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The new oxygen-bridged geminal Si/P Frustrated Lewis Pair (FLP) tBu2P-O-Si(C2F5)3 (2) is able to reversibly bind carbon dioxide at ambient temperature. We compared its reactivity towards benzil, but-3-en-2-one, nitriles and phenylacetylene to that of the Al/P FLP tBu2P-O-AlBis2 (Bis = -CH(SiMe3)2) (1). When reacted with benzil, both, 1 and 2, form the 1,2-addition product, but in the Si/P FLP 2, the second carbonyl function additionally binds to the silicon atom. With but-3-en-2-one 2 forms the 1,2-addition product, while 1 binds in 1,4-position. The reaction with acetonitrile yielded an unexpected etheneimine adduct for both systems, while only 1 reacted with tert-butylnitrile. With benzonitrile and acrylonitrile, 2 showed reversible addition to the C≡N bond and 1 forms a stable adduct with benzonitrile. Solely 1 shows reactivity towards phenylacetylene affording a mixture of the CH deprotonation adduct tBu2P(H)-O-AlBis2(CCPh) and the FLP-CºC adduct under ring formation. All compounds were charac-te-rized by multinuclear NMR spectroscopy, XRD and elemental analysis.

In this contribution, we report on the "free" [P(C

The new oxygen-bridged geminal Si/P Frustrated Lewis Pair (FLP) tBu2 P-O-Si(C2 F5 )3 (2) is able to reversibly bind carbon dioxide at ambient temperature. We compared its reactivity towards benzil, but-3-en-2-one, nitriles and phenylacetylene to that of the Al/P FLP tBu2 P-O-AlBis2 (Bis=-CH(SiMe3 )2 ) (1). When reacted with benzil, both, 1 and 2, form the 1,2-addition product, but in the Si/P FLP 2, the second carbonyl function additionally binds to the silicon atom. With but-3-en-2-one 2 forms the 1,2-addition product, while 1 binds in 1,4-position. The reaction with acetonitrile yielded an unexpected etheneimine adduct for both systems, while only 1 reacted with tert-butylnitrile. With benzonitrile and acrylonitrile, 2 showed reversible addition to the C=N bond and 1 forms a stable adduct with benzonitrile. Solely 1 shows reactivity towards phenylacetylene affording a mixture of the CH deprotonation adduct tBu2 P(H)-O-AlBis2 (CCPh) and the FLP -C=C 1,2-addition adduct under ring formation. All compounds were characterized by multinuclear NMR spectroscopy, XRD and elemental analysis. © 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.

This paper focuses on causes in information logistics that hinder an efficient and waste free information flow. Therefore, waste, problems and KAIZENs identified in 14 value stream analyses 4.0 from different industry applications are investigated by a root cause analysis. These analyzed problems are clustered based on the phase in the information flow where they occur and the kind of waste they lead to. For every obtained cluster a generalized flow barrier is defined. The results can be used to support the selection of digital technologies and help to design efficient information flows in the production context.

The growing demand for individualized products increases the amount of information processed in manufacturing. To machine individualized variants, individual information must be processed and an individualized CNC-program must be generated for each order. This results in performance losses in terms of throughput time, costs and quality. The redesign and automation of information processing offers high potential for improvement. This paper presents a procedure to map and design the processing and flow of information for the machining of individualized product components. The procedure covers information processing between the configuration and the machining of customer individual components.

Kurzfassung Das Wertstromdesign ist eine etablierte Methode zur Entwicklung des Soll-Zustands eines Wertstroms. Durch die Möglichkeiten der Digitalisierung und Industrie 4.0 ergeben sich neue Anforderungen an ein Wertstromdesign. Es müssen beispielsweise die informationstechnische Vernetzung von Elementen des Wertstroms und der zunehmende produktspezifische Informationstransport stärker berücksichtigt werden. Hier stoßen vorhandene Methoden an ihre Grenzen, da der Fokus auf der Gestaltung von Materialflüssen liegt oder Informationsflüsse nicht im notwendigen Umfang betrachtet werden [1, 2]. Die in diesem Beitrag vorgestellte Methode setzt an genau dieser Stelle an und zeigt ein systematisches und auf den Wertstrom ausgerichtetes Vorgehen, welches die Integration digitaler Technologien, die die Gestaltung von Informationstransporten sowie die Entwicklung eines schlanken Wertstroms gleichermaßen adressiert.

The value stream method (VSM) is a well accepted, widely used and holistic method for mapping, analyzing and designing value streams in order to reduce waste. However, the new, promising opportunities of digitization and Industry 4.0 to integrate information flows, lower lead times and improve flexibility or productivity in complex environments are not covered by VSM. While a large number of guidelines and maturity models for Industry 4.0 is available, no sound method with a step-by-step-guidance for designing value streams holistically exists to date. With the VSM 4.0, consisting of a previously published Value Stream Analysis 4.0 (VSA 4.0) and a Value Stream Design 4.0 (VSD 4.0), we close this gap. The easy understandable and meanwhile often validated VSM 4.0 method helps to see classical as well as information wastes and designs lean value streams in terms of material and especially information flows.

Lake Malawi is famous for the rapid speciation of cichlid fishes, but the potential diversification of its invertebrate fauna is poorly studied. Using two mitochondrial DNA sequence markers (partial ND1 and Cyt b genes), we investigated the population genetic structure of the only known species of freshwater crab inhabiting Lake Malawi (Potamonautes lirrangensis (Rathbun, 1904)). We detected little overall genetic differentiation among different sampling sites (pairwise ΦST-values = 0.00–0.13). Genetic differentiation between sampling sites was better explained by linear distances than by shoreline distances, suggesting that ‘sweepstake dispersal’ between western and eastern shores occurs. Moreover, several population genetic parameters (Tajima’s D, Fu’s FS, Fay and Wu’s H and mismatch distribution analysis) suggest a recent population expansion, and Bayesian skyline plot analysis confirmed a sudden increase of the effective population size between 70 and 30 ka. Genetic diversity decreased towards the southern, shallower part of the lake, suggesting a more recent colonization of the southern shores. This finding is in line with hypotheses on Lake Malawi’s paleogeography suggesting that the lake largely desiccated during Pleistocene East African megadroughts and re-expanded southwards only recently after ~ 70 ka.

We describe a fossil freshwater crab specimen from the Tatrot Formation, Siwalik Group, of Northern India. We assign this specimen on the basis of morphology of the anterolateral margin, which is comparable to the extant species Acanthopotamon martensi (Wood-Mason, 1875) in the Ganges valley. We re-interpret previously described claw fragments from the same formation that have been assigned to the gecarcinucid species Sartoriana spinigera (Wood-Mason, 1871). This casts doubt on previous approaches to calibrate a molecular clock for primary freshwater crabs that used these fossils as minimum age of Sartoriana spinigera. However, the present findings allow setting a confident lower age constraint for the appearance of A. martensi to get a more accurate estimate for nucleic acid substitution rates. The age of fossil Acanthopotamon martensi based on the magnetostratigraphy of the Tatrot Formation is ∼2.6 Ma (latest Pliocene).

As a result of increasing awareness towards the topic of climate change and CO2 emissions, the product-specific resource consumption and its CO2 footprint will have an impact on the customers' purchasing decisions in the future. At the same time, the advancing digitalization in industrial production networks enables new potentials for companies to increase energy and resource efficiency and to act flexibly in this respect. To create transparency and to optimize the production process with regard to that, a cross-location production network was set up at the Technische Universitat Darmstadt. A tool for Value Stream Resource Analysis (VaRA) was developed in order to record the input and output resources of the production steps and to determine their degree of digitalization. This provides the basis for the calculation of energy and resource indicators and, for example, the preparation of a Life Cycle Assessment (LCA) or Material Flow Cost Accounting (MFCA) based on the data of the individual process steps of the value stream. In addition, the tool helps to select suitable component marking strategies according to the process steps. As a result, the resource flows within a production network become more transparent and initial improvement potentials can be identified.

Alle Daten, die Nutzerinnen und Nutzer aus dem Internet abrufen, gehen durch die Hande ihres Internet Service Providers (ISP). Dieser wird in der Literatur haufig als vertrauenswurdig angenommen. In dieser Arbeit wird aus technischer und juristischer Sicht hinterfragt, ob dieses Vertrauen gerechtfertigt ist. Weiterhin werden Transparenztechniken vorgestellt, die den Nutzerinnen und Nutzern helfen konnen, ihr Recht auf informationelle Selbstbestimmung gegenuber dem ISP zu starken.

We describe a new species of Cylindrophis currently known only from Grabag, Purworejo Regency, Jawa Tengah Pro-vince (Central Java), Java, Indonesia. Cylindrophis subocularis sp. nov. can be distinguished from all congeners by the presence of a single, eponymous subocular scale between the 3suprd/supand 4supth/supor 4supth/supand 5supth/supsupralabial, preventing contact between the 4supth/supor 5supth/supsupralabial and the orbit, and by having the prefrontal in narrow contact with or separated from the orbit. We preface our description with a detailed account of the tangled taxonomic history of the similar and putatively wide-ranging species C. ruffus, which leads us to (1) remove the name Scytale scheuchzeri from the synonymy of C. ruffus, (2) list the taxon C. rufa var. javanica as species inquirenda, and (3) synonymize C. mirzae with C. ruffus. We provide additional evidence to confirm that the type locality of C. ruffus is Java. Cylindrophis subocularis sp. nov. is the second species of Asian pipesnake from Java.

A new species of the gekkonid lizard genus Cyrtodactylus Gray, 1827 is described from Klakah, Lumajang Regency, Jawa Timur Province, Java, Indonesia. Cyrtodactylus klakahensis sp. nov. can be distinguished from all other congeners by the presence of (1) a deep precloacal groove in males, (2) three rows of enlarged precloacofemoral scales, of which the third row bears 37-38 pores in males, (3) three or four rows of enlarged scales between the precloacofemoral scale rows and the cloaca, forming distinct chevrons, (4) raised and strongly keeled dorsal tubercles in 15-19 rows at midbody, (5) an indistinct lateral fold, (6) 17-20 subdigital lamellae under the 4supth/suptoe, and (7) subcaudal scales which are not transversely enlarged. Cyrtodactylus klakahensis sp. nov. is only the third bent-toed gecko species described from Java, indicating that the diversity of this genus on this island has been neglected in the past. Furthermore, we confirm that C. fumosus (Müller, 1895) is a species that possesses a precloacal groove in males and is most likely restricted to northern Sulawesi. That species is defined by a single female holotype (NMB-REPT 2662). Specimens in museum collections catalogued as C. fumosus from localities elsewhere are misidentified and likely represent undescribed species.

Cyrtodactylus marmoratus Gray, 1831, a species of bent-toed gecko exhibiting a precloacal groove in males, was described on the basis of specimens collected by Heinrich Kuhl and Johan Conrad van Hasselt in Java, Greater Sunda Islands, Indonesia. Kluge (1985) subsequently designated a lectotype for C . marmoratus from a series of these specimens (i.e., syntypes), now housed in the herpetological collection at Naturalis (formerly the Rijksmuseum van Natuurlijke Historie; RMNH), Leiden, the Netherlands. Our work at Naturalis shows that the type series of C . marmoratus at RMNH actually comprises two sets of specimens, and that examination of specimens from one set or the other by different authors, including Kluge (1985), is responsible for some confusion surrounding the type series of this species. As a consequence, we present relevant morphological data for all 14 specimens constituting the type series of C . marmoratus at RMNH for the first time. The type status of two specimens of C . marmoratus in the collection at the Museum National d’Histoire Naturelle, Paris, France, remains unresolved at present. Owing to the inconsistent naming and application of terms for some key characters (e.g., groove, sulcus, pit, hollow, depression) used in the diagnoses of Cyrtodactylus species, we here propose a set of novel and useful definitions that are supported by photographs. We also illustrate the sexually dimorphic expression of this character in C . marmoratus . Finally, we present a revised comparative table for the bent-toad geckos of the Sunda Islands and Sulawesi.

We describe a new species of Cylindrophis currently known only from Grabag, Purworejo Regency, Jawa Tengah Pro-vince (Central Java), Java, Indonesia. Cylindrophis subocularis sp. nov. can be distinguished from all congeners by the presence of a single, eponymous subocular scale between the 3rd and 4th or 4th and 5th supralabial, preventing contact between the 4th or 5th supralabial and the orbit, and by having the prefrontal in narrow contact with or separated from the orbit. We preface our description with a detailed account of the tangled taxonomic history of the similar and putatively wide-ranging species C. ruffus, which leads us to (1) remove the name Scytale scheuchzeri from the synonymy of C. ruffus, (2) list the taxon C. rufa var. javanica as species inquirenda, and (3) synonymize C. mirzae with C. ruffus. We provide additional evidence to confirm that the type locality of C. ruffus is Java. Cylindrophis subocularis sp. nov. is the second species of Asian pipesnake from Java.

A new species of the gekkonid lizard genus Cyrtodactylus Gray, 1827 is described from Klakah, Lumajang Regency, Jawa Timur Province, Java, Indonesia. Cyrtodactylus klakahensis sp. nov. can be distinguished from all other congeners by the presence of (1) a deep precloacal groove in males, (2) three rows of enlarged precloacofemoral scales, of which the third row bears 37–38 pores in males, (3) three or four rows of enlarged scales between the precloacofemoral scale rows and the cloaca, forming distinct chevrons, (4) raised and strongly keeled dorsal tubercles in 15–19 rows at midbody, (5) an indistinct lateral fold, (6) 17–20 subdigital lamellae under the 4 th toe, and (7) subcaudal scales which are not transversely enlarged. Cyrtodactylus klakahensis sp. nov. is only the third bent-toed gecko species described from Java, indicating that the diversity of this genus on this island has been neglected in the past. Furthermore, we confirm that C . fumosus (Muller, 1895) is a species that possesses a precloacal groove in males and is most likely restricted to northern Sulawesi. That species is defined by a single female holotype (NMB-REPT 2662). Specimens in museum collections catalogued as C . fumosus from localities elsewhere are misidentified and likely represent undescribed species.