The 11-year cycle in human births

The annual numbers of human births were analyzed with regard to an 11-year cycle. The annual values were obtained from seven different regions: Australia, Germany, England and Wales, New Zealand, Japan, Switzerland, and the USA. Fifty-five annual values were obtained from each region for the years 1930 to 1984, comprising approximately five sunspot cycles. For each region the annual values were formed into 5 by 11 matrices; the eleven column means obtained were standardized, and plotted. A periodic regression technique, utilizing the fitting functions of the Fourier series, was used to evaluate the temporal order in the column means. Eleven-year rhythms were found and compared with solar and geophysical variables. Correlations were found with sunspots and solar flares, with terrestrial measures of magnetic disturbances (the magnetic indices derived from the K-index), and with temperature. The correlation of conceptions with the 11-year solar cycle may be a potential guide in the selection of further variables for the control and regulation of the rhythms in human conceptions.     

Flow cytofluorimetric determination of protein distribution throughout the cell cycle

Quantitative treatment of multiparametric determination on cells using flow cytofluorometry was made possible by the development of a computer program that allows the relative quantification of a specific protein as a function of the position of cells during the cell cycle. This type of analysis provides interesting information about the distribution of a given protein throughout the cell cycle. Four examples showing the distribution of specific proteins illustrate such a quantification during the cell cycle in two different cell lines. The program also allows for the handling of a series of histograms obtained by the analysis of protein distribution as a function of DNA content in relation to a third parameter. To illustrate possible applications for this program, the evolution of the distribution of two proteins, the oncoprotein p53 and the histone H1(0), during the induced differentiation of murine erythroleukemia cells has been studied.     

The distribution of events in the human menstrual cycle

Daily reports of 85 married couples concerning their sexual behaviour for about 3 menstrual cycles per couple were organized according to menstrual events by using six techniques of aggregation. While there were some similarities among the different displays, including an apparent peak about 6 days before mid-cycle, different methods of aggregation produce widely different frequency curves. It is concluded that there is no single method of display of events of the menstrual cycle which will fit all investigations.     

Signature of recent historical events in the European Y-chromosomal STR haplotype distribution

Previous studies of human Y-chromosomal single-nucleotide polymorphisms (Y-SNPs) established a link between the extant Y-SNP haplogroup distribution and the prehistoric demography of Europe. By contrast, our analysis of seven rapidly evolving Y-chromosomal short tandem repeat loci (Y-STRs) in over 12,700 samples from 91 different locations in Europe reveals a signature of more recent historic events, not previously detected by other genetic markers. Cluster analysis based upon molecular variance yields two clearly identifiable sub-clusters of Western and Eastern European Y-STR haplotypes, and a diverse transition zone in central Europe, where haplotype spectra change more rapidly with longitude than with latitude. This and other observed patterns of Y-STR similarity may plausibly be related to particular historical incidents, including, for example, the expansion of the Franconian and Ottoman Empires. We conclude that Y-STRs may be capable of resolving male genealogies to an unparalleled degree and could therefore provide a useful means to study local population structure and recent demographic history.L. Roewer and P.J.P. Croucher contributed equally to this paper.This revised version was published online in February 2005 with corrections to the addresses of the authors of the Forensic Y-Chromosome Research Group.     

The distribution of intratracheally administered plutonium-239 throughout the skeletal bones]

The data are presented on distribution of the intratracheally administered plutonium-239 within the skeleton bones. Plutonium was found to be distributed non-uniformly within the skeleton: it was concentrated mainly in the bones where the trabecular fraction of the bone tissue was most manifest. The results obtained were supported by the correlation analysis.     

The asymmetric spatial distribution of bacterial signal transduction proteins coordinates cell cycle events

The polar localization of signaling proteins that are essential for Caulobacter cell cycle control is temporally regulated. Here we provide evidence that phosphorylation of the essential response regulator, DivK, is required for both its function and its cell cycle-regulated localization. The asymmetric location of the DivJ and PleC histidine kinases and their antagonistic activities on the cellular concentration of phosphorylated DivK provide positional and temporal information for the ordered sequence of DivK localization during the cell cycle. DivJ activity on DivK affects its correct localization, which, in turn, is required for PleC function. Since DivJ and PleC regulate different cell cycle events, the interconnected function of these two histidine kinases through localization of a common response regulator provides a mechanism for coordinating cell cycle progression. Study of a DivK homolog in the morphologically symmetric bacterium Sinorhizobium meliloti suggests that this type of cell cycle mechanism is widespread in prokaryotes.     

ami1, an orthologue of the Aspergillus nidulans apsA gene, is involved in nuclear migration events throughout the life cycle of Podospora anserina

The Podospora anserina ami1-1 mutant was identified as a male-sterile strain. Microconidia (which act as male gametes) form, but are anucleate. Paraphysae from the perithecium beaks are also anucleate when ami1-1 is used as the female partner in a cross. Furthermore, in crosses heterozygous for ami1-1, some crozier cells are uninucleate rather than binucleate. In addition to these nuclear migration defects, which occur at the transition between syncytial and cellular states, ami1-1 causes abnormal distribution of the nuclei in both mycelial filaments and asci. Finally, an ami1-1 strain bearing information for both mating types is unable to self-fertilize. The ami1 gene is an orthologue of the Aspergillus nidulans apsA gene, which controls nuclear positioning in filaments and during conidiogenesis (at the syncytial/cellular transition). The ApsA and AMI1 proteins display 42% identity and share structural features. The apsA gene complements some ami1-1 defects: it increases the percentage of nucleate microconidia and restores self-fertility in an ami1-1 mat+ (mat-) strain. The latter effect is puzzling, since in apsA null mutants sexual reproduction is quite normal. The functional differences between the two genes are discussed with respect to their possible history in these two fungi, which are very distant in terms of evolution.     

Regulation of DNA repair throughout the cell cycle

The repair of DNA lesions that occur endogenously or in response to diverse genotoxic stresses is indispensable for genome integrity. DNA lesions activate checkpoint pathways that regulate specific DNA-repair mechanisms in the different phases of the cell cycle. Checkpoint-arrested cells resume cell-cycle progression once damage has been repaired, whereas cells with unrepairable DNA lesions undergo permanent cell-cycle arrest or apoptosis. Recent studies have provided insights into the mechanisms that contribute to DNA repair in specific cell-cycle phases and have highlighted the mechanisms that ensure cell-cycle progression or arrest in normal and cancerous cells.     

Inducibility of metallothionein throughout the cell cycle.

Synchronized Chinese hamster cells were induced with ZnCl2 at multiple stages of the cell cycle and labeled with [35S]cysteine, and the 35S-labeled proteins were isolated and separated into metallothionein and nonmetallothionein fractions. Metallothionein was found to be inducible in all stages of the cell cycle and in G1-arrested cells.     

Uneven distribution of amino acid substitutions throughout the amino acid sequence of homologous proteins]

A set of aligned homologous protein sequences is divided into two groups consisting of m and n most related sequences. The value of position variability for homologous protein sequences is defined as a number of failures to coincide in the intergroup comparison of all possible m*n pairs of amino acid residues in that position divided by m*n. The position variability value plotted versus the sequence position number with a window of 10 positions gives the intergroup local variability profile. Area S of the figure included between the local variability profile and the straight line corresponding to the mean local variability value is compared with the average area Sr for 1000 random homologous protein families. If S is greater than Sr by more than 2 standard deviation units sigma r, the local variability profile is assumed to contain peaks and hollows corresponding to significant variable and conservative regions of the sequences. The profile extrema containing the area surplus delta S = S-(Sr+ 2 sigma r) are cut off by two straight lines to locate significant regions. The difference (S-Sr) given in standard deviation units sigma r is believed to be the amino acid substitution overall irregularity along the homologous protein sequences OI = (S-Sr)/sigma r. The significant conservative and variable regions of six homologous sequence families (phospholipase A2, cytochromes b, alpha-subunits of Na,K-ATPase, L- and M-subunits of photosynthetic bacteria photoreaction centre and human rhodopsins) were identified. It was shown that for artificial homologous protein sequences derived by k-fold lengthening of natural protein sequences, the OI value rises as square root of k. To compare the degree of substitution irregularity in homologous protein sequence families of different lengths L the value of standard substitution overall irregularity for L = 250 is proposed.     

Goals of stability evaluation throughout the vaccine life cycle

Stability studies play a critical role in assuring product quality at all points in the vaccine life cycle. At and after licensure, stability studies on quality attributes (including potency) provide a critical link between marketed and clinically evaluated vaccine product, addressing important regulatory concerns by assuring that product quality is maintained throughout the dating period. During development, stability studies are done to assure product quality and to obtain the data needed to support licensure. Stability studies may also be performed after licensure to assure that product continues to perform as it did pre-licensure, as well as to evaluate the effect on product quality of deliberately introduced manufacturing changes. At each phase in the product life cycle, it is important to consider the goals of stability evaluation and to perform appropriate statistical analyses in order to assure and reach appropriate conclusions about product quality.     

Low diversity and abundance of root endophytes prevail throughout the life cycle of an annual halophyte

Plants growing in highly saline soils harbor unique communities of fungal root endophytes. We aimed to gain insight into how these communities are established in natural plant populations. We used cultivation-based and molecular approaches to examine root-endophytic colonization in the annual halophyte Salicornia patula at three time points over a 5-month period, from establishment to flowering. At the last sampling, the endophytic community of S. patula was compared to that in the related but perennial halophyte Arthrocnemum macrostachyum. The presence of root endophytes in S. patula was negligible at the first two sampling times, and remained low at the last sampling compared to A. macrostachyum. The latter species showed a well-established endophytic community in its roots that differed from that in S. patula, which was dominated by members of Pleosporales. Although such differences could be partially due to the host lifestyle, the possibility of a strong effect of the substratum could not be excluded. Altogether, our data indicate that the fungal endophytic colonization of roots is a slow process under salt stress. Therefore, we suggest that, in contrast to what is proposed for other systems, endophyte symbioses are unlikely to impact the development of the short-life-cycled S. patula living in these environments.     

Characterization of [11C]vorozole binding in ovarian tissue in rats throughout estrous cycle in association with conversion of androgens to estrogens in vivo and in vitro

Estrogen levels vary in a cyclic fashion during the rat estrous cycle, reaching peak concentrations during proestrus. Previously, it was suggested that the preovulatory peak in estrogen production in rats in vivo is regulated by other control mechanisms than concentration of precursor and amount of aromatase enzyme, changing the specific activity of the enzyme. To explore this hypothesis, ovarian binding of [11C]vorozole in vivo and in vitro, representing the amount of active aromatase, and conversion activity of ovarian homogenate were assayed together with serum androstenedione (A4) and estradiol-17beta (E2) levels during the estrous cycle in rats. The reducing ovarian [11C]vorozole binding in vivo from proestrus +4 up to +8h might indicate that the ovarian aromatase is blocked, probably to prevent premature increase of E2 levels. Thereafter (between proestrus +9 and +13h), the binding dramatically increases (aromatase enzyme is unblocked), to enable increased E2 synthesis. In addition, during the latter period, serum E2 levels were strongly correlated with serum A4 levels after adjustment for amount of ovarian aromatase (P=0.03), but not with amount of aromatase adjusted for levels of A4 (P=0.13), which might indicate changes in specific activity of the aromatase enzyme. Significant correlation between Kd and serum E2 levels during the same period indicated that aromatase-precursor affinity might be involved in the regulation of the enzyme-specific activity. This conclusion is done assuming that [11C]vorozole binding mimics that of the substrate (A4). The [11C]vorozole in vivo technique keeps auto- and paracrine mechanisms intact, and might therefore yield additional information about biological processes compared with traditional in vitro techniques.     

Life cycle sustainability analysis applied to an innovative configuration of concentrated solar power

Purpose

Life cycle sustainability analysis (LCSA) is being developed as a holistic tool to evaluate environmental, economic and social impacts of products or services throughout their life cycle. This study responds to the need expressed by the scientific community to develop and test LCSA methodology, by assessing the sustainability of a concentrated solar power (CSP) plant based on HYSOL technology (an innovative configuration delivering improved efficiency and power dispatchability).

Methods

The methodology proposed consists of three stages: goal and scope definition, modelling and application of tools, and interpretation of results. The goal of the case study was to investigate to what extent may the HYSOL technology improve the sustainability of power generation in the Spanish electricity sector. To this purpose, several sustainability sub-questions were framed and different analysis tools were applied as follows: attributional and consequential life cycle assessment, life cycle cost (LCC) analysis and multiregional input-output analysis (MRIO), and social life cycle assessment (S-LCA) in combination with social risk assessment (with the Social Hotspots Database). Visual diagrams representing the sustainability of the analysed scenarios were also produced to facilitate the interpretation of results and decision making.

Results and discussion

The results obtained in the three sustainability dimensions were integrated using a “questions and answers” layout, each answer describing a specific element of sustainability. The HYSOL technology was investigated considering two different operation modes: HYSOL BIO with biomethane as hybridization fuel and HYSOL NG with natural gas. The results indicated that the deployment of HYSOL technology would produce a reduction in the climate change impact of the electricity sector for both operation modes. The LCC analysis indicated economic benefits per MWh for a HYSOL NG power plant, but losses for a HYSOL BIO power plant. The MRIO analysis indicated an increase in goods and services generation, and value added for the HYSOL technology affecting primarily Spain and to a lower extent other foreign economies. The social analysis indicated that both alternatives would provide a slight increase of social welfare Spain.

Conclusions

The methodological approach described in this investigation provided flexibility in the selection of objectives and analysis tools, which helped to quantify the sustainability effect of the system at a micro and meso level in the three sustainability dimensions. The results indicated that the innovation of HYSOL power plants is well aimed to improve the sustainability of CSP technology and the Spanish electricity sector.

     

Sulfur distribution in lake sediment profiles as an index of historical depositional patterns

Changes in S concentration in sediment profiles from South Lake (Adirondack region, New York, USA) and Ledge Pond (western Maine, USA) indicated an increased input of S beginning around 1850. This S was probably derived from anthropogenic sources. The S budget for South Lake indicated that sedimentation of seston rich in S (0.9% dry mass) accounts for most of the input of S in sediment. Sulfur in both seston and sediment is primarily organic (57 and 22% ester sulfate, 32 and 52% carbon-bonded S, respectively). The transformation and translocation of organic S constitutes a major pathway of S flux in South Lake.     

Cytochemistry of histones throughout the division cycle in meristematic cells

Summary We have been able to follow the increase in nuclear histones along the division cycle, using a natural synchronous meristematic cell population labelled by caffeine as binucleate. We have thus found a parallel increase in DNA and histone along the S period. Some increase in nuclear histones during the G₁ and G₂ has also been detected. At the same time a high rise of stainable histone in the nuclei in prophase has been found.Changes in the composition of nuclear histones have been followed counting the percentage of arginine-rich histones in the total histone content. Two peaks located at the beginning and at the end of the S period as well as a sharp descent of the percentage of arginine-rich histone in the prophasic nucleus have been found.     

Phosphorylation of the lysine-rich histones throughout the cell cycle.

The phosphorylating of the lysine-rich histone at various stages in the cell cycle has been studied. In rapidly dividing cell populations the lysine-rich histone is phosphorylated rapidly after synthesis and more slowly once bound to the chromosome. The half-life of hydrolysis of such interphase phosphorylation in 5 hr except during mitosis when the phosphata hydrolysis increases almost three-fold. During mitosis there is extensive phosphorylation at sites different from those phosphorylated during interphase and a smaller measure of sites common to both mitotic and interphase cells. The sites of mitotic phosphorylation are most critically distinguished from those phosphorylated in interphase by the rapidly hydrolysis of M-phase phosphohistone when the cells divide and enter the G1 phase of the cell cycle.     

Population identification of western hemisphere shorebirds throughout the annual cycle

Identification of relationships among geographically distinct populations of migratory species can provide an understanding of breeding and natal philopatry, migration pathways, and population mixing during winter. We used random amplified polymorphic DNA (RAPD) analyses to search for markers specific to difficult-to-differentiate shorebird species (e.g. long-billed dowitcher Limnodromus scolopaceus and short-billed dowitcher L. griseus ) as well as geographically distinct breeding populations of Hudsonian godwits Limosa haemastica , red-necked phalaropes Phalaropus lobatus , semipalmated plovers Charadrius semipalmatus , dunlin Calidris alpina , pectoral sandpipers C. melanotos , semipalmated sandpipers C. pusilla and western sandpipers C. mauri . Markers clearly differentiated all shorebird species. Estimates of population differentiation varied greatly among species ( F _ST= 0.095–0.685) and correlated with interspecific variation in philopatry and geographical separation of breeding populations. We assigned individuals to putative breeding locales with greater certainty in well-differentiated species than in poorly differentiated species. Our findings indicate specific phylogeographical structure varies among species, which has strong implications for conservation of habitats within migratory corridors. We suggest that RAPDs are useful in identifying geographical populations of migratory species and that molecular markers should be considered for tracking migratory birds throughout the annual cycle.