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Tunable multiband microstrip antenna for 5GHz WLAN
Copyright @ 2013. Ali Ejaz, R. Nilavalan & Hattan Abutarboush. This is a research/review paper, distributed under the terms of the
Creative Commons Attribution-Noncommercial 3.0 Unported License http://creativecommons.org/licenses/by-nc/3.0/), permitting
all non commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.In
this paper, a tunable Multiband Micro strip Antenna is designed, capable of tuning its
operating frequency in 5GHz band independently. Two slots of E & U shape are etched to
achieve multiband resonance. Two capacitors of fixed value and a varactor diode are used to
achieve tuning. Proposed antenna targets the 5GHz WLAN bands; UNII-1 and UNII-2. Simulated
and measured results are in good agreement
Interleaving Gains for Receive Diversity Schemes of Distributed Turbo Codes in Wireless Half–Duplex Relay Channels
This paper proposes the interleaving gain in two different distributed turbo-coding schemes: Distributed Turbo Codes (DTC) and Distributed Multiple Turbo Codes (DMTC) for half-duplex relay system as an extension of our previous work on turbo coding interleaver design for direct communication channel. For these schemes with half-duplex constraint, the source node transmits its information with the parity bit sequence(s) to both the relay and the destination nodes during the first phase. The relay received the data from the source and process it by using decode and forward protocol. For the second transmission period, the decoded systematic data at relay is interleaved and re-encoded by a Recursive Systematic Convolutional (RSC) encoder and forwarded to the destination. At destination node, the signals received from the source and relay are processed by using turbo log-MAP iterative decoding for retrieving the original information bits. We demonstrate via simulations that the interleaving gain has a large effect with DTC scheme when we use only one RSC encoder at both the source and relay with best performance when using Modified Matched S-Random (MMSR) interleaver. Furthermore, by designing a Chaotic Pseudo Random Interleaver (CPRI) as an outer interleaver at the source node instead of classical interleavers, our scheme can add more secure channel conditions
Influence of solvent molecular geometry on the growth of nanostructures
Solvent properties such as surface tension, dielectric constant, and viscosity have been extensively studied over more than 150 years to understand their influence on the growth kinetics of nanostructures. Interestingly, these nanoparticles-based studies have missed the influence of solvent molecular geometry. Herein, by synthesizing ZnO nanorods on a highly conductive nitrogen incorporated graphene oxide (N-GO) substrate, we present the first study showing the influence of solvent molecular geometry on the growth mechanism of nanostructures. The solvents such as water (N-GO-ZnO-W) allow a large number of functional atoms along a, b and c-axis to coordinate in all possible directions with the metal ions of wurtzite hexagonal crystal system of ZnO and thus leads to lower aspect ratio nanorods. On the contrary, the unavailability of binding sites along a-axis for solvents such as ethanol (N-GO-ZnO-E) provides a size-limiting effect and leads to preferred growth along b and c-axis, thus generating ZnO nanorods with a higher aspect ratio. The study shows that the number of interacting atoms, carbon chain length and the solvent molecular geometry influence the aspect ratio and therefore a solvent could be used to tune the nanostructures morphology and hence the performance of devices based on them
Spatial and temporal assessment of groundwater recharge in the Fordwah Eastern Sadiqia (South) Project area
Irrigation programs / Drainage / Groundwater / Monitoring / Recharge / Aquifers / Water table / Irrigation systems / Irrigation canals / Waterlogging / Pakistan / Indus Basin / Fordwah Eastern Sadiqia
Community acquired and post-transfusion hepatitis C is there a difference?
We analyzed 77 consecutive hepatitis C antibody positive patients to compare the history, laboratory data and histological features of community acquired (CA) and post-transfusion (PT) hepatitis C. Forty-six patients had CA and 31 PT hepatitis C. Mean age in both groups was same (45.67 vs 46 years). Male to female ratio was 2:1 in the CA group and 1:2.4 in the PT group. Mean duration between jaundice and first presentation was 8.9 years in the CA group and the mean duration between transfusion and first presentation was 9.8 years in PT group. No significant difference was found between two groups in the laboratory data. Liver biopsy was done in 32 patients (19 CA and 13 PT group). Mean histological score for disease activity was 9.3 in both groups, although more (68%) patients in the CA group had cirrhosis with chronic active hepatitis, (CAH) as compared to the PT (54%) group. Hepatitis C is an important cause of CA hepatitis. PT hepatitis C is more common in females because of increased likelihood of receiving transfusion for obstetric and gynaecological reasons. There is no significant difference in the laboratory and histological features between CA and PT hepatitis C
Efficient Circular Repeated Measurements Designs Nearly Strongly Balanced for Carryover Effects
Repeated measurements designs (RMDs) are always economical but with the use of these designs, there may arise carryover effects. Minimal strongly balanced RMDs are well known to estimate the treatment effects and carryover effects independently. Where these minimal designs cannot be constructed, minimal nearly strongly balanced RMDs are used to balance the carryover effects. In this article, efficient circular nearly strongly balanced RMDs are constructed in periods of two and three different sizes with the smallest of size four
Beta2-adrenoceptor agonists for dysmenorrhoea
Background:Dysmenorrhoea is a common gynaecological complaint that can affect as many as 50% of premenopausal women, 10% of whom suffer severely enough to be rendered incapacitated for one to three days during each menstrual cycle. Primary dysmenorrhoea is where women suffer from menstrual pain but lack any pathology in their pelvic anatomy. Beta2-adrenoceptor agonists have been used in the treatment of women with primary dysmenorrhoea but their effects are unclear.Objectives:To determine the effectiveness and safety of beta2-adrenoceptor agonists in the treatment of primary dysmenorrhoea. Search methods: We searched the Cochrane Menstrual Disorders and Subfertility Group Specialised Register, CENTRAL (The Cochrane Library 2011, Issue 8), MEDLINE, EMBASE, PsycINFO and the EBM Reviews databases. The last search was on 22 August 2011.Selection criteriaRandomised controlled trials comparing beta2-adrenoceptor agonists with placebo or no treatment, each other or any other conventional treatment in women of reproductive age with primary dysmenorrhoea. Data collection and analysisTwo review authors independently assessed trial quality and extracted the data.Main results:Five trials involving 187 women with an age range of 15 to 40 years were included. Oral isoxsuprine was compared with placebo in two trials, terbutaline oral spray, ritodrine chloride and oral hydroxyphenyl-orciprenalin were compared with placebo in a further three trials. Clinical diversity in the studies in terms of the interventions being evaluated, assessments at different time points and the use of different assessment tools mitigated against pooling of outcome data across studies in order to provide a summary estimate of effect for any of the comparisons. Only one study, with unclear risk of bias, reported pain relief with a combination of isoxsuprine, acetaminophen and caffeine. None of the other studies reported any significant clinical difference in effectiveness between the intervention and placebo. Adverse effects were reported with all of these medications in up to a quarter of the total number of participants. They included nausea, vomiting, dizziness, quivering, tremor and palpitations.Authors\u27 conclusions:The evidence presented in this review was based on a few relatively small-sized studies that were categorised to have unclear to high risk of bias, which does not allow confident decision-making at present about the use of beta2-adrenoceptor agonists for dysmenorrhoea. The benefits as reported in one study should be balanced against the wide array of unacceptable side effects documented with this class of medication. We have emphasised the lack of precision and limitations in the reported data where appropriate
Single-molecule fluorescence multiplexing by multi-parameter spectroscopic detection of nanostructured FRET labels
Multiplexed, real-time fluorescence detection at the single-molecule level is
highly desirable to reveal the stoichiometry, dynamics, and interactions of
individual molecular species within complex systems. However, traditionally
fluorescence sensing is limited to 3-4 concurrently detected labels, due to low
signal-to-noise, high spectral overlap between labels, and the need to avoid
dissimilar dye chemistries. We have engineered a palette of several dozen
fluorescent labels, called FRETfluors, for spectroscopic multiplexing at the
single-molecule level. Each FRETfluor is a compact nanostructure formed from
the same three chemical building blocks (DNA, Cy3, and Cy5). The composition
and dye-dye geometries create a characteristic F\"orster Resonance Energy
Transfer (FRET) efficiency for each construct. In addition, we varied the local
DNA sequence and attachment chemistry to alter the Cy3 and Cy5 emission
properties and thereby shift the emission signatures of an entire series of
FRET constructs to new sectors of the multi-parameter detection space. Unique
spectroscopic emission of each FRETfluor is therefore conferred by a
combination of FRET and this site-specific tuning of individual fluorophore
photophysics. We show single-molecule identification of a set of 27 FRETfluors
in a sample mixture using a subset of constructs statistically selected to
minimize classification errors, measured using an Anti-Brownian ELectrokinetic
(ABEL) trap which provides precise multi-parameter spectroscopic measurements.
The ABEL trap also enables discrimination between FRETfluors attached to a
target (here: mRNA) and unbound FRETfluors, eliminating the need for washes or
removal of excess label by purification. We show single-molecule identification
of a set of 27 FRETfluors in a sample mixture using a subset of constructs
selected to minimize classification errors.Comment: 43 pages, 6 figures, 13 Supplementary figures, 3 Supplementary
tables, 5 Supplementary note
Serum proteins and paraproteins in women with silicone implants and connective tissue disease: a case–control study
Prior studies have suggested abnormalities of serum proteins, including paraproteins, in women with silicone implants but did not control for the presence of connective-tissue disease (CTD). This retrospective case–control study, performed in tertiary-care academic centers, assessed possible alterations of serum proteins, including paraproteins, in such a population. Seventy-four women with silicone implants who subsequently developed CTD, and 74 age-matched and CTD-matched women without silicone implants, were assessed in the primary study; other groups were used for additional comparisons. Routine serum protein determinations and high-sensitivity protein electrophoresis and immunofixation electrophoresis were performed for detection of paraproteins. Women with silicone implants, either with or without CTD, had significantly lower serum total protein and α1-globulin, α2-globulin, β-globulin, γ-globulin, and IgG levels compared with those without silicone implants. There was no significant difference, however, in the frequency of paraproteinemia between women with silicone implants and CTD (9.5%) and age-matched and CTD-matched women without silicone implants (5.4%) (odds ratio, 1.82; 95% confidence interval, 0.51–6.45). Paraprotein isotypes were similar in the two groups, and the clinical characteristics of the 13 women with paraproteinemia were comparable with an independent population of 10 women with silicone breast implants, CTD, and previously diagnosed monoclonal gammopathies. In summary, this first comprehensive study of serum proteins in women with silicone implants and CTD found no substantially increased risk of monoclonal gammopathy. Women with silicone implants, however, had unexpectedly low serum globulin and immunoglobulin levels, with or without the subsequent development of CTD. The causes and clinical implications of these findings require further investigation
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