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Background: We aimed to investigate whether pre-therapeutic radiomic features based on magnetic resonance imaging (MRI) can predict the clinical response to neoadjuvant chemotherapy (NACT) in patients with locally advanced cervical cancer (LACC). Methods: A total of 275 patients with LACC receiving NACT were enrolled in this study from eight hospitals, and allocated to primary and independent validation cohorts (2:1 ratio). Three radiomic feature sets were extracted from the intratumoural region of T1-weighted images, intratumoural region of T2-weighted images, and peritumoural region of T2-weighted images before NACT for each patient. With a feature selection strategy, three single sequence radiomic models were constructed, and three additional combined models were constructed by combining the features of different regions or sequences. The performance of all models was assessed using receiver operating characteristic curve. Findings: The combined model of the intratumoural zone of T1-weighted images, intratumoural zone of T2-weighted images ,and peritumoural zone of T2-weighted images achieved an AUC of 0.998 in primary cohort and 0.999 in validation cohort, which was significantly better (p

Purpose MR fingerprinting (MRF) sequences permit efficient T1 and T2 estimation in cranial and extracranial regions, but these areas may include substantial fat signals that bias T1 and T2 estimates. MRI fat signal fraction estimation is also a topic of active research in itself, but may be complicated by B0 heterogeneity and blurring during spiral k-space acquisitions, which are commonly used for MRF. An MRF method is proposed that separates fat and water signals, estimates water T1 and T2, and accounts for B0 effects with spiral blurring correction, in a single sequence. Theory and methods A k-space-based fat-water separation method is further extended to unbalanced steady-state free precession MRF with swept echo time. Repeated application of this k-space fat-water separation to demodulated forms of the measured data allows a B0 map and correction to be approximated. The method is compared with MRF without fat separation across a broad range of fat signal fractions (FSFs), water T1s and T2s, and under heterogeneous static fields in simulations, phantoms, and in vivo. Results The proposed method's FSF estimates had a concordance correlation coefficient of 0.990 with conventional measurements, and reduced biases in the T1 and T2 estimates due to fat signal relative to other MRF sequences by several hundred ms. The B0 correction improved the FSF, T1, and T2 estimation compared to those estimates without correction. Conclusion The proposed method improves MRF water T1 and T2 estimation in the presence of fat and provides accurate FSF estimation with inline B0 correction.

We highlight new evolutionary insights enabled by recent genome-wide studies on protein-protein interaction (PPI) networks ('interactomes'). While most PPIs are mediated by a single sequence region promoting or inhibiting interactions, many PPIs are mediated by multiple sequence regions acting cooperatively. Most PPIs perform important functions maintained by negative selection: we estimate that less than ∼10% of the human interactome is effectively neutral upon perturbation (i.e. 'junk' PPIs), and the rest are deleterious upon perturbation; interfacial sites evolve more slowly than other sites; many conserved PPIs show signatures of co-evolution at the interface; PPIs evolve more slowly than protein sequence. At the same time, many PPIs undergo rewiring during evolution for lineage-specific adaptation. Finally, chaperone-protein and host-pathogen interactomes are governed by distinct evolutionary principles.

In this paper, by incorporating a multi-step scheme into the doubly stabilized bundle method (DSBM) recently developed by Oliveira and Solodov (2016), we propose a multi-step doubly stabilized bundle method (MDSBM) for solving nonsmooth convex optimization problems. In contrast to a single sequence generated by DSBM, the MDSBM generates three related iteration sequences. One is used to build the cutting-planes model of the objective function, another is served as the stability centers, and the third is the sequence of solutions to our new doubly stabilized subproblems. In addition, we present a new descent test criterion, aiming to take advantage of the multi-step scheme. We establish global convergence of the proposed method, and finally present some promising numerical results.

A new 1 MV NEC pelletron AMS system at ANSTO is presented. The spectrometer comprises large radius magnets for actinide measurements. A novel feature of the system is fast switching between isotopes both at low and high energy sections allowing measurements of up to 8 isotopes within a single sequence. Technical details and layout of the spectrometer is presented. Performance data for 14C, 10Be, 26Al and actinides demonstrate the system is ready for routine AMS measurements.

Periodic-Frequent Pattern Mining (PFPM) is an emerging problem, which consists of identifying frequent patterns that periodically occur over time in a sequence of events. Though PFPM is useful in many domains, traditional algorithms have two important limitations. First, they are not designed to find rare patterns. But discovering rare patterns is useful in many domains (e.g. to study rare diseases). Second, traditional PFPM algorithms are generally designed to find patterns in a single sequence, but identifying periodic patterns that are common to a set of sequences is often desirable (e.g. to find patterns common to several hospital patients or customers). To address these limitations, this paper proposes to discover a novel type of patterns in multiple sequences called Rare Correlated Periodic Patterns. Properties of the problem are studied, and an efficient algorithm named MRCPPS (Mining Rare Correlated Periodic Patterns common to multiple Sequences) is presented to efficiently find these patterns. It relies on a novel RCPPS-list structure to avoid repeatedly scanning the database. Experiments have been done on several real datasets, and it was observed that the proposed MRCPPS algorithm can efficiently discover all rare correlated periodic patterns common to multiple sequences, and filter many non rare and correlated patterns.

Because a vast majority (99%) of microbes in a given community is likely to be non-cultivable, metagenomics has gradually entered the mainstream of microbial research methods. With the development of high-throughput sequencing techniques, an increasing number of sequencing read data sets of metagenomes from various microbial communities have become available. For these data sets, metagenomic analysis based on mapping reads to microbial genomes has been hampered by the limited number of microbial genomes that are available. Further, this type of analysis is computationally intensive. Thus alignment-free methods, which characterize the sequencing reads with a genomic signature instead of with genomic alignments, can be applied. However, the main requirement of these alignment-free methods is a stable genomic signature that performs reliably. Here, we propose a novel genomic signature of microbial genomes called the intrinsic correlation of oligonucleotides (ICOs). This signature represents the quantification of an intrinsic relationship between any two oligonucleotides. We analyzed microbial genomes at different taxonomic levels using ICO profiles and confirmed the wide availability of useful ICOs. We used intra-genomic and inter-genomic distances and relational grades to evaluate the performance of ICOs as a genomic signature. The results of these experiments showed that ICOs can characterize microbial genomes well, and ICOs were better at distinguishing species than tetranucleotide composition, not only in terms of whole genomes but also in terms of sequence fragments. In addition, we evaluated the performance of a hybrid feature that combined ICOs and tetranucleotide composition. The experimental results showed that the hybrid feature performed better than ICOs or tetranucleotide composition alone. ICOs can characterize microbial genomes successfully and are capable of distinguishing organisms at different taxonomic levels. ICOs perform better than tetranucleotide composition in characterizing microbial genomes. The hybrid feature that used a combination of the two kinds of sequence features had advantages over a single sequence feature.

An element of finite order in the Riordan group over the real field must have order 1 or 2. If we extend all the entries to be complex numbers then it may have any finite order. In the present paper, we investigate the elements of finite order of the Riordan group over the complex field. This notion leads us to define an element of pseudo order k ⩾ 2 and k-pseudo involution, respectively. It turns out that the inverse of a k-pseudo involution only differs from it in signs. We clarify some relationship between the elements of pseudo order k and k-pseudo involutions. In particular, k-pseudo involutions for k ≡ 0 ( mod 4 ) are characterized by a single sequence. The subgroups of the Riordan group formed by the elements having pseudo order of a prime power p r are also introduced.

Clin Microbiol Infect 2012; 18: E369E372 Abstract Recently, the first outbreak of clonally related VIM-2 metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa in a Dutch tertiary-care centre was described. Subsequently, a nationwide surveillance study was performed in 2010-2011, which identified the presence of VIM-2 MBL-producing P. aeruginosa in 11 different hospitals. Genotyping by multiple-locus variable-number tandem-repeat analysis (MLVA) showed that the majority of the 82 MBL-producing isolates found belonged to a single MLVA type (n = 70, 85%), identified as ST111 by multilocus sequence typing (MLST). As MBL-producing isolates cause serious infections that are difficult to treat, the presence of clonally related isolates in various hospitals throughout the Netherlands is of nationwide concern.

A peach-to-nectarine mutant ‘Yuval’, a white, melting-flesh, cling-stone fruit was compared over three seasons with its peach progenitor ‘Oded’, an early season cultivar, to study ripening and storage characteristics. Twenty-four genome-spanning single sequence repeats markers showed the identity of the peach with its nectarine mutant at the DNA level. There was no difference in cell size at harvest between the ‘Oded’ peach and ‘Yuval’ nectarine, although ‘Oded’ peach was 24% larger by weight than ‘Yuval’. The ‘Oded’ peaches were also less acidic, and had less soluble solids than the ‘Yuval’ nectarine at harvest. Fruit were stored at two temperatures, 5 ◦ C and 0 ◦ C. Softening was faster in the fruit of both cultivars stored at 5 ◦C than 0 ◦C. At 3 d ripening at 20 ◦C after cold storage, there was more expressible juice at 5 ◦C than 0 ◦ C in the fruit of both cultivars. ‘Oded’ peaches developed internal browning and woolliness at 3 d ripening at 20 ◦C after 5 and 7 weeks 5 ◦C storage, and had lower expressible juice than ‘Yuval’ nectarines. Cold storage at 0 ◦ C plus ripening reduced flesh browning, woolly texture and flesh bleeding incidence in

Several important combinatorial arrays, after inserting some minus signs, turn out to be involutions when considered as lower triangular matrices. Among these are the Pascal, RNA, and directed animal matrices. These examples and many others are in the Bell subgroup of the Riordan group. We characterize all such pseudo-involutions by means of a single sequence called the Δ-sequence. Finally we compute the Δ-sequences for the powers of a pseudo-involution in the Bell subgroup.

Since the F"q-linear spaces F"q^m and F"q"^"m are isomorphic, an m-fold multisequence S over the finite field F"q with a given characteristic polynomial [email protected]?F"q[x], can be identified with a single sequence S over F"q"^"m with characteristic polynomial f. The linear complexity of S, which will be called the generalized joint linear complexity of S, can be significantly smaller than the conventional joint linear complexity of S. We determine the expected value and the variance of the generalized joint linear complexity of a random m-fold multisequence S with given minimal polynomial. The result on the expected value generalizes a previous result on periodic m-fold multisequences. Moreover we determine the expected drop of linear complexity of a random m-fold multisequence with given characteristic polynomial f, when one switches from conventional joint linear complexity to generalized joint linear complexity.

Using a three-line system of Shaan 2A cytoplasmic male sterility, a hybrid variety rapeseed, Zhongyouza 11, was developed by the combination of traditional methods and a molecular marker-assisted breeding technique. This hybrid variety had high grain yield, high oil content, wide adaptability, and good quality. The oil content of Zhongyouza 11 is steadily above 43% in the three ecological regions along the Yangtze River valley, which is the largest winter oilseed production area in China. The highest oil content of Zhongyouza 11 reached 46.68% in the upper reaches of the Yangtze River valley in 2003-2004, which was the highest among all lines involved in the national regional rapeseed variety trials. In the regional yield trials in Hubei Province, the average yield of Zhongyouza 11 reached 2853 kg ha^(-1) (2002-2004), yielding more than the control variety Zhongshuang 6 by 11.34%. In the national trials, the yield of Zhongyouza 11 reached 2405.7, 2697.3, and 2770.2 kg ha^(-1) in the upper, middle, and lower reaches of the Yangtze River valley, yielding more than the control varieties by 11.52, 12.9, and 14.92%, respectively, in 2003-2005. Both the high oil content and high grain yield contributed to the high oil yield of Zhongyouza 11. The oil yield of Zhongyouza 11 in the national trials reached 1083.3, 1210.2, and 1224.8 kg ha^(-1), yielding more than the controls by 29.42, 27.65, and 20.98%, respectively, in the upper, middle, and lower reaches of the Yangtze River valley. The highest oil yield reached 1369.65 kg ha^(-1) in the middle reach of the Yangtze River valley (2003-2004), with an increase of 46.21% compared to the control. The experimental sites distributed widely along the Yangtze River valley, cover most of the Chinese winter rapeseed production areas. Among the 89 experimental location! years, the yield of Zhongyouza 11 surpassed the controls at 77 location/years in the trials, indicating its wide adaptability. Zhongyouza 11 was the only one that passed the national regional trials in all three regions along the Yangtze River valley simultaneously in 2005. It is also the first rapeseed variety that contained seed oil exceeding 46% and passed the national regional trials. This study shows that heterosis prediction by the means of estimation of genetic distance between parental lines using single sequence repeat (SSR) and sequence related amplified polymorphism (SRAP) markers is an efficient way for the reduction of tedious field trials and the acceleration of breeding procedure.

This work describes an analytical strategy, based on liquid chromatography–tandem mass spectrometry (LC–MS–MS), with a generic chromatographic system in which it is possible to analyse corticosteroids (CORT), β-agonists (BAG), chloramphenicol (CAP) and penicillins (PEN). The same mobile phase solvents and column were used, and only gradient tables and mass spectrometry acquisition methods were changed depending on the family of compounds to analyse. Different batches of final extracts, proceeding from different analytical methods, may be included in a single sequence and run overnight. Sequence programming and LC–MS–MS conditions are included and typical chromatograms are presented. The proposed approach makes the performance of the analysis of veterinary drug residues more simple, cost-effective and less time-consuming.

Rationale and objectives To compare the appropriate pulse sequences for interventional device guidance during magnetic resonance (MR) imaging at 0.2 T and to evaluate the dependence of sequence selection on the anatomic region of the procedure. Materials and methods Using a C-arm 0.2 T system, four interventional MR sequences were applied in 23 liver cases and during MR-guided neck interventions in 13 patients. The imaging protocol consisted of: multislice turbo spin echo (TSE) T 2 w, sequential-slice fast imaging with steady precession (FISP), a time-reversed version of FISP (PSIF), and FISP with balanced gradients in all spatial directions (True-FISP) sequences. Vessel conspicuity was rated and contrast-to-noise ratio (CNR) was calculated for each sequence and a differential receiver operating characteristic was performed. Results Liver findings were detected in 96% using the TSE sequence. PSIF, FISP, and True-FISP imaging showed lesions in 91%, 61%, and 65%, respectively. The TSE sequence offered the best CNR, followed by PSIF imaging. Differential receiver operating characteristic analysis also rated TSE and PSIF to be the superior sequences. Lesions in the head and neck were detected in all cases by TSE and FISP, in 92% using True-FISP, and in 84% using PSIF. True-FISP offered the best CNR, followed by TSE imaging. Vessels appeared bright on FISP and True-FISP imaging and dark on the other sequences. Conclusion In interventional MR imaging, no single sequence fits all purposes. Image guidance for interventional MR during liver procedures is best achieved by PSIF or TSE, whereas biopsies in the head and neck are best performed using FISP or True-FISP sequences.

We attempted to distinguish walking on level ground from walking on a stairway using waist acceleration signals. A triaxial accelerometer was fixed to the subject's waist and the three acceleration signals were recorded by a portable data logger at a sampling rate of 256 Hz. Twenty healthy male subjects were asked to walk through a corridor and up and down a stairway as a single sequence, without any instruction. The data were analyzed using discrete wavelet transform. Walking patterns were classified in two stages. In the first stage, the times when the walking pattern changed were detected using the low-frequency component of the anteroposterior acceleration (LF(A)) and of the vertical acceleration (LF(V)). In the second stage, the three types of walking patterns were classified by comparing powers of wavelet coefficients in the vertical direction (P(WCV)) and in the anteroposterior direction (RP(WCA)). Changes in walking patterns could be detected by using either LF(A) or LF(V). Walking down stairs could be distinguished from the other types of walking as it gave the largest value in P(WCV), and walking up stairs could be discriminated from level walking using RP(WCA). Level and stairway walking could be classified from continuous records of waist acceleration.

The spatial distribution of inter-layer shear zones is studied, based on the fully mapped inter-layer shear zones at the Gaobazhou dam site on the Qingjiang River in Hubei province, China. The field observations revealed that two types of inter-layer shear zone, under-developed and well-developed, are distributed differently. The former are associated with the incompetent rock layers, and the latter are controlled by the inter-bed folds and lithological properties of the strata. To represent their lithological properties geomechanically, data on strength by the Schmidt hammer test and thickness of each field-identified rock layer were collected to form strength sequences and thickness sequences. The adjacent rock layers of similar strength are then grouped, and two grouped sequences are combined into a single sequence, whose individual term is the strength weighted by the exponential function value of the centralized thickness (SCT). The rescaled range ( R / S ) analysis results of SCT (SCT-R/S), taking into account the presence of inter-bed folds, are in good agreement with R / S analysis results of the spacing sequence of the well-developed inter-layer shear zones. Thus the SCT-R/S model has the potential to predict their spatial distributions.

The serpins (SERine Proteinase INhibitors) are a family of proteins with important physiological roles, including but not limited to the inhibition of chymotrypsin-like serine proteinases. The inhibitory mechan- ism involves a large conformational change known as the S → R (stressed → relaxed) transition. The largest structural differences occur in a region around the scissile bond called the reactive centre loop: In the native (S) state, the reactive centre is exposed, and is free to interact with proteinases. In inhibitory serpins, in the cleaved (R) state the reactive centre loop forms an additional strand within the β-sheet. The latent state is an uncleaved state in which the intact reactive centre loop is integrated into the A sheet as in the cleaved form, to give an alternative R state. The serpin structures illustrate detailed control of conformation within a single protein. Serpins are also an unusual family of proteins in which homologues have native states with different folding topologies. Determination of the structures of inhibitory serpins in multiple conformational states permits a detailed analysis of the mechanism of the S → R transition, and of the way in which a single sequence can form two stabilised states of different topology. Here we compare the conformations of α 1 -antitrypsin in native and cleaved states. Many protein conformational changes involve relative motions of large rigid subunits. We determine the rigid subunits of α 1 -antitrypsin and analyse the changes in their relative position and orientation. Knowing that the conformational change is initiated by cleavage at the reactive centre, we describe a mechanism of the S → R transition as a logical sequence of mechanical effects, even though the transition likely proceeds in a concerted manner.

Polymerase chain reactions (PCRs) were carried out with DNAs of eight tomato species using primers directed at the reverse transcriptase domain of Ty3 / gypsy -like LTR retrotransposons. All DNAs gave PCR products of the expected size which, after cloning and sequencing, were confirmed as representing Ty3 / gypsy -like elements. The sequences were heterogeneous, only 3 of the 16 being identical and the most diverse showing 124/426 pairwise nucleotide differences. Multiple alignment and construction of neighbor joining trees divided the sequences into six groups, three comprising five, three, and five sequences respectively, and the other three containing a single sequence each.

Two seemingly contradictory principles describe conditioned response (CR) acquisition when a sequence of two conditioned stimuli (CSA-CSX) signal the unconditioned stimulus (US) for the rabbit′s nictitating membrane (NM) response. For long CSA-CSX intervals, responding to CSA shows facilitation similar to second-order conditioning. For shorter CSA-CSX intervals, responding to CSX shows impairments similar to blocking and overshadowing. Whether and how the two processes interact has been unclear. The present study interpolated extra CSs between CSA and CSX, thus introducing the full range of CS-CS intervals into a single sequence. The interpolated CSs maintained the facilitation of CRs to CSA and progressively impaired CRs to CSX. The interpolated CSs themselves tended to show facilitated CR acquisition. Thus, the two processes can act concurrently. In theoretical terms, the higher-order CSs appear to have a parasitic relationship to the first-order CS, effectively stealing its associative strength.

OBJECTIVE: Different culture media have long been used for extended sequential culture. Encourage a minimum of embryo manipulation and optimization of culture conditions is the key to the success of the IVF program. Obviously, if possible at the lowest cost. Using a culture media that allows this objective must be explored. DESIGN: To compare blastulation rate in two different systems: sequential versus single steps culture from day 1 to day 5. MATERIALS AND METHODS: A prospective analysis in 2 french private IVF centers was performed during 6 months (October 2012-March 2013). 260 patients were involved. The same protocole was applied in the 2 different IVF lab environnements. In random half of the oocytes is treated with a sequential system (Combination of Ferticult from Fertipro follows by CCM from Vitrolife), the other half of the same cohorte with a single continous system (CSC from Irvine). All embryos are cultured by group (0,7ml) under oil overlay at 37C with 6% CO2. Outcome measured of interest were number of Blastocyts obtain at Day 5 and kinetics of blastocyst. (french classification). Were assigned the best blastocyst for transfert coming if possible from a single sequence. (Student t-test and chi square test). RESULTS: The results are comparable in both centers. The mean of MII oocytes observed on 260 cases is 11,2. The average rate of fertilization is 78,3%. The blastulation rate obtained with the sequential media are is 40.7% vs 51.5% with the SCS media (p

Finding of transcription factor binding motifs (TFBMs) is essential for identifying the detailed transcriptional regulation networks. In this study, we developed a novel algorithm for identifying the TFBMs by using the genome DNA sequence. We compared the accuracy of our algorithm with that of the conventional ones by exploiting ChIP-on-chip genome DNA sequence fragments, as test data, which were extracted by treatments to induce specific TFBMs of S. cerevisiae and human estrogen receptor (ER) expressed in human MCF-7 breast cancer cells. As a result of our calculation of the S. cerevisiae data, our algorithm identified 69 % known TFBMs from 65 datasets, each of which is corresponding to distinct TFBMs. In contrast, the conventional algorithms identified 63 % (BioProspector), 49 % (MDscan), and 52 % (MEME); here, the default parameter set was used for each identification system. Also, for ER elements (ERE), our algorithm exactly identified the position-specific scoring matrix (PSSM) using the human ER data, whereas the conventional algorithms did not. If single sequence repeats (SSLs) are removed from the ER data, BioProspector identified the PSSM of the human ERE. Accordingly, our system is expected to identify unknown TFBMs as well as known ones using genome DNA sequences without editing/tuning the parameter set used in our identification system. Further, identification of co-regulated known/unknown transcription factors is now going on by using experimental data obtained by DNA microarray techniques and the cap analysis gene expression (CAGE) systems.

An NMR parallel imaging method and apparatus in a single sequence has a plurality of RF pulses (RF EXCITE 90°) applied substantially simultaneously, each having a different frequency, in the same contiguous time period in a subinterval of time (τ) during which the select slice magnetic gradient (SS) is applied, to activate a plurality of different physical slices. The refocusing RF pulses also comprise a plurality of RF pulses (RF EXCITE 180°) each having a different frequency, applied non-simultaneously but within the same slice select magnetic gradient (SS) in the same subinterval time (τ). A plurality of echo signals (RF RECEIVE) from the plurality of different excited slices then read out during the same single read out magnetic pulse (RO) in the same subinterval. The method and apparatus of the present invention can be applied in MRI spin echo, pre-saturation or inversion.

A single sequence for the formation of a plurality of images of the same selected nuclei but with each image having a different contrast characteristic is disclosed. MRI signals are acquired during the first time interval which comprises a plurality of first intervals with each of the first intervals being substantially the same. During the first time interval, the selected nuclei are phase encoded by a different magnetic phase encoding gradient. The sequence continues to acquire a second plurality of MRI signals from the same plurality of selected nuclei. The second time interval comprises a plurality of second intervals different from the first intervals. During the second interval, the selected nuclei are phase encoded by a different magnetic phase encoding gradient but with the magnetic phase encoding gradient being the same as or a subset of those during the first time interval. The data from the first and second plurality of MRI signals are regrouped and portions are reused to form a plurality of regrouped data sets. Each of the regrouped data sets is then fourier transformed to produce a plurality of images of the selected nuclei. Each image is of the same plurality of selected nuclei but with different contrast characteristics.

Contributions to a symposium of the IUGS Subcommission on Cambrian Stratigraphy at the International Geological Congress in Montreal in 1972 are the basis of this paper which is intended to give guidance to further work of what is now a Working Group on the Precambrian—Cambrian boundary of the International Geological Correlation Programme (UNESCO/IUGS). The proposed principles for the definition of the boundary are based on those accepted by the Commission on Stratigraphy, particularly on stratigraphic classification and on defining the Silurian—Devonian boundary. These matters are discussed by the authors in general terms and by W.B. Harland in terms of procedure. They are illustrated by examples of stratigraphic sequences across the boundary in Siberia given by A.Yu. Rozanov and discussed critically by V.E. Savitsky. New relevant discoveries of Early Cambrian faunas and their stratigraphic setting are reviewed by A. Boudda et al. P.E. Cloud's contribution, published elsewhere, and work in Australia are reviewed by the authors. The conclusions, based not only on the symposium material but also on current opinion, are that no single sequence which could serve as a reference standard for the Precambrian—Cambrian boundary has yet been identified but that many significant ones have been described which will be further examined. While the general limits for the choice of a boundary definition should lie between the horizons with fossils of Ediacaran type and those with diversified trilobite assemblages, a number of “Working Reference Points” exist in that interval which are correlatable horizons of faunal change. These cannot be defined simply as horizons of first appearance.

Let G be a connected amenable group (thus, an extension of a connected normal solvable subgroup R by a connected compact group K = G R ). We show how to explicitly construct sequences { U n } of compacta in G in terms of the structural features of G which have the following property: For any “reasonable” action G × L p ( X , μ ) ↓ L p ( X , μ ) on an L p space, 1 p f ∈ L p ( X , μ ), the averages A n f= 1 |U n | ∫ U n T g −1f dg (|E|= left Haar measure in G) converge in L p norm, and pointwise μ-a.e. on X , to G -invariant functions f∗ in L p ( X , μ ). A single sequence { U n } in G works for all L p actions of G . This result applies to many nonunimodular groups, which are not handled by previous attempts to produce noncommutative generalizations of the pointwise ergodic theorem.

The conceptions on shops and factories of a group of 3rd-grade children were assessed by means of the Piagetian clinical method. Factorial analysis showed that children's answers about the two economic institutions yielded two distinct factors. Children were then divided into three groups (one control and two experimental); children in the experimental groups were taught, by means of two different training procedures, how the shopkeeper can earn a profit. A post-test interview, one month later, showed that both experimental groups had progressed in the target notion; however, children did not generalize to the factory what they had learned about shops. According to these results, 3rd-graders' thinking about economics consists of separate part-systems, which will eventually become integrated as children grow older.