bluuebunny/crossref_metadata_2025_split huggingface dataset:
The long-term dynamics of serum antibodies against SARS-CoV-2
Authors: de Sousa Graziele Fonseca , Nogueira Thuany da Silva , de Sales Lana Soares , Ferreira Maissner Fernanda , Araújo de Oliveira Odara , Rangel Hellade Lopes , dos Santos Daniele das Graças , Nunes-da-Fonseca Rodrigo , de Souza-Menezes Jackson , Nepomuceno-Silva Jose Luciano , Mury Flávia Borges , de Souza Gestinari Raquel , Tanuri Amilcar , Ferreira Jr Orlando da Costa , Monteiro-de-Barros Cintia 
Published: December 2022

ObjectiveTo analyze the long-term dynamics of antibodies against SARS-CoV-2 and understand the impact of age, gender, and viral load on patients’ immunological response.MethodsSerum samples were obtained from 231 COVID-19 positive patients from Macaé, in Rio de Janeiro state, in Brazil, from June 2020 until January 2021. The production of IgA, IgM, IgG, and IgE against S glycoprotein was analyzed using the S-UFRJ assay, taking into account the age, gender, and viral load.ResultsAnalysis of antibody production over 7 months revealed that IgA positivity gradually decreased after the first month. Additionally, the highest percentage of IgM positivity occurred in the first month (97% of patients), and declined after this period, while IgG positivity remained homogeneous for all 7 months. The same analysis for IgE revealed that almost all samples were negative. The comparison of antibody production between genders showed no significant difference. Regarding the age factor and antibody production, patients aged ≥60 years produced almost twice more IgA than younger ones (17–39 years old). Finally, a relationship between viral load and antibody production was observed only for older patients.ConclusionsOur work provides an overview of long-term production of antibodies against SARS-CoV-2, suggesting prolonged production of IgA and IgM antibodies for 3 months and continued IgG production for over 7 months. In addition, it identified a correlation between viral load and IgM titers in the older group and, finally, different IgA production between the age groups.
Development and validation of a nephelometric immunoassay for IgG1 in milk
Authors: COLLIN ROGER , PROSSER COLIN , MCLAREN ROB , THOMSON MARY , MALCOLM DAVID 
Published: July 2002

A nephelometric immunoassay, with a detection range of 0·3 to 5 g IgG1/l, was developed for the determination of immunoglobulin in bovine milk. The assay exhibited no significant cross-reactivity with αS1-casein, αS2-casein, β-casein, κ-casein or β-lactoglobulin and 39% cross-reactivity with IgG2. The nephelometric assay was compared with ELISA and RID (24 h and 48 h incubations) assays using 105 duplicate milk samples covering IgG1 values ranging from 0·45 to 1·8 g1. The results obtained from all assays showed good agreement with the exception of those obtained by the RID assay (24 h incubation) which gave lower results in samples containing more than 1·2 g IgG1/l. It was concluded that the nephelometric assay is a reliable, rapid and convenient method suitable for the quantification of IgG1 in milk. The assay can be configured for routine high-throughput milk quality assurance for IgG1 in dairy laboratories.
The invariant algebraic surfaces of the Lorenz system
Authors: SWINNERTON-DYER SIR PETER 
Published: July 2002

The object of this paper is to find all the irreducible algebraic surfaces which (for
special values of the parameters b, r, s) are invariant under the Lorenz systemx˙ = X(x, y, z) = s(y−x),
y˙ = Y(x, y, z) = rx−y−xz,
ż = Z(x, y, z) =−bz+xy. (1)It is customary in considering the Lorenz system to require the parameters b, r, s to
be all strictly positive; however for this particular problem we shall follow previous
practice in only imposing the condition s ≠ 0. (If s = 0 the equations are trivially
integrable and x is constant on any trajectory; thus x should be regarded as a
parameter and the question discussed in this paper ceases to be a natural one.)
Location-Based Services: Navigation for the Masses, At Last!
Authors: Beatty Colin 
Published: July 2002

This paper, and that following, were first presented at NAV 2001 – Location and Navigation – held at Church House, Westminster, London, 6th to 8th November 2001. Full Proceedings of the Conference are available on CD-ROM from the Royal Institute of Navigation.This paper covers the current status of wireless network location capabilities, including a view of each method describing the strengths and weaknesses of the various approaches. The paper will describe developments in network-assisted GPS to reveal the capabilities of the so-called high sensitivity receivers. The question of what has to be done to get GPS to work indoors will be answered, together with the impact of this capability on the positioning of mobile telephones fitted with GPS capability. The paper discusses the concepts of integrating terrestrial network-derived location with GPS/GNSS and very short range location systems such as Bluetooth. It will explain how Location-Based Services are operated, when they will become widely available, some of the key applications and the impact of this technology on some of the traditional sciences, in particular mapping. This area of navigation is developing extremely rapidly, with potentially a huge market for navigation on land.
The feeding ecology of the striped possum Dactylopsila trivirgata (Marsupialia: Petauridae) in far north Queensland, Australia
Authors: Rawlins D. R. , Handasyde K. A. 
Published: July 2002

AbstractThe diet of striped possums Dactylopsila trivirgata inhabiting the tropical forests of far north Queensland, Australia, was investigated by observing foraging behaviour and analysing stomach samples collected opportunistically from dead animals. In contrast to non‐dactylopsiline petaurids, which frequently use plant exudates as well as invertebrates, observations on the foraging behaviour of D. trivirgata indicate that it is an opportunistic forager feeding mainly on invertebrates. Animals occasionally fed on plant exudates but these contributed little to the diet. Nine different orders of invertebrates were present in stomach samples, with wood boring coleopteran and lepidopteran larvae, and adult hymenopterans and isopterans being most frequently represented in the diet. This is consistent with the unusual morphological characteristics of D. trivirgata's, such as their elongated fourth finger and powerful jaws, which appear to be adaptations for extracting prey such as wood‐boring larvae. Two of the important prey taxa in the diet (alates of Formicidae, and larvae of Cerambycidae) had a very high fat content (44% and 40% of dry weight, respectively) suggesting that the animals may target prey of high nutritional value. Anatomical investigations indicated that, relative to body weight, the digestive tract of D. trivirgata was shorter than that of most other petaurids. These data further support the idea that D. trivirgata is more reliant on invertebrates than other members of the family Petauridae.
Spermatogonia and spermatocyte ultrastructure in Hoplias malabaricus (Teleostei, Characiformes: Erythrinidae)
Authors: Cunha Negrão José Nazareno , de Carvalho Edmir Daniel , Foresti Fausto , Quagio‐Grassiotto Irani 
Published: July 2002

AbstractThe Hoplias malabaricus primary spermatogonium shows a large nucleus, central nucleolus, and low electron‐dense cytoplasm containing nuages. In cysts, they undergo several mitotic divisions with incomplete cytokinesis, giving rise to secondary spermatogonia. These are smaller than the primary spermatogonia and their nuclei have one or two eccentric nucleoli. Spermatocytes I can be identified by the presence of synaptonemal complexes. Spermatocytes II are smaller than spermatocytes I, displaying roughly compacted chromatin. All these cell types remain interconnected by thick‐walled intercellular bridges, which have membranous reinforcements during mitosis and meiosis. These cell types show a well‐developed endomembranous system, one of the centrioles anchored to the plasma membrane and small nuages. Their mitochondria are large and circular, with few cristae. In the last generations of spermatogonia, the mitochondria are smaller, elongate and have more cristae. In the spermatocytes, the mitochondria are small and round. Similarities found in relation to germ cells of other teleosts are discussed.
Oestrous occurrence in captive female Cricetomys gambianus (Rodentia: Cricetidae)
Authors: Malekani M. , Westlin L. M. , Paulus J. J. , Potgieter H. C. 
Published: July 2002

Abstract Cricetomys gambianus is an important source of protein for human consumption in many parts of sub‐Saharan Africa. Wild populations are under considerable hunting pressure, suggesting that captive rearing may be desirable. Successful captive‐breeding programmes require a better understanding of reproductive physiology and behaviour. Eight groups containing a total of 68 C. gambianus females were used to characterize the reproductive pattern, including the occurrence and duration of oestrus, the cycle length, the oestrous cyclicity and the mode of ovulation. These female groups were kept in different social and physical environments and examination of vaginal smears were carried out at different periods. Results of the vaginal cytology examination showed two characteristic stages of the cycle: ‘oestrus’ and ‘anoestrus’. Oestrus appeared on average 1.3 times only in one female during 1 month, but its occurrence varied between 0.4 and two times in a month. The mean oestrous length was 3.3 days and ranged from 1.4 to 7.8 days. The average cycle length was 7.9 days but varied between 3 and 15 days. These results showed an irregular cycle pattern and revealed that C. gambianus may be an induced ovulator. Housing events, such as the presence or the absence of a male and the type of cages or rearing room, and the dry and the rainy seasons did not seem to influence the cycle pattern in this species. Further investigations on the basic reproductive biology of Cricetomys are necessary to provide the basis for developing farming methods that will yield high productivity.
The histology and morphometrics of the major salivary glands of four species of wallabies (Marsupialia: Macropodiae) from Kawau Island, New Zealand
Authors: Lentle R. G. , Hume I. D. , Kennedy M. S. , Stafford K. J. , Potter M. A. , Springett B. P. , Haslett S. 
Published: July 2002

AbstractAllometric analyses of the three major salivary glands of 44 tammar wallabies Macropus eugenii and 58 parma wallabies Macropus parma from Kawau Island, New Zealand, indicate that tammar wallabies have larger parotid glands while parma wallabies have larger mandibular glands. The difference can be related to the importance of cooling in tammars, an arid‐zone species, and the need for greater buffering of forestomach digesta in parma wallabies because of their greater daily food intakes and a higher browse component in their natural diet. Comparisons of sublingual gland size of these two species viewed in terms of their capacity for mucus production suggest that this may be influenced by the need to protect mucosa from mechanical and chemical injury from browse. Sample sizes of brush‐tailed rock‐wallabies Petrogale pencilliata and swamp wallabies Wallabia bicolor were too small for similar statistical comparisons, but they confirmed that salivary gland histology was broadly similar among all four species.
Some Exact Results and New Asymptotics for
Hypergraph Turán Numbers
Authors: MUBAYI DHRUV 
Published: July 2002

Given a family [Fscr ] of r-graphs, let ex(n, [Fscr ]) be the maximum number of edges in an n-vertex
r-graph containing no member of [Fscr ]. Let C(r)4 denote the family of r-graphs with distinct
edges A, B, C, D, such that A
∩
B = C
∩
D = Ø
and A ∪ B = C ∪ D. For s1 [les ] … [les ]
sr, let
K(r) (s1,…,sr) be the complete r-partite r-graph with parts of sizes s1,…,sr.Füredi conjectured over 15 years ago that ex(n,C(3)4) [les ]
(n2) for sufficiently large n. We prove the weaker resultex(n, {C(3)4, K(3)(1,2,4)}) [les ] (n2).Generalizing a well-known conjecture for the Turán number of bipartite graphs, we
conjecture thatex(n, K(r)(s1,…,sr)) = Θ(nr−1/s),where s = Πr−1i=1si.
We prove this conjecture when s1 = … = sr−2 = 1 and(i) sr−1 = 2, (ii) sr−1 = sr = 3, (iii)sr > (sr−1−1)!.In cases (i) and (ii), we determine the asymptotic value of ex(n,K(r)(s1,…,sr)).We also provide an explicit construction givingex(n,K(3)(2,2,3)) > (1/6−o(1))n8/3.This improves upon the previous best lower bound of Ω(n29/11) obtained by probabilistic
methods. Several related open problems are also presented.
Exact Expectations and Distributions
for the Random Assignment Problem
Authors: ALM SVEN ERICK , SORKIN GREGORY B. 
Published: July 2002

A generalization of the random assignment problem asks the expected cost of the minimum-cost matching of cardinality k in a complete bipartite graph Km,n, with independent random
edge weights. With weights drawn from the exponential distribution with intensity 1, the
answer has been conjectured to beΣi,j≥0, i+j<k1/(m−i)(n−j).Here, we prove the conjecture for k [les ] 4, k = m = 5, and k = m = n = 6, using
a structured, automated proof technique that results in proofs with relatively few cases.
The method yields not only the minimum assignment cost's expectation but the Laplace
transform of its distribution as well. From the Laplace transform we compute the variance
in these cases, and conjecture that, with k = m = n
→ ∞, the variance is 2/n + O(log n/n2).
We also include some asymptotic properties of the expectation and variance when k is
fixed.
The use of photographic rates to estimate densities of tigers and other cryptic mammals: a comment on misleading conclusions
Authors: Jennelle Christopher S. , Runge Michael C. , MacKenzie Darryl I. 
Published: July 2002

AbstractThe search for easy‐to‐use indices that substitute for direct estimation of animal density is a common theme in wildlife and conservation science, but one fraught with well‐known perils (Nichols & Conroy, 1996; Yoccoz, Nichols & Boulinier, 2001; Pollock et al., 2002). To establish the utility of an index as a substitute for an estimate of density, one must: (1) demonstrate a functional relationship between the index and density that is invariant over the desired scope of inference; (2) calibrate the functional relationship by obtaining independent measures of the index and the animal density; (3) evaluate the precision of the calibration (Diefenbach et al., 1994). Carbone et al. (2001) argue that the number of camera‐days per photograph is a useful index of density for large, cryptic, forest‐dwelling animals, and proceed to calibrate this index for tigers (Panthera tigris). We agree that a properly calibrated index may be useful for rapid assessments in conservation planning. However, Carbone et al. (2001), who desire to use their index as a substitute for density, do not adequately address the three elements noted above. Thus, we are concerned that others may view their methods as justification for not attempting directly to estimate animal densities, without due regard for the shortcomings of their approach.
Phylogeny and the selectivity of extinction in Australian marsupials
Authors: Johnson Christopher N. , Delean Steven , Balmford Andrew 
Published: July 2002

AbstractRecent studies have suggested that contemporary losses of species are unevenly distributed over phylogenies. Here, we show that species of Australian marsupials are at higher risk if they belong to genera that are species‐poor, old or phylogenetically distinct. Extinction risk in this group is also related to habitat and body size, being higher for species from non‐forested habitats and of intermediate body size. We tested the extent to which the phylogenetic selectivity of extinction was explained by this ecological pattern. We found that while genus size and distinctiveness explain no variation in extinction risk that is not accounted for by habitat and body size, there is a significant residual association of genus age with extinction risk. This suggests that while species in small and distinctive genera are at high risk because they are overrepresented in non‐forested habitats and intermediate body size classes, species in old genera are at higher risk over the range of body sizes and habitats and may be intrinsically vulnerable to extinction.
Fitness heterogeneity and viability of restored populations
Authors: Robert Alexandre , Couvet Denis , Sarrazin François 
Published: July 2002

AbstractWe develop a stochastic model of population viability which explicitly links demography and genetics in order to examine the consequences for extinction dynamics of different levels of heritable fitness variance within a population. We particularly focus on situations in which a local small population is artificially built with individuals that were taken from several large source populations. Our results suggest that different levels of fitness variability within a population (due to partially recessive deleterious alleles rather than local adaptation) have a large influence on its viability. Moreover, the optimal level of fitness variance for maximizing population persistence is a function of the species life‐cycle. Two mechanisms with opposite effects are mainly responsible for the different patterns of extinction obtained depending on the life‐cycle, (1) purging of deleterious alleles, (2) demographic stochasticity. For high growth rate or long‐lived species, a high fitness variance decreases short‐term viability and increases long‐term viability. In contrast, for other cases, a high fitness variance increases both short‐ and long‐term viability.
Electrophysiological and neuropsychological tests for the diagnosis of subclinical hepatic encephalopathy and prediction of overt encephalopathy
Authors: Saxena Nandini , Bhatia Manvir , Joshi Yogendra K. , Garg Pramod K. , Dwivedi Sada Nand , Tandon Rakesh K. 
Published: July 2002

Abstract:  Background: Subclinical hepatic encephalopathy (SHE) features in 30–84% of patients with cirrhosis of the liver. Its clinical significance with regards to progression to overt encephalopathy has however, not been established.Aims: The present study was conducted (i) to compare the diagnostic usefulness of neuropsychological tests with that of electrophysiological (EP) tests in detection of SHE, and (ii) to examine the natural course of SHE.Methods: Seventy‐five‐nonencephalopathic cirrhotics (11 females, 64 males; mean (± SD) age 43.6 (± 11.7) years; mean (± SD) education 11(± 3) years) were studied using a battery of tests for intelligence and memory, the number connection test (NCT), and EP tests viz. electroencephalogram (EEG) and auditory P300 event related potentials (P3ERP). All the patients were followed up for a period of 6 months to 2 years for development of overt encephalopathy.Results: Thirty‐five out of 75(47%) patients were diagnosed to have SHE based on at least one abnormal test result. The P3ERP latencies detected SHE in maximum number of patients (23%) followed by EEG (21%). Nearly 59% of patients with SHE progressed to overt encephalopathy within a mean duration of 4 months. Multivariate analysis showed that prior episode of encephalopathy (RR = 6.3; 95% CI = 2.0–19.7), abnormality on EEG (RR = 7.5; 95% CI = 2.2–25.3), abnormal performance on psychometric battery of tests (RR = 35.2; 95% CI = 4.3–287.3), occurrence of gastrointestinal bleed (RR = 19.3; 95% CI = 4.1–88.9), occurrence of dehydration (RR = 10.7; 95% CI = 2.5–45.4) and infection (RR = 11.4; 95% CI = 2.0–64.4) had significantly higher risk for development of overt encephalopathy.Conclusions: EP methods were more sensitive in detection of SHE. Amongst all the tests used, presence of only an abnormal EEG was significantly associated with development of overt encephalopathy along with the precipitating factors.
Correlation of HBV DNA levels in serum and liver of chronic hepatitis B patients with cirrhosis
Authors: Lee Cha Ze , Huang Guan Tarn , Yang Pei Ming , Sheu Jin Chuan , Lai Ming Yang , Chen Ding Shinn 
Published: July 2002

Abstract:  Aim: We sought to evaluate whether serum HBV DNA levels correlates with the liver free HBV DNA levels in chronic hepatitis B.Methods: Thirty‐three consecutive chronic hepatitis B patients with cirrhosis were included in this study. Twenty cases had detectable serum HBV DNA (> 1.8 pg/ml). All had detectable free liver HBV DNA.Results: There was a strong correlation between the serum and liver HBV DNA levels (P = 0.0018, r = 0.717). Thirteen cases had undetectable serum HBV DNA. Among them, six cases still had detectable liver free HBV DNA. Eight cases were HBeAg‐positive. Among them, seven cases were positive for both serum and liver HBV DNA, and one case was negative for both serum and liver HBV DNA. Twenty‐five cases were HBeAg‐negative and anti‐HBe‐positive. Among them, 13 cases were positive for serum HBV DNA, and 19 cases were positive for liver HBV DNA. No significant difference was noted for positivity of serum HBV DNA or liver free HBV DNA between HBeAg‐positive and HBeAg‐negative groups. The level of serum HBV DNA(491 ± 772 pg/ml versus 203 ± 447 pg/ml, p = 0.07) and liver free HBV DNA (33 ± 81 pg/µg versus 6 ± 15 pg/µg, p = 0.13) was also not statistically different.Conclusion: In conclusion, serum HBV DNA levels is strongly correlated with liver HBV DNA levels in chronic hepatitis B with cirrhosis. Liver free HBV DNA can still be detected in about half of the cirrhotic patients with undetectable serum HBV DNA. Serum HBeAg is not a good predictor of serum or liver HBV DNA levels in cirrhotic patients.
Expression of p57/Kip2 protein in extrahepatic bile duct carcinoma and intrahepatic cholangiocellular carcinoma
Authors: Ito Yasuhiro , Takeda Tsutomu , Sasaki Yo , Sakon Masato , Yamada Terumasa , Ishiguro Shingo , Imaoka Shingi , Tsujimoto Masahiko , Monden Morito , Matsuura Nariaki 
Published: July 2002

Abstract:  Background: Evaluation of the biological character of carcinomas requires understanding of cell cycle regulators. P57 (Kip2) belongs to the Cip/Kip family and is known to be one of the universal negative regulators of cell cycle.Methods: In the present study, therefore, we investigated p57 expression in 37 extrahepatic bile duct carcinomas (BDC) and 28 intrahepatic cholangiocellular carcinomas (CCC).Results: The average p57 labeling index (LI) in BDC and CCC were 60.8 ± 7.9 and 58.6 ± 18.6, respectively, which were significantly lower (p = 0.0008 and p = 0.0408, respectively) than those in normal duct epithelia (73.1 ± 7.9, 70.4 ± 8.2). p57 LI was significantly lower in BDC and CCC cases with biological aggressive phenotypes such as poor differentiation (p = 0.0260 and p = 0.0069), lymph node metastasis (p = 0.0274 and p = 0.0214), high Ki‐67 LI (p = 0.0164 and p = 0.0343) and cyclin D1 overexpression (p = 0.0359 and p = 0.0255).Conclusion: These findings suggest that decreased p57 expression is related to the increased activity of cell proliferation and also the progression of these carcinomas.