Impact of prescribed fire on soil microbial communities in a Southern Appalachian Forest clear-cut.

Escalating wildfire frequency and severity, exacerbated by shifting climate patterns, pose significant ecological and economic challenges. Prescribed burns, a common forest management tool, aim to mitigate wildfire risks and protect biodiversity. Nevertheless, understanding the impact of prescribed burns on soil and microbial communities in temperate mixed forests, considering temporal dynamics and slash fuel types, remains crucial. Our study, conducted at the University of Tennessee Forest Resources AgResearch and Education Center in Oak Ridge, TN, employed controlled burns across various treatments, and the findings indicate that low-intensity prescribed burns have none or minimal short-term effects on soil parameters but may alter soil nutrient concentrations, as evidenced by significant changes in porewater acetate, formate, and nitrate concentrations. These burns also induce shifts in microbial community structure and diversity, with Proteobacteria and Acidobacteria increasing significantly post-fire, possibly aiding soil recovery. In contrast, Verrucomicrobia showed a notable decrease over time, and other specific microbial taxa correlated with soil pH, porewater nitrate, ammonium, and phosphate concentrations. Our research contributes to understanding the intricate relationships between prescribed fire, soil dynamics, and microbial responses in temperate mixed forests in the Southern Appalachian Region, which is valuable for informed land management practices in the face of evolving environmental challenges.

Design and testing of a high perveance sheet beam electron gun.

This paper presents the design, prototype engineering, and initial testing of a relatively low-voltage, high aspect ratio electron gun for versatile pulsed power applications. The sheet beam, diode electron gun is designed for (23-25) kV voltage and 6 µA/V1.5, as is required for x-band klystron, as a part of a compact Klylac delivering electron beam energy in the MeV range. The gun prototype was engineered, built, and tested using a Scandinova M1-0.5 modulator. Beam loss on the anode aperture is evaluated from transient waveforms and equivalent circuit modeling.

An Unusual Presentation of Intussusception.

This is the case of a 9-month-old female infant who presented to the emergency department with a history of several episodes of nonbilious and nonbloody emesis. The patient was found to be afebrile with normal vital signs and an otherwise normal physical examination. Initial plain film radiography was concern for possible obstruction. Imaging studies with ultrasonogram demonstrated intussusception. This was an unusual case of intussusception because children are typically more ill-appearing with vomiting, diarrhea, fevers, lethargy, and blood in stool. Management options included surgery, pneumatic enema reduction, and barium enema reduction. Pneumatic enema reduction was performed. This procedure has been shown to have superior outcomes in infants with intussusception. Advanced practice providers need to provide a detailed history, complete a thorough physical examination, order the appropriate diagnostics, and be vigilant of the clinical manifestation of intussusception.

Management of Hand Injuries: Part III.

Assessment of Acute Hand Injuries was discussed in Part I (). Part I reviewed approaches to the assessment of the patient with a hand injury and established a process for basic identification of the hand structures and function. Approaches to history taking and specific evaluations for the hand were discussed, and examples of the assessments were provided. Diagnostic approaches to support physical findings were discussed, and methods of radiological assessment provided assistance to the audience in making appropriate diagnosis in relation to hand injuries. Management of bony hand injuries was discussed in Part II. In Part II, the authors also described the epidemiology, radiographs, and the management of hand lacerations, fingertip injuries, and fractures. In this article, Part III, the management of tendon, ligamentous, neurovascular, and other specific hand injuries, along with the management of selected chronic hand conditions, is discussed.

Novel method for the formation of monodisperse superheated perfluorocarbon nanodroplets as activatable ultrasound contrast agents.

Microbubble (MB) contrast agents have positively impacted the clinical ultrasound (US) community worldwide. Their use in molecular US imaging applications has been hindered by their limited distribution to the vascular space. Acoustic droplet vaporization (ADV) of nanoscale superheated perfluorocarbon nanodroplets (NDs) demonstrates potential as an extravascular contrast agent that could facilitate US-based molecular theranostic applications. However these agents are metastable and difficult to manufacture with high yields. Here, we report a new formulation technique that yields reliable, narrowly dispersed sub-300 nm decafluorobutane (DFB) or octafluoropropane (OFP)-filled phospholipid-coated NDs that are stable at body temperature, using small volume microfluidization. Final droplet concentration was high for DFB and lower for OFP (>1012vs. >1010 NDs per mL). Superheated ND stability was quantified using tunable resistive pulse sensing (TRPS) and dynamic light scattering (DLS). DFB NDs were stable for at least 2 hours at body temperature (37 °C) without spontaneous vaporization. These NDs are activatable in vitro when exposed to diagnostic US pressures delivered by a clinical system to become visible microbubbles. The DFB NDs were suficiently stable to allow their processing into functionalized NDs with anti-epithelial cell adhesion molecule (EpCAM) antibodies to target EpCAM positive cells.

Management of Hand Injuries: Part II.

Hand injuries are a frequent emergency department occurrence and account for most upper extremity injuries. Proper assessment and management of hand injuries can reduce morbidity and prevent long-term disability. "Assessment of Acute Hand Injuries" Part I was discussed in the Advanced Emergency Nursing Journal (). Part II herein discusses the epidemiology, radiographs, and the management of hand lacerations, fingertip injuries, and fractures. Part III will discuss the management of tendon, ligamentous, neurovascular, and other special hand injuries along with the management of selected chronic hand conditions.

Mitogen and stress-activated kinases 1/2 regulate ischemia-induced hippocampal progenitor cell proliferation and neurogenesis.

Pathophysiological conditions such as cerebral ischemia trigger the production of new neurons from the neurogenic niche within the subgranular zone (SGZ) of the dentate gyrus. The functional significance of ischemia-induced neurogenesis is believed to be the regeneration of lost cells, thus contributing to post-ischemia recovery. However, the cell signaling mechanisms by which this process is regulated are still under investigation. Here, we investigated the role of mitogen and stress-activated protein kinases (MSK1/2) in the regulation of progenitor cell proliferation and neurogenesis after cerebral ischemia. Using the endothelin-1 model of ischemia, wild-type (WT) and MSK1(-/-)/MSK2(-/-) (MSK dKO) mice were injected with BrdU and sacrificed 2 days, 4 weeks, or 6 weeks later for the analysis of progenitor cell proliferation, neurogenesis, and neuronal morphology, respectively. We report a decrease in SGZ progenitor cell proliferation in MSK dKO mice compared to WT mice. Moreover, MSK dKO mice exhibited reduced neurogenesis and a delayed maturation of ischemia-induced newborn neurons. Further, structural analysis of neuronal arborization revealed reduced branching complexity in MSK dKO compared to WT mice. Taken together, this dataset suggests that MSK1/2 plays a significant role in the regulation of ischemia-induced progenitor cell proliferation and neurogenesis. Ultimately, revealing the cell signaling mechanisms that promote neuronal recovery will lead to novel pharmacological approaches for the treatment of neurodegenerative diseases such as cerebral ischemia.