Modeling the partially detected backside reflectance of transparent substrates in reflectance microspectroscopy.

Thick transparent substrates are a key component for transmissive thin film optical filters and optoelectronics. In optical characterization of such substrates, light reflected from the backside - whether fully or partially detected - interferes with light directly reflected from the substrate's front side. Herein, we introduce a straightforward approach for microspectroscopic measurements, with lateral dimensions in the micrometer range, to reliably assess the amount of measured backside reflectance.

Apolipoprotein A1 (CSL112) Increases Lecithin-Cholesterol Acyltransferase Levels in HDL Particles and Promotes Reverse Cholesterol Transport.

Although high-density lipoprotein (HDL) cholesterol is inversely correlated with cardiovascular risk, an emerging paradigm is focused on increasing reverse cholesterol transport (RCT) and HDL function via apolipoprotein A1 (ApoA1). The objective of this study was to investigate the effect of ApoA1 (CSL112) infusion on HDL protein composition, cholesterol esterification rate (CER), and cholesterol efflux capacity (CEC) in patients treated after acute myocardial infarction. CSL112 reduced levels of apolipoproteins A2, B, C, and E and serum amyloids A1 and A4, whereas ApoA1, ApoM, and lecithin-cholesterol acyltransferase were significantly elevated.

Bacterial flagella hijack type IV pili proteins to control motility.

Bacterial flagella and type IV pili (TFP) are surface appendages that enable motility and mechanosensing through distinct mechanisms. These structures were previously thought to have no components in common. Here, we report that TFP and some flagella share proteins PilO, PilN, and PilM, which we identified as part of the flagellar motor.

A 4H-SiC CMOS Oscillator-Based Temperature Sensor Operating from 298 K up to 573 K.

In this paper, we propose a temperature sensor based on a 4H-SiC CMOS oscillator circuit and that is able to operate in the temperature range between 298 K and 573 K. The circuit is developed on Fraunhofer IISB's 2 μm 4H-SiC CMOS technology and is designed for a bias voltage of 20 V and an oscillation frequency of 90 kHz at room temperature. The possibility to relate the absolute temperature with the oscillation frequency is due to the temperature dependency of the threshold voltage and of the channel mobility of the transistors.

Correlating Optical Microspectroscopy with 4×4 Transfer Matrix Modeling for Characterizing Birefringent Van der Waals Materials.

Van der Waals materials exhibit intriguing properties for future electronic and optoelectronic devices. As those unique features strongly depend on the materials' thickness, it has to be accessed precisely for tailoring the performance of a specific device. In this study, a nondestructive and technologically easily implementable approach for accurate thickness determination of birefringent layered materials is introduced by combining optical reflectance measurements with a modular model comprising a 4×4 transfer matrix method and the optical components relevant to light microspectroscopy.

Suppression of MR1 by human cytomegalovirus inhibits MAIT cell activation.

Introduction: The antigen presentation molecule MHC class I related protein-1 (MR1) is best characterized by its ability to present bacterially derived metabolites of vitamin B2 biosynthesis to mucosal-associated invariant T-cells (MAIT cells).

Methods: Through in vitro human cytomegalovirus (HCMV) infection in the presence of MR1 ligand we investigate the modulation of MR1 expression. Using coimmunoprecipitation, mass spectrometry, expression by recombinant adenovirus and HCMV deletion mutants we investigate HCMV gpUS9 and its family members as potential regulators of MR1 expression.

The human cytomegalovirus decathlon: Ten critical replication events provide opportunities for restriction.

Human cytomegalovirus (HCMV) is a ubiquitous human pathogen that can cause severe disease in immunocompromised individuals, transplant recipients, and to the developing foetus during pregnancy. There is no protective vaccine currently available, and with only a limited number of antiviral drug options, resistant strains are constantly emerging. Successful completion of HCMV replication is an elegant feat from a molecular perspective, with both host and viral processes required at various stages.

UL49 is an essential subunit of the viral pre-initiation complex that regulates human cytomegalovirus gene transcription.

More than half the world's population is infected with human cytomegalovirus (HCMV), causing congenital birth defects and impacting the immuno-compromised. Many of the >170 HCMV genes remain uncharacterized, and this gap in knowledge limits the development of novel antivirals. In this study, we investigated the essential viral protein UL49 and found it displayed leaky late expression kinetics, and localized to nuclear replication compartments.

A Highly Specific Holin-Mediated Mechanism Facilitates the Secretion of Lethal Toxin TcsL in .

Protein secretion is generally mediated by a series of distinct pathways in bacteria. Recently, evidence of a novel bacterial secretion pathway involving a bacteriophage-related protein has emerged. TcdE, a holin-like protein encoded by toxigenic isolates of , mediates the release of the large clostridial glucosylating toxins (LCGTs), TcdA and TcdB, and TpeL from uses another holin-like protein, TpeE, for its secretion; however, it is not yet known if TcdE or TpeE secretion is specific to these proteins.

Mechanisms of Ohmic Contact Formation of Ti/Al-Based Metal Stacks on p-Doped 4H-SiC.

Ohmic contacts on p-doped 4H-SiC are essential for the fabrication of a wide range of power electron devices. Despite the fact that Ti/Al based ohmic contacts are routinely used for ohmic contacts on p-doped 4H-SiC, the underlying contact formation mechanisms are still not fully understood. TLM structures were fabricated, measured and analyzed to get a better understanding of the formation mechanism.

Advancing the sensitivity of integrated epoxy-based Bragg grating refractometry by high-index nanolayers.

In this Letter, we report on significantly improved surrounding RI sensitivity of epoxy polymer waveguide Bragg grating sensors. Uniform Bragg gratings were generated inside flat rectangular epoxy waveguides near the cutoff regime using standard phase mask excimer laser writing. Thickness controlled nanolayers of high-index titanium dioxide were deposited homogeneously on the waveguide sensor's surface area by repeated reactive sputter processing.

The host exosome pathway underpins biogenesis of the human cytomegalovirus virion.

Human Cytomegalovirus (HCMV) infects over half the world's population, is a leading cause of congenital birth defects, and poses serious risks for immuno-compromised individuals. To expand the molecular knowledge governing virion maturation, we analysed HCMV virions using proteomics, and identified a significant proportion of host exosome constituents. To validate this acquisition, we characterized exosomes released from uninfected cells, and demonstrated that over 99% of the protein cargo was subsequently incorporated into HCMV virions during infection.

Highly accurate determination of heterogeneously stacked Van-der-Waals materials by optical microspectroscopy.

The composition of Van-der-Waals heterostructures is conclusively determined using a hybrid evaluation scheme of data acquired by optical microspectroscopy. This scheme deploys a parameter set comprising both change in reflectance and wavelength shift of distinct extreme values in reflectance spectra. Furthermore, the method is supported by an accurate analytical model describing reflectance of multilayer systems acquired by optical microspectroscopy.

Laser Surface Microstructuring of a Bio-Resorbable Polymer to Anchor Stem Cells, Control Adipocyte Morphology, and Promote Osteogenesis.

New strategies in regenerative medicine include the implantation of stem cells cultured in bio-resorbable polymeric scaffolds to restore the tissue function and be absorbed by the body after wound healing. This requires the development of appropriate micro-technologies for manufacturing of functional scaffolds with controlled surface properties to induce a specific cell behavior. The present report focuses on the effect of substrate topography on the behavior of human mesenchymal stem cells (MSCs) before and after co-differentiation into adipocytes and osteoblasts.

Topic Review: Application of Raman Spectroscopy Characterization in Micro/Nano-Machining.

The defects and subsurface damages induced by crystal growth and micro/nano-machining have a significant impact on the functional performance of machined products. Raman spectroscopy is an efficient, powerful, and non-destructive testing method to characterize these defects and subsurface damages. This paper aims to review the fundamentals and applications of Raman spectroscopy on the characterization of defects and subsurface damages in micro/nano-machining.

Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters.

Polydimethylsiloxane (PDMS) is a promising biomaterial for generating artificial extracellular matrix (ECM) like patterned topographies, yet its hydrophobic nature limits its applicability to cell-based approaches. Although plasma treatment can enhance the wettability of PDMS, the surface is known to recover its hydrophobicity within a few hours after exposure to air. To investigate the capability of a novel PDMS-type (X-PDMS) for based assessment of physiological cell properties, we designed and fabricated plane as well as nano- and micrometer-scaled pillar-patterned growth substrates using the elastomer types S-, H- and X-PDMS, which were fabricated from commercially available components.

Waveguide Bragg Gratings in Ormocers for Temperature Sensing.

Embedded channel waveguide Bragg gratings are fabricated in the Ormocer hybrid polymers OrmoComp, OrmoCore, and OrmoClad by employing a single writing step technique based on phase mask technology and KrF excimer laser irradiation. All waveguide Bragg gratings exhibit well-defined reflection peaks within the telecom wavelengths range with peak heights of up to 35 dB and -3 dB-bandwidths of down to 95 pm. Furthermore, the dependency of the fabricated embedded channel waveguide Bragg gratings on changes of the temperature and relative humidity are investigated.

Herpesviruses hijack host exosomes for viral pathogenesis.

Herpesviruses are remarkable pathogens possessing elaborate mechanisms to seize various host cellular components for immune evasion, replication, and virion egress. As viruses are dependent upon their hosts, investigating this intricate interplay has revealed that the exosome pathway is utilised by alpha (Herpes Simplex Virus 1), beta (Human Cytomegalovirus, and Human Herpesvirus 6) and gamma (Epstein-Barr Virus, and Kaposi Sarcoma-associated Herpesvirus) herpesviruses. Virions and exosomes share similar properties and functions.

Extracellular vesicles: their role in cancer biology and epithelial-mesenchymal transition.

Cell-cell communication is critical across an assortment of physiological and pathological processes. Extracellular vesicles (EVs) represent an integral facet of intercellular communication largely through the transfer of functional cargo such as proteins, messenger RNAs (mRNAs), microRNA (miRNAs), DNAs and lipids. EVs, especially exosomes and shed microvesicles, represent an important delivery medium in the tumour micro-environment through the reciprocal dissemination of signals between cancer and resident stromal cells to facilitate tumorigenesis and metastasis.

A Portrait of the Human Organelle Proteome In Space and Time during Cytomegalovirus Infection.

The organelles within a eukaryotic host are manipulated by viruses to support successful virus replication and spread of infection, yet the global impact of viral infection on host organelles is poorly understood. Integrating microscopy, subcellular fractionation, mass spectrometry, and functional analyses, we conducted a cell-wide study of organelles in primary fibroblasts throughout the time course of human cytomegalovirus (HCMV) infection. We used label-free and isobaric-labeling proteomics to characterize nearly 4,000 host and 100 viral proteins, then classified their specific subcellular locations over time using machine learning.

Stimulatory effects of advanced glycation endproducts (AGEs) on fibronectin matrix assembly.

Advanced glycation endproducts (AGEs) are a heterogeneous group of compounds that form via non-enzymatic glycation of proteins throughout our lifespan and at a higher rate in certain chronic diseases such as diabetes. AGEs contribute to the progression of fibrosis, in part by stimulating cellular pathways that affect gene expression. Long-lived ECM proteins are targets for non-enzymatic glycation but the question of whether the AGE-modified ECM leads to excess ECM accumulation and fibrosis remains unanswered.

Waveguide Bragg gratings in Ormocer hybrid polymers.

We report on the fabrication of Bragg gratings within rib-type waveguides of previously UV-cured inorganic-organic Ormocer hybrid polymers by applying the interferometric phase mask technique in conjunction with deep-UV laser radiation. The fabrication process as well as the influence of the applied laser fluence and the length of the Bragg grating on the characteristics of the Bragg grating's transmission and reflection spectra are discussed and compared to numerical simulations and calculations. Depending on the applied laser fluence and the chosen grating length, waveguide Bragg gratings with strong reflectivities of up to 98 % and narrow bandwidths of down to 120 pm have been achieved.