Hasil untuk "physics.atm-clus"

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S2 Open Access 2011
Common variants in MS4A4/MS4A6E, CD2uAP, CD33, and EPHA1 are associated with late-onset Alzheimer’s disease

A. Naj, G. Jun, G. Beecham et al.

The Alzheimer Disease Genetics Consortium (ADGC) performed a genome-wide association study of late-onset Alzheimer disease using a three-stage design consisting of a discovery stage (stage 1) and two replication stages (stages 2 and 3). Both joint analysis and meta-analysis approaches were used. We obtained genome-wide significant results at MS4A4A (rs4938933; stages 1 and 2, meta-analysis P (PM) = 1.7 × 10−9, joint analysis P (PJ) = 1.7 × 10−9; stages 1, 2 and 3, PM = 8.2 × 10−12), CD2AP (rs9349407; stages 1, 2 and 3, PM = 8.6 × 10−9), EPHA1 (rs11767557; stages 1, 2 and 3, PM = 6.0 × 10−10) and CD33 (rs3865444; stages 1, 2 and 3, PM = 1.6 × 10−9). We also replicated previous associations at CR1 (rs6701713; PM = 4.6 × 10−10, PJ = 5.2 × 10−11), CLU (rs1532278; PM = 8.3 × 10−8, PJ = 1.9 × 10−8), BIN1 (rs7561528; PM = 4.0 × 10−14, PJ = 5.2 × 10−14) and PICALM (rs561655; PM = 7.0 × 10−11, PJ = 1.0 × 10−10), but not at EXOC3L2, to late-onset Alzheimer's disease susceptibility.

1877 sitasi en Medicine, Biology
S2 Open Access 2019
Robust, Highly Luminescent Au13 Superatoms Protected by N-Heterocyclic Carbenes.

Mina R. Narouz, Shinjiro Takano, P. Lummis et al.

Gold superatom nanoclusters stabilized entirely by N-heterocyclic carbenes (NHCs) are reported. The reduction of well-defined NHC-Au-Cl complexes produces clusters com-prised of an icosahedral Au13 core surrounded by a symmetrical arrangement of 9 NHCs and 3 chlorides. X-ray crystallography shows that the clusters are characterized by multiple CH-π and π-π interactions, which rigidify the ligand and likely con-tribute to the exceptionally high photoluminescent quantum yields observed, up to 16.0 %, which is significantly greater than the most luminescent ligand-protected Au13 superatom cluster. Density functional theory analysis suggests that clus-ters are 8-electron superatoms with a wide HOMO-LUMO energy gap of 2 eV. Consistent with this, the clusters have high stability relative to all-phosphine clusters.

179 sitasi en Medicine, Chemistry
arXiv Open Access 2023
Size distributions in irreversible particle aggregation

Klavs Hansen

The aggregation of particles in the free molecular regime is determined approximately for situations with a high degree of translational energy equilibration. The mean particle sizes develop linearly in time. Scaling relations are used to derive a linear partial differential equation which is solved to show that the size distributions are close to log-normal asymptotically in time.

en physics.atm-clus
S2 Open Access 2022
A modified lung ultrasound score to evaluate short-term clinical outcomes of bronchopulmonary dysplasia

Yinghua Sun, Yang Du, Jie Shen et al.

Background Lung ultrasound (LUS) is a useful tool for assessing the severity of lung disease, without radiation exposure. However, there is little data on the practicality of LUS in assessing the severity of bronchopulmonary dysplasia (BPD) and evaluating short-term clinical outcomes. We adapted a LUS score to evaluate BPD severity and assess the reliability of mLUS score correlated with short-term clinical outcomes. Methods Prospective diagnostic accuracy study was designed to enroll preterm infants with gestational age < 34 weeks. Lung ultrasonography was performed at 36 weeks postmenstrual age. The diagnostic and predictive values of new modified lung ultrasound (mLUS) scores based on eight standard sections were compared with classic lung ultrasound (cLUS) scores. Results A total of 128 infants were enrolled in this cohort, including 30 without BPD; 31 with mild BPD; 23 with moderate BPD and 44 with severe BPD. The mLUS score was significantly correlated with the short-term clinical outcomes, superior to cLUS score. The mLUS score well correlated with moderate and severe BPD (AUC = 0.813, 95% CI 0.739–0.888) and severe BPD (AUC = 0.801, 95% CI 0.728–0.875), which were superior to cLUS score. The ROC analysis of mLUS score to evaluate the other short-term outcomes also showed significant superiority to cLUS score. The optimal cutoff points for mLUS score were 14 for moderate and severe BPD and 16 for severe BPD. Conclusions The mLUS score correlates significantly with short-term clinical outcomes and well evaluates these outcomes in preterm infants.

17 sitasi en Medicine
S2 Open Access 2022
An Accurate and Hardware-Efficient Dual Spike Detector for Implantable Neural Interfaces

Xiaorang Guo, MohammadAli Shaeri, Mahsa Shoaran

Spike detection plays a central role in neural data processing and brain-machine interfaces (BMIs). A challenge for future-generation implantable BMIs is to build a spike detector that features both low hardware cost and high performance. In this work, we propose a novel hardware-efficient and high-performance spike detector for implantable BMIs. The proposed design is based on a dual-detector architecture with adaptive threshold estimation. The dual-detector comprises two separate TEO-based detectors that distinguish a spike occurrence based on its discriminating features in both high and low noise scenarios. We evaluated the proposed spike detection algorithm on the Wave Clus dataset. It achieved an average detection accuracy of 98.9%, and over 95% in high-noise scenarios, ensuring the reliability of our method. When realized in hardware with a sampling rate of 16kHz and 7-bits resolution, the detection accuracy is 97.4%. Designed in 65nm TSMC process, a 256-channel detector based on this architecture occupies only 682µm2/Channel and consumes 0.07µW/Channel, improving over the state-of-the-art spike detectors by 39.7% in power consumption and 78.8% in area, while maintaining a high accuracy.

14 sitasi en Computer Science, Engineering
S2 Open Access 2018
The Use of Virtual Reality in Patients with Eating Disorders: Systematic Review

Damien Clus, M. Larsen, C. Lemey et al.

Background Patients with eating disorders are characterized by pathological eating habits and a tendency to overestimate their weight and body shape. Virtual reality shows promise for the evaluation and management of patients with eating disorders. This technology, when accepted by this population, allows immersion in virtual environments, assessment, and therapeutic approaches, by exposing users to high-calorie foods or changes in body shape. Objective To better understand the value of virtual reality, we conducted a review of the literature, including clinical studies proposing the use of virtual reality for the evaluation and management of patients with eating disorders. Methods We searched PubMed, PsycINFO, ScienceDirect, the Cochrane Library, Scopus, and Web of Science up to April 2017. We created the list of keywords based on two domains: virtual reality and eating disorders. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses to identify, select, and critically appraise relevant research while minimizing bias. Results The initial database searches identified 311 articles, 149 of which we removed as duplicates. We analyzed the resulting set of 26 unique studies that met the inclusion criteria. Of these, 8 studies were randomized controlled trials, 13 were nonrandomized studies, and 5 were clinical trials with only 1 participant. Most articles focused on clinical populations (19/26, 73%), with the remainder reporting case-control studies (7/26, 27%). Most of the studies used visual immersive equipment (16/26, 62%) with a head-mounted display (15/16, 94%). Two main areas of interest emerged from these studies: virtual work on patients’ body image (7/26, 27%) and exposure to virtual food stimuli (10/26, 38%). Conclusions We conducted a broad analysis of studies on the use of virtual reality in patients with eating disorders. This review of the literature showed that virtual reality is an acceptable and promising therapeutic tool for patients with eating disorders.

137 sitasi en Medicine, Psychology
S2 Open Access 2020
Variation in soil properties under different cropping and other land-use systems in Dura catchment, Northern Ethiopia

Gebreyesus Brhane Tesfahunegn, Teklebirhan Arefaine Gebru

There are limited reports about the impacts of long-term cropping and land-use systems (CLUS) on soil properties and nutrient stocks under smallholder farmers’ conditions in developing countries. The objective of this research was to examine variation in soil properties and OC and TN stocks across the different CLUS in Dura sub-catchment, northern Ethiopia. Surveys and discussions on field history were used to identify nine CLUS, namely, tef (Eragrostis tef (Zucc) Trot)) mono-cropping (TM), maize (Zea mays L.) mono-cropping (MM), cauliflower (Brassica oleracea var. botrytis)-maize intercropping (IC1), red beet (Beta Vulgaris)-maize intercropping (IC2), cauliflower-tef-maize rotation (R1), onion (Allium cepa L.)-maize-onion rotation (R2), tr eated gully (TG), untreated gully (UTG), and natural forest system (NF). A total of 27 composite soil samples were randomly collected from the CLUS for soil analysis. Data were subjected to one-way analysis of variance and PCA. The lowest and highest bulk density was determined from NF (1.19 Mg m-3) and UTG (1.77 Mg m-3), respectively. Soil pH, EC and CEC varied significantly among the CLUS. The highest CEC (50.3 cmolc kg-1) was reported under TG followed by NF. The highest soil OC stock (175.3 Mg C ha−1) and TN stock (13.6 Mg C ha−1) were found from NF. The PCA chosen soil properties explained 87% of the soil quality variability among the CLUS. Such soil properties and nutrient stocks variability among the CLUS suggested that introduction of suitable management practices that sustain the soil system of the CLUS with poor soil properties and nutrient stocks are crucial for the study area conditions.

53 sitasi en Medicine, Biology
S2 Open Access 2014
The SILCC (SImulating the LifeCycle of molecular Clouds) project – I. Chemical evolution of the supernova-driven ISM

S. Walch, P. Girichidis, T. Naab et al.

The SILCC (SImulating the Life-Cycle of molecular Clouds) project aims to self-consistently understand the small-scale structure of the interstellar medium (ISM) and its link to galaxy evolution. We simulate the evolution of the multiphase ISM in a (500 pc)2 × ±5 kpc region of a galactic disc, with a gas surface density of ΣGAS=10M⊙pc−2. The flash 4 simulations include an external potential, self-gravity, magnetic fields, heating and radiative cooling, time-dependent chemistry of H2 and CO considering (self-) shielding, and supernova (SN) feedback but omit shear due to galactic rotation. We explore SN explosions at different rates in high-density regions (peak), in random locations with a Gaussian distribution in the vertical direction (random), in a combination of both (mixed), or clustered in space and time (clus/clus2). Only models with self-gravity and a significant fraction of SNe that explode in low-density gas are in agreement with observations. Without self-gravity and in models with peak driving the formation of H2 is strongly suppressed. For decreasing SN rates, the H2 mass fraction increases significantly from <10 per cent for high SN rates, i.e. 0.5 dex above Kennicutt–Schmidt, to 70–85 per cent for low SN rates, i.e. 0.5 dex below KS. For an intermediate SN rate, clustered driving results in slightly more H2 than random driving due to the more coherent compression of the gas in larger bubbles. Magnetic fields have little impact on the final disc structure but affect the dense gas (n ≳ 10 cm−3) and delay H2 formation. Most of the volume is filled with hot gas (∼80 per cent within ±150 pc). For all but peak driving a vertically expanding warm component of atomic hydrogen indicates a fountain flow. We highlight that individual chemical species populate different ISM phases and cannot be accurately modelled with temperature-/density-based phase cut-offs.

242 sitasi en Physics
arXiv Open Access 2019
Weakly bound LiHe$_2$ molecules in the framework of three-dimensional Faddeev equations

E. A. Kolganova, V. Roudnev

A method of direct solution of the Faddeev equations for the bound-state problem with zero total angular momentum is used to calculate the binding energies. The results for binding energies of He$_2$$^6$Li and He$_2$$^7$Li systems and helium atom - HeLi dimer scattering length are presented. The results show that modern potential models support two bound states in both trimers. In both cases the energy of the excited state is very close to the energy of the lowest two-body threshold.

en physics.atm-clus
S2 Open Access 2017
Extracorporal Shock Waves Activate Migration, Proliferation and Inflammatory Pathways in Fibroblasts and Keratinocytes, and Improve Wound Healing in an Open-Label, Single-Arm Study in Patients with Therapy-Refractory Chronic Leg Ulcers

I. Aschermann, S. Noor, S. Venturelli et al.

Background/Aims: Chronic leg ulcers (CLUs) are globally a major cause of morbidity and mortality with increasing prevalence. Their treatment is highly challenging, and many conservative, surgical or advanced therapies have been suggested, but with little overall efficacy. Since the 1980s extracorporal shock wave therapy (ESWT) has gained interest as treatment for specific indications. Here, we report that patients with CLU showed wound healing after ESWT and investigated the underlying molecular mechanisms. Methods: We performed cell proliferation and migration assays, FACS- and Western blot analyses, RT-PCR, and Affymetrix gene expression analyses on human keratinocytes and fibroblasts, and a tube formation assay on human microvascular endothelial cells to assess the impact of shock waves in vitro. In vivo, chronic therapy-refractory leg ulcers were treated with ESWT, and wound healing was assessed. Results: Upon ESWT, we observed morphological changes and increased cell migration of keratinocytes. Cell-cycle regulatory genes were upregulated, and proliferation induced in fibroblasts. This was accompanied by secretion of pro-inflammatory cytokines from keratinocytes, which are known to drive wound healing, and a pro-angiogenic activity of endothelial cells. These observations were transferred “from bench to bedside”, and 60 consecutive patients with 75 CLUs with different pathophysiologies (e.g. venous, mixed arterial-venous, arterial) were treated with ESWT. In this setting, 41% of ESWT-treated CLUs showed complete healing, 16% significant improvement, 35% improvement, and 8% of the ulcers did not respond to ESWT. The induction of healing was independent of patient age, duration or size of the ulcer, and the underlying pathophysiology. Conclusions: The efficacy of ESWT needs to be confirmed in controlled trials to implement ESWT as an adjunct to standard therapy or as a stand-alone treatment. Our results suggest that EWST may advance the treatment of chronic, therapy-refractory ulcers.

45 sitasi en Medicine
CrossRef Open Access 2018
Silent Hypoglycemia in Patients with Diabetes

Simona Clus, Gabriela Creteanu, Amorin Popa

Abstract Introduction. Iatrogenic hypoglycemia increases cardiovascular morbidity sometimes even with fatalities, and also increases cognitive disorders in most people with type 1 diabetes (T1D) and type 2 diabetes (T2D). Hypoglycemia is characterized by unawareness if the sympathoadrenal response is attenuated during the night, in autonomic neuropathy or in elderly patients. Therefore, hypoglycemia is a limiting factor in the glycemic management of diabetes. Methods . We aimed to analyze the hypoglycemic events and the time spent with low glucose level (glucose <3.9 mmol/l) in patients with diabetes (T1D, T2D) with insulin therapy (basal or basal-bolus), in ambulatory or hospital setting. The glucose variability was assessed via the interstitial glucose concentration, measured with a Continuous Glucose Monitoring (CGM) system over 72 hours. Results. The incidence, severity and duration of hypoglycemia are not correlated with HbA1c, disease’s duration and patient’s age. In patients with T1D, severe hypoglycemia is more frequent in patients with a long duration of diabetes. In this analysis, the type of basal analog insulin did not influence the presence of hypoglycemia (p=0.7), but the duration of nocturnal hypoglycemia was longer with insulin glargine U100 than with insulin detemir. The basal regimen is more protective for hypoglycemia than basal-bolus insulin. Conclusions . The study suggested that hypoglycemic events are common, silent and prolonged in 1/3 of patients with T1D and T2D. The CGM system is beneficial for all patients with T1D and for patients with T2D with hypoglycemic risk and complications, to adjust medication in order to prevent cardiovascular events.

arXiv Open Access 2017
Hidden momentum of electrons, nuclei, atoms and molecules

Robert P. Cameron, J. P. Cotter

We consider the positions and velocities of electrons and spinning nuclei and demonstrate that these particles harbour hidden momentum when located in an electromagnetic field. This hidden momentum is present in all atoms and molecules, however it is ultimately cancelled by the momentum of the electromagnetic field. We point out that an electron vortex in an electric field might harbour a comparatively large hidden momentum and recognise the phenomenon of 'hidden hidden momentum'.

en physics.atm-clus

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