A Relationship between the Sizes and Energies of Atomic Orbitals

1975 ◽  
Vol 53 (24) ◽  
pp. 3739-3746 ◽  
Author(s):  
R. Daudel ◽  
P. G. Mezey ◽  
J. D. Goddard ◽  
I. G. Csizmadia
Keyword(s):  
Atomic Orbital ◽  
Closed Shell ◽  
Electronic Energy ◽  
Simple Relationship ◽  
Atomic Orbitals ◽  
Total Electronic Energy ◽  
Simple Quantum ◽  
The Mean ◽  
Simply Connected ◽  
Relationship Of

An approximate relationship of the form[Formula: see text]where [Formula: see text] is the mean potential acting upon and V the mean volume of an electron in a closed shell of an atom has previously been proposed. This concept of a simple relationship between the sizes and energies of atomic orbitals which is predicted by simple quantum mechanical arguments has been further examined in this present work. The potential energy for a series of two electron atoms and ions has been replaced by the total electronic energy as these two quantities are simply connected by the virial theorem. For polyelectronic atoms, a quantity per electron pair which sums to the total electronic energy has been used. The volume of the ith atomic orbital[Formula: see text]has been calculated from its size as previously defined in terms of the spherical quadratic operator evaluated at the orbital centroid of charge. A relationship of the above form between the sizes and energies of atomic orbitals holds well for core orbitals but gradually deteriorates on going from the innermost (core) to outermost (valence) shell.

Ab initio band theory approach to electron energy loss near edge structures

1988 ◽  
Vol 46 ◽  
pp. 506-507
Author(s):  
Xudong Weng ◽  
O.F. Sankey ◽  
Peter Rez
Keyword(s):  
Ab Initio ◽  
Local Density ◽  
Interpolation Method ◽  
Atomic Orbital ◽  
Plane Waves ◽  
Large Set ◽  
Theory Approach ◽  
Band Theory ◽  
Atomic Orbitals ◽  
Pseudopotential Calculations

Single electron band structure techniques have been applied successfully to the interpretation of the near edge structures of metals and other materials. Among various band theories, the linear combination of atomic orbital (LCAO) method is especially simple and interpretable. The commonly used empirical LCAO method is mainly an interpolation method, where the energies and wave functions of atomic orbitals are adjusted in order to fit experimental or more accurately determined electron states. To achieve better accuracy, the size of calculation has to be expanded, for example, to include excited states and more-distant-neighboring atoms. This tends to sacrifice the simplicity and interpretability of the method.In this paper. we adopt an ab initio scheme which incorporates the conceptual advantage of the LCAO method with the accuracy of ab initio pseudopotential calculations. The so called pscudo-atomic-orbitals (PAO's), computed from a free atom within the local-density approximation and the pseudopotential approximation, are used as the basis of expansion, replacing the usually very large set of plane waves in the conventional pseudopotential method. These PAO's however, do not consist of a rigorously complete set of orthonormal states.

Intra-Task Reliability and Specificity of Individual Consistency

1970 ◽  
Vol 30 (2) ◽  
pp. 583-587 ◽  
Author(s):  
Albert V. Carron
Keyword(s):  
Motor Response ◽  
Present Report ◽  
Motor Task ◽  
Response Component ◽  
Linear Movement ◽  
The Mean ◽  
Individual Consistency ◽  
Response Consistency ◽  
Relationship Of ◽  
The Relationship

The present report is based on reanalysis of data of Marisi (1969) in order to examine the relationship of consistency of motor response among the component responses of a single motor task. 120 high school Ss were tested on a special task, the rho. A single trial on this motor task can be logically separated into three component motor responses: reaction time, a short circular movement, and a short linear movement. The results indicated that consistency of motor response was moderately reliable within the response components but tended to be response-component specific. Further, both the reliability and specificity of motor-response consistency were independent of the size of the mean performance scores.

The valence-bond theory of molecular structure II. Reformulation of the theory

1954 ◽  
Vol 223 (1154) ◽  
pp. 306-323 ◽  
Keyword(s):  
Valence Bond ◽  
Closed Shell ◽  
Numerical Illustration ◽  
Atomic Orbitals ◽  
Spin Eigenfunctions ◽  
Spin Pairing ◽  
Vb Structures ◽  
Bond Theory ◽  
Strong Repulsion ◽  
A Charge

The construction of spin eigenfunctions and the evaluation of matrix elements between ,them are discussed generally in preparation for a development of the valence bond (VB) theory along the lines indicated in I. The customary approximation of considering explicitly only the electrons outside a ‘closed shell’ is shown to be defensible. The reformulation of the VB theory is now straightforward, but its final description of bonding is quite new. Atomic orbitals (AO’s) are replaced, whenever they appear, by orthogonalized atomic orbitals (AO’s); but when the assumptions of the conventional theory are rigorously validated in this way the ‘covalent’ structures (now ‘VB’ structures) are found, quite generally, to indicate only strong repulsion between the ‘bonded’ atoms, and formal descriptions of bonding and of bond orders, in terms of ‘spin-pairing’, become nonsensical. Bonding can be described only by admitting into the wave functions polar VB structures; a bond between two atoms demands the appearance (with considerable weight) of pairs of structures differing by a ‘charge hop’ between the atoms concerned. The conventional VB structures are found to be equivalent to certain groupings of VB structures (non-polar and polar) and do, indeed, predict bonds between spin-paired atoms and repulsion between the atoms of different pairs. It is then possible to make full use of chemical intuition, using a plausible combination of conventional structures as a starting approximation in the more rigorous theory. A numerical illustration is provided by a discussion of the Kekulé structures of benzene. Some important characteristics of energy calculations in the VB theory are pointed out. Quantities of intra - and inter -atomic origin are well separated, and the method is apparently well suited to development along either ab initio or empirical lines.

Relationship of Spiritual well-being and emotional intelligence among Iranian' nursing students

2021 ◽  
Vol 15 (6) ◽  
pp. 1634-1640
Author(s):  
Javad Jafari ◽  
Asra Nassehi ◽  
Mohammadali Zareez ◽  
Seydamalek Dadkhah ◽  
Najmeh Saberi ◽  
...  
Keyword(s):  
Emotional Intelligence ◽  
Nursing Students ◽  
Pearson Correlation ◽  
Well Being ◽  
Self Awareness ◽  
Spiritual Well Being ◽  
The Mean ◽  
High Level ◽  
Relationship Of ◽  
Religious Wellbeing

Background: Among all aspects of nursing care, the spiritual one is the issue that has received little attention. Having spiritual wellbeing (SWB) is a necessity to provide appropriate spiritual care. In addition to, the Emotional intelligence (EI) is one of the most important factors in social and professional success and is essential for effective nursing practice. Therefore, aim of study was evaluating the Relationship between SWB and EI among nursing students. Methods: The sample of this descriptive-analytic study consisted of 136 nursing students studying at Bam University of Medical Sciences selected by convenience sampling method. The Bradberry and Greaves 28-item EI scale, Palutzian and Ellison SWB Scale were used to assess the total score of EI and SWB. Collected data were analyzed using descriptive statistics (mean and standard deviation), Pearson correlation coefficient, independent t-test and one-way ANOVA with SPSS v18. Results: The mean score of SWB and EI were 97.1±11.56 and 123.4 + 123.6, respectively. The mean score dimensions of SWB include (religious wellbeing 47.9±6.6, existential wellbeing 49.1±5.7) and dimensions EI: self-awareness, self-management, social awareness, and relationship management were 27.2 3 3.2, 36.2 2 5.4, 25.1 + 3.5 and 35.1 + 4.5, respectively. The majority of students have reported moderate level SWB and high level of emotional intelligence. The factors influencing their level of SWB were academic semester and age (p<0.05). Conclusion: Although the level of students' EI and SWB were at a desirable level in this study, due to the nature of nursing and the interaction between nurses and patients, providing a suitable learning environment for the development of EI is essential. Therefore, it is suggested that nursing policymakers should develop appropriate educational programs for nurses and provide curriculum for students to promote their knowledge and skills. Keywords: spiritual, religious, wellbeing, existential, nursing, emotional intelligence

DNA barcoding and phylogenetic relationship of shrimps (Crustacea: Decapoda) of Bangladesh

2021 ◽  
Vol 7 (1) ◽  
pp. 941-946
Author(s):  
Md Sagir Ahmed ◽  
Sumaiya Salam ◽  
Sayeda Sabrina Sarwar Rumana ◽  
Anindita Barua
Keyword(s):  
Dna Barcoding ◽  
Genetic Divergence ◽  
New Records ◽  
Coi Gene ◽  
Identification System ◽  
Taxonomic Rank ◽  
Macrobrachium Nipponense ◽  
Shrimp Species ◽  
The Mean ◽  
Relationship Of

We adopted DNA barcoding technique using a 658-bp fragment of the mitochondrial cytochrome c oxidase I (COI) gene to identify shrimp species collected from the different areas of Bangladesh. A total of 24 sequences were generated belonging to 14 species including four new records- Macrobrachium nipponense, Macrobrachium kistnense, Exopalaemon carinicauda and Alpheus malleator. Genetic distance measured with Kimura 2 parameter showed that genetic divergence increased with higher taxonomic rank. The mean genetic divergence was evaluated and found to be 0.935%, 22.67% and 30.92% within species, genus and family, respectively. In addition to the barcode-based species identification system, phylogenetic relationships were established where individuals belonging to the same species were grouped under the same clade. Maximum likelihood (ML) was preferred as the statistical method and as expected, the phylogenetic tree complemented and ensured the conventional taxonomy. The present study evidently showed that DNA barcoding can be served as an effective tool to discriminate the shrimp species and this will enhance the understanding on evolution and conservation biology. Bioresearch Commu. 7(1): 941-946, 2021 (January)

Association of Hemoglobin A1C With TDP-43 Pathology in Community-Based Elders

Neurology ◽  
2021 ◽  
pp. 10.1212/WNL.0000000000012025
Author(s):  
Shahram Oveisgharan ◽  
Ana W. Capuano ◽  
Sukriti Nag ◽  
Sonal Agrawal ◽  
Lisa L. Barnes ◽  
...  
Keyword(s):  
Severity Score ◽  
Hemoglobin A1c ◽  
Oldest Old ◽  
Brain Regions ◽  
Inverse Association ◽  
Community Based ◽  
Cytoplasmic Inclusions ◽  
The Mean ◽  
High Level ◽  
Relationship Of

Objective.We tested the hypothesis that an inverse association exists between diabetes mellitus (DM) and hemoglobin A1C (A1C) with Transactive response DNA binding protein 43 (TDP-43) levels in older adults.Methods.We leveraged antemortem and postmortem data of decedents from three community-based clinical-pathological studies. DM status, A1C levels, and medications for DM were documented annually. TDP-43 cytoplasmic inclusions, evaluated in 6 brain regions using immunohistochemistry, were used to obtain a semiquantitative TDP-43 score (0-5) in each region, and scores were averaged across regions to obtain a TDP-43 severity score. We used linear regressions to test the association of DM and A1C with the TDP-43 severity score.Results.On average, participants (n=817) were 90 years old at the time of death, three fourth were women, and one fourth had DM. The mean A1C was 6.0% (SD=0.6). TDP-43 was observed in 54% of participants, and the mean TDP-43 score was 0.7 (range 0-4.5). A higher level of A1C was associated with a lower TDP-43 score (estimate=-0.156, S.E.=0.060, p=0.009) while DM had a borderline inverse association with the TDP-43 score (estimate=-0.163, S.E.=0.087, p=0.060). The association of higher levels of A1C with lower TDP-43 scores persisted after further adjustment by Apolipoprotein ε4, vascular risk factors, stroke, and hypoglycemic medications. Exclusion of the oldest old participants did not change the results.Conclusion.Overall, the results suggest that a high level of A1C is associated with less TDP-43 proteinopathy in older persons while the relationship of DM with TDP-43 needs further study.

Respiratory Periodicity and Electroencephalogram Arousals During Sleep in Older Adults

2007 ◽  
Vol 8 (4) ◽  
pp. 249-260 ◽  
Author(s):  
Barbara Waag Carlson ◽  
Virginia J. Neelon ◽  
John R. Carlson ◽  
Marilyn Hartman ◽  
Sunil Dogra
Keyword(s):  
Older Adults ◽  
Exploratory Study ◽  
High Variability ◽  
Arterial Oxygenation ◽  
Type B ◽  
Breathing Patterns ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship ◽  
Electroencephalogram Eeg

The aim of this exploratory study was to examine the relationship of electroencephalogram (EEG) arousals to breathing patterns and the relationship of both arousals and breathing patterns to arterial oxygenation during sleep in older adults. Five older adults were monitored using standard polysomnography. Records were divided into 5-min segments and breathing patterns identified based on the level of respiratory periodicity and the variability in the frequency of breathing cycles. Standard criteria were used to determine sleep states and occurrence of EEG arousals. High respiratory periodicity was seen in 23% of the segments, whereas 24% had low respiratory periodicity with minimal variability in the frequency of breathing (Type A low respiratory periodicity) and 53% had low respiratory periodicity with high variability in the frequency of breathing (Type B low respiratory periodicity). Nearly all (97%) segments with high respiratory periodicity had EEG arousals, whereas fewer segments (33%) with low respiratory periodicity had arousals, regardless of the stage of sleep. Desaturations occurred more often in segments with high respiratory periodicity, F (2,4) = 57.3, p < .001, but overall, the mean SaO2 of segments with high respiratory periodicity did not differ from levels seen in segments with low respiratory periodicity, F( 2,4) = 0.77, ns. Our findings suggest that high respiratory periodicity is a common feature of EEG arousals and, in older adults, may be important for maintaining oxygen levels during desaturations during sleep.

scholarly journals Relationship of altitude mountain sickness and smoking: a Catalan traveller’s cohort study

BMJ Open ◽  
2017 ◽  
Vol 7 (9) ◽  
pp. e017058 ◽  
Author(s):  
Alba Sánchez-Mascuñano ◽  
Cristina Masuet-Aumatell ◽  
Sergio Morchón-Ramos ◽  
Josep M Ramon
Keyword(s):  
Smoking Status ◽  
Medical Advice ◽  
Health Clinic ◽  
Travel Health ◽  
Systemic Corticosteroids ◽  
The Mean ◽  
Mountain Sickness ◽  
Relationship Of ◽  
The Relationship ◽  
Chronic Use

ObjectivesThe aim of this study is to analyse the relationship between smoking andaltitude mountain sicknessin a cohort of travellers to 2500 metres above sea level (masl) or higher.SettingTravel Health Clinic at the Hospital Universitari de Bellvitge, in Barcelona, Spain.ParticipantsA total of 302 adults seeking medical advice at the travel clinic, between July 2012 and August 2014, before travelling to 2500 masl or above, who agreed to participate in the study and to be contacted after the trip were included. Individuals who met the following criteria were excluded: younger than 18 years old, taking carbonic anhydrase inhibitors for chronic use, undergoing treatment with systemic corticosteroids and taking any medication that might prevent or treat altitude mountain sickness (AMS) prior to or during the trip. The majority of participants were women (n=156, 51.7%). The mean age was 37.7 years (SD 12.3). The studied cohort included 74 smokers (24.5%), 158 (52.3%) non-smokers and 70 (23.2%) ex-smokers. No statistical differences were observed between different sociodemographic characteristics, constitutional symptoms or drug use and smoking status.OutcomesThe main outcome was the development of AMS, which was defined according to the Lake Louise AMS criteria.ResultsAMS, according to the Lake Louise score, was significantly lower in smokers; the value was 14.9%, 95% CI (6.8 to 23.0%) in smokers and 29.4%, 95% CI (23.5 to 35.3%) in non-smokers with an adjusted OR of 0.54, 95% CI (0.31 to 0.97) independent of gender, age and maximum altitude reached.ConclusionsThese results suggest that smoking could reduce the risk of AMS in non-acclimated individuals. Further studies should be performed in larger cohorts of travellers to confirm these results. Despite the results, smoking must be strongly discouraged because it greatly increases the risk of cardiorespiratory diseases, cancer and other diseases.

scholarly journals Frequency of non-motor symptoms in Peruvian patients with Parkinson's disease

2013 ◽  
Vol 71 (4) ◽  
pp. 216-219 ◽  
Author(s):  
Carlos Cosentino ◽  
Yesenia Nuñez ◽  
Luis Torres
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Progressive Increase ◽  
Motor Symptoms ◽  
Number Of Patients ◽  
Progression Of Disease ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship ◽  
Non Motor Symptoms

Introduction: Non-motor symptoms in Parkinson's disease are often not well recognized in clinical practice. Non-motor symptoms questionnaire (NMSQuest) is a simple instrument that allows patients or caregivers to report non-motor symptoms in a practical manner. Objective: We attempted to determine the prevalence of non-motor symptoms in three hundred Parkinson's disease outpatients. Results: The mean total non-motor symptoms was 12.41, ranging from 0 to 27 of a maximum of 30. At least one was present in 99.3% of patients. A progressive increase in mean total score was observed across each 5-year interval. Depression domain scored the most “positive” answers while urinary and anxiety /memory were secondly and thirdly most prevalent respectively. Conclusion: The large number of patients included in this study allowed evaluation of the occurrence of non-motor symptoms in early and advanced disease in addition to the relationship of these kinds of symptoms with progression of disease.

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