The role of Mexico in the first oil shortage: 1918-1922, an international perspective

In 1921 Mexico produced a quarter of world s petroleum, making the country the secondlargest producer in the world, but by 1930 it only accounted for 3 per cent of world sproduction. To date the discussion has mostly relied on events taking place in Mexico forexplaining the decline of the industry. Very little attention has been placed todevelopments in petroleum industry elsewhere, except Venezuela. Practically noattention has been paid to the reasons for the rise of oil output in Mexico. This neglectsthe massive changes taking place in the petroleum industry worldwide during the GreatWar years and its aftermath, and overall ignores the shortage of oil that occurred in theworld s markets between 1918-1921. These are crucial events in order to understand theearly rise of the Mexican oil industry and set the basis for a better understanding of thesubsequent sudden decline.

Human immunodeficiency virus type 1 fitness is a determining factor in viral rebound and set point in chronic infection.

Human immunodeficiency virus type 1 (HIV-1) isolates from 20 chronically infected patients who participated in a structured treatment interruption (STI) trial were studied to determine whether viral fitness influences reestablishment of viremia. Viruses derived from individuals who spontaneously controlled viremia had significantly lower in vitro replication capacities than viruses derived from individuals that did not control viremia after interruption of antiretroviral therapy (ART), and replication capacities correlated with pre-ART and post-STI viral set points. Of note, no clinically relevant improvement of viral loads upon STI occurred. Virus isolates from controlling and noncontrolling patients were indistinguishable in terms of coreceptor usage, genetic subtype, and sensitivity to neutralizing antibodies. In contrast, viruses from controlling patients exhibited increased sensitivity to inhibition by chemokines. Sensitivity to inhibition by RANTES correlated strongly with slower replication kinetics of the virus isolates, suggesting a marked dependency of these virus isolates on high coreceptor densities on the target cells. In summary, our data indicate that viral fitness is a driving factor in determining the magnitude of viral rebound and viral set point in chronic HIV-1 infection, and thus fitness should be considered as a parameter influencing the outcome of therapeutic intervention in chronic infection.

Exploiting fitness distance correlation of set covering problems

The set covering problem is an NP-hard combinatorial optimization problemthat arises in applications ranging from crew scheduling in airlines todriver scheduling in public mass transport. In this paper we analyze searchspace characteristics of a widely used set of benchmark instances throughan analysis of the fitness-distance correlation. This analysis shows thatthere exist several classes of set covering instances that have a largelydifferent behavior. For instances with high fitness distance correlation,we propose new ways of generating core problems and analyze the performanceof algorithms exploiting these core problems.

Subset correspondence analysis: Visualizing relationships among a selected set of response categories from a questionnaire survey

It is shown how correspondence analysis may be applied to a subset of response categories from a questionnaire survey, for example the subset of undecided responses or the subset of responses for a particular category. The idea is to maintain the original relative frequencies of the categories and not re-express them relative to totals within the subset, as would normally be done in a regular correspondence analysis of the subset. Furthermore, the masses and chi-square metric assigned to the data subset are the same as those in the correspondence analysis of the whole data set. This variant of the method, called Subset Correspondence Analysis, is illustrated on data from the ISSP survey on Family and Changing Gender Roles.

New insights into the molecular basis of desmoplakin- and desmin-related cardiomyopathies.

Desmosomes are intercellular adhesive complexes that anchor the intermediate filament cytoskeleton to the cell membrane in epithelia and cardiac muscle cells. The desmosomal component desmoplakin plays a key role in tethering various intermediate filament networks through its C-terminal plakin repeat domain. To gain better insight into the cytoskeletal organization of cardiomyocytes, we investigated the association of desmoplakin with desmin by cell transfection, yeast two-hybrid, and/or in vitro binding assays. The results indicate that the association of desmoplakin with desmin depends on sequences within the linker region and C-terminal extremity of desmoplakin, where the B and C subdomains contribute to efficient binding; a potentially phosphorylatable serine residue in the C-terminal extremity of desmoplakin affects its association with desmin; the interaction of desmoplakin with non-filamentous desmin requires sequences contained within the desmin C-terminal rod portion and tail domain in yeast, whereas in in vitro binding studies the desmin tail is dispensable for association; and mutations in either the C-terminus of desmoplakin or the desmin tail linked to inherited cardiomyopathy seem to impair desmoplakindesmin interaction. These studies increase our understanding of desmoplakin-intermediate filament interactions, which are important for maintenance of cytoarchitecture in cardiomyocytes, and give new insights into the molecular basis of desmoplakin- and desmin-related human diseases.

Iowa DOT Quick Tour, May 12, 2009

The DOT, created by the Iowa Legislature, began operating July 1,1975. The newly formed Department of Transportation had a staff of 4,568 full-time equivalents (FTEs). These employees and their responsibilities came from the Highway Commission, Reciprocity Board, Aeronautics Commission, and parts of the Commerce Commission, Department of Revenue and Finance, Department of Public Safety and the Energy Policy Council. The DOT continually looks at ways to become more efficient in serving our customers. As a result the current workforce equals approximately 3,049 full-time employees. The seven transportation commissioners set policy for the department and are appointed by the governor, with no more than four from one political party. Membership on the commission is gender-balanced. Commissioners are confirmed by the Iowa Senate and serve on a staggered basis for four-year terms. Commission meetings are usually held monthly in Ames. The meetings are open to the public and follow a printed agenda.

Atypical EPO profiles in anti-doping analyses

Résumé : Erythropoietin (EPO) is a glycoprotein hormone endogenously produced by the kidney, whose main physiological role is the stimulation of erythropoiesis. Since the beginning of the nineties, recombinant human EPO (rhEPO), a potent anti-anaemia treatment drug, has been manufactured by pharmaceutical industries. However, the erythropoiesis stimulating power of rhEPO was rapidly misused by unscrupulous athletes in order to improve their performances in endurance sports. Endogenous EPO has the same amino-acid backbone as most of recombinant forms; the molecules however differ through their respective glycosylation patterns. This difference constitutes the basis of the usual EPO screening test (IEF) developed in 2000 and still currently used in all anti-doping laboratories of the world. Nowadays, 3 EPO generations have been commercialized. The fight against EPO abuse is a continuous challenge for anti-doping laboratories. The diversity of recombinant EPO forms and the continuous development of new ones considerably confuse the identification of EPO doping. Several facets of this fight were investigated in this work. One of the limiting aspects of doping agents screening is the availability of positive samples. Therefore, 2nd and 3rd generation EPOS, namely NESP and C.E.R.A., were injected to healthy subjects in the frame of pilot clinical studies. These latter allowed to review the current EPO identification criteria defined by the World Anti-Doping Agency (WADA) in the case of NESP and to validate and implement a new assay targeting C.E.R.A. in human serum. Both studies resulted in the determination of the respective detection windows of NESP and C.E.R.A. in biological fluids. Following that, Dynepo, a 1st generation EPO presenting similarities with the endogenous form, was also in the centre of a similar clinical study. Our work aimed to overcome the actual identification criteria, which are not adapted to Dynpeo, and to propose an alternative pattern classification method based on the discriminant analysis of IEF EPO profiles. This method might be validated for other EPO forms in the future. The detection window of this molecule was also determined. Under particular conditions, confounding effects can complicate the identification of EPO in biological matrices. For example, athletes having performed a strenuous physical effort can excrete modified isoforms of endogenous EPO, making it very similar to some recombinant forms. Such phenomena, called effort urines, were reproduced under controlled conditions and, after characterization of effort EPO, an urinary biochemical marker was proposed to unequivocally identify effort urines. It also happens that EPO analyses fail to detect endogenous levels of EPO. Such profiles were thoroughly investigated and potential causes identified. Natural reasons relying on urine properties and test specificity were underlined, but the possible addition of adulterant agents in urine samples was also considered. Therefore, a simple biochemical assay targeting the suspected substances was set up. Our work was based on the characterization of atypical EPO profiles from different origins. Therefore, 3 EPO molecules representing the 3 generations of the drug and 2 confounding effects confusing the results interpretation were studied. These studies resulted in tangible applications for the laboratory, the best example of which being the C.E.R.A. assay, but also in scientific findings allowing to improve our comprehension of EPO doping in sport.

Molecular basis of coagulation factor V deficiency caused by the R1698W inter-domain mutation.

Coagulation factor V (FV) deficiency is characterised by variable bleeding phenotypes and heterogeneous mutations. To add new insights into the FV genotype-phenotype relationship, we characterised the R1698W change in the A3 domain, at the poorly investigated interface with the A2 domain. The FV R1698W mutation was responsible for a markedly reduced expression level (10% of FV-WT) and specific activity in thrombin generation (0.39). Interestingly, the FVa1698W showed rapid activity decay upon activation due to increased dissociation rate between the heavy and light chains. The importance of the size and charge of the residue at position 1698 was investigated by three additional recombinant mutants, FVR1698A, FVR1698Q, and FVR1698E. FVR1698A and FVR1698Q expression (30 and 45% of FV-WT), specific activity (both 0.57) and stability were all reduced. Noticeably, FVR1698E showed normal activity and stability despite poor expression (10% of FV-WT). These data indicate the essential role of R1698 for normal biosynthetic process and support local flexibility for positively or negatively charged residues to produce stable and functional A3-A2 domain interactions. Their experimental alteration produces a gradient of FV defects, which help to interpret the wide spectrum of phenotypes in FV-deficient patients.

Variability of apparently homogeneous soilscapes in São Paulo state, Brazil: II. quality of soil maps

The quality of semi-detailed (scale 1:100.000) soil maps and the utility of a taxonomically based legend were assessed by studying 33 apparently homogeneous fields with strongly weathered soils in two regions in São Paulo State: Araras and Assis. An independent data set of 395 auger sites was used to determine purity of soil mapping units and analysis of variance within and between mapping units and soil classification units. Twenty three soil profiles were studied in detail. The studied soil maps have a high purity for some legend criteria, such as B horizon type (> 90%) and soil texture class (> 80%). The purity for the "trophic character" (eutrophic, dystrophic, allic) was only 55% in Assis. It was 88% in Araras, where many soil units had been mapped as associations. In both regions, the base status of clay-textured soils was generally better than suggested by the maps. Analysis of variance showed that mapping was successful for "durable" soil characteristics such as clay content (> 80% of variance explained) and cation exchange capacity (≥ 50% of variance explained) of 0-20 and 60-80 cm layers. For soil characteristics that are easily modified by management, such as base saturation of the 0-20 cm layer, the maps had explained very little (< 15%) of the total variance in the study areas. Intermediate results were obtained for base saturation of the 60-80 cm layer (56% in Assis; 42% in Araras). Variance explained by taxonomic groupings that formed the basis for the legend of the soil maps was similar to, often even smaller than, variance explained by mapping units. The conclusion is that map boundaries have been very carefully located, but descriptions of mapping units could be improved. In future mappings, this could possibly be done at low cost by (a) bulk sampling to remove short range variation and enhance visualization of spatial patterns at distances > 100 m; (b) taking advantage of correlations between easily measured soil characteristics and chemical soil properties and, (c) unbending the link between legend criteria and a taxonomic system. The maps are well suited to obtain an impression of land suitability for high-input farming. Additional field work and data on former land use/management are necessary for the evaluation of chemical properties of surface horizons.

Spatial analysis of corresponding fingerprint features from match and close non-match populations

The development of statistical models for forensic fingerprint identification purposes has been the subject of increasing research attention in recent years. This can be partly seen as a response to a number of commentators who claim that the scientific basis for fingerprint identification has not been adequately demonstrated. In addition, key forensic identification bodies such as ENFSI [1] and IAI [2] have recently endorsed and acknowledged the potential benefits of using statistical models as an important tool in support of the fingerprint identification process within the ACE-V framework. In this paper, we introduce a new Likelihood Ratio (LR) model based on Support Vector Machines (SVMs) trained with features discovered via morphometric and spatial analyses of corresponding minutiae configurations for both match and close non-match populations often found in AFIS candidate lists. Computed LR values are derived from a probabilistic framework based on SVMs that discover the intrinsic spatial differences of match and close non-match populations. Lastly, experimentation performed on a set of over 120,000 publicly available fingerprint images (mostly sourced from the National Institute of Standards and Technology (NIST) datasets) and a distortion set of approximately 40,000 images, is presented, illustrating that the proposed LR model is reliably guiding towards the right proposition in the identification assessment of match and close non-match populations. Results further indicate that the proposed model is a promising tool for fingerprint practitioners to use for analysing the spatial consistency of corresponding minutiae configurations.

Large TCR diversity of virus-specific CD8 T cells provides the mechanistic basis for massive TCR renewal after antigen exposure.

Ex vivo analysis of virus-specific CD8 T cell populations by anchored PCR has shown that the CD8 TCR repertoire was less oligoclonal (seven to nine clonotypes per individual epitope) than previously thought. In the current study, TCR diversity was investigated by assessing both the overall TCR β-chain variable regions usage as well as the CDR3 regions in ex vivo-isolated CMV- and EBV-specific CD8 T cells from 27 healthy donors. The average number of clonotypes specific to most single viral epitopes comprised between 14 and 77. Changes in the CD8 TCR repertoire were also longitudinally assessed under conditions of HIV-1 chronic infection (i.e., in patients with suppressed virus replication and after treatment interruption and Ag re-exposure). The results showed that a large renewal (≤80%) of the TRB repertoire occurred after Ag re-exposure and was eventually associated with an increased T cell recognition functional avidity. These results demonstrate that the global CD8 TCR repertoire is much more diverse (≤9-fold) than previously estimated and provide the mechanistic basis for supporting massive repertoire renewal during chronic virus infection and Ag re-exposure.