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Abstract New exogenous cis,cis-muconic acid biosynthetic pathway genes were expressed in Saccharomyces cerevisiae. The xylose isomerase gene from Bacteroides valgutus and pentose phosphate pathway genes from S. cerevisiae were overexpressed in the yeast strain. The strain was further modified by the overexpression of gene Aro1 (with a stop codon of AroE) and a feedback-resistant Aro4opt mutant gene from S. cerevisiae. Under oxygen-limited conditions, it produced 65 mg/L cis,cis-muconic acid from xylose. Co-fermentation of 88 g/L glucose and 50 g/L xylose generated 54 g/L ethanol and 248 mg/L cis,cis-muconic acid. Under aerobic conditions, muconic acid titer reached 424 mg/L. With the supplement of 1 g/L catechol, 1286 mg/L muconic acid was produced. Fermentation of an oil palm empty fruit bunch hydrolysate resulted in 31.3 g/L ethanol and 53.4 mg/L muconic acid. This is the first report on the production of muconic acid from lignocellulosic biomass hydrolysate using a recombinant xylose-fermenting yeast.

Plants under salt stress require additional energy supply to fuel salt tolerance mechanisms and growth. Bandehagh and Taylor (2020) establish that plants must strike a balance between energy supply and demand to maintain growth and development during salt stress. This review (1) summaries how salt stress affects different physiological and biochemical process altering the abundance of different metabolites that are feeding into regular and alternative respiratory pathways and shunts; (monomeric complex I, dimeric complex III and I + III2 supercomplex) found to be higher in halophyte mitochondria in comparison with glycophyte, implying efficient electron transfer from complex I to complex III in halophyte mitochondria. Further, the stability of ATP synthase (complex V) also found to be higher in halophyte suggesting halophyte mitochondria better equipped to supply additional ATP required to support salt stress response.Synthesis of organic compatible solutes is an important component for plant salt stress tolerance. In this regard, proline plays an important role in protecting plants from under salinity conditions and showed that salt tolerance is associated with changes in lipid metabolic processes. They also discovered the important role of phosphatidylserine (PS) in mediating enzyme activity, and exogenous application of PS alleviated the effects of NaCl tissue toxicity. The results showed that the superior K + retention ability in both mature and elongation zone of rice root is the key trait conferring its differential salinity stress tolerance. They suggested that besides the superior ability to activate root H + -ATPase pump operation, this key trait is also related to the reduced sensitivity of K + efflux channels to reactive oxygen species and the lower upregulation in OsGORK and higher upregulation of OsAKT1.A key trait long recognized to improve salinity tolerance in many plants is the maintenance of a low Na + /K + ratio. Transient expression experiment showed that JcHDZ07 is a nuclear-localized protein.In improving Na + exclusion ability to maintain root ion homeostasis to ensure a relatively 9 low shoot Na + concentration under saline conditions; 2) maintaining a high shoot sugar content under saline conditions which is enabled by protecting photosystems structures, enhancing photosynthetic performance and sucrose synthetase activity, and inhibiting sucrose degradation. Further, authors suggested that targeting the key genes related to the regulatory mechanisms could provide opportunities to breed more salt tolerant sweet sorghum.Overall, we hope this special issue of benefit to plant breeders and land managers by delivering novel information and insights on the salinity stress response, signalling and adaptive mechanisms operating in plants.

Adolescents frequently engage in risky behaviours such as binge drinking. Binge drinking, in turn, perturbs neurodevelopment reinforcing reward seeking behaviour in adulthood. Current animal models are limited in their portrayal of this behaviour and the assessment of neuroimmune involvement (specifically the role of Toll-like receptor 4 (TLR4)). Therefore, the aims of this project were to develop a more relevant animal model of adolescent alcohol exposure and to characterise its effects on TLR4 signalling and alcohol-related behaviours later life. Balb/c mice received a short (P22-P25), low dose alcohol binge during in early adolescence, and underwent tests to investigate anxiety (elevated plus maze), alcohol seeking (conditioned place preference) and binge drinking behaviour (drinking in the dark) in adulthood. Four doses of alcohol during adolescence increased alcohol-induced conditioned place preference and alcohol intake in adulthood. However, this model did not affect basal elevated plus maze performance. Subsequent analysis of nucleus accumbal mRNA, revealed increased expression of TLR4-related mRNAs in mice who received alcohol during adolescence. To further elucidate the role of TLR4, (+)-Naltrexone, a biased TLR4 antagonist was administered 30 min before or after the adolescent binge paradigm. When tested in adulthood, (+)-Naltrexone treated mice exhibited reduced alcohol intake however, alcohol seeking and anxiety behaviour was unaltered. This study highlights that even a small amount of alcohol, when given during a critical neurodevelopmental period, can potentiate alcohol-related behaviours and TLR4 activation later in life. Interestingly, attenuation of TLR4 before or after adolescent alcohol exposure reduced only binge alcohol intake in adulthood.

Silicon microdosimetry is a promising technology for heavy ion therapy (HIT) quality assurance, because of its sub-mm spatial resolution and capability to determine radiation effects at a cellular level in a mixed radiation field. A drawback of silicon is not being tissue-equivalent, thus the need to convert the detector response obtained in silicon to tissue. This paper presents a method for converting silicon microdosimetric spectra to tissue for a therapeutic 12C beam, based on Monte Carlo simulations. The energy deposition spectra in a 10 μm sized silicon cylindrical sensitive volume (SV) were found to be equivalent to those measured in a tissue SV, with the same shape, but with dimensions scaled by a factor κ equal to 0.57 and 0.54 for muscle and water, respectively. A low energy correction factor was determined to account for the enhanced response in silicon at low energy depositions, produced by electrons. The concept of the mean path length [Formula: see text] to calculate the lineal energy was introduced as an alternative to the mean chord length [Formula: see text] because it was found that adopting Cauchy's formula for the [Formula: see text] was not appropriate for the radiation field typical of HIT as it is very directional. [Formula: see text] can be determined based on the peak of the lineal energy distribution produced by the incident carbon beam. Furthermore it was demonstrated that the thickness of the SV along the direction of the incident 12C ion beam can be adopted as [Formula: see text]. The tissue equivalence conversion method and [Formula: see text] were adopted to determine the RBE10, calculated using a modified microdosimetric kinetic model, applied to the microdosimetric spectra resulting from the simulation study. Comparison of the RBE10 along the Bragg peak to experimental TEPC measurements at HIMAC, NIRS, showed good agreement. Such agreement demonstrates the validity of the developed tissue equivalence correction factors and of the determination of [Formula: see text].

Natural ecosystems are threatened by climate change, fragmentation, and non-native species. Dispersal-limitation potentially compounds impacts of these factors on plant diversity, especially in isolated vegetation patches. Changes in climate can impact the phenology of native species in distinct ways from non-natives, potentially resulting in cascading impacts on native communities. Few empirical studies have examined the combined effects of climate change and dispersal limitation on community diversity or phenology. Using a five-year dispersal-restriction experiment in an invaded semi-arid annual plant system in Western Australia, we investigated the interactive effects of dispersal-restriction and inter-annual rainfall variation on community composition, species dominance and seed production timing. We found inter-annual rainfall variation to be the principal driver of community dynamics. Drought years had long-term, stable effects on community composition, with evidence of shifts from native toward non-native dominance. Surprisingly, community composition remained largely unchanged under dispersal restriction. A subtle dispersal rescue effect was evident for a dominant native annual forb and a dominant annual non-native grass but only in average rainfall years. The timing of seed production was primarily driven by annual rainfall with native and non-native grasses having opposite responses. There was no evidence that inter-annual variation in seeding timing affected community diversity over time. Our study demonstrates that dispersal is not a major factor in driving community diversity in this invaded, semi-arid system. Results do suggest, however, that increases in drought frequency likely benefit non-native species over natives in the long term. Climate Change Ecology, 2 ISSN:2666-9005

Anthropogenically generated underwater noise in the marine environment is ubiquitous, comprising both intense impulse and continuous noise. The installation of offshore wind farms across the North Sea has triggered a range of ecological questions regarding the impact of anthropogenically produced underwater noise on marine wildlife. Our interest is on the impact on the "passive drifters," i.e., the early life stages of fish that form the basis of fish populations and are an important prey for pelagic predators. This study deals with the impact of pile driving and operational noise generated at offshore wind farms on Dicentrarchus labrax (sea bass) larvae.

To describe physical activity (PA) and inactivity levels of Filipino youth aged 14-16 y.PA type and patterns were assessed in an adolescent cohort enrolled in the Cebu Longitudinal Health and Nutrition Survey.A total of 1053 males (aged 15.6+/-0.5 y; body mass index (BMI)=18.6+/-2.6 kg/m(2)) and 990 females (aged 14.6+/-0.5 y; BMI=18.8+/-2.4 kg/m(2)).PA was assessed by (1) self-reported usual PA (questionnaire); (2) 24-h objective monitoring (Caltrac accelerometer); and (3) 24 h recalls of PA during the objectively monitored time frame.As measured by Caltrac, males expended 378.0+/-164.5 kcal and females 271.0+/-105.4 kcal. The measurement approaches employed agreed in expected ways, given the limitations of each. Together the approaches used indicated that the primary sources of PA for this population are chores and active commuting. In all, 40% of the sample walked to school, less than 1% rode a bicycle, 22% rode in/on motorized transport, and 37% used some combination of walking and motorized transport. Further, gender differences exist for type, frequency, and duration of physical activities performed by Filipino youth. Specifically, females report engaging in few leisure-time physical activities and more household chores. In total, 48% of Filipino youth report watching > or =2 h/day of television; relatively few youth (7%) report watching >4 h/day at this time. An 18% of males report no vigorous activities compared to 87% of females.Clear gender differences in PA patterns and levels exist in Filipino adolescents. Nonsport/exercise type activities (eg chores and active commuting) currently provide a large proportion of daily activity for both males and females, however. It is anticipated that as modernization and technological advancement continue in this developing country, these primary sources of PA will decrease.