bluuebunny/crossref_metadata_2025_split huggingface dataset:
Length-Weight Relationship and the Distribution of Intestinal Helminth Parasites in Freshwater Fishes from Amansea and Ebenebe Rivers in Anambra State, Nigeria
Authors: Obiageli A. Okeke , W. Obinna Obinabo , Imakwu C. A. , C. Janefrances Okeke , N. Chinwendu Okafor , Nwadike C. C. , O. Nnatuanya I. , I. Afoemezie P. 
Published: August 2022

Aims: The current study was carried out to evaluate the prevalence and distribution of intestinal helminths in freshwater fishes.
Study Design: The study was a survey done to establish the type of intestinal parasite found in freshwater fish in the rivers.
Place and Duration of Study: The fish samples were collected from Amansea and Ebenebe Rivers from November 2021 to January 2022.
Methodology: Intestinal parasites of three (3) fish species commonly found in these rivers (Parachanna obscura, Clarias gariepinus, and Ctenopoma kingsleyae) were examined. A comparative evaluation of the prevalence and distribution of the parasite was done in relation to their gender, location, weight, and length.
Results: A total of 24 fish samples were collected in the Amansea River and 26 samples were collected in Ebenebe River. Seventeen (17) samples of P. obscura, 21 samples of C. gariepinus and 12 samples of C. kingsleyae caught with the cast nets of various mesh sizes and gill traps by artisanal fishermen in Rivers were bought early in the morning, transported to the Laboratory and identified based on morphological features. Out of a total of 50 fish sampled, 17 fishes (34% of the total sample) were infected by intestinal helminths. P. obscura had the highest parasite prevalence (47.06%) followed by C. gariepinus (42.86%). However, no parasite was recorded in C. kingsleyae. Prevalence of intestinal parasites in Ebenebe (18.00%) was higher than in Amansea (16.00) with a significant difference in prevalence (p<0.05), while parasite abundance was higher in Amansea (50.94%) than in Ebenebe (49.06%) with significant difference (p<0.05). Females had the highest prevalence (35.00%) against male fishes (33.33%) with no significant difference. A total number of 53 parasites belonging to 7 genera were recovered in this study. Parasites identified were nematodes: Procamallanus sp. (41.5%), Camallanus sp. (9.43%), Rhabdochona sp. (26.42%), Contracaecum sp. (7.55%), and Spinitectus sp. (5.66%); cestodes: Polyonchobothrium sp. (5.66%); and trematodes: Clinostomum sp (3.77%). The highest parasite abundance was recorded in Procamallanus sp. (41.5%), while Clinostomum sp had the least (3.77%).
Conclusion: This study revealed that the prevalence of intestinal parasites in freshwater fish is relatively high. Therefore, fish consumers should subject the fish to proper processing before consumption as some of these parasites are of zoonotic importance.
Temporal sensitivity deficits in patients with high‐risk drusen
Authors: Phipps J A , Guymer R H , Vingrys A J 
Published: July 2002

Purpose: Data is reported from an ongoing trial considering functional losses in patients with high‐risk drusen. We evaluate the temporal processing in 12 subjects: four patients with high‐risk drusen, four age‐matched controls and four young observers aged 22–30. Methods: Subjects were tested using frequency‐doubling technology, macula static and flicker fields on a Medmont perimeter and foveal temporal contrast sensitivity at 2, 5, 10 and 24 Hz. Results: Eyes with high‐risk drusen had good visual acuity (6/9.5–2 or better). All control eyes had normal fields for static, flicker and frequency‐doubling perimetry. All high‐risk drusen eyes had normal static perimetry in the presence of abnormal flicker and frequency‐doubling perimetry. High‐risk drusen eyes showed a generalized loss of temporal sensitivity across all frequencies. Conclusions: We conclude that eyes with high‐risk drusen show losses to temporal stimuli in the presence of near‐normal acuity and static thresholds. We suggest that flickering stimuli might be useful for detecting and monitoring such patients.
Theory of phonon inelastic atom–surface scattering. II. Approximate methods and applications to resonance and adsorption
Authors: Choi B. H. , Poe R. T. 
Published: July 2002

Approximate theoretical schemes for the calculation of the phonon inelastic scattering were derived from the formulation in the preceding paper. They can be adopted to flexible input potentials and are more realistic compared to the schemes that have been employed so far and at the same time are capable of yielding effective ab initio computation. An iterative coupled integral equation method thus obtained is much more tractable than that of the coupled differential equation when the phonons are taken into account. In this approach, the multiphonon transitions are readily obtained as higher order processes with the potential matrix elements being limited to the dominant one-phonon transitions. The S matrix elements of both elastic reflection and simultaneous diffraction and phonon transitions can also be obtained from the coupled channel transition matrix (CCTM) approach derived from the diffractive wave Green function where the coupling between the reciprocal
lattice points due to the atom–surface interaction are taken into consideration. A unitarization method of CCTM S matrix was also discussed. Employing the diffractive standing wave Green function, we derived the coupled channel reactance matrix (CCRM) method. Some advantages of this scheme over CCTM are that the scattering wave functions needed for the calculation are all real, and the unitarized S matrix can be directly obtained within a truncated basis set. As an application of the present scattering formulation, the bound state resonance scattering method of the atom–surface system was presented within the framework of Feshbach internal excitation approach. Our emphasis here is the role of the phonon transitions in the selective adsorption and desorption. Our method is adoptable again to arbitrary and flexible input potentials and yields ab initio calculational procedures from which the resonance energies, the energy shift and width functions, the line shapes, and the intensities of the simultaneous diffraction and phonon transitions can be obtained. Among other effective calculational schemes, we discussed a method where the bound state resonance scattering amplitude is computed from simplified wave functions which are obtained as products of the spatial wave function generated from the elastic diffraction potential and that of the phonon state. The nonresonant potential scattering amplitude in the method is obtained from CCTM approach within the open channels. Finally, a method of obtaining the quantal adsorption rates and sticking probabilities, which deals with the half-collision processes, was presented as another application of our scattering formulation.
Nonequilibrium electronic polarization of the solvent in photoionization
Authors: Delahay Paul , Dziedzic Andrew 
Published: July 2002

The energetics of photoionization in condensed phases includes a significant contribution from nonequilibrium processes arising from dielectric dispersion of the solvent at the prevailing photon energy. The solvent is polarized by the varying electric field caused by the change of ionic valence as a result of photoionization. This ionic field varies in a time interval determined by the frequency of incident radiation. The following contributions from nonequilibrium processes to the energetics of photoionization are calculated for transparent and absorbing solvents: electronic polarization, London dispersion, and Born repulsion energies for a discrete model of coordinated solvent molecules in the inner-sphere solvation shell of anions and cations; electronic polarization of the outer-sphere region for a continuous medium model. The losses resulting from the rapid variation of the ionic field for an absorbing solvent are calculated for the inner- and outer-sphere regions, respectively, from a discrete model and a continuous medium. Damping of the ionic field resulting from solvent absorption is negligible. The theory is applied to aqueous solutions in the 7–10.4 eV range of photon energies by using dielectric data from reflectance spectroscopy of liquid water. Experimental dispersion spectra for photoelectron emission have the shape predicted by theory and display all the extrema at the photon energies of the calculated curves. The very pronounced effect of ionic strength on the balance between inner- and outer-sphere contributions predicted by theory (inner–outer sphere splitting) is fully confirmed by experiment. Dispersion spectra of inorganic ions in the range of each of the two absorption bands of liquid water (maxima at ∼8.2 and 10.0 eV) therefore exhibit a double maximum for normal dispersion and a double minimum for anomalous dispersion (12 extrema between 7.2 and 10.4 eV). Specific effect of the nature of anions is evident above 9.0 eV in inner–outer sphere
splitting. The present study provides a way of probing the response of liquids and solutions to the rapidly varying intense ionic field resulting from the process of photoionization.
Stimulated Raman amplification spectra in a four-level atomic system interacting with a strong bichromatic field
Authors: Mavroyannis Constantine 
Published: July 2002

We have considered the stimulated Raman spectra arising from interaction of a four-level atom with a strong bichromatic field and a weak signal field simultaneously. The atomic system consists of two upper excited states ‖3〉 and ‖4〉 and two lower states ‖1〉 and ‖2〉, where the metastable state ‖2〉 is depleted through the action of two strong laser fields operating between the states ‖2〉↔‖4〉 and ‖2〉↔‖3〉, respectively. Using a model Hamiltonian, where all the free and interacting fields are quantized, and the Green function method in the limit of high photon densities of both laser fields, we have studied stimulated two-photon processes near the frequencies ±ω≊ω21≊ω41 −ωa≊ω31 −ωb for the ‖1〉→‖2〉 electric dipole forbidden transition describing physical processes, where one photon of the signal field with frequency ω41(ω31) is absorbed while a photon of the laser field with frequency ωa(ωb) is emitted and vice versa; ωij refers to an atomic transition frequency between the states ‖i〉 and ‖j〉. The spectral function for the stimulated two-photon processes consists of a central peak at the frequency ω=ω21, which has a delta function distribution indicating the stability of the mode in question, and three pairs of sidebands, where one pair of sidebands is induced by each laser field, respectively, while the third pair of sidebands is induced by both laser fields simultaneously. The intensities of the sidebands are always negative indicating that strong amplification (stimulated emission) takes place at the corresponding frequencies. The computed resonance and off-resonance spectra are graphically presented and discussed. When a classical description for both laser fields is used, the spectral function is found to describe one pair of sidebands, which is induced by both laser fields simultaneously; this classical result is graphically presented and compared with those obtained when the fields are quantized. It is shown that the results obtained when the fields are quantized and in the limit of high photon densities describe the classical
as well as the quantum nature of the photon fields which is lost in the classical picture. The effect of the quantum nature or, equivalently, the boson character of the photon is to split the ‘‘classical’’ spectrum described by one pair of sidebands into three pairs, whose sum of relative intensities is equal to that of the original pair derived classically.
A theoretical evaluation of the vinyl torsional potential in protoporphyrins
Authors: Findsen Leonore A. , Bocian David F. , Birge Robert R. 
Published: July 2002

The potential surfaces for the vinyl torsion in 2,4-divinyl porphyrins are calculated by using semiempirical [INDO (intermediate neglect of differential overlap) and INDO-PSDCI (partial single and double excitation configuration interaction)] molecular orbital theory. Calculations are carried out on the two pyrrole hydrogen tautomers of the free base porphyrin as well as on the porphyrin dianion. The calculated potential surfaces are predicted to have energy maxima at 0° and 180° due to steric hindrance. A third maximum near 70° (approximately perpendicular) is predicted due to electronic destabilization associated with the loss of conjugation and a decrease in dispersive stabilization energy. The torsional surface associated with the porphyrin dianion is qualitatively different from that calculated for the free base porphyrin due primarily to more effective conjugation of the vinyl group into the porphyrin macrocycle in the dianion. Neither pyrrole hydrogen tautomerization nor internal rotation of the second vinyl group have any significant effect on the torsional potential surface of the first vinyl group. The latter result indicates that the vinyl groups are effectively ‘‘uncoupled’’ in 2,4-divinyl porphyrins. A complete vibronic analysis is carried out by calculating the torsional energy levels using a free internal rotor basis set containing 201 basis functions. A Boltzmann analysis of level occupation and numerical evaluation of the individual torsional expectation values are used in conjunction to calculate average dihedral angles as a function of temperature. We predict that the average torsional angle of the vinyl group is 114.2° in the free base porphyrin and 121.2° in the porphyrin dianion at ambient temperature. In order to compare these results with NMR studies, we also calculate the average angle by evaluating the expectation value of sin2 Φ. This expectation function, when transformed into an angular measurement (〈Φ*〉=sin−1〈sin2 Φ〉), restricts angular expectation values to lie within the first quadrant. Calculations of 〈Φ*〉 yield average angles of 46.3° for the free base porphyrin and 47.5° for the porphyrin dianion. These values are in good agreement with the NMR experimental
value of 51° which is based on a 〈sin2 Φ〉 measurement. The origins of the nonplanarity of the vinyl substituents are analyzed in terms of repulsive, dispersive, and electrostatic nonbonding interactions as well as bonding and electron correlation effects. We demonstrate that many of the predictive limitations associated with the use of INDO semiempirical procedures to calculate potential surfaces are improved by the inclusion of electron correlation embodied in double excitation configuration interaction.
Two-photon excitation of dense sodium vapor near the n
d 2D5/2, 3/2 (n=3, 4, 5) levels: Na2 1 3Σ+g→1 3Σ+u excimer emission
Authors: Bajic S. J. , Compton R. N. , Stockdale J. A. D. , Konowalow Daniel D. 
Published: July 2002

Laser excitation and ionization processes in dense (1–10 Torr) sodium vapor have been studied for laser wavelengths near the two-photon allowed nd 2D(n=3, 4, 5) and ns 2S(n=4, 5, 6) states. In particular, the 1 3Σ+g→1 3Σ+u excimer emission in Na2, predicted in 1980 by Konowalow and Julienne and observed recently by Dinev et al, was studied here in greater detail. Strong excimer emission (∼830 nm) was observed for two-photon pumping to both sides of the unresolved 4D states, and weak excimer emission was seen when pumping near the 5D levels. The excimer emission exhibits a complicated pump laser profile with a pronounced ‘‘dip’’ at the 4d 2D two-photon resonance. Similarly, [2+1] photon ionization via the 3d 2D and 4d 2D states shows a dramatic decrease as the sodium density increases. These results can be attributed either to depleted 3d 2D or 4d 2D population due to stimulated electronic Raman scattering (SERS) or to the interference effects recently reported by Malcuit et al. and Krasnikov et al. and treated theoretically by Manykin and Afanas’ev and by Agarwal. It is argued that both mechanisms are operative. Strong ionization and SERS signals were observed at the hybrid resonances corresponding to 3p 2P3/2, 1/2 →4d 2D transitions; however, no excimer lasing at 830 nm was detected. No excimer emission was detected upon two-photon pumping near or at the 3d 2D or ns 2S(n=4, 5, 6) states. Based on these and other observations, the 1 3Σ+g→1 3Σ+u excimer emission is attributed to a molecular Raman process involving stimulated emission or six-wave mixing via a pathway of the type 1 3Σ+u→2hν 3Δu→
j 3Πg→(k 3Πu, l 3Σ +u)→1 3Σ+g→1 3Σ +u .
The Hausdorff dimension of the Smale-Williams solenoid with different contraction coefficients
Authors: Simon Károly 
Published: July 2002

In this paper we prove that the Hausdorff dimension of the Smale-Williams solenoid

Λ
¯

\overline {\Lambda }

with different contraction coefficients

λ
,
μ

\lambda ,\mu

is given by the formula

dim
H

⁡
(

Λ
¯

)
=
1
+

log
⁡
2

log
⁡
(
1

/

max
(
λ
,
μ
)
)

\dim _H(\overline {\Lambda })=1+\frac {\log 2}{\log (1/\max (\lambda ,\mu ))}

. Further, for

λ
,
μ
>

1
8

\lambda ,\mu >\frac 18

we prove that the Hausdorff dimension of each angular section is equal to

log
⁡
2

log
⁡
(
1

/

max
(
λ
,
μ
)
)

\frac {\log 2}{\log (1/\max (\lambda ,\mu ))}

.
GCUA: general codon usage analysis.
Authors: McInerney J O 
Published: July 2002

Abstract
SUMMARY: The program General Codon Usage Analysis (GCUA) has been developed for analysing codon and amino acid usage patterns. AVAILABILITY: ftp://ftp.nhm.ac.uk/pub/gcua. Freely available for academic use, commercial users should contact the author. CONTACT: J.McInerney@nhm.ac.uk
Mitochondrial Sequence Diversity Within a Subspecies of Savanna Monkeys (Cercopithecus aethiops) Is Similar to That Between Subspecies
Authors: Shimada M. K. , Terao K. , Shotake T. 
Published: July 2002

AbstractCercopithecus aethiops can be classified into four subspecies by morphology and by geographic distribution. However, the phylogenetic relationship between these subspecies is unclear. We previously found five distinct haplogroups of mitochondrial DNA (mtDNA) in the subspecies C. aethiops aethiops at the restriction fragment length polymorphism (RFLP) level, and found that those haplogroups are parapatrically distributed in their habitat. To determine the relationship between subspeciation and haplogroup formation in a subspecies, we compared mtDNA control region and 12S rRNA gene sequences (approximately 700 bp) in C. a. aethiops, two other subspecies of C. aethiops, and two species of Cercopithecus. The diversity between haplogroups in C. a. aethiops was almost the same as that between subspecies. This similar level of diversification between and within haplogroups may explain why a previously obtained mtDNA tree did not show monophyletic branching according to subspecies.
Antiferromagnetic–Ferromagnetic Heterostructure‐Based Field‐Free Terahertz Emitters
Authors: Wu Xiaojun , Wang Hanchen , Liu Haijiang , Wang Yizhan , Chen Xinhou , Chen Peng , Li Peiyan , Han Xiufeng , Miao Jungang , Yu Haiming , Wan Caihua , Zhao Jimin , Chen Sai 
Published: August 2022

AbstractRecently, ferromagnetic‐heterostructure spintronic terahertz (THz) emitters have been recognized as one of the most promising candidates for next‐generation THz sources, owing to their peculiarities of high efficiency, high stability, low cost, ultrabroad bandwidth, controllable polarization, and high scalability. Despite the substantial efforts, they rely on external magnetic fields to initiate the spin‐to‐charge conversion, which hitherto greatly limits their proliferation as practical devices. Here, a unique antiferromagnetic–ferromagnetic (IrMn3|Co20Fe60B20) heterostructure is innovated, and it is demonstrated that it can efficiently generate THz radiation without any external magnetic field. It is assigned to the exchange bias or interfacial exchange coupling effect and enhanced anisotropy. By precisely balancing the exchange bias effect and enhanced THz radiation efficiency, an optimized 5.6 nm‐thick IrMn3|Co20Fe60B20|W trilayer heterostructure is successfully realized, yielding an intensity surpassing that of Pt|Co20Fe60B20|W. Moreover, the intensity of THz emission is further boosted by togethering the trilayer sample and bilayer sample. Besides, the THz polarization may be flexibly controlled by rotating the sample azimuthal angle, manifesting sophisticated active THz field manipulation capability. The field‐free coherent THz emission that is demonstrated here shines light on the development of spintronic THz optoelectronic devices.
Targeted organized teaching scripts (TOTS) in the pediatric emergency department
Authors: Sokoloff William C. , Kusulas Matthew P. , Cassara Michael 
Published: August 2022

AbstractIn the pediatric emergency department (PED), considerable challenges inhibit educational opportunities for residents outside of being precepted. The use of teaching scripts specifically addresses these challenges by allowing faculty to have prepared, hyperfocused content that can be delivered in a short time. We developed a series of teaching scripts for 10 high‐yield topics in the PED and assessed their effectiveness at improving educational experiences. Teaching scripts were inconsistently used but well received. Their use also correlated with increased resident satisfaction with clinical teaching. The majority of residents and faculty showed considerable interest in expanding the TOTS program to include additional pediatric emergency medicine topics.
An accurate fully automated panel of plasma biomarkers for Alzheimer's disease
Authors: Palmqvist Sebastian , Stomrud Erik , Cullen Nicholas , Janelidze Shorena , Manuilova Ekaterina , Jethwa Alexander , Bittner Tobias , Eichenlaub Udo , Suridjan Ivonne , Kollmorgen Gwendlyn , Riepe Matthias , von Arnim Christine A.F. , Tumani Hayrettin , Hager Klaus , Heidenreich Fedor , Mattsson‐Carlgren Niklas , Zetterberg Henrik , Blennow Kaj , Hansson Oskar 
Published: August 2022

AbstractIntroductionThere is a great need for fully automated plasma assays that can measure amyloid beta (Aβ) pathology and predict future Alzheimer's disease (AD) dementia.MethodsTwo cohorts (n = 920) were examined: Panel A+ (n = 32 cognitively unimpaired [CU], n = 106 mild cognitive impairment [MCI], and n = 89 AD) and BioFINDER‐1 (n = 461 CU, n = 232 MCI). Plasma Aβ42/Aβ40, phosphorylated tau (p‐tau)181, two p‐tau217 variants, ApoE4 protein, neurofilament light, and GFAP were measured using Elecsys prototype immunoassays.ResultsThe best biomarker for discriminating Aβ‐positive versus Aβ‐negative participants was Aβ42/Aβ40 (are under the curve [AUC] 0.83–0.87). Combining Aβ42/Aβ40, p‐tau181, and ApoE4 improved the AUCs significantly (0.90 to 0.93; P< 0.01). Adding additional biomarkers had marginal effects (ΔAUC ≤0.01). In BioFINDER, p‐tau181, p‐tau217, and ApoE4 predicted AD dementia within 6 years in CU (AUC 0.88) and p‐tau181, p‐tau217, and Aβ42/Aβ40 in MCI (AUC 0.87).DiscussionThe high accuracies for Aβ pathology and future AD dementia using fully automated instruments are promising for implementing plasma biomarkers in clinical trials and clinical routine.