Augmented Weighted Estimators Dealing with Practical Positivity Violation to Causal inferences in a Random Coefficient Model.

The inverse probability of treatment weighted (IPTW) estimator can be used to make causal inferences under two assumptions: (1) no unobserved confounders (ignorability) and (2) positive probability of treatment and of control at every level of the confounders (positivity), but is vulnerable to bias if by chance, the proportion of the sample assigned to treatment, or proportion of control, is zero at certain levels of the confounders. We propose to deal with this sampling zero problem, also known as practical violation of the positivity assumption, in a setting where the observed confounder is cluster identity, i.e., treatment assignment is ignorable within clusters. Specifically, based on a random coefficient model assumed for the potential outcome, we augment the IPTW estimating function with the estimated potential outcomes of treatment (or of control) for clusters that have no observation of treatment (or control). If the cluster-specific potential outcomes are estimated correctly, the augmented estimating function can be shown to converge in expectation to zero and therefore yield consistent causal estimates. The proposed method can be implemented in the existing software, and it performs well in simulated data as well as with real-world data from a teacher preparation evaluation study

Effects of Choline Chloride, Urea and Their Deep Eutectic Solvents on the Modification of Leather

Content: The application of split leather is an important issue in leather industry as most of them was not properly treated and wasted. In this study the application of choline chloride (ChCl), urea (U) and corresponding deep eutectic solvents (DES) on the modification of thermal stability and mechanical strength of mink split leather was investigated. TGA and DSC results indicated DES treatment enhanced thermal stability of split leather, and ChCl treatment reduced the stability. While, U treatment provided a kinetic inhibition during the thermal-decomposition. In terms of the mechanical strength, both ChCl and U treatment reduced burst intensity and extended height. While, after DES treatment the burst intensity and extended height increased significantly. In terms of the dosage, 7% DES provided best performance. Results mentioned above illustrated that DES formed by simply mixing ChCl and U provided strong interaction with fiber, enhanced the crosslinks. A hypothesis of [Ch(Urea)]+[Cl(Urea)]- type structure was proposed, as it enabled DES forming strong hydrogen bonds with functional groups on leather fiber, enhancing the crosslinks and therefore improving the thermal stability and mechanical strength. The DES treatment on leather fibers improved their overall performance and thereby broaden their applications. Take-Away: 1. DES obtained by mixing ChCl and urea presented very different effect in leather treatment, as the thermal stability and physical strength of leather improved significantly after the DES treatment. 2. A hypothesis of [Ch(Urea)]+[Cl(Urea)]- type structure was proposed, illustrating a formation of strong hydrogen bonds between DES and functional groups on leather fiber. This enhances the crosslinks and therefore improves the thermal and mechanical strength of leather

The impact of a vaginal brachytherapy boost to pelvic radiation in stage III endometrial cancer.

PURPOSE:We investigate the use and impact of a vaginal brachytherapy boost (VBB) after pelvic radiotherapy for stage III endometrial adenocarcinoma on vaginal and pelvic control. MATERIAL AND METHODS:One hundred patients treated from 1998-2011 with surgery and adjuvant therapy with or without a VBB were included. Variables examined were grade, stage, lymphovascular space invasion (LVSI), vaginal involvement (VI), cervical stromal involvement (CSI), myometrial invasion (MI), and a VBB. Failure was scored as vaginal, or pelvic. Fisher's exact test assessed association between variables with vaginal and pelvic control. RESULTS:With a median follow up of 43 months, 31% were stage IIIA, 6% stage IIIB, and 63% stage IIIC. Thirty-eight (38%) received pelvic radiotherapy alone, and 62% received adjuvant chemotherapy. Of the 100 patients, 82 were treated with a VBB, 10 were not treated with a VBB, and 8 were not treated with RT. Of the 82 patients who received a VBB, 5 failed in the vagina with vaginal and pelvic control rates of 94% and 92%. The impact of VB reached borderline significance with its impact on pelvic control, 92% vs. 70% (p = 0.056), and did not affect vaginal control, 94% and 90% (p = 0.50). Neither tumor grade, LVSI, CSI, stage, nor LVSI (p > 0.05) statistically significantly impacted vaginal control. CONCLUSIONS:There are no clinical guidelines for the use of a VBB in stage III endometrial cancer. The majority of our patients were treated with a VBB and experienced excellent pelvic and vaginal control. The presence of traditional adverse features did not negatively impact control in our patient cohort. However, the role of a VBB needs further investigation to understand the incremental benefit beyond pelvic RT

ShiBASE: an integrated database for comparative genomics of Shigella

Among the major enteric bacterial pathogens, Shigella is found to display extreme genome diversity and dynamics, which imposes a challenge in comparative genomic studies. To facilitate further studies in this area, we have constructed an integrated online database, ShiBASE (),which contains Shigella genomic sequences of four species and additional comparative genomic hybridization (CGH) data of 43 serotypes. ShiBASE offers online comparative analysis on DNA sequences, gene orders, metabolic pathways and virulence factors. In addition, ShiBASE has a newly developed online comparative visualization service, Shi-align, which enables the alignment of any query sequence with the reference genome sequences

Oxidative Degradation of Fentanyl in Aqueous Solutions of Peroxides and Hypochlorites

Fentanyl widely used in clinics as practices is potentially utilised as an incapacitant in countering terrorism and its analogues would be used as an addictive drug, so the degradation of these compounds need to be investigated for protecting environment and human health. In this work, the degradation of fentanyl was examined in a series of oxidant aqueous solutions. Meanwhile, the degradation pathways of fentanyl in the oxidant solution were discussed according to all products identified by GC/MS and LC/MS.Defence Science Journal, 2011, 61(1), pp.30-35, DOI:http://dx.doi.org/10.14429/dsj.61.6

Single-shot compressed ultrafast photography: a review

Compressed ultrafast photography (CUP) is a burgeoning single-shot computational imaging technique that provides an imaging speed as high as 10 trillion frames per second and a sequence depth of up to a few hundred frames. This technique synergizes compressed sensing and the streak camera technique to capture nonrepeatable ultrafast transient events with a single shot. With recent unprecedented technical developments and extensions of this methodology, it has been widely used in ultrafast optical imaging and metrology, ultrafast electron diffraction and microscopy, and information security protection. We review the basic principles of CUP, its recent advances in data acquisition and image reconstruction, its fusions with other modalities, and its unique applications in multiple research fields