16 CFR 300.19 - Use of terms “mohair” and “cashmere.”

Code of Federal Regulations, 2010 CFR

2010-01-01

... “mohair” and “cashmere.” (a) In setting forth the required fiber content of a product containing hair of the Angora goat known as mohair or containing hair or fleece of the Cashmere goat known as cashmere...

16 CFR 300.19 - Use of terms “mohair” and “cashmere.”

Code of Federal Regulations, 2013 CFR

2013-01-01

... “mohair” and “cashmere.” (a) In setting forth the required fiber content of a product containing hair of the Angora goat known as mohair or containing hair or fleece of the Cashmere goat known as cashmere...

16 CFR 300.19 - Use of terms “mohair” and “cashmere.”

Code of Federal Regulations, 2012 CFR

2012-01-01

... “mohair” and “cashmere.” (a) In setting forth the required fiber content of a product containing hair of the Angora goat known as mohair or containing hair or fleece of the Cashmere goat known as cashmere...

16 CFR 300.19 - Use of terms “mohair” and “cashmere.”

Code of Federal Regulations, 2011 CFR

2011-01-01

... “mohair” and “cashmere.” (a) In setting forth the required fiber content of a product containing hair of the Angora goat known as mohair or containing hair or fleece of the Cashmere goat known as cashmere...

In search of the Golden Fleece: Unraveling principles of morphogenesis by studying the integrative biology of skin appendages

PubMed Central

Hughes, Michael W.; Wu, Ping; Jiang, Ting-Xin; Lin, Sung-Jan; Dong, Chen-Yuan; Li, Ang; Hsieh, Fon-Jou; Widelitz, Randall B.; Choung, Cheng Ming

2013-01-01

Summary The mythological story of the Golden Fleece symbolizes the magical regenerative power of skin appendages. Similar to the adventurous pursuit of the Golden Fleece by the multi-talented Argonauts, today we also need an integrated multi-disciplined approach to understand the cellular and molecular processes during development, regeneration and evolution of skin appendages. To this end, we have explored several aspects of skin appendage biology that contribute to the Turing activator / inhibitor model in feather pattern formation, the topo-biological arrangement of stem cells in organ shape determination, the macro-environmental regulation of stem cells in regenerative hair waves, and potential novel molecular pathways in the morphological evolution of feathers. Here we show our current integrative biology efforts to unravel the complex cellular behavior in patterning stem cells and the control of regional specificity in skin appendages. We use feather / scale tissue recombination to demonstrate the timing control of competence and inducibility. Feathers from different body regions are used to study skin regional specificity. Bioinformatic analyses of transcriptome microarrays show the potential involvement of candidate molecular pathways. We further show Hox genes exhibit some region specific expression patterns. To visualize real time events, we applied time-lapse movies, confocal microscopy and multiphoton microscopy to analyze the morphogenesis of cultured embryonic chicken skin explants. These modern imaging technologies reveal unexpectedly complex cellular flow and organization of extracellular matrix molecules in three dimensions. While these approaches are in preliminary stages, this perspective highlights the challenges we face and new integrative tools we will use. Future work will follow these leads to develop a systems biology view and understanding in the morphogenetic principles that govern the development and regeneration of ectodermal organs. PMID:21437328

Preservation of Facial Nerve Function Repaired by Using Fibrin Glue-Coated Collagen Fleece for a Totally Transected Facial Nerve during Vestibular Schwannoma Surgery

PubMed Central

Choi, Kyung-Sik; Kim, Min-Su; Jang, Sung-Ho

2014-01-01

Recently, the increasing rates of facial nerve preservation after vestibular schwannoma (VS) surgery have been achieved. However, the management of a partially or completely damaged facial nerve remains an important issue. The authors report a patient who was had a good recovery after a facial nerve reconstruction using fibrin glue-coated collagen fleece for a totally transected facial nerve during VS surgery. And, we verifed the anatomical preservation and functional outcome of the facial nerve with postoperative diffusion tensor (DT) imaging facial nerve tractography, electroneurography (ENoG) and House-Brackmann (HB) grade. DT imaging tractography at the 3rd postoperative day revealed preservation of facial nerve. And facial nerve degeneration ratio was 94.1% at 7th postoperative day ENoG. At postoperative 3 months and 1 year follow-up examination with DT imaging facial nerve tractography and ENoG, good results for facial nerve function were observed. PMID:25024825

The Physical Effects of Contact and Close-Distance Gunfire on Sweatshirt Fleece.

PubMed

Kusluski, Michael A

2018-05-01

Powder stippling caused by the impact of propellant particles during close-distance gunfire has been previously described on skin and solid objects only. Additionally, radial tearing has been described as clear evidence of a contact-distance shot, requiring no further testing. Patterns of discrete perforating holes (referred to here as "stippling perforations") and other physical damage on sweatshirt fleece fabrics were prepared. Using the firearm and ammunition in this study, stippling perforations were observed to a maximum muzzle-to-target distance of 35 cm (10 inches). In addition, radial tearing and disintegration were present (and often more extensive) at greater than contact distance. The presence of stippling perforations could augment muzzle-to-target distance estimates generated using the Griess test, or allow distance estimates when the Griess test is not feasible. Unlike what has been previously reported, testing on the original evidence (or similar substitute) is warranted when physical damage is used to estimate shooting distance. © 2017 American Academy of Forensic Sciences.

Anti-flammable properties of cotton fabrics using eco friendly inorganic materials by layering self-assisted processing

USDA-ARS?s Scientific Manuscript database

A flame retardant surface has been prepared by the layer-by layer assemblies of branched polyethylenimine (BPEI), kaolin, urea, diammonium phosphate (dibasic) on cotton fabrics. Four different kinds of cotton fabrics (print cloth, mercerized print cloth, mercerized twill, and fleece) were prepared ...

76 FR 49453 - CVS Pharmacy, Inc., Provisional Acceptance of a Settlement Agreement and Order

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-10

...; telephone (301) 504-7612. SUPPLEMENTARY INFORMATION: The text of the Agreement and Order appears below... hooded fleece jackets with drawstrings at the neck (``Jackets''). 5. CVS sold the Jackets, and/or held... (``Guidelines'') to help prevent children from strangling or entangling on neck and waist drawstrings. The...

High follicle density does not decrease sweat gland density in Huacaya alpacas.

PubMed

Moore, K E; Maloney, S K; Blache, D

2015-01-01

When exposed to high ambient temperatures, mammals lose heat evaporatively by either sweating from glands in the skin or by respiratory panting. Like other camelids, alpacas are thought to evaporate more water by sweating than panting, despite a thick fleece, unlike sheep which mostly pant in response to heat stress. Alpacas were brought to Australia to develop an alternative fibre industry to sheep wool. In Australia, alpacas can be exposed to ambient temperatures higher than in their native South America. As a young industry there is a great deal of variation in the quality and quantity of the fleece produced in the national flock. There is selection pressure towards animals with finer and denser fleeces. Because the fibre from secondary follicles is finer than that from primary follicles, selecting for finer fibres might alter the ratio of primary and secondary follicles. In turn the selection might alter sweat gland density because the sweat glands are associated with the primary follicle. Skin biopsy and fibre samples were obtained from the mid-section of 33 Huacaya alpacas and the skin sections were processed into horizontal sections at the sebaceous gland level. Total, primary, and secondary follicles and the number of sweat gland ducts were quantified. Fibre samples from each alpaca were further analysed for mean fibre diameter. The finer-fibred animals had a higher total follicle density (P<0.001) and more sweat glands (P<0.001) than the thicker-fibred animals. The fibre diameter and total follicle density were negatively correlated (R(2)=0.56, P<0.001). Given that the finer-fibred animals had higher follicle density and more sweat glands than animals with thicker fibres, we conclude that alpacas with high follicle density should not be limited for potential sweating ability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Aries

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

(the Ram; abbrev. Ari, gen. Arietis; area 441 sq. deg.) A northern zodiacal constellation that lies between Taurus and Pisces, and culminates at midnight in late October. It represents the ram in Greek mythology whose golden fleece was the quest of Jason and the Argonauts. Its brightest stars were cataloged by Ptolemy (c. AD 100-175) in the Almagest. In Ptolemy's day the Sun was in Aries at the v...

The Genetic Inheritance of the Blue-eyed White Phenotype in Alpacas (Vicugna pacos)

PubMed Central

Johnson, Warren E.; Appleton, Belinda R.

2014-01-01

White-spotting patterns in mammals can be caused by mutations in the gene KIT, whose protein is necessary for the normal migration and survival of melanocytes from the neural crest. The alpaca (Vicugna pacos) blue-eyed white (BEW) phenotype is characterized by 2 blue eyes and a solid white coat over the whole body. Breeders hypothesize that the BEW phenotype in alpacas is caused by the combination of the gene causing gray fleece and a white-spotting gene. We performed an association study using KIT flanking and intragenic markers with 40 unrelated alpacas, of which 17 were BEW. Two microsatellite alleles at KIT-related markers were significantly associated (P < 0.0001) with the BEW phenotype (bew1 and bew2). In a larger cohort of 171 related individuals, we identify an abundance of an allele (bew1) in gray animals and the occurrence of bew2 homozygotes that are solid white with pigmented eyes. Association tests accounting for population structure and familial relatedness are consistent with a proposed model where these alleles are in linkage disequilibrium with a mutation or mutations that contribute to the BEW phenotype and to individual differences in fleece color. PMID:23144493

Effect of sex and rearing system on the quality and mineral content of fiber from raeini cashmere goats

PubMed Central

2012-01-01

The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 μm, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05). PMID:22958733

[Suitability of Bacillus subtilis and Bacillus stearothermophilus spores as test organism bioindicators for detecting superheating of steam].

PubMed

Spicher, G; Peters, J

1997-02-01

Biological indicators used to test sterilisation procedures for their efficacy consist of a so-called germ carrier to which the microorganisms used as test organisms adhere. In previous papers we demonstrated that carriers made of filter paper on contact with saturated steam show superheating while carriers made of glass fibre fleece as well as wetted filter paper do not. Using spores of Bacillus subtilis and Bacillus stearothermophilus as test organisms we have now investigated whether and to what extent carrier superheating affects the characteristic values (t50%) of these biological indicators. The indicators were exposed to saturated steam at 100 degrees C (B. subtilis) or 120 degrees C (B. stearothermophilus) under three different exposure conditions: 1. dry (i.e. conditioned to 45% relative humidity before introduction into the sterilising chamber), freely accessible; 2. dry with a substratum and a cover of filter card-board; 3. wet (moistened with twice distilled water before introduction into the sterilising chamber), freely accessible. For previously selected exposure periods, the incidence of indicators with surviving test organisms was determined. The reaction pattern of bioindicators with spores of B. stearothermophilus was different from that of bioindicators with spores of B. subtilis. For B. subtilis, the incidence of bioindicators exhibiting surviving test organisms depended on the nature of the carries as well as on the exposure conditions. On filter paper carriers, t50% increased in the order "wet, freely accessible", "dry, freely accessible", "dry, between filter card-board". On dry and wetted glass fibre fleece, resistance was approximately the same; when the indicators were sandwiched between layers of filter card-board, t50% increased. For B. stearothermophilus, t50% was largely dependent on the carrier material alone. The values obtained for filter paper were invariably much lower than those for glass fibre fleece. As the results show, using spores of B. subtilis it is possible to detect superheating, but the steam resistance of the spores is relatively low. Spores of B. stearothermophilus are of high steam resistance but they are practically unsuitable for detecting superheating. It is imperative to search for a test organism the resistance of which against steam is sufficiently high and which at the same time is capable of reacting to superheating (equivalent to reduced humidity) by a sufficiently large increase in resistance.

Soviet Union, Military Affairs.

DTIC Science & Technology

1987-06-05

Above the Pripyat 17, 19 Yangazov, V. The Golden Fleece of the Hero 12 SONGS Far from Port. Music by M. Kochetova, words by A. Matyushkin-Gerke...13 Great Party. Music by B. Terentyev, Words by M. Karamushko 4 No Going on a March Without a Song. Music by L. Lyadova, words by V. Sokolov 20...Lenin Hills. Music by M. Protasov, words by V. Goncharov 7 38 Military Conductors. Music by B. Figotin, words.by F. Laube.. ...v... 12 Roads. Music

Microfiber Masses Recovered from Conventional Machine Washing of New or Aged Garments.

PubMed

Hartline, Niko L; Bruce, Nicholas J; Karba, Stephanie N; Ruff, Elizabeth O; Sonar, Shreya U; Holden, Patricia A

2016-11-01

Synthetic textiles can shed numerous microfibers during conventional washing, but evaluating environmental consequences as well as source-control strategies requires understanding mass releases. Polyester apparel accounts for a large proportion of the polyester market, and synthetic jackets represent the broadest range in apparel construction, allowing for potential changes in manufacturing as a mitigation measure to reduce microfiber release during laundering. Here, detergent-free washing experiments were conducted and replicated in both front- and top-load conventional home machines for five new and mechanically aged jackets or sweaters: four from one name-brand clothing manufacturer (three majority polyester fleece, and one nylon shell with nonwoven polyester insulation) and one off-brand (100% polyester fleece). Wash water was filtered to recover two size fractions (>333 μm and between 20 and 333 μm); filters were then imaged, and microfiber masses were calculated. Across all treatments, the recovered microfiber mass per garment ranged from approximately 0 to 2 g, or exceeding 0.3% of the unwashed garment mass. Microfiber masses from top-load machines were approximately 7 times those from front-load machines; garments mechanically aged via a 24 h continuous wash had increased mass release under the same wash protocol as new garments. When published wastewater treatment plant influent characterization and microfiber removal studies are considered, washing synthetic jackets or sweaters as per this study would account for most microfibers entering the environment.

Improvement of the tissue-adhesive and sealing effect of fibrin sealant using polyglycolic acid felt.

PubMed

Shinya, Noriko; Oka, Shirou; Miyabashira, Sumika; Kaetsu, Hiroshi; Uchida, Takanori; Sueyoshi, Masuo; Takase, Kozo; Akuzawa, Masao; Miyamoto, Atsushi; Shigaki, Takamichi

2009-01-01

Although fibrin sealant (FS) has an advantage of high biocompatibility, its adhesive force and sealing effect have been generally considered to be inadequate. In the present study, a high adhesive force and sealing effect were obtained by first rubbing fibrinogen solution into the target tissue, attaching polyglycolic acid (PGA) felt to the treated area, and finally spraying it with FS. This method was compared with three conventional FS application methods and a method using fibrin glue-coated collagen fleece. The adhesive force resulting from the present method was 12 times higher than that for the sequential application method, 4.5 times higher than the spray method, 2.5 times higher than the rubbing and spray method, and 2.2 times higher than the use of fibrin glue-coated collagen fleece. The high adhesive force of FS with PGA felt seemed to be due the high fibrin content of the fibrin gel (FG). Light and electron microscopic observations suggested that the formation of FG in closer contact with the muscle fibers was a factor contributing to this superior adhesive force. Comparison of the sealing effect of the present method with other methods using various biomaterials in combination with FS showed that the sealing effect of FS with PGA felt was 1.4 times higher that of polyglactin 910, 1.8 times that of polytetrafluoroethylene, and 6.7 times that of oxidized regenerated cellulose.

Two fossil species of Metrosideros (Myrtaceae) from the Oligo-Miocene Golden Fleece locality in Tasmania, Australia.

PubMed

Tarran, Myall; Wilson, Peter G; Macphail, Michael K; Jordan, Greg J; Hill, Robert S

2017-06-01

The capsular-fruited genus Metrosideros (Myrtaceae) is one of the most widely distributed flowering plant genera in the Pacific but is extinct in Australia today. The center of geographic origin for the genus and the reason for and timing of its extinction in Australia remain uncertain. We identify fossil Metrosideros fruits from the newly discovered Golden Fleece fossil flora in the Oligo-Miocene of Tasmania, Australia, shedding further light on these problems. Standard paleopalynological techniques were used to date the fossil-bearing sediments. Scanning electron microscopy and an auto-montage camera system were used to take high-resolution images of fossil and extant fruits taken from herbarium specimens. Fossils are identified using a nearest-living-relative approach. The fossil-bearing sediments are palynostratigraphically dated as being Proteacidites tuberculatus Zone Equivalent (ca. 33-16 Ma) in age and provide a confident Oligo-Miocene age for the macrofossils. Two new fossil species of Metrosideros are described and are here named Metrosideros dawsonii sp. nov. and Metrosideros wrightii sp. nov. These newly described fossil species of Metrosideros provide a second record of the genus in the Cenozoic of Australia, placing them in the late Early Oligocene to late Early Miocene. It is now apparent not only that Metrosideros was present in Australia, where the genus is now extinct, but that at least several Metrosideros species were present during the Cenozoic. These fossils further strengthen the case for an Australian origin of the genus. © 2017 Botanical Society of America.

Dynamics of house dust mite transfer in modern clothing fabrics.

PubMed

Clarke, David; Burke, Daniel; Gormally, Michael; Byrne, Miriam

2015-04-01

Clothing is largely presumed as being the mechanism by which house dust mites are distributed among locations in homes, yet little research to date has investigated the capacity with which various clothing fabric types serve as vectors for their accumulation and dispersal. Although previous research has indicated that car seats provide a habitat for mite populations, dynamics involved in the transfer of mites to clothing via car seat material is still unknown. To investigate the dynamics involved in the transfer of house dust mites from car seat material to modern clothing fabrics. A total of 480 samples of car seat material were seeded with mites and subjected to contact with plain woven cotton, denim, and fleece. Contact forces equivalent to the mass of a typical adult and child were administered for different durations of contact. Mean transfer efficiencies of mites from car seat material to receiving clothing fabrics ranged from 7.2% to 19.1%. Fabric type, mite condition (live or dead), and the force applied all revealed a significant effect (P < .001 for each variable) on the transfer efficiency of house dust mites from seeded material to receiving fabrics, whereas duration of contact revealed no effect (P = .20). In particular, mean numbers of mites transferred to fleece (compared with denim and plain woven cotton) were greater for each treatment. These findings indicate that clothing type can have important implications for the colonization of other biotopes by house dust mites, with potential for affecting an individuals' personal exposure to dust mite allergens. Copyright © 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Clinical appraisal of arterial stiffness: the Argonauts in front of the Golden Fleece

PubMed Central

Vlachopoulos, C; Aznaouridis, K; Stefanadis, C

2006-01-01

Interest in evaluating arterial elastic properties has grown in parallel with the widespread availability of non‐invasive methods for assessing arterial stiffness. A clinically useful diagnostic index must be pathophysiologically relevant, must be readily measurable, and must indicate the severity of the disease and predict the corresponding risk. Interventional modification of this index must parallel disease regression and benefit prognosis. The current evidence for the clinical value of estimating arterial stiffness (mainly of large, elastic‐type arteries, such as the aorta and the carotids) in the contemporary era of cardiovascular medicine is reviewed. PMID:16339817

Genetic correlations among and between wool, growth and reproduction traits in Merino sheep.

PubMed

Safari, E; Fogarty, N M; Gilmour, A R; Atkins, K D; Mortimer, S I; Swan, A A; Brien, F D; Greeff, J C; van der Werf, J H J

2007-04-01

Data from seven research resource flocks across Australia were combined to provide accurate estimates of genetic correlations among production traits in Merino sheep. The flocks represented contemporary Australian Merino fine, medium and broad wool strains over the past 30 years. Over 110,000 records were available for analysis for each of the major wool traits, and 50,000 records for reproduction and growth traits with over 2700 sires and 25,000 dams. Individual models developed from the single trait analyses were extended to the various combinations of two-trait models to obtain genetic correlations among six wool traits [clean fleece weight (CFW), greasy fleece weight, fibre diameter (FD), yield, coefficient of variation of fibre diameter and standard deviation of fibre diameter], four growth traits [birth weight, weaning weight, yearling weight (YWT), and hogget weight] and four reproduction traits [fertility, litter size, lambs born per ewe joined, lambs weaned per ewe joined (LW/EJ)]. This study has provided for the first time a comprehensive matrix of genetic correlations among these 14 wool, growth and reproduction traits. The large size of the data set has also provided estimates with very low standard errors. A moderate positive genetic correlation was observed between CFW and FD (0.29 +/- 0.02). YWT was positively correlated with CFW (0.23 +/- 0.04), FD (0.17 +/- 0.04) and LWEJ (0.58 +/- 0.06), while LW/EJ was negatively correlated with CFW (-0.26 +/- 0.05) and positively correlated with FD (0.06 +/- 0.04) and LS (0.68 +/- 0.04). These genetic correlations, together with the estimates of heritability and other parameters provide the basis for more accurate prediction of outcomes in complex sheep-breeding programmes designed to improve several traits.

Convective and radiative components of wind chill in sheep: Estimation from meteorological records

NASA Astrophysics Data System (ADS)

Brown, D.; Mount, L. E.

1987-06-01

Wind chill is defined as the excess of sensible heat loss over what would occur at zero wind speed with other conditions unchanged. Wind chill can be broken down into a part that is determined by air temperature and a radiative part that comprises wind-dependent effects on additional long-wave radiative exchange and on solar radiation (by reducing solar warming). Radiative exchange and gain from solar radiation are affected by changes that are produced by wind in both surface and fleece insulations. Coefficients are derived for (a) converting the components of sensible heat exchange (air-temperature-dependent including both convective and associated long-wave radiative, additional long-wave radiative and solar) into the components of the total heat loss that are associated with wind and (b) for calculating equivalent air temperature changes. The coefficients contain terms only in wind speed, wetting of the fleece and fleece depth; these determine the external insulation. Calculation from standard meteorological records, using Plymouth and Aberdeen in 1973 as examples, indicate that in April September 1973 at Plymouth reduction in effective solar warming constituted 28% of the 24-h total wind chill, and 7% in the other months of the year combined; at Aberdeen the corresponding percentages were 25% and 6%. Mean hour-of-day estimates for the months of April and October showed that at midday reduction in solar warming due to wind rose to the order of half the air-temperature-dependent component of wind chill, with a much smaller effect in January. For about six hours at midday in July reduction in solar warming due to wind was similar in magnitude to the air-temperature-dependent component. It is concluded that realistic estimates of wind chill cannot be obtained unless the effect of solar radiation is taken into account. Failure to include solar radiation results not only in omitting solar warming but also in omitting the effects of wind in reducing that warming. The exchange of sensible (non-evaporative) heat loss between a homeothermic animal and its environment can be divided into two parts: one part is due to the temperature difference between the animal and the surrounding air, and the other part is due to additional long-wave radiative exchange between animal and environment and to solar radiation. Both parts of the heat exchange are determined in magnitude by the animal's thermal insulation, which is itself affected by windspeed and wetting. Wind diminishes as animal's external insulation, so increasing heat loss under all conditions when the air temperature is lower than the animal's surface temperature: this effect is termed wind chill. Wind chill has previously been investigated more commonly in relation to man (Burton an Edholm, 1955; Smithson and Baldwin, 1978; Mumford, 1979; Baldwin and Smithson, 1979). This paper is concerned with the separate contributions to wind chill calculated for sheep that can be associated with convective and radiative heat exchanges.

High-Altitude Hydration System

NASA Technical Reports Server (NTRS)

Parazynski, Scott E.; Orndoff, Evelyne; Bue, Grant C.; Schaefbauer, Mark E.; Urban, Kase

2010-01-01

Three methods are being developed for keeping water from freezing during high-altitude climbs so that mountaineers can remain hydrated. Three strategies have been developed. At the time of this reporting two needed to be tested in the field and one was conceptual. The first method is Passive Thermal Control Using Aerogels. This involves mounting the fluid reservoir of the climber s canteen to an inner layer of clothing for better heat retention. For the field test, bottles were mounted to the inner fleece layer of clothing, and then aerogel insulation was placed on the outside of the bottle, and circumferentially around the drink straw. When climbers need to drink, they can pull up the insulated straw from underneath the down suit, take a sip, and then put it back into the relative warmth of the suit. For the field test, a data logger assessed the temperatures of the water reservoir, as well as near the tip of the drink straw. The second method is Passive Thermal Control with Copper-Shielded Drink Straw and Aerogels, also mounted to inner layers of clothing for better heat retention. Braided wire emanates from the inside of the fleece jacket layer, and continues up and around the drink straw in order to use body heat to keep the system-critical drink straw warm enough to keep water in the liquid state. For the field test, a data logger will be used to compare this with the above concept. The third, and still conceptual, method is Active Thermal Control with Microcontroller. If the above methods do not work, microcontrollers and tape heaters have been identified that could keep the drink straw warm even under extremely cold conditions. Power requirements are not yet determined because the thermal environment inside the down suit relative to the external environment has not been established. A data logger will be used to track both the external and internal temperatures of the suit on a summit day.

Sources of psychrophilic and psychrotolerant clostridia causing spoilage of vacuum-packed chilled meats, as determined by PCR amplification procedure.

PubMed

Broda, D M; Boerema, J A; Brightwell, G

2009-07-01

To determine possible preslaughter and processing sources of psychrophilic and psychrotolerant clostridia causing spoilage of vacuum-packed chilled meats. Molecular methods based on the polymerase chain reaction (PCR) amplification of specific 16S rDNA fragments were used to detect the presence of Clostridium gasigenes, Clostridium estertheticum, Clostridium algidicarnis and Clostridium putrefaciens in a total of 357 samples collected from ten slaughter stock supply farms, slaughter stock, two lamb-processing plants, their environments, dressed carcasses and final vacuum-packed meat stored at -0.5 degrees C for 5(1/2) weeks. Clostridium gasigenes, C. estertheticum and C. algidicarnis/C. putrefaciens were commonly detected in farm, faeces, fleece and processing environmental samples collected at the slaughter floor operations prior to fleece removal, but all these micro-organisms were detected in only 4 out of 26 cooling floor and chiller environmental samples. One out of 42 boning room environmental samples tested positive for the presence of C. gasigenes and C. estertheticum, but 25 out of 42 of these samples were positive for C. algidicarnis/C. putrefaciens. Nearly all of the 31 faecal samples tested positive for the presence of C. gasigenes and C. estertheticum; however, only two of these samples were positive for C. algidicarnis and/or C. putrefaciens. Clostridial species that were subject to this investigation were frequently detected on chilled dressed carcasses. The major qualitative and quantitative differences between the results of PCR detection obtained with the primers specific for 'blown pack' -causing clostridia (C. gasigenes and C. estertheticum) and those obtained with primers specific for C. algidicarnis and C. putrefaciens suggest that the control of meat spoilage caused by different groups of meat clostridia is best approached individually for each group. This paper provides information significant for controlling meat spoilage-causing clostridia in the meat-processing plants.

Surface changes of enamel after brushing with charcoal toothpaste

NASA Astrophysics Data System (ADS)

Pertiwi, U. I.; Eriwati, Y. K.; Irawan, B.

2017-08-01

The aim of this study was to determine the surface roughness changes of tooth enamel after brushing with charcoal toothpaste. Thirty specimens were brushed using distilled water (the first group), Strong® Formula toothpaste (the second group), and Charcoal® Formula toothpaste for four minutes and 40 seconds (equivalent to one month) and for 14 minutes (equivalent to three months) using a soft fleece toothbrush with a mass of 150 gr. The roughness was measured using a surface roughness tester, and the results were tested with repeated ANOVA test and one-way ANOVA. The value of the surface roughness of tooth enamel was significantly different (p<0.05) after brushing for an equivalent of one month and an equivalent of three months. Using toothpaste containing charcoal can increase the surface roughness of tooth enamel.

Periphyton accumulation at remote reefs and shoals in Lake Superior

USGS Publications Warehouse

Edsall, Thomas A.; Stoermer, Eugene F.; Kociolek, John P.

1991-01-01

Observations made from a submarine showed that the bed-rock surfaces at water depths of about 5 to 14 m on Stannard Rock and Superior Shoal in Lake Superior were covered with a dense, fleece-like blanket of periphyton. Examination of the periphyton revealed it consisted primarily of structurally complex, diverse, diatom communities, but occasional small thalli of the green algae Cladophora andStigeoclonium were also noted. Extensive windrows of detritus-like material, apparently derived from the local periphyton community, were seen on soft bottoms at depths of about 20 to 60 m near the reefs. Our observations suggested that these periphyton communities may be locally important to the food web at these remote and oligotrophic sites, which are 22 to 77 km from the nearest mainland shore and are surrounded by water at least 140 m deep.

Flexible ultra-wideband antenna incorporated with metamaterial structures: multiple notches for chipless RFID application

NASA Astrophysics Data System (ADS)

Jalil, M. E.; Rahim, M. K. A.; Samsuri, N. A.; Dewan, R.; Kamardin, K.

2017-01-01

A coplanar waveguide (CPW) ultra-wideband (UWB) antenna incorporated with metamaterial—split ring resonator structure—that operates from 3.0 to 12.0 GHz is proposed for chipless RFID tag. The 30 mm × 40 mm flexible chipless RFID tag is designed on the fleece substrate ( ɛ r = 1.35, thickness = 1 mm and tan δ = 0.025). A six-slotted modified complementary split ring resonator (MCSRR) is introduced into the ultra-wideband antenna to produce multiple band notches at 3.0, 4.0, 5.0, 6.0 and 7.0 GHz. The frequency shifting technique is introduced for designing a high-capacity chipless RFID tag with compact size. Each MCSRR is able to code in four different allocations (00, 01, 10 and 11). To achieve encoding of 10-bits data (10,234 number), six MCSRRs are proposed with three-slotted MCSRR in the radiator and three-slotted MCSRR in the ground plane.

Genetic parameters for wool traits, live weight, and ultrasound carcass traits in Merino sheep.

PubMed

Mortimer, S I; Hatcher, S; Fogarty, N M; van der Werf, J H J; Brown, D J; Swan, A A; Greeff, J C; Refshauge, G; Edwards, J E Hocking; Gaunt, G M

2017-05-01

Genetic correlations between 29 wool production and quality traits and live weight and ultrasound fat depth (FAT) and eye muscle depth (EMD) traits were estimated from the Information Nucleus (IN). The IN comprised 8 genetically linked flocks managed across a range of Australian sheep production environments. The data were from a maximum of 9,135 progeny born over 5 yr from 184 Merino sires and 4,614 Merino dams. The wool traits included records for yearling and adult fleece weight, fiber diameter (FD), staple length (SL), fiber diameter CV (FDCV), scoured color, and visual scores for breech and body wrinkle. We found high heritability for the major yearling wool production traits and some wool quality traits, whereas other wool quality traits, wool color, and visual traits were moderately heritable. The estimates of heritability for live weight generally increased with age as maternal effects declined. Estimates of heritability for the ultrasound traits were also higher when measured at yearling age rather than at postweaning age. The genetic correlations for fleece weight with live weights were positive (favorable) and moderate (approximately 0.5 ± 0.1), whereas those with FD were approximately 0.3 (unfavorable). The other wool traits had lower genetic correlations with the live weights. The genetic correlations for FAT and EMD with FD and SL were positive and low, with FDCV low to moderate negative, but variable with wool weight and negligible for the other wool traits. The genetic correlations for FAT and EMD with postweaning weight were positive and high (0.61 ± 0.18 to 0.75 ± 0.14) but were generally moderate with weights at other ages. Selection for increased live weight will result in a moderate correlated increase in wool weight as well as favorable reductions in breech cover and wrinkle, along with some unfavorable increases in FD and wool yellowness but little impact on other wool traits. The ultrasound meat traits, FAT and EMD, were highly positively genetically correlated (0.8), and selection to increase them would result in a small unfavorable correlated increase in FD, moderately favorable reductions in breech cover and wrinkle, but equivocal or negligible changes in other wool traits. The estimated parameters provide the basis for calculation of more accurate Australian Sheep Breeding Values and selection indexes that combine wool and meat objectives in Merino breeding programs.

Breeding objectives for Targhee sheep.

PubMed

Borg, R C; Notter, D R; Kuehn, L A; Kott, R W

2007-11-01

Breeding objectives were developed for Targhee sheep under rangeland production conditions. Traits considered were those for which EPD were available from the US National Sheep Improvement Program and included direct and maternal effects on 120-d weaning weight (WW and MM, respectively); yearling weight (YW); yearling fleece weight, fiber diameter, and staple length; and percent lamb crop (PLC), measured as the number of lambs born per 100 ewes lambing. A bioeconomic model was used to predict the effects of a change of 1 additive SD in EPD for each trait, holding all other traits constant at their mean, on animal performance, feed requirements, feed costs, and economic returns. Resulting economic weightings were then used to derive selection indexes. Indexes were derived separately for 3 prolificacy levels (1.41, 1.55, and 1.70 lambs/ewe lambing), 2 triplet survival levels (50 and 67%), 2 lamb pricing policies (with or without discounting of prices for heavy feeder lambs), and 3 forage cost scenarios (renting pasture, purchasing hay, or reducing flock size to accommodate increased nutrient requirements for production). Increasing PLC generally had the largest impact on profitability, although an increase in WW was equally important, with low feed costs and no discounting of prices for heavy feeder lambs. Increases in PLC were recommended at all 3 prolificacy levels, but with low triplet survival the value of increasing PLC eventually declined as the mean litter size increased to approximately 2.15 lambs/ewe lambing and above. Increasing YW (independent of WW) increased ewe maintenance costs and reduced profitability. Predicted changes in breeding values for WW and YW under index selection varied with lamb pricing policy and feed costs. With low feed costs or no discounts for heavy lambs, YW increased at a modest rate in association with increasing WW, but with high feed costs or discounting of heavy lambs, genetic trends in WW were reduced by approximately 50% to constrain increases in YW. Changes in EPD for MM or fleece traits generally had smaller effects on profitability than changes in PLC, WW, and YW. Two indexes designed to address current rangeland production conditions (low forage costs and discounting of heavy feeder lambs) or more intensive and integrated production with retained ownership and value-based marketing of lambs (higher forage costs and no discounting of heavy lambs) were anticipated to meet the needs of most Targhee producers.

The response of shoot accumulation of trace elements in Chinese cabbage to microclimate modification.

PubMed

Moreno, D A; Villora, M G; Hernández, J; Castilla, N; Romer, L

2001-01-01

In three consecutive years of field experiments (1994-96), three different environmental conditions for the growth of Chinese cabbage (Brassica pekinensis (Lour) Rupr. cv. Nagaoka 50) were established by using two cover treatments (T1 and T2) and a control uncovered cultivation (T0). The T1 [50 microm polyethylene cover; 20 degrees C air temperature; 61.9% relative moisture; 207 Wm(-2) irradiance] and T2 [a 17 gm(-2) non-woven fleece; 18 degrees C; 63.4%; 205 Wm(-2) gave rise to differences in environmental conditions with respect to T0 [14 degrees C; 57.5%; 237 Wm(-2)]. We analysed chloride (Cl), barium (Ba). rubidium (Rb) and tin (Sn) in the whole tops of experimental plants. Chloride removal was high for Brassica pekinensis but considerably lower for Rb, giving intermediate values for Ba and Sn. The influence of environmental factors under T1 increased trace-element removal and enhanced the usefulness for phytoremedation.

Biosensor technology for the detection of illegal drugs I: objectives, preparatory work, and drug enrichment

NASA Astrophysics Data System (ADS)

Hilpert, Reinhold; Binder, Florian; Grol, Michael; Hallermayer, Klaus; Josel, Hans-Peter; Klein, Christian; Maier, Josef; Oberpriller, Helmut; Ritter, Josef; Scheller, Frieder W.

1994-10-01

In a joint project of Deutsche Aerospace, Boehringer Mannheim and the University of Potsdam portable devices for the detection of illegal drugs, based on biosensor technology, are being developed. The concept enrichment of the drug from the gas phase and detection by immunological means. This publication covers the description of our objectives, preparatory work and results concerning enrichment of drugs from the gas phase. Vapor pressures of cocaine and cannabinoids have been determined. A test gas generator has been constructed which allows for reproducible preparation of cocaine concentrations between 2 ng/l and 2 pg/l. Coupling of a thermodesorption unit with GC/MS has been established for reference analysis. As another analytical tool, an ELISA with a lower detection limit of about 0,5 pg cocaine/assay has been developed. Applying fleece-type adsorbers, enrichment factors for cocaine in the range of 105 have been realized. No significant interference was found with potentially disturbing substances.

Quantifying shedding of synthetic fibers from textiles; a source of microplastics released into the environment.

PubMed

Carney Almroth, Bethanie M; Åström, Linn; Roslund, Sofia; Petersson, Hanna; Johansson, Mats; Persson, Nils-Krister

2018-01-01

Microplastics in the environment are a subject of intense research as they pose a potential threat to marine organisms. Plastic fibers from textiles have been indicated as a major source of this type of contaminant, entering the oceans via wastewater and diverse non-point sources. Their presence is also documented in terrestrial samples. In this study, the amount of microfibers shedding from synthetic textiles was measured for three materials (acrylic, nylon, polyester), knit using different gauges and techniques. All textiles were found to shed, but polyester fleece fabrics shed the greatest amounts, averaging 7360 fibers/m -2 /L -1 in one wash, compared with polyester fabrics which shed 87 fibers/m -2 /L -1 . We found that loose textile constructions shed more, as did worn fabrics, and high twist yarns are to be preferred for shed reduction. Since fiber from clothing is a potentially important source of microplastics, we suggest that smarter textile construction, prewashing and vacuum exhaustion at production sites, and use of more efficient filters in household washing machines could help mitigate this problem.

Airborne Salmonella and Listeria associated with Irish commercial beef, sheep and pig plants.

PubMed

Okraszewska-Lasica, Wioletta; Bolton, D J; Sheridan, J J; McDowell, D A

2014-06-01

Air samples from lairage, hide/fleece pulling or dehairing/scraping, evisceration and chilling areas in commercial beef, sheep and pig plants were examined for Salmonella spp. and Listeria monocytogenes, by impaction or sedimentation onto selective (Brilliant Green Agar, BSA; Listeria Selective Agar, LSA) and non-selective (Plate Count Agar, PCA) media. Both pathogens were frequently detected in all three plants. Improved recoveries were achieved by combining sedimentation, and broth based resuscitation, suggesting cell injury. Salmonella were recovered from all three plants, with the highest counts on BGA in the pig plant. The most common serotypes were S. Typhimurium in the beef/sheep plants and S. Derby in the pig plant. Very low counts of L. monocytogenes (e.g. 2.6CFUm(2)) were detected at hide removal on LSA sedimentation plates in the beef plant. These included serogroup 1/2a-3a and 1/2b-3b-7. Pathogen counts in the three plants were generally very low, suggesting that air is unlikely to be a significant source of carcass or plant surface contamination. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Shetland Islands scrapie monitoring and control programme: analysis of the clinical data collected from 772 scrapie suspects 1985-1997.

PubMed

Cockcroft, P D; Clark, A M

2006-02-01

There were 574 scrapie positive suspects (histopathological scrapie lesions present) and 198 scrapie negative suspects (histopathological scrapie lesions absent). The greatest number of scrapie cases were recorded in sheep of 2, 3 and 4 years of age which represented 17%, 36% and 23% of the scrapie positive suspects, respectively. The sign sensitivities and specificities for the ten recorded signs were, respectively: pruritus (62%, 42%), ataxia (23%, 74%), hyperaesthesia (32%, 74%), wool loss (25%, 73%), fleece discolouration (29%, 85%), bruxism (23%, 69%), nibbling reflex (17%, 58%), head rubbing (47%, 78%), poll rubbing (25%, 83%). These single signs had poor discriminatory values with likelihood ratios close to one (range 0.89-1.21); combinations of the four signs, pruritus, wool loss, ataxia, hyperaesthesia and emaciation were more discriminatory (range 0.30-4.3). This study covered a time period when bovine spongiform encephalopathy (BSE) might have been introduced into the sheep population on the Shetland Islands via contaminated feed. No temporal changes could be detected in the age structure of the affected animals.

Effects of hygienic treatments during slaughtering on microbial dynamics and contamination of sheep meat.

PubMed

Omer, Mohamed K; Hauge, Sigrun J; Østensvik, Øyvin; Moen, Birgitte; Alvseike, Ole; Røtterud, Ole-Johan; Prieto, Miguel; Dommersnes, Sissel; Nesteng, Ole H; Nesbakken, Truls

2015-02-02

The aims of this study were to investigate bacterial dynamics in the sheep meat chain, from fleece to meat trimmings, using both quantitative and qualitative analyses, and to study the effects on microbial load associated with the hygienic interventions of: i) shearing sheep immediately before slaughter, ii) manual steam vacuum pasteurisation, iii) hot water pasteurisation of carcasses, followed by iv) chilling. A further aim was to provide evidence to determine whether or not unshorn sheep should be handled in a processing line separate from that of shorn sheep in Norwegian abattoirs. A total of 176 surface swab samples were collected from three sites along the value chain: i) on fleeces, ii) on carcasses at the end of the slaughter line, and iii) on carcasses after chilling for 24h, and 32 samples were collected from meat trimmings. The results showed that Aerobic Plate Counts (APC) were lower for the shorn group compared to the unshorn group, both on carcasses before chilling and after chilling (difference of 0.8 and 0.9logCFU/1000cm(2) (p≤0.05), respectively) and in meat trimmings (difference of 0.5logCFU/g (p≤0.05)). Hygienic treatments were used on carcasses derived from unshorn sheep, and steam vacuum treatment reduced Escherichia coli, Enterobacteriaceae, and APC before chilling by 1.2, 1.0, and 0.6logCFU/1000cm(2) (p≤0.05), respectively, and hot water pasteurisation, in addition to chilling, reduced E. coli, Enterobacteriaceae, and APC by 0.7, 1.0, and 0.9logCFU/1000cm(2) (p≤0.05), respectively, compared with untreated carcasses. The effect of chilling was shown by the significant reduction of number of carcasses where E. coli were detected; from 65% (13/20) of the shorn group before chilling to 35% (7/20) after chilling, and from 90% (36/40) to 45% (9/20) of the unshorn group. Sequencing of the 16S rRNA gene derived from 316 colonies of Enterobacteriaceae showed a tendency for the relative proportion of the genus Escherichia/Shigella, compared with other genera within Enterobacteriaceae, to be greater for unshorn, untreated sheep than from the other groups at the sampling locations along the meat chain. The study showed that steam vacuum and hot water pasteurisation reduced the contamination of carcasses derived from unshorn sheep, down to the level of the shorn group, and thus can replace the separate processing line for unshorn sheep. Indeed, the low microbial contamination in meat trimmings for all groups indicates that the separate processing line is unnecessary. Copyright © 2014 Elsevier B.V. All rights reserved.

Harmonic curved shears system prevent of bile leakage after liver resection in a pig model.

PubMed

Shimoda, Mitsugi; Iwasaki, Yoshimi; Kubota, Keiichi

2014-01-01

We evaluated the efficacy of TachoComb (TC) collagen fleece and Harmonic Focus (HF) shears in a pig liver resection model. Pigs were divided into 3 groups of 7, in which vessels were tied with silk and TC was applied to the cut surfaces (Silk+TC group), sealed and sheared with HF and TC (HF+TC group), or sealed using HF alone (HF-TC group). After 1 month, we conducted a histologic evaluation and recorded the incidence of bile leakage with infected collections at the liver cut surface. Six pigs were evaluated in each group. In the Silk+TC group, 4 of the 6 pigs had infected collections at the cut surface. Histologically, the silk had remained under the fibrotic tissue, which contained remnants of TC fragments. In the HF+TC group, 5 of the 6 pigs also had infected collections, and histologically, TC had remained in the hard fibrotic tissues. In the HF-TC group, none of the 6 pigs had infected collections, and the histologic findings were normal. Use of the HF alone may be an effective method for preventing bile leakage in infected collections after liver resection.

A pilot study: The effects of repeat washing and fabric type on the detection of seminal fluid and spermatozoa.

PubMed

Nolan, A; Speers, Samuel J; Murakami, Julie; Chapman, Brendan

2018-05-19

In sexual assault cases and more specifically those involving childhood sexual abuse (CSA), victims may have had their potentially semen-stained clothing washed multiple times before a criminal investigation commences. Although it has been previously demonstrated that spermatozoa persist on cotton clothing following a single wash cycle, items of clothing washed multiple times are not routinely examined in these cases because of the assumption that the laundering process would have removed all seminal fluid and spermatozoa. The aim of this study was to examine the persistence of seminal fluid and spermatozoa on a range of fabric types including cotton, nylon, terry towel (100% cotton), polyester fleece, satin and lace which were laundered up to six times. Three techniques were used for the detection of seminal fluid and spermatozoa: an alternative light source, acid phosphatase test and microscopy. The study demonstrated that spermatozoa persisted on cotton and terry towel following six wash cycles. This data emphasises the need to recover and examine items of clothing and bedding of victims for semen, even if the item has been washed multiple times. Copyright © 2018 Elsevier B.V. All rights reserved.

Biosensor technology for the detection of illegal drugs II: antibody development and detection techniques

NASA Astrophysics Data System (ADS)

Hilpert, Reinhold; Bauer, Christian; Binder, Florian; Grol, Michael; Hallermayer, Klaus; Josel, Hans-Peter; Klein, Christian; Maier, Josef; Makower, Alexander; Oberpriller, Helmut; Ritter, Josef

1994-10-01

In a joint project of Deutsche Aerospace, Boehringer Mannheim and the University of Potsdam portable devices for the detection of illegal drugs, based on biosensor technology, are being developed. The concept enrichment of the drug from the gas phase and detection by immunological means. This publication covers the development of specific antibodies and various detection procedures. Antibodies with a high affinity for cocaine have been developed with the aid of specially synthesized immunogens. A competitive detection procedure with biosensors based on optical grating couplers and applying particulate labels has been established, showing a lower detection limit of 10-10 mol/l for cocaine. Additionally, a combination of a displacement-immunoreactor and an enzymatically amplified electrode was investigated, which at present still suffers from insufficient sensitivity of the immunoreactor. An alternative, fleece-matrix based test procedure, where enrichment and detection steps are integrated in a single unit, is promising in terms of simplicity and sensitivity. A simple swab-test for the detection of cocaine at surfaces has been developed, which has a lower detection limit of about 10 ng and which can be performed within one minute.

Identification and disruption of bacteria associated with sheep scab mites-novel means of control?

PubMed

Hall, S A; Mack, K; Blackwell, A; Evans, K A

2015-10-01

Psoroptes ovis mites, which cause psoroptic mange (sheep scab), were investigated to identify potential bacterial targets for endosymbiont control of sheep scab. In addition, transmission of bacteria to the sheep skin was investigated through the characterisation of bacteria present in P. ovis faecal trails and on the fleece environment by internal transcribed spacer (ITS) sequencing. A diverse range of bacteria was identified in addition to a potential endosymbiont candidate, Comamonas sp, which was detected in P. ovis by both ITS PCR and endosymbiont-specific PCR. Disruption of these bacteria within P. ovis, through the use of antibiotics, was explored; with significant reduction in mean mite survival when administered antibiotic diets compared with controls (LR4 = 23.12, P < 0.001). The antibiotic treatments also significantly affected the bacterial density (CFU/mite) within P. ovis, indicating that mite survival may be linked to the bacterial communities that they harbour. Although antibiotics are not suitable for practical application, these results suggest disrupting bacteria associated with P. ovis should be further investigated for novel control. Copyright © 2015 Elsevier Inc. All rights reserved.

Genetic parameters for carcass and meat quality traits and their relationships to liveweight and wool production in hogget Merino rams.

PubMed

Greeff, J C; Safari, E; Fogarty, N M; Hopkins, D L; Brien, F D; Atkins, K D; Mortimer, S I; van der Werf, J H J

2008-06-01

Genetic parameters for carcass and meat quality traits of about 18-month-old Merino rams (n = 5870), the progeny of 543 sires from three research resource flocks, were estimated. The estimates of heritability for hot carcass weight (HCW) and the various fat and muscle dimension measurements were moderate and ranged from 0.20 to 0.37. The brightness of meat (colour L*, 0.18 +/- 0.03 standard error) and meat pH (0.22 +/- 0.03) also had moderate estimates of heritability, although meat relative redness (colour a*, 0.10 +/- 0.03) and relative yellowness (colour b*, 0.10 +/- 0.03) were lower. Heritability estimates for live weights were moderate and ranged from 0.29 to 0.41 with significant permanent maternal environmental effects (0.13 to 0.10). The heritability estimates for the hogget wool traits were moderate to high and ranged from 0.27 to 0.60. The ultrasound measurements of fat depth (FATUS) and eye muscle depth (EMDUS) on live animals were highly genetically correlated with the corresponding carcass measurements (0.69 +/- 0.09 FATC and 0.77 +/- 0.07 EMD). Carcass tissue depth (FATGR) had moderate to low genetic correlations with carcass muscle measurements [0.18 +/- 0.10 EMD and 0.05 +/- 0.10 eye muscle area (EMA)], while those with FATC were negative. The genetic correlation between EMD and eye muscle width (EMW) was 0.41 +/- 0.08, while EMA was highly correlated with EMD (0.89 +/- 0.0) and EMW (0.78 +/- 0.04). The genetic correlations for muscle colour with muscle measurements were moderately negative, while those with fat measurements were close to zero. Meat pH was positively correlated with muscle measurements (0.14 to 0.17) and negatively correlated with fat measurements (-0.06 to -0.18). EMDUS also showed a similar pattern of correlations to EMD with meat quality indicator traits, although FATUS had positive correlations with these traits which were generally smaller than their standard error. The genetic correlations among the meat colour traits were high and positive while those with meat pH were high and negative, which were all in the favourable direction. Generally, phenotypic correlations were similar or slightly lower than the corresponding genetic correlations. There were generally small to moderate negative genetic correlations between clean fleece weight (CFW) and carcass fat traits while those with muscle traits were close to zero. As the Merino is already a relatively lean breed, this implies that particular attention should be given to this relationship in Merino breeding programmes to prevent the reduction of fat reserves as a correlated response to selection for increased fleece weight. The ultrasound scan traits generally showed a similar pattern to the corresponding carcass fat and muscle traits. There was a small unfavourable genetic correlation between CFW and meat pH (0.19 +/- 0.07).

A comparison between Poisson and zero-inflated Poisson regression models with an application to number of black spots in Corriedale sheep

PubMed Central

Naya, Hugo; Urioste, Jorge I; Chang, Yu-Mei; Rodrigues-Motta, Mariana; Kremer, Roberto; Gianola, Daniel

2008-01-01

Dark spots in the fleece area are often associated with dark fibres in wool, which limits its competitiveness with other textile fibres. Field data from a sheep experiment in Uruguay revealed an excess number of zeros for dark spots. We compared the performance of four Poisson and zero-inflated Poisson (ZIP) models under four simulation scenarios. All models performed reasonably well under the same scenario for which the data were simulated. The deviance information criterion favoured a Poisson model with residual, while the ZIP model with a residual gave estimates closer to their true values under all simulation scenarios. Both Poisson and ZIP models with an error term at the regression level performed better than their counterparts without such an error. Field data from Corriedale sheep were analysed with Poisson and ZIP models with residuals. Parameter estimates were similar for both models. Although the posterior distribution of the sire variance was skewed due to a small number of rams in the dataset, the median of this variance suggested a scope for genetic selection. The main environmental factor was the age of the sheep at shearing. In summary, age related processes seem to drive the number of dark spots in this breed of sheep. PMID:18558072

Investigation of genetic divergence and polymorphism of nuclear DNA in species and populations of domestic and wild sheep

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mel`nikova, M.N.; Grechko, V.V.; Mednikov, B.M.

1995-08-01

Genetic divergence in repetitive sequences of nuclear DNA of wild and domestic sheep was studied by general restriction endonuclease mapping (i.e., the taxonoprint method). The PCR RAPD method with one and two arbitrary primers was also used to analyze the nuclear DNA polymorphism in some other regions. The taxonoprint method, performed using six endonucleases, showed specificity and virtually complete similarity in the patterns of repetitive DNA sequences of two wild forms, argali and moufflon, and five domestic sheep breeds. Central Asian breeds, Kazakh fine-fleeced, karakuk, ghissar, and eadeelbay, and an English breed, Lincoln, were examined. The results confirm the opinionmore » that wild and domestic sheep may be considered one polytypic species. The PCR-RAPD method, both with one and two arbitrary primers, revealed a closer similarity of all the sheep breeds examined when aragali, rather than with moufflon, was used. These results indicate that the domestication area of sheep was much more broader than was earlier presumed. Otherwise, hybridizations of domestic and wild forms could occasionally occur in the area of their coexistence. The amplification patterns of PCR-RAPD products are the most promising population genetic markers. 27 refs., 4 figs., 7 tabs.« less

Bacterial nanocellulose stimulates mesenchymal stem cell expansion and formation of stable collagen-I networks as a novel biomaterial in tissue engineering.

PubMed

Vielreicher, Martin; Kralisch, Dana; Völkl, Simon; Sternal, Fabian; Arkudas, Andreas; Friedrich, Oliver

2018-06-20

Biomimetic scaffolds are of great interest to tissue engineering (TE) and tissue repair as they support important cell functions. Scaffold coating with soluble collagen-I has been used to achieve better tissue integration in orthopaedy, however, as collagen persistence was only temporary such efforts were limited. Adequate coverage with cell-derived ECM collagen-I would promise great success, in particular for TE of mechanically challenged tissues. Here, we have used label-free, non-invasive multiphoton microscopy (MPM) to characterise bacterial nanocellulose (BNC) - a promising biomaterial for bone TE - and their potency to stimulate collagen-I formation by mesenchymal stem cells (MSCs). BNC fleeces were investigated by Second Harmonic Generation (SHG) imaging and by their characteristic autofluorescence (AF) pattern, here described for the first time. Seeded MSCs adhered fast, tight and very stable, grew to multilayers and formed characteristic, wide-spread and long-lasting collagen-I. MSCs used micron-sized lacunae and cracks on the BNC surface as cell niches. Detailed analysis using a collagen-I specific binding protein revealed a highly ordered collagen network structure at the cell-material interface. In addition, we have evidence that BNC is able to stimulate MSCs towards osteogenic differentiation. These findings offer new options for the development of engineered tissue constructs based on BNC.

Human fetal bone cells in delivery systems for bone engineering.

PubMed

Tenorio, Diene M H; Scaletta, Corinne; Jaccoud, Sandra; Hirt-Burri, Nathalie; Pioletti, Dominique P; Jaques, Bertrand; Applegate, Lee Ann

2011-11-01

The aim of this study was to culture human fetal bone cells (dedicated cell banks of fetal bone derived from 14 week gestation femurs) within both hyaluronic acid gel and collagen foam, to compare the biocompatibility of both matrices as potential delivery systems for bone engineering and particularly for oral application. Fetal bone cell banks were prepared from one organ donation and cells were cultured for up to 4 weeks within hyaluronic acid (Mesolis®) and collagen foams (TissueFleece®). Cell survival and differentiation were assessed by cell proliferation assays and histology of frozen sections stained with Giemsa, von Kossa and ALP at 1, 2 and 4 weeks of culture. Within both materials, fetal bone cells could proliferate in three-dimensional structure at ∼70% capacity compared to monolayer culture. In addition, these cells were positive for ALP and von Kossa staining, indicating cellular differentiation and matrix production. Collagen foam provides a better structure for fetal bone cell delivery if cavity filling is necessary and hydrogels would permit an injectable technique for difficult to treat areas. In all, there was high biocompatibility, cellular differentiation and matrix deposition seen in both matrices by fetal bone cells, allowing for easy cell delivery for bone stimulation in vivo. Copyright © 2011 John Wiley & Sons, Ltd.

Accumulation of Zn, Cd, Cu, and Pb in Chinese cabbage as influenced by climatic conditions under protected cultivation.

PubMed

Moreno, Diego A; Víllora, Gemma; Hernández, Joaquín; Castilla, Nicolás; Romero, Luis

2002-03-27

Accumulation of heavy metals from agricultural soils contaminated by low levels heavy metals has important implications in the understanding of heavy metal contamination in the food chain. Through field experiments (1994-1996), the influence of thermal regime under different treatments on the accumulation of zinc, cadmium, copper, and lead in Chinese cabbage [Brassica pekinensis (Lour) Rupr. cv. Nagaoka 50] grown in a Calcareous Fluvisol (Xerofluvent) in Granada (southern Spain) was examined. Two floating row covers were used: T(1) (perforated polyethylene, 50 microm thick) and T(2) (17 g m(-2) polypropylene nonwoven fleece). An uncovered cultivation (T(0)) served as control. Zn, Cd, Cu, and Pb levels in the whole tops of experimental plants were analyzed. Treatments T(1) and T(2) gave rise to differences in environmental conditions with respect to T(0). The influence of environmental factors manipulated by floating row covers (particularly under T(1)) increased total heavy metal accumulation in the above ground plant biomass with respect to the open-air crop. The total contents of Zn, Cd, Cu, and Pb were 30, 50, 90, and 40% higher in T(1), respectively, than in T(0). This technique could be used in contaminated zones for different plant species because the thermal effect favors the process of phytoextraction and thus reduces the contamination.

Durable Suit Bladder with Improved Water Permeability for Pressure and Environment Suits

NASA Technical Reports Server (NTRS)

Bue, Grant C.; Kuznetz, Larry; Orndoff, Evelyne; Tang, Henry; Aitchison, Lindsay; Ross, Amy

2009-01-01

Water vapor permeability is shown to be useful in rejecting heat and managing moisture accumulation in launch-and-entry pressure suits. Currently this is accomplished through a porous Gortex layer in the Advanced Crew and Escape Suit (ACES) and in the baseline design of the Constellation Suit System Element (CSSE) Suit 1. Non-porous dense monolithic membranes (DMM) that are available offer potential improvements for water vapor permeability with reduced gas leak. Accordingly, three different pressure bladder materials were investigated for water vapor permeability and oxygen leak: ElasthaneTM 80A (thermoplastic polyether urethane) provided from stock polymer material and two custom thermoplastic polyether urethanes. Water vapor, carbon dioxide and oxygen permeability of the DMM's was measured in a 0.13 mm thick stand-alone layer, a 0.08 mm and 0.05 mm thick layer each bonded to two different nylon and polyester woven reinforcing materials. Additional water vapor permeability and mechanical compression measurements were made with the reinforced 0.05 mm thick layers, further bonded with a polyester wicking and overlaid with moistened polyester fleece thermal underwear .This simulated the pressure from a supine crew person. The 0.05 mm thick nylon reinforced sample with polyester wicking layer was further mechanically tested for wear and abrasion. Concepts for incorporating these materials in launch/entry and Extravehicular Activity pressure suits are presented.

Effects of sarcoptic mange and its control with oil of Cedrus deodara, Pongamia glabra, Jatropha curcas and benzyl benzoate, both with and without ascorbic acid on growing sheep: assessment of weight gain, liver function, nutrient digestibility, wool production and meat quality.

PubMed

Dimri, U; Sharma, M C

2004-03-01

The aim of this study was to evaluate the therapeutic efficacy of commonly used acaricidal drugs in India and also to assess the effect of ascorbic acid as adjunct therapy in 72 growing sheep with sarcoptic mange, aged 5-6 months and weighing 20.4-31.7 kg. Eight replicates of nine animals were formed based on sex, and day 0 body weight. Drugs were applied locally on the affected parts daily and recovery changes in skin lesions were observed at the time of every application. L-ascorbic acid was administered intramuscularly. Skin scrapings were collected daily from each group and examined for the presence of mites. Body weights were measured every 10th day from day 0 to 60. Nutrient digestiblity was evaluated by studying digestibility coefficients for dry matter, crude protein, ether extract, crude fibre, nitrogen free extract, total carbohydrates and nutrient balance (nitrogen, calcium and phosphorus) for a 30-day period. The liver function was evaluated by bromosulphophthalein (BSP) dye retention time. The animals were shorn on day 60 post-treatment (PT). Meat quality assesment was carried out by killing sheep at 60 days PT and estimating pH, water-holding capacity (WHC), tenderness, muscle colour, rib eye area and fat thickness. The lambs treated with oil of Jatropha curcas ascorbic acid had significantly (P < 0.05) greater mean daily body weight gains (63.29 g) than the infected untreated control (41.10 g). This was also higher than the mean daily weight gain in other treated groups. Infected untreated sheep showed significantly (P < 0.01) reduced digestibility coefficients for dry matter, crude protein, crude fibre, ether extract and total carbohydrate, but no significant differences for nitrogen-free extract. Treated sheep had significantly higher positive nitrogen, calcium and phosphorus balances compared with infested untreated sheep. Oil of J. curcas plus ascorbic acid (OJC-AA) treated group was better over all other treated groups with respect to nutrient digestibility. The BSP test revealed significant (P < 0.05) increase in BSP retention time in sheep with sarcoptic mange. Post -treatment, the BSP retention time decreased in all treated groups and the decrease was maximum in OJC-AA treated group. The carcasses of sheep treated with OJC-AA had significantly (P < 0.01) higher water holding capacity, rib eye area and back fat thickness than the untreated infected control group. The muscle pH and tenderness values were significantly lower in OJC-AA treated group post-slaughter than infested untreated control group. Muscle colour of OJC-AA treated group was maximum bright red. The lambs treated with OJC-AA had significantly (P < 0.05) greater clean fleece weight and fleece yield than the untreated infected group. It is concluded that OJC was the better therapy for sarcoptic mange of sheep and ascorbic acid as adjunct therapy is advisable. OJC-AA therapy may be better from the point of view of improving two most important production parameters in sheep, that is, wool yield and meat production.

Parahippocampal cortex is involved in material processing via echoes in blind echolocation experts.

PubMed

Milne, Jennifer L; Arnott, Stephen R; Kish, Daniel; Goodale, Melvyn A; Thaler, Lore

2015-04-01

Some blind humans use sound to navigate by emitting mouth-clicks and listening to the echoes that reflect from silent objects and surfaces in their surroundings. These echoes contain information about the size, shape, location, and material properties of objects. Here we present results from an fMRI experiment that investigated the neural activity underlying the processing of materials through echolocation. Three blind echolocation experts (as well as three blind and three sighted non-echolocating control participants) took part in the experiment. First, we made binaural sound recordings in the ears of each echolocator while he produced clicks in the presence of one of three different materials (fleece, synthetic foliage, or whiteboard), or while he made clicks in an empty room. During fMRI scanning these recordings were played back to participants. Remarkably, all participants were able to identify each of the three materials reliably, as well as the empty room. Furthermore, a whole brain analysis, in which we isolated the processing of just the reflected echoes, revealed a material-related increase in BOLD activation in a region of left parahippocampal cortex in the echolocating participants, but not in the blind or sighted control participants. Our results, in combination with previous findings about brain areas involved in material processing, are consistent with the idea that material processing by means of echolocation relies on a multi-modal material processing area in parahippocampal cortex. Copyright © 2014 Elsevier Ltd. All rights reserved.

Local antimicrobial administration for prophylaxis of surgical site infections.

PubMed

Huiras, Paul; Logan, Jill K; Papadopoulos, Stella; Whitney, Dana

2012-11-01

Despite a lack of consensus guidelines, local antibiotic administration for prophylaxis of surgical site infections is used during many surgical procedures. The rationale behind this practice is to provide high antibiotic concentrations at the site of surgery while minimizing systemic exposure and adverse effects. Local antibiotic administration for surgical site prophylaxis has inherent limitations in that antibiotics are applied after the incision is made, rather than the current standard for surgical site prophylaxis that recommends providing adequate antibiotic concentrations at the site before the incision. The efficacy and safety of local application of antibiotics for surgical site prophylaxis have been assessed in different types of surgery with a variety of antibiotic agents and methods of application. We identified 22 prospective, randomized, controlled trials that evaluated local application of antibiotics for surgical site prophylaxis. These trials were subsequently divided and analyzed based on the type of surgical procedure: dermatologic, orthopedic, abdominal, colorectal, and cardiothoracic. Methods of local application analyzed included irrigations, powders, ointments, pastes, beads, sponges, and fleeces. Overall, there is a significant lack of level I evidence supporting this practice for any of the surgical genres evaluated. In addition, the literature spans several decades, and changes in surgical procedures, systemic antibiotic prophylaxis, and microbial flora make conclusions difficult to determine. Based on available data, the efficacy of local antibiotic administration for the prophylaxis of surgical site infections remains uncertain, and recommendations supporting this practice for surgical site prophylaxis cannot be made. © 2012 Pharmacotherapy Publications, Inc.

The calculation from weather records of the requirement for clothing insulation

NASA Astrophysics Data System (ADS)

Mount, L. E.; Brown, D.

1985-12-01

Standard meteorological measurements of dry bulb temperature, wind speed, sunshine, cloud cover and rainfall are used to calculate the clothing insulation required by man for thermal comfort under given weather conditions. The calculation is based on earlier work on the effect of weather on sensible (non-evaporative) heat loss from sheep, which used the relation between heat flow, thermal insulation and the difference between body and environmental temperatures. Clothing insulation for man is estimated in two ways: as clothing (Ic) that is impervious to the effects of wind and rain; and as the equivalent depth of sheep fleece (fm), which is not impervious. This allows the assessment of wind chill for a range of clothing of varied penetration by wind instead of for only one type of garment. Results are given as daily means calculated from hourly measurements throughout 1973 for Plymouth (on the south coast of Britain) and Aberdeen (on the far northeast coast of Britain). Wind chill is estimated both by its effect on fm requirement and by the fall in air temperature that would be needed to produce under still-air conditions the same demand for fm that occurs in the actual environment. The monthly mean fm requirement is reduced by about 40% when the effect of wind is removed. When wind chill is estimated as an equivalent fall in air temperature it approximates to 1 K per knot wind speed measured at the standard meteorological height of 10 m.

QTL and association analysis for skin and fibre pigmentation in sheep provides evidence of a major causative mutation and epistatic effects.

PubMed

Raadsma, H W; Jonas, E; Fleet, M R; Fullard, K; Gongora, J; Cavanagh, C R; Tammen, I; Thomson, P C

2013-08-01

The pursuits of white features and white fleeces free of pigmented fibre have been important selection objectives for many sheep breeds. The cause and inheritance of non-white colour patterns in sheep has been studied since the early 19th century. Discovery of genetic causes, especially those which predispose pigmentation in white sheep, may lead to more accurate selection tools for improved apparel wool. This article describes an extended QTL study for 13 skin and fibre pigmentation traits in sheep. A total of 19 highly significant, 10 significant and seven suggestive QTL were identified in a QTL mapping experiment using an Awassi × Merino × Merino backcross sheep population. All QTL on chromosome 2 exceeded a LOD score of greater than 4 (range 4.4-30.1), giving very strong support for a major gene for pigmentation on this chromosome. Evidence of epistatic interactions was found for QTL for four traits on chromosomes 2 and 19. The ovine TYRP1 gene on OAR 2 was sequenced as a strong positional candidate gene. A highly significant association (P < 0.01) of grandparental haplotypes across nine segregating SNP/microsatellite markers including one non-synonymous SNP with pigmentation traits could be shown. Up to 47% of the observed variation in pigmentation was accounted for by models using TYRP1 haplotypes and 83% for models with interactions between two QTL probabilities, offering scope for marker-assisted selection for these traits. © 2013 The Authors, Animal Genetics © 2013 Stichting International Foundation for Animal Genetics.

Compression-induced structural and mechanical changes of fibrin-collagen composites.

PubMed

Kim, O V; Litvinov, R I; Chen, J; Chen, D Z; Weisel, J W; Alber, M S

2017-07-01

Fibrin and collagen as well as their combinations play an important biological role in tissue regeneration and are widely employed in surgery as fleeces or sealants and in bioengineering as tissue scaffolds. Earlier studies demonstrated that fibrin-collagen composite networks displayed improved tensile mechanical properties compared to the isolated protein matrices. Unlike previous studies, here unconfined compression was applied to a fibrin-collagen filamentous polymer composite matrix to study its structural and mechanical responses to compressive deformation. Combining collagen with fibrin resulted in formation of a composite hydrogel exhibiting synergistic mechanical properties compared to the isolated fibrin and collagen matrices. Specifically, the composite matrix revealed a one order of magnitude increase in the shear storage modulus at compressive strains>0.8 in response to compression compared to the mechanical features of individual components. These material enhancements were attributed to the observed structural alterations, such as network density changes, an increase in connectivity along with criss-crossing, and bundling of fibers. In addition, the compressed composite collagen/fibrin networks revealed a non-linear transformation of their viscoelastic properties with softening and stiffening regimes. These transitions were shown to depend on protein concentrations. Namely, a decrease in protein content drastically affected the mechanical response of the networks to compression by shifting the onset of stiffening to higher degrees of compression. Since both natural and artificially composed extracellular matrices experience compression in various (patho)physiological conditions, our results provide new insights into the structural biomechanics of the polymeric composite matrix that can help to create fibrin-collagen sealants, sponges, and tissue scaffolds with tunable and predictable mechanical properties. Copyright © 2016 Elsevier B.V. All rights reserved.

Sheep laterality.

PubMed

Anderson, Dean M; Murray, Leigh W

2013-01-01

Turning preferences among 309 white-faced ewes were individually evaluated in an enclosed, artificially lit T-maze, followed by each ewe choosing either a right or left return alley to return to peers. Data recorded included time in the start box, time in the T-maze, exit arm chosen to leave the T-maze, and return alley. Right and left arms of the T-maze were chosen 65.7% and 34.3% of the time, respectively, while right and left return alleys were chosen 32.4% and 67.6%, respectively. Exit arm and return alley were not independently chosen (p <.0001), with observed counts being higher than expected under independence when ewes made the same choice for exit and alley (RR or LL turn patterns) and being lower than expected for alternating choices (RL or LR). Out of the 309 ewes, 28.2% and 30.1% chose RR and LL turn patterns, respectively, while 37.5% chose the RL turn pattern, but only 13 (4.2%) chose the LR turning pattern. Overall, ewes that initially turned right when presented a second turning opportunity had a slight preference to alternate their turning direction, while ewes that initially turned left tended to continue turning left when given another chance to turn. Exit arm and return alley laterality was not related (α =.05) to time of day the test was administered, ewe's age or genetics, most recent liveweight, or most recent shorn fleece weight. The mean time spent in the start box (21 s) was not related to exit arm (p =.947) or return alley (p =.779). Mean time (15 s) spent in the T-maze was not related to exit arm (p =.086) or return alley (p =.952). More research will be required to understand sheep turning laterality and how it can impact working facilities and research equipment.

The detection of capsaicin and dihydrocapsaicin in horse serum following long-term local administration.

PubMed

Zak, A; Siwinska, N; Slowikowska, M; Borowicz, H; Szpot, P; Zawadzki, M; Niedzwiedz, A

2018-06-19

Capsaicin and dihydrocapsaicin are alkaloids with analgesic effects in humans and animals. When used locally, both of them minimalise pain sensation by defunctionalising nerve endings. According to the Federation Equestrian International Prohibited Substances List, these are substance banned in horse competitions. The aim of the study was to determine the detection time of capsaicin in both plasma and serum after long-term use of a gel recommended for commercial use and applied as intended. The objective of the study was to select the best material for the detection of capsaicin as a doping substance in horses. Nine healthy mature horses were administered 0.1% capsaicin topically in the form of a commercial analgesic gel (15 g of the gel per limb) to the front limbs every 24 hours for five days with a polar fleece bandage. Blood serum and plasma were collected prior to gel application and in the 12th, 18th, 24th, 36th, 42nd, 48th, 60th, 84th, 108th, 132nd, 156th hour after the gel application. Qualitative and quantitative analysis was performed using ultra-high performance liquid chromatography coupled with a triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS). The concentration of capsaicin in the serum samples did not exceed the lower limit of quantification. Capsaicin was not detected in the plasma samples during the entire study period. Dihydrocapsaicin was not detected in blood serum or plasma. The presented results suggest that capsaicin is not detected in horse serum in the 24-hour-periodfollowing its last application according to the dosage regimen used by owners and veterinarians for therapy rather than doping, based on a five day gel application and a polar bandage.

Microbiological efficacy of superheated steam. I. Communication: results with spores of Bacillus subtilis and Bacillus stearothermophilus and with spore earth.

PubMed

Spicher, G; Peters, J; Borchers, U

1999-02-01

For the spores of Bacillus subtilis and Bacillus stearothermophilus as well as for spore earth (acc. DIN 58,946 Part 4 of August 1982), the dependence of resistance on the superheating of the steam used to kill germs was determined. A material (glass fibre fleece) was used as the germ carrier which does not superheat on contact with steam. The temperature of the saturated steam was 100 degrees C (B. subtilis) and 120 degrees C (B. stearothermophilus and spore earth). The yardstick for the resistance of the spores or bioindicators was the exposure period of the saturated or superheated steam at which 50% of the treated test objects no longer showed any viable test germs. The spores of Bacillus subtilis were far more sensitive to superheating of steam and reacted far more than the spores of Bacillus stearothermophilus and the germs in the spore earth. When superheating by 4 Kelvin the spores of Bacillus subtilis were approximately 2.5 times more resistant than they were to saturated steam. The resistance of Bacillus stearothermophilus and spore earth was only slightly higher up to superheating by 10 Kelvin. The spores of Bacillus subtilis had the highest resistance during superheating by 29 Kelvin; they were 119 times more resistant than they were to saturated steam. The resistance maximum of the spores of Bacillus stearothermophilus was at an superheating by around 22 Kelvin. However, the spores were only 4.1 times more resistant than they were to saturated steam. When using steam to kill germs, we must expect superheated steam. This raises the question whether the spores of Bacillus stearothermophilus, with their weaker reaction to the superheating of steam, are suitable as test germs for sterilisation with steam in all cases.

Three-dimensional kinematics of the equine metacarpophalangeal joint using x-ray reconstruction of moving morphology - a pilot study.

PubMed

Childs, Bronwen A; Pugliese, Brenna R; Carballo, Cristina T; Miranda, Daniel L; Brainerd, Elizabeth L; Kirker-Head, Carl A

2017-07-20

X-ray reconstruction of moving morphology (XROMM) uses biplanar videoradiography and computed tomography (CT) scanning to capture three-dimensional (3D) bone motion. In XROMM, morphologically accurate 3D bone models derived from CT are animated with motion from videoradiography, yielding a highly accurate and precise reconstruction of skeletal kinematics. We employ this motion analysis technique to characterize metacarpophalangeal joint (MCPJ) motion in the absence and presence of protective legwear in a healthy pony. Our in vivo marker tracking precision was 0.09 mm for walk and trot, and 0.10 mm during jump down exercises. We report MCPJ maximum extension (walk: -27.70 ± 2.78° [standard deviation]; trot: -33.84 ± 4.94°), abduction/adduction (walk: 0.04 ± 0.24°; trot: -0.23 ± 0.35°) and external/internal rotations (walk: 0.30 ± 0.32°; trot: -0.49 ± 1.05°) indicating that the MCPJ in this pony is a stable hinge joint with negligible extra-sagittal rotations. No substantial change in MCPJ maximum extension angles or vertical ground reaction forces (GRFv) were observed upon application of legwear during jump down exercise. Neoprene boot application yielded -65.20 ± 2.06° extension (GRFv = 11.97 ± 0.67 N/kg) and fleece polo wrap application yielded -64.23 ± 1.68° extension (GRFv = 11.36 ± 1.66 N/kg), when compared to naked control (-66.11 ± 0.96°; GRFv = 12.02 ± 0.53 N/kg). Collectively, this proof of concept study illustrates the benefits and practical limitations of using XROMM to document equine MCPJ kinematics in the presence and absence of legwear.

Screening study of four environmentally relevant microplastic pollutants: Uptake and effects on Daphnia magna and Artemia franciscana.

PubMed

Kokalj, Anita Jemec; Kunej, Urban; Skalar, Tina

2018-06-08

This study investigated four different environmentally relevant microplastic (MP) pollutants which were derived from two facial cleansers, a plastic bag and polyethylene textile fleece. The mean size range of the particles (according to number distribution) was 20-250 μm when measured as a powder and 0.02-200 μm in suspension. In all MP exposures, plastic particles were found inside the guts of D. magna and A. franciscana, but only in the case of daphnids a clear exponential correlation between MP uptake in the gut and the size of the MP was identified. Exposure tests in which the majority of the MP particles were below 100 μm in size also had higher numbers of daphnids displaying evidence of MP ingestion. As the average MP particle size increased, the percentage of daphnids which had MP in their gut decreased. Using a number distribution value to measure particle size when in a suspension is more experimentally relevant as it provides a more realistic particle size than when samples are measured as a powder. Generally, artemias had fewer MP particles in the gut, than the daphnids, which could be explained by their different food size preferences. No acute effects on D. magna were found, but the growth of A. franciscana was affected. We conclude that zooplankton crustacean can ingest various MPs but none of the exposures tested were highly acutely hazardous to the test species. In addition, no delayed lethal effects in a 24 h post-exposure period were found. Copyright © 2018 Elsevier Ltd. All rights reserved.

Catalytic combustion of volatile organic compounds.

PubMed

Everaert, K; Baeyens, J

2004-06-18

Despite the success of adsorption and thermal incineration of (C)VOC emissions, there is still a need for research on techniques which are both economically more favorable and actually destroy the pollutants rather than merely remove them for recycling elsewhere in the biosphere. The catalytic destruction of (C)VOC to CO2, H2O and HCl/Cl2 appears very promising in this context and is the subject of the present paper. The experiments mainly investigate the catalytic combustion of eight target compounds, all of which are commonly encountered in (C)VOC emissions and/or act as precursors for the formation of PCDD/F. Available literature on the different catalysts active in the oxidation of (C)VOC is reviewed and the transition metal oxide complex V2O5-WO3/TiO2 appears most suitable for the current application. Different reactor geometries (e.g. fixed pellet beds, honeycombs, etc.) are also described. In this research a novel catalyst type is introduced, consisting of a V2O5-WO3/TiO2 coated metal fiber fleece. The conversion of (C)VOC by thermo-catalytic reactions is governed by both reaction kinetics and reaction equilibrium. Full conversion of all investigated VOC to CO2, Cl2, HCl and H2O is thermodynamically feasible within the range of experimental conditions used in this work (260-340 degrees C, feed concentrations 30-60 ppm). A first-order rate equation is proposed for the (C)VOC oxidation reactions. The apparent rate constant is a combination of reaction kinetics and mass transfer effects. The oxidation efficiencies were measured with various (C)VOC in the temperature range of 260-340 degrees C. Literature data for oxidation reactions in fixed beds and honeycomb reactors are included in the assessment. Mass transfer resistances are calculated and are generally negligible for fleece reactors and fixed pellet beds, but can be of importance for honeycomb monoliths. The experimental investigations demonstrate: (i) that the conversion of the hydrocarbons is independent of the oxygen concentration, corresponding to a zero-order dependency of the reaction rate; (ii) that the conversion of the hydrocarbons is a first-order reaction in the (C)VOC; (iii) that the oxidation of the (C)VOC proceeds to a higher extent with increasing temperature, with multiple chlorine substitution enhancing the reactivity; (iv) that the reaction rate constant follows an Arrhenius dependency. The reaction rate constant kr (s(-1)) and the activation energy E (kJ/mol) are determined from the experimental results. The activation energy is related to the characteristics of the (C)VOC under scrutiny and correlated in terms of the molecular weight. The kr-values are system-dependent and hence limited in design application to the specific VOC-catalyst combination being studied. To achieve system-independency, kr-values are transformed into an alternative kinetic constant K (m3/(m2u)) expressed per unit of catalyst surface and thus independent of the amount of catalyst present in the reactor. Largely different experimental data can be fitted in terms of this approach. Results are thereafter used to define the Arrhenius pre-exponential factor A*, itself expressed in terms of the activation entropy. Destruction efficiencies for any given reactor set-up can be predicted from E- and A*-correlations. The excellent comparison of predicted and measured destruction efficiencies for a group of chlorinated aromatics stresses the validity of the design approach. Since laboratory-scale experiments using PCDD/F are impossible, pilot and full-scale tests of PCDD/F oxidation undertaken in Flemish MSWIs and obtained from literature are reported. From the data it is clear that: (i) destruction efficiencies are normally excellent; (ii) the efficiencies increase with increasing operating temperature; (iii) the higher degree of chlorination does not markedly affect the destruction efficiency. Finally, all experimental findings are used in design recommendations for the catalytic oxidation of (C)VOC and PCDD/F. Predicted values of the a)VOC and PCDD/F. Predicted values of the acceptable space velocity correspond with the cited industrial values, thus stressing the validity of the design strategy and equations developed in the present paper.

Genetic trend for growth and wool performance in a closed flock of Bharat Merino sheep at sub temperate region of Kodai hills, Tamil Nadu.

PubMed

Mallick, P K; Thirumaran, S M K; Pourouchottamane, R; Rajapandi, S; Venkataramanan, R; Nagarajan, G; Murali, G; Rajendiran, A S

2016-03-01

The study was conducted at Southern Regional Research Center, ICAR-Central Sheep and Wool Research Institute (CSWRI), Mannavanur, Kodaikanal, Tamil Nadu to estimate genetic trends for birth weight (BWT), weaning weight (3WT), 6 months weight (6WT), and greasy fleece weight (GFY) in a Bharat Merino (BM) flock, where selection was practiced for 6WT and GFY. The data for this study represents a total of 1652 BM lambs; progeny of 144 sires spread over 15 years starting from 2000 to 2014, obtained from the BM flock of ICAR-SRRC (CSWRI), Mannavanur, Kodaikanal, Tamil Nadu, India. The genetic trends were calculated by regression of average predicted breeding values using software WOMBAT for the traits BWT, 3WT, 6WT and GFY versus the animal's birth year. The least square means were 3.28±0.02 kg, 19.08±0.23 kg, 25.00±0.35 kg and 2.13±0.07 kg for BWT, 3WT, 6WT and GFY, respectively. Genetic trends were positive and highly significant (p<0.01) for BWT, while the values for 3WT, 6WT and GFY though positive, were not significant. The estimates of genetic trends in BWT, 3WT, 6WT and GFY were 5 g, 0.8 g, 7 g and 0.3 g/year gain and the fit of the regression shows 55%, 22%, 42% and 12% coefficient of determination with the regressed value, respectively. In this study, estimated mean predicted breeding value (kg) in BWT and 3WT, 6WT and GFY were 0.067, 0.008, 0.036 and -0.003, respectively. Estimates of genetic trends indicated that there was a positive genetic improvement in all studied traits and selection would be effective for the improvement of body weight traits and GFY of BM sheep.

Good results in postoperative and hematogenous deep infections of 89 stable total hip and knee replacements with retention of prosthesis and local antibiotics.

PubMed

Geurts, Jan A P; Janssen, Daniël M C; Kessels, Alfons G H; Walenkamp, Geert H I M

2013-12-01

Deep postoperative and hematogenous prosthesis infections may be treated with retention of the prosthesis, if the prosthesis is stable. How long the infection may be present to preclude a good result is unclear. We retrospectively studied 89 deep-infected stable prostheses from 69 total hip replacements and 20 total knee replacements. There were 83 early or delayed postoperative infections and 6 hematogenous. In the postoperative infections, treatment had started 12 days to 2 years after implantation. In the hematogenous infections, symptoms had been present for 6 to 9 days. The patients had been treated with debridement, prosthesis retention, systemic antibiotics, and local antibiotics: gentamicin-PMMA beads or gentamicin collagen fleeces. The minimum follow-up time was 1.5 years. We investigated how the result of the treatment had been influenced by the length of the period the infection was present, and by other variables such as host characteristics, infection stage, and type of bacteria. In postoperative infections, the risk of failure increased with a longer postoperative interval: from 0.2 (95% CI: 0.1-0.3) if the treatment had started ≥ 4 weeks postoperatively to 0.5 (CI: 0.2-0.8) if it had started at ≥ 8 weeks. The relative risk for success was 0.6 (CI: 0.3-0.95) if the treatment had started ≥ 8 weeks. In the hematogenous group, 5 of 6 infections had been treated successfully. A longer delay before the start of the treatment caused an increased failure rate, but this must be weighed against the advantage of keeping the prosthesis. We consider a failure rate of < 50% to be acceptable, and we therefore advocate keeping the prosthesis for up to 8 weeks postoperatively, and in hematogenous infections with a short duration of symptoms.

The interaction between clothing and air weapon pellets.

PubMed

Wightman, G; Wark, K; Thomson, J

2015-01-01

Comparatively few studies have been carried out on air weapon injuries yet there are significant number of injuries and fatalities caused by these low power weapons because of their availability and the public perception that because they need no licence they are assumed to be safe. In this study ballistic gel was tested by Bloom and rupture tests to check on consistency of production. Two series of tests were carried out firing into unclothed gel blocks and blocks loosely covered by different items of clothing to simulate attire (tee shirt, jeans, fleece, and jacket). The damage to the clothing caused by different shaped pellets when fired at different ranges was examined. The apparent hole size was affected by the shape of pellet (round, pointed, flat and hollow point) and whether damage was predominantly caused by pushing yarn to one side or by laceration of the yarn through cutting or tearing. The study also compared penetration into clothed gel and unclothed gel under identical conditions, and loose clothing greatly reduced penetration. With loose clothing at 9.1 m range clothing reduced penetration to 50-70% of the penetration of unclothed gel but at 18.3m range only 7 out of 36 shots penetrated the gel. This cannot be accounted for by the energy loss at the longer range (3-7% reduction from 9.1 m to 18.3 m range in unclothed gels) and it is suggested that impulse may have a role to play. Shots that did not penetrate the gel were used to estimate the possible stopping time for the pellet (around 75 μs) and force (1700 N) or stress (100 MPa) required to bring the pellet to a halt. Even with these low energy projectiles, cloth fibres were entrained in the gel showing the potential for penetration of the body and subsequent infection. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Adipose-derived stem cells cultivated on electrospun l-lactide/glycolide copolymer fleece and gelatin hydrogels under flow conditions - aiming physiological reality in hypodermis tissue engineering.

PubMed

Gugerell, Alfred; Neumann, Anne; Kober, Johanna; Tammaro, Loredana; Hoch, Eva; Schnabelrauch, Matthias; Kamolz, Lars; Kasper, Cornelia; Keck, Maike

2015-02-01

Generation of adipose tissue for burn patients that suffer from an irreversible loss of the hypodermis is still one of the most complex challenges in tissue engineering. Electrospun materials with their micro- and nanostructures are already well established for their use as extracellular matrix substitutes. Gelatin is widely used in tissue engineering to gain thickness and volume. Under conventional static cultivation methods the supply of nutrients and transport of toxic metabolites is controlled by diffusion and therefore highly dependent on size and porosity of the biomaterial. A widely used method in order to overcome these limitations is the medium perfusion of 3D biomaterial-cell-constructs. In this study we combined perfusion bioreactor cultivation techniques with electrospun poly(l-lactide-co-glycolide) (P(LLG)) and gelatin hydrogels together with adipose-derived stem cells (ASCs) for a new approach in soft tissue engineering. ASCs were seeded on P(LLG) scaffolds and in gelatin hydrogels and cultivated for 24 hours under static conditions. Thereafter, biomaterials were cultivated under static conditions or in a bioreactor system for three, nine or twelve days with a medium flow of 0.3ml/min. Viability, morphology and differentiation of cells was monitored. ASCs seeded on P(LLG) scaffolds had a physiological morphology and good viability and were able to migrate from one electrospun scaffold to another under flow conditions but not migrate through the mesh. Differentiated ASCs showed lipid droplet formations after 21 days. Cells in hydrogels were viable but showed rounded morphology. Under flow conditions, morphology of cells was more diffuse. ASCs could be cultivated on P(LLG) scaffolds and in gelatin hydrogels under flow conditions and showed good cell viability as well as the potential to differentiate. These results should be a next step to a physiological three-dimensional construct for soft tissue engineering and regeneration. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Genetic factors controlling wool shedding in a composite Easycare sheep flock.

PubMed

Matika, O; Bishop, S C; Pong-Wong, R; Riggio, V; Headon, D J

2013-12-01

Historically, sheep have been selectively bred for desirable traits including wool characteristics. However, recent moves towards extensive farming and reduced farm labour have seen a renewed interest in Easycare breeds. The aim of this study was to quantify the underlying genetic architecture of wool shedding in an Easycare flock. Wool shedding scores were collected from 565 pedigreed commercial Easycare sheep from 2002 to 2010. The wool scoring system was based on a 10-point (0-9) scale, with score 0 for animals retaining full fleece and 9 for those completely shedding. DNA was sampled from 200 animals of which 48 with extreme phenotypes were genotyped using a 50-k SNP chip. Three genetic analyses were performed: heritability analysis, complex segregation analysis to test for a major gene hypothesis and a genome-wide association study to map regions in the genome affecting the trait. Phenotypes were treated as a continuous or binary variable and categories. High estimates of heritability (0.80 when treated as a continuous, 0.65-0.75 as binary and 0.75 as categories) for shedding were obtained from linear mixed model analyses. Complex segregation analysis gave similar estimates (0.80 ± 0.06) to those above with additional evidence for a major gene with dominance effects. Mixed model association analyses identified four significant (P < 0.05) SNPs. Further analyses of these four SNPs in all 200 animals revealed that one of the SNPs displayed dominance effects similar to those obtained from the complex segregation analyses. In summary, we found strong genetic control for wool shedding, demonstrated the possibility of a single putative dominant gene controlling this trait and identified four SNPs that may be in partial linkage disequilibrium with gene(s) controlling shedding. © 2013 University of Edinburgh, Animal Genetics © 2013 Stichting International Foundation for Animal Genetics.

Measurement of phenotypic resilience to gastro-intestinal nematodes in Merino sheep and association with resistance and production variables.

PubMed

Kelly, Gareth A; Kahn, Lewis P; Walkden-Brown, Stephen W

2013-03-31

A cross-over experiment was conducted to compare six different phenotypic measures of resilience to gastro-intestinal nematodes (predominantly Haemonchus contortus) in Merino sheep and their association with resistance and production levels. On each of six farms, 120 ewes born in 2006 and 120 older mixed age ewes were selected at shearing in 2007. Of these, 60 in each mob were serially treated with long-acting anthelmintics to suppress worm populations. The other 60 ewes were managed according to management practices employed on the farm (infected, INF). At shearing in 2008, the experimental sheep had their anthelmintic treatments switched. The experiment concluded at shearing in 2009. Measures of resilience were greasy fleece weight (GFW), live weight gain (LWG) and haematocrit (HCT) when infected and the difference in these variables between infected and suppressed. Resistance was determined from multiple faecal worm egg counts (WEC) when infected. Measures of resilience based on GFW, LWG and HCT were moderately correlated with each other (r=0.25-0.50) suggesting that they represent different traits. Correlations between a measure in infected animals, and the difference in the same measurement between infected and uninfected animals were higher (r=-0.37 to -0.82), indicating that measurement during infection is an adequate measure of resilience. WEC was negatively correlated with LWG and HCT during infection but not GFW. Correlations with resilience measures based on difference between infected and uninfected were positive. Surviving infected sheep were found to have higher haematocrit (HCT), and lower WEC in summer and autumn than sheep that died following the measurement. These results show that measurement of performance traits while infected is a reasonable approximation of measurement of resilience based on the difference in performance between infected and non-infected. They also show that resilience to worm infection is not a single trait, but rather a suite of moderately correlated traits. Copyright © 2012 Elsevier B.V. All rights reserved.

The “ram effect”: new insights into neural modulation of the gonadotropic axis by male odors and socio-sexual interactions

PubMed Central

Fabre-Nys, Claude; Kendrick, Keith M.; Scaramuzzi, Rex J.

2015-01-01

Reproduction in mammals is controlled by the hypothalamo-pituitary-gonadal (HPG) axis under the influence of external and internal factors such as photoperiod, stress, nutrition, and social interactions. Sheep are seasonal breeders and stop mating when day length is increasing (anestrus). However, interactions with a sexually active ram during this period can override the steroid negative feedback responsible for the anoestrus state, stimulate luteinizing hormone (LH) secretion and eventually reinstate cyclicity. This is known as the “ram effect” and research into the mechanisms underlying it is shedding new light on HPG axis regulation. The first step in the ram effect is increased LH pulsatile secretion in anestrus ewes exposed to a sexually active male or only to its fleece, the latter finding indicating a “pheromone-like” effect. Estradiol secretion increases in all ewes and this eventually induces a LH surge and ovulation, just as during the breeding season. An exception is a minority of ewes that exhibit a precocious LH surge (within 4 h) with no prior increase in estradiol. The main olfactory system and the cortical nucleus of the amygdala are critical brain structures in mediating the ram effect since it is blocked by their inactivation. Sexual experience is also important since activation (increased c-fos expression) in these and other regions is greatly reduced in sexually naïve ewes. In adult ewes kisspeptin neurons in both arcuate and preoptic regions and some preoptic GnRH neurons are activated 2 h after exposure to a ram. Exposure to rams also activates noradrenergic neurons in the locus coeruleus and A1 nucleus and increased noradrenalin release occurs in the posterior preoptic area. Pharmacological modulation of this system modifies LH secretion in response to the male or his odor. Together these results show that the ram effect can be a fruitful model to promote both a better understanding of the neural and hormonal regulation of the HPG axis in general and also the specific mechanisms by which male cues can overcome negative steroid feedback and trigger LH release and ovulatory cycles. PMID:25914614

Evaluation of Crossbreeding of Australian Superfine Merinos with Gansu Alpine Finewool Sheep to Improve Wool Characteristics

PubMed Central

Li, Fanwen; Niu, Chune

2016-01-01

Crossbreeding of Australian Superfine Merinos (ASMs) with Gansu Alpine Finewool (GAF) sheep and an evaluation of the potential benefits of this genetic cross has not been previously conducted. 13 ASMs were crossbred with GAF sheep over a five year period with backcrossing designed to assess heterosis. Data from 11,178 lambs sired by 189 rams were used in the study. Genotype, birth year, birth type, dam age, sex and/or management group, and record age were fitted as fixed effects and within-genotype sire fitted as a random effect. Crossbreeds of 1/2 ASM expressed the most desirable effects for improving average fiber diameter (AFD), clean fleece weight (CFW), yield, coefficient of variation of AFD (CVAFD), yearling staple length (YSL) to AFD ratio (YSL/AFD), and CFW to metabolic yearling bodyweight (YWT0.75) ratio (CFW/YWT0.75) but showed the least post-weaning average daily gain (powADG) and YWT. Genotype of backcrossing with 1/4 ASM obtained moderate improvements in AFD, CFW, CVAFD, and YSL/AFD but the highest YSL, WWT, and prwADG. Except for yield (-1.42%) and CFW/YWT0.75 (-1%), heterosis estimates were generally low and positive, and ranged from 0.1% for CVAFD to 4% for powADG, which indicates the potential to improve relevant traits through exploiting heterosis to a varying extent. The ASMs sampled in this study were found to be superior to GAFs for AFD, CFW, yield, and CVAFD by 19.82%, 11.68%, 14.47%, and 6.99%, respectively, but inferior for YSL, PowADG, and YWT by 4.36%, 50.97%, and 16.93%, respectively. ASMs also appeared to be more efficient than GAFs in clean wool production (25.34%) and staple length growth (16.17%). The results of our study strongly suggest that an infusion of ASM genes via crossbreeding is an effective and appropriate approach to improve wool microns and wool production from GAF sheep, and we make recommendations to tackle the undesirable traits of YWT and YSL from ASM introduction. PMID:27832155

Shearing at the end of summer affects body temperature of free-living Angora goats ( Capra aegagrus) more than does shearing at the end of winter.

PubMed

Hetem, R S; de Witt, B A; Fick, L G; Fuller, A; Kerley, G I H; Maloney, S K; Meyer, L C R; Mitchell, D

2009-07-01

Angora goats are known to be vulnerable to cold stress, especially after shearing, but their thermoregulatory responses to shearing have not been measured. We recorded activity, and abdominal and subcutaneous temperatures, for 10 days pre-shearing and post-shearing, in 10 Angora goats inhabiting the succulent thicket of the Eastern Cape, South Africa, in both March (late summer) and September (late winter). Within each season, environmental conditions were similar pre-shearing and post-shearing, but September was an average 5°C colder than March. Shearing resulted in a decreased mean (P < 0.0001), minimum (P < 0.0001) and maximum daily abdominal temperature (P < 0.0001). Paradoxically, the decrease in daily mean (P = 0.03) and maximum (P = 0.01) abdominal temperatures, from pre-shearing to post-shearing, was greater in March than in September. Daily amplitude of body temperature rhythm (P < 0.0001) and the maximum rate of abdominal temperature rise (P < 0.0001) increased from pre-shearing to post-shearing, resulting in an earlier diurnal peak in abdominal temperature (P = 0.001) post-shearing. These changes in amplitude, rate of abdominal temperature rise and time of diurnal peak in abdominal temperature suggest that the goats' thermoregulatory system was more labile after shearing. Mean daily subcutaneous temperatures also decreased post-shearing (P < 0.0001), despite our index goat selecting more stable microclimates after shearing in March (P = 0.03). Following shearing, there was an increased difference between abdominal and subcutaneous temperatures (P < 0.0001) at night, suggesting that the goats used peripheral vasoconstriction to limit heat loss. In addition to these temperature changes, mean daily activity increased nearly two-fold after March shearing, but not September shearing. This increased activity after March shearing was likely the result of an increased foraging time, food intake and metabolic rate, as suggested by the increased water influx (P = 0.0008). Thus, Angora goats entered a heat conservation mode after shearing in both March and September. That the transition from the fleeced to the shorn state had greater thermoregulatory consequences in March than in September may provide a mechanistic explanation for Angora goats' vulnerability to cold in summer.

Using Longitudinal Assessment on Extensively Managed Ewes to Quantify Welfare Compromise and Risks

PubMed Central

Barber, Stuart; Hemsworth, Paul; Doyle, Rebecca

2018-01-01

Simple Summary Sheep managed extensively can be exposed to several welfare challenges during the year, and the risk of some diseases can increase in warmer and wetter seasons. In this study, the welfare of Merino ewes was examined over a calendar year. The welfare of these animals, kept on a single farm with consistent management, varied substantially. Overall, the largest number of ewes experienced compromise and risk to welfare at weaning, indicating that this was the most vulnerable time. The main welfare issues identified were under and over feeding, ewe mortality, lameness, ecto-parasites (flystrike) and mastitis, all of which could be improved by modifying management practices, such as improved nutritional management and monitoring and better tail docking procedures. Future research must consider that significant variation in the on-farm welfare of ewes occurs during a calendar year, which needs to be accounted for when conducting on-farm assessments. Abstract This study examined variation in the welfare of extensively managed ewes and potential welfare risks. A total of 100 Merino ewes (aged 2–4 years) were individually identified and examined at three key stages: pregnancy, lactation and weaning. Eight animal-based welfare measures were used to assess welfare: flight distance, body condition score (BCS), fleece condition, skin lesions, tail length, dag score, lameness and mastitis. Data were analysed by ANOVA and McNemar’s statistics. Overall, the average BCS of the group was in agreement with industry recommendations. However, a number of animals were classified with inadequate condition (either too thin or too fat) across the three observation periods. The presence of heavy dags was greatest at mid-lactation (87%, P < 0.0001), lameness was greatest at weaning (14%, P = 0.01), clinical mastitis was 1% annually, and five ewes were lost from the study. Ewes had better health at mid-pregnancy compared to mid-lactation and weaning. The main welfare issues identified were under and over feeding, ewe mortality, lameness, ecto-parasites (flystrike) and mastitis, all of which have the potential to be reduced with improved management practices. Future welfare assessment programs must consider that significant variation in on-farm welfare will occur in extensively managed systems and this needs to be accounted for when evaluating farms. PMID:29316704

Comparative Transcriptome Analysis of Fetal Skin Reveals Key Genes Related to Hair Follicle Morphogenesis in Cashmere Goats.

PubMed

Gao, Ye; Wang, Xiaolong; Yan, Hailong; Zeng, Jie; Ma, Sen; Niu, Yiyuan; Zhou, Guangxian; Jiang, Yu; Chen, Yulin

2016-01-01

Cashmere goat skin contains two types of hair follicles (HF): primary hair follicles (PHF) and secondary hair follicles (SHF). Although multiple genetic determinants associated with HF formation have been identified, the molecules that determine the independent morphogenesis of HF in cashmere goats remain elusive. The growth and development of SHF directly influence the quantity and quality of cashmere production. Here, we report the transcriptome profiling analysis of nine skin samples from cashmere goats using 60- and 120-day-old embryos (E60 and E120, respectively), as well as newborns (NB), through RNA-sequencing (RNA-seq). HF morphological changes indicated that PHF were initiated at E60, with maturation from E120, while differentiation of SHF was identified at E120 until formation of cashmere occurred after birth (NB). The RNA-sequencing analysis generated over 20.6 million clean reads from each mRNA library. The number of differentially expressed genes (DEGs) in E60 vs. E120, E120 vs. NB, and E60 vs. NB were 1,024, 0 and 1,801, respectively, indicating that no significant differences were found at transcriptomic levels between E120 and NB. Key genes including B4GALT4, TNC, a-integrin, and FGFR1, were up-regulated and expressed in HF initiation from E60 to E120, while regulatory genes such as GPRC5D, PAD3, HOXC13, PRR9, VSIG8, LRRC15, LHX2, MSX-2, and FOXN1 were up-regulated and expressed in HF keratinisation and hair shaft differentiation from E120 and NB to E60. Several genes belonging to the KRT and KRTAP gene families were detected throughout the three HF developmental stages. The transcriptional trajectory analyses of all DEGs indicated that immune privilege, glycosaminoglycan biosynthesis, extracellular matrix receptor interaction, and growth factor receptors all played dominant roles in the epithelial-mesenchymal interface and HF formation. We found that the Wnt, transforming growth factor-beta/bone morphogenetic protein, and Notch family members played vital roles in HF differentiation and maturation. The DEGs we found could be attributed to the generation and development of HF, and thus will be critically important for improving the quantity and quality of fleece production in animals for fibres.

Genetic selection, sex and feeding treatment affect the whole-body chemical composition of sheep.

PubMed

Lewis, R M; Emmans, G C

2007-11-01

Hypotheses on total body chemical composition were tested using data from 350 Suffolk sheep grown to a wide range of live weights, and fed in a non-limiting way, or with reduced amounts of feed, or ad libitum on feeds of reduced protein content. The sheep were from an experiment where selection used an index designed to increase the lean deposition rate while restricting the fat deposition rate. Ultrasound muscle and fat depths were the only composition measurements in the index. The animals were males and females from a selection (S) line and its unselected control (C). The protein content of the lipid-free dry matter was unaffected by live weight, sex or feeding treatment with only a very small effect of genetic line (0.762 kg/kg in S and 0.753 kg/kg in C; P < 0.05). The form of the relationship between water and protein was not affected by any of the factors; in the different kinds of sheep it was consistent with no effect other than through differences in mature protein weight. The water : protein ratio at maturity was estimated as 3.45. Over the whole dataset, lipid weight (L) increased with protein weight (P) according to L = 0.3135 × P1.850. Allowing for this scaling, fatness increased on low-protein feeds, was greater in females than in males and in C than in S (P < 0.001). Lipid content (g/kg fleece-free empty body weight) was reduced by restricted feeding only in males at the highest slaughter weight (114 kg). The lines differed in lipid content (P < 0.001) with means of 265.1 g/kg for C and 237.3 g/kg for S. Importantly, there was no interaction between line and feeding treatments. A higher proportion of total body protein was in the carcass in S than in C (0.627 v. 0.610; P < 0.001). For lipid, the difference was reversed (0.736 v. 0.744; P < 0.05). The total energy content increased quadratically with slaughter weight. At a particular weight, the energy content of gain was higher in females than in males and in C than in S. Genetic selection affected body composition at a weight favouring the distribution of protein to the carcass and lipid to the non-carcass. Once allowing for effects of genetic selection, sex and feeding treatment on fatness, simple rules can be used to generate the chemical composition of sheep.

Genetic correlations between wool traits and meat quality traits in Merino sheep.

PubMed

Mortimer, S I; Hatcher, S; Fogarty, N M; van der Werf, J H J; Brown, D J; Swan, A A; Jacob, R H; Geesink, G H; Hopkins, D L; Edwards, J E Hocking; Ponnampalam, E N; Warner, R D; Pearce, K L; Pethick, D W

2017-10-01

Genetic correlations between 29 wool production and quality traits and 25 meat quality and nutritional value traits were estimated for Merino sheep from an Information Nucleus (IN). Genetic correlations among the meat quality and nutritional value traits are also reported. The IN comprised 8 flocks linked genetically and managed across a range of sheep production environments in Australia. The wool traits included over 5,000 yearling and 3,700 adult records for fleece weight, fiber diameter, staple length, staple strength, fiber diameter variation, scoured wool color, and visual scores for breech and body wrinkle. The meat quality traits were measured on samples from the and included over 1,200 records from progeny of over 170 sires for intramuscular fat (IMF), shear force of meat aged for 5 d (SF5), 24 h postmortem pH (pHLL; also measured in the , pHST), fresh and retail meat color and meat nutritional value traits such as iron and zinc levels, and long-chain omega-3 and omega-6 polyunsaturated fatty acid levels. Estimated heritabilities for IMF, SF5, pHLL, pHST, retail meat color lightness (), myoglobin, iron, zinc and across the range of long-chain fatty acids were 0.58 ± 0.11, 0.10 ± 0.09, 0.15 ± 0.07, 0.20 ± 0.10, 0.59 ± 0.15, 0.31 ± 0.09, 0.20 ± 0.09, 0.11 ± 0.09, and range of 0.00 (eicosapentaenoic, docosapentaenoic, and arachidonic acids) to 0.14 ± 0.07 (linoleic acid), respectively. The genetic correlations between the wool production and meat quality traits were low to negligible and indicate that wool breeding programs will have little or no effect on meat quality. There were moderately favorable genetic correlations between important yearling wool production traits and the omega-3 fatty acids that were reduced for corresponding adult wool production traits, but these correlations are unlikely to be important in wool/meat breeding programs because they have high SE, and the omega-3 traits have little or no genetic variance. Significant genetic correlations among the meat quality traits included IMF with SF5 (-0.76 ± 0.24), fresh meat color * (0.50 ± 0.18), and zinc (0.41 ± 0.19). Selection to increase IMF will improve meat tenderness and color which may address some of the issues with Merino meat quality. These estimated parameters allow Merino breeders to combine wool and meat objectives without compromising meat quality.

Breeding objectives for sheep should be customised depending on variation in pasture growth across years.

PubMed

Rose, G; Mulder, H A; Thompson, A N; van der Werf, J H J; van Arendonk, J A M

2015-08-01

Breeding programmes for livestock require economic weights for traits that reflect the most profitable animal in a given production system, which affect the response in each trait after selection. The profitability of sheep production systems is affected by changes in pasture growth as well as grain, meat and wool prices between seasons and across years. Annual pasture growth varies between regions within Australia's Mediterranean climate zone from low growth with long periods of drought to high growth with shorter periods of drought. Therefore, the objective of this study was to assess whether breeding objectives need to be adapted for regions, depending on how reliable the pasture growth is across years. We modelled farms with Merino sheep bred for wool and meat in 10 regions in Western Australia. Across these 10 regions, mean annual pasture growth decreased, and the CV of annual pasture growth increased as pasture growth for regions became less reliable. We calculated economic values for nine traits, optimising management across 11 years, including variation for pasture growth and wool, meat and grain prices between and within years from 2002 to 2012. These economic values were used to calculate responses to selection for each trait for the 10 regions. We identified two potential breeding objectives, one for regions with low or high reliability and the other for regions with medium reliability of pasture growth. Breeding objectives for high or low pasture growth reliability had more emphasis on live weight traits and number of lambs weaned. Breeding objectives for medium reliability of pasture growth had more emphasis on decreasing fibre diameter. Relative economic weights for fleece weight did not change across the regions. Regions with low or high pasture reliability had similar breeding objectives and response to selection, because the relationship between the economic values and CV of pasture growth were not linear for live weight traits and the number of lambs weaned. This non-linearity was caused by differences in distribution of pasture growth between regions, particularly during summer and autumn, when ewes were pregnant, with increases in energy requirements affecting the value of lambs weaned. In addition, increasing live weight increased the intake capacity of sheep, which meant that more poor quality pasture could be consumed during summer and autumn, which had more value in regions with low and high pasture reliability. We concluded that breeding values for sheep production systems should be customised depending on the reliability of pasture growth between years.

From Scientist to Educator: Oceanography in the Formal and Informal Classroom

NASA Astrophysics Data System (ADS)

Richardson, A. H.; Jasnow, M.; Srinivasan, M. S.; Rosmorduc, V.; Blanc, F.

2002-12-01

The TOPEX/Poseidon and Jason-1 ocean altimeter missions offer the educator in the middle school or informal education venue a unique opportunity for reinforcing ocean science studies. Two new educational posters from the United States' NASA/Jet Propulsion Laboratory and France's Centre National d'Etudes Spatiales provide teachers and students a tool to examine topics such as the dynamics of ocean circulation, ocean research, and the oceans role in climate. "Voyage on the High Seas; A Jason-1 Oceanic Adventure" is a poster/board game that offers learning opportunities through a non-textbook activity designed to stimulate interest in ocean science in a fun and instructive environment. The object of the game is to be the first to sail your research vessel from the Mediterranean Sea to Seattle, Washington while gaining Discovery Points. The starting point in the Mediterranean is where the mythological adventurers Jason and the Argonauts set out on their epic voyage to find the golden fleece. Discovery and Quiz Cards are used to challenge players to gain knowledge and points by correctly answering questions using clues from the board. Teachers can directly photocopy additional activities from the reverse side of the board game for use in a middle school Earth science curriculum. The game is also a stand-alone poster that is an engaging world map depicting the world's oceans and continents, major ocean currents, and other important geographic features. A second poster has been developed as a joint JPL/CNES effort. "Oceans' Music: Climate's Dance" highlights the ocean/climate link and provides educational activities that can be used directly in the classroom. The eye-catching poster is appropriate for display in both the formal and informal education setting. In both venues it should stimulate conversation about the ocean and provide a point of entry into inquiry-based learning about the connections between ocean circulation and global climate. It also seeks to emphasize the role of the ocean in sustaining life on Earth. Activities on the back of the poster can be used as supplemental material in a middle school Earth science curriculum, and are suitable for individual instruction and for classroom or group exercises. This poster will be published in both English and French. Educational research indicates that an inquiry-based method of student engagement is an appropriate and effective teaching tool. These posters offer a fun and instructive environment to promote student interest in Earth Science in general and particularly in oceanography.

Effects of nutritionally induced metabolic acidosis with or without glutamine infusion on acid-base balance, plasma amino acids, and plasma nonesterified fatty acids in sheep.

PubMed

Odongo, N E; Greenwood, S L; Or-Rashid, M M; Radford, D; Alzahal, O; Shoveller, A K; Lindinger, M I; Matthews, J C; McBride, B W

2009-03-01

This study characterized the effects of nutritionally induced metabolic acidosis with or without Gln infusion on acid-base balance, plasma AA, and plasma NEFA in sheep. In a randomized complete block design with a 2 x 2 factorial arrangement of treatments, 24 fully fleeced sheep (Rideau-Arcott, 63.6 +/- 5.9 kg of BW) were fed a control supplement (CS; 300 g/d of canola meal) or an acidosis supplement (AS; 300 g/d of NutriChlor; HCl-treated canola meal), offered twice daily at 0700 and 1100 h. Sheep were infused at 1400 h daily with 0.3 g of L-glutamine per kg of BW or saline via jugular vein catheters for 7 d. The sheep were individually housed and limit-fed a basal diet of dehydrated alfalfa pellets (1.75 kg/d; 90% DM, 22% CP, and 1.2 Mcal of NE(g)/kg on a DM basis) offered twice daily at 1000 and 1300 h. Blood and urine was sampled daily between 1100 and 1130 h, and blood samples were analyzed for hematocrit, plasma pH, gases, strong ions, AA, and NEFA, whereas urine was analyzed for pH. The AS reduced (P < 0.01) DMI, urine and plasma pH, blood urea, partial pressure of CO(2), strong ion difference, and plasma HCO(3)(-), and increased (P < 0.01) plasma K(+), Ca(2+), and Cl(-). The AS with saline infusion increased (P

Importance of birthcoat for lamb survival and growth in the Romane sheep breed extensively managed on rangelands.

PubMed

Allain, D; Foulquié, D; Autran, P; Francois, D; Bouix, J

2014-01-01

The Romane sheep breed proved to be adapted to harsh conditions with high prolificacy and lamb survival in outdoor farming, even under bad climate conditions. This breed shows large variability in its fleece type at birth and it has been suggested that lamb survival could be related to birthcoat type. The aim of the present study was to: i) characterize the coat of the lamb at birth and quantify lamb survival in relation to the birthcoat type and its protective properties concerning heat loss in the Romane breed raised under permanent exposure outdoors from birth, and ii) estimate genetic parameters of birthcoat type in relation to lamb survival and live body weight. A total of 7,880 lambs from 104 sires and 1,664 dams were used in a 14-yr experiment. The pedigree file included 9,625 individuals over 15 generations. Birthcoat type, coat surface temperature, coat depth, lamb survival, and growth were measured from birth to weaning. Weather data (temperature, wind speed, relative humidity, and precipitation) were recorded daily during lambing time. Two types of coats were observed at birth: hairy coat (62.9% of lambs) with a long coat depth (average 23.3 mm) or woolly 1 (37.1% of lambs) with a short coat depth (average 8.3 mm). Birthcoat type was an important factor affecting lamb survival and growth from birth in the Romane breed. Total mortality rate was significantly less in hairy-bearing coat lambs than in short-woolly coat ones: 7.0% vs. 9.6%, 11.6 % vs. 14.8%, and 15.7 % vs. 20.1 % at 2, 10, and 50 d, respectively, and the relative risks of death increased by 37%, 67%, and 46 % at 2, 10, and 50 d of age, respectively, in short-woolly lambs. At birth, a significant lower coat surface temperature, indicating less heat loss, was observed in long-hairy coat lambs compared with others (21.1°C vs. 26.1°C). Heavier body weights and better growth performances up to the age of 50 d were observed in long-hairy-bearing coat lambs. Lamb survival was positively correlated to weather conditions at lambing time in short-woolly lambs, whereas no relation was observed in hairy-coat lambs. Heritability estimate of birthcoat type (hairy or woolly) is high (0.88). Genetic correlations between birthcoat type, lamb survival, and live body weight at birth were positive and moderate, suggesting that it would be beneficial to take birthcoat into account as an adaptive trait in any genetic strategies for sheep production in harsh conditions on rangelands.

Ash storms: impacts of wind-remobilised volcanic ash on rural communities and agriculture following the 1991 Hudson eruption, southern Patagonia, Chile

NASA Astrophysics Data System (ADS)

Wilson, T. M.; Cole, J. W.; Stewart, C.; Cronin, S. J.; Johnston, D. M.

2011-04-01

Tephra fall from the August 1991 eruption of Volcán Hudson affected some 100,000 km2 of Patagonia and was almost immediately reworked by strong winds, creating billowing clouds of remobilised ash, or `ash storms'. The immediate impacts on agriculture and rural communities were severe, but were then greatly exacerbated by continuing ash storms. This paper describes the findings of a 3-week study tour of the diverse environments of southern Patagonia affected by ash storms, with an emphasis on determining the impacts of repeated ash storms on agriculture and local practices that were developed in an attempt to mitigate these impacts. Ash storms produce similar effects to initial tephra eruptions, prolonged for considerable periods. These have included the burial of farmland under dune deposits, abrasion of vegetation and contamination of feed supplies with fine ash. These impacts can then cause problems for grazing animals such as starvation, severe tooth abrasion, gastrointestinal problems, corneal abrasion and blindness, and exhaustion if sheep fleeces become laden with ash. In addition, ash storms have led to exacerbated soil erosion, human health impacts, increased cleanup requirements, sedimentation in irrigation canals, and disruption of aviation and land transport. Ash deposits were naturally stabilised most rapidly in areas with high rainfall (>1,500 mm/year) through compaction and enhanced vegetation growth. Stabilisation was slowest in windy, semi-arid regions. Destruction of vegetation and suppression of regrowth by heavy tephra fall (>100 mm) hindered the stabilisation of deposits for years, and reduced the surface friction which increased wind erosivity. Stabilisation of tephra deposits was improved by intensive tillage, use of windbreaks and where there was dense and taller vegetative cover. Long-term drought and the impracticality of mixing ash deposits with soil by tillage on large farms was a barrier to stabilising deposits and, in turn, agricultural recovery. The continuing ash storms motivated the partial evacuation of small rural towns such as Chile Chico (Chile) and Los Antiguos (Argentina) in September-December 1991, after the primary tephra fall in August 1991. Greatly increased municipal cleanup efforts had to be sustained beyond the initial tephra fall to cope with the ongoing impacts of ash storms. Throughout the 1990s, ash storms contributed to continued population migration out of the affected area, leaving hundreds of farms abandoned on the Argentine steppe. The major lesson from our study is the importance of stabilisation of ash deposits as soon as possible after the initial eruption, particularly in windy, arid climates. Suggested mitigation measures include deep cultivation of the ash into the soil and erecting windbreaks.

Geochronology and geology of late Oligocene through Miocene volcanism and mineralization in the western San Juan Mountains, Colorado

USGS Publications Warehouse

Bove, D.J.; Hon, Ken; Budding, K.E.; Slack, J.F.; Snee, L.W.; Yeoman, R.A.

2000-01-01

Twenty-five new 40Ar/39Ar ages from volcanic rocks and veins in the western San Juan Mountains clarify relationships between volcanism and mineralization in this classic area. Five calc-alkaline ash-flow sheets erupted from caldera sources (Ute Ridge, Blue Mesa, Dillon Mesa, Sapinero Mesa, and Crystal Lake Tuffs) from 28.6 to 27.6 Ma. This is a much more restricted time interval than previously thought and indicates that the underlying batholith rose and evolved very rapidly beneath the western San Juan Mountains. The new ages and geologic relations constrain the timing of joint resurgence of the Uncompahgre and San Juan calderas to between 28.2 and 27.6 Ma. The collapse of the Silverton caldera produced a set of strong ring fractures that intersected with graben faults on the earlier resurgent dome to produce the complex set of structures that localized the mid-Miocene epithermal gold veins. Later calc-alkaline monzonitic to quartz monzontic plutons solidified at 26.5-26.0 Ma as the underlying batholith rose through its volcanic cover. A new age from lavas near Uncompahgre Peak supports earlier interpretations that these lavas were fed by nearby 26 Ma monzonite intrusions. Nearly all of these intrusions are associated with subeconomic Mo and Cu mineralization and associated alteration, and new ages of 26.40 and 25.29 Ma from the Ute-Ulay and Lilly veins in the Lake City region show that some of the most important silver and base-metal veins were temporally and possibly genetically connected to these plutons. In addition, the Golden Fleece telluride vein cuts all of the post-Uncompahgre caldera volcanics in the area and is probably temporally related to this cycle, though its age of 27.5 ? 0.3 Ma was determined by less precise U/Pb methods. The 22.9 Ma Lake City caldera collapsed within the older Uncompahgre caldera structure but is petrologically unrelated to the older calc-alkaline activity. The distinctive suite of high-silica rhyolite tuff and alkaline resurgent intrusions indicates that it is closely related to the early stages of bimodal high-silica rhyolite-alkali basalt volcanism that accompanied the onset of extensional tectonism in the region. Both 40Ar/39Ar ages and paleomagnetic data confirm that the entire caldera sequence formed in less than 330,000 years. Only weak quartz vein mineralization is present in the center of the caldera, and it appears to be related to leaching of metals from the intracaldera tuffs above the resurgent intrusion. Massive alunitization and weak Mo and Cu mineralization along the eastern ring fracture are associated with calc-alkaline lavas and stocks related to late stages of the caldera cycle. These calc-alkaline stocks also appear to be genetically and temporally linked to a radial pattern of barite-precious metal veins on the northeastern margin of the Lake City caldera.

Risk factors for postoperative CSF leakage after elective craniotomy and the efficacy of fleece-bound tissue sealing against dural suturing alone: a randomized controlled trial.

PubMed

Hutter, Gregor; von Felten, Stefanie; Sailer, Martin H; Schulz, Marianne; Mariani, Luigi

2014-09-01

Cerebrospinal fluid leakage is an immanent risk of cranial surgery with dural opening. Recognizing the risk factors for this complication and improving the technique of dural closure may reduce the associated morbidity and its surgical burden. The aim of this paper was to investigate whether the addition of TachoSil on top of the dural suture reduces postoperative CSF leakage compared with dural suturing alone and to assess the frequency and risk factors for dural leakage and potentially related complications after elective craniotomy. The authors conducted a prospective, randomized, double-blinded single-center trial in patients undergoing elective craniotomy with dural opening. They compared their standard dural closure by running suture alone (with the use of a dural patch if needed) to the same closure with the addition of TachoSil on top of the suture. The primary end point was the incidence of CSF leakage, defined as CSF collection or any open CSF fistula within 30 days. Secondary end points were the incidence of infection, surgical revision, and length of stay in the intensive care unit (ICU) or intermediate care (IMC) unit. The site of craniotomy, a history of diabetes mellitus, a diagnosis of meningioma, the intraoperative need of a suturable dural substitute, and blood parameters were assessed as potential risk factors for CSF leakage. The authors enrolled 241 patients, of whom 229 were included in the analysis. Cerebrospinal fluid leakage, mostly self-limiting subgaleal collections, occurred in 13.5% of patients. Invasive treatment was performed in 8 patients (3.5%) (subgaleal puncture in 6, lumbar drainage in 1, and surgical revision in 1 patient). Diabetes mellitus, a higher preoperative level of C-reactive protein (CRP), and the intraoperative need for a dural patch were positively associated with the occurrence of the primary end point (p = 0.014, 0.01, and 0.049, respectively). Cerebrospinal fluid leakage (9.7% vs 17.2%, OR 0.53 [95% CI 0.23-1.15], p = 0.108) and infection (OR 0.18 [95% CI 0.01-1.18], p = 0.077) occurred less frequently in the study group than in the control group. TachoSil significantly reduced the probability of staying in the IMC unit for 1 day or longer (OR 0.53 [95% CI 0.27-0.99], p = 0.048). Postoperative epidural hematoma and empyema occurred in the control group but not in the study group. Dural leakage after elective craniotomy/durotomy occurs more frequently in association with diabetes mellitus, elevated preoperative CRP levels, and the intraoperative need of a dural patch. This randomized controlled trial showed no statistically significant reduction of postoperative CSF leakage and surgical site infections upon addition of TachoSil on the dural suture, but there was a significant reduction in the length of stay in the IMC unit. Dural augmentation with TachoSil was safe and not related to adverse events. Clinical trial registration no. NCT00999999 ( http://www.ClinicalTrials.gov ).

hwhap_Ep30_Infamous Meteorites

NASA Image and Video Library

2018-02-01

Gary Jordan (Host): Houston, We Have A Podcast. Welcome to the official podcast of the NASA Johnson Space Center, Episode 30, Infamous Meteorites. I'm Gary Jordan, and I'll be your host today. So on this podcast, we bring in the experts, NASA scientists, engineers, astronauts, all to let you know the coolest stuff about what's going on right here at NASA. So today, we're talking about some of the more unique findings that have been discovered in meteorites with David Mittlefehldt, goes by Duck. He's a planetary scientist here at the NASA Johnson Space Center in Houston, Texas, and we had a great discussion about curious findings in meteorites, and the adventures that are endured to procure them. So, with no further delay, let's go lightspeed and jump right ahead to our talk with Dr. Duck Mittlefehldt. Enjoy! [ Music & Radio Transmissions ] Host: Duck, thanks for coming to the podcast today. I know we've -- we've talked about searching for life and meteorites before, and it's -- it's such a fascinating topic, but I really wanted to dive deeper, just into like the meteorites portion. We really -- we really actually had a great conversation with Dr. Aaron Burton and -- and Dr. Marc Fries, not too long ago, actually, about life, but really just about the meteorites themselves. There's a -- there's a big story there, and you're one of the explorers that are going down and actually finding these meteorites, huh? Dr. Duck Mittlefehldt: Yeah, yeah. I've done that on a number of occasions. Host: Yeah. And it's -- is it -- is it mostly in Antarctica, or are you going other places? Dr. Duck Mittlefehldt: Well, okay, so most of the times I've been searching for meteorites has been in Antarctica, so I've been down there five times, meteorite collecting expeditions, but I -- I've [pause] -- I was on vacation in Israel once, and I met up with a couple of geologists at a coffee house, and one of them had just published a paper where they -- he described, you know, old surfaces in the deserts of southern Israel that are, you know, have been stable for about 2 million years. And I'm thinking, you know, over 2 million years, you can accumulate a lot of meteorites, so, I actually went there the foll -- later that year, and met up with them again, and we searched some of these areas that are -- have very ancient pavements on the desert, and hunting for meteorites. We didn't find any, unfortunately, and, you know, I'm not quite sure why, there -- there should have been some there, but, you know, it was a small team searching large area over short time, so it may well be that they're there, but we just didn't find any, because the ones that, you know, are there are small. The other is there were a number of issues with that particular location. Meteorites, you know, when we find meteorites, they're typically black on the outside, because they've gone through the atmosphere and they're covered with this glassy, fusion crust, which is almost always black. The area we had searched in southern Israel actually had a number of dark rocks in it, as well. So, you know, the meteorites, if they were there, would not have stood out as -- like -- like, you know, the beacons that you see when you're in Antarctica, scooting across the bare ice, so. Host: I guess that -- is that the main reason why Antarctica is such a great place to find meteorites? Is because it's these black rocks against white snow? Dr. Duck Mittlefehldt: Well, that certainly makes it easy, because [Gary laughing] you -- you can see, you know, a rock, I'm going to use metric units because that's what I'm used to, I'll try and remember to throw in inches and feet as I can, but, so, you know, you can find a -- a black rock, a couple of centimeters across or about an inch across, from a great distance in Antarctica on the ice. And -- and, as you say, it's because you're looking at either pale blue ice or sometimes white snow, most of the meteorites we find are on the pale blue ice. But even so, it's very bright in comparison to rock. So they're easy to find there. The other thing is in Antarctica, we have a convenient concentration mechanism, which is the actual flow and ablation of the ice across the continent, and where we go to find them the meteorites is -- is actually in locations where the ice movement has been stalled, and ablation by the Antarctic winds and -- and warming by the Antarctic sun, allow a lag deposit to develop on the surface. So we're actually collecting meteorites that have been, you know, shoved from a great geographic area and then left behind in a smaller geographic area. So we have, you know, base -- we have both the easy-to-spot and -- and the concentration mechanism working in our favor. Host: Alright! Yeah, they're -- they're plentiful down there. So -- so you made quite a few trips. How many was it? You said five? Dr. Duck Mittlefehldt: Yeah, I've been down five times. The first time was in the '97, '98 field season. That was my first Antarctic experience, and I loved it so much I kept volunteering to go back again. Host: You loved Antarctica? Dr. Duck Mittlefehldt: Oh yeah [Gary laughing], I -- I love it, you know, just -- just last week, well, here in Houston, we had temperatures that Houstonians think of, or Texans think of as cold, but, me, I see that as maybe a cold fall day. Because I -- I was born and raised in western New York. Host: Alright. Dr. Duck Mittlefehldt: And at the same time, you know, my hometown was getting temperatures, okay, again, I've got to do some conversion here, about maybe, you know, between 0 and 5 degrees Fahrenheit. And, you know, that was the weather I grew up in winter, and I loved it. Winter was always my favorite season when I was a kid. Alright. So maybe it's a deep love of winter that really -- because I just came from this -- we're just coming back from the holidays now, and it was -- it was negative 2 in Pittsburgh when I -- when I was flying home, and, I mean, I was -- I was born and raised in Pennsylvania, moved around a lot, but I'm not used to it by any means. Like, I like the -- I like the, everyone, you know, saying, oh my gosh, 32 is really cold! And I'm like, [laughing], I'm okay with just that. Host: For me, I -- I loved the deep winter in western New York. Dr. Duck Mittlefehldt: Alright, a lot of snow there too. Host: So when was the last time you were down in Antarctica then? Dr. Duck Mittlefehldt: So I was down last year, 2016, 2017, it was kind of a disappointment for me, personally. Host: Oh. Dr. Duck Mittlefehldt: I -- I -- because of my experience, I've been down four times before, I -- I left early and was going to go out on a recon sweep with the -- the mountaineer field safety officer for the ANSMET program. ANSMET, by the way, stands for Antarctic Search for Meteorites, and that's the program that goes down to collect the rocks and has been doing so every year, but once, since 1976. Host: Alright! Dr. Duck Mittlefehldt: But, anyway, because of my experience, I was going to go down on this recon before the main season. We were going to go to one area, check it out for potential systematic work in a future season, and then stay for the first half of the main season, going to a location deep along the Antarctic, transAntarctic mountains. Well, it turns out logistics were badly broken last year. And partly because of weather, partly because of problems with the aircraft and so on, so I got out into the field for a week, in preseason, I got back to McMurdo Station while we were gearing up for the main season, but the logistics just broke and so they were not going to go out where they originally planned. The team ended up going to where I had been out on recon, but it was -- they got such a late start that it made more sense to ship me home early rather than, you know, go out for maybe a week and then come back into McMurdo and go home. Host: Yeah. Dr. Duck Mittlefehldt: So I -- I just spend one week out in the field last year. Host: Ahh... Dr. Duck Mittlefehldt: Much -- much to my chagrin. Host: [Laughing] So it was just the lack of time that you spent there, that was really the disappointment. Yeah, yeah, it was [inaudible] time, and, you know, in the brief time that John Scott [phonetic] and I, he's the mountaineer, were out on the ice, you know, we -- we'd spend a week in the field, two and a half days we were tent-bound because the weather was so bad, but even so, we found 46 meteorites in the short time we were there. Host: That's amazing! Yeah. Host: Wow. Dr. Duck Mittlefehldt: And -- and remind -- and remember, this was an area that had been heavily harvested back in the 80's, 70's and 80's, we were going to back to see whether there was still great potential for harvesting more meteorites there, and, in fact, I think last year they ended up coming -- picking up a total of 200 and some meteorites, even with, you know, going back to an area that had been searched before, and having a shortened season because the logistics. So, I mean, that -- that kind of shows you the -- the quality of Antarctica as a -- as a site for bringing back space rocks. It's just awesome! Host: Incredible! So is -- is that -- is it because there's just a fresh, I guess you could call it, supply of meteorites that are landing on the surface of Antarctica, or is it things are shifting? Dr. Duck Mittlefehldt: It's more things are shifting. In part, you know, deflation of the surface continues, as ablation goes on, and so new meteorites are poking through. In part, it's shifting winds blowing snow around, so an area that might have been snow covered earlier season, maybe now has been stripped bare and there's bare ice. And so that allows you to see things. So for a variety of reasons, you can go back to the same place you've searched once, and -- and still find meteorites out there. Host: Incredible. And hundreds of them, a little bit better than Israel, right? Dr. Duck Mittlefehldt: Yeah [laughter]. Might have been better than my experience trying to find meteorites in the Negev Desert. Host: [Laughing] So -- so you're saying a season. When you're going down to Antarctica, I'm assuming it's the summer there, right? Dr. Duck Mittlefehldt: Yeah, it's austral summer. Host: Yeah. So that means the sun is up 24/7, right? Dr. Duck Mittlefehldt: Right. Host: So you kind of have to deal with that when you're -- when you're down there, right? Dr. Duck Mittlefehldt: Yeah, you know, I've -- I've become accustomed to that. The first -- I was kind of -- there was a guy who used to work in our building who had been down I think a year or two before me, so I took advice from him, and he said, you know, one of the things is, you know, with the constant sunlight, sometimes sleep can be a problem. So I bought a heavy, black knit hat, and, you know, I just put that on as my sleep hat, and then pulled the brim over my eyes, and so everything was black. So I -- I could sleep fine down there. Host: Oh, nice! Dr. Duck Mittlefehldt: But the, you know, the main advantage is that because the sun's up 24/7, you're not really bound by the 9 to 5 time sequence. Host: Oh, yeah. Dr. Duck Mittlefehldt: So, as I said, when we -- when I was out last year in the -- in the recon site, we were there for a week, you know, we -- we landed, got our gear, and then went, spent a half a day out, then the -- the winds blew in, it was too windy and cold to go out, so the winds broke around noon one day, or a little bit after noon. We decided we would have an early supper and then go out and collect -- harvest meteorites. So that day, we ended up getting out of the tents maybe 5 o'clock in the evening, and we worked about till 30, 2 in the morning. Host: Woah! Dr. Duck Mittlefehldt: The sun was up, it was perfectly fine, it was just my age and body crapping out at 30 [Gary laughing]. I, you know, I just couldn't pick up another meteorite if -- if they beat me with a stick. You know, I was just so tired. But then, you know, that's -- that's something you can do down there that you can't do here. Host: Yeah, did you know the hours were going by, or did you have no sense of time with the -- with the sun being up? Dr. Duck Mittlefehldt: Well, you know, you can trace the sun, if you pay attention, you can get a sense of the day, because the sun does a lazy loop in the sky, and... Host: Oh. Dr. Duck Mittlefehldt:...and so, you know, once you've located yourself, you know where north, south is, [pause] there is still north and south, even that close to the pole. Host: Yeah. Dr. Duck Mittlefehldt: But, you know, you know at midnight, the sun is going to be, you know -- you know, at one -- at the one position, so. Host: Right. Dr. Duck Mittlefehldt: And it's kind of at the lowest point far north, and so, you know, you can track it that way, but basically I didn't pay attention. We were just so busy, you know, driving from place to place harvesting meteorites that, you know, it was just constantly moving, doing the next one, taking the data, collecting it, you know, cleanly and safely and getting it in the bag and moving on to the next location. Host: Oh, so are you -- are you not -- you're not stationary then when you -- when you kind of set up camp. Are you -- are you kind of mobile, like with your camp, and you just move it from one meteorite site? Dr. Duck Mittlefehldt: No, no. Host: Oh, okay. Dr. Duck Mittlefehldt: The camp is usually -- there are a couple -- there are a couple of ways that it is done. When we do systematic searching, the camp is stationary in one spot, perhaps for the whole field season, and you just go out, day-to-day, to different locations. And that's what we did here. We were on recon, so we -- we plunked the tent down, then we searched within easy skidoo range of the camp. Sometimes, and I've done this before, go down on a recon time, where -- where you go and you put camp down, you might prospect an area for two, three weeks, then you move camp to another area and prospect there for two or three weeks. So, there -- there are -- those -- there are those two types of scenarios, and even in the recon mode, you know, you're -- the tent -- the camp is stationary for two or three weeks, and you're skidooing all around that area to -- to search it, and then you only pick up tents and camp and move to a far distant area to recon that general region. Host: Alright! Alright, well I'm guessing, you know, going down there so many times, you're quite an expert in making sure that, you know, you can survive weeks and weeks and weeks in Antarctica. So, what are the -- some of the stuff that you're taking down there that I guess are unique to the Antarctic environment? Dr. Duck Mittlefehldt: Okay, so, most of the gear you get, you get in Christchurch, so, you know, living in Houston, I don't have a winter coat. Host: Oh! Dr. Duck Mittlefehldt: So, at -- at the clothing distribution center in Christchurch, you'll get outkitted -- outfitted with, you know, heavy -- heavy jackets, all the gloves you can want, thermal pants, fleece liners, boots, hats, everything you need to survive, and then in McMurdo Station, you actually get the camping gear, the tents, the cook stoves, the dishes, the food, sleeping bags, that sort of stuff. So all -- all the intrepid Antarctic explorer needs to take down with them are personal items, like I mentioned my knit hat, that -- that was mine, and that was because I knew I wanted something to sleep in. I, you know, I bought extra pairs of thermal underwear, because the first time I went down, you know, they -- they give you two sets, but you're out in the field for six or seven weeks, so you want to change, you know, once in a while. [Gary laughing] Other than that, you know, my glasses are prescription, and so I buy glasses that transition dark and sunlight, so I can just, you know, wear my normal glasses out on the skidoo, I have actually bought glacier glasses, so I have side shields and whatnot to block the light. You want to -- one of the things that really is critical down there is to block all light from your eyeballs, you know, other than what gets filtered through a dark lens, because, otherwise, snow blindness is a problem. Host: Oh, that's right! It's so bright down there, right? Yeah. Dr. Duck Mittlefehldt: So I do that, but, otherwise, you know, most of the gear they give you, they loan it to you for the time that you're out there, and -- and so, you know, you could survive on just what you get from the Antarctic program down in Antarctica. It wouldn't necessarily be entirely comfortable wearing the same clothes, you know, for seven weeks, but you could do it. Host: [Laughing] So -- so your -- this Antarctic program, that -- that's ANSMET, right? Dr. Duck Mittlefehldt: Right. Host: Okay, so what's the -- what's the relationship between ANSMET and NASA, and how that all works together? Dr. Duck Mittlefehldt: Well, originally, ANSMET was set up as a three agency agreement. So the -- the -- it was funded -- the actual Antarctic search for meteorites was funded through the National Science Foundation, because they have -- they do the scientific research in Antarctica. NASA funded the curation and allocation of meteorite samples here at NASA Johnson Space Center, and then the Smithsonian Institution did the initial classification and was the long-term repository for the meteorites collected in Antarctica. That, since -- since then, they've changed it, and now NASA actually funds the Antarctic, the ANSMET research component. NSF still supplies the logistics, but NASA pays NSF for those, those logistics, because they -- they are the, I mean, they have all the logistics in Antarctica. And -- and the rocks still go, ultimately, to the Smithsonian, a chip for initial classification, and rocks that are no longer actively being researched by scientists in the world end up being permanently curated at the Smithsonian Institution. So that is -- that is still the way things are run. Host: Alright. So -- so is the ones that people are researching, and actively studying, are all of them housed here at the Johnson Space Center? Dr. Duck Mittlefehldt: Yes. With some exceptions. We don't have the necessary facilities to easily deal with metal-rich meteorites. So iron meteorites, stony iron meteorites, automatically go, ah, nope, I'm going to pull that back. Iron meteorites automatically go to the Smithsonian Institution. Because they are equipped for -- to cut metal and -- and make samples available. We do do the stony meteorites here, I forgot about that, because I've gotten some from here. So those that have a significant stony component are still worked on here until they become no longer of scientific interest. But, you know, even though they go to the Smithsonian for permanent curation, they're -- they're not dead to science, so to speak. So I can request samples that have been housed at Johnson Space Center for years, and now transfer -- transformed permanently to the Smithsonian if -- if I find, you know, an interesting project to do on one of these old samples. And I actually have gotten, in the past, some samples from the Smithsonian that were originally from the Antarctic collection. Host: Wow. So back in Antarctica, when you're looking at these meteorites and you're trying to, you know, figure out what they are, are they, you know, more stony, more metal-rich, what are you using to -- to look at them, to find out more about them and say, yes, that's a meteorite that I want to get my hands on? How do you know what's the good stuff? Dr. Duck Mittlefehldt: Uh, decades of experience. Host: There you go [laughing]. Dr. Duck Mittlefehldt: So, I, you know, I can look at a rock in Antarctica, and I can already make a preliminary classification. Sometimes I'm wrong, and -- and, you know, the guy who has more experience than anyone is -- is our mountaineer field safety officer, John Scott, and, you know, he -- he can look at a rock, and, in many cases, give a pretty good guess as to what it's going to turn out to be. And, you know, I can do that with a lot of different types of rocks, especially those that I'm interested in, but all in all, there -- there are always those meteorites that come back that either no one has ever seen before, because it's totally new, or it's enough different from the norm for that class that it just doesn't -- doesn't appear to be what you think it is, in hand sample. So, and we don't -- and we don't, you know, in Antarctica, we don't do anymore than a very high-level classification. Yes, this is a stony meteorite, it's probably a chondrite, this is probably a carbonaceous chondrite, this is probably an achondrite, which is a type of meteorite that's been melted. This is probably a stony iron, an iron, and so forth. And, to some extent, we need to do that because certain types of meteorites have more scientific value than others. So -- so, for example, a very primitive carbonaceous chondrite is -- is probably going to get a lot of research attention when it's announced. And so we collect those in a special way to try and minimize contamination by organic compounds. And that's why we need to be able to say, oh, yeah, you know, stand back from this guy, we need to treat him differently than -- than this one over here. Host: Alright. And then, obviously, you know, knowing where to ship it too, right? Because some of the metals one have to go the Smithsonian...? Dr. Duck Mittlefehldt: So that -- no, that's all done here. Everything is shipped here to Johnson Space Center. Host: Oh, everything comes here, okay. Dr. Duck Mittlefehldt: And -- but the difference is when they -- when they open some that are listed in the -- in the notes as probably being iron meteorites, they -- they will warm them up in the dry nitrogen cabinets, look at them, and if they agree, you know, they'll do an external description, you know, this is a brown rock, you know, 10 centimeters in size and weigh so much, and we don't see anything in it, you know, out of the ordinary, from the outside, then the whole thing will -- then that whole rock will get shipped to the Smithsonian at that point, and there, they'll cut it open with a wire saw, if it's, you know, indeed, probably metal, and then make a polished mount and etch it to bring out the texture and so forth. Host: Alright! And then that's what you mean by the facilities, right? They have the -- the proper facilities to do that. So what about here? What kinds of equipment and facilities do we have to make sure that we're handling all of this properly? Dr. Duck Mittlefehldt: So, in the meteorite processing lab, we have [pause] -- we use tools of a very limited set of composition. So, typically, stainless steel hammers and chisels, and -- and the reason is, you know, no matter what we do with a rock from space, we're going to contaminate with something from earth. So the object is to, one, minimize that contamination. So we use materials that we know are not going to, you know, just shed particles everywhere, for example, but also if we -- we use always the tools of the same -- of a given composition so that we know that if we see something like this in the rock, oh yeah, that must have come from the tool. And, you know, I've seen this, rocks are hard to break, and so, you know, your -- your choices are to saw them open or to use a hammer and chisel, and I have seen on a rock that I've gotten, a flake from the chisel that rubbed off. Metal, you know, it's soft, even hardened steel will rub off on occasion. So, you know, I can see this, I can pull that contaminant off or isolate it, in the lab, but, you know, I know then I can do a simple test, yes, that's from the chisel, I don't have to worry about that. I've taken care of it, the rest of the sample is fine. So the object is to minimize contamination or to know what the potential contaminants are. And, you know, there's no way you know of getting -- there's -- with modern technology, we can't, you know, we don't have magnetic levitation devices that we then use a laser to slice them open cleanly. You know, we -- we do with what we got. This isn't Star Trek here yet. Host: [Laughing] We'll just stick with the hammer and chisel for now. So, I mean, when you're cutting these open, and you open them up, what -- what are you looking at? Are you looking at just the rock or are you taking even smaller chunks of that? How is that working? Dr. Duck Mittlefehldt: Well, that all depends on the question that you're trying to answer, and I've done both where I've asked for samples of a, what's called a bulk sample of the rock, so something as representative of the entire rock as possible, and I've looked for individual class in the rock, little fragments that are of a specific type within the rock. All of this is basic 19th century geology, in many respects. You know, in the 19th century, geologists would go out in the field with their hammers, they'd -- they'd beat on a rock and use a hands lens to look at the microscopic, yeah, microscopic texture, mineralogy in it, and, you know, a trained geologist can do the same with a meteorite, and say, yeah, okay, I can see -- I can see what this is, it's a certain type of rock type in there, and that's what I want, I don't want this part over here. So, you know, the traditional geologic methods,but with modern equipment, can be used, and -- and, you know, there's -- there's nothing like the human eye in the brain for sorting out who's who in the zoo. Host: [Laughing] So then how can you -- what -- what are some of the key differences for the -- for the non-geologically-trained eye for whenever you're looking at a rock and you can, you know, you cut it open and you look and you say, that's a meteorite, that's not from earth? Or, this is definitely from earth? Dr. Duck Mittlefehldt: Okay, the -- the first key is -- - is fusion crust. I mentioned this earlier. Host: Oh yeah. Dr. Duck Mittlefehldt: And that -- that's where, going through the atmosphere, friction with the air causes the outer surface to melt, and actually, you know, little bits are flying off all the time, the meteorite we get on the surface is just a small piece of what entered the atmosphere. Most -- sometimes the vast majority of it just ablated away in the atmosphere into little droplets or dust. Host: Wow. Dr. Duck Mittlefehldt: So, you know, if you see a fusion crust on the rock, right away, you know it's -- it's a meteorite, you don't have to go any farther than that. In terms of determining what type it is, more primitive meteorites, these are a type that still have textures and mineralogy that were inherited from condensation and accretion in the solar nebula, that's where individual mineral grains formed out of a gas that -- that was the nebula before the planets were around. And -- and then they glomerate together, these mineral grains, and in the -- in the solar nebula, the dust grains banged, you know, got melted into little, tiny objects which we call chondrules. So, these typical textures are plainly evident to the human eye, even without a microscope. But, you know, with a very low-power microscope you can see them quite easily. Most meteorites, especially primitive ones, contain iron metal, it's actually iron nickel metal. You know, you don't find that on earth except when humans have been involved in -- in smelting iron ore. But so iron metal in a -- in a rock is kind of an indicator that it's quite likely from outer space. Very few occurrences on earth of native metal in a rock. And then, as I said, in the dust in the solar nebula, went through periods of melting and formation of these little, round globules of basically melt globules, which we call chondrules, and -- and from that, we get the name chondrite for these primitive rocks. Well, those stand out in, you know, if you break open a rock, depending on -- on the type, you know, you can see those quite easily, and -- and that's a key. Host: And these have never -- they've been in space for all of time, right? They were formed in space and traveling through space, they've never -- they're not like from another planet or another, like, chipped off another...? Dr. Duck Mittlefehldt: Well, most...no, actually, all meteorites, the only way we get meteorites is for bad things to happen in the asteroid belt. Most meteorites are from asteroids, and when they collide, little fragments get knocked off, and it's -- it's from these fragments that we get meteorites. So they were originally on much larger bodies, I mean, much larger meaning asteroid size, not planet size. Host: Okay. Dr. Duck Mittlefehldt: And they were broken up and then distributed to the earth. You know, one of the, sorry, I'm going to -- I'm going to sort of go back into -- and get into my way back machine and go back to when I was a grad student. Host: Please do! Dr. Duck Mittlefehldt: When I -- you know, when I first started learning about meteorites, one of the mysteries at the time was there was a group of chondrite meteorites called the L chondrites, L was just the name, you know, the -- the name applied to them. That had ages on the order of 500 million years, and this was really odd, because all meteorites are about four and a half billion years old. Well these, they -- they -- these meteorites were originally about four and a half million -- billion years old, but were somehow affected by an event that reset the ages about 500 million years ago. Host: Woah. Dr. Duck Mittlefehldt: And so, you know, this was, you know, just kind of an anomaly. We knew something bad had happened to an asteroid then, about that time, well, fast forward to, I think the 90's, a Swedish geologist started finding in terrestrial sediments fossil meteorites. And, you know, all that's left is a few mineral grains. You -- you can tell, they were found in fine grain limestone, you know, formed on an ocean floor, and all that you could see was this halo of odd stuff, please a few mineral grains that remained from the original meteorite. Well, you know, this guy, and his compadres, studied these mineral grains and they -- they found out they were from the same type of meteorite as these chondrites that were about 500 million years old, and they were in layers in the rock of the earth that were about that age. So, sometime, 500 million years ago, you know, a couple of asteroids collided, and a whole rain of meteorites of this type hit the earth at about, you know, within a few million years when that occurred, and we can find them now. This layer in Sweden that's just chock full of these fossil meteorites. And, you know, to me, that's one of these really neat kind of science stories. Where everything starts tying together. And then to get even further, astronomers looking at what they call asteroid families, so they -- they find an asteroid, they find a whole bunch in orbits similar to it, spectroscopically, they all look to be about the same, and so they -- they figure out, well, these are all, you know, fragments of something that broke apart. Well, they found an asteroid that they figure, you know, based on the spectroscopy, it could be this type of, you know, that formed these L chondrites, and the -- they calculate the age of the family based on dispersion of the fragments, and it's about 500 million years. So, you know, between, you know, meteorite scientists, terrestrial geologists, and astronomers, we -- we've kind of got a neat picture of somehow, you know, about the time of dawn of -- of multicellular life on earth, two asteroids smashed together, and rained down on the earth, and we're still finding fragments coming down to earth now that we can confidently date when this happened in terrestrial laboratories. It's just kind of one of these things that, you know, I find fascinating! Host: [Laughing] I find it -- I mean, a lot of this is over my head, because I don't have the same background as you, but I just find it fascinating that you can look at these rocks and -- and get a story, get a story out of it, you know? Like the story of two asteroids around the time that cellular life was developing coming down to earth and raining down in these locations and telling their story, that's fantastic! Dr. Duck Mittlefehldt: Yeah, and multicellular. So this is when... Host: Multicellular. Dr. Duck Mittlefehldt: This is when, you know, fossils, shortly after the time when fossils started becoming really abundant in the terrestrial record. Host: Wow. Dr. Duck Mittlefehldt: So, yeah, it's just a neat story, and, you know, basically I think that's what got me into geology, originally, was, you know, all you've got is -- is a rock on the surface and somehow you can, you know, if you're smart enough and -- and do the right work, you can start to piece together an entire story of what the earth was like at that time, and so, you know, that's kind of what drew me into geology. Host: That's fantastic. I love it! Especially from -- from my background, marketing and journalistic sort of background, the story telling aspect is just fascinating to me. And that's kind of like, that, you know, the title of this episode is going to be, Infamous Meteorites, and that's kind of like what I really wanted to dive into is, you know, we've talked about where you're finding these meteorites, and then what you're doing with then, you're actually cracking them open and studying them, but then what are you finding? What are you finding inside of these meteorites? What stories? Dr. Duck Mittlefehldt: Yeah. Well, exactly! Host: Yeah, so, you know, one of the ones that I know that was brought to my attention was one of them called Allan Hills, and -- I'm going to -- is it 84001, or do you call it by something else? Dr. Duck Mittlefehldt: No, I call it that. Host: 84001? Okay. Dr. Duck Mittlefehldt: Sometimes it's simply referred to as that rock. Host: [Laughing] Because it's that infamous, huh? Wow! Alright, so what's the story behind -- behind this rock? Dr. Duck Mittlefehldt: Okay, so, this came -- this was found in Antarctica in 1984. And it -- it's [pause] -- it was originally classified as a -- as a type of asteroidal igneous rock that I, at the time, I was studying those -- those types of rocks. You know, my -- my background is heavily-weighted towards an interest in magnetic processes on the earth, the moon, Mars, and asteroids, and -- and so that's why this one was particularly of interest to me. So, I was studying that, along with a bunch of others, that were thought to be basically the same classification of rock, and, unfortunately, Allan Hill's had some puzzling features in it that were -- were a little bit off normal for -- for that rock type. But not so much so that I -- I really stayed up at night worrying about it. Host: [Gary laughing] Dr. Duck Mittlefehldt: And so I wrote a paper on -- on this group of rocks, finally, and sent it in, and one of the reviewers said, well, you know, you point out that there's this anomaly in this rock, and you really ought to try and chase down why it's -- what's going on there, why it's different. And, you know, being a -- a moderately good scientist, I said, okay. I, you know, he has pointed out, it's a problem, I knew it was a problem, but now I've really got to do something about it. So I started working at it, and, honestly, I -- I could not find out what was wrong with this particular rock. It -- it -- there was one mineral phase in it just did not match what anyone would expect for the class. Quite by chance, I got another sample of that rock for another reason. And but it really wasn't the sample I had asked for. So there was as mixup in the thin section. So a thin section is a very thin slice of a rock, it's about 30 microns thick, doubly polished on both sides, and it's used by people who look through microscopes to look at the minerals and textures in a rock, and then you can put that section into an electron microprobe and actually do analyses of the mineral phases in it. Host: Wow. Dr. Duck Mittlefehldt: And so I was -- that's what I was interested in. And this particular rock, which I thought I had, I was interested in the composition of sulfide phases in the rock. So I put the sample in the electron microprobe without actually looking at it in the microscope first, because I had seen this rock before, I knew what it was like, I knew what to expect, I just went straight to the electron microprobe, which actually probably was good because I may have turned the rock in and asked for a different one otherwise. But I'm getting -- I'm looking at it in the microprobe, looking for the mineral phases I'm looking for, and they just really aren't there in the abundance that I expected. Finally I found a grain and I'm -- I'm banging at it with the electron beam, collecting compositions, and the compositions weren't making sense. I was expecting it to be, so I was looking for sulfide phases, so I was expecting to have iron monosulfide, so one iron, one sulfur atom, and the composition that was coming out just was not right. And I checked the calibration, the calibration was perfect, so what's going on? I was looking at the data, not in atoms, but in mass, so weight percent. So when I converted it to atoms, I realized I had two sulfur atoms for every iron atom instead of one, and that's when it hit me what was wrong with this rock. I then backed off, looked at the -- looked at the texture in more detail in the electron microprobe, and realized I had a sample of Allan Hill's, not the meteorite that I thought I had, and I knew which type of rocks had pyrate, the iron disulfide, instead of the iron monosulfide, and I knew those were martian rocks. And so, you know, it was -- it was probably the most satisfying moment I've ever had in my life, excluding when my children were born, and -- and when I got married [Gary laughing], and if my wife listens to this, I hope she hears that, was, you know, suddenly it dawned on me that this was a martian rock that was totally unlike any other martian rock, except the key minerals were in it, and so, you know, it was just one of these aha moments that -- that you live for. And, you know, it was just so much fun. Host: Amazing. Dr. Duck Mittlefehldt: I tell you. Host: So what were those -- the key minerals? What -- what story did they tell? Dr. Duck Mittlefehldt: So the key was because it had the iron disulfide pyrate instead of the iron monosulfide troite, I knew it was martian, and it was a rock type not known amongst the martian meteorites. So what it meant was we had a new type of martian rock that was going to tell us even more about the geologic evolution of Mars then we already knew. And, you know, all of this hit me within like a fraction of a second when I realized what it was. Host: Wow! Dr. Duck Mittlefehldt: So, I mean, I immediately recognized it, it was an, you know, important meteorite. And that it would tell us big things, and, in fact, you know, it has opened up a whole host of, you know, basically this rock ultimately became a founding member of what you might consider astrobiology, and that came when my colleagues here at Johnson Space Center, Dave McKay, Edward Gibson, and Kathie Thomas and now Simon Clemett is at it, and then there were Simon's dissertation advisors, Stanford was on the paper and several other people, you know, they -- they proposed that a certain both mineralogical and compositional and textural objects in this rock were possibly signs of microscopic life that existed on Mars at one point. Host: Wow. Dr. Duck Mittlefehldt: And, you know, to some extent, then this really allowed the whole discipline of astrobiology to blossom because suddenly we had to figure out, you know, what -- how do we understand, how can we possibly search for life and other objects, other planets, you know, what do we need to look for? Because we're used to looking for life on earth, you know, it's -- it's simple. Just walking over here, I, you know, I had to wait while an opossum walked past me in front of, on the walkway. You know, life is everywhere on earth, whereas on Mars, you know, maybe it's not everywhere, and if it was there, how are we going to tell that it was there? What -- what do we need to do? So I would say the import of Allan Hill's not so much that it was hypothesized that life -- fossils of life are in that rock, but that it caused scientists to really take a much more rigorous look at how they will search for life other places of the universe. Host: Wow. And that's -- that's kind of, you know, like you said, the birth, maybe not the birth, but really the blossoming, and that was the word you used of, of astrobiology, life forming outside of earth. That's just a wild concept. How is that even possible? Dr. Duck Mittlefehldt: Yeah, and, you know, the other thing is it did, it was a strong impetus to driving NASA's Mars exploration program, you know, it is -- - a lot of it is geared towards finding evidence for habitability locations on Mars, and, ultimately, you know, from locations where we think there may have been a chance for life, you know, bringing back or -- or studying in situ samples for possible evidence of microbial or -- or larger life on Mars. Host: Yeah, and you said you were, before we started recording, you said you actually were working with Opportunity too, one of the rovers on Mars. Dr. Duck Mittlefehldt: Yeah. I, in 2005, I got attached to the Mars Exploration Rover mission. At the time, we had two rovers going, one Spirit in Gusev Crater, and the other, Opportunity, in Meridiani Planum. Subsequently, Spirit froze to death one winter. Basically, so Spirit lost mobility of one of its wheels, so we were driving backwards, dragging one of the front wheels like a boat anchor through the soil... Host: Oh, man. Dr. Duck Mittlefehldt: And we, you know, the Rover drivers and scientists are very careful. We drove over an area that looked like it was going to be solid, trafficable ground, but it turned out there was a basically a hardpan; layer on top of soil hardpan is kind of an indurated layer that's a little bit stiffer, so it didn't look like it was, you know, loose sand, but it turns out we broke through and got mired in a deep sandpit, basically, and we were unable to extract the rover from the sand, in spite of heroic efforts by the engineers, the Rover drivers at JPL, and the solar panel was tilted at a bad angle for, you know, the oncoming winter sun. So when the sun started getting lower and lower, relative to the tile of the -- of the solar panel, we -- we simply were not getting enough power to keep the rover going and although we tried to contact it again after that winter, we never heard from it again, so it basically just froze to death on Mars. Host: Oh, man, but is Opportunity its twin? Is it the... Dr. Duck Mittlefehldt: Yep, Opportunity is it's twin. Host: And that one's still going, right? Dr. Duck Mittlefehldt: And that one's still going. We're now so -- we're not -- what day is today? Host: The 8th. Yeah, we're now about two weeks away from the anniversary, the 16the anniversary of landing on Mars for Opportunity. Host: 14 years? Wow! Dr. Duck Mittlefehldt: It's still going strong, and we are still actively exploring the geology of Meridiani Planum. We don't have all the instruments we had when we landed, but we're still making great scientific discoveries, even with the limited rover ability. Host: How about that? So how is -- how was, you know, working with a rover on Mars different from looking at meteorites? Maybe even martian meteorites, like the Allan Hills, here on earth? How is that different? Well, so, you know, here on earth, I have the luxury of taking a sample into the lab and -- and using state-of-the-art scientific equipment to -- to tease out, tease out its story. On Mars, we have cameras that we can use to image the terrain. So right away, textures, and we have a microscopic camera, so textures allow us to, you know, make inferences about what the rock -- how the rock might have been formed. We have a camera with 13 color filters on it, so we can do some limited spectroscopy of the rock that helps us compare a limited set of mineralogical variations in the rocks, and then we have the alpha particle x-ray spectrometer, which allows us to do bulk compositions of surfaces. So, between them, we -- we can -- we can get a fairly good handle of the mineral -- well, mostly the textures and bulk composition, and, to some extent, neurology of a rock, and that helps us understand what processes might have formed the rock altogether. And, you know, to some extent, where Opportunity is a high-tech version of a 19th century terrestrial geologist. [Gary laughing] But, you know, the, obviously the spectrometer is better than what they had in the 19th century, and the chemical composition is as -- as good as we could do then and actually better for many elements, but we're still not at the cutting edge, as you -- as you could do if you had a, you know, a mobile laboratory up on Mars. Host: Yeah, definitely. And that's kind of your -- your trade-off, right? Is like, here, you know, you can bring into a lab with all the latest equipment and -- and study these meteorites, but, like you said before, like there's a certain amount of contamination that's going on with just the fact that a meteorite has come through the atmosphere and hit the -- hit the -- surface of the earth, you know, you have to deal with that, but then you have limited instruments right there on -- on Mars. So, I guess you just kind of have these tradeoffs [laughing]. Dr. Duck Mittlefehldt: Yep. Host: So another one that you mentioned, another infamous meteorite, was one called Orgueil, and that's one -- that one's much earlier than the Allan Hills one, right? Dr. Duck Mittlefehldt: So Orgueil fell in France in 1864, if I -- if I remember right, and what's key here is it's a -- it's a very primitive type of meteorite. It's a carbonaceous chondrite. The -- the two letter name for it is a CI carbonate -- chondrite. These are amongst the most primitive materials, primitive meteorites that we have for study. They're bulk compositions, basically are identical to what we see for the photosphere of the sun, excluding the most volatile elements like -- like helium, hydrogen, and oxygen and so forth, but if you could take the sun, you know, a cubic kilometer of the sun and condense out all the condensable matter, it would -- the composition would be very much like a carbonaceous, CI carbonaceous chondrite. So, these have always been the touchstone for understanding the chemical evolution of the solar system. They are our -- our basis for seeing who has varied from the original composition. But they're highly-altered, so they are almost completely made up of clays and other low-temperature alteration phases. So the original high-temperature phases have been replaced. So, at some point, these things were altered by water in their parent asteroid to the point where all that's left is -- is basically clay. This makes them [sigh] -- this made Orgueil susceptible to nefarious individual, tempting to prove something, what don't know, because we don't know who that individual was, but, you know, I would call Orgueil the Piltdown Man of meteorites. So Piltdown Man was -- was this fake fossil made in about 1912 I think to look like it had some of the attributes of an ape, but some of the attributes of a modern human, because someone that that's the way human evolution went, and they wanted to show that we had fossils that fit in within that theory. Well, Orgueil, at some point, was broken open, and it turns out, because this is clay, you can -- if you get it good and wet, you can kind of break it open like clay, and then they had stuffed in terrestrial seeds and plant fragments and coal, and then put it back together, and coated the outside with glue to make it look like it still had the fusion crust on it. Host: Oh my gosh! Dr. Duck Mittlefehldt: And then this sample was sealed in a bell jar in a museum from 1864, so apparently it happened very early, we don't know who did it, or why, you know, what were they trying to accomplish by this? Because it was going to be sealed in a bell jar, you know, did they think someone was going to then take it out and look at it, I don't know, but this -- this came to light in 1960's then. Host: Oh! Dr. Duck Mittlefehldt: And so, a well-known meteoriticist, by the name of Ed Anders, very famous, very smart man, he led a study that was published 100 years later, in 1964 in science, where he uncovered, you know, all of this forensic meteoritic work where he showed that, you know, the seeds were, you know, terrestrial seeds, the coal fragments were in there, that glue had been used to put it back together and make it look like it was whole, and -- and all of this, and -- and so that's why, you know, this is an infamous -- infamous meteorite for those who are in the know. Most people won't have heard of it, but, you know, like I said, it's kind of the Piltdown Man of meteoritics. Host: Wow! Dr. Duck Mittlefehldt: So someone had an agenda, they wanted -- they, for some reason, they wanted to show that life could form on an asteroid or -- or in space, or something, I don't know, but, obviously, they had -- they had some agenda when they did this. Host: Yeah, I know, but seeds and glue are not really a good way to convince people [laughter]. Dr. Duck Mittlefehldt: No. You know, back in the, you know, mid-19th century, you know, had it been opened up and studied then, maybe it would have caused quite a furor, but, as far as I know, this was only discovered in, you know, a century later. Host: Wow! A hundred years of people thinking this is some kind of like capsule of extraterrestrial life, how about that? So, you know, all of these kind of tell a story and, unfortunately, some of them, this [laughing] -- this particular one is a little bit of a lie, but, you know, we are cracking these open to search for evidence of -- of whatever we can find, right? Maybe -- maybe the formation of a planet, maybe the formation of solar system, maybe the formation of life. So, you know, what, in a perfect world, I guess, what would you like to do -- what would you like to study? What would you like to see and do to really maximize what you can find about learning more about our solar system and about life in the universe Dr. Duck Mittlefehldt: Well, I mean, that -- that's kind of a difficult question for a scientist to answer, because, you know, truth be told, we're all paid to pursue our hobbies, and so we all have our own hobby horses. So, as I -- as I mentioned, you know, my particular interests are in igneous processes, I, you know, on the earth, moon, Mars, asteroids, I -- I like magmatic rocks, and, you know, I couldn't tell you why, it's just the way I am [Gary laughing]. So, one of the things -- one of the things that's very curious about asteroidal igneous rocks is that asteroids were melted very early in the solar system, probably within a couple million years of the formation of the earliest-known solids in the solar system. So something had to heat up relatively small objects, maybe a few hundred kilometers, you know, 200 miles in -- or in radius, something like that, to the point where they were melted and then cooled down and then they completely shut off after that. So, it was a very, very intense heat source that acted early, died out, and then never came back. You know, we think we know what -- what caused this, but there, you know, and so the -- the leading contender is radioactive heating by a very short-lived isotope of aluminum. It has a half-life of about 730 million years, and so, and aluminum is a -- is a major element in rocks, so, if you -- if you accumulate an asteroid early enough, when there's this aluminum-27 still alive, you've, you know, -- you've then encapsulated a very potent heat source inside that rock. And so that's what we think happened, but, still, you know, we can admit, as scientists, we can imagine this process going on, but geology is always much more complicated than our imaginations. So there are things that I don't understand, things that, as far as I know, no one really understands about how asteroids went from being primitive objects that accumulated from minerals formed in the solar nebula to basically a molten ball that then crystallized out igneous magmatic rocks, similar to what we see on earth. I would desperately like to get, you know, be able to find out more about how -- what was going on, you know, what have we missed, because we, you know, we tend to think of things in -- in the simplest terms, you know, it was heated up, melted, crystallized, that's it, well, we know that -- that's not all the story. Host: Yeah. Dr. Duck Mittlefehldt: And I think all meteoriticists have, in the back of their minds, for their particular hobby horses, just things they don't quite understand. They know the -- the broader picture, but what are the finer details that went into -- to this. We -- we know we've got the basic story, but what are, you know, all the chapter and verse that go into this basic story? Host: Wow. Dr. Duck Mittlefehldt: So, you know, that's what drives me, and it's all -- it's all a matter of, you know, learning something new that -- that, you know, pushes forth human knowledge. You know, what I do is -- is nowhere near applied science. It's pure basic science. So I can't -- I can't talk to someone and say, you know, tomorrow, you're going to be able to have a better life because of what I do, only if, you know, unless you think a better life means knowing more [Gary laughing]. But you never know, because, in -- in general, a large fraction of basic research ultimately does find an application. Right now, I don't know what that application might be, but I won't say there's never going to be some application for what I do, but, for me, it's -- it's this sense of learning something that -- that drives me. Host: Yeah. Why learn if you don't think it's going to end up, you know, giving you a better life. I mean, honestly, like, you know, learning things kind of helps you understand things, helps things come together, to me, that makes me pretty happy. So I could see that, you know, better understanding, giving me a better life. Dr. Duck Mittlefehldt: Yeah, well, I mean, you know, humans have always been curious, and, you know, I suspect the reason we're curious is because it's beneficial for survival, because, you know, when -- when you're out on the savannah hunting lions, or hunting gazelles, if you see something moving the weeds over there, you know, okay, is that a gazelle or is that a lion about to eat me instead? So, you know, humans are geared to being curious about their environment, because it's a survival mechanism. Host: Yeah. Dr. Duck Mittlefehldt: And, for scientists, we have now transposed that, you know, away from worrying about whether we're going to be eaten to just, you know, a broad knowledge in general. Host: [Laughing] Well, I think last time we sat down with Dr. Burton, he said, he kept talking about this time machine, how easy it would be -- how nice it would be to just kind of hop in a time machine, watch these processes take place, and be like, ah [snapping fingers], that's how -- that's how it takes place. I mean, and then there's whole philosophical idea of, well, is that going to alter the universe if you go back in time and watch these things? So, you know, that was another tangient we could have gone on and we didn't, but [laughter], but it would be nice to, you know, for the, you know, to improve our knowledge a little bit of how all this stuff works and comes together. Alright, so, Duck, I think -- I think that about wraps it up for today. So, thank you so much for coming on the podcast and kind of... Dr. Duck Mittlefehldt: It's been a pleasure. I hope I've imparted something that makes sense to the listeners and -- and that they will find interesting. Host: It's actually you know, you know, we're talking about rocks, if you think about it, but it's absolutely fascinating, what you can found and the stories behind these rocks and what they tell you about the universe, and even just your trips to Antarctica are pretty fascinating as well, so, again, thanks so much for coming on and telling the stories of these beautiful rocks and your trips to Antarctica, and, yeah, hopefully we'll -- we'll find some cool evidence of life or, you know, you'll find that key ingredient as to why, you know, the asteroids did what they did. Dr. Duck Mittlefehldt: Yeah, well, I hope so, and thank you very much for the invite! Host: Absolutely. [ Music & Radio Transmissions ] Hey, thanks for sticking around. So, today, we talked with Dr. Duck Mittlefehldt about some of the cooler, infamous meteorites that have been discovered throughout the years, and then some interesting stories about Antarctica and how he's finding them, it's really a cool process, and he works with the ANSMET, it's the Antarctic Search for Meteorites. So if you want to learn more about ANSMET and some of the adventures that are going on in Antarctica, and some of the curious findings in these meteorites, especially some that may or may not be life, it turns out there was some, you know, fake meteorites at the end of there, which is kind of disappointing, but that's okay. You can go to ares.jsc.nasa.gov to get the full scoop on all of these cool meteorites, and -- and you can learn how to get your hands on one of these meteorite samples to study them. If you go to social media on the NASA Johnson Space Center accounts, or if you go to ARES, or astromaterials, NASA astromaterials, we got pages on Facebook, Twitter, and Instagram where we like to share these stories, just use the hashtag, ask NASA, on -- on your favorite platform to submit an idea, or if you have a question about meteorites, or if you want to submit a new topic for the show, to make sure to mention it's for, Houston, We Have A Podcast. So this podcast was recorded on January 8th, 2018. Thanks to Alex Perryman, Greg Wiseman, Tracy Calhoun, and Jenny Knots, and thanks again to Dr. Duck Mittlefehldt for coming on the show! We'll be back next week!