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In this paper, we provide a formalism for the characterization of tracking arrays with emphasis on the proper corrections required to extract their photopeak efficiencies and peak-to-total ratios. The methods are first applied to Gammasphere, a well characterized 4π array based on the principle of Compton suppression, and subsequently to GRETINA. The tracking efficiencies are then discussed and so

This work presents a digital calibration technique in continuous-time (CT) delta-sigma (Δ Σ) analog to digital converter. The converter is clocked at 144 MHz with a low oversampling ratio (OSR) of only 8. Dynamic element matching is not efficient to linearize the digital to analog converter (DAC) when the OSR is very low. Therefore, non-idealities in the outermost multi-bit feedback DAC are measur

Epigenetic variation in human adipose tissue has been linked to type 2 diabetes and its related risk factors including age and obesity. Insulin resistance, a key risk factor for type 2 diabetes, may also be associated with altered DNA methylation in visceral and subcutaneous adipose tissue. Furthermore, linking epigenetic variation in target tissues to similar changes in blood cells may identify n

Endocrine disrupting chemicals (EDCs) have the potential to affect development and reproduction in gastropods. However, one is today lacking basic understanding of the Molluscan endocrine system and one can therefore not fully explain these EDC-induced affects. Furthermore, only a few genes that potentially may be connected to the endocrine system have been sequenced in gastropods. An example is t

Cranial radiotherapy is a known risk factor for neurocognitive impairment in survivors of childhood acute lymphoblastic leukemia (ALL). Understanding the nature of cognitive dysfunction during adulthood in ALL survivors is important as it has an impact on major life situations. Thirty-eight (21 women) ALL survivors were investigated 34 years after diagnosis. Median-age was 38 (27–46) years. All we

•Apoptins are viral proteins that trigger cell death.•Apoptins show cancer-selective toxicity.•Potential delivery methods are being assayed for future apoptin clinical trials.Therapies that selectively target cancer cells for death have been the center of intense research recently. One potential therapy may involve apoptin proteins, which are able to induce apoptosis in cancer cells leaving normal

Introduction Anal fistula is an abnormal tract with an external and internal opening that cause leakage, discomfort, and occasionally pain. Surgery is standard treatment, but recurrence and anal incontinence is common. The objective of the study was to analyze resource use, costs and sick leave for newly diagnosed patients with anal fistula in Sweden. Methods The study was based on register data f

Population-based metaheuristic algorithms are powerful tools in the design of neutron scattering instruments and the use of these types of algorithms for this purpose is becoming more and more commonplace. Today there exists a wide range of algorithms to choose from when designing an instrument and it is not always initially clear which may provide the best performance. Furthermore, due to the nat

In order to properly design an absorption tower for CO2 capture knowledge on the absorption rate of CO2 is required. Several methods can be used to determine the absorption rate, such as a wetted wall column (WWC), stirred absorption cell or a string of discs setup. The aim of this work was to determine the absorption flux of CO2 into different amine solutions using anew method. Two absorption sys

Background Calcium imaging is based on the detection of minute signal changes in an image time-series encompassing pre- and post-stimuli. Depending on the function of the elicited response, change may be pronounced, as in the case of a genetically encoded calcium-reporter protein, or subtle, as is the case in a bath-applied dye system. Large datasets are thus often acquired and appraised only duri

The purpose of this study was to describe and analyse leadership challenges in the organisation of strategic research centres, focusing on the relationship between organisation and the level of institutionalisation. Four main themes of leadership challenges were identified: (1) the changing university context, including relationships with top management and faculties; (2) research strategy, consid

Hydrophobic resin acids (RAs) are synthesized by conifer trees as part of their defense mechanisms. One of the functions of RAs in plant defense is suggested to be the perturbation of the cellular membrane. However, there is a vast diversity of chemical structures within this class of molecules, and there are no clear correlations to the molecular mechanisms behind the RA's toxicity. In this study

Despite being one of Earth's major geochemical cycles, the evolution of the silicon cycle has received little attention and changes in oceanic dissolved silica (DSi) concentration through geologic time remain poorly constrained. Silicon isotope ratios (expressed as δ30Si) in marine microfossils are becoming increasingly recognised for their ability to provide insight into silicon cycling. In parti

Data were collected between 2011 and 2014 from five evacuations involving the same school buildings located in Spain. Children from 6 to 16 years of age were observed during the evacuation exercises. Background information was collected on key factors deemed to influence evacuation performance: a description of the geometry, the population involved, the procedures employed and the organization of

Fiber composites are widely used for space applications such as antennas, solar panels and spacecraft support structures. This paper presents a combined electromagnetic and acoustic analysis of a triaxial carbon fiber weave structure, designed for ultra lightweight reflector antennas in satellite communication systems. The electromagnetic and acoustic performance of the structure are analyzed over

The mechanism of ethylene polymerization on phenoxy-imine (FI) titanium catalysts was studied theoretically to identify the major factors affecting the catalytic activity. Geometry optimizations of FI ligands, octahedral titanium dichloride complexes, active cationic species, and their π‐complexes with ethylene as well as calculations of the energy profile of chain propagation were performed at th

The nucleotide (nt) sequences of the str operon in Escherichia coli K-12 and Salmonella typhimurium LT2 were completed and compared at the nt and amino acid (aa) level. The order of conservation at the nt and aa level is rpsL greater than tufA greater than rpsG greater than f usA. A striking difference is that the rpsG-encoded ribosomal protein, S7, in E. coli K-12 is 23 aa longer than in S. typhi