Development and Tests of PWM Amplifier for Driving the Piezoelectric Elements

The paper describes the design and research work carried out to prepare the prototype of pulse amplifier. The work was aimed to describe main operational parameters of PWM amplifiers enabling using them to control the piezoelectric actuators used for active compensation of Lorentz force detuning of superconducting cavities

Genetic and Environmental Determinants of Immune Response to Cutaneous Melanoma

The immune response to melanoma improves the survival in untreated patients and predicts the response to immune checkpoint blockade. Here, we report genetic and environmental predictors of the immune response in a large primary cutaneous melanoma cohort. Bioinformatic analysis of 703 tumor transcriptomes was used to infer immune cell infiltration and to categorize tumors into immune subgroups, which were then investigated for association with biological pathways, clinicopathologic factors, and copy number alterations. Three subgroups, with “low”, “intermediate”, and “high” immune signals, were identified in primary tumors and replicated in metastatic tumors. Genes in the low subgroup were enriched for cell-cycle and metabolic pathways, whereas genes in the high subgroup were enriched for IFN and NF-κB signaling. We identified high MYC expression partially driven by amplification, HLA-B downregulation, and deletion of IFNγ and NF-κB pathway genes as the regulators of immune suppression. Furthermore, we showed that cigarette smoking, a globally detrimental environmental factor, modulates immunity, reducing the survival primarily in patients with a strong immune response. Together, these analyses identify a set of factors that can be easily assessed that may serve as predictors of response to immunotherapy in patients with melanoma. Significance: These findings identify novel genetic and environmental modulators of the immune response against primary cutaneous melanoma and predict their impact on patient survival

Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

Transcriptomic Analysis Reveals Prognostic Molecular Signatures of Stage I Melanoma

Purpose: Previously identified transcriptomic signatures have been based on primary and metastatic melanomas with relatively few American Joint Committee on Cancer (AJCC) stage I tumors, given difficulties in sampling small tumors. The advent of adjuvant therapies has highlighted the need for better prognostic and predictive biomarkers, especially for AJCC stage I and stage II disease. Experimental Design: A total of 687 primary melanoma transcriptomes were generated from the Leeds Melanoma Cohort (LMC). The prognostic value of existing signatures across all the AJCC stages was tested. Unsupervised clustering was performed, and the prognostic value of the resultant signature was compared with that of sentinel node biopsy (SNB) and tested as a biomarker in three published immunotherapy datasets. Results: Previous Lund and The Cancer Genome Atlas signatures predicted outcome in the LMC dataset (P = 10−8 to 10−4) but showed a significant interaction with AJCC stage (P = 0.04) and did not predict outcome in stage I tumors (P = 0.3–0.7). Consensus-based classification of the LMC dataset identified six classes that predicted outcome, notably in stage I disease. LMC class was a similar indicator of prognosis when compared with SNB, and it added prognostic value to the genes reported by Gerami and colleagues. One particular LMC class consistently predicted poor outcome in patients receiving immunotherapy in two of three tested datasets. Biological characterization of this class revealed high JUN and AXL expression and evidence of epithelial-to-mesenchymal transition. Conclusions: A transcriptomic signature of primary melanoma was identified with prognostic value, including in stage I melanoma and in patients undergoing immunotherapy

Modeling of Synchronous Data Streams Processing in the RPC Muon Trigger System of the CMS Experiment

This paper presents signal synchronization aspects in a large, distributed, multichannel RPC Muon Trigger system in the CMS experiment. The paper is an introduction to normalized structure analysis methods of such systems. The method introduces a general model of the system, presented in a form of a network of distributed, synchronous, pipeline processes. The model is based on a definition of a synchronous data stream and its formal, fundamental properties. Theoretical considerations are supported by a practical application of synchronous streams and processes management. The following processes were modeled and implemented in hardware: window synchronization, derandomization, data concentration and generation of test pulses. There are presented chosen results of the model application in the CMS experiment

Virtex and Spartan based Lorentz force compensation systems in accelerators

Artykuł opisuje system sterujący czterdziestoma torami kompensującymi w akceleratorze FLASH. System zbudowano w oparciu o układy z rodziny Virtex i Spartan firmy Xilinx. W układach reprogramowalnych zaimplementowano niezbędne algorytmy sterowania. System kompensacji został wykorzystany do wspierania wybranych eksperymentów wysokich energii. Przedstawione wyniki pokazują poprawność przyjętych rozwiązań. Uzyskane rezultaty pozwoliły na obniżenie mocy dostarczanej do akceleratora rzędu 0,5 MW.During pulse operation of a linear accelerator (LINAC), cavities are Lorentz force detuned from its main resonance frequency of 1.3 GHz. The detuned cavities need more radio frequency (RF) control efforts to achieve the desired Free Electron Laser (FEL) parameters. Fast frequency tuners based on piezoelectric elements are commonly used for compensation of cavity detuning. The piezo control system specification and its prototype design are presented in RUC 2008 [2]. The achieved results allow designing a completely new system dedicated for a FLASH accelerator (see Fig. 1). The system digital part was designed with use of FPGA devices of Virtex and Spartan families. The control algorithms were implemented inside FPGA ( Fig. 4). Correction signals generated by the digital system are converted by DAC units and next used to drive piezoelectric actua-tors with dedicated power amplifiers. This paper presents the Lorentz force detuning compensation system used to control forty cavities equipped with fast frequency tuners for the Deutsches Elektronen Synchrotron (DESY) FLASH accelerator. The obtained results show the correctness of the chosen solutions. The applied compensation allow decreasing RF control power of 0.5 MW together with significant increase in the accelerating field gradient (Fig. 6)

Compensation System Based on FPGA Devices and Analog Power Amplifiers for Correction of Superconducting avities' Deformations in Linacs

Podczas pracy impulsowej akceleratora, komory nadprzewodzące ulegają odkształceniom. Do ich kompensacji stosowane są piezoelektryczne elementy wykonawcze sterowane przez wzmacniacze mocy. Jest to część analogowa systemu. Do części cyfrowej zalicza się kontroler oparty o reprogramowalne układy cyfrowe. Wzmacniacze mocy wzmacniają sygnał korekcyjny do poziomu umożliwiającego wysterowanie elementów wykonawczych, zaś kontroler wylicza odpowiedź wnęk na ten sygnał. Wszystkie bloki obliczeniowe zostały zoptymalizowane pod względem zajętości zasobów układu reprogramowalnego. Artykuł przedstawia wyniki testów opisywanego systemu w środowisku akceleratora liniowego FLASH.The Superconducting (SC) cavities are deformed during the pulse operation of the linear accelerators. Power amplifiers together with piezoelectric actuators are used for the compensation purpose as an analog parts of the system. The digital part consists of dedicated control board - Simcon DSP based on FPGA device Virtex II Pro from Xilinx. The power amplifiers - Piezo Drivers are used to amplify the correction signal with the proper voltage levels allowing to drive the actuators. The cavities' response for compensation signal - detuning is calculated by digital controller. The computation blocks were optimized to meet available FPGA resources and latency of 10 ns. The detuning result will be applied for closed feedback operation of the controller. The paper presents the recent development of the system and performed tests in FLASH (Free Electron Laser in Hamburg) accelerator

M10.6.9: Design and fabrication of AMC modules for controlling step motors, piezo and waveguide tuners

FLASH accelerator is using superconducting RF cavities to accelerate electron beam. These cavities must be precisely tuned to RF frequency due to very high Q factor (~109 unloaded Q and ~106 loaded Q). They are tuned by slight dimension change (particularly length) induced by tuners driven by step motors. For high gradients (~20MV/m and more) the cavities are dynamically detuned during RF pulse due to Lorentz Force Detuning (LFD). To keep them in resonance the fast tuners with piezos are used. Both slow and fast tuners need the control integrated with the LLRF system

Spartan 6 based multichannel measurement-control board for piezoelectric actuator control systems

Prezentowany system umożliwia jednoczesną kompensację 16 wnęk rezonansowych zaopatrzonych w podwójne piezoelektryczne elementy wykonawcze. Pracę urządzenia nadzoruje nowoczesny układ reprogramowalny rodziny Spartan 6, umożliwiający nie tylko równoległe przetwarzanie sygnałów cyfrowych, ale także wymianę informacji cyfrowych z wykorzystaniem szybkich interfejsów szeregowych. Artykuł przedstawia pierwsze wyniki testów działania systemu po zainstalowaniu go w hali eksperymentalnej.The system presented in the paper allows simultaneous compensation of 16 resonant cavities equipped with double piezoelectric actuators, as depicted in Fig. 1. The device operation is assured by Spartan 6 FPGA equipped with digital signal processing units and fast serial links. The analog part of the system is based on a matrix of power amplifiers that allows driving the piezo elements with voltages up to š70 V. Since the piezo elements can be also used as mechanical vibration sensors, multichannel ADCs have been applied to provide fast data acquisition. The piezo actuator and sensor functionality can be exchanged remotely using switching relays. The input and output voltage as well as output current of the power amplifiers have been used for monitoring purpose. The piezo control system sends and receives data from the main signal processing unit (?TCA). The usage of fast serial links enables data throughput up to 125 Mb/s. The paper presents the results of the system performance measurements after its installation in a cryomodule test bench (CMTB). During the tests the main functionality of the module has been checked, as shown in Tab. 1. The system has been also used for adaptive compensation of cavity detuning during RF pulse operation with accelerating field gradients up to 18 MV/m (see Fig. 7). The presented solution will be applied in the incoming X-Ray Free Electron Lase

TRIDAQ systems in HEP experiments at LHC accelerator

The paper describes Trigger and Data Acquisition (TRIDAQ) systems of accelerator experiments for High Energy Physics. The background for physics research comprises assumptions of the Standard Model theory with basic extensions. On this basis, a structure of particle detector system is described, with emphasis on the following functional blocks: Front-End Electronics, Trigger and DAQ systems. The described solutions are used in the LHC experiments: ATLAS, ALICE, CMS and LHCb. They are also used in other accelerator experiments. Data storage and processing functionality is divided into two hardware systems: Trigger and Data Acquisition, that are dependent on each other. High input data rate impose relevant choices for the architecture and parameters of both systems. The key parameters include detailed system structure and its overall latency. Trigger structure is defined by the physics requirements and the storage capability of DAQ system. Both systems are designed to achieve the highest possible space and time resolution for particle detection. Trigger references are reviewed [1]–[39] as well as chosen accelerator research efforts originating in this country [40]–[83]