scholarly journals Spatiotemporal Dynamics and Geodetic Mass Changes of Glaciers With Varying Debris Cover in the Pangong Region of Trans-Himalayan Ladakh, India Between 1990 and 2019

2021 ◽  
Vol 9 ◽  
Author(s):  
Ulfat Majeed ◽  
Irfan Rashid ◽  
Nadeem Ahmad Najar ◽  
Nafeeza Gul
Keyword(s):  
Remote Sensing Data ◽  
Western Himalaya ◽  
Infrastructure Development ◽  
Glacier Recession ◽  
Digital Elevation ◽  
Debris Cover ◽  
Glacial Lake Outburst Flood ◽  
The Impact

Glaciers across the Himalayan arc are showing varying signs of recession. Glaciers in the eastern and western parts of the Himalayan arc are retreating more rapidly as compared to other regions. This differential retreat is often attributed to climatic, topographic, and geologic influences. The glaciers in the Trans-Himalayan region of Ladakh are believed to be relatively stable as compared to other parts of the western Himalaya. The present study ascertained the area changes and frontal retreat of 87 glaciers in the Pangong Region between 1990 and 2019 using satellite data. The geodetic mass changes were also assessed using SRTM and TanDEM-X digital elevation models of 2000 and 2012 respectively. Besides, the glacier outlines were delineated manually and compared with existing regional and global glacier inventories that are available over the region. The GlabTop model was used to simulate the glacier-bed overdeepenings of four glaciers that are associated with a proglacial lake. The study also analyzed the impact of topographic influences and varying debris cover on glacier recession. This analysis indicated deglaciation of 6.7 ± 0.1% (0.23% a−1) from 1990 to 2019 over the Pangong Region with clean-ice glaciers showing a higher retreat (8.4 ± 0.28%) compared to the debris-covered glaciers (5.7 ± 0.14%). However, the overall recession is lower compared to other parts of northwestern Himalayas. The glacier recession showed a positive correlation with mean glacier slope (r = 0.3) and debris cover (r = 0.1) with bigger size glaciers having retreated at a lesser pace compared to smaller ones. This underpins the need for in-situ data about debris thickness to precisely ascertain the role of debris on glacier recession in the Trans-Himalayan Ladakh where debris thickness data is absent. The mean glacier elevation did not indicate any influence on glacier recession. From 2000 to 12, the glaciers lost an ice mass amounting to 0.33 ± 0.05 m we. per year. The formation of four new proglacial lakes, although small (<6 ha), need to be monitored using remote sensing data while the infrastructure development activities should not be permitted given glacial lake outburst flood risk.

scholarly journals Preoperative breast magnetic resonance imaging in patients with ductal carcinoma in situ: a systematic review for the European Commission Initiative on Breast Cancer (ECIBC)

2021 ◽  
Author(s):  
Carlos Canelo-Aybar ◽  
Alvaro Taype-Rondan ◽  
Jessica Hanae Zafra-Tanaka ◽  
David Rigau ◽  
Axel Graewingholt ◽  
...  
Keyword(s):  
Ductal Carcinoma In Situ ◽  
Surgical Outcomes ◽  
Carcinoma In Situ ◽  
Ductal Carcinoma ◽  
Breast Conserving Surgery ◽  
Cochrane Library ◽  
Treatment Change ◽  
The Impact

Abstract Objective To evaluate the impact of preoperative MRI in the management of Ductal carcinoma in situ (DCIS). Methods We searched the PubMed, EMBASE and Cochrane Library databases to identify randomised clinical trials (RCTs) or cohort studies assessing the impact of preoperative breast MRI in surgical outcomes, treatment change or loco-regional recurrence. We provided pooled estimates for odds ratios (OR), relative risks (RR) and proportions and assessed the certainty of the evidence using the GRADE approach. Results We included 3 RCTs and 23 observational cohorts, corresponding to 20,415 patients. For initial breast-conserving surgery (BCS), the RCTs showed that MRI may result in little to no difference (RR 0.95, 95% CI 0.90 to 1.00) (low certainty); observational studies showed that MRI may have no difference in the odds of re-operation after BCS (OR 0.96; 95% CI 0.36 to 2.61) (low certainty); and uncertain evidence from RCTs suggests little to no difference with respect to total mastectomy rate (RR 0.91; 95% CI 0.65 to 1.27) (very low certainty). We also found that MRI may change the initial treatment plans in 17% (95% CI 12 to 24%) of cases, but with little to no effect on locoregional recurrence (aHR = 1.18; 95% CI 0.79 to 1.76) (very low certainty). Conclusion We found evidence of low to very low certainty which may suggest there is no improvement of surgical outcomes with pre-operative MRI assessment of women with DCIS lesions. There is a need for large rigorously conducted RCTs to evaluate the role of preoperative MRI in this population. Key Points • Evidence of low to very low certainty may suggest there is no improvement in surgical outcomes with pre-operative MRI. • There is a need for large rigorously conducted RCTs evaluating the role of preoperative MRI to improve treatment planning for DCIS.

The Risk of Water Erosion on the Foothills of the Middle High Atlas (Morocco): Tagueleft Basin Case Study : خطر التعرية المائية على السفوح بالأطلس الكبير الأوسط (المغرب): دراسة حالة حوض تاكلفت

2020 ◽  
Vol 4 (3) ◽  
Author(s):  
Rizki Mohamed
Keyword(s):  
Land Degradation ◽  
Local Development ◽  
Remote Sensing Data ◽  
Potential Method ◽  
Water Erosion ◽  
High Atlas ◽  
Negative Impacts ◽  
The Impact

The Tagueleft basin is geographically located in the northern edges of the Middle High Atlas, which is a geomorphological fragile area. The impact of human activity has accelerated water erosion in this mountains area. This is reflected in dynamic and unstable foothills, a decrease in forests density and degradation in the production of the land. On the other hand, land degradation due to human overexploitation of natural resources has increased land degradation in the area. The interest in the risk of erosion on the foothills in the area under study comes in the context of our contribution to clarify the role of geomatical and geomorphological approaches in explaining and identifying the mechanisms responsible for current foothills dynamism through water erosion and its negative impacts on the environment and local development. The aim of the study was to use the EPM (Erosion Potential Méthod) which is formulated by Slobodan Gavrilovic for erosion in mountainous areas and to test the reliability of its results based on fieldwork and remote sensing data. The results of the erosion assessment and its quantification by applying the coefficient (W) for the theoretical model in the area under study have shown that erosion is very important and it touches on wide areas as it appears through the domain classification of the distribution erosion in Tagueleft basin.

Glacier recession and glacial lake outburst flood studies in Zanskar basin, western Himalaya

2018 ◽  
Vol 564 ◽  
pp. 376-396 ◽  
Author(s):  
Riyaz Ahmad Mir ◽  
Sanjay K. Jain ◽  
A.K. Lohani ◽  
Arun K. Saraf
Keyword(s):  
Western Himalaya ◽  
Glacial Lake ◽  
Outburst Flood ◽  
Glacier Recession ◽  
Glacial Lake Outburst Flood

Impact of Mobile the Wireless Technologies on Developing Countries

2011 ◽  
pp. 96-116
Author(s):  
Ran Neuman ◽  
P.C. Deans
Keyword(s):  
Developing Countries ◽  
Economic Benefits ◽  
Infrastructure Development ◽  
Low Literacy ◽  
Wireless Technologies ◽  
Business Opportunity ◽  
Technological Advances ◽  
The Impact ◽  
The Village

This chapter discusses the impact of mobile and wireless technologies on developing countries. The new technological advances and capabilities allow developing countries the opportunity to “leapfrog” years of wired technology and infrastructure development. Based on this study, it appears that mobile and wireless technologies will not be enough to truly advance developing countries. In order to truly “leapfrog” and make up for years of technological advancements, developing countries must consider dealing with government corruption, violation of human rights and extremely low literacy rates. All those factors will derail the effort to “leapfrog” and gain economic benefits from technological advancements. The Village Cell Phone Program is an example where mobile technology created a business opportunity while at the same time changing the role of women in society. Any implementation of mobile and wireless technology must be complemented with social and political reform in order to be successful.

scholarly journals Debris cover and the thinning of Kennicott Glacier, Alaska, Part A:in situ mass balance measurements

2019 ◽  
Author(s):  
Leif S. Anderson ◽  
Robert S. Anderson ◽  
Pascal Buri ◽  
William H. Armstrong
Keyword(s):  
Mass Balance ◽  
High Mountain ◽  
Glacier Surface ◽  
Ice Dynamics ◽  
Air Temperatures ◽  
High Resolution Imagery ◽  
Debris Cover ◽  
The Alps

Abstract. The mass balance of many Alaskan glaciers is perturbed by debris cover. Yet the effect of debris on glacier response to climate change in Alaska has largely been overlooked. In three companion papers we assess the role of debris, ice dynamics, and surface processes in thinning Kennicott Glacier. In Part A, we report in situ measurements from the glacier surface. In Part B, we develop a method to delineate ice cliffs using high-resolution imagery and produce distributed mass balance estimates. In Part C we explore feedbacks that contribute to glacier thinning. Here in Part A, we describe data collected in the summer of 2011. We measured debris thickness (109 locations), sub-debris melt (74), and ice cliff backwasting (60) data from the debris-covered tongue. We also measured air-temperature (3 locations) and internal-debris temperature (10). The mean debris thermal conductivity was 1.06 W (m C)−1, increasing non-linearly with debris thickness. Mean debris thicknesses increase toward the terminus and margin where surface velocities are low. Despite the relatively high air temperatures above thick debris, the melt-insulating effect of debris dominates. Sub-debris melt rates ranged from 6.5 cm d−1 where debris is thin to 1.25 cm d−1 where debris is thick near the terminus. Ice cliff backwasting rates varied from 3 to 14 cm d−1 with a mean of 7.1 cm d−1 and tended to increase as elevation declined and debris thickness increased. Ice cliff backwasting rates are similar to those measured on debris-covered glaciers in High Mountain Asia and the Alps.

scholarly journals Four decades of glacier variations at Muztag Ata (Eastern Pamir): a multi-sensor study including Hexagon KH-9 and Pléiades data

2015 ◽  
Vol 9 (2) ◽  
pp. 1811-1856 ◽  
Author(s):  
N. Holzer ◽  
S. Vijay ◽  
T. Yao ◽  
B. Xu ◽  
M. Buchroithner ◽  
...  
Keyword(s):  
Distal Part ◽  
Remote Sensing Data ◽  
Mass Gain ◽  
Temporal Variations ◽  
Surface Velocity ◽  
Low Velocity ◽  
Average Mass ◽  
Digital Elevation ◽  
Landsat 7

Abstract. Recent mass balance measurements indicate a slight mass gain at Muztag Ata in the Eastern Pamir. We extend these measurements both in space and time by using remote sensing data and present four decades of glacier variations in the entire mountain massif. Geodetic mass-balances and area changes were determined at glacier scale from stereo satellite imagery and derived Digital Elevation Models (DEMs). This includes Hexagon KH-9 (year 1973), ALOS-PRISM (2009), Pléiades (2013) and Landsat 7 ETM+ data in conjunction with the SRTM-3 DEM (2000). In addition, surface velocities of Kekesayi Glacier, the largest glacier at Muztag Ata, were derived from TerraSAR-X amplitude tracking. Locally, we observed strong spatial and temporal variations during the last four decades, which were, however, on average not significant for the entire massif. Some south-west exposed glaciers fluctuated or advanced, while glaciers with other aspects rather experienced continuous shrinkage. Several glaciers such as Kekesayi indicate no visual change at their frontal position, but clear down-wasting despite mostly thick debris coverage at low altitudes. The surface velocity of this largest debris-covered glacier of the massif reach up to 20 cm per day, but its distal part of the tongue appears to be stagnant. The low velocity or even stagnancy at the tongue is likely one reason for the down-wasting. On average, the glaciers showed a small, insignificant shrinkage from 274.3 ± 10.6 km2 in 1973 to 272.7 ± 1.0 km2 in 2013 (−0.02 ± 0.1% a−1). Average mass changes in the range of −0.03 ± 0.33 m w.e. a−1 (1973–2009) to −0.01 ± 0.30 m w.e. a−1 (1973–2013) reveal nearly balanced budgets for the last forty years. Indications of slightly positive trends after 1999 (+0.04 ± 0.27 m w.e. a−1) are confirmed by in-situ measurements.

scholarly journals Frail Males on the American Frontier: The Role of Environmental Harshness on Sex Ratios at Birth across a Period of Rapid Industrialization

2021 ◽  
Vol 10 (9) ◽  
pp. 319
Author(s):  
Ryan Schacht ◽  
Mike Hollingshaus ◽  
Heidi Hanson ◽  
Shane J. Macfarlan ◽  
Douglas Tharp ◽  
...  
Keyword(s):  
Sex Ratios ◽  
Early 20Th Century ◽  
Infrastructure Development ◽  
Social Variables ◽  
American Frontier ◽  
The Us ◽  
Rapid Industrialization ◽  
The Impact ◽  
Shed Light

While sex ratios at birth (SRB) have been shown to vary within and across populations, after over a century of research, explanations have remained elusive. A variety of ecological, demographic, economic, and social variables have been evaluated, yet their association with SRB has been equivocal. Here, in an attempt to shed light on this unresolved topic within the literature, we approach the question of what drives variation in SRB using detailed longitudinal data spanning the frontier-era to the early 20th century in a population from the US state of Utah. Using several measures of environmental harshness, we find that fewer boys are born during challenging times. However, these results hold only for the frontier-era and not into a period of rapid economic and infrastructure development. We argue that the mixed state of the literature may result from the impact and frequency of exogenous stressors being dampened due to industrialization.

scholarly journals The Role of Payments for Emissions of Pollutants From Associated Petroleum Gas Flaring as a Tool for Regulating the Rational Use of Natural Resources in the Oil-Producing Regions of the Russian Federation

2020 ◽  
pp. 198-214
Author(s):  
Irina A. Makarova ◽  
Keyword(s):  
Russian Federation ◽  
Raw Materials ◽  
Import Substitution ◽  
Infrastructure Development ◽  
Repair Work ◽  
Associated Petroleum Gas ◽  
Rational Use ◽  
The Russian Federation ◽  
The Impact

For a long time, Russia was the leader in associated petroleum gas (APG) flaring. This led to the destruction of useful raw materials and environmental pollution. Due to the tightening of the state policy in the field of the APG rational use and the introduction of fees for APG flaring in 2012, oil producing companies had an incentive to use APG efficiently. In addition, the level of air pollution began to decline. The budgets of the constituent entities of the Russian Federation in the oil-producing regions began to receive significant revenues. Some experts expected that the APG efficiency target would be achieved in 2014 or 2016. Unfortunately, some oil producers were unable to achieve the target. Moreover, at present, there is a reduction in payments for APG flaring in many regions. This causes concern for certain market participants. The object of this research is the impact of APG flaring fees on the level of rational APG use and on incomes of the oil-producing regions. The aim of the work is to study the role of these payments as a tool for regulating the rational use of APG. The analysis shows that the introduction of fees for emissions of pollutants generated by APG flaring plays an important role in ensuring the sustainable development of the regions. Firstly, this fee helps to improve the environmental situation in the region because the volume of gas flared has decreased significantly. Secondly, the application of fees for APG flaring contributes to an increase in the level of energy efficiency, the development and implementation of innovative technologies. Thirdly, the increase in APG deep processing makes it possible to obtain products required in the domestic industry. This improves the efficiency of the oil sector and accelerates import substitution. Fourthly, payments for emissions of pollutants generated during APG flaring form additional funds that can be spent on the development of the region. Fifthly, all oil-producing regions can be divided into two groups. The first group is a group that has practically reached or is very close to reaching the established limits for APG flaring. The second group of regions is a group for which reaching this target is still a difficult task. Experts point out the following reasons that prevent some oil-producing companies from achieving targets for APG flaring: (1) commissioning of new fields, which are characterized by an insufficient level of infrastructure development required for APG utilization; (2) closure of gas processing plants for repair work, which forces some companies to temporarily flare APG; (3) establishment of new benefits and exemptions; (4) geographic fragmentation of fields and limited reserves, which does not allow making the project for the rational use of APG profitable; (5) remoteness of some gas pipelines from the main oil-producing regions, difficult access to the gas transportation system.

scholarly journals Sensitivity of geodetic glacier mass balance estimation to DEM void interpolation

2018 ◽  
Author(s):  
Robert McNabb ◽  
Christopher Nuth ◽  
Andreas Kääb ◽  
Luc Girod
Keyword(s):  
Mass Balance ◽  
Terrestrial Ecosystems ◽  
Glacier Mass Balance ◽  
Direct Impact ◽  
Glacier Surface ◽  
Southeast Alaska ◽  
Digital Elevation ◽  
Regional Basis ◽  
The Impact

Abstract. Glacier mass balance is a direct expression of climate change, with implications for sea level, ocean chemistry, oceanic and terrestrial ecosystems, and water resources. Traditionally, glacier mass balance has been estimated using in-situ measurements of changes in surface height and density at select locations on the glacier surface, or by comparing changes in surface height using repeat, full-coverage digital elevation models (DEMs), also called the geodetic method. DEMs often have gaps in coverage (voids) based on the nature of the sensor used and the surface being measured. The way that these voids are accounted for has a direct impact on the estimate of geodetic glacier mass balance, though a systematic comparison of different proposed methods has been heretofore lacking. In this study, we determine the impact and sensitivity of void-filling methods on estimates of volume change. Using two spatially complete, high-resolution DEMs over Southeast Alaska, USA, we compare 11 different void-filling methods on a glacier-by-glacier and regional basis. We find that a few methods introduce biases of up to 20 % in the regional results, while other methods give results very close (

scholarly journals Isolating the Role of the Node-Linker Bond in the Compression of UiO-66 Metal-Organic Frameworks

2020 ◽  
Author(s):  
Louis Redfern ◽  
Maxime Ducamp ◽  
Megan C. Wasson ◽  
Lee Robison ◽  
Florencia Son ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Density Functional ◽  
Metal Organic Frameworks ◽  
Coordination Bond ◽  
Metal Organic ◽  
Dft Simulations ◽  
The Impact ◽  
Organic Linker

Understanding the mechanical properties of metal–organic frameworks (MOFs) is essential to the fundamental advancement and practical implementations of porous materials. Recent computational and experimental efforts have revealed correlations between mechanical properties and pore size, topology, and defect density. These results demonstrate the important role of the organic linker in the response of these materials to physical stresses. However, the impact of the coordination bond between the inorganic node and organic linker on the mechanical stability of MOFs has not been thoroughly studied. Here, we isolate the role of this node–linker coordination bond to systematically study the effect it plays in the compression of a series of isostructural MOFs, M-UiO-66 (M = Zr, Hf, or Ce). The bulk modulus (i.e. the resistance to compression under hydrostatic pressure) of each MOF is determined by in situ diamond anvil cell (DAC) powder X-ray diffraction measurements and density functional theory (DFT) simulations. These experiments reveal distinctive behavior of Ce-UiO-66 in response to pressures under one GPa. In situ DAC Raman spectroscopy and DFT calculations support the observed differences in compressibility between Zr-UiO-66 and the Ce- analogue. Monitoring changes in bond lengths as a function of pressure through DFT simulations provides a clear picture of those which shorten more drastically under pressure and those which resist compression. This study demonstrates that changes to the node–linker bond can have significant ramifications on the mechanical properties of MOFs.

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