scholarly journals Local extinctions of obligate frugivores and patch size reduction disrupt the structure of seed dispersal networks

Ecography ◽  
2018 ◽  
Vol 41 (11) ◽  
pp. 1899-1909 ◽  
Author(s):  
Jamille de Assis Bomfim ◽  
Paulo R Guimarães ◽  
Carlos A. Peres ◽  
Gustavo Carvalho ◽  
Eliana Cazetta
Keyword(s):  
Seed Dispersal ◽  
Patch Size ◽  
Size Reduction ◽  
Local Extinctions

scholarly journals Defaunation precipitates the extinction of evolutionarily distinct interactions in the Anthropocene

2019 ◽  
Vol 5 (6) ◽  
pp. eaav6699 ◽  
Author(s):  
Carine Emer ◽  
Mauro Galetti ◽  
Marco A. Pizo ◽  
Pedro Jordano ◽  
Miguel Verdú
Keyword(s):  
Seed Dispersal ◽  
Evolutionary History ◽  
Bird Species ◽  
Forest Fragments ◽  
Ecological Interactions ◽  
Rescue Effect ◽  
History Of ◽  
Local Extinctions ◽  
Functional Features ◽  
Avian Seed Dispersal

Species on Earth are interconnected with each other through ecological interactions. Defaunation can erode those connections, yet we lack evolutionary predictions about the consequences of losing interactions in human-modified ecosystems. We quantified the fate of the evolutionary history of avian–seed dispersal interactions across tropical forest fragments by combining the evolutionary distinctness of the pairwise-partner species, a proxy to their unique functional features. Both large-seeded plant and large-bodied bird species showed the highest evolutionary distinctness. We estimate a loss of 3.5 to 4.7 × 104 million years of cumulative evolutionary history of interactions due to defaunation. Bird-driven local extinctions mainly erode the most evolutionarily distinct interactions. However, the persistence of less evolutionarily distinct bird species in defaunated areas exerts a phylogenetic rescue effect through seed dispersal of evolutionarily distinct plant species.

scholarly journals Critical patch size reduction by heterogeneous diffusion

2020 ◽  
Vol 102 (4) ◽  
Author(s):  
M. A. F. dos Santos ◽  
V. Dornelas ◽  
E. H. Colombo ◽  
C. Anteneodo
Keyword(s):  
Patch Size ◽  
Size Reduction ◽  
Critical Patch Size

scholarly journals Patch size reduction of rectangular microstrip antennas by means of a cuboid ridge

2015 ◽  
Vol 9 (15) ◽  
pp. 1727-1732 ◽  
Author(s):  
Alireza Motevasselian ◽  
William G. Whittow
Keyword(s):  
Patch Size ◽  
Microstrip Antennas ◽  
Size Reduction

Frequency reconfigurable truncated rhombuslike slotted antenna with patch size reduction

2013 ◽  
Author(s):  
S. Muhamud Kayat ◽  
M. T. Ali ◽  
M. K. M. Salleh ◽  
M.H. M. Rusli ◽  
N. Ramli ◽  
...  
Keyword(s):  
Patch Size ◽  
Size Reduction ◽  
Slotted Antenna

scholarly journals Compact Patch MIMO Antenna With Low Mutual Coupling For WLAN Applications

2019 ◽  
Vol 18 (1) ◽  
pp. 43-46
Author(s):  
Murtala Aminu-Baba ◽  
Mohammad Kamal A. Rahim ◽  
Farid Zubir ◽  
Adamu Y. Iliyasu ◽  
Mohd Fairus Mohd Yusoff ◽  
...  
Keyword(s):  
Mutual Coupling ◽  
Patch Size ◽  
Ground Plane ◽  
Size Reduction ◽  
Ring Resonators ◽  
Split Ring ◽  
Split Ring Resonators ◽  
Mimo Antenna ◽  
High Isolation ◽  
Microstrip Patch

A compact triband microstrip patch MIMO antenna is proposed for WLAN applications. The antenna consists of two patches antenna elements, which are orthogonally placed to each other for high isolation at 2.4, 2.8 and 5.8 GHz frequency bands. On its ground plane, a Complementary Split Ring Resonators (CSRRs) is etched for size reduction and multiband generation. The proposed compact MIMO antenna covers an entire size of 58 x 45 x 1.6 mm3, with the patch size of 13.3 x 17.1 mm2. A 79% size reduction at 2.45 GHz was achieved for miniaturization, with a very low mutual coupling (S21 and S12) of -32 dB at all bands.

Habitat fragmentation causes collapse of kelp recruitment

2020 ◽  
Vol 648 ◽  
pp. 111-123
Author(s):  
C Layton ◽  
MJ Cameron ◽  
M Tatsumi ◽  
V Shelamoff ◽  
JT Wright ◽  
...  
Keyword(s):  
Habitat Fragmentation ◽  
Patch Size ◽  
Life Stage ◽  
Extended Period ◽  
Anthropogenic Disturbances ◽  
Anthropogenic Sources ◽  
Kelp Forests ◽  
Natural Disturbances ◽  
Short Term ◽  
Turf Algae

Kelp forests in many regions are experiencing disturbance from anthropogenic sources such as ocean warming, pollution, and overgrazing. Unlike natural disturbances such as storms, anthropogenic disturbances often manifest as press perturbations that cause persistent alterations to the environment. One consequence is that some kelp forests are becoming increasingly sparse and fragmented. We manipulated patch size of the kelp Ecklonia radiata over 24 mo to simulate persistent habitat fragmentation and assessed how this influenced the demography of macro- and microscopic juvenile kelp within the patches. At the beginning of the experiment, patch formation resulted in short-term increases in E. radiata recruitment in patches <1 m2. However, recruitment collapsed in those same patches over the extended period, with no recruits observed after 15 mo. Experimental transplants of microscopic and macroscopic juvenile sporophytes into the patches failed to identify the life stage impacted by the reductions in patch size, indicating that the effects may be subtle and require extended periods to manifest, and/or that another life stage is responsible. Abiotic measurements within the patches indicated that kelp were less able to engineer the sub-canopy environment in smaller patches. In particular, reduced shading of the sub-canopy in smaller patches was associated with proliferation of sediments and turf algae, which potentially contributed to the collapse of recruitment. We demonstrate the consequences of short- and longer-term degradation of E. radiata habitats and conclude that habitat fragmentation can lead to severe disruptions to kelp demography.

Methods for particle size reduction of liposomal amphotericin B

2018 ◽  
Vol 60 (1) ◽  
pp. 42-45
Author(s):  
Tuan Quang Nguyen ◽  
Van Lam Nguyen ◽  
Thai Son Nguyen ◽  
Thi Minh Hue Pham ◽  
◽  
...  
Keyword(s):  
Particle Size ◽  
Amphotericin B ◽  
Liposomal Amphotericin ◽  
Size Reduction ◽  
Liposomal Amphotericin B ◽  
Particle Size Reduction
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