Nitrogen fixation in Arctic lichens and mosses: A survey across circumpolar subzones.

Nitrogen bioavailability frequently constrains primary production in the Arctic with tundra communities vulnerable to ecological and metabolic disruption from climate variability. Diazotrophs associated with lichens and mosses are the primary source of new nitrogen (N) in the Arctic. We made 526 laboratory measurements of biological nitrogen fixation (BNF) in 272 lichens and 254 bryophytes representing 23 and 39 genera, respectively.

Spatiotemporal, environmental, and behavioral predictors of Varroa mite intensity in managed honey bee apiaries.

Honey bees contribute substantially to the world economy through pollination services and honey production. In the U.S.

Mechanism of catalyst activation in iron(porphyrin)-catalysed aerobic oxidative cleavage of 2,3-dimethylindole.

Ferric porphyrins catalyse the aerobic oxidative cleavage of 2,3-dimethylindole, mimicking dioxygenase enzymes. The data herein suggest that the indole reduces the Fe(porphyrin) to Fe(porphyrin) a proton-coupled electron transfer mechanism. Subsequently, Fe(porphyrin) binds O and generates the critical superoxo intermediate, which oxidatively cleaves a second equivalent of substrate.

An Evaluation of the Relationship between Condylar Guidance, Occlusal Plane Orientation, Cuspal Inclination, and Compensatory Curves in Permanent Dentition.

Background: Understanding the relationship between condylar guidance (CG), occlusal plane orientation, cuspal inclination, and compensatory curves in natural dentition is important in orthodontics for ensuring post-treatment stability and managing temporomandibular joint disorders. Therefore, the study's objective is to assess the relationship between the compensatory curve in natural dentition, the inclination of functional cusps and occlusal plane, and CG.

Materials And Methods: Condylar guidance, occlusal plane and cuspal inclination, and the compensating curve were measured in 56 pretreatment samples (lateral cephalograms and study models).

Sprains, Strains and Growing Pains: Managing Cognitive Bias to Facilitate Timely Diagnosis in Pediatric Sports Medicine.

Background: Diagnostic delay and error represent pervasive problems in healthcare with grave implications for treatment and prognosis. Though characteristic of human cognition, cognitive biases commonly contribute to delays in the physician decision-making process, particularly in atypical or complex presentations in youth.

Methods: We present a case series of three adolescent athletes with varied clinical presentations whose diagnostic conceptualization and treatment were delayed in part due to cognitive biases with consequences for overall health and development, as well as return to sport.

Left-right cortical interactions drive intracellular pattern formation in the ciliate Tetrahymena.

In ciliates, cortical organelles, including ciliary arrays, are positioned at precise locations along two polarity axes: anterior-posterior and circumferential (lateral). We explored the poorly understood mechanism of circumferential patterning, which generates left-right asymmetry. The model ciliate Tetrahymena has a single anteriorly-located oral apparatus.

SoLoArc: A device for free field multiplanar sound localization testing.

This paper describes a multiyear interdisciplinary collaborative project to design, build, and test a device to dynamically explore free field sound localization in azimuth and elevation: the SoLoArc (Sound Localization Arc). The project served as a pedagogical tool to engage undergraduate students in the designing, building, and testing of a scientific instrument from start to finish. Further, the device was used as a teaching tool, allowing the comparison of the results of sound localization experiments in the free field using the SoLoArc to results from artificial sound localization cues across several semesters of an undergraduate course on sensation and perception.

The Role of Membrane-Bound Extracellular Vesicles During Co-Stimulation and Conjugation in the Ciliate .

During sexual reproduction, the freshwater ciliate sheds membrane-bound vesicles into the extracellular environment (cEMVs: ciliary extracellular micro-vesicles). We provide evidence that 100 nm vesicles shed from the cilia of starved cells promote mating between cells of complementary mating types. A proteomic analysis revealed that these EMVs are decorated with mating-type proteins expressed from the MAT locus, proteins that define a cell's sex (one of seven).

Measuring Health-Related Social Risks in a Lung Cancer Screening Cohort.

Objective: To evaluate the feasibility and limitations of measuring health-related social risks (HRSRs) affecting individuals in a lung cancer screening (LCS) cohort from multiple data sources.

Methods: A single-institution study analyzed data from 227 participants in a pragmatic LCS trial in west and southwest Philadelphia. HRSRs were assessed using three approaches: (1) electronic health records (EHRs) capturing individual-level social risks (eg, financial strain, housing stability); (2) neighborhood-level analysis using a modified Yost index to determine socio-economic status; and (3) semistructured interviews with 15 participants to identify barriers and facilitators to LCS adherence.

Chasing the Niche: Escaping Climate Change Threats in Place, Time, and Space.

Climate change is creating mismatches between species' current environments and their historical niches. Locations that once had the abiotic and biotic conditions to support the persistence of a species may now be too warm, too dry, or simply too different, to meet their niche requirements. Changes in behaviors, altered phenology, and range shifts are common responses to climate change.

Personal growth through navigating the world as an artist: a qualitative study of the impact of creativity camp on adolescents with depression.

Background: A growing body of literature suggests that creative arts interventions can effectively support mental health and well-being in young people. We recently reported that after participating in "Creativity Camp"- a 2-week creative arts group intervention- 69 adolescents with depression showed significantly reduced depression symptoms and improved ratings of well-being. To understand the key processes impacting adolescents during and after this intervention, this study applies a multi-informant qualitative data approach.

Importin-9 and a TPR domain protein MpH drive periodic patterning of ciliary arrays in Tetrahymena.

We explored how the number of structures is determined in an intracellular organelle series. In Tetrahymena, the oral apparatus contains three diagonal ciliary rows: M1, M2, and M3. During development, the M rows emerge by sequential segmentation of a group of basal bodies, starting with the longest and most anterior M1 and ending with the shortest and most posterior M3.

Selective benefit of the sucrose TonB-dependent receptor, SucA, in .

Gram-negative bacteria have outer membrane proteins called TonB-dependent receptors (TBDRs) that facilitate energy-dependent transport of substrates. is a gram-negative bacterium with a large set of TBDRs, yet the function of many of these TBDRs remains uncharacterized. This study focuses on SucA, a TBDR that transports sucrose.

Impact of Vitamin D3 on Postorthodontic Treatment Stability: A Randomized Controlled Trial.

Aim: This study aims to clinically evaluate whether the local administration of vitamin D3 enhances postorthodontic tooth stability over a period of 3 months immediately after debonding.

Materials And Methods: Patients aged 15-30 years with dental malocclusion and moderate crowding in the lower arch (Little's irregularity score of 4-6) were selected and randomly split into the experimental and the control groups. After complete alignment and leveling, vitamin D3 injection was delivered to the experimental group and the control group was given a placebo injection with 0.

Regulation of , a sucrose-inducible promoter in .

In gram-negative bacteria, when nutrients are too large or too scarce to diffuse through outer membrane porins, TonB-dependent receptors (TBDRs) are utilized to actively translocate substrates across the outer membrane. is a gram-negative bacterium with a large set of TBDRs, many which have not been fully characterized. Previous studies identified SucA, a TBDR that transports sucrose.

Bedmap3 updated ice bed, surface and thickness gridded datasets for Antarctica.

We present Bedmap3, the latest suite of gridded products describing surface elevation, ice-thickness and the seafloor and subglacial bed elevation of the Antarctic south of 60 °S. Bedmap3 incorporates and adds to all post-1950s datasets previously used for Bedmap2, including 84 new aero-geophysical surveys by 15 data providers, an additional 52 million data points and 1.9 million line-kilometres of measurement.

Neural and behavioral evolution in an eavesdropper with a rapidly evolving host.

The diversification of animal communication systems is driven by the interacting effects of signalers, signal receivers, and the environment. Yet, the critical role of unintended receivers, like eavesdropping enemies, has been underappreciated. Furthermore, contemporary evolution of animal signals is rare, making it difficult to directly observe this process.

Modeling critical dosing strategies for stromal-induced resistance to cancer therapy.

Complex interactions between stromal cells, tumor cells and therapies can influence environmental factors that in turn impact anticancer treatment efficacy. Disentangling these phenomena is critical for understanding treatment response and designing effective dosing strategies. We propose a mathematical model for a common tumor-stromal interaction motif where stromal cells secrete factors that promote drug resistance.

The Impact of Injectable Platelet-rich Fibrin on Orthodontic Tooth Movement during Retraction: A Randomized Controlled Trial.

Aim: This study intended to comprehend the effects of injectable platelet-rich fibrin (i-PRF) on anchor loss and space closure rates during the retraction phase of orthodontic treatment.

Materials And Methods: Twenty-four participants with malocclusion, necessitating extractions and space closure during orthodontic treatment, were enrolled and divided into two groups ( = 12 participants) group A: the experimental group was administered i-PRF on the maxilla/mandible, while group B: the control group did not. Measurements of the rate of space closure, anchor loss, and salivary enzyme activity were done before retraction (T0), after three weeks (T1), after six weeks (T2), and after nine weeks (T3).

The 'Janus A' gene encodes a polo-kinase whose loss creates a dorsal/ventral intracellular homeosis in the ciliate, .

Genetic studies on the protist, provide a glimpse into the unexpectedly rich world of intracellular patterning that unfolds within the ciliate cell cortex. Ciliate pattern studies provide a useful counterpoint to animal models of pattern formation in that the unicellular model draws attention away from fields of cells (or nuclei) as the principal players in the metazoan pattern paradigm, focusing instead on fields of ciliated basal bodies serving as sources of positional information. In this study, we identify , a Polo kinase of , that serves as an important factor driving global, circumferential pattern.

A cluster randomized trial of xylitol chewing gum for prevention of preterm birth: The PPaX trial.

Background: Maternal periodontal disease is associated with preterm and low-birthweight deliveries, but randomized trials of likely efficacious treatments (e.g., dental scaling and root planing) during pregnancy have not reduced these adverse outcomes.

Photoactivatable O-GlcNAc Transferase Library Enables Covalent Chemical Capture of Solvent-Exposed TPR Domain Interactions.

O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) is an essential, stress-sensing enzyme responsible for adding the O-GlcNAc monosaccharide to thousands of nuclear and cytoplasmic proteins to regulate cellular homeostasis. OGT substrates are found in almost all intracellular processes, and perturbations in protein O-GlcNAc levels have been implicated in proteostatic diseases, such as cancers, metabolic disorders, and neurodegeneration. This broad disease activity makes OGT an attractive therapeutic target; however, the substrate diversity makes pan-inhibition as a therapeutic strategy unfeasible.