This paper undertakes a new materialist reading of the corpus of Anglophone poetry originating from India’s Northeastern states by instrumentalizing the experience of the sublime as a cultural ...technique that endorses the operations of its surrounding human-nonhuman network. A close reading of the corpus of poetry from India’s Northeast reflects the “material turn” in the discourse of humanities scholarship that involves other interrelated discourses such as feminism, ecocriticism, posthumanism, and material culture studies etc. Human intervention in the landscape producing the experience of the revised sublime disrupts the set distinctions and explores the unfolding of a more-than-human world which provides a larger space for reinventing the narratives. The inhabitants of this region feel a connection between the changes seen in their natural surroundings and their half-forgotten history of ethnic identities. The corpus problematises the concept of extinction by revealing several paradoxical patterns of human existences therein. The concluding part reflects on the affect produced from the experiences of the revised sublime in reconstructing the relationships between humans, nature and the material world. Through the lens of new materialism, this essay will explore how these paradoxical matrices posit the notion of the ‘revised sublime’ and affect at the centre of discussion that nullifies the distinction between organic and inorganic matters and manifests agentic capabilities within inorganic matters.
•Fe speciation in redox-stratified peats is reported.•Fe2+ and Fe3+ co-occur irrespective of redox conditions.•Complexation of Fe with organic matter is the primary stabilization mechanism.•Fe ...(oxy)hydroxide is identified as a secondary Fe species.
The speciation of iron (Fe) in organic matter (OM)-rich environments under in situ variable redox conditions is largely unresolved. Peatlands provide a natural setting to study Fe–OM interactions. Utilizing chemical, spectroscopic and theoretical modeling approaches, we report the chemical forms, oxidation states and local coordination environment of naturally occurring Fe in the vertically redox-stratified Manning peatlands of western New York. In addition, we report dominant carbon, sulfur and nitrogen species that can potentially stabilize the various Fe species present in these peatlands. Our results provide clear direct and indirect evidence for the co-occurrence of ferrous (Fe2+) and ferric (Fe3+) iron species in peats under both oxic and anoxic conditions. Iron is mostly present within the operationally defined organic and amorphous (i.e., short range ordered, SRO) fractions; ferric iron primarily as magnetically isolated paramagnetic Fe3+ in Fe(III)-organic complexes, but also in mineral forms such as ferrihydrite; ferrous iron in tetrahedral coordination in Fe(II)-organic complexes with minor contribution from pyrite. All of the Fe species identified stabilize Fe(III) and/or Fe(II) in anoxic and oxic peats. Fundamental differences are also observed in the relative proportion of C, S and N functionalities of OM in oxic and anoxic peats. Aromatic CC, ester, phenol and anomeric C (ROCOR), as well as thiol, sulfide and heterocyclic N functionalities are more prevalent in anoxic peats. Collectively, our experimental evidence suggests iron forms coordination complexes with O-, S- and N-containing functional groups of OM. We posit the co-occurrence of organic and mineral forms of Fe(II) and Fe(III) in both oxic and anoxic peat layers results from dynamic complexation and hydrolysis-precipitation reactions that occur under variable redox conditions. Our findings aid in understanding the crucial role OM plays in determining Fe species in soils and sediments.
Historically, it is believed that crystalline uraninite, produced via the abiotic reduction of hexavalent uranium (U
) is the dominant reduced U species formed in low-temperature uranium roll-front ...ore deposits. Here we show that non-crystalline U
generated through biologically mediated U
reduction is the predominant U
species in an undisturbed U roll-front ore deposit in Wyoming, USA. Characterization of U species revealed that the majority (∼58-89%) of U is bound as U
to C-containing organic functional groups or inorganic carbonate, while uraninite and U
represent only minor components. The uranium deposit exhibited mostly
U-enriched isotope signatures, consistent with largely biotic reduction of U
to U
. This finding implies that biogenic processes are more important to uranium ore genesis than previously understood. The predominance of a relatively labile form of U
also provides an opportunity for a more economical and environmentally benign mining process, as well as the design of more effective post-mining restoration strategies and human health-risk assessment.
Soil redox conditions exert substantial influence on biogeochemical processes in terrestrial ecosystems. Humid tropical forest soils are often characterized by fluctuating redox, yet how these ...dynamics affect patterns of organic matter decomposition and associated CO
2
fluxes remains poorly understood. We used a
13
C-label incubation experiment in a humid tropical forest soil to follow the decomposition of plant litter and soil organic matter (SOM) in response to four redox regimes—static oxic or anoxic, and two oscillating treatments. We used high-resolution mass spectrometry to characterize the relative composition of organic compound classes in the water extractable OM. CO
2
production from litter and SOM showed different responses to redox treatments. While cumulative production of SOM-derived CO
2
was positively correlated with the length of oxic exposure (
r
= 0.89,
n
= 20), cumulative
13
C-litter-derived CO
2
production was not linked to oxygen availability. Litter-derived CO
2
production was highest under static anoxic conditions in the first half of the experiment, and later dropped to the lowest rate amongst the treatments. In anoxic soils, we observed depletion of more oxidized water-extractable OM (especially amino sugar-, carbohydrate-, and protein-like compounds) over the second half of the experiment, which likely served as substrates for anaerobic CO
2
production. Results from two-pool kinetic modeling showed that more frequent anoxic exposure limited decomposition of a slow-cycling C pool, but not a fast-cycling pool. These results suggest that aerobic and anaerobic heterotrophs were equally effective at degrading labile substrates released from fresh plant litter in this humid tropical forest soil, while aerobic decomposers were more effective in breaking down the potentially refractory compounds found in SOM.
The traditionally held assumption that photo-dependent processes are the predominant source of H
O
in natural waters has been recently questioned by an increrasing body of evidence showing the ...ubiquitiousness of H
O
in dark water bodies and in groundwater. In this study, we conducted field measurement of H
O
in an intra-meander hyporheic zone and in surface water at East River, CO. On-site detection using a sensitive chemiluminescence method suggests H
O
concentrations in groundwater ranging from 6 nM (at the most reduced region) to ~ 80 nM (in a locally oxygen-rich area) along the intra-meander transect with a maxima of 186 nM detected in the surface water in an early afternoon, lagging the maximum solar irradiance by ∼ 1.5 h. Our results suggest that the dark profile of H
O
in the hyporheic zone is closely correlated to local redox gradients, indicating that interactions between various redox sensitive elements could play an essential role. Due to its transient nature, the widespread presence of H
O
in the hyporheic zone indicates the existence of a sustained balance between H
O
production and consumption, which potentially involves a relatively rapid succession of various biogeochemically important processes (such as organic matter turnover, metal cycling and contaminant mobilization). More importantly, this study confirmed the occurrence of reactive oxygen species at a subsurface redox transition zone and further support our understanding of redox boundaries on reactive oxygen species generation and as key locations of biogeochemical activity.
Background: Patients undergoing surgery often demonstrate coagulopathy. Usually, this derangement in coagulation is assessed by the laboratory based evaluation of blood samples. However, collection ...of samples, their transportation to the lab, and the analyses can result in several errors and as such these tests may not be representative of the complete coagulation process. In our study, we compared the lab coagulation parameters with the point of care TEG indices and attempted to compare the outcome prediction of our patients based on the TEG indices and the various practiced ICU scores.
Methods: A prospective, observational study was conducted between May 2014 and May 2015. Fifty adult patients who had undergone noncardiac surgery and had developed new onset 2 or more than 2 system involvement in the postoperative period were enrolled in the study. They were sampled simultaneously for lab coagulation parameters (PT, APTT, INR, fibrinogen, and platelet count) and TEG on days 1, 3, and 5 post admission.
Results: There were significant differences between TEG and lab coagulation parameters on day 1 of the study 1 (P = 0.004) but not on days 3 and 5. On days 1 and 3 of our study, the ICU scores (SOFA and APACHE II) were significantly higher in the group with deranged TEG parameters (P = 0.003, 0.02). The patient subpopulation with deranged TEG parameters had significantly higher mortality at median survival time (P = 0.014). Such a difference was not found in patients with higher ICU scores or deranged lab coagulation times. We constructed a ROC curve and arrived at a cutoff value of the reaction time to predict the median survival day mortality.
Conclusions: The agreement between TEG and conventional lab parameters remains poor but the TEG parameters seem to be more deranged in sicker patients. As the relationship between the overall severity of illness and derangement in the hemostatic system has been well explored in medical literature, TEG may be a more appropriate modality in such patients.
Switchgrass is a deep-rooted perennial native to the US prairies and an attractive feedstock for bioenergy production; when cultivated on marginal soils it can provide a potential mechanism to ...sequester and accumulate soil carbon (C). However, the impacts of switchgrass establishment on soil biotic/abiotic properties are poorly understood. Additionally, few studies have reported the effects of switchgrass cultivation on marginal lands that have low soil nutrient quality (N/P) or in areas that have experienced high rates of soil erosion. Here, we report a comparative analyses of soil greenhouse gases (GHG), soil chemistry, and microbial communities in two contrasting soil types (with or without switchgrass) over 17 months (1428 soil samples). These soils are highly eroded, 'Dust Bowl' remnant field sites in southern Oklahoma, USA. Our results revealed that soil C significantly increased at the sandy-loam (SL) site, but not at the clay-loam (CL) site. Significantly higher CO
flux was observed from the CL switchgrass site, along with reduced microbial diversity (both alpha and beta). Strikingly, methane (CH
) consumption was significantly reduced by an estimated 39 and 47% at the SL and CL switchgrass sites, respectively. Together, our results suggest that soil C stocks and GHG fluxes are distinctly different at highly degraded sites when switchgrass has been cultivated, implying that carbon balance considerations should be accounted for to fully evaluate the sustainability of deep-rooted perennial grass cultivation in marginal lands.
Determining the mechanisms, traits, and pathways that regulate microbial transformation of natural organic matter (NOM) is critical to informing our understanding of the microbial impacts on the ...global carbon cycle. The capillary fringe of subsurface soils is a highly dynamic environment that remains poorly understood. Characterization of organo-mineral chemistry combined with a nuanced understanding of microbial community composition and function is necessary to understand microbial impacts on NOM speciation in the capillary fringe. We present a critical review of the popular analytical and omics techniques used for characterizing complex carbon transformation by microbial communities and focus on how complementary information obtained from the different techniques enable us to connect chemical signatures with microbial genes and pathways. This holistic approach offers a way forward for the comprehensive characterization of the formation, transformation, and mineralization of terrestrial NOM as influenced by microbial communities.
Hyporheic zones act as critical ecological links between terrestrial and aquatic systems where redox-sensitive metals of iron (Fe) and manganese (Mn) significantly impact nutrient cycling and water ...quality. However, the geochemical controls on the release and speciation of Fe(II) and Mn(II) in these biogeochemical hotspots are still poorly understood. Here we conducted batch incubation experiments and analyzed Fe K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy data using sediment samples from a hyporheic zone of the East River floodplain in Colorado to understand the production, release and speciation of Fe(II) and Mn(II) in groundwater. Our results indicate that the production and release of Fe(II) and Mn(II) vary with sediment reducing conditions and subsurface positions, and the rates were determined either by a zero- or first-order rate equation. The sediments with higher Fe(II) production did not necessarily result in higher release of dissolved Fe(II), and ≥97% Fe(II) is accumulated in solid phase. We found that the majority of Fe(II) exists as siderite (FeCO
3
), Fe(II)-natural organic matter (NOM) complexes and ferrosmectite, and the equilibrium concentrations of dissolved Fe(II) are controlled primarily by siderite solubility, and enhanced greatly by formation of strong Fe(II)-NOM complexes as dominant aqueous Fe(II) species. By contract, dissolved Mn(II) increases slowly and linearly, and an equilibrium concentration was not reached during the incubation period, and the roles of rhodochrosite (MnCO
3
) and Mn(II)-NOM complexes are insignificant. Furthermore, we reviewed and calibrated the literature reported binding constants (log K) of Fe(II)-NOM complexes which successfully predicted our experimental data. This work reveals that siderite and dissolved NOM are the controlling phases in release and speciation of dissolved Fe(II), and the finding is expected to be applicable in many hyporheic zones and subsurface environments with similar geochemical conditions.
According to Barad, as claimed in Meeting the Universe Half-way: Quantum Physics and the Entanglement of Matter and Meaning, the relationships they develop intra-act with each other. Bill Brown in ...Thing Theory (2001) views theory as participating in a New Materialism triggering new thoughts about how inanimate objects constitute human subjects, how they move them, how they threaten them, how they facilitate and threaten their relations to other subjects (Brown 7). Poetry from India's Northeast echoes the spirit of ecopoems that place themselves on the cutting edge of poetic innovation and ecological thinking.2 The bond between human beings and the environment in India's Northeast bears something more than merely being smitten by the pictorial beauties of naturescape. The eighteenth-century sublime came from natural phenomena or artistic representations of natural phenomena; the unnatural disasters of the present offer no such containment within the bounds of the natural - the oil fields afire in Kuwait, the mushroom clouds above Yucca Flat, the blood-red sunsets of Los Angeles - though they still compel attention.
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