The effect of plant growth regulators on callus initiation in wormwood (Artemisia annua L.)

Studies were carried out in the Biotechnology laboratory of Plant Science Department of Ahmadu Bello University Zaria, Nigeria to study the effect of some plant growth regulators on the in vitro initiation of callus using the leaves of Chiyong variety of Artemisia annua. The explants were sterilized and incubated on Murashige and Skoog basal media augmented with varying concentrations ranging from 0.5 to 3.0 μm/l of Giberellic acid (GA3), Benzyle amino purine (BAP), Naphthyle acetic acid (NAA),2,4-Dichlrophynoxyacetic acid (2,4-D), Indole butyricacid (IBA) and Kinetin (Kin). The experiment was arranged in a completely randomized design with 2 replicates. Low BAP concentration of 0.5 μm/l and a high concentration of NAA of 3.0 μm/l as well as equal concentration of BAP of 1.0 μm/l and IBA of 1.0 μm/l had the least days (7days) to regeneration. For regeneration percent, equal low concentrations of BAP of 0.5 μm/l and NAA of 0.5 μm/l had the highest performance of 94%. However, no significant difference was observed between treatments with respect to vigor. Equal low concentrations of BAP (0.5 μm/l) and (0.5 μm/l) NAA and BAP(1.0 μm/l) combined with IBA(1.5 μm/l) had the highest height. Results of Analysis of Variance (ANOVA) indicated significant difference among the treatments compared with the control (P<0.05). Therefore, combined BAP and NAA treatment is an efficient protocol for callus initiation and proliferation. A combination of GA3 and BAP is suitable for shoot initiation from callus using cultures of A. annua.Keywords: Artemisia annua, in vitro, Nodal cuttings, growth regulator

Occurrence of multi-drug resistant Enterobacteriaceae in cultured Clarias gariepinus (African catfish) in Kano metropolis, Nigeria

Multi-drug resistant Enterobacteriaceae were isolated from cultured African catfish (Clarias gariepinus) from ten different fish farms located in Kano Metropolis, Nigeria using conventional methods of bacterial isolation, phenotypic characterization and antimicrobial susceptibility test. This study seeks to document the occurrence of Enterobacteriaceae isolates in cultured African catfish from ten registered fish farms, determine possible resistance to some antimicrobials and the fish safety for human consumption. Isolation and identification of microorganisms were carried out based on the standard procedures and antimicrobial susceptibility to 8 commonly used antimicrobials were conducted using the Kirby-Bauer disc diffusion method. Out of the 400 fish liver sampled, 370 (92.5%) were positive for Enterobacteriaceae isolates, these included 277 (69.25%) E. coli, 13 (3.25%) Salmonella spp, 36 (9%) Klebsiella spp, 21 (5.25%) Proteus spp and 23 (5.75%) Enterobacter spp. The prevalence of the multi-drug resistance was 97.5% for E. coli, 100% for Salmonella spp, 100% for Klebsiella spp, 90.5% for Proteus spp and 82.6% for Enterobacter spp. This study establishes the presence of some Enterobacteriaceae and the development of multi-drug resistance by these microorganisms. More studies like molecular characterization need to be carried out to determine the resistant genes in these organisms, also to assess antimicrobial use among fish farmers and the drug residue levels in the edible tissues of cultured African catfish in Kano Metropolis, Nigeria

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

Molecular diagnosis of urinary Mycobacterium tuberculosis among patients attending urology clinic in Aminu Kano Teaching Hospital, Kano, Nigeria

Background: Tuberculosis, a communicable disease with significant morbidity and mortality. It is still among the top killers of infectious diseases; Mycobacterium tuberculosis is a successful pathogen that has evolved several mechanisms to manipulate the host immune response. Objective of the study: The objective of this study was to determine the prevalence of urinary tuberculosis among patients attending urology clinic in Aminu Kano Teaching Hospital, Kano, Nigeria. Materials and Methods: A prospective cross-sectional laboratory based study that involved the use of questionnaire and consent/assent form prior to sample collection. Xpert MTB/Rif assay was used to analyze the urine samples. Results: The results of this study shows that, out of 71 samples analyzed along with positive control (H37RV) and molecular grade water was used as negative control. The results showed that, 2 (2.8 %) were from urine samples. Data generated were analyzed using descriptive statistics and results were presented in tables and charts. Conclusion: The study confirmed the presence of urinary tuberculosis in the study area, with prevalence of 2.8%. The pattern of tuberculosis was susceptible Mycobacterium tuberculosis. Therefore, there is need to introduce a routine screening of urinary tuberculosis among patients presenting sign and symptoms of urinary tract infection using Gene Xpert. This will be achieved through the engagement and enlightenment of the clinicians, strengthening the laboratory capacity for diagnosis and make the services available and accessible to the patients who need them. Keywords: Mycobacterium tuberculosis; Extra-Pulmonary Tuberculosis; Prevalence and Gene Xpert

Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018

Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations.Peer reviewe

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