scholarly journals P-WAVE MESON SPECTRUM IN A RELATIVISTIC MODEL WITH INSTANTON INDUCED INTERACTION

2009 ◽  
Vol 24 (22) ◽  
pp. 4209-4220 ◽  
Author(s):  
K. B. VIJAYA KUMAR ◽  
BHAVYASHRI ◽  
YONG-LIANG MA ◽  
ANTONY PRAKASH MONTEIRO
Keyword(s):  
P Wave ◽  
Exchange Potential ◽  
Meson Spectrum ◽  
Relativistic Model ◽  
Confinement Potential ◽  
Lorentz Scalar ◽  
The Masses ◽  
Good Agreement

On the basis of the phenomenological relativistic harmonic models for quarks, we have obtained the masses of P-wave mesons. The full Hamiltonian used in the investigation has Lorentz scalar + vector confinement potential, along with one-gluon-exchange potential (OGEP) and the instanton-induced quark–antiquark interaction (III). A good agreement is obtained with the experimental masses. The respective role of III and OGEP for the determination of the meson masses is discussed.

C-V and DLTS Investigations of GaAs/InGaAs/GaAs Strained Quantum Well Structures

1993 ◽  
Vol 300 ◽  
Author(s):  
S. Subramanian ◽  
B. M. Arora ◽  
A. K. Srivastava ◽  
S. Banerjee ◽  
G. Fernandes
Keyword(s):  
Quantum Well ◽  
Band Offset ◽  
Full Width ◽  
Single Quantum ◽  
Single Quantum Well ◽  
Quantum Well Structures ◽  
Strained Quantum Well ◽  
Good Agreement

ABSTRACTIn this paper we report a modified Kroemer's analysis for the determination of the band offset (ΔEc) of single quantum well (SQW) structures from simple C-V measurements. The experimental carrier profile from an MOVPE grown pseudomorphic GaAs/InGaAs/GaAs strained SQW structure shows a sharp accumulation peak bounded by depletion regions on either side. The full width at half maximum of the accumulation peak is comparable to the width of the quantum well. The value of ΔEC obtained from C-V measurement is in good agreement with the values determined by simulation and photoluminescence measurements. DLTS measurements on our SQW samples do not show any peaks which is contrary to the published reports. We believe that it is necessary to carefully isolate the role of interface states, before assigning a DLTS peak to emission from the quantum well.

scholarly journals Cepheid Variables: Period and Mass Determination

1995 ◽  
Vol 10 ◽  
pp. 594-596
Author(s):  
Pawel Moskalik
Keyword(s):  
Light Curve ◽  
Vibrational Modes ◽  
Mass Determination ◽  
The Galaxy ◽  
Cepheid Variables ◽  
Mass Calibration ◽  
The Masses ◽  
Standing Problem ◽  
Good Agreement

Determination of masses has been a long standing problem in the Cepheid research. Since the early days of Cepheid modeling different methods of mass calibration have lead to conflicting results, implying serious discrepancies between the evolution and pulsation theories (see Cox 1980 for a review). In recent years this situtation has been mostly remedied, and the Baade-Wesselink masses, pulsation masses and evolutionary masses are now in good agreement with each other (e.g., Gieren 1989). However, both the bump masses inferred from the position of the secondary bump on the light curve and the beat masses obtained from the period ratios of the double mode Cepheids turned out to be very resilient to a reconciliation.There are 13 Cepheids in the Galaxy in which two vibrational modes are simultaneously excited (e.g., Szabados 1988). The period ratios measured in these variables can be used in conjunction with the linear pulsation theory to infer the masses of these stars. The method was first applied by Petersen (1973) who obtained masses ranging from 1Mʘ to 3Mʘ for Cepheids with fundamental mode periods between 2.1 d and 6.3 d. Such ‘beat” masses are 2—4 times smaller than the evolutionary or Baade-Wesselink masses for these objects.

scholarly journals The role of SWOT analysis in evaluating performance and developing the strategic plan for the non-profit sector: دور تحليل سوات SWOT في تقييم الأداء وتطوير الخطة الاستراتيجية للقطاع غير الربحي

2021 ◽  
Vol 5 (18) ◽  
pp. 160-134
Author(s):  
Atef Mohammad Abd El-Bari Mabrouk, Mohammad Al-Mahdi Mustafa Atef Mohammad Abd El-Bari Mabrouk, Mohammad Al-Mahdi Mustafa
Keyword(s):  
Strategic Planning ◽  
Environmental Analysis ◽  
Swot Analysis ◽  
Main Hypothesis ◽  
Non Profit ◽  
And Performance ◽  
The Masses ◽  
Assessment Requirements

  The study aimed to shed light on the concepts of internal and external environmental analysis among Non-profit associations in Riyadh and determination of impact of environmental analysis variables on performance assessment requirements, and the strategic planning mechanism in these associations accordingly. The importance of the study stems from supporting officials in the practice of strategic planning, which helps organizations achieve their goals, and the application to a non-profit sector is characterized by being more sensitive to the needs of the masses and societies, in addition to what the study adds to the Arab library interested in strategic planning. The formulation of the main hypothesis was “There is a significant relationship between the environmental analysis variables and the performance evaluation requirements of Non-profit associations”. The questionnaire was developed to collect data, and the number of responses reached 391 employees of the applied societies. The most important results of the study include, among other things: The variables value of internal and external environmental analysis, and that of the variables of effectiveness, efficiency, suitability and performance continuity are both above medium; There is a significant impact of the variables of internal and external environmental analysis on both the effectiveness of the performance, and the adequacy of the performance for beneficiary's objectives; There is a significant effect of the external environmental analysis variables on the efficiency of performance and on the continuity of the performance of the associations, while there is no significant effect of the variables of internal environmental analysis.

Helicobacter pylori infection and neopterin

Pteridines ◽  
2001 ◽  
Vol 12 (3) ◽  
pp. 126-129 ◽  
Author(s):  
Maximilian Ledochowski ◽  
Christian Murr ◽  
Cornelia Lass-Flörl ◽  
Dietmar Fuchs
Keyword(s):  
Helicobacter Pylori ◽  
Great Majority ◽  
Antibody Testing ◽  
Serum Neopterin ◽  
H Pylori ◽  
Cellular Immune ◽  
Specific Health ◽  
Good Agreement

In order to find out whether chronic immune stimulation is associated with Helicobacter pylori infection we studied 425 healthy individuals (aged 57.6 ± 9.22 years, s.d.) who were performing a health check up without having any specific health problems. Blood was drawn for Hpylori antibody testing, determination of routine laboratory parameters, differential blood count and measuring neopterin concentrations. In addition, in individuals seropositive for H pylori, measurement of 13C02 exhalation after administration of 75 mg 13C-Urea was performed to test for the presence of these microorganisms in the gut. One hundred and ninety subjects were H pylori seropositive (antibody titer> 4) and they had higher serum neopterin concentrations (serum neopterin: 6.38 nM ± 3.3 S.D.) compared to seronegative subjects (serum neopterin: 5.74 ± 2.7 nM, p =0.027, Student's ttest). Among the H pylori seropositive individuals no such difference existed between breath test positive (serum neopterin: 6.1 ± 3.1 nM) and negative ones (serum neopterin: 6.1 ± 2.0 nM; p = n. s.). Increased production of neopterin is indicative for an activated cellular immune response. Antibody seropositive patients present with higher neopterin levels than seronegatives even when H pylori seemed to be no longer present in the gut. Surprisingly neopterin concentrations were not related to the presence/absence of bacteria in the gut. Higher neopterin concentrations in H pylori seropositive individuals would be in good agreement with the view of H pylori infection as a risk factor for developing atherosclerosis, since in earlier studies carotid stenosis was found to be associated with higher neopterin concentrations. In that study as in ours, the great majority of neopterin concentrations found were well within the normal range of healthy controls. Our data point to a role of H. pylori to induce a long-lasting albeit moderate deterioration of the cellular immune system, which may contribute to increase the risk of atherosclerosis.

Mechanisms of the HF/H2O Vapor Phase Etching of SiO2

1992 ◽  
Vol 35 (3) ◽  
pp. 21-26
Author(s):  
C. Helms ◽  
B. Deal
Keyword(s):  
Vapor Phase ◽  
Etch Rate ◽  
Pressure Data ◽  
Detailed Model ◽  
Wafer Temperature ◽  
Partial Pressures ◽  
Aqueous Etching ◽  
Good Agreement

In this paper we report on studies of the mechanisms responsible for HF/H2O etching and cleaning of Si surfaces. From these studies we have clearly established that the role of water is to provide a condensed solvent medium for the HF on the surface. Our results, as well as those in the literature, show that if the partial pressures of HF and H2O are too low (or sample temperature too high), condensation does not occur and little or no etching is observed. Based on these ideas, and pressure data from the literature, we have developed a detailed model that provides for the calculation of the onset of condensation as a function of wafer temperature and reactant partial pressures. In addition, the model allows determination of the HF concentration in the condensed H2O film. Comparison of etch rates obtained for aqueous etching as a function of HF concentration, and vapor phase etching as a function of calculated HF concentration, show good agreement. The vapor phase etch rate data, as a function of wafer temperature, total HF + H2O pressure, and partial pressure ratios, will be presented in detail along with information on the model.

A Molecular Approach to Immunoscintigraphy: A Study of the T-Antigen Conformation on the Surface of Tumors

1987 ◽  
Vol 26 (01) ◽  
pp. 1-6 ◽  
Author(s):  
S. Selvaraj ◽  
M. R. Suresh ◽  
G. McLean ◽  
D. Willans ◽  
C. Turner ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Tumor Cell ◽  
T Antigen ◽  
Human Carcinomas ◽  
Animal Tumor ◽  
Synthetic Antigens

The role of glycoconjugates in tumor cell differentiation has been well documented. We have examined the expression of the two anomers of the Thomsen-Friedenreich antigen on the surface of human, canine and murine tumor cell membranes both in vitro and in vivo. This has been accomplished through the synthesis of the disaccharide terminal residues in both a and ß configuration. Both entities were used to generate murine monoclonal antibodies which recognized the carbohydrate determinants. The determination of fine specificities of these antibodies was effected by means of cellular uptake, immunohistopathology and immunoscintigraphy. Examination of pathological specimens of human and canine tumor tissue indicated that the expressed antigen was in the β configuration. More than 89% of all human carcinomas tested expressed the antigen in the above anomeric form. The combination of synthetic antigens and monoclonal antibodies raised specifically against them provide us with invaluable tools for the study of tumor marker expression in humans and their respective animal tumor models.

On The Mechanism Of Heparin-Induced Potentiation Of Platelet Aggregation

1981 ◽  
Author(s):  
M Yamamoto ◽  
K Watanabe ◽  
Y Ando ◽  
H Iri ◽  
N Fujiyama ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Platelet Activation ◽  
Coagulation Factors ◽  
Marked Enhancement ◽  
Matrix Bound ◽  
Induced Aggregation ◽  
Aggregation Of Platelets ◽  
Plasma Heparin

It has been suggested that heparin caused potentiation of aggregation induced by ADP or epinephrine. The exact mechanism of heparin-induced platelet activation, however, remained unknown. In this paper, we have investigated the role of anti-thrombin III ( AT ) in heparin-induced platelet activation using purified AT and AT depleted plasma. When ADP or epinephrine was added to citrated PRP one minute after addition of heparin ( 1 u/ml, porcine intestinal mucosal heparin, Sigma Co. USA ), marked enhancement of platelet aggregation was observed, compared with the degree of aggregation in the absence of heparin. However, in platelet suspensions prepared in modified Tyrode’s solution, heparin exhibited no potentiating effect on platelet aggregation induced by epinephrine or ADP. Potentiation of epinephrine- or ADP-induced platelet aggregation by heparin was demonstrated when purified AT was added to platelet suspensions at a concentration of 20 μg/ml. AT depleted plasma, which was prepared by immunosorption using matrix-bound antibodies to AT, retained no AT, while determination of α1-antitrypsinα2- macroglobulin and fibrinogen in AT depleted plasma produced values which corresponded to those of the original plasma when dilution factor was taken into account. The activities of coagulation factors were also comparable to those of the original plasma. Heparin exhibited potentiating effect on ADP- or epinephrine-induced aggregation of platelets in original plasma, but no effect in AT depleted plasma. When purified AT was added back to AT depleted plasma at a concentration of 20 μg/ml, potentiation of platelet aggregation by heparin was clearly demonstrated.Our results suggest that effect of heparin on platelet aggregation is also mediated by anti-thrombin III.

COMPARATIVE ACTION OF VARIOUS OESTROGENIC COMPOUNDS ON MOUSE VAGINAL SIALIC ACIDS (II)

1969 ◽  
Vol 62 (4) ◽  
pp. 663-670 ◽  
Author(s):  
Lars Carlborg
Keyword(s):  
Sialic Acid ◽  
Response Curve ◽  
Sialic Acids ◽  
Clear Cut ◽  
Suitable Parameter ◽  
Sufficient Degree ◽  
Comparative Action ◽  
Relative Potencies ◽  
Good Agreement

ABSTRACT Oestrogens administered in lower doses than necessary to induce full cornification of the mouse vagina induce mucification. It was shown previously that the degree of mucification could be estimated by quantitative determination of sialic acids. A suitable parameter for oestrogen assay was the measurement of vaginal sialic acid concentration which exhibited a clear cut dose response curve. Eleven assays of various oestrogens were performed with this method. Their estimated relative potencies were in good agreement with other routine oestrogen assays. A statistically sufficient degree of precision was found. The sensitivity was of the same order, or slightly higher, than the Allen-Doisy test.

ІНТЕРПРЕТАЦІЯ КАТЕГОРІЇ РОЗВИТКУ В СУЧАСНІЙ ПСИХОЛОГІЇ

1970 ◽  
Vol 8 (1) ◽  
pp. 22-30
Author(s):  
Анжеліка Шамне
Keyword(s):  
Cultural Context ◽  
Developmental Psychology ◽  
Structure And Dynamics ◽  
Modern Psychology ◽  
Development Site ◽  
Approaches To Study ◽  
Methodological Approaches ◽  
Self Motion

У статті розглянуто сучасні підходи до інтерпретації категорії розвитку, розкрито теоретичні  та методологічні підходи до вивчення категорії розвитку у сучасній психології, визначено її психологічний  зміст,   моделі,   структуру   та   динаміку.   Категорія   розвитку   розглядається   як   епіцентр   наукової  проблематики у психології та як поняття інтегративного типу. Розвиток проаналізовано як категорію,  явище і проблему психології розвитку в різних аспектах аналізу. Розглянуто місце розвитку в системі  споріднених психологічних понять. У статті також аналізуються психологічні аспекти теоретичних та  методологічних  постнекласичних  тенденцій  вивчення  природи,  характеру  та  визначення  психічного  розвитку. Постнекласична парадигма та плюралістична методологія пізнання визначають розмитість  дисциплінарної мови  та  врахування  ролі  соціокультурного  контексту  при  вивченні  психологічних явищ.  Важливими тенденціями сучасного теоретико-методологічного стану психологічних досліджень розвитку  також є визнання неефективності моністичного підходу до його вивчення, взаємозв'язок теоретичних ідей  та   спроби   створення   метатеоретичних   схем,   постнекласичне   розуміння   розвитку   як   принципово  незавершеного   процесу   саморуху,   актуалізація   антропологічного   діапазону   проблем   та   посилення  спрямованості на роль культурного контексту в дослідженні розвитку людини.  The article deals with the modern approaches to the interpretation of the category of development, reveals  the theoretical and methodological approaches to study of development in modern psychology, its psychological  content, patterns, structure and dynamics. Category of development is viewed as an epicenter of scientific issues in  modern  psychology  and  the  concept  of  the  integrative  type.  Category  of  development  is  considered  as  the  phenomenon  and  the  problem  of  developmental  psychology  in  various  aspects  of  the  analysis.  Analyzed  the  development site in the related psychological concepts. The article analyzes the psychological aspects of theoretical  and methodological postnonclassical contemporary trends in the study of nature, character, and determination of  mental  development.  Postnonclassical  paradigm  and  pluralistic  methodology  of  knowledge  determine  the  disciplinary blurring and increase of the role of the analysis of socio-cultural context in the study of psychological  phenomenon. The important tendencies of modern theoretical and methodological state of psychological researches  of development are facts of inefficiency of the monistic approach to its study, interconnection of theoretical ideas  and   attempts   of  creating   metatheoretical   schemes,   postnonclassical   understanding   of   development   as   a  fundamentally  uncompleted  process  of  self-motion,  actualization  of  anthropological  range  of  problems  and  strengthening of focus on the role of cultural context in research of human development.   

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