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Background: Melanoma disease patterns vary with patient age. Aim: To evaluate sentinel lymph node biopsy (SLNB) in managing melanoma at differing patient ages. Methods: Online prediction tools were applied to compare SLNB positivity (SLNB+) and survival risk at patient ages 20–80. Tübingen melanoma data were used to determine variations in the hazard ratio of SLNB+ for mortality at different patient ages. Results: Regardless of tumour thickness, predicted SLNB+ rates were markedly higher than mortality rates for 20‐year‐old patients. For 80‐year‐old patients, it is the opposite. Discussion: If 1000 20‐year‐olds with a 0.4 mm thickness non‐ulcerated melanoma underwent SLNB, 100 would likely be positive. If all 100 were to be offered adjuvant drug therapy (ADT), fewer than three more melanoma deaths in those 1000 patients would be avoided. In total, 97 patients would have received medication they may never have needed. If 1000 80‐year‐olds with a 3 mm thickness non‐ulcerated melanoma underwent SLNB, only 40 would likely be positive. In total, 274 patients would be predicted to die of melanoma, 245 being SLNB negative and 29 SLNB+. ADT linked to SLNB+ could deny treatment to 89% of these high‐risk patients. Limitations: The authors relied on published risk data. Conclusion: SLNB has poor specificity at predicting mortality in young melanoma patients and poor sensitivity in older patients. SLNB is not indicated in managing cutaneous melanoma for patients under 40 or over 60 years of age. Many such patients could be managed with wide local excision alone in their clinician's office‐based practice. For all cutaneous melanoma patients at all ages, linking ADT to BAUSSS biomarker, (an algorithm of Breslow thickness, age, ulceration, subtype, sex and Site) rather than SLNB+ is likely more appropriate. BAUSSS provides a more accurate melanoma‐specific mortality risk assessment for patients without burdening them with added surgery, hospitalization, costs or morbidity risk. [ABSTRACT FROM AUTHOR]

Background: Maximizing survival for patients with primary cutaneous melanomas (melanomas) depends on an early diagnosis and appropriate management. Several new drugs have been shown to improve survival in high-risk melanoma patients. Despite well-documented guidelines, many patients do not receive optimal management, particularly when considering patient age. Objective: to provide an update on melanoma management from the time of the decision to biopsy a suspicious skin lesion. Methods: We reviewed melanoma-management research published between 2018 and 2023 and identified where such findings impact and update the management of confirmed melanomas. Pubmed, Google Scholar, Ovid and Cochrane Library were used as search tools. Results: We identified 81 publications since 2017 that have changed melanoma management; 11 in 2018, 12 in 2019, 10 in 2020, 12 in 2021, 17 in 2022 and 18 in 2023. Discussion: Delayed or inaccurate diagnosis is more likely to occur when a partial shave or punch biopsy is used to obtain the histopathology. Wherever feasible, a local excision with a narrow margin should be the biopsy method of choice for a suspected melanoma. The Breslow thickness of the melanoma remains the single most important predictor of outcome, followed by patient age and then ulceration. The BAUSSS biomarker, (Breslow thickness, Age, Ulceration, Subtype, Sex and Site) provides a more accurate method of determining mortality risk than older currently employed approaches, including sentinel lymph node biopsy. Patients with metastatic melanomas and/or nodal disease should be considered for adjuvant drug therapy (ADT). Further, high-risk melanoma patients are increasingly considered for ADT, even without disease spread. Invasive melanomas less than 1 mm thick are usually managed with a radial excision margin of 10 mms of normal skin. If the thickness is 1 to 2 mm, select a radial margin of 10 to 20 mm. When the Breslow thickness is over 2 mm, a 20 mm clinical margin is usually undertaken. In situ melanomas are usually managed with a 5 to 10 mm margin or Mohs margin control surgery. Such wide excisions around a given melanoma is the only surgery that can be regarded as therapeutic and required. Patients who have had one melanoma are at increased risk of another melanoma. Ideal ongoing management includes regular lifelong skin checks. Total body photography should be considered if the patient has many naevi, especially when atypical/dysplastic naevi are identified. Targeted approaches to improve occupational or lifestyle exposure to ultraviolet light are important. Management also needs to include the consideration of vitamin D supplementary therapy. [ABSTRACT FROM AUTHOR]

The numbers per tiller (abundance) and per unit area of ground (population density) of the dominant cereal aphids in winter wheat crops, Sitobion avenae (Fabricius) and Metopolophium dirhodum (Walker) (Hemiptera: Aphididae) were recorded from 2000–2015. The results were used to test the hypothesis that at the population peak and 4 weeks previously, the population density of aphids in winter wheat crops (Triticum aestivum L., Poaceae) is uniformly distributed with respect to surface area and, as a result, their abundance is high in sparse stands (SPA) where the colonizing aphids are scattered among a small number of tillers (ca. 80 m−2), and low in dense stands (DEN) where they are scattered among a larger number of tillers (ca. 440 m−2). This prediction was verified for S. avenae, the population density of which did not significantly differ between SPA and DEN stands throughout this period. This species feeds mainly on the ears, whose nutritional quality for aphids varies little with crop density and during the course of ripening. In contrast and contrary to our prediction, the population density of M. dirhodum increased throughout this period more rapidly in SPA than in DEN stands. This species lives on leaves whose quality is better and remain present for longer during the course of ripening of the crop in SPA than DEN stands. The abundance of both species was higher in SPA than in DEN stands. Greater direct damage to cereal crops can be expected when using technologies and cultivars of winter wheat that need to be planted sparsely. [ABSTRACT FROM AUTHOR]

Particle-resolved computational fluid dynamics simulations of flow and pressure drop in fixed beds of spheres give poor accuracy at higher Reynolds number (Re) under turbulent conditions. The influence of meshing is investigated for two cases, a face centered cubic packing with no wall effects, and a narrow bed of tube-to-particle diameter ratio three with strong wall effects. Local approaches to meshing at contact points were compared, using both surface flattening (caps) and bridging between spheres. Accurate results for pressure drop at moderate to high Re > 1000 required computationally expensive fine uniform meshes, however at highest Re pressure drop appeared to be low. The use of boundary adaption improved results with less expensive meshes. The aspect ratio of surface prisms and the sizes of the bridges used at contact points had strong effects. Velocity profiles were much less sensitive to the mesh refinement and could be obtained at reasonable cost. [Display omitted] • Systematic body-fitted mesh development for pressure drop in beds of spheres. • Fine uniform meshes give accurate pressure drop, are impractical for full beds. • Bridges used for contact point treatment should be relatively small. • If prism cells are used on surfaces their aspect ratio should be below five. • Accurate pressure drop computations need finer meshes than velocity profiles. [ABSTRACT FROM AUTHOR]

Direct hydrogen reduction (H-DR) is a promising technology for green ironmaking. Given the absence of commercial H-DR data, computational simulation is a powerful tool for engineering and overcoming the complexity of the system. This study develops a multiscale moving-bed reactor model to simulate non-catalytic gas-solid reactions and evaluate parameters at the pellet scale that hierarchically impact the performance at reactor scale. The reactor and solid particles are treated as coupled physical domains, enabling the computation of the solid transformations along both scales. Predictions for H-DR process highlight the substantial supply of H 2 molar flow in enhancing reactor performance. A sensitivity multivariate analysis revealed the significant effect of pellet structural characteristics and gas inlet conditions on the process. Increased pellet porosity offers flexibility for process optimization, enabling the use of lower H 2 percentages and temperatures. These findings provide valuable insights into optimizing H-DR process, improving energy efficiency, and better H 2 utilization. [Display omitted] • Finite element method to discretize both pellet and reactor. • Multiphysics-multiscale simulation for non-catalytic gas-solid reactions. • Multivariate sensitivity analysis of the Hydrogen Direct Reduction process. • Impact of pellet structure on the reactor performance. • Identification of optimal conditions for green iron production. [ABSTRACT FROM AUTHOR]

• Axial thermowells change the void fraction and cause flow by-passing in fixed beds. • For phthalic anhydride synthesis, thermowells displace hot-spots downstream. • Axial thermowell measurements can underestimate hot-spot temperatures. • Temperature errors do not always decrease with thermowell size, due to local effects. The present study analyses the thermowell system for monitoring temperatures in a fixed bed catalytic reactor for the highly exothermic partial oxidation of o-xylene to phthalic anhydride. Particle-resolved computational fluid dynamics (CFD) simulations are presented for the cases of randomly-packed spheres inside cylindrical tubes with tube-to-particle diameter ratios (N) of 3.96, 5.96 and 7.99. Results are obtained for each N value for cases with inner thermowell radius to outer tube radius ratios of 0.0 (no thermowell), 0.05, 0.1 and 0.2. Comparisons of radial void fraction and axial velocity profiles, axial pressure drop and axial temperature profiles under reaction conditions are presented. The presence of the thermowell did change the mass and heat transfer and reaction inside and around the particles, especially at the bed center. The configurations of catalyst particles were rearranged, leading to changes in voidage, flow and temperature profile. The axial temperature profiles from the thermowells differed from the profiles in the undisturbed beds. [ABSTRACT FROM AUTHOR]

Axial thermowells are used to monitor temperature in lab scale and pilot plant fixed-bed catalytic reactor tubes. Particle-resolved fixed-bed computational fluid dynamics simulations are used to study the local changes in particle location, flow, and temperature that result from using thermowells in narrow packed tubes. The bed structure, velocity, and temperature were compared for randomly packed spheres in heated-wall tubes. Tube-to-particle diameter ratios 3.96, 5.96, and 7.99 were used, each with three different thermowell sizes and with no thermowell. The measured axial temperature profiles differ from those in the un-instrumented beds due to conduction and flow by-passing along the thermowells. [ABSTRACT FROM AUTHOR]

3 Brown, P.M.J. & Roy, H.E. (2017) Native ladybird decline caused by the invasive harlequin ladybird Harmonia axyridis: evidence from a long-term field study. Thus, I decline in percentage abundance does not necessarily indicate a negative effect of the invader on the abundance of the native species i , as is often claimed (Alyokhin & Sewell, 2004; Grez I et al i ., 2016; Brown & Roy, 2017, etc.). It is seductive to say that an invader in reducing the abundance of native predators lowers the biocontrol potential of the whole guild (Soares I et al i ., 2008; Brown I et al i ., 2011; Roy I et al i ., 2012). [Extracted from the article]

The 2001 patients who enrolled in MSLT1 to contribute knowledge for future patients with melanoma deserve full publication of all undisclosed findings. There is a lack of adequate and appropriate reporting of key data from the Multicenter Selective Lymphadenectomy Trial 1 (MSLT1) of melanoma. SP d sp Percentages in the total patient columns are incomplete, missing outcomes for patients with thin melanoma. [Extracted from the article]

Modelling of empirical data on the abundance of host-specific, tree-dwelling aphids indicates that their abundance is determined by the effect of the abundance of their host plants on the realised annual population growth rate ( I R i ) of the aphids (Dixon & Kindlmann, [7]). Viewed in this way it is not just the abundance of the host plant of aphids that determines the abundance of aphids (Dixon & Kindlmann, [7]) but also their potential annual population growth rate ( I r i SB p sb ) and subsequently their realised population growth rate ( I R i ). The most striking and consistent feature of rare aphid species is that the period suitable for their development and reproduction is shorter than for the common species and, consequently, the potential yearly rate of increase of these rare species is lower. [Extracted from the article]

A promising workflow for computational generation and meshing of resolved-particle randomly packed beds of arbitrary-shaped particles is described. The workflow is based on an automated package that is developed for the Bullet Physics Library for packed bed generation, and on the shrink-wrap method for handling the meshing challenges of the particle contact areas. Packed bed properties such as radial voidage and particle angle distributions are validated against existing experimental data and theoretical methods in the literature. Furthermore, the accuracy of the generated mesh using the shrink-wrap technique is evaluated by calculating the bulk and radial voidage distribution, the pressure drop, and by velocity profile and heat transfer analysis using computational fluid dynamics (CFD) simulations. It is shown that the proposed workflow can speed up the process of the geometry and mesh generation while it maintains the structural features of the bed. Finally, applications of such geometries to fixed bed reaction engineering problems are presented to illustrate simulations that can be achieved using the new workflow. [ABSTRACT FROM AUTHOR]

The deactivation of catalysts is an important problem in the strongly endothermic steam methane reforming reaction. The local carbon laydown on the catalyst surface may lead to local hot spots, breakage of catalyst particles, and blockage of the reactor tube. Local carbon formation was studied at different operating conditions using particle-scale 3D CFD models of full and hollow cylindrical particles. The results showed that a low steam-to-carbon ratio may cause local carbon formation at high temperature (\gt900K) on the surface of the catalyst particle. The risk of carbon formation was highest at the surface hot spots and inside the catalyst particles where the methane cracking reaction rate exceeded those of the gasification reactions. The internal surface in the 1-hole catalyst particle showed favorable conditions for carbon formation and deposition, similarly to the external surface of the particle. 3D CFD simulations of a 0.76 m length of a full tube of spherical catalyst particles with tube-to-particle diameter ratio 5.96 showed that the rate of carbon formation was much higher next to the heated tube wall and decreased significantly from the tube wall to the tube center. [ABSTRACT FROM AUTHOR]

Resolved-particle 3-D computational fluid dynamics (CFD) simulations are presented of endothermic steam methane reforming in a random packed bed of 807 spherical catalyst particles at a tube-to-particle diameter ratio of N = 5.96 with constant wall heat flux. The fluid flow field is fully coupled to the temperature and species distributions inside the particles. This enables simulation of diffusion, conduction and reaction inside the catalyst particles, as opposed to only surface reactions. The results illustrate 3-D distributions of flow, temperature, species and reaction rates inside a 0.7 m length of packed tube. These show large variations on near-wall particle external surfaces, and non-symmetric distributions inside the catalyst particles on cross-sections through the bed. The detailed CFD approach allows statistical analysis of the particle-to-particle reaction rate variations, the correlation of rate with location in the bed, and the intrinsic variability of radial temperature and species mass fraction profiles. Comparisons to a 1-D reactor tube heterogeneous effective medium model showed that axial profiles of cross-sectional average temperature, species and velocity could not be reproduced using particle-fluid heat and mass transfer coefficients estimated from non-reacting simulations in the same tube. Comparisons to a 2-D reactor tube heterogeneous effective medium model showed good agreement with axial profiles if radial local void fractions and axial velocities were included in the model. Improved agreement with radial temperature profiles resulted from the model with a radially-varying effective radial thermal conductivity. [ABSTRACT FROM AUTHOR]

An implementation of a simplified microkinetics model in three-dimensional computational fluid dynamics (CFD) simulations of an ethylene oxide fixed-bed reactor is proposed. An existing microkinetics model in the literature is simplified to a model with general rate expressions to reduce the complexity of the computations. It then is coupled with CFD simulations of flow in the fixed bed and transport inside the catalyst particles. Illustrative CFD simulations are carried out in a randomly packed bed of 120 spherical particles, which take into account surface species under steady-state conditions in the particles. The proposed approach represents a practical method to integrate simplified surface chemistry with a realistic-scale fixed bed for more in-depth analysis. It is shown that the surface coverages can be greatly affected by the surrounding flow conditions; furthermore, the effects of transport limitations, products, and different inlet compositions on the ethylene oxide selectivity are studied. [ABSTRACT FROM AUTHOR]

A method is developed to couple microkinetics with fluid flow in a fixed bed and transport inside the catalyst particles using computational fluid dynamics. Initially, the microkinetics model is solved for a wide range of different temperatures, and partial pressures. Next, reaction rates are mapped into quadratic multivariate splines. Splines coefficients are then imported into our user-defined function, and consequently the reaction rates are evaluated at each iteration simultaneously with the CFD simulations. This method has been applied to our solid particle model to investigate the effects of fluid flow, transport and elementary reaction steps on each other for ethylene and methanol partial oxidations. Reaction rates of all elementary steps as well as species surfaces sites and compositions are evaluated inside the particle. The suggested method can couple complex reaction mechanisms with detailed CFD simulations without increasing the computational time compared with global kinetics methods. [ABSTRACT FROM AUTHOR]

This work examines how the angle to the flow of a 1-hole catalyst particle impacts its catalytic performance. Computational fluid dynamics (CFD) simulations are reported for flow past a single equilateral hollow cylinder under methane steam reforming conditions, for 1000 ≤ Re ≤ 10,000, and for approach angles from 0° to 90°. The simulations show that at 0°, the flat end of the particle causes separation and formation of a large wake region, while a jet-like flow results through the center hole. These flows result in a pattern of vortices behind the particle, with reverse flow along the particle length. These features are distorted as the approach angle increases, with boundary-layer formation on the upstream side of the particle and a complex vortex pattern on the downstream side. The flow through the particle hole decreases with incidence angle. Surface heat and mass fluxes decrease for the flat ends and the inside curved surface, and increase on the outside curved surface. Both reactant consumption and energy uptake show maxima as a result of the changes in transfer rates through the various particle surfaces, caused by the incident flow. [ABSTRACT FROM AUTHOR]

OBJECTIVES To determine whether field photodynamic therapy (PDT) of actinic keratoses using a novel preparation of 5-aminolevulonic acid (novel ALA) results in fewer subsequent invasive skin cancers developing on the face of individuals with previous facial cutaneous malignancy in a prospective randomized controlled trial. METHODS AND MATERIALS Intervention patients received two treatments of novel ALA 2 weeks apart. Controls were observed. Patients were followed up with biopsy of any suspicious lesions for 3 years. RESULTS The trial was suspended early because of problems with trial governance and the reporting of severe adverse events. Sixty-four patients who were recruited at that time at one center were monitored. Their average age was 71, and 57% were male. Patients were randomized to intervention {n = 34) or observation (n = 29). Over the subsequent 3 years, 13 intervention patients (38%) developed 30 new cutaneous malignancies in the field treated, and 11 control patients (38%) developed 22 new malignancies. Some intervention patients experienced prolonged adverse events, including permanent scarring. CONCLUSION Novel ALA made no difference in the likelihood of new malignancies developing. The risks without benefit of this novel ALA are troubling. Lack of efficacy and safety of novel ALA cannot be extrapolated to other PDT products. [ABSTRACT FROM AUTHOR]

A newvelocity-based approach to fixed bed radial heat transferis presented. Axial and radial velocity components were averaged fromdetailed 3D computational fluid dynamics (CFD) fixed bed simulationsof computer-generated beds of spheres and used to model radial thermalconvection. The convection terms were coupled with a radially varyingstagnant bed thermal conductivity in a 2D pseudocontinuum fixed-bedheat transfer model. The usual effective radial thermal conductivity krand apparent wall heat transfer coefficient hwwere not used, and there were no adjustableparameters. The radial and axial temperature variation predicted bythe velocity-based model agreed well with the angular-averaged temperaturesfrom the detailed 3D CFD simulations over the range 80 ≤ Re≤ 1900 and for N= 3.96, 5.96,and 7.99. [ABSTRACT FROM AUTHOR]

Abstract: For the conduction mode of heat transfer in a fixed bed, we have carried out an evaluation of whether the most widely-used equations for the overall stagnant bed effective thermal conductivity ke 0, the Zehner–Schlünder cell model, can be used on a pointwise basis to obtain local values of ke 0(r) using the local bed voidage, ε(r). A three-dimensional computational fluid dynamics (CFD) model of an annular test bed of spheres with tube-to-particle diameter ratio equal to four was constructed to obtain the local void fraction, and solved for the radial temperature profiles. Comparisons to a one-dimensional pseudo-continuum model with ke 0(r) gave good agreement for a range of values of solid thermal conductivity, establishing that the Zehner–Schlünder cell model can be used in local models of fixed-bed heat transfer. [Copyright &y& Elsevier]

Aphidophagous and coccidophagous ladybirds, similar to their prey, show marked differences in their pace of life (Dixon, 2000), in particular in their rate of development, with all stages of aphidophagous species developing much faster than those of coccidophagous species. Two hypotheses are proposed to account for the large difference in the pace of life of these two groups. These are that differences in the rate of development are a result of differences in lower temperature thresholds for development or the quality of their respective prey as food (Dixon et al., 2011). Analysis of published results on the rates of development of the eggs of ladybirds indicates that the inverse relationships between the number of day-degrees required for development ( K) and the lower temperature threshold for development ( tdmin) of these two groups are significantly different. In particular, the respective tdmin overlap and K of the aphidophagous and coccidophagous species with a similar tdmin are, on average, 38 and 117 day-degrees (Do). The relationship between the rate of development ( R) and temperature ( T) for aphids reared on poor- or high-quality foods indicates that, although the value of tdmin of a species depends on food quality, K does not, showing that it is unlikely that K is governed by food quality. Thus, there is little support for differences in either the tdmin or food quality governing the difference in the pace of life of these two groups of ladybirds. The results indicate that the physiological mechanism that may govern the difference in the pace of life between these two groups is the number of day-degrees ( K) needed to complete their development. The possible evolutionary reason for this is discussed. [ABSTRACT FROM AUTHOR]

Abstract: In the development of meshes for computational fluid dynamics (CFD) simulations of transport in fixed beds of spheres, particle–particle and wall–particle contact points often present difficulties. We give results for drag coefficient (C D ) and heat flow (Q) for flow past sphere–sphere and wall–sphere contact points, focusing on higher flow rates typical of industrial steam reformers (500

Complex interactions between steam methane reforming reaction rates, conduction, and diffusion inside cylindrical catalyst particles with holes, and the external flow and temperature fields near the heated tube wall were shown in detail using computational fluid dynamics and compared to prior work on full cylinders. This work highlights the differences caused by the particle features. Simulations were done under industrial tube inlet conditions at a constant pressure drop for one-, three-, four-, and six-hole cylinders. Heat and mass fluxes were within 10% for all particle surfaces; the holes provided the reactant good access to the particles. The six-hole catalyst particles offered the best temperature distribution and reaction rate. However, the four-hole particles gave a higher mass flow rate and lower tube-wall temperature for a set pressure drop. [ABSTRACT FROM AUTHOR]

In the United States, an objective of coastal states is providing sufficient access to coastal resources. To better utilize public resources for such projects, decision makers would benefit from possessing reliable estimates of economic values coastal residents and tourists place on public beach access. This study’s purpose is to estimate the economic values coastal residents and tourists assign to public beach access, and provide options for financing such projects. Estimates of these values were calculated using the doubled-bounded dichotomous choice contingent valuation technique. Results indicated that coastal residents were willing to pay $2.46 for additional public beach access, while coastal tourists’ mean willingness to pay was $6.33. Findings suggest additional public beach access locations are desirable to both coastal residents and tourists. Supplying coastal resource managers with these values can assist in justifying the use of public resources on beach access projects, as well as in the development of long-term policies. [ABSTRACT FROM PUBLISHER]

Abstract: The highly endothermic commercial methane steam reforming (MSR) reaction was studied experimentally in a single-pellet-string fixed bed reactor. The temperatures inside the active catalyst particles, the temperatures on the outer surfaces of selected pellets and the exit gas composition were measured. The MSR reaction showed strong effects on the temperature profile along the reactor, causing it to decrease initially. A computational fluid dynamics (CFD) model was used to predict temperature and species profiles under the experimental MSR reaction conditions. Comparison of CFD and experimental data showed very good qualitative as well as quantitative agreement for temperature inside catalyst particles at different inlet gas temperatures, and for the temperature drop from outside to inside the pellets due to the reaction heat sink. Trends in methane conversion were also well-represented by the CFD simulation. [Copyright &y& Elsevier]

Abstract: CFD simulations of heat transfer in fixed beds of spheres were validated by comparison to experimental measurements in a pilot-scale rig. The comparisons were made for particle Reynolds numbers in the range 2200

Abstract: To develop and validate meshes for computational fluid dynamics (CFD) simulations of transport in fixed beds, a single particle is often used as a test case. We present results for drag coefficient (C D) and heat transfer Nusselt number (Nu) for flow past a sphere, focusing on high flow rates typical of industrial steam reformers (400< Re <20,000). Over this range, good predictions of C D were obtained using large eddy simulation (LES) to capture vortex shedding and wake dynamics, with a mesh refined downstream from the sphere. The small time-steps and high cell count required make this too expensive for fixed beds. Nu can be accurately calculated using a Reynolds-averaged Navier–Stokes (RANS) method with shear-stress transport (SST) k–ω closure provided the mesh at the particle surface is fine enough and covers most of the boundary layer. Single sphere simulations of heat transfer are more useful for fixed bed mesh development than drag coefficient calculations. [Copyright &y& Elsevier]

Clean, non-contaminated skin surgery is associated with low rates of surgical site infection (SSI), bacterial endocarditis, and joint prosthesis infection. Hence, antibacterial prophylaxis, which may be associated with adverse effects, the emergence ofmultidrug-resistant pathogens, and anaphylaxis, is generally not recommended in dermatologic surgery. Some body sites and surgical reconstructive procedures are associated with higher infection rates, and guidelines for SSI antibacterial prophylaxis have been proposed for these cases. Large prospective, controlled trials are needed to ascertain the role of oral SSI prophylaxis for these surgical sites and procedures especially in patients with diabetes mellitus who are intrinsically at greater risk of SSI. Topical antibacterial ointment and sterile paraffin appear to make no difference to healing or the incidence of SSIs in clean wounds. Although further research is needed, preliminary studies have shown that intraincisional antibacterials, which may be associated with fewer adverse effects and a lower risk of multidrug-resistant bacteria, could potentially be helpful for SSI prophylaxis. Trials using honey- and silver-impregnated dressings have found no advantage in the healing of chronic wounds. However, several case studies, which need corroboration in larger studies, suggest that these dressings may be helpful in preventing and treating SSIs. Bacterial endocarditis and joint prosthesis infection prophylaxis are not routinely recommended in cutaneous surgery. The updated 2007 American Heart Association guidelines now advocate bacterial endocarditis prophylaxis for high-risk cardiac patients having surgery involving the oral mucosa or infected skin. The latest American Dental Association/American Academy of Orthopaedic Surgery guidelines recommend considering antibacterial prophylaxis for oral procedures where bleeding is anticipated and for surgery involving acute orofacial skin infections if the patient has had a total joint replacement within 2 years or is in a high-risk group and has had a joint replacement at any time. [ABSTRACT FROM AUTHOR]

1. Generalist predatory insects that exploit unpredictable and ephemeral prey should allocate metabolic resources differently to soma and gonads than specialist species. As the former have more opportunities to encounter a wide array of prey than specialists, the expectation is that they will more rapidly resorb oocytes when food is scarce. By doing so, they reallocate resources to the soma to support the search for oviposition sites of a better quality. Similarly, they are expected to resume oogenesis faster than the specialist when good conditions return. 2. This hypothesis was tested by comparing a generalist and a specialist ladybird species belonging to the same genus. 3. A resorption index was calculated for females of both species subjected to several starvation regimes. This index indicated that over a period of fasting of 3 days, the intensity of resorption was greater in the generalist than the specialist. When food was again supplied, oogenesis resumed and within 1 day was faster in the generalist than in the specialist. 4. As predicted, the resorption of oocytes and replenishment occurred faster in the generalist than in the specialist species. This is the first time, to our knowledge, that the speed and intensity of the ovarian dynamics of a predatory insect have been linked to its way of life. [ABSTRACT FROM AUTHOR]

OBJECTIVE To study the association between known diabetes and complications after skin surgery. METHOD In a 5-year prospective observational study, 7,224 lesions were excised on 4,197 patients in a referral center involving one surgeon in a southern Australian locale. RESULTS One hundred ninety-six patients with known diabetes (4.7%) underwent 551 excision procedures (7.6%) 4,001 people without diabetes underwent 6,673 procedures. Patients with diabetes were older (72 ± 13) than those without (64 ± 17) ( p<.001.) Infection incidence was significantly higher in patients with diabetes (4.2%, 23/551) than in those without (2.0%, 135/6,673) ( p<.001). There were five bleeds in patients with diabetes (0.9%) versus 47 in those without (0.7%) ( p=.58). The incidence of wound dehiscence in patients with diabetes (2) was not different from that in those without (22), ( p=.90). Noninfective complications were 1.8% for patients both with diabetes (10/551) and those without (118/6,673). Two thousand three hundred seventy-one flaps resulted in 14 (0.6%) cases of end-flap necrosis, but no case occurred in patients with diabetes. Multivariate analysis using binary logistic regression demonstrated that known diabetes was predictive of infection (odds ratio=1.66, 95% confidence interval=1.05–2.65). Diabetes was not predictive of other complications. CONCLUSION Patients with known diabetes suffer more postoperative skin infections than those without. Noninfective complications are similar. Clinicians may consider antibiotic prophylaxis in their patients with diabetes facing high-risk skin surgery. [ABSTRACT FROM AUTHOR]

1. The objective of this study was to test the theoretical prediction that the thermal tolerance range for development in insects should be about 20 °C. 2. The data on the thermal requirements for development of 66 species from eight orders of insects was obtained from the literature. The temperatures at which the developmental rates are at their minimum and maximum was obtained for each population by defining the relationship between developmental rate (1/ D) and temperature, using either Lactin et al.'s (1995 ) or Briére et al.'s (1999 ) model. 3. Thermal windows, i.e. the range in temperature between the minimum and maximum rate of development for individual species, and the relationship between the minimum and maximum temperatures, were examined. 4. The mean thermal window, 19·8 °C with 95% confidence interval 19·1–20·5 and range 13·3−28·6, was influenced by species phylogeny, with the windows narrower for species having a true pupal stage, but not by ecological traits thought to affect species thermal requirements. The relationship between the minimum and maximum temperatures was highly significant and independent of species phylogeny. 5. Theory and this analysis of empirical data indicate that each species of insect can only develop over a limited range of temperatures independent of species traits. In addition, the relationship between the minimum and maximum developmental rates co-vary independent of species phylogeny. This may help identify the precise nature of the physiological mechanism underlying the seasonal development and distribution of insects, and possibly other ectotherms. [ABSTRACT FROM AUTHOR]

The aim of this study is to examine small area variation in crime trajectories during the COVID-19 pandemic in England and Wales. While we know how police-recorded crime responded to lockdown policies at the 'macro' level, less is known about the extent to which these trends were experienced uniformly at localized spatial scales. Longitudinal k-means clustering is used to unpick local area variation in police notifiable offences across England and Wales. We describe the clusters identified in terms of their spatial patterning, opportunity structures and crime type profile. We find that in most small areas, crime remained fairly stable throughout the pandemic. Instead, a small number of meso-level areas contributed a disproportionately large amount to the macro-level trend. These were typically city centers with plentiful pre-pandemic crime opportunities, dominated by theft and shoplifting offences. Findings offer support for opportunity theories of crime and for a mobility theory of crime during the pandemic. We explore potential implications for policy, theory and further research. • Studies showing macro-level crime declines during the coronavirus pandemic have not tended to examine how this occurred at the local area level. • We find that crime in most small areas remained fairly stable but a small number of meso-level areas contributed disproportionately to the macro-level trend. • The small areas that changed most were city centers dominated by theft and shoplifting offences. • The findings support crime opportunity theories and the mobility theory of crime change during the pandemic. [ABSTRACT FROM AUTHOR]

The hypothesis that small species of aphidophagous coccinellids need lower aphid population densities for reproduction than large species (Dixon, 2007) was tested in the field. In 2006 we compared seasonal changes in the oviposition behaviour of two coccinellid species regularly found in cereal stands in central Europe, the large Coccinella septempunctata L. and the small Propylea quatuordecimpunctata (L.). Adults of both species were collected at 2-3 day intervals from stands of winter wheat and spring barley, females were allowed to deposit eggs for 24 h following collection and the percentage that laid eggs and the number of eggs were recorded. Both species colonized the cereal crop simultaneously in the middle of May. After colonization of the crop, while the aphid density was still low, few females of C. septempunctata oviposited and laid only a few eggs. Oviposition increased up to a maximum c. 1 month later and was closely associated with prey abundance. Of the females of P. quatuordecimpunctata, whose mass is about one quarter of that of the former species, the percentage ovipositing and number of eggs laid varied less in time and was less associated with prey abundance than in C. septempunctata. As predicted by theory, the small P. quatuordecimpunctata was more effective at exploiting the lower prey densities as it produced proportionally more of its eggs during the early stages of the aphid infestation than the larger C. septempunctata. [ABSTRACT FROM AUTHOR]

Abstract: Computational fluid dynamics (CFD) was used to simulate non-reacting heat transfer in a steam reforming packed reactor tube of tube-to-particle diameter ratio () equal to 4, with cylindrical multi-hole catalyst particles. These simulations extend those of our previous study [Nijemeisland, M., Dixon, A.G., Stitt, E.H., 2004. Catalyst design by CFD for heat transfer and reaction in steam reforming. Chemical Engineering Science 59, 5185–5191] to provide accurate tube wall temperatures, runs at constant pressure drop in addition to those at constant mass flow rate and simulations of particles with different sizes of holes. At constant pressure drop, particles with higher void fractions allowed higher mass flow rates, resulting in tube wall temperatures and radial temperature profiles in order: solid cylinders one-hole particles multi-hole particles. Little difference was seen between three-hole and four-hole particles. The particles with multiple holes gave a substantial reduction in tube wall temperature, with only a small decrease in core tube heat transfer. The effect of hole size was small, for the cases investigated in this study. [Copyright &y& Elsevier]

To test the predictions of allometric analyses of laboratory data on aphidophagous ladybirds, a study was carried out on a small [ Propylea quatuordecimpunctata (L.); dry female body mass 3.7 mg] and large species ( Coccinella septempunctata L.; 15.4 mg) (both Coleoptera: Coccinellidae) of predatory ladybird, which regularly exploit cereal aphids. In 2003–2006, females of C. septempunctata and in 2006 P. quatuordecimpunctata were collected at 2- to 5-day intervals during the 30-day period around the peak in cereal aphid abundance, and the number of eggs they laid in the following 24 h in the laboratory was recorded. In addition to the number of eggs laid, clutch mass, live weight, and scutum width of ovipositing females and the sizes of the clutches laid in the field were recorded. As predicted, the reproductive allocation in both species was similar. The weight of the eggs of C. septempunctata (0.20 mg) and P. quatuordecimpunctata (0.18 mg) differed little, and the proportion of body mass allocated to daily reproduction (ca. 12%) was identical in both species. In addition, the maximum number of eggs laid per day in the field by the large species was, as predicted, greater than by the small species. Interestingly, the size of the egg clutches laid by C. septempunctata in the field was similar to the daily oviposition of field-collected adults recorded in the laboratory, whereas for P. quatuordecimpunctata it was significantly smaller. The role of morphology and physiology of ladybirds in structuring aphidophagous ladybird guilds is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Computational fluid dynamics (CFD) simulations are reported for flow, diffusion, reaction and heat transfer in a segment of an packed tube for the endothermic methane steam reforming reaction. The present work improves on previous approaches by explicit inclusion of intraparticle effects (conduction, species diffusion and reaction) coupled to realistic 3D external flow and temperature fields. It is shown that the usual assumption of symmetric species and temperature fields inside spherical catalyst particles holds for particles away from the tube wall, but particles placed in the strong temperature gradient near the tube wall show significant deviations. [Copyright &y& Elsevier]

A prominent interspecific pattern of sexual size dimorphism (SSD) is Rensch's rule, according to which male body size is more variable or evolutionarily divergent than female body size. Assuming equal growth rates of males and females, SSD would be entirely mediated, and Rensch's rule proximately caused, by sexual differences in development times, or sexual bimaturism (SBM), with the larger sex developing for a proportionately longer time. Only a subset of the seven arthropod groups investigated in this study exhibits Rensch's rule. Furthermore, we found only a weak positive relationship between SSD and SBM overall, suggesting that growth rate differences between the sexes are more important than development time differences in proximately mediating SSD in a wide but by no means comprehensive range of arthropod taxa. Except when protandry is of selective advantage (as in many butterflies, Hymenoptera, and spiders), male development time was equal to (in water striders and beetles) or even longer than (in drosophilid and sepsid flies) that of females. Because all taxa show female-biased SSD, this implies faster growth of females in general, a pattern markedly different from that of primates and birds (analyzed here for comparison). We discuss three potential explanations for this pattern based on life-history trade-offs and sexual selection. [ABSTRACT FROM AUTHOR]

BACKGROUND The reducing opposed multilobed (ROM) flap involves a series of transpositions effected cephalic and caudal to the primary defect, sequentially mobilized toward and then into the primary defect. OBJECTIVE To compare the ROM flap with other techniques to close defects below the knee after excision of skin tumor. METHOD This retrospective study compares 140 defects closed with a ROM flap with 85 defects closed with traditional techniques. RESULTS A total of 225 defects between 11 and 44 mm in diameter were excised over 3 years from July 1, 2002. There were 140 defects closed by ROM flap and 85 non-ROM closures including 29 “O-to-Z” flaps and 12 bilateral transposition flaps. A total of 111 squamous cell carcinomas, 64 basal cell carcinomas, and 11 melanoma were excised. ROM flap closures developed 20 complications (14.3%): 13 infections, 5 partial dehiscence, and 2 partial end flap necrosis. Non-ROM closures developed 27 complications (31.8%): 13 infections, 6 partial end flap necrosis, 4 partial dehiscence, 2 wound depression, 1 hemorrhage, and 1 persisting pain. Three ROM and 7 non-ROM cases suffered two complications. The total complication rate was significantly lower with ROM flaps ( p=.003), including lower end flap necrosis incidence ( p=.027). CONCLUSION The ROM flap results in fewer complications than traditional techniques when closing defects 11 to 45 mm in size on the leg and foot. In particular, end flap necrosis incidence is lower with ROM flap closure. [ABSTRACT FROM AUTHOR]

OBJECTIVE The study aimed to identify wound sites/procedures where infection incidence was over 5%, such that these circumstances may warrant wound infection antibiotic prophylaxis. METHOD We undertook a 3-year prospective study of 5,091 lesions (predominantly nonmelanoma skin cancer) treated on 2,424 patients from July 2002 to June 2005. No patient was given prophylactic antibiotics, and no patient ceased warfarin or aspirin. RESULTS Overall infection incidence was 1.47%. Individual procedures had the following infection incidence: curettage 0.73% (3/412); skin flap repairs 2.94% (47/1601); simple excision and closure 0.54% (16/2974); skin grafts 8.70% (6/69); and wedge excision 8.57% (3/35). Analysis of regions of the body demonstrated that surgery below the knee ( n=448) had an infection incidence of 6.92% (31/448) ( p<.0001). Subanalysis demonstrated that all regions below the knee were at high infection risk. Elsewhere, groin excisional surgery had an infection incidence of 10% (1/10) ( p=.027). No other body site demonstrated an infection incidence beyond 5% of statistical significance. Procedures on the face demonstrated an infection incidence of 0.81% (18/2,209). Diabetic patients, those on warfarin and/or aspirin, and smokers showed no difference in infection incidence. CONCLUSION Based on a prediction of infection incidence over 5%, the following cutaneous oncologic procedures warrant consideration of oral antibiotic wound infection prophylaxis: all procedures below the knee, wedge excisions of lip and ear, all skin grafts, and lesions in the groin. Other than under these circumstances, surgery to the nose, ear, fingers, lips, skin flap surgery, and surgery on diabetics, smokers, and those on anticoagulants have previously been considered for wound infection prophylaxis but do not warrant such intervention based on our data. [ABSTRACT FROM AUTHOR]

The quality of different species of aphids as food for aphidiphagous ladybird beetles varies greatly. The optimal oviposition theory predicts that a female should lay eggs preferentially in patches of suitable prey and should be reluctant to oviposit in patches of less suitable prey. A no-choice experiment was used to test whether aphids (Homoptera: Aphididae) of different suitability influence the oviposition behaviour of the two-spot ladybird beetle, Adalia bipunctata (L.) (Coleoptera: Coccinellidae). The results indicate that A. bipunctata females are not more reluctant to lay eggs in the presence of moderately suitable compared to highly suitable aphids. However, females laid fewer eggs in the presence of toxic aphids. [ABSTRACT FROM AUTHOR]

The author discusses the sentinel lymph node biopsy (SNB) as a means to eliminate the positive sentinel node prior to completion lymphadenectomy (CL). This concept and procedure developed by Morton et al promised the following: improved survival of melanoma patients, enhanced patient information and guidance for future management. The Multicenter Selective Lymphadenectomy Trial (MSLT-1) showed that SNB gave no survival benefits to the patients. The author further argues the limitations and disadvantages of the procedure.

Aphids and ants are two abundant and highly successful insect groups, which often live in the same habitat and therefore are likely to interact with one another. Whether the outcome of such an interaction is a predator-prey or mutualistic one is dependent on what each partner has to offer relative to the needs of the other. Consequently, understanding why some aphids enter mutualistic interactions with ants is dependent on understanding the physiological, ecological, and evolutionary traits of both partners. This includes an appreciation of the spatial, temporal, and taxonomic context in which mutualistic interactions developed. In this review, we use aphid-ant interactions to illustrate the whole range of interactions from antagonistic to mutualistic as well as to identify the processes affecting the degree of association and in particular the context within which such interactions evolved. The constraints of establishing and maintaining beneficial interactions between aphids and ants is addressed from a cost-benefit perspective. Prospects for future research are identified to further the understanding of the patterns and processes associated with aphid-ant relationships. [ABSTRACT FROM AUTHOR]

Abstract: A comparative study was made of the influence on heat transfer performance in the near-wall region, of internal voids in cylindrical particles, in a steam reforming packed bed reactor tube. Computational fluid dynamics (CFD) was used to obtain detailed flow and temperature fields in a representative wall segment of the tube. Simulations in which inert packing was heated up showed that particles with no internal voids appeared to perform better than particles with internal voids, in the bed interior. Near the wall, all particles behaved similarly. When heat sinks were included in the particles to represent the thermal effects of chemical reaction, the heat transfer performance of a packing of full cylinders was shown to change markedly, both qualitatively and quantitatively. [Copyright &y& Elsevier]

Following skin cancer excision, skin defects on the low leg between 10 and 35 mm in diameter can be problematic. Direct closure of the wound risks excessive wound tension and wound dehiscence. Skin grafts heal slowly and often remain unsightly. Traditional skin flaps have a limited role.The objective was to develop a random-pattern skin flap that offers significant advantages over traditional techniques including grafting.The reducing opposed multilobed flap involves a series of semicircular lobes extending both cephalic and caudal from the defect. The technique involves lobes most distant from the primary defect being transposed in turn closer to the defect. The technique does not result in the unnecessary excision of Burrows triangle skin.The reducing opposed multilobed (ROM) flap reduces skin tension concerns, lowers the risk of flap necrosis, and allows for quicker and more aesthetic healing. After 20 cases, we have yet to experience dehiscence, infection, or delayed healing. The healing wound is resistant to contraction and invariably produces an acceptable aesthetic outcome.The ROM flap repair allows the dermatologic surgeon an additional option when faced with a medium-sized lower leg defect following skin cancer excision.ANTHONY J. DIXON, MD, AND MARY P. DIXON HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [ABSTRACT FROM AUTHOR]

1. Dynamic models of optimal foraging predict that an animal's decision to accept or reject a patch depends not only on the environment and patch quality, but also on its internal state. Previous experiments have shown that the two-spot ladybird beetle,Adalia bipunctata(L.), is reluctant to lay eggs in a patch of prey contaminated by the oviposition-deterring pheromone produced by conspecific larvae.2. An experiment was conducted to test whether the internal state of anA. bipunctatafemale affects its oviposition response to oviposition-deterring pheromone. Firstly, the oviposition response to oviposition-deterring pheromone of young and old females was compared. Secondly, the oviposition response to oviposition-deterring pheromone of females previously exposed continuously to oviposition-deterring pheromone was compared with that of females of the same age but with no previous experience of oviposition-deterring pheromone.3. Old females and females with previous experience of oviposition-deterring pheromone were less reluctant to lay eggs in the presence of oviposition-deterring pheromone than young and naive females. These results are consistent with the predictions of optimal foraging theory. [ABSTRACT FROM AUTHOR]

1 Survival and development of hatchling larvae of three aphidophagous ladybirds (Coleoptera: Coccinellidae), Harmonia axyridis Pallas, Coccinella septempunctata brucki Mulsant and Adalia bipunctata Linnaeus, when fed their own and the other species eggs were recorded. 2 In all three species, the larvae survived when fed conspecific eggs. 3 The percentage of larvae of H. axyridis that survived decreased to 35% and 85% when fed eggs of A. bipunctata and C. s. brucki, respectively. All the larvae of A. bipunctata and C. s. brucki died after eating eggs of H. axyridis. None of the larvae of C. s. brucki died after eating eggs of A. bipunctata, whereas 46% of those of A. bipunctata died after eating eggs of C. s. brucki. 4 In general, larvae were reluctant to eat the eggs of other species. However, larvae of C. s. brucki showed less reluctance than H. axyridis to eat the eggs of A. bipunctata. 5 The consequence of this for invasive species of ladybird is discussed. [ABSTRACT FROM AUTHOR]

Abstract. 1. The incidence and timing of emigration, cannibalism, and intraguild predation of larvae of three aphidophagous ladybirds (Coleoptera: Coccinellidae), Harmonia axyridis Pallas, Coccinella septempunctata brucki Mulsant, and Propylea japonica Mulsant, relative to the presence of prey was determined in the laboratory in single- and mixed-species populations. 2. In single-species populations, 80% of the larvae of C. s. brucki emigrated prior to the extinction of the aphid population and no larvae were lost due to cannibalism; however > 80% of the larvae of the other two species were still present when the aphid became extinct and the losses due to cannibalism for H. axyridis and P. japonica were 25% and 14% respectively. Finally, 28% of the P. japonica larvae completed their development, whereas no larvae of the other two species became adult. 3. In mixed-species populations, mortality of P. japonica attributable to cannibalism or intraguild predation increased greatly to 60%, whereas that of the other two species remained about the same. Consequently, survival of H. axyridis larvae improved and survival of P. japonica worsened; however the survival of C. s. brucki larvae was not affected by the other two species. Early emigration by C. s. brucki larvae may have enabled them to escape intraguild predation by H. axyridis in this system. [ABSTRACT FROM AUTHOR]

1. The literature on ladybirds indicates that males are consistently smaller than females but take the same length of time to complete their development. Rearing Adalia bipunctata at 20 and 25 °C confirmed that protandry cannot account for sexual size dimorphism in this species, nor can a difference in egg size. 2. Female larvae consumed more food and had a higher relative growth rate in the fourth instar than did male larvae. 3. When food is limited, small males appear to be more successful at mating than are large males. 4. To account for these results, it is hypothesised that the gonads of male larvae compete more strongly with the soma for resources and that this reduces the growth potential of the soma of male larvae relative to that of female larvae. The greater mating success of small males when food is limited supports the eat or mate hypothesis, which predicts that when food is limited small males will spend less time feeding and more time mating than will large males. [ABSTRACT FROM AUTHOR]