Power-law weighted networks from local attachments

This letter introduces a mechanism for constructing, through a process of distributed decision-making, substrates for the study of collective dynamics on extended power-law weighted networks with both a desired scaling exponent and a fixed clustering coefficient. The analytical results show that the connectivity distribution converges to the scaling behavior often found in social and engineering systems. To illustrate the approach of the proposed framework we generate network substrates that resemble steady state properties of the empirical citation distributions of (i) publications indexed by the Institute for Scientific Information from 1981 to 1997; (ii) patents granted by the U.S. Patent and Trademark Office from 1975 to 1999; and (iii) opinions written by the Supreme Court and the cases they cite from 1754 to 2002.Comment: 18 pages, 3 figures; Proceedings of the IEEE Conference on Decision and Control and the European Control Conference, Orlando, FL, Dec. 2011; Added references; We modified the model in order to take into account extended power-law distributions which better fit to the citations data sets; Added proofs of theorems; Shorten version; Updated plo

Construction and application of a questionnaire for the social scientific investigation of environmental noise effects

A social psychological questionnair has been developed to study the effects of environmental noise and was applied to 636 people living in 19 different areas of Hamburg. The theoretical foundations and the statistical means employed in its development are described. Four main reactions to noise are isolated statistically, and it is determined that these are moderated by several intervening variables, chief of which are coping capacity for noise, the perceived dangerousness of the noise souce, other daily loads and the individual's liability

Acetate, lactate, propionate, and isobutyrate as electron donors for iron and sulfate reduction in Arctic marine sediments, Svalbard

The contribution of volatile fatty acids (VFA) as e–-donors for anaerobic terminal oxidation of organic carbon through iron and sulfate reduction was studied in Arctic fjord sediment. Dissolved inorganic carbon, Fe2+, VFA concentrations, and sulfate reduction were monitored in slurries from the oxidized (0–2 cm) and the reduced (5–9 cm) zone. In the 0–2 cm layer, 2/3 of the mineralization could be attributed to sulfate reduction and 1/3 to iron reduction. In the 5–9 cm layer, sulfate reduction was the sole mineralization process. Acetate and lactate turnover rates were measured by radiotracer. Inhibition of sulfate reduction with selenate resulted in the accumulation of acetate, propionate, and isobutyrate. The acetate turnover rates determined by radiotracer and accumulation after inhibition were similar. VFA turnover accounted for 21% and 52% of the mineralization through sulfate reduction in the 0–2 and 5–9 cm layer, respectively. Acetate and lactate turnover in the inhibited 0–2 cm slurry was attributed to iron reduction and accounted for 10% and 2% of the iron reduction. Therefore, 88% and 79% of the iron and sulfate reduction in the 0–2 cm layer, respectively, must be fueled by alternative e−-donors. The accumulation of VFA in the selenate–inhibited 0–2 cm slurry did not enhance iron reduction, indicating that iron reducers were not limited by VFA availability

Planning When Goals Change: A Moving Target Search Approach

International audienceDevising intelligent robots or agents that interact with humans is a major challenge for artificial intelligence. In such contexts, agents must constantly adapt their decisions according to human activities and modify their goals. In this paper, we tackle this problem by introducing a novel planning approach, called Moving Goal Planning (MGP), to adapt plans to goal evolutions. This planning algorithm draws inspiration from Moving Target Search (MTS) algorithms. In order to limit the number of search iterations and to improve its efficiency, MGP delays as much as possible triggering new searches when the goal changes over time. To this purpose, MGP uses two strategies: Open Check (OC) that checks if the new goal is still in the current search tree and Plan Follow (PF) that estimates whether executing actions of the current plan brings MGP closer to the new goal. Moreover, MGP uses a parsimonious strategy to update incrementally the search tree at each new search that reduces the number of calls to the heuristic function and speeds up the search. Finally, we show evaluation results that demonstrate the effectiveness of our approach

LaMer's 1950 model of particle formation: a review and critical analysis of its classical nucleation and fluctuation theory basis, of competing models and mechanisms for phase-changes and particle formation, and then of its application to silver halide, semiconductor, metal, and metal-oxide nanoparticles

A review is presented of the pioneering 1950 model (V. K. LaMer, R. H. Dinegar, Theory, Production and Mechanism of Formation of Monodispersed Hydrosols, J. Am. Chem. Soc., 1950, 72, 4847-4854) of how monodisperse particles might possibly be formed. The review begins with a look at the basis of the 1950 model in fluctuation and classical nucleation theories. Presented next are the competing phase-change models and then also chemical mechanisms for particle formation available since the 1950 paper, including a little-cited nucleation mechanism that LaMer insightfully wrote in 1952. This review then takes a critical look at the 164 (similar to 8%) of the 192 total (similar to 10%) out of the 1953 papers (as of March 2019) that cite the 1950 model while also providing at least some discussion, analysis, or additional data bearing on the 1950 model postulating "effectively infinite nucleation" and "diffusion-controlled growth". (The other 28 papers out of the 192 total papers describe S-n sol formation were covered in an earlier, Part I review that is cited.) Those 164 papers are broken down into five tables provided in the Supporting Information and are then covered in separate sections in the main text: first 13 papers on silver halide nanoparticles (Table S1) where the single best evidence in support of the 1950 model has been thought to exist; 26 papers on semiconductor nanoparticles (Table S2); then 69 papers on transition-metal nanoparticle formation (Table S3); 39 papers on oxide-based nanoparticles (Table S4); and 17 papers presenting alternative models or mechanisms in comparison to the 1950 model (Table S5). The review focuses on answering the critical question of: do the concepts of "burst/instantaneous nucleation" and "diffusion-controlled growth" have sound, compelling experimental support in the 70 years since the model first appeared and in the 164 papers examined more closely that do more than just cite the 1950 model? A Conclusions section listing sixteen bullet points is provided, as is a final section entitled "A Look Towards the Future" that discusses evolving areas and suggested emphasis points for facilitating future research in particle formation kinetics, mechanism and associated particle syntheses

Intensified and protective CD4+ T cell immunity in mice with anti-dendritic cell HIV gag fusion antibody vaccine

Current human immunodeficiency virus (HIV) vaccine approaches emphasize prime boost strategies comprising multiple doses of DNA vaccine and recombinant viral vectors. We are developing a protein-based approach that directly harnesses principles for generating T cell immunity. Vaccine is delivered to maturing dendritic cells in lymphoid tissue by engineering protein antigen into an antibody to DEC-205, a receptor for antigen presentation. Here we characterize the CD4+ T cell immune response to HIV gag and compare efficacy with other vaccine strategies in a single dose. DEC-205-targeted HIV gag p24 or p41 induces stronger CD4+ T cell immunity relative to high doses of gag protein, HIV gag plasmid DNA, or recombinant adenovirus-gag. High frequencies of interferon (IFN)-γ- and interleukin 2-producing CD4 + T cells are elicited, including double cytokine-producing cells. In addition, the response is broad because the primed mice respond to an array of peptides in different major histocompatibility complex haplotypes. Long-lived T cell memory is observed. After subcutaneous vaccination, CD4+ and IFN-γ-dependent protection develops to a challenge with recombinant vaccinia-gag virus at a mucosal surface, the airway. We suggest that a DEC-targeted vaccine, in part because of an unusually strong and protective CD4+ T cell response, will improve vaccine efficacy as a stand-alone approach or with other modalities

Prognosis after high-dose chemotherapy followed by autologous stem-cell transplantation as first-line treatment in primary CNS lymphoma—a long-term follow-up study

Background High-dose chemotherapy followed by autologous stem-cell transplantation (HCT-ASCT) is a promising approach in eligible patients with primary central nervous system lymphoma (PCNSL). We report long-term data of patients who were treated according to HCT-ASCT containing protocols. Patients and methods We analyzed survival and relapse rates in 43 (<67 years) immunocompetent patients with newly diagnosed PCNSL being treated according to two different high-dose methotrexate-based protocols followed by high-dose carmustine/thiotepa (BCNU/TT) plus ASCT (±whole brain irradiation). Analysis was conducted for all patients (intention-to-treat) and those patients who actually received HCT-ASCT (per-protocol). Results Thirty-four patients achieved complete remission, of those 12 relapsed (35%), while 6 of them relapsed 5 years after diagnosis. After a median follow-up of 120 months, median overall survival (OS) was reached after 104 months. Two- and 5-year OS was 81% and 70% and 2- and 5-year event-free survival (EFS) was 81% and 67%, respectively. In per-protocol analysis (N=34), 5-year OS and EFS was 82% and 79%, respectively. HCT-ASCT associated related mortality was not observed. Conclusions Sequential high-dose MTX containing chemotherapy followed by high-dose carmustine/thiotepa plus ASCT (±whole brain irradiation) is safe and leads to high survival rates in eligible patients with newly diagnosed PCNS

Network synchronization of groups

In this paper we study synchronized motions in complex networks in which there are distinct groups of nodes where the dynamical systems on each node within a group are the same but are different for nodes in different groups. Both continuous time and discrete time systems are considered. We initially focus on the case where two groups are present and the network has bipartite topology (i.e., links exist between nodes in different groups but not between nodes in the same group). We also show that group synchronous motions are compatible with more general network topologies, where there are also connections within the groups

Sensitivity analysis and calibration of a soil carbon model (SoilGen2) in two contrasting loess forest soils

To accurately estimate past terrestrial carbon pools is the key to understanding the global carbon cycle and its relationship with the climate system. SoilGen2 is a useful tool to obtain aspects of soil properties (including carbon content) by simulating soil formation processes; thus it offers an opportunity for both past soil carbon pool reconstruction and future carbon pool prediction. In order to apply it to various environmental conditions, parameters related to carbon cycle process in SoilGen2 are calibrated based on six soil pedons from two typical loess deposition regions (Belgium and China). Sensitivity analysis using the Morris method shows that decomposition rate of humus (&lt;i&gt;k&lt;/i&gt;&lt;sub&gt;HUM&lt;/sub&gt;), fraction of incoming plant material as leaf litter (fr&lt;sub&gt;ecto&lt;/sub&gt;) and decomposition rate of resistant plant material (&lt;i&gt;k&lt;/i&gt;&lt;sub&gt;RPM&lt;/sub&gt;) are the three most sensitive parameters that would cause the greatest uncertainty in simulated change of soil organic carbon in both regions. According to the principle of minimizing the difference between simulated and measured organic carbon by comparing quality indices, the suited values of &lt;i&gt;k&lt;/i&gt;&lt;sub&gt;HUM&lt;/sub&gt;, (fr&lt;sub&gt;ecto&lt;/sub&gt; and &lt;i&gt;k&lt;/i&gt;&lt;sub&gt;RPM&lt;/sub&gt; in the model are deduced step by step and validated for independent soil pedons. The difference of calibrated parameters between Belgium and China may be attributed to their different vegetation types and climate conditions. This calibrated model allows more accurate simulation of carbon change in the whole pedon and has potential for future modeling of carbon cycle over long timescales