Ultrafast switching of photonic entanglement

To deploy and operate a quantum network which utilizes existing telecommunications infrastructure, it is necessary to be able to route entangled photons at high speeds, with minimal loss and signal-band noise, and---most importantly---without disturbing the photons' quantum state. Here we present a switch which fulfills these requirements and characterize its performance at the single photon level; it exhibits a 200-ps switching window, a 120:1 contrast ratio, 1.5 dB loss, and induces no measurable degradation in the switched photons' entangled-state fidelity (< 0.002). Furthermore, because this type of switch couples the temporal and spatial degrees of freedom, it provides an important new tool with which to encode multiple-qubit states in a single photon. As a proof-of-principle demonstration of this capability, we demultiplex a single quantum channel from a dual-channel, time-division-multiplexed entangled photon stream, effectively performing a controlled-bit-flip on a two-qubit subspace of a five-qubit, two-photon state

Pharmacological Screening of Polyherbal Formulation for Diabetic Associated Hyperlipidemia

&nbsp; Plant parts such as seeds, berries, roots, leaves, bark, or flowers can be used medicinally. This practise is known as herbal medicine, botanical medicine, or phytomedicine. Outside of mainstream treatment, herbalists have long used herbalism for conventional medicine. Grewia subinaequalisDC in the family Tiliaceae, only one genus,&nbsp;Grewia, yields edible fruit. Saccharum officinarum is a species of grass belonging to the genus Saccharum that is characterised by its robust growth and size. Neisosperma oppositifolium is a tree that typically exhibits a height range of 6 to 25 metres, although it has been observed to vary from as low as 2.5 metres to extraordinarily high heights of 45 metres, and in rare cases, even up to 60 metres. The presence of moisture in crude pharmaceuticals is an unavoidable factor that should be minimised to the greatest extent possible9,10. The process of drying significantly influences both the quality and purity of the material. &nbsp

Interaction-Free All-Optical Switching via Quantum-Zeno Effect

We propose a novel interaction-free scheme for all-optical switching which does not rely on the physical coupling between signal and control waves. The interaction-free nature of the scheme allows it to overcome the fundamental photon-loss limit imposed by the signal-pump coupling. The same phenomenon protects photonic-signal states from decoherence, making devices based on this scheme suitable for quantum applications. Focusing on $\chi^{(2)}$ waveguides, we provide device designs for traveling-wave and Fabry-Perot switches. In both designs, the performance is optimal when the signal switching is induced by coherent dynamical evolution. In contrast, when the switching is induced by a rapid dissipation channel, it is less efficient.Comment: 14 pages, 14 figures, submitted to Physical Review

All-optical switching of photonic entanglement

Future quantum optical networks will require the ability to route entangled photons at high speeds, with minimal loss and added in-band noise, and---most importantly---without disturbing the photons' quantum state. Here we present an all-optical switch which fulfills these requirements and characterize its performance at the single photon level. It exhibits a 200-ps switching window, 120:1 contrast, 1.5-dB loss, and induces no measurable degradation in the switched photons' entangled-state fidelity (< 0.002). As a proof-of-principle demonstration of its capability, we use the switch to demultiplex a single quantum channel from a dual-channel, time-division-multiplexed entangled photon stream. Furthermore, because this type of switch couples the temporal and spatial degrees of freedom, it provides an important new tool with which to encode multiple-qubit quantum states on a single photon

Heralding Single Photons Without Spectral Factorability

Recent efforts to produce single photons via heralding have relied on creating spectrally factorable two-photon states in order to achieve both high purity and high production rate. Through a careful multimode analysis, we find, however, that spectral factorability is not necessary. Utilizing single-mode detection, a similar or better performance can be achieved with non-factorable states. This conclusion rides on the fact that even when using a broadband filter, a single-mode measurement can still be realized, as long as the coherence time of the triggering photons exceeds the measurement window of the on/off detector.Comment: 7 pages, 5 figure

Anti-inflammatory and analgesic effects of coral reef associated gastropod, Trochus tentorium from Tuticorin coastal waters, Southeastern India

The aim of this work was to investigate extensively, the biomedical potential of the mollusc Trochus tentorium which are abundantly associated with coral reef of the Tuticorin coastal water. The 100% acetone fraction of the gastropod tested for its analgesic effect on Swiss mice model and anti-inflammatory activity on albino rat showed promising results. T. tentorium at the concentration of 25 and 50 mg/kg (p.o) showed significant decrease in the paw thickness (41.15 and 73.6%, respectively) at the 5th hour of the experiment. The 100% column-purified fraction of the T. tentorium (200 mg/kg p.o) exhibited significant (p &lt; 0.001) inhibition of 79.22% against acetic acid induced abdominal constrictions. The dose of 25 mg/kg showed the inhibitions in the writhings of 67.86% (p&lt;0.001) of animals when compared to the standard (diclofenac sodium), and 56.83% (50 mg/kg) inhibition was observed. These facts suggest that T. tentorium is a potential source for anti-inflammatory and analgesic compounds.Key words: Analgesic activity, anti-inflammatory activity, mollusc, southeastern India

Erasing Quantum Distinguishability via Single-Mode Filtering

Erasing quantum-mechanical distinguishability is of fundamental interest and also of practical importance, particularly in subject areas related to quantum information processing. We demonstrate a method applicable to optical systems in which single-mode filtering is used with only linear optical instruments to achieve quantum indistinguishability. Through "heralded" Hong-Ou-Mandel interference experiments we measure and quantify the improvement of indistinguishability between single photons generated via spontaneous four-wave mixing in optical fibers. The experimental results are in excellent agreement with predictions of a quantum-multimode theory we develop for such systems, without the need for any fitting parameter.Comment: 5 pages, 5 figure

Bactericidal Efficacy Of Antibiotic Combinations Against Enterococcus Faecalis – An In Vitro Study

Endodontics plays a major role in the eradication of pulpal inflammation, the primary goal includes the treatment of apical periodontitis and maintaining the pulpal health. An immature necrotic tooth poses various challenges in the management of pulpal necrosis which traditionally aims at the formation of calcific barrier that aid in the obturation. The prolonged duration of the procedure with multiple review appointments, and the risk of cervical fracture have posed a challenge in the conventional apexification procedures1. Regenerative endodontics is a biological based procedure designed to replace damaged structures such as dentin, root structures, and cells of the pulp-dentin complex. The evolution of the method of biologically replacing dental tissues by regeneration has overcome the challenges by increasing the root length and thickness of the root canal walls, inducing apexogenesis 2. The outcomes of regenerative procedures rely on the complete elimination of bacteria, facilitation of root development, and closure of sinus tracts3. The infection of the root canal system is polymicrobial, consisting of predominantly facultative anaerobes and anaerobic bacteria. The existence of bacterial species results in the persistence of apical periodontitis and inflammation4. The virulence of the bacteria on causing disease and tissue damage is proportionate to the type and the numbers of bacteria present5. The microbial flora in failed endodontic teeth normally include varied microorganisms of which Enterococcus faecalis is the most prevalent and highly resistant to intracanal medicaments6. It is an established fact that regeneration of the pulpal tissue of an infected immature tooth with open apex and apical periodontitis was considered to be impossible due to the presence of various microorganisms. Local antibiotics application has been widely used in the eradication of intracanal infection, hence the systemic routes of administration have been greatly reduced 7. To encounter the diverse flora in the root canal system, combinations of antibiotics are used known as the TRIPLE ANTIBIOTIC PASTE which comprises of combination of Ciprofloxacin, Metronidazole and Minocycline 8. The synergy of antibiotics used in the triple antibiotic paste is used to efficiently combat the polymicrobial environment in the infected root dentin 9. Minocycline is known for its broad-spectrum activity but has the disadvantage of discoloration of teeth which has led to the necessity of finding an alternative antibiotic. In this study in the triple antibiotic combination minocycline is replaced with clindamycin. This study aimed at comparing and evaluating the antibacterial efficacy of double or triple antibiotic combinations used as intracanal medicament. A standard strain of Enterococcus faecalis is used as a indicator organism to test the efficacy. The primary objective was to compare the efficacy of clindamycin over minocycline in combination with other antibiotic

Qualitative Analysis and Antibacterial Activity of Pelargonium graveolenL’Herit

Medicinal plants are an important source of phytochemicals that offer traditional medicinal treatment of various ailments and one of the plants is Pelargonium Graveolens which was grown in Hyderabad province. The preliminary screening of their aerial leaves showed best results the presence of different phytochemical like alkaloids, flavonoids, glycosides, phenol, sterol and lignin found in Methanolic and Ethyl acetate extract. However chloroform extract revealed the absence of alkaloids and sterols, where as in Water extract flavonoids, phenol, sterol and lignin. The best resulted extracts from preliminary screening test were subjected to Antimicrobial studies like some on gram positive and gram negative bacterial strains which exhibited a significant effect.  The both ethyl acetate  and methanolic extracts were showed the similar zone of inhibition on gram positive bacteria (S.aurea and B.Subtilus) whereas  ethyl acetate  extract positive inhibition on k.pneumonia  when compare to methanolic  extract  and which are more active suppression on gram negative  bacterial (E.coli) in comparison with the standard antibiotic.