Hepatitis C virus (HCV) is a member of Flaviviridae family and one of the major causes of liver disease. There are about 175 million HCV infected patients worldwide that constitute 3% of world's population. The main route of HCV transmission is parental however 90% intravenous drug users are at highest risk. Standard interferon and ribavirin remained a gold standard of chronic HCV treatment having 38-43% sustained virological response rates. Currently the standard therapy for HCV is pegylated interferon (PEG-INF) with ribavirin. This therapy achieves 50% sustained virological response (SVR) for genotype 1 and 80% for genotype 2 & 3. As pegylated interferon is expensive, standard interferon is still the main therapy for HCV treatment in under developed countries. On the other hand, studies showed that pegylated IFN and RBV therapy has severe side effects like hematological complications. Herbal medicines (laccase, proanthocyandin, Rhodiola kirilowii) are also being in use as a natural and alternative way for treatment of HCV but there is not a single significant report documented yet. Best SVR indicators are genotype 3 and 2, < 0.2 million IU/mL pretreatment viral load, rapid virological response (RVR) rate and age <40 years. New therapeutic approaches are under study like interferon related systems, modified forms of ribavirin, internal ribosome entry site (HCV IRES) inhibitors, NS3 and NS5a inhibitors, novel immunomodulators and specifically targeted anti-viral therapy for hepatitis C compounds. More remedial therapies include caspase inhibitors, anti-fibrotic agents, antibody treatment and vaccines.

Lightning strokes are known to cause direct heating and ionization of the D region, some of which are detected via scattering of VLF transmitter signals and are known as Early VLF events. The disturbed ionosphere typically recovers in many tens of seconds. New experimental evidence is presented demonstrating that the scattering pattern and onset amplitude of Early VLF events are strongly related to both the magnitude and polarity of causative lightning peak current. Observations of Early VLF events at nine Stanford VLF receiver sites across the continental United States are combined with lightning geolocation data from the National Lightning Detection Network (NLDN). During January and March 2011, NLDN recorded 7769 intense lightning discharges with high peak currents (>100 kA) generating 1250 detected Early VLF events. We show that the size of the scattered field due to the ionospheric disturbance increases with the peak current intensity of the causative lightning discharge. The most intense peak currents of >+200 and <−250 kA disturb VLF transmitter signals as far as ∼400 km away from the lightning stroke. Early VLF event detection probability also increases rapidly with peak current intensity. On the other hand, the observed VLF amplitude change is not significantly dependent on the peak current intensity. Stroke polarity is also important, with positive strokes being ∼5 times more likely to generate Early VLF disturbances than negative strokes of the same intensity. Intense positive cloud‐to‐ground lightning discharges, especially when occurring over the sea, are also more likely to produce Early VLF events with long recovery (many minutes).

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The bismuth tri-iodide (BiI 3) is an inorganic compound. It is the result of the response of bismuth and iodine, which has inspired enthusiasm for subjective inorganic investigation. The topological indices are the numerical invariants of the molecular graph that portray its topology and are normally graph invariants. In 1975, Randic presented, in a bond-added substance, a topological index as a descriptor for portraying subatomic branching. In this paper, we investigate the precious stone structure of bismuth tri-iodide chain and sheet. Moreover, exact formulas of degree-based added-substance topological indices principally the first, second, and hyper Zagreb indices, the general Randic index, the geometric-arithmetic index, the fourth atom-bond connectivity index, and the fifth geometric arithmetic index of the subatomic graph of bismuth tri-iodide for both chain and sheet structures are determined.

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gate P dark is calculated by R dark /f g . Figure 3 shows the relationships between detection efficiency, dark count, and after-pulse probabilities. The SPAD is cooled to 253 K and its breakdown voltage V b is 267.8 V at this temperature. The excess voltage over V b is tuned between 1-2 V to achieve different detection efficiency. The dark count and after-pulse probabilities are 1.06 3 10 25 per gate and 4.3%, respectively, when the detection efficiency is 13.9%.We fixed the amplitude of gating pulse and tune the threshold of discriminator to investigate the trend of detection efficiency and dark count probability. As shown in Figure 4, both the detection efficiency and the dark count probability increase when lower threshold is used. This is reasonable because lower threshold can let more avalanche pulses to be discriminated as detection events. The threshold we used is much lower than the peak value of spike as shown in Figure 2 which indicates the spikes have been well suppressed.We further evaluate the distribution of after-pulse probability with OSC. The OSC is triggered by a 5 MHz clock signal synchronized with the optical pulse. Detection events with different time delay are recorded and accumulated in time domain. Figure 5 shows the result when the detection efficiency is set to 13.9%. We can see the distribution of after-pulse probability approximately follows exponential decay and a total after-pulse probability of 4.3% is obtained.The after-pulse probability actually can be further improved if a short dead time is applied after a detection event is captured [4] with slightly degradation on the detection efficiency. It should be emphasized that as we match the SPAD simply with voltage adjusted variode, complex and expensive components such as the delay line, band elimination filter, microwave devices, or another identical matched SPAD are not needed. All the components can be integrated within a package of 15 3 15 3 6 cm 3 . CONCLUSIONWe have demonstrated a balanced single photon avalanche detector with spike noise cancellation based on tunable variode. At 253 K, detection efficiency of 13.9% is obtained with 1.06 3 10 25 per gate dark count probability and 4.3% after-pulse probability under 100 MHz gating frequency.ABSTRACT: In this article, a dual-band coaxial-fed 2 3 2 rectangular U-Slot microstrip patch antenna array for multiple input multiple output applications, in 4G long term evolution (LTE) and WiMAX systems, is presented. The targeted frequency bands are: (1) LTE Band-1 at 2.