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Combinatorial auctions are auctions in which bids can be submitted on sets of items, rather than just on individual items. These auctions are generally beneficial to both auctioneers and bidders, as they allow bidders to express their synergies for sets of items. In recent years, we have seen the advent of combinatorial auctions as well as the emergence of online market platforms with competing auctioneers. However, combinatorial auctions have largely been absent from these platforms. Our article provides an explanation for this absence by demonstrating that competition between auctioneers can reduce the attractiveness of offering combinatorial auctions. Specifically, we show that auctioneers can limit competitive pressure between themselves by allowing bids only on specific packages, where these packages differ between auctioneers. This results in market segmentation, which increases bidder competition, and consequently increases auctioneer revenues. These findings have implications for market design. In particular they imply that, for an online market platform having multiple sellers offering auctions to the same set of buyers, it might not be advantageous to offer combinatorial auctions as a design option to the competing sellers. We investigate whether revenue-maximizing auctioneers selling heterogeneous items will allow for combinatorial bidding in the presence of auctioneer competition. We compare the choice of auction format by two competing auctioneers with that of a single auctioneer. Bidders are heterogeneous in their demands, with some having synergies for items. We find that, even if a single auctioneer offers a combinatorial auction, competing auctioneers in a comparable setting will not. Instead, the competing auctioneers will segment the market by restricting allowable package bids in order to increase competition between bidders. This shows that it might not be advantageous for an online market platform to offer combinatorial auctions as a design option to competing auctioneers. History: This paper has been accepted for the Information Systems Research Special Section on Market Design and Analytics. Funding: Financial support from the Deutsche Forschungsgemeinschaft [Grants KI 1915/1-1 and OT 487/2-1] is gratefully acknowledged by T. Kittsteiner and M. Ott. Supplemental Material: The online appendix is available at https://doi.org/10.1287/isre.2021.1018. [ABSTRACT FROM AUTHOR]

Research suggests the relationship between time pressure and software quality to be more complex than presumed. While software developers can adjust their output to improve observed performance at the expense of software quality, the latter has been found to increase with time pressure in case of work-pace dependent incentives. An untested, but widely disseminated game-theoretical model seeks to resolve this contradiction and hypothesizes that high rates of time pressure avoid so-called 'shortcuts', which occur in the form of imperfections induced by developers to meet unrealistically tight deadlines. We conduct two laboratory experiments to empirically test this model for the first time. Our results corroborate the model with regard to its suggestion that shortcuts can be reduced if developers perceive unrealistic deadlines as ever-present. However, we also show that the actual critical probability of unrealistic deadlines–the point at which shortcut taking is drastically reduced–is above the theoretical one. Although final conclusions on the impact of time pressure on software quality remain to be drawn, our results suggest that–considering the contingencies of our study–time pressure helps in striving for quality in software projects. [ABSTRACT FROM AUTHOR]

Copyright of Journal for Sociology of Education & Socialization / Zeitschrift für Soziologie der Erziehung & Sozialisation is the property of Julius Beltz GmbH & Co. KG Beltz Juventa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal for Sociology of Education & Socialization / Zeitschrift für Soziologie der Erziehung & Sozialisation is the property of Julius Beltz GmbH & Co. KG Beltz Juventa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article deals with discourses of breastfeeding in routine paediatric check ups. The authors reconstruct how breastfeeding discourses are invoked during check ups and how breastfeeding norms can be established. It is shown that the divergent invocations of breastfeeding-discourses during check ups entail an unintended dynamic for check ups in practice. The face-to-face interaction within the institutional setting enforces specific position in relation to the breastfeeding discourses from all participants. [ABSTRACT FROM AUTHOR]

Gene-modified autologous hematopoietic stem cells (HSC) can provide ample clinical benefits to subjects suffering from X-linked chronic granulomatous disease (X-CGD), a rare inherited immunodeficiency characterized by recurrent, often life-threatening bacterial and fungal infections. Here we report on the molecular and cellular events observed in two young adults with X-CGD treated by gene therapy in 2004. After the initial resolution of bacterial and fungal infections, both subjects showed silencing of transgene expression due to methylation of the viral promoter, and myelodysplasia with monosomy 7 as a result of insertional activation of ecotropic viral integration site 1 (EVI1). One subject died from overwhelming sepsis 27 months after gene therapy, whereas a second subject underwent an allogeneic HSC transplantation. Our data show that forced overexpression of EVI1 in human cells disrupts normal centrosome duplication, linking EVI1 activation to the development of genomic instability, monosomy 7 and clonal progression toward myelodysplasia. [ABSTRACT FROM AUTHOR]

Gene transfer into hematopoietic stem cells has been used successfully for correcting lymphoid but not myeloid immunodeficiencies. Here we report on two adults who received gene therapy after nonmyeloablative bone marrow conditioning for the treatment of X-linked chronic granulomatous disease (X-CGD), a primary immunodeficiency caused by a defect in the oxidative antimicrobial activity of phagocytes resulting from mutations in gp91phox. We detected substantial gene transfer in both individuals' neutrophils that lead to a large number of functionally corrected phagocytes and notable clinical improvement. Large-scale retroviral integration site–distribution analysis showed activating insertions in MDS1-EVI1, PRDM16 or SETBP1 that had influenced regulation of long-term hematopoiesis by expanding gene-corrected myelopoiesis three- to four-fold in both individuals. Although insertional influences have probably reinforced the therapeutic efficacy in this trial, our results suggest that gene therapy in combination with bone marrow conditioning can be successfully used to treat inherited diseases affecting the myeloid compartment such as CGD. [ABSTRACT FROM AUTHOR]

Balancing power markets involve complex procurement auction mechanisms that are challenging both to design for auctioneers and to take part in for suppliers. Recent empirical work indicates that auction results from Austria and Germany do not match game‐theoretic predictions. Instead, suppliers adjust their bids to previous auctions results and do not reveal their actual costs within their bids. Therefore, this work focuses on bidding strategies of suppliers in the Austrian and German automatically‐activated Frequency Restoration Reserve auctions. First, the operating principle of the auctions is analyzed and the cost and profit structures are illustrated. Then, a theoretic approach for the derivation of optimal bidding strategies is presented, that allows the integration of price expectations based on historical market data. We validate our approach by a numerical application of the bidder's calculus. Finally, our theoretic results are confronted with Austrian and German auction outcomes. We find evidence that the identified bidding strategies are applied by the suppliers. This article is categorized under:Energy Systems Analysis > Economics and PolicyEnergy Infrastructure > Economics and PolicyEnergy Policy and Planning > Economics and PolicyConcentrating Solar Power > Economics and Policy Graphical representation of the bidder's calculus for different price scenarios in Austrian and German balancing power auctions. [ABSTRACT FROM AUTHOR]

The potential of gene therapy to cure inherited immunodeficiencies of the lymphoid compartment has been demonstrated in clinical trials of ADA-SCID and SCID-X1. To circumvent the missing in vivo selection advantage of the corrected cells in myeloid diseases the two patients in the recent successful chronic granulomatous disease (CGD) gene therapy trial received nonmyeloablative conditioning before transplantation of the corrected cells. 3 months after transplantation 20% and 10% of the granulocytes in the peripheral blood expressed gp91phox in patient 1 and patient 2, respectively. 5 to 9 months after therapy a 3 to 4 fold expansion of marked granulocytes in the peripheral blood appeared in both patients. The proportion of gene-corrected granulocytes in both patients was then stable until 524 days post transplantation in patient 1 and 343 days post transplantation in patient 2 which were the last time points analyzed. To characterize the clonality of the hematopoietic repopulation, the long term activity of individual clones and the distribution of the SFFV vector integration sites we analyzed peripheral blood leucocytes and sorted cells derived from different time points post transplantation with linear amplification mediated PCR (LAM-PCR) and accomplished high throughput sequencing and mapping of the insertion sites. For patient 1 we could identify 435 exactly mappable insertion sites. For patient 2 330 unique integrations could be assigned to the human genome. We detected 3 common integrations sites (CIS) in or near the loci of the zinc finger transcription factor homologous MDS1/EVI1 and PRDM16 in both patients and SETBP1 as a third CIS gene in patient 1. RNA analysis demonstrated an activating influence of the retroviral vector on the CIS genes in both patients. LAM-PCR analysis of CFU-GM and BFU-E derived colonies from both patients revealed that 1 to 4 integrations are present per cell and confirmed the increasing dominance of one MDS1/EVI1 clone in patient 1 seen in the peripheral blood LAM-PCR pattern. Our data show that the upregulation of specific human genes as a side effect of retroviral integration may lead to an unprecedented in vivo expansion of the concerned cell clones and have therefore great impact on future gene therapy strategies.Molecular Therapy (2006) 13, S279–S279; doi: 10.1016/j.ymthe.2006.08.803 [ABSTRACT FROM AUTHOR]