700 research outputs found
Measurements of the effect of horizontal variability of atmospheric backscatter on dial measurements
The horizontal variability of atmospheric backscatter may have a substantial effect on how Differential Absorption Lidar (DIAL) data must be taken and analyzed. To minimize errors, lidar pulse pairs are taken with time separations which are short compared to the time scales associated with variations in atmospheric backscatter. To assess the atmospheric variability for time scales which are long compared to the lidar pulse repetition rate, the variance of the lidar return signal in a given channel can be computed. The variances of the on-line, off-line, and ration of the on-line to off-line signals at given altitudes obtained with the dual solid-state Alexandrite laser system were calculated. These evaluations were made for both down-looking aircraft and up-looking ground-based lidar data. Data were taken with 200 microsecond separation between on-line and off-line laser pulses, 30 m altitude resolution, 5 Hz repetition rate, and the signal were normalized for outgoing laser energy
Homotheties and topology of tangent sphere bundles
We prove a Theorem on homotheties between two given tangent sphere bundles
of a Riemannian manifold of , assuming different
variable radius functions and weighted Sasaki metrics induced by the
conformal class of . New examples are shown of manifolds with constant
positive or with constant negative scalar curvature, which are not Einstein.
Recalling results on the associated almost complex structure and
symplectic structure on the manifold , generalizing the
well-known structure of Sasaki by admitting weights and connections with
torsion, we compute the Chern and the Stiefel-Whitney characteristic classes of
the manifolds and .Comment: 15 pages, to appear in Journal of Geometr
Systematic combination of Lean Management with digitalization to improve production systems on the example of Jidoka 4.0
© The Author(s) 2020. Lean Management builds the basis for efficient production systems for many industrial companies. However, lots of potentials of Lean Management have been lifted and information and communication technologies in the context of digitalization and cyber-physical production systems (CPPS) offer new possibilities to enhance the performance of companies. Even though surveys indicate that companies recognize these potentials, especially small and medium-sized companies still face challenges in selection and implementation of suitable solutions. Thus, the research project GaProSys 4.0 aims at supporting companies with a systematic approach to combine existing structures of Lean Management with potentials of digitalization in development of a new set of methods to enhance production systems. This paper presents the approach of the research project to develop a structured set of methods and provides an example to illustrate the potentials
The role of appetite-related hormones, adaptive thermogenesis, perceived hunger and stress in long-term weight-loss maintenance: a mixed-methods study
Background/objectives:
Weight-loss maintenance is challenging, and few succeed in the long term. This study aimed to explain how appetite-related hormones, adaptive thermogenesis, perceived hunger and stress influence weight-loss maintenance.
Subjects/methods:
Fifteen adult women (age, 46.3 ± 9.5 years; BMI, 39.4 ± 4.3 kg/m2) participated in a 24-month intervention, which included 3–5 months total diet replacement (825–853 kcal/d). Body weight and composition (Magnetic Resonance Imaging), resting metabolic rate (indirect calorimetry), and fasting plasma concentration of leptin, ghrelin, glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and growth differentiation factor 15 (GDF-15) were measured at baseline and after weight loss, around 6 months. Perceptions relating to weight-loss maintenance were explored using qualitative interviews.
Results:
Mean (SD) changes in body weight (−13.8 ± 6.3 kg) and total adipose tissue (−11.5 ± 4.9 kg) were significant (P < 0.001). Weight loss was associated with a significant reduction in resting metabolic rate (−291 ± 226 kcal/day, P < 0.001) and adaptive thermogenesis (−150 ± 162 kcal/day, P = 0.003), reduction in leptin (P < 0.001) and GLP-1 (P = 0.015), an increase in ghrelin (P < 0.001), and no changes in PYY and GDF-15. Weight regain between 6 and 24 months (6.1 ± 6.3 kg, P < 0.05) was correlated positively with change in GLP-1 (r = 0.5, P = 0.037) and negatively with GLP-1 at baseline (r = −0.7, P = 0.003) and after weight loss (r = −0.7, P = 0.005). Participants did not report increased hunger after weight loss, and stress-related/emotional eating was perceived as the main reason for regain.
Conclusions:
Weight regain is more likely with lower fasting GLP-1 and greater reduction in GLP-1 after weight loss, but psychological aspects of eating behaviour appear as important in attenuating weight-loss maintenance
Equilibrium of sinks and sources of sulphate over Europe: comparison between a six-year simulation and EMEP observations
Sulphate distributions were simulated with a global chemistry transport model. A chemical scheme describing the sulphur cycle and the parameterisations of the main sinks for sulphate aerosols were included in the model. A six-year simulation was conducted from the years 2000 to 2005, driven by the ECMWF operational analyses. Emissions come from an inventory representative of the year 2000. This paper focuses on the analysis of the sulphate sinks and sources over Europe for the entire period of simulation. The Sulphate burden shows a marked annual cycle, which is the result of the annual variations of the aqueous and gaseous chemistry. Regionally, the monthly mean aerosol burden can vary by a factor of 2 from one year to another, because of different weather conditions, driving chemistry, transport and wet deposition of sulphate aerosols. Sulphate ground concentrations, scavenging fluxes and precipitation modelled were compared with observations. The model represents quite well sulphate fields over Europe, but has a general tendency to overestimate sulphate ground concentrations, in particular over Northern Europe. We assume that it is linked to the representation of the scavenging fluxes, which are underestimated. We suggest that uncertainties in modelled precipitation explain only partially the underestimation of the scavenging fluxes in the model
From lean production to Industrie 4.0: More autonomy for employees?
The article examines the relationship between lean production and Industrie 4.0 focusing on the question of autonomy in the work process. In contrast to the claim made by official Industrie 4.0 concepts that the autonomy of the employees would increase, we see in the current implementation projects a tendency towards greater standardization and control of work. This is in continuity with concepts of lean production, but neglects the participation-oriented elements of lean production such as teamwork and shop-floor-based improvement activities. Our argument is developed by analyzing practical examples from three relevant fields (digital assistance systems, data-based process management, modular assembly). The conclusions of this article also discuss the extent to which the concept of individual autonomy is suitable for the assessment of Industrie 4.0 concepts, given the high levels of interdependence already achieved in production processes
Католицька концепція міжрелігійного діалогу: зміна акцентів
In Arabidopsis roots, the transcription factor MYB72 plays a dual role in the onset of rhizobacteria-induced systemic resistance (ISR) and plant survival under conditions of limited iron availability. Previously, it was shown that MYB72 coordinates the expression of a gene module that promotes synthesis and excretion of iron-mobilizing phenolic compounds in the rhizosphere, a process involved in both iron acquisition and ISR signaling. Here, we show that volatile compounds (VOCs) from ISR-inducing Pseudomonas bacteria are important elicitors of MYB72. VOCs-induced MYB72 is co-expressed with the iron uptake-related genes FERRIC REDUCTION OXIDASE 2 (FRO2) and IRON-REGULATED TRANSPORTER 1 (IRT1) in a FER-LIKE IRON DEFICIENCY INDUCED TRANSCRIPTION FACTOR (FIT)-dependent manner, indicating that MYB72 is an intrinsic part of the plants’ iron acquisition response that is typically activated upon iron starvation. However, VOCs-induced MYB72 is activated independently of the iron availability in the root vicinity. Moreover, rhizobacterial VOCs-mediated induction of MYB72 requires photosynthesis-related signals, while iron deficiency in the rhizosphere can activate MYB72 in the absence of shoot-derived signals. Together, these results show that the ISR- and iron acquisition-related transcription factor MYB72 in Arabidopsis roots is activated by rhizobacterial volatiles and photosynthesis-related signals, and can enhance the iron acquisition capacity of roots independently of the iron availability in the rhizosphere. This work highlights the role of MYB72 in plant processes by which root microbiota simultaneously stimulate systemic immunity and activate the iron uptake machinery in their host plants
Nonintegrability of the two-body problem in constant curvature spaces
We consider the reduced two-body problem with the Newton and the oscillator
potentials on the sphere and the hyperbolic plane .
For both types of interaction we prove the nonexistence of an additional
meromorphic integral for the complexified dynamic systems.Comment: 20 pages, typos correcte
Hydrodynamic Synchronisation of Model Microswimmers
We define a model microswimmer with a variable cycle time, thus allowing the
possibility of phase locking driven by hydrodynamic interactions between
swimmers. We find that, for extensile or contractile swimmers, phase locking
does occur, with the relative phase of the two swimmers being, in general,
close to 0 or pi, depending on their relative position and orientation. We show
that, as expected on grounds of symmetry, self T-dual swimmers, which are
time-reversal covariant, do not phase-lock. We also discuss the phase behaviour
of a line of tethered swimmers, or pumps. These show oscillations in their
relative phases reminiscent of the metachronal waves of cilia.Comment: 17 pages, 8 figure
‘I have been all in, I have been all out and I have been everything in-between’: a 2-year longitudinal qualitative study of weight-loss maintenance
Background:
Qualitative studies investigating weight management experiences are usually cross‐sectional or of short duration, which limits understanding of the long‐term challenges.
Methods:
Eleven women [mean (SD) age 44.9 (9.8) years; body mass index 40.3 (4.0) kg m−2] participated in this longitudinal qualitative study, which included up to 20 weeks of total diet replacement (825–853 kcal day−1) and ongoing support for weight loss maintenance (WLM), to 2 years. Semi‐structured interviews were conducted at baseline and programme end, as well as at key intervals during the intervention. Questions examined five theoretical themes: motivation, self‐regulation, habits, psychological resources and social/environmental influences. Data were coded and analysed in nvivo (https://qsrinternational.com/nvivo) using the framework method.
Results:
In total, 64 interviews were completed (median, n = 6 per participant). Mean (SD) weight loss was 15.7 (9.6) kg (14.6% body weight) at 6 months and 9.6 (9.9) kg (8.8% body weight) at 2 years. The prespecified theoretical model offered a useful framework to capture the variability of experiences. Negative aspects of obesity were strong motivations for weight loss and maintenance. Perceiving new routines as sustainable and developing a ‘maintenance mindset’ was characteristic of ‘Maintainers’, whereas meeting emotional needs at the expense of WLM goals during periods of stress and negative mood states was reported more often by ‘Regainers’. Optimistic beliefs about maintaining weight losses appeared to interfere with barrier identification and coping planning for most participants.
Conclusions:
People tended to be very optimistic about WLM without acknowledging barriers and this may undermine longer‐term outcomes. The potential for regain remained over time, mainly as a result of emotion‐triggered eating to alleviate stress and negative feelings. More active self‐regulation during these circumstances may improve WLM, and these situations represent important targets for intervention
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