Taxonomic insights from floral scents of western North American sessile-flowered Trillium.

PREMISE: Chemical composition of floral volatiles can be an important complement to morphological characters in describing and identifying species. Four of the five species of western sessile-flowered Trillium are challenging to distinguish morphologically due to wide intraspecific variation and overlapping characters among taxa. Characterizing their floral volatile compositions could aid future taxonomic, ecological, and evolutionary studies of Trillium and related taxa. We addressed two major questions: How do western sessile Trillium taxa vary in floral chemistry? Can floral scent be used to distinguish species? METHODS: We collected petals from 600 individuals at 42 wild populations of four sessile Trillium species across California, Oregon, and Washington. Volatile organic compounds from the petals were extracted using solid-phase microextraction, and the volatiles were identified and quantified by gas chromatography-mass spectrometry. The utility of floral scent composition in distinguishing species was tested using nonmetric multidimensional scaling and random forest analysis. RESULTS: Floral volatiles of the white-petaled T. albidum were dominated by oxygenated monoterpenes and showed considerable geographic variation that paralleled morphological variation. The maroon-petaled T. angustipetalum and T. kurabayashii produced floral scents characterized by aliphatic esters, but each had a distinct chemical composition. Petal color of Trillium chloropetalum is highly variable, as were its scent compositions, which were blends of volatiles from both white-petaled and maroon-petaled congeneric taxa. CONCLUSIONS: Differences in floral scent compositions are consistent with current taxonomy of the western sessile Trillium group. In cases where species delimitations are difficult based on morphology, floral scent composition provides taxonomic insight and suggests a potential hybrid origin for T. chloropetalum.

Association of Nicotine Cessation Time on the Incidence of Recurrent Incisional Hernia Repair and Postoperative Surgical Site Occurrences.

BACKGROUND: Nicotine products are believed to be associated with a higher incidence of incisional hernia (IH) recurrence and postoperative complications after IH repair. METHODS: A retrospective analysis of the Abdominal Core Health Quality Collaborative (ACHQC) database was performed. Outcomes included risk of IH recurrence, 30-day surgical site infection (SSI), and 30-day surgical site occurrence (SSO). RESULTS: We included 14,663 patients. Nicotine users who quit within 1 year of surgery had a 26% higher risk of IH recurrence compared to patients who quit more than a year before surgery or never users. Patients who quit using nicotine within 1 year of surgery had a 54% higher odds of SSI compared to former nicotine users who quit more than a year before surgery. CONCLUSION: Former nicotine users with less than 1 year of nicotine use cessation before surgery exhibited worse outcomes than those with more than a year of cessation or no prior use.

Too hot, too cold, or just right: Can wildfire restore dry forests of the interior Pacific Northwest?

As contemporary wildfire activity intensifies across the western United States, there is increasing recognition that a variety of forest management activities are necessary to restore ecosystem function and reduce wildfire hazard in dry forests. However, the pace and scale of current, active forest management is insufficient to address restoration needs. Managed wildfire and landscape-scale prescribed burns hold potential to achieve broad-scale goals but may not achieve desired outcomes where fire severity is too high or too low. To explore the potential for fire alone to restore dry forests, we developed a novel method to predict the range of fire severities most likely to restore historical forest basal area, density, and species composition in forests across eastern Oregon. First, we developed probabilistic tree mortality models for 24 species based on tree characteristics and remotely sensed fire severity from burned field plots. We applied these estimates to unburned stands in four national forests to predict post-fire conditions using multi-scale modeling in a Monte Carlo framework. We compared these results to historical reconstructions to identify fire severities with the highest restoration potential. Generally, we found basal area and density targets could be achieved by a relatively narrow range of moderate-severity fire (roughly 365-560 RdNBR). However, single fire events did not restore species composition in forests that were historically maintained by frequent, low-severity fire. Restorative fire severity ranges for stand basal area and density were strikingly similar for ponderosa pine (Pinus ponderosa) and dry mixed-conifer forests across a broad geographic range, in part due to relatively high fire tolerance of large grand (Abies grandis) and white fir (Abies concolor). Our results suggest historical forest conditions created by recurrent fire are not readily restored by single fires and landscapes have likely passed thresholds that preclude the effectiveness of managed wildfire alone as a restoration tool.

A quantitative analysis of MDMA seized at New South Wales music festivals over the 2019/2020 season: Form, purity, dose and adulterants.

INTRODUCTION: This research aims to understand the content and nature, and to explore the harm potential, of suspected 3,4-methylenedioxymethamphetamine (MDMA) substances circulating at music festivals in New South Wales. METHODS: Across 19 music festivals held between October 2019 and March 2020, 302 substances detected and suspected by police to contain MDMA were selected for quantitative analysis. RESULTS: Five percent of substances contained a drug other than MDMA (n = 13) or no drug (n = 2). The remaining 95.0% (n = 287) contained MDMA. Of this sub-sample, capsule was the commonest form (83.3%), followed by tablet (7.7%), crystal (6.3%) and powder (2.8%). The median MDMA base-purity of non-tablet forms ranged between 73.5% and 75.0%. The median MDMA base-dose per tablet (116 mg) was higher than per capsule (68 mg). The dose range varied substantially for capsules (14-146 mg) and tablets (24-201 mg). A higher dose (130 mg or greater) was found in 3.5% of MDMA tablets or capsules. Adulterants were identified in 14.1% of MDMA substances but only 1.6% contained a psychoactive adulterant and none presented as dangerous due to their nature or low concentration. DISCUSSION AND CONCLUSIONS: Dangerous MDMA adulterants or new psychoactive substances in tablet, capsule, powder or crystal forms (whether misrepresented as MDMA or not) were unlikely to be in circulation during the study period. Harm reduction messaging should inform that a key risk-factor for MDMA-related harm is the high and wide variation of purity and dose across forms. Market changes may have occurred since COVID-19, but continued monitoring will ensure messaging remains current.

The complexity of biological disturbance agents, fuels heterogeneity, and fire in coniferous forests of the western United States.

Forest biological disturbance agents (BDAs) are insects, pathogens, and parasitic plants that affect tree decline, mortality, and forest ecosystems processes. BDAs are commonly thought to increase the likelihood and severity of fire by converting live standing trees to more flammable, dead and downed fuel. However, recent research indicates that BDAs do not necessarily increase, and can reduce, the likelihood or severity of fire. This has led to confusion regarding the role of BDAs in influencing fuels and fire in fire-prone western United States forests. Here, we review the existing literature on BDAs and their effects on fuels and fire in the western US and develop a conceptual framework to better understand the complex relationships between BDAs, fuels and fire. We ask: 1) What are the major BDA groups in western US forests that affect fuels? and 2) How do BDA-affected fuels influence fire risk and outcomes? The conceptual framework is rooted in the spatiotemporal aspects of BDA life histories, which drive forest impacts, fuel characteristics and if ignited, fire outcomes. Life histories vary among BDAs from episodic, landscape-scale outbreaks (bark beetles, defoliators), to chronic, localized disturbance effects (dwarf mistletoes, root rots). Generally, BDAs convert aboveground live biomass to dead biomass, decreasing canopy fuels and increasing surface fuels. However, the rate of conversion varies with time-since-event and among BDAs and forest types, resulting in a wide range of effects on the amount of dead fuels at any given time and place, which interacts with the structure and composition of the stand before and subsequent to BDA events. A major influence on fuels may be that BDAs have emerged as dominant agents of forest heterogeneity creation. Because BDAs play complex roles in fuels and fire heterogeneity across the western US which are further complicated by interactions with climate change, drought, and forest management (fire suppression), their impacts on fuels, fire and ecological consequences cannot be categorized simply as positive or negative but need to be evaluated within the context of BDA life histories and ecosystem dynamics.

An Ecological Perspective on Living with Fire in Ponderosa Pine Forests of Oregon and Washington: Resistance, Gone but not Forgotten.

Wildland fires (WLF) have become more frequent, larger, and severe with greater impacts to society and ecosystems and dramatic increases in firefighting costs. Forests throughout the range of ponderosa pine in Oregon and Washington are jeopardized by the interaction of anomalously dense forest structure, a warming and drying climate, and an expanding human population. These forests evolved with frequent interacting disturbances including low-severity surface fires, droughts, and biological disturbance agents (BDAs). Chronic low-severity disturbances were, and still are, critical to maintaining disturbance resistance, the property of an ecosystem to withstand disturbance while maintaining its structure and ecological function. Restoration of that historical resistance offers multiple social and ecological benefits. Moving forward, we need a shared understanding of the ecology of ponderosa pine forests to appreciate how restoring resistance can reduce the impacts of disturbances. Given contemporary forest conditions, a warming climate, and growing human populations, we predict continued elevation of tree mortality from drought, BDAs, and the large high-severity WLFs that threaten lives and property as well as ecosystem functions and services. We recommend more comprehensive planning to promote greater use of prescribed fire and management of reported fires for ecological benefits, plus increased responsibility and preparedness of local agencies, communities and individual homeowners for WLF and smoke events. Ultimately, by more effectively preparing for fire in the wildland urban interface, and by increasing the resistance of ponderosa pine forests, we can greatly enhance our ability to live with fire and other disturbances.

Selected conditions associated with an increased incidence of incisional hernia: A review of molecular biology.

BACKGROUND: Incisional hernias (IH) following a laparotomy, on average, occur in 10-20% of patients, however, little is known about its molecular basis. Thus, a better understanding of the molecular mechanisms could lead to the identification of key target(s) to intervene pre-and post-operatively. METHODS: We examined the current literature describing the molecular mechanisms of IH and overlap these factors with smoking, abdominal aortic aneurysm, obesity, diabetes mellitus, and diverticulitis. RESULTS: The expression levels of collagen I and III, matrix metalloproteinases, and tissue inhibitors of metalloproteases are abnormal in the extracellular matrix (ECM) of IH patients and ECM disorganization has an overlap with these comorbid conditions. CONCLUSION: Understanding the pathophysiology of IH development and associated risk factors will allow physicians to identify patients that may be at increased risk for IH and to possibly act preemptively to decrease the incidence of IH.

Cytoreduction with hyperthermic intra peritoneal and intra thoracic chemotherapy for metastatic Sertoli-Leydig cell tumor of the ovary.

Sertoli Leydig cell tumor (SLCT) is a rare sex-cord stromal tumor of the ovary that generally has a benign course. Here, we report an unusual case of recurrent, metastatic SLCT and its unique management with a combination of cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, hyperthermic intrathoracic chemotherapy, and systemic chemotherapy.

Corralling a black swan: natural range of variation in a forest landscape driven by rare, extreme events.

The natural range of variation (NRV) is an important reference for ecosystem management, but has been scarcely quantified for forest landscapes driven by infrequent, severe disturbances. Extreme events such as large, stand-replacing wildfires at multi-century intervals are typical for these regimes; however, data on their characteristics are inherently scarce, and, for land management, these events are commonly considered too large and unpredictable to integrate into planning efforts (the proverbial "Black Swan"). Here, we estimate the NRV of late-seral (mature/old-growth) and early-seral (post-disturbance, pre-canopy-closure) conditions in a forest landscape driven by episodic, large, stand-replacing wildfires: the Western Cascade Range of Washington, USA (2.7 million ha). These two seral stages are focal points for conservation and restoration objectives in many regions. Using a state-and-transition simulation approach incorporating uncertainty, we assess the degree to which NRV estimates differ under a broad range of literature-derived inputs regarding (1) overall fire rotations and (2) how fire area is distributed through time, as relatively frequent smaller events (less episodic), or fewer but larger events (more episodic). All combinations of literature-derived fire rotations and temporal distributions (i.e., "scenarios") indicate that the largest wildfire events (or episodes) burned up to 105 -106  ha. Under most scenarios, wildfire dynamics produced 5th-95th percentile ranges for late-seral forests of ~47-90% of the region (median 70%), with structurally complex early-seral conditions composing ~1-30% (median 6%). Fire rotation was the main determinant of NRV, but temporal distribution was also important, with more episodic (temporally clustered) fire yielding wider NRV. In smaller landscapes (20,000 ha; typical of conservation reserves and management districts), ranges were 0-100% because fires commonly exceeded the landscape size. Current conditions are outside the estimated NRV, with the majority of the region instead covered by dense mid-seral forests (i.e., a regional landscape with no historical analog). Broad consistency in NRV estimates among widely varied fire regime parameters suggests these ranges are likely relevant even under changing climatic conditions, both historical and future. These results indicate management-relevant NRV estimates can be derived for seral stages of interest in extreme-event landscapes, even when incorporating inherent uncertainties in disturbance regimes.

Novel understanding of high mobility group box-1 in the immunopathogenesis of incisional hernias.

Introduction: Incisional hernias (IH) arise as a complication of patients undergoing laparotomy. Current literature has assessed the role of extracellular matrix (ECM) disorganization, alterations in type I and type III collagen, matrix metalloproteinases, and tissue inhibitors of metalloproteases on IH. However, there is limited information on the underlying molecular mechanisms that lead to ECM disorganization. Areas covered: We critically reviewed the literature surrounding IH and ECM disorganization and offer a novel pathway that may be the underlying mechanism resulting in ECM disorganization and the immunopathogenesis of IH. Expert opinion: High mobility group box-1 (HMGB-1), a damage-associated molecular pattern, plays an important role in the sterile inflammatory pathway and has been linked to ECM disorganization and the triggering of the NLRP3 inflammasome. Further research to investigate the role of HMGB-1 in the molecular pathogenesis of IH would be critical in identifying novel therapeutic targets in the management of IH formation.

Cumulative effects of wildfires on forest dynamics in the eastern Cascade Mountains, USA.

Wildfires pose a unique challenge to conservation in fire-prone regions, yet few studies quantify the cumulative effects of wildfires on forest dynamics (i.e., changes in structural conditions) across landscape and regional scales. We assessed the contribution of wildfire to forest dynamics in the eastern Cascade Mountains, USA from 1985 to 2010 using imputed maps of forest structure (i.e., tree size and canopy cover) and remotely sensed burn severity maps. We addressed three questions: (1) How do dynamics differ between the region as a whole and the unburned portion of the region? (2) How do dynamics vary among vegetation zones differing in biophysical setting and historical fire frequency? (3) How have forest structural conditions changed in a network of late successional reserves (LSRs)? Wildfires affected 10% of forests in the region, but the cumulative effects at this scale were primarily slight losses of closed-canopy conditions and slight gains in open-canopy conditions. In the unburned portion of the region (the remaining 90%), closed-canopy conditions primarily increased despite other concurrent disturbances (e.g., harvest, insects). Although the effects of fire were largely dampened at the regional scale, landscape scale dynamics were far more variable. The warm ponderosa pine and cool mixed conifer zones experienced less fire than the region as a whole despite experiencing the most frequent fire historically. Open-canopy conditions increased slightly in the mixed conifer zone, but declined across the ponderosa pine zone even with wildfires. Wildfires burned 30% of the cold subalpine zone, which experienced the greatest increase in open-canopy conditions and losses of closed-canopy conditions. LSRs were more prone to wildfire than the region as a whole, and experienced slight declines in late seral conditions. Despite losses of late seral conditions, wildfires contributed to some conservation objectives by creating open habitats (e.g., sparse early seral and woodland conditions) that otherwise generally decreased in unburned landscapes despite management efforts to increase landscape diversity. This study demonstrates the potential for wildfires to contribute to regional scale conservation objectives, but implications for management and biodiversity at landscape scales vary geographically among biophysical settings, and are contingent upon historical dynamics and individual species habitat preferences.