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The viscous shearing of the cooling oil within disengaged wet clutches causes a substantial amount of power loss. In order to optimise efficiency, it is the objective of current research to minimise these losses to a great extent. In addition to test rig measurements effective calculation tools are desirable. This contribution deals with highly detailed numerical simulation of the flow in disengaged wet clutch discs with radial and complex groove designs. For this purpose a transient 3D CFD simulation model is presented. The calculation results are compared with test rig measurements and high-speed video recordings of the phase distribution. By variation of the operating conditions as well as various geometric parameters, the general validity of the model is shown.

Anticipatory coping involves efforts to reduce the consequences of upcoming, future stressors, but the individual and contextual predictors of anticipatory coping are not well understood. The current study focuses on individual differences in age and income and contextual fluctuations in mindfulness (present-centered thinking) to predict daily fluctuations in anticipatory coping with future home-related stressors. In the Mindfulness and Anticipatory Coping Everyday study, 223 adults (116 aged 60–90, 107 aged 18–36) completed an online questionnaire for nine consecutive days via Qualtrics, providing demographic information on Day 1. For the subsequent 8 days, participants reported mindfulness and anticipatory coping. Multilevel models revealed that within-person increases in daily mindfulness were related to decreases in daily anticipatory coping among younger adults and higher income older adults. This research provides evidence of tension between mindfulness and future-oriented coping and shows how this depends on one's life stage and access to resources.

Social parasites exploit resources of other social species, to the detriment of their host. In order to enter and integrate in a host colony, social parasites must avoid being detected as a non-nestmate. The parasites, therefore, use one or a combination of chemical strategies: (1) producing recognition cues that match host's (mimicry), (2) acquiring recognition cues from the hosts or its nest (camouflage), (3) not producing recognition cues (insignificance) and/or (4) using substances for confusing, suppressing or appeasing the host (weaponry). In this study, we investigate the integration strategy of Megalomyrmex symmetochus ants into colonies of the fungus-growing ant Sericomyrmex amabilis. We compared the chemical odour profiles of parasitized and nonparasitized S. amabilis colonies with the profiles of the parasites. Additionally, we conducted behavioural assays, where we introduced a single ant, being either a nestmate, a conspecific non-nestmate or a parasite into an arena with five S. amabilis workers and scored the behaviour of the latter ants. The chemical analysis revealed that the social parasites have distinct odour profiles and share only one hydrocarbon with its host, have a low overall abundance of cuticular hydrocarbons and have high concentrations of venom-derived alkaloids. In behavioural experiments, we found that workers of nonparasitized colonies fight against parasite intruders, whereas workers of parasitized colonies treat introduced parasites (from their own and from another parasitized colony) similar to their conspecific nestmates. All workers (parasitized or not) show more submissive behaviour towards parasitized workers and parasites than towards nonparasitized workers. The chemical analysis of odour profiles suggests that the parasites use a chemical insignificance strategy. Furthermore, the chemical and behavioural data suggest that the parasites use weaponry to maintain an amiable association with their host ants. We discuss the biological significance of the lack of aggression in S. amabilis workers from parasitized colonies.

Within disengaged wet-running multi-plate clutches a certain drag torque is generated as a result of the differential speed between the discs. These losses can be reduced providing uniform clearances within the clutch pack. To this end, reliable and uniform separation of the discs should be achieved, which can be realized using both mechanical components and hydrodynamic pressure of the oil flow. This paper deals with a method for measuring the hydrodynamic axial force generated by wet clutch discs. This system allows the determination of the correlation between the axial force and the operating parameters of the clutch and the groove design. Using the examples of a radial and a complex grooving, the measurements are validated with 3D CFD simulation results.

By transcriptome analysis, we identified PBAN and CAPA precursors in the moths Spodoptera littoralis and Heliothis peltigera which are among the most damaging pests of agriculture in tropical and subtropical Africa as well as in Mediterranean countries. A combination of mass spectrometry and immunocytochemistry was used to identify mature peptides processed from these precursors and to reveal their spatial distribution in the CNS. We found that the sites of expression of pban genes, the structure of PBAN precursors and the processed neuropeptides are very similar in noctuid moths. The sequence of the diapause hormone (DH; tryptopyrokinin following the signal peptide), however, contains two N-terminal amino acids more than expected from comparison with already published sequences of related species. Capa genes of S. littoralis and H. peltigera encode, in addition to periviscerokinins, a tryptopyrokinin showing sequence similarity with DH, which is the tryptopyrokinin of the pban gene. CAPA peptides, which were not known from any noctuid moth so far, are produced in cells of abdominal ganglia. The shape of the release sites of these hormones in H. peltigera represents an exceptionally derived trait state and does not resemble the well-structured abdominal perisympathetic organs which are known from many other insects. Instead, axons of CAPA cells extensively ramify within the ventral diaphragm. The novel information regarding the sequences of all mature peptides derived from pban and capa genes of H. peltigera and S. littoralis now enables a detailed analysis of the bioactivity and species-specificity of the native peptides, especially those from the hitherto unknown capa genes, and to explore their interactions with PBAN/DH receptors.

For stationary gas turbines, the injection of water sprays into the compressor inlet is used to increase the power output, which can be used for rapid correction of power fluctuations appearing in power supply systems with today’s increased use of wind and solar energy. However, to fully utilize this technique a comprehensive understanding of the underlying phenomena is needed. An inhouse CFD program was used at Institute of Aerospace Thermodynamics (ITLR) Stuttgart modeling a variety of two-phase phenomena which was validated on the transonic wind tunnel at Helmut Schmidt University (HSU) Hamburg. The present paper focuses on the water film on the blades formed by water deposition of impinged droplets. Experimental results using a reflective shadowgraphy method reveal the wall film pattern on the blade without disturbing the flow. A numerical model is presented predicting the position of film breakup based on the superposition of a small perturbation of the film height. The onset of film breakup is predicted to be at the position in which the perturbation is not dampened by the acting forces. The film breakup position is analyzed experimentally and numerically for three different water loads. The experimental analysis shows that the onset of film breakup is almost independent of the water load. The numerical model shows the same trends and indicates a film breakup at the same position.

We examined how proactive coping and daily mindfulness may work together to predict emotional reactivity to daily stressors. Using data from the Mindfulness and Anticipatory Coping Everyday study (MACE; Neupert & Bellingtier, 2017 ; Neupert & Bellingtier, 2019 ), 116 older adults and 107 younger adults participated in a daily diary study for nine consecutive days. Results from multilevel models suggest that people high in proactive coping were more emotionally reactive to daily stressors on days with decreased mindfulness. Due to the trait-like future-oriented thinking of proactive coping and the state-like present-oriented aspect of daily mindfulness, these results underscore the importance of simultaneously considering state and trait information to elucidate antecedents, correlates, and consequences of daily stressors.

Translocation of the majority of mitochondrial proteins from the cytosol into mitochondria requires the cooperation of TOM and TIM23 complexes in the outer and inner mitochondrial membranes. The molecular mechanisms underlying this cooperation remain largely unknown. Here, we present biochemical and genetic evidence that at least two contacts from the side of the TIM23 complex play an important role in TOM-TIM23 cooperation in vivo. Tim50, likely through its very C-terminal segment, interacts with Tom22. This interaction is stimulated by translocating proteins and is independent of any other TOM-TIM23 contact known so far. Furthermore, the exposure of Tim23 on the mitochondrial surface depends not only on its interaction with Tim50 but also on the dynamics of the TOM complex. Destabilization of the individual contacts reduces the efficiency of import of proteins into mitochondria and destabilization of both contacts simultaneously is not tolerated by yeast cells. We conclude that an intricate and coordinated network of protein-protein interactions involving primarily Tim50 and also Tim23 is required for efficient translocation of proteins across both mitochondrial membranes.

Loss of haptic feedback is one major drawback of telerobotic surgery systems. For this reason tasks of passive input devices can be taken over by haptic user interfaces. The main objective of this paper is the development of a haptic user interface with a kinematic structure matching the slave robot's kinematic structure. In addition, we focus on the detailed design and characterization of a haptic input device concerning the grasping degree of freedom. Requirements of the user interface are derived by analyzing the medical application and the structure of the slave robot. Since the user interface and the input device are supposed to provide realistic haptic feedback, static and dynamic behavior of the device is of interest. Electromechanical analogies help to design the dynamic behavior of the haptic input device. A characterization of static and dynamic behavior validates our design process. The implementation of the input device in the overall user interface is shown. The designed user interface, allows controlling the slave robot in three dimensions, rotation along the axis of the main kinematic chain and grasping. The user interfaces kinematic structure is taking the kinematic constrains of the slave kinematic into account. The input device can be handled similar as a forceps with three point precision grip, similar to a common surgical procedure without robotic assistance. The user interface provides haptic feedback in all directions of the kinematic structure.

Within the CLIC (Compact Linear Collider) project, feasibility studies of a photoinjector option for the drive beam as an alternative to its baseline design using a thermionic electron gun (Geschonke et al. [1] ) are on-going. This R&D program covers both the laser and the photocathode side. Cesium antimonide cathodes were produced at CERN by co-deposition onto copper substrates and characterized by photoemission and by XPS (X-ray Photoemission Spectroscopy) analysis. A systematic study on newly produced and used photocathodes was conducted in order to correlate the surface composition to the photoemissive properties.

The first CAPA peptides of insects were identified from Periplaneta americana using extracts of 8000 abdominal perisympathetic organs. The corresponding gene of cockroaches and other basal insects, however, remained undiscovered. Here we identified two capa cDNA transcripts of P. americana. Single cell mass spectrometry of capa neurons in abdominal ganglia yielded a complete coverage of the precursor sequences of both transcripts; with intermediates of precursor processing more prominent in somata than in perisympathetic organs. The processing of the CAPA precursor in P. americana is compared with that in the beetle Tribolium castaneum which was re-evaluated in this study.

Second life for Li-ion batteries is an extensive research area for batteries used in electric vehicles. In this paper the concept is extended for Li-ion cells obtained from discarded consumer electronics. 152 notebook batteries were disassembled, obtaining 1034 cells and recovering 5.44 kW h of storage capacity. A methodology is proposed to transform notebook batteries into characterized cells, and calculate the cost of second life cells. Concerns are addressed about the selection of cells and design of a second life battery. Finally, a method is proposed to select notebook batteries containing cells with more than 70% capacity, by using data saved in their Battery Management System and test results to train a selection algorithm.

Insect neuropeptides are the most diverse and important group of messenger molecules that regulate almost all physiological processes, including behavior. In this study, we performed a combination of matrix assisted laser desorption ionization time of flight (MALDI-TOF) and electrospray ionization quadrupole time of flight (ESI-Q-TOF) mass spectrometry to analyze the peptidome of the brain and the neurohemal organs of the Australian sheep blowfly Lucilia cuprina and compared the data with those of related flies such as the gray flesh fly Sarcophaga (=Neobellieria) bullata; the cabbage root fly Delia radicum, the fruit fly Drosophila melanogaster, and the yellow fever mosquito, Aedes aegypti. Without counting low intensity signals of truncated peptides, 45 neuropeptides arising from 12 neuropeptide genes (adipokinetic hormone, CAPA-peptides, corazonin, extended FMRFamides, SIFamide, insect kinin, short neuropeptide F, NPLP-1 peptides, HUGIN-pyrokinin, sulfakinins, allatostatins A, putative eclosion hormone precursor peptide) were identified; sequences of extended FMRFamides were reported in a separate publication. The remarkable similarity of the peptidome of cyclorraphan flies, which contain a large number of ecologically important species, does not support the development of a species-specific neuropeptide-based insect pest control strategy. However, mass spectrometric approaches as shown here do not cover the entire peptidome or differences at the receptor level and it is possible that group-specific peptide ligands or receptors exist that escaped the detection.

This paper proposes a new perception-based concept for force sensing in haptic systems. By using two different sensing principles, a better adaption to the human sensory system can be achieved. Based on the tactile and kinesthetic parts of haptic perception, this is done using different sensing principles, nominal ranges, bandwidth and degrees of freedom for each part. The requirements of each part are described in detail and possible realizations are investigated. The proposed concept allows for a better quality of haptic feedback at lower costs.

The production of monoclonal antibodies by hybridoma technology is dependent on lymphocytes taken from vertebrates which have to be immunized against the corresponding antigen. We present here our first experiments which should allow the replacement of this in vivo immunization step by an in vitro immunization procedure. This work provides new possibilities for the specific activation of immune cells in order to use them for the generation of antibodies which are not of murine origin. Bone marrow-derived dendritic cells were loaded with antigen and co-cultured with naïve T and B lymphocytes of non-immunized mice. The interaction and activation of the different cell types were investigated by measuring the expression of specific cell surface markers, the release of activation-dependent interleukins and the secretion of antigen-specific antibodies. We could demonstrate that dendritic cells process and present antigen fragments and activate T cells, that T cells proliferate and release activation-induced interleukins, and that B cells maturate under the influence of activated T cells and secrete antigen-specific antibodies.

We have used an in silico approach to identify a gene from the blood-gorging vector, Rhodnius prolixus , that is predicted to produce an insect kinin prepropeptide. The prepropeptide is 398 amino acids in length and can potentially produce a large number of kinin-related peptides following post-translational processing. A comparison with other insect kinin precursor sequences demonstrates greatest conservation at the C-terminal region of the kinin peptides. Multiple peptides predicted from the kinin gene are phenotypically expressed in R. prolixus , as revealed by MALDI-TOF MS MS, including 12 kinins and one kinin precursor peptide (KPP). Six of these peptides are characterized by the typical insect kinin C-terminal motif FX 1 X 2 WGamide and five of these are also found as truncated forms. Five peptides were identified with an atypical, though similar, FX 1 X 2 WAamide C-terminus. There is also peptide with a C-terminal DDNGamide motif and a number of non-amidated peptides.

Surface degradation due to cyclic thermal loading plays a major role in the Accelerating Structures (AS) of the future Compact Linear Collider (CLIC). In this article results on surface degradation of thermally cycled polycrystalline copper as a function of the orientation of surface grains are presented. Samples with different grain sizes were subjected to thermal fatigue using two different methods and were then characterized using roughness measurements and Orientation Imaging Scanning-Electron-Microscopy (OIM-SEM). Samples fatigued by a pulsed laser show the same trend in the orientation-fatigue damage accumulation as the sample fatigued by pulsed Radio-Frequency-heating (RF). It is clearly shown that [1 1 1] surface grains develop significantly more damage than the surface grains oriented in [1 0 0] and three reasons for this behaviour are pointed out. Based on observations performed near grain boundaries, their role in the crack initiation process is discussed. The results are in good agreement with previous findings and can be interpreted on the basis of existing theories. Finally the fatigue effects induced by the two different applied types of thermal cycling are compared.

Heat shock proteins 70 (Hsp70) represent a ubiquitous and conserved family of molecular chaperones involved in a plethora of cellular processes. The dynamics of their ATP hydrolysis-driven and cochaperone-regulated conformational cycle are poorly understood. We used fluorescence spectroscopy to analyze, in real time and at single-molecule resolution, the effects of nucleotides and cochaperones on the conformation of Ssc1, a mitochondrial member of the family. We report that the conformation of its ADP state is unexpectedly heterogeneous, in contrast to a uniform ATP state. Substrates are actively involved in determining the conformation of Ssc1. The J protein Mdj1 does not interact transiently with the chaperone, as generally believed, but rather is released slowly upon ATP hydrolysis. Analysis of the major bacterial Hsp70 revealed important differences between highly homologous members of the family, possibly explaining tuning of Hsp70 chaperones to meet specific functions in different organisms and cellular compartments.

The co-chaperone Hep1 is required to prevent the aggregation of mitochondrial Hsp70 proteins. We have analyzed the interaction of Hep1 with mitochondrial Hsp70 (Ssc1) and the determinants in Ssc1 that make it prone to aggregation. The ATPase and peptide binding domain (PBD) of Hsp70 proteins are connected by a linker segment that mediates interdomain communication between the domains. We show here that the minimal Hep1 binding entity of Ssc1 consists of the ATPase domain and the interdomain linker. In the absence of Hep1, the ATPase domain with the interdomain linker had the tendency to aggregate, in contrast to the ATPase domain with the mutated linker segment or without linker, and in contrast to the PBD. The closest homolog of Ssc1, bacterial DnaK, and a Ssc1 chimera, in which a segment of the ATPase domain of Ssc1 was replaced by the corresponding segment from DnaK, did not aggregate in Delta hep1 mitochondria. The propensity to aggregate appears to be a specific property of the mitochondrial Hsp70 proteins. The ATPase domain in combination with the interdomain linker is crucial for aggregation of Ssc1. In conclusion, our results suggest that interdomain communication makes Ssc1 prone to aggregation. Hep1 counteracts aggregation by binding to this aggregation-prone conformer.

This paper presents an anti-sway and tracking control for harbor mobile cranes. The control objective is the sway-free transportation of the crane's load taking the commands of the crane operator into account. Based on the mathematical model linearizing and stabilizing control laws for the slewing and luffing motion are derived using the input/output linearization approach. The operator's commands are smoothened online by a trajectory generator accounting for input and state constraints. The resulting optimal control problem is solved using the model predictive control approach. The efficiency of the control concept is illustrated with experiments on an industrial harbor mobile crane.

The general type of clay used by potters can often be identified from attributes of the finished ceramic vessel or sherd. This information is important for compositional and sourcing studies and may also shed light on the variables influencing clay choice such as social, economic, and landscape use patterns. Rice paddies are one type of clay source that are readily identifiable in archaeological ceramics. This paper describes rice paddy clays gathered during ethnoarchaeological studies of traditional potters in Paradijon, southern Luzon, the Philippines. We analyze the effects of clay processing and vessel manufacture on these clays and find that the most diagnostic attribute of paddy soils, the iron oxide mottling, is retained in finished vessels.

The first insect allatotropin-related peptide (ATRP) was isolated from head extracts of the adult sphinx moth Manduca sexta [Kataoka H, Toschi A, Li JP, Carney RL, Schooley DA, Kramer SJ. Identification of an allatotropin from adult Manduca sexta. Science 1989;243:1481-3.]. Meanwhile ATRPs are known from different holometabolous insects but only a single ATRP could be identified from hemimetabolous insects [Paemen L, Tips A, Schoofs L, Proost P, Van Damme J, De Loof A. Lom-AG-myotropin: a novel myotropic peptide from the male accessory glands of Locusta migratoria. Peptides 1991;12:7-10.]. This means that the extensive analysis of neuropeptides from Leucophaea maderae and Periplaneta americana, which led to the discovery of many novel insect neuropeptides, did not result in the detection of any ATRP. In this study, we used another approach to find a cockroach ATRP by first identifying Manse-AT immunoreactive neurons in the terminal ganglion that can be stained by retrograde labeling and are suitable for dissection and subsequent mass spectrometric analysis. The peptidomic analysis of these putative ATRP neurons paved the way for the identification of the first cockroach ATRP. MALDI-TOF/TOF tandem mass spectrometry revealed a sequence identity with Locmi-AG-MT-1 which classifies this ATRP as a highly conserved neuropeptide. A mass spectrometric screening of the nervous system allowed the detection of ATRP-ion signals in different parts of the CNS of P. americana as well as L. maderae. The data obtained in this study will be incorporated in a map of peptidergic neurons from the CNS of the American cockroach, P. americana.

The TIM23 complex is the major translocase of the mitochondrial inner membrane responsible for the import of essentially all matrix proteins and a number of inner membrane proteins. Tim23 and Tim50, two essential proteins of the complex, expose conserved domains into the intermembrane space that interact with each other. Here, we describe in vitro reconstitution of this interaction using recombinantly expressed and purified intermembrane space domains of Tim50 and Tim23. We established two independent methods, chemical cross-linking and surface plasmon resonance, to track their interaction. In addition, we identified mutations in Tim23 that abolish its interaction with Tim50 in vitro. These mutations also destabilized the interaction between the two proteins in vivo, leading to defective import of preproteins via the TIM23 complex and to cell death at higher temperatures. This is the first study to describe the reconstitution of the Tim50-Tim23 interaction in vitro and to identify specific residues of Tim23 that are vital for the interaction with Tim50.

Biogenesis of mitochondria depends on the coordinated action of at least six protein translocases present in both mitochondrial membranes. They use different energy sources to drive unidirectional transport of proteins across and into mitochondrial membranes. Here we present an overview on the energetic requirements of different mitochondrial import pathways.

N-linked glycosylation is an essential posttranslational modification of proteins in eukaryotes. The substrate of N-linked glycosylation, dolichol pyrophosphate (DolPP)-GlcNAc(2)Man(9)Glc(3), is assembled through a complex series of ordered reactions requiring the translocation of the intermediate DolPP-GlcNAc(2)Man(5) structure across the endoplasmic-reticulum membrane. A young patient diagnosed with a congenital disorder of glycosylation characterized by an intracellular accumulation of DolPP-GlcNAc(2)Man(5) was found to carry a homozygous point mutation in the RFT1 gene. The c.199C--T mutation introduced the amino acid substitution p.R67C. The human RFT1 protein shares 22% identity with its yeast ortholog, which is involved in the translocation of DolPP-GlcNAc(2)Man(5) from the cytosolic into the lumenal side of the endoplasmic reticulum. Despite the low sequence similarity between the yeast and the human RFT1 proteins, we demonstrated both their functional orthology and the pathologic effect of the human p.R67C mutation by complementation assay in Deltarft1 yeast cells. The causality of the RFT1 p.R67C mutation was further established by restoration of normal glycosylation profiles in patient-derived fibroblasts after lentiviral expression of a normal RFT1 cDNA. The definition of the RFT1 defect establishes the functional conservation of the DolPP-GlcNAc(2)Man(5) translocation process in eukaryotes. RFT1 deficiency in both yeast and human cells leads to the accumulation of incomplete DolPP-GlcNAc(2)Man(5) and to a profound glycosylation disorder in humans.