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Mankind’s quest to reduce its dependency on fossil fuel involves biomass as a promising alternative. However, direct application of raw biomass faces problems such as high moisture content, low heating value, and poor grindability. Pyrolysis is one of the pre-treatment methods to improve biomass properties particularly its energy density. This study is aimed at investigating the pyrolysis of oil palm trunk (OPT) into biocoal and its suitability for solid fuel applications in terms of slagging and fouling tendencies, bulk density, proximate and ultimate analysis, higher heating value, energy densification ratio, and mass and energy yield. The biocoal was produced using a top-lit, updraft reactor with a peak temperature of 550 °C and fixed air flowrate of 4.63 L/min. The bulk density of OPT biocoal was 87.7 kg/m3 which is 4.63% lower than that of original OPT due to the increased porosity. The elemental composition of our biocoal resembles lignite. The volatile matter content decreased by a factor of 1.87 while the fixed carbon content and higher heating value (HHV) increased from 4.29 to 30.9% and from 14.5 to 19.6 MJ/kg, respectively. The HHV of biocoal increased by a factor of 1.36 relative to that of raw OPT; however, the resulting energy yield was low (37.6 ± 1.9%) due to a low biocoal yield of 27.8 ± 1.4%. The ash content increased by a factor of 1.5, resulting in an ash content of 27.8 wt% for biocoal. This increment may exacerbate the slagging and fouling propensity in furnaces and boilers as indicated by the slagging and bed agglomeration index which increased from 2.0 to 5.2 and from 0.4 to 0.7, respectively. Demineralization, a lower pyrolysis temperature and subsequent briquetting of OPT biocoal are suggested to improve its fuel properties for co-combustion in coal-firing power plants.

Gemmata obscuriglobus is a Gram-negative bacterium with several intriguing biological features. Here, we present a complete, de novo whole genome assembly for G. obscuriglobus which consists of a single, circular 9 Mb chromosome, with no plasmids detected. The genome was annotated using the NCBI Prokaryotic Genome Annotation pipeline to generate common gene annotations. Analysis of the rRNA genes revealed three interesting features for a bacterium. First, linked G. obscuriglobus rrn operons have a unique gene order, 23S-5S-16S, compared to typical prokaryotic rrn operons (16S-23S-5S). Second, G. obscuriglobus rrn operons can either be linked or unlinked (a 16S gene is in a separate genomic location from a 23S and 5S gene pair). Third, all of the 23S genes (5 in total) have unique polymorphisms. Genome analysis of a different Gemmata species (SH-PL17), revealed a similar 23S-5S-16S gene order in all of its linked rrn operons and the presence of an unlinked operon. Together, our findings show that unique and rare features in Gemmata rrn operons among prokaryotes provide a means to better define the evolutionary relatedness of Gemmata species and the divergence time for different Gemmata species. Additionally, these rrn operon differences provide important insights into the rrn operon architecture of common ancestors of the planctomycetes.

Biochar prepared from organic waste through pyrolysis, thermal combustion in an inert environment, generates a stable form of carbon. The review of established literature reveals that conversion of organic matter into biochar and its addition to soil also reduces the negative effects of carbon aerosols on human health and greenhouse gas effects on environment through carbon sequestration. Physicochemical properties of biochar such as nutrient sorption capacity, pH, pore structure, particle size, surface area, and mineral content play a vital role in determining the soil structure and function. Biochar addition to soil exerts measurable changes in physicochemical soil properties such as bulk density, water-holding capacity, pH and cation exchange capacity, microbial community structure, and their interrelated functions in soil. However, addition of biochar to specific soil improves the soil fertility, and consequently improves the crop yield. It is concluded that optimized pyrolysis of organic waste for biochar production and its use for soils need diversified investigation in diverse environmental conditions.

The extensive use of peat moss as potting medium in nurseries worldwide is not sustainable causing peatland depletion and greenhouse gas emissions. This research seeks to explore whether wood biochar produced by the environment-friendly flame curtain method can partially substitute peat moss in plant nurseries without affecting plant growth and health. Biochar was produced from durian wood logs in a top-quenched Kon-Tiki earth kiln, crushed, and mixed with peat moss at dosages of 0, 1, 2.5 and 5% (w/w). Durian seedlings were grown in 2.5 L polybags arranged in randomised complete block design with 4 replicates per treatment. Plant height, collar diameter, pH, moisture content, number of branches and leaves, and plant health were monitored weekly for 94 days. Liquid fish fertiliser was used as organic fertiliser. Our results demonstrated that biochar can substitute at least 5% (w/w) peat moss without negatively affecting plant height, collar diameter, number of leaves and branches, and plant health. In addition, organic fertiliser is not required during the first 3 months of cultivation resulting in cost savings to the nursery operator. Plant height was found to be the most accurate yet simple monitoring parameter studied. A better understanding of the effect of higher biochar application rates as well as the number of times the potting medium can be reused without loss of potting medium properties and health can help to further cut nursery cost and reduce reliance on peat moss.

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This article traces the history of Business Economics, focusing first on its institutional history—its beginnings, key contributors, debates on its content, and shifts in editorial policy. It then turns to discussion of particular articles that are distinguished either by the judgment of Business Economics’ Editorial Board or whose authors have been honored by the National Association for Business Economics for their outstanding service. The article also presents trends in the sources and content of Business Economics over its 50-year history.

Background The primary metric extracted from the polysomnogram in patients with sleep apnea is the apnea-hypopnea index (or respiratory disturbance index) and its derivatives. Other phenomena of possible importance such as periods of stable breathing, features suggestive of high respiratory control loop gain, and sleep fragmentation phenotypes are not commonly generated in clinical practice or research. A broader phenotype designation can provide insights into biological processes, and possibly clinical therapy outcome effects. Methods The dataset used for this study was the archived baseline diagnostic polysomnograms from the Apnea Positive Pressure Long-term Efficacy Study (APPLES). The electrocardiogram (ECG)-derived cardiopulmonary coupling sleep spectrogram was computed from the polysomnogram. Sleep fragmentation phenotypes used thresholds of sleep efficiency (SE) ≤ 70%, non-rapid eye movement (NREM) sleep N1 ≥ 30%, wake after sleep onset (WASO) ≥ 60 min, and high frequency coupling (HFC) on the ECG-spectrogram ≤ 30%. Sleep consolidation phenotypes used thresholds of SE ≥ 90%, WASO ≤ 30 min, HFC ≥ 50% and N1 ≤ 10%. Multiple and logistic regression analysis explored cross-sectional associations with covariates and across phenotype categories. NREM vs. REM dominant apnea categories were identified when the NREM divided by REM respiratory disturbance index (RDI) was > 1. Results The data was binned first into mild, moderate, severe and extreme categories based on the respiratory disturbance index of

The quorum sensing (QS) dependent behaviour of micro-organisms, in particular expression of virulence genes, biofilm formation and dispersal, have provided impetus for investigating practical approaches to interfere with microbial QS. This study tests Halomonas pacifica and Marinobacter hydrocarbonoclasticus, two halophilic marine micro-organism, for their AI-2 dependent QS signalling and the effect of two well-known quorum-sensing inhibitors (QSIs), patulin and penicillic acid, on biofilm formation. We report, for the first time, the successful amplification of a putative luxS gene in H. pacifica using degenerated primers and AI-2 dependent QS as well as inhibition using QSIs. Penicillic acid had a strong inhibitory effect on AI-2 induction of H. pacifica at non-growth inhibitory concentrations, while patulin has an adverse effect only at the highest concentration (25 μM). QSIs effect on biofilm forming capability was isolate specific, with maximum inhibition at 25 μM of patulin in H. pacifica. In M. hydrocarbonoclasticus, no adverse effects were noted at any tested concentration of either QSIs. Detection of bioluminescence and the presence of a putative luxS gene provide biochemical and genetic evidence for the production of a signalling molecule(s) which is the essential first step in characterizing H. pacifica QS. This study highlights the importance of AI-2 dependent QS in a marine setting, not previously reported. It further suggests that QSI compounds must be selected in the specific system in which they are to function, and they cannot easily be transferred from one QS system to another.

Ultrasound-guided wire localization of impalpable lesions is a well-recognized technique in the management of breast pathology, but its use in the head and neck is not well described. Performed under local anesthesia, high-resolution ultrasound provides real-time imaging for accurate placement of the wire resulting in fewer complications. Wire localization can focus the surgical approach, which reduces operating time and minimizes trauma to surrounding tissues. In this technical note, we describe two cases of pre-operative ultrasound-guided wire localization to facilitate the surgical excision of impalpable neck lesions.

Deuterated rhamnolipids were produced using strain AD7 of Pseudomonas aeruginosa, which was progressively adapted to increasing levels of deuterium in D(2)O and carbon substrates. Fourteen different deuterated rhamnolipid structures, including structural isomers, were produced which is similar to normal protonated structures. There were two main products monorhamnolipid Rha-C(10)-C(10) and dirhamnolipid Rha(2)-C(10)-C(10). The levels of deuteration varied from 16% with 25% D(2)O + h-glycerol to 90% with 100% D(2)O + d-glycerol. When d-tetradecane was used with H(2)O, virtually all the deuterium appeared in the lipid chains while using h-tetradecane + D(2)O led to the majority of deuterium in the sugars. The adaptation to growth in deuterium appeared to be metabolic since no genetic changes could be found in the key rhamnolipid biosynthetic genes, the rhamnosyl transferases RhlB and RhlC. Deuterated sophorolipids were similarly produced using Candida bombicola and Candida apicola although in this case, no adaptation process was necessary. Up to 40 different sophorolipids were produced by these yeasts. However, unlike the rhamnolipids, use of D(2)O did not lead to any deuteration of the lipid chains, but direct incorporation into the lipid was achieved using d-isostearic acid. The results from these experiments show the feasibility of producing deuterated bioactive compounds from microorganisms coupled with the possibility of manipulating the pattern of labelling through judicious use of different deuterated substrates.

Tissue engineering and regenerative medicine are rapidly developing fields that use cells or cell-based constructs as therapeutic products for a wide range of clinical applications. Efforts to commercialise these therapies are driving a need for capable, scaleable, manufacturing technologies to ensure therapies are able to meet regulatory requirements and are economically viable at industrial scale production. We report the first automated expansion of a human bone marrow derived mesenchymal stem cell population (hMSCs) using a fully automated cell culture platform. Differences in cell population growth profile, attributed to key methodological differences, were observed between the automated protocol and a benchmark manual protocol. However, qualitatively similar cell output, assessed by cell morphology and the expression of typical hMSC markers, was obtained from both systems. Furthermore, the critical importance of minor process variation, e.g. the effect of cell seeding density on characteristics such as population growth kinetics and cell phenotype, was observed irrespective of protocol type. This work highlights the importance of careful process design in therapeutic cell manufacture and demonstrates the potential of automated culture for future optimisation and scale up studies required for the translation of regenerative medicine products from the laboratory to the clinic.

Classical boundary lubrication is widespread in engineering applications and is also thought to exist in biological systems. It minimizes friction and wear by ensuring that rubbing takes place between the 'boundary' layers of surfactant molecules that coat each surface, rather than between the substrates themselves. Experiments with boundary-lubricant coated sliding surfaces immersed in water now show that friction stress can be reduced by two orders of magnitude or more, relative to its value in dry air. The mechanism may involve the hydration of charged head groups that can then slide easily on the surfaces to which they are attached. This new type of boundary lubrication could be useful for developing better lubricated artificial implants and new medical treatments for joint problems. Boundary lubrication, in which the rubbing surfaces are coated with molecular monolayers, has been studied extensively for over half a century1,2,3,4,5,6,7. Such monolayers generally consist of amphiphilic surfactants anchored by their polar headgroups; sliding occurs at the interface between the layers, greatly reducing friction and especially wear of the underlying substrates. This process, widespread in engineering applications, is also predicted to occur in biological lubrication via phospholipid films8,9, though few systematic studies on friction between surfactant layers in aqueous environments have been carried out5,10. Here we show that the frictional stress between two sliding surfaces bearing surfactant monolayers may decrease, when immersed in water, to as little as one per cent or less of its value in air (or oil). We attribute this to the shift of the slip plane from between the surfactant layers, to the surfactant/substrate interface. The low friction would then be due to the fluid hydration layers surrounding the polar head groups attached to the substrate. These results may have implications for future technological and biomedical applications.

Specular neutron reflection has been used to determine the structure and composition of the mixed ionic–non-ionic surfactants adsorbed at the hydrophilic silica solid/water interface. Measurements on two different mixed surfactant systems are reported: the cationic/nonionic mixture of hexadecyltrimethyl ammonium bromide, C16TAB, and hexaethylene glycol monododecyl ether, C12E6, and the anionic/nonionic mixture of sodium dodecyl sulfate, and C12E6. For the C16TAB–C12E6 mixture, pH is shown to have a dramatic effect on the relative affinity for adsorption of the two surfactants at the interface.