12 research outputs found
Task dependence of U.S. service offshoring patterns
This work offers new insights into the determinants of service offshoring
across countries and across service industries. Combining different data
sources over the 2006-2009 period, I find that certain country characteristics
affect offshoring costs for all services, while the effects of other
characteristics depend on the coordination requirements of the respective
service industry. The results from a zero-inflated Poisson pseudomaximum
likelihood estimation indicate that the effects of a membership in NAFTA, and
a common colonial past on service offshoring patterns depend on the task
content of the services. These results are robust to the control for
unobservable country-level heterogeneity. The quality of legal institutions, a
common legal origin, geographic distance, and time zone differences influence
offshoring patterns identically across all service industries
Aufgaben-basierte Analyse von Dienstleistungsoffshoring aus den Vereinigten Staaten
This dissertation consists of three essays that empirically analyze different
aspects of a task-based approach to U.S. service offshoring. The first two
essays seek to broaden our understanding of the structure of offshoring costs.
The first essay focuses on the measurement of task-based offshoring
susceptibility. The second essay extends the empirical exploration to the
interplay of the task content and country-level trade determinants in shaping
offshoring patterns. The third essay analyzes the wage effects of service
offshoring by accounting for such a richer structure of offshoring costs. The
first challenge in providing new evidence on service offshoring from a trade-
in-tasks perspective stems from the lack of consensus on how to construct a
task-based offshoring susceptibility measure. The first essay (chapter 2)
fills this gap by employing techniques of factor and regression analyses to
assess and compare the three most relevant approaches that have been proposed
in previous works. I establish an offshoring susceptibility ranking of service
occupations for each index and find that the three indices lead to
significantly different representations of reality. Such a sharp disagreement
between the measures significantly limits the comparability of empirical
studies and suggests that different measures reflect different phenomena. To
select the most valid task-based measure of an occupation’s offshoring
susceptibility, I propose an objective criterion which assesses how well
different measures perform in capturing the variation in ac- tual offshoring
flows across occupations. The two essays that follow build upon these first
findings and investigate how such task-based offshoring susceptibility
interacts with traditional determinants of trade costs and benefits in shaping
the pattern of service offshoring and its distributional consequences. In the
second essay (chapter 3) I consider another gap in the literature and analyze
the way in which the task content of services interacts with traditional
country-level determinants of services trade in shaping offshoring costs. This
interaction has so far been treated as a black box. The task content
influences the costs that arise from the fragmentation of the production
process, regardless of whether this fragmentation takes place within or across
country borders. In the context of offshoring, this fragmentation can incur
extra costs because it occurs across international borders. I build on
previous empirical works and consider a broad set of country characteristics
that have been found to affect bi- lateral services trade flows. Unlike these
previous analyses, I focus on whether the effects of these country-level
variables differ systematically with the task content of the respective
service industry. The results of the zero-inflated Poisson pseudo-maximum
likelihood estimation suggest that the interaction between task
characteristics and country characteristics determines the effects of colonial
ties and of a NAFTA membership on offshoring patterns. A better quality of
legal institutions, a common legal origin, geographic distance, and time zone
differences influence offshoring patterns identically across all service
industries, regardless of their offshoring requirements. These findings shed
doubt on the prediction that the spread of information and communication
technologies is automatically leading to an increasingly flat world for the
trade flows of services. In the third essay (chapter 4), I estimate the impact
of service offshoring on the real wages of workers in the United States by
controlling for workers’ skill levels and the offshoring susceptibility of
different occupations. Tradition- ally, international trade economists have
seen the fortunes of workers as tied to their skill levels. The findings of
first task-based analyses indicate that these predictions need to be refined
and that, next to the workers’ skill levels, the task content of occupations
shapes the labor market effects of offshoring. If we consider the recent
evidence that certain occupations (tasks) are more suscepti- ble to offshoring
and that, especially in the short run, it is likely that there are frictions
to switching between occupations, we would expect the wage effects of service
offshoring to depend not only on the respective skill level but also on the
character of the tasks performed. My study differs from existing works in
significant ways. Most importantly, I focus on service industries rather than
manufacturing industries and I use wage data at the individual rather than at
the firm or industry level. The results from a fixed-effects Mincerian wage
regression indicate that, within skill groups, the impact of service
offshoring on real wages depends on the task content of the respective
occupation. Medium- skilled and high-skilled workers employed in the least
offshorable occupations experience real wage increases, whereas medium-skilled
and high-skilled workers in the most offshorable occupations experience real
wage declines. These findings raise several questions with respect to the
optimal design of education policies. Several questions deserve more attention
in future works. For instance, so far, very little is known about the
complementarities of different tasks within an occupation. With the increasing
sensitivity for the necessity of task-based data, research on such within-
occupation task complementarities will likely become an active area of
research.Die vorliegende kumulative Dissertationsschrift setzt sich aus drei
Einzelbeiträgen zusammen. Der gemeinsame Forschungsschwerpunkt ist die
aufgaben-basierte Analyse von Dienstleistungsoffshoring aus den Vereinigten
Staaten - der sogenannte “trade-in-tasks” Ansatz. Die USA stellen eine
besonders relevante Fallstudie dar, da Dienstleistungen, insbesondere solche,
die von Unternehmen nachgefragt werden, eine besonders herausragende Rolle in
der US-Wirtschaft einnehmen. Die vorliegende Arbeit gliedert sich wie folgt.
Die Einleitung erläutert den möglichen Erkenntnisgewinn eines aufgaben-
basierten Ansatzes (Kapitel 1). Insbesondere die BerĂĽcksichtigung von
Offshoringkosten, die entsprechend des Aufgabengehalts ĂĽber verschiedene
Dienstleistungen variieren, kann bisherige Handelstheorien beträchtlich
differenzieren. Davon ausgehend leitet sich die Notwendigkeit neuer
empirischer ĂśberprĂĽfungen ab. Der erste Beitrag (Kapitel 2) Measuring task
content and offshorability liefert eine notwendige Voraussetzung fĂĽr eine
solche aufgaben-basierte Analyse. Anhand eines empirischen Kriteriums wird die
GĂĽltigkeit verschiedener existierender aufgaben-basierter MaĂźe beurteilt,
welche darauf abzielen, Dienstleistungen bezĂĽglich ihrer Eignung ins Ausland
verlagert zu werden zu klassifizieren. Bislang existiert kein Konsens in der
trade-in-tasks Literatur, wie solche MaĂźe konstruiert werden sollten und
verschiedene Forscher haben unterschiedliche Ansätze verfolgt. Kapitel 2
analysiert die drei relevantesten Ansätze für die trade-in-tasks Literatur in
den Vereinigten Staaten (Blinder 2007; Moncarz et al. 2008; Crinò 2010). Ein
Vergleich der Klassifikationen macht deutlich, dass die unterschiedlichen MaĂźe
zu verschiedenen Ergebnissen fĂĽhren. Dies ist insbesondere deshalb
problematisch, weil die Autoren die selbe Terminologie verwenden. Um die
Vergleichbarkeit verschiedener Studien zu gewährleisten, bedarf es eines
objektiven Kriteriums, welches die GĂĽltigkeit der verschiedenen MaĂźe
beurteilen kann. Hierfür wird im vorliegenden Beitrag der Erklärungsanteil an
der Varianz von tatsächlichen Offshoringströmen vorgeschlagen. Die Ergebnisse
verschiedener Schätzungen zeigen, dass der Ansatz von Moncarz et al. (2008)
die höchste Erklärungskraft aufweist. Die darauffolgenden zwei Beiträge
berĂĽcksichtigen diese ersten Ergebnisse und untersuchen wie solch ein
aufgaben-basiertes MaĂź der Verlagerungseignung mit traditionellen
Determinanten von Handelskosten und -vorteilen interagiert. Insbesondere wird
analysiert, wie dieses Zusammenspiel die Handelsmuster und Verteilungseffekte
von Dienstleistungsoffshoring beeinflusst. Der zweite Beitrag (Kapitel 3)
Task-dependency of U.S. service offshoring patterns untersucht die Interaktion
zwischen dem Aufgabengehalt verschiedener Dienstleistungen und
Länderdeterminanten von Handelskosten und liefert damit neue Einsichten in die
Struktur von Offshoringkosten. Zahlreiche Arbeitsmarkt- und Handelsökonomen
haben argumentiert, dass fĂĽr Dienstleistungen entsprechend ihres
Aufgabengehalts unterschiedliche Offshoringkosten anfallen. Ich kombiniere
diesen aufgaben-basierten Ansatz mit der Generalisierung und Erweiterung der
Quellen komparativer Kostenvorteile, um neue Erkentnisse ĂĽber die
Determinanten tatsächlicher Offshoringmuster zu gewinnen. Insbesondere teste
ich die Hypothese, ob der Aufgabengehalt die notwendigen Anforderungen fĂĽr
eine Verlagerung ins Ausland beeinflusst und ob das Zusammenspiel zwischen
diesen Anforderungen und bestimmten Ländercharakteristika Offshoringkosten
beeinflusst. Durch die Kombination verschiedener Datenquellen fĂĽr den Zeitraum
2006 bis 2009 zeigt die Analyse, dass bestimmte Ländercharakteristika
Offshoringkosten fĂĽr alle Dienstleistungen beeinflussen, wohingegen die
Effekte anderer Charakteristika von den Offshoringanforderungen der
entsprechen- den Dienstleistungsindustrien abhängen. Die Effekte einer
Mitgliedschaft im Nordamerikanischen Freihandelsabkommen (NAFTA) und
gemeinsamer kolonialer Beziehungen auf Offshoringmuster hängen vom
Aufgabengehalt der ausgelagerten Dienstleistung ab. Im Gegensatz dazu
beeinflussen die Qualität legaler Institutionen, gemeinsame juristische
Ursprünge, geographische Distanz und Zeitzonendifferenzen zwischen Ländern
Offshoringmuster unabhängig vom Aufgabengehalt identisch. Der dritte Beitrag
(Kapitel 4) Wage effects of U.S. service offshoring analysiert den Einfluss
von Dienstleistungsoffshoring auf die Reallöhne von Arbeitern in den
Vereinigten Staaten. Hierbei wird sowohl fĂĽr das Bildungsniveau der Arbeiter
als auch fĂĽr die aufgaben-basierte Verlagerungseignung verschiedener
Dienstleistungen kontrolliert. Durch dieses Vorgehen teste ich die Hypothese,
ob sich die Lohneffekte von Dienstleistungsoffshoring auch entsprechend des
Aufgabengehalts der jeweiligen Dienstleistung unterscheiden. Methodisch passe
ich einen Algorithmus an, der Individuen in verschiedenen Datenerhebungen des
Current Population Surveys identifiziert, so dass die Zeitdimension dieses
Datensatzes genutzt werden kann. Dadurch bin ich in der Lage fĂĽr
unbeobachtbare individuelle Heterogenität zu kontrollieren. Die Ergebnisse
einer fixed-effects Mincer Lohnregression bestätigen die getestete Hypothese.
Reallöhne von mittel- und hoch-ausgebildeten Arbeitern fallen in solchen
Dienstleistungen, welche die stärkste Verlagerungseignung aufweisen,
wohingegen sie fĂĽr mittel- und hoch- ausgebildete Arbeiter in den am wenigsten
verlagerungsgeeigneten Aufgaben steigen. Diese Ergebnisse bestätigen
Dienstleistungsoffshoring als eine Determinante gestiegener residualer
Lohnungleichheiten. Insgesamt vertieft die vorliegende Dissertation das
Verständnis einer relativ neuen Tendenz des internationalen Handels, dem
Dienstleistungsoffshoring, und liefert neue Einsichten fĂĽr die trade-in-tasks
Literatur. Es bedarf einer zunehmend vereinheitlichten Anwendung der
SchlĂĽsselkonzepte der trade-in-tasks Literatur sowie der Erhebung speziell
angepasster Datensätze, damit die trade-in-tasks Literatur in der Zukunft ein
dynamisches Forschungsfeld bleibt
Macrophages, Low-Grade Inflammation, Insulin Resistance and Hyperinsulinemia: A Mutual Ambiguous Relationship in the Development of Metabolic Diseases
Metabolic derangement with poor glycemic control accompanying overweight and obesity is associated with chronic low-grade inflammation and hyperinsulinemia. Macrophages, which present a very heterogeneous population of cells, play a key role in the maintenance of normal tissue homeostasis, but functional alterations in the resident macrophage pool as well as newly recruited monocyte-derived macrophages are important drivers in the development of low-grade inflammation. While metabolic dysfunction, insulin resistance and tissue damage may trigger or advance pro-inflammatory responses in macrophages, the inflammation itself contributes to the development of insulin resistance and the resulting hyperinsulinemia. Macrophages express insulin receptors whose downstream signaling networks share a number of knots with the signaling pathways of pattern recognition and cytokine receptors, which shape macrophage polarity. The shared knots allow insulin to enhance or attenuate both pro-inflammatory and anti-inflammatory macrophage responses. This supposedly physiological function may be impaired by hyperinsulinemia or insulin resistance in macrophages. This review discusses the mutual ambiguous relationship of low-grade inflammation, insulin resistance, hyperinsulinemia and the insulin-dependent modulation of macrophage activity with a focus on adipose tissue and liver
Enhanced Palmitate-Induced Interleukin-8 Formation in Human Macrophages by Insulin or Prostaglandin E2
Macrophages in pathologically expanded dysfunctional white adipose tissue are exposed to a mix of potential modulators of inflammatory response, including fatty acids released from insulin-resistant adipocytes, increased levels of insulin produced to compensate insulin resistance, and prostaglandin E2 (PGE2) released from activated macrophages. The current study addressed the question of how palmitate might interact with insulin or PGE2 to induce the formation of the chemotactic pro-inflammatory cytokine interleukin-8 (IL-8). Human THP-1 cells were differentiated into macrophages. In these macrophages, palmitate induced IL-8 formation. Insulin enhanced the induction of IL-8 formation by palmitate as well as the palmitate-dependent stimulation of PGE2 synthesis. PGE2 in turn elicited IL-8 formation on its own and enhanced the induction of IL-8 release by palmitate, most likely by activating the EP4 receptor. Since IL-8 causes insulin resistance and fosters inflammation, the increase in palmitate-induced IL-8 formation that is caused by hyperinsulinemia and locally produced PGE2 in chronically inflamed adipose tissue might favor disease progression in a vicious feed-forward cycle
The handling of SARS-CoV-2 associated deaths - infectivity of the body
The body of a deceased with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is considered infectious. In this study, we present the results of infectivity testing of the body and testing of mortuary staff for SARS-CoV-2. We performed real-time quantitative polymerase chain reaction (RT-qPCR) for SARS-CoV-2 on 33 decedents with ante mortem confirmed SARS-CoV-2 infection. Swabs of the body surface from five different body regions and from the body bag or coffin were examined. A subset of the swabs was brought into cell culture. In addition, screening of 25 Institute of Legal Medicine (ILM) personnel for ongoing or past SARS-CoV-2 infection was performed at two different time points during the pandemic. Swabs from all locations of the body surface and the body environment were negative in cases of negative post mortem nasopharyngeal testing (n=9). When the post mortem nasopharyngeal swab tested positive (n=24), between 0 and 5 of the body surface swabs were also positive, primarily the perioral region. In six of the cases, the body bag also yielded a positive result. The longest postmortem interval with positive SARS-CoV-2 RT-qPCR at the body surface was nine days. In no case viable SARS-CoV-2 was found on the skin of the bodies or the body bags. One employee (autopsy technician) had possible occupational infection with SARS-CoV-2; all other employees were tested negative for SARS-CoV-2 RNA or antibody twice. Our data indicate that with adequate management of general safety precautions, transmission of SARS-CoV-2 through autopsies and handling of bodies is unlikely
Hepatic Vasculopathy and Regenerative Responses of the Liver in Fatal Cases of COVID-19
Kaltschmidt B, Fitzek ADE, Schaedler J, et al. Hepatic Vasculopathy and Regenerative Responses of the Liver in Fatal Cases of COVID-19. Clinical Gastroenterology and Hepatology. 2021;(19):1726-1729