Innovative method of Transthoracic Lung Cancer Biopsy of Parietal Lung Tumors under US Guidance after CT Pre-biopsy Planning as an Alternative to CT- Guided Biopsy

The authors compared their earlier results of the tumor biopsies performed under computer tomography （CT） guidance against the results of their recently modified-combined method of visualization and measurement of lung tumor parameters by CT imaging followed by US guided biopsy. In 238 （6.36%） of 3,745 patients in CT examination, the lung tumor was located peripherally, and obtaining histopathological confirmation was crucial to start the proper treatment. The patients were divided into two groups, the division was based on the biopsy method. Within the first group in I 18 patients, parietal lung tumor was confirmed and CT guided biopsy was performed. Within the second group, parietal lung tumor was confirmed in 120 patients and combined method of CT pre- biopsy planning and US guided biopsy were used. Pre-biopsy planning was performed using CT, measurements such as depth and distance of the tumor were made, obtained data were then saved on CT image and patient＇s skin was marked. Then obtained results were analyzed using test for two proportions. The analysis of the results confirmed the higher efficacy of the combined method taking into account the number of complications （p 〈 0.01） and diagnostic histopathological results （P 〈 0.001）. Suggested innovative method, involving both CT pre-biopsy planning and US guided biopsy, allows to analyze simultaneously static CT and dynamic US images and it is considered to be an easy and effective method comparing to relying on static in nature CT images only. Our method is related to a lower complication risk rate.     

Polymer track membranes as a trap support for reagent in fiber optic sensors

The article presents a new idea of the application of polymer track membranes (PTM) for immobilization of a reagent in fiber optic chemical sensors. PTM was made of a poly(ethylene terephthalate) foil (10 μm in thickness, pores of 0.2 μm in diameter). The usefulness of membranes additionally covered by poly(vinyl chloride) was tested in a fiber optic redox titrator. The titrator utilized N,N′-diphenylbenzidine as a reagent which changes its absorbance in dependence on the redox potential. The measuring system is based on a lightemitting diode and a silicon photodiode connected to a bifurcated fiber optic bundle. The gain is in price and availability of the membrane. © 1996 John Wiley & Sons, Inc.     

Existence of positive periodic solutions of certain ordinary differential equations

The method of ascertaining the existence and uniqueness of positive periodic solutions of certain ordinary differential equations has been presented. A nuclear reactor with negative temperature reactivity coefficient and periodic control reactivity has been considered as an illustrative example.     

Investment Climate Constraints as Determinants of Political Tie Intensity in Emerging Countries: Evidence from Foreign Firms in Ghana

Foreign firms in emerging countries face various institutionally-driven challenges. Nonmarket strategy scholars argue that these challenges incite corporate political activity. Consequently, researchers have explored the influence of institutional factors on the choice and extent of political strategies. However, not much is known about how investment climate constraints affect the political ties of foreign firms in contexts other than US, Europe and Asia. Drawing on institutional theory, we propose that firms’ exposure to administrative and control constraints as well as the presence of public affairs (PA) functions will lead to political tie intensification. We test our propositions using data from foreign firms operating in Ghana, and find that whereas control constraints strengthen political ties, administrative constraints weaken these ties. The findings also suggest that PA functions and political ties can be substitutes, not complements, depending on the institutional contingencies. Altogether, our study enhances knowledge and understanding of how institutional environments and organizational structures affect the political behaviour of foreign firms in emerging countries.     

Dynamic thermal modelling of a power integrated circuit with the application of structure functions

This paper presents dynamic thermal analyses of a power integrated circuit with a cooling assembly. The investigations are based on the examination of the cumulative and differential structure functions obtained from the circuit cooling curves recorded during transient circuit temperature measurements. The experiments carried out and the comprehensive study of the computed structure functions rendered possible determination of the interface contact resistance and the heat transfer coefficient values necessary for numerical thermal simulations illustrating the influence of these thermal model parameters on circuit temperature.     

Peer-to-peer data structures for cooperative traffic information systems

Cooperative traffic information systems support the driver of a car in selecting a route, based on traffic information collected by other cars. We propose to use a peer-to-peer network based on Internet access via cellular networks to distribute traffic information between the participants of such a system. This approach avoids the well-known limitations of VANET-based communication. Since the data maintained in a cooperative traffic information system has a very specific structure, it is particularly profitable—in terms of bandwidth consumption and latency—to tailor the system to this specific application domain instead of re-using generic peer-to-peer approaches. This realization led us to the development of GraphTIS—a peer-to-peer network specifically designed to manage traffic information. In this paper, we derive, step-by-step, the core mechanisms of GraphTIS, starting with a standard peer-to-peer system, outlining a first solution—named PeerTIS—which is based on a modification of this standard DHT, and then presenting GraphTIS, a novel peer-to-peer system that has been specifically designed to support traffic information systems.     

Si-rich Al2O3 films grown by RF magnetron sputtering: structural and photoluminescence properties versus annealing treatment

Silicon-rich Al₂O₃ films (Si_x(Al₂O₃)_1−x) were co-sputtered from two separate silicon and alumina targets onto a long silicon oxide substrate. The effects of different annealing treatments on the structure and light emission of the films versus x were investigated by means of spectroscopic ellipsometry, X-ray diffraction, micro-Raman scattering, and micro-photoluminescence (PL) methods. The formation of amorphous Si clusters upon the deposition process was found for the films with x ≥ 0.38. The annealing treatment of the films at 1,050°C to 1,150°C results in formation of Si nanocrystallites (Si-ncs). It was observed that their size depends on the type of this treatment. The conventional annealing at 1,150°C for 30 min of the samples with x = 0.5 to 0.68 leads to the formation of Si-ncs with the mean size of about 14 nm, whereas rapid thermal annealing of similar samples at 1,050°C for 1 min showed the presence of Si-ncs with sizes of about 5 nm. Two main broad PL bands were observed in the 500- to 900-nm spectral range with peak positions at 575 to 600 nm and 700 to 750 nm accompanied by near-infrared tail. The low-temperature measurement revealed that the intensity of the main PL band did not change with cooling contrary to the behavior expected for quantum confined Si-ncs. Based on the analysis of PL spectrum, it is supposed that the near-infrared PL component originates from the exciton recombination in the Si-ncs. However, the most intense emission in the visible spectral range is due to either defects in matrix or electron states at the Si-nc/matrix interface.     

Real time repeated video sequence identification

In this paper, we present a real time system for detecting repeated video clips from a live video source such as news broadcasts. Our system utilizes customized temporal video segmentation techniques to automatically partition the digital video signal into semantically sensible shots and scenes. As each frame of the video source is processed, we extract auxiliary information to facilitate repeated sequence detection. When the video transition marking the end of the shot/scene is detected, we are able to rapidly locate all previous occurrences of the video clip. Our objective is to use repeated sequence information in our multimedia content analysis application to deduce semantic relationships among shots/scenes in the input video. Our real time video processing techniques are independent of source and domain and can be applied to other applications such as commercial detection and improved video compression.     

Generation of reduced dynamic thermal models of electronic systems from time constant spectra of transient temperature responses

This paper concerns the problem of generating reduced dynamic thermal models whose elements have physical interpretation. The compact models of an electronic system are generated here based on the analysis of the time constant spectra of system transient thermal responses. The proposed method is illustrated on a practical example of an integrated power amplifier with a heat sink. The experiments demonstrate the influence of contact resistance and cooling conditions on the resulting values of thermal model elements.     

Novel dual discounting functions for the Internet shopping optimization problem: new algorithms

One of the very important topics in discrete optimization, motivated by practical applications, is Internet shopping, which is becoming increasingly popular each year. More classical versions of the Internet shopping optimization problem (ISOP) are closely related to the facility location problem and some scheduling problems and have been intensively studied in the literature. In this paper, extensions of the problem are defined and studied. The issue is to buy all the necessary products for a minimum total possible price. This includes all prices of products as well as shipping costs. Studies in this paper include the ISOP with price sensitive discounts and a newly defined optimization problem: the ISOP including two different discounting functions, namely a shipping cost function as well as a price discounting function. First, these are formulated as mathematical programming problems. Then, some algorithms are constructed and extensively tested in a computational experiment.