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The interaction of atoms with intense laser radiation leads to the generation of high-order harmonics of the laser field. In the time domain, this corresponds to a train of pulses in the extreme ultraviolet range and with attosecond duration. This tutorial will introduce the physics of high-order harmonic generation and attosecond pulses.

Efficient, diode-pumped high energy femtosecond laser systems around 1 μm based on Yb-gain media are readily commercially available. However, owing to the gain bandwidth limitations, the pulses generated in such lasers are substantially longer than the ones generated in Ti:Sapphire systems. A simple, energy-scalable pulse self-compression scheme for the pulses around 1 μm thus would be of great in

Manipulation of electrons by light forms the basis for future optoelectronic devices targeting switching speeds close to optical frequencies. Specifically, nanolocalized optical and plasmonic fields play a key role as they reduce the interaction region down to few nanometers and thus the time electrons require to traverse the fields. In this context, the precise knowledge of the localized fields i

This work aims to investigate the breakup dynamics of the gas-liquid interface during bubble formation in a microchannel flow-focusing device. An interface tracking method is developed to capture the profiles of the gaseous thread evolution. The results show that the pinch-off period can be further divided into a liquid squeezing stage and a free pinch-off stage in both the radial and axial direct

This work aims to investigate the breakup dynamics of the low-density gas and liquid interface during bubble formation in a microchannel flow-focusing device. A high-contrast interface tracking method is developed. After the neck motion analysis in radial and axial directions, the time domain criterion between the liquid squeezing stage and the free pinch-off stage is proved to be two orders of ma

High-temperature PEM fuel cells (HT-PEMFCs) are of current interest due to their favorable characteristics in relation to PEM fuel cells operating at a low temperature (LT-PEMFCs). The benefits concern poisoning of the CO catalyst, water management, thermal management and humidity issues. The major challenge facing these fuel cells is to have the membrane performing well at high temperature. This

The flow and temperature fields in packed beds are rather complex but are of great importance since they will influence macroscopic parameters and the overall performance of the packed bed system. Regions with either too high or too low velocity are not preferred since they will decrease the heat and mass transfer characteristics of packed beds. The residence time distribution (RTD) is a way to as

This study numerically investigates film-cooling performance and particle trajectories in AGTB (two rows of cylindrical holes equipped on suction side (SS) and pressure side (PS) of the leading edge, respectively) turbine cascade. Particle deposition on a turbine blade is analyzed by calculations of capture efficiency and impact efficiency. The turbulent flow is modeled by the Realizable k-ε turbu

The field synergy principle has three criteria to qualitatively describe the essence of single-phase convective heat transfer enhancement. However, in practice these criteria are difficult to be applied to convective heat transfer analysis, because there are no corresponding indicators available to quantitatively describe them. Therefore, a unified formula for the field synergy principle was devel

Objective: Late age at first childbirth is a well-established risk factor for breast cancer. Previous studies have, however, shown conflicting results to whether late age at first childbirth also influences the prognosis of breast cancer survival. The aim of this study was to examine age at first birth in relation to survival after breast cancer diagnosis. Results: We used information from the Mal

BACKGROUND: Hospital performance, presented as the comparison of average measurements, dismisses that hospital outcomes may vary across types of patients. We aim at drawing out the relevance of accounting for patient heterogeneity when reporting on hospital performance.METHODS: An observational study on administrative data from virtually all 2009 hospital admissions for Acute Myocardial Infarction

Magnetic hysteresis is demonstrated for monolayers of the single-molecule magnet (SMM) Dy2ScN@C80 deposited on Au(111), Ag(100), and MgO|Ag(100) surfaces by vacuum sublimation. The topography and electronic structure of Dy2ScN@C80 adsorbed on Au(111) were studied by STM. X-ray magnetic CD studies show that the Dy2ScN@C80 monolayers exhibit similarly broad magnetic hysteresis independent on the sub

Background: Patients with inflammatory bowel disease (IBD) often develop alterations in body composition in terms of their proportions of lean mass and fat mass, as well as reduced bone mineral density (BMD). However, there are limited data on the skeletal muscle index (SMI) and percentage fat (fat %) for young adults with childhood-onset IBD. Our aim was to investigate the body compositions of th

The term “fracture cascade” refers to the sequence of fragility fractures resulting from the increased fracture risk that occurs with aging and following fractures. Here, we evaluate the sequence of previous fractures in women aged 55 to 90 years presenting with a fragility fracture and subsequent (12 to 24 months) fracture incidence. In this retrospective, observational study, women aged 55 to 90

This paper experimentally investigates heat dissipation of a heat pipe with phase change materials (PCMs) cooling in a multiple heat source system. Two heat sources are fixed at one end of the heat pipe. Considering that a heat sink cannot dissipate all the heat generated by two heat sources, various PCMs are used due to a large latent heat. Different materials in a container are wrapped outside o

Introduction: Oncoplastic breast surgery (OBS) has developed as an extension of breast-conserving surgery (BCS) in an effort to improve esthetic and functional outcome following surgery for breast cancer. The aim of the present study was to evaluate the possible benefits of OBS, as compared with BCS, with regard to health-related quality of life (HRQoL), using patient-reported outcome measures (PR

Impaired lung function is often caused by cigarette smoking, making it challenging to disentangle its role in lung cancer susceptibility. Investigation of the shared genetic basis of these phenotypes in the UK Biobank and International Lung Cancer Consortium (29,266 cases, 56,450 controls) shows that lung cancer is genetically correlated with reduced forced expiratory volume in one second (FEV1: r

This study presents a state-of-the-art overview on the application of ultrasound technology in the drying of food products, including the ultrasound pre-treatment and ultrasound assisted drying. The effect of main parameters and ultrasound technology on the drying kinetics and food quality were discussed. Inconsistencies were pointed out and analyzed in detail. Results showed that for ultrasound p

Augmentation of heat transfer must always be judged against an additional pressure loss. To this context, this paper explores slitted ribs on the turbulent flow and heat transfer characteristics in rectangular cooling channels with an aspect ratio of 4:1. A verified v2f turbulence model is applied in the present numerical simulations in the Reynolds number range from 20,000 to 80,000. The flow and

Introduction: Oral contraceptives (OC) have been shown to give a transient increased breast cancer risk. However, studies on breast cancer survival after OC use are sparse and conflicting.Aim: The aim of this study was to examine previous use of OC in relation to survival after breast cancer diagnosis.Methods: Data was collected from Malmö Diet and Cancer Study, with baseline examinations between