scholarly journals Photometric characteristics of the Be stars: almost twenty years of UBV monitoring at the Hvar observatory

1994 ◽  
Vol 162 ◽  
pp. 301-302
Author(s):  
K. Pavlovski ◽  
H. Božić ◽  
Ž. Ružić ◽  
P. Harmanec ◽  
J. Horn ◽  
...  
Keyword(s):  
Be Stars ◽  
Photoelectric Photometry ◽  
Ample Evidence ◽  
Large Group ◽  
Almost All ◽  
By Products

Since their discovery (by Father Secchi in 1866) until the end of sixties, Be stars were not a subject of any systematic studies of their possible light and colour variations. Already at that time, the astronomical literature contained ample evidence showing that a number of Be stars were light variables. However, almost all such findings resulted as by-products of studies of different or wider groups of objects. Feinstein (1968) was probably the first who pointed out explicitly that many Be stars are light variables. A pioneering study which was aimed at the detection of light variations of a large group of Be stars by means of differential photoelectric photometry was carried out by Haupt & Schroll (1974).

scholarly journals System Analysis of Biogas Production—Part II Application in Food Industry Systems

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 412 ◽  
Author(s):  
Emma Lindkvist ◽  
Magnus Karlsson ◽  
Jenny Ivner
Keyword(s):  
Food Industry ◽  
System Analysis ◽  
Animal Feed ◽  
Biogas Production ◽  
Treatment Method ◽  
Energy And Environment ◽  
Efficient Alternative ◽  
Almost All ◽  
Business As Usual ◽  
By Products

Biogas production from organic by-products is a way to recover energy and nutrients. However, biogas production is not the only possible conversion alternative for these by-products, and hence there is interest in studying how organic by-products are treated today and which alternatives for conversion are the most resource efficient from a systems perspective. This paper investigates if biogas production is a resource efficient alternative, compared to business as usual, to treat food industry by-products, and if so, under what circumstances. Five different cases of food industries were studied, all with different prerequisites. For all cases, three different scenarios were analysed. The first scenario is the business as usual (Scenario BAU), where the by-products currently are either incinerated, used as animal feed or compost. The second and third scenarios are potential biogas scenarios where biogas is either used as vehicle fuel (Scenario Vehicle) or to produce heat and power (Scenario CHP). All scenarios, and consequently, all cases have been analysed from three different perspectives: Economy, energy, and environment. The environmental perspective was divided into Global Warming Potential (GWP), Acidification Potential (AP), and Eutrophication Potential (EP). The results show, in almost all the systems, that it would be more resource efficient to change the treatment method from Scenario BAU to one of the biogas scenarios. This paper concludes that both the perspective in focus and the case at hand are vital for deciding whether biogas production is the best option to treat industrial organic by-products. The results suggest that the food industry should not be the only actor involved in deciding how to treat its by-products.

scholarly journals Composite Colour-Magnitude and Colour-Colour Diagrams for Be Stars in Open Clusters

1982 ◽  
Vol 98 ◽  
pp. 23-26
Author(s):  
J.-C. Mermilliod
Keyword(s):  
Age Groups ◽  
Open Clusters ◽  
Be Stars ◽  
Photoelectric Photometry ◽  
Absolute Magnitudes ◽  
Colour Indices

By the end of 1980, the total number of Be stars discovered in the field of open clusters amounted to 180 stars distributed in 60 clusters. Among these, 110 Be stars belong to 32 clusters included in the sample I studied, which contains 75 open clusters younger than the Hyades. But only 88 stars with complete UBV photoelectric photometry have been taken into consideration here. The concept of age groups, defined elsewhere (Mermilliod 1981a), is used throughout the present analysis, as well as the new estimate of the colour excesses and distance moduli I obtained for these 32 clusters. Under the assumption of uniform reddening across the clusters, absolute magnitudes and dereddened colour indices have been calculated for the 88 Be stars.

scholarly journals Be Star Surveys in Open Clusters with Balmer-line Photometry

2000 ◽  
Vol 175 ◽  
pp. 63-66
Author(s):  
Gemma Capilla ◽  
Juan Fabregat ◽  
Deborah Baines
Keyword(s):  
Emission Line ◽  
Main Sequence ◽  
Open Clusters ◽  
Balmer Line ◽  
Be Stars ◽  
Late Type ◽  
Efficient Tool ◽  
Be Star ◽  
Almost All ◽  
Evolutionary Interpretation

AbstractWe present CCD Hα and Hβ photometry of young open clusters. We show that the comparison of the α and β photometric indices provides an efficient tool for identifying emission line stars. We report on the discovery of several new Be stars.The preliminary results of our survey are the following: i. the younger clusters (age < 10 Myr) are almost lacking of Be stars, ii. clusters in the age interval 10–30 Myr are rich in Be stars. Almost all of them are of spectral types earlier than B5, while late-type Be stars are scarce. These results point towards an evolutionary interpretation of the Be phenomenon, in the sense that Be stars are close to the end of their main sequence lifetime.

Artificial intelligence in brachytherapy: a summary of recent developments

2021 ◽  
pp. 20200842
Author(s):  
Susovan Banerjee ◽  
Shikha Goyal ◽  
Saumyaranjan Mishra ◽  
Deepak Gupta ◽  
Shyam Singh Bisht ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
External Beam Radiotherapy ◽  
Intensity Modulated Radiotherapy ◽  
External Beam ◽  
Human Errors ◽  
Ample Evidence ◽  
Recent Developments ◽  
Human Effort ◽  
Almost All ◽  
Direct Use

Artificial intelligence (AI) applications, in the form of machine learning and deep learning, are being incorporated into practice in various aspects of medicine, including radiation oncology. Ample evidence from recent publications explores its utility and future use in external beam radiotherapy. However, the discussion on its role in brachytherapy is sparse. This article summarizes available current literature and discusses potential uses of AI in brachytherapy, including future directions. AI has been applied for brachytherapy procedures during almost all steps, starting from decision-making till treatment completion. AI use has led to improvement in efficiency and accuracy by reducing the human errors and saving time in certain aspects. Apart from direct use in brachytherapy, AI also contributes to contemporary advancements in radiology and associated sciences that can affect brachytherapy decisions and treatment. There is a renewal of interest in brachytherapy as a technique in recent years, contributed largely by the understanding that contemporary advances such as intensity modulated radiotherapy and stereotactic external beam radiotherapy cannot match the geometric gains and conformality of brachytherapy, and the integrated efforts of international brachytherapy societies to promote brachytherapy training and awareness. Use of AI technologies may consolidate it further by reducing human effort and time. Prospective validation over larger studies and incorporation of AI technologies for a larger patient population would help improve the efficiency and acceptance of brachytherapy. The enthusiasm favoring AI needs to be balanced against the short duration and quantum of experience with AI in limited patient subsets, need for constant learning and re-learning to train the AI algorithms, and the inevitability of humans having to take responsibility for the correctness and safety of treatments.

scholarly journals An Assessment of Current and Past Concentrations of Trihalomethanes in Drinking Water throughout France

2018 ◽  
Vol 15 (8) ◽  
pp. 1669 ◽  
Author(s):  
Magali Corso ◽  
Catherine Galey ◽  
René Seux ◽  
Pascal Beaudeau
Keyword(s):  
Surface Water ◽  
Natural Organic Matter ◽  
Tap Water ◽  
Original Method ◽  
French Population ◽  
The Past ◽  
Water Origin ◽  
Almost All ◽  
Water Treatments ◽  
By Products

In France, 95% of people are supplied with chlorinated tap water. Due to the presence of natural organic matter that reacts with chlorine, the concentrations of chlorination by-products (CBPs) are much higher in chlorinated water produced from surface water than from groundwater. Surface water supplies 33% of the French population. Until the 1980s, almost all surface water utilities pre-chlorinated water at the intake. Pre-chlorination was then gradually banned from 1980 to 2000. Trihalomethanes (THMs) are the only regulated CBP in France. Since 2003, THMs have been monitored at the outlet of all utilities. This study assessed current (2005–2011) and past (1960–2000) exposure of the French population to THMs. We developed an original method to model THM concentrations between 1960 and 2000 according to current concentrations of THMs, concentration of total organic carbon in raw and finished water, and the evolution of water treatments from 1960 onward. Current and past mean exposure of the French population to THMs was estimated at 11.7 µg·L−1 and 17.3 µg·L−1, respectively. In the past, approximately 10% of the French population was exposed to concentrations >50 µg·L−1 vs. 1% currently. Large variations in exposure were observed among France’s 100 administrative districts, mainly depending on the water origin (i.e., surface vs. ground), ranging between 0.2 and 122.1 µg·L−1 versus between 1.8 and 38.6 µg·L−1 currently.

Evaluation of nanofiltration for disinfection by-products control in drinking water treatment

2001 ◽  
Vol 1 (5-6) ◽  
pp. 233-243 ◽  
Author(s):  
M. Itoh ◽  
S. Kunikane ◽  
Y. Magara
Keyword(s):  
Molecular Weight ◽  
River Water ◽  
High Performance ◽  
Membrane Surface ◽  
Drinking Water Treatment ◽  
Apparent Molecular Weight ◽  
Distribution Patterns ◽  
Low Concentrations ◽  
Almost All ◽  
By Products

DBP control by nanofiltration was studied. Nine DBPs including THMs were selected as target compounds. Reagent DBPs and DBPs formed as a result of chlorination of NOM contained in river water, were applied to nanofiltration to examine DBPs removal. Humic acid was used to investigate DBP precursor control. Nanofiltration was conducted for about one day for each experiment using two 2-inch membrane modules. NF showed high performance for DBP precursor removal but little effect on the removal of DBPs themselves, especially THMs. In the experiment of DBP precursors removal, rejections were 98 to 100 percent for most of the DBPFPs. For NOM in river water, rejections of THMFPs were 96 to 99 percent. This shows nanofiltration is effective even at low concentrations of NOM. Nanofiltration can remove almost all organic substances with the apparent molecular weight of greater than 2,000 daltons. Molecular weight distribution patterns of the permeate were different depending on NF. THMs showed decreasing rejection as filtration proceeded because of adsorption on the membrane surface. THM rejections at 24 hours after filtration started were about 10 and 30 percent in Module-A and B, respectively. Haloacetic acids showed relatively higher rejections. It is recommended, from the viewpoint of THM control, that NOM removal using NF is much preferable to the removals of THM, formed by chlorination, using NF.

scholarly journals RUBBERISED COIR INDUSTRY - AN INTRODUCTION

CORD ◽  
1988 ◽  
Vol 4 (01) ◽  
pp. 34
Author(s):  
P. Chandy Mathew
Keyword(s):  
Coconut Palm ◽  
Value Addition ◽  
Coconut Tree ◽  
Coconut Kernel ◽  
Coconut Fibre ◽  
Almost All ◽  
Capital Intensive ◽  
By Products

The coconut palm is one of the versatile products of nature. Almost all parts of the tree are put to use by man. The uses of coconut kernel, shell, husk, trunk, leaves, sap etc., are well known and are therefore not described here. In this paper only one aspect of utilisation of coconut namely coconut fibre or coir for production of rubberised fibre is discussed in some detail. In major coconut producing areas more attention is given to utilisation of coconut kernel as this represents the most valuable portion of the coconut tree. It is therefore quite natural that most people con­cemed with coconut production and processing are less familiar with the by‑products of coconut. One such by‑product is rubber­ised coir which is a relatively capital intensive industry. In terms of "value addition" the production of rubberised coir is one of the top industries in the coconut and by‑product industries. This paper is an introduction to some aspects of rubberised coir.

scholarly journals Perception and Management of COVID-19 Among Allergic Children: An Italian Survey.

2020 ◽  
Author(s):  
Lucia Diaferio ◽  
Giuseppe Fabio Parisi ◽  
Giulia Brindisi ◽  
Cristiana Indolfi ◽  
Giuseppe Marchese ◽  
...  
Keyword(s):  
Good Practice ◽  
Geographical Area ◽  
Point Of View ◽  
Ample Evidence ◽  
The North ◽  
Allergy And Immunology ◽  
North Part ◽  
Risk Of Disease ◽  
Asthma And Allergy ◽  
Almost All

Abstract Background There is ample evidence that COVID-19 is significantly less severe in children than in adults and it has been reported that asthma and allergy, the most prevalent chronic disorders in children, are not included in the top 10 comorbidities associated with COVID-19 fatalities. Nevertheless, there would seem that the concerns about asthma and the risk of disease and related outcomes are still high. In order to assess these features, we conducted a 20-question anonymous internet-based survey among Italian paediatricians. Methods The questionnaire was conceived and pretested in April 2020, by a working group of experts of the Italian Paediatric Society for Allergy and Immunology (SIAIP). The survey was emailed once between April and mid-May 2020. Participants were allowed to complete only a single survey.Results A total 99 participants had taken part in our survey and provided responses to our electronic questionnaire. The distribution of patients reported per month varies significantly according to the geographical area (P=0.02). Data confirmed that in the North part of Italy the rate of patients referred is higher than in the rest of Italy. Almost all respondents (98%) reported caring for up to a maximum of 10 infecting children and the last 2% more than twenty. Among these patients, according to the 75% of responders, a maximum rate of 20% were affected by allergic rhino-conjunctivitis and in particular in the North of Italy while in the Centre and in the South there was a higher incidence (P=0.09). Almost the same applies for asthma, 83% of responders declared that up to a maximum of 20% of affected children were asthmatic, from 20% to 40% for the 13,5% of responders and from 40% to 60% for the last 3,5%. As for the allergic conjunctivitis also for asthma, we found a higher incidence in the Centre and in South than in the North (P=0.03).Conclusions This study is the first to provide a comprehensive review of COVID-19 knowledge and perceptions among paediatricians in Italy. From our point of view, it provides important information clearly useful for improving a good practice.

scholarly journals Photospheric Activity in Selected Be Stars: λ Eri and γ Cas

1994 ◽  
Vol 162 ◽  
pp. 241-253
Author(s):  
Myron A. Smith
Keyword(s):  
X Rays ◽  
Be Stars ◽  
Process Thought ◽  
Almost All

Recent observations of rapid variations in optical He I lines, X-rays, and FUV wavelengths in the prototypical classical Be stars λ Eri and star γ Cas hint that the violent processes occur on the surfaces of these stars almost all the time. We suggest that of these phenomena show greater similarities with magnetic flaring than any other process thought to occur on stars.

scholarly journals Line Profile Variations of Rotating Pulsating Stars

1993 ◽  
Vol 139 ◽  
pp. 182-182
Author(s):  
C. Aerts ◽  
M. De Pauw
Keyword(s):  
Line Profile ◽  
Be Stars ◽  
Line Profiles ◽  
Rotating Stars ◽  
Early Type ◽  
Pulsating Stars ◽  
Doppler Image ◽  
Early Type Stars ◽  
Almost All ◽  
High Degree

Line-profile variations (LPVs) are often seen in early-type stars. They were first detected in the β Cephei stars, where they are due to radial as well as to nonradial pulsations (NRP). It is still a matter of debate whether NRP is also the cause of LPVs in broad-lined B- and Be stars.The study of LPVs of nonradially pulsating stars is often considered to be especially interesting in the case of rapid rotators, because in such stars the line profiles may offer a Doppler image of the stellar surface. Almost all investigators conclude that only sectorial modes with high -values can properly account for the observations of LPVs in broad-lined stars; on the other hand, high-degree modes are almost never seen in slowly rotating stars.We point out here that the expression for the velocity field which is usually adopted, is not valid for rapid rotators.

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