34 research outputs found
Effects of shisha smoke inhalation on some long-term memory forms in adult male mice
Background: Shisha is a flavoured tobacco designed to be smoked in a water-pipe, but it effects on long-term memory has not been fully explored. This study was undertaken to evaluate the effect of Shisha smoke inhalation on some long-term memory models in adult male BALB/c mice.
Methods: Twenty male mice were divided into 4 groups of five mice each. Group I (control): fresh air; group II: exposed to bonged Shisha; group III: exposed to unbonged Shisha; group IV: exposed to activated charcoal smoke only. Each group was exposed for thirty minutes daily for seven weeks. Long-term memory was assessed using elevated plus maze (EPM), novel object recognition test (NORT) and Barnes maze (BM).
Results: There was statistically significant decrease (P<0.05) in novel object recognition in bonged Shisha group when compared with the control. There was statistically significant increase (P<0.05) in spatial learning and memory in bonged Shisha group when compared with control. There was statistically significant decrease (P<0.05) in acetylcholinesterase activity in bonged Shisha group when compared with control, but there was no statistically significant difference in anxiety related spatial memory in elevated plus maze when compared with the control. There was also increased in necrosis of hippocampal cells in bonged Shisha group and slight necrosis in unbonged and activated charcoal smoke when compared to control mice.
Conclusion: The outcomes of this study suggest that bonged Shisha smoke is neurotoxic to the brain because of combined effect of various toxicants emanating from different Shisha smoke constituents used in the set-up
Keywords: Shisha, Memory, Hippocampus, Acetylcholinesteras
Seroprevalence of Hepatitis B Virus and Human Immunodeficiency Virus infection among students in Ahmadu Bello University, Zaria, Nigeria
Hepatitis B virus (HBV) and Human Immunodeficiency Virus (HIV) are endemic in sub-Saharan Africa. Evidence on HBV co-infection rates with HIV infection among individuals remains conflicting. The study was conducted to determine the seroprevalence of HBV and HIV infections and the possible potential risk factors among students of Ahmadu Bello University (ABU), Zaria, Nigeria. Blood samples were collected from 600 consenting consecutive students aged between 16 and 40 years old at the University Health Services, ABU, Zaria. The sera were screened for HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc using diagnostic kits and for Human Immunodeficiency Virus using DetermineTMHIV-1/2 kits. Reactive sera for HBsAg were further confirmed using ELISA kits. For HBsAg, 9.2% (55/600) tested positive among which, none had detectable anti-HBs antibodies, indicating recent infection. About 7.3%, 36.4% and 94.5% were positive for HBeAg, anti-HBe and anti-HBc respectively. Seroprevalence of HIV infection was 2.8% (17/600). One (0.2%) of the student was infected with both HBV and HIV. There was a significant association between age group (p=0.016), gender (p=0.049), family history of HBV infection (p=0.000), and seroprevalence of HBsAg. While for HIV, only menial jobs (p = 0.001) was significantly associated with the infection. The results showed close contact among family members to be a predisposing factor to these viral infections. A total of 314 students were ignorant of HBV and four of them were infectious. The seroprevalence of HBsAg obtained in this study indicates high endemicity according to WHO classification. However, seroprevalence of HIV and its co-infection rate with HBV were very low. This was encouraging and it indicates that the campaign on HIV is yielding the desired result. Therefore similar campaign should be extended to Hepatitis B.Keywords: Seroprevalence; HIV; HBsAg; Serological markers; Students; Nigeri
DUAL MODALITY TOMOGRAPHY SYSTEM USING OPTICAL AND ELECTRODYNAMIC SENSORS FOR TOMOGRAPHIC IMAGING SOLID FLOW
Avaliação da eficiência da desinfecção de teteiras e dos tetos no processo de ordenha mecânica de vacas
Aspectos microscópicos da interação feijoeiro-Colletotrichum lindemuthianum mediados pelo silício
A antracnose, causada pelo fungo Colletotrichum lindemuthianum, é uma das doenças mais destrutivas que afetam a cultura do feijoeiro. Com o objetivo de encontrar alternativas para o controle dessa doença, o presente trabalho investigou, em nível microscópico, o efeito do silício (Si) na resistência do feijoeiro à infecção por C. lindemuthianum. Plantas de feijoeiro (cv. Pérola) foram cultivadas em solução nutritiva contendo 0 (-Si) ou 2 mM (+Si) de Si e inoculadas no estádio de crescimento V4 com uma suspensão de conídios de C. lindemuthianum. A severidade da antracnose decresceu cerca de 52% nas folhas das plantas supridas com Si (4,4%) em relação às folhas das plantas não supridas (8,5%). Observações de folhas de feijoeiro das plantas não supridas com Si no microscópio eletrônico de varredura revelaram alterações morfológicas nas nervuras em contraste com as folhas de plantas supridas com Si. Utilizando-se a microanálise de raios-X, verificou-se maior concentração dos minerais enxofre, potássio e Si nas folhas das plantas supridas com Si. Em conclusão, o suprimento de Si em plantas de feijoeiro foi importante para reduzir os sintomas da antracnose
Erratum: "A Gravitational-wave Measurement of the Hubble Constant Following the Second Observing Run of Advanced LIGO and Virgo" (2021, ApJ, 909, 218)
[no abstract available
All-sky search for long-duration gravitational wave transients with initial LIGO
We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society
All-sky search for long-duration gravitational wave transients with initial LIGO
We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society
Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model
We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO's second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h095%=3.47×10-25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering. © 2019 American Physical Society
Search for Tensor, Vector, and Scalar Polarizations in the Stochastic Gravitational-Wave Background
The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically polarized gravitational waves. We find no evidence for a background of any polarization, and place the first direct bounds on the contributions of vector and scalar polarizations to the stochastic background. Under log-uniform priors for the energy in each polarization, we limit the energy densities of tensor, vector, and scalar modes at 95% credibility to Ω0T<5.58×10-8, Ω0V<6.35×10-8, and Ω0S<1.08×10-7 at a reference frequency f0=25 Hz. © 2018 American Physical Society