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In recent years, hand drying has been highlighted as a key step in appropriate hand hygiene, as moisture on hands can increase the transfer of micro-organisms from hands to surfaces and vice versa. To understand bacterial and viral aerosolization following hand drying, and study the transfer of micro-organisms from hands to surfaces after drying using different methods. Groups of five volunteers had their hands pre-washed with soap, rinsed and dried, then inoculated with a concentrated mixture of Pseudomonas fluorescens and MS2 bacteriophage. Volunteers entered an empty washroom, one at a time, and rinsed their hands with water or washed their hands with soap prior to drying with a jet dryer or paper towels. Each volunteer applied one hand successively to various surfaces, while their other hand was sampled using the glove juice method. Both residual bacteria and viruses were quantified from the washroom air, surface swabs and hand samples. P. fluorescens and MS2 bacteriophages were rarely aerosolized while drying hands for any of the drying methods studied. Results also showed limited, and similar, transfer of both micro-organisms studied on to surfaces for all drying methods. The use of jet dryers or paper towels produces low levels of aerosolization when drying hands in a washroom. Similarly, all drying methods result in low transfer to surfaces. While the coronavirus disease 2019 pandemic raised concerns regarding public washrooms, this study shows that all methods tested are hygienic solutions for dry washed hands. [ABSTRACT FROM AUTHOR]

Osteoporosis is one of the most common skeletal diseases, but current therapies are limited to generalized antiresorptive or anabolic interventions, which do not target regions that would benefit from improvements to skeletal health. To improve the evaluation of treatment plans, we used a spatio-temporal multiscale approach that combines longitudinal in vivo micro-computed tomography (micro-CT) and in silico subject-specific finite element modeling to quantitatively map bone adaptation changes due to disease and treatment at high resolution. Our findings show time and region-dependent modifications in bone remodelling following one and two sets of mechanical loading and/or pharmacological interventions. The multiscale results highlighted that the distal section was unaffected by mechanical loading alone but the proximal tibia had the greatest gain from positive interactions of combined therapies. Mechanical loading abated the catabolic effect of PTH, but the main benefit of combined treatments occurred from the additive interactions of the two therapies in periosteal apposition. These results provide detailed insight into the efficacy of combined treatments, facilitating the optimisation of dosage and treatment duration in preclinical mouse studies, and the development of novel interventions for skeletal diseases. Combined mechanical loading and pharmacotherapy have the potential to slow osteoporosis-induced bone loss but current therapies do not target the regions in need of strengthening. We show for the first time spatial region-dependant interactions between PTH and mechanical loading treatment in OVX mouse tibiae, highlighting local regions in the tibia that benefitted from separate and combined treatments. Combined experimental-computational analysis also detailed the lasting period of each treatment per location in the tibia, the extent of positive (or negative) interactions of the combined therapies, and the impact of each treatment on the regulation of bone adaptation spatio-temporally. This approach can be used to create hypothesis about the interactions of different treatments to optimise the design of biomaterials and medical interventions. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Aneurysmal subarachnoid hemorrhage (aSAH) and traumatic subarachnoid hemorrhage (tSAH) differ significantly in their mortality and management. Although computed tomography angiography (CTA) is critical to guide timely interventions in aSAH, it lacks recognized benefit in assessing tSAH. Despite this, CTA commonly is included in tSAH evaluation.Objective: Determine if any clinically significant cerebral aneurysms are identified on CTA in emergency department (ED) patients with a tSAH.Methods: Retrospective observational study of consecutive blunt head trauma patients ages ≥ 16 years with Glasgow Coma Scale score (GCS) ≥ 13 who presented to an academic ED (100,000 annual visits) over a 7-year period. Those included had a CT-diagnosed SAH and underwent head CTA. The primary endpoint was the detection of any clinically significant brain aneurysms.Results: There were 297 patients that met the inclusion criteria. Twenty-six patients (8.8%) had an incidental aneurysm discovered; one underwent elective outpatient intervention. Aneurysm-positive patients were more likely to be female (69.2% vs. 46.9%, p = 0.003), age 60 years or older (80.8% vs. 52.4%, p = 0.005), and be on anticoagulation (42.3% vs. 28.0%, p = 0.03). There were no differences between the aneurysm-positive and -negative patients with respect to GCS, history of hypertension, or mechanism of injury.Conclusions: In this 7-year retrospective chart review, CTA in patients with tSAH and GCS ≥ 13 did not reveal any clinically relevant cerebral aneurysms. One incidental aneurysm later underwent outpatient neurovascular intervention. In the absence of specific clinical concerns, CTA has minimal value in well-appearing patients with a tSAH. [ABSTRACT FROM AUTHOR]

Osteoporosis disrupts the healthy remodelling process in bone and affects its mechanical properties. Mechanical loading has been shown to be effective in stimulating bone formation to mitigate initial bone loss. However, no study has investigated the effects of repeated mechanical loading, with a pause of one week in between, in the mouse tibia with oestrogen deficiency. This study uses a combined experimental and computational approach, through longitudinal monitoring with micro-computed tomography, to evaluate the effects of loading on bone adaptation in the tibiae of ovariectomised (OVX) C57BL/6 mice from 14 to 22 weeks of age. Micro-FE models coupled with bone adaptation algorithms were used to estimate changes in local tissue strains due to OVX and mechanical loading, and to quantify the relationship between local strain and remodelling. The first in vivo mechanical loading increased apposition, by 50–150%, while resorption decreased by 50–60%. Both endosteal and periosteal resorption increased despite the second mechanical loading, and periosteal resorption was up to 70% higher than that after the first loading. This was found to correlate with an initial decrease in average strain energy density after the first loading, which was lower and more localised after the second loading. Predictions of bone adaptation showed that between 50 and 90% of the load-induced bone apposition is linearly strain driven at the organ-level, but resorption is more biologically driven at the local level. The results imply that a systematic increase in peak load or loading rate may be required to achieve a similar bone adaptation rate in specific regions of interests. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Oestrogen deficiency-related bone loss in the ovariectomized (OVX) mouse is a common model for osteoporosis. However, a comprehensive in vivo assessment of intervention-related changes in multiple bone properties, and in multiple mouse strains, is required in order to identify an appropriate model for future evaluation of novel anti-osteoporotic therapies. The aim of this study was to evaluate the effect of OVX on the morphometric and densitometric properties measured in the microCT images and the mechanical properties estimated with finite element models of the tibia in two mouse strains, C57BL/6 and BALB/c. 14-weeks-old female C57BL/6 and BALB/c mice were divided into two groups per strain: (1) ovariectomized, (2) non-operated control. The right tibia was scanned at baseline (14 weeks) and then every two weeks thereafter, until 24-weeks-old, using in vivo microCT. Changes in trabecular and cortical bone morphometry, spatiotemporal changes in densitometric properties and in mechanical properties (from micro-finite element (μFE) analysis) were computed. Differences between OVX and non-operated controls were evaluated by ANCOVA, adjusted for 14-weeks baseline. In morphometry, trabecular bone mass was significantly reduced in both C57BL/6 and BALB/c from four weeks following surgery. Though the OVX-effect was transient in BALB/c as bone mass reached skeletal homeostasis. OVX inhibited the age-related thickening of cortical bone only in C57BL/6. In both strains, increments in bone mineral content were significantly lower with OVX only in the proximal tibia, with intervention-related differences increasing with time. OVX had no effect on μFE estimates of stiffness nor failure load in either strain. The results of this study show strain-, time- and region-(trabecular or cortical) dependent changes in morphometric and densitometric properties. These findings highlight the importance of choosing an appropriate mouse model and time points for research of treatments against accelerated bone resorption. • Trabecular bone loss is persistent in C57BL/6 and transient in BALB/c to 10 weeks following ovariectomy • Oestrogen-deficiency inhibits cortical thickening, due to endosteal resorption, in C57BL/6 but not in BALB/c mice • Ovariectomy-effects on bone mineral content are predominantly localised to the proximal tibia in both C57BL/6 and BALB/c • Ovariectomy did not affect μFE estimates of bone mechanics despite changes in bone morphometric and densitometric properties • Bone structural changes that lead to bone fragility with oestrogen-deficiency should be monitored in preclinical studies [ABSTRACT FROM AUTHOR]

Highlights • Glass electrode soil pH sensors correlated to the laboratory standard. • Domain reflectometry soil moisture sensors correlated to the laboratory standard. • Conductivity soil moisture sensors quality was correlated to sensor price. Abstract Soil moisture and pH levels directly affect urban tree performance. An accurate sensor to assess these soil conditions would allow arborists and urban foresters to make and evaluate management actions. These actions may then be used to improve tree species diversity and site quality. Toward this goal, twenty-one soil pH and moisture sensors were tested for their ability to accurately and precisely measure soil pH, volumetric soil moisture content (VMC), or both. This research was conducted on four different soil texture classes (loamy sand, sandy loam, clay loam, and clay) at three different moisture levels (air dry, ≈ 0.5 field capacity, and ≈ field capacity). Soil pH sensors using a glass-electrode in a 1:2 (soil:deionized water) solution were found to accurately and precisely measure soil pH (P = <0.0001; ρ c = >0.95). However, sensors using metal electrodes inserted into the soil had no significant correlation to soil pH levels (P = >0.1; ρ c = <0.2). When selecting a soil pH sensor, measurement method may be the most important consideration. Soil VMC sensors using time domain reflectometry and frequency domain reflectometry methods performed best (P = <0.0001; ρ c = >0.76). Sensors using the electrical conductivity method were highly variable in cost, accuracy, and precision. Future work on these sensors may include field performance evaluations as well as management implications for urban sites. [ABSTRACT FROM AUTHOR]

Total dissolved solids (TDS) concentrations in groundwater tapped for beneficial uses (drinking water, irrigation, freshwater industrial) have increased on average by about 100 mg/L over the last 100 years in the San Joaquin Valley, California (SJV). During this period land use in the SJV changed from natural vegetation and dryland agriculture to dominantly irrigated agriculture with growing urban areas. Century-scale salinity trends were evaluated by comparing TDS concentrations and major ion compositions of groundwater from wells sampled in 1910 (Historic) to data from wells sampled in 1993–2015 (Modern). TDS concentrations in subregions of the SJV, the southern (SSJV), western (WSJV), northeastern (NESJV), and southeastern (SESJV) were calculated using a cell-declustering method. TDS concentrations increased in all regions, with the greatest increases found in the SSJV and SESJV. Evaluation of the Modern data from the NESJV and SESJV found higher TDS concentrations in recently recharged (post-1950) groundwater from shallow (<50 m) wells surrounded predominantly by agricultural land uses, while premodern (pre-1950) groundwater from deeper wells, and recently recharged groundwater from wells surrounded by mainly urban, natural, and mixed land uses had lower TDS concentrations, approaching the TDS concentrations in the Historic groundwater. For the NESJV and SESJV, inverse geochemical modeling with PHREEQC indicated that weathering of primary silicate minerals accounted for the majority of the increase in TDS concentrations, contributing more than nitrate from fertilizers and sulfate from soil amendments combined. Bicarbonate showed the greatest increase among major ions, resulting from enhanced silicate weathering due to recharge of irrigation water enriched in CO 2 during the growing season. The results of this study demonstrate that large anthropogenic changes to the hydrologic regime, like massive development of irrigated agriculture in semi-arid areas like the SJV, can cause large changes in groundwater quality on a regional scale. [ABSTRACT FROM AUTHOR]

Subcutaneous long-acting release (LAR) formulations have been extensively developed in the clinic to increase patient compliance and reduce treatment cost. Despite preliminary success for some LAR systems, a major obstacle limiting the therapeutic effect remains on their interaction with surrounding tissues. In this review, we summarize how living bodies respond to injected or implanted materials, and highlight some typical strategies based on smart material design, which may significantly improve long-term subcutaneous drug delivery. Moreover, possible strategies to achieve ultra-long (months, years) subcutaneous drug delivery systems are proposed. Based on these discussions, we believe the well-designed subcutaneous long-acting formulations will hold great promise to improve patient quality of life in the clinic. [ABSTRACT FROM AUTHOR]

Urban trees experience site-induced stress and this leads to reduced growth and health. A site assessment tool would be useful for urban forest managers to better match species tolerances and site qualities, and to assess the efficacy of soil management actions. Toward this goal, a rapid urban site index (RUSI) model was created and tested for its ability to predict urban tree performance. The RUSI model is field-based assessment tool that scores 15 parameters in approximately five minutes. This research was conducted in eight cities throughout the Midwest and Northeast USA to test the efficacy of the RUSI model. The RUSI model accurately predicted urban tree health and growth metrics ( P < 0.0001; R 2 0.18–0.40). While the RUSI model did not accurately predict mean diameter growth, it was significantly correlated with recent diameter growth. Certain parameters in the RUSI model, such as estimated rooting area, soil structure and aggregate stability appeared to be more important than other parameters, such as growing degree days. Minimal improvements in the RUSI model were achieved by adding soil laboratory analyses. Field assessments in the RUSI model were significantly correlated with similar laboratory analyses. Other users may be able to use the RUSI model to assess urban tree planting sites (<5 min per site and no laboratory analyses fee), but training will be required to accurately utilize the model. Future work on the RUSI model will include developing training modules and testing across a wider geographic area with more urban tree species and urban sites. [ABSTRACT FROM AUTHOR]

It is demonstrated that carboxylic acid-functionalized titanium dioxide (TiO 2 ) NPs produce significantly higher levels of reactive oxygen species (ROS) after visible light irradiation (400–800 nm, 1600 mW/cm 2 ) in comparison to nonfunctionalized TiO 2 NPs. The level of ROS produced under these irradiation conditions was not capable of generating oxidatively induced DNA damage in a cell-free system for TiO 2 concentrations of 0.5 mg/L or 5 mg/L. In addition, specific incorporation of the acrylic acid-functionalized TiO 2 NPs into dental composites allowed us to utilize the generated ROS to enhance photopolymerization (curing and degree of vinyl conversion (DC)) of resin adhesives and create mechanically superior and biocompatible materials for dental applications. Incorporation of the TiO 2 NPs into selected dental composites increased the mean DC values by ≈7%. The modified TiO 2 materials and dental composite materials were extensively characterized using thermogravimetric analysis, electron microscopy, Fourier transform infrared spectroscopy, and electron paramagnetic resonance. Notably, dental adhesives incorporated with acrylic acid-functionalized TiO 2 NPs produced stronger bonds to human teeth following visible light curing in comparison to traditional dental adhesives not containing NPs with an increase in the shear bond strength of ≈29%. In addition, no leaching of the incorporated NPs was detectable from the dental adhesives after 2500 thermal cycles using inductively coupled plasma-optical emission spectroscopy, indicating that biocompatibility of the adhesives was not compromised after extensive aging. These findings suggest that NP-induced ROS may be useful to produce enhanced nanocomposite materials for selected applications in the medical device field. Statement of Significance Titanium dioxide nanoparticles (TiO 2 NPs) have unique photocatalytic, antibacterial and UV-absorbing properties that make them beneficial additives in adhesives and composites. However, there is concern that the reactive oxygen species (ROS) produced by photoactivated TiO 2 NPs might pose toxicological risks. We demonstrate that it is possible to incorporate acid-functionalized TiO 2 NPs into dental resins which can be applied as dental adhesives to human teeth. The ROS generated by these NPs through visible-light irradiation may be utilized to increase the degree of vinyl conversion of resins, leading to adhesives that have an enhanced shear-bond strength to human teeth. Investigation into the potential genotoxicity of the NPs and their potential for release from dental composites indicated a low risk of genotoxic effects. [ABSTRACT FROM AUTHOR]

Citizen science has been gaining popularity in ecological research and resource management in general and in urban forestry specifically. As municipalities and nonprofits engage volunteers in tree data collection, it is critical to understand data quality. We investigated observation error by comparing street tree data collected by experts to data collected by less experienced field crews in Lombard, IL; Grand Rapids, MI; Philadelphia, PA; and Malmö, Sweden. Participants occasionally missed trees (1.2%) or counted extra trees (1.0%). Participants were approximately 90% consistent with experts for site type, land use, dieback, and genus identification. Within correct genera, participants recorded species consistent with experts for 84.8% of trees. Mortality status was highly consistent (99.8% of live trees correctly reported as such), however, there were few standing dead trees overall to evaluate this issue. Crown transparency and wood condition had the poorest performance and participants expressed concerns with these variables; we conclude that these variables should be dropped from future citizen science projects. In measuring diameter at breast height (DBH), participants had challenges with multi-stemmed trees. For single-stem trees, DBH measured by participants matched expert values exactly for 20.2% of trees, within 0.254 cm for 54.4%, and within 2.54 cm for 93.3%. Participants’ DBH values were slightly larger than expert DBH on average (+0.33 cm), indicating systematic bias. Volunteer data collection may be a viable option for some urban forest management and research needs, particularly if genus-level identification and DBH at coarse precision are acceptable. To promote greater consistency among field crews, we suggest techniques to encourage consistent population counts, using simpler methods for multi-stemmed trees, providing more resources for species identification, and more photo examples for other variables. Citizen science urban forest inventory and monitoring projects should use data validation and quality assurance procedures to enhance and document data quality. [ABSTRACT FROM AUTHOR]

Soil is the largest pool of organic carbon in terrestrial systems and plays a key role in carbon cycle. Global population living in urban areas are increasing substantially; however, the effects of urbanization on soil carbon storage and distribution are largely unknown. Here, we characterized the soil organic carbon (SOC) in roadside soils across the city-state of Singapore. We tested three hypotheses that SOC contents (concentration and density) in Singapore would be positively related to aboveground tree biomass, soil microbial biomass and land-use patterns. Overall mean SOC concentrations and densities (0–100 cm) of Singapore's roadside soils were 29 g kg −1 (4–106 g kg −1 ) and 11 kg m −2 (1.1–42.5 kg m −2 ) with median values of 26 g kg −1 and 10 kg m −2 , respectively. There was significantly higher concentration of organic carbon (10.3 g kg −1 ) in the top 0–30 cm soil depth compared to the deeper (30–50 cm, and 50–100 cm) soil depths. Singapore's roadside soils represent 4% of Singapore's land, but store 2.9 million Mg C (estimated range of 0.3–11 million Mg C). This amount of SOC is equivalent to 25% of annual anthropogenic C emissions in Singapore. Soil organic C contents in Singapore's soils were not related to aboveground vegetation or soil microbial biomass, whereas land-use patterns to best explain variance in SOC in Singapore's roadside soils. We found SOC in Singapore's roadside soils to be inversely related to urbanization. We conclude that high SOC in Singapore roadside soils are probably due to management, such as specifications of high quality top-soil, high use of irrigation and fertilization and also due to an optimal climate promoting rapid growth and biological activity. [ABSTRACT FROM AUTHOR]

Peripheral vasculopathies cause severe wound hypoxia inducing the hypoxamiR miR-210. High level of miR-210, persisting in wound-edge tissue as ischemic memory, suppresses oxidative metabolism and inhibits cell proliferation necessary for healing. In wound-edge tissue of chronic wound patients, elevated miR-210 was tightly associated with inhibition of epidermal cell proliferation as evident by lowered Ki67 immunoreactivity. To inhibit miR-210 in murine ischemic wound-edge tissue, we report the formulation of antihypoxamiR functionalized gramicidin lipid nanoparticles (AFGLN). A single intradermal delivery of AFGLN encapsulating LNA-conjugated anti-hypoximiR-210 (AFGLN miR-210 ) lowered miR-210 level in the ischemic wound-edge tissue. In rep TOP™ mito IRE mice, AFGLN miR-210 rescued keratinocyte proliferation as visualized by in vivo imaging system (IVIS). 31 P NMR studies showed elevated ATP content at the ischemic wound-edge tissue following AFGLN miR-210 treatment indicating recovering bioenergetics necessary for healing. Consistently, AFGLN miR-210 improved ischemic wound closure. The nanoparticle based approach reported herein is effective for miR-directed wound therapeutics warranting further translational development. [ABSTRACT FROM AUTHOR]

Urban forests are recognized as a nature-based solution for stormwater management. This study assessed the underlying processes and extent of runoff reduction due to street trees with a paired-catchment experiment conducted in two sewersheds of Fond du Lac, Wisconsin. Computer models are flexible, fast, and low-cost options to generalize and assess the hydrologic processes determined in field studies. A state-of-the-art, public-domain model, which explicitly simulates urban tree hydrology, i-Tree Hydro, was used to simulate the paired-catchment experiment, and results from field observations and simulation predictions were compared to assess model validity and suitability as per conditions in the broader Great Lakes basin. Model parameters were aligned with observed conditions using automatic and manual calibration. Model performance metrics were used to quantify the weekly performance of calibration and to validate predictions. Those calibration metrics differed substantially between the two periods simulated, but most calibration metrics remained positive, indicating the model was not fitting only the period used for calibration. Predicted avoided runoff for a five-month leaf-on period was 64 L/m2 of canopy, 4 % lower than the field-estimated avoided runoff of 66 L/m2 of canopy. Interception was the most directly comparable process between the model and field observations. Based on 5 storms sampled, field estimation of precipitation intercepted and retained on trees averaged 63 % and ranged from 22 % to 81 %, while model estimation averaged 61 % and ranged from 36 % to 99 %. This model was able to fit predictions to observed catchment discharge but required extensive manual calibration to do so. The i-Tree Hydro model predicted avoided runoff comparable with the field study and earlier assessments. Additional field studies in similar settings are needed to confirm findings and improve transferability to other tree species and environmental settings. [ABSTRACT FROM AUTHOR]

Digital volume correlation (DVC) provides experimental measurements of displacements and strains throughout the interior of porous materials such as trabecular bone. It can provide full-field continuum-and tissue-level measurements, desirable for validation of finite element models, by comparing image volumes from subsequent mCT scans of a sample in unloaded and loaded states. Since the first application of DVC for measurement of strain in bone tissue, subsequent reports of its application to trabecular bone cores up to whole bones have appeared within the literature. An "optimal" set of procedures capable of precise and accurate measurements of strain, however, still remains unclear, and a systematic review focussing explicitly on the increasing number of DVC algorithms applied to bone or structurally similar materials is currently unavailable. This review investigates the effects of individual parameters reported within individual studies, allowing to make recommendations for suggesting algorithms capable of achieving high accuracy and precision in displacement and strain measurements. These recommendations suggest use of subsets that are sufficiently large to encompass unique datasets (e.g. subsets of 500 mm edge length when applied to human trabecular bone cores, such as cores 10 mm in height and 5 mm in diameter, scanned at 15 mm voxel size), a shape function that uses full affine transformations (translation, rotation, normal strain and shear strain), the robust normalized cross-correlation coefficient objective function, and high-order interpolation schemes. As these employ computationally burdensome algorithms, researchers need to determine whether they have the necessary computational resources or time to adopt such strategies. As each algorithm is suitable for parallel programming however, the adoption of high precision techniques may become more prevalent in the future. [ABSTRACT FROM AUTHOR]

Fire suppression policies and "active management" in response to wildfires are being carried out by land managers globally, including millions of hectares of mixed conifer and dry ponderosa pine (Pinus ponderosa) forests of the western USA that periodically burn in mixed severity fires. Federal managers pour billions of dollars into command-and-control fire suppression and the MegaFire (landscape scale) Active Management Approach (MFAMA) in an attempt to contain wildfires increasingly influenced by top down climate forcings. Wildfire suppression activities aimed at stopping or slowing fires include expansive dozerlines, chemical retardants and igniters, backburns, and cutting trees (live and dead), including within roadless and wilderness areas. MFAMA involves logging of large, fire-resistant live trees and snags; mastication of beneficial shrubs; degradation of wildlife habitat, including endangered species habitat; aquatic impacts from an expansive road system; and logging-related carbon emissions. Such impacts are routinely dismissed with minimal environmental review and defiance of the precautionary principle in environmental planning. Placing restrictive bounds on these activities, deemed increasingly ineffective in a change climate, is urgently needed to overcome their contributions to the global biodiversity and climate crises. We urge land managers and decision makers to address the root cause of recent fire increases by reducing greenhouse gas emissions across all sectors, reforming industrial forestry and fire suppression practices, protecting carbon stores in large trees and recently burned forests, working with wildfire for ecosystem benefits using minimum suppression tactics when fire is not threatening towns, and surgical application of thinning and prescribed fire nearest homes. • Massive fire suppression and "active management" are damaging to fire-adapted forests. • Environmental laws and protected areas are at risk from expansive logging. • Federal agencies pour billions of dollars annually into command-and-control tactics. • A growing divide exists between biodiversity and many "fuel reduction" approaches. • Addressing root causes means solving for the climate and biodiversity crises. [ABSTRACT FROM AUTHOR]

Abstract: We aimed to find out whether improved preoperative assessment and surgical planning with cone beam computed tomography (CT) could reduce damage to the inferior alveolar nerve when high risk impacted mandibular third molars are extracted. We recorded the presence or absence of postoperative neuropathy after extraction of 200 lower third molars in 185 patients (where cone beam CT had shown contact between the nerve and root) after treatment in the oral surgery department of King''s College Hospital. All patients had had cone beam CT of the teeth after panoramic radiography had indicated increased risk of injury to the nerve during extraction. Experienced oral surgeons did all the operations and postoperative reviews. Patients reported temporary alteration of sensation after operation in 12% of teeth but it resolved in all cases and no patient reported permanent loss of sensation. Permanent sensory disturbance in the distribution of the inferior alveolar nerve after third molars have been removed can be eliminated in high risk cases if operations are planned carefully (including cone beam CT), and the procedure is done by a skilled surgeon who has an appreciation of the anatomy of the nerve and roots, and an insight into the mechanical effect of their surgical manipulation. The incidence of permanent neurosensory dysfunction in this study was zero even though all teeth were intimately related to the inferior alveolar canal. [Copyright &y& Elsevier]

Abstract: We report on the development of a protease biosensing platform using novel high surface area nanoporous organosilicate (NPO) thin film supports. NPO films, with their three dimensional interconnected pores are constituted of organosilicate nanoparticles and are characterized by their large and accessible surface areas, ideal for high density binding of biological probes. Here, we demonstrate enhanced protease sensing of a serine protease, trypsin using a Forster resonance energy transfer (FRET) assay performed on the NPO films. Dual fluorescent dye labeled peptide sequences specific to proteolytic activity of trypsin were used as the sensor probes and immobilized with high density on the NPO surfaces. Enzymatic activity of trypsin was monitored by measuring the donor to acceptor fluorescence ratio changes as a function of both reaction time (time response) and trypsin concentration (dose response). Performance of the same assay on planar glass substrates yielded inconclusive results owing to the inherently low signal/noise ratio from these substrates and potential unfavorable orientation of peptides toward trypsin. Using NPO films, a detection limit of 2.45μg/ml was achieved in 14min. The use of solid supports for the performance of protease assays is expected to significantly miniaturize the assays and aid in multiplexing akin to antibody based microarrays. [Copyright &y& Elsevier]

Abstract: Human serum albumin (HSA)-coated lipid nanoparticles (HSA-LNPs) loaded with phrGFP-targeted siRNA (HSA-LNPs-siRNA) were prepared and evaluated for gene downregulation effect in phrGFP-transfected breast cancer cells and the corresponding xenograft tumor model. HSA-LNPs-siRNA were successfully prepared with a particle size of 79.5±5.5 nm. In phrGFP-transfected MCF-7 cells, HSA-LNPs-siRNA significantly decreased cell fluorescence even in the presence of fetal bovine serum (FBS). Moreover, cell fluorescence and phrGFP mRNA expression were significantly downregulated by HSA-LNPs-siRNA in phrGFP-transfected MCF-7, MDA-MB-231, and SK-BR-3 cells in comparison with control or HSA-LNPs-siRNA (scrambled). In phrGFP-transfected MCF-7 xenograft tumor model, tumor fluorescence was significantly decreased after three IV administrations of HSA-LNPs-siRNA at a dose of 3 mg/kg in comparison with siRNA alone. HSA-LNPs-siRNA demonstrated a superior pharmacokinetic profile in comparison with siRNA at a dose of 1mg/kg. These results show that the novel nonviral carrier, HSA-LNPs, may be used for the delivery of siRNA to breast cancer cells. From the Clinical Editor: Targeted delivery of siRNA to cancer cells may be a viable anti-cancer strategy with low toxicity. In this study the novel nonviral carrier, human serum albumin-coated lipid nanoparticles (HSA-LNP) were demonstrated as an efficient delivery agent of siRNA to breast cancer cells. [Copyright &y& Elsevier]

Abstract: Tylophorine and many related phenanthropiperidine alkaloids are extraordinarily potent anti-proliferative agents. Despite their impressive anti-cancer activity, clinical development of these alkaloids has been hampered by their poor solubility and neurological side effects. Although it has been suggested that developing polar phenanthropiperidines will mitigate these undesired properties, the lack of practical methods for the synthesis of such analogues has limited this effort. Here, we present a concise synthetic approach to N-substituted phenanthropiperidines, which enabled a systematic investigation of structure-activity relationships at an underexplored region of the tylophorine scaffold. This work suggests that ring E of tylophorine is essential for the anti-proliferative activity of the 6,7,10,11-tetramethoxy-1,2,3,4-tetrahydrodibenzo[f,h]isoquinoline core scaffold. [Copyright &y& Elsevier]

Abstract: Age-related changes have been documented in regions of the brain shown to process reward information. However, few studies have examined the effects of aging on associative memory for reward. The present study tested 7- and 24-month-old rats on a conditioned flavor preference task. Half of the rats in each age group received an unsweetened grape-flavored solution (CS−) on odd-numbered days and a sweetened cherry-flavored solution (CS+) on even-numbered days. The remaining rats in each age group received a sweetened grape-flavored solution (CS+) on odd-numbered days and an unsweetened cherry-flavored solution (CS−) on even-numbered days. During the acquisition phase of testing, the designated solution (CS+ or CS−) was presented to each rat for 15min daily across six consecutive days. On the preference phase, each rat received unsweetened cherry and unsweetened grape-flavored solutions simultaneously for 15min daily across four consecutive days. The 7-month-old rats showed a significant preference for the flavor that was previously sweetened during the acquisition phase (CS+) compared to the previously unsweetened solution (CS−) when the two unsweetened solutions were presented simultaneously during the preference phase of testing. In contrast, the 24-month-old rats did not show a preference and consumed roughly equal amounts of the previously sweetened (CS+) and unsweetened (CS−) solutions. Thus, the data suggest that the ability to form flavor–reward associations declines with increasing age, resulting in impaired conditioned flavor preference. [Copyright &y& Elsevier]

Abstract: Measurements of aerosol optical properties, size distribution and chemical composition were conducted at Finokalia, a remote coastal site on the Greek island of Crete (35°19′N, 25°40′E) during July 2000 and January 2001. During the summer campaign the total scattering coefficient, , (at a wavelength of 550nm) ranged from 13 to 120Mm−1 (mean=44.2Mm−1, standard deviation=17.5) whilst during the winter it ranged from 7.22 to 37.8Mm−1 (mean=18.42Mm−1, standard deviation=6.61). A distinct diurnal variation in scattering coefficients was observed, with minima occurring during the early morning and maxima in the late afternoon during the summer and late evening during the winter. The mean value of the Ångström exponent was 1.47 during the summer and 1.28 during the winter, suggesting a larger fraction of smaller particles at the site during the summer. This was confirmed by continuous measurements of the aerosol size distribution. An analysis of the single scattering albedo suggests that there is a more absorbing fraction in the particle composition in the summer than during the winter. An investigation of air mass origins on aerosol optical properties indicated that those from Turkey and Central/Eastern Europe were highly polluted with a corresponding impact on aerosol optical properties. A linear relationship was obtained between the total scattering coefficient and both the non-sea-salt sulphate concentrations and the fine aerosol fraction. [Copyright &y& Elsevier]

Summary: Modifications associated with urban infrastructure directly impact soil properties. In particular, soil bulk density, microbial biomass and activity, and organic matter are impacted by anthropogenic activities. We proposed that urban soil properties are not only distinguishable from other systems, but also variable within types of landscapes in urban environments. We found soils from older urban landscapes (mean landscape age of 64 years) to be distinct from newer urban landscapes (mean landscape age of 9 years). Soil bulk densities were significantly greater in newer (1.73gcm−3) compared to older urban soils (1.41gcm−3). Older urban soils had significantly greater extractable phosphorous, weak Bray P (24%), strong Bray P (51%), and K (45%) than newer urban soils. Soil biological measures of nitrogen availability were significantly greater in old compared to new urban soils, microbial biomass N (71%), potential C mineralization (20%), and potential N mineralization (83%). We found exponentially decreasing metabolic quotient values, qCO2, suggesting the impact of site disturbance decreases rapidly with time, and older urban landscapes are closer to steady-state conditions relative to younger urban landscapes. Total soil organic matter was significantly greater (35%) in old urban soils. Fine POM was a larger contributor to total SOM in old compared to new urban soils. Particulate organic matter C/N ratios from older urban soils were less (coarse POM 14% less and fine POM 13% less) than newer urban soils. Of the soil forming factors, time played the most significant role in soil physical, chemical, and biological differences. We believe that as time since initial disturbance increases, the impacts of urbanization are reduced by processes improving physical, biological, and chemical soil properties. [Copyright &y& Elsevier]

Since December 2019, COVID-19, the clinical syndrome associated with SARS-CoV-2 infection, has infected more than 6.2 million people and brought the function of the global community to a halt. As the number of patients recovered from COVID-19 rises and the world transitions toward reopening, the question of acquired immunity versus the possibility of reinfection are critical to anticipating future viral spread. Here, we present a case of a patient previously recovered from COVID-19 who re-presents with new respiratory, radiographical, laboratory, and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) findings concerning for possible re-infection. We review this case in the context of the evolving discussion and theories surrounding dynamic RT-PCR results, prolonged viral shedding, and the possibility of developed immunity. Understanding how to interpret dynamic and late-positive SARS-CoV-2 RT-PCR results after primary infection will be critical for understanding disease prevalence and spread among communities worldwide. [ABSTRACT FROM AUTHOR]