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PloS One 2022Peatlands account for 15 to 30% of the world's soil carbon (C) stock and are important controls over global nitrogen (N) cycles. However, C and N concentrations are...
Peatlands account for 15 to 30% of the world's soil carbon (C) stock and are important controls over global nitrogen (N) cycles. However, C and N concentrations are known to vary among peatlands contributing to the uncertainty of global C inventories, but there are few global studies that relate peatland classification to peat chemistry. We analyzed 436 peat cores sampled in 24 countries across six continents and measured C, N, and organic matter (OM) content at three depths down to 70 cm. Sites were distinguished between northern (387) and tropical (49) peatlands and assigned to one of six distinct broadly recognized peatland categories that vary primarily along a pH gradient. Peat C and N concentrations, OM content, and C:N ratios differed significantly among peatland categories, but few differences in chemistry with depth were found within each category. Across all peatlands C and N concentrations in the 10-20 cm layer, were 440 ± 85.1 g kg-1 and 13.9 ± 7.4 g kg-1, with an average C:N ratio of 30.1 ± 20.8. Among peatland categories, median C concentrations were highest in bogs, poor fens and tropical swamps (446-532 g kg-1) and lowest in intermediate and extremely rich fens (375-414 g kg-1). The C:OM ratio in peat was similar across most peatland categories, except in deeper samples from ombrotrophic tropical peat swamps that were higher than other peatlands categories. Peat N concentrations and C:N ratios varied approximately two-fold among peatland categories and N concentrations tended to be higher (and C:N lower) in intermediate fens compared with other peatland types. This study reports on a unique data set and demonstrates that differences in peat C and OM concentrations among broadly classified peatland categories are predictable, which can aid future studies that use land cover assessments to refine global peatland C and N stocks.
Topics: Carbon; Soil; Wetlands; Nitrogen
PubMed: 36417456
DOI: 10.1371/journal.pone.0275149 -
Microbial Ecology Oct 2023Arctic soils are constantly subjected to microbial invasion from either airborne, marine, or animal sources, which may impact local microbial communities and ecosystem...
Arctic soils are constantly subjected to microbial invasion from either airborne, marine, or animal sources, which may impact local microbial communities and ecosystem functioning. However, in winter, Arctic soils are isolated from outside sources other than snow, which is the sole source of microorganisms. Successful colonisation of soil by snow microorganisms depends on the ability to survive and compete of both, the invading and resident community. Using shallow shotgun metagenome sequencing and amplicon sequencing, this study monitored snow and soil microbial communities throughout snow melt to investigate the colonisation process of Arctic soils. Microbial colonisation likely occurred as all the characteristics of successful colonisation were observed. The colonising microorganisms originating from the snow were already adapted to the local environmental conditions and were subsequently subjected to many similar conditions in the Arctic soil. Furthermore, competition-related genes (e.g. motility and virulence) increased in snow samples as the snow melted. Overall, one hundred potentially successful colonisers were identified in the soil and, thus, demonstrated the deposition and growth of snow microorganisms in soils during melt.
Topics: Soil; Ecosystem; Snow; Arctic Regions
PubMed: 36939866
DOI: 10.1007/s00248-023-02204-y -
The New Phytologist Dec 2018Contents Summary 1122 I. Introduction 1122 II. Are there consistent patterns in diversity of mycorrhizal fungal genotypes and species across space? 1125 III. What is the... (Review)
Review
Contents Summary 1122 I. Introduction 1122 II. Are there consistent patterns in diversity of mycorrhizal fungal genotypes and species across space? 1125 III. What is the variation in functional traits and genes of mycorrhizal fungi at different taxonomic scales? 1125 IV. How will environmental change impact the relationships between genotypic and species diversity of mycorrhizal fungi and ecosystem function? 1126 V. Conclusions: considerations for future MEF research 1127 Acknowledgements 1127 References 1127 SUMMARY: Both genotypes and species of mycorrhizal fungi exhibit considerable variation in traits, and this variation can result in their diversity regulating ecosystem function. Yet, the nature of mycorrhizal fungal diversity-ecosystem function (MEF) relationships for both genotypes and species is currently poorly defined. New experiments should reflect the richness of genotypes and species in nature, but we still lack information about the extent to which fungal populations in particular are structured. Sampling designs should quantify the diversity of mycorrhizal fungal genotypes and species at three key broad spatial scales (root fragment, root system and interacting root systems) in order to inform manipulation experiments and to test how mycorrhizal fungal diversity both responds, and confers resilience to, environmental drivers.
Topics: Biodiversity; Genotype; Mycorrhizae; Plants; Quantitative Trait, Heritable; Species Specificity
PubMed: 29393517
DOI: 10.1111/nph.15010 -
Micromachines May 2022Wearable flexible piezo-resistive pressure sensors hold a wide-ranging potential in human health monitoring, electronic skin, robotic limbs, and other human-machine...
Wearable flexible piezo-resistive pressure sensors hold a wide-ranging potential in human health monitoring, electronic skin, robotic limbs, and other human-machine interfaces. Out of the most successful recent efforts for arterial pulse monitoring are sensors with micro-patterned conductive elastomers. However, a low-current output signal (typically in the range of nano-amperes) and bulky and expensive measurement equipment for useful signal acquisition inhibits their wearability. Herein, through a finite element analysis we establish the design rules for a highly sensitive piezo-resistive pressure sensor with an output that is high enough to be detectable by simple and inexpensive circuits and therefore ensure wearability. We also show that, out of four frequently reported micro-feature shapes in micro-patterned piezo-resistive sensors, the micro-dome and micro-pyramid yield the highest sensitivity. Furthermore, investigations of different conductivity values of micro-patterned elastomers found that coating the elastomer with a conductive material (usually metallic) leads to higher current response when compared to composited conductive elastomers. Finally, the geometric parameters and spatial configurations of micro-pyramid design of piezo-resistive sensors were optimized. The results show that an enhanced sensitivity and higher current output is achieved by the lower spatial density configuration of three micro-features per millimeter length, a smaller feature size of around 100 μm, and a 60-50 degrees pyramid angle.
PubMed: 35744452
DOI: 10.3390/mi13060838 -
Biology Jul 2021Many separate fields and practices nowadays consider microbes as part of their legitimate focus. Therefore, microbiome studies may act as unexpected unifying forces... (Review)
Review
Many separate fields and practices nowadays consider microbes as part of their legitimate focus. Therefore, microbiome studies may act as unexpected unifying forces across very different disciplines. Here, we summarize how microbiomes appear as novel major biological players, offer new artistic frontiers, new uses from medicine to laws, and inspire novel ontologies. We identify several convergent emerging themes across ecosystem studies, microbial and evolutionary ecology, arts, medicine, forensic analyses, law and philosophy of science, as well as some outstanding issues raised by microbiome studies across these disciplines and practices. An 'epistemic revolution induced by microbiome studies' seems to be ongoing, characterized by four features: (i) an ecologization of pre-existing concepts within disciplines, (ii) a growing interest in systemic analyses of the investigated or represented phenomena and a greater focus on interactions as their root causes, (iii) the intent to use openly multi-scalar interaction networks as an explanatory framework to investigate phenomena to acknowledge the causal effects of microbiomes, (iv) a reconceptualization of the usual definitions of which individuals are worth considering as an explanans or as an explanandum by a given field, which result in a fifth strong trend, namely (v) a de-anthropocentrification of our perception of the world.
PubMed: 34356506
DOI: 10.3390/biology10070651 -
European Journal of Applied Physiology Mar 2023Microcurrent is a non-invasive and safe electrotherapy applied through a series of sub-sensory electrical currents (less than 1 mA), which are of a similar magnitude to... (Review)
Review
Microcurrent is a non-invasive and safe electrotherapy applied through a series of sub-sensory electrical currents (less than 1 mA), which are of a similar magnitude to the currents generated endogenously by the human body. This review focuses on examining the physiological mechanisms mediating the effects of microcurrent when combined with different exercise modalities (e.g. endurance and strength) in healthy physically active individuals. The reviewed literature suggests the following candidate mechanisms could be involved in enhancing the effects of exercise when combined with microcurrent: (i) increased adenosine triphosphate resynthesis, (ii) maintenance of intercellular calcium homeostasis that in turn optimises exercise-induced structural and morphological adaptations, (iii) eliciting a hormone-like effect, which increases catecholamine secretion that in turn enhances exercise-induced lipolysis and (iv) enhanced muscle protein synthesis. In healthy individuals, despite a lack of standardisation on how microcurrent is combined with exercise (e.g. whether the microcurrent is pulsed or continuous), there is evidence concerning its effects in promoting body fat reduction, skeletal muscle remodelling and growth as well as attenuating delayed-onset muscle soreness. The greatest hindrance to understanding the combined effects of microcurrent and exercise is the variability of the implemented protocols, which adds further challenges to identifying the mechanisms, optimal patterns of current(s) and methodology of application. Future studies should standardise microcurrent protocols by accurately describing the used current [e.g. intensity (μA), frequency (Hz), application time (minutes) and treatment duration (e.g. weeks)] for specific exercise outcomes, e.g. strength and power, endurance, and gaining muscle mass or reducing body fat.
Topics: Humans; Muscle, Skeletal; Exercise; Electric Stimulation Therapy; Adaptation, Physiological; Acclimatization
PubMed: 36399190
DOI: 10.1007/s00421-022-05097-w -
Indian Journal of Ophthalmology Nov 2022Manual small-incision cataract surgery (MSICS) has a major role in tackling cataract blindness in our country. Cauterization of sclera is one of the important steps... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
Manual small-incision cataract surgery (MSICS) has a major role in tackling cataract blindness in our country. Cauterization of sclera is one of the important steps performed in MSICS to have bloodless field during surgery. Only few studies have addressed the effect of cautery on post-operative astigmatism. The present study is designed to evaluate the effect of cautery on surgically induced astigmatism in Indian patients.
METHODS
The study was designed as a prospective randomized trial conducted in a tertiary health care institution over a period of 2 years. A total of 150 eyes were randomized into two groups. The study group (Group 1, n = 75) underwent MSICS with cauterization using wetfield bipolar cautery with 4 amperes power. In the control group (Group 2, n = 75), no cauterization was performed. Surgically induced astigmatism was calculated using Naesers polar value method and compared between these two groups up to 60 days post-operatively.
RESULTS
Data from 150 eyes were available for evaluation. The net post-operative astigmatic value was 1.01 ± 0.21, 1.04 ± 0.19, and 1.03 ± 0.22 D on the 1, 7, and 30 post-operative days, respectively, showing a stable trend in patients undergoing cauterization. In Group 2, the net post-operative astigmatic values observed were 0.47 ± 0.11 D, 0.54 ± 0.10, and 0.54 ± 0.09 D on the 1, 7, and 30 post-operative days, respectively. The mean value of surgically induced astigmatism at 2 months post-operatively with and without cautery was 0.60 ± 0.20 D at 90° and 0.47 ± 0.10 D at 90°. The difference was not statistically significant (P = 0.08).
CONCLUSION
The results of this study show that the use of cautery in MSICS is not associated with a higher surgically induced post-operative astigmatism. The magnitude of surgically induced astigmatism decreases with time.
Topics: Humans; Astigmatism; Prospective Studies; Cataract Extraction; Cataract; Surgical Wound; Cautery
PubMed: 36308120
DOI: 10.4103/ijo.IJO_1540_22 -
Euphytica: Netherlands Journal of Plant... 2021It has been estimated that up to 90% of human exposure to cadmium is through food, and that cadmium within rice grains can be a major contributor to that dietary source....
UNLABELLED
It has been estimated that up to 90% of human exposure to cadmium is through food, and that cadmium within rice grains can be a major contributor to that dietary source. In this study genome wide association mapping was conducted on the Bengal and Assam Aus Panel (BAAP) of rice to identify quantitative trait loci and candidate genes for lowering grain cadmium. Field experiments were conducted over two years under two different irrigation systems: continually flooded and alternate wetting and drying (AWD). There was significant effects of water treatment, genotype, and genotype by water treatment interaction. Importantly, AWD increased grain cadmium, on average, by 49.6% and 108.8% in year 1 and 2 respectively. There was between 4.6 and 28 fold variation in cadmium concentration. A total of 58 QTLs were detected but no loci are clearly specific to one water regime despite approximately 20% of variation attributable to genotype by water regime interaction. A number of QTLs were consistent across most water treatments and years. These included QTLs on chromosome 7 (7.23-7.61, 8.93-9.04, and 29.12-29.14 Mbp), chromosome 5 (8.66-8.72 Mbp), and chromosome 9 (11.46-11.64 Mbp). Further analysis of the loci on chromosome 7 (8.93-9.04 Mbp), identified the candidate gene , where cultivars with a deletion upstream of the gene had higher concentrations of cadmium compared to the cultivars that did not have the deletion. The distribution of alleles within the BAAP suggest this QTL is easily detected in this population because it is composed of cultivars. Local genome cluster analysis suggest high Cd alleles are uncommon, but should be avoided in breeding.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at (10.1007/s10681-020-02752-1).
PubMed: 33627887
DOI: 10.1007/s10681-020-02752-1 -
Seminars in Cell & Developmental Biology Apr 2021Sphingolipids are complex lipids. They play a structural role in neurons, but are also involved in regulating cellular communication, and neuronal differentiation and... (Review)
Review
Sphingolipids are complex lipids. They play a structural role in neurons, but are also involved in regulating cellular communication, and neuronal differentiation and maturation. There is increasing evidence to suggest that dysregulated metabolism of sphingolipids is linked to neurodegenerative processes in amyotrophic lateral sclerosis (ALS), Parkinson's disease and Gaucher's disease. In this review, we provide an overview of the role of sphingolipids in the development and maintenance of the nervous system. We describe the implications of altered metabolism of sphingolipids in the pathophysiology of certain neurodegenerative diseases, with a primary focus on ALS. Finally, we provide an update of potential treatments that could be used to target the metabolism of sphingolipids in neurodegenerative diseases.
Topics: Amyotrophic Lateral Sclerosis; Central Nervous System; Humans; Lipid Metabolism; Neurodegenerative Diseases; Sphingolipids
PubMed: 33160824
DOI: 10.1016/j.semcdb.2020.10.008 -
British Journal of Clinical Pharmacology Aug 2017The Neuroscience-based Nomenclature (NbN) for psychotropic drugs was developed as an alternative to the current Anatomical Therapeutic Chemical (ATC) indication-based...
The Neuroscience-based Nomenclature (NbN) for psychotropic drugs was developed as an alternative to the current Anatomical Therapeutic Chemical (ATC) indication-based classification in order to provide more precise designations for this drug class. The ATC nomenclature for psychotherapeutics is limited in that it fails to specify either pharmacological domains or mechanism of action and also does not describe all the potential uses of a particular agent. The disconnect between the drug classification and its clinical use is not very useful for scientific purposes and is confusing for patients and caregivers, often leading to a misunderstanding of the intended effects of the prescribed medication and, most importantly, to low treatment adherence. The NbN classifies psychopharmacological agents on the basis of contemporary scientific information on their pharmacology and mechanisms of action so as to provide physicians clear alternatives when selecting or altering therapeutic regimens. The classification of each psychotropic drug includes four additional dimensions: approved indications; efficacy and side effects; practical note; neurobiology. By emphasizing the pharmacology and the molecular mechanism of action, NbN provides a vehicle for clinicians and basic scientists to improve the understanding and clinical use of this important drug class.
Topics: Anatomy; Humans; Mental Disorders; Neurosciences; Psychotropic Drugs; Terminology as Topic
PubMed: 28401576
DOI: 10.1111/bcp.13302