Analisa Perbandingan Algoritma DCT, Haar Wavelet, Huffman dan LZW pada Kompresi Citra Digital Menggunakan Matlab R2013a

Digital image compression is an important method for data transmission and data storage more efficient. There are two compression techniques used are; lossless compression and lossy compression. In lossless compression technique using Huffman and LZW whereas lossy compression technique using the DCT and Wavelet Haar. At any given algorithm image insert 2 input object image is varied according to four dimensions (320x480, 480x640, 640x720, 720x1080) and 4 format (BMP, GIF, PNG and TIFF). the result of applying the algorithm generates the MSE will be used as a comparison. The result of the application of simulation shows the lossy compression format GIF has the largest MSE of the other formats with MSE value is in the range of 16,4 to 20 dB

L-arginase induces vascular dysfunction in old spontaneously hypertensive rats

Background: Aging is a major non-modifiable risk factor for hypertension. Changes in aging are similar to those seen in hypertension in the vasculature. Also, aging increases the vascular dysfunction that occurs in hypertension. L-arginase action reduces substrate (L-arginine) availability for the formation of nitric oxide (NO). This reduces the level of NO and leads to reduced vasodilation and ultimately, vascular dysfunction. This study examines the hypothesis that age-dependent vascular dysfunction in SHRs is mediated by arginase.Methods: Young (12-14 weeks) and old (11-12 months) male Wistar and spontaneously hypertensive rats (SHR) were used. Mean arterial pressure (MAP) was measured in the rats. They were then euthanized and mesenteric resistance arteries (MRAs) and thoracic aortae were excised and placed in ice-cold physiological salt solution (PSS). Arterial segments were either snap-frozen in liquid nitrogen and stored for immunoblotting studies or cut into 2mm rings for reactivity studies. Cumulative concentration-response curves to acetylcholine (Ach; 10-9 – 3x10-5M) and sodium nitroprusside (SNP; 10-12 – 3x10-5 M) were performed in the absence or presence (30-minute exposure) of L-arginase, 0.05U/ML (MRA) or 0.5U/ML (aorta). Vessels were pre-contracted with phenylephrine (PE; 3x10-6M)Results: MAP increased during aging in the SHRs p<0.05 but not in the Wistar rats. Arginase impaired the endothelium-dependent relaxation responses of thoracic aortic and MRA arterial rings to Ach in the old Wistars and SHRs (Emax aorta: 29.42±2.19% vs 7.94±1.86%). Arginase also impaired endothelium-independent relaxation response to SNP in the old SHRs only (Emax aorta: 88.62±4.10% vs 31.45±10.61%). We also observed no differences in the serum arginase activity in the four groups of rats. On the contrary, arginase activity in the aortae of young Wistar rats was reduced compared to other groups.Conclusions: Arginase impairs both endothelium-dependent and –independent vasorelaxation responses, through the NO signaling pathway.Keywords: Hypertension, Arginase, aging, vascular dysfunction, endothelium, Nitric oxid

Microbial sulfate reduction and metal attenuation in pH 4 acid mine water

Sediments recovered from the flooded mine workings of the Penn Mine, a Cu-Zn mine abandoned since the early 1960s, were cultured for anaerobic bacteria over a range of pH (4.0 to 7.5). The molecular biology of sediments and cultures was studied to determine whether sulfate-reducing bacteria (SRB) were active in moderately acidic conditions present in the underground mine workings. Here we document multiple, independent analyses and show evidence that sulfate reduction and associated metal attenuation are occurring in the pH-4 mine environment. Waterchemistry analyses of the mine water reveal: (1) preferential complexation and precipitation by H2S of Cu and Cd, relative to Zn; (2) stable isotope ratios of 34S/32S and 18O/16O in dissolved SO4 that are 2–3 ‰ heavier in the mine water, relative to those in surface waters; (3) reduction/oxidation conditions and dissolved gas concentrations consistent with conditions to support anaerobic processes such as sulfate reduction. Scanning electron microscope (SEM) analyses of sediment show 1.5-micrometer, spherical ZnS precipitates. Phospholipid fatty acid (PLFA) and denaturing gradient gel electrophoresis (DGGE) analyses of Penn Mine sediment show a high biomass level with a moderately diverse community structure composed primarily of iron- and sulfate-reducing bacteria. Cultures of sediment from the mine produced dissolved sulfide at pH values near 7 and near 4, forming precipitates of either iron sulfide or elemental sulfur. DGGE coupled with sequence and phylogenetic analysis of 16S rDNA gene segments showed populations of Desulfosporosinus and Desulfitobacterium in Penn Mine sediment and laboratory cultures

Molecular evidence for gender differences in the migratory behaviour of a small seabird

Molecular sexing revealed an unexpectedly strong female bias in the sex ratio of pre-breeding European Storm Petrels (Hydrobates pelagicus), attracted to playback of conspecific calls during their northwards migration past SW Europe. This bias was consistent across seven years, ranging from 80.8% to 89.7% female (mean annual sex ratio ± SD = 85.5% female ±4.1%). The sex ratio did not differ significantly from unity (i.e., 50% female) among (i) Storm Petrel chicks at a breeding colony in NW France, (ii) adults found dead on beaches in Southern Portugal, (iii) breeding birds attending nest burrows in the UK, captured by hand, and (iv) adults captured near a breeding colony in the UK using copies of the same sound recordings as used in Southern Europe, indicating that females are not inherently more strongly attracted to playback calls than males. A morphological discriminant function analysis failed to provide a good separation of the sexes, showing the importance of molecular sexing for this species. We found no sex difference in the seasonal or nocturnal timing of migration past Southern Europe, but there was a significant tendency for birds to be caught in sex-specific aggregations. The preponderance of females captured in Southern Europe suggests that the sexes may differ in migration route or in their colony-prospecting behaviour during migration, at sites far away from their natal colonies. Such differences in migration behaviour between males and females are poorly understood but have implications for the vulnerability of seabirds to pollution and environmental change at sea during the non-breeding season

In Vitro and In Vivo Evidence for Lack of Endovascular Remodeling by Third Trimester Trophoblasts

The placental–decidual interaction through invading trophoblasts determines whether a physiological transformation of the uterine spiral arteries is established or not. Trophoblast-orchestrated artery remodeling is central to normal placentation. Dysregulated uteroplacental interaction and vascular remodeling are thought to be associated with the molecular events underlying the pathology of late pregnancy anomalies including preeclampsia. Although the exact gestational age at which trophoblast invasion ceases is not known, it remains unclear whether late pregnancy trophoblasts retain the ability to transform the uterine arteries. Here, we have developed a dual cell, in vitro culture system that mimics the vascular remodeling events during normal pregnancy. We demonstrate that first and third trimester trophoblasts respond differentially to interactive signals from endothelial cells when cultured on matrigel. Term primary trophoblasts or immortalized third trimester extravillous TCL1 trophoblasts not only fail to respond to signals from endothelial cells but also inhibit endothelial cell tube formation. In contrast, HTR8 cells, representing a first trimester trophoblast cell line with invasive properties, undergo spontaneous migration and synchronize with the endothelial cells in a capillary network. This disparity in behavior was confirmed in vivo using a matrigel plug assay. Poor expression of VEGF C and VEGF receptors coupled with high E-cadherin expression by term primary trophoblasts and TCL1 cells contributed to their restricted interactive and migratory properties. We further show that the kinase activity of VEGF R2 is essential for proactive crosstalk by HTR8 cells. This unique behavior of first trimester trophoblasts in the presence of endothelial cells offers a potential approach to study cell–cell interactions and to decipher modulatory components in the serum samples from adverse pregnancy outcomes

Septin-2 is overexpressed in epithelial ovarian cancer and mediates proliferation via regulation of cellular metabolic proteins

Epithelial Ovarian Cancer (EOC) is associated with dismal survival rates due to the fact that patients are frequently diagnosed at an advanced stage and eventually become resistant to traditional chemotherapeutics. Hence, there is a crucial need for new and innovative therapies. Septin-2, a member of the septin family of GTP binding proteins, has been characterized in EOC for the first time and represents a potential future target. Septin-2 was found to be overexpressed in serous and clear cell human patient tissue compared to benign disease. Stable septin-2 knockdown clones developed in an ovarian cancer cell line exhibited a significant decrease in proliferation rates. Comparative label-free proteomic analysis of septin-2 knockdown cells revealed differential protein expression of pathways associated with the TCA cycle, acetyl CoA, proteasome and spliceosome. Further validation of target proteins indicated that septin-2 plays a predominant role in post-transcriptional and translational modifications as well as cellular metabolism, and suggested the potential novel role of septin-2 in promoting EOC tumorigenesis through these mechanisms

Inhibition of DUSP6 sensitizes ovarian cancer cells to chemotherapeutic agents via regulation of ERK signaling response genes

Dual specificity phosphatase 6 (DUSP6) is a protein phosphatase that deactivates extracellular-signal-regulated kinase (ERK). Since the ovarian cancer biomarker human epididymis protein 4 (HE4) interacts with the ERK pathway, we sought to determine the relationship between DUSP6 and HE4 and elucidate DUSP6’s role in epithelial ovarian cancer (EOC). Viability assays revealed a significant decrease in cell viability with pharmacological inhibition of DUSP6 using (E/Z)-BCI hydrochloride in ovarian cancer cells treated with carboplatin or paclitaxel, compared to treatment with either agent alone. Quantitative PCR was used to evaluate levels of ERK pathway response genes to BCI in combination with recombinant HE4 (rHE4), carboplatin, and paclitaxel. Expression of EGR1, a promoter of apoptosis, was higher in cells co-treated with BCI and paclitaxel or carboplatin than in cells treated with chemotherapeutic agents alone, while expression of the proto-oncogene c-JUN was decreased with co-treatment. The effect of BCI on the expression of these two genes opposed that of rHE4. Pathway focused quantitative PCR also revealed suppression of ERBB3 in cells co-treated with BCI plus carboplatin or paclitaxel. Finally, expression levels of DUSP6 in EOC tissue were evaluated by immunohistochemistry, revealing significantly increased levels of DUSP6 in serous EOC tissue compared to adjacent normal tissue. A positive correlation between HE4 and DUSP6 levels was determined by Spearman Rank correlation. In conclusion, DUSP6 inhibition sensitizes ovarian cancer cells to chemotherapeutic agents and alters gene expression of ERK response genes, suggesting that DUSP6 could plausibly function as a novel therapeutic target to reduce chemoresistance in EOC

Europe-wide air pollution modeling from 2000 to 2019 using geographically weighted regression

Previous European land-use regression (LUR) models assumed fixed linear relationships between air pollution concentrations and predictors such as traffic and land use. We evaluated whether including spatially-varying relationships could improve European LUR models by using geographically weighted regression (GWR) and random forest (RF). We built separate LUR models for each year from 2000 to 2019 for NO2, O3, PM2.5 and PM10 using annual average monitoring observations across Europe. Potential predictors included satellite retrievals, chemical transport model estimates and land-use variables. Supervised linear regression (SLR) was used to select predictors, and then GWR estimated the potentially spatially-varying coefficients. We developed multi-year models using geographically and temporally weighted regression (GTWR). Five-fold cross-validation per year showed that GWR and GTWR explained similar spatial variations in annual average concentrations (average R(2) = NO2: 0.66; O3: 0.58; PM10: 0.62; PM2.5: 0.77), which are better than SLR (average R(2) = NO2: 0.61; O3: 0.46; PM10: 0.51; PM2.5: 0.75) and RF (average R(2) = NO2: 0.64; O3: 0.53; PM10: 0.56; PM2.5: 0.67). The GTWR predictions and a previously-used method of back-extrapolating 2010 model predictions using CTM were overall highly correlated (R(2) > 0.8) for all pollutants. Including spatially-varying relationships using GWR modestly improved European air pollution annual LUR models, allowing time-varying exposure-health risk models

Underground railroads: citizen entitlements and unauthorized mobility in the antebellum period and today

In recent years, some scholars and prominent political figures have advocated the deepening of North American integration on roughly the European Union model, including the creation of new political institutions and the free movement of workers across borders. The construction of such a North American Union, if it included even a very thin trans-state citizenship regime, could represent the most significant expansion of individual entitlements in the region since citizenship was extended to former slaves in the United States. With such a possibility as its starting point, this article explores some striking parallels between the mass, legally prohibited movement across boundaries by fugitive slaves in the pre-Civil War period, and that by current unauthorized migrants to the United States. Both were, or are, met on their journeys by historically parallel groups of would-be helpers and hinderers. Their unauthorized movements in both periods serve as important signals of incomplete entitlements or institutional protections. Most crucially, moral arguments for extending fuller entitlements to both groups are shown here to be less distinct than may be prima facie evident, reinforcing the case for expanding and deepening the regional membership regime