| 241. |
- Nilsson, Kerstin, et al.
(författare)
-
Occupational Injuries to Senior Farmers in Sweden
- 2010
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Ingår i: Journal of Agricultural Safety and Health. - 1074-7583. ; 16, s. 19-29
-
Tidskriftsartikel (refereegranskat)abstract
- The prevailing demographic change in the western world means that the workforce is becoming older. Farmers in particular often work beyond the normal retirement age, in a challenging physical environment. For example, the agricultural sector has the most hazardous work environment in Sweden. Therefore, it is interesting to examine the following questions: Are senior farmers more frequently involved in work-related injuries? Do some injuries happen more often in the oldest age group? Which part of the body is most frequently affected in different age groups? What can be done to decrease the risk of injury in senior farmers?
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| 242. |
- Nilsson, Kerstin, et al.
(författare, creator_code:000000023193205X_t)
-
Sustainable Healthy Working Life for All Ages—Work Environment, Age Management and Employability
- 2023
-
Ingår i: International Journal of Environmental Research and Public Health. - : MDPI Multidisciplinary Digital Publishing Institute. - 1661-7827 .- 1660-4601. ; 20:3
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- The proportion of elderly citizens is continuously increasing in most of the industrial world [1,2,3]. The current demographic trend is characterised by increased longevity and lower fertility rates, resulting in an increasingly ageing population. The retirement age in many countries is being postponed adapting the economic and budgetary implications of increased longevity to the new demographic distribution. Older people are encouraged to continue working and to participate in the labour force for as long as possible [1,2,3]. The demographic situation stresses the importance of factors that motivate older employees and self-employed individuals to keep working and maintain their employability until an older age, as well as encouraging the organisations and enterprises to care for their employees’ employability until an age older than the current retirement age [4,5,6,7]. There are a lot of factors that influence risks and problems, as well as employability and a healthy and sustainable working life for all ages at the individual organisational/enterprise and society level. The complexity of these factors has been identified in research. To make this complexity more manageable and comprehensible, the SwAge model has been used to organize these complex factors contributing to a healthy and sustainable working life for all ages in nine different areas of impact and determination. There are nine determinant areas identified in the SwAge-model [4,5], which are: (1) self-rated health, diagnoses, functional diversity; (2) physical work environment; (3) mental work environment; (4) work schedule, work pace, time for recuperation; (5) personal finances, work ability, employability; (6) personal social environment and work–life balance; (7) work social environment, discrimination, leadership and age management; (8) motivation, stimulation and satisfaction with work tasks; (9) knowledge, skills, and competence (Figure 1). This Special Issue will contribute to the development of our theoretical and practical knowledge inthe domains that influence people’s working life.
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| 243. |
- Nilsson, Kerstin, et al.
(författare)
-
Why work farmers beyond 65?
- 2012
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Ingår i: Landskap, trädgård, jordbruk : rapportserie. - 1654-5427. ; 2012:16, s. 88-88
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 244. |
- Nilsson, Ulla, et al.
(författare)
-
Migrantarbete inom den gröna näringen
- 2012
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I såväl media som inom myndigheter och organisationer har det under de senaste åren i allt högre grad uppmärksammats att migrerande arbetskraft inom den gröna näringen eventuellt används på ett sätt som kan strida mot arbetsrättsliga och sociala regleringar. Olika beskrivningar har pekat på levnads- och arbetsförhållanden som starkt avviker från de normalt förekommande i svenskt arbetsliv och inte uppfyller arbetsmiljölagens minimikrav. Det har dessutom påpekats att de bristfälliga förhållandena för den migrerande arbetskraften riskerar att påverka den gröna näringen i stort på ett negativt sätt där näringsidkare tvingas in i en nedåtgående spiral av underbudskonkurrens. Avsikten med föreliggande kunskapsöversikt är att sammanställa den forskning som finns avseende olika arbetslivs- och arbetsmiljöaspekter på migrantarbete inom den gröna näringen inklusive juridiska aspekter och myndighetsutövning. I den gröna sektorn finns arbetsmiljörisker förknippade med olycksfall, ergonomisk belastning, och exponering för t.ex. kemiska och biologiska bekämpningsmedel. Migrantarbetare inom den gröna sektorn i Sverige kommer ibland från länder där ‖arbetsplatskulturen‖ innefattar ett annorlunda säkerhetstänkande jämfört med i Sverige. Väl i Sverige kan språket vara ett hinder för arbetaren att tillgodogöra sig muntlig och skriftlig information om arbetet, miljön, skyddsföreskrifter och möjliga risker. Låg utbildningsnivå kan utgöra ytterligare problem. Undermåliga bostäder tillhandahållna av arbetsgivaren har beskrivits. En del av problemet utgörs av dolt arbete som utförs av papperslösa. Projektledning och administration i projektet, som har tagit fram kunskapsöversikten, har legat hos Arbetsmiljöhögskolan (AMH) vid Lunds universitet, som är en nätverksorganisation som samlar kompetenser från universitetets olika fakulteter för en mångvetenskaplig belysning av kunskapsläget på området. Kunskapsöversikten utgörs till största delen av en litteraturstudie där relevant forskning på området har sökts i olika databaser; och av en uppföljning av referenslistor i artiklar och böcker. På grund av den flerdimensionella problematiken kring migrantarbetet inom den gröna sektorn har en mångdisciplinär forskargrupp satts samman för uppdraget. Detta innebär att vi kan belysa problematiken utifrån många olika perspektiv. Redan på ett tidigt stadium stod det emellertid klart att det inte existerar någon mer omfattande svensk forskning på området vilket innebär att mycket av de resonemang som förs i den här skriften vilar på internationella erfarenheter. För att trots allt kunna ge en bild av förhållandena i Sverige har vi valt att genomföra ett antal telefonintervjuer med aktörer på nyckelpositioner. Intervjuer har gjorts med rådgivare, intresseorganisationer, fackliga organisationer för anställda och arbetsgivare samt berörda myndigheter. Genom den internationella litteraturen står det klart att det finns en rad arbetslivsoch arbetsmiljöproblem vilka är specifika för migrantarbete på säsongsbasis inom den gröna näringen. Ett av de främsta problemen har att göra med de uppenbara svårigheterna att följa upp och kontrollera konsekvenser och effekter. Säsongsarbetet innebär att människor endast uppehåller sig i landet under en begränsad period. Därför är det svårt att slå fast långsiktiga effekter på arbetstagarnas hälsa. Ett annat grundläggande problem är att incitamentet för värdländerna att vidta åtgärder för att minimera arbetslivs- och arbetsmiljöproblem är tämligen svagt. Ofta har de personer som lider skada på grund av bristfällig arbetsmiljö återvänt till sina hemländer då hälsoeffekterna blivit tydliga. Den här problematiken illustreras exempelvis av att de som har valt att ratificera FN:s konvention om migrantarbetares rättigheter– vilket borgar 6 främst är nationer varifrån migrantarbetarna kommer. Varken Sverige eller någon annan medlemsstat i EU har anslutit sig till konventionen. Det går inte att utifrån befintlig kunskap avgöra antalet migrantarbetare som på säsongsbasis arbetar inom den gröna näringen. Intervjuer med företagare ger vid handen att det skulle kunna röra sig om omkring 2 000 personer per år inom trädgård och jordbruk. Men det finns anledning att misstänka att det verkliga antalet är större minst på grund av att företagarna får antas dra sig för att rapportera om migrantarbetare som saknar nödvändiga papper och som är anlitade som svart arbetskraft. Det finns god grund i den internationella forskningen att anta att många migrantarbetare inom den gröna näringen i Sverige lever och arbetar under oacceptabla förhållanden - bortom rättslig kontroll och insyn. Det handlar bland annat om undermåliga bostäder och bristande hygien, ökad olycksrisk, exponering för hälsovådliga kemikalier, ergonomiska problem, risk för hot och våld, diskriminering, trakasserier, brist på stöd från samhället såsom sjukvård och rättshjälp, långa arbetstider och låg lön. Intervjuerna som genomfördes med representanter för relevanta svenska organisationer och myndigheter antyder att vi har anledning att misstänka att migrantarbetare inom den gröna näringen i Sverige lever och arbetar med samma problem som migrantarbetare inom den gröna näringen i andra länder. Det faktum att problematiken potentiellt är svårartad gör att kunskapsbristen i Sverige blir särskilt allvarlig och organisationer vara stort.– inte– ny forskning behövs. Dessutom torde behovet av insatser från myndigheter
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| 245. |
- Nyholm, Anders, 1985-
(författare)
-
Bumpy light curves of interacting supernovae
- 2017
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A supernova (SN) is the explosive destruction of a star. Via a luminous outpouring of radiation, the SN can rival the brightness of its SN host galaxy for months or years. In the past decade, astronomical surveys regularly observing the sky to deep limiting magnitudes have revealed that core collapse SNe (the demises of massive stars) are sometimes preceded by eruptive episodes by the progenitor stars during the years before the eventual SN explosion. Such SNe tend to show strong signatures of interaction between the SN ejecta and the circumstellar medium (CSM) deposited by the star before the SN explosion, likely by mass-loss episodes like the ones we have started to observe regularly. The complex CSM resolved around certain giant stars in our own galaxy and the eruptions of giant stars like η Car in the 19th century can be seen in this context. As the SN ejecta of an interacting SN sweep up the CSM of the progenitor, radiation from this process offers observers opportunity to scan the late mass loss history of the progenitor. In this thesis, interacting SNe and eruptive mass loss of their progenitors is discussed. The SN iPTF13z (discovered by the intermediate Palomar Transient Factory, iPTF) is presented. This transient was followed with optical photometry and spectroscopy during 1000 days and displayed a light curve with several conspicuous re-brigthenings ("bumps"), likely arising from SN ejecta interacting with denser regions in the CSM. Around 200 days before discovery, in archival data we found a clear precursor outburst lasting >~ 50 days. A well-observed (but not necessarily well understood) event like SN 2009ip, which showed both precursor outbursts and a light curve bump, makes an interesting comparison object. The embedding of the (possible) SN in a CSM makes it hard to tell if a destructive SN explosion actually happened. In this respect, iPTF13z is compared to e.g. SN 2009ip but also to long-lived interacting SNe like SN 1988Z. Some suggestions for future investigations are offered, to tie light curve bumps to precursor events and to clarify the question of core collapse in the ambiguous cases of some interacting SNe.
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| 246. |
- Nyholm, Anders, 1985-
(författare)
-
Supernova surroundings on circumstellar and galactic scales
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Some stars cease to be in a bright and destructive display called a supernova. This thesis explores what we can learn about supernovae (SNe) by studying their immediate surroundings, and what the SNe can teach us about their environments. The work presented is mostly based on the rich harvest of observations from 2009-2017 by the Palomar Transient Factory (PTF) and its successor, the intermediate PTF (iPTF). The PTF/iPTF was an untargeted sky survey at Palomar Observatory, aimed at finding and following up astronomical transients, such as SNe. During its existence, a massive star typically loses several solar masses of material. If much mass is lost in the decades or centuries before the SN, this material around the star (the circumstellar medium, CSM) will be quickly swept up by the ejecta of the eventual SN. This interaction can contribute strongly to the luminosity of the SN and make the light curve of an interacting SN carry signs of the progenitor star mass loss history. SNe with a hydrogen-rich CSM are called SNe Type IIn. A SN of this type, iPTF13z, found and followed by iPTF, had a slowly declining lightcurve with at least 5 major rebrightenings ("bumps") indicating rich structure in the CSM. Archival images clearly shows a precursor outburst about 210 days before the SN discovery, demonstrating the iPTF13z progenitor to be restless before its demise. Type IIn supernovae are heterogeneous, but only limited statistics has been done on samples. From PTF/iPTF, a sample of 42 SNe Type IIn was therefore selected, with photometry allowing their light curve rise times, decline rates and peak luminosities to be measured. It was shown that more luminous events are generally more long-lasting, but no strong correlation was found between rise times and peak luminosities. Two clusters of risetimes (around 20 and 50 days, respectively) were identified. The less long-lasting SNe Type IIn dominate the sample, suggesting that stars with a less extended dense CSM might be more common among SN Type IIn progenitors. Thermonuclear SNe (SNe Type Ia) are useful as standardisable candles, but no secure identification has yet been made of the progenitor system of a SN Type Ia. Using a late-time spectrum from the Nordic Optical Telescope of the nearby thermonuclear SN 2014J, a search for material ablated from a possible non-compact companion gave the upper limit of about 0.0085 solar masses of hydrogen-rich ablated gas. One likely explanation is that the SN 2014J progenitor system was a binary white dwarf. Supernovae are also useful tracers of the star formation history in their host galaxies, with SNe Type Ia tracing earlier epochs of star formation and exploding massive stars tracing more recent. For active galactic nuclei (AGN, the luminous centres of galaxies harbouring accreting supermassive black holes) SNe allows the so-called unification model to be tested. The unification model assumes that the main distinction between the two types of AGN is the viewing angle towards the central black hole, and that other properties (e.g. star formation history) of the host galaxies should be the same for the two AGN types. Matching 2190 SNe from PTF/iPTF to about 89000 AGN with spectra from the Sloan Digital Sky Survey, a significantly higher number of SNe in the hosts of AGN type 2 was found, challenging the unification model.
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| 247. |
- Onori, F., et al.
(författare)
-
The nuclear transient AT 2017gge : a tidal disruption event in a dusty and gas-rich environment and the awakening of a dormant SMBH
- 2022
-
Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 517:1, s. 76-98
-
Tidskriftsartikel (refereegranskat)abstract
- We present the results from a dense multwavelength [optical/UV, near-infrared (IR), and X-ray] follow-up campaign of the nuclear transient AT 2017gge, covering a total of 1698 d from the transient's discovery. The bolometric light curve, the blackbody temperature and radius, the broad H and He i lambda 5876 emission lines and their evolution with time, are all consistent with a tidal disruption event (TDE) nature. A soft X-ray flare is detected with a delay of similar to 200 d with respect to the optical/UV peak and it is rapidly followed by the emergence of a broad He ii lambda 4686 and by a number of long-lasting high ionization coronal emission lines. This indicate a clear connection between a TDE flare and the appearance of extreme coronal line emission (ECLEs). An IR echo, resulting from dust re-radiation of the optical/UV TDE light is observed after the X-ray flare and the associated near-IR spectra show a transient broad feature in correspondence of the He i lambda 10830 and, for the first time in a TDE, a transient high-ionization coronal NIR line (the [Fe xiii] lambda 10798) is also detected. The data are well explained by a scenario in which a TDE occurs in a gas-and-dust rich environment and its optical/UV, soft X-ray, and IR emission have different origins and locations. The optical emission may be produced by stellar debris stream collisions prior to the accretion disc formation, which is instead responsible for the soft X-ray flare, emitted after the end of the circularization process.
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| 248. |
- Pastorello, A., et al.
(författare)
-
Forbidden hugs in pandemic times I. Luminous red nova AT 2019zhd, a new merger in M 31
- 2021
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 646
-
Tidskriftsartikel (refereegranskat)abstract
- We present the follow-up campaign of the luminous red nova (LRN) AT 2019zhd, the third event of this class observed in M 31. The object was followed by several sky surveys for about five months before the outburst, during which it showed a slow luminosity rise. In this phase, the absolute magnitude ranged from M-r=-2.8 +/- 0.2 mag to M-r=-5.6 +/- 0.1 mag. Then, over a four to five day period, AT 2019zhd experienced a major brightening, reaching a peak of M-r=-9.61 +/- 0.08 mag and an optical luminosity of 1.4x10(39) erg s(-1). After a fast decline, the light curve settled onto a short-duration plateau in the red bands. Although less pronounced, this feature is reminiscent of the second red maximum observed in other LRNe. This phase was followed by a rapid linear decline in all bands. At maximum, the spectra show a blue continuum with prominent Balmer emission lines. The post-maximum spectra show a much redder continuum, resembling that of an intermediate-type star. In this phase, H alpha becomes very weak, H beta is no longer detectable, and a forest of narrow absorption metal lines now dominate the spectrum. The latest spectra, obtained during the post-plateau decline, show a very red continuum (T-eff approximate to 3000 K) with broad molecular bands of TiO, similar to those of M-type stars. The long-lasting, slow photometric rise observed before the peak resembles that of LRN V1309 Sco, which was interpreted as the signature of the common-envelope ejection. The subsequent outburst is likely due to the gas outflow following a stellar merging event. The inspection of archival HST images taken 22 years before the LRN discovery reveals a faint red source (M-F555W=0.21 +/- 0.14 mag, with F555W-F814W=2.96 +/- 0.12 mag) at the position of AT 2019zhd, which is the most likely quiescent precursor. The source is consistent with expectations for a binary system including a predominant M5-type star.
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| 249. |
- Pastorello, A., et al.
(författare)
-
Forbidden hugs in pandemic times II. The luminous red nova variety AT 2020hat and AT 2020kog
- 2021
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 647
-
Tidskriftsartikel (refereegranskat)abstract
- We present the results of our monitoring campaigns of the luminous red novae (LRNe) AT 2020hat in NGC 5068 and AT 2020kog in NGC 6106. The two objects were imaged (and detected) before their discovery by routine survey operations. They show a general trend of slow luminosity rise, lasting at least a few months. The subsequent major LRN outbursts were extensively followed in photometry and spectroscopy. The light curves present an initial short-duration peak, followed by a redder plateau phase. AT 2020kog is a moderately luminous event peaking at similar to 7 x 10(40) erg s(-1), while AT 2020hat is almost one order of magnitude fainter than AT 2020kog, although it is still more luminous than V838 Mon. In analogy with other LRNe, the spectra of AT 2020kog change significantly with time. They resemble those of type TM supernovae at early phases, then they become similar to those of K-type stars during the plateau, and to M-type stars at very late phases. In contrast, AT 2020hat already shows a redder continuum at early epochs, and its spectrum shows the late appearance of molecular bands. A moderate-resolution spectrum of AT 2020hat taken at +37 d after maximum shows a forest of narrow P Cygni lines of metals with velocities of 180 km s(-1), along with an Ha emission with a full-width at half-maximum velocity of 250 km s(-1). For AT 2020hat, a robust constraint on its quiescent progenitor is provided by archival images of the Hubble Space Telescope. The progenitor is clearly detected as a mid-K type star, with an absolute magnitude of M-F606W = -3.33 +/- 0.09 mag and a colour of F606W - F814W = 1.14 +/- 0.05 mag, which are inconsistent with the expectations from a massive star that could later produce a core-collapse supernova. Although quite peculiar, the two objects nicely match the progenitor versus light curve absolute magnitude correlations discussed in the literature.
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| 250. |
- Pastorello, A., et al.
(författare)
-
Supernovae 2016bdu and 2005gl, and their link with SN 2009ip-like transients : another piece of the puzzle
- 2018
-
Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 474:1, s. 197-218
-
Tidskriftsartikel (refereegranskat)abstract
- Supernova (SN) 2016bdu is an unusual transient resembling SN 2009ip. SN 2009ip-like events are characterized by a long-lasting phase of erratic variability that ends with two luminous outbursts a few weeks apart. The second outburst is significantly more luminous (about 3 mag) than the first. In the case of SN 2016bdu, the first outburst (Event A) reached an absolute magnitude M-r approximate to -15.3 mag, while the second one (Event B) occurred over one month later and reached M-r approximate to -18 mag. By inspecting archival data, a faint source at the position of SN 2016bdu is several times in the past few years. We interpret these detections as signatures of a phase of erratic variability, similar to that experienced by SN 2009ip between 2008 and mid-2012, and resembling the currently observed variability of the luminous blue variable SN 2000ch in NGC 3432. Spectroscopic monitoring of SN 2016bdu during the second peak initially shows features typical of an SN IIn. One month after the Event B maximum, the spectra develop broad Balmer lines with P Cygni profiles and broad metal features. At these late phases, the spectra resemble those of a typical Type II SN. All members of this SN 2009ip-like group are remarkably similar to the Type IIn SN 2005gl. For this object, the claim of a terminal SN explosion is supported by the disappearance of the progenitor star. While the similarity with SN 2005gl supports a genuine SN explosion scenario for SN 2009ip-like events, the unequivocal detection of nucleosynthesized elements in their nebular spectra is still missing.
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