scholarly journals Studi Morfologi, Ontogeni, Dan Strategi Reproduksi Pada Melanoides Tuberculata (Müller , 1774) Dan Stenomelania Punctata (Lamarck, 1822) (Gastropoda: Cerithioidea: Thiaridae)

2021 ◽  
Vol 20 (2) ◽  
pp. 171-180
Author(s):  
Nur Rohmatin Isnaningsih
Keyword(s):  
Reproductive Strategy ◽  
Size Range ◽  
Wide Distribution ◽  
Brood Pouch ◽  
Free Swimming ◽  
Shell Form ◽  
Melanoides Tuberculata ◽  
Reproduction System ◽  
Embryonic Shell ◽  
The Difference

The freshwater Melanoides tuberculata (Thiarid) has wide distribution and have many variation in color, size, and scluptured of their shells. Comparing with another Thiarid so called Stenomelania punctata, shell of M. tuberculata similar in having turreted shape, blackish color, number of whorls, and size of the shells. This study aim to compare more detailed between M. tuberculata and S. punctata based on their morphology, ontogeny and type of reproduction. Ontogeny studies of these two species show that M. tuberculata produces juveniles in embryonic shell form during their reproduction. This embryonic shell is nourished and developed in the subhaemocoelic brood-pouch organ as evidenced by being found in the size range 0.12–5.95 mm. One individu M. tuberculata can produce 1–66 embryonic shells. Meanwhile, in subhaemocoelic brood-pouch of S. punctata only the unshell embryo was seen and embryonic shell was not found. The difference of reproduction system determines the reproductive strategy in both species. M. tuberculata conduct euviviparity reproduction whereas S. punctata is ovoviviparous that releases juveniles in free-swimming veliger form.

scholarly journals Geometry and the Mechanism of Landslide Occurrence in a Limestone Area – Case Examples of Landslides in Vietnam and from Europe, China, and Japan –

2021 ◽  
Vol 16 (4) ◽  
pp. 646-657
Author(s):  
Bui Duc Tung ◽  
Ngoc Ha Do ◽  
Nguyen Kim Thanh ◽  
Le Hong Luong ◽  
Osamu Watanabe ◽  
...  
Keyword(s):  
Southern China ◽  
Accretionary Prism ◽  
Wide Distribution ◽  
Case Examples ◽  
Landslide Occurrence ◽  
Sedimentary Characteristics ◽  
Tethys Sea ◽  
Wide Range ◽  
The Difference ◽  
Mechanism Of Landslide

Landslide damage has been reported in many limestone areas in Europe, where the population lives close to limestone areas, and in Guilin in southern China and Ha Long in Vietnam, which are known for their unique limestone landscapes. There are few studies on the mechanism and type of landslide motion in and around such limestone areas. The lack of basic data is a problem for risk assessment and countermeasures in limestone areas. In this study, we summarized the causes and mechanisms of landslide occurrence, including geology and groundwater, focusing on six landslides that occurred in limestone areas in northern Vietnam, and classified them into six types of landslide movement. In the case of Japan, the occurrence of landslides in limestone areas is rare despite the wide distribution of limestone, and it is difficult to classify the type of movement. Differences in the landslide mechanisms are caused by the difference between limestones generated in the pelagic environment of Japan and limestones developed along the Tethys Sea coast, which are mixed with pelitic rocks as shallow-water sediments in Europe, China, and Vietnam. It is necessary to elucidate the relationship between landslides and the formation environment and sedimentary characteristics of limestone as an accretionary prism based on comparisons of a wide range of cases in future studies.

Shell and Seed Size Relationships in Peanuts1

1981 ◽  
Vol 8 (1) ◽  
pp. 21-24 ◽  
Author(s):  
Ignacio J. de Godoy ◽  
A. J. Norden
Keyword(s):  
Seed Size ◽  
Plant Density ◽  
Wide Distribution ◽  
Seed Length ◽  
Arachis Hypogaea L ◽  
Length Width ◽  
Pericarp Color ◽  
The Difference ◽  
F2 Generation ◽  
F1 Generation

Abstract Three crosses and their reciprocals between peanut (Arachis hypogaea L.) genotypes differing in pod and seed sizes were made to investigate relationships between the pericarp (shell) and seed. Length, width, and weight of the fruit and seed from the F1 generation and selfed parentals were compared. The F2 generation along with plants from the parental lines were grown in the field. The weight, width, and volume of dried fruits and seeds, as well as shell thickness, were obtained from samples of 30 visually mature pods from each plant. Density of fruits and seeds, internal pericarp color, and shelling percentage were also recorded. Length, width, and weight of the F1 seeds tended to be similar to the selfed seeds from the same plants, showing possible maternal influence. The wide distribution in fruit volume obtained among F2 plants is indicative of quantitative inheritance. The larger the difference in fruit and seed size between the parents, the more pronounced was the skewness of the size distributions of the progeny toward the smaller parent. Estimates of pheno-typic correlations for fruit and seed volume were high and positive in most cases. However, fruit density vs fruit volume correlations were essentially negative suggesting that seeds grown inside pods with genetically smaller cavities may be compacted by the shell.

scholarly journals Effects of multi-charge on aerosol hygroscopicity measurement by a HTDMA

2021 ◽  
Vol 14 (2) ◽  
pp. 1293-1301
Author(s):  
Chuanyang Shen ◽  
Gang Zhao ◽  
Chunsheng Zhao
Keyword(s):  
Size Range ◽  
Field Measurements ◽  
Submicron Particles ◽  
Compression Effect ◽  
Hygroscopic Properties ◽  
Multiply Charged ◽  
Number Ratio ◽  
Charged Aerosols ◽  
The Difference ◽  
Aerosol Hygroscopicity

Abstract. The humidified tandem differential mobility analyzer (HTDMA) is widely used to measure the hygroscopic properties of submicron particles. The size-resolved aerosol hygroscopicity κ measured by a HTDMA will be influenced by the contribution of multiply charged aerosols, but this effect on field measurements has seldom been discussed for previous field measurements. Our calculations demonstrate that the number ratio of multiply charged particles is quite considerable for some specific sizes between 100 and 300 nm, especially during a pollution episode. The presence of multiple charges will lead to a compression effect on the aerosol hygroscopicity in HTDMA measurements. Therefore, we propose a new algorithm that performs multi-charge correction of the size-resolved hygroscopicity κ, taking both the compression effect and the multi-charge number contribution into consideration. Application of the algorithm to field measurements showed that the relatively high hygroscopicity in the accumulation size range leads to the overestimation of the hygroscopicity of particles smaller than 200 nm. The low hygroscopicity of coarse-mode particles leads to the underestimation of the hygroscopicity of accumulation particles between 200 and 500 nm in size. The difference between the corrected and measured κ values can be as large as 0.05, highlighting that special attention must be paid to the multi-charge effect when a HTDMA is used for aerosol hygroscopicity measurements.

scholarly journals Altitudinal variation of the sex ratio and segregation by gender in the dioecious plant Mercurialis perennis L. (Euphorbiaceae) in Serbia

2007 ◽  
Vol 59 (3) ◽  
pp. 193-198 ◽  
Author(s):  
Dragana Cvetkovic ◽  
V. Jovanovic
Keyword(s):  
Sex Ratio ◽  
Wide Distribution ◽  
Spatial Segregation ◽  
Sexually Dimorphic ◽  
Altitudinal Variation ◽  
Altitudinal Range ◽  
Spatio Temporal ◽  
The Difference ◽  
Spatial Segregation Of Sexes ◽  
Male Frequency

The sex ratio is one of the most intriguing problems for evolutionary biologists. Spatio-temporal variation of male frequency in sexually dimorphic plant species, spatial segregation, and differential investment of the two sex functions have attracted much research interest. In this study, we examined altitudinal variation of the sex ratio and segregation by gender in Mercurialis perennis (dog?s mercury), a dioecious anemophilous species with wide distribution. The eight studied populations from Serbia represented an altitudinal range of 196 to 1480 m. Sex ratio was significantly biased in seven of the eight populations, with males outnumbering females 3.91:1 in the lowest-altitude population. Our results support the notion of spatial segregation of sexes along on altitudinal gradient: the frequency of males decreased with altitude, from 79.6% to 41.0%. The sex ratio was not significantly correlated with population density. We also examined intersexual differences of plant height in two populations from the extremes of the studied altitudinal range. Males were the larger sex in both populations, though the difference was not significant in the high-altitude population. .

scholarly journals Perbedaan Hasil Belajar Siswa MAN I Takengon Menggunakan Pembelajaran Kooperatif Tipe Student Teams Achievment Division (STAD) Dan Tipe Jigsaw Pada Materi Sistem Reproduksi Manusia

2017 ◽  
Vol 2 (2) ◽  
pp. 99
Author(s):  
Finta Yani Afrizal ◽  
Mudatsir Mudatsir ◽  
M. Ali Sarong
Keyword(s):  
Test Data ◽  
Human Reproduction ◽  
Control Group ◽  
Control Group Design ◽  
Cooperative Model ◽  
Concept Understanding ◽  
Reproduction System ◽  
Student Teams ◽  
Post Test ◽  
The Difference

Penelitian ini bertujuan untuk mengetahui perbedaan hasil belajar siswa menggunakan model pembelajaran kooperatif tipe STAD dan Jigsaw pada materi sistem reproduksi manusia. Metode penelitian adalah metode eksperimen dengan desain kontrol grup tes awal dan tes akhir. Penelitian telah dilaksanakan pada kelas XI IPA 3 menggunakan model kooperatif tipe STAD dan kelas XI IPA 1 menggunakan model kooperatif tipe Jigsaw di MAN I Takengon. Instrumen yang digunakan adalah instrumen tes hasil belajar. Teknik pengumpulan data dengan mengumpulkan data kemampuan awal siswa (pre-test), data kemampuan akhir siswa (post-tes), data peningkatan pemahaman konsep (N-Gain). Analisis data hasil belajar menggunakan uji-t. Hasil penelitian menunjukkan bahwa hasil belajar siswa kelas eksperimen STAD dan Jigsaw diperoleh t hitung 25,20 dan t tabel 1,65. Kesimpulan dari penelitian ini adalah terdapat perbedaan hasil belajar siswa antara kelas eksperimen STAD dan Jigsaw. Kata Kunci: Kooperatif tipe STAD, Jigsaw, Sistem Reproduksi Manusia. This research is aimed to know the difference of study result using cooperative study model for STAD and Jigsaw type in the material of human reproduction system material. The research method is experiment method with one control group design for beginning and ending test. It has been done at XI IPA 3 class using cooperative model of STAD type and XI IPA 1 class using cooperative model of Jigsaw type at MAN 1 Takengon. Instruments used are study result test. Data collecting techniques by collecting data of students beginning capability (pre test), data of students ending capability (post test), data of concept understanding improvement (N-Gain). Data analysis of study result was using t-test. The result showed that students’ study result of STAD and Jigsaw experiment class gives t-counted is 25,20 and t-table is 1,65. The conclusion of this research was, there was a student study result difference between STAD experiment class and Jigsaw. Keyword: CooperativeSTAD, Jigsaw, Reproductive System.

scholarly journals Carriage of a new epidemic strain of Neisseria meningitidis and its relationship with the incidence of meningococcal disease in Galicia, Spain

1999 ◽  
Vol 123 (3) ◽  
pp. 349-357 ◽  
Author(s):  
S. FERNÁNDEZ ◽  
L. ARREAZA ◽  
I. SANTIAGO ◽  
A. MALVAR ◽  
S. BERRÓN ◽  
...  
Keyword(s):  
Meningococcal Disease ◽  
Disease Incidence ◽  
Vaccination Campaign ◽  
Wide Distribution ◽  
Reference Laboratory ◽  
Epidemic Strain ◽  
Carriage Rate ◽  
High Incidence ◽  
The Difference ◽  
Low Incidence

In Galicia, Spain, a dramatic increase in the incidence of meningococcal disease was seen in the 1995–6. The annual incidence rose to 11 per 105 inhabitants, and 80% of identified strains were C[ratio ]2b[ratio ]P1.2,5. This led to the implementation of an intensive A+C vaccination campaign for the population aged 18 months to 19 years. During this campaign the prevalence of carriage in areas with high and low incidence was studied. Nasopharyngeal swabs were taken from 9796 subjects immediately before the administration of meningococcal vaccine, plated onto Thayer–Martin plates, incubated and sent for analysis to the Reference Laboratory for Neisseria in Spain. The prevalence of the C[ratio ]2b[ratio ]P1.2,5 strains was 0·6% (95% CI 0·29–0·88) in the high incidence area, and 0·41% (95% CI 0·00–1·04) in the low incidence area, and that of serogroup C (all strains) 1·36% (95% CI 0·80–1·80) and 0·89% (95% CI 0·09–1·69) respectively. The prevalence of N. meningitidis (all strains) was almost the same in both areas (8%). Carriers of the epidemic strain were not found in the 2–4 year age group, that most affected by the disease.Our data showed a wide distribution but a low carriage rate of the epidemic strain C[ratio ]2b[ratio ]P1.2,5 in the high and low disease incidence areas studied; the difference in the carriage rates between the two areas was not statistically significant.

Reliability and Sensitivity of Reaction Time Measurements During Quasi-Realistic Soccer Situations

Motor Control ◽  
2021 ◽  
pp. 1-11
Author(s):  
Lazar Tomic ◽  
Danica Janicijevic ◽  
Aleksandar Nedeljkovic ◽  
Bojan Leontijevic ◽  
Amador García-Ramos
Keyword(s):  
Reaction Time ◽  
Coefficient Of Variation ◽  
Size Range ◽  
High Reliability ◽  
Intraclass Correlation ◽  
Stimulus Presentation ◽  
Soccer Players ◽  
Force Development ◽  
Professional Soccer ◽  
The Difference

Reliability and sensitivity of reaction time (RT) during quasi-realistic soccer situations was explored in 10 professional soccer players (skilled; age = 20.9 ± 3.6 years) and 10 males without soccer experience (nonskilled; age = 23.4 ± 0.5 years). The participants were instructed to react as fast as possible to a stimulus presented via the video-based method while standing on force platforms. RT was computed as the difference between the instant when the rate of force development of any leg reaches 5% of its maximal value and the instant of stimulus presentation. The results revealed acceptable to high reliability of RT (intraclass correlation coefficient median = .90; coefficient of variation ≤ 5.83%), and shorter RT for skilled compared with nonskilled participants in three out of eight comparisons (effect size range = 1.00–1.41). The video-based methods can be confidently used to assess the RT in soccer players.

scholarly journals Extracellular and cellular proteins of rat cells with O-glycosidically linked fucose

1985 ◽  
Vol 225 (1) ◽  
pp. 59-65 ◽  
Author(s):  
P A Morton ◽  
S M Steiner
Keyword(s):  
Population Density ◽  
Growth Medium ◽  
Cell Population ◽  
Size Range ◽  
Molecular Size ◽  
Wide Distribution ◽  
Substantial Proportion ◽  
Particulate Fraction ◽  
Cellular Proteins ◽  
Associated Proteins

Fucose-labelled proteins were examined for the release of low-Mr O-linked fucose substituents after mild alkaline-borohydride treatment. A component tentatively identified as glucosylfucitol (DS) and an apparently higher-Mr component (TS), which also contained fucitol, were observed to be released over a broad molecular-size range of proteins. Approx. 90% of the DS-releasing proteins were in the particulate fraction, whereas only approx. 66% of the TS-releasing proteins were in that fraction. In addition to cell-associated proteins, a substantial proportion of DS-containing proteins were shed into the medium. For example, after 96 h of labelling there was 6-fold more of these components in the growth medium than were cell-associated. Moreover, the incorporation of labelled fucose into both the DS and TS appeared to be cell-population-density-dependent. Despite the apparent wide distribution of these novel fucose substituents in cellular proteins, it seems reasonable to suggest that they have not been routinely observed largely because each represents less than 0.5% of the fucose bound to protein.

Effect of Dispersoids on Softening Behavior in Cu-Fe-P Alloys for Lead Frames

2007 ◽  
Vol 539-543 ◽  
pp. 2258-2263
Author(s):  
Yasuhiro Aruga ◽  
Naohiro Hara ◽  
Katsura Kajihara
Keyword(s):  
Grain Size ◽  
Fine Particles ◽  
Residue Analysis ◽  
Average Diameter ◽  
Wide Distribution ◽  
Quantitative Aspect ◽  
Softening Behavior ◽  
Grain Size Distributions ◽  
The Difference ◽  
Recrystallized Grain Size

The effect of the amount of dispersoids on softening behavior and recrystallized microstructure of Cu-Fe-P alloy was examined by the extracted residue analysis method. The degrees of contribution of larger particles (larger than 1μm in an average diameter) and smaller ones (less than 0.1μm) to the softening behavior were considered in the quantitative aspect, respectively. It was found that the change of the order of 10-1mass% in the amounts of both particles has a great effect on softening behavior. The difference in the amount of fine particles changes recrystallized grain size distributions at similar hardness. In the specimen with a small amount of fine particles, coarse grains and wide distribution of grain size were observed after annealing. As a result, it was revealed that fine and homogeneous recrystallized microstructure was obtained due to just 0.35mass% of fine partcles, even if the amount of large particles increased.

scholarly journals Examination of the Watershed-Wide Distribution of Escherichia coli along Southern Lake Michigan: an Integrated Approach

2006 ◽  
Vol 72 (11) ◽  
pp. 7301-7310 ◽  
Author(s):  
Richard L. Whitman ◽  
Meredith B. Nevers ◽  
Muruleedhara N. Byappanahalli
Keyword(s):  
Escherichia Coli ◽  
Lake Michigan ◽  
Integrated Approach ◽  
Wide Distribution ◽  
Beach Sand ◽  
Natural Habitats ◽  
Coastal Watershed ◽  
E Coli ◽  
The Difference ◽  
Beach Water

ABSTRACT Recent research has highlighted the occurrence of Escherichia coli in natural habitats not directly influenced by sewage inputs. Most studies on E. coli in recreational water typically focus on discernible sources (e.g., effluent discharge and runoff) and fall short of integrating riparian, nearshore, onshore, and outfall sources. An integrated “beachshed” approach that links E. coli inputs and interactions would be helpful to understand the difference between background loading and sewage pollution; to develop more accurate predictive models; and to understand the differences between potential, net, and apparent culturable E. coli. The objective of this study was to examine the interrelatedness of E. coli occurrence from various coastal watershed components along southern Lake Michigan. The study shows that once established in forest soil, E. coli can persist throughout the year, potentially acting as a continuous non-point source of E. coli to nearby streams. Year-round background stream loading of E. coli can influence beach water quality. E. coli is present in highly variable counts in beach sand to depths just below the water table and to distances at least 5 m inland from the shore, providing a large potential area of input to beach water. In summary, E. coli in the fluvial-lacustrine system may be stored in forest soils, sediments surrounding springs, bank seeps, stream margins and pools, foreshore sand, and surface groundwater. While rainfall events may increase E. coli counts in the foreshore sand and lake water, concentrations quickly decline to prerain concentrations. Onshore winds cause an increase in E. coli in shallow nearshore water, likely resulting from resuspension of E. coli-laden beach sand. When examining indicator bacteria source, flux, and context, the entire “beachshed” as a dynamic interacting system should be considered.

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