TEM studies of tweed microstructures in annealed amelia albite

1990 ◽  
Vol 48 (4) ◽  
pp. 1064-1065
Author(s):  
Y. J. Kim ◽  
D. M. Henderson
Keyword(s):  
Annealing Time ◽  
The Other ◽  
Frequency Of Occurrence ◽  
Systematic Trend ◽  
Tweed Structure

Natural Amelia albite (Ab99.3An0.1Or0.6) annealed at 1073° and 924°C for various periods up to 140 days has been studied by NMR. TEM studies of the same sample revealed a distinct tweed microstructure in some samples annealed at both 1073°C and 924°C. On the whole, the quasi-regular tweed has a periodicity of 100 - 200 Å in both directions, one nearly normal to b* and the other approximately parallel to b*, which gives rise to two-directional streaking in SADP’s (Fig. 1 and 2). However, there are some differences in the tweed structure developed on annealing at 1073°C and at 924°C in albite.Albite samples annealed at 1073° show a systematic trend in their development of tweed structures: the regularity, periodicity, and frequency of occurrence increase with annealing time during the first 3 days, and then decrease gradually until no tweed microstructures are seen in samples annealed for more than 15 days. The tweed structure proceeds locally to form one-directional twin-like microstructures.

scholarly journals The role of the observed tropical convection in the generation of frost events in the southern cone of South America

2008 ◽  
Vol 26 (6) ◽  
pp. 1379-1390 ◽  
Author(s):  
G. V. Müller ◽  
T. Ambrizzi ◽  
S. E. Ferraz
Keyword(s):  
South America ◽  
Large Scale ◽  
Rossby Waves ◽  
Tropical Convection ◽  
The Other ◽  
Linear Wave ◽  
Frequency Of Occurrence ◽  
The South ◽  
Cold Events ◽  
Extreme Cold

Abstract. Based on previous results obtained from observations and linear wave theory analysis, the hypothesis that large-scale patterns can generate extreme cold events in southeast South America through the propagation of remotely excited Rossby waves was already suggested. This work will confirm these findings and extend their analysis through a series of numerical experiments using a primitive equation model where waves are excited by a thermal forcing situated in positions chosen according to observed convection anomalies over the equatorial region. The basic state used for these experiments is a composite of austral winters with maximum and minimum frequency of occurrence of generalized frosts that can affect a large area known as the Wet Pampas located in the central and eastern part of Argentina. The results suggest that stationary Rossby waves may be one important mechanism linking anomalous tropical convection with the extreme cold events in the Wet Pampas. The combination of tropical convection and a specific basic state can generate the right environment to guide the Rossby waves trigged by the tropical forcing towards South America. Depending on the phase of the waves entering the South American continent, they can favour the advection of anomalous wind at low levels from the south carrying cold and dry air over the whole southern extreme of the continent, producing a generalized frost in the Wet Pampa region. On the other hand, when a basic state based on the composites of minimum frosts is used, an anomalous anticyclone over the southern part of the continent generates a circulation with a south-southeast wind which brings maritime air and therefore humidity over the Wet Pampas region, creating negative temperature anomalies only over the northeastern part of the region. Under these conditions even if frosts occur they would not be generalized, as observed for the other basic state with maximum frequency of occurrence of generalized frosts.

Nest density and other observations on a population of Aneuretus simoni Emery, 1893 (Formicidae, Aneuretinae) and other ants in Indikada Mukalana Forest Reserve in Sri Lanka

2016 ◽  
Vol 4 (12) ◽  
pp. 1 ◽  
Author(s):  
Ratnayake K. S. Dias ◽  
Warnakulasuriyage S. Udayakantha
Keyword(s):  
Sri Lanka ◽  
Current Distribution ◽  
The Other ◽  
Nest Density ◽  
Sri Lankan ◽  
Frequency Of Occurrence ◽  
Pitfall Traps ◽  
Forest Reserve ◽  
Species Frequency ◽  
Nest Abundance

The Sri Lankan Relict Ant, Aneuretus simoni Emery, survives in several wet zone and intermediate zone forests in Sri Lanka. Nests of this species and other ants were surveyed at 159 m and 291 m elevations in Indikada Mukalana Forest Reserve by laying 20 quadrats of 1 m × 1 m at two plots of each locality in December, 2015. The number of ant nests within each quadrat was recorded; then the frequency of nest occurrence out of 40 quadrats, percentage nest abundance and mean nest density of A. simoni, as well as associated ant fauna were calculated. Percentage frequency of worker ant occurrence was also investigated using pitfall traps. Eighteen genera and 21 species in Aneuretinae, Dolichoderinae, Formicinae, Myrmicinae and Ponerinae were recorded from the two methods. Nests of A. simoni were found only in the locality at 291 m altitude in the forest; 17.5 % of quadrats with an A. simoni colonies, 9.7% of nest abundance in relation to that of other ant species and 0.18 m2 ofmean nest density were observed. Nest density of A. simoni had the fourth rank among that of the other species. Frequency of occurrence of A. simoni workers in the pitfall traps at lower and upper elevations was 2% and 3%, respectively. An actualized map showing the current distribution of A. simoni is produced.

Effect of Intercritical Annealing Time on Microstructure and Mechanical Behavior of Advanced Medium Mn Steels

2012 ◽  
Vol 706-709 ◽  
pp. 2693-2698 ◽  
Author(s):  
A. Arlazarov ◽  
M. Gouné ◽  
O. Bouaziz ◽  
A. Hazotte ◽  
F. Kegel
Keyword(s):  
Mechanical Behavior ◽  
Annealing Time ◽  
Room Temperature ◽  
Intercritical Annealing ◽  
Tensile Tests ◽  
The Other ◽  
Metastable Austenite ◽  
High Fraction ◽  
Cold Rolled ◽  
Strength And Ductility

The study about the influence of intercritical annealing time on a cold rolled 0.1%C – 4.6%Mn (wt.%) steel was performed. The tensile tests show an interesting balance between strength and ductility especially after 7 hours annealing at 670°C. A part of this good result can be explained by the presence of rather high fraction of metastable austenite at room temperature. On the other hand a very complex microstructure combining lath-like and polygonal features was observed making the interpretation complicated.

scholarly journals USING BOARS OF CANADIAN BREEDING TO IMPROVE THE MEAT QUALITIES OF LARGE WHITE PIGS

2018 ◽  
pp. 83-92
Author(s):  
V. A. Bekenеv ◽  
V. I. Frolova ◽  
V. S. Deeva ◽  
I. V. Bolshakova ◽  
Yu. V. Frolova
Keyword(s):  
Growth Rate ◽  
Live Weight ◽  
The Other ◽  
Fourth Generation ◽  
Control Group ◽  
Thoracic Vertebrae ◽  
Frequency Of Occurrence ◽  
Large White ◽  
Significant Difference ◽  
Meat Productivity

Three experiments were carried out to improve the meat productivity of pigs of Large White (LW) breed of russian selection by different variants of crossing with the Yorkshire (Y) breed of canadian selection. There were no significant differences between the groups in terms of reproductive qualities. Two-breed pigs (LW x Y) grew more intensively and the live weight of the piglet at the 30 days was 8,7 kg, which is higher than in the other groups with a significant difference (P <0,05). When the live weight of 100 kg was reached, the вackfat thickness of the fat over 6-7 thoracic vertebrae was 26,3 mm compared to 30,7 mm in purebred pigs of the LW of the breed (P <0,001), the area of the muscular eye was respectively 45,1 cm 2 and 30,6 cm 2 (P <0,001). In the fourth generation of reproductive and absorbent crossing of pigs of LW and Y of breeds, the thickness of the fat on the carcasses of pigs was 21,2 mm (Р < 0.001), which is 30-39 % less than for the LW carcasses, the area of the muscular eye was 44 mm. In three-breed hybrids (LW x D) x L, the age of reaching 100kg was less by 12,5 days (P <0,01), the thickness of the fat was 23,6 mm, that is, it was 11,4 mm less (P < 0,001) in comparison with the control group. The replacement pigs obtained from the absorbent crossing (LW x Y) x Y showed the best results for the вackfat thickness - 19,2 mm, but they were inferior to the purebred Y (13,0 mm) (P <0,001). In the sows of this combination, 11,6 piglets were born alive, the number of piglets at weaning was 10,6, the weight of the nest in the 30-day was 78,7 kg. Differences in the frequency of occurrence of certain antigenic factors of blood in animals of different combinations of breeds are revealed. In animals that have the EAE allele edf, a higher growth rate is revealed, but thicker the backfat.

P–049 The presence of double heads is associated with increased frequency of the other sperm abnormalities

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
M Handzhiyska ◽  
D Parvanov ◽  
R Ganeva ◽  
D Aleksandrova ◽  
E Tascudi ◽  
...  
Keyword(s):  
Normal Forms ◽  
Negative Impact ◽  
The Other ◽  
Frequency Of Occurrence ◽  
Vitro Fertilization ◽  
Multiple Defects ◽  
Sperm Abnormalities ◽  
Registration Number ◽  
Morphological Defects

Abstract Study question Is there an association between the presence of spermatozoa with double heads and the other sperm abnormalities in human semen? Summary answer Patients with double-headed spermatozoa had a significantly increased percentage of morphological abnormalities (head, midpiece and tail defects). What is known already The morphological evaluation of spermatozoa has a prognostic value for successful IVF procedure. It has been proven that certain morphological defects have a negative impact on fertilization, embryo quality, and pregnancy outcome in in-vitro fertilization cycles. Sperm abnormalities, such as double head, double tail and thin midpiece are rarely observed. However, their effect on the other sperm defects has not been well studied yet. The aim of this study was to examine the effect of the presence of double-headed spermatozoa on the frequency of occurrence of the other sperm defects. Study design, size, duration This retrospective study includes 2140 men aged between 18 and 73 years, with a mean of 36 years. It was conducted at Nadezhda Women’s Health Hospital, Bulgaria between October 2015 and August 2020. A comparative analysis was performed between semen samples with and without double-headed spermatozoa and the other sperm abnormalities, as well as the percentage of morphologically normal forms. Participants/materials, setting, methods Morphological analysis was performed according to the Kruger’s strict criteria. Totally 23 types of abnormalities were determined: head defects (small, large, amorphous, elongated, round, pear-shaped, double, acephalic, detached head, small and large acrosomal areas and spermatozoa without acrosome), midpiece defects (thick, bent, asymmetric, thin midpiece and cytoplasmic droplets), tail defects (stumped, coiled and double tail), acrosomal vacuoles, nuclear vacuoles and multiple defects. Statistics: Mann-Whitney U-test and T-test; P ≤ 0.05. Main results and the role of chance Presence of double-headed spermatozoa was observed in 12.62% (270/2140) of the studied samples. In these patients the frequency of occurrence of double-headed spermatozoa ranged between 1% and 29% with a mean of 0.41%±1.71%. Men with double-headed spermatozoa had significantly higher percentage of spermatozoa with small heads (24.51%±22.65%, P = 0.04), round heads (11.69%±10.13%, P &lt; 0.01), nuclear vacuoles (10.64%±5.25%, P &lt; 0.01), sperm without acrosome (9.76%±8.61%, P = 0.05), asymmetric midpiece (4.73%±3.96%, P &lt; 0.05), bent midpiece (8.9%±7.22%, P &lt; 0.01), thin midpiece (2.13%±4.44%, P &lt; 0.01), double tail (1.78%±0.8%, P &lt; 0.01), detached head (1.98%±1.42%, P &lt; 0.01), stumped tail (6.03%±5.19%, P = 0.02), and cytoplasmic droplets (8.86%±5.02%, P &lt; 0.01) compared to the patients without double-headed spermatozoa. Moreover, the percentage of sperm with multiple defects in the double-headed group was significantly higher (35.53%±29.91%, P &lt; 0.01), while the percentage of normal forms was significantly lower (2.93%±3.64%, P &lt; 0.01) compared to the patients without double heads. Limitations, reasons for caution In this study unequal sample sized groups were compared. We also need to investigate whether the obtained results will be confirmed in patients with certain pathological states, such as oligozoospermia, teratozoospermia, and asthenozoospermia. Wider implications of the findings: The present study revealed that the presence of double-headed spermatozoa in the ejaculate is related to an increased frequency of the other semen abnormalities. The double-headed spermatozoa could be used as an indicator for the total morphological quality of human spermatozoa Trial registration number Not applicable

Detecting Ozone- and Greenhouse Gas–Driven Wind Trends with Observational Data

Science ◽  
2013 ◽  
Vol 339 (6119) ◽  
pp. 563-567 ◽  
Author(s):  
Sukyoung Lee ◽  
Steven B. Feldstein
Keyword(s):  
Greenhouse Gas ◽  
Observational Data ◽  
Ozone Depletion ◽  
Austral Summer ◽  
Tropical Convection ◽  
The Other ◽  
Frequency Of Occurrence ◽  
Westerly Jet ◽  
Poleward Shift ◽  
Antarctic Ozone

Modeling studies suggest that Antarctic ozone depletion and, to a lesser degree, greenhouse gas (GHG) increase have caused the observed poleward shift in the westerly jet during the austral summer. Similar studies have not been performed previously with observational data because of difficulties in separating the two contributions. By applying a cluster analysis to daily ERA-Interim data, we found two 7- to 11-day wind clusters, one resembling the models' responses to GHG forcing and the other resembling ozone depletion. The trends in the clusters' frequency of occurrence indicate that the ozone contributed about 50% more than GHG toward the jet shift, supporting the modeling results. Moreover, tropical convection apparently plays an important role for the GHG-driven trend.

Porównanie częstości występowania objawów współistniejących w grupie pacjentów z zawrotami głowy

2017 ◽  
Vol 71 (1) ◽  
pp. 34-39
Author(s):  
Jakub Šichnárek ◽  
Jana Vyskotová ◽  
Kateřina Macháčková ◽  
Eva Mrázková
Keyword(s):  
Otitis Media ◽  
Multidisciplinary Approach ◽  
The Other ◽  
Frequency Of Occurrence ◽  
Impaired Hearing ◽  
Effective Solution ◽  
Significant Difference ◽  
Balance Disorder ◽  
Mild Obesity ◽  
Analyze Data

BACKGROUND: Dizziness is the second most frequent symptom that make patients seek specialized examination. The effective solution of dizzy conditions requires treatment in cooperation with different branches of medicine. OBJECTIVE: To analyze data from the database of patients with vertigo examined in the Hearing and Balance Disorder Centre in Ostrava, to find out whether, and in what factors, the sets of patients with diagnosed central and peripheral vestibular syndrom differ from each other. METHODS: Retrospective study that was carried out from October 2012 to February 2013. The data was gathered from documentation of all vertiginous patients who were examined by an otoneurologist. RESULTS: The statistically significant difference between the two sets was found in: occurrence of hypertension and mild obesity, impaired hearing and otitis media, stabilometric testing CONCLUSIONS: There was a statistically significant difference between the sets with the central and peripheral vestibular syndrome in the frequency of occurrence of hypertension, impaired hearing, otitis media, in mild obesity categorization and in balance disorders. There was not any statistically significant difference found in the other observed factors. The results confirm the need of a multidisciplinary approach to patients with vertigo.

scholarly journals The Assessment of Overall Hangover Severity

2020 ◽  
Vol 9 (3) ◽  
pp. 786 ◽  
Author(s):  
Joris C Verster ◽  
Aurora J.A.E. van de Loo ◽  
Sarah Benson ◽  
Andrew Scholey ◽  
Ann-Kathrin Stock
Keyword(s):  
Symptom Score ◽  
Primary Endpoint ◽  
Physical Functioning ◽  
False Positives ◽  
The Other ◽  
Average Score ◽  
Frequency Of Occurrence ◽  
Severity Scale ◽  
Other Hand ◽  
Item Scale

The aim of this study was to critically evaluate and compare the different methods to assess overall hangover severity. Currently, there are three multi-item hangover scales that are commonly used for this purpose. All of them comprise a number of hangover symptoms for which an average score is calculated. These scales were compared to a single, 1-item scale assessing overall hangover severity. The results showed that the hangover symptom scales significantly underestimate (subjective) hangover severity, as assessed with a 1-item overall hangover severity scale. A possible reason for this could be that overall hangover severity varies, depending on the frequency of occurrence of individual symptoms included in the respective scale. In contrast, it can be assumed that, when completing a 1-item overall hangover scale, the rating includes all possible hangover symptoms and their impact on cognitive and physical functioning and mood, thus better reflecting the actually experienced hangover severity. On the other hand, solely relying on hangover symptom scales may yield false positives in subjects who report not having a hangover. When the average symptom score is greater than zero, this may lead to non-hungover subjects being categorized as having a hangover, as many of the somatic and psychological hangover symptoms may also be experienced without consuming alcohol (e.g., having a headache). Taken together, the current analyses suggest that a 1-item overall hangover score is superior to hangover symptom scales in accurately assessing overall hangover severity. We therefore recommend using a 1-item overall hangover rating as primary endpoint in future hangover studies that aim to assess overall hangover severity.

scholarly journals Aquatic plant community in porto primavera reservoir

2014 ◽  
Vol 32 (3) ◽  
pp. 467-473 ◽  
Author(s):  
R.L.C.M. Pitelli ◽  
R.A. Pitelli ◽  
C.J. Rodrigues ◽  
J.H.P. Dias
Keyword(s):  
Cluster Analysis ◽  
Aquatic Plants ◽  
Water Body ◽  
Eichhornia Crassipes ◽  
Aquatic Plant ◽  
Hydrilla Verticillata ◽  
The Other ◽  
Frequency Of Occurrence ◽  
Eichhornia Azurea ◽  
Large Populations

Aiming to identify the populations of aquatic plants present in the Porto Primavera reservoir and evaluate the behavior of Hydrilla verticillata colonization of this water body a survey was carried out in 2007. The data was based on presence or absence, only were assessed the presence or absence of the species and the data were subjected to cluster analysis to establish differences in distribution and occurrence of populations. The community of aquatic plants showed 24 species distributed in 16 botanical families. Cyperaceae and Pontederiaceae were the most representative in terms of species richness. The submerged macrophyte Hydrilla verticillata showed the highest frequency of occurrence in the water body, showing a different behavior from the other populations of the water body. Species like Eichhornia crassipes, Eichhornia azurea, Typha dominguensis and Oxycaryum cubense also showed different behavior in relation to other populations within the community, forming large populations in lagoons and backwater areas.

Species richness in helminth communities: the importance of multiple congeners

Parasitology ◽  
1992 ◽  
Vol 104 (1) ◽  
pp. 189-197 ◽  
Author(s):  
C. R. Kennedy ◽  
A. O. Bush
Keyword(s):  
Species Richness ◽  
The Other ◽  
Simultaneous Occurrence ◽  
Data Sets ◽  
Frequency Of Occurrence ◽  
Congeneric Species ◽  
Aquatic Birds ◽  
Component Community ◽  
Using Data ◽  
Species Flocks

SUMMARYUsing data sets derived from published literature, the contribution of congeneric species to helminth component community richness is evaluated. Consideration of the frequency distribution of congeners in relation to host and parasite groups reveals that the distributions are unimodal, that singletons are the commonest class and that the frequency of occurrence of congeners decreases with increasing number of species per genus. Congeners may be found in any group of hosts or parasites, but are more common amongst cestodes of aquatic birds. Two patterns of occurrence of congeneric species are recognized: one in which from a few to multiple congeners are found within a single helminth genus, exemplified by dactylogyrid monogeneans and cloacinid nematodes, and the other in which there is a simultaneous occurrence of congenerics and confamilials such that there are several genera involved, but each represented by fewer species, exemplified by strongyles in horses. The question of whether these patterns can be considered examples of species flocks is discussed. We conclude that multiple congeners and species flocks are interesting phenomena but, except in isolated cases, they make insignificant contributions to community richness.

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