scholarly journals The Saoura Foggaras: Degradation of Hydraulic System Millennium Case of Beni Abbes, Ouakda, Beni Ounif and Lahmar (Algeria)

2017 ◽  
Vol 63 (2) ◽  
pp. 40-47
Author(s):  
Boualem Remini ◽  
Cherrif Rezoug ◽  
Saaed Hamoudi
Keyword(s):  
Hydraulic System ◽  
Unit Volume ◽  
Modern Technology ◽  
First Results ◽  
First Time ◽  
Degraded Condition

AbstractIn this article, we studied, for the first time, the foggaras of Saoura. Five missions were carried out in the oases of Kerzaz, Lahmar, Boukais, Beni Ounif, Ouakda, and Beni Abbes during the years 2009, 2010, 2011, 2012 and 2013. The first results showed that there was a difference between the foggaras of Touat and those of Saoura. The galleries of Saoura are much shorter than those of Touat and Gourara. On the contrary, the distribution of water from the Touat and Gourara foggaras is carried out per unit volume, whereas from the Saoura foggaras per unit time. The foggaras we visited are practically in a degraded condition. The contribution of modern technology (pumps and wells) in the oases of Saoura is the principal cause of the decline of the hydraulic system millennium.

scholarly journals AGN Spectra as Seen by the Infrared Space Observatory: First Results

1997 ◽  
Vol 159 ◽  
pp. 333-336
Author(s):  
D. Lutz ◽  
R. Genzel ◽  
E. Sturm ◽  
A.F.M. Moorwood ◽  
E. Oliva ◽  
...  
Keyword(s):  
Fine Structure ◽  
Short Wavelength ◽  
Molecular Hydrogen ◽  
Molecular Gas ◽  
Space Observatory ◽  
Infrared Space Observatory ◽  
First Results ◽  
External Galaxies ◽  
First Time ◽  
Fine Structure Lines

AbstractWe discuss 2.5–45 µm spectra of the Circinus galaxy and of Cen A, obtained with the Short Wavelength Spectrometer (SWS) on board the Infrared Space Observatory. The large number of detected ionic fine structure lines, observable also in visually obscured sources, provides strong constraints on the shape of the ionizing spectrum, which is found to exhibit a UV bump peaking at ~ 70 eV in the case of Circinus. Pure rotational emission of molecular hydrogen, directly probing warm molecular gas, can for the first time be detected in external galaxies.

scholarly journals Intra-Day Variability Observations of Two Dozens of Blazars at 4.8 GHz

Universe ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 15
Author(s):  
Xiang Liu ◽  
Xin Wang ◽  
Ning Chang ◽  
Jun Liu ◽  
Lang Cui ◽  
...  
Keyword(s):  
Active Galactic Nuclei ◽  
Galactic Nuclei ◽  
Forthcoming Paper ◽  
Galactic Latitude ◽  
Local Interstellar Medium ◽  
Bl Lac Objects ◽  
Spectrum Radio ◽  
First Results ◽  
First Time ◽  
Source Structure

Two dozens of radio loud active galactic nuclei (AGNs) have been observed with Urumqi 25 m radio telescope in order to search for intra-day variability (IDV). The target sources are blazars (namely flat spectrum radio quasars and BL Lac objects) which are mostly selected from the observing list of RadioAstron AGN monitoring campaigns. The observations were carried out at 4.8 GHz in two sessions of 8–12 February 2014 and 7–9 March respectively. We report the data reduction and the first results of observations. The results show that the majority of the blazars exhibit IDV in 99.9% confidence level, some of them show quite strong IDV. We find the strong IDV of blazar 1357 + 769 for the first time. The IDV at centimeter-wavelength is believed to be predominately caused by the scintillation of blazar emission through the local interstellar medium in a few hundreds parsecs away from Sun. No significant correlation between the IDV strength and either redshift or Galactic latitude is found in our sample. The IDV timescale along with source structure and brightness temperature analysis will be presented in a forthcoming paper.

First Results from the VULCAN Diffractometer at the SNS

2010 ◽  
Vol 652 ◽  
pp. 105-110 ◽  
Author(s):  
X.L. Wang ◽  
Thomas Holden ◽  
A.D. Stoica ◽  
K. An ◽  
H.D. Skorpenske ◽  
...  
Keyword(s):  
Neutron Beam ◽  
Research Opportunities ◽  
Instrument Performance ◽  
Measurement Results ◽  
First Results ◽  
Design Calculations ◽  
New Research ◽  
First Time

On Friday June 26, 2009, the neutron beam shutter for the VULCAN diffractometer at the SNS was opened for the first time. Initial measurements to characterize the instrument performance are reported. It is shown that the measurement results are by and large in agreement with design calculations. New research opportunities with VULCAN are discussed.

scholarly journals First Results from Insemination With Sex-Sorted Semen in Dairy Heifers in Macedonia

2015 ◽  
Vol 38 (1) ◽  
pp. 107-111
Author(s):  
Ljupche Kochoski ◽  
Zoran Filipov ◽  
Ilcho Joshevski ◽  
Stevche Ilievski ◽  
Filip Davkov
Keyword(s):  
Pregnancy Rate ◽  
Transrectal Ultrasound ◽  
Gestation Length ◽  
Dairy Heifers ◽  
Holstein Friesian ◽  
First Results ◽  
Long Time ◽  
The Usa ◽  
Normal Gestation ◽  
First Time

Abstract Science has been searching for a long time for a reliable method for controlling the sex of mammalian offspring. Recently, the application of specific modern cellular methodologies has led to the development of a flow cytometric system capable of differentiating and separating living X- and Y-chromosome-bearing sperm cells in amounts suitable for AI and therefore, commercialization of this sexing technology. The aim of this work was to present the first results of heifers that introduce bovine AI with sex sorted semen, for the first time in Macedonia. Insemination with sex sorted cryopreserved semen (2×106 spermatozoa per dose) imported from the USA was done at two dairy farms in ZK Pelagonija. In total, 74 heifers (Holstein Friesian) were inseminated. Inseminations were carried out in a timely manner following a modified OvSynch protocol. During the insemination, the sperm was deposited into the uterine horn ipsi lateral to the ovary where a follicle larger than 1.6 cm was detected by means of transrectal ultrasound examination. Pregnancy was checked by ultrasound on day 30 after the insemination. Overall, the average pregnancy rate in both farms was 43,24% (40,54% and 45,95%, for farm 1 and farm 2, respectively). All pregnant heifers delivered their calves following a normal gestation length (274,3 days in average) and of the 32 born calves, 30 (93,75%) were female. In conclusion, since the first results from inseminations with sex-sorted semen in dairy heifers in Macedonia are very promising, the introduction of this technique may bring much benefit to the local dairy sector. Average pregnancy rate seems similar with results obtained following ‘regular’ inseminations, notwithstanding the relatively low number of spermatozoa per insemination dose. Due to the latter, we however recommend inseminations only to be carried out by experienced technicians followinga TAI protocol and ultrasound examinations of the ovaries prior to insemination.

scholarly journals THE FIRST DATA ON THE MEIOBENTHOS OF LAKE NERO

2020 ◽  
pp. 61-72
Author(s):  
V. Gusakov
Keyword(s):  
Species Richness ◽  
Aquatic Organisms ◽  
Quantitative Structure ◽  
Community Members ◽  
Volga River ◽  
Volga River Basin ◽  
Qualitative And Quantitative ◽  
First Results ◽  
High Species Richness ◽  
First Time

The paper provides the first results of a study of the qualitative and quantitative structure of the community of bottom meiofauna (meiobenthos) in shallow, hypereutrophic Lake Nero (Volga River basin, Yaroslavl region, Russia). In the samples, collected in early September 2017, 106 representatives from 16 systematic groups of aquatic organisms were found. About half of them had not been previously recorded in the lake's fauna. The species composition of Gastrotricha, Nematoda, Tardigrada, Acari, Harpacticoida, and Ostracoda was analyzed in the water body for the first time. It is established that at the end of the vegetation season, the lake's meiobenthos characterizes by relatively high species richness, diversity, and quantitative parameters. The circle of the main (dominant) community members in the studied period was outlined.

scholarly journals Cepheids in the Nearby Galaxy IC 1613

2000 ◽  
Vol 176 ◽  
pp. 157-160
Author(s):  
E. Antonello ◽  
L. Mantegazza ◽  
D. Fugazza ◽  
M. Bossi ◽  
S. Covino
Keyword(s):  
Magellanic Clouds ◽  
Light Curves ◽  
Nearby Galaxy ◽  
Short Discussion ◽  
The Galaxy ◽  
First Results ◽  
First Time

AbstractA summary of the first results of a search for Cepheids in IC 1613 is reported along with a short discussion of the adopted technique, a comparison of the characteristics of Cepheid light curves in the Galaxy, Magellanic Clouds and IC 1613, and a possible application for a P–L relation derivation. First overtone Cepheids have been identified for the first time in a galaxy farther than the Magellanic Clouds.

scholarly journals The Thousand-Pulsar-Array programme on MeerKAT – I. Science objectives and first results

2020 ◽  
Vol 493 (3) ◽  
pp. 3608-3615 ◽  
Author(s):  
Simon Johnston ◽  
A Karastergiou ◽  
M J Keith ◽  
X Song ◽  
P Weltevrede ◽  
...  
Keyword(s):  
Radio Emission ◽  
Single Pulse ◽  
Wide Band ◽  
Radio Pulsars ◽  
Pulse Trains ◽  
First Results ◽  
Dispersion Measures ◽  
Large Survey ◽  
First Time

ABSTRACT We report here on initial results from the Thousand-Pulsar-Array (TPA) programme, part of the Large Survey Project ‘MeerTime’ on the MeerKAT telescope. The interferometer is used in the tied-array mode in the band from 856 to 1712 MHz, and the wide band coupled with the large collecting area and low receiver temperature make it an excellent telescope for the study of radio pulsars. The TPA is a 5 year project, which aims at to observing (a) more than 1000 pulsars to obtain high-fidelity pulse profiles, (b) some 500 of these pulsars over multiple epochs, and (c) long sequences of single-pulse trains from several hundred pulsars. The scientific outcomes from the programme will include the determination of pulsar geometries, the location of the radio emission within the pulsar magnetosphere, the connection between the magnetosphere and the crust and core of the star, tighter constraints on the nature of the radio emission itself, as well as interstellar medium studies. First, results presented here include updated dispersion measures, 26 pulsars with Faraday rotation measures derived for the first time, and a description of interesting emission phenomena observed thus far.

scholarly journals Probing the Redshift Desert Using the Gemini Deep Deep Survey: Observing Galaxy Mass Assembly at z > 1

2005 ◽  
Vol 216 ◽  
pp. 390-397
Author(s):  
Karl Glazebrook ◽  
Keyword(s):  
Spectroscopic Studies ◽  
Star Forming ◽  
Hubble Sequence ◽  
First Results ◽  
Deep Survey ◽  
Redshift Survey ◽  
Mass Assembly ◽  
Galaxy Assembly ◽  
First Time ◽  
The Universe

The aim of the Gemini Deep Deep Survey is to push spectroscopic studies of complete galaxy samples (both red and blue objects) significantly beyond z = 1; this is the redshift where the current Hubble sequence of ellipticals and spirals is already extant. In the Universe at z = 2 the only currently spectroscopically confirmed galaxies are blue, star-forming and of fragmented morphology. Exploring this transition means filling the ‘redshift desert’ 1 < z < 2 where there is a dearth of spectroscopic measurements. To do this we need to secure redshifts of the oldest, reddest galaxies (candidate ellipticals) beyond z > 1 which has led us to carry out the longest exposure redshift survey ever done: 100 ksec spectroscopic MOS exposures with GMOS on Gemini North. We have developed an implementation of the CCD “nod & shuffle” technique to ensure precise sky-subtraction in these ultra-deep exposures. At the halfway mark the GDDS now has ∼ 36 galaxies in the redshift desert 1.2 < z < 2 extending up to z = 1.97 and I < 24.5 with secure redshifts based on weak rest-frame UV absorption features complete for both red, old objects and young, blue objects. The peak epoch of galaxy assembly is now being probed by direct spectroscopic investigation for the first time. on behalf of the GDDS team I present our first results on the properties of galaxies in the ‘redshift desert’.

scholarly journals Debris Disk Science with the Palomar ExAO System: First Results

2013 ◽  
Vol 8 (S299) ◽  
pp. 72-73 ◽  
Author(s):  
Matthew Wahl ◽  
Stanimir Metchev ◽  
Rahul Patel ◽  
Eugene Serabyn ◽  
Dimitri Mawet ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Scattered Light ◽  
Outer Ring ◽  
Imaging Results ◽  
First Results ◽  
Debris Disk ◽  
First Time ◽  
Adaptive Optics System

AbstractWe present first imaging results from the PALM-3000 adaptive optics system and PHARO camera on the Hale 5 m telescope. Observations using a vector vortex coronagraph have given us direct detections of the two-ring dusty debris system around the star HD 141569. Our observations reveal the inner clearing in the disk to unprecedentedly small angular separations, and are the most sensitive yet at the H and K bands. We are for the first time able to measure and compare the colors of the scattered light in the inner and outer dust rings, and find that the outer ring is significantly bluer than the inner ring.

scholarly journals Optimisation of confinement in a fusion reactor using a nonlinear turbulence model

2018 ◽  
Vol 84 (2) ◽  
Author(s):  
E. G. Highcock ◽  
N. R. Mandell ◽  
M. Barnes ◽  
W. Dorland
Keyword(s):  
First Principles ◽  
Figure Of Merit ◽  
Large Scale ◽  
Unit Volume ◽  
Fusion Reactor ◽  
Small Scale ◽  
Zonal Flows ◽  
Novel Approach ◽  
First Time ◽  
Turbulent Cascade

The confinement of heat in the core of a magnetic fusion reactor is optimised using a multidimensional optimisation algorithm. For the first time in such a study, the loss of heat due to turbulence is modelled at every stage using first-principles nonlinear simulations which accurately capture the turbulent cascade and large-scale zonal flows. The simulations utilise a novel approach, with gyrofluid treatment of the small-scale drift waves and gyrokinetic treatment of the large-scale zonal flows. A simple near-circular equilibrium with standard parameters is chosen as the initial condition. The figure of merit, fusion power per unit volume, is calculated, and then two control parameters, the elongation and triangularity of the outer flux surface, are varied, with the algorithm seeking to optimise the chosen figure of merit. A twofold increase in the plasma power per unit volume is achieved by moving to higher elongation and strongly negative triangularity.

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