A 28 GHz 0.18-μm CMOS cascade power amplifier with reverse body bias technique

A 28 GHz power amplifier (PA) using CMOS 0.18 μm Silterra process technology is reported. The cascade configuration has been adopted to obtain high Power Added Efficiency (PAE). To achieve low power consumption, the input stage adopts reverse body bias technique. The simulation results show that the proposed PA consumes 32.03mW and power gain (S21) of 9.51 dB is achieved at 28 GHz. The PA achieves saturated power (Psat) of 11.10 dBm and maximum PAE of 16.55% with output 1-dB compression point (OP1dB) 8.44 dBm. These results demonstrate the proposed power amplifier architecture is suitable for 5G applications

Analysis of signal propagation in an experiment room with epoxy covered floor for wireless sensor network applications

As sensor applications combined with wireless network becoming more of an everyday applications, the optimal deployment becomes ever increasing important as that would be a key important factor in the trade-off between cost and link quality. This paper reports on the effect of epoxy covered floor on signal propagation characteristics in an experiment room. Microchip developed motes were used to measure signal propagation in an experiment room where sensors would be deployed extensively. The results show that the signal strength for 30 cm antenna height provides a significant margin with respect to signal noise floor. As for the 5 cm antenna height, there is still around 25 dB margin in average before the signal reaches noise floor. Analysis shows that the log-distance model is the best fit to the measured data. Free Space Loss model seemed to under estimate the overall performance of the signals. An important conclusion from this study is that wireless mote deployment must consider the margin between the two signals of antenna heights and the margin to noise floor to avoid link quality deterioration especially for sensitive data acquisition applications

Sustainability assessment framework: a mini review of assessment concept

Sustainability assessment is viewed as a vital instrument to aid in the shift towards sustainability which is simply an appraisal method which integrates an iterative and pluralistic procedure. Sustainability assessment is viewed as a vital instrument to aid in the shift towards sustainability. Sustainability assessment is a rather complex appraisal technique conducted for supporting decision-making and policy in an extensive environmental, economic and social perspective. Sustainability assessment transcends a technical or scientific evaluation. Sustainability assessment tools are essentially a structured process encompassing different field-specific analytical methods and models. The growth of indicators in numerous fields has influenced sustainability assessment methodologies to a great extent. In general two broad approaches for sustainability can be distinguished, top-down and bottom-up. Despite the abundance and diversified procedures for evaluating sustainability, indicators based assessment is one of the most widely used platform. Many parties feel that the presence of conceptual inconsistencies and the absence of operational definitions have hampered attempts to appraise, let alone achieve, sustainability. Assessing the sustainability assessment schemes in a quantitative manner requires the identification and integration of diverse phenomena or indicators, in a framework consistent with the evolving concept of sustainability. In fact, integration of indicators for sustainability assessment, have been at the forefront of various political, academic and scientific researches. Existing sustainability assessments schemes typically provide interpretation in the form of comparative value analysis where impacts are scored based on pre-set values, utility analysis where impacts are ranked on a uniform scale and weighted, cost-benefit analysis where positive and negative impacts are apportioned to monetary values, multi-criteria analysis where quantitative as well as qualitative impacts are scaled on pre-set criteria or risk assessment where degrees in risk reduction is identified relative to pre-set risk thresholds. Consequently, the paper that follows provides an integrative analysis of existing sustainability assessment approaches. Such review not only offers a very valuable insight on the features of existing sustainability assessment schemes, but also highlighting gaps to a certain extent

A sustainability performance assessment framework for palm oil mills

The palm oil industry has had to undergo rapid development in order to cope with the increasing demand from consumers year by year. The palm oil industry is receiving criticism from various parties on the issue of sustainability. This paper presents the development of a Palm Oil Mill Sustainability Index that enables millers to assess the sustainability performance of palm oil mills against benchmarks, and to differentiate between the performance of each mill. The assessment was performed via the adoption of a Proximity-to-Target approach that measures the current sustainability performance of the industry relative to policy targets. The industry's comparable performance was observed in terms of sustainability and indicators through a graphical method. The resulting Palm Oil Mill Sustainability Index scores were translated into a five-point rating system to describe the sustainability performance levels for different mills i.e. excellent, good, fair, poor, and very poor. Based on the Palm Oil Mill Sustainability Index scores and rating system, weak performance indicators were identified, for example, excessive use of water consumption due to inappropriate operation of hydrocyclones. By identifying the weak performance indicators, practical recommendations and measures for improvement can be proposed and the Palm Oil Mill Sustainability Index scores recalculated to evaluate the effectiveness of the proposed sustainability performance strategy. Selected palm oil mills in Malaysia were used as a case study to demonstrate the applicability of the framework. The results provide empirical evidence to support a decision-support-system for enhancing palm oil mill sustainability performance, so as to achieve a balance between environmental, economic, and social aspects in the palm oil mill sector

Current practice of early leak detection methods for underground storage tanks

This article aims to provide general review on current practice of leak detection methods of underground storage tanks (UST). Fuel (i.e. gasoline and diesel oil) leakage from UST can contaminate groundwater and drinking water with various hydrocarbon contaminants. These leaks create ponds of fuel that spill into the land and aquifers, polluting and seriously destroying habitats. Numerous efforts have been focused on the development of leak detection to the tanks. However, without the opportunity to conduct fault intensity calibration and estimate a product's lifetime, there is a lack of information provided to consider the condition of previous underlying leakage. As a result, it is too late whether the harm has already been done. There are methods of detection that have been studied for the past ten years. Many approaches have been practised to detect leakage. Specific sensing devices will combine with additional applications that analyse and interpret the data to detect storage tank leaks. Various methods will provide different results depending on the feature chosen. Some approaches will use machine learning to analyse the provided data and provide the best leak detection result. This paper will explore the best leak detection techniques to improve underground tanks' structural integrity. At the end, this paper will give some overview on current practice early detection methods on underground storage tanks for future research

No Association of Xenotropic Murine Leukemia Virus-Related Viruses with Prostate Cancer

BACKGROUND: The association of the xenotropic murine leukemia virus-related virus (XMRV) with prostate cancer continues to receive heightened attention as studies report discrepant XMRV prevalences ranging from zero up to 23%. It is unclear if differences in the diagnostic testing, disease severity, geography, or other factors account for the discordant results. We report here the prevalence of XMRV in a population with well-defined prostate cancers and RNase L polymorphism. We used broadly reactive PCR and Western blot (WB) assays to detect infection with XMRV and related murine leukemia viruses (MLV). METHODOLOGY/PRINCIPAL FINDINGS: We studied specimens from 162 US patients diagnosed with prostate cancer with a intermediate to advanced stage (Gleason Scores of 5-10; moderate (46%) poorly differentiated tumors (54%)). Prostate tissue DNA was tested by PCR assays that detect XMRV and MLV variants. To exclude contamination with mouse DNA, we also designed and used a mouse-specific DNA PCR test. Detailed phylogenetic analysis was used to infer evolutionary relationships. RNase L typing showed that 9.3% were homozygous (QQ) for the R462Q RNase L mutation, while 45.6% and 45.1% were homozygous or heterozygous, respectively. Serologic testing was performed by a WB test. Three of 162 (1.9%) prostate tissue DNA were PCR-positive for XMRV and had undetectable mouse DNA. None was homozygous for the QQ mutation. Plasma from all three persons was negative for viral RNA by RT-PCR. All 162 patients were WB negative. Phylogenetic analysis inferred a distinct XMRV. CONCLUSIONS AND THEIR SIGNIFICANCE: We found a very low prevalence of XMRV in prostate cancer patients. Infection was confirmed by phylogenetic analysis and absence of contaminating mouse DNA. The finding of undetectable antibodies and viremia in all three patients may reflect latent infection. Our results do not support an association of XMRV or MLV variants with prostate cancer

Hyphal Development in Candida albicans Requires Two Temporally Linked Changes in Promoter Chromatin for Initiation and Maintenance

Phenotypic plasticity is common in development. For Candida albicans, the most common cause of invasive fungal infections in humans, morphological plasticity is its defining feature and is critical for its pathogenesis. Unlike other fungal pathogens that exist primarily in either yeast or hyphal forms, C. albicans is able to switch reversibly between yeast and hyphal growth forms in response to environmental cues. Although many regulators have been found involved in hyphal development, the mechanisms of regulating hyphal development and plasticity of dimorphism remain unclear. Here we show that hyphal development involves two sequential regulations of the promoter chromatin of hypha-specific genes. Initiation requires a rapid but temporary disappearance of the Nrg1 transcriptional repressor of hyphal morphogenesis via activation of the cAMP-PKA pathway. Maintenance requires promoter recruitment of Hda1 histone deacetylase under reduced Tor1 (target of rapamycin) signaling. Hda1 deacetylates a subunit of the NuA4 histone acetyltransferase module, leading to eviction of the NuA4 acetyltransferase module and blockage of Nrg1 access to promoters of hypha-specific genes. Promoter recruitment of Hda1 for hyphal maintenance happens only during the period when Nrg1 is gone. The sequential regulation of hyphal development by the activation of the cAMP-PKA pathway and reduced Tor1 signaling provides a molecular mechanism for plasticity of dimorphism and how C. albicans adapts to the varied host environments in pathogenesis. Such temporally linked regulation of promoter chromatin by different signaling pathways provides a unique mechanism for integrating multiple signals during development and cell fate specification

Magnetic resonance imaging (MRI) contrast agents for tumor diagnosis

10.1260/2040-2295.4.1.23Journal of Healthcare Engineering4123-4