Dynamic range extension of SiPM detectors with the time-gated operation

The silicon photomultiplier (SiPM) is a novel detector technology that has undergone a fast development in the last few years, owing to its single-photon resolution and ultra-fast response time. However, the typical high dark count rates of the sensor may prevent the detection of low intensity radiation fluxes. In this article, the time-gated operation with short active periods in the nanosecond range is proposed as a solution to reduce the number of cells fired due to noise and thus increase the dynamic range. The technique is aimed at application fields that function under a trigger command, such as gated fluorescence lifetime imaging microscopy.

Impact of platelet rich plasma and adipose stem cells on lymphangiogenesis in a murine tail lymphedema model.

BACKGROUND: Lymphedema is an underdiagnosed pathology which in industrialized countries mainly affects cancer patients that underwent lymph node dissection and/or radiation. Currently no effective therapy is available so that patients' life quality is compromised by swellings of the concerned body region. This unfortunate condition is associated with body imbalance and subsequent osteochondral deformations and impaired function as well as with an increased risk of potentially life threatening soft tissue infections. METHODS: The effects of PRP and ASC on angiogenesis (anti-CD31 staining), microcirculation (Laser Doppler Imaging), lymphangiogenesis (anti-LYVE1 staining), microvascular architecture (corrosion casting) and wound healing (digital planimetry) are studied in a murine tail lymphedema model. RESULTS: Wounds treated by PRP and ASC healed faster and showed a significantly increased epithelialization mainly from the proximal wound margin. The application of PRP induced a significantly increased lymphangiogenesis while the application of ASC did not induce any significant change in this regard. CONCLUSIONS: PRP and ASC affect lymphangiogenesis and lymphedema development and might represent a promising approach to improve regeneration of lymphatic vessels, restore disrupted lymphatic circulation and treat or prevent lymphedema alone or in combination with currently available lymphedema therapies.

Alternatively spliced proline-rich cassettes link WNK1 to aldosterone action.

The thiazide-sensitive NaCl cotransporter (NCC) is important for renal salt handling and blood-pressure homeostasis. The canonical NCC-activating pathway consists of With-No-Lysine (WNK) kinases and their downstream effector kinases SPAK and OSR1, which phosphorylate NCC directly. The upstream mechanisms that connect physiological stimuli to this system remain obscure. Here, we have shown that aldosterone activates SPAK/OSR1 via WNK1. We identified 2 alternatively spliced exons embedded within a proline-rich region of WNK1 that contain PY motifs, which bind the E3 ubiquitin ligase NEDD4-2. PY motif-containing WNK1 isoforms were expressed in human kidney, and these isoforms were efficiently degraded by the ubiquitin proteasome system, an effect reversed by the aldosterone-induced kinase SGK1. In gene-edited cells, WNK1 deficiency negated regulatory effects of NEDD4-2 and SGK1 on NCC, suggesting that WNK1 mediates aldosterone-dependent activity of the WNK/SPAK/OSR1 pathway. Aldosterone infusion increased proline-rich WNK1 isoform abundance in WT mice but did not alter WNK1 abundance in hypertensive Nedd4-2 KO mice, which exhibit high baseline WNK1 and SPAK/OSR1 activity toward NCC. Conversely, hypotensive Sgk1 KO mice exhibited low WNK1 expression and activity. Together, our findings indicate that the proline-rich exons are modular cassettes that convert WNK1 into a NEDD4-2 substrate, thereby linking aldosterone and other NEDD4-2-suppressing antinatriuretic hormones to NCC phosphorylation status.

Solution equilibria of cytosine- and guanine-rich sequences near the promoter region of the n-myc gene that contain stable hairpins within lateral loops

Cytosine-and guanine-rich regions of DNA are capable of forming complex structures named i-motifs and G-quadruplexes, respectively. In the present study the solution equilibria at nearly physiological conditions of a 34 -bases long cytosine-rich sequence and its complementary guanin e-rich strand corresponding to the first intron of the n-mycgene were studied. Both sequences , not yet studied, contain a 12 - base tract capable of forming stable hairpins inside the i-motif and G-quadruplex structures, respectively ...

Effects of vacancy-type defects in silicon based particle detectors

The semiconductor particle detectors used at CERN experiments are exposed to radiation. Under radiation, the formation of lattice defects is unavoidable. The defects affect the depletion voltage and leakage current of the detectors, and hence affect on the signal-to-noise ratio of the detectors. This shortens the operational lifetime of the detectors. For this reason, the understanding of the formation and the effects of radiation induced defects is crucial for the development of radiation hard detectors. In this work, I have studied the effects of radiation induced defects-mostly vacancy related defects-with a simulation package, Silvaco. Thus, this work essentially concerns the effects of radiation induced defects, and native defects, on leakage currents in particle detectors. Impurity donor atom-vacancy complexes have been proved to cause insignificant increase of leakage current compared with the trivacancy and divacancy-oxygen centres. Native defects and divacancies have proven to cause some of the leakage current, which is relatively small compared with trivacancy and divacancy-oxygen.

Are we modular lying cues detectors ? The answer is "yes sometimes"

We quickly form first impressions about newly encountered people guiding our subsequent behaviour (approach, avoidance). Such instant judgments might be innate and automatic, being performed unconsciously and independently to other cognitive processes. Lying detection might be subject to such a modular process. Unfortunately, numerous studies highlighted problems with lying detection paradigms such as high error rates and learning effects. Additionally, humans should be motivated doing both detecting others' lies and dis- guising own lies. Disguising own lies might even be more challenging than detecting other people's lies. Thus, when trying to disguise cheating behaviour, liars might display a mixture of disguising (fake) trust cues and uncontrolled lying cues making the interpretation of the expression difficult (perceivers are guessing). In two consecutive online studies, we tested whether seeing an increasing amount (range 0-4) of lying cues (LC) and non-lying cues (NLC) on a standard face results in enhanced guessing behaviour (studies 1 and 2) and that enhanced guessing is accompanied by slower responding (study 2). Results showed that pronounced guessing and slowest responding occurred for faces with an intermediate number and not with the highest number of LC and NLC. In particular, LC were more impor- tant than NLC to uncertain lying decisions. Thus, only a few LC may interfere with automatic processing of lying detection (irrespective of NLC), probably because too little lying cue information is yet available.

Mind the Gap. Do Proportional Electoral Systems Foster a More Equal Representation of Women and Men, Poor and Rich ?

Female gender and low income are two markers for groups that have been historically disadvantaged within most societies. The study explores two research questions related to their political representation: 1) Are parties ideologically biased towards the ideological preferences of male and rich citizens? 2) Does the proportionality of the electoral system moderate the degree of underrepresentation of women and poor citizens in the party system? A multilevel analysis of survey data from 24 parliamentary democracies indicates that there is some bias against those with low income and, at a much smaller rate, women. This has systemic consequences for the quality of representation, as the preferences of the complementary groups differ. The proportionality of the electoral system influences the degree of underrepresentation: specifically, larger district magnitudes help closing the considerable gap between rich and poor.

Simulations of 3D Stripixel Detectors

Large Hadron Collider (LHC) is the main particle accelerator at CERN. LHC is created with main goal to search elementary particles and help science investigate our universe. Radiation in LHC is caused by charged particles circular acceleration, therefore detectors tracing particles in existed severe conditions during the experiments must be radiation tolerant. Moreover, further upgrade of luminosity (up to 1035 cm-2s-1) requires development of particle detector’s structure. This work is dedicated to show the new type 3D stripixel detector with serious structural improvement. The new type of radiation-hard detector has a three-dimensional (3D) array of the p+ and n+ electrodes that penetrate into the detector bulk. The electrons and holes are then collected at oppositely biased electrodes. Proposed 3D stripixel detector demonstrates that full depletion voltage is lower that that for planar detectors. Low depletion voltage is one of the main advantages because only depleted part of the device is active are. Because of small spacing between electrodes, charge collection distances are smaller which results in high speed of the detector’s response. In this work is also briefly discussed dual-column type detectors, meaning consisting both n+ and p+ type columnar electrodes in its structure, and was declared that dual-column detectors show better electric filed distribution then single sided radiation detectors. The dead space or in other words low electric field region in significantly suppressed. Simulations were carried out by using Atlas device simulation software. As a simulation results in this work are represented the electric field distribution under different bias voltages.

Amphotericin B associated with triglyceride-rich nanoemulsion: stability studies and in vitro antifungal activity

Amphotericin B (AB) is the standard drug for invasive fungal infection therapy. It has a broad spectrum of activity and it is the best antifungal available against most yeasts and molds. Its therapeutic use, however, is limited by significant side effects, leading to a low therapeutic index when it is used as the traditional formulation (Fungizone®). Due to self-association, AB can form pores in cholesterol-containing membranes. We propose a triglyceride-rich nanoemulsion as a delivery system for AB in low levels of aggregation to reduce the toxicity against host cells.

Readout electronics for low dark count pixel detectors based on geiger mode avalanche photodiodes fabricated in conventional CMOS technologies for future linear colliders

The high sensitivity and excellent timing accuracy of Geiger mode avalanche photodiodes makes them ideal sensors as pixel detectors for particle tracking in high energy physics experiments to be performed in future linear colliders. Nevertheless, it is well known that these sensors suffer from dark counts and afterpulsing noise, which induce false hits (indistinguishable from event detection) as well as an increase of the necessary area of the readout system. In this work, we present a comparison between APDs fabricated in a high voltage 0.35 µm and a high integration 0.13 µm commercially available CMOS technologies that has been performed to determine which of them best fits the particle collider requirements. In addition, a readout circuit that allows low noise operation is introduced. Experimental characterization of the proposed pixel is also presented in this work.

Singlet oxygen reactivity in water-rich solvent mixtures

The 3-methylindole (3MI) oxygenation sensitized by psoralen (PSO) has been investigated in 100%, 20% and 5% O2-saturated water/dioxane (H2O/Dx) mixtures. The lowering of the ¹O2* chemical rate when water (k chem∆3MI = 1.4 × 109 M-1 s-1) is replaced by deuterated water (k chem∆3MI = 1.9 × 108 M-1 s-1) suggests that hydrogen abstraction is involved in the rate determining step. A high dependence of the chemical rate constant on water concentration in H2O/Dx mixtures was found showing that water molecules are absolutely essential for the success of the 3MI substrate oxidation by ¹O2* in water-rich solvent mixtures.

The use of Rich and Suter diagrams to explain the electron configurations of transition elements

Rich and Suter diagrams are a very useful tool to explain the electron configurations of all transition elements, and in particular, the s¹ and s0 configurations of the elements Cr, Cu, Nb, Mo, Ru, Rh, Pd, Ag, and Pt. The application of these diagrams to the inner transition elements also explains the electron configurations of lanthanoids and actinoids, except for Ce, Pa, U, Np, and Cm, whose electron configurations are indeed very special because they are a mixture of several configurations.

Dft theoretical study of energetic nitrogen-rich C4N6H8-n(NO2)n derivatives

Density functional theory (DFT) calculations at the B3LYP/6-31G** theoretical level were performed for a series of guanidine-fused bicyclic skeleton derivatives C4N6H8-n(NO2)n (n = 1 - 6). The heats of formation (HOFs) were calculated by isodesmic reactions, and the detonation properties were evaluated using the Kamlet - Jacobs equations. The bond dissociation energies were also analyzed to investigate the thermal stability and sensitivity of the compounds. The results show that all of the derivatives have high positive HOFs, compound G has the highest theoretical density, and compound F1 has the highest detonation velocity and detonation pressure. Considering both the detonation properties and thermal stabilities, compounds D1 and D4 (3 nitro substituents), E1 - E6 (4 nitro substituents), and G (6 nitro substituents) can be regarded as potential candidates for high-energy density materials.