The respiratory importance of vascularization of the tadpole operculum in Rana catesbeiana Shaw

1969 ◽  
Vol 47 (6) ◽  
pp. 1239-1243 ◽  
Author(s):  
Norman Gradwell
Keyword(s):  
Surface Area ◽  
Respiratory Function ◽  
Rana Catesbeiana ◽  
Bullfrog Tadpole ◽  
Anuran Tadpole ◽  
First Time ◽  
Arteries And Veins

Capillary densities in the opercular membrane of the bullfrog tadpole are consistent with the postulate that this membrane has the respiratory function of increasing the surface area for blood ventilation. The arteries and veins of the opercular membrane are mapped and identified for the first time in an anuran tadpole.

Gill irrigation in Rana catesbeiana. Part I. On the anatomical basis

1972 ◽  
Vol 50 (5) ◽  
pp. 481-499 ◽  
Author(s):  
Norman Gradwell
Keyword(s):  
Epithelial Cells ◽  
Muscle Fiber ◽  
Rana Catesbeiana ◽  
Muscle Fibers ◽  
Functional Studies ◽  
Anatomical Basis ◽  
Different Types ◽  
The Difference ◽  
Anuran Tadpole ◽  
First Time

The gross and histological anatomy of the gill irrigation apparatus are discussed. Two histologically different types of muscle fiber are identified in certain muscles by virtue of the difference in the proportion of fibrillar to sarcoplasmic material in the muscle fibers. An accessory jaw tendon, the valve of the first gill cleft, and several ligaments are described for the first time in an anuran tadpole. An opercular muscle and a fascia lateralis are also described for the first time in a ranid tadpole. The rugulose lining of the pharynx is well vascularized; attention is also drawn to epithelial cells whose points project into the lumen of the pharynx. Several discrepancies in the literature on tadpole anatomy are discussed. To facilitate functional studies, an alphanumeric terminology is proposed for the branchiomeric muscles.

scholarly journals Regularities of Variation of the Red Blood Indices Characterizing the Respiratory Function of Blood in Selected Fish

2011 ◽  
Vol 56 (1-4) ◽  
pp. 35-48 ◽  
Author(s):  
Sebastian Maciak ◽  
Alina Kostelecka-Myrcha
Keyword(s):  
Surface Area ◽  
Oxygen Transport ◽  
Respiratory Function ◽  
Hemoglobin Concentration ◽  
Total Surface Area ◽  
Great Variability ◽  
Blood Indices ◽  
Erythrocyte Surface ◽  
Area Unit ◽  
Counter Current

Regularities of Variation of the Red Blood Indices Characterizing the Respiratory Function of Blood in Selected FishThere is a large diversity of red blood indices determining oxygen transport ability in vertebrates. In fish this diversity is particularly large, probably due to the great variability in water environments, which impedes the possibility of finding and understanding general patterns. It has been assumed that in mammals, the measure determining the ability of a blood unit to transport oxygen is the ratio of hemoglobin concentration (HB) and total erythrocyte surface area (TSAE). It was also shown that both in mammals and birds the amount of hemoglobin per total surface area unit (Hb/TSAE) conditions maximum use of respiratory pigment in oxygen transport, in different physiological and environmental conditions. In order to check whether this regularity occurs in fish, red blood indices were analyzed in seven species of freshwater fish, differing noticeably in their biology and body mass in two seasons of the year. Notwithstanding this marked seasonal variability to the component variables together determining the total surface area of erythrocytes, the value for TSAE was found to differ in proportion to the higher or lower concentrations of HB. In consequence, the HB/TSAE ratio indicative of the maximal use of haemoglobin in the transport of oxygen was constant in all of the fish studied between analyzed seasons. This constancy - resembling that to be noted in birds - is most probably related to the counter-current gaseous exchange ongoing in the gills of fish.

A new distribution record and the reproductive strategy of Pomatoschistus pictus adriaticus (Pisces: Gobiidae) in the Mediterranean Sea

2003 ◽  
Vol 83 (5) ◽  
pp. 1157-1161 ◽  
Author(s):  
Jean-Luc Bouchereau ◽  
Virginie Houder ◽  
Adam Marques ◽  
José E. Rebelo
Keyword(s):  
Mediterranean Sea ◽  
Surface Area ◽  
Reproductive Strategy ◽  
Nest Size ◽  
Gulf Of Lions ◽  
Larval Length ◽  
Egg Diameter ◽  
First Time ◽  
Distribution Record ◽  
New Distribution

Specimens and nests of Pomatoschistus pictus adriaticus have been caught for the first time along the French Mediterranean shore (Gulf of Lions). Six types of nests are found on sandy-gravelly bottom at 10 m depth and 25.3 to 27.5 g 1−1 salinity, using in 84.7% of cases, a valve of Cardium edule (3.3≤weight g≤40.6; 507≤surface mm2≤2490). Nest size, egg patch, surface area and nesting fecundity are positively correlated. Nesting fecundity varies between 669 and 4690 eggs. For a similar egg diameter, the egg height is less than that of P. minutus which spawns on the same bottom and localities. Larval length at hatching varies from 1.70 to 2.67 mm.

scholarly journals Protective effect of exogenous hydrogen sulfide on diaphragm muscle fibrosis in streptozotocin-induced diabetic rats

2020 ◽  
Vol 245 (14) ◽  
pp. 1280-1289
Author(s):  
Rui Yang ◽  
Qiang Jia ◽  
Yan Li ◽  
Shomaila Mehmood
Keyword(s):  
Diabetes Mellitus ◽  
Skeletal Muscle ◽  
Hydrogen Sulfide ◽  
Nlrp3 Inflammasome ◽  
Respiratory Function ◽  
Diaphragm Muscle ◽  
Receptor Protein ◽  
Muscle Fibrosis ◽  
First Time ◽  
Oligomerization Domain

Diabetes mellitus has been shown to impair respiratory function. The diaphragm is an important skeletal muscle involved in respiration. Hydrogen sulfide (H2S) is one of the three endogenous gas messengers in mammals, which exhibits anti-fibrotic activity in some types of diabetes-related complications. However, whether and how H2S exerts its anti-fibrotic activity on the diabetic diaphragmatic muscle remains unclear. In this study, we explored the anti-fibrotic activity of exogenous H2S on the diaphragm using a streptozotocin (STZ)-induced diabetic rat model. The results showed that diaphragmatic biomechanical parameters were decreased, whereas the levels of inflammatory cytokines, collagen, and nucleotide-binding oligomerization domain-like receptor protein (NLRP) 3 inflammasome-related protein expression were increased in diabetic diaphragms. This implies that diabetes causes fibrosis of the diaphragm muscle through activation of NLRP3 inflammasome. After supplementation with exogenous H2S, the diaphragmatic biomechanical and pathological alterations were ameliorated and activation of NLRP3 inflammasome was inhibited, followed by a decline in diaphragm muscle inflammation and fibrosis. These results demonstrate for the first time that exogenous H2S effectively attenuates STZ-induced diabetic diaphragm muscle fibrosis, and that the underlying mechanism may be associated with suppression of the NLRP3 inflammasome-mediated inflammatory reaction. Impact statement Diabetes mellitus is a group of chronic metabolic disorders, which causes serious damage to a variety of organs, such as the retina, heart, and skeletal muscle. The diaphragm is an important skeletal muscle involved in respiration in mammals. Fibrosis of the diaphragm muscle affects its contractility, which in turn impairs respiratory function. Accumulating evidence suggests that exogenous hydrogen sulfide (H2S) exhibits anti-fibrotic activity in diabetes mellitus, but whether and how H2S exerts this anti-fibrotic effect in the diabetic diaphragm remains unclear. The current work for the first time reveals that exogenous H2S attenuates hyperglycemia-induced fibrosis of the diaphragm muscle and strengthens diaphragmatic biomechanical properties in diabetes mellitus, and the mechanism may involve the alleviation of collagen deposition by suppression of the nucleotide-binding oligomerization domain-like receptor protein (NLRP) 3 inflammasome-mediated inflammatory reaction. Therefore, H2S supplementation could be used as an efficient targeted therapy against the NLRP3 inflammasome in the diabetic diaphragm.

The Initial Decrease in Effective Peritoneal Surface Area is Not Caused by an Increase in Hematocrit

1993 ◽  
Vol 13 (2_suppl) ◽  
pp. 53-56 ◽  
Author(s):  
Dirk G. Struijk ◽  
Raymond T. Krediet ◽  
Ger C.M. Koomen ◽  
Elisabeth W. Boeschoten ◽  
Franciscus J. Hoek ◽  
...  
Keyword(s):  
Surface Area ◽  
Fluid Transport ◽  
Transport Kinetics ◽  
Prospective Longitudinal Study ◽  
Fluid Removal ◽  
Peritoneal Surface ◽  
The Absolute ◽  
Relative Change ◽  
Prospective Longitudinal ◽  
First Time

The possible relationship between Initial changes In functional characteristics of the peritoneal membrane In time and hemoglobin (Hb) or hematocrit (Ht) was analyzed as part of a prospective longitudinal study. The patients were Investigated twice: the first time within 3 months after the start of continuous ambulatory peritoneal dialysis (CAPD), and again 4 months later. Mass transfer area coefficients (MTC) for low molecular weight solutes and net fluid removal were calculated during a 4-hour dwell, glucose 1.36%. Thirty-four patients were analyzed. MTC (mean±SD, mL/min/1.73 m2) were higher during the first examination: urea 22.6 versus 19.9, p<0.05; lactate 15.6 versus 13.8, p<0.001; creatinine 10.5 versus 9.3, p<0.05; glucose 9.4 versus 7.9, p<0.001. Net fluid removal was lower during the first examination: 28 versus 99 mL/mln/1.73 m2, p<0.05. Hb and Ht increased between the two examinations (Hb: 5.4 vs 6.1 mmol/L, p<0.001; Ht: 0.26 vs 0.29, p<0.001). No relation was found between the absolute or relative change In Hb or Ht and the absolute or relative change In solute and fluid transport between the same examinations. In conclusion, Hb and Ht Increased between the first and second examinations. The simultaneously observed changes in peritoneal transport kinetics could not be attributed to changes In Hb or Ht. Therefore, the changes In transport kinetics during the first months on CAPD are probably due to the recent start of the treatment, possibly by an Increase In peritoneal surface area. LocalIrritation by the dialysate may be the causative mechanism.

Mesoporous tantalum oxide photocatalysts for Schrauzer-type conversion of dinitrogen to ammonia

2005 ◽  
Vol 83 (4) ◽  
pp. 308-314 ◽  
Author(s):  
Chaoyang Yue ◽  
Michel L Trudeau ◽  
David Antonelli
Keyword(s):  
Surface Area ◽  
Tantalum Oxide ◽  
Catalytic Efficiency ◽  
Mesoporous Structure ◽  
Turnover Rates ◽  
Type Conversion ◽  
Electron Hole ◽  
Surface Areas ◽  
Before And After ◽  
First Time

Mesoporous tantalum oxide, Fe3+-doped mesoporous tantalum oxide, and bis(toluene) titanium reduced mesoporous tantalum oxide were used for the first time as Schrauzer-type photocatalysts for the conversion of dinitrogen to ammonia. The materials were characterized by XRD, TEM, XPS, and nitrogen absorption before and after catalytic runs. The results showed low to moderate activities depending on the composition. In contrast to previously studied Ti catalysts, Fe doping and heat pretreatment were not prerequisites for photocatalytic activity, but did improve the turnover rates by up to a factor of two. The optimal Fe loading for the tantalum oxides was found to be 1 wt% and the optimal heating condition at 300 °C for 3 h. Increased surface area and heat treatment were also found to improve activities. Contrary to our expectations, reduction of the mesostructure with bis(toluene) titanium had little effect on the catalytic activity. In spite of the dramatically higher surface areas of the mesoporous tantalum oxides as compared with bulk titanias used previously in this process, the overall catalytic activities were still less than those obtained in the Schrauzer system. This suggests that the increase in diffusion and surface area offered by the mesoporous structure is offset by the smaller crystalline domain sizes in the walls of the structure, leading to poor electron-hole separation and a reduction in catalytic efficiency. Key words: mesoporous, Schrauzer, ammonia, photocatalysis, tantalum oxide.

Adsorption of Aniline Using Novel Mesoporous Carbon Nitride

2014 ◽  
Vol 925 ◽  
pp. 135-139 ◽  
Author(s):  
Mei Shie Sam ◽  
Hendrik O. Lintang ◽  
Mohd Marsin Sanagi ◽  
Siew Ling Lee ◽  
Leny Yuliati
Keyword(s):  
Surface Area ◽  
Mesoporous Carbon ◽  
Carbon Nitride ◽  
Adsorption Process ◽  
Organic Pollutant ◽  
Comparison Study ◽  
Adsorption Sites ◽  
First Time ◽  
Mesoporous Carbon Nitride ◽  
Mcm 41

Aniline is a toxic organic pollutant that is abundantly present in the environment. One of approaches to remove the aniline is by adsorption process. In this study, mesoporous carbon nitride (MCN) was proposed for the first time to be a potential adsorbent for aniline. The adsorption studies were carried out at room temperature on the aniline solution with various initial concentrations for both bulk carbon nitride (BCN) and MCN. Owing to its larger surface area, the MCN showed much higher adsorption capacity towards aniline compared to the BCN. This result indicated that adsorbent with large surface area is very crucial in the adsorption of aniline. Comparison study was also carried out using mesoporous silica, MCM-41, which was reported to act as a good adsorbent for aniline. The adsorption capability of MCN was found to be higher than that of MCM-41. It was suggested that the MCN with larger pore diameter might have more suitable and favourable adsorption sites for aniline compared to MCM-41. This study obviously showed that MCN would be a new potential adsorbent for removal of aniline.

scholarly journals Melt Infiltration Processing of Foams Using Glass-Forming Alloys

2002 ◽  
Vol 754 ◽  
Author(s):  
C. San Marchi ◽  
A. Brothers ◽  
D. C. Dunand
Keyword(s):  
Thermal Conductivity ◽  
Metallic Glass ◽  
Relative Density ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Glass Forming ◽  
Melt Infiltration ◽  
First Time ◽  
Infiltration Techniques

ABSTRACTProcessing of foams from bulk metallic glass (BMG) alloys, using melt infiltration techniques, is reported for the first time. Foaming methods based on infiltration of two types of pattern materials are described: investment of a continuous refractory yielding very low relative density structures (5% dense relative to the BMG), and investment of a discontinuous refractory pellet bed yielding higher relative density (50–60% dense relative to the BMG). Both methods are capable of producing foam structures; however high surface area and diminished thermal conductivity, especially in lower density structures, make vitrification of the alloy difficult.

Observations with a different approach to morphological colour variation in an isopod population (Crustacea: Isopoda)

Biologia ◽  
2009 ◽  
Vol 64 (1) ◽  
Author(s):  
Belgin Camur-Elipek
Keyword(s):  
Surface Area ◽  
Brackish Water ◽  
Similarity Index ◽  
Bottom Surface ◽  
Colour Variation ◽  
Idotea Baltica ◽  
Water Lake ◽  
Colour Morphs ◽  
First Time ◽  
Brackish Water Lake

AbstractMorphological colour variation in Idotea baltica basteri Audouin, 1827 (Isopoda: Crustacea) is reported for the first time on populations from a brackish water lake (Kucukcekmece Lagoon) in Turkey. According to pigmentation characteristics, the isopods were described and sorted to ten different colour morphs which are named as maculata, maculata-lineata, uniformis, uniformis-lineata, immaculatum, immaculatum-lineata, nigrum, nigrum-lineata, albafusca, and albafusca-fasciatum. The similarity of the morphs was compared by defining digit codes to some of the visual pigmentation characteristics and calculating the Bray-Curtis similarity index of the colour morphs. The albafusca and albafusca-fasciatum forms were found to be the most similar to each other (similarity 96%), whereas immaculatum forms were considered the most different from maculata-lineata (similarity 50%). The morphs named maculata and maculata-lineata, having the highest abundance with 70%, belong to the most successful forms which may achieve crypsis by background matching in their living habitat in Kucukcekmece Lagoon which has sandy and rocky bottom surface area.

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