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It is widely accepted that single carrier frequency division multiple access (SC-FDMA) is an excellent candidate for broadband wireless systems. Channel estimation is one of the key challenges in SC-FDMA, since accurate channel estimation can significantly improve equalization at the receiver and, consequently, enhance the communication performances. In this paper, we study the application of compressive sensing for sparse channel estimation in a SC-FDMA system. By skillfully designing pilots, their patterns, and taking advantages of the sparsity of the channel impulse response, the proposed system realizes channel estimation at a low cost. Simulation results show that it can achieve significantly improved performance in a frequency selective fading sparse channel with fewer pilots. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma is the third leading cause of cancer-related death in the world, and cirrhosis is the main cause of hepatocellular carcinoma and adversely affects surgical outcomes. Liver resection, liver transplantation, and local ablation are potentially curative therapies for early hepatocellular carcinoma (HCC). There exists an obvious histological variability of severity within cirrhosis which has different clinical stages. For patients with Child-Pugh B cirrhosis and/or portal hypertension and HCC within Milan criteria, consensus guidelines suggest that liver transplantation is the best treatment of choice; liver resection is widely accepted as first-line treatment for patients with early-stage HCC and preserved liver function; and local ablation is the treatment of choice in patients with small tumors who are not candidates for surgery or can be used as a temporary treatment during the waiting period for transplantation. For patients with compensated cirrhosis or Child A cirrhosis, the selection of surgical modality based on subclassification of cirrhosis remains unclear. This review examines the current status of the selection of surgical modality for hepatocellular carcinoma treatment in cirrhotic patients and aims to emphasize the effects of the severity of cirrhosis on the selection of surgical modality for the treatment of hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Purpose: In the east countries, patients with hepatocellular carcinoma (HCC) are usually associated with varied degrees of liver cirrhosis, and anatomic resection is therefore limited to use, especially in those with severe liver cirrhosis. This study aims to evaluate the clinical value of non-anatomic resection in HCC patients with cirrhosis. Methods: Seventy-seven consecutive HCC patients with cirrhosis underwent non-anatomic liver resection in Tongji Hospital from January 2003 to December 2006. The clinical data, severity of liver cirrhosis, and survival rates of these patients were retrospectively evaluated, and the prognostic factors were analyzed. Results: One-, 2-, and 3-year overall and disease-free survival rates of this cohort of patients were 78%, 68%, 56%, and 66%, 58%, 55%, respectively. The hospital mortality and morbidity were 0% and 24.7%, respectively. The 1-, 2-, and 3-year overall survival rates were 85.7%, 77.1%, and 74.3% in the patients with mild cirrhosis, 81.5%, 63%, and 48.1% in the patients with moderate cirrhosis, and 60.0%, 53.3%, and 26.7% in the patients with severe cirrhosis, respectively. There was a significant difference among the patients with different grades of cirrhosis ( P = 0.001). Multivariate and univariate analyses revealed that severity of cirrhosis, tumor diameter larger than 5 cm, and vascular invasion were independent prognostic factors. Conclusions: Non-anatomic liver resection for HCC could yield comparable outcomes with anatomic resection in the patients with mild cirrhosis or tumors diameter smaller than 5 cm. Severity of cirrhosis is an independent factor worsening long-time survival. Non-anatomic resection is a safe and effective surgical modality in the treatment of HCC patients with cirrhosis. [ABSTRACT FROM AUTHOR]

Postoperative pancreatic fistula (POPF) remains a leading cause of morbidity and mortality after pancreaticoduodenectomy (PD). Thus, a number of technical modifications regarding the pancreato-enteric anastomosis after PD have been proposed to reduce POPF rate. Until now, there is no consensus on which is the best. This study presents a new technique of the end-to-end invaginated pancreaticojejunostomy with two to three transpancreatic U-sutures and evaluates its safety and reliability. From 2002 to 2007, 88 patients (54 men and 34 women) underwent an invaginated end-to-end pancreaticojejunostomy with two to three transpancreatic U-sutures after PD. The mean age was 52.4 years (range, 26–74 years). The diseases of the all patients were malignant. In all patients of this study, two transpancreatic U-sutures were performed in 59 and three U-sutures in 29. The median duration of surgery was 3.8 h (range 3–6.5) and the median time to perform pancreaticojejunostomy was 13.3 min (range 8–25). The median blood loss was 750 ml (range 300–1,800), 36 patients needed transfusion and the median blood transfusion was 380 mL (range 200–1,200). Overall morbidity occurred in 15 patients (17.0%). Only two patients (2.2%) had grade A of POPF and no patient had grade B and grade C of POPF. No operative death occurred. An invaginated end-to-end pancreaticojejunostomy with two to three transpancreatic U-sutures is simple, rapid, safe, and reliable technique, even in some patients with soft pancreas and small pancreatic duct. [ABSTRACT FROM AUTHOR]

Abstract  Chloramphenicol (CAP) residues in carp (Cyprinus carpio L.) were investigated after intramuscular injection of a single-dose of 80 mg/kgbw. CAP concentrations in carp serum and muscle with and without addition of β-glucuronidase were determined by high-performance liquid chromatography (HPLC) with UV detection. The results showed that CAP-glucuronide (CAP-G), an important conjugate of CAP in the metabolic process and potentially toxic to human health, was observed after the fish were injected with CAP. CAP concentrations in serum and muscle with added β-glucuronidase were significantly (p  [ABSTRACT FROM AUTHOR]

Background: Hepatic veins remain patent during complete inflow occlusion (CIO) and bleeding from them may continue. Occlusion of the inferior vena cava (ICV) during CIO may reduce blood loss from hepatic veins. This study was designed to compare the overall outcomes after application of CIO with or without occlusion of the ICV below the liver in complex mesohepatectomy for hepatocellular carcinoma (HCC) patients with cirrhosis. Materials and methods: One hundred and eighteen (118) patients were randomly assigned to CIO or a modified technique of hepatic vascular exclusion (MTHVE). Hemodynamic parameters were evaluated and the amount of blood loss, measurement of liver enzymes, and postoperative progress were recorded. Results: Blood loss during liver transection in CIO groups was significantly greater than that in MTHVE group (P=0.046). Thus, incidence of blood transfusion was significantly greater in patients of the CIO group (P=0.041). There were no significant differences in liver enzyme changes, bilirubin, or morbidity in the postoperative period between the two groups. Conclusions: CIO with occlusion of the ICV below the liver is a safe, effective, and feasible technique during mesohepatectomy in HCC patients with cirrhosis. Excellent results were obtained with minimized bleeding, limited hepatic function damage, and low rate of postoperative complications. [ABSTRACT FROM AUTHOR]

The influence of ball-milling methods on microstructure and mechanical properties of silicon nitride (Si3N4) ceramics produced by pressureless sintering for a sintering additive from MgO–Al2O3–SiO2 system was investigated. For planetary high-energy ball milling, the mechanical properties of Si3N4 ceramics were evidently improved and a homogeneous microstructure developed. In contrast, some exaggerated elongated grains were developed due to the local enrichment of sintering additives in the specimen prepared by general ball milling. For Si3N4 ceramics produced by planetary ball milling, flexure strength of 1.06 GPa, Vickers hardness of 14.2 GPa, and fracture toughness of 6.6 MPa·m0.5 were achieved. The differences in the mechanical properties of Si3N4 ceramics produced by different processing seem to arise mainly from the changes in microstructural homogenization and sinterability. The planetary high-energy ball-milling process provides a good route to mix starting powders for developing ceramics with uniform microstructure and promising mechanical properties. [ABSTRACT FROM AUTHOR]

The multi-metal-binding MT fractions in rat tissues after oral intake of cinnabar were characterized by hyphenated size-exclusion chromatography (SEC) and inductively coupled plasma mass spectrometry (ICP–MS). With the increase of both the feeding time and dosage of cinnabar the amounts of Hg-binding MT fractions in rat kidney of groups fed cinnabar increased significantly compared with the control group. Meanwhile, more Cu-binding MT were synthesized in the rat kidney, which confirmed the manipulating effect of MT in the homeostasis of Cu for detoxification of nephritic mercury. Although the Hg-binding MT fractions in rat liver of all cinnabar groups were almost independent of cinnabar dosage (2.5–5.0 g kg-1 bw) and feeding time (2–4 weeks), the amount was much higher than that of the control group. The amounts of Hg-MT in other rat tissues of the cinnabar groups and the control group were compared and their significance is discussed. [ABSTRACT FROM AUTHOR]

Members of the cadherin family have been implicated as growth regulators in multiple tumor types. Based on recent studies from our laboratory implicating T-cadherin expression in mouse brain tumorigenesis, we examined the role of T-cadherin in astrocytoma growth regulation. In this report, we show that T-cadherin expression increased during primary astrocyte physiologic growth arrest in response to contact inhibition and serum starvation in vitro, suggesting a function for T-cadherin in astrocyte growth regulation. We further demonstrate that transient and stable reexpression of T-cadherin in deficient C6 glioma cell lines results in growth suppression. In addition, T-cadherin-expressing C6 cell lines demonstrated increased homophilic cell aggregation, increased cell attachment to fibronectin, and decreased cell motility. Cell cycle flow cytometry demonstrated that T-cadherin reexpression resulted in G[sub 2] phase arrest, which was confirmed by mitotic index analysis. This growth arrest was p53 independent, as T-cadherin could still mediate growth suppression in p53[sup -/-] mouse embryonic fibroblasts. T-cadherin-expressing C6 cell lines exhibited increased p21[sup CIP1/WAF1], but not p27[sup Kip1], expression. Lastly, T-cadherin-mediated growth arrest was dependent on p21[sup CIP1/WAF1] expression and was eliminated in p21[sup CIP1/WAF1]-deficient fibroblasts. Collectively, these observations suggest a novel mechanism of growth regulation for T-cadherin involving p21[sup CIP1/WAF1] expression and G[sub 2] arrest. [ABSTRACT FROM AUTHOR]

Presents a study that determined whether CDK4 overexpression provides a cooperative growth advantage in vitro for the formation of malignant gliomas. Results; Discussion; Methodology.

Three experiments were conducted to explore the effects of severe food shortage on the control of two important and interrelated aspects of temporal division of labor in colonies of the honey bee ( Apis mellifera): the size and age distribution of a colony's foraging force. The experiments were conducted with single-cohort colonies, composed entirely of young bees, allowing us to quickly distinguish the development of new (precocious) foragers from increases in activity of bees already competent to forage. In experiment 1, colony food shortage caused an acceleration of behavioral development; a significantly greater proportion of bees from starved colonies than from fed colonies became precocious foragers, and at significantly younger ages. Temporal aspects of this starvation effect were further explored in experiment 2 by feeding colonies that we initially starved, and starving colonies that we initially fed. There was a significant decrease in the number of new foragers in starved colonies that were fed, detected 1 day after feeding. There also was a significant increase in the number of new foragers in fed colonies that were starved, but only after a 2-day lag. These results suggest that colony nutritional status does affect long-term behavioral development, rather than only modulate the activity of bees already competent to forage. In experiment 3, we uncoupled the nutritional status of a colony from that of the individual colony members. The behavior of fed individuals in starved colonies was indistinguishable from that of bees in fed colonies, but significantly different from that of bees in starved colonies, in terms of both the number and age distribution of foragers. These results demonstrate that effects of starvation on temporal polyethism are not mediated by the most obvious possible worker-nest interaction: a direct interaction with colony food stores. This is consistent with previous findings suggesting the importance of worker-worker interactions in the regulation of temporal polyethism in honey bees as well as other social insects. [ABSTRACT FROM AUTHOR]

Presents updates on the operations of the International Hepato-Pancreato-Biliary Association in the U.S. as of May 2005. Increase in the number of members of the association; Renewal of the management contract between the association and Medconnect; Introduction of an electronic newsletter in December 2005.

We carried out a proof-of-principle demonstration of the reconstruction of a static vector magnetic field involving adjacent three nitrogen-vacancy (NV) sensors with corresponding different NV symmetry axes in a bulk diamond. By means of optical detection of the magnetic resonance (ODMR) techniques, our experiment employs the continuous wave (CW) to monitor resonance frequencies and it extracts the information of the detected field strength and polar angles with respect to each NV frame of reference. Finally, the detected magnetic field relative to a fixed laboratory reference frame was reconstructed from the information acquired by the multi-NV sensor. [ABSTRACT FROM AUTHOR]

We suggest an experimental scheme that a single nitrogen-vacancy (NV) center coupled to a nearest neighbor 13C nucleus as a sensor in diamond can be used to detect a static vector magnetic field. By means of optical detection magnetic resonance (ODMR) technique, both the strength and the direction of the vector field could be determined by relevant resonance frequencies of continuous wave (CW) and Ramsey spectrums. In addition, we give a method that determines the unique one of eight possible hyperfine tensors for an (NV–13C) system. Finally, we propose an unambiguous method to exclude the symmetrical solution from eight possible vector fields, which correspond to nearly identical resonance frequencies due to their mirror symmetry about 14N–Vacancy–13C (14N–V–13C) plane. [ABSTRACT FROM AUTHOR]

The surrounding environment of rivers in city is often damaged and polluted.How to effectively monitor rivers has gradually attracted the attention of public,government and academia.At present,traditional monitoring methods are facing with high cost,insufficient coverage and other defects.With the increasing popularity of intelligent mobile devices,a new idea of using crowd sensing to efficiently monitor the river environment is proposed in this paper.The problem can be described as the assumption that each river reach contains c monitoring points,and then r users are selected according to the movement tracks of a large number of users to jointly complete the monitoring of all river reaches in s periods.It is stipulated that the smaller the number of users r,the less the monitoring cost.The stepwise-greedy strategy,the global-greedy strategy and the integer-programming stra-tegy are designed to solve this problem,that is,to select the least number of participants to achieve the monitoring goal of “s durations-c ranges-r users”.In this paper,the above strategies are applied to environmental monitoring of some rivers in Taijiang,Fuzhou.Experimental results show that the above strategies can obtain better solutions than the random strategy,and the integer-programming strategy has the best performance.However,with the increase of the scale of the problem,the implicit enumeration algorithm used to solve the small-scale integer programming will be unable to solve the situation.Motivated by this,this paper designs a discrete particle swarm optimization algorithm based on greedy initialization(GI-DPSO).Although this algorithm can solve large-scale integer programming,it is time-consuming.Considering the monitoring cost and computational cost comprehensively,it is suggested that the integer-programming strategy can be adopted for small-scale problems and the global-greedy strategy can be adopted for large-scale problems.

Background Our previous study suggested that N-cadherin was downregulated in hepatocellular carcinoma (HCC). Our aim in this study was to investigate the correlation between N- and E-cadherin expression in HCC and its clinical significance. Methods Eighty-six patients with HCC undergoing liver resection were retrospectively studied. N- and E-cadherin expression in HCC and adjacent liver tissue were investigated using immunohistochemistry and immunofluorescence. The correlation between the expression status of both cadherins and surgical outcomes was analyzed. Results In 23 patients negative for E-cadherin expression, 19 of them (82.6%) were also negative for N-cadherin expression. In 30 patients with heterogeneous expression of E-cadherin, 20 of them (66.7%) also had heterogeneous expression of N-cadherin. In 33 patients with uniformly positive expression of E-cadherin, 19 of them (57.6%) also had uniformly positive expression of N-cadherin. Therefore, there was a positive correlation between expression patterns of N- and E-cadherins. Concurrent loss of both N- and E-cadherin expressions was significantly associated with absence of the tumor capsule, vascular invasion, and poor differentiation. The 1- and 3-y disease-free survival rates were 27% and 9%, respectively, and the 1- and 3-y overall survival rates were 64.3% and 14.3%, respectively, in patients with concurrent loss of both cadherins, which were significantly worse than those with concurrent uniformly positive expression or heterogeneous expression of both cadherins. Conclusions Loss of N-cadherin was positively correlated with loss of E-cadherin in HCC. Concurrent loss of both N- and E-cadherin expressions was associated with poor surgical outcomes of HCC patients undergoing liver resection. [ABSTRACT FROM AUTHOR]

Background: The fact that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces profound apoptosis in a wide range of tumor cell lines but lacks cytotoxicity to mosnormal cells raises hope that TRAIL might become a novel potential anticancer agent. Our previous studies shown that hepatoma cells are not sensitive to TRAIL treatment . Overexpression of survivin reduced sensitivity of hepatoma cells to TRAIL.The aim of this study is to investigate whether tumor cells escape TRAIL-killing through survivin experssion and how to reverse this resistance. Methods: Human hepatoma cell lines (HepG2, SMMC 7721), cholangiocarcinoma cell line QBC939, no-small-cell lung cancer cell line A549, colorectal adenocarcinoma cell lines (SW480 and HCT-15), and malignant hematopoietic cell line Jurkat, were treated with or without TRAIL protein and survivin antisense oligodeoxynucleotide (ODN) in culture. Survivin mRNA levels in treated cells were detected by semiquantitative RT-PCR. Synchronization of hepatoma cells was used to test the sensitivity of hepatoma cells to TRAIL. Apoptosis and cell cycle were examined by flow cytometry. Cell viability and proliferation assay were evaluated by MTT. In vivo effects of TRAIL plasmid and /or survivin antisense ODN on tumor growth were investigated in a nude mouse HCC model of HepG2 cell grafts in the liver. Results: Survivin mRNA levels varied in cell lines evaluated and negatively correlated to TRAIL-induced apoptosis (r=−0.856,p<0.05).HepG2 and SMMC-7721 in G1 or S phase are more sensitive to TRAIL than those in G2 phase. Treatment with survivin antisence ODN caused S arrest and significantly enhanced TRAIL-killing.Treatment with TRAIL protein caused G2/M arrest and resulted in an increase in survivin protein levels in HepG2 cells.Combined intratumoral injection of TRAIL plasmid and survivin antisense ODN significantly supressed the growth of tumor xenografts in nude mice as compared to TRAIL plamid alone (0.31±0.05 vs 2.35 ±0.38 cm3, P <0.01) during a 4-week of observation. Conclusions: The findings indicate that survivin may play a role in tumor cell resistance to TRAIL-induced apoptosis, at least in part, through cell cycle regulation. Manipulation of survivin expression may sensitizes HCC to TRAIL-induced apoptosis. This approach may offer a novel approach in molecular therapy against HCC for which no effective treatment is available for an advanced stage.Molecular Therapy (2006) 13, S364–S365; doi: 10.1016/j.ymthe.2006.08.1035 [ABSTRACT FROM AUTHOR]