bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffusion of knowledge in the biotechnology sector
Authors: Niklewicz-Pijaczyńska Małgorzata
Published: July 2018

The aim of the paper is to analyze the use of existing legally protected solutions an. publications made available through patent systems for the development of further biotechnological inventions. For its implementation, was conducted research based on the so-called patent citations of two kinds - to literature and previously published, other patents. For the needs of the paper, technical documentation of 88 patents in the resources of the Polish Patent Office and Espacenet was analyzed. The study includes 40 Polish biotechnology companies with significant innovation activity. The results of the conducted research allow to formulate two conclusions. First, the knowledge obtained from patent resources plays an important role in the innovation process of inventions in the biotechnology sector. Secondly, this knowledge is characterized by a high degree of internationalization, first of all are cited foreign inventions and source literature, domestic citations appear relatively rarely. Among observed references, citing American achievements plays a dominant role – this applies to both literature and inventions, which suggests that the US patent system is the main source of patent knowledge for Polish biotechnology companies.
Simulation studies of storm water drainage in Wrocław
Authors: Nowakowska Monika
Published: July 2018

In the paper were made the verification of the operation of a rainwater drainage system in the residential communities of Gaj and Tarnogaj in Wrocław, carried out in the hydrodynamic model using SWMM software. There were used two criterial precipitation: Euler’s model (with a frequency of C = 3 years) and the actual precipitation (C = 5 years). The criteria of overloading the system was the specific flood volume (SFV). For both cases of precipitation load of catchment, the simulated calculations showed the occurrence of outflows from the channels. Due to the value of SFV indicator (respectively: 19 m3/ha and 42,9 m3/ha), it was found that the tested system needs modernization, therefor acceptable instantaneous water level above the maximum water impoundment were more often than 1 per 3 years, which leads to overflows from channels for residential areas more often than allowed once every 20 years.
Heating and ventilation of historic churches: the University Church – case study
Authors: Pałupska Ewa , Kanaś Paulina
Published: July 2018

The paper presents the basic issues related to heating and ventilation of historic sacred buildings based on a review of available literature. It gives guidelines for designing and calculation method of useful heat demand as well as shows vulnerable issues which must be considered during designing process. The article focuses on pros and cons of warm air heating and low temperature radiant heating (“friendly heating”). The applicability of using these heating methods in the University Church in Wrocław (Poland) was considered.
Quasi-dynamic model of the energy efficiency degradation coefficient for an air-to-water heat pump
Authors: Piechurski Krzysztof , Szulgowska-Zgrzywa Małgorzata , Danielewicz Jan
Published: July 2018

Operating in part-load conditions significantly affects the energy efficiency of the air-to-water heat pumps. The currently used method of testing the devices does not provide the necessary data for estimating the degradation of the device’s efficiency in part-load operating mode. The value of the degradation coefficient Cc = 0.9 adopted in accordance with the EN 14825 standard is generally used. However, this value often does not reflect the actual degree of the COP reduction. Hence the new quasi-dynamic model and the calculation approach to the degradation coefficient were proposed. The model reflects the real and overall reduction between the full and part-load COP, not only the energy consumption in the stand-by mode. The estimation was made using the field measurement data of the air-to-water heat pump supplying heat to the low temperature installation. It has been proved that the determination of the main parameter is possible using a relatively small amount of data without losing an accuracy.
The influence of internal catalyst on exhaust emission in dynamic conditions
Authors: Pielecha Jacek , Andrych-Zalewska Monika
Published: July 2018

The article discusses the use of an internal catalyst, which allows to reduce the emission of harmful compounds during internal combustion engine operation. This is a type of exhaust aftertreatment system; however, its placement inside the combustion chamber, and thus closest to the combustion process, allows reducing the pollution at the source (the catalyst was sprayed on the glow plugs). This is necessary because vehicle pollution reduction is a key aspect of reducing the negative environmental impact of transport. The presented research results are a part of a wider research scheme, on the evaluation of the internal catalyst impact in various engine operating conditions – starting from static tests (on an engine dynamometer), through dynamic dynamometer tests, and ending with vehicle road tests in real driving conditions. The use of an internal catalyst during dynamic tests results in a few percent reduction in the mass of carbon monoxide, hydrocarbons, carbon dioxide and the number of particulates in the considered measurement test. It is technically possible to introduce this kind of a technical solution in most vehicles with Diesel engines, thus resulting in improved ecological properties of internal combustion engines.
Computational modeling of gas mixture dispersion in a dynamic setup – 2d and 3d numerical approach
Authors: Polanczyk Andrzej , Salamonowicz Zdzisław
Published: July 2018

The aim of the study was to prepare a mathematical model of gas mixture dispersion with the use of Computational Fluid Dynamic (CFD) technique. Three dimensional chlorine dispersion in a dynamic setup with the use of Volume of Fluid model (VOD) model was applied. The area of investigation was equal to 0.1km2and the high of the mathematical domain was equal to 50m. Atmosphere was considered in two stages: as one direction of wind flow and no wind. Comparison of constant and dynamic conditions indicated high impact of wind. For the windless case circular profile of chlorine concentration around dispersion source was observed. While, for the wind application the main chlorine concentration moved ahead the source of dispersion.
Configuration of a pilot station in a technological investigation of groundwater treatment
Authors: Pruss Paweł , Pruss Alina , Komorowska-Kaufman Małgorzata
Published: July 2018

The purpose of pre-design technological investigations is to define the water treatment technology for a new or existing water treatment plant. The investigation is performed on model-scale equipment, making sure that the results can be extrapolated to the technological scale. The investigation should allow for the determination of unit process parameters and ensure the desired outcome i.e. treated water meeting the applicable quality standards. Indirectly, the investigation results can also be used as a basis for defining the estimated scope of the investment, the costs of its execution and the future equipment operating costs. Technological investigations are carried out on the grounds of existing or future treatment plants in order to take into account the variable composition and quality indicators of the raw water to be treated. The pilot station, being the main element of the technological investigation, should be designed, built and operated with a view to the possibility of formulating further design guidelines after the study is completed. In this article, the authors share their experience related to the configuration of a pilot station used in an investigation of a groundwater treatment technology.
Examination of the influence of macro and microscopic parameters of limestone on the effectiveness of gas phase desulphurisation according to the method of wet limestone
Authors: Romanik Elżbieta
Published: July 2018

The essence of the research was to develop a correlation dependence between the degree of limestone grinding and the efficiency of boiler flue gas desulfurization. The design of the Installation of Flue Gas Desulfurization (FGD) in the slurry of ground limestone begins with the assumption (based on literature data or experience gained from previously completed and operated installations) of a certain pH value of this slurry in the reactor tank. The reagent is not yet indicated, its extraction location, its chemical composition, grain size and reactivity are not determined. Application practice and economics of these processes have shown that calcium reagents are the most advantageous in application because of the general availability of limestone, its large mining resources, existing infrastructure for its extraction, the network of suppliers and the purchase cost acceptable by the recipients. On a global scale, more than 90% of the flue gas desulfurization plant is treated with limestone [1]. The effectiveness of the desulfurization process is high, and some believe that the decisive influence is on the degree of limestone fragmentation dissolution rate of CaCO3 in the absorption slurry, its reactivity to absorbed SO2, the pH of the absorption slurry.
Analysis of the ground-source heat pump operation with various heat-carrier fluids in the lower heat source
Authors: Stefanowicz Ewelina , Szulgowska-Zgrzywa Małgorzata , Fidorów-Kaprawy Natalia
Published: July 2018

In the paper the analysis of the operation of ground-source heat pump with various heat-carrier fluids circulating in boreholes was made. The authors considered several aspects related to the heat-carrier fluid selection (freezing point, heat transfer capabilities, toxicity, pumping costs). The lower heat source analysis had been performed in Earth Energy Designer (EED) software. The analyses’ results reliability was assured by the ground-source model calibration made basing on the measurement data from on-site test stand. Analyses were performed for four heat-carrier fluids (two kinds of propylene glycol solutions – standard and with lower viscosity, water and nanofluid (water + CuO)) and in four variants of thermal load (design and actual loads both with and without active regeneration). It had been concluded that temperature of none of the fluids would drop under 0°C if the system was operated under actual thermal load. For design thermal load there would be a risk of the water freezing but it may be minimized by active regeneration or lower heat source enlargement by 20% (in analyzed case) each rising the mean fluid temperature by around 1.0-1.5 K. The use of other fluid in place of standard propylene glycol solution will give pumping energy savings.
Air leakage modelling and its influence on the air quality inside a garage
Authors: Szczepanik-Ścisło Nina , Ścisło Łukasz
Published: July 2018

The problem of poor air quality due to increased airtightness of dwellings is a growing global problem. What is more, studies have shown that leakages of contaminants from garages occur to the attaching buildings. For these reasons to topic of the study was to see how increased airtightness influenced the air quality of a garage attached to a house and how it affected the contaminant flow into the house. The garage was equipped with an outlet mechanical vent. Three cases were taken under consideration: without any additional sealing, using a gasket on the garage door and using a gasket on both the garage and house door. The results of the study showed that the increased airtightness increases the concentration of contaminants inside the garage as well as the CO2 concentration flowing into the house. The air flow was disturbed and the contaminants did not flow freely to the outlet causing their dispersion inside of the garage. Such situations may be harmful to human health and should be prevented.
Formaldehyde removal by the internal wall paint – preliminary study
Authors: Szczurek Andrzej , Zajiczek Żaneta , Sibilak Dawid , Maciejewska Monika
Published: July 2018

Formaldehyde is an important indoor air pollutant. It is released mainly from building materials and consumer products. This contaminant has been recognized as having negative effect on humans. Recently, there are developed methods of reducing its emission as well as removal from indoor air. An example of the last approach is the functionalisation of interior wall paints. The influence of such paint on indoor air was preliminarily examined in this work. The obtained results show that, during intermittent exposures, responses of formaldehyde measurement device were lower in the room painted with functionalised paint compared with the room painted using traditional formula paint. This outcome was statistically significant in 67% of the examined cases at the significance level α=0.01. It was found that the serious problem associated with determining the influence of functionalised paint on indoor air, in real conditions, is the low level of formaldehyde concentrations, compared with the detection limit and accuracy of the available measurement devices.
Air trapping problem during infiltration on the large areas
Authors: Tisler Witold , Szymkiewicz Adam
Published: July 2018

The process of flow modeling in unsaturated porous medium is often found in many fields of sciences: geology, fluid mechanics, thermodynamics, microbiology or chemistry. Problem is relatively complicated due to complexity of the system which contains three phases: water, air and soil skeleton. The flow of water in such a medium can be described using two-phase (2PH) flow formulation, which accounts the inflow of air and water phases, or with simplified model known as Richards (RE) equation where only water flow is taken into account. In many well known programs available in the market (like SeepW, STOMP) the primary interest is only the water flow and the flow of air is omitted. As a result Richard equation in used more often. It’s main assumption is that pore air is continuous and has connection with atmospheric air which is equivalent to infinite mobility of the air phase during all simulation. This paper presents a brief review of the influence of the air phase in soil on water flow and pore pressure generation, with focus on applications related to infiltration process occurring in the large areas. An irrigation effect of rice fields with shallow water table has been investigated. To assess the impact of the gas phase various lengths of the infiltration zone have been considered. Numerical simulations are carried out to investigate the differences between the Richards equation and the two-phase flow model, using an in-house code based on the finite volume method.
The use of the SCADA system in the monitoring and control of the performance of an autonomous hybrid power supply system using renewable energy sources
Authors: Trzmiel Grzegorz , Łopatka Maciej , Kurz Dariusz
Published: July 2018

The paper touches upon the current issues related to the use of visualisation, control and archiving systems (SCADA) in hybrid power supply systems, based on the example of an installation that uses the energy of the sun and wind. The article contains an exemplary design of an autonomous hybrid power supply system and the SCADA system implemented in the Vijeo Citect environment. The major focus is on the presentation of the essential and the most frequently used SCADA system functionalities in terms of the monitoring and control of this type of power supply systems.
The slotted – displacement ceiling diffuser as an alternative to the organization of down – up air exchange in rooms with computer equipment
Authors: Zając Agnieszka
Published: July 2018

The article analyses heat loads occurring in public utility rooms with computer or multimedia equipment. Attention has been paid to the possibility of using down – up type (displacement ventilation, DV) and up – up type (mixing ventilation, MV) of air exchange. The design of the slotted – displacement ceiling diffuser is presented. The results of measurements in non-isothermal conditions in the form of air flows in the area of its operation are provided. The graphs show the graphical distribution of velocities and air temperatures in the vertical plane passing through the transverse axis of the special diffuser. The study of the behavior of the stream flowing out of the diffuser was only in the scope of work. The velocity and air temperature distribution over the heat sources, which were located away from the diffuser, next to the external walls, was not studied. The focus was on three representative airflows of supply air and the behaviour of the air stream during cooling was presented.
Research on Motor Drive Load Simulator Based on Model Reference Adaptive Control
Authors: Shui Yang , Wei Jianli , Yan Jie
Published: July 2018

The electric motor drive load simulator can simulate the hinge torque of the steering gear during the flight of the aircraft, which is one of the key equipment of the servo test. This paper bases on the composition and working principle of the electric load simulator, and based on the Narendra model reference adaptive control theory, the reference model of the controlled object is designed. Considering the large step disturbance of steer gear, the load simulator system the paper presented is simulated. The results show that the model can increase the bandwidth of the load system from 20 Hz to 30 Hz, realize fast, high-precision control of the electric load simulator, and improve the system's anti-perturbation performance effectively.
Analysis of Complex Typography Modulating on Internal Wave's Generation and Propagation
Authors: Gao Guoxing , Fan Lei , Wang Huigang
Published: July 2018

We use a non-hydrostatic numerical simulation based on incompressible Navier-Stokes equations to model the generation and evolution of nonlinear internal waves formed as a result of the interaction with double-ridge topography. By employing an analysis on the different-time distribution of density field, related-vorticity field which came from different profile condition of second sill, we can find and quantify the relation between the arriving time and intensity with the second sill parameter such as the depth and extensional factors. The results and progression of the internal wave's generation and propagation show the complexity, and one of the important factors is deriving from the modulating action on the state of the internal waves initial exciting from the first sill. We also present the case of coexist and evolution of "quick wave" and "slow waves". This study to reveal the ocean internal waves generated transmission mechanism is of important value.
Personalization Method for HRTF Based on Multi-Dimensional Physiological Parameters
Authors: Huang Wanqiu , Zeng Xiangyang , Wang lei
Published: July 2018

Head-Related Transfer Function (HRTF) is the most important factor to achieve Auditory Space Modeling(ASM). HRTF has many applications in the areas of room acoustic modeling, spatial hearing and multimedia. For the reason that HRTF is related to the location and frequency of sound source and the physiological structures of the listener, customization of HRTF becomes the bottle-neck problem of the research and application of ASM. This paper, based on the measured data offers the personalization method of the HRTF based on the multi-dimensional physiological parameters, and the method is verified through the spectral distortion and the subjective auditory localization experiments. The results show that database matching can obtain the personalized HRTF efficiently and in the spatial hearing experiment the personalized HRTF can reduce the front-back confusion of auditory localization and improve the accuracy.
A Method of Objects Classification Based on Learning and Visual Perception
Authors: Li Na , Zhao Xinbo , Yang Yongjia , Zou Xiaochun
Published: July 2018

Objects classification is one of the most significant problems in computer vision. For improving the accuracy of objects classification, we put forward a new classification method enlightened the whole process that human distinguish different types of objects. Our method mixed visual saliency model and CNN, is more close to human and has apparently biological advantages. Firstly, we built an eye-tracking database to learn people visual behaviors when they classify various objects and recorded the eye-tracking data. Secondly, this database is used to train a learning-based visual attention model, which is based on low-level (e.g., orientation, color, intensity, etc.) and high-level (e.g., faces, people, cars, etc.) image features to analyze and predict the human's classification RoIs. Finally, we established a CNN framework to classify RoIs. The results of the experiment showed our attention model can determine saliency regions and predict human's classification RoIs more precisely and our classification method improved the efficiency of classification markedly.
Research on Transient High-Speed Dynamical Balancing of Power Turbine Rotor
Authors: Deng Wangqun , Fu Chao , Yue Cong
Published: July 2018

A novel transient high-speed flexible rotor balancing method is derived and the transient run-up response information based balance method is used to balance a power turbine rotor of turboshaft engine. The balance efficiency is studied systematically to prove its robustness under two disturbance factors, i.e., random disturbed rotating speed and noise polluted vibration signal. Results show that the transient balance method can achieve satisfactory balance efficiency on real rotors. The disturbances have influence on the identification accuracy of the equivalent unbalance, but the robustness is good on most cases and it is a suitable technology for real applications.
Reliability, Validity, and Responsiveness of the Chinese Version of the Knee Injury and Osteoarthritis Outcome Score (KOOS) in Patients with Anterior Cruciate Ligament Reconstruction in Mainland China
Authors: Zhang Qi-Hao , Du Shi-Xin , Zheng Gui-Zhou , Chang Bo , Xie Da , Lin Fei-Xiang , Xie Peng , Yu Guo-Yong , Hu Qin-Xiao , Liu De-Zhong , Li Xue-Dong
Published: July 2018

Objective The aim of this study was to perform a cross-cultural adaption of the KOOS into Chinese and to evaluate its psychometric properties in patients with anterior cruciate ligament reconstruction (ACL reconstruction) in mainland China.

Design A cross-sectional study.

Setting Patients completed the Chinese version of the KOOS and the SF-36 questionnaire three times. We evaluated the reliability, checked the validity, and assessed the responsiveness.

Participants A total of 42 patients who had undergone ACL reconstruction.

Main Outcome Measures The results of the questionnaire survey.

Results The Chinese version of the KOOS was well accepted, with ideal test-retest reliability and internal consistency. The test-retest reliability was significant, with high ICC values ranging from 0.888 to 0.941. Additionally, we found that the internal consistency was adequate, with Cronbachʼs alpha coefficient ranging from 0.740 to 0.975. All a priori hypotheses were supported by a high correlation between the KOOS and SF-36. Furthermore, responsiveness was demonstrated since the ES and SRM between subscales following ACL reconstruction was found in the expected pattern.

Conclusions The Chinese version of the KOOS showed psychometric properties demonstrating acceptable reliability and validity similar to the original version. We conclude that the Chinese version is a reliable and valid instrument for research and clinical assessments of ACL reconstruction patients in mainland China.
Behandlung HPV-assoziierter analer Läsionen bei HIV-positiven Patienten – chirurgische Abtragung vs. topische Therapie mit Imiquimod
Authors: Websky Martin W. von , Wesselmann Paul C. , Schwarze-Zander Carolynne , Vilz Tim Oliver , Stoffels Burkhard , Boesecke Christoph , Rockstroh Jürgen , Kalff Jörg C. , Pantelis Dimitrios
Published: July 2018

Hintergrund Regelmäßige proktologische Untersuchungen sind bei HIV+-Patienten aufgrund häufiger anorektaler Erkrankungen erforderlich. Insbesondere HPV-assoziierte Läsionen wie Condylomata acuminata (C. ac.) und anale Dysplasien (AIN) werden sowohl mit operativen Verfahren als auch mit topischer Therapie behandelt.

Ziel der Arbeit Es sollte untersucht werden, ob sich chirurgische Abtragung und topische Therapie mit Imiquimod bez. Heilungsraten und Outcome bei HPV-assoziierten analen Läsionen unterscheiden und ob ein synergistischer Effekt vorliegt.

Material und Methoden Es wurden bei 97 HIV+-Patienten alle proktologischen Untersuchungen und Therapiemaßnahmen über einen Zeitraum von 10 Jahren (11/2004 – 11/2015) retrospektiv untersucht. Insbesondere wurden Diagnose und Therapie von HPV-assoziierten analen Läsionen mit klinischem Outcome nach chirurgischer Abtragung und topischer Therapie mit Imiquimod analysiert.

Ergebnisse Bei 53/97 (54%) HIV+-Patienten wurden HPV-assoziierte anale Läsionen festgestellt. Das mittlere Patientenalter betrug 41,0 ± 11,6 Jahre. Die HIV-Erkrankung war bei ca. der Hälfte der Patienten unter cART gut eingestellt (52 Patienten mit Viruslast < 40 Kopien [53,6%]). Im Verlauf wurden bei 7/53 Patienten mit C. ac. auch Low-Grade- und bei 18/53 Patienten High-Grade-AINs diagnostiziert. Eine vollständige Remission von C. ac. bzw. AIN nach einer Behandlung von 4 Wochen wurde als Erfolg gewertet. Die Erfolgsquote lag bei der Behandlung von C. ac. mit Imiquimod bei 5/25 (20,0%) vs. OP* 30/57 (52,6%, Mann-Whitney-U-Test p < 0,05) vs. OP+Imiquimod bei 7/15 (46,7%). Die Erfolgsquote lag bei der Behandlung von AIN mit Imiquimod bei 4/24 (16,7%) vs. OP* bei 47/83 (56,7%, Mann-Whitney-U-Test p < 0,05) vs. OP+Imiquimod bei 9/21 (42,8%). Es traten bei 7/92 Eingriffen chirurgische Komplikationen auf, davon 4 geringgradige und 2 signifikante Blutungen sowie eine Analvenenthrombose. Bei Imiquimod-Behandlung wurden lediglich einzelne Hautirritationen dokumentiert.

Diskussion Eine operative Erstbehandlung von HPV-assoziierten analen Läsionen bei HIV+-Patienten ist einer topischen Therapie mit Imiquimod im Kurzzeitverlauf überlegen. Ein synergistischer Effekt konnte nicht festgestellt werden. Aufgrund der vorliegenden Ergebnisse unserer Studie empfehlen wir die operative Abtragung der HPV-assoziierten Läsionen bei HIV+-Patienten.
Comparison of the Actions of Thrombin and the Thrombin-Like Venom Enzymes Ancrod and Batroxobin
Authors: Aronson D. L
Published: July 2018

Thrombin acts on several coagulant proteins to produce products with physiologic, pharmacologic and pathologic potential. The most sensitive thrombin substrate seems to be factor VIII. Some thrombin dependent reactions studied in vitro and proposed as control reactions seem too insensitive to the action of thrombin to be of in vivo significance.

The only enzymic reaction the thrombin-like venom enzymes, Ancrod and Batroxobin, have in common with thrombin is the removal of fibrinopeptide A.
Molecular Size Distribution of Fibrinogen Derivatives Formed in Vitro and in Vivo: a Chromatographic Study
Authors: Donati M. B , Verhaeghe R , Culasso D. E , Vermylen J
Published: July 2018

Using gel chromatography, fibrinogen derivatives present in purified systems or in biological fluids were separated and partially characterized. Eight groups of fibrinogen derivatives could be separated by gel filtration through 6% agarose in large columns, four with an elution volume smaller and four groups with an elution volume larger than that of fibrinogen. Careful calibration of the column allowed estimation of the diffusion coefficients of some of the derivatives and, thus, comparison with derivatives previously identified. Three, rather than two, groups of intermediate derivatives were observed during the degradation of human fibrinogen by plasmin in vitro or in vivo. One of these had a marked tendency to polymerize.

A rather distinct difference in elution pattern was found between plasma obtained during streptokinase administration and from patients with intravascular coagulation.
Fibrin Formation: The Role of the Fibrinogen-Fibrin Monomer Complex
Authors: Brass Eric P. , Forman Walter B. , Edwards Robert V. , Lindan Olgierd
Published: July 2018

The process of fibrin formation using highly purified fibrinogen and thrombin was studied using laser fluctuation spectroscopy, a method that rapidly determines particle size in a solution. Two periods in fibrin clot formation were noted: an induction period during which no fibrin polymerization occurred and a period of rapid increase in particle size. Direct measurement of fibrin monomer polymerization and fibrinopeptide release showed no evidence of an induction period. These observations were best explained by a kinetic model for fibrin clot formation incorporating a reversible fibrinogen-fibrin monomer complex. In this model, the complex serves as a buffer system during the earliest phase of fibrin formation. This prevents the accumulation of free polymerizable fibrin monomer until an appreciable amount of fibrinogen has reacted with thrombin, at which point the fibrin monomer level rises rapidly and polymerization proceeds. Clinically, the complex may be a homeostatic mechanism preventing pathological clotting during periods of elevated fibrinogen.
Family Studies of Patients with Reduced Ristocetin Aggregation and Abnormalities of Factor VIII and/or Platelet Function
Authors: Ekert H , Ananthakrishnan R , Muntz R. H , Dowling S , D’Souza S
Published: July 2018

Factor VIII procoagulant activity (VIIIc), antigen (vWa), mobility of the antigen on two dimensional Immunoelectrophoresis and platelet function were studied in 9 families with reduced ristocetin induced platelet aggregation rate (RIPA) and/or deficiency of plasma factor(s) required for ristocetin aggregation of washed normal platelets (vWf). The families could be subdivided into 4 groups. Group I showed dominant inheritance and reduced levels of VIIIc and vWa characteristic of typical von Willebrand’s disease. All patients had reduced vWf and in 7 of 10 RIPA was reduced. Group II showed normal levels of VIIIc but reduced vWa. All showed reduced vWf but RIPA was reduced in one patient only. There was a good correlation between vWf and vWa and VIIIc in both groups. The bleeding time correlated with vWf in group I but not group II. Group III showed normal or nearly normal VIIIc and vWa but there was an increased mobility of vWa compared to normals and to groups I and II. RIPA was markedly reduced as was the vWf in one patient. Group IV is represented by one child with a strong family history of bleeding, who had reduced RIPA and defective platelet release reaction. The vWf in this child was normal and the ratio between VIIIc and vWa was similar to that seen in carriers of haemophilia. This spectrum of abnormalities of ristocetin aggregation justifies the use of the term ‘von Willebrand’s syndrome’.
Bleeding in Uremic Patients after Carbenicillin
Authors: Andrassy K , Weischedel E , Ritz E , Andrassy T
Published: July 2018

Hemorrhagic diathesis was observed in patients with renal insufficiency after carbenicillin at serum levels > 300 μg/ml. Normal coagulation factors (F. I, II, V, VII, VIII, X), normal PTT, normal platelet counts, negative ethanol gelation test (fibrin monomers) were found as well as a prolongation of thromboplastin time (Quick), thrombin time, reptilase time and thrombin coagulase time. Platelet function was disturbed. In addition, the plasmatic system was involved: inhibition of fibrinogen-fibrin conversion (Belitser assay) and enhanced antithrombin III activity; in vivo the latter was ascribed to a heparin-like activity. In vitro, abnormal fibrinogen-fibrin conversion and a modified electrophoretic mobility of antithrombin III was seen: however an enhanced antithrombin III activity in vitro was not found with carbenicillin and various penicillin derivatives.

This study demonstrates that carbenicillin, in addition to its known effect on platelet function, also disturbs the plasmatic coagulation system. This additional effect of carbenicillin is clinically important since protamin chloride effectively blocks bleeding without interfering with antibacterial activity.

Both penicillin and penicillin derivatives have been shown to interfere with hemostasis and to cause clinically manifest hemorrhagic diathesis (Fleming and Fish 1947, Lurie et al. 1970a, b, McClure et al. 1970, Yudis et al. 1972, Demos 1971, Waisbren et al. 1971). Carbenicillin interferes with ADP-, collagen- or thrombin-induced platelet aggregation and with the release reaction both in vivo (McClure et al. 1970, Cazenave et al. 1973) and in vitro (McClure et al. 1970, Cazenave et al. 1973). In addition Lurie and colleagues (1970b) concluded that an inhibition of the conversion of fibrinogen to fibrin is involved although no experimental details were given. Later Brown and colleagues (1974) concluded that carbenicillin at usual dose levels “only affects the platelet component of hemostasis and has little effect on fibrin formation or other phases of coagulation in patients with normal renal function”.
Some Observations on the Preparation of Platelet-Rich Plasma
Authors: Woods Brian P. , Dennehy Angela , Clarke Noel
Published: July 2018

In order to prepare platelet-rich plasma a constant height and volume of citrated whole blood was centrifuged at different gravity forces and times. The supernatant plasmas were examined for platelet concentrations, plasma volumes and optical densities. Results are described showing that gravity force and time have an important influence on the platelet numbers and the plasma volumes recovered.

The light attenuation by different concentrations of platelets in plasma, using light path lengths of 5 mm and 10 mm, was compared. The shorter light path provides greater linearity between optical density and platelet numbers especially at higher concentrations.
Platelet Aggregation Following Defibrination with Ancrod
Authors: Lawrence Slade C , Abe Andes W , Mason Arthur D.
Published: July 2018

In vitro platelet aggregation was studied in dogs following defibrination with Ancrod. There was marked inhibition of aggregation immediately after defibrination. A gradual return toward normal aggregation was observed over the 96 hours study period, but aggregation was still abnormal at 96 hours after defibrination. There was an inverse and highly significant correlation between aggregation and fibrin degradation product level. Fibrinogen was not measurable after defibrination for the entire study period. Aggregation was thus independent of fibrinogen concentration in this study.
Physico-Chemical Explanation of Blood Cell Adhesion in Thrombus Formation
Authors: Marmur A , Ruckenstein E , Rakower S. R
Published: July 2018

A model is suggested which assumes that the rate of deposition of cells is determined both by hydrodynamic factors and by Brownian motion over the potential barrier caused by London and double-layer forces in the immediate vicinity of the deposition surface. The height of the barrier in the potential energy of interaction between blood cells and various surfaces is analyzed in relation to the physical properties of the cells, surfaces, and solutions. Based on this analysis, the adhesion of platelets to injured blood vessel walls and to non-biologic materials, the lack of adhesion of red blood cells under the same conditions, the mechanism of ADP induced aggregation and the interaction with blood flow are explained. The qualitative predictions of the model are substantiated by available experimental information. Quantitative results are presented in terms of a time constant, which typifies a period of contact with a surface, during which appreciable deposition occurs.
Effect of the Root Extract of Fagara Zanthoxyloides on Blood Coagulation
Authors: Essien E. M , Okogun J. I
Published: July 2018

The clot-promoting activity of the aqueous extract of Fagara zanthoxyloides Lam plant is described for the first time. It significantly shortened the PTT (K) of normal and factor VIII deficient plasma while it manifested no such action on factor IX-deficient plasma. This activity could be demonstrated in the residue of the lyophilized aqueous extract after its successive extraction with ether, chloroform and methanol. It could not be attributed to the purified fractions: Zanthoxylol or its modified form 3, 4-dihydro-2,2-dimethyl-2H-1 benzopyran-6-butyric acid (DBA), hesperidin, Fagaramide or the ether soluble fraction of the aqueous extract.
Plasma Factor XIII and Platelet Factor XIII in Hyperlipaemia
Authors: Cucuianu Mircea P. , Miloszewski K , Porutiu D , Losowsky M. S
Published: July 2018

Plasma factor XIII activity measured by a quantitative assay was found to be significantly higher in hypertriglyceridaemic patients (type IV and combined hyperlipoproteinaemia), as compared to normolipaemic controls. No such elevation in plasma factor XIII activity was found in patients with type IIa hyperlipaemia. Plasma pseudocholinesterase was found to parallel the elevated factor XIII activity in hypertriglyceridaemic subjects.

In contrast, platelet factor XIII activity was not raised in hyperlipaemic subjects, and plasma factor XIII was found to be normal in a normolipaemic subject with throm-bocythaemia.

It was concluded that there is no significant contribution from platelets to plasma factor XIII activity, and that the observed increase in plasma factor XII in hypertriglyceridaemia results from enhanced hepatic synthesis of the enzyme.
The Effect of the Fibrinogen Concentration and the Leukocyte Count on Intravascular Fibrin Deposition from Soluble Fibrin Monomer Complexes
Authors: Gurewich Victor , Lipinski Boguslaw , Hyde Elisabeth
Published: July 2018

Fibrin formation from fibrin monomer (FM) complexes was studied in experimental animals utilizing a previously described technique for quantitating fibrin deposition. A uniform thrombin infusion was used to produce FM, fibrinolysis being inhibited by EACA. In vivo complex formation between FM and 125I-fibrinogen was demonstrated chromatographically. A direct correlation was found between blood fibrinogen concentration and fibrin deposition in organs. By contrast, an inverse correlation between fibrinogen concentration and both enzymatic or non-enzymatic fibrin formation was found in vitro. The mechanism by which fibrinogen potentiates FM precipitation in vivo could not be explained by coprecipitation of fibrinogen in the complex which could not be demonstrated. The inhibitory effect of HN2 on fibrin deposition despite the associated hyperfibrinogemia induced by this drug is believed to underscore the importance of leukocytes in certain types of fibrin deposition. A correlation between the leukocyte count and fibrin formation from FM was also found. It was concluded that the risk of intravascular fibrin deposition is increased by a raised fibrinogen level especially when accompanied by leukocytosis.
Hirudin C-Terminal Fragments lnhibit Thrombin Induced Neutrophil Chemotaxis
Authors: Rowand Judith K , Marucha Philip , Berliner Lawrence J
Published: July 2018

Since native hirudin blocks the thrombin induced chemotaxis response of neutrophils, we examined whether hirudin C-terminal peptides were also capable of this inhibition. The studies showed that thrombin induced human neutrophil chemotaxis was effectively blocked by the C-terminal hirudin peptide analogs, Gly-Asp-Phe-Glu-Glu-Ile-Pro-Glu-Glu-Tyr-Leu-Gin (12-mer[54-65]) and Thr-Pro-Lys-Pro-Gln-Ser-His-Asn-Asp-Gly-Asp-Phe-Glu-Glu-Ile-Pro-Glu-Glu-Tyr-Leu-Gln (21-mer[45-65]). Furthermore, neither peptide had an effect on formyl-L-methionyl-L-leucyl-L-phenylalanine induced chemotaxis. The results suggest that binding of the hirudin C-terminal peptides block the thrombin chemotactic domain.
Hematological Causes of Venous Thrombosis in Young People: High Incidence of Myeloproliferative Disorder as Underlying Disease in Patients with Splanchnic Venous Thrombosis
Authors: Teofili Luciana , De Stefano Valerio , Leone Giuseppe , Micalizzi Paola , lovino Michela Stefania , Alfano Generoso , Bizzi Bruno
Published: July 2018

Thrombotic events occur frequently in myeloproliferative disorders, namely polycythaemia vera and essential throm-bocythaemia. Standard diagnostic criteria are designed quite stringent, so that a number of patients could be underdiagnosed. Spontaneous erythroid colonies formation from bone marrow or peripheral blood in the absence of exogenous erythropoietin is considered a reliable index of myeloproliferative disorder even at early stages. Endogenous erythroid colonies (EECs) formation was assessed in 43 patients having recently suffered from venous thrombosis prior to 45 years and without a previous diagnosis of hematological disease favouring thrombosis. A screening for coagulative abnormalities associated with thrombophilia was also carried out: in 5 patients (11.6%) a plasmatic thrombogenic defect was found (quantitative deficiency of antithrombin III, 1 case, protein C, 2 cases, protein S, 1 case, and plasminogen, 1 case). In 10 patients (2 males and 8 females) (23.2%) EECs assay was positive, allowing diagnosis of myeloproliferative disease even though 7 of them did not fulfill standard diagnostic criteria. In the other 3 patients who met the criteria for diagnosis of overt myeloproliferative disease the thrombotic event was the inaugural manifestation. In all these EECs-positive patients thrombosis involved mesenteric and portal veins (n = 4), hepatic veins (n = 3), portal vein (n = 2), mesenteric vein (n = 1). One of them was simultaneously affected from congenital protein C deficiency. Thus latent or atypical forms of myeloproliferative disease as well as the overt stages were the most frequent recognized cause of splanchnic venous thrombosis, accounting for 55% of the cases of our series. On the contrary no EECs-positive subject was found among the 25 patients with other sites of thrombosis. It is concluded that a myeloproliferative disorder should be carefully considered in young patients with splanchnic venous thrombosis and a thorough investigation should include evaluation of EECs.
Experimental Carotid Stenosis and Endothelial Injury in the Rabbit: An In Vivo Model to Study Intravascular Platelet Aggregation
Authors: Golino Paolo , Ambrosio Giuseppe , Pascucci Immacolata , Ragni Massimo , Russolillo Enrico , Chiariello Massimo
Published: July 2018

Previous studies have shown that experimental canine coronary artery stenosis associated with endothelial injury results in a typical pattern of coronary flow characterized by gradual decreases in coronary flow to almost zero values followed by restorations of flow to normal values. This pattern of flow, called cyclic flow reductions (CFRs), is the consequence of recurrent platelet aggregation at the site of the stenosis and endothelial injury and subsequent dislodgement of the thrombus. In the present study, platelet activation and aggregation in vivo was induced by placing an external constrictor around carotid arteries with endothelial injury in anesthetized rabbits. Carotid blood flow velocity was measured continuously with a Doppler flow probe positioned proximally to the constrictor. After placement of the constrictor, CFRs developed in 14 of 14 rabbits with a mean frequency of 16.5 ± 2.3 cycles/h. CFRs were observed for 30 min, and the animals were treated with either an i.v. bolus of aspirin (10 mg/kg) or R 68070 (20 mg/kg), a drug with simultaneous TxA2 synthase and TxA2/PGH2 receptor blocking properties. Aspirin completely inhibited CFRs in 4 of 7 rabbits, whereas R 68070 eliminated CFRs in 7 of 7 animals. In the 3 animals that did not respond to aspirin, administration of ketanserin (0.25 mg/ kg i.v.), a selective serotonin S2 receptor antagonist, completely abolished CFRs. Both aspirin and R 68070 resulted in a marked reduction in serum TxB2 formation and in a complete inhibition of ex vivo platelet aggregation in response to arachidonic acid, whereas aggregation in response to U46619, a TxA2 mimetic, was inhibited only in R 68070-treated rabbits. We conclude that 1) CFRs develop in rabbit carotid arteries at sites of experimental stenosis and endothelial injury; 2) this model can be usefully employed to study platelet aggregation and platelet-vessel wall interaction in vivo and to test the efficacy of antiplatelet interventions.
Absence of the Largest Platelet-von Willebrand Multimers in a Patient with Lactoferrin Deficiency and a Bleeding Tendency
Authors: Parker Robert I , McKeown Laurie P , Gallin John I , Gralnick Harvey R
Published: July 2018

We have studied a young male with lactoferrin deficiency and a bleeding tendency responsive to cryoprecipitate. This child has had increased bleeding following surgical procedures and a variably prolonged template bleeding time. The patient has a normal platelet count, normal in vitro platelet ATP secretion and aggregation in response to a variety of agonists, and normal concentration of plasma-von Willebrand factor ristocetin cofactor activity and antigen. Analysis of plasma-vWf multimers by agarose gel electrophoresis consistently demonstrated a subtle decrease in the largest vWf multimers. In contrast, analysis of the patient’s platelet-vWf revealed normal vWf:Ag, decreased vWf ristocetin cofactor activity, and a striking absence of the high and intermediate size molecular weight vWf multimers. Analysis of surface bound platelet-vWf demonstrated normal amounts on the surface of unstimulated platelets, but after thrombin stimulation the platelet-vWf surface expression did not increase. This lack of increased platelet-vWf surface expression resulted from decreased binding of secreted platelet-vWf to be surface of stimulated platelets. These data suggest that the patient’s bleeding tendency may be related to a defect in his platelet-vWf structure and/or mobilization. This case represents a unique demonstration of an abnormality of platelet-vWf in the presence of normal plasma-vWf, and supports the data indicating an important role for platelet-vWf in primary hemostasis.
Hypofibrinolysis in Patients with a History of Idiopathic Deep Vein Thrombosis and/or Pulmonary Embolism
Authors: Grimaudo Vito , Bachmann Fedor , Hauert Jacques , Christe Maria-Adele , Kruithof Egbert K O
Published: July 2018

An impaired fibrinolytic activity after a venous occlusion test is the most common abnormality associated with thomboembolic disease. To better characterize the causes of abnormal responses we have measured different fibrinolytic parameters, before and after 10 and 20 min of venous occlusion, in 77 patients with a history of idiopathic deep vein thrombosis and/or pulmonary embolism and in 38 healthy volunteers.

The patients had a lower mean fibrinolytic response to venous occlusion than the controls and higher antigen levels of tissue-type plasminogen activator (t-PA: Ag) and plasminogen activator inhibitor type 1 (PAI-1:Ag). Before venous occlusion, PAI-1 levels were at a molar excess over those of t-PA in all patients and controls. After 20 min of venous occlusion, the release of t-PA from the vascular endothelium resulted in a molar excess of t-PA over PAI-1 in the majority of controls (72%) but only in a minority of patients (39%).

To identify patients with fibrinolytic abnormalities, reference intervals (RI) for fibrinolytic activity, t-PA:Ag and PAI-1:Ag were established in healthy controls. None of the patients had low levels of t-PA:Ag, but 17 (22%) had elevated PAI-1:Ag levels before venous occlusion and 12 (16%) exhibited low fibrinolytic activity after 20 min of venous occlusion. Ten of these were among the 17 subjects with high PAI-1: Ag levels before venous occlusion. Thus, the measurement of PAI-1:Ag levels before venous occlusion (i.e. in samples taken without any stimulation) is a sensitive (83%) and specific (89%) assay for the detection of patients with an impaired fibrinolytic response to venous occlusion.