scholarly journals Cranial biomechanics underpins high sauropod diversity in resource-poor environments

2014 ◽  
Vol 281 (1795) ◽  
pp. 20142114 ◽  
Author(s):  
David J. Button ◽  
Emily J. Rayfield ◽  
Paul M. Barrett
Keyword(s):  
Niche Partitioning ◽  
Large Body ◽  
Morrison Formation ◽  
Large Body Size ◽  
Element Analysis ◽  
Terrestrial Vertebrates ◽  
Food Items ◽  
Resource Limited ◽  
Resource Poor ◽  
Insight Into

High megaherbivore species richness is documented in both fossil and contemporary ecosystems despite their high individual energy requirements. An extreme example of this is the Late Jurassic Morrison Formation, which was dominated by sauropod dinosaurs, the largest known terrestrial vertebrates. High sauropod diversity within the resource-limited Morrison is paradoxical, but might be explicable through sophisticated resource partitioning. This hypothesis was tested through finite-element analysis of the crania of the Morrison taxa Camarasaurus and Diplodocus . Results demonstrate divergent specialization, with Camarasaurus capable of exerting and accommodating greater bite forces than Diplodocus , permitting consumption of harder food items. Analysis of craniodental biomechanical characters taken from 35 sauropod taxa demonstrates a functional dichotomy in terms of bite force, cranial robustness and occlusal relationships yielding two polyphyletic functional ‘grades’. Morrison taxa are widely distributed within and between these two morphotypes, reflecting distinctive foraging specializations that formed a biomechanical basis for niche partitioning between them. This partitioning, coupled with benefits associated with large body size, would have enabled the high sauropod diversities present in the Morrison Formation. Further, this provides insight into the mechanisms responsible for supporting the high diversities of large megaherbivores observed in other Mesozoic and Cenozoic communities, particularly those occurring in resource-limited environments.

Planktivorous Baltic Herring (Clupea harengus) Prey Selectively on Reproducing Copepods and Cladocerans

1992 ◽  
Vol 49 (1) ◽  
pp. 73-77 ◽  
Author(s):  
Juha Flinkman ◽  
Ilppo Vuorinen ◽  
Eero Aro
Keyword(s):  
Large Body ◽  
Stomach Contents ◽  
Clupea Harengus ◽  
Large Body Size ◽  
Food Items ◽  
Baltic Herring ◽  
Gulf Of Bothnia ◽  
Baltic Proper ◽  
The Baltic ◽  
Plankton Species

Plankton and Baltic herring (Clupea harengus) were sampled simultaneously at nine sites in the northern Baltic Sea and Gulf of Bothnia. The stomachs from 45 herring and 54 plankton samples were analysed. The prey consisted mainly of adult mesozooplankters: copepods and cladocerans. Larger zooplankters (mysids and amphipods) were very rare in the stomachs as were the younger stages (copepodids) of copepods. The stomach contents of the fish changed from brackish water and neritic plankton species in the northern Baltic Proper to limnic species in the northern part of the Bothnian Sea. The diversity of plankton species decreased along with the salinity from south to north. Comparison of the plankton samples and herring stomach contents showed that prey with a large body size was selected as food. Generally this resulted in female copepods being chosen, since they are larger than males of the same species. Especially preferred food items were species and stages which carried conspicuous egg sacs (Eurytemora affinis females) or pigmented eggs and embryos (Bosmina longispina, Podon spp). Our results suggest that the Baltic herring is capable of exerting a regulative effect on the prey population comparable with that found in freshwater planktivores.

A new species of the subgenus Scheloribates (Topobates) (Acari: Oribatida: Scheloribatidae) from Panama

2020 ◽  
Vol 29 (2) ◽  
pp. 278-283
Author(s):  
S.G. Ermilov
Keyword(s):  
New Species ◽  
Body Size ◽  
Leaf Litter ◽  
Related Species ◽  
Large Body ◽  
Oribatid Mite ◽  
Neotropical Region ◽  
Large Body Size ◽  
First Time ◽  
A New Species

The oribatid mite subgenus Scheloribates (Topobates) Grandjean, 1958, is recorded from the Neotropical region for the first time. A new species of this subgenus is described from the leaf litter collected in Cayo Agua Island, Panama. Scheloribates (Topobates) panamaensis sp. nov. differs from its related species by the very large body size and presence of a strong ventrodistal process on the leg femora II–IV.

scholarly journals Atmospheric Hypoxia Limits Selection for Large Body Size in Insects

PLoS ONE ◽  
2009 ◽  
Vol 4 (1) ◽  
pp. e3876 ◽  
Author(s):  
C. Jaco Klok ◽  
Jon F. Harrison
Keyword(s):  
Body Size ◽  
Large Body ◽  
Large Body Size ◽  
Selection For

Three Turnaround Heat Treating Studies

2003 ◽  
Author(s):  
Jaan Taagepera ◽  
Marty Clift ◽  
D. Mike DeHart ◽  
Keneth Marden
Keyword(s):  
Heat Treatment ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Thermal Stress ◽  
Thermal Stresses ◽  
Heat Treating ◽  
Element Analysis ◽  
Stress Profiles ◽  
Insight Into

Three vessel modifications requiring heat treatment were analyzed prior to and during a planned turnaround at a refinery. One was a thick nozzle that required weld build up. This nozzle had been in hydrogen service and required bake-out to reduce the potential for cracking during the weld build up. Finite element analysis was used to study the thermal stresses involved in the bake-out. Another heat treatment studied was a PWHT of a nozzle replacement. The heat treatment band and temperature were varied with location in order to minimize cost and reduction in remaining strength of the vessel. Again, FEA was used to provide insight into the thermal stress profiles during heat treatment. The fmal heat treatment study was for inserting a new nozzle in a 1-1/4Cr-1/2Mo reactor. While this material would ordinarily require PWHT, the alteration was proposed to be installed without PWHT. Though accepted by the Jurisdiction, this nozzle installation was ultimately cancelled.

scholarly journals New records of ring nematodes, Bakernema enormese n. sp. and Criconema (Nothocriconemella) graminicola Loof, Wouts & Yeates, 1997 (Nematoda: Criconematidae) from natural forests of Vietnam

2019 ◽  
Vol 41 (3) ◽  
Author(s):  
Nguyen Ngoc Chau
Keyword(s):  
New Species ◽  
Body Size ◽  
New Records ◽  
Large Body ◽  
Lateral View ◽  
The Body ◽  
Natural Forests ◽  
Large Body Size ◽  
Stylet Length ◽  
North Vietnam

Bakernema enormese sp. n., collected from rhizosphere of forest wood trees in Muong Phang, Dien Bien Province (north Vietnam) is described and illustrated. The new species is characterized by large body size and stylet. In general, this new species is close to two existing species of the same genus, B. inaequale and B. dauniense by cuticle structure in transparent membranous projections which appear in lateral view as spine-like structures on each annulus. These structure arranged into several rows along the body. In morphology, the new species differs from B. inaequale and B. dauniense  by body and stylet length, i.e. 609–842 µm and 143.5–150 µm vs. 391–578 µm and 59–74 µm for B. inaequale and vs. 391–461 µm and 65–74 µm for B. dauniense. In addition, new species can be distinguished from B. inaequale by the longer membranous projection, 8–12 vs. 6–10 µm and vagina shape, curved vs. sigmoid. From B. dauniense, the new species differs by the much longer membranous projection, 8–12 vs. 1.4–2.2 µm and less number annules between vulva and tail end (RV), 3–4 vs. 7.8 annules. The presence of Criconema (Nothocriconemella) graminicola Loof, Wouts & Yeates, in Vietnam with morphometrics, illustrators and remarks given.

Studies on Temperature Regulation

1946 ◽  
Vol 22 (3-4) ◽  
pp. 213-220
Author(s):  
R. L. KIRK ◽  
LANCELOT HOGBEN
Keyword(s):  
Body Temperature ◽  
Rana Temporaria ◽  
Large Body ◽  
Bufo Bufo ◽  
Thermal Capacity ◽  
The Body ◽  
External Temperature ◽  
Terrestrial Vertebrates ◽  
Temperature And Humidity ◽  
Frog Rana Temporaria

1. The upper thermal death-point of the slow worm (Anguis fragilis) is significantly above that of either the toad (Bufo bufo) or the frog (Rana temporaria). That of the toad differs only slightly from that of the frog. 2. In response to external variation with respect to temperature and humidity, the body temperature of the toad behaves in a manner similar to that of the frog, being considerably below that of the air at low humidities, though appreciably above that of the wet-bulb thermometer. It is concluded that the toad loses water as freely as the frog. 3. The body temperature of the slow worm and that of the alligator (A. mississippiensis) differs only slightly from that of the air under all conditions of sustained air temperature and humidity. 4. The body temperature reaction of the alligator is more sluggish than that of the slow worm, presumably owing to the higher thermal capacity of the animal. 5. The significance of these results in relation to the evolution of the terrestrial vertebrates is discussed. It is suggested that homoeothermic stocks could arise only from reptiles of relatively small size, and that large body size would militate against survival during periods of low mean external temperature.

scholarly journals Should international medical electives to resource-poor countries continue during COVID-19?

2020 ◽  
Vol 27 (6) ◽  
Author(s):  
David McMaster ◽  
Munashe Veremu ◽  
Kpanna M Jonas
Keyword(s):  
Medical Students ◽  
Health Systems ◽  
Healthcare Services ◽  
International Medical ◽  
Poor Countries ◽  
Resource Limited ◽  
Resource Poor ◽  
Voluntary Basis ◽  
Local Healthcare

Medical students on elective offer a workforce that may become essential when local healthcare services in resource-limited countries become overwhelmed. We argue they should not be cancelled, and instead should be offered on a voluntary basis to allow students the opportunity to support struggling health systems during the COVID-19 pandemic.

Exploring hate crime amongst a cohort of Scottish prisoners: an exploratory study

2019 ◽  
Vol 5 (1) ◽  
pp. 39-49
Author(s):  
Kirsty Penrice ◽  
Philip Birch ◽  
Stephan McAlpine
Keyword(s):  
Emotional Regulation ◽  
Hate Crime ◽  
Large Body ◽  
Exploratory Research ◽  
Structured Interviews ◽  
Environmental Implications ◽  
Prison Violence ◽  
Content Type ◽  
Prison Environment ◽  
Insight Into

Purpose The purpose of this paper is to explore the motives a person adopts in order to engage in hate-related behaviours within a prison setting. A subsidiary aim of the study was to compare this cohort of prisoners with prisoners who have been convicted for aggravated racism in the community. Design/methodology/approach In order to gather data, an exploratory research design was adopted, utilising the method of semi-structured interviews. In total, a number of nine interviews were conducted. Qualitative analysis was then employed allowing for an examination of meaning in relation to the motives behind the commission of hate crimes to occur. Findings The findings revealed the presence of racist beliefs and attitudes in both groups involved in the study. Further similarities between the two groups included the perception of inequality and beliefs about racism. The differences between the two groups included poor emotional regulation and an inability to manage beliefs and subsequent behaviours about people from different ethnic groups, with those in custody seeming to be more reactive. Practical implications The findings provide a preliminary insight into enhancing inmate safety. The environmental implications begin to reveal the complexity of hate-related behaviours in custody. There are differences between the context of hate crime committed in a prison environment compared to that committed in the community that require different solutions for addressing such behaviour. Further implications are considered in the final section of the paper. Originality/value A large body of research has been conducted on prison violence, seldom does this research examine this issue within the context of hate crime. This preliminary study offers an insight into prison-based hate crime.

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