Clock Method Research Articles

NavIC receiver clock offsets estimation with common view master clock method

The current manuscript proposes a new methodology for receiver clock offset estimation in IRNSS (Indian Regional Navigation Satellite System) which is also known as NavIC (Navigation Indian Constellation). This new methodology has been designed by clubbing the master clock concept with the traditional common view time transfer method and therefore it has been named as Common View Master Clock Method (CVMCM). The proposed methodology is intended to share the reference time uniformly and precisely across all the receiver clocks of IRNSS. The IRNSS receivers equipped at IRIMS (IRNSS Range and Integrity Monitoring Stations) acquire IRNSS satellite signals and generate code and carrier phase measurements on L5 and S frequencies. For ease of convenience, this range measurements and broadcast navigation messages are converted to standard RINEX (Receiver Independent Exchange) format in the form of RINEX observation files and RINEX navigation files respectively. As IRNWT1 (IRNSS Network Time Facility Bangalore) has been directly fetched to IRIMS Bangalore we have chosen IRIMS Bangalore as the master (reference) station. This is followed by time offset estimation of all IRIMS with respect to IRIMS Bangalore using the CVMCM method. This proposed methodology reduces all the error sources in IRNSS signals and produces very accurate time offsets results for all IRIMS. This helps in maintaining IRNSS reference time very precisely across all IRIMS with a proper time steering, thereby revamping the process of time synchronization in NavIC. Analyses were performed which establishes the stability and credibility of our results. In the process, it also corrects almost all the error sources in NavIC signals.

Phylogeny, Macroevolutionary Trends and Historical Biogeography of Sloths: Insights From a Bayesian Morphological Clock Analysis.

Sloths, like other xenarthrans, are an extremely interesting group of mammals that, after a long history of evolution and diversification in South America, became established on islands in the Caribbean and later reached North America during the Great American Biotic Interchange. In all three regions, they were part of the impressive Pleistocene megafauna. Most taxa became extinct and only two small, distantly related tree-dwelling genera survived. Here, we incorporate several recently described genera of sloths into an assembled morphological data supermatrix and apply Bayesian inference, using phylogenetic and morphological clock methods, to 64 sloth genera. Thus, we investigate the evolution of the group in terms of the timing of divergence of different lineages and their diversity, morphological disparity and biogeographical history. The phylogeny obtained supports the existence of the commonly recognized clades for the group. Our results provide divergence time estimates for the major clades within Folivora that could not be dated with molecular methods. Lineage diversity shows an early increase, reaching a peak in the Early Miocene followed by a major drop at the end of the Santacrucian (Early Miocene). A second peak in the Late Miocene was also followed by a major drop at the end of the Huayquerian (Late Miocene). Both events show differential impact at the family level. After that, a slight Plio-Pleistocene decline was observed before the marked drop with the extinction at the end of the Pleistocene. Phenotypic evolutionary rates were high during the early history of the clade, mainly associated with Mylodontidae, but rapidly decreased to lower values around 25 Ma, whereas Megalonychidae had lower rates at the beginning followed by a steady increase, peaking during the Late Miocene and the Pliocene. Morphological disparity showed a similar trend, with an early increase, followed by a slowly increasing phase through the Late Oligocene and Early Miocene, and ending with another increase beginning at the middle of the Miocene. Biogeographic analysis showed southern South America as the most probable area of origin of the clade and the main region in which the early diversification events took place. Both Megatheriinae and Nothrotheriinae basal nodes were strongly correlated with Andean uplift events, whereas the early history of Mylodontidae is closely associated with southern South America and also shows an early occupation of the northern regions. Within Megalonychidae, our results show Choloepus as a descendant of an island dispersing ancestor and a probable re-ingression to South America by a clade that originated in Central or North America.

Popliteal neurovascular bundle is safe during inside-out repair of medial meniscus without a safety incision.

There is a theoretical risk of injury to neurovascular structures during inside-out meniscal repair without a safety incision, although there are limited studies assessing this risk. This simulation study on archival MRI films was performed to assess the risk for the popliteal neurovascular bundle and the peroneal nerve during passage of needles for inside-out meniscus repair without a "safety incision", thereby defining a "safe zone" of the menisci that can be safely repaired using this technique. Archival MRI scans (n = 50) were retrieved and axial sections through the menisci were used for simulation. The needle passage was simulated for different points on the posterior horn and body of lateral and medial menisci at "half-hour" intervals using clock method (15° intervals) with three different portals and two different needle cannulas, resulting in six different scenarios of needle passage for each point on the meniscus. The distance of the needle in each scenario was measured from popliteal vessels (n = 50) and peroneal nerve (n = 10). The value "mean-3SD" was calculated for positive means and "Mean + 3SD" was calculated if the mean was negative. An additional 2mm was defined as "safe distance". Thus, simulation models in which the mean - 3SD was less than 2mm (or mean + 3SD was greater than - 2mm for negative means) were labelled as "unsafe". Needle passage through medial meniscus at and medial to 1 o'clock position for a right knee (or 11 o'clock position for a left knee) was safe, irrespective of the portal and needle type. For the lateral meniscus, only the equatorial region was found to be safe with this method. The popliteal neurovascular bundle is safe during the inside-out medial meniscal repair without a safety incision. For the terminal-most part of the posterior horn, the AM portal and the straight cannula should be avoided. However, this method without safety incision cannot be recommended for lateral meniscus because of the risk to the popliteal vessels and the peroneal nerve. Instead, the inside-out method with a safety incision, or an all-inside method should be used for lateral meniscus. III.

Perinatally acquired HIV infection accelerates epigenetic aging in South African adolescents.

Recent studies demonstrate that infection with the HIV-1 is associated with accelerated aging effects in adults according to a highly accurate epigenetic biomarker of aging known as epigenetic clock. However, it is not yet known whether epigenetic age acceleration occurs as early as adolescence in perinatally HIV-infected (PHIV+) youth. Observational study of PHIV and HIV-uninfected adolescents enrolled in the Cape Town Adolescent Antiretroviral Cohort Study. The Illumina EPIC array was used to generate blood DNA methylation data from 204 PHIV and 44 age-matched, uninfected (HIV-) adolescents aged 9-12 years old. The epigenetic clock software and method was used to estimate two measures of epigenetic age acceleration. Each participant completed a comprehensive neuropsychological test battery upon enrollment to Cape Town Adolescent Antiretroviral Cohort. HIV is associated with biologically older blood in PHIV+ adolescents according to both measures of epigenetic age acceleration. One of the measures, extrinsic epigenetic age acceleration, is negatively correlated with measures of cognitive functioning (executive functioning, working memory, processing speed). Overall, our results indicate that epigenetic age acceleration in blood can be observed in PHIV+ adolescents and that these epigenetic changes accompany poorer cognitive functioning.

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Inside view

Femtosecond and Attosecond Electron-Transfer Dynamics in PCPDTBT:PCBM Bulk Heterojunctions

Charge separation efficiency is a crucial parameter for photovoltaic devices—polymers consisting of alternating electron-rich and electron-deficient parts can achieve high such efficiencies, for instance, together with a fullerene electron acceptor. This offers a viable path toward solar cells with organic bulk heterojunctions. Here, we measured the charge-transfer times in the femtosecond and attosecond regimes via the decay of sulfur 1s X-ray core-excited states (with the core-hole clock method) in blends of a low-band gap polymer {PCPDTBT [poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b′]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)]]} consisting of a cyclopentadithiophene electron-rich part and a benzothiadiazole electron-deficient part. The constituting parts of the bulk heterojunction were varied by adding the fullerene derivative PCBM ([6,6]-phenyl-C61-butyric acid methyl ester) (weight ratio of polymer/PCBM as 1:0, 1:1, 1:2, and 1:3). For low-energy excitations, the charge-transfer time ...

The fossil record and the origin of ticks revisited.

The fossil record of ticks has been classically used to discern the probable vicariance events of these arthropods, and to date the split moments of the different lineages. Although new techniques based on molecular clock methods are already available, tick fossil record still stands as a valuable source of information if correctly interpreted. Here we report about a male specimen of Ornithodoros (Alectorobius) sp. found in Dominican amber of about 25millions years, illustrating its main morphological features. We also discuss the findings in a recent paper, which may contain unreliable interpretations on some fossil ticks. We support previous data on the presence of Argasidae in Miocene Dominican amber, and provide comments on the presence of ticks in Burmese amber. We further elaborate on the spread of ticks in the light of the record and description of a new family found in Cretaceous amber.

Clock and trigger distribution for CBM-TOF quality evaluation of RPC super module detector assemblies

RPC Super module (SM) detector assemblies are used for charged hadron identification in the Time-of-Flight (TOF) spectrometer at the Compressed Baryonic Matter (CBM) experiment. Each SM contains several multi-gap Resistive Plate Chambers (MRPCs) and provides up to 320 electronic channels in total for high-precision time measurements. Time resolution of the Time-to-Digital Converter (TDC) is required to be better than 20 ps. During mass production, the quality of each SM needs to be evaluated. In order to meet the requirements, the system clock signal as well as the trigger signal should be distributed precisely and synchronously to all electronics modules within the evaluation readout system. In this paper, a hierarchical clock and trigger distribution method is proposed for the quality evaluation of CBM-TOF SM detectors. In a first stage, the master clock and trigger module (CTM) allocated in a 6U PXI chassis distributes the clock and trigger signals to the slave CTM in the same chassis. In a second stage, the slave CTM transmits the clock and trigger signals to the TDC readout module (TRM) through one optical link. In a third stage, the TRM distributes the clock and trigger signals synchronously to 10 individual TDC boards. Laboratory test results show that the clock jitter at the third stage is less than 4 ps (RMS) and the trigger transmission latency from the master CTM to the TDC is about 272 ns with 11 ps (RMS) jitter. The overall performance complies well with the required specifications.

An Anatomical Study of Nerves at Risk During Minimally Invasive Hallux Valgus Surgery.

The growing popularity of minimally invasive surgical (MIS) procedures makes it necessary that new anatomical references arise, to aid in tridimensional orientation and localization of structures that are not directly visible to the surgeon. This is especially critical for structures at risk like nerves or blood vessels. Optimization of the handling of cadaveric material and the combination of multiple techniques compensate for the limited availability of adequate specimens. The described protocol combines anatomical plane-by-plane dissection and sectional anatomy of fresh-frozen specimens to help localize relevant structures, such as nerves, arteries, veins and to correctly position the portals during MIS procedures. Depiction of these structures in anatomy textbooks can differ from what is encountered in the surgical field; and for this reason, new anatomical studies with a surgical orientation are needed. However, this is a complex, time-consuming technique requiring specific training. The anatomical references described with the so-called 'clock method' provide the surgeon with an easy and reproducible system to locate the path of the nerves at risk in Hallux Valgus MIS procedures. This model can be extrapolated to many other minimally invasive surgical procedures.

1-bit and 2-bit Comparator Designs and Analyses for Quantum-Dot Cellular Automata

In computerized PCs number of arithmetic operations, the comparator is the vital equipment unit, composed of CMOS innovation. Another procedure named as Quantum Cellular Automata (QCA) will supplant the CMOS outlines, having leverage concerning zone, control utilization, and latency. The primary QCA circuits planned with the inverter and majority voter entryways. In this paper, we utilize the clocking method 180º out of phase clock hybrid to outline the 1-bit comparator and contrast and the current outcomes. The new proposed wire crossing plan lessens the quantity of cells required to configuration, power and area necessities. Besides, we planned 2-bit comparator with 11 number of majority voters, 2 number of crossovers with 0.38 um^2 area, 203 number of cells. The designed 1-bit comparator contrast and the past outcomes where cells, region, defer demonstrates 53.57%, 50%, 33.32% improvement respectively.

New Method for Simultaneous Determination of Ascorbic and Acetylsalicylic Acids in Effervescent Tablets

The determination of the real concentration in different pharmaceutical drugs represents a very important goal of the pharmaceutical industry. The main aim of the study was to set up a simple, cheap and rapid method in order to determine both ascorbic and acetylsalicylic acid content of effervescent tablets that could be found on the pharmaceutical market, without preliminary separation or extraction. For this purpose, a very simple and reliable clock method based on two Landolt-type systems of reactions, based on potentiometric techniques, has been developed. The method has been tested on different effervescent tablets which contain ascorbic acid and acetylsalicylic acid in different mixture ratio.

Phylogeography of the Central American lancehead Bothrops asper (SERPENTES: VIPERIDAE).

The uplift and final connection of the Central American land bridge is considered the major event that allowed biotic exchange between vertebrate lineages of northern and southern origin in the New World. However, given the complex tectonics that shaped Middle America, there is still substantial controversy over details of this geographical reconnection, and its role in determining biogeographic patterns in the region. Here, we examine the phylogeography of Bothrops asper, a widely distributed pitviper in Middle America and northwestern South America, in an attempt to evaluate how the final Isthmian uplift and other biogeographical boundaries in the region influenced genealogical lineage divergence in this species. We examined sequence data from two mitochondrial genes (MT-CYB and MT-ND4) from 111 specimens of B. asper, representing 70 localities throughout the species’ distribution. We reconstructed phylogeographic patterns using maximum likelihood and Bayesian methods and estimated divergence time using the Bayesian relaxed clock method. Within the nominal species, an early split led to two divergent lineages of B. asper: one includes five phylogroups distributed in Caribbean Middle America and southwestern Ecuador, and the other comprises five other groups scattered in the Pacific slope of Isthmian Central America and northwestern South America. Our results provide evidence of a complex transition that involves at least two dispersal events into Middle America during the final closure of the Isthmus.

The Efficacy of Consensus Tree Methods for Summarizing Phylogenetic Relationships from a Posterior Sample of Trees Estimated from Morphological Data.

Consensus trees are required to summarize trees obtained through MCMC sampling of a posterior distribution, providing an overview of the distribution of estimated parameters such as topology, branch lengths, and divergence times. Numerous consensus tree construction methods are available, each presenting a different interpretation of the tree sample. The rise of morphological clock and sampled-ancestor methods of divergence time estimation, in which times and topology are coestimated, has increased the popularity of the maximum clade credibility (MCC) consensus tree method. The MCC method assumes that the sampled, fully resolved topology with the highest clade credibility is an adequate summary of the most probable clades, with parameter estimates from compatible sampled trees used to obtain the marginal distributions of parameters such as clade ages and branch lengths. Using both simulated and empirical data, we demonstrate that MCC trees, and trees constructed using the similar maximum a posteriori (MAP) method, often include poorly supported and incorrect clades when summarizing diffuse posterior samples of trees. We demonstrate that the paucity of information in morphological data sets contributes to the inability of MCC and MAP trees to accurately summarise of the posterior distribution. Conversely, majority-rule consensus (MRC) trees represent a lower proportion of incorrect nodes when summarizing the same posterior samples of trees. Thus, we advocate the use of MRC trees, in place of MCC or MAP trees, in attempts to summarize the results of Bayesian phylogenetic analyses of morphological data.

Comment: Characterization of Two Historic Smallpox Specimens from a Czech Museum.

The complete genome sequences of two strains of variola virus (VARV) sampled from human smallpox specimens present in the Czech National Museum, Prague, were recently determined, with one of the sequences estimated to date to the mid-19th century. Using molecular clock methods, the authors of this study go on to infer that the currently available strains of VARV share an older common ancestor, at around 1350 AD, than some recent estimates based on other archival human samples. Herein, we show that the two Czech strains exhibit anomalous branch lengths given their proposed age, and by assuming a constant rate of evolutionary change across the rest of the VARV phylogeny estimate that their true age in fact lies between 1918 and 1937. We therefore suggest that the age of the common ancestor of currently available VARV genomes most likely dates to late 16th and early 17th centuries and not ~1350 AD.

Phylogenetic and divergence time analysis of the Chelonoidis chilensis complex (Testudines: Testudinidae)

We present a phylogenetic and divergence time analysis of the Chelonoidis chilensis complex (the southernmost tortoises of South America) within crown Testudinidae. We compiled a dataset of 1118 bp cytochrome b (cyt b) sequences derived from 111 individuals sampled across the known geographic range of the species, and performed a phylogenetic analysis employing Maximum Parsimony, Maximum Likelihood and Bayesian Inference methods. The resulting trees showed similar topologies and support values. The C. chilensis complex was always recovered as a monophyletic group composed by two major clades (i.e. haplogroups). The biogeographic distribution of one of these clades overlaps with the Dry Chaco eco–region, while the biogeographic distribution of the other overlaps with the Monte eco–region. In order to date the origin and diversification time of these two clades, we employed a previously published two-step molecular clock method. In the first step we dated the time of origin of C. chilensis as a clade within the Testudinidae family using new and previously published sequences, extinct testudinid taxa for age calibration and the Fossilized Birth-Death (FBD) model. In the second step we dated the divergence between the haplogroups of C. chilensis based on the time of origin estimated in the first step and a coalescent evolution model. Our results suggest that divergence between Dry Chaco and Monte tortoises may have occurred about 2.47 million of years ago. We interpret these results in the light of the environmental and geological changes that occurred during the late Pliocene to Middle Pleistocene of South America.

P 79 Physiological assessment of the sense of agency in psychogenic movement disorders

Psychogenic movement disorders (PMD) are conditions characterized by the occurrence of unwanted motoric symptoms in which a somatic reason cannot be found. As patients suffering from PMD experience their pathological movements as non-voluntary, it is hypothesized that those patients have an altered sense of agency (SoA). SoA is defined as the feeling of controlling ones own actions and through them controlling events in the external world ( Haggard and Tsakiris, 2009 ). SoA can be assessed by measuring the intentional binding (IB) effect. This is the perceived convergence of the time between a voluntary action and an auditory stimulus provoked by that action. To test the hypothesis we used a setting based on the Libet clock method ( Libet et al., 1983 ) introduced by Haggard et al. (2002) . To date, in total 59 subjects were enrolled: 5 subjects with the diagnosis of PMD, 35 with a somatic movement disorder (SMD) and 19 healthy controls. SMD patient group consisted of patients with Parkinsons disease ( n = 18), neuropathies ( n = 10), stroke ( n = 7) and multiple sclerosis ( n = 1). IB values were 0.18 ± 0.06 s for PMD, 0.16 ± 0.09 s for SMD and 0.12 ± 0.09 s for healthy controls (mean ± SD). So far, there were no significant differences in IB between PMD, SMD and healthy controls in the examined study group (PMD vs. healthy controls, p = 0.1. Two-sample t -tests). Patients with a motor disorder (both SMD and PMD) tended to have higher IB values compared to healthy controls (SMD vs. healthy controls, p = 0.08). IB values did not differ between SMD and PMD patients (PMD vs. SMD, p = 0.7). Our findings are in line with evidence derived from small study groups that binding processes are altered in PMD patients compared to healthy controls ( Kranick et al., 2013 ). However, since PMD patients did not differ from SMD patients, a specific binding problem is unlikely to represent the pathophysiological mechanism in psychogenic movement disorders.

Design of Electronic Clock based on STM32

This paper describes the design method of electronic clock based on STM32. The hardware circuit is designed, which uses the built-in RTC module of the STM32, and the backup battery is used to supply power. When first programming, the current date and time is wrote, after that the RTC module will automatically count. It also can be used to set the alarm time. Software programming can read the current time and conversion it, then it will be displayed on the LCD screen. The test results show that the design has the advantages of accurate timing, high reliability and long service life.

Statistical analysis and quality control for GPS fractional cycle bias and integer recovery clock estimation with raw and combined observation models

With the development of Ambiguity Resolution for Precise Point Positioning (PPP-AR) over the past years, there are three representative PPP-AR methods up to now: Fractional Cycle Bias (FCB) method, Integer Recovery Clock (IRC) method and Decoupled Satellite Clock (DSC) method. In all these methods, satellite products are generated from a global or regional reference network and then broadcast to users for ambiguity fixing. Positioning accuracy with short-time observations can be significantly improved after ambiguities are correctly fixed; nevertheless, high-accuracy satellite products are the prerequisite of reliable ambiguity resolution. Therefore, quality control for PPP-AR at network end is of great significance. In this paper, FCB and IRC estimation methods based on Ionosphere-Free PPP (IF-PPP) and Uncombined PPP (U-PPP) are investigated. In addition, quality control strategy for FCB and IRC estimation is proposed. Data sets from International GNSS Service (IGS) network and CORSnet-NSW in Australia are used to validate and demonstrate the performance of the proposed method. The results indicate that reliable PPP-AR can be achieved with the estimated FCB and IRC products, similar PPP-AR performance is revealed with IF-PPP and U-PPP. After ambiguities are successfully fixed, positioning accuracy in the east, north and up directions can reach 0.7, 0.9 and 3.1cm, respectively, which is a considerable improvement as compared with ambiguity-float PPP solution. Moreover, the FCB method slightly outperforms the IRC method due to the better reliability of FCB estimation. In addition, accurate ionospheric delay can be derived from a regional reference network to enhance the model strength of U-PPP, thus the Time-To-First-Fix (TTFF) can be further shortened. Even instantaneous ambiguity fixing is achievable and the positioning accuracy can reach 0.1, 1.2 and 0.4cm.

The ranking of fungi: a tribute to David L. Hawksworth on his 70th birthday

The history of assigning ranks to fungi, as well as the relative importance of using divergence time estimates is reviewed. The paper pays tribute to the major mycological players, and especially to David Hawksworth on his 70th birthday and his contribution to fungal ranking in Systema Ascomycetum from 1982 to 1998. Following the conclusion of the latter series, the ranking continued with the Outlines of Ascomycota in 2007 and 2010 and more recently with specific classes in 'Towards an outline of Sordariomycetes' and 'Families of Dothideomycetes'. Earlier classifications based on phenotype were certainly more subjective; however, remarkably many of these old arrangements have stood the test of time. More recently, phylogenetic analyses have provided evidence towards a natural classification, resulting in significant changes in many lineages. The classification arrangements however, are still subjective and dependent on the taxa analysed, resulting in different taxonomic interpretations and schemes, particularly when it comes to ranking. Thus, what have been considered as genera by some, have been introduced as families by others. More recently, estimation of divergence times using molecular clock methods have been used as objective evidence for higher ranking of taxa. A divergence period (i.e. 200-300 MYA) can be used as a criterion to infer when a group of related taxa evolved and what rank they should be given. We compiled data on divergence times for various higher ranking taxa in the Kingdom Fungi. The kingdom evolved 1000-1600 MYA (Stenian-Calymmian), while the presently accepted phyla evolved between 358 and 541 MYA (Devonian-Cambrian). Divergence times for subphyla are generally between 358 and 485 MYA (Devonian-Ordovician), those of classes 145-358 MYA (Jurassic-Carboniferous), subclasses 66-358 MYA (Cretaceous-Carboniferous), orders 23-252 MYA (Paleogene-Triassic), families 2.8-145 MYA (Neogene-Cretaceous), and genera 2.8-66 MYA (Neogene-Paleogene). Thus, there are wide discrepancies in the times different taxa diverged. We provide an overview over Ascomycota, showing how application of temporal banding could affect the recognition of higher taxa at certain rank levels. We then use Sordariomycetes as an example where we use divergence times to provide additional evidence to stabilize ranking of taxa below class level. We propose a series of evolutionary periods that could be used as a guide to determine the various higher ranks of fungi: phyla[550 MYA, subphyla 400-550 MYA; classes 300-400 MYA; subclasses 250-300 MYA, orders 150-250 MYA, and families 50-150 MYA. It is proposed that classification schemes and ranking of taxa should, where possible, incorporate a polyphasic approach including phylogeny, phenotype, and estimate of divergence times.

Ranking higher taxa using divergence times: a case study in Dothideomycetes

The current classification system for the recognition of taxonomic ranks among fungi, especially at high-ranking level, is subjective. With the development of molecular approaches and the availability of fossil calibration data, the use of divergence times as a universally standardized criterion for ranking taxa has now become possible. We can therefore date the origin of Ascomycota lineages by using molecular clock methods and establish the divergence times for the orders and families of Dothideomycetes. We chose Dothideomycetes, the largest class of the phylum Ascomycota, which contains 32 orders, to establish ages at which points orders have split; and Pleosporales, the largest order of Dothideomycetes with 55 families, to establish family divergence times. We have assembled a multi-gene data set (LSU, SSU, TEF1 and RPB2) from 391 taxa representing most family groups of Dothideomycetes and utilized fossil calibration points solely from within the ascomycetes and a Bayesian approach to establish divergence times of Dothideomycetes lineages. Two separated datasets were analysed: (i) 272 taxa representing 32 orders of Dothideomycetes were included for the order level analysis, and (ii) 191 taxa representing 55 families of Pleosporales were included for the family level analysis. Our results indicate that divergence times (crown age) for most orders (20 out of 32, or 63%) are between 100 and 220 Mya, while divergence times for most families (39 out of 55, or 71%) are between 20 and 100 Mya. We believe that divergence times can provide additional evidence to support establishment of higher level taxa, such as families, orders and classes. Taking advantage of this added approach, we can strive towards establishing a standardized taxonomic system both within and outside Fungi. In this study we found that molecular dating coupled with phylogenetic inferences provides no support for the taxonomic status of two currently recognized orders, namely Bezerromycetales and Wiesneriomycetales and these are treated as synonyms of Tubeufiales while Asterotexiales is treated as a synonym of Asterinales. In addition, we provide an updated phylogenetic assessment of Dothideomycetes previously published as the Families of Dothideomycetes in 2013 with a further ten orders and 35 families.