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lovo-cel (bb1111; LentiGlobin for sickle cell disease [SCD]) gene therapy (GT) comprises autologous transplantation of hematopoietic stem and progenitor cells transduced with the BB305 lentiviral vector encoding a modified β-globin gene (β

Patient-derived cancer xenografts (PDX) are widely used to identify and evaluate novel therapeutic targets, and to test therapeutic approaches in preclinical mouse avatar trials. Despite their widespread use, potential caveats of PDX models remain considerably underappreciated. Here, we demonstrate that EBV-associated B-lymphoproliferations frequently develop following xenotransplantation of human colorectal and pancreatic carcinomas in highly immunodeficient NOD.Cg-Prkdcscid Il2rgtm1Wjl /SzJ (NSG) mice (18/47 and 4/37 mice, respectively), and in derived cell cultures in vitro. Strikingly, even PDX with carcinoma histology can host scarce EBV-infected B-lymphocytes that can fully overgrow carcinoma cells during serial passaging in vitro and in vivo. As serial xenografting is crucial to expand primary tumor tissue for biobanks and cohorts for preclinical mouse avatar trials, the emerging dominance of B-lymphoproliferations in serial PDX represents a serious confounding factor in these models. Consequently, repeated phenotypic assessments of serial PDX are mandatory at each expansion step to verify "bona fide" carcinoma xenografts.

Background Fasciocutaneous flaps supplied by discrete perforator arteries can be raised in numerous parts of the human body and are routinely used in plastic surgery. The aim of this anatomical investigation was to provide a description of the vascular supply of the medial upper arm, to localize and measure the perforator arteries and to define potential perforator flap dimensions in pendency of individual anatomical conditions. Material and Methods A total of 20 upper limbs from 11 fresh cadavers were examined. The brachial arteries were exposed and the medial perforator arteries selectively injected with methylene blue and india ink in an alternating sequence. The size of the angiosomes, the diameter and length of the perforators' pedicles and distances between the arteries and the medial epicondyle and apex of the axilla respectively were measured. Results On average, 4.55 ± 1.47 perforating arteries arose from the brachial artery and it's medial off branching arteries. Their mean diameter was 0.68 ± 0.27 mm and their pedicles had an average length of 3.62 ± 1.61 cm measured from suprafascial until arborisation. In 80% the first proximal perforator was present in an area of 4 cm radius at centre coordinates of (20/2). A constant distal perforator was found within a circle of 3 cm radius, of which the centre had the coordinates (8/1). The average size of the angiosomes was 121.1 ± 58.5 cm2. Direct branches of the brachial artery feed circular shaped vascular territories, whereas superior ulnar collateral arteries (SUCAs) feed oblong shaped territories. Conclusion This anatomical study provides valuable data of the medial arm flap in order to be applied clinically. © 2016 Wiley Periodicals, Inc.

Phenol is an omnipresent compound in various situations. Its acute toxicity makes alternative tracing methods desirable. Highly potent affinity materials based on polyvinyl pyridine allow an efficient tracing of this particular airborne compound. Their performance over, for example, benzene is tremendously superior. In combination with a simple cyclodextrin derivative an array allows differentiation among such aromatic competitors. Owing to the high affinity of these polymers for phenol, quartz microbalance-based tracing is able to detect phenol below the parts per million range. This was previously not possible with other affinity materials.

Analyses of the regulatory T (Treg) cell TCR repertoire should help elucidate the nature and diversity of their cognate antigens and thus how Treg cells protect us from autoimmune diseases. We earlier identified CD44(hi) CD62L(low) activated/memory (am) Treg cells as a Treg-cell subset with a high turnover and possible self-specificity. We now report that amTreg cells are predominantly distributed in lymph nodes (LNs) draining deep tissues. Multivariate analyses of CDR3 spectratyping first revealed that amTreg TCR repertoire is different from that of naive Treg cells (nTreg cells) and effector T (Teff) cells. Furthermore, in deep- versus superficial LNs, TCR-β deep sequencing further revealed diversified nTreg-cell and amTreg-cell repertoires, although twofold less diverse than that of Teff cells, and with repertoire richness significantly lower in deep-LN versus superficial-LN Treg cells. Importantly, expanded clonotypes were mostly detected in deep-LN amTreg cells, some accounting for 20% of the repertoire. Strikingly, these clonotypes were absent from nTreg cells, but found at low frequency in Teff cells. Our results, obtained in nonmanipulated mice, indicate different antigenic targets for naive and amTreg cells and that amTreg cells are self-specific. The data we present are consistent with an instructive component in Treg-cell differentiation.

Introduction: This diffusion tensor magnetic resonance imaging (DTI) study aimed to clarify the relationship of peripheral nerves and soft tissue tumors (STTs) in 3D to optimize subsequent treatment. Methods: Twenty-six consecutive STT patients (histologically malignant, n = 10; intermediate, n = 3; and benign, n = 13) underwent 3-Tesla MRI using an echoplanar DTI sequence. Deterministic tractography was performed. Fractional anisotropy (FA) values were measured within peritumoral and distant regions of interest. Results: Tractography depicted the 3D course of the sciatic (n = 12), femoral (n = 2), tibial (n = 7), fibular (n = 2), median (n = 1), musculocutaneous (n = 1), and ulnar (n = 1) nerves in a regular (n = 8 of 18, 44.4%) or thinned (n = 7 of 18, 38.9%) fashion. The lowest peritumoral FA values, abrupt thinning, and/or complete discontinuity of trajectories were found in 2 cases with histologically proven tumoral nerve infiltration. Conclusions: DTI clarifies the 3D topography between major peripheral nerves and STTs and may be helpful in the assessment of peripheral nerve infiltration by malignant tumors. Muscle Nerve 51: 338–345, 2015

Metoidioplasty represents a viable option for female-to-male transsexual patients seeking gender reassignment surgery. The aim of this procedure is to create a microphallus with lengthening of the urethra to the tip of the hypertrophied and released clitoris. However, fistula formation and urethral obstruction might occur in the long term and reconstruction represents a challenging problem in this setting. In this report, we present the tubed superficial inferior epigastric artery perforator island flap as an option for urethral reconstruction after failed metoidioplasty in a female-to-male transsexual patient. In a 26-year-old transsexual patient a combination of urethral fistula, urethral stenosis, and disintegrated distal neourethra had developed as a consequence of postoperative hematoma formation. Metoidioplasty was reconstructed by means of a tubed, pedicled superficial inferior epigastric artery perforator flap from the left lower abdomen. The long-term result was stable with pleasing genital appearance, adequate functional outcome, and satisfactory donor site morbidity. In our opinion, this procedure may represent a viable alternative for urethral reconstruction in thin patients.

To achieve specific cell targeting by various receptors for oligosaccharides or antibodies, a carrier must not be taken up by any of the very many different cells and needs functional groups prone to clean conjugation chemistry to derive well-defined structures with a high biological specificity. A polymeric nanocarrier is presented that consists of a cylindrical brush polymer with poly-2-oxazoline side chains carrying an azide functional group on each of the many side chain ends. After click conjugation of dye and an anti-DEC205 antibody to the periphery of the cylindrical brush polymer, antibody-mediated specific binding and uptake into DEC205(+) -positive mouse bone marrow-derived dendritic cells (BMDC) was observed, whereas binding and uptake by DEC205(-) negative BMDC and non-DC was essentially absent. Additional conjugation of an antigen peptide yielded a multifunctional polymer structure with a much stronger antigen-specific T-cell stimulatory capacity of pretreated BMDC than application of antigen or polymer-antigen conjugate.

A high-molar-mass cylindrical brush polymer with a main chain degree of polymerization of Pw = 1047 is synthesized by free-radical polymerization of a poly-2-isopropyloxazoline macromonomer with Pn = 28. The polymerization is conducted above the lower phase transition temperature of the macromonomer, i.e., in the phase-separated regime, which provides a sufficiently concentrated macromonomer phase mandatory to obtain high-molar-mass cylindrical brushes. Upon heating to the phase transition temperature, the hydrodynamic radius is observed to shrink from 34 to 27 nm. Further increase in temperature resulted in aggregated chains which were observed to coexist with single chains until eventually only aggregates of μm size were detectable.

achaete-scute complex (ASC) genes, which encode basic helix-loop-helix transcription factors, regulate embryonic and adult neurogenesis in many animals. In adult arthropods, including crustaceans, ASC homologs have been identified but rarely functionally characterized. We took advantage of the recently identified crustacean homolog, splash (spiny lobster achaete scute homolog), in the olfactory organ of the Caribbean spiny lobster Panulirus argus to examine its role in adult neurogenesis. We tested the hypothesis that splash is associated with but not restricted to sensory neuron formation in the olfactory organ, the antennular lateral flagellum (LF), of adult spiny lobsters. We demonstrated splash labeling in epithelial cells across LF developmental zones (i.e., proliferation and mature zones), in auxiliary cells surrounding dendrites of olfactory receptor neurons (ORNs), and in immature and mature ORNs, but not in granulocytes or chromatophores. Since ORN proliferation varies with molt stage, we examined splash expression across molt stages and found that molt stage affected splash expression in the ORN mature zone but not in the proliferation zone. In vivo incorporation of bromodeoxyuridine (BrdU) showed no correlation in the cellular pattern of splash expression and BrdU labeling. The intensity of splash labeling was dramatically enhanced in the proliferation zones following LF damage, suggesting enhanced splash expression during repair and/or regeneration. We conclude that splash is not closely associated with the formation of sensory neurons under normal physiological conditions, and we propose that splash is involved in repair and regeneration. We also propose that splash has additional roles other than neurogenesis in adult crustaceans. © Wiley Periodicals, Inc. Develop Neurobiol 71: 316–335, 2011

Pushing the limits: A 200A - 10 Da structurally defined, linear macromolecule (PG5) has a molar mass, cross-section dimension, and cylindrical shape that are comparable to some naturally occurring objects, such as amyloid fibrils or certain plant viruses. The macromolecule is resistant against flattening out on a surface; the picture shows PG5 embracing the tobacco mosaic virus (TMV).

Surface charge, surface state density and interface recombination behavior on polished float zone (FZ) solar cell substrates were investigated after various wet-chemical pre-cleaning procedures and deposition of amorphous silicon (a-Si:H) or silicon nitride (a-SiNx:H). Applying surface photo voltage (SPV), microwave detected photo conductance decay (µW-PCD) and transient microwave conduction (TRMC) measurements, electronic interface properties were monitored repeatedly during the preparation processes. As shown for an inverted a-Si:H/c-Si hetero-junction structure, with front side passivation by a-SiNx:H and a p-type a-Si:H emitter on the rear side, the effect of optimised wet-chemical pre-treatment can be preserved during the subsequent soft plasma enhanced chemical vapour deposition of a-Si:H or a-SiNx:H. This leads to hetero-interfaces with low interface recombination velocities. These results were compared to previously reported findings, obtained on textured Czochralski (CZ) single crystalline substrates. a-SiNx:H is known to result in a field effect passivation. Nevertheless a strong influence of wet-chemical treatments on surface charge and recombination losses was observed on both flat and textured a-SiNx:H/c-Si interfaces. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The synthesis of Si/SiO 2 nanostructures for the application as hetero-emitter and passivation layer in high-efficiency solar cells is explored with the long-term perspective of exploiting quantum size effects for next-generation photovoltaics. Ultrathin oxides are developed by means of oxidizing crystalline silicon using neutral oxygen atoms supplied by a RF plasma source. These oxides are characterized by an abrupt Si/SiO 2 junction and good passivation of Si dangling bonds at the interface, a precondition for the implementation of Si/SiO 2 nanostructures in photovoltaic devices. Another decisive issue is carrier transport across the SiO 2 barrier which is demonstrated in form of a tunneling current in I―V measurements. Such tunneling oxides on Si(111) wafers are used as substrates for the subsequent deposition of Si nanodots. Nanodot synthesis is accomplished by first depositing a few nanometer thick layer of amorphous Si. During a subsequent recrystallization step at T > 600 °C, the surface tension between c-Si and SiO 2 causes a dewetting and, thus, the formation of crystalline Si nanodots, the size of which can be controlled by the thickness of the initial amorphous Si layer. Finally the dots are cladded with a shell of tunneling oxide. A close-packing of spheres with dots stacked on top of each other is approximated by a repetition of this process.

The promotion effect of a variety of inorganic oxides on the catalytic epoxidation of 1-octene with hydrogen peroxide catalyzed by (cis-Ph2PCH = CHPPh2)Pt(CF3)X (X = CH2Cl2, ·OH) in the liquid phase is reported. Catalysts were prepared either by mixing the oxides directly in the reaction medium or by impregnation of the oxides with the complexes prior to catalysis. A significant increase in the catalytic activity is obtained under certain experimental conditions and this is interpreted as a cooperation effect taking place at the interface between solid support and solution.

A semi-analytical model to describe the excess carrier concentration-dependent recombination processes and the charge carrier lifetime in a-Si:H/c-Si heterostructures has been developed. In contrast to previously proposed models it accounts for most relevant physical processes: In addition to bulk recombination processes the recombination via distributed dangling bond defects at the interface is integrated. Furthermore interface band bending depending on the a-Si:H doping and the Fermi-level dependent defect charge is taken into consideration as well as charge carrier diffusion to the interface. Despite its complexity the model allows for rapid computation and is thus well suited for fitting lifetime measurements in order to extract interface parameters. The model is crosschecked for various experimentally relevant situations against the numerical simulation tool AFORS-HET (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The complex formation of pUC19 DNA and a cylindrical brush polymer with quaternized poly(vinyl pyridinium) side chains is investigated by stopped flow light scattering (LS). In highly dilute solutions up to two kinetic processes are observable, depending on the mole fraction of anionic charges, x(anion) . For x(anion) 0.4-0.5 only one kinetic process was identified leading to the largest complexes at x(anion) = 0.4 well below charge stoichiometry. For 0.2

The complex formation of oppositely charged surfactants with some polypeptides is known to induce β-sheet or helix formation. Here, we report on the complex formation of cylindrical brush polymers with poly(L-lysine) side chains and sodium dodecylsulfate (SDS). With increasing amount of added surfactant the cylindrical polymers first adopt a helical conformation with a pitch of approximately 14-24 nm followed by a spherically collapsed structure before eventually precipitation occurs. CD measurements suggest that the helix formation of the cylindrical brush polymers is driven by the hydrophobicity of the ,8-sheets formed by the PLL side chain-SDS complexes.

Continuous neurogenesis persists during adulthood in the olfactory midbrain of decapod crustaceans, including spiny lobsters, Panulirus argus. This encompasses generation of projection and local interneurons, whose somata are in the lateral soma cluster (LC) and medial soma cluster (MC), respectively. Both neuronal types originate from immediate precursors labeled by a single injection of BrdU and located in a small proliferation zone within each cluster. The aim of this study was to identify neuroblasts as a source of the dividing cells by multiple injections of BrdU over 2 days. All animals receiving multiple injections had one or a few ‘extra’ BrdU-positive nuclei near the proliferation zones, and these nuclei were significantly larger than nuclei of neurons or BrdU-positive cells in the proliferation zones. Since the defining morphological feature of neuroblasts in preadult neurogenesis in arthropods is being larger than their progeny, these large extra BrdU-positive nuclei represent “putative adult neuroblasts.” Multiple BrdU-injections revealed a clump of small cells enclosing the putative adult neuroblasts in LC and MC, and these cells shared morphological characteristics with newly identified putative glial cells in the soma clusters and perivascular cells in the walls of arterioles. These results on P. argus suggest that adult neurogenesis is based on one adult neuroblast per soma cluster, adult neurogenesis appears to be a continuation of embryonic and larval neurogenesis, and the newly identified clumps of cells surrounding the putative adult neuroblasts might provide them with specific microenvironments necessary for their unusual lifelong proliferative and self-renewal capacity. J. Comp. Neurol. 503:64–84, 2007. © 2007 Wiley-Liss, Inc.

This study introduces the peroneus brevis muscle of the NZW-rabbit as a new model for free functional muscle transplantation. The muscle originates from the lateral aspect of the knee joint and inserts on the 5th metatarsal with a circumscript tendon. It can be harvested with a 7 cm long motor nerve branch. In a series of 22 animals divided in two groups with a body weight of 3.19 ± 0.30 kg and 4.81 ± 0.38 kg respectively, vessel diameter of the supplying artery was found to be 0.3–0.35 mm in group one and 0.40–0.45 mm in group two, the two concomitant veins were 1.1–1.4 mm in diameter in the first group and 1.2–1.6 mm in the second group. Histomorphometric analysis stained with NADH showed 3.67 ± 3.21% type I fibers, 25.41 ± 7.87% type IIa fibers, and 70.93 ± 9.12% type IIb/d fibers. © 2006 Wiley-Liss, Inc. Microsurgery, 2006.

We present the optimization and characterization of heterojunction solar cells consisting of an amorphous silicon emitter, a single crystalline absorber and an amorphous silicon rear side which causes the formation of a back surface field (a-Si:H/c-Si/a-Si:H). The solar cells were processed at temperatures 17% on p-type c-Si absorbers and >17·5% on n-type absorbers. In contrast to the approach of Sanyo, no additional intrinsic a-Si:H layers between the substrate and the doped a-Si:H layers were inserted. Copyright © 2006 John Wiley & Sons, Ltd.

Amphiphilic cylindrical brush-coil block copolymers consisting of a polystyrene coil and a cylindrical brush block with poly(acrylic acid) side chains are prepared by ATRP of t-butylacrylate from a block comacroinitiator. Upon acidolysis of the poly(t-butylacrylate), water-soluble polymers were obtained that were observed to form micelles consisting of 4-5 block copolymers on average in aqueous solution. The star-like nature of such micelles was clearly visualized by scanning force microscopy.

Cylindrical brushes with poly(L-lysine) and poly(L-glutamate) side chains were prepared by grafting through and grafting from techniques. Grafting from is shown to be more successful for the synthesis of cylindrical brushes with high molar mass main and side chains.

A homologous series of first- to fourth-generation (G1±G4) dendronized macromonomers, 5, 7, 10, and 12, was synthesized, and their poly- merization behavior under radical con- ditions investigated. These conditions were thermally induced radical poly- merization (TRP) and atom-transfer radical poymerization (ATRP). TRP was applied to all monomers and gave polymers PG1±PG4, whose molar masses range from several millions for PG1 to estimated several hundreds of thousands for PG2 and PG3, and to the oligomeric regime for PG4. ATRP was applied only to the G1 and G2 monomers 5 and 7. Kinetic studies on monomer 5 provide evidence that its polymerization proceeds in a control- led fashion. The highest monomer-to- initiator ratios which still gave mono- modal molar mass distributions were 300:1 (for 5) and 100:1 (for 7), which correspond to achievable molar mass regime for PG1 and PG2 of approxi- mately Mn = 100 000 (DPcalcd(PG1) = 200, DPcalcd(PG2) = 90). The polydis- persities lie in the usual range (PDI = 1.1±1.2). The molar masses were deter- mined by GPC in DMF with calibra- tion against absolute molar masses of PG1 determined by light scattering.

The fate of continuously generated cells in the soma clusters of the olfactory midbrain of adult spiny lobsters, Panulirus argus, was investigated by in vivo pulse-chase experiments with the proliferation marker 5-bromo-2*-deoxyuridine (BrdU) combined with immunostainings for neuropeptides of mature neurons. A BrdU injection after a survival time (ST) of 14 h labeled about 100 nuclei in the lateral soma clusters (LC), comprised of projection neurons, and about 30 nuclei in the medial soma clusters (MC), comprised of local interneurons. The BrdU-positive nuclei were con- fined to small regions at the inside of these clusters, which also contain nuclei in different phases of mitosis and thus represent proliferative zones. After STs of 2 weeks or 3 months, the number of BrdU-positive nuclei was doubled, indicating a mitosis of all originally labeled cells. Dependent on ST, the BrdU-positive nuclei were translocated from the proliferative zones towards the outside of the clusters, where somata of mature neurons reside. Immunostainings with antibodies to the neu- ropeptides FMRFamide and substance P, both of which label a large portion of somata in the MC and a pair of giant neurons projecting into the LC, revealed that in both clusters the proliferative zones are surrounded by, but are themselves devoid of, labeling. In the MC, some BrdU-positive somata were double-labeled by the FMRFamide antibody after an ST of 3 months, and by the substance P antibody after STs of 6 and 11/14 months, but not after 3 months. In the LC, BrdU-posi- tive somata after an ST of 3 months partially and after 6 and 11/14 months widely overlapped with the ar- borizations of the giant neurons, indicating the estab- lishment of synaptic input. The experiments show that cells generated in proliferative zones in the LC and MC of adult spiny lobsters after a final mitosis differentiate into neurons within months, survive for at least 1 year, and are integrated into the circuitry of the olfactory midbrain. A new hypothesis about the mechanism of adult neurogenesis in the central olfactory pathway of decapod crustaceans is developed, linking it to neuro- genesis during embryonic and larval develop

The number of olfactory projection neurons (OPNs) in the brain of the juvenile and adult shore crab Carcinus maenas continues to increase during the life of the animal. In vivo labeling of adult crabs with the proliferation marker bromodeoxyuridine (BrdU) revealed a group of proliferating neuronal precursor cells in the lateral soma clusters (LCs) and in the soma clusters of the hemiellipsoid bodies (HBCs). The LCs contain the cell bodies of the olfactory projection neurons and the HBCs house the cell bodies to which the OPNs project. The aim of the present study was to examine whether the input from primary olfactory afferents has any influence on the rate of proliferation and survival of the neuronal precursors in the central olfactory pathways of C. maenas. Different sets of experiments involving BrdU injection and its immunocytochemical detection combined with unilateral amputation of the antennule that houses the olfactory organ were carried out. Our results show that the missing olfactory sensory input affects the rate of proliferation and the survival of postmitotic cells in the LC and in the HBC compared with control animals. The effect on the survival of postmitotic cells tested by BrdU injection followed by unilateral ablation is lateralized. Proliferation of neuronal precursor cells tested by the reversed experimental order was drastically impaired bilaterally. We conclude that the olfactory sensory input is necessary for a normal rate of proliferation of neuronal precursors and the survival of their progeny in the LC and in the HBC of C. maenas. J. Comp. Neurol. 441:223–233, 2001. © 2001 Wiley-Liss, Inc.

To compare the stomatogastric nervous system of the crayfish Cherax destructor with those of other decapod species, the distribution of FLRF (Phe-Leu-Arg-Phe) amide-, proctolin- and crustacean cardioactive peptide (CCAP)-like immunoreactivities was studied in the stomatogastric nervous system and in neurosecretory structures by using wholemount immunocytochemical techniques and confocal microscopy. In addition, the number of cells in the stomatogastric ganglion (19–24) and axon profiles in the stomatogastric nerve (157–165) were counted. FLRFamide-like immunoreactivity was present within numerous cell bodies and neuropil of the commissural ganglia, in the neuropil of the stomatogastric ganglion, and in one cell body of the esophageal ganglion. FLRFamide-like immunoreactivity was also found in two cell bodies at the junction of the stomatogastric nerve with the superior esophageal nerve and in two cell bodies in the inferior ventricular nerve. Proctolin-like immunoreactivity was present in numerous cell bodies and neuropil of the paired commissural ganglia and in the neuropil of the stomatogastric ganglion. CCAP-like immunoreactivity was found in the neuropil and in one to four cell bodies in the commissural ganglia. Both proctolin- and CCAP-immunoreactive varicosities occurred on the surface of the circumesophageal connectives and on the postesophageal commissure, indicating a neurohemal source within the stomatogastric nervous system, which was verified by electron microscopy. The pericardial organs showed FLRFamide-, proctolin-, and CCAP-like immunoreactivity. This staining pattern suggests that FLRFamide-like and proctolin-like peptides are used as neurohormones and as neuromodulators in the stomatogastric nervous system of the crayfish C. destructor, whereas CCAP-like peptides may only affect the stomatogastric ganglion as a neurohormone. J. Comp. Neurol. 414:511–532, 1999. © 1999 Wiley-Liss, Inc.

Methacryloyl-endfunctionalized block copolymers consisting of styrene and 2-vinylpyridine were polymerized to polyblockcomacromonomers with a much higher main chain than side chain degree of polymerization. Like homopolymacromonomers these molecules exhibit the structure of cylindrical brushes. Since the vinylpyridine block is coupled to the polymerizable group, the resulting cylindrical macromolecules exhibit a core of vinylpyridine and a shell of polystyrene, thus resembling an amphipolar unimolecular micelle of cylindrical shape. The micellar character of the structure is demonstrated by loading the cylindrical brushes with tetrachloroauric acid in toluene. Subsequent reduction leads to the formation of colloidal gold, most probably within the brush in analogy to similar work on block copolymer micelles.

Based on the previous findings that the number of olfactory projection neurons increases continuously in adult shore crabs, Carcinus maenas, and that this increase is associated with the presence of 5-bromo-2′-deoxyuridine (BrdU)-positive, proliferating cells in the appropriate soma clusters (lateral soma clusters),1 we studied the further fate of these proliferating cells and the presence of apparent adult neurogenesis throughout the central olfactory pathway of diverse species of decapod crustaceans. Double labeling experiments combining biocytin-backfills and in vivo BrdU labeling as well as BrdU labelings with extended survival times (1 month) indicate that the cells proliferating in the lateral soma clusters of adult Carcinus undergo neuronal differentiation in about 3-4 weeks. In vivo BrdU labeling of different species representing important taxa of decapod crustaceans (shrimps, spiny lobsters, clawed lobsters, crayfish) revealed that neurogenesis among olfactory projection neurons is a constitutive feature of the adult decapod brain. In contrast, adult neurogenesis of the other neuron types present in the central olfactory pathway occurs in a taxon-specific manner and appears to be related to the development and reduction of accessory lobes throughout decapod phylogeny.

A self-consistent field (SCF) theory for the adsorption of polyelectrolyte chains onto oppositely charged spheres is considered. It is demonstrated that the criterion for critical adsorption shows a different behavior for small and large curvature of the surface. Experiments give indeed evidence for the power-law behavior as theoretically predicted for large curvature.

The polymerization of macromonomers provides polymers of extremely high branching density with regular branch length, branching number and branching interval. The intrinsic shape and size of these polymacromonomers were evaluated by small-angle X-ray scattering. The conformation of the backbone and side-chains was discussed. An oblate ellipsoid of revolution was proposed as an approximate shape of the polymacromonomers at a low degree of polymerization by scattering profile fitting. An elliptical cylinder was found to outline the polymacromonomer in solution at larger degrees of polymerization. The 3D molecular model of a polymacromonomer with a low degree of polymerization (DPM=7) suggested a random coil conformation for the backbone and side-chains. The conformational change of the backbone chain is speculated to take place when the total degree of polymerization exceeds a certain limiting value, where the polymacromonomer is represented by a molecular bottle brush as seen by light-scattering measurements. ©1997 SCI

Der Schwerpunkt der Synthese hat sich von neuen Polyreaktionen auf die gezielte Darstellung von Makromolekulsystemen mit spezieller molekularer Geometrie sowie geordneten Strukturen in kondensierter Phase verlagert. Bei Polymeren mit Funktionseigenschaften werden uber zielgerichtete Polymersynthesen vielfaltige Morphologien angestrebt. In den so erzeugten Mikrophasen konnen dann ionische, photonische oder elektronische Vorgange realisiert werden. Wirtschaftliche Aspekte beschliesen diesen Trendbericht.

Differently structured LPCVD-Si films are characterized by SEM, SIMS, optical transmission and reflection measurements, and photoconductivity yield measurements. In comparison to crystalline Si the optical absorption is high but the photoconductivity is poor. It is tried to improve the photoconductivity by post-annealing hydrogenation. The treatment with molecular hydrogen has only a small influence on the film properties.