Olfactory discrimination and memory deficits in the Flinders Sensitive Line rodent model of depression

Major Depressive Disorder (MDD) is a heterogeneous psychiatric disorder with broad symptomatic manifestations. The current study examined, for the first time, olfactory memory and discrimination in the Flinders Sensitive Line (FSL) rodent model of depression. Male FSL rats and controls were trained on an Olfactory Discrimination (OD) and a Social Interaction (SI) test. On the OD test, the FSL and controls performed similarly at the shortest inter-trial interval (5min), however, with extended delay of 30min, the FSLs had a recall and odour discrimination deficit. At the longest delay (60min) both groups performed poorly. The FSL rats i.) had a deficit in olfactory discrimination suggesting impairment in olfactory memory and recall; ii.) were less likely to socialize with unfamiliar rats. The data suggests that FSL animals have an impaired olfactory information processing capacity.

Single mode fiber based delivery of OAM light by 3D direct laser writing

We demonstrate orbital-angular momentum (OAM) light up to a topological charge of l=3 behind a single mode fiber. Femtosecond 3D direct laser writing is used to fabricate spiral phase plates of l=1,2 and 3, composed of 10 discrete steps, on the tip of single mode optical fibers. These structures efficiently convert out-coupled light from the fiber at 785 nm wavelength into optical vortex beams carrying an orbital-angular momentum of lℏper photon. Far field intensity patterns and interferograms of the OAM beams are recorded using a CCD camera. The results are in excellent agreement with numerical simulations obtained from the wave propagation method.

Landau-Zener Transition in a Continuously Measured Single-Molecule Spin Transistor

We monitor the Landau-Zener dynamics of a single-ion magnet inserted into a spin-transistor geometry. For increasing field-sweep rates, the spin reversal probability shows increasing deviations from that of a closed system. In the low-conductance limit, such deviations are shown to result from a dephasing process. In particular, the observed behaviors are successfully simulated by means of an adiabatic master equation, with time averaged dephasing (Lindblad) operators. The time average is tentatively interpreted in terms of the finite time resolution of the continuous measurement.

Single Quantum Dot with Microlens and 3D-Printed Micro-objective as Integrated Bright Single-Photon Source

Integrated single-photon sources with high photon-extraction efficiency are key building blocks for applications in the field of quantum communications. We report on a bright single-photon source realized by on-chip integration of a deterministic quantum dot microlens with a 3D-printed multilens micro-objective. The device concept benefits from a sophisticated combination of in situ 3D electron-beam lithography to realize the quantum dot microlens and 3D femtosecond direct laser writing for creation of the micro-objective. In this way, we obtain a high-quality quantum device with broadband photon-extraction efficiency of (40 ± 4)% and high suppression of multiphoton emission events with g⁽²⁾(τ = 0) < 0.02. Our results highlight the opportunities that arise from tailoring the optical properties of quantum emitters using integrated optics with high potential for the further development of plug-and-play fiber-coupled single-photon sources.

Rotationally symmetric formulation of the wave propagation method-application to the straylight analysis of diffractive lenses

We introduce a modified formulation of the wave propagation method for the efficient simulation of rotationally symmetric micro-optical components. The reformulated algorithm provides an increased computational performance of approximately two orders of magnitude and strongly reduced memory requirements, in comparison to the original formulation. This enables the efficient wave optical simulation of extended micro-optical structures beyond the common thin-element approximation. As a prototypical example, we assess the modified algorithm for the evaluation of straylight induced by diffractive lenses. We find an excellent accuracy, while comparing to rigorous simulations, which justifies the ability to overcome the limitations of the thin-element approximation.

3D-printed eagle eye: Compound microlens system for foveated imaging

We present a highly miniaturized camera, mimicking the natural vision of predators, by 3D-printing different multilens objectives directly onto a complementary metal-oxide semiconductor (CMOS) image sensor. Our system combines four printed doublet lenses with different focal lengths (equivalent to f = 31 to 123 mm for a 35-mm film) in a 2 × 2 arrangement to achieve a full field of view of 70° with an increasing angular resolution of up to 2 cycles/deg field of view in the center of the image. The footprint of the optics on the chip is below 300 μm × 300 μm, whereas their height is <200 μm. Because the four lenses are printed in one single step without the necessity for any further assembling or alignment, this approach allows for fast design iterations and can lead to a plethora of different miniaturized multiaperture imaging systems with applications in fields such as endoscopy, optical metrology, optical sensing, surveillance drones, or security.

Morphological Evolution of Electrochemically Plated/Stripped Lithium Microstructures Investigated by Synchrotron X-ray Phase Contrast Tomography

Due to its low redox potential and high theoretical specific capacity, Li metal has drawn worldwide research attention because of its potential use in next-generation battery technologies such as Li-S and Li-O2. Unfortunately, uncontrollable growth of Li microstructures (LmSs, e.g., dendrites, fibers) during electrochemical Li stripping/plating has prevented their practical commercialization. Despite various strategies proposed to mitigate LmS nucleation and/or block its growth, a fundamental understanding of the underlying evolution mechanisms remains elusive. Herein, synchrotron in-line phase contrast X-ray tomography was employed to investigate the morphological evolution of electrochemically deposited/dissolved LmSs nondestructively. We present a 3D characterization of electrochemically stripped Li electrodes with regard to electrochemically plated LmSs. We clarify fundamentally the origin of the porous lithium interface growing into Li electrodes. Moreover, cleavage of the separator caused by growing LmS was experimentally observed and visualized in 3D. Our systematic investigation provides fundamental insights into LmS evolution and enables us to understand the evolution mechanisms in Li electrodes more profoundly.

Multi-Scale Correlative Tomography of a Li-Ion Battery Composite Cathode

Focused ion beam/scanning electron microscopy tomography (FIB/SEMt) and synchrotron X-ray tomography (Xt) are used to investigate the same lithium manganese oxide composite cathode at the same specific spot. This correlative approach allows the investigation of three central issues in the tomographic analysis of composite battery electrodes: (i) Validation of state-of-the-art binary active material (AM) segmentation: Although threshold segmentation by standard algorithms leads to very good segmentation results, limited Xt resolution results in an AM underestimation of 6 vol% and severe overestimation of AM connectivity. (ii) Carbon binder domain (CBD) segmentation in Xt data: While threshold segmentation cannot be applied for this purpose, a suitable classification method is introduced. Based on correlative tomography, it allows for reliable ternary segmentation of Xt data into the pore space, CBD, and AM. (iii) Pore space analysis in the micrometer regime: This segmentation technique is applied to an Xt reconstruction with several hundred microns edge length, thus validating the segmentation of pores within the micrometer regime for the first time. The analyzed cathode volume exhibits a bimodal pore size distribution in the ranges between 0-1 μm and 1-12 μm. These ranges can be attributed to different pore formation mechanisms.

Ultra-compact on-chip LED collimation optics by 3D femtosecond direct laser writing

By using two-photon lithographic 3D printing, we demonstrate additive manufacturing of a dielectric concentrator directly on a LED chip. With a size of below 200 μm in diameter and length, light output is increased by a factor of 6.2 in collimation direction, while the emission half-angle is reduced by 50%. We measure excellent form fidelity and irradiance patterns close to simulation. Additionally, a more complex shape design is presented, which exhibits a nonconventional triangular illumination pattern. The introduced method features exceptional design freedoms which can be used to tailor high-quality miniature illumination optics for specific lighting tasks, for example, endoscopy.

Sub-micrometre accurate free-form optics by three-dimensional printing on single-mode fibres

Micro-optics are widely used in numerous applications, such as beam shaping, collimation, focusing and imaging. We use femtosecond 3D printing to manufacture free-form micro-optical elements. Our method gives sub-micrometre accuracy so that direct manufacturing even on single-mode fibres is possible. We demonstrate the potential of our method by writing different collimation optics, toric lenses, free-form surfaces with polynomials of up to 10th order for intensity beam shaping, as well as chiral photonic crystals for circular polarization filtering, all aligned onto the core of the single-mode fibres. We determine the accuracy of our optics by analysing the output patterns as well as interferometrically characterizing the surfaces. We find excellent agreement with numerical calculations. 3D printing of microoptics can achieve sufficient performance that will allow for rapid prototyping and production of beam-shaping and imaging devices.

Combining freeform optics with micro- and nano-optics can permit wavefront shaping, phase engineering, k-space and polarization control. Here, Gissibl et al. use femtosecond 3D printing to manufacture free-form optical elements, giving sub-micrometre accuracy so that direct manufacturing on single-mode fibres is possible.

Bimodal endoscopic probe combining white-light microscopy and optical coherence tomography

We present a novel bimodal endoscopic imaging probe that can simultaneously provide full-field white-light video microscopy and confocal optical coherence tomography (OCT) depth scans. The two modalities rely on spectrally separated optical paths that run partially in parallel through a micro-optical bench system, which has a cross-section of only 2  mm×2.76  mm and is realized via standard silicon micromachining techniques. With a numerical aperture of 0.061, the video modality has a resolution and field of view of 9.3 and 1240  μm×1080  μm, respectively. The resolution is limited by the pixel spacing of the coherent fiber bundle, which relays the acquired image from the distal to the proximal end. A custom-designed diffractive optical element placed within the video imaging path significantly improves the image contrast by up to 45% in the medium frequency range. The OCT modality is optimized for 830 nm center wavelength, and works in a confocal arrangement with an NA of 0.018. It provides single-point depth probing at the center of the video image with a lateral resolution of 20 μm. Through its compact footprint and enhanced functionality, the probe can provide depth-resolved guiding capability for existing laparoscopes and represents a major step toward a new class of multimodal endoscopic imaging probes.

p38 MAPK regulates the Wnt inhibitor Dickkopf-1 in osteotropic prostate cancer cells

The Wnt inhibitor Dickkopf-1 (DKK-1) has been associated with the occurrence of bone metastases in osteotropic prostate cancer by inhibiting osteoblastogenesis. P38 mitogen-activated protein kinase (MAPK) activity is also dysregulated in advanced prostate cancer. However, the impact of p38 MAPK signaling on DKK-1 remains unknown. Inhibition of p38 MAPK signaling in osteolytic PC3 cells by small molecule inhibitors (doramapimod, LY2228820 and SB202190) suppressed DKK-1 expression, whereas activation of p38 MAPK by anisomycin increased DKK-1. Further dissection by targeting individual p38 MAPK isoforms with siRNA revealed a stronger role for MAPK11 than MAPK14 and MAPK12 in the regulation of DKK-1. Moreover, prostate cancer cells with a predominantly osteolytic phenotype produced sufficient amounts of DKK-1 to inhibit Wnt3a-induced osteoblastic differentiation in C2C12 cells. This inhibition was blocked directly by neutralizing DKK-1 using a specific antibody and also indirectly by blocking p38 MAPK. Furthermore, tissue expression in human prostate cancer revealed a correlation between p38 MAPK and DKK-1 expression with higher expression in tumor compared with normal tissues. These results reveal that p38 MAPK regulates DKK-1 in prostate cancer and may present a potential target in osteolytic prostate cancers.

Influence of carbon substrate on the electrochemical performance of carbon/manganese oxide hybrids in aqueous and organic electrolytes

The carbon substrate has an important influence on the electrochemical performance of manganese oxide/carbon supercapacitors. Stable performance further requires asymmetric cell design in organic and aqueous electrolytes.

Three-dimensional morphology of the interface between micro porous layer and catalyst layer in a polymer electrolyte membrane fuel cell

FIB/SEM tomography and ALD infiltration are combined to analyse the interface between MPL and CL in a PEM fuel cell.

Directly deposited Nafion/TiO2 composite membranes for high power medium temperature fuel cells

This work presents a simple production method for TiO₂ reinforced Nafion® membranes which are stable up to a 120 °C operation temperature and achieve record breaking fuel cell efficiencies.

Adult osteochondritis dissecans and focussed ESWT: A successful treatment option

Extracorporeal shockwave therapy (ESWT) has gained acceptance in the medical field and in the treatment of non-unions and delayed bone healing. ESWT has been used effectively for many years as a noninvasive surgical procedure. The idea of treating Osteochondritis dissecans of knee and talus arose in the middle of the 1990's. OCD is known as a pre-arthritic factor in the long-term and still there is no consistent treatment. In the literature there is still only a small number of publications but international societies for shockwave treatment are convinced that ESWT on OCD shows to be an effective and safe method in the treatment of OCD in the early stages. We want to summarize the actual data on the treatment of OCD by ESWT.

Lateral epicondylitis: This is still a main indication for extracorporeal shockwave therapy

Extracorporeal shockwave therapy (ESWT) is used in a number of indications in the medical field. A number of tendinopathies show good and excellent results due to evidence based medicine. The treatment of lateral epicondylitis is known to show conflicting results. This overview of the published RCT's on ESWT for lateral epicondylitis tries to show the reasons for this conflicting data-base and point out, why we think that this is still a main indication for extracorporeal shockwave therapy.