A New SLNR-based Linear Precoding for Downlink Multi-User Multi-Stream MIMO Systems

Signal-to-leakage-and-noise ratio (SLNR) is a promising criterion for linear precoder design in multi-user (MU) multiple-input multiple-output (MIMO) systems. It decouples the precoder design problem and makes closed-form solution available. In this letter, we present a new linear precoding scheme by slightly relaxing the SLNR maximization for MU-MIMO systems with multiple data streams per user. The precoding matrices are obtained by a general form of simultaneous diagonalization of two Hermitian matrices. The new scheme reduces the gap between the per-stream effective channel gains, an inherent limitation in the original SLNR precoding scheme. Simulation results demonstrate that the proposed precoding achieves considerable gains in error performance over the original one for multi-stream transmission while maintaining almost the same achievable sum-rate.Comment: 8 pages, 1 figur

Community Participation in Mine Action: A Review and Conceptual Framework

In line with the Norwegian People\u27s Aid (NPA) international strategy, which promotes a rights-based partnership approach, the NPA is committed to exploring new approaches to mine action that promote greater involvement of the local mine affected populations. A starting point in this process is a review and conceptual framework paper prepared for NPA by Ruth Bottomley. Through a review of existing documents, the paper provides a reflection on why community participation is important in mine action and outlines some of the challenges. Existing examples of community participation in mine action are compiled with documented strengths and weaknesses

4α,6α-Dihy­droxy-1β-methyl­sulfonyl-8α,9α-ep­oxy-2β,12-epoxymethano-β-dihydro­agarofuran

The title mol­ecule, C16H24O8S, is a dihydro­agrofuran derivative and has a heteropolycyclic structure. One cyclohexane ring exhibits a chair conformation and the other a non-chair conformation. In the crystal structure there is an inter­molecular C—H⋯O hydrogen-bonding inter­action to stabilize the packing

CREB1 and ATF1 Negatively Regulate Glutathione Biosynthesis Sensitizing Cells to Oxidative Stress

The cAMP response element binding protein (CREB) family activating transcription factor 1 (ATF1) and cAMP response element binding protein 1 (CREB1) have been reported in a diverse group of tumors, however, the mechanistic basis for this remains unclear. Here we found that CREB1 and ATF1 unexpectedly regulate glutathione (GSH) biosynthesis by suppressing the expression of glutamate-cysteine ligase modifier subunit (GCLM) and glutathione synthase (GSS), two key enzymes of GSH biosynthesis pathway. Mechanistic studies reveal that GCLM and GSS are direct transcriptional targets of CREB1 and ATF1. Through repressing the expression of these two enzymes, CREB1 and ATF1 reduce the GSH biosynthesis and the capability of cells to detoxicate reactive oxygen species (ROS), thereby increasing cellular susceptibility to oxidative stress. Therefore, our findings link CREB1 family to cellular metabolism, and uncover a potential therapeutic approach by targeting GCLM or oxidative stress for the treatment of tumors with relatively high expression of CREB1 family proteins