scholarly journals The luminosity evolution of nova shells

2020 ◽  
Vol 641 ◽  
pp. A122
Author(s):  
C. Tappert ◽  
N. Vogt ◽  
A. Ederoclite ◽  
L. Schmidtobreick ◽  
M. Vučković ◽  
...  
Keyword(s):  
Light Curve ◽  
Cataclysmic Variables ◽  
General Behaviour ◽  
Curve Type ◽  
Formal Quality ◽  
Significant Difference ◽  
Nova Shells ◽  
Two Phases ◽  
Almost All ◽  
Luminosity Evolution

Over the last decade, nova shells have been discovered around a small number of cataclysmic variables that had not been known to be post-novae, while other searches around much larger samples have been mostly unsuccessful. This raises the question about how long such shells are detectable after the eruption and whether this time limit depends on the characteristics of the nova. So far, there has been only one comprehensive study of the luminosity evolution of nova shells, undertaken almost two decades ago. Here, we present a re-analysis of the Hα and [O III] flux data from that study, determining the luminosities while also taking into account newly available distances and extinction values, and including additional luminosity data of “ancient” nova shells. We compare the long-term behaviour with respect to nova speed class and light curve type. We find that, in general, the luminosity as a function of time can be described as consisting of three phases: an initial shallow logarithmic decline or constant behaviour, followed by a logarithmic main decline phase, with a possible return to a shallow decline or constancy at very late stages. The luminosity evolution in the first two phases is likely to be dominated by the expansion of the shell and the corresponding changes in volume and density, while for the older nova shells, the interaction with the interstellar medium comes into play. The slope of the main decline is very similar for almost all groups for a given emission line, but it is significantly steeper for [O III], compared to Hα, which we attribute to the more efficient cooling provided by the forbidden lines. The recurrent novae are among the notable exceptions, along with the plateau light curve type novae and the nova V838 Her. We speculate that this is due to the presence of denser material, possibly in the form of remnants from previous nova eruptions, or of planetary nebulae, which might also explain some of the brighter ancient nova shells. While there is no significant difference in the formal quality of the fits to the decline when grouped according to light curve type or to speed class, the former presents less systematic scatter. It is also found to be advantageous in identifying points that would otherwise distort the general behaviour. As a by-product of our study, we revised the identification of all novae included in our investigation with sources in the Gaia Data Release 2 catalogue.

Transformative Learning in Mastery-Oriented CS0 Course

2021 ◽  
pp. 234763112110072
Author(s):  
Srinivasan Lakshminarayanan ◽  
N. J. Rao ◽  
G. K. Meghana
Keyword(s):  
Transformative Learning ◽  
First Year ◽  
Guided Discovery ◽  
Engineering Programs ◽  
Transformative Experiences ◽  
Significant Difference ◽  
Cognitive Levels ◽  
Almost All ◽  
Core Course

The introductory programming course, commonly known as CS1 and offered as a core course in the first year in all engineering programs in India, is unique because it can address higher cognitive levels, metacognition and some aspects of the affective domain. It can provide much needed transformative experiences to students coming from a system of school education that is dominantly performance-driven. Unfortunately, the CS1 course, as practiced in almost all engineering programs, is also performance-driven because of a variety of compulsions. This paper suggests that the inclusion of a course CS0 can bring about transformative learning that can potentially make a significant difference in the quality of learning in all subsequent engineering courses. The suggested instruction design of this course takes the advantage of the unique features of a course in programming. The proposed CS0 course uses “extreme apprenticeship” and “guided discovery” methods of instruction. The effectiveness of these instruction methods was established through the use of the thematic analysis, a well-known qualitative research method, and the associated coding of transformative learning experiences and instruction components.

scholarly journals Development and Evaluation of Direct Paddy Seeder in Puddled Field

2021 ◽  
Vol 13 (5) ◽  
pp. 2745
Author(s):  
Manoj Kumar ◽  
Ritu Dogra ◽  
Mahesh Narang ◽  
Manjit Singh ◽  
Sushant Mehan
Keyword(s):  
Laboratory Testing ◽  
Field Evaluation ◽  
Row Spacing ◽  
Second Phase ◽  
Cell Type ◽  
Inclined Plate ◽  
Seed Damage ◽  
Two Phases ◽  
Almost All ◽  
Different Soils

Manual transplanting, a pre-dominant practice in almost all the paddy growing areas in India, is laborious, burdensome, and has many expenses on raising, settling, and transplanting nursery. The transplanting process’s limitations motivated the replacement of conventional paddy transplanting methods. The study was divided into two phases. The first phase included laboratory testing of three levels of metering mechanisms, namely cell type (M1) with 10 cells grooved around a circular plate having a 13 cm diameter, inclined plate (M2) containing 24 U shaped cells provided on an 18 cm diameter plate, and fluted roller (M3) with 10 flutes on a 5 cm diameter shaft. The testing matrix included a missing index, multiple index, and seed damage with forward speeds (2.5, 3.0, and 3.5 km/h), and pre-germination levels of 24 h soaked (P1), 24 h pre-germinated (P2), and 36 h pre-germinated paddy seeds (P3)). The second phase included selecting the best combination obtained from the laboratory study and developing a new efficient planter for the puddled field. The inclined plate metering mechanism operating at 2.5 km/h for 24 h pre-germinated seeds was reported most efficient from the first phase. Therefore, a self-propelled 8-row planter equipped with an inclined plate metering mechanism having a row-to-row spacing of 22.5 cm was developed, fabricated, and evaluated in the puddled field. The designed planter was assessed on two different soils: sandy loom (ST1) and clay loom (ST2) and at two different hopper fill levels as ½ filled hopper (F1) and ¾ filled hopper (F2). The number of plants per square meter and hill-to-hill spacing was measured. The on-field evaluation revealed that the number of plants per square meter was non-significantly affected by the type of soil but was significantly affected by hopper fill.

Do Deeper Levels of Cervical Biopsies Preceded by a Pap Smear Diagnosis of LSIL, ASCUS, or NILM/HPV+ Increase the Yield of Identifying Clinically Significant Lesions?

2020 ◽  
Vol 154 (Supplement_1) ◽  
pp. S163-S164
Author(s):  
K G Manjee ◽  
W G Watkin
Keyword(s):  
Pap Smear ◽  
Past History ◽  
Prior History ◽  
Cervical Biopsy ◽  
P16 Immunohistochemistry ◽  
Hpv Status ◽  
Significant Difference ◽  
History Of ◽  
Clinically Significant ◽  
Almost All

Abstract Introduction/Objective Cervical biopsy is performed following an abnormal pap smear or positive HPV testing in an attempt to uncover clinically significant lesions [HSIL/invasive carcinoma (HSIL+)]. An excisional procedure is considered if biopsy confirms HSIL+. When preceded by pap smear of LSIL, ASCUS, NILM/HPV+ or persistent HPV, continued surveillance is recommended for biopsies showing no SIL or LSIL. In our laboratory, cervical biopsies are routinely sectioned at 3 levels. Deeper levels are often ordered when initial sections are non-diagnostic. p16 immunohistochemistry, with or without deeper levels, is often ordered to confirm HSIL, or to differentiate HSIL from mimics. In this study, we examine whether and in what clinical situations does obtaining additional levels uncover clinically significant lesions. Methods 430 cervical biopsies between January-May 2018, with recent cytology of LSIL, ASCUS or NILM/HPV+ were identified in the pathology database. HPV status (if known), final biopsy diagnosis and past history of LSIL/HSIL were recorded. For each biopsy, orders for additional levels and/or p16 immunohistochemistry were recorded resulting in 4 categories: C1-no additional levels or p16, C2-deeper only, C3-deeper+p16 and C4-p16 only. Final diagnoses were divided into HSIL+, LSIL and no SIL. Results There was no significant difference in prior history of LSIL/HSIL and HPV status between all categories. Biopsy results were as follows: HSIL+: 11/222 (5%) C1; 1/78 (1%) C2; 7/43 (16%) C3; 15/87 (17%) C4 LSIL: 91/222 (41%) C1; 7/78 (9%) C2; 16/43 (37%) C3; 35/87 (40%) C4 No SIL: 120/222 (54%) C1; 70/78 (90%) C2; 20/43 (46%) C3; 37/87 (42%) C4 The average number of additional levels in C2 and C3 was 3.8 and 1.8, respectively. Conclusion Deeper levels alone did not enhance the detection of HSIL+. Almost all LSIL/HSIL were detected when initial levels were diagnostic or suspicious and supported by p16 immunohistochemistry. 3 levels are adequate to detect clinically significant lesions.

scholarly journals RT-PCR analysis of Deformed wing virus in honeybees (Apis mellifera) and mites (Varroa destructor)

2005 ◽  
Vol 86 (12) ◽  
pp. 3419-3424 ◽  
Author(s):  
Constanze Yue ◽  
Elke Genersch
Keyword(s):  
Varroa Destructor ◽  
Pcr Analysis ◽  
Body Parts ◽  
Rt Pcr ◽  
Larval Food ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
Significant Difference ◽  
Almost All ◽  
Viral Sequences

Deformed wing virus (DWV) is a honeybee viral pathogen either persisting as an inapparent infection or resulting in wing deformity. The occurrence of deformity is associated with the transmission of DWV through Varroa destructor during pupal stages. Such infections with DWV add to the pathology of V. destructor and play a major role in colony collapse in the course of varroosis. Using a recently developed RT-PCR protocol for the detection of DWV, individual bees and mites originating from hives differing in Varroa infestation levels and the occurrence of crippled bees were analysed. It was found that 100 % of both crippled and asymptomatic bees were positive for DWV. However, a significant difference in the spatial distribution of DWV between asymptomatic and crippled bees could be demonstrated: when analysing head, thorax and abdomen of crippled bees, all body parts were always strongly positive for viral sequences. In contrast, for asymptomatic bees viral sequences could be detected in RNA extracted from the thorax and/or abdomen but never in RNA extracted from the head. DWV replication was demonstrated in almost all DWV-positive body parts of infected bees. Analysing individual mites for the presence of DWV revealed that the percentage of DWV-positive mites differed between mite populations. In addition, it was demonstrated that DWV was able to replicate in some but not all mites. Interestingly, virus replication in mites was correlated with wing deformity. DWV was also detected in the larval food, implicating that in addition to transmission by V. destructor DWV is also transmitted by feeding.

How label and nutritional claims affect consumers’ acceptance, buying intention and quality perception toward a beverage made from cashew nut

2019 ◽  
Vol 49 (6) ◽  
pp. 1243-1251 ◽  
Author(s):  
Marina Cabral Rebouças ◽  
Maria do Carmo Passos Rodrigues ◽  
Silvia Maria de Freitas
Keyword(s):  
New Product ◽  
Quality Attributes ◽  
Attitude Scale ◽  
Content Type ◽  
Cashew Nut ◽  
Significant Difference ◽  
Perception Of Quality ◽  
Two Phases ◽  
Mango Juice ◽  
Hedonic Scale

Purpose The purpose of this paper is to evaluate the influence of the front of a package label and the nutritional claims linked to it over consumers’ expectations as to acceptance, purchase attitude and perception of quality characteristics of a new functional beverage made from cashew nut milk and added with mango juice and prebiotic substances. Design/methodology/approach Three versions of the front label were developed, which differed just by the type of nutritional claim presented (“0 per cent lactose and 0 per cent cholesterol; 0 per cent lactose, 0 per cent cholesterol and source of fibers, 0 per cent lactose, 0 per cent cholesterol and antioxidants”) and were evaluated in two phases, expectation and informed. For the evaluation, consumers used a multi-attribute scale, the nine-point hedonic scale and a nine-point semi-structured buying attitude scale. Findings The labels created a positive expectation on the consumers regarding the quality attributes, overall impression (mean = 6.0 “Like slightly”) and buying attitude (mean = 6.0 “Would probably buy”). After tasting the beverage associated with labels (informed phase), consumers kept a positive evaluation. The t-test performed between the pair of means of both phases showed that there has not been a significant difference regarding the quality attributes (p > 0.05), special, attractive, nutritive, healthy and buying attitude (Label 1, p = 0.26; Label 2, p = 0.18; Label 3, p = 0.26) in all labels. Originality/value The authors evaluated how the influence of label and nutritional claims in regards to a new product, a beverage made from cashew nut, affects its acceptance, buying attitude and characteristics of quality. Until this moment, there are no studies that evaluate how external attributes affect the acceptance of this beverage totally unique in the Brazilian market.

scholarly journals Intermittent maser flare around the high-mass young stellar object G353.273+0.641

2012 ◽  
Vol 8 (S287) ◽  
pp. 98-102
Author(s):  
Kazuhito Motogi ◽  
Kazuo Sorai ◽  
Kenta Fujisawa ◽  
Koichiro Sugiyama ◽  
Mareki Honma
Keyword(s):  
Light Curve ◽  
Small Area ◽  
Linear Acceleration ◽  
High Mass ◽  
Velocity Range ◽  
Time Resolved ◽  
Almost All ◽  
Maser Sources ◽  
Water Maser

AbstractThe water maser site associated with G353.273+0.641 is classified as a dominant blueshifted H2O maser, which shows an extremely wide velocity range (± 100 km s−1) with almost all flux concentrated in the highly blueshifted emission. The previous study has proposed that this peculiar H2O maser site is excited by a pole-on jet from high mass protostellar object. We report on the monitoring of 22-GHz H2O maser emission from G353.273+0.641 with the VLBI Exploration of Radio Astrometry (VERA) and the Tomakamai 11-m radio telescope. Our VLBI imaging has shown that all maser features are distributed within a very small area of 200 × 200 au2, in spite of the wide velocity range (> 100 km s−1). The light curve obtained by weekly single-dish monitoring shows notably intermittent variation. We have detected three maser flares during three years. Frequent VLBI monitoring has revealed that these flare activities have been accompanied by a significant change of the maser alignments. We have also detected synchronized linear acceleration (−5 km s−1yr−1) of two isolated velocity components, suggesting a lower-limit momentum rate of 10−3 M⊙ km s−1yr−1 for the maser acceleration. All our results support the previously proposed pole-on jet scenario, and finally, a radio jet itself has been detected in our follow-up ATCA observation. If highly intermittent maser flares directly reflect episodic jet-launchings, G353.273+0.641 and similar dominant blueshifted water maser sources can be suitable targets for a time-resolved study of high mass protostellar jet.

scholarly journals DIFFERENT APPROACHES OF CLIENTS AND CONSULTANTS TO CONTRACTORS’ QUALIFICATION AND SELECTION

2005 ◽  
Vol 11 (4) ◽  
pp. 267-276 ◽  
Author(s):  
Mehmedali Egemen ◽  
Abdulrezak N. Mohamed
Keyword(s):  
Construction Industry ◽  
Selection Processes ◽  
Significant Difference ◽  
Different Types ◽  
Almost All ◽  
High Willingness

Nowadays, clients are the dominant groups in almost all types of industries. However, the construction industry is unique and consultants, as representatives of clients, are very important figures in this industry as well. By presenting survey findings of 91 clients and 50 consultants, this study reveals clients’ and consultants’ differing expectations of contracting organisations during contractor qualification and selection. The study has clearly confirmed the fact that consultants’ perspectives are rather different and their contractors’ expectations of their clients vary very significantly from the clients themselves. Furthermore, significantly different results were found even among different types of consultants and different categories of clients. Moreover, this study showed that both clients and consultants had high willingness to continue working with the same contractor in possible future works assuming they are satisfied with the previous works. The criteria, which contribute to achieving full client and/or consultant satisfaction and hence lead to possible repetitive works are identified and the results showed the existence of significant difference between clients and consultants perspectives regarding this issue as well. The framework presented within this paper aims to help the contracting organisations to compare and recognise the different approaches and perceptions of both clients and consultants during contractor qualification and selection processes. The contracting organisations in the related sectors will be able to use the framework provided within this study to recognise the overall demand in a more complete and better manner and hence formulate or modify strategies accordingly.

scholarly journals Effectiveness of Environmentally Friendly Mosquito Trap Contained Sugar Yeast Solution

2017 ◽  
Vol 12 (2) ◽  
pp. 270-276 ◽  
Author(s):  
Tutik Ida Rosanti ◽  
S Juwono Mardihusodo ◽  
Wayan T Artama
Keyword(s):  
Experimental Design ◽  
Environmentally Friendly ◽  
P Value ◽  
Mosquito Trap ◽  
Significant Difference ◽  
Rank Score ◽  
Quasi Experimental ◽  
Two Phases ◽  
Materials Used ◽  
Indoor And Outdoor

Environmentally friendly mosquitoes trap using common daily materials used by community may give hopes in reducing mosquitoes density. This study aims to determine the effectiveness of environmentally friendly mosquitoes trap made from bottle contained sugar yeast solution for reducing the number of trapped mosquitoes. This study consist of two phases and quasi experimental design was used. Mann Whitney test was used to determine the differences the number of trapped mosquitoes indoor and outdoor. The result showed p value 0,000 which was lower than ? value (0,05), so there was significant difference between the number of indoor and outdoor trapped mosquitoes. The average Rank score of outdoor mosquitoes trap (42,75) was more than indoor mosquitoes trap (18,25). We concluded that the mosquitoes trapped which contained of sugar-yeast solution was effective for trapping the mosquitoes especially outdoor .

scholarly journals Evaluation of the relationship between MIH severity and dental fear among the children

2019 ◽  
Vol 6 (10) ◽  
pp. 284-287
Author(s):  
Can Özükoç
Keyword(s):  
Behavioral Problems ◽  
Dental Anxiety ◽  
Pediatric Dentistry ◽  
Dental Fear ◽  
Common Condition ◽  
Molar Incisor Hypomineralization ◽  
Significant Difference ◽  
Fear Survey Schedule ◽  
Almost All ◽  
The Relationship

Objective: Molar incisor hypomineralization (MIH), a quite common condition in pediatric dentistry, whose treatment might seem complicated, manifests itself with severe dental anxiety and fear that can cause behavioral problems. Although dental fear is seen in almost all cases, it is believed that dental fear will increase as the severity of MIH increases. This study evaluates the relationship between MIH severity and dental fear. Material and Methods: Children Fear Survey Schedule-Dental Subscale (CFSS-DS) was used to measure dental fear in 58 (51.79%) children whose teeth suffered from mild, moderate or severe MIH and 54 (48.21%) children with healthy teeth. Scores between 1 (not afraid at all) and 5 (very afraid) were given according to the responses. Each question was evaluated separately in order to obtain the total score. Results: Children with severe MIH who participated in the study were proved to be more afraid of the dentists, drill sounds, injections, placement of instruments in the mouth, choking and going to the hospital; and there was a statistically significant difference (p<0.05). Conclusion: Although it was observed that the severity of MIH and dental fear are correlated and dental fear increases with the increase in the MIH severity, further studies in this subject are necessary.

scholarly journals Periodically and quasi-periodically driven dynamics of Bose-Einstein condensates

2020 ◽  
Vol 9 (5) ◽  
Author(s):  
Pengfei Zhang ◽  
Yingfei Gu
Keyword(s):  
Phase Boundary ◽  
Quantum Dynamics ◽  
Scattering Length ◽  
Finite Measure ◽  
Sine Wave ◽  
Square Wave ◽  
Periodically Driven ◽  
Two Phases ◽  
Almost All ◽  
Bose Einstein

We study the quantum dynamics of Bose-Einstein condensates when the scattering length is modulated periodically or quasi-periodically in time within the Bogoliubov framework. For the periodically driven case, we consider two protocols where the modulation is a square-wave or a sine-wave. In both protocols for each fixed momentum, there are heating and non-heating phases, and a phase boundary between them. The two phases are distinguished by whether the number of excited particles grows exponentially or not. For the quasi-periodically driven case, we again consider two protocols: the square-wave quasi-periodicity, where the excitations are generated for almost all parameters as an analog of the Fibonacci-type quasi-crystal; and the sine-wave quasi-periodicity, where there is a finite measure parameter regime for the non-heating phase. We also plot the analogs of the Hofstadter butterfly for both protocols.

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