Measuring Network Effects in Mobile Telecommunications Markets with Stated‐Preference Valuation Methods

This paper demonstrates how stated-preference methods can be applied to modeling consumers' preferences in the field of mobile telecommunications, and to measuring and the valuation of network effects. We illustrate this with a case study of mobile phone operators in Poland. We utilize the Choice Experiment method and present the respondents with hypothetical choices of mobile phone operators, while explicitly controlling for network effects in the form of other users in the same network. Based on the hypothetical choices consumers make we construct a conditional random parameters multinomial logit model to analyze their preferences. This approach allows us to calculate welfare effects associated with alternatives, as well as marginal rates of substitution (and hence implicit prices) of the attributes used to describe the choices, such as operator brand and distribution of family and friends between available mobile networks. The latter constitutes a network effect as consumer's utility is influenced by the number (or ratio) of members of his or her family, friends and other users subscribed to the same operator. Our results confirm the existence of a strong network effect, which is related to the size of the social network group a particular subscriber belongs to, rather than the absolute size of the mobile operator's customer base. We observe that there are two sources of this 'gross' network effect - pecuniary (arising from possible price discounts for on-net calls) and non-pecuniary, and demonstrate a way to disaggregate them. In addition, we find that brand perception and brand loyalty are important determinants of operator choice. Finally, through the application of a non-market valuation method we are able to calculate monetary values of the network effect and brand loyalty, and both turn out to be relatively high. The results might be of a particular interest to mobile phone operators and regulatory authorities - we find that the capacity for vigorous price competition between mobile operators is limited due to significant non-price barriers which mitigate subscribers' mobility in the market. We demonstrate a way to measure these effects in monetary terms based on modeling of consumer preferences. --Network effects,mobile telecommunications,brand valuation,stated preference methods,non-market valuation methods,choice experiment,multinomial conditional logit model,preference heterogeneity,random parameters model

Lead dependent tricuspid dysfunction: Analysis of the mechanism and management in patients referred for transvenous lead extraction

Background: Lead-dependent tricuspid dysfunction (LDTD) is one of important complicationsin patients with cardiac implantable electronic devices. However, this phenomenon isprobably underestimated because of an improper interpretation of its clinical symptoms. Theaim of this study was to identify LDTD mechanisms and management in patients referred fortransvenous lead extraction (TLE) due to lead-dependent complications.Methods: Data of 940 patients undergoing TLE in a single center from 2009 to 2011 wereassessed and 24 patients with LDTD were identifi ed. The general indications for TLE, pacingsystem types and lead dwell time in both study groups were comparatively analyzed. Theradiological and clinical effi cacy of TLE procedure was also assessed in both groups with precisionestimation of clinical status patients with LDTD (before and after TLE). Additionally,mechanisms, concomitant lead-dependent complications and degree (severity) of LDTD beforeand after the procedure were evaluated. Telephone follow-up of LDTD patients was performedat the mean time 1.5 years after TLE/replacement procedure.Results: The main indications for TLE in both groups were similar (apart from isolatedLDTD in 45.83% patients from group I). Patients with LDTD had more complex pacing systemswith more leads (2.04 in the LDTD group vs. 1.69 in the control group; p = 0.04). Therewere more unnecessary loops of lead in LDTD patients than in the control group (41.7% vs.5.24%; p = 0.001). There were no signifi cant differences in average time from implantationto extraction and the number of preceding procedures. Signifi cant tricuspid regurgitation(TR-grade III–IV) was found in 96% of LDTD patients, whereas stenosis with regurgitationin 4%. The 10% frequency of severe TR (not lead dependent) in the control group patients wasobserved. The main mechanism of LDTD was abnormal leafl et coaptation caused by: loop ofthe lead (42%), septal leafl et pulled toward the interventricular septum (37%) or too intensivelead impingement of the leafl ets (21%). LDTD patients were treated with TLE and reimplantationof the lead to the right ventricle (87.5%) or to the cardiac vein (4.2%), or surgery procedure with epicardial lead placement following ineffective TLE (8.3%). The radiological and clinicaleffi cacy of TLE procedure was very high and comparable between the groups I and II (91.7%vs. 94.2%; p = 0.6 and 100% vs. 98.4%; p = 0.46, respectively). Repeated echocardiographyshowed reduced severity of tricuspid valve dysfunction in 62.5% of LDTD patients. The follow--up interview confi rmed clinical improvement in 75% of patients (further improvement aftercardiosurgery in 2 patients was observed).Conclusions: LDTD is a diagnostic and therapeutic challenge. The main reason for LDTDwas abnormal leafl et coaptation caused by lead loop presence, or propping, or impingementthe leafl ets by the lead. Probably, TLE with lead reimplantation is a safe and effective optionin LDTD management. An alternative option is TLE with omitted tricuspid valve reimplantation.Cardiac surgery with epicardial lead placement should be reserved for patients withineffective previous procedures

Krakowskie Studia Międzynarodowe nr 1 (XV), 2018 (Współpraca Chińskiej Republiki Ludowej z Federacją Rosyjską a nowy wymiar stosunków międzynarodowych w XXI wieku. Część 1 Znaczenie współpracy Chin i Rosji dla kształtowania nowego porządku międzynarodowego)

ZE WSTĘPU: "Celem kolejnego tomu „Krakowskich Studiów Międzynarodowych” (KSM) jest dążenie do przedstawienia głównych przesłanek i następstw zacieśnienia współpracy między Chińską Republiką Ludową (CHRL) a Federacją Rosyjską, określanych współcześnie zamiennie w publicystyce i pracach naukowych jako Chiny i Rosja. Zagadnienie powyższe zostało zaprojektowane w dwóch powiązanych ze sobą zakresach tematyczno-merytorycznych: 1) Współdziałanie Chin z Rosją w kształtowaniu nowego porządku międzynarodowego – cześć 1; 2) Chiny i Rosja wobec nowych wyzwań bezpieczeństwa i współpracy międzynarodowej – część 2. Autorzy obu tomów złożyli swoje artykuły w Oficynie Wydawniczej Krakowskiej Akademii im. Andrzeja Frycza Modrzewskiego (KAAFM) zgodnie z ustalonym trybem redakcyjnym na przełomie kwietnia i maja 2018 r. Jednak przyspieszony bieg ważnych wydarzeń międzynarodowych (od maja po lipiec 2018 r.), związanych z podjętą problematyką badawczą części 1 i 2 KSM (2018), skłonił redaktora naukowego tomu do ich szerszego skomentowania w obu odrębnie przygotowanych częściach wprowadzenia.

Bimodal antagonism of PKA signalling by ARHGAP36

Protein kinase A is a key mediator of cAMP signalling downstream of G-protein-coupled receptors, a signalling pathway conserved in all eukaryotes. cAMP binding to the regulatory subunits (PKAR) relieves their inhibition of the catalytic subunits (PKAC). Here we report that ARHGAP36 combines two distinct inhibitory mechanisms to antagonise PKA signalling. First, it blocks PKAC activity via a pseudosubstrate motif, akin to the mechanism employed by the protein kinase inhibitor proteins. Second, it targets PKAC for rapid ubiquitin-mediated lysosomal degradation, a pathway usually reserved for transmembrane receptors. ARHGAP36 thus dampens the sensitivity of cells to cAMP. We show that PKA inhibition by ARHGAP36 promotes derepression of the Hedgehog signalling pathway, thereby providing a simple rationale for the upregulation of ARHGAP36 in medulloblastoma. Our work reveals a new layer of PKA regulation that may play an important role in development and disease

Manipulacja: pedagogiczno-społeczne aspekty. Cz. 1, Interdyscyplinarne aspekty manipulacji

Praca recenzowana / peer-reviewed pape

TERRORYZM EKSTREMISTÓW ISLAMSKICH

W pracy autor opisuje zjawisko, które w chwili obecnej jest jednym z najistotniejszych zagrożeń, zarówno w wymiarze narodowym, jak i międzynarodowym. Jest to zjawisko terroryzmu uwarunkowanego przekonaniami religijnymi i dość często niesłusznie nazywane terroryzmem islamskim. Właściwym określeniem, jakiego należałoby używać w tym kontekście jest terroryzm fundamentalistów, radykałów bądź też ekstremistów islamskich. To przymiotnikowe określenie terroryzmu islamskiego jest konieczne z oczywistego powodu. Nie wszyscy muzułmanie są terrorystami, a ci którzy nie są radykałami potępiają terroryzm w zgodzie z zasadą nie używania przemocy. Autor podejmuje także trudną kwestię definiowania pojęcia terroryzmu oraz źródeł, nurtów i rodzaj ów terroryzmu. W pracy podjęto także kwestie ogólne dotyczące analizy kultury bezpieczeństwa i interpretację a szczególnie jej pierwszego wymiaru dotyczącego zespołu podstawowych wartości, norm, i przekonań nazywanego filarem mentalno-duchowym. Ta warstwa kultury bezpieczeństwa w sposób istotny wpływa na sposób interpretowania wyzwań bądź zagrożeń organizujących zachowania jednostki

Die Rolle von Notch und Integrin-β1 in der Muskelentwicklung

Craniofacial muscles are small skeletal muscles involved in mastication, swallowing, vocalization and facial expression. In contrast to trunk and limb muscles, the majority of craniofacial muscles originate from head mesoderm. Different transcriptional mechanisms control the expression of the myogenic regulatory factors and therefore entry into the differentiation program in trunk and craniofacial muscle. Notch signaling controls trunk myogenesis, but its function in craniofacial muscle development has been little investigated. I show here that the progenitor cell pool in craniofacial muscle of Dll1LacZ/Ki mutant mice is depleted early and that this is largely rescued by an additional mutation of MyoD. My data show that suppression of MyoD is the major function of Notch in both, craniofacial and trunk myogenesis. However, other Notch functions differ. In particular, colonization of emerging satellite cells and Pax7 expression is differentially affected by Notch signaling in somite- and cranial mesoderm-derived muscle. Muscle fibers are multinucleated syncytia that arise by the fusion of mononucleated myoblasts, which allows generation, growth, and repair of muscle fibers. On a cellular level, the fusion is characterized by cell adhesion, alignment of myoblast membranes and membrane fusion. Previous work had indicated that Integrin-β1 is essential for fusion. ILK is an adaptor protein that is known to bind to the intracellular domain of Integrin-β1, and is thought to transmit integrin signals to the cytoskeleton. I tested here whether ILK is essential for myoblast fusion and directly compared Integrin-β1 and ILK phenotypes. I observed pronounced deficits in myoblast fusion in ILK mutant mice in vivo, but the phenotype was less severe than the one observed for Integrin-β1 mutants. My data show that ILK is in part an essential downstream component of Integrin-β1 signaling in myoblast fusion, and suggest that ILK transmits Integrin signals to the cytoskeleton.Kraniofaziale Muskeln sind kleine Skelettmuskeln des Kopfes, die für Kauen, Schlucken, Vokalisierung und Gesichtsmimik benötigt werden. Im Gegensatz zu den Muskeln des Rumpfes und der Extremitäten stammt die Mehrheit der kraniofazialen Muskeln vom Kopfmesoderm ab. Verschiedene Transkriptionsfaktoren kontrollieren die Expression der Muskelregulationsfaktoren und somit den Eintritt in das Differenzierungsprogramm in der Muskulatur des Rumpfes und Kopfes. Der Notch- Signalweg kontrolliert die Myogenese im Rumpf, aber seine Funktion in der Entwicklung der kraniofazialen Muskeln wurde bisher nur wenig Untersucht. Ich zeige hier, dass der pool von Vorläuferzellen in kraniofazialen Muskeln Dll1LacZ/Ki-mutanter Mäuse zu einem frühen Zeitpunkt aufgebraucht ist und dass dies durch eine zusätzliche Mutation von MyoD größtenteils gerettet werden kann. Meine Daten zeigen, dass die Unterdrückung von MyoD Aktivität die Hauptfunktion von Notch in der Myogenese der Kopf- und Rumpfmuskulatur ist. Jedoch unterscheiden sich andere Funktionen von Notch. Insbesondere unterscheiden sich Satellitenzellen, die von Somiten oder dem kranialen Mesoderm abstammen, in Bezug auf die Notch-abhängige Kolonisierung der sich bildenden Satellitenzellnische und die Expression von Pax7. Muskelfasern sind multinukleäre Synzytien, die aus der Fusion von mononukleären Myoblasten hervorgehen. Myoblastenfusion läuft während der Entstehung, dem Wachstum und der Reparatur von Muskelfasern ab. Charakteristisch für die Fusion ist eine Zelladhäsion zwischen Myoblasten, die anfangs zu einer parallelen Ausrichtung der Zellmembranen führt, die dann aufgelöst werden. Genetische Arbeiten haben gezeigt, dass Integrin-β1 ein wichtiges Molekül in der Myoblastenfusion bei Mäusen ist. ILK ist ein Adaptorprotein, das die intrazelluläre Domäne von Integrin-β1 bindet und das Integrin-Signale an das Zytoskelett vermittelt. Ich habe hier untersucht, ob ILK essentiell für die Fusion von Myoblasten ist und habe die Phänotypen von Integrin-β1 und ILK direkt miteinander verglichen. Ich beobachtete ausgeprägte Defizite in der Myoblastenfusion ILK-mutanter Mäuse in vivo, die aber weniger schwer ausgeprägt waren als die Defizite in Integrin-β1-Mutanten. Meine Daten zeigen, dass ILK zum Teil eine essentielle nachgeschaltete Komponente des Integrin-β1-Signalweges in der Myoblastenfusion ist und deuten darauf hin, dass ILK Integrin-Signale an das Zytoskelett vermittelt

FREEDOM OF MOVEMENT OF PEOPLE AND THE RIGHT TO RESIDENCE IN THE EU LAW. SELECTED ISSUES

The article is an attempt to analyse Directive 2004/38/EC o f 29 April 2004 on the right of citizens of the Union and their family members to move and reside freely within the territory of the Member States. This document constitutes a turning-point in the regulation of the principles of exercising a right which belongs to the most important human rights. The enforcement of the directive is expected to eliminate most of the legal doubts that have existed so far, and to standardise the manner of application of the rules in force regarding the freedom of movement of people and the right of residence in the European Union member states

FREEDOM OF MOVEMENT OF PEOPLE AND THE RIGHT TO RESIDENCE IN THE EU LAW. SELECTED ISSUES

The article is an attempt to analyse Directive 2004/38/EC o f 29 April 2004 on the right of citizens of the Union and their family members to move and reside freely within the territory of the Member States. This document constitutes a turning-point in the regulation of the principles of exercising a right which belongs to the most important human rights. The enforcement of the directive is expected to eliminate most of the legal doubts that have existed so far, and to standardise the manner of application of the rules in force regarding the freedom of movement of people and the right of residence in the European Union member states