Model Selection in High-Dimensional Block-Sparse Linear Regression

Model selection is an indispensable part of data analysis dealing very frequently with fitting and prediction purposes. In this paper, we tackle the problem of model selection in a general linear regression where the parameter matrix possesses a block-sparse structure, i.e., the non-zero entries occur in clusters or blocks and the number of such non-zero blocks is very small compared to the parameter dimension. Furthermore, a high-dimensional setting is considered where the parameter dimension is quite large compared to the number of available measurements. To perform model selection in this setting, we present an information criterion that is a generalization of the Extended Bayesian Information Criterion-Robust (EBIC-R) and it takes into account both the block structure and the high-dimensionality scenario. The analytical steps for deriving the EBIC-R for this setting are provided. Simulation results show that the proposed method performs considerably better than the existing state-of-the-art methods and achieves empirical consistency at large sample sizes and/or at high-SNR.Comment: 5 pages, 2 figure

Family-led rehabilitation after stroke in India (ATTEND): a randomised controlled trial

Background: Most people with stroke in India have no access to organised rehabilitation services. The effectiveness of training family members to provide stroke rehabilitation is uncertain. Our primary objective was to determine whether family-led stroke rehabilitation, initiated in hospital and continued at home, would be superior to usual care in a low-resource setting. Methods: The Family-led Rehabilitation after Stroke in India (ATTEND) trial was a prospectively randomised open trial with blinded endpoint done across 14 hospitals in India. Patients aged 18 years or older who had had a stroke within the past month, had residual disability and reasonable expectation of survival, and who had an informal family-nominated caregiver were randomly assigned to intervention or usual care by site coordinators using a secure web-based system with minimisation by site and stroke severity. The family members of participants in the intervention group received additional structured rehabilitation training—including information provision, joint goal setting, carer training, and task-specific training—that was started in hospital and continued at home for up to 2 months. The primary outcome was death or dependency at 6 months, defined by scores 3–6 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) as assessed by masked observers. Analyses were by intention to treat. This trial is registered with Clinical Trials Registry-India (CTRI/2013/04/003557), Australian New Zealand Clinical Trials Registry (ACTRN12613000078752), and Universal Trial Number (U1111-1138-6707). Findings: Between Jan 13, 2014, and Feb 12, 2016, 1250 patients were randomly assigned to intervention (n=623) or control (n=627) groups. 33 patients were lost to follow-up (14 intervention, 19 control) and five patients withdrew (two intervention, three control). At 6 months, 285 (47%) of 607 patients in the intervention group and 287 (47%) of 605 controls were dead or dependent (odds ratio 0·98, 95% CI 0·78–1·23, p=0·87). 72 (12%) patients in the intervention group and 86 (14%) in the control group died (p=0·27), and we observed no difference in rehospitalisation (89 [14%]patients in the intervention group vs 82 [13%] in the control group; p=0·56). We also found no difference in total non-fatal events (112 events in 82 [13%] intervention patients vs 110 events in 79 [13%] control patients; p=0·80). Interpretation: Although task shifting is an attractive solution for health-care sustainability, our results do not support investment in new stroke rehabilitation services that shift tasks to family caregivers, unless new evidence emerges. A future avenue of research should be to investigate the effects of task shifting to health-care assistants or team-based community care. Funding: The National Health and Medical Research Council of Australia

Dimethyl 2,6-dimethyl-4-phenyl­pyridine-3,5-dicarboxyl­ate

In the title compound, C17H17NO4, the dihedral angle between the benzene and pyridine rings is 75.51 (4)°. The benzene and pyridine rings are both approximately planar (r.m.s. deviations of 0.0040 and 0.0083 Å, respectively), indicating that the pyridine N atom is not protonated. The crystal structure is stabilized by weak inter­molecular C—H⋯O and C—H⋯N inter­actions

5-(3,4-Dimeth­oxy­benzyl­idene)-1,3-dimethyl-1,3-diazinane-2,4,6-trione

In the title compound, C15H16N2O5, the dihedral angle between 1,3-diazinane and benzene rings is only 4.27 (1)°. The essentially planar mol­ecular structure is characterized by a short intra­molecular C—H⋯O separation and by an exceptionally large bond angle of 138.25 (14)° at the bridging methine C atom. The meth­oxy groups deviate somewhat from the plane of the benzene ring, with C—C—O—C torsion angles of −15.6 (1) and 9.17 (6)°. In the crystal, mol­ecules form centrosymmetric dimers via donor–acceptor π–π inter­actions, with a centroid–centroid distance of 3.401 (1) Å

Racemic tricarbon­yl[7-meth­oxy-2-(η6-phen­yl)chromane]­chromium(0)

In the title compound, [Cr(C16H16O2)(CO)3], the Cr0 atom of the Cr(CO)3 unit is coordinated to the phenyl ring of the flavan ligand in an η6 mode, with a normal arene-to-metal distance. The Cr(CO)3 unit exhibits a three-legged piano-stool conformation, while the dihydro­pyran ring displays a distorted envelope configuration. The phenyl ring is twisted away from the fused ring system by 25.5 (2)°. The meth­oxy group is almost coplanar with the phenyl ring [CMe—O—Car—Car torsion angle = 8.46 (2)°]. The crystal packing is stabilized by inter­molecular C—H⋯O inter­actions

Cloning and heterologous expression of a gene encoding lycopene-epsilon-cyclase, a precursor of lutein in tea (Camellia sinensis var assamica)

This report describes the cloning and expression of a gene lycopene epsilon cyclase, (LCYE) from Camellia sinensis var assamica which is a precursor of the carotenoid lutein in tea. The 1982 bp cDNA sequence with 1599 bp open reading frame of LCYE was identified from an SSH library constructed for quality trait in tea. 5’ and 3’ RACE (rapid-amplification of cDNA ends) was done to clone the full length cDNA of LCYE. Homology studies showed that the deduced amino acid sequence of LCYE gene had the highest sequence identity of up to 84% with Vitis vinefera. The cloned gene was successfully expressed in a PET based Escherichia coli expression system. The size of the expressed protein was 59615 Daltons. A suppression subtractive library was constructed using a quality clone H3111 (tester) and a garden series clone T3E3 (driver).Key words: Carotenoid, RACE, heterologous expression, lutein, tea