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The H2 internal combustion engine (ICE) is a key technology for complete decarbonization of the transport sector. To match or exceed the power density of conventional combustion engines, H2 direct injection (DI) is essential. Therefore, new injector concepts that meet the requirements of a H2 operation have to be developed. The macroscopic free stream behavior of H2 released from an innovative fluidic oscillating nozzle is investigated and compared with that of a conventional multi-hole nozzle. This work consists of H2 flow measurements and injection tests in a constant volume chamber using the Schlieren method and is accompanied by a LES simulation. The results show that an oscillating H2 free stream has a higher penetration velocity than the individual jets of a multi-hole nozzle. This behavior can be used to inject H2 far into the combustion chamber in the vertical direction while the piston is still near bottom dead center. As soon as the oscillation of the H2 free stream starts, the spray angle increases and therefore H2 is also distributed in the horizontal direction. In this phase of the injection process, spray angles comparable to those of a multi-hole nozzle are achieved. This behavior has a positive effect on H2 homogenization, which is desirable for the combustion process.

In this article we show that the catalytic isomerization of isohexide sugar alcohols as well as their respective ethers can occur by a hydride‐based mechanism rather than a dehydrogenation/re‐hydrogenation. C−H bonds in α‐position to hydroxy and ether groups are activated using Ru/C as solid catalyst at temperatures as high as 160 °C and above. Hydrogen isotope exchange experiments proved that a full hydride exchange and isomerization is possible for isohexides but unexpectedly also for their methyl ethers. This is of great importance as it proves the co‐existence of the both mechanisms for reactions that were so far assumed to occur solely by a dehydrogenation/re‐hydrogenation. Hence, this co‐existence should be taken into account for kinetic investigations of such reaction systems especially in the conversion of biomass‐based chemicals under hydrogenation conditions.

ChemCatChem (2020). doi:10.1002/cctc.202000972, Published by WILEY-VCH Verlag, Weinheim

PURPOSE The adoption of a sentinel lymph node (SLN) algorithm and the presence of high bilateral detection rates have been associated with increased accuracy of SLN mapping in cervical and endometrial cancer patients. In this context, the significance of the number of SLNs removed has not yet been investigated. The aim of this study was to evaluate (a) whether or not a higher SLN removal count is associated with a reduced false-negative rate and (b) which clinical factors correlate with the number of SLNs removed. METHODS Patients with cervical or endometrial cancer who underwent SLN mapping with bilateral SLN detection followed by lymphadenectomy were evaluated retrospectively. On the basis of the mean number of the SLNs removed, the patients were divided in two groups: Group 1 included patients with up to 3 SLNs removed and Group 2 included patients with more than 3 SLNs removed. Factors predicting a higher SLN count were evaluated using univariate and multivariate analysis. RESULTS Eighty-four patients met the inclusion criteria. The two groups consisted of 42 patients each and differed only by the median SLN count. Two endometrial cancer patients in Group 1 had false-negative pelvic SLNs and isolated para-aortic metastases; no false-negative SLNs were recorded in Group 2 (p = n.s.). The results of multivariate analysis indicted that the number of SLNs removed was influenced only in cases where the operating surgeon had performed more than 20 laparoscopic ICG SLN mappings. CONCLUSIONS A higher SLN count does not seem to increase the accuracy of SLN mapping in cervical and endometrial cancer patients.

BACKGROUND In patients with a diagnosis of occult cervical cancer made on a hysterectomy specimen after surgery for a benign indication, lymph node assessment is crucial to determine treatment. We aimed to compare sentinel lymph node (SLN) mapping between patients with postoperative diagnosis of occult cervical carcinoma and patients with cervical cancer and uterus in situ. METHODS A retrospective analysis of cervical cancer patients International Federation of Gynecology and Obstetrics (FIGO) stage IA-IIA disease undergoing laparoscopic SLN mapping was performed. Patients were divided into two groups: those with a diagnosis of occult cervical cancer made on a hysterectomy specimen (group 1) and those with a diagnosis of cervical cancer and uterus in situ (group 2). Tracers used for SLN mapping included technetium-99m ((99m)Tc), blue dye, and indocyanine green. After detection and excision, the SLN was sent for frozen section analysis, and the planned surgical procedure was aborted in case of metastatic disease in favor of a chemoradiotherapeutic treatment. RESULTS Groups 1 and 2 included 9 and 62 patients, respectively. Clinicopathologic characteristics were similar among the two groups. Overall and bilateral detection rates were 66.6 and 33.3 and 95.1 and 87 % in groups 1 and 2, respectively (p