Although the bottom blowing ShuiKouShan process has now been widely implemented in China, in both lead and copper smelters, some doubts, questions, and concerns still seem to prevail in the ...metallurgical community outside China. In the author’s opinion, part of these doubts and concerns could be addressed by a better general understanding of key concepts of submerged gas injection, including gas jet trajectory and penetration, and the concept, application, and benefits of sonic injection in jetting regime. To provide some answers, this article first offers a discussion on the historical developments of the theory and mathematical characterization of submerged gas jet trajectory, including the proposed criteria for the transition from bubbling to jetting regime and the application of the Prandtl–Meyer theory to submerged gas jets. A second part is devoted to a quantitative study of submerged gas jet penetration in copper bath smelting, including a comparison between bubbling and jetting regimes, and side versus bottom blowing. In the specific cases studied, the calculated gas jet axis trajectory length in jetting regime is 159 cm for bottom blowing, whereas it varies between 129 and 168 cm for side blowing for inclination angles of +18° to −30° to the horizontal. This means that side blowing in the jetting regime would provide a deeper penetration and longer gas jet trajectory than generally obtained by conventional bath smelting vessels such as the Noranda and Teniente reactors. The theoretical results of this study do corroborate the successful high-intensity practice of the slag make converting process at Glencore Nickel in Canada that operates under high oxygen shrouded injection in the jetting regime, and this would then suggest that retrofitting conventional low-pressure, side-blowing tuyeres of bath smelting and converting reactors with sonic injectors in jetting regime certainly appears as a valuable option for process intensification with higher oxygen enrichment, without major process changes or large capital expenditure, i.e., no need for full reactor replacement.
High spatial resolution monolithic pixel detector in SOI technology Bugiel, R.; Bugiel, S.; Dannheim, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2021, Volume:
988
Journal Article
Peer reviewed
Open access
This paper presents test-beam results of monolithic pixel detector prototypes fabricated in 200 nm Silicon-On-Insulator (SOI) CMOS technology studied in the context of high spatial resolution ...performance. The tested detectors were fabricated on a 500 μm thick high-resistivity Floating Zone type n (FZ-n) wafer and on a 300 μm Double SOI Czochralski type p (DSOI Cz-p) wafer. The pixel size is 30 μm×30 μm and two different front-end electronics architectures were tested, a source follower and a charge-sensitive preamplifier. The test-beam data analyses were focused mainly on determination of the spatial resolution and the hit detection efficiency. In this work different cluster formation and position reconstruction methods are studied. In particular, a generalization of the standard η-correction adapted for arbitrary cluster sizes, is introduced. The obtained results give in the best case a spatial resolution of about 1.5 μm for the FZ-n wafer and about 3.0 μm for the DSOI Cz-p wafer, both detectors showing detection efficiency above 99.5%.
Belle II is a new-generation B-factory experiment, dedicated to exploring new physics beyond the standard model of elementary particles in the flavor sector. Belle II started data-taking in April ...2018, using a synchronous data acquisition (DAQ) system based on pipelined trigger flow control. The Belle II DAQ system is designed to handle a 30-kHz trigger rate with approximately 1% of dead time, under the assumption of a raw event size of 1 MB. The DAQ system is reliable, and the overall data-taking efficiency reached 84.2% during the run period of January 2020-June 2020. The current readout system cannot be operated in the terms of ten years from the viewpoint of DAQ maintainability; meanwhile, the readout system is obstructing high-speed data transmission. A solution involving a peripheral component interconnect (PCI)-express-based readout module with high data throughput of up to 100 Gb/s was adopted to upgrade the Belle II DAQ system. We particularly focused on the design of firmware and software based on this new generation of readout board, called PCIe40, with an Altera Arria 10 field-programmable gate array chip. The 48-Gb transceiver (GBT) serial links, PCI-express hard IP-based direct memory access (DMA) architecture, interface of timing and trigger distribution system, and slow control system were designed to integrate with the current Belle II DAQ system. This article describes the performances accomplished during the data readout and slow control tests conducted using a test bench and a demonstration performed using on-site front-end electronics, specifically involving Belle II TOP and KLM subdetectors.
The Belle II experiment and the SuperKEKB collider are designed to operate under a higher luminosity compared to that of Belle for the improvement of rare <inline-formula> <tex-math ...notation="LaTeX">B </tex-math></inline-formula> meson decay study and new physics search. To break the bottleneck of bandwidth and to improve the stability in the operation of the Belle II data acquisition (DAQ) system, a new PCI-express-based readout system has been developed. The new system includes a PCI-express-based high-speed readout board (PCIe40), which was originally developed for the upgrades of the LHCb and ALICE experiments, the PCIe40 firmware, the slow control, and readout software running on a readout PC. The new readout system's commissioning with most of the Belle II subdetectors has been performed, and the readout upgrade is complete for the particle-identification detectors and the neutral kaon and muon detector in Belle II, which has been operating stably with the new system in the beam collision "physics runs." The results of the commissioning and the performance of the global DAQ operation will be reported.
The silicon vertex detector of the Belle II experiment Irmler, C.; Adamczyk, K.; Aggarwal, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2023, Volume:
1045
Journal Article
Peer reviewed
Open access
The Belle II experiment is taking data at the asymmetric SuperKEKB collider (KEK, Japan), which operates at the Υ(4S) resonance. The vertex detector is composed of an inner two-layer pixel detector ...(PXD) and the silicon vertex detector (SVD), made of four layers of double-sided silicon strip detectors. A deep knowledge of the system has been gained since the start of operations in 2019 by assessing the high-quality and stable reconstruction performance of the detector. The very high hit efficiency and large signal-to-noise ratio are monitored via online data-quality plots. The good cluster-position resolution is estimated using the unbiased residual with respect to the track, and it is in reasonable agreement with the expectations. The SVD dose is estimated by the correlation of the SVD occupancy with the dose measured by the diamond sensors of the radiation-monitoring and beam-abort system. First radiation damage effects are measured on the sensor current and strip noise are shown not to affect the performance. Six samples of the shaped particle signal are recorded utilizing the multi-peak mode of the APV25 front-end chip and used to determine the hit timing with a precision of 2 to 3 ns. Recently a method to compute the time of collision from SVD hit time information has been implemented and verified with simulations and on data.
Purpose
Our insight in the genetics of Hashimoto’s thyroiditis (HT) has become clearer through information provided by genome-wide association studies and candidate gene studies, but remains still ...not fully understood. Our aim was to assess how many different genetic risk variants contribute to the development of HT.
Methods
147 HT cases (10.2% men) and 147 controls (13.6% men) were qualified for the analysis. Intrinsic and environmental factors were controlled for. Polymorphisms (SNP) were chosen based on the literature and included markers of the genes
PTPN22, CTLA4, TG, TPO
among others, and of genomic regions pointed by GWAS studies. SNP were typed on a microarray. Variants in the
HLA
-
DRB1
gene were identified by Sanger sequencing.
Results
Multivariate predisposition to HT was modeled. Based on the investigated group, a model of seven variables was obtained. The variability explained by this model was assessed at only 5.4821% (
p
= 2 × 10
−6
), which indicates that many dozens of factors are required simultaneously to explain HT predisposition.
Conclusions
We analyzed genetic regions commonly and most significantly associated with autoimmune thyroid disorders in the literature, on a carefully selected cohort. Our results indicated a lack of possibility to predict the risk of HT development, even with a multivariate model. We therefore conclude that strong associations of single genetic regions with HT should be interpreted with great caution. We believe that a change in the attitude towards genetic association analyses of HT predisposition is necessary. Studies including multiple factors simultaneously are needed to unravel the intricacies of genetic associations with HT.
Objective Negative pressure wound therapy (NPWT) has been used to treat diabetic foot ulcerations (DFUs). Its action on the molecular level, however, is only partially understood. Some earlier data ...suggested NPWT may be mediated through modification of local gene expression. As methylation is a key epigenetic regulatory mechanism of gene expression, we assessed the effect of NPWT on its profile in patients with type 2 diabetes (T2DM) and neuropathic non-infected DFUs. Methods Of 36 included patients, 23 were assigned to NPWT and 13 to standard therapy. Due to ethical concerns, the assignment was non-randomized and based on wound characteristics. Tissue samples were obtained before and 8 ± 1 days after therapy initiation. DNA methylation patterns were checked by Illumina Methylation EPIC kit. Results In terms of clinical characteristics, the groups presented typical features of T2DM; however, the NPWT group had significantly greater wound area: 16.8 cm2 vs 1.4 cm2 (P = 0.0003). Initially only one region at chromosome 5 was differentially methylated. After treatment, 57 differentially methylated genes were found, mainly located on chromosomes 6 (chr6p21) and 20 (chr20p13); they were associated with DNA repair and autocrine signaling via retinoic acid receptor. We performed differential analyses pre treatment and post treatment. The analysis revealed 426 differentially methylated regions in the NPWT group, but none in the control group. The enrichment analysis showed 11 processes significantly associated with NPWT, of which 4 were linked with complement system activation. All but one were hypermethylated after NPWT. Conclusion The NPWT effect on DFUs may be mediated through epigenetic changes resulting in the inhibition of complement system activation.
The Belle II silicon vertex detector is one of the vertex detectors in the Belle II experiment. The detector reads out the signals from the double-sided silicon strip sensors with the APV25 front-end ...readout ASIC, adopting the chip-on-sensor concept to minimize the strip noise. The detector has been operated in the experiment since the spring of 2019. Analyzing the acquired data during the beam collisions, the excellent performance of the detector is confirmed. Also, the radiation dose and 1-MeV equivalent neutron fluence of the detector are estimated using the measured dose rates of the diamond sensors installed on the beam pipe and are compared with the measured radiation effects in the strip noise, leakage current, and depletion voltage. This paper briefly introduces the main features of the silicon vertex detector, and then reports on the measured performance and radiation effects of the first two years of running experience of the detector.
Violets of the sections Melanium were examined for their colonization by arbuscular mycorrhizal fungi (AMF). Heartsease (
Viola tricolor) from several heavy metal soils was AMF-positive at many sites ...but not at extreme biomes. The zinc violets
Viola lutea ssp.
westfalica (blue zinc violet) and ssp.
calaminaria (yellow zinc violet) were always AMF-positive on heavy metal soils as their natural habitats. As shown for the blue form, zinc violets germinate independently of AMF and can be grown in non-polluted garden soils. Thus the zinc violets are obligatorily neither mycotrophs nor metalophytes. The alpine
V. lutea, likely ancestor of the zinc violets, was at best poorly colonized by AMF. As determined by atomic absorption spectrometry, the contents of Zn and Pb were lower in AMF colonized plants than in the heavy metal soils from where the samples had been taken. AMF might prevent the uptake of toxic levels of heavy metals into the plant organs. Dithizone staining indicated a differential deposition of heavy metals in tissues of heartsease. Leaf hairs were particularly rich in heavy metals, indicating that part of the excess of heavy metals is sequestered into these cells.
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