Indirect Products Research Articles

Photolysis- and Dissolved Organic Matter-Induced Toxicity of Triclocarban to Daphnia magna

Triclocarban (TCC) is a common antimicrobial compound used in soaps and other household products and is found globally in many surface waters. This study investigated the acute toxicity of TCC and its photolyzed products to Daphnia magna using 50% 96-h lethal concentration (LC50) tests. The effects of dissolved organic matter (DOM) on the toxicity of TCC photoproducts to D. magna were also studied. Direct photolysis of TCC formed photoproducts that were significantly less toxic (LC50 value of 2.67 ± 0.6 μM) than the parent TCC compound (LC50 value of 0.087 ± 0.3 μM). In contrast, the indirect photolysis of TCC in the presence of DOM produced photoproducts that were significantly more toxic (LC50 value of 0.032 ± 0.015 μM). Chlorinated anilines and isocyanates, identified by mass spectrometry, were formed in the presence of DOM as indirect photolysis products of TCC and were shown to be partially responsible for the observed toxicity.

Changes in ecosystem services associated with planting structures of cropland: A case study in Minle County in China

The cropland ecosystem provides essential direct and indirect products and services to mankind such as food, fiber, biodiversity and soil conservation. A change of crop planting structure can change the ecosystem services of cropland by affecting land use type. In recent years, under the influence of regional comparative advantage and consumer demand changes, the crop planting structure in China has changed rapidly. However, there is still a lack of deep understanding on the effect of such a change in planting structure on the ecosystem services of cropland. Therefore, this research selected Minle County in the Heihe River Basin, which has small scattered croplands and a complex planting structure, as a study area. Based on the key time phase and optimal threshold of the normalized difference vegetation index (NDVI) data of the Thematic Mapper and Enhanced Thematic Mapper Plus (TM/ETM+) images, this study used the decision tree algorithm to classify and extract the crop planting structure in Minle County in 2007 and 2012 and to analyze the changes in its temporal and spatial patterns. Then, the market value method was adopted to estimate the effect of the change in crop planting structure on the ecosystem services of the cropland. From 2007 to 2012, the planting area of corn and rapeseed in Minle County increased by 5.86 × 103 ha and 5.10 × 103 ha, respectively. Conversely, the planting area of wheat and barley was reduced by 3.26 × 103 ha and 6.34 × 103 ha, respectively. These changes directly caused the increase of the ecosystem services value of corn and rapeseed by 1062.82 × 104 USD and 842.54 × 104 USD, respectively. The resulting reduction in the ecosystem services value of wheat and barley was 488.24 × 104 USD and 828.29 × 104 USD, respectively. Besides, the total ecosystem services value of cropland increased by 1564.98 × 104 USD. Further analysis found that the change in the crop planting structure caused an increase in the ecosystem services value of cropland of 359.44 × 104 USD, with a contribution rate of 22.97% to the total increase. The expansion of corn caused the increase of the ecosystem services value of cropland by 151.65 × 104 USD, with a contribution rate of 9.69% to the total increase. The change in crop planting structure in Minle County increased not only the economic benefits of crop planting, but also the ecosystem services of cropland.

Bioaccumulation and ecotoxicity increase during indirect photochemical transformation of polycyclic musk tonalide: A modeling study

Polycyclic musks (PCMs) have recently caused a worldwide environmental concern due to their bioaccumulation potential and ecotoxicological effects. Herein, the OH-initiated indirect photochemical transformation mechanism, environmental fate and ecotoxicity of PCMs (by taking tonalide as an example) were theoretically studied. Results show that tonalide can be degraded readily through OH-addition and H-abstraction pathways, with total rate constants of 6.03 × 109–15.8 × 109 M−1 s−1. The OH-addition pathways were dominant at low temperature (<∼287 K), whereas H-abstraction was the dominant pathway at high temperature. Further, the bioconcentration factors (BCF) and aquatic toxicities to fish of all transformation products from H-abstraction pathways were smaller than tonalide. In contrast, these values of most intermediates from OH-addition pathways were up to 8 times higher than tonalide. Particularly, the resultant phenolic product PC1 had a BCF of 5590 L/kg wet-wt, which exceeds the cutoff criterion set for the typically persistent organic pollutants as critically bioaccumulative. Notably, PC1 would mainly be produced under anaerobic aquatic conditions at low temperatures. Therefore, particular attention should be paid to the indirect photochemical products and parental PCMs, particularly the intermediates from OH-addition pathway.

Benefits Derived from Rehabilitating a Degraded Semi‐Arid Rangeland in Communal Enclosures, Kenya

AbstractCombating land degradation in the semi‐arid rangeland of sub‐Saharan Africa is essential to ensure the long‐term productivity of these environments. In the Lake Baringo basin in Kenya, communities and individual farmers restored indigenous vegetation inside enclosures in an effort to combat severe land degradation and address their livelihood problems. This study quantified the benefits of rangeland rehabilitation using yearly communal enclosures' utilisation data compiled by Rehabilitation of Arid Environments (RAE) Trust over a 6‐year period (2005–2010). Results showed that communal enclosures provide a source of income through the sale of fattened livestock, harvested grass seeds, hay, honey and charcoal, among other products. Regression analysis showed an increasing total enclosure income with time. The enclosures also provide grasses for thatching, livestock feed and dry season grazing. Indirect products like milk, blood and meat are essential for household nutrition and food security. These benefits reinforce the management through incentive to maintain existing enclosures and establish new ones and therefore the increasing trend in rangeland enclosure. Increased soil and biomass carbon storage could come with other indirect environmental benefits including improvement in soil quality, land productivity for pasture production and food security, and prevention of land degradation, thus leading to economic, environmental and social benefit for the local agropastoralist communities. Copyright © 2015 John Wiley &amp; Sons, Ltd.

Optimizing the tactical planning in the Fast Moving Consumer Goods industry considering shelf-life restrictions

This paper addresses the optimization of the tactical planning for the Fast Moving Consumer Goods industry using an MILP model. To prevent unnecessary waste and missed sales, shelf-life restrictions are introduced using three methods. The direct method tracks the age of products directly. While it provides optimal solutions, it is computationally inefficient. The indirect method forces products to leave inventory before the end of their shelf-life. It obtains solutions within a few percent of optimality. Moreover, compared to the direct method, the computational time was on average reduced by a factor 32. The hybrid method models the shelf-life directly in the first and indirectly in the second storage stage. It obtains near optimal solutions and, on average, reduces the required computational time by a factor 5 compared to the direct method. Cases containing up to 25, 100, and 1000 SKUs were optimized using the direct, hybrid and indirect method respectively.

Sintering Temperature and Deposition Orientation Effects on Mechanical, Physical Properties and Geometric Distortion of Cu–Ni Single and Multi Material Indirect Sintering Products

Normal 0 false false false IN X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Development of multi material mechanical parts is constantly undertaken to increase functional aspects as well as life cycle . One example is the use of b imaterial which is widely used as a temperature contactor. This paper presents mechanical, physical properties and geometric distortion of Cu-Ni indirect sintering products used to develop Cu-Ni bimaterial products. The experiment was executed with the following method: firstly, Cu and/or Ni powders w ere deposited into cas t iron powder as the supporting powder. Secondly, it was heated in a furnace with varying temperature s of 870 &deg; C , 900 &deg; C and 930 &deg; C with a holding time of four hours. Lastly, d eposition orientation was varied to observe the effect on the occurence of shrinkage. To initiate the multi material s sintering process, single material sintering was performed to observe the ph y sical an d mechanical properties. Based on previous work , multi material sintering of Cu and Ni powders was conducted. The experiment results show that the geometric distortion of the sintering products was influenced by deposition orientation. The Cu and Ni products shrinkage were 49% and 35.33% , respectively . Although the melting temperatur e of Cu and Ni is close, the binding mechanism of the sintered product did not occur . The significant difference of shrinkage levels was the main factor f or the binding m e chanism failure between Cu and Ni materials Normal 0 false false false IN X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Keywords : Cu, indirect sintering, multi materials, Ni

Comparison of Temperature Time Characteristics of Two Indirect Moxibustion Products

The aim of this experiment was to investigate the thermal properties of a new indirect ceramic moxibustion (ICM) in comparison with conventional indirect stick moxibustion (ISM) and to interpret the clinical implications of the data. A thermocouple was installed underneath each moxibustion unit to record temperature, and 10 units were burned for each moxibustion trial. The procedure began when the unit temperature reached 27 ± 1°C and finished when the temperature had returned to 27°C. The maximum unit temperature, time to reach maximum temperature, and duration of combustion were measured for each moxibustion modality. The maximum temperatures for ISM and ICM were 62.5 ± 2.59°C and 50.2 ± 2.53°C, respectively. The times to reach maximum temperature for ISM and ICM were 5.6 and 16.8 minutes, respectively. The two modalities exhibit different thermal properties as ISM showed a higher maximum temperature (p < 0.0001), which can immediately cause third-degree burns, and a steeper slope of temperature change. ICM, however, showed a lower maximum temperature, more slowly reached the maximum temperature (p < 0.0001), and had a longer and stable duration of combustion. This study suggests that ISM and ICM have statistically different thermal properties, and ICM showed safer thermal properties and a more stable heating pattern. Randomized controlled trials involving various moxibustion modalities are required for further clinical evaluation.

Indirect Composite Restoration

The demand for tooth-colored restorations has grown considerably during the last decade. Posterior composite restorations have risen in popularity as a result of the development of improved resin composites, bonding systems and operating techniques. A major limitation of direct composite restoration is the difficulty of controlling the polymerization shrinkage. To overcome this limitation, the indirect fabrication of a composite restoration and cementation with resin cement has been advocated. Unfortunately, the current available resin cements with indirect restorations do not always bond to dentin as strongly as dentin adhesive systems bond with direct resin composite restorations. Several procedural strategies have been proposed for indirect composite restoration. In this regard, the rationale for the indication, characteristics and clinical application is described in this paper. As a result, we will try to suggest the evidence-based guidelines for indirect composite restorations by reviewing each available indirect composite products, technical procedure and pronosis.

Bacterial Community Dynamics during Swine In vitro Fermentation Using Starch as a Substrate with Different Feed Additives for Odor Reduction.

The experiment was conducted by in vitro fermentation and bacterial community analysis to investigate the reduction of odorous compounds in response to the use of feed additives (FA) during carbohydrate overload in growing pigs. Soluble starch at 1% (control) and various FA at 0.1% Ginseng meal (FA1); Persimmon leaf (FA2); Gingko nut (FA3) and Oregano lippia (FA4) were added to fecal slurry and incubated anaerobically for 12 and 24 h. In vitro parameters and microbial diversity of the dominant bacteria following fermentation were analyzed using Denaturing Gradient Gel Electrophoresis (DGGE), band cloning and sequencing of the V3 region. Results showed that total gas production increased with the advancement of incubation (p<0.05). pH values of FAs and control groups were decreased except the FA4 group which increased somewhat from 12 to 24 h (p<0.05). Ammonia nitrogen (NH3-N) and H2S gas concentrations were comparatively lower in both stages in FA4 treatment than in the other groups (p<0.05). Hence, NH3-N concentrations in liquid phases were increased (p<0.05) from 12 to 24 h, but the trend was lowest in FA4 than in the other groups at both stages. The total VFA production was comparatively lower and butyrate levels were moderate in FA4 group than in the the other groups during both stages (p<0.05). Indirect odor-reducing compounds such as NO2, NO3 and SO4 concentrations were higher in the FA4 and FA3 than in the other groups at 24 h (p<0.05). After fermentation, ten dominant bands appeared, six of which appeared in all samples and four in only the FA4 treated group. The total number of DGGE bands and diversity was higher in the FA4-group compared to other groups. Additionally, similarity indices were lowest (71%) in the FA4, which represented a different bacterial community compared with the other groups. These findings indicate that NH3-N, H2S and VFA production was minimal, and pH was also better in the FA4 group than in the other groups. Furthermore, the conversion of odor-reducing indirect compounds or their intermediates was higher in the FA4 group in compared to the other groups. FA4 group generated less odorous products and more indirect products by in vitro fermentation at 24 h, and their microbial pattern appeared to differ from that of the other groups. These findings suggest that this particular FA could change the microbial population, which may have a beneficial effect on odor reduction. It is recommended that the oregano lippia may be supplied to growing pigs as FA along with excess carbohydrate sources to reduce the production of odorous compounds.

Editorial: The Nonsense of Biofuels

Fossil fuels, like mineral oil, coal, and natural gas, are derived from the biomass of ancient times. As such, they are indirect products of photosynthesis. It is therefore appropriate to ask whether we can use currently available biomass and convert it into biofuels like biodiesel and biogas. Biohydrogen might be another option. Often one can read that biofuels are CO2-neutral and therefore a weapon against global warming. Their production is also supposed to reduce the amount of petrol and natural gas to be imported into many countries, thus making them less dependent on energy import. In the following, I shall discuss the efficiencies of the processes required to produce biofuels, compare them with alternatives, draw the obvious conclusions, and present some visions.

Dealing with the Unknown: Metabolomics and Metabolite Atlases

Metabolomics is the comprehensive profiling of the small molecule composition of a biological sample. Since metabolites are often the indirect products of gene expression, this approach is being used to provide new insights into a variety of biological systems (clinical, bioenergy, etc.). A grand challenge for metabolomics is the complexity of the data, which often include many experimental artifacts. This is compounded by the tremendous chemical diversity of metabolites. Identification of each uncharacterized metabolite is in many ways its own puzzle (compared with proteomics, which is based on predictable fragmentation patterns of polypeptides). Therefore, effective data reduction/prioritization strategies are critical for this rapidly developing field. Here we review liquid chromatography electrospray ionization mass spectrometry (LC/MS)-based metabolomics, methods for feature finding/prioritization, approaches for identifying unknown metabolites, and construction of method specific 'Metabolite Atlases'.

Energetics and Reaction Mechanisms for the Competitive Losses of H2, CH4 and C2H4 from Protonated Methylbenzenes—Implications to the Methanol-to-Hydrocarbons (MTH) Process

We report the unimolecular decomposition following collisional activation of protonated mono-, di- and trimethylbenzenes as a function of collision energy. The resulting energy-resolved mass spectra are then used for the quality control of high-level quantum chemical models of the respective potential energy surfaces. Distinction is made between direct dissociation products (CH(4) or H(2)) and indirect products (alkenes), since formation of the latter requires extensive rearrangement of the molecular skeleton. Very good consistency was found between model and experiment. The models thereby provide a solid foundation for discussing the reaction mechanisms of the industrial methanol-to-hydrocarbon process. The losses of CH(4), C(2)H(4) and C(3)H(6) from mesitylenium ions have been studied by (13)C and (2)H labelling and the alkene losses were found to occur via irreversible isomerisation pathways.

The economic benefits of forage improvement in the United States

The United States is a large country with a diversity of forage ecosystems and forage species to fill the varied management options within each ecosystem. For example, the American Seed Trade estimates seed of 5,500 varieties representing 1,500 grass and 4,000 legume species are produced annually. The economic benefits of forage improvement are both direct (seed and hay sales) and indirect (saleable animal products, nitrogen fixation and conservation uses). The benefits of improving forages through breeding are likewise important due to the current use of improved varieties to underpin these systems and their direct and indirect products. Because of the diversity of species and management systems, only a few case studies were examined in this paper to estimate these benefits. These were the alfalfa (Medicago sativa L.) industry (economic value of US$8.1 billion per year), the forage and livestock systems of the southeastern USA (economic value estimated overall at US$11.4 billion per year), and switchgrass (Panicum virgatum L.) and its potential use as bio-energy feedstock (economic value of needing an additional 28 million acres of production to supply the estimated future feedstock needs). The overall conclusion is that the economic benefits from forage improvement in the USA have been, and continue to be, immense. However, future resources are going to fewer crops, and these crops are the ones that have greater economic value and where biotechnology can be applied. This will favor alfalfa and penalize forage grasses. Even for crops with an identifiable path to market, this concentration of resources in fewer hands requires development of consortia where organizations can leverage their resources with others who possess complementary resources. The Consortium for Alfalfa Improvement is a good example of how this could work.

Gene-balanced duplications, like tetraploidy, provide predictable drive to increase morphological complexity

Controversy surrounds the apparent rising maximums of morphological complexity during eukaryotic evolution, with organisms increasing the number and nestedness of developmental areas as evidenced by morphological elaborations reflecting area boundaries. No "predictable drive" to increase this sort of complexity has been reported. Recent genetic data and theory in the general area of gene dosage effects has engendered a robust "gene balance hypothesis," with a theoretical base that makes specific predictions as to gene content changes following different types of gene duplication. Genomic data from both chordate and angiosperm genomes fit these predictions: Each type of duplication provides a one-way injection of a biased set of genes into the gene pool. Tetraploidies and balanced segments inject bias for those genes whose products are the subunits of the most complex biological machines or cascades, like transcription factors (TFs) and proteasome core proteins. Most duplicate genes are removed after tetraploidy. Genic balance is maintained by not removing those genes that are dose-sensitive, which tends to leave duplicate "functional modules" as the indirect products (spandrels) of purifying selection. Functional modules are the likely precursors of coadapted gene complexes, a unit of natural selection. The result is a predictable drive mechanism where "drive" is used rigorously, as in "meiotic drive." Rising morphological gain is expected given a supply of duplicate functional modules. All flowering plants have survived at least three large-scale duplications/diploidizations over the last 300 million years (Myr). An equivalent period of tetraploidy and body plan evolution may have ended for animals 500 million years ago (Mya). We argue that "balanced gene drive" is a sufficient explanation for the trend that the maximums of morphological complexity have gone up, and not down, in both plant and animal eukaryotic lineages.

From genomes to systems: the path with yeast.

Metabolic Control Analysis (MCA) is a conceptual and mathematical formalism that models the relative contributions of individual effectors in a pathway to both the flux through the pathway and the concentrations of individual intermediates within it. To exploit MCA in an initial Systems Biology analysis of the eukaryotic cell, two categories of experiments are required. In category 1 experiments, flux is changed and the impact on the levels of the direct and indirect products of gene action is measured. We have measured the impact of changing the flux on the transcriptome, proteome and metabolome of Saccharomyces cerevisiae. In this whole-cell analysis, flux equates to growth rate. In category 2 experiments, the levels of individual gene products are altered, and the impact on the flux is measured. We have used competition analyses between the complete set of heterozygous yeast deletion mutants to reveal genes encoding proteins with high flux control coefficients. These genes may be exploited, in a top-down analysis, to build a coarse-grained model of the eukaryotic cell, as exemplified by yeast. More detailed modelling requires that 'natural' biological systems be identified. The combination of flux balance analysis with both genetics and metabolomics in the definition of metabolic systems is discussed.

Commercial Program and Product Review: Indirect Calorimetry Products for the Office

Commercial Program and Product Review: Indirect Calorimetry Products for the Office

Increased phospholipase activity in Helicobacter pylori strains isolated from patients with gastric carcinoma

Purpose. Phospholipase activity, one of Helicobacter pylori pathogenicity factors, has not been investigated enough, so far, although it may induce a remarkable damage to the gastric mucosa. In the present work, we have compared the whole phospholipase activity of H. pylori strains isolated from patients with gastric carcinoma with that of strains isolated from dyspeptic patients without gastric carcinoma. Methods. We measured the phospholipase activity of one distinct H. pylori colony isolated from each of 10 patients with gastric carcinoma and 10 controls, dyspeptic patients without endoscopic and histological signs of gastric carcinoma. We also determined the phospholipase activity of 20 additional strains isolated from different areas of neoplastic and non-neoplastic tissue of two patients with gastric carcinoma, the cagA and vacA positive G27 and 328 wild strains and their respective vacA and cagA negative isogenic mutants. The whole phospholipase activity of strains was determined by measuring the release of 14C-labeled palmitic acid from the radioactive l-3-phosphatidylcholine, 1,2-di[1- 14C]palmiloyl substrate; results were expressed in pmol of palmitic acid per mg of protein. Results. H. pylori strains isolated from patients with gastric carcinoma had levels of phospholipase activity significantly higher than those of strains isolated from controls (99.37 [S.D. 40.45] versus 34.46 [S.D. 16.46], P < 0.001). In patients with gastric carcinoma, the mean phospholipase activity of strains isolated from neoplastic tissue was similar to that of strains isolated from non-neoplastic tissues (123.02 [S.D. 44.36] and 115.77 [S.D. 81.48], respectively. Interruption of cagA gene caused a ca. 20% reduction of phospholipase activity (36.38 versus 45.22 of the wild strain); that of vacA caused no reduction of phospholipase activity (26.53 and 25.37 of the wild strain). Conclusions. The infection by H. pylori strains that produce high levels of phospholipase may increase the risk of developing gastric carcinoma. We hypothesise that indirect products of phospholipase activity, such as prostaglandins, leukotrienes and lysophospholipids, may mediate carcinogenesis.

Agents of change in the retail warehouse market

This paper examines the consolidation of occupation and ownership within the retail warehouse park property sector and the polarisation of existing schemes towards fashion, bulky goods destination and convenience parks — a process accelerated by continuing occupier and investor demand and a lack of supply, restricted by tighter town planning controls. Two case studies — Deepdale Park, Preston and St Andrews Quay, Hull — are used to illustrate park evolution and demonstrate the sector's attractiveness to investors and developers, brought together through innovative joint ventures and limited partnerships to facilitate the redevelopment process and create new indirect investment products.

Feasibility and synthesis of hybrid reactive distillation systems

AbstractA systematic method to synthesize hybrid reactive distillation configurations described here uses three building blocks. These building blocks are a cocurrent rectifying cascade, a cocurrent stripping cascade, and a countercurrent cascade. A feasibility diagram and a product purity diagram provide a global view of the “direct” and “indirect” sharp split products that can be obtained as a function of the reaction rate from single–feed and double–feed hybrid columns, respectively. These diagrams are used as a basis for quickly and systematically generating feasible column configurations (if any) that produce the desired product. Three esterification examples are used to illustrate the method. In spite of the fact that the examples form a homologous series, the feasible designs are quite different. The results compare well with column simulations.

Reasons, Robots and the Extended Mind

A suitable project for the new Millenium is to radically reconfigure our image of human rationality. Such a project is already underway, within the Cognitive Sciences, under the umbrellas of work in Situated Cognition, Distributed and De‐centralized Cognition, Real‐world Robotics and Artificial Life. Such approaches, however, are often criticized for giving certain aspects of rationality too wide a berth. They focus their attention on such superficially poor cousins as ‘adaptive behaviour’, ‘ecologically sound perception‐action routines’, ‘fast and frugal heuristics’ and ‘fast, fluent real‐time real‐world action control’. Is this robbery or revelation? Has ‘embodied, embedded’ cognitive science simply lost sight of the very phenomena it was meant to explain? Or are we finally seeing rationality aright, as fully continuous with various forms of simpler, ecologically situated, adaptive response? I distinguish two ways of developing the ‘embodied, embedded’ approach. The first, which does indeed threaten to lose sight of the key targets, is fully committed to a doctrine of biological cognitive incrementalism according to which full‐scale human rationality is reached, rather directly, by some series of tweaks to basic biological modes of adaptive response. The second depicts human capacities for advanced reason as at best the indirect products of such a process. Such capacities, it is argued, depend heavily upon the effects of a special kind of hybridization in which human brains enter into an increasingly potent cascade of genuinely symbiotic relationships with knowledge‐rich artifacts and technologies. This latter approach, I finally suggest, does better justice to our peculiar profile, which combines deep biological continuity with an equally deep cognitive discontinuity.