Dynamic externalities and regional manufacturing development: An exploration of the Polish experience before and after 1989

The impact of localization and urbanization economies on regional manufacturing development in Poland 1976-96 is assessed in terms of employment and the regional convergence or divergence of the economy. We examine current research on the role of dynamic production externalities in regional manufacturing development, starting with a review of recent literature on the nature of such externalities in manufacturing location, and how positive externalities may influence the spatial clustering of manufacturing industries. While much of the current literature is focussed on US experience, we analyse manufacturing employment data for Poland, in order to explore to what extent conclusions drawn from US experience may illuminate a regional economy in transition. The analysis also pays attention to the integration of a number of different methods from differing traditions, from economic geography, regional science, and new economic geography, including location quotients, Gini indices, shift-share, analysis of variance, Poisson regression, and Poisson regression for panel data. We find that radical changes have occurred in patterns of Polish regional manufacturing employment, both with regard to sectors and regions. Transition is refocussing the regional economy on strong regional centres, and on sectors regarded with little favour in the planned economy, such as food processing and wood products, including furniture.

The Effect of Exercise on College Students\u27 Overall Health

Introduction: Many individuals are not attaining the World Health Organization and American Heart Association’s recommendations for daily physical activity. Physical activity habits are developed during young adulthood and it is therefore important to study barriers to physical activity in college students. Objectives: Investigate the relationship between college student’s physical activity and their overall health. Methods: Data was collected by circulating an online survey to students on the University of South Dakota campus. Several survey questions were used from the SF-36 and the National College Health Assessment. Measures included mental health, physical activity, overall health, diet, and sleep habits. Results: Results showed a positive relationship between physical activity and perceived mental and physical health. Physical activity rates declined from high school to college according to self-reported measures. Healthy eating habits were correlated with a higher rate of physical activity and perceived better health. Sleeping habits were not found to be correlated with physical activity rates and perceived health. Conclusion: I recommend colleges provide more cost effective and accessible physical activity options for students

Dynamic externalities and regional manufacturing development: An exploration of the Polish experience before and after 1989

The impact of localization and urbanization economies on regional manufacturing development in Poland 1976-96 is assessed in terms of employment and the regional convergence or divergence of the economy. We examine current research on the role of dynamic production externalities in regional manufacturing development, starting with a review of recent literature on the nature of such externalities in manufacturing location, and how positive externalities may influence the spatial clustering of manufacturing industries. While much of the current literature is focussed on US experience, we analyse manufacturing employment data for Poland, in order to explore to what extent conclusions drawn from US experience may illuminate a regional economy in transition. The analysis also pays attention to the integration of a number of different methods from differing traditions, from economic geography, regional science, and new economic geography, including location quotients, Gini indices, shift-share, analysis of variance, Poisson regression, and Poisson regression for panel data. We find that radical changes have occurred in patterns of Polish regional manufacturing employment, both with regard to sectors and regions. Transition is refocussing the regional economy on strong regional centres, and on sectors regarded with little favour in the planned economy, such as food processing and wood products, including furniture

The variability patterns of the TeV blazar PG 1553+113 from a decade of MAGIC and multi-band observations

PG 1553+113 is one of the few blazars with a convincing quasi-periodic emission in the gamma-ray band. The source is also a very high-energy (VHE; >100 GeV) gamma-ray emitter. To better understand its properties and identify the underlying physical processes driving its variability, the MAGIC Collaboration initiated a multiyear, multiwavelength monitoring campaign in 2015 involving the OVRO 40-m and Medicina radio telescopes, REM, KVA, and the MAGIC telescopes, Swift and Fermi satellites, and the WEBT network. The analysis presented in this paper uses data until 2017 and focuses on the characterization of the variability. The gamma-ray data show a (hint of a) periodic signal compatible with literature, but the X-ray and VHE gamma-ray data do not show statistical evidence for a periodic signal. In other bands, the data are compatible with the gamma-ray period, but with a relatively high p-value. The complex connection between the low and high-energy emission and the non-monochromatic modulation and changes in flux suggests that a simple one-zone model is unable to explain all the variability. Instead, a model including a periodic component along with multiple emission zones is required.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical Society. 19 pages, 9 figures. Corresponding authors: Elisa Prandini, Antonio Stamerra, Talvikki Hovatt

The variability patterns of the TeV blazar PG 1553 + 113 from a decade of MAGIC and multiband observations

PG 1553 + 113 is one of the few blazars with a convincing quasi-periodic emission in the gamma-ray band. The source is also a very high energy (VHE; >100 GeV) gamma-ray emitter. To better understand its properties and identify the underlying physical processes driving its variability, the MAGIC Collaboration initiated a multiyear, multiwavelength monitoring campaign in 2015 involving the OVRO 40-m and Medicina radio telescopes, REM, KVA, and the MAGIC telescopes, Swift and Fermi satellites, and the WEBT network. The analysis presented in this paper uses data until 2017 and focuses on the characterization of the variability. The gamma-ray data show a (hint of a) periodic signal compatible with literature, but the X-ray and VHE gamma-ray data do not show statistical evidence for a periodic signal. In other bands, the data are compatible with the gamma-ray period, but with a relatively high p-value. The complex connection between the low- and high-energy emission and the non-monochromatic modulation and changes in flux suggests that a simple one-zone model is unable to explain all the variability. Instead, a model including a periodic component along with multiple emission zones is required

Multimessenger Characterization of Markarian 501 during Historically Low X-Ray and γ-Ray Activity

We study the broadband emission of Mrk 501 using multiwavelength observations from 2017 to 2020 performed with a multitude of instruments, involving, among others, MAGIC, Fermi's Large Area Telescope (LAT), NuSTAR, Swift, GASP-WEBT, and the Owens Valley Radio Observatory. Mrk 501 showed an extremely low broadband activity, which may help to unravel its baseline emission. Nonetheless, significant flux variations are detected at all wave bands, with the highest occurring at X-rays and very-high-energy (VHE) 3-rays. A significant correlation (>3σ) between X-rays and VHE 3-rays is measured, supporting leptonic scenarios to explain the variable parts of the emission, also during low activity. This is further supported when we extend our data from 2008 to 2020, and identify, for the first time, significant correlations between the Swift X-Ray Telescope and Fermi-LAT. We additionally find correlations between high-energy 3-rays and radio, with the radio lagging by more than 100 days, placing the 3-ray emission zone upstream of the radio-bright regions in the jet. Furthermore, Mrk 501 showed a historically low activity in X-rays and VHE 3-rays from mid-2017 to mid-2019 with a stable VHE flux (>0.2 TeV) of 5% the emission of the Crab Nebula. The broadband spectral energy distribution (SED) of this 2 yr long low state, the potential baseline emission of Mrk 501, can be characterized with one-zone leptonic models, and with (lepto)-hadronic models fulfilling neutrino flux constraints from IceCube. We explore the time evolution of the SED toward the low state, revealing that the stable baseline emission may be ascribed to a standing shock, and the variable emission to an additional expanding or traveling shock. © 2023. The Author(s). Published by the American Astronomical Society

Multi-messenger characterization of Mrk 501 during historically low X-ray and γ\gamma-ray activity

We study the broadband emission of Mrk 501 using multi-wavelength observations from 2017 to 2020 performed with a multitude of instruments, involving, among others, MAGIC, Fermi-LAT, NuSTAR, Swift, GASP-WEBT, and OVRO. Mrk 501 showed an extremely low broadband activity, which may help to unravel its baseline emission. Nonetheless, significant flux variations are detected at all wavebands, with the highest occurring at X-rays and very-high-energy (VHE) $\gamma$-rays. A significant correlation ($>$3$\sigma$) between X-rays and VHE $\gamma$-rays is measured, supporting leptonic scenarios to explain the variable parts of the emission, also during low activity. This is further supported when we extend our data from 2008 to 2020, and identify, for the first time, significant correlations between Swift-XRT and Fermi-LAT. We additionally find correlations between high-energy $\gamma$-rays and radio, with the radio lagging by more than 100 days, placing the $\gamma$-ray emission zone upstream of the radio-bright regions in the jet. Furthermore, Mrk 501 showed a historically low activity in X-rays and VHE $\gamma$-rays from mid-2017 to mid-2019 with a stable VHE flux ($>$0.2 TeV) of 5% the emission of the Crab Nebula. The broadband spectral energy distribution (SED) of this 2-year-long low-state, the potential baseline emission of Mrk 501, can be characterized with one-zone leptonic models, and with (lepto)-hadronic models fulfilling neutrino flux constraints from IceCube. We explore the time evolution of the SED towards the low-state, revealing that the stable baseline emission may be ascribed to a standing shock, and the variable emission to an additional expanding or traveling shock.Comment: 56 pages, 30 figures, 14 tables, submitted. Corresponding authors are L. Heckmann, D. Paneque, S. Gasparyan, M. Cerruti, and N. Sahakya

Populationsdynamik des Cydia pomonella Granulovirus

Das Cydia pomonella Granulovirus (CpGV, Fam. Baculoviridae) ist ein sehr virulentes und hoch spezifisches Pathogen des Apfelwicklers ( Cydia pomonella), das seit mehreren Jahren in der Bundesrepublik Deutschland und anderen Ländern der EU als Insektizid zugelassen ist. Wie andere Baculoviren auch befällt es die Larven der Insekten und ist aufgrund seiner Selektivität für Nicht-Zielorganismen unbedenklich. In der Vergangenheit konzentrierte sich die Erforschung des CpGV auf Bereiche, die für die Anwendung im Pflanzenschutz relevant waren, wobei nach fast 20 Jahren nach der ersten Zulassung noch immer nicht bekannt ist, ob und wie sich das CpGV in der Umwelt etablieren kann. Im Rahmen der vorliegenden Arbeit wurden verschiedene Parameter, mit deren Hilfe die Populationsdynamik des CpGV beschrieben werden kann, analysiert und quantitativ bestimmt. Neben den biologischen Eigenschaften wie Virulenz, DNA-Charakterisierung und Quantifizierung der Virusnachkommenschaft wurden insbesondere die horizontale sowie die vertikale Transmission, die Inaktivierung und die Infektion später Larvenstadien untersucht. Letztlich wurden die ermittelten Parameter zusammen mit Daten aus der Literatur in ein mathematisches Modell integriert. Um die Wahrscheinlichkeit der horizontalen Transmission zu quantifizieren, wurde ein Modellsystem mit losen Äpfeln etabliert, in dem verschiedene Szenarien möglicher horizontaler Transmission unter definierten Laborbedingungen getestet wurden. In Versuchsserien, in denen ein Virusfleck, entsprechend der produzierten Virusmenge einer Eilarve, auf einen Apfel appliziert worden war, war unter den aufgesetzten Apfelwicklerlarven lediglich eine sehr geringe Mortalität von 3 - 6% zu beobachten. Wurde jedoch ein an einer Virusinfektion gestorbener Larvenkadaver als Inokulum verwendet, lag die Mortalitätsrate aufgesetzter Larven bei über 40%. Diese beobachtete hohe horizontale Transmissionsrate konnte mit dem Verhalten der Larven erklärt werden. Die Larven zeigten eine deutliche Einbohrpräferenz für den Stielansatz bzw. den Kelch, wodurch die Wahrscheinlichkeit des Zusammentreffens einer an der Infektion verendeten Larve mit einer gesunden Larve um ein Vielfaches zunahm. In einem ähnlich angelegten Freilandversuch konnte eine horizontale Transmission nicht belegt werden. Der Unterschied zur Kontrollgruppe fiel aufgrund einer hohen natürlichen Mortalität und einer damit einhergehenden niedrigen Dichte der Larven zu gering aus. Parallel hierzu wurde außerdem eine Halbwertszeit von 52 Sonnenstunden für das CpGV ermittelt. Weiterhin konnte festgestellt werden, dass die Mortalität von späteren Larvenstadien, die 14 Tage Zeit hatten sich in die Äpfel einzubohren, bevor eine CpGV-Applikation durchgeführt wurde, ebenso hoch war wie bei Larven, die sich im L1-Stadium auf der Apfeloberfläche infizierten. Aufgrund des höheren Alters jener Larven war der Fraßschaden an befallenen Äpfeln jedoch wesentlich größer und vergleichbar mit dem Fraßschaden einer unbehandelten Kontrolle. Der Versuch zur vertikalen Transmission zeigte dass, obwohl die verwendete Apfelwicklerzucht nicht frei von CpGV war, die Mortalitätsrate der Nachkommen subletal infizierter Weibchen (44%) jedoch deutlich höher war als die der Nachkommen subletal infizierter Männchen (28%) und der unbehandelten Kontrolle (27%). Auch in den PCR-Analysen konnte eine größere Menge an CpGV-Trägern bei den Nachkommen subletal infizierter Weibchen (67%) als bei den Nachkommen subletal infizierter Männchen (49%) und bei der Kontrolle (42%) nachgewiesen werden. Die Ergebnisse deuten darauf hin, dass eine Infektion durch subletal infizierte Weibchen vertikal in die nächste Generation übertragen werden kann. Dies lässt erkennen, dass in der Folgegeneration des Apfelwicklers eine zusätzliche Wirkung des CpGV durch vertikale Transmission auftreten kann. Hierin wäre auch ein potentieller Mechanismus für eine dauerhafte Etablierung des Virus zu sehen. Letztlich wurden alle Parameter, die die CpGV-Apfelwickler-Beziehung beschreiben, in ein mathematisches Modell GRANULO integriert. Nach einer Sensitivitätsanalyse wurde GRANULO teilweise mit Daten aus den Freilandversuchen verifiziert. Durch Modifikation der Virusparameter im Modell konnte anschließend der Einfluss veränderter biologischer Eigenschaften (UV-Stabilität und Transmissionsraten) der Viren in Simulationen theoretisch erprobt werden. Das beschriebene Modell, das allerdings noch einer weitergehenden Verifizierung und Validierung bedarf, ist eine erste Annäherung an die quantitative Erfassung und Modellierung der Populationsdynamik des Systems CpGV-Apfelwickler. Die im Zusammenhang mit der Populationsdynamik des Apfelwicklers erhobenen Daten können einen wertvollen Beitrag zur Optimierung von Kontrollstrategien des Apfelwicklers mittels CpGV leisten. Außerdem geben sie Aufschluss über die Etablierungsmöglichkeiten dieses Bioinsektizids.The Cydia pomonella granulovirus (CpGV, Fam. Baculoviridae), an extremely virulent and highly specific pathogen, has been registered for the control of the codling moth (Cydia pomonella) in Germany and other countries of the EU. It infects the larval stages of its host and does not harm non target organisms. Past research on CpGV addressed questions relevant to its production and application as pest control agent. However, 20 years after the first registration, it remains unclear whether CpGV can establish itself in the environment. As part of this project, various parameters were analysed and quantified to aid in describing CpGV’s population dynamics. The studied parameters included virulence, virus yield, horizontal and vertical transmission, inactivation rate and the infection rate of late instars. The quantified parameters were then integrated into a mathematical model along with data found in the relevant literature. Detached apples served as model system to test various scenarios of horizontal transmission under laboratory conditions. In a series of experiments a drop of virus suspension that contained an amount of virus, which corresponded to the virus yield of a young larva, was applied to the apple’s surface as the source of infection. Larvae exposed to these apples had a relatively low mortality of 3-6 %. However, when using larval cadavers as a source of infection, horizontal transmission was found to be as high as 40%. This observation could be explained with the larval behaviour. Larvae exhibited a feeding preference near the stalk and in the calyx, thus greatly increasing the probability of coming into contact with an infectious larval cadaver. A similarly set up field experiment could not corroborate the laboratory results, as no significant difference could be detected between the experimental and the control group. A high natural mortality of the larvae under field conditions accounted for a much lower host density compared to the experiments using detached apples. This low host density consequently decreased the probability for horizontal transmission. A second control group also indicated a relatively long persistence of CpGV. A coinciding experiment supported this observation and estimated the half-life of CpGV to be 52 hours exposure to sunlight. A further field experiment showed that there was substantial virus related mortality if larvae were allowed to feed on apples for 14 days prior to the CpGV treatment. The mortality in this group and of larvae that were treated with CpGV in the first instar stage did not differ statistically, although there was more damage due to the increased age of the dying larvae. The experiment on vertical transmission revealed that at the time of the experiment the insect stock was contaminated with CpGV. It also showed that the mortality rate of the offspring of sublethally infected males (28%) did not differ from the offspring of the untreated control animals (27%), whereas the mortality rate of the offspring of sublethally infected females appeared to be higher (44%). This finding was also corroborated by PCR analysis and suggests that CpGV is transmitted vertically via females. In terms of plant protection, CpGV could thus also affect subsequent codling moth generations in addition to the targeted generation. Moreover, vertical transmission could prove to play an important role in the persistence of CpGV in the field. The investigated parameters were integrated into the mathematical model, GRANULO, along with parameters taken from literature. After a sensitivity analysis GRANULO was partially verified with data from the field experiments. The model then served to evaluate the UV stability and the transmission rates in several simulations. Although further verification and validation of GRANULO would be desirable, this model is a first step in the quantitative approximation of the population dynamics of CpGV. The discussed results could render valuable information towards the optimisation of CpGV as control agent. Moreover, they can shed light on the mechanisms by which this bioinsecticide could establish itself in the field