Spatio-Temporal Shift of Right Bank of the Gumti River, Amarpur Town, Tripura and Its Impact

Author(s):  
Sima Majumdar ◽  
Nibedita Das
2008 ◽  
Vol 36 (3) ◽  
pp. 289-297 ◽  
Author(s):  
Jayanta K. Pati ◽  
Jyoti Lal ◽  
K. Prakash ◽  
R. Bhusan

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ana I. Sousa ◽  
José Figueiredo da Silva ◽  
Ana Azevedo ◽  
Ana I. Lillebø

Abstract This work assessed the Blue Carbon (C) stock in the seagrass meadows (Zostera noltei) of Ria de Aveiro coastal lagoon (Portugal), and evaluated its spatio-temporal trend over the 2003–2005 to 2013–2014 period. Zostera noltei spatial distribution, restricted to intertidal areas in 2014, was mapped by remote sensing using an unmanned aerial vehicle (UAV) and aerial photography. Zostera noltei biomass was also monitored in situ over a year and its Blue C stock was estimated. By 2014, intertidal meadows covered an area of 226 ± 4 ha and their Blue C stock ranged from 227 ± 6 to 453 ± 13 Mg C. Overall, Ria de Aveiro Z. noltei intertidal meadows increased in extent over the 2003–2005 to 2013–2014 period, corroborating the recent declining trend reversal observed in Europe and contrary to the global decline trend. This spatio-temporal shift might be related to a natural adjustment of the intertidal meadows to past human intervention in Ria de Aveiro, namely large-scale dredging activities, particularly in the 1996–1998 period, combined with the more accurate assessment performed in 2014 using the UAV. This recovery contributes to the effective increase of the Blue C stock in Ria de Aveiro and, ultimately, to supporting climate regulation and improving ecosystem health. However, major dredging activities are foreseen in the system’s management plan, which can again endanger the recovery trend of Z. noltei intertidal meadows in Ria de Aveiro.


2020 ◽  
Author(s):  
Jan J. Kreider ◽  
Anna Nehrkorn ◽  
Svenja Bänsch ◽  
Carmen Kirsch ◽  
Catrin Westphal

AbstractIntensified agriculture increasingly threatens wild and managed bees by promoting landscape uniformity and reducing floral resource availability whereas urban areas can provide continuous floral resources within green spaces and private gardens. Mass-flowering events of crops and trees, such as lime trees (Tilia spp.), can provide ample floral resources but only for short time periods. Using waggle dance decoding, pollen analysis and bee abundance recordings, we investigated the temporal shift in honeybee foraging behaviour in response to lime tree mass-flowering. Honeybees in urban areas extended their foraging range during lime tree flowering. Foraging behaviour of honeybees in rural areas did not change to such an extent and honeybees foraged in sown flower strips. Our results suggest that honeybees optimize their foraging behaviour to exploit highly rewarding resources instead of extending foraging ranges in times of floral resource scarcity.


2021 ◽  
pp. 147035722096672
Author(s):  
Nashwa Elyamany

Military-themed videogames are significant cultural artifacts that shape popular geopolitical narratives and venerate dominant post-9/11 War on Terror discourses. Overwhelmingly resonant with the Military Entertainment Complex, these artifacts, not excluding America’s Army (2002–2013), envision the world through a Western lens. Over the past decades, America’s Army has come to challenge dominant orthodoxies and ideological presuppositions, disseminating new configurations of power. The article argues that the latest installment of the game, America’s Army: Proving Grounds (2013), marks a paradigmatic shift from the post-9/11 discourse permeating most military-themed videogames. Taking past scholarship on geopolitics and multimodal legitimation as points of departure, the current study unfolds the militarized aesthetics and politics of gameplay unique to America’s Army: Proving Grounds in its capacity to promote redefined ideals of hegemonic masculinity, on the one hand, and substantiate US universal legitimacy, on the other. To this end, the research endeavor proposes a more nuanced multimodal legitimation analytical framework in an attempt to capture the full spectrum of the semiotic affordances instilled in the gaming space. Key convergent discourses and practices of hegemony emerge therein, fundamentally: proficiency, efficiency, virtuosity, agility, nobility, solidarity, precision, stoicism, and aggression. The spatio-temporal shift away from post-9/11 discourses reifies new militaristic representations of hegemonic masculinity symbiotically entangled with futuristic and non-contemporary ideological war narratives.


2011 ◽  
Vol 140 (1) ◽  
pp. 91-99 ◽  
Author(s):  
W. J. ALONSO ◽  
R. ACUÑA-SOTO ◽  
R. GIGLIO ◽  
J. NUCKOLS ◽  
S. LEYK ◽  
...  

SUMMARYDiarrhoeal mortality rates in Mexican children dramatically declined during the 1980s and 1990s, concomitant with a temporal shift in peak deaths from summer to autumn–winter. The spatial dynamics of these patterns have not previously been studied. We first describe the seasonal features of paediatric diarrhoeal mortality in Mexico as a whole, then across individual states. While no geographical gradients in the magnitude of diarrhoeal mortality rates have been detected in recent years, we identified a distinct spatial pattern in the timing of peak mortality rate. In the 1980s the summer peak mortality was earliest around Mexico's capital and later in states to the southeast and northwest. Our results suggest that the direction and timing of those annual waves are related to the mean monthly precipitation and mean daily temperature. This pattern has disintegrated in recent years as the summer peak has diminished.


2005 ◽  
Vol 41 ◽  
pp. 15-30 ◽  
Author(s):  
Helen C. Ardley ◽  
Philip A. Robinson

The selectivity of the ubiquitin–26 S proteasome system (UPS) for a particular substrate protein relies on the interaction between a ubiquitin-conjugating enzyme (E2, of which a cell contains relatively few) and a ubiquitin–protein ligase (E3, of which there are possibly hundreds). Post-translational modifications of the protein substrate, such as phosphorylation or hydroxylation, are often required prior to its selection. In this way, the precise spatio-temporal targeting and degradation of a given substrate can be achieved. The E3s are a large, diverse group of proteins, characterized by one of several defining motifs. These include a HECT (homologous to E6-associated protein C-terminus), RING (really interesting new gene) or U-box (a modified RING motif without the full complement of Zn2+-binding ligands) domain. Whereas HECT E3s have a direct role in catalysis during ubiquitination, RING and U-box E3s facilitate protein ubiquitination. These latter two E3 types act as adaptor-like molecules. They bring an E2 and a substrate into sufficiently close proximity to promote the substrate's ubiquitination. Although many RING-type E3s, such as MDM2 (murine double minute clone 2 oncoprotein) and c-Cbl, can apparently act alone, others are found as components of much larger multi-protein complexes, such as the anaphase-promoting complex. Taken together, these multifaceted properties and interactions enable E3s to provide a powerful, and specific, mechanism for protein clearance within all cells of eukaryotic organisms. The importance of E3s is highlighted by the number of normal cellular processes they regulate, and the number of diseases associated with their loss of function or inappropriate targeting.


2019 ◽  
Vol 47 (6) ◽  
pp. 1733-1747 ◽  
Author(s):  
Christina Klausen ◽  
Fabian Kaiser ◽  
Birthe Stüven ◽  
Jan N. Hansen ◽  
Dagmar Wachten

The second messenger 3′,5′-cyclic nucleoside adenosine monophosphate (cAMP) plays a key role in signal transduction across prokaryotes and eukaryotes. Cyclic AMP signaling is compartmentalized into microdomains to fulfil specific functions. To define the function of cAMP within these microdomains, signaling needs to be analyzed with spatio-temporal precision. To this end, optogenetic approaches and genetically encoded fluorescent biosensors are particularly well suited. Synthesis and hydrolysis of cAMP can be directly manipulated by photoactivated adenylyl cyclases (PACs) and light-regulated phosphodiesterases (PDEs), respectively. In addition, many biosensors have been designed to spatially and temporarily resolve cAMP dynamics in the cell. This review provides an overview about optogenetic tools and biosensors to shed light on the subcellular organization of cAMP signaling.


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