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Over the past decades it has become manifest that jealousy and envy may be quite prevalent within organizations (see e.g. Dogan & Vecchio, 2001; Smith, Merlone, & Duffy, 2017). Although the term “jealousy” is often used as more or less synonymous to “envy,” from a theoretical point of view jealousy and envy are evoked by different stimuli. Workplace jealousy refers to the negative thoughts and emotions that result from the interference by a coworker within a valued relationship at work, and may, for instance, be evoked when someone feels that his or her superior pays attention to a new colleague at the expense of the attention paid to him or her. In essence, workplace jealousy is triadic in that it involves three individuals: the focal employee, the rival, and the valued target person. In contrast, workplace envy is defined essentially in dyadic terms, and refers to the negative thoughts and emotions that result from the perception that a coworker has obtained outcomes or has capacities that one strongly desires (Vecchio, 2000). As noted by Sterling and Labianca (2015) “Envy is at its most basic level the pain felt at another’s good fortune” (p. 297; see also Tai, Narayanan, & McAllister, 2012). According to Parrott and Smith (1993), envy is characterized more by feelings of inferiority, longing, and resentment, whereas jealousy is characterized more by fear of loss, distrust, anxiety, and anger.
The main objective of this secondary analysis was to describe the nutritional status of the Better Outcomes in Labour Difficulty (BOLD) project study population and determine possible associations between maternal nutritional status (as reflected by maternal BMI at the time of birth) and severe neonatal outcomes (SNO). We also analysed previous and index maternal pathologies to determine associations with neonatal outcomes. We used the classification designed by Atalah for maternal BMI and compared with the Hyperglycaemia and Adverse Pregnancy Outcome study one. To describe the nutritional status of this population, figures of distribution and test of normality related to weight and BMI were presented for the women and their babies. To explore the association between maternal BMI data and SNO, the χ2 test was performed. To identify a maternal characteristic or a group of characteristics that could predict SNO, we used Fisher’s exact test using previous maternal pathology collected in the BOLD project as well as that in the index pregnancy. In this study, BMI at the time of birth was not associated with neonatal near miss or death. We found that previous maternal obesity, diabetes and chronic hypertension were associated with SNO. Maternal pathology in the index pregnancy such as other obstetric haemorrhage, pre-eclampsia, anaemia and gestational diabetes was associated with SNO.
The theme for this chapter as formulated by the editors was: “Can evolutionary psychology be used to solve social problems?” For the sake of simplicity, I use here a broad definition of evolutionary psychology as the evolutionary approach to human behavior, including approaches that have often been set apart, such as human sociobiology and human behavioral ecology (Laland & Brown, 2011). Although the question of the applicability of evolutionary thinking has occupied me for years and although I have applied such thinking to a variety of social problems, including occupational burnout, jealousy, and depression, I found it a real challenge to write a chapter on this issue. In fact, as I will argue, my answer to this question is not unequivocally positive. Instead, I will argue that evolutionary psychology does not provide clear solutions to all kinds of social problems.
Stictococcus vayssierei is a major pest of root and tuber crops in central Africa. However, data on its ecology are lacking. Here we provide an updated estimate of its distribution with the aim of facilitating the sustainable control of its populations. Surveys conducted in nine countries encompassing 13 ecological regions around the Congo basin showed that African root and tuber scale was present in Cameroon, Central African Republic, Congo, Democratic Republic of Congo, Equatorial Guinea, Gabon and Uganda. It was not found on the sites surveyed in Chad and Nigeria. The pest occurred in the forest and the forest-savannah mosaic as well as in the savannah where it was never recorded before. However, prevalence was higher in the forest (43.1%) where cassava was the most infested crop, compared to the savannah (9.2%) where aroids (cocoyam and taro) were the most infested crops. In the forest habitat, the pest was prevalent in all but two ecological regions: the Congolian swamp forests and the Southern Congolian forest-savanna mosaic. In the savannah habitat, it was restricted to the moist savannah highlands and absent from dry savannahs. The scale was not observed below 277 m asl. Where present, the scale was frequently (87.1% of the sites) attended by the ant Anoplolepis tenella. High densities (>1000 scales per plant) were recorded along the Cameroon–Gabon border. Good regulatory measures within and between countries are required to control the exchange of plant materials and limit its spread. The study provides information for niche modeling and risk mapping.
Dry permafrost - ground with temperature always below 0°C and containing negligible ice - overlying ice-cemented ground has been reported in the Dry Valleys of Antarctica and on Mars. Here we report on a new site (79°49.213'S, 83°18.860'W, 718 m elevation) located on the side of Mount Dolence in Ellsworth Land, Antarctica. Year-round temperature and humidity measurements indicate that dry permafrost is present between depths of 13.5 and 49.0 cm - the location of ice-cemented ground. The mean annual frost point of the ice-cemented ground is -17.0 ± 0.2°C and the mean annual frost point of the atmosphere is -22.7 ± 1°C. The corresponding mean annual temperatures are -19.2°C and -20.3°C. Neither the temperature of the ice-cemented ground nor the air rise above freezing. Both the dry permafrost and the ice table may be habitable. In the dry soil at 3 cm depth there are 80 hours in the summer when temperature exceeds -5°C and water activity exceeds 0.8. At the ice table, temperature exceeds -10°C and water activity exceeds 0.8 for 35 hours in the year. The ice table and the dry permafrost above it would be considered a ‘Special Region’ on Mars. Further microbial investigation of this site is indicated.
A multitude of risk/protective factors for anxiety and obsessive-compulsive disorders have been proposed. We conducted an umbrella review to summarize the evidence of the associations between risk/protective factors and each of the following disorders: specific phobia, social anxiety disorder, generalized anxiety disorder, panic disorder, and obsessive-compulsive disorder, and to assess the strength of this evidence whilst controlling for several biases.
Publication databases were searched for systematic reviews and meta-analyses examining associations between potential risk/protective factors and each of the disorders investigated. The evidence of the association between each factor and disorder was graded into convincing, highly suggestive, suggestive, weak, or non-significant according to a standardized classification based on: number of cases (>1000), random-effects p-values, 95% prediction intervals, confidence interval of the largest study, heterogeneity between studies, study effects, and excess of significance.
Nineteen systematic reviews and meta-analyses were included, corresponding to 216 individual studies covering 427 potential risk/protective factors. Only one factor association (early physical trauma as a risk factor for social anxiety disorder, OR 2.59, 95% CI 2.17–3.1) met all the criteria for convincing evidence. When excluding the requirement for more than 1000 cases, five factor associations met the other criteria for convincing evidence and 22 met the remaining criteria for highly suggestive evidence.
Although the amount and quality of the evidence for most risk/protective factors for anxiety and obsessive-compulsive disorders is limited, a number of factors significantly increase the risk for these disorders, may have potential prognostic ability and inform prevention.
Thanks especially to the ALMA interferometer, there are several new detections of CO gas in debris disks. Based on our own and archival ALMA observations, we found that the presence of CO gas in dust-rich debris disks around young (10–50 Myr) A-type stars is common. Interestingly, similarly dust-rich debris disks around young F-K type stars exhibit significantly lower gas incidence. The main difference between the two subsamples is related to a special population of gaseous debris disks whose total CO gas quantity is comparable to that of the less massive Herbig Ae disks. The origin of gas in these CO-rich debris systems is not fully clarified yet.
While the Sun is nowadays a quiet and well-balanced star, in its first few million years it might have been often out of temper, like those young low-mass stars which episodically undergo unpredictable outbursts. The prototype of one of the two classes of young erupting stars, EX Lupi, had its historically largest outburst in 2008. It brightened by a factor of 30 for six months, due to elevated accretion from the circumstellar disk on to the star. Our group observed the system during the outburst, and discovered the crystallisation of amorphous silicate grains in the inner disk by the heat of the outburst. Our mid-infrared monitoring of the freshly produced crystals revealed that their emission in the inner disk quickly dropped already within a year after the outburst. Here we report on new observations of the 10 µm silicate feature, obtained with the MIDI and VISIR instruments at Paranal Observatory, which demonstrate that within five years practically all forsterite disappeared from the inner disk. We attempt to model this process by an expanding wind that transports the crystals from the terrestrial zone to outer disk regions where comets are supposed to form. Since the eruptions of EX Lup are recurrent, we speculate that the early Sun also experienced similar brightenings, and the forming planetary system might have incorporated some of the mineralogical and chemical yields provided by the outbursts. EX Lup, as a proxy for the proto-Sun, may be a telltale object to understand the origin of molecules and minerals we routinely encounter on Earth.
Our aim is to present a new and so far most complete catalog of optically selected young stars. The basis of this work is an extensive literature search for young stars in all the known nearby (< 2 kpc) star forming regions, included in the Handbook of Star Forming Regions [4, 5], and in 67 additional catalogs. We collected data on known young, pre-main-sequence stars detected in optical bands. The catalog contains the celestial coordinates, object names, names of the enclosing star forming region, identification methods, distances, and other information (e.g., references, binarity) for 15208 young stellar objects. It is already in use by the Gaia Photometric Science Alerts Team to identify variable young stars in the Gaia data. Our catalog was cross-correlated with the Gaia DR2 and we obtained flux and distance estimations for 86% of the stars.
The earliest phases of star formation are characterised by intense mass accretion from the circumstellar disk to the central star. One group of young stellar objects, the FU Orionis-type stars exhibit accretion rate peaks accompanied by bright eruptions. The occurance of these outbursts might solve the luminosity problem of protostars, play a key role in accumulating the final star mass, and have a significant effect on the parameters of the envelope and the disk. In the framework of the Structured Accretion Disks ERC project, we are conducting a systematic investigation of these sources with millimeter interferometry to examine whether they represent normal young stars in exceptional times or they are unusual objects. Our results show that FU Orionis-type stars can be similar to both Class I and Class II systems and may be in a special evolutionary phase between the two classes with their infall-driven episodic eruptions being the main driving force of the transition.
We conducted global hydrodynamic simulations of protoplanetary disk evolution with an adaptive Shakura-Sunyaev α prescription to represent the layered disk structure, and starting with the collapse phase of the molecular cloud. With the canonical values of model parameters, self-consistent dead zones formed at the scale of a few au. The instabilities associated with the dead zone and corresponding outbursts, similar to FUor eruptions, were also observed in the simulations.
The origin of optical-infrared variability in young, intermediate mass Herbig Ae/Be stars is linked to their circumstellar disk. Therefore, variability could serve as a diagnostic tool to constrain the structure and dynamics of the (inner) disk. Here we discuss this diagnostic potential, and report some preliminary results from our coordinated BV RIJHKs and Spitzer monitoring observations of nine Herbig Ae stars. We aim to understand the response of the inner disks thermal emission on the changing stellar irradiation, and to separate it from UX Orionis-type fading events, which also provide information on the disk. This project is a pilot study for the era of time domain astronomy of young stars, opened by Kepler K2, Gaia, ASAS-SN, TESS, Spitzer, WISE, and JWST.
While the Sun is a quiet and well-balanced star now, during its first few million years it possessed a strong magnetic field and actively accreted material from its circumstellar environment. Theoretical models predict that under certain circumstances the interaction of a strongly magnetic star and its circumstellar disk may lead to short bursts of increased accretion onto the star (D’Angelo & Spruit 2012). Examples for this phenomenon may be the members of a group of young eruptive stars called EXors. Their prototype, EX Lup, had its historically largest outburst in 2008. Spectroscopic evidence suggests that the mass accretion proceeds through the same magnetospheric accretion channels both in quiescence and in outburst but with different mass flux (Sicilia-Aguilar et al. 2012). To characterize for the first time EX Lup’s magnetic field, we obtained spectropolarimetric monitoring for it with the CFHT/ESPaDOnS. We detected strong, poloidal magnetic field with a prominent cool polar cap and an accretion spot above it. We compared our results with numerical simulations, in order to check the applicability of the d’Angelo & Spruit model as an explanation of EX Lup’s accretion outbursts. If EX Lup is a good proxy for the proto-Sun, similar magnetic field-disk interactions and outbursts might have happened during the early evolution of the Solar System as well.
DQ Tau is a young low-mass spectroscopic binary, consisting of two almost equal-mass stars on a 15.8 day period surrounded by a circumbinary disk. We analyzed DQ Tau’s light curves obtained by Kepler K2, the Spitzer Space Telescope, and ground-based facilities. We observed variability phenomena, including rotational modulation by stellar spots, energetic stellar flares, brightening events around periastron due to increased accretion, and short dips due to temporary circumstellar obscuration. The study on DQ Tau will help in discovering and understanding the formation and evolution of other real-world examples of “Tatooine-like” systems. This is especially important because more and more evidence points to the possibility that all Sun-like stars were born in binary or multiple systems that broke up later due to dynamical interactions.
The early evolution of Sun-like stars may be interspersed by energetic FU Orionis (FUor) type accretion outbursts. We analysed eight years of photometric and spectroscopic variability of V582 Aur, a bona fide FUor, in outburst. While the accretion rate derived from near-infrared measurements was constant, radical brightness changes occurred due to dust clumps crossing the line of sight. The brightness minima resemble the variability patterns of the UXor phenomenon. Orbiting density enhancements or short-lived clumps moving in and out of the line-of-sight may explain these observations. Our message is that during FUor outbursts the inner disk is a dynamically active place, affecting the initial conditions for planet formation.
Having disk-to-star accretion rates on the order of 10-4M⊙/yr, FU Orionis-type stars (FUors) are thought to be the visible examples for episodic accretion. FUors are often surrounded by massive envelopes, which replenish the disk material and enable the disk to produce accretion outbursts. We observed the FUor-type star V346 Nor with ALMA at 1.3 mm continuum and in different CO rotational lines. We mapped the density and velocity structure of its envelope and analyzed the results using channel maps, position-velocity diagrams, and spectro-astrometric methods. We discovered a pseudo-disk and a Keplerian disk around a 0.1 M⊙ central star. We determined an infall rate from the envelope onto the disk of 6×10-6M⊙/yr, a factor of few higher than the quiescent accretion rate from the disk onto the star. This hints for a mismatch between the infall and accretion rates as the cause of the eruption.
Young stellar objects often show photometric variability, which is well examined at optical wavelengths, but more and more infrared data are also available. The wavelength dependence of the variability carries information on the physical cause of the changing brightness. Here, we examine seven T Tauri-type stars known for their large amplitude variability selected from the Campaign 13 field of the Kepler K2 mission. We complemented the K2 light curves by multifilter optical monitoring observations made with the 90 cm Schmidt telescope of Konkoly Observatory, and by 3.6 and 4.5 μm infrared photometry with a 20 hours cadence using the Spitzer Space Telescope. We found that the wavelength dependence of the observed variability is not consistent with changing interstellar extinction. We suggest that the brightness changes are due to variable accretion, causing a variable illumination of the inner disk.