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Summary: Evergreen conifer forests are the most prevalent land cover type in North America. Seasonal changes in the color of evergreen forest canopies have been documented with near‐surface remote sensing, but the physiological mechanisms underlying these changes, and the implications for photosynthetic uptake, have not been fully elucidated.Here, we integrate on‐the‐ground phenological observations, leaf‐level physiological measurements, near surface hyperspectral remote sensing and digital camera imagery, tower‐based CO2 flux measurements, and a predictive model to simulate seasonal canopy color dynamics.We show that seasonal changes in canopy color occur independently of new leaf production, but track changes in chlorophyll fluorescence, the photochemical reflectance index, and leaf pigmentation. We demonstrate that at winter‐dormant sites, seasonal changes in canopy color can be used to predict the onset of canopy‐level photosynthesis in spring, and its cessation in autumn. Finally, we parameterize a simple temperature‐based model to predict the seasonal cycle of canopy greenness, and we show that the model successfully simulates interannual variation in the timing of changes in canopy color.These results provide mechanistic insight into the factors driving seasonal changes in evergreen canopy color and provide opportunities to monitor and model seasonal variation in photosynthetic activity using color‐based vegetation indices. [ABSTRACT FROM AUTHOR]

At the seasonal time scale, daily photochemical reflectance index (PRI) measurements track changes in photoprotective pigment pools as plants respond to seasonally variable environmental conditions. As such, remotely sensed PRI products present opportunities to study seasonal processes in evergreen conifer forests, where complex vegetation dynamics are difficult to capture due to small annual changes in chlorophyll content or leaf structure. Because PRI is tied explicitly to short‐ and long‐term changes in photoprotective pigments that are responsible for regulating stress, we hypothesize that PRI by extension could serve as a proxy for stomatal response to seasonally changing hydroclimate, assuming plant functional responses to stress covary in space and time. To test this, we characterized PRI in a semiarid, montane mixed conifer forest in the Madrean sky islands of Arizona, USA, during the monsoon growing season subject to precipitation pulse dynamics. To determine the sensitivity of PRI to ecohydrologic variability and associated changes in gross primary productivity (GPP), canopy spectral measurements were coupled with eddy covariance CO2 flux and sap flow measurements. Seasonally, there was a significant relationship between PRI and sap flow velocity (R2 = 0.56), and multiple linear regression analysis demonstrated a PRI response to dynamic water and energy limitations in this system. We conclude that PRI has potential to serve as a proxy for forest functional response to seasonal ecohydrologic forcing. The coordination between photoprotective pigments and seasonal stomatal regulation demonstrated here could aid characterization of vegetation response to future changes in hydroclimate at increasing spatial scales. Plain Language Summary: In order to understand how ecosystems interact with climate and how these relationships may change under future conditions, it is necessary to study how carbon and water move between plants and the atmosphere and how environmental stress, such as changing water availability, impacts these processes. For decades, satellites used in remote sensing studies have been able to measure how "green" an ecosystem is, but for forests that remain visibly green year‐round even under stressful conditions, these greenness indices may not probe deeply enough beneath the surface to provide a clear picture of plant function. An alternative reflectance‐based index, termed the photochemical reflectance index, or PRI, is able to detect seasonal changes in leaf pigments that are responsible for regulating plant stress. Here, we use tower‐based PRI data from a semiarid conifer forest to show that variations in PRI correspond to the way in which plants regulate their water loss as moisture and temperature conditions change throughout the growing season. This result demonstrates that PRI is an effective indicator of how ecosystems respond to stressful environmental conditions, and therefore has the potential to advance our ability to distinguish how water availability influences forest productivity. Key Points: We report a novel relationship between seasonal photochemical reflectance index and sap flow in a mature conifer forestThe photochemical reflectance index responded to seasonal water and energy limitations due to its association with photoprotectionThe photochemical reflectance index has remarkable potential as a proxy for forest functional response to seasonal ecohydrologic forcing [ABSTRACT FROM AUTHOR]

Background Limited outcome data exist regarding partial-oral antibiotic therapy, defined as oral antibiotics as part of a patient's treatment, for bone and joint infections (BJIs) in people who inject drugs (PWID). Methods We conducted a retrospective study of all PWID reporting drug use within 3 months and BJIs requiring ≥6 weeks of antibiotics in an urban safety-net hospital between February 1, 2019, and February 1, 2021. Treatment outcomes were assessed by chart review. Rates of failure, defined as death, symptoms, or signs concerning for worsening or recurrent infections, were assessed 90 and 180 days after completion of antibiotics. Univariate logistic regression was used to explore the association between covariates and failure. Results Of 705 patients with BJI, 88 (13%) were PWID. Eighty-six patients were included in the final cohort. Forty-four (51%) were homeless, 50 (58%) had spine infection, 68 (79%) had surgery, and 32 of 68 (47%) had postoperatively retained hardware. Twelve (14%) of 86 patients received exclusively intravenous (IV) antibiotics, and 74 (86%) received partial-oral antibiotics. Twelve (14%) of 86 patients had patient-directed discharge. In those who received partial-oral antibiotics, the failure rate was 20% at 90 days and 21% at 180 days after completion of intended treatment. Discharge to a medical respite and follow-up with infectious diseases (ID) or surgery were negatively associated with odds of failure. Conclusions Partial-oral treatment of BJI in PWID was a common practice and often successful when paired with medical respite and follow-up with ID or surgery. [ABSTRACT FROM AUTHOR]

A novel concept is proposed and verified, experimentally and theoretically, to manipulate droplets without external power sources. The proposed device is a hydrophobic surface containing specific roughness gradients, which is composed of several textured regions with gradually increased structural roughness. Hydrophobic materials of four types, photoresist AZ6112, Teflon, Parylene C, and plasma polymerization fluorocarbon film (PPFC)—are adopted to fabricate the textured surfaces, and are tested. Actuating forces come from the different Laplace pressures exerted on a droplet across various hydrophobic surfaces, whereas resistance forces come from the contact-angle hysteresis. Two patterns of devices are shown in this article-chain-shaped and concentric circular. The former functions as a droplet transport route and the latter provides both transport and orientation functions. Theoretical estimation and experimental verification of the droplet motion, including actuation and resistance forces, on the device are conducted. Optimal design is achieved based on accurate estimations of the acting forces. The proposed device provides a simplified fabrication process and shows superior biocompatibility for droplet manipulation in microfluidic systems. [ABSTRACT FROM AUTHOR]

Pneumococcal conjugate vaccine (PCV) introduction has reduced pneumococcal meningitis incidence. The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project described the serotype distribution of remaining pneumococcal meningitis in countries using PCV10/13 for least 5–7 years with primary series uptake above 70%. The distribution was estimated using a multinomial Dirichlet regression model, stratified by PCV product and age. In PCV10-using sites (N = 8; cases = 1141), PCV10 types caused 5% of cases <5 years of age and 15% among ≥5 years; the top serotypes were 19A, 6C, and 3, together causing 42% of cases <5 years and 37% ≥5 years. In PCV13-using sites (N = 32; cases = 4503), PCV13 types caused 14% in <5 and 26% in ≥5 years; 4% and 13%, respectively, were serotype 3. Among the top serotypes are five (15BC, 8, 12F, 10A, and 22F) included in higher-valency PCVs under evaluation. Other top serotypes (24F, 23B, and 23A) are not in any known investigational product. In countries with mature vaccination programs, the proportion of pneumococcal meningitis caused by vaccine-in-use serotypes is lower (≤26% across all ages) than pre-PCV (≥70% in children). Higher-valency PCVs under evaluation target over half of remaining pneumococcal meningitis cases, but questions remain regarding generalizability to the African meningitis belt where additional data are needed. [ABSTRACT FROM AUTHOR]