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Floristic diversity is the set of plant species of an ecosystem or a given environment. Recruits are species regenerated after a disturbance in an environment. In this study it is a natural regeneration different from the artificial regeneration. The main objective of this study is to assess the level of natural regeneration under the artificial plantations. The strip sounding method is used over approximately two (2) hectares per type of plantation. Parameters measured are the abundance of recruits, the specific richness, the abundance of genera and families and the diameters of the stems. The floristic diversity was assessed through five indices. These are the Shannon indices, Simpson indices, Hill indices, regularity indices and generic diversity indices. . The results of the inventory show that the abundance of recruits is significantly different in the plantations and the surrounding forest. Species richness varies by type of plantation. Almost all of the three types of vegetation in the plantations have a Shannon index significantly greater than 1 and testifies to the very high diversity. The 1-Hill difference reached the value 0.97, 0.94 and 0.9 which values very close to 1. The regularity index shows that the taxa of plant communities of the recruits are not regularly distributed and have a low taxonomic richness. The lowest value of the generic diversity indices is 1.07. This shows that generic diversity is low in the three plantations. The floristic affinity between the 3 plantations is greater than 50%. According to Sørensen, these results demonstrate that the three plantations have the same floristic composition and constitute the same biological unit.

Masteroppgave i engelsk, Høgskulen på Vestlandet, campus Bergen MGUEN550

To overcome the multiple challenges currently faced by agriculture, such as climate change and soil deterioration, more efficient plant breeding strategies are required. Genomic selection (GS) is crucial for the genetic improvement of quantitative traits, as it can increase selection intensity, shorten the generation interval, and improve selection accuracy for traits that are difficult to phenotype. Tropical perennial crops and plantation trees are of major economic importance and have consequently been the subject of many GS articles. In this review, we discuss the factors that affect GS accuracy (statistical models, linkage disequilibrium, information concerning markers, relatedness between training and target populations, the size of the training population, and trait heritability) and the genetic gain expected in these species. The impact of GS will be particularly strong in tropical perennial crops and plantation trees as they have long breeding cycles and constrained selection intensity. Future GS prospects are also discussed. High-throughput phenotyping will allow constructing of large training populations and implementing of phenomic selection. Optimized modeling is needed for longitudinal traits and multi-environment trials. The use of multi-omics, haploblocks, and structural variants will enable going beyond single-locus genotype data. Innovative statistical approaches, like artificial neural networks, are expected to efficiently handle the increasing amounts of heterogeneous multi-scale data. Targeted recombinations on sites identified from profiles of marker effects have the potential to further increase genetic gain. GS can also aid re-domestication and introgression breeding. Finally, GS consortia will play an important role in making the best of these opportunities.

Genomic selection (GS) is the most effective method of marker-assisted selection for the genetic improvement of complex traits in plants and animals. Optimization approaches could be used in conjunction with GS to further increase its efficiency and to limit inbreeding, which can increase faster with GS. Mate selection (MS) typically uses a metaheuristic optimization algorithm, simulated annealing, to optimize the selection of individuals and their matings. However, in species with long breeding cycles, this cannot be studied empirically. Here, we investigated this aspect with forward genetic simulations on a high-performance computing cluster and massively parallel computing, considering the oil palm hybrid breeding example. We compared MS and simple methods of inbreeding management (limitation of the number of individuals selected per family, prohibition of self-fertilization and combination of these two methods), in terms of parental inbreeding and genetic progress over four generations of genomic selection and phenotypic selection. The results showed that, compared to the conventional method without optimization, MS could lead to significant decreases in inbreeding and increases in annual genetic progress, with the magnitude of the effect depending on MS parameters and breeding scenarios. The optimal solution retained by MS differed by five breeding characteristics from the conventional solution: selected individuals covering a broader range of genetic values, fewer individuals selected per full-sib family, decreased percentage of selfings, selfings preferentially made on the best individuals and unbalanced number of crosses among selected individuals, with the better an individual, the higher the number of times he is mated. Stronger slowing-down in inbreeding could be achieved with other methods but they were associated with a decreased genetic progress. We recommend that breeders use MS, with preliminary analyses to identify the proper parameters to reach the goals of the breeding program in terms of inbreeding and genetic gain.Author summaryOil palm is a tropical perennial plant and the world main source of vegetable fats. Oil palm breeding requires the estimation of the additive genetic value of the selection candidates to identify the best hybrid crosses, that will be released as commercial varieties. Genomic selection (GS) is a marker-assisted selection method that has the potential of boosting the rate of genetic progress for quantitative traits. However, GS could also be used in conjunction with approaches to optimize selection and mating, in order to maximize genetic progress while limiting inbreeding, which can increase faster with GS and can have negative consequences (inbreeding depression detrimental for seed production, loss of favorable alleles). This study compared several strategies to reach this goal. In particular, we considered mate selection (MS), a method that uses an algorithm optimizing the selection of individuals and their crosses. Our results showed that MS reduced inbreeding in parental populations and increased annual genetic progress. The originality of this work resides in the fact that, despite the high computational burden of MS, we applied it in a large simulated dataset and showed its efficiency in the context of genomic and conventional selection. Also, this is the first study to characterize, in terms of breeding rules, the optimized solution (i.e. the set of selected individuals and their mating design) retained by MS.

Infection with the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), may cause viral pneumonia and acute respiratory distress syndrome (ARDS). Treatment of ARDS often requires mechanical ventilation and may take weeks for resolution. In areas with a large outbreaks, there may be shortages of ventilators available. While rudimentary methods for ventilator splitting have been described, given the range of independent ventilatory settings required for each patient, this solution is suboptimal. Here, we describe a device that can split a ventilator among up to four patients while allowing for individualized settings. The device has been validated in vitro and in vivo .

We introduce the Australia Telescope Compact Array (ATCA) rapid-response mode by presenting the first successful trigger on the short-duration gamma-ray burst (GRB) 181123B. Early-time radio observations of short GRBs may provide vital insights into the radio afterglow properties of Advanced LIGO- and Virgo-detected gravitational wave events, which will in turn inform follow-up strategies to search for counterparts within their large positional uncertainties. The ATCA was on target within 12.6 hr post-burst, when the source had risen above the horizon. While no radio afterglow was detected during the 8.3 hr observation, we obtained force-fitted flux densities of $7 \pm 12$ and $15 \pm 11~\mu$Jy at 5.5 and 9 GHz, respectively. Afterglow modelling of GRB 181123B showed that the addition of the ATCA force-fitted radio flux densities to the Swift X-ray Telescope detections provided more stringent constraints on the fraction of thermal energy in the electrons (log$\epsilon_e = -0.75^{+0.39}_{-0.40}$ rather than log$\epsilon_e = -1.13^{+0.82}_{-1.2}$ derived without the inclusion of the ATCA values), which is consistent with the range of typical $\epsilon_e$ derived from GRB afterglow modelling. This allowed us to predict that the forward shock may have peaked in the radio band $\sim10$ days post-burst, producing detectable radio emission $\gtrsim3-4$ days post-burst. Overall, we demonstrate the potential for extremely rapid radio follow-up of transients and the importance of triggered radio observations for constraining GRB blast wave properties, regardless of whether there is a detection, via the inclusion of force-fitted radio flux densities in afterglow modelling efforts., Comment: 15 pages, 7 figures, accepted for publication in MNRAS

In the perspective of investigating genomic selection (GS) among Musa genotypes in West and Central Africa, banana accessions were phenotyped under natural drought stress in Benin and genotyped using genotyping by sequencing. Sixty-one (61) accessions grouped into three major genomic groups AAA, AAB and ABB and those without genomic affiliation information were used. Variation within the population was determined by phenotypic variables while population structure and clustering analysis were carried out to understand the genetic diversity at the molecular level. Among the genomic groups evaluated, the group AAB showed the best performance for fruit weight at maturity, (3.41 ± 1.99 kg) and for plant height (198.46 ± 12.66 cm). At the accession level, HD 117 S1 and NIA 27 showed the best plant height (263.16 ± 20.98 cm) and the best fruit weight at maturity (9.43 ± 0.0 kg) respectively. Phenotypic data did not reveal clear genetic diversity among accessions; however, the genetic diversity was conspicuous at the molecular level using 5000 markers. The affiliations of local accessions in genomic groups were determined for the first time based on the phenotypic and molecular data obtained in this study. The knowledge generated allows the possibility to apply GS in banana.

This paper outlines a very longue durée history of three of North China's most important cereal crops: broomcorn millet, foxtail millet, and wheat. It illustrates their place within broader social-environmental formations, highlighting the various biological and cultural factors that enabled the spread of these crops, as well as the ways in which these crops and the patterns in which they are grown influenced North China's economic and social history. We demonstrate that a very long-run approach raises new questions and clarifies the significance of particular transitions. The article charts the transition from broomcorn to foxtail millet cultivation in the late Neolithic, and then the rise of wheat in the first millennium ce. It shows that efforts to spread winter wheat met some resistance from farming communities, and presents the hypothesis that the different processing technologies for wheat and millet may have played a role in the divergence of different Eurasian societies. Finally the article considers the debate over the spread of multiple-cropping systems to North China.

A study was conducted to assess genotype x environment interaction and also to determine stability of okra (Abelmoschus esculentus L. Moench) genotypes for nine traits in Cameroon. Eight okra genotypes (including five parents of Cameroon and three exotics) were evaluated across three different locations (Dibang, Yagoua and Yaounde) using a randomized complete block design (RCBD) with three replications. Each plot consisted of three rows of six plants each. Genotype x environment interaction has been evaluated using SAS Software. There was considerable variation for all traits studied among both genotypes and environments. Five different methods of stability analysis have been used for the comparison of the genotypes and also to determine the most suitable stability parameter of okra. The stability in relation to the characters is independent of the genotypes. A total correspondence (r=1) exist between the general mean and the Pi performance for characters such as 50 % flowering and the fruit peduncle length. For, the procedure of Lin and Binns appeared to be more of a genotype performance measure, rather than a stability measure. The Wricke’s and Shukla’s procedures of stability statistic showed the highest significant positive correlation (P

Objective: To compare laparoscopic Keyhole repair with the modified Sugarbaker repair in a nonrandomized case-controlled prospective study of consecutive patients with parastomal hernia. Background: Two reviews of uncontrolled studies concluded that the Sugarbaker repair is superior to the Keyhole repair. The present study challenges the claim. Materials and Methods: In two time periods, 135 patients with a parastomal hernia were repaired with the Keyhole technique (74 patients, using a two-layer mesh of polypropylene and polytetrafluoroethylene [ePTFE] with a self-cut slit, 1997-2009) or the Sugarbaker technique (61 patients, using a coated polypropylene mesh, 2009-2015). The patients in the two groups matched with regard to clinical profile, colostomy or ileostomy hernia, previous repairs, size of fascial defect, and simultaneous repair of a concurrent incisional hernia. Observation time was defined as time to recurrence, stoma resiting, mesh removal, death, or last nonevent visit. Results: In-hospital morbidity did not differ with two fatalities in each group. Seventy and fifty-eight patients after Keyhole and Sugarbaker repair, respectively, were available for follow-up. Two patients after Sugarbaker repair were lost to follow-up. After a median follow-up of 57 months, five recurrences were diagnosed in the Keyhole group (7%). In the Sugarbaker group, six recurrences (10%) were observed after a median follow-up of 11 months. Late mesh-related morbidity occurred in 6 and 6 patients after Keyhole (8%) and Sugarbaker repair (10%), respectively. Conclusion: The present study indicates that the Keyhole repair, using a polypropylene mesh with an antiadhesive layer, compares favorably with the Sugarbaker repair with regard to postoperative complications, recurrence rate, and late mesh-related morbidity. ClinicalTrials.gov Identifier: NCT 0418 7235.

There is considerable demand for official statistics on temporary populations to supplement statistics on resident and working populations. Progress has been slow, with temporary population statistics not part of the standard suite of measures produced by national statistical offices. This article adopts the framework for official statistics proposed by Raymer and colleagues as a guide to aspects relating to society, concepts, data, processing, outputs and validation. The article proposes a conceptual framework linking temporary population mobility, defined as a move more than one night in duration that does not entail a change in usual residence, and temporary populations. Using Australia as an example, we discuss various dimensions of temporary mobility that complicate its measurement. We then report the outcomes of a survey of user needs for temporary population statistics along with a desktop review of OECD countries to identify the best formulation of temporary population statistics, and current international practice respectively. The article concludes by proposing two related concepts for temporary populations: population present and person-time, which overcome a number of issues currently impeding progress in this area and discuss their potential implementation.

Good knowledge about genome properties of the populations helps to optimize breeding methods, particularly genomic selection (GS). In oil palm (Elaeis guineensis Jacq.), the first global source of vegetable oil, GS gave promising results. The present study considered two complex oil palm breeding populations, Deli and La Mé, with 943 individuals and 7,324 single-nucleotide polymorphisms (SNPs) from genotyping-by-sequencing. Linkage disequilibrium (LD), haplotype sharing, effective size (Ne), and fixation index (Fst) were investigated. A genetic linkage map was constructed, including 4,252 SNPs and spanning 1,778.52 cM, with an average recombination rate of 2.85 cM/Mbp. The LD at r²=0.3, considered as the minimum to get reliable results for genomic predictions, spanned over 1.05 cM/0.22 Mbp in Deli and 0.9 cM/0.21 Mbp in La Mé. The significant degree of differentiation existing between Deli and La Mé was confirmed by the high Fst value (0.53), the pattern of correlation of SNP heterozygosity and allele frequency among populations, and the decrease of persistence of LD and of haplotype sharing among populations with increasing SNP distance. However, the level of resemblance between the two populations over short genomic distances (correlation of r values between populations >0.6 for SNPs separated by 40% for haplotypes e (

If family farming is supported, it can serve as a foundation for growth and food security. One of Cameroon's biggest development challenges is still food insecurity. Therefore, the purpose of this study was to investigate the situation and key determinants of food security in the northern forest-savanna transition zone of the Central Cameroon Region. To do this, 180 family farmers from Mbangassina, Ntui, Batchenga, and Obala participated in a survey and field observations (January-March 2020; March-May 2021, and July-September 2021). According to this survey and these findings, the useful agricultural area is 4.55 ± 0.21 hectares. Cocoa, yam, cassava, maize, plantain, sweet potato, and peanut are the principal crops mentioned. With a mixed workforce, the vast majority of agricultural work is performed manually (machetes, daba, etc). (Family and external). Seven significant challenges face family farming in these areas: poor market organization, bad road/track conditions, a lack of inputs, seasonal uncertainties/rainfall deficits, challenging access to irrigation, unstable land tenure, challenging access to credit, and challenging access to agricultural equipment. Each community faces unique challenges. The family agricultural industry, which these people rely on for their food security, needs to be saved to overcome these obstacles. According to the findings, expanding access to financial and commercial services will help agricultural operations in the study area increase food security. This will be in line with initiatives made by both governmental and non-governmental organizations to advance agricultural technologies as a way to address the issue of food insecurity.

We describe the performance of the Boolardy Engineering Test Array (BETA), the prototype for the Australian Square Kilometre Array Pathfinder telescope ASKAP. BETA is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarization beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of BETA's performance: sensitivity, beam characteristics, polarimetric properties and image quality. We summarise the astronomical science that it has produced and draw lessons from operating BETA that will be relevant to the commissioning and operation of the final ASKAP telescope., Accepted for publication in PASA

The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to$\sim\!5$yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of$\sim\!162$h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of$0.24\ \mathrm{mJy\ beam}^{-1}$and angular resolution of$12-20$arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.

Internal migration, the movement of people between localities and regions within a country, has resulted in a significant redistribution of national populations. Past cross-national studies have be...

Palladium-doped silica materials with Si CH3 groups were fabricated by sol-gel method under various calcination atmospheres and membranes were made thereof by coating process. The results showed that air atmosphere can lead to the partial oxidation of metallic Pd0 to PdO while N2 and H2 atmospheres can effectively prevent metallic Pd0 from being oxidized. H2 atmosphere is proved to be a more prominent way to slow down the decomposition of organic Si CH3 group than N2 and air atmospheres. The surface area, micropore volume and porosity of palladium-doped silica membrane material calcined in H2 atmosphere are much higher than those calcined in N2 atmosphere. Compared with N2 atmosphere, the palladium-doped silica membranes calcined in H2 atmosphere showed higher H2 permeability and H2/CO2 selectivity before and after the steam exposure. The apparent activation energy of H2 permeation through the palladium-doped silica membrane calcined under H2 atmosphere (2.51 ± 0.05 kJ/mol) was slightly lower than that calcined under N2 atmosphere (2.84 ± 0.04 kJ/mol). Calcination atmosphere plays some role in membrane performance, which has greater influence on the permeance than on the gas permselectivity. Calcination under H2 atmosphere is well conducive to improve the gas permeance and H2 permselectivity of palladium-doped silica membrane.

We report on a search for low-frequency radio variability in 944 bright (> 4Jy at 154 MHz) unresolved, extragalactic radio sources monitored monthly for several years with the Murchison Widefield Array. In the majority of sources we find very low levels of variability with typical modulation indices < 5%. We detect 15 candidate low frequency variables that show significant long term variability (>2.8 years) with time-averaged modulation indices M = 3.1 - 7.1%. With 7/15 of these variable sources having peaked spectral energy distributions, and only 5.7% of the overall sample having peaked spectra, we find an increase in the prevalence of variability in this spectral class. We conclude that the variability seen in this survey is most probably a consequence of refractive interstellar scintillation and that these objects must have the majority of their flux density contained within angular diameters less than 50 milli-arcsec (which we support with multi-wavelength data). At 154 MHz we demonstrate that interstellar scintillation time-scales become long (~decades) and have low modulation indices, whilst synchrotron driven variability can only produce dynamic changes on time-scales of hundreds of years, with flux density changes less than one milli-jansky (without relativistic boosting). From this work we infer that the low frequency extra-galactic southern sky, as seen by SKA-Low, will be non-variable on time-scales shorter than one year., 19 pages, 11 figures

The GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) is a radio continuum survey at 76-227 MHz of the entire southern sky (Declination $ 55$ mJy across an area of $\approx 16,700~\mathrm{deg}^{2}$. From the optical spectra, we identify the dominant physical process responsible for the radio emission from each galaxy: 73 per cent are fuelled by an active galactic nucleus (AGN) and 27 per cent by star formation. We present the local radio luminosity function for AGN and star-forming galaxies at 200 MHz and characterise the typical radio spectra of these two populations between 76 MHz and $\sim 1$ GHz. For the AGN, the median spectral index between 200 MHz and $\sim 1$ GHz, $\alpha_{\mathrm{high}}$, is $-0.600 \pm 0.010$ (where $S \propto \nu^{\alpha}$) and the median spectral index within the GLEAM band, $\alpha_{\mathrm{low}}$, is $-0.704 \pm 0.011$. For the star-forming galaxies, the median value of $\alpha_{\mathrm{high}}$ is $-0.650 \pm 0.010$ and the median value of $\alpha_{\mathrm{low}}$ is $-0.596 \pm 0.015$. Among the AGN population, flat-spectrum sources are more common at lower radio luminosity, suggesting the existence of a significant population of weak radio AGN that remain core-dominated even at low frequencies. However, around 4 per cent of local radio AGN have ultra-steep radio spectra at low frequencies ($\alpha_{\mathrm{low}} < -1.2$). These ultra-steep-spectrum sources span a wide range in radio luminosity, and further work is needed to clarify their nature., Comment: 28 pages, 18 figures, accepted for publication in PASA

Here we present stringent low-frequency 185MHz limits on coherent radio emission associated with a short gamma-ray burst (SGRB). Our observations of the short GRB 180805A were taken with the upgraded Murchison Widefield Array (MWA) rapid-response system, which triggered within 20s of receiving the transient alert from Swift, corresponding to 83.7s post-burst. The SGRB was observed for 30m, resulting in a 3sigma persistent flux density upper-limit of 40.2mJy/beam. Transient searches were conducted at the Swift position of this GRB on 0.5s, 5s, 30s, and 2m timescales, resulting in 3sigma limits of 570-1830, 270-630, 200-420, and 100-200mJy/beam, respectively. We also performed a dedispersion search for prompt signals at the position of the SGRB with a temporal and spectral resolution of 0.5s and 1.28MHz, resulting in a 6sigma fluence upper-limit range from 570Jyms at DM=3000pc/cm^3 (z~2.5) to 1750Jyms at DM=200pc/cm^3 (z~0.1). We compare the fluence prompt emission limit and the persistent upper-limit to SGRB coherent emission models assuming the merger resulted in a stable magnetar. Our observations were not sensitive enough to detect prompt emission associated with the alignment of magnetic fields of a binary neutron star just prior to the merger, from the interaction between the relativistic jet and the interstellar medium or persistent pulsar-like emission from the spin-down of the magnetar. However, in the case of a more powerful SGRB (a gamma-ray fluence an order of magnitude higher than GRB 180805A and/or a brighter X-ray counterpart), our MWA observations may be sensitive enough to detect coherent radio emission from the jet-ISM interaction and/or the magnetar remnant. Finally, we demonstrate that of all current low-frequency radio telescopes, only the MWA has the sensitivity and response times capable of probing prompt emission models associated with the initial SGRB merger event., Comment: 20 pages, 11 figures, accepted for publication in PASA