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1.
Nature ; 626(7999): 505-511, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356069

RESUMO

Non-Abelian topological order is a coveted state of matter with remarkable properties, including quasiparticles that can remember the sequence in which they are exchanged1-4. These anyonic excitations are promising building blocks of fault-tolerant quantum computers5,6. However, despite extensive efforts, non-Abelian topological order and its excitations have remained elusive, unlike the simpler quasiparticles or defects in Abelian topological order. Here we present the realization of non-Abelian topological order in the wavefunction prepared in a quantum processor and demonstrate control of its anyons. Using an adaptive circuit on Quantinuum's H2 trapped-ion quantum processor, we create the ground-state wavefunction of D4 topological order on a kagome lattice of 27 qubits, with fidelity per site exceeding 98.4 per cent. By creating and moving anyons along Borromean rings in spacetime, anyon interferometry detects an intrinsically non-Abelian braiding process. Furthermore, tunnelling non-Abelions around a torus creates all 22 ground states, as well as an excited state with a single anyon-a peculiar feature of non-Abelian topological order. This work illustrates the counterintuitive nature of non-Abelions and enables their study in quantum devices.

2.
Pak J Pharm Sci ; 34(2): 507-512, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34275823

RESUMO

Myrsine africana L. a commonly consumed medicinal plant grows in forest of mountains region located at North East of Pakistan. In current study, the fruit extracts were chemically characterized and their bioactivities were determined. Higher quantity of total phenols, total flavonoids and tannins were obtained from methanolic fruit extracts. The HPLC analysis provided higher level of quercetin followed by rutin and p-coumaric acid. Whereas the GC-MS quantification had given significant level of ten saturated and unsaturated fatty acids and some of them were not reported earlier. In vitro study, lower cytotoxic behavior of fruit extracts but higher antioxidant values as well as higher zone of inhibition versus S. aureus, E. coli, K. pneumonia and B. subtilis and Mycobacterium tuberculosis were observed. The organic compounds found in fruit extracts of M. africana correlated well with its used in ethno medicines.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Frutas , Myrsine , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Bacillus subtilis/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/química , Escherichia coli/efeitos dos fármacos , Ácidos Graxos , Ácidos Graxos Insaturados , Cromatografia Gasosa-Espectrometria de Massas , Klebsiella pneumoniae/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Quercetina/química , Rutina/química , Staphylococcus aureus/efeitos dos fármacos
3.
PLoS One ; 15(12): e0244595, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33347519

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0239008.].

4.
PLoS One ; 15(9): e0239008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956410

RESUMO

This paper presents analysis, design and experimentation of a high voltage DC power supply (HVDCPS) with power factor correction based on LLC resonant converter. For power factor correction improvement, the proposed topology has an input rectifier with two filter capacitors, two inductors with a bus capacitor (Cbus) and a resonant tank. To prevent the reverse current flow towards the source diodes (D9 & D10) are employed. A couple of power switches are inserted in a single leg that makes a half-bridge network. To form an LLC resonance circuit, a capacitor and two inductors are connected to the primary winding of the high voltage transformer (HVT). To rectify the high frequency and high voltage, a full-bridge rectifier is inserted to secondary side of high voltage transformer (HVT). The secondary diodes always get on and off under zero current switching (ZCS) due to discontinuous conduction mode of proposed topology. It is found that due to power factor correction, less cost, lower losses and smaller size, the proposed topology achieves several major improvements over the conventional high voltage power supply. To obtain zero voltage switching (ZVS) the converter operate in a narrow frequency range. The output voltage can be varied or regulate through pulse width modulation of power switches. Due to ZVS and ZCS, the proposed topology has minimum switching losses and therefore higher efficiency. To verify the feasibility of the proposed topology a prototype is being implemented and verified by simulation & experimental results for 1.5KV prototype of the proposed topology. The results make sure the achievement, good efficiency and successful operation of the proposed topology.


Assuntos
Fontes de Energia Elétrica/tendências , Desenho de Equipamento/instrumentação , Desenho de Equipamento/métodos , Simulação por Computador , Capacitância Elétrica
5.
Cureus ; 12(6): e8483, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32642387

RESUMO

Chorea is an abnormal, nonrhythmic, and purposeless movement of limbs. There is a long list of diseases responsible for chorea; long-standing hyperglycemia can sometimes result in it, which typically manifests on one side of the body. MRI brain is an added diagnostic tool, which commonly shows hyperintense basal ganglia lesion on T1-weighted images. Chorea in the context of hyperglycemia is a reversible and infrequent occurrence, best managed with insulin and haloperidol combination therapy. Here, we discuss a patient with hyperglycemic-hemichorea, whose symptoms resolved completely within two months of taking insulin and haloperidol.

6.
South Med J ; 102(12): 1246-52, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20016433

RESUMO

Narcolepsy is a serious neurological condition in which patients are overcome by persistent, excessive feelings of fatigue and drowsiness. In addition to chronic fatigue, patients with narcolepsy often succumb to intermittent, uncontrollable periods where they abruptly fall asleep during waking hours. In addition to episodic bouts of daytime sleeping, narcoleptics also exhibit cataplexy, sleep paralysis, and hypnagogic and hypnopompic hallucinations. Unfortunately, many individuals with narcolepsy remain undiagnosed and therefore, untreated, posing a risk to themselves and those around them. There is currently no cure for this lifelong disease. Nonetheless, narcolepsy can be effectively managed with medications, lifestyle changes, and the peripheral support of individuals such as family members, coworkers, and other casual relations.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/líquido cefalorraquidiano , Narcolepsia/diagnóstico , Narcolepsia/terapia , Neuropeptídeos/líquido cefalorraquidiano , Atenção Primária à Saúde , Compostos Benzidrílicos/uso terapêutico , Biomarcadores/líquido cefalorraquidiano , Cataplexia/etiologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Tomada de Decisões , Diagnóstico Diferencial , Aprovação de Drogas , Alucinações/etiologia , Humanos , Estilo de Vida , Metilfenidato/uso terapêutico , Modafinila , Narcolepsia/líquido cefalorraquidiano , Narcolepsia/complicações , Narcolepsia/tratamento farmacológico , Narcolepsia/etiologia , Narcolepsia/fisiopatologia , Orexinas , Médicos de Família , Polissonografia , Qualidade de Vida , Respiração , Fatores de Risco , Paralisia do Sono/etiologia , Fases do Sono , Oxibato de Sódio , Estados Unidos , United States Food and Drug Administration
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