scholarly journals Management and relocation of nests of Podocnemis expansa (Schweigger, 1812) (Testudines, Podocnemididae) on the Crixás-Açu river, Brazil

2011 ◽  
Vol 71 (4) ◽  
pp. 975-982 ◽  
Author(s):  
AS. Gomes ◽  
PD. Ferreira Júnior
Keyword(s):  
At Risk ◽  
Rainy Season ◽  
Hatching Success ◽  
Incubation Temperature ◽  
Viable Alternative ◽  
Central Brazil ◽  
Podocnemis Expansa ◽  
The Mean ◽  
Palm Fronds ◽  
Artificial Shading

Podocnemis expansa nests in the sandbanks of the Crixás-Açu River in central Brazil during the dry season. With the return of the rainy season, the river banks are once again inundated, flooding nests and eggs and drowning hatchlings. This study evaluated relocation as an alternative to manage nests at risk of flooding. Forty P. expansa nests from four beaches of the Crixás-Açu were relocated to nurseries constructed in tanks filled with sand from the same river. Nine nests were covered with palm fronds to simulate shading conditions and to lower the incubation temperature. The base of the egg chamber was at a depth of 60 cm in all the nests. The duration of incubation varied for sunlit (49.1 ± 2.35 days) and shaded nests (51.7 ± 1.75 days), but did not change with nest position (center or edge of nurseries). Hatching success was 47.3 ± 13.6%, and did not vary significantly with sunlight/shade or nest position. The mean incubation temperature during the thermosensitivity period varied from 33 ± 1.56 °C to 34.1 ± 1.40 °C. The lowest mean temperature during the thermosensitivity period (31.9 ± 0.95 °C) and the highest proportion of males (up to 45% of hatchlings) were observed in a shaded nest. Most sunlit nests produced only females. The results suggest that relocation is a viable alternative in managing nests at risk of flooding during the rainy season in the Crixás-Açu. Moreover, artificial shading was shown to be an option to increase the proportion of males.

Incubation Temperature Influences the Duration of Egg Hatching and Early Development in the Boreal Digging Frog, Kaloula Borealis

2020 ◽  
Vol 3 (1) ◽  
pp. ACCEPTED
Author(s):  
Rho-Jeong Rae
Keyword(s):  
Water Temperature ◽  
Early Life ◽  
Rainy Season ◽  
Incubation Temperature ◽  
Life Stages ◽  
Early Life Stages ◽  
Egg Hatching ◽  
Significant Difference ◽  
The Mean ◽  
Hatching Rates

This study investigated the boreal digging frog, Kaloula borealis, to determine the egg hatching period and whether the hatching period is affected by incubation temperature. The results of this study showed that all the eggs hatched within 48 h after spawning, with 28.1% (±10.8, n=52) hatching within 24 h and 99.9% (±0.23, n=49) within 48 h after spawning. A significant difference was noted in the mean hatching proportion of tadpoles at different water temperatures. The mean hatching rates between 15 and 24 h after spawning was higher at a water temperature of 21.1 (±0.2) °C than at 24.1 (±0.2) °C. These results suggest that incubation temperature affected the early life stages of the boreal digging frog, since they spawn in ponds or puddles that form during the rainy season.

scholarly journals Temperature-sex determination in Podocnemis expansa (Testudines, Podocnemididae)

2011 ◽  
Vol 101 (3) ◽  
pp. 151-155 ◽  
Author(s):  
Kelly Bonach ◽  
Adriana Malvasio ◽  
Eliana R. Matushima ◽  
Luciano M. Verdade
Keyword(s):  
Sex Determination ◽  
Success Rate ◽  
Incubation Period ◽  
Clutch Size ◽  
Hatching Success ◽  
Incubation Temperature ◽  
Small Sample ◽  
Mato Grosso ◽  
Araguaia River ◽  
Podocnemis Expansa

This study has been carried out at the central region of the Araguaia river on the border between the states of Goiás and Mato Grosso in the Brazilian Amazon Basin from September to December 2000. We recorded temperature fluctuation, clutch-size, incubation period and hatching success rate and hatchlings' sex ratio of five nests of Podocnemis expansa (Schweigger, 1812). Despite the relatively small sample size we infer that: a) nests of P. expansa in the central Araguaia river have a lower incubation temperature than nests located further south; however, incubation period is shorter, hatching success rate is lower and clutch-size is larger; b) Podocnemis expansa may present a female-male-female (FMF) pattern of temperature sex-determination (TSD); c) thermosensitive period of sex determination apparently occur at the last third of the incubation period; and, d) future studies should prioritize the relationship between temperature variation (i.e., range and cycle) and embryos development, survivorship and sex determination.

scholarly journals Does the variance of incubation temperatures always constitute a significant selective force for origin of reptilian viviparity?

2012 ◽  
Vol 58 (6) ◽  
pp. 812-819 ◽  
Author(s):  
Hong Li ◽  
Zheng Wang ◽  
Ce Chen ◽  
Xiang Ji
Keyword(s):  
Hind Limb ◽  
Hatching Success ◽  
Incubation Temperature ◽  
Tail Length ◽  
Thermal Fluctuations ◽  
Limb Length ◽  
Selective Force ◽  
Sprint Speed ◽  
The Mean ◽  
Incubation Temperatures

Abstract To test the hypothesis that the variance of incubation temperature may have constituted a significant selective force for reptilian viviparity, we incubated eggs of the slender forest skink Scincella modesta in five thermally different natural nests and at two constant temperatures (18 °C and 21 °C). Our manipulation of incubation temperature had significant effects on incubation length and several hatchling traits (snout-vent length, tail length, fore-limb length, and sprint speed), but not on hatching success and other hatchling traits examined (body mass, head size, and hind-limb length). Incubation length was nonlinearly sensitive to temperature, but it was not correlated with the thermal variance when holding the thermal mean constant. The 18 °C treatment not only produced smaller sized hatchlings but also resulted in decreased sprint speed. Eggs in the nest with the greatest proportion of temperatures higher than 28 °C also produced smaller sized hatchlings. None of the hatchling traits examined was affected by the thermal variance. Thermal fluctuations did result in longer incubation times, but females would benefit little from maintaining stable body temperatures or selecting thermally stable nests in terms of the reduced incubation length. Our data show that the mean rather than the variance of temperatures has a key role in influencing incubation length and hatchling phenotypes, and thus do not support the hypothesis tested.

scholarly journals The viability of Sphaeridiotrema pseudoglobulus (Digenea) eggs following cold water storage as a possible overwintering strategy

Parasitology ◽  
1993 ◽  
Vol 107 (4) ◽  
pp. 441-447 ◽  
Author(s):  
C. W. McKindsey ◽  
J. D. McLaughlin
Keyword(s):  
Life Span ◽  
Storage Time ◽  
Hatching Success ◽  
Incubation Temperature ◽  
Cold Water ◽  
Water Storage ◽  
Potential Importance ◽  
Natural Conditions ◽  
Equivalent Length ◽  
The Mean

SUMMARYSphaeridiotrema pseudoglobulus is a digenean parasite believed to be involved in a yearly fall die-off of ducks in Québec, Canada. Hatching characteristics of eggs stored at 7°C for 0–28 weeks in the lab and following maintenance overwinter in a lake are described. The hatching success of eggs stored for 4–28 weeks remained constant (71–81 %) but slightly less than that observed in fresh eggs (90%). The hatching success of eggs kept overwinter under natural conditions did not differ from that of eggs stored an equivalent length of time in the lab at 7°C (74·7 and 75·8%, respectively). With the exception of fresh eggs (17·7 days), the mean hatch time of eggs steadily decreased with increased storage time (18·9 days following 4 weeks storage to 11·4 days at 28 weeks storage) due to a slow embryonation of the eggs at 7°C. Hatching characteristics of a subsample of eggs incubated at 10, 15 and 20°C were compared and the embryonation rate was found to increase with incubation temperature. The majority of eggs stored at 10°C embryonated but failed to hatch. When their incubation temperature was raised to 15°C, a further 46% hatched within the following week. The survivorship functions of miracidia hatching from eggs stored for 8, 12, 16 and 20 weeks differed but the mean expected life-span of the miracidia did not decline with increasing storage time as expected. The results of these experiments are discussed in relation to the potential importance of overwintered eggs in the development of the infective pool of metacercariae.

Discriminant Validation of the Test of Reading Performance (TORP) for Identifying Children at Risk of Reading Difficulties

2000 ◽  
Vol 16 (2) ◽  
pp. 139-146 ◽  
Author(s):  
Padeliadu Susana ◽  
Georgios D. Sideridis
Keyword(s):  
At Risk ◽  
Elementary School Students ◽  
Reading Difficulties ◽  
Reading Performance ◽  
Low Achievers ◽  
Children At Risk ◽  
School Students ◽  
Students At Risk ◽  
Group A ◽  
The Mean

Abstract This study investigated the discriminant validation of the Test of Reading Performance (TORP), a new scale designed to evaluate the reading performance of elementary-school students. The sample consisted of 181 elementary-school students drawn from public elementary schools in northern Greece using stratified random procedures. The TORP was hypothesized to measure six constructs, namely: “letter knowledge,” “phoneme blending,” “word identification,” “syntax,” “morphology,” and “passage comprehension.” Using standard deviations (SD) from the mean, three groups of students were formed as follows: A group of low achievers in reading (N = 9) including students who scored between -1 and -1.5 SD from the mean of the group. A group of students at risk of reading difficulties (N = 6) including students who scored between -1.5 and -2 SDs below the mean of the group. A group of students at risk of serious reading difficulties (N = 6) including students who scored -2 or more SDs below the mean of the group. The rest of the students (no risk, N = 122) comprised the fourth group. Using discriminant analyses it was evaluated how well the linear combination of the 15 variables that comprised the TORP could discriminate students of different reading ability. Results indicated that correct classification rates for low achievers, those at risk for reading problems, those at risk of serious reading problems, and the no-risk group were 89%, 100%, 83%, and 97%, respectively. Evidence for partial validation of the TORP was provided through the use of confirmatory factor analysis and indices of sensitivity and specificity. It is concluded that the TORP can be ut ilized for the identification of children at risk for low achievement in reading. Analysis of the misclassified cases indicated that increased variability might have been responsible for the existing misclassification. More research is needed to determine the discriminant validation of TORP with samples of children with specific reading disabilities.

COLONY OF THE FUNGUS Aspergillus oryzae AND SELF-AFFINE FRACTAL GEOMETRY OF GROWTH FRONTS

Fractals ◽  
1993 ◽  
Vol 01 (01) ◽  
pp. 11-19 ◽  
Author(s):  
SHU MATSUURA ◽  
SASUKE MIYAZIMA
Keyword(s):  
Aspergillus Oryzae ◽  
Environmental Conditions ◽  
Fractal Geometry ◽  
Nutrient Concentration ◽  
Incubation Temperature ◽  
Characteristic Exponent ◽  
Growth Front ◽  
Favorable Condition ◽  
The Self ◽  
The Mean

A variety of colony shapes of the fungus Aspergillus oryzae under varying environmental conditions such as the nutrient concentration, medium stiffness and incubation temperature are obtained, ranging from a homogeneous Eden-like to a ramified DLA-like pattern. The roughness σ(l, h) of the growth front of the band-shaped colony, where h is the mean front height within l of the horizontal range, satisfies the self-affine fractal relation under favorable environmental conditions. In the most favorable condition of our experiments, its characteristic exponent is found to be a little larger than that of the 2-dimensional Eden model.

scholarly journals Cycle length of nonsustanied ventricular tachycardias among ICD patients: implications on subsequent appropriate therapies

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Javier Jiménez-Candil ◽  
Olga Duran ◽  
Armando Oterino ◽  
Jendri Pérez ◽  
Juan Carlos Castro ◽  
...  
Keyword(s):  
At Risk ◽  
Secondary Prevention ◽  
Beta Blocker ◽  
Cycle Length ◽  
Close Relationship ◽  
Appropriate Therapy ◽  
The Mean ◽  
Ventricular Tachycardias ◽  
The Relationship

Abstract Background ICD patients with episodes of nonsustained ventricular tachycardias (NSVT) are at risk of appropriate therapies. However, the relationship between the cycle length (CL) of such NSVTs and the subsequent incidence of appropriate interventions is unknown. Methods 416 ICD patients with LVEF < 45% were studied. ICD programming was standardized. NSVT was defined as any VT of 5 or more beats at ≥ 150 bpm occurred in the first 6 months after implantation that terminated spontaneously and was not preceded by any appropriate therapy. The mean follow-up was 41 ± 27 months. Results We analyzed 2201 NSVTs (mean CL = 323 ms) that occurred in 250 patients; 111 of such episodes were fast (CL ≤ 300 ms). Secondary prevention (HR = 1.7; p < 0.001), number of NSVT episodes (HR = 1.05; 95% CI 1.04–1.07; p < 0.001) and beta-blocker treatment (HR = 0.7; p = 0.04) were independent predictors of appropriate interventions; however, the mean CL of NSVTs was not (p = 0.6). There was a correlation between the mean CL of NSVTs and the CL of the first monomorphic VT: r = 0.88; p < 0.001. This correlation was especially robust in individuals with > 5 NSVTs (r = 0.97; p < 0.001), with an agreement between both values greater than 95%. Patients with any fast NSVT experienced a higher incidence of VF episodes (26%) compared to those without NVSTs (3%) or with only slow NSVTs (7%); p < 0.001. Conclusions Unlike the burden, the CL of NSVTs is not a predictor of subsequent appropriate interventions. However, there is a close relationship between the CL of NSVTs and that of arrhythmias that will later lead to appropriate therapies.

scholarly journals Heterobeltiosis in French Marigold (Tagetes patula L.)

2016 ◽  
Vol 8 (8) ◽  
pp. 182
Author(s):  
Kanwar Priyanaka ◽  
Y. C. Gupta ◽  
S. R. Dhiman ◽  
R. K. Dogra ◽  
Sharma Madhu ◽  
...  
Keyword(s):  
Rainy Season ◽  
Quantitative Traits ◽  
Block Design ◽  
Tagetes Patula ◽  
Male Sterile ◽  
Randomized Block Design ◽  
Parental Material ◽  
The Mean ◽  
Parental Lines ◽  
Better Than

<p>The studies on heterosis were carried with four male sterile lines namely; ms<sub>7</sub>, ms<sub>8</sub>, ms<sub>9,</sub> ms<sub>10</sub> and 18 diverse pollinators as tester by using line × tester crossing programme. The 72 F<sub>1</sub> hybrids were produced and evaluated along with 22 parental lines during summer 2009 and rainy season 2009 in Randomized Block Design. Observations were recorded on nine quantitative traits during both the seasons. Highly significant variances for all the traits indicated the sufficient variability in the parental material for all the characters under study. The performance of F<sub>1</sub> hybrids was much better than the mean performance of parents during both the crop seasons. Appreciable heterosis was observed in all the characters, except flower weight in summer and plant height in rainy season.</p>

Stable Isotopes Analysis of Precipitation in Subtropical Plateau of Yunnan

2014 ◽  
Vol 1010-1012 ◽  
pp. 1059-1063
Author(s):  
Wei Guan ◽  
Tao Fan ◽  
Xiu Qin Zhu
Keyword(s):  
Stable Isotopes ◽  
Rainy Season ◽  
Mean Value ◽  
Dry Season ◽  
Precipitation Line ◽  
Stable Isotopic ◽  
Different Seasons ◽  
Geographical Position ◽  
The Mean ◽  
The Relationship

To elucidate the relationship between stable isotopes of precipitation (SIP) and the extreme drought in Kunming area, based on the stable isotopes data of the GNIP in Kunming site from 1986 to 2003, the precipitation line equation is brought forward and the seasonal change rule of stable isotopes are discussed. The stable isotopic compositions of precipitation exhibit great diversities in different seasons during to influences of multiple factors, such as monsoon, rainfall amount moisture source and others. The δ18O values in rainwater exhibit significant seasonal variations, the average of-10.12‰ in rainy season, the dry season is-4.5‰, having lower values in the rainy season and higher one in the dry season. The amount effect of precipitation is very distinct, that concealed the temperature effect. Got the special geographical position,dvalues present unique characteristics, the average ofdvalues is 10.78‰ in rainy season, and is 4.86‰ in dry season, the mean value is generally lower than most parts of the world.

scholarly journals Association between Nutritional Status Determined By Mini Nutritional Assessment and Serum Marker Levels in Older Adults at Eldercare Facilities

2015 ◽  
Vol 1 (1) ◽  
Author(s):  
Angel G Hilerio Lopez
Keyword(s):  
Older Adults ◽  
At Risk ◽  
Nutritional Status ◽  
Nutritional Assessment ◽  
Mini Nutritional Assessment ◽  
Serum Marker ◽  
Cross Sectional ◽  
Mean Values ◽  
Significant Difference ◽  
The Mean

Malnutrition in the older adult is an ongoing situation in Mexico and is most apparent in individuals that reside in hospitals, nursing homes, and retirement homes. For that reason, it is necessary to evaluate the nutritional status of these adults by means of the Mini Nutritional Assessment (MNA) and levels of three serum indicators that are commonly ordered when making malnutrition diagnosis. An analytical cross-sectional study was carried out on 100 older adults residing in eldercare facilities. Nutritional status was evaluated by means of the MNA and three serum indicators (albumin, ferritin, and hemoglobin). Descriptive statistics were used to analyze sociodemographic characteristics, and a Student’s t test, based on gender and reference values, was used to compare mean values of the three serum indicators.  A Chi-square test was used to compare proportions in individuals, based on gender, who had normal nutritional status or were malnourished, and who were at-risk of malnutrition.  A One-way ANOVA with Scheffé post hoc test was used to identify the association between serum indicators and nutritional status of older adults. Of the 100 older adults studied, 53% were men and 47% were women. The mean age was 85±0.7 years. According to the MNA, 20% had normal nutritional status, 55% were at-risk of malnutrition, and 25% were malnourished. The mean indicator values were: albumin 4.7±0.04 g/dL, ferritin 74.2±8.7 ng/mL, and hemoglobin 13.0±0.1 g/dL. No significant association was found between serum indicators and each MNA classification; however, when the same indicators were compared between the sexes, hemoglobin showed a significant difference (P=0.037). Women had lower values but those values did not extend beyond the established physiological range for this population. There was a 55% prevalence of risk of malnutrition in the nutritional status of older adults living in Mexican eldercare facilities in a Mexican province and it was even more frequent in women. 

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