Possible Applications of Neural Networks in Manufacturing

Summary form only given. An examination is made of the potential of neural networks and the impact of parallel processing in the design and operations of manufacturing systems. After an initial discussion on possible areas of application, an approach that integrates artificial intelligence, operations research, and neural networks for the solution of a scheduling problem is examine

Students Attitudes Toward A New Method For Preventing Loafing On The Group Project: The Team Activity Diary

The Team Activity Diary (TAD) is designed to prevent social loafing on the team project. This paper describes the TAD and reports on students’ perceptions of it. Although students appeared fairly indifferent to the TAD, 25% of the students indicated that it increased their contributions to the team project. Moreover, 16% of the students felt the TAD increased the contributions from some of their teammates.  The authors present recommendations for use of the TAD and offer suggestions for future researchers

Large‐scale hydro‐climatology of the terrestrial Arctic drainage system

The large‐scale hydro‐climatology of the terrestrial Arctic drainage system is examined, focusing on the period 1960 onward. Special attention is paid to the Ob, Yenisey, Lena, and Mackenzie watersheds, which provide the bulk of freshwater discharge to the Arctic Ocean. Station data are used to compile monthly gridded time series of gauge‐corrected precipitation (P). Gridded time series of precipitation minus evapotranspiration (P−ET) are calculated from the moisture flux convergence using NCEP reanalysis data. Estimates of ET are obtained as a residual. Runoff (R) is obtained from available discharge records. For long‐term water‐year means, P−ET for the Yenisey, Lena, and Mackenzie watersheds is 16–20% lower than the observed runoff. In the Ob watershed, the two values agree within 9%. Given the uncertainties in P−ET, we consider the atmospheric and surface water budgets to be reasonably closed. Compared to the other three basins, the mean runoff ratio (R/P) is lower in the Ob watershed, consistent with the high fraction of annual precipitation lost through ET. All basins exhibit summer maxima in P and minima in P−ET. Summer P−ET in the Ob watershed is negative due to high ET rates. For large domains in northern Eurasia, about 25% of July precipitation is associated with the recycling of water vapor evapotranspirated within each domain. This points to a significant effect of the land surface on the hydrologic regime. Variability in P and P−ET has generally clear associations with the regional atmospheric circulation. A strong link with the Urals trough is documented for the Ob. Relationships with indices of the Arctic Oscillation and other teleconnections are generally weak. Water‐year time series of runoff and P−ET are strongly correlated in the Lena watershed only, reflecting extensive permafrost. Cold‐season runoff has increased in the Yenisey and Lena watersheds. This is most pronounced in the Yenisey watershed, where runoff has also increased sharply in spring, decreased in summer, but has increased for the year as a whole. The mechanisms for these changes are not entirely clear. While they fundamentally relate to higher air temperatures, increased winter precipitation, and strong summer drying, we speculate links with changes in active layer thickness and thawing permafrost

Looking through the eyes of the powerful

Across four experiments, we test the idea that power decreases metastereotyping, and that this effect is mediated by reduced perspective taking. Metastereotypes refer to the beliefs that members of group A share about the stereotypes that members of specific outgroup B typically have about ingroup A. We propose that the dominant psychological orientation of the powerless is aimed at seeing how others see them. In an intergroup situation they are therefore inclined to activate and apply metastereotypes. In the first three experiments we consistently find that low power leads to more metastereotyping than high power and control (in Experiment 3). Specifically, we show this effect with three different manipulations of power, namely a role manipulation (Experiment 1), experiential priming (Experiment 2), and parafoveal priming (Experiment 3). In the fourth experiment we uncover the mediating role of perspective taking. Together these findings provide strong evidence that powerlessness leads to metastereotyping

A census of ρ\rho Oph candidate members from Gaia DR2

The Ophiuchus cloud complex is one of the best laboratories to study the earlier stages of the stellar and protoplanetary disc evolution. The wealth of accurate astrometric measurements contained in the Gaia Data Release 2 can be used to update the census of Ophiuchus member candidates. We seek to find potential new members of Ophiuchus and identify those surrounded by a circumstellar disc. We constructed a control sample composed of 188 bona fide Ophiuchus members. Using this sample as a reference we applied three different density-based machine learning clustering algorithms (DBSCAN, OPTICS, and HDBSCAN) to a sample drawn from the Gaia catalogue centred on the Ophiuchus cloud. The clustering analysis was applied in the five astrometric dimensions defined by the three-dimensional Cartesian space and the proper motions in right ascension and declination. The three clustering algorithms systematically identify a similar set of candidate members in a main cluster with astrometric properties consistent with those of the control sample. The increased flexibility of the OPTICS and HDBSCAN algorithms enable these methods to identify a secondary cluster. We constructed a common sample containing 391 member candidates including 166 new objects, which have not yet been discussed in the literature. By combining the Gaia data with 2MASS and WISE photometry, we built the spectral energy distributions from 0.5 to 22\microm for a subset of 48 objects and found a total of 41 discs, including 11 Class II and 1 Class III new discs. Density-based clustering algorithms are a promising tool to identify candidate members of star forming regions in large astrometric databases. If confirmed, the candidate members discussed in this work would represent an increment of roughly 40% of the current census of Ophiuchus.Comment: A&A, Accepted. Abridged abstrac

The Mr 30,000-33,000 major protein components of the lateral elements of synaptonemal complexes of the rat

Synaptonemal complexes (SCs) are intranuclear structures which are formed during meiotic prophase between homologous chromosomes. The SC consists of two protein-rich axes, either of which is found at the basis of one of the homologous chromosomes. These axes, called lateral elements (LEs), are connected along their entire length by so-called transverse filaments. Between and parallel to the LEs runs a third element, called central element. The assembly and disassembly of SCs take place in a period during which a number of important events takes place at the chromosomal level: condensation, pairing, recombination and segregation of homologous chromosomes. The possible involvement of the SC in these events is an importnat topic in the research program of our section. This thesis focusses on the possible function of the LE and its components (Chapter 1). The experimental work described in this thesis (Chapters 2-5) concerns the characterization of the LE-components with relative electrophoretic mobilities of 30,000 and 33,000 (the M r 30,000-33,000 components).The isolation of cDNAs encoding the M r 30,000-33,000 components is described in Chapter 2. The isolation took place by screening of an expression cDNA-library with an affinity-purified polyclonal antiserum. The largest cDNA, 2A4, encodes a protein with a predicted molecular mass of 29.7 kDa, which we have termed s ynaptonemal c omplex p rotein 3 (SCP3). A polyclonal antiserum raised against SCP3 recognizes only the M r 30,000-33,000 components on a westernblot of SC-protein and exhibits a similar immunological localisation as monoclonal antibodies and a polyclonal antiserum raised against the M r 30,000-33,000 components. The deduced amino acid sequence shows that SCP3 is a potential ATP-binding protein and that the C-terminal half of the protein is capable of forming an amphipaticα-helix. Moreover, part of the amino acid sequence exhibits considerable homology to the predicted protein products of two members of a gene familiy of X-linked lymphocyte-regulated ( Xlr ) genes.We conclude that cDNA 2A4 encodes at least one of the M r 30,000-33,000 components and that SCP3 is a major component of the LEs of the rat. We speculate that the homology between SCP3 and two products of Xlr genes might be connected to a function of both types of protein in processes which share the common purpose of blocking certain recombination events.The M r 30,000- and the 33,000 component are closely related according to their almost identical peptide maps and the fact that all isolated antibodies always recognize both proteins. A first step to elucidate the difference between these two components and the level at which such a difference arises is described in the addendum to Chapter 2. We conclude that the M r 30,000-33,000 components are probably encoded by a single gene and a single messenger RNA and that the difference between the two components arises during or after translation. Mechanisms by which this could be achieved are discussed. A practical problem which arises here is that N-terminal sequencing of the two components by means of standard techniques is not possible.When SC-protein is separated by means of two-dimensional gel electrophoresis (2D-electrophoresis) and the gel is subsequently blotted and the blot used for immunological detection of the M r 30,000-33,000 components, a large number of variants, differing in isoelectric point and relative electrophoretic mobility can be discerned. In Chapter 3 experiments are described which were performed to determine (i) the nature of the differences between the variants and (ii) possible changes in the observed pattern on 2D-gels during subsequent stages of meiotic prophase. We conclude that differences in the number of attached phosphate groups are largely responsible for the existence of different variants of the M r 30,000 as well as the M r 33,000 component. Moreover, we observed a change in the phosphorylation pattern between early- and midpachytene, probably because of the addition of one phosphate group to all variants. We speculate that the phosphorylation pattern observed as early as zygotene is the result of the action of a kinase which responds to DNA-damage.The presence of the LEs at the bases of the chromatin of the homologous chromosomes prompted us to investigate whether points of contact exist between LEs and the chromatin, and if so, which LE-components and DNA-sequences are involved (Chapter 4). Based on crosslinking experiments in vivo of chromatin from mouse spermatocytes, we assumed that the M r 30,000-33,000 components are bound to DNA or at least associated with DNA. By immunoprecipitation of protein-DNA complexes, obtained after crosslinking in vivo of mouse spermatocytes, with antibodies raised against the M r 30,000-33,000 components as well as against isolated SCs, a region was identified within a 120 kbp gene cluster as a SC - a ssociated r egion (SCAR). This SCAR colocalizes with a so-called 'matrix attachment region' (MAR). We also developed a method by which specific binding of DNA-fragments to the SC can be tested in vitro . By means of this method we show that MARs from different organisms bind specifically to rat SCs. We conclude that the organisation of the chromatin during meiotic prophase shows a certain similarity to those during mitosis and interphase.After it was determined that the M r 30,000-33,000 components are probably bound to DNA in vivo , we have further analysed the possible DNA-binding of these proteins as well as SCP3 in vitro (Chapter 5). Because of the insolubility of SCP3 in aqueous solutions, these studies were carried out by means of the Southwestern blotting technique. We conclude that SCP3 binds to DNA in vitro and shows a preference for single-stranded DNA. From a comparison of different single-stranded DNA substrates we conclude that SCP3 probably favours binding to single-stranded DNA which adopts a spatial conformation caused by intra- or intermolecular interactions. In similar experiments the M r 30,000-33,000 components also exhibit a preference for single-stranded DNA, although the variants which caary the most phosphate residues show no detectable DNA-binding at all. Based on the assumption that in the situation in vivo the M r 30,000-33,000 components would exhibit a similar type of DNA-binding as in vitro , we speculate on the (temporal) existence of single-stranded DNA during meiotic prophase.Finally, I present a summary on what is known about the M r 30,000-33,000 components at the beginning of the general discussion (Chapter 6). Then I discuss a model which describes the chromatin organization during meiotic prophase, in which I particularly point at the modifications which, starting from a general organization pattern, are necessary for the proper progress of the processes of pairing, recombination and segregation of homologous chromosomes. Within this model I discuss the possible involvement of components of the SC. After that I focuss on the function of the M r 30,000-33,000 components in this model. I propose that the M r 30,000-33,000 components play a role in the structural organization of the chromosomes, in such a manner that recombination between sister chromatids is inhibited temporarily and cohesion between sister chromatids is maintained as long as this is needed.</p

Invisible water, visible impact: How unsustainable groundwater use challenges sustainability of Indian agriculture under climate change

India is one of the world’s largest food producers, making the sustainability of its agricultural system of global significance. Groundwater irrigation underpins India’s agriculture, currently boosting crop production by enough to feed 170 million people. Groundwater overexploitation has led to drastic declines in groundwater levels, threatening to push this vital resource out of reach for millions of small-scale farmers who are the backbone of India’s food security. Historically, losing access to groundwater has decreased agricultural production and increased poverty. We take a multidisciplinary approach to assess climate change challenges facing India’s agricultural system, and to assess the effectiveness of large-scale water infrastructure projects designed to meet these challenges. We find that even in areas that experience climate change induced precipitation increases, expansion of irrigated agriculture will require increasing amounts of unsustainable groundwater. The large proposed national river linking project has limited capacity to alleviate groundwater stress. Thus, without intervention, poverty and food insecurity in rural India is likely to worsen