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Engineered Geothermal Systems (EGS) are promising, but high-risk targets for baseline energy generation. Technology breakthrough is needed to lower the high risks from largely unknown geologic variables and the limited control of the coolant flow field underground. A new, robust EGS (REGS) arrangement and creation technology is reviewed featuring innovative fracture opening, stabilization and permeability control. The geometry, aperture support technique and coolant fluid flow isolation system are all robustly planned and created according the inventive concept. The new elements of the REGS technology are (1) the step-by-step creation, control, and tests of hydraulic fracturing to achieve a planar wing fracture or fractures osculating along the well trajectory; (2) fracture stabilization by hardening grouting injection to create a central support island in each planar wing fracture for zonal isolation; and (3) well-fracture-well fluid circulation for geothermal energy extraction from single, or clustered planar fractures as geothermal heat exchangers. The paper reviews ongoing tests to prove the key components of the REGS geologic heat exchanger with stabilized, large fracture aperture and controlled flow zones for minimized opening pressure loss, seismicity and maximized energy extraction. Flow fields and heat transport are reviewed around zonal isolation of fracture flow by a grouted, blocking island for heat exchange. The robustness is reviewed for the step-by-step construction of a REGS. The paper reports new results from using numerical, coolant flow and heat exchange models to demonstrate the geothermal energy potential of a single REGS well drilled in hot, dry rock.

This editorial highlights the findings of McMahon [1] and demonstrates the need for careful attention to experimental conditions that influence microbubble concentration and pharmacokinetics contributed to focused ultrasound-induced blood brain barrier opening and sterile inflammation.

Magnetic resonance imaging (MRI)-guided pulsed focused ultrasound (pFUS) combined with microbubbles (MB) contrast agent infusion has been shown to transiently disrupt the blood-brain barrier (BBBD), increasing the delivery of neurotherapeutics to treat central nervous system (CNS) diseases. pFUS interaction with the intravascular MB results in acoustic cavitation forces passing through the neurovascular unit (NVU), inducing BBBD detected on contrast-enhanced MRI. Multiple pFUS+MB exposures in Alzheimer's disease (AD) models are being investigated as a method to clear amyloid plaques by activated microglia or infiltrating immune cells. Since it has been reported that pFUS+MB can induce a sterile inflammatory response (SIR) [1-5] in the rat, the goal of this study was to investigate the potential long-term effects of SIR in the brain following single and six weekly sonications by serial high-resolution MRI and pathology. Methods: Female Sprague Dawley rats weighing 217±16.6 g prior to sonication received bromo-deoxyuridine (BrdU) to tag proliferating cells in the brain. pFUS was performed at 548 kHz, ultrasound burst 10 ms and initial peak negative pressure of 0.3 MPa (in water) for 120 s coupled with a slow infusion of ~460 µL/kg (5-8×107 MB) that started 30 s before and 30 s during sonication. Nine 2 mm focal regions in the left cortex and four regions over the right hippocampus were treated with pFUS+MB. Serial high-resolution brain MRIs at 3 T and 9.4 T were obtained following a single or during the course of six weekly pFUS+MB resulting in BBBD in the left cortex and the right hippocampus. Animals were monitored over 7 to 13 weeks and imaging results were compared to histology. Results: Fewer than half of the rats receiving a single pFUS+MB exposure displayed hypointense voxels on T2*-weighted (w) MRI at week 7 or 13 in the cortex or hippocampus without differences compared to the contralateral side on histograms of T2* maps. Single sonicated rats had evidence of limited microglia activation on pathology compared to the contralateral hemisphere. Six weekly pFUS+MB treatments resulted in pathological changes on T2*w images with multiple hypointense regions, cortical atrophy, along with 50% of rats having persistent BBBD and astrogliosis by MRI. Pathologic analysis of the multiple sonicated animals demonstrated the presence of metallophagocytic Prussian blue-positive cells in the parenchyma with significantly (p

Intramural Research Program of the Clinical Center at the National Institutes of Health Intramural Research Program of the National Institute of Biomedical Imaging and Bioengineering at the National Institutes of Health Stem cell-based therapies have become a major focus in regenerative medicine and to treat diseases. A straightforward approach combining three drugs, heparin (H), protamine (P) with ferumoxytol (F) in the form of nanocomplexes (NCs) effectively labeled stem cells for cellular MRI. We report on the physicochemical characteristics for optimizing the H, P, and F components in different ratios, and mixing sequences, producing NCs that varied in hydrodynamic size. NC size depended on the order in which drugs were mixed in media. Electron microscopy of HPF or FHP showed that F was located on the surface of spheroidal shaped HP complexes. Human stem cells incubated with FHP NCs resulted in a significantly greater iron concentration per cell compared to that found in HPF NCs with the same concentration of F. These results indicate that FHP could be useful for labeling stem cells in translational studies in the clinic. Published by Elsevier Inc. Ctr Clin, Lab Diagnost Radiol Res Radiol & Imaging Sci, Bethesda, MD USA NIH, Frank Lab Radiol & Imaging Sci, Ctr Clin, Bethesda, MD 20892 USA Natl Inst Biomed Imaging & Bioengn, Lab Cellular Imaging & Macromol Biophys, NIH, Bethesda, MD USA Natl Inst Biomed Imaging & Bioengn, NIH, Bethesda, MD USA Univ Fed Sao Paulo, Dept Biochem, Sao Paulo, Brazil Univ Fed Sao Paulo, Dept Biochem, Sao Paulo, Brazil Web of Science

In spite of enormous efforts there have been no solutions to date for preventing/terminating certain acute and chronic disorders of humans by vaccination or drugs. Yet it is well understood that if the target antigen (ag) could be presented appropriately to the cells of the immune system then solutions could be found. Recently, the Barabas research group has introduced and described the third vaccination method - called modified vaccination technique (MVT) - which has the ability to provide a corrective immune response in experimental animals with an autoimmune kidney disease. Injections of immune complexes - made up of the target ag and specific non-pathogenic IgM antibodies directed against the target ag - achieved downregulation of pathogenic immune responses and tolerance to self was regained. Utilizing the immune system's natural abilities to respond to corrective information, the MVT technique was able to prevent an autoimmune kidney disease from occurring (prophylactic effect) in experimental animals, and when present, terminating it (therapeutic effect) specifically and without measurable side effects.It is predicted that the application of the MVT will have the potential in the future to revolutionize the preventative and therapeutic options for dealing with chronic disorders in humans (such as autoimmune disease, cancer and acute chronic infections) and achieve cures.

Background Magnetic resonance imaging (MRI)-guided pulsed focused ultrasound combined with the infusion of microbubbles (pFUS+MB) induces transient blood-brain barrier opening (BBBO) in targeted regions. pFUS+MB, through the facilitation of neurotherapeutics’ delivery, has been advocated as an adjuvant treatment for neurodegenerative diseases and malignancies. Sterile neuroinflammation has been recently described following pFUS+MB BBBO. In this study, we used PET imaging with [18F]-DPA714, a biomarker of translocator protein (TSPO), to assess for neuroinflammatory changes following single and multiple pFUS+MB sessions. Methods Three groups of Sprague-Dawley female rats received MRI-guided pFUS+MB (Optison™; 5–8 × 107 MB/rat) treatments to the left frontal cortex and right hippocampus. Group A rats were sonicated once. Group B rats were sonicated twice and group C rats were sonicated six times on weekly basis. Passive cavitation detection feedback (PCD) controlled the peak negative pressure during sonication. We performed T1-weighted scans immediately after sonication to assess efficiency of BBBO and T2*-weighted scans to evaluate for hypointense voxels. [18F]DPA-714 PET/CT scans were acquired after the BBB had closed, 24 h after sonication in group A and within an average of 10 days from the last sonication in groups B and C. Ratios of T1 enhancement, T2* values, and [18F]DPA-714 percent injected dose/cc (%ID/cc) values in the targeted areas to the contralateral brain were calculated. Histological assessment for microglial activation/astrocytosis was performed. Results In all groups, [18F]DPA-714 binding was increased at the sonicated compared to non-sonicated brain (%ID/cc ratios > 1). Immunohistopathology showed increased staining for microglial and astrocytic markers in the sonicated frontal cortex compared to contralateral brain and to a lesser extent in the sonicated hippocampus. Using MRI, we documented BBB disruption immediately after sonication with resolution of BBBO 24 h later. We found more T2* hypointense voxels with increasing number of sonications. In a longitudinal group of animals imaged after two and after six sonications, there was no cumulative increase of neuroinflammation on PET. Conclusion Using [18F]DPA-714 PET, we documented in vivo neuroinflammatory changes in association with pFUS+MB. Our protocol (utilizing PCD feedback to minimize damage) resulted in neuroinflammation visualized 24 h post one sonication. Our findings were supported by immunohistochemistry showing microglial activation and astrocytosis. Experimental sonication parameters intended for BBB disruption should be evaluated for neuroinflammatory sequelae prior to implementation in clinical trials., Journal of Neuroinflammation, 16 (1), ISSN:1742-2094

We thank Silburt et al. (1) for their comments on our article (2). The authors provide us with an opportunity to expand on sterile inflammation in the brain induced by pulsed focused ultrasound (pFUS) (3). pFUS with microbubbles (MB) resulting in blood–brain barrier disruption (BBBD) is accompanied by plasma protein extravasation into the extracellular space. Fundamentally, any BBBD is a nonhomeostatic condition and leakage of albumin activates microglia and astrocytes (4). To appropriately contextualize our biological data (2), we must make a few technical notes. Silburt et al. (1) accurately point out that many techniques in the FUS field are plagued by lack of rigorous optimization. Accordingly, our study … [↵][1]1To whom correspondence may be addressed. Email: zsofia.kovacs{at}nih.gov or jfrank{at}helix.nih.gov. [1]: #xref-corresp-1-1

The paper presents the control architecture of the PENTROB reconfigurable parallel robot with five degrees of freedom, pointing out several ways of reducing the electric energy consumption. Based on the implicit functions which characterize the relation between the coordinates of the active joints and the end-effector pose, the control functions are determined. The control program of the robot is described, presenting the internal architecture of the software and hardware components together with the man-machine interface which provides four possibilities of controlling the robot. The energy consumption reduction is approached through several different ways: the use of an intelligent driver, the configuration of the driver using the advanced microstepping control technique.

MRI-guided pulsed focused ultrasound (pFUS) combined with systemic infusion of ultrasound contrast agent microbubbles (MB) causes localized blood-brain barrier (BBB) disruption that is currently being advocated for increasing drug or gene delivery in neurological diseases. The mechanical acoustic cavitation effects of opening the BBB by low-intensity pFUS+MB, as evidenced by contrast-enhanced MRI, resulted in an immediate damage-associated molecular pattern (DAMP) response including elevations in heat-shock protein 70, IL-1, IL-18, and TNFα indicative of a sterile inflammatory response (SIR) in the parenchyma. Concurrent with DAMP presentation, significant elevations in proinflammatory, antiinflammatory, and trophic factors along with neurotrophic and neurogenesis factors were detected; these elevations lasted 24 h. Transcriptomic analysis of sonicated brain supported the proteomic findings and indicated that the SIR was facilitated through the induction of the NFκB pathway. Histological evaluation demonstrated increased albumin in the parenchyma that cleared by 24 h along with TUNEL+ neurons, activated astrocytes, microglia, and increased cell adhesion molecules in the vasculature. Infusion of fluorescent beads 3 d before pFUS+MB revealed the infiltration of CD68+ macrophages at 6 d postsonication, as is consistent with an innate immune response. pFUS+MB is being considered as part of a noninvasive adjuvant treatment for malignancy or neurodegenerative diseases. These results demonstrate that pFUS+MB induces an SIR compatible with ischemia or mild traumatic brain injury. Further investigation will be required before this approach can be widely implemented in clinical trials.

Enhanced visual detail processing in subjects with pervasive developmental disorder (PDD) has been related to impairments in feature integration. The functional integrity of two types of neuronal connections involved in visual feature integration, namely horizontal and feedbackward connections, were tested. Sixteen children with PDD and 17 age- and IQ-matched control children (mean age 13.3 years) were included. In a texture segregation task the difference in ERP response to homogeneous and checkered visual stimuli was determined. Additionally, in a contour integration task subjects had to point out a contour consisting of colinearly aligned Gabor signals in backgrounds increasing in noise. Children with PDD showed a normal performance on the contour integration task, suggesting that neurons in the primary visual cortex of children with PDD can effectively integrate the activity of local detectors that process different aspects of the same object information by making use of long-range lateral connections. The amplitude of ERP activity related to texture segregation was also not different between the PDD and control groups, indicating functional visual feedback mechanisms between V I and higher order areas in subjects with PDD. However, a difference in latency of texture-segmentation related activity between the groups was noted. This effect did not reach significance, which could be due to the small N of the study. Therefore, the data need replication in a study with larger samples before more definitive conclusions can be drawn.

Automated detection of prostate cancer in digitized H and E whole-slide images is an important first step for computer-driven grading. Most automated grading algorithms work on preselected image patches as they are too computationally expensive to calculate on the multi-gigapixel whole-slide images. An automated multi-resolution cancer detection system could reduce the computational workload for subsequent grading and quantification in two ways: by excluding areas of definitely normal tissue within a single specimen or by excluding entire specimens which do not contain any cancer. In this work we present a multi-resolution cancer detection algorithm geared towards the latter. The algorithm methodology is as follows: at a coarse resolution the system uses superpixels, color histograms and local binary patterns in combination with a random forest classifier to assess the likelihood of cancer. The five most suspicious superpixels are identified and at a higher resolution more computationally expensive graph and gland features are added to refine classification for these superpixels. Our methods were evaluated in a data set of 204 digitized whole-slide H and E stained images of MR-guided biopsy specimens from 163 patients. A pathologist exhaustively annotated the specimens for areas containing cancer. The performance of our system was evaluated using ten-fold cross-validation, stratified according to patient. Image-based receiver operating characteristic (ROC) analysis was subsequently performed where a specimen containing cancer was considered positive and specimens without cancer negative. We obtained an area under the ROC curve of 0.96 and a 0.4 specificity at a 1.0 sensitivity.

Although the pathogenesis of Parkinson's disease (PD) remains unknown, it appears that microglial activation is associated with enhanced neurodegeneration in animal models of PD as well as in PD patients. Experimentally, C57BL/6 and SWR/J mice demonstrate striking differences in the extent of dopaminergic (DAergic) neurodegeneration induced by a parkinsonian toxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The purpose of this study was to determine whether differences in microglial activation between these two strains of mice could provide insight into the variability seen in toxicant induced neuronal death, and subsequently to use a high-throughput proteomic method, combining stable isotope labeling with amino acids in cell culture (SILAC) with liquid chromatography and tandem mass spectrometry, to compare the microglial proteomes of C57BL/6 and SWR/J mice after stimulation with a classical microglial activator, lipopolysaccharide (LPS). We found that DAergic neurotoxicity induced by LPS in a primary neuron–microglia coculture was twofold greater with microglia isolated from the brains of C57BL/6 mice compared with that of SWR/J mice. Upon proteomic analysis we found that, out of over 1000 proteins identified and quantified, 400 displayed a significant difference in their relative abundance between these two murine strains. Several proteins, which had relatively higher levels in C57BL/6 mice, have previously been implicated in LPS-mediated microglial activation, including those involved in the COX-2 pathway and in prostaglandin E-2 (PGE2) production. To validate our proteomic results we confirmed the increased expression level of iNOS in C57BL/6 vs. SWR/J microglia with semiquantitative Western blot. Further analysis of our proteomic discovery data will likely reveal numerous novel proteins involved in inflammation-mediated neurotoxicity in PD. © 2006 Wiley-Liss, Inc.

Beauty is a powerful force that affects both our emotions and our ecological practices, yet aesthetic values remain understated and under-discussed in ecology. Here we invite discussion about the influence of beauty on ecological research by outlining: 1) how aesthetics affect the practice of ecology, and 2) how aesthetics affect the implementation of ecological research on the landscape. The aesthetic sensibilities of ecologists develop through personal experiences and are enriched by professional training, including ecological coursework, fieldwork, research and discussion. Many ecologists choose an ecological career because it offers an opportunity to work in beautiful, natural places. However, these values influence assessments of landscapes as beautiful, sustainable, functioning or threatened. Beauty and concepts of aesthetic preference may have strong influences on the design, implementation and inter - pretation of ecological studies as well as public perceptions of ecological processes.

Neuroinflammation mediated by microglial activation appears to play an essential role in the pathogenesis of Parkinson disease; however, the mechanisms by which microglia are activated are not fully understood. Thus, we first evaluated the effects of two parkinsonian toxicants, manganese ethylene bisdithiocarbamate (Mn-EBDC) and 1-methyl-4-phenylpyridine (MPP+), on microglial activation as well as associated dopaminergic (DAergic) neurotoxicity in primary cell culture systems. The results demonstrated that, when rat primary mesencephalic neuron-enriched or neuron-microglia mixed cultures were treated with Mn-EBDC at 2-8 microm or MPP+ at 0.25-5 microm, respectively, for 7 days, both toxicants were capable of inducing DAergic neurodegeneration as well as activating microglia via a mechanism secondary to DAergic neurodegeneration. Furthermore activated microglia subsequently enhanced DAergic neurotoxicity induced by Mn-EBDC or MPP+. Detailed scrutiny of neuron-microglia interactions identified a fraction of the conditioned media derived from a DAergic cell line treated with Mn-EBDC or MPP+ that potently activated microglia. To further define potential mediators leading to microglial activation secondary to neurodegeneration, we utilized a quantitative proteomic technique termed SILAC (for stable isotope labeling by amino acids in cell culture) to compare the protein profiles of MPP+-treated cellular fraction that mediated microglial activation as compared with controls. The search revealed numerous novel proteins that are potentially important in neurodegeneration-mediated microglial activation, a process believed to be critical in Parkinson disease progression.

Our aim was to obtain an objective evaluation of the airway before and after reversible glottis-dilating operations using the lung function test. Bilateral abductor vocal cord paralysis remains mostly a complication of thyroid surgery. After thyroid surgery, the paralysis is potentially reversible, and the patient has a chance for recovery mostly in the first 6 months. According to these considerations, a reversible vocal cord laterofixation procedure was used instead of tracheostomy. The operations were performed endoscopically using high-frequency JET ventilation and the special endo-extralaryngeal suture technique by Lichtenberger. This technique was used in 92 cases. The pre- and postoperative data of reversible glottis-dilating techniques could be compared in 23 non-selected patients. Lung function tests that were performed were forced inspiratory volume (FIV1), forced expiratory volume (FEV1), peak inspiratory flow rate (PIF), peak expiratory flow rate (PEF) and resistance of the airways (Raw). For the evaluation of the functional results, we used the body-pletysmograph. Our aim was to obtain a quantitative evaluation of the results. These values allow us to compare the results achieved by using different glottis-dilating methods. The FEV1 (forced expiratory volume) improved 25%, and the FIV1 (forced inspiratory volume) improved 39% after the operations on average. PEF (peak expiratory flow rate) and PIF (peak inspiratory flow rate) improved 37 and 45% after glottis-dilating surgery on average. The Raw (resistence of airways) was 271.5% on average before the operations, and after reversible glottis-dilating operations decreased to a level of 200.6%.

This paper presents different control system for parallel robots. The PARMIS robot is used in minimally invasive surgery. PARMIS robotic system consists of three robotic arms PARAMIS and PARASURG-9M right hand and left hand. PARASURG-9M arm consists of PARASURG 5M and left robotic PARASIM, a dexterous 4-DOFS surgical instrument. The paper presents the kinematic structure of each the control system unit structure, algorithms and software implemented, user interfaces, and conclusion.

Learning how to separate benign confounders from prostate cancer is important because the imaging characteristics of these confounders are poorly understood. Furthermore, the typical representations of the MRI parameters might not be enough to allow discrimination. The diagnostic uncertainty this causes leads to a lower diagnostic accuracy. In this paper a new cascaded classifier is introduced to separate prostate cancer and benign confounders on MRI in conjunction with specific computer-extracted features to distinguish each of the benign classes (benign prostatic hyperplasia (BPH), inflammation, atrophy or prostatic intra-epithelial neoplasia (PIN). In this study we tried to (1) calculate different mathematical representations of the MRI parameters which more clearly express subtle differences between different classes, (2) learn which of the MRI image features will allow to distinguish specific benign confounders from prostate cancer, and (2) find the combination of computer-extracted MRI features to best discriminate cancer from the confounding classes using a cascaded classifier. One of the most important requirements for identifying MRI signatures for adenocarcinoma, BPH, atrophy, inflammation, and PIN is accurate mapping of the location and spatial extent of the confounder and cancer categories from ex vivo histopathology to MRI. Towards this end we employed an annotated prostatectomy data set of 31 patients, all of whom underwent a multi-parametric 3 Tesla MRI prior to radical prostatectomy. The prostatectomy slides were carefully co-registered to the corresponding MRI slices using an elastic registration technique. We extracted texture features from the T2-weighted imaging, pharmacokinetic features from the dynamic contrast enhanced imaging and diffusion features from the diffusion-weighted imaging for each of the confounder classes and prostate cancer. These features were selected because they form the mainstay of clinical diagnosis. Relevant features for each of the classes were selected using maximum relevance minimum redundancy feature selection, allowing us to perform classifier independent feature selection. The selected features were then incorporated in a cascading classifier, which can focus on easier sub-tasks at each stage, leaving the more difficult classification tasks for later stages. Results show that distinct features are relevant for each of the benign classes, for example the fraction of extra-vascular, extra-cellular space in a voxel is a clear discriminator for inflammation. Furthermore, the cascaded classifier outperforms both multi-class and one-shot classifiers in overall accuracy for discriminating confounders from cancer: 0.76 versus 0.71 and 0.62.

The AMPA-type glutamate receptor subunits GluR1 and GluR2/3 were localized by immunohistochemistry with subunit-specific antibodies in hippocampi removed surgically from patients with temporal lobe epilepsy for the control of seizures. The flip and flop splice variants of the subunits were localized by in situ hybridization histochemistry with specific oligoprobes. In patient hippocampi that were not the seizure focus, the GluR1 subunit proteins were diffusely expressed on the dendrites of neurons in all regions. In contrast, in these same hippocampi, the GluR2/3 subunit proteins were expressed strongly on the soma and proximal dendrites of principal neurons in all regions. The flip variant of these subunits was localized in the hilus and fields of Ammon's Horn (CA), while the flop variants were prominent on the dentate granule cells. In the epileptogenic hippocampus, while immunoreactivity was decreased in all fields that showed neuronal loss, there was an increased expression of GluR1 on the dendritic excrescences on the proximal dendrites of hilar neurons and CA3 pyramidal neurons, as well as expression of GluR2/3 in hilar neuron excrescences. Electron microscopic examination confirmed that the GluR1 immunoreactivity was only in dendritic processes, particularly dense at the postsynaptic membranes. Such expression of GluR1 may provide for an enhanced glutamatergic response by these neurons. GluR2/3 was also significantly increased on the dendrites of dentate granule cells in the epileptogenic hippocampus and may provide some protection against excitotoxic injury by reducing calcium flux into neurons.

This paper presents an architecture for a fixed-delay tree search with feedback (FDTS/DF) channel which uses a maximum transition run-length code. The critical timing path in this new detector is comparable to that of a decision feedback detector. The forward filter consists of a first-order all-pass filter cascaded with a fourth-order Bessel filter. Timing and gain recovery are also discussed.

[η2-{tBu2PP}Pt(PPh3)2] 1 und [η2-{t Bu2PP}Pt(PEtPh2)2] 2 sind die ersten Komplexverbindungen des tBu2PP 5. Sie entstehen bei der Umsetzung von tBu2PP P(Me)tBu23 mit [η2-{H2CCH2}Pt(PPh3)2] 6 bzw. [η2-{H2C CH2}Pt(PEtPh2)2] 7 unter Abspaltung von tBu2PMe. Verbindung 2 ist bestandiger als 1. Mit tBu2PMe bildet 1 das [η2-{tBu2PP} Pt(PPh3)(PtBu2Mc)] 10. Bei der Umsetzung von 6 mit 3 entsteht ebenfalls 10, weil das bei der Bildung von 1 freiwerdende tBu2PMe mit 1 weiterreagiert. Die Strukturen von 1 und 2 sind uber ihre 1H- und 31P-NMR-Spektren, die von 2 zusatzlich durch eine Rontgenstrukturanalyse gesichert. 2 kristallisiert monoklin in P21/n mit a = 1222,36(7) pm, b = 1770,1(1) pm, c = 1729,7(1) pm, β = 108,653(6)°. Coordination Chemistry of P-rich Phosphanes and Silylphasphanes. XIV. The Phosphinophosphinidene tBu2PP as a Ligand in the Pt Complexes [η2-{tBu2PP}Pt(PPh3)2] and [η2-{tBu2PP}Pt(PEtPh2)2] [η2-{tBu2PP}Pt(PPh3)21 and [η2-{tBu2PP}Pt(PEtPh2)2] 2 are the first complex compounds of tBu2PP 5. They are formed in the reaction of tBu2PP P(Me)tBu23 with [η2-{H2C CH2}Pt(PPh3)2] 6 or [η2-{H2C CH2}Pt(PEtPh2)2] 7, respectively. Compound 1 is less stable than 2 and reacts on to [η2-{tBu2PP} Pt(PPh3)(PtBu2Me)] 10 with the coincidently formed tBu2PMe. The molecular structures of 1 and 2 were derived from their 1H and 31P-NMR spectra, 2 was additionally characterized by a X ray structure determination. 2 crystallizes in the monoclinic space group P21/n with a = 1222.36(7) pm, b = 1770.7(1) pm, c = 1729.7(1) pm, β = 108.653(6)°.

[η2-{tBu2PPPtBu2} PtBr(PPh3)] 1 ist die erste Komplexverbindung aus einem Phosphino-phosphiniden-phosphoran. Die gelben Kristalle von 1, Smp. 201–203°C (unter Zersetzung) bilden sich bei der Umsetzung von tBu2PPP(Br)tBu2 mit (Ph3P)2Pt · C2H4 oder Pt(PPh3)4. 1 kristallisiert triklin in P1 (Nr. 2) mit a = 1076,80(8) pm, b = 1344,61(8) pm, c = 1381,16(9) pm, α = 81,773(6)°, β; = 85,110(8)°, γ = 88,776(7). Coordination Chemistry of P-rich Phosphanes and Silylphosphanes. XIII [1]. [η2-{tBu2PPPtBu2} PtBr(PPh3)] [η2-{tBu2PPPtBu2} PtBr(PPh3)] 1 is the first transition metal complex compound resulting from a phosphino-phosphinidene-phosphorane. The yellow crystals of 1 (fp. 201–203°C, decomp.) were obtained by reacting tBu2PPP(Br)tBu2 with either (Ph3P)2Pt · C2H4, or with Pt(PPh3)4, resp. Compound 1 crystallizes triclinic in the space group P1 (no. 2) with a = 1076.80(8) pm, b = 1344.61(8) pm, c = 1381.16(9) pm, α = 81.773(6)°, β; = 85,110(8), γ = 88,776(7).

tBu2PPP(Br)tBu21 reagiert mit PR3 [R3 Et3, tBu3, Ph3, (NMe2)3, (NEt2)3, (NEt2)2Me, Me2SiMe3] nach tBu2PPP(Br)tBu2 + PR3 tBu2PPPR3 + tBu2PBr Wahrend 1 oberhalb −30°C unter Bildung von tBu2PBr und der Cyclophosphane (tBu2P)3P3, (tBu2P)4P4 zerfallt, unterbleibt die Kondensation des intermediar auftretenden tBu2PP zu den Cyclophosphanen in Anwesenheit von PR3 aufgrund der Addition des Phosphans. Die Chlorphosphane tBu2PCl, tBuPhPCl, (Et2N)2PCl und Ph2PCl sowie (CF3)2PBr reagieren weitgehend entsprechend Gl. (1) unter Bildung von tBu2PPPtBu2Cl, tBu2PPPtBuPhCl, tBu2PPP(NEt2)2Cl, tBu2PPP(NEt2)2Br. Reactions of tBu2PPP(Br)tBu2 with Phosphanes A Route to Variously Substituted Phosphinophosphinidene-phosphoranes tBu2PPP(Br)tBu21 reacts with PR3 [R3 = Et3, tBu3, Ph3, (NMe2)3, (NEt2)3, (NEt2)2Me, Me2SiMe3] according to tBu2PPP(Br)tBu2 + PR3 tBu2PPPR3 + tBu2PBr While 1 decomposes above −30°C yielding tBu2PBr and the cyclophosphanes (tBu2P)3P3 and (tBu2P)4P4, there is no condensation to give any cyclophosphanes from the intermediately formed tBu2PP in the presence of PR3. The chlorophosphanes tBu2PCl, tBuPPhCl, (Et2N)2PCl and Ph2PCl as well as (CF3)2PBr react quite analogously to the above equation yielding tBu2PPP(Cl)tBu2, tBu2PPPtBuPhCl, tBu2PPP(NEt2)2Cl and tBu2PPP(NEt2)2Br.

Es wird uber die Verbindungen (tBu2P)2PSiMe31, Li(THF)2[η2-(tBu2P)2P] 2, Li(TMEDA) · [η2-(tBu2P)2P] 3, Li(THF)2[η2-(iPr2P)2P] 4, Li(THF)2[η2-(Et2N)2PPPtBu2] 5 und Li(THF)2[η2-(tBu2PPPiPr2)] 6 berichtet. Letztere bilden sich durch Umsetzung der entsprechenden silylierten Triphosphane mit nBuLi: 2 und 3 aus (tBu2P)2PSiMe31, 4 aus (iPr2P)2PSiMe3, 5 aus (Et2N)2P · (SiMe3)PtBu2, 6 aus tBu2PP(SiMe3)PiPr2. 1 kristallisiert orthorhombisch in P212121 (Nr. 19) mit a = 910,87(7) pm, b = 1132,5(1) pm, c = 2373,5(2) pm (bei 90 K bestimmt). Die Strukturbestimmung von 2 erfolgte bei 293 K und 200 K. 2 kristallisiert monoklin in P21/n (Nr. 14) mit a = 1069,7(3) pm, b = 1802,5(3) pm, c = 1604,0(7) pm, β = 98,11(2)° (200 K), 3 ebenfalls in P21/n (Nr. 14) mit a = 904,3(2) pm, b = 1936,4(5) pm, c = 1653,2(3) pm, β = 94,52(1)° (200 K). 4 kristallisiert monoklin in C2/c (Nr. 15) mit a = 1650,0(5) pm, b = 945,6(3) pm, c = 1779,8(5) pm, β = 108,81(2)° (200K), 5 in P21/n (Nr. 14) mit a = 939,4(5) pm, b = 1736,8(6) pm, c = 1943,3(7) pm, β = 98,17(4)° (200 K). Alle funf Verbindungen enthalten jeweils vier Formeleinheiten in der Elementarzelle. Es wird uber die Untersuchung der 1H-, 31P- und 7Li-NMR-Spektren der Verbindungen 2–6 berichtet. Formation and Structure of Li(THF)2[η2-(tBu2P)2P], Li(TMEDA)[η2-(tBu2P)2P], Li(THF)2[η2-(iPr2P)2P], Li(THF)2[η2-(Et2N)2PPPtBu2], Li(THF)2[η2-(tBu2PPPiPr2] and (tBu2P)2PSiMe3 The formation and crystal structures of the compounds (tBu2P)2PSiMe31, Li(THF)2[η2-(tBu2P)2P] 2, Li(TMEDA)[η2-(tBu2P)2P] 3, Li(THF)2[η2-(iPr2P)2P] 4, Li(THF)2[η2-(Et2N)2PPPtBu2] 5 and Li(THF)2[η2-(tBu2PPPiPr2)] 6 are reported. Compounds 3–6 are formed by reacting the corresponding silylated triphosphanes with nBuLi: 2 and 3 result from (tBu2P)2PSiMe31, 4 from (iPrP)2PSiMe3, 5 from (Et2N)2PP(SiMe3)PtBu2 and 6 from tBu2PP(SiMe3)PiPr2. 1 crystallizes in the orthorhombic space group P212121 (no. 19) with a = 910.87(7) pm, b = 1132.5(1) pm, c = 2373.5(2) pm (determined at 90 K). The structure determination of 2 was performed at 293 K and 200 K, respectively. 2 crystallizes in the monoclinic space group P21/n (no. 14) with a = 1069.7(3) pm, b = 1802.5(3) pm, c = 1604.0(7) pm, β = 98.11(2)° (200 K); 3 also in P21/n (no. 14) with a = 904.3(2) pm, b = 1936.4(5) pm, c = 1653.2(3) pm, β = 94.52(1)° (200 K). 4 crystallizes monoclinically in C2/c (no. 15) with a = 1650.0(5) pm, b = 945.6(3) pm, c = 1779.8(5) pm, β = 108.81(2)° (200 K); 5 in P21/n (no. 14) with a = 939.4(5) pm, b = 1736.8(6) pm, c = 1943.3(7) pm, β = 98.17(4)° (200 K). All compounds contain Z = 4 molecules in the unit cell. The 1H, 31P and 7Li NMR spectra of 2–6 are discussed.

Die Triphosphane X2PP(SiMe3)PY25, 7, 9, 11, 13 und die entsprechenden Phosphide 6, 8, 10, 12, 14 wurden synthetisiert, 5 und 6 mit X2 = iPr2 und Y2 = tBu2, 7 und 8 mit X2 = Y2 = PhtBu, 9 und 10 mit X2 = tBu2 und Y2 = Ph2, 11 und 12 mit X2 = Y2 = Ph2 sowie 13 und 14 mit X2 = tBu2 und Y2 = (NEt2)2. Die silylierten Triphosphane bilden mit CBr4 in Toluol bei −70°C X2PPP(Br)Y2 und X2PP(Br)PY2, die lithiierten Phosphide mit MeCl Abstand X2PPP(Me)Y2 und X2PP(Me)PY2. Der Reaktionsverlauf ist abhangig von den Gruppen X und Y. Das Bromierungsprodukt von 5 (X2 = iPr2, Y2 = tBu2) ist das Ylid iPrPPP(Br)tBu2, wahrend die Methylierung des entsprechenden Phosphides 6 zu den beiden Yliden iPrPPP(Me)tBu2, tBu2PPP(Me)iPr2 und dem methylierten Triphoshan fuhrt. Von 9 (X2 = tBu2, Y2 = Ph2) wurden sowohl Ph2PPP(Br)tBu2 als auch das bromierte Triphosphan gebildet, von dem entsprechenden Phosphid 10 das Ph2PPP(Me)tBu2 und das methylierte Triphosphan. Verbindung 14 (X2 = tBu2, Y2 = (NEt2)2) reagiert zum bromierten Ylid tBu2PPP(Br)(NEt2)2 und dem bromierten Triphosphan, bei Methylierung zu tBu2PPP(Me)(NEt2)2 und tBu2PP(Me)P(NEt2)2 (Hauptprodukt). Die Br-substituierten Derivate zersetzen sich bereits beim Erwarmen auf −30°C, wahrend die methylierten bis zu 20°C bestandig sind. Concerning the Influence of the Substituents R = Ph, NEt2, iPr, and tBu in Triphosphanes (R2P)2PSiMe3 and Phosphides Li(THF)2[(R2P)2P] on the Formation and Properties of Phosphino-phosphinidene-phosphoranes The triphosphanes X2PP(SiMe3)PY25, 7, 9, 11, 13 and the derived phosphides Li(THF)2[X2PPPY2] 6, 8, 10, 12, 14 were synthesized: 5 and 6 with X2 = iPr2 and Y2 = tBu2, 7 and 8 with X2 = Y2 = PhtBu, 9 and 10 with X2 = tBu2 and Y2 = Ph2, 11 and 12 with X2 = Y2 = Ph2, and 13 and 14 with X2 = tBu2 and Y2 = (NEt2)2. The silylated triphosphanes at −70°C in toluene with CBr4 may yield X2PPP(Br)Y2 and X2PP(Br)PY2, and the lithiated phosphides with MeCl may yield X2PPP(Me)Y2 and X2PP(Me)PY2 depending on X and Y. The bromiated product of 5 (X2 = iPr2, Y2 = tBu2) is the ylide iPr2PPP(Br)tBu2, and the methylated derivatives of 6 are both iPr2PPP(Me)tBu2, tBu2PPP(Me)iPr and the methylated triphosphane. Ph2PPP(Br)tBu2 as well as the brominated triphosphane are obtained from 9 (X2 = tBu2, Y2 = Ph2), and similarly Ph2PPP(Me)tBu2 and the methylated triphosphane from 10. Compound 14 (X2 = tBu2, Y2 = (NEt2)2 gives rise to the brominated ylide tBu2)PPP(Br) · (NEt2)2 and to the brominated triphosphane, and on methylation to tBu2PPP(Me)(NEt2)2 and to tBu2PP(Me)P · (NEt2)2 (main product). The Br substituted derivatives decompose already on warming to −30°C, while the methylated compounds are stable up to 20°C.

Es wird uber die Bildung von tBu2PP = P · (R)tBu2a und (tBu2P)2PR b, R = Me, Et, nPr, iPr, nBu, PhCH2, CH2CH = CH2, CF3 bei Umsetzungen von Li(THF)2 · [η2-(tBu2P)2P] 2 mit MeCl, MeI, EtCl, EtBr, nPrCl, nPrBr, iPrCl, nBuBr, PhCH2Cl, ClCH2CH = CH2 und CF3Br berichtet. Neben den ylidischen Verbindungen a bilden sich die entsprechenden Triphosphane (tBu2P)2PR b, wobei in THF-Losung die Bildung von a, in Pentan-Losung die von b begunstigt ist. Mit ClCH2CH2 = CH2 bildet sich nur b, mit CF3Br dagegen die Ylide tBu2PP = P(Br)tBu2 und tBu2PPP(CF3)tBu2, aber kein Phosphan b. Das Verhaltnis zwischen a und b wird auch durch die Reaktionstemperatur beeinflust. So bildet 2 mit EtBr in THF bei −70°C die Produkte tBu2PP = P(Et)tBu24a und (tBu2P)2PEt 4 b im Verhaltnis 4:3, bei 20°C 1:1; in Pentan bei −70°C 4a:4b = 1:1, bei 20°C 1:2. 2reagiert nicht mit tBuCl und H2C = CHCl. Die Verbindungen a zersetzen sich bei UV-Bestrahlung oder beim Erwarmen unter Bildung von tBu2PR und der Cyclophosphane (tBu2P)nPn. The Phosphinophosphinidene-phosphoranes tBu2PP = P(R)tBu2 from Li(THF)2[η2-(tBu2P)2P] and Alkyl Halides We report the formation of tBu2PP = P(R)tBu2a and (tBu2)2PR b (with R = Me, Et, nPr, iPr, nBu, PhCH2, H2C = CHCH2 and CF3) reactions of Li(THF)2[η2-(tBu2P)2P] 2 with MeCl, MeI, EtCl, EtBr, nPrCl, nPrBr, iPrCl, nBuBr, PhCH2Cl, H2C = CHCH2Cl or CF3Br. In THF solutions the ylidic compounds a predominate, whereas in pentane the corresponding triphosphanes b are preferrably formed. With ClCH2CH = CH2 only b is produced; CF3Br however yields both tBu2PP = P(Br)tBu2 and tBu2PP = P(CF3)tBu2, but no b. The ratio of a:b is influenced by the reaction temperature, too. The compounds tBu2PP = P(Et)tBu24a and (tBu2P)2PEt 4 b, e. g., are produced in a ratio of 4:3 at −70°C in THF, and 1:1 at 20°C; whereas 1:1 is obtained at −70°C in pentane, and 1:2 at 20°C. Neither tBuCl nor H2C = CHCl react with 2. The compounds a decompose thermally or under UV irradiation forming tBu2PR and the cyclophosphanes (tBu2P)nPn.

The paper presents the mechanical and electronic structure, the basic functions and the operation block diagrams developed for the command and control unit of the PARASURG 9M hybrid parallel robot.

Es wird ein neuer Weg zur Bildung von tBu2PPP(Me)tBu21 und tBu(Me3Si)PPP(Me)tBu22 mitgeteilt, der auf der Umsetzung von LiP[P(tBu)2]25 mit Substitutionsreagenzien (Me2SO4, CH3Cl) basiert. Die Ergebnisse der Kristallstrukturuntersuchung von 1 und 2 werden mitgeteilt und mit denen des tBu2PPP(Br)tBu23 verglichen. Wahrend in 3 der eine Abstand einer Doppelbindung entspricht und der andere einer Einfachbindung (Differenz 12,5 pm) sind die Differenzen der PP-Abstande in 1 und 2 weit geringer, in 1 5,28 pm, in 2 4,68 pm. 1 und 2 kristallisieren beide monoklin in der Raumgruppe P21/n mit vier Formeleinheiten in der Elementarzelle. Bei 2 werden zusatzlich zwei fehlgeordnete Molekule des Losungsmittels Pentan in der Elementarzelle eingebaut. Parameter von 1: a = 884,32(8) pm, b = 1 924,67(25) pm, c = 1 277,07(13) pm, β = 100,816(8)°, 2: a = 1 101,93(12) pm, b = 1 712,46(18) pm, c = 1 395,81(12) pm, β = 111,159(7)°, jeweils bei der Mestemperatur 143 K. Das Gerust der drei P-Atome ist gewinkelt, Winkel in 1 100,95°, in 2 100,29° und in 3 auf 105,77° aufgeweitert. Mit Hilfe von ab initio SCF-Rechnungen werden die Bindungsverhaltnisse im Molekulgerust der drei P-Atome in 1 und 3 diskutiert. Es zeigt sich ein deutlicher Beitrag der ionogenen Struktur R2PP(−)P(+)(X)R2. Die Struktur mit separierten (Teil-)Ladungen wird durch grose, polarisierte Gruppen R wie tBu im Vergleich zur (unpolaren) normalvalenten Verbindung R2PP(X)PR2 stabilisiert. Synthesis and Structure of Phosphinophosphinidene-phosphoranes tBu2PPP(Me)tBu21, tBu(Me3Si)PPP(Me)tBu22, and tBu2PPP(Br)tBu23 A new method for the synthesis of 1 and 2 (Formulae see „Inhaltsubersicht”) is reported based on the reaction of 5 with substitution reagents (Me2SO4 or CH3Cl). The results of the X-ray structure determination of 1 and 2 are given and compared with those of 3. While in 3 one PP distance corresponds to a double bond and the other PP distance to a single bond (difference 12.5 pm) the differences of the PP distances in 1 and 2 are much smaller: 5.28 pm in 1, 4.68 pm in 2. Both 1 and 2 crystallize monoclinic in the space group P21/n (Z = 4). 2 additionally contains two disordered molecules of the solvent pentane in the unit cell. Parameters of 1: a = 884.32(8) pm, b = 1 924.67(25) pm, c = 1 277.07(13) pm, β = 100.816(8)°, and of 2: a = 1 101.93(12) pm, b = 1 712.46(18) pm, c = 1 395.81(12) pm, β = 111.159(7)°, all data collected at 143 K. The skeleton of the three P atoms is bent (PPP angle 100.95° for 1, 100.29° for 2 and 105.77° for 3). Ab initio SCF calculations are used to discuss the bonding situation in the molecular skeleton of the three P atoms of 1 and 3. The results show a significant contribution of the ionic structure R2PP(−)P(+)(X)R2. The structure with (partially) charged P atoms is stabilized by bulky polarizable groups R (as tBu) as compared to the fully covalent structure R2PP(X)PR2.

[iPr2P]2PSiMe31 und [iPr2P]2PLi 2 wurden synthetisiert. Die Umsetzungen von 1 mit CBr4 und von 2 mit 1,2-Dibromethan bzw. MeCl ermoglichen einen Vergleich des Einflusses der iPr- bzw. tBu-Gruppen auf Bildung und Eigenschaften der Ylide R2PPP(X)R2 (R = iPr, tBu; X = Br, Me) bei analogen Reaktionen. Die tBu-Gruppe begunstigt gegenuber der iPr-Gruppe die Ylidbildung. 1 bildet mit CBr4 das iPr2PPP(Br)iPr25 als Nebenprodukt, das sich schon unterhalb −30°C zersetzt. 2 bildet mit 1,2-Dibromethan das Ylid 5 nur in Spuren, aber [(iPr)2P]2PP[P(iPr)2]27 als Hauptprodukt. 2 reagiert mit MeCl zum iPr2PPP(Me)iPr29 und [iPr2P]2PMe 10 im Molverhaltnis 1:1. 9 ist erheblich bestandiger als 5. 7 kristallisiert triklin in P1 (Nr. 2) mit a = 10,813 A, b = 11,967 A, c = 15,362 A, α = 67,90°, β = 71,36°, γ = 64,11°. Die Elementarzelle enthalt zwei Formeleinheiten. [iPr2P]2PSiMe3 and [iPr2P]2PLi – Synthesis and Reactions Structure of [iPr2P]2PP[PiPr2]2 [iPr2P]2PSiMe31 and [iPr2P]2PLi 2 were prepared to investigate the influence of the bulky alkyl groups on formation and properties of the ylides R2PPP(X)R2 (R = iPr, tBu; X = Br, Me) in reactions of 1 with CBr4 and of 2 with 1,2-dibromoethane or MeCl, resp. Compared to the iPr groups the tBu groups favour the formation of ylides. With CBr41 forms iPr2PPP(Br)iPr25 just as a minor product which decomposes already below −30°C. With 1,2-dibromoethane 2 yields only traces of 5 but [iPr2P]PP[P(iPr)2]27 as main product. With MeCl 2 gives iPrPPP(Me)iPr29 and [iPr2P]2PMe 10 in a molar ratio of 1:1. 9 is considerably more stable than 5. 7 crystallizes triclinic in the space group P1 (No. 2) with a = 10.813 A, b = 11.967 A, c = 15.362 A, α = 67.90°, β = 71.36°, γ = 64.11° and two formula units in the unit cell.

Die 800 m lange, in Querrichtung sehr schlanke Schraegkabel-Strassenbruecke wurde auf aussergewoehnliche Windgeschwindigkeiten und starke Boeigkeit bemessen. Sie wurde sowohl fuer den Gebrauchs- als auch fuer den Bruchzustand berechnet, jeweils ueber zeitlich-raeumliche Simulationen des boeigen Windes. Die Windkraft-Charakteristika des Querschnitts wurden aus den statischen Teilmodellversuchen abgeleitet. Fuer den Bruchzustand wurden Theorie-2.-Ordnung-Wirkungen, Nichtlinearitaeten und Schnittkraft-Interaktionen beruecksichtigt. Die Ergebnisse sind statistisch ausgewertet worden. Es ergaben sich spuerbare Kostenersparnisse durch die unmittelbare Berechnung des Bruchzustands im Vergleich zur linearen Extrapolation des Gebrauchszustands. (A*)

Die Umsetzung von (tBu)2PPP(Br)tBu21 mit LiP(SiMe3)22 fuhrt zu den Verbindungen (Me3Si)2PP(SiMe3)24 und P[P(tBu)2]2P(SiMe3)25, mit LiPMe22 entsprechend zu P2Me46 und P[P(tBu)2]2PMe27. Mit LiMe bildet 1 das Ylid tBu2PPP(Me)tBu214 (Hauptprodukt) neben [tBu2P]2PMe 15. Bei Umsetzung von 1 mit tBuLi is [tBu2P]2PH 11 Hauptprodukt, und es bildet sich tBu2PPP(R)tBu221. Die Umsetzung von 1 mit nBuLi fuhrt zum [tBu2P]2PnBu 17 (Hauptprodukt) neben tBu2PPP(nBu)tBu222. Der Verlauf der Umsetzungen wird beschrieben. Reactions of (tBu)2PPP(Br)tBu2 with LiP(SiMe3)2, LiPMe2 and LiMe, LitBu and LinBu The reactions of (tBu)2PPP(Br)tBu21 with LiP(SiMe3)22 yield (Me3Si)2PP(SiMe3)24 and P[P(tBu)2]2P(SiMe3)25, whereas 1 with LiPMe22 yields P2Me46 and P[(tBu)2]2PMe27. 1 with LiMe yields the ylid tBu2PPP(Me)tBu2 (main product) and [tBu2P]2PMe 15. In the reaction of 1 with tBuLi [tBu2P]2PH 11 is the main product and also tBuPPP(R)tBu221 is formed. The reaction of 1 with nBuLi leads to [tBu2P]2PnBu 17 (main product) and tBu2PPP(nBu)tBu222 (secondary product).

Our aim was to obtain an objective evaluation of the airway before and after glottis-dilating operations utilizing lung function tests. The charts of 109 patients who underwent either reversible or irreversible glottis-dilating operations by Lichtenberger were reviewed. 64 non-selected cases of these patients, all with irreversible glottis-dilating operations, were studied. Lung function tests that were performed were body-pletysmography, forced inspiratory volume (FIV1), forced expiratory volume (FEV1), peak inspiratory flow rate (PIF), peak expiratory flow rate (PEF) and resistance of the airways (RAW). The FEV1, FIV1, PEF and PIF all improved following irreversible glottis-dilating operations. The RAW was remarkably decreased post-operatively as compared to pre-operatively. In conclusion, the airways of patients undergoing irreversible glottis-dilation operations improved moderately to well following such surgeries. Lung function tests are an objective means of evaluating the airway before and after surgery.