Hasil untuk "United States"

Cynthia Avedian, Christina D. M. Trang, Michael S. Inkpen

Marcos Gabriel Mendes Lauande, Geraldo Braz Júnior, João Dallyson Sousa de Almeida et al.

Penile cancer has an incidence strongly linked to sociocultural factors, being more common in underdeveloped countries like Brazil, where it represents approximately 2% of cancers affecting men. This dataset was created to address the scarcity of publicly available resources for classifying histopathological images in penile cancer research. The images were collected in 2021 from tissue samples obtained through biopsies of patients undergoing treatment for penile cancer. After staining with Hematoxylin and Eosin (H&E), the tissue samples were photographed using a Leica ICC50 HD camera attached to a bright-field microscope (Leica DM500). The dataset comprises 194 high-resolution images (2048 × 1536 pixels), categorized by magnification (40X and 100X) and pathological classification (Tumor or Non-Tumor). Metadata includes additional information such as histological grade and, for some images, HPV status. Although previous works have focused primarily on binary classification tasks, the dataset includes additional labels, such as histological grade and HPV (Human Papilloma Virus) presence, which provide opportunities for multi-label classification or other types of predictive modelling. These extended labels enhance the dataset’s versatility for more complex tasks in medical image analysis. The dataset holds significant reuse potential for machine learning tasks beyond binary classification, allowing researchers to explore additional layers of analysis, such as HPV detection and histological grading. It can also be used for model benchmarking and comparative studies in cancer research, contributing to developing new diagnostic tools. The dataset and metadata are available for further research and model development.

Gengyang Li, Mason Peng, Qingguo Huang et al.

Per- and polyfluoroalkyl substances (PFAS) have drawn public concern recently due to their toxic properties and persistence in the environment, making it urgent to eliminate PFAS from contaminated water. Electrochemical oxidation (EO) has shown great promise for the destructive treatment of PFAS with direct electron transfer and hydroxyl radical (⋅OH)-mediated indirect reactions. One of the most popular electrodes is Magnéli phase titanium suboxides. However, the degradation mechanisms of PFAS are still unsure and are under investigation now. The main methodology is the first-principal density functional theory (DFT) computation, which is recently used to explore the degradation mechanisms and interpret by-product formation during PFAS mineralization. From the literature review, the main applications of DFT computation for studying PFAS degradation mechanisms by EO include bond dissociation energy, absorption energy, activation energy, and overpotential η for oxygen evolution reactions. The main degradation mechanisms and pathways of PFAS in the EO process include mass transfer, direct electron transfer, decarboxylation, peroxyl radical generation, hydroxylation, intramolecular rearrangement, and hydrolysis. In the recent 4 years, 11 papers performed DFT computation to explore the possible PFAS degradation mechanisms and pathways in the EO process. This paper’s objectives are to: 1) summarize the main degradation mechanisms of PFAS degradation in EO; 2) review the application of DFT computation for studying PFAS degradation mechanisms during EO; process; 3) review the possible degradation pathways of perfluorooctane sulfonoic acid (PFOS) and per-fluorooctanoic acid (PFOA) during EO process.

Tao Wang, Qi Luo, Fengyuan Cui et al.

Given the recent success of metasurfaces in free-space applications, these concepts can be leveraged to an even larger extent in on-chip waveguide systems. The in-plane diffractive metasurfaces enable the manipulation of guiding waves in the multimode regime with greater parallelism than conventional single-mode or few-mode waveguides, leading to exciting opportunities in signal processing and optical computing systems. Beam focusing is one of the basic functionalities of wavefront shaping, which can be implemented using phase gradient metalenses consisting of arrays of meta-atoms. The meta-atoms are mainly realized by etched trenches with varying lengths, which are assembled into a one-dimensional transmit array with a specific phase response. However, this kind of periodic arrayed structure has significantly limited design freedom compared to its free-space counterparts. Here, we propose a digital metalens that consists of a seamless array of pixelated unit cells, which are engineered via inverse design. In contrast to conventional focusing metalenses based on transmit arrays, highly functional digital metalenses have been demonstrated: (1) achromatic focusing lens; (2) extended depth of focus (EDOF) lens; (3) Airy beam lens. These devices were fabricated on a silicon photonic platform and characterized in near-infrared. The intersection of digital structures and algorithm-driven optimizations offers greater versatility for on-chip wavefront shaping.

Seyyed Khalil HosseiniHashemi, Ahad Rahimi, Nadir Ayrilmis

Polypropylene (PP) with black locust wood flour and maleic grafted polypropylene were used to prepare wood plastic composites (WPC) by injection molding. The effect of the addition of nano titanium oxide (nano TiO2) on the properties of the composites was investigated. The specimens were weathered in an accelerated weathering apparatus using a xenon arc lamp for 2000 h. The physical properties of the composites were evaluated by colorimetry, water absorption, and thickness swelling before and after weathering. Mechanical properties of WPC were also determined before and after weathering. The WPC containing 0.75 phr nano TiO2 showed an improvement in the flexural and tensile strength and flexural and tensile modulus while the WPCs containing 0.2 phr nano TiO2 showed an improvement in the impact strength. The UV resistance of the WPCs also improved with the incorporation of nano TiO2 powder into the composites. Both water absorption and thickness swelling were found to be reduced by the incorporation of nano TiO2 into WPC.

Ya-Wen Peng, Ri Tang, Qiao-Yi Xu et al.

Background: Fibrosis is a heavy burden on the global healthcare system. Recently, an increasing number of studies have demonstrated that Extracellular vesicles play an important role in intercellular communication under both physiological and pathological conditions. This study aimed to explore the role of extracellular vesicles’ in fibrosis using bibliometric methods. Methods: Original articles and reviews related to extracellular vesicles and fibrosis were obtained from the Web of Science Core Collection database on November 9, 2022. VOSviewer was used to obtain general information, including co-institution, co-authorship, and co-occurrence visualization maps. The CiteSpace software was used to analyze citation bursts of keywords and references, a timeline view of the top clusters of keywords and cited articles, and the dual map. R package ''bibliometrix'' was used to analyze annual production, citation per year, collaboration network between countries/regions, thematic evolution map, and historiography network. Results: In total, 3376 articles related to extracellular vesicles and fibrosis published from 2013 to 2022 were included in this study, with China and the United States being the top contributors. Shanghai Jiao Tong University has the highest number of publications. The main collaborators were Giovanni Camussi, Stefania Bruno, Marta Tepparo, and Cristina Grange. Journals related to molecular, biology, genetics, health, immunology, and medicine tended to publish literature on extracellular vesicles and fibrosis. “Recovery,” “heterogeneity,” “degradation,” “inflammation,” and “mesenchymal stem cells” are the keywords in this research field. Literature on extracellular vesicles and fibrosis associated with several diseases, including “kidney disease,” “rheumatoid arthritis,” and “skin regeneration” may be the latest hot research field. Conclusions: This study provides a comprehensive perspective on extracellular vesicles and fibrosis through a bibliometric analysis of articles published between 2013 and 2022. We identified the most influential countries, institutions, authors, and journals. We provide information on recent research frontiers and trends for scholars interested in the field of extracellular vesicles and fibrosis. Their role in biological processes has great potential to initiate a new upsurge in future research.

Tanawin Sakarin, Tippawan Liabsuetrakul

Abstract Objective To assess the dispositions, management, and clinical outcomes of TIAMS patients in ED to improve the quality of management in ED. Material and Method A descriptive retrospective study was conducted in ED patients aged >18 years diagnosed with TIAMS in the ED from 1 January 2018, to 31 January 2019. Data regarding terms of clinical presentation, examination, management, disposition, and adverse events were collected. Results Three hundred and sixty‐three TIAMS patients were enrolled in the study. Majority of the patients aged <45 years were admitted or referred (15.4%). The highest proportion of patients whose onset times from the last normal were less than 4.5 h were admitted to the EDOU (55.6%), while all patients whose onset times from the last normal were more than 48 h were discharged. Patients with abnormal cerebellar signs or atrial fibrillation were less likely to be discharged from the hospital. Patients with lower National Institutes of Health Stroke Scale (NIHSS) and ABCD2 scores tended to be discharged. Conclusion Among TIAMS patients, age, symptom onset, presence of atrial fibrillation, positive cerebellar signs, and severity scores influenced the disposition. There was no difference in adverse events among disposition groups.

Kun He, Jiayu Lin, Yulei Liang et al.

ABSTRACT The interaction between coexisting plasmids can affect plasmid-carried resistance gene persistence and spread. However, whether the persistence of the blaCTX-M gene in clinical Enterobacteriaceae is related to the interaction of coresident nonresistance-conferring plasmids has not been reported. This study was initiated to elucidate how a nonresistance-conferring IncI1 plasmid affected the blaCTX-M-bearing IncFII plasmid colocated on the same cell. Herein, we constructed three isogenic derivatives of E. coli C600, designated as C600FII, C600I1, and C600FII+I1, which harbored the blaCTX-M-IncFII plasmid and/or the nonresistance-IncI1 one. We discovered that strain C600FII+I1 conferred higher fitness advantages than strain C600FII; also, the stability of the blaCTX-M-IncFII plasmid was noticeably improved in an antibiotic-free environment when it coexisted with the IncI1 plasmid. To further explore why the IncI1 plasmid enhanced the persistence of the blaCTX-M-IncFII plasmid, we assessed the blaCTX-M-IncFII plasmid's copy numbers, conjugation frequencies, and rep gene expressions in strains C600FII and C600FII+I1. The results demonstrated that the rep expressions of the blaCTX-M-IncFII plasmid in strain C600FII+I1 was greatly decreased, along with the plasmid’s copy numbers and mating efficiencies, compared to those in strain C600FII. Moreover, further study revealed that the intracellular ATP levels of strain C600FII+I1 were far lower than those of strain C600FII. Our findings confirmed that coexistence of the nonresistance-IncI1 plasmid can keep the blaCTX-M-IncFII plasmid more stable by increasing the fitness advantages of the host bacteria, which will pose a threat to preventing the long-term presence of the plasmid-carried blaCTX-M gene in clinical Enterobacteriaceae.IMPORTANCESo far, plasmid-carried blaCTX-M is still the most common extended-spectrum beta-lactamase (ESBL) genotype in clinical settings worldwide. Except for the widespread use of third-generation cephalosporins, the interaction between coexisting plasmids can also affect the long-term stable existence of the blaCTX-M gene; however, the study on that is still sparse. In the present study, we assess the interaction of coinhabitant plasmids blaCTX-M-IncFII and nonresistance-IncI1. Our results confirmed that the increased fitness advantages of strain C600FII+I1 were attributable to the cohabitant nonresistance-IncI1 plasmid, which largely reduced the intracellular ATP levels of host bacteria, thus decreasing the rep gene expression of the blaCTX-M-IncFII plasmid, its copy numbers, and mating efficiencies, while the higher fitness advantages of strain C600FII+I1 enhanced the persistence of the blaCTX-M-IncFII plasmid. The results indicate that the nonresistance-IncI1 plasmid contributes to the long-term existence of the blaCTX-M-IncFII plasmid, implying a potentially new strategy for controlling the spread of resistance plasmids in clinical settings by targeting nonresistance plasmids.

Scott Mastromatteo, Angela Chen, Jiafen Gong et al.

Summary: Phasing of heterozygous alleles is critical for interpretation of cis-effects of disease-relevant variation. We sequenced 477 individuals with cystic fibrosis (CF) using linked-read sequencing, which display an average phase block N50 of 4.39 Mb. We use these samples to construct a graph representation of CFTR haplotypes, demonstrating its utility for understanding complex CF alleles. These are visualized in a Web app, CFTbaRcodes, that enables interactive exploration of CFTR haplotypes present in this cohort. We perform fine-mapping and phasing of the chr7q35 trypsinogen locus associated with CF meconium ileus, an intestinal obstruction at birth associated with more severe CF outcomes and pancreatic disease. A 20-kb deletion polymorphism and a PRSS2 missense variant p.Thr8Ile (rs62473563) are shown to independently contribute to meconium ileus risk (p = 0.0028, p = 0.011, respectively) and are PRSS2 pancreas eQTLs (p = 9.5 × 10−7 and p = 1.4 × 10−4, respectively), suggesting the mechanism by which these polymorphisms contribute to CF. The phase information from linked reads provides a putative causal explanation for variation at a CF-relevant locus, which also has implications for the genetic basis of non-CF pancreatitis, to which this locus has been reported to contribute.

Danelle Agnew, Kirstie Fryirs

By connecting corridors of river recovery, resilience can be built into river systems to mitigate against future floods and droughts driven by anthropogenic disturbance or climate extremes. However, identifying where these corridors can be built is still lacking in river management practice. The Open Access NSW River Styles database contains comprehensive information on geomorphic river condition and recovery potential. The database can be used to systematically analyse where corridors of river recovery could be created via conservation or rehabilitation. Analysis was undertaken in ArcGIS using the recovery potential layer along 84,342 km of freshwater stream length, across 20 catchments of coastal NSW. We identified 4,905 km of reach connections, defined as an upstream to downstream section of river that is connected end-to-end, and 17,429 km of loci connections defined as more isolated sections of river from which recovery can be seeded and extended into adjacent reaches. There was significant spatial variability in the types and lengths of connections made across the catchments. Some catchments have significant potential to build corridors of recovery along large sections of river, whereas other catchments are more fragmented. These results provide practitioners with a user-friendly distillation of where river conservation and rehabilitation activities could be focussed when working with river recovery in practice. Combined with local on-ground knowledge, this information forms an important input to evidence-based prioritisation and decision making in river management.

Karen Filbee-Dexter, Colette J. Feehan, Dan A. Smale et al.

Cycling of organic carbon in the ocean has the potential to mitigate or exacerbate global climate change, but major questions remain about the environmental controls on organic carbon flux in the coastal zone. Here, we used a field experiment distributed across 28° of latitude, and the entire range of 2 dominant kelp species in the northern hemisphere, to measure decomposition rates of kelp detritus on the seafloor in relation to local environmental factors. Detritus decomposition in both species were strongly related to ocean temperature and initial carbon content, with higher rates of biomass loss at lower latitudes with warmer temperatures. Our experiment showed slow overall decomposition and turnover of kelp detritus and modeling of coastal residence times at our study sites revealed that a significant portion of this production can remain intact long enough to reach deep marine sinks. The results suggest that decomposition of these kelp species could accelerate with ocean warming and that low-latitude kelp forests could experience the greatest increase in remineralization with a 9% to 42% reduced potential for transport to long-term ocean sinks under short-term (RCP4.5) and long-term (RCP8.5) warming scenarios. However, slow decomposition at high latitudes, where kelp abundance is predicted to expand, indicates potential for increasing kelp-carbon sinks in cooler (northern) regions. Our findings reveal an important latitudinal gradient in coastal ecosystem function that provides an improved capacity to predict the implications of ocean warming on carbon cycling. Broad-scale patterns in organic carbon decomposition revealed here can be used to identify hotspots of carbon sequestration potential and resolve relationships between carbon cycling processes and ocean climate at a global scale. Cycling of organic carbon in the ocean has the potential to mitigate or exacerbate global climate change, but how is this influenced by the environment? A field experiment at 35 sites spanning 12 geographic regions allows measurement of decomposition rates and changes in carbon content of kelp detritus in coastal habitats, revealing a strong influence of an ocean-temperature gradient on decomposition.

Teun Schrieks, W. J. Wouter Botzen, W. J. Wouter Botzen et al.

Tawfik Al-Hadhrami, Faisal Saeed, Funminiyi Olajide

Wireless Mesh Networks (WMNs) integrate the advantages of WLANs and mobile Ad Hoc networks, which have become the key techniques of next-generation wireless networks in the context of emergency recovery. Wireless Mesh Networks (WMNs) are multi-hop wireless networks with instant deployment, self-healing, self-organization and self-configuration features. These capabilities make WMNs a promising technology for incident and emergency communication. An incident area network (IAN) needs a reliable and lively routing path during disaster recovery and emergency response operations when infrastructure-based communications and power resources have been destroyed and no routes are available. Power aware routing plays a significant role in WMNs, in order to provide continuous efficient emergency services. The existing power aware routing algorithms used in wireless networks cannot fully fit the characteristics of WMNs, to be used for emergency recovery. This paper proposes a power aware routing algorithm (PARA) for WMNs, which selects optimal paths to send packets, mainly based on the power level of next node along the path. This algorithm was implemented and tested in a proven simulator. The analytic results show that the proposed power node-type aware routing algorithm metric can clearly improve the network performance by reducing the network overheads and maintaining a high delivery ratio with low latency.

SM Shiels, M Bouchard, H Wang et al.

The use of internal intramedullary nails for long bone fracture fixation is a common practice among surgeons. Bacteria naturally attach to these devices, increasing the risk for wound infection, which can result in non- or malunion, additional surgical procedures and extended hospital stays. Intramedullary nail surface properties can be modified to reduce bacterial colonisation and potentially infectious complications. In the current study, a coating combining a non-fouling property with leaching chlorhexidine for orthopaedic implantation was tested. Coating stability and chlorhexidine release were evaluated in vitro. Using a rat model of intramedullary fixation and infection, the effect of the coating on microbial colonisation and fracture healing was evaluated in vivo by quantitative microbiology, micro-computed tomography, plain radiography, three-point bending and/or histology. Low dose systemic cefazolin was administered to increase the similarities to clinical practice, without overshadowing the effect of the anti-infective coating. When introduced into a contaminated wound, the non-fouling chlorhexidine-coated implant reduced the overall bacteria colonisation within the bone and on the implant, reduced the osteolysis and increased the radiographic union, confirming its potential for reducing complications in wounds at high risk of infection. However, when implanted into a sterile wound, non-union increased. Further studies are required to best optimise the anti-microbial effectiveness, while not sacrificing fracture union.

Melike Kahya, Tyler A. Wood, Jacob J. Sosnoff et al.

Introduction: Balance tasks require cognitive resources to ensure postural stability. Pupillometry has been used to quantify cognitive workload of various cognitive tasks, but has not been studied in postural control. The current investigation utilized pupillometry to quantify the cognitive workload of postural control in healthy young adults. We hypothesized that cognitive workload, indexed by pupil size, will increase with challenging postural control conditions including visual occlusion and cognitive dual tasking.Methods: Twenty-one young healthy adults (mean ± standard error of the mean), (age = 23.2 ± 0.49 years; 12 females) were recruited for this study. Participants completed four tasks: (1) standing with eyes open; (2) standing with eyes occluded (3) standing with eyes open while performing an auditory Stroop task; and (4) standing with eyes occluded while performing an auditory Stroop task. Participants wore eye tracking glasses while standing on a force platform. The eye tracking glasses recorded changes in pupil size that in turn were converted into the Index of Cognitive Activity (ICA). ICA values were averaged for each eye and condition. A two-way Analysis of Variance with post-hoc Sidak correction for pairwise comparisons was run to examine the effect of visual occlusion and dual tasking on ICA values as well on Center of Pressure (CoP) sway velocity in anterior–posterior (AP) and medio-lateral (ML) directions. A Pearson’s correlation coefficient was utilized to determine the relationship between ICA values and CoP sway velocity.Results: Significant within-condition effect was observed with visual occlusion for the right eye ICA values (p = 0.008). Right eye ICA increased from eyes open to eyes occluded conditions (p = 0.008). In addition, a significant inverse correlation was observed between right eye ICA values and CoP sway velocity in the ML direction across all the conditions (r = -0.25, p = 0.02).Conclusion: This study demonstrated support for increased cognitive workload, measured by pupillometry, as a result of changes in postural control in healthy young adults. Further research is warranted to investigate the clinical application of pupillometry in balance assessment.

Song Ge, Xing Xi, Gui-fang Guo

Aim: Review the impact of master's-educated nurses on inpatient care in different healthcare systems and specialties. Background: Improved healthcare service quality and efficiency are needed due to a number of factors, including an aging population, advancing medical technology and increasingly complex methods of healthcare delivery. Overcoming these challenges requires nurses with more than a basic nursing education. However, masters training for Chinese nurses is a relatively new development, and, therefore, the cost effectiveness of master's-educated nurses in China and extent to which they contribute to improvements in access to Chinese healthcare services and the quality of those services remains unknown. Method: A systematic review of quantitative studies was conducted using PubMed and the China National Knowledge Infrastructure (CNKI). Studies were included in this review if they met the inclusion criteria. Results: Nine papers met the inclusion criteria and were included in this review. These studies indicated that palliative care, continuity of care, mental health, transition care, post-transplant care and central venous catheter care were improved when patient care was delivered by master's-educated nurses. Conclusion: Developing master's education for nurses may improve the current standard of health care and help meet modern challenges. This topic deserves additional attention at the academic and policy level. This review provides an important reference for Chinese nursing educators and policy makers.

Quentin Philippot, Gaëtan Deslée, Tracy L Adair-Kirk et al.

Free iron in lung can cause the generation of reactive oxygen species, an important factor in chronic obstructive pulmonary disease (COPD) pathogenesis. Iron accumulation has been implicated in oxidative stress in other diseases, such as Alzheimer's and Parkinson's diseases, but little is known about iron accumulation in COPD. We sought to determine if iron content and the expression of iron transport and/or storage genes in lung differ between controls and COPD subjects, and whether changes in these correlate with airway obstruction. Explanted lung tissue was obtained from transplant donors, GOLD 2-3 COPD subjects, and GOLD 4 lung transplant recipients, and bronchoalveolar lavage (BAL) cells were obtained from non-smokers, healthy smokers, and GOLD 1-3 COPD subjects. Iron-positive cells were quantified histologically, and the expression of iron uptake (transferrin and transferrin receptor), storage (ferritin) and export (ferroportin) genes was examined by real-time RT-PCR assay. Percentage of iron-positive cells and expression levels of iron metabolism genes were examined for correlations with airflow limitation indices (forced expiratory volume in the first second (FEV1) and the ratio between FEV1 and forced vital capacity (FEV1/FVC)). The alveolar macrophage was identified as the predominant iron-positive cell type in lung tissues. Furthermore, the quantity of iron deposit and the percentage of iron positive macrophages were increased with COPD and emphysema severity. The mRNA expression of iron uptake and storage genes transferrin and ferritin were significantly increased in GOLD 4 COPD lungs compared to donors (6.9 and 3.22 fold increase, respectively). In BAL cells, the mRNA expression of transferrin, transferrin receptor and ferritin correlated with airway obstruction. These results support activation of an iron sequestration mechanism by alveolar macrophages in COPD, which we postulate is a protective mechanism against iron induced oxidative stress.

Simone Cesaro, Francesca Nesi, Gloria Tridello et al.

<h4>Purpose</h4>To assess the non-inferiority of pegfilgrastim versus filgrastim in speeding the recovery of polymorphonuclear cells (PMN) in pediatric patients who underwent autologous peripheral blood stem cell transplant (PBSCT).<h4>Methods</h4>The sample size of this randomized, multicenter, phase III study, was calculated assuming that a single dose of pegfilgrastim of 100 ug/kg was not inferior to 9 doses of filgrastim of 5 ug/kg/day. Randomization was performed by a computer-generated list and stored by sequentially numbered sealed envelopes.<h4>Results</h4>Sixty-one patients, with a median age of 11.5 years, were recruited: 29 in the filgrastim arm and 32 in the pegfilgrastim arm. Twenty percent were affected by lymphoma/leukaemia and eighty percent by solid tumors. The mean time to PMN engraftment was 10.48 days (standard deviation [SD] 1.57) and 10.44 days (SD 2.44) in the filgrastim and pegfilgrastim arms, respectively. Having fixed a non-inferiority margin Delta of 3, the primary endpoint of non-inferiority was reached. No differences were observed for other secondary endpoints: platelet engraftment, mean time to platelet recovery (28 days vs. 33 days), fever of unknown origin (79% vs. 78%), proven infection (34% vs. 28%), mucositis (76% vs. 59%). After a median follow-up of 2.3 years (95% C.I.: 1.5, 3.3), 20 deaths were observed due to disease progression.<h4>Conclusions</h4>We conclude that pegfilgrastim was not inferior to daily filgrastim in pediatric patients who underwent PBSCT. EU CLINICAL TRIAL REGISTER NUMBER: 2007-001430-14.

John Peckenham, David Hart, Sean Smith et al.

Guy C J Abell, Stan S Robert, Dion M F Frampton et al.

Advances in microbial ecology research are more often than not limited by the capabilities of available methodologies. Aerobic autotrophic nitrification is one of the most important and well studied microbiological processes in terrestrial and aquatic ecosystems. We have developed and validated a microbial diagnostic microarray based on the ammonia-monooxygenase subunit A (amoA) gene, enabling the in-depth analysis of the community structure of bacterial and archaeal ammonia oxidisers. The amoA microarray has been successfully applied to analyse nitrifier diversity in marine, estuarine, soil and wastewater treatment plant environments. The microarray has moderate costs for labour and consumables and enables the analysis of hundreds of environmental DNA or RNA samples per week per person. The array has been thoroughly validated with a range of individual and complex targets (amoA clones and environmental samples, respectively), combined with parallel analysis using traditional sequencing methods. The moderate cost and high throughput of the microarray makes it possible to adequately address broader questions of the ecology of microbial ammonia oxidation requiring high sample numbers and high resolution of the community composition.