Non-medical prescribing in critical care: A mixed methods study.

BACKGROUND: Little is known about non-medical prescribers in critical care in the United Kingdom. In 2007, a small survey identified few non-medical prescribers; however, in the intervening years, there have been many changes to the Medicine Act 1968. It is likely that prescribing within the non-medical workforce in critical care has changed significantly. AIM/S: This survey aimed to explore the breadth and diversity of prescribing practices of non-medical prescribers working within the wider critical care environment in the United Kingdom. METHOD: Data were collected via an online questionnaire adapted from the 2007 version and distributed by the BACCN to their members between 26th October 2021 and 19th November 2021. Freedom of Information requests were made to the Nursing and Midwifery Council, The Health and Care Professions Council and the General Pharmaceutical Council to understand the number of non-medical prescribers. RESULTS: The survey elicited 259 responses; 105 respondents identified themselves as non-medical prescribers, and 57 used Patient Group Directions only. In the ICU/HDU, 75 respondents identified as non-medical prescribers, with an additional 45 using Patient Group Directions. CONCLUSION: Since the last survey, there has been a large increase in the number and representation across all professional groups identifying as a non-medical prescriber and/or utilising patient group directions across critical care. Many staff responded to this survey who were neither NMPs nor utilising PGDs; of these, a large proportion were interested in taking on this additional responsibility. IMPLICATIONS FOR PRACTICE: Many people working within critical care are interested in becoming non-medical prescribers. Assists with understanding characteristics of those working as non-medical prescribers within critical care. Shows variations in practice in respect to PGDs, authorising of blood products and prescribing.

Resource competition drives an invasion-replacement event among shrew species on an island.

Invasive mammals are responsible for the majority of native species extinctions on islands. While most of these extinction events will be due to novel interactions between species (e.g. exotic predators and naive prey), it is more unusual to find incidences where a newly invasive species causes the decline/extinction of a native species on an island when they normally coexist elsewhere in their overlapping mainland ranges. We investigated if resource competition between two insectivorous small mammals was playing a significant role in the rapid replacement of the native pygmy shrew Sorex minutus in the presence of the recently invading greater white-toothed shrew Crocidura russula on the island of Ireland. We used DNA metabarcoding of gut contents from >300 individuals of both species to determine each species' diet and measured the body size (weight and length) during different stages of the invasion in Ireland (before, during and after the species come into contact with one another) and on a French island where both species have long coexisted (acting as a natural 'control' site). Dietary composition, niche width and overlap and body size were compared in these different stages. The body size of the invasive C. russula and composition of its diet changes between when it first invades an area and after it becomes established. During the initial stages of the invasion, individual shrews are larger and consume larger sized invertebrate prey species. During later stages of the invasion, C. russula switches to consuming smaller prey taxa that are more essential for the native species. As a result, the level of interspecific dietary overlap increases from between 11% and 14% when they first come into contact with each other to between 39% and 46% after the invasion. Here we show that an invasive species can quickly alter its dietary niche in a new environment, ultimately causing the replacement of a native species. In addition, the invasive shrew could also be potentially exhausting local resources of larger invertebrate species. These subsequent changes in terrestrial invertebrate communities could have severe impacts further downstream on ecosystem functioning and services.

The Accuracy of Post and Core Fabricated with Digital Technology.

PURPOSE: To compare the accuracy of post and cores created with three different fabricating techniques: direct conventional, machine milling, and three-dimensional (3D) printing. MATERIALS AND METHODS: Thirteen extracted single root central incisors were selected. Root canal treatment and tooth preparation for crown were performed on all teeth. Post space preparation of 11 mm was created using prefabricated fiber post drill to standardize post space width and length. Root canal impressions were performed on all teeth using polyvinyl siloxane impression material. Each impression was then three dimensionally scanned using an extraoral lab scanner. The scanned impressions were used to design digital files of post and cores with 3Shape CAD software. The digitally designed post and cores were used to fabricate 3D printed and milled post and core resin patterns. The same teeth were used to fabricate post and core with conventional technique (direct duplication of root canal with resin pattern). All posts were then scanned before being invested and then cast using base metal educational alloy. The metal post and cores were tried in with sample teeth and manually adjusted until found to be clinically acceptable. The post and cores were scanned in different stages to perform digital volume measurement using Geomagic Control software to determine accuracy. Pairwise comparisons were accomplished using exact version of the sign test (α = 0.05). RESULTS: These three techniques of post and core fabrication showed different results in the various stages of fabrication. The accuracy of 3D printed resin pattern (26.89 ±11.09 mm3 ) was found to be inferior compare to milled resin pattern (28.20 ±11.41 mm3 , p = 0.0002). However, dimensional stability of the 3D printed resin pattern before and after casting (0.56 ±0.95 mm3 ) was found to be superior to milled resin pattern (0.79 ±0.89 mm3 ) and direct resin pattern (2.51 ±1.38 mm3 , p = 0.00002). All three techniques showed significant volume reduction after adjustment (p = 0.0002). In the final stage, the adjusted metal post and core fabricated with three different techniques showed no statistical different in accuracy (p = 0.15). CONCLUSION: Digitally fabricated post and cores have the same degree of accuracy as those fabricated using the gold standard direct conventional post and core technique.

Genomic erosion in a demographically recovered bird species during conservation rescue.

The pink pigeon (Nesoenas mayeri) is an endemic species of Mauritius that has made a remarkable recovery after a severe population bottleneck in the 1970s to early 1990s. Prior to this bottleneck, an ex situ population was established from which captive-bred individuals were released into free-living subpopulations to increase population size and genetic variation. This conservation rescue led to rapid population recovery to 400-480 individuals, and the species was twice downlisted on the International Union for the Conservation of Nature (IUCN) Red List. We analyzed the impacts of the bottleneck and genetic rescue on neutral genetic variation during and after population recovery (1993-2008) with restriction site-associated sequencing, microsatellite analyses, and quantitative genetic analysis of studbook data of 1112 birds from zoos in Europe and the United States. We used computer simulations to study the predicted changes in genetic variation and population viability from the past into the future. Genetic variation declined rapidly, despite the population rebound, and the effective population size was approximately an order of magnitude smaller than census size. The species carried a high genetic load of circa 15 lethal equivalents for longevity. Our computer simulations predicted continued inbreeding will likely result in increased expression of deleterious mutations (i.e., a high realized load) and severe inbreeding depression. Without continued conservation actions, it is likely that the pink pigeon will go extinct in the wild within 100 years. Conservation rescue of the pink pigeon has been instrumental in the recovery of the free-living population. However, further genetic rescue with captive-bred birds from zoos is required to recover lost variation, reduce expression of harmful deleterious variation, and prevent extinction. The use of genomics and modeling data can inform IUCN assessments of the viability and extinction risk of species, and it helps in assessments of the conservation dependency of populations.

La paloma rosada (Nesoenas mayeri) es una especie endémica de Mauricio que se ha recuperado impresionantemente después de un grave cuello de botella poblacional a principios de la década de 1970 que duró hasta inicios de la década de 1990. Antes de este cuello de botella se había establecido una población ex situ de la cual se liberaban individuos reproducidos en cautiverio a las subpoblaciones en libertad para incrementar la variación genética y el tamaño poblacional. Este rescate de conservación derivó en una recuperación rápida de la población (400-480 individuos) y la especie cambió positivamente de categoría dos veces en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN). Analizamos los impactos del cuello de botella y el rescate genético sobre la variación genética neutral durante y después de la recuperación poblacional (de 1993 a 2008) mediante secuenciación RAD, análisis de microsatélites y análisis genéticos cuantitativos de los datos del libro genealógico de 1112 aves ubicadas en zoológicos de Europa y los Estados Unidos. Usamos simulaciones por computadora para estudiar los cambios pronosticados en la variación genética y en la viabilidad poblacional del pasado hacia el futuro. La variación genética declinó rápidamente, a pesar de la recuperación poblacional, y el tamaño efectivo de la población fue aproximadamente un orden de magnitud más pequeño que el tamaño del censo. La especie contó con una carga genética elevada de casi 15 equivalentes letales para la longevidad. Nuestras simulaciones pronostican que la endogamia continua probablemente resultará en un incremento en la expresión de mutaciones deletéreas (es decir, una carga realizada elevada) y en una depresión endogámica severa. Sin acciones continuas para la conservación, es probable que la paloma rosada esté extinta en vida libre dentro de cien años. El rescate de conservación de la paloma rosada ha sido fundamental en la recuperación de la población silvestre; sin embargo, se requiere de un rescate genético adicional con las aves de reproducción en cautiverio de los zoológicos para recuperar la variación perdida, reducir la expresión de la variación deletérea dañina y prevenir la extinción. El uso de la genómica y los datos modelados puede orientar las valoraciones de la UICN sobre la viabilidad y el riesgo de extinción de las especies, además de que ayuda en la evaluación de la dependencia que tienen las poblaciones de la conservación.

Assessing rates of parasite coinfection and spatiotemporal strain variation via metabarcoding: Insights for the conservation of European turtle doves Streptopelia turtur.

Understanding the frequency, spatiotemporal dynamics and impacts of parasite coinfections is fundamental to developing control measures and predicting disease impacts. The European turtle dove (Streptopelia turtur) is one of Europe's most threatened bird species. High prevalence of infection by the protozoan parasite Trichomonas gallinae has previously been identified, but the role of this and other coinfecting parasites in turtle dove declines remains unclear. Using a high-throughput sequencing approach, we identified seven strains of T. gallinae, including two novel strains, from ITS1/5.8S/ITS2 ribosomal sequences in turtle doves on breeding and wintering grounds, with further intrastrain variation and four novel subtypes revealed by the iron-hydrogenase gene. High spatiotemporal turnover was observed in T. gallinae strain composition, and infection was prevalent in all populations (89%-100%). Coinfection by multiple Trichomonas strains was rarer than expected (1% observed compared to 38.6% expected), suggesting either within-host competition, or high mortality of coinfected individuals. In contrast, coinfection by multiple haemosporidians was common (43%), as was coinfection by haemosporidians and T. gallinae (90%), with positive associations between strains of T. gallinae and Leucocytozoon suggesting a mechanism such as parasite-induced immune modulation. We found no evidence for negative associations between coinfections and host body condition. We suggest that longitudinal studies involving the recapture and investigation of infection status of individuals over their lifespan are crucial to understand the epidemiology of coinfections in natural populations.

Development of a multiplex microsatellite marker set for the study of the solitary red mason bee, Osmia bicornis (Megachilidae).

BACKGROUND: Solitary bees, such as the red mason bee (Osmia bicornis), provide important ecosystem services including pollination. In the face of global declines of pollinator abundance, such haplodiploid Hymenopterans have a compounded extinction risk due to the potential for limited genetic diversity. In order to assess the genetic diversity of Osmia bicornis populations, we developed microsatellite markers and characterised them in two populations. METHODS AND RESULTS: Microsatellite sequences were mined from the recently published Osmia bicornis genome, which was assembled from DNA extracted from a single male bee originating from the United Kingdom. Sequences were identified that contained dinucleotide, trinucleotide, and tetranucleotide repeat regions. Seventeen polymorphic microsatellite markers were designed and tested, sixteen of which were developed into four multiplex PCR sets to facilitate cheap, fast and efficient genotyping and were characterised in unrelated females from Germany (n = 19) and England (n = 14). CONCLUSIONS: The microsatellite markers are highly informative, with a combined exclusion probability of 0.997 (first parent), which will enable studies of genetic structure and diversity to inform conservation efforts in this bee.

Multisource noninvasive genetics of brown bears (Ursus arctos) in Greece reveals a highly structured population and a new matrilineal contact zone in southern Europe.

In human-dominated landscapes, connectivity is crucial for maintaining demographically stable mammalian populations. Here, we provide a comprehensive noninvasive genetic study for the brown bear population in the Hellenic Peninsula. We analyze its population structuring and connectivity, estimate its population size throughout its distribution, and describe its phylogeography in detail for the first time. Our results, based on 150 multilocus genotypes and on 244-bp sequences of the mtDNA control region, show the population is comprised by three highly differentiated genetic clusters, consistent with geographical populations of Pindos, Peristeri, and Rhodope. By detecting two male bears with Rhodopean ancestry in the western demes, we provide strong evidence for the ongoing genetic connectivity of the geographically fragmented eastern and western distributions, which suggests connectivity of the larger East Balkan and Pindos-Dinara populations. Total effective population size (N e) was estimated to be 199 individuals, and total combined population size (N C) was 499, with each cluster showing a relatively high level of genetic variability, suggesting that migration has been sufficient to counteract genetic erosion. The mtNDA results were congruent with the microsatellite data, and the three genetic clusters were matched predominantly with an equal number of mtDNA haplotypes that belong to the brown bear Western mitochondrial lineage (Clade 1), with two haplotypes being globally new and endemic. The detection of a fourth haplotype that belongs to the Eastern lineage (Clade 3a1) in three bears from the western distribution places the southernmost secondary contact zone between the Eastern and Western lineages in Greece and generates new hypotheses about postglacial maxima migration routes. This work indicates that the genetic composition and diversity of Europe's low-latitude fringe population are the outcome of ancient and historical events and highlight its importance for the connectivity and long-term persistence of the species in the Balkans.

Open versus percutaneous tracheostomy in COVID-19: a multicentre comparison and recommendation for future resource utilisation.

PURPOSE: The COVID-19 pandemic placed an unprecedented demand on critical care services for the provision of mechanical ventilation. Tracheostomy formation facilitates liberation from mechanical ventilation with advantages for both the patient and wider critical care resource, and can be performed using both percutaneous dilatational and surgical techniques. We compared outcomes in those patients undergoing percutaneous dilatational tracheostomy to those undergoing surgical tracheostomy and make recommendations for provision of tracheostomy services in any future surge. METHODS: Multicentre multidisciplinary retrospective observational cohort study including 201 patients with COVID-19 pneumonitis admitted to an ICU in one of five NHS Trusts within the South London Adult Critical Care Network who required mechanical ventilation and subsequent tracheostomy. RESULTS: Percutaneous dilatational tracheostomy was performed in 124 (62%) of patients, and surgical tracheostomy in 77 (38%) of patients. There was no difference between percutaneous dilatational tracheostomy and surgical tracheostomy in either the rate of peri-operative complications (16.9 vs. 22.1%, p = 0.46), median [IQR(range)] time to decannulation [19.0 (15.0-30.2 (5.0-65.0)] vs. 21.0 [15.5-36.0 (5.0-70.0) days] or mortality (13.7% vs. 15.6%, p = 0.84). Of the 172 patients that were alive at follow-up, two remained ventilated and 163 were decannulated. CONCLUSION: In patients with COVID-19 pneumonitis that require tracheostomy to facilitate weaning from mechanical ventilation, there was no difference in outcomes between those patients that had percutaneous dilatational tracheostomy compared with those that had surgical tracheostomy. Planning for future surges in COVID-19-related critical care demands should utilise all available resource and expertise.

Crystalline phase evolution and thermal behavior of zirconia-lanthanum aluminate ceramics produced by surface modification.

The purpose of the present work was to investigate the effect doping with lanthanum aluminate on the phase assemblage and thermal behavior of zirconia ceramics for biomedical applications. Four compositions were prepared by a surface modification route of either conventional tetragonal zirconia (3Y-TZP) or high translucency cubic-based zirconia (5Y-PSZ) to reach a nominal composition of either 0.5 wt. % (3Y-0.5LAO and 5Y-0.5LAO) or 5 wt. % of lanthanum monoaluminate (3Y-5LAO and 5Y-5LAO). Undoped powders were used as controls. DTA and XRD analyses revealed that lanthanum dizirconate crystallized in the 934°C-936°C range, while lanthanum aluminate crystallized in the 1,056°C-1,063°C range in both types of zirconias doped at the 5% level. No second phase was found in compositions doped at the 0.5% level. The a lattice parameter and the amount of the cubic phase increased in both 3Y-5LAO and 5Y-5LAO. The microstructure of the compositions doped with 5% LAO was characterized by well distributed LAO twinned crystals and sparse needle-shaped lanthanum hexaaluminate crystals. A bimodal grain size distribution was observed in 5Y-doped compositions. This was attributed to abnormal grain growth of the cubic phase, and in line with aluminum segregation at grain boundaries and the presence of second-phase LAO crystals.

Tracheostomy care and decannulation during the COVID-19 pandemic. A multidisciplinary clinical practice guideline.

PURPOSE: Traditional critical care dogma regarding the benefits of early tracheostomy during invasive ventilation has had to be revisited due to the risk of COVID-19 to patients and healthcare staff. Standard practises that have evolved to minimise the risks associated with tracheostomy must be comprehensively reviewed in light of the numerous potential episodes for aerosol generating procedures. We meet the urgent need for safe practise standards by presenting the experience of two major London teaching hospitals, and synthesise our findings into an evidence-based guideline for multidisciplinary care of the tracheostomy patient. METHODS: This is a narrative review presenting the extensive experience of over 120 patients with tracheostomy, with a pragmatic analysis of currently available evidence for safe tracheostomy care in COVID-19 patients. RESULTS: Tracheostomy care involves many potentially aerosol generating procedures which may pose a risk of viral transmission to staff and patients. We make a series of recommendations to ameliorate this risk through infection control strategies, equipment modification, and individualised decannulation protocols. In addition, we discuss the multidisciplinary collaboration that is absolutely fundamental to safe and effective practise. CONCLUSION: COVID-19 requires a radical rethink of many tenets of tracheostomy care, and controversy continues to exist regarding the optimal techniques to minimise risk to patients and healthcare workers. Safe practise requires a coordinated multidisciplinary team approach to infection control, weaning and decannulation, with integrated processes for continuous prospective data collection and audit.

Effect of crystalline phase assemblage on reliability of 3Y-TZP.

STATEMENT OF PROBLEM: Strengthening mechanisms of zirconia ceramics stabilized with 3 mol% yttria (3Y-TZP) are complex and dictated by the crystalline phase assemblage. Although their clinical performance for dental restorations has been excellent, there is evidence that framework fractures do occur and have been underreported. Meanwhile, the relationship between phase assemblage and reliability of 3Y-TZP is not properly understood. PURPOSE: The purpose of this in vitro study was to elucidate the relationship between crystalline phase assemblage and the reliability of 3Y-TZP and to calculate the associated probabilities of survival. MATERIAL AND METHODS: Disks of 3Y-TZP were prepared from cylindrical blanks and randomly assigned to 12 experimental groups (n=20 per group). Different crystalline phase assemblages were produced by either varying the sintering temperature from 1350 °C to 1600 °C and/or treating the surface by airborne-particle abrasion with 50-mm alumina particles at a pressure of 0.2 MPa for 1 minute with or without subsequent heat treatment. Crystalline phases were analyzed by standard and grazing incidence X-ray diffraction (GIXRD). The relationship between phase assemblage and reliability was determined by measuring the biaxial flexural strength (BFS) according to ISO standard 6872 and by using Weibull statistics to calculate the Weibull modulus (m), probability of survival, and maximum allowable stresses. XRD results were analyzed by ANOVA to detect statistically significant differences between groups. Adjustment for all pairwise group comparisons was made using the Tukey method (α=.05). RESULTS: Standard incidence XRD confirmed the presence of a small amount of cubic phase after sintering at 1350 °C. A cubic-derived nontransformable tetragonal t'-phase was observed at sintering temperatures of 1450 °C and above, the amount of which increased linearly. GIXRD revealed that airborne-particle abraded groups sintered at 1350 °C and 1600 °C had the highest variability in monoclinic phase fraction as a function of depth. These groups were also associated with the lowest reliability. Groups as-sintered at 1350 °C and 1600 °C had the lowest modulus (m=8.1 [0.5] and 7.0 [0.8], respectively) and probability of survival (Ps) for a maximum allowable stress of 700 MPa, while treated groups sintered at 1450 °C and 1550 °C were associated with the highest modulus (from 15.0 [1.4] to 20.9 [1.4]) and Ps (≥0.9999). The lower strength and reliability of groups sintered at 1600 °C was consistent with the presence of a significant amount of nontransformable t'-phase. The pattern of BFS results indicated that ferro-elastic domain switching was a dominant strengthening mechanism in 3Y-TZP. CONCLUSIONS: The present study first reported on the detrimental effect of the cubic-derived nontransformable t'-phase on the mechanical properties of 3Y-TZP. It was demonstrated that phase assemblage determined reliability and was directly linked to the probability of survival.

Spatio-temporal processes drive fine-scale genetic structure in an otherwise panmictic seabird population.

When and where animals breed can shape the genetic structure and diversity of animal populations. The importance of drivers of genetic diversity is amplified in island populations that tend to have more delineated gene pools compared to continental populations. Studies of relatedness as a function of the spatial distribution of individuals have demonstrated the importance of spatial organisation for individual fitness with outcomes that are conditional on the overall genetic diversity of the population. However, few studies have investigated the impact of breeding timing on genetic structure. We characterise the fine-scale genetic structure of a geographically-isolated population of seabirds. Microsatellite markers provide evidence for largely transient within-breeding season temporal processes and limited spatial processes, affecting genetic structure in an otherwise panmictic population of sooty terns Onychoprion fuscatus. Earliest breeders had significantly different genetic structure from the latest breeders. Limited evidence was found for localised spatial structure, with a small number of individuals being more related to their nearest neighbours than the rest of the population. Therefore, population genetic structure is shaped by heterogeneities in collective movement in time and to a lesser extent space, that result in low levels of spatio-temporal genetic structure and the maintenance of genetic diversity.

Investigation into Adaptation in Genes Associated with Response to Estrogenic Pollution in Populations of Roach (Rutilus rutilus) Living in English Rivers.

Exposure of male fish to estrogenic substances from wastewater treatment works (WwTWs) results in feminization and reduced reproductive fitness. Nevertheless, self-sustaining populations of roach (Rutilus rutilus) inhabit river stretches polluted with estrogenic WwTW effluents. In this study, we examine whether such roach populations have evolved adaptations to tolerate estrogenic pollution by comparing frequency differences in single-nucleotide polymorphisms (SNPs) between populations sampled from rivers receiving either high- or low-level WwTW discharges. SNPs within 36 "candidate" genes, selected for their involvement in estrogenic responses, and 120 SNPs in reference genes were genotyped in 465 roaches. There was no evidence for selection in highly estrogen-dependent candidate genes, including those for the estrogen receptors, aromatases, and vitellogenins. The androgen receptor (ar) and cytochrome P450 1A genes were associated with large shifts in allele frequencies between catchments and in individual populations, but there is no clear link to estrogen pollution. Selection at ar in the effluent-dominated River Lee may have resulted from historical contamination with endocrine-disrupting pesticides. Critically, although our results suggest population-specific selection including at genes related to endocrine disruption, there was no strong evidence that the selection resulted from exposure to estrogen pollution.

Heritability and correlations among learning and inhibitory control traits.

To understand the evolution of cognitive abilities, we need to understand both how selection acts upon them and their genetic (co)variance structure. Recent work suggests that there are fitness consequences for free-living individuals with particular cognitive abilities. However, our current understanding of the heritability of these abilities is restricted to domesticated species subjected to artificial selection. We investigated genetic variance for, and genetic correlations among four cognitive abilities: inhibitory control, visual and spatial discrimination, and spatial ability, measured on >450 pheasants, Phasianus colchicus, over four generations. Pheasants were reared in captivity but bred from adults that lived in the wild and hence, were subject to selection on survival. Pheasant chicks are precocial and were reared without parents, enabling us to standardize environmental and parental care effects. We constructed a pedigree based on 15 microsatellite loci and implemented animal models to estimate heritability. We found moderate heritabilities for discrimination learning and inhibitory control (h2 = 0.17-0.23) but heritability for spatial ability was low (h2 = 0.09). Genetic correlations among-traits were largely positive but characterized by high uncertainty and were not statistically significant. Principle component analysis of the genetic correlation matrix estimate revealed a leading component that explained 69% of the variation, broadly in line with expectations under a general intelligence model of cognition. However, this pattern was not apparent in the phenotypic correlation structure which was more consistent with a modular view of animal cognition. Our findings highlight that the expression of cognitive traits is influenced by environmental factors which masks the underlying genetic structure.

Antimicrobial efficacy of platinum-doped silver nanoparticles.

Silver nanoparticles (AgNPs) have been proposed to combat oral infection due to their efficient ionic silver (Ag+ ) release. However, concentrations required for antimicrobial efficacy may not be therapeutically viable. In this work, platinum-doped silver nanoparticles (Pt-AgNPs) were explored to evaluate their potential for enhanced Ag+ release, which could lead to enhanced antimicrobial efficacy against S. aureus, P. aeruginosa, and E. coli. AgNPs doped with 0.5, 1, and 2 mol% platinum (Pt0.5 -AgNPs, Pt1 -AgNPs, and Pt2 -AgNPs) were synthesized by a chemical reduction method. Transmission electron microscopy revealed mixed morphologies of spherical, oval, and ribbon-like nanostructures. Surface-enhanced Raman scattering revealed that the surface of Pt-AgNPs was covered with up to 93% Pt. The amount of Ag+ released increased 16.3-fold for Pt2 -AgNPs, compared to AgNPs. The initial lag phase in bacterial growth curve was prolonged for Pt-AgNPs. This is consistent with a Ag+ release profile that exhibited an initial burst followed by sustained release. Doping AgNPs with platinum significantly increased the antimicrobial efficacy against all species. Pt2 -AgNPs exhibited the lowest minimum inhibitory concentrations, followed by Pt1 -AgNPs, Pt0.5 -AgNPs, and AgNPs, respectively. Doping AgNPs with a small amount of platinum promoted the release of Ag+ , based on the sacrificial anodic effect, and subsequently enhanced their antimicrobial efficacy.

Clinical Versus Radiographic Caries Diagnosis in Primary Tooth Approximal Surfaces.

Purpose: The purpose of this study was to compare approximal carious lesions in dentin diagnosed by clinical examination with those diagnosed radiographically in high caries-risk children. Methods: Eighty-four Amish two- to 11-year-olds were evaluated clinically by calibrated examiners using standard epidemiological criteria and radiographically using standard criteria as part of baseline examinations for a two-year pilot clinical trial. Approximal carious surfaces diagnosed by clinical examination were compared to those diagnosed radiographically to determine the number of lesions misdiagnosed by clinical examination alone. Comparisons between the number of lesions detected by clinical exam and radiographic exam were made using McNemar's test. Results: Among 124 anterior approximal tooth surfaces, clinical examination alone identified 61 lesions (49.2 percent), while radiograph examination identified 72 lesions (58.1 percent); thus, nine percent of lesions were misdiagnosed by clinical examination alone. For the 412 posterior approximal tooth surfaces included in the study, 101 lesions (24.5 percent) were identified by clinical examination, whereas 229 lesions (55.6 percent) were identified via radiographic examination. Thus, 128 (31.1 percent) were misdiagnosed by clinical examination alone. Conclusions: Clinical examinations without radiographs significantly underestimate caries prevalence. Therefore, the use of radiographs should be encouraged in epidemiological studies and clinical trials.

Comparison of the Accuracy of Implant Position Using Surgical Guides Fabricated by Additive and Subtractive Techniques.

PURPOSE: To evaluate the accuracy of implant position using surgical guides fabricated by additive and subtractive techniques. MATERIALS AND METHODS: A partially edentulous standardized mandibular implant model with different bone densities and soft tissue was duplicated and a diagnostic wax-up was performed for the #30 area. A reference radiographic guide was fabricated and cone beam computed tomography (CBCT) was made with the reference radiographic guide in place. A surgical guide was designed using BlueSky Plan 4 software and a reference implant was placed in the #30 region. The STL file of the surgical guide was exported and specimens (n = 15) were fabricated by two different techniques: additive (3D printing) and subtractive (milling). The standardized mandibular model was surface-scanned and duplicated with printed dental model resin (n = 30). Each surgical guide was used to place an implant in thirty duplicate printed models. Differences in implant position as compared to the reference were measured from digital scans with scan bodies in place. The angular deviations, differences in depth, coronal and apical deviations were measured using GeoMagic Control X software. Results were analyzed by Wilcoxon-Mann-Whitney test and PERMANOVA (Permutational Multivariate Analysis of Variance). Intraclass correlation was used to assess measurement reproducibility with Bonferroni adjustment for multiple testing as needed (α = 0.05). RESULTS: There were no significant differences in accuracy of implant placement using guides fabricated using additive vs subtractive techniques. The mean angular deviations between the reference and actual position of implant in mesio-distal cross-section were 0.780 ± 0.80° for printed group and 0.77 ± 0.72° for the milled group. The differences in bucco-lingual cross-section were 1.60 ± 1.22° in in printed group and 1.77 ± 0.76° in the milled group. The differences in depth (mm) were measured at the top of the scan body at four locations: mesial, distal, buccal and lingual. The mean differences in depth for the group that used printed surgical guides were (mesial) 0.37 ± 0.29 mm, (distal) 0.32 ± 0.23 mm, (buccal) 0.24 ± 0.23 mm, and (lingual) 0.25 ± 0.17 mm. The mean differences in depth for the group that used milled surgical guides were (mesial) 0.51 ± 0.33 mm, (distal) 0.40 ± 0.32 mm, (buccal) 0.22 ± 0.23 mm, and (lingual) 0.23 ± 0.12 mm in those four aspects, respectively. The mean coronal deviation showed 0.32 mm in the printed group and 0.27 mm in the milled group. For the apical deviation, the results of this study showed mean apical deviation 0.84 mm in the printed group and 0.80 mm in the milled group. CONCLUSIONS: Results indicate that 3D-printed surgical guides are statistically as accurate as milled guides for guided-implant surgery with the benefits of high accuracy, ease of fabrication, less waste compared to subtractive techniques, and reduction of laboratory time thereby increasing cost-effectiveness.

Spatio-temporal genetic tagging of a cosmopolitan planktivorous shark provides insight to gene flow, temporal variation and site-specific re-encounters.

Migratory movements in response to seasonal resources often influence population structure and dynamics. Yet in mobile marine predators, population genetic consequences of such repetitious behaviour remain inaccessible without comprehensive sampling strategies. Temporal genetic sampling of seasonally recurring aggregations of planktivorous basking sharks, Cetorhinus maximus, in the Northeast Atlantic (NEA) affords an opportunity to resolve individual re-encounters at key sites with population connectivity and patterns of relatedness. Genetic tagging (19 microsatellites) revealed 18% of re-sampled individuals in the NEA demonstrated inter/multi-annual site-specific re-encounters. High genetic connectivity and migration between aggregation sites indicate the Irish Sea as an important movement corridor, with a contemporary effective population estimate (Ne) of 382 (CI = 241-830). We contrast the prevailing view of high gene flow across oceanic regions with evidence of population structure within the NEA, with early-season sharks off southwest Ireland possibly representing genetically distinct migrants. Finally, we found basking sharks surfacing together in the NEA are on average more related than expected by chance, suggesting a genetic consequence of, or a potential mechanism maintaining, site-specific re-encounters. Long-term temporal genetic monitoring is paramount in determining future viability of cosmopolitan marine species, identifying genetic units for conservation management, and for understanding aggregation structure and dynamics.