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The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype. peerReviewed

We consider a double-phase non-Newtonian fluid, described by a stress tensor which is the sum of a p-Stokes and a q-Stokes stress tensor, with 1 pqp, q), we prove the uniqueness of small solutions. We use the p q > 2 to justify calculations for weak solutions. Results are obtained through a careful use of the symmetries of the convective term and are also valid for rather general (even anisotropic) stress-tensors.

Bu çalışmanın amacı, ceviz (Juglans regia L.) bitkisinde 'Paradox' anaç çeşidine ait nod eksplant kökenli in vitro çoğaltım için farklı kültür tiplerinin (yarı katı, sıvı ve çift-fazlı) etkilerinin belirlenmesi ve mikroçoğaltım için gerekli tüm basamakların gerçekleştirilerek etkili bir mikroçoğaltım protokolünün oluşturulmasıdır. Çalışmanın ilk aşamasında uygun sterilizasyon yöntemini belirlemek amacıyla, Ulu Ceviz firmasından temin edilen nod eksplantları, farklı sterilizasyon yöntemlerine maruz bırakıldıktan sonra DKW (Driver and Kuniyuki, 1984) ve Rugini (Rugini, 1984) temelli yarı katı besin ortamlarında kültüre alınmışlardır. En etkili sterilizasyon yöntemi olan ST2 yöntemiyle, 15 dk deterjanlı su ve arkasından 15 dk akar su altında bekletilen eksplantlar, kabin içerisine alınarak 5 dk %70 alkol uygulandıktan sonra 5 dk birkaç damla Tween 20 ilave edilmiş %0,2 HgCl2 içerisinde çalkalanmıştır. Daha sonra üç defa steril sudan geçirilerek otoklavlanmış besin ortamlarına transfer edilmişlerdir. Bu sterilizasyon işlemi, eksplantlarda en az kararmanın (%4) gözlemlendiği yöntem olarak belirlenmiştir. Çalışmanın ikinci aşamasında yüzey sterilizasyonu sağlanan nod eksplantlarından sürgün indüksiyonu ve çoğaltımını gerçekleştirmek amacıyla, farklı bitki büyüme düzenleyicilerinin (IBA ve BAP) ve farklı kimyasal bileşiklerin (adenin hemisülfat ve kazein hidrolizat) kullanıldığı farklı besin ortamlarında (DKW, Rugini, Modifiye Rugini), farklı kültür tiplerinde (yarı katı, sıvı, çift-fazlı) kültüre alınmışlardır. Çalışmada elde edilen sonuçlara göre, birim eksplant başına düşen en yüksek sürgün sayısı (1,05 sürgün/eksplant) yarı katı SP4 (4 mg/L BAP+ 0.001 mg/L IBA + 200 mg/L kazein hidrolizat+ 50 mg/L adenin hemisülfat içeren DKW) besin ortamında elde edilmiştir. Ayrıca birim eksplant başına düşen ortalama nod sayısı (7,95 adet/eksplant) ve ortalama sürgün uzunluğu (1,6 cm) bakımından en başarılı ortam yarı katı SP2 (2 mg/L BAP + 0.001 mg/L IBA+ 200 mg/L kazein hidrolizat+ 50 mg/L adenin hemisülfat içeren DKW) olmuştur. Çalışmanın üçüncü aşamasında çoğaltımı gerçekleştirilen sürgün eksplantlarının köklendirilmesi amacıyla iki aşamalı bir in vitro köklendirme işlemi gerçekleştirilmiştir. Köklendirme çalışmasının ilk aşaması olan kök indüksiyonu için; sürgün eksplantları, farklı sükroz konsantrasyonlarının (30 ve 40 g/L) ve FeEDDHA (119 mg/L)'nın denenmesi amacıyla 4 mg/L IBA içeren farklı yarı katı besin ortamlarında (Modifiye MS, ½ Modifiye MS, Modifiye DKW, ½ Modifiye DKW) 7 gün boyunca karanlık koşullar altında kültüre alınmışlardır. Çalışmadan elde edilen sonuçlara göre en iyi kök indüksiyonu; 4 mg/L IBA içeren Modifiye yarı güç MS ortamında sağlanmıştır. Kök indüksiyonu gerçekleştirilen sürgün eksplantları daha sonra kök oluşumunun ve uzamasının sağlanması amacıyla; jelleştirici ajan olarak 2.4 mg/L Gelrite içeren, hormonsuz ve vermikulit ile karıştırılan (1:1 h/h) farklı besin ortamlarında (Modifiye DKW, ½ Modifiye DKW) 21 gün boyunca 16 saatlik fotoperiyotta (3500 lüks) kültüre alınmıştır. Kök oluşumu için en etkili ortam DKW temelli ¼ DFe olarak belirlenmiş ve %45,45 köklendirme oranı elde edilmiştir. Araştırmamızda, sıvı ve çift-fazlı besin ortamlarında kültüre alınan eksplantlar kararma ve kontaminasyon nedeniyle kaybedilmiştir. Sürgün rejenerasyonu ve köklenme bakımından yarı katı besin ortamları daha başarılı bulunmuştur., The aim of this study is to determine the effects of different culture types (semi solid, liquid, double-phase) and to create an effective micropropagation protocol performing all the steps required for in vitro reproduction of nodal explant origin in "Paradox" rootstock cultivar in walnut (Juglans regia L.) plant. In the first phase of the study, in order to determine the appropriate sterilization method, nodal explants obtained from Ulu Ceviz company were cultured in DKW (Driver and Kuniyuki, 1984) and Rugini (Rugini, 1984) based nutrient semi solid media after exposure to different sterilization methods. With the ST2 method, which is the most effective sterilization method, explants kept in detergent water for 15 minutes and then under running water for 15 minutes and then taken into the cabin and 70% alcohol was applied for 5 minutes, and after, shaked for 5 minutes with 0.2% HgCl2 added a few drops of Tween 20. Later, it was passed through sterile water three times and transferred to autoclaved nutrient media. This sterilization method was determined as the method in which the least blackening (4%) observed in the explants. In the second stage of the study, different plant growth regulators (IBA and BAP) and different chemical compounds (adenine hemisulphate and casein hydrolyzate) were used in different nutrient media (DKW, Rugini, Modified Rugini) and different culture types (semi solid, liquid, double-phase) in order to perform shoot induction and production from node explants with surface sterilization. According to the results obtained in the study, the highest number of shoot per unit (1.05 shoots / explant) was obtained in semi solid SP4 (4 mg/L BAP + 0.001 mg/L IBA + 200 mg/L casein hydrolyzate + 50 mg/L adenine hemisulphate containing DKW) in nutrient medium. In addition, the most successful medium in terms of the the avarege number of nodes per explant (7.95 nodes / explant) and avarage shoot length (1.6 cm) was semi solid SP2 (DKW with 2 mg/L BAP + 0.001 mg/L IBA + 200 mg/L casein hydrolyzate + 50 mg / L adenine hemisulphate). In the third stage of the study, a two-step in vitro rooting process was carried out in order to root of shoot explants produced. For root induction, which is the first stage of rooting study; shoot explants were cultured in different semi solid nutrient media containing 4 mg/L IBA (Modified MS, Modified MS, Modified DKW, ½ Modified DKW) to test the effect of different sucrose concentrations (30 and 40 g / L) and FeEDDHA (119 mg / L) under dark conditions during the 7 day. According to the results from the study, the best root induction was provided from half strength Modified MS medium with 4 mg/L IBA. Shoot explants, which root induction was performed, later in order to ensure root formation and elongation were cultured in different nutrient media (Modified DKW, ½ Modified DKW) containing 2.4 mg/L Gelrite as a gelling agent, without hormones and mixed with vermiculite (1:1 v/v) for 21 days in a 16-hour photoperiod (3500 lux). The most effective medium for root formation rate (45.45%) was determined as DKW based ¼ DFe. In our study, explants that were cultured in liquid and double-phase nutrient media were lost due to browning and contamination. Semi-solid nutrient media were found more successful in terms of shoot regeneration and rooting.

The DarkSide-50 experiment at the Laboratori Nazionali del Gran Sasso is a search for dark matter using a dual phase time projection chamber with 50 kg of low radioactivity argon as target. Light signals from interactions in the argon are detected by a system of 38 photo-multiplier tubes (PMTs), 19 above and 19 below the TPC volume inside the argon cryostat. We describe the electronics which processes the signals from the photo-multipliers, the trigger system which identifies events of interest, and the data-acquisition system which records the data for further analysis. The electronics include resistive voltage dividers on the PMTs, custom pre-amplifiers mounted directly on the PMT voltage dividers in the liquid argon, and custom amplifier/discriminators (at room temperature). After amplification, the PMT signals are digitized in CAEN waveform digitizers, and CAEN logic modules are used to construct the trigger, the data acquisition system for the TPC is based on the Fermilab "artdaq" software. The system has been in operation since early 2014., 24 pages

Purpose. To find out if single-photon emission computed tomography (SPECT) and I-123-subtraction can enhance the findings of Tc-99-methoxyisobutylisonitrile (MIBI) scintigraphy for the preoperative localization of parathyroid (PT) tumors.Methods. Among the 111 consecutive patients who underwent preoperative planar Tc-99-MIBI scintigraphy for hyperparathyroidism (HPT), 64 underwent delayed SPECT, and 17 underwent I-123-subtraction. Two independent blinded experts scored the topographical localization, diagnostic confidence, and impact of each diagnostic modality on the surgical strategy.Results. For adenomas, Tc-99-MIBI scintigraphy had a sensitivity of 77% with a positive predictive value (PPV) of 83%. SPECT did not affect the sensitivity or PPV, but it increased the diagnostic confidence and changed the surgical strategy in 21% of the patients. I-123-subtraction increased the sensitivity from 64% to 82%, but decreased the PPV from 88% to 82%. In hyperplastic glands, Tc-99-MIBI scintigraphy had a sensitivity of 47% and a PPV of 95%. When Tc-99-MIBI scintigraphy was combined with SPECT and I-123-subtraction, the results were 44%/10% and 52%/92%, respectively. Both SPECT and I-123-subtraction decreased the diagnostic confidence.Conclusions. Adding SPECT to Tc-99-MIBI scintigraphy improved the surgical decision for parathyroid adenomas. The addition of I-123-subtraction was of limited value. For hyperplastic glands, Tc-99-MIBI scintigraphy was relatively ineffective, even with the addition of SPECT or I-123-subtraction.