Optical Lattice Trap for Kerr Solitons

We show theoretically and numerically that dichromatic pumping of a nonlinear microresonator by two continuous wave coherent optical pumps creates an optical lattice trap that results in the localization of intra-cavity Kerr solitons with soliton positions defined by the beat frequency of the pumps. This phenomenon corresponds to the stabilization of the Kerr frequency comb repetition rate. The locking of the second pump, through adiabatic tuning of its frequency, to the comb generated by the first pump allows transitioning to single-soliton states, manipulating the position of Kerr solitons in the cavity, and tuning the frequency comb repetition rate within the locking range. It also explains soliton crystal formation in resonators supporting a dispersive wave emitted as a result of higher-order group velocity dispersion or avoided mode crossing. We show that dichromatic pumping by externally stabilized pumps can be utilized for stabilization of microresonator-based optical frequency combs when the comb span does not cover an octave or a significant fraction thereof and standard self-referencing techniques cannot be employed. Our findings have significant ramifications for high-precision applications of optical frequency combs in spectrally pure signal generation, metrology, and timekeeping.Comment: 13 pages, 12 figure

The effect of 12 weeks Anethum graveolens (dill) on metabolic markers in patients with metabolic syndrome; A randomized double blind controlled trial

Background: The clustering of metabolic abnormalities defined as metabolic syndrome is now both a public health and a clinical problem .While interest in herbal medicine has greatly increased, lack of human evidence to support efficacies shown in animals does exist. This clinical trial study designed to investigate whether herbal medicine, Anethum graveolens (dill) extract, could improve metabolic components in patients with metabolic syndrome. Methods: A double-blind, randomized, placebo-controlled trial using a parallel design was conducted. 24 subjects who had metabolic syndrome diagnostic criteria (update of ATP III) were randomly assigned to either dill extract (n = 12) or placebo (n = 12) for 3 months. Results: Across lipid component of metabolic syndrome, no significant differences in triglyceride (TG) concentration and high density lipoprotein cholesterol were seen between the two groups. However TG improved significantly from baseline (257.0 vs. 201.5p = 0.01) with dill treatment but such a significant effect was not observed in placebo group. Moreover, no significant differences in waist circumference, blood pressure and fasting blood sugar were seen between two groups after 3 months follow up period. Conclusion: In this small clinical trial in patients with metabolic syndrome, 12 weeks of dill extract treatment had a beneficial effect in terms of reducing TG from baseline. However dill treatment was not associated with a significant improvement in metabolic syndrome related markers compared to control group. Larger studies might be required to prove the efficacy and safety of long-Term administration of dill to resolve metabolic syndrome components. © 2012 Mansouri et al.; licensee BioMed Central Ltd

Analysing the effect of lean on the performance of NPD projects using system dynamics modelling

To be able to survive in today’s fast-changing market environment companies are looking for innovative ways to improve the performance of their new product development (NPD) processes. However, uncertainty and rework are among characteristics of NPD which make them difficult to manage. Implementing lean in NPD is an innovative approach to address this issue. Using system dynamics approach to model set-based concurrent engineering as a fundamental element of lean product development, this paper shows the positive effect on of adopting this strategy on the time, cost and quality of NPD projects, in comparison with the traditional point-based design

The effect of Lean implementation on the efficiency and effectiveness of new product development processes

Although increasing the new product development speed and improving its cost effectiveness as well as enhancing the process quality have been at the centre of attention of many companies, there is still significant opposition to the 'better, faster and cheaper' paradigm. Improvement of new product development processes using Lean principles has been claimed to be an effective way to reach to this goal. In this conceptual paper, first the efficiency and effectiveness in new product development processes and the key components of Lean product development has been defined, then, an introduction to modelling the process based on System Dynamics, to develop the interrelationships between Lean components and performance measures, has been discussed

Interaction between genotype and climates for Holstein milk production traits in Iran

This study was designed to investigate the interaction between genotype and climate for milk and fat production traits of Iranian Holstein dairy herds. Milk and fat production data were grouped in 5 climates, on the basis of Extended De Martonne method. (Co)Variance components and genetic parameters of first lactation records from 514 herds were estimated by DFREML procedure. Estimation of genetic parameters by univariate animal model showed that heritability of milk and fat yields were from 0.22 to 0.30 and 0.06 to 0.26, respectively; that proved by the results of multivariate model. Genetic correlations between different climates ranged from 0.66 to 1 for milk yield and 0.16 to 1 for fat yield, respectively. Calculated genetic correlation between milk production traits in 5 various climates of Iran showed that there is a significant interaction between humid climate with other climates for both milk and fat yield traits. Using Spearman and Rank correlation for estimation of correlation between bulls breading values, for two traits showed the significant genotype by environment interaction between humid climate and Meditrranean climate for milk yield and between humid climate and other climates for fat yield.Key words: Holstein, genetic correlation, breeding value, genotype by environment interaction

Abusive supervision in commercial kitchens:Insights from the restaurant industry

This mixed-method study investigates how abusive supervision and bullying impact job satisfaction and turnover intentions among employees in an environment plagued by ingrained incivility: commercial kitchens. Underpinned by social learning theory, we draw from 832 survey responses and 20 in-depth interviews to explore the extent to which supervisory abuse and workplace bullying negatively impact employee perceptions of their working environment while also investigating positive alternatives therein (e.g., authentic leadership and encouragement of creativity). Results suggest that, despite day-to-day challenges posed by abusive leadership, a strong sense of camaraderie and passion for kitchen work stimulated a commitment to the job. Accordingly, the study concludes that the inherently creative nature of commercial kitchen work and the personalities of fellow staff played a significant role in retaining employees. It thus highlights the complexity of food service employee retention and suggests that a holistic understanding of both leadership dynamics and intrinsic motives is essential

All-Optical Dissipative Discrete Time Crystals

Time crystals are periodic states exhibiting spontaneous symmetry breaking in either time-independent or periodically forced quantum many-body systems. Spontaneous modification of discrete time translation symmetry in a periodically driven physical system can create a discrete time crystal (DTC). DTCs constitute a state of matter with properties such as temporal rigid long-range order and coherence which are inherently desirable for quantum computing and quantum information processing. Despite their appeal, experimental demonstrations of DTCs are scarce and hence many significant aspects of their behavior remain unexplored. Here, we report the experimental observation and theoretical investigation of photonic DTCs in a Kerr-nonlinear optical microcavity. Empowered by the simultaneous self-injection locking of two independent lasers with arbitrarily large frequency separation to two cavity modes and a dissipative soliton, this room-temperature all-optical platform enables observing novel states like DTCs carrying defects, and realizing long-awaited phenomena such as DTC phase transitions and mutual interactions. To the best of our knowledge, this is the first experimental demonstration of a dissipative DTC, as well as the concurrent self-injection locking of two continuous-wave lasers to different modes of the same family in a Kerr cavity. Combined with monolithic fabrication, it can result in chip-scale DTCs, paving the way for liberating time crystals from sophisticated laboratory setups and propelling them toward real-world applications

Electric-field-induced nematic-cholesteric transition and 3-D director structures in homeotropic cells

We study the phase diagram of director structures in cholesteric liquid crystals of negative dielectric anisotropy in homeotropic cells of thickness d which is smaller than the cholesteric pitch p. The basic control parameters are the frustration ratio d/p and the applied voltage U. Fluorescence Confocal Polarising Microscopy allows us to directly and unambiguously determine the 3-D director structures. The results are of importance for potential applications of the cholesteric structures, such as switchable gratings and eyewear with tunable transparency based.Comment: Will be published in Physical Review