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Current submesoscale restratification parameterizations, which help set mixed layer depth in global climate models, depend on a simplistic scaling of frontal width shown to be unreliable in several circumstances. Observations and theory indicate that frontogenesis is common, but stable frontal widths arise in the presence of turbulence and instabilities that participate in keeping fronts at the scale observed, the arrested scale. Here we propose a new scaling law for arrested frontal width as a function of turbulent fluxes via the turbulent thermal wind (TTW) balance. A variety of large-eddy simulations (LES) of strain-induced fronts and TTW-induced filaments are used to evaluate this scaling. Frontal width given by boundary layer parameters drawn from observations in the General Ocean Turbulence Model (GOTM) are found qualitatively consistent with the observed range in regions of active submesoscales. The new arrested front scaling is used to modify the mixed layer eddy restratification parameterization commonly used in coarse-resolution climate models. Results in CESM-POP2 reveal the climate model’s sensitivity to the parameterization update and changes in model biases. A comprehensive multimodel study is in planning for further testing. Significance Statement The ocean surface plays a major role in the climate system, primarily through exchange in properties, such as in heat and carbon, between the ocean and atmosphere. Accurate model representation of ocean surface processes is crucial for climate simulations, yet they tend to be too small, fast, or complex to be resolved. Significant efforts lie in approximating these small-scale processes using reduced expressions that are solved by the model. This study presents an improved representation of the ocean surface in climate models by capturing some of the synergy that has been missing between the processes that define it. Results encourage further testing across a wider range of models to comprehensively evaluate the effects of this adjustment in climate simulations.

This work evaluates the fidelity of various upper ocean turbulence parameterizations subject to realistic monsoon forcing and presents a finite-time ensemble vector (EV) method to better manage the design and numerical principles of these parameterizations. The EV method emphasizes the dynamics of a turbulence closure multi-model ensemble and is applied to evaluate ten different ocean surface boundary layer (OSBL) parameterizations within a single column (SC) model against two boundary layer large eddy simulations (LES). Both LES include realistic surface forcing, but one includes wind-driven shear turbulence only, while the other includes additional Stokes forcing through the wave-average equations that generates Langmuir turbulence. The finite-time EV framework focuses on what constitutes the local behavior of the mixed layer dynamical system and isolates the forcing and ocean state conditions where turbulence parameterizations most disagree. Identifying disagreement provides the potential to evaluate SC models comparatively against the LES. Observations collected during the 2018 Monsoon onset in the Bay of Bengal provide a case study to evaluate models under realistic and variable forcing conditions. The case study results highlight two regimes where models disagree a) during wind-driven deepening of the mixed layer and b) under strong diurnal forcing.

Diurnal Warm Layers (DWLs) play an important role in coupling the atmosphere and the ocean, but their observations in the freshwater dominated Northern Indian Ocean in summer Monsoons are rare. This study focuses on the following aspects of DWLs observed during a 5-day suppressed atmospheric convection phase of the southwest monsoon season in 2019: (i) DWL observations using innovative drifting flux profilers to simultaneously measure high resolution shear and stratification as well as the surface meteorological forcing variables to compute air-sea fluxes (ii) Observed spatial gradients of SST over 1-100 km scales and (iii) Modeling using the popular one-dimensional models increasing in complexity. These observations show regions of marginal shear instability at the DWL base in agreement with previous studies in the tropical Pacific. The commonly used constant stratification assumption within the DWL (e.g. Fairall et al. 1996) breaks down in scenarios with weaker winds and salinity-driven stratification. The vertical structure of DWLs is therefore explored using k-e turbulence closure scheme in General Ocean Turbulence Model (GOTM) framework. Insights from model-observation comparisons show that for days with similar wind speeds, the DWL response can vary based on whether warm water or freshwater advection plays a role. Notably, warm water advection leads to deeper DWLs, whereas the freshwater advection traps the DWL to shallower depths. Further, spatial differences of O(1 C) in diurnal cycles of SST are observed over O (1-100 km), showing remarkable lateral inhomogeneity in the evolution of DWLs.

The capacity of arthropod populations to adapt to long-term climatic warming is uncertain. Here, we combine theory and extensive data on diverse arthropod taxa to show that their rate of thermal adaptation to climatic warming will be constrained in two fundamental ways. First, the rate of thermal adaptation is predicted to be limited by the rate of shift in the temperature of peak performance of four life-history traits in a specific order: juvenile development, adult fecundity, juvenile mortality, and adult mortality. Second, thermal adaptation will be constrained due to differences in the temperature of peak performance among these four traits, which are expected to persist because of trade-offs. By compiling a new global dataset of 61 diverse arthropod species, we find strong evidence that contemporary populations have indeed evolved under these constraints. Our results provide a basis for using relatively feasible trait measurements to predict the adaptive capacity of diverse arthropod populations to climatic warming.

Vector-borne diseases cause significant financial and human loss, with billions of dollars spent on control. Arthropod vectors experience a complex suite of environmental factors that affect fitness, population growth, and species interactions across multiple spatial and temporal scales. Temperature and water availability are two of the most important abiotic variables influencing their distributions and abundances. While extensive research on temperature exists, the influence of humidity on vector and pathogen parameters affecting disease dynamics are less understood. Humidity is often underemphasized, and when considered, is often treated as independent of temperature even though desiccation likely contributes to declines in trait performance at warmer temperatures. This Perspectives explores how humidity shapes the thermal performance of mosquito-borne pathogen transmission. We summarize what is known about its effects and propose a conceptual model for how temperature and humidity interact to shape the range of temperatures across which mosquitoes persist and achieve high transmission potential. We discuss how failing to account for these interactions hinders efforts to forecast transmission dynamics and respond to epidemics of mosquito-borne infections. We outline future research areas that will ground the effects of humidity on the thermal biology of pathogen transmission in a theoretical and empirical framework to improve spatial and temporal prediction of vector-borne pathogen transmission.

Empirically generated indices are used to evaluate the skill of a global climate model in representing the monsoon intraseasonal oscillation (MISO). This work adapts the method of Suhas et al., an extended empirical orthogonal function (EEOF) analysis of daily rainfall data with the first orthogonal function indicating MISO strength and phase. This method is applied to observed rainfall and Community Earth System Model (CESM1.2) simulation results. Variants of the CESM1.2 including upper ocean parameterizations for Langmuir turbulence and submesoscale mixed layer eddy restratification are used together with the EEOF analysis to explore sensitivity of the MISO to global upper ocean process representations. The skill with which the model variants recreate the MISO strength and persistence is evaluated versus the observed MISO. While all model versions reproduce the northward rainfall propagation traditionally associated with the MISO, a version including both Langmuir turbulence and submesoscale restratification parameterizations provides the most accurate simulations of the time scale of MISO events.

Mesoscale eddies are a dominant source of spatial variability in the surface ocean and play a major role in the biological marine carbon cycle. Satellite altimetry is often used to locate and track eddies, but this approach is rarely validated against in situ observations. Here we compare measurements of a small (under 25 km radius) mode water anticyclonic eddy over the Procupine Abyssal Plain using CTD and ADCP measurements from 3 ships, 2 gliders, 2 profiling floats, and one Lagrangian float with those derived from sea level anomaly. In situ estimates of the eddy center were estimated from maps of the thickness of its central isopycnal layer, from ADCP velocities at a reference layer, and from the trajectory of the Lagrangian float. These were compared to three methods using altimetric SLA: one based on maximizing geostrophic rotation, one based on a constant SLA contour, and one which maximizes geostrophic velocity speed along the eddy boundary. All algorithms were used to select CTD profiles that were within the eddy. The in-situ metrics agreed to 97\%. The altimetry metrics showed only a small loss of accuracy, giving $>90$\% agreement with the in situ results. This suggests that current satellite altimetry is adequate for understanding the spatial representation of even relatively small mesoscale eddies.

A coordinated multiplatform campaign collected detailed measurements of a restratifying surface intensified upwelling front within the California Current System. A companion paper outlined the evolution of the front, revealing the importance of lateral advection at tilting isopycnals and increasing stratification in the surface boundary layer with a buoyancy flux equivalent to 2000 W m−2. Here, observations were compared with idealized models to explore the dynamics contributing to the stratification. A 2D model combined with a reduced form of the horizontal momentum equations highlight the importance of transient Ekman dynamics, turbulence, and thermal wind imbalance at modulating shear in the boundary layer. Specifically, unsteady frictional adjustment to the rapid decrease in wind stress created vertically sheared currents that advected horizontal gradients to increase vertical stratification on superinertial time scales. The magnitude of stratification depended on the strength of the horizontal buoyancy gradient. This enhanced stratification due to horizontal advection inhibited nighttime mixing that would have otherwise eroded stratification from the diurnal warm layer. This underscores the importance of near-surface lateral restratification for the upper ocean buoyancy budget on diel time scales.

A coordinated survey between a subsurface Lagrangian float and a ship-towed Triaxus profiler obtained detailed measurements of a restratifying surface intensified front (above 30 m) within the California Current System. The survey began as downfront winds incited mixing in the boundary layer. As winds relaxed and mixing subsided, the system entered a different dynamical regime as the front developed an overturning circulation with large vertical velocities that tilted isopycnals and stratified the upper ocean within a day. The horizontal buoyancy gradient was 1.5 × 10−6 s−2 and associated with vorticity, divergence, and strain that approached the Coriolis frequency. Estimates of vertical velocity from the Lagrangian float reached 1.2 × 10−3 m s−1. These horizontal gradients and vertical velocities were consistent with submesoscale dynamics that are distinct from the classic quasigeostrophic framework used to describe larger-scale flows. Vertical and horizontal gradients of velocity and buoyancy in the vicinity of the float revealed that sheared currents differentially advected the horizontal buoyancy gradient to increase vertical stratification. This was supported by analyses of temperature and salinity gradients that composed the horizontal and vertical stratification. Potential vorticity was conserved during restratification at 16 m, consistent with adiabatic processes. Conversely, potential vorticity near the surface (8 m) increased, highlighting the role of friction in modulating near-surface stratification. The observed increase in stratification due to these submesoscale processes was equivalent to a heat flux of 2000 W m−2, which is an order-of-magnitude larger than the average observed surface heat flux of 100 W m−2.

Background Input from end-users during preclinical phases can support market fit for new HIV prevention technologies. With several long-acting pre-exposure prophylaxis (PrEP) implants in development, we aimed to understand young women’s preferences for PrEP implants to inform optimal design. Methods We developed a discrete choice experiment and surveyed 800 young women in Harare, Zimbabwe and Tshwane, South Africa between September–November 2020. Women aged 18–30 years who were nulliparous, postpartum, or exchanged sex for money, goods or shelter in prior year were eligible; quotas were set for each subgroup. The DCE asked participants to choose between two hypothetical implants for HIV prevention in a series of nine questions. Implants were described by: size, number of rods and insertion sites, duration (6-months, 1-year, 2-years), flexibility, and biodegradability. Random-parameters logit models estimated preference weights. Results Median age was 24 years (interquartile range 21–27). By design, 36% had used contraceptive implants. Duration of protection was most important feature, with strong preference for a 2-year over 6-month implant. In Zimbabwe, the number of rods/insertion sites was second most important and half as important as duration. Nonetheless, to achieve an implant lasting 2-years, 74% were estimated to accept two rods, one in each arm. In South Africa, preference was for longer, flexible implants that required removal, although each of these attributes were one-third as important as duration. On average, biodegradability and size did not influence Zimbabwean women’s choices. Contraceptive implant experience and parity did not influence relative importance of attributes. Conclusions While duration of protection was a prominent attribute shaping women’s choices for PrEP implants, other characteristics related to discreetness were relevant. Optimizing for longest dosing while also ensuring minimal detection of implant placement seemed most attractive to potential users.

Background Islatravir (4′-ethynyl-2-fluoro-2′-deoxyadenosine; EFdA) is a first-in-class nucleoside reverse transcriptase translocation inhibitor (NRTTI) being investigated for HIV treatment and prevention. EFdA is intracellularly phosphorylated to EFdA-triphosphate (EFdA-tp), a competitive substrate of deoxyadenosine-triphosphate (dATP). Thus, translating safety and efficacy findings from preclinical studies relies on the assumption that EFdA’s intracellular pharmacology can be extrapolated across species. Objectives We investigated how EFdA is phosphorylated across animal species commonly used for preclinical models in drug development to identify those that most closely matched humans. Methods PBMCs were isolated from whole blood of six species (human, rhesus macaque non-human primate (rmNHP), rat, minipig, dog, and rabbit) using Ficoll separation and counted on a haemocytometer by Trypan blue staining. One million live cells were cultured in media supplemented with 10 U/mL human IL-2, 10% FBS and 1% antibiotics and treated with 0, 17, 170, and 1700 nM EFdA (n = 3 replicates per concentration). After 24 h, representative cell counts were derived from untreated control wells (as above), cells were washed in PBS, and lysed with 70:30 methanol:water. EFdA-tp and dATP concentrations were quantified by HPLC-MS/MS and normalized to the representative live cell counts for each species. Results When compared to human values, EFdA-tp concentrations for each EFdA treatment concentration were lower in all species (rmNHP 1.5–2.1-fold, rat 4.5–15-fold, minipig 37–71-fold, dog and rabbit >100-fold). Additionally, rmNHP and dog PBMCs exhibited significantly higher (7–10-fold; P < 0.001) dATP when compared with human PBMCs. Conclusions Given intracellular pharmacology differences, these preclinical models may be a conservative estimate of EFdA’s intracellular pharmacokinetics and efficacy in humans.

This paper outlines changes to the ocular surface caused by contact lenses and their degree of clinical significance. Substantial research and development to improve oxygen permeability of rigid and soft contact lenses has meant that in many countries the issues caused by hypoxia to the ocular surface have largely been negated. The ability of contact lenses to change the axial growth characteristics of the globe is being utilised to help reduce the myopia pandemic and several studies and meta-analyses have shown that wearing orthokeratology lenses or soft multifocal contact lenses can reduce axial length growth (and hence myopia).However, effects on blinking, ptosis, the function of Meibomian glands, fluorescein and lissamine green staining of the conjunctiva and cornea, production of lid-parallel conjunctival folds and lid wiper epitheliopathy have received less research attention. Contact lens wear produces a subclinical inflammatory response manifested by increases in the number of dendritiform cells in the conjunctiva, cornea and limbus. Papillary conjunctivitis is also a complication of all types of contact lenses. Changes to wear schedule (daily disposable from overnight wear) or lens materials (hydrogel from SiHy) can reduce papillary conjunctivitis, but the effect of such changes on dendritic cell migration needs further study. These changes may be associated with decreased comfort but confirmatory studies are needed. Contact lenses can affect the sensitivity of the ocular surface to mechanical stimulation, but whether these changes affect comfort requires further investigation.In conclusion, there have been changes to lens materials, design and wear schedules over the past 20+ years that have improved their safety and seen the development of lenses that can reduce the myopia development. However, several changes to the ocular surface still occur and warrant further research effort in order to optimise the lens wearing experience.

STUDY DESIGN: A descriptive psychometric study of precision and concurrent validity of the Thumb Disability Examination (TDX). INTRODUCTION: Thumb carpometacarpal osteoarthritis (CMC OA) is a painful joint condition impacting the functionality of the hand. Therapists use patient-reported outcome measures to evaluate change in disability and symptomology in response to interventions. The TDX is the only condition-specific outcome measure for persons with thumb CMC OA. Its responsiveness, test-retest reliability and concurrent validity with the DASH are published, yet it’s precision and concurrent validity with a hand-region-specific tool has not yet been established. PURPOSE OF THE STUDY: We aimed to determine the precision and concurrent validity of the TDX with a region-specific outcome measure in people with thumb CMC OA. METHODS: Sixteen individuals with a medical diagnosis of CMC OA or a positive pressure-shear test completed the TDX across two visits and the Brief Michigan Hand Questionnaire (bMHQ) at the initial visit. The second visit was 7 to 21 days after the first. Self-administration of the TDX and bMHQ were observed by a licensed occupational therapist. RESULTS: Across total and subscale scores of the TDX, standard error of measurement (SEM) values are used to indicate the precision of tool and demonstrate how confident a user can be that change in score exceeds the error inherent to the tool. Minimal detectable change percentage (MDC%) values for the TDX are acceptable (

Orthokeratology (ortho-k) is the process of deliberately reshaping the anterior cornea by utilising specialty contact lenses to temporarily and reversibly reduce refractive error after lens removal. Modern ortho-k utilises reverse geometry lens designs, made with highly oxygen permeable rigid materials, worn overnight to reshape the anterior cornea and provide temporary correction of refractive error. More recently, ortho-k has been extensively used to slow the progression of myopia in children. This report reviews the practice of ortho-k, including its history, mechanisms of refractive and ocular changes, current use in the correction of myopia, astigmatism, hyperopia, and presbyopia, and standard of care. Suitable candidates for ortho-k are described, along with the fitting process, factors impacting success, and the potential options for using newer lens designs. Ocular changes associated with ortho-k, such as alterations in corneal thickness, development of microcysts, pigmented arcs, and fibrillary lines are reviewed. The safety of ortho-k is extensively reviewed, along with an overview of non-compliant behaviours and appropriate disinfection regimens. Finally, the role of ortho-k in myopia management for children is discussed in terms of efficacy, safety, and potential mechanisms of myopia control, including the impact of factors such as initial fitting age, baseline refractive error, the role of peripheral defocus, higher order aberrations, pupil size, and treatment zone size.

Purpose To assess perceived comfort and related experiences of adapted keratoconic scleral contact lens (17-18.2 mm) wearers with a history of wearing other contact lens modalities and to compare these subjective clinical effects with previous experiences. Methods Twenty-four keratocones were recruited, signed an informed consent approved by the University Internal Review Board, and were asked to complete a survey and a dry eye questionnaire. Results Previous lens wearing experience included soft, piggy back, and hybrid lenses but predominantly was corneal gas permeable. An overwhelming majority strongly preferred the comfort and vision with the scleral contact lenses. This cohort of keratoconus patients were on average dry eye suspects according to a dry eye questionnaire but contained individuals with either normal or significantly dry eye scores. However, patients stated that they experienced less dryness with their scleral lenses, but slightly more than half of these patients experienced, at least occasionally, midday fogging. Conclusions The scleral contact lenses are extremely well accepted by keratoconic patients because of comfort and vision these devices provide. For many patients, they offer further relief from dryness symptoms. However, midday fogging remains a limitation for many wearers.

Submesoscale frontal dynamics are thought to be of leading-order importance for stratifying the upper ocean by slumping horizontal density gradients to produce vertical stratification. Presented here is an investigation of submesoscale instabilities in the mixed layer—mixed layer eddies (MLEs)—as a potential mechanism of frontal slumping that stratifies the upper ocean during the transition from winter to spring, when wintertime forcings weaken but prior to the onset of net solar warming. Observations from the global Argo float program are compared to predictions from a one-dimensional mixed layer model to assess where in the world’s oceans lateral processes influence mixed layer evolution. The model underestimates spring stratification for ~75% ± 25% of the world’s oceans. Relationships between vertical and horizontal temperature and salinity gradients are used to suggest that in 30% ± 20% of the oceans this excess stratification can be attributed to the slumping of horizontal density fronts. Finally, 60% ± 10% of the frontal enhanced stratification is consistent with MLE theory, suggesting that MLEs may be responsible for enhanced stratification in 25% ± 15% of the world’s oceans. Enhanced stratification from frontal tilting occurs in regions of strong horizontal density gradients (e.g., midlatitude subtropical gyres), with a small fraction occurring in regions of deep mixed layers (e.g., high latitudes). Stratification driven by MLEs appears to constrain the coexistence of sharp lateral gradients and deep wintertime mixed layers, limiting mixed layer depths in regions of large lateral density gradients, with an estimated wintertime restratification flux of order 100 W m−2.

The intensive care unit (IGU) is a busy, high stress, complex environment in which health care professionals routinely provide numerous forms of advanced life support and life sustaining measures to a wide mix of critically ill patients. Frontline ICU professionals directly involved in patient care may be subjected to considerable psychosocial stressors and be susceptible to moral distress and burnout.To describe and compare the prevalence and contributing factors to moral distress and burnout among ICUprofessionals in a large quaternary cardiovascular surgery ICU (CVICU).Web-based survey of ICU professionals (registered nurses [RN]/nurse practitioners [NP]; registered respiratory therapists [RRT]; allied health [AH] and physicians [MD]) working in a 24-bed CVICU at the Mazankowski Alberta Heart Institute, between June 15-29, 2015. The survey captured sociodemographic data and integrated the Moral Distress Scale-Revised, the Maslach Burnout Inventory', and a validated job satisfaction questionnaire.One hundred sixty-nine providers completed the sur- vey (response rate 88%). The majority of respondents were aged 26-34 years old (45%), female (79%), married or common law (50%), full-time employed (78%) and had been working in the CVICU for5 years (46%). Moral distress scores were highest among RN/NP (med [IQR] 80 [57-110]) and RRT (85 [61-104]) compared to AH (54 [39-66]) and physicians (66 [43-82], p=0.05). The highest-ranked sources of moral distress were related to controversies on end-of-life care ("Continue to participate in the care for a hopelessly ill person who is being sustained on a ventilator, when no one will make a decision to withdrawal support") and poor communication ("witness healthcare providers giving false hope' to a patient or family"). High, moderate and low levels of burnout syndrome were found in 64.0%, 22.7% and 13.3% of respondents with significantly greater levels among non-physician professionals (p0.001). Job satisfaction was highest for physicians compared with other professionals (p0.001). The item "the recognition you get for good work" was consistently rated as poor across all groups. Moral distress and burnout scores were positively correlated (p0. 001), whereas both were neg- atively correlated with job satisfaction (p0.001 for both). This was primarily driven by RN/NP scores.Moral distress and burnout are common in health- care professionals in a large academic cardiovascular surgery ICU, in particular among nurses and respiratory therapists. Both moral distress and burnout have a negative perception on job satisfaction. These findings will direct strategies to mitigate moral distress and burnout along with enhancing patient care and improving the workplace environment.

Cycling of dissolved organic carbon (DOC) was investigated in anoxic sediments of the Santa Monica Basin, California Borderland, by analyzing the concentration and isotopic signatures (D 14 C and d 13 C) of pore-water DOC and dissolved inorganic carbon (DIC), and organic compound classes extracted from the bulk sediments. DOC and DIC increased across the sediment–water interface, indicating net efflux of these solutes out of the sediments. Throughout the depth interval examined (0–30 cm), the D 14 C value of DOC (D 14 CDOC) was similar to, or higher than, that of bulk sedimentary particulate organic carbon (POC), indicating degradation of relatively 14 C-rich components of POC. There were prominent peaks in both D 14CDOC and D 14 CDIC in the uppermost 2 cm of the sediment column, indicating degradation and remineralization of 14 C-rich, labile organic matter in the near-surface sediments. However, below these sub-surface maxima, D 14 CDOC and D 14 CDIC decreased with depth by � 200& and � 50&, respectively. Given the diffusive time scales, these decreases were too large to be explained by 14 C loss due to radioactive decay. To help explain these observations, we constructed and implemented a selective degradation model that considers bulk pore-water DOC to be the sum of three kinetically- and isotopically-distinct sub-components. Based on this model, the most reactive DOC fraction, which supported � 60% of the DIC production, had a D 14 C value indicating the presence of bomb- 14 C. The intermediate fraction had a D 14 C value of �� 60& and accounted for most of the pore-water DOC standing stock. The least reactive fraction was virtually non-reactive in these sediments, and had a D 14 C value of �� 500&. The benthic DOC flux of this 14 C-depleted, poorly-reactive DOC fraction may represent a source of

The assessment of patient adherence to medication is necessary to distinguish between nonadherence and inferior drug efficacy, which is crucial for avoiding poor clinical outcomes. Adherence measurements pose various challenges, as many methods rely on subjective assessments or slow and costly measurements, which are infeasible in resource-poor settings. Recent developments of new medical devices for delivery of medications requires additional considerations in terms of adherence. In this report, we propose that medical devices may serve a dual-functional purpose: deliver drug and monitor adherence. We provide an illustrative case study that involves assessing the adherence of vaginal rings for delivery of antiretroviral drugs for pre-exposure prophylaxis (PrEP) of HIV.

Organic-rich nearshore sediment was incubated in sealed vessels under sulfate-reducing conditions to investigate the mechanism of dissolved organic carbon (DOC) production in marine sediments. Concentrations and isotopic signatures (δ13C and Δ14C) of particulate organic carbon (POC), DOC, dissolved inorganic carbon (DIC), and particulate inorganic carbon (PIC) were monitored for 130 d. POC solubilization was largely counterbalanced by respiration, resulting in a net increase in DIC of > 35 mmol L−1. Net accumulation of DOC was relatively muted, yet significant, at ∼ 0.04 mmol L−1. All carbon pools exhibited distinct δ13C and Δ14C signatures prior to the incubation. Once the incubation began, these isotopic values varied with time, reflecting exchanges of isotopically distinct moieties across carbon pools. The 14C-enriched (modern) component of bulk POC was selectively solubilized into DOC, and the majority of this DOC was rapidly respired to DIC. However, net accumulation of DOC was accompanied by a drop in Δ14C, suggesting that during selective solubilization of the younger component of bulk POC, there was concomitant solubilization of pre-aged organic matter that subsequently accumulated as DOC. PIC was minor in terms of pool size, but likely played a critical role in determining the δ13C signature of pore-water DIC through isotope exchange.

Fractional abundances of 14C and 13C in dissolved organic carbon (DOC) in sediment porewaters may hold important clues about organic carbon cycling in sediments. Yet there is a dearth of isotopic signatures for porewater DOC because of the difficulty associated with oxidizing DOC in seawater. At present, marine DOC can be processed for analyses of 14C and 13C with high precision and minimal contamination by ultraviolet (UV) oxidation, but this method is resource intensive and could be difficult to implement. To resolve this, a thermal sulfate reduction (TSR) method, previously developed to determine 13C in seawater DOC (Fry et al. 1996), was modified and tested for 14C and 13C determination in porewater DOC. CO2 yields from six test materials ranged between 90% and 108%. δ13C signatures were reproducible within ± 0.4‰ and agreed with independently known values. The 14C and δ13C values of porewater DOC obtained by TSR and UV oxidation showed excellent agreement. Application of TSR to archived porewater DOC samples from a sediment incubation experiment revealed notable changes in isotopic values that were not readily discerned in the DOC concentration data alone. The total uncertainty in the 14C values after blank correction was ± 0.005 to 0.02 fraction modern (Fm) for sample sizes ranging between 143 and 560 µg C. For systems where precision on the order of ± 0.02 Fm is acceptable, TSR could be a viable alternative to UV oxidation for processing small, concentrated marine DOC samples.

A series of poly(cyclohexylethylene-b-ethylene-co-ethylethylene) (C-E/EE) diblock copolymers containing approximately 50% by volume glassy C blocks and varying fraction (x) of EE repeat units, 0.07 ≤ x ≤ 0.90, was synthesized by anionic polymerization and catalytic hydrogenation. The effects of ethyl branch content on the melt state segment–segment (χ) interaction parameter and soft (E/EE) block crystallinity were studied. The percent crystallinity ranged from approximately 30% at x = 0.07 to 0% at about x ≥ 0.30, while the melting temperature changed from 101 °C at x = 0.07 to 44 °C at x = 0.28. Dynamic mechanical spectroscopy was employed to determine the order–disorder transition (ODT) temperatures, from which χ was calculated assuming the mean-field prediction (χNn)ODT = 10.5. Previously published results for the temperature dependent binary interaction parameters for C-E (x = 0.07), C-EE (x = 0.90), and E-EE (x = 0.07 and x = 0.90) fail to account for the quantitative x dependence of χ, based on a simple binary interaction model. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 566–574, 2010

Introduction The modern scleral contact lens (ScCL) has evolved from the very first contact lens fitted 128 years ago. Originally manufactured in glass and oxygen impermeable plastics, these lenses are available today in high Dk gas permeable materials that allow permeation of oxygen, reducing many of the complications that were seen with older generation ScCL. However, as with any new contact lens modality, the modern ScCL brings with it a new set of complications and fitting limitations. Methods Pubmed searches under different keywords were conducted. Results Existing literature provides some reports of infection with the scleral devices, although these are often seen in severely compromised corneas, while hypoxic and inflammatory complications are rarely reported in the literature. Furthermore, the somewhat complex relationship of a scleral lens on the eye can create fitting and removal challenges. Anomalies such as conjunctival prolapse, epithelial bogging, midday fogging, and limbal bearing have been reported, and appear to be unique sequelae to scleral lens wear. Conclusion Although this revolutionary technology broadens the scope in which practitioners can treat patients with irregular ocular surfaces, reports of these complications indicate that there is still a need for continued research to further enhance the clinical outcomes of this promising contact lens modality.

Photon detectors are indispensable in many areas of fundamental physics research, particularly in the emerging field of particle astrophysics, as well as in medical imaging and nuclear non-proliferation. For a significant progress in all these areas a new, inexpensive industrial mass-production photosensor technology is needed. In order to reach that goal we have introduced several innovations. This paper focuses on one of them, the ReFerence flat-panel photon detector. We report on the prototype development, and in particular on the development of a new oxidation-free method for vacuum sealing of glass panel surfaces with liquid indium, at processing temperatures below 360 °C.

[1] During November–December 2009 community rates of gross photosynthesis (Pg), respiration (R) and net calcification (Gnet) were estimated from low-tide slack water measurements of dissolved oxygen, dissolved inorganic carbon and total alkalinity at the historical station DK13 One Tree Island reef, Great Barrier Reef, Australia. Compared to measurements made during the 1960s–1970s at DK13 in the same season,Pg increased from 833 to 914 mmol O2·m−2·d−1 and Pg:R increased from 1.14 to 1.30, indicating that the reef has become more autotrophic. In contrast, Gnet decreased from 133 mmol C·m−2·d−1 to 74 ± 24 mmol C·m−2·d−1. This decrease stems primarily from the threefold increase in nighttime CaCO3 dissolution from −2.5 mmol·m−2·h−1 to −7.5 mmol·m−2·h−1. Comparison of the benthic community survey results from DK13 and its vicinity conducted during this study and in studies from the 1970s, 1980s and 1990s suggest that there have been no significant changes in the live coral coverage during the past 40 years. The reduced Gnet most likely reflects the almost threefold increase in dissolution rates, possibly resulting from increased bioerosion due to changes in the biota (e.g., sea cucumbers, boring organisms) and/or from greater chemical dissolution produced by changing abiotic conditions over the past 40 years associated with climate change, such as increased temperatures and ocean acidification. However, at this stage of research on One Tree Island the effects of these changes are not entirely understood.

Peripartum cardiomyopathy, a type of dilated cardiomyopathy of unknown origin, occurs in previously healthy women in the final month of pregnancy and up to 5 months after delivery. Although the incidence is low—less than 0.1% of pregnancies —morbidity and mortality rates are high at 5% to 32%. The outcome of peripartum cardiomyopathy is also highly variable. For some women, the clinical and echocardiographic status improves and sometimes returns to normal, whereas for others, the disease progresses to severe cardiac failure and even sudden cardiac death. In acute care, treatment may involve the use of intravenous vasodilators, inotropic medications, an intra-aortic balloon pump, ventricular-assist devices, and/or extracorporeal membrane oxygenation. Survivors of peripartum cardiomyopathy often recover from left ventricular dysfunction; however, they may be at risk for recurrence of heart failure and death in subsequent pregnancies. Women with chronic left ventricular dysfunction should be managed according to guidelines of the American College of Cardiology Foundation and the American Heart Association.

Objective: To determine the influence of demographics on patient preferences for community pharmacist attire. Methods: A 10-item questionnaire was developed and administered to patients visiting a chain pharmacy or an independent pharmacy in the Birmingham, Alabama metropolitan area. Mann– Whitney was used to examine if statistical differences existed in chain versus independent pharmacy patient’s selections based on pharmacist attire. Results: A statistically significant difference in patient preference for pharmacist attire between the settings in regards to which pharmacist patients felt was more approachable was observed; 51.2% of chain pharmacy respondents compared to 30% of independent pharmacy respondents identified the pharmacist pair with business formal attire and white coat as more approachable. Differences in education was also apparent with 70% of respondents in the independent pharmacy setting reporting having a Bachelor’s degree or higher compared to 45% of respondents in the chain pharmacy setting. Conclusion: With the exception of approachability, patients indicated preference for pharmacist with the white coat regardless of community setting. Given the importance of patient-pharmacist communication for building successful patientpharmacist relationships, if patients do not perceive the pharmacists as approachable, communication and subsequent development of said relationships may not occur regardless of perceived knowledge and competency.

The authors encountered a renal transplant patient in whom tubular stasis permitted sufficient time to perform SPECT using Tc-99m MAG3. SPECT revealed a defect that was not apparent on the planar study. Renal biopsy showed acute vascular rejection. On a subsequent Tc-99m MAG3 SPECT study the defect had resolved.