The upside-down jellyfish
Cassiopea
has become a model organism for the study of symbiosis between dinoflagellates and cnidarian hosts. Most previous studies have indicated that the presence of ...symbiotic zooxanthellae is a key requirement for strobilation in
Cassiopea
. Indole compounds have been shown to induce strobilation in many scyphozoans, including symbiotic
Cassiopea xamachana
. To determine if indoles could induce aposymbiotic
Cassiopea
polyp strobilation, we acquired algal-free
Cassiopea andromeda
polyps and used three indoles (indomethacin, 2-methyl indole, and 5-methoxy-2-methyl indole) to induce metamorphosis by applying single doses within a range of 0.005–100 μM. Analysis showed that indoles successfully induced aposymbiotic polyp strobilation and that the induction effects were compound- and dose-dependent. 5-Methoxy-2-methyl indole and 2-methyl indole were significantly more effective than indomethacin (
P
< 0.001). Data showed that it took 3 to 9 days for 5-methoxy-2-methyl indole or 2-methyl indole to induce strobilation and that 25 μM of 2-methyl indole was the most effective inducer of strobilation in algae-free
C. andromeda
polyps. Indole-induced strobilation was associated with several developmental abnormalities, including failed or retarded regeneration of residual polyps after strobilation, a reduction in the size of ephyrae, and abnormal morphology of the ephyrae.
The emergence of Life Cycle Assessment (LCA) on the global stage as a design and policy tool increases the importance of assessing and managing uncertainty. This article develops and implements ...uncertainty methods for hybrid LCA. Hybrid LCA combines a bottom–up construction of the supply-chain based on facility-level data on material/energy use with a top–down economic input–output (EIO) model to account for processes for which direct data were unavailable. For the bottom–up part of the LCA, we account for variability in process and usage pattern data by developing parameter ranges. For the EIO side we develop a method to assess price uncertainty. These methods are explored through a case study examining energy use and carbon dioxide emissions of manufacturing and use of a laptop computer, a 2001 Dell Inspiron 2500. Results show that manufacturing the computer requires 3010–4340 MJ of primary energy, 52–67% less than the energy to make a desktop computer, and emits 227–270 kg CO
2. The manufacturing phase represents 62–70% of total primary energy of manufacturing and operation. This indicates, as for desktop computers, that mitigating manufacturing energy use, for example through extending lifespan, can be an important strategy to manage the life cycle energy of laptop computers. Results also indicate that truncation error from excluded processes in the bottom–up process model is significant, perhaps particularly so due to complex supply chains of information technology products.
Recurrent events are very common in many different fields, including biological, medical, engineering and finance. Existing research have developed methodologies to model constant covariate effects ...and time-dependent covariate effects. However, in reality, for instance medical cases, covariate effects can be depending on other covariates as well. Therefore, in this dissertation, we investigate a semiparametric model for recurrent events, which incorporates both time-varying covariate effects and covariate-varying effect. In our model, we use fixed parameters to model constant covariate effects, while we assume both time-dependent effects and covariate-varying effects to be unknown functions. An estimation procedure is proposed to estimate the unknow parameters and functions. Local linear smoothing method is adopted in our estimation procedure. Detailed computation is carried out by using Newton-Raphson iterative method. The asymptotic properties including asymptotic normality and consistency are established for the proposed estimators. In order to assess the finite-sample performance of the proposed estimators and estimation procedure, simulation studies are conducted for different cases. The simulation results show that the proposed estimators perform very well with small bias and an empirical coverage probability close to its nominal level 95%. In addition, the proposed model and methodologies are applied on the dataset from the Hemodialysis Study (HEMO). The data applications are aiming at examining the treatment effects of two different design in the study and exploring factors that are associated with hemodialysis patients' mortality and hospitalization rate. The results show that both treatments are not significant at neither reducing mortality risk nor hospitalization rate for hemodialysis patients. Some factors, including sex, age, baseline serum albumin level, ICED score and diabetes, are found to be significantly associated with the mortality and hospitalization rate for hemodialysis patients.
Summary
Technological progress and adoption are fundamentally interconnected with environmental challenges faced by society. At the product level, researchers often explore the interplay between ...technological change and the environment by tracking trends in impacts per unit functionality—for example, gasoline consumed per distance traveled by a vehicle. In this article, we explore an alternative measure: “typical product.” A typical product measure accounts for changes in consumers’ demand and use of products as product quality improves—for example, gasoline consumed for a typical driving pattern for a vehicle. We compare and contrast functionality and typical product measures through a case study of electricity use to fabricate Intel desktop microprocessors from 1995 to 2006. The functionality normalization is measured in terms of electricity use per transistor produced. Results show rapid and sustained exponential decrease. The “typical product” measures electricity use per typical desktop microprocessor of a given year (e.g., a Pentium II in 1998, a Pentium IV in 2002). Results show that, despite fluctuations, energy use per typical microprocessor is roughly constant over the 12‐year period. The explanation of this result is that although technological progress dramatically reduces the energy needed per transistor, it also induces demand for more powerful chips, which contain many more transistors. The typical product measure has applications in defining functional units in life cycle assessment, characterizing rebound effects, and measuring energy efficiency trends.
Technological progress and adoption are fundamentally interconnected with environmental challenges faced by society. At the product level, researchers often explore the interplay between ...technological change and the environment by tracking trends in impacts per unit functionality - for example, gasoline consumed per distance traveled by a vehicle. In this article, we explore an alternative measure: typical product. A typical product measure accounts for changes in consumers' demand and use of products as product quality improves - for example, gasoline consumed for a typical driving pattern for a vehicle. We compare and contrast functionality and typical product measures through a case study of electricity use to fabricate Intel desktop microprocessors from 1995 to 2006. The functionality normalization is measured in terms of electricity use per transistor produced. Results show rapid and sustained exponential decrease. The typical product measures electricity use per typical desktop microprocessor of a given year (e.g., a Pentium II in 1998, a Pentium IV in 2002). Results show that, despite fluctuations, energy use per typical microprocessor is roughly constant over the 12-year period. The explanation of this result is that although technological progress dramatically reduces the energy needed per transistor, it also induces demand for more powerful chips, which contain many more transistors. The typical product measure has applications in defining functional units in life cycle assessment, characterizing rebound effects, and measuring energy efficiency trends.
We analyze trends in electricity use to fabricate typical Intel CPUs from 1995 to 2005. Two sets of energy consumption data for semiconductor fabrication were collected: from the annual survey of ...manufacturers (ASM) of the U.S. Census and annual reports from the Taiwanese semiconductor manufacturer UMC. Analysis indicates that the difference between the two data sources is small despite being very different aggregations of device production and geographical location. We combine this information with technical specifications of Intel CPUs to measure trends in energy use according to two different functional units. The first measure, electricity use per transistor, displays rapid and sustained decreases, with 98% reduction from 1995 to 2005. This behavior is reminiscent of Moorepsilas Law and reflects rapid technological progress in the industry. The second measure, electricity use per typical CPU for a given year (e.g. Pentium II for 1998), displays fluctuations but surprisingly is roughly constant over the 10-year period. The explanation for this constant behavior is that while technological progress reduces the energy use per transistor, it also enables demand for more powerful chips which contain many more transistors. The two effects, according to this analysis, roughly balance. We do not interpret this result as a lack of effort of the industry to pursue energy efficiency, rather as a fundamental dynamic for sectors in which processes and products are co-evolving. This result calls for a rethinking of how we conceptualize and benchmark efficiency improvements in rapidly evolving sectors.
Abstract Accurate and flexible control of droplets is essential in many industrial applications, such as water harvesting, chemical assays, and biological detection. Magnetic force‐based methods have ...been broadly exploited to fulfill the goals due to the advantage of non‐contact, easy control, and long‐range navigation. Nevertheless, it still suffers from some challenges, such as sample fouling, and the paradox between the droplet efficient motion and the large volume. Here a ferrofluid‐based liquid spring to achieve contamination‐free and fast droplet transportation on non‐wetting solid surfaces is proposed. The liquid spring is based on the actuation of a ferrofluid droplet in an external uniform magnetic field. The actuation enables the liquid spring to propel tiny objects, including the non‐magnetic miscible droplets and water‐repellent solid particles, with adjustable motion velocity. Furthermore, the magnetic force, applied on the ferrofluid via an additional permanent magnet, makes it possible to navigate the liquid spring in a programmable way. With the aid of the liquid spring, the single or multiple droplets/solid particles advancing, on‐demand droplets coalescence, and out‐of‐plane droplet motion are achievable.
•We established a finite element model of HTHP diamond synthesis cavity stacked with sheet alloy catalyst and graphite.•The distribution of temperature fields and heat fluxes inside the cavity were ...analyzed In different power distribution.•The growth wasteland was explored through simulation analysis.
In this study, the thermodynamics and heat conduction of the diamond synthesis cavity of flake catalyst were theoretically analyzed and mathematically deduced to discuss the temperature field and the distribution of pyrophyllite synthesis cavity in flake catalyst-graphite's high-pressure and high-temperature (HTHP) synthesis. The thermal flux and temperature distribution of the pyrophyllite synthesis cavity and the temperature field of the flake catalyst-graphite synthesis rod were simulated and calculated. The calculations revealed that the synthetic rod's temperature rapidly increased in the initial 100 s of heating; When the heating time increased from 100 s to 150 s, the heating rate of the synthetic rod started to slow down. The temperature of the synthetic rod was stable after 170 s of heating, and the whole synthetic rod system reached the thermal equilibrium state; the temperature field of the synthetic rod was also stable. In a steady state, the maximum radial temperature gradient of the sheet catalyst graphite synthetic rod is 0.54 °C/mm, and the axial temperature gradient is about 2.93 °C/mm. The axial temperature gradient inside the synthetic rod was significantly higher than the radial temperature gradient. Further calculations showed that the heat flux of the pyrophyllite synthetic block on the inner wall of the pyrophyllite synthetic cavity was 2734 W in the heating direction, which was greater than that in the non-heating direction around 1312 W. The heat flux of the conductive steel cap in the heating direction was 2436 W, accounting for 60.1% of the total heat flux; This is the main reason for the large axial temperature gradient of the lamellar catalyst-graphite synthesis rod in the pyrophyllite cavity. A comparison of the temperature field of the cavity under different powers revealed that the temperature inside the cavity produces excessive diamond growth wasteland when the power is too high or too low.
Bone regeneration and repair has become one of the major clinical challenges worldwide and it involves multiple processes including inflammation, angiogenesis and osteogenesis. In this study, we ...synthesized strontium Laminarin polysaccharide (LP-Sr), a novel polysaccharide-metal complex that should have therapeutic effects on modulating osteogenesis and angiogenesis. The structure and composition of the as-fabricated LP-Sr were analyzed by EDS, XRD, FITR, 1H NMR, HPLC, etc. The results indicate that we successfully synthesized this novel polysaccharide complex. Moreover, we evaluated the biomedical potential of this complex in promoting osteogenesis and angiogenesis by cell proliferation assay, ALP staining, immunofluorescent staining of CD31 and reverse transcription polymerase chain reaction (RT-PCR). The biological experiment results show that LP-Sr can effectively promote proliferation and increase the expression of VEGF and EGFL6 in HUVECs and significantly up-regulate the expression of Col1α1 and OCN in MC3T3-E1. Besides, it is suggested that LP-Sr has positive effects on the suppression of pro-inflammatory factor IL6 in both HUVECs and MC3T3-E1. Moreover, the osteogenic and angiogenic markers, i.e. alkaline phosphatase (ALP) and CD31, exhibited high expression in LP-Sr group. Hence, we believe that LP-Sr should be a promising and novel polysaccharide complex in modulating osteogenesis-angiogenesis for bone regeneration.
Directional liquid transport has been widely observed in various species including cacti, spiders, lizards, the pitcher plant Nepenthes alata , and Araucaria leaves. However, in all these examples ...the liquid transport for a specific liquid is completely restricted in a fixed direction. We demonstrate that Crassula muscosa shoot surfaces have the ability to transport a specific liquid unidirectionally in either direction. This is accomplished through the presence of asymmetric reentrant leaves with varying reentrant angles, which yields the variation in liquid meniscus heterogeneity. These findings enable engineered biomimetic structures capable of selective directional liquid transport, with functions such as intelligent flow direction switching, liquid distribution, and mixing.
Editor’s summary Both engineered and natural structures can exhibit directional liquid transport that is driven by the specific patterning of the surface. Yang et al . drew inspiration from the Crassula muscosa plant, in which the direction of fluid flow is determined by the shape and orientation of the structured fins, which can vary from stem to stem, and by the surface tension of the fluid. The authors constructed biomimetic counterparts that can include magnetic particles, which allows for changes in the flow directions simply through small changes in the angle and geometry of the fins. —Marc S. Lavine
