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Under intensive agriculture, weeds cause heavy losses in crop yield and quality. The existing manual method of weed control is no longer sustainable because of paucity of labours, higher wage, and huge drudgery. Herbicide is an easier, more efficacious, and economical tool for weed control in crops and un-cropped situations. However, the consequences of herbicide use, concerning non-target toxicities, and the evolution of herbicide-resistant weeds have drawn the attention of world communities. Therefore, in this review, we attempt to highlight the potential benefits vis-à-vis harmful consequences of herbicides in diversified crop ecologies across the world. Herbicide use resulted in weed control efficiency of 52–96% in different agro-ecologies. Besides, it could increase grain yield of different arable crops by 19–372% with an additional economic benefit of US$ 305 - US$ 867 over unweeded control. Chemical weed management resulted in gain in net returns by 4–12% over manual weeding (∼two hand weedings) and by 7–247% over the weed-free check in different countries. The majority of herbicides used at recommended doses in crops did not show any direct and/or residual toxicity on soil micro-organisms in agro-ecologies. Environmental conditions may change pesticide impacts on non-target micro-organisms. Over-reliance on herbicides and injudicious use at higher rates may lead to a fragile ecosystem, but judicious use can stimulate productivity, profitability and livelihood security. Hence, integrated weed management (IWM) that can restrict weed populations below threshold level, reduce environmental foot-print, increase cropping system sustainability, and reduce selection pressure for weed resistance to herbicides has been suggested. • Chemical weed management increased 4–12% returns and 52–96% efficacy over manual weeding. • Herbicides at recommended doses did not show any toxicity on soil micro-organisms. • Environmental conditions change impacts of herbicides on non-target microorganisms. • Over-reliance on herbicides and injudicious use may lead to a fragile ecosystem. • Integration of herbicides with suitable methods is recommended for environmental safety. [ABSTRACT FROM AUTHOR]

Usage-based pricing has gained significant traction in recent times with respect to addressing transport challenges. Since such pricing is still in its infancy, at least in the context of urban transport, it is important to understand its implications and, to be specific, any potential equity issues. Based on a hypothetical usage-based pricing scheme together with 2009–2012 Household Travel Survey data of commuters residing in South East Queensland (SEQ), Australia, the results indicate that usage-based road pricing will lead to both horizontal and vertical inequity for some commuters. Most importantly, a greater percentage of these commuters are already transport and socio-economically disadvantaged. They will have no choice but to compromise their quality of life and bear addition financial burdens in the absence of feasible travel alternatives. To ensure that these social costs do not outweigh the benefits, improving the quality of urban transport systems and its integration with urban form and land use, will be required. Until this is achieved, policy makers should incorporate some form of spatial and/or temporal variability within usage-based road pricing in the studied, and similar, urban contexts. [ABSTRACT FROM AUTHOR]

Background Parkinson's disease (PD) is a neurodegenerative disorder that generally begins with asymmetric motor symptoms that persist over time. This suggests that the dysfunction in the nigrostriatal motor circuit may be lateralized. The present study examined whether the asymmetric motor presentation is associated with hemisphere-specific cognitive decline and lateralized gray matter volume loss. Methods Data from comprehensive cognitive tests that measured visuospatial and verbal functions and high-resolution T1-weighted magnetic resonance images of the brain were acquired in 23 PD subjects with left-side motor symptom onset (PDL), 23 PD subjects with right-side onset (PDR), and 23 matched Controls. GM volume differences were assessed using voxel-based morphometry (VBM). Cognitive results and VBM were compared among the three groups, and correlation analyses were performed between those cognitive domains and brain areas that showed significant differences. Results PDL subjects had lower performance on visuospatial memory tasks compared to PDR. Furthermore, PDL subjects experienced lateralized GM loss, which was localized predominantly in the right hemisphere contralateral to the side of motor symptom onset. Visuospatial memory performance in PDL was correlated with GM loss in the right middle frontal gyrus and precuneus. Conclusion These data suggest that the onset of asymmetric motor symptoms in PD may be associated with hemisphere-specific memory decline and lateralized GM loss, particularly in PDL. This study underscores the importance of classifying PD subgroups based on the side of motor symptom onset for clinical care and research to optimize cognitive outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Background: Whereas the motor dysfunction in Parkinson's disease (PD) has been related to deficits in basal ganglia (BG) structures, neural correlates of cognitive changes remain to be fully defined. This study tested the hypothesis that cognitive changes in non-demented PD may be related to cortical gray matter (GM) loss. Methods: High-resolution T1-weighted magnetic resonance images of the brain and comprehensive cognitive function tests were acquired in 40 right-handed, non-demented PD subjects and 40 matched controls. GM changes were assessed using voxel-based morphometry (VBM) in FSL. VBM and cognitive results were compared between PD and controls, and correlation analyses were performed between those brain areas and cognitive domains that showed significant group differences. Results: PD patients demonstrated significant GM reduction localized predominantly in frontal and parieto-occipital regions. Patients also showed reduced performance in fine motor speed and set-shifting compared to controls. Fine motor speed and set-shifting were associated with GM volume in the frontal cortex in controls, whereas these domains were associated primarily with occipital GM regions in PD patients. Conclusions: Non-demented PD subjects demonstrate cortical structural changes in frontal and parieto-occipital regions compared to controls. The association between typically recognized “frontal lobe” function and occipital lobe volume suggested a compensatory role of occipital lobe to primary fronto-striatal pathology in PD. Further longitudinal study of these changing structure–function relationships is needed to understand the neural bases of symptom progression in PD. [Copyright &y& Elsevier]

Abstract: Gas transport properties of five new fluorinated poly(ether imide) (PEI) films containing cardo phthalimidine moiety in the main chain were systematically investigated at three different temperatures (35, 45 and 55°C) under an applied upstream pressure of 3.5bar. The effect of presence of the cardo phthalimidine unit and structural variations of five aromatic dianhydrides in these poly(ether imide) (PEI) films towards the gas permeation of four gases (e.g., CO2, O2, N2 and CH4) and their permselectivity for pair of gases were investigated. The films were prepared by the thermal imidization of the poly(amic acid)s of the reaction products of a new fluorinated diamine, 3,3-bis-[4-{2′-trifluoromethyl 4′-(4″-aminophenyl)phenoxy}phenyl]-2-phenyl-2,3-dihydro-isoindole-1-one with five different dianhydrides namely, BPADA, 6-FDA, BTDA, ODPA and PMDA. All the PEI films exhibited significantly high permeability coefficients than those of common glassy polymers, e.g., cellulose acetate, polysulfone and polycarbonate as well as to other polymers based on cardo phenolphthalein or phthalimide or phthalimidine moiety. PEI-II and PEI-V showed exceptionally high permeability coefficient for all the gases ( Barrers, respectively) along with higher permselectivity towards CO2 relative to CH4 (53.32 and 50.09, repectively) in comparison to cardo phthalimidine based non-flourinated poly(arylene ether sulfones) reported previously. Moreover, high permeability coefficients for O2 ( Barrers, respectively) and comparable permselectivities towards O2 relative to N2 (4.4–6.35) made these series of PEI films highly interesting in comparison to the previously reported phthalimidine based poly(arylene ether sulfone)s or poly(arylene ether ketone)s. Temperature dependency of the permeation and diffusion processes enables to calculate the activation energies of the permeation and diffusion processes for these four different gases through these five PEI films. An attempt has been taken to draw a structure–property correlationship between the repeat unit structures or the functional groups present, and the gas transport properties of this series of PEI films. [Copyright &y& Elsevier]

• An IWM involving pendimethalin + residue + imazethapyr was developed for pea. • It gave 68-70% weed control efficiency without risk of herbicide residue. • It increased pea yield by 77-80% and had higher profitability. • It may reduce use of pendimethalin by 50% and imazethapyr by 25% and their intake. • Residue mulch gave 26-30% higher pea yield than cono-weeding. Vegetable pea (hereafter referred to as pea) is heavily infested with weeds, which can cause yield losses up to 39%. Only pre-emergence herbicide is not enough to control diverse weeds. Its efficacy is greatly affected by soil surface dryness during winter. Integration of other options with herbicides may provide effective weed management. Therefore, this experiment was designed to evaluate the effects of combinations of pre- and/or post-emergence herbicides, residue retention, mechanical weeding on weeds in pea. Results showed that the applications of pendimethalin 0.5 kg a.i. (active ingredient) ha-1 as pre-emergence + residue 2 t ha-1 followed by imazethapyr 0.075 kg a.i. ha-1 as post-emergence gave comparable pea yield with weed-free control, which was 79.6% and 77.3% higher, respectively in first and second year than that in unweeded control. This treatment resulted in higher weed control efficiency (68% and 70%), leaf area index (4.90 and 5.52) and biomass (5.38 and 5.72 g plant-1) of pea, net returns and net benefit:cost than most other treatments. Contrast analysis revealed that crop residue mulch was superior to no residue and cono-weeding, by giving 41.9-55.5% and 25.5-29.6% higher pea yield, respectively. The residues of pendimethalin, imazethapyr, and quizalofop in pea and soil were below detectable level (0.05 mg kg-1) in all treatments, except two treatments, which, otherwise, had pendimethalin residue below maximum residue limit (0.1 mg kg-1). Thus, the combination of pendimethalin, crop residue, and imazethapyr could lead to better weed management and higher pea productivity and profitability without risks of herbicide residue in pea and soil. It would reduce the use and intake of residues into environment of pendimethalin by 50% and imazethapyr by 25%. [ABSTRACT FROM AUTHOR]