Opening Reionization: Quantitative Morphology of the Epoch of Reionization and Its Connection to the Cosmic Density Field

We introduce a versatile and spatially resolved morphological characterisation of binary fields, rooted in the opening transform of mathematical morphology. We subsequently apply it to the thresholded ionization field in simulations of cosmic reionization and study the morphology of ionized regions. We find that an ionized volume element typically resides in an ionized region with radius $\sim8\,h^{-1}\mathrm{cMpc}$ at the midpoint of reionization ($z\approx7.5$) and follow the bubble size distribution even beyond the overlap phase. We find that percolation of the fully ionized component sets in when 25% of the universe is ionized and that the resulting infinite cluster incorporates all ionized regions above $\sim8\,h^{-1}\mathrm{cMpc}$. We also quantify the clustering of ionized regions of varying radius with respect to matter and on small scales detect the formation of superbubbles in the overlap phase. On large scales we quantify the bias values of the centres of ionized and neutral regions of different sizes and not only show that the largest ones at the high-point of reionization can reach $b\approx 30$, but also that early small ionized regions are positively correlated with matter and large neutral regions and late small ionized regions are heavily anti-biased with respect to matter, down to $b\lesssim-20$.Comment: 18 pages, 15 figure, as accepted for publication by MNRA

Earth-Mars transfers through Moon distant retrograde orbits

This paper focuses on trajectory design which is relevant for missions that would follow NASA’s Asteroid Redirect Mission (ARM) to further explore and utilise asteroids and eventually human Mars exploration. Assuming that a refueling gas station is present at a given Lunar Distant Retrograde Orbit (DRO), we analyse ways of departing from the Earth to Mars via that DRO. Thus, the analysis and results presented in this paper add a new cis-lunar departure orbit for Earth-Mars missions. Porkchop plots depicting the required C3 at launch, v1 at arrival, Time of Flight (TOF), and total ∆V for various DRO departure and Mars arrival dates are created and compared with results obtained for low ∆V LEO to Mars trajectories. The results show that low ∆V DRO to Mars transfers generally have lower ∆V and TOF than LEO to Mars maneuvers

Probing the high-z IGM with the hyperfine transition of 3^3He+^+

The hyperfine transition of $^3$He$^+$ at 3.5cm has been thought as a probe of the high-z IGM since it offers a unique insight into the evolution of the helium component of the gas, as well as potentially give an independent constraint on the 21cm signal from neutral hydrogen. In this paper, we use radiative transfer simulations of reionization driven by sources such as stars, X-ray binaries, accreting black holes and shock heated interstellar medium, and simulations of a high-z quasar to characterize the signal and analyze its prospects of detection. We find that the peak of the signal lies in the range 1-50 $\mu$K for both environments, but while around the quasar it is always in emission, in the case of cosmic reionization a brief period of absorption is expected. As the evolution of HeII is determined by stars, we find that it is not possible to distinguish reionization histories driven by more energetic sources. On the other hand, while a bright QSO produces a signal in 21cm that is very similar to the one from a large collection of galaxies, its signature in 3.5cm is very peculiar and could be a powerful probe to identify the presence of the QSO. We analyze the prospects of the signal's detectability using SKA1-mid as our reference telescope. We find that the noise power spectrum dominates over the power spectrum of the signal, although a modest S/N ratio can be obtained when the wavenumber bin width and the survey volume are sufficiently large.Comment: 10 pages, 13 figures, accepted for publication in MNRA

Impacts of fallow conditions, compost and silicate fertilizer on soil nematode community in salt–affected paddy rice fields in acid sulfate and alluvial soils in the Mekong Delta, Vietnam

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)Avoidance of intensive rice cultivation (IRC) and soil amendments are potential practices to enhance soil properties. There is only limited information on the effects of reduced IRC and its mixture with compost or silicate fertilizer (Si) on the soil nematode community in salt–affected soils. This study aimed to assess the shifts of soil nematode community by reducing a rice crop from triple rice system (RRR) to a double rice system and mixed with compost or Si in paddy fields in acid sulfate soil (ASS) and alluvial soil (AL) in the Mekong Delta, Vietnam. Field experiments were designed with four treatments in four replicates, including RRR and a proposed system of double–rice followed by a fallow (FRR) and with 3 Mg ha–1 crop−1 compost or 100 kg ha–1 crop−1 Si. Soils were collected at harvest after the 2 year experiment, reflecting the fifth and third consecutive rice crop in RRR and FRR system, respectively. Results showed that reduced IRC gave a significant reduction in abundance of plant–parasitic nematodes (PPN), dominated by Hirschmanniella and increased abundance bacterivorous nematodes when mixed to compost and silicate fertilizer in ASS. In addition, reduced IRC increased nematode biodiversity Hill’s indices and reduced herbivorous footprint in ASS. Proposed system having compost or Si had strongly increased in bacterivorous and omnivorous footprints. Particularly, reduced IRC mixture with Si increased abundance of Rhabdolaimus, Mesodorylaimus and Aquatides, metabolic footprints (structure footprint, bacterivorous, omnivorous and predator) and diversity Hill’s N1 index in ASS. Our results highlighted that reduced IRC was a beneficial practice for decreasing abundance of PPN in salt-affected soils and increasing abundance of FLN in ASS. IRC mixture with compost or Si had potential in structuring the nematode communities with increasing biodiversity, trophic structure, and metabolic footprintsPeer reviewedFinal Accepted Versio

Earth-Mars transfers through Moon distant retrograde orbits

This paper focuses on the trajectory design which is relevant for missions that would exploit the use of asteroid mining in stable cis-lunar orbits to facilitate deep space missions, specifically human Mars exploration. Assuming that a refueling “gas station” is present at a given lunar Distant Retrograde Orbit (DRO), ways of departing from the Earth to Mars via that DRO are analyzed. Thus, the analysis and results presented in this paper add a new cis-lunar departure orbit for Earth-Mars missions. Porkchop plots depicting the required C3 at launch, v∞ at arrival, Time of Flight (TOF), and total ΔV for various DRO departure and Mars arrival dates are created and compared with results obtained for low ΔV Low Earth Orbit (LEO) to Mars trajectories. The results show that propellant-optimal trajectories from LEO to Mars through a DRO have higher overall mission ΔV due to the additional stop at the DRO. However, they have lower Initial Mass in LEO (IMLEO) and thus lower gear ratio as well as lower TOF than direct LEO to Mars transfers. This results in a lower overall spacecraft dry mass that needs to be launched into space from Earth's surface

社団法人神緑会事業報告1

Archaeology, linguistics, and existing genetic studies indicate that Oceania was settled by two major waves of migration. The first migration took place approximately 40 thousand years ago and these migrants, Papuans, colonized much of Near Oceania. Approximately 3.5 thousand years ago, a second expansion of Austronesian-speakers arrived in Near Oceania and the descendants of these people spread to the far corners of the Pacific, colonizing Remote Oceania. To assess the female contribution of these two human expansions to modern populations and to investigate the potential impact of other migrations, we obtained 1,331 whole mitochondrial genome sequences from 34 populations spanning both Near and Remote Oceania. Our results quantify the magnitude of the Austronesian expansion and demonstrate the homogenizing effect of this expansion on almost all studied populations. With regards to Papuan influence, autochthonous haplogroups support the hypothesis of a long history in Near Oceania, with some lineages suggesting a time depth of 60 thousand years, and offer insight into historical interpopulation dynamics. Santa Cruz, a population located in Remote Oceania, is an anomaly with extreme frequencies of autochthonous haplogroups of Near Oceanian origin; simulations to investigate whether this might reflect a pre-Austronesian versus Austronesian settlement of the island failed to provide unequivocal support for either scenario

Chronic Hepatitis B Virus Infection and Rubella Susceptibility Among Obstetric Population in Metropolis Antenatal Centre Kano, Nigeria

It is well known that hepatitis B virus (HBV) infection is endemic in Nigeria. However, increased rubella susceptibility has been shown in patients from the Asian pacific region where chronic HBV infection is endemic. This study was carried out to assess the relationship between chronic HBV infection and rubella susceptibility in obstetric population aged 15–47 years attending Antenatal Clinic at Muhammad Abdullahi Wase Specialist Hospital Kano, Nigeria. From a total of 288 patients screened, 31 (10.76%) were reactive for HBsAg, meanwhile 50 (17.36%) were reactive to rubella IgM. Among the 31 infected patients 15 (48.39%) were from 20 – 24 years age bracket representing the most  susceptible age group while the infection rate was lowest (0.35%) in 45 – 49  age group (P = 0.00). The results of serological markers shows that HBsAg (+) was found in all 31 subjects (100%), anti HBs (+) 0 (0.00%), HBeAg (+) 3 (9.68%); anti HBe (+) and anti HBc (+) 24 (77.42%) respectively (P = 0.09). The study of liver enzymes activity among the HBV positive patients shows abnormal Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST) among HBsAg (+) and HBeAg (+) group. However, abnormal Alkaline phospatase (ALP) was found to be non-significantly different between HBsAg (+) and HBeAg (+) vsHBsAg (+) and HBeAg (-) groups (P=0.00). Moreover, obstetric histories such as abortion still birth and neonatal deaths among various age groups with respect to rubella was also studied, it implies that  out of the 50 reactive patients, 35(12.15%) had a previous abnormal obstetric history (P=0.02). In a comparative study conducted, it was observed that HBV carriers were (25.81%) susceptible to rubella as against (12.91%) observed in HBV free subjects (positive correlation). The study demonstrates strong associations between chronic HBV infection and rubella susceptibility among the studied population

Alarming rates of virological failure and HIV-1 drug resistance amongst adolescents living with perinatal HIV in both urban and rural settings: evidence from the EDCTP READY-study in Cameroon

Objectives: Adolescents living with perinatal HIV infection (ALPHI) experience persistently high mortality rates, particularly in resource-limited settings. It is therefore clinically important for us to understand the therapeutic response, acquired HIV drug resistance (HIVDR) and associated factors among ALPHI, according to geographical location. Methods: A study was conducted among consenting ALPHI in two urban and two rural health facilities in the Centre Region of Cameroon. World Health Organization (WHO) clinical staging, self-reported adherence, HIVDR early warning indicators (EWIs), immunological status (CD4 count) and plasma viral load (VL) were assessed. For those experiencing virological failure (VF, VL ≥ 1000 copies/mL), HIVDR testing was performed and interpreted using the Stanford HIV Drug Resistance Database v.8.9-1. Results: Of the 270 participants, most were on nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens (61.7% urban vs. 82.2% rural), and about one-third were poorly adherent (30.1% vs. 35.1%). Clinical failure rates (WHO-stage III/IV) in both settings were < 15%. In urban settings, the immunological failure (IF) rate (CD4  < 250 cells/μL) was 15.8%, statistically associated with late adolescence, female gender and poor adherence. The VF rate was 34.2%, statistically associated with poor adherence and NNRTI-based antiretroviral therapy. In the rural context, the IF rate was 26.9% and the VF rate was 52.7%, both statistically associated with advanced clinical stages. HIVDR rate was over 90% in both settings. EWIs were delayed drug pick-up, drug stock-outs and suboptimal viral suppression. Conclusions: Poor adherence, late adolescent age, female gender and advanced clinical staging worsen IF. The VF rate is high and consistent with the presence of HIVDR in both settings, driven by poor adherence, NNRTI-based regimen and advanced clinical staging

Involvement of promoter methylation in the regulation of Pregnane X receptor in colon cancer cells

<p>Abstract</p> <p>Background</p> <p>Pregnane X receptor (PXR) is a key transcription factor that regulates drug metabolizing enzymes such as cytochrome P450 (CYP) 3A4, and plays important roles in intestinal first-pass metabolism. Although there is a large inter-individual heterogeneity with intestinal CYP3A4 expression and activity, the mechanism driving these differences is not sufficiently explained by genetic variability of PXR or CYP3A4. We examined whether epigenetic mechanisms are involved in the regulation of PXR/CYP3A4 pathways in colon cancer cells.</p> <p>Methods</p> <p>mRNA levels of PXR, CYP3A4 and vitamin D receptor (VDR) were evaluated by quantitative real-time PCR on 6 colon cancer cell lines (Caco-2, HT29, HCT116, SW48, LS180, and LoVo). DNA methylation status was also examined by bisulfite sequencing of the 6 cell lines and 18 colorectal cancer tissue samples. DNA methylation was reversed by the treatment of these cell lines with 5-aza-2'-deoxycytidine (5-aza-dC).</p> <p>Results</p> <p>The 6 colon cancer cell lines were classified into two groups (high or low expression cells) based on the basal level of PXR/CYP3A4 mRNA. DNA methylation of the CpG-rich sequence of the <it>PXR </it>promoter was more densely detected in the low expression cells (Caco-2, HT29, HCT116, and SW48) than in the high expression cells (LS180 and LoVo). This methylation was reversed by treatment with 5-aza-dC, in association with re-expression of PXR and CYP3A4 mRNA, but not VDR mRNA. Therefore, PXR transcription was silenced by promoter methylation in the low expression cells, which most likely led to downregulation of CYP3A4 transactivation. Moreover, a lower level of <it>PXR </it>promoter methylation was observed in colorectal cancer tissues compared with adjacent normal mucosa, suggesting upregulation of the PXR/CYP3A4 mRNAs during carcinogenesis.</p> <p>Conclusions</p> <p><it>PXR </it>promoter methylation is involved in the regulation of intestinal PXR and CYP3A4 mRNA expression and might be associated with the inter-individual variability of the drug responses of colon cancer cells.</p