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Phenotypic variability in cell populations can be described through population balance models (PBM). In this paper, the simulation of cell PBMs via two different methods is compared. We compare the cell average technique (CAT) with the recently introduced numerical Gaussian processes (GPs). While the CAT discretises the PBM in the individual variables, i.e. in the cellular properties, numerical GPs circumvent this discretisation. Numerical GPs are a probabilistic machine-learning method that additionally provides uncertainty quantification. Using two simulation case studies, we compare both methods with regards to computational load, accuracy, and implementation effort. In one of the two considered case studies, numerical GPs are inferior to the CAT. Nonetheless, they are an attractive option when uncertainty quantification is very much required, such as in a subsequent state estimation for PBMs.

Past research has neglected the question of whether different exchange mechanisms and consumption or service contexts (CSCs) in the sharing economy may lead to different outcomes. The authors develop a novel theoretical framework that proposes that willingness to participate in the sharing economy will be lower if exchange mechanisms and CSCs do not match—that is, if monetary/social exchange mechanisms are applied in hedonic/utilitarian CSCs, taking into account the moderating role of materialism. Moreover, the authors propose that in the sharing economy, monetary exchanges may cause a crowding-out of prosocial behaviors and that this effect will be especially pronounced for highly materialistic individuals. They test their hypothesized framework in three experimental studies that support the theorizing and provide results with important implications for the design of sharing economy offers as well as for society.

Pelvic-ring-injuries are bony and/or ligamentous disruptions that might lead to pelvic instabilities and asymmetries. For surgical treatment, knowledge of the different possible approaches and stabilization-techniques is essential. From 2003 to 2017, we analyzed all complications in operative and non-operative treatment of pelvic-ring-injuries in our institution. Besides complication rates, we describe the reachable anatomical structures for different surgical approaches to the pelvic-ring focusing on strategies to reduce surgical complications. Of 1848 patients with a pelvic fracture, 1463 patients had a pelvic-ring-fracture. We found an overall complication-rate of 14.4%. For reducing approach-related morbidity, preoperative planning and knowledge of approach-related complications is important.

The ability to perform at a high level, even when the task at hand is interrupted by an unrelated secondary task, is central to human information processing. Executive control processes, in particular the reallocation of attentional resources, are crucial for coping with interruptions. Although the age-related decline in cognitive control functions is well described, the consequences of such changes for the ability to deal with interruptions are as of yet unclear. In the present study, we examined behavioral performance as well as electrophysiological parameters associated with executive control processes in older and younger participants using a nested task design: In one third of all trials, an ongoing working memory task was interrupted by a math task. We found that the impact of interruptions on primary task performance was more severe in the older age group. In the EEG, older adults showed stronger frontal midline theta activation and fronto-parietal connectivity in the theta range in response to the cue indicating the relevant attentional set. Younger participants, on the other hand, showed distinct and specific increases in cognitive control as indexed by frontal midline theta in response to the stimulus signaling an upcoming interruption. Overall, the results reveal strategic differences between the age groups, as older participants seem to prioritize the primary task more strongly. The data furthermore indicate that the combination of a rapid succession of events and the decreased ability to shift executive resources renders older adults’ performance particularly vulnerable to the occurrence of interruptions.

This chronosequential study focuses on the vegetation succession, Luvisol pedogenesis, and long-term carbon dynamics during post-agricultural restoration in the temperate broad-leaved forest of European Russia. The study comprises three chronosequences of 37 years (North), 120 years (Middle), and 42 years (South) to cover climatic differences within the study area. The sites of each catena were mostly comparable in terms of climate, soil texture, and land history, but the duration of agricultural abandonment differed between sites. Plant succession developed via a birch forest or a pear-ash woodland to a birch-oak forest with Aegopodium podagraria after 120 years, which indicates the plant association is near to a climax oak forest. Former homogenous plow horizons formed a new morphological stratification similar to natural Luvisols, due to the formation of a well rooted Ah horizon and an O horizon of mull; a change in soil structure from coarse blocky to granular; and decreasing bulk densities. However, plow features were identified even after 120 years of Luvisols restoration. During restoration, the former plow horizons showed minor changes of pH 5.4–5.6 (CaCl2). However, a slightly increased pH value within the newly developed Ah and O horizons induced a new pH stratification of the former plow horizon, approaching the natural soils. Compared to the former plow horizons below, soil organic carbon (SOC) and plant available nutrients (P, K) enrichment was observed within the newly developed Ah horizons. The SOC stocks of the 5 cm mineral topsoil increased from 0.8 to 1.7 kg m−2 (North), from 1.3 to 1.7 kg m−2 (Middle), and from 1.4 to 2.3 kg m−2 (South) during restoration. The surface organic layers showed SOC stocks of 0.1–0.2 kg m−2. However, the levels of the near-natural soils were not reached after 37 years (North) and 42 years (South) of restoration. The model predicted a recovery time of about 150 years to achieve a comparatively steady state. A negative effect of mowing was observed for the modelled SOC accumulation. Despite all these alterations, the study showed no full restoration for many parameters within the chronosequential timescale of 120 years.

Displaced acetabular fractures usually require open surgical approaches. Aim of this cadaver study was to evaluate a laparoscopic approach to prepare the anterior acetabular column and the quadrilateral plate in analogy to the laparoscopic pelvic lymphadenectomy. The laparoscopic preparation and anatomy is presented and illustrated step by step in a human cadaver followed by a modular plate osteosynthesis of the anterior column involving the quadrilateral plate is performed via a minimally invasive approach using standard laparoscopic instruments. In conclusion we could demonstrate that the laparoscopic preperitoneal preparation of the acetabulum according to the laparoscopic pelvic lymphadenectomy provides more free range for the surgical instruments compared to a previously described total extraperitoneal approach. The development of specific reduction tools and implants is under investigation. Until then, at least the laparoscopic preparation could be introduced in the clinical setting in the near future. Type of study Technical Note–Cadaver Study.

Displaced acetabular fractures usually require open surgical approaches. Aim of this cadaver study was to evaluate a laparoscopic approach to prepare the anterior acetabular column and the quadrilateral plate in analogy to the laparoscopic pelvic lymphadenectomy. The laparoscopic preparation and anatomy is presented and illustrated step by step in a human cadaver followed by a modular plate osteosynthesis of the anterior column involving the quadrilateral plate is performed via a minimally invasive approach using standard laparoscopic instruments. In conclusion we could demonstrate that the laparoscopic preperitoneal preparation of the acetabulum according to the laparoscopic pelvic lymphadenectomy provides more free range for the surgical instruments compared to a previously described total extraperitoneal approach. The development of specific reduction tools and implants is under investigation. Until then, at least the laparoscopic preparation could be introduced in the clinical setting in the near future. Type of study Technical note – Cadaver study.

In recent years, live streaming websites have evolved into popular meeting places for people interested in video games. While earlier research found that the joint playing of online video games might foster social capital, watching an individual streamer playing seems to be a non-social experience. However, the corresponding live chat might offer the chance to interact and bond with like-minded people. The present study investigates the influence of physical proximity, social proximity and familiarity on communication frequency and self-disclosure of live stream viewers. Moreover, we examine the role of parasocial interaction with the streamer, and analyze whether these factors influence the formation of bridging and bonding social capital. A total of 164 live streaming website users were recruited for an online survey. A structural path model yielded several significant relations: In particular, regular website visits and assuming the role of a moderator facilitate the formation of social capital. Interaction with the streamer emerged as a further influencing factor. The results demonstrate that live streams are more than a passive leisure activity, and instead offer the opportunity to interact and form weak and strong social ties.

The right cerebral hemisphere (RH) appears to be more effective in representing visual objects as distinct exemplars than the left hemisphere (LH) which is presumably biased towards coding objects at the level of abstract prototypes. As of yet, relatively little is known about the role that asymmetries in exemplar-specificity play at the level of explicit memory retrieval. In the present study, we addressed this issue by examining hemispheric asymmetries in the putative event-related potential (ERP) correlates of familiarity (FN400) and recollection (LPC). In an incidental study phase, pictures of familiar objects were presented centrally. At test, participants performed a memory inclusion task on identical repetitions and different exemplars of study items as well as new items which were presented in only one visual hemifield using the divided visual field technique. With respect to familiarity, we observed exemplar-specific FN400 old/new effects that were more pronounced for identical repetitions than different exemplars, irrespective of the hemisphere governing initial stimulus processing. In contrast, LPC old/new effects were subject to some hemispheric asymmetries indicating that exemplar-specific recollection was more extensive in the RH than in the LH. This further corroborates the idea that hemispheric asymmetries should not be generalized but need to be distinguished not only in different domains but also at different levels of processing.

Immune cells regulate a hypertonic microenvironment in the skin; however, the biological advantage of increased skin Na(+) concentrations is unknown. We found that Na(+) accumulated at the site of bacterial skin infections in humans and in mice. We used the protozoan parasite Leishmania major as a model of skin-prone macrophage infection to test the hypothesis that skin-Na(+) storage facilitates antimicrobial host defense. Activation of macrophages in the presence of high NaCl concentrations modified epigenetic markers and enhanced p38 mitogen-activated protein kinase (p38/MAPK)-dependent nuclear factor of activated T cells 5 (NFAT5) activation. This high-salt response resulted in elevated type-2 nitric oxide synthase (Nos2)-dependent NO production and improved Leishmania major control. Finally, we found that increasing Na(+) content in the skin by a high-salt diet boosted activation of macrophages in a Nfat5-dependent manner and promoted cutaneous antimicrobial defense. We suggest that the hypertonic microenvironment could serve as a barrier to infection.

Lower urinary tract infections are among the most common human bacterial infections, but extension to the kidneys is rare. This has been attributed to mechanical forces, such as urine flow, that prevent the ascent of bladder microbes. Here, we show that the regional hypersalinity, required for the kidney's urine-concentrating function, instructs epithelial cells to produce chemokines that localize monocyte-derived mononuclear phagocytes (MNPs) to the medulla. This hypersaline environment also increases the intrinsic bactericidal and neutrophil chemotactic activities of MNPs to generate a zone of defense. Because MNP positioning and function are dynamically regulated by the renal salt gradient, we find that patients with urinary concentrating defects are susceptible to kidney infection. Our work reveals a critical accessory role for the homeostatic function of a vital organ in optimizing tissue defense.

Zusammenfassung Leitsymptom sind Sensibilitatsstorungen in einer Strumpf- Handschuh Verteilung und motorische Symptome mit abgeschwachten bis ausgefallenen Muskeleigenreflexen bis zu Paresen. Die neurophysiologischen Untersuchungen sind der Goldstandard in der diagnostischen Sicherung. Die Unterscheidung zwischen axonaler und demyelinisierender Neuropathie ist Wegweisend zur Ursache.

Zusammenfassung Hintergrund Der Bewegungsapparat paralympischer Athleten ist behinderungsbedingt besonderen Belastungen ausgesetzt. Die zunehmende Professionalisierung des paralympischen Sports hat zu stetig wachsenden Trainingsumfangen und Wettkampfbelastungen gefuhrt. Diese Entwicklung beinhaltet das Risiko eines Missverhaltnisses zwischen korperlicher Belastung und Regeneration und fuhrt mutmaslich zu einer Zunahme von Uberlastungsbeschwerden insbesondere zum Saisonhohepunkt. Das Ziel der vorliegenden Arbeit war, die Haufigkeit und Schwere der muskuloskeletalen Erkrankungen deutscher Paralympioniken zu dokumentieren und diese sportart- und behinderungsspezifisch zu analysieren. Material und Methoden Wahrend der paralympischen Sommerspiele 2012 wurden alle Erkrankungen und Verletzungen deutscher Athleten standardisiert dokumentiert (Zeitpunkt und Schwere der Erkrankung, Diagnose, Beeintrachtigung der Trainings- und Wettkampffahigkeit und die getroffenen Behandlungsmasnahmen). Nach Abschluss der In-Competition-Period wurden die Daten anonymisiert in eine Datenbank ubertragen und auf mogliche Unterschiede zwischen den Startklassen und Sportarten analysiert. Ergebnisse Von den 150 behinderten und 3 nicht-behinderten (Guides) paralympischen Athleten (n = 153, Alter ∅ 33 Jahre) wurden 140 Athleten (Alter ∅ 33 Jahre) aufgrund orthopadisch-traumatologischer Krankheitsbilder behandelt. Insgesamt 201 Beschwerden (1,4 / verletzten Sportler) fuhrten zur Konsultation des medizinischen Teams. Die haufigsten Beschwerden waren muskulare Uberlastungen (n = 105), Tendinopathien (n = 14), unspezifische Ruckenschmerzen (n = 14), Wirbelblockierungen (n = 11), offene Hautlasionen (n = 10), Prelllungen (n = 6) und Distorsionen (n = 8). Wirbelsaule und obere Extremitat waren in 37,6% betroffen, die untere Extremitat in 21,5%. Die Sporttauglichkeit war mehrheitlich (77%) erhalten, bei 43 Athleten (20%) eingeschrankt und nur bei 4 Athleten aufgehoben. 12,5% der Beschwerden waren vor der Anreise nach London aufgetreten, 77% wahrend der Paralympics. Die Verletzungshaufigkeit war im Rollstuhlbasketball und Rudern im Vergleich zu den ubrigen Sportarten erhoht (1,6 vs. 1,3 Verletzungen/Sportler). Eine erhohte Verletzungshaufigkeit von sehbehinderten Athleten konnte nicht festgestellt werden. Schlussfolgerungen Paralympische Athleten sind durchschnittlich 7 Jahre alter als nicht-behinderte Olympioniken. Ein Altersunterschied der verletzten und unverletzten Athleten lies sich nicht nachweisen. Deutsche Athleten wurden haufiger medizinisch behandelt als der internationale Durchschnitt. Im Gegensatz zu nicht-behinderten Athleten treten Verletzungen/Beschwerden der Wirbelsaule und der oberen Extremitaten gehauft auf. Die Verletzungsrate war insbesondere bei Rollstuhlbasketballerinnen erhoht, eine erhohte Verletzungsanfalligkeit sehbehinderter Athleten lies sich nicht verzeichnen. Die vorgelegten Daten sollten auch als Grundlage fur die Erstellung sportartspezifischer Praventionsprogramme dienen.

Cerebellar mutism occurs in about 25% of children following posterior fossa tumor surgery. It is usually accompanied by other neurological and behavioral disturbances. Mutism is transient in nature lasting several days to months and is frequently followed by dysarthria. In addition, impairment of language and other neuropsychological functions can be found after long term follow up in the majority of patients. The pathophysiological background of mutism may be higher speech dysfunction mediated by crossed cerebello-cerebral diaschisis which is frequently found during the mute period. Foremost injury to the bilateral dentatothalamocortical tract appears to be critical for the development of cerebello-cerebral diaschisis and subsequent mutism. Direct cerebellar injury is the likely reason for persisting deficits after the mute period. Minimization of injury to the dentatothalamocortical tract during surgery may be promising in the prevention of mutism. While there is no established treatment of mutism, early speech and rehabilitation therapy is recommended.

According to most experts, integrated and sustainable solid waste management should not only be given top priority, but must go beyond technical aspects to include various key elements of sustainability to ensure success of any solid waste project. Aside from project sustainable impacts, the overall enabling environment is the key feature determining performance and success of an integrated and affordable solid waste system. This paper describes a project-specific approach to assess typical success or failure factors. A questionnaire-based assessment method covers issues of: (i) social mobilisation and acceptance (social element), (ii) stakeholder, legal and institutional arrangements comprising roles, responsibilities and management functions (institutional element); (iii) financial and operational requirements, as well as cost recovery mechanisms (economic element). The Gianyar Waste Recovery Project in Bali, Indonesia was analysed using this integrated assessment method. The results clearly identified chief characteristics, key factors to consider when planning country wide replication but also major barriers and obstacles which must be overcome to ensure project sustainability. The Gianyar project consists of a composting unit processing 60 tons of municipal waste per day from 500,000 inhabitants, including manual waste segregation and subsequent composting of the biodegradable organic fraction.

During antidiuresis, cell survival in the renal medulla requires cyclooxygenase-2 (COX-2) activity. We have recently found that prostaglandin E2 (PGE 2 ) promotes cell survival by phosphorylation and, hence, inactivation of the pro-apoptotic protein Bad during hypertonic stress in Madin-Darby canine kidney (MDCK) cells in vitro . Here we determine the role of COX-2-derived PGE 2 on phosphorylation of Bad and medullary apoptosis in vivo using COX-2-deficient mice. Both wild-type and COX-2-knockout mice constitutively expressed Bad in tubular epithelial cells of the renal medulla. Dehydration caused a robust increase in papillary COX-2 expression, PGE 2 excretion, and Bad phosphorylation in wild-type, but not in the knockout mice. The abundance of cleaved caspase-3, a marker of apoptosis, was significantly higher in papillary homogenates, especially in tubular epithelial cells of the knockout mice. Knockdown of Bad in MDCK cells decreased tonicity-induced caspase-3 activation. Furthermore, the addition of PGE 2 to cells with knockdown of Bad had no effect on caspase-3 activation; however, PGE 2 caused phosphorylation of Bad and substantially improved cell survival in mock-transfected cells. Thus, tonicity-induced COX-2 expression and PGE 2 synthesis in the renal medulla entails phosphorylation and inactivation of the pro-apoptotic protein Bad, thereby counteracting apoptosis in renal medullary epithelial cells.

The deep cerebellar nuclei (DCN) are a key element of the cortico-cerebellar loop. Because of their small size and functional diversity, it is difficult to study them using magnetic resonance imaging (MRI). To overcome these difficulties, we present here three related methodological advances. First, we used susceptibility-weighted imaging (SWI) at a high-field strength (7T) to identify the dentate, globose, emboliform and fastigial nucleus in 23 human participants. Due to their high iron content, the DCN are visible as hypo-intensities. Secondly, we generated probabilistic maps of the deep cerebellar nuclei in MNI space using a number of common normalization techniques. These maps can serve as a guide to the average location of the DCN, and are integrated into an existing probabilistic atlas of the human cerebellum (Diedrichsen et al., 2009). The maps also quantify the variability of the anatomical location of the deep cerebellar nuclei after normalization. Our results indicate that existing normalization techniques do not provide satisfactory overlap to analyze the functional specialization within the DCN. We therefore thirdly propose a ROI-driven normalization technique that utilizes both information from a T1-weighted image and the hypo-intensity from a T2*-weighted or SWI image to ensure overlap of the nuclei. These techniques will promote the study of the functional specialization of subregions of the DCN using MRI.

The otherwise robust behavioral semantic priming effect is reduced to the point of being absent when a letter search has to be performed on the prime word. As a result the automaticity of semantic activation has been called into question. It is unclear, however, in how far automatic processes are even measurable in the letter search priming paradigm as the prime task necessitates a long prime-probe stimulus-onset asynchrony (SOA). In a modified procedure, a short SOA can be realized by delaying the prime task response until after participants have made a lexical decision on the probe. While the absence of lexical decision priming has already been demonstrated in this design it seems premature to draw any definite conclusions from this purely behavioral result since event related potential (ERP) measures have been shown to be a more sensitive index of semantic activation. Using the modified paradigm we thus recorded ERP in addition to lexical decision times. Stimuli were presented at two different SOAs (240 ms vs. 840 ms) and participants performed either a grammatical discrimination (Experiment 1) or a letter search (Experiment 2) on the prime. Irrespective of prime task, the modulation of the N400, the ERP correlate of semantic activation, provided clear-cut evidence of semantic processing at the short SOA. Implications for theories of semantic activation as well as the constraints of the delayed prime task procedure are discussed.

Background The secure sealing of natural orifice transluminal endoscopic surgery (NOTES) approaches to the abdominal cavity is a problem that has not been solved. The feasibility of closing iatrogenic endoscopic GI-tract perforations by using a new over-the-scope clip was recently described. Objective To demonstrate the feasibility of endoscopic closure of transgastric NOTES approaches with a novel clip system. Design Acute nonsurvival animal study (porcine model; n=9). Interventions Transgastric approaches were performed by using a needle-knife and balloon dilation. After abdominopelvic exploration, the transgastric approaches were closed by using the OTSC clipping system with suction. The procedure was performed under laparoscopic visualization. Results Gastrotomy lesions could primarily be closed in 8 cases. However, the laparoscopic control indicated that the clip adaptation of the wound margins was not completely airtight under maximum insufflation of the stomach in 4 of 9 cases. Limitation Nonsurvival animal study. Conclusions Sufficient closure of transgastric NOTES approaches is feasible when using the OTSC system. When considering our clinical experience, the OTSC system was shown to be an uncomplicated and secure sealing technique in human beings.

Summary Measured alone or combined with other serum markers, hyaluronic acid (HA) has been reported as being relevant for predicting liver fibrosis in patients with chronic liver disease and is proposed as a non-invasive alternative to liver biopsy. However, until now, only manual assays have been available. The latex agglutination method (HA detection reagent, Latex method, Wako, Osaka, Japan) using recombinant hyaluronic acid binding protein (rHABP) and latex sensitized with anti-HABP monoclonal antibody was evaluated using an Olympus AU640 analyzer (Tokyo, Japan). Within-run imprecision was between 1 and 2.2%. Between-run imprecision was between 2 and 4%. Correlation with Corgenix HA-Test®was y = 0.987 × − 0.871 (r = 0.995). No accuracy problem was detected. Serum or heparinized plasma can be used equally. The detection limit was estimated as 1.5 μg/L. A totally automated serum HA assay is now available for clinical chemists so that its determination in assessing liver fibrosis, particularly in composite indices can be largely proposed.

This paper explores whether spatial variation in the biodiversity values of vertebrates and plants (species richness, range-size rarity and number or proportion of IUCN Red Listed threatened species) of three African tropical mountain ranges (Eastern Arc, Albertine Rift and Cameroon-Nigeria mountains within the Biafran Forests and Highlands) co-vary with proxy measures of threat (human population density and human infrastructure). We find that species richness, range-size rarity, and threatened species scores are all significantly higher in these three tropical African mountain ranges than across the rest of sub-Saharan Africa. When compared with the rest of sub-Saharan Africa, human population density is only significantly higher in the Albertine Rift mountains, whereas human infrastructure is only significantly higher in the Albertine Rift and the Cameroon-Nigeria mountains. Statistically there are strong positive correlations between human density and species richness, endemism and density or proportion of threatened species across the three tropical African mountain ranges, and all of sub-Saharan Africa. Kendall partial rank-order correlation shows that across the African tropical mountains human population density, but not human infrastructure, best correlates with biodiversity values. This is not the case across all of sub-Saharan Africa where human density and human infrastructure both correlate almost equally well with biodiversity values. The primary conservation challenge in the African tropical mountains is a fairly dense and poor rural population that is reliant on farming for their livelihood. Conservation strategies have to address agricultural production and expansion, in some cases across the boundaries and into existing reserves. Strategies also have to maintain, or finalise, an adequate protected area network. Such strategies cannot be implemented in conflict with the local population, but have to find ways to provide benefits to the people living adjacent to the remaining forested areas, in return for their assistance in conserving the forest habitats, their biodiversity, and their ecosystem functions.

Insbesondere beim Kinderschuh kommt der optimalen Anpassung hinsichtlich Erkrankungen des Stutz- und Bewegungsapparates im Erwachsenenleben grose Bedeutung zu. Es wird ein Verfahren mittels Computertomographie zur zerstorungsfreien Prufung beschrieben, bei dem der zu prufende Schuh luckenlos mittels Computertomographie (CT) untersucht wird. Mit Hilfe von Nachverarbeitungsprogrammen (MATLAB) und 3DSoftware (AMIRA) werden die Daten analysiert und die fur den Konstrukteur masgeblichen Mase automatisch bestimmt. Durch Vergleich des fur die Herstellung des Leistens verwendeten CAD-Datensatzes mit dem computertomographisch gewonnenen Binnenraum eines darauf aufgebauten Schuhmodells konnen Abweichungen sichtbar gemacht werden. Messungen mit dem beschriebenen Verfahren zeigten, dass die Innenraume von Schuhen zerstorungsfrei sichtbar gemacht werden konnen. Beliebige Punkte des Schuhinnenraums konnten bestimmt, Strecken vermessen und Volumen berechnet werden. Es konnten Grosen bestimmt werden, die bei der Schuhkonstruktion eine wichtige Rolle spielen und dementsprechend sich auch im fertigen Schuh wieder finden sollten (Brandsohle). Es war aber auch moglich Mase zu ermitteln, die fusrelevanter sind wie z.B. die tatsachliche Lange und Breite des Schuhinnenraums. Hierfur wurde der Parameter „+1 cm“ eingefuhrt. Dieser beinhaltet z. B. die Lange und Breite des Schuhinnenraums in 1 cm Hohe uber der Brandsohle und berucksichtigt die Lage der tatsachlichen Lange und Breite des Fuses.

The perselenoborates RbBSe{sub 3} and CsBSe{sub 3} can be prepared from the metal selenides, amorphous boron, and selenium, in the case of TlBSe{sub 3} directly from the elements. The solid-state reactions were carried out in evacuated carbon-coated silica tubes at high temperatures. Single-crystal X-ray data were used to determine the crystal structures. Both alkali metal perselenoborates RbBSe{sub 3} and CsBSe{sub 3} crystallize in the monoclinic space group P2{sub 1}/c (RbBSe{sub 3}: a=7.279(2) {angstrom}, b=12.385(3) {angstrom}, c=6.169(2) {angstrom}, {beta}=105.67(3){degree}, Z=4, R1=0.0373, and wR2(F{sup 2})=0.1000; CsBSe{sub 3}: a=7.570(2) {angstrom}, b=12.791(4) {angstrom}, c=6.171(2) {angstrom}, {beta}=107.09(2){degree}, Z=4, R1=0.0332, and wR2(F{sup 2})=0.0751), while the thallium perselenoborate TlBSe{sub 3} crystallizes in the acentric monoclinic space group Ia (alternative setting to Cc) with the lattice constants a=6.166(2) {angstrom}, b=12.109(2) {angstrom}, c=7.031(2) {angstrom}, {beta}=113.88(3){degree}, Z=4, R1=0. 0423, and wR2(F{sup 2})=0.1157. All three compounds contain polymeric anionic chains of composition ([BSe{sub 3}]{sup {minus}}){sub n} formed by spirocyclically fused nonplanar five-membered B{sub 2}Se{sub 3} rings in which the boron atoms are in a tetrahedral BSe{sub 4} coordination. Vibrational spectra of the new compounds were measured and X-ray powder patterns are reported.

Gas boronizing was performed at low pressure (100–10 000 Pa) with and without plasma assistance using organoboranes as precursors and hydrogen and argon as carrier gases. The influence of total pressure, boronizing time and both precursor flow rate and hydrogen flow rate on the formation of the boride layer on three steels, 42 CrMo 4 (AISI 4140), C 45 (AISI C1043) and a low carbon steel was investigated. The boride layers were characterized using glow discharge optical emission spectroscopy, X-ray diffractometry, optical microscopy and the pin-on-disc test. With an appropriate choice of process parameters single-phased iron boride layers up to 10 μm of type Fe2B were generated on steel 42 CrMo 4 (AISI 4140) using a borane triethylamine complex as a precursor for gas boronizing and trimethylborate for plasma-assisted boronizing. Carbon was determined to be barely incorporated into the boride layers. First wear tests resulted in a significant wear reduction of plasma-boronized samples compared to untreated samples.

In point-resolved spectroscopy (PRESS), fast echo-time-dependent signal modulations of the multiplets of weakly coupled homonuclear spin systems occur. They are caused by polarization-transfer effects that are explained by calculations with the product-operator formalism. The impact of slice profiles and transmitter adjustment and the difference of the polarization-transfer effects between AX and AX3 systems are explained. Experiments with echo-time variation were performed with slice-selective pulses of different quality of profile. Experiments were carried out with a solution of calcium lactate in a 1.5 T Siemens whole-body imager. The experimental results confirm the theoretical calculations. It is stated that in localized double-spin-echo spectroscopy, especially at echo times of TE = 2/J, the polarization-transfer effects must be considered. This knowledge is important in lactate spectroscopy in vivo, where the assumptions for 2/J range between 270 and 290 ms, leading to different signal intensities of lactate in PRESS spectra.