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Marion King Hubbert (1903-1989) is a geophysicist mostly known for his work on the availability of oil resources (known as “peak oil” theory). But Hubbert was also a political theorist and activist of the Technocracy Movement, a political movement mainly active in the United States in the 1930s. This movement is characterized by a physical approach to economic phenomena and by its advocacy in favor of a planning of the entire economy under the control of engineers. Hubbert produced the most systematized account of technocratic thought in a book entitled Technocracy Study Course, which was used in the scientific and political training of Technocracy activists in an organization co-founded by him. This article examines how this book questions the boundary between economics and natural sciences by making a distinction between, on one hand, economic facts which constitute a transformation of energy and resources and are thus ruled by the laws of physics; and on the other hand, monetary phenomena, which are ruled by human conventions. We give a commentary of Hubbert’s attempt to build a critique of market economy based on a non-metaphorical use of physics, and explain what brings him to defend an energy-based planning of the economy. We claim that these elements make Hubbert’s work relevant to the history of bio-physical approaches in economics.

Study Question: Can human theca cells (TCs) be differentiated in vitro?Summary Answer: It is possible to differentiate human TCs in vitro using a medium supplemented with growth factors and hormones.What Is Known Already: There are very few studies on the origin of TCs in mammalian ovaries. Precursor TCs have been described in neonatal mice ovaries, which can differentiate into TCs under the influence of factors from oocytes and granulosa cells (GCs). On the other hand, studies in large animal models have reported that stromal cells (SCs) isolated from the cortical ovarian layer can also differentiate into TCs.Study Design, Size, Duration: After obtaining informed consent, ovarian biopsies were taken from eight menopausal women (53-74 years of age) undergoing laparoscopic surgery for gynecologic disease not related to the ovaries. SCs were isolated from the ovarian cortex and in vitro cultured for 8 days in basic medium (BM) (G1), enriched with growth factors, FSH and LH in plastic (G2) or collagen substrate without (G3) or with (G4) a GC line.Participants/materials, Setting, Methods: To confirm TC differentiation, relative mRNA levels for LH receptor (Lhr), steroidogenic acute regulatory protein (Star), cholesterol side-chain cleavage enzyme (Cyp11a1), cytochrome P450 17A1 (Cyp17a1), hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 (Hsd3b1) and hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 2 (Hsd3b2) were assessed. Immunohistochemistry was also performed for their protein detection and a specific marker was identified for TCs (aminopeptidase-N, CD13), as were markers for theca and small luteal cells (dipeptidyl peptidase IV (CD26) and Notch homolog 1, translocation-associated (NOTCH1)). Finally, we analyzed cell ultrastructure before (Day 0) and after in vitro culture (Day 8), and dehydroepiandrosterone (DHEA) and progesterone levels in the medium using transmission electron microscopy (TEM) and ELISA, respectively.Main Results and the Role Of Chance: Results obtained from qPCR showed a significant increase (P < 0.05) in mRNA levels of Lhr in F2 (floating cells in G2) and G4, Cyp17a1 in G1 and F1 (floating cells in G1) and Hsd3b2 in G1, G2, G3 and G4. Immunohistochemistry confirmed expression of each enzyme involved in the steroidogenic pathway at the protein stage. However, apart from G1, all other groups exhibited a significant (P < 0.05) rise in the number of CD13-positive cells. There was also a significant increase (P < 0.05) in NOTCH1-positive cells in G3 and G4. Ultrastructure analyses by TEM showed a distinct difference between groups and also versus Day 0. A linear trend with time revealed a significant gain (q < 0.001) in DHEA concentrations in the medium during the culture period in G1, G2, G3 and G4. It also demonstrated a statistical increase (q < 0.001) in G2, G3 and G4 groups, but G1 remained the same throughout culture in terms of progesterone levels.Large Scale Data: N/A.Limitations, Reasons For Caution: Shorter periods of in vitro culture (e.g. 2, 4 and 6 days) could have led to increased concentrations of differentiated TCs in G2, G3 and G4. In addition, a group of cells cultured in BM and accompanied by COV434 cells would be necessary to understand their role in the differentiation process. Finally, while our results demonstrate that TCs can be differentiated in vitro from cells isolated from the cortical layer of postmenopausal ovaries, we do not know if these cells are differentiated from a subpopulation of precursor TCs present in ovarian cortex or ovarian SCs in general. It is therefore necessary to identify specific markers for precursor TCs in human ovaries to understand the origin of these cells.Wider Implications Of the Findings: This is a promising step toward understanding TC ontogenesis in the human ovary. Moreover, in vitro-generated human TCs can be used for studies on drug screening, as well as to understand TC-associated pathologies, such as androgen-secreting tumors and polycystic ovary syndrome.Study Funding/competing Interest(s): This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (FNRS) (C.A.A. is an FRS-FNRS Research Associate; grant MIS #F4535 16 awarded to C.A.A.; grant 5/4/150/5 awarded to M.M.D.; grant ASP-RE314 awarded to P.A.) and Foundation Against Cancer (grant 2018-042 awarded to A.C.). The authors declare no competing interests. [ABSTRACT FROM AUTHOR]

Many genetic risk factors have been identified for causing venous thromboembolism (VTE). Most of them affect the function of natural anticoagulant pathways, particularly the protein C system, although recent studies suggest a role of components of the hematopoietic pathway in the etiology of venous thrombosis. In this case-control study, we aimed to determine the frequency of prothrombin G20210A and factor V Leiden (FVL) G1691A polymorphisms and protein C, protein S, and antithrombin III deficiencies in the East Algerian population and to investigate whether these genetic factors are associated with VTE. On the other hand, our study tends to evaluate the status of JAK2V617F and calreticulin (CALR) mutations among these cases. The participants consisted of 121 cases with VTE and 146 healthy controls. Polymorphisms of FVL G1691A and prothrombin G20210A were genotyped by polymerase chain reaction (PCR) restriction fragment length polymorphism. JAK2-V617F and calreticulin mutations were analyzed by quantitative PCR and PCR followed by capillary electrophoresis sequencing, respectively. Protein C, protein S, and antithrombin levels were determined and then hereditary deficiencies were identified. Of all cases and controls, none was a carrier of the antithrombin III deficiency, prothrombin gene G20210A, and CALR mutations. Only 1 case reported having a positive JAK2 mutation (mutant allele burden was 15%). The FVL mutation (GA/AA) was found in 14 (11.6%) cases and 2 (1.4%) controls and it was significantly different between both the groups (P = .001). Deficiencies of protein S and protein C were detected in 17 (18.8%) cases. The univariate analysis resulted in a significant impact of FVL (odds ratio [OR] = 9.4, 95% confidence interval [CI] = 2.1-42.3; P = .003) and of protein S deficiency (OR = 16.9, 95% CI =2.1-132.8, P = .007) on the VTE status. Both factors stayed significant after adjustment for sex and age. The OR of the protein C deficiency was slightly elevated (OR = 6.4, 95% CI = 0.7-55.5), but it did not reach the level of statistical significance (P = .091), and it was therefore not considered as a risk factor. In conclusion, coagulant factor V gene G1691A mutation and protein S deficiency constitute important genetic risk factors in patients with VTE in Eastern Algeria. The somatic mutation of JAK2 V617F and CALR mutations are less frequent causes of VTE, thus routine testing for these mutations is not recommended. [ABSTRACT FROM AUTHOR]

In the present paper, we consider nonlinear PT-symmetric dimers and trimers (more generally, oligomers) embedded within a linear Schrödinger lattice. We examine the stationary states of such chains in the form of plane waves, and analytically compute their reflection and transmission coefficients through the nonlinear PT symmetric oligomer, as well as the corresponding rectification factors which clearly illustrate the asymmetry between left and right propagation in such systems. We examine not only the existence but also the dynamical stability of the plane wave states and interestingly find them to be unstable except in the vicinity of the linear limit. Lastly, we generalize our numerical considerations to themore physically relevant case of Gaussian initial wavepackets and confirm that the asymmetry in the transmission properties persists in the case of such wavepackets, as well. The role of potential asymmetries in the nonlinearity or in the gain/loss pattern is also considered. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present paper was to investigate the efficiency of polyether polyol as shrinkage-reducing admixture on pastes and mortars prepared with calcium sulfoaluminate cement (CSA). CSA was prepared by mixing CSA clinker and re-crystallized gypsum in different proportions. Three types of polyether polyol were added at a dosage of 1.5wt% of CSA when hydrating pure pastes and standard mortars. The engineering properties of mortars (compressive strength, drying shrinkage) and the microstructure of pastes were investigated. The results show that polyol reduces drying shrinkage of CSA-based mortars without affecting the nature of hydrates formed. The effect of polyol mainly depends on its molecular weight. [Copyright &y& Elsevier]

Abstract: The development of cement-based screed unbound to its support is still limited because of the curling that occurs at the corners and perimeter of the screed. This phenomenon is mainly due to the moisture gradient that appears within the thickness of the screed: the upper surface dries and shrinks, whereas lower regions dry less and stay wetter. This paper demonstrates this phenomenon can be mitigated through the use of calcium sulfoaluminate cement instead of ordinary Portland cement. Experiments utilizing an original, specially designed device, show that curling is 3.5 times lower when calcium sulfoaluminate cement is used compared to ordinary Portland cement. The moisture gradient within the thickness of the screed is also lower. A model based on simplified poroelasticity theory describes both fluid transfer and hydro-mechanical coupling. The comparison between experimental and calculated results shows that the model gives a good estimation of the kinetics of the mass loss, and that the numerical simulation is an effective tool to predict curling due to drying. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a laboratory study undertaken to examine the treatment of demolition waste containing calcium sulfate by means of calcium sulfoaluminate clinker (CSA). The quantity of CSA necessary to entirely consume calcium sulfate was determined. Using infrared spectrometry analysis and X-ray diffraction, it was shown that calcium sulfate was entirely consumed when the ratio between CSA and calcium sulfate was 4. Standard sand was polluted by 4% calcium sulfate. Two solutions were investigated: [•] either global treatment of sand by CSA, [•] or immobilization of calcium sulfate by CSA, followed by the introduction of this milled mixture in standard sand. Regardless of the type of treatment, swelling was almost stabilized after 28 days of immersion in water. [Copyright &y& Elsevier]

This paper presents four innovative utilizations of calcium sulfoaluminate (CSA) cement:–development of concrete with high early strength: 40 MPa, 6 h after its preparation, and higher than 55 MPa after 24 h,–design of self-leveling screed with limited curling, when unbonded to its support,–design of self-leveling topping mortar presenting the following properties: time of workability higher than 30 min, set within 75 min, and low drying shrinkage (<250μm/m).–glass-fiber-reinforced cement (GFRC) composites that can be demolded 4 h after casting and present high ductility and durability after aging in different weathering conditions. [Copyright &y& Elsevier]

Every year in EU nations, it is estimated that 3 million tonnes of automotive shredder residue (ASR) are generated. Half of the ASR is composed of rubber, textiles and plastics, which can be either transformed into alternative fuel or recycled. The second half, which is landfilled, is incombustible and has not yet been valorized.This waste contains 30% organic matter, as well as inorganic compounds such as quartz, calcite, magnetite, hematite, and anhydrite. It is also very rich in zinc (1–3.5%) and lead (0.7–3.3%). These elements are powerful retarders of ordinary Portland cement. For this reason, two ways of processing of this waste have been investigated: (1) transformation into aggregates after a thermal treatment followed by a chemical treatment or (2) directly into concrete with the use of calcium sulfoaluminate cement.This second way is especially very interesting for engineers and scientists. As established by leaching tests, zinc and lead are integrated and fixed in the structure of ettringite, the main hydration product of calcium sulfoaluminate cement. Therefore, it is possible to produce concrete for some applications including road construction from this currently landfilled “waste” (i.e., the ASR is shown to be useful recyclable material that can be converted into an environmentally friendly “green” concrete). [Copyright &y& Elsevier]

• We study solitary wave solutions to the focusing nonlinear cubic Schrödinger equation on the surface of a torus. • We identify bright-solitary-waves localized in both angular directions. • We identify bright-solitary-waves localized in one direction and homogeneous in the other. • The stability properties of the waves are examined and one family is found to be spectrally stable. • Dynamics can give rise to collapse or to oscillations around the spectrally stable solution family. Motivated by recent developments in the realm of matter waves, we explore the potential of creating solitary waves on the surface of a torus. This is an intriguing perspective due to the role of curvature in the shape and dynamics of the coherent structures. We find different families of bright solitary waves for attractive nonlinearities including ones localized in both angular directions, as well as waves localized in one direction and homogeneous in the other. The waves localized in both angular directions have also been partitioned into two types: those whose magnitude decays to zero and those who do not. The stability properties of the waves are examined and one family is found to be spectrally stable in a suitable parametric regime while most are spectrally unstable, a feature that we comment on. Finally, the nature of the ensuing nonlinear dynamics is touched upon. [ABSTRACT FROM AUTHOR]

Abstract Background The standard approach for preprocessing spotted microarray data is to subtract the local background intensity from the spot foreground intensity, to perform a log2 transformation and to normalize the data with a global median or a lowess normalization. Although well motivated, standard approaches for background correction and for transformation have been widely criticized because they produce high variance at low intensities. Whereas various alternatives to the standard background correction methods and to log2 transformation were proposed, impacts of both successive preprocessing steps were not compared in an objective way. Results In this study, we assessed the impact of eight preprocessing methods combining four background correction methods and two transformations (the log2 and the glog), by using data from the MAQC study. The current results indicate that most preprocessing methods produce fold-change compression at low intensities. Fold-change compression was minimized using the Standard and the Edwards background correction methods coupled with a log2 transformation. The drawback of both methods is a high variance at low intensities which consequently produced poor estimations of the p-values. On the other hand, effective stabilization of the variance as well as better estimations of the p-values were observed after the glog transformation. Conclusion As both fold-change magnitudes and p-values are important in the context of microarray class comparison studies, we therefore recommend to combine the Edwards correction with a hybrid transformation method that uses the log2 transformation to estimate fold-change magnitudes and the glog transformation to estimate p-values.

Abstract Background The structural genomics centers provide hundreds of protein structures of unknown function. Therefore, developing methods enabling the determination of a protein function automatically is imperative. The determination of a protein function can be achieved by studying the network of its physical interactions. In this context, identifying a potential binding site between proteins is of primary interest. In the literature, methods for predicting a potential binding site location generally are based on classification tools. The aim of this paper is to show that regression tools are more efficient than classification tools for patches based binding site predictors. For this purpose, we developed a patches based binding site localization method usable with either regression or classification tools. Results We compared predictive performances of regression tools with performances of machine learning classifiers. Using leave-one-out cross-validation, we showed that regression tools provide better predictions than classification ones. Among regression tools, Multilayer Perceptron ranked highest in the quality of predictions. We compared also the predictive performance of our patches based method using Multilayer Perceptron with the performance of three other methods usable through a web server. Our method performed similarly to the other methods. Conclusion Regression is more efficient than classification when applied to our binding site localization method. When it is possible, using regression instead of classification for other existing binding site predictors will probably improve results. Furthermore, the method presented in this work is flexible because the size of the predicted binding site is adjustable. This adaptability is useful when either false positive or negative rates have to be limited.

We consider the eigenvalue problem for one-dimensional linear Schrödinger lattices (tight-binding) with an embedded few-sites linear or nonlinear, Hamiltonian or non-conservative defect (an oligomer). Such a problem arises when considering scattering states in the presence of (generally complex) impurities as well as in the stability analysis of nonlinear waves. We describe a general approach based on a matching of solutions of the linear portions of the lattice at the location of the oligomer defect. As specific examples, we discuss both linear and nonlinear, Hamiltonian and PT-symmetric dimers and trimers. In the linear case, this approach provides us a handle for semi-analytically computing the spectrum [this amounts to the solution of a polynomial equation]. In the nonlinear case, it enables the computation of the linearization spectrum around the stationary solutions. The calculations showcase the oscillatory instabilities that strongly nonlinear states typically manifest. [ABSTRACT FROM AUTHOR]

Abstract: The water resistance of plaster of Paris is limited due to the high solubility of calcium sulphate hemihydrate. In order to improve this resistance, calcium sulphoaluminate clinker was added to plaster at different contents: 30, 50, and 70%. Mortars were cast using these new binders and subjected to the Soxhlet extraction test. The presence of calcium sulphoaluminate clinker considerably reduced the quantity of sulphate extracted per day and after 5days: from 78.9% to 89.1%. The analysis of microstructure showed the stability of ettringite during the leaching test and the refinement of the porosity. [Copyright &y& Elsevier]

Abstract: Materials with a cement matrix classically present early-age volume variations (shrinkage and/or swelling). This intrinsic early-age behavior strongly influences the length of time the buildings and structures will last because of the micro-cracking and cracking that results from it. One explanation for the macroscopic shrinkage is the presence of pore pressure in the porous medium. In this study, fine modeling of the coupling mechanism behind these internal strains is proposed. The chemical reaction associated with hydration is considered as the main force behind the hydric and mechanical evolutions in an endogenous configuration. Thus, the influence of chemical contraction, porosity, pore-size distribution and pore pressure are central to the study in the light of the numerical and experimental results obtained. A self-leveling layer of mortar of sulfo-aluminous concrete base was used. [Copyright &y& Elsevier]

Abstract: Phosphogypsum (calcium sulfate) is a naturally occurring part of the process of creating phosphoric acid (H3PO4), an essential component of many modern fertilizers. For every tonne of phosphoric acid made, from the reaction of phosphate rock with acid, commonly sulfuric acid, about 3t of phosphogypsum are created. There are three options for managing phosphogypsum: (i) disposal or dumping, (ii) stacking, (iii) use-in, for example, agriculture, construction, or landfill. This paper presents the valorization of two Tunisian phosphogypsums (referred as G and S) in calcium sulfoaluminate cement in the following proportions: 70% phosphogypsum–30% calcium sulfoaluminate clinker. The use of sample G leads to the production of a hydraulic binder which means that it is not destroyed when immersed in water. The binder including sample S performs very well when cured in air but is not resistant in water. Formation of massive ettringite in a rigid body leads to cracking and strength loss. [Copyright &y& Elsevier]

Abstract: Early-age volume variations of self-leveling mortar of sulfo-aluminous cement base are evaluated in an endogenous configuration and during the drying process. Two displacement measuring techniques are used: a classical method using displacement sensors and a more original one using digital 3-D image correlation. The latter technique reveals itself to be very useful in measuring shrinkage and swelling as soon as the screed is poured. An advanced hydromechanical modelization confirms on the one hand the amplitude of the deformations measured by digital 3-D image correlation and underlines on the other the importance of Young''s modulus concerning this amplitude. [Copyright &y& Elsevier]

Dilute-gas Bose-Einstein condensates are an exceptionally versatile test bed for the investigation of novel solitonic structures. While matter-wave solitons in one- and two-component systems have been the focus of intense research efforts, an extension to three components has never been attempted in experiments. Here, we experimentally demonstrate the existence of robust dark-bright-bright (DBB) and dark-dark-bright solitons in a multicomponent F=1 condensate. We observe lifetimes on the order of hundreds of milliseconds for these structures. Our theoretical analysis, based on a multiscale expansion method, shows that small-amplitude solitons of these types obey universal long-short wave resonant interaction models, namely, Yajima-Oikawa systems. Our experimental and analytical findings are corroborated by direct numerical simulations highlighting the persistence of, e.g., the DBB soliton states, as well as their robust oscillations in the trap. [ABSTRACT FROM AUTHOR]