BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

A Laue microdiffraction beamline(BL03HB) was constructed at the Shanghai Synchrotron Radiation Facility(SSRF).This beamline features two consecutive focusing points in two different sectors within its end station, the first dedicated to protein crystallography and the other tailored to materials science applications. Based on a superbend dipole magnet with a magnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick-Baez mirrors to achieve a micro white beam as small as 4.2 μ m ×4.3 μ m at the first sector and 0.9 μ m ×1.3 μ m at the second sector in the standard beamline operation mode at SSRF. The X-ray microbeam in the two sectors can be easily switched between monochromatic and white beams by moving a four-bounce monochromator in or out of the light path, respectively. In the protein crystallography sector, white-beam Laue microdiffraction was demonstrated to successfully determine the structure of protein crystals from only a few images of diffraction data collected by a Pilatus 2 M area detector. In the materials science sector,the white-beam Laue diffraction was collected in a reflection geometry using another Pilatus 2 M area detector, which could map the microstructural distribution on the sample surface by scanning the samples. In general, the BL03HB beamline promotes the application of Laue microdiffraction in both protein crystallography and materials science. This paper presents a comprehensive overview of the BL03HB beamline, end station, and the first commission results.

The protein complex crystallography beamline(BL19U1)at the Shanghai Synchrotron Radiation Facility

The protein complex crystallographic beamline BL19U1 at the Shanghai Synchrotron Radiation Facility is one of the five beamlines dedicated to protein sciences operated by National Facility for Protein Science(Shanghai,China).The beamline,which features a small-gap invacuum undulator,has been officially open to users since March 2015.This beamline delivers X-ray in the energy range 7–15 keV.With its high flux,low divergence beam and a large active area detector,BL19U1 is designed for proteins with large molecular weight and large crystallographic unit cell dimensions.Good performance and stable operation of the beamline have allowed the number of Protein Data Bank(PDB)depositions and the number of articles published based on data collected at this beamline to increase steadily.To date,over 300 research groups have collected data at the beamline.More than 600 PDB entries have been deposited at the PDB(www.pdb.org).More than 300 papers have been published that include data collected at the beamline,including 21 research articles published in the top-level journals Cell,Nature,and Science.

Female-specific vs conventional knee prostheses after total knee arthroplasty:A meta-analysis

AIM： To study whether female-specifc prostheses are superior to conventional prostheses after total knee arthroplasty （TKA） by conducting this meta-analysis to evaluate the effects of the 2 different designs.METHODS： A systematic electronic search was con-ducted in the databases of PubMed, EMBASE and the Cochrane Library for prospective and retrospective trials. Meta-analysis was performed for the outcomes, includ-ing range of motion （ROM）, Knee Society score, Hospi-tal for Special Surgery scores （HSS） and complications including deep infection, manipulation under anesthesia （MUA）, revisions, anterior knee pain, deep vein throm-bosis and overhang rate. Meta-analysis was conductedwhere applicable. Weighted mean difference （WMD） and odds ratio were calculated according to study type.RESULTS： Seven studies including 1174 knees wereeligible for data extraction and pooled analysis. The overhang rate of female-specifc prostheses was signif-cantly lower than the conventional ones （WMD, 3.25; 95%CI： 0.00-0.27; P = 0.001）. ROM in the female-spe-cifc prostheses group after TKA tended to be greater than the conventional prostheses group; however, with insignifcant difference （WMD, 2.48; 95%CI： -0.83-5.78; P = 0.14）. HSS （WMD, 0.48; 95%CI： -1.45-0.88; P = 0.63） and complications including deep infection （WMD, 0.39; 95%CI： 0.19-3.08; P =0 .70）, MUA （WMD, 1.53; 95%CI： 0.02-1.61; P = 0.13） and revisions （WMD, 0.55; 95%CI： 0.07-4.34; P = 0.13） were all comparable be-tween the two groups with at least 1 year follow-up. Other indexes were revealed to be similar between the two treatments with a descriptive analytical method.CONCLUSION： Although the overhang rate is lower with female-specific prostheses, the current evidence does not support that female-specific prostheses out-weigh conventional ones after TKA.