Radiative trigger thresholds of foliar photoprotective pigment regulation for global vegetation.

Adjustments in foliar photoprotective pigments are crucial for plant adaptation to harsh environments, serving as indicators of environmental stress. However, understanding when and where these adjustments occur across diverse biomes remains unclear due to challenges in large-scale observation. Here, we propose a novel approach to assess dynamics in photoprotective pigments at the canopy level using a new index derived from space-borne optical sensors. This approach generates a global map depicting the daily mean shortwave radiation threshold at which adjustments typically occur under prevailing climatic conditions. The global average of this threshold is 262 ± 50 W m⁻2, with lower values at high latitudes and peaks near 40° in both hemispheres. Temperature exerts a stronger influence on this latitudinal pattern than humidity. Future projections suggest a decrease in this threshold over northern high latitudes, implying exacerbated vulnerability under identical radiation levels due to negative warming responses. Based on this threshold, a high-stress zone around 60°N is identified and is predicted to shift southward in the future. These findings bridge critical gaps in photoprotection research and offer a new perspective on understanding the biogeochemical cycles of global ecosystems. This framework can also enhance our ability to predict the fate of diverse ecosystems under future climate.

The Arctic Plant Aboveground Biomass Synthesis Dataset.

Plant biomass is a fundamental ecosystem attribute that is sensitive to rapid climatic changes occurring in the Arctic. Nevertheless, measuring plant biomass in the Arctic is logistically challenging and resource intensive. Lack of accessible field data hinders efforts to understand the amount, composition, distribution, and changes in plant biomass in these northern ecosystems. Here, we present The Arctic plant aboveground biomass synthesis dataset, which includes field measurements of lichen, bryophyte, herb, shrub, and/or tree aboveground biomass (g m-2) on 2,327 sample plots from 636 field sites in seven countries. We created the synthesis dataset by assembling and harmonizing 32 individual datasets. Aboveground biomass was primarily quantified by harvesting sample plots during mid- to late-summer, though tree and often tall shrub biomass were quantified using surveys and allometric models. Each biomass measurement is associated with metadata including sample date, location, method, data source, and other information. This unique dataset can be leveraged to monitor, map, and model plant biomass across the rapidly warming Arctic.

A Second Look at Niacin.

Niacin is the third vitamin to be discovered and, therefore. is known as vitamin B3. It has a long history of medicinal use-nutritionally and as a skin tone brightening agent in skin care. Recent studies have suggested that niacin could be useful as an adjunctive treatment for coronavirus disease 2019 (COVID-19) and mitigating the damaging effect of blue light to the skin. Niacin, also known as nicotinic acid, nicotinamide, and niacinamide, is a physiologically active form of vitamin B3. Medicinal benefits of niacin were observed in 1902, when for the first time, patients with pellagra were treated with yeast that contained vitamin B3. Niacin has a variety of uses, particularly in treating various skin conditions, including topically as an anti-acne treatment, promoting epidermal sphingolipid synthesis, moderating photoimmunosuppression, and reducing hyperpigmentation. Niacinamide could be beneficial as an adjunctive treatment for COVID-19 and for decreasing stress if the skin is excessively exposed to blue light.

Eyes of the world on a warmer, less frozen, and greener Arctic.

Rapid atmospheric warming and sea-ice retreat are driving widespread changes in Arctic ecosystems, among the most pervasive of which is the "greening of the Arctic"-an increase in the cover and biomass of vegetation observed by satellites across much of the Arctic tundra biome. Determining the drivers, impacts, and feedbacks of Arctic greening requires continued investment in robust field, remote-sensing, and model-based capabilities, and improved integration of the knowledge base of Arctic peoples. These tools and approaches support the triangulation of complex problems and the development of improved projections for the warmer Arctic tundra biome of the future.

Leaf Functional Traits in Relation to Species Composition in an Arctic-Alpine Tundra Grassland.

The relict arctic-alpine tundra provides a natural laboratory to study the potential impacts of climate change and anthropogenic disturbance on tundra vegetation. The Nardus stricta-dominated relict tundra grasslands in the Krkonose Mountains have experienced shifting species dynamics over the past few decades. Changes in species cover of the four competing grasses-Nardus stricta, Calamagrostis villosa, Molinia caerulea, and Deschampsia cespitosa-were successfully detected using orthophotos. Leaf functional traits (anatomy/morphology, element accumulation, leaf pigments, and phenolic compound profiles), were examined in combination with in situ chlorophyll fluorescence in order to shed light on their respective spatial expansions and retreats. Our results suggest a diverse phenolic profile in combination with early leaf expansion and pigment accumulation has aided the expansion of C. villosa, while microhabitats may drive the expansion and decline of D. cespitosa in different areas of the grassland. N. stricta-the dominant species-is retreating, while M. caerulea did not demonstrate significant changes in territory between 2012 and 2018. We propose that the seasonal dynamics of pigment accumulation and canopy formation are important factors when assessing potential "spreader" species and recommend that phenology be taken into account when monitoring grass species using remote sensing.

Soil and plant-based ecosystem functions dataset of three land-use types in northwestern Virginia.

Variables that quantify nutrient cycling in terrestrial ecosystems, including aboveground and belowground biomass, litter biomass, inorganic nitrogen (NH4 + and NO3 -), and soil CO2 efflux were measured in situ. From measured variables, seasonal litter inputs and nitrogen mineralization were also estimated. Data were collected over the course of one to two growing seasons (2017 and 2018) across three different land-use types under variable human management: an agricultural field (cultivating millet for the duration of the first growing season of the study and left fallow for the duration of the second growing season), a restored native C4 tallgrass prairie, and an approximately 16-year-old successional field. The area of focus within each field was approximately 1 hectare. Five representative 5 m x 5 m plots were randomly chosen in each of the three fields. Within each 5 m x 5 m plot, three 1 m2 subplots were randomly chosen for replicate sampling. These raw data can be utilized to calculate the ecosystem functions of net nitrogen (N) mineralization, decomposition, soil respiration, aboveground primary productivity, and N leaching, which are foundational components of supporting ecosystem services in terrestrial soils and plants. These data can be used in conjunction with other datasets that describe a suite of ecosystem functions in different land-use types under variable management.

Attack on Sunscreens Continues.

The Food and Drug Administration (FDA) was required to issue and put into effect a final sunscreen monograph by November 26, 2019. On March 27, 2020, President Donald Trump signed into effect H.R. 748, the "Coronavirus Aid, Relief, and Economic Security Act" (CARES). This bill eliminated the November 2019 requirement. The CARES Act includes legislative reforms that modernize the way over-the-counter (OTC) monograph drugs are regulated in the United States. Under this Act, sunscreens will be considered generally recognized as safe and effective (GRASE), if they meet conditions newly defined by the FDA. In addition, the FDA is required to issue a proposal to revise the sun-screen requirements for GRASE not later than 18 months after enactment and will sunset by the end of the fiscal year 2022. The CARES Act also addresses the requirement for a new drug application (NDA).1-7.

The Impact of Visible Light on Skin.

Visible (VIS) light (400-700 nm), including blue light (400-500 nm), represents approximately 50% of the full optical solar spectrum. It is known since 1938 that visible light penetrates the skin. Biologic markers to fully interpret the significance of such penetration were not utilized at that time to determine the potential damage caused to the skin. The mechanisms of VIS light-induced pigmentation and melanogenesis are currently being investigated by the skin care industry.

Understanding the Effects of Optimal Combination of Spectral Bands on Deep Learning Model Predictions: A Case Study Based on Permafrost Tundra Landform Mapping Using High Resolution Multispectral Satellite Imagery.

Deep learning (DL) convolutional neural networks (CNNs) have been rapidly adapted in very high spatial resolution (VHSR) satellite image analysis. DLCNN-based computer visions (CV) applications primarily aim for everyday object detection from standard red, green, blue (RGB) imagery, while earth science remote sensing applications focus on geo object detection and classification from multispectral (MS) imagery. MS imagery includes RGB and narrow spectral channels from near- and/or middle-infrared regions of reflectance spectra. The central objective of this exploratory study is to understand to what degree MS band statistics govern DLCNN model predictions. We scaffold our analysis on a case study that uses Arctic tundra permafrost landform features called ice-wedge polygons (IWPs) as candidate geo objects. We choose Mask RCNN as the DLCNN architecture to detect IWPs from eight-band Worldview-02 VHSR satellite imagery. A systematic experiment was designed to understand the impact on choosing the optimal three-band combination in model prediction. We tasked five cohorts of three-band combinations coupled with statistical measures to gauge the spectral variability of input MS bands. The candidate scenes produced high model detection accuracies for the F1 score, ranging between 0.89 to 0.95, for two different band combinations (coastal blue, blue, green (1,2,3) and green, yellow, red (3,4,5)). The mapping workflow discerned the IWPs by exhibiting low random and systematic error in the order of 0.17-0.19 and 0.20-0.21, respectively, for band combinations (1,2,3). Results suggest that the prediction accuracy of the Mask-RCNN model is significantly influenced by the input MS bands. Overall, our findings accentuate the importance of considering the image statistics of input MS bands and careful selection of optimal bands for DLCNN predictions when DLCNN architectures are restricted to three spectral channels.

A Rare Case of Idiopathic Pyometra in a Premenopausal Patient.

Pyometra is a very uncommon disease principally occurring in postmenopausal women. It is characterized by the accumulation of purulent material within the uterine cavity. This paper presents the clinical history of a 35-year-old premenopausal woman with otherwise normal menstruation who developed heavy menstruation and was diagnosed with a benign pyometra of indeterminate etiology in March 2017. The patient underwent repeated ultrasound-guided drainage, dilation and curettage, and antibiotic therapy. Biopsies of the pelvic sidewall revealed endometriosis in June 2017. The heavy menstruation and suppurative fluid in the uterus of the patient persisted in which intramuscular leuprolide acetate was prescribed to address the endometriosis and heavy menstrual bleeding. Ultimately, the leuprolide acetate effectively resolved the patient's bleeding and pyometra. The medication was concluded after 12 months of supervision and the patient is currently symptom free. Pyometra is an unusual condition rarely identified in premenopausal women. Drainage and antibiotic therapy are routinely employed; however, one may consider gonadotropin-releasing hormone agonist medication to potentially confer a beneficial patient outcome in rare cases where endometriosis and bleeding are intractable.

Influence of Sex Ratio and Density on the Comparative Repellency of IR3535® Against Caged Aedes, Anopheles, and Culex Mosquitoes.

Studies on topical repellent efficacy conducted with caged mosquitoes in the laboratory are important to both the development and regulation of insect repellents. Guidelines for laboratory studies stipulate specific densities, sex ratios, and biting rates, whereas those for field studies are governmentally required before a promising repellent can be registered for human use. These protocols stipulate minimum biting rates alone. Relatively little is known, however, about the influence of mosquito density and sex ratio on their biting propensity, either in the field or laboratory. Using Environmental Protection Agency guidelines for cage testing, we studied the influence of mosquito density and sex ratio in laboratory repellency tests of the biopesticide Ethyl butylacetylaminopropionate (IR3535™) (20%) against three mosquito species (Aedes aegypti, Anopheles aquasalis, and Culex quinquefasciatus). DEET [3-(N-acetyl-N-butyl) aminopropionic acid ethyl ester] (20%) in a laboratory prepared formulation was used as a comparison article. Studies were conducted by trained investigators at the BioAgri Laboratories in Brazil. We found that higher mosquito density generally decreased protection time, but that the influence of sex ratio was more complex. The presence of male mosquitoes increased protection times against Aedes and Anopheles perhaps because mate-seeking males interfered with female feeding. Interestingly, by contrast, protection times decreased against Culex in the presence of males. Such considerations may potentially assist in improving the match between cage and field testing under a broader range of conditions that permit more accurate labeling of repellents for safe and effective use by consumers.

Intensified vegetation water use under acid deposition.

Despite the important role vegetation plays in the global water cycle, the exact controls of vegetation water use, especially the role of soil biogeochemistry, remain elusive. In this study, we reveal a new mechanism of soil biogeochemical control of large-scale vegetation water use. Nitrate and sulfate deposition from fossil fuel burning have caused substantial soil acidification, leading to the leaching of soil base cations. Of these, calcium has a unique role in plant cells by regulating stomatal aperture, thus affecting vegetation water use. We hypothesized that the leaching of the soil calcium supply, induced by acid deposition, would increase large-scale vegetation water use. We present evidence from a long-term whole watershed acidification experiment demonstrating that the alteration of the soil calcium supply by acid deposition can significantly intensify vegetation water use (~10% increase in evapotranspiration) and deplete available soil water. These results are critical to understanding future water availability, biogeochemical cycles, and surface energy flux and to help reduce uncertainties in terrestrial biosphere models.

Vegetation on mesic loamy and sandy soils along a 1700-km maritime Eurasia Arctic Transect.

QUESTIONS: How do plant communities on zonal loamy vs. sandy soils vary across the full maritime Arctic bioclimate gradient? How are plant communities of these areas related to existing vegetation units of the European Vegetation Classification? What are the main environmental factors controlling transitions of vegetation along the bioclimate gradient? LOCATION: 1700-km Eurasia Arctic Transect (EAT), Yamal Peninsula and Franz Josef Land (FJL), Russia. METHODS: The Braun-Blanquet approach was used to sample mesic loamy and sandy plots on 14 total study sites at six locations, one in each of the five Arctic bioclimate subzones and the forest-tundra transition. Trends in soil factors, cover of plant growth forms (PGFs) and species diversity were examined along the summer warmth index (SWI) gradient and on loamy and sandy soils. Classification and ordination were used to group the plots and to test relationships between vegetation and environmental factors. RESULTS: Clear, mostly non-linear, trends occurred for soil factors, vegetation structure and species diversity along the climate gradient. Cluster analysis revealed seven groups with clear relationships to subzone and soil texture. Clusters at the ends of the bioclimate gradient (forest-tundra and polar desert) had many highly diagnostic taxa, whereas clusters from the Yamal Peninsula had only a few. Axis 1 of a DCA was strongly correlated with latitude and summer warmth; Axis 2 was strongly correlated with soil moisture, percentage sand and landscape age. CONCLUSIONS: Summer temperature and soil texture have clear effects on tundra canopy structure and species composition, with consequences for ecosystem properties. Each layer of the plant canopy has a distinct region of peak abundance along the bioclimate gradient. The major vegetation types are weakly aligned with described classes of the European Vegetation Checklist, indicating a continuous floristic gradient rather than distinct subzone regions. The study provides ground-based vegetation data for satellite-based interpretations of the western maritime Eurasian Arctic, and the first vegetation data from Hayes Island, Franz Josef Land, which is strongly separated geographically and floristically from the rest of the gradient and most susceptible to on-going climate change.

Selected Case From the Arkadi M. Rywlin International Pathology Slide Seminar: Atypical Thymoma With Rhabdomyomatous Differentiation.

Thymic epithelial neoplasms with foci of rhabdomyomatous differentiation are rare. A case is presented of a primary thymic epithelial neoplasm showing the features of an atypical spindle cell thymoma that contained foci of bland-appearing rhabdomyomatous cells. The histologic and immunohistochemical features of this tumor are discussed along with a review of the literature and the comments from the AMR members to the case.

Use of a Digital Medication Management System for Effective Assessment and Enhancement of Patient Adherence to Therapy (ReX): Feasibility Study.

BACKGROUND: Medication nonadherence is a major problem in health care, imposing poor clinical outcomes and a heavy financial burden on all stakeholders. Current methods of medication adherence assessment are severely limited: they are applied only periodically, do not relate to actual pill intake, and suffer from patient bias due to errors, misunderstanding, or intentional nonadherence. ReX is an innovative medication management system designed to address poor patient adherence and enhance patient engagement with their therapy. ReX controls and tracks pills from the point of packaging right through to the patient's mouth. ReX generates robust, real-time adherence data. The system enables patients to report outcomes, complete surveys, and receive messages and instructions. ReX includes a reusable drug dispensing unit, disposable cassette containing pills, and a cloud-based data portal. OBJECTIVE: We aimed to evaluate ReX feasibility by human factor studies including evaluation of ReX safety; ReX acceptance and usability; and ReX efficacy of providing pills according to a preprogrammed dose regimen, managing reminders and adherence data, and enhancing the adherence rate compared with the standard of care. METHODS: The ReX system was evaluated in 2 human factor, nonclinical feasibility studies. Human subjects used ReX for the administration of pill-shaped Tic Tac sweets. The initial study evaluated ReX use and pill intake administration; second was a self-controlled, 4-day home-use study. All subjects took pills at home, according to a preprogrammed dose regimen, for 4 days each via the device (ReX test) or from standard packaging (control test). The adherence rate (percent of pills taken) was measured by the study subject's report, remaining pills count, and ReX records (in the ReX test). ReX safety and usability were evaluated by a questionnaire filled out by the subject. RESULTS: The initial feasibility study evaluated usability and acceptance of the ReX novel approach to pill dispensing. All subjects successfully managed 2 pill intakes. The ReX device was rated as easy to use by 81% (48/59) of subjects. The 4-day home-use study evaluated the safety, efficacy, and usability of the ReX system. No adverse event occurred; no pill overdose or pill malformation was reported. The overall adherence rate in the ReX test was 97.6% compared with 76.3% in the control test (P<.001). Real-time, personalized reminders provided in the event of a delay in pill intake contributed to 18.0% of doses taken during the ReX test. The ReX system was found easy to use by 87% (35/40) of subjects; 90% (36/40) felt comfortable using it for their medication. CONCLUSIONS: ReX's novel "tracking to the mouth" technology was found usable and accepted by subjects. The assessment of adherence rates was reliable; adherence of subjects to the dose regimen was significantly enhanced when using ReX compared with the standard of care.

Disequilibrium of fire-prone forests sets the stage for a rapid decline in conifer dominance during the 21st century.

The impacts of climatic changes on forests may appear gradually on time scales of years to centuries due to the long generation times of trees. Consequently, current forest extent may not reflect current climatic patterns. In contrast with these lagged responses, abrupt transitions in forests under climate change may occur in environments where alternative vegetation states are influenced by disturbances, such as fire. The Klamath forest landscape (northern California and southwest Oregon, USA) is currently dominated by high biomass, biodiverse temperate coniferous forests, but climate change could disrupt the mechanisms promoting forest stability (e.g. growth, regeneration and fire tolerance). Using a landscape simulation model, we estimate that about one-third of the Klamath forest landscape (500,000 ha) could transition from conifer-dominated forest to shrub/hardwood chaparral, triggered by increased fire activity coupled with lower post-fire conifer establishment. Such shifts were widespread under the warmer climate change scenarios (RCP 8.5) but were surprisingly prevalent under the climate of 1949-2010, reflecting the joint influences of recent warming trends and the legacy of fire suppression that may have enhanced conifer dominance. Our results demonstrate that major forest ecosystem shifts should be expected when climate change disrupts key stabilizing feedbacks that maintain the dominance of long-lived, slowly regenerating trees.

The incidence of occult malignancy following uterine morcellation: A ten-year single institution experience retrospective cohort study.

INTRODUCTION: When the Food and Drug Administration (FDA) initially reported on the parlous incidence (0.28%) of occult malignancy identified following uterine power morcellation, investigations thereafter documented their particular experience with this surgical procedure. Nevertheless, the precise risk of identifying a sarcoma following uterine morcellation remains indeterminate, primarily due to varying study patient risk factors, diagnostic criteria and operative approach. METHOD: We retrospectively evaluated subjects who underwent an endoscopic hysterectomy and uterine power morcellation for the treatment of a presumptive, benign indication from January 2006 until December 2015. The primary outcome was the incidence of an occult malignancy. Secondarily, we were interested in characterizing the patients' specific clinical (age, menopausal status, body mass index (BMI)) risk factors within the context of a confirmed malignant or pre-malignant pathology. RESULTS: We identified 281 patients who underwent endoscopic surgery that incorporated uterine morcellation. During the study period, one subject was ultimately diagnosed with a uterine leiomyosarcoma; the overall incidence of occult malignancy was 0.36%. There were also 3 cases of uterine premalignant disease on final pathology (2 patients had complex hyperplasia with or without atypia and 1 subject was diagnosed with a smooth muscle tumor of uncertain malignant potential (an incidence of 1.1%)). We were unable to establish any relationship between patient age, uterine weight, menopausal status or BMI and the incidence of a malignant or pre-malignant pathology (P > 0.05). CONCLUSION: The rate of occult malignancy in the present investigation was similar to previously documented studies and that which has been reported by the FDA. Additional study of methods in which to enhance preoperative work-up and mitigate the surgical risk for tumor cell dissemination is warranted.

The safety and feasibility of minimally invasive sentinel lymph node staging using indocyanine green in the management of endometrial cancer.

OBJECTIVES: The purpose of this study was to report on the feasibility of laparoscopic sentinel lymph node (SLN) staging using indocyanine green (ICG) in the management of endometrial cancer. STUDY DESIGN: We retrospectively evaluated the charts of presumed, clinical stage I endometrial cancer patients who underwent robotic-assisted surgery that incorporated mapping with ICG and SLN dissection from January 2016 until February 2017. Patient demographics, operative characteristics (e.g., complications, lymph node counts) and pathology data were evaluated. RESULTS: There were 87 patients who were included in the study. A total of 370 lymph nodes were removed, of which 245 were SLNs; unilateral and bilateral mapping of the SLNs was achieved in 84 (96.5%) and 71 (81.6%) of subjects, respectively. There were 10 (11.5%) patients who had metastatic disease identified within 22 (5.9%) of the total (n = 370) lymph nodes extracted, 19 (7.7%) of which were sentinel lymph nodes. We did not observe any intraoperative complications. CONCLUSION: The results from our study suggest that minimally invasive SLN staging using ICG is a feasible procedure that is potentially effective at detecting metastases, which may ultimately attenuate the incidence of surgical morbidity.