bluuebunny/crossref_metadata_2025 huggingface dataset:
Discrimination and the Returns to Cultural Assimilation in the Age of Mass Migration
Authors: Abramitzky Ran , Boustan Leah , Eriksson Katherine , Hao Stephanie
Published: May 2020

We document that, in the early twentieth century, children of immigrants who were given more-foreign first names completed fewer years of schooling, earned less, and married less assimilated spouses. However, we find few differences in the adult outcomes of brothers with more/less foreign-sounding first names. This pattern suggests that the negative association between ethnic names and adult outcomes in this era does not stem from discrimination on the basis of first names but instead reflects household differences associated with cultural assimilation. We cannot rule out discrimination on the basis of other ethnic cues.
Knowledge, Stories, and Culture in Organizations
Authors: Gibbons Robert , Prusak Laurence
Published: May 2020

Organizations are full of stories; organizational economics, not so much. Rather, organizational economics has little work that conceptualizes the role or measures the incidence of stories in organizations. This shortage concerns us not only because stories are prevalent in organizations but more importantly because we think some stories play a role in organizations that sheds light on why organizations exist and how they might be improved. In brief, we explore the idea that stories in organizations may induce a particular kind of organizational knowledge, of which organizational culture is a leading example.
Individual Identity and Organizational Identification: Evidence from a Field Experiment
Authors: Guadalupe Maria , Kinias Zoe , Schloderer Florian
Published: May 2020

This paper explores the relationship between individual identity and organizational attachment. Using individual data from employees at a large employer in the services sector, we show that making individual values salient (through a value affirmation) on average reduces organizational attachment. However, this effect is heterogenous across individuals: those initially attached to the organization increase their attachment, while those who started off less identified with the organization reduce their attachment. Overall, the results illustrate the importance of heterogeneity and how individual identity/values and organizational attachment can conflict.
Private Supply of Safe Assets: Shadow Banks Versus Traditional Banks
Authors: Gissler Stefan , Macchiavelli Marco , Narajabad Borghan
Published: May 2020

We show that the creation of private safe assets by shadow banks can decrease traditional banks' supply of safe assets. The 2014-2016 money fund reform created a large demand shock for safe assets, to which Federal Home Loan Banks (FHLBs) responded, expanding their balance sheets and increasing their issuance of short-term debt. To reduce the resulting interest rate risk, FHLBs shortened the repricing of their loans to banks. Focusing on small banks for which the reform was exogenous, we use a novel instrumental variable strategy to show that shadow banks create safe assets at the expense of banks' deposits.
The Demographic Effects of Dodging the Vietnam Draft
Authors: Bailey Martha J. , Chyn Eric
Published: May 2020

This paper quantifies the impact of the Vietnam War on fertility rates in the late 1960s and early 1970s. For draft-eligible men wishing to avoid military service, the hardship deferment (III-A) for paternity created a powerful incentive to father a child. We provide a time series suggesting that the risk of being drafted and the availability of the paternity deferments significantly increased US fertility rates, especially among childless women likely to be partnered with draft-eligible men. Our results suggest caution in attributing the decline in fertility after 1970 solely to the legalization of abortion.
The Impact of Parental Wealth on College Degree Attainment: Evidence from the Housing Boom and Bust
Authors: Johnson Rucker C.
Published: May 2020

This study provides new evidence on the impact of parental wealth on college degree attainment. Using geocoded data from the Panel Study of Income Dynamics (1968-2017) linked to local housing price data from the Federal Housing Finance Agency, the empirical strategy analyzes parental housing wealth changes induced by local housing booms of the late 1990s-early 2000s and the subsequent housing bust of the 2007-2009 period. 2SLS/IV estimates show parental wealth significantly increases the likelihood of earning a four-year college degree. Moreover, the combined effects of parental income and wealth are significantly greater than the effects of income alone.
Queens of the Desert: Convictism and Marital Attitudes across Australia
Authors: Baranov Victoria , De Haas Ralph , Grosjean Pauline
Published: May 2020

We merge data on spatial variation in the presence of convicts across eighteenth and nineteenth century Australia with results from the country's 2017 poll on same-sex marriage and with household survey data. These combined data allow us to identify the lasting impact of convict colonization on social norms about marriage. We find that in areas with higher historical convict concentrations, more Australians recently voted in favor of same-sex marriage and hold liberal views about marriage more generally. Our results highlight how founder populations can have lasting effects on locally held social norms.
Employment and Earnings for Federal Government Economists: Empirical Evidence by Gender and Race
Authors: Foster Lucia , Manzella Julia , McEntarfer Erika , Sandler Danielle H.
Published: May 2020

We contribute to the literature on diversity in the economics profession, which has mostly focused on academia, by providing a first look at the employment and earnings of federal government economists by gender and race. Combining micro-level data on federal workers with information on their earnings in federal and private sector jobs, we examine the share of federal government economists by race and gender, earnings differences by race and gender, and whether earning gaps differ during their federal government tenure.
Endocytosis and the internalization of pathogenic organisms: focus on phosphoinositides
Authors: Walpole Glenn F. W. , Grinstein Sergio
Published: May 2020

Despite their comparatively low abundance in biological membranes, phosphoinositides are key to the regulation of a diverse array of signaling pathways and direct membrane traffic. The role of phosphoinositides in the initiation and progression of endocytic pathways has been studied in considerable depth. Recent advances have revealed that distinct phosphoinositide species feature prominently in clathrin-dependent and -independent endocytosis as well as in phagocytosis and macropinocytosis. Moreover, a variety of intracellular and cell-associated pathogens have developed strategies to commandeer host cell phosphoinositide metabolism to gain entry and/or metabolic advantage, thereby promoting their survival and proliferation. Here, we briefly survey the current knowledge on the involvement of phosphoinositides in endocytosis, phagocytosis, and macropinocytosis and highlight several examples of molecular mimicry employed by pathogens to either “hitch a ride” on endocytic pathways endogenous to the host or create an entry path of their own.
THE POSSIBILITY OF USING ALTERNATIVE INTANGIBLE RESOURCES TO MOTIVATE STAFF IN THE CONDITIONS RESOURCE CONSTRAINTS
Authors: Byelozyerova Y. , Lebedeva Yu.
Published: May 2020

The manager is always in search of unique methods to stimulate his staff. For each employee, the set of these tools will be unique. Most organizations are highly competitive and have limited financial resources. In these conditions, it is increasingly difficult to use the fastest way to stimulate – money. Exchange in all spheres of life should be strictly equivalent. You need to be able to pay with alternative resources. These resources should be perceived by the employee as a value. It is proposed to use the elements of a harmonized model of personality development to build an effective system of non-material motivation. The aim of the authors is to show the intangible tools that allow to achieve staff loyalty and productivity growth with minimal financial investments.
DEVELOPMENT OF ICT COMPETENCIES OF A YOUNG SPECIALIST IN THE FIELD OF RISK ANALYSIS AND ECONOMIC SECURITY IN THE CURRENT CHALLENGES OF THE LABOR MARKET
Authors: Konovalova O. , Volkonskiy V.
Published: May 2020

The article analyzes the current trends in the field of transformation of professional competencies being formed by educational institutions of higher education among specialists in the field of economic security and risk analysis. Actual requirements of employers in the labor market in the field of economics are described. The main reasons for the need to change the list and composition of professional competencies are identified. On the example of the current Russian educational standard, the shortcomings of the existing regulatory framework are identified. Scenarios of the development of the educational environment in the absence of changes are analyzed. Measures are proposed to actualize professional competencies and maintain and increase the level of competitiveness of specialists in the field of risk analysis and economic security in the labor market.
Cross-Platform Spillover Effects in Consumption of Viral Content: A Quasi-Experimental Analysis Using Synthetic Controls
Authors: Krijestorac Haris , Garg Rajiv , Mahajan Vijay
Published: May 2020

To inform product release and distribution strategies, research has analyzed cross-market spillovers in new product adoption. However, models that examine these effects for digital and viral media are still evolving. Given resistance to advertising, firms often seek to promote their own viral content to boost brand awareness. However, a key shortcoming of virality is its ephemeral nature. To gain insight into sustaining virality, we develop a quasi-experimental approach that estimates the backward spillover onto a focal platform by introducing a piece of content onto a new platform. We posit that introducing content to the audience of a new platform can generate word of mouth, which may affect its consumption within an earlier platform. We estimate these spillovers using data on 381 viral videos on 26 platforms (e.g., YouTube, Vimeo) and observe how consumption of videos on an initial “lead” platform is affected by their subsequent introduction onto “lag” platforms. This spillover is estimated as follows: for each multiplatform video, we compare its view growth after being introduced onto a new platform to that of a synthetic control based on similar single-platform videos. Analysis of 275 such spillover scenarios reveals that introducing a video onto a lag platform roughly doubles its subsequent view growth in the lead platform. This positive cross-platform spillover is persistent, bursty, and strongest in the first 42 days. We find that spillover is boosted when the video is consumed more in the lag platform, when the consumption rate peaks earlier in the lag platform, and when the lag platform targets a foreign market. Our findings suggest that firms can sustain the popularity of their viral content by introducing it onto additional platforms (e.g., Vimeo) after posting it on a focal platform (e.g., YouTube). As a result of their posting on the latter platforms, firms can expect subsequent view growth on the focal platform to roughly double. The aforementioned benefits persists for up to five lag platforms. Platforms should also consider that a positive cross-platform spillover may help platforms reinforce each other’s usage, rather than cannibalize each other.
CEO Turnover and Accounting Earnings: The Role of Earnings Persistence
Authors: Suk Inho , Lee Seungwon , Kross William
Published: May 2020

Although earnings persistence should have a nontrivial impact on chief executive officer (CEO) turnover decisions, prior studies have paid little attention to the role of earnings persistence in CEO turnover decisions. This study examines the effect of earnings persistence on the sensitivity (i.e., the negative relation) of CEO turnover to earnings performance. First, we find that the sensitivity of forced CEO turnovers to earnings performance is greater when earnings are more persistent. We also show that among numerous earnings attributes, earnings persistence is the most direct and dominant attribute in explaining CEO turnover-earnings sensitivity. Further, when the effect of earnings persistence on CEO compensation-earnings sensitivity is weak, the effect of earnings persistence on CEO turnover-earnings sensitivity is stronger, suggesting that the executive discipline system substitutes for the compensation system when earnings persistence is neglected by compensation policies. Overall, our findings suggest that earnings persistence plays a crucial role in CEO turnover decisions by elevating the board’s knowledge on the future performance implications of current earnings. Finally, the role of persistence is even more crucial when it is neglected by executive compensation policies.

This paper was accepted by Shiva Rajgopal, accounting.
Managing Supply in the On-Demand Economy: Flexible Workers, Full-Time Employees, or Both?
Authors: Dong Jing , Ibrahim Rouba
Published: May 2020

The rise of the blended workforce, which is identified as one of the top current workplace trends, is prompting firms to reevaluate their staffing strategies. A blended workforce melds as a deliberate business strategy flexible workers (for example, independent contractors or freelancers) with full-time employees. Because flexible workers are free to determine their own work schedules, the supply (total number of workers) is uncertain. In “Managing Supply in the On-Demand Economy: Flexible Workers, Full-Time Employees, or Both?,” Dong and Ibrahim examine the optimal staffing strategy for flexible workers and full-time employees to effectively balance operating costs, time variability in customer demands, and supply-side uncertainty while not compromising on the quality of service offered to customers. This work gleans insights on the appropriateness of alternative workforce models, which are especially relevant for the gig economy.
In vitro antimicrobial effects of chlorhexidine diacetate versus chlorhexidine free base dressings
Authors: Holinga George J. , McGuire James E.
Published: May 2020

Objective:

The aim of this study was to investigate the in vitro antimicrobial performance of a chlorhexidine diacetate dressing and a chlorhexidine free base dressing to determine if the free base form of chlorhexidine has the potential to be an effective alternative to the chlorhexidine salts used in conventional, chlorhexidine-based antimicrobial dressings.

Method:

Dressing samples were inoculated with clinically relevant pathogenic microorganisms including Gram-positive and Gram-negative bacteria, yeasts and fungus, and subsequently evaluated for in vitro log10 reduction at 1-, 3-, and 7-day time points. Chlorhexidine mole content was also calculated as a function of dressing surface area for both sample types to allow for formulation-independent comparison between the dressings.

Results:

The chlorhexidine free base dressing demonstrated >0.5 log10 superior mean antimicrobial efficacy at 67% of the experimental time points and equivalent mean antimicrobial efficacy (≤0.5 log10 different) at the remaining time points when compared with the chlorhexidine diacetate dressing. The chlorhexidine free base dressing was also found to contain 36% less chlorhexidine mole content than the chlorhexidine diacetate dressing.

Conclusion:

Our results suggest that a dressing formulated with chlorhexidine free base can deliver in vitro antimicrobial performance at both a magnitude and rate that meets or exceeds that of a chlorhexidine diacetate-based dressing, while also allowing for a reduction in total chlorhexidine content per dressing. These findings could be of particular interest to researchers developing new antimicrobial technologies as well as to infection preventionists when evaluating antimicrobial products for use on clinical patients at elevated risk of infection.
Elicitation of disease concepts in patients with diabetic foot ulcers: a qualitative study
Authors: Okoro Tony , Sikirica Vanja , Casillas Linda , Brion Triza , Devine Jacob , Ong Vivien , Howard Kellee
Published: May 2020

Objective:

To identify in-depth information directly from patients with diabetic foot ulcers (DFU) on DFU symptoms, impacts on functioning and effects on health-related quality of life (HRQoL).

Method:

Semi-structured, qualitative concept elicitation interviews were conducted with patients with DFUs (Wagner grade 1 or 2) until saturation was reached. Qualitative analysis (using MAXQDA, VERBI GmbH, Germany) of interview transcripts was conducted to identify concepts relevant to patients with DFUs, based on the frequency of mentions, and elucidate themes regarding impacts on HRQoL.

Results:

Of the 18 participants, most were male (n=14; 78%) and 10 (56%) presented with a Wagner grade of 1. Frequently reported symptoms were pain/discomfort (n=15; 83%), weeping/discharge (n=10; 56%), bleeding (n=10; 56%) and swelling (n=8; 44%). Overall, patients reported more impacts than symptoms—wound care/treatment burden (n=14; 78%), limitations on exercise/physical activity (n=13; 72%), mobility limitations (n=12; 67%), and offloading (n=12; 67%) were the most frequently mentioned. Based on findings from the patient interviews, a draft conceptual model was developed outlining interrelationships between DFU symptoms, impacts, and HRQoL from the patient perspective.

Conclusion:

Qualitative interviews captured the breadth of disease-related concepts of direct importance to patients. The draft conceptual model developed from the analysis can help identify measures or instruments for use in assessing patient-reported symptoms or HRQoL in clinical practice and may have wider research applicability, including evaluation of treatment benefits in patients with DFUs.
PROPOSIÇÕES DO PLANO MUNICIPAL DE EDUCAÇÃO DE JATAÍ/GO: INCERTEZAS PARA A FORMAÇÃO E TRABALHO DOCENTE
Authors: Cruvinel Belarmina Vilela , Oliveira Camila Alberto Vicente de , Nez Egeslaine de
Published: May 2020

Esse estudo apresenta o Plano Municipal de Educação (PME) de Jataí/GO destacando as metas e estratégias que se referem à formação e trabalho docente, especificamente no que tangencia a promoção da carreira do profissional da educação. Pretende, ainda, debater essas proposições do PME local tendo por base o Plano Nacional de Educação (PNE) e as incertezas em relação à formação e trabalho docente advindas do monitoramento e avaliação da implementação das metas e estratégias desse Plano. Tendo por base o levantamento documental com abordagem qualitativa, espera-se responder a seguinte problemática: pode o PME de Jataí/GO contribuir para a conformação de uma política educacional local que contribua para o avanço na formação e no trabalho/carreira docente? Percebe-se que o PME em tela tem avançado lentamente no que se refere às condições de trabalho docente minimizando, portanto, a sua relevância e gerando incertezas para a educação de qualidade social no município pesquisado.
“Collaborators” or “Resistors,” “Loyalists” versus “Rebels”: Problematizing Colonial Binary Nomenclatures through the Prism of Dedan Kimathi's Career
Authors: Githuku Nicholas
Published: May 2020

This paper evaluates the “evolution” of African anti-imperial resistance in African history in general and that of Kenya in particular, in the attempt to reveal hidden or private/public transcripts and inherent power dynamics that fueled political dissent, opposition, and action. James C. Scott informs us that people, generally, and especially where relations of power are concerned, do not usually wear their opinions, emotions, motives or deepest thoughts that shape their behavior on their sleeve. Therefore, throughout history, the vast majority of people, the “dissembled weak,” or “those subject to elaborate and systematic forms of social subordination,” are given to putting up “public performances,” a perfunctory adherence to imposed laws, policies, and the status quo as is required of them. The outcome of this general rule of thumb is a “public transcript” that, “by its accommodationist tone,” provides “convincing evidence for the hegemony of dominant values, for the hegemony of dominant discourse.” Such public transcripts are misleading since they lead observers to “conclude that subordinate groups endorse the terms of their subordination and are willing, even enthusiastic, partners in that subordination.” The implications of Scott's insightful paradigmatic conceptualization of the internal dynamics of the “arts of resistance” are far-reaching. This radical conceptualization of the concealed roots of external human behavior, and “public performances,” naturally complicates earlier analysis of social categories of African responses to European imperialism thought to be straightforward and concrete or mutually exclusive. It presents a possibility for an analysis and reinterpretation of the deep psychosociological springs and triggers of human behavior, which necessitates a crucial return to this important theme in African history. That is, a more nuanced scrutiny and critical study of the popular mind or populist reason. This paper is such a critical reexamination of problematic social categories and Eurocentric binary nomenclatures.
Memory and Narrative, Capturing Walter Rodney's Legacy: Interview with Professor Ewart Thomas
Authors: Thomas Ewart , Walcott Carolyn
Published: May 2020

As part of the 2018 Walter Rodney Symposium, Dr. Ewart Thomas, a close childhood and lifelong friend of Walter Rodney and Stanford University professor emeritus, was in attendance to deliver a plenary lecture during a long weekend of events. During his visit to Atlanta, a local graduate student who had been working with the Walter Rodney Foundation Symposium Planning Committee identified her skills in communications and journalism and an upcoming class assignment to do an interview. With the help of the planning committee, its chair and co-chair, Carolyn Walcott was able to arrange an interview with Dr. Thomas, which was part of her final course assignment, and is shared here with only lightly editing.
Navigating the marketisation of community aged care services in rural Australia
Authors: Hodgkin Suzanne , Savy Pauline , Clune Samantha , Mahoney Anne-Marie
Published: May 2020

The aged care policies of many Organisation for Economic Co-operation and Development countries reflect free-market principles. In Australia, the recently introduced Consumer Directed Care programme centres on markets in which a range of organisations compete to provide services to community-living elders. As consumers, older people are allocated government funding with which they select and purchase items from their chosen service organisation. This article presents findings from a case study that explored the impacts of this programme on a group of rurally based, not-for-profit providers and consumers. The findings portray the challenges and advantages associated with providing and accessing services in limited rural markets.
Zonal-based high-performance control in adaptive optics systems with application to astronomy and satellite tracking
Authors: Prengère Lèonard , Kulcsár Caroline , Raynaud Henri-François
Published: May 2020

This paper presents a model-based approach to adaptive optics (AO)
control based on a zonal (i.e., pixelized) representation of the
incoming atmospheric turbulence. Describing the turbulence on a zonal
basis enables the encapsulation of the standard frozen-flow assumption
into a control-oriented model. A multilayer zonal model is proposed
for single-conjugate AO (SCAO) systems. It includes an edge
compensation mechanism involving limited support, which results in a
sparser model structure. To further reduce the computational
complexity, new resultant zonal models localized in the telescope
pupil are proposed, with AR1 or AR2 structures, that match the spatial
and temporal cross-correlations of the incoming turbulence. The global
performance of the resulting linear quadratic Gaussian (LQG) regulator
is evaluated using end-to-end simulations and compared to several
existing controllers for two different configurations: a very large
telescope SCAO and low earth orbit satellite tracking. The results
show the high potential of the new approach and highlight possible
trade-offs between the performance and complexity.
Robust design method for metasurface high-sensitivity sensors and absorbers
Authors: Rastgordani Amin , Ghattan Kashani Zahra
Published: May 2020

In this study, we propose and investigate a generalized circuit model for metasurface high-sensitivity sensors and broadband absorbers. First, we propose a terahertz tunable and polarization-independent high-sensitivity sensor based on a bulk Dirac semimetal metasurface. We compare the results of the proposed circuit model with those of full-wave simulation. In addition, we achieve the spectra of the sensor absorption for healthy and cancer cells. Moreover, since for most practical applications, the absorption bandwidth is one of the most substantial metrics, we propose a broadband absorber in the wavelength range of 600 to 800 nm. To verify our proposed model, we compare the results of the circuit model with those of experimental data. Additionally, a good agreement is observed among the results of the circuit model, those of full-wave simulations, and the experimental data. The proposed circuit model is general. It provides physical insight into the design and operation of various sub-wavelength structures in the broad frequency range. In addition, the proposed sensor can be used as a platform for the design of sensors needed in various chemical and biomedical systems.
Characterization of integrated waveguides by atomic-force-microscopy-assisted mid-infrared imaging and spectroscopy
Authors: Gallacher Kevin , Millar Ross W. , Paul Douglas J. , Frigerio Jacopo , Ballabio Andrea , Isella Giovanni , Rusconi Francesco , Biagioni Paolo , Giliberti Valeria , Sorgi Alessia , Baldassarre Leonetta , Ortolani Michele
Published: May 2020

A novel spectroscopy technique to enable the rapid characterization of discrete mid-infrared integrated photonic waveguides is demonstrated. The technique utilizes lithography patterned polymer blocks that absorb light strongly within the molecular fingerprint region. These act as integrated waveguide detectors when combined with an atomic force microscope that measures the photothermal expansion when infrared light is guided to the block. As a proof of concept, the technique is used to experimentally characterize propagation loss and grating coupler response of Ge-on-Si waveguides at wavelengths from 6 to 10 µm. In addition, when the microscope is operated in scanning mode at fixed wavelength, the guided mode exiting the output facet is imaged with a lateral resolution better than 500 nm i.e. below the diffraction limit. The characterization technique can be applied to any mid-infrared waveguide platform and can provide non-destructive in-situ testing of discrete waveguide components.
Full control of dual-band vortex beams using a high-efficiency single-layer bi-spectral 2-bit coding metasurface
Authors: Xin Mingbo , Xie Rensheng , Zhai Guohua , Gao Jianjun , Zhang Dajun , Wang Xiong , An Sensong , Zheng Bowen , Zhang Hualiang , Ding Jun
Published: May 2020

Vortex beams (VBs) carrying orbital angular moment (OAM) modes have been proven to be promising resources for increasing communication capacity. Although considerable attention has been paid on metasurface-based VB generators due to the unprecedented advantages of metasurface, most applications are usually limited at a single band with a fixed OAM mode. In this work, an emerging dual-band reflection-type coding metasurface is proposed to mitigate these issues by newly engineered meta-atoms, which could achieve independent 2-bit phase modulations at two frequency bands. The proposed coding metasurface could efficiently realize and fully control dual-band VBs carrying frequency selective OAM modes under the linearly polarized incidence. As the first illustrative example, a dual-band VB generator with normal beam direction is fabricated and characterized at two widely used communication bands (Ku and Ka bands). Moreover, by encoding proper coding sequences, versatile beams carrying frequency selective OAM modes can be achieved. Therefore, by adding a gradient phase sequence to the first VB generator, the second one is designed to steer the generated beams to a preset direction, which could enable diverse scenarios. The measurement results of both VB generators agree very well with the numerical ones, validating the full control capability of the proposed approach.
Manipulating far-zone scattered field by convolution of different types of weight function
Authors: Pan Xiaoning , Cheng Ke , Ji Xiaoling , Wang Tao
Published: May 2020

A method of convolution of two weight functions to design new types of scattering medium is proposed, and two novel media models are illustrated in detail. The first one is that the two functions involved in convolution are the same type with different parameters. In this case, the far-zone scattered spectral intensity will maintain a stable shape, but the profile size can be controlled by changing the value of parameters. The second one is that the two functions involved in convolution are different types. In this case, the profile of far-zone scattered spectral intensity depends not only on the type of the weight functions but also on the value of the parameters in each weight function. By examining the scattered property of these media, we demonstrate that various far-zone scattered spectral density, such as rectangular distribution and circular distribution, can be achieved. The method proposed in this manuscript may have potential applications in the manipulation of the far-zone scattered field.
Platinum substrate for surface plasmon microscopy at small angles
Authors: Hassani Hossein , Wolf Nikolaus Radja , Yuan Xiaobo , Wördenweber Roger , Offenhäusser Andreas
Published: May 2020

Platinum is reported as the main component of the substrate in surface plasmon microscopy of the metal−dielectric interface for small-angle measurements. In the absence of a narrow dip in the angular spectrum of platinum, the refractive index of the dielectric medium or the thickness of a deposited layer is proven deducible from the observed sharp peak, close to the critical angle. The sensitivities of refractive index and thickness measurements using platinum are compared with that of a gold surface plasmon resonance chip. Furthermore, the thickness of a structured layer of (3-Aminopropyl)triethoxysilane on the platinum substrate is measured to be 0.7 nm, demonstrating the high sensitivity of the technique.
Shift of zero-field level-crossing resonance in the Cs D1 line and its use in vector magnetometry
Authors: Brazhnikov Denis , Ignatovich Stepan , Mesenzova Irina , Novokreshchenov Alexey , Goncharov Andrei
Published: May 2020

We examine the level-crossing resonance in a cesium vapor cell filled with a buffer gas under counterpropagating pump and probe light waves with orthogonal linear polarizations. An optical transition

F
g

=
4
→

F
e

=
3

is excited in the

D

1

line. Probe-wave transmission is analyzed versus a static magnetic field applied along the wave vectors. This configuration can provide ultrahigh-contrast electromagnetically induced absorption resonances. We report here a new, to the best of our knowledge, magneto-optical effect in the resonance shift caused by a transverse magnetic field and discuss how it can be applied in vector magnetometry.
Nonreciprocal cavities and the time-bandwidth limit: comment
Authors: Tsakmakidis Kosmas L. , You Yun , Stefański Tomasz , Shen Linfang
Published: May 2020

In their paper in Optica 6, 104
(2019)OPTIC82334-253610.1364/OPTICA.6.000104, Mann et al. claim that linear, time-invariant
nonreciprocal structures cannot overcome the time-bandwidth limit and
do not exhibit an advantage over their reciprocal counterparts,
specifically with regard to their time-bandwidth performance. In this
Comment, we argue that these conclusions are unfounded. On the basis
of both rigorous full-wave simulations and insightful physical
justifications, we explain that the temporal coupled-mode theory, on
which Mann et al. base their main
conclusions, is not suited for the study of nonreciprocal trapped
states, and instead direct numerical solutions of Maxwell’s equations
are required. Based on such an analysis, we show that a nonreciprocal
terminated waveguide, resulting in a trapped state, clearly
outperforms its reciprocal counterpart; i.e., both the extraordinary
time-bandwidth performance and the large field enhancements observed
in such modes are a direct consequence of nonreciprocity.
Serpentine optical phased arrays for scalable integrated photonic lidar beam steering
Authors: Dostart Nathan , Zhang Bohan , Khilo Anatol , Brand Michael , Al Qubaisi Kenaish , Onural Deniz , Feldkhun Daniel , Wagner Kelvin H. , Popović Miloš A.
Published: May 2020

Optical phased arrays (OPAs) implemented in integrated photonic
circuits could enable a variety of 3D sensing, imaging, illumination,
and ranging applications, and their convergence in new lidar
technology. However, current integrated OPA approaches do not scale—in
control complexity, power consumption, or optical efficiency—to the
large aperture sizes needed to support medium- to long-range lidar. We
present the serpentine OPA (SOPA), a new OPA concept that addresses
these fundamental challenges and enables architectures that scale up
to large apertures. The SOPA is based on a serially interconnected
array of low-loss grating waveguides and supports fully passive, 2D
wavelength-controlled beam steering. A fundamentally space-efficient
design that folds the feed network into the aperture also enables
scalable tiling of SOPAs into large apertures with a high fill-factor.
We experimentally demonstrate, to the best of our knowledge, the first
SOPA using a 1450–1650 nm wavelength sweep to produce 16,500
addressable spots in a

27
×
610

array. We also demonstrate, for the
first time, far-field interference of beams from two separate OPAs on
a single silicon photonic chip, as an initial step towards long-range
computational imaging lidar based on novel active aperture
synthesis schemes.
Demonstration of simultaneous quantum steering by multiple observers via sequential weak measurements
Authors: Choi Yeon-Ho , Hong Seongjin , Pramanik Tanumoy , Lim Hyang-Tag , Kim Yong-Su , Jung Hojoong , Han Sang-Wook , Moon Sung , Cho Young-Wook
Published: May 2020

Quantum correlation is a fundamental resource for various quantum information tasks. It is thus of importance to share the correlation to utilize it for many parties, but sharing quantum correlation among multiple parties is strictly restricted by the well-known monogamy relations. Nonetheless, this restriction can be relaxed when weak measurements are employed. Here, we experimentally demonstrate multiple-observer quantum steering by exploiting sequential weak measurements. Specifically, we observe simultaneous triple violations of the quantum steering inequality among four observers for a bipartite entangled system. Our results not only provide fundamental insights into the relation between quantum steering and measurement disturbance, but also suggest that quantum steering might be repeatably exploited to find applications to, for example, unbounded randomness certification and sharing secret keys among multiple parties simultaneously.
Francisco Dias Gomes. Duas tragédias clássicas: Ifigénia e Electra
Authors: Bernardes José Augusto Cardoso , Silva Maria de Fátima , Brasete Maria Fernanda
Published: May 2020

A obra inclui um estudo introdutório sobre a receção de temas do teatro clássico na produção dos membros da Arcádia Lusitana, em geral, para situar a produção de Francisco Dias Gomes. Segue-se-lhe a edição de duas tragédias Ifigénia e Electra, em ambos os casos acompanhada de um amplo estudo introdutório, cujo objetivo central e o de identificar a relação entre as produções oitocentistas e os seus modelos da Antiguidade grega
Prevalence of virulence factor, antibiotic resistance, and serotype genes of Pasteurella multocida strains isolated from pigs in Vietnam
Authors: Vu-Khac Hung , Trinh T. T. Hang , Nguyen T. T. Giang , Nguyen X. Truong , Nguyen Thi Thinh
Published: May 2020

Aim: The study was conducted to determine the prevalence and characterization of the Pasteurella multocida isolates from suspected pigs in Vietnam.

Materials and Methods: A total of 83 P. multocida strains were isolated from lung samples and nasal swabs collected from pigs associated with pneumonia, progressive atrophic rhinitis, or reproductive and respiratory symptoms. Isolates were subjected to multiplex polymerase chain reaction (PCR) for capsular typing, detection of virulence-associated genes and antibiotic resistance genes by PCR. The antimicrobial sensitivity profiles of the isolates were tested by disk diffusion method.

Results: All the isolates 83/83 (100%) were identified as P. multocida by PCR: serogroup A was obtained from 40/83 (48.19%), serogroup D was detected from 24/83 strains (28.91%), and serogroup B was found in 19/83 (22.35%) isolates. The presence of 14 virulence genes was reported including adhesins group (ptfA – 93.97%, pfhA – 93.97%, and fimA – 90.36%), iron acquisition (exbB – 100%, and exbD – 85.54%), hyaluronidase (pmHAS – 84.33%), and protectins (ompA – 56.62%, ompH 68.67%, and oma87 – 100%). The dermonecrotoxin toxA had low prevalence (19.28%). The antimicrobial susceptibility testing revealed that cephalexin, cefotaxime, ceftriaxone, ofloxacin, pefloxacin, ciprofloxacin, and enrofloxacin were the drugs most likely active against P. multocida while amoxicillin and tetracycline were inactive. The usage of PCR revealed that 63/83 isolates were carrying at least one of the drug resistance genes.

Conclusion: Unlike other parts of the word, serotype B was prevalent among Vietnamese porcine P. multocida strains. The high antibiotic resistance detected among these isolates gives us an alert about the current state of imprudent antibiotic usage in controlling the pathogenic bacteria.
Sensitivity of polymerase chain reaction in the detection of rat meat adulteration of beef meatballs in Indonesia
Authors: Suryawan G. Y. , Suardana I. W. , Wandia I. N.
Published: May 2020

Background and Aim: Meatballs are a processed product of animal origin that is consumed cooked, usually with chicken, beef, or pork as the main ingredient. Unfortunately, some unscrupulous sellers in Indonesia may adulterate this product with rat meat to decrease production costs. Rat meat in any food is a critical public health issue and is prohibited under Indonesian food safety laws, as well as within Muslim communities. This study aimed to test the sensitivity of the polymerase chain reaction (PCR) method in the detection of rat meat contained in processed, cooked beef meatballs.

Materials and Methods: Beef meatballs were formulated with different concentrations of rat meat. Molecular detection of adulteration was initiated by DNA extraction of each cooked meatball formulation followed by PCR using a specific primer for mitochondrial DNA Cytochrome b gene of rat, which primer sequences, i.e., forward primer: 5'CATGGGGACGAGGACTATACTATG '3 and reverse primer: 5'GTAGTCCCAATGTAAGGGATAGCTG'3.

Results: Our study showed that the PCR method is sensitive in detecting 5% or greater rat meat adulteration of cooked beef meatballs.

Conclusion: The PCR method can be used to detect most rat meat adulteration of cooked beef meatballs and offers a sensitive and effective means to protect food safety and religious requirements in Indonesia.
Análise multivariada aplicada ao estudo hidroquímico das águas subterrânea na bacia sedimentar do Araripe – CE
Authors: Costa Celme Torres F da , Bezerra João Emerson Celestino Dias , Paula Filho Francisco José de , Firmino Paulo Renato Alves , Souza Rosilda Benício de
Published: May 2020

A gestão das águas subterrâneas geralmente envolve a determinação de muitas variáveis para caracterizar a qualidade da água. Essas variáveis, por serem fortemente correlacionadas entre si dificultam o entendimento de suas inter-relações, dependência e importância. A aplicação de um modelo de análise multivariada permitiu reduzir o número de atributos e variáveis, indicar as que são responsáveis pela dispersão das observações e evidenciar as principais variáveis que compõem o processo de caracterização da qualidade da água, sendo esse o objeto do estudo, apresentado nessa investigação, para as águas subterrâneas da bacia Sedimentar do Araripe. A partir dos resultados foi possível observar que as características das águas estão relacionadas com a formação geológica dos poços monitorados. Portanto, medidas de monitoramento podem ser realizadas com base nos elementos hidroquímicos determinantes da qualidade das águas (CE, STD, Ca2+, Mg2+, Cl-, SO4, Fe, pH e HCO3) identificados pela análise de componentes principais. Estas medidas podem ser voltadas para conservação dos solos e melhor uso das águas subterrâneas na área em estudo. Procedimentos de inferir as principais variáveis para determinação da qualidade da água subterrânea corroboram com o processo de gestão de recursos hídricos, principalmente nas atividades de monitoramento e de utilização dos mananciais hídricos
Monitoring analysis of two pavement sections of highway BR-448/RS included in the Asphalt Thematic Network Project
Authors: Kern Camila , Bock André Luiz , Núñez Washington Peres , Ceratti Jorge Augusto Pereira
Published: May 2020

Highways are the mode of transport used for the transportation of the majority of loads and passengers in Brazil; however, the lack of conservation of pavements has caused several economical losses to the country. Only through suitable pavement management the rehabilitation measures taken might ensure a satisfactory level of service. The present research aimed at evaluating the performance of two pavement sections of the federal highway BR-448/RS, in southern Brazil. For three years, the evolution of the pavement structural capacity and functional condition were followed in order to propose performance trends. Deflections, permanent deformations, and surface defects surveys scarcely varied and were quite low due to the thick asphalt layers used (19 cm). On the other hand, segregation of the asphalt mixture was observed when the final layer was laid. That segregation affected pavement texture, reduced tire-road friction, and caused the formation of surface water films; thus, reducing the road safety. In general, the proposed trend lines predicted quite accurately the pavement performance throughout the period evaluated and will be used in the MeDiNa software database for the creation of a new Brazilian pavement design method.
Employing particle swarm optimization algorithm for shrinkage parameter estimation in generalized Liu estimator
Authors: Abdulkareem Abdulazeez Qamar , Yahya Algamal Zakariya
Published: May 2020

It is well-known that in the presence of multicollinearity, the Liu estimator is an alternative to the ordinary least square (OLS) estimator and the ridge estimator. Generalized Liu estimator (GLE) is a generalization of the Liu estimator. However, the efficiency of GLE depends on appropriately choosing the shrinkage parameter matrix which is involved in the GLE. In this paper, a particle swarm optimization method, which is a metaheuristic continuous algorithm, is proposed to estimate the shrinkage parameter matrix. The simulation study and real application results show the superior performance of the proposed method in terms of prediction error.Â Â Â
History of the Indiana Geological and Water Survey
Authors: DeChurch Deborah A.
Published: May 2020

Not an abstract, per se, but the opening paragraph.

The early years of the Survey’s history (1837–1986) is taken, almost verbatim, from an article written by John B. Patton (Director and State Geologist from 1959–86) (Patton, 1988). Information from later years is from various sources: the Hester years from a piece by John R. Hill (IGS Geologist and Assistant Director from 1970 to 2007) and the Steinmetz years from the reminiscences of John C. Steinmetz (Director, 1998–2015). It also includes various facts taken from Landmarks in Indiana Geology—A Timeline, an online visual history by Henry H. Gray. These various pieces were edited and expanded upon by Deborah A. DeChurch (IGWS Editor, 1992–2020), with the assistance of Nancy R. Hasenmueller, Barbara T. Hill, Jenna Lanman, Polly R. Sturgeon, and Todd A. Thompson. We also relied upon the institutional memories of other staff members.
Impact of Team Formation Method on Student Performance, Attitudes, and Behaviors
Authors: Post Martiqua L , Barrett Anthony , Williams Marlyse , Scharff Lauren
Published: May 2020

This project examined the effects of two team selection methods (self-selected and instructor-formed based on matched academic performance) on team and individual student performance and on self-reported attitudes and team behaviors in a freshman-level core-required introductory engineering course. The inclusion of both mid and end-of-semester self-reports provided some insights on the development of team dynamics, and because self-report data were not anonymous, correlations could be performed between the self-report and performance data. Matched-performance groups had significantly higher grades on several performance measures, with a larger effect on the team grades than on the individual grades; however, overall the effect sizes were small. There were no group differences for most self-reported items, although a key finding was that self-selected teams were significantly more likely to already have friends on their team, and a significant correlation showed that already having friends on a team was negatively correlated with many of the performance measures. In contrast, members of both types of teams reported equally high likelihood to make new friends, which was positively correlated with performance. For both groups there were small but significant decreases from mid to end of semester in satisfaction with team formation method, general enjoyment, and task-orientation over time. All of these time-related factors also showed significant correlations with the performance measures. Therefore, these factors seem like natural points for instructor attention when using teams. Understanding the impact of different approaches to team formation may guide instructors and lead to more well-functioning teams, higher student learning, and greater student satisfaction.
Exploring Organic Chemistry I students’ responses to an exam wrapper intervention.
Authors: Grandoit Evan , Bergdoll Rose , Rosales Edith , Turbeville David , Mayer Shoshana , Horowitz Gail
Published: May 2020

Abstract: Research has demonstrated that academically successful students are effective, self-regulated learners. Moreover, exam wrapper interventions have been shown to foster the development of self-regulated learning behaviors on the part of college students. In this naturalistic, qualitative, and exploratory study, an exam wrapper intervention was implemented in a key, gatekeeping STEM course at a diverse, public university. Student responses to a series of four exam wrappers were collected and analyzed. Results indicated that while many students were able to look critically at their study behaviors and course performance, these behaviors did not necessarily pay off, especially for weaker students. Notably, transfer and/or non-matriculated students were at greatest risk of withdrawal and failure. However all students, both weak and strong, showed a lack of attention towards checking their answers and learning from their mistakes. Overall, the exam wrappers provided useful information regarding the SRL processes of these STEM students.