The impact of lunar illumination on narrow-band wide-field surveys

2020 ◽  
Author(s):  
Milena Hygino ◽  
Alessandro Ederoclite ◽  
Héctor Vázquez Ramió ◽  
Jesús Varela ◽  
Andrés Javier Cenarro ◽  
...  
Keyword(s):  
Narrow Band ◽  
Wide Field ◽  
Field Surveys ◽  
The Impact

scholarly journals Blending and obscuration in weak lensing magnification

2021 ◽  
Author(s):  
E Gaztanaga ◽  
S J Schmidt ◽  
M D Schneider ◽  
J A Tyson
Keyword(s):  
Systematic Errors ◽  
Weak Lensing ◽  
Wide Field ◽  
Photometric Redshifts ◽  
Field Surveys ◽  
Systematic Effects ◽  
The Impact ◽  
Close Pairs ◽  
Mass Profiles

Abstract We test the impact of some systematic errors in weak lensing magnification measurements with the COSMOS 30-band photo-z Survey flux limited to Iauto < 25.0 using correlations of both source galaxy counts and magnitudes. Systematic obscuration effects are measured by comparing counts and magnification correlations. We use the ACS-HST catalogs to identify potential blending objects (close pairs) and perform the magnification analyses with and without blended objects. We find that blending effects start to be important (∼ 0.04 mag obscuration) at angular scales smaller than 0.1 arcmin. Extinction and other systematic obscuration effects can be as large as 0.10 mag (U-band) but are typically smaller than 0.02 mag depending on the band. After applying these corrections, we measure a 3.9σ magnification signal that is consistent for both counts and magnitudes. The corresponding projected mass profiles of galaxies at redshift z ≃ 0.6 (MI ≃ −21) is Σ = 25 ± 6M⊙h3/pc2 at 0.1 Mpc/h, consistent with NFW type profile with M200 ≃ 2 × 1012M⊙h/pc2. Tangential shear and flux-size magnification over the same lenses show similar mass profiles. We conclude that magnification from counts and fluxes using photometric redshifts has the potential to provide complementary weak lensing information in future wide field surveys once we carefully take into account systematic effects, such as obscuration and blending.

scholarly journals Testing the evolution of correlations between supermassive black holes and their host galaxies using eight strongly lensed quasars

2020 ◽  
Vol 501 (1) ◽  
pp. 269-280
Author(s):  
Xuheng Ding ◽  
Tommaso Treu ◽  
Simon Birrer ◽  
Adriano Agnello ◽  
Dominique Sluse ◽  
...  
Keyword(s):  
Black Holes ◽  
Hubble Space Telescope ◽  
High Redshift ◽  
Galactic Nuclei ◽  
Host Galaxy ◽  
Wide Field ◽  
Host Galaxies ◽  
Field Surveys ◽  
Instrumental Resolution ◽  
The Moment

ABSTRACT One of the main challenges in using high-redshift active galactic nuclei (AGNs) to study the correlations between the mass of a supermassive black hole ($\mathcal {M}_{\rm BH}$) and the properties of its active host galaxy is instrumental resolution. Strong lensing magnification effectively increases instrumental resolution and thus helps to address this challenge. In this work, we study eight strongly lensed AGNs with deep Hubble Space Telescope imaging, using the lens modelling code lenstronomy to reconstruct the image of the source. Using the reconstructed brightness of the host galaxy, we infer the host galaxy stellar mass based on stellar population models. $\mathcal {M}_{\rm BH}$ are estimated from broad emission lines using standard methods. Our results are in good agreement with recent work based on non-lensed AGNs, demonstrating the potential of using strongly lensed AGNs to extend the study of the correlations to higher redshifts. At the moment, the sample size of lensed AGNs is small and thus they provide mostly a consistency check on systematic errors related to resolution for non-lensed AGNs. However, the number of known lensed AGNs is expected to increase dramatically in the next few years, through dedicated searches in ground- and space-based wide-field surveys, and they may become a key diagnostic of black holes and galaxy co-evolution.

scholarly journals The Impact of Narrow-band Imaging on the Pre- and Intra- operative Assessments of Neoplastic and Preneoplastic Laryngeal Lesions. A Systematic Review

2020 ◽  
Author(s):  
Carmelo Saraniti ◽  
Enzo Chianetta ◽  
Giuseppe Greco ◽  
Norhafiza Mat Lazim ◽  
Barbara Verro
Keyword(s):  
White Light ◽  
Diagnostic Tool ◽  
Narrow Band ◽  
Narrow Band Imaging ◽  
Resection Margins ◽  
Predictive Values ◽  
White Light Endoscopy ◽  
Laryngeal Lesions ◽  
Sensitivity Specificity ◽  
The Impact

Introduction Narrow-band imaging is an endoscopic diagnostic tool that, focusing on superficial vascular changes, is useful to detect suspicious laryngeal lesions, enabling their complete excision with safe and tailored resection margins. Objectives To analyze the applications and benefits of narrow-band imaging in detecting premalignant and malignant laryngeal lesions through a comparison with white-light endoscopy. Data Synthesis A literature search was performed in the PubMed, Scopus and Web of Science databases using strict keywords. Then, two authors independently analyzed the articles, read the titles and abstracts, and read completely only the relevant studies according to certain eligibility criteria. In total, 14 articles have been included in the present review; the sensitivity, specificity, positive and negative predictive values, and accuracy of pre- and/or intraoperative narrow-band imaging were analyzed. The analysis showed that narrow-band imaging is better than white-light endoscopy in terms of sensitivity, specificity, positive and negative predictive values, and accuracy regarding the ability to identify cancer and/or precancerous laryngeal lesions. Moreover, the intraoperative performance of narrow-band imaging resulted more effective than the in-office performance. Conclusion Narrow-band imaging is an effective diagnostic tool to detect premalignant and malignant laryngeal lesions and to define proper resection margins. Moreover, narrow-band imaging is useful in cases of leukoplakia that may cover a possible malignant lesion and that cannot be easily assessed with white-light endoscopy. Finally, a shared, simple and practical classification of laryngeal lesions, such as that of the European Laryngological Society, is required to identify a shared lesion management strategy. Key Points

scholarly journals Impact of the Strong Downwelling (Upwelling) on Small Pelagic Fish Production during the 2016 (2019) Negative (Positive) Indian Ocean Dipole Events in the Eastern Indian Ocean off Java

Climate ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 29
Author(s):  
Jonson Lumban-Gaol ◽  
Eko Siswanto ◽  
Kedarnath Mahapatra ◽  
Nyoman Metta Nyanakumara Natih ◽  
I Wayan Nurjaya ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Indian Ocean Dipole ◽  
Pelagic Fish ◽  
Eastern Indian Ocean ◽  
Fish Production ◽  
Small Pelagic Fish ◽  
Field Surveys ◽  
Chl A ◽  
Positive Indian Ocean Dipole ◽  
The Impact

Although researchers have investigated the impact of Indian Ocean Dipole (IOD) phases on human lives, only a few have examined such impacts on fisheries. In this study, we analyzed the influence of negative (positive) IOD phases on chlorophyll a (Chl-a) concentrations as an indicator of phytoplankton biomass and small pelagic fish production in the eastern Indian Ocean (EIO) off Java. We also conducted field surveys in the EIO off Palabuhanratu Bay at the peak (October) and the end (December) of the 2019 positive IOD phase. Our findings show that the Chl-a concentration had a strong and robust association with the 2016 (2019) negative (positive) IOD phases. The negative (positive) anomalous Chl-a concentration in the EIO off Java associated with the negative (positive) IOD phase induced strong downwelling (upwelling), leading to the preponderant decrease (increase) in small pelagic fish production in the EIO off Java.

scholarly journals Snake charming and the exploitation of snakes in Morocco

Oryx ◽  
2016 ◽  
Vol 52 (2) ◽  
pp. 374-381 ◽  
Author(s):  
Juan M. Pleguezuelos ◽  
Mónica Feriche ◽  
José C. Brito ◽  
Soumía Fahd
Keyword(s):  
Reproductive Output ◽  
Surveys And Questionnaires ◽  
Market Price ◽  
Tourism Industry ◽  
Cultural Dimensions ◽  
Population Declines ◽  
Field Surveys ◽  
Focal Species ◽  
The Impact ◽  
Naja Haje

AbstractTraditional activities that potentially threaten biodiversity represent a challenge to conservationists as they try to reconcile the cultural dimensions of such activities. Quantifying the impact of traditional activities on biodiversity is always helpful for decision making in conservation. In the case of snake charming in Morocco, the practice was introduced there 500 years ago by the religious order the Aissawas, and is now an attraction in the country's growing tourism industry. As a consequence wild snake populations may be threatened by overexploitation. The focal species for snake charming, the Egyptian cobra Naja haje, is undergoing both range and population declines. We estimated the level of exploitation of snakes based on field surveys and questionnaires administered to Aissawas during 2003–2014, and compared our results with those of a study conducted 25 years previously. Aissawas use four venomous and four non-venomous species for snake charming and we estimate they harvest a minimum of 4,500 individuals annually, mostly venomous snakes. For exhibition purposes they selectively remove the largest specimens from the wild (i.e. those that could have the highest reproductive output). Compared to the previous data, we detected (1) a reduction in the number of species collected, (2) an increased distance to collecting fields, and (3) an increase in the market price for snakes, after correction for accumulated inflation, signifying a higher demand for these animals.

scholarly journals Intravitreal Anti-Vascular Endothelial Growth Factor Agents for the Treatment of Diabetic Retinopathy: A Review of the Literature

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1137
Author(s):  
Irini Chatziralli ◽  
Anat Loewenstein
Keyword(s):  
Diabetic Retinopathy ◽  
Vitreous Hemorrhage ◽  
Fundus Photography ◽  
Panretinal Photocoagulation ◽  
Wide Field ◽  
Vascular Endothelial ◽  
Keywords Diabetic Retinopathy ◽  
Anti Vegf ◽  
The Impact

Background: Diabetic retinopathy (DR) is the leading cause of blindness in the working-age population. The purpose of this review is to gather the existing literature regarding the use of the approved anti-vascular endothelial growth (anti-VEGF) agents in the treatment of DR. Methods: A comprehensive literature review in PubMed engine search was performed for articles written in English language up to 1 July 2021, using the keywords “diabetic retinopathy”, “ranibizumab”, “aflibercept”, and “anti-VEGF”. Emphasis was given on pivotal trials and recent robust studies. Results: Intravitreal anti-VEGF agents have been found to significantly improve visual acuity and reduce retinal thickness in patients with diabetic macular edema (DME) in a long-term follow-up ranging from 1 to 5 years and are considered the standard-of-care in such patients. Regarding DR, intravitreal anti-VEGF agents provided ≥2-step improvement in DR severity on color fundus photography in about 30–35% of patients with NPDR at baseline, in the majority of clinical trials originally designed to evaluate the efficacy of intravitreal anti-VEGF agents in patients with DME. Protocol S and CLARITY study have firstly reported that intravitreal anti-VEGF agents are non-inferior to panretinal photocoagulation (PRP) in patients with proliferative DR (PDR). However, the use of new imaging modalities, such as optical coherence tomography-angiography and wide-field fluorescein angiography, reveals conflicting results about the impact of anti-VEGF agents on the regression of retinal non-perfusion in patients with DR. Furthermore, one should consider the high “loss to follow-up” rate and its devastating consequences especially in patients with PDR, when deciding to treat the latter with intravitreal anti-VEGF agents alone compared to PRP. In patients with PDR, combination of treatment of intravitreal anti-VEGF agents and PRP has been also supported. Moreover, in the specific case of vitreous hemorrhage or tractional retinal detachment as complications of PDR, intravitreal anti-VEGF agents have been found to be beneficial as an adjunct to pars plana vitrectomy (PPV), most commonly given 3–7 days before PPV, offering reduction in the recurrence of vitreous hemorrhage. Conclusions: There is no general consensus regarding the use of intravitreal anti-VEGF agents in patients with DR. Although anti-VEGF agents are the gold standard in the treatment of DME and seem to improve DR severity, challenges in their use exist and should be taken into account in the decision of treatment, based on an individualized approach.

scholarly journals REVITALIZATION OF MOUNTAIN RURAL TOURISM AS A TOOL FOR SUSTAINABLE LOCAL DEVELOPMENT IN KABYLIE (ALGERIA). THE CASE OF YAKOUREN MUNICIPALITY

2021 ◽  
Vol 34 (1) ◽  
pp. 112-125
Author(s):  
Amal KELFAOUI ◽  
◽  
Mohamed A. REZZAZ ◽  
Louardi KHERROUR ◽  
◽  
...  
Keyword(s):  
Rural Communities ◽  
Rural Areas ◽  
Swot Analysis ◽  
Local Development ◽  
Rural Tourism ◽  
Mountainous Areas ◽  
Conceptual Approach ◽  
Field Surveys ◽  
The Impact ◽  
Overnight Stays

Our study focuses on the planning and revitalization of mountainous rural tourism to generate income for many rural communities. It targets a community of Great Kabylie in the heart of Djurdjura massif in the eastern part of Tizi-Ouzou province in Algeria. Tourism in these mountainous areas could contribute to rural development, given that it covers 80% of the region and records 13913 tourist overnight stays. Rural tourism can be a valuable tool for local development in the Yakouren municipality. This paper is based on a literature review, field surveys, descriptive and analytical approach to revitalizing mountainous rural tourism in Yakouren, and revealing its potential through various methods, including Butler's theory, SWOT analysis, and elaboration of an indicator grid, and calculation of tourist traffic. From the results, we identified eight segments that attract tourists and five segments that villagers request. Finally, in a conceptual approach, we discuss the impact of this market on rural areas structure and propose some ideas to overcome it. As a result, through constant promotion, Yakouren can benefit from an increase in tourist traffic. Rural tourism in this mountainous community can be an essential source of income, but it requires investment.

scholarly journals Predicting the number of giant arcs expected in the next-generation wide-field surveys from space

2012 ◽  
Vol 427 (4) ◽  
pp. 3134-3144 ◽  
Author(s):  
M. Boldrin ◽  
C. Giocoli ◽  
M. Meneghetti ◽  
L. Moscardini
Keyword(s):  
Wide Field ◽  
Next Generation ◽  
Field Surveys

Innovative Method for Efficient Real Time Online Well Monitoring to Enhance Crew Respond Time in Marginal Field

2021 ◽  
Author(s):  
Dias Anugrah Massewa ◽  
Muhammad Rifaat ◽  
Ferdyan Ihza Akbar ◽  
Rahmanda Fadri ◽  
Denny Mulia Akbar ◽  
...  
Keyword(s):  
Real Time ◽  
Human Error ◽  
Smart Phone ◽  
Wide Field ◽  
C Language ◽  
Measurement Tools ◽  
Production Crew ◽  
Marginal Field ◽  
The Impact ◽  
Smart Phone Application

Abstract Previously, well monitoring in Siak block relied on production crew scheduled tour that needed six hours to complete one cycle of all wells in Lindai field. This paper describes the utilization of digital technology to observe well parameters while sending notification if there is any anomaly regarding those parameters through smart phone application or website. Smart microcontroller was installed in wellhead panel and three sensors are mounted in desired point around wellhead to perform online Intelligent Well Monitoring (IWM) for well’s parameters. If abnormality occurs, real time notification would be sent to user’s smart phone application or website by using global mobile communication system (GSM) signal. The parameters monitored were pressure, temperature, and load because they are essential to be analyzed as initial diagnosis of well problem. Based on the readings, production team could quickly perform troubleshooting to prevent loss production opportunity (LPO). The programming of this smart microcontroller used C language as data compiler. This method was tested in one of the wells in Lindai field, which has the highest oil production. After three months of surveillance, in terms of data quality, the values shown by this tool had only five percent differences compared to manual survey using calibrated measurement tools. Additionally, the parameters could be monitored online, real time, and gave the notification directly to users should there be any issues. Moreover, this tool could reduce the response time of the field crew significantly from six hours following the conventional field tour to only in five minutes by relying on real time notification. In addition, the operational cost of this tool was 82% cheaper compared to other well-known online monitoring tool available in the market so it is considered economical. In the long term, this tool will be implemented on all wells in Siak block for integrated real time monitoring. Furthermore, the impact of field scale implementation will be much greater such as increasing data accuracy by eliminating human error from manual well checking and improving safety of the crew by reducing the possibility of fatigue. The utilization of smart microcontroller for online well monitoring is beneficial for marginal field with high number of wells and wide field coverage. Earlier, real time well monitoring is usually considered expensive investment that rarely become priority. However, the implementation of IoT (Internet of Things) by using this tool can be the game changer in marginal field and maximize the well’s production by reducing LPO.

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