WorldWideScience

Sample records for channa striata bloch

  1. GROWTH AND EXPLOITATION STATUS (Channa striata Bloch, 1793 IN LUBUK LAMPAM FLOODPLAINS, SOUTH SUMATERA

    Directory of Open Access Journals (Sweden)

    Zulkarnaen Fahmi

    2013-06-01

    Full Text Available Due to the economic importance of C. striata in Lubuk Lampam floodplains (Indonesia, this study is aimed to estimate the biological and population parameters required for proposing a future plan to sustain and manage this valuable fish resource. The growth, mortality and explotation ratio of Channa striata estimated by employing FiSATProgramme are reported. The parameters of Von Bertalanffy growth model of 1,529 sample fishes were estimated as K= 0.36/ year, L” = 72.98 cm and to = -0.52 year. The coefficients of total mortality (Z, natural mortality (M and fishing mortality (F were 1.72, 0.73 and 0.99 year-1 respectively. Relative yield per recruit analysis shows that the presentexploitation rate (E was 0.58. Yield per recruit can be maximized at the exploitation ratio of 0.5 and Lc/Linf values of 0.3. The Yield per recruit and biomass per recruit models indicated that, the fisheries status of C. striata in Lubuk Lampam floodplains exceed the limit reference point (Fmax, thus stock of this species in Lubuk Lampam floodplains is indicated being driving down.Reduction in fishing effort and increase number of selective fishing gears are suggested to sustain the fishery of Channa striata in Lubuk Lampam floodplains.

  2. Characterisation of Asian Snakehead Murrel Channa striata (Channidae) in Malaysia: An Insight into Molecular Data and Morphological Approach

    Science.gov (United States)

    Song, Li Min; Munian, Kaviarasu; Abd Rashid, Zulkafli; Bhassu, Subha

    2013-01-01

    Conservation is imperative for the Asian snakeheads Channa striata, as the species has been overfished due to its high market demand. Using maternal markers (mitochondrial cytochrome c oxidase subunit 1 gene (COI)), we discovered that evolutionary forces that drove population divergence did not show any match between the genetic and morphological divergence pattern. However, there is evidence of incomplete divergence patterns between the Borneo population and the populations from Peninsular Malaysia. This supports the claim of historical coalescence of C. striata during Pleistocene glaciations. Ecological heterogeneity caused high phenotypic variance and was not correlated with genetic variance among the populations. Spatial conservation assessments are required to manage different stock units. Results on DNA barcoding show no evidence of cryptic species in C. striata in Malaysia. The newly obtained sequences add to the database of freshwater fish DNA barcodes and in future will provide information relevant to identification of species. PMID:24396312

  3. Characterisation of Asian Snakehead Murrel Channa striata (Channidae in Malaysia: An Insight into Molecular Data and Morphological Approach

    Directory of Open Access Journals (Sweden)

    Li Min Song

    2013-01-01

    Full Text Available Conservation is imperative for the Asian snakeheads Channa striata, as the species has been overfished due to its high market demand. Using maternal markers (mitochondrial cytochrome c oxidase subunit 1 gene (COI, we discovered that evolutionary forces that drove population divergence did not show any match between the genetic and morphological divergence pattern. However, there is evidence of incomplete divergence patterns between the Borneo population and the populations from Peninsular Malaysia. This supports the claim of historical coalescence of C. striata during Pleistocene glaciations. Ecological heterogeneity caused high phenotypic variance and was not correlated with genetic variance among the populations. Spatial conservation assessments are required to manage different stock units. Results on DNA barcoding show no evidence of cryptic species in C. striata in Malaysia. The newly obtained sequences add to the database of freshwater fish DNA barcodes and in future will provide information relevant to identification of species.

  4. Brain cholinesterase response in the snakehead fish (Channa striata) after field exposure to diazinon

    DEFF Research Database (Denmark)

    van Cong, Nguyen; Phuong, Nguyen Thanh; Bayley, Mark

    2008-01-01

    commonly used chemicals in rice paddies. In the present study, exposure of adult snakehead fish to a single diazinon application in cages within a rice field resulted in long-term brain cholinesterase inhibition, while the water concentration of this insecticide fell below the detection limit within 3 days......The snakehead Channa striata is an economically important air-breathing fish species in the Mekong delta of Vietnam. Rice paddies, which are disturbed by the frequent application of agro-chemicals, are among the preferred habitats for this species during the rainy season. Diazinon is one of most...

  5. Exiguobacterium mediated arsenic removal and its protective effect against arsenic induced toxicity and oxidative damage in freshwater fish, Channa striata

    Directory of Open Access Journals (Sweden)

    Neha Pandey

    2015-01-01

    Full Text Available Arsenic is a toxic metalloid existing widely in the environment, and its removal from contaminated water has become a global challenge. The use of bacteria in this regard finds a promising solution. In the present study, Exiguobacterium sp. As-9, which is an arsenic resistant bacterium, was selected with respect to its arsenic removal efficiency. Quantification of arsenic in the water treated with bacterium showed that Exiguobacterium efficiently removed up to 99% of arsenic in less than 20 h. In order to reveal the possible effect of this bacterium in removal of arsenic from water and protecting fishes from the detrimental effects of arsenic, we initiated a range of studies on fresh water fish, Channa striata. It was observed that the fishes introduced into bacteria treated water displayed no symptoms of arsenic toxicity which was marked by a decreased oxidative damage, whereas the fishes exposed to arsenic revealed a significant (p < 0.05 increase in the oxidative stress together with the elevated levels of malondialdehyde. Determination of the bioaccumulation of arsenic in the liver tissues of C. striata using hydride generation atomic absorption spectrophotometry (HG-AAS revealed an increased As(III accumulation in the fishes exposed to arsenic whereas the arsenic level in the control and bacteria treated fishes were found below the detectable limit. In conclusion, this study presents the strategies of bacterial arsenic removal with possible directions for future research.

  6. Cyclic variations of gonad development of an air-breathing fish, Channa striata in the lentic and lotic environments

    Directory of Open Access Journals (Sweden)

    Nasim Al Mahmud

    2016-03-01

    Full Text Available Abstract The study was conducted to know the cyclic changes in gonadal maturation and to investigate the developmental stages of oocytes and testicular germ cells of an air-breathing fish, Channa striata. Fish were sampled monthly from lentic and lotic environments of three geographical locations of Bangladesh from December to November and the histological analysis of their gonad was done to evaluate the objectives. The highest mean GSI was 5.95 ± 0.20 for female in July and 0.14 ± 0.01 for male also in July showing that the gonadal development reached its peak during this month. The highest mean oocyte diameter was 1257.50 ± 24.17 μm observed in July implying that the oocyte reached maturity in this month. Histological study of ovary revealed the evidence of early yolk granule stage and late yolk granule stage from April to July. In case of male four stages of spermatogenesis were distinguished and spermatozoa were highly abundant in June and July. So the monthly pooled values of GSI and the analysis of gonadal histology indicated that the peak breeding season of C. striata occurred in July in the lentic and lotic environments. Samples collected from lentic and lotic habitats are suggestive of no difference in the development of the gonad. The results of the present study will be useful for selective breeding programme, conservation and sustainable fishery management of C. striata in its natural habitat.

  7. The influence of snakehead (Channa striata) fish extract to increase hyperglycemic mice fertility based on spermatogenic cell composition

    Science.gov (United States)

    Hidayati, Dewi; Abdulgani, Nurlita; Ashuri, Nova Maulidina; Sa'adah, Noor Nailis; Lukitasari, Maharani

    2017-06-01

    Reproductive dysfunction is recognized as a consequence of diabetes mellitus. Previous study revealed that snakehead (Channa striata) fish extract can repairing the pancreas histological structure which by that decreasing the blood glucose levels. Further research was conducted to determine the influence of snakehead fish extract (SHFE) to increasing the fertility of hyperglycemic mice based on spermatogenic cell composition. Twenty five adult mice (Mus musculus) were induced intraperitoneally to be hyperglycemic using alloxan monohydrate single dose of 190 mg/kg body weight. Hyperglycemic mice treated orally for 14 days using SHFE which grouped into five treatment dosages. Testicular histology were prepared using the paraffin methods and stained with Haematoxylin and Eosin. According to ANOVA and Tukey's test, it was found that spermatogenic cells population as well as its composition in the testis of mice that treated with SHFE are significantly higher than hyperglichemic mice. The highest dose of SHFE (0.15 ml/day), showed highest spermatogenic cell. All hyperglichemic mice that treated with SHFE exhibited the ratio composition of spermatogonia: spermatocytes: spermatids as same as with control (healthy mice) i.e. 1:1:3 respectively.

  8. Cytotoxic and genotoxic affects of acid mine drainage on fish Channa punctata (Bloch).

    Science.gov (United States)

    Talukdar, B; Kalita, H K; Basumatary, S; Saikia, D J; Sarma, D

    2017-10-01

    The investigation deals with the effects of Acid Mine Drainage (AMD) of coal mine on fish Channa punctata (Bloch) by examining the incidence of haematological, morphological, histological changes and DNA fragmentation in tissues of C. punctata in laboratory condition. For this study fishes were exposed to 10% of AMD for a period of 30 days. The fusion of the primary and secondary gill lamellae, distortion, loss of alignment, deposition of worn out tissues and mucous on the surface of the lamella in the gills; degeneration of morphological architecture, loss of alignment of tubules, mucous deposition in the kidney; cellular damage, cellular necrosis, extraneous deposition on the surface, pore formation in the liver are some important changes detected by scanning electron microscopy. Fishes of AMD treated group showed gradual significant decrease in TEC, Hb and, increase in TLC and DLC as compared to that of the control. DNA fragmentation observed in kidney of fishes from treated group indicates an intricate pollutant present in the AMD. The high incidence of morphological and histological alterations, haematological changes along with DNA breakage in C. punctata is an evidence of the cytotoxic and genotoxic potential of AMD of coal mines. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Antimicrobial activity of different tissues of snakehead fish Channa striatus (Bloch

    Directory of Open Access Journals (Sweden)

    Pravin Kumar N

    2012-05-01

    Full Text Available Objective: The aim of this study was to identify the presence of antimicrobial activity in different organs/tissues (gills, blood, skin, liver, intestine, kidney, tissue and ovary extract of snakehead fish Channa striatus. Methods: A total of 48 fractions from the organs and tissue extracts were obtained by solid-phase extraction and the fractions were assayed for antimicrobial activity. The screening of antimicrobial activity for all the fractions were tested against 8 human pathogens including Gram positive (Methicillin-resistant Staphylococcus aureus (MRSA, Staphylococcus aureus, Bacillus cereus and Gram negative bacteria (Salmonella enteritidis, Shigella flexneri, Acinetobacter baumanni, Escherichia coli, Klebsiella pneumoniae using the British Society for Antimicrobial Chemotherapy (BSAC standardized disc susceptibility test method. The activity was measured in terms of zone of inhibition in mm. Results: The results indicated that, among the 8 organs/tissues tested only blood and gills extract fractions (40 and 60 % ACN fraction showed inhibition against Escherichia coli and 60 % ACN fraction of gill extract showed inhibition against Salmonella enteritidis. Protein profile analysis by SDS-PAGE showed that antimicrobial activity of the partially purified blood and gill tissue extracts might be due to low molecular weight peptides. Conclusions: The present study showed that, gill and blood extracts of Channa striatus can be a potential source of an antimicrobial protein for specific human pathogens.

  10. Hepatic Cytochrome P450 as Biomarkers of Cypermethrin Toxicity in Freshwater Teleost, Channa punctatus (Bloch

    Directory of Open Access Journals (Sweden)

    Dawa Bhutia

    2015-02-01

    Full Text Available In this study, Channa punctatus was treated with sub-lethal concentration of cypermethrin (6.6 µg/L for 5, 10 and 15 days and its effect on total CYP 450 and the activity of hepatic CYP450 isoforms measured. Total CYP450 content and CYP1A mediated EROD activity was significantly induced (p<0.05 in all three treated groups compared to control whereas only 15 days treated group showed significant induction in CYP2B mediated N,Ndimethylaniline demethylase activity. CYP2E1 mediated aniline hydroxylase activity showed only a marginal increase while there was inhibition of CYP3A4 mediated erythromycin demethylase activity. Liver somatic index (LSI also showed a marginal increase in all the treated groups. Results showed differential induction of CYP1A, CYP2B, CYP2E1 and inhibition of CYP3A4 isoform due to cypermethrin treatment in C. punctatus. The study clearly showed CYP1A isoform as the most responsive and important biomarker for monitoring the aquatic pollution.

  11. Comparison of Selected Metals Content in Cambodian Striped Snakehead Fish (Channa striata Using Solar Drying System and Open Sun Drying

    Directory of Open Access Journals (Sweden)

    Dayang Fredalina Basri

    2015-01-01

    Full Text Available The content of 12 elements in Cambodian dried striped snakehead fish was determined using inductively coupled plasma mass spectrometry. The present study compares the level of the trace toxic metals and nutritional trace elements in the fish processed using solar drying system (SDS and open sun drying (OSD. The skin of SDS fish has lower level of As, Pb, and Cd compared to the OSD sample. As such, the flesh of the fish accumulated higher amount of toxic metals during OSD compared to SDS. However, arsenic was detected in both samples within the safe limit. The nutritional elements (Fe, Mn, Mg, Se, Mo, Cu, Ni, and Cr were higher in the skin sample SDS fish compared to OSD fish. These beneficial metals were not accumulated in the flesh sample SDS fish demonstrating lower level compared to drying under conventional system. The reddish coloration of the SDS fish was due to the presence of high Cu content in both the skin and flesh samples which possibly account for no mold formation 5 days after packaging. As conclusion, drying of Cambodian C. striata using solar-assisted system has proven higher content of the nutritious elements compared to using the conventional system despite only slight difference in the toxic metals level between the two systems.

  12. Comparison of selected metals content in Cambodian striped snakehead fish (Channa striata) using solar drying system and open sun drying.

    Science.gov (United States)

    Basri, Dayang Fredalina; Abu Bakar, Nur Faizah; Fudholi, Ahmad; Ruslan, Mohd Hafidz; Saroeun, Im

    2015-01-01

    The content of 12 elements in Cambodian dried striped snakehead fish was determined using inductively coupled plasma mass spectrometry. The present study compares the level of the trace toxic metals and nutritional trace elements in the fish processed using solar drying system (SDS) and open sun drying (OSD). The skin of SDS fish has lower level of As, Pb, and Cd compared to the OSD sample. As such, the flesh of the fish accumulated higher amount of toxic metals during OSD compared to SDS. However, arsenic was detected in both samples within the safe limit. The nutritional elements (Fe, Mn, Mg, Se, Mo, Cu, Ni, and Cr) were higher in the skin sample SDS fish compared to OSD fish. These beneficial metals were not accumulated in the flesh sample SDS fish demonstrating lower level compared to drying under conventional system. The reddish coloration of the SDS fish was due to the presence of high Cu content in both the skin and flesh samples which possibly account for no mold formation 5 days after packaging. As conclusion, drying of Cambodian C. striata using solar-assisted system has proven higher content of the nutritious elements compared to using the conventional system despite only slight difference in the toxic metals level between the two systems.

  13. Assessment of pollution of river Ganges by tannery effluents using genotoxicity biomarkers in murrel fish, Channa punctatus (Bloch).

    Science.gov (United States)

    Nagpure, N S; Srivastava, Rashmi; Kumar, Ravindra; Dabas, Anurag; Kushwaha, Basdeo; Kumar, Pavan

    2015-07-01

    River pollution due to rapid industrialization and anthropogenic activities adversely affects the aquatic organisms, especially fish. Here, we assessed the genotoxicity, mutagenicity and bioaccumulative aspects of tannery effluents in freshwater murrel, Channa punctatus, an inhabitant of river Ganges. Test specimens were collected from three different polluted sites of the river within and nearby Kanpur area during different seasons and blood samples of these specimens were processed for comet assay and micronucleus test as genotoxicity biomarkers. A significantly (P industry) above the maximum permissible limits as prescribed by World Health Organization (WHO). The findings of the present analysis indicated contamination of river Ganges with tannery effluents which induce genotoxicity in fish with seasonal variation.

  14. Redescription of Henneguya chaudhuryi (Bajpai & Haldar, 1982) (Myxosporea: Myxobolidae), infecting the gills of the freshwater fish Channa punctata (Bloch) (Perciformes: Channidae) in India.

    Science.gov (United States)

    Chaudhary, Anshu; Molnár, Kálmán; Gupta, Abhishek; Cech, Gábor; Singh, Hridaya S; Székely, Csaba

    2017-03-01

    During a survey of myxosporean parasites of freshwater fishes in Meerut, Uttar Pradesh (UP), India, spores of Henneguya chaudhuryi (Bajpai & Haldar, 1982) were found in the gill lamellae of the spotted snakehead fish Channa punctata (Bloch) (Perciformes: Channidae). This species was described lacking several characteristics in the original description, which makes challenging the accurate diagnosis. Here, we supplemented its description based on morphological, histological and molecular data. Plasmodia of H. chaudhuryi are oval, measuring 60-100 × 40-68 µm, located intralamellarly. Mature spores are elongate, measuring 10.5-13.2 × 3.6-4.2 µm, with two slightly unequal polar capsules with 6-7 filamental turns and two straight, equal caudal appendages, 10-17 µm long. Scanning electron microscopy revealed a flat surface. The 18S rDNA sequence for H. chaudhuryi did not show a close relationship with those of any other Henneguya spp., represented in the GenBank.

  15. Chronic exposure to sublethal hexavalent chromium affects organ histopathology and serum cortisol profile of a teleost, Channa punctatus (Bloch)

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Ashish K. [Department of Zoology, University of Allahabad, Allahabad-211002 (India); Mohanty, Banalata, E-mail: drbana_mohanty@rediffmail.com [Department of Zoology, University of Allahabad, Allahabad-211002 (India)

    2009-09-01

    Effects of chronic exposures (one and two months) to sublethal doses of hexavalent chromium (2 and 4 mg/L potassium dichromate) on organ histopathology and serum cortisol profile were investigated and their overall impact on growth and behavior of a teleost fish, Channa punctatus was elucidated. Histopathological lesions were distinct in the vital organs gill, kidney and liver. The gill lamellae became lifted, fused, and showed oedema. Hyperplasia and hypertrophy of lamellar epithelial cells were distinct with desquamation. Hypertrophy of epithelial cells of renal tubules and reduction in tubular lumens were observed in the trunk kidney. The atrophy of the head kidney interrenal cells and decreased serum cortisol level indicated exhaustion of interrenal activity. Hepatocyte vacuolization and shrinkage, nuclear pyknosis and increase of sinusoidal spaces were observed in the liver. Abnormal behavioral patterns and reduced growth rate were also noticed in the exposed fish. The chronic hexavalent chromium exposure thus by affecting histopathology of gill, kidney (including interrenal tissue) and liver could impair the vital functions of respiration, excretion, metabolic regulation and maintenance of stress homeostasis which in the long-run may pose serious threat to fish health and affect their population.

  16. Annual changes in serum calcium and inorganic phosphate levels and correlation with gonadal status of a freshwater murrel, Channa punctatus (Bloch

    Directory of Open Access Journals (Sweden)

    S.K. Srivastav

    1998-08-01

    Full Text Available Adult Channa punctatus murrels of both sexes (60-80 g were collected locally from Ramgarh Lake during the second week of every month (10 individuals of each sex/month throughout the year. Blood samples were collected and analyzed for serum calcium and phosphate levels by the methods of Trinder (1960 and Fiske and Subbarow (1925, respectively. Gonads were fixed to judge the state of maturation of the fish. Males exhibited no change in serum calcium levels throughout the year in correlation with testicular maturation. However, serum phosphate levels exhibited a rise in correlation with the increased gonadosomatic index. Females showed marked seasonal changes in serum calcium and phosphate levels which were associated with ovarian maturation (vitellogenesis.

  17. Toxicity of the Herbicide Atrazine: Effects on Lipid Peroxidation and Activities of Antioxidant Enzymes in the Freshwater Fish Channa Punctatus (Bloch

    Directory of Open Access Journals (Sweden)

    Satish Kumar Srivastava

    2010-08-01

    Full Text Available The present study was undertaken to evaluate the toxicity and effects of a commercial formulation of the herbicide atrazine (Rasayanzine on lipid peroxidation and antioxidant enzyme system in the freshwater air breathing fish Channa punctatus. The 12, 24, 48, 72 and 96 h LC50 of atrazine, calculated by probit analysis, were determined to be 77.091, 64.053, 49.100, 44.412 and 42.381 mg·L-1, respectively, in a semi static system with significant difference (p < 0.05 in LC10-90 values obtained for different times of exposure. In addition to concentration and time dependent decrease in mortality rate, stress signs in the form of behavioral changes were also observed in response to the test chemical. In fish exposed for 15 days to different sublethal concentrations of the herbicide (1/4 LC50 = ~10.600 mg·L-1, 1/8 LC50 = ~5.300 mg·L-1 and 1/10 LC50 = ~4.238 mg·L-1 induction of oxidative stress in the liver was evidence by increased lipid peroxidation levels. The antioxidants superoxide dismutase (SOD, catalase (CAT and glutathione reductase (GR responded positively in a concentration dependent pattern, thus, suggesting the use of these antioxidants as potential biomarkers of toxicity associated with contaminations exposure in freshwater fishes.

  18. STATUS REPRODUKSI IKAN GABUS, Channa striata Blkr (Reproduction status snakehead, Channa striata

    Directory of Open Access Journals (Sweden)

    Untung Bijaksana

    2017-02-01

    Full Text Available Research aimed to evaluate the reproduction status of snakehead in concrete tank  and in natural swamp aquatic. Seven indicators can be made by knowing the snakehead status indicator reproduction so that breeding manipulation in concrete tank can be done. The seven indicators were gonadosomatic indexs, hevatosomatic indexs, body weight, liver weight, gonade weight, egg diameter, fecundity and estradiol-17β concentrations. Result measurement of the gonadosomatic indexs of the snakehead in natural swamp aquatic show in Agust month was 3,3 ± 0.09 and hevatosomatic indexs was 1,1 ± 0.05 in Agust month. For gonadosomatic indexs and  hevatosomatic indexs in concrete tank in April month was 3.6 ± 0.09 and Januari month was 1.0 ± 0.08, respectively. Result of measurement the fecundity and egg diameter of the snakehead in concrete tank in Pebruary month was 2978.3 ± 7.64 and 1.3 ± 0.00 mm respectively, The fecundity and egg diameter of the snakehead in natural swamp aquatic in Januari month was 3080.0 ± 7.91 and Nopember and December was 1.5 ± 0.04 mm respectively. The estradiol-17β concentration of the snakehead in swamp aquatic show the higest concentration in natural aquatic. Average concentration estradiol-17β in natural aquatic in Juni month was 85.3 ± 9.37 pg/ml until December was 169.2 ± 6.22 pg/ml. In concrete tank from 80.5 ± 5.17 pg/ml in Juli until  118.3 ± 6.78 pg/ml in April. In general it is concluded that the reproduction status of snakehead was similar  between in concrete tank and natural swamp aquatic. Enviroment ”trigger” was the limited factor in finally gonade maturation.

  19. Biochemical modulation in male specimens of Channa punctatus ...

    African Journals Online (AJOL)

    admin

    Biochemical modulation in male specimens of Channa punctatus (Bloch) under different habitats and seasons. C. P. Singh1, R. N. Ram2, Mohd. Danish2* and .... were analyzed using titrimetric method. (APHA, 1992) and temperature, pH, total dissolved solids and conductivity were measured using electronic digital meter.

  20. Marc bloch

    OpenAIRE

    Restrepo A., Luis Antonio

    2011-01-01

    Lucien Fevre (1878-1956) y Marc Bloch ( 1866-1944), se conocieron cuando fueron profesores de la Universidad de Estrasburgo, mientras escribían y publicaban algunos de sus primeros grandes libros, por ejemplo, Los reyes taumaturgos de Bloch en 1924, Martin Lutero.

  1. The complete mitochondrial genome of Channa marulius (Perciformes: Channidae: Channa).

    Science.gov (United States)

    Cui, Jun; Lashari, Punhal; Zhang, Songhao; Wang, Kai; Xu, Jian; Laghari, Muhammad Younis; Mahboob, Shahid; Al-Ghanim, Khalid A; Zhang, Yan; Xu, Peng

    2016-01-01

    The traditional polymerase chain reaction method was employed to obtain the complete mitochondrial genome of Channa marulius from Pakistan. The mitogenome was determined to be 16,569 bp in length. It contains 13 protein-coding genes, 2 rRNAs and 22 tRNAs. This is the first report on the complete mitogenome sequence of C. marulius.

  2. Phenolic compounds from Bletilla striata.

    Science.gov (United States)

    Wang, Li-Ning; He, Yong-Zhi; Zhao, Qi-Duo; Deng, Yan-Ru; Wu, Pei-Qian; Zhang, Yan-Jun

    2017-10-01

    Two new malic acid derivatives, namely eucomic acid 1-methyl ester (2) and 6'''-acetylmilitaline (7), together with ten known compounds (1, 3-6, 8-12), were isolated from the dry tubers of Bletilla striata (Thunb.) Reichb. F., a perennial traditional Chinese medicinal herb, which was used for the treatment of pneumonophthisis, pneumonorrhagia, tuberculosis, and hemorrhage of the stomach or lung. Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR, and HR-ESI-MS.

  3. Recovery And Valorization Of Snakehead Fish Channa Striata Surimi Wash Water As Stock Albumin Tablet

    Directory of Open Access Journals (Sweden)

    Ikbal Syukroni

    2017-11-01

    Full Text Available Surimi washing process is aimed to concentrate the myofibril protein by removing catepsin enzyme fat pigment blood and sarcoplasmic protein which is soluble in wash water. The soluble subtances cause trouble environment if it was untreated. In addition recovery protein will give benefit both in reducing trouble environment and utilizing soluble protein as sources of albumin protein. The objectives of research were to recover albumin from snakehead fish surimi wash water and to valorize as stock albumin tablet. Recovery of albumin use 0.05 m ultrafiltration membrane and the valorization of albumin tablets was by direct compression. The protein band with molecular weight of 67.741 kDa on the retentate was detected as albumin. Concentration of protein recover by ultrafiltration membrane increased 89.98 and the albumin content 3.50.4 gdl. Based on the result of chemical composition and microbiology analysis albumin of snakehead surimi wash water appropriate with Indonesia National Standard SNI quality requirement about snakehead fish albumin extract. The best formulation in the preparation of surimi wash water albumin tablet was by using corn starch excipients with uniformity weight value 410.39 0.09 g hardness value 7.65 0.8 Kp uniformity size of tablet with diameter 1 cm and thickness 0.59 cm friability value 2.3 and disintregation time of the tablet is 2 minutes 16 second.

  4. Osteopathia striata with cranial sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Gay, B.B. [Emory Univ., Atlanta, GA (United States). Dept. of Radiology; Elsas, L.J. [Emory Univ., Atlanta, GA (United States). Dept. of Pediatrics; Wyly, J.B. [Emory Univ., Atlanta, GA (United States). Dept. of Radiology; Pasquali, M. [Emory Univ., Atlanta, GA (United States). Dept. of Pediatrics

    1994-03-01

    Osteopathia striata with cranial sclerosis (OS-CS) is a specific bone dysplasia manifested by hypertelorism, flat nasal bridge, frontal bossing, large head, hypoplastic maxilla, palate anomalies, chronic otitis media, hearing deficits, nasal obstruction, and neurological changes of deafness, facial palsy, ophthalmoplegia, and mental retardation. We will review the clinical and radiologic findings in a new patient from birth to 20 years; this is believed to be the thirty-fifth patient reported. OS-CS is 2.5 times more common in females and occurs as an autosomal dominant condition or a sporadic dominant mutation with patients presenting for evaluation from the newborn period to the fifth decade. Skeletal abnormalities are distinctive including sclerosis of the skull base and calvarium, linear striated densities in the long bones and pelvis, and poor development of the mastoid and sinus air cells. Radionuclide bone scans with SPECT indicated in our patient increased bone turnover which was supported by biochemical findings of increased pyridinoline excretion. The major complications are due to constriction of essential foramina at the skull base. The condition is not life-threatening but can produce disability. (orig.)

  5. Bloch — Sulzberger syndrome

    Directory of Open Access Journals (Sweden)

    Slesarenko N.A.

    2015-09-01

    Full Text Available Five clinical observations in pediatric patients with Bloch — Sulzberger syndrome are presented. The observation had been performed for six months. The differential diagnosis depending on the stage of the disease was done. The article contains variants of treating patients of this category.

  6. Mycobacterial infection in Northern snakehead (Channa argus) from the Potomac River catchment

    Science.gov (United States)

    Densmore, Christine L.; Iwanowicz, L.R.; Henderson, A.P.; Iwanowicz, D.D.; Odenkirk, J.S.

    2016-01-01

    The Northern snakehead, Channa argus (Cantor), is a non-native predatory fish that has become established regionally in some temperate freshwater habitats within the United States. Over the past decade, Northern snakehead populations have developed within aquatic ecosystems throughout the eastern USA, including the Potomac River system within Virginia, Maryland and Washington, D.C. Since this species was initially observed in this region in 2002, the population has expanded considerably (Odenkirk & Owens 2007). In the Chesapeake Bay watershed, populations of Northern snakehead exist in the lower Potomac River and Rappahannock Rivers on the Western shore of the Bay, and these fish have also been found in middle or upper reaches of river systems on the Eastern shore of the Bay, including the Nanticoke and Wicomico Rivers among others. Over the past several years, many aspects of Northern snakehead life history in the Potomac River have been described, including range and dispersal patterns, microhabitat selection and diet (Lapointe, Thorson & Angermeier 2010; Saylor, Lapointe & Angermeier 2012; Lapointe, Odenkirk & Angermeier 2013). However, comparatively little is known about their health status including susceptibility to parasitism and disease and their capacity to serve as reservoirs of disease for native wildlife. Although considered hardy by fisheries biologists, snakehead fish have demonstrated susceptibility to a number of described piscine diseases within their native range and habitat in Asia. Reported pathogens of significance in snakehead species in Asia include snakehead rhabdovirus (Lio-Po et al. 2000), aeromonad bacteria (Zheng, Cao & Yang 2012), Nocardia (Wang et al. 2007) andMycobacterium spp. (Chinabut, Limsuwan & Chantatchakool 1990; ). Mycobacterial isolates recovered from another snakehead species (Channa striata) in the previous studies have included M. marinum and M. fortuitum, as identified through molecular

  7. DISTRIBUSI NITROGEN DAN FOSFOR PADA BUDIDAYA IKAN GABUS (Channa striata DENGAN APLIKASI ECENG GONDOK (Eichhornia crassipes DAN PROBIOTIK

    Directory of Open Access Journals (Sweden)

    Adang Saputra

    2018-01-01

    Full Text Available Permasalahan yang dihadapi pembudidaya ikan dengan sistem intensif adalah meningkatnya limbah yang terakumulasi pada air dan sedimen. Limbah budidaya ikan pada umumnya berupa padatan dan nutrien terlarut pada air terutama nitrogen dan fosfor. Tujuan penelitian ini adalah mengkaji distribusi nitrogen total dan fosfor total pada budidaya ikan gabus secara intensif yang diberi eceng gondok Eichhornia crassipes dan probiotik (Pseudomonas aeruginosa dan Achromobacter insuavis. Penelitian dirancang menggunakan rancangan acak lengkap dengan perlakuan pemberian kombinasi eceng gondok dan probiotik (A, pemberian eceng gondok (B, dan pemberian probiotik (C, masing-masing perlakuan diulang tiga kali. Benih ikan gabus yang digunakan berukuran panjang 14,74 ± 0,01 cm dan bobot 25,53 ± 0,09 g dengan padat tebar 175 ekor/kolam (50 ekor/m3. Selama 90 hari masa pemeliharaan, ikan gabus diberi pakan berupa pelet dengan kandungan protein sekitar 30%. Jumlah pemberian pakan 5% dari biomassa dengan frekuensi pemberian empat kali dalam sehari (pagi, siang, sore, dan malam. Hasil penelitian menunjukkan nitrogen dan fosfor pada budidaya ikan gabus terdistribusi pada eceng gondok, sedimen, air, dan ikan. Eceng gondok menyerap nitrogen dan fosfor paling tinggi (P<0,05 dibandingkan air, ikan, dan sedimen. Laju pertumbuhan spesifik bobot (4,37 ± 0,01%/hari dan biomassa (1,88 ± 0,01 g ikan gabus tertinggi dicapai pada pemberian kombinasi eceng gondok dan probiotik. Hasil ini dapat dijadikan landasan untuk pengelolaan limbah nitrogen dan fosfor pada budidaya ikan gabus secara intensif. One of the problems in intensive aquaculture system is the the accumulation of waste in the water and sediment. Aquaculture wastes are discharged into the water in form of solids and dissolved nutrients which mostly consisted of nitrogen and phosphorus. The purpose of this study was to study the dynamics of total nitrogen and phosphorus in an intensive aquaculture media supplied with water hyacinth and probiotics (Pseudomonas aeruginosa and Achromobacter insuavis. The study was designed using a completely randomized design with treatment combinations of water hyacinth with probiotic (A, water hyacinth (B, and probiotic (C. Each treatment consisted of three replications. The seeds of snakehead used had body length of 14.74 ± 0.01 cm and weight 25.53 ± 0.09 g, stocked in ponds with stocking density of 175 individuals/pond (50 individuals/m3. During 90 days of rearing, the fish were fed with pellet with protein content of 30%. The amount of feeding was 5% of the biomass with feeding frequency of four times a day (morning, afternoon, evening, and night. The results showed that the produced nitrogen and phosphorus in the snakehead cultivation were distributed to water hyacinth, sediment, water, and fish. Water hyacinth absorbed most of the nitrogen and phosphorus compared to water, fish, and sediment. Higher specific growth rate (4.37 ± 0.01%/day and biomass (1.88 ± 0.01 g of snakehead were achieved in combination of water hyacinth and probiotic treatment. These results can be used as a basis for the management of nitrogen and phosphorus wastes in an intensive fish farming.

  8. Extract of haruan (Channa striata extract increasing reepithelialisation count in wound healing process on wistar rat’s buccal mucosa

    Directory of Open Access Journals (Sweden)

    Devintha Ayu Mellyana Tamales

    2016-04-01

    Full Text Available Haruan is Kalimantan’s indigenous fish which has the potency to accelerate wound healing. Haruan extract has substantial properties such as albumin, Zn, Cu, and Fe to accelerate wound healing. The aim of this study was to examine the effect of haruan extract on reepithelialization of wistar rats’ buccal mucosa wound healing on day 3, 5, 7, and 10 histopathologically. This study was true experimental with posttest with control design. Samples were divided in 16 treatment groups, haruan extract 25%, 50%, 100% treatment groups and aquadest treatment group as negative control, each treatment was performed for 10 days. Epithelial thickness count reached its peak on day 10. Mean epithelial thickness scoring of each group was 50.40 µm; 56.85 µm; 62.81 µm; 38.28 µm respectively. Two way Anova and Post Hoc LSD tests presented there was a significant difference between negative control and haruan extract groups. Haruan extract treatment significantly increases epithelial thickness count in wound healing process.

  9. INTERVENSI FOLICLE STIMULATING HORMONE (FSH DALAM PROSES REMATURASI INDUK IKAN GABUS HARUAN Channa Striata Blkr DIDALAM WADAH BUDIDAYA

    Directory of Open Access Journals (Sweden)

    Akhmad Ridha Fani

    2016-06-01

    Full Text Available Snakehead and other fish species in waters of the swamp doing spawning at the beginning or in the middle of the rainy season. Gonadal maturation process so as to return time is limited. Aquaculture development is highly dependent on the availability of seeds that meet the timeliness, quality and quantity. The seeds can be produced continuously if supported by the availability of mature broodstock with good quality eggs. Some research about the role of hormones and or the use of stimulants to the success in support of gonad development and spawning, such as; Siam Jambal fish, Pangasius hypophthalmus (Ernawati 1999, Catfish, Clarias batrachus (Zairin et al. 2001, and catfish, Hemibagrus nemurus (Supriyadi 2005. By because they were with potential memamfaatkan folicle Stimulating Hormone (FSH that serves as the control at the start of the reproductive cycle up to ovulation and spermiasi in fish. The aim of this study was to determine the effect of the injection folicle Stimulating Hormone (FSH in the parent rematurisasi catfish. Results from the start 17007-52327 item, 0,63-1,07mm egg diameter, IGS range of 4, 13 to 8.50%, and ranged from 0.86 2.4% IHS. Based on the results of the study injection folicle Stimulating Hormone (FSH capable mepersingkat rematurasi processing time.

  10. Haematological and ion regulatory effects of nitrite in the air-breathing snakehead fish Channa striata

    DEFF Research Database (Denmark)

    Lefevre, Sjannie; Jensen, Frank Bo; Huong, Do T.T.

    2012-01-01

    M. Effects of sub-lethal exposures to nitrite (0 mM, 1.4 mM, and 3.0 mM) were determined during a 7-day exposure period. Plasma nitrite increased, but the internal concentration remained well below ambient levels. Extracellular nitrate rose by several mM, indicating that a large proportion of the nitrite...... taken up was converted to nitrate. Nitrite reacted with erythrocyte haemoglobin (Hb) causing methaemoglobin (metHb) to increase to 30% and nitrosylhaemoglobin (HbNO) to increase to 10% of total Hb. Both metHb and HbNO stabilised after 4 days, and functional Hb levels accordingly never fell below 60......% of total Hb. Haematocrit and total Hb were unaffected by nitrite. Although the effects of nitrite exposure seemed minor in terms of plasma nitrite and metHb increases, ion balance was strongly affected. In the high exposure group, total osmolality decreased from 320 mOsm to 260 mOsm, and plasma sodium from...

  11. Salinity and survival of Martesia striata (Linn) in Cochin harbour

    OpenAIRE

    Cheriyan, P.V.; Cherian, C.J.

    1980-01-01

    The effects of salinity variations on the survival of Martesia striata from Cochin harbour are presented. It is observed that at least a few of the animals survive the low saline conditions during monsoon. Laboratory experiments showed the lethal salinity as 6‰ when animals acclimatised in 34‰ were subjected to abrupt changes in salinity. But acclimatisation to 17‰ salinity showed a downward shift in the lethal salinity to 4‰. The present observations indicate that M. striata is euryhaline ar...

  12. A theory of generalized Bloch oscillations

    DEFF Research Database (Denmark)

    Duggen, Lars; Lew Yan Voon, L. C.; Lassen, Benny

    2016-01-01

    Bloch oscillations of electrons are shown to occur for cases when the energy spectrum does not consist of the traditional evenly-spaced ladders and the potential gradient does not result from an external electric field. A theory of such generalized Bloch oscillations is presented and an exact cal...... oscillations. We stipulate that the presented theory of generalized Bloch oscillations can be extended to other systems such as acoustics and photonics.......Bloch oscillations of electrons are shown to occur for cases when the energy spectrum does not consist of the traditional evenly-spaced ladders and the potential gradient does not result from an external electric field. A theory of such generalized Bloch oscillations is presented and an exact...... calculation is given to confirm this phenomenon. Our results allow for a greater freedom of design for experimentally observing Bloch oscillations. For strongly coupled oscillator systems displaying Bloch oscillations, it is further demonstrated that reordering of oscillators leads to destruction of Bloch...

  13. Marc Bloch y el compromiso del intelectual

    Directory of Open Access Journals (Sweden)

    Carlos Antonio Aguirre Rojas

    2004-07-01

    Full Text Available Herewith is discussed Marc Bloch's work as well as his political engagement by presenting his intellectual formation and his contribution to 20 th Century historiography. We enhance the genesis of Bloch's historical work by his approach to Emile Durkheim's and Henri Berr's thought. It is also analysed Bloch's resistance against Nazism and his brutal assassination.

  14. Osteopathia striata: a characteristic X-ray finding in focal dermal hypoplasia (Goltz-Gorlin syndrome)

    Energy Technology Data Exchange (ETDEWEB)

    Barthels, W.; Boepple, D.; Petzel, H.

    1982-12-01

    Two cases of the very rare Goltz-Gorlin syndrome are presented. The relationship of osteopathia striata and focal dermal hypoplasia is discussed, and it is concluded that the osteopathia striata represents the characteristic picture of this ectopic mesodermal abnormality.

  15. Felix Bloch (1905–1983)

    Indian Academy of Sciences (India)

    IAS Admin

    His doctoral thesis (1928) established the quantum theory of solids, using Bloch waves. Soon after, with Grueneisen, he gave the first comprehensive theory of the temperature dependent resistivity of metals, deriving a formula named after both of them. The transition separating two magnetic domains with different ...

  16. Bletilla striata: Medicinal uses, phytochemistry and pharmacological activities.

    Science.gov (United States)

    He, Xirui; Wang, Xiaoxiao; Fang, Jiacheng; Zhao, Zefeng; Huang, Linhong; Guo, Hao; Zheng, Xiaohui

    2017-01-04

    Bletilla striata (Thunb.) Reichb. f. (Orchidaceae), also known as Hyacinth Orchid and Baiji (Simplified Chinese: ), not only has been widely used for the treatment of hematemesis, hemoptysis, and traumatic bleeding due to the efficacy of arresting bleeding with astringent action, but also has been applied topically to overcome ulcers, sores, swellings, and chapped skin due to the efficacy of dispersing swelling and promoting tissue regeneration. Additional medical applications include the treatment of tuberculosis, malignant ulcers, hemorrhoids, anthrax, eye diseases, and silicosis. This review aims to provide up-to-date information on the botanical characterization, medicinal uses, chemical constituents, pharmacological activities, and toxicity of B. striata. In addition, this paper also focuses on the possible exploitation of this plant for the treatment of different diseases, and uncovers opportunities for future research. The relevant information on B. striata was gathered from worldwide accepted scientific databases via an electronic search (Google Scholar, Web of Science, ScienceDirect, ACS Publications, PubMed, Wiley Online Library, SciFinder, CNKI). Information was also obtained from The Plant List, Chinese pharmacopoeia, Chinese herbal classics books, PhD and MSc dissertations, etc. A comprehensive analysis of the literature obtained through the above-mentioned sources confirmed that the ethnomedical usages of B. striata have been recorded in Mongolia, Korea, Japan, and China. Phytochemical investigations revealed that the major chemical constituents of B. striata are polysaccharides, bibenzyls, phenanthrenes, triterpenoids and its saponins, steroids and its saponins, which also have been proven to be the main bioactive substances capable of exhibiting numerous pharmacological activities including wound healing, antiulcer, hemostasis, cytotoxicity, antimicrobial, anti-inflammation, anti-oxidation, immunomodulation, anti-fibrosis, antiaging, anti

  17. Osteosarcoma arising in a femur with melorheostosis and osteopathia striata

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, D.D.; Bruzzi, J.F.; Eustace, S. [Department of Radiology, Mater Misericordiae Hospital, Eccles Street, Dublin 7 (Ireland); Thakore, H.; O' Keane, J.C. [Department of Pathology, Mater Misericordiae Hospital, Dublin (Ireland)

    2002-08-01

    Osteopathia striata is an asymptomatic autosomal dominant or sporadically inherited disorder that causes dense striations at sites of endochondral bone formation, with a predilection for the metaphyses of long bones. Melorheostosis is a mixed sclerosing dysplasia with disturbance of both endochondral and intramembranous ossification, in which disordered intramembranous ossification dominates. It presents typical radiological changes of cortical hyperostosis distributed along a sclerotome with variable associated cutaneous and clinical features. Overlap syndromes including one or more of these diseases are described. We report a 44-year-old man with both melorheostosis and osteopathia striata who presented with pain secondary to superimposed osteosarcoma. In reporting this case we discuss the relationship between sclerosing dysplasia and either coexisting or complicating sarcoma. (orig.)

  18. First Bloch eigenvalue in high contrast media

    Energy Technology Data Exchange (ETDEWEB)

    Briane, Marc, E-mail: mbriane@insa-rennes.fr [Institut de Recherche Mathématique de Rennes, INSA de Rennes (France); Vanninathan, Muthusamy, E-mail: vanni@math.tifrbng.res.in [TIFR-CAM, Bangalore (India)

    2014-01-15

    This paper deals with the asymptotic behavior of the first Bloch eigenvalue in a heterogeneous medium with a high contrast εY-periodic conductivity. When the conductivity is bounded in L{sup 1} and the constant of the Poincaré-Wirtinger weighted by the conductivity is very small with respect to ε{sup −2}, the first Bloch eigenvalue converges as ε → 0 to a limit which preserves the second-order expansion with respect to the Bloch parameter. In dimension two the expansion of the limit can be improved until the fourth-order under the same hypotheses. On the contrary, in dimension three a fibers reinforced medium combined with a L{sup 1}-unbounded conductivity leads us to a discontinuity of the limit first Bloch eigenvalue as the Bloch parameter tends to zero but remains not orthogonal to the direction of the fibers. Therefore, the high contrast conductivity of the microstructure induces an anomalous effect, since for a given low-contrast conductivity the first Bloch eigenvalue is known to be analytic with respect to the Bloch parameter around zero.

  19. A New Essential Norm Estimate of Composition Operators from Weighted Bloch Space into -Bloch Spaces

    Directory of Open Access Journals (Sweden)

    René E. Castillo

    2013-01-01

    Full Text Available Let be any weight function defined on the unit disk and let be an analytic self-map of . In the present paper, we show that the essential norm of composition operator mapping from the weighted Bloch space to -Bloch space is comparable to where for ,   is a certain special function in the weighted Bloch space. As a consequence of our estimate, we extend the results about the compactness of composition operators due to Tjani (2003.

  20. Claude Bloch scientific works, oeuvre scientifique

    CERN Document Server

    Bloch, Claude; De Dominicis, Cyrano; Gillet, Vincent; Messiah, Albert

    1975-01-01

    Claude Bloch: Scientific Works Oeuvre Scientifique covers the collection of scientific works of Claude Bloch. The book includes topics on field theories with non-localized interaction and notes on the symmetry properties of nuclear wave functions. It also covers theory of nuclear level density; the theory of imperfect fermi gases; the structure of nuclear matter; and the canonical form of an antisymmetric tensor and its application to the theory of superconductivity.

  1. Biocompatibility of Bletilla striata Microspheres as a Novel Embolic Agent

    Directory of Open Access Journals (Sweden)

    ShiHua Luo

    2015-01-01

    Full Text Available We have prepared Chinese traditional herb Bletilla striata into microspheres as a novel embolic agent for decades. The aim of this study was to evaluate the biocompatibility of Bletilla striata microspheres (BSMs. After a thermal test of BSMs in vitro, the cell biocompatibility of BSMs was investigated in mouse fibroblasts and human umbilical vein endothelial cells using the methyl tetrazolium (MTT assay. In addition, blood biocompatibility was evaluated. In vivo intramuscular implantation and renal artery embolization in rabbits with BSMs were used to examine the inflammatory response. The experimental rabbits did not develop any fever symptoms after injection of BSMs, and BSMs exhibited no cytotoxicity in cultured mouse fibroblasts and human umbilical vein endothelial cells. Additionally, BSMs exhibited high compatibility with red blood cells and no hemolysis activity. Intramuscular implantation with BSMs resulted in a gradually lessened mild inflammatory reaction that disappeared after eight weeks. The occlusion of small renal vessels was associated with a mild perivascular inflammatory reaction without significant renal and liver function damage. In conclusion, we believe that BSMs exhibit high biocompatibility and are a promising embolic agent.

  2. Complete sequence and characterization of mitochondrial DNA genome of Channa asiatica (Perciformes: Channidae).

    Science.gov (United States)

    Meng, Yan; Zhang, Yan

    2016-01-01

    The complete nucleotide sequence of Channa asiatica mitochondrial (mtDNA) genome was determined in this study. The genome sequence (GenBank accession number KJ930190) was 16,550 base pairs in length, and the gene content and organization on the mitochondrial genome were similar to the other Channa fishes. The overall base composition of C. asiatica mitogenome is 29.4% A, 26.3% T, 15.3% G, 29.0% C, with a high A + T content of 55.7%. The mitochondrial sequence could provide useful genetic information for studying the molecular identification, population genetics, phylogenetic analysis and conservation genetics.

  3. Ecology of the wood-boring bivalve Martesia striata (Pholadidae) in Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    Yennawar, P.L.; Thakur, N.L.; Anil, A.C.; Venkat, K.; Wagh, A.B.

    Martesia striata is one of the dominant wood-boring organisms found in Indian waters. Incidence of this organism in the Zuari estuary (Goa) was evaluated by exposing wooden panels (Mangifera indica) to the marine environment between January 1996...

  4. The Ising-Bloch transition in degenerate optical parametric oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Arjona, Isabel [Departament d' Optica, Universitat de Valencia, Dr Moliner 50, 46100 Burjassot (Spain); Silva, Fernando [Departament d' Optica, Universitat de Valencia, Dr Moliner 50, 46100 Burjassot (Spain); Valcarcel, German J de [Departament d' Optica, Universitat de Valencia, Dr Moliner 50, 46100 Burjassot (Spain); Roldan, Eugenio [Departament d' Optica, Universitat de Valencia, Dr Moliner 50, 46100 Burjassot (Spain); Sanchez-Morcillo, VIctor J [Departament de FIsica Aplicada, Universitat Politecnica de Valencia, Carretera Nazaret-Oliva S/N, 46730 Grao de Gandia (Spain)

    2004-05-01

    Domain walls in type I degenerate optical parametric oscillators are numerically investigated. Both steady Ising and moving Bloch walls are found, bifurcating one into another through a nonequilibrium Ising-Bloch transition. Bloch walls are found that connect either homogeneous or roll planforms. Secondary bifurcations affecting Bloch wall movement are characterized that lead to a transition from a steady drift state to a temporal chaotic movement as the system is moved far from the primary Ising-Bloch bifurcation. Two kinds of routes to chaos are found, both involving tori: the usual Ruelle-Takens and an intermittent scenario.

  5. Bloch-Messiah theorem at finite temperature

    Science.gov (United States)

    Tanabe, K.; Sugawara-Tanabe, K.

    1991-03-01

    The Bloch-Messiah theorem is extended to the thermal Hartree-Fock-Bogoliubov (THFB) theory by making use of the thermo field dynamics. This enables us to define the correct order parameter describing the superconducting phase at finite temperature, and demonstrates consistency of the THFB formalism.

  6. The occurrence of Glyceria striata (Lam. Hitchc. in Europe and the new localities of the species in Poland

    Directory of Open Access Journals (Sweden)

    Bartosz Piwowarski

    2012-06-01

    Full Text Available Glyceria striata (Lam. Hitchc. is a North American species that has been recorded in most, semi-natural habitats in Europe, e.g. in meadows, bog springs, margins of water bodies. It is circumscribed within two taxa of lower rank: G. striata subsp. striata and G. striata subsp. stricta. Only G. striata subsp. stricta has been reported from Europe. This paper gives a list of the European locali- ties of the species (48 and describes two newly discovered localities in Poland (the Wyżyna Małopolska upland and the Western Carpathian Mts.. The distribution of G. striata in Europe is mapped and potential migration routes of the species are discussed.

  7. Salutary value of haruan, the striped snakehead Channa striatus – a review

    Directory of Open Access Journals (Sweden)

    Mohammed Abdul Kader Haniffa

    2014-05-01

    Full Text Available Murrel namely Channa striatus or haruan contains all essential elements to maintain good health and to recover the lost energy after prolonged illness. The fatty acid composition (% of total fatty acid indicated the abundant presence of C16:0 fatty acid as 30% and the other major fatty acids were C22:6 (15%, C20:4 (19%, C18:1 (12% and C18:0 (15%. Haruan contains arachidonic acid (C20:4 as 19.0%, a precursor for prostaglandin and thromboxane biosyntheses. Both fatty and amino acids are important components for wound healing processes. Both the fillet and mucus extracts of haruan were found to exhibit a concentration dependent antinociceptive activity. In vitro antioxidant activity was higher in Channa roe protein hydrolysate than in Labeo roe protein hydrolysate in both DPPH radical scavenging and ferric reducing power. Protein content of roe concentrates (RPC was found to be 90.2% (Channa and 82.5% (Lates. Water absorption, oil absorption, foam capacity, stability and emulsifying capacity were found to be higher in Channa RPC than in Lates RPC. Characterization of protein hydrolysates from muscle and myofibrillar samples of haruan showed different kinetic and proteolytic activities. The skin extract of haruan influences the serotonergic receptor system thus they can function as an anti-depressant. Thus, haruan is the best example for food as medicine.

  8. Quantum state transfer via Bloch oscillations

    Science.gov (United States)

    Tamascelli, Dario; Olivares, Stefano; Rossotti, Stefano; Osellame, Roberto; Paris, Matteo G. A.

    2016-01-01

    The realization of reliable quantum channels, able to transfer a quantum state with high fidelity, is a fundamental step in the construction of scalable quantum devices. In this paper we describe a transmission scheme based on the genuinely quantum effect known as Bloch oscillations. The proposed protocol makes it possible to carry a quantum state over different distances with a minimal engineering of the transmission medium and can be implemented and verified on current quantum technology hardware. PMID:27189630

  9. Taking a peek at Bloch oscillations

    Science.gov (United States)

    Morsch, Oliver

    2016-11-01

    Bloch oscillations arise when matter waves inside a periodic potential, such as a crystal lattice, are accelerated by a constant force. Keßler et al (2016 New J. Phys. 18 102001) have now experimentally tested a method that allows one to observe those oscillations continuously, without a destructive measurement on the matter wave. Their approach could help to make cold atom-based accelerometers and gravimeters more precise.

  10. On Rabi oscillations between Bloch bands

    OpenAIRE

    Plötz, Patrick

    2010-01-01

    We study Rabi oscillations between the bands of an arbitrary biased superlattice in a tight-binding model. We reduce the problem to an equation of Whittaker--Hill type and, in absence of any known solutions in closed form, discuss different approximations to describe the oscillations between the Bloch bands. We identify regimes of weak and strong inter-band coupling and compare predictions for these Rabi oscillations to numerical results.

  11. Theory of Magnetization in Bloch Electron Systems

    Science.gov (United States)

    Ogata, Masao

    2017-04-01

    The exact formulas for magnetization and magnetic susceptibility are derived for Bloch electrons in terms of Bloch wave functions. They are extensions of the previous work to general cases where the spin-orbit interaction as well as the Zeeman term is included, the potential is noncentrosymmetric, and the time-reversal symmetry is broken. The obtained magnetization for Bloch electrons is a natural generalization of the free-electron magnetic moment including the effect of the spin-orbit interaction. The obtained susceptibility has six contributions and the physical meaning of each term is clarified. The new formula contains the Landau-Peierls, Pauli, and Van Vleck susceptibilities, the atomic diamagnetism, and contributions from the "Berry curvature". In the atomic limit, the obtained formula reduces to two contributions: the atomic diamagnetism and a generalized form of the Van Vleck susceptibility modified by the spin-orbit interaction. It is also found that, in general cases, the Pauli, Van Vleck (interband), and Berry curvature susceptibilities are closely related to common magnetization matrix elements, which is in sharp contrast to previous studies. A general form of the off-diagonal magnetic susceptibility is also derived.

  12. The Striated Parachute Spider Poecilotheria striata Pocock, 1895 (Araneae: Theraphosidae: a note on taxonomy, distribution and conservation status

    Directory of Open Access Journals (Sweden)

    M. Siliwal

    2013-08-01

    Full Text Available The known distribution range of Poecilotheria striata Pocock, 1895 in India is from Mysuru in the north to Thiruvananthapuram in the south. During the recent surveys in northern Karnataka, P. striata was recorded from six locations in Dandeli and nearby areas in the Uttara Kannada District. With the new records from Uttara Kannada, the distribution range of this species extends to the northern part of the Western Ghats by ca. 400km from Mysuru. Additional records on distribution of P. striata are also provided from various surveys carried out in the last 10 years. Based on these new records, the IUCN Red List status of P. striata is recommended to be reassessed as Near Threatened. Additional information on the morphology and natural history of P. striata is provided in the paper.

  13. Magnetic confinement of repelling Bloch walls

    Science.gov (United States)

    Magyari, E.; Thomas, H.

    1992-01-01

    In a ferromagnet with orthorhombic magneto-crystalline anisotropy, two repelling 180° domain walls (π kinks) can be pushed together to form a 360° domain wall (2π kink) by applying a magnetic field in the easy direction. We show that such a magnetically confined static 360° plane domain wall with Bloch-like structure, connecting two semi-infinite domains with parallel spin orientation, is linearly stable only below a critical strength Bc of the applied field. At B = Bc it becomes unstable with respect to a mode with spin component along the hard direction.

  14. On history and salvation in Emmanuel Levinas and Ernst Bloch

    African Journals Online (AJOL)

    p1243322

    clearly noticeable in what Bloch claims with respect to Goethe. “Goethe … imagined not only the cosmic survival of his essence but precisely also immortality in his work which had become historical and which would remain behind as historical” (PH 1163, italics added). Bloch's texts, however, provides also for the possibility ...

  15. SOME SOLITON PROPERTIES OF COLLIDING VERTICAL BLOCH LINES

    OpenAIRE

    Sukiennicki, A.; Kosiński, R.; Źebrowski, J.

    1988-01-01

    The collisions of two vertical Bloch lines are studied numerically. It is found that soliton like properties of the Bloch lines are obtained for a nonzero damping constant if the power input is large enough to balance the effect of dissipation.

  16. Breeding Behavior and Parental Care of the Induced Bred Striped Murrel Channa striatus Under Captive Conditions

    OpenAIRE

    Paray, Bilal Ahmad; M.A., Haniffa; D, Manikandaraja; Milton, M. James

    2014-01-01

    Spawning behaviour of artificially induced Indian snakehead Channa striatus in captivity was investigated using a Nikon Digital camera, D 40 and Videotape recordings. Following a routine hormone treatment technique for this fish, mature snakeheads were artificially induced by intramuscular injections Human Chorionic Gonodotrophin (HCG) at a dosage of 6000 IU kg−1 BW 24 h after the acclimatization terminated. In this experiment, three pairs of such hormone-treated matured snakeheads were intro...

  17. Proteomic analysis of the venom of the predatory ant Pachycondyla striata (Hymenoptera: Formicidae).

    Science.gov (United States)

    Santos, Pollyanna Pereira; Games, Patricia Dias; Azevedo, Dihego Oliveira; Barros, Edvaldo; de Oliveira, Leandro Licursi; de Oliveira Ramos, Humberto Josué; Baracat-Pereira, Maria Cristina; Serrão, José Eduardo

    2017-11-01

    The ants use their venom for predation, defense, and communication. The venom of these insects is rich in peptides and proteins, and compared with other animal venoms, ant venoms remain poorly explored. The objective of this study was to evaluate the protein content of the venom in the Ponerinae ant Pachycondyla striata. Venom samples were collected by manual gland reservoir dissection, and samples were submitted to two-dimensional gel electrophoresis and separation by ion-exchange and reverse-phase high-performance liquid chromatography followed by mass spectrometry using tanden matrix-assisted laser desorption/ionization with time-of-flight (MALDI-TOF/TOF) mass spectrometry and electrospray ionization-quadrupole with time-of-flight (ESI-Q/TOF) mass spectrometry for obtaining amino acid sequence. Spectra obtained were searched against the NCBInr and SwissProt database. Additional analysis was performed using PEAKS Studio 7.0 (Sequencing de novo). The venom of P. striata has a complex mixture of proteins from which 43 were identified. Within the identified proteins are classical venom proteins (phospholipase A, hyaluronidase, and aminopeptidase N), allergenic proteins (different venom allergens), and bioactive peptides (U10-ctenitoxin Pn1a). Venom allergens are among the most expressed proteins, suggesting that P. striata venom has high allergenic potential. This study discusses the possible functions of the proteins identified in the venom of P. striata. © 2017 Wiley Periodicals, Inc.

  18. Spin wave vortex from the scattering on Bloch point solitons

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho-Santos, V.L., E-mail: vagson.carvalho@usach.cl [Instituto Federal de Educação, Ciência e Tecnologia Baiano - Campus Senhor do Bonfim, Km 04 Estrada da Igara, 48970-000 Senhor do Bonfim, Bahia (Brazil); Departamento de Física, Universidad de Santiago de Chile and CEDENNA, Avda. Ecuador 3493, Santiago (Chile); Elías, R.G., E-mail: gabriel.elias@usach.cl [Departamento de Física, Universidad de Santiago de Chile and CEDENNA, Avda. Ecuador 3493, Santiago (Chile); Nunez, A.S., E-mail: alnunez@dfi.uchile.cl [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Casilla 487-3, Santiago (Chile)

    2015-12-15

    The interaction of a spin wave with a stationary Bloch point is studied. The topological non-trivial structure of the Bloch point manifests in the propagation of spin waves endowing them with a gauge potential that resembles the one associated with the interaction of a magnetic monopole and an electron. By pursuing this analogy, we are led to the conclusion that the scattering of spin waves and Bloch points is accompanied by the creation of a magnon vortex. Interference between such a vortex and a plane wave leads to dislocations in the interference pattern that can be measurable by means of magnon holography.

  19. Engineered surface Bloch waves in graphene-based hyperbolic metamaterials.

    Science.gov (United States)

    Xiang, Yuanjiang; Guo, Jun; Dai, Xiaoyu; Wen, Shuangchun; Tang, Dingyuan

    2014-02-10

    A kind of tunable hyperbolic metamaterial (HMM) based on the graphene-dielectric layered structure at near-infrared frequencies is presented, and the engineered surface Bloch waves between graphene-based HMM and isotropic medium are investigated. Our calculations demonstrate that the frequency and frequency range of surface Bloch waves existence can be tuned by varying the Fermi energy of graphene sheets via electrostatic biasing. Moreover, we show that the frequency range of surface Bloch waves existence can be broadened by decreasing the thickness of the dielectric in the graphene-dielectric layered structure or by increasing the layer number of graphene sheets.

  20. Slow light by Bloch surface wave tunneling.

    Science.gov (United States)

    Koju, Vijay; Robertson, William M

    2014-06-30

    We demonstrate a slow light configuration that makes use of Bloch Surface Waves as an intermediate excitation in a double-prism tunneling configuration. This method is simple compared to the more usual technique for slowing light using the phenomenon of electromagnetically induced transparency in atomic gases or doped ionic crystals operated at temperatures below 4 K. Using a semi-numerical approach, we show that a 1D photonic crystal, a multilayer structure composed of alternating layers of TiO(2) and SiO(2), can be used to slow down light by a factor of up to 400. The results also show that better control of the speed of light can be achieved by changing the number of bilayers and the air-gap thickness appropriately.

  1. Reexamination of Bloch-Messiah reduction

    Science.gov (United States)

    Cariolaro, Gianfranco; Pierobon, Gianfranco

    2016-06-01

    The Bloch-Messiah (BM) reduction allows the decomposition of an arbitrarily complicated Gaussian unitary into a very simple scheme in which linear optical components are separated from nonlinear ones. It is based on the combined application of the eigendecomposition (EID) and singular value decomposition (SVD) of the two matrices associated to the Bogoliubov transformation of the given Gaussian unitary, with the constraint that the unitary matrices appearing in the SVDs must verify a stringent condition, called in the paper "rotation condition". Thus, for a correct evaluation of the BM reduction, one has to choose, among the possible SVD pairs, the pair that meets this condition. The paper develops an approach to this problem, which is based on the introduction of a balancing matrix in the SVDs to fulfill the rotation condition. The theory is illustrated with a few application examples.

  2. Physiological maturity of ingazeiro Inga striata Benth. SeedsMaturação fisiológica de sementes de ingazeiro (Inga striata Benth

    Directory of Open Access Journals (Sweden)

    Marlene Feliciano Mata

    2013-05-01

    Full Text Available Inga striata Benth., Popularly known as ingazeiro, is a native fruit of tropical forests and riparian forests of the Amazon, Northeast and Minas Gerais. It is used in the reclamation of degraded areas and in rural and urban forestry. The objective of this study was to determine the most appropriate indices for assessing the maturity and ideal harvest seeds I. striata Benth. Trees I. striata were in swamp forest of altitude on Campus II of the Federal University of Paraíba (UFPB, Areia-PB. Assessments of seed maturation were performed in six seasons fruit harvests after anthesis (95, 110, 125, 140, 155 and 170 DAA and two consecutive years of observations (two seasons. The experimental design was completely randomized following a factorial 2 x 6 (two periods of observation and six seasons crop of fruit. At each harvest were evaluated dimensions of fruits and seeds, water content and dry weight of seeds and their germination and vigor (first germination, speed of germination, length and mass of the primary root and shoot. The seed physiological maturity was reached at 146 to 166 days after flowering in the first year and 155 days in the second year, in which periods had the lowest water content, maximum dry matter accumulation and germination; The size, content water, dry mass of seed germination and the dry weight of the aerial part of the seedling, were the best parameters that determined the physiological maturity of seeds of I. striata. Inga striata Benth. é uma arbórea nativa de ocorrência nas florestas tropicais e matas ciliares, distribui-se nas Antilhas, Sul da América tropical e Bolívia. No Brasil ocorre na Amazônia e região Nordeste até Minas Gerais, sendo utilizada na recuperação de solos de áreas degradadas, como frutífera e na arborização urbana. O objetivo do Inga striata Benth., popularmente conhecida como ingazeiro, é uma frutífera nativa das florestas tropicais e matas ciliares da Amazônia, Nordeste e Minas

  3. Sterculia striata seed kernel oil: Characterization and thermal stability

    Directory of Open Access Journals (Sweden)

    Oliveira Cavalheiro, José Marcelino

    2008-06-01

    Sterculia striata. Se determinaron la composición química, las propiedades químico-físicas, composición en ácidos grasos, así como la estabilidad térmica de la harina (polvo de almendra. La composición química de la harina contiene cerca de 25,8% de lípidos, los parámetros químico-físicos, tales como: índice de acidez, yodo, peróxido y saponificación fueron 0,82% (ácido oleico, 69,2 (g yodo/100 g de aceite, 4,20 m.eq./kg de aceite y 136,1 (mg KOH/g de aceite, respectivamente. Con relación a la composición en ácidos grasos, el aceite contiene 36,2; 43,7 y 10,9% de ácidos grasos saturados, monoinsaturados y polyinsaturados, respectivamente. El ácido palmítico (31,9%, oleico (41,7 y linoleico (10,73%, fueron los principales ácidos grasos saturados, monoinsaturados y polyinsaturados, respectivamente. Los ácidos grasos ciclopropenoides, esto es, ácidos estercúlico y malválico fueron identificados y cuantificados en la proporción de 5,3 y 2,3%, respectivamente. Con respecto a la estabilidad térmica del aceite, el análisis termogravimétrico (TGA demostró que el aceite es estable hasta la temperatura de 284 °C, a partir de este valor el aceite comenzó a perder masa. El análisis termogravimétrico diferencial (DTGA indicó la existencia de tres etapas de degradación con el aumento de la temperatura del aceite. Estas etapas significan la degradación de los aceites saturados, monoinsaturados y polyinsaturados. El análisis mediante calorimetría diferencial de barriido (DSC detectó dos zonas de transición de energía exotérmica, una debida a la reacción de oxidación y la otra a la descomposición de los ácidos grasos. La primera transición exotérmica del aceite comenzó a la temperatura (Ti de 287,79 °C con una variación de entalpía de 11,69 J/g y, la segunda con la temperatura inicial (Ti de 384,87 °C, una temperatura de pico (Tp 415,71 °C y una temperatura final (Tf de 448,9 °C con una variación de entalpía de 200,83 J/g.

  4. Growth and liver histology of Channa punctatus exposed to a common biofertilizer.

    Science.gov (United States)

    Nath, S; Matozzo, V; Bhandari, D; Faggio, C

    2018-01-28

    Mustard oil cake (MOC) is widely used as biofertilizer in the field of agriculture and aquaculture. Channa punctatus was exposed to 0.42 g.L -1 sublethal concentration for 4, 7, 14, 21 and 28 days. Due to such exposure, body growth and histological changes in liver were observed. It was revealed that weight, length and breadth of fish were gradually increased with the days of exposure in compare to control fish, whereas, liver showed an increase in sinusoidal space and lipidosis during early days, followed by a recovery from the stress of MOC on the 28th day.

  5. Age and growth patterns in Channa marulius from Harike Wetland (A Ramsar site), Punjab, India.

    Science.gov (United States)

    Dua, Anish; Kumar, Kanwaljit

    2006-05-01

    Scale samples of Channa marulius were collected and studied for age determination and calculation of growth parameters. The fish were sampled from Harike Wetland during 1998 to 1999. Linear relationship with a high degree of correlation was observed between total fish length and the lateral scale radius. Age determination studies revealed 5 age groups. The harvestable size falls just below the 2nd year. The regression equation is given. Various growth parameters indicate a hardy nature of the fish and the suitability of habitat ecology for its optimum growth.

  6. Isolasi dan Implementasi Protein Bioaktif Kepah (Atactodea striata Sebagai Bahan Obat Antibakteri

    Directory of Open Access Journals (Sweden)

    Tahirah Hasan

    2014-07-01

    Full Text Available This study aimed to 1 determine the degree of saturation of ammonium sulfate right to extract and purify the bioactive protein from shells (Atactodea striata, 2 determine the fraction of active protein from shells (Atactodea striata as a potential antibacterial. In this study used the Lowry method for determine protein concentration and agar diffusion method for antibacterial activity. Extraction of shells Atactodea striata was conducted by making use of buffer solution (0,1 M Tris-HCl of pH 8.3, 2 M NaCl, 0.01 M CaCl2, 1 % β-mercaptoethanol, and  0.5 % Triton X-100. Purification of proteins by  precipitation using ammonium sulfate at saturation level 30 %, 50 %, 70 %, and 90 %. The results showed that the protein concentration of the crude   extract is 41.6354 mg/mL. At fractionation rate of 0-90% saturation showed the highest concentration of protein found in fractions with 70% saturation level is 56.4184 mg/mL. The testing of antibacterial activity against Staphylococcus aureus showed that crude extracts and protein fractions Atactodea striata is considered effective as an antibacterial. The highest bioactivity during 24-hour incubation in protein fractions obtained by ammonium sulfate saturation level of 50% is 25.17 mm. Whereas the lowest activity was obtained at 90% saturation level is 14.05 mm. Bioactivity against Escherichia coli after incubation for 24 hours has the highest activity in the protein fraction with 30% ammonium sulfate saturation is 15.12 mm. Whereas the lowest activity was showed at 70% saturation level is 10.30 mm. After the observation was continued for 48 hours on both test bacteria, which formed a clear area becomes cloudy. It shows that the crude extract and fractions of protein tend to be bacteriostatic against Staphylococcus aureus and Escherichia coli.

  7. Division of labor in pachycondyla striata Fr. Smith, 1858 (Hymenoptera: Formicidae: Ponerinae)

    OpenAIRE

    Adolfo da Silva-Melo; Edilberto Giannotti

    2012-01-01

    Four colonies of the ant Pachycondyla striata were used to analyze the specie behavioral repertoire. Forty-six behavioral acts were recorded in laboratory. Here, we present the record the division of labor between the castes and the temporal polyethism of monomorphic workers. The queens carried out many of the behavioral traits recorded in this work however; they performed them less frequently compared to the worker. The workers activity involved chasing and feeding on fresh insects and using...

  8. Multiple queens in founding colonies of the neotropical ant Pachycondyla striata Smith (Formicidae: Ponerinae).

    Science.gov (United States)

    Rodrigues, M S; Vilela, E F; Azevedo, D O; Hora, R R

    2011-01-01

    In social insects, the typical mode of colony foundation occurs when a single queen is inseminated by a male and establishes a new colony, although we can find interspecific and intraspecific variations in queen number and queen-mating frequencies in a single colony. This study aimed to verify the queen number in Pachycondyla striata (Smith) colonies and to evaluate the level of aggressiveness among workers. We collected 14 colonies of P. striata. The behaviors of individuals from five multiple-queen colonies maintained in laboratory were studied by the method of scan sampling. In order to evaluate aggressiveness, dyadic encounters among heterocolonial and homocolonial workers were performed. The results showed that colonies of P. striata can have two or more mated queens (polygynous colonies) besides to monogynous ones (colony containing one queen). Because in polygynous colonies the number of workers was relatively low, such colonies could represent colonies in the foundation phase that characterize a pleometrosis state. In fact, ovarian development analysis from queens showed that the number of queens in the colonies seemed to be unstable. Despite a few cases of oophagy (egg cannibalism), social hierarchy among queens is unclear in comparison to other Pachycondyla species. In addition, aggressiveness increased with distance among nests. Nearby colonies (less than 1 m apart) showed a low level of aggressiveness, suggesting the presence of polydomy, that is, a unique colony can occupy multiple nests. Polygyny associated to polydomy in founding colonies may confer benefits on growth and dispersion of colonies in the studied environments.

  9. Orbital Magnetism of Bloch Electrons I. General Formula

    Science.gov (United States)

    Ogata, Masao; Fukuyama, Hidetoshi

    2015-12-01

    We derive an exact formula of orbital susceptibility expressed in terms of Bloch wave functions, starting from the exact one-line formula by Fukuyama in terms of Green's functions. The obtained formula contains four contributions: (1) Landau-Peierls susceptibility, (2) interband contribution, (3) Fermi surface contribution, and (4) contribution from occupied states. Except for the Landau-Peierls susceptibility, the other three contributions involve the crystal-momentum derivatives of Bloch wave functions. Physical meaning of each term is clarified. The present formula is simplified compared with those obtained previously by Hebborn et al. Based on the formula, it is seen first of all that diamagnetism from core electrons and Van Vleck susceptibility are the only contributions in the atomic limit. The band effects are then studied in terms of linear combination of atomic orbital treating overlap integrals between atomic orbitals as a perturbation and the itinerant feature of Bloch electrons in solids are clarified systematically for the first time.

  10. Weighted Composition Operators from Hardy Spaces into Logarithmic Bloch Spaces

    Directory of Open Access Journals (Sweden)

    Flavia Colonna

    2012-01-01

    Full Text Available The logarithmic Bloch space Blog⁡ is the Banach space of analytic functions on the open unit disk 𝔻 whose elements f satisfy the condition ∥f∥=sup⁡z∈𝔻(1-|z|2log⁡  (2/(1-|z|2|f'(z|<∞. In this work we characterize the bounded and the compact weighted composition operators from the Hardy space Hp (with 1≤p≤∞ into the logarithmic Bloch space. We also provide boundedness and compactness criteria for the weighted composition operator mapping Hp into the little logarithmic Bloch space defined as the subspace of Blog⁡ consisting of the functions f such that lim⁡|z|→1(1-|z|2log⁡  (2/(1-|z|2|f'(z|=0.

  11. Skyrmion clusters from Bloch lines in ferromagnetic films

    KAUST Repository

    Garanin, Dmitry A.

    2017-12-29

    Conditions under which various skyrmion objects emerge in experiments on thin magnetic films remain largely unexplained. We investigate numerically centrosymmetric spin lattices in films of finite thickness with ferromagnetic exchange, magnetic anisotropy, and dipole-dipole interaction. Evolution of labyrinth domains into compact topological structures on application of the magnetic field is found to be governed by the configuration of Bloch lines inside domain walls. Depending on the combination of Bloch lines, the magnetic domains evolve into individual skyrmions, biskyrmions, or more complex topological objects. While the geometry of such objects is sensitive to the parameters, their topological charge is uniquely determined by the topological charge of Bloch lines inside the magnetic domain from which the object emerges.

  12. Time resolved optical Bloch oscillations in porous silicon superlattice structures

    Energy Technology Data Exchange (ETDEWEB)

    Ghulinyan, Mher; Gaburro, Zeno; Pavesi, Lorenzo [Department of Physics, University of Trento and INFM, 38050 Povo (Trento) (Italy); Oton, Claudio J. [Department of Physics, University of Trento and INFM, 38050 Povo (Trento) (Italy); Department of Fundamental Physics, University of La Laguna, La Laguna 38204 Tenerife (Spain); Sapienza, Riccardo; Costantino, Paola; Wiersma, Diederik S. [European Laboratory for Nonlinear Spectroscopy and INFM, 50019 Sesto Fiorentino (Florence) (Italy)

    2005-06-01

    We report on the observation of time resolved Bloch oscillations of light waves in optical superlattice structures. The structures are series of coupled microcavities, which are grown in porous silicon with high control of optical parameters. A controlled linear gradient of refractive index along the growth direction was maintained to tilt the photonic band gap of the superlattice. This is in perfect analogy to the tilted electronic miniband structure of a semiconductor in an electric field. In this way an optical Wannier-Stark ladder of equidistant optical modes was formed. Their frequency separation defines the period of the photon Bloch oscillations. The experimental results are in excellent agreement with transfer matrix calculations. The observed phenomenon is the optical counterpart of the well known electronic Bloch oscillations. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Bloch-wave engineering of quantum dot-micropillars for cavity quantum electrodynamics experiments

    DEFF Research Database (Denmark)

    Lermer, Matthias; Gregersen, Niels; Dunzer, Florian

    2012-01-01

    We have employed Bloch-wave engineering to realize submicron diameter ultra-high quality factor GaAs/AlAs micropillars (MPs). The design features a tapered cavity in which the fundamental Bloch mode is subject to an adiabatic transition to match the Bragg mirror Bloch mode. The resulting reduced...

  14. The anti-Staphylococcus aureus activity of the phenanthrene fraction from fibrous roots of Bletilla striata.

    Science.gov (United States)

    Guo, Jing-Jing; Dai, Bin-Ling; Chen, Ni-Pi; Jin, Li-Xia; Jiang, Fu-Sheng; Ding, Zhi-Shan; Qian, Chao-Dong

    2016-11-29

    Bletillae Rhizoma, the tuber of Bletilla striata, has been used in Chinese traditional medicine to treat infectious diseases. Chemical studies indicated that phenanthrene was one of the most important components of the herb, with a broad spectrum of antibiotic activity against Gram-positive bacteria. The objective of this study was to further characterize the antibacterial activity of the phenanthrene fraction from the fibrous root of the pseudobulb of B. striata. The phenanthrene fraction (EF60) from the ethanol extract of fibrous roots of Bletilla striata pseudobulbs was isolated using polyamide column chromatography. The antibacterial activity of the fraction was evaluated in vitro using a 96-well microtiter plate and microbroth dilution method. The cytotoxicity of EF60 against mammalian cells was tested by hemolysis and MTT assays. EF60 was obtained using alcohol extraction and polyamide column chromatography, with a yield of 14.9 g per 1 kg of the fibrous roots of B. striata. In vitro tests indicated that EF60 was active against all tested strains of Staphylococcus aureus, including clinical isolates and methicillin-resistant S. aureus (MRSA). The minimum inhibitory concentration (MIC) values of EF60 against these pathogens ranged from 8 to 64 μg/mL. Minimum bactericidal concentration tests demonstrated that EF60 was bactericidal against S. aureus 3304 and ATCC 29213 and was bacteriostatic against S. aureus 3211, ATCC 25923, and ATCC 43300. Consistently, the time-kill assay indicated that EF60 could completely kill S. aureus ATCC 29213 at 2× the MIC within 3 h but could kill less than two logarithmic units of ATCC 43300, even at 4× the MIC within 24 h. The postantibiotic effects (PAE) of EF60 (4× MIC) against strains 29213 and 43300 were 2.0 and 0.38 h, respectively. Further studies indicated that EF60 (160 μg/mL) showed no cytotoxicity against human erythrocytes, and was minimally toxic to Human Umbilical Vein Endothelial Cells with an IC50 of 75

  15. Super Bloch oscillations in the Peyrard–Bishop–Holstein model

    Energy Technology Data Exchange (ETDEWEB)

    Herrero-Gómez, C. [GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid (Spain); Díaz, E., E-mail: elenadg@fis.ucm.es [GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid (Spain); Domínguez-Adame, F. [GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid (Spain)

    2012-01-09

    Recently, polarons in the Peyrard–Bishop–Holstein model under DC electric fields were established to perform Bloch oscillations, provided the charge–lattice coupling is not large. In this work, we study this model when the charge is subjected to an applied field with both DC and AC components. Similarly to what happens in the rigid lattice, we find that the carrier undergoes a directed motion or coherent oscillations when the AC field is resonant or detuned with respect to the Bloch frequency, respectively. The electric density current and its Fourier spectrum are also studied to reveal the frequencies involved in the polaron dynamics. -- Highlights: ► We study the Peyrard–Bishop–Holstein model under superimposed DC and AC fields. ► The detuning between the driven and the Bloch frequency sets the polaron dynamics. ► The carrier displays super Bloch oscillations for the non-resonant cases. ► The Morse potential sets the lattice motion which is decoupled of the carrier one. ► The nonlinear coupling leads to a distortion of the wave packet at long times.

  16. Improved Reading Gate For Vertical-Bloch-Line Memory

    Science.gov (United States)

    Wu, Jiin-Chuan; Stadler, Henry L.; Katti, Romney R.

    1994-01-01

    Improved design for reading gate of vertical-Bloch-line magnetic-bubble memory increases reliability of discrimination between binary ones and zeros. Magnetic bubbles that signify binary "1" and "0" produced by applying sufficiently large chopping currents to memory stripes. Bubbles then propagated differentially in bubble sorter. Method of discriminating between ones and zeros more reliable.

  17. Bloch-Like Oscillations in Finite Quantum Structures

    DEFF Research Database (Denmark)

    Duggen, Lars; Willatzen, Morten; Lassen, Benny

    ) and derive rather general mathematical relations between quantum systems that allow the existence of Bloch oscillations. References: [1]: G. Corrielli, A. Crespi, G. Della Valle, S. Longhi, and R. Osellame, Nature Communications 4, 1555 (2013) [2]: H. Sanchis-Alepuz, Y. A. Kosevich, and J. Sanchez-Dehesa...

  18. Feeding habits of the catfish Synodontis schall (Bloch & Schneider ...

    African Journals Online (AJOL)

    Synodontis schall (Bloch & Schneider) is an abundant fish in Lake Chamo, but its feeding ecology is not well-known to guide its management. Diet composition and ... Diatoms, zooplankton and insects constituted 89.8% of the volume of food eaten by juveniles, but their importance declined with the size of fish. Importance of ...

  19. CONSERVATION OF MARIZEIRO Geoffroea striata (Willd. Morong SEEDS USING DIFFERENT PACKAGINGS AND ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    Vênia Camelo de Souza

    2011-03-01

    Full Text Available Geoffroea striata M., commonly known as marizeiro in Brazil, is an important tree species, mainly because it is adapted to riparian forest conditions in semi-arid and associated ecosystems. The species occur in large areas of northeastern Brazil and in the São Francisco river valley, always restricted to seasonally flooded environments. This study aimed to evaluate the effect of different types of packaging and storage periods, as well the influence of environments on the process of seed germination and vigor of Geoffroea striata. The experiment was carried out at the Laboratory of Plant Ecology - CCA//UFPB, following a completely randomized design. The seeds were distributed among two environments (natural conditions in the laboratory and cold room, packed in two types of packaging (paper bags and plastic bags for five periods of storage: 0; 15; 30; 60 and 90 days. Water content, the emergence velocity index, dry weight and length of seedlings were evaluated. The data were submitted to a polynomial regression analysis. In plastic packaging and the environment of the cold room there was less reduction of viability and vigor during storage. Seeds packed in paper bags and stored in a laboratory rapidly lost viability and vigor, after 30 days of storage.

  20. Inner Leaf Gel of Aloe striata Induces Adhesion-Reducing Morphological Hyphal Aberrations

    Directory of Open Access Journals (Sweden)

    Gloria Wada

    2018-02-01

    Full Text Available Fungi, particularly molds that are cosmopolitan in soils, are frequent etiologic agents of opportunistic mycoses. Members of the Fusarium solani and Fusarium oxysporum species complexes are the most commonly implicated etiologic agents of opportunistic fusarial infections in mammals, while Paecilomyces variotii is one of the most frequently encountered Paecilomyces species in human infections. Prevention and treatment of these mycoses are problematic because available antimycotics are limited and often have toxic side effects. Popular folk medicines, such as the inner leaf gel from Aloe spp., offer potential sources for novel antimycotic compounds. To screen for antifungal properties of Aloe striata, we treated conidia of three strains each of F. solani, F. oxysporum, and P. variotii with homogenized and filtered inner leaf gel. Exposure to gel homogenates caused minimal inhibition of conidial germination in tested strains. However, it significantly increased the frequency of hyphal aberrations characterized by increased hyphal diameters that resulted in intervals of non-parallel cell walls. Non-parallel cell walls ostensibly reduce total hyphal surface area available for adhesion. We found a significant decrease in the ability of aberrated P. variotii hyphae to remain adhered to microscope slides after repeated washing with reverse osmosis water. Our results suggest that treatment with A. striata contributes to a decrease in the adhesion frequency of tested P. variotii strains.

  1. Olfactory response of Anastrepha striata (Diptera: Tephritidae) to guava and sweet orange volatiles.

    Science.gov (United States)

    Diaz-Santiz, Edvin; Rojas, Julio C; Cruz-López, Leopoldo; Hernández, Emilio; Malo, Edi A

    2016-10-01

    The behavioral responses of virgin and mated female Anastrepha striata Schiner (Diptera: Tephritidae) to guava (Psidium guajava L.) or sweet orange (Citrus sinensis L.) were evaluated separately using multilure traps in two-choice tests in field cages. The results showed that flies were more attracted to guava and sweet orange volatiles than to control (unbaited trap). The physiological state (virgin or mated) of females did not affect their attraction to the fruit volatiles. Combined analysis of gas chromatography coupled with electroantennography (GC-EAD) of volatile extracts of both fruits showed that 1 and 6 compounds from orange and guava, respectively elicited repeatable antennal responses from mated females. The EAD active compounds in guava volatile extracts were identified by gas chromatography-mass spectrometry (GC-MS) as ethyl butyrate, (Z)-3-hexenol, hexanol, ethyl hexanoate, hexyl acetate, and ethyl octanoate. Linalool was identified as the only antennal active compound in sweet orange extracts. In field cage tests, there were no significant differences between the number of mated flies captured by the traps baited with guava extracts and the number caught by traps baited with the 6-component blend that was formulated according to the relative proportions in the guava extracts. Similar results occurred when synthetic linalool was evaluated against orange extracts. From a practical point of view, the compounds identified in this study could be used for monitoring A. striata populations. © 2015 Institute of Zoology, Chinese Academy of Sciences.

  2. Evidence of birth-and-death evolution of 5S rRNA gene in Channa species (Teleostei, Perciformes).

    Science.gov (United States)

    Barman, Anindya Sundar; Singh, Mamta; Singh, Rajeev Kumar; Lal, Kuldeep Kumar

    2016-12-01

    In higher eukaryotes, minor rDNA family codes for 5S rRNA that is arranged in tandem arrays and comprises of a highly conserved 120 bp long coding sequence with a variable non-transcribed spacer (NTS). Initially the 5S rDNA repeats are considered to be evolved by the process of concerted evolution. But some recent reports, including teleost fishes suggested that evolution of 5S rDNA repeat does not fit into the concerted evolution model and evolution of 5S rDNA family may be explained by a birth-and-death evolution model. In order to study the mode of evolution of 5S rDNA repeats in Perciformes fish species, nucleotide sequence and molecular organization of five species of genus Channa were analyzed in the present study. Molecular analyses revealed several variants of 5S rDNA repeats (four types of NTS) and networks created by a neighbor net algorithm for each type of sequences (I, II, III and IV) did not show a clear clustering in species specific manner. The stable secondary structure is predicted and upstream and downstream conserved regulatory elements were characterized. Sequence analyses also shown the presence of two putative pseudogenes in Channa marulius. Present study supported that 5S rDNA repeats in genus Channa were evolved under the process of birth-and-death.

  3. Genetic diversity and population structure of Anastrepha striata (Diptera: Tephritidae) in three natural regions of southwestern Colombia using mitochondrial sequences.

    Science.gov (United States)

    Gallo-Franco, Jenny Johana; Velasco-Cuervo, Sandra Marcela; Aguirre-Ramirez, Elkin; González Obando, Ranulfo; Carrejo, Nancy Soraya; Toro-Perea, Nelson

    2017-02-01

    Anastrepha striata is widely distributed across the Americas and is a pest of economically important crops, especially crops of the Myrtaceae family. Insect population structures can be influenced by the presence of physical barriers or characteristics associated with habitat differences. This study evaluated the effect of the Western Andes on the population structure of A. striata. Individuals were collected from Psidium guajava fruits from three natural regions of southwestern Colombia (Pacific Coast, mountainous region and the inter-Andean valley of the Cauca River). Based on a 1318 bp concatenated of the genes Cytochrome Oxidase subunit I (COI) and NADH dehydrogenase subunit 6 (ND6), 14 haplotypes with few changes among them (between 1 and 3) were found. There was only one dominant haplotype in all three regions. No genetic structure associated with the three eco-geographical regions of the study was found. Moreover, the Western Andes are not an effective barrier for the genetic isolation of the populations from the Pacific Coast compared with the inter-Andean valley populations. This genetic homogeneity could be partially due to anthropogenic intervention, which acts as a dispersal agent of infested fruits. Another hypothesis to explain the lack of structure would be the relatively recent arrival of A. striata to the region, as indicated by an analysis of the demographic history, which reveals a process of population expansion. This study represents the first attempt to understand the population genetics of A. striata in Colombia and could contribute to the integral management of this pest.

  4. Process optimization and modeling for the cultivation of Nannochloropsis sp. and Tetraselmis striata via response surface methodology.

    Science.gov (United States)

    Imamoglu, Esra; Demirel, Zeliha; Conk Dalay, Meltem

    2015-06-01

    The aim of this study was to determine the optimal physical process conditions for the cultivation of locally isolated strains of Nannochloropsis sp. and Tetraselmis striata to achieve maximum growth rate. It was essential to evaluate biomass production at different agitation rates, light intensities, and temperature levels. Central composite design and response surface methodology were applied to design the experiments and optimize the cultivation process for Nannochloropsis sp. and T. striata. The specific growth rate of 0.250 d(-1) was obtained for Nannochloropsis sp. cells under the light intensity of 54 μmol photons · m(-2) · s(-1) , at the agitation rate of 151 rpm in 24.5°C. The optimal physical process conditions for T. striata were obtained under the light intensity of 56 μmol photons · m(-2) · s(-1) in 25.5°C at the agitation rate of 151 rpm in 25.5°C, resulting in a specific growth rate of 0.226 d(-1) . The predicted values were justified by the verification tests. Good agreement between the predicted values and the experimental values confirmed the validity of the models for the cultivation of microalgal strains. In this article, the noteworthy result was that temperature was a dominant factor in obtaining high chl-a content for Nannochloropsis sp., whereas the growth of T. striata strongly depended on light exposure. © 2015 Phycological Society of America.

  5. Osteopathia striata congenita with cranial sclerosis and intellectual disability due to contiguous gene deletions involving the WTX locus

    DEFF Research Database (Denmark)

    Holman, Sk; Morgan, T; Baujat, G

    2013-01-01

    Osteopathia striata congenita with cranial sclerosis (OSCS) is a skeletal dysplasia caused by germline deletions of or truncating point mutations in the X-linked gene WTX (FAM123B, AMER1). Females present with longitudinal striations of sclerotic bone along the long axis of long bones and cranial...

  6. Acoustic Bloch Wave Propagation in a Periodic Waveguide

    Science.gov (United States)

    1991-07-24

    matrix (Ramo, Whinnery, and Van Duzer , 1965). Given the amplitudes of the two travelling waves in a single cell, then, we can find the amplitudes of...harmonics (Ramo, Whinnery, and Van Duzer , 1965). ; is interesting to note that because the range of the sum index n in Eq. 2.53 includ negative integers...34backwar. wave structures" (Ramo, Whinnery, and Van Duzer , 1965). 2.4.3 The Convolution Representation The apparent simplicity of the Bloch wave function

  7. On history and salvation in Emmanuel Levinas and Ernst Bloch

    Directory of Open Access Journals (Sweden)

    Salomon J. Terreblanche

    2008-01-01

    Full Text Available This article explores the tension between history and salvation as theme in contemporary social and humanist philosophy. Special reference is made to Emmanuel Levinas’ work in order to delineate the scope of the questions involved, and to critically elucidate the position on history, death and hope in new-Marxist philosopher Ernst Bloch. The article then illuminates Levinas’ phenomenological account of fecundity, parenthood, patience and institutional justice as hopeful moments that are contained in his philosophy on history

  8. Cholesteryl-Modification of a Glucomannan from Bletilla striata and Its Hydrogel Properties

    Directory of Open Access Journals (Sweden)

    Mengshan Zhang

    2014-06-01

    Full Text Available A glucomannan-type polysaccharide, named BSP, was obtained from the tubers of Bletilla striata by ultrasonic-assisted extraction, ethanol precipitation, deproteination and gel-permeation chromatography. HPLC analysis revealed that BSP contained mannose and glucose in the molar ratio of 3.5:1. Its molecular weight (Mw was estimated to be 20 kDa. Methylation analysis, FT-IR and NMR analyses indicated that BSP consisted of (1→4-linked β-D-glucopyranosyl residues and (1→4-linked β-D-mannopyranosyl residues. Cholesteryl succinate was linked to BSP to make it more amphiphilic and the degree of substitution of cholesteryl succinate-BSP was 3.2%. The critical micelle concentration of modified BSP was 0.001 mg/mL, suggesting it could self-assemble into nanoparticles in aqueous solution.

  9. Gastroprotective activity of Sterculia striata A. St. Hil. & Naudin (Malvaceae) in rodents.

    Science.gov (United States)

    Sousa, Joubert A; Oliveira, Irisdalva S; Silva, Francilene V; Costa, Danielly A; Chaves, Mariana H; Oliveira, Francisco A; Nunes, Paulo H M; Oliveira, Rita C M

    2012-01-01

    The Sterculia striata ethanolic extract (Ss-EtOH) inhibited gastric lesions induced by ethanol, HCl/ethanol, and ischemia/reperfusion, but not those induced by indomethacin, and did not alter the gastric secretion. Ss-EtOH restored the catalase activity and content of nonprotein sulfhydryl groups in the stomach of mice treated with ethanol. The gastroprotection induced by Ss-EtOH in the ethanol-induced gastric lesion model was abolished by N(G)-nitroL-arginine methyl ester (L-NAME) pretreatment, suggesting the involvement of nitric oxide and antioxidant compounds, but not prostaglandins, in this activity. Lupeol obtained from Ss-EtOH promoted gastroprotection as well as the extract at the same dose, and it must therefore contribute to the observed effects.

  10. Division of Labor in Pachycondyla striata Fr. Smith, 1858 (Hymenoptera: Formicidae: Ponerinae

    Directory of Open Access Journals (Sweden)

    Adolfo da Silva-Melo

    2012-01-01

    Full Text Available Four colonies of the ant Pachycondyla striata were used to analyze the specie behavioral repertoire. Forty-six behavioral acts were recorded in laboratory. Here, we present the record the division of labor between the castes and the temporal polyethism of monomorphic workers. The queens carried out many of the behavioral traits recorded in this work however; they performed them less frequently compared to the worker. The workers activity involved chasing and feeding on fresh insects and usingthem to nourish larvae besides laying eggs in the C-posture, an activity also performed by queens, which is similar to that of wasps of the subfamily Stenogastrinae. The young workers were involved in activities of brood care, sexuate care, and nest maintenance, and the older workers were involved in defense, exploration, and foraging.

  11. PENGGUNAAN MAGGOT SEBAGAI SUBSTITUSI IKAN RUCAH DALAM BUDIDAYA IKAN TOMAN (Channa micropeltes CV.

    Directory of Open Access Journals (Sweden)

    Ediwarman Ediwarman

    2008-12-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui substitusi larva black soldier fly (Hermetia illuscens, fresh maggot sebagai pengganti ikan rucah terhadap keragaan pertumbuhan ikan toman (Channa micropeltes CV. Sebanyak 450 ekor ikan toman dengan bobot rata-rata 6,03 ± 0,69 g dipelihara dalam 15 unit hapa (1 m x 1 m x 1,2 m dengan padat tebar 30 ekor/hapa. Ada 5 tingkatan kombinasi substitusi yaitu: 0%, 25%, 50%, 75%, dan 100% maggot segar dihitung dari bobot kering. Selama 56 hari, pemberian maggot hidup tidak berpengaruh terhadap sintasan. Hasil penelitian memberikan rataan bobot akhir ikan menurun dengan meningkatnya persentase pemberian maggot (27,1 g,  0%; 19,6 g, 25%; 22,1 g, 50%; 14,1 g, 75%; 10,5 g, 100%. Sedangkan pertumbuhan (SGR berkisar antara 0,49%—2,61% hari-1, dengan konversi pakan (FCR, 3,24—14,1. Dari hasil analisis ANOVA dapat disimpulkan bahwa untuk mandapatkan laju pertumbuhan spesifik (SGR yang terbaik, maggot dapat menggantikan ikan rucah sampai 50%, dengan rasio konversi pakan (FCR sebesar 3,31. The aim of this research was to evaluate the effect of fresh black soldier fly (Hermetia illuscens larvae, or fresh maggot, as substitute to trash fish on growth by feeding giant snakehead (Channa micropeltes. Giant snakehead (6.03 ± 0.69 g, mean mass ± SD were reared in 15 hapas (1 m x 1 m x 1.2 m with 30 fish per unit. Five substitution levels were tested: 0%, 25%, 50%, 75%, and 100% fresh maggot on dry mass basis. After 65 days, the utilization of fresh maggot did not affect fish survival rate. Average fish mass at the end of experiment was negatively correlated to the level of substitution of trash fish by fresh maggot (27.1 g, 0%; 19.6 g, 25%; 22.1 g, 50%; 14.1 g, 75%; 10.5 g, 100% while specific growth rate (SGR ranged from 2.61% to 0.49 % day-1 and feed conversion ratio (FCR on dry mass basis ranged from 3.24 to 14.1. Using ANOVA tools, results indicated that fresh maggot can substitute as much as 50% trash fish without

  12. Protection of qubit-coherence on a Bloch sphere

    Science.gov (United States)

    Zong, Xiao-Lan; Chu, Wen-Jing; Yang, Ming; Yang, Qing; Cao, Zhuo-Liang

    2017-07-01

    Single qubit pure state is a fundamental resource in quantum information and quantum computation. Therefore, it is of great importance to protect the coherence of single qubits against decoherence. In this letter, we demonstrate that decoherence caused by spontaneous emission can be effectively suppressed by adding a universal static external field. In order to have an intuitive view to the protection effects and its physical mechanisms, we study the coherence evolution of a single qubit on a Bloch sphere. We can clearly see that different external resonant drivings can rotate the Bloch vector around different axes, and the steady-state solution of the master equation (under protection) are visualized on the Bloch sphere. Furthermore, the frequency detuning between the qubit system and the driving is taken into account, and the results show that our protection scheme still works fine in the detuned cases and the smaller the detuning is, the better the protection effect is. In addition, this protocol can protect the coherence of single qubit states with a wide range of driving parameters, and help people to design simple coherence protection schemes for qubit states. The simplicity and the abundance of the current scheme may warrant its experimental realization.

  13. Pre-germinative treatments to overcome dormancy of Sterculia striata A. St. Hil. & Naldin seedsTratamentos pré-germinativos para superação da dormência de sementes de Sterculia striata A. St. Hil. Naldin

    Directory of Open Access Journals (Sweden)

    Riselane de Lucena Alcântara Bruno

    2012-06-01

    Full Text Available Sterculia striata A. St. Hil. & Naudin. is a native species that is used in reforestation and urban forestry. Displays hard seeds, consisting of problem for the nursery, since their hard seed coats and waterproof hinder and delay germination. This study aimed to determine the effect of pre-germinative treatments in the process of germination of Sterculia striata. The seeds were subjected to six treatments: control – intact seeds (T1, mechanical scarification with sandpaper. 80 opposite the micropylar (T2 with sulfuric acid concentrated by 15, 45 and 60 minutes (T3, T4 and T5 respectively scarification and then immersion in water for 24 hours (T6. The characteristics evaluated were: seedling emergence, emergency first count, speed of emergence, as well as length and dry mass of shoot and root of seedlings. The scarification with sandpaper number 80 on the opposite side of micropylar favors the percentage of seedlings in the first count, and recommended rapid and uniform emergence of seeds of Sterculia striata.Sterculia striata A. St. Hil. & Naudin. é uma espécie nativa que é utilizada em reflorestamentos e na arborização urbana. Apresenta sementes duras, consistindo em problema para os viveiristas, uma vez que seus tegumentos duros e impermeáveis à água dificultam e retardam a germinação. O presente estudo teve como finalidade determinar o efeito de tratamentos pré-germinativos no processo de germinação de sementes de Sterculia striata. As sementes foram submetidas a seis tratamentos: testemunha – sementes intactas (T1, escarificação com lixa n. 80 no lado oposto à micrópila (T2, escarificação com ácido sulfúrico concentrado por 15, 45 e 60 minutos (T3, T4, e T5, respectivamente e escarificação com lixa seguida de imersão em água por 24 horas (T6. As características avaliadas foram: emergência de plântulas, primeira contagem de emergência, índice de velocidade de emergência, bem como comprimento e massa seca da

  14. Utopie am Abgrund. Anmerkungen zum Aufstieg Ernst Blochs - Utopia in the abyss. Remarks on the rise of Ernst Bloch

    Directory of Open Access Journals (Sweden)

    Bernhard Streck

    2012-10-01

    Full Text Available The essay wants to deconstruct the genre of utopias so popular in the 20th century political writings. Human history shows manifold respect to stories about non-existent worlds which mix reality and non-reality, but outside the area of Abrahamitic beliefs there was rarely hope for a future. The secular version of such eschatological teachings begins with Karl Marx in the 19th century and culminates in the prophetic as well as revolutionary writings of Ernst Bloch around the terrible wars of the 20th century. This philosopher succeeded in both parts of post-war Germany and is still venerated inside and outside the academias. Compared with the so-called dystopias of Max Weber, Aldous Huxley or George Orwell the political visions of Bloch lack any sense of reality and seem to be quite useless to the understanding of present tendencies in world politics.

  15. Properties of Floquet-Bloch space harmonics in 1D periodic magneto-dielectric structures

    DEFF Research Database (Denmark)

    Breinbjerg, O.

    2012-01-01

    Recent years have witnessed a significant research interest in Floquet-Bloch analysis for determining the homogenized permittivity and permeability of metamaterials consisting of periodic structures. This work investigates fundamental properties of the Floquet-Bloch space harmonics in a 1......-dimensional magneto-dielectric lossless structure supporting a transverse-electric-magnetic Floquet-Bloch wave; in particular, the space harmonic permittivity and permeability, as well as the space harmonic Poynting vector....

  16. Operational matrix approach for approximate solution of fractional model of Bloch equation

    Directory of Open Access Journals (Sweden)

    Harendra Singh

    2017-04-01

    Full Text Available In present paper operational matrix of integration for Laguerre polynomial is used to solve fractional model of Bloch equation in nuclear magnetic resonance (NMR. The operational matrix converts the Bloch equation in a system of linear algebraic equations. Solving system we obtain the approximate solutions for fractional Bloch equation. Results are compared with existing methods and exact solution. Graphs are plotted for different fractional values of time derivatives.

  17. Does air-breathing meet metabolic demands of the juvenile snakehead, Channa argus, in multiple conditions

    Directory of Open Access Journals (Sweden)

    Yongli Li

    2017-05-01

    Full Text Available The objective of this study was to examine how the respiratory metabolism of the snakehead Channa argus changed when it shifted from breathing water to breathing air, and how increased metabolic demands caused by temperature, feeding, and exhaustive exercise affect its survival in air. The results demonstrated that the oxygen consumption rate (MO2 of the snakehead was lower for aerial respiration than aquatic respiration by 12.1, 24.5 and 20.4% at 20, 25, and 30°C, respectively. Survival time was significantly shortened with increasing temperature and was negatively correlated with the resting MO2 in air (MO2Air. No obvious feeding metabolic response was observed in the snakeheads fed at 1% and 3% body mass levels while breathing air. The maximum MO2Air of the snakehead after exhaustive exercise was significantly higher than the resting MO2Air of the control group. The results suggest that the snakehead could survive out of water by breathing air for varying lengths of time, depending on ambient temperature and metabolic demand. Additionally, some degree of metabolic depression occurs in the snakehead when breathing air. The metabolic demand associated with exercise in the snakehead, but not that associated with feeding, can be supported by its capacity for breathing air to some extent.

  18. Bioaccumulation, oxidative stress and genotoxicity in fish (Channa punctatus) exposed to a thermal power plant effluent.

    Science.gov (United States)

    Javed, Mehjbeen; Ahmad, Irshad; Usmani, Nazura; Ahmad, Masood

    2016-05-01

    Metal bioaccumulation and induction of biomarkers such as lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST), reduced glutathione (GSH) and DNA damage are potential indicators of stress in Channa punctatus exposed to effluents. In canal water, receiving thermal power plant discharges, Fe and Ni concentrations exceeded the recommended guidelines set by the United Nations Environment Programme Global Environment Monitoring System (UNEPGEMS). Fe was highly bioavailable and accumulated in all organs (liver, kidney, muscle and integument). The highest metal pollution index (MPI) value of 41.2 was observed in kidney and the lowest 13.5 in muscle tissue. LPO, SOD, CAT and GST levels were significantly higher in liver and kidney, whereas GSH levels declined significantly compared to fish from the reference site. Concomitant damage to DNA was observed with significantly higher mean tail length in the exposed fish gill cells (26.5µm) and in liver (20.8µm) compared to reference fish. Therefore, it can be concluded that the thermal power plant effluent had the potential to cause oxidative stress and DNA damage in C. punctatus. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. PCR-RFLP analysis of mitochondrial DNA cytochrome b gene among Haruan (Channa striatus) in Malaysia.

    Science.gov (United States)

    Rahim, Mohamamd Hafiz Abdul; Ismail, Patimah; Alias, Rozila; Muhammad, Norwati; Mat Jais, Abdul Manan

    2012-02-15

    Haruan (Channa striatus) is in great demand in the Malaysian domestic fish market. In the present study, mtDNA cyt b was used to investigate genetic variation of C. striatus among populations in Peninsular Malaysia. The overall population of C. striatus demonstrated a high level of haplotype diversity (h) and a low-to-moderate level of nucleotide diversity (π). Analysis of molecular variance (AMOVA) results showed a significantly different genetic differentiation among 6 populations (F(ST)=0.37566, P=0.01). Gene flow (Nm) was high and ranged from 0.32469 to infinity (∞). No significant relationship between genetic distance and geographic distance was detected. A UPGMA tree based on the distance matrix of net interpopulation nucleotide divergence (d(A)) and haplotype network of mtDNA cyt b revealed that C. striatus is divided into 2 major clades. The neutrality and mismatch distribution tests for all populations suggested that C. striatus in the study areas had undergone population expansion. The estimated time of population expansion in the mtDNA cyt b of C. striatus populations occurred 0.72-6.19 million years ago. Genetic diversity of mtDNA cyt b and population structure among Haruan populations in Peninsular Malaysia will be useful in fisheries management for standardization for Good Agriculture Practices (GAP) in fish-farming technology, as well as providing the basis for Good Manufacturing Practices (GMP). Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Optimizing protein and lipid levels in practical diet for juvenile northern snakehead fish (Channa argus

    Directory of Open Access Journals (Sweden)

    Gladstone Sagada

    2017-06-01

    Full Text Available A 3 × 3 factorial feeding trial was conducted to evaluate the production response of juvenile northern snakehead fish (Channa argus. Nine diets containing 3 protein levels (45%, 48% and 51% and 3 lipid levels (9%, 12% and 15% were formulated and fed to triplicate groups of juvenile northern snakehead (15.78 ± 0.09 g/fish for 8 weeks. The formulated diets were named as P45L9, P45L12, P45L15, P48L9, P48L12, P48L15, P51L9, P51L12 and P51L15 (P-Protein, L-Lipid, respectively. Fish fed diets with the lowest protein and lipid combination (P45L9 had the lowest growth performance. Weight gains (WG of fish fed the 4 diets P48L12, P48L15, P51L9, and P51L12 were not significantly different (P > 0.05, but significantly higher (P  0.05 by dietary treatments. Based on these results, the diet containing 48% protein with either 12% or 15% lipid is the optimal for supporting growth and feed utilization of juvenile northern snakehead under the current testing conditions.

  1. Constituintes químicos, fenóis totais e atividade antioxidante de Sterculia striata St. Hil. et Naudin Chemical constituents, total phenolics and antioxidant activity of Sterculia striata St. Hil. et Naudin

    Directory of Open Access Journals (Sweden)

    Danielly Albuquerque Costa

    2010-03-01

    Full Text Available A investigação fitoquímica das cascas do caule de Sterculia striata St. Hil. et Naudin, através de métodos cromatográficos, conduziu ao isolamento dos esteróides sitosterol, estigmasterol e sitosterol-3-O-β-D-glicopiranosídeo, além de quatro triterpenóides pentacíclicos, o lupeol, 3-β-O-acil lupeol, lupenona e ácido betulínico. As estruturas desses compostos foram identificadas por análise dos espectros de RMN ¹H e 13C e comparações com dados da literatura. Para determinação do teor de fenóis totais do extrato etanólico de S. striata utilizou-se o reativo Folin Ciocalteu, enquanto na avaliação da atividade antioxidante empregou-se o radical livre DPPH. Este é o primeiro trabalho descrevendo o estudo químico com as cascas do caule desta espécie.The phytochemical investigation of the stem bark of Sterculia striata St. Hil. et Naudin by chromatographic methods led to the isolation of sitosterol, stigmasterol and sitosterol-3-O-β-D-glucopyranoside, besides pentacyclic triterpenoids, lupeol, 3-β-O-acyl-lupeol, lupenone and betulinic acid. The structures of these compounds were identified by ¹H and 13C NMR spectral data analysis and comparison with literature data. For determining of the phenolic content of the etanolic extract of Sterculia striata we used the Folin Ciocalteu reagent, and for the evaluation of antioxidant activity, we utilized the DPPH free radical. This is the first work reporting the chemical study with the stem bark of this species.

  2. Nesting and reproduction of Pachycondyla striata (Formicidae: Ponerinae in urban areas: an ant that offers risk of accidents

    Directory of Open Access Journals (Sweden)

    Stefano Marco Cantone

    2015-07-01

    Full Text Available It was conducted a research, in urban areas, on the nesting habits and reproductive period of Pachycondyla striata, a species of ant that stings painfully. The study was motivated by the frequent reports of accidents in the city of São Paulo. The reports are more common during the reproductive seasons of the species, when the winged females sting the population, since they enter the houses of the people attracted to light. Although anaphylaxis for P. striata has not been reported yet, other close species may cause anaphylaxis, which makes important to understand their biology in order to take management and control measures. Fourteen green areas in the city of São Paulo, Brazil, were monitored in the search for the species and their nests that were found in 64.3% of the areas. The nests are located around the trunk base of the trees, between the roots that protrude from the ground, under the rocks and through the cracks and crevices on the sidewalks. The spatial distribution of the nests is random. The reproductive period of P. striata was monitored from April 2012 to November 2013, through passive collection and laboratory colony. The nuptial flights occur during the cooler and drier months of the year, between July and September.

  3. Bipolaron assisted Bloch-like oscillations in organic lattices

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Luiz Antonio, E-mail: ribeirojr@unb.br [International Center for Condensed Matter Physics, University of Brasília, P.O. Box 04531, 70.919-970, Brasília, DF (Brazil); University of Brasília, UnB Faculty of Planaltina, 73.345-010, Planaltina, DF (Brazil); Ferreira da Cunha, Wiliam; Magela e Silva, Geraldo [Institute of Physics, University of Brasília, 70.919-970, Brasília (Brazil)

    2017-06-15

    The transport of a dissociated bipolaron in organic one-dimensional lattices is theoretically investigated in the scope of a tight-binding model that includes electron-lattice interactions and an external electric field. Remarkably, the results point to a physical picture in which the dissociated bipolaron propagates as a combined state of two free-like electrons that coherently perform spatial Bloch oscillations (BO) above a critical field strength. It was also obtained that the BO's trajectory presents a net forward motion in the direction of the applied electric field. The impact of dynamical disorder in the formation of electronic BOs is determined.

  4. Traffic restrictions on Routes Bloch, Maxwell and Bohr

    CERN Multimedia

    TS Department

    2008-01-01

    Excavation and pipework is being carried out in the framework of the transfer of the waste water treatment plant for the effluents from the surface treatment workshops from Building 254 to Building 676, currently under construction. This work may encroach onto Routes Bloch, Maxwell and Bohr and disrupt the flow of traffic. Users are requested to comply with the road signs that will be erected. The work is expected to last until the beginning of December 2008. Thank you for your understanding. TS/CE and TS/FM Groups Tel.7 4188 or 16 4314

  5. Lie-Poisson bifurcations for the Maxwell-Bloch equations

    Energy Technology Data Exchange (ETDEWEB)

    David, D.

    1990-01-01

    We present a study of the set of Maxwell-Bloch equations on R{sup 3} from the point of view of Hamiltonian dynamics. These equations are shown to be bi-Hamiltonian, on the one hand, and to possess several inequivalent Lie-Poisson structures, on the other hand, parametrized by the group SL(2,R). Each structure is characterized by a particular distinguished function. The level sets of this function provide two-dimensional surfaces onto which the motion takes various symplectic forms. 4 refs.

  6. Bloch electrons in 2D periodic electric and magnetic fields; Bloch-Elektronen in 2D periodischen elektrischen und magnetischen Feldern

    Energy Technology Data Exchange (ETDEWEB)

    Naundorf, B.

    2001-06-01

    The following topics were dealt with: electrons in periodic potentials, Bloch states, Landau states, wave packets, Harper equation, uncoupled Landau band states, matrix elements and matrix equations, periodic electric and magnetic fields (WL)

  7. Bloch-Redfield equations for modeling light-harvesting complexes.

    Science.gov (United States)

    Jeske, Jan; Ing, David J; Plenio, Martin B; Huelga, Susana F; Cole, Jared H

    2015-02-14

    We challenge the misconception that Bloch-Redfield equations are a less powerful tool than phenomenological Lindblad equations for modeling exciton transport in photosynthetic complexes. This view predominantly originates from an indiscriminate use of the secular approximation. We provide a detailed description of how to model both coherent oscillations and several types of noise, giving explicit examples. All issues with non-positivity are overcome by a consistent straightforward physical noise model. Herein also lies the strength of the Bloch-Redfield approach because it facilitates the analysis of noise-effects by linking them back to physical parameters of the noise environment. This includes temporal and spatial correlations and the strength and type of interaction between the noise and the system of interest. Finally, we analyze a prototypical dimer system as well as a 7-site Fenna-Matthews-Olson complex in regards to spatial correlation length of the noise, noise strength, temperature, and their connection to the transfer time and transfer probability.

  8. Bloch-Zener oscillations in a tunable optical honeycomb lattice

    Energy Technology Data Exchange (ETDEWEB)

    Uehlinger, Thomas; Greif, Daniel; Jotzu, Gregor; Esslinger, Tilman [Institute for Quantum Electronics, ETH Zurich, 8093 Zurich (Switzerland); Tarruell, Leticia [Institute for Quantum Electronics, ETH Zurich, 8093 Zurich, Switzerland and LP2N, Universite Bordeaux 1, IOGS, CNRS, 351 cours de la Liberation, 33405 Talence (France)

    2013-12-04

    Ultracold gases in optical lattices have proved to be a flexible tool to simulate many different phenomena of solid state physics [1, 2]. Recently, optical lattices with complex geometries have been realized [3, 4, 5, 6, 7], paving the way to simulating more realistic systems. The honeycomb structure has recently become accessible in an optical lattice composed of mutually perpendicular laser beams. This lattice structure exhibits topological features in its band structure – the Dirac points. At these points, two energy bands intersect linearly and the particles behave as relativistic Dirac fermions. In optical lattices, Bloch oscillations [8] resolved both in time and in quasi-momentum space can be directly observed. We make use of such Bloch-Zener oscillations to probe the vanishing energy gap at the Dirac points as well as their position in the band structure. In small band gap regions, we observe Landau-Zener tunneling [7, 9] to the second band and the regions of maximum transfer can be identified with the position of the Dirac points.

  9. The role of a water bug, Sigara striata, in freshwater food webs

    Directory of Open Access Journals (Sweden)

    Jan Klecka

    2014-05-01

    Full Text Available Freshwater food webs are dominated by aquatic invertebrates whose trophic relationships are often poorly known. Here, I used laboratory experiments to study the role of a water bug, Sigara striata, as a potential predator and prey in food webs of stagnant waters. Multiple-choice predation experiment revealed that Sigara, which had been considered mostly herbivorous, also consumed larvae of Chironomus midges. Because they often occur in high densities and are among the most ubiquitous aquatic insects, Sigara water bugs may be important predators in fresh waters. A second experiment tested the role of Sigara as a potential prey for 13 common invertebrate predators. Mortality of Sigara inflicted by different predators varied widely, especially depending on body mass, foraging mode (ambush/searching and feeding mode (chewing/suctorial of the predators. Sigara was highly vulnerable to ambush predators, while searching predators caused on average 8.1 times lower mortality of Sigara. Additionally, suctorial predators consumed on average 6.6 times more Sigara individuals than chewing predators, which supports previous results hinting on potentially different predation pressures of these two types of predators on prey populations. The importance of these two foraging-related traits demonstrates the need to move from body mass based to multiple trait based descriptions of food web structure. Overall, the results suggests that detailed experimental studies of common but insufficiently known species can significantly enhance our understanding of food web structure.

  10. Silymarin-Loaded Nanoparticles Based on Stearic Acid-Modified Bletilla striata Polysaccharide for Hepatic Targeting

    Directory of Open Access Journals (Sweden)

    Yanni Ma

    2016-02-01

    Full Text Available Silymarin has been widely used as a hepatoprotective drug in the treatment of various liver diseases, yet its effectiveness is affected by its poor water solubility and low bioavailability after oral administration, and there is a need for the development of intravenous products, especially for liver-targeting purposes. In this study, silymarin was encapsulated in self-assembled nanoparticles of Bletilla striata polysaccharide (BSP conjugates modified with stearic acid and the physicochemical properties of the obtained nanoparticles were characterized. The silymarin-loaded micelles appeared as spherical particles with a mean diameter of 200 nm under TEM. The encapsulation of drug molecules was confirmed by DSC thermograms and XRD diffractograms, respectively. The nanoparticles exhibited a sustained-release profile for nearly 1 week with no obvious initial burst. Compared to drug solutions, the drug-loaded nanoparticles showed a lower viability and higher uptake intensity on HepG2 cell lines. After intravenous administration of nanoparticle formulation for 30 min to mice, the liver became the most significant organ enriched with the fluorescent probe. These results suggest that BSP derivative nanoparticles possess hepatic targeting capability and are promising nanocarriers for delivering silymarin to the liver.

  11. Chitosan/Sterculia striata polysaccharides nanocomplex as a potential chloroquine drug release device.

    Science.gov (United States)

    Magalhães, Guilherme A; Moura Neto, Erico; Sombra, Venícios G; Richter, Ana R; Abreu, Clara M W S; Feitosa, Judith P A; Paula, Haroldo C B; Goycoolea, Francisco M; de Paula, Regina C M

    2016-07-01

    Nanoparticles are produced by means of polyelectrolyte complexation (PEC) of oppositely charged polycationic chitosan (CH) with polyanionic polysaccharide extracted from Sterculia striata exudates (rhamnogalacturonoglycan (RG)-type polysaccharide). The nanoparticles formed with low-molar-mass CH are larger than those formed with high-molar-mass CH. This behavior is in contrast with that previously observed for other systems and may be attributed to different mechanisms related to the association of CH with RG of higher persistence length chain than that of CH. Nanoparticles harnessed with a charge ratio (n(+)/n(-)) of <1 are smaller than particles with an excess of polycations. Particles with hydrodynamic sizes smaller than 100nm are achieved using a polyelectrolyte concentration of 10(-4)gmL(-1) and charge ratio (n(+)/n(-)) of <1. The CH/RG nanoparticles are associated with chloroquine (CQ) with an efficiency of 28% and release it for up to ∼60% within ∼10h, whereas in the latter, only ∼40% of the CQ was released after 24h. The main factor that influenced drug release rate is the nanoparticle charge ratio. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. A blood group A specific lectin from the seeds of Crotalaria striata.

    Science.gov (United States)

    Khang, N Q; Jean-Luc, G; Hoebeke, J

    1990-02-26

    A lectin, monospecific for human blood group A red blood cells was extracted from seeds of Crotalaria striata and purified by molecular sieving on Sephadex G-100 and ion-exchange on DEAE-cellulose. A molecular mass of 30 kDa was determined by SDS-polyacrylamide gel electrophoresis under non-reducing and reducing conditions. Molecular sieving on a Superose 12 column indicated a molecular mass of 110 kDa, suggesting the tetrameric nature of the native protein. Amino-acid composition showed the presence of aminated carbohydrate residues on the lectin. N-terminal amino-acid sequencing showed a striking similarity with the N-terminal sequence of the lectin from Crotalaria juncea, which is blood-group non-specific. The potency order of agglutination inhibition with galactose containing monosaccharides was N-acetyl-D-galactosamine greater than D-galactose greater than D-galactosamine as found for blood-group-A-specific lectins from other species.

  13. Venom gland of Pachycondyla striata worker ants (Hymenoptera: Ponerinae). Ultrastructural characterization.

    Science.gov (United States)

    Ortiz, Gabriela; Mathias, Maria Izabel Camargo

    2006-01-01

    Morphological data concerning the venom gland of worker ants of Pachycondyla striata revealed that this gland consists of three distinct regions: an external secretory portion, composed by a secretory filament that bifurcates in order to give rise to other two filaments; an internal secretory portion, represented by the convoluted gland; and a storage portion, represented by a sac-shaped reservoir. The ultrastructural analysis showed that the reservoir is enveloped by a simple pavementous epithelium, coated internally with a cuticle. The external secretory portion is composed by cells forming a simple cubic epithelium, in which the apical portion presents numerous microvilli while the basal portion of the cells shows infoldings of the plasma membrane containing numerous mitochondria. The convoluted gland possesses cells of irregular morphology with nuclei containing condensed chromatin, suggesting inactivity. However, these cells are in fact undergoing secretory activity, which is probably added to the final secretion produced by the gland. The cytoplasm of these cells contains several elements distributed therein, such as ribosomes and polyribosomes, lipid droplets, and protein inclusions in the form of crystals, thus suggestive of protein storage, which would be used by the insect when metabolically required.

  14. Leaky Bloch-like surface waves in the radiation-continuum for sensitivity enhanced biosensors via azimuthal interrogation.

    Science.gov (United States)

    Koju, Vijay; Robertson, William M

    2017-06-12

    Dielectric multilayer structures with a grating profile on the top-most layer adds an additional degree of freedom to the phase matching conditions for Bloch surface wave excitation. The conditions for Bloch surface wave coupling can be achieved by rotating both polar and azimuthal angles. The generation of Bloch surface waves as a function of azimuthal angle has similar characteristics to conventional grating coupled Bloch surface waves. However, azimuthally generated Bloch surface waves have enhanced angular sensitivity compared to conventional polar angle coupled modes, which makes them appropriate for detecting tiny variations in surface refractive index due to the addition of nano-particles such as protein molecules.

  15. From Bloch to random lasing in ZnO self-assembled nanostructures

    DEFF Research Database (Denmark)

    Garcia-Fernandez, Pedro David; Cefe, López

    2013-01-01

    In this paper, we present measurements on UV lasing in ZnO ordered and disordered nanostructures. Bloch lasing is achieved in the ordered structures by exploiting very low group-velocity Bloch modes in ZnO photonic crystals. In the second case, random lasing is observed in ZnO photonic glasses. We...... study the lasing threshold in both cases and its dependence on the structural parameters. Finally, we present the transition from Bloch to random lasing by deliberately doping a ZnO inverse photonic crystal with a controlled amount of lattice vacancies effectively converting it into a translationally...

  16. The Optical Bloch oscillation in chirped one-dimensional superconducting photonic crystal

    Science.gov (United States)

    Zhang, Zhengren; Long, Yang; Zhang, Liwei; Yin, Pengfei; Xue, Chunhua

    2017-09-01

    We exploit theoretically the propagation properties of electromagnetic waves in nanoscale one-dimensional superconducting photonic crystal. The Wannier Stark ladders can be formed in the photonic crystal by varying the thickness of the dielectric layers linearly across the structure. The dynamics behavior of a Gaussian pulse transmitting through the structure is simulated theoretically. We find that photons undergo Bloch oscillations inside tilted photonic bands and the Bloch oscillations are sensitive to the change of temperature in the range of 3-8 K. It is demonstrated that our structure is possible to realize tunable optical Bloch oscillations by controlling the temperature of superconducting material.

  17. Bloch-Messiah reduction of Gaussian unitaries by Takagi factorization

    Science.gov (United States)

    Cariolaro, Gianfranco; Pierobon, Gianfranco

    2016-12-01

    The Bloch-Messiah (BM) reduction allows the decomposition of an arbitrarily complicated Gaussian unitary into a very simple scheme in which linear optical components are separated from nonlinear ones. The nonlinear part is due to the squeezing possibly present in the Gaussian unitary. The reduction is usually obtained by exploiting the singular value decomposition (SVD) of the matrices appearing in the Bogoliubov transformation of the given Gaussian unitary. This paper discusses a different approach, where the BM reduction is obtained in a straightforward way. It is based on the Takagi factorization of the (complex and symmetric) squeeze matrix and has the advantage of avoiding several matrix operations of the previous approach (polar decomposition, eigendecomposition, SVD, and Takagi factorization). The theory is illustrated with an application example in which the previous and present approaches are compared.

  18. DAGON: a 3D Maxwell-Bloch code

    Science.gov (United States)

    Oliva, Eduardo; Cotelo, Manuel; Escudero, Juan Carlos; González-Fernández, Agustín.; Sanchís, Alberto; Vera, Javier; Vicéns, Sergio; Velarde, Pedro

    2017-05-01

    The amplification of UV radiation and high order harmonics (HOH) in plasmas is a subject of raising interest due to its different potential applications in several fields like environment and security (detection at distance), biology, materials science and industry (3D imaging) and atomic and plasma physics (pump-probe experiments). In order to develop these sources, it is necessary to properly understand the amplification process. Being the plasma an inhomogeneous medium which changes with time, it is desirable to have a full time-dependent 3D description of the interaction of UV and XUV radiation with plasmas. For these reasons, at the Instituto de Fusíon Nuclear we have developed DAGON, a 3D Maxwell-Bloch code capable of studying the full spationtemporal structure of the amplification process abovementioned.

  19. Kalb-Ramond field localization on the Bloch brane

    Science.gov (United States)

    Cruz, W. T.; Maluf, R. V.; Almeida, C. A. S.

    2013-08-01

    This work deals with new results on the Kalb-Ramond (KR) field localization in brane-world models. We consider a five-dimensional warped spacetime with an embedded 4D thick brane which is generated by two real scalar fields coupled with gravity (the so called Bloch brane). We find a KR field zero mode localized with the inclusion of the dilaton coupling. Analyzing the massive spectrum, we detected a series of resonant modes that arise from the solutions of the Schrödinger-like equation for KR field. The effects of the brane thickness and of the dilaton coupling over the resonance structures are determined. Such analysis is extended to the resonance lifetimes of the massive modes, allowing a better understanding on the localization mechanism of the model.

  20. Entanglement and the three-dimensionality of the Bloch ball

    Energy Technology Data Exchange (ETDEWEB)

    Masanes, Ll., E-mail: ll.masanes@gmail.com [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Müller, M. P. [Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 19, D-69120 Heidelberg (Germany); Pérez-García, D. [Departamento de Analisis Matematico and IMI, Universidad Complutense de Madrid, 28040 Madrid (Spain); Augusiak, R. [ICFO-Institut de Ciencies Fotoniques, 08860 Castelldefels, Barcelona (Spain)

    2014-12-15

    We consider a very natural generalization of quantum theory by letting the dimension of the Bloch ball be not necessarily three. We analyze bipartite state spaces where each of the components has a d-dimensional Euclidean ball as state space. In addition to this, we impose two very natural assumptions: the continuity and reversibility of dynamics and the possibility of characterizing bipartite states by local measurements. We classify all these bipartite state spaces and prove that, except for the quantum two-qubit state space, none of them contains entangled states. Equivalently, in any of these non-quantum theories, interacting dynamics is impossible. This result reveals that “existence of entanglement” is the requirement with minimal logical content which singles out quantum theory from our family of theories.

  1. Rhizobium taibaishanense sp. nov., isolated from a root nodule of Kummerowia striata.

    Science.gov (United States)

    Yao, Li Juan; Shen, Yao Yao; Zhan, Jun Peng; Xu, Wei; Cui, Guang Ling; Wei, Ge Hong

    2012-02-01

    During a study of the diversity and phylogeny of rhizobia in the root nodules of Kummerowia striata grown in north-western China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. The 16S rRNA gene sequences of three of these strains were identical and that of the other strain, which was the only one isolated in Yangling, differed from the others by just 1 bp. The16S rRNA gene sequences of the four strains showed a mean similarity of 99.3 % with the most closely related, recognized species, Rhizobium vitis. The corresponding recA and glnA gene sequences showed similarities with established species of Rhizobium of less than 86.5 % and less than 89.6 %, respectively. These low similarities indicated that the four strains represented a novel species of the genus Rhizobium. The strains were also found to be distinguishable from the closest related, established species (R. vitis) by rep-PCR DNA fingerprinting, analysis of cellular fatty acid profiles and from the results of a series of phenotypic tests. The level of DNA-DNA relatedness between the representative strain CCNWSX 0483(T) and Rhizobium vitis IAM 14140(T) was only 40.13 %. Therefore, a novel species, Rhizobium taibaishanense sp. nov., is proposed, with strain CCNWSX 0483(T) ( = ACCC 14971(T) = HAMBI 3214(T)) as the type strain. In nodulation and pathogenicity tests, none of the four strains of Rhizobium taibaishanense sp. nov. was able to induce any nodule or tumour formation on plants. As no amplicons were detected when DNA from the strains was run in PCR with primers for the detection of nodA, nifH and virC gene sequences, the strains probably do not carry sym or vir genes.

  2. Nesting and reproduction of Pachycondyla striata (Formicidae: Ponerinae) in urban areas: an ant that offers risk of accidents

    OpenAIRE

    Stefano Marco Cantone; Ana Eugênia de Carvalho Campos

    2015-01-01

     It was conducted a research, in urban areas, on the nesting habits and reproductive period of Pachycondyla striata, a species of ant that stings painfully. The study was motivated by the frequent reports of accidents in the city of São Paulo. The reports are more common during the reproductive seasons of the species, when the winged females sting the population, since they enter the houses of the people attracted to light. Although anaphylaxis for P. striata has not been reported yet, other ...

  3. AMINO ACID COMPOSITION OF SNAKEHEAD FISH (CHANNA STRIATUS OF VARIOUS SIZES OBTAINED AT DIFFERENT TIMES OF THE YEAR

    Directory of Open Access Journals (Sweden)

    LAY-HARN GAM

    2005-01-01

    Full Text Available Snakehead fish (Channa striatus or Haruan is one of the favourite fresh water fish in the Asia-Pacific countries. The fish has been traditionally used to heal wounds. The amino acid composition of wild type Haruan was analyzed in this study. The most abundant amino acid in Haruan was glutamic acid, followed by aspartic acid, lysine, arginine, leucine, alanine, valine, threonine and glycine, in a decreasing order. The Haruan caught during rainy season was found to contain higher amount of total amino acids. The essential amino acids made up 56% of its total amino acids content. Furthermore, each of the essential amino acids (except lysine was found in higher quantity compared to other types of fishes. Haruan was found significantly rich in arginine, an important constituent in the process of wound healing. The amino acid composition of Haruan indicates that the fish is an excellent source of dietary protein for human.

  4. Comparative analysis on microbial community associated with different gastrointestinal regions of wild northern snakehead Channa argus Cantor, 1842

    Science.gov (United States)

    Miao, Shuyan; Zhao, Chenze; Zhu, Jinyu; Pan, Mingzhu

    2017-06-01

    Microbial communities in different gastrointestinal regions (stomach, foregut, midgut, and hindgut) of the northern snakehead Channa argus (Cantor, 1842) were compared by polymerase chain reaction and partial 16S rDNA sequencing. A total of 194, 140, 212, and 122 OTUs were detected in the stomach, foregut, midgut, and hindgut, respectively. Significant differences were found in the Sobs, ACE, Shannon, and Simpson indices among samples (P Prevotella were the highest in the midgut (P Prevotella; and hindgut, Cetobacterium and Plesiomonas (P Prevotella copri and Clostridium perfring were not detected in the foregut and midgut, respectively, whereas Prevotella copri and Faecalibacterium pra were not detected in the hindgut. These findings provide valuable information on the microbial community in each gastrointestinal region of C. argus. Moreover, this study indicated that microbial community was not only related to rearing environment but also to the physico-chemical characteristics of each gastrointestinal region.

  5. Role of catecholamines and nitric oxide on pigment displacement of the chromatophores of freshwater snakehead teleost fish, Channa punctatus.

    Science.gov (United States)

    Biswas, Saikat P; Jadhao, Arun G; Palande, Nikhil V

    2014-04-01

    We are reporting for the first time that the catecholamines (adrenaline and noradrenaline) inhibit the effect of nitric oxide (NO) on melanosome dispersion in freshly isolated scales of the freshwater snakehead fish, Channa punctatus. We studied the effect of NO and catecholamines on the pigment displacement by observing the changes in the melanophore index. The scales when treated with solution containing NO donor sodium nitroprusside (SNP) showed dispersion of melanosomes, whereas NO synthase blocker N-omega-Nitro-L-arginine suppresses this action of SNP. Treatment with adrenaline and noradrenaline on the isolated scales caused aggregation of melanosomes. Scales treated with solution containing catecholamines and SNP resulted in aggregation of melanosomes suggesting that catecholamines mask the effect of SNP. These results suggest that the catecholamines are inhibiting the effect of NO and causing the aggregation of the melanosomes may be via surface receptors.

  6. Evaluation of cytochrome b mtDNA sequences in genetic diversity studies of Channa marulius (Channidae: Perciformes).

    Science.gov (United States)

    Habib, Maria; Lakra, W S; Mohindra, Vindhya; Khare, Praveen; Barman, A S; Singh, Akanksha; Lal, Kuldeep K; Punia, Peyush; Khan, Asif A

    2011-02-01

    Channa marulius (Hamilton, 1822) is a commercially important freshwater fish and a potential candidate species for aquaculture. The present study evaluated partial Cytochrome b gene sequence of mtDNA for determining the genetic variation in wild populations of C. marulius. Genomic DNA extracted from C. marulius samples (n = 23) belonging to 3 distant rivers; Mahanadi, Teesta and Yamuna was analyzed. Sequencing of 307 bp Cytochrome b mtDNA fragment revealed the presence of 5 haplotypes with haplotype diversity value of 0.763 and nucleotide diversity value of 0.0128. Single population specific haplotype was observed in Mahanadi and Yamuna samples and 3 haplotypes in Teesta samples. The analysis of data demonstrated the suitability of partial Cytochrome b sequence in determining the genetic diversity in C. marulius population.

  7. Bloch-surface-waves based photonic devices studied by leakage radiation microscopy

    Science.gov (United States)

    Gulkin, D. N.; Abrashitova, K. A.; Safronov, K. R.; Kokareva, N. G.; Antropov, I. M.; Bessonov, V. O.; Fedyanin, A. A.

    2017-09-01

    The Bloch-surface-wave photonic devices were for the first time manufactured by the two-photon polymerization lithography. Bloch-surface-wave modes excitation and propagation were visualized by the leakage radiation microscopy. The mode structure of the guided light was characterized by the back-focal-plane imaging. It was demonstrated that the photonic devices are able to guide light in multimode regime.

  8. Bloch wave deafness and modal conversion at a phononic crystal boundary

    OpenAIRE

    Vincent Laude; Rayisa P. Moiseyenko; Sarah Benchabane; Nico F. Declercq

    2011-01-01

    International audience; We investigate modal conversion at the boundary between a homogeneous incident medium and a phononic crystal, with consideration of the impact of symmetry on the excitation of Bloch waves. We give a quantitative criterion for the appearance of deaf Bloch waves, which are antisymmetric with respect to a symmetry axis of the phononic crystal, in the frame of generalized Fresnel formulas for reflection and transmission at the phononic crystal boundary. This criterion is u...

  9. Some aspects in early life stage of snake head fish, Channa striatus larvae

    Directory of Open Access Journals (Sweden)

    Thumronk Amornsakun1*,

    2011-12-01

    Full Text Available The sexual maturity of female snake head fish, Channa striatus was studied by determining fecundity and gonadosomaticindex (GSI. It was found that the size at sexual maturity of female snake head fish was 26.45±3.07 cm (mean ± SD,n=10 in total length and 167.4±48.09 g in body weight. The eggs were floating and rounded. The fertilized eggs had a diameterof 588±20.43 m. The fecundity was 10,279.1±2,527.9 ova/fish and gonadosomatic index (GSI was 5.07±1.04 %.Newly hatched larvae of snake head fish were produced by induced spawning using chemical injection (Suprefactand Motilium. The sexually mature fishes were cultured in a fiber-glass tank (water volume 300 liters with the ratio of maleand female brooders 1:1. The fertilization rate, hatching out and hatching rate experiments were carried out using 3 15-literglass aquaria (water volume 10 liters each containing 1,000 eggs. It was found that the average fertilization rate was 76.50%,hatching out occurred of 28 hr 40 min and average hatching rate was 60.26 % at a water temperature of 26.5-29.0°C. Samplingof the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10%buffered formalin for later determination of yolk absorption time. Observation using a microscope revealed that newlyhatched larvae were 3.18±0.11 mm in total length and had yolk sacs of 1,279.71±196.10 m3 in volume. The yolk sacs werecompletely absorbed within 80 hr after hatching at a water temperature of 26.5-29.0°C. Up until full mouth development (startof feeding, 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size ofmouth opening. All the larvae had open mouths about 52 hr after hatching (5.48±0.16 mm TL, and measured 324.30±144.60m in mouth opening.The feeding experiments were carried out using a 15-liter glass aquarium (water volume 10 liters containing 1,000larvae aged 1.5 days post-hatching (just before

  10. Caracterização química do óleo da amêndoa de Sterculia striata St. Hil. et Naud

    Directory of Open Access Journals (Sweden)

    Chaves Mariana H.

    2004-01-01

    Full Text Available This paper describes total lipid content, unsaponifiable fraction and the acid, refractive, saponification and iodine indices of the oil of Sterculia striata nuts. The fatty acids, the sterols and the triterpene alcohols were determined. The percentage of cyclopropenoid fatty acids (CPFA, determined by NMR ¹H (15,5%, makes the nuts of this species unsuitable for human consumption.

  11. Rangewide analysis of fungal associations in the fully mycoheterotrophic Corallorhiza striata complex (Orchidaceae) reveals extreme specificity on ectomycorrhizal Tomentella (Thelephoraceae) across North America

    Science.gov (United States)

    Craig F. Barrett; John V. Freudenstein; D. Lee Taylor; Urmas. Koljalg

    2010-01-01

    Fully mycoheterotrophic plants offer a fascinating system for studying phylogenetic associations and dynamics of symbiotic specificity between hosts and parasites. These plants frequently parasitize mutualistic mycorrhizal symbioses between fungi and trees. Corallorhiza striata is a fully mycoheterotrophic, North American orchid distributed from...

  12. Philippe Bloch: Reducing distance between experiments and CERN

    CERN Multimedia

    2009-01-01

    With its unique combination of several hundred staff members and thousands of users from around the world sharing offices and physics data and profiting from mutually beneficial exchanges of know-how and expertise, the PH Department is a good example of a successful worldwide collaboration, set up as it was to construct and run the Laboratory’s physics experiments. The PH Depart-ment has always played host to thousands of users that contribute to CERN experiments and work on them, and whose numbers are set to grow in the years to come. With his long-standing experience as a user and then as the head of the CERN group within the CMS collaboration, Philippe Bloch, the new PH Department Head, is in favour of closer links between the Department and the experiments. "I think that the PH management should have a direct link to the experiments, and to do so we are holding regular management team meetings comprising members of the Department’s management and the e...

  13. Haematological studies of climbing perch (Anabas testudineus Bloch

    Directory of Open Access Journals (Sweden)

    Sukasem, N.

    2005-02-01

    Full Text Available Some blood parameters of the climbing perch (Anabas testudineus Bloch i.e. red (RBC and white (WBC blood cell count, percent haematocrit (HTC, hemoglobin, plasma protein as well as hepatosomatic index (HSI were studied. There were no statistically significant difference (p>0.05 in average body weight and length of fish from the earthen pond and net cage culture, which were 16.85±1.46 g and 16.24±2.42 g, respectively, for the weight and 10.02±0.25 and 9.74±0.37 cm, respectively, for the length. Haematologicalstudies revealed that RBC, WBC including percent HTC levels of the fish from earthen pond and net cage were not significantly different (> 0.05. Whereas hemoglobin and serum protein concentration of the fish sampling from net cage were higher than those sampled from the earthen pond (p<0.05, with value of 12.21± 0.91 g/dl and 11.12±0.85 g/dl for hemoglobin and 4.61±0.50 mg/dl and 3.87±0.62 mg/dl for serum protein, respectively. HSI of the fish cultured in the earthen pond was significantly (p<0.05 higher than that of fish reared in net cage, with value of 1.93±0.12% and 1.66±0.12%, respectively.

  14. Phycospheric Native Bacteria Pelagibaca bermudensis and Stappia sp. Ameliorate Biomass Productivity of Tetraselmis striata (KCTC1432BP) in Co-cultivation System through Mutualistic Interaction.

    Science.gov (United States)

    Park, Jungsoo; Park, Bum Soo; Wang, Pengbin; Patidar, Shailesh K; Kim, Jin Ho; Kim, Sae-Hee; Han, Myung-Soo

    2017-01-01

    Effective sustainable algal cultivation techniques are essential for mass production of the marine microalga Tetraselmis for biofuel and array of co-products. The phycospheric communities affect the microalgal growth and metabolism through various allelochemical and nutrient interactions; hence, their potential to affect the quantity and quality of both biomass and bioproducts is significant. In the present study, we have screened the phycospheric communities of biofuel producing Tetraselmis striata (KCTC1432BP). A total of 26 bacterial strains were isolated and identified from the phycosphere of T. striata mass culture. Then, each bacterial strain was tested in co-cultivation conditions with T. striata for evaluating its growth promoting and inhibitory effects. Among these all strains, two promising strains (Pelagibaca bermudensis KCTC 13073BP and Stappia sp. KCTC 13072BP) were selected because of their maximum growth promoting effects and mutualistic interactions. The growth rate, biomass productivity, lipid contents, and fatty acids were analyzed during their combined growth in O3 media and compared with axenic growth of T. striata. Later, growth promoting mechanisms in the co-cultivation environment were investigated for these promising bacterial strains under replete and limited conditions of nutrients (nitrate, phosphate, and vitamin B12). The growth promoting potential of P. bermudensis was illustrated by the two fold enhancement in biomass productivity. These bacteria are promising for microalgal cultivation without any negative effects on the native seawater bacterial communities, as revealed by next generation sequencing analysis. This study represents, to date, the first report highlighting the role of phycospheric growth promoting bacteria of promising biofuel feedstock T. striata.

  15. Comparative effects of Scrophularia striata with synbiotic and antibiotic on performance and immune response of broiler chickens

    Directory of Open Access Journals (Sweden)

    Farhad Rostami

    2015-12-01

    Full Text Available Introduction: Following the ban on antimicrobial growth promoters in poultry nutrition in EU and growing pressure on poultry producers in other parts of the world, there is an increasing interest in searching for growth promoting and immune system-strengthening alternatives. Among the possible alternatives, probiotics, prebiotics, synbiotics (combination of probiotic and prebiotic and more recently phytogenic products are considered interesting because they have acquired more reliability and acceptability among consumers as safe and natural additives. Scrophularia striata (SS is a plant which grows in the northeastern part of Iran and their immunomodulatory activities of some species of Scrophularia have also been reported by other investigators. Due to the lack of study for Scrophularia striata effects on broilers performance, and the importance of improving the immune status of broilers, this study was conducted to evaluate the effect of S. striata on male broilers growth performance, heterophil to lymphocyte ratio and immunity; and also to compare them with virginiamycin as a well-documented antibiotic growth-promoter. Materials and methods: Two-hundred and fifty of one-day-old male (Ross 308 broiler chicks were classified into 25 groups. Each group included 10 chicks (five treatments and five replicates per treatment. The five experimental treatments were as follow: basal diet with no additives (control diet and basal diet containing virginiamycin antibiotic, synbiotic, 0.4 or 0.8 % SS. Feed intake (FI and body weight gain (BWG were recorded in different periods and feed conversion ratio (FCR was calculated. To study the effects of different treatments on blood leukocyte subpopulations, blood samples of two birds from each replicate were collected from the wing vein at the end of experiment. EDTA-containing blood samples were stained subsequently, 100 leukocytes per samples were counted by an optical microscope. The ratio of heterophil (H to

  16. Experimental and theoretical demonstration of acoustic Bloch oscillations in porous silicon structures

    Energy Technology Data Exchange (ETDEWEB)

    Lazcano, Z.; Arriaga, J., E-mail: arriaga@ifuap.buap.mx [Instituto de Física, Benemérita Universidad Autónoma de Puebla, 18 Sur y San Claudio, Edif. 110-A, Ciudad Universitaria, 72570 Puebla (Mexico); Aliev, G. N. [Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom)

    2014-04-21

    We report the theoretical calculations and the experimental demonstration of acoustic Bloch oscillations and Wannier-Stark ladders in linear tilted multilayer structures based on porous silicon. The considered structures consist of layers with constant porosity alternated by layers with a linear gradient in the parameter η=1/v{sub L}{sup 2} along the growth direction in order to tilt the acoustic band gap. The purpose of this gradient is to mimic the tilted electronic miniband structure of a superlattice semiconductor under an external electric field. In this way, acoustic Wannier-Stark ladders of equidistant modes are formed and they were experimentally confirmed in the transmission spectrum around 1.2 GHz. Their frequency separation defines the period of the acoustic Bloch oscillations. We fabricated three different structures with the same thicknesses but different values in the η parameter to observe the effect on the period of the Bloch oscillations. We measured the acoustic transmission spectra in the frequency domain, and by using the Fourier transform, we obtained the transmission in the time domain. The transmission spectra of the fabricated samples show acoustic Bloch oscillations with periods of 27, 24, and 19 ns. The experimental results are in good agreement with the transfer matrix calculations. The observed phenomenon is the acoustic counterpart of the well known electronic Bloch oscillations.

  17. Osteopathia striata congenita with cranial sclerosis and intellectual disability due to contiguous gene deletions involving the WTX locus.

    Science.gov (United States)

    Holman, S K; Morgan, T; Baujat, G; Cormier-Daire, V; Cho, T-J; Lees, M; Samanich, J; Tapon, D; Hove, H D; Hing, A; Hennekam, R; Robertson, S P

    2013-03-01

    Osteopathia striata congenita with cranial sclerosis (OSCS) is a skeletal dysplasia caused by germline deletions of or truncating point mutations in the X-linked gene WTX (FAM123B, AMER1). Females present with longitudinal striations of sclerotic bone along the long axis of long bones and cranial sclerosis, with a high prevalence of cleft palate and hearing loss. Intellectual disability or neurodevelopmental delay is not observed in females with point mutations in WTX leading to OSCS. One female has been described with a deletion spanning multiple neighbouring genes suggesting that deletion of some neighbouring loci may result in abnormal neurodevelopment. In this cohort of 13 females with OSCS resulting from deletions of WTX, a relationship is observed where deletion of ARHGEF9 and/or MTMR8 in conjunction with WTX results in an additional neurodevelopmental phenotype whereas deletion of ASB12 along with WTX is associated with a good neurodevelopmental prognosis. © 2012 John Wiley & Sons A/S.

  18. Paraquat, but not maneb, induces synucleinopathy and tauopathy in striata of mice through inhibition of proteasomal and autophagic pathways.

    Directory of Open Access Journals (Sweden)

    Jonathan Wills

    Full Text Available SNCA and MAPT genes and environmental factors are important risk factors of Parkinson's disease [PD], the second-most common neurodegenerative disease. The agrichemicals maneb and paraquat selectively target dopaminergic neurons, leading to parkinsonism, through ill-defined mechanisms. In the current studies we have analyzed the ability of maneb and paraquat, separately and together, to induce synucleinopathy and tauopathy in wild type mice. Maneb was ineffective in increasing α-synuclein [α-Syn] or p-Tau levels. By contrast, paraquat treatment of mice resulted in robust accumulation of α-Syn and hyperphosphorylation of Tau in striata, through activation of p-GSK-3β, a major Tau kinase. Co-treatment with maneb did not enhance the effects of paraquat. Increased hyperacetylation of α-tubulin was observed in paraquat-treated mice, suggesting cytoskeleton remodeling. Paraquat, but not maneb, inhibited soluble proteasomal activity on a peptide substrate but this was not associated with a decreased expression of 26S proteasome subunits. Both paraquat and maneb treatments increased levels of the autophagy inhibitor, mammalian target of rapamycin, mTOR, suggesting impaired axonal autophagy, despite increases in certain autophagic proteins, such as beclin 1 and Agt12. Autophagic flux was also impaired, as ratios of LC3 II to LC3 I were reduced in treated animals. Increased mTOR was also observed in postmortem human PD striata, where there was a reduction in the LC3 II to LC3 I ratio. Heat shock proteins were either increased or unchanged upon paraquat-treatment suggesting that chaperone-mediated autophagy is not hampered by the agrichemicals. These studies provide novel insight into the mechanisms of action of these agrichemicals, which indicate that paraquat is much more toxic than maneb, via its inhibitory effects on proteasomes and autophagy, which lead to accumulation of α-Syn and p-Tau.

  19. Integral type operators from normal weighted Bloch spaces to QT,S spaces

    Directory of Open Access Journals (Sweden)

    Yongyi GU

    2016-08-01

    Full Text Available Operator theory is an important research content of the analytic function space theory. The discussion of simultaneous operator and function space is an effective way to study operator and function space. Assuming that  is an analytic self map on the unit disk Δ, and the normal weighted bloch space μ-B is a Banach space on the unit disk Δ, defining a composition operator C∶C(f=f on μ-B for all f∈μ-B, integral type operator JhC and CJh are generalized by integral operator and composition operator. The boundeness and compactness of the integral type operator JhC acting from normal weighted Bloch spaces to QT,S spaces are discussed, as well as the boundeness of the integral type operators CJh acting from normal weighted Bloch spaces to QT,S spaces. The related sufficient and necessary conditions are given.

  20. Bloch wave deafness and modal conversion at a phononic crystal boundary

    Directory of Open Access Journals (Sweden)

    Vincent Laude

    2011-12-01

    Full Text Available We investigate modal conversion at the boundary between a homogeneous incident medium and a phononic crystal, with consideration of the impact of symmetry on the excitation of Bloch waves. We give a quantitative criterion for the appearance of deaf Bloch waves, which are antisymmetric with respect to a symmetry axis of the phononic crystal, in the frame of generalized Fresnel formulas for reflection and transmission at the phononic crystal boundary. This criterion is used to index Bloch waves in the complex band structure of the phononic crystal, for directions of incidence along a symmetry axis. We argue that within deaf frequency ranges transmission is multi-exponential, as it is within frequency band gaps.

  1. Observation of Bloch oscillations in complex PT-symmetric photonic lattices

    CERN Document Server

    Wimmer, Martin; Christodoulides, Demetrios; Peschel, Ulf

    2016-01-01

    Light propagation in periodic environments is often associated with a number of interesting and potentially useful processes. If a crystalline optical potential is also linearly ramped, light can undergo periodic Bloch oscillations, a direct outcome of localized Wannier-Stark states and their equidistant eigenvalue spectrum. Even though these effects have been extensively explored in conservative settings, this is by no means the case in non-Hermitian photonic lattices encompassing both amplification and attenuation. Quite recently, Bloch oscillations have been predicted in parity-time-symmetric structures involving gain and loss in a balanced fashion. While in a complex bulk medium, one intuitively expects that light will typically follow the path of highest amplification, in a periodic system this behavior can be substantially altered by the underlying band structure. Here, we report the first experimental observation of Bloch oscillations in parity-time-symmetric mesh lattices. We show that these revivals ...

  2. Shapes displayed with durations in the microsecond range do not obey Bloch's law of temporal summation.

    Science.gov (United States)

    Greene, Ernest; Ogden, R Todd

    2013-01-01

    Shape patterns were displayed with simultaneous brief flashes from a light-emitting diode array. Flash durations in the microsecond range and luminous intensities were adjusted to vary the degree of successful shape recognition. Four experiments were conducted to test whether Bloch's law would apply in this task. Bloch's law holds that for very brief flashes the perceptual threshold is determined by the total number of photons being delivered, i.e., there is reciprocity of intensity and duration. The present results did not find that effectiveness of flashes was based on the total quantity of photons, as predicted by Bloch's law. Additionally, the evidence points to a visual mechanism that has ultra-high temporal precision that either registers the rate of photon flux or the duration of flashes.

  3. Shapes Displayed with Durations in the Microsecond Range Do Not Obey Bloch's Law of Temporal Summation

    Directory of Open Access Journals (Sweden)

    Ernest Greene

    2013-09-01

    Full Text Available Shape patterns were displayed with simultaneous brief flashes from a light-emitting diode array. Flash durations in the microsecond range and luminous intensities were adjusted to vary the degree of successful shape recognition. Four experiments were conducted to test whether Bloch's law would apply in this task. Bloch's law holds that for very brief flashes the perceptual threshold is determined by the total number of photons being delivered, i.e., there is reciprocity of intensity and duration. The present results did not find that effectiveness of flashes was based on the total quantity of photons, as predicted by Bloch's law. Additionally, the evidence points to a visual mechanism that has ultra-high temporal precision that either registers the rate of photon flux or the duration of flashes.

  4. Studies on the epidemiology and histopathology of Euclinostomum heterostomum (Trematoda; Digenea infection in Channa punctata from North India

    Directory of Open Access Journals (Sweden)

    Shareef P. A. Ahammed

    2015-09-01

    Full Text Available A survey on the occurrence and epidemiology of the encysted progenetic metacercariae of Euclinostomum heterostomum infection in Channa punctata in the Aligarh region of North India revealed a mean prevalence, intensity, and abundance of 18.61, 1.52, and 0.38%, respectively, during the period from April 2011 to March 2012. Liver, kidney, peritoneum, muscle, and ovary were found to be infected with this parasite, and the later three are reported for the first time in this fish species. The histopathology of the infected tissues indicated the following at the host-parasite interface: tissue damage, infiltration of immune cells into the cyst wall, chronic inflammatory responses, and granulomatous lesions. The infected liver showed degeneration of hepatocytes, cytoplasmic vacuolation, nuclear alterations, mallory body formation, fibrosis, and necrosis. The pathology of the infected kidney included distortion and dilation of renal tubules, vacuolar degeneration, hypertrophy and hyperplasia of tubular epithelial cells, occlusion of tubules, fibrosis, hemorrhage, and congestion of glomeruli. The infected muscle demonstrated comparatively fewer pathological changes confined only to the circumference of the cyst wall. The ovary displayed the least changes. The conclusions drawn from the study are that the large metacercarial cysts formed by E. heterostomum in the vital organs of the economically important fish C. punctata could result in the impairment of fish physiology and health, thereby affecting their productivity and quality for human consumption.

  5. The Effect of Channa striatus (Haruan Extract on Pain and Wound Healing of Post-Lower Segment Caesarean Section Women

    Directory of Open Access Journals (Sweden)

    Siti Zubaidah Ab Wahab

    2015-01-01

    Full Text Available Channa striatus has been consumed for decades as a remedy to promote wound healing by women during postpartum period. The objectives of this study were to compare postoperative pain, wound healing based on wound evaluation scale (WES, wound cosmetic appearance based on visual analogue scale (VAS scores and patient satisfaction score (PSS, and safety profiles between C. striatus group and placebo group after six weeks of lower segment caesarean section (LSCS delivery. A randomised, double-blind, placebo-controlled study was conducted. Subjects were randomised in a ratio of 1 : 1 into either the C. striatus group (500 mg daily or placebo group (500 mg of maltodextrin daily. 76 subjects were successfully randomised, with 38 in the C. striatus group and 35 in the placebo group. There were no significant differences in postoperative pain p=0.814 and WES p=0.160 between the C. striatus and placebo groups. However, VAS and PSS in the C. striatus group were significantly better compared with the placebo group (p=0.014 and p<0.001, resp.. The safety profiles showed no significant differences between the groups. In conclusion, six-week supplementation of 500 mg of C. striatus extract showed marked differences in wound cosmetic appearance and patient’s satisfaction and is safe for human consumption.

  6. DNA damage and oxidative stress modulatory effects of glyphosate-based herbicide in freshwater fish, Channa punctatus.

    Science.gov (United States)

    Nwani, C D; Nagpure, N S; Kumar, Ravindra; Kushwaha, Basdeo; Lakra, W S

    2013-09-01

    The present study was undertaken to evaluate the genotoxic and oxidative stress modulatory effects of commercial formulation of glyphosate-based herbicide (Roundup(®)) in freshwater fish Channa punctatus. Three sublethal test concentrations of the herbicide viz., SL-I (1/10th of LC50=∼3.25mgL(-1)), SL-II (1/8th of LC50=∼4.07mgL(-1)) and SL-III (1/5th of LC50=∼6.51mgL(-1)) were calculated using 96-LC50 value and the test specimens were exposed to these concentrations. Blood and gill cells of the exposed specimens were sampled on day 1, 7, 14, 21, 28 and 35 to examine the DNA damage using comet assay and to assess the alteration in lipid peroxidation and antioxidant enzymes activities. The highest DNA damage was observed on day 14 at all test concentrations followed by gradual non-linear decline. Induction of oxidative stress in the blood and gill cells were evidenced by increased lipid peroxidation level, while antioxidants namely superoxide dismutase, catalase and glutathione reductase responded in a concentration-dependent manner. The results supported the integrated use of comet and antioxidant assays in determining the toxicity of water pollutants which could be used as part of monitoring programs. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Individual growth and reproductive behavior in a newly established population of northern snakehead (Channa argus), Potomac River, USA

    Science.gov (United States)

    Landis, Andrew M. Gascho; Lapointe, Nicolas W. R.; Angermeier, Paul L.

    2010-01-01

    Northern snakehead (Channa argus) were first found in the Potomac River in 2004. In 2007, we documented feeding and reproductive behavior to better understand how this species is performing in this novel environment. From April to October, we used electrofishing surveys to collect data on growth, condition, and gonad weight of adult fish. Growth rates of young were measured on a daily basis for several weeks. Mean length-at-age for Potomac River northern snakehead was lower than for fish from China, Russia, and Uzbekistan. Fish condition was above average during spring and fall, but below average in summer. Below-average condition corresponded to periods of high spawning activity. Gonadosomatic index indicated that females began spawning at the end of April and continued through August. Peak spawning occurred at the beginning of June when average temperatures reached 26°C. Larval fish growth rate, after the transition to exogenous feeding, was 2.3 (SD ± 0.7) mm (total length, TL) per day. Although Potomac River northern snakehead exhibited lower overall growth rates when compared to other populations, these fish demonstrated plasticity in timing of reproduction and rapid larval growth rates. Such life history characteristics likely contribute to the success of northern snakehead in its new environment and limit managers’ options for significant control of its invasion.

  8. Multiple biomarker responses (serum biochemistry, oxidative stress, genotoxicity and histopathology) in Channa punctatus exposed to heavy metal loaded waste water.

    Science.gov (United States)

    Javed, Mehjbeen; Ahmad, Md Irshad; Usmani, Nazura; Ahmad, Masood

    2017-05-10

    Experiments were conducted to investigate the health of fish Channa punctatus inhabiting heavy metal-loaded waste water. Heavy metals in the order of Fe > Mn > Zn > Co > Ni > Cu = Cr were present in the waste water. Gills had high metal load followed by liver and then kidney. Albumin, albumin to globulin (A:G) ratio, triglyceride, high density lipoprotein (HDL) and very low density lipoprotein (VLDL) were found to be lower but phospholipid, low density lipoprotein (LDL), total protein, lipid and cholesterol were higher as compared to the reference. Oxidative stress markers such as superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST) and lipid peroxidation (LPO) were significantly higher in all tissues, whereas reduced glutathione (GSH) levels were comparatively low. Damage to DNA was observed with significantly higher mean tail length of comets in the exposed fish gill cells (30.9 µm) followed by liver (24.3 µm) and kidney (20.6 µm) as compared to reference fish (5.2, 4.8 and 5.9 µm respectively). Histopathology in gill, liver and kidney also showed marked damage. Integrated biochemical, oxidative stress, genotoxicity and histopathological findings are valuable biomarkers for native fish adaptive patterns, and monitoring of water quality/pollution of freshwater ecosystems.

  9. Epizootic ulcerative syndrome caused by Aphanomyces invadans in captive bullseye snakehead Channa marulius collected from south Florida, USA

    Science.gov (United States)

    Saylor, Ryan K.; Miller, Debra L.; Vandersea, Mark W.; Bevelhimer, Mark S.; Schofield, Pamela J.; Bennett, Wayne A.

    2010-01-01

    Epizootic ulcerative syndrome (EUS) caused by the oomycete Aphanomyces invadans is an invasive, opportunistic disease of both freshwater and estuarine fishes. Originally documented as the cause of mycotic granulomatosis of ornamental fishes in Japan and as the cause of EUS of fishes in southeast Asia and Australia, this pathogen is also present in estuaries and freshwater bodies of the Atlantic and gulf coasts of the USA. We describe a mass mortality event of 343 captive juvenile bullseye snakehead Channa marulius collected from freshwater canals in Miami-Dade County, Florida. Clinical signs appeared within the first 2 d of captivity and included petechiae, ulceration, erratic swimming, and inappetence. Histological examination revealed hyphae invading from the skin lesions deep into the musculature and internal organs. Species identification was confirmed using a species-specific PCR assay. Despite therapeutic attempts, 100% mortality occurred. This represents the first documented case of EUS in bullseye snakehead fish collected from waters in the USA. Future investigation of the distribution and prevalence of A. invadans within the bullseye snakehead range in south Florida may give insight into this pathogen-host system.

  10. Epizootic ulcerative syndrome caused by Aphanomyces invadans in captive bullseye snakehead Channa marulius collected from south Florida, USA

    Energy Technology Data Exchange (ETDEWEB)

    Saylor, Ryan [University of West Florida; Miller, Debra [University of Georgia; Vandersea, Mark [National Oceanic and Atmospheric Admin; Bevelhimer, Mark S [ORNL; Schofield, Pamela [U.S. Geological Survey; Bennett, Wayne [University of West Florida

    2010-02-01

    Epizootic ulcerative syndrome (EUS) caused by the oomycete Aphanomyces invadans is an invasive, opportunistic disease of both freshwater and estuarine fishes. Originally documented as the cause of mycotic granulomatosis of ornamental fishes in Japan and as the cause of EUS of fishes in southeast Asia and Australia, this pathogen is also present in estuaries and freshwater bodies of the Atlantic and gulf coasts of the USA. We describe a mass mortality event of 343 captive juvenile bullseye snakehead Channa marulius collected from freshwater canals in Miami-Dade County, Florida. Clinical signs appeared within the first 2 d of captivity and included petechiae, ulceration, erratic swimming, and inappetence. Histological examination revealed hyphae invading from the skin lesions deep into the musculature and internal organs. Species identification was confirmed using a species-specific PCR assay. Despite therapeutic attempts, 100% mortality occurred. This represents the first documented case of EUS in bullseye snakehead fish collected from waters in the USA. Future investigation of the distribution and prevalence of A. invadans within the bullseye snakehead range in south Florida may give insight into this pathogen-host system.

  11. Photonic Bloch-dipole-Zener Oscillations in Binary Parabolic Optical Waveguide Arrays

    CERN Document Server

    Zheng, Ming Jie; Yu, Kin Wah

    2011-01-01

    We have studied the propagation and Zener tunneling of light in the binary parabolic optical waveguide array (BPOWA), which consists of two evanescently coupled dissimilar optical waveguides. Due to Bragg reflections, BPOWA attains two minibands separated by a minigap at the zone boundary. Various coherent superpositions of optical oscillations and Zener tunneling occur for different parameters on the phase diagram. In particular, Bloch-Zener oscillation and a different type of Bloch-dipole-Zener oscillation are obtained by the field-evolution analysis. The results may have potential applications in optical splitting and waveguiding devices and shed light on the coherent phenomena in optical lattices.

  12. Bloch-wave engineered submicron-diameter quantum-dot micropillars for cavity QED experiments

    DEFF Research Database (Denmark)

    Gregersen, Niels; Lermer, Matthias; Reitzenstein, Stephan

    2013-01-01

    The semiconductor micropillar is attractive for cavity QED experiments. For strong coupling, the figure of merit is proportional to Q/√V, and a design combining a high Q and a low mode volume V is thus desired. However, for the standard submicron diameter design, poor mode matching between the ca...... the cavity and the DBR Bloch mode limits the Q. We present a novel adiabatic design where Bloch-wave engineering is employed to improve the mode matching, allowing the demonstration of a record-high vacuum Rabi splitting of 85 μeV and a Q of 13600 for a 850 nm diameter micropillar....

  13. Generalized Floquet theory: application to dynamical systems with memory and Bloch's theorem for nonlocal potentials.

    Science.gov (United States)

    Traversa, Fabio L; Di Ventra, Massimiliano; Bonani, Fabrizio

    2013-04-26

    Floquet theory is a powerful tool in the analysis of many physical phenomena, and extended to spatial coordinates provides the basis for Bloch's theorem. However, in its original formulation it is limited to linear systems with periodic coefficients. Here, we extend the theory by proving a theorem for the general class of systems including linear operators commuting with the period-shift operator. The present theorem greatly expands the range of applicability of Floquet theory to a multitude of phenomena that were previously inaccessible with this type of analysis, such as dynamical systems with memory. As an important extension, we also prove Bloch's theorem for nonlocal potentials.

  14. Spin-dependent semiconductor Bloch equations: Microscopic theory of Bir-Aronov-Pikus spin relaxation

    Science.gov (United States)

    Lechner, C.; Rössler, U.

    2005-10-01

    Semiconductor Bloch equations, in their extension including the spin degree of freedom of the carriers, are capable to describe spin dynamics on a microscopic level. In the presence of free holes, electron spins can flip simultaneously with hole spins due to electron-hole exchange interaction. This mechanism named after Bir, Aronov, and Pikus is described here by using the extended semiconductor Bloch equations [Phys. Status Solidi B 234, 385 (2002)] and considering carrier-carrier interaction beyond the Hartree-Fock truncation. As a result we derive microscopic expressions for spin-relaxation and spin-dephasing rates.

  15. Cross talk between arsenic and cold on the regulation of inorganic phosphate level in peripheral tissues of fresh water fishes (Channa punctata)

    OpenAIRE

    Haque, Md. Shahidul; Roy, Swapan Kumar

    2013-01-01

    Cold acclimation shows the increased Pi in skeletal muscle of Channa punctata variety of fishes after 1 h and 2 h while reduces at prolonged exposure (4 h). Similar stimulatory effects were observed in heart, however, reduced at 30 min and 4 h and in liver it causes prevention of Pi release after 30 min, 1 h, 2 h and 4 h respectively. In gastrointestinal tract, the effects were pronounced whenever the fishes were exposed to cold for 1 h and 2 h, while reduced activity was demonstrated after 4...

  16. Methanol Extracts Potential of Mas Ngur Shells (Atactodea striata against Protease Profile and Description of Histopathology of Jejunum Rats Exposed by Indomethacin

    Directory of Open Access Journals (Sweden)

    Vivi Shofia

    2015-11-01

    Full Text Available Inflammatory Bowel Disease (IBD is a multi-factorial disorder caused by genetic factors, environmental and immune response. One of the causes of IBD is a side effect of non-steroidal of anti-inflammatory drugs (NSAIDs. Indomethacin is an NSAID that activates macrophages and triggers increasing of protease activity. Mas Ngur shells (Atactodea striata contains an antioxidant that inhibits the protease activity. This research used rats (Rattus norvegicus induced by Indomethacin and treated with methanol extract of Mas Ngur shells (A. striata at doses of 100 and 400 mg/kg of body weight (BW. Therapy potency of the Mas Ngur shells methanol extracts were identified by measuring protease activity and observed the Jejenum histopathology. Statistical analysis showed that the Mas Ngur shells therapy showed significant differences (p <0.05 by decreasing of protease activity and improve jejunum histopathology of IBD induced rats

  17. Computational Modeling of Bloch Surface Waves in One-Dimensional Periodic and Aperiodic Multilayer Structures

    Science.gov (United States)

    Koju, Vijay

    Photonic crystals and their use in exciting Bloch surface waves have received immense attention over the past few decades. This interest is mainly due to their applications in bio-sensing, wave-guiding, and other optical phenomena such as surface field enhanced Raman spectroscopy. Improvement in numerical modeling techniques, state of the art computing resources, and advances in fabrication techniques have also assisted in growing interest in this field. The ability to model photonic crystals computationally has benefited both the theoretical as well as experimental communities. It helps the theoretical physicists in solving complex problems which cannot be solved analytically and helps to acquire useful insights that cannot be obtained otherwise. Experimentalists, on the other hand, can test different variants of their devices by changing device parameters to optimize performance before fabrication. In this dissertation, we develop two commonly used numerical techniques, namely transfer matrix method, and rigorous coupled wave analysis, in C++ and MATLAB, and use two additional software packages, one open-source and another commercial, to model one-dimensional photonic crystals. Different variants of one-dimensional multilayered structures such as perfectly periodic dielectric multilayers, quasicrystals, aperiodic multilayer are modeled, along with one-dimensional photonic crystals with gratings on the top layer. Applications of Bloch surface waves, along with new and novel aperiodic dielectric multilayer structures that support Bloch surface waves are explored in this dissertation. We demonstrate a slow light configuration that makes use of Bloch Surface Waves as an intermediate excitation in a double-prism tunneling configuration. This method is simple compared to the more usual techniques for slowing light using the phenomenon of electromagnetically induced transparency in atomic gases or doped ionic crystals operated at temperatures below 4K. Using a semi

  18. Characterization of Modified Look Locker (MOLLI) using Bloch Simulations and Corroboration with Scan Measurements

    NARCIS (Netherlands)

    Gai, N.D.; Stehning, C.; Nacif, M.; Bluemke, D.

    2012-01-01

    This manuscript shows that Bloch simulations provide a convenient way for predicting response of a modified Look Locker (MOLLI) T1 mapping sequence to various parameters that affect T1 accuracy of the technique. In particular, the effect of T2 on accuracy is shown. Phantom- and first in vivo

  19. The Contributions of Felix Bloch and W. V. Houston to the Electron Theory of Metals

    Science.gov (United States)

    Rorschach, H. E., Jr.

    1970-01-01

    Discusses the contributions of Bloch and Houston to the electron theory of metals. Contains (1) a biographical note on W. V. Houston, (2) a review of the development of the electron theory of metals, and (3) a discussion of gravitationally induced electric fields. Bibliography. (LC)

  20. Bloch oscillations and accelerated Bose–Einstein condensates in an optical lattice

    Energy Technology Data Exchange (ETDEWEB)

    Sacchetti, Andrea, E-mail: andrea.sacchetti@unimore.it

    2017-01-30

    Highlights: • Discrete nonlinear Schrödinger model for accelerated BECs in optical lattices. • Numerical computation of wavefunction BECs dynamics. • Correlation between nonlinearity and the oscillating period of the BEC's center of mass. • Discussion of the validity of the Bloch Theorem for accelerated BECs in an optical lattice. - Abstract: We discuss the method for the measurement of the gravity acceleration g by means of Bloch oscillations of an accelerated BEC in an optical lattice. This method has a theoretical critical point due to the fact that the period of the Bloch oscillations depends, in principle, on the initial shape of the BEC wavepacket. Here, by making use of the nearest-neighbor model for the numerical analysis of the BEC wavefunction, we show that in real experiments the period of the Bloch oscillations does not really depend on the shape of the initial wavepacket and that the relative uncertainty, due to the fact that the initial shape of the wavepacket may be asymmetrical, is smaller than the one due to experimental errors. Furthermore, we also show that the relation between the oscillation period and the scattering length of the BEC's atoms is linear; this fact suggests us a new experimental procedure for the measurement of the scattering length of atoms.

  1. Don Bloch's vision for Collaborative Family Health Care: Progress and next steps.

    Science.gov (United States)

    Peek, C J

    2015-06-01

    Don Bloch is the central figure in the origin story for the field of collaborative family health care; the journal Families, Systems, & Health; and for the Collaborative Family Healthcare Association (CFHA). He exerted extraordinary intellectual and practical leadership for all 3. He convened a national working session in 1994 that took stock of the field and set out next steps, one of which was to create the interprofessional organization dedicated to collaborative family health care that is now CFHA. As part of honoring Don Bloch's contributions to the field and this journal, this article sets out tenets of his original vision and traces next steps toward this vision generated by national groups between 1994 and 2014, showing what is the same or different over these 20 years, and especially what this means for the field going forward. Precepts of Don Bloch's original vision are drawn from his writings, including the briefing papers he prepared for the national Wingspread group convened in 1994, which also set out next steps for the field. These steps are then compared with next developmental steps for the field generated by CFHA conference attendees in 2004 and again in 2014, after reviewing the history of the organization and the field. Much of Don Bloch's vision has remained relevant to health care transformation, with a number of areas showing significant accomplishment and acceptance, whereas others remain aspirational, and a few others arguably being more difficult to achieve now than when Don articulated them. (c) 2015 APA, all rights reserved).

  2. Proof of the extended Bloch-Messiah theorem in the thermal Hartree-Fock-Bogoliubov theory

    Science.gov (United States)

    Tanabe, K.; Sugawara-Tanabe, K.

    1990-09-01

    It is shown that an application of the thermo field dynamics (TFD) to the thermal Hartree-Fock-Bogoliubov (THFB) theory leads to the extended form of the Bloch-Messiah theorem for the finite temperature formalism. The generalized density matrix defined on the enlarged operator space including tilded into account the thermal fluctuation of fermion number for the system under consideration.

  3. Electronic energy band parameters of CsCl evaluated on core Bloch states and plane waves

    Energy Technology Data Exchange (ETDEWEB)

    Syrotyuk, S.V. [Semiconductor Electronics Department, National University ' Lviv Polytechnic' , S. Bandera str. 12, Lviv 79013 (Ukraine); Chornodolskyy, Ya.M. [Physics Department, Ivan Franko National University of Lviv, Kyryla i Mefodiya str. 8, Lviv 79005 (Ukraine)], E-mail: chornodolsky@ukr.net; Stryganyuk, G.B. [HASYLAB at DESY, Notkestr. 85, Hamburg 22607 (Germany); Voloshinovskii, A.S. [Physics Department, Ivan Franko National University of Lviv, Kyryla i Mefodiya str. 8, Lviv 79005 (Ukraine); Rodnyi, P.A. [St. Petersburg State Polytechnical University, Polytekhnicheskaya 29, St. Petersburg 195251 (Russian Federation)

    2007-04-15

    Electronic energy bands of CsCl crystal have been calculated within the mixed basis approach with using the core Bloch states and plane waves. The calculated energy parameters of the crystal are in the satisfactory agreement with the experimental data obtained from the analysis of the core-valence luminescence spectra. The obtained results form a base for calculation of CVL spectra parameters.

  4. Beam splitter and combiner based on Bloch oscillations in spatially modulated waveguide arrays

    CERN Document Server

    Zhang, Yiqi; Zhong, Weiping; Wen, Feng; Guo, Yang; Guo, Yao; Lu, Keqing; Zhang, Yanpeng

    2014-01-01

    We numerically investigate the light beam propagation in periodic waveguide arrays which are elaborately modulated with certain structures. We find that the light beam may split, coalesce, deflect, and be localized during propagation in these spatially modulated waveguide arrays. All the phenomena originate from Bloch oscillations, and supply possible method for fabricating on-chip beam splitters and beam combiners.

  5. Populating the Large-Wavevector Realm: Bloch Volume Plasmon Polaritons in Hyperbolic and Extremely Anisotropic Metamaterials

    DEFF Research Database (Denmark)

    Zhukovsky, Sergei; Babicheva, Viktoriia; Orlov, A. A.

    2014-01-01

    Optics of hyperbolic metamaterials is revisited in terms of large-wavevector waves, evanescent in isotropic media but propagating in presence of extreme anisotropy. Identifying the physical nature of these waves as Bloch volume plasmon polaritons, we derive their existence conditions and outline...

  6. Purification, characterization and cDNA cloning of a trypsin from the hepatopancreas of snakehead (Channa argus).

    Science.gov (United States)

    Zhou, Long-Zhen; Ruan, Mi-Mi; Cai, Qiu-Feng; Liu, Guang-Ming; Sun, Le-Chang; Su, Wen-Jin; Cao, Min-Jie

    2012-03-01

    A trypsin was purified from the hepatopancreas of snakehead (Channa argus) by ammonium sulfate fractionation and a series of column chromatographies including DEAE-Sepharose, Sephacryl S-200 HR and Hi-Trap Capto-Q. The molecular mass of the purified trypsin was about 22 kDa, as estimated by SDS-PAGE. The optimum pH and temperature of the purified trypsin were 9.0 and 40°C, respectively. The trypsin was stable in the pH range of 7.5-9.5 and below 45°C. The enzymatic activity was strongly inhibited by serine proteinase inhibitors, such as MBTI, Pefabloc SC, PMSF, LBTI and benzamidine. Peptide mass fingerprinting (PMF) of the purified protein obtained 2 peptide fragments with 25 amino acid residues and were 100% identical to the trypsinogen from pufferfish (Takifugu rubripes). The activation energy (Ea) of this enzyme was 24.65 kJ·M(-1). Apparent K(m) was 1.02 μM and k(cat) was 148 S(-1) for fluorogenic substrate Boc-Phe-Ser-Arg-MCA. A trypsinogen gene encoding 247 amino acid residues was further cloned on the basis of the sequence obtained from PMF and the conserved site peptide of trypsinogen together with 5'-RACE and 3'-RACE. The deduced amino acid sequence contains a signal peptide of 15 residues and an activation peptide of 9 amino acid residues with a mature protein of 223 residues. The catalytic triad His-64, Asp-107, Ser-201 and 12 Cys residues which may form 6 disulfide bonds were conserved. Compared with the PMF data, only 2 amino acid residues difference were identified, suggesting the cloned trypsinogen is quite possibly the precursor of the purified trypsin. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Studies on biomarkers of oxidative stress and associated genotoxicity and histopathology in Channa punctatus from heavy metal polluted canal.

    Science.gov (United States)

    Javed, Mehjbeen; Ahmad, Irshad; Usmani, Nazura; Ahmad, Masood

    2016-05-01

    Some investigations were made on the Satha canal water and health of dwelling fish Channa punctatus at Satha village, district Aligarh (U.P). Metal bioaccumulation and induction of biomarkers such as lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST), reduced glutathione (GSH), DNA damage and histopathology are potential indicators of stress in C. punctatus exposed to effluents. In canal water Cr, Mn, Fe and Ni concentrations were exceeding the permissible limits set by both Bureau of Indian standards (BIS) and WHO. Fe (74%) was highly bioavailable and accumulated in all organs (gill, liver, kidney, muscle and integument). The highest metal pollution index (MPI) value of 53 was observed in gills and the lowest 6 in liver tissue. SOD and LPO were significantly higher in all tissues, whereas CAT, GST and GSH levels declined significantly compared to fish from the reference site. Concomitant damage to DNA was observed with significantly higher mean tail length in the exposed fish gill cells (19 μm) and in liver (12.7 μm) compared to reference fish (5 and 4 μm respectively). Histopathology in gill and liver also show significant damage. Therefore, it can be concluded that the sugar mill effluent has the potential to cause oxidative stress, DNA damage and histopathology in C. punctatus. This canal is a prime source of water and fish food to the local residents of the area. Therefore, the consumers may suffer adverse health effects like that in indicator organism. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Hierarchical demographic approaches for assessing invasion dynamics of non-indigenous species: An example using northern snakehead (Channa argus)

    Science.gov (United States)

    Jiao, Y.; Lapointe, N.W.R.; Angermeier, P.L.; Murphy, B.R.

    2009-01-01

    Models of species' demographic features are commonly used to understand population dynamics and inform management tactics. Hierarchical demographic models are ideal for the assessment of non-indigenous species because our knowledge of non-indigenous populations is usually limited, data on demographic traits often come from a species' native range, these traits vary among populations, and traits are likely to vary considerably over time as species adapt to new environments. Hierarchical models readily incorporate this spatiotemporal variation in species' demographic traits by representing demographic parameters as multi-level hierarchies. As is done for traditional non-hierarchical matrix models, sensitivity and elasticity analyses are used to evaluate the contributions of different life stages and parameters to estimates of population growth rate. We applied a hierarchical model to northern snakehead (Channa argus), a fish currently invading the eastern United States. We used a Monte Carlo approach to simulate uncertainties in the sensitivity and elasticity analyses and to project future population persistence under selected management tactics. We gathered key biological information on northern snakehead natural mortality, maturity and recruitment in its native Asian environment. We compared the model performance with and without hierarchy of parameters. Our results suggest that ignoring the hierarchy of parameters in demographic models may result in poor estimates of population size and growth and may lead to erroneous management advice. In our case, the hierarchy used multi-level distributions to simulate the heterogeneity of demographic parameters across different locations or situations. The probability that the northern snakehead population will increase and harm the native fauna is considerable. Our elasticity and prognostic analyses showed that intensive control efforts immediately prior to spawning and/or juvenile-dispersal periods would be more effective

  9. Haematological changes in South Indian fresh water murrel, Channa punctatus have both EUS and A. hydrophila infection.

    Science.gov (United States)

    Podeti, Koteshwar Rao; Benarjee, G

    2017-06-01

    The mixed infection in fishes is a common feature and in this Pathogens like Bacteria, Fungi and Protozoan's are found together to cause ill health to the fishes known as Epizootic Ulcerative Syndrome (EUS). In this syndrome the low temperature and aquatic pollution aggravates the infection in fishes. In the present study the fresh water edible fish, Channa punctatus (Murrel) was found infected with the bacteria namely, Aeromonas hydrophila, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella salmonicida. The fungi, Aphanomyces invadans was also found. The major objective of this study is to understand the microbial intensity in various organs of fish and hematological variations in both control and EUS infected fish. The highest microbial load of 8.2 ± 0.12 × 107 cfu g-1was observed in the skin where as the lowest load of 3.2 ± 0.8 × 103 cfu g-1 was found in the pancreas. From the microbial diagnosis, A. hydrophila has been isolated from different organs indicating its predominant presence. In comparison with the control the haemotological indices like WBC, MCV, Lymophocytes, Eosinophils and Basophils were found increased in the infected by (17 %), (16 %), (5 %), (58 %) and (27 %) respectively. The variations in microbial load found in fish in the study can be attributed to feeding habits, behavior, fish adaptations among the different fish species. These conditions are being caused by the presence of environmental pollution and are high in heavy native fishes. Thus the results showed that low of Haemoglobin value Packed Cell Volume and Red Blood Corpuscles indicated the presence of anemic conditions in the EUS infected fish found in Warangal.

  10. Anti-inflammatory and antinociceptive effects of Sterculia striata A. St.-Hil. & Naudin (Malvaceae) in rodents.

    Science.gov (United States)

    Silva, Francilene V; Oliveira, Irisdalva S; Figueiredo, Kayo A; Júnior, Francisco B Melo; Costa, Danielly A; Chaves, Mariana H; Amaral, Maurício P M; Almeida, Fernanda R C; Oliveira, Francisco A; Oliveira, Rita C M

    2014-06-01

    The present work reports the anti-inflammatory and antinociceptive activities of the ethanol extract obtained from the stem bark of Sterculia striata A. St.-Hil. & Naudin (Ss-EtOH) in the experimental models of edema induced by carrageenan, dextran, or histamin and nociception induced by chemical stimuli, such as acetic acid, formalin, capsaicin, or glutamate. The Ss-EtOH (50 mg/kg) promoted a marked inhibition on the hind paw edema induced by carrageenan or dextran (30% and 73%, respectively). Besides, Ss-EtOH (25 mg/kg) exhibited a slight activity (30%) on the hind paw edema induced by histamin. The Ss-EtOH (12.5 and 25 mg/kg) showed the antinociceptive activity on chemical stimuli induced by acetic acid (65.59% and 38.37%, respectively), formalin, in the initial (35.08% and 31.5%, respectively) and late phases (44.09% and 83.57%, respectively), capsaicin (43.77% and 51.31%, respectively), or glutamate (36.6% and 52.12%, respectively). Regarding the possible mechanism involved in the antinociceptive effect, Ss-EtOH (12.5 mg/kg) showed a decrease in the antinociceptive effect (65.8%) in the acetic acid model after pretreatment with naloxone. Thus, opioid mechanisms might be underlying this response.

  11. Comprehensive solutions to the Bloch equations and dynamical models for open two-level systems

    Science.gov (United States)

    Skinner, Thomas E.

    2018-01-01

    The Bloch equation and its variants constitute the fundamental dynamical model for arbitrary two-level systems. Many important processes, including those in more complicated systems, can be modeled and understood through the two-level approximation. It is therefore of widespread relevance, especially as it relates to understanding dissipative processes in current cutting-edge applications of quantum mechanics. Although the Bloch equation has been the subject of considerable analysis in the 70 years since its inception, there is still, perhaps surprisingly, significant work that can be done. This paper extends the scope of previous analyses. It provides a framework for more fully understanding the dynamics of dissipative two-level systems. A solution is derived that is compact, tractable, and completely general, in contrast to previous results. Any solution of the Bloch equation depends on three roots of a cubic polynomial that are crucial to the time dependence of the system. The roots are typically only sketched out qualitatively, with no indication of their dependence on the physical parameters of the problem. Degenerate roots, which modify the solutions, have been ignored altogether. Here the roots are obtained explicitly in terms of a single real-valued root that is expressed as a simple function of the system parameters. For the conventional Bloch equation, a simple graphical representation of this root is presented that makes evident the explicit time dependence of the system for each point in the parameter space. Several intuitive, visual models of system dynamics are developed. A Euclidean coordinate system is identified in which any generalized Bloch equation is separable, i.e., the sum of commuting rotation and relaxation operators. The time evolution in this frame is simply a rotation followed by relaxation at modified rates that play a role similar to the standard longitudinal and transverse rates. These rates are functions of the applied field, which

  12. Total phenolic content and in-vitro antioxidant activities from methanolic extract of alligator pipefish, Syngnathoides biaculeatus (Bloch, 1785)

    Digital Repository Service at National Institute of Oceanography (India)

    Sanaye, S.V.; Pise, N.M.; Pawar, A.P.; Parab, P.P.; Sreepada, R.A.; Pawar, H.B.; Murugan, A.

    Alligator pipefish, Syngnathoides biaculeatus (Bloch, 1785) is one of the heavily traded and expensive ingredient in traditional Chinese medicines and there were no reports on its antioxidant activities Total phenolic content (TPC) and in...

  13. Magneto-optical switching of Bloch surface waves in magnetophotonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Romodina, M.N.; Soboleva, I.V.; Fedyanin, A.A., E-mail: fedyanin@nanolab.phys.msu.ru

    2016-10-01

    Bloch-surface-wave (BSW) excitation controlled by Faraday rotation in one-dimensional magnetophotonic crystals is presented. Dispersion curves of the Bloch surface wave and waveguide modes of magnetophotonic crystals consisting of silicon dioxide and bismuth-substituted yttrium-iron-garnet (Bi:YIG) quarter-wavelength-thick layers are calculated using Berreman's 4×4 transfer matrix method. Enhanced Faraday rotation observed in the magnetophotonic crystals in the spectral vicinity of the BSW resonance enables the magneto-optical switching of BSWs. The excitation of the BSWs at the magnetophotonic crystal surface for p-polarized incident light is induced by magneto-optical activity in the Bi:YIG layers.

  14. Nanoscale switch for vortex polarization mediated by Bloch core formation in magnetic hybrid systems

    Science.gov (United States)

    Wohlhüter, Phillip; Bryan, Matthew Thomas; Warnicke, Peter; Gliga, Sebastian; Stevenson, Stephanie Elizabeth; Heldt, Georg; Saharan, Lalita; Suszka, Anna Kinga; Moutafis, Christoforos; Chopdekar, Rajesh Vilas; Raabe, Jörg; Thomson, Thomas; Hrkac, Gino; Heyderman, Laura Jane

    2015-01-01

    Vortices are fundamental magnetic topological structures characterized by a curling magnetization around a highly stable nanometric core. The control of the polarization of this core and its gyration is key to the utilization of vortices in technological applications. So far polarization control has been achieved in single-material structures using magnetic fields, spin-polarized currents or spin waves. Here we demonstrate local control of the vortex core orientation in hybrid structures where the vortex in an in-plane Permalloy film coexists with out-of-plane maze domains in a Co/Pd multilayer. The vortex core reverses its polarization on crossing a maze domain boundary. This reversal is mediated by a pair of magnetic singularities, known as Bloch points, and leads to the transient formation of a three-dimensional magnetization structure: a Bloch core. The interaction between vortex and domain wall thus acts as a nanoscale switch for the vortex core polarization. PMID:26238042

  15. Quantum Theory of Conducting Matter Newtonian Equations of Motion for a Bloch Electron

    CERN Document Server

    Fujita, Shigeji

    2007-01-01

    Quantum Theory of Conducting Matter: Newtonian Equations of Motion for a Bloch Electron targets scientists, researchers and graduate-level students focused on experimentation in the fields of physics, chemistry, electrical engineering, and material sciences. It is important that the reader have an understanding of dynamics, quantum mechanics, thermodynamics, statistical mechanics, electromagnetism and solid-state physics. Many worked-out problems are included in the book to aid the reader's comprehension of the subject. The Bloch electron (wave packet) moves by following the Newtonian equation of motion. Under an applied magnetic field B the electron circulates around the field B counterclockwise or clockwise depending on the curvature of the Fermi surface. The signs of the Hall coefficient and the Seebeck coefficient are known to give the sign of the major carrier charge. For alkali metals, both are negative, indicating that the carriers are "electrons." These features arise from the Fermi surface difference...

  16. Modeling Dzyaloshinskii-Moriya Interaction at Transition Metal Interfaces: Constrained Moment versus Generalized Bloch Theorem

    KAUST Repository

    Dong, Yao-Jun

    2017-10-29

    Dzyaloshinskii-Moriya interaction (DMI) at Pt/Co interfaces is investigated theoretically using two different first principles methods. The first one uses the constrained moment method to build a spin spiral in real space, while the second method uses the generalized Bloch theorem approach to construct a spin spiral in reciprocal space. We show that although the two methods produce an overall similar total DMI energy, the dependence of DMI as a function of the spin spiral wavelength is dramatically different. We suggest that long-range magnetic interactions, that determine itinerant magnetism in transition metals, are responsible for this discrepancy. We conclude that the generalized Bloch theorem approach is more adapted to model DMI in transition metal systems, where magnetism is delocalized, while the constrained moment approach is mostly applicable to weak or insulating magnets, where magnetism is localized.

  17. An optimum Hamiltonian for non-Hermitian quantum evolution and the complex Bloch sphere

    Energy Technology Data Exchange (ETDEWEB)

    Nesterov, Alexander I., E-mail: nesterov@cencar.udg.m [Departamento de Fisica, CUCEI, Universidad de Guadalajara, Av. Revolucion 1500, Guadalajara, CP 44420, Jalisco (Mexico)

    2009-09-28

    For a quantum system governed by a non-Hermitian Hamiltonian, we studied the problem of obtaining an optimum Hamiltonian that generates nonunitary transformations of a given initial state into a certain final state in the smallest time tau. The analysis is based on the relationship between the states of the two-dimensional subspace of the Hilbert space spanned by the initial and final states and the points of the two-dimensional complex Bloch sphere.

  18. Reflectors and resonators for high-k bulk Bloch plasmonic waves in multilayer hyperbolic metamaterials

    DEFF Research Database (Denmark)

    Zhukovsky, Sergei; Lavrinenko, Andrei

    2012-01-01

    We propose proof-of-concept designs of Bragg reflectors and Fabry-Pe´rot resonators for large wave vector waves (Bloch bulk plasmon polaritons) in multilayer metal-dielectric hyperbolic metamaterials. The designs are based on hybrid multilayers having both subwavelength and wavelength......-scale structuring. This multiscale approach is shown to be a promising platform for using bulk plasmonic waves in complex multilayer metamaterials as a new kind of information carriers....

  19. Norm equivalence and composition operators between Bloch/Lipschitz spaces of the ball

    Directory of Open Access Journals (Sweden)

    Stević Stevo

    2006-01-01

    Full Text Available For , let and denote, respectively, the -Bloch and holomorphic -Lipschitz spaces of the open unit ball in . It is known that and are equal as sets when . We prove that these spaces are additionally norm-equivalent, thus extending known results for and the polydisk. As an application, we generalize work by Madigan on the disk by investigating boundedness of the composition operator from to .

  20. Dietary supplementation of Zeolite on growth performance, immunological role, and disease resistance in Channa striatus against Aphanomyces invadans.

    Science.gov (United States)

    Jawahar, Suntharam; Nafar, Adil; Vasanth, Krishnan; Musthafa, Mohamed Saiyad; Arockiaraj, Jesu; Balasundaram, Chellam; Harikrishnan, Ramasamy

    2016-04-01

    Epizootic Ulcerative Syndrome (EUS) caused by Aphanomyces invadans which is a primary fungal parasitic pathogen, inflicts serious economic loss in tropical freshwater fish including snakehead murrel, Channa striatus. In the present study with an aim to circumvent the adverse effects of the traditional measures in graded levels (2%, 4%, and 6%) of Zeolite enriched diet on growth performance, hematology, immunological response, and disease resistance in C. striatus against A. invadans is reported. The final weight (FW), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER), and average daily gain (ADG) were significantly high in infected fish fed with 4% or 6% Zeolite incorporated diets on 4th week. The maximum survival rates (SR) of 96% and 98% were observed when fed with 2% or 4% diets on 4th week. Similarly, the white blood cell (WBC), red blood cell (RBC), hematocrit (Hct), mean corpuscular volume (MCV), and mean corpuscular haemoglobin concentration (MCHC) were significantly high when fed with any Zeolite enriched diet. However, the haemoglobin (Hb) and mean corpuscular haemoglobin (MCH) were significantly high with 4% and 6% Zeolite diets. The total protein and globulin were significantly high with 4% and 6% diets; the albumin, glucose, cholesterol, and triglyceride were significantly elevated with any enriched diet. The 4% and 6% Zeolite diets significantly enhanced the phagocytic activity on 2nd week but the 2% diet could increase it on 4th week. The respiratory burst (RB) activity, complement activity, and lymphocyte proliferation level were significantly enhanced with 4% and 6% Zeolite diets on weeks 1 and 2 while with 2% diet on 4th week. All enriched diets significantly increased the lysozyme activity during the experimental period. Superoxide anion (SOA) production significantly enhanced with 6% diet on weeks 1 and 2 whereas with 2% diet on week 4. Lower cumulative mortality of 10% and 15% was found with 4% and 6

  1. Real-time protein aggregation monitoring with a Bloch surface wave-based approach

    Science.gov (United States)

    Santi, Sara; Barakat, Elsie; Descrovi, Emiliano; Neier, Reinhard; Herzig, Hans Peter

    2014-05-01

    The misfolding and aggregation of amyloid proteins has been associated with incurable diseases such as Alzheimer's or Parkinson's disease. In the specific case of Alzheimer's disease, recent studies have shown that cell toxicity is caused by soluble oligomeric forms of aggregates appearing in the early stages of aggregation, rather than by insoluble fibrils. Research on new strategies of diagnosis is imperative to detect the disease prior to the onset of clinical symptoms. Here, we propose the use of an optical method for protein aggregation dynamic studies using a Bloch surface wave based approach. A one dimension photonic crystal made of a periodic stack of silicon oxide and silicon nitride layers is used to excite a Bloch surface wave, which is sensitive to variation of the refractive index of an aqueous solution. The aim is to detect the early dynamic events of protein aggregation and fibrillogenesis of the amyloid-beta peptide Aβ42, which plays a central role in the onset of the Alzheimer's disease. The detection principle relies on the refractive index changes caused by the depletion of the Aβ42 monomer concentration during oligomerization and fibrillization. We demonstrate the efficacy of the Bloch surface wave approach by monitoring in real-time the first crucial steps of Aβ42 oligomerization.

  2. Coherent amplification and noise in gain-enhanced nanoplasmonic metamaterials: a Maxwell-Bloch Langevin approach.

    Science.gov (United States)

    Pusch, Andreas; Wuestner, Sebastian; Hamm, Joachim M; Tsakmakidis, Kosmas L; Hess, Ortwin

    2012-03-27

    Nanoplasmonic metamaterials are an exciting new class of engineered media that promise a range of important applications, such as subwavelength focusing, cloaking, and slowing/stopping of light. At optical frequencies, using gain to overcome potentially not insignificant losses has recently emerged as a viable solution to ultra-low-loss operation that may lead to next-generation active metamaterials. Maxwell-Bloch models for active nanoplasmonic metamaterials are able to describe the coherent spatiotemporal and nonlinear gain-plasmon dynamics. Here, we extend the Maxwell-Bloch theory to a Maxwell-Bloch Langevin approach-a spatially resolved model that describes the light field and noise dynamics in gain-enhanced nanoplasmonic structures. Using the example of an optically pumped nanofishnet metamaterial with an embedded laser dye (four-level) medium exhibiting a negative refractive index, we demonstrate the transition from loss-compensation to amplification and to nanolasing. We observe ultrafast relaxation oscillations of the bright negative-index mode with frequencies just below the THz regime. The influence of noise on mode competition and the onset and magnitude of the relaxation oscillations is elucidated, and the dynamics and spectra of the emitted light indicate that coherent amplification and lasing are maintained even in the presence of noise and amplified spontaneous emission. © 2012 American Chemical Society

  3. Adele Bloch-Bauer (1881-1925): Possible diagnoses for Gustav Klimt's Lady in Gold.

    Science.gov (United States)

    da Mota, Licia Maria H; Neubarth, Fernando; de Carvalho, Jozélio F; Diniz, Leonardo R; Aires, Rodrigo B; Dos Santos-Neto, Leopoldo L

    2016-08-01

    One of the most famous works by the Austrian symbolist painter Gustav Klimt and one of the most widely reproduced works of art worldwide, Adele Bloch-Bauer I which portrays the beautiful wife of Austrian magnate Ferdinand Bloch-Bauer. Adele was the only woman painted by Klimt on more than one occasion. Apart from the beauty and value of the painting, the daring sea of gold that surrounds Adele and the gentle intimacy with which her fragile figure is portrayed have shrouded the history of this painting in mystery. Beyond speculation as to a special bond between artist and model, observation of the painting with a keener, clinical gaze yields evidence of potential illness in the model: facial erythema which, if not produced artificially by makeup, could represent a malar rash; pallor or cyanosis of the hands; and her draped fingers, which seemingly attempt to hide a deformity. This paper seeks to provide a biographical review both of the painter, Gustav Klimt, and of the subject, Adele Bloch-Bauer; to analyse Klimt's two portrayals of her in a search for evidence of a potential intimate relationship between artist and muse and, finally, to compile clinical evidence of possible diagnoses for the Lady in Gold. © The Author(s) 2016.

  4. Uropygial gland volatiles may code for olfactory information about sex, individual, and species in Bengalese finches Lonchura striata

    Directory of Open Access Journals (Sweden)

    Jian-Xu ZHANG et al.

    2009-10-01

    Full Text Available Over-shadowed by eye-catching vocal and visual signals, chemical communication has long been overlooked in birds. This study aimed at exploring whether volatile composition of the uropygial gland secretion (UGS of birds was associated with the information about sex, individual and species. By using dichloromethane extraction and gas chromatography-mass spectrometry (GC-MS, we analyzed the UGS volatiles of domesticated Bengalese finches (Lonchura striata, Estrildiea which is also known as white-rumped munias. We characterized 16 volatile molecules from the UGS, including eight n-alkanols, five diesters, an ester, an aldehyde and a fatty acid, and quantified them in terms of GC peak area percentages (relative abundances. Among these compounds, hexadecanol and octadecanol were major components in both sexes. The former was richer in males than females and the latter richer in females than males, suggesting that they might be male and female pheromone candidates, respectively. The high inter-individual variations, in relative abundance, of the UGS volatiles implied that they might carry information about individuality. The similarity between GC profiles of the UGS and wing feather from same individuals indicates that the birds might preen the secretion to their feathers to transmit chemical cues. Additionally, by comparing with three sympatric passerine species,i.e., zebra finches Taeniopygia guttata, yellow-bowed buntings Emberiza chrysophrys and rooks Corvus frugilegus, we found that the composition of C13-C18 alkanols in the UGS might contain information about species. Our study also show that quantitative differences (degree of same UGS volatiles might be the key for the Bengalese finch to code for information about sex and individuality whereas both the kind and degree of UGS constituents could be utilized to code for information about species [Current Zoology 55 (5:–2009].

  5. Antioxidant, antityrosinase and antitumor activity comparison: the potential utilization of fibrous root part of Bletilla striata (Thunb. Reichb.f.

    Directory of Open Access Journals (Sweden)

    Fusheng Jiang

    Full Text Available This study was carried out to evaluate the utilization probability of the fibrous root part (FRP of Bletilla striata, which was usually discarded and harvesting pseudobulb part (PSP. The chemical composition, total phenolic content, DPPH radical scavenging activity, Ferric-reducing antioxidant power and tyrosinase inhibition activity were compared between FRP and PSP. Antioxidant and pro-oxidant effect as well as antitumor effect of the extract of FRP and PSP were analyzed by in vitro cell system as well. Thin layer chromatography and high performance liquid chromatography analysis indicated that the chemical compositions in the two parts were similar, but the content in FRP was much higher than PSP. Meanwhile, the FRP extracts showed higher phenolic content, stronger DPPH scavenging activity, Ferric-reducing antioxidant capacity and tyrosinase inhibition activity. Sub-fraction analysis revealed that the distribution characteristic of phenolic components and other active constituents in FRP and PSP were consistent, and mainly deposited in chloroform and acetoacetate fractions. Especially, the chloroform sub-fraction (sch of FRP showed extraordinary DPPH scavenging activity and tyrosinase inhibition activity, with IC50 0.848 mg/L and 4.3 mg/L, respectively. Besides, tyrosinase inhibition activity was even stronger than the positive compound arbutin (31.8 mg/L. Moreover, In vitro cell system analysis confirmed that FRP extract exerts comparable activity with PSP, especially, the sub-fraction sch of FRP showed better antioxidant activity at low dosage and stronger per-oxidant activity at high dosage, and both sch of FRP and PSP can dose-dependent induce HepG2 cells apoptosis, which implied tumor therapeutic effect. Considering that an additional 0.3 kg FRP would be obtained when producing 1.0 kg PSP, our work demonstrated that FRP is very potential to be used together with PSP.

  6. In vitro Effect of Aqueous and Ethanolic Extracts of Scrophularia striata on Some Respiratory and Urinary Bacterial Pathogens

    Directory of Open Access Journals (Sweden)

    Naghmeh Moori Bakhtiari

    2016-01-01

    Full Text Available Background & objectives: History of medicinal plants in healing the pains goes back to five thousand years ago. In addition, strong antibacterial properties have been observed in many of these plants. In this research, the effect of aqueous and ethanolic extracts and also homogenized form of scrophularia striata was examined on some respiratory and urogenital tract bacterial pathogens. Methods: At first, bacterial isolates susceptibility test was done by kerby-bauer disc diffusion method and positive control was determined for every isolate. Then, several dilutions (1000, 500, 250, 125, 62.5 mg/ml of aqueous, ethanolic and homogenized extracts were prepared in distilled water separately. Thirty microliter of each diluted extract was inoculated on sterile blank disc and minimum inhibitory concentration was examined for every studied bacteria by E-test. Minimum inhibitory and bactericidal concentration of extracts was determined by macrodilution method. Results: Based on the results, smaller inhibitory zone than inhibitory zone of positive control was observed only with high concentration of aqueous extract in mannheimia haemolytica and with serial dilutions of ethanolic and homogenized extract in trueperella pyogenes, and with homogenized form in corynebacterium renale. No response was observed with other bacteria. Ethanolic extract showed bactericidal property with 62.5 mg/ml concentration and bacteriostatic property with 125 mg/ml concentration on mannheimia haemolytica which was similar to effect of this extract and homogenized form on trueperella pyogenes. Conclusion: According to the results of this study and common application of this plant in respiratory and urogenital tract infections treatment, study on the role of different bacteria in this infections or effect of this extract on immune system stimulation can be recommended

  7. Nonhost status of commercial Persea americana 'Hass' to Anastrepha ludens, Anastrepha obliqua, Anastrepha serpentina, and Anastrepha striata (Diptera: Tephritidae) in Mexico.

    Science.gov (United States)

    Aluja, Martín; Díaz-Fleischer, Francisco; Arredondo, José

    2004-04-01

    The objective of this study was to determine the host status in Mexico of commercially cultivated and marketed avocado, Persea americana (Mill.), 'Hass' to Anastrepha ludens (Loew), Anastrepha obliqua (Macquart), Anastrepha serpentina (Wiedemann), and Anastrepha striata (Schiner) (Diptera: Tephritidae). Experiments in Michoacán, Mexico, were carried out in six orchards located at three altitudes above sea level during two times (August-October 2001 and April-June 2002). They included choice ('Hass' avocado plus natural host) and no-choice foraging behavior tests on trees under field cages; no-choice, forced infestation trials on caged, fruit-bearing branches in the field, and with individual fruit under laboratory conditions; infestation trials using 'Hass' avocados left unprotected over 1 and 7 d on the ground of orchards; studies to ascertain depth of oviposition and determine egg hatchability; and experiments to determine susceptibility by using time elapsed since removal of fruit from tree as the experimental variable. We trapped adult Anastrepha (n = 7,936) in all orchards and dissected fruit (n = 7,695) from orchards and packing houses (n = 1,620) in search of eggs or larvae. Most (96.7%) A. ludens, A. obliqua, A. striata, and A. serpentina adults were captured in low-elevation orchards. No eggs or larvae were detected in any of the fruit from foraging behavior studies or dissected fruit from orchards or packing houses. Of 5,200 mature, intact fruit on trees in the field forcibly exposed to no-choice female oviposition activity (five females/fruit), we only found four fruit infested by A. ludens but no adults emerged. 'Hass' avocados only became marginally susceptible to attack by A. ludens (but not A. obliqua, A. serpentina, and A. striata) 24 h after being removed from the tree. Fruit placed on the ground in orchards (n = 3,600) were occasionally infested by Neosilba batesi (Curran) (Diptera: Lonchaeidae), a decomposer, but not Anastrepha spp. Based on our

  8. Bloch oscillations of ultracold atoms and measurement of the fine structure constant; Oscillations de Bloch d'atomes ultrafroids et mesure de la constante de structure fine

    Energy Technology Data Exchange (ETDEWEB)

    Clade, P

    2005-10-15

    From a measurement of the recoil velocity of an atom absorbing a photon, it is possible to deduce a determination of the ratio h/m between the Planck constant and the mass of the atoms and then to deduce a value of the fine structure constant alpha. To do this measurement, we use the technique of Bloch oscillations, which allows us to transfer a large number of recoils to atoms. A velocity sensor, based on velocity selective Raman transition, enables us to measure the momentum transferred to the atoms. A measurement with a statistical uncertainty of 4.4 10{sup -9}, in conjunction with a careful study of systematic effects (5 10{sup -9}), has led us to a determination of alpha with an uncertainty of 6.7 10{sup -9}: {alpha}{sup -1}(Rb) = 137.03599878 (91). This uncertainty is similar to the uncertainty of the best determinations of alpha based on atom interferometry. (author)

  9. Adenosine A(2A receptors measured with [C]TMSX PET in the striata of Parkinson's disease patients.

    Directory of Open Access Journals (Sweden)

    Masahiro Mishina

    Full Text Available Adenosine A(2A receptors (A2ARs are thought to interact negatively with the dopamine D(2 receptor (D2R, so selective A2AR antagonists have attracted attention as novel treatments for Parkinson's disease (PD. However, no information about the receptor in living patients with PD is available. The purpose of this study was to investigate the relationship between A2ARs and the dopaminergic system in the striata of drug-naïve PD patients and PD patients with dyskinesia, and alteration of these receptors after antiparkinsonian therapy. We measured binding ability of striatal A2ARs using positron emission tomography (PET with [7-methyl-(11C]-(E-8-(3,4,5-trimethoxystyryl-1,3,7-trimethylxanthine ([(11C]TMSX in nine drug-naïve patients with PD, seven PD patients with mild dyskinesia and six elderly control subjects using PET. The patients and eight normal control subjects were also examined for binding ability of dopamine transporters and D2Rs. Seven of the drug-naïve patients underwent a second series of PET scans following therapy. We found that the distribution volume ratio of A2ARs in the putamen were larger in the dyskinesic patients than in the control subjects (p<0.05, Tukey-Kramer post hoc test. In the drug-naïve patients, the binding ability of the A2ARs in the putamen, but not in the head of caudate nucleus, was significantly lower on the more affected side than on the less affected side (p<0.05, paired t-test. In addition, the A2ARs were significantly increased after antiparkinsonian therapy in the bilateral putamen of the drug-naïve patients (p<0.05, paired t-test but not in the bilateral head of caudate nucleus. Our study demonstrated that the A2ARs in the putamen were increased in the PD patients with dyskinesia, and also suggest that the A2ARs in the putamen compensate for the asymmetrical decrease of dopamine in drug-naïve PD patients and that antiparkinsonian therapy increases the A2ARs in the putamen. The A2ARs may play an

  10. Identification of Bloch-modes in hollow-core Photonic Crystal Fiber cladding

    DEFF Research Database (Denmark)

    Couny, F.; Benabid, F.; Roberts, John

    2007-01-01

    length of fiber. A detailed study of the modes near the edges of the band gap shows that it is formed by the influence of three types of resonator: the glass interstitial apex, the silica strut which joins the neighboring apexes, and the air hole. The cladding electromagnetic field which survives......We report on the experimental visualization of the cladding Bloch-modes of a hollow-core photonic crystal fiber. Both spectral and spatial field information is extracted using the approach, which is based on measurement of the near-field and Fresnel-zone that results after propagation over a short...

  11. Maurice Halbwachs e Marc Bloch em torno do conceito de memória coletiva

    Directory of Open Access Journals (Sweden)

    Eliza Bachega Casadei

    2010-05-01

    Full Text Available

    After noting that the concept of “collective memory” has become increasingly important for many areas of Humanities, this paper proposes the study of discussions between the inventor of the term, Maurice Halbwachs and historian Marc Bloch around this theme. Halbwachs was pioneer when he took away the memory of a sphere merely individual and Bloch added the problem of collective memories’ transmission. The purpose of this paper is to rescue this debate and study how it influenced the subsequent developments around the theme.

    A partir da constatação de que o conceito de “memória coletiva” tem se tornado cada vez mais importante para diversas áreas das Ciências Humanas, o presente artigo propõe o estudo da discussão entre o inventor do termo, Maurice Halbwachs e o historiador Marc Bloch em torno desta temática. Ao passo em que Halbwachs estabelece, pioneiramente, um trabalho que retira a memória de uma esfera meramente individual, Bloch acrescenta a problemática da transmissão das lembranças coletivas. O objetivo do presente texto é resgatar esse debate, bem como estudar como ele influenciou nos desdobramentos posteriores em torno do tema.

  12. Self-consistent Maxwell-Bloch model of quantum-dot photonic-crystal-cavity lasers

    DEFF Research Database (Denmark)

    Cartar, William; Mørk, Jesper; Hughes, Stephen

    2017-01-01

    We present a powerful computational approach to simulate the threshold behavior of photonic-crystal quantum-dot (QD) lasers. Using a finite-difference time-domain (FDTD) technique, Maxwell-Bloch equations representing a system of thousands of statistically independent and randomly positioned two...... by matching the cavity quality factors and resonance properties. We also demonstrate how to obtain the correct point-dipole radiative decay rate from Fermi's golden rule, which is captured naturally by the FDTD method. Our numerical simulations predict that the pump threshold plateaus around cavity lengths...

  13. LDRD final report on Bloch Oscillations in two-dimensional nanostructure arrays for high frequency applications.

    Energy Technology Data Exchange (ETDEWEB)

    Lyo, Sungkwun Kenneth; Pan, Wei; Reno, John Louis; Wendt, Joel Robert; Barton, Daniel Lee

    2008-09-01

    We have investigated the physics of Bloch oscillations (BO) of electrons, engineered in high mobility quantum wells patterned into lateral periodic arrays of nanostructures, i.e. two-dimensional (2D) quantum dot superlattices (QDSLs). A BO occurs when an electron moves out of the Brillouin zone (BZ) in response to a DC electric field, passing back into the BZ on the opposite side. This results in quantum oscillations of the electron--i.e., a high frequency AC current in response to a DC voltage. Thus, engineering a BO will yield continuously electrically tunable high-frequency sources (and detectors) for sensor applications, and be a physics tour-de-force. More than a decade ago, Bloch oscillation (BO) was observed in a quantum well superlattice (QWSL) in short-pulse optical experiments. However, its potential as electrically biased high frequency source and detector so far has not been realized. This is partially due to fast damping of BO in QWSLs. In this project, we have investigated the possibility of improving the stability of BO by fabricating lateral superlattices of periodic coupled nanostructures, such as metal grid, quantum (anti)dots arrays, in high quality GaAs/Al{sub x}Ga{sub 1-x}As heterostructures. In these nanostructures, the lateral quantum confinement has been shown theoretically to suppress the optical-phonon scattering, believed to be the main mechanism for fast damping of BO in QWSLs. Over the last three years, we have made great progress toward demonstrating Bloch oscillations in QDSLs. In the first two years of this project, we studied the negative differential conductance and the Bloch radiation induced edge-magnetoplasmon resonance. Recently, in collaboration with Prof. Kono's group at Rice University, we investigated the time-domain THz magneto-spectroscopy measurements in QDSLs and two-dimensional electron systems. A surprising DC electrical field induced THz phase flip was observed. More measurements are planned to investigate this

  14. Optical surface edge Bloch modes: low-loss subwavelength-scale 2D light localization

    CERN Document Server

    Su, Shu-Yu

    2012-01-01

    Edge modes of a finite-size woodpile can appear within a complete bandgap on an edge. The mode area is as small as 0.066 squared half-in-vacuum-wavelengths, and the propagation loss is small. The field maxima occur at a dielectric-vacuum interface, like at a metal-dielectric interface for surface plasmon modes. The edge mode is a subwavelength-scale 2D light localization mode in non-metallic materials. Analysis of two-mode co-directional coupling between identical surface Bloch modes suggests that a large photonic crystal or surface designing would be needed for suppressing the evanescent field coupling in the woodpile.

  15. Motives and algebraic cycles a celebration in honour of Spencer J. Bloch

    CERN Document Server

    Jeu, Rob de; Lewis, James D

    2009-01-01

    Spencer J. Bloch has, and continues to have, a profound influence on the subject of Algebraic K-Theory, Cycles and Motives. This book, which is comprised of a number of independent research articles written by leading experts in the field, is dedicated in his honour, and gives a snapshot of the current and evolving nature of the subject. Some of the articles are written in an expository style, providing a perspective on the current state of the subject to those wishing to learn more about it. Others are more technical, representing new developments and making them especially interesting to res

  16. Proof of an entropy conjecture for Bloch coherent spin states and its generalizations

    DEFF Research Database (Denmark)

    H. Lieb, Elliott; Solovej, Jan Philip

    2014-01-01

    Wehrl used Glauber coherent states to define a map from quantum density matrices to classical phase space densities and conjectured that for Glauber coherent states the mininimum classical entropy would occur for density matrices equal to projectors onto coherent states. This was proved by Lieb...... in 1978 who also extended the conjecture to Bloch SU(2) spin-coherent states for every angular momentum $J$. This conjecture is proved here. We also recall our 1991 extension of the Wehrl map to a quantum channel from $J$ to $K=J+1/2, J+1, ...$, with $K=\\infty$ corresponding to the Wehrl map to classical...

  17. Anastrepha ludens and Anastrepha serpentina (Diptera: Tephritidae) do not infest Psidium guajava (Myrtaceae), but Anastrepha obliqua occasionally shares this resource with Anastrepha striata in nature.

    Science.gov (United States)

    Birke, Andrea; Aluja, Martin

    2011-08-01

    This study examined whether economically important fruit fly species Anastrepha ludens (Loew), Anastrepha serpentina (Wiedemann), and Anastrepha obliqua (Macquart) (Diptera: Tephritidae) may opportunistically exploit guavas, Psidium guajava L. (Myrtaceae), growing near preferred natural hosts. We collected 3,459 kg of guavas and 895 kg of other known host species [sour orange, Citrus aurantium L.; grapefruit, Citrus paradisi Macfadyen; mango, Mangifera indica L.; white sapote, Casimiroa edulis La Llave and Lex.; sapote, Pouteria sapota (Jacq.); sapodilla, Manilkara zapota L.; and wild plum, Spondias purpurea L. and Spondias mombin L.] along an altitudinal gradient over a 4-yr period (2006-2009). Plants were growing in sympatry in 23 localities where the guavas are usually infested in the state of Veracruz, M6xico. The guava samples yielded 20,341 Anastrepha spp. pupae in total (overall mean, 5.88 pupae per kg of fruit). Confirming previous reports, Anastrepha fraterculus (Wiedemann) and Anastrepha striata (Schiner) were found heavily infesting guavas in Veracruz. Importantly, although we did not find evidence that A. ludens and A. serpentina are able to attack this valuable commodity, we document for the first time in the agriculturally important state of Veracruz that P. guajava is an alternative natural host plant of A. obliqua. We recovered two fruit in the mango-growing locality of la Vibora, Tlalixcoyan, that harbored larvae of A. striata and A. obliqua. This finding has important practical implications for management of A. obliqua. Over the entire altitudinal gradient, when individual fruit infestation was examined, a dynamic pattern of species dominance was unveiled with guavas growing below 800 m above sea level mainly attacked by A. striata and a progressive replacement with increasing altitude by A. fraterculus. Interestingly, most individual fruit examined (97%) harbored a single species of fruit fly, a finding that may be taken as evidence of

  18. Wannier-Bloch approach to localization in high harmonics generation in solids

    CERN Document Server

    Osika, Edyta N; Ortmann, Lisa; Suárez, Noslen; Pérez-Hernández, Jose Antonio; Szafran, Bartłomiej; Ciappina, Marcelo F; Sols, Fernando; Landsman, Alexandra S; Lewenstein, Maciej

    2016-01-01

    Emission of high-order harmonics from solids provides a new avenue in attosecond science. On one hand, it allows to investigate fundamental processes of the non-linear response of electrons driven by a strong laser pulse in a periodic crystal lattice. On the other hand, it opens new paths toward efficient attosecond pulse generation, novel imaging of electronic wave functions, and enhancement of high-order harmonic generation (HHG) intensity. A key feature of HHG in a solid (as compared to the well-understood phenomena of HHG in an atomic gas) is the delocalization of the process, whereby an electron ionized from one site in the periodic lattice may recombine with any other. Here, we develop an analytic model, based on the localized Wannier wave functions in the valence band and delocalized Bloch functions in the conduction band. This Wannier-Bloch approach assesses the contributions of individual lattice sites to the HHG process, and hence addresses precisely the question of localization of harmonic emission...

  19. Rabi-Bloch oscillations in spatially distributed systems: Temporal dynamics and frequency spectra

    Science.gov (United States)

    Levie, Ilay; Kastner, Raphael; Slepyan, Gregory

    2017-10-01

    We consider one-dimensional chains of two-level quantum systems coupled via tunneling. The chain is driven by the superposition of dc and ac fields in the strong coupling regime. Based on the fundamental principles of electrodynamics and quantum theory, we have developed a generalized model of quantum dynamics for such interactions, free of rotating-wave approximation. The system of equations of motion was studied numerically. We analyzed the dynamics and spectra of the inversion density, dipole current density, and tunneling current density. In the case of resonant interaction with the ac component, the particle dynamics exhibits itself in the oscillatory regime, which may be interpreted as a combination of Rabi and Bloch oscillations with their strong mutual influence. Such scenario for an obliquely incident ac field dramatically differs from the individual picture of both types of oscillations due to the interactions. This effect is counterintuitive because of the existence of markedly different frequency ranges for such two types of oscillations. These dynamics manifest themselves in multiline spectra in different combinations of Rabi and Bloch frequencies. The effect is promising as a framework of a new type of spectroscopy in nanoelectronics and electrical control of nanodevices.

  20. Solving the Bloch equation with periodic excitation using harmonic balancing: application to Rabi modulated excitation.

    Science.gov (United States)

    Tahayori, Bahman; Johnston, Leigh A; Layton, Kelvin J; Farrell, Peter M; Mareels, Iven M Y

    2015-10-01

    In waveform design for magnetic resonance applications, periodic continuous-wave excitation offers potential advantages that remain largely unexplored because of a lack of understanding of the Bloch equation with periodic continuous-wave excitations. Using harmonic balancing techniques the steady state solutions of the Bloch equation with periodic excitation can be effectively solved. Moreover, the convergence speed of the proposed series approximation is such that a few terms in the series expansion suffice to obtain a very accurate description of the steady state solution. The accuracy of the proposed analytic approximate series solution is verified using both a simulation study as well as experimental data derived from a spherical phantom with doped water under continuous-wave excitation. Typically a five term series suffices to achieve a relative error of less than one percent, allowing for a very effective and efficient analytical design process. The opportunities for Rabi frequency modulated continuous-wave form excitation are then explored, based on a comparison with steady state free precession pulse sequences.

  1. Transport of Photonic Bloch Wave in Arrayed Two-Level Atoms.

    Science.gov (United States)

    Chang, Chih-Chun; Lin, Lee; Chen, Guang-Yin

    2018-01-24

    In a quantum system of arrayed two-level atoms interacting with light, the interacted (dressed) photon is propagating in a periodic medium and its eigenstate ought to be of Bloch type with lattice symmetry. As the energy of photon is around the spacing between the two atomic energy levels, the photon will be absorbed and is not in the propagating mode but the attenuated mode. Therefore an energy gap exists in the dispersion relation of the photonic Bloch wave of dressed photon in addition to the nonlinear behaviors due to atom-light interactions. There follows several interesting results which are distinct from those obtained through a linear dispersion relation of free photon. For example, slow light can exist, the density of state of dressed photon is non-Lorentzian and is very large around the energy gap; the Rabi oscillations become monotonically decreasing in some cases; and besides the superradiance occurs at long wavelengths, the spontaneous emission is also very strong near the energy gap because of the high density of state.

  2. Bloch Waves in Minimal Landau Gauge and the Infinite-Volume Limit of Lattice Gauge Theory.

    Science.gov (United States)

    Cucchieri, Attilio; Mendes, Tereza

    2017-05-12

    By exploiting the similarity between Bloch's theorem for electrons in crystalline solids and the problem of Landau gauge fixing in Yang-Mills theory on a "replicated" lattice, we show that large-volume results can be reproduced by simulations performed on much smaller lattices. This approach, proposed by Zwanziger [Nucl. Phys. B412, 657 (1994)NUPBBO0550-321310.1016/0550-3213(94)90396-4], corresponds to taking the infinite-volume limit for Landau-gauge field configurations in two steps: first for the gauge transformation alone, while keeping the lattice volume finite, and second for the gauge-field configuration itself. The solutions to the gauge-fixing condition are then given in terms of Bloch waves. Applying the method to data from Monte Carlo simulations of pure SU(2) gauge theory in two and three space-time dimensions, we are able to evaluate the Landau-gauge gluon propagator for lattices of linear extent up to 16 times larger than that of the simulated lattice. This approach is reminiscent of the Fisher-Ruelle construction of the thermodynamic limit in classical statistical mechanics.

  3. Anomalous diffusion expressed through fractional order differential operators in the Bloch-Torrey equation.

    Science.gov (United States)

    Magin, Richard L; Abdullah, Osama; Baleanu, Dumitru; Zhou, Xiaohong Joe

    2008-02-01

    Diffusion weighted MRI is used clinically to detect and characterize neurodegenerative, malignant and ischemic diseases. The correlation between developing pathology and localized diffusion relies on diffusion-weighted pulse sequences to probe biophysical models of molecular diffusion-typically exp[-(bD)]-where D is the apparent diffusion coefficient (mm(2)/s) and b depends on the specific gradient pulse sequence parameters. Several recent studies have investigated the so-called anomalous diffusion stretched exponential model-exp[-(bD)(alpha)], where alpha is a measure of tissue complexity that can be derived from fractal models of tissue structure. In this paper we propose an alternative derivation for the stretched exponential model using fractional order space and time derivatives. First, we consider the case where the spatial Laplacian in the Bloch-Torrey equation is generalized to incorporate a fractional order Brownian model of diffusivity. Second, we consider the case where the time derivative in the Bloch-Torrey equation is replaced by a Riemann-Liouville fractional order time derivative expressed in the Caputo form. Both cases revert to the classical results for integer order operations. Fractional order dynamics derived for the first case were observed to fit the signal attenuation in diffusion-weighted images obtained from Sephadex gels, human articular cartilage and human brain. Future developments of this approach may be useful for classifying anomalous diffusion in tissues with developing pathology.

  4. Bloch Waves in Minimal Landau Gauge and the Infinite-Volume Limit of Lattice Gauge Theory

    Science.gov (United States)

    Cucchieri, Attilio; Mendes, Tereza

    2017-05-01

    By exploiting the similarity between Bloch's theorem for electrons in crystalline solids and the problem of Landau gauge fixing in Yang-Mills theory on a "replicated" lattice, we show that large-volume results can be reproduced by simulations performed on much smaller lattices. This approach, proposed by Zwanziger [Nucl. Phys. B412, 657 (1994), 10.1016/0550-3213(94)90396-4], corresponds to taking the infinite-volume limit for Landau-gauge field configurations in two steps: first for the gauge transformation alone, while keeping the lattice volume finite, and second for the gauge-field configuration itself. The solutions to the gauge-fixing condition are then given in terms of Bloch waves. Applying the method to data from Monte Carlo simulations of pure SU(2) gauge theory in two and three space-time dimensions, we are able to evaluate the Landau-gauge gluon propagator for lattices of linear extent up to 16 times larger than that of the simulated lattice. This approach is reminiscent of the Fisher-Ruelle construction of the thermodynamic limit in classical statistical mechanics.

  5. Nonlinear Bloch waves and current states of exciton-polariton condensates

    Science.gov (United States)

    Chestnov, I. Yu.; Yulin, A. V.; Alodjants, A. P.; Egorov, O. A.

    2016-09-01

    The formation of nonlinear Bloch states in open driven-dissipative systems of exciton-polaritons loaded into a weak-contrast 1D periodic lattice is studied numerically and analytically. The condensate is described within the framework of mean-field theory by the coupled equations for the order parameter and for the density of incoherent excitons. The stationary nonlinear solutions having the structure of Bloch waves are studied in detail. It is shown that there is a bifurcation leading to the appearance of a family of essentially nonlinear states. The special feature of these solutions is that its current does not vanish when the quasimomentum of the state approaches the values equal to half of the lattice constant. To explain the bifurcations found in numerical simulations a simple perturbative approach is developed. The stability of the nonlinear states is examined by linear spectral analysis and by direct numerical simulations. An experimental scheme allowing the observation of the discussed nonlinear current states is suggested and studied by numerical simulations.

  6. Wannier-Bloch Approach to Localization in High-Harmonics Generation in Solids

    Directory of Open Access Journals (Sweden)

    Edyta N. Osika

    2017-05-01

    Full Text Available Emission of high-order harmonics from solids provides a new avenue in attosecond science. On the one hand, it allows us to investigate fundamental processes of the nonlinear response of electrons driven by a strong laser pulse in a periodic crystal lattice. On the other hand, it opens new paths toward efficient attosecond pulse generation, novel imaging of electronic wave functions, and enhancement of high-order harmonic-generation (HHG intensity. A key feature of HHG in a solid (as compared to the well-understood phenomenon of HHG in an atomic gas is the delocalization of the process, whereby an electron ionized from one site in the periodic lattice may recombine in any other. Here, we develop an analytic model, based on the localized Wannier wave functions in the valence band and delocalized Bloch functions in the conduction band. This Wannier-Bloch approach assesses the contributions of individual lattice sites to the HHG process and hence precisely addresses the question of localization of harmonic emission in solids. We apply this model to investigate HHG in a ZnO crystal for two different orientations, corresponding to wider and narrower valence and conduction bands, respectively. Interestingly, for narrower bands, the HHG process shows significant localization, similar to harmonic generation in atoms. For all cases, the delocalized contributions to HHG emission are highest near the band-gap energy. Our results pave the way to controlling localized contributions to HHG in a solid crystal.

  7. Quantitative evaluation of protocorm growth and fungal colonization in Bletilla striata (Orchidaceae) reveals less-productive symbiosis with a non-native symbiotic fungus.

    Science.gov (United States)

    Yamamoto, Tatsuki; Miura, Chihiro; Fuji, Masako; Nagata, Shotaro; Otani, Yuria; Yagame, Takahiro; Yamato, Masahide; Kaminaka, Hironori

    2017-02-21

    In nature, orchid plants depend completely on symbiotic fungi for their nutrition at the germination and the subsequent seedling (protocorm) stages. However, only limited quantitative methods for evaluating the orchid-fungus interactions at the protocorm stage are currently available, which greatly constrains our understanding of the symbiosis. Here, we aimed to improve and integrate quantitative evaluations of the growth and fungal colonization in the protocorms of a terrestrial orchid, Blettila striata, growing on a plate medium. We achieved both symbiotic and asymbiotic germinations for the terrestrial orchid B. striata. The protocorms produced by the two germination methods grew almost synchronously for the first three weeks. At week four, however, the length was significantly lower in the symbiotic protocorms. Interestingly, the dry weight of symbiotic protocorms did not significantly change during the growth period, which implies that there was only limited transfer of carbon compounds from the fungus to the protocorms in this relationship. Next, to evaluate the orchid-fungus interactions, we developed an ink-staining method to observe the hyphal coils in protocorms without preparing thin sections. Crushing the protocorm under the coverglass enables us to observe all hyphal coils in the protocorms with high resolution. For this observation, we established a criterion to categorize the stages of hyphal coils, depending on development and degradation. By counting the symbiotic cells within each stage, it was possible to quantitatively evaluate the orchid-fungus symbiosis. We describe a method for quantitative evaluation of orchid-fungus symbiosis by integrating the measurements of plant growth and fungal colonization. The current study revealed that although fungal colonization was observed in the symbiotic protocorms, the weight of the protocorm did not significantly increase, which is probably due to the incompatibility of the fungus in this symbiosis. These

  8. Ising and Bloch domain walls in a two-dimensional parametrically driven Ginzburg-Landau equation model with nonlinearity management

    DEFF Research Database (Denmark)

    Gaididei, Yu. B.; Christiansen, Peter Leth

    2008-01-01

    We study a parametrically driven Ginzburg-Landau equation model with nonlinear management. The system is made of laterally coupled long active waveguides placed along a circumference. Stationary solutions of three kinds are found: periodic Ising states and two types of Bloch states, staggered and...

  9. A 2D multi-term time and space fractional Bloch-Torrey model based on bilinear rectangular finite elements

    Science.gov (United States)

    Qin, Shanlin; Liu, Fawang; Turner, Ian W.

    2018-03-01

    The consideration of diffusion processes in magnetic resonance imaging (MRI) signal attenuation is classically described by the Bloch-Torrey equation. However, many recent works highlight the distinct deviation in MRI signal decay due to anomalous diffusion, which motivates the fractional order generalization of the Bloch-Torrey equation. In this work, we study the two-dimensional multi-term time and space fractional diffusion equation generalized from the time and space fractional Bloch-Torrey equation. By using the Galerkin finite element method with a structured mesh consisting of rectangular elements to discretize in space and the L1 approximation of the Caputo fractional derivative in time, a fully discrete numerical scheme is derived. A rigorous analysis of stability and error estimation is provided. Numerical experiments in the square and L-shaped domains are performed to give an insight into the efficiency and reliability of our method. Then the scheme is applied to solve the multi-term time and space fractional Bloch-Torrey equation, which shows that the extra time derivative terms impact the relaxation process.

  10. Permittivity and Permeability for Floquet-Bloch Space Harmonics in Infinite 1D Magneto-Dielectric Periodic Structures

    DEFF Research Database (Denmark)

    Breinbjerg, Olav; Yaghjian, Arthur D.

    2014-01-01

    -Bloch space harmonics. We discuss how space harmonic permittivity and permeability can be expressed in seemingly different though equivalent forms, and we investigate these parameters of the zeroeth order space harmonic for a particular 1D periodic structure that is based on a previously reported 3D periodic...

  11. Notes on the genus Amphiprion Bloch & Schneider, 1801 (Teleostei: Pomacentridae) and its host sea anemones in the Seychelles

    NARCIS (Netherlands)

    Hartog, den J.C.

    1997-01-01

    The genus Amphiprion Bloch & Schneider, 1801, is represented in the Seychelles by two species, A. akallopisos Bleeker, 1853, and the endemic A. fuscocaudatus Allen, 1972. Throughout its distributional range Amphiprion akallopisos has exclusively been recorded to associate with the clownfish anemones

  12. Boundedness and compactness of a new product-type operator from a general space to Bloch-type spaces

    Directory of Open Access Journals (Sweden)

    Stevo Stević

    2016-09-01

    Full Text Available Abstract We characterize the boundedness and compactness of a product-type operator, which, among others, includes all the products of the single composition, multiplication, and differentiation operators, from a general space to Bloch-type spaces. We also give some upper and lower bounds for the norm of the operator.

  13. The Bloch wave operator: generalizations and applications: Part I. The time-independent case

    Energy Technology Data Exchange (ETDEWEB)

    Killingbeck, John P [Mathematics Department, University of Hull, Hull HU6 7RX (United Kingdom); Jolicard, Georges [Observatoire de Besancon (UMR-CNRS 6091), Universite de Franche-Comte, 41 bis, Avenue de l' Observatoire, 25000 Besancon (France)

    2003-05-23

    This is part 1 of a two-part review on wave operator theory and methods. The basic theory of the time-independent wave operator is presented in terms of partitioned matrix theory for the benefit of general readers, with a discussion of the links between the matrix and projection operator approaches. The matrix approach is shown to lead to simple derivations of the wave operators and effective Hamiltonians of Loewdin, Bloch, Des Cloizeaux and Kato as well as to some associated variational forms. The principal approach used throughout stresses the solution of the nonlinear equation for the reduced wave operator, leading to the construction of the effective Hamiltonians of Bloch and of Des Cloizeaux. Several mathematical techniques which are useful in implementing this approach are explained, some of them being relatively little known in the area of wave operator calculations. The theoretical discussion is accompanied by several specimen numerical calculations which apply the described techniques to a selection of test matrices taken from the previous literature on wave operator methods. The main emphasis throughout is on the use of numerical methods which use iterative or perturbation algorithms, with simple Pade approximant methods being found sufficient to deal with most of the cases of divergence which are encountered. The use of damping factors and relaxation parameters is found to be effective in stabilizing calculations which use the energy-dependent effective Hamiltonian of Loewdin. In general the computations suggest that the numerical applications of the nonlinear equation for the reduced wave operator are best carried out with the equation split into a pair of equations in which the Bloch effective Hamiltonian appears as a separate entity. The presentation of the theoretical and computational details throughout is accompanied by references to and discussion of many works which have used wave operator methods in physics, chemistry and engineering. Some of

  14. Self-consistent Maxwell-Bloch model of quantum-dot photonic-crystal-cavity lasers

    Science.gov (United States)

    Cartar, William; Mørk, Jesper; Hughes, Stephen

    2017-08-01

    We present a powerful computational approach to simulate the threshold behavior of photonic-crystal quantum-dot (QD) lasers. Using a finite-difference time-domain (FDTD) technique, Maxwell-Bloch equations representing a system of thousands of statistically independent and randomly positioned two-level emitters are solved numerically. Phenomenological pure dephasing and incoherent pumping is added to the optical Bloch equations to allow for a dynamical lasing regime, but the cavity-mediated radiative dynamics and gain coupling of each QD dipole (artificial atom) is contained self-consistently within the model. These Maxwell-Bloch equations are implemented by using Lumerical's flexible material plug-in tool, which allows a user to define additional equations of motion for the nonlinear polarization. We implement the gain ensemble within triangular-lattice photonic-crystal cavities of various length N (where N refers to the number of missing holes), and investigate the cavity mode characteristics and the threshold regime as a function of cavity length. We develop effective two-dimensional model simulations which are derived after studying the full three-dimensional passive material structures by matching the cavity quality factors and resonance properties. We also demonstrate how to obtain the correct point-dipole radiative decay rate from Fermi's golden rule, which is captured naturally by the FDTD method. Our numerical simulations predict that the pump threshold plateaus around cavity lengths greater than N =9 , which we identify as a consequence of the complex spatial dynamics and gain coupling from the inhomogeneous QD ensemble. This behavior is not expected from simple rate-equation analysis commonly adopted in the literature, but is in qualitative agreement with recent experiments. Single-mode to multimode lasing is also observed, depending on the spectral peak frequency of the QD ensemble. Using a statistical modal analysis of the average decay rates, we also

  15. Novel Tetra-nucleotide Microsatellite DNA Markers for Assessing the Evolutionary Genetics and Demographics of Northern Snakehead (Channa argus) Invading North America

    Science.gov (United States)

    King, Timothy L.; Johnson, R.L.

    2011-01-01

    We document the isolation and characterization of 19 tetra-nucleotide microsatellite DNA markers in northern snakehead (Channa argus) fish that recently colonized Meadow Lake, New York City, New York. These markers displayed moderate levels of allelic diversity (averaging 6.8 alleles/locus) and heterozygosity (averaging 74.2%). Demographic analyses suggested that the Meadow Lake collection has not achieved mutation-drift equilibrium. These results were consistent with instances of deviations from Hardy-Weinberg equilibrium and the presence of some linkage disequilibrium. A comparison of individual pair-wise distances suggested the presence of multiple differentiated groups of related individuals. Results of all analyses are consistent with a pattern of multiple, recent introductions. The microsatellite markers developed for C. argus yielded sufficient genetic diversity to potentially: (1) delineate kinship; (2) elucidate fine-scale population structure; (3) define management (eradication) units; (4) estimate dispersal rates; (5) estimate population sizes; and (6) provide unique demographic perspectives of control or eradication effectiveness

  16. Cross talk between arsenic and cold on the regulation of inorganic phosphate level in peripheral tissues of fresh water fishes (Channa punctata

    Directory of Open Access Journals (Sweden)

    Md. Shahidul Haque

    2013-01-01

    Full Text Available Cold acclimation shows the increased Pi in skeletal muscle of Channa punctata variety of fishes after 1 h and 2 h while reduces at prolonged exposure (4 h. Similar stimulatory effects were observed in heart, however, reduced at 30 min and 4 h and in liver it causes prevention of Pi release after 30 min, 1 h, 2 h and 4 h respectively. In gastrointestinal tract, the effects were pronounced whenever the fishes were exposed to cold for 1 h and 2 h, while reduced activity was demonstrated after 4 h of the treatment. To clarify the role of arsenic on cold-induced Pi release, fishes were exposed to Na2HAsO4 which reduced the effect in skeletal muscle, gastrointestinal tract and heart effectively and significantly. Whenever the fishes were exposed to cold with arsenic, the amount of Pi was also reduced than the control. In liver of arsenic treated fishes, the increased results were found while in cold, the values were reduced again in presence of arsenic compared to control and cold exposed fishes. Our findings give a new insight for the regulation of adaptive response tissue specifically and differentially and arsenic might be involved in cross talk through impairment of the cold-induced effect.

  17. A utopia concreta e o ainda-não-consciente na obra de Ernst Bloch

    OpenAIRE

    Viana, Francisco Antonio Marques

    2015-01-01

    O pensamento de Ernst Bloch é complexo, sua obra é extensa e, em geral, tem sido analisado pelas suas feições messiânicas, utópicas, místicas ou ainda pela sua possível repercussão na América Latina e pelo ângulo da esperança. Esta tese, investiga a filosofia blochiana como fonte de renovação e extensão do marxismo, em dois momentos interligados a uma mesma ideia: a revolução socialista, iluminada pela libertação do homem do modo de produção capitalista e a construção da vida melhor. O primei...

  18. Sub- and superluminal kink-like waves in the kinetic limit of Maxwell-Bloch equations

    Energy Technology Data Exchange (ETDEWEB)

    Janowicz, Maciej [Instytut Fizyki Polskiej Akademii Nauk, Aleja Lotnikow 32/46, 02-668 Warszawa (Poland); Holthaus, Martin, E-mail: mjanow@ifpan.edu.pl [Institut fuer Physik, Carl von Ossietzky Universitaet, D-26111 Oldenburg (Germany)

    2011-01-14

    Running-wave solutions to three systems of partial differential equations describing wave propagation in atomic media in the kinetic limit have been obtained. Those systems include approximations to (i) standard two-level Maxwell-Bloch equations; (ii) equations describing processes with saturated absorption in three-level systems and (iii) equations describing processes with reversed saturation in four-level systems. It has been shown that in all three cases kink-like solitary waves can emerge if the dynamical equation for the intensity includes a linear contribution to the Lambert-Beer law. Those solitary waves can propagate with either sub- or superluminal velocity of the edge of the kink, and in a direction which can be either the same as or opposite to that of the carrier wave. In addition, simple qualitative information about the behaviour of waves near the wavefronts has been obtained.

  19. Experimental demonstration of critical coupling of whispering gallery mode cavities on a Bloch surface wave platform.

    Science.gov (United States)

    Vosoughi Lahijani, B; Badri Ghavifekr, H; Dubey, R; Kim, M-S; Vartiainen, I; Roussey, M; Herzig, H P

    2017-12-15

    We experimentally demonstrate critical coupling of whispering gallery mode (WGM) disk resonators implemented on a Bloch surface wave platform using scanning near-field optical microscopy. The studied structure is a 60 nm thick TiO2 WGM disk cavity (radius of 100 μm) operating within the C-band telecommunication wavelength. An extinction ratio of 26 dB and a quality factor of 2200 are measured. Such a high extinction ratio verifies the critical coupling of the WGM resonator. This result paves the way to planar optical signal processing devices based on the proposed geometry, for which a critical coupling condition is a guarantee of optimum performance.

  20. Dynamics of Peregrine combs and Peregrine walls in an inhomogeneous Hirota and Maxwell-Bloch system

    Science.gov (United States)

    Wang, Lei; Wang, Zi-Qi; Sun, Wen-Rong; Shi, Yu-Ying; Li, Min; Xu, Min

    2017-06-01

    Under investigation in this paper is an inhomogeneous Hirota-Maxwell-Bloch (IHMB) system which can describe the propagation of optical solitons in an erbium-doped optical fiber. The breather multiple births (BMBs) are derived with periodically varying group velocity dispersion (GVD) coefficients. Under large periodic modulations in the GVD coefficient of IHMB system, the Peregrine comb (PC) solution is produced, which can be viewed as the limiting case of the BMBs. When the amplitude of the modulation satisfies a special condition, the Peregrine wall (PW) that can be regarded as an intermediate state between rogue wave and PC is obtained. The effects of the third-order dispersion on the spatiotemporal characteristics of PCs and PWs are studied. Our results may be useful for the experimental control and manipulation of the formation of generalized Peregrine rogue waves in inhomogeneous erbium-doped optical fiber.

  1. Bloch surface waves confined in one dimension with a single polymeric nanofibre

    Science.gov (United States)

    Wang, Ruxue; Xia, Hongyan; Zhang, Douguo; Chen, Junxue; Zhu, Liangfu; Wang, Yong; Yang, Erchan; Zang, Tianyang; Wen, Xiaolei; Zou, Gang; Wang, Pei; Ming, Hai; Badugu, Ramachandram; Lakowicz, Joseph R.

    2017-02-01

    Polymeric fibres with small radii (such as ≤125 nm) are delicate to handle and should be laid down on a solid substrate to obtain practical devices. However, placing these nanofibres on commonly used glass substrates prevents them from guiding light. In this study, we numerically and experimentally demonstrate that when the nanofibre is placed on a suitable dielectric multilayer, it supports a guided mode, a Bloch surface wave (BSW) confined in one dimension. The physical origin of this new mode is discussed in comparison with the typical two-dimensional BSW mode. Polymeric nanofibres are easily fabricated to contain fluorophores, which make the dielectric nanofibre and multilayer configuration suitable for developing a large range of new nanometric scale devices, such as processor-memory interconnections, devices with sensitivity to target analytes, incident polarization and multi-colour BSW modes.

  2. Optical Bloch oscillation and Zener tunneling in the fractional Schrödinger equation.

    Science.gov (United States)

    Zhang, Yiqi; Wang, Rong; Zhong, Hua; Zhang, Jingwen; Belić, Milivoj R; Zhang, Yanpeng

    2017-12-19

    We demonstrate optical Bloch oscillation (OBO) and optical Zener tunneling (OZT) in the fractional Schrödinger equation (FSE) with periodic and linear potentials, numerically and theoretically. We investigate in parallel the regular Schrödinger equation and the FSE, by adjusting the Lévy index, and expound the differences between the two. We find that the spreading of the OBO decreases in the fractional case, due to the diminishing band width. Increasing the transverse force, due to the linear potential, leads to the appearance of OZT, but this process is suppressed in the FSE. Our results indicate that the adjustment of the Lévy index can effectively control the emergence of OBO and OZT, which can inspire new ideas in the design of optical switches and interconnects.

  3. Galerkin finite element method for two-dimensional space and time fractional Bloch-Torrey equation

    Science.gov (United States)

    Zhao, Yue; Bu, Weiping; Zhao, Xuan; Tang, Yifa

    2017-12-01

    In this paper, we consider the Galerkin finite element method for the two-dimensional space and time fractional Bloch-Torrey equation (2D-STFBTE). Utilizing the L 2 -1σ formula to discretize temporal Caputo derivative, we obtain the local truncation error with O (τ 3 - α) in the temporal direction, where α is the order of time fractional derivative. Furthermore, the semi-discrete form for the problem is given and, the stability and convergence of the semi-discrete variational formulation are rigorously proved in L2 norm and fractional norm respectively. Then, we derive a fully discrete scheme for the 2D-STFBTE and investigate its convergence theoretically. Finally, extensive numerical results based on linear piecewise polynomials verify the theoretical results and show the effectiveness of the proposed scheme.

  4. The Harmonic Bloch and Besov Spaces on the Real Unit Ball by an Oscillation

    Directory of Open Access Journals (Sweden)

    Xi Fu

    2016-01-01

    Full Text Available Let B be the real unit ball in Rn and f∈CN(B. Given a multi-index m=(m1,…,mn of nonnegative integers with |m|=N, we set the quantity supx∈B,y∈E(x,r,x≠y(1-|x|2α(1-|y|2β|∂mf(x-∂mf(y|/|x-y|γ[x,y]1-γ,  x≠y, where 0≤γ≤1 and α+β=N+1. In terms of it, we characterize harmonic Bloch and Besov spaces on the real unit ball. This generalizes the main results of Yoneda, 2002, into real harmonic setting.

  5. A Bloch modal approach for engineering waveguide and cavity modes in two-dimensional photonic crystals

    DEFF Research Database (Denmark)

    de Lasson, Jakob Rosenkrantz; Kristensen, Philip Trøst; Mørk, Jesper

    2014-01-01

    -normal modes. As opposed to spatial discretization methods like the nite-dierence time-domain method and the nite element method, the present approach satises automatically the outgoing wave boundary condition in the propagation direction which represents a signicant advantage of our new method. The scheme......In open nanophotonic structures, the natural modes are so-called quasi-normal modes satisfying an outgoing wave boundary condition. We present a new scheme based on a modal expansion technique, a scattering matrix approach and Bloch modes of periodic structures for determining these quasi...... uses no external excitation and determines the quasi-normal modes as unity eigenvalues of the cavity roundtrip matrix. We demonstrate the method and the quasi-normal modes for two types of two-dimensional photonic crystal structures, and discuss the quasi-normal mode eld distributions and Q...

  6. Sub-cycle control of terahertz high-harmonic generation by dynamical Bloch oscillations

    CERN Document Server

    Schubert, O; Langer, F; Urbanek, B; Lange, C; Huttner, U; Golde, D; Meier, T; Kira, M; Koch, S W; Huber, R

    2016-01-01

    Ultrafast charge transport in strongly biased semiconductors is at the heart of highspeed electronics, electro-optics, and fundamental solid-state physics. Intense light pulses in the terahertz (THz) spectral range have opened fascinating vistas: Since THz photon energies are far below typical electronic interband resonances, a stable electromagnetic waveform may serve as a precisely adjustable bias. Novel quantum phenomena have been anticipated for THz amplitudes reaching atomic field strengths. We exploit controlled THz waveforms with peak fields of 72 MV/cm to drive coherent interband polarization combined with dynamical Bloch oscillations in semiconducting gallium selenide. These dynamics entail the emission of phase-stable high-harmonic transients, covering the entire THz-to-visible spectral domain between 0.1 and 675 THz. Quantum interference of different ionization paths of accelerated charge carriers is controlled via the waveform of the driving field and explained by a quantum theory of inter- and in...

  7. A Bloch-Torrey Equation for Diffusion in a Deforming Media

    Energy Technology Data Exchange (ETDEWEB)

    Rohmer, Damien; Gullberg, Grant T.

    2006-12-29

    Diffusion Tensor Magnetic Resonance Imaging (DTMRI)technique enables the measurement of diffusion parameters and therefore,informs on the structure of the biological tissue. This technique isapplied with success to the static organs such as brain. However, thediffusion measurement on the dynamically deformable organs such as thein-vivo heart is a complex problem that has however a great potential inthe measurement of cardiac health. In order to understand the behavior ofthe Magnetic Resonance (MR)signal in a deforming media, the Bloch-Torreyequation that leads the MR behavior is expressed in general curvilinearcoordinates. These coordinates enable to follow the heart geometry anddeformations through time. The equation is finally discretized andpresented in a numerical formulation using implicit methods, in order toget a stable scheme that can be applied to any smooth deformations.Diffusion process enables the link between the macroscopic behavior ofmolecules and themicroscopic structure in which they evolve. Themeasurement of diffusion in biological tissues is therefore of majorimportance in understanding the complex underlying structure that cannotbe studied directly. The Diffusion Tensor Magnetic ResonanceImaging(DTMRI) technique enables the measurement of diffusion parametersand therefore provides information on the structure of the biologicaltissue. This technique has been applied with success to static organssuch as the brain. However, diffusion measurement of dynamicallydeformable organs such as the in-vivo heart remains a complex problem,which holds great potential in determining cardiac health. In order tounderstand the behavior of the magnetic resonance (MR) signal in adeforming media, the Bloch-Torrey equation that defines the MR behavioris expressed in general curvilinear coordinates. These coordinates enableus to follow the heart geometry and deformations through time. Theequation is finally discretized and presented in a numerical formulationusing

  8. Anachronism in the writing of History: ¿Error or Possibility? Some reflections about the concept of time in Carlo Ginzburg, Marc Bloch and Georges Didi-Huberman

    National Research Council Canada - National Science Library

    Maria Eugenia Chaves Maldonado

    2016-01-01

    In his unfinished and posthumously published book Apologie pour l’histoire, Marc Bloch bestowed on future historians a seminal legacy of critical reflections on the concept of time as the object of historical analysis...

  9. An Optomechanical Elevator: Transport of a Bloch Oscillating Bose–Einstein Condensate up and down an Optical Lattice by Cavity Sideband Amplification and Cooling

    Directory of Open Access Journals (Sweden)

    B. Prasanna Venkatesh

    2015-12-01

    Full Text Available In this paper we give a new description, in terms of optomechanics, of previous work on the problem of an atomic Bose–Einstein condensate interacting with the optical lattice inside a laser-pumped optical cavity and subject to a bias force, such as gravity. An atomic wave packet in a tilted lattice undergoes Bloch oscillations; in a high-finesse optical cavity the backaction of the atoms on the light leads to a time-dependent modulation of the intracavity lattice depth at the Bloch frequency which can in turn transport the atoms up or down the lattice. In the optomechanical picture, the transport dynamics can be interpreted as a manifestation of dynamical backaction-induced sideband damping/amplification of the Bloch oscillator. Depending on the sign of the pump-cavity detuning, atoms are transported either with or against the bias force accompanied by an up- or down-conversion of the frequency of the pump laser light. We also evaluate the prospects for using the optomechanical Bloch oscillator to make continuous measurements of forces by reading out the Bloch frequency. In this context, we establish the significant result that the optical spring effect is absent and the Bloch frequency is not modified by the backaction.

  10. Simulação de sinais de RMN através das equações de Bloch

    Directory of Open Access Journals (Sweden)

    Tiago Bueno Moraes

    2014-01-01

    Full Text Available The aim of this paper was to present a simple and fast way of simulating Nuclear Magnetic Resonance signals using the Bloch equations. These phenomenological equations describe the classical behavior of macroscopic magnetization and are easily simulated using rotation matrices. Many NMR pulse sequences can be simulated with this formalism, allowing a quantitative description of the influence of many experimental parameters. Finally, the paper presents simulations of conventional sequences such as Single Pulse, Inversion Recovery, Spin Echo and CPMG.

  11. Comment on ``Enhanced transmission of light through a gold film due to excitation of standing surface-plasmon Bloch waves"

    OpenAIRE

    Weiner, J.

    2007-01-01

    The purpose of this comment is first to correct a misapprehension of the role played by composite wave diffraction on surface-wave generation at subwavelength structures and second to point out that periodic Bloch structures are unnecessary for the efficient production of the surface plasmon polariton (SPP) guided mode either as traveling or standing waves. Guided surface waves originate from simple slit or groove edges illuminated under normal incidence, and one-dimensional (1-D) surface cav...

  12. The Bloch wave operator: generalizations and applications: II. The time-dependent case

    Energy Technology Data Exchange (ETDEWEB)

    Jolicard, Georges [Observatoire de Besancon (UMR-CNRS 6091), Universite de Franche-Comte, 41 bis, Avenue de l' Observatoire, 25000 Besancon (France); Killingbeck, John P [Observatoire de Besancon (UMR-CNRS 6091), Universite de Franche-Comte, 41 bis, Avenue de l' Observatoire, 25000 Besancon (France); Mathematics Department, University of Hull, Hull HU6 7RX (United Kingdom)

    2003-10-10

    Part II of the review shows how the stationary Bloch wave operator of part I can be suitably modified to give a time-dependent wave operator. This operator makes it possible to use a relatively small active space in order to describe the dynamical processes which occur in quantum mechanical systems which have a time-dependent Hamiltonian. A close study is made of the links between the time-dependent and time-independent wave operators at the adiabatic limit; the analysis clarifies the way in which the wave operator formalism allows the time evolution of a system or a wave packet to be described in terms of a fast evolution inside the active space together with weak transitions out of this space which can be treated by perturbation methods. Two alternative wave operator equations of motion are derived and analysed. The first one is a non-linear differential equation in the usual Hilbert space; the second one is a differential equation in an extended Hilbert space with an extra time variable added and becomes equivalent to the usual Bloch equation when the Floquet Hamiltonian is taken in place of the ordinary Hamiltonian. A study is made of the close relationships between the time-dependent wave operator formalism, the Floquet theory and the (t, t') theory. Some original methods of solution of the two forms of wave operator equation are proposed and lead to new techniques of integration for the time-dependent Schroedinger equation (e.g., the generalized Green equation procedure). Mixed procedures involving both the time-independent and time-dependent wave operators are shown to be applicable to the internal eigenstate problem for large complex matrices. A detailed account is given of the description of inelastic and photoreactive processes by means of the time-dependent wave operator formalism, with particular attention to laser-molecule interactions. The emphasis is on projection operator techniques, with special attention being given to the method of selection

  13. Quantum transport and the Wigner distribution function for Bloch electrons in spatially homogeneous electric and magnetic fields

    Science.gov (United States)

    Iafrate, G. J.; Sokolov, V. N.; Krieger, J. B.

    2017-10-01

    The theory of Bloch electron dynamics for carriers in homogeneous electric and magnetic fields of arbitrary time dependence is developed in the framework of the Liouville equation. The Wigner distribution function (WDF) is determined from the single-particle density matrix in the ballistic regime, i.e., collision effects are excluded. In the theory, the single-particle transport equation is established with the electric field described in the vector potential gauge, and the magnetic field is treated in the symmetric gauge. No specific assumptions are made concerning the form of the initial distribution in momentum or configuration space. The general approach is to employ the accelerated Bloch state representation (ABR) as a basis so that the dependence upon the electric field, including multiband Zener tunneling, is treated exactly. Further, in the formulation of the WDF, we transform to a new set of variables so that the final WDF is gauge invariant and is expressed explicitly in terms of the position, kinetic momentum, and time. The methodology for developing the WDF is illustrated by deriving the exact WDF equation for free electrons in homogeneous electric and magnetic fields resulting in the same form as given by the collisionless Boltzmann transport equation (BTE). The methodology is then extended to the case of electrons described by an effective Hamiltonian corresponding to an arbitrary energy band function; the exact WDF equation results for the effective Hamiltonian case are shown to approximate the free electron results when taken to second order in the magnetic field. As a corollary, in these cases, it is shown that if the WDF is a wave packet, then the time rate of change of the electron quasimomentum is given by the Lorentz force. In treating the problem of Bloch electrons in a periodic potential in the presence of homogeneous electric and magnetic fields, the methodology for deriving the WDF reveals a multiband character due to the inherent nature of

  14. Establishment of a cell line from kidney of seabass, Lates calcarifer (Bloch

    Directory of Open Access Journals (Sweden)

    Phromkunthong, W.

    2003-01-01

    Full Text Available Primary cell culture from caudal fin and kidney of seabass (Lates calcarifer Bloch using tissue explant method were cultured in three different medias with various salt concentrations. Only seabass kidney (SK cells grew well in Leibovitze's-15 medium containing 8 g/l of NaCl supplemented with 10 % fetal bovine serum at an optimum temperature of 25 oC. Over a period of 24 months, SK cells were subcultured over than 75 passages and exhibited epithelial-like cells. The chromosome number of SK cells was 42. The cells were found to be free from bacterial, fungal and mycoplasma contamination. Seabass cells can be kept at -80 oC and/or in liquid nitrogen (-196 oC for at least 24 months with a survival rate of 83.20 and 74.50 %, respectively. Nine fish viruses were tested for their infectivity and this SK cells were susceptible to sand goby virus (SGV, chub reovirus (CRV, snake-head rhabdovirus (SHRV, red seabream iridovirus (RSIV, seabass iridovirus (SIV and grouper iridovirus-2 (GIV-2.

  15. Exact solutions to the fractional time-space Bloch-Torrey equation for magnetic resonance imaging

    Science.gov (United States)

    Bueno-Orovio, Alfonso; Burrage, Kevin

    2017-11-01

    The quantification of anomalous diffusion is increasingly being recognised as an advanced modality of analysis for the evaluation of tissue microstructure in magnetic resonance imaging (MRI). One powerful framework to account for anomalous diffusion in biological and structurally heterogeneous tissues is the use of diffusion operators based on fractional calculus theory, which generalises the physical principles of standard diffusion in homogeneous media. However, their non-locality makes analytical solutions often unavailable, limiting the applicability of these modelling and analysis techniques. In this paper, we derive compact analytical signal decays for practical MRI sequences in the anisotropic fractional Bloch-Torrey setting, as described by the space fractional Laplacian and importantly the time Caputo derivative. The attained solutions convey relevant characteristics of MRI in biological tissues not replicated by standard diffusion, including super-diffusive and sub-diffusive regimes in signal decay and the diffusion-driven incomplete refocusing of spins at the end of the sequence. These results may therefore have significant implications for advancing the current interpretation of MRI, and for the estimation of tissue properties based on exact solutions to underlying diffusive processes.

  16. A Bloch-based procedure for dispersion analysis of lattices with periodic time-varying properties

    Science.gov (United States)

    Vila, Javier; Pal, Raj Kumar; Ruzzene, Massimo; Trainiti, Giuseppe

    2017-10-01

    We present a procedure for the systematic estimation of the dispersion properties of linear discrete systems with periodic time-varying coefficients. The approach relies on the analysis of a single unit cell, making use of Bloch theorem along with the application of a harmonic balance methodology over an imposed solution ansatz. The solution of the resulting eigenvalue problem is followed by a procedure that selects the eigen-solutions corresponding to the ansatz, which is a plane wave defined by a frequency-wavenumber pair. Examples on spring-mass superlattices demonstrate the effectiveness of the method at predicting the dispersion behavior of linear elastic media. The matrix formulation of the problem suggests the broad applicability of the proposed technique. Furthermore, it is shown how dispersion can inform about the dynamic behavior of time-modulated finite lattices. The technique can be extended to multiple areas of physics, such as acoustic, elastic and electromagnetic systems, where periodic time-varying material properties may be used to obtain non-reciprocal wave propagation.

  17. Abner Doubleday, Marc Bloch, and the cultural significance of baseball in rural America.

    Science.gov (United States)

    Vaught, David

    2011-01-01

    In 1907 baseball's promoters decreed that Civil War hero Abner Doubleday created the game in the village of Cooperstown, New York, in 1839. Baseball thus acquired a distinctly rural American origin and a romantic pastoral appeal. Skeptics have since presented irrefutable evidence that America's pastime was neither born in the United States nor was a product of rural life. But in their zeal to debunk the myth of baseball's rural beginnings, historians have fallen prey to what Annales School founder Marc Bloch famously called the "idol of origins," and all but neglected the very real phenomenon of rural baseball itself. The claim that baseball has always been "a city game for city men" does not stand up to empirical scrutiny anymore than the Doubleday myth itself, as this address demonstrates with three case studies -- Cooperstown in the 1830s, Davisville, California, in the 1880s, and Milroy, Minnesota, in the 1950s. Baseball may have been a source of rural nostalgia for city people, but it was the sport of choice for farmers and a powerful cultural agent.

  18. Photonic lattices in organic microcavities: Bloch states and control of lasing

    Science.gov (United States)

    Mischok, Andreas; Brückner, Robert; Fröb, Hartmut; Lyssenko, Vadim G.; Leo, Karl

    2015-09-01

    Organic microcavities comprising the host:guest emitter system Alq3:DCM offer an interesting playground to experimentally study the dispersion characteristics of laterally patterned microlasers due to the broad emission spectrum and large oscillator strength of the organic dye. By structuring of metallic or dielectric sublayers directly on top of the bottom mirror, we precisely manipulate the mode structure and influence the coherent emission properties of the device. Embedding silver layers into a microcavity leads to an interaction of the optical cavity-state in the organic layer and the neighboring metal which red-shifts the cavity resonance, creating a Tamm-plasmon-polariton state. A patterning of the metal can in turn be exploited to fabricate deep photonic wells of micron-size, efficiently confining light in lateral direction. In periodic arrays of silver wires, we create a Kronig-Penney-like optical potential in the cavity and in turn observe optical Bloch states spanning over several photonic wires. We modify the Kronig-Penney theory to analytically describe the full far-field emission dispersion of our cavities and show the emergence of either zero- , π-, or 2π- phase-locking in the system. By investigating periodic SiO2 patterns, we experimentally observe stimulated emission from the ground and different excited discrete states at room temperature and are able to directly control the laser emission from both extended and confined modes of the photonic wires at room-temperature.

  19. Effects of the projectile electronic structure on Bethe-Bloch stopping parameters for Ag

    Energy Technology Data Exchange (ETDEWEB)

    Moussa, D., E-mail: djamelmoussa@gmail.co [USTHB, Faculte de Physique, B.P. 32, 16111 Bab-Ezzouar, Algiers (Algeria); Damache, S. [Division de Physique, CRNA, 02 Bd. Frantz Fanon, B.P. 399 Alger-gare, Algiers (Algeria); Ouichaoui, S., E-mail: souichaoui@gmail.co [USTHB, Faculte de Physique, B.P. 32, 16111 Bab-Ezzouar, Algiers (Algeria)

    2010-06-15

    Energy losses of protons and alpha particles in silver have been accurately measured under the same experimental conditions over the velocity range E{sub lab}=(0.192-2.595) MeV/amu using the transmission method. Deduced S(E) stopping powers are compared to most accurate ones from the literature, to values generated by the SRIM-2008 computer code and to ICRU-49 compilation. They were analyzed in the framework of modified Bethe-Bloch theory for extracting Ag target mean excitation and ionization potential, I, and Barkas effect parameter, b. Values of (466{+-}5) eV and 1.20{+-}0.01 for these two parameters were inferred from the proton S(E) data while the alpha particle data yielded values of (438{+-}4) eV and 1.38{+-}0.01, respectively. The (I, b) stopping parameters thus exhibit opposite variations as the projectile charge increases, similarly as we have found previously for nickel . This can be ascribed only to an effect of the projectile electronic structure at low velocities. The obtained results are discussed in comparison to previous ones reported in the literature.

  20. DEVELOPMENTS OF DIGESTIVE TRACT IN LARVAE OF CLIMBING PERCH, Anabas testudineus (Bloch

    Directory of Open Access Journals (Sweden)

    Yulintine Yulintine

    2010-12-01

    Full Text Available Climbing perch, Anabas testudineus (Bloch is a potential species for aquaculture in Kalimantan, Indonesia and belongs to Anabantidae family. The development of its digestive tract was evaluated on larvae reared under culture conditions of 28oC-30oC, from hatching to 30 days after hatching using histological and morphological methods. The larvae were kept in six 100-L tanks. They were fed with rotifers and microalgae from day 2nd after hatching to day 10th; Artemia nauplii from day 7th to day 15th; Artemia meta-nauplii from day 15th to day 20th; and Tubifex worm from day 20th onwards. The development of digestive tract in climbing perch followed the general pattern described for other species. Shortly after hatching, its digestive system was found to be consisted of an undifferentiated straight tube laying dorsally to the yolk sac. At first feeding (day 2nd, both mouth and anus had opened and the yolk sac was partially absorbed. On day 3, the digestive tract was fully differentiated into buccopharynx, esophagus, intestine and rectum. The two pyloric caeca appeared on day 25th after hatching, indicating the transition from larval to juvenile stage and acquisition of an adult type of digestion.

  1. The peripheral olfactory organ in the Greenland shark Somniosus microcephalus (Bloch and Schneider, 1801

    Directory of Open Access Journals (Sweden)

    Laura Ghigliotti

    2015-11-01

    Full Text Available The Greenland shark Somniosus microcephalus (Bloch and Schneider, 1801 is the largest predatory fish in Arctic waters. The socio-economic significance of Greenland shark is demonstrated by its impact on the fishing cultures in Greenland, Scandinavia and Iceland for centuries. The fundamental biology and ecological role of Greenland shark, on the other hand, is virtually unknown. Although knowledge of its life history is limited, increasing evidence indicates that the Greenland shark may undertake long-distance migrations and perform vertical movements from the surface to the deep sea. It is an omnivorous species feeding on carrion and a wide variety of pelagic and bottom-dwelling organisms ranging from invertebrates to mammals, and including active species such as fishes and seals. Accordingly, Greenland shark should be recognized as a top predator, with a strong potential to influence the trophic dynamics of the Arctic marine ecosystem. The sensory biology of Greenland shark is scarcely studied, and considering the importance of olfaction in chemoreception, feeding and other behavioral traits, we examined the architecture of the peripheral olfactory organ where olfactory cues are received from the environment – the olfactory rosette. The structural organization of the olfactory rosette, in terms of histological features of the sensory epithelium, number of primary lamellae and total sensory surface area, provides a first proxy of the olfactory capability of Greenland shark. Based on own results and published studies, the overall morphology of the olfactory rosette is viewed in context of the functional and trophic ecology among other elasmobranch species.

  2. Emergence of quasiparticle Bloch states in artificial crystals crafted atom-by-atom

    Directory of Open Access Journals (Sweden)

    Jan Girovsky, Jose L. Lado, Floris E. Kalff, Eleonora Fahrenfort, Lucas J. J. M. Peters, Joaquín Fernández-Rossier, Alexander F. Otte

    2017-06-01

    Full Text Available The interaction of electrons with a periodic potential of atoms in crystalline solids gives rise to band structure. The band structure of existing materials can be measured by photoemission spectroscopy and accurately understood in terms of the tight-binding model, however not many experimental approaches exist that allow to tailor artificial crystal lattices using a bottom-up approach. The ability to engineer and study atomically crafted designer materials by scanning tunnelling microscopy and spectroscopy (STM/STS helps to understand the emergence of material properties. Here, we use atom manipulation of individual vacancies in a chlorine monolayer on Cu(100 to construct one- and two-dimensional structures of various densities and sizes. Local STS measurements reveal the emergence of quasiparticle bands, evidenced by standing Bloch waves, with tuneable dispersion. The experimental data are understood in terms of a tight-binding model combined with an additional broadening term that allows an estimation of the coupling to the underlying substrate.

  3. Differential chromosomal markers between sympatric karyomorphs of the fish Hoplias malabaricus (Bloch, 1794 (Characiformes: Erythrinidae

    Directory of Open Access Journals (Sweden)

    Renata Rosa

    2010-12-01

    Full Text Available Cytogenetic analyses were performed on Hoplias malabaricus (Bloch, 1794 from the Taquari River, Parana River drainage, revealing two sympatric karyomorphs. One karyomorph was characterized by 2n = 40 m/sm and 2n = 39 m/sm chromosomes for females and males, respectively, and an X1X1X2X2/X1X2Y sex chromosome system. In the second karyomorph, specimens showed 2n = 42 m/sm chromosomes, without sex-related heteromorphism. Both karyomorphs were characterized by a distribution of heterochromatin in the pericentromeric and telomeric regions. In addition to the differences in the diploid numbers and the sex chromosomes, the GC-rich sites and the nucleolar organizer regions also showed clear differences between the karyomorphs. Coupled with the occurrence of unique chromosomal features within each karyomorph, the fact that hybrids have not been identified in the sampled population provides additional support of the existence of a species complex in H. malabaricus.

  4. The snakehead Channa asiatica accumulates alanine during aerial exposure, but is incapable of sustaining locomotory activities on land through partial amino acid catabolism.

    Science.gov (United States)

    Chew, Shit F; Wong, Mei Y; Tam, Wai L; Ip, Yuen K

    2003-02-01

    The freshwater snakehead Channa asiatica is an obligatory air-breather that resides in slow-flowing streams and in crevices near riverbanks in Southern China. In its natural habitat, it may encounter bouts of aerial exposure during the dry seasons. In the laboratory, the ammonia excretion rate of C. asiatica exposed to terrestrial conditions in a 12 h:12 h dark:light regime was one quarter that of the submerged control. Consequently, the ammonia contents in the muscle, liver and plasma increased significantly, and C. asiatica was able to tolerate quite high levels of ammonia in its tissues. Urea was not the major product of ammonia detoxification in C. asiatica, which apparently did not possess a functioning ornithine urea cycle. Rather, alanine increased fourfold to 12.6 micromol g(-1) in the muscle after 48 h of aerial exposure. This is the highest level known in adult teleosts exposed to air or an ammonia-loading situation. The accumulated alanine could account for 70% of the deficit in ammonia excretion during this period, indicating that partial amino acid catabolism had occurred. This would allow the utilization of certain amino acids as energy sources and, at the same time, maintain the new steady state levels of ammonia in various tissues, preventing them from rising further. There was a reduction in the aminating activity of glutamate dehydrogenase from the muscle and liver of specimens exposed to terrestrial conditions. Such a phenomenon has not been reported before and could, presumably, facilitate the entry of alpha-ketoglutarate into the Krebs cycle instead of its amination to glutamate, as has been suggested elsewhere. However, in contrast to mudskippers, C. asiatica was apparently unable to reduce the rates of proteolysis and amino acid catabolism, because the reduction in nitrogenous excretion during 48 h of aerial exposure was completely balanced by nitrogenous accumulation in the body. Alanine accumulation also occurred in specimens exposed to

  5. Offshore Habitat Preference of Overwintering Juvenile and Adult Black Sea Bass, Centropristis striata, and the Relationship to Year-Class Success.

    Directory of Open Access Journals (Sweden)

    Alicia S Miller

    Full Text Available Black sea bass (Centropristis striata migrations are believed to play a role in overwinter survival and connectivity between juvenile and adult populations. This study investigated oceanographic drivers of winter habitat choice and regional differences between populations of juvenile and adult black sea bass. Trends in cohort strength, as a result of juvenile survival, were also identified. Oceanographic and fisheries survey data were analyzed using generalized additive models. Among the oceanographic variables investigated, salinity was the main driver in habitat selection with an optimal range of 33-35 practical salinity units (PSU for both juveniles and adults. Preferred temperature ranges varied between juveniles and adults, but held a similar minimum preference of >8°C. Salinity and temperature ranges also differed by regions north and south of Hudson Canyon. Shelf water volume had less of an effect than temperature or salinity, but showed an overall negative relationship with survey catch. The effect of winter conditions on juvenile abundance was also observed across state and federal survey index trends. A lack of correlation observed among surveys in the fall paired with a strong correlation in the spring identifies the winter period as a factor determining year-class strength of new recruits to the population. A rank order analysis of spring indices identified three of the largest year classes occurring during years with reduced shelf water volumes, warmer winter shelf waters, and a 34 PSU isohaline aligned farther inshore. While greater catches of black sea bass in the northwest Atlantic Ocean remain south of Hudson Canyon, the species' range has expanded north in recent years.

  6. An Update on the Invasion of Weakfish Cynoscion regalis (Bloch & Schneider, 1801 (Actinopterygii: Sciaenidae into Europe

    Directory of Open Access Journals (Sweden)

    Pedro Morais

    2017-10-01

    Full Text Available New information on weakfish introduction vectors, its invasive status, distribution, and use as a fishing resource arose after the publication of “The transatlantic introduction of weakfish Cynoscion regalis (Bloch & Schneider, 1801 (Sciaenidae, Pisces into Europe” by Morais and Teodósio (2016. Currently, the first known report of weakfish in Europe dates back to September 2009, with a specimen captured in the Schelde estuary (Belgium/The Netherlands. This fact suggests that weakfish could have been introduced into Europe via multiple and independent ballast water introduction events, and not through a point-source introduction event with subsequent dispersion as previously hypothesized. It is also unlikely that Schelde weakfish migrated southwards to colonize Iberian aquatic ecosystems. Weakfish have established a population in the Gulf of Cádiz region and have already reached an invasive status in the Sado estuary (Portugal. Weakfish were also captured in several other locations along the Portuguese coast, including the Tagus and Mira estuaries at least since 2013 or 2014, and the Ria Formosa lagoon in 2017. Tagus anglers caught weakfish specimens of ~1 kg and ~40 cm in November 2016, which corresponds to fish of 3+ years of age in the native range. The presence of weakfish in the Tagus estuary is still fairly unknown to local anglers. Sado weakfish has already been sold in local fish markets in southern Portugal for 3 to 10 € kg−1. However, we consider that the weakfish sale price is underrated in comparison with other wild species (e.g., meagre, seabass, gilthead seabream. Increasing sale price will convince fishers to use weakfish as a new fishing resource; however, it is necessary to promote the species among consumers and evaluate consumers’ preference in respect to other species. A putative biological threat might turn into a new valuable fishing resource by implementing adequate management solutions.

  7. Nutritional evaluation of the moonfish Mene maculata (Bloch & Schneider, 1801 from Parangipettai, southeast coast of India

    Directory of Open Access Journals (Sweden)

    Palanivel Bharadhirajan

    2014-01-01

    Full Text Available Objective: To assess the nutritions in Mene maculata (Bloch & Schneider, 1801 (M. maculata. Methods: Fishes (14-16 cm were obtained from the landings at Parangipettai for the evaluation of biochemical composition. The present study deals with biochemical composition such as protein, carbohydrate, lipid, amino acids fatty acids, vitamins and minerals which were evaluated in the moonfish. Results: The results of proximate composition in M. maculata showed that the percentage of protein was high in the tissue (23.16%, followed by the carbohydrate (1.3% and lipid (2.62%. Totally 20 essential and nonessential amino acids were present at the rate of 46.72% and 43.91%. In the analysis, the fatty acid profile by gas chromatography revealed the presence of higher amount of saturated fatty acid (palmitic acid 22.17% than monounsaturated fatty acid (oleic acid 14.51% and polyunsaturated fatty acid (alpha linolenic acid 16.07%. Vitamins were detected in M. maculata. Among them, vitamin A was found in higher levels (124.5 mg/g, whereas vitamin B6 was noticed as lower levels (0.34 mg/g. In the present study, totally 5 macro minerals and 2 trace minerals were reported. The macro mineral calcium (156.7 mg/g was found at the highest level and other minerals such as sodium (31.98 mg/g, potassium (21.33 mg/g, copper (1.43 mg/g and magnesium (0.341 mg/g were also detected in the moonfish. Conclusions: The result showed that the moonfish M. maculata tissue is a valuable food recipe for human consumption, due to its high quality protein and well-balanced amino acids.

  8. Several Growth Characteristics of an Invasive Cyprinid Fish (Carassius gibelio Bloch, 1782

    Directory of Open Access Journals (Sweden)

    Sait BULUT

    2013-05-01

    Full Text Available Age composition, length-weight relationships, growth, and condition factors of the gibel carp (Carassius gibelio Bloch, 1782 were determined using specimens collected from Seyitler Reservoir between July 2005 to June 2006. A total of 149 gibel carp were observed and examined. The age composition of the samples ranged between I and VII years of age. It has been determined than 82.55% of the obtained samples are comprised of females, 16.11% is comprised of males and 1.34% is comprised of immature. The population is dominated by females able to reproduce gynogenetically. The mean fork lengths and mean weights of the population were 14.8-32.5 cm and 43.1-807.3 g respectively. The length-weight relation were calculated as W = 0.0696 L2.132, r=0.838 for females, for males W = 0.2942 L2.6417 r=0.784 and W = 0.0274 L2.9382, r=0.813 for all samples. The mean Fulton Condition Factor was calculated as 2.342 for females, 2.064 for males and 2.276 for all samples. Age-length and age-weight relations were determined according to von Bertalanffy growth equation formula. Growth parameters of the population were Lt = 48.09 [1-e-0.093(t+0.29], and Wt=2323.62 [1-e-0.093(t+0.29]2.9382. The growth performance index value (Ø´ was computed as 5.37 for all specimens.

  9. Stability and convergence of an implicit numerical method for the space and time fractional Bloch-Torrey equation.

    Science.gov (United States)

    Yu, Qiang; Liu, Fawang; Turner, Ian; Burrage, Kevin

    2013-05-13

    Fractional-order dynamics in physics, particularly when applied to diffusion, leads to an extension of the concept of Brownian motion through a generalization of the Gaussian probability function to what is termed anomalous diffusion. As magnetic resonance imaging is applied with increasing temporal and spatial resolution, the spin dynamics is being examined more closely; such examinations extend our knowledge of biological materials through a detailed analysis of relaxation time distribution and water diffusion heterogeneity. Here, the dynamic models become more complex as they attempt to correlate new data with a multiplicity of tissue compartments, where processes are often anisotropic. Anomalous diffusion in the human brain using fractional-order calculus has been investigated. Recently, a new diffusion model was proposed by solving the Bloch-Torrey equation using fractional-order calculus with respect to time and space. However, effective numerical methods and supporting error analyses for the fractional Bloch-Torrey equation are still limited. In this paper, the space and time fractional Bloch-Torrey equation (ST-FBTE) in both fractional Laplacian and Riesz derivative form is considered. The time and space derivatives in the ST-FBTE are replaced by the Caputo and the sequential Riesz fractional derivatives, respectively. Firstly, we derive an analytical solution for the ST-FBTE in fractional Laplacian form with initial and boundary conditions on a finite domain. Secondly, we propose an implicit numerical method (INM) for the ST-FBTE based on the Riesz form, and the stability and convergence of the INM are investigated. We prove that the INM for the ST-FBTE is unconditionally stable and convergent. Finally, we present some numerical results that support our theoretical analysis.

  10. Antes, desde y para el exilio. Herencia de esta época (1935/1962 de Ernst Bloch

    Directory of Open Access Journals (Sweden)

    Salmerón Infante, Miguel

    2009-10-01

    Full Text Available The first edition of Erbschaft dieser Zeit was published in Zurich in 1935, during Ernst Bloch’s five-year period of emigration from Nazi-Germany in various European capitals before his final emigration to America for ten years in 1938. In this book Bloch made a courageous stand in defence of the artistic avant-garde against the dogmatic advocates of socialist realism. His particularly adversary was Georg Lukács. But of course one of the most fascinating aspects of the book is that is also reads as a contemporary observation of the rise of the Nazis. Erbschaft is undoubtedly the major work of Weimar Germany Exile.La primera edición de Erbschaft dieser Zeit fue publicada en 1935 en Zurich, durante la emigración de Ernst Bloch de la Alemania nazi por un período de cinco años en el que residió en varias capitales europeas antes de su marcha definitiva a América en 1938, donde vivió diez años. En este libro Bloch hace una encorajinada defensa de la vanguardia artística contra los abogados del realismo socialista. Su adversario específico era Georg Lukács. Pero sin duda alguna uno de los aspectos más fascinantes de este libro es que puede leerse como una observación contemporánea de la ascensión al poder de los nazis. Erbschaft es indudablemente la obra clave del exilio de la Alemania de Weimar.

  11. Web-based description of the space radiation environment using the Bethe-Bloch model

    Science.gov (United States)

    Cazzola, Emanuele; Calders, Stijn; Lapenta, Giovanni

    2016-01-01

    Space weather is a rapidly growing area of research not only in scientific and engineering applications but also in physics education and in the interest of the public. We focus especially on space radiation and its impact on space exploration. The topic is highly interdisciplinary, bringing together fundamental concepts of nuclear physics with aspects of radiation protection and space science. We give a new approach to presenting the topic by developing a web-based application that combines some of the fundamental concepts from these two fields into a single tool that can be used in the context of advanced secondary or undergraduate university education. We present DREADCode, an outreach or teaching tool to rapidly assess the current conditions of the radiation field in space. DREADCode uses the available data feeds from a number of ongoing space missions (ACE, GOES-13, GOES-15) to produce a first order approximation of the radiation dose an astronaut would receive during a mission of exploration in deep space (i.e. far from the Earth’s shielding magnetic field and from the radiation belts). DREADCode is based on an easy-to-use GUI interface available online from the European Space Weather Portal (www.spaceweather.eu/dreadcode). The core of the radiation transport computation to produce the radiation dose from the observed fluence of radiation observed by the spacecraft fleet considered is based on a relatively simple approximation: the Bethe-Bloch equation. DREADCode also assumes a simplified geometry and material configuration for the shields used to compute the dose. The approach is approximate and sacrifices some important physics on the altar of rapid execution time, which allows a real-time operation scenario. There is no intention here to produce an operational tool for use in space science and engineering. Rather, we present an educational tool at undergraduate level that uses modern web-based and programming methods to learn some of the most important

  12. KONSERVASI GENETIK IKAN BETOK (Anabas testudineus Bloch 1792 DI PERAIRAN RAWA, KALIMANTAN SELATAN

    Directory of Open Access Journals (Sweden)

    Slamat Slamat

    2016-05-01

    Full Text Available Penelitian ini dilakukan dengan menggunakan sample ikan betok (Anabas testudineus Bloch 1972 yang berasal dari perairan rawa Kalimantan Selatan, dengan tujuan untuk mendeskripsikan keragaman  genetik dan aspek konservasinya dengan metode amplifikasi mtDNA. Proses amplifikasi mtDNA ikan betok terjadi di daerah D Loop.  Hasil analisis mt-DNA D Loop ikan betok menunjukkan bahwa, analisis keseimbangan populasi Hardy-Weinberg  berkisar antara 0,02 - 0,09, sedangkan haplotipe tertinggi terdapat pada rawa monoton (0,9384, kemudian tadah hujan (0,7111 dan pasang surut (0,6.  Heterozigositas ditemukan unik pada populasi rawa monoton (BAAAA dan rawa pasang surut (BAACA dan umum di temukan di ketiga ekosistem rawa (AAABA.  Ikan betok di bagi menjadi dua stok populasi yaitu populasi rawa monoton dan pasang surut serta stok tadah hujan.  Konsep utama dalam konservasi genetik adalah fitness population dimana populasi dipertahankan minimal 500 ekor/kawasan. Untuk meningkatkan keragaman genetik ikan betok, dilakukan dengan cara introduksi individu-individu baru yang memiliki keragaman genetik yang lebih tinggi kedalam populasi lokal, restocking dan membuat kawasan suaka yang dilindungi oleh Dinas Perikanan setempat bersama-sama dengan masyarakat di sekitar perairan rawa tersebut.   The research was conducted using climbing perch samples originated from the swampy waters of the southern Borneo, and the objektive of this study to investigate the genetic diversity and the conservation aspect using mtDNA amplification method.  mtDNA amplification process occurs in the D Loop region.  The results of the analysis of D-Loop mtDNA of climbing perch showed that, the analysis of Hardy-Weinberg equilibrium population ranged from 0.02 to 0.09, while the highest haplotypes found in swamp bogs (monotonic (0.9384 then rainfed (0.7111 and tides (0.6. Heterozygosity was found uniquely in the swamp monotonic population (BAAAA and marsh tides (BAACA and common in all

  13. Plasmonic Photonic-Crystal Slabs: Visualization of the Bloch Surface Wave Resonance for an Ultrasensitive, Robust and Reusable Optical Biosensor

    Directory of Open Access Journals (Sweden)

    Alexander V. Baryshev

    2014-12-01

    Full Text Available A one-dimensional photonic crystal (PhC with termination by a metal film—a plasmonic photonic-crystal slab—has been theoretically analyzed for its optical response at a variation of the dielectric permittivity of an analyte and at a condition simulating the molecular binding event. Visualization of the Bloch surface wave resonance (SWR was done with the aid of plasmon absorption in a dielectric/metal/dielectric sandwich terminating a PhC. An SWR peak in spectra of such a plasmonic photonic crystal (PPhC slab comprising a noble or base metal layer was shown to be sensitive to a negligible variation of refractive index of a medium adjoining to the slab. As a consequence, the considered PPhC-based optical sensors exhibited an enhanced sensitivity and a good robustness in comparison with the conventional surface-plasmon and Bloch surface wave sensors. The PPhC biosensors can be of practical importance because the metal layer is protected by a capping dielectric layer from contact with analytes and, consequently, from deterioration.

  14. Full-angle Negative Reflection with An Ultrathin Acoustic Gradient Metasurface: Floquet-Bloch Modes Perspective and Experimental Verification

    KAUST Repository

    Liu, Bingyi

    2017-07-01

    Metasurface with gradient phase response offers new alternative for steering the propagation of waves. Conventional Snell\\'s law has been revised by taking the contribution of local phase gradient into account. However, the requirement of momentum matching along the metasurface sets its nontrivial beam manipulation functionality within a limited-angle incidence. In this work, we theoretically and experimentally demonstrate that the acoustic gradient metasurface supports the negative reflection for full-angle incidence. The mode expansion theory is developed to help understand how the gradient metasurface tailors the incident beams, and the full-angle negative reflection occurs when the first negative order Floquet-Bloch mode dominates. The coiling-up space structures are utilized to build desired acoustic gradient metasurface and the full-angle negative reflections have been perfectly verified by experimental measurements. Our work offers the Floquet-Bloch modes perspective for qualitatively understanding the reflection behaviors of the acoustic gradient metasurface and enables a new degree of the acoustic wave manipulating.

  15. Mathematical Development and Computational Analysis of Harmonic Phase-Magnetic Resonance Imaging (HARP-MRI) Based on Bloch Nuclear Magnetic Resonance (NMR) Diffusion Model for Myocardial Motion.

    Science.gov (United States)

    Dada, Michael O; Jayeoba, Babatunde; Awojoyogbe, Bamidele O; Uno, Uno E; Awe, Oluseyi E

    2017-09-13

    Harmonic Phase-Magnetic Resonance Imaging (HARP-MRI) is a tagged image analysis method that can measure myocardial motion and strain in near real-time and is considered a potential candidate to make magnetic resonance tagging clinically viable. However, analytical expressions of radially tagged transverse magnetization in polar coordinates (which is required to appropriately describe the shape of the heart) have not been explored because the physics required to directly connect myocardial deformation of tagged Nuclear Magnetic Resonance (NMR) transverse magnetization in polar geometry and the appropriate harmonic phase parameters are not yet available. The analytical solution of Bloch NMR diffusion equation in spherical geometry with appropriate spherical wave tagging function is important for proper analysis and monitoring of heart systolic and diastolic deformation with relevant boundary conditions. In this study, we applied Harmonic Phase MRI method to compute the difference between tagged and untagged NMR transverse magnetization based on the Bloch NMR diffusion equation and obtained radial wave tagging function for analysis of myocardial motion. The analytical solution of the Bloch NMR equations and the computational simulation of myocardial motion as developed in this study are intended to significantly improve healthcare for accurate diagnosis, prognosis and treatment of cardiovascular related deceases at the lowest cost because MRI scan is still one of the most expensive anywhere. The analysis is fundamental and significant because all Magnetic Resonance Imaging techniques are based on the Bloch NMR flow equations.

  16. A redescription of the South American Catfish Loricariichthys maculatus (Bloch, 1794), with designation of the lectotype and restriction of its type locality (Pisces, Siluriformes, Loricariidae)

    NARCIS (Netherlands)

    Isbrücker, I.J.H.

    1971-01-01

    The type species of the genus Loricariichthys Bleeker, 1862, Loricariichthys maculatus (Bloch, 1794), is redescribed from two syntypes, one of which is designated the lectotype. The same specimen is also designated the neotype for Plecostomus cataphracta Gronovius (ed. Gray), 1854 (non Loricaria

  17. Pisces, Perciformes, Eleotridae, Dormitator maculatus (Bloch, 1792: Distribution extension for Patos-Mirim lagoon system, state of Rio Grande do Sul, Brazil.

    Directory of Open Access Journals (Sweden)

    Volcan, M. V.

    2010-01-01

    Full Text Available We present here the record of Dormitator maculatus (Bloch, 1792 to the Patos-Mirim lagoon system, RioGrande do Sul, Brazil. This is also the southernmost occurrence in South America, extending species range ca. 150 km fromthe previously known localities.

  18. Composição química e antinutrientes presentes nas amêndoas cruas e torradas de chicha (Sterculia striata A. St. Hill & Naudin Chemical composition and antinutrients of raw and roasted chicha almonds (Sterculia striata A. St. Hill & Naudin

    Directory of Open Access Journals (Sweden)

    Aline Gomes de Moura e Silva

    2011-04-01

    Full Text Available OBJETIVO: Analisar os componentes químicos e antinutrientes antes e após torrefação da amêndoa de chichá da espécie Sterculia striata A. St. Hill & Naudin, oriunda de Corrente, Piauí. MÉTODOS: Foram realizadas análises: centesimal, perfil de ácidos graxos, antinutrientes (taninos, inibidor de tripsina, inibidor de amilase, lectina, fitatos, compostos fenólicos e atividade de peroxidase e polifenoloxidase. RESULTADOS: Os resultados da análise centesimal da amêndoa crua e torrada foram: lipídeos de 25,1% e 26,2%, carboidratos de 44,4% e 45,6%, proteína de 20,8% e 22,1%, cinzas de 3,7% e 4,0%, fibra alimentar total de 12,3% e 10,4%, respectivamente. Nas amêndoas cruas e torradas não foram encontradas lectinas, taninos, inibidores de tripsina e alfa-amilase. Verificou-se a ausência de peroxidase e polifenoloxidase e conteúdo de compostos fenólicos de 107,7mg/100g e 108,9mg/100g para amêndoas cruas e torradas, respectivamente. CONCLUSÃO: A torrefação realizada a 205°C por 11 minutos diminuiu o teor de fitatos de 10,6mg/g para 5,5mg/g. Por fim, as amêndoas de chichá, cruas e torradas, apresentam alto teor de proteínas, fibras, ácidos graxos monoinsaturados e saturados.OBJECTIVE: This study analyzed the chemical components and antinutrients present in raw and roasted chichá almonds from the species Sterculia striata A. St. Hill & Naudin harvested in Corrente, Piauí. METHODS: The following were determined: percent composition, fatty acid profile, antinutrients (tannins, trypsin inhibitor, amylase inhibitor, lectin, phytates, phenolic compounds and peroxidase and polyphenol oxidase activities. RESULTS: The percentage composition of the raw and lipid almonds were respectively: 25.1% and 26.2% fats, 44.4% and 45.6% carbohydrates, 20.8% and 22.1% protein, 3.7% and 4.0% ashes, and 12.3% and 10.4% total fiber. Neither raw nor roasted almonds contained lectins, tannins, trypsin inhibitors, alpha-amylase, peroxidase and

  19. A força da tradição: a persistência do antigo regime historiográfico na obra de Marc Bloch The power of tradition: the persistence of historic old regime in Marc Bloch's Oeuvre

    Directory of Open Access Journals (Sweden)

    Tiago de Melo Gomes

    2006-12-01

    Full Text Available Este artigo se foca na obra de Marc Bloch, em especial em seu livro tido como mais importante, A Sociedade Feudal (1939, argumentando que mesmo no trabalho de um dos mais importantes do século XX ainda é possível encontrar elementos associados a uma historiografia mais tradicional.This article is focused on Marc Bloch's oeuvre, especially in his so-called masterpiece, Feudal Society (1939, arguing that even in the work of one of the most important historians of the century, we can find important elements of the traditional historiography.

  20. El anacronismo en la historia: ¿error o posibilidad? A propósito de las reflexiones sobre el tiempo en Carlo Ginzburg, Marc Bloch y Georges Didi-Huberman

    National Research Council Canada - National Science Library

    María Eugenia Chaves Maldonado

    2016-01-01

      In his unfinished and posthumously published book Apologie pour l'histoire, Marc Bloch bestowed on future historians a seminal legacy of critical reflections on the concept of time as the object of historical analysis...

  1. Author Details

    African Journals Online (AJOL)

    Parasuraman, Aiya Subramani. Vol 7, No 2 (2017) - Articles Modulation of the innate immune responses in the striped snakehead murrel, Channa striata upon experimental infection with live and heat killed Aeromonas hydrophila. Abstract PDF. ISSN: 2218-6050. AJOL African Journals Online. HOW TO USE AJOL.

  2. Author Details

    African Journals Online (AJOL)

    Sekaran, Kalaivani Priyadarshini. Vol 7, No 2 (2017) - Articles Modulation of the innate immune responses in the striped snakehead murrel, Channa striata upon experimental infection with live and heat killed Aeromonas hydrophila. Abstract PDF. ISSN: 2218-6050. AJOL African Journals Online. HOW TO USE AJOL.

  3. Extraction, isolation and characterization of bioactive compounds from chloroform extract of Carica papaya seed and it's in vivo antibacterial potentiality in Channa punctatus against Klebsiella PKBSG14.

    Science.gov (United States)

    Ghosh, Subarna; Saha, Mandira; Bandyopadhyay, Probir Kumar; Jana, Monoranjan

    2017-10-01

    The relative efficacy of the isolated pure compound, extracted from Carica papaya seed has been tested against live fish, Channa punctatus infected with pathogenic strains of KlebsiellaPKBSG14 (gene bank accession no.KJ162158) at a dose of 0.75 CFU/ml in vivo. The isolated compound has been characterized by chromatography and mass spectroscopy studies using FTIR, 1HNMR and 13c NMR to identify as well as to determine the nature of the pure compound. This study revealed the extracted biological molecule is oleic acid, a long chained saturated fatty acid (LFAs) with a molecular formula C18H34O2. Later this compound was analyzed for its efficacy as an antibacterial agent in vivo through cytotoxicological and genotoxicological assays. A dose of 0.5 mg/kg and 1 mg/kg b.w of isolated pure oleic acid has been tested and it showed effective result in regard to DNA fragmentation, comet tail length and toxicity biomarkers like ROS generation. The results of in vivo studies showed similar effects on spleen cells with regard to cell viability by PI staining, cell cycle analysis and also Annexin-FITC assay. Thus, the overall results suggest that oleic acid increases drug bioavailability and thereby has a better chemo-preventive action against bacterial infection in vivo. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. A Bloch equation approach to intensity dependent optical spectra of light harvesting complex II: excitation dependence of light harvesting complex II pump-probe spectra.

    Science.gov (United States)

    Richter, Marten; Renger, Thomas; Knorr, Andreas

    2008-01-01

    On the basis of the recent progress in the resolution of the structure of the antenna light harvesting complex II (LHC II) of the photosystem II, we propose a microscopically motivated theory to predict excitation intensity-dependent spectra. We show that optical Bloch equations provide the means to include all 2( N ) excited states of an oligomer complex of N coupled two-level systems and analyze the effects of Pauli Blocking and exciton-exciton annihilation on pump-probe spectra. We use LHC Bloch equations for 14 Coulomb coupled two-level systems, which describe the S (0) and S (1) level of every chlorophyll molecule. All parameter introduced into the Hamiltonian are based on microscopic structure and a quantum chemical model. The derived Bloch equations describe not only linear absorption but also the intensity dependence of optical spectra in a regime where the interplay of Pauli Blocking effects as well as exciton-exciton annihilation effects are important. As an example, pump-probe spectra are discussed. The observed saturation of the spectra for high intensities can be viewed as a relaxation channel blockade on short time scales due to Pauli blocking. The theoretical investigation is useful for the interpretation of the experimental data, if the experimental conditions exceed the low intensity pump limit and effects like strong Pauli Blocking and exciton-exciton annihilation need to be considered. These effects become important when multiple excitations are generated by the pump pulse in the complex.

  5. STUDIES REGARDING THE INFLUENCE OF TOPSIN M 70 PU FUNGICIDE ON CARASSIUS AURATUS GIBELIO BLOCH L. 1758

    Directory of Open Access Journals (Sweden)

    Bogdan Mihai Udroiu

    2015-12-01

    Full Text Available The main objective of this study is to see how the metylthiophanate fungicide influences the energetic metabolism and the breathing rhythm at Carassius auratus gibelio Bloch L. 1758. Experimental samples were subjected to under-lethal concentrations of 3.75mg/l, 7.5mg/l, 15mg/l and 30mg/l methyl-thiophanate fungicide from 24 to 336 hours. The physiologic parameter with the highest growth rate was the oxygen consumption, which, at the concentration of 7.5mg/l grew by 40.3% in 6 hours, compared to the witness values, registering the value of 179.52 mg oxygen/l/h compared to 127.95 mg oxygen/l/h. Also, the breathing rhythm grew at the concentration of 7.5 mg/l by 24.76% in 6 hours, compared to the witness values. At the concentration of 30mg/l, both physiologic parameters decreased. So, after 6 hours, the oxygen consumption decrease up to 31.38% from the witness values, registering the value of 51.503mg oxygen/l/h compared to 164.09mg oxygen/l/h, and the breathing rhythm decreased to 84.3% compared to the witness martor.

  6. Magnetic susceptibility of Dirac fermions, Bi-Sb alloys, interacting Bloch fermions, dilute nonmagnetic alloys, and Kondo alloys

    Energy Technology Data Exchange (ETDEWEB)

    Buot, Felix A., E-mail: fbuot@gmu.edu [Computational Materials Science Center, George Mason University, Fairfax, VA 22030 (United States); TCSE Center, Spintronics Group, Physics Department, University of San Carlos, Talamban, Cebu 6000 (Philippines); C& LB Research Institute, Carmen, Cebu 6005 (Philippines); Otadoy, Roland E.S.; Rivero, Karla B. [TCSE Center, Spintronics Group, Physics Department, University of San Carlos, Talamban, Cebu 6000 (Philippines)

    2017-03-01

    Wide ranging interest in Dirac Hamiltonian is due to the emergence of novel materials, namely, graphene, topological insulators and superconductors, the newly-discovered Weyl semimetals, and still actively-sought after Majorana fermions in real materials. We give a brief review of the relativistic Dirac quantum mechanics and its impact in the developments of modern physics. The quantum band dynamics of Dirac Hamiltonian is crucial in resolving the giant diamagnetism of bismuth and Bi-Sb alloys. Quantitative agreement of the theory with the experiments on Bi-Sb alloys has been achieved, and physically meaningful contributions to the diamagnetism has been identified. We also treat relativistic Dirac fermion as an interband dynamics in uniform magnetic fields. For the interacting Bloch electrons, the role of translation symmetry for calculating the magnetic susceptibility avoids any approximation to second order in the field. The expressions for magnetic susceptibility of dilute nonmagnetic alloys give a firm theoretical foundation of the empirical formulas used in fitting experimental results. The unified treatment of all the above calculations is based on the lattice Weyl-Wigner formulation of discrete phase-space quantum mechanics. For completeness, the magnetic susceptibility of Kondo alloys is also given since Dirac fermions in conduction band and magnetic impurities exhibit Kondo effect.

  7. HÁBITOS ALIMENTARIOS DE LA MAYUPA (Sternopygus macrurus Bloch & Schneider, 1801 EN EL RÍO SINÚ, COLOMBIA

    Directory of Open Access Journals (Sweden)

    Javier Barrera-Chica

    2009-12-01

    Full Text Available Objetivo. Estudiar los hábitos alimentarios de la Mayupa (Sternopygus macrurus Bloch & Schneider, 1801 en el río Sinú, Colombia. Materiales y métodos. El contenido estomacal se evaluó con el coeficiente de vacuidad, grado de llenado, grado de digestión, frecuencia de ocurrencia, frecuencia numérica, gravimetría, indice de importancia relativa (IIR y la relación longitud intestinal (LI-longitud total (LT. Resultados. Solo pocos estómagos se encontraron vacíos (CV =6.9% y el 60.0% de las presas se encontraron frescas. Se identificaron cuatro ítems alimentarios: peces, crustáceos, material vegetal y otros. Peces fue el ítem más frecuente (76.9%, abundante (48.3%, con mayor composición por peso (81.9% y con mayor importancia relativa (63.2%. Conclusiones. Los resultados obtenidos permiten inferir que la Mayupa es un pez de hábitos alimentarios carnívoros, con preferencia por los peces.

  8. Experimental infection of Aphanomyces invadans and susceptibility in seven species of tropical fish

    Directory of Open Access Journals (Sweden)

    Seyedeh F. Afzali

    2015-09-01

    Full Text Available Aim: Epizootic ulcerative syndrome (EUS causes by aquatic oomycete fungus, Aphanomyces invadans is a dangerous fish disease of a wide range of fresh and brackish water, wild and farmed fish throughout the world. The objective of the present study was to determine the susceptibility of a number of tropical fish species to the EUS and compare the severity of infection between experimental groups. Materials and Methods: Snakehead, Channa striata (Bloch, 1793; snakeskin gourami, Trichopodus pectoralis (Regan, 1910; koi carp, Cyprinus carpio (Linnaeus, 1758; broadhead catfish, Clarias macrocephalus (Günther, 1864; goldfish, Carassius auratus (Linnaeus, 1758; climbing perch, Anabas testudineus (Bloch, 1792; and Nile tilapia, Oreochromis niloticus (Linnaeus, 1758 were challenged by intramuscular injection using zoospores of Aphanomyces invadans (NJM9701. The infected fish skins and muscles were examined for EUS histopathological characteristics, and the results on the severity of lesions and mortality were analyzed using SPSS program. Results: All zoospore-injected fish were shown to be susceptible to the EUS infection except Nile tilapia. Although, the general histopathological pattern was similar in the zoospore-injected group, but there were some variation in granulomatous reaction, that is the presence or absence of giant cells, and time of mortality were detected. The result of statistical analysis showed that there was a significant difference between species, (c2=145.11 and p<0.01. Conclusion: Gourami, koi carp, and catfish were demonstrated to be highly susceptible while goldfish and climbing perch were found to be moderately susceptible to the EUS infection. These findings suggested that the cellular response of fish to mycotic infection and granulomatous reaction varied in different fish species, which could not be an indicator of susceptibility or resistant to the EUS itself, although it was shown that the granulation rate and the level of

  9. Morphometric evaluation of the spermatogenesis in trahira Hoplias malabaricus (Bloch (Characiformes, Erythrinidae Avaliação morfométrica da espermatogênese da traíra Hoplias malabaricus (Bloch (Characiformes, Erythrinidae

    Directory of Open Access Journals (Sweden)

    Paula M. Bizzott

    2007-01-01

    Full Text Available The Erythrinidae trahira, Hoplias malabaricus (Bloch, 1794, is widespread throughout South America river basins. We determined Sertoli cell supporting capacity (ratio of primary spermatocytes: Sertoli cells and spermatids: Sertoli cells, meiotic index (ratio of spermatids: primary spermatocytes and the number of spermatogonial mitotic generations of this fish. The fish were captured in the Igarapava reservoir, Grande River, Alto Paraná River basin, Brazil. Testis fragments of three sexually mature trahiras were fixed in 5% buffered glutaraldehyde solution and embedded in glycol methacrylate. Serial sections of 2 and 3 µm in thickness were stained with 0.5% toluidine blue. Histological counts from cysts of primary spermatocytes and spermatids revealed, respectively, 326 ± 99 and 468 ± 73 nuclei of these cells. Sertoli cell supporting capacity was considerably higher for spermatids (113.3 ± 16:1 when compared to primary spermatocytes (71 ± 5:1. Between eight and ten spermatogonial generations were formed to give rise to primary spermatocytes. These values were within the generation range of those already found in freshwater teleosts of external fertilization. Correlation between the number of Sertoli cells and primary spermatocytes per cyst, and Sertoli cells and spermatids per cyst were statistically significant (p A traíra, Hoplias malabaricus (Bloch, 1794, da família Erythrinidae, encontra-se espalhada pelas bacias fluviais da América do Sul. Determinou-se a capacidade de suporte das células de Sertoli (espermatócitos primários: células de Sertoli e espermátides: células de Sertoli, índice meiótico (espermátides: espermatócitos primário e o número de gerações mitóticas de espermatogônias desse peixe. Os indivíduos foram capturados no reservatório de Igarapava, rio Grande, bacia do Alto Paraná, Brasil. Fragmentos dos testículos de três traíras sexualmente maduras foram fixados em glutaraldeído a 5%, e inclu

  10. Pemaparan merkuri nitrat (Hg (No32 dengan konsentrasi berbeda pada jaringan hati benih ikan kakap putih (Lates calcarifer Bloch: tinjauan histologi

    Directory of Open Access Journals (Sweden)

    Munawar Khalil

    2013-12-01

    Full Text Available Tujuan penelitian ini adalah untuk mempelajari pengaruh logam berat merkuri nitrat (Hg(NO32 pada struktur histologis hati benih ikan kakap putih (Lates calcarifer Bloch yang dipelihara di air laut. Analisis struktur jaringan hati dilakukan melalui teknik histologi. Hasil penelitian menunjukkan bahwa Hg(NO32 memberikan efek negatif pada hati benih ikan. Pada jaringan hati, (Hg(NO32 menyebabkan kerusakan atrophy, necrosis, lapisan antar sel hati berpisah, perlemakan hati, pembengkakan sel yang tidak beraturan, degenerasi pada vacuola, terbentuknya ruang antar sel, hepatitis, sirrhosis dan terdapatnya akumulasi logam berat Hg(NO32 dalam jaringan hati.

  11. Electron-spin relaxation in bulk III-V semiconductors from a fully microscopic kinetic spin Bloch equation approach

    Science.gov (United States)

    Jiang, J. H.; Wu, M. W.

    2009-03-01

    Electron spin relaxation in bulk III-V semiconductors is investigated from a fully microscopic kinetic spin Bloch equation approach where all relevant scatterings, such as, the electron-nonmagnetic-impurity, electron-phonon, electron-electron, electron-hole, and electron-hole exchange (the Bir-Aronov-Pikus mechanism) scatterings are explicitly included. The Elliott-Yafet mechanism is also fully incorporated. This approach offers a way toward thorough understanding of electron spin relaxation both near and far away from the equilibrium in the metallic regime. The dependences of the spin relaxation time on electron density, temperature, initial spin polarization, photo-excitation density, and hole density are studied thoroughly with the underlying physics analyzed. We find that these dependences are usually qualitatively different in the nondegenerate and degenerate regimes. In contrast to the previous investigations in the literature, we find that: (i) In n -type materials, the Elliott-Yafet mechanism is less important than the D’yakonov-Perel’ mechanism, even for the narrow band-gap semiconductors such as InSb and InAs. (ii) The density dependence of the spin relaxation time is nonmonotonic and we predict a peak in the metallic regime in both n -type and intrinsic materials. (iii) In intrinsic materials, the Bir-Aronov-Pikus mechanism is found to be negligible compared with the D’yakonov-Perel’ mechanism. We also predict a peak in the temperature dependence of spin relaxation time which is due to the nonmonotonic temperature dependence of the electron-electron Coulomb scattering in intrinsic materials with small initial spin polarization. (iv) In p -type III-V semiconductors, the Bir-Aronov-Pikus mechanism dominates spin relaxation in the low-temperature regime only when the photoexcitation density is low. When the photoexcitation density is high, the Bir-Aronov-Pikus mechanism can be comparable with the D’yakonov-Perel’ mechanism only in the moderate

  12. Comparison of learning ability and memory retention in altricial (Bengalese finch, Lonchura striata var. domestica) and precocial (blue-breasted quail, Coturnix chinensis) birds using a color discrimination task.

    Science.gov (United States)

    Ueno, Aki; Suzuki, Kaoru

    2014-02-01

    The present study sought to assess the potential application of avian models with different developmental modes to studies on cognition and neuroscience. Six altricial Bengalese finches (Lonchura striata var. domestica), and eight precocial blue-breasted quails (Coturnix chinensis) were presented with color discrimination tasks to compare their respective faculties for learning and memory retention within the context of the two developmental modes. Tasks consisted of presenting birds with discriminative cues in the form of colored feeder lids, and birds were considered to have learned a task when 80% of their attempts at selecting the correctly colored lid in two consecutive blocks of 10 trials were successful. All of the finches successfully performed the required experimental tasks, whereas only half of the quails were able to execute the same tasks. In the learning test, finches required significantly fewer trials than quails to learn the task (finches: 13.5 ± 9.14 trials, quails: 45.8 ± 4.35 trials, P learning curve). In the memory retention tests, which were conducted 45 days after the learning test, finches retained the ability to discriminate between colors correctly (95.0 ± 4.47%), whereas quails did not retain any memory of the experimental procedure and so could not be tested. These results suggested that altricial and precocial birds both possess the faculty for learning and retaining discrimination-type tasks, but that altricial birds perform better than precocial birds in both faculties. The present findings imply that developmental mode is an important consideration for assessing the suitability of bird species for particular experiments. © 2013 Japanese Society of Animal Science.

  13. Hybrid Bloch brane

    Energy Technology Data Exchange (ETDEWEB)

    Bazeia, D.; Lima, Elisama E.M.; Losano, L. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, PB (Brazil)

    2017-02-15

    This work reports on models described by two real scalar fields coupled with gravity in the five-dimensional spacetime, with a warped geometry involving one infinite extra dimension. Through a mechanism that smoothly changes a thick brane into a hybrid brane, one investigates the appearance of hybrid branes hosting internal structure, characterized by the splitting on the energy density and the volcano potential, induced by the parameter which controls interactions between the two scalar fields. In particular, we investigate distinct symmetric and asymmetric hybrid brane scenarios. (orig.)

  14. BIOLOGICAL CHARACTERISTICS OF PRUSSIAN CARP (CARASSIUS AURATUS GIBELIO (BLOCH, 1782 COMMERCIAL STOCK OF THE DNIEPER-BUG ESTUARY

    Directory of Open Access Journals (Sweden)

    К. Heina

    2017-09-01

    Full Text Available Purpose. To provide the biological assessment of the silver Prussian carp (Carassius auratus gibelio (Bloch, 1782 commercial stock of the Dnieper-Bug estuary in the conditions of the transformed Dnieper river flow. Methodology. During the analysis of the biological state of the Prussian carp commercial stock, the main attention was given to the dynamics of age and sexual structure, length-weight growth rate, absolute fecundity and condition factor. The basic data were collected during the work of control-observation stations of the Institute of Fisheries in the Dnieper-Bug estuary during the current century. The collection and processing of ichthyological materials were performed in accordance with the generally accepted methodologies. Findings. The analysis showed that during the current century, the age structure of the Prussian carp of the Dnieper-Bug estuary was the most labile among other commercial cyprinids. It was found that as a result of an increase in the right wing of the age series, there was a gradual increase of the mean weighted age of its commercial stock. At the beginning of studies (2001-2002, the core of the stock was formed by age-3-6 fish (up ; however in subsequent years, a displacement of dominant groups toward the dominance of age-4-7 fish (more than 80% of the total stock was observed. At the same time, the relative number of age-3 fish (recruits was at a relatively high level – up to 10.6%. The linear growth varied more intensively until the age-5, but it reduced with ageing and did not show high variability. The body weight most variable was in age-4 fish (Cv=9.62%. The noted insignificant deviations in the body weight growth rate of the right wing of the age series was due to stable predominance of females in the stock structure, which were characterized by a variability of the mean weight as a result of different development of gonads. The dynamics of the age-related changes in the condition factor indicated on a

  15. La conciencia de la libertad (La filosofía moral como filosofía de la historia en Ernst Bloch

    Directory of Open Access Journals (Sweden)

    Gimbernat, José Antonio

    1991-10-01

    Full Text Available Not available.

    A partir del concepto hegeliano de «progreso en la conciencia de la libertad », se puede hacer una lectura de la filosofía moral de Bloch como filosofía de la historia. Ello conduce a una reino reinterpretación libre y materialista de Hegel y a una recuperación de la moral en el marxismo. En diálogo con Kant se hace posible descubrir el potencial utópico del énfasis subjetivo de la moral. El objetivo del reino de la libertad marxiano es la clave de una historización política de la libertad, heredada en parte de la tradición liberal, lo que exige a su vez una nueva definición del concepto de progreso.

  16. Anachronism in the writing of History: ¿Error or Possibility? Some reflections about the concept of time in Carlo Ginzburg, Marc Bloch and Georges Didi-Huberman

    Directory of Open Access Journals (Sweden)

    Maria Eugenia Chaves Maldonado

    2016-01-01

    Full Text Available In his unfinished and posthumously published book Apologie pour l’histoire, Marc Bloch bestowed on future historians a seminal legacy of critical reflections on the concept of time as the object of historical analysis. During the last decades, the concept of time in History has experienced a renewed interest by professional historians, in particular in reference to the category of anachronism. The Italian historian Carlo Ginzburg and the French art historian Georges Didi-Huberman are among those engaged in this debate. This article offers a reading of two works by these historians with the purpose of underlying the fundamental influence that Marc Bloch’s ideas on time had in Ginzburg and Didi-Hubermans’ critical interventions.

  17. Fenthion induced toxicity and histopathological changes in gill ...

    African Journals Online (AJOL)

    Tersoo

    2015-06-23

    Jun 23, 2015 ... to the herbicide, glyphosate. Afr. J. Biotechnol. 5:2480-2487. Pandey S, Kumar R, Sharma S, Napure NS, Srivastava SK, Verma MS. (2005). Acute toxicity bioassays of mercuric chloride and malathion on air-breathing fish Channa punctatus (Bloch). Ecotoxicol. Environ. Saf. 61:114-120. Peter JV, Cherian ...

  18. 3-D micromagnetic simulation of a Bloch line between C-sections of a 180 deg. domain wall in a left brace 1 0 0 right brace iron film

    CERN Document Server

    Huo, S; Tucker, J W; Rainforth, W M; Davies, H A

    2000-01-01

    The micromagnetic structure and energy of a Bloch line (BL) in an asymmetric 180 deg. Bloch domain wall in a 60 nm left brace 1 0 0 right brace iron film have been calculated. In the wall cross-sections on either side of the BL, the flux of magnetisation transverse to that of the domains was 'C' shaped, roughly normal to the plane of the film in its interior but bending nearly parallel to the surfaces as they are approached. The sense of this transverse flux is reversed at the BL. The energy of this BL was calculated to be considerably lower than the energies reported earlier for BLs in walls having 'S' shaped transverse flux cross-sections.

  19. Characterization of anomalous relaxation using the time-fractional Bloch equation and multiple echo T2*-weighted magnetic resonance imaging at 7 T.

    Science.gov (United States)

    Qin, Shanlin; Liu, Fawang; Turner, Ian W; Yu, Qiang; Yang, Qianqian; Vegh, Viktor

    2017-04-01

    To study the utility of fractional calculus in modeling gradient-recalled echo MRI signal decay in the normal human brain. We solved analytically the extended time-fractional Bloch equations resulting in five model parameters, namely, the amplitude, relaxation rate, order of the time-fractional derivative, frequency shift, and constant offset. Voxel-level temporal fitting of the MRI signal was performed using the classical monoexponential model, a previously developed anomalous relaxation model, and using our extended time-fractional relaxation model. Nine brain regions segmented from multiple echo gradient-recalled echo 7 Tesla MRI data acquired from five participants were then used to investigate the characteristics of the extended time-fractional model parameters. We found that the extended time-fractional model is able to fit the experimental data with smaller mean squared error than the classical monoexponential relaxation model and the anomalous relaxation model, which do not account for frequency shift. We were able to fit multiple echo time MRI data with high accuracy using the developed model. Parameters of the model likely capture information on microstructural and susceptibility-induced changes in the human brain. Magn Reson Med 77:1485-1494, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  20. A study in the computation time required for the inclusion of strain field effects in Bloch-wave simulations of TEM diffraction contrast images

    Energy Technology Data Exchange (ETDEWEB)

    Dulong, B.J. [Department of Physics, Acadia University, Wolfville, N.S., B4P 2R6 (Canada); Haynes, R.D. [Department of Mathematics and Statistics, Acadia University, Wolfville, N.S., B4P 2R6 (Canada); Robertson, M.D. [Department of Physics, Acadia University, Wolfville, N.S., B4P 2R6 (Canada)], E-mail: michael.robertson@acadiau.ca

    2008-04-15

    As transmission electron microscopy (TEM) imaging techniques continue to become more quantitative, interpretation of the experimental images demands that accurate image simulations be computed incorporating all important aspects of the image including: compositional, crystallographic and microscope effects, as well as contrast due to strain fields arising from stresses created by lattice misfit or defects. Incorporation of the effects of strain fields in the simulation of diffraction-contrast TEM images in the Bloch-wave formalism requires the integration of a system of first-order differential equations in order to modify the excitation amplitudes and produce contrast in the image. This integration is computationally demanding with the time for integration scaling as the cube of the number of beams included in the calculation. In order to investigate the computational requirements of the integration, a variety of numerical integration packages were evaluated with respect to timing and accuracy in the simulation of quantum dot, spherical inclusion and screw dislocation images. It was determined that a class of Adams-multistep methods can provide a decrease in computation time ranging from 2 to 4 as compared to the standard Runge-Kutta 4(5) approach depending on the simulation conditions.

  1. A study in the computation time required for the inclusion of strain field effects in Bloch-wave simulations of TEM diffraction contrast images.

    Science.gov (United States)

    Dulong, B J; Haynes, R D; Robertson, M D

    2008-04-01

    As transmission electron microscopy (TEM) imaging techniques continue to become more quantitative, interpretation of the experimental images demands that accurate image simulations be computed incorporating all important aspects of the image including: compositional, crystallographic and microscope effects, as well as contrast due to strain fields arising from stresses created by lattice misfit or defects. Incorporation of the effects of strain fields in the simulation of diffraction-contrast TEM images in the Bloch-wave formalism requires the integration of a system of first-order differential equations in order to modify the excitation amplitudes and produce contrast in the image. This integration is computationally demanding with the time for integration scaling as the cube of the number of beams included in the calculation. In order to investigate the computational requirements of the integration, a variety of numerical integration packages were evaluated with respect to timing and accuracy in the simulation of quantum dot, spherical inclusion and screw dislocation images. It was determined that a class of Adams-multistep methods can provide a decrease in computation time ranging from 2 to 4 as compared to the standard Runge-Kutta 4(5) approach depending on the simulation conditions.

  2. Comparative histological and histochemical studies on the pancreas of Labeo rohita (Hamilton, 1822, Mystus vittatus (Bloch, 1790 and Notopterus notopterus (Pallas, 1769

    Directory of Open Access Journals (Sweden)

    Padmanabha Chakrabarti

    2015-01-01

    Full Text Available The histological analysis, disposition and histochemical localization of tryptophan were investigated in the pancreas to compare the cellular organization and histochemical characterization in the pancreas of Labeo rohita (Hamilton, 1822, Mystus vittatus (Bloch, 1790 and Notopterus notopterus (Pallas, 1769 having different feeding habits. Histological analysis demonstrated that the exocrine pancreatic tissues were dispersed within the hepatic parenchyma and spleen in L. rohita. Thin septa of connective tissue separated parenchyma of liver and also the spleen from exocrine pancreatic cells. However, in M. vittatus, the discrete pancreatic tissue formed distinct oval or elongated acini interspersed with small area of islet of Langerhans and blood vessels. In N. notopterus, the rhomboidal acinar cells of discrete pancreatic tissue intercalated with comparatively clear and large islet of Langerhans. The exocrine acinar cells in all the three species were provided with prominent nuclei and densely packed zymogen granules. Histochemical localization revealed that the zymogen granules of exocrine acinar cells of all species exhibited varied intensities of tryptophan reaction, the precursor of various pancreatic enzymes which may be related to the food and feeding habits of the fishes under study.

  3. A new genus of proteocephalid tapeworm (Cestoda) from the marbled swamp eel Synbranchus marmoratus Bloch (Synbranchiformes: Synbranchidae) in the River Paraná basin, Argentina.

    Science.gov (United States)

    Arredondo, Nathalia J; Alves, Philippe Vieira; Gil de Pertierra, Alicia A

    2017-05-05

    Synbranchiella gen. n. is proposed to accommodate Synbranchiella mabelae sp. n. (Proteocephalidae: Monticelliinae) from the intestine of the marbled swamp eel Synbranchus marmoratus Bloch, in the River Colastiné, a tributary of the middle River Paraná in Argentina. The new genus is placed in the Monticelliinae because of the cortical position of the genital organs. It differs from all known monticelliine genera by the following combination of characters: (i) scolex robust, with a conical apex, without metascolex; (ii) biloculate suckers with a conspicuous septum separating unequally-sized loculi and a robust non-adherent area, lacking free posterior margin; (iii) vitelline follicles in two narrow lateral bands, extended throughout the nearly entire proglottid length; (iv) vagina always anterior to the cirrus-sac, with an inconspicuous vaginal sphincter; (v) a genital pore pre-equatorial. Scanning electron microscopy revealed three types of microtriches on the tegument surface: acicular and capiliform filitriches and gladiate spinitriches. A phylogenetic analysis of the large subunit nuclear ribosomal RNA gene (lsrDNA, D1-D3 domains) confirms that S. mabelae represents an independent lineage within a large clade comprised mainly from Neotropical taxa parasitising catfishes. This is the second proteocephalidean cestode described from a Neotropical synbranchiform fish host.

  4. Darboux transformation and soliton solutions for the generalized coupled variable-coefficient nonlinear Schrödinger-Maxwell-Bloch system with symbolic computation

    Science.gov (United States)

    Guo, Rui; Tian, Bo; Lü, Xing; Zhang, Hai-Qiang; Liu, Wen-Jun

    2012-04-01

    In an inhomogeneous nonlinear light guide doped with two-level resonant atoms, the generalized coupled variable-coefficient nonlinear Schrödinger-Maxwell-Bloch system can be used to describe the propagation of optical solitons. In this paper, the Lax pair and conservation laws of that model are derived via symbolic computation. Furthermore, based on the Lax pair obtained, the Darboux transformation is constructed and soliton solutions are presented. Figures are plotted to reveal the following dynamic features of the solitons: (1) Periodic mutual attractions and repulsions of four types of bound solitons: of two one-peak bright solitons; of two one-peak dark solitons; of two two-peak bright solitons and of two two-peak dark solitons; (2) Two types of elastic interactions of solitons: of two bright solitons and of two dark solitons; (3) Two types of parallel propagations of parabolic solitons: of two bright solitons and of two dark solitons. Those results might be useful in the study of optical solitons in some inhomogeneous nonlinear light guides.

  5. Impact of Salinity on the Incubation Rate and the Performance during the Nursery Phase of Square Head Climbing Perch (Anabas testudineus Bloch, 1792

    Directory of Open Access Journals (Sweden)

    Le, DV.

    2016-01-01

    Full Text Available Square head climbing perch (Anabas testudineus Bloch, 1792 is a high quality fish without small bones. It grows in a wide range of temperatures (10-42 oC, pH (3.5-9.5 and salinity (up to 16%. As regards climate change, this species may become important for aquaculture in the Tam Giang-Cau Hai lagoon near Hue city. To optimise the quality of fingerlings, we analyzed the effect of salinity levels on hatching and nursing in three subsequent experiments. Fertilization, hatching, survival and growth rates for 30 days were determined at salinity levels 0%, 5%, 7%, 13% and 15%. Water temperature and pH varied between 22-29.5 oC and 7.3-7.8, respectively. Between 0-5%, fertilization ratio was 77% to 83% and highest at 5%, but this dropped to 0% when salinity increased; hatching ratio was larger than 90%, but decreased to 0% at 13-15%. Between 0-11%, hatching time of fertilized eggs was not affected by salinity levels. The ratio of deformation gradually increased above 5%. After hatching at either 0 or 5%, survival ratios for square head climbing perch were above 13% up to 5%, but dropped to 0% at 9%. The growth after 30 days of nursing was higher at 5 and 7% compared with that of 0 and 3%.

  6. RESEARCHES REGARDING THE CHANGES OF SOME PHYSIOLOGICAL PARAMETERS AT THE PRUSSIAN CARP (Carassius auratus gibelio Bloch 1782 UNDER THE ACTION OF THE DUAL GOLD 960 EC HERBICIDE

    Directory of Open Access Journals (Sweden)

    Elena Diana Biţu

    2016-12-01

    Full Text Available Herbicides are chemical substances with selective toxic action (limited for some vegetal species or general (for any species, used to fight against weeds in the crops, fruit and grapes-growing fields, parks etc. The administration of herbicides though has complex effects on the biocenosis. In the aquatic environment, they have proved to be toxic not only for the aimed plants, but also for numerous species of animals. The deterioration of the aquatic environment is accentuated by the fact that plants that had died due to the treatment decompose themselves in a rapid manner, leading to the decrease of the oxygen level in the water, the final consequence being the increase in the death rate of the animals. This paper has studied the action of the Dual Gold 960 EC herbicide in different concentrations on some physiological indicators for the Prussian carp (Carassiusauratusgibelio Bloch 1782. The herbicide has had an inhibitive effect on the researched parameters for all the used concentrations.

  7. Response to the ration levels on growth, body composition, energy, and protein maintenance requirement of the Indian catfish (Heteropneustes fossilis-Bloch 1974).

    Science.gov (United States)

    Ahmed, Imtiaz

    2010-12-01

    An 8-week growth study was conducted to determine the effect of ration level, energy, and protein maintenance requirement of catfish, Heteropneustes fossilis-Bloch, fingerling (7.90±0.55 cm; 3.10±0.28 g) by feeding casein-gelatin-based purified diet (40% CP; 3.61 kcal g-1 GE) at six ration levels 1-6% of BW/day, at 0800 and 1700 h, in triplicate, with 20 fish per trough fitted with water flow-through system of volume 55 L. Maximum live weight gain, best feed conversion ratio (FCR), best specific growth rate (SGR), and highest protein efficiency ratio (PER) were evident for ration levels of 4-5% body weight. However, second-degree polynomial regression analysis for weight gain, FCR, PER, protein, and energy retention data indicated that the break-points occurred at 5.08, 4.18, 4.05, 4.16, and 4.17% BW/day, respectively. Significantly (P0.05) low at higher rations. Protein and energy retention values also produced significant (Pfeeding in the range of 4 to 4.5% BW/day, corresponding to 1.60-1.80 g protein and 14.46-16.27 kcal energy g100 g(-1) of the diet/day is optimum for the growth and efficient feed utilization of H. fossilis, while 2-3% ration levels (0.80-1.20 g protein and 7.23-10.84 kcal energy) suggest that these amounts approximate to the maintenance requirement of this fish.

  8. PATHOMORPHOLOGICAL AND CYTOMETRIC PARAMETERS OF BLOOD RED CELLS OF AGE-2 PRUSSIAN CARP (CARASSIUS AURATUS GIBELIO (BLOCH, 1782 IN THE CONDITIONS OF INTOXICATION WITH COPPER IONS

    Directory of Open Access Journals (Sweden)

    T. Sharamok

    2017-09-01

    Full Text Available Purpose. To detect the effect of elevated copper ion concentrations (10 aquaculture Maximum Permissible Limits on morphological and cytometric parameters of erythrocytes of age-2 Prussian carp (Carassius gibelio Bloch, 1782 in experimental and natural conditions. Methodology. During the work, summarized results of studies performed in 2015-2016 were used. Morphological and cytometric parameters of Prussian carp erythrocytes were determined in the conditions of natural habitats (Zaporizhzhia reservoir and an experiment. Copper ion concentration both in the experiment and natural conditions was similar and was 0.01 mg/L (10 aquaculture Maximum Permissible Limits. Experimental studies were performed during 21 days. In the control aquarium, fish were kept in the settled tap water; while in the experimental aquaria, intoxication of fish with copper ions was modelled by introducing CuSO4 in water. Blood smears were examined under 40x and 100 x magnifications with the use of microphotography (digital camera Sciencelab T500 5.17 M. Findings. The performed hematological studies showed that under the conditions of experimental chronic intoxication with copper ions (0.01 mg/L, age-2 Prussian carp had an increase in the share of immature forms of erythrocytes, increase in the number of erythrocytes with pathological signs (cell wall destruction, atypical forms, increase in the nucleus-cytoplasm ration, but the difference in cytometric parameters of erythrocytes between experimental and control fish was not significant. When comparing the morphometric parameters of erythrocytes of fish kept in experimental and natural conditions with similar copper ion concentrations (0.01 mg/L, a significant increase in the nucleus areas of mature erythrocytes was detected and, correspondingly, an increase in the nucleus-cytoplasm ratio of erythrocytes (by almost 30% in fish in experimental conditions compared to fish, which lived in the Zaporizhzhia reservoir. An increase

  9. The taxonomic status of Japanese threadfin bream Nemipterus japonicus (Bloch, 1791) (Perciformes: Nemipteridae) with a redescription of this species from the south china sea based on morphology and DNA barcodes

    Science.gov (United States)

    Ning, Ping; Sha, Zhongli; Hebert, Paul D. N.; Russell, Barry

    2015-02-01

    Because of its importance as a food source, Nemipterus japonicus (Bloch, 1791) (Nemipteridae) or Japanese threadfin bream is the best studied of these taxa, and numerous investigations have examined its fisheries, its biology and biochemistry. Despite such intensive work, the taxonomic status of N. japonicus has never been seriously questioned and it is regarded as a common species, widely distributed throughout the Indo-Western Pacific Ocean. In fact, Bloch's description of the type specimen of N. japonicus has ambiguous collection data and lacks a designation for the type locality, though it is probably Java. In this paper, DNA barcode results based on COI gene support the existence of two geographically separated lineages of the Japanese threadfin bream, both being an Indian Ocean and western Pacific lineage, with 2.7% sequence divergence, and the results indicate a possible existing of some cryptic species. The two lineages also possess a diagnostic difference in their belly color, with specimens in the South China Sea having a silver belly, while those from the Indian Ocean isolate specimen have a yellow coloration. Based upon new collections from the South China Sea, this species from the western Pacific is morphologically redescribed and its details of DNA barcode diversity are shown for the future investigations.

  10. Diploposthe laevis (Bloch Jacobi (Eucestoda, Hymenolepididae from Netta peposaca (Vieillot (Aves: Anatidae: first record for the Neotropical Region and a new host Diploposthe laevis (Bloch Jacobi (Eucestoda: Hymenolepididae em Netta peposaca (Vieillot (Aves, Anatidae: primeiro registro para Região Neotropical e novo hospedeiro

    Directory of Open Access Journals (Sweden)

    Eliane F. da Silveira

    2008-03-01

    Full Text Available One hundred eight rosy-billed pochards, Netta peposaca (Vieillot, 1816, collected in Brazil and Argentina were examined for endoparasites. Collection sites included the municipalities of Santa Vitória do Palmar and Jaguarão, Rio Grande do Sul State, Brazil (wintering site and Alvear, Corrientes Province, northern Argentina (nesting site. Birds were frozen in dry ice after collection. During necropsy they were categorized according to sex and maturation, either adult or juvenile. The cestode Diploposthe laevis (Bloch Jacobi, 1896 was found (prevalence 68.5%, mean infection was 2. The mean prevalence of D. laevis in Alvear (25.9% was higher than found in Jaguarão and Santa Vitória do Palmar, Rio Grande do Sul (19%, and could be related to the nesting site and to the period when the birds may ingest a higher amount of food. This is the first record of a species of the genus Diploposthe in anatideans from South America, and the first record of the species in N. peposaca. Details of the cirrus pouch and vagina were described based on histological sections.Com o objetivo de conhecer a helmintofauna do marrecão, Netta peposaca (Vieillot, 1816, na América do Sul, 108 aves foram amostradas. Os pontos de captura foram os municípios de Santa Vitória do Palmar e Jaguarão, no Estado do Rio Grande do Sul, sul do Brasil (pólo de invernia, e em Alvear, Província de Corrientes, região norte da Argentina (pólo de nidificação, entre 2002 e 2004. As aves foram congeladas em gelo seco logo após o abate. Durante o procedimento de necropsia tiveram o sexo identificado, e foram classificadas de acordo com estado de maturação sexual, em juvenil e adulto. O cestóide Diploposthe laevis (Bloch Jacobi, 1896 foi encontrado com prevalência média de 68,5% e intensidade média de infecção de dois espécimes por hospedeiro. A prevalência média de D. laevis em Alvear (25,9% foi maior do que a encontrada em Jaguarão e Santa Vitória do Palmar, Rio Grande

  11. mRNA’S SECONDARY STRUCTURE FOR HAPLOTYPES OF THE GENE WHICH DETERMINS THE CYTOCHROME’S B SYNTHESIS, FOR CARASSIUS AURATUS GIBELIO BLOCH. 1783 INDIVIDUALS SAMPLED FROM MOVILENI AND IASI POPULATIONS

    Directory of Open Access Journals (Sweden)

    Lucian Gorgan

    2007-08-01

    Full Text Available : In present paper, the main purpose was to establish the mRNA’s secondary structure for the gene which determines the cytochrome’s b synthesis, for Carassius auratus gibelio Bloch. 1783 individuals, having the origin in two different populations - Movileni and Iaşi, as well as those structures’s comparison, with similar models of the same gene, taken from the GenBank, for different species and subspecies of Carassius genera. Thus, regions from mtDNA were sequenced for 10 individuals of each analyzed population, based on a purified DNA matrix, using a method with phenol : chloroform : izoamyl alcohol (25:24:1. Those genes were subsequently amplified and sequenced using two complementary universal primers, obtaining both complementary chains, which ulterior formed a unique strand.MRNA’s secondary structure transcription and modeling was made using the GeneQuest module of LaserGene’s program.

  12. Ecologie des poissons capitaines: Polydactylus quadrifilis (Cuvier, 1829, Galeoides decadactylus (Bloch, 1795 et Pentanemus quinquarius (Linné, 1758 de la pêcherie artisanale maritime de Grand-Lahou (Côte d'Ivoire

    Directory of Open Access Journals (Sweden)

    Konan Kouassi, S.

    2013-01-01

    Full Text Available The Ecology of Polynemids: Poydactylus quadrifilis (Cuvier, 1829, Galeoides decadactylus (Bloch, 1795 and Pentanemus quinquarius (Linné, 1758 of the Artisanal Marine Fisheries of Grand Lahou (Ivory Coast. The ecology of Polynemids (Poydactylus quadrifilis, Galeoides decadactylus and Pentanemus quinquarius has been studied starting from the unloads of the artisanal marine fisheries of Grand Lahou (Ivory Coast. The temperature of the littoral is high during June and May with an average of 27,55±0,8 °C such as between November and December (29,30±0,1 °C. It is low between July and September (24,5±1,5 °C. On the other hand, salinity has its higher average values (35±0,8 g/l during the cold periods (July at September and lowest during the hot period, from October to January (33,9±0,3 g/l. The physiological needs of Polynemids cause seasonal migrations of the juveniles and adults. Hence the crossing of the estuary of the lagoon during the cold period, from June to August by the juveniles of Polydactylus quadrifilis and Galeoides decadactylus. For Polydactylus quadrifilis the annual recruitment of young specimens is identical to that of the adults, which is contrary to that of Galeoides decadactylus and Pentanemus quinquarius.

  13. Isolation of microsatellite markers for Bletilla striata and cross ...

    African Journals Online (AJOL)

    esiri

    Biotechology, Guiyang 550002, China. 2State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences,. Guiyang 550002, China. 3State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences,. Beijing 100093, China.

  14. T1-refBlochi: high resolution 3D post-contrast T1 myocardial mapping based on a single 3D late gadolinium enhancement volume, Bloch equations, and a reference T1.

    Science.gov (United States)

    Hu, Chenxi; Sinusas, Albert J; Huber, Steffen; Thorn, Stephanie; Stacy, Mitchel R; Mojibian, Hamid; Peters, Dana C

    2017-08-18

    High resolution 3D T1 mapping is important for assessment of diffuse myocardial fibrosis in left atrium or other thin-walled structures. In this work, we investigated a fast single-TI 3D high resolution T1 mapping method that directly transforms a 3D late gadolinium enhancement (LGE) volume to a 3D T1 map. The proposed method, T1-refBlochi, is based on Bloch equation modeling of the LGE signal, a single-point calibration, and assumptions that proton density and T2* are relatively uniform in the heart. Several sources of error of this method were analyzed mathematically and with simulations. Imaging was performed in phantoms, eight swine and five patients, comparing T1-refBlochi to a standard spin-echo T1 mapping, 3D multi-TI T1 mapping, and 2D ShMOLLI, respectively. The method has a good accuracy and adequate precision, even considering various sources of error. In phantoms, over a range of protocols, heart-rates and T1 s, the bias ±1SD was -3 ms ± 9 ms. The porcine studies showed excellent agreement between T1-refBlochi and the multi-TI method (bias ±1SD = -6 ± 22 ms). The proton density and T2* weightings yielded ratios for scar/blood of 0.94 ± 0.01 and for myocardium/blood of 1.03 ± 0.02 in the eight swine, confirming that sufficient uniformity of proton density and T2* weightings exists among heterogeneous tissues of the heart. In the patients, the mean T1 bias ±1SD in myocardium and blood between T1-refBlochi and ShMOLLI was -9 ms ± 21 ms. T1-refBlochi provides a fast single-TI high resolution 3D T1 map of the heart with good accuracy and adequate precision.

  15. Zymosan-induced immune challenge modifies the stress response of hypoxic air-breathing fish (Anabas testudineus Bloch): Evidence for reversed patterns of cortisol and thyroid hormone interaction, differential ion transporter functions and non-specific immune response.

    Science.gov (United States)

    Simi, S; Peter, Valsa S; Peter, M C Subhash

    2017-09-15

    Fishes have evolved physiological mechanisms to exhibit stress response, where hormonal signals interact with an array of ion transporters and regulate homeostasis. As major ion transport regulators in fish, cortisol and thyroid hormones have been shown to interact and fine-tune the stress response. Likewise, in fishes many interactions have been identified between stress and immune components, but the physiological basis of such interaction has not yet delineated particularly in air-breathing fish. We, therefore, investigated the responses of thyroid hormones and cortisol, ion transporter functions and non-specific immune response of an obligate air-breathing fish Anabas testudineus Bloch to zymosan treatment or hypoxia stress or both, to understand how immune challenge modifies the pattern of stress response in this fish. Induction of experimental peritonitis in these fish by zymosan treatment (200ngg(-1)) for 24h produced rise in respiratory burst and lysozomal activities in head kidney phagocytes. In contrast, hypoxia stress for 30min in immune-challenged fish reversed these non-specific responses of head kidney phagocytes. The decline in plasma cortisol in zymosan-treated fish and its further suppression by hypoxia stress indicate that immune challenge suppresses the cortisol-driven stress response of this fish. Likewise, the decline in plasma T3 and T4 after zymosan-treatment and the rise in plasma T4 after hypoxia stress in immune-challenged fish indicate a critical role for thyroid hormone in immune-stress response due to its differential sensitivity to both immune and stress challenges. Further, analysis of the activity pattern of ion-dependent ATPases viz. Na(+)/K(+)-ATPase, H(+)/K(+)-ATPase and Na(+)/NH4(+)-ATPase indicates a functional interaction of ion transport system with the immune response as evident in its differential and spatial modifications after hypoxia stress in immune-challenged fish. The immune-challenge that produced differential pattern

  16. Eğirdir Gölü'nde Gümüşi Havuz Balığı, Carassius gibelio (Bloch, 1782 Avcılığında Kullanılan Monofilament Fanyalı Ağların Seçiciliği

    Directory of Open Access Journals (Sweden)

    Bayram KORKMAZ

    2014-09-01

    Full Text Available In this study, it has been investigated that the characteristics of the selectivity of monofilament trammel nets having 50, 55, 60 mm bar length. This study was carried out on prussian carp Carassius gibelio (Bloch,1782 caught in Lake Eğirdir. An indirect method developed by Holt (1963 was used for determining the selectivity parameters. Common selection factor as SF=4.753 and common standard deviation as SD=2.347 were calculated for monofilament trammel nets. Common selection factor used of the optimum catch lengths of prussian carp in 50, 55 and 60 mm bar length were 23.77; 26.14 and 28.52 cm respectively. The optimum catch lengths were compared with lenghts at first maturity of prussian carp in Lake Eğirdir. Trammel nets of this study do not cause the overfishing on the prussian carp stock

  17. Rȇve er action : Bloch, Heidegger et Levinas (Dream and Action. Bloch, Heidegger and Levinas

    Directory of Open Access Journals (Sweden)

    Jan Bierhanzl

    2016-06-01

    Full Text Available In this paper, I seek to rehabilitate the category of possibility and possibility’s conversion into action that Ernst Bloch’s concept of ‘concrete utopia’ represents, in particular as he elaborated this concept in the first and third volumes of his masterpiece, The Principle of Hope. What’s at issue here in concrete terms is the articulation of wishing or of will in the form of utopian subjectivity, and the conversion of wishing and will into choice and action. One may wish many things, the choices are many, but only one of them may be wanted. How then can the indecision that is inherent to wishing be linked to an idea of decision making and acting that is not at odds with future-oriented wishing? We shall start here with a Heideggerian critique of ‘pure wishful thinking’ and draw on Bloch’s reading of this notion in an attempt to defend future-oriented wishing as expressed in utopian thought and reconcile it with a philosophy of action.

  18. Iktiofauna Sungai Sangkir Kabupaten Rokan Hulu Provinsi Riau (Ichthyofauna of Sangkir River, Rokan Hulu District Riau Province

    Directory of Open Access Journals (Sweden)

    Nunuk Dian Pranata

    2016-12-01

    Full Text Available This study was conducted in Sangkir river branch of Rokan Kiri river Sangkir village, Rokan Hulu district, Riau Province from May of July 2016. The aim of this study was to inventory the fish species in Sangkir river branch of Rokan Kiri River with direct observation (survey. Five sampling locations were determined purposely based on the environmental condition that could be represented by the river condition. A total of 288 individuals of fish belonging to 3 orders, 7 families, 13 genera and 16 species were recorded in this study, namely Barbodes balleroides, Barbodes gonionotus, Barbichthys leavis, Channa striata, Cyclocheilichthys apogon, Labiobarbus fasciatus, Mystus nigriceps, Ompok eugeneiatus, Osteochilus hasseltii, Osteochilus mycrocephalus, Pangio semicincta, Pristolepis grooti, Thynnichthys polylepis, Trichogaster leerii, Trichogaster trichopterus and Trichopsis vittata. Cyprinidae was the most abundance fish in this study. Penelitian ini telah dilaksanakan di sungai Sangkir, anak sungai Rokan Kiri, desa Sangkir, Kabupaten Rokan Hulu, Provinsi Riau pada bulan Mei sampai Juli 2016. Penelitian ini bertujuan untuk mengetahui jenis-jenis ikan di sungai Sangkir anak Sungai Rokan Kiri dengan metode pengamatan langsung (survei dengan penetapan stasiun pengambilan sampel secara purposive sampling. Penetapan stasiun berdasarkan kondisi lingkungan yang terdiri dari 5 stasiun penelitian. Hasil penelitian  didapatkan sebanyak 288 individu ikan yang terdiri dari 3 ordo, 7 famili 13 genus dan 16 spesies. Spesies yang didapatkan yaitu Barbodes balleroides, Barbodes gonionotus, Barbichthys leavis, Channa striata, Cyclocheilichthys apogon, Labiobarbus fasciatus, Mystus nigriceps, Ompok eugeneiatus, Osteochilus hasseltii, Osteochilus mycrocephalus, Pangio semicincta, Pristolepis grooti, Thynnichthys polylepis Trichogaster leerii, Trichogaster trichopterus dan Trichopsis vittata. Cyprinidae merupakan kelompok ikan yang paling banyak dalam penelitian ini.

  19. Perceptual chunking in the self-produced songs of Bengalese finches (Lonchura striata var. domestica).

    Science.gov (United States)

    Suge, Rie; Okanoya, Kazuo

    2010-05-01

    Like humans, songbirds, including Bengalese finches, have hierarchical structures in their vocalizations. When humans perceive a sentence, processing occurs in phrase units, not words. In this study, we investigated whether songbirds also perceive their songs by chunks (clusters of song notes) rather than single song notes. We trained male Bengalese finches to react to a short noise in a Go/NoGo task. We then superimposed the noise onto recordings of their own songs and examined whether the reaction time was affected by the location of the short noise, that is, whether the noise was placed between chunks or in the middle of a chunk. The subjects' reaction times to the noise in the middle of a chunk were significantly longer than those to the noise placed between chunks. This result was not observed, however, when the songs were played in reverse. We thus concluded that Bengalese finches perceive their songs by chunks rather than single notes.

  20. Composition operators between Bloch type spaces and Zygmund ...

    Indian Academy of Sciences (India)

    1Hubei Province Key Laboratory of Intelligent Robot, School of Science, Wuhan. Institute of Technology, Wuhan 430073, China. 2Wuhan Institute of Physics and Mathematics, The Chinese Academy of Science,. Wuhan 430071, China. E-mail: daijineng@163.com; ouyang@wipm.ac.cn. MS received 1 September 2009; ...

  1. Optical Control of Plasmonic Bloch Modes on Periodic Nanostructures

    NARCIS (Netherlands)

    Gjonaj, B.; Aulbach, Jochen; Johnson, P.M.; Mosk, Allard; Kuipers, L.; Lagendijk, Aart

    2012-01-01

    We study and actively control the coherent properties of surface plasmon polaritons (SPPs) optically excited on a nanohole array. Amplitude and phase of the optical excitation are externally controlled via a digital spatial light modulator (SLM) and SPP interference fringe patterns are designed and

  2. ( ucleus rofeno (Bloch s assay ofos to ) using y

    African Journals Online (AJOL)

    SAM

    et al., 2011a). Fishes are considered as sensitive organism in toxicity studies and can play a significant role in assessing potential risks associated with contamination in aquatic environment by environmental contaminants. Fishes can respond to mutagens at low concentrations of toxicants in a manner similar to higher ...

  3. Equivalent moduli of continuity, Bloch's theorem for pluriharmonic ...

    Indian Academy of Sciences (India)

    where C is a positive constant which depends only on f (see [13]). Dyakonov [8] characterized the holomorphic functions in ω in terms of their modulus. Later in Theorems A and B of [22], Pavlovic came up with a relatively simple proof of the results of Dyakonov. Recently, many authors considered this topic and generalized.

  4. Generalization of the Bloch-Messiah-Zumino theorem

    Science.gov (United States)

    Dobaczewski, J.

    2000-07-01

    It is shown how to construct a basis in which two arbitrary complex antisymmetric matrices C and C' acquire simultaneously canonical forms. The present construction is not restricted by any conditions on the properties of the C+C' matrix. Canonical bases pertaining to the generator-coordinate-method treatment of many-fermion systems are discussed.

  5. Biochemical composition of the alligator pipefish, Syngnathoides biaculeatus (Bloch, 1785)

    Science.gov (United States)

    Sanaye, Sushant Vilas; Pawar, Ashwini Pandurang; Rivonker, Chandrasheker Umanath; Sreepada, Rayadurga Anantha; Ansari, Zakir Ali; Ram, Anirudh

    2017-11-01

    Considering the economic importance in traditional Chinese medicine (TCM) and lack of baseline information, we evaluated the proximate composition, fatty acid and amino acid profiles, trace element content and C:N ratio in the alligator pipefish, Syngnathoides biaculeatus. Amongst proximate principals, a crude protein formed the major biochemical component ((58.9±2.2)% dry weight). Mean percent concentrations (dry weight) of other components such as a total lipid (TL), ash and nitrogen-free extract measured were, (1.8±0.2)%, (19.2±2.2)% and (20.1±0.45)%, respectively. The fatty acid profile revealed the presence of 27 saturated fatty acids (SFA) with 13 straight-chained and 14 branched-chained, 28 unsaturated fatty acids (UFA) with 14 monounsaturated and 14 polyunsaturated and nine other minor fatty acids. Mean percent contributions of total SFAs and UFAs to TL were found to be (55.41±0.24)% and (44.05±0.25)%, respectively. Altogether, 16 different amino acids with an equal number of essential (EAA) and non-essential (NAA) ones were identified. Percent contributions by EAA and NAA to the total amino acid content were 38.11% and 61.89%, respectively. Trace metal concentrations in S. biaculeatus were generally low and their distribution followed the order, Mg>Fe>Zn>Mn>Cu>Cr>Ni>Hg>Co. The C:N ratio was (4.37±0.04)%. The profile of major biochemical constituents in alligator pipefish, S. biaculeatus revealed its potential use in TCM as well as a nutritional diet for human consumption. The results of the study would also form the basis for formulation and optimization of diets for the culture of S. biaculeatus.

  6. Bloch Electron in a Magnetic Field and the Ising Model

    Science.gov (United States)

    Krasovsky, I. V.

    2000-12-01

    The spectral determinant det\\(H-ɛI\\) of the Azbel-Hofstadter Hamiltonian H is related to Onsager's partition function of the 2D Ising model for any value of magnetic flux Φ = 2πP/Q through an elementary cell, where P and Q are coprime integers. The band edges of H correspond to the critical temperature of the Ising model; the spectral determinant at these (and other points defined in a certain similar way) is independent of P. A connection of the mean of Lyapunov exponents to the asymptotic (large Q) bandwidth is indicated.

  7. Clipboard: Etroplus suratensis (Bloch), the State Fish of Kerala

    Indian Academy of Sciences (India)

    Permanent link: http://www.ias.ac.in/article/fulltext/jbsc/037/06/0925-0931. Keywords. Etroplus suratensis; breeding; raceway; enclosure farming; sanctuary. Author Affiliations. K G Padmakumar1 L Bindu1 P S Manu1. Kerala Agricultural University, Regional Agricultural Research Station, Kumarakom, Kerala 686 566, India ...

  8. On history and salvation in Emmanuel Levinas and Ernst Bloch

    African Journals Online (AJOL)

    p1243322

    introduces a future which is novel and that cannot be captured in, or reduced to, an all-encompassing synthesis. ... each other in time, and each instant has a novel quality, such that discontinuity is allowed for within ... remain a subject in which every adventure would revert into the adventure of a fate”.22. Let us now look in ...

  9. Equivalent moduli of continuity, Bloch's theorem for pluriharmonic ...

    Indian Academy of Sciences (India)

    Department of Mathematics, Hunan Normal University, Changsha, Hunan 410081, People's Republic of China; Department of Mathematics and Computational Science, Hengyang Normal University, Hengyang, Hunan 421008, People's Republic of China; Department of Mathematics, Indian Institute of Technology Madras, ...

  10. ( ucleus rofeno (Bloch s assay ofos to ) using y

    African Journals Online (AJOL)

    SAM

    EC50) with product name CELCRON (manufactured by EXCEL. Crop Care Ltd. ... a sim valid this indire. MN i. 2003 genot pollut riment period e fish speci mentioned t ol groups at analysis in ol and expos ficant in the f the highest M at 96 h (3.65.

  11. Biochemical composition of the alligator pipefish, Syngnathoides biaculeatus (Bloch, 1785)

    Science.gov (United States)

    Sanaye, Sushant Vilas; Pawar, Ashwini Pandurang; Rivonker, Chandrasheker Umanath; Sreepada, Rayadurga Anantha; Ansari, Zakir Ali; Ram, Anirudh

    2016-12-01

    Considering the economic importance in traditional Chinese medicine (TCM) and lack of baseline information, we evaluated the proximate composition, fatty acid and amino acid profiles, trace element content and C:N ratio in the alligator pipefish, Syngnathoides biaculeatus. Amongst proximate principals, a crude protein formed the major biochemical component ((58.9±2.2)% dry weight). Mean percent concentrations (dry weight) of other components such as a total lipid (TL), ash and nitrogen-free extract measured were, (1.8±0.2)%, (19.2±2.2)% and (20.1±0.45)%, respectively. The fatty acid profile revealed the presence of 27 saturated fatty acids (SFA) with 13 straight-chained and 14 branched-chained, 28 unsaturated fatty acids (UFA) with 14 monounsaturated and 14 polyunsaturated and nine other minor fatty acids. Mean percent contributions of total SFAs and UFAs to TL were found to be (55.41±0.24)% and (44.05±0.25)%, respectively. Altogether, 16 different amino acids with an equal number of essential (EAA) and non-essential (NAA) ones were identified. Percent contributions by EAA and NAA to the total amino acid content were 38.11% and 61.89%, respectively. Trace metal concentrations in S. biaculeatus were generally low and their distribution followed the order, Mg>Fe>Zn>Mn>Cu>Cr>Ni>Hg>Co. The C:N ratio was (4.37±0.04)%. The profile of major biochemical constituents in alligator pipefish, S. biaculeatus revealed its potential use in TCM as well as a nutritional diet for human consumption. The results of the study would also form the basis for formulation and optimization of diets for the culture of S. biaculeatus.

  12. Crystal Structure and Raman studies of dsFP483, a Cyan Fluorescent Protein from Discosoma striata

    Science.gov (United States)

    Malo, Gabrielle D.; Wang, Meitian; Wu, Di; Stelling, Allison L.; Tonge, Peter J.; Wachter, Rebekka M.

    2008-01-01

    To better understand the diverse mechanisms of spectral tuning operational in fluorescent proteins, we have determined the 2.1 Å X-ray structure of dsFP483 from the reef-building coral Discosoma. This protein is a member of the cyan color class of Anthozoa fluorescent proteins, and exhibits broad, double-humped excitation and absorbance bands, with a maximum at 437–400 nm and a shoulder at 453 nm. Although these features support a heterogeneous ground state for the protein-intrinsic chromophore, peak fluorescence occurs at 483 nm for all excitation wavelengths, suggesting a common emissive state. Optical properties are insensitive to changes in pH over the entire range of protein stablility. The refined crystal structure of the biological tetramer (spacegroup C2) demonstrates that all protomers bear a cis-coplanar chromophore chemically identical to that in green fluorescent protein (avGFP). To test the roles of specific residues in color modulation, the optical properties of the H163Q and K70M variants were investigated. Although absorbance bands remain broad, peak excitation maxima are red-shifted to 455 and 460 nm, emitting cyan and green light respectively. To probe chromophore ground state features, Raman spectra were collected using 752 nm excitation. Surprisingly, the positions of key Raman bands of wild-type dsFP483 are most similar to those of the neutral avGFP chromophore, whereas the K70M spectra are more closely aligned with the anionic form. The Raman data provide further evidence of a mixed ground state with chromophore populations that are modulated by mutation. Possible internal protonation equilibria, structural heterogeneity in the binding sites, and excited state proton transfer mechanisms are discussed. Structural alignments of dsFP483 with the homologs DsRed, amFP486, and zFP538-K66M suggest that natural selection for cyan color is an exquisitely fine-tuned and highly cooperative process involving a network of electrostatic interactions that may vary substantially in composition and arrangement. PMID:18395223

  13. Nucleic acids digestion by enzymes in the stomach of snakehead (Channa argus) and banded grouper (Epinephelus awoara).

    Science.gov (United States)

    Liu, Yu; Zhang, Yanfang; Jiang, Wei; Wang, Jing; Pan, Xiaoming; Wu, Wei; Cao, Minjie; Dong, Ping; Liang, Xingguo

    2017-02-01

    Dietary nucleic acids (NAs) were important nutrients. However, the digestion of NAs in stomach has not been studied. In this study, the digestion of NAs by enzymes from fish stomach was investigated. The snakehead pepsins (SP) which were the main enzymes in stomach were extracted and purified. The purity of SP was evaluated by SDS-PAGE and HPLC. The snakehead pepsin 2 (SP2) which was the main component in the extracts was used for investigating the protein and NAs digestion activity. SP2 could digest NAs, including λ DNA and salmon sperm DNA. Interestingly, the digestion could be inhibited by treatment of alkaline solution at pH 8.0 and pepstatin A, and the digestion could happen either in the presence or absence of hemoglobin (Hb) and BSA as the protein substrates. Similarly, the stomach enzymes of banded grouper also showed the NAs digestion activity. NAs could be digested by the stomach enzymes of snakehead and banded grouper. It may be helpful for understanding both animal nutrition and NAs metabolic pathway.

  14. THE DISTRIBUTION AND BIODIVERSITY OF FISHES IN LEBAK PAMPANGAN SWAMP SOUTH SUMATRA PROVINCE

    Directory of Open Access Journals (Sweden)

    Dina Muthmainah

    2013-12-01

    Full Text Available This research was conducted to evaluate the fish distribution and biodiversity within three types of swamp ecosystem with different water sources in Pampangan Sub-district during July to December 2011. The field observation were conducted in three different types of swamp. Ecological data and samples were collected from three sampling points in each swamp type. Parameters including local distribution, diversity index, similarity index, evenness and species richness, were analyzed. The results show a number of 9,723 fishes corresponding to 46 species were collected, the fish categorized into 16 families belonging to five orders. Eight species were found in all type of swamps i.e. Mystus nemurus, Channa striata, Cyclocheilchthys apogon, Cyclocheilichthys armatus, Pristolepis fasciata, Puntius lineatus, Osteochillus hasselti, and Trichogaster pectoralis. A diversity index of fishes in Pampangan Swamp ranged from 2.31 to 2.85, indicating moderate values. The evenness index was high more than 50%. The highest similarity was found between type 1 and type 3 of (0.43. The highest diversity index (2.85 found in type 2 of swamp indicates the swamp in more stable condition.

  15. A reappraisal of the evolution of Asian snakehead fishes (Pisces, Channidae) using molecular data from multiple genes and fossil calibration.

    Science.gov (United States)

    Adamson, Eleanor A S; Hurwood, David A; Mather, Peter B

    2010-08-01

    Freshwater snakehead fishes (Channidae) provide an interesting target for phylogenetic analysis for the following reasons, their unusual biology, potential for cryptic diversity and availability of a good fossil record. Here, a multi-locus molecular phylogeny was constructed and calibrated using two fossil dates to estimate divergence times within the family. Sampling aimed to explore interspecific divergence of Channa species across Southeast Asia and intra-specific variation where species possessed natural geographical ranges that were extensive. Results contradict divergence times estimated previously independently from single locus mitochondrial data or the fossil record and suggest that after divergence from African taxa 40-50 Ma, evolution of Asian snakeheads has been heavily influenced by multiple broad scale dispersal events across India and Southeast Asia. A similar pattern of divergence within multiple clades suggests that west-east dispersal was limited for many taxa during the Miocene. Deep intra-specific divergence was inferred for C. striata, indicating that long historical periods of isolation ( approximately 8Ma) have not resulted in the evolution of reproductive isolation within this species. Results support suggestions that C. marulia like fishes in northern Cambodia may constitute an undescribed species, and that Indian C. diplogramma warrants taxonomic recognition as being distinct from Southeast Asian C. micropeltes, with the two taxa last sharing a common ancestor in the mid- to late-Miocene. Copyright 2010 Elsevier Inc. All rights reserved.

  16. Feeding biology of the hottentot, Pachymetopon blochH (Val.), with ...

    African Journals Online (AJOL)

    1987-10-13

    Oct 13, 1987 ... trends were marked. A progressive change in diet occurs with fish size, larger individuals consuming progressively more algae. The hottentot diet differs from those of a number of co-occuring sparids in being far more generalized. Hottentot feed throughout the diel cycle, although feeding activity is markedly ...

  17. Stratégies de reproduction du poisson-chat Synodontis schall (Bloch ...

    African Journals Online (AJOL)

    La reproduction du poisson-chat Synodontis schall a été étudiée en milieux lacustre et fluviatile, respectivement dans les rivières Bia et Agnébi. Le caractère permanent de l\\'eau, dans le lac a favorisé une plus grande période de reproduction de l\\'espèce dans la retenue, contrairement aux zones fluviatiles sujettes à des ...

  18. Dental treatment considerations for a pediatric patient with incontinentia pigmenti (Bloch-Sulzberger syndrome)

    Science.gov (United States)

    Chen, Amy Yi-Ling; Chen, Kevin

    2017-01-01

    Incontinentia pigmenti (IP) is a uncommon gene disorder, heritage with X-linked dominant mode. IP patients have a characteristic dentition varying from marked hypodontia to delayed eruption and conical crowns on both dentitions. A 5½-year-old girl, whose mother and younger sister were also diagnosed with IP, has the whirling-like pigmented skin lesion over her trunk and four extremities. Four primary teeth and multiple permanent tooth germs were found to be congenital missing. Dental considerations of further treatment were discussed with her parents including the preservation of primary molars, possible interim prosthesis in mixed or permanent dentition, full mouth rehabilitation with orthodontic and prosthodontic combined treatment, and implant therapy in adulthood. Early and longitudinal involvement of pediatric dentist to deal with the dental complications of IP can not only solve the esthetic problem and oral function but also maintain the oral health of children with IP to adulthood. PMID:28729805

  19. Near-field imaging of light propagation in photonic crystal waveguides: Explicit role of Bloch harmonics

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.; Volkov, V.S.; Søndergaard, Thomas

    2002-01-01

    We employ a collection scanning near-field optical microscope (SNOM) to image the propagation of light at telecommunication wavelengths along straight and bent regions of silicon-on-insulator photonic crystal waveguides (PCWs) formed by removing a single row of holes in the triangular 410-nm...

  20. Enhanced Spontaneous Emission of Bloch Oscillation Radiation from a Single Energy Band

    Science.gov (United States)

    2006-06-30

    Schomburg, S. Brandl, O. Kus, K. F. Renk , M. C. Wanke, S. J. Allen, A. A. Ignatov, V. Ustinov, A. Zhukov, and P. S. Kop’ev, Appl. Phys. Lett. 77, 1259 (2000...J. Grenzer, S. Brandl, I. Lingott, A. A. Ignatov, K. F. Renk , D. G. Pavel’ev, Yu. Koschurinov, B. Ya. Melzer, V. M. Ustinov, S. V. Ivanov, A. Zhukov...Rodwell, Phys. Rev. Lett. 76, 2973 1996. 9 S. Vinnerl, E. Schomburg, S. Brandl, O. Kus, K. F. Renk , M. C. Wanke, S. J. Allen, A. A. Ignatov, V

  1. Classification of "Quaternionic" Bloch-Bundles. Topological Quantum Systems of Type AII

    Science.gov (United States)

    De Nittis, Giuseppe; Gomi, Kiyonori

    2015-10-01

    We provide a classification of type AII topological quantum systems in dimension d = 1, 2, 3, 4. Our analysis is based on the construction of a topological invariant, the FKMM-invariant, which completely classifies "Quaternionic" vector bundles ( a.k.a. "symplectic" vector bundles) in dimension . This invariant takes value in a proper equivariant cohomology theory and, in the case of examples of physical interest, it reproduces the familiar Fu-Kane-Mele index. In the case d = 4 the classification requires a combined use of the FKMM-invariant and the second Chern class. Among the other things, we prove that the FKMM-invariant is a bona fide characteristic class for the category of "Quaternionic" vector bundles in the sense that it can be realized as the pullback of a universal topological invariant.

  2. Kuhu kadus antropoloogia? : ehk vajadus "inimloomuse" järele / Maurice Bloch ; tlk. Maarja Kaaristo

    Index Scriptorium Estoniae

    Bloch, Maurice

    2007-01-01

    Antropoloogia kui distsipliini akadeemilisest ajaloost, sotsiaal- ja kultuuriantropoloogia hariduse puudujääkidest. Antropoloogia põhilistest uurimisteemadest ja uurimisteooriatest: difusionismist, evolutsionismist ning funktsionalismist

  3. Electronic states in crystals of finite size quantum confinement of bloch waves

    CERN Document Server

    Ren, Shang Yuan

    2017-01-01

    This book presents an analytical theory of the electronic states in ideal low dimensional systems and finite crystals based on a differential equation theory approach. It provides precise and fundamental understandings on the electronic states in ideal low-dimensional systems and finite crystals, and offers new insights into some of the basic problems in low-dimensional systems, such as the surface states and quantum confinement effects, etc., some of which are quite different from what is traditionally believed in the solid state physics community. Many previous predictions have been confirmed in subsequent investigations by other authors on various relevant problems. In this new edition, the theory is further extended to one-dimensional photonic crystals and phononic crystals, and a general theoretical formalism for investigating the existence and properties of surface states/modes in semi-infinite one-dimensional crystals is developed. In addition, there are various revisions and improvements, including us...

  4. Optimization of artificial fertilization in the stinging catfish Heteropneustes fossilis (Bloch).

    Science.gov (United States)

    Christopher, J Godwin; Murugesan, A G; Sukumaran, N

    2011-02-01

    Determination of optimum sperm requirement in artificial breeding helps to improve the fertilization efficiency, sperm economy and minimize the sacrificing of males for milt. Quantification of sperm cells was done by spectrophotometer at 420 nm followed by haemocytometer counting. Best correlation (r2 = 0.97) was recorded. The minimum number of sperm required for optimal fertilization success in Heteropneustes fossilis was determined. An average fertilization success of 78-93% was recorded at 8 × 103 to 8 × 107 sperm per egg. The optimum contact duration of gametes was 5 minutes. The highest fertilization rate of 98.18% was recorded at 8 × 107 spermatozoa.egg-1.

  5. Bloch-Wave Engineered Submicron Diameter Micropillars with Quality Factors Exceeding 10,000

    DEFF Research Database (Denmark)

    Hofling, S.; Lermer, M.; Gregersen, Niels

    2011-01-01

    Adiabatic design submicron diameter quantum-dot micropillars have been designed and implemented for cavity quantum electrodynamics experiments. Ultra-high experimental quality factors (>10,000) are obtained for submicron diameters and strong light-matter interaction is observed.......Adiabatic design submicron diameter quantum-dot micropillars have been designed and implemented for cavity quantum electrodynamics experiments. Ultra-high experimental quality factors (>10,000) are obtained for submicron diameters and strong light-matter interaction is observed....

  6. Reducing disorder-induced losses for slow light photonic crystal waveguides through Bloch mode engineering

    DEFF Research Database (Denmark)

    Mann, Nishan; Combrié, Sylvian; Colman, Pierre

    2013-01-01

    We present theory and measurements ofdisorder-induced losses for low loss 1.5 mmlong slow light photonic crystal waveguides. A recent class of dispersion engineered waveguides increases the bandwidth of slow light and shows lower propagation losses for the same group index. Our theory and experim...

  7. Controlled Population of Floquet-Bloch States via Coupling to Bose and Fermi Baths

    Directory of Open Access Journals (Sweden)

    Karthik I. Seetharam

    2015-12-01

    Full Text Available External driving is emerging as a promising tool for exploring new phases in quantum systems. The intrinsically nonequilibrium states that result, however, are challenging to describe and control. We study the steady states of a periodically driven one-dimensional electronic system, including the effects of radiative recombination, electron-phonon interactions, and the coupling to an external fermionic reservoir. Using a kinetic equation for the populations of the Floquet eigenstates, we show that the steady-state distribution can be controlled using the momentum and energy relaxation pathways provided by the coupling to phonon and Fermi reservoirs. In order to utilize the latter, we propose to couple the system and reservoir via an energy filter which suppresses photon-assisted tunneling. Importantly, coupling to these reservoirs yields a steady state resembling a band insulator in the Floquet basis. The system exhibits incompressible behavior, while hosting a small density of excitations. We discuss transport signatures and describe the regimes where insulating behavior is obtained. Our results give promise for realizing Floquet topological insulators.

  8. Complete mitochondrial genome of freshwater shark Wallago attu (Bloch & Schneider) from Indus River Sindh, Pakistan.

    Science.gov (United States)

    Laghari, Muhammad Younis; Lashari, Punhal; Xu, Peng; Zhao, Zixia; Jiang, Li; Narejo, Naeem Tariq; Xin, Baoping; Sun, Xiaowen; Zhang, Yan

    2016-01-01

    Complete mitochondrial genome of fresh water giant catfish, Wallago attu, was isolated by LA PCR (TakaRa LAtaq, Dalian, China); and sequenced by Sanger's method to obtain the complete mitochondrial genome. The complete mitogenome was 15,639 bp in length and contains 13 typical vertebrate protein-coding genes, 2 rRNA and 22 tRNA genes. The whole genome base composition was estimated to be 31.17% A, 28.15% C, 15.55% G and 25.12% T. The complete mitochondrial genome of catfish, W. attu, provides the fundamental tools for genetic breeding.

  9. Effect of three diets in the experimental culture of the common snook (Centropomus undecimalis Bloch, 1792

    Directory of Open Access Journals (Sweden)

    Carmen Polonía R

    2017-09-01

    Full Text Available Objective. To evaluate the effect of three diets on the growth of juvenile common snook (Centropomus undecimalis maintained in freshwater ponds Materials and methods. 108 juvenile of common snook were homogenous and randomly distributed in a pond, divided into 9 corrals of 50 m2. Three diets were applied (D1: commercial food for trout, 45% protein; D2: commercial food for cobia, 50% protein and D3: fresh fish, 17.52% protein. The experimental treatments were assigned in triplicate and diets were supplied in two daily doses. Biometrics were performed every 20 days to assess: weight, size, Length-Weight correlation, Feed Conversion Factor (FCA, Condition Factor (K, Specific Growth Rate (SGR and survival; during 120 days. The results were evaluated with a one-way ANOVA, when differences (p<0.05 were found the means were compared by test Median Mood, otherwise a pos-hoc test was performed (Tukey HSD. Results. Applying the test of Mood Median significant differences were found, showing the highest growth with D2, where values of SGR=0.65±0.09 g/day; FCA=3.76 and K=0.81±0.06. Survival was D1=51.4%, D2=50% and D3=77.8% without inferring statistically among the different diets. Conclusions. The culture of this species in freshwater ponds with commercial food for cobia, is viable in terms of growth and weight gain.

  10. Web-based description of the space radiation environment using the Bethe-Bloch model

    CERN Document Server

    Cazzola, Emanuele; Lapenta, Giovanni

    2015-01-01

    Space weather is a rapidly growing area not only in scientific and engineering applications but also in physics education and in the interest of the public. We focus especially on space radiation and its impact on space exploration. The topic is highly interdisciplinary bringing together fundamental concepts of nuclear physics with aspects of radiation protection and space science. We present a new approach to presenting the topic by developing a web-based tool that combines some of the fundamental concepts from these two fields in a single tool that can be developed in the context of advanced secondary or undergraduate university education. We present DREADCode, an outreach or teaching tool to asses rapidly the current conditions of the radiation field in space. DREADCode uses the available data feeds from a number of ongoing space missions to produce a first order approximation of the dose an astronaut would receive during a mission of exploration in deep space. DREADcode is based on a intuitive GUI interfa...

  11. Phylogeography and RAPD-PCR variation in Hoplias malabaricus (Bloch, 1794 (Pisces, Teleostei in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Dergam Jorge A.

    2002-01-01

    Full Text Available In the Rio Doce basin of southeastern Brazil, the freshwater fish Hoplias malabaricus (trahira is a widespread predatory characin and one of the few resilient native fishes in a highly impacted lake system. In order to test for genetic differentiation in populations within this basin and for biogeographic relationships among populations of this species in other basins, a study was conducted using RAPD-PCR analysis of Rio Doce samples (N = 63 and phylogeographic analyses with mitochondrial DNA (mtDNA haplotypes, including the Rio Grande and Macacu river basins. In the Rio Doce basin, the patterns of genetic similarity of RAPD-PCR markers (individual fingerprinting and Nei?s genetic distance suggest the existence of two genetically different groups, one composed of the lacustrine populations Carioca and Dom Helvécio, and the other of riverine and the remaining lacustrine populations. The differences in the RAPD-PCR patterns may be explained by the existence of sub-basins within this lacustrine system. A maximum parsimony tree of cytochrome b fragment (383 base pairs supports the view that trahiras of the Rio Doce share a complex biogeographic history with those of neighboring basins. The phylogeographic patterns may be explained by a common history of the watersheds of the Rio Doce, Paraíba do Sul, and Rio Grande basins, corroborating the hypothesis of a Plio-Pleistocene separation of these drainage systems, forming the Mantiqueira "divortium aquarium".

  12. Mechanical Properties of Laminate Materials: From Surface Waves to Bloch Oscillations

    DEFF Research Database (Denmark)

    Liang, Z.; Willatzen, Morten; Christensen, Johan

    2015-01-01

    We propose hitherto unexplored and fully analytical insights into laminate elastic materials in a true condensed-matter-physics spirit. Pure mechanical surface waves that decay as evanescent waves from the interface are discussed, and we demonstrate how these designer Scholte waves are controlled...... by the geometry as opposed to the material alone. The linear surface wave dispersion is modulated by the crystal filling fraction such that the degree of confinement can be engineered without relying on narrow-band resonances but on effective stiffness moduli. In the same context, we provide a theoretical recipe......, and we demonstrate this numerically for structures with millimeter and centimeter dimensions in the kilohertz to megahertz range. Analytical predictions agree entirely with full wave simulations showing how elastodynamics can mimic quantum-mechanical condensed-matter phenomena....

  13. A teratologia múltipla: Robert Bloch e o seu bestiário

    Directory of Open Access Journals (Sweden)

    Alcebíades Diniz Miguel

    2008-10-01

    Full Text Available Howard Phillips Lovecraft acreditava que os povos, para criarem obras fantásticas de terror sobrenatural, deveriam ter certa “inclinação” para o deslumbramento diante do irracional, afirmando que a França e seu povo, por exemplo, seriam racionais demais para tanto. O escritor cita os judeus no rol dos povos possuidores de uma mitologia, com seus golems, dybbuks e outras criaturas, capaz de inspirar o terror sobrenatural.

  14. Discontinuous Galerkin Approximations for Computing Electromagnetic Bloch Modes in Photonic Crystals

    NARCIS (Netherlands)

    Lu, Zhongjie; Cesmelioglu, A.; van der Vegt, Jacobus J.W.; Xu, Y.

    We analyze discontinuous Galerkin finite element discretizations of the Maxwell equations with periodic coefficients. These equations are used to model the behavior of light in photonic crystals, which are materials containing a spatially periodic variation of the refractive index commensurate with

  15. Histopathology biomarker responses in Asian sea bass, Lates calcarifer (Bloch exposed to copper

    Directory of Open Access Journals (Sweden)

    A. Maharajan

    2016-10-01

    Full Text Available Copper is a trace element necessary for the normal growth and metabolism of living organisms. If exceeds its limit it becomes pollutant and causes pathological effects. Asian sea bass (Lates calcarifer was exposed to sublethal concentrations of copper for 28 days and histopathological alterations were noticed in the gill, liver, muscle and intestine. Epithelial necrosis, hypertrophy, rupture of gill epithelium and haemorrhage at primary lamellae were observed after 7 days of exposure. Lifting of epithelium, oedema and fusion of adjacent secondary lamellae were conspicuous at 28 days of exposure. The experimental liver tissue showed reduction in the size of hepatocytes, vacuolisation, and hypertrophy. The intestine displayed fused microvilli, sloughing of mucus membrane and swollen cells. Muscle bundles with severe oedema and their thickening and separation were more pronounced in sublethal treatment of copper in the muscle. Several histopathological changes observed in various fish organs would serve a useful purpose in evaluating the toxic effects of copper. The present study clearly demonstrated that all the treated body organs exhibited significant damage with response; amongst the body organs the liver is an important target organ for copper toxicity in L. calcarifer and this species could be possibly used as a model organism for toxicity studies.

  16. Pisces, Ophidiiformes, Ophidiidae, Brotula barbata (Bloch & Schneider, 1801: First record off Ceará,northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Paiva, C. C.

    2010-01-01

    Full Text Available Brotula barbata is recorded for the first time from Ceará, northeastern Brazil. The species was previouslyknown in the western Atlantic from North Carolina to southeastern Brazil, but there are some gaps between these regions.A single specimen was collected from a traditional line fishing fleet operating in the Mucuripe Sea, Ceará, during August2007. We noticed a meristic difference between the specimen examined and the information from the literature. Howeverthis difference did not make the identification difficult. The new record of B. barbata fills geographic distribution gaps ofthis species in the western Atlantic.

  17. Caloric densities of ingested food of Etroplus suratensis (Bloch) grown in a culture pond

    Digital Repository Service at National Institute of Oceanography (India)

    Sumitra-Vijayaraghavan; Krishnakumari, L.; Dhawan, R.M.; Royan, J.P.

    Analyses of stomach contents of E.suratensis indicated that it is principally a phytoplankton-detritus feeder. Biochemical analyses of the ingested food showed that of the total consumed food, 44% was contributed by ash content, while 56...

  18. Evaluacion del contenido de aminoacidos en guabina , bloch 1794, capturadas en el embalse hipereutrofico de Suata

    National Research Council Canada - National Science Library

    Acuna, Julymar; Gonzalez, Ernesto Jose; de los Angeles Alvarez, Maria; Penaherrera, Carlos; Barrero, Marinela

    2011-01-01

    ... esenciales para humanos, tales como, lisina, metionina, cisteina, treonina y triptofano [23, 29, 32]. Los productos pesqueros son particularmente buena fuente de lisina, que se encuentra en muy bajas proporciones en los cereales, el producto alimenticio mas importante en el mundo. Una reduccion en el suministro de lisina en la dieta puede conducir a p...

  19. Effects of stocking density on growth and production performance of indigenous stinging catfish, Heteropneustes fossilis (Bloch

    Directory of Open Access Journals (Sweden)

    A.H.M. Kohinoor

    2012-12-01

    Full Text Available An on-farm experiment was undertaken in nine earthen ponds to evaluate the growth and production potentials of stinging catfish shing, Heteropneustes fossilis for the period of six months from March to August 2010. Three stocking densities such as 1,25,000 (T1, 1,87,500 (T2 and 2,50,000 ha-1 (T3 were tested with three replications each. Fish were fed with commercial pelleted feed containing 35% crude protein. After six months rearing, the mean harvesting weights of shing were 69.42±6.20, 58.74±3.85 and 49.50±4.52g in T1, T2 and T3, respectively. Significant (P<0.05 highest mean harvesting weight was found in T1. The best survival was found in T1 (87% among the treatments. The calculated mean production of shing (H. fossilis in three treatments such as T1, T2 and T3 were 7549±52, 9031±71 and 8786±60 kg ha-1, respectively, which were significantly different (p<0.05 from each other.

  20. Ontogeny of the digestive tract in butter catfish Ompok bimaculatus (Bloch) larvae.

    Science.gov (United States)

    Pradhan, P K; Jena, J K; Mitra, G; Sood, N; Gisbert, E

    2012-12-01

    The ontogeny of the digestive tract was studied histologically in butter catfish Ompok bimaculatus from hatching to 30 days post-hatching (dph). At hatching, the digestive tract of butter catfish consisted of a straight tube with a smooth lumen dorsally attached to the yolk sac. Between 1 and 2 dph, the mouth opened, oral valves were visible and canine-like teeth and taste buds were detected. During this period, intestine was differentiated into the anterior and posterior intestine, and the digestive accessory glands were also developed. Exogenous feeding started at 2 dph, and there was a 2-day mixed endogenous-exogenous feeding period. Most of the yolk sac reserves were consumed between 2 and 3 dph, and by 5 dph, the yolk sac was completely depleted and no longer visible in histological sections. Between 3 and 4 dph, several vacuoles (neutral lipids) were observed in the intestine and also in hepatocytes, indicating a functional absorption of nutrients from food. At 8 dph, differentiation of gastric glands was noticed, and by 9-11 dph, there were abundant gastric tubular glands arranged along numerous longitudinal folds. During the same period, pyloric sphincter appeared as an epithelial fold that separated the stomach from the anterior intestine. From 12 dph to the end of the study at 30 dph, no noticeable histological modifications were observed. The development of gastric glands is considered as the last major events in digestive tract development and their presence designates the end of larval period and the onset of the juvenile period. Hence, it is suggested that, butter catfish larvae have a morphologically complete digestive tract by 12 dph. These findings on the development of the digestive system in butter catfish may lead to a better understanding of the ontogeny and would be useful to improve the larval rearing techniques of this promising catfish species for freshwater aquaculture diversification.

  1. Near-field imaging of light propagation in photonic crystal waveguides: Explicit role of Bloch harmonics

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.; Volkov, V.S.; Søndergaard, Thomas

    2002-01-01

    We employ a collection scanning near-field optical microscope (SNOM) to image the propagation of light at telecommunication wavelengths along straight and bent regions of silicon-on-insulator photonic crystal waveguides (PCWs) formed by removing a single row of holes in the triangular 410-nm...... PCW bends, bend loss is evaluated and found to noticeably increase with the increase of the light wavelength from similar to1 dB at 1520 nm to similar to6 dB at 1570 nm. We analyze light intensity variations along PCWs measured with the SNOM at different distances from the sample surface. Considering...

  2. Cellular immune responses and phagocytic activity of fishes exposed to pollution of volcano mud.

    Science.gov (United States)

    Risjani, Yenny; Yunianta; Couteau, Jerome; Minier, Christophe

    2014-05-01

    Since May 29, 2006, a mud volcano in the Brantas Delta of the Sidoarjo district has emitted mud that has inundated nearby villages. Pollution in this area has been implicated in detrimental effects on fish health. In fishes, leukocyte and phagocytic cells play a vital role in body defenses. We report for the first time the effect of "LUSI" volcano mud on the immune systems of fish in the Brantas Delta. The aim of this study was to find biomarkers to allow the evaluation of the effects of volcanic mud and anthropogenic pollution on fish health in the Brantas Delta. The study took places at the Brantas Delta, which was polluted by volcano mud, and at reference sites in Karangkates and Pasuruan. Leukocyte numbers were determined using a Neubauer hemocytometer and a light microscope. Differential leukocyte counts were determined using blood smears stained with May Grunwald-Giemsa, providing neutrophil, lymphocyte and monocyte counts. Macrophages were taken from fish kidney, and their phagocytic activity was measured. In vitro analyses revealed that leukocyte and differential leukocyte counts (DLC) were higher in Channa striata and Chanos chanos caught from the polluted area. Macrophage numbers were higher in Oreochromis mossambicus than in the other species, indicating that this species is more sensitive to pollution. In areas close to volcanic mud eruption, all specimens had lower phagocytic activity. Our results show that immune cells were changed and phagocytic activity was reduced in the polluted area indicating cytotoxicity and alteration of the innate immune system in fishes exposed to LUSI volcano mud and anthropogenic pollution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Calibrating snakehead diversity with DNA barcodes: expanding taxonomic coverage to enable identification of potential and established invasive species.

    Science.gov (United States)

    Serrao, Natasha R; Steinke, Dirk; Hanner, Robert H

    2014-01-01

    Detecting and documenting the occurrence of invasive species outside their native range requires tools to support their identification. This can be challenging for taxa with diverse life stages and/or problematic or unresolved morphological taxonomies. DNA barcoding provides a potent method for identifying invasive species, as it allows for species identification at all life stages, including fragmentary remains. It also provides an efficient interim taxonomic framework for quantifying cryptic genetic diversity by parsing barcode sequences into discontinuous haplogroup clusters (typical of reproductively isolated species) and labelling them with unique alphanumeric identifiers. Snakehead fishes are a diverse group of opportunistic predators endemic to Asia and Africa that may potentially pose significant threats as aquatic invasive species. At least three snakehead species (Channa argus, C. maculata, and C. marulius) are thought to have entered North America through the aquarium and live-food fish markets, and have established populations, yet their origins remain unclear. The objectives of this study were to assemble a library of DNA barcode sequences derived from expert identified reference specimens in order to determine the identity and aid invasion pathway analysis of the non-indigenous species found in North America using DNA barcodes. Sequences were obtained from 121 tissue samples representing 25 species and combined with public records from GenBank for a total of 36 putative species, which then partitioned into 49 discrete haplogroups. Multiple divergent clusters were observed within C. gachua, C. marulius, C. punctata and C. striata suggesting the potential presence of cryptic species diversity within these lineages. Our findings demonstrate that DNA barcoding is a valuable tool for species identification in challenging and under-studied taxonomic groups such as snakeheads, and provides a useful framework for inferring invasion pathway analysis.

  4. Calibrating snakehead diversity with DNA barcodes: expanding taxonomic coverage to enable identification of potential and established invasive species.

    Directory of Open Access Journals (Sweden)

    Natasha R Serrao

    Full Text Available Detecting and documenting the occurrence of invasive species outside their native range requires tools to support their identification. This can be challenging for taxa with diverse life stages and/or problematic or unresolved morphological taxonomies. DNA barcoding provides a potent method for identifying invasive species, as it allows for species identification at all life stages, including fragmentary remains. It also provides an efficient interim taxonomic framework for quantifying cryptic genetic diversity by parsing barcode sequences into discontinuous haplogroup clusters (typical of reproductively isolated species and labelling them with unique alphanumeric identifiers. Snakehead fishes are a diverse group of opportunistic predators endemic to Asia and Africa that may potentially pose significant threats as aquatic invasive species. At least three snakehead species (Channa argus, C. maculata, and C. marulius are thought to have entered North America through the aquarium and live-food fish markets, and have established populations, yet their origins remain unclear. The objectives of this study were to assemble a library of DNA barcode sequences derived from expert identified reference specimens in order to determine the identity and aid invasion pathway analysis of the non-indigenous species found in North America using DNA barcodes. Sequences were obtained from 121 tissue samples representing 25 species and combined with public records from GenBank for a total of 36 putative species, which then partitioned into 49 discrete haplogroups. Multiple divergent clusters were observed within C. gachua, C. marulius, C. punctata and C. striata suggesting the potential presence of cryptic species diversity within these lineages. Our findings demonstrate that DNA barcoding is a valuable tool for species identification in challenging and under-studied taxonomic groups such as snakeheads, and provides a useful framework for inferring invasion pathway

  5. Monoclonal antibody to serum immunoglobulins of Clarias batrachus and its application in immunoassays.

    Science.gov (United States)

    Sood, Neeraj; Chaudhary, Dharmendra K; Singh, Akhilesh; Rathore, Gaurav

    2012-12-15

    Serum immunoglobulins of Clarias batrachus (Cb-Ig) were purified by affinity chromatography using bovine serum albumin as capture ligand. Under reducing conditions in SDS-PAGE, Cb-Ig was composed of a heavy (H) chain (68.7 kDa) and two light (L) chains (27.4 and 26.3 kDa). Purified Cb-Ig was used to produce a monoclonal antibody (MAb) designated E4 MAb that belonged to IgG1 subclass. In Western blotting, this MAb showed binding to H chain of purified Cb-Ig and putative H chains in reduced sera of C. batrachus, Clarias gariepinus and Heteropneustes fossilis. However, no binding was observed with serum protein of Labeo rohita and Channa striata. Cross-reactivity of anti-Cb-Ig MAb was observed with serum of C. batrachus, C. gariepinus and H. fossilis in competitive ELISA. In immunoblotting of non-reduced Cb-Ig with E4 MAb, four bands assumed to be tetrameric, trimeric, dimeric and monomeric form were observed. In flow cytometric analysis of the gated lymphocytes, the number of surface Ig-positive (Ig+) cells in blood, spleen, kidney and thymus of C. batrachus was determined to be 50.1 ± 3.1, 55.1 ± 3.36, 42.4 ± 4.81 and 5.1 ± 0.89%, respectively, using E4 MAb. Ig+ cells were also demonstrated in formalin-fixed paraffin embedded tissue sections of spleen, kidney, thymus and smears of blood mononuclear cells in indirect immunoperoxidase test. The developed MAb was employed to detect pathogen-specific immunoglobulins in the sera of C. batrachus immunized with killed Edwardsiella tarda, by an indirect ELISA. This monoclonal antibody can be useful tool in immunological research and assays. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Potensi Ikan Air Tawar Budidaya sebagai Bahan Baku Produk Nutraseutikal Berbasis Serum Albumin Ikan

    Directory of Open Access Journals (Sweden)

    Rini Susilowati

    2015-05-01

    Full Text Available Nutraseutikal berbasis Fish Serum Albumin (FSA adalah produk komersial yang berasal dari sumber perairan. Namun, oleh karena produk ini secara umum diproduksi dari ikan gabus (Channa striata di alam, pasokan bahan baku dapat menjadi masalah pada produksi yang berkesinambungan. Penelitian ini telah dilakukan dengan menganalisis kandungan FSA dari 17 ikan air tawar budidaya, untuk mendapatkan bahan baku alternatif bagi produk nutraseutikal berbasis FSA. 3–10 individu ikan air tawar (150–500 g dari jenis ordo Perciformes, Anguilliformes, Cypriniformes, Osteoglossiformes, dan Siluriformes telah diambil secara acak dari lokasi budidaya ikan di Bogor dan Cianjur (Jawa Barat. Ekstraksi protein larut air dilakukan menggunakan Ultra Turax homogeniser dengan pelarut akuabides. Analisis FSA telah dilakukan menggunakan High Performance Liquid Chromatography (HPLC. Hasil dari penelitian menunjukkan bahwa kadar FSA dari 17 ekstrak air dari ikan berada pada rentang 42,51 to 215,57 mg/g, dengan kadar FSAikan gabus pembanding adalah 107,28 ± 3,2 mg/g. Konsentrasi FSA tertinggi ditemukan sebesar 215,57 ± 52,84 mg/g dari ekstrak air ikan gurame (Osphronemus gouramy. Analisis lebih lanjut terhadap komposisi asam amino menggunakan Gas Chromatography – Flame Ionization Detector (GC-FID menemukan bahwa ekstrak air ikan gabus memiliki konsentrasi asam amino esensial dan non-esensial yang lebih tinggi dibandingkan dengan ikan gurame. Hal ini menunjukkan banyaknya protein lain selain FSA pada ekstrak air ikan gabus dibandingkan ikan gurame. Berdasarkan hasil ini, ekstrak air ikan gurame memiliki konsentrasi FSA yang lebih besar dan relatif lebih murni dibandingkan ekstrak air ikan gabus, sehingga merupakan alternatif yang prospektif sebagai bahan baku untuk produk nutraseutikal berbasis FSA.

  7. UJI ORGANOLEPTIK FORMULASI BISKUIT FUNGSIONAL BERBASIS TEPUNG IKAN GABUS (Ophiocephalus striatus (The Organoleptic Functional Biscuit Formulation Based on Snakehead Fish (Ophiocephalus striata Flour

    Directory of Open Access Journals (Sweden)

    Dewi Kartika Sari

    2014-07-01

    15% TI sebesar 73,33% dan rasa tertinggi pada 10% TI sebesar 58,33%. Penerimaan panelis menunjukkan bahwa perlakuan tepung ikan gabus berpengaruh nyata (p0,05 terhadap aroma, rasa, warna dan keseluruhan biskuit. Berdasarkan pertimbangan penerimaan panelis maka terpilih formula biskuit dengan substitusi 15% tepung ikan gabus. Kata kunci: Biskuit fungsional, subtitusi, fortifikasi

  8. Mitochondrial dysfunction, oxidative stress and apoptosis revealed by proteomic and transcriptomic analyses of the striata in two mouse models of Parkinson’s disease

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Mark H.; Qian, Weijun; Wang, Haixing; Petyuk, Vladislav A.; Bloom, Joshua S.; Sforza, Daniel M.; Lacan, Goran; Liu, Dahai; Khan, Arshad H.; Cantor, Rita M.; Bigelow, Diana J.; Melega, William P.; Camp, David G.; Smith, Richard D.; Smith, Desmond J.

    2008-02-10

    The molecular mechanisms underlying the changes in the nigrostriatal pathway in Parkinson disease (PD) are not completely understood. Here we use mass spectrometry and microarrays to study the proteomic and transcriptomic changes in the striatum of two mouse models of PD, induced by the distinct neurotoxins 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and methamphetamine (METH). Proteomic analyses resulted in the identification and relative quantification of 912 proteins with two or more unique peptides and 85 proteins with significant abundance changes following neurotoxin treatment. Similarly, microarray analyses revealed 181 genes with significant changes in mRNA following neurotoxin treatment. The combined protein and gene list provides a clearer picture of the potential mechanisms underlying neurodegeneration observed in PD. Functional analysis of this combined list revealed a number of significant categories, including mitochondrial dysfunction, oxidative stress response and apoptosis. Additionally, codon usage and miRNAs may play an important role in translational control in the striatum. These results constitute one of the largest datasets integrating protein and transcript changes for these neurotoxin models with many similar endpoint phenotypes but distinct mechanisms.

  9. Efeito dos conservantes sobre a densidade calórica em músculos de Hoplias aff. malabaricus (Bloch, 1794 (Osteichthyes, Erythrinidae Effect of preservatives on caloric density in the muscles of Hoplias aff. malabaricus (Bloch, 1794 (Osteichthyes, Erythrinidae

    Directory of Open Access Journals (Sweden)

    Milena Morimoto

    2002-05-01

    Full Text Available A conservação de amostras para a determinação dos valores calóricos em estudos de bioenergética de peixes tem se apresentado, na literatura, com uma variedade de métodos. Com o intuito de identificar o efeito de conservantes sobre os resultados obtidos com as diferentes técnicas de conservação, foram coletados exemplares adultos de Hoplias aff. malabaricus (Osteichthyes, Erythrinidae na planície de inundação do rio Paraná. De cada exemplar, foram retiradas 5 amostras da musculatura, as quais foram submetidas aos seguintes tratamentos: formol (4%, álcool (70%, congelamento (-10oC, nitrogênio líquido (-180oC e estufa à 60oC (amostra controle. Depois de 30 dias, todas as amostras foram secas em estufa à 60oC e posteriormente procedeu-se à determinação calórica de cada uma das amostras em bomba calorimétrica. Detectaram-se diferenças significativas entre os tratamentos (ANOVA: N=206; F=50,28; pThe preservation of samples for caloric values determination in bioenergetic studies of fish has been presented literature with a variety of methods. To identify the effect of preservatives over the results obtained with different preservation techniques, adult individuals of Hoplias aff. malabaricus (Osteichthyes, Erythrinidae were collected in Paraná river floodplain. From each fish, five samples were extracted from its dorsal muscle and submitted each sample for a different treatment: ice (-10ºC, formaldehyde (4%, alcohol (70%, liquid nitrogen (-180oC and a control sample immediately oven dried (60oC. After 30 days, the treatments were oven dried (60oC and caloric values of each sample were determined in a caloric bomb. Significant differences among the treatments were found (ANOVA: n = 206; F = 50.28; p < 0.001. Some evaluations of the effects of each treatment were presented for further comparisons with the results published in literature.

  10. Efeito dos conservantes sobre a densidade calórica em músculos de Hoplias aff. malabaricus (Bloch, 1794) (Osteichthyes, Erythrinidae) Effect of preservatives on caloric density in the muscles of Hoplias aff. malabaricus (Bloch, 1794) (Osteichthyes, Erythrinidae)

    National Research Council Canada - National Science Library

    Milena Morimoto; Evanilde Benedito-Cecilio

    2002-01-01

    ... bioenergética de peixes tem se apresentado, na literatura, com uma variedade de métodos. Com o intuito de identificar o efeito de conservantes sobre os resultados obtidos com as diferentes técnicas de...

  11. Poecilancistrium caryophyllum (Diesing, 1850 (Cestoda, Trypanorhyncha, parasito de Macrodon ancylodon (Bloch & Schneider, 1801 do litoral Norte do Brasil Poecilancistrium caryophyllum (Diesing, 1850 (Cestoda, Trypanorhyncha, parasite of Macrodon ancylodon (Bloch & Schneider, 1801 from the Northern littoral of Brazil

    Directory of Open Access Journals (Sweden)

    Silvio Abner Lameira de Oliveira

    2009-12-01

    Full Text Available O objetivo desta pesquisa foi registrar a presença de cestoides Trypanorhyncha, suas prevalências e intensidades de infecção, na musculatura e serosa abdominal parietal de 50 exemplares de Macrodon ancylodon, capturados no litoral Norte do Brasil e beneficiados em Belém, Estado do Pará, durante o período de junho de 2004 a janeiro de 2005. A musculatura e serosa abdominal dos peixes foram examinadas em mesa de inspeção candling table após o filetamento das amostras. Oito peixes encontravam-se parasitados por plerocercoides da espécie Poecilancistrium caryophyllum, com prevalência de 16% e intensidade média de infecção de um plerocerco por peixe, tendo como único sítio de infecção a musculatura. A espécie Poecilancistrium caryophyllum é, pela primeira vez, registrada para M. ancylodon.The aim of this research was to report the presence of Trypanorhyncha cestodes, their prevalence and mean intensity in the muscles musculature and abdominal serose in commercial fish processed in Belém, Pará State. Fifty specimens of M. ancylodon were captured in the North Coast of Brazil. The musculature and adjacent abdominal serose of fish were analized in a "candling table" after filleted. Eight specimens were parasitized by plerocercoids of Poecilancistrium caryophyllum, with a prevalence of 16% and mean intensity of infection of one plerocercus per fish, varying from the unique site of infection was the musculature. The species P. caryophyllum is reported by the first time on M. ancylodon.

  12. Florence Hulak. Sociétes et mentalités. La science historique de Marc Bloch.

    Directory of Open Access Journals (Sweden)

    Renán Silva

    2016-01-01

    Full Text Available Hay obras de análisis histórico (y esta lo es, aunque en el campo de la epistemología de la historia que pueden resumirse fácilmente, bien sea por su contenido renovador, bien sea por sus equívocos y errores, o bien sea por su propio carácter rutinario (una más entre una cadena de libros previsibles en su enfoque y en sus resultados. Hay otras obras que solicitan, de quien se ocupa de ellas y trata de presentarlas ante una comunidad de lectores alejada de su lugar de producción y de recepción iniciales del texto, tan solo un sobrevuelo inicial, una mención de sus temas y propósitos centrales, un énfasis repetido sobre su significado e importancia, para animar a los lectores a que se interesen en el debate planteado por el libro de referencia y, sobre todo, a que no se deje pasar de largo una oportunidad de discusión que puede servir para refinar el planteamiento de problemas de los que se habla de manera repetida con actitud poco reflexiva, repetitiva y rutinaria. Creo que este es el caso del libro reciente de Florence Hulak, Sociétés et mentalités que queremos presentar aquí, a través de una reseña centrada simplemente en sus grandes temas, dejando para otros momentos el debate preciso (textos en mano y con multiplicadas referencias, ejemplos, contra ejemplos y argumentaciones sobre puntos concretos de los planteamientos de la autora.

  13. Accumulation effects in modulation spectroscopy with high-repetition-rate pulses: Recursive solution of optical Bloch equations

    Science.gov (United States)

    Osipov, Vladimir Al.; Pullerits, Tõnu

    2017-10-01

    Application of the phase-modulated pulsed light for advance spectroscopic measurements is the area of growing interest. The phase modulation of the light causes modulation of the signal. Separation of the spectral components of the modulations allows to distinguish the contributions of various interaction pathways. The lasers with high repetition rate used in such experiments can lead to appearance of the accumulation effects, which become especially pronounced in systems with long-living excited states. Recently it was shown that such accumulation effects can be used to evaluate parameters of the dynamical processes in the material. In this work we demonstrate that the accumulation effects are also important in the quantum characteristics measurements provided by modulation spectroscopy. In particular, we consider a model of quantum two-level system driven by a train of phase-modulated light pulses, organized in analogy with the two-dimensional spectroscopy experiments. We evaluate the harmonics' amplitudes in the fluorescent signal and calculate corrections appearing from the accumulation effects. We show that the corrections can be significant and have to be taken into account at analysis of experimental data.

  14. Ammonium sulphate induced stress related alterations in the respiratory epithelium of the airbreathing organ of the catfish Heteropneustes fossilis (Bloch)

    Digital Repository Service at National Institute of Oceanography (India)

    Paul, V.I.; Banerjee, T.K.

    In this paper, histopathological changes in the inner lining of the accessory respiratory organ of Heteropneustes fossilis following exposure to sublethal concentration (0.2 gl sup(-1)) of ammonium sulphate (3 mg l sup(-1) total ammonia-N) has been...

  15. Spatial morphometric plasticity of spirlin Alburnoides bipunctatus (Bloch, 1782 phenotype from the Nišava River, Serbia, Danube basin

    Directory of Open Access Journals (Sweden)

    Živković, D.

    2011-09-01

    Full Text Available Variation of 22 morphometric and 4 meristic characters of the species Alburnoides bipuuctatus from Nišava River were analyzed. Specimens were collected from four sampling stations along the putative mesohabitat gradient of river influence and were grouped into the categories with similar total length. Morphometric characters varied immensely between different mesohabitats outlining morphometric plasticity. Among several morphometry features that were influenced by different mesohabitats the most observable differences were noted for: postocular distance, anal fin height, minimal body height and preanal length. Regarding the meristic features, number of soft rays in the anal fin did varied significantly among sampling stations while fourth hard ray in the anal fin for this species was reported for the first time ever. Pharyngeal teeth formula of spirlin also showed variability across different mesohabitats. In conclusion, it appears that spirlin express a big morphological plasticity in relation to spatial and mesohabitat distribution and there is a possibility that spirlin from Nišava River is a complex of neospecies in formation/morphotypes/ecotypes rather than a single population.

  16. Feeding of Hoplias aff. malabaricus (Bloch, 1794 and Oligosarcus robustus Menezes, 1969 in a lagoon under estuarine influence, Pelotas, RS

    Directory of Open Access Journals (Sweden)

    Fabiano Corrêa

    2009-09-01

    Full Text Available The objective of the present paper was to study the diets of Hoplias aff. malabaricus and Oligosarcus robust in “Pequena Lagoon” and evaluate the importance of estuarine organisms in the feeding of freshwater fish. A total of twelve food categories were identified and it was established that the fish resource was the most frequent in the diet of both species. Euryhaline fish such as Mugil platanus mullets and Odontesthes argentinensis silversides were common items in the diets of these two species, which included not only freshwater fish but also euryhaline fish from the adjacent estuarine zone, integrating both resources in the food chain.

  17. A new distributional record of alligator pipefish, Syngnathoides biaculeatus (Bloch, 1785) along Goa, central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Sanaye, S.V.; Rivonker, C.U.; Ansari, Z.A.; Sreepada, R.A.

    re´gulations hormonales de l’incubation chez un Verte`bre male: recherches sur la reproduction de l’Hippocampe. PhD thesis, l’Universite´ de Bordeaux, France. (1967). 36 Tipton K & Bell S S., Foraging patterns of two syngnathid fishes: importance... of harpacticoid copepods. Mar Ecol Prog Ser., 47 (1988) 31–43. 37 Do H H, Truong S K & Ho T H., Feeding behaviour and food of seahorses in Vietnam. In Proceedings of the 3rd International Conference on the Marine Biology of the South China Sea edited...

  18. Toxicity of puffer fish: two species (Lagocephalus laevigatus, linaeus 1766 and Sphoeroides spengleri, Bloch 1785 from the Southeastern Brazilian coast

    Directory of Open Access Journals (Sweden)

    J. S. Oliveira

    2003-01-01

    Full Text Available In Brazil, where puffer fish are considered poisonous, there are few documented cases on human consumption and consequent poisoning. In this study, toxicity of two puffer fish species from the Brazilian coast was examined. Specimens of Sphoeroides spengleri and Lagocephalus laevigatus were caught in São Sebastião Channel (North coast of São Paulo State, Brazil between January 1996 and May 1997. Acidic ethanol extracts from muscle and skin plus viscera were tested for mice acute toxicity using the standard method of Kawabata. Polar extracts of S. spengleri showed high toxicity up to 946 MU/g. Extracts from L. laevigatus showed very low levels of toxicity, never exceeding 1.7 MU/g. All extracts from both species blocked amielinic nerve fiber evoked impulses of crustacean legs; this effect reverted on washing similar to the standard tetrodotoxin TTX. The aqueous extract solutions were partially purified using an ionic exchange column (Amberlit GC-50 followed by treatment with activated charcoal (Norit-A. The presence of TTX and their analogs in the semi-purified extracts were confirmed by HPLC and mass spectrometry (MALDI-TOF.

  19. Rohdella amazonica n. sp. (Aspidogastrea: Aspidogastridae) from the Amazoninan banded puffer fish Colomesus psittacus (Bloch & Schneider, 1801).

    Science.gov (United States)

    Giese, E G; Silva, M V O; Videira, M N; Furtado, A P; Matos, E R; Gonçalves, E C; Melo, F T V; Santos, J N

    2015-05-01

    Aspidogastreans are commonly found infecting freshwater and marine molluscs, teleosts fishes and freshwater turtles. The subclass comprises four families - Rugogastridae Schell 1973, Stichocotylidae Faust & Tang 1936, Multicalycidae Gibson & Chinabut 1984 and Aspidogastridae Poche 1907 - and it is characterized by the presence of a ventral adhesive disc divided into rows of alveoli. In the current work, using light and scanning electron microscopy and molecular approaches, a new species of Aspidogastridae of the genus Rohdella Gibson & Chinabut, 1984, is described as a parasite of Colomesus psittacus in Brazil. The new taxon is distinguishable by the presence of oesophageal glands, teguments covered by ciliated papillae, and the position and shape of the hermaphroditic duct. The present work describes the third species of the genus Rohdella, thereby adding new morphological and molecular data regarding Aspidogastridae.

  20. Some remarks on the South American Pimelodid catfish usually known by the name of Phractocephalus Hemiliopterus (Bloch & Schneider) (Pimelodidae, Siluriformes)

    NARCIS (Netherlands)

    Boeseman, M.

    1983-01-01

    The present note draws attention to the first substantiated Phractocephalus record from Surinam, to the customary incorrect spellings of the specific name since Cuvier, 1829 and to an unexpected ontogenetic change in the striking colour pattern of this species.

  1. Quantum Analysis of a Microcavity-Tuned Bloch Oscillator for Tunable Spontaneous Emission and Absorption of Terahertz Radiation

    Science.gov (United States)

    2007-06-20

    interface impurities with randomly distributed interface roughness, it can be shown7 that fkk ′ (t) is expressed as fkk ′ (t) = VKK′ e − i h̄ [η(K)−η(K...only the term with ly = 1 need be retained in Eqs. (10) and (11). Then, in utilizing fkk ′ (t) from Eq. (9) in Eq. (6), and anticipating the ensemble...average over the randomly distributed interface roughness coordinates, which renders the ensemble average over the fkk ′ (t) term on the right-hand

  2. A preliminary survey on parasitic occurrence in indigenous climbing perch, Anabas testudineus (Bloch, 1972 from West Bengal state of India

    Directory of Open Access Journals (Sweden)

    Basudev Mandal

    2016-08-01

    Full Text Available Objective: To describe the parasitic infestations of Anabas testudineus (A. testudineus collected from three different fish producing districts of West Bengal state in India. Methods: A total number of 75 specimens of A. testudineus were collected from different floodplain areas of West Bengal, India. These specimens were examined for parasites using established techniques after measuring basic morphometric parameters. Results: A total 165 individual of 20 parasites (13 ectoparasites and 7 endoparasites belonging to 7 phyla were recorded from 64 infected A. testudineus. Among the observed parasites, 8 were protozoan including 3 ciliates; 2 monogenic trematodes, 2 strigeidid trematodes, 1 nematode, 3 crustaceans, 3 myxozoans and 1 echinorhynchus acanthocephalan parasites. The quantitative abundance of parasites were highest in gill (37% followed by body outer layer (35% and intestine (28%. District wise quantitative count of parasites in different investigated organ from A. testudineus revealed that North 24 Parganas is highly infected followed by West Midnapore and East Midnapore. The highest prevalence (% and mean abundance of parasitic occurrence was observed in North 24 Parganas followed by West Midnapore and East Midnapore. The highest mean intensity was found at West Midnapore followed by North 24 Parganas and East Midnapore. Conclusions: Especially West Bengal state of India, inland culture and capture fishery mainly rural based and operated by poor farmers. Developing right kind of interventions and management practice can prevent adverse impact of diseases and assist poor farmers for sustainable production.

  3. Growth and survival of a diallel cross for five strains of climbing perch (Anabas testudineus Bloch, 1792 in Thailand

    Directory of Open Access Journals (Sweden)

    Nitikorn Piwpong

    2016-09-01

    Full Text Available A complete diallel cross experiment was conducted with five strains of climbing perch (Anabas testudineus representing three wild populations collected from main river basins in Thailand and two farm populations in southern Thailand. Growth performance was recorded from 794 individually tagged progeny of the 24 different strain combinations after a grow-out period of about 130 d in an earthen pond. Least squares means of body weight at harvest and absolute growth rates were computed for each strain combination. The Chumphon strain showed the highest growth performance (81.1 ± 1.1 g. The Surat Thani × Chumphon (the first strain represents the sire showed the highest survival (65.4± 25.50% among the purebreds and the crossbreds. The domesticated gene pool had much better growth in aquaculture than the wild gene pool. The correlation between the least squares means of body weight and the survival rates in the 24 strain combinations was 0.51 (p < 0.05. The mean heterosis of all crossbreds across traits was negative (−10.2± 22.7%. Heterosis appeared to decrease when different gene pools were crossed. This suggests that there may be outbreeding depression. The advantage of crossbred performance was clearly not shown in the study.

  4. DOE Zero Energy Ready Home Case Study: Amerisips Homes — Miller-Bloch Residence, Johns Island, SC

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-09-01

    For this DOE Zero Energy Ready Home that won a Custom Builder award in the 2014 Housing Innovation Awards, the builder uses structural insulated panels to construct the entire building shell, including the roof, walls, and floor of the home.

  5. Age, growth and mortality of dog snapper Lutjanus jocu (Bloch & Schneider, 1801 in the northeast coast of Brazil

    Directory of Open Access Journals (Sweden)

    Sérgio de Magalhães Rezende

    2004-06-01

    Full Text Available The age and growth of Lutjanus jocu was assessed through readings of growth marks in sagitta otoliths. From August 1996 to March 2000, fish were sampled (n=3.539 in the northeast portion of the Brazilian Exclusive Economic Zone. Sagitta otoliths were extracted from a sub sample of 216 individuals caught around the oceanic bank Sirius (03°59' s; 35°59' w and over continental shelf from Ceará (05°03's; 36°02'w to Bahía States (09°01's; 35°12'w. Opaque bands, presumed to be annual, were observed on whole (n= 210 and sectioned (n= 197 otoliths, showing ages from 0 to 20 and from 0 to 25 years respectively. The von Bertalanffy growth model was fit to length-at-age data resulting in the values of Li= 77.22 cm, K= 0.110 and t0= -3.73. Incremental widths from the first to twentieth opaque band on sectioned otoliths (n = 39 were used on back calculation of length-at-ages and the estimated values were Li= 71,20 cm, K= 0.112 e t0= -4.32. Otolith reading from sections is a reliable technique for aging L. jocu, which presented medium to high longevity and slow growth. Total mortality (Z estimated by the catch curve was 0.134 corresponding to an annual survival rate of 87.5%. The natural mortality (M estimated by the Ault et al. (1998 methodology was 0.12 for 25 years of longevity.Idade e crescimento do Lutjanus jocu foi determinada através da leitura de marcas de aposição em otólitos sagittae. 216 indivíduos, capturados no entorno da montanha oceânica Sirius e na plataforma continental do Ceará (05°03's; 36°02'w até a Bahia (09°01's; 35°12'w tiveram seus otólitos extraídos. Marcas opacas que provavelmente formam-se anualmente foram observadas em otólitos inteiros (n=210 e em otólitos seccionados (n=197 apresentando peixes com idades entre 0 a 20 e 25 anos respectivamente. O modelo de crescimento de Bertalanffy ajustado por métodos não lineares dos mínimos quadrados aos dados de idade e comprimento resultou em valores de Li= 77,22 cm, K= 0,110 and t0= -3,73. Medidas incrementais da 1ª a 20ª marca opaca em otólitos seccionados (n=39 foram usadas para retrocalcular os comprimentos e as respectivas idades resultando em valores de Li= 71,20 cm, K= 0,112 e t0= -4,32. Leitura de otólitos seccionados de L. jocu é uma técnica confiável para a determinação da idade e crescimento desta espécie, que apresentou longevidade de média a alta com crescimento lento. A taxa de mortalidade total (Z estimada através da curva de captura foi 0,134 correspondendo a 87,5% de sobrevivência anual. A mortalidade natural (M calculada pelo método de Ault et al. (1998 foi 0,12 para uma longevidade de 25 anos.

  6. Prism coupling method to excite and analyze Floquet-Bloch modes in linear and nonlinear waveguide arrays.

    Science.gov (United States)

    Rüter, Christian E; Wisniewski, J; Kip, Detlef

    2006-09-15

    We demonstrate an experimental method for the direct measurement of band structures of one-dimensional periodic optical media. With the help of a prism coupler that is used in a retroreflective scheme, the allowed bands of a waveguide array in lithium niobate are determined and the results are compared with numerical calculations. Furthermore, we demonstrate the suitability of this method to measure propagation constants of extended nonlinear modes inside the forbidden gap.

  7. JENIS PAKAN ALAMI LARVA IKAN BETOK (Anabas testudineus Bloch DI PERAIRAN RAWA MONOTON DANAU BANGKAU, KALIMANTAN SELATAN

    Directory of Open Access Journals (Sweden)

    Rukmini Rukmini

    2016-03-01

    Full Text Available Usaha pembenihan ikan merupakan alternatif pemecahan masalah untuk mengatasi kesenjangan antara ketersediaan dan kebutuhan benih dalam budidaya ikan. Keberhasilan usaha pembesaran ikan betok dibatasi oleh tingkat kelangsungan hidup larva bagi pertumbuhan dan jenis pakan alami larva ikan di habitatnya. Tujuan penelitian ini adalah untuk mengetahui jenis dan kelimpahan pakan alami yang dikonsumsi larva ikan betok di perairan rawa monoton Danau Bangkau Kalimantan Selatan. Penelitian dilaksanakan pada bulan Desember 2011-Januari 2012. Pengambilan sampel pakan dan larva dilakukan pada dua tempat yang berbeda pada kedalaman 30 cm. Hasil penelitian menunjukkan jenis plankton yang dikonsumsi oleh larva ikan betok berubah sesuai dengan ukuran bukaan mulut ikan dan kelimpahan plankton di perairan. Jenis plakton dominan yang dimakan oleh larva betok yaitu Mougeotia sp. 265 sel/L diikuti oleh Coconeis sp. 246 sel/L, Keratella sp. 174 sel/L, Chlorococcum sp. 110 sel/L, Brachionus sp. 98 sel/L, dan Navicula sp. 47 sel/L. Jenis plakton dominan yang dimakan berubah sesuai dengan umur larva.   Business seeding fish an alternative problem-solving to overcome the gap between availability and needs seeds. The success of the business of enlargement climbing fish bounded by the degree of continuity larvæ live for growth and a kind of natural fish larvae feed on their habitat. The purpose of this research was to know the type of plankton that were consumed by climbing perch fish larvae in the waters of the monotonous swamp of Danau Bangkau. The research was conducted from December, 2011- January, 2012. The sample feed and larvæ carried on two different places at the depth of 30 cm. The result showed plankton species consumed by climbing fish larvae change according to size openings mouth fish and abundance plankton in waters. A kind of plankton dominant which are eaten by the climbing larvæ  namely Mougeotia sp. 265 cells/L followed by Coconeis sp. 246 cells/L, Keratella sp. 174 cells/L, Chlorococcum sp. 110 cells/L, Brachionus sp. 98 cells/L, and Navicula sp. 47 cells/L. A kind of plankton dominant eaten changed in accordance with the age of larvæ.

  8. Environ: E00413 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available lucose [CPD:C00031], Starch [CPD:C00369] Bletilla striata [TAX:78707] Orchidaceae (orchid family) Bletilla s...triata corm (dried) Crude drugs [BR:br08305] Monocot plants Orchidaceae (orchid family) E00413 Bletilla striata corm ...

  9. Fungal infection in freshwater fishes of Andhra Pradesh, India ...

    African Journals Online (AJOL)

    A total of 17 isolates of fungi were isolated from diseased fishes which belong to five species namely Saprolegnia diclina, Saprolegnia ferax, Saprolegnia hypogyana, Saprolegnia parasitica and Achlya americana. All these fungi were isolated from six different species of fresh water fishes viz. Channa stratius, Channa ...

  10. Browse Title Index

    African Journals Online (AJOL)

    Items 351 - 390 of 390 ... Vol 15, No 1 (2000), The Ecology of Endohelminth Parasites of Fish in the Driffield Trout Stream, Yorkshire, England, Abstract. C. E. OKAKA, E. A. ... Vol 15, No 1 (2000), The Length-Weight Relationships of Snake-Head (Channa channa) from the Freshwater Swamps of Niger Delta, Nigeria, Abstract.

  11. Journal of Aquatic Sciences - Vol 15, No 1 (2000)

    African Journals Online (AJOL)

    The Length-Weight Relationships of Snake-Head (Channa channa) from the Freshwater Swamps of Niger Delta, Nigeria · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL ... Parasitic Infection of the Nile Perch Lates niloticus (L) in River Kaduna . EMAIL FULL TEXT EMAIL FULL TEXT

  12. Cytochrome b gene reveals panmixia among Japanese Threadfin Bream, Nemipterus japonicus (Bloch, 1791) populations along the coasts of Peninsular Malaysia and provides evidence of a cryptic species.

    Science.gov (United States)

    Lim, Hong-Chiun; Ahmad, Abu Talib; Nuruddin, Ahmad Adnan; Mohd Nor, Siti Azizah

    2016-01-01

    We evaluated genetic differentiation among ten presumed Japanese threadfin bream, Nemipterus japonicus populations along the coast of Peninsular Malaysia based on the partial sequence of the mitochondrial cytochrome b gene (982 bp). Genetic divergences (Kimura-2 parameter) ranged from 0.5% to 0.8% among nine of the ten populations while these nine populations were 4.4% to 4.6% diverged from the Kuala Besar population located at the Northeast coast. The constructed Neighbour Joining (NJ) phylogenetic trees based on haplotypes showed the Kuala Besar population forming an isolated cluster. The Analysis of Molecular Variance (AMOVA) of the ten populations a priori assigned into four regions, revealed that most of the variation occurred within population with a fairly low but significant level of regional differentiation (FST = 0.07, p 0.05 and FCT = 0.07, p Malaysia were panmictic. However, the Kuala Besar population, although morphologically identical was composed of a genetically discrete taxon from the rest. These findings are important contributions in formulating sustainable fishery management policies for this important fishery in Peninsular Malaysia.

  13. Female morphology of Philometra hyderabadensis Rasheed, 1963 (Nematoda: Philometridae), a little-known parasite of the catfish Wallago attu Bloch & Schneider in India, as revealed by SEM observations

    Czech Academy of Sciences Publication Activity Database

    Moravec, František; Chavan, S. P.

    2012-01-01

    Roč. 83, č. 2 (2012), s. 117-122 ISSN 0165-5752 R&D Projects: GA ČR GBP505/12/G112 Institutional research plan: CEZ:AV0Z60220518 Keywords : Philometra * Wallago * India Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.260, year: 2012

  14. Biologia pesqueira das raias Dasyatis guttata (bloch & schneider, 1801) e Dasyatis Americana Hildebrand & Schroeder, 1928, no Estado do CearÃ

    OpenAIRE

    Guelson Batista da Silva

    2005-01-01

    As raias das espÃcies Dasyatis guttata e Dasyatis americana constituem importantes recursos pesqueiros no Estado do CearÃ. O objetivo geral desta DissertaÃÃo à estudar a biologia pesqueira dessas espÃcies com vistas ao uso das informaÃÃes como constituintes de eventuais medidas de gerenciamento de sua exploraÃÃo. Dentro desse contexto geral, foram abordados aspectos relacionados com a biometria e suas relaÃÃes morfomÃtricas, dieta alimentar e reproduÃÃo, quanto ao comprimento mÃdio na 1 matu...

  15. Biogeography and comparative cytogenetics between two populations of Hoplias malabaricus (Bloch, 1794 (Ostariophysi: Erythrinidae from coastal basins in the State of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Uedson Pereira Jacobina

    Full Text Available The species Hoplias malabaricus is a predator fish found in nearly all cis-Andean basins. From a cytogenetic point of view, this species comprises, at least, seven differentiated karyomorphs. Several localities have been formerly analyzed in Brazil, however, some regions, such as Bahia State, remain underrepresented. Recently, the Brazilian Environment Ministry classified both Itapicuru and Contas river basins (entirely located within Bahia territory as priority conservation areas, whose biodiversity status lacks enough information. Therefore, the goal of the present work was to characterize, cytogenetically, populations of H. malabaricus from both basins, by using conventional staining, Ag-NOR and C-banding techniques. All specimens presented a diploid number of 2n = 40 with metacentric/submetacentric chromosomes, without differences between sexes, thereby representing the so-called "karyomorph F". The first metacentric pair presented a remarkably larger size in relation to the other pairs. The NORs were multiple, comprising the terminal region on long arms of two chromosomal pairs in both populations. However, the C-banding pattern was somewhat distinguishable between samples. Although sharing heterochromatic blocks at centromeric region of all chromosomes, the population from Itapicuru River basin appeared to have some more conspicuous blocks than those observed in the population from Contas River basin. The similar karyotype observed in both populations suggests a common geological history between them. The present results represent an advance in the knowledge about the cytogenetic pattern of H. malabaricus populations from poorly studied basins.

  16. The effects of temperature on gastric emptying time of malabar blood snapper (Lutjanus malabaricus, Bloch & Schneider 1801) using X-radiography technique

    Science.gov (United States)

    Mazumder, Sabuj Kanti; Ghaffar, Mazlan Abd.; Das, Simon Kumar

    2015-09-01

    Water temperature can influence the metabolic rate of ectothermal animal such as, fish. This study aims to investigate the gastric emptying time (GET) of malabar blood snapper (L. malabaricus) at different temperature (22, 26, 30, 34°C) fed with commercial diet pellet. The gastric emptying times at different temperatures were determined X-radiographically, using barium sulfate (BaSO4) as a contrast medium food marker. The food marker and X-radiography showed that initial voidance of fecal matter began 4-8 h after feeding at all temperature. The fastest GET (18 h) was obsereved at 30°C, whereas the longest (28 h) GET was seen at 22°C. GET was increased with increasing temperature up to 30°C whereas decreased at extreme (34°C) and stress temperature (22°C). The findings of this study suggest to culture L. malabaricus at 26-30°C with commercial diet pellet as this temperature ranges escalate the faster digestion process which may contribute faster growth rate of this commercially important fish species. Overall, the data obtained from this study may have important consequences for optimization of commercial production of malabar blood snapper.

  17. Molecular and cytogenetic analyses of cryptic species within the Synbranchus marmoratus Bloch, 1795 (Synbranchiformes: Synbranchidae grouping: species delimitations, karyotypic evolution and intraspecific diversification

    Directory of Open Access Journals (Sweden)

    Ricardo Utsunomia

    Full Text Available The fish species Synbranchus marmoratushas been reported to exist as a species complex due to high intraspecific karyotypic variability in spite of the difficulty or impossibility to distinguish them using morphological traits alone. The goal of this work was to use cytogenetic and molecular methods to determine the species delimitations and understand the karyoevolution ofS. marmoratususing samples collected from distinct Brazilian localities. Among the analyzed specimens, a large degree of cytogenetic variation related to diploid numbers and karyotype structure was observed, with karyotypes showing 2n=42, 44 and 46 chromosomes. In addition, using sequences of three mitochondrial genes, the phylogenetic relationships between every sample with a known karyotype were determined, which revealed significant nucleotide divergence among the karyomorphs. Also, the analyses indicate that chromosomal rearrangements occurred independently within the distinct lineages of S. marmoratuscomplex, which resulted in the appearance of distinct karyotypic variants in a non-linear fashion related to diploid numbers and in the appearance of similar non-homologous chromosomes. Finally, the integration of both molecular cytogenetic and phylogenetic approaches allowed the determination of specific chromosomes possibly involved in rearrangements and a better understanding about the evolutionary processes involved in the differentiation ofSynbranchusgenus.

  18. Screening probiotic candidates for a mixture of probiotics to enhance the growth performance, immunity, and disease resistance of Asian seabass, Lates calcarifer (Bloch), against Aeromonas hydrophila.

    Science.gov (United States)

    Lin, Hsueh-Li; Shiu, Ya-Li; Chiu, Chiu-Shia; Huang, Shih-Ling; Liu, Chun-Hung

    2017-01-01

    Six bacteria, including, Lactobacillus casei M15, Lac. plantarum D8, Lac. pentosus BD6, Lac. fermentum LW2, Enterococcus faecium 10-10, and Bacillus subtilis E20, and one yeast, Saccharomyces cerevisiae P13 were selected as probiotics for Asian seabass, Lates calcarifer, by tracking the growth performance and disease resistance of fish against Aeromonas hydrophila in the first trial. The probiotic efficiency screening results showed that B. subtilis E20 and Lac. pentosus BD6, and S. cerevisiae P13 and Lac. fermentum LW2 respectively improved either the growth performance or disease resistance. Therefore, these four probiotics were then selected to prepare a probiotics mixture, and this was incorporated in equal proportions into diets for Asian seabass at levels of 0 (control), and 106 (MD6), 107 (MD7), 108 (MD8), and 109 (MD9) colony-forming units (cfu) (kg diet)-1. A synergistic effect of the combined probiotics was investigated in this study, and the probiotics mixture was able to improve both the growth performance and health status of fish. After 56 days of feeding, fish fed the MD9 diet had a higher final weight and percentage of weight gain. In addition, protein contents in the dorsal muscle of fish fed the MD8 and MD9 diets were significantly higher compared to the control. For the pathogen challenge test, fish fed the MD7, MD8, and MD9 diets had significantly lower cumulative mortalities after A. hydrophila infection compared to those of fish fed the control and MD6 diets, which might have been due to increased respiratory bursts, decreased superoxide dismutase activity in leucocytes, and increased phagocytic activity. Therefore, we considered that the probiotics mixture could adequately provide probiotic efficiency for Asian seabass, and the diet containing 109 cfu (kg diet)-1 probiotic mixture is recommended to improve the growth and health status of Asian seabass. Copyright © 2016. Published by Elsevier Ltd.

  19. Some observations on the morphometry and biology of Psettodes erumei (Bloch) and Pseudorhombus arsius (Hamilton-Buchanan) from the Goa region

    Digital Repository Service at National Institute of Oceanography (India)

    Menezes, M.R.

    The metric and meristic characters of Psettodes erumei and Pseudorhombus arsius from the nearshore waters of Goa have been studied. The meristic characters of these two species showed considerable variations. However, the number of vertebrae in P...

  20. "Candidatus Similichlamydia laticola", a novel Chlamydia-like agent of epitheliocystis in seven consecutive cohorts of farmed Australian barramundi, Lates calcarifer (Bloch.

    Directory of Open Access Journals (Sweden)

    Megan C Stride

    Full Text Available Six consecutively hatched cohorts and one cohort of pre-hatch eggs of farmed barramundi (Lates calcarifer from south Australia were examined for Chlamydia-like organisms associated with epitheliocystis. To identify and characterise the bacteria, 59 gill samples and three pre-hatch egg samples were processed for histology, in situ hybridisation and 16S rRNA amplification, sequencing and comprehensive phylogenetic analysis. Cases of epitheliocystis were observed microscopically and characterised by membrane-enclosed basophilic cysts filled with a granular material that caused hypertrophy of the epithelial cells. In situ hybridisation with a Chlamydiales-specific probe lead to specific labelling of the epitheliocystis inclusions within the gill epithelium. Two distinct but closely related 16S rRNA chlamydial sequences were amplified from gill DNA across the seven cohorts, including from pre-hatch eggs. These genotype sequences were found to be novel, sharing 97.1 - 97.5% similarity to the next closest 16S rRNA sequence, Ca. Similichlamydia latridicola, from Australian striped trumpeter. Comprehensive phylogenetic analysis of these genotype sequences against representative members of the Chlamydiales order and against other epitheliocystis agents revealed these Chlamydia-like organisms to be novel and taxonomically placed them within the recently proposed genus Ca. Similichlamydia. Following Fredricks and Relman's molecular postulates and based on these observations, we propose the epitheliocystis agents of barramundi to be known as "Candidatus Similichlamydia laticola" (sp. nov..

  1. Genetic variation in the mitochondrial genome of the giant grouper Epinephelus lanceolatus (Bloch, 1790 and its application for the identification of broodstock

    Directory of Open Access Journals (Sweden)

    Seng S. Cheng

    2015-11-01

    Full Text Available Mitochondrial DNA (mtDNA markers are ideal for the validation of maternal inheritance and the identification of brood-stock in aquaculture breeding programs. The complete mitochondrial genomes of 11 species of grouper are currently available at the GenBank. This study was directed towards the characterization of mtDNA loci which can be applied for identification of interspecific F1 hybrids developed from Epinephelus fuscoguttatus and Epinephelus lanceolatus in aquaculture breeding programs. DNA was extracted from the fin clip of one specimen of E. lanceolatus which the source of sperm for the artificial spawning of the interspecific F1 hybrid E. fuscoguttatus × E. lanceolatus. Specific primers were designed to amplify the DNA after comparative analysis of the mtDNA genomes available at the GenBank. The primers were applied to test for cross-amplification in F1 hybrids as well as in the maternal parent E. fuscoguttatus (Forsskål, 1775 and the genetically related species Epinephelus coioides and Epinephelus corallicola (Valenciennes, 1828. DNA sequence analysis revealed that the Malaysian variety of E. lanceolatus exhibited variation at 11 of the 13 ORFs when compared to the variety from Taiwan. A distinct segmented duplication was observed in the D-loop region which was determined to be unique to the E. lanceolatus specimen obtained from Sabah, Malaysia. Cross amplification of mtDNA loci in the groupers E. fuscoguttatus, E. coioides, E. corallicola and the F1 hybrid of E. fuscoguttatus × E. lanceolatus revealed distinct profiles for each of the species with a clear indication that mtDNA were inherited from the maternal parent of the F1 hybrid.. mtDNA loci can be applied by fish breeders to determine interspecific hybridization events.

  2. Avaliação de metazoarios parasitos de Hoplias malabaricus (Bloch, 1794) (Pisces: Erythrinidae) como potenciais indicadores de qualidade ambiental

    OpenAIRE

    Lincoln Lima Correa

    2009-01-01

    Resumo: Este estudo teve como objetivo a associação entre os índices hematológicos de Hoplias malabaricus (traíra), o parasitismo por monogeneas e outras espécies de metazoários e os fatores ambientais. O estudo ocorreu nas lagoas do CEPTA/ICMBio, localizada no município de Pirassununga, SP (21º55'55"S e 47º22'37"W), no período de fevereiro de 2008 a março de 2009 em 187 traíras. Verificou-se que os parâmetros sanguíneos não sofreram alterações significativas em relação ao estágio de maturaçã...

  3. The effects of temperature on gastric emptying time of malabar blood snapper (Lutjanus malabaricus, Bloch & Schneider 1801) using X-radiography technique

    Energy Technology Data Exchange (ETDEWEB)

    Mazumder, Sabuj Kanti, E-mail: sabujsau@gmail.com [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Ghaffar, Mazlan Abd., E-mail: magfish05@yahoo.com [Marine Ecosystem Research Centre (EKOMAR), Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Institute of Tropical Aquaculture, University of Malaysia Terengganu, 21030 Kuala Terengganu (Malaysia); Das, Simon Kumar, E-mail: skdas-maa@yahoo.com [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Marine Ecosystem Research Centre (EKOMAR), Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-09-25

    Water temperature can influence the metabolic rate of ectothermal animal such as, fish. This study aims to investigate the gastric emptying time (GET) of malabar blood snapper (L. malabaricus) at different temperature (22, 26, 30, 34°C) fed with commercial diet pellet. The gastric emptying times at different temperatures were determined X-radiographically, using barium sulfate (BaSO{sub 4}) as a contrast medium food marker. The food marker and X-radiography showed that initial voidance of fecal matter began 4-8 h after feeding at all temperature. The fastest GET (18 h) was obsereved at 30°C, whereas the longest (28 h) GET was seen at 22°C. GET was increased with increasing temperature up to 30°C whereas decreased at extreme (34°C) and stress temperature (22°C). The findings of this study suggest to culture L. malabaricus at 26-30°C with commercial diet pellet as this temperature ranges escalate the faster digestion process which may contribute faster growth rate of this commercially important fish species. Overall, the data obtained from this study may have important consequences for optimization of commercial production of malabar blood snapper.

  4. Physiologic implications of inter-hormonal interference in fish: lessons from the interaction of adrenaline with cortisol and thyroid hormones in climbing perch (Anabas testudineus Bloch).

    Science.gov (United States)

    George, Nimta; Peter, Valsa S; Peter, M C Subhash

    2013-01-15

    Adrenaline and cortisol, the major stress hormones, are known for its direct control on stress response in fish. Likewise, as an important stress modifier hormone, thyroid hormone has also been implicated in stress response of fish. We tested whether the hypothesis on the phenomenon of inter-hormonal interference, a process that explains the hormonal interactions, operates in fish particularly between adrenaline, cortisol and thyroid hormones. To achieve this goal, indices of acid-base, osmotic and metabolic regulations were quantified after adrenaline challenge in propranolol pre-treated air-breathing fish (Anabas testudineus). Short-term adrenaline (10 ng g(-1)) injection for 30 min produced a rise in plasma cortisol without affecting plasma T(3) and T(4). On the contrary, blocking of adrenaline action with a non-selective blocker, propranolol (25 ng g(-1)) for 90 min reduced plasma cortisol along with plasma T(4) and that indicate a possible interference of these hormones in the absence of adrenaline challenge. Similarly, a reduction in plasma T(3) was found after adrenaline challenge in propranolol pre-treated fish and that suggests a functional synergistic interference of adrenaline with T(3). Adrenaline challenge in these fish, however, failed to abolish this propranolol effect. The remarkable systemic hypercapnia and acidosis by propranolol pre-treatment were reversed by adrenaline challenge, pointing to a direct action of adrenaline on acid-base indices probably by a mechanism which may not require β-adrenergic receptor systems. Interestingly, the prominent adrenaline-induced hyperglycemia, hyperlactemia and hyperuremea were not altered by propranolol treatment. Similarly, adrenaline challenge promoted and propranolol reduced the osmotic competencies of the gills, kidneys and liver of this fish as evident in the sodium and proton pump activities. The modified physiologic actions of adrenaline and its modified interaction with THs and cortisol in blocked fish indicate an interaction of adrenaline with cortisol and THs. Our physiologic evidences thus support the hypothesis of the phenomenon of inter-hormonal interference. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Reproductive dynamics and population structure of Hoplias aff. malabaricus (Bloch, 1794 (Characiformes, Erythrinidae in the dam lake of the Taperoá River Basin, Paraíba

    Directory of Open Access Journals (Sweden)

    Maria Cristina Crispim

    2009-06-01

    Full Text Available This work aims to verify the reproductive dynamics and growth of the Hoplias aff. malabaricus species in the Taperoá II dam lake (07º11’44”S, 07º13’44”S, located in the basin of the River Taperoá in the Cariri region of Paraiba. Sixty-seven individuals were collected (August-December 2002, January-February, May and June 2003 by means of gillnets and cast nets. The interference of the rain regimen in the reproductive behavior and the structure of growth of the species were observed after the macrocospic analysis of the gonads of the collected units.

  6. Food and feeding habits of king weakfish, Macrodon ancylodon (Bloch & Schneider, 1801 caught in the southern coast of Brazil (lat, 29º to 32ºs

    Directory of Open Access Journals (Sweden)

    Anastácio Afonso Juras

    1985-01-01

    Full Text Available Macrodon ancylodon was obtained from landings in Santos Port (São Paulo State of fish caught monthly by commercial vessels, on the southern coast of Brazil during September 1976 to August 1977. The measurements of total lenght, total weight determination of sex and maturity stages were made. The food items found in stomach contents were: shrimp (Artemesia longinaris, fishes (Paralonchurus brasiliensis, Macrodon ancylodon, Trichirus lepturus, Gadidae, Engraulidae, molluscs (Loliginidae, Bivalvia and Stomatopoda. Widening of food spectrum was observed in winter. The index of preponderance showed that immature females, immature and mature males fed predominantly on shrimp, while mature females fed mainly on fishes. During spring and summer (spawning season M. ancylodon exhibited relatively low percentage of full stomachs. Cannibalism was encountered more intensively for mature fish.

  7. Efficacy of exogenous hormone (GnRHa) for induced breeding of climbing perch Anabas testudineus (Bloch, 1792) and influence of operational sex ratio on spawning success.

    Science.gov (United States)

    Mandal, Babita; Kumar, Rajesh; Jayasankar, P

    2016-08-01

    The climbing perch, Anabas testudineus, is an air-breathing fish having great consumer preference as a food fish and is considered a prime candidate species for aquaculture. Spawning success is an important issue while using hormones for captive induced breeding. In the first experiment, a trial was conducted to assess the efficacy of a synthetic Gonadotropin Releasing Hormone analog (sGnRHa) on the spawning success of climbing perch. Female fish were administered six different doses each with a single intramuscular injection of sGnRHa hormone at 0.002 (TOD1), 0.005 (TOD2), 0.01 (TOD3), 0.015 (TOD4), 0.02 (TOD5), 0.03 (TOD6) μg/g body weight. Similarly, males were administered half of the hormone dose of females in all the respective treatment groups. The greatest (Pclimbing perch. For this study a different female to male ratio (1:1, 1:2, 1:3 and 1:4) and male to female ratio (1:1, 1:2 and 1:3) were used. There were a greater (Pclimbing perch. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Dietary amino acid L-tryptophan requirement of fingerling Indian catfish, Heteropneustes fossilis (Bloch), estimated by growth and haemato-biochemical parameters.

    Science.gov (United States)

    Ahmed, Imtiaz

    2012-08-01

    An 8-week feeding trial was conducted to determine the dietary tryptophan requirement of fingerling Indian catfish, Heteropneustes fossilis (6.10 ± 1.15 cm, 4.44 ± 0.50 g). Six isonitrogenous (40 g 100 g⁻¹) and isoenergetic (17.90 kJ g⁻¹) amino acid test diets were formulated with gradation of 0.1 g 100 g⁻¹ containing graded levels of L-tryptophan (0.04-0.54 g 100 g⁻¹, dry diet). Fish were stocked in triplicate groups, in 75-L circular trough with flow-through system and fed experimental diets at 4% BW/day twice daily. Maximum live weight gain (258%), best feed conversion ratio (FCR) (1.54) and protein efficiency ratio (PER) (1.62) were obtained in fish fed diet containing 0.34 g 100 g⁻¹ tryptophan. However, quadratic regression analysis of weight gain, FCR, PER and body protein deposition (BPD) data indicated requirements for dietary tryptophan at 0.37, 0.33, 0.32 and 0.33 g 100 g⁻¹ of dry diet, respectively. Significantly (P tryptophan diet. Ash content was not significantly different (P > 0.05) among treatments except for diets 0.04 and 0.14 g 100 g⁻¹. Excellent somatic and haematological indices values were obtained at the requirement level. Based on above results, it is recommended that the diet for H. fossilis should contain tryptophan at 0.32 g 100 g⁻¹, dry diet, corresponding to 0.80 g 100 g⁻¹ dietary protein for optimum growth and efficient feed utilization.

  9. Histological characteristic of interrenal and chromaffin cells in relation to ovarian activities in Mystus vittatus (Bloch during growth, maturation, spawning and post-spawning phases

    Directory of Open Access Journals (Sweden)

    Padmanabha Chakrabarti

    2016-09-01

    Full Text Available The histological status of adrenocortical tissues and the correlated seasonal changes in ovarian activities in Mystus vittatus was performed. The tubules and nests of interrenal and chromaffin cells were located in cephalic kidney around the main branches of posterior cardinal vein. Various female germ line cells were identified in the ovary based on size, distinctive features and histoarchitechture of the cells. However, on the basis of relative abundance and size of the different oocytes, the event of oogenesis has been found to occur in four distinct phases, including growth, maturation, spawning and post-spawning. The cytoplasmic features and the architecture of the interrenal and chromaffin cells varied during different phases of the reproductive cycle. During growth and maturation phases, the amount of cytoplasmic granules of interrenal cells increased than chromaffin cells that was in coincidence with the increase of early and late perinucleolar oocytes followed by highest frequency percentage of oocyte at stages IV and V. The cytoplasmic mass of interrenal cells was gradually elevated along with hypertrophied nuclei from the end of maturation and spawning phases also correlated with the increased frequency of mature oocytes. Therefore, gradual accumulation of cytoplasmic granules in the interrenal cells was noticed during post-spawning phase. The cytological variations in the interrenal and chromaffin cells harmonized with constitution of different ovarian cells during different reproductive phase in M. vittatus.

  10. Chronic stress due to high stocking density in open sea cage farming induces variation in biochemical and immunological functions in Asian seabass (Lates calcarifer, Bloch).

    Science.gov (United States)

    Sadhu, Narasimhulu; Sharma, S R Krupesha; Joseph, Shoji; Dube, Praveen; Philipose, K K

    2014-08-01

    Stocking density is an important factor in cage aquaculture of finfish. Effects of high stocking density (35 fish cubic m(-1)) on a range of biochemical and immunological parameters in Asian seabass reared in open sea floating net cages were compared to fish held in relatively low density (15 fish cubic m(-1)). The results revealed that chronic stress due to high stocking density induced variations in most of the parameters studied as evidenced by increased cortisol and glucose levels and decreased activity of lysozyme, myeloperoxidase and complement. Production of reactive oxygen species, total leucocyte count and total serum protein were also decreased, whereas anti-protease, alkaline phosphatase and acid phosphatase activities were increased in high stocking-density group when compared to low stocking-density group. Effects of chronic stress due to high stocking density were discussed in relation to variations in these parameters.

  11. The effect of temperature on the embryonic development of barramundi, the Australian strain of Lates calcarifer (Bloch using current hatchery practices

    Directory of Open Access Journals (Sweden)

    Valentin Thépot

    2015-11-01

    Full Text Available Lates calcarifer (barramundi or Asian seabass has been farmed since the 1970s, yet despite its widespread culture little has been documented on the species’ embryonic development and particularly how development relates to temperature. This is particularly the case for the Australian L. calcarifer genetic strain. Accordingly, embryonic development of fertilised barramundi eggs incubated at 26, 28, 30, 32, 34 and 36 °C were followed from the time of incubation until hatching and the timing to reach key developmental stages and temperature-induced hatching success established. Eggs incubated at 26 and 36 °C did not survive past the first two hours post-fertilisation. Development of the Australian strain of L. calcarifer was observed to proceed similarly to those documented from Asia, however, differences were observed in the timing of major embryonic events among the two strains. Incubation trials showed that eggs maintained at 30 °C had the highest hatch rate (86.7%. The findings of this study are discussed and put in a commercial context with potential future research to further improve practices at the hatchery level.

  12. Effects of hirami lemon, Citrus depressa Hayata, leaf meal in diets on the immune response and disease resistance of juvenile barramundi, Lates calcarifer (bloch), against Aeromonas hydrophila.

    Science.gov (United States)

    Shiu, Ya-Li; Lin, Hsueh-Li; Chi, Chia-Chun; Yeh, Shinn-Pyng; Liu, Chun-Hung

    2016-08-01

    The present study was conducted to evaluate the dietary supplementation of leaf meal from Citrus depressa Hayata on the growth, innate immune response, and disease resistance of juvenile barramundi, Lates calcarifer. Four diets were formulated to contain 0% (control), 1% (C1), 3% (C3), and 5% (C5) leaf meal, respectively. During a 56 d feeding trial, fish survival, growth performance, and feed efficiency were not significantly different among all groups. For immune response, respiratory burst, superoxide dismutase and lysozyme activities were not significantly different among all groups. However, fish fed the C5 diet for 56 d had significantly higher phagocytic activity. Also, fish fed C3 and C5 diets had significantly higher Mx gene expressions in spleens and head kidneys with nerve necrosis virus injections after 24 h. Disease resistance against Aeromonas hydrophila was increased by the C5 diet. In this study, barramundi fed on a diet containing 5% C. depressa Hayata leaf meal had significantly better innate immune response and disease resistance against A. hydrophila. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Diferenciação geográfica de Macrodon ancylodon (Bloch & Schneider, 1801 na costa brasileira, entre as latitudes 18º36'S e 32º10'S: etapa I The geographical differentiation of Macrodon ancylodon (Bloch & Schneider, 1801 in the Brazilian coast between Lat. 18º36'S and 32º10'S: phase I

    Directory of Open Access Journals (Sweden)

    Noriyoshi Yamaguti

    1979-06-01

    Full Text Available Multiple range tests according to Kramer, 1956 were performed on 3 meristic and 15 morphometric characters of "pescada-foguete" (Macrodon ancylodon samples collected off coast near Conceição da Barra (Espirito Santo State, Atafona, Macaé, Ubatuba cities, Bom Abrigo Island and Rio Grande do Sul State coast. It was also observed morphological differences in otoliths collected at each region. The number of statistical differences among samples and different morphological characteristics presented by otoliths suggested the existence of four populations along the studied area: (1 along Espírito Santo State coast; (2 near the region between Atafona and Macaé coasts; (3 along São Paulo, Paraná and north Santa Catarina States coasts and (4 along Rio Grande do Sul State coast. Probably the differentiation was caused by different environmental conditions observed among regions. Other papers about life history corroborate these results except for the Espírito Santo population about which there is no biological information up to the moment.

  14. Introduzione ad "Apologia della storia o Mestiere di storico" / Introduction to “Apologia for History or the Historian’s Craft”

    National Research Council Canada - National Science Library

    Marc Bloch

    2013-01-01

    Si ripubblica qui l’Introduzione ad Apologia della storia o Mestiere di storico di Marc Bloch nella nuova edizione curata dal figlio Etienne Bloch nel 1993 e tradotta per la prima volta in italiano nel 1998...

  15. Análisis morfométrica y merística en sapo lusitánico Halobatrachus didactylus (Bloch and Schneider, 1801): Evidencia de fragmentación poblacional en la costa portuguesa

    OpenAIRE

    José Lino Costa; Pedro Raposo de Almeida; María José Costa

    2003-01-01

    Para investigar la hipótesis de fragmentación de las poblaciones portuguesas de sapo lusitánico Halobatrachus didactylus, se han analizado un total de 207 ejemplares de esta especie, provenientes de seis localidades distintas, a nivel de sus características morfométricas y merísticas. El estudio ha confirmado el aislamiento relativo de las poblaciones del Algarve y de sus homólogas de los estuarios de la costa occidental, demostrando estas últimas, de igual modo, un elevado grado de aislamien...

  16. Cultivo Integral de dos especies de escómbridos: Atún rojo del Atlántico (Thunnus thynnus, L. 1758) y Bonito Atlántico (Sarda sarda, Bloch 1793)

    OpenAIRE

    Ortega-García, A. (Aurelio)

    2015-01-01

    Los escómbridos comprenden una familia de peces pelágicos con un gran potencial para la acuicultura debido a su rápido crecimiento y alto valor comercial. Con la excepción del Atún rojo del pacífico (Thunnus orientalis), especie en la que se ha completado el ciclo vital, la acuicultura integral de las especies pertenecientes a la familia de los escómbridos o es inexistente o se basa en la captura de especímenes adultos. Esta tesis pretende establecer las bases de la reproducción y cultivo lar...

  17. Cultivo integral de dos especies de escómbridos : Atún rojo del Atlántico (Thunnus thynnus, L. 1758) y Bonito Atlántico (Sarda sarda, Bloch 1793)

    OpenAIRE

    Ortega García, Aurelio

    2015-01-01

    Scombridae comprise a family of pelagic fish species with a great potential for aquaculture due to fast growth rates and high commercial values. In the last years, it has been complete the life cycle in captivity of Pacific bluefin tuna (Thunnus orientalis), but with this exception, integral Aquaculture of species belonging to Scombriae does not exist or is capture-based. This thesis pretends to determine the basis for reproduction and larval rearing of two species of scombrids: Atlantic b...

  18. ESTRUCTURA DE LA MACROFAUNA DE INVERTEBRADOS PRESENTE EN LOS NIDOS DEL PEZ MALACANTHUS PLUMIERI (BLOCH, 1786 (PERCIFORMES: MALACANTHIDAE EN LA BAHÍA DE NENGUANGE, PARQUE NACIONAL NATURAL TAYRONA, MAR CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    GUTIÉRREZ-SALCEDO JOSÉ MANUEL

    2007-12-01

    Full Text Available Se realizó la caracterización de la estructura de invertebrados presentes en losmontículos de nidos del pez Malacanthus plumieri durante el segundo semestre de2003, en la bahía de Nenguange, con el fin de establecer diferencias entre dos gruposde nidos diferenciados por su profundidad (5 y 17 m. Se colectaron en total 1760individuos pertenecientes a 152 especies de siete Phyla, la mayoría de las cualesse encuentra asociadas a sustratos rocosos, arrecifes, fondos blandos y cascajo.Por medio de un análisis ecológico multivariado, se estableció la estructura de lacomunidad, además, se calcularon los principales atributos ecológicos tales comoriqueza, abundancia, diversidad, uniformidad y equidad para cada uno de los gruposde nidos establecidos previamente. La caracterización de la comunidad mostró lapresencia de 32 especies generalistas (presentes en los dos grupos de nidos de lascuales Brachycarpus biunguiculatus, Micropanope spinipes y Synalpheus fritzmuelleri tienen una frecuencia relativa superior al 70% cada una. En la franja de los 5 m deprofundidad se colectaron, además de las generalistas, 39 especies características (ej.Mithrax sculptus y Mithrax forceps y 38 especies representadas por un solo individuo.En la franja de los 17 m de profundidad se presentaron 19 especies características(ej. Munida angulata y Petrolisthes galathinus y 24 especies representadas porun solo individuo. Los atributos ecológicos evaluados no mostraron diferenciassignificativas entre las dos franjas batimétricas; el índice de correlación tampocomostró una influencia directa entre el perímetro de los montículos y la estructura dela comunidad

  19. Description of Poecilia (Acanthophacelus) wingei n. sp. from the Paría Peninsula, Venezuela, including notes on Acanthophacelus Eigenmann, 1907 and other subgenera of Poecilia Bloch and Schneider, 1801 (Teleostei, Cyprinodontiformes, Poeciliidae)

    NARCIS (Netherlands)

    Poeser, F.N.; Kempkes, M.; Isbrücker, I.J.H.

    2005-01-01

    The taxonomy of the common guppy, Poecilia reticulata Peters, 1859, is reviewed and the closely related Campoma guppy, P. wingei n. sp., is described. Formerly, the common guppy was not judged to be closely related to any other species of Poecilia, but the new species is the second species to be

  20. The effects of prey size on diet differentiation of seven passerine species at two spring stopover sites

    NARCIS (Netherlands)

    Marchetti, C.M.; Locatelli, D.P.; Van Noordwijk, A.J.; Baldaccini, N.E.

    1998-01-01

    Prey size was evaluated for seven passerine trans-Saharan migrant species at two spring stopover sites in Sardinia, Italy. The species considered were Pied Flycatcher Ficedula hypoleuca, Spotted Flycatcher Muscicapa striata, Redstart Phoenicurus phoenicurus, Garden Warbler Sylvia borin, Whitethroat

  1. Ocean acidification impacts on black sea bass and scup embryos, responses of finfish in laboratory experiments

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Black sea bass (Centropristis striata) and scup (Stenotomus chrysops) compose important recreational and commercial fisheries along the United States Atlantic coast....

  2. Destruction of timber panels by wood boring organisms in Mandovi estuary of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Wagh, A.B.; Anil, A.C.

    Destruction on mango wood (Mangifera indica Linn.) panels in the Mandovi Estuary of Goa, India at 5 different depths was studied for different seasons. The causative organisms were found to be Lyrodus pedicellatus Quatrefages and Martesia striata L...

  3. Inhibition of Pro-inflammatory Cytokines by Ethyl Acetate Extract of ...

    African Journals Online (AJOL)

    inflammatory production by macrophages. Methods: Mouse peritoneal macrophages were cultured in solvent either alone or with 2 ìg/ml lipopolysaccaride (LPS) with/without different doses of ethyl acetate extract of S. striata. Production of ...

  4. Synthesis and biological evaluation of the binding of dopamine D2/D3 receptor agonist, (R,S)-5-hydroxy-2-(N-propyl-N-5'-{sup 18}F-fluoropentyl)aminotetralin ({sup 18}F-5-OH-FPPAT) in rodents and nonhuman primates

    Energy Technology Data Exchange (ETDEWEB)

    Shi Bingzhi; Narayanan, Tanjore K.; Christian, Bradley T.; Chattopadhyay, Sankha; Mukherjee, Jogeshwar E-mail: mukherjj@uci.edu

    2004-04-01

    We have synthesized a new fluorinated dopamine D2 receptor agonist, (R,S)-2-(N-propyl-N-5'-fluoropentyl)amino-5-hydroxytetralin (5-OH-FPPAT). The radiosynthesis of the fluorine-18 analog, {sup 18}F-5-OH-FPPAT was achieved in decay corrected yields of 10 to 15% in specific activities of approx. 1.5 to 2 Ci/{mu}mol. In vitro binding and autoradiographic studies of this new radiotracer have been investigated. Using rat striatal homogenate binding assay, 5-OH-FPPAT exhibited an affinity of IC{sub 50} = 6.95 nM. The octanol-buffer partition coefficient, Log P was found to be 1.60. In vitro autoradiographs in rat brain slices with {sup 18}F-5-OH-FPPAT revealed selective binding to the dopaminergic regions in the striata that was displaceable by sulpiride. This selective binding to the striata was also removed in the presence of the GTP analog, 5'-guanylylimidodiphosphate, indicative of predominant binding of {sup 18}F-5-OH-FPPAT to the high-affinity state of the D2 receptor. In vivo regional distribution of {sup 18}F-5-OH-FPPAT in rat brains revealed selective localization in the striata with striata/cortex ratio of 1.5 and striata/cerebellum ratio of 1.8 to 2.0. The binding of {sup 18}F-5-OH-FPPAT in the striata was reduced upon pretreatment with the antagonist, risperidone and the agonist, PPHT. A PET study in rhesus monkeys showed selective localization of {sup 18}F-5-OH-FPPAT in the striata and the ratio between striata and cerebellum approached approximately 2 at 40 min post-injection. Keywords: {sup 18}F-5-OH-FPPAT; Dopamine D-2 Receptor Agonist; In vitro Autoradiography; PET.

  5. Abundances and Habitat Sensitivities of Some River Fishes in ...

    African Journals Online (AJOL)

    Abundances were largest for Channa gachua, Dermogenys pusillus and Mastacembelus armatus but for none of the 18 species were they large relative to the total numbers of fish captured. The importance of habitat characteristics to abundance was examined by multiple regression analysis for those species captured at ...

  6. Isolation, identification and characterization of Leuconostoc ...

    African Journals Online (AJOL)

    The intestinal microflora of snakehead (Channa striatus) fish was studied to isolate and identify lactic acid bacteria as new probiotic. A total of five lactic acid bacteria were isolated from intestine to evaluate with probiotic properties. Leuconostoc mesenteroides sp. mesenteroides with more ability to inhibit growth of ...

  7. Download this PDF file

    African Journals Online (AJOL)

    O.R.S.T.O.M Ser. Hydrobiol. S. (2), 113 - 36. Ekpo, A. E. (1993). Growth, Feeding and Reproductive biology of Hydrocynus forskalii, Alestes macrolepidotus and Channa obscura in. Asefire reservoir, Nigeria. Ph.D. Thesis, University of Ibadan,. Ibadan. Fasedimi, B.T. (1984). The biology of Alestes macrolepidotus from Asire ...

  8. Browse Title Index

    African Journals Online (AJOL)

    Items 9901 - 9950 of 11090 ... CR Devgoswami, MC Kalita, J Talukdar, R Bora, P Sharma. Vol 10, No 12 (2011), Studies on the immature stages and burrow excavating behavior of Schizodactylus monstrosus (Drury) (Grylloptera: Gryllodea: Schizodactylidae) from Sindh, Pakistan, Abstract PDF. SA Channa, R Sultana, MS ...

  9. Author Details

    African Journals Online (AJOL)

    Adedire, O. Vol 2, No 2 (2005) - Articles Digestive Enzyme Assays In The Gut Of Oreochromis Niloticus Linnaeus 1757, Parachanna (Channa) Obscura Gunther 1861 And Gymnarchus Niloticus Cuvier 1829. Abstract. ISSN: 1597-3115. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians ...

  10. A Ramachandran

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana. A Ramachandran. Articles written in Sadhana. Volume 33 Issue 5 October 2008 pp 615-628. Minimization and identification of conducted emission bearing current in variable speed induction motor drives using PWM inverter · A Ramachandran M Channa Reddy Ranjan Moodithaya · More Details ...

  11. Family crisis intervention

    NARCIS (Netherlands)

    Al, C.M.W.

    2012-01-01

    Als een gezin in crisis is, is er hulp nodig. De balans is dan zo verstoord dat een onveilige situatie voor kinderen kan ontstaan. Maar heeft de hulp die deze gezinnen krijgen wel het gewenste resultaat? Channa Al analyseerde 20 evaluatiestudies en toont aan dat intensieve hulpverleningsprogramma’s

  12. Fungal infection in freshwater fishes of Andhra Pradesh, India

    African Journals Online (AJOL)

    Biotechnology

    2015-02-11

    Feb 11, 2015 ... A total of 17 isolates of fungi were isolated from diseased fishes which belong to five species namely. Saprolegnia diclina, Saprolegnia ferax, Saprolegnia hypogyana, Saprolegnia parasitica and Achlya americana. All these fungi were isolated from six different species of fresh water fishes viz. Channa.

  13. Wave propagation in structured materials as a platform for effective parameters retrieving

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Ha, S.; Sukhorukov, A. A.

    utilization of the Bloch-mode analysis5. The idea is to perform the Bloch mode expansion6 of the field inside the metamaterial slab when it is illuminated with a plane wave incident from vacuum. Then we determine the effective refractive index from the propagation constant of the dominating (fundamental......) Bloch mode. The Bloch and wave impedances are determined by definition as the proportionality coefficient between electric and magnetic fields of the fundamental Bloch mode volume or surface averaged over the unit cell1. The ratio of the surface averaged fields provides the value of the Bloch impedance...... and, respectively, enables the retrieval of wave EPs. The volume averaging provides the wave impedance, which is needed for the retrieval of the materials parameters. The main advantage of our method is its simple numerical realization. The first part of the method involves the extraction...

  14. Browse Author Index - African Journals Online

    African Journals Online (AJOL)

    Bloch, C.E. · Bloch, E.M. · Bloch, J.M. · Block, B · Blockman, M · Blockman, Marc · Blockman, Marc · Blom, D J · Blom, D J · Blom, MW · Bloom, Peter D · Blumberg, L · Blumberg, LH · Blumberg, Lucille · Blumenthal, N. J. · Blumenthal, R · Blumenthal, Ryan 401 - 450 of 740 Items >>. ISSN: 0256- ...

  15. Arbuscular mycorrhizal fungi facilitate the invasion of Solidago canadensis L. in southeastern China

    Science.gov (United States)

    Yang, Ruyi; Zhou, Gang; Zan, Shuting; Guo, Fuyu; Su, Nannan; Li, Jing

    2014-11-01

    The significance of arbuscular mycorrhizal fungi (AMF) in the process of plant invasion is still poorly understood. We hypothesize that invasive plants would change local AMF community structure in a way that would benefit themselves but confer less advantages to native plants, thus influencing the extent of plant interactions. An AMF spore community composed of five morphospecies of Glomus with equal density (initial AMF spore community, I-AMF) was constructed to test this hypothesis. The results showed that the invasive species, Solidago canadensis, significantly increased the relative abundance of G. geosperum and G. etunicatum (altered AMF spore community, A-AMF) compared to G. mosseae, which was a dominant morphospecies in the monoculture of native Kummerowia striata. The shift in AMF spore community composition driven by S. canadensis generated functional variation between I-AMF and A-AMF communities. For example, I-AMF increased biomass and nutrient uptake of K. striata in both monocultures and mixtures of K. striata and S. canadensis compared to A-AMF. In contrast, A-AMF significantly enhanced root nitrogen (N) acquisition of S. canadensis grown in mixture. Moreover, mycorrhizal-mediated 15N uptake provided direct evidence that I-AMF and A-AMF differed in their affinities with native and invading species. The non-significant effect of A-AMF on K. striata did not result from allelopathy as root exudates of S. canadensis exhibited positive effects on seed germination and biomass of K. striata under naturally occurring concentrations. When considered together, we found that A-AMF facilitated the invasion of S. canadensis through decreasing competitiveness of the native plant K. striata. The results supported our hypothesis and can be used to improve our understanding of an ecosystem-based perspective towards exotic plant invasion.

  16. The Fundamental Group and Extensions of Motives of Jacobians of ...

    Indian Academy of Sciences (India)

    57

    2016-09-07

    Sep 7, 2016 ... [Blo84] Spencer Bloch. Algebraic cycles and values of L-functions. J. Reine Angew. Math., 350:94–108, 1984. [Blo00] Spencer J. Bloch. Higher regulators, algebraic K-theory, and zeta functions of elliptic curves, vol- ume 11 of CRM Monograph Series. American Mathematical Society, Providence, RI, 2000.

  17. From lanosterol to cholesterol: Structural evolution and differential effects on lipid bilayers

    DEFF Research Database (Denmark)

    Miao, Ling; Nielsen, Morten; Thewalt, J.

    2002-01-01

    Cholesterol is an important molecular component of the plasma membranes of mammalian cells. Its precursor in the sterol biosynthetic pathway, lanosterol, has been argued by Konrad Bloch (Bloch, K. 1965. Science. 150:19-28; 1983. CRC Crit Rev. Biochem. 14:47-92; 1994. Blonds in Venetian Paintings...

  18. Juudi naise pilt purustas hinnarekordi / Eda Post

    Index Scriptorium Estoniae

    Post, Eda, 1983-

    2006-01-01

    Miljardär Roland Lauderile kuuluv New Yorgi saksa ja austria kunsti muuseum Neue Galerie ostis 135 miljoni dollari eest austria kunstniku Gustav Klimti õlimaali "Kuldne Adele" Adele Bloch-Bauerist. Lähemalt maali valmimisest ja saatusest. Bloch-Baueri kunstikogu saatusest

  19. Properties of superposition operators acting between Bμ∗ and QK∗

    Directory of Open Access Journals (Sweden)

    Alaa Kamal

    2015-10-01

    Full Text Available In this paper we introduce natural metrics in the hyperbolic Bloch and QK-type spaces with respect to which these spaces are complete. Moreover, Lipschitz continuous, bounded and compact superposition operators Sϕ from the hyperbolic Bloch type space to the hyperbolic QK-type space are characterized by conditions depending only on the analytic symbol ϕ.

  20. Evaluation of butachlor for control of some submerged macrophytes along with its impact on biotic components of freshwater system

    Directory of Open Access Journals (Sweden)

    A. Chattopadhyay, S. Adhikari, S. P. Adhikary, S. Ayyappan

    2006-04-01

    Full Text Available In this investigation, the efficacy of the herbicide butachlor, (N-butoxymethyl-2 chloro-21, 61 diethyl acetanilide was tested against few common submerged macrophytes namely Hydrilla (Hydrilla verticillata (L. Royale, Najas (Najas minor All., Nechamandra (Nechamandra alternifolia (Roxb. Thwaites and Ottelia (Ottelia alismoides (L. Pers. of freshwater fish ponds. Almost complete decay of Hydrilla, Nechamandra and Ottelia was achieved at 7.5 L of active ingredient/ha/m butachlor within 15 days while the herbicide showed no negative effect on Najas. However at the same concentration of butachlor, total mortality of zooplankton and water fern Azolla (Azolla caroliniana Lamarck occurred within seven days. In case of few freshwater fish species like Rohu (Labeo rohita, Channa (Channa punctatus, Anabas (Anabas testitudineus and Heteropneustes (Heteropneustes fossilis, total mortality occurred upto 90 days after application of the same dose of butachlor but fish survived beyond 120 days of herbicide application indicating degradation of the herbicides.

  1. Fish diversity and assemblage structure in Ken River of Panna landscape, central India

    OpenAIRE

    Johnson, J.A.; Parmar, R.; Ramesh, K; S Sen; R.S. Murthy

    2012-01-01

    Fish diversity and assemblage structure in relation to habitat variables were studied in 15 sites in Panna landscape, central India. The sampling was performed between February-April 2009. Fifty species of fishes belonging to 32 genera, 15 families and four orders were recorded from the study area. Cyprinids were the dominant assemblage members in all study streams (abundance ranges from 56.6-94.5 %). The cyprinid Devario aequipinnatus and the snakehead Channa gachua had highest local dom...

  2. Uso de biomarcador histopatológico em brânquias de Centropomus undecimalis (Bloch, 1972 na avaliação da qualidade da água do Parque Ecológico Laguna da Jansen, São Luís - MA

    Directory of Open Access Journals (Sweden)

    S.M. Cantanhêde

    2014-04-01

    Full Text Available Com o objetivo de analisar a intensidade das alterações histológicas em brânquias de Centropomus undecimalis para avaliar a qualidade da água do Parque Ecológico Laguna da Jansen, em São Luís, Estado do Maranhão, coletaram-se exemplares de peixes no período chuvoso de 2012 e amostras de água nos períodos seco de 2011 e chuvoso de 2012 para análises físico-química e bacteriológica. Os resultados mostraram que a maioria dos parâmetros físico-químicos e bacteriológicos estava de acordo com os valores estabelecidos pela Resolução do CONAMA nº 357 de 2005. As alterações histológicas observadas foram: elevação do epitélio lamelar; proliferação excessiva de células dos epitélios filamentar e lamelar causando fusão total ou parcial das lamelas; alteração da estrutura das lamelas; hiperplasia das células mucosas; ruptura do epitélio lamelar; espessamento descontrolado do tecido proliferativo filamentar e lamelar e aneurismas de vários tamanhos. Também foi observada a presença de parasito em alguns exemplares. O Índice de Alteração Histológica (IAH por indivíduo variou de 2 a 114. O valor médio do IAH obtido foi de 40,3, demonstrando que as brânquias dos indivíduos amostrados da espécie C. undecimalis apresentaram alterações de moderadas para severas no tecido. As alterações histológicas encontradas indicam que esses indivíduos desenvolveram mecanismos de defesa contra a ação de estressores presentes na água da laguna e a um provável desequilíbrio parasito-hospedeiro-ambiente associado à baixa qualidade do ambiente.

  3. Transverse Leukonychia: A case report

    African Journals Online (AJOL)

    authors emphasize that white transverse nail banding —. Leukonychia striata or Muehrcke lines - constitute an aesthetical unpleasant side-effect of medication, but may represent an easily observed sign indicative of previous use of cytotoxic therapy for malignancy. Key-words: Chemotherapy-induced nail changes,.

  4. Simulating effects of brain atrophy in longitudinal PET imaging with an anthropomorphic brain phantom

    DEFF Research Database (Denmark)

    Jonasson, L S; Axelsson, J; Riklund, K

    2017-01-01

    cameras and reconstruction algorithms. Here, a 3D-printed anthropomorphic brain phantom with attachable striata in three sizes was designed to enable controlled volumetric changes. Using a method to eliminate the non-radioactive plastic wall, and manipulating BP levels by adding different number of events...

  5. Linaria repens (L.) Mill. x L. vulgaris Mill

    NARCIS (Netherlands)

    Ooststroom, van S.J.; Reichgelt, Th.J.

    1958-01-01

    Linaria repens (L.) Mill. (L. monspessulana (L.) Mill.; L. striata Lamk. & DC.) is bij ons reeds meermalen als adventief gevonden en blijkt zich op enkele plaatsen te handhaven. Dit laatste is bv. het geval te Arnhem, aan de Koningsweg. De soort werd daar in 1952 aangetroffen door Dr. A.G. de Wilde

  6. Dicty_cDB: SSD735 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available .41 2 AF265481 |AF265481.1 Restrepia aristulifera trnK gene, intron sequence; and maturase (matK) gene, comp...es for chloroplast products. 42 0.42 2 AF265480 |AF265480.1 Restrepiopsis striata trnK gene, intron sequence

  7. Pathology of worm infestation in ovine and its treatment with two ...

    African Journals Online (AJOL)

    Villi were broad and appeared to be flattened in distal regions of small intestine of infected animal in comparison to treated group of the lambs after eight weeks with the plant extraction of S. striata. Significant changes were observed in protein fractions. Significant increases in body weight were also observed in infected ...

  8. Dicty_cDB: Contig-U11461-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available hymomyza amoena voucher 107543 16S ribosomal RNA... 36 2.6 2 ( EU494468 ) Drosophila mediodiffusa voucher 10... ribosoma... 36 2.6 2 ( EU494517 ) Drosophila ochracea voucher 109447 16S ribosomal ... 36 2.6 2 ( EU494470 ) Drosophila medio...striata voucher 109394 16S riboso... 36 2.6 2 ( EU494469 ) Drosophila mediopictoides vouch

  9. Inhibition of Pro-inflammatory Cytokines by Ethyl Acetate Extract of ...

    African Journals Online (AJOL)

    Inhibition of Pro-inflammatory Cytokines by Ethyl. Acetate Extract of Scrophularia striata. Abbas Azadmehr1, Ghorban Maliji2*, Reza Hajiaghaee3, Mojtaba. Shahnazi4 and Ahmad Afaghi5. 1Immunology Department, Qazvin University of Medical Sciences, Qazvin, 2Immunology Department, Babol. University of Medical ...

  10. High-Q submicron-diameter quantum-dot microcavity pillars for cavity QED experiments

    DEFF Research Database (Denmark)

    Gregersen, Niels; Lermer, Matthias; Dunzer, Florian

    and allowing for a single localized mode inside the cavity. The fundamental Bloch mode experiences an adiabatic transition, leading to an improved mode matching and a reduced coupling to propagating Bloch modes in the DBRs. The central GaAs layer incorporating quantum dots is only 60 nm thick corresponding...... to ≈ λ/5, and regular cavity concepts are thus insufficient to explain the localization of the cavity mode, demonstrating the necessity of Bloch-wave formalism in the analysis of the design. We compare our adiabatic design to a reference incorporating a λ-spacer. A theoretical improvement of Q of two...

  11. The effects of next-to-nearest-neighbour hopping on Bose–Einstein ...

    Indian Academy of Sciences (India)

    - to-nearest-neighbour boson hopping (t ) energy on Bose–Einstein condensation in cubic lattices. We consider both non-interacting and repulsively interacting bosons moving in the lowest Bloch band. The interacting bosons are studied using ...

  12. Croissance et âge des poissons capitaines: Polydactylus quadrifilis ...

    African Journals Online (AJOL)

    Croissance et âge des poissons capitaines: Polydactylus quadrifilis (Cuvier, 1829), Galeoides decadactylus (Bloch, 1795) et Pentanemus quinquarius (Linné, 1758) de la pêcherie artisanale maritime de Grand-Lahou (Côte d'Ivoire)

  13. Wave propagation in metamaterials and effective parameters retrieving

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Ha, S.; Sukhorukov, A.

    2011-01-01

    as handsome for implementation. We set a goal to develop a method which is unambiguous but at the same time simple and straightforward. We assume that this can be done by observing the wave propagation inside a metamaterial slab thick enough to avoid transient effects. First, we formulated a retrieval method...... with a plane wave incident from vacuum. Then we determine the effective refractive index from the propagation constant of the dominating (fundamental) Bloch mode. The Bloch and wave impedances are determined by definition as the proportionality coefficient between the electric and magnetic fields...... complex wave effective parameters. Extending the method further we developed the approach to determine both wave and material effective parameters through the Bloch-mode analysis [3]. The idea is to perform the Bloch mode expansion [4] of the field inside the metamaterial slab when it is illuminated...

  14. Wide-angle beam splitting by use of positive-negative refraction in photonic crystals.

    Science.gov (United States)

    Luo, Ye; Zhang, Wei; Huang, Yidong; Zhao, Jianhui; Peng, Jiangde

    2004-12-15

    We present a positive-negative refraction effect in which, under certain conditions, an incident plane wave launched into a photonic crystal excites a positive-refracted Bloch wave and a negative-refracted Bloch wave simultaneously, both of which maintain the polarization. By utilizing this phenomenon, wide-angle beam splitting can be realized at the microscale level. Numerical simulations are employed to demonstrate this anomalous refraction behavior.

  15. H.E. Mr Leonid A. Skotnikov, Ambassador, Permanent Representative of the Russian Federation to the United Nations and other International Organisations in Geneva

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Photo 01: H.E. Mr Leonid A. Skotnikov, Ambassador of the Russian Federation to the United Nations and other International Organisations in Geneva (centre) with (from left to right) V. Kaftanov, Ph. Bloch, N. Koulberg, F. Grishaev Photo 02: H.E. Mr Leonid A. Skotnikov, Ambassador of the Russian Federation to the United Nations and other International Organisations in Geneva (centre) with Ph. Bloch (behind the Ambassador, V. Kaftanov) visiting the crystal laboratory in building 27.

  16. The Laughter as Hope Principle

    Directory of Open Access Journals (Sweden)

    Mateus Domingues da Silva

    2015-04-01

    Full Text Available The work aims to establish a parallel between the concept of laughter and the Hope Principle of Ernst Bloch, differentiating their relationship between the pursuit of individual happiness, said to be ideological, deceptive and precarious, and the pursuit of collective happiness, altruistic, that despite utopian it is also true and real, just for being selfless and real because, as a collective expression, indicating concretely and politically, is a real possibility.Keywords: Laughter, Hope Principle, Ernest Bloch, altruism.

  17. Weighted composition operators from Bergman-type spaces into ...

    Indian Academy of Sciences (India)

    Abstract. Let ϕ be an analytic self-map and u be a fixed analytic function on the open unit disk D in the complex plane C. The weighted composition operator is defined by. uCϕf = u · (f ◦ ϕ), f ∈ H(D). Weighted composition operators from Bergman-type spaces into Bloch spaces and little. Bloch spaces are characterized by ...

  18. Klimti tööd tagasi saanud juudi pere müüb need maha

    Index Scriptorium Estoniae

    2006-01-01

    Klimti maalide "Kasemets/Pöögimets" (1901), "Adele Bloch-Bauer II" (1912), "Õunapuu" (1912) ja "Majad Unterachis Attersee ääres" (1916) õiguspäraseks omanikuks tunnistati Ferdinand Bloch-Baueri vennatütar Maria Altmann. Maalid müüakse sügisel. Praegu asuvad maalid New Yorgis saksa ja austria kunsti muuseumis Neue Galerie's

  19. Taxonomical notes on selected freshwater fish species described from northern and central Vietnam (Cypriniformes: Balitoridae, Cobitidae, Cyprinidae, Nemacheilidae; Perciformes: Channidae, Osphronemidae; Synbranchiformes: Mastacembelidae).

    Science.gov (United States)

    Endruweit, Marco

    2014-03-01

    Selected, little known taxa of northern and central Vietnamese freshwater fish species are reviewed. Nomenclatural acts are taken: Hemibarbus lehoai is placed in synonymy of H. maculatus, Paracobitis hagiangensis in synonymy of Schistura caudofurca. A neotype of Micronemacheilus bacmeensis is assigned. The name Channa hanamensis is treated as a nomen nudum. Two labeonine species described from China are nomenclaturally affected: Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition; the specific epithet of Sinigarra napoense is corrected to napoensis.

  20. Taxonomical notes on selected freshwater fish species described from northern and central Vietnam (Cypriniformes: Balitoridae, Cobitidae, Cyprinidae, Nemacheilidae; Perciformes: Channidae, Osphronemidae; Synbranchiformes: Mastacembelidae)

    Science.gov (United States)

    Endruweit, Marco

    2014-01-01

    Selected, little known taxa of northern and central Vietnamese freshwater fish species are reviewed. Nomenclatural acts are taken: Hemibarbus lehoai is placed in synonymy of H. maculatus, Paracobitis hagiangensis in synonymy of Schistura caudofurca. A neotype of Micronemacheilusbacmeensis is assigned. The name Channa hanamensis is treated as a nomen nudum. Two labeonine species described from China are nomenclaturally affected: Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition; the specific epithet of Sinigarra napoense is corrected to napoensis. PMID:24668657

  1. Dynamique du peuplement des Oiseaux d'une riziculture et ses ...

    African Journals Online (AJOL)

    SARAH

    31 juil. 2014 ... 4. 0. Ac. Phylloscopus sibilatrix (Bechstein, 1793). P. F. Hylia prasina (Cassin, 1855) A05. R. F. 12 10 10. 9. 6. 8. 11 12. 9. 9 13 11 13. 10 ± 1,95. 120 0,07 Ac. Muscicapidae. Muscicapa striata (Pallas, 1764). P f. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 2. 0. 2. 0,17 ± 0,58. 2. 0. Ac. Muscicapa cassini Heine, 1860 A05. R. F. 1.

  2. Comparative leaf anatomy in argentine Galactia species Anatomía comparada de hoja en especies argentinas de Galactia

    OpenAIRE

    G. M. Tourn; M. T. Cosa; G. G. Roitman; SILVA, M. P.

    2009-01-01

    A comparative study of anatomical characters of the leaves of argentine species of Genera Galactia was carried out in order to evaluate their potential value in Taxonomy. In Argentine 14 species and some varieties from Sections Odonia and Collaearia can be found. Section Odonia: G. benthamiana Mich., G. dubia DC., G. fiebrigiana Burkart var. correntina Burkart, G. glaucophylla Harms, G. gracillima Benth., G. latisiliqua Desv., G. longifolia (Jacq.) Benth., G. marginalis Benth., G. striata (Ja...

  3. Positive feedback between mycorrhizal fungi and plants influences plant invasion success and resistance to invasion.

    Directory of Open Access Journals (Sweden)

    Qian Zhang

    Full Text Available Negative or positive feedback between arbuscular mycorrhizal fungi (AMF and host plants can contribute to plant species interactions, but how this feedback affects plant invasion or resistance to invasion is not well known. Here we tested how alterations in AMF community induced by an invasive plant species generate feedback to the invasive plant itself and affect subsequent interactions between the invasive species and its native neighbors. We first examined the effects of the invasive forb Solidago canadensis L. on AMF communities comprising five different AMF species. We then examined the effects of the altered AMF community on mutualisms formed with the native legume forb species Kummerowia striata (Thunb. Schindl. and on the interaction between the invasive and native plants. The host preferences of the five AMF were also assessed to test whether the AMF form preferred mutualistic relations with the invasive and/or the native species. We found that S. canadensis altered AMF spore composition by increasing one AMF species (Glomus geosporum while reducing Glomus mosseae, which is the dominant species in the field. The host preference test showed that S. canadensis had promoted the abundance of AMF species (G. geosporum that most promoted its own growth. As a consequence, the altered AMF community enhanced the competitiveness of invasive S. canadensis at the expense of K. striata. Our results demonstrate that the invasive S. canadensis alters soil AMF community composition because of fungal-host preference. This change in the composition of the AMF community generates positive feedback to the invasive S. canadensis itself and decreases AM associations with native K. striata, thereby making the native K. striata less dominant.

  4. Development of Solar Drying Model for Selected Cambodian Fish Species

    Directory of Open Access Journals (Sweden)

    Anna Hubackova

    2014-01-01

    Full Text Available A solar drying was investigated as one of perspective techniques for fish processing in Cambodia. The solar drying was compared to conventional drying in electric oven. Five typical Cambodian fish species were selected for this study. Mean solar drying temperature and drying air relative humidity were 55.6°C and 19.9%, respectively. The overall solar dryer efficiency was 12.37%, which is typical for natural convection solar dryers. An average evaporative capacity of solar dryer was 0.049 kg·h−1. Based on coefficient of determination (R2, chi-square (χ2 test, and root-mean-square error (RMSE, the most suitable models describing natural convection solar drying kinetics were Logarithmic model, Diffusion approximate model, and Two-term model for climbing perch and Nile tilapia, swamp eel and walking catfish and Channa fish, respectively. In case of electric oven drying, the Modified Page 1 model shows the best results for all investigated fish species except Channa fish where the two-term model is the best one. Sensory evaluation shows that most preferable fish is climbing perch, followed by Nile tilapia and walking catfish. This study brings new knowledge about drying kinetics of fresh water fish species in Cambodia and confirms the solar drying as acceptable technology for fish processing.

  5. Fatty acid and amino acid composition in haruan as a potential role in wound healing.

    Science.gov (United States)

    Jais, A M; McCulloch, R; Croft, K

    1994-09-01

    1. Two species of snakehead fish are available in Sabah, i.e. Channa striatus and Channa melanosoma, and are commonly known as haruan. Haruan is consumed by many Malaysians to induce healing after a clinical operations. However, there is no scientific evidence as yet to substantiate the claim, and so it was decided to analyse the biochemical composition in haruan to determine which compounds may have a possible role or potential in wound healing. 2. Samples (midline fillet) of both species were extracted separately in hexane for the qualitative analysis of fatty acids by a gas chromatography, Hewlett-Packard 5890A, using a 10 meter superox 11 column (Alltech) at temperature between 190 and 245 degrees C. Peak areas were calculated automatically using Hewlett-Packard 3393A computing integrator. Subsequently, the amino acid composition was analysed using a precolumn derivatization reverse phase HPLC waters PICO-TAG system. 3. Haruan is found to contain unusually high arachidonic acid (AA) but almost no eicosapentaenoic acid (EPA). AA which is a precursor of prostaglandin may initiate blood clotting and be responsible for growth. Haruan also contains all the essential amino acids for wound healing, particularly glycine which is the most important component of human skin collagen. Therefore, haruan contained all the basic biochemical requirements for wound healing.

  6. Development of solar drying model for selected Cambodian fish species.

    Science.gov (United States)

    Hubackova, Anna; Kucerova, Iva; Chrun, Rithy; Chaloupkova, Petra; Banout, Jan

    2014-01-01

    A solar drying was investigated as one of perspective techniques for fish processing in Cambodia. The solar drying was compared to conventional drying in electric oven. Five typical Cambodian fish species were selected for this study. Mean solar drying temperature and drying air relative humidity were 55.6 °C and 19.9%, respectively. The overall solar dryer efficiency was 12.37%, which is typical for natural convection solar dryers. An average evaporative capacity of solar dryer was 0.049 kg · h(-1). Based on coefficient of determination (R(2)), chi-square (χ(2)) test, and root-mean-square error (RMSE), the most suitable models describing natural convection solar drying kinetics were Logarithmic model, Diffusion approximate model, and Two-term model for climbing perch and Nile tilapia, swamp eel and walking catfish and Channa fish, respectively. In case of electric oven drying, the Modified Page 1 model shows the best results for all investigated fish species except Channa fish where the two-term model is the best one. Sensory evaluation shows that most preferable fish is climbing perch, followed by Nile tilapia and walking catfish. This study brings new knowledge about drying kinetics of fresh water fish species in Cambodia and confirms the solar drying as acceptable technology for fish processing.

  7. Genomic Organization of Repetitive DNA Elements and Its Implications for the Chromosomal Evolution of Channid Fishes (Actinopterygii, Perciformes)

    Science.gov (United States)

    Cioffi, Marcelo de Bello; Bertollo, Luiz Antonio Carlos; Villa, Mateo Andres; de Oliveira, Ezequiel Aguiar; Tanomtong, Alongklod; Yano, Cassia Fernanda; Supiwong, Weerayuth; Chaveerach, Arunrat

    2015-01-01

    Channid fishes, commonly referred to as “snakeheads”, are currently very important in Asian fishery and aquaculture due to the substantial decline in natural populations because of overexploitation. A large degree of chromosomal variation has been found in this family, mainly through the use of conventional cytogenetic investigations. In this study, we analyzed the karyotype structure and the distribution of 7 repetitive DNA sequences in several Channa species from different Thailand river basins. The aim of this study was to investigate the chromosomal differentiation among species and populations to improve upon the knowledge of its biodiversity and evolutionary history. Rearrangements, such as pericentric inversions, fusions and polyploidization, appear to be important events during the karyotypic evolution of this genus, resulting in the chromosomal diversity observed among the distinct species and even among populations of the same species. In addition, such variability is also increased by the genomic dynamism of repetitive elements, particularly by the differential distribution and accumulation of rDNA sequences on chromosomes. This marked diversity is likely linked to the lifestyle of the snakehead fishes and their population fragmentation, as already identified for other fish species. The karyotypic features highlight the biodiversity of the channid fishes and justify a taxonomic revision of the genus Channa, as well as of the Channidae family as a whole, as some nominal species may actually constitute species complexes. PMID:26067030

  8. Ferroelectricity of domain walls in rare earth iron garnet films.

    Science.gov (United States)

    Popov, A I; Zvezdin, K A; Gareeva, Z V; Mazhitova, F A; Vakhitov, R M; Yumaguzin, A R; Zvezdin, A K

    2016-11-16

    In this paper, we report on electric polarization arising in a vicinity of Bloch-like domain walls in rare-earth iron garnet films. The domain walls generate an intrinsic magnetic field that breaks an antiferroelectric structure formed in the garnets due to an exchange interaction between rare earth and iron sublattices. We explore 180° domain walls whose formation is energetically preferable in the films with perpendicular magnetic anisotropy. Magnetic and electric structures of the 180° quasi-Bloch domain walls have been simulated at various relations between system parameters. Singlet, doublet ground states of rare earth ions and strongly anisotropic rare earth Ising ions have been considered. Our results show that electric polarization appears in rare earth garnet films at Bloch domain walls, and the maximum of magnetic inhomogeneity is not always linked to the maximum of electric polarization. A number of factors including the temperature, the state of the rare earth ion and the type of a wall influence magnetically induced electric polarization. We show that the value of polarization can be enhanced by the shrinking of the Bloch domain wall width, decreasing the temperature, and increasing the deviations of magnetization from the Bloch rotation that are regulated by impacts given by magnetic anisotropies of the films.

  9. Mechanisms for the symmetric and antisymmetric switching of a magnetic vortex core: Differences and common aspects

    Science.gov (United States)

    Noske, Matthias; Stoll, Hermann; Fähnle, Manfred; Hertel, Riccardo; Schütz, Gisela

    2015-01-01

    Three-dimensional micromagnetic simulations of the switching of a magnetic vortex core in a cylindrical nanodisk are performed, for excitations with out-of-plane fields (symmetric switching) or with various types of time-dependent in-plane fields (asymmetric switching). Although the switching mechanisms are different in detail, all switching events must involve the movement of a Bloch point through the disk, because the switching leads to a change of the Skyrmion number which is a topological invariant as long as there is no action of a Bloch point. The momentary magnetization configurations are different in different layers of the disk. Because of the three-dimensionality it is often difficult to decide whether the asymmetric switching is caused by the splitting of the dip close to the vortex core into a vortex-antivortex pair, and the annihilation of the original vortex with the antivortex (whereby a Bloch point moves). It is suggested that there are situations for which such a switching occurs by the formation of a Bloch point in a configuration which is already similar to a vortex-antivortex configuration, but by a movement of this Bloch point before the formation of a complete pair and without the annihilation of the original vortex with an antivortex.

  10. Terahertz Luminescence and Electrical Characteristics of SiC Structures with Natural Superlattice in Strong Electric Fields

    Science.gov (United States)

    Sankin, V. I.; Andrianov, A. V.; Petrov, A. G.; Zakhar'in, A. O.; Nagalyuk, S. S.; Shkrebiy, P. P.

    2017-12-01

    Recently, the intense terahertz electroluminescence from monopolar n++-n--n+ structures of 8H-SiC natural superlattice at helium temperatures due to Bloch oscillations was found out. In the present work, we compare the THz emission and electrical characteristics of monopolar n++-n--n+ and bipolar n++- π-n+ 8H-SiC structures at 7 K. The bipolar n++- π-n+ 8H-SiC structures were analogous to those on which the negative differential conductivity effect was observed earlier for three polytypes (4H, 6H, and 8H) at T = 300 K. The obtained results allow one to draw a conclusion about common nature of the negative differential conductivity and THz emission effects in the natural superlattice of SiC caused by Bloch oscillations. These results give the proof of fundamental importance supporting the objectivity of postulates of the F. Bloch - C. Zener - G. N. Wannier theory

  11. The effect of thermal fluctuations on Holstein polaron dynamics in electric field

    Science.gov (United States)

    Voulgarakis, Nikolaos K.

    2017-08-01

    In this work, we have studied the effects of thermal fluctuations on the stability of polaron motion under the influence of an external electric field. Zero temperature calculations have been reported previously showing the existence of critical electric field, Ecr, where the system transitions from a stable polaron motion to a Bloch-like oscillation. In this study, we further report that for intermediate polaron sizes the lifetime of such Bloch-like oscillations decay with time due to excessive phonon emission. Our numerical simulations show that the value of Ecr is finite for small temperatures. However, Ecr rapidly decreases with increasing T and becomes practically zero for T > Tcr. In this small but finite temperature window, we report how temperature affects (a) the electric current density, and (b) the Bloch-like frequencies.

  12. Control of Power in Parity-Time -Symmetric Lattices

    CERN Document Server

    Kozlov, Maksim

    2015-01-01

    We investigate wave transport properties of Parity-Time (PT) symmetric lattices that are periodically modulated along the direction of propagation. We demonstrate that in the regime of unbroken PT-symmetry the system Floquet-Bloch modes may interfere constructively leading to either controlled oscillations or linear power absorption and amplification occurring exactly at the phase transition point. The differential power response is effected by the overlap of the gain and loss system distribution with wave intensity pattern that is formed through Rabi oscillations engaging the coupled Floquet-Bloch modes.

  13. Identity Conflicts: A Doctrinal Change Needed?

    Science.gov (United States)

    2014-12-12

    differ from yesterday. ― Marc Bloch, Strange Defeat Introduction The purpose of this thesis is to examine whether the U.S. Army has accepted...Bloch, Marc. 1946. Strange Defeat: A Statement of Evidence Written in 1940. London: W. W. Norton. British Broadcasting Company (BBC). 2006. Iraqi...Raphael. 2010. “A Tale of Two Manuals.” Prism 2, no. 1: 87-100. Collier, Paul, and Anke Hoeffler. 1998. “On Economic Causes of Civil War.” Oxford

  14. Academician Mihail P. Kirpichnikov, Minister for Science and Technology, Russian Federation

    CERN Document Server

    Patrice Loïez

    2002-01-01

    Photo 01: Academician Mihail P. Kirpichnikov, Minister for Science and Technology, Russian Federation (white raincoat) visiting the CMS crystal laboratory with (from l. to r.) Ph. Bloch, N. Koulberg, L. Riabev, First Deputy-Minister, MINATOM; F. Grichaev and A.N. Skrinsky. Photo 02: Academician Mihail P. Kirpichnikov, Minister for Science and Technology, Russian Federation (centre) visiting the CMS crystal laboratory with (from l. to r.) N. Koulberg, M. Koutchina, L. Riabev, First Deputy-Minister, MINATOM; F. Grichaev, Ph. Bloch, A.N. Skrinsky, A. Petrov, V. Stanislavov.

  15. Mrs Hitler and her doctor.

    Science.gov (United States)

    Macleod, Sandy

    2005-12-01

    The doctor who attended the mother of Adolf Hitler in her terminal illness has been blamed as a cause of the Holocaust. The medical details recorded of this professional relationship are presented and discussed. Dr Bloch's medical care of Mrs Hitler was consistent with the prevailing medical practice of the management of fungating breast carcinoma. Indeed, the general practitioner's care and attention of the family appear to have been astute and supportive. There is nothing to suggest that Dr Bloch's medical care was other than competent. Doctors who have the (mis)fortune to professionally attend major figures of history may be unfairly viewed, despite their appropriate and adequate care.

  16. Control of power in parity-time symmetric lattices

    Science.gov (United States)

    Kozlov, Maksim; Tsironis, G. P.

    2015-10-01

    We investigate wave transport properties of parity-time (PT) symmetric lattices that are periodically modulated along the direction of propagation. We demonstrate that in the regime of unbroken PT-symmetry, the system Floquet-Bloch modes may interfere constructively leading to either controlled oscillations or power absorption and unlimited amplification occurring exactly at the phase-transition point. The differential power response is affected by the overlap of the gain and loss system distribution with wave intensity pattern that is formed through Rabi oscillations engaging the coupled Floquet-Bloch modes.

  17. Non-equilibrium analysis of the two-color operation in semiconductor quantum-well lasers

    Energy Technology Data Exchange (ETDEWEB)

    Baeumner, Ada; Koch, Stephan W. [Department of Physics and Material Science Center, Philipps University, Renthof 5, 35032 Marburg (Germany); Moloney, Jerome V. [Arizona Center of Mathematical Science and College of Optical Science, University of Arizona, Tucson 85721, Arizona (United States)

    2011-04-15

    The relevance of hole burning for stable two-color operation in semiconductor quantum-well lasers is studied using a non-equilibrium laser model on the basis of the semiconductor Maxwell-Bloch equations. The field propagation is described via a traveling-wave method. The polarization dynamics is computed using the semiconductor Bloch equations for the microscopic transition and occupation probabilities. Numerical examples for single- and dual-mode operation are presented for a microresonator model system. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Symmetry characterization of electrons and lattice excitations

    Directory of Open Access Journals (Sweden)

    Schober H.

    2012-03-01

    Full Text Available Symmetry concerns all aspects of a physical system from the electronic orbitals to structural and magnetic excitations. In this article we will try to elaborate the fundamental connection between symmetry and excitations. As excitations are manyfold in physical systems it is impossible to treat them exhaustively. We thus concentrate on the two topics of Bloch electrons and phonons. These two examples are complementary in the sense that Bloch electrons describe single particles in an external periodic potential while phonons exemplify a decoupled system of interacting particles. The way we develop the argument gives as by-product a short account of molecular orbitals and molecular vibrations.

  19. Modeling of optical fields in laser microcavities using a modal method

    DEFF Research Database (Denmark)

    Gregersen, Niels

    2013-01-01

    of adiabatic transitions emerge as powerful design tools to control the optical mode. In the modal method, the eld is expanded on the eigenmodes of z-invariant layers and on the Bloch modes of periodic sections. Using mode matching at the interfaces, the method gives direct access to re ection and transmission...... coecients describing the scattering of the optical modes, and the method is thus highly suitable for Bloch-wave engineering of the low-V cavity. As example we have used the modal method to propose the high-Q submicron-diameter micropillar geometry implementing an adiabatic cavity design as illustrated...

  20. A Study to Determine Methods to Improve Patient Awareness at Moncrief Army Hospital, Fort Jackson, South Carolina

    Science.gov (United States)

    1980-04-01

    3Bloch, p. 54. 41bid., p. 53 5Cunningham, p. 68 6Ibid., p. 67. 7Bloch, p. 53. 8Christina Maslach , "Burned-Out," Human Behavior, September 1976, p. 17...Progresa, June 1972, pp. 42- 4 9.. Maslach , Christina. "Burned Out." Human Behavior, September 19.76, pp. 16-21. Sasser, Earl W. Jr. and Frank S...Health Services Command, Fort Sam Houston, Texas, July 1977. Veninga, Robert. "Administrator Burnout - Causes and Cures." Hospital Progress, February 1979

  1. Evaluation of Metabolic Enzymes in Response to Excel Mera 71, a Glyphosate-Based Herbicide, and Recovery Pattern in Freshwater Teleostean Fishes

    OpenAIRE

    Palas Samanta; Sandipan Pal; Aloke Kumar Mukherjee; Apurba Ratan Ghosh

    2014-01-01

    Metabolic enzymes such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were evaluated in Indian teleostean fishes, namely, Anabas testudineus (Bloch) and Heteropneustes fossilis (Bloch), for an exposure to 30 days of Excel Mera 71 (17.2 mg/L), a glyphosate formulation, and subsequent depuration under Liv.52, a plant extract at a dose of 187.5 mg/d/250 L for the same period in the same tissues under laboratory condition. ALT activity was sign...

  2. A Higgs at 125.1 GeV and baryon mass spectra derived from a Common U(3) Lie group framework

    DEFF Research Database (Denmark)

    Trinhammer, Ole; Bohr, Henrik; Jensen, Mogens O Stibius

    2015-01-01

    Baryons are described by a Hamiltonian on an intrinsic U(3) Lie group configuration space with electroweak degrees of freedom originating in specific Bloch wave factors. By opening the Bloch degrees of freedom pairwise via a U(2) Higgs mechanism, the strong and electroweak energy scales become...... related to yield the Higgs mass 125.085+/-0.017 GeV and the usual gauge boson masses. From the same Hamiltonian we derive both the relative neutron to proton mass ratio and the N and Delta mass spectra. All compare rather well with the experimental values. We predict neutral flavour baryon singlets...

  3. Selection rule for Dirac-like points in two-dimensional dielectric photonic crystals

    KAUST Repository

    Li, Yan

    2013-01-01

    We developed a selection rule for Dirac-like points in two-dimensional dielectric photonic crystals. The rule is derived from a perturbation theory and states that a non-zero, mode-coupling integral between the degenerate Bloch states guarantees a Dirac-like point, regardless of the type of the degeneracy. In fact, the selection rule can also be determined from the symmetry of the Bloch states even without computing the integral. Thus, the existence of Dirac-like points can be quickly and conclusively predicted for various photonic crystals independent of wave polarization, lattice structure, and composition. © 2013 Optical Society of America.

  4. 29 March 2011 - Ninth President of Israel S.Peres welcomed by CERN Director-General R. Heuer who introduces Council President M. Spiro, Director for Accelerators and Technology S. Myers, Head of International Relations F. Pauss, Physics Department Head P. Bloch, Technology Department Head F. Bordry, Human Resources Department Head A.-S. Catherin, Beams Department Head P. Collier, Information Technology Department Head F. Hemmer, Adviser for Israel J. Ellis, Legal Counsel E. Gröniger-Voss, ATLAS Collaboration Spokesperson F. Gianotti, Former ATLAS Collaboration Spokesperson P. Jenni, Weizmann Institute G. Mikenberg, CERN VIP and Protocol Officer W. Korda.

    CERN Multimedia

    Maximilien Brice

    2011-01-01

    During his visit he toured the ATLAS underground experimental area with Giora Mikenberg of the ATLAS collaboration, Weizmann Institute of Sciences and Israeli industrial liaison office, Rolf Heuer, CERN’s director-general, and Fabiola Gianotti, ATLAS spokesperson. The president also visited the CERN computing centre and met Israeli scientists working at CERN.

  5. New Records and Name Changes for the Orchids in the Solomon Islands

    Directory of Open Access Journals (Sweden)

    Tian-Chuan Hsu

    2016-03-01

    Full Text Available One genus (Anoectochilus and 12 species (Agrostophyllum neoguineense, Anoectochilus papuanus, Arundina graminifolia, Bulbophyllum aemulum, B. bisepalum, B. nubigenum, B. ochroleucum, B. phreatiopse, Corybas solomonensis, Crepidium laevis, Didymoplexis striata, Epipogium roseum of orchids (Orchidaceae are first recorded to the flora of the Solomon Islands during the 2012–2015 field expeditions. Geographic data, ecological and taxonomic notes and illustrations of those species are provided. A new combination (Pinalia oligotricha and a new name (Dendrobium bougainvilleanum are also proposed for fitting recent systematic alterations within Orchidaceae.

  6. GCMS Determination of Organochlorine Pesticides (OCPs in Fish from River Cauvery and Veeranam Lake

    Directory of Open Access Journals (Sweden)

    R. Bhuvaneshwari

    2012-01-01

    Full Text Available Organochlorine Pesticides (OCPs were analyzed using Gas Chromatography-Mass Spectrometer (Selective Ion Monitoring mode in the muscle tissues of five fish species such as O. mossambicus, L. parsia, E. suretensis, C. striata and S. wynaadensis from seven locations of River Cauvery and one location in Veeranam Lake. OCPs viz., DDTs, HCHs, CHLs, cyclodienes, heptachlor, HCB and mirex were detected with varying concentrations among species and locations. Mirex which was not reported in the fish tissues elsewhere reported in this study. The study on the risk associated with the consumption of fish species that had higher concentrations of aldrin, dieldrin and mirex showed significant carcinogenic risk to the human beings.

  7. Gifles de la Tourett's Disease a Single case study A Discussion on Aetiology and Treatment

    Directory of Open Access Journals (Sweden)

    C. Izadi

    1978-01-01

    Full Text Available A case of Gille de la Tourett's syndrome is reported and discussed 111 the light of conflicting views on the aetiology of the condition. It is hypothesized that if Tourette's syndrome is to be considered as a sort of reaction against adaption to an unhealthy environment, this reaction and its continuity can be attributed to permanent eNS damage (Probably in the area of corpora striata beginning in childhood. Treatment with haloperidol is suggested as a most effective method of symptomatic treatment.

  8. Evaluation of nail lines: Color and shape hold clues.

    Science.gov (United States)

    Lipner, Shari R; Scher, Richard K

    2016-05-01

    Nail lines are a common presenting finding. A thorough inspection of the fingernails and toenails is an integral part of the complete physical examination. An understanding of basic nail anatomy and familiarity with several basic types of nail line enable the clinician to diagnose and treat nail disorders and to recognize underlying systemic diseases, as each type of nail line has a particular differential diagnosis. The authors review leukonychia striata (white lines), longitudinal melanonychia (brown-black lines), longitudinal erythronychia (red lines), and nail-plate grooves (Beau lines). Copyright © 2016 Cleveland Clinic.

  9. Diseño agronómico y estructural de un prototipo de invernadero de bambú

    OpenAIRE

    Romero Méndez, Mauricio Jesús

    2013-01-01

    El uso del bambú en sustitución del acero en la construcción de invernaderos puede aportar ventajas tales como reducir el alto costo de los materiales y el impacto sobre el medio ambiente. Para el presente estudio, se plantearon tres etapas para cada uno de los siguientes objetivos: 1. Determinar las principales propiedades mecánicas y físicas de cuatro variedades de bambú: Bambusa vulgaris var. striata, Bambusa vulgaris "verde", Bambusa oldhamii y Gigantochloa verticillata col...

  10. Freshwater ascomycetes: new and noteworthy species from aquatic habitats in Florida.

    Science.gov (United States)

    Raja, Huzefa A; Shearer, Carol A

    2008-01-01

    As part of a distributional study of freshwater ascomycetes in Florida, a number of new taxa were encountered. The new taxa include six Sordariomycetes, Aniptodera megaloascocarpa sp. nov., Flammispora pulchra sp. nov., Hanliniomyces hyaloapicalis gen. et sp. nov., Lockerbia striata sp. nov., Phomatospora triseptata sp. nov. and Physalospora limnetica sp. nov., and three Dothideomycetes, Caryospora obclavata sp. nov., Lepidopterella tangerina sp. nov. and Ophiobolus shoemakeri sp. nov. These taxa are described and illustrated. Six additional species are reported from Florida for the first time; among them, two species are new reports from freshwater habitats.

  11. A case report of focal dermal hypoplasia-Goltz syndrome

    Directory of Open Access Journals (Sweden)

    Sheela Bharani

    2013-01-01

    Full Text Available Goltz syndrome is a rare multisystem disorder with cutaneous, ocular, dental and skeletal abnormalities. Other mesoectodermal abnormalities are also present. Its hallmark is thinning of the dermis resulting subcutaneous fat herniation. The present case is a 5 year old girl having linear skin atrophy with fat herniation, skeletal abnormalities in the form of polysyndactyly, facial asymmetry, squint with coloboma iris, deformed pinna, abnormal dentition, umbilical hernia along with osteopathia striata of long bones which is consistent with Goltz syndrome. We are presenting this case due to its rarity.

  12. A revision of the genus Mecistostethus Marseul (Histeridae, Histerinae, Exosternini

    Directory of Open Access Journals (Sweden)

    Michael Caterino

    2012-08-01

    Full Text Available We revise the genus Mecistostethus Marseul, sinking the monotypic genus Tarsilister Bruch as a junior synonym. Mecistostethus contains six valid species: M. pilifer Marseul, M. loretoensis (Bruch, comb. n., M. seagorum sp. n., M. carltoni sp. n., M. marseuli sp. n., and M. flechtmanni sp. n. The few existing records show the genus to be widespread in tropical and subtropical South America, from northern Argentina to western Amazonian Ecuador and French Guiana. Only a single host record associates one species with the ant Pachycondyla striata Smith (Formicidae: Ponerinae, but it is possible that related ants host all the species.

  13. A revision of the genus Mecistostethus Marseul (Histeridae, Histerinae, Exosternini).

    Science.gov (United States)

    Caterino, Michael S; Tishechkin, Alexey K; Dégallier, Nicolas

    2012-01-01

    We revise the genus Mecistostethus Marseul, sinking the monotypic genus Tarsilister Bruch as a junior synonym. Mecistostethus contains six valid species: Mecistostethus pilifer Marseul, Mecistostethus loretoensis (Bruch), comb. n., Mecistostethus seagorumsp. n., Mecistostethus carltonisp. n., Mecistostethus marseulisp. n., and Mecistostethus flechtmannisp. n. The few existing records show the genus to be widespread in tropical and subtropical South America, from northern Argentina to western Amazonian Ecuador and French Guiana. Only a single host record associates one species with the ant Pachycondyla striata Smith (Formicidae: Ponerinae), but it is possible that related ants host all the species.

  14. Theoretical investigation of the excitonic semiconductor response for varying material thickness: Transition from quantum well to bulk

    DEFF Research Database (Denmark)

    Bischoff, Svend; Knorr, A; Koch, S.W.

    1997-01-01

    For semiconductor slabs with thicknesses varying from the two-dimensional to the three-dimensional limit the linear optical response is calculated numerically by solving the semiconductor Maxwell-Bloch equations. For short-pulse excitation the spatiotemporal dynamics of the electronic mode...

  15. Dynamical theory : Application to spin-echo resolved grazing incidence scattering from periodic structures

    NARCIS (Netherlands)

    Ashkar, R.; Schaich, W.L.; De Haan, V.O.; Van Well, A.A.; Dalgliesh, R.; Plomp, J.; Pynn, R.

    2011-01-01

    Neutron spin-echo resolved grazing incidence scattering (SERGIS) measurements performed on a silicon diffraction grating with a rectangular profile were shown in our previous publications to be well explained by dynamical theory calculations. The theory is based on a Bloch wave expansion of the

  16. Balts show strong notes in Grammy Awards

    Index Scriptorium Estoniae

    2005-01-01

    Los Angeleses 8. veebr. Grammy Awards nominantide seas läti laulja Elina Garanca, dirigendid Paavo Järvi (Schumann "Cello Concerto" and Bloch's "Schelomo") ja Maris Jansons. Eelmisel aastal pälvis Grammy teos Sibelius "Cantatas" (esitajad Ellerheina tütarlastekoor Ester Loitme juhatusel, Eesti Rahvusmeeskoor, ERSO, dirigendid Ants Soots ja Paavo Järvi)

  17. Todorov, Levinas and anti-totalitarian humanism: A perspective on ...

    African Journals Online (AJOL)

    p1243322

    social ideals – Prophetic hope in Emmanuel Levinas and Ernst Bloch) completed at the. Institute of Philosophy, Katholieke Universiteit Leuven (Belgium) in 2005. ... utopias pursue the same obstinate dream: To realize a communion in collective life as perfect as that of conjugal symbiosis.” See also Joachim Fest, Der ...

  18. Download this PDF file

    African Journals Online (AJOL)

    Owner

    wrote of Lagos: Many of the much touted values of contemporary global capital and its prophetic organizational models of dispersal and discontinuity, federalism and flexibility, have .... dreaming and have few ambitions. (qtd in Nebandla 19). Other “impeded futures” (Bloch 33) are the result of the toll of AIDS or high levels of.

  19. Dynamical symmetry breaking of lambda- and vee-type three-level ...

    Indian Academy of Sciences (India)

    between the SU(N) symmetry and the N-level system in general, was investigated extensively in the recent past .... Proceeding in the same way, the semiclassical vee-type three-level system can be written as. HV = HV ...... dimensional Bloch equations and non-linear constants for different configurations of the three-level ...

  20. Introduction to spintronics

    CERN Document Server

    Bandyopadhyay, Supriyo

    2008-01-01

    The Early History of Spin Spin The Bohr Planetary Model and Space Quantization The Birth of "Spin" The Stern-Gerlach Experiment The Advent of Spintronics The Quantum Mechanics of Spin Pauli Spin Matrices The Pauli Equation and Spinors More on the Pauli Equation Extending the Pauli Equation - the Dirac Equation The Time Independent Dirac Equation Appendix The Bloch Sphere The Spinor and the "Qubit" The Bloch Sphere Concept Evolution of a Spinor Spin-1/2 Particle in a Constant Magnetic Field: Larmor Precession Preparing to Derive the Rabi Formula The Rabi Formula The Density Matrix The Density Matrix Concept: Case of a Pure State Properties of the Density Matrix Pure Versus Mixed State Concept of the Bloch Ball Time Evolution of the Density Matrix: Case of Mixed State The Relaxation Times T1 and T2 and the Bloch Equations Spin Orbit Interaction Spin Orbit Interaction in a Solid Magneto-Electric Sub-Bands in Quantum Confined Structures in the Presence of Spin-Orbit Interaction Dispersion Relations of Spin Resolv...

  1. Antropologie en geschiedenis

    NARCIS (Netherlands)

    Kuiper, Yme; Vries, P.H.H.

    1989-01-01

    Since the 1970s there has been a rapprochement in Academia between anthropology and history. Who were the most important advocates of this trend? Forerunners were the British anthropologist and Africanist E.E. Evans-Pritchard and the French historian Marc Bloch. Recent representatives of this trend

  2. Ethical Ideologies: Do They Affect Shopping Behaviors and Perceptions of Morality?

    Science.gov (United States)

    Cho, Hyeon; Yoo, Jeong-Ju; Johnson, Kim K. P.

    2005-01-01

    Counterfeiting is a serious problem facing several industries, including the medical, agricultural, and apparel industries (Bloch, Bush, & Campbell, 1993). The authors investigated whether ethical viewpoints affect perceptions of the morality of particular shopping behaviors, attitudes toward counterfeit products, and intentions to purchase such…

  3. South African Medical Journal - Vol 68, No 1 (1983)

    African Journals Online (AJOL)

    The dilemma of the creatine kinase cardiospecific iso-enzyme (CK-MB) in marathon runners · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. T. H. Diamond, R. Smith, A. P. Goldman, D. P. Myburgh, J.M. Bloch, F Visser, 37-41 ...

  4. Dispersive optical bistability in a nonideal Fabry-Perot cavity II. Numerical results on side-mode instabilities

    NARCIS (Netherlands)

    van Wonderen, A.J.; Suttorp, L.G.

    1991-01-01

    Instabilities in the nearest side-modes are predicted for dispersive optical bistability in a nonideal Fabry-Perot cavity. The results are based on a linear stability analysis of the Maxwell-Bloch equations. This analysis leads to a boundary value problem for a four-dimensional set of linear

  5. Optimally cloned binary coherent states

    DEFF Research Database (Denmark)

    Mueller, C. R.; Leuchs, G.; Marquardt, Ch

    2017-01-01

    Binary coherent state alphabets can be represented in a two-dimensional Hilbert space. We capitalize this formal connection between the otherwise distinct domains of qubits and continuous variable states to map binary phase-shift keyed coherent states onto the Bloch sphere and to derive...

  6. Nonlinear emission from dark anapole modes and route to all-dielectric metamaterial near-field lasers

    KAUST Repository

    Gongora, J. S. Totero

    2016-08-29

    By employing ab-initio simulations of Maxwell-Bloch equations with a source of quantum noise, we study a new laser concept based on photonic dark-matter nanostructures that emit only in the near-field, with no far-field radiation pattern

  7. Near-Field Nanolasers based on Nonradiating Anapole Modes

    KAUST Repository

    Gongora, J. S. Totero

    2016-05-31

    By employing ab-initio simulations of Maxwell-Bloch equations with a source of quantum noise, we study a new laser concept based on photonic dark-matter nanostructures that emit only in the near-field, with no far-field radiation pattern.

  8. Schrödinger operators on a periodically broken zigzag carbon ...

    Indian Academy of Sciences (India)

    In this paper, we study the spectra of Schrödinger operators on zigzag carbon nanotubes, which are broken by abrasion or during refining process. Throughout this paper, we assume that the carbon nanotubes are broken periodically and we deal with one of those models. Making use of the Floquet–Bloch theory, we ...

  9. A rigorous proof of the Landau-Peierls formula and much more

    DEFF Research Database (Denmark)

    Briet, Philippe; Cornean, Horia; Savoie, Baptiste

    2012-01-01

    We present a rigorous mathematical treatment of the zero-field orbital magnetic susceptibility of a non-interacting Bloch electron gas, at fixed temperature and density, for both metals and semiconductors/insulators. In particular, we obtain the Landau-Peierls formula in the low temperature...

  10. Biochemical composition and caloric content in the sand whiting Sillago sihama (Forsskal), from Zuari Estuary, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Shamsan, E.F.; Ansari, Z.A.

    -44. Jafri, A. K. 1969. Seasonal changes in the biochemical composition of the freshwater cat fish Wallagoni attu (Bloch). Hydrobiologia Acta. 33(3&4): 497-505. Jayasree, V., A. H. Parulekar, A.H., S. Wahidulla, S. and Kamat, S.Y. 1994. Seasonal changes...

  11. Étude de quelques paramètres de la reproduction de Coryphaena ...

    African Journals Online (AJOL)

    Mullus surmuletus (poisson Mullidae) dans le Nord du golfe de Gascogne : Reproducteurs, larves et juvéniles. Thèse de Doctorat, Université de Bretagne. Occidentale, 177 p. Rey JC, Alot E, Ramos A. 1984. Synopsis biológica del bonito, Sardasarda (Bloch) del. Mediterráneo y Atlántico. Este. Collect. Vol. Sci. Pap. ICCAT,.

  12. Intentionality, morality, and the incest taboo in Madagascar

    Directory of Open Access Journals (Sweden)

    Paulo eSousa

    2016-04-01

    Full Text Available In a recent article (Astuti & Bloch, 2015, cognitive anthropologists Rita Astuti and Maurice Bloch claim that the Malagasy are ambivalent as to whether considerations of intentionality are relevant to moral judgments concerning incest and its presumed catastrophic consequences: when making moral judgments about those who commit incest, the Malagasy take into account whether the incest is intentional or not, but, when making moral judgments relating to incest’s catastrophic consequences, they do not take intentionality into account. Astuti & Bloch explain the irrelevance of intentionality in terms of incest entailing such a fundamental attack on the transcendental social order that the Malagasy become dumbfounded and leave aside considerations of intentionality. Finally, they claim that a similar dumbfound reaction is what is involved in the moral dumbfounding concerning incest that social psychologist Jonathan Haidt has found in the US. In this paper, we argue that (i Astuti & Bloch are unclear about many aspects of their claims (in particular, about the moral judgments at stake, (ii they do not provide sufficient evidence that considerations of intentionality are deemed irrelevant to moral judgments relating to incest’s presumed catastrophic consequences (and hence for the claim that the Malagasy are ambivalent, (iii their hypothesis that conceiving of incest as an attack on the transcendental social renders considerations of intentionality irrelevant lacks coherence, and (iv the extension of their explanatory account to the moral dumfounding of American students in Haidt’s well-known scenario of intentional incest is unwarranted.

  13. The Faraday effect revisited: General theory

    DEFF Research Database (Denmark)

    Cornean, Horia Decebal; Nenciu, Gheorghe; Pedersen, Thomas Garm

    2006-01-01

    of the strength of the magnetic field B. Then the linear term in B of this expansion is written down in terms of the zero magnetic field Green function and the zero field current operator. In the periodic case, the linear term in B of the conductivity tensor is expressed in terms of zero magnetic field Bloch...

  14. Using Gait Dynamics to Estimate Load from a Body-Worn Accelerometer

    Science.gov (United States)

    2016-02-05

    Hidalgo Ltd., Cambridge, UK) physiological status monitor, positioned on the left side of the chest below the armpit. The Equivital EQ-02...Salisbury, E., & Paydarfar, D. (2011, November). Using physiological signals to predict apnea in preterm infants. In Signals, Systems and Computers...Indic, P., Bloch- Salisbury, E., & Paydarfar, D. (2013, May). Individualized apnea prediction in preterm infants using cardio-respiratory and movement

  15. Tools and methods for teaching magnetic resonance concepts and techniques

    DEFF Research Database (Denmark)

    Hanson, L.G.

    2012-01-01

    and MRI education. After a few minutes of use, any user with minimal experience of magnetism will be able to explain the basic magnetic resonance principle. A second piece of software, the Bloch Simulator, aims much further, as it can be used to demonstrate and explore a wide range of phenomena including...

  16. asking questions for higher order thinking in visual literacy

    African Journals Online (AJOL)

    ground of learners, lack of resources, poor teacher pedagogical content knowledge, lack of professional collaborative practices and poor instructional leadership (Christie,. 1998, 2008; Bloch, 2009) contribute to the literacy and education crisis. However, drawing on evidence from my role as quality assurer of a Grade 12 ...

  17. Quantum kinetic theory of the chiral anomaly

    Science.gov (United States)

    Sekine, Akihiko; Culcer, Dimitrie; MacDonald, Allan H.

    2017-12-01

    We present a general quantum kinetic theory of low-field magnetotransport in weakly disordered crystals that accounts fully for the interplay between electric-field-induced interband coherence, Bloch-state scattering, and an external magnetic field. The quantum kinetic equation we derive for the Bloch-state density matrix naturally incorporates the momentum-space Berry phase effects whose influence on Bloch-state wave-packet dynamics is normally incorporated into transport theory in an ad hoc manner. The Berry phase correction to the momentum-space density of states in the presence of an external magnetic field implied by semiclassical wave-packet dynamics is captured by our theory as an intrinsic density-matrix response to a magnetic field. We propose a simple and general procedure for expanding the linear response of the Bloch-state density matrix to an electric field in powers of magnetic field. As an illustration, we apply our theory to magnetotransport in Weyl semimetals. We show that the chiral anomaly (positive magnetoconductivity quadratic in magnetic field) that appears when separate Fermi surface pockets surround distinct Weyl points survives only when intervalley scattering is very weak compared to intravalley scattering.

  18. Paavo Järvi salvestis on Grammy nominent

    Index Scriptorium Estoniae

    2005-01-01

    Prantsuse Raadio Filharmooniaorkester Paavo Järvi dirigeerimisel ning norra tshellomängija Truls Mork kandideerivad tänavu süvamuusika kategoorias ning sümfooniaorkestri saatel esineva parima solisti alajaotuses plaadiga "Schumann: Cello Concerto; Bloch: Schelomo" USA muusikaauhinnale Grammy

  19. A Proposed Curriculum on Death and Dying for the Allied Health Student.

    Science.gov (United States)

    Dietrich, Marie C.

    1980-01-01

    This article summarizes the existing curricular models on death education for health professions students. A proposed course design for allied health professions students modified from Bloch's medical education objectives for a thanatology course is presented. The development of listening skills is given special emphasis. (Author/CT)

  20. Intentionality, Morality, and the Incest Taboo in Madagascar

    Science.gov (United States)

    Sousa, Paulo; Swiney, Lauren

    2016-01-01

    In a recent article (Astuti and Bloch, 2015), cognitive anthropologists Astuti and Bloch claim that the Malagasy are ambivalent as to whether considerations of intentionality are relevant to moral judgments concerning incest and its presumed catastrophic consequences: when making moral judgments about those who commit incest, the Malagasy take into account whether the incest is intentional or not, but, when making moral judgments relating to incest’s catastrophic consequences, they do not take intentionality into account. Astuti and Bloch explain the irrelevance of intentionality in terms of incest entailing such a fundamental attack on the transcendental social order that the Malagasy become dumbfounded and leave aside considerations of intentionality. Finally, they claim that a similar dumbfound reaction is what is involved in the moral dumbfounding concerning incest that social psychologist Jonathan Haidt has found in the US. In this article, we argue that (i) Astuti and Bloch are unclear about many aspects of their claims (in particular, about the moral judgments at stake), (ii) they do not provide sufficient evidence that considerations of intentionality are deemed irrelevant to moral judgments relating to incest’s presumed catastrophic consequences (and hence for the claim that the Malagasy are ambivalent), (iii) their hypothesis that conceiving of incest as an attack on the transcendental social renders considerations of intentionality irrelevant lacks coherence, and (iv) the extension of their explanatory account to the moral dumfounding of American students in Haidt’s well-known scenario of intentional incest is unwarranted. PMID:27092099