Intraspecific gastropod shell strength variation among north temperate lakes

1999 ◽  
Vol 56 (9) ◽  
pp. 1687-1695 ◽  
Author(s):  
David Bruce Lewis ◽  
John J Magnuson
Keyword(s):  
Freshwater Snail ◽  
The Body ◽  
Feeding Time ◽  
Strength Increase ◽  
Resource Depression ◽  
North Central ◽  
Helisoma Anceps ◽  
Predator Abundance ◽  
North Temperate Lakes ◽  
Slow Growing

Defensive morphological traits may vary intraspecifically. Freshwater snail shells are conspicuous defensive structures. In north-central Wisconsin, we investigate whether among-lake differences in shell strength relate to water chemistry or predator abundance and whether shell strength is inducible owing to predation risk from crayfish. Amnicola limosa shells were stronger in lakes with abundant crayfish predators. An experiment and a general understanding of prosobranch evolution suggest that this may result from selection rather than induction. The experiment indicated a weakening of shells of slow-growing A. limosa in the presence of crayfish. This may have resulted from resource depression caused by a strong behavioral response that reduced feeding time. Physa skinneri shell strength was correlated with lake calcium concentrations, and a weak trend with calcium was apparent for Helisoma anceps. Decreased P. skinneri shell strength in low-calcium lakes may result from retention of scarce calcium by the body at the expense of allocation to the shell. Populations of H. anceps differed in rates of shell strength increase with body size, suggesting that rates of shell strength accumulation with ontogeny vary among populations. Shell strength increased more rapidly in lakes with abundant predators than in lakes with few predators.

Self Healing of Epoxy Composite for Aircraft's Structural Applications

2008 ◽  
Vol 136 ◽  
pp. 39-44 ◽  
Author(s):  
Willy C.K. Tan ◽  
J.C. Kiew ◽  
K.Y. Siow ◽  
Z.R. Sim ◽  
H.S. Poh ◽  
...  
Keyword(s):  
Composite Structures ◽  
Polymeric Materials ◽  
Hollow Fibre ◽  
The Body ◽  
Strength Increase ◽  
Self Healing ◽  
Structural Applications ◽  
Self Repair ◽  
Repair Systems ◽  
Point Bend

When one cut himself, it's amazing to watch how quickly the body acts to mend the wound. Immediately, the body works to pull the skin around the cut back together. The concept of repair by bleeding of enclosed functional agents serves as the biomimetric inspiration of synthetic self repair systems. Such synthetic self repair systems are based on advancement in polymeric materials; the process of human thrombosis is the inspiration for the application of self healing fibres within the composite materials. Preliminary results based on flexural 3 point bend test on prepared samples have shown the healed hollow fibre laminate has a healed strength increase of 47.6% compared to the damaged baseline laminate. These results gave us confidence that there is a great potential to adopt such self healing mechanism on actual composite parts like in aircraft’s composite structures.

Requirement of Metabolizable Energy for Slow-Growing Yellow-Feathered Male Chickens

2019 ◽  
Author(s):  
Khaled Abouelezz ◽  
Yibing Wang ◽  
Weiwei Wang ◽  
Xiajing Lin ◽  
Long Li ◽  
...  
Keyword(s):  
Control Level ◽  
The Body ◽  
Metabolizable Energy ◽  
Breast Muscle ◽  
Plasma Metabolites ◽  
Final Body Weight ◽  
Quadratic Response ◽  
Metabolizable Energy Intake ◽  
Dose Response Study ◽  
Slow Growing

A dose-response study was conducted to investigate the metabolizable energy (ME) requirement for Lingnan chickens from 57 to 105 days of age. 1200 57-d-old slow-growing yellow-feathered male chickens were allotted to five dietary ME levels (2,805, 2,897, 2,997, 3,095 and 3,236 kcal/kg). The 2,997 kcal/kg treatment was considered to be the control level. The results revealed that the daily metabolizable energy intake increased (P < 0.01), whereas the feed intake and feed: gain ratio decreased linearly (P < 0.01) with the increment in dietary ME level. The final body weight and daily gain of the highest ME treatment tended (P > 0.05) to be greater than those obtained with the lower ME levels. The fat content in breast muscle showed a quadratic response (P < 0.05) to the increase of dietary energy level. The shear force values of breast muscle in the 2,897, 3,095 and 3,236 kcal/kg treatments were lower (P < 0.05) than that of the control. Other results were obtained regarding the body composition, meat quality, and plasma metabolites. In conclusion, the dietary ME level 3,236 kcal/kg can be recommended as the optimal ME requirement for slow-growing yellow-feathered male chickens between 57 and 105 d of age.

scholarly journals Age relative height, weight and body mass index percentiles of children in Jos, North-Central Nigeria

2021 ◽  
Vol 12 (8) ◽  
pp. 149-154
Author(s):  
Ovayoza O. Mosugu ◽  
Francis Shinku ◽  
Jacob C. Nyam ◽  
Emmanuel S. Mador
Keyword(s):  
Body Mass Index ◽  
Childhood Obesity ◽  
Body Mass ◽  
Weight Status ◽  
Body Height ◽  
Mean Value ◽  
The Body ◽  
Healthy Weight ◽  
North Central ◽  
The Mean

Background: Interpretation of body mass index in children is quite different from that in adults which use standard weight status categories that are the same for all ages and for both men and women. Aims and Objective: The study was aimed at determining the prevalence of childhood obesity in Jos. Materials and Methods: A total of 371 children were enrolled in the study. Weight was taken with only light clothing and without foot wears. Height obtained without head-gears or shoes and the measuring flat tops pressed down to avoid errors due to tall hair. Body mass index were calculated for each subject as ratio of body weight to body height. All data were analyzed statistically and separately for different ages and the mean values for height against age, weight against age, height against weight and BMI for age was obtained with centiles of absolute deviations from the mean. Results: The age of the studied population ranged from 3 – 14 years with mean of 8.4 ± 2.8. Height of the children on the other hand ranged from 0.9 – 1.64 meters with mean value of 1.26 ± 0.15 and their weight ranged from 10 – 76 kg with mean value of 25.6 ± 9.2. Out of the 371 children studied, 14 (3.8%) were found to be underweight, 302 (81.4%) had healthy weight while 41 (11%) were at risk of overweight and 14 (3.8%) were overweight. In addition, the body mass index of girls was found to be significantly higher than those of boys at 12 and 13 years only. Conclusion: It is concluded that the prevalence of childhood obesity is high in Jos, North-central Nigeria.

scholarly journals The value of dermoscopy in the diagnosis of epidermal cyst

2021 ◽  
Vol 12 (e) ◽  
pp. 1-2
Author(s):  
Samia Mrabat ◽  
Zakia Douhi ◽  
Chaymae Jroundi
Keyword(s):  
Correct Diagnosis ◽  
The Body ◽  
Epidermal Cyst ◽  
Epithelial Cyst ◽  
Skin Tumour ◽  
The Face ◽  
Slow Growing

Epidermal cyst also called epithelial cyst is a very common benign skin tumour. They can appear anywhere on the body but are most common on the face, neck and trunk. They are slow growing and often painless. It is usually easy to diagnose. Sometimes, it can be difficult to make a correct diagnosis for non-typical cases such as multiple, small lesions or those lacking a central comedo-like punctum. We here report the case of an epidermal cyst with no clinically visible punctum in which the dermoscopy was very helpful.

Tuberculosis

2019 ◽  
Author(s):  
Jonathan B. Parr ◽  
Michael K Leonard Jr ◽  
Henry M Blumberg
Keyword(s):  
Latent Tuberculosis Infection ◽  
Extrapulmonary Tuberculosis ◽  
Latent Tuberculosis ◽  
Acid Fast Bacillus ◽  
The Body ◽  
Cell Mediated Immunity ◽  
Bacterial Disease ◽  
Key Words Tuberculosis ◽  
Droplet Nuclei ◽  
Slow Growing

Tuberculosis (TB) is a bacterial disease caused by Mycobacterium tuberculosis, a relatively slow-growing, aerobic, acid-fast bacillus (AFB). Classically, TB is a pulmonary disease, but disseminated and extrapulmonary manifestations may also occur, especially in immunocompromised persons. TB is transmitted person to person and is usually contracted by inhalation of M. tuberculosis droplet nuclei generated by an infectious person. If infection occurs after M. tuberculosis enters the body, the host’s cell-mediated immunity may contain the organism but not eradicate all the bacilli, resulting in latent tuberculosis infection (LTBI). M. tuberculosis can remain dormant and persist (e.g., within macrophages); persons with LTBI are at risk for reactivation and development of active TB. This review contains 5 figures, 7 tables, and 75 references. Key Words: tuberculosis, pulmonary tuberculosis, extrapulmonary tuberculosis, tuberculosis in hiv-infected patients

Early Greek Vases from Crete

1931 ◽  
Vol 31 ◽  
pp. 56-114 ◽  
Author(s):  
M. Hartley
Keyword(s):  
The Body ◽  
Small Ring ◽  
North Central ◽  
Light Yellow ◽  
Greek Vases ◽  
The Hill ◽  
Narrow Bands

Most of the vases and fragments here published are from North Central Crete—Episkopi and Arkhanes in the province of Pedhiadha, Fortezza and Kephala near Knossos, various parts of the Palace and Little Palace at Knossos; a few pieces are added from Eleutherna, further west.The Fortezza vases were found by Mr. Payne in 1927 in an almost completely destroyed chamber tomb of the type described in B.S.A. xxix. p. 226, Fig. 2, in the side of the hill about a mile from Knossos. They are of the protogeometric, geometric, and orientalising periods.The type is found in some numbers at Knossos, Fortezza, Anopolis and Episkopi; there is an example in Candia Museum from Kavousi, the only specimen from Eastern Crete; the shape does not occur anywhere in the protogeometric period. In these pithoi from Fortezza, the clay varies from light yellow to buff and brown, the varnish is black, the decoration is arranged in panels; the lower part of the body is decorated with broad and narrow bands; there is a small ring foot.

scholarly journals Giant lipomas of the upper extremity

2007 ◽  
Vol 15 (3) ◽  
pp. 141-144 ◽  
Author(s):  
Brian Allen ◽  
Christine Rader ◽  
Alan Babigian
Keyword(s):  
Soft Tissue ◽  
Upper Extremity ◽  
The Body ◽  
Upper Extremities ◽  
Review Of The Literature ◽  
Soft Tissue Tumours ◽  
Slow Growing

Lipomas are slow-growing soft tissue tumours that rarely reach a size larger than 2 cm. Lesions larger than 5 cm, so-called giant lipomas, can occur anywhere in the body but are seldom found in the upper extremities. The authors present their experiences with eight patients having giant lipomas of the upper extremity. In addition, a review of the literature, and a discussion of the appropriate evaluation and management are included.

Culture characteristics and variation of Cronartium flaccidum isolates

1996 ◽  
Vol 74 (6) ◽  
pp. 924-933 ◽  
Author(s):  
S. Moricca ◽  
A. Ragazzi
Keyword(s):  
Host Species ◽  
Pinus Halepensis ◽  
Cultural Variation ◽  
Rust Disease ◽  
North Central ◽  
Culture Characteristics ◽  
Microscopic Features ◽  
Pinus Laricio ◽  
Slow Growing

Cultures of Cronartium flaccidum were established from aeciospores collected from Pinus halepensis and Pinus laricio growing at four Italian sites: one southern and one northern (north-central) site for each host species. The two southern and the two northern sites were also geographically separate. Colonies were incubated for 7 months and compared for growth rates, macroscopic and microscopic features of the colonies, presence or absence of sporulation, and spore type. Germ tubes exhibited negative geotropism and were light sensitive. Colonies from southern isolates generally remained white and fast growing throughout, whereas colonies from northern isolates tended to turn orange and become slow growing. The faster growing white colonies could be maintained in the same Petri dishes without undergoing morphological change for the entire incubation period, but the slow-growing orange colonies had to be transferred to fresh medium every month or they became covered with short, hyaline hyphae. Immature aeciospores, typical mature aeciospores, and teliospore-like bodies formed in culture. Spore ontogeny, capacity to be successfully subcultured, growth rate, and other evidence indicated the southern and north-central Italian isolates were distinct. The host species was not a factor in culture variation. The importance of the axenic technique in relation to rust disease research is discussed. Keywords: rust, in vitro growth, cultural variation, sporulation.

scholarly journals Impacts of Graded Levels of Metabolizable Energy on Growth Performance and Carcass Characteristics of Slow-Growing Yellow-Feathered Male Chickens

Animals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 461 ◽  
Author(s):  
K. F. M. Abouelezz ◽  
Y. Wang ◽  
W. Wang ◽  
X. Lin ◽  
L. Li ◽  
...  
Keyword(s):  
Body Weight ◽  
Feed Intake ◽  
Shear Force ◽  
The Body ◽  
Metabolizable Energy ◽  
Breast Muscle ◽  
Feed Conversion ◽  
Final Body Weight ◽  
Metabolizable Energy Intake ◽  
Slow Growing

A dose-response study was conducted to investigate the metabolizable energy (ME) requirement for Lingnan chickens from 9 to 15 weeks of age. One thousand two hundred 8-week-old slow-growing yellow-feathered male chickens were allotted to five dietary ME levels (2805, 2897, 2997, 3095 and 3236 kcal/kg). The results revealed that the daily metabolizable energy intake increased (p < 0.01), whereas the feed intake and feed:gain ratio decreased linearly (p < 0.01) with the increment in dietary ME level. The final body weight and daily gain of the highest ME treatment tended (p > 0.05) to be greater than those obtained with the lower ME levels. The fat content in breast muscle showed a quadratic response (p < 0.05) to the increase in dietary energy level. The shear force values of breast muscle in the 2897, 3095 and 3236 kcal/kg treatments were lower (p < 0.05) than those of the 2997 kcal/kg treatment. In conclusion, among the tested ME levels, 3095 kcal/kg was adequate for feed intake, shear force, and plasma uric acid, and 3236 kcal/kg tended to increase the body weight, body gain, and feed conversion ratio of Lingnan males between 9 and 15 weeks of age; further studies are still required for testing higher levels.

scholarly journals Gut bacterial communities in the freshwater snail Planorbella trivolvis and their modification by a non-herbivorous diet

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10716
Author(s):  
Zongfu Hu ◽  
Qing Tong ◽  
Jie Chang ◽  
Jianhua Yu ◽  
Shuguo Li ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Intestinal Microbiota ◽  
Bacterial Communities ◽  
Plant Biomass ◽  
Diversity Index ◽  
Freshwater Snail ◽  
The Body ◽  
Water Tank ◽  
Significant Difference ◽  
Planorbella Trivolvis

The freshwater pulmonate snail Planorbella trivolvis is a common species in various bodies of water but is not native to China. Planorbella trivolvis usually live on diets with high fiber content, such as water grasses, algae and fallen leaves. These snails can attach to the wall of a water tank or to water grass and can be transported overseas to China through the ornamental fish trade. There are few studies investigating the intestinal microbiota of freshwater snails. In this study, using culture-independent molecular analysis, we assessed for the first time the complexity of bacterial communities in the intestines of reared snails. The intestinal microbiota in the snails fed different diets, that is, herbivorous feed (HV) with high cellulose and non-herbivorous feed (NHV) with low cellulose, were analyzed by Illumina sequencing. The results showed that the NHV-based diet significantly increased the body mass, shell diameter and specific growth rate of the snails after 60 days of rearing (P < 0.05). Histological experiments showed that the fat droplets in the epithelium columnar cells of the intestines of the NHV snails increased, and the cilia on these cells fell off. The sequencing results identified 486 and 195 OTUs in HV and NHV, respectively. Lots of bacteria were not reported previously in snails. The intestinal microbiota diversity index (Shannon, Simpson, Ace and Chao) in the NHV snails was significantly lower than that in the HV snails. The gut microbiota in the HV snails were predominantly Proteobacteria (52.97%) and Bacteroidetes (28.75%), while the gut microbiota in NHV snails were predominantly Proteobacteria (95.23%). At the genus level, Cloacibacterium (24.60%), Pseudomonas (4.47%), OM6ON (6.12%), and Rhodobacter (5.79%) were observed to be abundant in HV snails. However, Aeromonas (85.4%) was determined to be predominant in NHV snails. Functional prediction of the gut microbiome in snails by PICRUSt demonstrated a significant difference between the two groups, and the HV snails exhibited higher lignocellulose enzyme activity than did the NHV snails. This study represents a first step in characterizing the gut microbiota of the freshwater snail. Most of these microbes can process plant biomass and digest cellulose and lignocellulose, and the enzymes of these bacteria may have potential biotechnological applications in a variety of industrial processes.

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