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The model of supercontinent cycles is revisited on the basis of reevaluation of existing ideas on the geodynamics and tectonics of granulite gneiss belts and areals. Granulite-gneiss belts and areals of a regional scale correspond to mantle-plume (superplume) activity and form the major components of intracontinental orogens. The evolution of geodynamic settings of the Earth’s crust origin can be imagined as a “spiral sequence”: (1) interaction of mantle plumes and “embryonic” microplate tectonics during the Paleo- Mesoarchean (~3.80-2.75 Ga); (2) plume-tectonics and local plume-driven plate-tectonics within supercontinent during Neoarchean and Proterozoic (~2.75-0.85 Ga); (3) plate tectonics in the Phanerozoic along with a reduced role of mantle plumes starting from ~0.85 Ga. [ABSTRACT FROM AUTHOR]

In the Salma eclogite of the Belomorian eclogite province, a dumortierite-phengite-corundum-bearing quartz-feldspar rock has been studied: its primary HP mineral paragenesis included garnet, phengite, and quartz. The phengite-quartz rocks were formed during dehydration and/or melting of boroncontaining rocks when they were dipped in the Meso- Neoarchaean subduction zone to a depth of not less than 70 km. As a result of the subsequent superimposed high-temperature metamorphic events under PT conditions of high-pressure granulite facies, the phengite in quartz underwent incongruent dehydration melting with formation of complex polymineral pseudomorphs, consisting of feldspars, biotite, newly formed muscovite, kyanite, corundum, and dumortierite. New estimates of the metamorphic temperature (850-900°C according to the melting reactions of phengite and the dumortierite field of stability; about 1000°C by the reintegrated composition of feldspar-mesoperthite) that affected the HP parageneses of Salma eclogitized rocks are at least 50-100°C (or even more) higher than them estimated earlier. [ABSTRACT FROM AUTHOR]

The eclogites exposed along northeastern boundary of the Belomorian orogen in the eastern Fennoscandian Shield were formed as a result of Mesoarchean–Neoarchean subduction and collision. As has been shown previously, the common protolith of the Salma-type subduction-related eclogite was oceanic layered gabbro. In this paper, we characterize eclogites formed from volcanic–sedimentary rocks of the upper oceanic crust, which comprised pillow lavas and associated aluminous sediments that filled the interpillow space intercalated with lava flows. As a result of eclogite facies metamorphism, the aluminous sediments have been transformed into coarse-grained garnet–phengite–quartz rocks under pressure no lower than 21 kbar at a temperature of ~650 °C. Alternatively, we cannot rule out the possibility that the garnet–phengite–quartz veins represent solidified felsic melts that were produced by melting of boron-bearing hydrothermally altered oceanic crust in the subduction zone. During transfer to the upper crust under high-P granulite facies conditions, phengite underwent incongruent melting with formation of complex polymineralic pseudomorphs consisting of feldspar, biotite, muscovite and kyanite with corundum and dumortierite. The peak of high-T metamorphism during exhumation of the eclogites is estimated at 850–900 °C, i.e. at least 50–100 °C higher than previous estimates. [ABSTRACT FROM AUTHOR]

The Neoarchean and Paleoproterozoic granulite-gneiss complexes of the northern East European Craton, including their tectonic setting, accompanying igneous and sedimentary rocks, character of metamorphism and deep structure are considered in this paper. A similar approach was applied to the description and interpretation of the granulite-gneiss complexes of the Grenville-Sveconorwegian Orogen localized in the present-day structure of the European and North American continents. One of the most important results of this study is the recognition of a new type of tectonic structures called intracontinental oval orogens. These orogens were formed in the inner domain of the Neoarchean-Proterozoic supercontinent (2.8-0.85 Ga), which is called Lauroscandia. The extensional setting, which was initiated by a series of mantle plumes, locally passing to spreading but did not lead to the eventual breakup of the supercontinent and was followed by intracontinental collisional compression accompanied by closure of short-lived local oceans, subduction, and obduction. The Neoarchean and Proterozoic granulite-gneiss belts and areas of the East European Craton are components of the Karelian-Belomorian, Kola, Volgo-Uralia, Lauro-Russian, and Grenville-Sveconorwegian intracontinental oval orogens formed in the inner domain of Lauroscandia as a result of mantle-plume and plate-tectonic processes initiated by mantle superplumes. The geodynamic settings and tectonic processes in the Neoarchean-Proterozoic supercontinent differed markedly from both the Archean tectonics of miniplates and the Phanerozoic plate tectonics. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Do plasma levels of stromal cell-derived factor-1 (CXCL12, sometimes termed SDF-1) and the numbers of circulating endothelial progenitor cells (EPCs), EPC colony-forming units (EPC-CFU) and mature endothelial cells (ECs) differ between women with idiopathic heavy menstrual bleeding of endometrial origin (HMB-E) and controls and are they related to plasma levels of other angiogenic growth factors? SUMMARY ANSWER Angiogenesis is altered in women with HMB-E, characterized by a reduction in mean plasma levels of CXCL12, a low number of EPCs-CFUs and a high level of circulating ECs. WHAT IS KNOWN ALREADY Plasma levels of CXCL12 are significantly higher during the proliferative than the secretory phase of the menstrual cycle in healthy women and exhibit a negative correlation with blood EPC-CFUs. STUDY DESIGN, SIZE, DURATION A prospective cohort study in a university hospital setting. Between 2008 and 2009 10 HMB-E patients were recruited from Karolinska University Hospital. Ten healthy women were also included in the analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS Ten healthy control women and 10 HMB-E patients, all with regular menstrual cycles, provided 4 blood samples during a single menstrual cycle: 2 in the proliferative phase, 1 at ovulation and 1 in the secretory phase. We assessed plasma levels of CXCL12, vascular endothelial growth factor A165 (VEGFA), basic fibroblast growth factor (bFGF) and granulocyte and granulocyte–macrophage colony-stimulating factors by ELISA. We counted circulating EPC-CFUs by culture, and ECs and EPCs by flow cytometry and immunostaining for cell surface markers. MAIN RESULTS AND THE ROLE OF CHANCE Plasma levels of CXCL12 were significantly lower in HMB-E patients compared with control women (P < 0.0001), with a significant decrease (P = 0.013) between the proliferative phase and ovulation. VEGFA showed a trend towards the same decreasing pattern as CXCL12, although not statistically significant (P = 0.086), whereas systemic VEGFA levels in control women remained unchanged across the different phases of the menstrual cycle (P = 0.473). HMB-E patients had a lower number of EPC-CFUs compared with control women (P = 0.014), with a positive correlation between the level of CXCL12 and EPC-CFUs (r = 0.428; P = 0.047). Whilst the level of circulating endothelial cells in HMB-E patients was higher than in control women, this did not reach statistical significance. In contrast, the levels of the hematopoietic/EPC marker CD34 were significantly lower in HMB-E patients than control women (P < 0.020). LIMITATIONS, REASONS FOR CAUTION Small sample, unknown source of CXCL12, unknown balance between influx and efflux of EPCs from bone marrow and to the endometrium. WIDER IMPLICATIONS OF THE FINDINGS Our results indicate that CXCL12 may play an important role in physiological angiogenesis in the endometrium, and that low and dysregulated levels of CXCL12 in women with HMB-E could affect vessel quality, integrity and repair. STUDY FUNDING/COMPETING INTEREST(S) Financial support was provided through the regional agreement on medical training and clinical research (ALF) between the Stockholm County Council and Karolinska Institutet (number 20110258). This study was also supported by grants from the Swedish Labor Market Insurance. The authors have no conflict of interest to declare. [ABSTRACT FROM PUBLISHER]

Background: The individual features of tumours are often disregarded in cohort studies. As these features may represent a source for individualised cancer treatment, it is important to develop a novel approach for their assessment.Methods: We used proteomics, systems biology, and immunohistochemistry to explore protein expression in human endometrial tumours, to identify deregulated regulatory mechanisms, and to validate observed changes in protein expression using tissue microarrays.Results: Compared with the evaluation of common tumour features, the evaluation of individual tumour features gave a more comprehensive and detailed overview of the regulatory processes in endometrial tumours. Systemic analysis of the individual proteome profiles showed that endometrial tumours employed different proteins to regulate similar functions. Comparison of our data with publicly available data sets of molecular profiling of human endometrial tumours confirmed that individual tumour features are not simply irrelevant individual variations, but are indeed important in endometrial tumorigenesis. Validation through tissue microarray investigation of MST1 and PKN1 proteins confirmed the usefulness of this approach, and suggested that MST1 and PKN1 may be considered as predictive biomarkers of endometrial cancer.Conclusion: We show that individualised profiling of endometrial tumours may deliver better insights into a tumour's physiology, thereby giving a better prediction of tumour development. Individual tumour features may also be used to tailor cancer treatment. [ABSTRACT FROM AUTHOR]

Background:The individual features of tumours are often disregarded in cohort studies. As these features may represent a source for individualised cancer treatment, it is important to develop a novel approach for their assessment.Methods:We used proteomics, systems biology, and immunohistochemistry to explore protein expression in human endometrial tumours, to identify deregulated regulatory mechanisms, and to validate observed changes in protein expression using tissue microarrays.Results:Compared with the evaluation of common tumour features, the evaluation of individual tumour features gave a more comprehensive and detailed overview of the regulatory processes in endometrial tumours. Systemic analysis of the individual proteome profiles showed that endometrial tumours employed different proteins to regulate similar functions. Comparison of our data with publicly available data sets of molecular profiling of human endometrial tumours confirmed that individual tumour features are not simply irrelevant individual variations, but are indeed important in endometrial tumorigenesis. Validation through tissue microarray investigation of MST1 and PKN1 proteins confirmed the usefulness of this approach, and suggested that MST1 and PKN1 may be considered as predictive biomarkers of endometrial cancer.Conclusion:We show that individualised profiling of endometrial tumours may deliver better insights into a tumour's physiology, thereby giving a better prediction of tumour development. Individual tumour features may also be used to tailor cancer treatment. [ABSTRACT FROM AUTHOR]

The article presents information on the eclogite bodies that are formed as a result of Meso-Neoarchean subduction of oceanic and continentalcomplexes and is located on the Southern Kola active margin along the northeastern boundary of the Belomorian accretion orogen. It informs that the eclogite province includes two types of associations, which differ in the nature of the protoliths. It further informs that the age of magmatic crystallization, eclogite metamorphism, and subsequent retrogradetransformations of mafic dykes are the most common topic of the debate.

Background: Genomic stability is one of the crucial prognostic factors for patients with endometrioid endometrial cancer (EEC). The impact of genomic stability on the tumour tissue proteome of EEC is not yet well established.Methods: Tissue lysates of EEC, squamous cervical cancer (SCC), normal endometrium and squamous cervical epithelium were subjected to two-dimensional (2D) gel electrophoresis and identification of proteins by MALDI TOF MS. Expression of selected proteins was analysed in independent samples by immunohistochemistry.Results: Diploid and aneuploid genomically unstable EEC displayed similar patterns of protein expression. This was in contrast to diploid stable EEC, which displayed a protein expression profile similar to normal endometrium. Approximately 10% of the differentially expressed proteins in EEC were specific for this type of cancer with differential expression of other proteins observed in other types of malignancy (e.g., SCC). Selected proteins differentially expressed in 2D gels of EEC were further analysed in an EEC precursor lesion, that is, atypical hyperplasia of endometrium, and showed increased expression of CLIC1, EIF4A1 and PRDX6 and decreased expression of ENO1, ANXA4, EMD and Ku70.Conclusion: Protein expression in diploid and aneuploid genomically unstable EEC is different from the expression profile of proteins in diploid genomically stable EEC. We showed that changes in expression of proteins typical for EEC could already be detected in precursor lesions, that is, atypical hyperplasia of endometrium, highlighting their clinical potential for improving early diagnostics of EEC. [ABSTRACT FROM AUTHOR]

Background:Genomic stability is one of the crucial prognostic factors for patients with endometrioid endometrial cancer (EEC). The impact of genomic stability on the tumour tissue proteome of EEC is not yet well established.Methods:Tissue lysates of EEC, squamous cervical cancer (SCC), normal endometrium and squamous cervical epithelium were subjected to two-dimensional (2D) gel electrophoresis and identification of proteins by MALDI TOF MS. Expression of selected proteins was analysed in independent samples by immunohistochemistry.Results:Diploid and aneuploid genomically unstable EEC displayed similar patterns of protein expression. This was in contrast to diploid stable EEC, which displayed a protein expression profile similar to normal endometrium. Approximately 10% of the differentially expressed proteins in EEC were specific for this type of cancer with differential expression of other proteins observed in other types of malignancy (e.g., SCC). Selected proteins differentially expressed in 2D gels of EEC were further analysed in an EEC precursor lesion, that is, atypical hyperplasia of endometrium, and showed increased expression of CLIC1, EIF4A1 and PRDX6 and decreased expression of ENO1, ANXA4, EMD and Ku70.Conclusion:Protein expression in diploid and aneuploid genomically unstable EEC is different from the expression profile of proteins in diploid genomically stable EEC. We showed that changes in expression of proteins typical for EEC could already be detected in precursor lesions, that is, atypical hyperplasia of endometrium, highlighting their clinical potential for improving early diagnostics of EEC. [ABSTRACT FROM AUTHOR]

The integral 3D model of the deep structure of the Early Precambrian crust in the East European Craton is based on interpretation of the 1-EU, 4B, and TATSEIS seismic CDP profiles in Russia and the adjacent territory of Finland (FIRE project). The geological interpretation of seismic images of the crust is carried out in combination with consideration of geological and geophysical data on the structure of the Fennoscandian Shield and the basement of the East European platform. The model displays tectonically delaminated crust with a predominance of low-angle boundaries between the main tectonic units and the complex structure of the crust-mantle interface, allowing correlation of the deep structure of the Archean Kola, Karelian, and Kursk granite-greenstone terrane with the Volgo-Uralia granulite-gneiss terrane, as well as the Paleoproterozoic intracontinental collision orogens (the Lapland-Mid-Russia-South Baltia orogen and the East Voronezh and Ryazan-Saratov orogens) with the Svecofennian accretionary orogen. The lower crustal 'layer' at the base of the Paleoproterozoic orogens and Archean cratons was formed in the Early Paleoproterozoic as a result of underplating and intraplating by mantle-plume mafic magmas and granulite-facies metamorphism. The increase in the thickness of this 'layer' was related to hummocking of the lower crustal sheets along with reverse and thrust faulting in the upper crust. The middle crust was distinguished by lower rigidity and affected by ductile deformation. The crust of the Svecofennian Orogen is composed of tectonic sheets plunging to the northeast and consisting of island-arc, backarc, and other types of rocks. These sheets are traced in seismic sections to the crust-mantle interface. [ABSTRACT FROM AUTHOR]

Background: Cytology-based diagnostics of squamous cervical cancer (SCC) precursor lesions is subjective and can be improved by objective markers.Methods: IHC-based analysis of ANXA6, HSP27, peroxiredoxin 2 (PRDX2), NCF2, and tropomyosin 4 (TPM4) during SCC carcinogenesis.Results: Expression of ANXA6, HSP27, PRDX2, and NCF2 in the cytoplasm of dysplastic cells increased from cervical intraepithelial neoplasia 2/3 (CIN2/3) to microinvasive cancer. Invasive SCC showed lower expression of TPM4 than CIN and normal epithelium. CIN2/3 with the highest sensitivity and specificity differed from normal epithelium by cytoplasmic expression of HSP27. Patients with cytoplasmic HSP27 expression in SCC deviating from that observed in normal epithelium had worse relapse-free (P=0.019) and overall (P=0.014) survival. Invasive SCC with the highest sensitivity and specificity differed from normal epithelium by expression of PRDX2 and TPM4 in the cytoplasm, from CIN2/3 by the expression of ANXA6 and TPM4 in the cytoplasm, and from microinvasive SCC by the expression of PRDX2 and ANXA6 in the cytoplasm. The number of sporadic ANXA6+ cells between the atypical cells increased from CIN2/3 to invasive SCC.Conclusion: Detection of expression changes of the proteins ANXA6, HSP27, PRDX2, NCF2, and TPM4 in SCC precursor lesions may aid current cytological and pathological diagnostics and evaluation of prognosis. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the relations of well-crystallized rocks' composition to the Sumian basaltic andesites at the Karelian craton. It mentions that the use of U-Pb SHRIMP-II ion method showed that Sumian basaltic andesites were formed in Paleoproteozoic which has a cross-cutting relations with basaltic andesites. It states that rocks which are exposed to the fine-to medium-grained amphibolites have close chemical composition and gradual transition. It says that the age value of zircons which are taken from amphibolites were determined by the precision high resolution secondary-ion micro-probe SHRIMP-II. It adds that the Gaikol intrusion emplacement into the Sumian sedimentary-volcanogenic sequences was assumed to be contributor to the zircon formation.

The article focuses on a study that examines the grounds for the existence of the chronological, structural and petrological tectonic interlinks between different manifestations of the Archaean eclogite metamorphism within the Belomorian eclogite province (BEP) in Karelia, Russia. Salma and Gridino were the two eclogite assemblages included in the BEP located in migmatized tonalite-trondhjemite-granodiorite (TTG) gneisses of the Keretian formation. It adds that the grounds for such existence may open new possibilities for the reconstruction of the geodynamic processes in relation to the history of Early Precambrian crust region and may provide appropriate concept of the Early Precambrian as a whole.

Conditioning regimens are an important issue determining the outcome of hematopoietic stem cell transplantation (HSCT). Less toxicity, early engraftment and no relapse are the aims of efficient conditioning. Our objective was to investigate the long-term effects of BU–CY and their administration order on the toxicity and chimerism in a mouse model of HSCT. Female BALB/c mice were treated with either BU (15 mg/kg/day × 4)–CY (100 mg/kg/day × 2) or CY–BU. Treated mice were transplanted with Sca-1+ cells from male BALB/c mice. Until 90 days after HSCT, the animals were monitored for body weight and analyzed for cellular phenotype of the thymus, spleen and BM, total chimerism, the spleen chimerism of DCs and T regulatory (Treg) cells, and hepatotoxicity. BU–CY and CY–BU treatments exerted comparable myeloablative and immunosuppressive effects. The long-term engraftment of donor cells in the BM and thymus regeneration showed the same features in both groups. However, the two regimens differed; in general, hepatotoxicity and chimerism of DC and Treg cells. In the long term, BU–CY, but not CY–BU caused a marked decrease in body weight and a significant increase in the activities of the liver enzymes, particularly aspartate amino transferase (AST). We conclude that the alteration of the administration order of BU–CY to CY–BU not only gives the same level of engraftment but also reduces the toxicity of the conditioning regimen that might be valuable specially in young patients who are undergoing HSCT.Bone Marrow Transplantation (2008) 41, 895–904; doi:10.1038/sj.bmt.1705996; published online 28 January 2008 [ABSTRACT FROM AUTHOR]

The evolution of the North American, East European, and Siberian cratons is considered. The Paleoproterozoic juvenile associations concentrate largely within mobile belts of two types: (1) volcanic-sedimentary and volcanic-plutonic belts composed of low-grade metamorphic rocks of greenschist to low-temperature amphibolite facies and (2) granulite-gneiss belts with a predominance of high-grade metamorphic rocks of high-temperature amphibolite to ultrahigh-temperature granulite facies. The first kind of mobile belt includes paleosutures made up of not only oceanic and island-arc rock associations formed in the process of evolution of relatively short-lived oceans of the Red Sea type but also peripheral accretionary orogens consisting of oceanic, island-arc, and backarc terranes accreted to continental margins. The formation of the second kind of mobile belt was related to the activity of plumes expressed in vigorous heating of the continental crust; intraplate magmatism; formation of rift depressions filled with sediments, juvenile lavas, and deposits of pyroclastic flows; and metamorphism of lower and middle crustal complexes under conditions of granulite and high-temperature amphibolite facies that, in addition, spreads over the fill of rift depressions. The evolution of mobile belts pertaining to both types ended with thrusting in a collisional setting. Five periods are recognized in Paleoproterozoic history: (1) origin and development of a superplume in the mantle that underlay the Neoarchean supercontinent; this process resulted in separation and displacement of the Fennoscandian fragment of the supercontinent (2.51–2.44 Ga); (2) a period of relatively quiet intraplate evolution complicated by locally developed plume-and plate-tectonic processes (2.44–2.0 (2.11) Ga); (3) the origin of a new superplume in the subcontinental mantle (2.0–1.95 Ga); (4) the complex combination of intense global plume-and plate-tectonic processes that led to the partial breakup of the supercontinent, its subsequent renascence and the accompanying formation of collisional orogens in the inner domains of the renewed Paleoproterozoic supercontinent, and the emergence of accretionary orogens along some of its margins (1.95–1.75 (1.71) Ga); and (5) postorogenic and anorogenic magmatism and metamorphism (<1.75 Ga). [ABSTRACT FROM AUTHOR]

A series of 176 archival cervical intraepithelial neoplasia (CIN) was analysed for the presence, viral load and integration status of 'high-risk' types of human papillomavirus (HR-HPV). The samples were assayed using newly developed methods based on real-time PCR. Two methods for the extraction of DNA from the paraffin-embedded biopsies were compared: a protocol based on the MagNA pure system (Roche) and a Qiagen spin column kit (Qiagen). It was possible to amplify 94% (166) of the samples. Of these, 36, 63 and 80% of the CIN I, II and III cases contained HR-HPV. HPV 16 was the most prevalent, and was found in 20, 28 and 46% of the CIN I, II and III cases, respectively. The second most frequent HR-HPV was type 33 group, and in CIN II it was as prevalent as HPV 16. The median number of copies of HR-HPV per cell was not significantly different in the CIN I, II and III cases, but there was a wide range of viral load values over several magnitudes, regardless of the grade of CIN. All samples were found to contain integrated forms of HPV 16, frequently mixed with an episomal form. [ABSTRACT FROM AUTHOR]

Endometrial regrowth is associated with intense angiogenesis, for which vascular endothelial growth factor-A (VEGF-A) is an important regulator. However, the expression of other members of the VEGF family is less well documented. The aim of this study was to localize members of the VEGF family (VEGF-A, -B and -C), and their receptors (VEGFR1, 2 and 3) in human endometrial blood vessels. Endometrial biopsies collected from four healthy and fertile women were used for immunohistochemistry assessments. Co-localization of VEGF-family proteins with CD34 stained endothelial structures was determined by image analysis. We demonstrate here the marked expression of VEGF-A as well as VEGFR2 and 3 in capillaries. Arterioles expressed VEGF-B, VEGFR1, 2, and 3 moderately and VEGF-A variably. Venules expressed only VEGFR3 markedly. In contrast, VEGF-C was not expressed in the arterioles, but moderately in the capillaries and weakly in the venules. VEGF-B was expressed in all blood vessels; however, VEGF-B was weakly expressed in capillaries and arterioles and moderately expressed in venules and arterioles. Thus, expression of VEGF-A. B and C and VEGF receptors 1-3 in endometrial blood vessels indicates a highly structured involvement of VEGF in the regulation of angiogenesis in the human endometrium. [ABSTRACT FROM AUTHOR]

A method is proposed for determining the optimum sampling frequency in the analog-to-digital analysis of signals in measurement technology. Having this frequency and knowing the characteristics of the input signal, it becomes possible to account for the dynamic characteristics of the analog channel of an analog-to-digital converter and the effect of noise in its sampled output signal. An example is presented to illustrate the calculation of the optimum sampling frequency. [ABSTRACT FROM AUTHOR]

Different methods of measurement of amplitude-modulated signal parameters are proposed and analyzed. The methods are based on scanning the instantaneous signal values with the aid of program-controlled dc voltage levels varying in uniform and nonuniform steps. Block diagrams of modulation meters and their estimated accuracy of amplitude-modulation factor measurements are given. [ABSTRACT FROM AUTHOR]

A method of measuring the parameters of a harmonic signal containing a constant an slowly varying component is proposed and investigated. The method has optimum interference proctection. Expressions are obtained for the algorithms for processing the input signal in analog and digital versions, an estimate of the errors in measuring the parameters is given, and the principle for constructing a digital microprocessor measuring instrument is described. [ABSTRACT FROM AUTHOR]

Rational algorithms for measuring the harmonic coefficient in microprocessor instruments for measuring nonlinear distortions based on digital processing of the codes of the instantaneous values of the signal being investigated are described and the errors of such instruments are obtained. [ABSTRACT FROM AUTHOR]

A method of measuring the parameters of amplitude-modulated signals that is optimum with respect to interference protection and gives a higher measurement accuracy with a shorter measurement time which may be less than the period of the envelope is proposed and investigated. Algorithms for processing the input signal in analog and digital form are obtained, an estimate of the error is given and two versions of a measuring system are proposed. [ABSTRACT FROM AUTHOR]

An interference-protection-optimum method of measuring the frequency of sinusoidal signals using digital filters, based on the root mean square deviation criterion, is investigated. An algorithm for the digital processing of the input signal is proposed, and a model of a digital filter for achieving this and the principle of the construction of a digital measuring instrument for determining the parameters of a sinusoidal signal are proposed. [ABSTRACT FROM AUTHOR]

An optimal polyharmonic measuring signal for the operational monitoring of data transmission and communications systems is proposed, which gives the highest values of the power utilization coefficient, uniformity and accuracy in specifying the amplitudes of the harmonic components, and interference protection. A procedure for synthesizing such signals and a block diagram of the measuring generator are given. [ABSTRACT FROM AUTHOR]

A method of generating precision amplitude-modulated signals based on binary modulation of the length of rectangular pulses of the carrier and subsequent narrow-band filtering of these pulses is proposed. Expressions are obtained for the amplitude-modulation coefficient, and the systematic and instrumental errors are also estimated. [ABSTRACT FROM AUTHOR]

Recurrent algorithms have been derived for calculating the rolling mean and variance, which reduce the memory volume required, improve the speed, and raise the reliability. [ABSTRACT FROM AUTHOR]