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Well at Work: A Leader’s Positive Psychology Guide to Managing Stress and Manifesting Well-Being
Get PDFThrough this paper, I explore the current U.S. landscape of stress and work-related stress, including when it can be bad for us (i.e., distress and burnout) and good for us (i.e., eustress). Then, I draw on positive psychology - the science of well-being - and affiliated disciplines (e.g., positive organizational scholarship and positive organizational behavior) to offer science-based strategies for leaders to rethink and help manage stress and manifest well-being in the workplace. Specifically, I discuss meaning, mattering, and belonging as three interconnected and important principles for leaders to know and to put into practice through zones of control, low-cost, high- impact positive psychology interventions, such as job crafting, building self-efficacy and resilience, and creating high-quality connections. While this paper is certainly not the solution to work-related stress, it is a step and a tool for leaders towards more managed stress and manifested well-being in our workplaces
Module 14: Islamophobia in (non-US) Global Contexts
Get PDFhttps://repository.upenn.edu/teachingbeyondsept11-democracy-rights/1003/thumbnail.jp
The Effect of Jungle Light Spectrum on the Fearfulness of Commercial Broiler Chickens
No full textThere is more interest in how food animals are raised. One of the topics of most interest is how commercial broiler houses are lit. There is discussion about high intensity light (50 lux), natural light from windows compared to conventional dim lighting programs (2 – 5 lux) using “white” LED light. Chickens are prey animals that depend on their vision safety. Chickens “see” the word differently than humans and other animals in several significant ways. They have four cones for color vision compared to three for humans. This results in a broader light spectrum range especially in the lower wavelengths. They have very large eyes that when weighted together, weigh more than their brain. They have both binocular and monocular vision and can process two distinct images at the same time. This allows them to see what they are eating and watch for prey at the same time.
When designing a lighting program for chickens, these factors must be kept in perspective, so a light environment provides a feeling of safety and provides a spectrum that utilizes their full range. Recreating the lighting that chickens would experience in the wild may provide an environment where they are less fearful. The purpose of this trial was to compare production parameters and determine fearfulness of commercial broilers raised under white LED light of ~3500K and a light spectrum that simulates light in the jungle canopy. Four commercial broiler houses were utilized for the trial each with 19,200 birds. The source flocks were equally distributed within and between the houses. Birds were tested for fearfulness using several behavioral tests at 34 to 36 days of age. Birds were marketed at 54 days of age where performance and Key Welfare Indicators were assessed.
Live production parameters nor H:L ratio were influenced by the light spectrum but the results of the inversion test, isolation test and tonic immobility indicated birds raised under a jungle light spectrum were less fearful than birds raised under LED light
Hearing Hebrew Pharyngeals: Experimental evidence for a covert phonemic distinction
Get PDFWe report a lexical decision task experiment, in which words were manipulated such that two different sounds had been switched with each other: the voiceless pharyngeal and uvular fricatives. The former is a marked sound of some dialects of Modern Hebrew, the latter is a merged category corresponding to both the historical pharyngeal and the uvular in the production of most speakers. The two categories are represented by different letters in the orthographic system and each is associated with unique phonological processes. Socially, the pharyngeal is stereotyped; merging the categories is both more common and more prestigious in most social contexts. Speakers of Modern Hebrew with varied linguistic backgrounds, including Merged speakers who have not been exposed to non-merged dialects during most of their lives, are very good at acoustically distinguishing between these sounds (only slightly underperforming compared with Non-merged speakers). Nevertheless, we found that manipulated stimuli - which were not part of the input for language learners of either dialect - provoke different acceptance rates and reaction times, depending on the listener\u27s home dialect, in certain cases regardless of their production grammar. In particular, Non-merged speakers and Merged speakers who are 2nd generation listeners to non-merged dialects rejected switched category items at much higher rates and took longer to process them compared with Merged speakers who did not have early experience with the categorical distinction. We discuss these findings in the context of models of phonological representation and auditory word recognition
First-Principles Investigations On Raman Spectroscopy And Bulk Photovoltaic Effect
No full textLight-matter interaction, as the name suggested, describes the interaction between the illuminating light and different states of matters. In solid-state physics, people usually focus on how light influences the energetics and dynamics of materials where light is taken as a classical electromagnetic field. In the first part of this dissertation, we will focus on the situation where the frequency of light is lower than the band gaps of materials, so that the light will not be absorbed but scattered and possibly acquire a frequency shift, which is called Raman scattering. We will show how the conventional theory of Raman scattering developed for harmonic systems can be modified to treat highly anharmonic systems. The adapted theory will be used to reproduce the experimental Raman spectra of methylammonium lead iodide-a promising material for solar energy conversion-and demonstrate the atomistic origin of its strong lattice anharmonicity. Then, in the second part of this dissertation, we will shift our attention to the scenario where the photon energy surpasses the band gap and will be absorbed by the material. We will be mainly concerned with one specific phenomenon, the bulk photovoltaic effect (BPVE), which means that a steady DC current can be generated in spatially homogeneous but inversion-broken or time-reversal-broken materials. We will develop a theory for ballistic current, an important mechanism for BPVE in addition to shift current, and then use first-principles methods to evaluate it for real materials such as BaTiO3 and MoS2. Our theory and computation show clearly that the phonon ballistic current can be as important as shift current, while the exciton ballistic current is less appreciable. Moreover, we will investigate how BPVE will behave under a uniform magnetic field, demonstrating a sizable response of shift current at weak field and a nontrivial evolution of the spectral shape going into the strong field
Characterizing Ultrafast Equilibrium Dynamics Using Third-Order Nonlinear Mid-Infrared Spectroscopies
No full textCharacterizing equilibrium dynamics provides new insight into examining structure-function relationship in chemical reactions and understanding physical properties and processes in various systems. Third-order nonlinear mid-infrared spectroscopic techniques are powerful tools for investigating ultrafast dynamics under thermal equilibrium. In this thesis, vibrational energy relaxation and orientational relaxation dynamics were extracted from polarization-dependent pump probe spectroscopy and local environment dynamics surrounding a vibrational probe were detected using two-dimensional infrared spectroscopy.Effects of ligand structural variation on the ultrafast dynamics of a series of copper complexes were investigated. An azide group was attached to model copper complexes to serve as a vibrational probe. It was found that the peripheral phosphinimine ligands of the copper complex confined the orientational motion of azide and the degree of spatial restriction was quantified using the wobbling-in-a-cone model. The addition of phenyl groups in the ligands acted to create more accessible local environmental configurations for the azide group. The binding configuration and intramolecular motion of the vibrational probe can affect the dynamics detected. The dynamics detected by the azide group bound to the copper complexes were compared to those detected by an isothiocyanate group with a different binding angle. Molecular dynamics simulations showed that intramolecular reorientation of azide sampled a larger space leading to faster orientational relaxation compared to isothiocyanate. The local environment dynamics detected by azide were slower than those detected by isothiocyanate due to the change of local environment dynamics induced by the binding of different vibrational probes and the differences in the local environment dynamics detected along different spatial orientations. The ultrafast dynamics of liquid crystal systems were also investigated. The effects of gold nanoparticles and their capping ligands on the dynamics of 4-cyano-4′-pentylbiphenyl (5CB) during the isotropic-to-nematic phase transition were examined. Our preliminary results showed that the addition of impurities accelerated the dynamics of 5CB, and this acceleration effect was more significant for the ligands than the ligand-capped nanoparticles
Estimation And Inference For Convex Functions And Computational Efficiency In High Dimensional Statistics
Get PDFOptimization and statistics are intrinsically intertwined with each other. Optimization has been the ends of some statistical problems, like estimation and inference for the minimizer and the minimum of convex functions, and the means for other statistical problems, like computational concerns in high dimensional statistics. In this dissertation, we consider both optimization-related problems.Estimation and inference for the minimizer and minimum of convex functions have been longstanding problems with wide application in economics and health care. But existing approaches are insufficient due to their asymptotic nature and/or incapability of characterizing function-specific difficulty. We investigate the problems under non-asymptotic frameworks that characterize function-specific difficulty and propose adaptive computational-efficient optimal methods. The first two parts of the dissertation address these problems, briefly summarized as follows. • The first part focuses on univariate convex functions. We develop computationally efficient adaptive optimal procedures under local minimax framework and discover a novel Uncertainty Principle that provides a fundamental limit on how well the minimizer and minimum can be estimated simultaneously for any convex regression function. • The second part focuses on multivariate additive convex functions. Under function-specific benchmarks, we propose computationally efficient optimal methods and establish their optimality.
Computational efficiency is another optimization-related problem of increasingly importance in statistics, especially in the AI age where the scale of data is big and the requirement on computational time is high. To achieve the balance between running time and statistical accuracy, we propose a framework that provides theoretically guaranteed optimization methods together with the analysis of interplay between running time and statistical accuracy for a class of high-dimensional problems in the third part of the dissertation. Our framework consists of three parts, statistical-optimization interplay analysis, which characterizes optimization induced statistical error in a more essential way, optimization template algorithm, and optimization convergence analysis. We showcase the power of our framework through three example problems, where we get novel results for the first two and show that our framework adapts to the degenerate case through the third example
Characterizing Medial Temporal Lobe Neurodegeneration Due To Tau Pathology In Alzheimer\u27s Disease Using Postmortem Imaging
No full textTau neurofibrillary tangle (NFT) pathology in the medial temporal lobe (MTL) is closely linked to neurodegeneration, and is the early pathological change associated with Alzheimer’s Disease (AD). Using in vivo structural magnetic resonance image (MRI) analysis, volumetric change in the MTL caused by neurodegeneration can be measured. While these measurements have been shown to be sensitive to structural change during the early stages of AD, the potential of these measures as imaging biomarkers for early AD is limited by the fact that other neurodegenerative pathologies also affect MTL morphometry. Studies have suggested that different subregions of the MTL are differentially affected by AD and non-AD pathologies. Therefore, by characterizing MTL neurodegeneration due to the different pathologies, patterns of structural change specific to NFT pathology can be isolated. In this work, we hypothesize that MRI measurements obtained from MTL regions where structural change correlates most strongly with AD-specific pathology would result in biomarkers that are more sensitive to longitudinal change in the presence of preclinical AD.
To elucidate patterns of structural change in the MTL specifically associated with NFT pathology, the work presented in this dissertation leverages a postmortem imaging dataset which combines ultra-high resolution ex vivo MRI with ground truth information from serial histology, thus providing a direct link between structural changes in the MTL and the underlying pathology. Using ex vivo MRI and pathology datasets from a large number of MTL autopsy specimens, this dissertation focuses on the development and validation of computational image analysis techniques for groupwise analysis of the MTL. This work leverages advanced computational anatomy techniques and prior knowledge of cortical geometry to overcome challenges due to the complex and highly variable geometry of the hippocampus and MTL cortex. First, I present novel semi-automated and automated segmentation techniques that facilitate labeling of the MTL cortex and the stratum radiatum lacunosum moleculare (SRLM) layer of the hippocampus in high-resolution ex vivo MRI datasets. Segmentations of these structures are used to guide the alignment of the MTL across different specimens. Groupwise analysis relies on the creation of a normalized reference space across specimens via groupwise image registration. To this end, I explore two approaches for groupwise registration: 1) a volumetric approach which builds on a previously developed shape and intensity-based framework to construct a 3D probabilistic atlas of the MTL, and 2) a surface-based approach which provides implicit registration between specimens by applying a topological unfolding framework to the MTL.
As part of this work, we present a first-of-its-kind 3D computational atlas of the MTL, with anatomical subregion labels derived from serial histology on the basis of cytoarchitecture. Leveraging the developed registration frameworks and serial histology datasets, I investigate the relationship between tau pathology and regional MTL cortical thickness, while correcting for age and the presence of co-pathologies, and identify regional patterns of cortical thinning consistent with early histological studies. These analyses are performed using semi-quantitative ratings of neuropathology and quantitative 3D maps of tau NFT burden, and provide a more refined understanding of how tau pathology is associated with neurodegeneration in the MTL
Culturing Evolution: A History And Anthropology Of A Cognitive Science Of Culture In Illiberal Hungary
No full textSince the mid-twentieth century, an array of life, mind, and behavioral scientists have centered the concept of culture in novel research programs, attempting to investigate the old epistemic object with new scientific techniques. This dissertation asks how culture—long renowned for its imponderability and as something that one could only hope to understand or interpret through sustained periods of embodied immersion “in the field”—has in recent decades been transformed into an object for experimental knowledge production in mind and life science labs. Culturing Evolution traces the late twentieth century history of a new field of research called “Cultural Evolution,” which emerged and took shape at the interface of population genetics and cognitive science in the 1970s and 1980s. Based on fourteen months of fieldwork that I conducted in the Department of Cognitive Science at the Central European University in Budapest between 2019-2020, where one of the most prominent European research groups in the field of Cultural Evolution is based, I supplement this historical account of postwar life and mind sciences with ethnographic descriptions of the human practices, material sites, and technical instruments through which contemporary mind and life scientists conceptualize and materialize culture in terms of evolutionary and cognitive mechanisms. Finally, this study of new sciences of culture in twenty-first century Europe is also a study of an emerging politics of culture that is avowedly opposed to the liberal universalism of evolutionary and cognitive sciences. Weaving historical and anthropological forms of analysis, Culturing Evolution studies the simultaneous and conflicting efforts of liberal laboratory scientists and illiberal political actors to define culture and organize polities. By examining this linked set of sciences and politics of culture in Central Europe, this dissertation also illuminates certain contemporary relations between culture, science, liberalism, and the state
Clays, Ceramic Production, And Landscape At Archaic And Classical Eleon
No full textThis dissertation explores the production and use of Boeotian Kylix Ware during the Archaic period at the site of Eleon in Eastern Boeotia. Boeotian Kylix Ware (BKW) is a class of pottery particular to this region of central Greece, and was produced and used from the end of the seventh century BCE into the fifth century. BKW is found exclusively in burials and, at Eleon, in contexts related to a sanctuary on the acropolis. The 6th century BCE in Eastern Boeotia saw an increase in regional community cohesion and cooperation between settlements. Eleon’s role in the changing social, religious, and political landscape during this period, however, is unknown. This investigation uses material culture as evidence to examine changes in Boeotia during the Archaic period, and contributes to the understanding of Eleon as a local cult site during this time.Since BKW was produced and used in a limited geographical area, and used in specific ritual contexts, it offers a window into the social relationships and identity of its creators and users. Previous scholarship suggests that BKW was produced in a few centers in Eastern Boeotia. This dissertation focuses on 95 samples of BKW from Eleon to investigate the organization of production and to infer relationships between producers and users of the pottery at Eleon and in the region. Macroscopic and petrographic analysis of Eleon’s BKW, alongside geological prospection and petrographic analysis of sediments in Eastern Boeotia, provide insight into the production process. I suggest that multiple production units were active at Eleon during this period, and I argue that even as BKW production intensified at the end of the 6th century, production was decentralized. I also suggest that BKW production was closely tied to the production of other ceramic objects deposited at Eleon’s sanctuary, particularly figurines, roof tiles, and miniature pottery. This bottom-up approach to production of BKW is an important step in understanding interactions between individuals and groups at Eleon and across Eastern Boeotia