Joint Transmit and Receive Filters Design for Multiple-Input Multiple-Output (MIMO) Systems

Manuscript received April 18, 2003; revised January 19, 2004; accepted April 8, 2004. The editor coordinating the review of this paper and approving it for publication is R. Murch.Multiple transmit (Tx) and multiple receive (Rx) antennas systems, referred to as multiple-input multiple-output (MIMO) systems, have been proposed to achieve higher data rates in wireless communication systems. In this paper, we investigate joint design of transmitter and receiver for the MIMO system when the channel information is available at both transmitter and receiver. We discuss the problem concerning the design of Tx and Rx filters with the aim of minimizing the bit-error probability (BEP).We derive the optimum Tx and Rx filters when the number of data symbols is two. For a general number of data symbols, we derive a Tx and Rx filters design criterion referred to as equal signal-to-noise plus interference ratio (SNIR) criterion, and propose Tx and Rx filters based on this equal SNIR criterion. The performance of the proposed filter is compared with that of the conventional minimum mean-squared error (MMSE) filter. Performance analysis shows that the proposed filter provides a significant improvement over the MMSE filter in BEP and spectral efficiency

Efficient Weight Vector Representation for Closed-Loop Transmit Diversity

For a closed-loop transmit (Tx) diversity, the Tx weights are calculated at a receiver, and fed back to a transmitter. As the number of Tx antennas increases, the potential gain of closed-loop Tx diversity may be significant. However, the amount of feedback information, which is the number of Tx weights that should be fed back, linearly increases, and the performance improvement of a closed-loop Tx diversity system may not be as significant as expected due to delay in the feedback process. Thus, an efficient Tx weight representation, which can reduce the amount of feedback information, is needed. In this letter, a Tx weight vector representation is presented, and its performance is analyzed. Analysis shows that this weight vector representation, referred to as basis selection, significantly reduces the amount of feedback information with little performance degradation

Percutaneous Endoscopic Lumbar Foraminoplasty for Resection of Synovial Cyst

Synovial cyst is an extradural mass that compresses nerve root or thecal sac. Surgical excision with partial hemilaminectomy and medial facetectomy is commonly used for synovial cyst. Remarkable advancements in endoscopic spinal surgery have led to successful outcomes comparable to conventional open surgery. Here we introduce percutaneous endoscopic lumbar foraminoplasty for resecting synovial cyst as a minimal invasive technique. A 59-year-old woman presented with radicular pain at left L5 dermatome. Magnetic resonance images demonstrated a synovial cyst at left L4-5 facet joint and degenerative spondylolisthesis on L4-5. Under endoscopy, synovial cyst was removed by piecemeal method after transforaminal endoscopic foraminoplasty that removed part of superior facet. Her symptoms were relieved and the patient was discharged the next day. Therefore, percutaneous endoscopic lumbar foraminoplasty can be used as a minimally invasive surgical option for synovial cyst. It may provide less traumatization and affect less postoperative instability

Origin of Difference in the Reactivity of Aliphatic and Aromatic Guanidine-containing Pharmaceuticals Toward [18F]Fluorination: Coulombic Forces and Hydrogen Bonding

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151351/1/bkcs11842.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151351/2/bkcs11842_am.pd

KITENIN increases invasion and migration of mouse squamous cancer cells and promotes pulmonary metastasis in a mouse squamous tumor model

AbstractKAI1 C-terminal interacting tetraspanin (KITENIN) is reported to promote metastasis in mouse colon cancer models. We investigated the role of KITENIN on the progression of squamous cell carcinoma (SCC). In a preliminary clinical study using resected tissues from head and neck SCC patients, KITENIN was highly expressed in tumors and metastatic lymph nodes, while KAI1 was more increased in adjacent mucosa than in tumor. KITENIN-transfected mouse squamous cancer (SCC VII/KITENIN) cells showed significantly higher invasion, migration, and proliferation than empty vector-transfected cells. In syngeneic mouse squamous tumor models, more increased tumor volume and enhanced lung metastasis were found in SCC VII/KITENIN cells-injected mice. Thus, KITENIN increases invasion and migration of squamous cancer cells and thereby promotes distant metastasis in mouse squamous tumor models

Patients with systemic lupus erythematosus have abnormally elevated Epstein–Barr virus load in blood

Various genetic and environmental factors appear to be involved in systemic lupus erythematosus (SLE). Epstein–Barr virus (EBV) is among the environmental factors that are suspected of predisposing to SLE, based on the characteristics of EBV itself and on sequence homologies between autoantigens and EBV antigens. In addition, higher titers of anti-EBV antibodies and increased EBV seroconversion rates have been observed in SLE patients as compared with healthy control individuals. Serologic responses do not directly reflect EBV status within the body. Clarification of the precise status of EBV infection in SLE patients would help to improve our understanding of the role played by EBV in this disease. In the present study we determined EBV types in SLE patients (n = 66) and normal control individual (n = 63) by direct PCR analysis of mouthwash samples. We also compared EBV load in blood between SLE patients (n = 24) and healthy control individuals (n = 29) using semiquantitative PCR assay. The number of infections and EBV type distribution were similar between adult SLE patients and healthy control individuals (98.5% versus 94%). Interestingly, the EBV burden in peripheral blood mononuclear cells (PBMCs) was over 15-fold greater in SLE patients than in healthy control individuals (mean ± standard deviation: 463 ± 570 EBV genome copies/3 μg PBMC DNA versus 30 ± 29 EBV genome copies/3 μg PBMC DNA; P = 0.001), suggesting that EBV infection is abnormally regulated in SLE. The abnormally increased proportion of EBV-infected B cells in the SLE patients may contribute to enhanced autoantibody production in this disease

Functional MR Imaging of Psychogenic Amnesia: A Case Report

We present here a case in which functional MR imaging (fMRI) was done for a patient who developed retrograde psychogenic amnesia for a four year period of her life history after a severe stressful event. We performed the fMRI study for a face recognition task using stimulation with three kinds of face photographs: recognizable familiar faces, unrecognizable friends' faces due to the psychogenic amnesia, and unfamiliar control faces. Different activation patterns between the recognizable faces and unrecognizable faces were found in the limbic area, and especially in the amygdala and hippocampus

Fiber Type Specific Presence of GIutathione Transferase Isoenzymes in the Rat SkeIetaI Musele Tissue

Glutathione transferases (GST) are a group of enzymes, majorly responsible for biochemical detoxification by conjugating glutathione to a set of hydrophobic ligands. The tissue isoenzyme pattern of the enzymes has been well illustrated with their significance of histological localization. But in the cases of muscle tissue, the GST isoenzyme pattern has not yet been clearly studied. In the present experiment, we have carried out an immunohistochemical analysis on the distribution of GST isoenzymes using anti GST-P and anti GST-L antibodies on cardiac, smooth and skeletal muscle tissues. The results showed that the intestinal smooth muscle and cardiac muscles are very weakly immunostained for both anti GST-L and P antibodies. In contrast, major bundles of skeletal muscles were positively responsive to GST-L antibody. Therefore, we compared the expression of GST-L in the muscle tissues of the soleus and plantaris, which were composed dominantly of type I fiber and type II fiber, respectively. The data indicated that only type II fibers in the plantaris muscle tissue were positive to GST-L antibody, which was confirmed by specific ATPase staining. And the soleus muscle, consisting mainly of type I fibers, contains a higher amount of GST-P isoenzyme than the plantaris muscle. Therefore, it can be suggested that the expression of GST isoenzyme can be used as a type-specific marker for the type II fiber of skeletal muscles. And moreover, the differential pattern of GST isoenzymes in those muscle tissues according to fiber types may contribute to explaining the differences in fatigue-sensitivity of muscles to exercise