil properties such as clay, loam or sand (50 micron), grain size and organic matter. Collected sample data of previous field surveys within the same region can be used for the prediction of soil properties elsewhere

  12. Comparative cytogenetics of moles (Eulipotyphla, Talpidae): chromosomal differences in Talpa romana and T. europaea.

    PubMed

    Gornung, E; Volleth, M; Capanna, E; Castiglia, R

    2008-01-01

    The genus Talpa is the most specious and widespread one in the family Talpidae. The existing karyological records are predominantly basic morphological descriptions. To further investigate the case in point, we performed a comparative cytogenetic study in the genus by comparing G- and C-chromosome banding and NOR patterns of the two European species, T. romana and T. europaea, along with available data regarding several other mole species. Chromosomal hybridization patterns for telomeric repeats and major and 5S ribosomal RNA genes were obtained in T. romana and T. europaea for the first time. The comparison of these patterns revealed differences in distribution of interstitial telomeric repeats and 5S ribosomal RNA genes in the two species with apparently identical karyotypes but different evolutionary histories.

  13. Whack-A-Mole Model: Towards a Unified Description of Biological Effects Caused by Radiation Exposure

    NASA Astrophysics Data System (ADS)

    Manabe, Yuichiro; Wada, Takahiro; Tsunoyama, Yuichi; Nakajima, Hiroo; Nakamura, Issei; Bando, Masako

    2015-04-01

    We present a novel model to for estimating biological effects caused by artificial radiation exposure, i.e., the Whack-A-Mole (WAM) model. It is important to take into account the recovery effects during the time course of cellular reactions. The inclusion of dose-rate dependence is essential in the risk estimation of low-dose radiation, while nearly all the existing theoretical models rely on the total dose dependence only. By analyzing experimental data of the relationship between the radiation dose and the induced mutation frequency of five organisms, namely, mouse, Drosophila, chrysanthemum, maize, Tradescantia, we found that all the data can be reproduced by the WAM model. Most remarkably, a scaling function, which is derived from the WAM model, consistently accounts for the observed mutation frequencies of the five organisms. This is the first rationale to account for the dose rate dependence as well as to provide a unified understanding of a general feature of organisms.

  14. Incidental Finding of Persistent Hydatidiform Mole in an Adolescent on Depo-Provera

    PubMed Central

    McKendrick, Rebecca; Nokkaew, May

    2016-01-01

    Molar pregnancies represent an uncommon yet important obstetric problem with potentially fatal outcomes. Patients typically present with signs and symptoms of early pregnancy, and physicians most often suspect nonmolar pregnancy complications initially; however a hydatidiform mole should be included in the differential diagnosis of a woman with a positive pregnancy test and abnormal vaginal bleeding irrespective of the use of contraception. Our case is that of an adolescent female on Depo-Provera injectable contraceptive with increased vaginal bleeding, abdominal pain, nausea, and vomiting who was incidentally found to be pregnant and subsequently diagnosed with a molar pregnancy despite persistent denial of having initiated sexual intercourse. Though gestational trophoblastic disease is uncommon with an incidence of about 1-2 cases per 1,000 pregnancies, a clinician has to display a high index of suspicion when dealing with patients at extremes of age in order to avoid potentially life-threatening outcomes. PMID:28116190

  15. [Twin pregnancy with a complete hydatiform mole and a viable co-twin].

    PubMed

    Godinho, Ana Beatriz; Martins, Diana; Araújo, Cláudia; Melo, Maria Antonieta; Mendes Graça, Luís

    2014-01-01

    A complete hydatiform mole coexisting with a live, viable twin is a rare event. The diagnosis is challenging, and is normally achieved only at second trimester. It may be associated with thyrotoxicosis, vaginal bleeding, preeclampsia, fetal death or persistent throphoblastic disease. The authors describe the case of a pregnant woman presenting with first trimester bleeding. Ultrasound revealed a twin pregnancy with a viable twin and another placenta apparently detached. At 16 gestational weeks ultrasound revealed a live fetus with a normal placenta and a separate vacuolated and vascularized mass. Facing the hypothesis of gestational trophoblastic disease, the couple chose pregnancy interruption. Given the rarity of this situation, a high index of suspicion is needed to achieve the diagnosis. Despite the existence of case reports with good fetal and maternal outcome, the decision of pregnancy continuation should be made by the informed parents.

  16. On the dimensionality of the Avogadro constant and the definition of the mole

    NASA Astrophysics Data System (ADS)

    Wheatley, Nigel

    2011-06-01

    There is a common misconception among educators, and even some metrologists, that the Avogadro constant NA is (or should be) a pure number, and not a constant of dimension N-1 (where N is the dimension amount of substance). Amount of substance is (and always has been) measured as a ratio of other physical quantities, and not in terms of a specified pure number of elementary entities. Hence the Avogadro constant has always been defined in terms of the unit of amount of substance, and not vice versa. The proposed redefinition of the mole in terms of a fixed value of the Avogadro constant is examined, and it is shown that such a redefinition would not bring any significant metrological benefit. It is contended that such a redefinition would only add to the confusion in this field, and so should be rejected.

  17. Ear Structures of the Naked Mole-Rat, Heterocephalus glaber, and Its Relatives (Rodentia: Bathyergidae)

    PubMed Central

    Mason, Matthew J.; Cornwall, Hannah L.; Smith, Ewan St. J.

    2016-01-01

    Although increasingly popular as a laboratory species, very little is known about the peripheral auditory system of the naked mole-rat, Heterocephalus glaber. In this study, middle and inner ears of naked mole-rats of a range of ages were examined using micro-computed tomography and dissection. The ears of five other bathyergid species (Bathyergus suillus, Cryptomys hottentotus, Fukomys micklemi, Georychus capensis and Heliophobius argenteocinereus) were examined for comparative purposes. The middle ears of bathyergids show features commonly found in other members of the Ctenohystrica rodent clade, including a fused malleus and incus, a synovial stapedio-vestibular articulation and the loss of the stapedius muscle. Heterocephalus deviates morphologically from the other bathyergids examined in that it has a more complex mastoid cavity structure, poorly-ossified processes of the malleus and incus, a ‘columelliform’ stapes and fewer cochlear turns. Bathyergids have semicircular canals with unusually wide diameters relative to their radii of curvature. How the lateral semicircular canal reaches the vestibule differs between species. Heterocephalus has much more limited high-frequency hearing than would be predicted from its small ear structures. The spongy bone forming its ossicular processes, the weak incudo-stapedial articulation, the columelliform stapes and (compared to other bathyergids) reduced cochlear coiling are all potentially degenerate features which might reflect a lack of selective pressure on its peripheral auditory system. Substantial intraspecific differences were found in certain middle and inner ear structures, which might also result from relaxed selective pressures. However, such interpretations must be treated with caution in the absence of experimental evidence. PMID:27926945

  18. EVALUATION OF VIRULENCE OF STEINERNEMA CARPOCAPSAE TO EUROPEAN MOLE CRICKET GRYLLOTALPA GRYLOTALPA L.

    PubMed

    Stefanovska, T; Pisdlisnyuk, V

    2014-01-01

    Common European mole cricket (CEML) Grillotalpa grillotalpa L causes damage to field, vegetable crops, and small fruits growing at commercial plantations and nurseries. Chemical control if insecticides are used in poison bates, soil application or seedling/bulbs treatment is not environmentally friendly. Inundative and innoculative release of CTVL biocontrol agents, in particularly, Entomopathogenic nematode is a reliable alternative to chemical control. At the laboratory study the comparison of the ability of commercial strain (Nemastar) and local Ukrainian isolate of Steinernema carpocapsae in various concentrations to parasite in last instar nymph and adults of G. grillotalpa was investigated. Grillotalpa grillotalpa was found as a susceptible host for both commercial and local strains of S. carpocapsae. The life cycle of S. carpocapsae both strains in the adults of G. grillotapla with concentration 50 IJs per larva has been completed 12-15 days at t=25 C. Two generations of S. carpocapsae were able to develop in mole cricket for both strains. Two strains of S. carpocapsae nematode species tested were pathogenic to adults of G. grillotalpa. The mortalities of G. grillotapla last last instars' larva caused by S. carpocapsae were recorded in every concentration tested at least 20 to 150 IJs per larva. Mean larval mortality ranged from 48% to 95% depending upon nematode strain and rate of application. Larval mortality generally increased with increasing of nematode rates. It was significant for both S. carpocapsae strains (Ukr. Isolate F = 26 > 2,86) and commercial strain (Nemastar F = 102,95 > 2,86). Ukrainian local isolate caused a greater percentage of mortality of G. grillotapla adult than commercial strain of S. carpocapsae tested but interactions between nematode strains, application rates were not significant. This study presents new data on effect of S. carpocapsae isolated for Ukraine to key agricultural polyphagous pest G. grillotalpa susceptibility

  19. Transcriptome, genetic editing, and microRNA divergence substantiate sympatric speciation of blind mole rat, Spalax.

    PubMed

    Li, Kexin; Wang, Liuyang; Knisbacher, Binyamin A; Xu, Qinqin; Levanon, Erez Y; Wang, Huihua; Frenkel-Morgenstern, Milana; Tagore, Satabdi; Fang, Xiaodong; Bazak, Lily; Buchumenski, Ilana; Zhao, Yang; Lövy, Matěj; Li, Xiangfeng; Han, Lijuan; Frenkel, Zeev; Beiles, Avigdor; Cao, Yi Bin; Wang, Zhen Long; Nevo, Eviatar

    2016-07-05

    Incipient sympatric speciation in blind mole rat, Spalax galili, in Israel, caused by sharp ecological divergence of abutting chalk-basalt ecologies, has been proposed previously based on mitochondrial and whole-genome nuclear DNA. Here, we present new evidence, including transcriptome, DNA editing, microRNA, and codon usage, substantiating earlier evidence for adaptive divergence in the abutting chalk and basalt populations. Genetic divergence, based on the previous and new evidence, is ongoing despite restricted gene flow between the two populations. The principal component analysis, neighbor-joining tree, and genetic structure analysis of the transcriptome clearly show the clustered divergent two mole rat populations. Gene-expression level analysis indicates that the population transcriptome divergence is displayed not only by soil divergence but also by sex. Gene ontology enrichment of the differentially expressed genes from the two abutting soil populations highlights reproductive isolation. Alternative splicing variation of the two abutting soil populations displays two distinct splicing patterns. L-shaped FST distribution indicates that the two populations have undergone divergence with gene flow. Transcriptome divergent genes highlight neurogenetics and nutrition characterizing the chalk population, and energetics, metabolism, musculature, and sensory perception characterizing the abutting basalt population. Remarkably, microRNAs also display divergence between the two populations. The GC content is significantly higher in chalk than in basalt, and stress-response genes mostly prefer nonoptimal codons. The multiple lines of evidence of ecological-genomic and genetic divergence highlight that natural selection overrules the gene flow between the two abutting populations, substantiating the sharp ecological chalk-basalt divergence driving sympatric speciation.

  20. Life history plasticity does not confer resilience to environmental change in the mole salamander (Ambystoma talpoideum)

    USGS Publications Warehouse

    Courtney L. Davis,; David A.W. Miller,; Walls, Susan; Barichivich, William J.; Riley, Jeffrey W.; Brown, Mary E.

    2017-01-01

    Plasticity in life history strategies can be advantageous for species that occupy spatially or temporally variable environments. We examined how phenotypic plasticity influences responses of the mole salamander, Ambystoma talpoideum, to disturbance events at the St. Marks National Wildlife Refuge (SMNWR), FL, USA from 2009 to 2014. We observed periods of extensive drought early in the study, in contrast to high rainfall and expansive flooding events in later years. Flooding facilitated colonization of predatory fishes to isolated wetlands across the refuge. We employed multistate occupancy models to determine how this natural experiment influenced the occurrence of aquatic larvae and paedomorphic adults and what implications this may have for the population. We found that, in terms of occurrence, responses to environmental variation differed between larvae and paedomorphs, but plasticity (i.e. the ability to metamorphose rather than remain in aquatic environment) was not sufficient to buffer populations from declining as a result of environmental perturbations. Drought and fish presence negatively influenced occurrence dynamics of larval and paedomorphic mole salamanders and, consequently, contributed to observed short-term declines of this species. Overall occurrence of larval salamanders decreased from 0.611 in 2009 to 0.075 in 2014 and paedomorph occurrence decreased from 0.311 in 2009 to 0.121 in 2014. Although variation in selection pressures has likely maintained this polyphenism previously, our results suggest that continued changes in environmental variability and the persistence of fish in isolated wetlands could lead to a loss of paedomorphosis in the SMNWR population and, ultimately, impact regional persistence in the future.

  1. Middle ear dynamics in response to seismic stimuli in the Cape golden mole (Chrysochloris asiatica).

    PubMed

    Willi, U B; Bronner, G N; Narins, P M

    2006-01-01

    The hypertrophied malleus in the middle ear of some golden moles has been assumed to be an adaptation for sensing substrate vibrations by inertial bone conduction, but this has never been conclusively demonstrated. The Cape golden mole (Chrysochloris asiatica) exhibits this anatomical specialization, and the dynamic properties of its middle ear response to vibrations were the subjects of this study. Detailed three-dimensional middle ear anatomy was obtained by x-ray microcomputed tomography (muCT) at a resolution of 12 microm. The ossicular chain exhibits large malleus mass, selective reduction of stiffness and displacement of the center of mass from the suspension points, all favoring low-frequency tuning of the middle ear response. Orientation of the stapes relative to the ossicular chain and the structure of the stapes footplate enable transmission of substrate vibrations arriving from multiple directions to the inner ear. With the long axes of the mallei aligned parallel to the surface, the animal's head was stimulated by a vibration exciter in the vertical and lateral directions over a frequency range from 10 to 600 Hz. The ossicular chain was shown to respond to both vertical and lateral vibrations. Resonant frequencies were found between 71 and 200 Hz and did not differ significantly between the two stimulation directions. Below resonance, the ossicular chain moves in phase with the skull. Near resonance and above, the malleus moves at a significantly larger mean amplitude (5.8+/-2.8 dB) in response to lateral vs vertical stimuli and is 180 degrees out of phase with the skull in both cases. A concise summary of the propagation characteristics of both seismic body (P-waves) and surface (R-waves) is provided. Potential mechanisms by which the animal might exploit the differential response of the ossicular chain to vertical and lateral excitation are discussed in relation to the properties of surface seismic waves.

  2. Social condition and oxytocin neuron number in the hypothalamus of naked mole-rats (Heterocephalus glaber).

    PubMed

    Mooney, S J; Holmes, M M

    2013-01-29

    The naked mole-rat is a subterranean colonial rodent. In each colony, which can grow to as many as 300 individuals, there is only one female and 1-3 males that are reproductive and socially dominant. The remaining animals are reproductively suppressed subordinates that contribute to colony survival through their cooperative behaviors. Oxytocin is a peptide hormone that has shown relatively widespread effects on prosocial behaviors in other species. We examined whether social status affects the number of oxytocin-immunoreactive neurons in the paraventricular nucleus and the supraoptic nucleus by comparing dominant breeding animals to subordinate non-breeding workers from intact colonies. We also examined these regions in subordinate animals that had been removed from their colony and paired with an opposite- or same-sex conspecific for 6 months. Stereological analyses indicated that subordinates had significantly more oxytocin neurons in the paraventricular nucleus than breeders. Animals in both opposite- and same-sex pairs showed a decreased oxytocin neuron number compared to subordinates suggesting that status differences may be due to social condition rather than the reproductive activity of the animal per se. The effects of social status appear to be region specific as no group differences were found for oxytocin neuron number in the supraoptic nucleus. Given that subordinate naked mole-rats are kept reproductively suppressed through antagonism by the queen, we speculate that status differences are due either to oxytocin's anxiolytic properties to combat the stress of this antagonism or to its ability to promote the prosocial behaviors of subordinates.

  3. Molecular basis of a novel adaptation to hypoxic-hypercapnia in a strictly fossorial mole

    PubMed Central

    2010-01-01

    Background Elevated blood O2 affinity enhances survival at low O2 pressures, and is perhaps the best known and most broadly accepted evolutionary adjustment of terrestrial vertebrates to environmental hypoxia. This phenotype arises by increasing the intrinsic O2 affinity of the hemoglobin (Hb) molecule, by decreasing the intracellular concentration of allosteric effectors (e.g., 2,3-diphosphoglycerate; DPG), or by suppressing the sensitivity of Hb to these physiological cofactors. Results Here we report that strictly fossorial eastern moles (Scalopus aquaticus) have evolved a low O2 affinity, DPG-insensitive Hb - contrary to expectations for a mammalian species that is adapted to the chronic hypoxia and hypercapnia of subterranean burrow systems. Molecular modelling indicates that this functional shift is principally attributable to a single charge altering amino acid substitution in the β-type δ-globin chain (δ136Gly→Glu) of this species that perturbs electrostatic interactions between the dimer subunits via formation of an intra-chain salt-bridge with δ82Lys. However, this replacement also abolishes key binding sites for the red blood cell effectors Cl-, lactate and DPG (the latter of which is virtually absent from the red cells of this species) at δ82Lys, thereby markedly reducing competition for carbamate formation (CO2 binding) at the δ-chain N-termini. Conclusions We propose this Hb phenotype illustrates a novel mechanism for adaptively elevating the CO2 carrying capacity of eastern mole blood during burst tunnelling activities associated with subterranean habitation. PMID:20637064

  4. Life history plasticity does not confer resilience to environmental change in the mole salamander (Ambystoma talpoideum).

    PubMed

    Davis, Courtney L; Miller, David A W; Walls, Susan C; Barichivich, William J; Riley, Jeffrey; Brown, Mary E

    2017-03-01

    Plasticity in life history strategies can be advantageous for species that occupy spatially or temporally variable environments. We examined how phenotypic plasticity influences responses of the mole salamander, Ambystoma talpoideum, to disturbance events at the St. Marks National Wildlife Refuge (SMNWR), FL, USA from 2009 to 2014. We observed periods of extensive drought early in the study, in contrast to high rainfall and expansive flooding events in later years. Flooding facilitated colonization of predatory fishes to isolated wetlands across the refuge. We employed multistate occupancy models to determine how this natural experiment influenced the occurrence of aquatic larvae and paedomorphic adults and what implications this may have for the population. We found that, in terms of occurrence, responses to environmental variation differed between larvae and paedomorphs, but plasticity (i.e. the ability to metamorphose rather than remain in aquatic environment) was not sufficient to buffer populations from declining as a result of environmental perturbations. Drought and fish presence negatively influenced occurrence dynamics of larval and paedomorphic mole salamanders and, consequently, contributed to observed short-term declines of this species. Overall occurrence of larval salamanders decreased from 0.611 in 2009 to 0.075 in 2014 and paedomorph occurrence decreased from 0.311 in 2009 to 0.121 in 2014. Although variation in selection pressures has likely maintained this polyphenism previously, our results suggest that continued changes in environmental variability and the persistence of fish in isolated wetlands could lead to a loss of paedomorphosis in the SMNWR population and, ultimately, impact regional persistence in the future.

  5. Transcriptome, genetic editing, and microRNA divergence substantiate sympatric speciation of blind mole rat, Spalax

    PubMed Central

    Li, Kexin; Wang, Liuyang; Knisbacher, Binyamin A.; Xu, Qinqin; Levanon, Erez Y.; Wang, Huihua; Frenkel-Morgenstern, Milana; Tagore, Satabdi; Fang, Xiaodong; Bazak, Lily; Buchumenski, Ilana; Zhao, Yang; Lövy, Matěj; Li, Xiangfeng; Han, Lijuan; Frenkel, Zeev; Beiles, Avigdor; Cao, Yi Bin; Wang, Zhen Long; Nevo, Eviatar

    2016-01-01

    Incipient sympatric speciation in blind mole rat, Spalax galili, in Israel, caused by sharp ecological divergence of abutting chalk–basalt ecologies, has been proposed previously based on mitochondrial and whole-genome nuclear DNA. Here, we present new evidence, including transcriptome, DNA editing, microRNA, and codon usage, substantiating earlier evidence for adaptive divergence in the abutting chalk and basalt populations. Genetic divergence, based on the previous and new evidence, is ongoing despite restricted gene flow between the two populations. The principal component analysis, neighbor-joining tree, and genetic structure analysis of the transcriptome clearly show the clustered divergent two mole rat populations. Gene-expression level analysis indicates that the population transcriptome divergence is displayed not only by soil divergence but also by sex. Gene ontology enrichment of the differentially expressed genes from the two abutting soil populations highlights reproductive isolation. Alternative splicing variation of the two abutting soil populations displays two distinct splicing patterns. L-shaped FST distribution indicates that the two populations have undergone divergence with gene flow. Transcriptome divergent genes highlight neurogenetics and nutrition characterizing the chalk population, and energetics, metabolism, musculature, and sensory perception characterizing the abutting basalt population. Remarkably, microRNAs also display divergence between the two populations. The GC content is significantly higher in chalk than in basalt, and stress-response genes mostly prefer nonoptimal codons. The multiple lines of evidence of ecological–genomic and genetic divergence highlight that natural selection overrules the gene flow between the two abutting populations, substantiating the sharp ecological chalk–basalt divergence driving sympatric speciation. PMID:27339131

  6. A modified mole cricket lure and description of Scapteriscus borellii (Orthoptera: Gryllotalpidae) range expansion and calling song in California.

    PubMed

    Dillman, Adler R; Cronin, Christopher J; Tang, Joseph; Gray, David A; Sternberg, Paul W

    2014-02-01

    Invasive mole cricket species in the genus Scapteriscus have become significant agricultural pests and are continuing to expand their range in North America. Though largely subterranean, adults of some species, such as Scapteriscus borellii Giglio-Tos 1894, are capable of long dispersive flights and phonotaxis to male calling songs to find suitable habitats and mates. Mole crickets in the genus Scapteriscus are known to be attracted to and can be caught by audio lure traps that broadcast synthesized or recorded calling songs. We report improvements in the design and production of electronic controllers for the automation of semipermanent mole cricket trap lures as well as highly portable audio trap collection designs. Using these improved audio lure traps, we collected the first reported individuals of the pest mole cricket S. borellii in California. We describe several characteristic features of the calling song of the California population including that the pulse rate is a function of soil temperature, similar to Florida populations of S. borellii. Further, we show that other calling song characteristics (carrier frequency, intensity, and pulse rate) are significantly different between the populations.

  7. Habitat and Burrow System Characteristics of the Blind Mole Rat Spalax galili in an Area of Supposed Sympatric Speciation

    PubMed Central

    Lövy, Matěj; Šklíba, Jan; Hrouzková, Ema; Dvořáková, Veronika; Nevo, Eviatar; Šumbera, Radim

    2015-01-01

    A costly search for food in subterranean rodents resulted in various adaptations improving their foraging success under given ecological conditions. In Spalax ehrenbergi superspecies, adaptations to local ecological conditions can promote speciation, which was recently supposed to occur even in sympatry at sites where two soil types of contrasting characteristics abut each other. Quantitative description of ecological conditions in such a site has been, nevertheless, missing. We measured characteristics of food supply and soil within 16 home ranges of blind mole rats Spalax galili in an area subdivided into two parts formed by basaltic soil and pale rendzina. We also mapped nine complete mole rat burrow systems to compare burrowing patterns between the soil types. Basaltic soil had a higher food supply and was harder than rendzina even under higher moisture content and lower bulk density. Population density of mole rats was five-times lower in rendzina, possibly due to the lower food supply and higher cover of Sarcopoterium shrubs which seem to be avoided by mole rats. A combination of food supply and soil parameters probably influences burrowing patterns resulting in shorter and more complex burrow systems in basaltic soil. PMID:26192762

  8. A recurrent intragenic genomic duplication, other novel mutations in NLRP7 and imprinting defects in recurrent biparental hydatidiform moles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A complete hydatidiform mole (CHM) is an abnormal pregnancy with hyperproliferative vesicular trophoblast and no fetal development. Most CHM are sporadic and androgenetic, but recurrent HM have biparental inheritance (BiHM) with disrupted DNA methylation at differentially methylated regions (DMRs) o...

  9. A cytosolic protein factor from the naked mole-rat activates proteasomes of other species and protects these from inhibition.

    PubMed

    Rodriguez, Karl A; Osmulski, Pawel A; Pierce, Anson; Weintraub, Susan T; Gaczynska, Maria; Buffenstein, Rochelle

    2014-11-01

    The naked mole-rat maintains robust proteostasis and high levels of proteasome-mediated proteolysis for most of its exceptional (~31years) life span. Here, we report that the highly active proteasome from the naked mole-rat liver resists attenuation by a diverse suite of proteasome-specific small molecule inhibitors. Moreover, mouse, human, and yeast proteasomes exposed to the proteasome-depleted, naked mole-rat cytosolic fractions, recapitulate the observed inhibition resistance, and mammalian proteasomes also show increased activity. Gel filtration coupled with mass spectrometry and atomic force microscopy indicates that these traits are supported by a protein factor that resides in the cytosol. This factor interacts with the proteasome and modulates its activity. Although Heat shock protein 72 kDa (HSP72) and Heat shock protein 40 kDa (Homolog of bacterial DNAJ1) (HSP40(Hdj1)) are among the constituents of this factor, the observed phenomenon, such as increasing peptidase activity and protecting against inhibition cannot be reconciled with any known chaperone functions. This novel function may contribute to the exceptional protein homeostasis in the naked mole-rat and allow it to successfully defy aging.

  10. A Study Comparing the Efficacy of a Mole Ratio Flow Chart to Dimensional Analysis for Teaching Reaction Stoichiometry.

    ERIC Educational Resources Information Center

    Wagner, Eugene P.

    2001-01-01

    Reaction stoichiometry calculations have always been difficult for students. Offers the use of a mole ratio flow chart (MRFC) as a logistical sequence of steps that incorporates molar proportions as alternative problem solving techniques to improve student understanding. Indicates that MRFC users performed as well on exam problems covering…

  11. HP3 on ExoMars - Cutting airbag cloths with the sharp tip of a mechanical mole

    NASA Astrophysics Data System (ADS)

    Krause, C.; Izzo, M.; Re, E.; Mehls, C.; Richter, L.; Coste, P.

    2009-04-01

    The HP3 - Heat Flow and Physical Properties Package - is planned to be one of the Humboldt lander-based instruments on the ESA ExoMars mission. HP3 will allow the measurement of the subsurface temperature gradient and physical as well as thermophysical properties of the subsurface regolith of Mars down to a depth of 5 meters. From these measurements, the planetary heat flux can be inferred. The HP³ instrument package consists of a mole trailing a package of thermal and electrical sensors into the regolith. Beside the payload elements Thermal Excitation and Measurement Suite and a Permittivity Probe the HP3 experiment includes sensors to detect the forward motion and the tilt of the HP3 payload compartment. The HP3 experiment will be integrated into the lander platform of the ExoMars mission. The original accommodation featured a deployment device or a robotic arm to place HP3 onto the soil outside the deflated lander airbags. To avoid adding such deployment devices, it was suggested that the HP3 mole should be capable of piercing the airbags under the lander. The ExoMars lander airbag is made of 4 Kevlar layers (2 abrasive and 2 bladders). A double fold of the airbag (a worst case) would represent a pile of 12 layers. An exploratory study has examined the possibility of piercing airbag cloths by adding sharp cutting blades on the tip of a penetrating mole. In the experimental setup representative layers were laid over a Mars soil simulant. Initial tests used a hammer-driven cutting tip and had moderate to poor results. More representative tests used a prototype of the HP3 mole and were fully successful: the default 4 layer configuration was pierced as well as the 12 layer configuration, the latter one within 3 hours and about 3000 mole strokes This improved behaviour is attributed to the use of representative test hardware where guidance and suppression of mole recoil were concerned. The presentation will provide an explanation of the technical requirements on

  12. Assessing filtering of mountaintop CO2 mole fractions for application to inverse models of biosphere-atmosphere carbon exchange

    NASA Astrophysics Data System (ADS)

    Brooks, B.-G. J.; Desai, A. R.; Stephens, B. B.; Bowling, D. R.; Burns, S. P.; Watt, A. S.; Heck, S. L.; Sweeney, C.

    2012-02-01

    There is a widely recognized need to improve our understanding of biosphere-atmosphere carbon exchanges in areas of complex terrain including the United States Mountain West. CO2 fluxes over mountainous terrain are often difficult to measure due to unusual and complicated influences associated with atmospheric transport. Consequently, deriving regional fluxes in mountain regions with carbon cycle inversion of atmospheric CO2 mole fraction is sensitive to filtering of observations to those that can be represented at the transport model resolution. Using five years of CO2 mole fraction observations from the Regional Atmospheric Continuous CO2 Network in the Rocky Mountains (Rocky RACCOON), five statistical filters are used to investigate a range of approaches for identifying regionally representative CO2 mole fractions. Test results from three filters indicate that subsets based on short-term variance and local CO2 gradients across tower inlet heights retain nine-tenths of the total observations and are able to define representative diel variability and seasonal cycles even for difficult-to-model sites where the influence of local fluxes is much larger than regional mole fraction variations. Test results from two other filters that consider measurements from previous and following days using spline fitting or sliding windows are overly selective. Case study examples showed that these windowing-filters rejected measurements representing synoptic changes in CO2, which suggests that they are not well suited to filtering continental CO2 measurements. We present a novel CO2 lapse rate filter that uses CO2 differences between levels in the model atmosphere to select subsets of site measurements that are representative on model scales. Our new filtering techniques provide guidance for novel approaches to assimilating mountain-top CO2 mole fractions in carbon cycle inverse models.

  13. Expression of acid-sensing ion channels and selection of reference genes in mouse and naked mole rat.

    PubMed

    Schuhmacher, Laura-Nadine; Smith, Ewan St John

    2016-12-13

    Acid-sensing ion channels (ASICs) are a family of ion channels comprised of six subunits encoded by four genes and they are expressed throughout the peripheral and central nervous systems. ASICs have been implicated in a wide range of physiological and pathophysiological processes: pain, breathing, synaptic plasticity and excitotoxicity. Unlike mice and humans, naked mole-rats do not perceive acid as a noxious stimulus, even though their sensory neurons express functional ASICs, likely an adaptation to living in a hypercapnic subterranean environment. Previous studies of ASIC expression in the mammalian nervous system have often not examined all subunits, or have failed to adequately quantify expression between tissues; to date there has been no attempt to determine ASIC expression in the central nervous system of the naked mole-rat. Here we perform a geNorm study to identify reliable housekeeping genes in both mouse and naked mole-rat and then use quantitative real-time PCR to estimate the relative amounts of ASIC transcripts in different tissues of both species. We identify RPL13A (ribosomal protein L13A) and CANX (calnexin), and β-ACTIN and EIF4A (eukaryotic initiation factor 4a) as being the most stably expressed housekeeping genes in mouse and naked mole-rat, respectively. In both species, ASIC3 was most highly expressed in dorsal root ganglia (DRG), and ASIC1a, ASIC2b and ASIC3 were more highly expressed across all brain regions compared to the other subunits. We also show that ASIC4, a proton-insensitive subunit of relatively unknown function, was highly expressed in all mouse tissues apart from DRG and hippocampus, but was by contrast the lowliest expressed ASIC in all naked mole-rat tissues.

  14. Diet is a major factor governing the fecal butyrate-producing community structure across Mammalia, Aves and Reptilia

    PubMed Central

    Vital, Marius; Gao, Jiarong; Rizzo, Mike; Harrison, Tara; Tiedje, James M

    2015-01-01

    Butyrate-producing bacteria have an important role in maintaining host health. They are well studied in human and medically associated animal models; however, much less is known for other Vertebrata. We investigated the butyrate-producing community in hindgut-fermenting Mammalia (n=38), Aves (n=8) and Reptilia (n=8) using a gene-targeted pyrosequencing approach of the terminal genes of the main butyrate-synthesis pathways, namely butyryl-CoA:acetate CoA-transferase (but) and butyrate kinase (buk). Most animals exhibit high gene abundances, and clear diet-specific signatures were detected with but genes significantly enriched in omnivores and herbivores compared with carnivores. But dominated the butyrate-producing community in these two groups, whereas buk was more abundant in many carnivorous animals. Clustering of protein sequences (5% cutoff) of the combined communities (but and buk) placed carnivores apart from other diet groups, except for noncarnivorous Carnivora, which clustered together with carnivores. The majority of clusters (but: 5141 and buk: 2924) did not show close relation to any reference sequences from public databases (identity <90%) demonstrating a large ‘unknown diversity'. Each diet group had abundant signature taxa, where buk genes linked to Clostridium perfringens dominated in carnivores and but genes associated with Ruminococcaceae bacterium D16 were specific for herbivores and omnivores. Whereas 16S rRNA gene analysis showed similar overall patterns, it was unable to reveal communities at the same depth and resolution as the functional gene-targeted approach. This study demonstrates that butyrate producers are abundant across vertebrates exhibiting great functional redundancy and that diet is the primary determinant governing the composition of the butyrate-producing guild. PMID:25343515

  15. Diet is a major factor governing the fecal butyrate-producing community structure across Mammalia, Aves and Reptilia.

    PubMed

    Vital, Marius; Gao, Jiarong; Rizzo, Mike; Harrison, Tara; Tiedje, James M

    2015-03-17

    Butyrate-producing bacteria have an important role in maintaining host health. They are well studied in human and medically associated animal models; however, much less is known for other Vertebrata. We investigated the butyrate-producing community in hindgut-fermenting Mammalia (n = 38), Aves (n = 8) and Reptilia (n = 8) using a gene-targeted pyrosequencing approach of the terminal genes of the main butyrate-synthesis pathways, namely butyryl-CoA:acetate CoA-transferase (but) and butyrate kinase (buk). Most animals exhibit high gene abundances, and clear diet-specific signatures were detected with but genes significantly enriched in omnivores and herbivores compared with carnivores. But dominated the butyrate-producing community in these two groups, whereas buk was more abundant in many carnivorous animals. Clustering of protein sequences (5% cutoff) of the combined communities (but and buk) placed carnivores apart from other diet groups, except for noncarnivorous Carnivora, which clustered together with carnivores. The majority of clusters (but: 5141 and buk: 2924) did not show close relation to any reference sequences from public databases (identity <90%) demonstrating a large 'unknown diversity'. Each diet group had abundant signature taxa, where buk genes linked to Clostridium perfringens dominated in carnivores and but genes associated with Ruminococcaceae bacterium D16 were specific for herbivores and omnivores. Whereas 16S rRNA gene analysis showed similar overall patterns, it was unable to reveal communities at the same depth and resolution as the functional gene-targeted approach. This study demonstrates that butyrate producers are abundant across vertebrates exhibiting great functional redundancy and that diet is the primary determinant governing the composition of the butyrate-producing guild.

  16. Tumour resistance in induced pluripotent stem cells derived from naked mole-rats.

    PubMed

    Miyawaki, Shingo; Kawamura, Yoshimi; Oiwa, Yuki; Shimizu, Atsushi; Hachiya, Tsuyoshi; Bono, Hidemasa; Koya, Ikuko; Okada, Yohei; Kimura, Tokuhiro; Tsuchiya, Yoshihiro; Suzuki, Sadafumi; Onishi, Nobuyuki; Kuzumaki, Naoko; Matsuzaki, Yumi; Narita, Minoru; Ikeda, Eiji; Okanoya, Kazuo; Seino, Ken-Ichiro; Saya, Hideyuki; Okano, Hideyuki; Miura, Kyoko

    2016-05-10

    The naked mole-rat (NMR, Heterocephalus glaber), which is the longest-lived rodent species, exhibits extraordinary resistance to cancer. Here we report that NMR somatic cells exhibit a unique tumour-suppressor response to reprogramming induction. In this study, we generate NMR-induced pluripotent stem cells (NMR-iPSCs) and find that NMR-iPSCs do not exhibit teratoma-forming tumorigenicity due to the species-specific activation of tumour-suppressor alternative reading frame (ARF) and a disruption mutation of the oncogene ES cell-expressed Ras (ERAS). The forced expression of Arf in mouse iPSCs markedly reduces tumorigenicity. Furthermore, we identify an NMR-specific tumour-suppression phenotype-ARF suppression-induced senescence (ASIS)-that may protect iPSCs and somatic cells from ARF suppression and, as a consequence, tumorigenicity. Thus, NMR-specific ARF regulation and the disruption of ERAS regulate tumour resistance in NMR-iPSCs. Our findings obtained from studies of NMR-iPSCs provide new insight into the mechanisms of tumorigenicity in iPSCs and cancer resistance in the NMR.

  17. Macroalgal fouling on the intertidal mole crab Emerita analoga facilitates bird predation

    NASA Astrophysics Data System (ADS)

    Hidalgo, Fernando J.; Firstater, Fausto N.; Lomovasky, Betina J.; Gallegos, Percy; Gamero, Patricia; Iribarne, Oscar O.

    2010-12-01

    In this work, we studied the effects of predation by birds on the intertidal mole crab Emerita analoga fouled by macroalgae in a sandy beach of central Peru (11° S). The epibiosis affected mostly the larger animals, especially adult females. Epibiosis prevalence for the entire intertidal population was relatively low (1-2%), however, within the size range affected by epibiosis in the intertidal zone (18-23 mm in carapace length), 20-38% of the animals were fouled. Focal observations of birds showed that fouled animals are preferred over those non-fouled of the same size class and hence the same sex, being consumed at a higher rate than their proportion in the intertidal (Chesson’s alpha index of prey selection >0.96), and estimations of mortality rates indicated that more than 35% of the intertidal fouled animals are removed everyday by birds. The effect of epibiosis may be mainly attributed to a higher burrowing time or an increased visual attractive effect of the algae, which make fouled animals more conspicuous to predatory birds, or because of fouling enhances profitability of the animals. The results show that epibiosis has negative effects on E. analoga through increasing predation by birds, which in turn restricts the distribution and abundance of fouled E. analoga in the intertidal zone.

  18. Influence of the mole penetrator on measurements of heat flow in lunar subsurface layers

    NASA Astrophysics Data System (ADS)

    Wawrzaszek, Roman; Drogosz, Michal; Seweryn, Karol; Banaszkiewicz, Marek; Grygorczuk, Jerzy

    Measuring the thermal gradient in subsurface layers is a basic method of determination the heat flux from the interior of a planetary body to its surface. In case of the Moon, such measurements complemented with the results of theoretical analysis and modeling can significantly improve our understanding of the thermal and geological evolution of the Moon. In practice, temperature gradient measurements are performed by at least two sensors located at different depths under the surface. These sensors will be attached to a penetrator [1] or to a cable pulled behind the penetrator. In both cases the object that carries the sensors, e.g. penetrator, perturb temperature measurements. In our study we analyze a case of two thermal sensors attached to the ends of 350mm long penetrator made of a composite material. In agreement with the studies of other authors we have found that the penetrator should be placed at the depth of 2-3 meters, where periodic changes of the temperature due to variation of solar flux at the surface are significantly smaller than the error of temperature measurement. The most important result of our analysis is to show how to deconvolve the real gradient of the temperature from the measurements perturbed by the penetrator body. In this way it will be possible to more accurately determine heat flux in the lunar regolith. [1] Grygorczuk J., Seweryn K., Wawrzaszek R., Banaszkiewicz M., Insertion of a Mole Pene-trator -Experimental Results, /39th Lunar and Planetary Science Conference /League City, Texas 2008

  19. The energy costs of sexual dimorphism in mole-rats are morphological not behavioural

    PubMed Central

    Scantlebury, M; Speakman, J.R; Bennett, N.C

    2005-01-01

    Different reproductive strategies of males and females may lead to the evolution of differences in their energetic costs of reproduction, overall energetic requirements and physiological performances. Sexual dimorphism is often associated with costly behaviours (e.g. large males might have a competitive advantage in fighting, which is energetically expensive). However, few studies of mammals have directly compared the energy costs of reproductive activities between sexes. We compared the daily energy expenditure (DEE) and resting metabolic rate (RMR) of males and females of two species of mole-rat, Bathyergus janetta and Georychus capensis (the former is sexually dimorphic in body size and the latter is not) during a period of intense digging when males seek females. We hypothesized that large body size might be indicative of greater digging or fighting capabilities, and hence greater mass-independent DEE values in males of the sexually dimorphic species. In contrast to this prediction, although absolute values of DEE were greater in B. janetta males, mass-independent values were not. No differences were apparent between sexes in G. capensis. By comparison, although RMR values were greater in B. janetta than G. capensis, no differences were apparent between the sexes for either species. The energy cost of dimorphism is most likely to be the cost of maintenance of a large body size, and not the cost of behaviours performed when an individual is large. PMID:16519235

  20. Adaptive methylation regulation of p53 pathway in sympatric speciation of blind mole rats, Spalax.

    PubMed

    Zhao, Yang; Tang, Jia-Wei; Yang, Zhi; Cao, Yi-Bin; Ren, Ji-Long; Ben-Abu, Yuval; Li, Kexin; Chen, Xue-Qun; Du, Ji-Zeng; Nevo, Eviatar

    2016-02-23

    Epigenetic modifications play significant roles in adaptive evolution. The tumor suppressor p53, well known for controlling cell fate and maintaining genomic stability, is much less known as a master gene in environmental adaptation involving methylation modifications. The blind subterranean mole rat Spalax eherenbergi superspecies in Israel consists of four species that speciated peripatrically. Remarkably, the northern Galilee species Spalax galili (2n = 52) underwent adaptive ecological sympatric speciation, caused by the sharply divergent chalk and basalt ecologies. This was demonstrated by mitochondrial and nuclear genomic evidence. Here we show that the expression patterns of the p53 regulatory pathway diversified between the abutting sympatric populations of S. galili in sharply divergent chalk-basalt ecologies. We identified higher methylation on several sites of the p53 promoter in the population living in chalk soil (chalk population). Site mutagenesis showed that methylation on these sites linked to the transcriptional repression of p53 involving Cut-Like Homeobox 1 (Cux1), paired box 4 (Pax 4), Pax 6, and activator protein 1 (AP-1). Diverse expression levels of p53 between the incipiently sympatrically speciating chalk-basalt abutting populations of S. galili selectively affected cell-cycle arrest but not apoptosis. We hypothesize that methylation modification of p53 has adaptively shifted in supervising its target genes during sympatric speciation of S. galili to cope with the contrasting environmental stresses of the abutting divergent chalk-basalt ecologies.

  1. Soboliphyme occidentalis sp. nov. (Nematoda, Soboliphymidae) from the Iberian mole Talpa occidentalis (Insectivora, Talpidae) in Spain.

    PubMed

    Ribas, Alexis; Casanova, Joan Carles

    2004-08-01

    A new species of Soboliphyme from the endemic Iberian mole (Talpa occidentalis) is described. Soboliphyme occidentalis sp. nov. can be readily distinguished from all of its congeners primarily by the position of the vulva, which clearly shows a posterior oesophageal location, and the number of male caudal papillae. S. occidentalis sp. nov. is the only species that has four pairs of caudal papillae. S. abei, S. caucasica and S. jamesoni can be distinguished from S. occidentalis sp. nov. by not having a notched sucker, the anterior position of the vulva and two polar plugs in the eggs. S. jamesoni has an armate oral sucker and longer spicule; S. caucasica a longer spicule and shorter eggs, and S. abei has shorter eggs, which separate these species from S. occidentalis sp. nov. In the rest of the species with a notched oral sucker, S. baturini and S. hirudiniformis are differentiated from S. occidentalis sp. nov. by the anterior position of the vulva, two polar plugs in the egg and the spicule length in S. baturini and S. hirudiniformis and the size of eggs in S. baturini and S. hirudiniformis. S. ataahai, S. soricis and S. urotrichi have the vulva at the oesophago-intestinal junction, 9-10 male caudal papillae (S. ataahai and S. urotrichi), absence of male caudal papillae (S. soricis), armate oral sucker and long spicule in S. ataahai and one row of six circumoral spines in S. urotrichi. A key to the species of Soboliphyme is presented.

  2. Analysis of dental anomalies in the Siberian mole, Talpa altaica (Insectivora, Talpidae).

    PubMed

    Kawada, Shin-ichiro; Koyasu, Kazuhiro; Zholnerovskaya, Elena I; Oda, Sen-ichi

    2006-11-01

    We re-examined tooth variation in specimens of the Siberian mole, Talpa altaica, from the collection of the Siberian Zoological Museum and discuss the mechanisms of dental evolution. The number of teeth counted in 1789 specimens ranged from 34 to 47, and supernumerary, absent, and connate teeth were observed. The most frequent tooth anomaly was an absent tooth in the premolar region (200 maxillary first premolars and 190 mandibular third premolars), which does not support Fujita and Kirino's terminal reduction hypothesis in the mandible [Fujita T, Kirino T. Ha No Kaibougaku. 21st ed. Tokyo: Kanehara Publishers Inc.; 1976 (in Japanese)]. Supernumerary teeth were found in premolar rows and in the incisor and molar regions. An maxillary fourth molar, positioned distal to the normal third molar, was thought to result from a genetically programmed atavistic event during the natal stages. Connate teeth were observed only in the premolar rows and were thought to have developed with the fusion of two independent tooth germs. Connate premolars appeared to result from an expression of an incomplete division of tooth germ at an early developmental stage or a reunion of independent tooth germs, based on the morphological similarity of the normal and supernumerary premolars. These extraordinarily frequent tooth anomalies of T. altaica are of much interest both in terms of tooth development and classification.

  3. Titan's Surface Brightness Temperatures and H2 Mole Fraction from Cassini CIRS

    NASA Technical Reports Server (NTRS)

    Jennings, Donald E.; Flasar, F. M.; Kunde, V. G.; Samuelson, R. E.; Pearl, J. C.; Nixon, C. A.; Carlson, R. C.; Mamoutkine, A. A.; Brasunas, J. C.; Guandique, E.; Achterberg, R. K.; Bjoraker, G. L.; Romani, P. N.; Segura, M. E.; Albright, S. A.; Elliott, M. H.; Tingley, J. S.; Calcutt, S.; Coustenis, A.; Bezard, B.; Courtin, R.

    2008-01-01

    The atmosphere of Titan has a spectral window of low opacity around 530/cm in the thermal infrared where radiation from the surface can be detected from space. The Composite Infrared spectrometer1 (CIRS) uses this window to measure the surface brightness temperature of Titan. By combining all observations from the Cassini tour it is possible to go beyond previous Voyager IRIS studies in latitude mapping of surface temperature. CIRS finds an average equatorial surface brightness temperature of 93.7+/-0.6 K, which is close to the 93.65+/-0.25 K value measured at the surface by Huygens HASi. The temperature decreases toward the poles, reaching 91.6+/-0.7 K at 90 S and 90.0+/-1.0 K at 87 N. The temperature distribution is centered in latitude at approximately 12 S, consistent with Titan's season of late northern winter. Near the equator the temperature varies with longitude and is higher in the trailing hemisphere, where the lower albedo may lead to relatively greater surface heating5. Modeling of radiances at 590/cm constrains the atmospheric H2 mole fraction to 0.12+/-0.06 %, in agreement with results from Voyager iris.

  4. Cryptic sex? Estimates of genome exchange in unisexual mole salamanders (Ambystoma sp.).

    PubMed

    Gibbs, H Lisle; Denton, Robert D

    2016-06-01

    Cryptic sex has been argued to explain the exceptional longevity of certain parthenogenetic vertebrate lineages, yet direct measurements of genetic exchange between sexual and apparently parthenogenetic forms are rare. Female unisexual mole salamanders (Ambystoma sp.) are the oldest known unisexual vertebrate lineage (~5 million years), and one hypothesis for their persistence is that allopolyploid female unisexuals periodically exchange haploid genomes 'genome exchange' during gynogenetic reproduction with males from sympatric sexual species. We test this hypothesis by using genome-specific microsatellite DNA markers to estimate the rates of genome exchange between sexual males and unisexual females in two ponds in NE Ohio. We also test the prediction that levels of gene flow should be higher for 'sympatric' (sexual males present) genomes in unisexuals compared to 'allopatric' (sexual males absent) unisexual genomes. We used a model testing framework in the coalescent-based program MIGRATE-N to compare models where unidirectional gene flow is present and absent between sexual species and unisexuals. As predicted, our results show higher levels of gene flow between sexuals and sympatric unisexual genomes compared to lower (likely artefactual) levels of gene flow between sexuals and allopatric unisexual genomes. Our results provide direct evidence that genome exchange between sexual and unisexual Ambystoma occurs and demonstrate that the magnitude depends on which sexual species are present. The relatively high levels of gene flow suggest that unisexuals must be at a selective advantage over sexual forms so as to avoid extinction due to genetic swamping through genome exchange.

  5. Adaptive methylation regulation of p53 pathway in sympatric speciation of blind mole rats, Spalax

    PubMed Central

    Zhao, Yang; Tang, Jia-Wei; Yang, Zhi; Cao, Yi-Bin; Ren, Ji-Long; Ben-Abu, Yuval; Li, Kexin; Chen, Xue-Qun; Du, Ji-Zeng; Nevo, Eviatar

    2016-01-01

    Epigenetic modifications play significant roles in adaptive evolution. The tumor suppressor p53, well known for controlling cell fate and maintaining genomic stability, is much less known as a master gene in environmental adaptation involving methylation modifications. The blind subterranean mole rat Spalax eherenbergi superspecies in Israel consists of four species that speciated peripatrically. Remarkably, the northern Galilee species Spalax galili (2n = 52) underwent adaptive ecological sympatric speciation, caused by the sharply divergent chalk and basalt ecologies. This was demonstrated by mitochondrial and nuclear genomic evidence. Here we show that the expression patterns of the p53 regulatory pathway diversified between the abutting sympatric populations of S. galili in sharply divergent chalk–basalt ecologies. We identified higher methylation on several sites of the p53 promoter in the population living in chalk soil (chalk population). Site mutagenesis showed that methylation on these sites linked to the transcriptional repression of p53 involving Cut-Like Homeobox 1 (Cux1), paired box 4 (Pax 4), Pax 6, and activator protein 1 (AP-1). Diverse expression levels of p53 between the incipiently sympatrically speciating chalk–basalt abutting populations of S. galili selectively affected cell-cycle arrest but not apoptosis. We hypothesize that methylation modification of p53 has adaptively shifted in supervising its target genes during sympatric speciation of S. galili to cope with the contrasting environmental stresses of the abutting divergent chalk–basalt ecologies. PMID:26858405

  6. Macroscopic anatomy of the lower respiratory system in mole rats (Spalax leucodon).

    PubMed

    İlgun, R; Yoldas, A; Kuru, N; Özkan, Z E

    2014-12-01

    The morphologic and morphometric features of the lower respiratory system in mole rats were examined. It was seen that the low respiratory system of this species leading a special life under highly hypoxic/hypercapnic conditions underground is structurally similar to other mammals living on land in terms of the parts examined; trachea was formed by 29.5 ± 4 oval-formed cartilaginous tracheals arranged backwards and became gradually more stenotic diameter from cranial to the caudal of the neck. The trachea was separated in two principal bronchus at the fourth thoracal intercostal spatium level. The angle between the two main principal bronchi was 60.5 ± 2.35°. The lung constituted 1.29 ± 0.03% of the body weight and the right lung was heavier than the left lung. Fissura inter-lobaris was deep and separated the lung lobes wholly, and the right lung was separated in four lobes, whereas the left lung was not separated into the lobes. Also, the medial lobe of the left lung was the lightest lobe.

  7. Stress, adaptation, and speciation in the evolution of the blind mole rat, Spalax, in Israel.

    PubMed

    Nevo, Eviatar

    2013-02-01

    Environmental stress played a major role in the evolution of the blind mole rat superspecies Spalax ehrenbergi, affecting its adaptive evolution and ecological speciation underground. Spalax is safeguarded all of its life underground from aboveground climatic fluctuations and predators. However, it encounters multiple stresses in its underground burrows including darkness, energetics, hypoxia, hypercapnia, food scarcity, and pathogenicity. Consequently, it evolved adaptive genomic, proteomic, and phenomic complexes to cope with those stresses. Here I describe some of these adaptive complexes, and their theoretical and applied perspectives. Spalax mosaic molecular and organismal evolution involves reductions or regressions coupled with expansions or progressions caused by evolutionary tinkering and natural genetic engineering. Speciation of Spalax in Israel occurred in the Pleistocene, during the last 2.00-2.35 Mya, generating four species associated intimately with four climatic regimes with increasing aridity stress southwards and eastwards representing an ecological speciational adaptive trend: (Spalax golani, 2n=54→S. galili, 2n=52→S. carmeli, 2n=58→S. judaei, 2n=60). Darwinian ecological speciation occurred gradually with relatively little genetic change by Robertsonian chromosomal and genic mutations. Spalax genome sequencing has just been completed. It involves multiple adaptive complexes to life underground and is an evolutionary model to a few hundred underground mammals. It involves great promise in the future for medicine, space flight, and deep-sea diving.

  8. Initial Case Reports of Cancer in Naked Mole-rats (Heterocephalus glaber).

    PubMed

    Delaney, M A; Ward, J M; Walsh, T F; Chinnadurai, S K; Kerns, K; Kinsel, M J; Treuting, P M

    2016-05-01

    Naked mole-rats (NMRs;Heterocephalus glaber) are highly adapted, eusocial rodents renowned for their extreme longevity and resistance to cancer. Because cancer has not been formally described in this species, NMRs have been increasingly utilized as an animal model in aging and cancer research. We previously reported the occurrence of several age-related diseases, including putative pre-neoplastic lesions, in zoo-housed NMR colonies. Here, we report for the first time 2 cases of cancer in zoo-housed NMRs. In Case No. 1, we observed a subcutaneous mass in the axillary region of a 22-year-old male NMR, with histologic, immunohistochemical (pancytokeratin positive, rare p63 immunolabeling, and smooth muscle actin negative), and ultrastructural characteristics of an adenocarcinoma possibly of mammary or salivary origin. In Case No. 2, we observed a densely cellular, poorly demarcated gastric mass of polygonal cells arranged in nests with positive immunolabeling for synaptophysin and chromogranin indicative of a neuroendocrine carcinoma in an approximately 20-year-old male NMR. We also include a brief discussion of other proliferative growths and pre-cancerous lesions diagnosed in 1 zoo colony. Although these case reports do not alter the longstanding observation of cancer resistance, they do raise questions about the scope of cancer resistance and the interpretation of biomedical studies in this model. These reports also highlight the benefit of long-term disease investigations in zoo-housed populations to better understand naturally occurring disease processes in species used as models in biomedical research.

  9. Renal Pathology in a Nontraditional Aging Model: The Naked Mole-Rat (Heterocephalus glaber).

    PubMed

    Delaney, M A; Kinsel, M J; Treuting, P M

    2016-03-01

    The naked mole-rat (NMR; Heterocephalus glaber) is growing in popularity as a model for aging research due to its extreme longevity (up to 30 years), highly adapted physiology, and resistance to cancer, particularly when compared with traditional aging models such as laboratory mice and rats. Despite the NMR's seemingly lengthy health span, several age-related lesions have been documented. During a 15-year retrospective evaluation of a zoo-housed population, histologic changes in the kidneys were reported in 127 of 138 (92%) adult NMRs. Of these, renal tubular mineralization was very common (115 of 127; 90.6%) and found in NMRs without concurrent renal lesions (36 of 127; 28.3%). Many of the other described lesions were considered progressive stages of a single process, generally referred to as chronic nephritis or nephropathy, and diagnosed in 73 of 127 (57.5%), while end-stage renal disease was reported in only 12 (9.4%) NMRs. Renal lesions of these NMRs were comparable to disease entities reported in laboratory rats and certain strains of inbred and noninbred mice. Although many lesions of NMR kidneys were similar to those found in aged laboratory rodents, some common urinary diseases were not represented in the examined colonies. The goal of this study was to describe renal lesions in NMRs from a zoologic setting to familiarize investigators and pathologists with an apparently common and presumably age-related disease in this nontraditional model.

  10. Ectoparasite Burdens of the Damaraland Mole-Rat (Fukomys damarensis) from Southern Africa.

    PubMed

    Lutermann, Heike; Carpenter-Kling, Tegan; Ueckermann, Edward A; Gutjahr, Gundula; Bennett, Nigel C

    2015-12-01

    Damaraland mole-rats (Fukomys damarensis) of the family Bathyergidae are widely distributed subterranean rodents in sub-Saharan Africa. No parasites have ever been reported for this species and only 1 ectoparasite is described for the entire genus. In the current study ectoparasites were collected from individuals captured at 3 localities in South Africa and Namibia to document the ectoparasite community of F. damarensis, investigate their aggregation patterns, and evaluate the influence of season on ectoparasite burden. A total of 2,071 arthropods from 9 mite taxa and 1 louse species (Eulinognathus hilli) were collected from 293 hosts sampled. Of these, 5 mite species (Androlaelaps scapularis, Androlaelaps capensis, Androlaelaps tauffliebi, Radfordia sp., and unidentified chiggers) and the louse were parasites while the remainder was soil mites. All ectoparasites were highly aggregated and the species richness as well as the prevalence and abundance of 4 of them were significantly greater in summer compared to winter, possibly as a result of seasonal changes in rainfall patterns affecting the ectoparasites, host behavior, or both.

  11. Geochemical and Petrologic Constraints on the Source of Eocene Volcanism at Mole Hill, Rockingham County, VA

    NASA Astrophysics Data System (ADS)

    Johnson, E. A.; Beard, J. S.

    2010-12-01

    Mole Hill is an Eocene (48 Ma) basaltic volcanic neck located west of Harrisonburg, VA, and provides a unique opportunity to probe the mantle beneath the Shenandoah Valley. It lies on the northeastern edge of a swarm of alkaline-series volcanic plugs, dikes, and diatremes extending through Rockingham and Highland Counties, VA, and Pendleton County, WV. The Eocene volcanics are thought to have exploited extensive basement fracture systems originally formed during the Alleghenian Orogeny and subsequent rifting. The Eocene volcanism may have been triggered by reactivation of faults due to global shifts in relative plate motions (Southworth 1993, USGS Bull, B1839-I) but the source material and magmatic processes for the Eocene volcanism are largely unknown. Compositional and texture analyses of xenocrystic and groundmass clinopyroxene, olivine, and spinel were completed either at Virginia Tech on the Cameca SX-50 electron microprobe in the Dept of Geological Sciences, or in the Dept of Mineral Sciences, Smithsonian Institution, Washington, D.C using the JEOL JXA-8900R WD/EDS microanalyzer or the FEI NOVA nanoSEM600 FEG Variable Pressure Scanning Electron Microscope. Xenocrysts up to 2cm in diameter are distributed throughout the volcanic neck, with clinopyroxene >>spinel>olivine. The clinopyroxene and olivine xenocrysts show undulatory extinction in cross-polarized light and are found as individual crystals or as aggregates. Clinopyroxene xenocryst cores are high-Al, low-Cr augite ( ˜Wo44En46Fs10) with Mg# 78.5-85.9. The clinopyroxene xenocrysts have compositionally zoned rims 100-250 μm-wide containing abundant plagioclase inclusions and sparse melt inclusions in a sieve texture. The outer edges of xenocrysts approach the compositions of groundmass and microphenocryst clinopyroxenes ( ˜Wo47En38Fs15; Mg# 67.9-74.5). Olivine xenocrysts contain sulfide inclusions and Cr-rich spinel and have Mg-rich ( ˜Fo86-90) cores with more Fe- and Ca-rich rims (Fo70

  12. Local and Regional Scale Genetic Variation in the Cape Dune Mole-Rat, Bathyergus suillus

    PubMed Central

    Visser, Jacobus H.; Bennett, Nigel C.; Jansen van Vuuren, Bettine

    2014-01-01

    The distribution of genetic variation is determined through the interaction of life history, morphology and habitat specificity of a species in conjunction with landscape structure. While numerous studies have investigated this interplay of factors in species inhabiting aquatic, riverine, terrestrial, arboreal and saxicolous systems, the fossorial system has remained largely unexplored. In this study we attempt to elucidate the impacts of a subterranean lifestyle coupled with a heterogeneous landscape on genetic partitioning by using a subterranean mammal species, the Cape dune mole-rat (Bathyergus suillus), as our model. Bathyergus suillus is one of a few mammal species endemic to the Cape Floristic Region (CFR) of the Western Cape of South Africa. Its distribution is fragmented by rivers and mountains; both geographic phenomena that may act as geographical barriers to gene-flow. Using two mitochondrial fragments (cytochrome b and control region) as well as nine microsatellite loci, we determined the phylogeographic structure and gene-flow patterns at two different spatial scales (local and regional). Furthermore, we investigated genetic differentiation between populations and applied Bayesian clustering and assignment approaches to our data. Nearly every population formed a genetically unique entity with significant genetic structure evident across geographic barriers such as rivers (Berg, Verlorenvlei, Breede and Gourits Rivers), mountains (Piketberg and Hottentots Holland Mountains) and with geographic distance at both spatial scales. Surprisingly, B. suillus was found to be paraphyletic with respect to its sister species, B. janetta–a result largely overlooked by previous studies on these taxa. A systematic revision of the genus Bathyergus is therefore necessary. This study provides a valuable insight into how the biology, life-history and habitat specificity of animals inhabiting a fossorial system may act in concert with the structure of the surrounding

  13. Nutrition and burrowing energetics of the Cape mole-rat Georychus capensis.

    PubMed

    Du Toit, J T; Jarvis, J U M; Louw, G N

    1985-04-01

    At 22°C the resting oxygen consumption of G. capensis is 1.13±0.05 cm(3)O2·g(-1)·h(-1) (mean± S.E.). In loose sandy soil the burrowing metabolic rate was approximately three times that of resting (3.41±0.19 cm(3)O2·g(-1)· h(-1)). Rate of oxygen consumption while burrowing bears a linear relationship with rate of burrowing. The equation of the regression line describing this relationship was used to construct a model for calculating energy expenditure of burrowing in free-living mole-rats. The diet of G. capensis consists of some green plant material and geophyte corms. The latter has a mean gross energy content of 16.36 kJ·g(-1) dry weight. The digestibility coefficient for captive G. capensis fed on sweet potato, was 97.42±0.41%. Data collected from an excavated burrow system revealed that the total energetic cost of constructing the burrow amounted to 79% of the estimated digestible energy available from geophyte corms in the area. A food store in the same burrow system was sufficient to meet the maintenance requirements of an adult G. capensis, resting at 22°C, for approximately 80-85 days. Soil samples taken at random adjacent to the burrow contained corms with a mean estimated digestible energy value of 2084 kJ per m(3) of soil. A comparison of energetic cost of burrowing and randomly available digestible energy in the field suggests that foraging patterns are not random.

  14. Evolutionary basis of mitonuclear discordance between sister species of mole salamanders (Ambystoma sp.).

    PubMed

    Denton, Robert D; Kenyon, Laura J; Greenwald, Katherine R; Gibbs, H Lisle

    2014-06-01

    Distinct genetic markers should show similar patterns of differentiation between species reflecting their common evolutionary histories, yet there are increasing examples of differences in the biogeographic distribution of species-specific nuclear (nuDNA) and mitochondrial DNA (mtDNA) variants within and between species. Identifying the evolutionary processes that underlie these anomalous patterns of genetic differentiation is an important goal. Here, we analyse the putative mitonuclear discordance observed between sister species of mole salamanders (Ambystoma barbouri and A. texanum) in which A. barbouri-specific mtDNA is found in animals located within the range of A. texanum. We test three hypotheses for this discordance (undetected range expansion, mtDNA introgression, and hybridization) using nuDNA and mtDNA data analysed with methods that varied in the parameters estimated and the timescales measured. Results from a Bayesian clustering technique (structure), bidirectional estimates of gene flow (migrate-n and IMa2) and phylogeny-based methods (*beast, bucky) all support the conclusion that the discordance is due to geographically restricted mtDNA introgression from A. barbouri into A. texanum. Limited data on species-specific tooth morphology match this conclusion. Significant differences in environmental conditions exist between sites where A. texanum with and without A. barbouri-like mtDNA occur, suggesting a possible role for selection in the process of introgression. Overall, our study provides a general example of the value of using complimentary analyses to make inferences of the directionality, timescale, and source of mtDNA introgression in animals.

  15. Local and regional scale genetic variation in the Cape dune mole-rat, Bathyergus suillus.

    PubMed

    Visser, Jacobus H; Bennett, Nigel C; Jansen van Vuuren, Bettine

    2014-01-01

    The distribution of genetic variation is determined through the interaction of life history, morphology and habitat specificity of a species in conjunction with landscape structure. While numerous studies have investigated this interplay of factors in species inhabiting aquatic, riverine, terrestrial, arboreal and saxicolous systems, the fossorial system has remained largely unexplored. In this study we attempt to elucidate the impacts of a subterranean lifestyle coupled with a heterogeneous landscape on genetic partitioning by using a subterranean mammal species, the Cape dune mole-rat (Bathyergus suillus), as our model. Bathyergus suillus is one of a few mammal species endemic to the Cape Floristic Region (CFR) of the Western Cape of South Africa. Its distribution is fragmented by rivers and mountains; both geographic phenomena that may act as geographical barriers to gene-flow. Using two mitochondrial fragments (cytochrome b and control region) as well as nine microsatellite loci, we determined the phylogeographic structure and gene-flow patterns at two different spatial scales (local and regional). Furthermore, we investigated genetic differentiation between populations and applied Bayesian clustering and assignment approaches to our data. Nearly every population formed a genetically unique entity with significant genetic structure evident across geographic barriers such as rivers (Berg, Verlorenvlei, Breede and Gourits Rivers), mountains (Piketberg and Hottentots Holland Mountains) and with geographic distance at both spatial scales. Surprisingly, B. suillus was found to be paraphyletic with respect to its sister species, B. janetta-a result largely overlooked by previous studies on these taxa. A systematic revision of the genus Bathyergus is therefore necessary. This study provides a valuable insight into how the biology, life-history and habitat specificity of animals inhabiting a fossorial system may act in concert with the structure of the surrounding

  16. Simulation of the shallow groundwater-flow system near Mole Lake, Forest County, Wisconsin

    USGS Publications Warehouse

    Fienen, Michael N.; Juckem, Paul F.; Hunt, Randall J.

    2011-01-01

    The shallow groundwater system near Mole Lake, Forest County, Wis. was simulated using a previously calibrated regional model. The previous model was updated using newly collected water-level measurements and refinements to surface-water features. The updated model was then used to calculate the area contributing recharge for one existing and two proposed pumping locations on lands of the Sokaogon Chippewa Community. Delineated 1-, 5-, and 10-year areas contributing recharge for existing and proposed wells extend from the areas of pumping to the northeast of the pumping locations. Steady-state pumping was simulated for two scenarios: a base pumping scenario using pumping rates that reflect what the Tribe expects to pump and a high pumping scenario, in which the rate was set to the maximum expected from wells installed in this area. In the base pumping scenario, pumping rates of 32 gallons per minute (gal/min; 46,000 gallons per day (gal/d)) from the existing well and 30 gal/min (43,000 gal/d) at each of the two proposed wells were simulated. The high pumping scenario simulated a rate of 70 gal/min (101,000 gal/d) from each of the three pumping wells to estimate of the largest areas contributing recharge that might be expected given what is currently known about the shallow groundwater system. The areas contributing recharge for both the base and high pumping scenarios did not intersect any modeled surface-water bodies; however, the high pumping scenario had a larger areal extent than the base pumping scenario and intersected a septic separator.

  17. RNA sequencing reveals differential expression of mitochondrial and oxidation reduction genes in the long-lived naked mole-rat when compared to mice.

    PubMed

    Yu, Chuanfei; Li, Yang; Holmes, Andrew; Szafranski, Karol; Faulkes, Chris G; Coen, Clive W; Buffenstein, Rochelle; Platzer, Matthias; de Magalhães, João Pedro; Church, George M

    2011-01-01

    The naked mole-rat (Heterocephalus glaber) is a long-lived, cancer resistant rodent and there is a great interest in identifying the adaptations responsible for these and other of its unique traits. We employed RNA sequencing to compare liver gene expression profiles between naked mole-rats and wild-derived mice. Our results indicate that genes associated with oxidoreduction and mitochondria were expressed at higher relative levels in naked mole-rats. The largest effect is nearly 300-fold higher expression of epithelial cell adhesion molecule (Epcam), a tumour-associated protein. Also of interest are the protease inhibitor, alpha2-macroglobulin (A2m), and the mitochondrial complex II subunit Sdhc, both ageing-related genes found strongly over-expressed in the naked mole-rat. These results hint at possible candidates for specifying species differences in ageing and cancer, and in particular suggest complex alterations in mitochondrial and oxidation reduction pathways in the naked mole-rat. Our differential gene expression analysis obviated the need for a reference naked mole-rat genome by employing a combination of Illumina/Solexa and 454 platforms for transcriptome sequencing and assembling transcriptome contigs of the non-sequenced species. Overall, our work provides new research foci and methods for studying the naked mole-rat's fascinating characteristics.

  18. Adult naked mole-rat brain retains the NMDA receptor subunit GluN2D associated with hypoxia tolerance in neonatal mammals.

    PubMed

    Peterson, Bethany L; Park, Thomas J; Larson, John

    2012-01-11

    Adult naked mole-rats show a number of systemic adaptations to a crowded underground habitat that is low in oxygen and high in carbon dioxide. Remarkably, brain slice tissue from adult naked mole-rats also is extremely tolerant to oxygen deprivation as indicated by maintenance of synaptic transmission under hypoxic conditions as well as by a delayed neuronal depolarization during anoxia. These characteristics resemble hypoxia tolerance in brain slices from neonates in a variety of mammal species. An important component of neonatal tolerance to hypoxia involves the subunit composition of NMDA receptors. Neonates have a high proportion of NMDA receptors with GluN2D subunits which are protective because they retard calcium entry into neurons during hypoxic episodes. Therefore, we hypothesized that adult naked mole-rats retain a protective, neonatal-like, NMDA receptor subunit profile. We used immunoblotting to assess age-related changes in NMDA receptor subunits in naked mole-rats and mice. The results show that adult naked mole-rat brain retains a much greater proportion of the hypoxia-protective GluN2D subunit compared to adult mice. However, age-related changes in other subunits (GluN2A and GluN2B) from the neonatal period to adulthood were comparable in mice and naked mole-rats. Hence, adult naked mole-rat brain only retains the neonatal NMDA receptor subunit that is associated with hypoxia tolerance.

  19. Study of Pulse Laser Assisted Metalorganic Vapor Phase Epitaxy of InGaN with Large Indium Mole Fraction

    NASA Astrophysics Data System (ADS)

    Kangawa, Yoshihiro; Kawaguchi, Norihito; Hida, Ken-nosuke; Kumagai, Yoshinao; Koukitu, Akinori

    2004-08-01

    The indium composition of the InGaN film increases with decreasing growth temperature; however, the crystalline quality of the film is poor when it is grown at low temperatures. To form a high-quality InGaN film with a large indium mole fraction, Nd: YAG pulse laser assisted metalorganic vapor phase epitaxy (MOVPE) was carried out at low temperatures. The results suggest that film quality can be improved by pulse laser irradiation on the surface of the film.

  20. Comparison of the regional CO2 mole fraction filtering approaches at a WMO/GAW regional station in China

    NASA Astrophysics Data System (ADS)

    Fang, S. X.; Tans, P. P.; Steinbacher, M.; Zhou, L. X.; Luan, T.

    2015-12-01

    The identification of atmospheric CO2 observation data which are minimally influenced by very local emissions/removals is essential for trend analysis, for the estimation of regional sources and sinks, and for the modeling of long-range transport of CO2. In this study, four approaches are used to filter the atmospheric CO2 observation records from 2009 to 2011 at one World Meteorological Organization/Global Atmosphere Watch (WMO/GAW) regional station (Lin'an, LAN) in China. The methods are based on the concentration of atmospheric black carbon (BC), on a statistical approach (robust extraction of baseline signal, REBS), on CH4 as an auxiliary tracer (AUX), and on meteorological parameters (MET). All approaches do suitably well to capture the seasonal CO2 cycle at LAN. Differences are observed in the average regional mole fractions with annual values in the REBS method at least 1.7 ± 0.2 ppm higher than the other methods. The BC method may underestimate the regional CO2 mole fractions during the winter-spring period and should be treated with caution. The REBS method is a purely statistical method and it may also introduce errors on the regional CO2 mole fraction evaluations, as the filtered trend may be influenced by the "noisy" raw data series. Although there are correlations between CH4 and CO2 mole fractions at LAN, the different source/sink regimes may introduce bias on the regional CO2 estimation in the AUX method, typically in summer. Overall, the MET method seems to be the most favorable because it mainly focuses on the influence of potential local sources and sinks, and considers diurnal variations and meteorological conditions. Using the MET method, the annual growth rate of regional CO2 at LAN is determined to be 3.1 ± 0.01 ppm yr-1 (standard error) from 2009 to 2011.

  1. Study of the regional CO2 mole fractions filtering approach at a WMO/GAW regional station in China

    NASA Astrophysics Data System (ADS)

    Fang, S. X.; Tans, P. P.; Steinbacher, M.; Zhou, L. X.; Luan, T.

    2015-07-01

    The identification of atmospheric CO2 observation data which is minimally influenced by very local emissions/removals is essential for the estimation of trend analysis, regional sources and sinks, and for modeling of long-range transport of CO2. In this study, four approaches are used to filter the atmospheric CO2 observation records from 2009 to 2011 at one World Meteorological Organization/Global Atmosphere Watch (WMO/GAW) regional station (Lin'an, LAN) in China. The methods are based on the atmospheric black carbon concentration (BC), on a statistical approach (REBS), on CH4 as auxiliary tracer (AUX) and on meteorological parameters (MET). All approaches do suitably well to capture the seasonal CO2 cycle at LAN. Differences are observed in the average regional mole fractions with annual values in the REBS method at least 1.7 ± 0.2 ppm higher than the other methods. The BC method may underestimate the regional CO2 mole fractions during winter-spring period and should be treated with caution. The REBS method is a purely statistical method and it may also introduce errors on the regional CO2 mole fractions evaluations, as the filtered trend may be deviated by the "noisy" raw data series. Although there are correlations between CH4 and CO2 mole fractions at LAN, the different source/sink regimes may introduce bias on the regional CO2 estimation in the AUX method, typically in summer. Overall, the MET method seems to be the most favorable because it mainly focuses on the influence of potential local sources and sinks and considers diurnal variations, local topography, and meteorological conditions. Using the MET method, the annual growth rate of regional CO2 at LAN is determined to be 3.1 ± 0.01 ppm yr-1 (standard error) from 2009 to 2013.

  2. Multiple primary cutaneous melanomas in patients with FAMMM syndrome and sporadic atypical mole syndrome (AMS): what's worse?

    PubMed

    Tchernev, Georgi; Ananiev, Julian; Cardoso, José-Carlos; Chokoeva, Anastasiya Atanasova; Philipov, Stanislav; Penev, Plamen Kolev; Lotti, Torello; Wollina, Uwe

    2014-08-01

    Atypical Mole Syndrome is the most important phenotypic risk factor for cutaneous melanoma, a malignancy that accounts for about 80% of deaths from skin cancer. Since early diagnosis of melanoma is of great prognostic relevance, the identification of Atypical Mole Syndrome carriers (sporadic and familial) is essential, as well as the recommendation of preventative measures that must be undertaken by these patients.We report two rare cases concerning patients with multiple primary skin melanomas in the setting of a familial and a sporadic syndrome of dysplastic nevi: the first patient is a 67-year-old patient with a history of multiple superficial spreading melanomas localized on his back. The second patient presented with multiple primary melanomas in advanced stage in the context of the so-called sporadic form of the syndrome of dysplastic nevi-AMS (atypical mole syndrome). In the first case, excision of the melanomas was carried out with an uneventful post-operative period. In the second case, disseminated metastases were detected, involving the right fibula, the abdominal cavity as well as multiple lesions in the brain. The patient declined BRAF mutation tests as well as chemotherapy or targeted therapies, and suffered a rapid deterioration in his general condition leading to death. We classified the second case as a sporadic form of the atypical mole syndrome, associated with one nodular and two superficial spreading melanomas.There are no data in the literature to allow us to understand if, in patients with multiple primary melanomas, there is any difference in terms of prognosis between those with and without a family history of a similar phenotype. To answer this and other questions related to these rare cases, further studies with a significant number of patients should be carried out.

  3. Organization of the main olfactory bulbs of some mammals: musk shrews, moles, hedgehogs, tree shrews, bats, mice, and rats.

    PubMed

    Kosaka, Katsuko; Kosaka, Toshio

    2004-04-19

    We immunohistochemically examined the organization of the main olfactory bulbs (MOBs) in seven mammalian species, including moles, hedgehogs, tree shrews, bats, and mice as well as laboratory musk shrews and rats. We focused our investigation on two points: 1) whether nidi, particular spheroidal synaptic regions subjacent to glomeruli, which we previously reported for the laboratory musk shrew MOBs, are also present in other animals and 2) whether the compartmental organization of glomeruli and two types of periglomerular cells we proposed for the rat MOBs are general in other animals. The general laminar pattern was similar among these seven species, but discrete nidi and the nidal layer were recognized only in two insectivores, namely, the mole and laboratory musk shrew. Olfactory marker protein-immunoreactive (OMP-IR) axons extended beyond the limits of the glomerular layer (GL) into the superficial region of the external plexiform layer (EPL) or the nidal layer in the laboratory musk shrew, mole, hedgehog, and tree shrew but not in bat, mouse, and rat. We observed, in nidi and the nidal layer in the mole and laboratory musk shrew MOBs, only a few OMP-IR axons. In the hedgehog, another insectivore, OMP-IR processes extending from the glomeruli were scattered and intermingled with calbindin D28k-IR cells at the border between the GL and the EPL. In the superficial region of the EPL of the tree shrew MOBs, there were a small number of tiny glomerulus-like spheroidal structures where OMP-IR axons protruding from glomeruli were intermingled with dendritic branches of surrounding calbindin D28k-IR cells. Furthermore, we recognized the compartmental organization of glomeruli and two types of periglomerular cells in the MOBs of all of the mammals we examined. These structural features are therefore considered to be common and important organizational principles of the MOBs.

  4. Challenging the inbreeding hypothesis in a eusocial mammal: population genetics of the naked mole-rat, Heterocephalus glaber.

    PubMed

    Ingram, Colleen M; Troendle, Nicholas J; Gill, Clare A; Braude, Stanton; Honeycutt, Rodney L

    2015-10-01

    The role of genetic relatedness in the evolution of eusociality has been the topic of much debate, especially when contrasting eusocial insects with vertebrates displaying reproductive altruism. The naked mole-rat, Heterocephalus glaber, was the first described eusocial mammal. Although this discovery was based on an ecological constraints model of eusocial evolution, early genetic studies reported high levels of relatedness in naked mole-rats, providing a compelling argument that low dispersal rates and consanguineous mating (inbreeding as a mating system) are the driving forces for the evolution of this eusocial species. One caveat to accepting this long-held view is that the original genetic studies were based on limited sampling from the species' geographic distribution. A growing body of evidence supports a contrary view, with the original samples not representative of the species-rather reflecting a single founder event, establishing a small population south of the Athi River. Our study is the first to address these competing hypotheses by examining patterns of molecular variation in colonies sampled from north and south of the Athi and Tana rivers, which based on our results, serve to isolate genetically distinct populations of naked mole-rats. Although colonies south of the Athi River share a single mtDNA haplotype and are fixed at most microsatellite loci, populations north of the Athi River are considerably more variable. Our findings support the position that the low variation observed in naked mole-rat populations south of the Athi River reflects a founder event, rather than a consequence of this species' unusual mating system.

  5. Naked mole-rats maintain healthy skeletal muscle and Complex IV mitochondrial enzyme function into old age

    PubMed Central

    Stoll, Elizabeth A; Karapavlovic, Nevena; Rosa, Hannah; Woodmass, Michael; Rygiel, Karolina; White, Kathryn; Turnbull, Douglass M; Faulkes, Chris G

    2016-01-01

    The naked mole-rat (NMR) Heterocephalus glaber is an exceptionally long-lived rodent, living up to 32 years in captivity. This extended lifespan is accompanied by a phenotype of negligible senescence, a phenomenon of very slow changes in the expected physiological characteristics with age. One of the many consequences of normal aging in mammals is the devastating and progressive loss of skeletal muscle, termed sarcopenia, caused in part by respiratory enzyme dysfunction within the mitochondria of skeletal muscle fibers. Here we report that NMRs avoid sarcopenia for decades. Muscle fiber integrity and mitochondrial ultrastructure are largely maintained in aged animals. While mitochondrial Complex IV expression and activity remains stable, Complex I expression is significantly decreased. We show that aged naked mole-rat skeletal muscle tissue contains some mitochondrial DNA rearrangements, although the common mitochondrial DNA deletions associated with aging in human and other rodent skeletal muscles are not present. Interestingly, NMR skeletal muscle fibers demonstrate a significant increase in mitochondrial DNA copy number. These results have intriguing implications for the role of mitochondria in aging, suggesting Complex IV, but not Complex I, function is maintained in the long-lived naked mole rat, where sarcopenia is avoided and healthy muscle function is maintained for decades. PMID:27997359

  6. The neuronal structure of the preoptic area in the mole and the rabbit: Golgi and Nissl studies.

    PubMed

    Bogus-Nowakowska, K; Robak, A; Szteyn, S; Równiak, M; Najdzion, J; Wasilewska, B

    2006-11-01

    The present studies were carried out on the brains of the adult mole and rabbit. The preparations were made by means of the Golgi technique and the Nissl method. Two types of neurons were distinguished in the preoptic area (POA) of both species: bipolar and multipolar. The bipolar neurons have oval, fusiform or round perikarya and two dendritic trunks arising from the opposite poles of the cell body. The dendrites bifurcate once or twice. The dendritic branches have swellings, single spine-like and filiform processes. The multipolar neurons usually have triangular and quadrangular perikarya and from 3 to 5 dendritic trunks. The dendrites of the mole neurons branch sparsely, whereas the dendrites of the rabbit neurons display 2 or 3 divisions. On the dendritic branches varicosities and different protuberances were observed. The general morphology of the bipolar and multipolar neurons is similar in the mammals studied, although the neurons of the rabbit POA display a more complicated structure. Their dendritic branches show more divisions and possess more swellings and different processes than the dendrites of the neurons of the mole POA. Furthermore, of the multipolar neurons only the dendrites in POA of the rabbit were observed to have a rosary-like beaded appearance.

  7. Isolation and partial characterization of a highly divergent lineage of hantavirus from the European mole (Talpa europaea).

    PubMed

    Gu, Se Hun; Kumar, Mukesh; Sikorska, Beata; Hejduk, Janusz; Markowski, Janusz; Markowski, Marcin; Liberski, Paweł P; Yanagihara, Richard

    2016-02-19

    Genetically distinct hantaviruses have been identified in five species of fossorial moles (order Eulipotyphla, family Talpidae) from Eurasia and North America. Here, we report the isolation and partial characterization of a highly divergent hantavirus, named Nova virus (NVAV), from lung tissue of a European mole (Talpa europaea), captured in central Poland in August 2013. Typical hantavirus-like particles, measuring 80-120 nm in diameter, were found in NVAV-infected Vero E6 cells by transmission electron microscopy. Whole-genome sequences of the isolate, designated NVAV strain Te34, were identical to that amplified from the original lung tissue, and phylogenetic analysis of the full-length L, M and S segments, using maximum-likelihood and Bayesian methods, showed that NVAV was most closely related to hantaviruses harbored by insectivorous bats, consistent with an ancient evolutionary origin. Infant Swiss Webster mice, inoculated with NVAV by the intraperitoneal route, developed weight loss and hyperactivity, beginning at 16 days, followed by hind-limb paralysis and death. High NVAV RNA copies were detected in lung, liver, kidney, spleen and brain by quantitative real-time RT-PCR. Neuropathological examination showed astrocytic and microglial activation and neuronal loss. The first mole-borne hantavirus isolate will facilitate long-overdue studies on its infectivity and pathogenic potential in humans.

  8. A new definition for the mole based on the Avogadro constant: a journey from physics to chemistry.

    PubMed

    Milton, Martin J T

    2011-10-28

    The mole is the most recent addition to the set of base units that form the International System of Units, although its pre-cursor the 'gram-molecule', had been in use by both physicists and chemists for more than 120 years. A proposal has been published recently to establish a new definition for the mole based on a fixed value for the Avogadro constant. This would introduce consistent relative uncertainties for the molar and the atomic masses while making no change to the system of relative atomic masses ('atomic weights'). Although the proposal would have little impact on the measurement uncertainty of practical work, it has stimulated considerable debate about the mole and the nature of the quantity amount of substance. In this paper, the rationale for the new definition is explained against the background of changes in the way the quantity amount of substance has been used, from its first use during the early development of thermodynamics through to the use of the 'number of gram-molecules' at the end of the nineteenth century.

  9. Naked mole-rats maintain healthy skeletal muscle and Complex IV mitochondrial enzyme function into old age.

    PubMed

    Stoll, Elizabeth A; Karapavlovic, Nevena; Rosa, Hannah; Woodmass, Michael; Rygiel, Karolina; White, Kathryn; Turnbull, Douglass M; Faulkes, Chris G

    2016-12-19

    The naked mole-rat (NMR) Heterocephalus glaber is an exceptionally long-lived rodent, living up to 32 years in captivity. This extended lifespan is accompanied by a phenotype of negligible senescence, a phenomenon of very slow changes in the expected physiological characteristics with age. One of the many consequences of normal aging in mammals is the devastating and progressive loss of skeletal muscle, termed sarcopenia, caused in part by respiratory enzyme dysfunction within the mitochondria of skeletal muscle fibers. Here we report that NMRs avoid sarcopenia for decades. Muscle fiber integrity and mitochondrial ultrastructure are largely maintained in aged animals. While mitochondrial Complex IV expression and activity remains stable, Complex I expression is significantly decreased. We show that aged naked mole-rat skeletal muscle tissue contains some mitochondrial DNA rearrangements, although the common mitochondrial DNA deletions associated with aging in human and other rodent skeletal muscles are not present. Interestingly, NMR skeletal muscle fibers demonstrate a significant increase in mitochondrial DNA copy number. These results have intriguing implications for the role of mitochondria in aging, suggesting Complex IV, but not Complex I, function is maintained in the long-lived naked mole rat, where sarcopenia is avoided and healthy muscle function is maintained for decades.

  10. Isolation and partial characterization of a highly divergent lineage of hantavirus from the European mole (Talpa europaea)

    PubMed Central

    Gu, Se Hun; Kumar, Mukesh; Sikorska, Beata; Hejduk, Janusz; Markowski, Janusz; Markowski, Marcin; Liberski, Paweł P.; Yanagihara, Richard

    2016-01-01

    Genetically distinct hantaviruses have been identified in five species of fossorial moles (order Eulipotyphla, family Talpidae) from Eurasia and North America. Here, we report the isolation and partial characterization of a highly divergent hantavirus, named Nova virus (NVAV), from lung tissue of a European mole (Talpa europaea), captured in central Poland in August 2013. Typical hantavirus-like particles, measuring 80–120 nm in diameter, were found in NVAV-infected Vero E6 cells by transmission electron microscopy. Whole-genome sequences of the isolate, designated NVAV strain Te34, were identical to that amplified from the original lung tissue, and phylogenetic analysis of the full-length L, M and S segments, using maximum-likelihood and Bayesian methods, showed that NVAV was most closely related to hantaviruses harbored by insectivorous bats, consistent with an ancient evolutionary origin. Infant Swiss Webster mice, inoculated with NVAV by the intraperitoneal route, developed weight loss and hyperactivity, beginning at 16 days, followed by hind-limb paralysis and death. High NVAV RNA copies were detected in lung, liver, kidney, spleen and brain by quantitative real-time RT-PCR. Neuropathological examination showed astrocytic and microglial activation and neuronal loss. The first mole-borne hantavirus isolate will facilitate long-overdue studies on its infectivity and pathogenic potential in humans. PMID:26892544

  11. Neuroanatomical evidence for segregation of nerve fibers conveying light touch and pain sensation in Eimer's organ of the mole.

    PubMed

    Marasco, Paul D; Tsuruda, Pamela R; Bautista, Diana M; Julius, David; Catania, Kenneth C

    2006-06-13

    Talpid moles are small insectivores that live in dark underground tunnels. They depend heavily on touch to navigate and find food. Most species have an array of complex epidermal sensory structures called Eimer's organs that cover the tip of the nose. In this study, the anatomy of Eimer's organ was examined in the coast mole and star-nosed mole by using the fluorescent styryl pyridinium dye AM1-43 and immunocytochemical staining for neurofilament 200 and substance P. In addition, DiI was used to label neural components of Eimer's organ. AM1-43 labeled all of the Eimer's organ receptors after systemic injection, suggesting a role in mechanotransduction. Immunostaining with neurofilament 200 and substance P labeled distinct subtypes of sensory fibers. Substance P labeled a group of free nerve endings along the outer edge of Eimer's organ, indicating a nociceptive role for these fibers. In contrast, neurofilament 200 labeled a more central set of nerve endings, suggesting that these fibers function as low-threshold mechanoreceptors. By labeling subsets of trigeminal afferents distant from the receptor array with DiI, we revealed innervation patterns indicating that one afferent supplies the outer, substance P-positive set of free nerve endings, whereas several afferents differentially innervate the central free nerve endings. Our results suggest that the free nerve endings innervating Eimer's organ are largely mechanosensitive and may play an important role in the rapid sensory discrimination observed in these species.

  12. Ectoparasite burdens of the common mole-rat (Cryptomys hottentotus hottentotus) from the Cape Provinces of South Africa.

    PubMed

    Archer, Elizabeth K; Bennett, Nigel C; Ueckermann, Edward A; Lutermann, Heike

    2014-02-01

    The members of the African mole-rat family Bathyergidae are widely distributed across sub-Saharan Africa. Despite their well-studied biology and reproductive physiology, the current knowledge of their ectoparasite fauna is limited and ambiguous due to recent revisions of the bathyergid taxonomy. The common mole-rat (Cryptomys hottentotus hottentotus) is 1 of the most widely distributed species of these subterranean rodents. Ectoparasites were collected from 268 common mole-rats at 2 localities (Western and Northern Cape provinces) in South Africa over the course of 18 mo with the aim to document species richness, prevalence, and abundance of these ectoparasites. The aggregation of parasite species, sex bias within a species, and seasonal variation in ectoparasite burdens were investigated. A total of 4,830 individual parasites from 4 mite species (Androlaelaps scapularis, Androlaelaps capensis, Radfordia ensifera, and 1 undetermined chigger [family Trombiculidae]), 1 flea species (Cryptopsylla ingrami), and 1 louse species (Eulinognathus hilli) were collected. With the exception of R. ensifera and the chigger, all of these ectoparasites appear to be host specific either for the host species or the Bathyergidae. Aggregation indices indicated that with the exception of E. hilli, the distribution of all parasite species was highly aggregated among hosts and sex biased. Seasonal variation in prevalence, abundance, and species richness was apparent, with greater burdens in the rainy winter season. This is likely related to seasonal variation in abiotic factors but may also be affected by the timing of host reproduction and dispersal behavior.

  13. FOREWORD: International Workshop on the Avogadro Constant and the Representation of the Silicon Mole

    NASA Astrophysics Data System (ADS)

    Basile, Giuseppe; Garfagnini, Raffaello; Mana, Giovanni; Peuto, Anna; Zosi, Gianfranco

    1994-01-01

    This special issue of Metrologia brings together contributions to the International Workshop on the Avogadro Constant and the Representation of the Silicon Mole, held in Turin, Italy, from 9 to 10 March 1994. It was organized by the Istituto di Metrologia "G Colonnetti" (IMGC) del Consiglio Nazionale delle Ricerche (CNR) and the Istituto di Fisica Generale "A Avogadro" (IFG) dell'Università di Tonno. It was sponsored by the CNR, the University of Turin, the Regione Piemonte, and the Commission of the European Communities DG XII. The workshop was a follow-up to previous international meetings held in Turin to commemorate Amedeo Avogadro, one in 1911 (the centenary of the publication of his hypothesis) and another in 1957 (the centenary of his death). On this occasion the workshop was motivated by the requirements of researchers engaged in the international project on the determination of the Avogadro constant by the x-ray crystal density method. Sixty-four participants representing eight countries attended the workshop. Doctoral students in metrology from Turin University and researchers working in adjacent fields were also present. The lectures were chosen so as to review the different aspects of this project, to illustrate progress in research, and to indicate future developments to scientists working in different fields of physics, metrology and technology. Complementary approaches to the NA determination based on electrical measurements were also reported and analysed. During the workshop, a number of specialist meetings allowed experts to discuss specific topics, to exchange information on results and techniques, and to improve the coordination of their activities. In their opening addresses, Prof. C Castagnoli (Director of the IFG) and Prof. L Crovini (Director of the IMGC) welcomed the participants and introduced the work in progress with a view to making a more precise determination of the Avogadro constant. They mentioned the expected influence of this

  14. Membrane phospholipid composition may contribute to exceptional longevity of the naked mole-rat (Heterocephalus glaber): a comparative study using shotgun lipidomics.

    PubMed

    Mitchell, Todd W; Buffenstein, Rochelle; Hulbert, A J

    2007-11-01

    Phospholipids containing highly polyunsaturated fatty acids are particularly prone to peroxidation and membrane composition may therefore influence longevity. Phospholipid molecules, in particular those containing docosahexaenoic acid (DHA), from the skeletal muscle, heart, liver and liver mitochondria were identified and quantified using mass-spectrometry shotgun lipidomics in two similar-sized rodents that show an approximately 9-fold difference in maximum lifespan. The naked mole rat is the longest-living rodent known with a maximum lifespan of >28 years. Total phospholipid distribution is similar in tissues of both species; DHA is only found in phosphatidylcholines (PC), phosphatidylethanolamines (PE) and phosphatidylserines (PS), and DHA is relatively more concentrated in PE than PC. Naked mole-rats have fewer molecular species of both PC and PE than do mice. DHA-containing phospholipids represent 27-57% of all phospholipids in mice but only 2-6% in naked mole-rats. Furthermore, while mice have small amounts of di-polyunsaturated PC and PE, these are lacking in naked mole-rats. Vinyl ether-linked phospholipids (plasmalogens) are higher in naked mole-rat tissues than in mice. The lower level of DHA-containing phospholipids suggests a lower susceptibility to peroxidative damage in membranes of naked mole-rats compared to mice. Whereas the high level of plasmalogens might enhance membrane antioxidant protection in naked mole-rats compared to mice. Both characteristics possibly contribute to the exceptional longevity of naked mole-rats and may indicate a special role for peroxisomes in this extended longevity.

  15. Naked mole-rat has increased translational fidelity compared with the mouse, as well as a unique 28S ribosomal RNA cleavage.

    PubMed

    Azpurua, Jorge; Ke, Zhonghe; Chen, Iris X; Zhang, Quanwei; Ermolenko, Dmitri N; Zhang, Zhengdong D; Gorbunova, Vera; Seluanov, Andrei

    2013-10-22

    The naked mole-rat (Heterocephalus glaber) is a subterranean eusocial rodent with a markedly long lifespan and resistance to tumorigenesis. Multiple data implicate modulation of protein translation in longevity. Here we report that 28S ribosomal RNA (rRNA) of the naked mole-rat is processed into two smaller fragments of unequal size. The two breakpoints are located in the 28S rRNA divergent region 6 and excise a fragment of 263 nt. The excised fragment is unique to the naked mole-rat rRNA and does not show homology to other genomic regions. Because this hidden break site could alter ribosome structure, we investigated whether translation rate and amino acid incorporation fidelity were altered. We report that naked mole-rat fibroblasts have significantly increased translational fidelity despite having comparable translation rates with mouse fibroblasts. Although we cannot directly test whether the unique 28S rRNA structure contributes to the increased fidelity of translation, we speculate that it may change the folding or dynamics of the large ribosomal subunit, altering the rate of GTP hydrolysis and/or interaction of the large subunit with tRNA during accommodation, thus affecting the fidelity of protein synthesis. In summary, our results show that naked mole-rat cells produce fewer aberrant proteins, supporting the hypothesis that the more stable proteome of the naked mole-rat contributes to its longevity.

  16. The comparative anatomy of the abdominal gastrointestinal tract of six species of African mole-rats (Rodentia, Bathyergidae).

    PubMed

    Kotzé, Sanet H; Van Der Merwe, Elizabeth L; Bennett, Nigel C; O'Riain, M Justin

    2010-01-01

    The gastrointestinal tracts (GITs) of six species of African mole-rats (Bathyergidae) were compared. The aim was to provide a comprehensive anatomical comparison between the different species. The relative shape, length, and surface areas were taken into account to determine whether the GITs are phylogenetically constrained or exhibit anatomical adaptations in response to diets. In all six species the stomach was simple and glandular. With the exception of Heterocephalus glaber, the caecum was coiled in a flat spiral, the ascending colon was arranged in a loop of varying lengths, and a mucosal colonic papillary-lined groove was present in the ascending colon in all species. By contrast, the caecum in H. glaber was uncoiled, the ascending colon was not looped, and the groove was not papillated. A caeco-appendix was observed only in Bathyergus suillus and Georychus capensis. Hierarchical multivariate cluster analysis on the presence/absence of nine anatomical structures associated with the GIT of mole-rats revealed that H. glaber was anatomically the least similar of the six species (77.6% similarity) with respect to the nine GIT variables included. All Cryptomys species were the same (100% similarity), and two species B. suillus and G. capensis grouped together and were more similar to the Cryptomys genus (95% similarity) than they were to H. glaber. These findings support previous phylogenetic classifications. The voluminous caeco-colon in B. suillus may be explained by its ingestion of grasses in addition to below-ground storage organs of plants. We conclude that phylogeny and diet affect the GIT anatomy of the African mole rats studied here.

  17. Extended Pile Driving Model to Predict the Penetration of the Insight/HP3 Mole into the Martian Soil

    NASA Astrophysics Data System (ADS)

    Poganski, Joshua; Kömle, Norbert I.; Kargl, Günter; Schweiger, Helmut F.; Grott, Matthias; Spohn, Tilman; Krömer, Olaf; Krause, Christian; Wippermann, Torben; Tsakyridis, Georgios; Fittock, Mark; Lichtenheldt, Roy; Vrettos, Christos; Anrade, Jose E.

    2016-11-01

    The NASA InSight mission will provide an opportunity for soil investigations using the penetration data of the heat flow probe built by the German Aerospace Center DLR. The Heat flow and Physical Properties Probe (HP3) will penetrate 3 to 5 meter into the Martian subsurface to investigate the planetary heat flow. The measurement of the penetration rate during the insertion of the HP3 will be used to determine the physical properties of the soil at the landing site. For this purpose, numerical simulations of the penetration process were performed to get a better understanding of the soil properties influencing the penetration performance of HP3. A pile driving model has been developed considering all masses of the hammering mechanism of HP3. By cumulative application of individual stroke cycles it is now able to describe the penetration of the Mole into the Martian soil as a function of time, assuming that the soil parameters of the material through which it penetrates are known. We are using calibrated materials similar to those expected to be encountered by the InSight/HP3 Mole when it will be operated on the surface of Mars after the landing of the InSight spacecraft. We consider various possible scenarios, among them a more or less homogeneous material down to a depth of 3-5 m as well as a layered ground, consisting of layers with different soil parameters. Finally we describe some experimental tests performed with the latest prototype of the InSight Mole at DLR Bremen and compare the measured penetration performance in sand with our modeling results. Furthermore, results from a 3D DEM simulation are presented to get a better understanding of the soil response.

  18. SOCIAL STATUS AND SEX INDEPENDENTLY INFLUENCE ANDROGEN RECEPTOR EXPRESSION IN THE EUSOCIAL NAKED MOLE-RAT BRAIN

    PubMed Central

    Holmes, Melissa M.; Goldman, Bruce D.; Forger, Nancy G.

    2009-01-01

    Naked mole-rats (Heterocephalus glaber) are eusocial rodents that live in large subterranean colonies including a single breeding female and 1-3 breeding males; all other members of the colony, known as subordinates, are reproductively suppressed. We recently found that naked mole-rats lack many of the sex differences in the brain and spinal cord commonly found in other rodents. Instead, neural morphology is influenced by breeding status, such that breeders, regardless of sex, have more neurons than subordinates in the ventromedial nucleus of the hypothalamus (VMH), and larger overall volumes of the bed nucleus of the stria terminalis (BST), paraventricular nucleus (PVN) and medial amygdala (MeA). To begin to understand how breeding status influences brain morphology, we examined the distribution of androgen receptor (AR) immunoreactivity in gonadally intact breeders and subordinates of both sexes. All animals had AR+ nuclei in many of the same regions positive for AR in other mammals, including the VMH, BST, PVN, MeA, and the ventral portion of the premammillary nucleus (PMv). We also observed diffuse labeling throughout the pre-optic area demonstrating that distribution of the AR protein in presumptive reproductive brain nuclei is well-conserved, even in a species that exhibits remarkably little sexual dimorphism. In contrast to other rodents, however, naked mole-rats lacked AR+ nuclei in the suprachiasmatic nucleus and hippocampus. Males had more AR+ nuclei in the MeA, VMH, and PMv than did females. Surprisingly, breeders had significantly fewer AR+ nuclei than subordinates in all brain regions examined (VMH, BST, PVN, MeA, and PMv). Thus, social status is strongly correlated with AR immunoreactivity in this eusocial species. PMID:18455726

  19. Unusual Ratio between Free Thyroxine and Free Triiodothyronine in a Long-Lived Mole-Rat Species with Bimodal Ageing

    PubMed Central

    Henning, Yoshiyuki; Vole, Christiane; Begall, Sabine; Bens, Martin; Broecker-Preuss, Martina; Sahm, Arne; Szafranski, Karol; Burda, Hynek; Dammann, Philip

    2014-01-01

    Ansell's mole-rats (Fukomys anselli) are subterranean, long-lived rodents, which live in eusocial families, where the maximum lifespan of breeders is twice as long as that of non-breeders. Their metabolic rate is significantly lower than expected based on allometry, and their retinae show a high density of S-cone opsins. Both features may indicate naturally low thyroid hormone levels. In the present study, we sequenced several major components of the thyroid hormone pathways and analyzed free and total thyroxine and triiodothyronine in serum samples of breeding and non-breeding F. anselli to examine whether a) their thyroid hormone system shows any peculiarities on the genetic level, b) these animals have lower hormone levels compared to euthyroid rodents (rats and guinea pigs), and c) reproductive status, lifespan and free hormone levels are correlated. Genetic analyses confirmed that Ansell's mole-rats have a conserved thyroid hormone system as known from other mammalian species. Interspecific comparisons revealed that free thyroxine levels of F. anselli were about ten times lower than of guinea pigs and rats, whereas the free triiodothyronine levels, the main biologically active form, did not differ significantly amongst species. The resulting fT4:fT3 ratio is unusual for a mammal and potentially represents a case of natural hypothyroxinemia. Comparisons with total thyroxine levels suggest that mole-rats seem to possess two distinct mechanisms that work hand in hand to downregulate fT4 levels reliably. We could not find any correlation between free hormone levels and reproductive status, gender or weight. Free thyroxine may slightly increase with age, based on sub-significant evidence. Hence, thyroid hormones do not seem to explain the different ageing rates of breeders and non-breeders. Further research is required to investigate the regulatory mechanisms responsible for the unusual proportion of free thyroxine and free triiodothyronine. PMID:25409169

  20. Circadian rhythms of locomotor activity in solitary and social species of African mole-rats (family: Bathyergidae).

    PubMed

    Oosthuizen, Maria K; Cooper, Howard M; Bennett, Nigel C

    2003-12-01

    Mole-rats are strictly subterranean and hardly, if ever, come into contact with external light. As a result, their classical visual system is severely regressed and the circadian system proportionally expanded. The family Bathyergidae presents a unique opportunity to study the circadian system in the absence of the classical visual system in a range of species. Daily patterns of activity were studied in the laboratory under constant temperature but variable lighting regimes in individually housed animals from 3 species of mole-rat exhibiting markedly different degrees of sociality. All 3 species possessed individuals that exhibited endogenous circadian rhythms under constant darkness that entrained to a light-dark cycle. In the solitary species, Georychus capensis, 9 animals exhibited greater activity during the dark phase of the light cycle, while 2 individuals expressed more activity in the light phase of the light cycle. In the social, Cryptomys hottentotus pretoriae, 5 animals displayed the majority of their activity during the dark phase of the light cycle and the remaining 2 exhibited more activity during the light phase of the light cycle. Finally in the eusocial Cryptomys damarensis, 6 animals displayed more activity during the light phase of the light cycle, and the other 2 animals displayed more activity during the dark phase of the light cycle. Since all three mole-rat species are able to entrain their locomotor activity to an external light source, light must reach the SCN, suggesting a functional circadian clock. In comparison to the solitary species, the 2 social species display a markedly poorer response to light in all aspects. Thus, in parallel with the sociality continuum, there exists a continuum of sensitivity of the circadian clock to light.

  1. Development of traceable precision dynamic dilution method to generate dimethyl sulphide gas mixtures at sub-nanomole per mole levels for ambient measurement.

    PubMed

    Kim, Mi Eon; Kim, Yong Doo; Kang, Ji Hwan; Heo, Gwi Suk; Lee, Dong Soo; Lee, Sangil

    2016-04-01

    Dimethyl sulphide (DMS) is an important compound in global atmospheric chemistry and climate change. Traceable international standards are essential for measuring accurately the long-term global trend in ambient DMS. However, developing accurate gas standards for sub-nanomole per mole (nmol/mol) mole fractions of DMS in a cylinder is challenging, because DMS is reactive and unstable. In this study, a dynamic dilution method that is traceable and precise was developed to generate sub-nmol/mol DMS gas mixtures with a dynamic dilution system based on sonic nozzles and a long-term (>5 years) stable 10 μmol/mol parent DMS primary standard gas mixtures (PSMs). The dynamic dilution system was calibrated with traceable methane PSMs, and its estimated dilution factors were used to calculate the mole fractions of the dynamically generated DMS gas mixtures. A dynamically generated DMS gas mixture and a 6 nmol/mol DMS PSM were analysed against each other by gas chromatography with flame-ionisation detection (GC/FID) to evaluate the dilution system. The mole fractions of the dynamically generated DMS gas mixture determined against a DMS PSM and calculated with the dilution factor agreed within 1% at 6 nmol/mol. In addition, the dynamically generated DMS gas mixtures at various mole fractions between 0.4 and 11.7 nmol/mol were analysed by GC/FID and evaluated for their linearity. The analytically determined mole fractions showed good linearity with the mole fractions calculated with the dilution factors. Results showed that the dynamic dilution method generates DMS gas mixtures ranging between 0.4 nmol/mol and 12 nmol/mol with relative expanded uncertainties of less than 2%. Therefore, the newly developed dynamic dilution method is a promising reference method for generating sub-nmol/mol DMS gas standards for accurate ambient measurements.

  2. Ecology of the tawny mole cricket, Scapteriscus vicinus (Orthoptera: Gryllotalpidae): population estimation, spatial distribution, movement, and host relationships

    SciTech Connect

    Hudson, W.G.

    1985-01-01

    Scapteriscus vicinus is the most important pest of turf and pasture grasses in Florida. This study develops a method of correlating sample results with true population density and provides the first quantitative information on spatial distribution and movement patterns of mole crickets. Three basic techniques for sampling mole crickets were compared: soil flushes, soil corer, and pitfall trapping. No statistical difference was found between the soil corer and soil flushing. Soil flushing was shown to be more sensitive to changes in population density than pitfall trapping. No technique was effective for sampling adults. Regression analysis provided a means of adjusting for the effects of soil moisture and showed soil temperature to be unimportant in predicting efficiency of flush sampling. Cesium-137 was used to label females for subsequent location underground. Comparison of mean distance to nearest neighbor with the distance predicted by a random distribution model showed that the observed distance in the spring was significantly greater than hypothesized (Student's T-test, p < 0.05). Fall adult nearest neighbor distance was not different than predicted by the random distribution hypothesis.

  3. A survey of gastrointestinal parasites of olive baboons (Papio anubis) in human settlement areas of Mole National Park, Ghana.

    PubMed

    Ryan, Sadie J; Brashares, Justin S; Walsh, Chesley; Milbers, Katherine; Kilroy, Cailean; Chapman, Colin A

    2012-08-01

    Fecal samples from 55 free-ranging olive baboons (Papio anubis) in Mole National Park, Ghana, were collected 22 June-7 July 2008 and analyzed for gastrointestinal parasites. This is the first survey of baboon gastrointestinal parasites in Ghana and provides baseline data for this area. Ninety-three percent of samples were infected, leaving 7% with no parasites observed. Of those infected, there was a 76% prevalence of strongyles, 53% Strongyloides spp., 11% Abbreviata caucasica , 62% prevalence of Balantidium coli (trophozoites and cysts identified), 4% Entomeba hystolytica/dispar, and 47% unidentified protozoan parasites. Of the strongyle infections, 9% were identified as Oesophagostamum sp. One sample contained an unidentified spirurid nematode that resembled Gongylonema sp. Mole has a mixed forest-savanna habitat, and baboons frequently range into human areas, which makes them subject to parasites from each habitat and multiple sources of exposure. We found a high prevalence of nematode parasites, consistent with a wet or cooler forest environment, or high rates of fecal contamination. The presence of Strongyloides sp., E. hystolitica/dispar, and B. coli suggest potential public health risk from baboons, but molecular identification of these parasites, and documentation of their presence in local human populations, would be necessary to confirm zoonotic transmission.

  4. Walking the Oxidative Stress Tightrope: A Perspective from the Naked Mole-Rat, the Longest-Living Rodent

    PubMed Central

    Rodriguez, Karl A.; Wywial, Ewa; Perez, Viviana I.; Lambert, Adrian J.; Edrey, Yael H.; Lewis, Kaitlyn N.; Grimes, Kelly; Lindsey, Merry L.; Brand, Martin D.; Buffenstein, Rochelle

    2014-01-01

    Reactive oxygen species (ROS), by-products of aerobic metabolism, cause oxidative damage to cells and tissue and not surprisingly many theories have arisen to link ROS-induced oxidative stress to aging and health. While studies clearly link ROS to a plethora of divergent diseases, their role in aging is still debatable. Genetic knock-down manipulations of antioxidants alter the levels of accrued oxidative damage, however, the resultant effect of increased oxidative stress on lifespan are equivocal. Similarly the impact of elevating antioxidant levels through transgenic manipulations yield inconsistent effects on longevity. Furthermore, comparative data from a wide range of endotherms with disparate longevity remain inconclusive. Many long-living species such as birds, bats and mole-rats exhibit high-levels of oxidative damage, evident already at young ages. Clearly, neither the amount of ROS per se nor the sensitivity in neutralizing ROS are as important as whether or not the accrued oxidative stress leads to oxidative-damage-linked age-associated diseases. In this review we examine the literature on ROS, its relation to disease and the lessons gleaned from a comparative approach based upon species with widely divergent responses. We specifically focus on the longest lived rodent, the naked mole-rat, which maintains good health and provides novel insights into the paradox of maintaining both an extended healthspan and lifespan despite high oxidative stress from a young age. PMID:21736541

  5. Genetic structure and diversity in an isolated population of an endemic mole salamander (Ambystoma rivulare Taylor, 1940) of central Mexico.

    PubMed

    Heredia-Bobadilla, Rosa-Laura; Monroy-Vilchis, Octavio; Zarco-González, Martha M; Martínez-Gómez, Daniel; Mendoza-Martínez, Germán David; Sunny, Armando

    2016-12-01

    Human activities are affecting the distribution of species worldwide by causing fragmentation and isolation of populations. Isolation and fragmentation lead to populations with lower genetic variability and an increased chance of inbreeding and genetic drift, which results in a loss of biological fitness over time. Studies of the genetic structure of small and isolated populations are critically important for management and conservation decisions. Ambystoma rivulare is a micro-endemic Mexican mole salamander from central Mexico. It is found in the most ecologically disturbed region in Mexico, the Trans-Mexican Volcanic Belt. The goal of this study of the population genetics of the micro-endemic mole salamander was to provide information to be used as a basis for future research and conservation planning of this species and other species of the Ambystoma genus in Mexico. The structural analysis found two subpopulations, one for each river sampled, with no signs of admixture and very high levels of genetic differentiation. Medium to high levels of heterozygosity and few alleles and genotypes were observed. Evidence of an ancestral genetic bottleneck, low values of effective population size, small inbreeding coefficients, and low gene flow were also found.

  6. Walking the oxidative stress tightrope: a perspective from the naked mole-rat, the longest-living rodent.

    PubMed

    Rodriguez, Karl A; Wywial, Ewa; Perez, Viviana I; Lambert, Adriant J; Edrey, Yael H; Lewis, Kaitlyn N; Grimes, Kelly; Lindsey, Merry L; Brand, Martin D; Buffenstein, Rochelle

    2011-01-01

    Reactive oxygen species (ROS), by-products of aerobic metabolism, cause oxidative damage to cells and tissue and not surprisingly many theories have arisen to link ROS-induced oxidative stress to aging and health. While studies clearly link ROS to a plethora of divergent diseases, their role in aging is still debatable. Genetic knock-down manipulations of antioxidants alter the levels of accrued oxidative damage, however, the resultant effect of increased oxidative stress on lifespan are equivocal. Similarly the impact of elevating antioxidant levels through transgenic manipulations yield inconsistent effects on longevity. Furthermore, comparative data from a wide range of endotherms with disparate longevity remain inconclusive. Many long-living species such as birds, bats and mole-rats exhibit high-levels of oxidative damage, evident already at young ages. Clearly, neither the amount of ROS per se nor the sensitivity in neutralizing ROS are as important as whether or not the accrued oxidative stress leads to oxidative-damage-linked age-associated diseases. In this review we examine the literature on ROS, its relation to disease and the lessons gleaned from a comparative approach based upon species with widely divergent responses. We specifically focus on the longest lived rodent, the naked mole-rat, which maintains good health and provides novel insights into the paradox of maintaining both an extended healthspan and lifespan despite high oxidative stress from a young age.

  7. Multiple Loci and Complete Taxonomic Sampling Resolve the Phylogeny and Biogeographic History of Tenrecs (Mammalia: Tenrecidae) and Reveal Higher Speciation Rates in Madagascar's Humid Forests.

    PubMed

    Everson, Kathryn M; Soarimalala, Voahangy; Goodman, Steven M; Olson, Link E

    2016-09-01

    The family Tenrecidae (tenrecs) is one of only four extant terrestrial mammal lineages to have colonized and diversified on Madagascar. Over the last 15 years, several studies have disagreed on relationships among major tenrec lineages, resulting in multiple reinterpretations of the number and timing of historical transoceanic dispersal events between Africa and Madagascar. We reconstructed the phylogeny of Tenrecidae using multiple loci from all recognized extant species and estimated divergence timing using six fossil calibrations within Afrotheria. All phylogenetic analyses strongly support monophyly of the Malagasy tenrecs, and our divergence timing analysis places their colonization of the island at 30-56 Ma. Our comprehensive phylogeny supports three important taxonomic revisions that reflect the evolutionary history of tenrecs: (1) we formally elevate the African otter shrews to their own family Potamogalidae, thereby rendering extant Tenrecidae entirely endemic to Madagascar; (2) we subsume the semiaquatic genus Limnogale within the shrew tenrec genus Microgale; and (3) we re-elevate the two largest-bodied shrew tenrecs, Microgale dobsoni and Microgale talazaci, to the genus Nesogale Thomas (1918) Finally, we use recently summarized habitat data to test the hypothesis that diversification rates differ between humid and arid habitats on Madagascar, and we compare three common methods for ancestral biogeographic reconstruction. These analyses suggest higher speciation rates in humid habitats and reveal a minimum of three and more likely five independent transitions to arid habitats. Our results resolve the relationships among previously recalcitrant taxa, illuminate the timing and mechanisms of major biogeographic patterns in an extraordinary example of an island radiation, and permit the first comprehensive, phylogenetically consistent taxonomy of Madagascar's tenrecs.

  8. Giant invasive mole presenting as a cause of abdominopelvic mass in a perimenopausal woman: An unusual presentation of a rare pathology

    PubMed Central

    Şimşek, Memet; Üçer, Özlem

    2016-01-01

    Invasive mole is a benign gestational trophoblastic disease that arises from the myometrial invasion of any gestational event via direct extension through tissue or vascular structures. Invasive mole (and other gestational trophoblastic diseases) may present with life-threatening complications including uterine perforation, excessive bleeding, acute hemoperitoneum, and abdominal pain. We report a case of invasive mole presenting as abdominal distention in a 51-year-old perimenopausal woman (gravida 12, para 12, abortion 0). The patient was admitted to the gynecology clinic with a giant uterine mass filling the pelvic and abdominal cavity. To our knowledge, this is the first case in the literature of a gestational trophoblastic neoplasia presenting with uterine mass of 28 weeks' gestational size in this age group. Interestingly, complications such as uterine rupture or invasion of the adjacent structures (such as parametrial tissues or blood vessels) had not developed in our patient despite the considerable enlargement of the uterus. PMID:27896261

  9. Low sulfide levels and a high degree of cystathionine β-synthase (CBS) activation by S-adenosylmethionine (SAM) in the long-lived naked mole-rat.

    PubMed

    Dziegelewska, Maja; Holtze, Susanne; Vole, Christiane; Wachter, Ulrich; Menzel, Uwe; Morhart, Michaela; Groth, Marco; Szafranski, Karol; Sahm, Arne; Sponholz, Christoph; Dammann, Philip; Huse, Klaus; Hildebrandt, Thomas; Platzer, Matthias

    2016-08-01

    Hydrogen sulfide (H2S) is a gaseous signalling molecule involved in many physiological and pathological processes. There is increasing evidence that H2S is implicated in aging and lifespan control in the diet-induced longevity models. However, blood sulfide concentration of naturally long-lived species is not known. Here we measured blood sulfide in the long-lived naked mole-rat and five other mammalian species considerably differing in lifespan and found a negative correlation between blood sulfide and maximum longevity residual. In addition, we show that the naked mole-rat cystathionine β-synthase (CBS), an enzyme whose activity in the liver significantly contributes to systemic sulfide levels, has lower activity in the liver and is activated to a higher degree by S-adenosylmethionine compared to other species. These results add complexity to the understanding of the role of H2S in aging and call for detailed research on naked mole-rat transsulfuration.

  10. At the foot of the shrew: manus morphology distinguishes closely-related Cryptotis goodwini and Cryptotis griseoventris (Mammalia: Soricidae) in Central America

    USGS Publications Warehouse

    Woodman, Neal; Stephens, Ryan B.

    2010-01-01

    Small-eared shrews (Mammalia, Soricidae) of the New World genus Cryptotis are distributed from eastern North America to the northern Andes of South America. One well-defined clade in this genus is the Central American Cryptotis mexicana group, whose members are set off from other species in the genus by their variably broader fore feet and more elongate and broadened fore claws. Two species in the C. mexicana group, Cryptotis goodwini Jackson and Cryptotis griseoventris Jackson, inhabit highlands in Guatemala and southern Mexico and are presumed to be sister species whose primary distinguishing feature is the larger body size of C. goodwini. To better characterize these species and confirm the identification of recently-collected specimens, we obtained digital X-ray images of the manus from large series of dried skins of both species. Measurements of the metacarpals and phalanges successfully separated most specimens of C. goodwini and C. griseoventris. These measurements also show that the fore feet of C. griseoventris from Chiapas, Mexico, are morphologically distinct from those of members of the species inhabiting Guatemala. Univariate, bivariate, and multivariate analyses indicate that fore foot characters are more conservative within species of the C. mexicana group than are cranio-mandibular characters. Patterns of evolution of fore foot characters that superficially appear to be linear gradations are actually more complex, illustrating individual evolutionary trajectories.

  11. Biomic Specialization and Speciation Rates in Ruminants (Cetartiodactyla, Mammalia): A Test of the Resource-Use Hypothesis at the Global Scale

    PubMed Central

    Cantalapiedra, Juan L.; Hernández Fernández, Manuel; Morales, Jorge

    2011-01-01

    The resource-use hypothesis proposed by E.S. Vrba predicts that specialist species have higher speciation and extinction rates than generalists because they are more susceptible to environmental changes and vicariance. In this work, we test some of the predictions derived from this hypothesis on the 197 extant and recently extinct species of Ruminantia (Cetartiodactyla, Mammalia) using the biomic specialization index (BSI) of each species, which is based on its distribution within different biomes. We ran 10000 Monte Carlo simulations of our data in order to get a null distribution of BSI values against which to contrast the observed data. Additionally, we drew on a supertree of the ruminants and a phylogenetic likelihood-based method (QuaSSE) for testing whether the degree of biomic specialization affects speciation rates in ruminant lineages. Our results are consistent with the predictions of the resource-use hypothesis, which foretells a higher speciation rate of lineages restricted to a single biome (BSI = 1) and higher frequency of specialist species in biomes that underwent high degree of contraction and fragmentation during climatic cycles. Bovids and deer present differential specialization across biomes; cervids show higher specialization in biomes with a marked hydric seasonality (tropical deciduous woodlands and schlerophyllous woodlands), while bovids present higher specialization in a greater variety of biomes. This might be the result of divergent physiological constraints as well as a different biogeographic and evolutionary history. PMID:22174888

  12. Patterns of morphological variation amongst semifossorial shrews in the highlands of Guatemala, with the description of a new species (Mammalia, Soricomorpha, Soricidae)

    USGS Publications Warehouse

    Woodman, Neal

    2011-01-01

    Members of the Cryptotis goldmani group of small-eared shrews (Mammalia, Soricomorpha, Soricidae) represent a clade within the genus that is characterized by modifications of the forelimb that include broadened forefeet, elongated and broadened foreclaws, and massive humeri with enlarged processes. These modifications are consistent with greater adaptation to their semifossorial habits than other members of the genus. The species in this group occur discontinuously in temperate highlands from southern Tamaulipas, Mexico, to Honduras. In Guatemala, there are three species: the relatively widespread Cryptotis goodwini and two species (Cryptotis lacertosus, Cryptotis mam) endemic to highland forests in the Sierra de los Cuchumatanes of western Guatemala. Ongoing studies focusing on the relationships of variation in cranial and postcranial skeletal morphology have revealed a fourth species from remnant cloud forest in the Sierra de Yalijux, central Guatemala. In this paper, I describe this new species and characterize its morphology relative to other species in the C. goldmani group and to other species of Cryptotis in Guatemala. In addition, I summarize available details of its habitat and ecology.

  13. (30)Si mole fraction of a silicon material highly enriched in (28)Si determined by instrumental neutron activation analysis.

    PubMed

    D'Agostino, Giancarlo; Di Luzio, Marco; Mana, Giovanni; Oddone, Massimo; Pramann, Axel; Prata, Michele

    2015-06-02

    The latest determination of the Avogadro constant, carried out by counting the atoms in a pure silicon crystal highly enriched in (28)Si, reached the target 2 × 10(-8) relative uncertainty required for the redefinition of the kilogram based on the Planck constant. The knowledge of the isotopic composition of the enriched silicon material is central; it is measured by isotope dilution mass spectrometry. In this work, an independent estimate of the (30)Si mole fraction was obtained by applying a relative measurement protocol based on Instrumental Neutron Activation Analysis. The amount of (30)Si isotope was determined by counting the 1266.1 keV γ-photons emitted during the radioactive decay of the radioisotope (31)Si produced via the neutron capture reaction (30)Si(n,γ)(31)Si. The x((30)Si) = 1.043(19) × 10(-6) mol mol(-1) is consistent with the value currently adopted by the International Avogadro Coordination.

  14. Rotational diffusion of ionic and neutral solutes in mixed micelles: Effect of surfactant to block copolymer mole ratio on solute rotation

    NASA Astrophysics Data System (ADS)

    Mali, K. S.; Dutt, G. B.; Mukherjee, T.

    2007-10-01

    Rotational diffusion of an ionic solute rhodamine 110 and a neutral solute 2,5-dimethyl-1,4-dioxo-3,6-diphenylpyrrolo[3,4-c]pyrrole (DMDPP) has been investigated in aqueous mixtures of cetyltrimethylammonium chloride (CTAC) and poly(ethyleneoxide)20-poly(propyleneoxide)70-poly(ethyleneoxide)20 (P123). The purpose of this work is to understand how an increase in the mole ratio of surfactant to block copolymer from low to high influences the dynamics of ionic and neutral solute molecules. The variation in the mole ratio of CTAC to P123 from low to high has resulted in a drastic increase in the average reorientation time of rhodamine 110. In contrast, an exactly opposite trend has been noticed in the case of DMDPP. In the low mole ratio regime, rhodamine 110 and DMDPP are located at the interface and palisade layer, respectively, of P123 micelle-CTAC complexes. On the other hand, in the high mole ratio regime, both the probes are located in the Stern layer of CTAC-P123 complexes. The enhancement in the average reorientation time of rhodamine 110 with an increase in the mole ratio of surfactant to block copolymer has been rationalized on the basis of formation of rhodamine 110-Cl ion pair, which in turn associates with the cationic head groups of CTAC-P123 complexes. The observed decrease in the average reorientation time of DMDPP with an increase in the mole ratio of CTAC to P123 is a consequence of lower microviscosity of the Stern layer of CTAC-P123 complexes compared to the palisade layer of P123 micelle-CTAC complexes.

  15. Interglacial refugia preserved high genetic diversity of the Chinese mole shrew in the mountains of southwest China

    PubMed Central

    He, K; Hu, N-Q; Chen, X; Li, J-T; Jiang, X-L

    2016-01-01

    The mountains of southwest China (MSC) harbor extremely high species diversity; however, the mechanism behind this diversity is unknown. We investigated to what degree the topography and climate change shaped the genetic diversity and diversification in these mountains, and we also sought to identify the locations of microrefugia areas in these mountains. For these purposes, we sampled extensively to estimate the intraspecific phylogenetic pattern of the Chinese mole shrew (Anourosorex squamipes) in southwest China throughout its range of distribution. Two mitochondrial genes, namely, cytochrome b (CYT B) and NADH dehydrogenase subunit 2 (ND2), from 383 archived specimens from 43 localities were determined for phylogeographic and demographic analyses. We used the continuous-diffusion phylogeographic model, extensive Bayesian skyline plot species distribution modeling (SDM) and approximate Bayesian computation (ABC) to explore the changes in population size and distribution through time of the species. Two phylogenetic clades were identified, and significantly higher genetic diversity was preserved in the southern subregion of the mountains. The results of the SDM, continuous-diffusion phylogeographic model, extensive Bayesian skyline plot and ABC analyses were congruent and supported that the Last Interglacial Maximum (LIG) was an unfavorable period for the mole shrews because of a high degree of seasonality; A. squamipes survived in isolated interglacial refugia mainly located in the southern subregion during the LIG and rapidly expanded during the last glacial period. These results furnished the first evidence for major Pleistocene interglacial refugia and a latitudinal effect in southwest China, and the results shedding light on the higher level of species richness in the southern subregion. PMID:26286667

  16. Automatic processing of atmospheric CO2 and CH4 mole fractions at the ICOS Atmosphere Thematic Centre

    NASA Astrophysics Data System (ADS)

    Hazan, Lynn; Tarniewicz, Jérôme; Ramonet, Michel; Laurent, Olivier; Abbaris, Amara

    2016-09-01

    The Integrated Carbon Observation System Atmosphere Thematic Centre (ICOS ATC) automatically processes atmospheric greenhouse gases mole fractions of data coming from sites of the ICOS network. Daily transferred raw data files are automatically processed and archived. Data are stored in the ICOS atmospheric database, the backbone of the system, which has been developed with an emphasis on the traceability of the data processing. Many data products, updated daily, explore the data through different angles to support the quality control of the dataset performed by the principal operators in charge of the instruments. The automatic processing includes calibration and water vapor corrections as described in the paper. The mole fractions calculated in near-real time (NRT) are automatically revaluated as soon as a new instrument calibration is processed or when the station supervisors perform quality control. By analyzing data from 11 sites, we determined that the average calibration corrections are equal to 1.7 ± 0.3 µmol mol-1 for CO2 and 2.8 ± 3 nmol mol-1 for CH4. These biases are important to correct to avoid artificial gradients between stations that could lead to error in flux estimates when using atmospheric inversion techniques. We also calculated that the average drift between two successive calibrations separated by 15 days amounts to ±0.05 µmol mol-1 and ±0.7 nmol mol-1 for CO2 and CH4, respectively. Outliers are generally due to errors in the instrument configuration and can be readily detected thanks to the data products provided by the ATC. Several developments are still ongoing to improve the processing, including automated spike detection and calculation of time-varying uncertainties.

  17. Spatial and Temporal Activity Patterns of the Free-Living Giant Mole-Rat (Fukomys mechowii), the Largest Social Bathyergid

    PubMed Central

    Lövy, Matěj; Šklíba, Jan; Šumbera, Radim

    2013-01-01

    Despite the considerable attention devoted to the biology of social species of African mole-rats (Bathyergidae, Rodentia), knowledge is lacking about their behaviour under natural conditions. We studied activity of the largest social bathyergid, the giant mole-rat Fukomys mechowii, in its natural habitat in Zambia using radio-telemetry. We radio-tracked six individuals during three continuous 72-h sessions. Five of these individuals, including a breeding male, belonged to a single family group; the remaining female was probably a solitary disperser. The non-breeders of the family were active (i.e. outside the nest) 5.8 hours per 24h-day with the activity split into 6.5 short bouts. The activity was more concentrated in the night hours, when the animals also travelled longer distances from the nest. The breeding male spent only 3.2 hours per day outside the nest, utilizing less than 20% of the whole family home range. The dispersing female displayed a much different activity pattern than the family members. Her 8.0 hours of outside-nest activity per day were split into 4.6 bouts which were twice as long as in the family non-breeders. Her activity peak in the late afternoon coincided with the temperature maximum in the depth of 10 cm (roughly the depth of the foraging tunnels). Our results suggest that the breeding individuals (at least males) contribute very little to the work of the family group. Nevertheless, the amount of an individual's activity and its daily pattern are probably flexible in this species and can be modified in response to actual environmental and social conditions. PMID:23383166

  18. DNA sequence variation in the mitochondrial control region of subterranean mole rats, Spalax ehrenbergi superspecies, in Israel.

    PubMed

    Reyes, Aurelio; Nevo, Eviatar; Saccone, Cecilia

    2003-04-01

    The complete mitochondrial control region was sequenced for 60 individuals representing different populations for each of the four species of the subterranean mole rat Spalax ehrenbergi superspecies in Israel: Spalax galili (2n = 52), S. golani (2n = 54), S. carmeli (2n = 58), and S. judaei (2n = 60). The control region of all species and populations is very similar both in length (979 to 983 bp) and in base composition. As in agreement with previous surveys on mitochondrial control regions on mammals, the mole rat control region can be divided into a central domain and two flanking domains, ETAS (extended termination associated sequences) and CSB (conserved sequence blocks). Along with the common conserved blocks found in these domains (ETAS1, ETAS2, CSB1, CSB2, and CSB3), we have also detected in all individuals an ETAS1-like and a CSB1-like element, both in the ETAS domain. The most conserved region was the central domain, followed by the CSB and ETAS domains, showing important differences in the four species analyzed. Phylogenetic analysis supported the existence of two clades. One clade contained individuals belonging to Spalax galili (2n = 52) and S. golani (2n = 54), separated in two different branches depending on the species. The other clade contained individuals belonging to S. carmeli (2n = 58) and S. judaei (2n = 60) mixed together, suggesting a more recent event of speciation. Within species we have observed a southward trend of increasing variability. These results have been explained as a consequence of the adaptation of the species to ecological factors such as aridity and temperature stresses.

  19. The Mars Underground Mole (MUM): A Subsurface Penetration Device with Infrared Reflectance and Raman Spectroscopic Sensing Capability

    NASA Technical Reports Server (NTRS)

    Stoker, C. R.; Richter, L.; Smith, W. H.; Lemke, L. G.; Hammer, P.; Dalton, J. B.; Glass, B.; Zent, A.

    2003-01-01

    Searching for evidence of life on Mars will probably require access to the subsurface. The Martian surface is bathed in ultraviolet radiation which decomposes organic compounds, destroying possible evidence for life. Also, experiments performed by the Viking Landers imply the presence of several strongly oxidizing compounds at the Martian surface that may also play a role in destroying organic compounds near the surface. While liquid water is unstable on the Martian surface, and ice is unstable at the surface at low latitudes, recent results from the Mars Odyssey Gamma Ray Spectrometer experiment indicate that water ice is widely distributed near the surface under a thin cover of dry soil. Organic compounds created by an ancient Martian biosphere might be preserved in such ice-rich layers. Furthermore, accessing the subsurface provides a way to identify unique stratigraphy such as small-scale layering associated with lacustrine sediments. Subsurface access might also provide new insights into the Mars climate record that may be preserved in the Polar Layered Deposits. Recognizing the importance of accessing the subsurface of Mars to the future scientific exploration of the planet, the Mars Surveyor 2007 Science Definition Team called for drilling beneath the surface soils. Subsurface measurements are also cited as high priority in by MEPAG. Recognizing the importance of accessing the Martian subsurface to search for life, the European Space Agency has incorporated a small automated burrowing device called a subsurface penetrometer or Mole onto the Beagle 2 lander planned for 2003 launch. This device, called the Planetary Underground Tool (PLUTO), is a pointed slender cylinder 2 cm wide and 28 cm long equipped with a small sampling device at the pointed end that collects samples and brings them to the surface for analysis. Drawing on the PLUTO design, we are developing a larger Mole carrying sensors for identifying mineralogy, organic compounds, and water.

  20. Interglacial refugia preserved high genetic diversity of the Chinese mole shrew in the mountains of southwest China.

    PubMed

    He, K; Hu, N-Q; Chen, X; Li, J-T; Jiang, X-L

    2016-01-01

    The mountains of southwest China (MSC) harbor extremely high species diversity; however, the mechanism behind this diversity is unknown. We investigated to what degree the topography and climate change shaped the genetic diversity and diversification in these mountains, and we also sought to identify the locations of microrefugia areas in these mountains. For these purposes, we sampled extensively to estimate the intraspecific phylogenetic pattern of the Chinese mole shrew (Anourosorex squamipes) in southwest China throughout its range of distribution. Two mitochondrial genes, namely, cytochrome b (CYT B) and NADH dehydrogenase subunit 2 (ND2), from 383 archived specimens from 43 localities were determined for phylogeographic and demographic analyses. We used the continuous-diffusion phylogeographic model, extensive Bayesian skyline plot species distribution modeling (SDM) and approximate Bayesian computation (ABC) to explore the changes in population size and distribution through time of the species. Two phylogenetic clades were identified, and significantly higher genetic diversity was preserved in the southern subregion of the mountains. The results of the SDM, continuous-diffusion phylogeographic model, extensive Bayesian skyline plot and ABC analyses were congruent and supported that the Last Interglacial Maximum (LIG) was an unfavorable period for the mole shrews because of a high degree of seasonality; A. squamipes survived in isolated interglacial refugia mainly located in the southern subregion during the LIG and rapidly expanded during the last glacial period. These results furnished the first evidence for major Pleistocene interglacial refugia and a latitudinal effect in southwest China, and the results shedding light on the higher level of species richness in the southern subregion.

  1. Redefinition of the kilogram, ampere, kelvin and mole: a proposed approach to implementing CIPM recommendation 1 (CI-2005)

    NASA Astrophysics Data System (ADS)

    Mills, Ian M.; Mohr, Peter J.; Quinn, Terry J.; Taylor, Barry N.; Williams, Edwin R.

    2006-06-01

    The International System of Units (SI) is founded on seven base units, the metre, kilogram, second, ampere, kelvin, mole and candela corresponding to the seven base quantities of length, mass, time, electric current, thermodynamic temperature, amount of substance and luminous intensity. At its 94th meeting in October 2005, the International Committee for Weights and Measures (CIPM) adopted a recommendation on preparative steps towards redefining the kilogram, ampere, kelvin and mole so that these units are linked to exactly known values of fundamental constants. We propose here that these four base units should be given new definitions linking them to exactly defined values of the Planck constant h, elementary charge e, Boltzmann constant k and Avogadro constant NA, respectively. This would mean that six of the seven base units of the SI would be defined in terms of true invariants of nature. In addition, not only would these four fundamental constants have exactly defined values but also the uncertainties of many of the other fundamental constants of physics would be either eliminated or appreciably reduced. In this paper we present the background and discuss the merits of these proposed changes, and we also present possible wordings for the four new definitions. We also suggest a novel way to define the entire SI explicitly using such definitions without making any distinction between base units and derived units. We list a number of key points that should be addressed when the new definitions are adopted by the General Conference on Weights and Measures (CGPM), possibly by the 24th CGPM in 2011, and we discuss the implications of these changes for other aspects of metrology.

  2. Subcaste differences in neural activation suggest a prosocial role for oxytocin in eusocial naked mole-rats.

    PubMed

    Hathaway, Georgia A; Faykoo-Martinez, Mariela; Peragine, Deane E; Mooney, Skyler J; Holmes, Melissa M

    2016-03-01

    The neuropeptide oxytocin (OT) influences prosocial behavior(s), aggression, and stress responsiveness, and these diverse effects are regulated in a species- and context-specific manner. The naked mole-rat (Heterocephalus glaber) is a unique species with which to study context-dependent effects of OT, exhibiting a strict social hierarchy with behavioral specialization within the subordinate caste: soldiers are aggressive and defend colonies against unfamiliar conspecifics while workers are prosocial and contribute to in-colony behaviors such as pup care. To determine if OT is involved in subcaste-specific behaviors, we compared behavioral responses between workers and soldiers of both sexes during a modified resident/intruder paradigm, and quantified activation of OT neurons in the hypothalamic paraventricular nucleus (PVN) and supraoptic nucleus (SON) using the immediate-early-gene marker c-fos co-localized with OT neurons. Resident workers and soldiers were age-matched with unfamiliar worker stimulus animals as intruders, and encounters were videorecorded and scored for aggressive behaviors. Colony-matched controls were left in their home colony for the duration of the encounters. Brains were extracted and cell counts were conducted for OT immunoreactive (ir), c-fos-ir, and percentage of OT-c-fos double-labeled cells. Results indicate that resident workers were less aggressive but showed greater OT neural activity than soldiers. Furthermore, a linear model including social treatment, cortisol, and subcaste revealed that subcaste was the only significant predictor of OT-c-fos double-labeled cells in the PVN. These data suggest that in naked mole-rats OT promotes prosocial behaviors rather than aggression and that even within subordinates status exerts robust effects on brain and behavior.

  3. Metabolic clues to salubrious longevity in the brain of the longest-lived rodent: the naked mole-rat.

    PubMed

    Triplett, Judy C; Swomley, Aaron; Kirk, Jessime; Lewis, Katilyn; Orr, Miranda; Rodriguez, Karl; Cai, Jian; Klein, Jon B; Buffenstein, Rochelle; Butterfield, D Allan

    2015-08-01

    Naked mole-rats (NMRs) are the oldest-living rodent species. Living underground in a thermally stable ecological niche, NMRs have evolved certain exceptional traits, resulting in sustained health spans, negligible cognitive decline, and a pronounced resistance to age-related disease. Uncovering insights into mechanisms underlying these extraordinary traits involved in successful aging may conceivably provide crucial clues to extend the human life span and health span. One of the most fundamental processes inside the cell is the production of ATP, which is an essential fuel in driving all other energy-requiring cellular activities. Not surprisingly, a prominent hallmark in age-related diseases, such as neurodegeneration and cancer, is the impairment and dysregulation of metabolic pathways. Using a two-dimensional polyacrylamide gel electrophoresis proteomics approach, alterations in expression and phosphorylation levels of metabolic proteins in the brains of NMRs, aged 2-24 years, were evaluated in an age-dependent manner. We identified 13 proteins with altered levels and/or phosphorylation states that play key roles in various metabolic pathways including glycolysis, β-oxidation, the malate-aspartate shuttle, the Tricarboxylic Acid Cycle (TCA) cycle, the electron transport chain, NADPH production, as well as the production of glutamate. New insights into potential pathways involved in metabolic aspects of successful aging have been obtained by the identification of key proteins through which the NMR brain responds and adapts to the aging process and how the NMR brain adapted to resist age-related degeneration. This study examines the changes in the proteome and phosphoproteome in the brain of the naked mole-rat aged 2-24 years. We identified 13 proteins (labeled in red) with altered expression and/or phosphorylation levels that are conceivably associated with sustained metabolic functions in the oldest NMRs that may promote a sustained health span and life span.

  4. Variability of space-use patterns in a free living eusocial rodent, Ansell’s mole-rat indicates age-based rather than caste polyethism

    PubMed Central

    Šklíba, Jan; Lövy, Matěj; Burda, Hynek; Šumbera, Radim

    2016-01-01

    Eusocial species of African mole-rats live in groups cooperating on multiple tasks and employing division of labour. In captivity, individuals of the same group differ in cooperative contribution as well as in preference for a particular task. Both can be viewed as polyethism. However, little information is available from free-ranging mole-rats, which live in large burrow systems. We made an attempt to detect polyethism in the free-living Ansell’s mole-rat (Fukomys anselli) as differences in individuals’ space-use patterns. We radio-tracked 17 adults from five groups. Large individuals, including breeding males, spent more time inside the nest than smaller individuals. Breeding females were more often located <10 m from the nest in comparison to non-breeding females, who were relatively more often located 30–90 m and exclusively >90 m from the nest. One non-breeding female even conducted a brief intrusion into a neighbouring group’s territory via an open tunnel connection. A significant part of the variability in mole-rat space-use patterns was explained by body mass which is probably related to age in this species. This result can therefore be attributed to age polyethism. There was no apparent discontinuity in the space-use patterns of non-breeders that would indicate existence of castes. PMID:27922127

  5. Adenosine receptors mediate the hypoxic ventilatory response but not the hypoxic metabolic response in the naked mole rat during acute hypoxia

    PubMed Central

    Pamenter, Matthew E.; Dzal, Yvonne A.; Milsom, William K.

    2015-01-01

    Naked mole rats are the most hypoxia-tolerant mammals identified; however, the mechanisms underlying this tolerance are poorly understood. Using whole-animal plethysmography and open-flow respirometry, we examined the hypoxic metabolic response (HMR), hypoxic ventilatory response (HVR) and hypoxic thermal response in awake, freely behaving naked mole rats exposed to 7% O2 for 1 h. Metabolic rate and ventilation each reversibly decreased 70% in hypoxia (from 39.6 ± 2.9 to 12.1 ± 0.3 ml O2 min−1 kg−1, and 1412 ± 244 to 417 ± 62 ml min−1 kg−1, respectively; p < 0.05), whereas body temperature was unchanged and animals remained awake and active. Subcutaneous injection of the general adenosine receptor antagonist aminophylline (AMP; 100 mg kg−1, in saline), but not control saline injections, prevented the HVR but had no effect on the HMR. As a result, AMP-treated naked mole rats exhibited extreme hyperventilation in hypoxia. These animals were also less tolerant to hypoxia, and in some cases hypoxia was lethal following AMP injection. We conclude that in naked mole rats (i) hypoxia tolerance is partially dependent on profound hypoxic metabolic and ventilatory responses, which are equal in magnitude but occur independently of thermal changes in hypoxia, and (ii) adenosine receptors mediate the HVR but not the HMR. PMID:25520355

  6. Size variation in Tachyoryctes splendens (East African mole-rat) and its implications for late Quaternary temperature change in equatorial East Africa

    NASA Astrophysics Data System (ADS)

    Faith, J. Tyler; Patterson, David B.; Blegen, Nick; O'Neill, Chris J.; Marean, Curtis W.; Peppe, Daniel J.; Tryon, Christian A.

    2016-05-01

    This study develops a new proxy for Quaternary temperature change in tropical Africa through analysis of size variation in East African mole-rat (Tachyoryctes splendens). In modern mole-rats, mandibular alveolar length is unrelated to annual precipitation, precipitation seasonality, temperature seasonality, or primary productivity. However, it is inversely correlated with mean annual temperature, in agreement with Bergmann's rule. This relationship is observed at temperatures below ∼17.3 °C, but not at higher temperatures. We apply these observations to late Quaternary mole-rats from Wakondo (∼100 ka) and Kisaaka (∼50 ka) in the Lake Victoria region and Enkapune ya Muto (EYM; ∼7.2-3.2 ka) in Kenya's central rift. The Lake Victoria mole-rats are larger than expected for populations from warm climates typical of the area today, implying cooler temperatures in the past. The magnitude of temperature decline needed to drive the size shift is substantial (∼4-6 °C), similar in magnitude to the degree of change between the Last Glacial Maximum and Holocene, but is consistent with regional temperature records and with scenarios linking equatorial African temperature to northern hemisphere summer insolation. Size changes through time at EYM indicate that rising temperatures during the middle Holocene accompanied and potentially contributed to a decline in Lake Naivasha and expansion of grassland vegetation.

  7. Adenosine receptors mediate the hypoxic ventilatory response but not the hypoxic metabolic response in the naked mole rat during acute hypoxia.

    PubMed

    Pamenter, Matthew E; Dzal, Yvonne A; Milsom, William K

    2015-02-07

    Naked mole rats are the most hypoxia-tolerant mammals identified; however, the mechanisms underlying this tolerance are poorly understood. Using whole-animal plethysmography and open-flow respirometry, we examined the hypoxic metabolic response (HMR), hypoxic ventilatory response (HVR) and hypoxic thermal response in awake, freely behaving naked mole rats exposed to 7% O₂ for 1 h. Metabolic rate and ventilation each reversibly decreased 70% in hypoxia (from 39.6 ± 2.9 to 12.1 ± 0.3 ml O₂ min(-1) kg(-1), and 1412 ± 244 to 417 ± 62 ml min(-1) kg(-1), respectively; p < 0.05), whereas body temperature was unchanged and animals remained awake and active. Subcutaneous injection of the general adenosine receptor antagonist aminophylline (AMP; 100 mg kg(-1), in saline), but not control saline injections, prevented the HVR but had no effect on the HMR. As a result, AMP-treated naked mole rats exhibited extreme hyperventilation in hypoxia. These animals were also less tolerant to hypoxia, and in some cases hypoxia was lethal following AMP injection. We conclude that in naked mole rats (i) hypoxia tolerance is partially dependent on profound hypoxic metabolic and ventilatory responses, which are equal in magnitude but occur independently of thermal changes in hypoxia, and (ii) adenosine receptors mediate the HVR but not the HMR.

  8. Final report of CCQM-K129 Measurement of Mole Fractions of Cu, In, Ga and Se in Cu(In,Ga)Se2 Films

    NASA Astrophysics Data System (ADS)

    Kim, K. J.; Kim, A. S.; Jang, J. S.; Suh, J. K.; Wirth, T.; Unger, W.; Hodoroaba, V.-D.; Araujo, J. R.; Archanjo, B. S.; Galhardo, C. E.; Damasceno, J.; Achete, C. A.; Wang, H.; Wang, M.; Bennett, J.; Simon, D.; Kurokawa, A.; Terauchi, S.; Fujimoto, T.; Streeck, C.; Beckhoff, B.; Spencer, S.; Shard, A.

    2016-01-01

    CCQM key comparison K-129 for the quantitative analysis of Cu(In,Ga)Se2 (CIGS) films has been performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The objective of this key comparison is to compare the equivalency of the National Metrology Institutes (NMIs) and Designated Institutes (DIs) for the measurement of mole fractions of Cu, In, Ga and Se in a thin CIGS film. The measurand of this key comparison is the average mole fractions of Cu, In, Ga and Se of a test CIGS alloy film in the unit of mole fraction (mol/mol). Mole fraction with the metrological unit of % mol/mol can be practically converted to atomic fraction with the unit of at %. In this key comparison, a CIGS film with certified mole fractions was supplied as a reference specimen to determine the relative sensitivity factors (RSFs) of Cu, In, Ga and Se. The mole fractions of the reference specimen were certified by isotope dilution - inductively coupled plasma/mass spectrometry (ID-ICP/MS). A total number counting (TNC) method was recommended as a method to determine the signal intensities of the constituent elements acquired in the depth profiles by Secondary Ion Mass Spectrometry (SIMS), X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES). Seven NMIs and one DI participated in this key comparison. The mole fractions of the CIGS films were measured by depth profiling based-SIMS, AES and XPS. In this key comparison, the average degrees of equivalence uncertainties for Cu, In, Ga and Se are 0.0093 mol/mol, 0.0123 mol/mol, 0.0047 mol/mol and 0.0228 mol/mol, respectively. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  9. INK4 locus of the tumor-resistant rodent, the naked mole rat, expresses a functional p15/p16 hybrid isoform.

    PubMed

    Tian, Xiao; Azpurua, Jorge; Ke, Zhonghe; Augereau, Adeline; Zhang, Zhengdong D; Vijg, Jan; Gladyshev, Vadim N; Gorbunova, Vera; Seluanov, Andrei

    2015-01-27

    The naked mole rat (Heterocephalus glaber) is a long-lived and tumor-resistant rodent. Tumor resistance in the naked mole rat is mediated by the extracellular matrix component hyaluronan of very high molecular weight (HMW-HA). HMW-HA triggers hypersensitivity of naked mole rat cells to contact inhibition, which is associated with induction of the INK4 (inhibitors of cyclin dependent kinase 4) locus leading to cell-cycle arrest. The INK4a/b locus is among the most frequently mutated in human cancer. This locus encodes three distinct tumor suppressors: p15(INK4b), p16(INK4a), and ARF (alternate reading frame). Although p15(INK4b) has its own ORF, p16(INK4a) and ARF share common second and third exons with alternative reading frames. Here, we show that, in the naked mole rat, the INK4a/b locus encodes an additional product that consists of p15(INK4b) exon 1 joined to p16(INK4a) exons 2 and 3. We have named this isoform pALT(INK4a/b) (for alternative splicing). We show that pALT(INK4a/b) is present in both cultured cells and naked mole rat tissues but is absent in human and mouse cells. Additionally, we demonstrate that pALT(INK4a/b) expression is induced during early contact inhibition and upon a variety of stresses such as UV, gamma irradiation-induced senescence, loss of substrate attachment, and expression of oncogenes. When overexpressed in naked mole rat or human cells, pALT(INK4a/b) has stronger ability to induce cell-cycle arrest than either p15(INK4b) or p16(INK4a). We hypothesize that the presence of the fourth product, pALT(INK4a/b) of the INK4a/b locus in the naked mole rat, contributes to the increased resistance to tumorigenesis of this species.

  10. Effects of laboratory housing on exploratory behaviour, novelty discrimination and spatial reference memory in a subterranean, solitary rodent, the Cape mole-rat (Georychus capensis).

    PubMed

    Oosthuizen, Maria Kathleen; Scheibler, Anne-Gita; Bennett, Nigel Charles; Amrein, Irmgard

    2013-01-01

    A large number of laboratory and field based studies are being carried out on mole-rats, both in our research group and others. Several studies have highlighted the development of adverse behaviours in laboratory animals and have emphasised the importance of enrichment for captive animals. Hence we were interested in evaluating how laboratory housing would affect behavioural performance in mole-rats. We investigated exploratory behaviour, the ability to discriminate between novel and familiar environments and reference memory in the solitary Cape mole-rat (Georychus capensis). Our data showed that both wild and captive animals readily explore open spaces and tunnels. Wild animals were however more active than their captive counterparts. In the Y maze two trial discrimination task, wild animals failed to discriminate between novel and familiar environments, while laboratory housed mole-rats showed preferential spatial discrimination in terms of the length of time spent in the novel arm. The performance of the laboratory and wild animals were similar when tested for reference memory in the Y maze, both groups showed a significant improvement compared to the first day, from the 3rd day onwards. Wild animals made more mistakes whereas laboratory animals were slower in completing the task. The difference in performance between wild and laboratory animals in the Y-maze may be as a result of the lower activity of the laboratory animals. Laboratory maintained Cape mole-rats show classic behaviours resulting from a lack of stimulation such as reduced activity and increased aggression. However, they do display an improved novelty discrimination compared to the wild animals. Slower locomotion rate of the laboratory animals may increase the integration time of stimuli, hence result in a more thorough inspection of the surroundings. Unlike the captive animals, wild animals show flexibility in their responses to unpredictable events, which is an important requirement under

  11. Specific Paucity of Unmyelinated C-Fibers in Cutaneous Peripheral Nerves of the African Naked-Mole Rat: Comparative Analysis Using Six Species of Bathyergidae

    PubMed Central

    Smith, Ewan S; Purfürst, Bettina; Grigoryan, Tamara; Park, Thomas J; Bennett, Nigel C; Lewin, Gary R

    2012-01-01

    In mammalian peripheral nerves, unmyelinated C-fibers usually outnumber myelinated A-fibers. By using transmission electron microscopy, we recently showed that the saphenous nerve of the naked mole-rat (Heterocephalus glaber) has a C-fiber deficit manifested as a substantially lower C:A-fiber ratio compared with other mammals. Here we determined the uniqueness of this C-fiber deficit by performing a quantitative anatomical analysis of several peripheral nerves in five further members of the Bathyergidae mole-rat family: silvery (Heliophobius argenteocinereus), giant (Fukomys mechowii), Damaraland (Fukomys damarensis), Mashona (Fukomys darlingi), and Natal (Cryptomys hottentotus natalensis) mole-rats. In the largely cutaneous saphenous and sural nerves, the naked mole-rat had the lowest C:A-fiber ratio (∼1.5:1 compared with ∼3:1), whereas, in nerves innervating both skin and muscle (common peroneal and tibial) or just muscle (lateral/medial gastrocnemius), this pattern was mostly absent. We asked whether lack of hair follicles alone accounts for the C-fiber paucity by using as a model a mouse that loses virtually all its hair as a consequence of conditional deletion of the β-catenin gene in the skin. These β-catenin loss-of function mice (β-cat LOF mice) displayed only a mild decrease in C:A-fiber ratio compared with wild-type mice (4.42 compared with 3.81). We suggest that the selective cutaneous C-fiber deficit in the cutaneous nerves of naked mole-rats is unlikely to be due primarily to lack of skin hair follicles. Possible mechanisms contributing to this unique peripheral nerve anatomy are discussed. J. Comp. Neurol. 520:2785–2803, 2012. © 2012 Wiley Periodicals, Inc. PMID:22528859

  12. Altered composition of liver proteasome assemblies contributes to enhanced proteasome activity in the exceptionally long-lived naked mole-rat.

    PubMed

    Rodriguez, Karl A; Edrey, Yael H; Osmulski, Pawel; Gaczynska, Maria; Buffenstein, Rochelle

    2012-01-01

    The longest-lived rodent, the naked mole-rat (Bathyergidae; Heterocephalus glaber), maintains robust health for at least 75% of its 32 year lifespan, suggesting that the decline in genomic integrity or protein homeostasis routinely observed during aging, is either attenuated or delayed in this extraordinarily long-lived species. The ubiquitin proteasome system (UPS) plays an integral role in protein homeostasis by degrading oxidatively-damaged and misfolded proteins. In this study, we examined proteasome activity in naked mole-rats and mice in whole liver lysates as well as three subcellular fractions to probe the mechanisms behind the apparently enhanced effectiveness of UPS. We found that when compared with mouse samples, naked mole-rats had significantly higher chymotrypsin-like (ChT-L) activity and a two-fold increase in trypsin-like (T-L) in both whole lysates as well as cytosolic fractions. Native gel electrophoresis of the whole tissue lysates showed that the 20S proteasome was more active in the longer-lived species and that 26S proteasome was both more active and more populous. Western blot analyses revealed that both 19S subunits and immunoproteasome catalytic subunits are present in greater amounts in the naked mole-rat suggesting that the observed higher specific activity may be due to the greater proportion of immunoproteasomes in livers of healthy young adults. It thus appears that proteasomes in this species are primed for the efficient removal of stress-damaged proteins. Further characterization of the naked mole-rat proteasome and its regulation could lead to important insights on how the cells in these animals handle increased stress and protein damage to maintain a longer health in their tissues and ultimately a longer life.

  13. Dental peculiarities in the silvery mole-rat: an original model for studying the evolutionary and biological origins of continuous dental generation in mammals

    PubMed Central

    Šumbera, Radim

    2015-01-01

    Unravelling the evolutionary and developmental mechanisms that have impacted the mammalian dentition, since more than 200 Ma, is an intricate issue. Interestingly, a few mammal species, including the silvery mole-rat Heliophobius argenteocinereus, are able to replace their dentition by the addition of supernumerary molars at the back of jaw migrating then toward the front. The aim here was to demonstrate the potential interest of further studying this rodent in order to better understand the origins of continuous dental replacement in mammals, which could also provide interesting data concerning the evolution of limited dental generation occurring in first mammals. In the present study, we described the main stages of the dental eruptive sequence in the silvery mole-rat and the associated characteristics of horizontal replacement using X-ray microtomography. This was coupled to the investigation of other African mole-rats which have no dental replacement. This method permitted to establish evidence that the initial development of the dentition in Heliophobius is comparable to what it is observed in most of African mole-rats. This rodent first has premolars, but then identical additional molars, a mechanism convergent to manatees and the pygmy rock-wallaby. Evidence of continuous replacement and strong dental dynamics were also illustrated in Heliophobius, and stressed the need to deeply investigate these aspects for evolutionary, functional and developmental purposes. We also noticed that two groups of extinct non-mammalian synapsids convergently acquired this dental mechanism, but in a way differing from extant mammals. The discussion on the diverse evolutionary origins of horizontal dental replacement put emphasis on the necessity of focusing on biological parameters potentially involved in both continuous and limited developments of teeth in mammals. In that context, the silvery mole-rat could appear as the most appropriate candidate to do so. PMID:26401449

  14. Pronounced cancer resistance in a subterranean rodent, the blind mole-rat, Spalax: in vivo and in vitro evidence

    PubMed Central

    2013-01-01

    Background Subterranean blind mole rats (Spalax) are hypoxia tolerant (down to 3% O2), long lived (>20 years) rodents showing no clear signs of aging or aging related disorders. In 50 years of Spalax research, spontaneous tumors have never been recorded among thousands of individuals. Here we addressed the questions of (1) whether Spalax is resistant to chemically-induced tumorigenesis, and (2) whether normal fibroblasts isolated from Spalax possess tumor-suppressive activity. Results Treating animals with 3-Methylcholantrene (3MCA) and 7,12-Dimethylbenz(a) anthracene/12-O-tetradecanoylphorbol-13-acetate (DMBA/TPA), two potent carcinogens, confirmed Spalax high resistance to chemically induced cancers. While all mice and rats developed the expected tumors following treatment with both carcinogens, among Spalax no tumors were observed after DMBA/TPA treatment, while 3MCA induced benign fibroblastic proliferation in 2 Spalax individuals out of12, and only a single animal from the advanced age group developed malignancy 18 months post-treatment. The remaining animals are still healthy 30 months post-treatment. In vitro experiments showed an extraordinary ability of normal Spalax cultured fibroblasts to restrict malignant behavior in a broad spectrum of human-derived and in newly isolated Spalax 3MCA-induced cancer cell lines. Growth of cancer cells was inhibited by either direct interaction with Spalax fibroblasts or with soluble factors released into culture media and soft agar. This was accompanied by decreased cancer cell viability, reduced colony formation in soft agar, disturbed cell cycle progression, chromatin condensation and mitochondrial fragmentation. Cells from another cancer resistant subterranean mammal, the naked mole rat, were also tested for direct effect on cancer cells and, similar to Spalax, demonstrated anti-cancer activity. No effect on cancer cells was observed using fibroblasts from mouse, rat or Acomys. Spalax fibroblast conditioned media had

  15. Evolution of bone compactness in extant and extinct moles (Talpidae): exploring humeral microstructure in small fossorial mammals

    PubMed Central

    2013-01-01

    Background Talpids include forms with different degree of fossoriality, with major specializations in the humerus in the case of the fully fossorial moles. We studied the humeral microanatomy of eleven extant and eight extinct talpid taxa of different lifestyles and of two non-fossorial outgroups and examined the effects of size and phylogeny. We tested the hypothesis that bone microanatomy is different in highly derived humeri of fossorial taxa than in terrestrial and semi-aquatic ones, likely due to special mechanical strains to which they are exposed to during digging. This study is the first comprehensive examination of histological parameters in an ecologically diverse and small-sized mammalian clade. Results No pattern of global bone compactness was found in the humeri of talpids that could be related to biomechanical specialization, phylogeny or size. The transition zone from the medullary cavity to the cortical compacta was larger and the ellipse ratio smaller in fossorial talpids than in non-fossorial talpids. No differences were detected between the two distantly related fossorial clades, Talpini and Scalopini. Conclusions At this small size, the overall morphology of the humerus plays a predominant role in absorbing the load, and microanatomical features such as an increase in bone compactness are less important, perhaps due to insufficient gravitational effects. The ellipse ratio of bone compactness shows relatively high intraspecific variation, and therefore predictions from this ratio based on single specimens are invalid. PMID:23442022

  16. Twin pregnancy and partial hydatidiform mole following in vitro fertilization and embryos transfer: a novel case of placental mosaicism.

    PubMed

    Sun, Cheng-juan; Zhao, You-ping; Yu, Song; Fan, Ling; Wu, Qing-qing; Li, Guang-hui; Zhang, Wei-yuan

    2012-12-01

    Twin pregnancy with mosaic partial hydatidiform mole (PHM) and survival of two healthy fetuses following in vitro fertilization and embryos transfer (IVF-ET) is a rare situation and is considered a challenge for management. A 32-year-old Chinese woman conceived twin pregnancy following IVF-ET. At 22 weeks' gestation, an additional intrauterine echogenic mass with features of PHM were shown by successive ultrasound examinations. At 35 weeks' gestation, two live male infants and two placentas were delivered by caesarean section (CS). Histologic examination of the abnormal placenta confirmed mosaic PHM. Genetic study showed the abnormal placental mosaicism (expressed in molar-69XXY and normal vili-46XY), co-existing with a hypospadia new-born (46XY) in one amniotic sac. However, the other one was normal. Serial serum β-hCG levels showed a declining trend and serum β-human chorionic gonadotropin (hCG) were undetectable at 6 months after delivery. The case demonstrated that it is possible to prolonged gestation by PHM under close surveillance during the entire pregnancy.

  17. A distinct role of the queen in coordinated workload and soil distribution in eusocial naked mole-rats.

    PubMed

    Kutsukake, Nobuyuki; Inada, Masayuki; Sakamoto, Shinsuke H; Okanoya, Kazuo

    2012-01-01

    We investigated how group members achieve collective decision-making, by considering individual intrinsic behavioural rules and behavioural mechanisms for maintaining social integration. Using a simulated burrow environment, we investigated the behavioural rules of coordinated workload for soil distribution in a eusocial mammal, the naked mole-rat (Heterocephalus glaber). We tested two predictions regarding a distinct role of the queen, a socially dominant individual in the caste system: the presence of a queen would increase the workload of other caste individuals, and the cues by a queen would affect the soil distribution. In experiment 1, we placed four individuals of various castes from the same colony into an experimental burrow. Workers exhibited the highest frequency of workload compared to other castes. The presence of a queen activated the workload by other individuals. Individuals showed a consistent workload in a particular direction so as to bias the soil distribution. These results suggest that individuals have a consensus on soil distribution and that the queen plays a distinct role. In experiment 2, we placed the odour of a queen in one of four cells and observed its effect on other individuals' workload and soil distribution. Relative to other cells, individuals frequently dug in the queen cell so the amount of soil in the queen cell decreased. These results suggest that queen odour is an important cue in coordinated workload and soil distribution in this species.

  18. Brain structure volumes in the mole rat, Spalax ehrenbergi (Spalacidae, Rodentia) in comparison to the rat and subterrestrial insectivores.

    PubMed

    Frahm, H D; Rehkämper, G; Nevo, E

    1997-01-01

    Natural blindness and a subterranean, digging mode of life demand peculiar adaptations of the central nervous system in the mole rat Spalax ehrenbergi, which are the focus of this quantitative investigation. Volumes of 25 brain structures in Spalax were evaluated allometrically, using the least encephalized mammalian species, the Madagassian hedgehog-like tenrecs (Tenrecinae) as a reference base, and their sizes compared with those of the rat (as a more generalized representative of rodents) and of some subterranean Insectivora. The allometric approach reveals that Spalax has a larger brain than tenrecs and the rat. Within the brain, the neocortex and diencephalon are well developed, an observation also made in other mammalian species with a relatively high encephalization. An unique feature in Spalax is the enlargement of motor structures of the brain, such as the cerebellum (and cerebellar nuclei), and the striatum. Most conspicuous is the large size of the nucleus motorius nervi trigemini, reflecting the importance of masticatory muscles for the special digging technique, which demand an intense use of the teeth for loosening the soil.

  19. Seasonality and interannual variability of CH4 fluxes from the eastern Amazon Basin inferred from atmospheric mole fraction profiles

    NASA Astrophysics Data System (ADS)

    Basso, Luana S.; Gatti, Luciana V.; Gloor, Manuel; Miller, John B.; Domingues, Lucas G.; Correia, Caio S. C.; Borges, Viviane F.

    2016-01-01

    The Amazon Basin is an important region for global CH4 emissions. It hosts the largest area of humid tropical forests, and around 20% of this area is seasonally flooded. In a warming climate it is possible that CH4 emissions from the Amazon will increase both as a result of increased temperatures and precipitation. To examine if there are indications of first signs of such changes we present here a 13 year (2000-2013) record of regularly measured vertical CH4 mole fraction profiles above the eastern Brazilian Amazon, sensitive to fluxes from the region upwind of Santarém (SAN), between SAN and the Atlantic coast. Using a simple mass balance approach, we find substantial CH4 emissions with an annual average flux of 52.8 ± 6.8 mg CH4 m-2 d-1 over an area of approximately 1 × 106 km2. Fluxes are highest in two periods of the year: in the beginning of the wet season and during the dry season. Using a CO:CH4 emission factor estimated from the profile data, we estimated a contribution of biomass burning of around 15% to the total flux in the dry season, indicating that biogenic emissions dominate the CH4 flux. This 13 year record shows that CH4 emissions upwind of SAN varied over the years, with highest emissions in 2008 (around 25% higher than in 2007), mainly during the wet season, representing 19% of the observed global increase in this year.

  20. A Distinct Role of the Queen in Coordinated Workload and Soil Distribution in Eusocial Naked Mole-Rats

    PubMed Central

    Kutsukake, Nobuyuki; Inada, Masayuki; Sakamoto, Shinsuke H.; Okanoya, Kazuo

    2012-01-01

    We investigated how group members achieve collective decision-making, by considering individual intrinsic behavioural rules and behavioural mechanisms for maintaining social integration. Using a simulated burrow environment, we investigated the behavioural rules of coordinated workload for soil distribution in a eusocial mammal, the naked mole-rat (Heterocephalus glaber). We tested two predictions regarding a distinct role of the queen, a socially dominant individual in the caste system: the presence of a queen would increase the workload of other caste individuals, and the cues by a queen would affect the soil distribution. In experiment 1, we placed four individuals of various castes from the same colony into an experimental burrow. Workers exhibited the highest frequency of workload compared to other castes. The presence of a queen activated the workload by other individuals. Individuals showed a consistent workload in a particular direction so as to bias the soil distribution. These results suggest that individuals have a consensus on soil distribution and that the queen plays a distinct role. In experiment 2, we placed the odour of a queen in one of four cells and observed its effect on other individuals’ workload and soil distribution. Relative to other cells, individuals frequently dug in the queen cell so the amount of soil in the queen cell decreased. These results suggest that queen odour is an important cue in coordinated workload and soil distribution in this species. PMID:22957085

  1. A microfluidic platform for transcription- and amplification-free detection of zepto-mole amounts of nucleic acid molecules.

    PubMed

    Mayr, Reinhard; Haider, Michaela; Thünauer, Roland; Haselgrübler, Thomas; Schütz, Gerhard J; Sonnleitner, Alois; Hesse, Jan

    2016-04-15

    Here we report the development of a device for the transcription- and amplification-free detection of DNA and RNA molecules down to the zepto-mole range. A microfluidic chip with a built-in microarray was used for manipulation of nano-liter sample volumes. Specific staining and immobilization of the target molecules was achieved via a double hybridization approach thereby avoiding bias due to enzymatic processes like reverse transcription and PCR amplification. Therefore, target molecules were indirectly labeled by pre-hybridization to complementary Cy5-labeled probes. The remaining single-stranded portion of each target molecule could subsequently hybridize to complementary capture probes of a microarray. Thus a target-mediated immobilization of labeled DNA took place. By means of an ultra-sensitive fluorescence readout, all molecules hybridized to the microarray could be detected. The combination of minimized sample volume and single molecule detection yielded a detection limit of 39 fM (831 molecules in 35.4 nl assay volume) for target DNA and 16 fM (338 molecules) for target RNA after 1h on-chip hybridization.

  2. A new species of Argyromys (Rodentia, Mammalia) from the Oligocene of the Valley of Lakes (Mongolia): Its importance for palaeobiogeographical homogeneity across Mongolia, China and Kazakhstan

    PubMed Central

    Maridet, Olivier; Zhang, Zhaoqun; Daxner-Höck, Gudrun

    2017-01-01

    We describe a new species of Rodentia (Mammalia), Argyromys cicigei sp. nov. from Toglorhoi (fossil bed TGW-A/2a) in Mongolia and Ulantatal (fossil beds UTL 1 and UTL 7) in China. Its tooth morphology differs from the type species Argyromys aralensis from Akespe in Kazakhstan by smaller size and simpler structures. Argyromys has been assigned in different families of Muroidea, such as Tachyoryctoididae and Spalacidae. However, the presence of common characters indicates a closer relationship of Argyromys with the genera of Cricetidae s.l. (subfamilies Eucricetodontinae; Cricetopinae; Cricetodontinae and Gobicricetodontinae among others) from Asia than with the earliest representatives of Spalacidae or the endemic Tachyoryctoididae. Argyromys cicigei sp. nov. possesses a simple anterocone and anteroconid in the upper and lower first molars, respectively, which is characteristic for Cricetidae s.l. It has a flat occlusal surface in worn specimens; weakly-developed posterolophs; an oblique protolophule and metaloph on the upper molars and it lacks a labial anterolophid on the m1. These traits are also typical of the Oligocene genera Aralocricetodon and Plesiodipus, included in the subfamilies Cricetodontinae and Gobicricetodontinae respectively. The cladistic analysis performed here supports this hypothesis. The clade formed by Argyromys species is grouped with other cricetid taxa (s.l). Spalacids, however, form a different clade, as do the tachyoryctoids. Previous authors state that the Aral Formation (Kazakhstan) should be dated to the Oligocene instead of the Miocene, based on the presence of several taxa. The finds of Argyromys in both regions supports the statement that they are closer in age than previously thought. The occurrence of Argyromys in Kazakhstan, Mongolia and China evidences the biogeographic unity of the Central Asian bioprovince during the Oligocene. PMID:28328975

  3. A new species of Argyromys (Rodentia, Mammalia) from the Oligocene of the Valley of Lakes (Mongolia): Its importance for palaeobiogeographical homogeneity across Mongolia, China and Kazakhstan.

    PubMed

    López-Guerrero, Paloma; Maridet, Olivier; Zhang, Zhaoqun; Daxner-Höck, Gudrun

    2017-01-01

    We describe a new species of Rodentia (Mammalia), Argyromys cicigei sp. nov. from Toglorhoi (fossil bed TGW-A/2a) in Mongolia and Ulantatal (fossil beds UTL 1 and UTL 7) in China. Its tooth morphology differs from the type species Argyromys aralensis from Akespe in Kazakhstan by smaller size and simpler structures. Argyromys has been assigned in different families of Muroidea, such as Tachyoryctoididae and Spalacidae. However, the presence of common characters indicates a closer relationship of Argyromys with the genera of Cricetidae s.l. (subfamilies Eucricetodontinae; Cricetopinae; Cricetodontinae and Gobicricetodontinae among others) from Asia than with the earliest representatives of Spalacidae or the endemic Tachyoryctoididae. Argyromys cicigei sp. nov. possesses a simple anterocone and anteroconid in the upper and lower first molars, respectively, which is characteristic for Cricetidae s.l. It has a flat occlusal surface in worn specimens; weakly-developed posterolophs; an oblique protolophule and metaloph on the upper molars and it lacks a labial anterolophid on the m1. These traits are also typical of the Oligocene genera Aralocricetodon and Plesiodipus, included in the subfamilies Cricetodontinae and Gobicricetodontinae respectively. The cladistic analysis performed here supports this hypothesis. The clade formed by Argyromys species is grouped with other cricetid taxa (s.l). Spalacids, however, form a different clade, as do the tachyoryctoids. Previous authors state that the Aral Formation (Kazakhstan) should be dated to the Oligocene instead of the Miocene, based on the presence of several taxa. The finds of Argyromys in both regions supports the statement that they are closer in age than previously thought. The occurrence of Argyromys in Kazakhstan, Mongolia and China evidences the biogeographic unity of the Central Asian bioprovince during the Oligocene.

  4. A new species of Neosclerocalyptus Paula Couto (Mammalia: Xenarthra: Cingulata): the oldest record of the genus and morphological and phylogenetic aspects.

    PubMed

    Zurita, Alfredo E; Taglioretti, Matias; Zamorano, Martin; Scillato-Yané, Gustavo J; Luna, Carlos; Boh, Daniel; Saffer, Mariano Magnussen

    2013-01-01

    Among South American Quaternary Glyptodontidae (Mammalia, Cingulata), Neosclerocalyptus Paula Couto represents one of the best known genera. Prior to this contribution, four species were recognized. N. pseudornatus (Ameghino) and N. ornatus (Owen) (Ensenadan Age/Stage, early-middle Pleistocene); N. gouldi Zurita (Bonaerian Age/Stage, middle Pleistocene-late Pleistocene), and N. paskoensis (Zurita) (Lujanian Age/Stage, late Pleistocene-early Holocene). One of the most notable characters of the species of the genus is a modified area located in the distal part of the nasals, recently interpreted as a neomorphic structure derived from the ossification of the nasal cartilages. In this contribution, a new species of Neosclerocalyptus (N. castellanosi sp. nov.), which in turn represents the oldest record of the genus, is presented and described. In addition, a cladistic analysis is carried out to test the monophyly of Neosclerocalyptus and the phylogenetic position of this new species. The material comes from Vorohuean (late Pliocene) levels in the surroundings of Mar del Plata, Buenos Aires Province, Argentina. Among other morphological characters, this new species has ossified nasal cartilages restricted to the latero-dorsal area of the nasals, whereas in the remaining species these structures are more expanded and both sides contact in the midline of the skull. In turn, the phylogenetic analysis confirmed the monophyly of Neosclerocalyptus, whereas N. castellanosi sp. nov. appears closely related to N. pseudornatus, being N. ornatus the sister taxa of this clade. On the other hand, N. gouldi + N. paskoensis constitute the other clade. The clade constituted by Hoplophorus euphractus Lund + Panochthus intermedius Lydekker constitutes the sister taxa of Neosclerocalyptus.

  5. Antigenic and genotypic characterization of rabies virus isolated from bats (Mammalia: Chiroptera) from municipalities in São Paulo State, Southeastern Brazil.

    PubMed

    Menozzi, Benedito Donizete; de Novaes Oliveira, Rafael; Paiz, Laís Moraes; Richini-Pereira, Virgínia Bodelão; Langoni, Helio

    2017-01-20

    Bats have aroused growing attention in the public health sphere because they are considered the main reservoir of rabies virus (RABV) in the Americas, in places where canine rabies is under control. Antigenic and genetic studies of RABV isolates have been used to describe the epidemiological profile of rabies and to identify possible hosts/reservoirs for different epidemiological cycles. This study describes the antigenic and genotypic characterization of 19 RABV isolates from central nervous system samples of non-hematophagous bats (Mammalia: Chiroptera). These bats were diagnosed as RABV positive by direct fluorescent antibody and mouse inoculation tests. Antigenic characterization using a panel of eight monoclonal antibodies revealed that 7 of 19 RABV isolates from these bats belonged to variant 3, for which the hematophagous bat species Desmodus rotundus is the main reservoir, and 1 of 19 RABV isolates from an insectivorous bat belonged to variant 4, which is characteristic of these bats. The remaining 11 RABV samples were divided into six non-compatible profiles. The isolates were subjected to reverse transcription polymerase chain reaction for the N gene and partially sequenced. Genetic characterization of these isolates was performed by grouping the sequences obtained with known RABV lineages. The sequences were grouped in clusters by the phylogenetic inference neighbor-joining method, together with another 89 homologous sequences obtained from GenBank. This analysis grouped the isolates into four known lineages: Nyctinomops Brazil, Myotis Brazil, Eptesicus Brazil and D. rotundus Brazil, as well as another cluster that may define a RABV lineage not yet characterized, here named Myotis Brazil II, for which bats of the genus Myotis apparently act as reservoirs. This assumption of a new lineage is also based on the observation of amino acid substitutions, with an average intraspecific identity of 99.8%, varying from 99.6 to 100.0% for nucleotides and 100

  6. Body Mole Map

    MedlinePlus

    ... ETECT. PREVENT Skin Cancer: Protect Yourself From the Sun Sun exposure is the most preventable risk factor for ... including melanoma. You can have fun in the sun and decrease your risk of skin cancer. NT. ...

  7. Non-Breeding Eusocial Mole-Rats Produce Viable Sperm—Spermiogram and Functional Testicular Morphology of Fukomys anselli

    PubMed Central

    Garcia Montero, Angelica; Vole, Christiane; Burda, Hynek; Malkemper, Erich Pascal; Holtze, Susanne; Morhart, Michaela; Saragusty, Joseph; Hildebrandt, Thomas B.; Begall, Sabine

    2016-01-01

    Ansell’s mole-rats (Fukomys anselli) are subterranean rodents living in families composed of about 20 members with a single breeding pair and their non-breeding offspring. Most of them remain with their parents for their lifetime and help to maintain and defend the natal burrow system, forage, and care for younger siblings. Since incest avoidance is based on individual recognition (and not on social suppression) we expect that non-breeders produce viable sperm spontaneously. We compared the sperm of breeding and non-breeding males, obtained by electroejaculation and found no significant differences in sperm parameters between both groups. Here, we used electroejaculation to obtain semen for the first time in a subterranean mammal. Spermiogram analysis revealed no significant differences in sperm parameters between breeders and non-breeders. We found significantly larger testes (measured on autopsies and on living animals per ultrasonography) of breeders compared to non-breeders (with body mass having a significant effect). There were no marked histological differences between breeding and non-breeding males, and the relative area occupied by Leydig cells and seminiferous tubules on histological sections, respectively, was not significantly different between both groups. The seminiferous epithelium and to a lesser degree the interstitial testicular tissue are characterized by lesions (vacuolar degenerations), however, this feature does not hinder fertilization even in advanced stages of life. The continuous production of viable sperm also in sexually abstinent non-breeders might be best understood in light of the mating and social system of Fukomys anselli, and the potential to found a new family following an unpredictable and rare encounter with an unfamiliar female (“provoked or induced dispersal”). Apparently, the non-breeders do not reproduce because they do not copulate but not because they would be physiologically infertile. The significantly increased

  8. Seasonality and interannual variability of CH4 fluxes from the eastern Amazon Basin inferred from atmospheric mole fraction profiles

    PubMed Central

    Gatti, Luciana V.; Gloor, Manuel; Miller, John B.; Domingues, Lucas G.; Correia, Caio S. C.; Borges, Viviane F.

    2016-01-01

    Abstract The Amazon Basin is an important region for global CH4 emissions. It hosts the largest area of humid tropical forests, and around 20% of this area is seasonally flooded. In a warming climate it is possible that CH4 emissions from the Amazon will increase both as a result of increased temperatures and precipitation. To examine if there are indications of first signs of such changes we present here a 13 year (2000–2013) record of regularly measured vertical CH4 mole fraction profiles above the eastern Brazilian Amazon, sensitive to fluxes from the region upwind of Santarém (SAN), between SAN and the Atlantic coast. Using a simple mass balance approach, we find substantial CH4 emissions with an annual average flux of 52.8 ± 6.8 mg CH4 m−2 d−1 over an area of approximately 1 × 106 km2. Fluxes are highest in two periods of the year: in the beginning of the wet season and during the dry season. Using a CO:CH4 emission factor estimated from the profile data, we estimated a contribution of biomass burning of around 15% to the total flux in the dry season, indicating that biogenic emissions dominate the CH4 flux. This 13 year record shows that CH4 emissions upwind of SAN varied over the years, with highest emissions in 2008 (around 25% higher than in 2007), mainly during the wet season, representing 19% of the observed global increase in this year. PMID:27642546

  9. Seasonality and interannual variability of CH4 fluxes from the eastern Amazon Basin inferred from atmospheric mole fraction profiles.

    PubMed

    Basso, Luana S; Gatti, Luciana V; Gloor, Manuel; Miller, John B; Domingues, Lucas G; Correia, Caio S C; Borges, Viviane F

    2016-01-16

    The Amazon Basin is an important region for global CH4 emissions. It hosts the largest area of humid tropical forests, and around 20% of this area is seasonally flooded. In a warming climate it is possible that CH4 emissions from the Amazon will increase both as a result of increased temperatures and precipitation. To examine if there are indications of first signs of such changes we present here a 13 year (2000-2013) record of regularly measured vertical CH4 mole fraction profiles above the eastern Brazilian Amazon, sensitive to fluxes from the region upwind of Santarém (SAN), between SAN and the Atlantic coast. Using a simple mass balance approach, we find substantial CH4 emissions with an annual average flux of 52.8 ± 6.8 mg CH4 m(-2) d(-1) over an area of approximately 1 × 10(6) km(2). Fluxes are highest in two periods of the year: in the beginning of the wet season and during the dry season. Using a CO:CH4 emission factor estimated from the profile data, we estimated a contribution of biomass burning of around 15% to the total flux in the dry season, indicating that biogenic emissions dominate the CH4 flux. This 13 year record shows that CH4 emissions upwind of SAN varied over the years, with highest emissions in 2008 (around 25% higher than in 2007), mainly during the wet season, representing 19% of the observed global increase in this year.

  10. Petrosal anatomy in the fossil mammal Necrolestes: evidence for metatherian affinities and comparisons with the extant marsupial mole

    PubMed Central

    Ladevèze, Sandrine; Asher, Robert J; Sánchez-Villagra, Marcelo R

    2008-01-01

    We present reconstructions of petrosal anatomy based on high-resolution X-ray computed tomography scans for the fossil mammal Necrolestes and for the marsupial mole Notoryctes sp. Compared with other mammals, Necrolestes exhibits a mosaic of plesiomorphic and derived characters, but most of the evidence supports its metatherian status. We revised previous descriptions and report on features of phylogenetic or functional significance. Necrolestes exhibits features that support metatherian affinities, such as the presence of a short and lateral prootic canal, and the loss of the stapedial artery in adults. A deep groove at the anterior pole of the promontorium is present in front of the cochlear housing, a variant on the extrabullar pathway of the internal carotid artery. The promontorium is laterally bordered by a large bony projection resembling the eutherian tegmen tympani [De Beer GR (1937) The Development of the Vertebrate Skull, Oxford, Clarendon Press, p. 391]. Posteromedial to the secondary facial foramen and anterolateral to the fenestra vestibuli is a pronounced fossa for the tensor tympani muscle. On the medial part of the pars canalicularis there is a great inflation of the medial side of the caudal tympanic process, a structure of unknown function. The internal acoustic meatus exhibits a broad transverse septum and is bordered laterally by a broad prefacial commissure. The cochleae of Necrolestes and of Notoryctes have fewer spiral turns (1.1 and 1.6, respectively) than most marsupials. The lateral semicircular canal is more expanded than the posterior semicircular canal in Necrolestes but not in Notoryctes. Both Necrolestes and Notoryctes have a second crus commune, i.e. the lateral semicircular canal opens into the ampulla of the posterior semicircular canal. A stylomastoid foramen enclosed anterodorsally by both the pars cochlearis and pars canalicularis is present in Dasyuridae, Dromiciops gliroides and Notoryctes. PMID:19094184

  11. Immunohistochemical Characterization of the Chemosensory Pulmonary Neuroepithelial Bodies in the Naked Mole-Rat Reveals a Unique Adaptive Phenotype

    PubMed Central

    Pan, Jie; Park, Thomas J.; Cutz, Ernest; Yeger, Herman

    2014-01-01

    The pulmonary neuroepithelial bodies (NEBs) constitute polymodal airway chemosensors for monitoring and signaling ambient gas concentrations (pO2, pCO2/H+) via complex innervation to the brain stem controlling breathing. NEBs produce the bioactive amine, serotonin (5-HT), and a variety of peptides with multiple effects on lung physiology and other organ systems. NEBs in mammals appear prominent and numerous during fetal and neonatal periods, and decline in the post-natal period suggesting an important role during perinatal adaptation. The naked mole-rat (NMR), Heterocephalus glaber, has adapted to the extreme environmental conditions of living in subterranean burrows in large colonies (up to 300 colony mates). The crowded, unventilated burrows are environments of severe hypoxia and hypercapnia. However, NMRs adjust readily to above ground conditions. The chemosensory NEBs of this species were characterized and compared to those of the conventional Wistar rat (WR) to identify similarities and differences that could explain the NMR’s adaptability to environments. A multilabel immunohistochemical analysis combined with confocal microscopy revealed that the expression patterns of amine, peptide, neuroendocrine, innervation markers and chemosensor component proteins in NEBs of NMR were similar to that of WR. However, we found the following differences: 1) NEBs in both neonatal and adult NMR lungs were significantly larger and more numerous as compared to WR; 2) NEBs in NMR had a more variable compact cell organization and exhibited significant differences in the expression of adhesion proteins; 3) NMR NEBs showed a significantly greater ratio of 5-HT positive cells with an abundance of 5-HT; 4) NEBs in NMR expressed the proliferating cell nuclear antigen (PCNA) and the neurogenic gene (MASH1) indicating active proliferation and a state of persistent differentiation. Taken together our findings suggest that NEBs in lungs of NMR are in a hyperactive, functional and

  12. Non-Breeding Eusocial Mole-Rats Produce Viable Sperm--Spermiogram and Functional Testicular Morphology of Fukomys anselli.

    PubMed

    Garcia Montero, Angelica; Vole, Christiane; Burda, Hynek; Malkemper, Erich Pascal; Holtze, Susanne; Morhart, Michaela; Saragusty, Joseph; Hildebrandt, Thomas B; Begall, Sabine

    2016-01-01

    Ansell's mole-rats (Fukomys anselli) are subterranean rodents living in families composed of about 20 members with a single breeding pair and their non-breeding offspring. Most of them remain with their parents for their lifetime and help to maintain and defend the natal burrow system, forage, and care for younger siblings. Since incest avoidance is based on individual recognition (and not on social suppression) we expect that non-breeders produce viable sperm spontaneously. We compared the sperm of breeding and non-breeding males, obtained by electroejaculation and found no significant differences in sperm parameters between both groups. Here, we used electroejaculation to obtain semen for the first time in a subterranean mammal. Spermiogram analysis revealed no significant differences in sperm parameters between breeders and non-breeders. We found significantly larger testes (measured on autopsies and on living animals per ultrasonography) of breeders compared to non-breeders (with body mass having a significant effect). There were no marked histological differences between breeding and non-breeding males, and the relative area occupied by Leydig cells and seminiferous tubules on histological sections, respectively, was not significantly different between both groups. The seminiferous epithelium and to a lesser degree the interstitial testicular tissue are characterized by lesions (vacuolar degenerations), however, this feature does not hinder fertilization even in advanced stages of life. The continuous production of viable sperm also in sexually abstinent non-breeders might be best understood in light of the mating and social system of Fukomys anselli, and the potential to found a new family following an unpredictable and rare encounter with an unfamiliar female ("provoked or induced dispersal"). Apparently, the non-breeders do not reproduce because they do not copulate but not because they would be physiologically infertile. The significantly increased testes

  13. Impact of underlap and mole-fraction on RF performance of strained-Si/Si1-xGex/strained-Si DG MOSFETs

    NASA Astrophysics Data System (ADS)

    Dutta, Arka; Koley, Kalyan; Sarkar, Chandan K.

    2014-11-01

    In this paper, a systematic RF performance analysis of double-gate strained silicon (DGSS) nMOSFETs is presented. The analysis is focused upon impact of Germanium mole-fraction variation on RF performance of underlap engineered DGSS nMOSFET. The RF performance of the device is analysed as a function of intrinsic RF figure of merits (FOMs) including non-quasi static effects (NQS). The RF FOMs are represented by the intrinsic gate to source/drain capacitance (Cgs and Cgd) and resistance (Rgs and Rgd), the transport delay (τm), the intrinsic inductance (Lsd), the cut-off frequency (fT), and the maximum oscillation frequency (fMAX). The results of the study suggested a significant improvement in the device performance, up to 40% increase in Germanium mole fraction (χ).

  14. Une nouvelle espèce d'hyracoïde du genre Bunohyrax (Mammalia) de l'Éocène de Bir El Ater (Algérie).

    NASA Astrophysics Data System (ADS)

    Tabuce, Rodolphe; Coiffait, Brigitte; Coiffait, Philippe-Emmanuel; Mahboubi, Mohamed; Jaeger, Jean-Jacques

    2000-07-01

    A new species of Bunohyrax, B. matsumotoi n. sp. (Hyracoidea, Mammalia) from the Bir El Ater locality (Algeria) is described and compared with the two known species from the Oligocene of the Fayum (Egypt). This new hyracoid is documented by fragmentary remains, but the characters are significant enough to establish a new species, particularly because of its extremely small size. B. matsumotoi appears to be more primitive than the Egyptian Bunohyrax. The Algerian species, together with geological and palaeontological data, argues for a late Middle to Late Eocene age for the Bir El Ater site, rather than an Oligocene age, equivalent to the upper sequence of the Fayum, as suggested by Rasmussen et al. [17].

  15. The impact of gape on the performance of the skull in chisel-tooth digging and scratch digging mole-rats (Rodentia: Bathyergidae)

    PubMed Central

    McIntosh, Andrew F.

    2016-01-01

    The African mole-rats (Bathyergidae) are a family of rodents highly adapted for life underground. Previous research has shown that chisel-tooth digging mole-rats (which use their incisors to dig burrows) are clearly distinguishable from scratch diggers (which only use the forelimbs to tunnel) on the basis of morphology of the skull, and that the differences are linked to the production of high bite forces and wide gapes. We hypothesized that the skull of a chisel-tooth digging mole-rat would perform better at wider gapes than that of a scratch digging mole-rat during incisor biting. To test this hypothesis, we created finite-element models of the cranium of the scratch digging Bathyergus suillus and the chisel-tooth digging Fukomys mechowii, and loaded them to simulate incisor bites at different gapes. Muscle loads were scaled such that the ratio of force to surface area was the same in both models. We measured three performance variables: overall stress across the cranium, mechanical efficiency of biting and degree of deformation across the skull. The Fukomys model had a more efficient incisor bite at all gapes, despite having greater average stress across the skull. In addition, the Fukomys model deformed less at wider gapes, whereas the Bathyergus model deformed less at narrower gapes. These properties of the cranial morphology of Fukomys and Bathyergus are congruent with their respective chisel-tooth and scratch digging behaviours and, all other factors being equal, would enable the more efficient production of bite force at wider gapes in Fukomys. However, in vivo measurements of muscle forces and activation patterns are needed to fully understand the complex biomechanics of tooth digging. PMID:27853575

  16. Tunable diode laser absorption spectroscopy-based tomography system for on-line monitoring of two-dimensional distributions of temperature and H2O mole fraction

    NASA Astrophysics Data System (ADS)

    Xu, Lijun; Liu, Chang; Jing, Wenyang; Cao, Zhang; Xue, Xin; Lin, Yuzhen

    2016-01-01

    To monitor two-dimensional (2D) distributions of temperature and H2O mole fraction, an on-line tomography system based on tunable diode laser absorption spectroscopy (TDLAS) was developed. To the best of the authors' knowledge, this is the first report on a multi-view TDLAS-based system for simultaneous tomographic visualization of temperature and H2O mole fraction in real time. The system consists of two distributed feedback (DFB) laser diodes, a tomographic sensor, electronic circuits, and a computer. The central frequencies of the two DFB laser diodes are at 7444.36 cm-1 (1343.3 nm) and 7185.6 cm-1 (1391.67 nm), respectively. The tomographic sensor is used to generate fan-beam illumination from five views and to produce 60 ray measurements. The electronic circuits not only provide stable temperature and precise current controlling signals for the laser diodes but also can accurately sample the transmitted laser intensities and extract integrated absorbances in real time. Finally, the integrated absorbances are transferred to the computer, in which the 2D distributions of temperature and H2O mole fraction are reconstructed by using a modified Landweber algorithm. In the experiments, the TDLAS-based tomography system was validated by using asymmetric premixed flames with fixed and time-varying equivalent ratios, respectively. The results demonstrate that the system is able to reconstruct the profiles of the 2D distributions of temperature and H2O mole fraction of the flame and effectively capture the dynamics of the combustion process, which exhibits good potential for flame monitoring and on-line combustion diagnosis.

  17. The impact of gape on the performance of the skull in chisel-tooth digging and scratch digging mole-rats (Rodentia: Bathyergidae)

    NASA Astrophysics Data System (ADS)

    McIntosh, Andrew F.; Cox, Philip G.

    2016-10-01

    The African mole-rats (Bathyergidae) are a family of rodents highly adapted for life underground. Previous research has shown that chisel-tooth digging mole-rats (which use their incisors to dig burrows) are clearly distinguishable from scratch diggers (which only use the forelimbs to tunnel) on the basis of morphology of the skull, and that the differences are linked to the production of high bite forces and wide gapes. We hypothesized that the skull of a chisel-tooth digging mole-rat would perform better at wider gapes than that of a scratch digging mole-rat during incisor biting. To test this hypothesis, we created finite-element models of the cranium of the scratch digging Bathyergus suillus and the chisel-tooth digging Fukomys mechowii, and loaded them to simulate incisor bites at different gapes. Muscle loads were scaled such that the ratio of force to surface area was the same in both models. We measured three performance variables: overall stress across the cranium, mechanical efficiency of biting and degree of deformation across the skull. The Fukomys model had a more efficient incisor bite at all gapes, despite having greater average stress across the skull. In addition, the Fukomys model deformed less at wider gapes, whereas the Bathyergus model deformed less at narrower gapes. These properties of the cranial morphology of Fukomys and Bathyergus are congruent with their respective chisel-tooth and scratch digging behaviours and, all other factors being equal, would enable the more efficient production of bite force at wider gapes in Fukomys. However, in vivo measurements of muscle forces and activation patterns are needed to fully understand the complex biomechanics of tooth digging.

  18. Measurement of InAsBi mole fraction and InBi lattice constant using Rutherford backscattering spectrometry and X-ray diffraction

    NASA Astrophysics Data System (ADS)

    Shalindar, A. J.; Webster, P. T.; Wilkens, B. J.; Alford, T. L.; Johnson, S. R.

    2016-10-01

    Several 1 μm thick, nearly lattice-matched InAsBi layers grown on GaSb are examined using Rutherford backscattering spectrometry and X-ray diffraction. Random Rutherford backscattering measurements indicate that the average Bi mole fraction ranges from 0.0503 to 0.0645 for the sample set, and ion-channeling measurements indicate that the Bi atoms are substitutional. The X-ray diffraction measurements show a diffraction sideband near the main (004) diffraction peak, indicating that the Bi mole fraction is not laterally uniform in the layer. The average out-of-plane tetragonal distortion is determined by modeling the main and sideband diffraction peaks, from which the average unstrained lattice constant of each sample is determined. By comparing the Bi mole fraction measured by random Rutherford backscattering with the InAsBi lattice constant for the sample set, the lattice constant of zinc blende InBi is determined to be 6.6107 Å.

  19. Effect of the growth temperature and the AlN mole fraction on In incorporation and properties of quaternary III-nitride layers grown by molecular beam epitaxy

    SciTech Connect

    Fernandez-Garrido, S.; Pereiro, J.; Munoz, E.; Calleja, E.; Gago, R.; Bertram, F.; Christen, J.; Luna, E.; Trampert, A.

    2008-10-15

    Indium incorporation into wurtzite (0001)-oriented In{sub x}Al{sub y}Ga{sub 1-x-y}N layers grown by plasma-assisted molecular beam epitaxy was studied as a function of the growth temperature (565-635 deg. C) and the AlN mole fraction (0.01mole fractions. High resolution x-ray diffraction and transmission electron microscopy (TEM) measurements did not show evidence of phase separation. The mosaicity of the quaternary layers was found to be mainly determined by the growth temperature and independent on alloy composition within the range studied. However, depending on the AlN mole fraction, nanometer-sized composition fluctuations were detected by TEM. Photoluminescence spectra showed a single broad emission at room temperature, with energy and bandwidth S- and W-shaped temperature dependences typical of exciton localization by alloy inhomogeneities. Cathodoluminescence measurements demonstrated that the alloy inhomogeneities, responsible of exciton localization, occur on a lateral length scale below 150 nm, which is corroborated by TEM.

  20. Effect of SiO2/Na2O mole ratio on the properties of foam geopolymers fabricated from circulating fluidized bed fly ash

    NASA Astrophysics Data System (ADS)

    Liu, Ze; Shao, Ning-ning; Huang, Tian-yong; Qin, Jun-feng; Wang, Dong-min; Yang, Yu

    2014-06-01

    Geopolymers are three-dimensional aluminosilicates formed in a short time at low temperature by geopolymerization. In this paper, alkali-activated foam geopolymers were fabricated from circulating fluidized bed fly ash (CFA), and the effect of SiO2/Na2O mole ratio (0.91-1.68) on their properties was studied. Geopolymerization products were characterized by mechanical testing, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The results show that SiO2/Na2O mole ratio plays an important role in the mechanical and morphological characteristics of geopolymers. Foam samples prepared in 28 d with a SiO2/Na2O mole ratio of 1.42 exhibit the greatest compressive strength of 2.52 MPa. Morphological analysis reveals that these foam geopolymers appear the relatively optimized pore structure and distribution, which are beneficial to the structure stability. Moreover, a combination of the Si/Al atomic ratio ranging between 1.47 and 1.94 with the Na/Al atomic ratio of about 1 produces the samples with high strength.

  1. The effect of diet on microfaunal population and function in the caecum of a subterranean naked mole-rat, Heterocephalus glaber.

    PubMed

    Buffenstein, R; Yahav, S

    1991-03-01

    The effect of dietary fibre and starch content on digestibility, microfaunal population and caecal function was investigated in a subterranean mole-rat, Heterocephalus glaber (Rodentia). Mole-rats were fed on a diet of either sweet potato (neutral-detergent fibre (NDF) 65 g/kg dry matter (DM), starch 638 g/kg DM) or carrot (NDF 157 g/kg DM, starch 258.7 g/kg DM) for 4 weeks. Daily intake and faecal output were monitored. Thereafter caecal microfaunal population, density and function were assessed using light and scanning electron microscopy and by measuring both gas and short chain fatty acid (SCFA) production. A 2.4-fold increase in fibre and 2.5-fold decrease in starch content resulted in a decrease in caecal DM content (390 g/kg). A concomitant dramatic decline (by 93%) in ciliate protozoa with a corresponding 2-fold increase in bacteria also accompanied this change in diet. Fermentative efficiency as indicated by gas production was 2.6 times greater on a carrot diet than on sweet potato. Microbial fermentation resulted in higher SCFA concentrations on the carrot diet, with a 42% reduction in SCFA concentration on the sweet potato diet. Here, SCFA contributed 5.1% of daily energy expenditure and this increased 5.0-fold on the carrot diet. Caecal micro-organism function, therefore, played an important role in the nutritional physiology of these naked mole-rats, and enabled maximum utilization of the food substrate.

  2. Existence of serotonin and neuropeptides-immunoreactive endocrine cells in the small and large intestines of the mole-rats (Spalax leucodon).

    PubMed

    Yaman, M; Bayrakdar, A; Tarakçı, B G

    2012-08-01

    The present study was conducted to clarify the regional distribution and relative frequency of endocrine cells secreting serotonin, substance P (SP), cholecystokinin-8 (CCK-8), vasoactive intestinal polypeptide (VIP) and neurotensin in the small and large intestine of the mole-rats (Spalax leucodon), by specific immunohistochemical methods. In the small and large intestine of mole-rats (Spalax leucodon), serotonin, SP and VIP were identified with various frequencies, but CCK-8 and neurotensin were not observed. Most of the IR cells in the small and large intestine were located in the intestinal crypt and epithelium however, they were more frequency in the intestinal crypt. Serotonin-IR cells were detected throughout the whole intestinal tract, predominantly in the duodenum and colon. SP-IR cells were demonstrated throughout the whole intestinal tract except for the ileum and rectum with highest frequencies in the cecum. VIP-IR cells were found in all parts of the small intestine except for the large intestine. In conclusion, the general distribution patterns and relative frequency of intestinal endocrine cells of the mole-rats (Spalax leucodon) was similar to those of some rodent species. However, some species-dependent unique distributions and frequencies characteristics of endocrine cells were also observed in the present study.

  3. The effects of oxotremorine, epibatidine, atropine, mecamylamine and naloxone in the tail-flick, hot-plate, and formalin tests in the naked mole-rat (Heterocephalus glaber).

    PubMed

    Dulu, Thomas D; Kanui, Titus I; Towett, Philemon K; Maloiy, Geoffrey M; Abelson, Klas S P

    2014-01-01

    The naked mole-rat (Heterocephalus glaber) is a promising animal model for the study of pain mechanisms, therefore a thorough characterization of this species is essential. The aim of the present study was to establish the naked mole-rat as a model for studying the cholinergic receptor system in antinociception by investigating the involvement of muscarinic, nicotinic and opioid receptors in nociceptive tests in this species. The effects of systemic administration of the muscarinic receptor agonist oxotremorine and the nicotinic receptor agonist epibatidine were investigated in the tail-flick, the hot-plate, and the formalin tests. The effects of co-administration of the muscarinic receptor antagonist atropine, the nicotinic receptor antagonist mecamylamine, and the opioid receptor antagonist naloxone were also investigated. Oxotremorine and epibatidine induced a significant, dose-dependent antinociceptive effect in the tail-flick, hot-plate, and formalin tests, respectively. The effects of oxotremorine and epibatidine were blocked by atropine and mecamylamine, respectively. In all three nociceptive tests, naloxone in combination with oxotremorine or epibatidine enhanced the antinociceptive effects of the drugs. The present study demonstrated that stimulation of muscarinic and nicotinic receptors produces antinociceptive effects in the naked-mole rat. The reversal effect of atropine and mecamylamine suggests that this effect is mediated by cholinergic receptors. As naloxone increases the antinociceptive effects of cholinergic agonists, it is suggested that the cholinergic antinociception acts via a gateway facilitated by opioid receptor blockage; however, the precise interaction between these receptor systems needs further investigation.

  4. Study of Age-Dependent Structural and Functional Changes of Mitochondria in Skeletal Muscles and Heart of Naked Mole Rats (Heterocephalus glaber).

    PubMed

    Holtze, S; Eldarov, C M; Vays, V B; Vangeli, I M; Vysokikh, M Yu; Bakeeva, L E; Skulachev, V P; Hildebrandt, T B

    2016-12-01

    Morphometric analysis of mitochondria in skeletal muscles and heart of 6- and 60-month-old naked mole rats (Heterocephalus glaber) revealed a significant age-dependent increase in the total area of mitochondrial cross-sections in studied muscle fibers. For 6- and 60-month-old animals, these values were 4.8 ± 0.4 and 12.7 ± 1.8%, respectively. This effect is mainly based on an increase in the number of mitochondria. In 6-month-old naked mole rats, there were 0.23 ± 0.02 mitochondrial cross-sections per µm(2) of muscle fiber, while in 60-month-old animals this value was 0.47 ± 0.03. The average area of a single mitochondrial cross-section also increased with age in skeletal muscles - from 0.21 ± 0.01 to 0.29 ± 0.03 µm(2). Thus, naked mole rats show a drastic enlargement of the mitochondrial apparatus in skeletal muscles with age due to an increase in the number of mitochondria and their size. They possess a neotenic type of chondriome accompanied by specific features of mitochondrial functioning in the state of oxidative phosphorylation and a significant decrease in the level of matrix adenine nucleotides.

  5. Low sulfide levels and a high degree of cystathionine β-synthase (CBS) activation by S-adenosylmethionine (SAM) in the long-lived naked mole-rat

    PubMed Central

    Dziegelewska, Maja; Holtze, Susanne; Vole, Christiane; Wachter, Ulrich; Menzel, Uwe; Morhart, Michaela; Groth, Marco; Szafranski, Karol; Sahm, Arne; Sponholz, Christoph; Dammann, Philip; Huse, Klaus; Hildebrandt, Thomas; Platzer, Matthias

    2016-01-01

    Hydrogen sulfide (H2S) is a gaseous signalling molecule involved in many physiological and pathological processes. There is increasing evidence that H2S is implicated in aging and lifespan control in the diet-induced longevity models. However, blood sulfide concentration of naturally long-lived species is not known. Here we measured blood sulfide in the long-lived naked mole-rat and five other mammalian species considerably differing in lifespan and found a negative correlation between blood sulfide and maximum longevity residual. In addition, we show that the naked mole-rat cystathionine β-synthase (CBS), an enzyme whose activity in the liver significantly contributes to systemic sulfide levels, has lower activity in the liver and is activated to a higher degree by S-adenosylmethionine compared to other species. These results add complexity to the understanding of the role of H2S in aging and call for detailed research on naked mole-rat transsulfuration. PMID:26803480

  6. Spatial and Temporal Variability of Methane Mole Fractions and Exchanges in and Between Soil, Snow, and the Atmosphere in a Tundra System in Northern Alaska

    NASA Astrophysics Data System (ADS)

    Agnan, Y.; Obrist, D.; Edwards, G. C.; Moore, C.; Hedge, C.; Helmig, D.; Paxton, D.; Jacques, H.

    2015-12-01

    An important global source of atmospheric methane (CH4) is production in tundra soils (an important global source). To place constraints on the potential role that tundra soils play in global CH4 cycling, we have been continuously measuring mole the air space in soils, snow, and the atmosphere as gradient-based surface-atmosphere fluxes for arctic tundra at Toolik Field Station (68° 38' N) starting in October 2014. We have found that atmospheric CH4 mole fractions were, on average, relatively constant during the first 9 months of sampling (averaging 1.93 µmol mol-1), with pronounced diel patterns starting in May and nighttime exceeding daytime mole fractions. However, gradients measured within the soil profile showed high variability in air withdrawn from different locations of these tundra soils (Typic Aquiturbels), with one soil profile indicating a CH4 sink during fall until January; mole fractions were similar to the atmospheric measurements during winter indicating no source or sink (average 1.89 µmol mol-1). A second soil profile 5 m away showed production of CH4 (average 2.48 µmol mol-1, two-times higher than atmospheric levels), even during mid-winter when soil temperatures were below -10 °C. Measurements of CH4 in interstitial snowpack air also exhibited a similar combination of sources and sinks. We used micrometeorological gradient surface flux measurements to confirm that the area was a net source of CH4 in fall, winter, and spring, with emissions averaging 26.6, 25.2, and 16.8 mg m-2 d-1, respectively. In the summer months, we saw strong diel flux patterns with deposition during day and emission at night, corresponding with observed diel variability in CH4 snowpack mole fractions. Our results indicated a high variability of tundra landscape CH4 fluxes, which locally shift from sources to sinks with high temporal variability. CH4 oxidation by methanotrophic bacteria probably occurs in tundra soils, confirming observations in one soil, snowpack, and

  7. Insights Into the Recent Rise in Atmospheric Methane Inferred from Observed Mole Fractions and Stable Carbon Isotopes

    NASA Astrophysics Data System (ADS)

    White, J. W. C.; Michel, S. E.; Tans, P. P.; Vaughn, B. H.; Dlugokencky, E. J.; Sherwood, O.; Miller, J. B.; Masarie, K. A.

    2015-12-01

    Methane is a troublesome greenhouse gas. It has multiple natural and anthropogenic sources, including microbial production in low oxygen environments, fossil sources related to coal and natural gas production, and biomass burning, making source attribution difficult. Atmospheric methane concentration rose rapidly in the industrial period, increasing by 250%, only to stall out in the first decade this century, and then rising again after 2007. Its emission is strongly related to variables that are hard to predict, such as precipitation rates, biomass burning, and natural gas use, so future projections remain murky. And unlike CO2, which is strongly tied to energy use, anthropogenic impacts on methane are strongly tied to food production. Finally, methane is expected to be released from a thawing Arctic in large, but largely unknown quantities. Understanding methane as a greenhouse gas is imperative if anthropogenic impacts on the climate system are to be managed in the future. This talk addresses what we can say about the recent rise in methane using mole fractions and 13C data from the existing NOAA Cooperative Global Air Sampling Network. The approach is strongly data based, and while we will present model results, the data itself are clear on several points. While attention is increasingly focused on the Arctic, the north-south gradient of CH4 concentration does not support significant changes to Boreal and Arctic emissions. This finding raises the question of how methane will behave in a warmer, wetter world. We use a simple, three end-member model, run in both forward and inverse modes, to look more deeply into the sources of the recent increase. Evidence exists for recent increases in fossil sources, in line with methane production as a fuel source, although the contribution is small. Better data are needed to constrain the 13C of sources, including the fossil sources, a problem we are working on. Importantly, while the current monitoring network is adequate

  8. Absence of Maternal Methylation in Biparental Hydatidiform Moles from Women with NLRP7 Maternal-Effect Mutations Reveals Widespread Placenta-Specific Imprinting

    PubMed Central

    Sanchez-Delgado, Marta; Martin-Trujillo, Alejandro; Tayama, Chiharu; Vidal, Enrique; Esteller, Manel; Iglesias-Platas, Isabel; Deo, Nandita; Barney, Olivia; Maclean, Ken; Hata, Kenichiro; Nakabayashi, Kazuhiko; Fisher, Rosemary; Monk, David

    2015-01-01

    Familial recurrent hydatidiform mole (RHM) is a maternal-effect autosomal recessive disorder usually associated with mutations of the NLRP7 gene. It is characterized by HM with excessive trophoblastic proliferation, which mimics the appearance of androgenetic molar conceptuses despite their diploid biparental constitution. It has been proposed that the phenotypes of both types of mole are associated with aberrant genomic imprinting. However no systematic analyses for imprinting defects have been reported. Here, we present the genome-wide methylation profiles of both spontaneous androgenetic and biparental NLRP7 defective molar tissues. We observe total paternalization of all ubiquitous and placenta-specific differentially methylated regions (DMRs) in four androgenetic moles; namely gain of methylation at paternally methylated loci and absence of methylation at maternally methylated regions. The methylation defects observed in five RHM biopsies from NLRP7 defective patients are restricted to lack-of-methylation at maternal DMRs. Surprisingly RHMs from two sisters with the same missense mutations, as well as consecutive RHMs from one affected female show subtle allelic methylation differences, suggesting inter-RHM variation. These epigenotypes are consistent with NLRP7 being a maternal-effect gene and involved in imprint acquisition in the oocyte. In addition, bioinformatic screening of the resulting methylation datasets identified over sixty loci with methylation profiles consistent with imprinting in the placenta, of which we confirm 22 as novel maternally methylated loci. These observations strongly suggest that the molar phenotypes are due to defective placenta-specific imprinting and over-expression of paternally expressed transcripts, highlighting that maternal-effect mutations of NLRP7 are associated with the most severe form of multi-locus imprinting defects in humans. PMID:26544189

  9. Structural Changes and Lack of HCN1 Channels in the Binaural Auditory Brainstem of the Naked Mole-Rat (Heterocephalus glaber).

    PubMed

    Gessele, Nikodemus; Garcia-Pino, Elisabet; Omerbašić, Damir; Park, Thomas J; Koch, Ursula

    2016-01-01

    Naked mole-rats (Heterocephalus glaber) live in large eu-social, underground colonies in narrow burrows and are exposed to a large repertoire of communication signals but negligible binaural sound localization cues, such as interaural time and intensity differences. We therefore asked whether monaural and binaural auditory brainstem nuclei in the naked mole-rat are differentially adjusted to this acoustic environment. Using antibody stainings against excitatory and inhibitory presynaptic structures, namely the vesicular glutamate transporter VGluT1 and the glycine transporter GlyT2 we identified all major auditory brainstem nuclei except the superior paraolivary nucleus in these animals. Naked mole-rats possess a well structured medial superior olive, with a similar synaptic arrangement to interaural-time-difference encoding animals. The neighboring lateral superior olive, which analyzes interaural intensity differences, is large and elongated, whereas the medial nucleus of the trapezoid body, which provides the contralateral inhibitory input to these binaural nuclei, is reduced in size. In contrast, the cochlear nucleus, the nuclei of the lateral lemniscus and the inferior colliculus are not considerably different when compared to other rodent species. Most interestingly, binaural auditory brainstem nuclei lack the membrane-bound hyperpolarization-activated channel HCN1, a voltage-gated ion channel that greatly contributes to the fast integration times in binaural nuclei of the superior olivary complex in other species. This suggests substantially lengthened membrane time constants and thus prolonged temporal integration of inputs in binaural auditory brainstem neurons and might be linked to the severely degenerated sound localization abilities in these animals.

  10. Dependence of source gas mole ratio on crystalline quality of ZnSe layers grown on (100) ZnSe substrates by atmospheric pressure metalorganic vapor phase epitaxy

    NASA Astrophysics Data System (ADS)

    Yodo, T.; Koyama, T.; Yamashita, K.

    1988-10-01

    Single crystalline layers of undoped ZnSe have been grown on (100) ZnSe substrates at 250°C by atmospheric pressure metalorganic vapor phase epitaxy (MOVPE) using dimethylzinc (DMZ) and hydrogen selenide (H 2Se). The surface morphologies, observed by a Nomarski phase contrast interference microscope, depend on the growth conditions, particularly the source gas mole ratio η M ( ηM=[Se]/[Zn]). The surface morphologies of homoepilayers grown with η M of more than 15 are very rough like polycrystals. However, these layers have the best crystalline quality as determined by a double crystal X-ray diffraction spectrometer (the full width at half maximum (FWHM) of (400) diffraction is 33 arc sec). The surface morphologies of layers grown at values of η M between 3 and 15 are excellent as well as those of heteroepilayers (GaAs substrates are used). On the other hand, the crystalline quality becomes worse by reducing η M. The photoluminescence (PL) spectra at 4.2 K exhibit strong and well-resolved band-edge emissions from the donor bound exciton (hereafter called I x) and the free exciton (hereafter called E x) only for the low mole ratio (η M<10). The FWHM of I x is 0.8 meV which is sharper than that of heteroepilayers. However, the intensity of emissions from deep levels (deep emissions) of homoepilayers measured at 77 K is several times stronger than that of heteroepilayers. In the region of high mole ratio (η M>10), the PL spectra at 4.2 K show two broad lines: I x and the unknown I v (probably donor bound exciton). And the intensity of I x reduces two orders by decreasing the mole ratio from 20 to 3. This indicates that the concentration of donor decreases for the Se-rich condition. From the investigation of PL measurements, the origin of deep emissions is considered to be caused by complexes of Zn vacancies and impurities from the source gases. The dependences of η M on the quality of homoepilayers observed in this work are quite different from those in

  11. Chromosomal evolution of Arvicolinae (Cricetidae, Rodentia). II. The genome homology of two mole voles (genus Ellobius), the field vole and golden hamster revealed by comparative chromosome painting.

    PubMed

    Romanenko, Svetlana A; Sitnikova, Natalia A; Serdukova, Natalya A; Perelman, Polina L; Rubtsova, Nadezhda V; Bakloushinskaya, Irina Yu; Lyapunova, Elena A; Just, Walter; Ferguson-Smith, Malcolm A; Yang, Fengtang; Graphodatsky, Alexander S

    2007-01-01

    Using cross-species chromosome painting, we have carried out a comprehensive comparison of the karyotypes of two Ellobius species with unusual sex determination systems: the Transcaucasian mole vole, Ellobius lutescens (2n = 17, X in both sexes), and the northern mole vole, Ellobius talpinus (2n = 54, XX in both sexes). Both Ellobius species have highly rearranged karyotypes. The chromosomal paints from the field vole (Microtus agrestis) detected, in total, 34 and 32 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. No difference in hybridization pattern of the X paint (as well as Y paint) probes on male and female chromosomes was discovered. The set of golden hamster (Mesocricetus auratus) chromosomal painting probes revealed 44 and 43 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. A comparative chromosome map was established based on the results of cross-species chromosome painting and a hypothetical ancestral Ellobius karyotype was reconstructed. A considerable number of rearrangements were detected; 31 and 7 fusion/fission rearrangements differentiated the karyotypes of E. lutescens and E. talpinus from the ancestral Ellobius karyotype. It seems that inversions have played a minor role in the genome evolution of these Ellobius species.

  12. Comparative Morphology of the Papillae Linguales and their Connective Tissue Cores in the Tongue of the Greater Japanese Shrew-mole, Urotrichus talpoides

    PubMed Central

    Yoshimura, K; Shindo, J; Kageyama, I

    2013-01-01

    The external morphology of the papillae linguales (papillae filiformes, papillae fungiformes and papillae vallatae) and their connective tissue cores (CTCs) of the greater Japanese shrew-mole (Urotrichus talpoides) were analysed by optical and scanning electron microscopy. Papillae filiformes were distributed over the dorsal surface of the apex linguae, and on the rostral and caudal regions of the corpus linguae but were less numerous in the mid-region. They were absent from the radix linguae. A pair of oval papillae vallatae was situated at the border between the corpus linguae and the radix linguae. Papillae foliatae were absent. The epithelial surface of each papilla filiformis consisted of a circular concavity, a ring-like wall and either a single thumb-like process or 2–3 slender pointed processes, depending on their location. The morphology of the CTCs of the papillae filiformes also varied regionally. The papillae linguales of the Japanese shrew-mole were morphologically similar to those of other Talpidae and Soricidae, including the common shrew, particularly with respect to the papillae filiformes in the mid- and caudal regions of the corpus linguae. PMID:22571539

  13. Large Amplitude Spatial and Temporal Gradients in Atmospheric Boundary Layer CO2 Mole Fractions Detected With a Tower-Based Network in the U.S. Upper Midwest

    SciTech Connect

    Miles, Natasha; Richardson, S. J.; Davis, Kenneth J.; Lauvaux, Thomas; Andrews, A.; West, Tristram O.; Bandaru, Varaprasad; Crosson, Eric R.

    2012-02-21

    This study presents observations of atmospheric CO{sub 2} mole fraction from a nine-tower, regional network deployed during the North American Carbon Program's Mid-Continent Intensive during 2007-2009. Within this network in a largely agricultural area, mean atmospheric CO{sub 2} gradients were strongly correlated with both ground-based inventory data and estimates from satellite remote sensing. The average seasonal drawdown for corn-dominated sites (35 ppm) is significantly larger than has been observed at other continental boundary layer sites. Observed growing-season median CO{sub 2} gradients are strongly dependent on local flux. The gradients between cross-vegetation site-pairs, for example, average 2.0 ppm/100 km, four times larger than the similar-vegetation site-pair average. Daily-timescale gradients are as large as 5.5 ppm/100 km, but dominated by advection rather than local flux. Flooding in 2008 led to a region-wide 23 week delay in growing-season minima. The observations show that regional-scale CO{sub 2} mole fraction networks yield large, coherent signals governed largely by regional sources and sinks of CO{sub 2}.

  14. The assumption of the conservation of mass and its implications for present and future definitions of the kilogram and the mole

    NASA Astrophysics Data System (ADS)

    Davis, Richard S.; Milton, Martin J. T.

    2014-06-01

    In the International System of Units (SI), the definition of the mole sets the value of the molar mass of carbon-12, M(12C), exactly equal to 0.012 kg mol-1 whereas the Avogadro constant, NA, which is the molar number of entities, is measured experimentally. In the proposed ‘new SI’ the principles underlying these relationships will be reversed. However, because the kilogram will also be redefined, the relative uncertainty of the molar mass of carbon-12 will be about 50 times smaller than the present relative uncertainty of NA. Critics contend that the mole should not be redefined because a finite uncertainty of M(12C) would be inconvenient for chemists. This criticism tacitly assumes that mass is conserved in chemical reactions and hence that the equivalent masses of chemical bond energies are negligible. Taking as an example the x-ray crystal density experiment to measure NA by determining the number of atoms in a silicon crystal, we estimate that the mass equivalent of chemical bonds in the crystal is approximately 0.18 µg for a 1 kg crystal. By coincidence, this is approximately equal to the relative uncertainty with which M(12C) will be known in the new SI. Various implications of this are discussed.

  15. Complete hydatidiform mole and a coexistent fetus following ovulation induction in a patient with Sheehan's syndrome: a first case report and review of literature.

    PubMed

    Huang, Xuekun; Liang, Jingyao; Huang, Yonghan; Huang, Juanhua

    2014-05-01

    Pregnancy in Sheehan's syndrome (SS) is extremely rare. We present the first reported case of twin pregnancy with complete hydatiform mole (CHM) and a coexistent fetus (CHCF) in a patient with SS. A 29-year-old Chinese patient with SS became pregnant following one cycle of ovulation induction with human menopausal gonadotropin after secondary infertility. A normal live fetus and a low echogenic mass suspected hydatidiform mole (HM) were detected by ultrasound examinations at gestational week 8. The couple highly desired to continue the pregnancy because it is very hard to get pregnant for the patients with SS. However, the pregnancy was terminated for the size of the HM component increased rapidly at gestational week 15. Histological examinations confirmed CHCF. Genetic studies showed that the CHM genome was derived from paternal diploidy, and the normal fetus was from biparental genomes. Furthermore, a literature review on these topics is included. This case highlighted that even in a patient with SS, twin pregnancy with CHCF can still occur after ovulation induction.

  16. Analysis of CO2 mole fraction data: first evidence of large-scale changes in CO2 uptake at high northern latitudes

    NASA Astrophysics Data System (ADS)

    Barlow, J. M.; Palmer, P. I.; Bruhwiler, L. M.; Tans, P.

    2015-03-01

    Atmospheric variations of carbon dioxide (CO2) mole fraction reflect changes in atmospheric transport and regional patterns of surface emission and uptake. We report new estimates for changes in the phase and amplitude of observed high northern latitude CO2 seasonal variations, indicative of biospheric changes, by spectrally decomposing multi-decadal records of surface CO2 mole fraction using a wavelet transform to isolate the changes in the observed seasonal cycle. We also perform similar analysis of the first time derivative of CO2 mole fraction, ΔtCO2, that is a crude proxy for changes in CO2 flux. Using numerical experiments, we quantify the aliasing error associated with independently identifying trends in phase and peak uptake and release to be 10-25%, with the smallest biases in phase associated with the analysis of ΔtCO2. We report our analysis from Barrow, Alaska (BRW) during 1973-2013, which is representative of the broader Arctic region. We determine an amplitude trend of 0.09 ± 0.02 ppm yr-1, which is consistent with previous work. Using ΔtCO2 we determine estimates for the timing of the onset of net uptake and release of CO2 of -0.14 ± 0.14 and -0.25 ± 0.08 days yr-1, respectively, and a corresponding uptake period of -0.11 ± 0.16 days yr-1, which are significantly different to previously reported estimates. We find that the wavelet transform method has significant skill in characterizing changes in the peak uptake and release. We find a trend of 0.65 ± 0.34% (p< 0.01) and 0.42 ± 0.34% (p<0.05) for rates of peak uptake and release, respectively. Our analysis does not provide direct evidence about the balance between uptake and release of carbon, but changes in the peak uptake and release together with an invariant growing period length provides indirect evidence that high northern latitude ecosystems are progressively taking up more carbon.

  17. Analysis of CO2 mole fraction data: first evidence of large-scale changes in CO2 uptake at high northern latitudes

    NASA Astrophysics Data System (ADS)

    Barlow, J. M.; Palmer, P. I.; Bruhwiler, L. M.; Tans, P.

    2015-12-01

    Atmospheric variations of carbon dioxide (CO2) mole fraction reflect changes in atmospheric transport and regional patterns of surface emission and uptake. Here we present a study of changes in the observed high northern latitude CO2 seasonal cycle. We report new estimates for changes in the phase and amplitude of the seasonal variations, indicative of biospheric changes, by spectrally decomposing multi-decadal records of surface CO2 mole fraction using a wavelet transform to isolate the changes in the observed seasonal cycle. We also perform similar analysis of the first derivative of CO2 mole fraction, ΔtCO2, that is a crude proxy for changes in CO2 flux. Using numerical experiments, we quantify the aliasing error associated with independently identifying trends in phase and peak uptake and release to be 10-25 %, with the smallest biases in phase associated with the analysis of ΔtCO2. We report our analysis from Barrow, Alaska (BRW), during 1973-2013, which is representative of the broader Arctic region. We determine an amplitude trend of 0.09 ± 0.02 ppm yr-1, which is consistent with previous work. Using ΔtCO2 we determine estimates for the timing of the onset of net uptake and release of CO2 of -0.14 ± 0.14 and -0.25 ± 0.08 days yr-1 respectively and a corresponding net uptake period of -0.11 ± 0.16 days yr-1, which are significantly different to previously reported estimates. We find that the wavelet transform method has significant skill in characterizing changes in the peak uptake and release. We find a trend of 0.65 ± 0.34 % yr-1 (p < 0.01) and 0.42 ± 0.34 % yr-1 (p < 0.05) for rates of peak uptake and release respectively. Our analysis does not provide direct evidence about the balance between uptake and release of carbon when integrated throughout the year, but the increase in the seasonal amplitude of CO2 together with an invariant net carbon uptake period provides evidence that high northern latitude ecosystems are progressively taking up more

  18. Grossesse gémellaire associant une grossesse molaire et un fœtus vivant avec évolution vers mole invasive: à propos de deux cas

    PubMed Central

    Boubess, Ikram; Filali, Adib; Benbrahim, Fayssal; Ouassour, Salma; Tazi, Mokha; Alami, Mohammad Hassan

    2015-01-01

    La grossesse gémellaire associant une môle complète et une grossesse singleton normale possédant son propre trophoblaste sain est une entité rare. La majorité des études montre que le pronostic d'une telle association comprend un risque un peu plus accru d’évolution vers une tumeur trophoblastique gestationnelle. Nous rapportons deux cas de patientes qui ont consulté pour des métrorragies du premier trimestre et dont l’échographie a objectivé une grossesse gémellaire associant une grossesse molaire et une grossesse évolutive singleton et dont l’évolution était marqué par une mole invasive. PMID:26664525

  19. On the reliable analysis of indium mole fraction within In{sub x}Ga{sub 1−x}N quantum wells using atom probe tomography

    SciTech Connect

    Riley, James R.; Lauhon, Lincoln J.; Detchprohm, Theeradetch; Wetzel, Christian

    2014-04-14

    Surface crystallography and polarity are shown to influence the detection probability of In, Ga, and N ions during atom probe tomography analysis of In{sub x}Ga{sub 1−x}N m-plane, c-plane, and (202{sup ¯}1{sup ¯}) quantum wells. A N deficit is observed in regions of the reconstruction generated from Ga-polar surfaces, and the probability of detecting group-III atoms is lower in In{sub x}Ga{sub 1−x}N quantum wells than in GaN barrier layers. Despite these artifacts, the detected In mole fraction is consistent throughout a given quantum well regardless of the crystal orientation of the quantum well or the evaporation surface from which the reconstruction was generated.

  20. Reaching Out to Send a Message: Proteins Associated with Neurite Outgrowth and Neurotransmission are Altered with Age in the Long-Lived Naked Mole-Rat.

    PubMed

    Triplett, Judy C; Swomley, Aaron M; Kirk, Jessime; Grimes, Kelly M; Lewis, Kaitilyn N; Orr, Miranda E; Rodriguez, Karl A; Cai, Jian; Klein, Jon B; Buffenstein, Rochelle; Butterfield, D Allan

    2016-07-01

    Aging is the greatest risk factor for developing neurodegenerative diseases, which are associated with diminished neurotransmission as well as neuronal structure and function. However, several traits seemingly evolved to avert or delay age-related deterioration in the brain of the longest-lived rodent, the naked mole-rat (NMR). The NMR remarkably also exhibits negligible senescence, maintaining an extended healthspan for ~75 % of its life span. Using a proteomic approach, statistically significant changes with age in expression and/or phosphorylation levels of proteins associated with neurite outgrowth and neurotransmission were identified in the brain of the NMR and include: cofilin-1; collapsin response mediator protein 2; actin depolymerizing factor; spectrin alpha chain; septin-7; syntaxin-binding protein 1; synapsin-2 isoform IIB; and dynamin 1. We hypothesize that such changes may contribute to the extended lifespan and healthspan of the NMR.

  1. E-Cadherin, CD44v6, and Insulin-Like Growth Factor-II mRNA-Binding Protein 3 Expressions in Different Stages of Hydatidiform Moles.

    PubMed

    Wang, Jiajun; Zhao, Min; Xiao, Jianping; Wu, Man; Song, Yaohua; Yin, Yongxiang

    2016-09-01

    E-cadherin, CD44v6, and IMP3 expression in partial, complete, and invasive hydatidiform moles (HMs) was evaluated. High E-cadherin expression with low CD44v6 expression was observed in partial, complete, and invasive HMs, as well as in normal placental tissues; and there was no significant difference in E-cadherin and CD44v6 expression among the four groups. However, IMP3 expression was gradually decreased in the order of normal placental tissues, partial HMs, complete HMs, and invasive HMs; wherein, invasive HMs had the lowest level. Low IMP3 expression may serve as a prognostic biomarker for HMs, and IMP3 may play a certain role in HMs progression.

  2. Assessing Animal Welfare Impacts in the Management of European Rabbits (Oryctolagus cuniculus), European Moles (Talpa europaea) and Carrion Crows (Corvus corone)

    PubMed Central

    Baker, Sandra E.; Sharp, Trudy M.; Macdonald, David W.

    2016-01-01

    Human-wildlife conflict is a global issue. Attempts to manage this conflict impact upon wild animal welfare, an issue receiving little attention until relatively recently. Where human activities harm animal welfare these effects should be minimised where possible. However, little is known about the welfare impacts of different wildlife management interventions, and opinions on impacts vary widely. Welfare impacts therefore need to be assessed objectively. Our objectives were to: 1) establish whether an existing welfare assessment model could differentiate and rank the impacts of different wildlife management interventions (for decision-making purposes); 2) identify and evaluate any additional benefits of making formal welfare assessments; and 3) illustrate issues raised by application of the model. We applied the welfare assessment model to interventions commonly used with rabbits (Oryctolagus cuniculus), moles (Talpa europaea) and crows (Corvus corone) in the UK. The model ranked interventions for rabbits (least impact first: fencing, head shot, chest shot) and crows (shooting, scaring, live trapping with cervical dislocation). For moles, managing molehills and tunnels scored least impact. Both spring trapping, and live trapping followed by translocation, scored greater impacts, but these could not be compared directly as they scored on different axes of the model. Some rankings appeared counter-intuitive, highlighting the need for objective formal welfare assessments. As well as ranking the humaneness of interventions, the model highlighted future research needs and how Standard Operating Procedures might be improved. The model is a milestone in assessing wildlife management welfare impacts, but our research revealed some limitations of the model and we discuss likely challenges in resolving these. In future, the model might be developed to improve its utility, e.g. by refining the time-scales. It might also be used to reach consensus among stakeholders about

  3. Extended Postnatal Brain Development in the Longest-Lived Rodent: Prolonged Maintenance of Neotenous Traits in the Naked Mole-Rat Brain

    PubMed Central

    Orr, Miranda E.; Garbarino, Valentina R.; Salinas, Angelica; Buffenstein, Rochelle

    2016-01-01

    The naked mole-rat (NMR) is the longest-lived rodent with a maximum lifespan >31 years. Intriguingly, fully-grown naked mole-rats (NMRs) exhibit many traits typical of neonatal rodents. However, little is known about NMR growth and maturation, and we question whether sustained neotenous features when compared to mice, reflect an extended developmental period, commensurate with their exceptionally long life. We tracked development from birth to 3 years of age in the slowest maturing organ, the brain, by measuring mass, neural stem cell proliferation, axonal, and dendritic maturation, synaptogenesis and myelination. NMR brain maturation was compared to data from similar sized rodents, mice, and to that of long-lived mammals, humans, and non-human primates. We found that at birth, NMR brains are significantly more developed than mice, and rather are more similar to those of newborn primates, with clearly laminated hippocampi and myelinated white matter tracts. Despite this more mature brain at birth than mice, postnatal NMR brain maturation occurs at a far slower rate than mice, taking four-times longer than required for mice to fully complete brain development. At 4 months of age, NMR brains reach 90% of adult size with stable neuronal cytostructural protein expression whereas myelin protein expression does not plateau until 9 months of age in NMRs, and synaptic protein expression continues to change throughout the first 3 years of life. Intriguingly, NMR axonal composition is more similar to humans than mice whereby NMRs maintain expression of three-repeat (3R) tau even after brain growth is complete; mice experience an abrupt downregulation of 3R tau by postnatal day 8 which continues to diminish through 6 weeks of age. We have identified key ages in NMR cerebral development and suggest that the long-lived NMR may provide neurobiologists an exceptional model to study brain developmental processes that are compressed in common short-lived laboratory animal models

  4. Assessing Animal Welfare Impacts in the Management of European Rabbits (Oryctolagus cuniculus), European Moles (Talpa europaea) and Carrion Crows (Corvus corone).

    PubMed

    Baker, Sandra E; Sharp, Trudy M; Macdonald, David W

    2016-01-01

    Human-wildlife conflict is a global issue. Attempts to manage this conflict impact upon wild animal welfare, an issue receiving little attention until relatively recently. Where human activities harm animal welfare these effects should be minimised where possible. However, little is known about the welfare impacts of different wildlife management interventions, and opinions on impacts vary widely. Welfare impacts therefore need to be assessed objectively. Our objectives were to: 1) establish whether an existing welfare assessment model could differentiate and rank the impacts of different wildlife management interventions (for decision-making purposes); 2) identify and evaluate any additional benefits of making formal welfare assessments; and 3) illustrate issues raised by application of the model. We applied the welfare assessment model to interventions commonly used with rabbits (Oryctolagus cuniculus), moles (Talpa europaea) and crows (Corvus corone) in the UK. The model ranked interventions for rabbits (least impact first: fencing, head shot, chest shot) and crows (shooting, scaring, live trapping with cervical dislocation). For moles, managing molehills and tunnels scored least impact. Both spring trapping, and live trapping followed by translocation, scored greater impacts, but these could not be compared directly as they scored on different axes of the model. Some rankings appeared counter-intuitive, highlighting the need for objective formal welfare assessments. As well as ranking the humaneness of interventions, the model highlighted future research needs and how Standard Operating Procedures might be improved. The model is a milestone in assessing wildlife management welfare impacts, but our research revealed some limitations of the model and we discuss likely challenges in resolving these. In future, the model might be developed to improve its utility, e.g. by refining the time-scales. It might also be used to reach consensus among stakeholders about

  5. Extended Postnatal Brain Development in the Longest-Lived Rodent: Prolonged Maintenance of Neotenous Traits in the Naked Mole-Rat Brain.

    PubMed

    Orr, Miranda E; Garbarino, Valentina R; Salinas, Angelica; Buffenstein, Rochelle

    2016-01-01

    The naked mole-rat (NMR) is the longest-lived rodent with a maximum lifespan >31 years. Intriguingly, fully-grown naked mole-rats (NMRs) exhibit many traits typical of neonatal rodents. However, little is known about NMR growth and maturation, and we question whether sustained neotenous features when compared to mice, reflect an extended developmental period, commensurate with their exceptionally long life. We tracked development from birth to 3 years of age in the slowest maturing organ, the brain, by measuring mass, neural stem cell proliferation, axonal, and dendritic maturation, synaptogenesis and myelination. NMR brain maturation was compared to data from similar sized rodents, mice, and to that of long-lived mammals, humans, and non-human primates. We found that at birth, NMR brains are significantly more developed than mice, and rather are more similar to those of newborn primates, with clearly laminated hippocampi and myelinated white matter tracts. Despite this more mature brain at birth than mice, postnatal NMR brain maturation occurs at a far slower rate than mice, taking four-times longer than required for mice to fully complete brain development. At 4 months of age, NMR brains reach 90% of adult size with stable neuronal cytostructural protein expression whereas myelin protein expression does not plateau until 9 months of age in NMRs, and synaptic protein expression continues to change throughout the first 3 years of life. Intriguingly, NMR axonal composition is more similar to humans than mice whereby NMRs maintain expression of three-repeat (3R) tau even after brain growth is complete; mice experience an abrupt downregulation of 3R tau by postnatal day 8 which continues to diminish through 6 weeks of age. We have identified key ages in NMR cerebral development and suggest that the long-lived NMR may provide neurobiologists an exceptional model to study brain developmental processes that are compressed in common short-lived laboratory animal models.

  6. Improving the Modelled Global Terrestrial Carbon Cycle by Assimilating CO2 Mole Fractions and FAPAR with the MPI Carbon Cycle Data Assimilation System (MPI-CCDAS)

    NASA Astrophysics Data System (ADS)

    Schürmann, Gregor; Köstler, Christoph; Kaminski, Thomas; Giering, Ralf; Scholze, Marko; Kattge, Jens; Carvalhais, Nuno; Voßbeck, Michael; Rödenbeck, Christian; Reick, Christian; Zaehle, Sönke

    2015-04-01

    Long-term monitoring of ecosystem carbon fluxes and atmospheric CO2 concentrations provides independent observations of the land's carbon balance at different scales. However, the scale-gap between these observations makes a direct quantification of regional carbon balances based on these data impossible. Here, we describe first results of the MPI Carbon Cycle Data Assimilation System (MPI-CCDAS), designed to use multiple data streams at different scales to constrain parameters in the biosphere model JSBACH. We constrain the MPI-CCDAS with two complementary data-streams: CO2 mole fractions observed at a network of atmospheric monitoring stations, and remotely-sensed fraction of absorbed photosynthetically active radiation (TIP-FAPAR). The assimilation procedure greatly improves the representation of the seasonal cycle of atmospheric CO2, and reduces the global gross primary productivity (GPP) from 160 PgC/year to 118 PgC/year. Applying the MPI-CCDAS separately and jointly on both data streams allows to analyse the contribution of each data stream to the improved global carbon cycle model. Evaluation against independent carbon cycle estimates based on upscaled ecosystem flux measurements corroborates the adequacy of the model improvements, and demonstrates the utility of the CCDAS framework in consistently integrating carbon cycle data.

  7. Genome maintenance and bioenergetics of the long-lived hypoxia-tolerant and cancer-resistant blind mole rat, Spalax: a cross-species analysis of brain transcriptome.

    PubMed

    Malik, Assaf; Domankevich, Vered; Lijuan, Han; Xiaodong, Fang; Korol, Abraham; Avivi, Aaron; Shams, Imad

    2016-12-09

    The subterranean blind mole rat, Spalax, experiences acute hypoxia-reoxygenation cycles in its natural subterranean habitat. At the cellular level, these conditions are known to promote genomic instability, which underlies both cancer and aging. However, Spalax is a long-lived animal and is resistant to both spontaneous and induced cancers. To study this apparent paradox we utilized a computational procedure that allows detecting differences in transcript abundance between Spalax and the closely related above-ground Rattus norvegicus in individuals of different ages. Functional enrichment analysis showed that Spalax whole brain tissues maintain significantly higher normoxic mRNA levels of genes associated with DNA damage repair and DNA metabolism, yet keep significantly lower mRNA levels of genes involved in bioenergetics. Many of the genes that showed higher transcript abundance in Spalax are involved in DNA repair and metabolic pathways that, in other species, were shown to be downregulated under hypoxia, yet are required for overcoming replication- and oxidative-stress during the subsequent reoxygenation. We suggest that these differentially expressed genes may prevent the accumulation of DNA damage in mitotic and post-mitotic cells and defective resumption of replication in mitotic cells, thus maintaining genome integrity as an adaptation to acute hypoxia-reoxygenation cycles.

  8. N2 Mole Fraction Dependence of Plasma Bullet Propagation in Premixed He/N2 Plasma Needle Discharge at Atmospheric Pressure

    NASA Astrophysics Data System (ADS)

    Ni, Gengsong; Qian, Muyang; Yang, Congying; Liu, Sanqiu; Wang, Dezhen

    2016-07-01

    In this work, a computational modeling study on the mechanism of the acceleration behavior of a plasma bullet in needle-plane configuration is presented. Above all, in our model, two sub-models of time-dependent plasma dynamics and laminar flow are connected using a oneway coupled method, and both the working gas and the surrounding gas around the plasma jet are assumed to be the same, which are premixed He/N2 gas. The mole fractions of the N2 (NMF) ingredient are set to be 0.01%, 0.1% and 1% in three cases, respectively. It is found that in each case, the plasma bullet accelerates with time to a peak velocity after it exits the nozzle and then decreases until getting to the treated surface, and that the velocity of the plasma bullet increases at each time moment with the peak value changing from 0.72×106 m/s to 0.80×106 m/s but then drops more sharply when the NMF varies from 0.01% to 1%. Besides, the electron impact ionizations of helium neutrals and nitrogen molecules are found to have key influences on the propagation of a plasma bullet instead of the penning ionization. supported by National Natural Science Foundation of China (No. 11465013), the Natural Science Foundation of Jiangxi Province, China (No. 20151BAB212012), and in part by the International Science and Technology Cooperation Program of China (No. 2015DFA61800)

  9. Sex, Status, and Sand: California Academy of Sciences' Teen Interns Examine Trends of the Pacific Mole Crab (Emerita analoga) at Ocean Beach, San Francisco

    NASA Astrophysics Data System (ADS)

    Chu, J. B.; Conrad-Saydah, A.; Cohen, S.; Tom, R.; Robins-Moloney, M.; Masters, D.; Mason, K.; Alfaro, F.

    2003-12-01

    Student interns from the California Academy of Sciences' Careers in Sciences program monitored the Pacific mole crab (Emerita analoga), or sand crabs, in collaboration with the Farallones Marine Sanctuary Association. These small crustaceans live in the swash zone of the sandy beach habitat. Sand crabs are important in the food web, and therefore their status can help indicate the health of the larger environment. The interns helped the Gulf of the Farallones National Marine Sanctuary by monitoring the abundance and distribution of sand crabs at Ocean Beach in San Francisco, California. Students set up transects perpendicular to the shoreline, collected 10 samples along the transect, measured the carapace length, determined the sex of each crab, and checked for the presence of eggs. Students monitored June through September, 2003. Trends examined included differences in the gender ratio, size frequency, and distribution along the beach. Students also compared their data to other student data taken from other sites in San Francisco and Marin counties during 2001-2003 from the online database at http://www.sandcrabs.org. Using comparisons, interns were able to better understand the processes and significance of studying marine species. Implementation of the project was invaluable in aiding the interns in their understanding of the natural sciences and the role of monitoring habitats in environmental health.

  10. Microhabitat types promote the genetic structure of a micro-endemic and critically endangered mole salamander (Ambystoma leorae) of Central Mexico.

    PubMed

    Sunny, Armando; Monroy-Vilchis, Octavio; Reyna-Valencia, Carlos; Zarco-González, Martha M

    2014-01-01

    The reduced immigration and emigration rates resulting from the lack of landscape connectivity of patches and the hospitality of the intervening matrix could favor the loss of alleles through genetic drift and an increased chance of inbreeding. In order for isolated populations to maintain sufficient levels of genetic diversity and adapt to environmental changes, one important conservation goal must be to preserve or reestablish connectivity among patches in a fragmented landscape. We studied the last known population of Ambystoma leorae, an endemic and critically threatened species. The aims of this study were: (1) to assess the demographic parameters of A. leorae and to distinguish and characterize the microhabitats in the river, (2) to determine the number of existing genetic groups or demes of A. leorae and to describe possible relationships between microhabitats types and demes, (3) to determine gene flow between demes, and (4) to search for geographic locations of genetic discontinuities that limit gene flow between demes. We found three types of microhabitats and three genetically differentiated subpopulations with a significant level of genetic structure. In addition, we found slight genetic barriers. Our results suggest that mole salamander's species are very sensitive to microhabitat features and relatively narrow obstacles in their path. The estimates of bidirectional gene flow are consistent with the pattern of a stepping stone model between demes, where migration occurs between adjacent demes, but there is low gene flow between distant demes. We can also conclude that there is a positive correlation between microhabitats and genetic structure in this population.

  11. Facile synthesis of multi-shell structured binary metal oxide powders with a Ni/Co mole ratio of 1:2 for Li-Ion batteries

    NASA Astrophysics Data System (ADS)

    Choi, Seung Ho; Park, Sun Kyu; Lee, Jung-Kul; Kang, Yun Chan

    2015-06-01

    Multi-shell structured binary transition metal oxide powders with a Ni/Co mole ratio of 1:2 are prepared by a simple spray drying process. Precursor powder particles prepared by spray drying from a spray solution of citric acid and ethylene glycol have completely spherical shape, fine size, and a narrow size distribution. The precursor powders turn into multi-shell powders after a post heat-treatment at temperatures between 250 and 800 °C. The multi-shell structured powders are formed by repeated combustion and contraction processes. The multi-shell powders have mixed crystal structures of Ni1-xCo2O4-x and NiO phases regardless of the post-treatment temperature. The reversible capacities of the powders post-treated at 250, 400, 600, and 800 °C after 100 cycles are 584, 913, 808, and 481 mA h g-1, respectively. The low charge transfer resistance and high lithium ion diffusion rate of the multi-shell powders post-treated at 400 °C with optimum grain size result in superior electrochemical properties even at high current densities.

  12. Genome maintenance and bioenergetics of the long-lived hypoxia-tolerant and cancer-resistant blind mole rat, Spalax: a cross-species analysis of brain transcriptome

    PubMed Central

    Malik, Assaf; Domankevich, Vered; Lijuan, Han; Xiaodong, Fang; Korol, Abraham; Avivi, Aaron; Shams, Imad

    2016-01-01

    The subterranean blind mole rat, Spalax, experiences acute hypoxia-reoxygenation cycles in its natural subterranean habitat. At the cellular level, these conditions are known to promote genomic instability, which underlies both cancer and aging. However, Spalax is a long-lived animal and is resistant to both spontaneous and induced cancers. To study this apparent paradox we utilized a computational procedure that allows detecting differences in transcript abundance between Spalax and the closely related above-ground Rattus norvegicus in individuals of different ages. Functional enrichment analysis showed that Spalax whole brain tissues maintain significantly higher normoxic mRNA levels of genes associated with DNA damage repair and DNA metabolism, yet keep significantly lower mRNA levels of genes involved in bioenergetics. Many of the genes that showed higher transcript abundance in Spalax are involved in DNA repair and metabolic pathways that, in other species, were shown to be downregulated under hypoxia, yet are required for overcoming replication- and oxidative-stress during the subsequent reoxygenation. We suggest that these differentially expressed genes may prevent the accumulation of DNA damage in mitotic and post-mitotic cells and defective resumption of replication in mitotic cells, thus maintaining genome integrity as an adaptation to acute hypoxia-reoxygenation cycles. PMID:27934892

  13. Biomonitoring of the genotoxic effects and oxidative potentials of commercial edible dung beetles (Onitis sp.), grasshopper (Caelifera sp.) and mole crickets (Gryllotalpa sp.) in vitro.

    PubMed

    Koc, Kubra; Incekara, Umit; Turkez, Hasan

    2014-09-01

    In this investigation, the genotoxic and oxidative effects of water soluble extracts of dung beetles, flying grasshopper and mole crickets have been assessed on cultured human blood cells. The extracts were added to the culture tubes at 12 different concentrations (0-2000 ppm). Micronucleus test was used to monitor the DNA and the chromosomal damage produced by aqueous extracts in vitro. In addition, to assess the oxidative effects, total antioxidant capacity (TAC) and total oxidant status (TOS) levels were also measured. Our results indicated that these extracts did not show genotoxic effects at the tested concentrations. However, the extracts caused dose-dependent alterations in both TAC and TOS levels. Based on the findings, it was concluded that the studied insects can be consumed safely, but it is necessary to consider the cellular damages which are likely to appear depending on oxidative stress at higher concentrations. It has also been suggested that this in vitro approach for oxidative and genotoxicity assessments may be useful to evaluate the potential health risks of edible insects.

  14. Age-related changes in the proteostasis network in the brain of the naked mole-rat: Implications promoting healthy longevity.

    PubMed

    Triplett, Judy C; Tramutola, Antonella; Swomley, Aaron; Kirk, Jessime; Grimes, Kelly; Lewis, Kaitilyn; Orr, Miranda; Rodriguez, Karl; Cai, Jian; Klein, Jon B; Perluigi, Marzia; Buffenstein, Rochelle; Butterfield, D Allan

    2015-10-01

    The naked mole-rat (NMR) is the longest-lived rodent and possesses several exceptional traits: marked cancer resistance, negligible senescence, prolonged genomic integrity, pronounced proteostasis, and a sustained health span. The underlying molecular mechanisms that contribute to these extraordinary attributes are currently under investigation to gain insights that may conceivably promote and extend human health span and lifespan. The ubiquitin-proteasome and autophagy-lysosomal systems play a vital role in eliminating cellular detritus to maintain proteostasis and have been previously shown to be more robust in NMRs when compared with shorter-lived rodents. Using a 2-D PAGE proteomics approach, differential expression and phosphorylation levels of proteins involved in proteostasis networks were evaluated in the brains of NMRs in an age-dependent manner. We identified 9 proteins with significantly altered levels and/or phosphorylation states that have key roles involved in proteostasis networks. To further investigate the possible role that autophagy may play in maintaining cellular proteostasis, we examined aspects of the PI3K/Akt/mammalian target of rapamycin (mTOR) axis as well as levels of Beclin-1, LC3-I, and LC3-II in the brain of the NMR as a function of age. Together, these results show that NMRs maintain high levels of autophagy throughout the majority of their lifespan and may contribute to the extraordinary health span of these rodents. The potential of augmenting human health span via activating the proteostasis network will require further studies.

  15. Age-related Changes in the Proteostasis Network in the Brain of the Naked Mole-Rat: Implications Promoting Healthy Longevity

    PubMed Central

    Triplett, Judy C.; Tramutola, Antonella; Swomley, Aaron; Kirk, Jessime; Grimes, Kelly; Lewis, Kaitilyn; Orr, Miranda; Rodriguez, Karl; Cai, Jian; Klein, Jon B.; Perluigi, Marzia; Buffenstein, Rochelle; Butterfield, D. Allan

    2016-01-01

    The naked mole-rat (NMR) is the longest-lived rodent and possesses several exceptional traits: marked cancer resistance, negligible senescence, prolonged genomic integrity, pronounced proteostasis, and a sustained healthspan. The underlying molecular mechanisms that contribute to these extraordinary attributes are currently under investigation to gain insights that may conceivably promote and extended human healthspan and lifespan. The ubiquitin-proteasome and autophagy-lysosomal systems play a vital role in eliminating cellular detritus to maintain proteostasis and have been previously shown to be more robust in NMRs when compared to shorter-lived rodents. Using a 2-D PAGE proteomics approach, differential expression and phosphorylation levels of proteins involved in proteostasis networks were evaluated in the brains of NMRs in an age-dependent manner. We identified 9 proteins with significantly altered levels and/or phosphorylation states that have key roles involved in proteostasis networks. To further investigate the possible role that autophagy may play in maintaining cellular proteostasis, we examined aspects of the PI3K/Akt/mammalian target of rapamycin (mTOR) axis as well as levels of Beclin-1, LC3-I, and LC3-II in the brain of the NMR as a function of age. Together, these results show that NMRs maintain high levels of autophagy throughout the majority of their lifespan. PMID:26248058

  16. Hormonal and behavioural correlates of male dominance and reproductive status in captive colonies of the naked mole-rat, Heterocephalus glaber.

    PubMed Central

    Clarke, F M; Faulkes, C G

    1998-01-01

    Naked mole-rat colonies are societies with a high reproductive skew, breeding being restricted to one dominant female (the 'queen') and 1-3 males. Other colony members of both sexes are reproductively suppressed. Experimental removal of breeding males allowed us to investigate the relationship between urinary testosterone and cortisol, dominance rank, and male reproductive status. Dominance rank was strongly correlated with body weight, age, and urinary testosterone titres in males. No relationship between urinary cortisol levels and male reproductive status or dominance was found. Breeding males were among the highest-ranking, heaviest and oldest males in their respective colonies, and were succeeded by other high-ranking, large, old colony males. In contrast to females, no evidence of competition over breeding status was observed among males. Male-male agonism was low both before and after removal of breeders and mate guarding was not observed. The lower reproductive skew for males compared with female skew or queen control over male reproduction may explain why males compete less strongly than females over breeding status after removal of same-sexed breeders. PMID:9721687

  17. Microhabitat Types Promote the Genetic Structure of a Micro-Endemic and Critically Endangered Mole Salamander (Ambystoma leorae) of Central Mexico

    PubMed Central

    Sunny, Armando; Monroy-Vilchis, Octavio; Reyna-Valencia, Carlos; Zarco-González, Martha M.

    2014-01-01

    The reduced immigration and emigration rates resulting from the lack of landscape connectivity of patches and the hospitality of the intervening matrix could favor the loss of alleles through genetic drift and an increased chance of inbreeding. In order for isolated populations to maintain sufficient levels of genetic diversity and adapt to environmental changes, one important conservation goal must be to preserve or reestablish connectivity among patches in a fragmented landscape. We studied the last known population of Ambystoma leorae, an endemic and critically threatened species. The aims of this study were: (1) to assess the demographic parameters of A. leorae and to distinguish and characterize the microhabitats in the river, (2) to determine the number of existing genetic groups or demes of A. leorae and to describe possible relationships between microhabitats types and demes, (3) to determine gene flow between demes, and (4) to search for geographic locations of genetic discontinuities that limit gene flow between demes. We found three types of microhabitats and three genetically differentiated subpopulations with a significant level of genetic structure. In addition, we found slight genetic barriers. Our results suggest that mole salamander’s species are very sensitive to microhabitat features and relatively narrow obstacles in their path. The estimates of bidirectional gene flow are consistent with the pattern of a stepping stone model between demes, where migration occurs between adjacent demes, but there is low gene flow between distant demes. We can also conclude that there is a positive correlation between microhabitats and genetic structure in this population. PMID:25076052

  18. Ca2+ transport properties and determinants of anomalous mole fraction effects of single voltage-gated Ca2+ channels in hair cells from bullfrog saccule

    PubMed Central

    Rodriguez-Contreras, Adrian; Nonner, Wolfgang; Yamoah, Ebenezer N

    2002-01-01

    We studied the permeation properties of two distinct single voltage-gated Ca2+ channels in bullfrog saccular hair cells to assess the roles of the channels as physiological Ca2+ transporters and multi-ion pores. By varying the permeant ions (Ba2+, Ca2+) and concentrations (2–70 mm), we estimated the affinity constant (KD) of the two channels as follows (mm): L-type channel, KD,Ba = 7.4 ± 1.0, KD,Ca = 7.1 ± 2.2 (n = 7); non-L-type channel, KD,Ba = 5.3 ± 3.2, KD,Ca = 2.0 ± 1.0 (n = 8). Using ionic concentrations close to physiological conditions (2 mm Ca2+ and 1.0 mm Mg2+), the conductance of the L-type channel was ∼2 pS. We determined the mechanisms by which ions traverse the pore of these single Ca2+ channels, using mixtures of Ba2+ and Ca2+ at total concentrations above (70 mm) or close to (5 mm) the KD of the channels. We found evidence for an anomalous mole fraction effect (AMFE) only when the total divalent ion concentration was 5 mm, consistent with a multi-ion pore. We show that AMFE arises from the boundaries between the pore and bulk solution in the atria of the channel, which is derived from the presence of depletion zones that become apparent at low divalent cation concentrations. The present findings provide an explanation as to why previous whole-cell Ca2+ currents that were recorded in quasi-physiological Ca2+ concentrations (∼2–5 mm) showed clear AMFE, whereas single Ca2+ channel currents that were recorded routinely at high Ca2+ concentrations (20–110 mm) did not. PMID:11826161

  19. Tunable diode laser absorption spectroscopy-based tomography system for on-line monitoring of two-dimensional distributions of temperature and H{sub 2}O mole fraction

    SciTech Connect

    Xu, Lijun Liu, Chang; Jing, Wenyang; Cao, Zhang; Xue, Xin; Lin, Yuzhen

    2016-01-15

    To monitor two-dimensional (2D) distributions of temperature and H{sub 2}O mole fraction, an on-line tomography system based on tunable diode laser absorption spectroscopy (TDLAS) was developed. To the best of the authors’ knowledge, this is the first report on a multi-view TDLAS-based system for simultaneous tomographic visualization of temperature and H{sub 2}O mole fraction in real time. The system consists of two distributed feedback (DFB) laser diodes, a tomographic sensor, electronic circuits, and a computer. The central frequencies of the two DFB laser diodes are at 7444.36 cm{sup −1} (1343.3 nm) and 7185.6 cm{sup −1} (1391.67 nm), respectively. The tomographic sensor is used to generate fan-beam illumination from five views and to produce 60 ray measurements. The electronic circuits not only provide stable temperature and precise current controlling signals for the laser diodes but also can accurately sample the transmitted laser intensities and extract integrated absorbances in real time. Finally, the integrated absorbances are transferred to the computer, in which the 2D distributions of temperature and H{sub 2}O mole fraction are reconstructed by using a modified Landweber algorithm. In the experiments, the TDLAS-based tomography system was validated by using asymmetric premixed flames with fixed and time-varying equivalent ratios, respectively. The results demonstrate that the system is able to reconstruct the profiles of the 2D distributions of temperature and H{sub 2}O mole fraction of the flame and effectively capture the dynamics of the combustion process, which exhibits good potential for flame monitoring and on-line combustion diagnosis.

  20. Changes in prevalence and intensity of infection of Profilicollis altmani (Perry, 1942) cystacanth (Acanthocephala) parasitizing the mole crab Emerita analoga (Stimpson, 1857): an El Niño cascade effect?

    NASA Astrophysics Data System (ADS)

    Oliva, Marcelo E.; Barrios, Irene; Thatje, Sven; Laudien, Jürgen

    2008-03-01

    Prevalence and intensity changes in cystacanths of the acanthocephalan Profilicollis altmani parasitizing the mole crab Emerita analoga under El Niño (EN) and non-El Niño (non-EN) conditions are analyzed. Both, mean intensity and prevalence of infection by P. altmani differ significantly for the whole size range and for each size class of 10 mm intervals (except prevalence for size classes exceeding 18 mm carapace length) between EN (1998) and non-EN (2002) years, without observed size distribution differences in the intermediate host E. analoga under either condition. Significant difference in infestation rates of the intermediate host E. analoga is discussed as being an EN cascade effect on predators such as sea birds (i.e., Larus spp. and Calidris sp.), acting as definitive hosts of P. altmani, and which are known to decrease significantly in abundance during EN.

  1. Tenrec phylogeny and the noninvasive extraction of nuclear DNA.

    PubMed

    Asher, Robert J; Hofreiter, Michael

    2006-04-01

    Due in part to scarcity of material, no published study has yet cladistically addressed the systematics of living and fossil Tenrecidae (Mammalia, Afrotheria). Using a noninvasive technique for sampling nuclear DNA from museum specimens, we investigate the evolution of the Tenrecidae and assess the extent to which tenrecids fit patterns of relationships proposed for other terrestrial mammals on Madagascar. Application of several tree-reconstruction techniques on sequences of the nuclear growth hormone receptor gene and morphological data for all recognized tenrecid genera supports monophyly of Malagasy tenrecids to the exclusion of the two living African genera. However, both parsimony and Bayesian methods favor a close relationship between fossil African tenrecs and the Malagasy Geogale, supporting the hypothesis of island paraphyly, but not polyphyly. More generally, the noninvasive extraction technique can be applied with minimal risk to rare/unique specimens and, by better utilizing museum collections for genetic work, can greatly mitigate field expenses and disturbance of natural populations.

  2. Lack of sexual dimorphism in femora of the eusocial and hypogonadic naked mole-rat: a novel animal model for the study of delayed puberty on the skeletal system.

    PubMed

    Pinto, M; Jepsen, K J; Terranova, C J; Buffenstein, R

    2010-01-01

    Sex steroid hormones are major determinants of bone morphology and quality and are responsible for sexually dimorphic skeletal traits. Hypogonadism results in suboptimal skeletal development and may lead to an increased risk of bone fracture later in life. The etiology of delayed puberty and/or hypothalamic amenorrhea is poorly understood, and experimental animal models addressing this issue are predominantly based upon short-term experimental induction of hormonal suppression via gonadotropin releasing hormone antagonists (GnRH-a). This acute change in hormone profile does not necessarily emulate the natural progression of hypogonadic bone disorders. We propose a novel animal model with which to explore the effects of chronic hypogonadism on bone quality, the naked mole-rat (NMR; Heterocephalus glaber). This mouse-size rodent may remain reproductively suppressed throughout its life, if it remains as a subordinate within the eusocial mole-rat colony. NMRs live in large colonies with a single dominant breeding female. She, primarily by using aggressive social contact, naturally suppresses the hypothalamic gonadotropic axis of subordinate NMRs and thereby their reproductive expression. However, should an NMR be separated from the dominant breeder, within less than a week reproductive hormones may become elevated and the animal attains breeding status. We questioned if sexual suppression of subordinates impact upon the development and maintenance of the femora and lead to a sexually indistinct monomorphic skeleton. Femora were obtained from male and female NMRs that were either non-breeders (subordinate) or breeders at the time of sacrifice. Diaphyseal cross-sectional morphology, metaphyseal trabecular micro-architecture and tissue mineral density of the femur were measured using microcomputed tomography and diaphyseal mechanical properties were assessed by four-point bending tests to failure. Subordinates were sexually monomorphic and showed no significant

  3. Composition and carrier-concentration dependence of the electronic structure of InyGa1-yAs1-xNx films with nitrogen mole fraction of less than 0.012

    NASA Astrophysics Data System (ADS)

    Kang, Youn-Seon; Robins, Lawrence H.; Birdwell, Anthony G.; Shapiro, Alexander J.; Thurber, W. Robert; Vaudin, Mark D.; Fahmi, M. M. E.; Bryson, Damian; Mohammad, S. Noor

    2005-11-01

    The electronic structure of Si-doped InyGa1-yAs1-xNx films on GaAs substrates, grown by nitrogen-plasma-assisted molecular-beam epitaxy, was examined by photoreflectance (PR) spectroscopy at temperatures between 20 and 300 K. The films were approximately 0.5 μm thick and had nitrogen mole fraction between x=0.0014 and x=0.012, measured indirectly by a secondary-ion-mass spectrometry calibration; indium mole fraction between y=0.052 and y=0.075, measured by electron-dispersive x-ray spectroscopy; and carrier concentration between 2×1016 and 1.1×1018 cm-3, measured by Hall effect. Three critical-point transitions were identified by PR: the fundamental band gap (highest valence band to the lowest conduction band); the spin-orbit split valence band to the lowest conduction band; and the highest valence band to a nitrogen impurity band (above the lowest conduction band). The measured critical-point energies were described by a band anticrossing (BAC) model with the addition of a Burstein-Moss band-filling term. The fitted BAC parameters were similar to previously reported values. The N impurity level was located 0.3004+/-0.0101 eV above the conduction-band edge at 20 K and 0.3286+/-0.0089 eV above the conduction-band edge at 295 K. The BAC interaction parameter was 2.588+/-0.071 eV. From the small magnitude of the Burstein-Moss energy shift with increasing carrier concentration, it was inferred that the carrier concentration probed by PR is reduced from the bulk (Hall-effect) carrier concentration by a reduction factor of 0.266+/-0.145. The PR lines broadened with increasing carrier concentration; the line broadening tracked the predicted Burstein-Moss energy shift for the bulk carrier concentration. The surface-normal lattice constants of the films were measured by x-ray diffraction. Comparison of the measured lattice constants with Vegard's law showed the presence of tensile strain (in the surface-normal direction) with magnitude between 1.5×10-3 and 3.0×10

  4. Engineering cellulase mixtures by varying the mole fraction of Thermomonospora fusca E[sub 5] and E[sub 3], Trichoderma reesei CBHI, and Caldocellum saccharolyticum [beta]-glucosidase

    SciTech Connect

    Walker, L.P.; Belair, C.D.; Wilson, D.B.; Irwin, D.C. )

    1993-11-05

    In this study, different mole fractions of pure Thermomonospora fusca E[sub 5] and E[sub 3], plus Trichoderma reesei CBHI were studied for reducing sugar production at 2 h, degree of synergism, and cellulose binding. In addition, the effects of introducing the Caldocellum saccharolyticum [Beta]-glucosidase into this cellulase system were investigated. The cellulases used were purified to homogeneity. Avicel PH 102 was the substrate. Reactions were run at 50 C for 2 h using total cellulase concentrations of 8.3 or 12.2 [mu]M. A bimixture of T. fusca E[sub 3] and T. reesei CBHI was very effective in hydrolyzing microcrystalline cellulose. The addition of endoglucanase E[sub 5] to the mixture only increased conversion to 9.8%. However, when both E[sub 5] and [Beta]-glucosidase were added, conversion increased to 14%. It was also observed that increasing total cellulase concentration beyond 8.3 [mu]M did little to increase percent conversion of cellulose into glucose. The results of the binding studies indicate no competition for binding sites between the endo- and exocellulases.

  5. Lattice-engineered MBE growth of high-indium mole fraction InGaAs for low cost MMICs and (1.3--1.55 {micro}m) OEICs

    SciTech Connect

    Childs, T.T.; Sokolov, V.; Sullivan, C.T.

    1997-11-01

    Using molecular beam epitaxy (MBE) and lattice engineering techniques, the feasibility of combining photonic devices applicable to the 1.3 to 1.55 {micro}m wavelength range and monolithic microwave (or mm-wave) integrated circuits (MMICs) on GaAs is demonstrated. A key factor in the MBE growth is incorporation of an InGaAs active layer having an indium arsenide mole fraction of 0.35 or greater and its lattice compatibility with the underlying semi-insulating GaAs substrate. The InGaAs layer used for the photonic devices, can also serve as the active channel for the high electron mobility transistors (HEMTs) for application in MMICs. Several examples of active and passive photonic devices grown by MBE are presented including an optical ridge waveguide, and a photodetector for detection of light in the 1.3 {micro}m range. The material structure includes a 3-layer AlGaAs/GaAs/AlGaAs optical waveguide and a thin InGaAs absorbing layer situated directly above the optical waveguide. Metal-semiconductor-metal (MSM) photodetectors are formed on the top surface of the InGaAs layer for collection of the photo-induced carriers. The optical ridge waveguide is designed for lateral incidence of the light to enhance the MSM photodetector responsivity. Initial measurements on the optical waveguide and photodetector are presented.

  6. H2O2 treatment or serum deprivation induces autophagy and apoptosis in naked mole-rat skin fibroblasts by inhibiting the PI3K/Akt signaling pathway.

    PubMed

    Zhao, Shanmin; Li, Li; Wang, Shiyong; Yu, Chenlin; Xiao, Bang; Lin, Lifang; Cong, Wei; Cheng, Jishuai; Yang, Wenjing; Sun, Wei; Cui, Shufang

    2016-12-20

    Naked mole-rats (NMR; Heterocephalus glaber) display extreme longevity and resistance to cancer. Here, we examined whether autophagy contributes to the longevity of NMRs by assessing the effects of the PI3K/Akt pathway inhibitor LY294002 and the autophagy inhibitor chloroquine (CQ) on autophagy and apoptosis in NMR skin fibroblasts. Serum starvation, H2O2 treatment, and LY294002 treatment all increased the LC3-II/LC3-I ratio and numbers of double-membraned autophagosomes and autophagic vacuoles, and decreased levels of p70S6K, p-AktSer473, and p-AktThr308. By contrast, CQ treatment decreased p70S6K, AktSer473, and AktThr308 levels. The Bax/Bcl-2 ratio increased after 12 h of exposure to LY294002 or CQ. These data show that inhibiting the Akt pathway promotes autophagy and apoptosis in NMR skin fibroblasts. Furthermore, LY294002 or CQ treatment decreased caspase-3, p53, and HIF1-α levels, suggesting that serum starvation or H2O2 treatment increase autophagy and apoptosis in NMR skin fibroblasts by inhibiting the PI3K/Akt pathway. CQ-induced inhibition of late autophagy stages also prevented Akt activation and induced apoptosis. Finally, the HIF-1α and p53 pathways were involved in serum starvation- or H2O2-induced autophagy in NMR skin fibroblasts.

  7. Arthritis in a glyptodont (Mammalia, Xenarthra, Cingulata).

    PubMed

    Barbosa, Fernando Henrique de Souza; Porpino, Kleberson de Oliveira; Fragoso, Ana Bernadete Lima; Oliveira, Edison Vicente

    2014-01-01

    Arthritic lesions have been frequently diagnosed in the fossil record, with spondyloarthropathy (a type of erosive and pan-mammalian arthritis) being one of the most common types described to date for mammals, though not restricted to this group. Here, we identify spondyloarthropathy in fossil bones from the late Pleistocene in Brazil assignable to a large glyptodont individual. Bone erosions in the peripheral joints (viz., the ulna, radius, left femur and tibiae-fibulae) associated with osteosclerosis allow the diagnosis of spondyloarthropathy. The presence of osteophytes in seven bones of the forelimbs (viz., the ulna and radius) and hind limbs (viz., the tibiae-fibulae, left femur and patellae) and a subchondral cyst in one element (viz., the left femur) indicate secondary osteoarthritis. A calcified deposition on the articular surface of the left patella indicates the presence of calcium pyrophosphate deposition disease, which, like the observed osteoarthritic alterations, likely represents a complication of spondyloarthropathy. This is the first report of spondyloarthropathy for xenarthrans.

  8. The entotympanic in late fetal Artiodactyla (Mammalia).

    PubMed

    Maier, Wolfgang

    2013-08-01

    The entotympanic is a neomorphic component of the bulla tympanica of placental mammals. Ontogenetically, its rostral component seems to be derived from the tubal cartilage, whereas its caudal component is normally connected with the sheath of the tympanohyal; the present study indicates additional sources of the caudal entotympanic. The entotympanics develop in late fetal or early postnatal life as cartilaginous structures, but in most taxa they ossifiy endochondrally as "os bullae". This skeletal element is absent only in a few placental orders, among them the Artiodactyla. Because it is present in their sister taxa within the Scrotifera, it is likely to be reduced secondarily in the even-toed mammals. The study of histological serial sections of late fetal stages of several artiodactyl species shows that vestigial cartilaginous homologues of the entotympanics are invariably present, contrary to statements in the literature. In a few perinatal stages even secondary ossifications or calcifications of the entotympanic cartilages can be observed. The tubal cartilage of artiodactyls also continues into an anterior tegmen tympani (new term) that forms the floor of the fossa muscularis major.

  9. What Does a Mole Look Like?

    MedlinePlus

    ... Resources Conducting Clinical Trials Statistical Tools and Data Terminology Resources NCI Data Catalog Cryo-EM NCI's Role ... Report (RPPR) Grant Closeout Grant Resources NCI Grants Management Legal Requirements NCI Grant Policies Grants Management Contacts ...

  10. Distribution of parvalbumin, calbindin and calretinin containing neurons and terminal networks in relation to sleep associated nuclei in the brain of the giant Zambian mole-rat (Fukomys mechowii).

    PubMed

    Bhagwandin, Adhil; Gravett, Nadine; Bennett, Nigel C; Manger, Paul R

    2013-09-01

    To broaden the understanding of the neural control and evolution of the sleep-wake cycle in mammals, the distribution and interrelations of sleep associated nuclei with neurons and terminal networks expressing the calcium-binding proteins parvalbumin, calbindin and calretinin were explored in a rodent that lacks a significant visual system. The sleep-associated nuclei explored include the cholinergic basal forebrain and pontine nuclei, the catecholaminergic locus coeruleus complex, the serotonergic dorsal raphe nuclear complex, the hypothalamic orexinergic nuclei, and the thalamic reticular nucleus. Zambian mole-rat brains were sectioned and stained in a one in nine series for Nissl, myelin, choline acetyltransferase (ChAT), tyrosine hydroxylase (TH), serotonin (5HT), orexin (OrxA), calbindin (CB), calretinin (CR) and parvalbumin (PV). We observed that while the density of immunopositive calbindin (CB+) neurons and terminal networks varied in the different sleep related nuclei, they were found in all nuclei apart from the compact and diffuse subdivisions of the subcoeruleus, which lacked CB+ neurons but evinced a CB+ terminal network. The density of calretinin immunopositive (CR+) neurons and terminal networks varied between the sleep related nuclei, but was present in all nuclei examined. Neurons and terminal networks associated with PV immunoreactivity were the most sparsely distributed in these nuclei, but were present in the majority of nuclei. The thalamic reticular nucleus had the highest density of PV+ neurons and terminal networks, while PV+ neurons were absent in the cholinergic pontine nuclei, and PV+ neurons and terminal networks were absent in the orexinergic nuclei. The increased presence of neurons and terminal networks expressing the calcium binding proteins in comparison to that seen in the laboratory rat, specifically in the brainstem, may account for the prominent muscle twitches during REM sleep previously observed in this subterranean African

  11. Non-image Forming Light Detection by Melanopsin, Rhodopsin, and Long-Middlewave (L/W) Cone Opsin in the Subterranean Blind Mole Rat, Spalax Ehrenbergi: Immunohistochemical Characterization, Distribution, and Connectivity

    PubMed Central

    Esquiva, Gema; Avivi, Aaron; Hannibal, Jens

    2016-01-01

    The blind mole rat, Spalax ehrenbergi, can, despite severely degenerated eyes covered by fur, entrain to the daily light/dark cycle and adapt to seasonal changes due to an intact circadian timing system. The present study demonstrates that the Spalax retina contains a photoreceptor layer, an outer nuclear layer (ONL), an outer plexiform layer (OPL), an inner nuclear layer (INL), an inner plexiform layer (IPL), and a ganglion cell layer (GCL). By immunohistochemistry, the number of melanopsin (mRGCs) and non-melanopsin bearing retinal ganglion cells was analyzed in detail. Using the ganglion cell marker RNA-binding protein with multiple splicing (RBPMS) it was shown that the Spalax eye contains 890 ± 62 RGCs. Of these, 87% (752 ± 40) contain melanopsin (cell density 788 melanopsin RGCs/mm2). The remaining RGCs were shown to co-store Brn3a and calretinin. The melanopsin cells were located mainly in the GCL with projections forming two dendritic plexuses located in the inner part of the IPL and in the OPL. Few melanopsin dendrites were also found in the ONL. The Spalax retina is rich in rhodopsin and long/middle wave (L/M) cone opsin bearing photoreceptor cells. By using Ctbp2 as a marker for ribbon synapses, both rods and L/M cone ribbons containing pedicles in the OPL were found in close apposition with melanopsin dendrites in the outer plexus suggesting direct synaptic contact. A subset of cone bipolar cells and all photoreceptor cells contain recoverin while a subset of bipolar and amacrine cells contain calretinin. The calretinin expressing amacrine cells seemed to form synaptic contacts with rhodopsin containing photoreceptor cells in the OPL and contacts with melanopsin cell bodies and dendrites in the IPL. The study demonstrates the complex retinal circuitry used by the Spalax to detect light, and provides evidence for both melanopsin and non-melanopsin projecting pathways to the brain. PMID:27375437

  12. The physical hydrology of magmatic-hydrothermal systems: High-resolution 18O records of magmatic-meteoric water interaction from the Yankee Lode tin deposit (Mole Granite, Australia)

    NASA Astrophysics Data System (ADS)

    Fekete, Szandra; Weis, Philipp; Driesner, Thomas; Heinrich, Christoph A.; Baumgartner, Lukas; Bouvier, Anne-Sophie

    2016-04-01

    Magmatic-hydrothermal ore deposits are important economic Cu, Au, Mo and Sn resources (Sillitoe, 2010, Kesler, 1994). The ore formation is a result of superimposed enrichment processes and metals can precipitate due to fluid-rock interaction and/or temperature drop caused by convection or mixing with meteoric fluid (Heinrich and Candela 2014). Microthermometry and LA-ICP MS trace element analyses of fluid inclusions of a well-characterized quartz sample from the Yankee Lode quartz-cassiterite vein deposit (Mole Granite, Australia) suggest that tin precipitation was driven by dilution of hot magmatic water by meteoric fluids (Audétat et al.1998). High resolution in situ oxygen isotope measurements of quartz have the potential to detect changing fluid sources during the evolution of a hydrothermal system. We analyzed the euhedral growth zones of this previously well-studied quartz sample. Growth temperatures are provided by Audétat et al. (1998) and Audétat (1999). Calculated δ 18O values of the quartz- and/or cassiterite-precipitating fluid show significant variability through the zoned crystal. The first and second quartz generations (Q1 and Q2) were precipitated from a fluid of magmatic isotopic composition with δ 18O values of ˜ 8 - 10 ‰. δ 18O values of Q3- and tourmaline-precipitating fluids show a transition from magmatic δ 18O values of ˜ 8 ‰ to ˜ -5 ‰. The outermost quartz-chlorite-muscovite zone was precipitated from a fluid with a significant meteoric water component reflected by very light δ 18O values of about -15 ‰ which is consistent with values found by previous studies (Sun and Eadington, 1987) using conventional O-isotope analysis of veins in the distal halo of the granite intrusion. Intense incursion of meteoric water during Q3 precipitation (light δ 18O values) agrees with the main ore formation event, though the first occurrence of cassiterite is linked to Q2 precipitating fluid with magmatic-like isotope signature. This

  13. The management and outcome of women with post-hydatidiform mole ‘low-risk' gestational trophoblastic neoplasia, but hCG levels in excess of 100 000 IU l−1

    PubMed Central

    McGrath, S; Short, D; Harvey, R; Schmid, P; Savage, P M; Seckl, M J

    2010-01-01

    Background: Gestational trophoblastic neoplasia (GTN) after a hydatidiform mole is either treated with single- or multi-agent chemotherapy determined by a multifactorial scoring system. Women with human chorionic gonadotrophin (hCG) levels >100 000 IU l−1 can remain within the low-risk/single-agent category and usually choose one drug therapy. Here we compare the success and duration of single- vs multi-agent chemotherapy in this patient group. Methods: Between 1980 and 2008, 65 women had a pre-treatment hCG >100 000 IU l−1 and were low risk. The initial hCG level, treatment regimens, changes and duration and overall survival were recorded. Results: Of 37 patients starting low-risk/single-agent treatment, 11 (29.7%) were treated successfully, whereas 26 (70.3%) required additional multi-agent chemotherapy to achieve complete remission (CR). Combination chemotherapy was initially commenced in 28 women, and 2 (7%) required additional drugs for CR. The overall duration of therapy for those commencing and completing single- or multi-agent chemotherapy was 130 and 123 days (P=0.78), respectively. The median-treatment duration for patients commencing single-agent but changing to multi-agent chemotherapy was 13 days more than those receiving high-risk treatment alone (136 vs 123 days; P=0.07). All 3 patients with an initial hCG >400 000 IU l−1 and treated with single-agent therapy developed drug resistance. Overall survival for all patients was 100%. Conclusion: Low-risk post-molar GTN patients with a pre-treatment hCG >100 000 and <400 000 IU l−1 can be offered low-risk single-agent therapy, as this will cure 30%, is relatively non-toxic and only prolongs treatment by 2 weeks if a change to combination agents is required. Patients whose hCG is >400 000 IU l−1 should receive multi-agent chemotherapy from the outset. PMID:20160727

  14. The influences of mole composition of strontium (x) on properties of barium strontium titanate (Ba{sub 1−x}Sr{sub x}TiO{sub 3}) prepared by solid state reaction method

    SciTech Connect

    Sandi, Dianisa Khoirum; Supriyanto, Agus; Iriani, Yofentina; Jamaluddin, Anif

    2016-02-08

    Barium Strontium Titanate (Ba{sub 1-x}Sr{sub x}TiO{sub 3}) or BST was prepared by solid state reaction method. Raw materials are BaCO{sub 3}, SrCO{sub 3}, and TiO{sub 2}. Those materials are mixed for 8 h, pressed, and sintered at temperature 1200°C for 2 h. Mole composition of Sr (x) was varied to study its influences on structural, morphological, and electrical properties of BST. Variation of (x) are x = 0; x = 0.1; and x = 0.5. XRD patterns showed a single phase of BST, which mean that mixture of raw materials was homogenous. Crystal structure was influenced by x. BaTiO{sub 3} and Ba{sub 0.9}Ti{sub 0.1}TiO{sub 3} have tetragonal crystal structure, while Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} is cubic. The diffraction angle shifted to right side (angle larger) as the increases of x. Crystalline size of BaTiO{sub 3}, Ba{sub 0.9}Sr{sub 0.1}TiO{sub 3}, and Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} are 38.13 nm; 38.62 nm; and 37.13 nm, respectively. SEM images showed that there are still of pores which were influenced by x. Ba{sub 0.9}Sr{sub 0.1}TiO{sub 3} has densest surface (pores are few and small in size). Sawyer Tower circuit showed that BaTiO{sub 3} and Ba{sub 0.9}Sr{sub 0.1} TiO{sub 3} is ferroelectric, while Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} is paraelectric. The dielectric constants of BaTiO{sub 3}, Ba{sub 0.9}Sr{sub 0.1}TiO{sub 3} and Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} at frequency of 1 KHz are 156; 196; and 83, respectively. Ba{sub 0.9}Sr{sub 0.1}TiO{sub 3} has relatively highest dielectric constant. It is considered that Ba{sub 0.9}Sr{sub 0.1}TiO{sub 3} has densest surface.

  15. Mole Pi: Using New Technology to Teach the Magnitude of a Mole

    ERIC Educational Resources Information Center

    Geyer, Michael J.

    2014-01-01

    A modified technique for demonstrating the magnitude of Avogadro's number using a new Raspberry Pi computer and the Python language is described. The technique also provides students the opportunity to review dimensional analysis.

  16. Molecular phylogenetic evidence confirming the Eulipotyphla concept and in support of hedgehogs as the sister group to shrews.

    PubMed

    Douady, Christophe J; Chatelier, Pascale I; Madsen, Ole; de Jong, Wilfried W; Catzeflis, Francois; Springer, Mark S; Stanhope, Michael J

    2002-10-01

    For more than a century, living insectivore-like mammals have been viewed as little removed from the ancestral mammalian stock based on their retention of numerous primitive characteristics. This circumstance has made "insectivores" a group of special interest in the study of mammalian evolution. included hedgehogs, moles, shrews, solenodons, golden moles, tenrecs, flying lemurs, tree shrews, and elephant shrews in Insectivora. Subsequently, morphologists excluded flying lemurs, tree shrews, and elephant shrews from Insectivora and placed these taxa in the orders Dermoptera, Scandentia, and Macroscelidea, respectively. The remaining insectivores constitute Lipotyphla, which is monophyletic based on morphology. In contrast, molecular data suggest that lipotyphlans are polyphyletic, with golden moles and tenrecs placed in their own order (Afrosoricida) in the superordinal group Afrotheria. Studies based on nuclear genes support the monophyly of the remaining lipotyphlans (=Eulipotyphla) whereas mitochondrial genome studies dissociate hedgehogs from moles and place the former as the first offshoot on the placental tree. One shortcoming of previous molecular studies investigating lipotyphlan relationships is limited taxonomic sampling. Here, we evaluate lipotyphlan relationships using the largest and taxonomically most diverse data set yet assembled for Lipotyphla. Our results provide convincing support for both lipotyphlan diphyly and the monophyly of Eulipotyphla. More surprisingly, we find strong evidence for a sister-group relationship between shrews and hedgehogs to the exclusion of moles.

  17. Ticks parasitizing bats (Mammalia: Chiroptera) in the Caatinga Biome, Brazil.

    PubMed

    Luz, Hermes Ribeiro; Muñoz-Leal, Sebastián; Almeida, Juliana Cardoso de; Faccini, João Luiz Horacio; Labruna, Marcelo Bahia

    2016-01-01

    In this paper, the authors report ticks parasitizing bats from the Serra das Almas Natural Reserve (RPPN) located in the municipality of Crateús, state of Ceará, in the semiarid Caatinga biome of northeastern Brazil. The study was carried out during nine nights in the dry season (July 2012) and 10 nights in the rainy season (February 2013). Only bats of the Phyllostomidae and Mormoopidae families were parasitized by ticks. The species Artibeus planirostris and Carolia perspicillata were the most parasitized. A total of 409 larvae were collected and classified into three genera: Antricola (n = 1), Nothoaspis (n = 1) and Ornithodoros (n = 407). Four species were morphologically identified as Nothoaspis amazoniensis, Ornithodoros cavernicolous, Ornithodoros fonsecai, Ornithodoros hasei, and Ornithodoros marinkellei. Ornithodoros hasei was the most common tick associated with bats in the current study. The present study expand the distributional ranges of at least three soft ticks into the Caatinga biome, and highlight an unexpected richness of argasid ticks inhabiting this arid ecosystem.

  18. Generic names of northern and southern fur seals (Mammalia: Otariidae)

    USGS Publications Warehouse

    Gardner, A.L.; Robbins, C.B.

    1998-01-01

    We have resolved a nomenclatural problem discovered during research on the northern fur seal that concerns the correct generic name for this taxon and for fur seals of the Southern Hemisphere. The unfortunate practice by some 19th century authors to use names in their Latinized form, but to date them from their first appearance as French common names led to the use of Arctocephalus for southern fur seals when the name correctly applies to the northern fur seal, known today as Callorhinus ursinus. However, Arctocephalus and Callorhinus are antedated by Otoes G. Fischer, 1817, which is the earliest available generic for the fur seal of the northern Pacific. The earliest available generic name for southern fur seals is Halarctus Gill, 1866. To avoid the confusion that would result from replacing the currently used generic names with those required by strict adherence to the Principle of Priority, we have petitioned the International Commission on Zoological nomenclature to preserve Arctocephalus and Callorhinus for the southern and northern fur seals, respectively.

  19. Comparison of mitochondrial genome sequences of pangolins (Mammalia, Pholidota).

    PubMed

    Hassanin, Alexandre; Hugot, Jean-Pierre; van Vuuren, Bettine Jansen

    2015-04-01

    The complete mitochondrial genome was sequenced for three species of pangolins, Manis javanica, Phataginus tricuspis, and Smutsia temminckii, and comparisons were made with two other species, Manis pentadactyla and Phataginus tetradactyla. The genome of Manidae contains the 37 genes found in a typical mammalian genome, and the structure of the control region is highly conserved among species. In Manis, the overall base composition differs from that found in African genera. Phylogenetic analyses support the monophyly of the genera Manis, Phataginus, and Smutsia, as well as the basal division between Maninae and Smutsiinae. Comparisons with GenBank sequences reveal that the reference genomes of M. pentadactyla and P. tetradactyla (accession numbers NC_016008 and NC_004027) were sequenced from misidentified taxa, and that a new species of tree pangolin should be described in Gabon.

  20. A reexamination of the Carnivora malleus (Mammalia, Placentalia).

    PubMed

    Wible, John R; Spaulding, Michelle

    2012-01-01

    Authoritative anatomical references depict domestic dogs and cats as having a malleus with a short rostral (anterior) process that is connected via a ligament to the ectotympanic of the auditory bulla. Similar mallei have been reported for representatives of each of the 15 extant families of Carnivora, the placental order containing dogs and cats. This morphology is in contrast to a malleus with a long rostral process anchored to the ectotympanic that is considered to be primitive for mammals. Our reexamination of extant carnivorans found representatives from 12 families that possess an elongate rostral process anchored to the ectotympanic. Consequently, the malleus also is a component of the bulla. In a subset of our carnivoran sample, we confirmed that the elongate rostral process on the ectotympanic is continuous with the rest of the malleus through a thin osseous lamina. This morphology is reconstructed as primitive for Carnivora. Prior inaccurate descriptions of the taxa in our sample having mallei continuous with the bulla were based on damaged mallei. In addition to coupling to the ectotympanic, the rostral process of the malleus was found to have a hook-like process that fits in a facet on the skull base in representatives from seven families (felids, nandiniids, viverrids, canids, ursids, procyonids, and mustelids); its occurrence in the remaining families could not be ascertained. This feature is named herein the mallear hook and is likewise reconstructed to be primitive for Carnivora. We also investigated mallei in one additional placental order reported to have mallei not connected to the ectotympanic, Pholidota (pangolins), the extant sister group of Carnivora. We found pholidotans to also have anchored mallei with long rostral processes, but lacking mallear hooks. In light of our results, other mammals previously reported to have short rostral processes should be reexamined.

  1. Characterization of paneth cells in alpacas (Vicugna pacos, Mammalia, Camelidae).

    PubMed

    Vásquez, María; Lira, Boris; Rodríguez, José; Falcón, Néstor; Ocampo, Jorge; Nishida, Fabián; Barbeito, Claudio; Zanuzzi, Carolina

    2016-08-01

    Paneth cells are secretory epithelial cells of the innate immune system of the intestine of several mammals, including alpacas. Little is known about the latter; thus, in the present study we described the morphology and histochemical characteristics of Paneth cells in healthy fetuses, and young and adult alpacas. For this purpose, samples of duodenum, jejunum and ileum were taken from 6 fetuses at different days of pregnancy (between days 221-330), 66 offsprings (between 0 and 45-days-old) and 5 adult alpacas (>2-years-old). Samples were fixed in 10% buffered formalin and processed for histological and morphometrical analysis using HE and Masson Trichomićs technique. Immunohistochemistry was used to identify Paneth cells using anti-lysozyme antibody. In addition, the lectinhistochemichal binding-pattern of Paneth celĺs granules was evaluated. Lyzozyme was immunohistochemically detected in the granules of Paneth cells from day 283 of pregnancy in all the small intestinal sections of the studied fetuses. In newborn alpacas Paneth cells were initially found in the duodenum, but the following days (days 18-21 after birth) they were also found in the ileum. Their size gradually increased after birth, but then no significant differences were found. In adult alpacas the number was lower than offsprings. We suggest that Paneth cells early differentiate in the small intestine of alpacas, and the increase in their number during the first two weeks of life strongly support their possible involvement in the intestinal defensive functions against the enteric diseases that occur during the lactancy stage.

  2. Helminths of three species of opossums (Mammalia, Didelphidae) from Mexico

    PubMed Central

    Acosta-Virgen, Karla; López-Caballero, Jorge; García-Prieto, Luis; Mata-López, Rosario

    2015-01-01

    Abstract From August 2011 to November 2013, 68 opossums (8 Didelphis sp., 40 Didelphis virginiana, 15 Didelphis marsupialis, and 5 Philander opossum) were collected in 18 localities from 12 Mexican states. A total of 12,188 helminths representing 21 taxa were identified (6 trematodes, 2 cestodes, 3 acanthocephalans and 10 nematodes). Sixty-six new locality records, 9 new host records, and one species, the trematode Brachylaima didelphus, is added to the composition of the helminth fauna of the opossums in Mexico. These data, in conjunction with previous records, bring the number of taxa parasitizing the Mexican terrestrial marsupials to 41. Among these species, we recognized a group of helminths typical of didelphids in other parts of the Americas. This group is constituted by the trematode Rhopalias coronatus, the acanthocephalan Oligacanthorhynchus microcephalus and the nematodes Cruzia tentaculata, Gnathostoma turgidum, and Turgida turgida. In general, the helminth fauna of each didelphid species showed a stable taxonomic composition with respect to previously sampled sites. This situation suggests that the rate of accumulation of helminth species in the inventory of these 3 species of terrestrial marsupials in the Neotropical portion of Mexico is decreasing; however, new samplings in the Nearctic portion of this country will probably increase the richness of the helminthological inventory of this group of mammals. PMID:26257556

  3. Enamel microstructure in Lemuridae (Mammalia, Primates): assessment of variability.

    PubMed

    Maas, M C

    1994-10-01

    This study describes the molar enamel microstructure of seven lemurid primates: Hapalemur griseus, Varecia variegata, Lemur catta, Lemur macaco, Lemur fulvus rufus, Lemur fulvus fulvus, and Lemur fulvus albifrons. Contrary to earlier accounts, which reported little or no prism decussation in lemurid enamel, both Lemur and Varecia molars contain a prominent inner layer of decussating prisms (Hunter-Schreger bands), in addition to an outer radial prism layer, and a thin, nonprismatic enamel surface layer. In contrast, Hapalemur enamel consists entirely of radial and, near the surface, nonprismatic enamel. In addition, for all species, prism packing patterns differ according to depth from the tooth surface, and for all species but Varecia (which also has the thinnest enamel of any lemurid), average prism area increases from the enamel-dentine junction to the surface; this may be a developmental solution to the problem of accommodating a larger outer surface area with enamel deposited from a fixed number of cells. Finally, contradicting some previous reports, Pattern 1 prisms predominate only in the most superficial prismatic enamel. In the deeper enamel, prism cross-sections include both closed (Pattern 1) and arc-shaped (Pattern 2 or, most commonly, Pattern 3). This sequence of depth-related pattern change is repeated in all taxa. It should also be emphasized that all taxa can exhibit all three prism patterns in their mature enamel. The high degree of quantitative and qualitative variation in prism size, shape, and packing suggests that these features should be used cautiously in phylogenetic studies. Hapalemur is distinguished from the other lemurids by unique, medially constricted or rectangular prism cross-sections at an intermediate depth and the absence of prism decussation, but, without further assessment of character polarity, these differences do not clarify lemurid phylogenetic relations. Some characters of enamel microstructure may represent synapomorphies of Lemuridae, or of clades within Lemuridae, but homoplasty is likely to be common. Homoplasy of enamel characters may reflect functional constraints.

  4. A Reexamination of the Carnivora Malleus (Mammalia, Placentalia)

    PubMed Central

    Wible, John R.; Spaulding, Michelle

    2012-01-01

    Authoritative anatomical references depict domestic dogs and cats as having a malleus with a short rostral (anterior) process that is connected via a ligament to the ectotympanic of the auditory bulla. Similar mallei have been reported for representatives of each of the 15 extant families of Carnivora, the placental order containing dogs and cats. This morphology is in contrast to a malleus with a long rostral process anchored to the ectotympanic that is considered to be primitive for mammals. Our reexamination of extant carnivorans found representatives from 12 families that possess an elongate rostral process anchored to the ectotympanic. Consequently, the malleus also is a component of the bulla. In a subset of our carnivoran sample, we confirmed that the elongate rostral process on the ectotympanic is continuous with the rest of the malleus through a thin osseous lamina. This morphology is reconstructed as primitive for Carnivora. Prior inaccurate descriptions of the taxa in our sample having mallei continuous with the bulla were based on damaged mallei. In addition to coupling to the ectotympanic, the rostral process of the malleus was found to have a hook-like process that fits in a facet on the skull base in representatives from seven families (felids, nandiniids, viverrids, canids, ursids, procyonids, and mustelids); its occurrence in the remaining families could not be ascertained. This feature is named herein the mallear hook and is likewise reconstructed to be primitive for Carnivora. We also investigated mallei in one additional placental order reported to have mallei not connected to the ectotympanic, Pholidota (pangolins), the extant sister group of Carnivora. We found pholidotans to also have anchored mallei with long rostral processes, but lacking mallear hooks. In light of our results, other mammals previously reported to have short rostral processes should be reexamined. PMID:23209753

  5. Breaking constraint: axial patterning in Trichechus (Mammalia: Sirenia).

    PubMed

    Buchholtz, Emily A; Wayrynen, Kaisa L; Lin, Iris W

    2014-01-01

    Meristic variation is often limited in serially homologous systems with high internal differentiation and high developmental modularity. The mammalian neck, an extreme example, has a fixed (at seven) count of diversely specialized segments. Imposition of the mammalian cervical constraint has been tentatively linked to the origin of the diaphragm, which is muscularized by cells that migrate from cervical somites during development. With six cervical vertebrae, the genus Trichechus (manatee) has apparently broken this constraint, although the mechanism of constraint escape is unknown. Hypotheses for the developmental origin of Trichechus cervical morphology include cervical rib 7 repatterning, a primaxial/abaxial patterning shift, and local homeosis at the cervical/thoracic boundary. We tested predictions of these hypotheses by documenting vertebral morphology, axial ossification patterns, regionalization of the postcranial skeleton, and the relationship of thoracic ribs to sternal subunits in a large data set of fetal and adult Trichechus and Dugong specimens. These observations forced rejection of all three hypotheses. We propose alternatively that a global slowing of the rate of somitogenesis reduced somite count and disrupted alignment of Hox-generated anatomical markers relative to somite (and vertebral) boundaries throughout the Trichechus column. This hypothesis is consistent with observations of the full range of traditional cervical morphologies in the six cervical vertebrae, conserved postcranial proportions, and column-wide reduction in count relative to its sister taxon, Dugong. It also suggests that the origin of the mammalian cervical constraint lies in patterning, not in count, and that Trichechus and the tree sloths have broken the constraint using different developmental mechanisms.

  6. Vertebral anomaly in fossil sea cows (Mammalia, Sirenia).

    PubMed

    Voss, Manja; Asbach, Patrick; Hilger, André

    2011-06-01

    Four incompletely preserved caudal vertebrae lacking the neural arches of two fossil sirenian individuals of Halitherium schinzii (Oligocene) from the Rhine area in Germany and northern Belgium reveal osteological alterations. The caudal vertebrae possess a transverse process with growth retardation. This asymmetry indicates that the affected transverse processes are less developed than their counterparts and, consequently, deviate from the norm. Computed tomography (CT) scans reveal osteosclerotic patterns, a morphological feature that characterizes sea cows and supports the nonpathological state of the vertebrae. Additionally, no indications of vertebral fractures or any other occurrences due to external factors are present. This is the oldest documentation of such an anomaly in any sirenian and is interpreted here as hypoplasia, the underdevelopment of an organ or parts of it that might cause a functional deficiency.

  7. Ticks infesting bats (Mammalia: Chiroptera) in the Brazilian Pantanal.

    PubMed

    Muñoz-Leal, Sebastián; Eriksson, Alan; Santos, Carolina Ferreira; Fischer, Erich; de Almeida, Juliana Cardoso; Luz, Hermes R; Labruna, Marcelo B

    2016-05-01

    Ticks associated with bats have been poorly documented in the Neotropical Zoogeographical Region. In this study, a total of 1028 bats were sampled for tick infestations in the southern portion of the Brazilian Pantanal. A total of 368 ticks, morphologically identified as Ornithodoros hasei (n = 364) and O. mimon (n = 4), were collected from the following bat species: Artibeus planirostris, Platyrrhinus lineatus, Phyllostomus hastatus, Mimon crenulatum and Noctilio albiventris. Morphological identification of O. hasei was confirmed by molecular analysis. Regarding the most abundant bat species, only 40 (6.2%) out of 650 A. planirostris were infested by O. hasei, with a mean intensity of 7.2 ticks per infested bat, or a mean abundance of 0.44 ticks per sampled bat. Noteworthy, one single P. hastatus was infested by 55 O. hasei larvae, in contrast to the 2.5-7.2 range of mean intensity values for the whole study. As a complement to the present study, a total of 8 museum bat specimens (6 Noctilio albiventris and 2 N. leporinus), collected in the northern region of Pantanal, were examined for tick infestations. These bats contained 176 ticks, which were all morphologically identified as O. hasei larvae. Mean intensity of infestation was 22, with a range of 1-46 ticks per infested bat. Our results suggest that A. planirostris might play an important role in the natural life cycle of O. hasei in the Pantanal.

  8. Sensory Hairs in the Bowhead Whale, Balaena mysticetus (Cetacea, Mammalia).

    PubMed

    Drake, Summer E; Crish, Samuel D; George, John C; Stimmelmayr, Raphaella; Thewissen, J G M

    2015-07-01

    We studied the histology and morphometrics of the hairs of bowhead whales (Balaena mysticetus). These whales are hairless except for two patches of more than 300 hairs on the rostral tip of the lower lip and chin, the rostral tip of the upper lip, and a bilateral row of approximately ten hairs caudal to the blowhole. Histological data indicate that hairs in all three of these areas are vibrissae: they show an outermost connective tissue capsule, a circumferential blood sinus system surrounding the hair shaft, and dense innervation to the follicle. Morphometric data were collected on hair diameters, epidermal recess diameters, hair follicle length, and external hair lengths. The main difference between the hairs in the different regions is that blowhole hairs have larger diameters than the hairs in the chin and rostrum regions. We speculate that the hair shaft thickness patterns in bowheads reflect functional specializations.

  9. ASTROMOL: moles de ciencia y divulgación

    NASA Astrophysics Data System (ADS)

    Ruiz-Zelmanovitch, N.; Castellanos, M.

    2015-05-01

    ASTROMOL is the nickname of the project ``Consolider-Ingenio 2010 ASTROMOL, Molecular Astrophysics: The Herschel and ALMA era'', a program that comes to an end soon and in which we have obtained important results and both scientific and technological advances. In this presentation we will discuss these results and the tools we have used to spread them to the society.

  10. Reducing Carbon Dioxide Emissions: Using the Mole Concept.

    ERIC Educational Resources Information Center

    Myers, Alan

    2002-01-01

    Provides an application of quantitative chemistry concepts in the context of motor vehicle emissions. Shows how carbon dioxide emissions from cars may be reduced by up to 25% by reducing motorway speeds from 70-75 mph to 60 mph. (Author/MM)

  11. Partial hydatidiform mole and coexisting viable twin pregnancy.

    PubMed

    Tay, Ee Tein

    2013-12-01

    Twin partial hydatidiform molar pregnancy with a viable fetus is an uncommon occurrence. Presentations of molar pregnancies include vaginal bleeding, unusually elevated β-human chorionic gonadotropin level, and preeclampsia. Previous descriptions of twin molar and fetus pregnancies in the literature have been described in the outpatient obstetric setting. We present a case of partial molar pregnancy with a viable fetus detected with emergency ultrasound in a pediatric emergency department.

  12. A Mole's Eye View: Marcellus as Mosaic by Rachel Sager

    NASA Astrophysics Data System (ADS)

    Sager, R.

    2013-12-01

    I am an artist living and working in the energy vortex of Southwestern Pennsylvania and am watching great upheaval, both good and bad, happen to my land and its citizens due to the phenomenon caused by our particular geologic formation; the Marcellus Shale. My work embraces the earth itself through the medium of mosaic, and I have found it to be a great communicator to many groups of people: landowners, gas industry workers, environmentalists. I tell the story of how I came to be so dependent on my native stone, coming from a long line of coal miners and farmers who taught me to be aware of what lies beneath my feet. With my stone hammer, I chop up shale, sandstone, limestone, and coal, transforming it into tiny, expressive pieces that tell stories and help people to grasp geologic concepts that can otherwise be overwhelming and mysterious. I address the industry itself by representing the controversial enterprise of fracking, but also delve intimately into building relationships with the stone that I gather, wash, categorize, cut, and lay into mortar. By depicting these layers of earth, I am building touchable, organic images of geologic time that are highly accessible to the human brain and sensibility. There is something personal and immediate about standing in front of one of these mosaics, being able to touch it that gives the viewer power over an idea that often leaves them feeling in the dark. As a classically trained mosaic artist, I bring back the skills, culture, and tradition of a Euro-centered art form and weave it into my North American geology. Through a highly detailed and dynamic PowerPoint presentation of my work, I help people to see the earth beneath their feet with new eyes. Rachel Sager, artist www.rachelsagermosaics.com Contemporary Art in a Geologic Medium: Rachel Sager Mosaics

  13. Molecular estimation of eulipotyphlan divergence times and the evolution of "Insectivora".

    PubMed

    Douady, Christophe J; Douzery, Emmanuel J P

    2003-08-01

    "Insectivores" are one of the key groups in understanding mammalian origins. For years, systematics of "Lipotyphla" taxa remained extremely unstable and challenged. Today, with the application of molecular techniques, "Lipotyphla" appears to be a paraphyletic assemblage that encompasses hedgehogs, shrews, and moles (i.e., Eulipotyphla-a member of Laurasiatheria), and golden moles and tenrecs (i.e., Afrosoricida-a member of Afrotheria). Based on nuclear genes and on this well-established phylogenetic framework, we estimated Bayesian relaxed molecular clock divergence times among major lineages of "Lipotyphla." Crown placental mammals are shown to diversify 102+/-6 million years ago (Mya; mean+/-one standard-deviation), followed by Boreoeutheria (94+/-6 Mya), Laurasiatheria (85+/-5 Mya), and Eulipotyphla (73+/-5), with moles separating from hedgehogs+shrews just at the K/T boundary (65+/-5 Mya). During the Early and Middle Eocene, all extant eulipotyphlan subfamilies originated: Uropsilinae (52+/-5 Mya), and Desmaninae, Talpinae, Erinaceinae, Hylomyinae, Soricinae, and Crocidurinae (38-42+/-5 Mya). Afrosoricida separated from Macroscelidae 69+/-5 Mya, golden moles from tenrecs 63+/-5 Mya, and the diversification within tenrecs occurred 43+/-5 Mya. Divergence times are shown to be in reasonably good agreement with the fossil record of eulipotyphlans, but not with the one of afrosoricid "insectivores." Eulipotyphlans diversification might have been sculpted by variations in paleoclimates of the cenozoic era.

  14. Patterns of ossification in southern versus northern placental mammals.

    PubMed

    Hautier, Lionel; Bennett, Nigel C; Viljoen, Hermien; Howard, Lauren; Milinkovitch, Michel C; Tzika, Athanasia C; Goswami, Anjali; Asher, Robert J

    2013-07-01

    Consensus on placental mammal phylogeny is fairly recent compared to that for vertebrates as a whole. A stable phylogenetic hypothesis enables investigation into the possibility that placental clades differ from one another in terms of their development. Here, we focus on the sequence of skeletal ossification as a possible source of developmental distinctiveness in "northern" (Laurasiatheria and Euarchontoglires) versus "southern" (Afrotheria and Xenarthra) placental clades. We contribute data on cranial and postcranial ossification events during growth in Afrotheria, including elephants, hyraxes, golden moles, tenrecs, sengis, and aardvarks. We use three different techniques to quantify sequence heterochrony: continuous method, sequence-ANOVA (analysis of variance) and event-paring/Parsimov. We show that afrotherians significantly differ from other placentals by an early ossification of the orbitosphenoid and caudal vertebrae. Our analysis also suggests that both southern placental groups show a greater degree of developmental variability; however, they rarely seem to vary in the same direction, especially regarding the shifts that differ statistically. The latter observation is inconsistent with the Atlantogenata hypothesis in which afrotherians are considered as the sister clade of xenarthrans. Interestingly, ancestral nodes for Laurasiatheria and Euarchontoglires show very similar trends and our results suggest that developmental homogeneity in some ossification sequences may be restricted to northern placental mammals (Boreoeutheria).

  15. The evolution of reproduction-related NLRP genes.

    PubMed

    Duéñez-Guzmán, Edgar A; Haig, David

    2014-04-01

    NLRP proteins are important components of inflammasomes with a major role in innate immunity. A subset of NLRP genes, with unknown functions, are expressed in oocytes and early embryos. Mutations of Nlrp5 in mice are associated with maternal-effect embryonic lethality and mutations of NLRP7 in women are associated with conception of biparental complete hydatidiform moles (biCHMs), suggesting perturbed processes of genomic imprinting. Recessive mutations on NLRP2/7 in humans are associated with reproductive disorders and appear to be induced by a demethylation of the maternal pronucleus. In this study, we find that radiation of NLRP genes occurred before the common ancestor of Afrotheria and Boreoeutheria, with the clade of oocyte-expressed genes originating before the divergence of marsupial and eutherian mammals. There have been multiple independent duplications of NLRP2 genes one of which produced the NLRP7 gene associated with biCHMs.

  16. Ocepeia (Middle Paleocene of Morocco): the oldest skull of an afrotherian mammal.

    PubMed

    Gheerbrant, Emmanuel; Amaghzaz, Mbarek; Bouya, Baadi; Goussard, Florent; Letenneur, Charlène

    2014-01-01

    While key early(iest) fossils were recently discovered for several crown afrotherian mammal orders, basal afrotherians, e.g., early Cenozoic species that comprise sister taxa to Paenungulata, Afroinsectiphilia or Afrotheria, are nearly unknown, especially in Africa. Possible stem condylarth-like relatives of the Paenungulata (hyraxes, sea-cows, elephants) include only Abdounodus hamdii and Ocepeia daouiensis from the Selandian of Ouled Abdoun Basin, Morocco, both previously only documented by lower teeth. Here, we describe new fossils of Ocepeia, including O.grandis n. sp., and a sub-complete skull of O. daouiensis, the first known before the Eocene for African placentals. O.daouiensis skull displays a remarkable mosaic of autapomophic, ungulate-like and generalized eutherian-like characters. Autapomorphies include striking anthropoid-like characters of the rostrum and dentition. Besides having a basically eutherian-like skull construction, Ocepeia daouiensis is characterized by ungulate-like, and especially paenungulate-like characters of skull and dentition (e.g., selenodonty). However, some plesiomorphies such as absence of hypocone exclude Ocepeia from crown Paenungulata. Such a combination of plesiomorphic and derived characters best fits with a stem position of Ocepeia relative to Paenungulata. In our cladistic analyses Ocepeia is included in Afrotheria, but its shared derived characters with paenungulates are not optimized as exclusive synapomorphies. Rather, within Afrotheria Ocepeia is reconstructed as more closely related to insectivore-like afroinsectiphilians (i.e., aardvarks, sengis, tenrecs, and golden moles) than to paenungulates. This results from conflict with undetected convergences of Paenungulata and Perissodactyla in our cladistic analysis, such as the shared bilophodonty. The selenodont pattern best supports the stem paenungulate position of Ocepeia; that, however, needs further support. The remarkable character mosaic of Ocepeia makes it the

  17. Ocepeia (Middle Paleocene of Morocco): The Oldest Skull of an Afrotherian Mammal

    PubMed Central

    Gheerbrant, Emmanuel; Amaghzaz, Mbarek; Bouya, Baadi; Goussard, Florent; Letenneur, Charlène

    2014-01-01

    While key early(iest) fossils were recently discovered for several crown afrotherian mammal orders, basal afrotherians, e.g., early Cenozoic species that comprise sister taxa to Paenungulata, Afroinsectiphilia or Afrotheria, are nearly unknown, especially in Africa. Possible stem condylarth-like relatives of the Paenungulata (hyraxes, sea-cows, elephants) include only Abdounodus hamdii and Ocepeia daouiensis from the Selandian of Ouled Abdoun Basin, Morocco, both previously only documented by lower teeth. Here, we describe new fossils of Ocepeia, including O.grandis n. sp., and a sub-complete skull of O. daouiensis, the first known before the Eocene for African placentals. O.daouiensis skull displays a remarkable mosaic of autapomophic, ungulate-like and generalized eutherian-like characters. Autapomorphies include striking anthropoid-like characters of the rostrum and dentition. Besides having a basically eutherian-like skull construction, Ocepeia daouiensis is characterized by ungulate-like, and especially paenungulate-like characters of skull and dentition (e.g., selenodonty). However, some plesiomorphies such as absence of hypocone exclude Ocepeia from crown Paenungulata. Such a combination of plesiomorphic and derived characters best fits with a stem position of Ocepeia relative to Paenungulata. In our cladistic analyses Ocepeia is included in Afrotheria, but its shared derived characters with paenungulates are not optimized as exclusive synapomorphies. Rather, within Afrotheria Ocepeia is reconstructed as more closely related to insectivore-like afroinsectiphilians (i.e., aardvarks, sengis, tenrecs, and golden moles) than to paenungulates. This results from conflict with undetected convergences of Paenungulata and Perissodactyla in our cladistic analysis, such as the shared bilophodonty. The selenodont pattern best supports the stem paenungulate position of Ocepeia; that, however, needs further support. The remarkable character mosaic of Ocepeia makes it the

  18. Deux nouvelles espèces de Suini (Mammalia, Suidae) du continent Africain (Éthiopie; Tchad)Two new Suin species (Mammalia, Suidae) from Africa (Chad, Ethiopia)

    NASA Astrophysics Data System (ADS)

    Brunet, Michel; White, Tim D.

    2001-01-01

    Two new small Suines, Kolpochoerus deheinzelini sp. nov. and Kolpochoerus cookei sp. nov., are described. The first one represents the earliest appearance of the genus and the earliest African Suine. K. deheinzelini n. sp. is the ancestor of K. afarensis, previously considered as an Eurasiatic migrant in the Middle Pliocene of Africa (Pickford, 1994). The second one is the smallest species of the genus.

  19. Dental eruption in afrotherian mammals

    PubMed Central

    Asher, Robert J; Lehmann, Thomas

    2008-01-01

    Background Afrotheria comprises a newly recognized clade of mammals with strong molecular evidence for its monophyly. In contrast, morphological data uniting its diverse constituents, including elephants, sea cows, hyraxes, aardvarks, sengis, tenrecs and golden moles, have been difficult to identify. Here, we suggest relatively late eruption of the permanent dentition as a shared characteristic of afrotherian mammals. This characteristic and other features (such as vertebral anomalies and testicondy) recall the phenotype of a human genetic pathology (cleidocranial dysplasia), correlations with which have not been explored previously in the context of character evolution within the recently established phylogeny of living mammalian clades. Results Although data on the absolute timing of eruption in sengis, golden moles and tenrecs are still unknown, craniometric comparisons for ontogenetic series of these taxa show that considerable skull growth takes place prior to the complete eruption of the permanent cheek teeth. Specimens showing less than half (sengis, golden moles) or two-thirds (tenrecs, hyraxes) of their permanent cheek teeth reach or exceed the median jaw length of conspecifics with a complete dentition. With few exceptions, afrotherians are closer to median adult jaw length with fewer erupted, permanent cheek teeth than comparable stages of non-afrotherians. Manatees (but not dugongs), elephants and hyraxes with known age data show eruption of permanent teeth late in ontogeny relative to other mammals. While the occurrence of delayed eruption, vertebral anomalies and other potential afrotherian synapomorphies resemble some symptoms of a human genetic pathology, these characteristics do not appear to covary significantly among mammalian clades. Conclusion Morphological characteristics shared by such physically disparate animals such as elephants and golden moles are not easy to recognize, but are now known to include late eruption of permanent teeth, in

  20. A new species of mole cricket (Orthoptera: Gryllotalpidae: Gryllotalpinae) from Bukit Fraser, Malay Peninsula, with taxa notes on another similar mole cricket.

    PubMed

    Tan, Ming Kai; Kamaruddin, Khairul Nizam

    2013-01-01

    One new species of Gryllotalpa from Bukit Fraser, Pahang of Malay Peninsula is described: Gryllotalpafraser sp. n. Pho tographs of Gryllotalpa hirsuta Burmeister, 1838 were examined and some remarks are made here, including a compari son with Gryllotalpafraser sp. n. and Gyllotalpa nymphicus Tan, 2012.

  1. [Genetic diversity of Chionomys genus (Mammalia, Arvicolinae) and comparative phylogeography of snow voles].

    PubMed

    Bannikova, A A; Sizhazheva, A M; Malikova, V G; Golenishchev, F N; Dzuev, R I

    2013-05-01

    In the present study, the genetic polymorphism of the Chionomys genus was examined based on the sequencing of the mitochondrial cytb gene and two nuclear exons, including CHR exon 10 and BRCA1 exon 11. The distinct subdivision of the genus of snow voles into five lineages, including Ch. nivalis, Ch. gud, Ch. roberti, and Ch. aff. nivalis from Turkey, as well as Ch. aff. gud from Turkey, was demonstrated. The branching order in the trees constructed based on the data for different genes was ambiguous, which was probably the consequence of recent and rapid radiation of the major lineages from a common ancestor. However, the data of the mitochondrial and nuclear gene analyses definitely indicated that the genetic and taxonomic diversity of the Chionomys genus was higher than it was expected before. The genetic divergence of some populations was so deep that they probably deserved the statuses of independent species. Despite that the range of the European snow vole Ch. nivalis is larger and more fragmented than the Gudaur vole Ch, gud, the latter species with its relatively small range, which is limited to the Caucasian and Pontic Mountains, was characterized by a similarly expressed phylogenetic structure. At the same time, Robert's vole Ch. roberti was less structured genetically than the first two species. The data obtained supported the Near Eastern, rather than the European origin of the Chionomys genus.

  2. Revision of the Wind River faunas, early Eocene of central Wyoming. X - Bunophorus (Mammalia, Artiodactyla)

    NASA Technical Reports Server (NTRS)

    Stucky, Richard K.; Krishtalka, Leonard

    1990-01-01

    Research on the holotypes and large collections of the species of Wasatchia and Bunophorus is reviewed. It is concluded that Bunophorus is a senior synonym of Wasatchia and includes six valid species, namely, B. etsagicus, B. grangeri, B. pattersoni, B. macropternus, B. sinclairi, and B. robustus. B. sinclairi includes two penecontemporaneous geographic variants: B.s. sinclairi from the Wind River, Piceance and Green River basins, and B.s. robinsoni, n. ssp., from the Huerfano Basin.

  3. Pliocene Carnivora (Mammalia) from the Hadar Formation at Dikika, Lower Awash Valley, Ethiopia

    NASA Astrophysics Data System (ADS)

    Geraads, Denis; Alemseged, Zeresenay; Bobe, René; Reed, Denné

    2015-07-01

    We report here on further study of the Carnivora collected by the Dikika Research Project at Dikika, in the Hadar Formation south of the type locality since 2000. The Canidae and the otter Enhydriodon have been described elsewhere, so we focus here on the other Mustelidae and on the Felidae and Hyaenidae. All Hyaenidae are referred to Crocuta, but differences in size and tooth proportions suggest two species that might belong to distinct lineages. An associated set of upper and lower teeth is made the type of a new species of Lutra that must be close to the divergence of Lutra palaeindica, Lutra lutra, and Hydrictis maculicollis. Sample size is still small, but the Dikika assemblage differs from others of similar age in the abundance of hyenas relative to felids.

  4. Comparative Morphology of Premolar Foramen in Lagomorphs (Mammalia: Glires) and Its Functional and Phylogenetic Implications

    PubMed Central

    Fostowicz-Frelik, Łucja; Meng, Jin

    2013-01-01

    Lagomorphs (a group that consists of pikas, hares, rabbits and allies) are notable for their conservative morphology retained for most of their over 50 million years evolutionary history. On the other hand, their remarkable morphological uniformity partly stems from a considerable number of homoplasies in cranial and dental structures that hamper phylogenetic analyses. The premolar foramen, an opening in the palate of lagomorphs, has been characterized as an important synapomorphy of one clade, Ochotonidae (pikas). Within Lagomorpha, however, its phylogenetic distribution is much wider, the foramen being present not only in all ochotonids but also in leporids and stem taxa; its morphology and incidence also varies considerably across the order, even intraspecifically. In this study, we provide a broad survey of the taxonomic distribution of the premolar foramen in extant and fossil Lagomorpha and describe in detail the morphological variation of this character within the group. Micro-computed tomography was used to examine the hard palate and infraorbital groove morphology in Poelagus (Leporidae) and Ochotona. Scans revealed the course and contacts of the canal behind the premolar foramen and structural differences between the two crown clades. We propose that the premolar foramen has evolved independently in several lineages of Lagomorpha, and we discuss development and function of this foramen in the lagomorph skull. This study shows the importance of comprehensive studies on phylogenetically informative non-dental characters in Lagomorpha. PMID:24278178

  5. Mitochondrial DNA differentiation among geographical populations of Pronolagus rupestris, Smith's red rock rabbit (Mammalia: Lagomorpha).

    PubMed

    Matthee, C A; Robinson, T J

    1996-05-01

    Geographical genetic population structure was determined for an endemic African leporid, Smith's red rock rabbit, Pronolagus rupestris. Restriction fragment length polymorphism analysis of mitochondrial DNA from 55 specimens revealed 32 distinct material lineages for the population sampled. The data show two major genetic assemblages separated by a mean sequence divergence of 7.94 per cent (+/- 1.40 per cent) and provide little support for the continued recognition of most of the described subspecies. The south-eastern assemblage is confined to the mountain ranges comprising the Great Escarpment of South Africa, while the north-western assemblage is not so tightly constrained. With the possible exception of elevation, no readily apparent ecological or topographical barrier could be identified which delimits the two mitochondrial clades. The sequence divergence separating the south-eastern and north western P. rupestris clades is high, and approximates the interspecific sequence divergences detected between P. rupestris and other Pronolagus species. The two P. rupestris clades are parapatric for part of their distribution, and the absence of shared mtDNA lineages is consistent with the hypothesis that the two populations are reproductively isolated from each other. We provisionally interpret this to reflect the presence of two hitherto undetected biological species in what has conventionally been recognized as a single taxon, P. rupestris.

  6. The evolution of orbit orientation and encephalization in the Carnivora (Mammalia)

    PubMed Central

    Finarelli, John A; Goswami, Anjali

    2009-01-01

    Evolutionary change in encephalization within and across mammalian clades is well-studied, yet relatively few comparative analyses attempt to quantify the impact of evolutionary change in relative brain size on cranial morphology. Because of the proximity of the braincase to the orbits, and the inter-relationships among ecology, sensory systems and neuroanatomy, a relationship has been hypothesized between orbit orientation and encephalization for mammals. Here, we tested this hypothesis in 68 fossil and living species of the mammalian order Carnivora, comparing orbit orientation angles (convergence and frontation) to skull length and encephalization. No significant correlations were observed between skull length and orbit orientation when all taxa were analysed. Significant correlations were observed between encephalization and orbit orientation; however, these were restricted to the families Felidae and Canidae. Encephalization is positively correlated with frontation in both families and negatively correlated with convergence in canids. These results indicate that no universal relationship exists between encephalization and orbit orientation for Carnivora. Braincase expansion impacts orbit orientation in specific carnivoran clades, the nature of which is idiosyncratic to the clade itself. PMID:19438762

  7. New craniodental material of Pronothodectes gaoi Fox (Mammalia, "Plesiadapiformes") and relationships among members of Plesiadapidae.

    PubMed

    Boyer, Doug M; Scott, Craig S; Fox, Richard C

    2012-04-01

    Plesiadapidae are a family of Paleogene mammals thought to have phylogenetic affinities with modern Primates. We describe previously unpublished dentitions and the first skull and isolated petrosals of the plesiadapid Pronothodectes gaoi, collected from middle Tiffanian localities of the Paskapoo Formation in Alberta. Other species of Pronothodectes, traditionally considered the most basal members of the Plesiadapidae, occur at earlier, Torrejonian horizons in Montana, Wyoming, and Alberta. Classification of P. gaoi as a species of Pronothodectes has proved controversial; accordingly, we use the newly available samples and the more extensively preserved specimens to re-evaluate the generic affinities of this species. Included in our study are comparisons with craniodental material known for other plesiadapids and plesiadapiforms. Cladistic analysis of craniodental characters is used to assess the hypothesis that P. gaoi and other species in this genus are basal members of the Plesiadapidae. The new dental evidence confirms that P. gaoi lacks derived character states of other plesiadapids except for a variably present fissuring of the m3 hypoconulid. Moreover, several aspects of the cranium seem to be more primitive in P. gaoi (i.e., more like nonplesiadapid plesiadapiforms) than in later occurring plesiadapids, such as Plesiadapis tricuspidens and Plesiadapis cookei. Cladistic analysis of craniodental morphology supports a basal position of P. gaoi among species of Plesiadapidae, with the exception of other species of Pronothodectes. The basicranium of P. gaoi preserves a laterally placed bony canal for the internal carotid neurovascular system, suggesting that this was the ancestral condition for the family.

  8. Reproductive anatomy of the female Amazonian manatee Trichechus inunguis Natterer, 1883 (Mammalia: Sirenia).

    PubMed

    Rodrigues, Fernanda Rosa; Da Silva, Vera Maria Ferreira; Barcellos, José Fernando Marques; Lazzarini, Stella Maris

    2008-05-01

    The Amazonian manatee (Trichechus inunguis) is uniparous and has a slow reproduction cycle due to a long gestation period and long interval between births. Even though protected by law, hunting remains one of the main causes hindering the natural population growth of this species in the wild. The histology and reproductive anatomy provide information on the history and reproductive status of the female and offer a tool for the conservation of the species. The present study describes the anatomy of the female reproductive tract in T. inunguis. It is based on materials from three reproductive tracts fixed in 10% buffered formalin. The ovaries, uterine tubes, uterus, vagina, and external genitalia are described. The hymen presents two tiny openings separated by a segment that, upon rupturing during the first copulation, should make up a single vaginal opening. A still intact hymen and the absence of placental scars in the uterus were found in one specimen. Additionally, the presence of a hemorrhagic body and Graafian follicles on the right ovary were observed, as well as whitish scars and among them, possible corpora albicantia. These findings suggest that T. inunguis undergoes infertile estrus cycles before its first gestation. Macroscopically, counting of the whitish scars is hindered by the small diameter of these structures. It is not possible to differentiate between the scars resulting from ruptured (corpora albicantia) and nonruptured follicles (regressed corpora atretica). The presence of whitish scars on both ovaries of the same specimen suggests their bilateral function in T. inunguis.

  9. Predicting the potential distribution of Vexillata (Nematoda: Ornithostrongylidae) and its hosts (Mammalia: Rodentia) within America.

    PubMed

    Martínez-Salazar, E A; Escalante, T; Linaje, M; Falcón-Ordaz, J

    2013-12-01

    Species distribution modelling has been a powerful tool to explore the potential distribution of parasites in wildlife, being the basis of studies on biogeography. Vexillata spp. are intestinal nematodes found in several species of mammalian hosts, such as rodents (Geomyoidea) and hares (Leporidae) in the Nearctic and northern Neotropical regions. In the present study, we modelled the potential distribution of Vexillata spp. and their hosts, using exclusively species from the Geomyidae and Heteromyidae families, in order to identify their distributional patterns. Bioclimatic and topographic variables were used to identify and predict suitable habitats for Vexillata and its hosts. Using these models, we identified that temperature seasonality is a significant environmental factor that influences the distribution of the parasite genus and its host. In particular, the geographical distribution is estimated to be larger than that predicted for its hosts. This suggests that the nematode has the potential to extend its geographical range and also its spectrum of host species. Increasing sample size and geographical coverage will contribute to recommendations for conservation of this host-parasite system.

  10. The evolution of fossoriality and the adaptive role of horns in the Mylagaulidae (Mammalia: Rodentia)

    PubMed Central

    Hopkins, Samantha S.B

    2005-01-01

    Ceratogaulus, a member of the extinct fossorial rodent clade Mylagaulidae, is the only known rodent with horns and the smallest known horned mammal. The function of the large, dorsally projecting nasal horns on this burrowing animal has been the subject of wide speculation among palaeontologists; suggested uses range from sexual combat to burrowing. Mammals have evolved adaptations for digging repeatedly; horns and other cranial appendages have also evolved numerous times. These two adaptations co-occur in mammals extremely rarely: only two fossil genera (Ceratogaulus and the xenarthran Peltephilus) and no extant mammals are both horned and fossorial. Tracing the evolution of fossoriality in aplodontoid rodents (the larger clade to which Ceratogaulus belongs) reveals that Ceratogaulus descended from ancestors who dug by head-lifting. Whereas this suggests an obvious explanation for the horns of this rodent, evidence from functional morphology, anatomy, phylogeny and geologic context indicates that the horns in Ceratogaulus were used for defence, rather than digging, and evolved to offset increased predation costs associated with spending more time foraging above ground as body size increased. PMID:16087426

  11. Comparative morphology and evolution of the otic region in toothed whales (Cetacea, Mammalia).

    PubMed

    Oelschläger, H A

    1986-11-01

    The otic region in the skull of archeocetes and odontocetes is compared and interpreted with special emphasis on the morphology and suspension of the ear bones. In archeocetes, the periotic was obviously separate from the mastoid but still integrated within the skull via a long anterior and posterior process. The rotation of the cochlear part of the periotic was already obvious. The tympanic bone was attached to a decreasing number of neighboring elements, with the periotic becoming more and more important in the later archeocetes. The accessory air sacs of the tympanic cavity had invaded some of the adjacent skeletal elements and attained a moderate-to-remarkable extension. In the evolution of the odontocetes, the periotic and tympanic were successively uncoupled from the skull and combined to a new morphological and functional unit (tympanoperiotic complex). This uncoupling was mainly achieved by shortening the periotical processes and simultaneously extending the tympanic air sacs. For functional reasons, however, the periotic (posterior process) stayed in immediate contact with the mastoid, the latter remaining in the lateral wall of skull. In advanced marine dolphins, the bony sheaths of the accessory air sacs are largely reduced, presumably because of volume fluctuations in the tympanic cavity during diving. The perfect uncoupling of the ear bones from the skull obviously was an essential prerequisite for directional hearing, for effective ultrasound orientation and communication, and finally, for the striking development of the dolphin brain.

  12. Population structure of the gomphothere Stegomastodon waringi (Mammalia: Proboscidea: Gomphotheriidae) from the Pleistocene of Brazil.

    PubMed

    Mothé, Dimila; Avilla, Leonardo S; Winck, Gisele R

    2010-11-26

    The Quaternary fossil record of Águas de Araxá (QAA) is represented mainly by an accumulation of skeletal elements of several sizes, which are assigned to a population of Stegomastodon waringi. We analyzed 97 molars according to the wear stages of Simpson and Paula-Couto (1957), and developed a morphometric wear index. The population structure (proportion of immature, subadult, adult, mature adult and senile adult individuals) was identified, and these five age classes were compared to those of extant elephant populations and defined with social implications. The analysis made possible to establish that the population is largely composed of adults: 14.89% are immature individuals, 23.04% subadults, 27.65% adults, 17.21% mature adults and another 17.21% senile adults. Based on population structure, we do not discard the possibility that the fossil population was stable or in recovery, and/or was experiencing a high-predation period on younger individuals. The number of individuals composing the past population studied here could suggest that the occupied environment was open due to comparisons to populations of extant elephants. We consider this population as an aggregation of family units, which suggests a time of low environmental humidity. Based on literature and our findings, their extinction appears to be regional and probably related to a catastrophic event.

  13. Morphological variation in the ear region of pleistocene elephantimorpha (Mammalia, Proboscidea) from central Texas.

    PubMed

    Ekdale, Eric G

    2011-04-01

    A large sample of isolated elephantimorph petrosal bones was recovered from Pleistocene deposits in Friesenhahn Cave, Bexar County, Texas. Morphology of the middle and inner ear of the elephantimorphs is described and variation within the sample is identified. Observed variations occur in the stapedial ratio, morphology of the aquaeductus Fallopii, and connection of the crista interfenestralis to the tympanohyal on the posterior portion of the petrosal to form a foramen for passage of the stapedius muscle. The morphology of the aquaeductus Fallopii supports an ontogenetic explanation for some variation, and a sequence of ossification surrounding the aquaeductus Fallopii, from the anterior end of the canal to the posterior, is hypothesized. The stapedial ratio varies to a high degree across the sample, and such variation should be considered when the ratio is used in phylogenetic analyses. Within the inner ear, the absence of the secondary lamina suggests evolution of low-frequency hearing in extinct proboscideans, which is known for extant elephants. The morphology of the petrosals from Friesenhahn Cave is compared to published descriptions of the ear regions of other extinct proboscideans, and the distribution and evolution of morphologic characters are discussed. J. Morphol., 2011. © 2011 Wiley-Liss, Inc.

  14. Population structure of the gomphothere Stegomastodon waringi (Mammalia: Proboscidea: Gomphotheriidae) from the Pleistocene of Brazil.

    PubMed

    Mothé, Dimila; Avilla, Leonardo S; Winck, Gisele R

    2010-12-01

    The Quaternary fossil record of Águas de Araxá (Q AA) is represented mainly by an accumulation of skeletal elements of several sizes, which are assigned to a population of Stegomastodon waringi. We analyzed 97 molars according to the ear stages of Simpson and Paula-Couto (1957), and developed a morphometric ear index. The population structure (proportion of immature, subadult, adult, mature adult and senile adult individuals) was identified, and these five age classes were compared to those of extant elephant populations and defined with social implications. The analysis made possible to establish that the population is largely composed of adults: 14.89% are immature individuals, 23.04% subadults, 27.65% adults, 17.21% mature adults and another 17.21% senile adults. Based on population structure, we do not discard the possibility that the fossil population was stable or in recovery, and/or was experiencing a high-predation period on younger individuals. The number of individuals composing the past population studied here could suggest that the occupied environment was open due to comparisons to populations of extant elephants. We consider this population as an aggregation of family units, which suggests a time of low environmental humidity. Based on literature and our findings, their extinction appears to be regional and probably related to a catastrophic event.

  15. Dental microwear patterns of extant and extinct Muridae (Rodentia, Mammalia): ecological implications

    NASA Astrophysics Data System (ADS)

    Gomes Rodrigues, Helder; Merceron, Gildas; Viriot, Laurent

    2009-04-01

    Extant species of Muridae occupy a wide array of habitats and have diverse dietary habits. Consequently, their dental microwear patterns represent a potential clue to better understand the paleoecology of their extinct relatives, which are abundant in many Old World Neogene localities. In this study, dental microwear is investigated for specimens of 17 extant species of murine and deomyine rodents in order to test the reliability of this method and infer dietary preferences on the fossil species Saïdomys afarensis. This extinct form comes from a mid-Pliocene site (AL 327) located at the Hadar Formation (Ethiopia) known to have delivered many hominid specimens of Australopithecus afarensis. A significant correlation between microwear patterns and diet is detected. Thus, grass, fruit, and insect eaters display, respectively, high amounts of fine scratches, wide scratches, and large pits. Moreover, some aspects of the paleoecology of S. afarensis, including feeding habits, could be assessed in regard to its dental microwear pattern. Indeed, it probably had feeding habits similar to that of living grass eaters. These results concur with the presence of open to woodland areas covered by an herbaceous vegetal layer, including monocotyledons, in the vicinity of this mid-Pliocene locality.

  16. Dental microwear patterns of extant and extinct Muridae (Rodentia, Mammalia): ecological implications.

    PubMed

    Rodrigues, Helder Gomes; Merceron, Gildas; Viriot, Laurent

    2009-04-01

    Extant species of Muridae occupy a wide array of habitats and have diverse dietary habits. Consequently, their dental microwear patterns represent a potential clue to better understand the paleoecology of their extinct relatives, which are abundant in many Old World Neogene localities. In this study, dental microwear is investigated for specimens of 17 extant species of murine and deomyine rodents in order to test the reliability of this method and infer dietary preferences on the fossil species Saïdomys afarensis. This extinct form comes from a mid-Pliocene site (AL 327) located at the Hadar Formation (Ethiopia) known to have delivered many hominid specimens of Australopithecus afarensis. A significant correlation between microwear patterns and diet is detected. Thus, grass, fruit, and insect eaters display, respectively, high amounts of fine scratches, wide scratches, and large pits. Moreover, some aspects of the paleoecology of S. afarensis, including feeding habits, could be assessed in regard to its dental microwear pattern. Indeed, it probably had feeding habits similar to that of living grass eaters. These results concur with the presence of open to woodland areas covered by an herbaceous vegetal layer, including monocotyledons, in the vicinity of this mid-Pliocene locality.

  17. Palaeobiology of Hyaenodon exiguus (Hyaenodonta, Mammalia) based on morphometric analysis of the bony labyrinth.

    PubMed

    Pfaff, Cathrin; Nagel, Doris; Gunnell, Gregg; Weber, Gerhard W; Kriwet, Jürgen; Morlo, Michael; Bastl, Katharina

    2017-02-01

    Species of the extinct genus Hyaenodon were among the largest carnivorous mammals from the Late Eocene through Early Miocene in North America, Europe and Asia. The origin, phylogeny and palaeobiology of Hyaenodonta are still ambiguous. Most previous studies focused on teeth and dental function in these highly adapted species, which might be influenced by convergent morphologies. The anatomy of the bony labyrinth in vertebrates is generally quite conservative and, additionally, was used in functional-morphological studies. This study provides the first anatomical description of the bony labyrinth of the extinct European species Hyaenodon exiguus in comparison to selected extant carnivoran taxa discussed from a functional-morphological perspective. Hyaenodon exiguus may have occupied a hyaena-like dietary niche with a semi-arboreal lifestyle, based on the relative height, width and length of the semicircular canals of the inner ear. However, this contradicts previous functional-morphological studies focusing on the diameter of the canals, which presumably represent the signal of locomotion mode.

  18. Osteoderm histology of the Pampatheriidae (Cingulata, Xenarthra, Mammalia): Implications for systematics, osteoderm growth, and biomechanical adaptation.

    PubMed

    Wolf, Dominik; Kalthoff, Daniela C; Sander, P Martin

    2012-04-01

    Pampatheres are extinct, large-bodied cingulates, which share morphological characters with both armadillos and glyptodonts but are considered to be more closely related to the latter. The osteoderm histology of six pampathere taxa was examined and compared to the histology of other cingulate osteoderms. This study investigates the development and functional adaptation of pampathere osteoderms as well as the phylogenetic relationships of the Pampatheriidae within the Cingulata. We found that pampathere osteoderms share a uniform histological organization based on a basic diploe-like structure. After initial stages of intramembranous growth, metaplastic ossification, that is, the direct incorporation and mineralization of pre-existing protein fibers, plays an important role in osteoderm development and provides information on various kinds of soft tissue otherwise not preserved. The latest stages of osteoderm growth are dominated by periosteal bone formation especially in the superficial cortex. Movable band osteoderms show regular arrangements of incorporated fibers that may increase the resistance of particularly weak areas against strain. The histological composition of pampathere osteoderms is plesiomorphic in its basic structure but shows a number of derived features. A unique array of Sharpey's fibers that are incorporated into the bone matrix at sutured osteoderm margins is interpreted as a synapomorphy of pampatheres. The arrangement of dermal fibers in the deep and superficial cortexes supports the close relationship between pampatheres and glyptodonts.

  19. Osteoderm morphology and development in the nine-banded armadillo, Dasypus novemcinctus (Mammalia, Xenarthra, Cingulata).

    PubMed

    Vickaryous, Matthew K; Hall, Brian K

    2006-11-01

    Among modern mammals, armadillos (Xenarthra, Cingulata) are the only group that possesses osteoderms, bony inclusions within the integument. Along the body, osteoderms are organized into five discrete assemblages: the head, pectoral, banded, pelvic, and tail shields. The pectoral, banded, and pelvic shields articulate to form the carapace. We examined osteoderm skeletogenesis in the armadillo Dasypus novemcinctus using serial and whole-mount histochemistry. Compared with the rest of the skeleton, osteoderms have a delayed onset of development. Skeletogenesis begins as condensations of osteoblasts secreting osteoid, localized within the papillary layer of the dermis. Osteoderm formation is asynchronous both within each shield and across the body. The first osteoderms to mineralize are situated within the pectoral shield of the carapace, followed by elements within the banded, head, pelvic, and tail shields. In general, within each shield ossification begins craniomedially and proceeds caudally and laterally, except over the head, where the earliest elements form over the frontal and parietal bones. The absence of cartilage precursors indicates that osteoderms are dermal elements, possibly related to the all-encompassing vertebrate dermal skeleton (exoskeleton). The mode of development of D. novemcinctus osteoderms is unlike that described for squamate osteoderms, which arise via bone metaplasia, and instead is comparable with intramembranously derived elements of the skull.

  20. Behavioral responses of three armadillo species (Mammalia: Xenarthra) to an environmental enrichment program in Villavicencio, Colombia.

    PubMed

    Cortés Duarte, Alexandra; Trujillo, Fernando; Superina, Mariella

    2016-07-01

    Enrichment is a powerful tool to improve the welfare of animals under human care. Stress-related health and behavioral problems, as well as reproductive failure, are frequent in armadillos (Xenarthra, Cingulata, Dasypodidae) under human care, which hinders the development of successful ex situ conservation programs. Nevertheless, scientific studies on the effect of enrichment programs on armadillos are virtually non-existent. The objective of this study was to assess the impact of an enrichment program on the behavior of armadillos under human care. The behavior of 12 individuals of three species (Dasypus novemcinctus, D. sabanicola, and Cabassous unicinctus) maintained at Finca El Turpial, Villavicencio, Colombia, was recorded using scan sampling during three daily time blocks of 2 hr each before (4 weeks) and after (4 weeks) implementing an enrichment program. Enrichment did not stimulate the armadillos to change or extend their activity period. In general, activity levels were low during the entire study, and virtually no activity was recorded in the morning in any species, neither without nor with enrichment. The latter did, however, improve welfare by reducing abnormal and increasing natural foraging behaviors. All species were attracted by artificial termite mounds. Dasypus spp. showed special interest in cardboard boxes with food, while Cabassous was mainly attracted to hollow plastic balls filled with food. Our results suggest that separate enrichment programs need to be developed for different armadillo species, and that they should be applied during the time of day at which they are most active. Zoo Biol. 35:304-312, 2016. © 2016 Wiley Periodicals, Inc.

  1. Pelvic peritoneum in male armadillo and anteater (Xenarthra, Mammalia): a comparative survey.

    PubMed

    Rezende, Lorenna Cardoso; Ferreira, Jussara Rocha

    2013-01-01

    The literature supports the hypothesis that the pelvic excavation is the bottom of the abdominal cavity, which is covered by the peritoneal serous membrane in order to promote visceral dynamics. We studied the peritoneum in eight specimens of Xenarthra (Euphractus sexcinctus, Myrmecophaga tridactyla and Tamandua tetradactyla). The animals were fixed in formaldehyde (10%). For description and analyzes of the pelvic peritoneum, dissection and photo documentation were performed. We saw that the parietal serous membrane reflected, involving the pelvic viscera. The urorectal septum is the floor of the higher pelvis as a serosa reflection between the bladder and the rectum. The bladder and gonads are completely peritonized in adult armadillo. In anteaters and young armadillos, the testicles are in a position analogous to the uterus, joined by the conjunctive septum at the midline and along with the bladder, they partially project to the higher and lower pelvis. In Myrmecophagidae, vesicogenital, rectogenital and sacrorectal recesses were observed. In Dasypodidae, the recesses are similar to those of other recent vertebrates.

  2. Spermatogenesis is seasonal in the large hairy armadillo, Chaetophractus villosus (Dasypodidae, Xenarthra, Mammalia).

    PubMed

    Luaces, Juan P; Rossi, Luis F; Merico, Valeria; Zuccotti, Maurizio; Redi, Carlo A; Solari, Alberto J; Merani, Maria S; Garagna, Silvia

    2013-01-01

    Very little is known about the distinct reproductive biology of armadillos. Very few studies have investigated armadillo spermatogenesis, with data available only for Euphractus sexcinctus and Dasypus novemcinctus. In the present study, we analysed male germ cell differentiation in the large hairy armadillo Chaetophractus villosus throughout the year, describing a cycle of the seminiferous epithelium made of eight different stages. Evaluation of the testis/body mass ratio, analysis of the architecture of the seminiferous epithelium and the frequency of defective seminiferous tubules allowed identification of a temporal interruption of spermatogenesis during the period between mid-May to July (mid-end autumn) in correlation with very low testosterone levels. Overall, these results suggest that spermatogenesis is seasonal in C. villosus.

  3. Observations on fur development in echidna (Monotremata, Mammalia) indicate that spines precede hairs in ontogeny.

    PubMed

    Alibardi, Lorenzo; Rogers, George

    2015-04-01

    In the primitive mammal echidna, the initial 2-3 generations of skin appendages produced from birth forms spines and only later true hairs appear. Microscopy on preserved museum specimens reveals that the morphogenesis of spines and hairs is similar but that a larger dermal papilla is formed in spines. The growing shaft comprises a medulla surrounded by a cortex and by an external cuticle. A thick inner root sheath made of cornified cells surrounds the growing shaft inside the spine canal that eventually exits with a pointed tip. Hairs develop later with the same modality of spines but have a smaller papilla and give rise to a fur coat among spines. Therefore the integument of developing echidnas initially produces spines from large dermal papillae but the reduction in size of the papillae later determines the formation of hairs. Although the morphogenesis of spines and hairs can represent a case of specialization in this species, the primitive mammalian characteristics of echidnas has also inspired new speculations on the evolution of the mammalian hair from mammalian-like reptiles with a spiny coat. The resemblance in the morphogenesis between spines and hairs has suggested some hypothesis on hair evolution, in particular that hairs might be derived from the reduction of protective large spines present in ancient mammalian-like reptiles possibly derived from the reduction of pre-existing pointed scales. The hypothesis suggests that spines became reduced and internalized in the skin forming hairs.

  4. Bat diversity of Ilha da Marambaia, Southern Rio de Janeiro State, Brazil (Chiroptera, Mammalia).

    PubMed

    Lourenço, E C; Costa, L M; Silva, R M; Esbérard, C E L

    2010-08-01

    Few sites have been well sampled for bats, and samplings in islands are even scarcer. Therefore, the objectives of the present study were: (1) to list the bat species of Ilha da Marambaia; (2) to compare richness, abundance and biomass of bat guilds found there; (3) to analyse abundance patterns of bat species; and (4) to compare richness, abundance and composition of the bat fauna among different kinds of environment. To capture bats we used mist nets set in five different environments, totalising 3559.2 net-hours, during 37 nights between October 2006 and August 2008. A total of 1,133 captures were accomplished, comprising 34 species from five families. The most abundant species was Molossus molossus. Frugivorous bats exhibited higher richness, abundance and biomass if compared to other guilds. Most species (N = 22) exhibited abundances between 1 to 10% of all captures. Sixteen species were restricted to just one of the environments sampled. The high richness may be attributed to sampling carried out in several environments, and to the capture of insectivorous species over water bodies.

  5. Phylogeny of the Ferungulata (Mammalia: Laurasiatheria) as determined from phylogenomic data

    PubMed Central

    Hou, Zhuo-cheng; Romero, Roberto; Wildman, Derek E.

    2012-01-01

    Great progress has been made toward resolving the evolutionary relationships among extant mammals, yet there are still areas of disagreement. The relationships among ferungulates that have high quality draft genome sequences available (i.e. dog, cow, horse) are unresolved, and thus we examined their phylogeny using currently known mammalian 1:1 orthologs. This dataset consists of 40 million base pairs from 2705 protein-coding genes. Maximum likelihood and Bayesian analyses of the combined and individual gene phylogenies strongly support a sister grouping of cow and horse to the exclusion of dog although topology tests could not rule out a horse and dog sister group relationship. PMID:19435603

  6. Biology and impacts of Pacific island invasive species 9. Capra hircus, the feral goat, (Mammalia: Bovidae)

    USGS Publications Warehouse

    Chynoweth, Mark W.; Litton, Creighton M.; Lepczyk, Christopher A.; Hess, Steve A.; Cordell, Susan

    2013-01-01

    Domestic goats, Capra hircus, were intentionally introduced to numerous oceanic islands beginning in the sixteenth century. The remarkable ability of C. hircus to survive in a variety of conditions has enabled this animal to become feral and impact native ecosystems on islands throughout the world. Direct ecological impacts include consumption and trampling of native plants, leading to plant community modification and transformation of ecosystem structure. While the negative impacts of feral goats are well-known and effective management strategies have been developed to control this invasive species, large populations persist on many islands. This review summarizes the impacts of feral goats on Pacific island ecosystems, and the management strategies available to control this invasive species.

  7. The Hand of Cercopithecoides williamsi (Mammalia, Primates): Earliest Evidence for Thumb Reduction among Colobine Monkeys

    PubMed Central

    Frost, Stephen R.; Gilbert, Christopher C.; Pugh, Kelsey D.; Guthrie, Emily H.; Delson, Eric

    2015-01-01

    Thumb reduction is among the most important features distinguishing the African and Asian colobines from each other and from other Old World monkeys. In this study we demonstrate that the partial skeleton KNM-ER 4420 from Koobi Fora, Kenya, dated to 1.9 Ma and assigned to the Plio-Pleistocene colobine species Cercopithecoides williamsi, shows marked reduction of its first metacarpal relative to the medial metacarpals. Thus, KNM-ER 4420 is the first documented occurrence of cercopithecid pollical reduction in the fossil record. In the size of its first metacarpal relative to the medial metacarpals, C. williamsi is similar to extant African colobines, but different from cercopithecines, extant Asian colobines and the Late Miocene colobines Microcolobus and Mesopithecus. This feature clearly links the genus Cercopithecoides with the extant African colobine clade and makes it the first definitive African colobine in the fossil record. The postcranial adaptations to terrestriality in Cercopithecoides are most likely secondary, while ancestral colobinans (and colobines) were arboreal. Finally, the absence of any evidence for pollical reduction in Mesopithecus implies either independent thumb reduction in African and Asian colobines or multiple colobine dispersal events out of Africa. Based on the available evidence, we consider the first scenario more likely. PMID:25993410

  8. Red pandas (Mammalia, Carnivora: Parailurus) in the biomes of North Eurasia and North America

    NASA Astrophysics Data System (ADS)

    Matishov, G. G.; Kalmykov, N. P.

    2011-05-01

    The discovery of the Pliocene red panda ( Parailurus) in the West Transbaikal area, as well as Asian raccoons in North Eurasia and North America, indicates that forested areas with bamboo bushes were wide-spread in the Holarctic during the Neogene. During the Late Pliocene, due to a gradual cooling of the climate, altiplanation, and other factors, their habitat started disintegrating, and red pandas began dying out, surviving only in China.

  9. Genetic variations of Turkish bank vole, Myodes glareolus (Mammalia: Rodentia) inferred from mtDNA.

    PubMed

    Çolak, Reyhan; Olgun Karacan, Gül; Kandemir, Irfan; Çolak, Ercüment; Kankiliç, Teoman; Yigit, Nuri; Michaux, Johan

    2016-11-01

    The bank vole, Myodes glareolus, lives in deciduous forests throughout the Palearctic region. In Turkey, this species is distributed only in northern Anatolia (the Black Sea region) where these forests exist. This study reveals genetic differentiation among bank vole populations based on two regions of mitochondrial DNA (cytochrome b and D-loop). Populations in northern Anatolia are divided into two genetic lineages (the "eastern" and "western Black Sea" lineages) by the Kızılırmak Valley. While the western Black Sea lineage is close to the Balkan lineage, in accordance with their geographical proximities, surprisingly, the Uludag lineage, also situated in Western Turkey appears related to the eastern Black Sea population. The divergence time analyses suggest a separation between the Balkan and Turkish groups around 0.26 Mya, whereas the split between the eastern and western Black sea lineages appeared a little bit later (0.20 Mya). Our results suggest that regional refuges existed for this species in Turkey and that small-scale habitat fragmentations led to genetic differentiations between Myodes populations.

  10. Arthropods (Acari, Mallophaga, Siphonaptera) collected from Procyon lotor (Linnaeus, 1758) (Mammalia, Carnivora, Procyonidae) in Poland.

    PubMed

    Haitlinger, Ryszard; Łupicki, Dariusz

    2009-01-01

    From 9 specimens of Procyon lotor collected in vicinity of Dobroszyn and Górzyca (Lubuskie province) 61 arthropods of 6 species were obtained: Siphonaptera (one specimen), Acari (3 species), Phthiraptera (one specimen--Trichodectes octomaculatus; new species to fauna of Poland) and one specimen of Psocoptera.

  11. Opossums (Mammalia: Didelphidae) in the diets of Neotropical pitvipers (Serpentes: Crotalinae): evidence for alternative coevolutionary outcomes?

    PubMed

    Voss, Robert S

    2013-05-01

    Opossums and pitvipers are sympatric throughout most of the New World, but trophic relationships between these speciose clades have only recently attracted the attention of researchers. Although it is now known that some venom-resistant opossums prey on pitvipers, a review of the literature on diets shows that some Neotropical pitvipers prey on opossums. Interestingly, some pitviper species prey on opossums known or suspected to be venom resistant. If venom resistance and venom potency are coevolved traits, then these observations suggest that alternative outcomes may result in role-switching between victims and exploiters. Because molecular antagonists (e.g., venom toxins and toxin-neutralizing serum proteins) that could mediate such outcomes have been plausibly identified, this system is a potentially fruitful field for evolutionary research.

  12. Digital cranial endocast of Hyopsodus (Mammalia, "Condylarthra"): a case of paleogene terrestrial echolocation?

    PubMed

    Orliac, Maeva J; Argot, Christine; Gilissen, Emmanuel

    2012-01-01

    We here describe the endocranial cast of the Eocene archaic ungulate Hyopsodus lepidus AMNH 143783 (Bridgerian, North America) reconstructed from X-ray computed microtomography data. This represents the first complete cranial endocast known for Hyopsodontinae. The Hyopsodus endocast is compared to other known "condylarthran" endocasts, i. e. those of Pleuraspidotherium (Pleuraspidotheriidae), Arctocyon (Arctocyonidae), Meniscotherium (Meniscotheriidae), Phenacodus (Phenacodontidae), as well as to basal perissodactyls (Hyracotherium) and artiodactyls (Cebochoerus, Homacodon). Hyopsodus presents one of the highest encephalization quotients of archaic ungulates and shows an "advanced version" of the basal ungulate brain pattern, with a mosaic of archaic characters such as large olfactory bulbs, weak ventral expansion of the neopallium, and absence of neopallium fissuration, as well as more specialized ones such as the relative reduction of the cerebellum compared to cerebrum or the enlargement of the inferior colliculus. As in other archaic ungulates, Hyopsodus midbrain exposure is important, but it exhibits a dorsally protruding largely developed inferior colliculus, a feature unique among "Condylarthra". A potential correlation between the development of the inferior colliculus in Hyopsodus and the use of terrestrial echolocation as observed in extant tenrecs and shrews is discussed. The detailed analysis of the overall morphology of the postcranial skeleton of Hyopsodus indicates a nimble, fast moving animal that likely lived in burrows. This would be compatible with terrestrial echolocation used by the animal to investigate subterranean habitat and/or to minimize predation during nocturnal exploration of the environment.

  13. White-toothed shrews (Mammalia, Soricomorpha, Crocidura) of coastal islands of Vietnam

    PubMed Central

    Abramov, Alexei V.; Bannikova, Anna A.; Rozhnov, Viatcheslav V.

    2012-01-01

    Abstract New findings of the white-toothed shrews (Crocidura spp.) from offshore islands of Vietnam are reported. The species identifications have been confirmed by the analysis of complete mitochondrial cytochrome b gene (1140 bp). Crocidura phuquocensis is the only species found in the Phu Quoc Island. Crocidura fuliginosa has been recorded from two islands of the Con Dao Archipelago (Con Son and Bai Canh). The occurrence of Crocidura fuliginosa in Vietnam has been genetically confirmed for the first time. Crocidura attenuata has been collected from the Cat Ba Island for the first time, and this finding corresponds well with the proposal that the species’ distribution is confined to the north and east of the Red River only. PMID:22855639

  14. A reassessment of the taxonomic status of Paraglyptodon Castellanos, 1932 (Mammalia, Cingulata, Glyptodontia)

    NASA Astrophysics Data System (ADS)

    Cruz, Laura E.; Fernicola, Juan C.; Taglioretti, Matias; Toledo, Nestor

    2016-03-01

    Castellanos described and published about new genera of glyptodonts, according to a phylogenetic scheme mainly based on the evolution of the external surface of the dorsal carapace. Among these new genera, Castellanos proposed Paraglyptodon as the predecessor of Glyptodon, and included within Paraglyptodon all known species of Glyptodontinae recovered from "horizontes pre-Ensenadenses", and within Glyptodon all known species from "Horizontes pampeanos", restricting the latter to the Quaternary. All the species that belong to Paraglyptodon, that is Paraglyptodon chapalmalensis, Paraglyptodon uquiensis, Paraglyptodon dubius, and Paraglyptodon paranensis were established based on one, two or few osteoderms, mostly from the dorsal carapace. Regarding P. paranensis and P. dubius, Oliva and collaborators consider the first as a nomen vanum, representing an indeterminate Glyptodontinae, and the second as a synonym of P. chapalmalensis. Upon re-examination of the holotypes of P. chapalmalensis and P. uquiensis together with their comparison with other well-known specimens of glyptodonts, mainly with Glyptodon (of both juvenile and adult stages), we found the same ornamentation in different sections of the dorsal carapaces, particularly in P. chapalmalensis and in juvenile stages of Glyptodon spp. We could not identify features that would allow us to make a distinction between the holotype of P. uquiensis and Glyptodon spp. Therefore, we consider that a new taxon guide for naming the Upper Chapadmalalan biozone is necessary. The biostratigraphic range of Glyptodon could possibly be extended to the late Pliocene. However, new records and studies are needed to verify the existence of this taxon in the Chapadmalalan Stage/Age in its type locality.

  15. Molecular phylogeny of the Herpestidae (Mammalia, Carnivora) with a special emphasis on the Asian Herpestes.

    PubMed

    Patou, Marie-Lilith; McLenachan, Patricia A; Morley, Craig G; Couloux, Arnaud; Jennings, Andrew P; Veron, Géraldine

    2009-10-01

    Until now, phylogenetic studies of the mongooses (Carnivora, Herpestidae) have not included an exhaustive sampling of the Asian members of this family. In this study, we used mitochondrial (Cytochrome b and ND2), nuclear (beta-fibrinogen intron 7 and Transthyretin intron 1) sequences from almost all of the recognized mongoose species to produce a well-resolved phylogeny of the Herpestidae. We also performed molecular dating analyses to infer divergence dates of the different lineages within the Herpestidae. Our results confirmed the paraphyly of the Herpestes genus and other phylogenetic relationships, which previously had only been moderately supported. The Asian herpestid species were found to form a monophyletic group within the Herpestidae. Within the Asian species, a cyto-nuclear conflict was discovered between the small Indian mongoose (Herpestes auropunctatus), the Indian gray mongoose (Herpestes edwardsii) and the Javan mongoose (Herpestes javanicus), which may have occurred through interspecific hybridization. This study inferred an Early Miocene origin for the Herpestidae and a Middle Miocene origin for the Asian mongooses.

  16. Late Pleistocene carnivores (Carnivora: Mammalia) from a cave sedimentary deposit in northern Brazil.

    PubMed

    Rodrigues, Shirlley; Avilla, Leonardo S; Soibelzon, Leopoldo H; Bernardes, Camila

    2014-11-28

    The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI). Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM), at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado.

  17. Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae)

    PubMed Central

    Matte, Eunice M.; Castilho, Camila S.; Miotto, Renata A.; Sana, Denis A.; Johnson, Warren E.; O’Brien, Stephen J.; de Freitas, Thales R. O.; Eizirik, Eduardo

    2013-01-01

    The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species’ molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America. PMID:24385863

  18. Late Pleistocene carnivores (Carnivora: Mammalia) from a cave sedimentary deposit in northern Brazil.

    PubMed

    Rodrigues, Shirlley; Avilla, Leonardo S; Soibelzon, Leopoldo H; Bernardes, Camila

    2014-12-01

    The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI). Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM), at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado.

  19. Comparative study of notoungulate (Placentalia, Mammalia) bony labyrinths and new phylogenetically informative inner ear characters

    PubMed Central

    Macrini, Thomas E; Flynn, John J; Ni, Xijun; Croft, Darin A; Wyss, André R

    2013-01-01

    The phylogenetic relationships of notoungulates, an extinct group of predominantly South American herbivores, remain poorly resolved with respect to both other placental mammals and among one another. Most previous phylogenetic analyses of notoungulates have not included characters of the internal cranium, not least because few such features, including the bony labyrinth, have been described for members of the group. Here we describe the inner ears of the notoungulates Altitypotherium chucalensis (Mesotheriidae), Pachyrukhos moyani (Hegetotheriidae) and Cochilius sp. (Interatheriidae) based on reconstructions of bony labyrinths obtained from computed tomography imagery. Comparisons of the bony labyrinths of these taxa with the basally diverging notoungulate Notostylops murinus (Notostylopidae), an isolated petrosal from Itaboraí, Brazil, referred to Notoungulata, and six therian outgroups, yielded an inner ear character matrix of 25 potentially phylogenetically informative characters, 14 of them novel to this study. Two equivocally optimized character states potentially support a pairing of Mesotheriidae and Hegetotheriidae, whereas four others may be diagnostic of Notoungulata. Three additional characters are potentially informative for diagnosing more inclusive clades: one for crown Placentalia; another for a clade containing Kulbeckia, Zalambdalestes, and Placentalia; and a third for Eutheria (crown Placentalia plus stem taxa). Several other characters are apomorphic for at least one notoungulate in our study and are of potential interest for broader taxonomic sampling within Notoungulata to clarify currently enigmatic interrelationships. Measures of the semicircular canals were used to infer agility (e.g. capable of quick movements vs. lethargic movements) of these taxa. Agility scores calculated from these data generally corroborate interpretations based on postcranial remains of these or closely related species. We provide estimates of the low-frequency hearing limits in notoungulates based on the ratio of radii of the apical and basal turns of the cochlea. These limits range from 15 Hz in Notostylops to 149 Hz in Pachyrukhos, values comparable to the Asian elephant (Elephas maximus) and the California sea lion (Zalophus californianus) when hearing in air, respectively. PMID:24102069

  20. Characterisation of glycoconjugate sugar residues in the vomeronasal organ of the armadillo Chaetophractus villosus (Mammalia, xenarthra)

    PubMed Central

    CARMANCHAHI, P. D.; FERRARI, C. C.; ALDANA MARCOS, H. J.; AFFANNI, J. M.; SONEZ, C. A.; PAZ, D. A.

    2000-01-01

    Conventional carbohydrate histochemistry and the binding patterns of 21 lectins were analysed to characterise the glycoconjugate content in the components of the vomeronasal organ of the armadillo Chaetophractus villosus. The mucomicrovillous complex of the sensory epithelium bound most of the lectins studied. No reaction was observed with Con A, PSA, S-Con A and SBA, and the sustentacular cells were stained with UEA-I, DSL, LEL, STL and Con A. The vomeronasal receptor neurons were labelled with S-WGA, WGA, PNA, UEA-I, STL, Con A, S-Con A, ECL and RCA120. The basal cell layer reacted with S-WGA, WGA, LCA, UEA-I, DSL, LEL, STL, Con A, JAC and VVA. The nonsensory epithelium exhibited a differential staining in relation to the different components. The mucociliary complex stained with ECL, DBA, JAC, RCA120, STL, LCA, PHA-E, PHA-L, LEL, BSL-I and VVA. However, SJA and UEA-I stained the mucus complex lining a subpopulation of columnar cells. The cytoplasm and cell membranes of columnar cells was labelled with DBA, DSL and LCA. The apical region of these cells exhibited moderate reactivity with LEL and SJA. None of the lectins bound specifically to secretory granules of the nonsecretory cells. Basal cells of the nonsensory epithelium were labelled with DSL, LEL, LCA, BSL-I and STL. The vomeronasal glands showed a positive reaction with WGA, DSL, LEL, LCA, DBA, PNA, RCA120 and SBA. Subpopulations of acinar cells were observed with ECL, S-WGA, Con A, S-Con A and DBA. PNA and RCA120 stained the cells lining the glandular ducts. In comparison with previous results obtained in the olfactory mucosa of the same group of armadillos, the carbohydrate composition of the vomeronasal organ sensory epithelium differed from the olfactory sensory epithelium. This is probably related to the different nature of molecules involved in the perireceptor processes. PMID:10853958

  1. [Helminth fauna in insectivores (Mammalia: Insectivora) of canal banks in meliorated territories].

    PubMed

    Shimalov, V V

    2007-01-01

    Helminth fauna of Insectivora was investigated in canal banks situated in meliorated territories of Belorussian Polesie during 1996-1999. Thirty-three helminth species were found in the animals examined. Most of the parasites are usual in common shrew Sorex araneus L., which is a predominate insectivore species in canal banks.

  2. Gamasine mite (Parasitiformes: Mesostigmata) infestations of small mammals (Mammalia: Rodentia, Insectivora) in Turkey.

    PubMed

    Cicek, Hatice; Stanyukovich, Maria; Yağci, Sukran; Aktaş, Metin; Karaer, Zafer

    2008-01-01

    The present study was conducted on small mammals from different locations in Turkey. One hundred twenty- three individuals representing 11 species of rodents and insectivora were investigated for mite ectoparasites. A total of 126 gamasine mites were collected from 96 individuals (78.1%) of 6 species of small mammals. Five gamasine families were recorded: Laelapidae, Hirstionyssidae, Haemogamasidae, Macronyssidae and Macrochelidae. Laelaps jettmari Vitzthum (72 species) was predominant and found mainly on Mus musculus (Linnaeus) and Cricetulus migratorius (Pallas). New species of gamasine mites and host records for Turkey are given.

  3. Mandible shape and dwarfism in squirrels (Mammalia, Rodentia): interaction of allometry and adaptation

    NASA Astrophysics Data System (ADS)

    Hautier, Lionel; Fabre, Pierre-Henri; Michaux, Jacques

    2009-06-01

    Squirrels include several independent lineages of dwarf forms distributed into two ecological groups: the dwarf tree and flying squirrels. The mandible of dwarf tree squirrels share a highly reduced coronoid process and a condylar process drawn backwards. Dwarf flying squirrels on the other hand, have an elongated coronoid process and a well-differentiated condylar process. To interpret such a difference, Elliptic Fourier Transform was used to evaluate how mandible shape varies with dwarfism in sciurids. The results obtained show that this clear-cut difference cannot be explained by a simple allometric relationship in relation with size decrease. We concluded that the retention of anteriorly positioned eye sockets, in relation with distance estimation, allowed the conservation of a well-differentiated coronoid process in all flying species, despite the trend towards its reduction observed among sciurids as their size decreases.

  4. Brazilian distribution of Amblyomma varium Koch, 1844 (Acari: Ixodidae), a common parasite of sloths (Mammalia: Xenarthra).

    PubMed

    Marques, Sandro; Barros-Battesti, Darci Moraes; Faccini, João Luiz Horacio; Onofrio, Valeria Castilho

    2002-12-01

    Amblyomma varium, commonly known in Brazil as the "carrapato-gigante-da-pregui a" (sloth's giant tick) is found from southern Central America to Argentina. The present study adds information on the geographical distribution of A. varium, as well as on their hosts, based on material deposited in the main Brazilian collections and on the available literature. Eighty-two vials, containing 191 adult specimens, deposited in five Acari collections between 1930 and 2001, were examined. These vials included data on the host and collection localities. The biology of A. varium is unknown. However it is known that, during the adult stage, the tick presents a high host specificity and is found almost exclusively on the sloths Bradypus tridactylus, B. variegatus, B.torquatus (Bradypodidae), Choloepus hoffmanni and C. didactylus (Megalonychidae). Based on the material examined, the states of Rond nia, Amazonas, Bahia and Alagoas are newly assigned to geographic distribution of A. varium in Brazil.

  5. A time-calibrated species-level phylogeny of bats (Chiroptera, Mammalia)

    PubMed Central

    Agnarsson, Ingi; Zambrana-Torrelio, Carlos M.; Flores-Saldana, Nadia Paola; May-Collado, Laura J.

    2011-01-01

    Despite their obvious utility, detailed species-level phylogenies are lacking for many groups, including several major mammalian lineages such as bats. Here we provide a cytochrome b genealogy of over 50% of bat species (648 terminal taxa). Based on prior analyzes of related mammal groups, cytb emerges as a particularly reliable phylogenetic marker, and given that our results are broadly congruent with prior knowledge, the phylogeny should be a useful tool for comparative analyzes. Nevertheless, we stress that a single-gene analysis of such a large and old group cannot be interpreted as more than a crude estimate of the bat species tree. Analysis of the full dataset supports the traditional division of bats into macro- and microchiroptera, but not the recently proposed division into Yinpterochiroptera and Yangochiroptera. However, our results only weakly reject the former and strongly support the latter group, and furthermore, a time calibrated analysis of a pruned dataset where most included taxa have the entire 1140bp cytb sequence finds monophyletic Yinpterochiroptera. Most bat families and many higher level groups are supported, however, relationships among families are in general weakly supported, as are many of the deeper nodes of the tree. The exceptions are in most cases apparently due to the misplacement of species with little available data, while in a few cases the results suggest putative problems with current classification, such as the non-monophyly of Mormoopidae. We provide this phylogenetic hypothesis, and an analysis of divergence times, as tools for evolutionary and ecological studies that will be useful until more inclusive studies using multiple loci become available. PMID:21327164

  6. Identification of Bacterial Specialists in Hosts belonging to Aves, Mammalia, and Pisces

    EPA Science Inventory

    Only a portion of bacteria found in animal guts are able to establish specific associations within animal hosts. Taxa that have formed these specialized relationships may have played a prominent role in host evolution and may also contribute significantly to current host physiolo...

  7. The taxonomic status of the Yucatan brown brocket, Mazama pandora (Mammalia: Cervidae)

    USGS Publications Warehouse

    Medellin, R.A.; Gardner, A.L.; Aranda, J.M.

    1998-01-01

    The Yucatan brown brocket deer, described as Mazama pandora, is now treated as a subspecies of either the common brown brocket, Mazama gouazoubira, or of the red brocket, M. americana. Analysis of brocket deer from Mexico and Central and South America, reveals that the Yucatan brown brocket is sympatric with the red brocket in Mexico and, while similar to M. gouazoubira, warrents recognition as a separate species.

  8. Ectoparasites of bats (Mammalia: Chiroptera) in Atlantic forest fragments in north-eastern Brazil.

    PubMed

    Bezerra, Rayanna Hellem Santos; de Vasconcelos, Pedro Fonseca; Bocchiglieri, Adriana

    2016-10-01

    In Brazil, most studies involving parasites of bats (bat flies) treat the mid-west, south-east, and south of the country. This work aimed to characterize the ectoparasites community associated with bats in the Atlantic forest in the state of Sergipe, north-eastern Brazil. Sampling was conducted between January and June 2013 in the Serra de Itabaiana National Park (PNSI) and between November 2013 and June 2015 in the Wildlife Refuge Mata do Junco (RVSMJ). Parasitological indexes were determined, and the influence of host sex and the seasonality in prevalence rates and mean intensity for the most abundant parasites was evaluated. Some 129 parasites were collected in PNSI and 296 in RVSMJ, and 100 and 70.6 %, respectively, belong to the family Streblidae. The differences in parasitological rates in Sergipe in relation to other studies may be associated with the environmental characteristics and the composition of the host community. The influence of sex and the seasonal prevalence of Speiseria ambigua and Trichobius joblingi, associated with Carollia perspicillata, may be associated with a lower rate of female captures and low sampling in the dry season. This is a pioneer study in Sergipe that reveals the occurrence of 16 species of streblids and representatives of Acari and Basilia spp., highlighting the need for more studies to increase the wealth and understanding of host-parasite associations in the state.

  9. A new Early Oligocene peradectine marsupial (Mammalia)from the Burqin region of Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Ni, Xijun; Meng, Jin; Wu, Wenyu; Ye, Jie

    2007-03-01

    Tertiary marsupial records are very scarce in Asia. A new peradectine marsupial, Junggaroperadectes burqinensis gen. et sp. nov., is reported from the Early Oligocene Keziletuogayi Formation in the Burqin region, Xinjiang, China. This new species is based on a single right upper M2. The tooth possesses a straight centrocrista, a characteristic of peradectines. Its main cusps lean buccally, with the paracone being smaller and lower than the metacone. The conules and stylar cusps are weakly developed. These characters distinguish J. burqinensis from Euro-American Tertiary peradectines, but they also imply a close phylogenetic relationship to Siamoperadectes and Sinoperadectes, two Asian Early Miocene peradectines.

  10. Philodryas chamissonis (Reptilia: Squamata: Colubridae) preys on the arboreal marsupial Dromiciops gliroides (Mammalia: Microbiotheria: Microbiotheriidae).

    PubMed

    Muñoz-Leal, S; Ardiles, K; Figueroa, R A; González-Acuña, D

    2013-02-01

    Philodryas chamissonis, the Chilean long-tailed snake, is a diurnal predator mainly of Liolaemus lizards, but also of amphibians, birds, rodents and juvenile rabbits. Dromiciops gliroides (Colocolo opossum) is an arboreal marsupial endemic of temperate rainforest of southern South America. Little information is available about this marsupial's biology and ecology. Here we report the predation of one Colocolo opossum by an adult female P. chamissonis in a mixed Nothofagus forest, composed mainly by N. dombeyi, N. glauca and N. alpina trees, in the "Huemules de Niblinto" National Reserve, Nevados de Chillán, Chile. Since these two species have different activity and habitat use patterns, we discuss how this encounter may have occurred. Although it could just have been an opportunistic event, this finding provides insights into the different components of food chains in forest ecosystems of Chile.

  11. Filling phylogenetic gaps and the biogeographic relationships of the Octodontidae (Mammalia: Hystricognathi).

    PubMed

    Suárez-Villota, Elkin Y; González-Wevar, Claudio A; Gallardo, Milton H; Vásquez, Rodrigo A; Poulin, Elie

    2016-12-01

    Endemic to South America, octodontid rodents are remarkable by being the only mammal taxa where allotetraploidy has been documented. The taxon's extensive morpho-physiological radiation associated to niche shifts has allowed testing phylogeographic hypotheses. Using maximum likelihood and Bayesian inference analyses, applied to all nominal species of octodontids, phylogenetic reconstructions based on sequences of 12S rRNA and growth hormone receptor gene are presented. Species boundaries were determined by coalescent analyses and divergence times among taxa were estimated based on mutation rates. Two main clades associated to the Andean orogenesis were recognized. The essentially western clade comprises genera Aconaemys, Octodon, Spalacopus, and Octodontomys whereas the eastern one included genera Octomys, Pipanacoctomys, Salinoctomys, and Tympanoctomys. Genetic relationships, coalescent analyses, and genetic distance supported the specific status given to Octodon pacificus and that given to Pipanacoctomys aureus as a species of Tympanoctomys. However, these analyses failed to recognize Salinoctomys loschalchalerosorum as a valid taxon considering its position within the diversity of Tympanoctomys barrerae. Although the origin of genome duplication remains contentious, the coincidence of the basal clade split with distinctive modes of karyotypic evolution across the Andes emphasizes the role of physiographic barriers and westerlies in shaping different edaphological conditions, selective grounds, and concomitantly distinct adaptations within the octodontids.

  12. On the Indian crested porcupine, Hystrix indica (Kerr, 1792) in Turkey (Mammalia: Rodentia).

    PubMed

    Arslan, Atilla

    2008-01-15

    This study presents some data about ecological, biological and taxonomical characteristics of Hystrix indica (Kerr, 1792) from Turkey. For this purpose characteristics of burrow, skull, tooth and measurements of external and cranial characters of two female H. indica from Turkey were investigated. It was concluded that our specimens are between the Middle East and Indian sub-region specimens in terms of morphometrical. It was also determined that there were roots in stomach contents of specimens.

  13. Late cenozoic history of the genus Micromys (mammalia, rodentia) in Central Europe.

    PubMed

    Horáček, Ivan; Knitlová, Markéta; Wagner, Jan; Kordos, László; Nadachowski, Adam

    2013-01-01

    Molecular phylogeography suggests that Micromys minutus, the sole extant species of the genus, colonized its extensive range quite recently, during the Late Pleistocene-Holocene period. Rich Pliocene and Pleistocene fossil records both from Europe and China suggest rather continuous and gradual in situ phenotype rearrangements from the Pliocene to the Recent periods. To elucidate the discrepancy we reexamined a considerable part of the European fossil record of the genus (14 sites from MN15 to Q3, 0.4-4.2 Ma, including the type series of M. preaminutus from MN15 Csarnóta 2), analyzed them with the aid of detailed morphometric comparisons, and concluded that: (a) The European Pliocene form, M. praeminutus, differs significantly from the extant species; (b) it exhibits a broad phenotypic variation covering the presumptive diagnostic characters of MN16 M. caesaris; (c) despite having smaller dimensions, the Early and Middle Pleistocene forms (MN17-Q3, 2.6-0.4 Ma) seem to be closer to M. praeminutus than to the extant species; (d) the extinction of M. praeminutus during Q3 and the re-occupation of its niche by the recent expansion of M. minutus from E-European-C Asiatic sources (suggested by phylogeographic hypotheses) cannot be excluded. Discussing interpretations of the phylogenetic past of the genus we emphasize the distinct history of the West Palearctic clade (Late Miocene-Early Pleistocene) terminating with M. praeminutus and the East Asiatic clade (chalceus, tedfordi, minutus), and the possible identity of the Western clade with the Late Miocene genus Parapodemus.

  14. A new Mammutidae (Proboscidea, Mammalia) from the Late Miocene of Gansu Province, China.

    PubMed

    Mothé, Dimila; Avilla, Leonardo S; Zhao, Desi; Xie, Guangpu; Sun, Boyang

    2016-03-01

    The "Yanghecun specimen", a proboscidean specimen represented by a mandible from Miocene of China and previously described as Gomphotheriidae, is here reviewed and described as a new genus and species of Mammutidae: Sinomammut tobieni. This taxon is a longirostrine mastodon, lacking lower tusks, and bearing a wide last molar with oblique and non-inflated lophids, broad transverse interlophids, and yoke-like wear figures. Phylogenetic analysis of Mammutidae based on dental and mandibular features recovered S. tobieni as sister group of the mastodon Mammut. The longirostrine condition and the well-developed lower incisors seem to be primitive for Mammutidae, while the brevirostry is the derived condition, probably emerged during the middle Miocene (12-11 Mya). However, two derived conditions are recognized to the lower tusks: the absence of lower tusks (S. tobieni) and the occasional presence of vestigial lower tusks (Mammut).

  15. The evolution of orbit orientation and encephalization in the Carnivora (Mammalia).

    PubMed

    Finarelli, John A; Goswami, Anjali

    2009-05-01

    Evolutionary change in encephalization within and across mammalian clades is well-studied, yet relatively few comparative analyses attempt to quantify the impact of evolutionary change in relative brain size on cranial morphology. Because of the proximity of the braincase to the orbits, and the inter-relationships among ecology, sensory systems and neuroanatomy, a relationship has been hypothesized between orbit orientation and encephalization for mammals. Here, we tested this hypothesis in 68 fossil and living species of the mammalian order Carnivora, comparing orbit orientation angles (convergence and frontation) to skull length and encephalization. No significant correlations were observed between skull length and orbit orientation when all taxa were analysed. Significant correlations were observed between encephalization and orbit orientation; however, these were restricted to the families Felidae and Canidae. Encephalization is positively correlated with frontation in both families and negatively correlated with convergence in canids. These results indicate that no universal relationship exists between encephalization and orbit orientation for Carnivora. Braincase expansion impacts orbit orientation in specific carnivoran clades, the nature of which is idiosyncratic to the clade itself.

  16. A new middle eocene whale (Mammalia: Cetacea: Archaeoceti) and associated biota from Georgia

    USGS Publications Warehouse

    Hulbert, R.C.; Petkewich, R.M.; Bishop, G.A.; Bukry, D.; Aleshire, D.P.

    1998-01-01

    A shallow-marine fossil biota was recovered from the Blue Bluff unit (formerly part of the McBean Formation) in the Upper Coastal Plain of eastern Georgia. Biochronologically significant mollusks (e.g., Turritella nasuta, Cubitostrea sellaeformis, Pteropsella lapidosa) and calcareous nannoplankton (e.g., Chiasmolithus solitus, Reticulofenestra umbilica, Cribocentrum reticulatum) indicate a latest Lutetian-earliest Bartonian age, or about 40 to 41 Ma. Georgiacetus vogtlensis new genus and species is described from a well-preserved, partial skeleton. Georgiacetus is the oldest known whale with a true pterygoid sinus fossa in its basicranium and a pelvis that did not articulate directly with the sacral vertebrae, two features whose acquisitions were important steps toward adaptation to a fully marine existence. The posterior four cheek teeth of G. vogtlensis form a series of carnassial-like shearing blades. These teeth also bear small, blunt accessory cusps, which are regarded as being homologous with the larger, sharper accessory cusps of basilosaurid cheek teeth.

  17. Rodents and lagomorphs (Mammalia) from the Hemphillian (late Miocene) of Utah

    USGS Publications Warehouse

    Korth, W.W.; De Blieux, D. D.

    2010-01-01

    Four species of rodents (two heteromyids and two cricetids) and one lagomorph are identified from the late Tertiary Sevier River Formation of Utah. The heteromyids include a new genus and species of heteromyine, Metaliomys sevierensis, which is intermediate in morphology between the Clarendonian and early Hemphillian Diprionomys Kellogg and the extant genera Liomys and Heteromys. A single specimen is referred to Diprionomys sp., cf. D. minimus (Kellogg). The cricetid Paronychomys lemredfieldi Jacobs is known from the Hemphillian of Arizona. The second cricetid is referred to a new genus Basirepomys. Peromyscus pliocenicus Wilson from the Hemphillian of California is designated as the type species of the new genus, to which the new species B. robertsi from Utah is referred. Basirepomys is viewed as intermediate between Peromyscus and the basal neotomyine Repomys May from the late Hemphillian and Blancan. The only lagomorph in the fauna is Hypolagus vetus (Kellogg). Four of the taxa recognized from the Sevier River Formation (Diprionomys, Paronychomys lemredfieldi, Basirepomys, and Hypolagus vetus) are elsewhere known from the Hemphillian of North America. However, it is not possible at this time to determine whether the fauna is early or late Hemphillian. ?? 2010 by the Society of Vertebrate Paleontology.

  18. Bony labyrinth morphometry indicates locomotor adaptations in the squirrel-related clade (Rodentia, Mammalia).

    PubMed

    Pfaff, Cathrin; Martin, Thomas; Ruf, Irina

    2015-06-22

    The semicircular canals (SCs) of the inner ear detect angular acceleration and are located in the bony labyrinth of the petrosal bone. Based on high-resolution computed tomography, we created a size-independent database of the bony labyrinth of 50 mammalian species especially rodents of the squirrel-related clade comprising taxa with fossorial, arboreal and gliding adaptations. Our sampling also includes gliding marsupials, actively flying bats, the arboreal tree shrew and subterranean species. The morphometric anatomy of the SCs was correlated to the locomotion mode. Even if the phylogenetic signal cannot entirely be excluded, the main significance for functional morphological studies has been found in the diameter of the SCs, whereas the radius of curvature is of minor interest. Additionally, we found clear differences in the bias angle of the canals between subterranean and gliding taxa, but also between sciurids and glirids. The sensitivity of the inner ear correlates with the locomotion mode, with a higher sensitivity of the SCs in fossorial species than in flying taxa. We conclude that the inner ear of flying and gliding mammals is less sensitive due to the large information flow into this sense organ during locomotion.

  19. Taxonomic and systematic revisions to the North American Nimravidae (Mammalia, Carnivora)

    PubMed Central

    2016-01-01

    The Nimravidae is a family of extinct carnivores commonly referred to as “false saber-tooth cats.” Since their initial discovery, they have prompted difficulty in taxonomic assignments and number of valid species. Past revisions have only examined a handful of genera, while recent advances in cladistic and morphometric analyses have granted us additional avenues to answering questions regarding our understanding of valid nimravid taxa and their phylogenetic relationships. To resolve issues of specific validity, the phylogenetic species concept (PSC) was utilized to maintain consistency in diagnosing valid species, while simultaneously employing character and linear morphometric analyses for confirming the validity of taxa. Determined valid species and taxonomically informative characters were then employed in two differential cladistic analyses to create competing hypotheses of interspecific relationships. The results suggest the validity of twelve species and six monophyletic genera. The first in depth reviews of Pogonodon and Dinictis returned two valid species (P. platycopis, P. davisi) for the former, while only one for the latter (D. felina). The taxonomic validity of Nanosmilus is upheld. Two main clades with substantial support were returned for all cladistic analyses, the Hoplophoneini and Nimravini, with ambiguous positions relative to these main clades for the European taxa: Eofelis, Dinailurictis bonali, and Quercylurus major; and the North American taxa Dinictis and Pogonodon. Eusmilus is determined to represent a non-valid genus for North American taxa, suggesting non-validity for Old World nimravid species as well. Finally, Hoplophoneus mentalis is found to be a junior synonym of Hoplophoneus primaevus, while the validity of Hoplophoneus oharrai is reinstated. PMID:26893959

  20. Identification of specialists and abundance-occupancy relationships among intestinal bacteria of Aves, Mammalia, and Actinopterygii

    EPA Science Inventory

    The coalescence of next generation DNA sequencing methods, ecological perspectives, and bioinformatics analysis tools is rapidly advancing our understanding of the evolution and function of vertebrate-associated bacterial communities. Delineating host-microbial associations has a...

  1. Functional implications of variation in tooth spacing and crown size in pinnipedimorpha (mammalia: carnivora).

    PubMed

    Churchill, Morgan; Clementz, Mark T

    2015-05-01

    Pinnipeds (seals, sea lions, and walruses) show variation in tooth morphology that relates to ecology. However, crown size and spacing are two aspects of morphology that have not been quantified in prior studies. We measured these characters for nearly all extant pinnipeds and three fossil taxa and then determined the principal sources of variation in tooth size and spacing using principal components (PCAs) and hierarchical cluster analysis (HCA). PCA and HCA showed that species sorted into three groups: taxa with small crowns and large diastemata, taxa with large crowns and small diastemata, and taxa that fell between these two extremes. We then performed discriminant function analysis (DFA) to determine if tooth morphology correlated with foraging strategy or diet. DFA results indicated weak correlation with diet, and stronger correlation with prey capture strategies. Tooth size and spacing were most strongly correlated with the importance of teeth in prey acquisition, with tooth size decreasing and tooth spacing increasing as teeth become less necessary in capturing food items. Taxa which relied on teeth for filtering prey from the water column or processing larger or tougher food items generally had larger crowns and smaller tooth spacing then taxa which swallowed prey whole. We found the fossil taxa Desmatophoca and Enaliarctos were most similar in tooth morphology to extant otariids, suggesting that both taxa were generalist feeders. This study established the relationship between tooth size and feeding behavior, and provides a new tool to explore the paleoecology of fossil pinnipeds and other aquatic tetrapods.

  2. Histological patterns of the intestinal attachment of Corynosoma australe (Acanthocephala: Polymorphidae) in Arctocephalus australis (Mammalia: Pinnipedia).

    PubMed

    Silva, Renato Z; Pereira, Joaber; Cousin, João Carlos B

    2014-12-01

    The mucosal attachment pattern of Corynosoma australe in the intestines of Arctocephalus australis is described. Normal and abnormal tissue were sampled from 32 hosts to be submitted to histological routine protocol to embedding in paraffin and permanent mounting in balsam. Corynosoma australe shows three different degrees of body depth intestinal attachment (BDINA-1-3). BDINA-1: it is exclusive of the small intestine and the parasite attaches on the villi; BDINA-2: parasite affects the Lieberkühn crypts in several depth levels and, BDINA-3: the parasite reaches the submucosa. These attachment patterns alter the mucosa by degeneration and dysfunction due to necrosis of mucosal structure, great quantities of cellular debris and significant reduction of the mucosal thickness. Other aspects are crater-like concave holes (CLCHs) as sites where C. australe could be attached-detached several times according to adult migratory processes within luminal intestine space. The submucosa shows edema probably due to the local mucosal alterations resulting in homeostatic break. There is no severe inflammatory response by host but BDINA-1 to BDINA-3 and CLCH could represent foci to secondary opportunistic infections and significant areas of malabsorption in severally infected hosts contributing to increase clinical signs of preexistent pathologies.

  3. Cope's rule and the evolution of body size in Pinnipedimorpha (Mammalia: Carnivora).

    PubMed

    Churchill, Morgan; Clementz, Mark T; Kohno, Naoki

    2015-01-01

    Cope's rule describes the evolutionary trend for animal lineages to increase in body size over time. In this study, we tested the validity of Cope's rule for a marine mammal clade, the Pinnipedimorpha, which includes the extinct Desmatophocidae, and extant Phocidae (earless seals), Otariidae (fur seals and sea lions), and Odobenidae (walruses). We tested for the presence of Cope's rule by compiling a large dataset of body size data for extant and fossil pinnipeds and then examined how body size evolved through time. We found that there was a positive relationship between geologic age and body size. However, this trend is the result of differences between early assemblages of small-bodied pinnipeds (Oligocene to early Miocene) and later assemblages (middle Miocene to Pliocene) for which species exhibited greater size diversity. No significant differences were found between the number of increases or decreases in body size within Pinnipedimorpha or within specific pinniped clades. This suggests that the pinniped body size increase was driven by passive diversification into vacant niche space, with the common ancestor of Pinnipedimorpha occurring near the minimum adult body size possible for a marine mammal. Based upon the above results, the evolutionary history of pinnipeds does not follow Cope's rule.

  4. The Endemic Insular and Peninsular Species Chaetodipus spinatus (Mammalia, Heteromyidae) Breaks Patterns for Baja California

    PubMed Central

    Álvarez-Castañeda, Sergio Ticul; Murphy, Robert W.

    2014-01-01

    The Baja California peninsula is the second longest, most geographically isolated peninsula on Earth. Its physiography and the presence of many surrounding islands has facilitated studies of the underlying patterns and drivers of genetic structuring for a wide spectrum of organisms. Chaetodipus spinatus is endemic to the region and occurs on 12 associated islands, including 10 in the Gulf of California and two in the Pacific Ocean. This distribution makes it a model species for evaluating natural historical barriers. We test hypotheses associated with the relationship between the range of the species, patterns in other species, and its relationship to Pleistocene-Holocene climatic changes. We analyzed sequence data from mtDNA genes encoding cytochrome b (Cytb) and cytochrome c oxidase subunits I (COI) and III (COIII) in 26 populations including all 12 islands. The matrilineal genealogy, statistical parsimony network and Bayesian skyline plot indicated an origin of C. spinatus in the southern part of the peninsula. Our analyses detected several differences from the common pattern of peninsular animals: no mid-peninsula break exists, Isla Carmen hosts the most divergent population, the population on an ancient southern Midriff island does not differ from peninsular populations, and a mtDNA peninsular discordance occurs near Loreto. PMID:25542029

  5. [Genetic and morphological variation in a partially isolated population of Caucasian shrew sorex Satunini (Mammalia)].

    PubMed

    Grigor'eva, O O; Sychova, V B

    2011-09-01

    Morphological and genetic variation at microsatellite loci of Caucasian shrew Sorex satunini Ogn. is examined and compared with that of the common shrew S. araneus L. Genetic distance at microsatellite loci between the common shrew and Caucasian shrew proved to be threefold higher than between chromosome races of the common shrew. The Caucasian shrew manifested low polymorphism in studies of both microsatellites and morphometric mandibular traits. The heterozygote deficit was also typical. These properties may be a consequence of partial isolation of the population and gene drift.

  6. [Water and energy metabolism in representatives of the genus Martes and Mustela (Mammalia: Mustelidae)].

    PubMed

    Meshcherskiĭ, I G; Rozhnov, V V; Naĭdenko, S V

    2003-01-01

    The quantities of consumed food and water, quantity and moisture content of faeces, as well as quantity and concentration of excreted urine were determined in representatives of Martes--marten (M. martes) and sable (M. zibellina)--as well as in polecat (Mustela putorius). Under the same cage conditions and free access to food, all three species had similar energy value of the daily diet. However, the level of drinking water consumption and the ratio between the quantities of arriving water and energy was reliably higher in both Martes species than in polecat. In addition, both marten and sable featured a much higher rate of evaporation loss in the overall water balance and, consequently, a higher quantity of heat dissipated with evaporation as compared to polecat. Comparison of the obtained and previous data (Sokolov et al., 1995; Rozhnov, 1991) allowed us to propose that the mentioned differences can be specific for representatives of Martes and Mustela genera irrespective of ecological specialization of particular species.

  7. Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae).

    PubMed

    Matte, Eunice M; Castilho, Camila S; Miotto, Renata A; Sana, Denis A; Johnson, Warren E; O'Brien, Stephen J; de Freitas, Thales R O; Eizirik, Eduardo

    2013-12-01

    The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species' molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America.

  8. Karyotypes of two rare rodents, Hapalomys delacouri and Typhlomys cinereus (Mammalia, Rodentia), from Vietnam.

    PubMed

    Abramov, Alexei V; Aniskin, Vladimir M; Rozhnov, Viatcheslav V

    2012-01-01

    Karyotypes of Hapalomys delacouri (Rodentia, Muridae) and Typhlomys cinereus (Rodentia, Platacanthomyidae) from Vietnam are described for the first time. The diploid karyotype of Hapalomys delacouri is 38 (NFa=48), consisting of six pairs of bi-armed and 12 pairs of acrocentric autosomes decreasing in size; plus a large metacentric X chromosome and Y chromosome, also metacentric, that is equal in size to the largest pair of acrocentric autosomes. The newly described karyotype differs significantly from that reported for Hapalomys delacouri from northern Thailand. The latter record very likely represents a different species of Hapalomys, possibly the taxon Hapalomys pasquieri described from north-central Laos.The diploid karyotype of Typhlomys cinereus is 38 (NF=48), consisting of five pairs of meta- to submetacentric and 14 pairs of acrocentric chromosomes varying in size from large to small; sex chromosomes were not defined.

  9. Comparative study on the forefoot and hindfoot intrinsic muscles of some cavioidea rodents (Mammalia, Rodentia).

    PubMed

    Rocha-Barbosa, Oscar; Loguercio, Mariana F C; Renous, Sabine; Gasc, Jean-Pierre

    2007-01-01

    The present study compares the forefoot and hindfoot musculature of five representative species of Cavioidea rodents. In all species, the musculature of both forefeet and hindfeet have the same array regardless of the absence of digit I in the manus of Hydrochaeris hydrochaeris and Cavia porcellus. Our results suggest a tendency in these species towards a three-digit system, with a functional loss of digit V and a predominance of digit III in their forefeet. In the same way, the muscular reduction of digit I in the other rodents analyzed indicates a four-digit system with predominance of digit II in Myoprocta acouchy and Dasyprocta leporina and of digit V in Agouti paca. There seems to be an association between the muscular arrangement and functional axis of the foot, raising the general question why this axis runs between the third and forth digit, or along the third digit.

  10. On the relationship between enamel band complexity and occlusal surface area in Equids (Mammalia, Perissodactyla)

    PubMed Central

    Davis, Edward Byrd

    2016-01-01

    Enamel patterns on the occlusal surfaces of equid teeth are asserted to have tribal-level differences. The most notable example compares the Equini and Hipparionini, where Equini have higher crowned teeth with less enamel-band complexity and less total occlusal enamel than Hipparionini. Whereas previous work has successfully quantified differences in enamel band shape by dividing the length of enamel band by the square root of the occlusal surface area (Occlusal Enamel Index, OEI), it was clear that OEI only partially removes the effect of body size. Because enamel band length scales allometrically, body size still has an influence on OEI, with larger individuals having relatively longer enamel bands than smaller individuals. Fractal dimensionality (D) can be scaled to any level, so we have used it to quantify occlusal enamel complexity in a way that allows us to get at an accurate representation of the relationship between complexity and body size. To test the hypothesis of tribal-level complexity differences between Equini and Hipparionini, we digitally traced a sample of 98 teeth, one tooth per individual; 31 Hipparionini and 67 Equini. We restricted our sampling to the P3-M2 to reduce the effect of tooth position. After calculating the D of these teeth with the fractal box method which uses the number of boxes of various sizes to calculate the D of a line, we performed a t-test on the individual values of D for each specimen, comparing the means between the two tribes, and a phylogenetically informed generalized least squares regression (PGLS) for each tribe with occlusal surface area as the independent variable and D as the dependent variable. The slopes of both PGLS analyses were compared using a t-test to determine if the same linear relationship existed between the two tribes. The t-test between tribes was significant (p < 0.0001), suggesting different D populations for each lineage. The PGLS for Hipparionini was a positive but not significant (p = 0.4912) relationship between D and occlusal surface area, but the relationship for Equini was significantly negative (p = 0.0177). λ was 0 for both tests, indicating no important phylogenetic signal is present in the relationship between these two characters, thus the PGLS collapses down to a non-phylogenetic generalized least squares (GLS) model. The t-test comparing the slopes of the regressions was not significant, indicating that the two lineages could have the same relationship between D and occlusal surface area. Our results suggest that the two tribes have the same negative relationship between D and occlusal surface area but the Hipparionini are offset to higher values than the Equini. This offset reflects the divergence between the two lineages since their last common ancestor and may have constrained their ability to respond to environmental change over the Neogene, leading to the differential survival of the Equini. PMID:27441119

  11. Virtual endocranial cast of earliest Eocene Diacodexis (Artiodactyla, Mammalia) and morphological diversity of early artiodactyl brains.

    PubMed

    Orliac, M J; Gilissen, E

    2012-09-22

    The study of brain evolution, particularly that of the neocortex, is of primary interest because it directly relates to how behavioural variations arose both between and within mammalian groups. Artiodactyla is one of the most diverse mammalian clades. However, the first 10 Myr of their brain evolution has remained undocumented so far. Here, we used high-resolution X-ray computed tomography to investigate the endocranial cast of Diacodexis ilicis of earliest Eocene age. Its virtual reconstruction provides unprecedented access to both metric parameters and fine anatomy of the most complete endocast of the earliest artiodactyl. This picture is assessed in a broad comparative context by reconstructing endocasts of 14 other Early and Middle Eocene representatives of basal artiodactyls, allowing the tracking of the neocortical structure of artiodactyls back to its simplest pattern. We show that the earliest artiodactyls share a simple neocortical pattern, so far never observed in other ungulates, with an almond-shaped gyrus instead of parallel sulci as previously hypothesized. Our results demonstrate that artiodactyls experienced a tardy pulse of encephalization during the Late Neogene, well after the onset of cortical complexity increase. Comparisons with Eocene perissodactyls show that the latter reached a high level of cortical complexity earlier than the artiodactyls.

  12. Peltephilidae and Mesotheriidae (Mammalia) from late Miocene strata of Northern Chilean Andes, Caragua

    NASA Astrophysics Data System (ADS)

    Montoya-Sanhueza, Germán; Moreno, Karen; Bobe, René; Carrano, Matthew T.; García, Marcelo; Corgne, Alexandre

    2017-04-01

    Until now, only one Cenozoic fossil mammal from the Chilean Precordillera (Arica and Parinacota Region) has been reported, Caraguatypotherium munozi (Mesotheriidae: Notoungulata). In this study, we describe a fourth specimen of C. munozi and a new armadillo species, Epipeltephilus caraguensis (Peltephilidae: Cingulata), both collected from a new site closer to the fossiliferous outcrops of the Caragua area (Serravallian - Tortonian). E. caraguensis differs from other members of the family in having: two sulci in the articular surface of the mobile osteoderm; having a tubular, rough and raised anterior edge; a conspicuous transverse depression; and four widely spaced foramina. This taxon represents the youngest known peltephilid from intermediate latitudes and indicates a wide geographic distribution (Patagonia to Central Andes) of the family just prior to its extinction. The new mesothere specimen is 19% larger than previous records. The revision of the dental features of C. munozi allowed the identification of an ambiguous trait in its original diagnosis, i.e. an enamel fracture was misinterpreted with the presence of a posterior sulcus on the talonid of the m3, suggesting that further taxonomic and systematic revision for the Caragua mesothere is necessary. Although the fossil record from the Caragua area is still scarce, mesotheriines seem to be abundant at this latitude, just as has been observed at several early to late Miocene sites such as Chucal (Chile), Cerdas and Nazareno (Bolivia), as well as in southern regions such as Arroyo Chasicó and Mendoza (Argentina). The presence of a new peltephilid species in Caragua sustains the hypothesis of provincialism during the Miocene in intermediate latitudes. Our findings also provide further support for probable faunal movements between intermediate and higher latitudes rather than to lower ones.

  13. Systematics and Evolution of the Miocene Three-Horned Palaeomerycid Ruminants (Mammalia, Ceta