Plexiform fibrohistiocytic tumor (PFHT) is a rare locally aggressive and rarely metastasizing mesenchymal neoplasm that most commonly arises in the upper extremities of children and young adults. It typically presents as a small, slow-growing, painless, dermal or subcutaneous mass. Magnetic resonance imaging (MRI) often reveals a plaque-like or infiltrative lesion with intermediate signal intensity on T1-weighted sequences and high signal intensity on T2-weighted sequences. Contrast-enhanced MRI demonstrates moderate or avid enhancement. Histologically, PFHT is characterized by a multinodular or plexiform proliferation of a variable admixture of histiocyte-like cells, osteoclast-like giant cells and elongated spindle cells. Immunohistochemically, the histiocyte-like and osteoclast-like giant cells express CD68, CD163 and CD11c, whereas the spindle cells are focally positive for smooth muscle actin. Most notably, cyclin D1 immunostaining demonstrates nuclear expression in the histiocyte-like and osteoclast-like giant cells as well as spindle cells. Wide local excision with long-term follow-up is generally considered optimal management for conventional cases. This review provides an updated overview of the clinical, radiological, histological, immunohistochemical, cytogenetic and molecular genetic features of PFHT and discusses the differential diagnosis of this enigmatic neoplasm.

IntroductionSeeking emergency care regarding musculoskeletal sensations is far more prevalent than limb or life-threatening pathophysiology. We studied the ability of an LLM to distinguish between urgent and nonurgent upper extremity symptoms and provide an accurate diagnosis.MethodsFive LLMs (ChatGPT-4, ChatGPT-4o, Co-Pilot, Gemini, and PerplexityChat) were presented with descriptions of seven urgent and seven nonurgent symptom scenarios written below a sixth grade reading level. LLM responses were identified as appropriate if immediate urgent medical attention was recommended after an initial and ongoing inquiry ("What additional information do you need to diagnose my condition?"). Diagnoses provided were identified as correct, partially correct, or incorrect. The analysis was repeated 24 months later with the current LLM versions and results were compared.ResultsLLMs discerned nonurgent conditions with 97% positive predictive value (PPV) and an 89% negative predictive value (NPV) on initial query, which improved to 96% and 97% respectively after ongoing inquiry. Compartment syndrome was misidentified as nonurgent in 80% of scenarios on initial inquiry, although four of five LLMs corrected on continued inquiry. Diagnosis was correct or partially correct for 115 of 150 (82%) on initial inquiry. An updated analysis 24 months later demonstrated marked improvement in LLM ability to identify emergencies with 100% PPV and 95% NPV on initial query and 98% NPV after ongoing inquiry.ConclusionThe finding that LLMs can distinguish urgent from nonurgent upper extremity conditions suggests that artificial intelligence tools could help reduce unnecessary use of high-cost emergency services, allowing those resources to be reserved for patients who require timely care.

Decentralized, farmer-scale biochar production can valorize agricultural residues for soil amendment and carbon storage while avoiding the feedstock-transport burden of centralized pyrolysis. This study compared three low-capital, field-deployable kiln architectures for an on-farm self-supply user: an open flame-curtain Traditional Oregon Kiln (TOK, Type A), a Controlled-Draft Flame-Curtain Kiln (CDFC, Type B), and an Indirect-Heat Fine-Feedstock Retort (IHFRt, Type C). A unified techno-economic model was parameterized with experimental yields and charring times for corn cob, corn stalk, and sorghum stover (n=15 batches per kiln). At a 50kg batch, 100dyr-1 of operation, a wage of 16.50USDh-1, and a 7% discount rate over a 10-yr life, the estimated minimum selling prices (MSP, oven-dry basis) were 3.06USDkg-1 (Type A), 2.60USDkg-1 (Type B), and 1.74USDkg-1 (Type C). Capital cost was small (876-1416 USD, <3% of levelized cost), whereas labor contributed more than 95% and dominated sensitivity. Type C achieved the lowest MSP because its passive charring phase decoupled operator hours from conversion time, raising biochar output per labor hour by 80%. Against the 3USDkg-1 to 5USDkg-1 U.S. retail price for comparable specialty biochar, Type C undercut even the low end and Type A remained competitive at the upper end. A 10,000-draw Monte Carlo preserved the Type C < Type B < Type A ranking in 99.9% of draws. A paired life-cycle assessment of kiln emissions and the soil-organic-carbon foregone by residue removal is the necessary next step before net climate benefits can be claimed.

With the emergence of artificial intelligence (AI) in recent decades, AI literacy has become a critical component of K-12 education. Although research on AI literacy in K-12 education continues to advance, existing studies have largely focused on its definition and conceptualization. There is limited empirical research on the influencing factors of AI literacy, and even less at the primary education level. To address this gap, the present study aimed to explore the relationships among key influencing factors (i.e., affective, behavioral, self-perceived cognitive, and ethical) and their associations with AI literacy acquisition. This study collected a sample of 445 primary school students (aged 8-12), and then structural equation modeling was conducted. To control for potential confounding effects and improve the robustness of the results, background variables were added to the research model. The results of this study revealed a set of positive associations, wherein affective factors are linked to behavioral factors, which in turn are linked to self-perceived cognitive and ethical factors, and to AI literacy acquisition. The result also revealed a suppression effect of the ethical factor on the link between students' self-perceptions and their actual test performance, which suggests a new research direction in AI literacy education. The study enriches our conceptual understanding of AI literacy by revealing the relational structure among its cognitive and non-cognitive components in the primary school context, extending the emergent research line to both dimensions. The findings could provide actionable insights for researchers and educators seeking to explore and integrate AI literacy instruction in primary education.

A central paradigm in plant biology is that there is a trade-off between growth and defence. We propose that Epichloë fungal endophytes relieve this trade-off in plants by the fungal-derived production of antiherbivore alkaloids. Lolium perenne plants without (nil) and with Epichloë LpTG-3 sp. strain AR37 able (wild type (wt), ΔidtA) and unable (ΔidtM) to produce bioactive indole diterpene alkaloids were subjected to an exogenous application of gibberellin (GA) hormone followed by a challenge with Rhopalosiphum padi aphids. The GA-derived plant growth promotion increased the susceptibility to aphids in both nil plants and ΔidtM-associated plants but did not affect the aphid resistance in either wt- or ΔidtA-associated plants. GA treatment changed the composition of AR37-derived alkaloids, reduced the concentration of AR37-derived epoxyjanthitrem alkaloids in wt-associated plants and reduced the amount of mycelial biomass of AR37 variants. GA treatment generally increased expression of plant genes related to abscisic acid (ABA), auxin, cell division, cell wall and GA (e.g., YUCCA2, GA2ox3), reduced expression of photosynthesis-related genes (e.g., RBCS1), and had mixed effects on the expression of plant immunity-related genes (e.g., PR-1). GA treatment increased concentrations of ABA, salicylic acid, and jasmonic acid, and did not affect auxin concentrations. Additionally, soil derived from GA-treated plants showed increased abundance of putative bacterial taxa that included plant growth-promoting members (e.g., Bryobacter). Our findings demonstrate that the AR37-derived production of indole diterpene alkaloids was the key mechanism that relieved the growth-defence trade-off of plants.