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Effect of Azomite on growth performance, immune function and tibia breaking strength of broiler chickens during starter period. Anim Biotechnol 2022; 33:1539-1544. [PMID: 33938381 DOI: 10.1080/10495398.2021.1914644] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This study was examined to investigate the effect of Azomite (AZO) on the growth performance, immune function, and bone mineralization of broiler chickens. A total of 240-d old male chicks were randomly assigned into four treatments with six replicates (n = 10), which included control (basal diet), basal diet +0.25% AZO, basal diet + 0.50% AZO and basal diet + kitasamycin as antibiotic growth promoter (AGP). The results indicate that live body weight (LBW), average daily gain (ADG) and feed conversion ratio (FCR) were significantly (p < .05) improved in AZO 0.25% and 0.50% than the control. The weight of bursa of Fabricus was significantly (p < .05) higher in AZO-0.25% and AZO-0.50% than control. Total protein (TP), globulin, IgA and IgG levels were significantly (p < .05) increased with AZO supplemented treatments. Tibia diameter tibia breaking strength was significantly (p < .05) increased in AZO- 0.25% and AZO-0.50% treatment. In conclusion, the results indicated that addition of AZO at the doses of 0.25% and 0.50% in the diet had beneficial effects on growth performance, immune functions and tibia breaking strength.
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Health benefits of carotenoids and potential application in poultry industry: A review. J Anim Physiol Anim Nutr (Berl) 2020; 104:1809-1818. [PMID: 32333620 DOI: 10.1111/jpn.13375] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 12/15/2022]
Abstract
Carotenoids are one of the widespread and ubiquitous lipid-soluble pigments that produce a wide range of colours which are universally found in various plants, microalgae, bacteria and fungi. Recently, interest in using carotenoids as feed ingredients has increased markedly owing to their bioactive and health-promoting properties. In terms of applications, carotenoid-rich products are widely available in the form of food and feed additive, supplements and natural colourants. Carotenoids play a versatile biological role that contributes to therapeutic effects, including anticancer, immunomodulators, anti-inflammatory, antibacterial, antidiabetic and neuroprotective. Dietary supplementation of carotenoids not only improves the production performance and health of poultry birds, but also enhances the quality of egg and meat. Several studies have suggested that the supplementation of plant derived carotenoids revealed numerous health-promoting activities in poultry birds. Carotenoids reduce the oxidative stress in pre-hatched and post-hatched birds through different mechanisms, including quench free radicals, activating antioxidant enzymes and inhibiting the signalling pathways. Use of carotenoids in poultry feed as a part of nutrient that confers bird health and improve product quality. Carotenoids play a critical role for the pigmentation of egg yolk, skin, legs, beak, comb, feather and fat. Birds consumed carotenoid deficient diet resulting hues of their egg yolk or pale coloured skin. Therefore, uniform pigmentation generally indicates the health status and quality of the poultry products. This review aims to gather recent information regarding bioactive properties of carotenoids and highlight pharmaceutical and health beneficial effects of carotenoids for the poultry industry. Additionally, it explores the importance of carotenoids as alternative feed ingredients for poultry to boost the production performance and replace synthetic medicine and nutrients.
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Nutritional applications and beneficial health applications of green tea and l-theanine in some animal species: A review. J Anim Physiol Anim Nutr (Berl) 2020; 104:245-256. [PMID: 31595607 DOI: 10.1111/jpn.13219] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 08/26/2019] [Accepted: 09/10/2019] [Indexed: 02/05/2023]
Abstract
Green tea (Camellia sinensis) is a popular herbal plant with abundant health benefits, and thus, it has been used as a potent antioxidant for a long time. Based on the available literature, the diversity and the availability of multifunctional compounds in green tea offer its noteworthy potential against many diseases such as liver and heart diseases, inflammatory conditions and different metabolic syndromes. Owing to its bioactive constituents including caffeine, amino acids, l-theanine, polyphenols/flavonoids and carbohydrates among other potent molecules, green tea has many pharmacological and physiological effects. The effects of green tea include anti-oxidative, anti-inflammatory, anti-arthritic, anti-stress, hypolipidaemic, hypocholesterolaemic, skin/collagen protective, hepatoprotective, anti-diabetic, anti-microbial, anti-infective, anti-parasitic, anti-cancerous, inhibition of tumorigenesis and angiogenesis, anti-mutagenic, and memory and bone health-improving activities. Apart from its utilization in humans, green tea has also played a significant role in livestock production such as in dairy, piggery, goatry and poultry industries. Supplementation of animal feeds with green tea and its products is in line with the modern concepts of organic livestock production. Hence, incorporating green tea or green tea by-products into the diet of poultry and other livestock can enhance the value of the products obtained from these animals. Herein, an effort is made to extend the knowledge on the importance and useful applications of green tea and its important constituents in animal production including poultry. This review will be a guideline for researchers and entrepreneurs who want to explore the utilization of feeds supplemented with green tea and green tea by-products for the enhancement of livestock production.
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In ovo delivery of various biological supplements, vaccines and drugs in poultry: current knowledge. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2019; 99:3727-3739. [PMID: 30637739 DOI: 10.1002/jsfa.9593] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 12/30/2018] [Accepted: 01/01/2019] [Indexed: 06/09/2023]
Abstract
The technique of delivering various nutrients, supplements, immunostimulants, vaccines, and drugs via the in ovo route is gaining wide attention among researchers worldwide for boosting production performance, immunity and safeguarding the health of poultry. It involves direct administration of the nutrients and biologics into poultry eggs during the incubation period and before the chicks hatch out. In ovo delivery of nutrients has been found to be more effective than post-hatch administration in poultry production. The supplementation of feed additives, nutrients, hormones, probiotics, prebiotics, or their combination via in ovo techniques has shown diverse advantages for poultry products, such as improved growth performance and feed conversion efficiency, optimum development of the gastrointestinal tract, enhancing carcass yield, decreased embryo mortality, and enhanced immunity of poultry. In ovo delivery of vaccination has yielded a better response against various poultry pathogens than vaccination after hatch. So, this review has aimed to provide an insight on in ovo technology and its potential applications in poultry production to deliver different nutrients, supplements, beneficial microbes, vaccines, and drugs directly into the developing embryo to achieve an improvement in post-hatch growth, immunity, and health of poultry. © 2019 Society of Chemical Industry.
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The Promising Pharmacological Effects and Therapeutic/Medicinal Applications of Punica Granatum L. (Pomegranate) as a Functional Food in Humans and Animals. ACTA ACUST UNITED AC 2018; 12:24-38. [PMID: 29473532 DOI: 10.2174/1872213x12666180221154713] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 02/11/2018] [Accepted: 02/15/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND Punica granatum L. (pomegranate), is a shrub mostly available in the Mediterranean Sea region. The fruits have gained the substantial attention among researchers due to their promising biological activities including anti-inflammatory, antibacterial, antidiarrheal, immune modulatory, antitumor, wound healing and antifungal that have been attributed to various constituents of seeds, bark, juice, pericarp, and leaf of this tree across the globe. The phenolic compounds of pomegranate have been documented to possess numbers of prophylactic and therapeutic utilities against various pathological infections as well as non-infectious disorders. OBJECTIVE The current review expedites the pharmacological role of Punica granatum L. in curing elements related to infectious and non-infectious disorders. METHODS The current review is based on literature and patents already available on various scientific databases highlighting the role of Punica granatum along with its therapeutic potentials against infectious and non-infectious disorders. The databases included under study were PubMed, Med line, PubMed Central, Science Direct and few other scientific databases. The information obtained through these diverse databases is compiled, critically interpreted and presented in the current study. RESULTS Multi-dimensional beneficial application of pomegranate plant is recorded. The pomegranate seed oil has phytoestrogenic compounds and the fruit is rich in phenolic compounds with strong antioxidant activity. The fruit and bark of pomegranate are used against intestinal parasites, dysentery, and diarrhea in different animals and human models. Since the ancient time the juice and seeds had considered the best therapy for throat and heart disorders. Ellagic acid is one of the main components of pomegranate with potent antioxidant activity. Results from different studies reported that Punica granatum L or its byproducts can be used as natural food additives in human and animal nutrition in order to boost immunity, microbial safety and provide the housing environment without affecting body weight gain. In addition, Punica granatum L. byproducts can modulate immune function and gut microbiota of broiler chickens as well as reduce the odorous gas emissions from excreta. Naturally occurring polyphenols in a pomegranate can be a potential alternative medicine for the prevention of avian Colibacillosis diseases and can also be used as an intestine astringent to relieve diarrhea and enteritis in chickens. CONCLUSION The present review gives the insight towards major components of pomegranate as well as their pharmacological activities against pathological disorders. In spite of many beneficial properties of Punica granatum L., more research evidence on a molecular basis is needed to find out the molecular mechanism of action in various animals and human models to validate the usefulness of Punica granatum L. as a potent therapeutic agent.
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Clinical efficiency and safety of Hsp90 inhibitor Novobiocin in avian tibial dyschondroplasia. J Vet Pharmacol Ther 2018; 41:902-911. [PMID: 30004119 DOI: 10.1111/jvp.12692] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 06/12/2018] [Indexed: 12/21/2022]
Abstract
Tibial dyschondroplasia (TD) is a bone defect of broilers and other poultry birds that disturbs growth plate and it causes lameness. Previously we evaluated differential expression of multiple genes involved in growth plate angiogenesis and reported the safety and efficacious of medicinal plant root extracted for controlling TD. In this study, clinical and protective effect of an antibiotic Novobiocin (Hsp90 inhibitor) and expression of Hsp90 and proteoglycan aggrecan was examined. The chicks were divided into three groups; Control, thiram-induced TD, and Novobiocin injected TD. After the induction of TD, the Novobiocin was administered through intraperitoneal route to TD-affected birds until the end of the experiment. The expressions and localization of Hsp90 were evaluated by qRT-PCR, immunohistochemistry (IHC) and western blot, respectively. Morphological, histological examinations, and serum biomarker levels were evaluated to assess specificity and protective effects of Novobiocin. The results showed that TD causing retarded growth, enlarged growth plate, distended chondrocytes, irregular columns of cells, decreased antioxidant capacity, reduced protein levels of proteoglycan aggrecan, and upregulated in Hsp90 expression (p < 0.05) in dyschondroplastic birds as compared with control. Novobiocin treatment restored growth plate morphology, reducing width, stimulated chondrocyte differentiation, sprouting blood vessels, corrected oxidative imbalance, decreased Hsp90 expressions and increased aggrecan level. Novobiocin treatment controlled lameness and improved growth in broiler chicken induced by thiram. In conclusion, the accumulation of the cartilage and up-regulated Hsp90 are associated with TD pathogenesis and irregular chondrocyte morphology in TD is along with reduced aggrecan levels in the growth plate. Our results indicate that Novobiocin treatment has potential to reduce TD by controlling the expression of Hsp90 in addition to improve growth and hepatic toxicity in broiler chicken.
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Productive performance, egg quality, hematological parameters and serum chemistry of laying hens fed diets supplemented with certain fat-soluble vitamins, individually or combined, during summer season. ACTA ACUST UNITED AC 2018; 5:49-55. [PMID: 30899809 PMCID: PMC6407074 DOI: 10.1016/j.aninu.2018.04.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 04/04/2018] [Accepted: 04/09/2018] [Indexed: 01/18/2023]
Abstract
This present study aimed to determine the efficacy of supplementing layer diets with vitamin A (0, 8,000 and 16,000 IU/kg diet) and vitamin E (0, 250 and 500 mg/kg diet) either individually or in combination on egg production and quality, and blood hematology and chemistry of birds reared under summer conditions. A total of 135 Bovans Brown laying hens were distributed to 9 treatment groups with 5 replicates of 3 hens/pen in a 3 × 3 factorial design. A significant improvement in feed conversion ratio (FCR) was observed as supplementary vitamin A or E increased (P ≤ 0.01). Hens fed diets supplemented with 16,000 IU vitamin A plus 500 mg vitamin E/kg diet had the best FCR among all groups. Egg quality traits were not significantly affected by the interaction of vitamin A and vitamin E levels. There was a significant increase in monocytes (P ≤ 0.01) and a decrease in basophils counts (P ≤ 0.05) in response to vitamin E. Significant decreases were observed in packed cell volume (PCV), thyroxine (T4), alanine transferase (ALT), albumin, total cholesterol and total lipids ( (P ≤ 0.05 or P ≤ 0.01) P ≤ 0.01) , and increases were observed in serum concentrations of globulin (P ≤ 0.05) and calcium (P ≤ 0.01) due to vitamin A. The combination of 0 IU vitamin A and 500 mg vitamin E/kg diet had the highest values of PCV (40.09%) and hemoglobin (Hb) (10.33 mg/100 mL) among all groups. Vitamin E raised serum values of total protein, total cholesterol and total lipids (P ≤ 0.05 or P ≤ 0.01). Feed intake, FCR, PCV, Hb, lymphocytes, monocytes, eosinophils, T4, ALT and total protein were significantly affected by the interaction of vitamins A and E (P ≤ 0.05 or P ≤ 0.01). The interaction of vitamins A and E was only significant with respect to serum total protein (P ≤ 0.05). It can be concluded that layer diets supplemented with vitamins A and E had good results in alleviating the harmful impacts of high ambient temperature. The combination of 16,000 IU vitamin A and 500 mg vitamin E per kilogram diet is preferable for obtaining better production of laying hens reared under hot summer conditions.
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Impacts of distiller’s dried grains with solubles as replacement of soybean meal plus vitamin E supplementation on production, egg quality and blood chemistry of laying hens. ANNALS OF ANIMAL SCIENCE 2017. [DOI: 10.1515/aoas-2016-0091] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The present investigation aimed to study the effect of the partial replacement of distiller’s dried grains with solubles (DDGS) instead of soybean meal (SBM) with or without vitamin E supplementation in laying hen diet on egg quality criteria, egg analysis, blood chemistry and productive performance traits. A 4×2 factorial design experiment was carried out involving four substitution levels of DDGS (0, 25, 50 and 75%) and two levels of vitamin E (0 and 250 mg /kg diet) through 22-42 weeks of age. No significant differences were noticed between the control and 25 or 50% DDGS substitution in the percentage of eggs produced and egg output. The fewest number of produced eggs and the lightest egg output were observed in 75% DDGS group. Yolk index, shell percentage, and Haugh unit scores were affected (P>0.01) by DDGS levels. Albumin percentage showed increase (P>0.01) in vitamin E treated groups. The impact of the combination of DDGS and vitamin E was significant (P>0.01) on all egg quality traits excepting shell percentage. The 75% DDGS diet gave the highest values of egg nutrients. Vitamin E had a positive effect on egg crude protein, ether extract, and nitrogen free extract which increased by 10.39, 10.28 and 7.85%, respectively. The combination of vitamin E addition and DDGS levels was highly significant (P>0.01) on all egg nutrients. Hens fed the 50% DDGS diet had more concentrations of lipids profile in their blood than those fed control and other DDGS diets. All serum lipid profile inclined to increase due to vitamin E supplementation. The interaction between DDGS and vitamin E had significant (P>0.05 or 0.01) influence on all serum metabolites excepting calcium. It could be concluded that vitamin E could enhance nutrient content of eggs and preserve blood lipids from lipid peroxidation. The interaction between 75% DDGS replaced SBM with 200 mg vitamin E/kg diet accomplished the best results regarding nutrient content of eggs.
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Chicory (Cichorium intybus) Herb: Chemical Composition, Pharmacology, Nutritional and Healthical Applications. INT J PHARMACOL 2017. [DOI: 10.3923/ijp.2017.351.360] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Small optic suspensions for Advanced LIGO input optics and other precision optical experiments. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:114504. [PMID: 27910510 DOI: 10.1063/1.4967716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report on the design and performance of small optic suspensions developed to suppress seismic motion of out-of-cavity optics in the input optics subsystem of the Advanced Laser Interferometer Gravitational Wave Observatory. These compact single stage suspensions provide isolation in all six degrees of freedom of the optic, local sensing and actuation in three of them, and passive damping for the other three.
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Observation of Gravitational Waves from a Binary Black Hole Merger. PHYSICAL REVIEW LETTERS 2016; 116:061102. [PMID: 26918975 DOI: 10.1103/physrevlett.116.061102] [Citation(s) in RCA: 1373] [Impact Index Per Article: 171.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Indexed: 05/04/2023]
Abstract
On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160) Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.
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Drinking water: a major source of lead exposure in Karachi, Pakistan. EASTERN MEDITERRANEAN HEALTH JOURNAL 2012; 17:882-6. [PMID: 22276499 DOI: 10.26719/2011.17.11.882] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Excess lead in drinking water is a neglected source of lead toxicity in Pakistan. A cross-sectional survey in 2007/08 was made of water samples from drinking water sources in Karachi, a large industrial city. This study aimed to compare lead levels between untreated ground water and treated surface (tap) water in 18 different districts. Of 216 ground and surface water samples collected, 86% had lead levels higher than the World Health Organization maximum acceptable concentration of l0 ppb. Mean lead concentration in ground water [146 (SD 119) ppb] was significantly higher than in surface water [77.1 (SD 54) ppb]. None of the 18 districts had a mean lead level of ground or surface water below the WHO cut-off and ground water sources in 9 districts had a severe level of contamination (>150 ppb). Urgent action is needed to eliminate sources of contamination.
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Sonographic fetal biometry charts for a Pakistani cohort. EASTERN MEDITERRANEAN HEALTH JOURNAL 2012; 17:969-75. [PMID: 22355951 DOI: 10.26719/2011.17.12.969] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study aimed to develop growth centiles at different gestational weeks for fetal biparietal diameter, abdominal circumference, femur length and head circumference in a Pakistani cohort. Data were collected at a tertiary referral hospital from pregnant women at gestational ages 13-40 weeks referred for obstetric ultrasound as a part of routine antenatal care. A total of 1599 fetal sonographic biometric measurements were collected after screening for the inclusion criteria. For each measurement, separate regression models were derived to estimate the mean, standard deviation and reference percentiles at each week of gestational age for this cohort. The best fitting model for each variable was selected. These charts will help radiologists and clinicians in predicting dates of delivery, assessing fetal growth and identifying intrauterine fetal insufficiency in the Pakistani population.
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Directional limits on persistent gravitational waves using LIGO S5 science data. PHYSICAL REVIEW LETTERS 2011; 107:271102. [PMID: 22243300 DOI: 10.1103/physrevlett.107.271102] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Indexed: 05/31/2023]
Abstract
The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10(-50) strain(2) Hz(-1) and 5-35×10(-49) strain(2) Hz(-1) sr(-1) for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10(-25) in the most sensitive frequency range near 160 Hz.
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009; 102:111102. [PMID: 19392186 DOI: 10.1103/physrevlett.102.111102] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2008] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009. [PMID: 19392186 DOI: 10.1103/physrevd.80.042003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009. [PMID: 19392186 DOI: 10.1103/physrevd.79.022001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data. PHYSICAL REVIEW LETTERS 2009. [PMID: 19392186 DOI: 10.1103/physrevd.77.022001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.
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Search for gravitational-wave bursts from soft gamma repeaters. PHYSICAL REVIEW LETTERS 2008; 101:211102. [PMID: 19113401 DOI: 10.1103/physrevlett.101.211102] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Indexed: 05/11/2023]
Abstract
We present a LIGO search for short-duration gravitational waves (GWs) associated with soft gamma ray repeater (SGR) bursts. This is the first search sensitive to neutron star f modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10;{45} and 9x10;{52} erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models.
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Modeling the intraurban variability of ambient traffic pollution in Toronto, Canada. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2007; 70:200-12. [PMID: 17365582 DOI: 10.1080/15287390600883018] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The objective of this paper is to model determinants of intraurban variation in ambient concentrations of nitrogen dioxide (NO2) in Toronto, Canada, with a land use regression (LUR) model. Although researchers have conducted similar studies in Europe, this work represents the first attempt in a North American setting to characterize variation in traffic pollution through the LUR method. NO2 samples were collected over 2 wk using duplicate two-sided Ogawa passive diffusion samplers at 95 locations across Toronto. Independent variables employed in subsequent regression models as predictors of NO2 were derived by the Arc 8 geographic information system (GIS). Some 85 indicators of land use, traffic, population density, and physical geography were tested. The final regression model yielded a coefficient of determination (R2) of .69. For the traffic variables, density of 24-h traffic counts and road measures display positive associations. For the land use variables, industrial land use and counts of dwellings within 2000 m of the monitoring location were positively associated with NO2. Locations up to 1500 m downwind of major expressways had elevated NO2 levels. The results suggest that a good predictive surface can be derived for North American cities with the LUR method. The predictive maps from the LUR appear to capture small-area variation in NO2 concentrations. These small-area variations in traffic pollution are probably important to the exposure experience of the population and may detect health effects that would have gone unnoticed with other exposure estimates.
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Abstract
Capillary GC and HPLC of metal chelates of pentamethylene dithiocarbamate were examined. Copper(II), nickel(II), cobalt(III), iron(III), manganese(II) and chromium(III) chelates formed in slightly acidic media (pH 5) were extracted in methyl isobutyl ketone or chloroform. Capillary GC elution and separation was carried out on methylsilicone DB-1 column (25 m x 0.2 mm I.D.) with film thickness 0.25 microm. Electron-capture detection was used. Elution was carried at initial column temperature 200 degrees C with an increment at a rate of 5 degrees C/min up to 250 degrees C and maximum temperature was maintained for 10 min. Symmetrical peaks with baseline separation were obtained with the metal chelates investigated with linear calibration range between 5 and 25 microg/ml for each metal ion and detection limits in the range of 0.5-6.0 microg/ml corresponding to 27-333 pg of metal ion reaching to the detector. HPLC separation was carried out from LiChrosorb ODS, 5 microm column and complexes eluted with methanol-water-1 mM sodium acetate (70:28:2, v/v) with a flow-rate of 1.2 ml/ml. UV detection was at 260 nm. The detection limits obtained were in the range 2-6 microg/ml. The methods were applied to the determination of metal ions in canal water and coal samples with RSD values within 4.15%. The results when compared with a standard flame atomic absorption spectrophotometric method and revealed no significant difference.
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