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Reduced Etch Lag and High Aspect Ratios by Deep Reactive Ion Etching (DRIE)

Deep reactive ion etching (DRIE) with the Bosch process is one of the key procedures used to manufacture micron-sized structures for MEMS and microfluidic applications in silicon and, hence, of increasing importance for miniaturisation in biomedical research. While guaranteeing high aspect ratio structures and providing high design flexibility, the etching procedure suffers from reactive ion etchi

Optical feedback control loop for the precise and robust acoustic focusing of cells, micro- and nanoparticles

Despite a long history and the vast number of applications demonstrated, very few market products incorporate acoustophoresis. Because a human operator must run and control a device during an experiment, most devices are limited to proof of concepts. On top of a possible detuning due to temperature changes, the human operator introduces a bias which reduces the reproducibility, performance and rel

Acoustofluidic medium exchange for preparation of electrocompetent bacteria using channel wall trapping

Comprehensive integration of process steps into a miniaturised version of synthetic biology workflows remains a crucial task in automating the design of biosystems. However, each of these process steps has specific demands with respect to the environmental conditions, including in particular the composition of the surrounding fluid, which makes integration cumbersome. As a case in point, transform

Embedded Microbubbles for Acoustic Manipulation of Single Cells and Microfluidic Applications

Acoustically excited microstructures have demonstrated significant potential for small-scale biomedical applications by overcoming major microfluidic limitations. Recently, the application of oscillating microbubbles has demonstrated their superiority over acoustically excited solid structures due to their enhanced acoustic streaming at low input power. However, their limited temporal stability hi

Acoustic Radiation Forces Produced by Sharp-Edge Structures in Microfluidic Systems

We study sharp-edge structures that are used in microfluidic systems for particle and cell manipulation. Experiments show that oscillating sharp edges can attract or repel particles suspended in a microfluidic channel. This effect is caused by acoustic radiation forces induced by sharp edges. We propose an analytical theory that allows one to evaluate the acoustic radiation force produced by a sha

Manipulation of single cells inside nanoliter water droplets using acoustic forces

Droplet microfluidics enables high-throughput screening of single cells and is particularly valuable for applications, where the secreted compounds are analyzed. Typically, optical methods are employed for analysis, which are limited in their applicability as labeling protocols are required. Alternative label-free methods such as mass spectrometry would broaden the range of assays but are harmful

Acoustic streaming produced by sharp-edge structures in microfluidic devices

The effect of acoustic streaming produced by sharp-edge structures is used in a variety of microfluidic applications, such as fluid mixing, pumping and particle manipulation. Since most investigations into this effect are experimental, there is a necessity in theoretical studies that could provide a deeper insight into the mechanism of the acoustic streaming and point out ways for optimizing acous

Focusing of Micrometer-Sized Metal Particles Enabled by Reduced Acoustic Streaming via Acoustic Forces in a Round Glass Capillary

Two-dimensional (2D) metal-particle focusing is an essential task for various fabrication processes. While acoustofluidic devices can manipulate particles in two-dimensions, the production of these devices often demands a cleanroom environment. Therefore, acoustically excited glass capillaries present a cheap alternative to labor-intensive cleanroom production. Here, we present 2D metal microparti

Sex and gender differences in treatment intention, quality of life and performance status in the first 100 patients with periampullary cancer enrolled in the CHAMP study

BACKGROUND: Periampullary cancer is a term for cancers arising in or in close proximity to the pancreas. Pancreatic cancer is the 3rd leading cause of cancer death for both sexes and while surgery is the only option for cure, chemotherapy is given in both the adjuvant and palliative settings. The aim of this study was to investigate any sex and gender differences in patients with pancreatic and ot

The honest sound of physical effort

Acoustic correlates of physical effort are still poorly understood, even though effort is vocally communicated in a variety of contexts with crucial fitness consequences, including both confrontational and reproductive social interactions. In this study 33 lay participants spoke during a brief, but intense isometric hold (L-sit), first without any voice-related instructions, and then asked either

Virtual Workshop on Semantic mapping of archaeological excavation data

This report documents the presentations and discussions which took place on 15 June 2022 at the "Virtual Workshop on Semantic mapping of excavation data" on Zoom. The event was organised as an open forum to illustrate aspects of the work carried out by the Archaeological Excavation Modelling Working Group, a sub-group within WP 4.4.12. The presenters, both Partners and Associate Partners of the AR

Governing Black and White : A History of Governmentality in Denmark and the Danish West Indies, 1770-1900

This dissertation explores and compares the rationalities through which Danish state officials sought to govern the colonized Afro-Caribbean population in the colony of the Danish West Indies and the state’s Danish subjects living in the metropole of Denmark in the period 1770-1900. Theoretically, it relies upon Michel Foucault’s conception of ’governmentality’ and the way this approach to governi

Decryption Failure Attacks on Post-Quantum Cryptography

This dissertation discusses mainly new cryptanalytical results related to issues of securely implementing the next generation of asymmetric cryptography, or Public-Key Cryptography (PKC).PKC, as it has been deployed until today, depends heavily on the integer factorization and the discrete logarithm problems.Unfortunately, it has been well-known since the mid-90s, that these mathematical problems

Arbetslivsforskning vid Lunds universitet : En inventering av arbetslivsforskningens omfattning, hemvist och förutsättningar

Vi lever i en tid då arbetslivet – både i Sverige och globalt – genomgår storaförändringar och står inför stora utmaningar. Arbetslivsforskning har därför enstor samhällelig relevans. Men hur står det egentligen till med arbetslivsforskningen vid Lunds universitet? Hur många arbetslivsforskare finns det och var någonstans håller de hus? Och hur ser de på förutsättningarna för att bedriva arbetsliv

High resolution laboratory x-ray tomography for biomedical research : From design to application

Laboratory x-ray micro- and nano-tomography are emerging techniques in biomedical research. Through the use of phase-contrast, sufficient contrast can be achieved in soft tissue to support medical studies. With ongoing developments of x-ray sources and detectors, biomedical studies can increasingly be performed at the laboratory and do not necessary require synchrotron radiation. Particularly nano

AI-Prepared Autonomous Freshwater Monitoring and Sea Ground Detection by an Autonomous Surface Vehicle

Climate change poses special and new challenges to inland waters, requiring intensive monitoring. An application based on an autonomous operation swimming vehicle (ASV) is being developed that will provide simulations, spatially and depth-resolved water parameter monitoring, bathymetry detection, and respiration measurement. A clustered load system is integrated with a high-resolution sonar system

Pericytes in Hypoxia and Ischemic Stroke

Molecular oxygen is essential for most living species. Consequently, hypoxic or ischemic conditions are major cellular stressors and prominent pathological features in ischemic stroke. Stroke is a global health problem and remains the second leading cause of death or disability worldwide. Current management of the disease focuses on rapid reperfusion by thrombolysis or thrombectomy but these thera

Digitalizing Welfare: The role of encounters in supporting marginalised citizens’ access to rights in the Danish welfare state

Digitalisation of the public sector is advocated for as an efficient and responsive approach to the delivery of public services. In this article, we analyse the role of digitalisation from a bottom-up perspective as we zoom in on socially marginalised citizens’ access to welfare rights in the context of the digitalised Danish welfare state. In the Danish welfare state, the authority and responsibi