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Background: Due to centralization and super-specialization in medicine, hospital mergers are increasingly common. Their effect on postoperative outcomes in highly specialized surgical departments is unclear. As quality metrics often worsen after major organizational changes, preservation of quality of care during an hospital merge is of the utmost importance. Objective: To evaluate the effect of a merger of two Dutch university hospitals on quality of surgical care, volume, and timeliness of care. Methods: The upper gastro-intestinal and hepato-biliary-pancreatic sections merged on the 27th of January 2020 and the 31th of May 2021 respectively. Outcomes of all adult surgical patients were compared six months before and six months after the merger. Short-term quality metrics, volume, and timeliness of care were assessed. Results: Overall, a cohort of 631 patients were included of whom 195 were upper gastro-intestinal (97 prior to the merger, 98 after the merger) and 436 (223 prior to the merger, 213 after) hepato-biliary-pancreatic patients. There were no differences in mortality, readmission, number and severity of complications, volume, and timeliness of care six months post-merger as compared to before merger. Conclusion: This study shows that a hospital merger of two university hospitals can be performed without jeopardizing patient safety and while benefitting from centralization of highly specialized care and enhancement of medical research. Key message: This study investigated the impact of a merger of two Dutch university hospitals on quality of care, timeliness of care, and volume. It showed no deterioration in the evaluated short-term quality metrics, volume or timeliness for upper GI and HPB surgery, suggesting that a hospital merger of two university hospitals can be performed safely, while benefitting from centralization of highly specialized care and enhancement of medical research.

Background: Recurrence is frequently observed after esophageal cancer surgery, with dismal post-recurrence survival. Neoadjuvant chemoradiotherapy followed by esophagectomy is the gold standard for resectable esophageal tumors in the Netherlands. This study investigated the recurrence patterns and survival after multimodal therapy. Methods: This retrospective cohort study included patients with recurrent disease after neoadjuvant chemoradiotherapy followed by esophagectomy for an esophageal adenocarcinoma in the Amsterdam UMC between 01 and 01–2010 and 31-12-2018. Post-recurrence treatment and survival of patients were investigated and grouped by recurrence site (loco-regional, distant, or combined loco-regional and distant). Results: In total, 278 of 618 patients (45.0%) developed recurrent disease after a median of 49 weeks. Thirty-one patients had loco-regional (11.2%), 145 distant (52.2%), and 101 combined loco-regional and distant recurrences (36.3%). Post-recurrence survival was superior for patients with loco-regional recurrences (33 weeks, 95%CI 7.3–58.7) compared to distant (12 weeks, 95%CI 6.9–17.1) or combined loco-regional and distant recurrent disease (18 weeks, 95%CI 9.3–26.7). Patients with loco-regional recurrences treated with curative intent had the longest survival (87 weeks, 95%CI 6.9–167.4). Conclusion: Recurrent disease after potentially curative treatment for esophageal cancer was most frequently located distantly, with dismal prognosis. A subgroup of patients with loco-regional recurrence was treated with curative intent and had prolonged survival. These patients may benefit from intensive surveillance protocols, and more research is needed to identify these patients.

We report the fabrication of a microreactor with embedded internal reflection element (IRE) and herringbone (HB) micromixer. The microreactor can be used as a powerful tool for monitoring in-situ chemical reactions when combined with attenuated total internal reflection (ATR) infrared (IR) spectroscopy. In this work, a H2O/D2O model reaction was monitored as a proof of concept and the HOD product formation was spatially tracked. In addition to this, a mixing efficiency of 99% at 25 cycles was also calculated for the microreactor.

Gold nanoparticles (AuNPs) were the basis for the earliest research in the field of surface enhanced Raman scattering (SERS). Coupling of their surface plasmon resonances creates hot-spots of high electromagnetic intensities found to be very useful for sensing applications. However, chemically synthesized AuNPs in suspension are usually polydisperse and when arranged on a SERS substrate, lack periodic spatial organization. This leads to large variations in the enhancement factor (EF) which is detrimental to the sensing capabilities of the SERS substrate. Here, we showcase reproducible fabrication of an array of spherical AuNPs at the apices of shell isolated silicon nanocones with a homogeneous EF for SERS. The AuNPs are produced through discrete rotation glancing angle deposition of Au on shell isolated silicon nanocones (SI-SiNC) with square lattice periodicity and 250 nm pitch. By tuning the substrate tilt angle, substrate rotation angle and deposition thickness, the location and the size of the AuNPs formed can be controlled. Using this method, we successfully fabricated 60 nm AuNPs positioned at the apices of the nanocone array. Finite-Difference Time-Domain (FDTD) simulations were performed to visualize the electric field enhancement and verify conditions such as tip radius and oxide shell thickness to optimize the same. The EF was then experimentally calculated by performing SERS measurements on benzenethiol (BT) functionalized AuNPs at 400 unique points over the SI-SiNC substrate and compared to measurements of pure BT solution. A homogeneous substrate EF of (2.05 ± 0.05) ∙107 (99% confidence interval) at par with literature was calculated for the C-S in-plane deformation mode, δCS, of the BT molecule excited at 1077 cm-1. Our work highlights the advantages of nanofabrication for homogeneous SERS EF substrates.

Sustained casing pressure (SCP), surface casing vent flow (SCVF) and other expressions of annular fluid migration are widely encountered zonal isolation issues. Conventional solutions for SCP/SCVF include perforate and squeeze cementing, or section milling and recementing. Regrettably, the former approach shows only limited success rates, while the latter involves time and cost intensive operations that require a drilling rig. We will show that localized casing expansion (LCE) technologies offer promising alternatives, enabling rigless remediation of annular fluid migration. The LCE concept involves imposing permanent deformation on the casing pipe to locally enlarge its diameter. The associated annular volume reduction causes closure of defects such as micro-annuli and cement fractures, plus potentially even larger voids, and results in an overall densification of the cement microstructure. The Shell-developed Local Expander tool is e-line deployable and imposes the required casing deformation in a mechanical, fully controlled manner. Tailored-shaped energetic charges offer valuable supplementary means for achieving expansion. We will demonstrate the sealing effectiveness of LCE in both laboratory experiments and field trials, describe how the radial deformation impacts the casing and cement, and generally discuss the current state of knowledge, capabilities and limitations of LCE with respect to SCP/SCVF remediation.

TNF alpha signaling in the vascular endothelium elicits multiple inflammatory responses that drive vascular destabilization and leakage. Bioactive lipids are main drivers of these processes. In vitro mechanistic studies of bioactive lipids have been largely based on two-dimensional endothelial cell cultures that, due to lack of laminar flow and the growth of the cells on noncompliant stiff substrates, often display a pro-inflammatory phenotype. This complicates the assessment of inflammatory processes. Three-dimensional microvessels-on-a-chip models provide a unique opportunity to generate endothelial microvessels in a more physiological environment. Using an optimized targeted liquid chromatography-tandem mass spectrometry measurements of a panel of pro- and anti-inflammatory bioactive lipids, we measure the profile changes upon administration of TNF alpha. We demonstrate that bioactive lipid profiles can be readily detected from three-dimensional microvessels-on-a-chip and display a more dynamic, less inflammatory response to TNF alpha, that resembles more the human situation, compared to classical two-dimensional endothelial cell cultures.

Metal-halide perovskite nanocrystals show promise as the future active material in photovoltaics, lighting, and other optoelectronic applications. The appeal of these materials is largely due to the robustness of the optoelectronic properties to structural defects. The photoluminescence quantum yield (PLQY) of most types of perovskite nanocrystals is nevertheless below unity, evidencing the existence of nonradiative charge-carrier decay channels. In this work, we experimentally elucidate the nonradiative pathways in CsPbBr3 nanoplatelets, before and after chemical treatment with PbBr2 that improves the PLQY. A combination of picosecond streak camera and nanosecond time-correlated single-photon counting measurements is used to probe the excited-state dynamics over 6 orders of magnitude in time. We find that up to 40% of the nanoplatelets from a synthesis batch are entirely nonfluorescent and cannot be turned fluorescent through chemical treatment. The other nanoplatelets show fluorescence, but charge-carrier trapping leads to losses that are prevented by chemical treatment. Interestingly, even without chemical treatment, some losses due to trapping are mitigated because trapped carriers spontaneously detrap on nanosecond-to-microsecond timescales. Our analysis shows that multiple nonradiative pathways are active in perovskite nanoplatelets, which are affected differently by chemical treatment with PbBr2. More generally, our work highlights that in-depth studies using a combination of techniques are necessary to understand nonradiative pathways in fluorescent nanocrystals. Such understanding is essential to optimize synthesis and treatment procedures.

ZnS shelling of I-III-VI2 nanocrystals (NCs) invariably leads to blue-shifts in both the absorption and photoluminescence spectra. These observations imply that the outcome of ZnS shelling reactions on I-III-VI2 colloidal NCs results from a complex interplay between several processes taking place in solution, at the surface of, and within the seed NC. However, a fundamental understanding of the factors determining the balance between these different processes is still lacking. In this work, we address this need by investigating the impact of precursor reactivity, reaction temperature, and surface chemistry (due to the washing procedure) on the outcome of ZnS shelling reactions on CuInS2 NCs using a seeded growth approach. We demonstrate that low reaction temperatures (150 °C) favor etching, cation exchange, and alloying regardless of the precursors used. Heteroepitaxial shell overgrowth becomes the dominant process only if reactive S- and Zn-precursors (S-ODE/OLAM and ZnI2) and high reaction temperatures (210 °C) are used, although a certain degree of heterointerfacial alloying still occurs. Remarkably, the presence of residual acetate at the surface of CIS seed NCs washed with ethanol is shown to facilitate heteroepitaxial shell overgrowth, yielding for the first time CIS/ZnS core/shell NCs displaying red-shifted absorption spectra, in agreement with the spectral shifts expected for a type-I band alignment. The insights provided by this work pave the way toward the design of improved synthesis strategies to CIS/ZnS core/shell and alloy NCs with tailored elemental distribution profiles, allowing precise tuning of the optoelectronic properties of the resulting materials.

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Despite a surge of studies examining the role of social capital in the entrepreneurial process, no quantitative assessments exist of the empirical evidence to date. To resolve seemingly conflicting results, we conducted a meta-analysis of the link between entrepreneurs' personal networks and small firm performance and identify new moderators affecting this relationship. Analyses of 61 independent samples indicated that the social capital-performance link was positive and significant (r

Semiconductor materials are commonplace in everyday life and most people could not live without them. Recently, colloidal semiconductor nanocrystals have gained a lot of interest, due to the possibility to precisely tune their optoelectronic properties by tuning the size and shape of the nanocrystals. Nowadays, such colloidal semiconductor nanocrystals show potential use in applications such as television screens, solar cells and light-emitting diodes (LEDs). However, the integration of semiconductor nanocrystals into devices is severely hindered by toxicity issues concerning the use of heavy metals such as Cd and Pb. Copper chalcogenide nanomaterials offer an interesting alternative, since they have shown to possess similar (e.g. photoluminescence), or novel (e.g. plasmonics), properties and are comprised of less toxic and more abundant elements such as Cu, Zn and Sn. Although a lot of research has been performed to obtain the same level of mastery over the synthesis of Cu-chalcogenide nanocrystals, as is currently available for Cd- and Pb-chalcogenide nanocrystals, and hence precisely tune the optoelectronic properties of colloidal Cu chalcogenide nanomaterials, there is still room for improvement. In this thesis, synthetic methodologies are discussed, that were developed to gain control over the synthesis and the optoelectronic properties of colloidal Cu-chalcogenide nanomaterials, with special emphasis on alternative synthesis approaches. This thesis shows that by controlling the size, shape, composition and interactions of colloidal semiconductor nanocrystals, tailored materials can be prepared with high precision, which should possibly lead to unprecedented properties that will impact on a number of applications.

The direct synthesis of heteronanocrystals (HNCs) combining different ternary semiconductors is challenging and has not yet been successful. Here, we report a sequential topotactic cation exchange (CE) pathway that yields CuInSe2/CuInS2 dot core/rod shell nanorods with near-infrared luminescence. In our approach, the Cu+ extraction rate is coupled to the In3+ incorporation rate by the use of a stoichiometric trioctylphosphine-InCl3 complex, which fulfills the roles of both In-source and Cu-extracting agent. In this way, Cu+ ions can be extracted by trioctylphosphine ligands only when the In–P bond is broken. This results in readily available In3+ ions at the same surface site from which the Cu+ is extracted, making the process a direct place exchange reaction and shifting the overall energy balance in favor of the CE. Consequently, controlled cation exchange can occur even in large and anisotropic heterostructured nanocrystals with preservation of the size, shape, and heterostructuring of the template NCs into the product NCs. The cation exchange is self-limited, stopping when the ternary core/shell CuInSe2/CuInS2 composition is reached. The method is very versatile, successfully yielding a variety of luminescent CuInX2 (X = S, Se, and Te) quantum dots, nanorods, and HNCs, by using Cd-chalcogenide NCs and HNCs as templates. The approach reported here thus opens up routes toward materials with unprecedented properties, which would otherwise remain inaccessible.

The direct synthesis of heteronanocrystals (HNCs) combining different ternary semiconductors is challenging and has not yet been successful. Here, we report a sequential topotactic cation exchange (CE) pathway that yields CuInSe2/CuInS2 dot core/rod shell nanorods with near-infrared luminescence. In our approach, the Cu(+) extraction rate is coupled to the In(3+) incorporation rate by the use of a stoichiometric trioctylphosphine-InCl3 complex, which fulfills the roles of both In-source and Cu-extracting agent. In this way, Cu(+) ions can be extracted by trioctylphosphine ligands only when the In-P bond is broken. This results in readily available In(3+) ions at the same surface site from which the Cu(+) is extracted, making the process a direct place exchange reaction and shifting the overall energy balance in favor of the CE. Consequently, controlled cation exchange can occur even in large and anisotropic heterostructured nanocrystals with preservation of the size, shape, and heterostructuring of the template NCs into the product NCs. The cation exchange is self-limited, stopping when the ternary core/shell CuInSe2/CuInS2 composition is reached. The method is very versatile, successfully yielding a variety of luminescent CuInX2 (X = S, Se, and Te) quantum dots, nanorods, and HNCs, by using Cd-chalcogenide NCs and HNCs as templates. The approach reported here thus opens up routes toward materials with unprecedented properties, which would otherwise remain inaccessible.

Over the past few years, colloidal copper chalcogenide nanocrystals (NCs) have emerged as promising alternatives to conventional Cd and Pb chalcogenide NCs. Owing to their wide size, shape, and composition tunability, Cu chalcogenide NCs hold great promise for several applications, such as photovoltaics, lighting and displays, and biomedical imaging. They also offer characteristics that are unparalleled by Cd and Pb chalcogenide NCs, such as plasmonic properties. Moreover, colloidal Cu chalcogenide NCs have low toxicity, potentially lower costs, and excellent colloidal stability. This makes them attractive materials for the large-scale deployment of inexpensive, sustainable, and environmentally benign solution-processed devices. Nevertheless, the synthesis of colloidal Cu chalcogenide NCs, especially that of ternary and quaternary compositions, has yet to reach the same level of mastery as that available for the prototypical Cd chalcogenide based NCs. This review provides a concise overview of this rapidly advancing field, sketching the state of the art and highlighting the key challenges. We discuss recent developments in the synthesis of size-, shape-, and composition-controlled NCs of Cu chalcogenides, with emphasis in strategies to circumvent the limitations arising from the need to precisely balance the reactivities of multiple precursors in synthesizing ternary and quaternary compositions. In this respect, we show that topotactic cation-exchange reactions are a promising alternative route to complex multinary Cu chalcogenide NCs and hetero-NCs, which are not attainable by conventional routes. The properties and potential applications of Cu chalcogenide NCs and hetero-NCs are also addressed.

Aim The tunicate Molgula manhattensis has a disjunct amphi-Atlantic distribution and a recent history of world-wide introductions. Its distribution could be the result of regional extinctions followed by post-glacial recolonization, or anthropogenic dispersal. To determine whether the North Atlantic distribution of M. manhattensis is natural or human-mediated, we analysed mtDNA cytochrome c oxidase subunit I (COI) sequence variation in individuals from cryptogenic and introduced ranges. Location North Atlantic Europe and America; Black Sea; San Francisco Bay; Osaka Bay. Methods Nuclear 18S rDNA sequences were used to resolve phylogenetic relationships and mtDNA COI sequences for phylogeographic analyses. Results Phylogenetic analyses confirmed that M. manhattensis and M. socialis, which are frequently confused, are distinct species. MtDNA haplotype diversity was nearly three times higher with deeper relationships among haplotypes on the North-east American coast than in Europe. Diversity declined from south to north in America but not in Europe. In areas of known introductions (Black Sea, Japan, San Francisco Bay), M. manhattensis showed variable levels of haplotype diversity. Medium-to-high-frequency haplotypes originating from the North-west Atlantic were present in two locations of known introductions, but not in Europe. Private haplotypes were found on both sides of the Atlantic and in introduced populations. The mismatch distribution for the North-east Atlantic coast indicates a recent expansion. Main conclusions Molgula manhattensis is native in North-east America. However, whether it was introduced or is native to Europe remains equivocal. Additional sampling might or might not reveal the presence of putative private European haplotypes in America. The low European diversity may be explained by low effective population size and a recent expansion, or by low propagule pressure of anthropogenic introduction. Absence of medium-to-high-frequency American haplotypes in Europe may be the result of exclusive transport from southern ports, or long-term residence. These arguments are ambiguous, and M. manhattensis remains cryptogenic in Europe.