scholarly journals The redclaw crayfish: A prominent aquaculture species with invasive potential in tropical and subtropical biodiversity hotspots

2021 ◽  
Author(s):  
Phillip J. Haubrock ◽  
Francisco J. Oficialdegui ◽  
Yiwen Zeng ◽  
Jiří Patoka ◽  
Darren C.J. Yeo ◽  
...  
Author(s):  
Karvita B. Ahluwalia ◽  
Nidhi Sharma

It is common knowledge that apparently similar tumors often show different responses to therapy. This experience has generated the idea that histologically similar tumors could have biologically distinct behaviour. The development of effective therapy therefore, has the explicit challenge of understanding biological behaviour of a tumor. The question is which parameters in a tumor could relate to its biological behaviour ? It is now recognised that the development of malignancy requires an alteration in the program of terminal differentiation in addition to aberrant growth control. In this study therefore, ultrastructural markers that relate to defective terminal differentiation and possibly invasive potential of cells have been identified in human oral leukoplakias, erythroleukoplakias and squamous cell carcinomas of the tongue.


2017 ◽  
Vol 5 (1) ◽  
pp. 58-62 ◽  
Author(s):  
S.T. Lalzarzovi ◽  
◽  
Lalnun Tluanga

Ecological study of tropical semi-evergreen forest of Reiek in Mizoram was carried out to determine the stratification of the forest as well as to prepare life form spectrum of the plant communities. Mizoram is a part of Indo- Myanmar region which falls under one of the 35 biodiversity hotspots identified worldwide and therefore has a rich biodiversity. A detailed floristic survey was carried out. Plant species were collected, mounted in herbarium sheets and identified. Structural analysis was carried out and profile diagram was drawn. The forest was found to be composed of three layers in both the disturbed and undisturbed areas of the forest. The life form spectrum has been compared with Raunkiers normal spectrum to find out the phytoclimate of the region. The study area was found to have an abundance of phanerophytes indicating a phanerophytic climate


Biology ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 420
Author(s):  
Gabriel Biffi ◽  
Simone Policena Rosa ◽  
Robin Kundrata

Jurasaidae are a family of neotenic elateroid beetles which was described recently from the Brazilian Atlantic Forest biodiversity hotspot based on three species in two genera. All life stages live in the soil, including the larviform females, and only adult males are able to fly. Here, we report the discovery of two new species, Jurasai miraculum sp. nov. and J. vanini sp. nov., and a new, morphologically remarkable population of J. digitusdei Rosa et al., 2020. Our discovery sheds further light on the diversity and biogeography of the group. Most species of Jurasaidae are known from the rainforest remnants of the Atlantic Forest, but here for the first time we report a jurasaid species from the relatively drier Atlantic Forest/Caatinga transitional zone. Considering our recent findings, minute body size and cryptic lifestyle of all jurasaids, together with potentially high numbers of yet undescribed species of this family from the Atlantic Forest and possibly also other surrounding ecoregions, we call for both field research in potentially suitable localities as well as for a detailed investigation of a massive amount of already collected but still unprocessed materials deposited in a number of Brazilian institutes, laboratories and collections.


Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1071
Author(s):  
Zuzanna Plichta ◽  
Jarosław Kobak ◽  
Rafał Maciaszek ◽  
Tomasz Kakareko

An ornamental freshwater shrimp, Neocaridina davidi, is popular as an aquarium hobby and, therefore, a potentially invasive species. There is a growing need for proper management of this species to determine not only their optimum breeding conditions, but also their ability to colonise novel environments. We tested habitat preferences of colour morphs (brown, red, white) of N. davidi for substratum colour (black, white, grey shades, red) and fine or coarse chess-board patterns to recognise their suitable captivity conditions and predict their distribution after potential release into nature. We conducted laboratory choice experiments (n = 8) with three individuals of the same morph exposed for two hours to a range of backgrounds. Shrimp preferred dark backgrounds over light ones irrespective of their own colouration and its match with the background colour. Moreover, the brown and red morphs, in contrast to the white morph, preferred the coarse background pattern over the finer pattern. This suggests that the presence of dark, uniform substrata (e.g., rocks, macrophytes) will favour N. davidi. Nevertheless, the polymorphism of the species has little effect on its total niche breadth, and thus its invasive potential.


2021 ◽  
Vol 82 (6) ◽  
Author(s):  
Pawan Kumar ◽  
Jing Li ◽  
Christina Surulescu

AbstractGliomas are primary brain tumors with a high invasive potential and infiltrative spread. Among them, glioblastoma multiforme (GBM) exhibits microvascular hyperplasia and pronounced necrosis triggered by hypoxia. Histological samples showing garland-like hypercellular structures (so-called pseudopalisades) centered around the occlusion site of a capillary are typical for GBM and hint on poor prognosis of patient survival. We propose a multiscale modeling approach in the kinetic theory of active particles framework and deduce by an upscaling process a reaction-diffusion model with repellent pH-taxis. We prove existence of a unique global bounded classical solution for a version of the obtained macroscopic system and investigate the asymptotic behavior of the solution. Moreover, we study two different types of scaling and compare the behavior of the obtained macroscopic PDEs by way of simulations. These show that patterns (not necessarily of Turing type), including pseudopalisades, can be formed for some parameter ranges, in accordance with the tumor grade. This is true when the PDEs are obtained via parabolic scaling (undirected tissue), while no such patterns are observed for the PDEs arising by a hyperbolic limit (directed tissue). This suggests that brain tissue might be undirected - at least as far as glioma migration is concerned. We also investigate two different ways of including cell level descriptions of response to hypoxia and the way they are related .


Diversity ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 122
Author(s):  
Irene Sanchez Gonzalez ◽  
Garrett W. Hopper ◽  
Jamie Bucholz ◽  
Carla L. Atkinson

Biodiversity hotspots can serve as protected areas that aid in species conservation. Long-term monitoring of multiple taxonomic groups within biodiversity hotspots can offer insight into factors influencing their dynamics. Mussels (Bivalvia: Unionidae) and fish are highly diverse and imperiled groups of organisms with contrasting life histories that should influence their response to ecological factors associated with local and global change. Here we use historical and contemporary fish and mussel survey data to assess fish and mussel community changes over a 33 year period (1986–2019) and relationships between mussel abundance and their host fish abundance in Bogue Chitto Creek, a tributary of the Alabama River and a biodiversity hotspot. Mussel abundance declined by ~80% and community composition shifted, with eight species previously recorded not found in 2019, and a single individual of the endangered Pleurobema decisum. Fish abundances increased and life history strategies in the community appeared stable and there was no apparent relationship between mussel declines and abundance of host fish. Temporal variation in the proportion of life history traits composing mussel assemblages was also indicative of the disturbances specifically affecting the mussel community. However, changes and declines in mussel assemblages in Bogue Chitto Creek cannot be firmly attributed to any specific factor or events because of gaps in historical environmental and biological data. We believe that mobility differences contributed to differential responses of fish and mussel communities to stressors including habitat degradation, recent droughts and invasive species. Overall, our work indicates that monitoring biodiversity hotspots using hydrological measurements, standardized survey methods and monitoring invasive species abundance would better identify the effects of multiple and interactive stressors that impact disparate taxonomic groups in freshwater ecosystems.


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