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Levels of volatile organic compounds (VOCs) in the indoor environment can be decreased by the use of “air cleaners”, devices that remove VOCs by sorption and/or oxidative degradation. However, effi...

The FORCAsT (FORest Canopy Atmosphere Transfer) model version 1.0 is updated to FORCAsT 2.0 by implementing five major changes, including (1) a change to the operator splitting, separating chemistry from emission and dry deposition, which reduces the run time of the gas-phase chemistry by 70 % and produces a more realistic in-canopy profile for isoprene; (2) a modification of the eddy diffusivity parameterization to produce greater and more realistic vertical mixing in the boundary layer, which ameliorates the unrealistic simulated end-of-day peaks in isoprene under well-mixed conditions and improves daytime air temperature; (3) updates to dry deposition velocities with available measurements; (4) implementation of the Reduced Caltech Isoprene Mechanism (RCIM) to reflect the current knowledge of isoprene oxidation; and (5) extension of the aerosol module to include isoprene-derived secondary organic aerosol (iSOA) formation. Along with the operator splitting, modified vertical mixing, and dry deposition, RCIM improves the estimation of first-generation isoprene oxidation products (methyl vinyl ketone and methacrolein) and some second-generation products (such as isoprene epoxydiols). Inclusion of isoprene in the aerosol module in FORCAsT 2.0 leads to a 7 % mass yield of iSOA. The most important iSOA precursors are IEPOX and tetrafunctionals, which together account for >86 % of total iSOA. The iSOA formed from organic nitrates is more important in the canopy, accounting for 11 % of the total iSOA. The tetrafunctionals compose up to 23 % of the total iSOA formation, highlighting the importance of the fate (i.e., dry deposition and gas-phase chemistry) of later-generation isoprene oxidation products in estimating iSOA formation.

A highly convergent total synthesis of (-)-bastimolide A (1), a polyhydroxy antimalarial macrolide, has been achieved via a longest linear sequence of twenty steps from commercially available glycidyl ethers. Type I Anion Relay Chemistry (ARC) coupling tactics enable rapid construction of the molecule's 1,5-polylol backbone. A late-stage B-alkyl Suzuki-Miyaura union and an Evans-modified Mukaiyama macrolactonization generate the forty-membered Z-α,β-unsaturated macrocyclic lactone.

The development of a concise total synthesis of (±)-phyllantidine (1), a member of the securinega family of alkaloids containing an unusual oxazabicyclo[3.3.1]nonane core, is described. The synthesis employs a unique synthetic strategy featuring the ring expansion of a substituted cyclopentanone to a cyclic hydroxamic acid as a key step that allows facile installation of the embedded nitrogen-oxygen (N-O) bond. The optimization of this sequence to effect the desired regiochemical outcome and its mechanistic underpinnings were assessed both computationally and experimentally. This synthetic approach also features an early-stage diastereoselective aldol reaction to assemble the substituted cyclopentanone, a mild reduction of an amide intermediate without N-O bond cleavage, and the rapid assembly of the butenolide found in (1) via use of the Bestmann ylide.

Sea spray aerosols (SSAs) affect the Earth’s climate directly by scattering solar radiation and indirectly by acting as ice and cloud condensation nuclei. The relative magnitude of these effects remains uncertain, in part, from substantial compositional and morphological variability between individual particles. Here, the evolving heterogeneity within populations of primary SSAs produced from wave breaking of natural seawater within a wave flume is investigated. Over the course of the study, two successive phytoplankton blooms were induced in the seawater. The morphology, organic volume fraction, hygroscopicity, phase state, and surface tension of individual SSAs collected via deposition on a substrate were characterized using atomic force microscopy. Particles between ca. 0.3 and 1 μm in volume equivalent diameter displayed a distinctive morphology revealing an inorganic core coated with an organic shell. The inferred organic volume fraction was the largest at the peak of the first bloom. The corresponding shell thicknesses ranged from 21 to 40 nm at 20% relative humidity (RH). The organic shell phase state of the majority of the particles during both blooms was semisolid at 20% and 60% RH. At 20% RH, a minor fraction of the organic shells behaved as a solid, while at 60% RH some behaved as liquids during the first bloom. Similar results were evident at 20% RH for the second bloom but with no observed liquid particles at 60% RH. The thick, semisolid organic coatings could potentially reduce atmospheric water and gas uptake efficiencies onto SSAs at lower RH, along with the potential for ice nucleating activity. However, at 80% RH, the SSAs deliquesced and exhibited liquid-like behavior with surface tension values measured over individual particles of 41–87 mN m–1, demonstrating high particle-to-particle variability. The suppressed surface tension at 80% RH relative to pure water is attributed to the high concentrations of surface-active organic compounds, potentially further limiting the diffusion rate of gas molecules through the interface.

Longeracemine, a member of the Daphniphyllum family of alkaloids contains a novel carbon framework featuring a highly functionalized 2-azabicyclo[2.2.1]heptane core as part of an overall 5/6/5/5/6/5 skeleton. A synthetic intermediate containing the core of longeracemine has been efficiently prepared by employing a stereoselective SmI2-mediated cascade reaction to advance a 7-azabicyclo[2.2.1]heptadiene to a 2-azabicyclo[2.2.1]heptene that is functionally poised for conversion to the natural product., A synthetic intermediate containing the core of longeracemine, that is functionally poised for conversion to the natural product, has been efficiently prepared by employing a stereoselective SmI2-mediated cascade reaction.

This study examines the relationship between private equity investment and local employment growth. Using a sample of over 3,000 US counties, we estimate the effect of private equity investment volume and demographic determinants of employment growth (labor supply, labor quality, labor cost, unionization, agglomeration, industry concentration, and regional geography) on employment changes from 2011 to 2014. Controlling for these demographic factors, private equity investment shows a positive correlation with employment changes. TOPIC:Private equity Key Findings • The study finds a positive association between private equity investment and employment growth. Results indicate that for each $1 million in additional private equity investment, a little more than 1.3 new jobs are created. • Results imply that private equity investment could create positive externalities. Statistical tests using county-wide employment data suggest that company specific private equity investment job-creation effects spill over from the company receiving financing to the local economy.

The total syntheses of (-)-herquline B (2) and a heretofore-unrecognized congener, (+)-herquline C (3), are described. The syntheses require 14 and 13 steps, respectively, and feature a key oxazoline reduction that sets the stage for piperazine construction.

In-cloud chemistry has important ramifications for atmospheric particulate matter formation and gas-phase chemistry. Recent work has shown that, like hydrogen peroxide (H2O2), the two main isomers of isoprene hydroxyl hydroperoxide (ISOPOOH) oxidize sulfur dioxide dissolved in cloud droplets (SO2,aq) to sulfate. The work revealed that the pathway of SO2,aq oxidation with ISOPOOH differs from that of H2O2. We investigate the chemical mechanisms of oxidation of SO2,aq with ISOPOOH in the cloud-relevant pH range of 3–6 and compare them with the previously reported mechanisms of oxidation of SO2,aq with H2O2, methyl hydroperoxide and peroxyacetic acid. The organic products of the reaction are identified and two pathways are proposed. For 1,2-ISOPOOH, a higher yield pathway via proposed radical intermediates yields methyl vinyl ketone (MVK) and formaldehyde, which can react to hydroxymethanesulfonate (HMS) when SO2,aq is present. A lower yield non-fragmentation oxygen addition pathway is proposed that results in formation of isoprene-derived diols (ISOPOH). Based on global simulations, this mechanism is not a significant pathway for formation of MVK and formaldehyde relative to their gas-phase formation but, as previously reported, it can be regionally important for sulfate production. The study adds to previous work that highlights similarities and differences between gas-phase and cloud-droplet processing of reactive organic carbon.

Model studies to develop a tetracyclization approach mimicking the proposed biosynthesis of the secodaphnane-type alkaloid longeracemine are described. These studies have culminated in the successful implementation of a 3H-pyrrole [4+2] cycloaddition that delivers a longeracemine-like azabicycle containing three contiguous quaternary stereocenters.

Inland lakes, important water resources, play a crucial role in the global water cycle and are sensitive to climate change and human activities. There clearly is a pressing need to understand temporal and spatial variations of lakes at global and continental scales. The recent operation of Landsat 8 extends the unprecedented Landsat record to over 40 years, allowing long-term, large-scale lake dynamics mapping at high resolutions. Using our circa-2000 lake product derived from Landsat 7 images as a reference, this research produces a circa-2015 map of representative lake extents and distributions, and addresses seasonal and inter-annual lake area variability using Landsat 8 images acquired in lake stable seasons at a continental scale. Oceania is chosen here as a case study as it contains a large group of salt lakes that exhibit high area variability and has the most intensive image coverage during the first 2.5-year operation of Landsat 8. Accordingly, this paper describes an adaptive algorithm to automate lake mapping for various surface conditions using images acquired during lake stable seasons and a compositing scheme in the vector domain to generate a representative continental mosaic of lake extents from multi-temporal mapping. Our results demonstrate that these strategies and methods produce a highly reliable and representative composite of highly-variable lake extents across Oceania, and are potentially applicable to other large-scale lake mapping projects using multi-temporal data.

Aromatic hydrocarbons make up a large fraction of anthropogenic volatile organic compounds and contribute significantly to the production of tropospheric ozone and secondary organic aerosol (SOA). A series of toluene and 1,2,4-trimethylbenzene (1,2,4-TMB) photooxidation experiments were performed in an environmental chamber under relevant polluted conditions (NOx ~ 10 ppb). An extensive suite of instrumentation including two Proton-Transfer Reaction Mass-Spectrometers (PTR-MS) and two Chemical Ionization Mass-Spectrometers (NH4+ CIMS and I- CIMS) allowed for quantification of reactive carbon in multiple generations of oxidation. Hydroxyl radical (OH)-initiated oxidation of both species produces ring-retaining products such as cresols, benzaldehydes, and bicyclic intermediate compounds, as well as ring scission products such as epoxides, and dicarbonyls. We show that the oxidation of bicyclic intermediate products leads to formation of compounds with high oxygen content (O:C ratio up to 1.1). These compounds, previously identified as highly oxygenated molecules (HOMs), are produced by more than one pathway with differing numbers of reaction steps with OH, including both autooxidation and phenolic pathways. We report the elemental composition of these compounds formed under relevant urban high-NO conditions. We show that ring-retaining products for these two precursors are more diverse and abundant than predicted by current mechanisms. We present speciated elemental composition of SOA for both precursors and confirm that highly oxygenated products make up a significant fraction of SOA. Ring scission products are also detected in both the gas and particle phases, and their yields and speciation overall agree with the kinetic model prediction.

A proper knowledge of noninvasive facial rejuvenation is integral to the practice of a cosmetic surgeon. Noninvasive facial rejuvenation can be divided into patient- versus physician-directed modalities. Patient-directed facial rejuvenation combines the use of facial products such as sunscreen, moisturizers, retinoids, α-hydroxy acids, and various antioxidants to both maintain youthful skin as well as rejuvenate damaged skin. Physicians may recommend and often prescribe certain products, but patients are in control with this type of facial rejuvenation. On the other hand, physician-directed facial rejuvenation entails modalities that require direct physician involvement, such as neuromodulators, filler injections, laser resurfacing, microdermabrasion, and chemical peels. With the successful integration of each of these modalities, a complete facial regimen can be established and patient satisfaction can be maximized. This article is the second in a three-part series describing noninvasive facial rejuvenation. Here the authors discuss neuromodulators and fillers in detail, focusing on indications for use, techniques, and common side effects.

The demand for aesthetic augmentation with soft tissue fillers has greatly increased in recent years and has led to an expansion in the number of products available. Unfortunately, an increase in adverse events has followed. These can be categorized into early, late, and delayed. Early infectious complications generally present as a localized skin infection, cellulitis, or abscess. Fillers can also serve as a focus for chronic infection, which is associated with the development of foreign body granulomas, a late complication. Bacterial colonization and indolent infections of the filler site can lead to biofilms that are extremely difficult to treat. Therefore, it is important to focus on prevention through eliciting a thorough patient history including an injection history, practicing sterile technique, and minimizing tissue trauma. Looking forward, much can be done to curtail complication rates. Early teaching and training, a central recording registry for complications, and a standardized filler passport for patients are suggested.

Practical Applications Summary In Private Equity Investment and Local Employment Growth: A County-Level Analysis, from the Winter 2020 issue of The Journal of Alternative Investments, Joshua Cox (of Control Risks) and Bronwyn Bailey (of BB-Advisors) use a new approach to answer the question of whether private equity investment increases employment. Previous studies have been inconclusive or contradictory. Sometimes past results indicated a loss of employment due to increased efficiencies from private equity investment, while other results indicated an increase in employment, albeit a statistically insignificant one. These studies focused on company-level employment growth, however. In contrast, Cox and Bailey examine countywide data and look for spillover effects: employment growth beyond that in the company receiving the private equity investment. The authors examine a host of control variables that might otherwise explain employment growth. In each statistical test, the association between lagged, countywide employment growth and private equity investment is positive and statistically significant. TOPICS:Private equity, global, performance measurement

Identification and treatment of vascular malformations is a challenging endeavor for physicians, especially given the great concern and anxiety created for patients and their families. The goal of this article is to provide a review of vascular malformations, organized by subtype, including capillary, venous, lymphatic and arteriovenous malformations. Only by developing a clear understanding of the clinical aspects, diagnostic tools, imaging modalities, and options for intervention will appropriate care be provided and results maximized.

The timely diagnosis and treatment of dermatologic disease in the pediatric population can be challenging. A basic, yet comprehensive knowledge of common lesions is essential for a successful practice in plastic surgery. In this article, the authors describe vascular, cystic, and pigmented cutaneous lesions that are commonly encountered in the pediatric population. Epidemiology, pathogenesis, clinical course, and management options are discussed for each.

Postoperative scar appearance is often a significant concern among patients, with many seeking advice from their surgeons regarding scar minimization. Numerous products are available that claim to decrease postoperative scar formation and improve wound healing. These products attempt to create an ideal environment for wound healing by targeting the three phases of wound healing: inflammation, proliferation, and remodeling. With that said, preoperative interventions, such as lifestyle modifications and optimization of medical comorbidities, and intraoperative interventions, such as adherence to meticulous operative techniques, are equally important for ideal scarring. In this article, the authors review the available options in postoperative scar management, addressing the benefits of multimodal perioperative intervention. Although numerous treatments exist, no single modality has been proven superior over others. Therefore, each patient should receive a personalized treatment regimen to optimize scar management.

Alloplastic facial implants have a wide range of uses to achieve the appropriate facial contour. A variety of materials such as metals, polymers, ceramics and synthetic injectable fillers are available to the reconstructive and aesthetic surgeon. Besides choosing the right surgical technique and the adequate material, the surgeon must be prepared to treat complications. Infection is an uncommon but serious complication that can cause displeasing consequences for the patient. There are few references in literature regarding treatment and management of facial implant-related infections. This study aims to discuss the role of biofilm in predisposing alloplastic materials to infection, to provide a review of literature, to describe our own institutional experience, and to define a patient care pathway for facial implant-associated infection.

Sea spray aerosol (SSA) is a globally important source of particulate matter. A mesocosm study was performed to determine the relative enrichment of saccharides and inorganic ions in nascent fine (PM2.5) and coarse (PM10-2.5) SSA and the sea surface microlayer (SSML) relative to bulk seawater. Saccharides comprise a significant fraction of organic matter in fine and coarse SSA (11 and 27%, respectively). Relative to sodium, individual saccharides were enriched 14-1314-fold in fine SSA, 3-138-fold in coarse SSA, but only up to 1.0-16.2-fold in SSML. Enrichments in SSML were attributed to rising bubbles that scavenge surface-active species from seawater, while further enrichment in fine SSA likely derives from bubble films. Mean enrichment factors for major ions demonstrated significant enrichment in fine SSA for potassium (1.3), magnesium (1.4), and calcium (1.7), likely because of their interactions with organic matter. Consequently, fine SSA develops a salt profile significantly different from that of seawater. Maximal enrichments of saccharides and ions coincided with the second of two phytoplankton blooms, signifying the influence of ocean biology on selective mass transfer across the ocean-air interface.

Advances in anatomic understanding are frequently the basis upon which surgical techniques are advanced and refined. Recent anatomic studies of the superficial tissues of the face have led to an increased understanding of the compartmentalized nature of the subcutaneous fat. This report provides a review of the locations and characteristics of the facial fat compartments and provides examples of how this knowledge can be used clinically, specifically with regard to soft tissue fillers.

© 2015 American Chemical Society. With the oceans covering 71% of the Earth, sea spray aerosol (SSA) particles profoundly impact climate through their ability to scatter solar radiation and serve as seeds for cloud formation. The climate properties can change when sea salt particles become mixed with insoluble organic material formed in ocean regions with phytoplankton blooms. Currently, the extent to which SSA chemical composition and climate properties are altered by biological processes in the ocean is uncertain. To better understand the factors controlling SSA composition, we carried out a mesocosm study in an isolated ocean-atmosphere facility containing 3,400 gallons of natural seawater. Over the course of the study, two successive phytoplankton blooms resulted in SSA with vastly different composition and properties. During the first bloom, aliphatic-rich organics were enhanced in submicron SSA and tracked the abundance of phytoplankton as indicated by chlorophyll-a concentrations. In contrast, the second bloom showed no enhancement of organic species in submicron particles. A concurrent increase in ice nucleating SSA particles was also observed only during the first bloom. Analysis of the temporal variability in the concentration of aliphatic-rich organic species, using a kinetic model, suggests that the observed enhancement in SSA organic content is set by a delicate balance between the rate of phytoplankton primary production of labile lipids and enzymatic induced degradation. This study establishes a mechanistic framework indicating that biological processes in the ocean and SSA chemical composition are coupled not simply by ocean chlorophyll-a concentrations, but are modulated by microbial degradation processes. This work provides unique insight into the biological, chemical, and physical processes that control SSA chemical composition, that when properly accounted for may explain the observed differences in SSA composition between field studies.

This article reviews the use of modafinil in palliative care, and its use in promoting vigilance and wakefulness. Modafinil’s therapeutic and chemical class, mechanism of action, pharmacokinetics, indications, dosage, side effects, and drug interactions are also discussed. Modafinil seems to fit the requirements of portmanteau, using one drug to treat multiple symptoms.

www.jpedhc.org to subsequent risk of melanoma and other skin cancers (Kennedy, Bajdik, Willemze, De Gruijl, & Bouwes Bavinck, 2003). This finding is significant because the number of children who experience sunburns is staggering. One study demonstrated that 83% of children become sunburned during the summer, and approximately 36% of adolescents have repeated sunburns during the summer (Geller et al., 2002). Subsequent statistics regarding ultraviolet (UV)-related skin cancer are even more troubling. Within the United States, more than 1.3 million new cases of squamous cell and basal cell cancer occur every year, and more than 90% of these cases are caused by overexposure to UV radiation (American Cancer Society, 2009; Jemal et al., 2009). In 2009, the American Cancer Society reported that skin cancer was the most common form of cancer in the United States and that the incidence of new cases of skin cancer per year is greater than the combined incidence of breast, prostate, lung, and colon cancer. This morbidity has resulted in substantial health care costs, as statistics from 2004 have shown that direct costs for treating non-melanomatous skin cancer were estimated to be greater than $1 billion, and greater than $2 billion when indirect costs were included (Bickers et al., 2006). In an effort to prevent these adverse events from occurring, sunscreens have been used as a form of photoprotection. While studies have demonstrated the increased usage of sunscreens for sun protection (Robinson, Rigel, & Amonette, 1997), choosing the proper sunscreen can be a very complicated issue. Early attempts to categorize sunscreens simply based on sun protection factor (SPF) have proven to be inadequate because other factors also play clinically significant roles in the overall effectiveness of sunscreens. The purpose of this report is to examine the current status of sunscreen protection and provide clinically relevant information that health care providers can offer to their patients.

The American Pain Society estimates that 50 million Americans are partially or totally disabled by pain. This striking statistic is certain to increase as our population continues to age. In order to combat this growing problem, healthcare professionals must arm themselves with information. By developing the appropriate pain assessment skills and by staying abreast of the rapidly-changing therapies used in pain management, clinicians can dramatically impact the quality of life of those living with pain.

The case report by Kharlamb and Kourlas[1][1] described a 45-year-old woman suffering from what was presumed to be failed back syndrome associated with lower extremity radiculopathy. The patient’s medical history included depression, anxiety, and possible bipolar disorder. The patient was