Should we maintain baby hatches in our society?

Directory of Open Access Journals (Sweden)

Asai Atsushi

2013-02-01

Full Text Available Abstract Background A baby hatch called the “Stork’s Cradle” has been in place at Jikei Hospital in Kumamoto City, Japan, since May 10, 2007. Babyklappes were first established in Germany in 2000, and there are currently more than 90 locations. Attitudes regarding baby hatches are divided in Japan and neither opinions for nor against baby hatches have thus far been overwhelming. To consider the appropriateness of baby hatches, we present and examine the validity of each major objection to establishing baby hatches. Discussion There are various objections to baby hatches as follows: It violates a child’s right to know the identity of his or her biological parents by allowing anonymous birth; it neglects fulfillment of the biological parents’ basic obligation to raise their child and its very availability induces abandonment of infants; some people abuse it for very selfish reasons; it cannot save babies’ lives; the rights of one parent can be ignored if the other surrenders a child without his or her consent; it puts a baby in medical jeopardy; and it has no clear legal basis. The authors would argue that there are many plausible refutations for each objection mainly based on priority of child’s right to life, pregnant women’s vulnerability and necessity of anonymity, social responsibility to protect and raise children, differences between dropping a child off at a baby hatch and child neglect, limited function of social childcare center, inevitability of abuse by a minority of people, necessary distinction between outcomes that occur only because baby hatches exist and those that occur regardless of their existence, important local direct and upmost measures for women in trouble, and difference between ambiguous legality and illegality. Summary We argue that a certain number of baby hatches should continue to be established as a last resort, in a form that can maintain anonymity if the parent dropping the child off so desires. It

Diapause in Calanoid Copepods: within-clutch hatching patterns

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Bart T. DE STASIO

2004-09-01

Full Text Available Diapause is a major life history feature of many invertebrate organisms. Determining the phenology of diapause is critical for understanding survival and reproductive success of individuals as well as the long-term viability of many populations. The time spent in dormancy by individuals and variability among offspring in the duration of dormancy are two important aspects of invertebrate life histories. Some data are available, especially on duration of diapause, for plants and insects, but little information is available concerning variability among offspring in diapause traits. This is especially true for crustacean zooplankton, where essentially no information has been published on duration of diapause or variability among offspring in diapause timing or dynamics. Here I present data on the duration of diapause, and variability among offspring for diapause characteristics. The freshwater calanoid copepod Onychodiaptomus sanguineus, an obligately sexual species, was collected from Bullhead Pond, Rhode Island, U.S.A., and raised under conditions in the laboratory to induce production of diapausing eggs. One hundred clutches of these diapausing eggs (920 total eggs were incubated for over two years in a full-factorial experiment testing the effects of temperature and photoperiod cycles on the hatching dynamics and duration of diapause. Overall hatching success was highest (approximately 86% for eggs exposed to simultaneous temperature and photoperiod cycles mimicking natural changes, and was lowest (approximately 20% when eggs were incubated at constant temperature (4 °C and in constant dark conditions. The highest fraction of eggs hatched at approximately 550 days of age, but the age of eggs at hatching was highly variable among clutches. There was also large variability within clutches for hatching patterns, with some clutches containing eggs that all hatched synchronously and others in which eggs hatched more continuously throughout the

Adaptive hatching hypotheses do not explain asynchronous ...

African Journals Online (AJOL)

At the core of the suite of adaptive hatching hypotheses advanced to explain asynchronous hatching in birds is the assumption that if food is not limited then all the hatchlings will develop normally to adulthood. In this study Brown-headed Parrot Poicephalus cryptoxanthus chicks were hand fed and weighed on a daily basis.

Broiler adaptation to post-hatching period

Directory of Open Access Journals (Sweden)

Maiorka Alex

2006-01-01

Full Text Available In the latest years more attention has been given to mechanisms for bird adaptation at post-hatching period by management of environmental conditions and formulations of diets offered during this period when digestive, immune, and thermo-regulating systems suffer slight changes. In post-hatching period, digestive system is anatomically complete, but its functionality is still immature in relation to adult birds. The chick immunity depends on maternal antibodies transferred to egg just before laying. In addition, variations within thermal comfort zone might affect initial development of chick. For example, high temperatures may induce hyperthermia with dehydration, while low temperatures may lead to hypothermia responsible by pulmonary hypertension syndrome. In conclusion, productivity might be enhanced when good conditions are offered to chicks during the period from last embryo development to first days after hatching.

Temperature effects on copepod egg hatching: does acclimatization matter?

DEFF Research Database (Denmark)

Hansen, Benni Winding; Drillet, Guillaume; Kozmér, A.

2010-01-01

This report investigates female sizes, egg sizes and egg hatching rates in relation to temperature for the near-shore calanoid copepod Acartia tonsa cultured at 6, 9, 14 and 24°C for several generations to achieve acclimatization. Inverse size relationships of eggs and females were revealed...... with increasing temperature. Eggs produced at 6°C were 85 ± 4 µm in diameter, but decreased to 80 ± 3 µm at 24°C. Female cephalothorax length was 840 ± 52 and 692 ± 39 µm at 9 and 24°C, respectively. Parallel hatching experiments were performed between non-acclimatized and acclimatized cultures across a range...... of temperatures reflecting natural conditions in Danish waters. A greater fraction of eggs enter quiescence as temperature declines. Eggs were able to hatch at temperatures as low as 1.5°C. Final egg hatching success increased with temperature. Acclimatization of the copepods resulted in a lower maximum hatching...

The hatching larva of the priapulid worm Halicryptus spinulosus

OpenAIRE

Janssen, Ralf; Wennberg, Sofia A; Budd, Graham E

2009-01-01

Abstract Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid developmen...

Delayed egg hatching of Anopheles gambiae (Diptera: Culicidae) pending water agitation.

Science.gov (United States)

Ebrahimi, Babak; Shakibi, Sanam; Foster, Woodbridge A

2014-05-01

Mosquito eggs laid on water surfaces typically hatch spontaneously soon after the embryos within them become fully formed first-instar larvae. However, we have found that Anopheles gambiae Giles, an important vector of malaria in Africa, exhibits delayed hatching until the water surface is agitated, a feature overlooked in most laboratory colonies. Agitation within 24 h postoviposition, before embryonation was complete, failed to stimulate delayed postembryonic hatching of isolated eggs on the following day (day 2), when < 1% had hatched spontaneously. However, 5 min of water agitation of these dormant pharate first-instar larvae on day 2 resulted in an almost immediate hatch of 63.3 versus 0% of nonagitated controls, plus another 3.9 versus 0.3%, respectively, during the following 24 h. With daily agitation, installment hatching occurred mainly during 2-6 d postoviposition. The mean cumulative hatch after 7 d of daily agitation was 83.1 versus 1.1% of nonagitated eggs. Experiments with eggs in groups demonstrated that egg density and activity of already-hatched larvae had no stimulatory effect. Eggs stored 1-4 wk at 25.5 or at 15.5 degrees C, and then agitated daily for 6 d at 25.5 degrees C, showed a gradual decline in viability. Viability was sustained longer at the lower temperature. Implications of agitation-induced egg hatching for rainy-season and dry-season ecology of An. gambiae are discussed. Suspended hatching and cool storage already are proving convenient for efficient mass rearing and accurate modeling of weather-based population dynamics.

Copepod recruitment and food composition : Do diatoms affect hatching success?

DEFF Research Database (Denmark)

Jonasdottir, Sigrun; Kiørboe, Thomas

1996-01-01

was fed several different diets while egg production and hatching success were monitored. The diet was analysed for fatty acid content as an indicator of food quality. Both egg production and hatching were found to be affected by the nutritional quality of the food. Hatching was also highly dependent......Laboratory experiments were conducted to differentiate between factors controlling the hatching success of copepod eggs. Factors that could affect viability of eggs; viz food quality, female condition and external factors were investigated. In a series of experiments the copepod Acartia tonsa Dana...

How to hatch from the Common Cuckoo (Cuculus canorus) egg: implications of strong eggshells for the hatching muscle (musculus complexus)

Czech Academy of Sciences Publication Activity Database

Honza, Marcel; Feikusová, Kateřina; Procházka, Petr; Picman, J.

2015-01-01

Roč. 156, č. 3 (2015), s. 679-685 ISSN 0021-8375 R&D Projects: GA ČR(CZ) GAP506/12/2404; GA AV ČR IAA6093203 Institutional support: RVO:68081766 Keywords : Brood parasitism * Common Cuckoo * Coevolution * Adaptations * Hatching muscle * Hatching Subject RIV: EG - Zoology Impact factor: 1.419, year: 2015

Preliminary examination of hatching season and growth of ...

African Journals Online (AJOL)

The hatching period and the growth of Malawian cyprinid Engraulicypris sardella larvae and juveniles collected from two sites along the southwestern shoreline of Lake Malawi were investigated using otolith increment information. The lapillus was used to determine the age in days following previous studies. The hatching ...

Effect of Egg Orientation on Malposition in Hatching Eggs

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İsmail Durmuş

2015-09-01

Full Text Available This research was conducted to determine the effects of orientation in the hatching eggs on hatching results and position disorders, so the eggs were placed in incubator for 3 groups as orientation of normal, horizontal and small end up. In this study, 1680 hatching eggs were divided into 3 groups with 7 replicates of 80 eggs in each. Hatchability of fertile eggs, malformation ratio, malposition ratio, weight loss ratio, chick quality, embryo death ratios in the early, middle and late stage of embriogenesis and mortality ratio were investigated in this research. There were significant differences among the groups in terms of egg weight loss ratio, embryo death in the late stage of embriogenesis, malposition ratio, hatching rate , whereas no significant differences among the groups in respect to malformation ratio, chick quality, embryo death in early and late embriogenesis. It was determined that the late embrionic mortality increased because of the position errors in case of hatching eggs orientation and the head of the embryo in small end up of eggs.

Hatch ability, growth and some blood biochemical parameters in hatching quails following the exposure of incubated eggs to red laser

International Nuclear Information System (INIS)

Abu Taleb, A.M.

2003-01-01

A total number of 600 Japanese quail eggs were used this study. The eggs were divided into three groups then incubated. Eggs of groups one (G1) and two (G2) were exposed to 30 and 60 minutes, respectively, to the red laser rays (Laser Pointer LD-300) at 0, 7 and 14 days of embryogenesis,while group three (G3) was not treated and served as control. Hatch ability body weight and mortality were recorded weekly for each group. Furthermore, five blood samples were collected from one day old chicks at hatching and at six weeks of age from each group to determine some hematological parameters including RBCs, WBCs, PCV and Hb. Liver enzyme activities (GPT and GOT), kidney function (uric acid and creatinine), cholesterol and total lipids were determined for the 6 weeks old chicks only. The present results indicated that exposure to red to significant increase in hatch ability percentage and promoted early hatch ability and decreased embryonic mortality in treated groups (G1) and (G2) than control (G3). Significant decreases in RBCs counts, cholesterol and total lipids were found in G1 and G2. Exposure of developing embryos to red laser radiation had no significant effect on PCV in one day old hatching chicks, or RBCs and WBCs counts, PCV, GOT, uric acid creatinine in six weeks old birds. At the same time, significant increases in Hb and WBCs counts were occurred in one day old chicks and Hb and GPT in six weeks old birds. It could be concluded from the reported findings that exposure to red laser radiation may affect some factors that accelerate hatch ability and cause changes in some biochemical parameters in Japanese quails

Bleach Solution Requirement for Hatching of Daphnia magna Resting Eggs

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Catur Retnaningdyah

2016-11-01

Full Text Available Daphnia (water fleas belong to the zooplankton group called Cladocerans have sexual reproduction when conditions less favorable that produce diapausing eggs are enclosed in the ephippium. Hatching ephippial eggs in the laboratory is important in ecological, toxicology, genetical, and evolutionary studies. This study aims to improve the current methods of egg hatching from ephippium. Each of 50 ephippium were treated together by placing them in a glass jar and adding 50 mL bleach solution (sodium hypochlorite. Concentrations of sodium hypochlorite used in this experiment were 0%, 0.5%, 1%, 2%, 4% and 8%. These concentration treatments were crossed with the following exposure times (1, 2, 4, 8, 16, and 32 minutes. Culturing was done in 80 mL of artificial Daphnia medium, incubated in constant light and temperatures 20°C for 25 days. There were two repetitions in this experiment that were run at the same time. Result of this experiment showed that pretreatment with 0.5-8% bleach solution significantly increases the yield of total hatch rate of Daphnia magna resting eggs by about 21% over unbleached control. However, there was no significant difference among the bleach treatments. Concentration of bleach solution 0.5%, 1% and 4% significantly accelerated the time period until the first hatching (first day hatching. Difference of exposure time (1 - 32 minutes at each concentration treatments were not influence the yield of total hatch and the time period until first hatching.

The hatching larva of the priapulid worm Halicryptus spinulosus.

Science.gov (United States)

Janssen, Ralf; Wennberg, Sofia A; Budd, Graham E

2009-05-26

Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid development. These findings may further help unravelling the phylogenetic position of the Priapulida within the Scalidophora and hence contribute to the elucidation of the nature of the ecdysozoan ancestor.

ZZ HATCHES-18, Database for radiochemical modelling

International Nuclear Information System (INIS)

Heath, T.G.

2008-01-01

1 - Description of program or function: HATCHES is a referenced, quality assured, thermodynamic database, developed by Serco Assurance for Nirex. Although originally compiled for use in radiochemical modelling work, HATCHES also includes data suitable for many other applications e.g. toxic waste disposal, effluent treatment and chemical processing. It is used in conjunction with chemical and geochemical computer programs, to simulate a wide variety of reactions in aqueous environments. The database includes thermodynamic data (the log formation constant and the enthalpy of formation for the chemical species) for the actinides, fission products and decay products. The datasets for Ni, Tc, U, Np, Pu and Am are based on the NEA reviews of the chemical thermodynamics of these elements. The data sets for these elements with oxalate, citrate and EDTA are based on the NEA-selected values. For iso-saccharinic acid, additional data (non-selected values) have been included from the NEA review as well as data derived from other sources. HATCHES also includes data for many toxic metals and for elements commonly found in groundwaters or geological materials. HARPHRQ operates by reference to the PHREEQE master species list. Thus the thermodynamic information supplied is: a) the log equilibrium constant for the formation reaction of the requested species from the PHREEQE master species for the corresponding elements; b) the enthalpy of reaction for the formation reaction of the requested species from the PHREEQE master species for the corresponding elements. This version of HATCHES has been updated since the previous release to provide consistency with the selected data from two recent publications in the OECD Nuclear Energy Agency series on chemical thermodynamics: Chemical Thermodynamics Series Volume 7 (2005): Chemical Thermodynamics of Selenium by Aeke Olin (Chairman), Bengt Nolaeng, Lars-Olof Oehman, Evgeniy Osadchii and Erik Rosen and Chemical Thermodynamics Series Volume 8

The hatching larva of the priapulid worm Halicryptus spinulosus

Directory of Open Access Journals (Sweden)

Budd Graham E

2009-05-01

Full Text Available Abstract Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid development. These findings may further help unravelling the phylogenetic position of the Priapulida within the Scalidophora and hence contribute to the elucidation of the nature of the ecdysozoan ancestor.

Cell and genetic predictors of human blastocyst hatching success in assisted reproduction.

Science.gov (United States)

Syrkasheva, Anastasiya G; Dolgushina, Nataliya V; Romanov, Andrey Yu; Burmenskaya, Olga V; Makarova, Nataliya P; Ibragimova, Espet O; Kalinina, Elena A; Sukhikh, Gennady T

2017-10-01

The aim was to identify cell and genetic predictors of human blastocyst hatching success in assisted reproduction programmes via a prospective case-control study. Blastocysts, donated by couples in assisted reproduction programmes were used. Hatching success assessment was performed after 144-146 h post-fertilization. The mRNA expression levels of cathepsin V (CTSV), GATA-binding protein 3 (GATA3) and human chorionic gonadotropin beta subunit 3, 5, 7 and 8 (CGB) genes were detected by quantitative real-time polymerase chain reaction. The odds ratio (OR) of hatching due to zona pellucida (ZP) thickness, oocyte and sperm quality, embryo quality and mRNA expression of CTSV, GATA3 and CGB genes in blastocysts was determined. From 62 blastocysts included in the study, 47 (75.8%) were unable to hatch spontaneously. The ZP thickening, and oocyte and sperm quality did not affect human blastocyst ability to hatch, except the combination of cytoplasmic and extracytoplasmic oocyte dysmorphisms (OR = 1.25; 95% confidence interval = 1.08, 1.45). Hatching-capable blastocysts had higher Gardner scale grade and mRNA expression of CTSV, GATA3 and CGB genes than hatching-incapable blastocysts. The human blastocyst hatching success depends on the blastocyst Gardner grade, but not on ZP and gamete quality. Blastocyst development was regulated by CTSV, GATA3 and CGB gene expression.

29 CFR 780.211 - Contract production of hatching eggs.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Contract production of hatching eggs. 780.211 Section 780... eggs. It is common practice for hatcherymen to enter into arrangements with farmer poultry raisers for the production of hatching eggs which the hatchery agrees to buy. Ordinarily, the farmer furnishes the...

Suspension of Egg Hatching Caused by High Humidity and Submergence in Spider Mites.

Science.gov (United States)

Ubara, Masashi; Osakabe, Masahiro

2015-08-01

We tested the effects of high humidity and submergence on egg hatching of spider mites. In both the high humidity and submergence treatments, many Tetranychus and Panonychus eggs did not hatch until after the hatching peak of the lower humidity or unsubmerged controls. However, after humidity decreased or water was drained, many eggs hatched within 1-3 h. This was observed regardless of when high humidity or submergence treatments were implemented: either immediately after oviposition or immediately before hatching was due. Normal eyespot formation was observed in most eggs in the high humidity and submergence treatments, which indicates that spider mite embryos develop even when eggs are underwater. Therefore, delays in hatching are not caused by delayed embryonic development. A delay in hatching was always observed in Panonychus citri (McGregor) but was more variable in Tetranychus urticae Koch and Tetranychus kanzawai Kishida. The high humidity and submergence treatments affected but did not suppress larval development in these species. In contrast, many Oligonychus eggs died following the high humidity treatments. In Tetranychus and Panonychus spider mites, suspension of egg hatching may mitigate the adverse effects of rainfall. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

1,10-Phenanthroline and its derivatives are novel hatching stimulants for soybean cyst nematodes.

Science.gov (United States)

Nonaka, Shiori; Katsuyama, Tsutomu; Kondo, Tatsuhiko; Sasaki, Yasuyuki; Asami, Tadao; Yajima, Shunsuke; Ito, Shinsaku

2016-11-01

Soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is a plant-parasitic nematode and one of the most serious soybean pests. Herein, we present the heterocyclic compound 1,10-phenanthroline (Phen) and its derivatives as novel hatching stimulants for SCN. Phen treatment promoted hatching of second-stage juveniles of SCNs in a concentration-dependent manner. In addition, the hatching of SCNs following treatment with Phen occurred more rapidly than that following treatment with the known hatching stimulant, glycinoeclepin A (GEA). Furthermore, the co-application of Phen and GEA enhanced SCN hatching rate compared with that of Phen or GEA alone. A structure-activity relationship study for Phen derivatives suggested that 2,2'-bipyridine is the essential structure of the SCN-hatching stimulants. These results suggest that Phen and its derivatives activate different hatching pathways of SCNs from GEA. Copyright © 2016 Elsevier Ltd. All rights reserved.

The influence of encapsulated embryos on the timing of hatching in the brooding gastropod Crepipatella dilatata

Science.gov (United States)

Andrade-Villagrán, P. V.; Baria, K. S.; Montory, J. A.; Pechenik, J. A.; Chaparro, O. R.

2018-01-01

Encapsulated embryos are generally thought to play an active role in escaping from egg capsules or egg masses. However, for species that brood their egg capsules, the factors controlling the timing of hatching are largely unclear, particularly the degree to which hatching is controlled by the embryos rather than by the mother, and the degree to which the hatching of one egg capsule influences the hatching of sister egg capsules within the same egg mass. We studied aspects of hatching using the direct-developing gastropod Crepipatella dilatata, which includes nurse eggs in its egg capsules and broods clusters of egg capsules for at least several weeks before metamorphosed juveniles are released. Isolated egg capsules were able to hatch successfully, in the absence of the mother. Moreover, the hatching of one capsule did not cause adjacent sister capsules to hatch. Hatched and un-hatched sister egg capsules from the same egg mass differed significantly in the number of metamorphosed juveniles, average shell size, offspring biomass (juveniles + veliger larvae), and the number of nurse eggs remaining per egg capsule. Differences in when egg capsules hatched within a single egg mass were not explained by differences in egg capsule age. Hatching occurred only after most nurse eggs had been ingested, most offspring had metamorphosed into juveniles, and juveniles had reached a mean shell length > 1.36 mm. Whether the mother has any role to play in coordinating the hatching process or juvenile release remains to be determined.

A Big Bang or small bangs? Effects of biotic environment on hatching

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Marina MANCA

2008-08-01

Full Text Available The beginning and end of diapause are two important transition points in cladoceran life history. The influence of environmental variables on the dynamics of these processes still deserves attention, especially as concerns the role of biotic factors. In this paper we focus on emergence from diapause, testing (1 whether ephippia of Daphnia obtusa Kurz can assess the presence in the water of typical planktivorous fish or ostracods, and (2 whether such an assessment results in changes in hatching strategy. Total number of hatchlings from D. obtusa ephippial eggs did not differ between the control and the treatments in which the presence of fish or ostracods could be detected (ANOVA, P = 0.884. However, hatching dynamics were different: most of the eggs hatched synchronously at day 4 (83.3% of the total hatchlings number in the control, while only a low proportion of eggs hatched on day 4 in the fish (38.3%, and ostracod treatments (24.0% of the total. Mean hatching time was longer, and variability larger, in the treatments than in the control; differences resulted statistically significant (ANOVA, P = 0.005. With respect to the control, representing a simple microcosm controlled by abiotic variables only, the treatments may be regarded as relatively complex environments, in which Daphnia is also exposed to biotic cues. Under these more complex conditions, the same number of hatchlings is obtained through different hatching dynamics. In the treatments, the first hatchlings appeared later and the hatching rate was more variable than in the control. These observations confirm previously observed patterns from laboratory experiments which tested the effect of competition and fluctuating environmental conditions (light:dark, temperature regimes on D. obtusa reproductive and demographic parameters. They are also in agreement with recently obtained evidence concerning the importance of biotic cues for hatching of ephippial eggs. Overall, the evidence

UJI PERBEDAAN SALINITAS TERHADAP DAYA TETAS TELUR (Hatching Rate KEPITING BAKAU (Scylla serrata

Directory of Open Access Journals (Sweden)

Budi Mulyawan

2010-10-01

Full Text Available Mud crabs (Scylla sp. is one of marine commodities that is profitable. Mangrove crabs are able to hatch and breed within large variety of salinity. One of the main factors affecting hatching rate and also breeding is salinity. This research is aimed to know the effect of salinity to hatching rate of mud crabs. The design used was complete random sampling through three treatments: those are 15%o, 25%o and 30%o with 3 repetitions. Result of this research shows that hatching rate of mud crabs is affected by salinity. Treatment B (25 %o is significantly different with treatment A (15%o and C (30%o. The most appropriate hatching condition is gained from treatment B with average value 91.8%.Keywords: mud crab, Scylla sp, mangroves

[Immunocytochemical studies on the phase of differentiation of hatching gland cells in brine shrimp, Artemia salina].

Science.gov (United States)

Li, Ling; Fan, Ting Jun; Wang, Xiao Feng; Cong, Ri Shan; Yu, Qiu Tao; Zhong, Qi Wang

2004-04-01

Hatching enzyme (HE), synthesized in hatching gland cells (HGCs), plays vital roles in animal hatching. Immunocytochemical techniques employing anti-GST-UVS.2 antiserum, prepared from Xenopus HE and with specificity to brine shrimp HE, were first used to investigate the differentiation and variability of hatching gland cells (HGCs) in the hatching process of embryos of brine shrimp, Artemia salina, in this study. HGCs with immunoreactivity to anti-GST-UVS.2 antiserum were identified, for the first time, in brine shrimp embryos during hatching process. Immunocytochemical staining results showed that, (1) HE-positive immunoreactivity is really specific to Artemia HE, and its appearance and disappearance are closely correlated with the hatching process of Artemia salina. (2) Artemia HGCs, first appeared in embryos 5 hours before hatching and disappeared 4 hours after hatching, were also a transient type of cells, with an existence period of 9 hours. (3) The head portion of Artemia embryo is probably the initial position of HE secretion, and likely to be the main position of HE secretion as well. The detailed process and mechanism need to be studied. (4) The appearance of HGCs is in a synchronous mode from places all over the embryos, and their disappearance is also in a synchronous mode. (5) The number of HGCs increased gradually along with embryo development process and reached a maximum number at hatching. Contrarily, the number of HGCs decreased gradually after hatching, and HGCs disappeared 5 hours after hatching. However, the intensity of HE-positive reaction was almost at the same level at the period of HGCs'presence. (6) Artemia HGCs were distributed throughout the body of embryos at all time during their presence. Therefore, it can concluded that Artemia HGCs, as a transient type of cells, first appeared in embryos 4 hours before hatching and disappeared in embryos 5 hours after hatching, and with distinguished patterns of appearance, disappearance and

Eight-Shaped Hatching Increases the Risk of Inner Cell Mass Splitting in Extended Mouse Embryo Culture.

Directory of Open Access Journals (Sweden)

Zheng Yan

Full Text Available Increased risk of monozygotic twinning (MZT has been shown to be associated with assisted reproduction techniques, particularly blastocyst culture. Interestingly, inner cell mass (ICM splitting in human '8'-shaped hatching blastocysts that resulted in MZT was reported. However, the underlying cause of MZT is not known. In this study, we investigated in a mouse model whether in vitro culture leads to ICM splitting and its association with hatching types. Blastocyst hatching was observed in: (i in vivo developed blastocysts and (ii-iii in vitro cultured blastocysts following in vivo or in vitro fertilization. We found that '8'-shaped hatching occurred with significantly higher frequency in the two groups of in vitro cultured blastocysts than in the group of in vivo developed blastocysts (24.4% and 20.4% versus 0.8%, respectively; n = 805, P < 0.01. Moreover, Oct4 immunofluorescence staining was performed to identify the ICM in the hatching and hatched blastocysts. Scattered and split distribution of ICM cells was observed around the small zona opening of '8'-shaped hatching blastocysts. This occurred at a high frequency in the in vitro cultured groups. Furthermore, we found more double OCT4-positive masses, suggestive of increased ICM splitting in '8'-shaped hatching and hatched blastocysts than in 'U'-shaped hatching and hatched blastocysts (12.5% versus 1.9%, respectively; n = 838, P < 0.01. Therefore, our results demonstrate that extended in vitro culture can cause high frequencies of '8'-shaped hatching, and '8'-shaped hatching that may disturb ICM herniation leading to increased risk of ICM splitting in mouse blastocysts. These results may provide insights into the increased risk of human MZT after in vitro fertilization and blastocyst transfer.

Host Status of Different Potato (Solanum tuberosum) Varieties and Hatching in Root Diffusates of Globodera ellingtonae.

Science.gov (United States)

Zasada, Inga A; Peetz, Amy; Wade, Nadine; Navarre, Roy A; Ingham, Russ E

2013-09-01

Globodera ellingtonae was detected in Oregon in 2008. In order to make decisions regarding the regulation of this nematode, knowledge of its biology is required. We determined the host status of a diversity of potato (Solanum tuberosum) varieties in soil-based experiments and identified hatching stimulants in in vitro hatching assays. 'Russet Burbank,' 'Desiree,' 'Modac,' 'Norland,' 'Umatilla,' and 'Yukon Gold' were good hosts (RF > 14) for G. ellingtonae. Potato varieties 'Maris Piper,' 'Atlantic,' and 'Satina,' all which contain the Ro1 gene that confers resistance to G. rostochiensis, were not hosts for G. ellingtonae. In in vitro hatching assays, G. ellingtonae hatched readily in the presence of diffusates from potato (PRD) and tomato (Solanum lycopersicum; TRD). Egg hatch occurred in an average of between 87% and 90% of exposed cysts, with an average of between 144 and 164 juveniles emerging per cyst, from PRD- and TRD-treated cysts, respectively. This nematode hatched rapidly in the presence of PRD and TRD, with at least 66% of total hatch occurring by day 3 of exposure. There was no dose-response of egg hatch to concentrations of PRD or TRD ranging from 1:5 to 1:100 diffusate to water. When G. ellingtonae was exposed to root diffusates from 21 different plants, hatch occurred in 0% to 70% of exposed cysts, with an average of between 0 to 27 juveniles emerging per cyst. When root diffusate-exposed cysts were subsequently transferred to PRD to test viability, root diffusates from arugula (Eruca sativa), sudangrass (Sorghum bicolor subsp. drummondii), and common vetch (Vicia sativa) continued to inhibit egg hatch compared with the other root diffusates or water in which hatch occurred readily (60 to 182 juveniles emerging per cyst). Previously known hatching stimulants of G. rostochiensis and G. pallida, sodium metavanadate, sodium orthovanadate, and sodium thiocyanate, stimulated some egg hatch. Although, Globodera ellingtonae hatched readily in PRD and TRD

Heavier chicks at hatch improves marketing body weight by enhancing skeletal muscle growth.

Science.gov (United States)

Sklan, D; Heifetz, S; Halevy, O

2003-11-01

This study examined some of the factors connected with the greater marketing weight observed in chicks hatching with higher BW. Examination of chicks hatching from maternal flocks of different ages indicated that BW at hatch increased quadratically and yolk sac weight linearly with age, whereas components of the gastrointestinal tract showed no significant trend. Growth of pectoralis muscles and gastrointestinal tract were compared in chicks hatching at the same weight from maternal flocks of 28 and 64 wk of age and in chicks from the same maternal flock (44 wk old) hatching at different weights. The results indicated that no differences were found among chicks hatching with the same weight from maternal flocks of different ages. In contrast, in chicks from the same maternal flock hatching at different weights the gastrointestinal tract tended to compose a smaller proportion of BW in large chicks, and its growth was not correlated with performance. Liver proportions were greater in heavier chicks. Pectoralis growth and satellite cell numbers and activity were greater in heavier chicks through 5 d posthatch, and pectoralis muscles were heavier at marketing. Examination of some of the growth factors involved suggested that in heavier chicks satellite cells underwent higher proliferation and earlier differentiation during their critical period of activity in the immediate posthatch days. To determine when these differences in activity were established, examination of 15-d embryonic myoblast activity indicated that at this stage activity was already greater in the heavier eggs. This finding suggests that programming of muscle growth may be completed in late embryonic stages. This study suggests that enhanced satellite cell activity is involved in increased growth of chicks hatching with higher BW.

Effects of egg weight on hatchability, chick hatch-weight and ...

African Journals Online (AJOL)

Egg weight was positively and strongly correlated with egg hatchability (r2 = 0.727) and chick hatch-weight (r2 = 0.953). Heavier-sized eggs hatched chicks had higher mortality rates. Growth rate and live weight of the chickens were optimized at different egg weights of 56 (r2 = 0.657) and 60 (r2 = 0.870) g, respectively, ...

The Effect of Eggshell Thickness on Hatching Traits of Partridges

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US Yamak

Full Text Available ABSTRACT Incubation is an important factor in poultry production, particularly in species with relatively low fertility and hatchability rates. This study examined the effect of eggshell thickness on hatching traits of partridges (A. chukar. A total of 462 eggs from intensively reared partridges were separated into three groups according to eggshell thickness, which was measured ultrasonically before incubation. Hatchability, chick weight, and chick length were assessed at the end of the incubation period. Hatching times were recorded during hatching. Embryonic mortalities in unhatched eggs were classified according to mortality stage at the end of incubation. The effect of eggshell thickness on hatchability was found to be insignificant for all groups. Moreover, eggshell thickness had no significant effect on chick weight or length.

Hatching asynchrony aggravates inbreeding depression in a songbird (Serinus canaria): an inbreeding-environment interaction.

Science.gov (United States)

de Boer, Raïssa A; Eens, Marcel; Fransen, Erik; Müller, Wendt

2015-04-01

Understanding how the intensity of inbreeding depression is influenced by stressful environmental conditions is an important area of enquiry in various fields of biology. In birds, environmental stress during early development is often related to hatching asynchrony; differences in age, and thus size, impose a gradient in conditions ranging from benign (first hatched chick) to harsh (last hatched chick). Here, we compared the effect of hatching order on growth rate in inbred (parents are full siblings) and outbred (parents are unrelated) canary chicks (Serinus canaria). We found that inbreeding depression was more severe under more stressful conditions, being most evident in later hatched chicks. Thus, consideration of inbreeding-environment interactions is of vital importance for our understanding of the biological significance of inbreeding depression and hatching asynchrony. The latter is particularly relevant given that hatching asynchrony is a widespread phenomenon, occurring in many bird species. The exact causes of the observed inbreeding-environment interaction are as yet unknown, but may be related to a decrease in maternal investment in egg contents with laying position (i.e. prehatching environment), or to performance of the chicks during sibling competition and/or their resilience to food shortage (i.e. posthatching environment). © 2015 The Author(s).

Egg clutch dehydration induces early hatching in red-eyed treefrogs, Agalychnis callidryas

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María José Salica

2017-07-01

Full Text Available Terrestrial eggs have evolved repeatedly in tropical anurans exposing embryos to the new threat of dehydration. Red-eyed treefrogs, Agalychnis callidryas, lay eggs on plants over water. Maternally provided water allows shaded eggs in humid sites to develop to hatching without rainfall, but unshaded eggs and those in less humid sites can die from dehydration. Hatching responses of amphibian eggs to dry conditions are known from two lineages with independent origins of terrestrial eggs. Here, we experimentally tested for dehydration-induced early hatching in another lineage (Agalychnis callidryas, Phyllomedusidae, representing a third independent origin of terrestrial eggs. We also investigated how dehydration affected egg and clutch structure, and egg mortality. We collected clutches from a pond in Gamboa, Panama, and randomly allocated them to wet or dry treatments at age 1 day. Embryos hatched earlier from dry clutches than from wet clutches, accelerating hatching by ∼11%. Clutch thickness and egg diameter were affected by dehydration, diverging between treatments over time. Meanwhile, mortality in dry clutches was six-fold higher than in control clutches. With this study, early hatching responses to escape mortality from egg dehydration are now known from three anuran lineages with independent origins of terrestrial eggs, suggesting they may be widespread. Further studies are needed to understand how terrestrial amphibian eggs can respond to, or will be affected by, rapid changes in climate over the next decades.

Organic and inorganic selenium in Aseel chicken diets: Effect on hatching traits.

Science.gov (United States)

Khan, M T; Mahmud, A; Zahoor, I; Javed, K

2017-05-01

A study was conducted to evaluate the effect of dietary selenium (Se) sources (organic and inorganic Se at 0.30 ppm and basal diet at 0 ppm level of supplemented Se) on hatching traits in four varieties of Aseel chicken, Lakha, Mushki, Peshawari, and Mianwali. In total, 84 adult molted hens (50 wk old), 21 from each variety, were randomly assigned to 12 treatment groups in a 3 (Se diets) × 4 (Aseel varieties) factorial arrangement under a randomized complete block design. Each treatment was replicated 7 times with individual hens in each. Settable egg, fertility, hatch of fertile eggs, hatchability, A-grade chick, and embryonic mortality parameters were evaluated. The results indicated that the birds fed an organic Se supplemented diet had greater (P < 0.05) settable eggs, fertility, hatch of fertile eggs, hatchability, and A-grade chicks and reduced embryonic mortality than those fed inorganic or no Se. Among varieties, Mushki had lower (P < 0.05) fertility, hatch of fertile eggs, hatchability, and A-grade chicks than rest of three varieties. Interaction of Se sources and varieties indicated that dietary organic Se supplementation improved (P < 0.05) hatch of fertile eggs in Peshawari and Mianwali, whereas hatchability only in Peshawari variety and reduced embryonic mortality in Mianwali. It was concluded that dietary supplementation of organic Se could be used to improve hatching traits as well as reduce embryonic mortality in native Aseel chicken. © 2016 Poultry Science Association Inc.

Efficiency of assisted hatching of the cryopreserved–melted embryos

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V. A. Pitko

2018-04-01

Full Text Available Purpose. To measure outcomes of clinical research of efficiency of assisted hatching of cryopreserved embryos. Materials and methods. Patients who had un successful cycles IVF/ICSI with transfer of fresh embryos have been selected for participation in the research between 2014 and 2016 years. Patients were distributed in a random way for participation in the experiment and control groups. Results of embryos transfer of one or two cryopreserved and melted embryos were considered only. Embryos were cryopreserved at a stage of blastocyst, 5 days after extraction of oocytes by method of vitrification. Melting procedure was conducted in the morning of a day of embryos transfer following the instructions of the vitrification medium producer Cryotech (Japan. Assisted hatching was conducted with use of micropipettes of Holding Pipette Cook Medical (Australia and Assisted Hatching/Zona Drilling Pipette Cook Medical (Australia. The treated embryos were cultivated up to a repeated estimation of morphology of embryos before transfer. Transfer of embryos has been conducted by a standard method with the use of catheter for non-invasive transfer of embryo Sydney IVF Cook Medical (Australia. The quantity of the transferred embryos varied from one to two. Results. 100 cryopreserved embryos were transferred which have been distributed in a random way either to the group with the assisted hatching or to the control group (without assisted hatching. A number of parameters of patients from both groups was analyzed, i.e. age of the patient at the time of melting of embryos, duration of infertility, causes of infertility, quantity of previous unsuccessful cycles IVF/ICSI. Any essential differences between patients within two groups based on the aforementioned parameters were not revealed. Also, there were no essential differences in number of the melted embryos, survival rate of embryos, quantity of the embryos transferred to patients. However, at the same time

essential oil as hatching egg disinfectant

African Journals Online (AJOL)

STORAGESEVER

2010-04-26

Apr 26, 2010 ... disinfectant for hatching egg obtained from broiler breeder flock. Oregano essential ... contamination rate, hatchability of fertile egg, body weight at 21 and 42 days, body weight gain and total feed ... successful healthy hatchlings. Several ...... Insecticidal properties of essential plant oils against the mosquito.

Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.

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Mark Allan Ditmer

Full Text Available Current understanding of the factors influencing hawksbill sea turtle (Eretmochelys imbricata hatch success is disparate and based on relatively short-term studies or limited sample sizes. Because global populations of hawksbills are heavily depleted, evaluating the parameters that impact hatch success is important to their conservation and recovery. Here, we use data collected by the Jumby Bay Hawksbill Project (JBHP to investigate hatch success. The JBHP implements saturation tagging protocols to study a hawksbill rookery in Antigua, West Indies. Habitat data, which reflect the varied nesting beaches, are collected at egg deposition, and nest contents are exhumed and categorized post-emergence. We analyzed hatch success using mixed-model analyses with explanatory and predictive datasets. We incorporated a random effect for turtle identity and evaluated environmental, temporal and individual-based reproductive variables. Hatch success averaged 78.6% (SD: 21.2% during the study period. Highly supported models included multiple covariates, including distance to vegetation, deposition date, individual intra-seasonal nest number, clutch size, organic content, and sand grain size. Nests located in open sand were predicted to produce 10.4 more viable hatchlings per clutch than nests located >1.5 m into vegetation. For an individual first nesting in early July, the fourth nest of the season yielded 13.2 more viable hatchlings than the initial clutch. Generalized beach section and inter-annual variation were also supported in our explanatory dataset, suggesting that gaps remain in our understanding of hatch success. Our findings illustrate that evaluating hatch success is a complex process, involving multiple environmental and individual variables. Although distance to vegetation and hatch success were inversely related, vegetation is an important component of hawksbill nesting habitat, and a more complete assessment of the impacts of specific

46 CFR 35.30-10 - Cargo tank hatches, ullage holes, and Butterworth plates-TB/ALL.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Cargo tank hatches, ullage holes, and Butterworth plates... OPERATIONS General Safety Rules § 35.30-10 Cargo tank hatches, ullage holes, and Butterworth plates—TB/ALL. No cargo tank hatches, ullage holes, or Butterworth plates shall be opened or shall remain open...

High Pressure Coolant Injection system risk-based inspection guide for Hatch Nuclear Power Station

International Nuclear Information System (INIS)

DiBiasio, A.M.

1993-05-01

A review of the operating experience for the High Pressure Coolant Injection (HPCI) system at the Hatch Nuclear Power Station, Units 1 and 2, is described in this report. The information for this review was obtained from Hatch Licensee Event Reports (LERs) that were generated between 1980 and 1992. These LERs have been categorized into 23 failure modes that have been prioritized based on probabilistic risk assessment considerations. In addition, the results of the Hatch operating experience review have been compared with the results of a similar, industry wide operating, experience review. This comparison provides an indication of areas in the Hatch HPCI system that should be given increased attention in the prioritization of inspection resources

In vitro hatching of Trichuris suis eggs

DEFF Research Database (Denmark)

Vejzagic, Nermina; Thamsborg, Stig Milan; Kringel, Helene

2015-01-01

Eggs of the pig whipworm, Trichuris suis ova (TSO), are currently tested in human clinical trials for their potential immunomodulatory capacity. The biological potency of TSO (egg viability and infectivity) is traditionally assessed in Göttingen minipigs as the establishment of intestinal larvae...... after inoculation with a known number of eggs. To minimize testing in animal models, development of an in vitro egg hatching assay is proposed as a reliable, cost-effective, and a faster alternative to test the egg viability. The present study aimed to investigate the influence of different chemical......, physical, and biological factors on egg hatching. Thus, in a series of experiments and in different combinations, the eggs were stimulated with glass beads, artificial gastric juice, bile salt and trypsin solution, fermentation gut medium, or stimulated with mucosal scrapings from the ileum and the large...

Hatching and larval export of the intertidal crab Neohelice granulata in Mar Chiquita coastal lagoon, Argentina

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Guillermina Sánchez Vuichard

2013-06-01

Full Text Available Synchronization in the events of the reproductive cycle in female Neohelice granulata Dana, 1851 were studied from samples taken weekly and biweekly from September to December 2006 in the Laguna Mar Chiquita. The timing and larval hatching and synchronicity were inferred from numbers of ovigerous females and observing the stages of embryonic development. Synchronization in larval hatching also was observed in females in experiments in dark for a period of 48 hours, at three different salinities (10, 23 and 33 ppm. In addition plankton sampling were performed in order to study larval exportation at the field and its link to the tidal and light/dark cycles. We found that ovigerous females of N. granulata have a marked synchronization in embryonic development which results in that most of berried females are close to hatching within a period of maximum tidal range (days. Within this period, there is a synchronization of hatching at a time scale of hours, governed by environmental conditions. The salinity range used in this study (10-32‰ did not affect hatching synchronicity neither time to hatch. Hatching was synchronized according to endogenous rhythms governed mainly by the tidal cycle and secondarily by the breadth of it. It is also conditioned by the light-dark cycle through an exogenous cycle, so that the hatchings would occur mostly at night high tides.

Egg Hatch Rate and Nymphal Survival of the Bed Bug (Hemiptera: Cimicidae) After Exposure to Insecticide Sprays.

Science.gov (United States)

Hinson, K R; Benson, E P; Zungoli, P A; Bridges, W C; Ellis, B R

2016-12-01

Few studies have addressed the efficacy of insecticides used against eggs and first-instar nymphs of the bed bug, Cimex lectularius L. (Hemiptera: Cimicidae). Insect eggs are often resistant to insecticides; therefore, information on which products are effective is important. We evaluated the efficacy of four commonly used insecticide sprays applied directly to bed bug eggs. We also evaluated the efficacy of these insecticides to first-instar nymphs exposed to residuals resulting from directly spraying eggs. Temprid SC (beta-cyfluthrin, imidacloprid) was the most effective insecticide at preventing egg hatch (13% hatch rate) for pyrethroid-resistant, field-strain (Jersey City) bed bugs compared with a control (water [99% hatch rate]), Bedlam (MGK-264, sumithrin [84% hatch rate]), Demand CS (lambda-cyhalothrin [91% hatch rate]), and Phantom SC (chlorfenapyr [95% hatch rate]). Demand CS and Temprid SC were most effective at preventing egg hatch (0%) for an insecticide-susceptible (Harold Harlan) strain, followed by Bedlam (28%). Phantom SC produced a hatch rate similar to the control (97% and 96%, respectively). Harold Harlan-strain nymphs showed 100% survival for the control but 0% survival for Bedlam and Phantom SC. Jersey City-strain nymphs showed 100% survival for the control, 99% survival for Bedlam, 0% survival for Demand CS, 4% survival for Phantom SC, and 38% survival for Temprid SC. Demand CS was less effective at preventing hatch (91% hatch rate) of Jersey City-strain nymphs but was the only product to kill all nymphs (0% survival). One of the least effective products for preventing Jersey City-strain egg hatch (Phantom SC, 95% hatch rate) was the second most effective at killing nymphs, leaving only six of 141 alive. These findings indicate that survival of directly sprayed eggs and residually exposed, first-instar nymphs varies by strain, life stage, and product used. © The Authors 2016. Published by Oxford University Press on behalf of Entomological

The effect of low changes in radiation dose on the hatching data of rainbow trout

International Nuclear Information System (INIS)

Buehringer, H.; Kellermann, H.J.

1993-01-01

Radiation hormesis hypothesis refers to the occurrence of a biphasic dose-respond relationship in which higher doses cause an inhibitory effect and lower doses cause a stimulatory effect. By extrapolation of this thesis there could be suggested a radiation damage effect below normal background radiation doses. Rainbow trout eggs, which are very radiation sensitive, were fertilized and incubated in environments with abient radiation (Hamburg), increased doses of radiation and decreased level of radiation doses (ASSE II). Hatching data (incubation time, hatching time, hatching success, number and kind of malformations, length of larvae) were examined for a hormesis effect. Only in hatching success a statistically significant effect of radiation dose was noticeable. (orig.) [de

Variation in the hatching response of Ochlerotatus albifasciatus egg batches (Diptera: Culicidae in temperate Argentina

Directory of Open Access Journals (Sweden)

Raúl Ernesto Campos

2006-02-01

Full Text Available Egg hatching of winter-collected Ochlerotatus albifasciatus was studied for six months. Batches of eggs were divided into two groups, one of them was stored in the laboratory at 23°C and 12:12 photoperiod, and the other in the field under dead leaves. Every month, from July to December, eggs from the two groups were flooded under both laboratory and field conditions. Unhatched eggs were returned to the original condition and flooded two more times separated by ten-day intervals. Results show that egg diapause is expressed in different intensities, not only on eggs exposed to different conditions but also in those exposed to the same condition, even when they were laid by the same female. Successive inundations yielded incomplete hatches of eggs, and favored the hatching response in the next flooding. Low environmental temperatures before and during the flooding depressed hatching response. This shows that eggs need a warm period before flooding as well as warm temperatures during flooding, to hatch. As drought period was longer hatching response increased, but this was also accompanied by warmer environmental conditions. The experiment performed in laboratory did not show that increment. Field studies showed that a layer of dead leaves protected eggs from extreme temperatures.

45 CFR 1226.10 - Hatch Act restrictions.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Hatch Act restrictions. 1226.10 Section 1226.10 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY... candidates on canvassing or speaking tours. (12) Participation in or organizing a political parade. (13...

Histological Characteristics of Leg Muscles of 56-Day Old Pheasants Hatched from Eggs of Different Eggshell Colour

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Dragan Zikic

2015-05-01

Full Text Available The aim of this paper was to examine the histological characteristics of leg muscles of pheasants hatched from eggs of a different colour. From muscle samples (M. biceps femoris of 56-day old pheasants hatched from eggs of different colour (dark brown, light brown, brown/green, blue/green histological preparations were made. Following parameters were examined: diameter of muscle cells, volume density of connective tissue in muscles, nucleo-cytoplasmatic ratio of muscle cells. Results showed that diameter of muscle cells was smaller in pheasants hatched from blue/green eggs compared to all other examinated groups. There was no differences in volume density of connective tissue in muscles between groups. Nucleo-cytoplasmatic ratio of muscle cells was higher in pheasants hatched from blue/green eggs compared to all other examinated groups. From obtained results it can be concluded that pheasants hatched from blue/green eggs had weaker muscle development than pheasants hatched from eggs of other eggshell colour. Cause of this could be related to structural differences of eggshells of various colour. This leads to weaker development of embryos and chicks hatched from blue/green eggs which reflects on differences in development of leg muscles.

Modelling the effect of temperature on hatching and settlement patterns of meroplanktonic organisms: the case of octopus

Directory of Open Access Journals (Sweden)

Stelios Katsanevakis

2006-12-01

Full Text Available The duration of embryonic development and the planktonic stage of meroplanktonic species is highly temperature dependent and thus the seasonal temperature oscillations of temperate regions greatly affect the patterns of hatching and benthic settlement. Based on data from the literature on embryonic development and planktonic duration of Octopus vulgaris (common octopus in relation to temperature, and on observed temperature patterns, several models of hatching and settlement patterns were created. There was a good fit between observed settlement patterns and model predictions. Based on these models we concluded that in temperate regions: (1 when temperature is increasing (from early spring to mid summer the hatching and settlement periods tend to shorten, while when the temperature is decreasing (during autumn the hatching and settlement periods tend to lengthen; (2 hatching and settlement peaks are narrower and more intense than a spring spawning peak but wider and less intense than an autumn spawning peak; (3 at lower latitudes, hatching and settlement patterns tend to follow the spawning pattern more closely, (4 the periodic temperature pattern of temperate areas has the potential to cause a convergence of hatching during spring.

Cold storage effects on egg hatch in laboratory-reared Culicoides variipennis sonorensis (Diptera: Ceratopogonidae).

Science.gov (United States)

Hunt, G J; Tabachnick, W J

1995-09-01

The effects of cold storage (5 degrees C) on the hatching rates of laboratory-reared Culicoides variipennis sonorensis eggs were examined. Mortality increased with storage time. Average maximum embryo survivorship for 4 trials was 55.0 +/- 4.2 (+/- SEM) days. Alternating daily cycles of high and then low mean hatching rates occurred and possibly were due to location differences in temperature within the temperature-controlled rearing system. During cold storage at 5 degrees C, C. v. sonorensis eggs may be kept for ca. 28 days with an anticipated hatching rate of about 50%.

Mortality of Parental Mountain Plovers (Charadrius montanus during the Post-hatching Stage.

Directory of Open Access Journals (Sweden)

Victoria J. Dreitz

2010-06-01

Full Text Available Monitoring, management, and conservation of grassland birds are topics of importance because of widespread population declines. Annual estimates of survival are available for many species, however knowledge of how survival varies on a seasonal basis remains poor. Information on the relative effects of breeding, overwintering, and migratory periods on population dynamics is necessary for effective management. Mortality risks often vary with the stage of the breeding cycle. In precocial species, mortality risks of adult birds are often higher during post-hatching care than prehatching. Using a multistate modeling approach, I investigated the influence of both environmental characteristics, measured by habitat, and individual characteristics, measured by sex and body mass, on post-hatching parental mortality of a declining grassland species, the Mountain Plover (Charadrius montanus. I found minimal evidence to support the effect of habitat, sex, or body mass on post-hatching parental mortality. Daily parental mortality was 0.0037 (SE = 0.0007, CI = 0.0026, 0.0053 and survival during the 30-day post-hatching period was 0.8943 (SE = 0.0187, CI = 0.8512, 0.9255. The findings from this study provide an understanding of the associations with today's grassland habitats and the dynamics of Mountain Plovers during the breeding season. Prior to assessing if alterations in habitats are acting more on post-hatching than the other stages of the annual cycle for the Mountain Plover, information on survival during other breeding stages and during migration is needed to assist in developing effective conservation and management plans.

Effect of in ovo injection of corticotropin-releasing hormone on the timing of hatching in broiler chickens.

Science.gov (United States)

Watanabe, Yugo; Grommen, Sylvia V H; De Groef, Bert

2017-09-01

In chicken embryos, intravenous injection of corticotropin-releasing hormone (CRH) causes the release of both corticosteroids and thyroid hormones. These hormones initiate and enhance the hatching process, raising the possibility that CRH treatment of the late chicken embryo could accelerate hatching and/or decrease the spread of hatching. We performed a series of exploratory tests to investigate whether in ovo delivery methods of CRH other than intravenous injection that are more practical in a commercial setting, affect hatching time in broilers. Corticotropin-releasing hormone was injected into the air cell, albumen, or amniotic fluid of broiler breeder eggs, in the last week of embryonic development. Average incubation duration was significantly decreased by 22 h when 2 μg of CRH was injected into the air cell on embryonic day 18 (E18) of Cobb eggs. Acceleration of hatching (but only by 8 h) was also seen for Ross chicks when CRH was injected daily into the albumen between E10 and E18. However, repeats of both experiments did not show consistent effects of CRH on hatching time; in most experiments performed, CRH did not affect hatching time. We speculate that the effectiveness of CRH uptake via these delivery methods and/or the duration and magnitude of the thyroxine and corticosterone response to CRH is not sufficient to have a substantial effect on hatching time. We therefore conclude that in ovo CRH treatment does not seem a feasible option as a practical tool to increase hatchery productivity or to investigate the effects of CRH agonists and antagonists on hatching. © 2017 Poultry Science Association Inc.

Effects of a combined hatching and brooding system on hatchability, chick weight, and mortality in broilers.

Science.gov (United States)

van de Ven, L J F; van Wagenberg, A V; Groot Koerkamp, P W G; Kemp, B; van den Brand, H

2009-11-01

Chicks hatch over a time window of approximately 36 to 48 h and are removed from the hatchers only when the majority of the chicks has hatched. Consequently, chicks are exposed to prolonged posthatch holding periods and delays in feed and water access, leading to dehydration and impaired posthatch performance. It is questionable whether the physiological requirements of the hatchlings can be met with current hatching systems. An alternative system that may better match the requirements of the hatchlings is a system that combines the hatching and brooding phase, so that feed and water can be provided immediately after hatch. Such a system, named Patio, was developed in the Netherlands and tested from 2006 to 2008, to evaluate effects on hatchability and early performance of broilers. This paper describes the Patio system and the results from these tests. A total of 21 broiler production trials (780,686 eggs) in the Patio system were evaluated at 3 locations and compared with control hatches of eggs of the same parental flock in the hatchery. Hatchability in the Patio was on average 1.45, 1.83, and 1.86% higher at location 1, 2, and 3, respectively. However, in the calculation of the hatchability in the Patio, possible second grade chicks were included, whereas these were excluded in the calculation of hatchability in the hatchery. Additionally, in the hatchery, the hatching process was interrupted earlier than in the Patio, meaning that possible late hatching chicks remained in the flock in the Patio, but not in the hatchery. In 3 trials, the Patio chicks were 11.6 to 16.3% heavier at d 0, when the hatchery chicks were placed in the broiler house. Mean cumulative 7-d mortality was only assessed in the Patio and was 1.27, 1.09, and 1.43% at location 1, 2, and 3, respectively. The Patio system appears to function as an alternative to current hatching and brooding systems. Further studies are required to determine to what extent the higher hatchability is due to second

Critical review of the equipment hatch of a large dry steel containment. The DEFENDER IMPROVEMENT

International Nuclear Information System (INIS)

Mantega, F.; Penno, E.; Vanini, P.

1994-01-01

Performances of the Containment System under Severe Accident conditions depend on a number of different features and components. The equipment hatch may be considered a critical component because it is a potential main contributor to the total Containment leak rate during a Severe accident and a potential (depending on the design) direct leak path between the containment atmosphere and the environment. The analytical study performed to anticipate the response of the equipment hatch of a large dry steel containment under Severe Accident condition has pointed out some questions of concern. The possible leak tightness failure mechanism are related to: the gaskets elastic characteristics degradation due to thermal and radiological aging; the deformation of the hatch sleeve induced by the containment wall; and the differential expansion between gasket material and steel. Beside, the equipment hatch may be considered a single barrier and although it is equipped with two gaskets, it is not difficult to demonstrate that a backup function cannot be assigned to the external gasket. For these reason it seems to be necessary to realize a wider application of the 'Defence in Depth' criteria in the design of this component. The DEFENDER (DEFENce in Depth Equipment hatch Requalification) might be a solution to increase the margin of safety of the equipment hatch under the Severe Accident condition. (author)

Commercially laid eggs vs. discarded hatching eggs: contamination by Salmonella spp.

Science.gov (United States)

Kottwitz, Luciana B M; Leão, Joice Aparecida; Back, Alberto; Rodrigues, Dalia dos P; Magnani, Marciane; de Oliveira, Tereza C R M

2013-01-01

Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.

THE RELATIONSHIP BETWEEN MASS OF NEWLY HATCHED INDIVIDUALS AND COCOON MASS IN LUMBRICID EARTHWORMS

DEFF Research Database (Denmark)

Bruus, Marianne; Bjerre, Arne

1991-01-01

Earthworm cocoons from laboratory cultures were collected and their mass was determined. When hatched, the mass of the young worms was found. Cocoon mass and the mass of hatchlings varied considerably within species. The hygromass of newly hatched earthworms was found to correlate linearly...

Chick Development and Asynchroneous Hatching in the Zebra Finch (Taeniopygia guttata castanotis).

Science.gov (United States)

Ikebuchi, Maki; Okanoya, Kazuo; Hasegawa, Toshikazu; Bischof, Hans-Joachim

2017-10-01

The mode of hatching in birds has important impacts on both parents and chicks, including the costs and risks of breeding for parents, and sibling competition in a clutch. Birds with multiple eggs in a single clutch often begin incubating when most eggs are laid, thereby reducing time of incubation, nursing burden, and sibling competition. In some songbirds and some other species, however, incubation starts immediately after the first egg is laid, and the chicks thus hatch asynchronously. This may result in differences in parental care and in sibling competition based on body size differences among older and younger chicks, which in turn might produce asynchronous development among siblings favoring the first hatchling, and further affect the development and fitness of the chicks after fledging. To determine whether such processes in fact occur in the zebra finch, we observed chick development in 18 clutches of zebra finches. We found that there were effects of asynchronous hatching, but these were smaller than expected and mostly not significant. Our observations suggest that the amount of care given to each chick may be equated with such factors as a camouflage effect of the down feathers, and that the low illumination within the nest also complicates the determination of the hatching order by the parents.

Post-hatching development of the porcine and bovine embryo-defining criteria for expected development in vivo and in vitro

DEFF Research Database (Denmark)

Vejlsted, Morten; Du, Yutao; Vajta, Gábor

2006-01-01

) Somite stage(s) where paraxial mesoderm gradually condensates to form somites. Post-hatching development of bovine embryos in vitro is compromised and although hatching occurs and elongation can be physically provoked by culture in agarose tunnels, the embryonic disk characterizing the pre-streak stage 1......Particular attention has been paid to the pre-hatching period of embryonic development although blastocyst development is a poor indicator of embryo viability. Post-hatching embryonic dev elopment in vitro would allow for establishment of more accurate tools for evaluating developmental potential...... without the need for transfer to recipient animals. Such a system would require (1) definition of milestones of expected post-hatching embryonic development in vivo; and (2) development of adequate culture systems. We propose a stereomicroscopical staging system for post-hatching embryos defining...

Intraspecific priority effects modify compensatory responses to changes in hatching phenology in an amphibian.

Science.gov (United States)

Murillo-Rincón, Andrea P; Kolter, Nora A; Laurila, Anssi; Orizaola, Germán

2017-01-01

In seasonal environments, modifications in the phenology of life-history events can alter the strength of time constraints experienced by organisms. Offspring can compensate for a change in timing of hatching by modifying their growth and development trajectories. However, intra- and interspecific interactions may affect these compensatory responses, in particular if differences in phenology between cohorts lead to significant priority effects (i.e. the competitive advantage that early-hatching individuals have over late-hatching ones). Here, we conducted a factorial experiment to determine whether intraspecific priority effects can alter compensatory phenotypic responses to hatching delay in a synchronic breeder by rearing moor frog (Rana arvalis) tadpoles in different combinations of phenological delay and food abundance. Tadpoles compensated for the hatching delay by speeding up their development, but only when reared in groups of individuals with identical hatching phenology. In mixed phenology groups, strong competitive effects by non-delayed tadpoles prevented the compensatory responses and delayed larvae metamorphosed later than in single phenology treatments. Non-delayed individuals gained advantage from developing with delayed larvae by increasing their developmental and growth rates as compared to single phenology groups. Food shortage prolonged larval period and reduced mass at metamorphosis in all treatments, but it did not prevent compensatory developmental responses in larvae reared in single phenology groups. This study demonstrates that strong intraspecific priority effects can constrain the compensatory growth and developmental responses to phenological change, and that priority effects can be an important factor explaining the maintenance of synchronic life histories (i.e. explosive breeding) in seasonal environments. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Characteristics of Skeletal Musculature of Pheasants Hatched from Eggs of Different Eggshell Colour

Directory of Open Access Journals (Sweden)

Dragan Zikic

2016-05-01

Full Text Available The aim of this paper was to examine morphodinamics of development of skeletal musculature of pheasants hatched from eggs of different eggshell colour. Four groups of pheasant eggs (dark brown, light brown, brown/green and blue/green were incubated. Samples of skeletal musculature of leg and breast were taken during the embryonic and neonatal period of development. From taken samples histological preparations were made. In pheasants hatched from blue/green eggs the smaller diameter of leg and breast muscle cells and the higher volume density of connective tissue in leg and breast muscles were recorded. It was concluded that pheasants hatched from blue/green eggs had the weakest development of skeletal musculature, which can be related to structural differences of eggshell of various colour.

Social Support, Depression, Self-Esteem, and Coping Among LGBTQ Adolescents Participating in Hatch Youth.

Science.gov (United States)

Wilkerson, J Michael; Schick, Vanessa R; Romijnders, Kim A; Bauldry, Jessica; Butame, Seyram A

2017-05-01

Evidence-based interventions that increase social support have the potential to improve the health of lesbian, gay, bisexual, transgender, and queer (LGBTQ) youth. Hatch Youth is a group-level intervention that provides services four nights a week to LGBTQ youth between 13 and 20 years of age. Each Hatch Youth meeting is organized into three 1-hour sections: unstructured social time, consciousness-raising (education), and a youth-led peer support group. Youth attending a Hatch Youth meeting between March and June 2014 (N = 108) completed a cross-sectional survey. Covariate adjusted regression models were used to examine the association between attendance, perceived social support, depressive symptomology, self-esteem, and coping ability. Compared to those who attended Hatch Youth for less than 1 month, participants who attended 1 to 6 months or more than 6 months reported higher social support (β 1-6mo. = 0.57 [0.07, 1.07]; β 6+mo. = 0.44, 95% confidence interval [CI; 0.14, 0.75], respectively). Increased social support was associated with decreased depressive symptomology (β = -4.84, 95% CI [-6.56, -3.12]), increased self-esteem (β = 0.72, 95% CI [0.38, 1.06]), and improved coping ability (β = 1.00, 95% CI [0.66, 1.35]). Hatch Youth is a promising intervention that has the potential to improve the mental health and reduce risk behavior of LGBTQ youth.

Hatching success in brackish water of Perca fluviatilis eggs obtained from the western Baltic Sea

DEFF Research Database (Denmark)

Christensen, Emil Aputsiaq Flindt; Skovrind, Mikkel; Olsen, Morten Tange

2016-01-01

tolerance of the eggs in vivo, and the salinities at which some populations spawn in situ (7 vs. 9.6 ‰). In the present study, hatching success of perch was determined in vivo for a Danish, western Baltic, brackish water population at salinities of 4, 7, 10 and 12 ‰. Furthermore, in order to place...... the population genetically among other European perch populations, individual egg samples were sequenced for a 390 base pair fragment of the mtDNA Dloop region. Hatching occurred at all four salinities, with no statistical differences among treatments. Successful hatching at 12 ‰ is well above salinities of 7......‰, which has previously been the highest reported from in vivo studies. This discrepancy is likely to be a result of methodological differences (e.g. different temperature) or perhaps interspecific variability in egg hatching abilities among perch populations. The perch from the present study consisted...

Cyst quality and hatching in parthenogenetic brine shrimp, Artemia

Digital Repository Service at National Institute of Oceanography (India)

Royan, J.P.; Sumitra-Vijayaraghavan; Krishnakumari, L.; Ramaiah, N.

) enhance the percentage of hatching of the cysts. On the basis of naupliar size, low ash content and high protein content it can be suggested that this strain is likely to be preferred by predators...

Spawning Characteristics and Artificial Hatching of Female Mottled Skate, Beringraja pulchra in the West Coast of Korea.

Science.gov (United States)

Kang, Hee-Woong; Jo, Yeong-Rok; Kang, Duk-Yong; Jeong, Gyeong-Suk; Jo, Hyun-Su

2013-09-01

The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 ㎝ in disc width, we found the spawning peak was between April to June, and the appearance ratio of egg capsules was the highest in May (32.1%). The eggs were hatched at 8°C, 13°C, 18°C, water temperature (12.8 to 24.2°C), and the best hatching temperature was 18°C. The number of fish hatched was 4 to 5 fish/egg capsules, and the hatching rate was 100%. The sex ratios of hatching larvae were 45.5% female and 54.5% male. Therefore this study will provide fundamental data and information for artificial reproduction of the mottled skate.

Effects of Different Hatcher Temperatures on Hatching Traits of ...

African Journals Online (AJOL)

selcuk

of genetic improvements in the modern broilers, the incubation conditions and ... development of the different organs and body structures of the embryo in time, and .... (hatching time, hatchability of fertile eggs, mortality stages and embryo ...

49 CFR 231.28 - Box and other house cars with roof hatches built or placed in service after October 1, 1966.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Box and other house cars with roof hatches built... RAILROAD SAFETY APPLIANCE STANDARDS § 231.28 Box and other house cars with roof hatches built or placed in... other house cars with roof hatches. Box and other house cars with roof hatches built on or before April...

The light cycle controls the hatching rhythm in Bombyx mori via negative feedback loop of the circadian oscillator.

Science.gov (United States)

Tao, Hui; Li, Xue; Qiu, Jian-Feng; Liu, Heng-Jiang; Zhang, Da-Yan; Chu, Feng; Sima, Yanghu; Xu, Shi-Qing

2017-10-01

Hatching behavior is a key target in silkworm (Bombyx mori) rearing, especially for the control of Lepidoptera pests. According to previous research, hatching rhythms appear to be controlled by a clock mechanism that restricts or "gates" hatching to a particular time. However, the underlying mechanism remains elusive. Under 12-h light:12-h dark photoperiod (LD) conditions, the transcriptional levels of the chitinase5 (Cht5) and hatching enzyme-like (Hel) genes, as well as the enzymatic activities of their gene products, oscillated in time with ambient light cycles, as did the transcriptional levels of the cryptochrome 1, cryptochrome 2, period (per), and timeless genes, which are key components of the negative feedback loop of the circadian rhythm. These changes were related to the expression profile of the ecdysteroid receptor gene and the hatching behavior of B. mori eggs. However, under continuous light or dark conditions, the hatching behavior, the expression levels of Cht5 and Hel, as well as the enzymatic activities of their gene products, were not synchronized unlike under LD conditions. In addition, immunohistochemistry experiments showed that light promoted the translocation of PER from the cytoplasm to the nucleus. In conclusion, LD cycles regulate the hatching rhythm of B. mori via negative feedback loop of the circadian oscillator. © 2017 Wiley Periodicals, Inc.

Post-hatching development of the porcine and bovine embryo-defining criteria for expected development in vivo and in vitro

DEFF Research Database (Denmark)

Vejlsted, Morten; Du, Yutao; Vajta, Gábor

2006-01-01

without the need for transfer to recipient animals. Such a system would require (1) definition of milestones of expected post-hatching embryonic development in vivo; and (2) development of adequate culture systems. We propose a stereomicroscopical staging system for post-hatching embryos defining......Particular attention has been paid to the pre-hatching period of embryonic development although blastocyst development is a poor indicator of embryo viability. Post-hatching embryonic dev elopment in vitro would allow for establishment of more accurate tools for evaluating developmental potential...

Interactions between hatch dates, growth rates, and mortality of Age-0 native Rainbow Smelt and nonnative Alewife in Lake Champlain

Science.gov (United States)

Parrish, Donna; Simonin, Paul W.; Rudstam, Lars G.; Pientka, Bernard; Sullivan, Patrick J.

2016-01-01

Timing of hatch in fish populations can be critical for first-year survival and, therefore, year-class strength and subsequent species interactions. We compared hatch timing, growth rates, and subsequent mortality of age-0 Rainbow Smelt Osmerus mordax and Alewife Alosa pseudoharengus, two common open-water fish species of northern North America. In our study site, Lake Champlain, Rainbow Smelt hatched (beginning May 26) almost a month earlier than Alewives (June 20). Abundance in the sampling area was highest in July for age-0 Rainbow Smelt and August for age-0 Alewives. Late-hatching individuals of both species grew faster than those hatching earlier (0.6 mm/d versus 0.4 for Rainbow Smelt; 0.7 mm/d versus 0.6 for Alewives). Mean mortality rate during the first 45 d of life was 3.4%/d for age-0 Rainbow Smelt and was 5.5%/d for age-0 Alewives. Alewife mortality rates did not differ with hatch timing but daily mortality rates of Rainbow Smelt were highest for early-hatching fish. Cannibalism is probably the primary mortality source for age-0 Rainbow Smelt in this lake. Therefore, hatching earlier may not be advantageous because the overlap of adult and age-0 Rainbow Smelt is highest earlier in the season. However, Alewives, first documented in Lake Champlain in 2003, may increase the mortality of age-0 Rainbow Smelt in the summer, which should favor selection for earlier hatching.

Production traits of artificially and naturally hatched geese in intensive and free-range systems: I. Growth traits.

Science.gov (United States)

Boz, M A; Sarica, M; Yamak, U S

2017-04-01

1. This study investigated the effect of incubation type and production system on geese growth traits. 2. A total of 216 geese were either naturally (114) or artificially (102) hatched and reared in intensive or free-range production systems (4 replicates each) until 18 weeks of age. 3. Weights of naturally hatched goslings (NHG) were significantly higher than artificially hatched goslings (AHG) at 2 weeks (644 vs. 536 g); however, weights of AHG were significantly higher than NHG at both 6 weeks (3245 vs. 3010 g) and 18 weeks (5212 vs. 4353 g). 4. AHG had better feed conversion ratios (FCRs) than NHG (6.21 vs. 6.46 at 18 weeks). Feed consumption of naturally hatched geese was found higher in first 4 weeks when compared to artificially hatched geese and artificially hatched geese consumed more feed than naturally hatched geese after 8 weeks. 5. Production system had insignificant effects on feed consumption, FCRs, viability and mutilation rates. 6. Slipped wings were more frequent in NHG than AHG (8.32% vs. 1.68% at 6 weeks; 23.84% vs. 5.12% between 7 and 18 weeks) and in free-range production when compared to intensive production (17.88% vs. 11.08% over the course of the production period). 7. The study results indicate that both artificially and NHG can be reared in free-range production systems without any loss in performance and in deference to animal welfare.

Influence of incubation management on pipping position, hatching ...

African Journals Online (AJOL)

Influence of incubation management on pipping position, hatching ability and survival of ostrich chicks. Z Brand, SWP Cloete, IA Malecki, CR Brown. Abstract. Despite numerous studies, the effect of artificial incubation on the hatchability and survival of near-term ostrich chicks is still not well understood. Records from 13 975 ...

Correlative and dynamic imaging of the hatching biology of Schistosoma japonicum from eggs prepared by high pressure freezing.

Directory of Open Access Journals (Sweden)

Malcolm K Jones

Full Text Available BACKGROUND: Schistosome eggs must traverse tissues of the intestine or bladder to escape the human host and further the life cycle. Escape from host tissues is facilitated by secretion of immuno-reactive molecules by eggs and the formation of an intense strong granulomatous response by the host which acts to exclude the egg into gut or bladder lumens. Schistosome eggs hatch on contact with freshwater, but the mechanisms of activation and hatching are poorly understood. In view of the lack of knowledge of the behaviour of egg hatching in schistosomes, we undertook a detailed dynamic and correlative study of the hatching biology of Schistosoma japonicum. METHODOLOGY/PRINCIPAL FINDINGS: Hatching eggs of S. japonicum were studied using correlative light and electron microscopy (EM. The hatching behaviour was recorded by video microscopy. EM preparative methods incorporating high pressure freezing and cryo-substitution were used to investigate ultrastructural features of the miracidium and extra-embryonic envelopes in pre-activated and activated eggs, and immediately after eggshell rupture. Lectin cytochemistry was performed on egg tissues to investigate subcellular location of specific carbohydrate groups. CONCLUSIONS/SIGNIFICANCE: The hatching of S. japonicum eggs is a striking phenomenon, whereby the larva is liberated explosively while still encapsulated within its sub-shell envelopes. The major alterations that occur in the egg during activation are scission of the outer envelope-eggshell boundary, autolysis of the cellular inner envelope, and likely hydration of abundant complex and simple polysaccharides in the lacunal space between the miracidial larva and surrounding envelopes. These observations on hatching provide insight into the dynamic activity of the eggs and the biology of schistosomes within the host.

Abundance of specific mRNA transcripts impacts hatching success in European eel, Anguilla anguilla L

DEFF Research Database (Denmark)

Rozenfeld, Christoffer; Butts, Ian A.E.; Tomkiewicz, Jonna

2016-01-01

-tubulin, insulin-like growth factor 2 (igf2), nucleoplasmin (npm2), prohibitin 2 (phb2), phosphatidylinositol glycan biosynthesis class F protein 5 (pigf5), and carnitine O-palmitoyltransferase liver isoform-like 1 (cpt1) are associated with embryonic developmental competence in other teleosts. Here, the relations...... and no hatching groups for any of the selected genes at 0, 2.5, and 5 HPF. However, at 30 HPF the hatch group showed significantly higher abundance of cpt1a, cpt1b, β-tubulin, phb2, and pigf5 transcripts than the no hatch group. Therefore, these results indicate that up-regulation of the transcription...

DIFFERENCES IN POST HATCH METABOLIC RATE AND DEVELOPMENTAL RATE IN ATLANTIC SALMON (SALMO SALAR L): EVIDENCE FOR COMPENSATORY GROWTH?

DEFF Research Database (Denmark)

Steffensen, John Fleng

2010-01-01

had higher VO2 compared to early hatching individuals at T1, but not at T2. Early and late hatchers were equally developed at T1and T2. Intra-family variation in time to hatching, suggests inherited parts of individual developmental rate. That late hatching larvae reached same level of development...

High temperatures and absence of light affect the hatching of resting eggs of Daphnia in the tropics

Directory of Open Access Journals (Sweden)

Thécia A.S.V. Paes

2016-03-01

Full Text Available Temperature and light are acknowledged as important factors for hatching of resting eggs. The knowledge of how they affect hatching rates of this type of egg is important for the comprehension of the consequences of warming waters in recolonization of aquatic ecosystems dependent on dormant populations. This study aimed at comparing the influence of different temperature and light conditions on hatching rates of Daphnia ambigua andDaphnia laevis resting eggs from tropical environments. The ephippia were collected in the sediment of three aquatic ecosystems, in southeastern Brazil. For each lake, the resting eggs were exposed to temperatures of 20, 24, 28 and 32 °C, under light (12 h photoperiod and dark conditions. The results showed that the absence of light and high temperatures have a negative influence on the hatching rates. Statistical differences for hatching rates were also found when comparing the studied ecosystems (ranging from 0.6 to 31%, indicating the importance of local environmental factors for diapause and maintenance of active populations.

Blood vessels segmentation of hatching eggs based on fully convolutional networks

Science.gov (United States)

Geng, Lei; Qiu, Ling; Wu, Jun; Xiao, Zhitao

2018-04-01

FCN, trained end-to-end, pixels-to-pixels, predict result of each pixel. It has been widely used for semantic segmentation. In order to realize the blood vessels segmentation of hatching eggs, a method based on FCN is proposed in this paper. The training datasets are composed of patches extracted from very few images to augment data. The network combines with lower layer and deconvolution to enables precise segmentation. The proposed method frees from the problem that training deep networks need large scale samples. Experimental results on hatching eggs demonstrate that this method can yield more accurate segmentation outputs than previous researches. It provides a convenient reference for fertility detection subsequently.

Sex Differences in Brain Thyroid Hormone Levels during Early Post-Hatching Development in Zebra Finch (Taeniopygia guttata.

Directory of Open Access Journals (Sweden)

Shinji Yamaguchi

Full Text Available Thyroid hormones are closely linked to the hatching process in precocial birds. Previously, we showed that thyroid hormones in brain had a strong impact on filial imprinting, an early learning behavior in newly hatched chicks; brain 3,5,3'-triiodothyronine (T3 peaks around hatching and imprinting training induces additional T3 release, thus, extending the sensitive period for imprinting and enabling subsequent other learning. On the other hand, blood thyroid hormone levels have been reported to increase gradually after hatching in altricial species, but it remains unknown how the brain thyroid hormone levels change during post-hatching development of altricial birds. Here, we determined the changes in serum and brain thyroid hormone levels of a passerine songbird species, the zebra finch using radioimmunoassay. In the serum, we found a gradual increase in thyroid hormone levels during post-hatching development, as well as differences between male and female finches. In the brain, there was clear surge in the hormone levels during development in males and females coinciding with the time of fledging, but the onset of the surge of thyroxine (T4 in males preceded that of females, whereas the onset of the surge of T3 in males succeeded that of females. These findings provide a basis for understanding the functions of thyroid hormones during early development and learning in altricial birds.

Sex Differences in Brain Thyroid Hormone Levels during Early Post-Hatching Development in Zebra Finch (Taeniopygia guttata).

Science.gov (United States)

Yamaguchi, Shinji; Hayase, Shin; Aoki, Naoya; Takehara, Akihiko; Ishigohoka, Jun; Matsushima, Toshiya; Wada, Kazuhiro; Homma, Koichi J

2017-01-01

Thyroid hormones are closely linked to the hatching process in precocial birds. Previously, we showed that thyroid hormones in brain had a strong impact on filial imprinting, an early learning behavior in newly hatched chicks; brain 3,5,3'-triiodothyronine (T3) peaks around hatching and imprinting training induces additional T3 release, thus, extending the sensitive period for imprinting and enabling subsequent other learning. On the other hand, blood thyroid hormone levels have been reported to increase gradually after hatching in altricial species, but it remains unknown how the brain thyroid hormone levels change during post-hatching development of altricial birds. Here, we determined the changes in serum and brain thyroid hormone levels of a passerine songbird species, the zebra finch using radioimmunoassay. In the serum, we found a gradual increase in thyroid hormone levels during post-hatching development, as well as differences between male and female finches. In the brain, there was clear surge in the hormone levels during development in males and females coinciding with the time of fledging, but the onset of the surge of thyroxine (T4) in males preceded that of females, whereas the onset of the surge of T3 in males succeeded that of females. These findings provide a basis for understanding the functions of thyroid hormones during early development and learning in altricial birds.

Inter-sexual differences in T-cell-mediated immunity of black-headed gull chicks (Larus ridibundus) depend on the hatching order

NARCIS (Netherlands)

Mueller, Wendt; Dijkstra, C; Groothuis, TGG

2003-01-01

Hatching asynchrony in avian species leads to age and size differences between nestlings within a brood, handicapping last-hatched chicks in the sibling rivalry. Starvation due to this competitive disadvantage has been regarded as the primary cause of an increase in mortality with hatching order.

Inheritance and world variation in thermal requirements for egg hatch in Lymantria dispar (Lepidoptera: Erebidae)

Science.gov (United States)

M.A. Keena

2016-01-01

Mode of inheritance of hatch traits in Lymantria dispar L. was determined by crossing populations nearly fixed for the phenotypic extremes. The nondiapausing phenotype was inherited via a single recessive gene and the phenotype with reduced low temperature exposure requirements before hatch was inherited via a single dominant gene. There was no...

Fathers modify thermal reaction norms for hatching success in Atlantic cod, Gadus morhua

DEFF Research Database (Denmark)

Dahlke, Flemming T.; Politis, Sebastian Nikitas; Butts, Ian

2016-01-01

hatching success significantly decreased towards thermal extremes. However, half-sibling families varied in their response to different incubation temperatures as indicated by significant paternity × temperature interactions and crossing of reaction norms. The influence of paternity itself was highly...... survival among half-sibling families and temperature treatments was observed during blastula and gastrulation stages (until 100% epiboly), while almost no mortality occurred during subsequent development and throughout the hatching period. The observed magnitude of genetic variation underlying thermal...

Effect of neutron irradiation on hatching rate of eggs and growth rate of chicken

International Nuclear Information System (INIS)

Liu Yubin; Zhao Jide; Liu Shengdian; Xy Xiuwei

1995-01-01

It was proved through 3 years of experiments and productions that after the eggs of AA meat chickens being irradiated by 14 MeV fast neutron, the hatching rate and the survival rate as well the weight of commercial chickens increased greatly. In addition it is found that the optimum neutron fluence for hatching and growth rate is 6.2 x 10 5 n·cm -2

Effect of hatch location and diet density on footpad dermatitis and growth performance in broiler chickens

NARCIS (Netherlands)

Jong, de I.C.; Lourens, A.; Harn, van J.

2015-01-01

The effect of hatch location and diet density on the prevalence of footpad dermatitis and growth performance in broiler chickenswas studied.Broilers (Ross 308), incubated at 2 different hatch locations but originating from the same parent stock,were subjected to 2 feeding programs differing in

An evolutionary insight into the hatching strategies of pipefish and seahorse embryos.

Science.gov (United States)

Kawaguchi, Mari; Nakano, Yuko; Kawahara-Miki, Ryouka; Inokuchi, Mayu; Yorifuji, Makiko; Okubo, Ryohei; Nagasawa, Tatsuki; Hiroi, Junya; Kono, Tomohiro; Kaneko, Toyoji

2016-03-01

Syngnathiform fishes carry their eggs in a brood structure found in males. The brood structure differs from species to species: seahorses carry eggs within enclosed brood pouch, messmate pipefish carry eggs in the semi-brood pouch, and alligator pipefish carry eggs in the egg compartment on abdomen. These egg protection strategies were established during syngnathiform evolution. In the present study, we compared the hatching mode of protected embryos of three species. Electron microscopic observations revealed that alligator pipefish and messmate pipefish egg envelopes were thicker than those of seahorses, suggesting that the seahorse produces a weaker envelope. Furthermore, molecular genetic analysis revealed that these two pipefishes possessed the egg envelope-digesting enzymes, high choriolytic enzyme (HCE), and low choriolytic enzyme (LCE), as do many euteleosts. In seahorses, however, only HCE gene expression was detected. When searching the entire seahorse genome by high-throughput DNA sequencing, we did not find a functional LCE gene and only a trace of the LCE gene exon was found, confirming that the seahorse LCE gene was pseudogenized during evolution. Finally, we estimated the size and number of hatching gland cells expressing hatching enzyme genes by whole-mount in situ hybridization. The seahorse cells were the smallest of the three species, while they had the greatest number. These results suggest that the isolation of eggs from the external environment by paternal bearing might bring the egg envelope thin, and then, the hatching enzyme genes became pseudogenized. J. Exp. Zool. (Mol. Dev. Evol.) 9999B:XX-XX, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Monitoring System and Temperature Controlling on PID Based Poultry Hatching Incubator

Science.gov (United States)

Shafiudin, S.; Kholis, N.

2018-04-01

Poultry hatching cultivation is essential to be observed in terms of temperature stability by using artificial penetration incubator which applies On/Off control. The On/Off control produces relatively long response time to reach steady-state conditions. Moreover, how the system works makes the component worn out because the lamp is on-off periodically. Besides, the cultivation in the market is less suitable to be used in an environment which has fluctuating temperature because it may influence plant’s temperature stability. The study aims to design automatic poultry hatching cultivation that can repair the temperature’s response of plant incubator to keep stable and in line with the intended set-point temperature value by using PID controller. The method used in PID controlling is designed to identify plant using ARX (Auto Regressive eXogenous) MATLAB which is dynamic/non-linear to obtain mathematical model and PID constants value that is appropriate to system. The hardware design for PID-based egg incubator uses Arduino Uno R3, as the main controller that includes PID source, and PWM, to keep plant temperature stability, which is integrated with incandescent light actuators and sensors where DHTI 1 sensor as the reader as temperature condition and plant humidity. The result of the study showed that PID constants value of each plant is different. For parallel 15 Watt plant, Kp = 3.9956, Ki = 0.361, Kd = 0, while for parallel 25 Watt plant, the value of Kp = 5.714, Ki = 0.351, Kd = 0. The PID constants value were capable to produce stable system response which is based on set-point with steady state error’s value is around 5%, that is 2.7%. With hatching percentage of 70-80%, the hatching process is successful in air-conditioned environment (changeable).

49 CFR 231.27 - Box and other house cars without roof hatches or placed in service after October 1, 1966.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Box and other house cars without roof hatches or... SAFETY APPLIANCE STANDARDS § 231.27 Box and other house cars without roof hatches or placed in service...) Number. (i) Each box or other house car without roof hatches shall be equipped with an efficient vertical...

Effect of electron irradiation in hatching eggs experimentally inoculated with salmonella enteriditis, on hatch ability and broiler performance

International Nuclear Information System (INIS)

Castaneda S, M.P.

1995-01-01

The effect of four doses of electrons irradaition on bacteriologic population in hatching egg following experimental shell contamination with Salmonella enteriditis phage type 13 was investigated. Fresh, whole, intact raw eggs were inoculated with 10 9 Colony-Forming Units of Salmonella enteriditis, eggs were irradiated with a beam electron source at either: 0.5, 1, 2 and 3 KGy. The bacteriologic evaluation was made with Gentry's and Williams' technic. After the irradiation the groups were taken to commercial hatchery and were incubated in satndards conditions. The bacteriologic evaluation of the shell showed a significant 2.8 log reduction on the group of eggs that were irradiated with 1 KGy as compared with 0.5 KGy doses group and control group (P<0.05). A negative correlation (r=-0.93) between irradiation doses and CFU (P<0.05) was also observed. Bacteriologic evaluation of the internal shell membrane exhibited a highly significant inactivation (P<0.01) of S. enteriditis of 100% in the group of eggs irradiated at 2 and 3 kGy. A high negative correlation (r=-0.90) between irradiation doses and samples of internal structures (P<0.05) was observed. The results obtained suggested that the electrons irradiation may be use like a control system of salmonelosis on egg and like desinfection system on hatching eggs because it did not cause any effect on hatchability and broiler performance. (Author)

MicroRNA-276 promotes egg-hatching synchrony by up-regulating brm in locusts

Science.gov (United States)

He, Jing; Chen, Qianquan; Wei, Yuanyuan; Jiang, Feng; Yang, Meiling; Hao, Shuguang; Guo, Xiaojiao; Chen, Dahua; Kang, Le

2016-01-01

Developmental synchrony, the basis of uniform swarming, migration, and sexual maturation, is an important strategy for social animals to adapt to variable environments. However, the molecular mechanisms underlying developmental synchrony are largely unexplored. The migratory locust exhibits polyphenism between gregarious and solitarious individuals, with the former displaying more synchronous sexual maturation and migration than the latter. Here, we found that the egg-hatching time of gregarious locusts was more uniform compared with solitarious locusts and that microRNA-276 (miR-276) was expressed significantly higher in both ovaries and eggs of gregarious locusts than in solitarious locusts. Interestingly, inhibiting miR-276 in gregarious females and overexpressing it in solitarious females, respectively, caused more heterochronic and synchronous hatching of progeny eggs. Moreover, miR-276 directly targeted a transcription coactivator gene, brahma (brm), resulting in its up-regulation. Knockdown of brm not only resulted in asynchronous egg hatching in gregarious locusts but also impaired the miR-276–induced synchronous egg hatching in solitarious locusts. Mechanistically, miR-276 mediated brm activation in a manner that depended on the secondary structure of brm, namely, a stem-loop around the binding site of miR-276. Collectively, our results unravel a mechanism by which miR-276 enhances brm expression to promote developmental synchrony and provide insight into regulation of developmental homeostasis and population sustaining that are closely related to biological synchrony. PMID:26729868

76 FR 32188 - Hatch Solar Energy Center 1, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

Science.gov (United States)

2011-06-03

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER11-3635-000] Hatch Solar Energy Center 1, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for... Hatch Solar Energy Center 1, LLC's application for market-based rate authority, with an accompanying...

Seasonal variations in larval biomass and biochemical composition of brown shrimp, Crangon crangon (Decapoda, Caridea), at hatching

Science.gov (United States)

Urzúa, Ángel; Anger, Klaus

2013-06-01

The "brown shrimp", Crangon crangon (Linnaeus 1758), is a benthic key species in the North Sea ecosystem, supporting an intense commercial fishery. Its reproductive pattern is characterized by a continuous spawning season from mid-winter to early autumn. During this extended period, C. crangon shows significant seasonal variations in egg size and embryonic biomass, which may influence larval quality at hatching. In the present study, we quantified seasonal changes in dry weight (W) and chemical composition (CHN, protein and lipid) of newly hatched larvae of C. crangon. Our data revealed significant variations, with maximum biomass values at the beginning of the hatching season (February-March), a decrease throughout spring (April-May) and a minimum in summer (June-September). While all absolute values of biomass and biochemical constituents per larva showed highly significant differences between months ( P larvae" hatching from larger "winter eggs" showed higher initial values of biomass compared to "summer larvae" originating from smaller "summer eggs". This indicates carry-over effects persisting from the embryonic to the larval phase. Since "winter larvae" are more likely exposed to poor nutritional conditions, intraspecific variability in larval biomass at hatching is interpreted as part of an adaptive reproductive strategy compensating for strong seasonality in plankton production and transitory periods of larval food limitation.

effects of hatching egg weight and length of storage period

African Journals Online (AJOL)

metinpetek

There were no significant effects of egg storage period on body weight and feed ... chicks from all groups were reared under the same growing conditions in battery ... on hatching time, apparent fertility, hatchability of fertile and total eggs data ...

Reproductive behavior and physiology of Dacus oleae: egg hatch in females mated successively with normal and gamma sterilized males and vice versa

International Nuclear Information System (INIS)

Economopoulos, A.P.; Giannakakis, A.; Voyadjoglou, A.V.

1976-01-01

In Dacus oleae (Gmelin), a 2nd mating by an 8-krad gamma ray-sterilized male reduced egg hatch immediately to zero or near-zero in ca. 40-55 percent of individually-tested females. In another 50 percent of females, egg hatch was reduced to between 5 to 70 percent, while in fewer than 10 percent of females, egg hatch showed no change. The above was true for females reared on artificial diet for more than 50 generations and mated with same type males, as well as females reared on olives for 6 to 8 generations and mated first with same type males and 2nd with artificially-reared sterilized males. When the 2nd males were treated at 15 krad the effect on egg hatch was smaller. When the 2nd males were treated at 8 krad and had depleted their sperm, by repeated matings, they produced small or no-effect on egg hatch. When artificially-reared females mated first with a sterilized and second with a normal same type male, egg hatch increased from 0 to 5 percent to 70 to 100 percent in 50 to 55 percent of the cases. In another 43 percent of cases, egg hatch increased to levels between 5 to 70 percent. The combined findings from the 2 mating sequence types are as follows. After females mated first with normal males, egg hatch was above 80 percent in the population; a 2nd mating with 8-krad-sterilized males produced an immediate decrease of egg hatch to ca. 25 percent, decreasing slowly thereafter. When the 1st male was sterilized and the 2nd normal, egg hatch increased to ca. 70 percent, decreasing slowly thereafter

Transferases activity in blood plasma of chickens hatched from eggs irradiated during incubation by low dose gamma rays

International Nuclear Information System (INIS)

Kraljevic, P.; Vilic, M.; Miljanic, S.; Simpraga, M.

2005-01-01

In our earlier studies chickens hatched from eggs irradiated with 0.15 Gy gamma rays before incubation showed a significantly higher growth than controls during the fattening period (1-42 days). The activity of aspartate-aminotransferase (AST), alanine-aminotransferase (ALT) and plasma glucose in the same chickens were also significantly higher. These results suggested that low-dose gamma-radiation stimulated certain metabolic processes in chickens hatched from eggs irradiated before incubation. The goal of this study was to determine the effects of low-dose ionising radiation on AST and ALT activity in the blood plasma of chickens hatched from eggs irradiated during incubation. The eggs of heavy breeding chickens (Avian, line 34) were exposed to 0.15 Gy of gamma-radiation (6 0C o) on the seventh day of incubation, i.e. at the time when the organogenesis in chickens is completed. The control group of chickens hatched from non-irradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 7, 10, 20, 32 and 42. The activity of both enzymes was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. On day 10, AST and ALT activity were significantly higher in the blood plasma of chickens hatched from irradiated eggs, but it significantly dropped for both enzymes on day 20. Our results indicate that exposure of eggs to low-dose gamma-radiation on the seventh day of incubation affects AST and ALT activity in the blood plasma of chickens hatched from irradiated eggs. However, this effect is somewhat different from the effects of egg exposure to low-dose gamma radiation before incubation.(author)

An insight into the heat and mass transfer mechanisms of eggshells hatching broiler chicks and its effects to the hatcher environment.

Science.gov (United States)

Romanini, C E B; Exadaktylos, V; Hong, S W; Tong, Q; McGonnell, I; Demmers, T G M; Bergoug, H; Guinebretière, M; Eterradossi, N; Roulston, N; Verhelst, R; Bahr, C; Berckmans, D

2015-02-01

Thermodynamic study of incubated eggs is an important component in the optimisation of incubation processes. However, research on the interaction of heat and moisture transfer mechanisms in eggs is rather limited and does not focus on the hatching stage of incubation. During hatch, both the recently hatched chick and the broken eggshell add extra heat and moisture contents to the hatcher environment. In this study, we have proposed a novel way to estimate thermodynamically the amount of water evaporated from a broken eggshell during hatch. The hypothesis of this study considers that previously reported drops in eggshell temperature during hatching of chicks is the result remaining water content evaporating from the eggshell, released on the inner membrane by the recently hatched wet chick, just before hatch. To reproduce this process, water was sprayed on eggshells to mimic the water-fluid from the wet body of a chick. For each sample of eggshell, the shell geometry and weight, surface area and eggshell temperature were measured. Water evaporation losses and convection coefficient were calculated using a novel model approach considering the simultaneous heat and mass transfer profiles in an eggshell. The calculated average convective coefficient was 23.9 ± 7.5 W/m(2) °C, similar to previously reported coefficients in literature as a function of 0.5-1m/s air speed range. Comparison between measured and calculated values for the water evaporation showed 68% probability accuracy, associated to the use of an experimentally derived single heat transfer coefficient. The results support our proposed modelling approach of heat and mass transfer mechanisms. Furthermore, by estimating the amount of evaporated water in an eggshell post-hatch, air humidity levels inside the hatcher can be optimised to ensure wet chicks dry properly while not dehydrating early hatching chicks. Copyright © 2014 Elsevier Ltd. All rights reserved.

Production traits of artificially and naturally hatched geese in intensive and free-range systems - II: slaughter, carcass and meat quality traits.

Science.gov (United States)

Boz, M A; Sarıca, M; Yamak, U S

2017-04-01

1. This study investigates the slaughter, carcass and meat quality traits of artificially and naturally hatched geese in intensive and free-range production systems. 2. The study was conducted with 114 naturally hatched and 102 artificially hatched geese. From each replicate of the intensive and free-range systems, one female and one male goose were slaughtered at the ages of 14, 16 and 18 weeks (a total of 32 geese per slaughter week). 3. Artificially hatched geese had higher slaughter weights (5280 vs. 4404 g), carcass weights (3520 vs. 2863), dressing percentages (66.6-65.2% vs. 65.0-63.6%) and carcass part, feather and edible inner organ weights. The ratio of both edible inner organs and abdominal fat was higher in naturally hatched geese. Breast meat L*, a* and pH values and thigh meat dry matter values were higher in artificially hatched geese, whereas thigh meat b* and pH values were higher in naturally hatched geese. 4. Intensively reared geese had higher slaughter weights (4900 vs. 4783 g), carcass weights (3253 vs. 3130 g) and abdominal fat weights (280 vs. 250 g), as well as higher dressing percentages (66.3-64.9% vs. 65.3-63.9%). Breast meat b* and thigh meat L* values were higher in the intensive system, while breast and thigh pH values, dripping loss and cooking loss were higher in the free-range system. Water-holding capacity was higher in the intensive system. 5. In conclusion, artificially hatched, intensively reared geese had the highest slaughter weights; however, both artificially and naturally hatched geese raised in a free-range system reached acceptable slaughter weights and can thus be recommended for use with this type of production system.

Entrainment of the Circadian Rhythm in Egg Hatching of the Crab Dyspanopeus sayi by Chemical Cues from Ovigerous Females.

Science.gov (United States)

Forward, Richard B; Sanchez, Kevin G; Riley, Paul P

2016-02-01

The subtidal crab Dyspanopeus sayi has a circadian rhythm in larval release with a free-running period of 24.1 h. Under constant conditions, eggs hatch primarily in the 4-h interval after the time of sunset. The study tested the new model for entrainment in subtidal crabs, which proposes that the female perceives the environmental cycles and entrains the endogenous rhythm in the embryos. Results verified the model for D. sayi. Hatching by embryos collected from the field when they had not yet developed eye pigments, and were kept in constant conditions attached to their mother, exhibited the circadian hatching rhythm. Attached embryos could also be entrained to a new photoperiod in the laboratory before they developed eye pigments. Further, mature embryos removed from the female hatched rhythmically, indicating that a circadian rhythm resides in the embryos. However, if mature embryos with eye pigments were removed from the female and exposed to a new light-dark cycle, they could not be entrained to the new cycle; rather, they hatched according to the timing of the original light-dark cycle. Nevertheless, detached, mature embryos would entrain to a new light-dark cycle if they were in chemical, but not physical, contact with the female. Thus, the female perceives the light-dark cycle, and uses chemical cues to entrain the circadian rhythm of hatching by the embryos. © 2016 Marine Biological Laboratory.

Analysis of survival and hatching transcriptomes from potato cyst nematodes, Globodera rostochiensis and G. pallida.

Science.gov (United States)

Duceppe, Marc-Olivier; Lafond-Lapalme, Joël; Palomares-Rius, Juan Emilio; Sabeh, Michaël; Blok, Vivian; Moffett, Peter; Mimee, Benjamin

2017-06-20

Potato cyst nematodes (PCNs), Globodera rostochiensis and G. pallida, cause important economic losses. They are hard to manage because of their ability to remain dormant in soil for many years. Although general knowledge about these plant parasitic nematodes has considerably increased over the past decades, very little is known about molecular events involved in cyst dormancy and hatching, two key steps of their development. Here, we have studied the progression of PCN transcriptomes from dry cysts to hatched juveniles using RNA-Seq. We found that several cell detoxification-related genes were highly active in the dry cysts. Many genes linked to an increase of calcium and water uptake were up-regulated during transition from dormancy to hydration. Exposure of hydrated cysts to host plant root exudates resulted in different transcriptional response between species. After 48 h of exposure, G. pallida cysts showed no significant modulation of gene expression while G. rostochiensis had 278 differentially expressed genes. The first G. rostochiensis significantly up-regulated gene was observed after 8 h and was coding for a transmembrane metalloprotease. This enzyme is able to activate/inactivate peptide hormones and could be involved in a cascade of events leading to hatching. Several known effector genes were also up-regulated during hatching.

Effects of Essential Oils and Plant Extracts on Hatching, Migration and Mortality of Meloidogyne incognita

Directory of Open Access Journals (Sweden)

S.K. Ibrahim.

2006-12-01

Full Text Available The nematicidal activity of the essential oil/pure components and plant extracts of naturally grown aromatic plant species against hatching, migration and mortality of the root knot nematode Meloidogyne incognita was investigated. The pure components carvacrol, thymol, and linalool at 1, 2 and 4 mg liter-1 concentrations were the most toxic against M. incognita second-stage juveniles (J2s followed by terpineol and menthone. Hatching was completely inhibited at low concentrations (2, 4 mg liter-1 of carvacrol, thymol, and linalool. Clove extracts (1 mg liter-1 of Allium sativum significantly reduced hatching activity to below 8%, followed by flower extracts of Foeniculum vulgare which reduced hatching to below 25%. These extracts were also toxic against J2s of M. incognita (LC50 43 followed by leaf extracts of Pinus pinea, Origanum syriacum, Mentha microcorphylla, Eucalyptus spp. and Citrus sinensis with an estimated LC50 of 44, 50, 65, 66 and 121 ppm respectively. Flower extracts of F. vulgare had the highest effect on J2 mortality in sand (86%. The highest concentration of essential oils (6% was detected in leaf extracts of Origanium syriacum. Over 30 major components were identified in all the plant extracts tested.

Asynchronous hatching provides females with a means for increasing male care but incurs a cost by reducing offspring fitness.

Science.gov (United States)

Ford, L E; Smiseth, P T

2016-02-01

In species with biparental care, sexual conflict occurs because the benefit of care depends on the total amount of care provided by the two parents while the cost of care depends on each parent's own contribution. Asynchronous hatching may play a role in mediating the resolution of this conflict over parental care. The sexual conflict hypothesis for the evolution of asynchronous hatching suggests that females adjust hatching patterns in order to increase male parental effort relative to female effort. We tested this hypothesis in the burying beetle Nicrophorus vespilloides by setting up experimental broods with three different hatching patterns: synchronous, asynchronous and highly asynchronous broods. As predicted, we found that males provided care for longer in asynchronous broods whereas the opposite was true of females. However, we did not find any benefit to females of reducing their duration of care in terms of increased lifespan or reduced mass loss during breeding. We found substantial negative effects of hatching asynchrony on offspring fitness as larval mass was lower and fewer larvae survived to dispersal in highly asynchronous broods compared to synchronous or asynchronous broods. Our results suggest that, even though females can increase male parental effort by hatching their broods more asynchronously, females pay a substantial cost from doing so in terms of reducing offspring growth and survival. Thus, females should be under selection to produce a hatching pattern that provides the best possible trade-off between the benefits of increased male parental effort and the costs due to reduced offspring fitness. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

ORION - Crew Module Side Hatch: Proof Pressure Test Anomaly Investigation

Science.gov (United States)

Evernden, Brent A.; Guzman, Oscar J.

2018-01-01

The Orion Multi-Purpose Crew Vehicle program was performing a proof pressure test on an engineering development unit (EDU) of the Orion Crew Module Side Hatch (CMSH) assembly. The purpose of the proof test was to demonstrate structural capability, with margin, at 1.5 times the maximum design pressure, before integrating the CMSH to the Orion Crew Module structural test article for subsequent pressure testing. The pressure test was performed at lower pressures of 3 psig, 10 psig and 15.75 psig with no apparent abnormal behavior or leaking. During pressurization to proof pressure of 23.32 psig, a loud 'pop' was heard at 21.3 psig. Upon review into the test cell, it was noted that the hatch had prematurely separated from the proof test fixture, thus immediately ending the test. The proof pressure test was expected be a simple verification but has since evolved into a significant joint failure investigation from both Lockheed Martin and NASA.

Cosmonaut Gidzenko Near Hatch Between Unity and Destiny

Science.gov (United States)

2001-01-01

Cosmonaut Yuri P. Gidzenko, Expedition One Soyuz commander, stands near the hatch leading from the Unity node into the newly-attached Destiny laboratory aboard the International Space Station (ISS). The Node 1, or Unity, serves as a cornecting passageway to Space Station modules. The U.S.-built Unity module was launched aboard the Orbiter Endeavour (STS-88 mission) on December 4, 1998, and connected to Zarya, the Russian-built Functional Cargo Block (FGB). The U.S. Laboratory (Destiny) module is the centerpiece of the ISS, where science experiments will be performed in the near-zero gravity in space. The Destiny Module was launched aboard the Space Shuttle Orbiter Atlantis (STS-98 mission) on February 7, 2001. The aluminum module is 8.5 meters (28 feet) long and 4.3 meters (14 feet) in diameter. The laboratory consists of three cylindrical sections and two endcones with hatches that will be mated to other station components. A 50.9-centimeter- (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations, and payload racks will occupy 13 locations especially designed to support experiments.

Assessing the role of food quality in the production and hatching of Temora longicornis eggs

DEFF Research Database (Denmark)

Jonasdottir, Sigrun; Visser, Andre; Jespersen, C.

2009-01-01

We utilized the varying fatty acid composition of phytoplankton to create 19 different food treatments based on different ratios of 5 potentially important fatty acids and offered these to the copepod Temora longicornis. Egg production and hatching was monitored and related to ingested carbon......, dietary fatty acids and the utilization of maternal fatty acid reserves. Egg production rates depended on ingested carbon and the fatty acid 20:5n-3 from the diet and from the female reserves. Hatching success showed a significant dependence on the ingested and maternal fatty acids 22:6n-3, 18:5n-3 and 18......:3n-3. Production of nauplii as a combination of egg production and hatching was highly dependent on the fatty acid 22:6n-3 and carbon ingestion. The study confirms the importance of n-3 polyunsaturated fatty acids for copepod reproduction and indicates that the female differentially utilizes its...

Maternal manipulation of hatching asynchrony limits sibling cannibalism in the predatory mite Phytoseiulus persimilis.

Science.gov (United States)

Schausberger, P; Hoffmann, D

2008-11-01

1. Sibling cannibalism is a common phenomenon in the animal kingdom but entails a high risk of direct and inclusive fitness loss for the mother and her offspring. Therefore, mechanisms limiting sibling cannibalism are expected to be selected for. One way of maternal manipulation of sibling cannibalism is to influence hatching asynchrony between nearby laid eggs. This has rarely been tested experimentally. 2. We examined the ability of ovipositing females of the cannibalistic predatory mite Phytoseiulus persimilis to influence the occurrence of sibling cannibalism among offspring by manipulating hatching asynchrony of nearby laid eggs. 3. In the first experiment, we assessed the occurrence of sibling cannibalism in relation to the hatching interval (24 h and 48 h) between nearby laid eggs. In the second experiment, we tested whether ovipositing females discriminate sites containing young (24-h old) and old (48-h old) eggs, fresh and old traces (metabolic waste products and possibly pheromones) left by the same female (24 h and 48 h ago), or young eggs plus fresh female traces and old eggs plus old female traces. Both experiments were conducted with and without prey. 4. Without prey, siblings were more likely to cannibalize each other if the hatching interval between nearby laid eggs was short (24 h). Cannibalism occurred less often when senior siblings (protonymphs) experienced a delay in the opportunity to cannibalize junior siblings (larvae). 5. Independent of prey availability, females preferentially added new eggs to sites containing old eggs plus old female traces but did neither distinguish between young and old eggs presented without own traces nor between fresh and old traces presented without eggs. 6. We discuss cue perception and use by P. persimilis females and contrast the outcome of our experiments and theoretical predictions of sibling cannibalism. We conclude that P. persimilis mothers increase hatching asynchrony of nearby laid eggs to prevent

Effect of Some Egg Quality Traits on Hatching Results in Brown Pure Lines

Directory of Open Access Journals (Sweden)

İsmail Durmuş

2016-09-01

Full Text Available This study was conducted to determine the influence of eggshell thickness, albumen height, yolk height and haugh unit on hatching results. A total of 746 eggs, which were obtained and evaluated for egg quality parameters from 100 brown pure line hens of 42 weeks of age, were used. Eggs were collected from each hen for 12 days and individual incubation was carried out. Eggs were grouped based on quality parameters and evaluated accordingly. The findings suggested that hatchability, hatchability of fertile eggs, early, mid and late embryonic mortality did not differ in terms of haugh unit, albumen height, eggshell thickness and yolk height groups. However, early embryonic mortality was found different between the yolk height groups. No relationship was determined among albumen height, haugh unit, eggshell thickness and hatching results. There was no relation between yolk height and hatchability of fertile eggs, hatchability, mid and late embryonic mortalities but was a positive correlation with early embryonic mortality. The results of the present study demonstrate that egg quality parameters studied here had no influence on hatching results except that early embryonic mortality increased with the yolk height.

Evaluation of disinfectants and antiseptics to eliminate bacteria from the surface of turkey eggs and hatch gnotobiotic poults.

Science.gov (United States)

Sylte, M J; Chandra, L C; Looft, T

2017-07-01

Bird eggs are in contact with intestinal microbiota at or after oviposition, but are protected from bacterial translocation by a glycoprotein cuticle layer, the shell, and internal membranes. In a preliminary study, turkey eggs were hatched in a germ-free environment. Firmicutes 16S rRNA gene was detected in the cecal microbiota of hatched poults, suggesting that poults may acquire spore-formers by exposure to shell contents during hatching. Generating gnotobiotic poults for research requires elimination of bacteria from the egg's surface without damaging the developing embryo. The ability of different disinfectants and antiseptics to eliminate eggshell bacteria without harming the developing embryo was tested. Different classes of disinfectants and antiseptics (halogens, biguanidines, and oxidants) were selected to target spores and vegetative bacteria likely present on the egg's surface. Eggs were treated by fully immersing in heated antiseptic (betadine or chlorhexidine) or disinfectant (alkaline bleach, acidified bleach, chlorine dioxide, Oxysept-333, or Virkon S) solutions for up to 15 minutes. Shells were aseptically harvested for aerobic and anaerobic culturing of bacteria. Toxicity to the developing embryo was assessed by gross evaluation of developmental changes in treated eggs incubated up to 27 d of embryonation. Halogen disinfectants acidified bleach and chlorine dioxide, and oxidants Oxysept-333 and Virkon-S eliminated viable bacteria from eggshells. However, addition of oxidants, alone or in combination with other treatments, produced significant (P eliminated viable bacteria from whole turkey eggs, and produced hatched poults in a gnotobiotic isolator. As a control, eggs were treated with PBS, incubated, and hatched under germ-replete conditions. After hatching, poults were euthanized and treated poults had no detectable bacterial growth or 16S rRNA gene qPCR amplification, demonstrating that acidified sodium hypochlorite, chlorine dioxide, and

Hatchery waste: nutritional evaluation of non-hatched eggs.

Science.gov (United States)

de Souza, M L; Jokl, L; da Silva, J M; Vieira, E C

1978-12-01

Hen's non-hatched eggs were processed by boiling for 30 minutes, milling in a meat grinder, and drying at 60 degrees C with continuous ventilation. The product contained 36% of protein, 27% of ether extract, 17% of ash, 10% of calcium, and 0.6% of phosphorus. The quality of the protein was comparable to that of a reference casein and of fresh egg meal, as determined by protein efficiency ratio and apparent net protein utilization.

Bacteria-induced egg hatching differs for Trichuris muris and Trichuris suis

DEFF Research Database (Denmark)

Vejzagic, Nermina; Adelfio, Roberto; Keiser, Jennifer

2015-01-01

BACKGROUND: Eggs of the porcine whipworm Trichuris suis are currently explored in human clinical trials as a treatment of immune-mediated diseases. In this context, only the infective, embryonated eggs, constitute the Active Pharmaceutical Ingredient (API). The rodent whipworm, Trichuris muris...... is commonly used as a laboratory model to study Trichuris biology. The embryonated eggs (containing a fully developed larva) are biologically active and will invade the large intestinal mucosa of the host. This study aims to assess the in vitro hatching of T. muris and T. suis eggs in various bacterial...... cultures as a measure for their biological activity. METHODS: Eggs of T. muris and T. suis were incubated with Escherichia coli strain (BL-21) at three concentrations in a slightly modified in vitro egg hatching assay previously developed for T. muris. Additionally, E. coli strains (M15, SG13009, PMC103...

Effect of cryopreservation on the pre-hatching behavior in the Mexican fruit fly Anastrepha ludens Loew (Diptera, Tephritidae).

Science.gov (United States)

Rajamohan, Arun; Rinehart, Joseph P; Leopold, Roger A

2018-02-01

In a sampling of untreated embryos of the economically important fruit pest species, Anastrepha ludens, the cumulative hatch percentage in the lab was noted to be ∼85%. Approximately 70% of the larvae had eclosed through the posterior pole of the egg. This process is effected by the act of Pole Reversal (PR) of the fully developed pre-hatch larva from the wider anterior to the narrower posterior pole of the egg. Investigation of the effects of cryopreservation and various pretreatments prior to cryostorage on the PR behavior was prompted by the observation of significantly lower proportion of cryopreserved embryos exhibiting the PR behavior. Pretreatments (dechorionation and permeabilization) followed by vitrification resulted in delayed hatching, reflecting a slower embryonic development rate of ∼10 h. A smaller proportion of the treated embryos either eclosed from the anterior end of the egg or did not eclose at all despite complete development and prehatch gnawing activity. In the untreated controls, 24.0% of the embryos eclosed from the anterior pole. After permeabilization and cryopreservation, 83% and 55% (adjusted hatch) of the embryos were noted to hatch this way, respectively. An analysis of the hatch count after the treatments shows that factors contributing to the embryos' inability to properly invert polarity is not solely due to cryopreservation but also due to the pretreatment procedures including dechorionation and permeabilization. In fact, the permeabilization pre-treatment contributed the highest to this phenomenon lending support to the view that chemical toxicity rather than physical effects of cryopreservation play a major role in post-cryopreservation effects. Published by Elsevier Inc.

Fertilisation and hatching success of Atlantic cod (Gadus morhua) eggs when exposed to various concentrations of produced water

International Nuclear Information System (INIS)

Wong, D.; Lyons, M.; Burridge, L.; Lee, K.

2010-01-01

This study investigated the fertilization and hatching success of Atlantic cod (Gadus morhua) eggs that were exposed to various dilutions of produced water from a natural gas production platform. A control group of eggs was fertilized in sea water without any produced water. Another set of eggs were fertilized in sea water with 4 different concentrations of produced water and held their respective concentrations for 24 hours to evaluate the success of the fertilization. Viable fertilized eggs were transferred to 96 well plates containing fresh sea water and incubated in the dark at approximately 6 degrees C until hatch. Eggs began hatching about 14 days after fertilization (DPF), peaked at about 17 DPF, then finished hatching by 21 DPF. Analysis of PAH content in the diluted produced water showed that at 0.32 percent, 1.08 percent and 3.6 percent concentrations, the fertilization success was greater than or equal to that of the control group. However, for the 12 percent concentration, there were no viable fertilized eggs present after the 24 hour period. Survivability of eggs during sea water incubation was similar for the 0 percent, 0.32 percent and 1.08 percent treatment groups, but egg mortality increased for the 3.60 percent concentration group, to about 61.5 percent mean cumulative mortality at 6 DPF, then remained constant. The mean hatching success for all dilutions was presented.

A Short History of the Hatching Enzyme Studies in Medaka(Development of Medaka Biology in Japan-Part II)

OpenAIRE

Yamagami, Kenjiro

1997-01-01

The studies on the hatching enzyme of the medaka, Oryzias latipes, have a history of about 50 years, which is only a half of whole history of the studies on the hatching enzyme in animals since the first conjecture of it in a lung fish in 1900. Medaka, however, has served as the material most intensively studied for the enzyme, and the studies have given invaluable information to establish some significant concepts in the field of developmental and cell biology as well as the hatching biology...

Garlic essential oil increases rates of eggs fertilization and hatching of Rhamdia quelen larvae in an artificial incubation system

Directory of Open Access Journals (Sweden)

Nilton Garcia Marengoni

Full Text Available ABSTRACT: The objective of this study was to evaluate the effects of garlic (Allium sativum essential oil on the rates of eggs fertilization and hatching and on the normal development of larvae of artificially incubated silver catfish (Rhamdia quelen. The experiment was carried out using a completely randomized experimental design with four treatments and five replicates. The treatments consisted of introducing garlic essential oil into the incubators, which used a closed system of water recirculation, at concentrations of 0, 1, 3, and 5mg L-1. Rates of eggs fertilization and larval hatching were determined at 10 and 24h after the beginning of eggs hydration. Morphology of larvae was assessed with the aid of a stereo microscope to determine the rate of normal development. The concentration of 5mg L-1 promoted better rates of eggs fertilization and larval hatching. Concentrations of garlic essential oil had a linear effect on eggs fertilization rates and larval hatching. Garlic oil did not influence the morphology of the larvae (P>0.05. It is recommended to use 5mg L-1 of garlic essential oil to promote better rates of eggs fertilization and larval hatching of artificially incubated silver catfish.

Effect of temperature and salinity on egg hatching and description of the life cycle of Lernanthropus latis (Copepoda: Lernanthropidae) infecting barramundi, Lates calcarifer.

Science.gov (United States)

Brazenor, Alexander K; Hutson, Kate S

2013-10-01

The parasite Lernanthropus latis (Copepoda: Lernanthropidae) is a major threat to the sustained mariculture of barramundi, Lates calcarifer (Perciformes: Latidae). We investigated the effect of water temperature and salinity on egg hatching success of L. latis and describe the life cycle for the first time. Wild and sea-caged L. calcarifer examined in tropical north Australia exhibited similar parasite prevalence (range: 80-100%) and mean parasite intensity (range: 3-6), whereas land-based maricultured fish were not infected. Hatching success and time to first and last hatch was determined for a range of water temperature (22, 30, 32 and 34°C) and salinity (0, 11, 22, 35 and 40‰) combinations representing current and predicted climate conditions. There was a significant interaction between water temperature and salinity on the hatching success of L. latis nauplii. Eggs hatched in all temperature treatments, with the greatest hatching success at 30°C and 32°C (98 and 92% success, respectively) in 35‰. Hatching did not occur at 0‰ and was severely reduced at 11‰ (1.6% success). Hatching began within 6h at all water temperatures with >95% of eggs hatched within 30h at 30, 32 and 34°C and within 60h at 22°C. Adult parasites differed from the original description by the presence of the parabasal flagellum, small setae on the legs and caudal rami and minor incongruences regarding morphological measurements. The life cycle of L. latis includes three free living stages and five parasitic stages. Although L. latis exhibits broad environmental tolerance, freshwater can be used as an effective management strategy to break the life cycle in aquaculture. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

9 CFR 94.6 - Carcasses, parts or products of carcasses, and eggs (other than hatching eggs) of poultry, game...

Science.gov (United States)

2010-01-01

... carcasses, and eggs (other than hatching eggs) of poultry, game birds, or other birds; importations from..., DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS... § 94.6 Carcasses, parts or products of carcasses, and eggs (other than hatching eggs) of poultry, game...

Effect of temperature on incubation period, embryonic mortality, hatch rate, egg water loss and partridge chick weight (Rhynchotus rufescens

Directory of Open Access Journals (Sweden)

Nakage ES

2003-01-01

Full Text Available The aim of this study was to determine the effects of incubation temperature (34.5; 35.5; 36.5; 37.5 and 38.5ºC, on incubation period, embryonic mortality, hatching rate, water loss and chick weight at hatch, using daily incubation of partridge (Rhynchotus rufescens eggs. The highest hatching percentage was obtained between 35.5 and 36.5ºC. Incubation length and temperature were inversely proportional. Water loss was lower in eggs incubated at low temperatures as compared to high temperatures. There was no difference among incubation temperatures in absolute and relative hatchling weights. Early embryonic mortality increased at low temperatures (36.5ºC. Our results show that, under conditions of daily incubation of eggs in the same incubator, higher hatching rate can be obtained using temperatures between 35.5ºC and 36.5ºC; incubation temperature is inversely proportional to incubation length, and absolute and relative weights of partridge chicks are not affected by incubation temperature.

Hatching system and time effects on broiler physiology and posthatch growth

NARCIS (Netherlands)

Ven, van de L.J.F.; Wagenberg, van A.V.; Debonne, M.; Decuypere, E.; Kemp, B.; Brand, van den H.

2011-01-01

A multilevel housing system for broilers was developed, named Patio (Vencomatic BV, Eersel, the Netherlands), in which the hatching and brooding phase are combined. In a Patio system, climate conditions differ from those provided in the hatchers currently in use. We compared the physiology of

Unity hatch closed in preparation for launch on STS-88

Science.gov (United States)

1998-01-01

Workers in the Space Station Processing Facility close the access hatch to the Unity connecting module, part of the International Space Station, before its launch aboard Space Shuttle Endeavour on STS-88 in December. Unity will now undergo a series of leak checks before a final purge of clean, dry air inside the module to ready it for initial operations in space. Other testing includes the common berthing mechanism to which other space station elements will dock and the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter. The next time the hatch will be opened it will be by astronauts on orbit. Unity is expected to be ready for installation into the payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27. The Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time.

The radiological evaluation of a prototype posting-in hatch under conditions of high alpha activity

International Nuclear Information System (INIS)

Smith, D.I.; Hollick, R.C.

1987-07-01

A prototype posting-in hatch, mounted vertically in the top panel of a highly active glovebox has been radiologically evaluated in the Fuels Laboratory, AEEW. This simple, air-lock type system of 100 mm diameter has pneumatically operated and interlocked lids and a low velocity, inward purge, supplied by the glovebox depression. The hatch proved extremely reliable and very easy to operate. More than 1200 simulated posting movements were carried out and a > 8 order of magnitude reduction in aerosol concentration was recorded from the active glovebox to the monitoring environment. (author)

Falcon Nest Occupancy and Hatch Success Near Two Diamond Mines in the Southern Arctic, Northwest Territories

Directory of Open Access Journals (Sweden)

Daniel W. Coulton

2013-12-01

Full Text Available Sensitivity to anthropogenic disturbance in conjunction with slow population recovery has raised conservation concerns over impacts to raptor species from industrial development in pristine areas of their North American breeding range. We evaluated whether the presence of two diamond mines resulted in negative effects to nest use and hatch success of breeding falcons in the southern Arctic barren-grounds of the Northwest Territories. A total of 20 nest sites of Peregrine Falcon (Falco peregrinus and Gyrfalcon (Falco rusticolus breeding within 26 km of the Diavik and Ekati diamond mines were monitored annually during 1998 to 2010. The objective of the study was to test the effects of distance from mines, relative nest age, rainfall, small mammal abundance, and mine activity levels on nest occupancy and hatch rates. Model selection results indicated that nests that were older were more likely and consistently used than nests that were established more recently. A decrease in nest use associated with the mines was not detected. Hatch success was best explained by a positive association with distance from development and a negative trend over the study period, however, these effects were weak. Hatch success of nests within and beyond an estimated 5.9 km distance threshold was similar, and for nest sites within this distance was unrelated to annual changes in accumulated mine footprint area through time. Hatch success for nest sites near Diavik was unrelated to changes in this mine's activity through time. Although natural and anthropogenic effects were generally weak, the lines of evidence suggested that the observed patterns were more likely the result of natural factors operating at a regional scale than more localized effects from the activity of two diamond mines.

Effect of cadmium, lead and arsenic on the oviposition, hatching and embryonic survival of Biomphalaria glabrata

International Nuclear Information System (INIS)

Ansaldo, Martin; Nahabedian, Daniel E.; Di Fonzo, Carla; Wider, Eva A.

2009-01-01

Biomphalaria glabrata is a widespread freshwater gastropod mollusc. The easy aquaculture of these organisms allow its use as an accessible tool for contamination bioassays. B. glabrata showed marked metabolic responses when exposed to cadmium, lead and arsenic. Those responses could also affect the reproduction of the snails. Taking into account this hypothesis, B. glabrata were exposed for 96 h (acute laboratory bioassays) to different concentrations of cadmium (0.1, 0.05 and 0 mg/L), lead (0.5, 0.1, 0.05 and 0 mg/L) and arsenic (0.5, 0.1, 0.05 and 0 mg/L). Snails were removed from the aquaria while eggs were left in the same contaminant concentrations. The effect of the assayed toxicants on snail reproduction was registered as the alterations of the total number of laid eggs (TNLE), hatching time and embryonic survival. At 0.10 mg/L cadmium significantly decreased the TNLE (p < 0.05) and no embryos survived. The lowest assayed level (0.05 mg/L) of cadmium, delayed the hatching time twice when it was compared with the control group (p < 0.01). Lead decreased the TNLE at 0.5 mg/L level (p < 0.01). The other assayed doses (0.05 and 0.10 mg/L) also decreased embryonic survival significantly (p < 0.05 and p < 0.01 respectively) and extended twice the time to hatching (p < 0.01). The 0.50 mg/L level killed all embryos. Arsenic at all studied concentrations decreased the TNLE (p < 0.05) while the hatching time was increased by 50%. Embryo survival only decreased at the highest level (0.5 mg/L) of arsenic assayed. In summary, the acute exposure (96 h) to cadmium lead and arsenic, altered the reproduction of B. glabrata, modifying the TNLE, hatching time and embryonic survival

Hatching rate and growth rate of Nothobranchius guentheri fertilized eggs after space flight

International Nuclear Information System (INIS)

Guo Mingzhong; Zheng Leyun; Lin Guangji; Zhong Jianxing; Yang Huosheng; Zheng Yangfu

2012-01-01

Hatching, abnormal, growth and survival rate of the fertilized eggs of Nothobranchius guentheri were carried by Shenzhou 7 spacecraft were studied. The results indicated that the hatching and abnormal rate were no significant difference between the spaceflight group (99.3% and 16.8%) and ground group (97.2% and 10.4%); but the growth rate of male fish from spaceflight group was significant higher (0.094 g/d) than that of ground group (0.059 g/d), leading to the significant bigger of the male fish from spaceflight group. The survival rate of spaceflight group (66.7%) was higher than the ground group (47.9%). It was concluded that there was a higher growth and survival rate of Nothobranchius guentheri fertilized eggs after space flight. (authors)

Interannual differences in growth and hatch-date distributions of early juvenile European anchovy in the Bay of Biscay: implications for recruitment

KAUST Repository

Aldanondo, Naroa; Cotano, Unai; Goikoetxea, Nerea; Boyra, Guillermo; Ibaibarriaga, Leire; Irigoien, Xabier

2016-01-01

trajectories and hatch-date distributions were inferred over a 3-year period based on otolith microstructure analysis. Otolith growth trajectories showed a characteristic shape depending on their hatch-date timing. Earlier-born juveniles had notably broader

Microscopic morphology and apoptosis of ovarian tissue after cryopreservation using a vitrification method in post-hatching turkey poults, Meleagris gallopavo

Science.gov (United States)

1. Microscopic morphology of ovarian tissue in post-hatching turkey poults at various ages was investigated. 2. Hematoxylin and eosin staining were used and the diameter of the oocytes and follicles were measured using microphotography. 3. Immediately after hatching, oocytes in one-day turkey pou...

Interannual differences in growth and hatch-date distributions of early juvenile European anchovy in the Bay of Biscay: implications for recruitment

KAUST Repository

Aldanondo, Naroa

2016-01-22

© 2016 John Wiley & Sons Ltd. In order to understand better the recruitment variability in European anchovy in the Bay of Biscay, it is important to investigate the processes that affect survival during the early life stages. Anchovy juvenile growth trajectories and hatch-date distributions were inferred over a 3-year period based on otolith microstructure analysis. Otolith growth trajectories showed a characteristic shape depending on their hatch-date timing. Earlier-born juveniles had notably broader maximum increments than later born conspecifics, resulting in higher growth rates. This observation suggests that early hatching would be beneficial for larval and juvenile growth, and, therefore, survival. The estimated juvenile hatch-date distributions were relatively narrow compared with the extended anchovy spawning season (March-August) in the Bay of Biscay and indicated that only individuals originated mainly from the summer months (June-August) survived until autumn. Hatch-date distributions were markedly different among years and seemed to influence the interannual recruitment strength of anchovy. We conclude that years characterized by juvenile survivors originating from the peak spawning period (May and June) would lead to considerable recruitment success. Downwelling events during the peak spawning period seem to affect larval survival.

Concentration of total proteins in blood plasma of chickens hatched from irradiated eggs with low dose gamma radiation

International Nuclear Information System (INIS)

Vilic, M.; Kraljevic, P.; Miljanic, S.; Simpraga, M.

2005-01-01

It is known that low-dose ionising radiation may have stimulating effects on chickens. Low doses may also cause changes in the concentration of blood plasma total proteins, glucose and cholesterol in chickens. This study investigates the effects of low dose gamma-radiation on the concentration of total proteins in the blood plasma of chickens hatched from eggs irradiated with a dose of 0.15 Gy on incubation days 7 and 19. Results were compared with the control group (chickens hatched from non-irradiated eggs). After hatching, all other conditions were the same for both groups. Blood samples were drawn from the heart, and later from the wing vein on days 1, 3, 5, 7,10, 20, 30 and 42. The concentration of total proteins was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 7 showed a statistically significant decrease on the sampling day 3 (P less than 0.05) and 7 (P less than 0.01). The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 19 showed a statistically significant increase only on sampling day 1 (P less than 0.05). These results suggest that exposure of eggs to 0.15 Gy of gamma-radiation on the 7th and 19th day of incubation could produce different effects on the protein metabolism in chickens.(author)

Concentration of Proteins and Protein Fractions in Blood Plasma of Chickens Hatched from Eggs Irradiated with Low Level Gamma Rays

International Nuclear Information System (INIS)

Kraljevic, P.; Vilic, M.; Simpraga, M.; Matisic, D.; Miljanic, S.

2011-01-01

In literature there are many results which have shown that low dose radiation can stimulate many physiological processes of living organism. In our earlier paper it was shown that low dose of gamma radiation has a stimulative effect upon metabolic process in chickens hatched from eggs irradiated before incubation. This was proved by increase of body weight gain and body weight, as well as by increase of two enzymes activities in blood plasma (aspartate aminotransferase and alanine aminotransferase) which play an important role in protein metabolism. Therefore, an attempt was made to determine the effect of eggs irradiation by low dose gamma rays upon concentration of total proteins and protein fractions in the blood plasma of chickens hatched from irradiated eggs. The eggs of heavy breed chickens were irradiated with a dose of 0.15 Gy gamma radiation (60Co) before incubation. Along with the chickens which were hatched from irradiated eggs, there was a control group of chickens hatched from nonirradiated eggs. All other conditions were the same for both groups of chickens. Blood samples were taken from the right jugular vein on the 1 s t and 3 r d day, or from the wing vein on days 5 and 7 after hatching. The total proteins concentration in the blood plasma was determined by the biuret method using Boehringer Mannheim GmbH optimized kits. The protein fractions (albumin, α 1 -globulin, α 2 -globulin, β- and γ-globulins) were estimated electrophoretically on Cellogel strips. The total proteins concentration was significantly decreased in blood plasma of chickens hatched from irradiated eggs on days 3 (P t h day (P 2 -globulin was decreased on days 1 (P t h day of life. Obtained results indicate that low dose of gamma radiation has mostly inhibitory effect upon concentration of total proteins and protein fractions in the blood plasma of chickens hatched from irradiated eggs before incubation. (author)

R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes

Energy Technology Data Exchange (ETDEWEB)

Infante Ferreira, C A; Nan, X [Delft University of Technology (Netherlands). Laboratory for Refrigeration and Indoor Climate Control; Newell, T A; Chato, J C [University of Illinois, Urbana, IL (United States). Dept. of Mechanical and Industrial Engineering

2003-06-01

Two-phase heat transfer coefficient characteristics of R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes are experimentally investigated. Experimental parameters include a lubricating polyol ester oil concentration varied from 0 to 4%. The test runs were done at average inlet saturated condensing temperatures of 40{sup o}C. The inlet vapor was kept at saturation (quality = 1.0). The mass fluxes were between 200 and 600 kg/m{sup 2}s, and the heat fluxes were selected to obtain a quality of 0.0 at the outlet of the test section, varying from 5 to 45 kW/m{sup 2}. The heat transfer enhancement factor varied between 1.8 and 2.4 for both microfin and cross-hatched tubes. The larger values applied for larger mass fluxes for the cross-hatched tube and smaller mass fluxes for the microfin tube. Enhancement factors increased as oil concentration increased up to oil concentrations of 2%. For higher oil concentrations the enhancement decreased especially at high mass fluxes, the cross-hatched tube being less sensitive to oil contamination. Pressure drop in the test section increased by approximately 25% as the oil concentration increased from 0 to 4%. The results from the experiments are compared with those calculated from correlations reported in the literature. Moreover, modified correlations for the condensation heat transfer coefficient are proposed for practical applications. (author)

Enterobacteriaceae and Salmonella recovered from non-sanitized and sanitized broiler hatching eggs

Science.gov (United States)

Sanitizing hatching eggs may reduce the chances that a flock will become colonized with Salmonella and reduce the numbers of other microorganisms, such as Enterobacteriaceae, that can depress hatchability. An experiment was conducted to determine if a quaternary-biguanide sanitizer applied as foam ...

Effect of Formalin on the Hatching Rate of eggs and Survival of ...

African Journals Online (AJOL)

Michael Horsfall

1, and 1000 mgl-1 of formalin resulted in total egg mortality (0% hatching rate). In the definitive ... treatment of fish disease, particularly fungi, as in this study, where it effectively reduced fungi on eggs and larvae of ... salmon held for spawning).

The effect of gamma irradiation on fertile eggs and hatched chick performance

International Nuclear Information System (INIS)

Mekkawy, S.H.

1995-01-01

Two handier fertile white arber acers eggs were exposed to gamma irradiation (Co 6 0) at the following levels 0, 100, 150 and 200 rad. They Were then hatched with the control eggs and hatchability, growth rate, feed consumption, feed conversion, carcass quality, carcass analysis and the blood analysis were determined. Hatchability was reduced gradually with increased radiation, but significantly, no differences in body weight between irradiated and control chicks were apparent at hatching time. At the end of the experimental 45 days, the mean heavight was that of the irradiation dose of 150 rad. The feed conversion efficiency was enhanced by the irradiation treatments, especially with the dose of 200 rad. There were no differences in the carcass quality and carcass composition between the treated and non-treated birds. The results demonstrated that, the irradiation treatments had no effects on the blood analysis of the birds. 7 tabs

Long term exposure to low dose neurotoxic pesticides affects hatching, viability and cholinesterase activity of Artemia sp.

Science.gov (United States)

Gambardella, Chiara; Nichino, Daniela; Iacometti, Camillo; Ferrando, Sara; Falugi, Carla; Faimali, Marco

2018-03-01

The brine shrimp Artemia was used as a model organism to test toxicity of several neuroactive pesticides (chlorpyrifos (CLP), chlorpyrifos oxon (CLP ox), diazinon (DZN), carbaryl (CBR)) following exposure to far below than lethal doses. Cysts were exposed to the pesticides in order to test a scenario similar to actual coastal environment contamination, by analyzing different responses. Cysts were rehydrated in water containing the pesticides at concentrations ranging from 10 -11 to 10 -5  M, for 72, 96 and 192 h, respectively. For these exposure times, morpho-functional and biochemical parameters, such as hatching speed and viability were investigated in the larvae together with cholinesterase (ChE) activity quantification and histochemical localization. Finally, ChE inhibition was also compared with conventional selective ChE inhibitors. Results showed that CLP ox and CBR caused a significant dose-dependent decrease in hatching speed, followed by high percentages of larval death, while CLP and DZN were responsible for irregular hatching patterns. In addition, the pesticides mostly caused larval death some days post-hatching, whereas this effect was negligible for the specific ChE inhibitors, suggesting that part of pesticide toxicity may be due to molecules other than the primary target. ChE activity was observed in the protocerebrum lobes, linked to the development of pair eyes. Such activity was inhibited in larvae exposed to all pesticides. When compared to conventional selective inhibitors of ChE activities, this inhibition demonstrated that the selected pesticides mainly affect acetylcholinesterase and, to a lesser extent, pseudocholinesterases. In conclusion, the brine shrimp is a good model to test the environmental toxicity of long term exposure to cholinergic pesticides, since changes in hatching speed, viability and ChE activity were observed. Copyright © 2018 Elsevier B.V. All rights reserved.

Pre- and post-hatch trophic egg production in the subsocial burrower bug, Canthophorus niveimarginatus (Heteroptera: Cydnidae)

Science.gov (United States)

Filippi, Lisa; Baba, Narumi; Inadomi, Koichi; Yanagi, Takao; Hironaka, Mantaro; Nomakuchi, Shintaro

2009-02-01

In recent years, three terrestrial bugs, Adomerus triguttulus and Sehirus cinctus (Cydnidae) and the closely related Parastrachia japonensis (Parastrachiidae), have been the focus of several fascinating studies because of the remarkable, extensive parental care they were found to display. This care includes egg and nymph guarding, production of trophic eggs, unfertilized, low cost eggs that are used as food by newly hatched nymphs, and progressive provisioning of the host seed. In this study, we have investigated yet a third related Asian cydnid, Canthophorus niveimarginatus, with regard to the possible occurrence of some or all of these complex traits in order to assess how widespread these maternal investment patterns are in this group of insects and to better understand the implications of their manifestations from an evolutionary context. Manipulative experiments were carried out in the lab to determine whether females provision nests. Observational and egg removal studies were carried out to determine whether trophic eggs are produced, and, if they are, their possible impact on nymphal success. The findings revealed that C. niveimarginatus does, in fact, progressively provision young, and this species also displays all of the other behaviors associated with extended parental care in subsocial insects. Moreover, unlike the other two related species, which place trophic eggs on the surface of the original egg mass, C. niveimarginatus produces both pre- and post-hatch trophic eggs. Nymphs deprived of access to post-hatch trophic eggs had significantly lower body weight and survival rate than those that fed on them. To our knowledge, this is the first time the production of both pre- and post-hatch trophic eggs has been demonstrated in insects outside the Hymenoptera. In this paper, we qualitatively and quantitatively demonstrate the provisioning behavior and patterns of trophic egg production in C. niveimarginatus. When and how trophic eggs are produced and

Periodical low eggshell temperatures during incubation and post hatch dietary arginine supplementation

NARCIS (Netherlands)

Afsarian, O.; Shahir, M.H.; Akhlaghi, A.; Lotfolahian, H.; Hoseini, A.; Lourens, A.

2016-01-01

An experiment was conducted to evaluate the effects of a periodically low eggshell temperature exposure during incubation and dietary supplementation of arginine on performance, ascites incidence, and cold tolerance acquisition in broilers. A total of 2,400 hatching eggs were randomly assigned to

Spawning and hatching of endangered Gila Chub in captivity

Science.gov (United States)

Schultz, Andrew A.; Bonar, Scott A.

2016-01-01

Information on reproductive characteristics of the endangered Gila Chub Gila intermedia is largely limited and qualitative, and culture techniques and requirements are virtually unknown. Here we provide the first published data on spawning and selected reproductive and developmental characteristics of Gila Chub. Fish were brought to the laboratory in March 2003 from Sabino Creek, Arizona (12.3°C). Fish were then warmed slowly and spawned at 14.9°C, 10 d after collection. Following this initial spawning, Gila Chub spawned consistently in the laboratory without hormonal, chemical, photoperiod, temperature, or substrate manipulation during all times of the year. Spawns were noted at temperatures ranging from about 15°C to 26°C; however, we noted that Gila Chub spawned less frequently at temperatures above 24°C. Multiple spawning attempts per year per individual are probable. There was a strong, inverse relationship between time to hatch and incubation temperature. The hatch rate of eggs was high (mean = 99.43%), and larval Gila Chub accepted a variety of natural and formulated diets at first feeding. The future of Gila Chub may someday depend in part on hatchery propagation to provide specimens for restocking formerly occupied habitats and establishing refuge populations. Information from our study can aid future efforts to successfully spawn and rear Gila Chub and related species.

Chemical characteristics and thickness of Podocnemis expansa post-hatching eggshells (Testudines, Podocnemididae

Directory of Open Access Journals (Sweden)

Caio Henrique Ferreira

2016-10-01

Full Text Available Knowledge on chemical components of the post-hatching eggshell of reptiles may provide indicators of the quality of the diet offered to females kept in captivity. Therefore, the objective of this study was to investigate the chemical characteristics of the calcareous layer, as well as the thickness of Podocnemis expansa post-hatching eggshells. Eggshell thickness was 183±1.405 µm. This value is similar to that of the eggs of other Testudines with flexible eggshells. As for the chemical composition, the following percentages were observed: nitrogen 7.983 ± 0.054; crude protein 49.91 ± 0.324; crude fat 0.068 ± 0.002; mineral matter 20.302 ± 0.807; calcium 13.374 ± 0.647; and phosphorus 0.176 ± 0.003. Knowledge on chemical composition of the eggshell may aid the nutrition of P. expansa raised in commercial facilities, once this species is an alternative and promising source of exotic meat.

Phenology of three coexisting annual fish species: seasonal patterns in hatching dates

Czech Academy of Sciences Publication Activity Database

García, D.; Loureiro, M.; Machín, E.; Reichard, Martin

2018-01-01

Roč. 809, č. 1 (2018), s. 323-337 ISSN 0018-8158 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : Birth date * Climate change * Hatching synchrony * Intraguild predation * Killifish * Otoliths Subject RIV: EG - Zoology Impact factor: 2.056, year: 2016

Dietary Chlorella supplementation effect on immune responses and growth performances of broiler chickens exposed to post hatch holding time

DEFF Research Database (Denmark)

Sugiharto, S; Lauridsen, Charlotte

2016-01-01

The study was carried out to investigate the effect of dietary Chlorella sp. supplementation on immune response and growth performance of broiler chickens exposed to post hatch holding time. Allotted in 36 pens, a total of 180 newly hatched chicks were assigned in a 3 × 2 factorial design, with d...

Edwin I. Hatch Nuclear Plant, Unit 2. License application, general information

International Nuclear Information System (INIS)

1975-01-01

An application for a direct cycle BWR is presented. The reactor will be located about 11 miles north of Baxley, Ga., near the south bank of the Ultamaha River in Appling County close to Hatch-1 Reactor. The core thermal power level will be 2537 MW(t) and the electrical power level will be 795 MW(e). Mechanical cooling towers will be utilized

Effects of transgenic sterilization constructs and their repressor compounds on hatch, developmental rate and early survival of electroporated channel catfish embryos and fry.

Science.gov (United States)

Su, Baofeng; Shang, Mei; Li, Chao; Perera, Dayan A; Pinkert, Carl A; Irwin, Michael H; Peatman, Eric; Grewe, Peter; Patil, Jawahar G; Dunham, Rex A

2015-04-01

Channel catfish (Ictalurus punctatus) embryos were electroporated with sterilization constructs targeting primordial germ cell proteins or with buffer. Some embryos then were treated with repressor compounds, cadmium chloride, copper sulfate, sodium chloride or doxycycline, to prevent expression of the transgene constructs. Promoters included channel catfish nanos and vasa, salmon transferrin (TF), modified yeast Saccharomyces cerevisiae copper transport protein (MCTR) and zebrafish racemase (RM). Knock-down systems were the Tet-off (nanos and vasa constructs), MCTR, RM and TF systems. Knock-down genes included shRNAi targeting 5' nanos (N1), 3' nanos (N2) or dead end (DND), or double-stranded nanos RNA (dsRNA) for overexpression of nanos mRNA. These constructs previously were demonstrated to knock down nanos, vasa and dead end, with the repressors having variable success. Exogenous DNA affected percentage hatch (% hatch), as all 14 constructs, except for the TF dsRNA, TF N1 (T), RM DND (C), vasa DND (C), vasa N1 (C) and vasa N2 (C), had lower % hatch than the control electroporated with buffer. The MCTR and RM DND (T) constructs resulted in delayed hatch, and the vasa and nanos constructs had minimal effects on time of hatch (P nanos constructs, doxycycline greatly delayed hatch (P < 0.05). Adverse effects of the transgenes and repressors continued for several treatments for the first 6 days after hatch, but only in a few treatments during the next 10 days. Repressors and gene expression impacted the yield of putative transgenic channel catfish fry, and need to be considered and accounted for in the hatchery phase of producing transgenically sterilized catfish fry and their fertile counterparts. This fry output should be considered to ensure that sufficient numbers of transgenic fish are produced for future applications and for defining repressor systems that are the most successful.

Heart Rate Responses to Unaided Orion Side Hatch Egress in the Neutral Buoyancy Laboratory

Science.gov (United States)

English, Kirk L.; Hwang Emma Y.; Ryder, Jeffrey W.; Kelly, Cody; Walker, Thomas; Ploutz-Snyder, Lori L.

2016-01-01

NASA is developing the Orion capsule as a vehicle for transporting crewmembers to and from the International Space Station (ISS) and for future human space exploration missions. Orion and other commercial vehicles are designed to splash down in the ocean where nominally support personnel will assist crewmembers in egressing the vehicle. However, off-nominal scenarios will require crewmembers to egress the vehicle unaided, deploy survival equipment, and ingress a life raft. PURPOSE: To determine the heart rate (HR) responses to unaided Orion side hatch egress and raft ingress as a part of the NASA Crew Survival Engineering Team's evaluation of the PORT Orion mockup in the Neutral Buoyancy Laboratory (NBL). METHODS: Nineteen test subjects, including four astronauts (N=19, 14 males/5 females, 38.6+/-8.4 y, 174.4+/-9.6 cm, 75.7+/-13.1 kg), completed a graded maximal test on a cycle ergometer to determine VO2peak and HRpeak and were divided into five crews of four members each; one subject served on two crews. Each crew was required to deploy a life raft, egress the Orion vehicle from the side hatch, and ingress the life raft with two 8 kg emergency packs per crew. Each crew performed this activity one to three times; a total of ten full egresses were completed. Subjects wore a suit that was similar in form, mass, and function to the Modified Advanced Crew Escape Suit (MACES) including helmet, gloves, boots, supplemental O2 bottles, and a CO2-inflated life preserver (approx.18 kg); subjects began each trial seated supine in the PORT Orion mockup with seat belts and mockup O2 and communication connections and ended each trial with all four crewmembers inside the life raft. RESULTS: VO2peak was 40.8+/-6.8 mL/kg/min (3.1+/-0.7 L/min); HRpeak was 181+/-10 bpm. Total egress time across trials was 5.0+/-1.6 min (range: 2.8-8.0 min); all subjects were able to successfully complete all trials. Average maximum HR at activity start, at the hatch opening, in the water, and in the

Control of egg hatch ability and adult emergence of three fruit fly species in papayas by gamma irradiation

International Nuclear Information System (INIS)

Resilva, S.S.; Pasion, W.B.; Moy, J.H.

1991-01-01

The effects of gamma radiation on the oriental fruit fly, Bactrocera Dorsalis (Hendel), melon fly, Bactrocera Cucurbitae (Coquilett), and Mediterranean fruit fly, Ceratitis Capitata (Weidemann) were studied. Melon fly was determined to be the most susceptible of the three species. A dosage of 550 Gy rendered the eggs 100% sterile when irradiated in papayas at 4-6 hours before hatching. Oriental and mediterranean fruit flies were found to be more resistant, requiring doses of 750 and 850 Gy, respectively. A dose of only 100 Gy was needed to inhibit adult eclosion when the three species were treated at third instar larvae. Warm water treatment at 49 0 C for 20 minutes was found sufficient in preventing the hatching of any egg in the infested papaya fruits. However, since eggs may hatch before the warm-water treatment can be applied, a combination of irradiation treatment using 100 Gy is recommended for disinfestation of papaya fruits. (author). 17 refs.; 3 tabs

Association between land cover and Culicoides (Diptera: Ceratopogonidae) breeding sites on four Danish cattle farms

DEFF Research Database (Denmark)

Kirkeby, Carsten; Bødker, Rene; Stockmarr, Anders

2009-01-01

from 30 sampling points. Soil samples were set up in emergence chambers for hatching adult Culicoides. Two species of Culicoides (C punctatus and C pulicaris) emerged from nine of 12 soil samples from a wet, grazed field with manure. Seventy-two other samples from similar land cover on the three other......Biting midges of the genus Culicoides are vectors of bluetongue virus. Their larval habitats are poorly known in Northern Europe. Three classes of the CORINE land cover index, found within 300 in of four farms in Denmark, were used to stratify sampling sites for a total of 360 soil core samples...... farms were negative. Seven sampling points from pastures were incorrectly classified by CORINE. The remaining 23 sampling points were classified correctly. The visually observed land use was not sufficiently detailed to adequately predict Culicoides breeding sites in this study. The CORINE index failed...

Combined Effects of Egg Age and Gamma Radiation Dosage on egg hatch of Scolytus Amygdali/guer

International Nuclear Information System (INIS)

Tadros, A.W.; Abdallah, F.F.; Abdelsalam, K.A.; Hashem, A.G.

1992-01-01

Eggs of Scolytus Amygdali were irradiated with 5 to 300 gray of gamma radiation at a dose rate of 7.87 rad/second. One-to five-day-old eggs were used. Results showed that one-and-tow-day-old eggs were the most sensitive as 100% mortality were obtained at 40 and 50 gray, respectively. Three-day-old-eggs required 100 gray to prevent hatch ability; while 300 gray were needed to prevent the 4-and 5-day-old eggs from hatching. There was 7.2-fold increase in resistance as eggs matured from 1 to 5 days measured by dosages required to produce LD 50. 2 fig

Development of the generic drug industry in the US after the Hatch-Waxman Act of 1984

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Garth Boehm

2013-09-01

Full Text Available The key events in the development of the US generic drug industry after the Hatch-Waxman Act of 1984 are systematically reviewed, including the process of approval for generic drugs, bioequivalence issues including “switchability”, bioequivalence for complicated dosage forms, patent extension, generic drug safety, generic substitution and low-cost generics. The backlog in generic review, generic drug user fees, and “quality by design” for generic drugs is also discussed. The evolution of the US generic drug industry after the Hatch-Waxman Act in 1984 has afforded several lessons of great benefit to other countries wishing to establish or re-establish a domestic generic drug industry.

Embryo malposition as a potential mechanism for mercury-induced hatching failure in bird eggs

Science.gov (United States)

Herring, G.; Ackerman, Joshua T.; Eagles-Smith, Collin A.

2010-01-01

We examined the prevalence of embryo malpositions and deformities in relation to total mercury (THg) and selenium (Se) concentrations in American avocet (Recurvirostra americana), black-necked stilt (Himantopus mexicanus), and Forster's tern (Sterna forsteri) eggs in San Francisco Bay (CA, USA) during 2005 to 2007. Overall, 11% of embryos were malpositioned in eggs ???18 d of age (n=282) and 2% of embryos were deformed in eggs ???13 d of age (n=470). Considering only those eggs that failed to hatch (n=62), malpositions occurred in 24% of eggs ???18 d of age and deformities occurred in 7% of eggs ???13 d of age. The probability of an embryo being malpositioned increased with egg THg concentrations in Forster's terns, but not in avocets or stilts. The probability of embryo deformity was not related to egg THg concentrations in any species. Using a reduced dataset with both Se and THg concentrations measured in eggs (n=87), we found no interaction between Se and THg on the probability of an embryo being malpositioned or deformed. Results of the present study indicate that embryo malpositions were prevalent in waterbird eggs that failed to hatch and the likelihood of an embryo being malpositioned increased with egg THg concentrations in Forster's terns. We hypothesize that malpositioning of avian embryos may be one reason for mercury-related hatching failure that occurs late in incubation, but further research is needed to elucidate this potential mechanism. ?? 2010 SETAC.

Hatching success in salamanders and chorus frogs at two sites in Colorado, USA: Effects of acidic deposition and climate

Science.gov (United States)

Muths, E.; Campbell, D.H.; Corn, P.S.

2003-01-01

The snowpack in the vicinity of the Mount Zirkel Wilderness Area is among the most acidic in the western United States. We analyzed water chemistry and examined hatching success in tiger salamanders and chorus frogs at ponds there and at nearby Rabbit Ears Pass (Dumont) to determine whether acid deposition affects amphibians or their breeding habitats at these potentially sensitive locations. We found a wide range of acid neutralizing capacity among ponds within sites; the minimum pH recorded during the experiment was 5.4 at one of 12 ponds with all others at pH ??? 5.7. At Dumont, hatching success for chorus frogs was greater in ponds with low acid neutralizing capacity; however, lowest pHs were >5.8. At current levels of acid deposition, weather and pond characteristics are likely more important than acidity in influencing hatching success in amphibian larvae at these sites.

Impact of egg disinfection of hatching eggs on the eggshell microbiome and bacterial load

DEFF Research Database (Denmark)

Olsen, R.; Kudirkiene, E.; Thofner, I.

2017-01-01

Disinfection of hatching eggs is essential to ensure high quality production of broilers. Different protocols are followed in different hatcheries; however, only limited scientific evidence on how the disinfection procedures impact the microbiome is available. The aim of the present study...... was to characterize the microbiome and aerobic bacterial load of hatching eggs before disinfection and during the subsequent disinfection steps. The study included a group of visibly clean and a group of visibly dirty eggs. For dirty eggs, an initial wash in chlorine was performed, hereafter all eggs were submitted...... to two times fumigation and finally spray disinfection. The eggshell microbiome was characterized by sequencing of the total amount of 16S rRNA extracted from each sample, consisting of shell surface swabs of five eggs from the same group. In addition, the number of colony forming units (cfu) under...

Notes on the hatching phases and the size of the juveniles in the Snake-eyed skink Ablepharus kitaibelii (Bibron & Bory de Saint-Vincent, 1833)

Science.gov (United States)

Vergilov, Vladislav; Natchev, Nikolay

2018-03-01

Most of the studies dealing with the Snake-eyed skink (Ablepharus kitaibelii) treat predominantly aspects of the distribution and taxonomy of the species. In the present study we provide information concerning the mechanism of hatching in the Snake-eyed skink and the dimensions of the hatched specimens. We collected data from wild animals, as well as from indoor incubated juveniles. The present study provides the first data concerning the weight of the newly hatched juveniles of the species and discuss on potential misleading data concerning the size of the juveniles in A. kitaibelii.

Hatching response to temperature along a latitudinal gradient by the fairy shrimp Branchinecta lindahli (Crustacea; Branchiopoda; Anostraca in culture conditions

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D. Christopher Rogers

2014-08-01

Full Text Available Branchinecta lindahli is a broadly distributed fairy shrimp, reported from a range of temporary wetland habitat types in arid western North America. This species’ eggs hatch after the habitat dries, refills from seasonal rain, and receives a strong cold shock during the winter low temperatures. I studied phenotypic variation in temperature responses in cultures collected from four populations across 8° of latitude with low average temperatures ranging from -8 to 8°C. Time to maturation, mature body size and first clutch size decreased, as temperature increased, with only minor body size variability at mortality, regardless of culture origin. No variation in individual egg size was observed, demonstrating that body size is sacrificed to produce at least a few normal eggs during unfavourable years. Latitudinal variation in hatching temperature demonstrated a pattern of adaptive significance, with some overlap between regional temperature hatching cues.  Phenotypic hatching temperature and growth rate responses may cause genetic segregation, selecting one cohort for warmer, dryer years and one cohort for cooler, wetter years.  Drier year selected cohorts can exploit habitats that have shorter hydroperiods even in wet years. This may lead to population specialisation and speciation by adapting to more extreme habitats

Conservation of the egg envelope digestion mechanism of hatching enzyme in euteleostean fishes.

Science.gov (United States)

Kawaguchi, Mari; Yasumasu, Shigeki; Shimizu, Akio; Sano, Kaori; Iuchi, Ichiro; Nishida, Mutsumi

2010-12-01

We purified two hatching enzymes, namely high choriolytic enzyme (HCE; EC 3.4.24.67) and low choriolytic enzyme (LCE; EC 3.4.24.66), from the hatching liquid of Fundulus heteroclitus, which were named Fundulus HCE (FHCE) and Fundulus LCE (FLCE). FHCE swelled the inner layer of egg envelope, and FLCE completely digested the FHCE-swollen envelope. In addition, we cloned three Fundulus cDNAs orthologous to cDNAs for the medaka precursors of egg envelope subunit proteins (i.e. choriogenins H, H minor and L) from the female liver. Cleavage sites of FHCE and FLCE on egg envelope subunit proteins were determined by comparing the N-terminal amino acid sequences of digests with the sequences deduced from the cDNAs for egg envelope subunit proteins. FHCE and FLCE cleaved different sites of the subunit proteins. FHCE efficiently cleaved the Pro-X-Y repeat regions into tripeptides to dodecapeptides to swell the envelope, whereas FLCE cleaved the inside of the zona pellucida domain, the core structure of egg envelope subunit protein, to completely digest the FHCE-swollen envelope. A comparison showed that the positions of hatching enzyme cleavage sites on egg envelope subunit proteins were strictly conserved between Fundulus and medaka. Finally, we extended such a comparison to three other euteleosts (i.e. three-spined stickleback, spotted halibut and rainbow trout) and found that the egg envelope digestion mechanism was well conserved among them. During evolution, the egg envelope digestion by HCE and LCE orthologs was established in the lineage of euteleosts, and the mechanism is suggested to be conserved. © 2010 The Authors Journal compilation © 2010 FEBS.

Effect of Low Dose Gamma Radiation Upon Phosphatase Activity in Blood Plasma of Chicken Hatched from Eggs Irradiated on the Seventh Day of Incubation

International Nuclear Information System (INIS)

Kraljevic, P.; Vilic, M.; Miljanic, S.; Simpraga, M.

2008-01-01

In our earlier studies chickens hatched from eggs irradiated with 0.15 Gy gamma rays before incubation showed a significantly higher growth than controls during the fattening period (1-42 days). The activity of aspartate-aminotransferase (AST), alanine-aminotransferase (ALT), acid phosphatase (ACP) and plasma glucose in the same chickens were also significantly higher. These results suggested that low-dose gamma-radiation stimulated certain metabolic processes in chickens hatched from eggs irradiated before incubation. Investigating the effect of low dose gamma radiation upon transferases activity in blood plasma of chickens hatched from eggs irradiated on the 7th day of incubation, i.e. in the time when organogenesis is completely finished, we found that on day 10, AST and ALT activity was significantly higher in the blood plasma of those chickens, whereas it significantly dropped for both enzymes on day 20. This time the goal of study was to determine the effect of low-dose gamma radiation on ACP and alkaline phosphatase (ALP) activity in the blood plasma of chickens hatched from eggs irradiated on the 7th day of incubation. The eggs of heavy breeding chickens (Avian, line 34) were exposed to 0.15 Gy of gamma radiation (60Co) on the seventh day of incubation. The control group included chickens hatched from non-irradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 7, 10, 20, 32 and 42. The activity of both enzymes was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. ACP activity was significantly lower in the blood plasma of chickens hatched from irradiated eggs on day 3 (P<0,01), 5 (P<0,05) and 10 (P<0,05). Throughout the experimental period ALP activity did not statistically significantly change. Our results indicate that exposure of eggs to low-dose gamma radiation on the seventh day of incubation reduces ACP activity in the blood plasma

Nervous system disruption and concomitant behavioral abnormality in early hatched pufferfish larvae exposed to heavy oil.

Science.gov (United States)

Kawaguchi, Masahumi; Sugahara, Yuki; Watanabe, Tomoe; Irie, Kouta; Ishida, Minoru; Kurokawa, Daisuke; Kitamura, Shin-Ichi; Takata, Hiromi; Handoh, Itsuki C; Nakayama, Kei; Murakami, Yasunori

2011-08-01

Spills of heavy oil (HO) over the oceans have been proven to have an adverse effect on marine life. It has been hypothesized that exposure of early larvae of sinking eggs to HO leads largely to normal morphology, whereas abnormal organization of the developing neural scaffold is likely to be found. HO-induced disruption of the nervous system, which controls animal behavior, may in turn cause abnormalities in the swimming behavior of hatched larvae. To clarify the toxicological effects of HO, we performed exposure experiments and morphological and behavioral analyses in pufferfish (Takifugu rubripes) larvae. Fertilized eggs of pufferfish were exposed to 50 mg/L of HO for 8 days and transferred to fresh seawater before hatching. The hatched larvae were observed for their swimming behavior, morphological appearance, and construction of muscles and nervous system. In HO-exposed larvae, we did not detect any anomaly of body morphology. However, they showed an abnormal swimming pattern and disorganized midbrain, a higher center controlling movement. Our results suggest that HO-exposed fishes suffer developmental disorder of the brain that triggers an abnormal swimming behavior and that HO may be selectively toxic to the brain and cause physical disability throughout the life span of these fishes.

Effects of Injected Methylmercury on the Hatching of Common Loon (Gavia immer) Eggs

Science.gov (United States)

To determine the level of in ovo methylmercury (MeHg) exposure that results in detrimental effects on fitness and survival of loon embryos and hatched chicks, we conducted a field study in which we injected eggs with various doses of MeHg on day 4 of incubation. Eggs were collect...

Screening of non-tuber bearing Solanaceae for resistance to and induction of juvenile hatch of potato cyst nematodes and their potential for trap cropping

NARCIS (Netherlands)

Scholte, K.

2000-01-01

Ninety accessions of non-tuber bearing Solanaceae were screened for (i) resistance to and (ii) stimulatory effect on juvenile hatch of potato cyst nematodes, and (iii) their growth under temperate climatic conditions. All plant species belonging to the genus Solanum tested induced hatching but this

Olive Ridley Sea Turtle Hatching Success as a Function of Microbial Abundance and the Microenvironment of In Situ Nest Sand at Ostional, Costa Rica

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Vanessa S. Bézy

2014-01-01

Full Text Available Sea turtle hatching success at mass nesting beaches is typically lower than at solitary nesting beaches, presumably due in part to high rates of microbial metabolism resulting from the large input of organic matter from turtle eggs. Therefore, we tested the hypothesis that hatching success varies across areas of the beach in conjunction with differences in the physical nest environment and microbial abundance of in situ olive ridley sea turtle nests at Ostional, Costa Rica. We marked natural nests in high-density, low-density, and tidal-wash nesting areas of the beach and monitored clutch pO2 and temperature throughout the incubation period. We quantified hatching success and collected samples of nest sand during nest excavations. We quantified microbial abundance (bacteria and fungi with a quantitative polymerase chain reaction (qPCR analysis. Hatching success was lower in nests with lower pO2, higher temperatures, higher organic matter content, and higher microbial abundance. Our results suggest that the lower oxygen within the nest environment is likely a result of the high microbial abundance and rates of decomposition in the nest sand and that these factors, along with increased temperature of clutches in the high-density nesting area, are collectively responsible for the low hatching success at Ostional.

Assessing the prevalence of Salmonella enterica in poultry hatcheries by using hatched eggshell membranes.

Science.gov (United States)

Chao, M-R; Hsien, C-H; Yeh, C-M; Chou, S-J; Chu, C; Su, Y-C; Yu, C-Y

2007-08-01

Salmonella enterica causes a number of significant poultry diseases and is also a major pathogen in humans. Most poultry infected by Salmonella become carriers; infection may also be fatal, depending on the particular serovar and the age of the bird at infection. Younger birds are more susceptible to infection by Salmonella, so it is critical that hatcheries monitor birds. We developed a method to use hatched eggshell membranes (HEM) to assess contamination by Salmonella in poultry hatching cabinets and to evaluate the prevalence of Salmonella in a goose hatchery and rearing farm. Comparison of the Salmonella isolation rate in hatching cabinets using 3 sampling methods showed that the highest Salmonella contamination was detected in HEM, and that these results differed significantly from those obtained from fluff samples and cabinet swab samples (P chicken, and duck hatcheries. The lowest Salmonella-positive rate was found for the chicken hatchery, followed by the goose and the duck hatcheries (P hatcheries: A, B, C1, C2, D, and E. The distribution of these serogroups differed among the hatcheries. Salmonella serogroup C1 was the major serogroup found in geese, compared with serogroup B in chickens and ducks. However, Salmonella Typhimurium was dominant in 1 goose hatchery and also in geese from this hatchery that had been transferred to a farm. Antibiotic susceptibility analysis showed that Salmonella Typhimurium strains isolated from the farm geese with diarrhea showed significantly higher resistance to doxycycline, colistin, sulfamethoxazole-trimethoprin, and cephalothin than those isolated from the hatchery (P hatcheries and rearing farms.

Physiological responses of newly hatched broiler chicks to increasing journey distance during road transportation

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Heshmatollah Khosravinia

2015-09-01

Full Text Available This study was conducted to examine the effects on weight loss (WL, residual yolk (RY utilization and serum biochemical parameters of transport distance (TD in newly hatched broiler chicks. Just after hatching, 200 Ross 308 broiler chicks were traveled over 1000 km. At hatchery and after 200, 400, 600, 800 and 1000 km journey, a random sample of 20 birds were killed for blood collection, WL and yolk weight assessment. Live weight decreased linearly by 0.42 and 0.48 g per 100 km of journey in males and female chicks, respectively. Yolk sac residual utilized by 0.071 and 0.069 g per 100 km of travel in males and females chicks, respectively, over journey distances up to 800 km. Extended journey from 800 to 1000 km caused a great decline of 0.51 and 0.58 g per 100 km in yolk weight in male and female chicks, respectively. Serum Ca concentration reduced in TDs up to 400 km, then increased for longer journeys (P<0.05. Over 1000 km journey, serum GLU level of 196.24 mg/dL at hatchery was decreased to 117.31 mg/dL at the end of journey. Serum urea, uric acid and cholesterol concentrations were increased with the extended TDs (P<0.05. In conclusion increasing transportation distance causes intensified physiological stress in broiler chicks with varying effect on different stress indicators. Stress indicators in newly hatched chicks in transit may differ from those proposed for replaced chicks and the broiler chicken at later ages.

Selection for high levamisole resistance in Haemonchus contortus monitored with an egg-hatch assay

NARCIS (Netherlands)

Hoekstra, R.; Borgsteede, F.H.M.; Boersema, J.H.; Roos, M.H.

1997-01-01

To investigate the characteristics of selection for levamisole resistance in Haemonchus contortus, the consecutive nematode generations of an in vivo selection were monitored with a newly developed egg-hatch assay. The in vivo selection was started with a population not previously exposed to any

Larval morphology of Hoplias lacerdae Miranda Ribeiro, 1908 (Characiformes, Erythrinidae, from hatching to metamorphosis, related to exogenous food capture ability

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Cláudia Maria Reis Raposo Maciel

2009-09-01

Full Text Available For the accomplishment of this work, 510 specimens of Hoplias lacerdae were used from one to 30 days after hatching, with the objective of studying the mesoscopic morphological characteristics that enable this species, in the initial phases of its development, to present adaptations for movement and the capture of exogenous food. The yolk sac larvae at 11 days after hatching have the potentiality to capture exogenous food, i.e. prey, even before the total yolk absorption which happens at 12 days, presenting in this phase: an open mouth at one day after hatching, displaying the terminal position at four days; notochord flexion, that takes place at seven days and provides greater efficiency of movement; pectoral fins, also developed at seven days, which facilitate its balance and direction in the water column; formation of the dorsal and anal fins at eight days and the pelvic ones, at 11 days.

Hatching time and alevin growth prior to the onset of exogenous feeding in farmed, wild and hybrid Norwegian Atlantic salmon.

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Monica Favnebøe Solberg

Full Text Available The onset of exogenous feeding, when juveniles emerge from the gravel, is a critical event for salmonids where early emergence and large size provide a competitive advantage in the wild. Studying 131 farmed, hybrid and wild Norwegian Atlantic salmon families, originating from four wild populations and two commercial strains, we investigated whether approximately 10 generations of selection for faster growth has also resulted in increased somatic growth prior to the onset of exogenous feeding. In addition, we tested whether relaxed selection in farms has allowed for alterations in hatching time between farmed and wild salmon. Across three cohorts, wild salmon families hatched earlier than farmed salmon families, while hybrid families displayed intermediate hatching times. While the observed differences were small, i.e., 1-15 degree-days (0-3 days, as water temperatures were c. 5-6°C, these data suggest additive genetic variation for hatching time. Alevin length prior to exogenous feeding was positively related to egg size. After removal of egg size effects, no systematic differences in alevin length were observed between the wild and farmed salmon families. While these results indicate additive genetic variation for egg development timing, and wild salmon families consistently hatched earlier than farmed salmon families, these differences were so small they are unlikely to significantly influence early life history competition of farmed and wild salmon in the natural environment. This is especially the case given that the timing of spawning among females can vary by several weeks in some rivers. The general lack of difference in size between farmed and wild alevins, strongly suggest that the documented differences in somatic growth rate between wild and farmed Norwegian Atlantic salmon under hatchery conditions are first detectable after the onset of exogenous feeding.

The first hop: Use of Beaufort Sea deltas by hatch-year semipalmated sandpipers

Science.gov (United States)

Churchwell, Roy T.; Kendall, Steve J.; Brown, Stephen C.; Blanchard, Arny L.; Hollmen, Tuula E.; Powell, Abby

2018-01-01

River deltas along Alaska’s Beaufort Sea coast are used by hatch-year semipalmated sandpipers (Calidris pusilla) after leaving their terrestrial natal sites, but the drivers of their use of these stopover sites on the first “hop” of fall migration are unknown. We quantified sandpiper temporal distribution and abundance as related to food resources at three river deltas during the beginning of their fall migration (post-breeding period) to compare the habitat quality among these deltas. We conducted population counts, sampled invertebrates, and captured birds to collect blood samples from individuals for triglyceride and stable isotope analyses to determine fattening rates and diet. Patterns of sandpiper and invertebrate abundance were complex and varied among deltas and within seasons. River deltas were used by sandpipers from late July to late August, and peak sandpiper counts ranged from 1000 to 4000 individuals, of which 98% were hatch-year semipalmated sandpipers. Isotopic signatures from blood plasma samples indicated that birds switched from a diet of upland tundra to delta invertebrate taxa as the migration season progressed, suggesting a dependence on delta invertebrates. Despite differences in diet among deltas, we found no differences in fattening rates of juvenile sandpipers as indicated by triglyceride levels. The number of sandpipers was positively associated with abundance of Amphipoda and Oligochaeta at the Jago and Okpilak-Hulahula deltas; an isotopic mixing model indicated that sandpipers consumed Amphipoda and Oligochaeta at Jago, mostly Chironomidae at Okpilak-Hulahula and Spionidae at Canning. Regardless of the difference in sandpiper diets at the Beaufort Sea deltas, their similar fattening rates throughout the season indicate that all of these stopover sites provide a critical food resource for hatch-year sandpipers beginning their first migration.

Morphometry study on pre and post-hatching nerve cell bodies of lumbar spinal ganglia of Gallus domesticus

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Claudio A. Ferraz de Carvalho

1983-09-01

Full Text Available A cytomorphometric study was performed in lumbar spinal ganglia neurons of Gallus domesticus on the 10th and 18th incubation days and 8th, 35th, 61st, and 120th post-hatching days. The absolute volume of nucleus and relative volume of cytoplasm were respectively estimated by the Bach² caryometric method and by point-counting volumetry, carried out in 0.5mm thick araldite sections. The relative volume, the surface-to-volume ratio and the total surface of RER, SER, mitochondria, dense bodies, Golgi complex and the relative volume of hyaloplasm inside and outside the Nissl bodies were estimated from electronmicrographs by the Weibel et al.58 method. The conclusions were: a there was an increase of the cell volume and a decrease of the nucleo-cytoplasmic ratio, particularly between the first two ages; b the relative volumes of RER and SER change inversely with respect to each other: the RER increases before hatching, decreasing progressively afterwards; the changes of relative volume of dense bodies are similar to those of the RER, and the mitochondria show relatively small variations concerning the same parameter; c the relative volume of hyaloplasm inside the Nissl bodies decreases while those outside increases; d the surface-to-volume ratio drops sharply for all organelles from the 10th to the 18th day of incubation; after hatching, a tendency to increase is observed; e the membrane surface-to-cytoplasmic volume ratio decreases for all organelles from the 10th to the 18th day of incubation; after hatching, this ratio increases slightly for mitochondria and Golgi complex, sharply for SER, dropping for dense bodies. The RER values alternate regularly.

Tributyltin induces premature hatching and reduces locomotor activity in zebrafish (Danio rerio) embryos/larvae at environmentally relevant levels.

Science.gov (United States)

Liang, Xuefang; Souders, Christopher L; Zhang, Jiliang; Martyniuk, Christopher J

2017-12-01

Tributyltin (TBT) is an organotin compound that is the active ingredient of many biocides and antifouling agents. In addition to its well established role as an endocrine disruptor, TBT is also associated with adverse effects on the nervous system and behavior. In this study, zebrafish (Danio rerio) embryos were exposed to environmentally relevant concentrations of TBT (0.01, 0.1, 1 nM) to determine how low levels affected development and behavior. Fish exposed to 1 nM TBT hatched earlier when compared to controls. Following a 96-h exposure, total swimming distance, velocity, and activity of zebrafish larvae were reduced compared to controls. To identify putative mechanisms for these altered endpoints, we assessed embryo bioenergetics and gene expression. We reasoned that the accelerated hatch time could be related to ATP production and energy, thus embryos were exposed to TBT for 24 and 48-h exposure prior to hatch. There were no differences among groups for endpoints related to bioenergetics (i.e. basal, ATP-dependent, and maximal respiration). To address mechanisms related to changes in behavioral activity, we measured transcripts associated with muscle function (myf6, myoD, and myoG) and dopamine signaling (th, dat, dopamine receptors) as dopamine regulates behavior. No transcript was altered in expression by TBT in larvae, suggesting that other mechanisms exist that may explain changes in higher level endpoints. These results suggest that endpoints related to the whole animal (i.e. timing of hatch and locomotor behavior) are more sensitive to environmentally-relevant concentrations of TBT compared to the molecular and metabolic endpoints examined here. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ixodes pacificus Ticks Maintain Embryogenesis and Egg Hatching after Antibiotic Treatment of Rickettsia Endosymbiont

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Kurlovs, Andre H.; Li, Jinze; Cheng, Du; Zhong, Jianmin

2014-01-01

Rickettsia is a genus of intracellular bacteria that causes a variety of diseases in humans and other mammals and associates with a diverse group of arthropods. Although Rickettsia appears to be common in ticks, most Rickettsia-tick relationships remain generally uncharacterized. The most intimate of these associations is Rickettsia species phylotype G021, a maternally and transstadially transmitted endosymbiont that resides in 100% of I. pacificus in California. We investigated the effects of this Rickettsia phylotype on I. pacificus reproductive fitness using selective antibiotic treatment. Ciprofloxacin was 10-fold more effective than tetracycline in eliminating Rickettsia from I. pacificus, and quantitative PCR results showed that eggs from the ciprofloxacin-treated ticks contained an average of 0.02 Rickettsia per egg cell as opposed to the average of 0.2 in the tetracycline-treated ticks. Ampicillin did not significantly affect the number of Rickettsia per tick cell in adults or eggs compared to the water-injected control ticks. We found no relationship between tick embryogenesis and rickettsial density in engorged I. pacificus females. Tetracycline treatment significantly delayed oviposition of I. pacificus ticks, but the antibiotic’s effect was unlikely related to Rickettsia. We also demonstrated that Rickettsia-free eggs could successfully develop into larvae without any significant decrease in hatching compared to eggs containing Rickettsia. No significant differences in the incubation period, egg hatching rate, and the number of larvae were found between any of the antibiotic-treated groups and the water-injected tick control. We concluded that Rickettsia species phylotype G021 does not have an apparent effect on embryogenesis, oviposition, and egg hatching of I. pacificus. PMID:25105893

Aridity promotes bet hedging via delayed hatching: a case study with two temporary pond crustaceans along a latitudinal gradient.

Science.gov (United States)

Pinceel, Tom; Vanschoenwinkel, Bram; Hawinkel, Wouter; Tuytens, Karen; Brendonck, Luc

2017-05-01

Climate change does affect not only average rainfall and temperature but also their variation, which can reduce the predictability of suitable conditions for growth and reproduction. This situation is problematic for inhabitants of temporary waters whose reproductive success depends on rainfall and evaporation that determine the length of the aquatic phase. For organisms with long-lived dormant life stages, bet hedging models suggest that a fraction of these should stay dormant during each growing season to buffer against the probability of total reproductive failure in variable environments. Thus far, however, little empirical evidence supports this prediction in aquatic organisms. We study geographic variation in delayed hatching of dormant eggs in natural populations of two crustaceans, Branchinella longirostris and Paralimnadia badia, that occur in temporary rock pools along a 725 km latitudinal aridity gradient in Western Australia. Consistent with bet hedging theory, populations of both species were characterised by delayed hatching under common garden conditions and hatching fractions decreased towards the drier end of the gradient where the probability of reproductive success was shown to be lower. This decrease was most pronounced in the species with the longer maturation time, presumably because it is more sensitive to the higher prevalence of short inundations. Overall, these findings illustrate that regional variation in climate can be reflected in differential investment in bet hedging and hints at a higher importance of delayed hatching to persist when the climate becomes harsher. Such strategies could become exceedingly relevant as determinants of vulnerability under climate change.

Artificial incubation of muscovy duck eggs : Why some eggs hatch and others do not

NARCIS (Netherlands)

Harun, MAS; Veeneklaas, RJ; Visser, GH; Van Kampen, M

This study was designed to gain insight into the influence of spraying and cooling, during artificial incubation, on the embryo metabolic rate and hatching ability of Muscovy duck eggs. Three times a week 93 incubated eggs were sprayed and cooled for 0.5 h at room temperature. Daily embryo metabolic

Anthelminthic activity of methanol extracts of Diospyros anisandra and Petiveria alliacea on cyathostomin (Nematoda: Cyathostominae) larval development and egg hatching.

Science.gov (United States)

Flota-Burgos, G J; Rosado-Aguilar, J A; Rodríguez-Vivas, R I; Arjona-Cambranes, K A

2017-12-15

Methanol extracts of plant structures are promising alternatives to traditional pharmaceutical anthelminthic treatments. An in vitro evaluation was done of how methanol extracts of Diospyros anisandra bark and leaves, and Petiveria alliacea stems and leaves, collected during the rainy and dry seasons, effected cyathostomin larval development and egg hatching. Seven concentrations (600, 300, 150, 75, 37.5, 18.7 and 9.3μg/ml) were tested using the egg hatch assay. An ANOVA was applied to identify differences between the concentrations and the controls. Fifty percent lethal concentration (LC 50 ) and the 95% confidence interval were calculated with a probit analysis. At and above 37.5μg/ml, the D. anisandra bark extracts from both seasons exhibited ≥95% egg hatch inhibition (EHI), while the D. anisandra leaf extracts had >90% EHI at and above 75μg/ml. For P. alliacea, the extracts from leaves and stems from either season exhibited >97% EHI at and above 300μg/ml, although similar efficacy was also observed at lower concentrations with the rainy season stems (75μg/ml) and leaves (150μg/ml). Values for LC 50 were lowest for the rainy season D. anisandra bark (10.2μg/ml) and leaf extracts (18.4μg/ml), followed by the rainy season P. alliacea stems extract (28.2μg/ml). In the D. anisandra extracts, EHI was largely due to its ovicidal activity (≥96% beginning at 37.5μg/ml), whereas in the P. alliacea extracts it was due to L 1 larval hatch failure (≥90% beginning at 75μg/ml). Overall, the rainy season D. anisandra bark extracts had a strong in vitro anthelminthic effect against cyathostomins by inhibiting larval development, and the rainy season P. alliacea stem extracts had a strong effect by preventing egg hatching. Both are possible control alternatives for these nematodes. Copyright © 2017 Elsevier B.V. All rights reserved.

Sexual differences in post-hatching Saunders's gulls: size, locomotor activity, and foraging skill.

Science.gov (United States)

Yoon, Jongmin; Lee, Seung-Hee; Joo, Eun-Jin; Na, Ki-Jeong; Park, Shi-Ryong

2013-04-01

Various selection pressures induce the degree and direction of sexual size dimorphism in animals. Selection favors either larger males for contests over mates or resources, or smaller males are favored for maneuverability; whereas larger females are favored for higher fecundity, or smaller females for earlier maturation for reproduction. In the genus of Larus (seagulls), adult males are generally known to be larger in size than adult females. However, the ontogeny of sexual size dimorphism is not well understood, compared to that in adults. The present study investigates the ontogeny of sexual size dimorphism in Saunders's gulls (Larus saundersi) in captivity. We artificially incubated fresh eggs collected in Incheon, South Korea, and measured body size, locomotor activity, and foraging skill in post-hatching chicks in captivity. Our results indicated that the sexual differences in size and locomotor activity occurred with the post-hatching development. Also, larger males exhibited greater foraging skills for food acquisition than smaller females at 200 days of age. Future studies should assess how the adaptive significance of the sexual size dimorphism in juveniles is linked with sexual divergence in survival rates, intrasexual contests, or parental effort in sexes.

Effects of γ-rays on hatching of the eggs and survival period of the fry of Cyprinus carpio

International Nuclear Information System (INIS)

Shrivastava, R.S.; Dwivedi, P.

1980-01-01

Eggs of the common carp, Cyprinus carpio, were exposed to 0.0258, 0.129, 0.258, 0.516, and 1.29 C/kg, respectively, 60 Co γ-radiation. The time between spawning and hatching of the fry was 48 to 56 hours compared to 72 to 79 hours in the untreated controls. With increasing exposure the hatching rates were 36, 24, 28, 30 and 34%; the survival periods were 11, 9, 8, 7 and 6 days and the 50% mortality period was 8, 7, 6, 4 and 4 days, respectively. With increasing radiation doses the fry exhibited increasing deformations of the body, especially of the postanal region, as well as unbalanced movements

Fly ash effect on hatching, mortality and penetration of root-knot nematode (Meloidogyne incognita in pumpkin roots

Directory of Open Access Journals (Sweden)

Gufran Ahmad

2016-09-01

Full Text Available An experiment was conducted to observe the effect of fly ash on hatching, mortality and penetration of root-knot nematode (Meloidogyne incognita in pumpkin roots. For hatching experiment different fly ash-extract concentrations (5, 10, 20, 30, 40, and 50% were prepared. Hatching was significantly reduced in all concentrations, maximum being at 50% concentration. The mortality (% of juveniles was observed in 1, 2, 3, 4, 5, 6 and 7th days with different levels (5, 10, 20, 30, 40 and 50 % of fly ash-extract. All the levels were found harmful to juveniles. As the level was increased, the killing percentage of juveniles was also increased. Highest mortality was observed in 7th day with 50% level.For the penetration experiment, fly ash was mixed with soil to prepare different concentrations (5, 10, 20, 30, 40, and 50%. Seeds of pumpkin were grown in coffee cups filled with different mixtures. At two leaf stage, seedlings were inoculated with 2000 larvae. The penetrated larvae in roots were observed after 1, 2, 3, 4, 5, 6 and 7 days. Root penetration was found inversely proportional to concentration. Significant results in the suppression of nematode penetration were noted up to 40% concentration. However, none of the juveniles was penetrated at 50% concentration.International Journal of Environment Vol.5(3 2016, pp.66-73

Comparative oxygen consumption rates of subitaneous and delayed hatching eggs of the calanoid copepod Acartia tonsa (Dana)

DEFF Research Database (Denmark)

Hansen, Benni Winding; Drillet, Guillaume

2013-01-01

nanorespirometry to monitor initial oxygen consumption rate of individual eggs of the ubiquitous neritic calanoid copepod Acartia tonsa to distinguish between subitaneous and DHE. We hypothesized that subitaneous eggs exhibit higher initial oxygen consumption rates than DHE, and that initial egg oxygen consumption...... rate is correlated to the time for the individual egg to hatch. Subitaneous eggs exhibited higher initial oxygen consumption rates than DHE and there were no pattern in initial oxygen consumption rates vs. time to hatch or die from the eggs. Variability in initial oxygen consumption rates within...... batches of both subitaneous and DHE, as well as between these egg types, is prevalent. There was a continuum from sluggish- to fast metabolising eggs considering initial oxygen consumption rates most likely reflecting phenotypic variation within cohorts. No matter the individual initial egg oxygen...

Effect of post-hatch transportation duration and parental age on broiler chicken quality, welfare, and productivity.

Science.gov (United States)

Jacobs, Leonie; Delezie, Evelyne; Duchateau, Luc; Goethals, Klara; Ampe, Bart; Lambrecht, Evelien; Gellynck, Xavier; Tuyttens, Frank A M

2016-09-01

Broiler chicks are transported to production sites within one to 2 d post-hatch. Possible effects of this transportation are poorly understood and could vary among chicks from breeder flocks of different ages. The aim of the present study was to investigate the effects of transportation duration and parental flock age on chick welfare, productivity, and quality. After hatch in a commercial hatchery, 1,620 mixed-sex chicks from 29-wk old (young) and 1,620 chicks from 60-wk old (old) breeders were subjected to transportation of 1.5 h or 11 h duration. After transportation, 2,800 chicks were divided among 100 pens, with each pen containing 28 chicks from one transportation crate (2 or 3 pens per crate). From the remaining chicks, on average 6 chicks (min 4, max 8) per crate (n = 228) were randomly selected and assessed for chick quality, weighed, and culled for yolk sac weighing (one d). Chicks that had not been assigned to pens or were not used for post-transportation measurements, were removed from the experiment (n = 212). Mortality, ADG, BW, and feed conversion ( FC: ) of the experimental chicks were recorded until 41 d. Meat quality was measured for breast fillets (n = 47). No interaction effect of parental age and transportation duration was found for any variables. BW and yolk sac weight at one d were lower for chicks transported 11 h than 1.5 h and for chicks from young versus old breeders. The effect of parental flock age on BW persisted until slaughter. Additionally, parental age positively affected ADG until slaughter. Chick quality was lower in chicks from old versus young breeders. Chick quality and productivity were not affected by transportation duration. Mortality and meat quality were not affected by either parental age or transportation duration. To conclude, no long-term detrimental effects were found from long post-hatch transportation in chicks from young or old parent flocks. Based on these results, we suggest that 11 h post-hatch

Embryo Development and Post-Hatch Performances of Kampung Chicken by in Ovo Feeding of L-Arginine

Directory of Open Access Journals (Sweden)

M. Azhar

2016-12-01

Full Text Available The research was conducted to evaluate embryo development, post-hatch performances, and growth rate of kampung chicken treated in-ovo feeding of L-Arginine. A total of 135 kampung chicken fertile eggs (weight 42-43 g were used and divided into 5 treatment groups of three replications. They were placed in the semi-automatic incubator. The first group was without in-ovo feeding (negative control; the second group was in-ovo feeding of saline 0.9% (positive control; the 3, 4, and 5 groups were in-ovo feeding of 0.5, 1.0, and 1.5% L-Arginine, respectively. In-ovo feeding of L-Arginine were injected into albumen on day 10 of incubation period using automatic syringe in the narrow end side of egg by inserting needle through a small hole at 10 mm depth. After hatching, all day old chicks were placed in floor pens (1 x 0.5 x 0.5 m accordance with the previous egg groups. The results showed that in-ovo feeding of L-Arginine increased weight and circumference of the embryo, but did not affect the length of embryo. In-ovo feeding of L-Arginine resulted in a higher body weight gain and a lower feed conversion even though feed intake was not significantly different compared to the control groups. The growth rate performance up to 6 weeks rearing increased significantly by increasing L-Arginine administration to 1.0%. It can be concluded that embryo development and post-hatch performances of kampung chicken were markedly increased by in-ovo feeding of L-arginine.

Advanced Oxidation Process sanitization of hatching eggs reduces Salmonella in broiler chicks.

Science.gov (United States)

Rehkopf, A C; Byrd, J A; Coufal, C D; Duong, T

2017-10-01

The microbial quality of eggs entering the hatchery is an important critical control point for biosecurity, pathogen reduction, and food safety programs in poultry production. Developing interventions to reduce Salmonella contamination of eggs is important to improving the microbial food safety of poultry and poultry products. The hydrogen peroxide (H2O2) and ultraviolet light (UV) Advanced Oxidation Process (AOP) has been previously demonstrated to be effective in reducing Salmonella on the surface of experimentally contaminated eggs. The objective of this study was to evaluate the effect of treating eggs with an egg-sanitizing apparatus using the H2O2/UV AOP on Salmonella contamination during incubation, hatching, and in broiler chicks during grow-out. Experimentally contaminated eggs were treated using the automated H2O2/UV AOP egg sanitizer and incubated for 21 d. AOP sanitization reduced Salmonella up to 7 log10 cfu egg-1 (P Salmonella positive eggs by up to 75% (P Salmonella-positive eggs during incubation. Additionally, Salmonella was recovered from more chicks hatched from untreated eggs than from eggs treated using the H2O2/UV AOP egg sanitizer (P Salmonella contamination on the surface of eggs using the H2O2/UV AOP egg sanitizer prior to incubation may reduce the gastrointestinal colonization of chicks by Salmonella. © 2017 Poultry Science Association Inc.

Ecotoxicological studies with newly hatched larvae of Concholepas concholepas (Mollusca, Gastropoda): bioassay with secondary-treated kraft pulp mill effluents.

Science.gov (United States)

Manríquez, Patricio H; Llanos-Rivera, Alejandra; Galaz, Sylvana; Camaño, Andrés

2013-12-01

The Chilean abalone or "loco" (Concholepas concholepas, Bruguière 1789) represent the most economically important marine recourse exploited from inner inshore Management and Exploitation Areas for Benthic Resources along the Chilean coast. In this study, newly-hatched larvae of C. concholepas were investigated as a potential model species for marine ecotoxicological studies. The study developed a behavioral standard protocol for assessing the impact that kraft pulp mill effluents after secondary treatment have on C. concholepas larvae. Under controlled laboratory conditions, newly-hatched larvae were exposed to a series of different concentrations of kraft pulp mill effluents with secondary treatment (Pinus spp. and Eucalyptus spp.), potassium dichromate as standard reference toxicant and effluent-free control conditions. Regardless of the type of effluent the results indicated that diluted kraft pulp effluent with secondary treatment had reduced effect on larval survival. Low larval survivals were only recorded when they were exposed to high concentrations of the reference toxicant. This suggests that C. concholepas larval bioassay is a simple method for monitoring the effects of kraft pulp mill effluents with secondary treatment discharged into the sea. The results indicated that dilution of ca. 1% of the effluent with an elemental chlorine free (ECF) secondary treatment is appropriate for achieving low larval mortalities, such as those obtained under control conditions with filtered seawater, and to minimize their impact on early ontogenetic stages of marine invertebrates such as newly-hatched larvae of C. concholepas. The methodological aspects of toxicological testing and behavioral responses described here with newly-hatched larvae of C. concholepas can be used to evaluate in the future the potential effects of other stressful conditions as other pollutants or changes in seawater pH associated with ocean acidification. © 2013 Elsevier Inc. All rights

Diet composition and quality for Calanus finmarchicus egg production and hatching success off south-west Iceland

DEFF Research Database (Denmark)

Jonasdottir, Sigrun; Gudfinnsson, H.G.; Gislason, A.

2002-01-01

Egg production and hatching success of the copepod Calanus finmarchicus was measured during spring and summer in the waters south-west of Iceland. Egg-production rates varied greatly, both temporally and spatially, with highest average rates found at a station with low chlorophyll-a concentrations...

Interannual variations in the hatching pattern, larval growth and otolith size of a sand-dwelling fish from central Chile

Science.gov (United States)

Rodríguez-Valentino, Camilo; Landaeta, Mauricio F.; Castillo-Hidalgo, Gissella; Bustos, Claudia A.; Plaza, Guido; Ojeda, F. Patricio

2015-09-01

The interannual variation (2010-2013) of larval abundance, growth and hatching patterns of the Chilean sand stargazer Sindoscopus australis (Pisces: Dactyloscopidae) was investigated through otolith microstructure analysis from samples collected nearshore (otolith size (radius, perimeter and area), related to body length of larvae, significantly decreased from 2010 to 2012, but increases significantly in 2013. Although the mean values of microincrement widths of sagitta otoliths were similar between 2010 and 2011 (around 0.6-0.7 μm), the interindividual variability increases in 2011 and 2013, suggesting large environmental variability experienced by larvae during these years. Finally, the hatching pattern of S. australis changed significantly from semi-lunar to lunar cycle after 2012.

The Biophysical Characteristics Of Hatching Habitat Of Lekang Turtle (Lepidhochelys olivacea) Eggs In Turtle Conservation And Education Center, Bali

Science.gov (United States)

Suryono; Ario, R.; Wibowo, E.; Handoyo, G.

2018-02-01

Lekang turtle (Lepidhochelys olivacea) is one of the fauna that is protected as an endangered population. This marine reptile was able to migrate in great distance along the Indian Ocean, the Pacific Ocean, and South East Asia. Its existence has long been threatened, either by nature or human activities that endangered the population directly or indirectly. The decreasing number of sea turtle population that nest in Bali area is one indication of the reducing number of Lekang turtle in Indonesia. If left unchecked, it will result in the loss of Lekang turtle. This study aims to determine the successful percentage of conservation techniques and Lekang turtle hatching eggs (olive ridley sea turtle) in TCEC, Bali. The method used in this research is the method of observation or direct observation done in the field. Data collection is done by direct observation in the field. The results showed that the turtle breeding site is located in an area that is less strategic because too far from the sea, so that the temperature and humidity cannot be stable. Water content is most an important factor in the growth of embryo and egg hatching. This will lead to the decrease of hatching percentage of turtle eggs.

Comparing an in vivo egg reduction test and in vitro egg hatching assay for different anthelmintics against Fasciola species, in cattle.

Science.gov (United States)

Arafa, Waleed M; Shokeir, Khalid M; Khateib, Abdelrahman M

2015-11-30

This study aimed to compare between the efficiency of in vivo fecal egg reduction test (FERT) and in vitro egg hatching assay (EHA) in evaluating of the anti-Fasciola activity of albendazole, triclabendazole, oxyclozanide and praziquantel. A field trial was carried out on fifty naturally Fasciola infected cattle that were divided equally into 5 groups (A-E). On day zero; groups A-D were drenched with albendazole, triclabendazole, oxyclozanide or praziquantel, respectively, while the remaining one, group E, was kept as untreated control. Fecal egg counts of the different groups were conducted weekly over a period of one month post-treatment. In vitro, commercial albendazole and oxyclozanide were diluted to 0.0002, 0.002, 0.02, 0.2 and 2.0 μg/ml, while commercial triclabendazole and praziquantel were diluted to concentrations of 25, 50, 75 and 100 μg/ml with dimethyl sulfoxide (DMSO). In vivo, at the 2nd week post-treatment, triclabendazole and oxyclozanide showed 100% fecal egg reduction (FER), and albendazole had a maximum of 73.7% reduction (P egg counts. In vitro, triclabendazole treated Fasciola gigantica eggs showed early embryonic lysis with zero% hatching at the different concentrations (P egg development and hatching percentage of oxyclozanide or praziquantel treated groups. In conclusion, the efficacy of triclabendazole and albendazole as fasciolicdes could be predicted by Egg Hatching Assay (EHA). Meanwhile fasciolicide activity of oxyclozanide could not be assessed with EHA. Based on in vivo and in vitro findings, paraziquantel did not show any fasciolicide effect. Copyright © 2015 Elsevier B.V. All rights reserved.

Thermal and maternal environments shape the value of early hatching in a natural population of a strongly cannibalistic freshwater fish

DEFF Research Database (Denmark)

Pagel, T.; Bekkevold, Dorte; Pohlmeier, S.

2015-01-01

Hatching early in the season is often assumed to elevate fitness, particularly in cannibalistic fish in which size-dependent predation mortality is a major selective force. While the importance of the thermal environment for the growth of fish is undisputed, the relevance of maternal effects...... represented by juvenile growth rate), but not female total length, to jointly contribute to explain within- and among-season size variation in juvenile pike. While there was no statistical evidence for maternal effects on offspring growth rate, fast female juvenile growth positively correlated...... in the wild and that early hatching does not generally produce size advantages in light of stochastically varying temperature conditions...

Effect of vacuum packing and temperature on survival and hatching of strongyle eggs in faecal samples

DEFF Research Database (Denmark)

Sengupta, Mita Eva; Thapa, Sundar; Thamsborg, Stig Milan

2016-01-01

Strongyle eggs of helminths of livestock usually hatch within a few hours or days after deposition with faeces. This poses a problem when faecal sampling is performed in the field. As oxygen is needed for embryonic development, it is recommended to reduce air supply during transport and refrigerate....... The present study therefore investigated the combined effect of vacuum packing and temperature on survival of strongyle eggs and their subsequent ability to hatch and develop into L3. Fresh faecal samples were collected from calves infected with Cooperia oncophora, pigs infected with Oesophagostomum dentatum......, and horses infected with Strongylus vulgaris and cyathostomins. The samples were allocated into four treatments: vacuum packing and storage at 5 °C or 20 °C (5 V and 20 V); normal packing in plastic gloves closed with a loose knot and storage at 5 °C or 20 °C (5 N and 20 N). The number of eggs per gram...

HATCHES - a thermodynamic database and management system

International Nuclear Information System (INIS)

Cross, J.E.; Ewart, F.T.

1990-03-01

The Nirex Safety Assessment Research Programme has been compiling the thermodynamic data necessary to allow simulations of the aqueous behaviour of the elements important to radioactive waste disposal to be made. These data have been obtained from the literature, when available, and validated for the conditions of interest by experiment. In order to maintain these data in an accessible form and to satisfy quality assurance on all data used for assessments, a database has been constructed which resides on a personal computer operating under MS-DOS using the Ashton-Tate dBase III program. This database contains all the input data fields required by the PHREEQE program and, in addition, a body of text which describes the source of the data and the derivation of the PHREEQE input parameters from the source data. The HATCHES system consists of this database, a suite of programs to facilitate the searching and listing of data and a further suite of programs to convert the dBase III files to PHREEQE database format. (Author)

Embryonic exposure of medaka (Oryzias latipes) to propylparaben: Effects on early development and post-hatching growth

International Nuclear Information System (INIS)

González-Doncel, Miguel; García-Mauriño, José Enrique; San Segundo, Laura; Beltrán, Eulalia M.; Sastre, Salvador; Fernández Torija, Carlos

2014-01-01

Here we proposed a battery of non-invasive biomarkers and a histological survey to examine physiological/anatomical features in embryos, eleutheroembryos (13 days post-fertilization, dpf), and larvae (28–42 dpf) of medaka to investigate the effects of embryonic exposure to propylparaben (PrP). Concentrations <1000 μg PrP/L didn't exert early or late toxic effects. However, survivorship was affected at 4000 μg/L in eleutheroembryos and at ≥1000 μg/L in larvae. Histological alterations were found in 37.5% of eleutheroembryos exposed to 4000 μg PrP/L. Morphometric analysis of the gallbladder revealed significant dilation at ≥400 μg/L throughout embryo development. Ethoxyresorufin-O-deethylase (EROD), as indicator of cytochrome P4501A activity, didn't reveal induction/inhibition although its combination with a P4501A agonist (i.e. β-naphthoflavone) resulted in a synergic EROD response. Results suggest a low toxicity of PrP for fish and support the use of fish embryos and eleutheroembryos as alternatives of in vivo biomarkers indicative of exposure/toxicity. -- Highlights: • Addressing pre- and post-hatch effects from medaka embryo exposure to propylparaben. • Macroscopical effects (length, mortality) seen primarily after hatch at ≥400 μg/L. • Synergic EROD embryonic response when propylparaben combined with a CYP1A agonist. • Significant gallbladder dilation seen at ≥400 μg PrP/L and as soon as discernible. • Histological harm to eleutheroembryos in peritoneal cavity, liver, kidney and brain. -- PrP resulted in low toxicity based on non-invasive biomarkers and histological tools to analyze pre- and post-hatch effects after medaka embryo exposure

Snapping turtles (Chelydra serpentina) as bioindicators in Canadian Areas of Concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants

Energy Technology Data Exchange (ETDEWEB)

Solla, S.R. de , [Population Assessment Unit, Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, ON, L7R 4A6 (Canada); Fernie, K J; Ashpole, S [Population Assessment Unit, Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, ON, L7R 4A6 (Canada)

2008-06-15

Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities. - Hatching success and deformities of snapping turtle eggs varied among Great Lake Areas of Concern, but were not attributable to specific chemical exposure.

Snapping turtles (Chelydra serpentina) as bioindicators in Canadian Areas of Concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants

International Nuclear Information System (INIS)

Solla, S.R. de; Fernie, K.J.; Ashpole, S.

2008-01-01

Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities. - Hatching success and deformities of snapping turtle eggs varied among Great Lake Areas of Concern, but were not attributable to specific chemical exposure

Effects of catechins and low temperature on embryonic development and hatching in Heterodera glycines and Meloidogyne incognita

Science.gov (United States)

Mimics of two natural influences, a chemical similar to one present in cyst nematodes and low temperature exposure of nematode eggs, were evaluated for their effects on quantitative and qualitative features of embryonic development and hatching. The polyphenol epigallocatechin gallate (EGCG), an ana...

Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

Energy Technology Data Exchange (ETDEWEB)

Ryan, Kathleen M. [State Univ. of New York (SUNY),Buffalo, NY (United States)

1990-12-01

The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26°C and downshifted 30-26-30°C) and females (constant 30°C and upshifted 26-30-26°C) under constant and altered temperature regimes. The incubation conditions resulted in 92% males from the constant 26°C group and 93% males from the downshifted group. 100% females resulted from both the constant 30°C group and the upshifted group. Turtles hatching from eggs incubated constantly at 26°C were significantly larger than hatchlings from eggs incubated at a constant 30°C or downshifted. Hatchlings were raised in individual aquaria at 25°C and fed earthworms and fish. After a 9-month growth period, turtles which had been incubated at a constant 30°C gained significantly more mass than did turtles from eggs which had been downshifted or upshifted. There was no extended effect of incubation condition on Post-hatching performance and learning ability as measured by righting and feeding responses. Thus, the mass gain differences seen in this study suggest that physiological differences do result as the consequence of incubation condition. However, these physiological differences are not reflected in normal locomotive or feeding behavior.

Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

Energy Technology Data Exchange (ETDEWEB)

Ryan, K.M.

1990-12-01

The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26[degree]C and downshifted 30-26-30[degree]C) and females (constant 30[degree]C and upshifted 26-30-26[degree]C) under constant and altered temperature regimes. The incubation conditions resulted in 92% males from the constant 26[degree]C group and 93% males from the downshifted group. 100% females resulted from both the constant 30[degree]C group and the upshifted group. Turtles hatching from eggs incubated constantly at 26[degree]C were significantly larger than hatchlings from eggs incubated at a constant 30[degree]C or downshifted. Hatchlings were raised in individual aquaria at 25[degree]C and fed earthworms and fish. After a 9-month growth period, turtles which had been incubated at a constant 30[degree]C gained significantly more mass than did turtles from eggs which had been downshifted or upshifted. There was no extended effect of incubation condition on Post-hatching performance and learning ability as measured by righting and feeding responses. Thus, the mass gain differences seen in this study suggest that physiological differences do result as the consequence of incubation condition. However, these physiological differences are not reflected in normal locomotive or feeding behavior.

Community structure, life histories and secondary production of stoneflies in two small mountain streams with different degree of forest cover

Directory of Open Access Journals (Sweden)

Pavel Beracko

2015-10-01

Full Text Available Our study examines community structure and nymphal biology (life cycles and secondary production of stoneflies in two adjacent mountain streams with different degree of forest cover in the Prosiečanka River Basin (Chočské Vrchy Mts., West Carpathians. One of the streams has non-forested catchment, converted to meadows and pastures, while the other one has catchment with 60% covered by spruce forest. Differences in forest cover and in thermal regime of the streams were reflected by the difference of stonefly communities at their structural and functional level. Species Nemoura cinerea and Leuctra aurita created stonefly assemblage in non-forested stream, whereas Nemoura cinerea also occurred in naturally forested stream together with species Leuctra armata, Leuctra nigra, Leuctra prima, Siphonoperla neglecta and Arcynopteryx dichroa. All examined species had maximally annual life cycle and in eudominant species Nemoura cinerea one month shift was found in nymphal hatching and adult emergence between streams. Total secondary production of stoneflies in undisturbed stream (126.46 mg DW m-2 y-1 was more than two times higher than the production in non-forested stream (47.39 mg DW m-2 y-1. 

Information needs, sources, and decision-making by hatching egg and broiler chicken producers: A qualitative study in Alberta, Canada.

Science.gov (United States)

Anholt, R Michele; Russell, Margaret; Inglis, Tom; Mitevski, Darko; Hall, David

2017-05-01

Understanding the sources and use of information from hatching egg and broiler chicken producers, their constraints, and unmet information needs can help define future research agendas. This report presents the results from a qualitative study using interviews of 11 hatching egg producers and 12 broiler producers in Alberta, Canada. Patterns were reported and described using thematic analysis. Producers recognized that there were numerous sources of information available to them for managing disease in their flocks. Complex disease issues such as early mortality were discussed, but many producers did not believe they had any influence over the outcomes and did not see a benefit from additional information to improve outcomes. Producers described their experience, trust in the information source, and the usefulness of the information for decision-making as necessary for information uptake.

Snapping turtles (Chelydra serpentina) as bioindicators in Canadian areas of concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants.

Science.gov (United States)

de Solla, S R; Fernie, K J; Ashpole, S

2008-06-01

Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities.

Theoretical and empirical studies on temperature and moisture loss of hatching eggs during the pre-incubation period

NARCIS (Netherlands)

Meijerhof, R.

1994-01-01

In the Netherlands, approximately 800 million hatching eggs per year are produced on highly specialized broiler breeder farms. On this farms, the eggs are produced and stored for several days. Normally once or twice a week the eggs are collected from the farms and transported to the

Effects of in ovo feeding of cationic amino acids on hatchability, hatch weights, and organ developments in domestic pigeon squabs (Columba livia).

Science.gov (United States)

Zhang, X Y; Li, L L; Miao, L P; Zhang, N N; Zou, X T

2018-01-01

This study was conducted to evaluate the effect of in ovo feeding of cationic amino acids on hatchability, hatch weights, and organ developments in pigeon squabs. Two experiments were conducted in this study. Eggs in Exp. 1 were subjected to modification of in ovo feeding in pigeons. Optimal time was determined by checking amniotic fluid volume, and suitable length was confirmed through ink injection. Results showed that the optimum time of in ovo feeding was on d 13 of embryonic development, and the suitable injected length was 20 mm to reach the amniotic cavity of the embryo. Eggs in Exp. 2 were transferred to access in ovo feeding of cationic amino acids. A total of 75 fertile pigeon eggs was randomly distributed into 5 treatments of 15 replicate eggs. Treatments in Exp. 2 consisted of non-injected controls (Control), a sterile buffered solution (0.75% saline), or a cationic amino acid mixture (> 98.5% purity crystalline L-arginine, > 98% purity crystalline L-lysine, and > 98.5% purity L-histidine) containing 0.1, 1, or 10% concentration (Conc.), which were relative to their total content in the eggs, respectively. The crystalline amino acids were dissolved in 200 μL buffered solution prior to in ovo feeding. After hatching, hatch weight (HW) and organ weight (OW) of the squabs were measured immediately. In ovo feeding of cationic amino acids increased the proportions of yolk-free hatch weight to hatch weight (YFHW/HW) (quadratic P = 0.01), and those of OW to YFHW including the heart (quadratic P = 0.01), kidney (quadratic P < 0.01), and liver (quadratic P = 0.02) compared to the control group, and the levels of those ratios were maximized in the 1% Conc group. Also, a proportion of small intestine weight to YFHW improved (linear P = 0.02, quadratic P = 0.05) after in ovo feeding. The organ weight of the head, leg, heart, lung, kidney, proventriculus, pancreas, liver, and small intestine correlated with YFHW positively (0.4 < correlation coefficient < 0

Latex constituents from Calotropis procera (R. Br. display toxicity upon egg hatching and larvae of Aedes aegypti (Linn.

Directory of Open Access Journals (Sweden)

Márcio Viana Ramos

2006-08-01

Full Text Available Calotropis procera R. Br. (Asclepiadaceae is a well-known medicinal plant with leaves, roots, and bark being exploited by popular medicine to fight many human and animal diseases. This work deals with the fractionation of the crude latex produced by the green parts of the plant and aims to evaluate its toxic effects upon egg hatching and larval development of Aedes aegypti. The whole latex was shown to cause 100% mortality of 3rd instars within 5 min. It was fractionated into water-soluble dialyzable (DF and non-dialyzable (NDF rubber-free materials. Both fractions were partially effective to prevent egg hatching and most of individuals growing under experimental conditions died before reaching 2nd instars or stayed in 1st instars. Besides, the fractions were very toxic to 3rd instars causing 100% mortality within 24 h. When both fractions were submitted to heat-treatment the toxic effects were diminished considerably suggesting low thermostability of the toxic compounds. Polyacrylamide gel electrophoresis of both fractions and their newly fractionated peaks obtained through ion exchange chromatography or desalting attested the presence of proteins in both materials. When submitted to protease digestion prior to larvicidal assays NDF lost most of its toxicity but DF was still strongly active. It may be possible that the highly toxic effects of the whole latex from C. procera upon egg hatching and larvae development should be at least in part due to its protein content found in NDF. However the toxicity seems also to involve non protein molecules present in DF.

Effect of brood size and hatching sequence on prefledging mortality of Sandwich terns: why lay two eggs?

NARCIS (Netherlands)

Stienen, E.W.M.; Brenninkmeijer, A.

2006-01-01

The mortality of Sandwich tern Sterna sandvicensis chicks held in enclosures was studied in colonies on Griend, in the Dutch Wadden Sea, from 1992 to 1999, and on Hirsholm, in the Danish Kattegat, in 1997. Survival of chicks until fledging was 73% for chicks hatching from first-laid eggs or

Effect of brood size and hatching sequence on prefledging mortality of Sandwich terns : why lay two eggs?

NARCIS (Netherlands)

Stienen, Eric W. M.; Brenninkmeijer, Alex

2006-01-01

The mortality of Sandwich tern Sterna sandvicensis chicks held in enclosures was studied in colonies on Griend, in the Dutch Wadden Sea, from 1992 to 1999, and on Hirsholm, in the Danish Kattegat, in 1997. Survival of chicks until fledging was 73% for chicks hatching from first-laid eggs or

Recovery of salmonella serovar enteritidis from inoculated broiler hatching eggs using shell rinse and shell crush sampling methods

Science.gov (United States)

This study compared the recovery of Salmonella from hatching eggs using three sampling methods (eggshell rinsing, eggshell crush following a previous rinse, and eggshell crush without previous rinse). Eggshells were drop-inoculated with approximately 10, 100, or 1,000 cfu/eggshell of S. Enteritidis...

Examination of overlay pipe weldments removed from the Hatch-2 reactor

International Nuclear Information System (INIS)

Park, J.Y.; Kupperman, D.S.; Shack, W.J.

1985-02-01

Laboratory ultrasonic examination (UT), dye penetrant examination (PT), metallography, and sensitization measurements were performed on Type 304 stainless steel overlay pipe weldments from the Hatch-2 BWR to determine the effectiveness of UT through overlays and the effects of the overlays on crack propagation in the weldments. Little correlation was observed between the results of earlier in-service ultrasonic inspection and the results of PT and destructive examination. Considerable difficulty was encountered in correctly detecting the presence of cracks by UT in the laboratory. Blunting of the crack tip by the weld overlay was observed, but there was no evidence of tearing or throughwall extension of the crack beyond the blunted region

Crystallization and preliminary X-ray analysis of ZHE1, a hatching enzyme from the zebrafish Danio rerio

International Nuclear Information System (INIS)

Okada, Akitoshi; Nagata, Koji; Sano, Kaori; Yasumasu, Shigeki; Kubota, Keiko; Ohtsuka, Jun; Iuchi, Ichiro; Tanokura, Masaru

2009-01-01

The hatching enzyme of zebrafish, ZHE1, was expressed, purified and crystallized using the hanging-drop vapour-diffusion method. The crystal belonged to space group P2 1 2 1 2 1 and diffracted X-rays to a resolution of 1.14 Å. The hatching enzyme of the zebrafish, ZHE1 (29.3 kDa), is a zinc metalloprotease that catalyzes digestion of the egg envelope (chorion). ZHE1 was heterologously expressed in Escherichia coli, purified and crystallized by the hanging-drop vapour-diffusion method using PEG 3350 as the precipitant. Two diffraction data sets with resolution ranges 50.0–1.80 and 50.0–1.14 Å were independently collected from two crystals and were merged to give a highly complete data set over the full resolution range 50.0–1.14 Å. The space group was assigned as primitive orthorhombic P2 1 2 1 2 1 , with unit-cell parameters a = 32.9, b = 62.5, c = 87.4 Å. The crystal contained one ZHE1 molecule in the asymmetric unit

Studies on improving ostrich egg hatch ability and its relation with some factors affecting embryonic development during artificial incubation

International Nuclear Information System (INIS)

Amer, N.S.I.

2012-01-01

The present study was carried out in co-operation between the Ostrich Production Farm, Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt and the Faculty of Agriculture, AL-Azhar University, Nasr City, Cairo, Egypt. Ostrich eggs were obtained from Resk Company for Ostrich Production and set for incubation at ElShfie Farm, Belbas, Sharkia, Egypt. The objectives are:1- To follow up changes in some vital physiological parameters and blood components associated with ostrich embryonic development during incubation and to provide reference blood biochemical baseline values for future studies of avian species and to document novel information on some normal changes associated with growth of the developing ostrich embryo during the incubation, as no similar and complete data could be found on this aspect in the literature. 2- In an effort to improve the hatch ability and hatching performance of ostrich eggs by testing the effect of in ovo injection of several nutrients. Two trials were carried out: 1-First trial To follow up changes in some vital physiological parameters and blood components associated with ostrich embryonic development during incubation. A total number of 60 ostrich eggs weighed between 1300 and 1500 g were obtained from from Resk Company for Ostrich Production. Eggs were collected weekly in patches of 25 eggs and Egg incubation was performed in ElShfie Farm, Belbas, Egypt. Egg weight and egg weight loss during incubation were determined on each eggs.2- Second Trial In vivo injection In an effort to improve the hatch ability and hatching performance of ostrich eggs by testing the effect of in ovo injection of several nutrients. A total of 100 fertile ostrich eggs weighed between 1300 and 1500 g were obtained from from Resk Company for Ostrich Production. Eggs were collected weekly in patches of 25 eggs and egg incubation was performed in ElShfie Farm, Belbas, Egypt. Eggs were injected at the 7 th day of incubation to deposit test material in

Evaluation of disinfectants and antiseptics to eliminate bacteria from the surface of turkey eggs and hatch gnotobiotic poults

Science.gov (United States)

Bird eggs and are in contact with intestinal microbiota prior to oviposition, but are protected from bacterial translocation by a glycoprotein cuticle layer, the shell and internal membranes. In a preliminary study, turkey eggs were hatched in a germ-free environment. Firmicutes 16S rRNA gene was de...

Effect of electron irradiation on hatchability and broiler performance of hatching eggs

International Nuclear Information System (INIS)

Castaneda, S.M.P.; Tellez, I.G.; Sanchez, R.E.; Quintana, L.J.A.; Bustos, R.E.

1996-01-01

The irradiation of foods employs the electromagnetic ionizing energy, and the gamma ray, the X ray and the electrons are used. The electrons are reduced mass particles and have negative electric charge. The difference between the gamma rays, X-ray and electron is the penetration level. The effective range on penetration of electron accelerator depends on the energy level, in practice the penetation of an electron beam in the foods is 5 mm for MeV. The objectives of this work were to evaluate the effects of electron irradiation on the hatchability, and to evaluate the productive parameters of chicken hatching from egg irradiated with electrons. (author). 15 refs., 6 tabs

An egg injection technique to evaluate the effect of polychlorinated biphenyls on the hatching success of the snapping turtle (Chelydra serpentina serpentina).

Science.gov (United States)

Schnars, Jeanette L; Voss, Margaret A; Stauffer, Jay R

2011-04-01

Embryos of oviparous organisms are exposed to contaminants by two pathways: contaminant uptake from the surrounding environment, and the transfer from female to offspring (maternal transfer). The initial source of contaminant exposure for most embryos is likely to be maternal transfer; therefore, maternal transfer studies are critical in determining the effects of contaminants on future populations. Injection of contaminants directly into eggs is one route of experimental contaminant exposure that permits controlled doses and potential reliable replication. This technique, however, has been used in the past with little success in reptiles. The objective of the present study was to evaluate egg injection as a means of mimicking maternal transfer of polychlorinated biphenyls (PCBs) to snapping turtle eggs. Eggs from several clutches were injected with a PCB solution and incubated at several temperatures and moisture levels to measure interactive effects of injection, environmental condition, and contaminant load on hatching success. The injection technique allowed for application of consistent and specific doses among replicates. Overall hatching success in this study was 61% and was as high as 71% within specific treatments. Hatching success was much higher in this study than in other studies using egg injections to mimic maternal transfer in chelonians and crocodilians. Copyright © 2010 SETAC.

A meta-analysis of effects of post-hatch food and water deprivation on development, performance and welfare of chickens

NARCIS (Netherlands)

Jong, de I.C.; Riel, van J.W.; Bracke, M.B.M.; Brand, van den H.

2017-01-01

A ‘meta-analysis’ was performed to determine effects of post-hatch food and water deprivation (PHFWD) on chicken development, performance and welfare (including health). Two types of meta-analysis were performed on peer-reviewed scientific publications: a quantitative ‘meta-analysis’ (MA) and a

EFFECT OF STORAGE TEMPERATURE PERCENTAGE OF EGG HATCHING OF AEDES AEGYPTI IN LABORATORY=PENGARUH SUHU PENYIMPANAN TERHADAP PRESENTASE TETAS TELUR Aedes aegypti DI LABORATORIUM

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Riyani Setiyaningsih

2015-03-01

Full Text Available EnglishABSTRACTAedes aegypti is the vector of Dengue Hemorrhagic Fever (DHF in Indonesia. Ae. aegypti has a high reproductive capacity, one female mosquitoes can lay 100-150 eggs. Eggs of Ae. aegypti can survive on dry temperatures within a few months, thus increasing the chances of transmission of dengue virus The aim of the study was to determine the effect of temperature on egg hatching percentage of Ae. aegypti. Eggs Ae. aegypti colonization in laboratory results are stored at room temperature and refrigerator temperature. Observations percentage of eggs hatching was observed at month zero, one, two, third, fourth, fifth, and sixth. The results of the study until the sixth month percentage of hatching eggs at room temperature was 63,17, 59,26, 24,33, 13,62, 10, and 0%. While storage on egg hatching refrigerator not occur in the first to sixth.INDONESIANAedes aegypti merupakan vektor Demam Berdarah Dengue (DBD di Indonesia. Ae. aegypti memiliki kemampuan reproduksi yang tinggi, satu ekor nyamuk betina dapat bertelur 100-150 butir telur. Telur Ae. aegypti mampu bertahan hidup pada suhu kering dalam beberapa bulan sehingga memperbesar peluang terjadinnya proses penularan virus DBD. Tujuan penelitian adalah mengetahui pengaruh suhu dan lama penyimpanan terhadap presentase penetasan telur Ae. aegypti. Telur Ae. aegypti hasil kolonisasi di laboratorium disimpan pada suhu ruang dan suhu refrigerator. Pengamatan presentase penetasan telur diamati pada bulan ke nol, kesatu, kedua, ketiga, keempat, kelima, dan keenam. Hasil penelitian pada bulan bertama sampai keenam presentase penetasan telur pada suhu ruang adalah 63,17, 59,26, 24,33, 13,62, 10, dan 0%. Sedangkan penyimpanan pada suhu kukas tidak terjadi penetasan telur pada bulan pertama sampai keenam.

Susceptibility of in vitro produced hatched bovine blastocysts to infection with bluetongue virus serotype 8

Directory of Open Access Journals (Sweden)

Vandaele Leen

2011-01-01

Full Text Available Abstract Bluetongue virus serotype 8 (BTV-8, which caused an epidemic in ruminants in central Western Europe in 2006 and 2007, seems to differ from other bluetongue serotypes in that it can spread transplacentally and has been associated with an increased incidence of abortion and other reproductive problems. For these reasons, and also because BTV-8 is threatening to spread to other parts of the world, there is a need for more information on the consequences of infection during pregnancy. The aim of the present study was to investigate whether hatched (i.e. zona pellucida-free in vitro produced bovine blastocysts at 8-9 days post insemination are susceptible to BTV-8 and whether such infection induces cell death as indicated by apoptosis. Exposure of hatched in vitro produced bovine blastocysts for 1 h to a medium containing 103.8 or 104.9 TCID50 of the virus resulted in active viral replication in between 25 and 100% of the cells at 72 h post exposure. The infected blastocysts also showed growth arrest as evidenced by lower total cell numbers and a significant level of cellular apoptosis. We conclude from this in vitro study that some of the reproductive problems that are reported when cattle herds are infected with BTV-8 may be attributed to direct infection of blastocysts and other early-stage embryos in utero.

Presence of antimicrobial resistance in coliform bacteria from hatching broiler eggs with emphasis on ESBL/AmpC-producing bacteria.

Science.gov (United States)

Mezhoud, H; Chantziaras, I; Iguer-Ouada, M; Moula, N; Garmyn, A; Martel, A; Touati, A; Smet, A; Haesebrouck, F; Boyen, F

2016-08-01

Antimicrobial resistance is recognized as one of the most important global health challenges. Broilers are an important reservoir of antimicrobial resistant bacteria in general and, more particularly, extended-spectrum β-lactamases (ESBL)/AmpC-producing Enterobacteriaceae. Since contamination of 1-day-old chicks is a potential risk factor for the introduction of antimicrobial resistant Enterobacteriaceae in the broiler production chain, the presence of antimicrobial resistant coliform bacteria in broiler hatching eggs was explored in the present study. Samples from 186 hatching eggs, collected from 11 broiler breeder farms, were inoculated on MacConkey agar with or without ceftiofur and investigated for the presence of antimicrobial resistant lactose-positive Enterobacteriaceae, particularly, ESBL/AmpC-producers. Escherichia coli and Enterobacter cloacae were obtained from the eggshells in 10 out of 11 (10/11) sampled farms. The majority of the isolates were recovered from crushed eggshells after external decontamination suggesting that these bacteria are concealed from the disinfectants in the egg shell pores. Antimicrobial resistance testing revealed that approximately 30% of the isolates showed resistance to ampicillin, tetracycline, trimethoprim and sulphonamides, while the majority of isolates were susceptible to amoxicillin-clavulanic acid, nitrofurantoin, aminoglycosides, florfenicol, neomycin and apramycin. Resistance to extended-spectrum cephalosporins was detected in eight Enterobacteriaceae isolates from five different broiler breeder farms. The ESBL phenotype was confirmed by the double disk synergy test and blaSHV-12, blaTEM-52 and blaACT-39 resistance genes were detected by PCR. This report is the first to present broiler hatching eggs as carriers and a potential source of ESBL/AmpC-producing Enterobacteriaceae for broiler chicks.

Impact of environmental factors on recruitment and hatching patterns of Horse Mackerel (L. collected in a nearshore rocky reef system

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Maria Klein

2015-11-01

Full Text Available Horse mackerel (Trachurus trachurus, Linnaeus, 1758 is a highly exploited fish species, common throughout the North-East Atlantic. As a pelagic-neritic fish it typically occurs over the shelf at 100-200 m depth on sandy bottom and most research has focused on adults or early life stages (eggs and larvae, caught or examined in deeper waters. Nevertheless, larvae and early stages of Trachurus species have been observed in the nearshore environment of a rocky reef system in Portugal. More research is needed in order to understand the importance of nearshore environments for horse mackerel. In addition little is known on how environmental processes might affect early life parameters of this species. In this study we monitored the arrival of early juvenile horse mackerel to the reef environment at a fine time scale, and analyzed the relationship of environmental factors with patterns of recruitment and hatching, revealed by otolith microstructure analysis. In total around 2500 fish were collected with Standard Monitoring Units for the Recruitment of Fish (SMURF and a distinct depth preference was recorded as 99% of fish were sampled with surface SMURFs. A GAM and GAMM analysis of the recruitment and hatching pattern, respectively, revealed a strong relationship with the lunar cycle and local up-welling. Both recruitment and hatching had a periodic pattern with peaks near the new moon; upwelling had a negative impact. Further, the study indicated that the nearshore environment might be an important nursery area for the post-larval growth of horse mackerel.

Edwin I. Hatch Nuclear Plant, Unit 1. Semiannual operating report, September 12--December 31, 1974

International Nuclear Information System (INIS)

1974-01-01

Hatch-1 achieved initial criticality on September 12, 1974, and initial synchronization on November 11, 1974. The unit is a BWR of 813 MW(e) and has generated 50,775.6 MWH since September 12 with the generator on line 865.62 hours. Net plant efficiency was 20.88 percent with plant availability of 28.32 percent. Information is presented concerning operations, changes, tests, safety related maintenance, primary coolant chemistry, occupational personnel radiation doses, and radioactive effluent releases. (U.S.)

Car Covers | Outdoor Covers Canada

OpenAIRE

Covers, Outdoor

2018-01-01

Protect your car from the elements with Ultimate Touch Car Cover. The multi-layer non-woven fabric is soft on the finish and offers 4 seasons all weather protection.https://outdoorcovers.ca/car-covers/

Effect of quercetin on the number of blastomeres, zona pellucida thickness, and hatching rate of mouse embryos exposed to actinomycin D: An experimental study

Directory of Open Access Journals (Sweden)

Hamid Reza Sameni

2018-02-01

Full Text Available Background: Quercetin is a flavonoid with the ability to improve the growth of embryos in vitro, and actinomycin D is an inducer of apoptosis in embryonic cells. Objective: The aim was to evaluate the effect of quercetin on the number of viable and apoptotic cells, the zona pellucida (ZP thickness and the hatching rate of preimplantation embryos exposed to actinomycin D in mice. Materials and Methods: Two-cell embryos were randomly divided into four groups (Control, Quercetin, actinomycin D, and Quercetin + actinomycin D group. Blastocysts percentage, hatched blastocysts, and ZP thickness of blastocysts was measured. The number of blastomeres was counted by Hoechst and propidium iodide staining and the apoptotic cells number was counted by TUNEL assay. Results: The results showed that the use of quercetin significantly improved the growth of embryos compared to the control group (p=0.037. Moreover, quercetin reduced the destructive effects of actinomycin D on the growth of embryos significantly (p=0.026. Conclusion: quercetin may protect the embryos against actinomycin D so that increases the number of viable cells and decreases the number of apoptotic cells, which can help the expansion of the blastocysts, thinning of the ZP thickness and increasing the hatching rate in mouse embryos.

Temperature during the last week of incubation. I. Effects on hatching pattern and broiler chicken embryonic organ development

NARCIS (Netherlands)

Maatjens, C.M.; Roovert-Reijrink, van I.A.M.; Engel, B.; Pol, van der C.W.; Kemp, B.; Brand, van den H.

2016-01-01

We investigated the effects of an eggshell temperature (EST) of 35.6, 36.7, 37.8, and 38.9°C applied from d of incubation (E) 15, E17, and E19 on hatching pattern and embryonic organ development. A total of 2,850 first-grade eggs of a 43-week-old Ross 308 broiler breeder flock were incubated at an

Numerical simulation of an equipment hatch for a steel containment vessel to loading beyond the design basis

International Nuclear Information System (INIS)

Kulak, R.F.; Hsieh, B.J.; Ash, J.E.; Kennedy, J.M.; McLennan, G.A.

1985-01-01

A preliminary analysis of the sealing deformations of a large equipment hatch with a pressure-seated gasket due to overpressurization was performed. An axisymmetric finite element analysis of the penetration sleeve revealed that its surface can undergo large rotations; values for sealing surface rotation of 7 0 were computed. Estimates for the order of magnitude of leakage due to the sealing surface rotation were made. 10 refs., 7 figs., 1 tab

Effect of Linear Alkylbenzene Sulfonate on Mortality, Hatching Rate of Eggs and Abnormality of Catfish (Pangasius hypophthalmus Sauvage Larvae

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E. Supriyono

2007-01-01

Full Text Available Linear alkylbenzene sulfonate (LAS surfactant in the water can affecting fish in all developmental stages.  This study was aimed to observe the effect of LAS on mortality, hatching rate of eggs, and abnormality of patin catfish (Pangasius hypophthalmus Sauvage larvae.   Fertilized eggs were incubated in water containing LAS at the dosages of 0.0, 0.5, 1.5, 3.0, 9.0, and 18.0 mg/L.  Eggs mortality was observed every 6 hours until larvae hatched (24 hours.  The results of study showed that the exposure of 18.0 mg LAS per liter water could put to death all the fertilized eggs and larvae be abnormal.  The exposure of LAS at concentration of 9.0 mg/L could kill 98% of eggs and hatching rate was only 2%.  The abnormality in larvae was bending in the body and tails. Keywords: patin catfish, Pangasius, Linear Alkylbenzene Sulfonate, LAS, abnormality   ABSTRAK Surfaktan Linear Alkylbenzene Sulfonate (LAS yang masuk ke dalam perairan sangat berpengaruh terhadap ikan dari stadia awal hidup ikan sampai dewasa. Penelitian ini bertujuan untuk mengetahui pengaruh LAS terhadap mortalitas, daya tetas telur dan abnormalitas larva ikan patin (Pangasius hypophthalmus Sauvage.  Telur ikan patin yang telah dibuahi di rendam dalam air yang mengandung LAS dengan konsentrasi 0,0; 0,5; 1,5; 3,0; 9,0 dan 18,0 mg/L.  Mortalitas telur dicatat setiap 6 jam sampai menetas (24 jam.  Hasil penelitian menunjukkan bahwa konsentrasi LAS sebesar 18,0 mg/L dapat mengakibatkan mortalitas telur dan abnormalitas pada larva secara total.  Konsentrasi LAS sebesar 9,0 mg/L dapat mematikan telur hingga 98% dan hanya menghasilkan daya tetas sebanyak 2%. Abnormalitas pada larva berupa pembengkokan pada tubuh dan ekor. Kata kunci: ikan patin, Pangasius, Linear Alkylbenzene Sulfonate, LAS dan abnormalitas

Hatching delays in great tits and blue tits in response to an extreme cold spell: a long-term study

Science.gov (United States)

Glądalski, Michał; Bańbura, Mirosława; Kaliński, Adam; Markowski, Marcin; Skwarska, Joanna; Wawrzyniak, Jarosław; Zieliński, Piotr; Bańbura, Jerzy

2018-04-01

Variation in ambient temperature affects various life stages of organisms. It has been suggested that climate change not only implies higher global temperatures but also more unpredictable weather and more frequent extreme weather events. Temperature has a major influence on the optimal laying-incubation-hatching dates of insectivorous passerines, because it poses energetic constraints and affects the timing of food abundance. We have been studying breeding characteristics of great tits Parus major and blue tits Cyanistes caeruleus in two areas, an urban parkland and a deciduous forest, around the city of Łódź since 2002. During the egg-laying period in 2017, both tit species at both study areas faced an unusual cold spell as reflected by a sudden decrease in the mean ambient temperature to ca. 2-3 °C for about 5 days, which caused mean hatching delays of up to 6 days. Since flexibility of behavior plays a major role in adjusting to unpredictable weather conditions, examining its limits may be an important goal for future research.

License renewal - an idea whose time has come. Hatch nuclear plant license renewal program: an actual example of application of the license renewal rule to the Intake Structure

International Nuclear Information System (INIS)

Chandiwala, F.; Evans, W.P.

1999-01-01

After the NRC issued a revised license renewal rule in May 1995, the nuclear industry focussed on developing generic industry for implementing the rule and testing the guidance through various demonstration programs and work products in conjunction with the NRC. In addition, plant-specific programs also proceeded forward. These activities show that implementation issues continue to exist. Since the issuance of the rule, the NRC has issued a draft standard review plan for license renewal (SRP-LR), working draft, September 1997. Southern Nuclear Operating Company (SNC) has begun development work on a license renewal application for Plant Hatch Units 1 and 2. Plant Hatch Units 1 and 2 are BWR 4, Mark I plants whose operating licenses expire in 2014 and 2018, respectively. The Plant Hatch initiative also involves teaming with other boiling water reactors (BWRs) to develop the license renewal technology within the BWR fleet, and to support Plant Hatch by providing an oversight role for the application process. The teaming effort involved two other utilities, each being assigned to prepare a common report on a mechanical system or a structure. The common report could be presented to the NRC with modifications to suit the individual plants, thereby saving time and money, and hopefully resulting in quicker approval by the NRC. The desired license renewal process end result is a renewed license with up to a 20 year extension (10CFR 54.31(b)). (orig.)

THE EFFECT OF IMMERSION LENGTH IN PAPAYA LEAF SOLUTION (CARICA PAPAYA L. TOWARD FERTILIZATION AND HATCHING OF IRIDESCENT SHARKS (PANGASIANODON HYPOPHTHALMUS S.

Directory of Open Access Journals (Sweden)

Eka S.H.

2018-02-01

Full Text Available Iridescent sharks is one kind of freshwater fish that is quite economical. However, the availability of the fish eggs is rather problematic due to the hatcheries, i.e. the adhesive nature of the eggs. Papaya leaves contain papain enzymes that can reduce the adhesive nature of eggs. The purpose of this study was to determine the effect of papaya leaf solution with different immersion period on the successful hatching of the iridescent sharks (P. hypophthalmus. This study was conducted experimentally using a complete randomized design. There were five treatments, i.e. (K 0 seconds, (A 30 seconds, (B 60 seconds, (C 90 seconds, (D 120 seconds, and (E 150 seconds with three-time repetition. The result of this study shows that the best hatching (80.31% happens to the eggs immersed in papaya leaf solution for 60 seconds (treatment B.

From facultative to obligatory parental care: Interspecific variation in offspring dependency on post-hatching care in burying beetles

Science.gov (United States)

Capodeanu-Nägler, Alexandra; Keppner, Eva M.; Vogel, Heiko; Ayasse, Manfred; Eggert, Anne-Katrin; Sakaluk, Scott K.; Steiger, Sandra

2016-01-01

Studies on the evolution of parental care have focused primarily on the costs and benefits of parental care and the life-history attributes that favour it. However, once care evolves, offspring in some taxa appear to become increasingly dependent on their parents. Although offspring dependency is a central theme in family life, the evolutionary dynamics leading to it are not fully understood. Beetles of the genus Nicrophorus are well known for their elaborate biparental care, including provisioning of their young. By manipulating the occurrence of pre- or post-hatching care, we show that the offspring of three burying beetle species, N. orbicollis, N. pustulatus, and N. vespilloides, show striking variation in their reliance on parental care. Our results demonstrate that this variation within one genus arises through a differential dependency of larvae on parental feeding, but not on pre-hatching care. In N. pustulatus, larvae appear to be nutritionally independent of their parents, but in N. orbicollis, larvae do not survive in the absence of parental feeding. We consider evolutionary scenarios by which nutritional dependency may have evolved, highlighting the role of brood size regulation via infanticide in this genus. PMID:27378180

Aerial radiological survey of the area surrounding the Edwin I. Hatch Nuclear Plant, Baxley, Georgia

International Nuclear Information System (INIS)

Hilton, L.K.

1978-11-01

An airborne radiological survey of a 2146 km 2 area surrounding the Edwin I. Hatch Nuclear Plant was made 28-31 March 1977. Detected radioisotopes, and their associated gamma ray exposure rates, were consistent with that expected from the normal background emitters. Count rates observed at 152 m altitude are converted to equivalent exposure rates at 1 m above the ground, and are presented in the form of an isopleth map. Exposure rates measured with small portable instruments and soil sample analysis showed agreement with the airborne data

The presence of lysylpyridinoline in the hypertrophic cartilage of newly hatched chicks

Science.gov (United States)

Orth, M. W.; Martinez, D. A.; Cook, M. E.; Vailas, A. C.

1993-01-01

The presence of lysylpyridinoline (LP) as a nonreducible cross-link in appreciable quantities has primarily been limited to the mineralized tissues, bone and dentin. However, the results reported here show that LP is not only present in the hypertrophic cartilage of the tibiotarsus isolated from newly hatched broiler chicks, but it is approx. 4-fold as concentrated as hydroxylysylpyridinoline (HP). Bone and articular cartilage surrounding the hypertrophic cartilage do not contain measurable quantities of LP. Purified LP has a fluorescent scan similar to purified HP and literature values, confirming that we indeed were measuring LP. Also, the cartilage lesion produced by immature chondrocytes from birds with tibial dyschondroplasia had LP but the HP:LP ratio was > 1. Thus, the low HP:LP ratio could be a marker for hypertrophic cartilage in avians.

The effects of waterborne uranium on the hatching success, development, and survival of early life stages of zebrafish (Danio rerio)

International Nuclear Information System (INIS)

Bourrachot, Stephanie; Simon, Olivier; Gilbin, Rodolphe

2008-01-01

In this study, we investigated the effects of the radioactive metal uranium (U) on the embryonic development, hatching success, growth rate, and survival of juvenile zebrafish (Danio rerio). We studied the effects of depleted uranium (20-500 μg L -1 of DU), inducing mainly chemical toxicity due to its low specific activity, and the combined effects of chemical and radiological toxicity by using a higher specific activity uranium isotope (20 and 100 μg L -1 of 233 U). Results showed that early life stages are significantly affected by uranium exposure through both chemical and combined (chemical and radiological) toxicity. Experiments showed significant effects of U on hatching success starting at the concentration of 250 μg L -1 of DU, causing a 42% delay in median hatching times relative to control. Furthermore, a reduction of growth (decrease in body length and weight) was observed followed by a high mortality of pro-larvae stage (up to 100% at DU concentrations of 250 μg L -1 upon a 15 day exposure). Bioaccumulation measurements highlighted that U was mainly localised in the chorion but penetrated in the embryo inside eggs at a higher concentration. The effects differed depending on the isotopic composition of the uranium: sublethal defects in the tail detachment process were more pronounced for 233 U than DU exposure, while the presence of 233 U specifically affected embryo development and led to higher mortality rates of the prolarvae. The results from this study showed that the early life stages of zebrafish seems to be more sensitive to uranium contamination than more mature stages, and underline the importance of including pro-larval stages into toxicity tests in order to improve the relevancy for environmental risk assessments

Ocean Warming Enhances Malformations, Premature Hatching, Metabolic Suppression and Oxidative Stress in the Early Life Stages of a Keystone Squid

Science.gov (United States)

Rosa, Rui; Pimentel, Marta S.; Boavida-Portugal, Joana; Teixeira, Tatiana; Trübenbach, Katja; Diniz, Mário

2012-01-01

Background The knowledge about the capacity of organisms’ early life stages to adapt to elevated temperatures is very limited but crucial to understand how marine biota will respond to global warming. Here we provide a comprehensive and integrated view of biological responses to future warming during the early ontogeny of a keystone invertebrate, the squid Loligo vulgaris. Methodology/Principal Findings Recently-spawned egg masses were collected and reared until hatching at present day and projected near future (+2°C) temperatures, to investigate the ability of early stages to undergo thermal acclimation, namely phenotypic altering of morphological, behavioural, biochemical and physiological features. Our findings showed that under the projected near-future warming, the abiotic conditions inside the eggs promoted metabolic suppression, which was followed by premature hatching. Concomitantly, the less developed newborns showed greater incidence of malformations. After hatching, the metabolic burst associated with the transition from an encapsulated embryo to a planktonic stage increased linearly with temperature. However, the greater exposure to environmental stress by the hatchlings seemed to be compensated by physiological mechanisms that reduce the negative effects on fitness. Heat shock proteins (HSP70/HSC70) and antioxidant enzymes activities constituted an integrated stress response to ocean warming in hatchlings (but not in embryos). Conclusions/Significance The stressful abiotic conditions inside eggs are expected to be aggravated under the projected near-future ocean warming, with deleterious effects on embryo survival and growth. Greater feeding challenges and the lower thermal tolerance limits of the hatchlings are strictly connected to high metabolic demands associated with the planktonic life strategy. Yet, we found some evidence that, in the future, the early stages might support higher energy demands by adjusting some cellular functional properties

An endocrine disruptor, bisphenol A, affects development in the protochordate Ciona intestinalis: Hatching rates and swimming behavior alter in a dose-dependent manner

International Nuclear Information System (INIS)

Matsushima, Ayami; Ryan, Kerrianne; Shimohigashi, Yasuyuki; Meinertzhagen, Ian A.

2013-01-01

Bisphenol A (BPA) is widely used industrially to produce polycarbonate plastics and epoxy resins. Numerous studies document the harmful effects caused by low-dose BPA exposure especially on nervous systems and behavior in experimental animals such as mice and rats. Here, we exposed embryos of a model chordate, Ciona intestinalis, to seawater containing BPA to evaluate adverse effects on embryonic development and on the swimming behavior of subsequent larvae. Ciona is ideal because its larva develops rapidly and has few cells. The rate of larval hatching decreased in a dose-dependent manner with exposures to BPA above 3 μM; swimming behavior was also affected in larvae emerging from embryos exposed to 1 μM BPA. Adverse effects were most severe on fertilized eggs exposed to BPA within 7 h post-fertilization. Ciona shares twelve nuclear receptors with mammals, and BPA is proposed to disturb the physiological functions of one or more of these. - Highlights: ► Embryos of Ciona intestinalis were exposed to BPA to evaluate its developmental effects. ► The rate of larval hatching decreased in a dose-dependent manner. ► Swimming behavior was affected in larvae that emerge from embryos exposed to 1 μM BPA. ► Our findings will support a new strategy to analyze the developmental effects induced by BPA. - Exposure of fertilized Ciona embryos to BPA decreased their hatch rate in a dose-dependent manner and led to abnormal larval swimming behavior.

Pengaruh Selang Waktu Peletakkan Terhadap Keberhasilan Penetasan Telur Penyu Hijau (Chelonia mydas L. (Effect of Planting Time on Egg Hatching Success of Green Turtle (Chelonia mydas L.

Directory of Open Access Journals (Sweden)

Edi Wibowo Kushartono

2014-09-01

Full Text Available Salah satu usaha konservasi melindungi Penyu hijau (Chelonia mydas L. yaitu dengan tindakan relokasi dengan memindahkan telur dari sarang alami ke tempat penetasan semi alami. Waktu pemindahan dan peletakan telur yang tepat sangat diperlukan untuk memperoleh daya tetas maksimal. Tujuan penelitian ini untuk mengetahui pengaruh selang waktu peletakan telur Penyu Hijau terhadap keberhasilan penetasannya. Rancangan penelitian adalah Rancangan Acak Kelompok berdasarkan 3 induk yang berbeda dengan perlakuan selang waktu peletakan yaitu 2, 7 dan 12 jam. Pengukuran dan pengamatan kondisi lingkungan dilakukan selama inkubasi. Pengamatan munculnya tukik mulai dilakukan pada hari ke 50 masa inkubasi.  Pembongkaran sarang dilakukan pada hari ke 60 masa inkubasi kemudian dilakukan pembedahan secara manual untuk mengamati telur yang gagal menetas. Hasil menunjukkan bahwa tidak ada pengaruh nyata secara signifikan adanya perbedaan selang waktu peletakan terhadap keberhasilan penetasan dan keberhasilan kemunculan. Namun selang waktu peletakan dengan nilai yang baik ditunjukkan pada 2 jam, dilanjutkan dengan 12 jam dan 7 jam. Kata kunci: penetasan, penyu hijau (Chelonia mydas L., semi alami One of the conservation efforts undertaken to protect the green turtle (C. mydas L. is by relocation of the nest where the eggs are removed from natural to semi-natural hatchery. A right time for the removal and burial of eggs are needed to obtain maximum hatching rate. The purpose of this study is to determine the impact of interval laying period on the hatching success of the green turtle eggs. Randomized block design is used which is based on three different turtles with treatment interval of burying, which is 2, 7, and 12 h. Measurements and observations were made during the environmental conditions of the incubation period. Observations hatchling emergence started on day 50 of incubation. Nest destruction was conducted on the 60th day incubation then eggs that failed to

Effects of in ovo injection of organic trace minerals and post-hatch holding time on broiler performance and bone characteristics

Science.gov (United States)

Effects of the in ovo injection of organic Mn, Zn, and Cu in association with post-hatch (POH) feed and water restriction on the performance and physical-chemical bone parameters of male Ross × Ross 708 broilers were examined. On 17 d of incubation, a total of 1,872 eggs were subjected to in ovo inj...

A novel model of early development in the brine shrimp, Artemia franciscana, and its use in assessing the effects of environmental variables on development, emergence, and hatching.

Science.gov (United States)

Neumeyer, Courtney H; Gerlach, Jamie L; Ruggiero, Kristin M; Covi, Joseph A

2015-03-01

The brine shrimp, Artemia (Crustacea, Anostraca), is a zooplankton that is commonly used in both basic and applied research. Unfortunately, Artemia embryos are often cultured under conditions that alter early development, and reports based on these cultures oversimplify or fail to describe morphological phenotypes. This is due in part to the lack of a comprehensive developmental model that is applicable to observations of live specimens. The objective of this study was to build and test a descriptive model of post-diapause development in Artemia franciscana using observations made with a standard dissecting microscope. The working model presented is the first to comprehensively place all known "abnormal" embryonic and naupliar phenotypes within the context of a classic hatching profile. Contrary to previous reports, embryos and nauplii with aberrant phenotypes often recover and develop normally. Oval prenauplii may emerge as normal prenauplii (E2 stage). A delay of this transition leads to incomplete hatching or direct hatching of first instar larvae with a curved thoracoabdomen. When hatching is incomplete, retained cuticular remnants are shed during the next molt, and a "normal" second instar larva is produced. By differentiating between molting events and gross embryonic patterning in live embryos, this new model facilitates fine time-scale analyses of chemical and environmental impacts on early development. A small increase in salinity within what is commonly believed to be a permissive range (20‰-35‰) produced aberrant morphology by delaying emergence without slowing development. A similar effect was observed by decreasing culture density within a range commonly applied in toxicological studies. These findings clearly demonstrate that morphological data from end-point studies are highly dependent on the time points chosen. An alternate assessment method is proposed, and the potential impact of heavy metals, hexachlorobenzene, Mirex, and cis

Land Cover - Minnesota Land Cover Classification System

Data.gov (United States)

Minnesota Department of Natural Resources — Land cover data set based on the Minnesota Land Cover Classification System (MLCCS) coding scheme. This data was produced using a combination of aerial photograph...

Draft environmental statement: Related to operation of the Edwin I. Hatch Nuclear Plant Unit No. 2, Georgia Power Company: Docket No. 50-366

International Nuclear Information System (INIS)

1977-04-01

The proposed action is the issuance of an operation license to the Georgia Power Company for the startup and operation of the Edwin I. Hatch Nuclear Plant, Unit No. 2 (Docket No. 50-366), located on the Altamaha River in Appling County, approximately 11 miles north from Baxley, Georgia. The information in this Statement represents the second, assessment of the environmental impact associated with the Edwin I. Hatch Nuclear Plant, Unit No. 2, pursuant to the guidelines of the National Environmental Policy Act of 1969 (NEPA) and 10 CFR Part 51 of the Commission's Regulations. After receipt of an application, in 1970, to construct this plant, the staff carried out a review of impact that would occur during the construction and operation of this plant. That evaluation was issued as a Final Environmental Statement in October 1972. As the result of that environmental review, a safety review, an evaluation by the Advisory Committee on Reactor Safeguards, and a public hearing in Baxley, Georgia and Washington, D.C., the AEC (now NRC) issued a permit in December 1972, for the construction of Unit No. 2 of the Edwin I. Hatch Nuclear Plant. As of February 1977, the construction of Unit No. 2 was 70% complete. With a proposed fuel-loading date of April 1978 for Unit No. 2, the applicant has petitioned for license to operate Unit No. 2 and has submitted (July 1975) the required safety and environmental reports to substantiate this petition. 97 refs., 18 figs., 37 tabs

Effect of electron irradiation in hatching eggs experimentally inoculated with salmonella enteriditis, on hatch ability and broiler performance; Efecto de la irradiacion con electrones en huevos fertiles inoculados experimentalmente con salmonella enteriditis sobre la incubabilidad y desarrollo productivo

Energy Technology Data Exchange (ETDEWEB)

Castaneda S, M P

1996-12-31

The effect of four doses of electrons irradaition on bacteriologic population in hatching egg following experimental shell contamination with Salmonella enteriditis phage type 13 was investigated. Fresh, whole, intact raw eggs were inoculated with 10{sup 9} Colony-Forming Units of Salmonella enteriditis, eggs were irradiated with a beam electron source at either: 0.5, 1, 2 and 3 KGy. The bacteriologic evaluation was made with Gentry`s and Williams` technic. After the irradiation the groups were taken to commercial hatchery and were incubated in satndards conditions. The bacteriologic evaluation of the shell showed a significant 2.8 log reduction on the group of eggs that were irradiated with 1 KGy as compared with 0.5 KGy doses group and control group (P<0.05). A negative correlation (r=-0.93) between irradiation doses and CFU (P<0.05) was also observed. Bacteriologic evaluation of the internal shell membrane exhibited a highly significant inactivation (P<0.01) of S. enteriditis of 100% in the group of eggs irradiated at 2 and 3 kGy. A high negative correlation (r=-0.90) between irradiation doses and samples of internal structures (P<0.05) was observed. The results obtained suggested that the electrons irradiation may be use like a control system of salmonelosis on egg and like desinfection system on hatching eggs because it did not cause any effect on hatchability and broiler performance. (Author).

Influence of natural inshore and offshore thermal regimes on egg development and time of hatch in American lobsters, Homarus americanus.

Science.gov (United States)

Goldstein, Jason S; Watson, Winsor H

2015-02-01

Some egg-bearing (ovigerous) American lobsters (Homarus americanus) make seasonal inshore-to-offshore movements, subjecting their eggs to different thermal regimes than those of eggs carried by lobsters that do not make these movements. Our goal was to determine if differences in thermal regimes influence the rate of egg development and the subsequent time of hatch. We subjected ovigerous lobsters to typical inshore or offshore water temperatures from September to August in the laboratory (n=8 inshore and 8 offshore, each year) and in the field (n=8 each, inshore and offshore), over 2 successive years. Although the rate of egg development did not differ significantly between treatments in the fall (P∼0.570), eggs exposed to inshore thermal regimes developed faster in the spring (Plobsters exposed to offshore thermal regimes accumulated more GDD in the winter than did eggs carried by inshore lobsters, while eggs exposed to inshore temperatures acquired them more rapidly in the spring. Results suggest that seasonal movements of ovigerous lobsters influence the time and location of hatching, and thus the transport and recruitment of larvae to coastal and offshore locations. © 2015 Marine Biological Laboratory.

Drug discovery and the impact of the safe harbor provision of the Hatch- Waxman Act.

Science.gov (United States)

Goodson, Susanne H

2010-01-01

Many facets of drug discovery involve the use of patented materials and methods, subjecting the researcher to potential liability from infringement of the underlying patents. Enacted in 1984, the Hatch-Waxman Act established a “safe harbor” for activities that would otherwise constitute infringement of a patented invention, if those activities were “solely for uses reasonably related to the development and submission of information under a Federal law which regulates the manufacture, use, or sale of drugs or veterinary biological products”. This article examines the major court decisions interpreting the scope of the safe harbor and their application to various activities in drug development.

When Eggs Don't Hatch. The Benefits of the Sterile Insect Technique

International Nuclear Information System (INIS)

Kilian, Lizette

2012-01-01

Insect pests, such as the medfly, tsetse flies and carob moth can devastate crops and infect herds, causing severe economic hardship. To suppress the insect pest population and protect their livestock and crops, farmers usually use large quantities of pesticides. However, these pesticides are expensive, a risk to public health and cause environmental damage. Another technique, however, can reduce the insect pest population using natural means that do not require toxic chemicals: the sterile insect technique, or SIT. When female insect pests mate with male partners that have been radiation sterilized, the insemination produces eggs that cannot hatch. Since mating does not produce offspring, the insect population decreases naturally. The pest population can be suppressed with little or no use of pesticides. With the help of the IAEA, farmers have applied SIT successfully in over 20 countries on five continents, for over 15 insect species worldwide.

Shell Properties, Water Vapor Loss, and Hatching Success of Eggs from a Rain Forest Population of the Pearly-eyed Thrasher (Margarops fuscatus)

Science.gov (United States)

WAYNE J. ARENDT

2005-01-01

I calculated various shell properties, water vapor loss, and hatching success of eggs of the Pearly-eyed Thrasher (Margarops fuscatus) using measurements obtained during a long-term study in the Luquillo Mountains, Puerto Rico. Empirical results were comparable to standard reference formulae, demonstrating that published formulae can be used with confidence by field...

Effect of in ovo supplementation of nano forms of zinc, copper, and selenium on post-hatch performance of broiler chicken

Directory of Open Access Journals (Sweden)

P. Patric Joshua

2016-03-01

Full Text Available Background and Aim: Nanoparticles can bypass conventional physiological ways of nutrient distribution and transport across tissue and cell membranes, as well as protect compounds against destruction prior to reaching their targets. In ovo administration of nanoparticles, may be seen as a new method of nano-nutrition, providing embryos with an additional quantity of nutrients. The aim of the study is to examine the effect of in ovo supplementation of nano forms of zinc, copper and selenium on the hatchability and post hatch performance of broiler chicken. Materials and Methods: Nano form of zinc at 20, 40, 60 and 80 μg/egg, nano form of copper at 4, 8, 12 and 16 μg/egg and nano form of selenium at 0.075, 0.15, 0.225 and 0.3 μg/egg were in ovo supplemented (18th day incubation, amniotic route in fertile broiler eggs. Control group in ovo fed with normal saline alone was also maintained. Each treatment had thirty replicates. Parameters such as hatchability, hatch weight and post hatch performance were studied. Results: In ovo feeding of nano minerals were not harmful to the developing embryo and did not influence the hatchability. Significantly (p<0.05 best feed efficiency for nano forms of zinc (2.16, copper (2.46 and selenium (2.51 were observed, when 40, 4 and 0.225 μg/egg respectively were in ovo supplemented. Except in nano form of copper at 12 μg per egg which had significantly (p<0.05 highest breast muscle percentage there was no distinct trend to indicate that dressing percentage or breast muscle yield was influenced in other treatments. Conclusion: Nano forms of zinc, copper and selenium can be prepared at laboratory conditions. In ovo feeding of nano forms of zinc, copper and selenium at 18th day of incubation through amniotic route does not harm the developing embryo, does not affect hatchability.

The effect of egg versus seston quality on hatching success, naupliar metabolism and survival of Calanus finmarchicus in mesocosms dominated by Phaeocystis and diatoms

DEFF Research Database (Denmark)

Koski, Marja; Yebra, L.; Dutz, Jörg

2012-01-01

We studied the effect of a developing Skeletonema marinoi/Phaeocystis spp. bloom on Calanus finmarchicus hatching success, early naupliar survival and metabolism. Our focus was (1) on the development of reproductive rates during a bloom initiation, peak and decline in relation to the production o...

Systems Analysis of Remote Piloting/Robotics Technology Applicable to Assault Rafts.

Science.gov (United States)

1982-01-01

LTOG 3.936 m n Driver Position Driver is only member of crew seated under armor - seated in front leftI of hull - 3 M17 periscopes - single piece...hatch cover. Vision Data Summary I.D - 3P; H - 82.5* to 165* V - 110 to 220 SC - Is not under armor ; therefore has freedom of vision. Mobility Information... under armor - seated in front left * of hull - 3 Ml7 periscopes - single piece hatch cover. 4Vision Data Summary SD - 3P; H - 82.50 to 1650 V - 110 to

Mobile Incubation in Waved Albatross (Phoebastria irrorata: Associated Hatching Failure and Artificial Mitigation

Directory of Open Access Journals (Sweden)

Jill A. Awkerman

2005-12-01

Full Text Available Waved albatrosses often relocate their eggs during incubation by placing the egg between the tarsi and shuffling forward. This behavior frequently results in eggs becoming lodged between rocks, accounting for at least 10%, and perhaps as much as 80%, of breeding failures. Because albatross populations worldwide are currently threatened, artificial means of augmenting reproductive success may be necessary to mitigate losses caused by anthropogenic effects. We characterize the frequency and extent of egg movement; test several hypotheses related to microhabitat, timing, and incubation location to explain the behavior; and investigate the utility of repositioning lodged eggs in a location in which breeding birds might resume incubation. Egg rescue increased both the likelihood of continued incubation as well as the hatching rate in our experiment, and provides an efficient, low-cost management option for this species.

National Land Cover Database (NLCD) Land Cover Collection

Data.gov (United States)

U.S. Geological Survey, Department of the Interior — The National Land Cover Database (NLCD) Land Cover Collection is produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC)...

Maternal thyroid hormones enhance hatching success but decrease nestling body mass in the rock pigeon (Columba livia).

Science.gov (United States)

Hsu, Bin-Yan; Dijkstra, Cor; Darras, Veerle M; de Vries, Bonnie; Groothuis, Ton G G

2017-01-01

Thyroid hormones (THs) - triiodothyronine (T3) and thyroxine (T4) - are essential for embryonic development in vertebrates. All vertebrate embryos are exposed to THs from maternal origin. As maternal TH levels are known to be essential to embryonic development, the natural variation of maternal THs probably represents a pathway of maternal effects that can modify offspring phenotype. However, potential fitness consequences of variation of maternal TH exposure within the normal physiological range and without confounding effects of the mother have never been experimentally investigated. We experimentally manipulated the levels of yolk T3 and T4 within the physiological range in a species in which the embryo develops outside the mother's body, the Rock Pigeon (Columba livia) eggs. Making use of the natural difference of yolk testosterone between the two eggs of pigeon clutches, we were also able to investigate the potential interaction between THs and testosterone. Elevated yolk TH levels enhanced embryonic development and hatching success, and reduced body mass but not tarsus length between day 14 and fledging. The yolk hormones increased plasma T4 concentrations in females but reduced it in males, in line with the effect on metabolic rate at hatching. Plasma concentrations of T3 and testosterone were not significantly affected. The effects of treatment did not differ between eggs with high or low testosterone levels. Our data indicate that natural variation in maternal yolk TH levels affects offspring phenotype and embryonic survival, potentially influencing maternal and chick fitness. Copyright © 2016 Elsevier Inc. All rights reserved.

Measurement of dose rates and Monte Carlo analysis of neutrons in a spent-fuel shipping vessel

International Nuclear Information System (INIS)

Ueki, K.; Namito, Y.; Fuse, T.

1986-01-01

On-board experiments were carried out in a spent-fuel shipping vessel, the Pacific Swan, in which 13 casks of TN-12A and Excellox 3 were loaded in five holds, and neutron and gamma-ray dose rates were measured on the hatch covers of the holds. Before shipping those casks, dose rates were also measured on the cask surfaces, one by one, to eliminate radiation from other casks. The Monte Carlo coupling technique was employed successfully to analyze the measured neutron dose rate distributions in the spent-fuel shipping vessel. Through this study, the Monte Carlo coupling code system, MORSE-CG/CASK-VESSEL, on which the MORSE-CG code was based, was established. The agreement between the measured and the calculated neutron dose rates on the TN-12A cask surface was quite satisfactory. The calculated neutron dose rates agreed with the measured values within a factor of 1.5 on the hold 3 hatch cover and within a factor of 2 on the hold 5 hatch cover in which the concrete shield was fixed in the Pacific Swan

Joint Effect of Solar UVB and Heat Stress on the Seasonal Change of Egg Hatching Success in the Herbivorous False Spider Mite (Acari: Tenuipalpidae).

Science.gov (United States)

Sudo, M; Osakabe, M

2015-12-01

Seasonal population dynamics of an herbivorous mite has been documented in terms of the relationship between thermoresponses and temporal biological factors such as resource availability or predation risk. Although recent studies emphasize the deleterious effects of solar ultraviolet-B (UVB; 280-320 nm wavelengths) radiation on plant-dwelling mites, how UVB affects mite population remains largely unknown. On a wild shrub Viburnum erosum var. punctatum in Kyoto, an herbivorous false spider mite, Brevipalpus obovatus Donnadieu, occurs only in autumn. Females of this species lay one-third of their eggs on upper leaf surfaces. Oviposition on upper surfaces is beneficial for avoiding predation by phytoseiids, but exposes eggs to solar UVB and heat stress. To test the hypothesis that the seasonal occurrence of this mite is determined by interactions between solar UVB radiation and temperature, we examined variation in egg hatching success under near-ambient and UV-attenuated sunlight conditions from spring to autumn. The UV-attenuation significantly improved hatching success. However, most eggs died under heat stress regardless of UV treatments in July and August. We established a deterministic heat stress-cumulative UVB dose-egg hatching success response model, which we applied to meteorological data. The model analyses illustrated lower and higher survivability peaks in late May and October, respectively, which partly corresponded to data for annual field occurrence, indicating the importance of solar UVB radiation and heat stress as determinants of the seasonal occurrence of this mite. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Hatching phenology and voltinism of Heterocypris barbara (Crustacea: Ostracoda from Lampedusa (Sicily, Italy

Directory of Open Access Journals (Sweden)

Valeria Rossi

2013-04-01

Full Text Available The persistence of crustacean populations in ephemeral ponds requires appropriate adaptations in life history strategies (e.g. in hatching phenology. Organisms take advantage of pond filling when it occurs and hedge their bets for the possibility to complete one or more life cycles or to produce resting stages that ensure that the population will not go extinct. We carried out laboratory experiments to investigate the dynamics of a sexual population of Heterocypris barbara from a vernal pool in Lampedusa Island (Sicily. Experimental organisms were obtained hydrating sediments from Aria Rossa temporary pond. Recruitment from resting eggs, voltinism, mean body size and sex ratio were observed in microcosms at different conductivities (high 2.0-2.7 mS cm-1, intermediate 1.0-1.1 mS cm-1 and low 0.5-0.6 mS cm-1. Microcosms were kept in laboratory controlled conditions: constant (24°C 12:12 L:D and 16°C 10:14 L:D photoperiod or fluctuating thermal regimes. The experiment lasted 7 months. Resting and non-resting egg production and up to a bivoltine life cycle were observed. Recruitment events from egg bank and voltinism varied by thermal regime and conductivity. A prolonged recruitment phase occurred in conditions that could be considered a proxy of a rainy season (16°C, 10:14 L:D and low conductivity or of long hydroperiods (spring thermal fluctuating regime and intermediate conductivity. At 24°C, age at reproduction of females from resting eggs almost doubled at low conductivity (in comparison with high conductivity. Low conductivity also reduced hatching time of resting eggs while it increased development time and age at maturity. In thermal fluctuating regime, degree-days to reproduction were about double than at constant 24°C. Males, observed in all microcosms, reached maturity faster and had a shorter life span than females. Males initially outnumbered females, but later in the experiments females became dominant. We also evaluated the

Landfill Top Covers

DEFF Research Database (Denmark)

Scheutz, Charlotte; Kjeldsen, Peter

2011-01-01

The purpose of the final cover of a landfill is to contain the waste and to provide for a physical separation between the waste and the environment for protection of public health. Most landfill covers are designed with the primary goal to reduce or prevent infiltration of precipitation...... into the landfill in order to minimize leachate generation. In addition the cover also has to control the release of gases produced in the landfill so the gas can be ventilated, collected and utilized, or oxidized in situ. The landfill cover should also minimize erosion and support vegetation. Finally the cover...... is landscaped in order to fit into the surrounding area/environment or meet specific plans for the final use of the landfill. To fulfill the above listed requirements landfill covers are often multicomponent systems which are placed directly on top of the waste. The top cover may be placed immediately after...

Exposure to waterborne Cu inhibits cutaneous Na⁺ uptake in post-hatch larval rainbow trout (Oncorhynchus mykiss).

Science.gov (United States)

Zimmer, Alex M; Brauner, Colin J; Wood, Chris M

2014-05-01

In freshwater rainbow trout (Oncorhynchus mykiss), two common responses to acute waterborne copper (Cu) exposure are reductions in ammonia excretion and Na(+) uptake at the gills, with the latter representing the likely lethal mechanism of action for Cu in adult fish. Larval fish, however, lack a functional gill following hatch and rely predominantly on cutaneous exchange, yet represent the most Cu-sensitive life stage. It is not known if Cu toxicity in larval fish occurs via the skin or gills. The present study utilized divided chambers to assess cutaneous and branchial Cu toxicity over larval development, using disruptions in ammonia excretion (Jamm) and Na(+) uptake (Jin(Na)) as toxicological endpoints. Early in development (early; 3 days post-hatch; dph), approximately 95% of Jamm and 78% of Jin(Na) occurred cutaneously, while in the late developmental stage (late; 25 dph), the gills were the dominant site of exchange (83 and 87% of Jamm and Jin(Na), respectively). Exposure to 50 μg/l Cu led to a 49% inhibition of Jamm in the late developmental stage only, while in the early and middle developmental (mid; 17 dph) stages, Cu had no effect on Jamm. Jin(Na), however, was significantly inhibited by Cu exposure at the early (53% reduction) and late (47% reduction) stages. Inhibition at the early stage of development was mediated by a reduction in cutaneous uptake, representing the first evidence of cutaneous metal toxicity in an intact aquatic organism. The inhibitions of both Jamm and Jin(Na) in the late developmental stage occurred via a reduction in branchial exchange only. The differential responses of the skin and gills to Cu exposure suggest that the mechanisms of Jamm and Jin(Na) and/or Cu toxicity differ between these tissues. Exposure to 20μg/l Cu revealed that Jamm is the more Cu-sensitive process. The results presented here have important implications in predicting metal toxicity in larval fish. The Biotic Ligand Model (BLM) is currently used to predict

Evapotranspiration (ET) covers.

Science.gov (United States)

Rock, Steve; Myers, Bill; Fiedler, Linda

2012-01-01

Evapotranspiration (ET) cover systems are increasingly being used at municipal solid waste (MSW) landfills, hazardous waste landfills, at industrial monofills, and at mine sites. Conventional cover systems use materials with low hydraulic permeability (barrier layers) to minimize the downward migration of water from the surface to the waste (percolation), ET cover systems use water balance components to minimize percolation. These cover systems rely on soil to capture and store precipitation until it is either transpired through vegetation or evaporated from the soil surface. Compared to conventional membrane or compacted clay cover systems, ET cover systems are expected to cost less to construct. They are often aesthetic because they employ naturalized vegetation, require less maintenance once the vegetative system is established, including eliminating mowing, and may require fewer repairs than a barrier system. All cover systems should consider the goals of the cover in terms of protectiveness, including the pathways of risk from contained material, the lifecycle of the containment system. The containment system needs to be protective of direct contact of people and animals with the waste, prevent surface and groundwater water pollution, and minimize release of airborne contaminants. While most containment strategies have been based on the dry tomb strategy of keeping waste dry, there are some sites where adding or allowing moisture to help decompose organic waste is the current plan. ET covers may work well in places where complete exclusion of precipitation is not needed. The U.S. EPA Alternative Cover Assessment Program (ACAP), USDOE, the Nuclear Regulatory Commission, and others have researched ET cover design and efficacy, including the history of their use, general considerations in their design, performance, monitoring, cost, current status, limitations on their use, and project specific examples. An on-line database has been developed with information

Land Cover

Data.gov (United States)

Kansas Data Access and Support Center — The Land Cover database depicts 10 general land cover classes for the State of Kansas. The database was compiled from a digital classification of Landsat Thematic...

Metal stress in zooplankton diapause production: post-hatching response.

Science.gov (United States)

Aránguiz-Acuña, Adriana; Pérez-Portilla, Pablo

2017-04-01

Aquatic organisms commonly respond to harsh conditions by forming diapausing stages, which enable populations to survive adverse periods forming egg banks. Production of diapausing eggs is frequently observed in monogonont rotifers, previously changing from asexual to partial sexual reproduction (mixis). In despite that zooplankton are frequently used in ecotoxicological assessment because of their sensitivity to various toxicants and their important role in the ecosystems, toxicity evaluations often consider the directly exposed population produced by parthenogenetic reproduction, exclusively. We assessed experimentally effects of exposure to metals on mixis delay and fitness of hatchlings of the rotifer Brachionus plicatilis obtained from a brackish water lagoon with high metal content, especially copper. We show that sub-lethal concentrations of copper affected traits related to sexual reproduction and diapausing egg production in the rotifer. Copper addition did not delay the start of mixis, suggesting that rapid initiation of mixis is promoted in risky environments, according to the hypothesis of mixis as an escape strategy. Higher investment in mixis was obtained when individuals were exposed to metal. Addition of copper negatively affected the hatching success of diapausing eggs and performance of hatchlings. Nevertheless, these effects were greater for individuals formed in non-metal conditions, suggesting an adaptive advantage of populations from natural sediments exposed to copper. These results highlight the ecological and evolutionary consequences of the presence of metals in freshwater environments by modulating diapause adaptive efficacy and the selective process in egg banks.

Face recognition in newly hatched chicks at the onset of vision.

Science.gov (United States)

Wood, Samantha M W; Wood, Justin N

2015-04-01

How does face recognition emerge in the newborn brain? To address this question, we used an automated controlled-rearing method with a newborn animal model: the domestic chick (Gallus gallus). This automated method allowed us to examine chicks' face recognition abilities at the onset of both face experience and object experience. In the first week of life, newly hatched chicks were raised in controlled-rearing chambers that contained no objects other than a single virtual human face. In the second week of life, we used an automated forced-choice testing procedure to examine whether chicks could distinguish that familiar face from a variety of unfamiliar faces. Chicks successfully distinguished the familiar face from most of the unfamiliar faces-for example, chicks were sensitive to changes in the face's age, gender, and orientation (upright vs. inverted). Thus, chicks can build an accurate representation of the first face they see in their life. These results show that the initial state of face recognition is surprisingly powerful: Newborn visual systems can begin encoding and recognizing faces at the onset of vision. (c) 2015 APA, all rights reserved).

78 FR 20888 - Foreign-Trade Zone (FTZ) 161-Sedgwick County, Kansas; Notification of Proposed Production...

Science.gov (United States)

2013-04-08

...- corrosion coatings; plastic tubes/washers/hoses/seals/sheets/tape/bags/ containers; bushings; funnels...; covers; gaskets; labels; fasteners; bolt extenders; springs; rings; bushings; flanges; hatches; supports...; filters; copper pipes/adapters/fasteners/reducers; aluminum plates/ flanges/covers; locks and locksets...

Embryos in the fast lane: high-temperature heart rates of turtles decline after hatching.

Directory of Open Access Journals (Sweden)

Wei-Guo Du

Full Text Available In ectotherms such as turtles, the relationship between cardiovascular function and temperature may be subject to different selective pressures in different life-history stages. Because embryos benefit by developing as rapidly as possible, and can "afford" to expend energy to do so (because they have access to the yolk for nutrition, they benefit from rapid heart (and thus, developmental rates. In contrast, hatchlings do not have a guaranteed food supply, and maximal growth rates may not enhance fitness--and so, we might expect a lower heart rate, especially at high temperatures where metabolic costs are greatest. Our data on two species of emydid turtles, Chrysemys picta, and Graptemys pseudogeographica kohnii, support these predictions. Heart rates of embryos and hatchlings were similar at low temperatures, but heart rates at higher temperatures were much greater before than after hatching.

Interrelationships between soil cover and plant cover depending on land use

Directory of Open Access Journals (Sweden)

Tiina Köster

2013-05-01

Full Text Available Interrelationships between soil cover and plant cover of normally developed (or postlithogenic mineral soils are analysed on the basis of four sampling soil groups. The four-link pedo-ecological sequence of analysed soils, rendzinas → brown soils → pseudopodzolic soils → gley-podzols, forms a representative cross section in relation to the normal mineral soils of Estonia. All groups differ substantially from each other in terms of soil properties (calcareousness, acidity, nutrition conditions, profile fabric and humus cover. The primary tasks of the research were (1 to elucidate the main pedo-ecological characteristics of the four soil groups and their suitability for plant cover, (2 to evaluate comparatively soils in terms of productivity, sustainability, biodiversity and environmental protection ability and (3 to analyse possibilities for ecologically sound matching of soil cover with suitable plant cover. On the basis of the same material, the influence of land-use change on humus cover (epipedon fabric, properties of the entire soil cover and soil–plant interrelationship were also analysed. An ecosystem approach enables us to observe particularities caused by specific properties of a soil type (species, variety in biological turnover and in the formation of biodiversity.

Watching sexy displays improves hatching success and offspring growth through maternal allocation.

Science.gov (United States)

Loyau, Adeline; Lacroix, Frédéric

2010-11-22

Male attractiveness can have tremendous effects on the fitness of his offspring via good genes, but also via enhanced maternal allocation of resources. Yet the proximate mechanisms influencing differential maternal allocation in relation to male sexiness are poorly known. Here, we studied the importance of visual stimulation for maternal allocation in the Houbara bustard, a vulnerable bird species bred in captivity to support wild populations. Artificial insemination allowed controlling for potential confounding factors, such as a male's territory quality, social interactions or sperm quality/quantity, probably linked to mate attractiveness. We show that artificially inseminated females stimulated by highly displaying males increased their hatching success, owing to increased fertilization success. The females also increased the allocation of maternal androgens in their eggs, leading to an increase of circulating testosterone and growth rate in chicks. Hence, visual stimulation of the females can promote differential maternal allocation and favour offspring fitness. Our results further suggest that using artificial insemination for species conservation without appropriate stimulation of the breeding females probably has negative impacts on their breeding performance and therefore on population viability.

Successful hatching from eggs carried by females and naturally removed from incubant males in Belostoma spp. water bugs (Heteroptera: Belostomatidae

Directory of Open Access Journals (Sweden)

Ana Lía Estévez

2006-06-01

Full Text Available Within Belostomatinae water bug species (Heteroptera, Belostomatidae it has been hitherto believed that the completion of embryonic development is successful only if eggs are incubated on male hemelytra. Nevertheless, we found egg successful hatching from a back- brooding Belostoma elegans (Mayr and B. micantulum (Stål females, as well as from fertilized eggs kicked off from four back-brooder B. elegans males. One "encumbered" B. elongatum Montandon female was also recorded, but eggs did not hatch after she removed them. Rev. Biol. Trop. 54(2: 515-517. Epub 2006 Jun 01.Se considera que el desarrollo embrionario y la emergencia de las ninfas de las especies de Belostomatinae (Heteroptera, Belostomatidae se cumplen con éxito si los huevos son incubados sobre el espacio dorsal de machos adultos. No obstante, hemos registrado eclosiones exitosas a partir de dos hembras grávidas portando huevos sobre su dorso; una de ellas de la especie Belostoma elegans (Mayr, la otra de B. micantulum (Stål. Se registra la eclosión de huevos, previamente removidos del área de postura por los propios machos incubantes de B. elegans (N=4 y la presencia de una hembra de B. elongatum Montandon, portando huevos sobre sus hemiélitros, los cuales no eclosionaron después de haber sido removidos por la propia hembra.

Antimicrobial resistance of Escherichia coli isolated in newly-hatched chickens and effect of amoxicillin treatment during their growth.

Science.gov (United States)

Jiménez-Belenguer, Ana; Doménech, Eva; Villagrá, Arantxa; Fenollar, Alejandro; Ferrús, Maria Antonia

2016-08-01

The use of antimicrobials in food animals is the major determinant for the propagation of resistant bacteria in the animal reservoir. However, other factors may also play a part, and in particular vertical spread between the generations has been suggested to be an important transmission pathway. The objective of this paper was to determine the resistance patterns of Escherichia coli isolated from newly-hatched chickens as well as to study the antibiotic pressure effect when amoxicillin was administered during their growing period. With this aim, meconium from 22 one-day-old Ross chickens was analysed. In addition, during their growth period, amoxicillin treatments at days 7, 21 and 35 were carried out. Results showed a high number of E. coli-resistant strains were isolated from the treated one-day-old chickens, and were the highest for β-lactams group, followed by quinolone and tetracyclines. After treatment with amoxicillin, the highest percentage of resistances were detected for this antibiotic compared to the others analysed, with significant differences in resistance percentages between control and treated broilers detected in relation to ampicillin, cephalothin, streptomycin, kanamycin, gentamicin, chloramphenicol and tetracycline. Differences in resistances to ciprofloxacin and nalidixic acid between control and treated animals were not observed and there was lack of resistance for amikacin and ceftriaxone. These results suggest the possibility of vertical transmission of resistant strains to newly-hatched chicks from parent flocks, and seem to indicate that the treatment with amoxicillin increased the resistance of E. coli to other antibiotics.

Technical evaluation of RETS-required reports for the Edwin I. Hatch Nuclear Plant, Units 1 and 2

International Nuclear Information System (INIS)

Young, T.E.; Magleby, E.H.

1985-01-01

A review of the reports required by federal regulations and the plant-specific Radiological Effluent Technical Specifications (RETS) for operations conducted during 1983 was performed. The periodic reports reviewed for the Edwin I. Hatch Nuclear Plant were the Annual Radiological Environmental Operating Report for 1983 and the Semiannual Radioactive Effluent Release Reports for 1983. The principal review guidelines were the plant's specific RETS, NUREG-0133, ''Preparation of Radiological Effluent Technical Specifications for Nuclear Power Plants'', and NRC Guidance on the Review of the Process Control Programs. The Licensee's submitted reports were found to be reasonably complete and consistent with the review guidelines. 7 refs

InGaAs Quantum Dots on Cross-Hatch Patterns as a Host for Diluted Magnetic Semiconductor Medium

Directory of Open Access Journals (Sweden)

Teeravat Limwongse

2013-01-01

Full Text Available Storage density on magnetic medium is increasing at an exponential rate. The magnetic region that stores one bit of information is correspondingly decreasing in size and will ultimately reach quantum dimensions. Magnetic quantum dots (QDs can be grown using semiconductor as a host and magnetic constituents added to give them magnetic properties. Our results show how molecular beam epitaxy and, particularly, lattice-mismatched heteroepitaxy can be used to form laterally aligned, high-density semiconducting host in a single growth run without any use of lithography or etching. Representative results of how semiconductor QD hosts arrange themselves on various stripes and cross-hatch patterns are reported.

Silicone covered vs. Non- covered endotracheal self expandable metallic stent: An experimental study

Energy Technology Data Exchange (ETDEWEB)

Do, Young Soo; Lee, Byung Hee; Kim, Soo Ah; Kim, Kie Hwan; Chin, Soo Yil; Cho, Kyung Ja; Cho, Dae Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

1994-10-15

To evaluate pathologic changes of the trachea and the lung after insertion of silicone covered and non covered Gianturco stent in the trachea of dog. Silicone covered(covered) and non covered(bare) Gianturco stent, six in each, were inserted into the tracheal lumen of six consecutive dogs. After 1-10 weeks observation, the dogs were sacrificed and their tracheas and lungs were examined grossly and histopathologically. Serial chest radiographs were performed to evaluate pneumonia and stent migration every 3-5 days. Pneumonia was observed in one of bare stent group and five of covered stent group. Stent migration was noted in three of covered stent group. In bare stent group, the epithelium of the trachea was markedly thickened by hyperplasia and stent was covered by granulation tissue from 6 weeks after stent insertion. Inflammation was focal at contact site between the stent and the trachea. In covered stent group, the epithelium was denuded at multiple areas and there were multifocal squamous metaplasia of the mucosa. Inflammatory reaction of the trachea was diffuse. Inflammatory reaction was more severe and stent migration was more frequent in covered stent group. The use of covered stent in the trachea should be studied further.

Effects of ocean acidification on hatch size and larval growth of walleye pollock (Theragra chalcogramma) from laboratory experiment studies from 2010-03-01 to 2011-05-31 (NODC Accession 0125007)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains laboratory experiment data that were collected to examine the effects of ocean acidification on hatch size and larval growth of...

Branched polynomial covering maps

DEFF Research Database (Denmark)

Hansen, Vagn Lundsgaard

2002-01-01

A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch ...... set. Particular studies are made of branched polynomial covering maps arising from Riemann surfaces and from knots in the 3-sphere. (C) 2001 Elsevier Science B.V. All rights reserved.......A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...

Mekong Land Cover Dasboard: Regional Land Cover Mointoring Systems

Science.gov (United States)

Saah, D. S.; Towashiraporn, P.; Aekakkararungroj, A.; Phongsapan, K.; Triepke, J.; Maus, P.; Tenneson, K.; Cutter, P. G.; Ganz, D.; Anderson, E.

2016-12-01

SERVIR-Mekong, a USAID-NASA partnership, helps decision makers in the Lower Mekong Region utilize GIS and Remote Sensing information to inform climate related activities. In 2015, SERVIR-Mekong conducted a geospatial needs assessment for the Lower Mekong countries which included individual country consultations. The team found that many countries were dependent on land cover and land use maps for land resource planning, quantifying ecosystem services, including resilience to climate change, biodiversity conservation, and other critical social issues. Many of the Lower Mekong countries have developed national scale land cover maps derived in part from remote sensing products and geospatial technologies. However, updates are infrequent and classification systems do not always meet the needs of key user groups. In addition, data products stop at political boundaries and are often not accessible making the data unusable across country boundaries and with resource management partners. Many of these countries rely on global land cover products to fill the gaps of their national efforts, compromising consistency between data and policies. These gaps in national efforts can be filled by a flexible regional land cover monitoring system that is co-developed by regional partners with the specific intention of meeting national transboundary needs, for example including consistent forest definitions in transboundary watersheds. Based on these facts, key regional stakeholders identified a need for a land cover monitoring system that will produce frequent, high quality land cover maps using a consistent regional classification scheme that is compatible with national country needs. SERVIR-Mekong is currently developing a solution that leverages recent developments in remote sensing science and technology, such as Google Earth Engine (GEE), and working together with production partners to develop a system that will use a common set of input data sources to generate high

Egg production and hatching success of Calanus chilensis and Acartia tonsa in the northern Chile upwelling zone (23°S), Humboldt Current System

Science.gov (United States)

Ruz, Paula M.; Hidalgo, Pamela; Yáñez, Sonia; Escribano, Rubén; Keister, Julie E.

2015-08-01

Oxygen Minimum Zones (OMZ's) are expanding and intensifying as result of climate change, affecting Eastern Boundary Upwelling Systems. Local effects of vertical movements of OMZ's that result from changes in upwelling intensity could reduce or expand the oxygenated surface layer that most zooplanktonic species inhabit in coastal areas. Using the copepods Calanus chilensis and Acartia tonsa as model organisms, an experimental test of the impact of different dissolved oxygen (DO) concentrations (between 0.5 and 5 ml L- 1) on egg production and hatching success was carried out and compared with field estimations of egg production, female and egg abundance in Mejillones Bay (23°S). Abundance of C. chilensis was highly variability and no consistent pattern in egg production and hatching success was found across DO levels, whereas A. tonsa egg production had maximum values between 2.6 and 4.7 ml O2 L- 1 and hatching success was positively correlated with DO (r = 0.75). In the field, temperature was the main factor controlling the dynamics of both species, while Chl-a and DO were also correlated with C. chilensis and A. tonsa, respectively. Principal Component Analysis showed that abundances of both copepods were controlled by temperature, stratification, OMZ depth, and Ekman transport, which together explained more than 70% of the total variance and were the main factors that modulated the populations of C. chilensis and A. tonsa in the upwelling zone of northern Chile (23°S). The differential responses of C. chilensis and A. tonsa to changes in DO concentrations associated with vertical movements of the OMZ suggest that C. chilensis may be better adapted to hypoxic conditions than A. tonsa, however both species are successful and persistent all year-round. We suggest that physiological responses of copepods could be used to evaluate population dynamics affected by the shoaling of OMZ's and the repercussions to trophic food webs of eastern boundary current systems.

Land cover mapping of North and Central America—Global Land Cover 2000

Science.gov (United States)

Latifovic, Rasim; Zhu, Zhi-Liang

2004-01-01

The Land Cover Map of North and Central America for the year 2000 (GLC 2000-NCA), prepared by NRCan/CCRS and USGS/EROS Data Centre (EDC) as a regional component of the Global Land Cover 2000 project, is the subject of this paper. A new mapping approach for transforming satellite observations acquired by the SPOT4/VGTETATION (VGT) sensor into land cover information is outlined. The procedure includes: (1) conversion of daily data into 10-day composite; (2) post-seasonal correction and refinement of apparent surface reflectance in 10-day composite images; and (3) extraction of land cover information from the composite images. The pre-processing and mosaicking techniques developed and used in this study proved to be very effective in removing cloud contamination, BRDF effects, and noise in Short Wave Infra-Red (SWIR). The GLC 2000-NCA land cover map is provided as a regional product with 28 land cover classes based on modified Federal Geographic Data Committee/Vegetation Classification Standard (FGDC NVCS) classification system, and as part of a global product with 22 land cover classes based on Land Cover Classification System (LCCS) of the Food and Agriculture Organisation. The map was compared on both areal and per-pixel bases over North and Central America to the International Geosphere–Biosphere Programme (IGBP) global land cover classification, the University of Maryland global land cover classification (UMd) and the Moderate Resolution Imaging Spectroradiometer (MODIS) Global land cover classification produced by Boston University (BU). There was good agreement (79%) on the spatial distribution and areal extent of forest between GLC 2000-NCA and the other maps, however, GLC 2000-NCA provides additional information on the spatial distribution of forest types. The GLC 2000-NCA map was produced at the continental level incorporating specific needs of the region.

Effects of in ovo feeding of l-arginine on hatchability, hatching time, early posthatch development, and carcass traits in domestic pigeons (Columba livia).

Science.gov (United States)

Zhang, X Y; Wan, X P; Miao, L P; Zou, X T; Dong, X Y

2017-10-01

The objective of this research was to test the hypothesis that in ovo feeding of arginine (Arg) may improve hatchability and posthatch performance in domestic pigeons (). A completely randomized design ( = 3) with an Arg feeding treatment (Arg group, 1.14 mg Arg dissolved in 200 μL of 0.75% NaCl buffered saline as 1% concentration compared to total Arg in the egg), a buffered saline feeding treatment (SC group, 7.5 g NaCl dissolved in 1 L sterile distilled water as the concentration of poultry physiological saline), and a nonfeeding treatment (NC group) was used. Six squabs from each treatment were randomly sampled on day of hatch (DOH), posthatch d 7 (D7), and posthatch d 14 (D14), respectively. Hatchability, hatch time, BW, organ development, and carcass traits were examined. Results showed that in ovo feeding of the Arg solution increased ( < 0.05) the hatchability and advanced ( < 0.05) the hatching time in comparison with those of the other groups. Body weight of pigeon squabs that received Arg in ovo feeding was heavier ( < 0.05) on DOH and D14 than that of the NC group, and a greater ( < 0.05) BW gain from DOH to D14 and D7 to D14 was observed. Three clusters of 12 organs were classified according to the changes of organ indices. Squabs provided the Arg in ovo feeding treatment gained a priority in organ development. The heart index and gizzard index on D7 and the proventriculus index on D14 of squabs receiving Arg in ovo feeding were increased ( < 0.05) compared to those of the other groups. The brain index on DOH, the small intestine index and pancreas index on D7, and the liver index, pancreas index, and spleen index on D14 of squabs fed Arg were higher ( < 0.05) than those of the NC group. The spleen index on D7 and the small intestine index on D14 of squabs provided the Arg feeding treatment were enhanced ( < 0.05) compared with those of the SC group. The semieviscerated carcass weight of squabs receiving Arg was higher ( < 0.05) on D14 than that of

Linking sex differences in corticosterone with individual reproductive behaviour and hatch success in two species of uniparental shorebirds.

Science.gov (United States)

Edwards, Darryl B; Chin, Eunice H; Burness, Gary; Gilchrist, H Grant; Schulte-Hostedde, Albrecht I

2013-09-01

In birds, corticosterone (CORT) appears to facilitate reproductive activity because baseline and stress-induced CORT levels are elevated in breeding individuals compared with other times of the year. In particular, CORT is lower in the sex providing most of the parental care (i.e., incubation), which could be an important adaptation to tolerate stressors that result in abandoning reproduction. Therefore, one explanation for sex differences in CORT is that lower levels are favoured during the incubation/parental phase of reproduction. Using two species of uniparental shorebird - polyandrous red phalaropes (Phalaropus fulicarius) and polygynous white-rumped sandpipers (Calidris fuscicollis) - we predicted that the incubating sex would have lower baseline and stress-induced CORT, and incubating individuals with lower CORT would more effectively defend nests against a simulated intrusion, would return more quickly afterwards, and would ultimately have higher hatch success. We found that phalaropes followed the predicted pattern: incubating individuals (males) had lower baseline and stress-induced CORT than females but for baseline CORT these differences existed prior to males commencing incubation. Incubating male phalaropes with lower baseline and stress-induced CORT returned to incubate more quickly after a disturbance and there was non-significant tendency for baseline CORT to be lower in successful nests. In sandpipers, we observed no sex differences and no significant relationships between individual CORT levels and nest defence behaviours or hatch success. Our results demonstrate that in phalaropes at least, selection favours lower baseline and stress-induced CORT during the nesting period. These results can explain sex differences in stress-induced levels of CORT, however sex differences in baseline CORT were present prior to incubation. Copyright © 2013 Elsevier Inc. All rights reserved.

Branched polynomial covering maps

DEFF Research Database (Denmark)

Hansen, Vagn Lundsgaard

1999-01-01

A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...... set. Particular studies are made of branched polynomial covering maps arising from Riemann surfaces and from knots in the 3-sphere....

Mean species cover: a harmonized indicator of shrub cover for forest inventories

Science.gov (United States)

Iciar Alberdi; Sonia Condés; Ronald E. Mcroberts; Susanne Winter

2018-01-01

Because shrub cover is related to many forest ecosystem functions, it is one of the most relevant variables for describing these communities. Nevertheless, a harmonized indicator of shrub cover for large-scale reporting is lacking. The aims of the study were threefold: to define a shrub indicator that can be used by European countries for harmonized shrub cover...

Transport stress induces heart damage in newly hatched chicks via blocking the cytoprotective heat shock response and augmenting nitric oxide production.

Science.gov (United States)

Sun, F; Zuo, Y-Z; Ge, J; Xia, J; Li, X-N; Lin, J; Zhang, C; Xu, H-L; Li, J-L

2018-04-20

Transport stress affects the animal's metabolism and psychological state. As a pro-survival pathway, the heat shock response (HSR) protects healthy cells from stressors. However, it is unclear whether the HSR plays a role in transport stress-induced heart damage. To evaluate the effects of transport stress on heart damage and HSR protection, newly hatched chicks were treated with transport stress for 2 h, 4 h and 8 h. Transport stress caused decreases in body weight and increases in serum creatine kinase (CK) activity, nitric oxide (NO) content in heart tissue, cardiac nitric oxide syntheses (NOS) activity and NOS isoforms transcription. The mRNA expression of heat shock factors (HSFs, including HSF1-3) and heat shock proteins (HSPs, including HSP25, HSP40, HSP47, HSP60, HSP70, HSP90 and HSP110) in the heart of 2 h transport-treated chicks was upregulated. After 8 h of transport stress in chicks, the transcription levels of the same HSPs and HSF2 were reduced in the heart. It was also found that the changes in the HSP60, HSP70 and HSP90 protein levels had similar tendencies. These results suggested that transport stress augmented NO generation through enhancing the activity of NOS and the transcription of NOS isoforms. Therefore, this study provides new evidence that transport stress induces heart damage in the newly hatched chicks by blocking the cytoprotective HSR and augmenting NO production.

Land-cover change detection

Science.gov (United States)

Chen, Xuexia; Giri, Chandra; Vogelmann, James

2012-01-01

Land cover is the biophysical material on the surface of the earth. Land-cover types include grass, shrubs, trees, barren, water, and man-made features. Land cover changes continuously.  The rate of change can be either dramatic and abrupt, such as the changes caused by logging, hurricanes and fire, or subtle and gradual, such as regeneration of forests and damage caused by insects (Verbesselt et al., 2001).  Previous studies have shown that land cover has changed dramatically during the past sevearal centuries and that these changes have severely affected our ecosystems (Foody, 2010; Lambin et al., 2001). Lambin and Strahlers (1994b) summarized five types of cause for land-cover changes: (1) long-term natural changes in climate conditions, (2) geomorphological and ecological processes, (3) human-induced alterations of vegetation cover and landscapes, (4) interannual climate variability, and (5) human-induced greenhouse effect.  Tools and techniques are needed to detect, describe, and predict these changes to facilitate sustainable management of natural resources.

Effects of water salinity on hatching of egg, growth and survival of larvae and fingerlings of snake head fish, Channa striatus

Directory of Open Access Journals (Sweden)

Thumronk Amornsakun

2017-04-01

Full Text Available A study on the effect of water salinity ranging from 0-30 ppt on hatching success of snake head fish, Channa striatus was conducted in a 15-liter glass aquarium (water volume 10 liters containing 500 eggs for various levels of water salinity. Fertilization rates at 0, 5, 10, 11, 12, 13 and 14 ppt were 69.33, 72.67, 71.33, 72.67, 82.00, 73.33 and 10.67%, respectively. The fertilization rate at 12-13 ppt salinity was significantly (P0.05 among 0, 5 and 10 ppt.

Suplementos utilizados como hidratantes nas fases pré-alojamento e pós-alojamento para pintos recém eclodidos Supplements used as hydrating agents in pre- and post-lodging phases to newly-hatched chicks

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Adriana Ayres Pedroso

2005-07-01

Full Text Available Dois experimentos foram conduzidos, para avaliar hidratantes em pintos oriundos de matrizes, em início de vida produtiva. O primeiro experimento estudou o efeito de hidratante comercial, na fase pré-alojamento, em pintos oriundos de matrizes com 25 semanas de idade, submetidos a dois intervalos entre nascimento e alojamento (0 e 48 horas; o agente não apresentou qualquer efeito favorável sobre a desidratação, a mortalidade e o desempenho até 21 dias. No segundo experimento, foi utilizado o bicarbonato de sódio como hidratante. A solução foi fornecida, durante 24 horas, a pintos oriundos de matrizes com 27 semanas de idade, após 0, 24 e 48 horas de intervalo entre nascimento e alojamento. Foi observada melhora na integridade do intestino, representada pelo aumento na densidade intestinal e peso do órgão com a suplementação eletrolítica. O aumento no intervalo entre nascimento e alojamento diminuiu o saco vitelino. Em ambos os experimentos, o aumento no intervalo entre o nascimento e o alojamento aumentou a desidratação e a mortalidade das aves, mas propiciou melhora no desempenho aos 21 dias, não tendo sido observados efeitos positivos dos hidratantes testados.Two experiments were carried out to evaluate hydrating agents to newly hatched chicks from breeders in early production life. The first experiment studied the effect of commercial hydrating agents in pre-lodging phase in chicks from breeders with 25 weeks of age and submitted to two intervals between hatching and lodging (0 and 48 hours. Agent did not show any favorable effects on dehydration, mortality and performance until 21 days of age. In he second experiment, sodium bicarbonate was used as hydrating agent. The solution was supplied for 24 hours, after 0, 24 and 48 hours intervals between hatching and lodging, to chicks from breeder of 27 weeks of age. The intestinal integrity increased, based on intestinal density and organ weight increment obtained with

Use of ephippial morphology to assess richness of anomopods: potentials and pitfalls

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Luc DE MEESTER

2004-09-01

Full Text Available Zooplankton species richness is typically assessed through analysis of active community samples. These samples ought to be collected at many different locations in the lake and at multiple occasions throughout the year so as to cover the spatial and temporal heterogeneity in active community structure. A number of studies have shown that high numbers of species can be retrieved with a limited effort through hatching of dormant eggs isolated from lake sediments. However, dormant eggs of different species differ in their propensities to hatch, resulting in biased assessments of species composition, abundance and richness. In this paper, we explore the potentials and pitfalls of a third method to assess cladoceran species richness. For twenty European lakes, we identified the number of ephippium morphotypes in sediment samples taken on a single occasion. The morphotype richness was well correlated with species richness as assessed through hatching of dormant forms and through analysis of active community samples covering a six month period. However, not all species had a species-specific ephippial morphotype, consequently resulting in an underestimation of true species richness.

77 FR 48733 - Transitional Program for Covered Business Method Patents-Definitions of Covered Business Method...

Science.gov (United States)

2012-08-14

... Office 37 CFR Part 42 Transitional Program for Covered Business Method Patents--Definitions of Covered... Business Method Patents-- Definitions of Covered Business Method Patent and Technological Invention AGENCY... forth in detail the definitions of the terms ``covered business method patent'' and ``technological...

Mom's shadow: structure-from-motion in newly hatched chicks as revealed by an imprinting procedure.

Science.gov (United States)

Mascalzoni, Elena; Regolin, Lucia; Vallortigara, Giorgio

2009-03-01

The ability to recognize three-dimensional objects from two-dimensional (2-D) displays was investigated in domestic chicks, focusing on the role of the object's motion. In Experiment 1 newly hatched chicks, imprinted on a three-dimensional (3-D) object, were allowed to choose between the shadows of the familiar object and of an object never seen before. In Experiments 2 and 3 random-dot displays were used to produce the perception of a solid shape only when set in motion. Overall, the results showed that domestic chicks were able to recognize familiar shapes from 2-D motion stimuli. It is likely that similar general mechanisms underlying the perception of structure-from-motion and the extraction of 3-D information are shared by humans and animals. The present data shows that they occur similarly in birds as known for mammals, two separate vertebrate classes; this possibly indicates a common phylogenetic origin of these processes.

Ultradian activity rhythms in large groups of newly hatched chicks (Gallus gallus domesticus).

Science.gov (United States)

Nielsen, B L; Erhard, H W; Friggens, N C; McLeod, J E

2008-07-01

A clutch of young chicks housed with a mother hen exhibit ultradian (within day) rhythms of activity corresponding to the brooding cycle of the hen. In the present study clear evidence was found of ultradian activity rhythms in newly hatched domestic chicks housed in groups larger than natural clutch size without a mother hen or any other obvious external time-keeper. No consistent synchrony was found between groups housed in different pens within the same room. The ultradian rhythms disappeared with time and little evidence of group rhythmicity remained by the third night. This disappearance over time suggests that the presence of a mother hen may be pivotal for the long-term maintenance of these rhythms. The ultradian rhythm of the chicks may also play an important role in the initiation of brooding cycles during the behavioural transition of the mother hen from incubation to brooding. Computer simulations of individual activity rhythms were found to reproduce the observations made on a group basis. This was achievable even when individual chick rhythms were modelled as independent of each other, thus no assumptions of social facilitation are necessary to obtain ultradian activity rhythms on a group level.

Covering folded shapes

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Oswin Aichholzer

2014-05-01

Full Text Available Can folding a piece of paper flat make it larger? We explore whether a shape S must be scaled to cover a flat-folded copy of itself. We consider both single folds and arbitrary folds (continuous piecewise isometries \\(S\\to\\mathbb{R}^2\\. The underlying problem is motivated by computational origami, and is related to other covering and fixturing problems, such as Lebesgue's universal cover problem and force closure grasps. In addition to considering special shapes (squares, equilateral triangles, polygons and disks, we give upper and lower bounds on scale factors for single folds of convex objects and arbitrary folds of simply connected objects.

Land cover and water yield: inference problems when comparing catchments with mixed land cover

Directory of Open Access Journals (Sweden)

A. I. J. M. van Dijk

2012-09-01

Full Text Available Controlled experiments provide strong evidence that changing land cover (e.g. deforestation or afforestation can affect mean catchment streamflow (Q. By contrast, a similarly strong influence has not been found in studies that interpret Q from multiple catchments with mixed land cover. One possible reason is that there are methodological issues with the way in which the Budyko framework was used in the latter type studies. We examined this using Q data observed in 278 Australian catchments and by making inferences from synthetic Q data simulated by a hydrological process model (the Australian Water Resources Assessment system Landscape model. The previous contrasting findings could be reproduced. In the synthetic experiment, the land cover influence was still present but not accurately detected with the Budyko- framework. Likely sources of interpretation bias demonstrated include: (i noise in land cover, precipitation and Q data; (ii additional catchment climate characteristics more important than land cover; and (iii covariance between Q and catchment attributes. These methodological issues caution against the use of a Budyko framework to quantify a land cover influence in Q data from mixed land-cover catchments. Importantly, however, our findings do not rule out that there may also be physical processes that modify the influence of land cover in mixed land-cover catchments. Process model simulations suggested that lateral water redistribution between vegetation types and recirculation of intercepted rainfall may be important.

Relationship between weight, age and hatching success and the concentration of heavy metals in nestling blue macaw (Anodorhynchus hyacinthinus Latham, 1790 in the Pantanal,Mato Grosso do Sul

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Marina Drago Marchesi

2015-06-01

Full Text Available Abstract: The concentration of heavy metals (Cr, Fe, Al, As, Cd, Cu, Pb, Mo, Ni, Se and Zn was evaluated in the blood of nestling blue macaws (Anodorhynchus hyacinthinus captured in the Pantanal, Mato Grosso do Sul (n=26 in 2012; this was based on the hypothesis that these birds exhibit levels of these heavy metals in their organism and that these interfere in hatching success, weight and age of the chicks. Blood samples were digested with nitric acid and hydrochloric acid and the quantification of metals was performed by ICP-OES (Optical Emission Spectroscopy and Inductively Coupled Plasma. Blood samples of nestlings showed concentrations of Cr (0.10μg/g Fe (3.06μg/g Al (3.46μg/g, Cd (0.25μg/g Cu (0.74μg/g, Mo (0.33μg/g, Ni (0.61μg/g, Se (0.98μg/g, and Zn (2.08μg/g. The levels of heavy metals found were not associated with weight, age and hatching success of the chicks.

Armored Geomembrane Cover Engineering

Directory of Open Access Journals (Sweden)

Kevin Foye

2011-06-01

Full Text Available Geomembranes are an important component of modern engineered barriers to prevent the infiltration of stormwater and runoff into contaminated soil and rock as well as waste containment facilities—a function generally described as a geomembrane cover. This paper presents a case history involving a novel implementation of a geomembrane cover system. Due to this novelty, the design engineers needed to assemble from disparate sources the design criteria for the engineering of the cover. This paper discusses the design methodologies assembled by the engineering team. This information will aid engineers designing similar cover systems as well as environmental and public health professionals selecting site improvements that involve infiltration barriers.

Influence of post hatch dietary supplementation of fat on performance, carcass cuts and biochemical profile in Ven Cobb broiler

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Komal Prasad Rai

2015-02-01

Full Text Available Aim: The present experiment was conducted to study the effect of post hatch dietary fat supplementation on performance of broiler chicken. Materials and Methods: A total of 120 day-old Ven Cobb broiler chicks were randomly assigned to 4 treatment groups of 30 chicks in each (three replicates of 10 birds/treatment. The trial lasted for 35 days. The experimental design was a completely randomized design. Four types of diet were formulated for 1st week: T1, T2, T3 and T4 contained control diet with no added fat, 2.5, 5 and 7.5% fat, respectively. After 1st week post-hatch period chicks were fed ad libitum with the normal basal diet as per Bureau of Indian Standard recommendations till completion of the experiment (8-35 days. Results: Significantly higher (p<0.05 body weight and improved feed conversion ratio (FCR was recorded in birds fed 5% dietary fat at the end of the experiment whereas, feed intake was not significantly affected. Significantly (p<0.05 higher dressed weight was observed due to 5% fat supplementation than other groups whereas, it was not significant for other carcass cuts. No significant differences were observed in moisture, protein and lipid content of breast and thigh muscle of broiler due to supplemented fat whereas, 2.5% dietary fat significantly (p<0.05 increase the serum HI titer on day 28th. In biochemical profile, higher serum albumin (g/dl was recorded due to 5% fat supplementation whereas other biochemical components did not show any significance difference among treatments. Conclusion: It may be concluded that supplementation of fat in broilers diet improves the overall FCR, dressing percentage and gain more body weight.

40 CFR 63.921 - Definitions.

Science.gov (United States)

2010-07-01

... subpart that references the use of this subpart, then the definition in this subpart shall take precedence...,” cargo tank trucks, and tank railcars. Closure device means a cover, cap, hatch, lid, plug, seal, valve... opening in a container or its cover when the device is secured in the closed position. Closure devices...

MANAGEMENT EFFECTS ON GROUND COVER CLUMPINESS: SCALING FROM FIELD TO SENTINEL-2 COVER ESTIMATES

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P. Scarth

2017-11-01

Full Text Available Significant progress has been made in the development of cover data and derived products based on remotely sensed fractional cover information and field data across Australia, and these cover data sets are now used for quantifying and monitoring grazing land condition. The availability of a dense time-series of nearly 30 years of cover data to describe the spatial and temporal patterns in landscape changes over time can help with monitoring the effectiveness of grazing land management practice change. With the advent of higher spatial resolution data, such as that provided by the Copernicus Sentinel 2 series of satellites, we can look beyond reporting purely on cover amount and more closely at the operational monitoring and reporting on spatial arrangement of cover and its links with land condition. We collected high spatial resolution cover transects at 20 cm intervals over the Wambiana grazing trials in the Burdekin catchment in Queensland, Australia. Spatial variance analysis was used to determine the cover autocorrelation at various support intervals. Coincident Sentinel-2 imagery was collected and processed over all the sites providing imagery to link with the field data. We show that the spatial arrangement and temporal dynamics of cover are important indicators of grazing land condition for both productivity and water quality outcomes. The metrics and products derived from this research will assist land managers to prioritize investment and practice change strategies for long term sustainability and improved water quality, particularly in the Great Barrier Reef catchments.

Landfill covers for dry environments

International Nuclear Information System (INIS)

Dwyer, S.F.

1996-01-01

A large-scale landfill cover field test is currently underway at Sandia National Laboratories in Albuquerque, New Mexico. It is intended to compare and document the performance of alternative landfill cover technologies of various costs and complexities for interim stabilization and/or final closure of landfills in arid and semi-arid environments. Test plots of traditional designs recommended by the US Environmental Protection Agency for both RCRA Subtitle open-quote C close-quote and open-quote D close-quote regulated facilities have been constructed side-by-side with the alternative covers and will serve as baselines for comparison to these alternative covers. The alternative covers were designed specifically for dry environments. The covers will be tested under both ambient and stressed conditions. All covers have been instrumented to measure water balance variables and soil temperature. An on-site weather station records all pertinent climatological data. A key to acceptance of an alternative environmental technology is seeking regulatory acceptance and eventual permitting. The lack of acceptance by regulatory agencies is a significant barrier to development and implementation of innovative cover technologies. Much of the effort on this demonstration has been toward gaining regulatory and public acceptance

On approximating restricted cycle covers

NARCIS (Netherlands)

Manthey, Bodo

2008-01-01

A cycle cover of a graph is a set of cycles such that every vertex is part of exactly one cycle. An $L$-cycle cover is a cycle cover in which the length of every cycle is in the set $L$. The weight of a cycle cover of an edge-weighted graph is the sum of the weights of its edges. We come close to

An Administrative Meter Maid: Using Inter Partes Review and Post-Grant Review to Curb Exclusivity Parking via the "Failure to Market" Provision of the Hatch-Waxman Act.

Science.gov (United States)

Apel, Brian T

2015-01-01

Congress created the unique Hatch-Waxman framework in 1984 to increase the availability of low-cost generic drugs while preserving patent incentives for new drug development. The Hatch-Waxman Act rewards generic drug companies that successfully challenge a pharmaceutical patent: 180 days of market exclusivity before any other generic firm can enter the market. When a generic firm obtains this reward, sometimes drug developers agree to pay generic firms to delay entering the market. These pay-for-delay agreements give rise to exclusivity parking and run counter to congressional intent by delaying full generic drug competition. The Medicare Prescription Drug, Improvement, and Modernization Act created several statutory forfeiture provisions that proved only marginally effective at curbing the practice of exclusivity parking. More recently, Congress created new quasi-judicial administrative proceedings that effectively replace certain kinds of district court patent litigation. This Note describes the complex statutory scheme that gave rise to exclusivity parking, explains why previous and current attempts to curtail exclusivity parking were and remain ineffective, and suggests amending the "failure to market" provision to include these new administrative proceedings as a way to help curb exclusivity parking.

Review on the acute Daphnia magna toxicity test – Evaluation of the sensitivity and the precision of assays performed with organisms from laboratory cultures or hatched from dormant eggs

Directory of Open Access Journals (Sweden)

Persoone G.

2009-08-01

“Culture/maintenance free” aquatic microbiotests with species of different phylogenetic groups were developed in the early 1990s at the Laboratory for Environmental Toxicology and Aquatic Ecology at the Ghent University in Belgium. These assays which were given the generic name “Toxkits”, are unique in that they employ dormant stages (“cryptobiotic eggs” of the test species, which can be stored for long periods of time and “hatched” at the time of performance of the assays. One of these microbiotests is the Daphtoxkit F magna, which is currently used in many laboratories worldwide for research as well as for toxicity monitoring purposes. The microbiotest technology has several advantages in comparison to the “traditional” tests based on laboratory cultures, especially its independence of the stock culturing burden. However, the acceptance (or possible non-acceptance of performing assays with test organisms obtained from “dormant eggs” should be clearly dictated by the “sensitivity” and “precision” criteria of the former assays in comparison to the latter. The first part of this review therefore thoroughly reviews the scientific literature and of data obtained from various laboratories for assays performed with either D. magna test organisms obtained from lab cultures or hatched from dormant eggs. Attention has focused on data of quality control tests performed on reference chemicals, and in particular on potassium dichromate (K2Cr2O7 for which an acceptability range of 0.6–2.1 mg·L–1 has been set in ISO standard 6341 for the 24 h EC50 of the acute D. magna assay. Mean EC50s, standard deviations and variation coefficients were calculated from the collected data, all of which are presented in tables and figures and discussed in detail. The major conclusions drawn from the analysis of the large number of quality control (QC data on the acute D. magna toxicity test are that : (1 Virtually all results from assays performed with

Completion of the National Land Cover Database (NLCD) 1992-2001 Land Cover Change Retrofit Product

Science.gov (United States)

The Multi-Resolution Land Characteristics Consortium has supported the development of two national digital land cover products: the National Land Cover Dataset (NLCD) 1992 and National Land Cover Database (NLCD) 2001. Substantial differences in imagery, legends, and methods betwe...

Climate Impacts of Cover Crops

Science.gov (United States)

Lombardozzi, D.; Wieder, W. R.; Bonan, G. B.; Morris, C. K.; Grandy, S.

2016-12-01

Cover crops are planted in agricultural rotation with the intention of protecting soil rather than harvest. Cover crops have numerous environmental benefits that include preventing soil erosion, increasing soil fertility, and providing weed and pest control- among others. In addition to localized environmental benefits, cover crops can have important regional or global biogeochemical impacts by increasing soil organic carbon, changing emissions of greenhouse trace gases like nitrous oxide and methane, and reducing hydrologic nitrogen losses. Cover crops may additionally affect climate by changing biogeophysical processes, like albedo and latent heat flux, though these potential changes have not yet been evaluated. Here we use the coupled Community Atmosphere Model (CAM5) - Community Land Model (CLM4.5) to test how planting cover crops in the United States may change biogeophysical fluxes and climate. We present seasonal changes in albedo, heat fluxes, evaporative partitioning, radiation, and the resulting changes in temperature. Preliminary analyses show that during seasons when cover crops are planted, latent heat flux increases and albedo decreases, changing the evaporative fraction and surface temperatures. Understanding both the biogeophysical changes caused by planting cover crops in this study and the biogeochemical changes found in other studies will give a clearer picture of the overall impacts of cover crops on climate and atmospheric chemistry, informing how this land use strategy will impact climate in the future.

Factors affecting the duration of nestling period and fledging order in Tengmalm's owl (Aegolius funereus: effect of wing length and hatching sequence.

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Marek Kouba

Full Text Available In altricial birds, the nestling period is an important part of the breeding phase because the juveniles may spend quite a long time in the nest, with associated high energy costs for the parents. The length of the nestling period can be variable and its duration may be influenced by both biotic and abiotic factors; however, studies of this have mostly been undertaken on passerine birds. We studied individual duration of nestling period of 98 Tengmalm's owl chicks (Aegolius funereus at 27 nests during five breeding seasons using a camera and chip system and radio-telemetry. We found the nestlings stayed in the nest box for 27 - 38 days from hatching (mean ± SD, 32.4 ± 2.2 days. The individual duration of nestling period was negatively related to wing length, but no formally significant effect was found for body weight, sex, prey availability and/or weather conditions. The fledging sequence of individual nestlings was primarily related to hatching order; no relationship with wing length and/or other factors was found in this case. We suggest the length of wing is the most important measure of body condition and individual quality in Tengmalm's owl young determining the duration of the nestling period. Other differences from passerines (e.g., the lack of effect of weather or prey availability on nestling period are considered likely to be due to different life-history traits, in particular different food habits and nesting sites and greater risk of nest predation among passerines.

Completion of the National Land Cover Database (NLCD) 1992–2001 Land Cover Change Retrofit product

Science.gov (United States)

Fry, J.A.; Coan, Michael; Homer, Collin G.; Meyer, Debra K.; Wickham, J.D.

2009-01-01

The Multi-Resolution Land Characteristics Consortium has supported the development of two national digital land cover products: the National Land Cover Dataset (NLCD) 1992 and National Land Cover Database (NLCD) 2001. Substantial differences in imagery, legends, and methods between these two land cover products must be overcome in order to support direct comparison. The NLCD 1992-2001 Land Cover Change Retrofit product was developed to provide more accurate and useful land cover change data than would be possible by direct comparison of NLCD 1992 and NLCD 2001. For the change analysis method to be both national in scale and timely, implementation required production across many Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) path/rows simultaneously. To meet these requirements, a hybrid change analysis process was developed to incorporate both post-classification comparison and specialized ratio differencing change analysis techniques. At a resolution of 30 meters, the completed NLCD 1992-2001 Land Cover Change Retrofit product contains unchanged pixels from the NLCD 2001 land cover dataset that have been cross-walked to a modified Anderson Level I class code, and changed pixels labeled with a 'from-to' class code. Analysis of the results for the conterminous United States indicated that about 3 percent of the land cover dataset changed between 1992 and 2001.

Automatic design of magazine covers

Science.gov (United States)

Jahanian, Ali; Liu, Jerry; Tretter, Daniel R.; Lin, Qian; Damera-Venkata, Niranjan; O'Brien-Strain, Eamonn; Lee, Seungyon; Fan, Jian; Allebach, Jan P.

2012-03-01

In this paper, we propose a system for automatic design of magazine covers that quantifies a number of concepts from art and aesthetics. Our solution to automatic design of this type of media has been shaped by input from professional designers, magazine art directors and editorial boards, and journalists. Consequently, a number of principles in design and rules in designing magazine covers are delineated. Several techniques are derived and employed in order to quantify and implement these principles and rules in the format of a software framework. At this stage, our framework divides the task of design into three main modules: layout of magazine cover elements, choice of color for masthead and cover lines, and typography of cover lines. Feedback from professional designers on our designs suggests that our results are congruent with their intuition.

Do cover crop mixtures have the same ability to suppress weeds as competitive monoculture cover crops?

Directory of Open Access Journals (Sweden)

Brust, Jochen

2014-02-01

Full Text Available An increasing number of farmers use cover crop mixtures instead of monoculture cover crops to improve soil and crop quality. However, only little information is available about the weed suppression ability of cover crop mixtures. Therefore, two field experiments were conducted in Baden-Württemberg between 2010 and 2012, to compare growth and weed suppression of monoculture cover crops and cover crop mixtures. In the first experiment, heterogeneous results between yellow mustard and the cover crop mixture occurred. For further research, a field experiment was conducted in 2012 to compare monocultures of yellow mustard and hemp with three cover crop mixtures. The evaluated mixtures were: “MELO”: for soil melioration; “BETA”: includes only plant species with no close relation to main cash crops in Central Europe and “GPS”: for usage as energy substrate in spring. Yellow mustard, MELO, BETA and GPS covered 90% of the soil in less than 42 days and were able to reduce photosynthetically active radiation (PAR on soil surface by more than 96% after 52 days. Hemp covered 90% of the soil after 47 days and reduced PAR by 91% after 52 days. Eight weeks after planting, only BETA showed similar growth to yellow mustard which produced the highest dry matter. The GPS mixture had comparatively poor growth, while MELO produced similar dry matter to hemp. Yellow mustard, MELO and BETA reduced weed growth by 96% compared with a no cover crop control, while hemp and GPS reduced weeds by 85% and 79%. In spring, weed dry matter was reduced by more than 94% in plots with yellow mustard and all mixtures, while in hemp plots weeds were only reduced by 71%. The results suggest that the tested cover crop mixtures offer similar weed suppression ability until spring as the monoculture of the competitive yellow mustard.

Gainesville's urban forest canopy cover

Science.gov (United States)

Francisco Escobedo; Jennifer A. Seitz; Wayne Zipperer

2009-01-01

Ecosystem benefits from trees are linked directly to the amount of healthy urban forest canopy cover. Urban forest cover is dynamic and changes over time due to factors such as urban development, windstorms, tree removals, and growth. The amount of a city's canopy cover depends on its land use, climate, and people's preferences. This fact sheet examines how...

Mapping land cover through time with the Rapid Land Cover Mapper—Documentation and user manual

Science.gov (United States)

Cotillon, Suzanne E.; Mathis, Melissa L.

2017-02-15

The Rapid Land Cover Mapper is an Esri ArcGIS® Desktop add-in, which was created as an alternative to automated or semiautomated mapping methods. Based on a manual photo interpretation technique, the tool facilitates mapping over large areas and through time, and produces time-series raster maps and associated statistics that characterize the changing landscapes. The Rapid Land Cover Mapper add-in can be used with any imagery source to map various themes (for instance, land cover, soils, or forest) at any chosen mapping resolution. The user manual contains all essential information for the user to make full use of the Rapid Land Cover Mapper add-in. This manual includes a description of the add-in functions and capabilities, and step-by-step procedures for using the add-in. The Rapid Land Cover Mapper add-in was successfully used by the U.S. Geological Survey West Africa Land Use Dynamics team to accurately map land use and land cover in 17 West African countries through time (1975, 2000, and 2013).

Climate under cover

CERN Document Server

Takakura, Tadashi

2002-01-01

1.1. INTRODUCTION Plastic covering, either framed or floating, is now used worldwide to protect crops from unfavorable growing conditions, such as severe weather and insects and birds. Protected cultivation in the broad sense, including mulching, has been widely spread by the innovation of plastic films. Paper, straw, and glass were the main materials used before the era of plastics. Utilization of plastics in agriculture started in the developed countries and is now spreading to the developing countries. Early utilization of plastic was in cold regions, and plastic was mainly used for protection from the cold. Now plastic is used also for protection from wind, insects and diseases. The use of covering techniques started with a simple system such as mulching, then row covers and small tunnels were developed, and finally plastic houses. Floating mulch was an exception to this sequence: it was introduced rather recently, although it is a simple structure. New development of functional and inexpensive films trig...

Alternative cover design

International Nuclear Information System (INIS)

1988-11-01

The special study on Alternative Cover Designs is one of several studies initiated by the US Department of Energy (DOE) in response to the proposed US Environmental Protection Agency (EPA) groundwater standards. The objective of this study is to investigate the possibility of minimizing the infiltration of precipitation through stabilized tailings piles by altering the standard design of covers currently used on the Uranium Mill Tailings Remedial Action (UMTRA) Project. Prior. to the issuance of the proposed standards, UMTRA Project piles had common design elements to meet the required criteria, the most important of which were for radon diffusion, long-term stability, erosion protection, and groundwater protection. The standard pile covers consisted of three distinct layers. From top to bottom they were: rock for erosion protection; a sand bedding layer; and the radon barrier, usually consisting of a clayey sand material, which also functioned to limit infiltration into the tailings. The piles generally had topslopes from 2 to 4 percent and sideslopes of 20 percent

Benthic Cover

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Benthic cover (habitat) maps are derived from aerial imagery, underwater photos, acoustic surveys, and data gathered from sediment samples. Shallow to moderate-depth...

Special study on vegetative covers

International Nuclear Information System (INIS)

1988-11-01

This report describes the findings of a special study on the use of vegetative covers to stabilize tailings piles for the Uranium Mill Tailings Remedial Action (UMTRA) Project. The principal rationale for using plants would be to establish a dynamic system for controlling water balance. Specifically, vegetation would be used to intercept and transpire precipitation to the atmosphere, rather than allowing water to drain into the tailings and mobilize contaminants. This would facilitate compliance with groundwater standards proposed for the UMTRA Project by the Environmental Protection Agency. The goals of the study were to evaluate the feasibility of using vegetative covers on UMTRA Project piles, define the advantages and disadvantages of vegetative covers, and develop general guidelines for their use when such use seems reasonable. The principal method for the study was to analyze and apply to the UMTRA Project the results of research programs on vegetative covers at other US Department of Energy (DOE) waste management facilities. The study also relied upon observations made of existing stabilized piles at UMTRA Project sites where natural vegetation is growing on the rock-covered surfaces. Water balance and erosion models were also used to quantify the long-term performance of vegetative covers planned for the topslopes of stabilized piles at Grand Junction and Durango, Colorado, two UMTRA Project sites where the decision was made during the course of this special study to use vegetative covers. Elements in the design and construction of the vegetative covers at these two sites are discussed in the report, with explanations of the differing features that reflect differing environmental conditions. 28 refs., 18 figs., 9 tabs

Evaluation of burial ground soil covers

International Nuclear Information System (INIS)

Fenimore, J.W.

1976-11-01

Solid radioactive waste burial at the Savannah River Plant between 1955 and 1972 filled a 76-acre site. Burial operations then were shifted to an adjacent site, and a program was begun to develop a land cover that would: (1) minimize soil erosion; and (2) protect the buried waste from deep-rooted plants, since radionuclides can be recycled by uptake through root systems. In anticipation of the need for a suitable soil cover, five grass species were planted on 20 plots (4 plots of each species) at the burial ground (Facility 643-G) in 1969. The grass plots were planted for evaluation of viability, root depth, and erosion protection existing under conditions of low fertility and minimum care. In addition, 16 different artificial soil covers were installed on 32 plots (each cover on two plots) to evaluate: (1) resistance of cover to deterioration from weathering; (2) resistance of cover to encroachment by deep-rooted plants; and (3) soil erosion protection provided by the cover. All test plots were observed and photographed in 1970 and in 1974. After both grass and artificial soil covers were tested five years, the following results were observed: Pensacola Bahia grass was the best of the five cover grasses tested; and fifteen of the sixteen artificial covers that were tested controlled vegetation growth and soil erosion. Photographs of the test plots will be retaken at five-year intervals for future documentation

Optimal shortening of uniform covering arrays.

Directory of Open Access Journals (Sweden)

Jose Torres-Jimenez

Full Text Available Software test suites based on the concept of interaction testing are very useful for testing software components in an economical way. Test suites of this kind may be created using mathematical objects called covering arrays. A covering array, denoted by CA(N; t, k, v, is an N × k array over [Formula: see text] with the property that every N × t sub-array covers all t-tuples of [Formula: see text] at least once. Covering arrays can be used to test systems in which failures occur as a result of interactions among components or subsystems. They are often used in areas such as hardware Trojan detection, software testing, and network design. Because system testing is expensive, it is critical to reduce the amount of testing required. This paper addresses the Optimal Shortening of Covering ARrays (OSCAR problem, an optimization problem whose objective is to construct, from an existing covering array matrix of uniform level, an array with dimensions of (N - δ × (k - Δ such that the number of missing t-tuples is minimized. Two applications of the OSCAR problem are (a to produce smaller covering arrays from larger ones and (b to obtain quasi-covering arrays (covering arrays in which the number of missing t-tuples is small to be used as input to a meta-heuristic algorithm that produces covering arrays. In addition, it is proven that the OSCAR problem is NP-complete, and twelve different algorithms are proposed to solve it. An experiment was performed on 62 problem instances, and the results demonstrate the effectiveness of solving the OSCAR problem to facilitate the construction of new covering arrays.

Influence of cover defects on the attenuation of radon with earthen covers

International Nuclear Information System (INIS)

Kalkwarf, D.R.; Mayer, D.W.

1983-11-01

Experimental and theoretical evaluations of radon flux through laboratory-scale defective soil columns are presented together with a survey of literature on the formation and prevention of defects in soil covers. This report focuses on air-filled, centimeter-scale defects that are most probable in earthen covers for attenuating radon emission from uranium-mill tailings. Examples include shirnkage and erosion cracks, erosion piping, animal burrows and air channels formed by the biodegradation of vegetation roots. Calculations based on mathematical models indicate that collections of defects which could increase the radon flux from an earthen cover by a factor of two would be easily detected by visual inspection. However, these models ignore air-turbulence in the defect and drying of the soil around the defect. Laboratory measurements showed that turbulent diffusion of radon occurred through defects as narrow as 0.3 cm when subjected to a transverse air velocity of 1 to 6 miles per hour at the surface. Both turbulence and more-rapid drying of soil can accelerate radon flux to the cover surface. Consequently, recommended methods to inhibit defect formation should be applied. 29 references, 3 figures, 5 tables

[Snow cover pollution monitoring in Ufa].

Science.gov (United States)

Daukaev, R A; Suleĭmanov, R A

2008-01-01

The paper presents the results of examining the snow cover polluted with heavy metals in the large industrial town of Ufa. The level of man-caused burden on the snow cover of the conventional parts of the town was estimated and compared upon exposure to a wide range of snow cover pollutants. The priority snow cover pollutants were identified among the test heavy metals.

Combinatorial aspects of covering arrays

Directory of Open Access Journals (Sweden)

Charles J. Colbourn

2004-11-01

Full Text Available Covering arrays generalize orthogonal arrays by requiring that t -tuples be covered, but not requiring that the appearance of t -tuples be balanced.Their uses in screening experiments has found application in software testing, hardware testing, and a variety of fields in which interactions among factors are to be identified. Here a combinatorial view of covering arrays is adopted, encompassing basic bounds, direct constructions, recursive constructions, algorithmic methods, and applications.

Forest Cover Estimation in Ireland Using Radar Remote Sensing: A Comparative Analysis of Forest Cover Assessment Methodologies

Science.gov (United States)

Devaney, John; Barrett, Brian; Barrett, Frank; Redmond, John; O`Halloran, John

2015-01-01

Quantification of spatial and temporal changes in forest cover is an essential component of forest monitoring programs. Due to its cloud free capability, Synthetic Aperture Radar (SAR) is an ideal source of information on forest dynamics in countries with near-constant cloud-cover. However, few studies have investigated the use of SAR for forest cover estimation in landscapes with highly sparse and fragmented forest cover. In this study, the potential use of L-band SAR for forest cover estimation in two regions (Longford and Sligo) in Ireland is investigated and compared to forest cover estimates derived from three national (Forestry2010, Prime2, National Forest Inventory), one pan-European (Forest Map 2006) and one global forest cover (Global Forest Change) product. Two machine-learning approaches (Random Forests and Extremely Randomised Trees) are evaluated. Both Random Forests and Extremely Randomised Trees classification accuracies were high (98.1–98.5%), with differences between the two classifiers being minimal (forest area and an increase in overall accuracy of SAR-derived forest cover maps. All forest cover products were evaluated using an independent validation dataset. For the Longford region, the highest overall accuracy was recorded with the Forestry2010 dataset (97.42%) whereas in Sligo, highest overall accuracy was obtained for the Prime2 dataset (97.43%), although accuracies of SAR-derived forest maps were comparable. Our findings indicate that spaceborne radar could aid inventories in regions with low levels of forest cover in fragmented landscapes. The reduced accuracies observed for the global and pan-continental forest cover maps in comparison to national and SAR-derived forest maps indicate that caution should be exercised when applying these datasets for national reporting. PMID:26262681

Anthelmintic activity of acetone extracts from South African plants used on egg hatching of Haemonchus contortus

Directory of Open Access Journals (Sweden)

Gerda Fouche

2016-07-01

Full Text Available The nematode, Haemonchus contortus, is responsible for major economic losses in the livestock industry. The management of parasites such as H. contortus has been through the use of synthetic parasiticides. This has resulted in the presence of residues in meat and milk, which affects food safety. The development of resistance to available anthelmintics coupled with their high cost has further complicated matters. This has led to the investigation of alternative methods to manage nematodes, including the use of plants and plant extracts as a potential source of novel anthelmintics. Acetone extracts were prepared from 15 South African plant species and their anthelmintic activity determined using the egg hatch assay (EHA. The leaf extract of Cleome gynandra had the best inhibitory activity (68% ± 3% at a concentration of 2.5 mg/mL, followed by the stem extract of Maerua angolensis (65% ± 5%. The extracts had a relatively low toxicity on Vero cells determined by the MTT (3-(4,5-dimethylthiazol-2-yl-2,5- diphenyltetrazolium bromide cellular assay.

Molecular identification of fungal isolates and hatching success of green turtle (Chelonia mydas) nests.

Science.gov (United States)

Candan, Esra Deniz

2018-02-26

The aim of this study is to investigate the fungal diversity of green turtle nests and to examine phylogenetic relationships among these isolates. During the nesting season, samples of intra-nest sand and failed eggs were collected from 25% of the surviving nests in Sugözü Beaches, which are amongst the most important nesting beaches for endangered green turtles in the Mediterranean. Twenty-three fungi were identified by molecular techniques. Fungal isolates belonged to genera Aspergillus, Emericella, Rhizopus, Actinomucor and Apophysomyces with two undescribed species. Aspergillus variecolor, Aspergillus quadrilinieatus, Aspergillus tubingensis, Rhizopus oryzae, Actinomucor elegans and Apophysomyces variabilis were firstly detected in all sea turtle nests within this study. Our results demonstrate that 36.4% of the nests had fungal contamination. Also hatching success of the nests contaminated by fungi were significantly lower than the uncontaminated nests (P = 0.029). Also, this may represent a threat to marine turtles and a risk for the health of conservation workers. This study is the first molecular phylogenetic study associated with sea turtle nests in the eastern Mediterranean coast and contributes to the wider body of literature on fungal invasion of sea turtle nests with firstly isolated species. These findings are important for improving potential conservation measures for the nest sites.

Assisted Hatching and Intracytoplasmic Sperm Injection are not Associated with Improved Outcomes in ART Cycles for Diminished Ovarian Reserve: An Analysis of US Cycles from 2004–2011

Science.gov (United States)

Butts, Samantha F.; Owen, Carter; Mainigi, Monica; Senapati, Suneeta; Seifer, David B.; Dokras, Anuja

2014-01-01

Objective To investigate the impact of intracytoplasmic sperm injection (ICSI) and assisted hatching (AH) on ART outcomes in cycles with diminished ovarian reserve (DOR) as the primary diagnosis. Design Retrospective cohort study of cycles from the SART-CORS database. Setting NA. Patient(s) A total of 422,949 fresh, non-donor, initial ART cycles of which 8,597 were diagnosed with only elevated FSH and 38,926 were diagnosed with only DOR according to the SART DOR categorization. Intervention(s) None. Main Outcome Measure(s) Live birth and clinical pregnancy rates. Result(s) ICSI and AH were associated with diminished odds of live birth in SART DOR only cycles (AOR, 95% CI 0.88, 0.81–0.96 for ICSI; AOR, 95% CI 0.77 0.71–0.84 for AH). No association between either ICSI or AH in Elevated FSH only cycles was observed. The combination of ICSI and AH resulted in significantly lower odds of live birth in SART DOR only cycles but not in Elevated FSH only cycles. Conclusion(s) In initial ART cycles for which the only indication relates to a diagnosis of diminished ovarian reserve, assisted hatching and ICSI are not associated with improved live birth rates. PMID:25086790

Covered Bridge Security Manual

Science.gov (United States)

Brett Phares; Terry Wipf; Ryan Sievers; Travis Hosteng

2013-01-01

The design, construction, and use of covered timber bridges is all but a lost art in these days of pre-stressed concrete, high-performance steel, and the significant growth both in the volume and size of vehicles. Furthermore, many of the existing covered timber bridges are preserved only because of their status on the National Registry of Historic Places or the...

Summary of decontamination cover manufacturing experience

International Nuclear Information System (INIS)

Ulrich, G.B.; Berry, H.W.

1995-02-01

Decontamination cover forming cracks and vent cup assembly leaks through the decontamination covers were early manufacturing problems. The decontamination cover total manufacturing process yield was as low as 55%. Applicable tooling and procedures were examined. All manufacturing steps from foil fabrication to final assembly leak testing were considered as possible causes or contributing factors to these problems. The following principal changes were made to correct these problems: (1) the foil annealing temperature was reduced from 1375 degrees to 1250 degrees C, (2) the decontamination cover fabrication procedure (including visual inspection for surface imperfections and elimination of superfluous operations) was improved, (3) the postforming dye penetrant inspection procedure was revised for increased sensitivity, (4) a postforming (prewelding) 1250 degrees C/1 h vacuum stress-relief operation was added, (5) a poststress relief (prewelding) decontamination cover piece-part leak test was implemented, (6) the hold-down fixture used during the decontamination cover-to-cup weld was modified, and concomitantly, and (7) the foil fabrication process was changed from the extruding and rolling of 63-mm-diam vacuum arc-remelted ingots (extrusion process) to the rolling of 19-mm-square arc-melted drop castings (drop cast process). Since these changes were incorporated, the decontamination cover total manufacturing process yield has been 91 %. Most importantly, more than 99% of the decontamination covers welded onto vent cup assemblies were acceptable. The drastic yield improvement is attributed primarily to the change in the foil annealing temperature from 1375 degrees to 1250 degrees C and secondarily to the improvements in the decontamination cover fabrication procedure

Sensitivity of selected landscape pattern metrics to land-cover misclassification and differences in land-cover composition

Science.gov (United States)

James D. Wickham; Robert V. O' Neill; Kurt H. Riitters; Timothy G. Wade; K. Bruce Jones

1997-01-01

Calculation of landscape metrics from land-cover data is becoming increasingly common. Some studies have shown that these measurements are sensitive to differences in land-cover composition, but none are known to have tested also their a sensitivity to land-cover misclassification. An error simulation model was written to test the sensitivity of selected land-scape...

Egg hatching response to a range of ultraviolet-B (UV-B) radiation doses for four predatory mites and the herbivorous spider mite Tetranychus urticae.

Science.gov (United States)

Koveos, Dimitrios S; Suzuki, Takeshi; Terzidou, Anastasia; Kokkari, Anastasia; Floros, George; Damos, Petros; Kouloussis, Nikos A

2017-01-01

Egg hatchability of four predatory mites-Phytoseiulus persimilis Athias-Henriot, Iphiseius [Amblyseius] degenerans Berlese, Amblyseius swirskii Athias-Henriot, and Euseius finlandicus Oudemans (Acari: Phytoseiidae)-and the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) was determined under various UV-B doses either in constant darkness (DD) or with simultaneous irradiation using white light. Under UV-B irradiation and DD or simultaneous irradiation with white light, the predator's eggs hatched in significantly lower percentages than in the control non-exposed eggs, which indicates deleterious effects of UV-B on embryonic development. In addition, higher hatchability percentages were observed under UV-B irradiation and DD in eggs of the predatory mites than in eggs of T. urticae. This might be caused by a higher involvement of an antioxidant system, shield effects by pigments or a mere shorter duration of embryonic development in predatory mites than in T. urticae, thus avoiding accumulative effects of UV-B. Although no eggs of T. urticae hatched under UV-B irradiation and DD, variable hatchability percentages were observed under simultaneous irradiation with white light, which suggests the involvement of a photoreactivation system that reduces UV-B damages. Under the same doses with simultaneous irradiation with white light, eggs of T. urticae displayed higher photoreactivation and were more tolerant to UV-B than eggs of the predatory mites. Among predators variation regarding the tolerance to UV-B effects was observed, with eggs of P. persimilis and I. degenerans being more tolerant to UV-B radiation than eggs of A. swirskii and E. finlandicus.

Allegheny County Land Cover Areas

Data.gov (United States)

Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Land Cover dataset demarcates 14 land cover types by area; such as Residential, Commercial, Industrial, Forest, Agriculture, etc. If viewing this description on...

Geometric covers, graph orientations, counter games

DEFF Research Database (Denmark)

Berglin, Edvin

-directed graph is dynamic (can be altered by some outside actor), some orientations may need to be reversed in order to maintain the low out-degree. We present a new algorithm that is simpler than earlier work, yet matches or outperforms the efficiency of these results with very few exceptions. Counter games...... example is Line Cover, also known as Point-Line Cover, where a set of points in a geometric space are to be covered by placing a restricted number of lines. We present new FPT algorithms for the sub-family Curve Cover (which includes Line Cover), as well as for Hyperplane Cover restricted to R 3 (i...... are a type of abstract game played over a set of counters holding values, and these values may be moved between counters according to some set of rules. Typically they are played between two players: the adversary who tries to concentrate the greatest value possible in a single counter, and the benevolent...

A globally complete map of supraglacial debris cover and a new toolkit for debris cover research

Science.gov (United States)

Herreid, Sam; Pellicciotti, Francesca

2017-04-01

A growing canon of literature is focused on resolving the processes and implications of debris cover on glaciers. However, this work is often confined to a handful of glaciers that were likely selected based on criteria optimizing their suitability to test a specific hypothesis or logistical ease. The role of debris cover in a glacier system is likely to not go overlooked in forthcoming research, yet the magnitude of this role at a global scale has not yet been fully described. Here, we present a map of debris cover for all glacierized regions on Earth including the Greenland Ice Sheet using 30 m Landsat data. This dataset will begin to open a wider context to the high quality, localized findings from the debris-covered glacier research community and help inform large-scale modeling efforts. A global map of debris cover also facilitates analysis attempting to isolate first order geomorphological and climate controls of supraglacial debris production. Furthering the objective of expanding the inclusion of debris cover in forthcoming research, we also present an under development suite of open-source, Python based tools. Requiring minimal and often freely available input data, we have automated the mapping of: i) debris cover, ii) ice cliffs, iii) debris cover evolution over the Landsat era and iv) glacier flow instabilities from altered debris structures. At the present time, debris extent is the only globally complete quantity but with the expanding repository of high quality global datasets and further tool development minimizing manual tasks and computational cost, we foresee all of these tools being applied globally in the near future.

On numerically pluricanonical cyclic coverings

International Nuclear Information System (INIS)

Kulikov, V S; Kharlamov, V M

2014-01-01

We investigate some properties of cyclic coverings f:Y→X (where X is a complex surface of general type) branched along smooth curves B⊂X that are numerically equivalent to a multiple of the canonical class of X. Our main results concern coverings of surfaces of general type with p g =0 and Miyaoka-Yau surfaces. In particular, such coverings provide new examples of multi-component moduli spaces of surfaces with given Chern numbers and new examples of surfaces that are not deformation equivalent to their complex conjugates

Habitat selection and spawning success of walleye in a tributary to Owasco Lake, New York

Science.gov (United States)

Chalupnicki, Marc A.; Johnson, James H.; McKenna, James E.; Dittman, Dawn E.

2010-01-01

Walleyes Sander vitreus are stocked into Owasco Lake, New York, to provide a sport fishery, but the population must be sustained by annual hatchery supplementation despite the presence of appropriate habitat. Therefore, we evaluated walleye spawning success in Dutch Hollow Brook, a tributary of Owasco Lake, to determine whether early survival limited recruitment. Spawning success during spring 2006 and 2007 was evaluated by estimating egg densities from samples collected in the lower 725 m of the stream. Environmental variables were also recorded to characterize the selected spawning habitat. Drift nets were set downstream of the spawning section to assess egg survival and larval drift. We estimated that 162,596 larvae hatched in 2006. For 2007, we estimated that 360,026 eggs were deposited, with a hatch of 127,500 larvae and hatching success of 35.4%. Egg density was significantly correlated to percent cover, substrate type, and depth : velocity ratio. Two sections had significantly higher egg deposition than other areas. Adult spawning walleyes selected shallow, slow habitats with some cover and gravel substrate in the accessible reaches of Dutch Hollow Brook. Our results show that walleyes found suitable spawning habitat in Dutch Hollow Brook and that egg and larval development does not appear to limit natural reproduction.

Choline requirements of White Pekin ducks from hatch to 21 days of age.

Science.gov (United States)

Wen, Z G; Tang, J; Hou, S S; Guo, Y M; Huang, W; Xie, M

2014-12-01

A dose-response experiment with 8 dietary choline levels (302, 496, 778, 990, 1,182, 1,414, 1,625, and 1,832 mg/kg) was conducted with male White Pekin ducks to estimate the choline requirement from hatch to 21 d of age. Three hundred eighty-four 1-d-old male White Pekin ducks were randomly assigned to 8 dietary treatments, each containing 6 replicate pens with 8 birds per pen. At 21 d of age, weight gain, feed intake, and feed/gain from each pen were calculated for feeding period, and 2 ducks selected randomly from each pen were euthanized and the liver was collected to determine total lipids, triglycerides, and phospholipids. In our study, perosis, poor growth, and high liver fat were all observed in choline-deficient ducks and incidence of perosis was zero when dietary choline was 1,182 mg/kg. As dietary choline increased, the weight gain and feed intake increased linearly or quadratically (P < 0.05). On the other hand, as dietary choline increased, the total lipid and triglyceride in liver decreased linearly and liver phospholipid increased linearly (P < 0.05), and the lipotropic activity of choline may be associated with increasing phospholipid at a high dietary choline level. According to broken-line regression, the choline requirements for weight gain and feed intake were 810 and 823 mg/kg, respectively, but higher requirement should be considered to prevent perosis and excess liver lipid deposition completely. ©2014 Poultry Science Association Inc.

Measuring and analyzing urban tree cover

Science.gov (United States)

David J. Nowak; Rowan A. Rowntree; E. Gregory McPherson; Susan M. Sisinni; Esther R. Kirkmann; Jack C. Stevens

1996-01-01

Measurement of city tree cover can aid in urban vegetation planning, management, and research by revealing characteristics of vegetation across a city. Urban tree cover in the United States ranges from 0.4% in Lancaster, California, to 55% in Baton Rouge, Louisiana. Two important factors that affect the amount of urban tree cover are the natural environment and land...

Quantization of noncompact coverings and its physical applications

Science.gov (United States)

Ivankov, Petr

2018-02-01

A rigorous algebraic definition of noncommutative coverings is developed. In the case of commutative algebras this definition is equivalent to the classical definition of topological coverings of locally compact spaces. The theory has following nontrivial applications: • Coverings of continuous trace algebras, • Coverings of noncommutative tori, • Coverings of the quantum SU(2) group, • Coverings of foliations, • Coverings of isospectral deformations of Spin - manifolds. The theory supplies the rigorous definition of noncommutative Wilson lines.

Percent Forest Cover

Data.gov (United States)

U.S. Environmental Protection Agency — Forests provide economic and ecological value. High percentages of forest cover (FORPCT) generally indicate healthier ecosystems and cleaner surface water. More...

MicroXRF tomographic visualization of zinc and iron in the zebrafish embryo at the onset of the hatching period

Energy Technology Data Exchange (ETDEWEB)

Bourassa, Daisy; Gleber, Sophie-Charlotte; Vogt, Stefan; Shin, Chong Hyun; Fahrni, Christoph J.

2016-01-01

Transition metals such as zinc, copper, and iron play key roles in cellular proliferation, cell differentiation, growth, and development. Over the past decade, advances in synchrotron X-ray fluorescence instrumentation presented new opportunities for the three-dimensional mapping of trace metal distributions within intact specimens. Taking advantage of microXRF tomography, we visualized the 3D distribution of zinc and iron in a zebrafish embryo at the onset of the hatching period. The reconstructed volumetric data revealed distinct differences in the elemental distributions, with zinc predominantly localized to the yolk and yolk extension, and iron to various regions of the brain as well as the myotome extending along the dorsal side of the embryo. The data set complements an earlier tomographic study of an embryo at the pharyngula stage (24 hpf), thus offering new insights into the trace metal distribution at key stages of embryonic development.

Land cover fire proneness in Europe

Directory of Open Access Journals (Sweden)

Mario Gonzalez Pereira

2014-12-01

Full Text Available Aim of study: This study aims to identify and characterize the spatial and temporal evolution of the types of vegetation that are most affected by forest fires in Europe. The characterization of the fuels is an important issue of the fire regime in each specific ecosystem while, on the other hand, fire is an important disturbance for global vegetation dynamics.Area of study: Southern European countries: Portugal, Spain, France, Italy and Greece.Material and Methods: Corine Land Cover maps for 2000 and 2006 (CLC2000, CLC2006 and burned area (BA perimeters, from 2000 to 2013 in Europe are combined to access the spatial and temporal evolution of the types of vegetation that are most affected by wild fires using descriptive statistics and Geographical Information System (GIS techniques.Main results: The spatial and temporal distribution of BA perimeters, vegetation and burnt vegetation by wild fires was performed and different statistics were obtained for Mediterranean and entire Europe, confirming the usefulness of the proposed land cover system. A fire proneness index is proposed to assess the fire selectivity of land cover classes. The index allowed to quantify and to compare the propensity of vegetation classes and countries to fire.Research highlights: The usefulness and efficiency of the land cover classification scheme and fire proneness index. The differences between northern Europe and southern Europe and among the Mediterranean region in what concerns to vegetation cover, fire incidence, area burnt in land cover classes and fire proneness between classes for the different countries.Keywords: Fire proneness; Mixed forests; Land cover/land use; Fire regime; Europe; GIS; Corine land cover. 

Scenarios of land cover in China

Science.gov (United States)

Yue, Tian Xiang; Fan, Ze Meng; Liu, Ji Yuan

2007-02-01

A method for surface modeling of land cover change (SMLC) is developed on the basis of establishing transition probability matrixes between land cover types and HLZ types. SMLC is used to simulate land cover scenarios of China for the years 2039, 2069 and 2099, for which HLZ scenarios are first simulated in terms of HadCM3 climatic scenarios that are downscaled in zonal model of spatial climate change in China. This paper also analyzes spatial distribution of land cover types, area change and mean center shift of each land cover type, ecotope diversity, and patch connectivity under the land cover scenarios. The results show that cultivated land would decrease and woodland would expand greatly with climatic change, which coincides with consequences expected by implementation of Grain-for-Green policy. Nival area would shrink, and desertification area would expand at a comparatively slow rate in future 100 years. Climate change would generally cause less ecotope diversity and more patch connectivity. Ecosystems in China would have a pattern of beneficial cycle after efficient ecological conservation and restoration. However, if human activities would exceed regulation capacity of ecosystems themselves, the ecosystems in China might deteriorate more seriously.

CLC2000 land cover database of the Netherlands; monitoring land cover changes between 1986 and 2000

OpenAIRE

Hazeu, G.W.

2003-01-01

The 1986 CORINE land cover database of the Netherlands was revised and updated on basis of Landsat satellite images and ancillary data. Interpretation of satellite images from 1986 and 2000 resulted in the CLC2000, CLC1986rev and CLCchange databases. A standard European legend and production methodology was applied. Thirty land cover classes were discerned. Most extended land cover types were pastures (231), arable land (211) and complex cultivation patterns (242). Between 1986 and 2000 aroun...

Carbon Assessment of Hawaii Land Cover Map (CAH_LandCover)

Data.gov (United States)

Department of the Interior — While there have been many maps produced that depict vegetation for the state of Hawai‘i only a few of these display land cover for all of the main Hawaiian Islands,...

Air sampling system for airborne surveys

International Nuclear Information System (INIS)

Jupiter, C.; Tipton, W.J.

1975-01-01

An air sampling system has been designed for installation on the Beechcraft King Air A-100 aircraft as a part of the Aerial Radiological Measuring System (ARMS). It is intended for both particle and whole gas sampling. The sampling probe is designed for isokinetic sampling and is mounted on a removable modified escape hatch cover, behind the co-pilot's seat, and extends about two feet forward of the hatch cover in the air stream lines. Directly behind the sampling probe inside the modified hatch cover is an expansion chamber, space for a 5-inch diameter filter paper cassette, and an optional four-stage cascade impactor for particle size distribution measurements. A pair of motors and blower pumps provide the necessary 0.5 atmosphere pressure across the type MSA 1106 B glass fiber filter paper to allow a flow rate of 50 cfm. The MSA 1106 B filter paper is designed to trap sub-micrometer particles with a high efficiency; it was chosen to enable a quantitative measurement of airborne radon daughters, one of the principal sources of background signals when radiological surveys are being performed. A venturi section and pressure gauges allow air flow rate measurements so that airborne contaminant concentrations may be quantified. A whole gas sampler capable of sampling a cubic meter of air is mounted inside the aircraft cabin. A nuclear counting system on board the aircraft provides capability for α, β and γ counting of filter paper samples. Design data are presented and types of survey missions which may be served by this system are described

The art of the cover.

Science.gov (United States)

Porter, Nora

2017-07-01

Often, it's difficult to match up our cover artwork with the subjects of our lead articles and special reports. Of necessity, we sometimes turn to pure abstraction. How else to illustrate technical policy articles on subjects such as changing research protocols or informed consent, or abstract ideas like congruence, duality, imbalance, causality? At such times, we have to be pretty creative, and my search for cover art can be long and challenging. In the end, we hope that the reader will make the connection between cover and content. However, at other times, the subject of a lead article or special report overflows with artistic possibilities. © 2017 The Hastings Center.

The Regional Land Cover Monitoring System: Building regional capacity through innovative land cover mapping approaches

Science.gov (United States)

Saah, D.; Tenneson, K.; Hanh, Q. N.; Aekakkararungroj, A.; Aung, K. S.; Goldstein, J.; Cutter, P. G.; Maus, P.; Markert, K. N.; Anderson, E.; Ellenburg, W. L.; Ate, P.; Flores Cordova, A. I.; Vadrevu, K.; Potapov, P.; Phongsapan, K.; Chishtie, F.; Clinton, N.; Ganz, D.

2017-12-01

Earth observation and Geographic Information System (GIS) tools, products, and services are vital to support the environmental decision making by governmental institutions, non-governmental agencies, and the general public. At the heart of environmental decision making is the monitoring land cover and land use change (LCLUC) for land resource planning and for ecosystem services, including biodiversity conservation and resilience to climate change. A major challenge for monitoring LCLUC in developing regions, such as Southeast Asia, is inconsistent data products at inconsistent intervals that have different typologies across the region and are typically made in without stakeholder engagement or input. Here we present the Regional Land Cover Monitoring System (RLCMS), a novel land cover mapping effort for Southeast Asia, implemented by SERVIR-Mekong, a joint NASA-USAID initiative that brings Earth observations to improve environmental decision making in developing countries. The RLCMS focuses on mapping biophysical variables (e.g. canopy cover, tree height, or percent surface water) at an annual interval and in turn using those biophysical variables to develop land cover maps based on stakeholder definitions of land cover classes. This allows for flexible and consistent land cover classifications that can meet the needs of different institutions across the region. Another component of the RLCMS production is the stake-holder engagement through co-development. Institutions that directly benefit from this system have helped drive the development for regional needs leading to services for their specific uses. Examples of services for regional stakeholders include using the RLCMS to develop maps using the IPCC classification scheme for GHG emission reporting and developing custom annual maps as an input to hydrologic modeling/flood forecasting systems. In addition to the implementation of this system and the service stemming from the RLCMS in Southeast Asia, it is

Using ASTER Imagery in Land Use/cover Classification of Eastern Mediterranean Landscapes According to CORINE Land Cover Project

Directory of Open Access Journals (Sweden)

Recep Gundogan

2008-02-01

Full Text Available The satellite imagery has been effectively utilized for classifying land covertypes and detecting land cover conditions. The Advanced Spaceborne Thermal Emissionand Reflection Radiometer (ASTER sensor imagery has been widely used in classificationprocess of land cover. However, atmospheric corrections have to be made by preprocessingsatellite sensor imagery since the electromagnetic radiation signals received by the satellitesensors can be scattered and absorbed by the atmospheric gases and aerosols. In this study,an ASTER sensor imagery, which was converted into top-of-atmosphere reflectance(TOA, was used to classify the land use/cover types, according to COoRdination ofINformation on the Environment (CORINE land cover nomenclature, for an arearepresenting the heterogonous characteristics of eastern Mediterranean regions inKahramanmaras, Turkey. The results indicated that using the surface reflectance data ofASTER sensor imagery can provide accurate (i.e. overall accuracy and kappa values of83.2% and 0.79, respectively and low-cost cover mapping as a part of inventory forCORINE Land Cover Project.

Well-covered graphs and factors

DEFF Research Database (Denmark)

Randerath, Bert; Vestergaard, Preben D.

2006-01-01

A maximum independent set of vertices in a graph is a set of pairwise nonadjacent vertices of largest cardinality α. Plummer defined a graph to be well-covered, if every independent set is contained in a maximum independent set of G. Every well-covered graph G without isolated vertices has a perf...

Percent Wetland Cover

Data.gov (United States)

U.S. Environmental Protection Agency — Wetlands act as filters, removing or diminishing the amount of pollutants that enter surface water. Higher values for percent of wetland cover (WETLNDSPCT) may be...

Covering sources of toxic vapors with foam

International Nuclear Information System (INIS)

Aue, W. P.; Guidetti, F.

2009-01-01

In a case of chemical terrorism, first responders might well be confronted with a liquid source of toxic vapor which keeps spreading out its hazardous contents. With foam as an efficient and simple means, such a source could be covered up in seconds and the spread of vapors mitigated drastically. Once covered, the source could then wait for a longer time to be removed carefully and professionally by a decontamination team. In order to find foams useful for covering up toxic vapor sources, a large set of measurements has been performed in order to answer the following questions: - Which foams could be used for this purpose? - How thick should the foam cover be? - For how long would such a foam cover be effective? - Could the practical application of foam cause a spread of the toxic chemical? The toxic vapors sources included GB, GD and HD. Among the foams were 10 fire fighter foams (e.g. AFFF, protein) and the aqueous decontamination foam CASCAD. Small scale experiments showed that CASCAD is best suited for covering a toxic source; a 10 cm layer of it covers and decontaminates GB. The large scale experiments confirmed that any fire fighter foam is a suitable cover for a longer or shorter period.(author)

Climatological determinants of woody cover in Africa

OpenAIRE

Good, Stephen P.; Caylor, Kelly K.

2011-01-01

Determining the factors that influence the distribution of woody vegetation cover and resolving the sensitivity of woody vegetation cover to shifts in environmental forcing are critical steps necessary to predict continental-scale responses of dryland ecosystems to climate change. We use a 6-year satellite data record of fractional woody vegetation cover and an 11-year daily precipitation record to investigate the climatological controls on woody vegetation cover across the African continent....

Weed Control with Cover Crops in Irrigated Potatoes

Directory of Open Access Journals (Sweden)

G.H. Mehring

2016-01-01

Full Text Available Field experiments at Oakes, ND, USA in 2010 and Carrington, ND, USA in 2011 were conducted to evaluate the potential for cover crops grown in the Northern Great Plains, USA in order to reduce weed emergence and density in irrigated potatoes. Treatments included five cover crop treatments and three cover crop termination treatments. Termination of cover crops was done with glyphosate, disk-till, and roto-till. Cover crop biomass accumulation was greatest for rye/canola and triticale at Oakes, and hairy vetch and hairy vetch/rye at Carrington. Cover crop and termination affected weed control 14, 29, and 51 days after planting (DAP at Oakes. Weed control at Carrington was at least 90% for all cover crop and termination treatments at all three evaluation timings. Marketable yield at Oakes was greater when roto-till was used to terminate the cover crops compared with disk-till or herbicide, which is beneficial for organic systems where herbicides are not used. Marketable yield at Carrington was not affected by cover crop or termination treatments. Results suggest that cover crops can successfully be integrated into irrigated potato production for weed control with yields equal to no cover crop, and with attention to potential mechanical difficulties.

Border Lakes land-cover classification

Science.gov (United States)

Marvin Bauer; Brian Loeffelholz; Doug. Shinneman

2009-01-01

This document contains metadata and description of land-cover classification of approximately 5.1 million acres of land bordering Minnesota, U.S.A. and Ontario, Canada. The classification focused on the separation and identification of specific forest-cover types. Some separation of the nonforest classes also was performed. The classification was derived from multi-...

Cover times of random searches

Science.gov (United States)

Chupeau, Marie; Bénichou, Olivier; Voituriez, Raphaël

2015-10-01

How long must one undertake a random search to visit all sites of a given domain? This time, known as the cover time, is a key observable to quantify the efficiency of exhaustive searches, which require a complete exploration of an area and not only the discovery of a single target. Examples range from immune-system cells chasing pathogens to animals harvesting resources, from robotic exploration for cleaning or demining to the task of improving search algorithms. Despite its broad relevance, the cover time has remained elusive and so far explicit results have been scarce and mostly limited to regular random walks. Here we determine the full distribution of the cover time for a broad range of random search processes, including Lévy strategies, intermittent strategies, persistent random walks and random walks on complex networks, and reveal its universal features. We show that for all these examples the mean cover time can be minimized, and that the corresponding optimal strategies also minimize the mean search time for a single target, unambiguously pointing towards their robustness.

Propagation of captive American kestrels

Science.gov (United States)

Porter, Ron; Wiemeyer, Stanley N.

1970-01-01

A colony of kestrels (Palco sparverius) was established at the Patuxent Wildlife Research Center in 1964 in connection with work on pesticides. The kestrels were acquired from the wild, both as nestlings and as full-grown birds, and were housed in several rows of outdoor pens. Each 50 x 20 ft pen was covered with wire netting and had its long sides in common with adjacent pens. During the first two reproductive seasons, untreated parent birds (dosed birds are not included in this paper) ate eggs and young. Cannibalism virtually ceased after the diet was changed from ground beef or horsemeat supplemented with liver, vitamins, and minerals to one containing a finely ground mixture of laboratory rodents, chicken heads, skinned chicken necks, and supplements; hatching success thereafter generally equalled that of a wild population. In 1967, 16 pairs of untreated hawks (3-year-old females) laid clutches averaging 4.9 eggs, hatched 88 percent of their eggs, and fledged 88 percent of their young. In 1968, 10 pairs of this group (4-year-old females) laid clutches averaging 4.9 eggs, hatched 51 percent of their eggs, and fledged 85 percent of their young. Nine yearling pairs (hatched in captivity) laid clutches in 1968 averaging 5.1 eggs, hatched 87 percent of their eggs, and fledged all of their young.

Factors influencing radon attenuation by tailing covers

International Nuclear Information System (INIS)

Silker, W.B.; Rogers, V.C.

1981-07-01

The US NRC, in its Generic Environmental Impact Statement on uranium milling has specified that the radon flux escaping a uranium mill tailings pile will be reduced to pCi/m 2 s by application of covering layers of soils and clays. These covers present a radon diffusion barrier, which sufficiently increases the time required for radon passage from the tailings to the atmosphere to allow for decay of 222 Rn within the cover. The depth of cover necessary to reduce the escaping radon flux to the prescribed level is to be determined by calculation, and requires precise knowledge of the radon diffusion coefficient in the covering media. A Radon Attenuation Test Facility was developed to determine rates of radon diffusion through candidate cover materials. This paper describes this facility and its application for determining the influence of physical properties of the soil column on the radon diffusion coefficient

Structural integrity assessment of HANARO pool cover

International Nuclear Information System (INIS)

Ryu, Jeong Soo

2001-11-01

This report is for the seismic analysis and the structural integrity evaluation of HANARO Pool Cover in accordances with the requirement of the Technical Specification for Seismic Analysis of HANARO Pool Cover. For performing the seismic analysis and evaluating the structural integrity for HANARO Pool Cover, the finite element analysis model using ANSYS 5.7 was developed and the dynamic characteristics were analyzed. The seismic response spectrum analyses of HANARO Pool Cover under the design floor response spectrum loads of OBE and SSE were performed. The analysis results show that the stress values in HANARO Pool Cover for the seismic loads are within the ASME Code limits. It is also confirmed that the fatigue usage factor is less than 1.0. Therefore any damage on structural integrity is not expected when an HANARO Pool Cover is installed in the upper part of the reactor pool

On Covering Approximation Subspaces

Directory of Open Access Journals (Sweden)

Xun Ge

2009-06-01

Full Text Available Let (U';C' be a subspace of a covering approximation space (U;C and X⊂U'. In this paper, we show that and B'(X⊂B(X∩U'. Also, iff (U;C has Property Multiplication. Furthermore, some connections between outer (resp. inner definable subsets in (U;C and outer (resp. inner definable subsets in (U';C' are established. These results answer a question on covering approximation subspace posed by J. Li, and are helpful to obtain further applications of Pawlak rough set theory in pattern recognition and artificial intelligence.

Post-hatching development of mitochondrial function, organ mass and metabolic rate in two ectotherms, the American alligator (Alligator mississippiensis and the common snapping turtle (Chelydra serpentina

Directory of Open Access Journals (Sweden)

Sarah K. G. Sirsat

2016-04-01

Full Text Available The ontogeny of endothermy in birds is associated with disproportionate growth of thermogenic organs and increased mitochondrial oxidative capacity. However, no similar study has been made of the development of these traits in ectotherms. For comparison, we therefore investigated the metabolism, growth and muscle mitochondrial function in hatchlings of a turtle and a crocodilian, two ectotherms that never develop endothermy. Metabolic rate did not increase substantially in either species by 30 days post-hatching. Yolk-free body mass and heart mass did not change through 30 days in alligators and heart mass was a constant proportion of body mass, even after 1 year. Yolk-free body mass and liver mass grew 36% and 27%, respectively, in turtles during the first 30 days post-hatch. The mass-specific oxidative phosphorylation capacity of mitochondria, assessed using permeabilized muscle fibers, increased by a non-significant 47% in alligator thigh and a non-significant 50% in turtle thigh over 30 days, but did not increase in the heart. This developmental trajectory of mitochondrial function is slower and shallower than that previously observed in ducks, which demonstrate a 90% increase in mass-specific oxidative phosphorylation capacity in thigh muscles over just a few days, a 60% increase in mass-specific oxidative phosphorylation capacity of the heart over a few days, and disproportionate growth of the heart and other organs. Our data thus support the hypothesis that these developmental changes in ducks represent mechanistic drivers for attaining endothermy.

Post-hatching development of mitochondrial function, organ mass and metabolic rate in two ectotherms, the American alligator (Alligator mississippiensis) and the common snapping turtle (Chelydra serpentina).

Science.gov (United States)

Sirsat, Sarah K G; Sirsat, Tushar S; Price, Edwin R; Dzialowski, Edward M

2016-04-15

The ontogeny of endothermy in birds is associated with disproportionate growth of thermogenic organs and increased mitochondrial oxidative capacity. However, no similar study has been made of the development of these traits in ectotherms. For comparison, we therefore investigated the metabolism, growth and muscle mitochondrial function in hatchlings of a turtle and a crocodilian, two ectotherms that never develop endothermy. Metabolic rate did not increase substantially in either species by 30 days post-hatching. Yolk-free body mass and heart mass did not change through 30 days in alligators and heart mass was a constant proportion of body mass, even after 1 year. Yolk-free body mass and liver mass grew 36% and 27%, respectively, in turtles during the first 30 days post-hatch. The mass-specific oxidative phosphorylation capacity of mitochondria, assessed using permeabilized muscle fibers, increased by a non-significant 47% in alligator thigh and a non-significant 50% in turtle thigh over 30 days, but did not increase in the heart. This developmental trajectory of mitochondrial function is slower and shallower than that previously observed in ducks, which demonstrate a 90% increase in mass-specific oxidative phosphorylation capacity in thigh muscles over just a few days, a 60% increase in mass-specific oxidative phosphorylation capacity of the heart over a few days, and disproportionate growth of the heart and other organs. Our data thus support the hypothesis that these developmental changes in ducks represent mechanistic drivers for attaining endothermy. © 2016. Published by The Company of Biologists Ltd.

Mapping Forest Cover and Forest Cover Change with Airborne S-Band Radar

Directory of Open Access Journals (Sweden)

Ramesh K. Ningthoujam

2016-07-01

Full Text Available Assessments of forest cover, forest carbon stocks and carbon emissions from deforestation and degradation are increasingly important components of sustainable resource management, for combating biodiversity loss and in climate mitigation policies. Satellite remote sensing provides the only means for mapping global forest cover regularly. However, forest classification with optical data is limited by its insensitivity to three-dimensional canopy structure and cloud cover obscuring many forest regions. Synthetic Aperture Radar (SAR sensors are increasingly being used to mitigate these problems, mainly in the L-, C- and X-band domains of the electromagnetic spectrum. S-band has not been systematically studied for this purpose. In anticipation of the British built NovaSAR-S satellite mission, this study evaluates the benefits of polarimetric S-band SAR for forest characterisation. The Michigan Microwave Canopy Scattering (MIMICS-I radiative transfer model is utilised to understand the scattering mechanisms in forest canopies at S-band. The MIMICS-I model reveals strong S-band backscatter sensitivity to the forest canopy in comparison to soil characteristics across all polarisations and incidence angles. Airborne S-band SAR imagery over the temperate mixed forest of Savernake Forest in southern England is analysed for its information content. Based on the modelling results, S-band HH- and VV-polarisation radar backscatter and the Radar Forest Degradation Index (RFDI are used in a forest/non-forest Maximum Likelihood classification at a spatial resolution of 6 m (70% overall accuracy, κ = 0.41 and 20 m (63% overall accuracy, κ = 0.27. The conclusion is that S-band SAR such as from NovaSAR-S is likely to be suitable for monitoring forest cover and its changes.

Land Use and Land Cover - MO 2015 Silver Land Cover (GDB)

Data.gov (United States)

NSGIC State | GIS Inventory — MoRAP produced and integrated data to map land cover and wetlands for the Upper Silver Creek Watershed in Illinois. LiDAR elevation and vegetation height information...

Land Use and Land Cover - MO 2015 Meramec Land Cover (GDB)

Data.gov (United States)

NSGIC State | GIS Inventory — MoRAP produced and integrated data to map land cover and wetlands for the Meramec River bottomland in Missouri. LiDAR elevation and vegetation height information and...

Review on the acute Daphnia magna toxicity test – Evaluation of the sensitivity and the precision of assays performed with organisms from laboratory cultures or hatched from dormant eggs

Directory of Open Access Journals (Sweden)

G. Persoone

2009-08-01

performance of the assays.One of these microbiotests is the Daphtoxkit F magna, which is currently used in many laboratories worldwide for research as well as for toxicity monitoring purposes.The microbiotest technology has several advantages in comparison to the “traditional” tests based on laboratory cultures, especially its independence of the stock culturing burden. However, the acceptance (or possible non-acceptance of performing assays with test organisms obtained from “dormant eggs” should be clearly dictated by the “sensitivity” and “precision” criteria of the former assays in comparison to the latter.The first part of this review therefore thoroughly reviews the scientific literature and of data obtained from various laboratories for assays performed with either D. magna test organisms obtained from lab cultures or hatched from dormant eggs.Attention has focused on data of quality control tests performed on reference chemicals, and in particular on potassium dichromate (K2Cr2O7 for which an acceptability range of 0.6–2.1 mg·L–1 has been set in ISO standard 6341 for the 24 h EC50 of the acute D. magna assay.Mean EC50s, standard deviations and variation coefficients were calculated from the collected data, all of which are presented in tables and figures and discussed in detail.The major conclusions drawn from the analysis of the large number of quality control (QC data on the acute D. magna toxicity test are that :(1 Virtually all results from assays performed with Daphnias taken from lab cultures or with Daphnia microbiotests are within the acceptability range set by ISO standard 6341 for the reference chemical potassium dichromate.(2 The mean 24 h EC50s of the Daphnia microbiotests performed in different laboratories are within the range of the mean EC50s of the assays based on lab cultures, and the variation coefficients (20 to 30% are similar.(3 The precision – in terms of the long term in house variability – of the quality control Daphnia

Updating the 2001 National Land Cover Database land cover classification to 2006 by using Landsat imagery change detection methods

Science.gov (United States)

Xian, George; Homer, Collin G.; Fry, Joyce

2009-01-01

The recent release of the U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001, which represents the nation's land cover status based on a nominal date of 2001, is widely used as a baseline for national land cover conditions. To enable the updating of this land cover information in a consistent and continuous manner, a prototype method was developed to update land cover by an individual Landsat path and row. This method updates NLCD 2001 to a nominal date of 2006 by using both Landsat imagery and data from NLCD 2001 as the baseline. Pairs of Landsat scenes in the same season in 2001 and 2006 were acquired according to satellite paths and rows and normalized to allow calculation of change vectors between the two dates. Conservative thresholds based on Anderson Level I land cover classes were used to segregate the change vectors and determine areas of change and no-change. Once change areas had been identified, land cover classifications at the full NLCD resolution for 2006 areas of change were completed by sampling from NLCD 2001 in unchanged areas. Methods were developed and tested across five Landsat path/row study sites that contain several metropolitan areas including Seattle, Washington; San Diego, California; Sioux Falls, South Dakota; Jackson, Mississippi; and Manchester, New Hampshire. Results from the five study areas show that the vast majority of land cover change was captured and updated with overall land cover classification accuracies of 78.32%, 87.5%, 88.57%, 78.36%, and 83.33% for these areas. The method optimizes mapping efficiency and has the potential to provide users a flexible method to generate updated land cover at national and regional scales by using NLCD 2001 as the baseline.

The evolution of size of the uropygial gland: mutualistic feather mites and uropygial secretion reduce bacterial loads of eggshells and hatching failures of European birds.

Science.gov (United States)

Soler, J J; Peralta-Sánchez, J M; Martín-Platero, A M; Martín-Vivaldi, M; Martínez-Bueno, M; Møller, A P

2012-09-01

Potentially, pathogenic bacteria are one of the main infective agents against which a battery of chemical and physical barriers has evolved in animals. Among these are the secretions by the exocrine uropygial gland in birds. The antimicrobial properties of uropygial secretions may prevent colonization and growth of microorganisms on feathers, skin and eggshells. However, uropygial gland secretions also favour the proliferation of feather mites that feed on secretions and microorganisms living on feathers that would otherwise reach eggshells during incubation if not consumed by feather mites. Therefore, at the interspecific level, uropygial gland size (as an index of volume of uropygial secretion) should be positively related to eggshell bacterial load (i.e. the risk of egg infection), whereas eggshell bacterial loads may be negatively related to abundance of feather mites eating bacteria. Here, we explore these previously untested predictions in a comparative framework using information on eggshell bacterial loads, uropygial gland size, diversity and abundance of feather mites and hatching success of 22 species of birds. The size of the uropygial gland was positively related to eggshell bacterial loads (mesophilic bacteria and Enterobacteriaceae), and bird species with higher diversity and abundance of feather mites harboured lower bacterial density on their eggshells (Enterococcus and Staphylococcus), in accordance with the hypothesis. Importantly, eggshell bacterial loads of mesophilic bacteria, Enterococcus and Enterobacteriaceae were negatively associated with hatching success, allowing us to interpret these interspecific relationships in a functional scenario, where both uropygial glands and mutualistic feather mites independently reduce the negative effects of pathogenic bacteria on avian fitness. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

1990 Kansas Land Cover Patterns Update

Data.gov (United States)

Kansas Data Access and Support Center — In 2008, an update of the 1990 Kansas Land Cover Patterns (KLCP) database was undertaken. The 1990 KLCP database depicts 10 general land cover classes for the State...

Fuel exchanger for nuclear ships

International Nuclear Information System (INIS)

Suda, Koji; Kanbara, Takahisa; Watanabe, Masaharu.

1984-01-01

Purpose: To prevent enviromental contamination landing radioactive materials from the inside of a ship. Constitution: A provisional cabin having a shape covering a reactor hatch and a hatch cover is disposed on the upper deck of a ship body. A ceiling shutter is disposed to the cabin. A protection cylinder having a shutter and a filter fan is attached on the cabin. Materials to be discharged out of the ship are transported to a fuel exchange tower on land by using a crane while being contained in the protection cylinder with the shutter being closed. The protection cylinder is connected by means of a wire rope to a loop-wheel machine which disposed on the trolly of a crane. While the bellows through which the suspending wire for the discharged products passes is perforated, since the inside of the cylinder is depressurized by a filter fan, there is no air leakage through the perforation to the outside. (Ikeda, J.)

Fuel exchanger for nuclear ships

Energy Technology Data Exchange (ETDEWEB)

Suda, Koji; Kanbara, Takahisa; Watanabe, Masaharu

1984-11-29

To prevent enviromental contamination by radioactive materials from the inside of a ship a provisional cabin having a shape covering a reactor hatch and a hatch cover is disposed on the upper deck of a ship body. A ceiling shutter is disposed to the cabin. A protection cylinder having a shutter and a filter fan is attached on the cabin. Materials to be discharged out of the ship are transported to a fuel exchange tower on land by using a crane while being contained in the protection cylinder with the shutter being closed. The protection cylinder is connected by means of a wire rope to a loop-wheel machine which is disposed on the trolly of a crane. While the bellows through which the suspending wire for the discharged products passes is perforated, since the inside of the cylinder is depressurized by a filter fan, there is no air leakage through the perforation to the outside.

VT National Land Cover Dataset - 2001

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) The NLCD2001 layer available from VCGI is a subset of the the National Land Cover Database 2001 land cover layer for mapping zone 65 was produced...

Weed Control with Cover Crops in Irrigated Potatoes

OpenAIRE

G.H. Mehring; J.E. Stenger; H.M. Hatterman-Valenti

2016-01-01

Field experiments at Oakes, ND, USA in 2010 and Carrington, ND, USA in 2011 were conducted to evaluate the potential for cover crops grown in the Northern Great Plains, USA in order to reduce weed emergence and density in irrigated potatoes. Treatments included five cover crop treatments and three cover crop termination treatments. Termination of cover crops was done with glyphosate, disk-till, and roto-till. Cover crop biomass accumulation was greatest for rye/canola and triticale at Oakes, ...

Spatio-temporal change in forest cover and carbon storage considering actual and potential forest cover in South Korea.

Science.gov (United States)

Nam, Kijun; Lee, Woo-Kyun; Kim, Moonil; Kwak, Doo-Ahn; Byun, Woo-Hyuk; Yu, Hangnan; Kwak, Hanbin; Kwon, Taesung; Sung, Joohan; Chung, Dong-Jun; Lee, Seung-Ho

2015-07-01

This study analyzes change in carbon storage by applying forest growth models and final cutting age to actual and potential forest cover for six major tree species in South Korea. Using National Forest Inventory data, the growth models were developed to estimate mean diameter at breast height, tree height, and number of trees for Pinus densiflora, Pinus koraiensis, Pinus rigida, Larix kaempferi, Castanea crenata and Quercus spp. stands. We assumed that actual forest cover in a forest type map will change into potential forest covers according to the Hydrological and Thermal Analogy Groups model. When actual forest cover reaches the final cutting age, forest volume and carbon storage are estimated by changed forest cover and its growth model. Forest volume between 2010 and 2110 would increase from 126.73 to 157.33 m(3) hm(-2). Our results also show that forest cover, volume, and carbon storage could abruptly change by 2060. This is attributed to the fact that most forests are presumed to reach final cutting age. To avoid such dramatic change, a regeneration and yield control scheme should be prepared and implemented in a way that ensures balance in forest practice and yield.

Babes and boobs? analysis of JAMA cover art.

Science.gov (United States)

Clark, J P

To determine the representation of the sexes in JAMA cover art. Review of 50 consecutive issues. JAMA, March 1997-March 1998. Numbers and nature of covers portraying men and women. Of the 50 covers, 34 depicted humans. 15 depicted women, 13 men, and 6 were of mixed or indeterminate sex. 11 pictures of women included a child and five included nudity. One cover showed a man with a child (not as a father) and none depicted nudity. Men were depicted exclusively in authoritative roles. Much of the cover art gives strong messages about sexual stereotypes that are inappropriate in modern society. JAMA should consider reviewing its policy for choosing cover art.

Covering of the electric power service

International Nuclear Information System (INIS)

Unidad de Planeacion Minero Energetica, UPME

2000-01-01

In this article it is sought to deepen more in the topic of the covering of the electric power service, especially in the related with the mechanisms that could facilitate their amplification. In the new market outline, in the one that the participation of the agents is encouraged in all the activities of the chain of services in which the state is not direct lender of the same one, it is confused the form like a covering will be achieved that is of agreement with the goals that intend in the national plan of development and in the sub sectorial plans. Although the rules of the market one comes consolidating, the process of linking of the private capital, especially in the distribution activity, it evidences the importance of to settle down and to define responsibilities and explicit mechanisms in the topic of expansion of the covering. A first interpretation of the ruled indicates the obligation of the state of extending the covering to 100% and of assuming the projects that don't undertake the matters. This would be the reading from the traditional mentality. However, the regulation of you public services of electricity don't demand a total covering, but rather it covers to the users that have the capacity to assume, with their own resources, the efficient costs of benefit. The service will also be lent to residential users that don't have payment capacity, when there are contribution resources or fiscal resources for subsidiary

Towards realistic Holocene land cover scenarios: integration of archaeological, palynological and geomorphological records and comparison to global land cover scenarios.

Science.gov (United States)

De Brue, Hanne; Verstraeten, Gert; Broothaerts, Nils; Notebaert, Bastiaan

2016-04-01

Accurate and spatially explicit landscape reconstructions for distinct time periods in human history are essential for the quantification of the effect of anthropogenic land cover changes on, e.g., global biogeochemical cycles, ecology, and geomorphic processes, and to improve our understanding of interaction between humans and the environment in general. A long-term perspective covering Mid and Late Holocene land use changes is recommended in this context, as it provides a baseline to evaluate human impact in more recent periods. Previous efforts to assess the evolution and intensity of agricultural land cover in past centuries or millennia have predominantly focused on palynological records. An increasing number of quantitative techniques has been developed during the last two decades to transfer palynological data to land cover estimates. However, these techniques have to deal with equifinality issues and, furthermore, do not sufficiently allow to reconstruct spatial patterns of past land cover. On the other hand, several continental and global databases of historical anthropogenic land cover changes based on estimates of global population and the required agricultural land per capita have been developed in the past decennium. However, at such long temporal and spatial scales, reconstruction of past anthropogenic land cover intensities and spatial patterns necessarily involves many uncertainties and assumptions as well. Here, we present a novel approach that combines archaeological, palynological and geomorphological data for the Dijle catchment in the central Belgium Loess Belt in order to arrive at more realistic Holocene land cover histories. Multiple land cover scenarios (> 60.000) are constructed using probabilistic rules and used as input into a sediment delivery model (WaTEM/SEDEM). Model outcomes are confronted with a detailed geomorphic dataset on Holocene sediment fluxes and with REVEALS based estimates of vegetation cover using palynological data from

The National Land Cover Database

Science.gov (United States)

Homer, Collin G.; Fry, Joyce A.; Barnes, Christopher A.

2012-01-01

The National Land Cover Database (NLCD) serves as the definitive Landsat-based, 30-meter resolution, land cover database for the Nation. NLCD provides spatial reference and descriptive data for characteristics of the land surface such as thematic class (for example, urban, agriculture, and forest), percent impervious surface, and percent tree canopy cover. NLCD supports a wide variety of Federal, State, local, and nongovernmental applications that seek to assess ecosystem status and health, understand the spatial patterns of biodiversity, predict effects of climate change, and develop land management policy. NLCD products are created by the Multi-Resolution Land Characteristics (MRLC) Consortium, a partnership of Federal agencies led by the U.S. Geological Survey. All NLCD data products are available for download at no charge to the public from the MRLC Web site: http://www.mrlc.gov.

Incubação artificial dos ovos e processo de eclosão em Trachemys dorbignyi (Duméril & Bibron (Reptilia, Testudines, Emydidae Artificial egg incubation and hatching proccess in Trachemys dorbignyi (Duméril & Bibron (Reptilia, Testudimes, Emydidae

Directory of Open Access Journals (Sweden)

Flavio de Barros Molina

1998-01-01

Full Text Available Artificial incubation of 558 eggs from 70 clutches of Trachemys dorbignyi (Duméril & Bibron, 1835 were performed at São Paulo Zoo during 1992 and 1993. Hatching occurred when eggs were incubated between 25 and 31.5oC. Incubation time varied from 54 (at 31.5oC to 120 days (at 25oC, similarly to Trachemys scripla sspp. Hatchling used the caruncle to made small incisions in the egg shell, latter enlarged by movements of the head and forefeet. Hatching usually lasted from one to two days. Newborn's carapace and plastron showed their natural form few hours after the emergence from the egg shell. During the third or fourth week, caruncle usually disappeared, and yolk sac was completely absorbed. Average (x±sd measures of newborn were 3.55±0.18cm of carapace length, 3.35±0.17cm of plastron length, and 10.73±1.36g of weight.

Land cover changes in central Sonora Mexico

Science.gov (United States)

Diego Valdez-Zamudio; Alejandro Castellanos-Villegas; Stuart Marsh

2000-01-01

Remote sensing techniques have been demonstrated to be very effective tools to help detect, analyze, and evaluate land cover changes in natural areas of the world. Changes in land cover can generally be attributed to either natural or anthropogenic forces. Multitemporal satellite imagery and airborne videography were used to detect, analyze, and evaluate land cover...

On the Structure of Covers of Sofic Shifts

DEFF Research Database (Denmark)

Johansen, Rune

2011-01-01

A canonical cover generalizing the left Fischer cover to arbitrary sofic shifts is introduced and used to prove that the left Krieger cover and the past set cover of a sofic shift can be divided into natural layers. These results are used to find the range of a flow-invariant and to investigate t...

AsMA journal covers, a history.

Science.gov (United States)

Day, Pamela C

2014-01-01

The cover of our journal has changed quite often over the years. As we look forward to changing the name and design of the journal, it seems appropriate to reflect on the previous journal titles and covers. A brief history follows.

On the complexity of container stowage planning problems

DEFF Research Database (Denmark)

Tierney, Kevin; Pacino, Dario; Jensen, Rune Møller

2014-01-01

The optimization of container ship and depot operations embeds the kk-shift problem, in which containers must be stowed in stacks such that at most kk containers must be removed in order to reach containers below them. We first solve an open problem introduced by Avriel et al. (2000) by showing...... that changing from uncapacitated to capacitated stacks reduces the complexity of this problem from NP-complete to polynomial. We then examine the complexity of the current state-of-the-art abstraction of container ship stowage planning, wherein containers and slots are grouped together. To do this, we define...... the hatch overstow problem, in which a set of containers are placed on top of the hatches of a container ship such that the number of containers that are stowed on hatches that must be accessed is minimized. We show that this problem is NP-complete by a reduction from the set-covering problem, which means...

Physical, Chemical, Ecological, and Age Data and Trench Logs from Surficial Deposits at Hatch Point, Southeastern Utah

Science.gov (United States)

Goldstein, Harland L.; Miller, Mark E.; Yount, James C.; Reheis, Marith C.; Reynolds, Richard L.; Belnap, Jayne; Lamothe, Paul J.; McGeehan, John P.

2009-01-01

This report presents data and describes the methodology for physical, chemical and ecological measurements of sediment, soil, and vegetation, as well as age determinations of surficial deposits at Hatch Point, Canyon Rims area, Colorado Plateau, southeastern Utah. The results presented in this report support a study that examines geomorphic and soil factors that may influence boundaries between shrubland and grassland ecosystems in the study area. Shrubland ecosystems dominated by sagebrush (Artemisia tridentata) and grassland ecosystems dominated by native perennial grasses (for example, Hilaria jamesii and Sporabolis sp.) are high-priority conservation targets for the Federal Bureau of Land Management (BLM) and other resource managers because of their diversity, productivity, and vital importance as wildlife habitat. These ecosystems have been recognized as imperiled on a regional scale since at least the mid-1990s due to habitat loss (type conversions), land-use practices, and invasive exotic plants. In the Intermountain West, the exotic annual cheatgrass (Bromus tectorum) is recognized as one of the most pervasive and serious threats to the health of native sagebrush and grassland ecosystems through effects on fire regimes and resource conditions experienced by native species.

Modeling percent tree canopy cover: a pilot study

Science.gov (United States)

John W. Coulston; Gretchen G. Moisen; Barry T. Wilson; Mark V. Finco; Warren B. Cohen; C. Kenneth Brewer

2012-01-01

Tree canopy cover is a fundamental component of the landscape, and the amount of cover influences fire behavior, air pollution mitigation, and carbon storage. As such, efforts to empirically model percent tree canopy cover across the United States are a critical area of research. The 2001 national-scale canopy cover modeling and mapping effort was completed in 2006,...

Infinity-Norm Permutation Covering Codes from Cyclic Groups

OpenAIRE

Karni, Ronen; Schwartz, Moshe

2017-01-01

We study covering codes of permutations with the $\\ell_\\infty$-metric. We provide a general code construction, which uses smaller building-block codes. We study cyclic transitive groups as building blocks, determining their exact covering radius, and showing linear-time algorithms for finding a covering codeword. We also bound the covering radius of relabeled cyclic transitive groups under conjugation.

Productive Performance of Broiler after Pre and /or Post-hatching Injection of Thyroid and Growth Hormones

International Nuclear Information System (INIS)

Gamal, M.H.; El-Gendi, G.M.

2003-01-01

A total number of 1340 eggs from Arbor Acres parent breed were used in this study. Eggs were divided into two division according to the incubation relative humidity (48% and 52%). Eggs of each division were than subdivided into ten groups, eggs of 1 st , 2 nd and 3 rd groups were injected with 0.05, 0.10 and 0.15μg eltroxin, respectively, those of the 4 th , 5 th and 6 th groups were injected with 0.05, 0.10 and 0.15 mg Carbimazole, respectively, while eggs of the 7 th , 8 th and 9 th groups were injected with 0.005, 0.02 and 0.04 I.U. growth hormone, respectively. Eggs of the 10 th group were injected with distilled water and used as control group. Each group was divided into two divisions, eggs of the first division were injected just before incubation (into the air cell) and those of the second division were injected at the 9 th day of incubation period (into the embryonic allantoic cavity). A total number of 960 hatched chicks were randomly selected (24 chicks of cach group), wing banded, individually weighted, vaccinated and standard conditions of management, environment, hygiene and nutrition

The outcome of assisted hatching and defragmentation in patients with poor quality embryos on IVF outcome

Directory of Open Access Journals (Sweden)

Ahmet Zeki Işık

2013-09-01

Full Text Available Objective: To evaluate the effects of assisted hatching in combination with defragmentation applied to day 3 poor quality human embryos, on implantation and pregnancy rates. Materials and Methods: A retrospective analysis was performed in patients (n=168 of all ages with no good quality transferable embryos (Veeck classification embryos >grade 1 and/or >10% fragmentation. The first group was consisted of cycles in which mAHA was performed to all transferred grade 2 embryos. The second group included transfer cycles where all the embryos were highly fragmented (between 10-50% fragmentations, grade 3 and aAHA and microsurgical fragment removal were applied to all of them. Results: In first group positive βhCG was 33%, clinical pregnancy (fetal heart beat rate was 27% and implantation rate was 11,28%. These rates were 37, 1%; 28, 8% and %16,19 respectively in the aAHA plus defragmentation group. In cases over 35 years of age in aAHA plus defragmentation group acceptable implantation (14,46% and clinical pregnancy (31,58% rates were achieved. Conclusion: In patients with no good quality transferable embryos AHA combined with defragmentation can be utilised with acceptable success rates in laboratories where there are experienced personnel available for this procedure otherwise only AHA can be the best option.

40 CFR 63.941 - Definitions.

Science.gov (United States)

2010-07-01

... another subpart that references the use of this subpart, then the definition in this subpart shall take precedence when implementing this subpart. Closure device means a cap, hatch, lid, plug, seal, valve, or... a surface impoundment cover when the device is secured in the closed position. Closure devices...

Liquidity in Government versus Covered Bond Markets

DEFF Research Database (Denmark)

Dick-Nielsen, Jens; Gyntelberg, Jacob; Sangill, Thomas

We present findings on the secondary market liquidity of government and covered bonds in Denmark before, during and after the 2008 financial crisis. The analysis focuses on wholesale trading in the two markets and is based on a complete transaction level dataset covering November 2007 until end...... 2011. Overall, our findings suggest that Danish benchmark covered bonds by and large are as liquid as Danish government bonds - including in periods of market stress. Before the financial crisis of 2008, government bonds were slightly more liquid than covered bonds. During the crisis, trading continued...... in both markets but the government bond market experienced a brief but pronounced decline in market liquidity while liquidity in the covered bond market was more robust - partly reflective of a number of events as well as policy measures introduced in the autumn of 2008. After the crisis, liquidity...

49 CFR 633.11 - Covered projects.

Science.gov (United States)

2010-10-01

... 49 Transportation 7 2010-10-01 2010-10-01 false Covered projects. 633.11 Section 633.11..., DEPARTMENT OF TRANSPORTATION PROJECT MANAGEMENT OVERSIGHT Project Management Oversight Services § 633.11 Covered projects. The Administrator may contract for project management oversight services when the...

Fuel element transport container with a removable cover

International Nuclear Information System (INIS)

Dannehl, G.; Fink, W.; Haenle, G.

1980-01-01

The cover of the fuel element transport container is removably fixed with screws on a flange as mechanical loads have to be expected during the transfer to the disposal plant. A ring-shaped or star-shaped clamping device grips over the cover. It has a clamp claw to lock the cover and permits unscrewing without unlocking the cover. (DG) [de

Moisture content analysis of covered uranium mill tailings

International Nuclear Information System (INIS)

Mayer, D.W.; Beedlow, P.A.; Cadwell, L.L.

1981-12-01

The use of vegetation and rock covers to stabilize uranium mill tailings cover systems is being investigated by Pacific Northwest Laboratory. A modeling study of moisture movement through the tailings and cover layers was initiated to determine the effect of the stabilizing techniques. The cover system was simulated under climatic conditions occurring at Grand Junction, Colorado. The cover consisted of a layer of wet clay/gravel mix followed by a capillary barrier of washed rock and a surface layer of fill soil. Vegetation and rock were used to stabilize the surface layer. The simulation yielded moisture content and moisture storage values for the tailings and cover system along with information about moisture losses due to evaporation, transpiration, and drainage. The study demonstrates that different surface stabilization treatments lead to different degrees of moisture retention in the covered tailings pile. The evapotranspiration from vegetation can result in a relatively stable moisture content. Rock covers, however, may cause drainage to occur because they reduce evaporation and lead to a subsequent increase in moisture content. It is important to consider these effects when designing a surface stabilization treatment. Drainage may contribute to a groundwater pollution problem. A surface treatment that allows the cover system to dry out can increase the risk of atmospheric contamination through elevated radon emission rates

Establishment of the fatty acid profile of the brain of the king penguin (Aptenodytes patagonicus) at hatch: effects of a yolk that is naturally rich in n-3 polyunsaturates.

Science.gov (United States)

Speake, Brian K; Decrock, Frederic; Surai, Peter F; Wood, Nicholas A R; Groscolas, René

2003-01-01

Because the yolk lipids of the king penguin (Aptenodytes patagonicus) contain the highest concentrations of long-chain n-3 polyunsaturated fatty acids yet reported for an avian species, the consequences for the establishment of the brain's fatty acid profile in the embryo were investigated. To place the results in context, the fatty acid compositions of yolk lipid and brain phospholipid of the king penguin were compared with those from three other species of free-living birds. The proportions of docosahexaenoic acid (22:6n-3; DHA) in the total lipid of the initial yolks for the Canada goose (Branta canadensis), mallard (Anas platyrhynchos), moorhen (Gallinula chloropus), and king penguin were (% w/w of fatty acids) 1.0+/-0.1, 1.9+/-0.2, 3.3+/-0.1, and 5.9+/-0.2, respectively. The respective concentrations of DHA (% w/w of phospholipid fatty acids) in brains of the newly hatched chicks of these same species were 18.5+/-0.2, 19.6+/-0.7, 16.9+/-0.4, and 17.6+/-0.1. Thus, the natural interspecies diversity in yolk fatty acid profiles does not necessarily produce major differences in the DHA content of the developing brain. Only about 1% of the amount of DHA initially present in the yolk was recovered in the brain of the penguin at hatch. There was no preferential uptake of DHA from the yolk during development of the king penguin.

Climatological determinants of woody cover in Africa.

Science.gov (United States)

Good, Stephen P; Caylor, Kelly K

2011-03-22

Determining the factors that influence the distribution of woody vegetation cover and resolving the sensitivity of woody vegetation cover to shifts in environmental forcing are critical steps necessary to predict continental-scale responses of dryland ecosystems to climate change. We use a 6-year satellite data record of fractional woody vegetation cover and an 11-year daily precipitation record to investigate the climatological controls on woody vegetation cover across the African continent. We find that-as opposed to a relationship with only mean annual rainfall-the upper limit of fractional woody vegetation cover is strongly influenced by both the quantity and intensity of rainfall events. Using a set of statistics derived from the seasonal distribution of rainfall, we show that areas with similar seasonal rainfall totals have higher fractional woody cover if the local rainfall climatology consists of frequent, less intense precipitation events. Based on these observations, we develop a generalized response surface between rainfall climatology and maximum woody vegetation cover across the African continent. The normalized local gradient of this response surface is used as an estimator of ecosystem vegetation sensitivity to climatological variation. A comparison between predicted climate sensitivity patterns and observed shifts in both rainfall and vegetation during 2009 reveals both the importance of rainfall climatology in governing how ecosystems respond to interannual fluctuations in climate and the utility of our framework as a means to forecast continental-scale patterns of vegetation shifts in response to future climate change.

Replacing fallow by cover crops: economic sustainability

Science.gov (United States)

Gabriel, José Luis; Garrido, Alberto; Quemada, Miguel

2013-04-01

Replacing fallow by cover crops in intensive fertilized systems has been demonstrated as an efficient tool for reducing nitrate leaching. However, despite the evident environmental services provided and the range of agronomic benefits documented in the literature, farmers' adoption of this new technology is still limited because they are either unwilling or unable, although adoption reluctance is frequently rooted in low economic profitability, low water se efficiency or poor knowledge. Economic analyses permit a comparison between the profit that farmers obtain from agricultural products and the cost of adopting specific agricultural techniques. The goal of this study was to evaluate the economic impact of replacing the usual winter fallow with cover crops (barley (Hordeum vulgare L., cv. Vanessa), vetch (Vicia villosa L., cv. Vereda) and rapeseed (Brassica napus L., cv. Licapo)) in irrigated maize systems and variable Mediterranean weather conditions using stochastic Monte-Carlo simulations of key farms' financial performance indicators. The three scenarios studied for each cover crop were: i) just leaving the cover crop residue in the ground, ii) leaving the cover crop residue but reduce following maize fertilization according to the N available from the previous cover crop and iii) selling the cover crop residue for animal feeding. All the scenarios were compared with respect to a typical maize-fallow rotation. With observed data from six different years and in various field trials, looking for different weather conditions, probability distribution functions of maize yield, cover crop biomass production and N fertilizer saving was fitted. Based in statistical sources maize grain price, different forage prices and the cost of fertilizer were fitted to probability distribution functions too. As result, introducing a cover crop involved extra costs with respect to fallow as the initial investment, because new seed, herbicide or extra field operations. Additional

Biocompatibility of a new device of self-expandable covered and non-covered tracheal stent: comparative study in rats

Directory of Open Access Journals (Sweden)

Olavo Ribeiro Rodrigues

2013-01-01

Full Text Available PURPOSE: To investigate the compatibility of a new model of self-expandable tracheal stent in rats. METHODS: A new device of polyurethane covered and non - covered stent was placed in the trachea of Wistar rats. Animals were distributed in two groups: the polyurethane covered and non-covered group. Macroscopic parameters included position within the tracheal lumen, adherence to the mucosa, degree of dilatation, permeability and internal diameter. Microscopic findings evaluated were: incorporation, inflammatory activity, granulation tissue and epithelial revetment injuries. The observation follow-up was six weeks. All parameters were quantified based on determined score values. Incorporation of the stents was evaluated based on the observation if the stent was fixed into the trachea or if it could be removed. Degree of dilatation was performed by external diameter measurements. Granulation tissue was evaluated by measurements of height of the tissue growing into the tracheal lumen. RESULTS: 100% of non-covered stents had total attachment to mucosa and 100% of polyurethane covered type had adherence only. Regarding dilatation, granulation tissue, inflammatory activity and internal diameter measurements, there were no significant differences between the groups. Pathological tracheal wall injuries were present in both groups. CONCLUSION: Both models of stent demonstrated biocompatibility with the trachea. Rats are suitable for an experimental model of tracheal stent study.

"Lolita": Genealogy of a Cover Girl

Science.gov (United States)

Savage, Shari L.

2015-01-01

At the publication of Vladimir Nabokov's controversial novel "Lolita" (1958), the author insisted that a girl never appear on the cover. This discourse analysis of 185 "Lolita" book covers, most of which feature a girl, considers the genealogy of "Lolita" in relation to representation, myth, and tacit knowledge…

(Clarias gariepinus Burchell, 1822) for

African Journals Online (AJOL)

Jane

2010-10-11

Oct 11, 2010 ... DMSO and glycerol provided hatching at least 50% of catfish eggs. ... However, sperm cryopreserved with glycerol had the lowest motility rate in the 2 trials (p < 0.05). The use ..... the top were screened from insect contamination of eggs by covering ..... Successful handstripping of hatchery breeding reared.

Percent Forest Cover (Future)

Data.gov (United States)

U.S. Environmental Protection Agency — Forests provide economic and ecological value. High percentages of forest cover (FORPCTFuture) generally indicate healthier ecosystems and cleaner surface water....

Covering Materials for Anaerobic Digesters Producing Biogas

International Nuclear Information System (INIS)

Itodo, I. N.; Philips, T. K.

2002-01-01

The suitability of foam, concrete and clay soil as covering material on anaerobic digesters producing biogas was investigated using four batch-type digesters of 20 litres volume. The methane yield from the digesters was of the order: foam >control> concrete > clay soil. The digester covered with foam had the highest methane yield, best temperature control and most favourable pH conditions. It is most suitable as cover material on anaerobic digesters

THz TDS of substance covered by disordered structure

Science.gov (United States)

Trofimov, V. A.; Zagursky, D. Y.; Zakharova, I. G.

2016-04-01

Computer simulation of a few-cycle pulse interaction with a substance covered by disordered structure is performed in order to study the effects imposed on spectra of transmitted and reflected pulses by presence of the cover. The substance is described by semi-classic approach and the cover is described by classic electrodynamics equations for linear isotropic medium. The cover consists of a number of layers with different properties which is considered to be the cause of the distortions. The influence of relation between pulse wavelength and cover layer thickness is illustrated. Computer simulation results are compared with those of physical experiments conducted for paper and other common materials.

19 CFR 212.03 - Proceedings covered.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Proceedings covered. 212.03 Section 212.03 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE IMPLEMENTATION OF THE EQUAL ACCESS TO JUSTICE ACT General Provisions § 212.03 Proceedings covered. (a) The Act...

A refratariedade das aves ao "Trypanosoma (Schizotrypanum cruzi" II - refratariedade das galinhas desde o nascimento; persistência da refratariedade após Bursectomia; infecções em ovos embrionados The refractory state of birds toward the Trypanosoma (Schizotrypanum cruzi: II - the refractory state begins at hatching and persists after bursectomy, Infections of embryonnated eggs

Directory of Open Access Journals (Sweden)

F. Nery-Guimarães

1972-01-01

Full Text Available "A refratariedade das galinhas ao T. (S. cruzi, ocorre desde o nascimento e não é eliminada pela bursectomia hormonal. Noventa e oito pintos de 1 a 15 dias de vida (normais ou tratados com testosterona inoculados com o T. (S. cruzi foram negativos. Deste modo, dificilmente a refratariedade poderia ser interpretada como decorrência de um "anticorpo natural", uma vez que a bursectomia provoca uma queda na produção de anticorpos e das gamaglobulinas. Em cerca de 50% de ovos embrionados (normais ou tratados com o hormônio foram vistos flagelados do 4º ao 12º dia de inoculação, observando-se ninhos de amastigotos em alguns embriões. Os pintos nascidos dos mesmos grupos dos ovos examinados e positivos, foram sistematicamente negativos pelo exame do sangue. Um deles sacrificado horas depois de nascido, mostrou amastigotos no coração, mas esses parasitos pareciam degenerados. Provavelmente, se alguns chegam a evoluir para tripomastigotos, estes são destruídos á medida que as células hospedeiras se rompem, e assim jamais são encontrados no sangue circulante.It has already been shown that the refractory state of chickens toward "T. (S. cruzi" appears early at time of hatch. Fifty-four normal newly hatched and inoculated chicks were negative. it has also been verified that this refractory state persists even after hormonal bursectomy (eggs being injected with 2.5 mg of testosterone. Forty-four bursectomized and inoculated newly hatched chicks were negative. If we consider the fact that bursectomy causes a deficiency in the production of antibodies and gammaglobulins, the refractory state seems not to occur on account of a "natural antibody". Inoculations of "T. (S. cruzi" made in 153 eggs (normal or treated with testosterone produced infections of variable intensity in about 50% of them. Although chicks newly hatched from the same groups were always negative. As we have some embryos to be positive until the 21st day of incubation it seems

In vitro effects of aqueous extract from Maytenus senegalensis (Lam.) Exell stem bark on egg hatching, larval migration and adult worms of Haemonchus contortus.

Science.gov (United States)

Zangueu, Calvin Bogning; Olounlade, Abiodoun Pascal; Ossokomack, Marlyse; Djouatsa, Yolande Noelle Nangue; Alowanou, Goue Géorcelin; Azebaze, Anatole Guy Blaise; Llorent-Martínez, Eulogio José; de Córdova, Maria Luisa Fernández; Dongmo, Alain Bertrand; Hounzangbe-Adote, Mawulé Sylvie

2018-05-02

Maytenus senegalensis is a common shrub which is scattered in tropical Africa. Different parts of this plant have been reported to be useful in traditional medicine against gastrointestinal disorders and intestinal worms. This study evaluated the anthelmintic activity of the aqueous stem bark extract of M. senegalensis using egg hatch assay (EHA), larval migration inhibition assay (LMIA) and adult worms' motility inhibition assay (AMIA). On EHA, the extract concentrations tested resulted in a significant (p  50%). These in vitro results suggest the presence of some anthelmintic properties in M. senegalensis extract, which is traditionally used by small farmers in west and central Africa. These effects may be due to the flavonoids and proanthocyanidins present in the extract and need to be studied under in vivo conditions.

GLCF: Landsat GeoCover

Science.gov (United States)

satellite imagery provided in a standardized, orthorectified format, covering the entire land surface of the * Orthorectification * Distribution Status * Hard Media Orders * Letters Delivered Quick Links * Create True Color

Multidimensional simulation of radon diffusion through earthen covers

International Nuclear Information System (INIS)

Mayer, D.W.; Gee, G.W.

1983-01-01

The purpose of this report is to document applications of the RADMD model used at PNL to perform analyses of radon diffusion through uranium mill tailings cover systems. The accuracy of the numerical formulation of the RADMD model was demonstrated through a comparison with a two-dimensional analytic solution to the radon diffusion equation. Excellent agreement was obtained between two-dimensional radon concentration profiles predicted by RADMD and those obtained with the analytic solution. A simulation was made of radon diffusion into a test canister using the two dimensional capabilities of RADMD. The radon flux profile was computed and illustrates the effects of the canister on the surface radon flux. The influence of the canister on the radon flux was shown to be significant under certain circumstances. Defects in earthen cover systems were evaluated using the three dimensional capabilities of RADMD. The results support the expectation that defective covers can increase the surface flux from a covered talings pile. Compared to a cover with no defects, radon flux could be elevated by as much as a factor of three when 20% of the radon control layer area contained pockets of reduced moisture. The effects of temporal and spatial variations in moisture content have been modeled by coupling RADMD with a variable saturated flow model. Two dimensional simulations were made of the time dependence of radon flux from a tailings site before and after cover placement. The results demonstrated the expected flux reduction produced by a thick earthen cover. Time dependence of the radon flux after cover placement was attributed to slight changes in moisture content of the cover material with time. The particular cover studied had a compacted clay layer that effectively attenuated the radon

77 FR 5317 - Medicaid Program; Covered Outpatient Drugs

Science.gov (United States)

2012-02-02

... for Medicare & Medicaid Services 42 CFR Part 447 Medicaid Program; Covered Outpatient Drugs; Proposed... Part 447 [CMS-2345-P] RIN 0938-AQ41 Medicaid Program; Covered Outpatient Drugs AGENCY: Centers for... requirements pertaining to Medicaid reimbursement for covered outpatient drugs to implement provisions of the...

Winter cover crop effect on corn seedling pathogens

Science.gov (United States)

Cover crops are an excellent management tool to improve the sustainability of agriculture. Winter rye cover crops have been used successfully in Iowa corn-soybean rotations. Unfortunately, winter rye cover crops occasionally reduce yields of the following corn crop. We hypothesize that one potential...

Smart cover glass for automotive applications

Science.gov (United States)

Chung, Sang Kug

2017-11-01

This paper presents a smart cover glass based on electrowetting-on-dielectric (EWOD) actuation for automotive applications. It can remove water droplets in a wide range of sizes to allow the camera's lens to get clean at any time. The proposed cover glass offers a simple design structure to be easily installed on any device but provides a fast and energy efficient droplet cleaning operation. As proof of concept, a real imaging test is carried out using a mobile smartphone camera and landscape photography. When water droplets with different volumes are on the camera cover glass, the image of landscape photography is distorted with blurred spots. However, the distorted image is restored by removing the droplets through EWOD actuation.

ISLSCP II Historical Croplands Cover, 1700-1992

Data.gov (United States)

National Aeronautics and Space Administration — The Historical Croplands Cover data set was developed to understand the consequences of historical changes in land use and land cover for ecosystem goods and...

Watershed impervious cover relative to stream location

Data.gov (United States)

U.S. Environmental Protection Agency — Estimates of watershed (12-digit huc) impervious cover and impervious cover near streams and water body shorelines for three dates (2001, 2006, 2011) using NLCD...

ISLSCP II Historical Croplands Cover, 1700-1992

Data.gov (United States)

National Aeronautics and Space Administration — ABSTRACT: The Historical Croplands Cover data set was developed to understand the consequences of historical changes in land use and land cover for ecosystem goods...

Engineered soil covers for management of salt impacted sites

International Nuclear Information System (INIS)

Sweeney, D.A.; Tratch, D.J.

2005-01-01

The use of engineered soil cover systems to mitigate environmental impacts from tailings and waste rock piles is becoming an accepted practice. This paper presented design concepts for soil covers related to reclamation practices in the mining industry as an effective risk management practice at salt impacted sites. Research and field programs have demonstrated that a layered engineered soil cover can reduce or eliminate infiltration. Key components of the system included re-establishing surface vegetation to balance precipitation fluxes with evapotranspiration potential, and design of a capillary break below the rooting zone to minimize deeper seated infiltration. It was anticipated that the incorporation of a vegetation cover and a capillary break would minimize infiltration into the waste rock or tailing pile and reduce the generation of acid rock drainage (ARD). Design of a layered soil cover requires the incorporation of meteorological data, moisture retention characteristics of the impacted soils, and proposed engineered cover materials. Performance of the soil cover was predicted using a finite element model combined with meteorological data from the site area, unsaturated soil properties of the parent sub-surface soils and potential covered materials. The soil cover design consisted of re-vegetation and a loose clay cover overlying a compacted till layer. The design was conducted for an off site release of salt impacted pasture land adjacent to a former highway maintenance yard. The model predicted minimal infiltration during high precipitation events and no infiltration during low precipitation events. Results indicated that the proposed soil cover would enable re-establishment of a productive agricultural ground cover, as well as minimizing the potential for additional salt migration. It was concluded that further research and development is needed to ensure that the cover system is an acceptable method for long-term risk management. 17 refs., 5 figs

GAP Land Cover - Image

Data.gov (United States)

Minnesota Department of Natural Resources — This raster dataset is a simple image of the original detailed (1-acre minimum), hierarchically organized vegetation cover map produced by computer classification of...

GAP Land Cover - Vector

Data.gov (United States)

Minnesota Department of Natural Resources — This vector dataset is a detailed (1-acre minimum), hierarchically organized vegetation cover map produced by computer classification of combined two-season pairs of...

Percent of Impervious Cover

Data.gov (United States)

U.S. Environmental Protection Agency — High amounts of impervious cover (parking lots, rooftops, roads, etc.) can increase water runoff, which may directly enter surface water. Runoff from roads often...

Clouds cover variability in São Paulo

Directory of Open Access Journals (Sweden)

Luciana Machado de Moura

2016-11-01

Full Text Available Clouds cover observations are performed by visual inspection which determines the fraction of the sky that is overcast. However, visual observation of clouds cover is a very subjective method, and can vary significantly among observers. This study examined the variability in clouds cover over the city of São Paulo between 1961 and 2013, using clouds cover fraction data observed at the weather station operated by IAG / USP. The study also used two techniques based on visible radiance data observed by the GOES-10 satellite in order to indirectly estimate clouds cover. In order to ensure consistency, the estimated and observed cloudiness was compared with the clearness index, which is the ratio between the total solar radiation observed at the weather station and the incoming solar irradiation at the top of atmosphere. The study found consistency between the various databases that showed similar behavior in all of the seasons of the year. The largest cloudiness values occurred in the summer and lowest in the winter.

Performance of japanese quail chickens injected with monosodium glutamate in the early post hatch period

International Nuclear Information System (INIS)

Fahmy, M.O.; Ezzat, I.E. and others

2002-01-01

Neo hatched Japanese quails chicks were divided equally into three groups (G1, G2 and G3) and injected once subcutaneously with monosodium glutamate (MSG) at 0,2 or 4 mg/g body weight for G1, G2 and G3 respectively. The obtained results clear that, 1-At-marketing stage, body weight increased by about 4% and 6%, feed conversion ratio reduced by 8.7% and 5.7% in-groups G2 and G3 respectively. 2-MSG had no significant effect on male and female serum T4 as well as male serum T3. The injection with 2-mg MSG per gram body weight increased female serum T3 significantly. 3-MSG increased significantly fat % DM in the male and female quails. This treatment in was positively correlated with the amount of injected MSG. Ash % DM and protein % DM were decreased significantly in both injected males and females and the reduction was dose dependent. 5-in males, weights of heart, spleen and testes besides weights and lengths of gastrointestinal tract regions were not significantly affected by MSG administration. 6-in females, the injection with MSG (2 mg/g body weight) significantly reduced the weight as percent body weight, moreover, the administration of MSG had no significant effect on the weights or the lengths of the remain parameters of the females gastrointestinal tract regions, ovary, oviduct, heart and spleen

39 CFR 233.3 - Mail covers.

Science.gov (United States)

2010-07-01

.... For purpose of these regulations, the following terms are hereby defined. (1) Mail cover is the... criminal law. (3) When time is of the essence, the Chief Postal Inspector, or designee, may act upon an... furnish information as defined in § 233.3(c)(1) to any person, except as authorized by a mail cover order...

Percent Wetland Cover (Future)

Data.gov (United States)

U.S. Environmental Protection Agency — Wetlands act as filters, removing or diminishing the amount of pollutants that enter surface water. Higher values for percent of wetland cover (WETLNDSPCT) may be...

[Cover motifs of the Tidsskrift. A 14-year cavalcade].

Science.gov (United States)

Nylenna, M

1998-12-10

In 1985 the Journal of the Norwegian Medical Association changed its cover policy, moving the table of contents inside the Journal and introducing cover illustrations. This article provides an analysis of all cover illustrations published over this 14-year period, 420 covers in all. There is a great variation in cover motifs and designs and a development towards more general motifs. The initial emphasis on historical and medical aspects is now less pronounced, while the use of works of art and nature motifs has increased, and the cover now more often has a direct bearing on the specific contents of the issue. Professor of medical history Oivind Larsen has photographed two thirds of the covers and contributed 95% of the inside essay-style reflections on the cover motif. Over the years, he has expanded the role of the historian of medicine disseminating knowledge to include that of the raconteur with a personal tone of voice. The Journal's covers are now one of its most characteristic features, emblematic of the Journal's ambition of standing for quality and timelessness vis-à-vis the news media, and of its aim of bridging the gap between medicine and the humanities.

Effect of litter, leaf cover and cover of basal internodes of the dominant species Molinia caerulea on seedling recruitment and established vegetation

Science.gov (United States)

Janeček, Štěpán; Lepš, Jan

2005-09-01

The effects of litter removal, leaf cover of established plants and cover of basal internodes of a dominant species Molinia caerulea on seedling germination and the dynamics of established plants were studied in a field experiment in an oligotrophic wet meadow. Although the negative influence of litter on total seedling number and seedling species composition was non-significant, litter significantly affected the dynamics of the established vegetation and caused inhibition of total leaf cover development. The effects of total leaf cover of established plants on seedling establishment changed during the vegetation season. Whereas the effect of total leaf cover was positive at the start and in the middle of the vegetation season, at the end the total leaf cover negatively affected seedling establishment. Both total leaf cover and cover of basal internodes affected seedling composition. Effects of these two variables were statistically separable suggesting that they are based on different mechanisms. The response of seedling establishment to these factors was species specific and, consequently, our data support the hypothesis that that biotically generated spatial heterogeneity can promote species co-existence through the differentiation of species regeneration niches.

21 CFR 1404.200 - What is a covered transaction?

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false What is a covered transaction? 1404.200 Section 1404.200 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Covered Transactions § 1404.200 What is a covered transaction? A covered transaction is a...

Preheating Water In The Covers Of Solar Water Heaters

Science.gov (United States)

Bhandari, Pradeep

1995-01-01

Solar water heaters that include glass covers over absorber plates redesigned to increase efficiencies according to proposal. Redesign includes modification of single-layer glass cover into double-layer glass cover and addition of plumbing so cool water to be heated made to flow between layers of cover before entering absorber plate.

Validation of Land Cover Products Using Reliability Evaluation Methods

Directory of Open Access Journals (Sweden)

Wenzhong Shi

2015-06-01

Full Text Available Validation of land cover products is a fundamental task prior to data applications. Current validation schemes and methods are, however, suited only for assessing classification accuracy and disregard the reliability of land cover products. The reliability evaluation of land cover products should be undertaken to provide reliable land cover information. In addition, the lack of high-quality reference data often constrains validation and affects the reliability results of land cover products. This study proposes a validation schema to evaluate the reliability of land cover products, including two methods, namely, result reliability evaluation and process reliability evaluation. Result reliability evaluation computes the reliability of land cover products using seven reliability indicators. Process reliability evaluation analyzes the reliability propagation in the data production process to obtain the reliability of land cover products. Fuzzy fault tree analysis is introduced and improved in the reliability analysis of a data production process. Research results show that the proposed reliability evaluation scheme is reasonable and can be applied to validate land cover products. Through the analysis of the seven indicators of result reliability evaluation, more information on land cover can be obtained for strategic decision-making and planning, compared with traditional accuracy assessment methods. Process reliability evaluation without the need for reference data can facilitate the validation and reflect the change trends of reliabilities to some extent.

No maternal or direct effects of ocean acidification on egg hatching in the Arctic copepod Calanus glacialis.

Science.gov (United States)

Thor, Peter; Vermandele, Fanny; Carignan, Marie-Helene; Jacque, Sarah; Calosi, Piero

2018-01-01

Widespread ocean acidification (OA) is transforming the chemistry of the global ocean and the Arctic is recognised as the region where this transformation will occur at the fastest rate. Moreover, many Arctic species are considered less capable of tolerating OA due to their lower capacity for acid-base regulation. This inability may put severe restraints on many fundamental functions, such as growth and reproductive investments, which ultimately may result in reduced fitness. However, maternal effects may alleviate severe effects on the offspring rendering them more tolerant to OA. In a highly replicated experiment we studied maternal and direct effects of OA predicted for the Arctic shelf seas on egg hatching time and success in the keystone copepod species Calanus glacialis. We incubated females at present day conditions (pHT 8.0) and year 2100 extreme conditions (pHT 7.5) during oogenesis and subsequently reciprocally transplanted laid eggs between these two conditions. Statistical tests showed no effects of maternal or direct exposure to OA at this level. We hypothesise that C. glacialis may be physiologically adapted to egg production at low pH since oogenesis can also take place at conditions of potentially low haemolymph pH of the mother during hibernation in the deep.

The First Zoeal Stages of Parapanope euagora and Halimede fragifer (Decapoda: Pilumnoidea: Galenidae Hatched in the Laboratory

Directory of Open Access Journals (Sweden)

Lee, Seok Hyun

2016-04-01

Full Text Available The first zoeas of Parapanope euagora and Halimede fragifer hatched in the laboratory from two ovigerous galenid crabs of Pilumnoidea were collected from Jindo Island, Jeolanam-do, southern Korea. Their morphologies are described in P. euagora for the first time in the world and re-described in H. fragifer with the color images of live zoeas. In this study, they show a general morphology of Pilumnoidea by having a long antennal exopod, an endopod of the maxillule with 1, 2+4 setae, an endopod of the maxilla with 3+5 setae, and a fork of the telson with two lateral armatures. However, the first zoea of P. euagora differs from other known zoeas of pilumnoid species including H. fragifer by having a long antennal exopod with a medial seta and spine, not two spines, and a fork of telson with two lateral setae, not a seta and spine. Such characteristics of the antennal exopod and the fork of telson are reported for the first time in the pilumnoid zoeas. A comparison between the first zoeal stage of H. fragifer in this study and that of Terada shows minute differences in the characteristics of the antennule and the fork of telson.

Differences in breeding bird assemblages related to reed canary grass cover cover and forest structure on the Upper Mississippi River

Science.gov (United States)

Kirsch, Eileen M.; Gray, Brian R.

2017-01-01

Floodplain forest of the Upper Mississippi River provides habitat for an abundant and diverse breeding bird community. However, reed canary grass Phalaris arundinacea invasion is a serious threat to the future condition of this forest. Reed canary grass is a well-known aggressive invader of wetland systems in the northern tier states of the conterminous United States. Aided by altered flow regimes and nutrient inputs from agriculture, reed canary grass has formed dense stands in canopy gaps and forest edges, retarding tree regeneration. We sampled vegetation and breeding birds in Upper Mississippi River floodplain forest edge and interior areas to 1) measure reed canary grass cover and 2) evaluate whether the breeding bird assemblage responded to differences in reed canary grass cover. Reed canary grass was found far into forest interiors, and its cover was similar between interior and edge sites. Bird assemblages differed between areas with more or less reed canary grass cover (.53% cover breakpoint). Common yellowthroat Geothlypis trichas, black-capped chickadee Parus atricapillus, and rose-breasted grosbeak Pheucticus ludovicianus were more common and American redstart Setophaga ruticilla, great crested flycatcher Myiarchus crinitus, and Baltimore oriole Icterus galbula were less common in sites with more reed canary grass cover. Bird diversity and abundance were similar between sites with different reed canary grass cover. A stronger divergence in bird assemblages was associated with ground cover ,15%, resulting from prolonged spring flooding. These sites hosted more prothonotary warbler Protonotaria citrea, but they had reduced bird abundance and diversity compared to other sites. Our results indicate that frequently flooded sites may be important for prothonotary warblers and that bird assemblages shift in response to reed canary grass invasion.

Analysis of radon protection cover on uranium tailings pile

International Nuclear Information System (INIS)

Zhang Zhe

1993-01-01

The average radon emanation rate of the whole surface over one year was used for evaluating the radon release of uranium tailings pile. The effective of radon protection cover depends on the shape and property of the tailings pile, the properties of covering and the control of air vadose in the pile. It was indicated that the covering with low diffusion coefficient, small porosity and bad permeability was suitable to cover the pile. The analytical formula of the covering layer thickness was given

Development of a 30 m Spatial Resolution Land Cover of Canada: Contribution to the Harmonized North America Land Cover Dataset

Science.gov (United States)

Pouliot, D.; Latifovic, R.; Olthof, I.

2017-12-01

Land cover is needed for a large range of environmental applications regarding climate impacts and adaption, emergency response, wildlife habitat, air quality, water yield, etc. In Canada a 2008 user survey revealed that the most practical scale for provision of land cover data is 30 m, nationwide, with an update frequency of five years (Ball, 2008). In response to this need the Canada Centre for Remote Sensing has generated a 30 m land cover of Canada for the base year 2010 as part of a planned series of maps at the recommended five year update frequency. This land cover is the Canadian contribution to the North American Land Change Monitoring System initiative, which seeks to provide harmonized land cover across Canada, the United States, and Mexico. The methodology developed in this research utilized a combination of unsupervised and machine learning techniques to map land cover, blend results between mapping units, locally optimize results, and process some thematic attributes with specific features sets. Accuracy assessment with available field data shows it was on average 75% for the five study areas assessed. In this presentation an overview of the unique processing aspects, example results, and initial accuracy assessment will be discussed.

Monitoring Areal Snow Cover Using NASA Satellite Imagery

Science.gov (United States)

Harshburger, Brian J.; Blandford, Troy; Moore, Brandon

2011-01-01

The objective of this project is to develop products and tools to assist in the hydrologic modeling process, including tools to help prepare inputs for hydrologic models and improved methods for the visualization of streamflow forecasts. In addition, this project will facilitate the use of NASA satellite imagery (primarily snow cover imagery) by other federal and state agencies with operational streamflow forecasting responsibilities. A GIS software toolkit for monitoring areal snow cover extent and producing streamflow forecasts is being developed. This toolkit will be packaged as multiple extensions for ArcGIS 9.x and an opensource GIS software package. The toolkit will provide users with a means for ingesting NASA EOS satellite imagery (snow cover analysis), preparing hydrologic model inputs, and visualizing streamflow forecasts. Primary products include a software tool for predicting the presence of snow under clouds in satellite images; a software tool for producing gridded temperature and precipitation forecasts; and a suite of tools for visualizing hydrologic model forecasting results. The toolkit will be an expert system designed for operational users that need to generate accurate streamflow forecasts in a timely manner. The Remote Sensing of Snow Cover Toolbar will ingest snow cover imagery from multiple sources, including the MODIS Operational Snowcover Data and convert them to gridded datasets that can be readily used. Statistical techniques will then be applied to the gridded snow cover data to predict the presence of snow under cloud cover. The toolbar has the ability to ingest both binary and fractional snow cover data. Binary mapping techniques use a set of thresholds to determine whether a pixel contains snow or no snow. Fractional mapping techniques provide information regarding the percentage of each pixel that is covered with snow. After the imagery has been ingested, physiographic data is attached to each cell in the snow cover image. This data

South African National Land-Cover Change Map

African Journals Online (AJOL)

Fritz Schoeman

monitoring land-cover change at a national scale over time using EO data. 2. .... assist with final results reporting and analysis on a sub-national level. ..... South African Land-Cover Characteristics Database: A synopsis of the landscape.

Deriving Snow Cover Metrics for Alaska from MODIS

Directory of Open Access Journals (Sweden)

Chuck Lindsay

2015-09-01

Full Text Available Moderate Resolution Imaging Spectroradiometer (MODIS daily snow cover products provide an opportunity for determining snow onset and melt dates across broad geographic regions; however, cloud cover and polar darkness are limiting factors at higher latitudes. This study presents snow onset and melt dates for Alaska, portions of western Canada and the Russian Far East derived from Terra MODIS snow cover daily 500 m grid data (MOD10A1 and evaluates our method for filling data gaps caused by clouds or polar darkness. Pixels classified as cloud or no data were reclassified by: spatial filtering using neighboring pixel values; temporal filtering using pixel values for days before/after cloud cover; and snow-cycle filtering based on a time series assessment of a pixel’s position within snow accumulation, cover or melt periods. During the 2012 snow year, these gap-filling methods reduced cloud pixels from 27.7% to 3.1%. A total of 12 metrics (e.g., date of first and last snow, date of persistent snow cover and periods of intermittence for each pixel were calculated by snow year. A comparison of MODIS-derived snow onset and melt dates with in situ observations from 244 weather stations generally showed an early bias in MODIS-derived dates and an effect of increasing cloudiness exacerbating bias. Our results show that mean regional duration of seasonal snow cover is 179–311 days/year and that snow cover is often intermittent, with 41% of the area experiencing ≥2 snow-covered periods during a snow season. Other regional-scale patterns in the timing of snow onset and melt are evident in the yearly 500 m gridded products publically available at http://static.gina.alaska.edu/NPS_products/MODIS_snow/.

Enhanced Cover Assessment Project:Soil Manipulation and Revegetation Tests

Energy Technology Data Exchange (ETDEWEB)

Waugh, W. Joseph [Navarro Research and Engineering, Inc.; Albright, Dr. Bill [Desert Research Inst. (DRI), Reno, NV (United States); Benson, Dr. Craig [University of Wisconsin-Madison

2014-02-01

The U.S. Department of Energy Office of Legacy Management is evaluating methods to enhance natural changes that are essentially converting conventional disposal cell covers for uranium mill tailings into water balance covers. Conventional covers rely on a layer of compacted clayey soil to limit exhalation of radon gas and percolation of rainwater. Water balance covers rely on a less compacted soil “sponge” to store rainwater, and on soil evaporation and plant transpiration (evapotranspiration) to remove stored water and thereby limit percolation. Over time, natural soil-forming and ecological processes are changing conventional covers by increasing hydraulic conductivity, loosening compaction, and increasing evapotranspiration. The rock armor on conventional covers creates a favorable habitat for vegetation by slowing soil evaporation, increasing soil water storage, and trapping dust and organic matter, thereby providing the water and nutrients needed for plant germination, survival, and sustainable transpiration. Goals and Objectives Our overall goal is to determine if allowing or enhancing these natural changes could improve cover performance and reduce maintenance costs over the long term. This test pad study focuses on cover soil hydrology and ecology. Companion studies are evaluating effects of natural and enhanced changes in covers on radon attenuation, erosion, and biointrusion. We constructed a test cover at the Grand Junction disposal site to evaluate soil manipulation and revegetation methods. The engineering design, construction, and properties of the test cover match the upper three layers of the nearby disposal cell cover: a 1-foot armoring of rock riprap, a 6-inch bedding layer of coarse sand and gravel, and a 2-foot protection layer of compacted fine soil. The test cover does not have a radon barrier—cover enhancement tests leave the radon barrier intact. We tested furrowing and ripping as means for creating depressions parallel to the slope

Tree Cover Mapping Tool—Documentation and user manual

Science.gov (United States)

Cotillon, Suzanne E.; Mathis, Melissa L.

2016-06-02

The Tree Cover Mapping (TCM) tool was developed by scientists at the U.S. Geological Survey Earth Resources Observation and Science Center to allow a user to quickly map tree cover density over large areas using visual interpretation of high resolution imagery within a geographic information system interface. The TCM tool uses a systematic sample grid to produce maps of tree cover. The TCM tool allows the user to define sampling parameters to estimate tree cover within each sample unit. This mapping method generated the first on-farm tree cover maps of vast regions of Niger and Burkina Faso. The approach contributes to implementing integrated landscape management to scale up re-greening and restore degraded land in the drylands of Africa. The TCM tool is easy to operate, practical, and can be adapted to many other applications such as crop mapping, settlements mapping, or other features. This user manual provides step-by-step instructions for installing and using the tool, and creating tree cover maps. Familiarity with ArcMap tools and concepts is helpful for using the tool.

Statistical Monitoring of Changes to Land Cover

KAUST Repository

Zerrouki, Nabil; Harrou, Fouzi; Sun, Ying

2018-01-01

Accurate detection of changes in land cover leads to better understanding of the dynamics of landscapes. This letter reports the development of a reliable approach to detecting changes in land cover based on remote sensing and radiometric data

Mathematical Foundation for Plane Covering Using Hexagons

Science.gov (United States)

Johnson, Gordon G.

1999-01-01

This work is to indicate the development and mathematical underpinnings of the algorithms previously developed for covering the plane and the addressing of the elements of the covering. The algorithms are of interest in that they provides a simple systematic way of increasing or decreasing resolution, in the sense that if we have the covering in place and there is an image superimposed upon the covering, then we may view the image in a rough form or in a very detailed form with minimal effort. Such ability allows for quick searches of crude forms to determine a class in which to make a detailed search. In addition, the addressing algorithms provide an efficient way to process large data sets that have related subsets. The algorithms produced were based in part upon the work of D. Lucas "A Multiplication in N Space" which suggested a set of three vectors, any two of which would serve as a bases for the plane and also that the hexagon is the natural geometric object to be used in a covering with a suggested bases. The second portion is a refinement of the eyeball vision system, the globular viewer.

The Thermal Collector With Varied Glass Covers

International Nuclear Information System (INIS)

Luminosu, I.; Pop, N.

2010-01-01

The thermal collector with varied glass covers represents an innovation realized in order to build a collector able to reach the desired temperature by collecting the solar radiation from the smallest surface, with the highest efficiency. In the case of the thermal collector with variable cover glasses, the number of the glass plates covering the absorber increases together with the length of the circulation pipe for the working fluid. The thermal collector with varied glass covers compared to the conventional collector better meet user requirements because: for the same temperature increase, has the collecting area smaller; for the same collection area, realizes the highest temperature increase and has the highest efficiency. This works is addressed to researchers in the solar energy and to engineers responsible with air-conditioning systems design or industrial and agricultural products drying.

Vacuum-plasma coverings on the aircraft

International Nuclear Information System (INIS)

Shvetsov, V.D.; Teksin, Eh.K.; Lysyak, A.A.

1998-01-01

In the article are considered the perspectives of vacuum-plasma coverings using for engine components protection. The influence of operating factors on the durability of components which has the vacuum-plasma coverings is show.Leads in using the concept of informational parameter of quality.The recommendation about organization of engine with abolished components maintenance by methods of flyable conditions or reliability level are given

Analysis of BY-106 pump pit cover plate

International Nuclear Information System (INIS)

Coverdell, B.L.

1994-01-01

A new cover for the pump pit of Tank 241-BY-106 has been designed to allow the rotary core exhauster to be hooked up without requiring pit entry, riser modification, or equipment removal. The new pit cover is necessary to allow installation of two risers for reducing exposure, contamination, and waste. Computer analysis indicates that the safety margin of the pit cover plate with two risers is adequate. The computer stress model and input files are attached. The pit cover plate is a replacement for an existing plate; therefore seismic and wind loads were considered for the plate only

Eggs hatching and oncomiracidia lifespan of Dawestrema cycloancistrium, a monogenean parasitic on Arapaima gigas.

Science.gov (United States)

Maciel, Patricia Oliveira; Muniz, Celli Rodrigues; Alves, Rosiana Rodrigues

2017-11-30

Within the production chain of the Arapaima gigas (pirarucu), sanitary issues are still faced at the fingerling phase regarding infestations by the monogenean Dawestrema cycloancistrium. The present study had the objectives of describing the morphology and development phases of this parasite's eggs and oncomiracidia and determining the hatching time and lifespan of the oncomiracidia at different temperatures. D. cycloancistrium eggs were oval and elongated and had a single long appendage at one pole. The egg development was divided into four phases: embryonated egg, developing egg, larva appearance and ecloded egg. They were found in four forms: isolated in gill filaments; grouped in clusters that were anchored in a gill filament; grouped in clusters and entangled in part of a dead adult monogenean; and grouped in clusters in the environment, fixed to a substrate. Eclosion occurred after 72-96h, with faster development at 29°C and 32°C than at 24°C. The morphology of the oncomiracidia were rounded and elongated. They had two pairs of pigmented eye-spots as well as two ciliated areas located on each lateral part of the body and another on the anterior part of the body. The lifespan of the D. cycloancistrium oncomiracidia were 50 and 58h at 24°C and 27°C, respectively. Larvae were found in the mucus, indicating that the oncomiracidia penetrated the host integument. Understanding reproductive aspects of the D. cycloancistrium monogenean is important for developing specific prophylactic management strategies in aquaculture and providing valuable data for further studies. Copyright © 2017 Elsevier B.V. All rights reserved.

EnviroAtlas - Land Cover for the Conterminous United States

Data.gov (United States)

U.S. Environmental Protection Agency — This dataset represents the percentage of land area that is classified as forest land cover, modified forest land cover, and natural land cover using the 2006...

Covered stent placement for the treatment of malignant superior vena cava syndrome: Is unilateral covered stenting and effective?

International Nuclear Information System (INIS)

Cho, Young Hoon; Gwon, Dong Il; Ko, Gi Young; Ko, Heung Kyu; Kim, Jin Hyoung; Shin, Ji Hoon; Yoon, Hyun Ki; Sung, Kyu Bo

2014-01-01

To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome. Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins. Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively. Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.

Covered stent placement for the treatment of malignant superior vena cava syndrome: Is unilateral covered stenting and effective?

Energy Technology Data Exchange (ETDEWEB)

Cho, Young Hoon; Gwon, Dong Il; Ko, Gi Young; Ko, Heung Kyu; Kim, Jin Hyoung; Shin, Ji Hoon; Yoon, Hyun Ki; Sung, Kyu Bo [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

2014-02-15

To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome. Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins. Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively. Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.

Final covering of the Ronneburg uranium mining site

International Nuclear Information System (INIS)

Hoepfner, Uwe

2007-01-01

The rehabilitation of WISMUT's former Ronneburg uranium mining site involves backfilling of waste rock to the Lichtenberg open pit. The relocation project comprises about 110 million m 3 of sulphide-bearing and AMD-generating waste rock which makes it the most important and most cost-intensive single surface restoration project conducted by WISMUT at the Ronneburg site. The backfilled waste rock has to be covered on an area of about 220 ha to control water infiltration and gas diffusion. Design planning for the final cover placement which began in 2004 had to be based on a comprehensive cost-benefit analysis as well on field tests of alternative cover options which are in compliance with legal requirements. An intensive testing program concerning the vadose zone of soil covers has therefore been started in 2000. The paper presents an overview of the monitoring program and the results of the vadose zone measurements. The water of soil covers have to be predicted for extended evaluation periods. Therefore water balance simulations of single layer covers (storage and evaporation concept) taking current and future soil and climate conditions into account are performed with the HYDRUS 2D code. (author)

Application of the FluEgg model to predict transport of Asian carp eggs in the Saint Joseph River (Great Lakes tributary)

Science.gov (United States)

Garcia, Tatiana; Murphy, Elizabeth A.; Jackson, P. Ryan; Garcia, Marcelo H.

2015-01-01

The Fluvial Egg Drift Simulator (FluEgg) is a three-dimensional Lagrangian model that simulates the movement and development of Asian carp eggs until hatching based on the physical characteristics of the flow field and the physical and biological characteristics of the eggs. This tool provides information concerning egg development and spawning habitat suitability including: egg plume location, egg vertical and travel time distribution, and egg-hatching risk. A case study of the simulation of Asian carp eggs in the Lower Saint Joseph River, a tributary of Lake Michigan, is presented. The river hydrodynamic input for FluEgg was generated in two ways — using hydroacoustic data and using HEC-RAS model data. The HEC-RAS model hydrodynamic input data were used to simulate 52 scenarios covering a broad range of flows and water temperatures with the eggs at risk of hatching ranging from 0 to 93% depending on river conditions. FluEgg simulations depict the highest percentage of eggs at risk of hatching occurs at the lowest discharge and at peak water temperatures. Analysis of these scenarios illustrates how the interactive relation among river length, hydrodynamics, and water temperature influence egg transport and hatching risk. An improved version of FluEgg, which more realistically simulates dispersion and egg development, is presented. Also presented is a graphical user interface that facilitates the use of FluEgg and provides a set of post-processing analysis tools to support management decision-making regarding the prevention and control of Asian carp reproduction in rivers with or without Asian carp populations.

[Breeding biology of the whiskered auklet (Aethia pygmaea): incubation, chick growth, and feather ontogenesis].

Science.gov (United States)

Koniukhov, N B; Zubakin, V A; Williams, J; Fischer, J

2000-01-01

This is the second publication on the results of studies of the whiskered auklet breeding biology on Buldir Island. In 1993, according to the time of chick hatching the egg-laying period began in late April-early May. The single egg was incubated by both parents, which relieved each other once a day, usually at early night. Among the chicks under observation, the first hatched on June 11; the median of hatching was on June 17. After hatching, the egg shell usually remained in the nest. The chick was continuously brooded by one of parents for the first several days but since the age of 7-9 days, it stayed in the nest by itself during the daytime. Each parent fed the chick once a day, at early night, although occasional feedings were recorded also during daytime and at dawn. A newly hatched chick was covered by typical embryonal (natal) down. The remiges, rectrices, their coverts, and large feathers on pteryla humeralis had a mesoptile stage during their growth (the second down generation). The juvenile plumage consisted of semiplumes of types I and II and contour feathers of type I and, possibly, type II. In fledglings, the ornamental feathers were underdeveloped: the crest was absent and facial plumes only began growing. By reaching 100 g, the chicks left their nests at the age of about 37 days. A longer nesting period than in other Aethia auklets appears to be related to a low feeding rate due to the nocturnal activity in the colony.

Experimental study and simulations of infiltration in evapotranspiration landfill covers

Directory of Open Access Journals (Sweden)

Wen-xian Zhang

2009-09-01

Full Text Available Various cover systems have been designed for landfill sites in order to minimize infiltration (percolation into the underlying waste. This study evaluated the soil water balance performance of evapotranspiration covers (ET covers and simulated percolation in the systems using the active region model (ARM. Experiments were conducted to measure water flow processes and water balance components in a bare soil cover and different ET covers. Results showed that vegetation played a critical role in controlling the water balance of the ET covers. In soil profiles of 60-cm depth with and without vegetation cover, the maximum soil water storage capacities were 97.2 mm and 62.8 mm, respectively. The percolation amount in the bare soil was 2.1 times that in the vegetation-covered soil. The ARM simulated percolation more accurately than the continuum model because it considered preferential flow. Numerical simulation results also indicated that using the ET cover system was an effective way of removing water through evapotranspiration, thus reducing percolation.

Chemical composition and efficacy in the egg-hatching inhibition of essential oil of Piper aduncum against Haemonchus contortus from sheep

Directory of Open Access Journals (Sweden)

Gisele Lopes Oliveira

Full Text Available Piper aduncum L., Piperaceae, has been used to treat mainly inflammatory diseases and has shown several biological activities such as insecticidal and larvicidal. The aim of this study was to analyze the chemical composition of essential oil of P. aduncum and its efficacy to egg-hatching inhibition of Haemonchus contortus from sheep. The essential oil was obtained from leaves and analysed by gas chromatography coupled to flame ionization detector and gas chromatography coupled to mass spectrometry. It was possible to characterize 22 different substances, among them monoterpenes (80.6% and sesquiterpenes (13.9%. The major compound was identified as 1,8-cineole (55.8%. Eggs of the nematode were exposed to four concentrations of the essential oil. Levamisole phosphate was used as positive control. The essential oil showed to be effective in inhibiting H. contortus hatchability and the LC90 was calculated as 8.9 mg.ml-1. These results can point out the P. aduncumessential oil and its chemical components as potential alternative to control of H. contortus

Numerical studies of large penetrations and closures for containment vessels subjected to loadings beyond the design basis

International Nuclear Information System (INIS)

Kulak, R.F.; Hsieh, B.J.; Kennedy, J.M.; Ash, J.E.; McLennan, G.A.

1984-01-01

Numerical simulations of the macro-deformations of the sealing surfaces (gasketed junctures) of a PWR steel containment vessel's equipment hatch and a BWR Mk II containment vessel head have been performed. Results for the equipment hatch juncture indicate that the rotations of the hatch cover and penetration sleeve must be accounted for when performing leakage analysis because they can effect the compression of the gasket even though the gasket is in a pressure-seated configuration. Results from a leakage analysis indicated that excessive leakage can occur if the surface roughness is high and/or the compression set is high. Results for the Mk II head show that both the temperature and pressure loadings must be taken into account to obtain realistic responses. The temperature difference between the flanges and bolts has the important net effect of keeping the gasketed juncture closed, that is in metal-to-metal contact. Due to the high accident temperature, the gasket itself was found to achieve 100% compression set and thus could not perform its sealing function within the juncture

Non-commutative covering spaces and their symmetries

DEFF Research Database (Denmark)

Canlubo, Clarisson

dened and its corresponding Galois theory. Using this and basic concepts from algebraic geometryand spectral theory, we will give a full description of the general structure of non-centralcoverings. Examples of coverings of the rational and irrational non-commutative tori will alsobe studied. Using...... will explain this and relate it to bi-Galois theory.Using the OZ-transform, we will show that non-commutative covering spaces come in pairs.Several categories of covering spaces will be dened and studied. Appealing to Tannaka duality,we will explain how this lead to a notion of an etale fundamental group...

Determinants of woody cover in African savannas

Science.gov (United States)

Sankaran, M.; Hanan, N.P.; Scholes, Robert J.; Ratnam, J.; Augustine, D.J.; Cade, B.S.; Gignoux, J.; Higgins, S.I.; Le, Roux X.; Ludwig, F.; Ardo, J.; Banyikwa, F.; Bronn, A.; Bucini, G.; Caylor, K.K.; Coughenour, M.B.; Diouf, A.; Ekaya, W.; Feral, C.J.; February, E.C.; Frost, P.G.H.; Hiernaux, P.; Hrabar, H.; Metzger, K.L.; Prins, H.H.T.; Ringrose, S.; Sea, W.; Tews, J.; Worden, J.; Zambatis, N.

2005-01-01

Savannas are globally important ecosystems of great significance to human economies. In these biomes, which are characterized by the co-dominance of trees and grasses, woody cover is a chief determinant of ecosystem properties 1-3. The availability of resources (water, nutrients) and disturbance regimes (fire, herbivory) are thought to be important in regulating woody cover1,2,4,5, but perceptions differ on which of these are the primary drivers of savanna structure. Here we show, using data from 854 sites across Africa, that maximum woody cover in savannas receiving a mean annual precipitation (MAP) of less than ???650 mm is constrained by, and increases linearly with, MAP. These arid and semi-arid savannas may be considered 'stable' systems in which water constrains woody cover and permits grasses to coexist, while fire, herbivory and soil properties interact to reduce woody cover below the MAP-controlled upper bound. Above a MAP of ???650 mm, savannas are 'unstable' systems in which MAP is sufficient for woody canopy closure, and disturbances (fire, herbivory) are required for the coexistence of trees and grass. These results provide insights into the nature of African savannas and suggest that future changes in precipitation 6 may considerably affect their distribution and dynamics. ?? 2005 Nature Publishing Group.

COVERS Neonatal Pain Scale: Development and Validation

Directory of Open Access Journals (Sweden)

Ivan L. Hand

2010-01-01

Full Text Available Newborns and infants are often exposed to painful procedures during hospitalization. Several different scales have been validated to assess pain in specific populations of pediatric patients, but no single scale can easily and accurately assess pain in all newborns and infants regardless of gestational age and disease state. A new pain scale was developed, the COVERS scale, which incorporates 6 physiological and behavioral measures for scoring. Newborns admitted to the Neonatal Intensive Care Unit or Well Baby Nursery were evaluated for pain/discomfort during two procedures, a heel prick and a diaper change. Pain was assessed using indicators from three previously established scales (CRIES, the Premature Infant Pain Profile, and the Neonatal Infant Pain Scale, as well as the COVERS Scale, depending upon gestational age. Premature infant testing resulted in similar pain assessments using the COVERS and PIPP scales with an r=0.84. For the full-term infants, the COVERS scale and NIPS scale resulted in similar pain assessments with an r=0.95. The COVERS scale is a valid pain scale that can be used in the clinical setting to assess pain in newborns and infants and is universally applicable to all neonates, regardless of their age or physiological state.

Land cover mapping of Greater Mesoamerica using MODIS data

Science.gov (United States)

Giri, Chandra; Jenkins, Clinton N.

2005-01-01

A new land cover database of Greater Mesoamerica has been prepared using moderate resolution imaging spectroradiometer (MODIS, 500 m resolution) satellite data. Daily surface reflectance MODIS data and a suite of ancillary data were used in preparing the database by employing a decision tree classification approach. The new land cover data are an improvement over traditional advanced very high resolution radiometer (AVHRR) based land cover data in terms of both spatial and thematic details. The dominant land cover type in Greater Mesoamerica is forest (39%), followed by shrubland (30%) and cropland (22%). Country analysis shows forest as the dominant land cover type in Belize (62%), Cost Rica (52%), Guatemala (53%), Honduras (56%), Nicaragua (53%), and Panama (48%), cropland as the dominant land cover type in El Salvador (60.5%), and shrubland as the dominant land cover type in Mexico (37%). A three-step approach was used to assess the quality of the classified land cover data: (i) qualitative assessment provided good insight in identifying and correcting gross errors; (ii) correlation analysis of MODIS- and Landsat-derived land cover data revealed strong positive association for forest (r2 = 0.88), shrubland (r2 = 0.75), and cropland (r2 = 0.97) but weak positive association for grassland (r2 = 0.26); and (iii) an error matrix generated using unseen training data provided an overall accuracy of 77.3% with a Kappa coefficient of 0.73608. Overall, MODIS 500 m data and the methodology used were found to be quite useful for broad-scale land cover mapping of Greater Mesoamerica.

Statistical Monitoring of Changes to Land Cover

KAUST Repository

Zerrouki, Nabil

2018-04-06

Accurate detection of changes in land cover leads to better understanding of the dynamics of landscapes. This letter reports the development of a reliable approach to detecting changes in land cover based on remote sensing and radiometric data. This approach integrates the multivariate exponentially weighted moving average (MEWMA) chart with support vector machines (SVMs) for accurate and reliable detection of changes to land cover. Here, we utilize the MEWMA scheme to identify features corresponding to changed regions. Unfortunately, MEWMA schemes cannot discriminate between real changes and false changes. If a change is detected by the MEWMA algorithm, then we execute the SVM algorithm that is based on features corresponding to detected pixels to identify the type of change. We assess the effectiveness of this approach by using the remote-sensing change detection database and the SZTAKI AirChange benchmark data set. Our results show the capacity of our approach to detect changes to land cover.

Fluorescence imaging to quantify crop residue cover

Science.gov (United States)

Daughtry, C. S. T.; Mcmurtrey, J. E., III; Chappelle, E. W.

1994-01-01

Crop residues, the portion of the crop left in the field after harvest, can be an important management factor in controlling soil erosion. Methods to quantify residue cover are needed that are rapid, accurate, and objective. Scenes with known amounts of crop residue were illuminated with long wave ultraviolet (UV) radiation and fluorescence images were recorded with an intensified video camera fitted with a 453 to 488 nm band pass filter. A light colored soil and a dark colored soil were used as background for the weathered soybean stems. Residue cover was determined by counting the proportion of the pixels in the image with fluorescence values greater than a threshold. Soil pixels had the lowest gray levels in the images. The values of the soybean residue pixels spanned nearly the full range of the 8-bit video data. Classification accuracies typically were within 3(absolute units) of measured cover values. Video imaging can provide an intuitive understanding of the fraction of the soil covered by residue.

Tree and impervious cover change in U.S

Science.gov (United States)

David J. Nowak; Eric J. Greenfield

2012-01-01

Paired aerial photographs were interpreted to assess recent changes in tree, impervious and other cover types in 20 U.S. cities as well as urban land within the conterminous United States. National results indicate that tree cover in urban areas of the United States is on the decline at a rate of about 7900 ha/yr or 4.0 million trees per year. Tree cover in 17 of the...

41 CFR 301-11.638 - May we offer a lump sum payment to cover the income tax liability on the covered ITRA?

Science.gov (United States)

2010-07-01

... payment to cover the income tax liability on the covered ITRA? 301-11.638 Section 301-11.638 Public... Thereafter Agency Responsibilities § 301-11.638 May we offer a lump sum payment to cover the income tax... understands that he/she is responsible for any income taxes without further reimbursement. See the...

41 CFR 301-11.538 - May we offer a lump sum payment to cover the income tax liability on the covered ITRA?

Science.gov (United States)

2010-07-01

... payment to cover the income tax liability on the covered ITRA? 301-11.538 Section 301-11.538 Public... 1994 Agency Responsibilities § 301-11.538 May we offer a lump sum payment to cover the income tax... understands that he/she is responsible for any income taxes without further reimbursement. (See the...

First evidence of dinosaurian secondary cartilage in the post-hatching skull of Hypacrosaurus stebingeri (Dinosauria, Ornithischia.

Directory of Open Access Journals (Sweden)

Alida M Bailleul

Full Text Available Bone and calcified cartilage can be fossilized and preserved for hundreds of millions of years. While primary cartilage is fairly well studied in extant and fossilized organisms, nothing is known about secondary cartilage in fossils. In extant birds, secondary cartilage arises after bone formation during embryonic life at articulations, sutures and muscular attachments in order to accommodate mechanical stress. Considering the phylogenetic inclusion of birds within the Dinosauria, we hypothesized a dinosaurian origin for this "avian" tissue. Therefore, histological thin sectioning was used to investigate secondary chondrogenesis in disarticulated craniofacial elements of several post-hatching specimens of the non-avian dinosaur Hypacrosaurus stebingeri (Ornithischia, Lambeosaurinae. Secondary cartilage was found on three membrane bones directly involved with masticatory function: (1 as nodules on the dorso-caudal face of a surangular; and (2 on the bucco-caudal face of a maxilla; and (3 between teeth as islets in the alveolar processes of a dentary. Secondary chondrogenesis at these sites is consistent with the locations of secondary cartilage in extant birds and with the induction of the cartilage by different mechanical factors - stress generated by the articulation of the quadrate, stress of a ligamentous or muscular insertion, and stress of tooth formation. Thus, our study reveals the first evidence of "avian" secondary cartilage in a non-avian dinosaur. It pushes the origin of this "avian" tissue deep into dinosaurian ancestry, suggesting the creation of the more appropriate term "dinosaurian" secondary cartilage.

Millennium Ecosystem Assessment: MA Rapid Land Cover Change

Data.gov (United States)

National Aeronautics and Space Administration — The Millennium Ecosystem Assessment: MA Rapid Land Cover Change provides data and information on global and regional land cover change in raster format for...

Covering radii are not matroid invariants

DEFF Research Database (Denmark)

Britz, Thomas Johann; Rutherford, Carrie G.

2005-01-01

We show by example that the covering radius of a binary linear code is not generally determined by the Tutte polynomial of the matroid. This answers Problem 361 (P.J. Cameron (Ed.), Research problems, Discrete Math. 231 (2001) 469–478).......We show by example that the covering radius of a binary linear code is not generally determined by the Tutte polynomial of the matroid. This answers Problem 361 (P.J. Cameron (Ed.), Research problems, Discrete Math. 231 (2001) 469–478)....

Winter rye cover crop effect on corn seedling pathogens

Science.gov (United States)

Cover crops have been grown successfully in Iowa, but sometimes a cereal rye cover crop preceding corn can reduce corn yields. Our research examines the effect of a rye cover crop on infections of the succeeding corn crop by soil fungal pathogens. Plant measurements included: growth stage, height, r...

16 CFR 501.5 - Paper table covers, bedsheets, pillowcases.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Paper table covers, bedsheets, pillowcases... REQUIREMENTS AND PROHIBITIONS UNDER PART 500 § 501.5 Paper table covers, bedsheets, pillowcases. Table covers, bedsheets, and pillowcases, fabricated from paper, are exempt from the requirements of § 500.12 of this...

Automated energy conserving cover for refrigerated cabinet access openings

International Nuclear Information System (INIS)

Ibrahim, F.F.

1984-01-01

An automatically operated flexible barrier cover for the access openings of refrigerated display cabinets. The barrier cover limits the contact between the refrigerated air within the cabinet and the ambient air. The barrier cover can be moved over the access opening during non-customer use time periods when the retail food outlet is closed. The barrier cover can be arranged as a unitary assembly which can be manufactured and sold separately from the display cabinet as a retrofit device to effect energy savings. The flexible barrier cover can be stored in a reeled-up position or can be arranged as a folded flexible barrier which can be fanned out across the access opening. Various traction means are provided for moving the flexible barrier across the access opening

Nuclear reactor coolant and cover gas system

International Nuclear Information System (INIS)

George, J.A.; Redding, A.H.; Tower, S.N.

1976-01-01

A core cooling system is disclosed for a nuclear reactor of the type utilizing a liquid coolant with a cover gas above free surfaces of the coolant. The disclosed system provides for a large inventory of reactor coolant and a balanced low pressure cover gas arrangement. A flow restricting device disposed within a reactor vessel achieves a pressure of the cover gas in the reactor vessel lower than the pressure of the reactor coolant in the vessel. The low gas pressure is maintained over all free surfaces of the coolant in the cooling system including a coolant reservoir tank. Reactor coolant stored in the reservoir tank allows for the large reactor coolant inventory provided by the invention

Technical specification for fabrication of HANARO pool cover

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jeong Soo; Woo, Sang Ik

2001-06-01

This technical specification details the requirements and the acceptance criteria for design, seismic analysis, function test, installation and quality assurance for HANARO pool cover which will be installed at the top of reactor pool. The pool cover is classified as non-nuclear safety, seismic category II and quality class T. The basic design of the pool cover for increasing HANARO applications has been carried out for supporting the driving devices which can load, unload and rotate the irradiation targets in the in-core and out-core vertical irradiation holes under on-power operation. The comments of HANARO user group related with irradiation tests have optimally considered in the process of design. The interference between fuel handling and control absorber units in the reactor pool and activities to load, unload and rotate the irradiation targets at the top of the reactor pool have been minimized. The pool cover can be moved for maintenance and can protect the reactor pool from unexpected drop of foreign materials. It provides the space to vertical access of driving devices for NTD, CT/IR and OR4/OR5 under on-power operation. And the pool cover assembly must maintain its structural integrity under seismic load. Based on the above design concept, the HANARO pool cover has been proposed as supporting structure of driving devices for NTD, fission moly and RI production under on-power operation.

Temporal Land Cover Analysis for Net Ecosystem Improvement

Energy Technology Data Exchange (ETDEWEB)

Ke, Yinghai; Coleman, Andre M.; Diefenderfer, Heida L.

2013-04-09

We delineated 8 watersheds contributing to previously defined river reaches within the 1,468-km2 historical floodplain of the tidally influenced lower Columbia River and estuary. We assessed land-cover change at the watershed, reach, and restoration site scales by reclassifying remote-sensing data from the National Oceanic and Atmospheric Administration Coastal Change Analysis Program’s land cover/land change product into forest, wetland, and urban categories. The analysis showed a 198.3 km2 loss of forest cover during the first 6 years of the Columbia Estuary Ecosystem Restoration Program, 2001–2006. Total measured urbanization in the contributing watersheds of the estuary during the full 1996-2006 change analysis period was 48.4 km2. Trends in forest gain/loss and urbanization differed between watersheds. Wetland gains and losses were within the margin of error of the satellite imagery analysis. No significant land cover change was measured at restoration sites, although it was visible in aerial imagery, therefore, the 30-m land-cover product may not be appropriate for assessment of early-stage wetland restoration. These findings suggest that floodplain restoration sites in reaches downstream of watersheds with decreasing forest cover will be subject to increased sediment loads, and those downstream of urbanization will experience effects of increased impervious surfaces on hydrologic processes.

CORINE land cover and floristic variation in a Mediterranean wetland.

Science.gov (United States)

Giallonardo, Tommaso; Landi, Marco; Frignani, Flavio; Geri, Francesco; Lastrucci, Lorenzo; Angiolini, Claudia

2011-11-01

The aims of the present study were to: (1) investigate whether CORINE land cover classes reflect significant differences in floristic composition, using a very detailed CORINE land cover map (scale 1:5000); (2) decompose the relationships between floristic assemblages and three groups of explanatory variables (CORINE land cover classes, environmental characteristics and spatial structure) into unique and interactive components. Stratified sampling was used to select a set of 100-m(2) plots in each land cover class identified in the semi-natural wetland surrounding a lake in central Italy. The following six classes were considered: stable meadows, deciduous oak dominated woods, hygrophilous broadleaf dominated woods, heaths and shrublands, inland swamps, canals or watercourses. The relationship between land cover classes and floristic composition was tested using several statistical techniques in order to determine whether the results remained consistent with different procedures. The variation partitioning approach was applied to identify the relative importance of three groups of explanatory variables in relation to floristic variation. The most important predictor was land cover, which explained 20.7% of the variation in plant distribution, although the hypothesis that each land cover class could be associated with a particular floristic pattern was not verified. Multi Response Permutation Analysis did not indicate a strong floristic separability between land cover classes and only 9.5% of species showed a significant indicator value for a specific land cover class. We suggest that land cover classes linked with hygrophilous and herbaceous communities in a wetland may have floristic patterns that vary with fine scale and are not compatible with a land cover map.

26 CFR 31.3121(j)-1 - Covered transportation service.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Covered transportation service. 31.3121(j)-1... § 31.3121(j)-1 Covered transportation service. (a) Transportation systems acquired in whole or in part... operation of a public transportation system constitutes covered transportation service if any part of the...

T Tank Farm Interim Cover Test - Design Plan

International Nuclear Information System (INIS)

Zhang, Z. F.; Keller, Jason M.

2006-01-01

The Hanford Site has 149 underground single-shell tanks that store hazardous radioactive waste. Many of these tanks and their associated infrastructure (e.g., pipelines, diversion boxes) have leaked. Some of the leaked waste has entered the groundwater. The largest known leak occurred from the T-106 Tank in 1973. Many of the contaminants from that leak still reside within the vadose zone beneath the T Tank Farm. CH2M Hill Hanford Group, Inc. seeks to minimize movement of this residual contaminant plume by placing an interim cover on the surface. Such a cover is expected to prevent infiltrating water from reaching the plume and moving it further. Pacific Northwest National Laboratory has prepared a design plan to monitor and determine the effectiveness of the interim cover. A three-dimensional numerical simulation of water movement beneath a cover was conducted to guide the design of the plan. Soil water content, water pressure, and temperature will be monitored using off-the-shelf equipment that can be installed by the hydraulic hammer technique. In fiscal year 2006, two instrument nests will be installed, one inside and one outside of the proposed cover. In fiscal year 2007, two additional instrument nests, both inside the proposed cover, will be installed. Each instrument nest contains a neutron access tube and a capacitance probe (to measure water content), and four heat-dissipation units (to measure pressure head and temperature). A datalogger and a meteorological station will be installed outside of the fence. Two drain gauges will be installed in locations inside and outside the cover for the purpose of measuring soil water flux.

How nest translocation-time, clutch size and presence of yolkless eggs affected hatching success in Dermochelys coriacea (Linnaeus, 1766 (Testudines: Dermochelyidae, at Projeto Tamar-Ibama, Espirito Santo, Brazil

Directory of Open Access Journals (Sweden)

Dal Pont Morisso, Eduardo

2004-07-01

Full Text Available En este estudio se analizó el manejo de los nidos de la especie Dermochelys coriacea, utilizados por el Proyecto Tamar-Ibama entre las temporadas reproductivas de 1989/1990 a 1998/1999, para verificación del éxito de la eclosión en relación a los tiempos de traslación. El estudio se realizó en el litoral norte del Estado de Espírito Santo. Existió tendencia a que el tiempo de traslación influencie el éxito de eclosión de los nidos. Los nidos trasladados entre 6 y más de 24 horas presentaron mayor cantidad de huevos sin desarrollo embrionario. No se encontró relación entre el número de huevos inviables trasladados y el tamaño de la postura, con el porcentual de eclosión. Se sugiere que la traslación sea realizada hasta las 6 horas, o 15 días después de la oviposición. The results of managing Dermochelys coriacea (Linnaeus, 1766 nests by Projeto TAMAR - IBAMA, in Northern Espírito Santo, Brazil, during the nesting seasons from 1989/90 to 1998/99 are analyzed. The influence of the translocation time on hatching success of the studied nests is discussed. The time translocation, in relation to natural oviposition, seems to increase the number of non-developed eggs found in each nest if translocated between 6 hours and 15 days post egg-laying. There was no relationship established between either the number of yolkless eggs in a translocated nest or the clutch size, with hatching success. The translocation of Dermochelys nests either within 6 hours or after 15 days from natural oviposition is recommended.

Cover crops support ecological intensification of arable cropping systems

Science.gov (United States)

Wittwer, Raphaël A.; Dorn, Brigitte; Jossi, Werner; van der Heijden, Marcel G. A.

2017-02-01

A major challenge for agriculture is to enhance productivity with minimum impact on the environment. Several studies indicate that cover crops could replace anthropogenic inputs and enhance crop productivity. However, so far, it is unclear if cover crop effects vary between different cropping systems, and direct comparisons among major arable production systems are rare. Here we compared the short-term effects of various cover crops on crop yield, nitrogen uptake, and weed infestation in four arable production systems (conventional cropping with intensive tillage and no-tillage; organic cropping with intensive tillage and reduced tillage). We hypothesized that cover cropping effects increase with decreasing management intensity. Our study demonstrated that cover crop effects on crop yield were highest in the organic system with reduced tillage (+24%), intermediate in the organic system with tillage (+13%) and in the conventional system with no tillage (+8%) and lowest in the conventional system with tillage (+2%). Our results indicate that cover crops are essential to maintaining a certain yield level when soil tillage intensity is reduced (e.g. under conservation agriculture), or when production is converted to organic agriculture. Thus, the inclusion of cover crops provides additional opportunities to increase the yield of lower intensity production systems and contribute to ecological intensification.

Impacts of Land Cover Changes on Climate over China

Science.gov (United States)

Chen, L.; Frauenfeld, O. W.

2014-12-01

Land cover changes can influence regional climate through modifying the surface energy balance and water fluxes, and can also affect climate at large scales via changes in atmospheric general circulation. With rapid population growth and economic development, China has experienced significant land cover changes, such as deforestation, grassland degradation, and farmland expansion. In this study, the Community Earth System Model (CESM) is used to investigate the climate impacts of anthropogenic land cover changes over China. To isolate the climatic effects of land cover change, we focus on the CAM and CLM models, with prescribed climatological sea surface temperature and sea ice cover. Two experiments were performed, one with current vegetation and the other with potential vegetation. Current vegetation conditions were derived from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite observations, and potential vegetation over China was obtained from Ramankutty and Foley's global potential vegetation dataset. Impacts of land cover changes on surface air temperature and precipitation are assessed based on the difference of the two experiments. Results suggest that land cover changes have a cold-season cooling effect in a large region of China, but a warming effect in summer. These temperature changes can be reconciled with albedo forcing and evapotranspiration. Moreover, impacts on atmospheric circulation and the Asian Monsoon is also discussed.

IMPACT OF HATCH-DATE ON EARLY LIFE GROWTH AND SURVIVAL OF MUELLER’S PEARLSIDE (MAUROLICUS MUELLERI) LARVAE, AND LIFE-HISTORY CONSEQUENCES

KAUST Repository

Folkvord, Arild

2015-08-11

Growth and survival of Maurolicus muelleri larvae in Herdlefjorden, Norway were investigated by daily otolith increment analysis. While high egg densities were generally observed throughout the spawning season, three cohorts each with a narrow window of hatching dates were identified. The first of these cohorts was characterized by low growth and poor morphometric condition and disappeared from the fjord during autumn. High resolution drift modeling indicated that Herdlefjorden had a net export of larvae and negligible import in the period cohort 1 disappeared. Yet, the advective loss rate of larvae was not considered high enough to explain the near complete disappearance of the first cohort. An otolith based growth chronology indicated that growth conditions in Herdlefjorden improved noticeably around mid-September, and remained favorable the following month. The analysis of daily otolith increments could thus be used to document within-season variability in larval growth and survival. The low and variable survival due to short term fluctuations in environmental conditions indicate that multiple batch spawning is an adequately evolved life history strategy for marine planktivorous fish such as M. muelleri.

ON f-EDGE COVER-COLOURING OF SIMPLE GRAPHS

Institute of Scientific and Technical Information of China (English)

Song Huimin; Liu Guizhen

2005-01-01

An f-edge cover-colouring of a graph G = (V, E) is an assignment of colours to the edges of G such that every colour appears at each vertex υ∈ V at least f(υ) times.The maximum number of colours needed to f-edge cover colour G is called the f-edge cover chromatic index of G, denoted by χfc(G). This paper gives that min[d(ν)-1/f(ν)] ≤χfc(G) ≤min[d(υ)/f(υ)].

MATERIALS FOR THE FINAL COVER OF SANITARY LANDFILLS

OpenAIRE

Davorin Kovačić

1994-01-01

The paper deals with the selection of materials for the sea¬ling layer in the final cover of sanitary landfills. The sealing la¬yer is the most critical component of the final cover. Its role is to minimize percolation of water through the final cover. Ma¬terials used for the construction of the sealing layer are either of mineral origin (compacted clay) or geosynthetic (geomem¬brane). They are most often used in combination creating com¬posite liners. Recently alternative materials are also ...

Sky cover from MFRSR observations

Directory of Open Access Journals (Sweden)

E. Kassianov

2011-07-01

Full Text Available The diffuse all-sky surface irradiances measured at two nearby wavelengths in the visible spectral range and their modeled clear-sky counterparts are the main components of a new method for estimating the fractional sky cover of different cloud types, including cumuli. The performance of this method is illustrated using 1-min resolution data from a ground-based Multi-Filter Rotating Shadowband Radiometer (MFRSR. The MFRSR data are collected at the US Department of Energy Atmospheric Radiation Measurement (ARM Climate Research Facility (ACRF Southern Great Plains (SGP site during the summer of 2007 and represent 13 days with cumuli. Good agreement is obtained between estimated values of the fractional sky cover and those provided by a well-established independent method based on broadband observations.

Modeled impact of anthropogenic land cover change on climate

Science.gov (United States)

Findell, K.L.; Shevliakova, E.; Milly, P.C.D.; Stouffer, R.J.

2007-01-01

Equilibrium experiments with the Geophysical Fluid Dynamics Laboratory's climate model are used to investigate the impact of anthropogenic land cover change on climate. Regions of altered land cover include large portions of Europe, India, eastern China, and the eastern United States. Smaller areas of change are present in various tropical regions. This study focuses on the impacts of biophysical changes associated with the land cover change (albedo, root and stomatal properties, roughness length), which is almost exclusively a conversion from forest to grassland in the model; the effects of irrigation or other water management practices and the effects of atmospheric carbon dioxide changes associated with land cover conversion are not included in these experiments. The model suggests that observed land cover changes have little or no impact on globally averaged climatic variables (e.g., 2-m air temperature is 0.008 K warmer in a simulation with 1990 land cover compared to a simulation with potential natural vegetation cover). Differences in the annual mean climatic fields analyzed did not exhibit global field significance. Within some of the regions of land cover change, however, there are relatively large changes of many surface climatic variables. These changes are highly significant locally in the annual mean and in most months of the year in eastern Europe and northern India. They can be explained mainly as direct and indirect consequences of model-prescribed increases in surface albedo, decreases in rooting depth, and changes of stomatal control that accompany deforestation. ?? 2007 American Meteorological Society.

Stakes and modalities of the climatic risk covering

International Nuclear Information System (INIS)

Marteau, D.

2006-01-01

Several econometric works show that climatic volatility is at the first rank of the risk factors in several economic sectors like energy, textile, agriculture and food, tourism, leisure, building industries etc. However, climate remains an underestimated economic factor for several reasons: lack of awareness about the comparative stakes of climate risks management and market risks management, difficulties in the measurement of climate risk exposure, weak knowledge of covering techniques for private contract and organized markets, and unsolved question of risk sharing between shareholders and managers. This document analyzes the sensitivity of companies with respect to climate risk and describes the 5 steps of implementation of a climate covering policy: risk exposure measurement, risk bearing or transfer decision, definition of the optimum covering profile, choice of markets and covering instruments, efficiency measurement. A practical example is shown with its related questions. (J.S.)

Design and Installation of a Disposal Cell Cover Field Test

Energy Technology Data Exchange (ETDEWEB)

Benson, C.H. [University of Wisconsin–Madison, Madison, Wisconsin; Waugh, W.J. [S.M. Stoller Corporation, Grand Junction, Colorado; Albright, W.H. [Desert Research Institute, Reno, Nevada; Smith, G.M. [Geo-Smith Engineering, Grand Junction, Colorado; Bush, R.P. [U.S. Department of Energy, Grand Junction, Colorado

2011-02-27

The U.S. Department of Energy’s Office of Legacy Management (LM) initiated a cover assessment project in September 2007 to evaluate an inexpensive approach to enhancing the hydrological performance of final covers for disposal cells. The objective is to accelerate and enhance natural processes that are transforming existing conventional covers, which rely on low-conductivity earthen barriers, into water balance covers, that store water in soil and release it as soil evaporation and plant transpiration. A low conductivity cover could be modified by deliberately blending the upper layers of the cover profile and planting native shrubs. A test facility was constructed at the Grand Junction, Colorado, Disposal Site to evaluate the proposed methodology. The test cover was constructed in two identical sections, each including a large drainage lysimeter. The test cover was constructed with the same design and using the same materials as the existing disposal cell in order to allow for a direct comparison of performance. One test section will be renovated using the proposed method; the other is a control. LM is using the lysimeters to evaluate the effectiveness of the renovation treatment by monitoring hydrologic conditions within the cover profile as well as all water entering and leaving the system. This paper describes the historical experience of final covers employing earthen barrier layers, the design and operation of the lysimeter test facility, testing conducted to characterize the as-built engineering and edaphic properties of the lysimeter soils, the calibration of instruments installed at the test facility, and monitoring data collected since the lysimeters were constructed.

Soybean growth and yield under cover crops

Directory of Open Access Journals (Sweden)

Priscila de Oliveira

2013-04-01

Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

Cover gases in nuclear reactors with special reference to argon

International Nuclear Information System (INIS)

Jose, C.J.; Shah, G.C.; Prabhu, L.H.; Vartak, D.G.

1975-01-01

The report describes the specifications of an ideal cover gas for the smooth operation of a nuclear reactor. The advantages of using helium as cover gas, the sources of impurities in helium cover gas and the methods of purification of helium are given in detail. Various problems associated with the use of argon as cover gas and methods to purify and decontaminate argon cover gas are discussed on the basis of experimental data collected. A laboratory model of the system which can be used to evaluate the performance of the gas purification adsorbents is also described. (author)

Study on the inside gas flow visualization of oxygen sensor cover; Kashika ni yoru O2 sensor cover nai no gas nagare hyoka

Energy Technology Data Exchange (ETDEWEB)

Hocho, S; Mitsuishi, Y; Inagaki, M [Nippon Soken, Inc., Tokyo (Japan); Hamaguchi, S; Mizusawa, K [Toyota Motor Corp., Aichi (Japan)

1997-10-01

In order to make clear the difference of the response time between the oxygen sensors with different protection covers, we visualized gas flow inside of sensor covers by means of two experimental methods: One is `Smoke Suspension Method` using liquid paraffin vapor as the smoke. With smoke suspension method, we detected the streamlines inside of the covers. The other is `Color Reaction Method` using the reaction of phenolphthalein and NH3 gas. With color reaction method, we confirmed the streamline inside of the cover and furthermore detected the difference of the response time of each sensor. 3 refs., 7 figs., 1 tab.

49 CFR 192.327 - Cover.

Science.gov (United States)

2010-10-01

... locations 36 (914) 24 (610) Drainage ditches of public roads and railroad crossings 36 (914) 24 (610) (b... least 24 inches (610 millimeters) of cover. (c) Where an underground structure prevents the installation...

Covering tree with stars

DEFF Research Database (Denmark)

Baumbach, Jan; Guo, Jian-Ying; Ibragimov, Rashid

2013-01-01

We study the tree edit distance problem with edge deletions and edge insertions as edit operations. We reformulate a special case of this problem as Covering Tree with Stars (CTS): given a tree T and a set of stars, can we connect the stars in by adding edges between them such that the resulting ...

Oxygen diffusion through soil covers on sulphidic mine tailings

International Nuclear Information System (INIS)

Yanful, E.K.

1993-01-01

Engineered soil covers are being evaluated under Canada's Mine Environment Neutral Drainage (MEND) program for their effectiveness in preventing and controlling acid generation in sulfidic mill tailings. A critical parameter for predicting the performance of these covers is the diffusion coefficient of gaseous oxygen in the cover materials. Laboratory experiments conducted to determine the effective diffusion coefficient of a candidate cover material, a glacial till from an active mine site, are described. The diffusion coefficient is determined by fitting a semianalytic solution of the one-dimensional, transient diffusion equation to experimental gaseous oxygen concentration versus time graphs. Effective diffusion coefficients determined at high water saturations (85%--95%) were of the order of 8 x 10 -8 m 2 /s. The diffusion coefficients decreased with increase in water saturation as a result of the low diffusivity of gaseous oxygen in water relative to that in air and the low solubility of oxygen in water. Placement of soil covers in high saturation conditions would ensure that the flux of oxygen into tailings underneath such covers is low, resulting in low acid flux. This is confirmed by combined laboratory, field, and modeling studies

Interfacial stability of soil covers on lined surface impoundments

International Nuclear Information System (INIS)

Mitchell, D.H.; Gates, T.E.

1986-04-01

The factors affecting the interfacial stability of soil covers on geomembranes were examined to determine the maximum stable slopes for soil cover/geomembrane systems. Several instances of instability of soil covers on geomembranes have occurred at tailings ponds, leaving exposed geomembranes with the potential for physical ddamage and possibly chemical and ultraviolet degradation. From an operator's viewpoint, it is desirable to maximize the slope of lined facilities in order to maximize the volume-to-area ratio; however, the likelihood for instability also increases with increasing slope. Frictional data obtained from direct shear tests are compared with stability data obtained using a nine-square-meter (m 2 ) engineering-scale test stand to verify that direct shear test data are valid in slope design calculations. Interfacial frictional data from direct shear tests using high-density polyethylene and a poorly graded sand cover agree within several degrees with the engineering-scale tests. Additional tests with other soils and geomembranes are planned. The instability of soil covers is not always an interfacial problem; soil erosion and limited drainage capacity are additional factors that must be considered in the design of covered slopes. 7 refs., 5 figs., 2 tabs

Cover Image, Volume 233, Number 7, July 2018.

Science.gov (United States)

Yin, Chong; Zhang, Yan; Hu, Lifang; Tian, Ye; Chen, Zhihao; Li, Dijie; Zhao, Fan; Su, Peihong; Ma, Xiaoli; Zhang, Ge; Miao, Zhiping; Wang, Liping; Qian, Airong; Xian, Cory J

2018-07-01

Cover: The cover image, by Yin et al., is based on the Original Research Article, Mechanical unloading reduces microtubule actin crosslinking factor 1 expression to inhibit β-Catenin Signaling and osteoblast proliferation, DOI: 10.1002/jcp.26374. © 2018 Wiley Periodicals, Inc.

Cover song identification by sequence alignment algorithms

Science.gov (United States)

Wang, Chih-Li; Zhong, Qian; Wang, Szu-Ying; Roychowdhury, Vwani

2011-10-01

Content-based music analysis has drawn much attention due to the rapidly growing digital music market. This paper describes a method that can be used to effectively identify cover songs. A cover song is a song that preserves only the crucial melody of its reference song but different in some other acoustic properties. Hence, the beat/chroma-synchronous chromagram, which is insensitive to the variation of the timber or rhythm of songs but sensitive to the melody, is chosen. The key transposition is achieved by cyclically shifting the chromatic domain of the chromagram. By using the Hidden Markov Model (HMM) to obtain the time sequences of songs, the system is made even more robust. Similar structure or length between the cover songs and its reference are not necessary by the Smith-Waterman Alignment Algorithm.

UMTRAP research on cover design for uranium mill tailings

International Nuclear Information System (INIS)

Rogers, V.C.; Nielson, K.K.

1984-01-01

As a result of the UMTRAP research on radon attenuation and tailings cover design, the basis and general procedures are available for designing covers for uranium tailings piles to meet present criteria for radon emissions. The general procedures involve assessment of the radon source strength of the tailings, definition of candidate cover materials, assessment of their moisture retention and radon diffusion properties, computing the required thicknesses of these materials, comparing costs, and evaluating long-term performance criteria. Final selection of the cover design must assure adequate long-term performance and radon retention as first priority, and keep costs to a minimum in achieving this goal

Component failure experiments of the seal casing for the multiple-row bolted connection of the containment equipment hatch of the nuclear power plant Philippsburg II; Experimente zum Versagen des Dichtkastens fuer die Materialschleusenverschraubung im Containment des KKW Philippsburg II

Energy Technology Data Exchange (ETDEWEB)

Messemer, G.

2008-06-15

For the weakness analysis of the containment under internal pressure a question that arose was at what pressure the seal casing for the equipment hatch will fail. For this investigation model strips of the seal casing cross section were manufactured as tensile specimens. Variations of the seal plates welding seams were considered and tested. The type of failure and the associated deformations and resulting forces were measured for 6 specimens. (orig.)

Integration of multiple, excess, backup, and expected covering models

OpenAIRE

M S Daskin; K Hogan; C ReVelle

1988-01-01

The concepts of multiple, excess, backup, and expected coverage are defined. Model formulations using these constructs are reviewed and contrasted to illustrate the relationships between them. Several new formulations are presented as is a new derivation of the expected covering model which indicates more clearly the relationship of the model to other multi-state covering models. An expected covering model with multiple time standards is also presented.

Estimation of snow cover distribution in Beas basin, Indian Himalaya ...

Indian Academy of Sciences (India)

In the present paper, a methodology has been developed for the mapping of snow cover in Beas ... Different snow cover mapping methods using snow indices are compared to find the suitable ... cover are important factors for human activities,.

Development of 2010 national land cover database for the Nepal.

Science.gov (United States)

Uddin, Kabir; Shrestha, Him Lal; Murthy, M S R; Bajracharya, Birendra; Shrestha, Basanta; Gilani, Hammad; Pradhan, Sudip; Dangol, Bikash

2015-01-15

Land cover and its change analysis across the Hindu Kush Himalayan (HKH) region is realized as an urgent need to support diverse issues of environmental conservation. This study presents the first and most complete national land cover database of Nepal prepared using public domain Landsat TM data of 2010 and replicable methodology. The study estimated that 39.1% of Nepal is covered by forests and 29.83% by agriculture. Patch and edge forests constituting 23.4% of national forest cover revealed proximate biotic interferences over the forests. Core forests constituted 79.3% of forests of Protected areas where as 63% of area was under core forests in the outside protected area. Physiographic regions wise forest fragmentation analysis revealed specific conservation requirements for productive hill and mid mountain regions. Comparative analysis with Landsat TM based global land cover product showed difference of the order of 30-60% among different land cover classes stressing the need for significant improvements for national level adoption. The online web based land cover validation tool is developed for continual improvement of land cover product. The potential use of the data set for national and regional level sustainable land use planning strategies and meeting several global commitments also highlighted. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cover technology demonstration for low-level radioactive sites

International Nuclear Information System (INIS)

Barnes, F.J.; Warren, J.L.

1988-01-01

The performance of a shallow land burial site in isolating low-level radioactive and mixed waste is strongly influenced by the behavior of the precipitation falling on the site. Predicting the long-term integrity of a cover design requires a knowledge of the water balance dynamics, and the use of predictive models. The multiplicity of factors operating on a site in the years post-closure (precipitation intensity and duration, soil conditions, vegetation seasonality and variability) have made it extremely difficult to predict the effects of natural precipitation with accuracy. Preliminary results are presented on a three-year field demonstration at Los Alamos National Laboratory to evaluate the influence of different waste trench cap designs on water balance under natural precipitation. Erosion plots having two different vegetative covers (shrubs and grasses) and with either gravel-mulched or unmulched soil surface treatments have been established on three different soil profiles on an inactive waste site. Total runoff and soil loss from each plot are measured biweekly while plant canopy cover is measured seasonally. Preliminary results from the first year show that the application of a gravel mulch reduced runoff by 73 to 90%. Total soil loss was reduced by 83 to 93% by the mulch treatment. On unmulched plots, grass cover reduced both runoff and soil loss by about 50% compared to the shrub plots. Soil moisture reduction during the growing season was more pronounced on the shrub plots. This indicates that a more complex vegetative cover provides greater soil moisture storage capacity for winter precipitation than the usual grass cover

Land-cover change in the Ozark Highlands, 1973-2000

Science.gov (United States)

Karstensen, Krista A.

2010-01-01

Led by the Geographic Analysis and Monitoring Program of the U.S. Geological Survey (USGS) in collaboration with the U.S. Environmental Protection Agency (EPA) and the National Aeronautics and Space Administration (NASA), the Land-Cover Trends Project was initiated in 1999 and aims to document the types, geographic distributions, and rates of land-cover change on a region by region basis for the conterminous United States, and to determine some of the key drivers and consequences of the change (Loveland and others, 2002). For 1973, 1980, 1986, 1992, and 2000 land-cover maps derived from the Landsat series are classified by visual interpretation, inspection of historical aerial photography and ground survey, into 11 land-cover classes. The classes are defined to capture land cover that is discernable in Landsat data. A stratified probability-based sampling methodology undertaken within the 84 Omernik Level III Ecoregions (Omernik, 1987) was used to locate the blocks, with 9 to 48 blocks per ecoregion. The sampling was designed to enable a statistically robust 'scaling up' of the sample-classification data to estimate areal land-cover change within each ecoregion (Loveland and others, 2002; Stehman and others, 2005). At the time of writing, approximately 90 percent of the 84 conterminous United States ecoregions have been processed by the Land-Cover Trends Project. Results from these completed ecoregions illustrate that across the conterminous United States there is no single profile of land-cover/land-use change, rather, there are varying pulses affected by clusters of change agents (Loveland and others, 2002). Land-Cover Trends Project results for the conterminous United States to-date are being used for collaborative environmental change research with partners such as; the National Science Foundation, the National Oceanic and Atmospheric Administration, and the U.S. Fish and Wildlife Service. The strategy has also been adapted for use in a NASA global

MATERIALS FOR THE FINAL COVER OF SANITARY LANDFILLS

Directory of Open Access Journals (Sweden)

Davorin Kovačić

1994-12-01

Full Text Available The paper deals with the selection of materials for the sea¬ling layer in the final cover of sanitary landfills. The sealing la¬yer is the most critical component of the final cover. Its role is to minimize percolation of water through the final cover. Ma¬terials used for the construction of the sealing layer are either of mineral origin (compacted clay or geosynthetic (geomem¬brane. They are most often used in combination creating com¬posite liners. Recently alternative materials are also used like paper mill sludge or discarded swelling clay.

Performance of Chicks Submitted to Fasting Post-Hatching and with Maltodextrine Supplementing to Diet as Hydrating and Energetic Additive

Directory of Open Access Journals (Sweden)

CA Machado

Full Text Available ABSTRACT This study aimed to evaluate the effect of maltodextrin on performance of chicks passed through four fasting periods. A completely randomized design was performed, consisting of three treatments (1 - control, 2 - 4% saccharose; 3-4% maltodextrin 20 and four fasting periods after hatching (0, 12, 24 and 36 hours with four replications, totaling 1920 birds of both sexes. The studied variables were: water intake in the first 12 hours, average food intake, average body weight and real feed conversion. Data was submitted to analysis of variance and means were compared with each other by Dunnett test at 5% significance. The use of additives and imposing of different fasting periods did not influence the performance at 42 days old. Therefore, fasted chicks consumed significantly more water. At 7 days old, chicks fasted showed higher body weight and higher feed intake, however, the viability did not suffer any influence, the weight remained higher after 21days with the fast imposition and there was no influence on other variables. There was no effect of fasting on broiler chiken's performance at 42 days old. The inclusion of sucrose and maltodextrin to drinking water stimulated the chick´s water intake and provided higher viability after seven days old.

Land Cover Classification Using ALOS Imagery For Penang, Malaysia

International Nuclear Information System (INIS)

Sim, C K; Abdullah, K; MatJafri, M Z; Lim, H S

2014-01-01

This paper presents the potential of integrating optical and radar remote sensing data to improve automatic land cover mapping. The analysis involved standard image processing, and consists of spectral signature extraction and application of a statistical decision rule to identify land cover categories. A maximum likelihood classifier is utilized to determine different land cover categories. Ground reference data from sites throughout the study area are collected for training and validation. The land cover information was extracted from the digital data using PCI Geomatica 10.3.2 software package. The variations in classification accuracy due to a number of radar imaging processing techniques are studied. The relationship between the processing window and the land classification is also investigated. The classification accuracies from the optical and radar feature combinations are studied. Our research finds that fusion of radar and optical significantly improved classification accuracies. This study indicates that the land cover/use can be mapped accurately by using this approach

12 CFR 207.6 - Disclosure of covered agreements.

Science.gov (United States)

2010-01-01

... DISCLOSURE AND REPORTING OF CRA-RELATED AGREEMENTS (REGULATION G) § 207.6 Disclosure of covered agreements... CRA public file by insured depository institution or affiliate. An insured depository institution and...) by placing a copy of the covered agreement in the insured depository institution's CRA public file if...

"(Un)covering" in the Classroom: Managing Stigma beyond the Closet

Science.gov (United States)

Branfman, Jonathan

2017-01-01

While many instructors closet stigmatized identities, others "downplay" them--a tactic that sociologist Erving Goffman terms "covering." What are the personal, ethical, and pedagogical costs of covering? What are the gains? How can feminist university instructors cover stigmatized identities without fueling oppressive…

Estimating pinyon and juniper cover across Utah using NAIP imagery

Directory of Open Access Journals (Sweden)

Darrell B. Roundy

2016-11-01

Full Text Available Expansion of Pinus L. (pinyon and Juniperus L. (juniper (P-J trees into sagebrush (Artemisia L. steppe communities can lead to negative effects on hydrology, loss of wildlife habitat, and a decrease in desirable understory vegetation. Tree reduction treatments are often implemented to mitigate these negative effects. In order to prioritize and effectively plan these treatments, rapid, accurate, and inexpensive methods are needed to estimate tree canopy cover at the landscape scale. We used object based image analysis (OBIA software (Feature AnalystTM for ArcMap 10.1®, ENVI Feature Extraction®, and Trimble eCognition Developer 8.2® to extract tree canopy cover using NAIP (National Agricultural Imagery Program imagery. We then compared our extractions with ground measured tree canopy cover (crown diameter and line point intercept on 309 plots across 44 sites in Utah. Extraction methods did not consistently over- or under-estimate ground measured P-J canopy cover except where tree cover was >45%. Estimates of tree canopy cover using OBIA techniques were strongly correlated with estimates using the crown diameter method (r = 0.93 for ENVI, 0.91 for Feature AnalystTM, and 0.92 for eCognition. Tree cover estimates using OBIA techniques had lower correlations with tree cover measurements using the line-point intercept method (r = 0.85 for ENVI, 0.83 for Feature AnalystTM, and 0.83 for eCognition. All software packages accurately and inexpensively extracted P-J canopy cover from NAIP imagery when the imagery was not blurred, and when P-J cover was not mixed with Amelanchier alnifolia (Utah serviceberry and Quercus gambelii (Gambel’s oak, which had similar spectral values as P-J.