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The External Target Facility (ETF) has been constructed for reaction studies with high-energy secondary beams of several hundred MeV/u. The charged fragment detector system of ETF consists of a dipole magnet, tracking drift chambers, ionization chambers and plastic scintillators for particle identification (PID) via B ρ - Δ E-TOF method. The system is now ready for physics experiments. Before physics runs, it has been tested using 280 MeV/u 18O primary beam as well as the secondary beams produced by projectile fragmentation. The system used as a magnetic spectrometer has exhibited satisfying PID capability in identifying fragments ranging from nitrogen to beryllium.

A Time-Of-Flight Wall (TOFW) detector has been designed and constructed at the External Target Facility (ETF) of HIRFL-CSR. The detector covers a sensitive area of 1.2 × 1.2 m 2 and consists of 30 modules. Each module is composed of a long plastic scintillator bar with two photo-multiplier tubes coupled at both ends for readout. The design and manufacture details are described and the test results are reported. The performance of the TOFW detector has been tested and measured with cosmic rays and a 310 MeV/u 40Ar beam. The results show that the time resolutions of all the TOFW modules are better than 128 ps, satisfying the requirements of the experiments which will be carried out at the ETF.

A drift chamber array at the External Target Facility in HIRFL-CSR has been constructed for three-dimensional particle tracking in high-energy radioactive ion beam experiments. The design, readout, track reconstruction program and calibration procedures for the detector are described. The drift chamber array was tested in a 311 AMeV 40Ar beam experiment. The detector performance based on the measurements of the beam test is presented. A spatial resolution of 230 μ m is achieved.

There have been extensive experimental observations of the anisotropic corrosion behavior of metals and alloys, and their mechanisms were assumed to be correlated with the so-called surface energy or the work function. However, to date, a specified mechanism or theory to interpret anisotropic corrosion behavior remains unclear. Here, we determine the anisotropic anodic dissolution of metals and alloys in corrosive environments by developing a formula to specify the relationship between the electrode potential (U) and the current density (I) by considering the basic parameters of our defined surface energy density ( E s u r f / ρ ) and the work function ( Φ ). Therefore, we build an ab initio model to evaluate the anisotropic anodic dissolution behavior of metals and alloys using the inputs obtained within density functional theory. This theory is further validated in the case of variations in the crystallographic planes of Mg. Moreover, some selected alloying additions such as Ga, Cd, Hg, In, As, and Cr are theoretically elucidated to effectively reduce the anodic dissolution rates of the Mg matrix to some extent, in close agreement with available experimental observations. This model is capable of predicting the anisotropic anodic dissolution behavior, providing a promising perspective for designing better corrosion-resistant alloys.

The China Spallation Neutron Source (CSNS) is a high intensity proton accelerator-based facility, and its accelerator complex includes two main parts: a H- linac and a rapid cycling synchrotron (RCS). The RCS accumulates the 80 MeV proton beam, and accelerates it to 1.6 GeV, with a repetition rate of 25 Hz. The beam commissioning of RCS began in May, 2017 and reached the target beam power of 100 kW in February, 2020. The longitudinal beam dynamics study plays the key role in the commissioning. The study and optimization include the synchronicity between the ramping magnet field and the RF system, the mitigation of the high intensity effects to minimize the beam loss and the measurement of the longitudinal dynamics. Through the optimization of the bunch factor, the strong space charge effects with high intensity is mitigated, thus the RCS transmission efficiency arrives mostly at 100 %. The beam distribution is not affected by the phase loop with a new algorithm and the beam loss is smaller than the original one. The beam commissioning in longitudinal plane is reviewed in the paper.

An improved tracking method was devised for tracking in large-acceptance spectrometers in intermediate-energy RIB experiments, where drift chamber arrays are deployed both upstream and downstream of a dipole magnet for particle tracking outside the magnetic field. By incorporating into the tracking χ 2 the inconsistencies between the tracks entering and exiting the reaction target, and that between the tracks entering and exiting the dipole magnet, the improved tracking method has proved to be effective in eliminating spurious tracks in data analysis of RIB experiments. With the tracking method, enhanced particle identification and reaction cross sections are achieved for neutron-removal products of secondary carbon-isotope beams at around 240 MeV/u in the External Target Facility in HIRFL-CSR.

A multiple sampling ionization chamber used as a particle identification device for high energy heavy ions has been developed for the External Target Facility. The performance of this detector was tested with a 239Pu α source and RI beams. A Z resolution (FWHM) of 0.4–0.6 was achieved for nuclear fragments of 18O at 400 AMeV.

This report describes the analytical validation and application of the homogeneous mobility shift assay (HMSA) method for the measurement of adalimumab and human antibodies-to-adalimumab (ATA) in serum samples from patients who have lost response to adalimumab treatment. Validation of the ATA- and the adalimumab-HMSA revealed a lower limit of detection to be 0.026U/mL for ATA and 0.018μg/mL for adalimumab in serum samples. Intra-assay and inter-assay precision determination yielded a coefficient of variation of less than 15%, and the accuracy of both assays was within 20%. Adalimumab drug tolerance in the ATA-HMSA was up to 20μg/mL in the test serum. Serum samples from 100 drug-naïve healthy subjects were tested to set-up the cut point of 0.55U/mL for ATA and 0.68μg/mL for adalimumab. Analysis of 100 serum samples from patients who were losing response to adalimumab showed that 26% had an adalimumab level below the cut point, of these 68% were ATA positive. Overall, 44% of the patients (44/100) were positive for ATA. This study presents evidence that drug and anti-drug antibody levels are important determinants of patient response to therapy.

Antibody-based drugs such as infliximab (IFX) are effective for the treatment of inflammatory bowel disease (IBD) and other immune-mediated disorders. The development of antibodies against these drugs may result in unfavorable consequences, including the loss of drug efficacy, hypersensitivity reactions, and other adverse events. Therefore, accurate monitoring of serum drug and anti-drug antibody levels should be an important part of therapy for patients being treated with an antibody-based drug. Current methods for the assessment of anti-drug antibodies and drug levels, involving various bridging ELISA and radioimmunoassay techniques, are limited by their sensitivity, interference, and/or complexity. To overcome these limitations, we have developed a non-radiolabeled homogeneous mobility shift assay (HMSA) to measure the antibodies-to-infliximab (ATI) and IFX levels in serum samples. Full method validation was performed on both the ATI- and IFX-HMSA, and the clinical sample test results were also compared with those obtained from a bridging ELISA method to evaluate the difference in performance between the two assays. Validation of the ATI-HMSA revealed a lower limit of quantitation of 0.012μg/mL in serum. The linear range of quantitation was 0.029–0.54μg/mL. The intra- and inter-assay precision was less than 20% of coefficient of variation (CV), and the accuracy (% error) of the assay was less than 20%. In serum samples, ATI as low as 0.036μg/mL can be measured, even in the presence of 60μg/mL of IFX in the serum. Sera from 100 healthy subjects were tested to determine the cut point of the assay. ATI-positive samples that had been previously analyzed by using a bridging ELISA from 100 patients were also measured by the new method. There was a high correlation between the two methods for ATI levels (p

Sterile, apyrogenic [123I]IBZM was prepared in a sealed, capped ‘V’ vial, followed by SEP-PAK C-18 cartridge purification, and then was placed under sealed vial condensation. The quantity of BZM present in the final product ranged from 3.3–5.9 μg, as measured by a UV spectrophotometer at 254 and 308 nm. Animal biodistribution studies revealed that the [123I]IBZM prepared by this method which contained 5.9 μg of BZM, compared to the standard preparation method containing 0 μg of BZM, resulted in identical brain uptakes at 15, 30, 60, and 120 min post-injection. The in vitro and in vivo studies demonstrated that a small amount of BZM presence in the final product did not affect the radiochemical purity, nor the D2 receptor binding capacity in the rat brain of [123I]IBZM. The preparation time can be shortened to 1.5 h compared with at least 2–4 h needed for the standard method of preparation. This factor may be important in routine clinical application.

The paper entitled ''An extreme case of the generalized optimal discriminant transformation and its application to face recognition'' [X.J. Wu, J.P. Lu, J.Y. Yang, S.T. Wang, J. Kittler, An extreme case of the generalized optimal discriminant transformation and its application to face recognition, Neurocomputing 70(4-6) (2007) 828-834] contains several flaws. The main one is corrected in this note.

The Argonne National Laboratory has designed, constructed and tested a large aperture superconducting MHD magnet for use in the coal-fired flow facility at Tullahoma, Tennessee. The magnet generates a peak on-axis field of 6 T in a MHD warm bore of 80 cm diameter at inlet, 100 cm diameter at outlet, and 300 cm effective length. The stored energy of the magnet is 210 MJ, the cold mass (4.2 K) is 131 metric tons and the ampere-turns, 13.7 × 10 6 . The final design of the magnet will be briefly introduced. Described in detail are the experiences of coil winding and coil assembly, the assembly of force-containment superstructure, assembly of magnet cryostat and results of magnet performance tests.

The biodistribution of radiolabeled mouse anti-pan T monoclonal antibody (W3/13) against rat lymphocytes was examined in normal rats. Monoclonal antibody to human prostate-associated antigens (PAA) served as a control. In vitro studies demonstrated a 38% maximum binding of radiolabeled W3/13 to lymphocytes, which was significant (P less than 0.001) when compared with the control (PAA) value of 3.4%. In vivo, intravenously administered 111In labeled W3/13 and 131I labeled W3/13 exhibited similar tissue distribution patterns. The localization of W3/13 in lymphoid tissue was significantly greater than that achieved with PAA. W3/13, however, did not demonstrate significant localization in the intact thymus and accumulated to a higher degree (6-10% ID/g) than expected in bone marrow at 24 h. These findings suggest that radiolabeled anti-lymphocyte monoclonal antibodies may not be well suited for the treatment of lymphoreticular neoplasms and allograft rejection in patients.

The bicyclic anhydride of DTPA-1- 14 C (BADTPA-1- 14 C) was synthesized and reacted with an antibody to human melanoma associated antigen (MAA) and with one to human class II major histocompatibility complex antigen (HLA-DR). DTPA-1-C incorporation per mole of anti MAA at molar ratios of 1:1 to 200:1 ranged from 0.5 to 25, while immunoreactivity ranged from 49 to 9%. With antibody to HLA-DR, results were similar. Anti MAA, but not anti HLA-DR, demonstrated polymerization upon conjugation. BADTPA-1- 14 C provides a convenient and accurate method for measuring the amount of DTPA in monclonal antibody preparations and its effect on immunoreactivity.