Computational framework for simulating fluorescence microscope images with cell populations

Fluorescence microscopy combined with digital imaging constructs a basic platform for numerous biomedical studies in the field of cellular imaging. As the studies relying on analysis of digital images have become popular, the validation of image processing methods used in automated image cytometry has become an important topic. Especially, the need for efficient validation has arisen from emerging high-throughput microscopy systems where manual validation is impractical. We present a simulation platform for generating synthetic images of fluorescence-stained cell populations with realistic properties. Moreover, we show that the synthetic images enable the validation of analysis methods for automated image cytometry and comparison of their performance. Finally, we suggest additional usage scenarios for the simulator. The presented simulation framework, with several user-controllable parameters, forms a versatile tool for many kinds of validation tasks, and is freely available at http://www.cs.tut.fi/sgn/csb/simcep.     

Role of forest sector and bioenergy in limiting the carbon emissions of Finland

The greenhouse impacts of the Finnish forest sector, including the forest biomass, forest industry, forest products in use, foreign trade and waste management are discussed. The main carbon storages and flows are estimated and the greenhouse gas balance both totally and on national level are presented. The history of the greenhouse impact is also estimated and two future scenarios of the forest sector are compared. The present use and potential for additional use of bioenergy is also reviewed, and the impact of expanded bioenergy use on the national CO₂ emissions is illustrated with scenario examples.     

Comparison of dye solar cell counter electrodes based on different carbon nanostructures

Three characteristically different carbon nanomaterials were compared and analyzed as platinum-free counter electrodes for dye solar cells: 1) single-walled carbon nanotube (SWCNT) random network films on glass, 2) aligned multi-walled carbon nanotube (MWCNT) forest films on Inconel steel and quartz, and 3) pressed carbon nanoparticle composite films on indium tin oxide-polyethylene terephtalate plastic. Results from electrochemical impedance spectroscopy and electron microscopy were discussed in terms of the catalytic activity, conductivity, thickness, transparency and flexibility of the electrode films. The SWCNT films showed reasonable catalytic performance at similar series resistance compared to platinized fluorine doped tin oxide-coated glass. The MWCNTs had similar catalytic activity, but the electrochemical performance of the films was limited by their high porosity. Carbon nanoparticle films had the lowest charge transfer resistance resulting from a combination of high catalytic activity and dense packing of the material.     

Flavor challenges in extruded plant-based meat alternatives: A review

Demand for plant-based meat alternatives has increased in recent years due to concerns about health, ethics, the environment, and animal welfare. Nevertheless, the market share of plant-based meat alternatives must increase significantly if they are to support sustainable food production and consumption. Flavor is an important limiting factor of the acceptability and marketability of plant-based meat alternatives. Undesirable chemosensory perceptions, such as a beany flavor, bitter taste, and astringency, are often associated with plant proteins and products that use them. This study reviewed 276 articles to answer the following five research questions: (1) What are the volatile and nonvolatile compounds responsible for off-flavors? (2) What are the mechanisms by which these flavor compounds are generated? (3) What is the influence of thermal extrusion cooking (the primary structuring technique to transform plant proteins into fibrous products that resemble meat in texture) on the flavor characteristics of plant proteins? (4) What techniques are used in measuring the flavor properties of plant-based proteins and products? (5) What strategies can be used to reduce off-flavors and improve the sensory appeal of plant-based meat alternatives? This article comprehensively discusses, for the first time, the flavor issues of plant-based meat alternatives and the technologies available to improve flavor and, ultimately, acceptability.     

用碱回收炉提高发电量

20世纪碱回收炉的主要任务是回收有价值的割浆蒸煮药液，发电并不重要。现如今．用娥回收炉采增加发电量的重要性不断提高。这些变化的主要原因是电的价格。本文将介绍增加电产量的传统方法、新的思想和见解，特别是采用冷凝汽轮机其主要目的在于展示这些方法的效果．以便于其结果的可比性。本研究的基本事例为1台传统的碱回收炉，生产能力为4000t(固形物)／d，同时配备有备压汽轮机和冷凝汽轮机。本文将要介绍的方法为：增加黑液固含量、空气预热、吹灰系统、给水预热、蒸汽参数和电除尘后的热回收。     

Light-scattering efficiency of starch acetate pigments as a function of size and packing density

We study theoretically the light-scattering efficiency of paper coatings made of starch acetate pigments. For the light-scattering code we use a discrete dipole approximation method. The coating layer is assumed to consists of roughly equal-sized spherical pigments packed either at a packing density of 50% (large cylindrical slabs) or at 37% or 57% (large spheres). Because the scanning electron microscope images of starch acetate samples show either a particulate or a porous structure, we model the coatings in two complementary ways. The material can be either inside the constituent spheres (particulate case) or outside of those (cheeselike, porous medium). For the packing of our spheres we use either a simulated annealing or a dropping code. We can estimate, among other things, that the ideal sphere diameter is in the range 0.25-0.4 microm.     

Problem absorption as an organizational learning mechanism in project-based companies: Process thinking perspective

In organizations existing rules and norms are usually used as the basis for solving new problems even when this means stretching those rules. Such absorption of new problems by rules reduces the need to explore and develop new solutions and to encode those solutions into new rules. Furthermore, one way that organizational learning can occur is through problem solving, i.e. learning takes place through identifying and resolving problems that occur in the execution of projects. Thus, finding a viable perspective and approach with which project-based companies can understand how their organizational learning through problem solving activities take place in the course of time is a very important issue. Therefore, the goal of this paper is to explore the potential of process thinking to open up new ways to understand organizational learning – particularly through problem absorption within problem solving – in project-based companies. All in all, with the help of this paper we have sought to offer a brief illustration of how process thinking may help to understand this issue.     

On Learning and Cross-Validation with Decomposed Nyström Approximation of Kernel Matrix

The high computational costs of training kernel methods to solve nonlinear tasks limits their applicability. However, recently several fast training methods have been introduced for solving linear learning tasks. These can be used to solve nonlinear tasks by mapping the input data nonlinearly to a low-dimensional feature space. In this work, we consider the mapping induced by decomposing the Nyström approximation of the kernel matrix. We collect together prior results and derive new ones to show how to efficiently train, make predictions with and do cross-validation for reduced set approximations of learning algorithms, given an efficient linear solver. Specifically, we present an efficient method for removing basis vectors from the mapping, which we show to be important when performing cross-validation.     

Friction reduction by texturing of DLC coatings sliding against steel under oil lubrication

It has been demonstrated that tetrahedral amorphous carbon (ta-C) films provide excellent wear and friction properties in dry sliding. Recently the applications of ta-C coatings in lubricated conditions have become more important. The use of carbon coatings aims at reducing the wear and coefficient of friction under minimum lubrication and without hazardous lubricant additives. For optimum tribological performance, a modification of the ta-C coated surfaces is required. The present paper describes an innovative method of coated surface texturing, by which nanometer and micrometer size pores are processed by various methods. Particle masking was used for processing micrometer size pores and for controlling the coating growth conditions in order to produce nanometer size pores in the ta-C surface. The masking by particles yielded a pore geometry which varied from complex shaped channels to small individual pores. The texturing was performed by distributing metallic powder particles on the surface or by direct chemical deposition of metal particles on the substrate in prior to pulsed vacuum arc deposition. The tribological characterization was carried out by applying reciprocating friction tests with controlled lubricant replenishment, in order to simulate metal forming processes. The friction reducing effect, which was observed in the tribological tests, indicated a microlubrication effect of the textured coating surfaces.