The evolution of the marine carbonate factory.

Calcium carbonate formation is the primary pathway by which carbon is returned from the ocean-atmosphere system to the solid Earth1,2. The removal of dissolved inorganic carbon from seawater by precipitation of carbonate minerals-the marine carbonate factory-plays a critical role in shaping marine biogeochemical cycling1,2. A paucity of empirical constraints has led to widely divergent views on how the marine carbonate factory has changed over time3-5. Here we use geochemical insights from stable strontium isotopes to provide a new perspective on the evolution of the marine carbonate factory and carbonate mineral saturation states. Although the production of carbonates in the surface ocean and in shallow seafloor settings have been widely considered the predominant carbonate sinks for most of the history of the Earth6, we propose that alternative processes-such as porewater production of authigenic carbonates-may have represented a major carbonate sink throughout the Precambrian. Our results also suggest that the rise of the skeletal carbonate factory decreased seawater carbonate saturation states.

Microbial biogeography of the eastern Yucatán carbonate aquifer.

IMPORTANCE: The extensive Yucatán carbonate aquifer, located primarily in southeastern Mexico, is pockmarked by numerous sinkholes (cenotes) that lead to a complex web of underwater caves. The aquifer hosts a diverse yet understudied microbiome throughout its highly stratified water column, which is marked by a meteoric lens floating on intruding seawater owing to the coastal proximity and high permeability of the Yucatán carbonate platform. Here, we present a biogeographic survey of bacterial and archaeal communities from the eastern Yucatán aquifer. We apply a novel network analysis software that models ecological niche space from microbial taxonomic abundance data. Our analysis reveals that the aquifer community is composed of several distinct niches that follow broader regional and hydrological patterns. This work lays the groundwork for future investigations to characterize the biogeochemical potential of the entire aquifer with other systems biology approaches.

Global human influence maps reveal clear opportunities in conserving Earth's remaining intact terrestrial ecosystems.

Leading up to the Convention on Biological Diversity Conference of the Parties 15, there is momentum around setting bold conservation targets. Yet, it remains unclear how much of Earth's land area remains without significant human influence and where this land is located. We compare four recent global maps of human influences across Earth's land, Anthromes, Global Human Modification, Human Footprint and Low Impact Areas, to answer these questions. Despite using various methodologies and data, these different spatial assessments independently estimate similar percentages of the Earth's terrestrial surface as having very low (20%-34%) and low (48%-56%) human influence. Three out of four spatial assessments agree on 46% of the non-permanent ice- or snow-covered land as having low human influence. However, much of the very low and low influence portions of the planet are comprised of cold (e.g., boreal forests, montane grasslands and tundra) or arid (e.g., deserts) landscapes. Only four biomes (boreal forests, deserts, temperate coniferous forests and tundra) have a majority of datasets agreeing that at least half of their area has very low human influence. More concerning, <1% of temperate grasslands, tropical coniferous forests and tropical dry forests have very low human influence across most datasets, and tropical grasslands, mangroves and montane grasslands also have <1% of land identified as very low influence across all datasets. These findings suggest that about half of Earth's terrestrial surface has relatively low human influence and offers opportunities for proactive conservation actions to retain the last intact ecosystems on the planet. However, though the relative abundance of ecosystem areas with low human influence varies widely by biome, conserving these last intact areas should be a high priority before they are completely lost.

The global decline of cheetah Acinonyx jubatus and what it means for conservation.

Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human-wildlife coexistence across large multiple-use landscapes.

Quantifying the Impact of Atmospheric Transport Uncertainty on CO2 Surface Flux Estimates.

We show that transport differences between two commonly used global chemical transport models, GEOS-Chem and TM5, lead to systematic space-time differences in modeled distributions of carbon dioxide and sulfur hexafluoride. The distribution of differences suggests inconsistencies between the transport simulated by the models, most likely due to the representation of vertical motion. We further demonstrate that these transport differences result in systematic differences in surface CO2 flux estimated by a collection of global atmospheric inverse models using TM5 and GEOS-Chem and constrained by in situ and satellite observations. While the impact on inferred surface fluxes is most easily illustrated in the magnitude of the seasonal cycle of surface CO2 exchange, it is the annual carbon budgets that are particularly relevant for carbon cycle science and policy. We show that inverse model flux estimates for large zonal bands can have systematic biases of up to 1.7 PgC/year due to large-scale transport uncertainty. These uncertainties will propagate directly into analysis of the annual meridional CO2 flux gradient between the tropics and northern midlatitudes, a key metric for understanding the location, and more importantly the processes, responsible for the annual global carbon sink. The research suggests that variability among transport models remains the largest source of uncertainty across global flux inversion systems and highlights the importance both of using model ensembles and of using independent constraints to evaluate simulated transport.

Evaluation of natural goethite on the removal of arsenate and selenite from water.

Elevated arsenic and selenium concentrations in water cause health problems to both humans and wildlife. Natural and anthropogenic activities have caused contamination of these elements in waters worldwide, making the development of efficient cost-effective methods in their removal essential. In this work, removal of arsenate and selenite from water by adsorption onto a natural goethite (α-FeOOH) sample was studied at varying conditions. The data was then compared with other arsenate, selenite/goethite adsorption systems as much of literature shows discrepancies due to varying adsorption conditions. Characterization of the goethite was completed using inductively coupled plasma mass spectrometry, X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and Brunauer-Emmett-Teller surface area analysis. Pseudo-first order (PFO) and pseudo-second order (PSO) kinetic models were applied; including comparisons of different regression methods. Various adsorption isotherm models were applied to determine the best fitting model and to compare adsorption capacitates with other works. Desorption/leaching of arsenate and selenite was studied though the addition of phosphate and hydroxyl ions. Langmuir isotherm modeling resulted in maximum adsorption capacities of 6.204 and 7.740 mg/g for arsenate and selenite adsorption, respectively. The PSO model applied with a non-linear regression resulted in the best kinetic fits for both adsorption and desorption of arsenate and selenite. Adsorption decreased with increasing pH. Phosphate induced desorption resulted in the highest percentage of arsenate and selenite desorbed, while hydroxide induced resulted in the fastest desorption kinetics.

Feasibility of Using Bluetooth Low Energy Beacon Sensors to Detect Magnifier Usage by Low Vision Patients.

SIGNIFICANCE: We demonstrated proof of concept for the potential for Bluetooth low energy beacons to reliably collect data to serve as an indicator that low vision patients are using handheld magnifiers for reading, which might be used in the future to prevent the abandonment of magnification or other assistive devices. PURPOSE: Bluetooth low energy beacons are an emerging novel technology involving tiny sensors that collect real-time, continuous, objective data, which might help to ascertain the abandonment of low vision devices in a timely manner, thus prompting a follow-up evaluation to attempt to resolve issues. We evaluated whether Bluetooth beacon data could indicate when low vision patients used handheld optical magnifiers for reading. METHODS: We recorded temperature and/or relative humidity data from Estimote sticker and BlueMaestro Tempo Disc beacons attached to handles of optical magnifiers used for reading by low vision patients in clinic (n = 16) and at home (n = 3). RESULTS: In the clinic, patients whose hand/fingers made direct versus indirect contact with Estimote beacons had greater temperature increases on average from baseline after 30 seconds (0.73°C vs. 0.28°C), 60 seconds (1.04°C vs. 0.40°C), 90 seconds (1.39°C vs. 0.60°C), 105 to 120 seconds (1.59°C vs. 0.62°C), and 135 to 150 seconds (2.07°C vs. 0.97°C). During magnifier usage at home, BlueMaestro beacons measured rapidly increased temperature (5.6°C per minute on average; range 2.7 to 7.3°C) and relative humidity (19.4% per minute on average; range 8.7 to 34%). Humidity tended to reach its maximum increase and return back to baseline significantly more quickly than temperature (P = .007). All increases during magnifier usage were much greater than the maximum room fluctuations without use (clinic, 0.2°C over 120 seconds; home, 0.6°C and 2.4% over 1 minute). The beacons were nonintrusive and acceptable by patients. CONCLUSIONS: Estimote and BlueMaestro beacons can reliably detect temperature and/or humidity increases when held by low vision patients while reading with a magnifier.

Functions of the 19S complex in proteasomal degradation.

The 26S proteasome degrades ubiquitylated proteins. It consists of the 20S proteasome and the PA700/19S complex. PA700 plays essential roles in processing ubiquitylated substrates; it can bind, deubiquitylate, and unfold ubiquitylated proteins, which then translocate into the proteolytic chamber of the 20S proteasome for degradation. Here, we summarize the current knowledge of PA700-mediated substrate binding and deubiquitylation, and provide models to explain how substrate binding and deubiquitylation could regulate proteasomal degradation. We also discuss the features and potential therapeutic uses of the two recently identified small molecule inhibitors of the proteasome-residing deubiquitylating enzymes.

Relative effectiveness of selected preenrichment media for the detection of Salmonella from leafy green produce and herbs.

Four buffered preenrichment media (BAX® System MP Media (BAX)), Universal Preenrichment Broth (UPB), modified Buffered Peptone Water (mBPW), and Buffered Peptone Water (BPW)) were compared with lactose broth (LB) in the Bacteriological Analytical Manual's (BAM) Salmonella culture method for the analysis of 9 leafy green produce and herb types. Artificially contaminated test portions were pre-enriched in each medium and the results were analyzed statistically using Fisher's Exact 2-tailed F test (p < 0.05) with pairwise comparisons. There was no difference in recovery of Salmonella from curly parsley and basil among the five media (p > 0.05). UPB was consistently among the most effective media for recovery of Salmonella from the nine produce types; however, S. Typhimurium and S. Newport were isolated from cabbage more frequently with mBPW than with UPB (p < 0.05). Comparisons of the results among the preenrichment media from all experimental trials, with leafy green produce and herbs, demonstrate that Salmonella is more effectively detected and isolated using buffered enrichments than with the currently recommended LB (p < 0.05). There were no significant differences among the buffered preenrichments for the detection of Salmonella-positive test portions of the produce tested (BAX (160 Salmonella-positive test portions/480 test portions), UPB (176/480), mBPW (184/480), BPW (169/480), LB (128/480))(p > 0.05).

Evaluation and comparison of rapid methods for the detection of Salmonella in naturally contaminated pine nuts using different pre enrichment media.

Foodborne outbreaks, involving pine nuts and peanut butter, illustrate the need to rapidly detect Salmonella in low moisture foods. However, the current Bacteriological Analytical Manual (BAM) culture method for Salmonella, using lactose broth (LB) as a pre enrichment medium, has not reliably supported real-time quantitative PCR (qPCR) assays for certain foods. We evaluated two qPCR assays in LB and four other pre enrichment media: buffered peptone water (BPW), modified BPW (mBPW), Universal Pre enrichment broth (UPB), and BAX(®) MP media to detect Salmonella in naturally-contaminated pine nuts (2011 outbreak). A four-way comparison among culture method, Pathatrix(®) Auto, VIDAS(®) Easy SLM, and qPCR was conducted. Automated DNA extraction techniques were compared with manual extraction methods (boiling or InstaGene™). There were no significant differences (P > 0.05) among the five pre enrichment media for pine nuts using the culture method. While both qPCR assays produced significantly (P ≤ 0.05) higher false negatives in 24 h pre enriched LB than in the other four media, they were as sensitive as the culture method in BPW, mBPW, UPB, and BAX media. The VIDAS Easy and qPCR were equivalent; Pathatrix was the least effective method. The Automatic PrepSEQ™ DNA extraction, using 1000 µL of pre enrichment, was as effective as manual extraction methods.

Technical Note: Calcium and carbon stable isotope ratios as paleodietary indicators.

Calcium stable isotope ratios are hypothesized to vary as a function of trophic level. This premise raises the possibility of using calcium stable isotope ratios to study the dietary behaviors of fossil taxa and to test competing hypotheses on the adaptive origins of euprimates. To explore this concept, we measured the stable isotope composition of contemporary mammals in northern Borneo and northwestern Costa Rica, two communities with functional or phylogenetic relevance to primate origins. We found that bone collagen δ(13) C and δ(15) N values could differentiate trophic levels in each assemblage, a result that justifies the use of these systems to test the predicted inverse relationship between bioapatite δ(13) C and δ(44) Ca values. As expected, taxonomic carnivores (felids) showed a combination of high δ(13) C and low δ(44) Ca values; however, the δ(44) Ca values of other faunivores were indistinguishable from those of primary consumers. We suggest that the trophic insensitivity of most bioapatite δ(44) Ca values is attributable to the negligible calcium content of arthropod prey. Although the present results are inconclusive, the tandem analysis of δ(44) Ca and δ(13) C values in fossils continues to hold promise for informing paleodietary studies and we highlight this potential by drawing attention to the stable isotope composition of the Early Eocene primate Cantius.

Mechanisms of Hysteresis and Reversibility across the Voltage-Driven Perovskite-Brownmillerite Transformation in Electrolyte-Gated Ultrathin La0.5Sr0.5CoO3-δ.

Perovskite cobaltites have emerged as archetypes for electrochemical control of materials properties in electrolyte-gate devices. Voltage-driven redox cycling can be performed between fully oxygenated perovskite and oxygen-vacancy-ordered brownmillerite phases, enabling exceptional modulation of the crystal structure, electronic transport, thermal transport, magnetism, and optical properties. The vast majority of studies, however, have focused heavily on the perovskite and brownmillerite end points. In contrast, here we focus on hysteresis and reversibility across the entire perovskite ↔ brownmillerite topotactic transformation, combining gate-voltage hysteresis loops, minor hysteresis loops, quantitative operando synchrotron X-ray diffraction, and temperature-dependent (magneto)transport, on ion-gel-gated ultrathin (10-unit-cell) epitaxial La0.5Sr0.5CoO3-δ films. Gate-voltage hysteresis loops combined with operando diffraction reveal a wealth of new mechanistic findings, including asymmetric redox kinetics due to differing oxygen diffusivities in the two phases, nonmonotonic transformation rates due to the first-order nature of the transformation, and limits on reversibility due to first-cycle structural degradation. Minor loops additionally enable the first rational design of an optimal gate-voltage cycle. Combining this knowledge, we demonstrate state-of-the-art nonvolatile cycling of electronic and magnetic properties, encompassing >105 transport ON/OFF ratios at room temperature, and reversible metal-insulator-metal and ferromagnet-nonferromagnet-ferromagnet cycling, all at 10-unit-cell thickness with high room-temperature stability. This paves the way for future work to establish the ultimate cycling frequency and endurance of such devices.

Hereditary Creutzfeldt-Jakob Disease: A Case Presentation of a Rare Stroke Mimic.

Acute ischemic cerebrovascular accident (CVA) is a time-sensitive emergent diagnosis, requiring rapid diagnosis and consideration of thrombolytic administration. However, a myriad of cerebrovascular mimics creates a diagnostic challenge. A rare CVA mimic is Creutzfeldt-Jakob disease (CJD), a rapidly progressive fatal dementia due to protein misfolding. Magnetic resonance imaging (MRI) and neurology consultation for electroencephalogram (EEG) and specialized cerebrospinal fluid (CSF) studies are diagnostic while the patient is alive. All forms are fatal within months, and diagnosis can be confirmed on postmortem brain testing. While incredibly uncommon, emergency clinicians should consider this diagnosis in the proper patient to advocate for specialized CSF testing and potential palliative care consultation.

Incidence of Surgically Managed Post-Tonsillectomy Hemorrhage Associated With NSAID Prescribing for Postoperative Pain Management.

INTRODUCTION: Tonsillectomy ranks high among the most common pediatric surgical procedures in the United States. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), such as ibuprofen, are routinely prescribed to manage post-tonsillectomy pain, but may carry the risk of hemorrhage. MATERIALS AND METHODS: This retrospective, longitudinal, secondary-data analysis study compared the incidence of surgically managed post-tonsillectomy hemorrhage (sPTH) in pediatric patients prescribed ibuprofen at Brooke Army Medical Center (BAMC) after tonsillectomy compared to a similar cohort of pediatric patients at the Children's Hospital of Philadelphia (CHOP) not prescribed ibuprofen. Additional regression analysis examined predictors of sPTH at BAMC. RESULTS: The odds of sPTH was lower in patients who were prescribed ibuprofen at BAMC, relative to patients who were not at CHOP (OR 0.57, 95% CI, 0.37, 0.87; P < 0.01). In a generalized linear model evaluating BAMC patient data, there was a lack of a relationship between reason for tonsillectomy (tonsillitis versus tonsillar obstruction), primary procedure (tonsillectomy-only versus tonsillectomy with adenoidectomy), and presence of a co-occurring procedure. CONCLUSIONS: Post-tonsillectomy ibuprofen prescribing practices were not associated with an elevated risk of sPTH, relative to patients at CHOP not exposed to ibuprofen.

A large proportion of North American net ecosystem production is offset by emissions from harvested products, river/stream evasion, and biomass burning.

Diagnostic carbon cycle models produce estimates of net ecosystem production (NEP, the balance of net primary production and heterotrophic respiration) by integrating information from (i) satellite-based observations of land surface vegetation characteristics; (ii) distributed meteorological data; and (iii) eddy covariance flux tower observations of net ecosystem exchange (NEE) (used in model parameterization). However, a full bottom-up accounting of NEE (the vertical carbon flux) that is suitable for integration with atmosphere-based inversion modeling also includes emissions from decomposition/respiration of harvested forest and agricultural products, CO2 evasion from streams and rivers, and biomass burning. Here, we produce a daily time step NEE for North America for the year 2004 that includes NEP as well as the additional emissions. This NEE product was run in the forward mode through the CarbonTracker inversion setup to evaluate its consistency with CO2 concentration observations. The year 2004 was climatologically favorable for NEP over North America and the continental total was estimated at 1730 ± 370 TgC yr(-1) (a carbon sink). Harvested product emissions (316 ± 80 TgC yr(-1) ), river/stream evasion (158 ± 50 TgC yr(-1) ), and fire emissions (142 ± 45 TgC yr(-1) ) counteracted a large proportion (35%) of the NEP sink. Geographic areas with strong carbon sinks included Midwest US croplands, and forested regions of the Northeast, Southeast, and Pacific Northwest. The forward mode run with CarbonTracker produced good agreement between observed and simulated wintertime CO2 concentrations aggregated over eight measurement sites around North America, but overestimates of summertime concentrations that suggested an underestimation of summertime carbon uptake. As terrestrial NEP is the dominant offset to fossil fuel emission over North America, a good understanding of its spatial and temporal variation - as well as the fate of the carbon it sequesters ─ is needed for a comprehensive view of the carbon cycle.

An Uncommon Case of Acute Coronary Stent Thrombosis.

Coronary stent thrombosis is an uncommon complication of percutaneous coronary intervention, which can result in myocardial infarction and often death. We present a case of acute stent thrombosis in a patient with newly diagnosed triple vessel coronary artery disease occurring within less than an hour of stent placement along with a review of the literature.

Implementation of an Un-Pairing Passport to Improve the Transition From Intern to Resident During a Critical Period of Anesthesiology Residency Training.

Background: The transition from intern year to the first year of clinical anesthesiology residency (CA-1) is a challenging period for residents and their supervisors. Orientation methods and instructional material targeting this transition vary across U.S. residency programs. An un-pairing passport was implemented during the 2021-2022 transition to guide and provide expectations for interns, senior residents, and staff. The objective of this quality improvement project was to assess the effectiveness of the passport in improving the transition period and overall preparedness of the new CA-1s. Methods: We surveyed 3 groups (CA-1s, CA-2s/CA-3s, and staff anesthesiologists) 6 months after the completion of passport implementation to retrospectively assess the 2021-2022 CA-1 class's preparedness across 7 domains compared with those who transitioned before passport implementation. Mann-Whitney U statistics and median effect sizes were used to compare pre- and postintervention. Results: Self-reflected preparedness scores of the CA-1s were higher across all domains compared with the senior resident group (r = 0.328-0.548). Overall level of comfort and preparedness for the start of the CA-1 year was higher in the postintervention group (r = 0.162- 0.514). Staff anesthesiologists' perceived preparedness of the residents was also higher across all domains for the postintervention group (r = 0.197-0.387). Conclusion: The un-pairing passport improved residents' and staff anesthesiologists' subjective assessments of the readiness of new CA-1 residents after a critical transition in their training. Similar tools can be more broadly applied to other anesthesiology residency and possibly fellowship programs as well as subspecialty rotations within those programs.

Effect of Topical Platelet Extract Daily Serum as a Cosmetic Product to Reduce Facial Redness.

Objective: The primary objective of this pilot study was to demonstrate the benefits of topical human platelet extract (plated)™ serum for the improvement of persistent facial redness. Methods: This single-center, open-label pilot study evaluated six subjects using (plated)™ serum containing human platelet extract (HPE) with Renewosome™ technology twice daily for six weeks. The primary efficacy endpoint was a reduction in the Clinical Erythema Assessment (CEA) grade, and a reduction in Patient Subjective Assessment grade at six weeks. Secondary endpoints included an improvement in quality of life related to facial redness, and a reduction in redness by Mexameter™ spectrometry measurement. Safety data included monitoring for adverse events. Results: Topical HPE serum demonstrated a statistically significant improvement in facial redness at Week 9 when averaging the Mexameter™ spectrometry results across nine regions of the face (p=0.0052). The primary and secondary endpoints were achieved. CEA grade at Week 6 demonstrated that all subjects improved by at least one grade, while one subject improved by two grades. One patient reported dryness. No other adverse effects were observed. Limitations: Study limitations included a small sample size and lack of darker skin types (Fitzpatrick IV-VI). Conclusion: This study demonstrates that topical HPE with Renewosome™ technology provides statistically significant reduction in facial redness and is safe and well-tolerated.