ELUCIDATING PEATLAND DISTURBANCE ECOLOGY AND CARBON DYNAMICS THROUGH THE LENS OF SOIL USING INFRARED SPECTROMETRY

We sought to quantify the fire regimes of peatlands in the hemi-boreal zone of North America, and to understand the qualities of their peat. We used infrared spectrometry to accomplish both goals by gathering spectral information about the organic matter in each sample. We used a series of mixtures of natural peat and natural peat charcoal to isolate the spectral components associated with charcoal concentration. We built a multiple linear regression model which predicts the charcoal concentration in peat samples. We validated our data using nuclear magnetic resonance spectrometry. As a result, we can accurately predict the charcoal concentration of peat samples using only their infrared spectra. Applying this method, we analyzed the charcoal concentration throughout the peat profile in 29 sites in the hemi-boreal region of North America. These sites fell into four peatland ecotypes common in the hemi-boreal region, three types of poor fens, differing by tree cover, and forested rich fens. We found that the poor fen ecotypes had a mean fire return interval of 480 years, while the forested rich fens usually had no evidence of fire. We also found that fire frequency was negatively correlated with carbon accumulation in the poor fen ecotypes. These findings indicate that fire is a normal part of poor fen ecosystems but is rare in forested rich fens. Significant changes to these norms could have deleterious consequences for these ecosystems. We also performed analyses to compare the peat quality of these same ecotypes to one another. Peat quality refers to molecular lability. We were able to consider peat quality throughout each core. We identified that forested peatlands had more consistent, lower peat quality than open fens, which had high quality surface peat that declined in quality rapidly. Overall open poor fens had the highest peat quality, followed by forested poor fens, and finally forested rich fens. This implies that open poor fens are more vulnerable to both short- and long-term disturbances to temperature or water levels. Our research contributes knowledge that equips ecologists, managers, and policy makers to better understand, plan for, and conserve peatlands in our changing world

Modulation of Pain by Endocannabinoids in the Periphery

Activation of cannabinoid receptors using systemic treatments produces analgesia in a variety of experimental pain models, but these effects are hindered by sedation and motor impairment mediated by receptors in the central nervous system. Targeting the endocannabinoid system in the periphery can bypass these unwanted side effects while still producing analgesia in both acute and chronic pain states. This chapter discusses the different approaches to increasing peripheral endocannabinoid activity in experimental models of acute and chronic pain, including inflammatory pain, neuropathic pain, and sickle cell disease. We also explore how these treatments alter nociceptive activity in the peripheral nervous system

Cisplatin and the Mu Opioid Receptor Antagonist Methylnaltrexone Inhibit Neurite Growth in Cultured Trigeminal Neurons

https://openworks.mdanderson.org/sumexp23/1040/thumbnail.jp

ApoA-I binding protein (AIBP) decreases mechanical hypersensitivity after plantar incision in a rat model of post-operative pain

https://openworks.mdanderson.org/sumexp22/1090/thumbnail.jp

Developmental alterations in noxious-evoked EEG activity recorded from rat primary somatosensory cortex

Primary somatosensory cortex (S1) contains a nociceptive map that localizes potential tissue damage on the body and encodes stimulus intensity. An objective and specific biomarker of pain however is currently lacking and is urgently required for use in non-verbal clinical populations as well as in the validation of pre-clinical pain models. Here we describe studies to see if the responses of the S1 in juvenile rats are different to those in the adult. We recorded electroencephalogram (EEG) responses from S1 of lightly-anesthetized Sprague–Dawley rats at either postnatal day 21 or postnatal day 40 during the presentation of noxious (55 °C) or innocuous (30 °C) thermal stimuli applied to the plantar surface of the left hindpaw. The total EEG power across the recording period was the same in both ages after stimulation but the frequency distribution was significantly affected by age. Noxious heat evoked a significant increase in theta band (4–8 Hz) activity in adults only (P < 0.0001 compared to baseline; P < 0.0001 compared to juveniles). There were no significant differences in EEG responses to innocuous thermal stimuli. These data show that there are significant alterations in the processing of nociceptive inputs within the maturing cortex and that cortical theta activity is involved only in the adult cortical response to noxious stimulation

Cancer chemotherapy in early life significantly alters the maturation of pain processing

Advances in paediatric cancer treatment have led to a ten year survival rate greater than 75%. Platinum-based chemotherapies (e.g.cisplatin) induce peripheral sensory neuropathy in adult and paedriatric cancer patients. The period from birth through to adulthood represents a period of maturation within nociceptive systems. Here we investigated how cisplatin impacts upon postnatal maturation of nociceptive systems. Neonatal Wistar rats (Postnatal day (P) 7) were injected (i.p.) daily with either vehicle (PBS) or cisplatin (1mg/kg) for five consecutive days. Neither group developed mechanical or thermal hypersensitivity immediately during or after treatment. At P22 the cisplatin group developed mechanical (P<0.05) and thermal (P<0.0001) hypersensitivity versus vehicle group. Total DRG or dorsal horn neuronal number did not differ at P45, however there was an increase in intraepidermal nerve fibre density in cisplatin treated animals at this age. The percentage of IB4+ve, CGRP+ve and NF200+ve DRG neurons was not different between groups at P45. There was an increase in TrkA+ve DRG neurons in the cisplatin group at P45, in addition to increased TrkA, NF200 and vGLUT2 immunoreactivity in the lumbar dorsal horn versus controls. These data highlight the impact paediatric cancer chemotherapy has upon the maturation of pain pathways and later life pain experience

Psychophysical Investigations into the Role of Low-Threshold C Fibres in Non-Painful Affective Processing and Pain Modulation

We recently showed that C low-threshold mechanoreceptors (CLTMRs) contribute to touch-evoked pain (allodynia) during experimental muscle pain. Conversely, in absence of ongoing pain, the activation of CLTMRs has been shown to correlate with a diffuse sensation of pleasant touch. In this study, we evaluated (1) the primary afferent fibre types contributing to positive (pleasant) and negative (unpleasant) affective touch and (2) the effects of tactile stimuli on tonic muscle pain by varying affective attributes and frequency parameters. Psychophysical observations were made in 10 healthy participants. Two types of test stimuli were applied: stroking stimulus using velvet or sandpaper at speeds of 0.1, 1.0 and 10.0 cm/s; focal vibrotactile stimulus at low (20 Hz) or high (200 Hz) frequency. These stimuli were applied in the normal condition (i.e. no experimental pain) and following the induction of muscle pain by infusing hypertonic saline (5%) into the tibialis anterior muscle. These observations were repeated following the conduction block of myelinated fibres by compression of sciatic nerve. In absence of muscle pain, all participants reliably linked velvet-stroking to pleasantness and sandpaper-stroking to unpleasantness (no pain). Likewise, low-frequency vibration was linked to pleasantness and high-frequency vibration to unpleasantness. During muscle pain, the application of previously pleasant stimuli resulted in overall pain relief, whereas the application of previously unpleasant stimuli resulted in overall pain intensification. These effects were significant, reproducible and persisted following the blockade of myelinated fibres. Taken together, these findings suggest the role of low-threshold C fibres in affective and pain processing. Furthermore, these observations suggest that temporal coding need not be limited to discriminative aspects of tactile processing, but may contribute to affective attributes, which in turn predispose individual responses towards excitatory or inhibitory modulation of pain

A língua inglesa como marca da pós-modernidade: considerações sobre seu uso comercial em Joinville

This paper has the objective of studying the use of the English language to name commercial organizations in Joinville, state of Santa Catarina Brazil, considering the notion of postmodernity, and using as an analysis device the Peircean semiotics. Taking into account the ideas of Fredric Jameson, Jean-François Lyotard and Stuart Hall, I regard as postmodern elements: the loss of cultural identity, the disbelief in ancestors tradition, and the capitalism allied with globalization. Therefore, I relate these elements to the occurrence of the linguistic phenomenon that I study here. The city context shows a cultural fragmentation that can be understood, considering the rupture in relation to the German culture, inherited from the immigrants, and associating it with the contact to other cultures, because of the constant migration. The corpus analyzed was a set of streets that are situated in the central area of the city, and some neighborhoods. It includes a considerable number of businesses, so it was possible to have a significant figure, in terms of percentage. This analysis made use of semiotics to categorize the signs, according to the trichotomic Peircean classification and, it identified: icons, indexes and symbols. The conclusion of this paper is that, the commercial use of the English language in this community refers more to the visual context, than to the linguistic one, so it does not indicate that the foreign language has being used as means of communication to the detriment of the Portuguese language.Este trabalho tem por objetivo estudar o uso da língua inglesa nas denominações dos estabelecimentos comerciais da cidade de Joinville, Santa Catarina, Brasil, a partir da noção de pós-modernidade e, utilizando como instrumento de análise, a semiótica peirceana. A partir de Frederic Jameson, Jean-François Lyotard e Stuart Hall considero como elementos da pós-modernidade, a perda da identidade cultural, o descrédito pelas tradições dos antepassados e o capitalismo aliado à globalização. Relaciono esses elementos à ocorrência do fenômeno lingüístico que estudo aqui. O contexto joinvilense apresenta uma fragmentação cultural que, através de um resgate histórico, foi possível entender, tendo em vista a ocorrência de uma ruptura em relação à cultura alemã, herdada dos colonizadores, associada à exposição a outras culturas advindas da constante migração. O corpus selecionado, um conjunto de ruas que compreende a região central da cidade e alguns bairros adjacentes, agrega um número considerável de estabelecimentos comerciais, o que permitiu uma amostragem significativa em termos percentuais. É apresentada uma análise semiótica dos signos que utilizam a língua inglesa, segundo a classificação tricotômica peirceana, de tal forma a identificar ícones, índices e símbolos. A conclusão do trabalho é que o uso comercial da língua inglesa na comunidade joinvilense tem um comprometimento mais visual do que lingüístico, sendo assim, ele não é um indício de que a língua estrangeira está sendo usada como meio de comunicação, em detrimento da língua portuguesa.Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Fire History and Long-term Carbon Accumulation in Hemi-boreal Peatlands Companion Dataset

This dataset contains peat property data including location, depth, bulk density, organic matter content, and carbon content, infrared spectra, and radiocarbon dates. Peat cores were collected between 2011 and 2019. Analyses were performed between 2018 and 2021. Samples were collected from peatlands in Michigan, Wisconsin, and Minnesota for the purposes of reconstruction of fire history. The data is associated with a yet-to-be-published manuscript to be submitted to Ecosystems. A README file is included describing the contents of the dataset and all major spreadsheet files contain a Meta worksheet which describes each column ofdata