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PubMedDate not supplied

Which articles and which topics in the forensic sciences are most highly cited?

Forensic science is a multidisciplinary field, which covers many branches of the pure, the applied and the biomedical sciences. Writing-up and publishing research findings helps to enhance the reputation of the investigators and the laboratories where the work was done. The number of times an article is cited in the reference lists of other articles is generally accepted as a mark of distinction. Indeed, citation analysis has become widely used in research assessment of individual scientists, university departments and entire nations. This article concerns the most highly cited papers published in the Journal of Forensic Sciences (JFS) between 1956 and 2005. These were identified with the help of Web-of-Science, which is the on-line version of Science Citation Index, produced by Thomson Institute for Scientific Information (Thomson ISI) with head offices in Philadelphia, USA. This database tracks, among other things, the annual citation records of articles published in several thousand scientific journals worldwide. Those JFS articles accumulating 50 or more citations were identified and rank-ordered according to the total number of citations. These articles were also evaluated according to the name of first author, the subject category of the article, the country of origin and the pattern of co-authorship. This search strategy located 46 articles cited between 50 and 292 times since they first appeared in print. The most highly cited paper by far was by Kasai, Nakamura and White (USA and Japan) concerning DNA profiling and the application of the polymerase chain reaction (PCR) in forensic science. Some forensic scientists appeared as first author on two to three highly cited articles, namely Wetli (USA), Budowle (USA) and Comey (USA). When the highly cited articles were sub-divided into subject category, 15 were identified as coming from toxicology, closely followed by criminalistics (14 articles), pathology (nine articles), physical anthropology (five articles), forensic psychiatry (two articles) and one from odontology. The number of co-authors on these highly cited articles ranged from one to nine and the names of some investigators appeared on as many as four highly cited papers. The vast majority of papers originated from US laboratories although five came from Japan, two each from Sweden and Canada and there was also a joint USA-Swiss collaboration. The Thompson ISI citation databases provide unique tools for tracking citations to individual articles and impact and citation records of scholarly journals.

Bibliometrics↗
PubMed2026

Benchmarking Assembly-Free K-mer Methods for Species Identification in Complex Plant Groups: A Case Study in Populus.

Species identification in taxonomically complex plant groups is frequently limited by the inadequacy of organellar markers, whose phylogenetic signal is disrupted by cytonuclear discordance and chloroplast capture. Using the taxonomically complex genus Populus as a model, we evaluated an assembly-free k-mer workflow against a curated SNP reference benchmark. Whole-genome resequencing data from 235 Populus individuals were curated to a 202-individual, 34-species reference dataset in which all retained species are strictly monophyletic in a genome-wide SNP analysis. Independent maximum likelihood analyses further confirmed that the 31 non-hybrid backbone species each maintained high-support monophyly, while taxa of documented reticulate origin showed placement patterns consistent with their reticulate histories. ABBA-BABA D-statistics detected widespread residual allele sharing within the backbone, though the strongest signals did not correspond to the species pairs responsible for the few k-mer identification failures. Against this benchmark, complete plastomes showed limited resolution, recovering only 3.0% species monophyly and 71.1% nearest-neighbor assignment. The optimized k-mer workflow, operating directly on raw reads without assembly or alignment, recovered 91.2% species monophyly, 99.0% nearest-neighbor assignment, and 98.0% group-average assignment. K-mer length was the primary accuracy-controlling parameter, with k = 31 falling within a stable accuracy plateau. Distance-based metrics reached near-saturation at 0.2× sequencing depth, indicating that low-coverage genome skimming can support scalable nuclear genome-based identification with standard computational resources. K-mer distance heatmaps also flagged unusual genomic affinities in hybrid-origin and outlier samples, providing a rapid screen for subsequent population genomic analyses. These results support assembly-free k-mer distances as an efficient tool for reference-based species identification and sample screening in complex plant groups, with residual limitations concentrated near recently diverged species boundaries. Model-based phylogenomic, coalescent, and network analyses remain necessary for resolving deeper species relationships and detailed introgression histories.

Populus↗
PubMed1996

Hyaluronan distribution in the normal epithelium of esophagus, stomach, and colon and their cancers.

The distribution of hyaluronan (HA) in normal gastrointestinal wall and in tumors originating from their epithelium was studied using a specific probe prepared from cartilage proteoglycan (bHABC, biotinylated hyaluronan binding complex). The normal stratified squamous epithelium of esophagus showed an intense HA staining in the basal and lower intermediate layers, whereas the simple epithelia in the stomach and large intestine were HA negative. Esophageal in situ carcinomas expressed HA also in the cell layers close to the luminal surface, in regions normally negative. Most of the invasive squamous cell carcinomas maintained their HA expression, but in very poorly differentiated types the tumor parenchyma was devoid of HA. In both gastric and colonic adenocarcinomas the tumor parenchyma showed no HA. The stromal tissue was intensely HA positive in all tumors. Cancer cells invading the intestinal smooth muscle were surrounded by copious amounts of HA, whereas the muscular layer was otherwise very poor in HA staining. These results show that relatively well differentiated carcinoma cells themselves retain the high or low HA expression pattern of their original epithelium, whereas tumors stimulate HA deposition in the surrounding stroma.

Colon↗
PubMed2004

The influence of NMDA receptors in the dorsomedial striatum on response reversal learning.

In mammals, the dorsomedial striatum is one brain area shown to be critical for the flexible shifting of response patterns. At present, the neurochemical mechanisms that underlie learning during a shift in response patterns are unknown. The present study examined the effects of NMDA competitive antagonist, DL-2-amino-5-phosphonopentanoic acid (AP-5), injected into the dorsomedial striatum on the acquisition and reversal of a response discrimination. Male Long-Evans rats were tested across two consecutive days in a modified cross-maze. Rats received an infusion of either saline or AP-5 (5 or 25 nmol) 5 min prior to each test session. In the acquisition phase rats learned to turn in one direction (right or left) to receive a cereal reinforcement. In the reversal learning phase rats learned to turn in the opposite direction as in the acquisition phase. In both phases, criterion was achieved when a rat made 10 consecutive correct trials. Infusions of AP-5 did not impair acquisition, but impaired reversal learning of a response discrimination in a dose-dependent fashion. The reversal learning deficit induced by AP-5 resulted from reversions back to the originally learned response pattern following the initial shift. These results suggest that activation of NMDA receptors in the dorsomedial striatum are critical for the flexible shifting of response patterns by enhancing the reliable execution of a new response pattern under changing task contingencies.

2-Amino-5-phosphonovalerate↗
PubMed2004

Learning motion discrimination with suppressed MT.

We studied perceptual learning in motion discrimination when the brain's middle temporal area (MT/V5) was functionally suppressed. This was achieved by using the "paired-dots" motion stimulus where the two dots in a pair always move in counter-phase over a short distance [J. Neurosci. 14 (1994) 7357]. The motion directional signal of the stimulus is therefore always 0 on average. As a result, this stimulus activates MT in Rhesus monkeys no more than flicker noise does [J. Neurosci. 14 (1994) 7367]. We added a new manipulation to eliminate the Glass pattern in the original stimulus that would have otherwise provided a static orientation cue. Two such new motion stimuli were presented sequentially, in a 2AFC task. Subjects decided if the global motion-axis of the stimuli changed clockwise or counter-clockwise. When the task difficulty was set at 60% correct, none of the subjects could learn with feedback, even though their performance was well above chance. However, when the task difficulty was set instead at 70% correct, a new group of subjects was able to learn. Hence, learning motion discrimination was possible when MT was presumably eliminated.

Discrimination Learning↗
PubMedDate not supplied

Multigene analyses identify the three earliest lineages of extant flowering plants.

Flowering plants (angiosperms) are by far the largest, most diverse, and most important group of land plants, with over 250,000 species and a dominating presence in most terrestrial ecosystems. Understanding the origin and early diversification of angiosperms has posed a long-standing botanical challenge [1]. Numerous morphological and molecular systematic studies have attempted to reconstruct the early history of this group, including identifying the root of the angiosperm tree. There is considerable disagreement among these studies, with various groups of putatively basal angiosperms from the subclass Magnoliidae having been placed at the root of the angiosperm tree (reviewed in [2-4]). We investigated the early evolution of angiosperms by conducting combined phylogenetic analyses of five genes that represent all three plant genomes from a broad sampling of angiosperms. Amborella, a monotypic, vessel-less dioecious shrub from New Caledonia, was clearly identified as the first branch of angiosperm evolution, followed by the Nymphaeales (water lillies), and then a clade of woody vines comprising Schisandraceae and Austrobaileyaceae. These findings are remarkably congruent with those from several concurrent molecular studies [5-7] and have important implications for whether or not the first angiosperms were woody and contained vessels, for interpreting the evolution of other key characteristics of basal angiosperms, and for understanding the timing and pattern of angiosperm origin and diversification.

Biological Evolution↗
PubMed2000

Interpreting colonization of the Calathus (Coleoptera: Carabidae) on the Canary Islands and Madeira through the application of the parametric bootstrap.

The Canary Islands have proven to be an interesting archipelago for the phylogeographic study of colonization and diversification with a number of recent studies reporting evolutionary patterns and processes across a diversity of floral and faunal groups. The Canary Islands differ from the Hawaiian and Galapagos Islands by their close proximity to a continental land mass, being 110 km from the northwestern coast of Africa. This close proximity to a continent obviously increases the potential for colonization, and it can be expected that at the level of the genus some groups will be the result of more than one colonization. In this study we investigate the phylogeography of a group of carabid beetles from the genus Calathus on the Canary Islands and Madeira, located 450 km to the north of the Canaries and 650 km from the continent. The Calathus are well represented on these islands with a total of 29 species, and on the continent there are many more. Mitochondrial cytochrome oxidase I and II sequence data has been used to identify the phylogenetic relationships among the island species and a selection of continental species. Specific hypotheses of monophyly for the island fauna are tested with parametric bootstrap analysis. Data suggest that the Canary Islands have been colonized three times and Madeira twice. Four of these colonizations are of continental origin, but it is possible that one Madeiran clade may be monophyletic with a Canarian clade. The Calathus faunas of Tenerife and Madeira are recent in origin, similar to patterns previously reported for La Gomera, El Hierro, and Gran Canaria.

Animals↗
PubMed2005

Cytokeratin expression pattern in congenital and acquired pediatric cholesteatoma.

Pediatric cholesteatoma can be classified as congenital or acquired based on clinical criteria. We studied the expression patterns of five distinctive cytokeratins in both types of cholesteatoma in order to improve understanding of their pathogenesis and origin. A comparable expression pattern for CK10, CK14, CK18, CK19 and 34betaE12 antigens was found in the matrix of congenital and acquired pediatric cholesteatoma. Our results demonstrate that congenital and acquired pediatric cholesteatoma exhibit an identical cytokeratin distribution pattern, suggesting that they share a common origin. Therefore, it seems possible that a portion of the so-called "acquired" cholesteatoma may actually originate from advanced congenital cholesteatoma with secondary destruction of the tympanic membrane in the pediatric patient population.

Child↗
PubMed1993

Characterization of de novo duplications in eight patients by using fluorescence in situ hybridization with chromosome-specific DNA libraries.

Fluorescence in situ hybridization (FISH) with chromosome-specific DNA libraries was performed on samples from eight patients with de novo chromosomal duplications. In five cases, the clinical phenotype and/or cytogenetic evaluations suggested a likely origin of the duplicated material. In the remaining three cases, careful examination of the GTG-banding pattern indicated multiple possible origins; hybridization with more than one chromosome-specific library was performed on two of these cases. In all cases, FISH conclusively identified the chromosomal origin of the duplicated material. In addition, the hybridization pattern was useful in quantitatively delineating the duplication in two cases.

Aneuploidy↗
PubMed1986

Heterogeneity in the pattern of distribution of the axonal collaterals of Purkinje cells in zone b of the cat's vermis: an intracellular HRP study.

Intracellular recordings were obtained from Purkinje cells located in zone b of the vermis; all of the cells were located within lobule V. The ulnar and sciatic nerves were stimulated bilaterally in order to determine the input characteristics of each impaled neuron. Subsequent to recording physiological data the neurons were intracellularly labeled with horseradish peroxidase (HRP). At the conclusion of the experiment the animals were perfused and their brains were processed for HRP histochemistry. Zone b was divided histologically into five 200-micron intervals and the location of each intracellularly injected Purkinje cell relative to these intervals was determined. The input characteristics of Purkinje cells within a single 200-micron interval are not identical. Some Purkinje cells respond exclusively to input from a specific limb, whereas other Purkinje cells within the same interval are activated by both forelimb and hindlimb stimulation. The collaterals of a zone b Purkinje cell form a dense plexus at the Purkinje cell-granule cell junction; branches also distribute to the superficial and deep granule cell layer, as well as to the lower molecular layer. Two patterns of collateral distribution were observed. In one pattern, the plexus has a single arbor confined to the vicinity of the cell body of origin. In the second pattern, at least two arborizations are present. One arbor remains within the vicinity of the cell body of origin whereas other arbors are distant from the parent cell; the two arbors are separated by areas devoid of collaterals. An analysis of the distribution of axonal varicosities shows that they are not uniformly distributed around the cell body of origin in either the sagittal or transverse plane. Cortical areas that contain numerous beads are interspersed between regions that contain few or no varicosities. The discontinuous pattern of distribution and the presence of varicosities in all three cortical laminae suggest that Purkinje cells in zone b have multiple discrete foci of influence on diverse populations of cerebellar neurons. These anatomical findings suggest that individual Purkinje cells may play different functional roles in the local circuitry of zone b. Cells with the spatially confined arbors may be involved with the integration of information within restricted sagittal intervals (approximately 200 micron in width) of the cerebellum. Purkinje cells with the dual arbors have the potential to integrate information over a greater extent of zone b or, in some cases, between zone b and adjacent cortical zones (e.g., c1 or x).

Animals↗
PubMed1989

Immunohistochemical localization of the alpha and beta subunits of S-100 protein in pleomorphic adenoma of the salivary glands.

The immunohistochemical expression of the alpha and beta subunits of S-100 protein in reactive, modified and transformed of myoepithelial cells, salivary pleomorphic was investigated using monoclonal antibodies. With S-100 alpha, normal salivary glands showed strong staining in serous acinar cells and moderate to slight staining in ductal segments, and with S-100 beta staining was slight or negative in acinar cells, but strong in nerve fibres. In pleomorphic salivary adenomas, the immunohistochemical distribution of S-100 alpha and beta proteins indicated great variation in the tumour cells. Some neoplastic cells gave similar staining for both S-100 alpha and beta, others were strongly positive for S-100 alpha and stained only slightly for S-100 beta, or vice versa. Yet other cells were positive for S-100 alpha and negative for S-100 beta, or vice versa. Pleomorphic salivary adenomas were classified both by histopathological criteria and by their staining pattern for S-100 alpha and beta proteins. Great heterogeneity in S-100 alpha and beta protein expression was found in individual tumour cells of both ductal and myoepithelial origin, and no regular pattern was identified. The cellular origin of salivary pleomorphic adenomas is discussed in terms of S-100 alpha and beta protein immunohistochemistry. Pleomorphic adenoma cells may be transformed from reserve cells into tumour cells displaying biologic properties of myoepithelial cells, ductal cells, or a mixture of both.

Adenoma, Pleomorphic↗
PubMed1996

A subharmonic vibratory pattern in normal vocal folds.

This study observes in detail an F0/2 (sounding an octave below an original tone) subharmonic vibratory pattern produced in a normal larynx. Simultaneous electroglottographic and photoglottographic measurements reveal two different open phases within a subharmonic cycle- the first shorter with a simple shape, the second longer with a shape containing a "ripple." Such parameters as the large open quotient (ca. 0.8) and the high airflow values (ca. 1000 cm3/s) distinguish this phonation from the vocal fry (pulse) register. Using an electronic divider to track the subharmonic frequency, a method has been developed to observe the subharmonic vibration of the vocal folds stroboscopically. The stroboscopic visualization reveals an unusual mucosal movement during the "ripple," characterized by an opening movement of the upper margins, which interrupts the closing movement of the vocal folds. An explanation is offered that this vibratory pattern arises as a consequence of detuning of the usually identical frequencies of the dominant modes of the vocal folds, with 3:2 entrainment replacing the normal 1:1 pattern.

Humans↗
PubMed2006

The evolution of spliceosomal introns: patterns, puzzles and progress.

The origins and importance of spliceosomal introns comprise one of the longest-abiding mysteries of molecular evolution. Considerable debate remains over several aspects of the evolution of spliceosomal introns, including the timing of intron origin and proliferation, the mechanisms by which introns are lost and gained, and the forces that have shaped intron evolution. Recent important progress has been made in each of these areas. Patterns of intron-position correspondence between widely diverged eukaryotic species have provided insights into the origins of the vast differences in intron number between eukaryotic species, and studies of specific cases of intron loss and gain have led to progress in understanding the underlying molecular mechanisms and the forces that control intron evolution.

Animals↗
PubMed1995

Evidence of chaotic mood variation in bipolar disorder.

BACKGROUND: Using long-term daily mood records obtained from patients with bipolar disorder and normal subjects, we sought to determine the temporal pattern of mood in bipolar disorder. METHODS: Time series of 1.0 to 2.5 years from seven rapid-cycling patients with bipolar disorder and 28 normal controls were obtained. These were evaluated with several techniques to identify whether the temporal pattern of mood originates from a periodic, a random, or a deterministic source. RESULTS: True cyclicity was not apparent in the power spectra of either the normal subjects or the patients with bipolar disorder. Instead, spectra with a broadband "l/f" shape were observed in both groups, and these spectra were significantly flatter in normal subjects (P = .02). Correlation dimension estimates are a measure of nonlinear deterministic structure, and convergent estimates could be obtained for six of the seven patients with bipolar disorder and none of the normal subjects (P < .001). Additional findings are consistent with these results. CONCLUSIONS: These studies indicate that mood in patients with bipolar disorder is not truly cyclic for extended periods. Nonetheless, self-rated mood in bipolar disorder is significantly more organized than self-rated mood in normal subjects and can be characterized as a low-dimensional chaotic process. This characterization of the dynamics of bipolar disorder provides a unitary theoretical framework that can accommodate neurobiologic and psychosocial data and can reconcile existing models for the pathogenesis of the disorder. Furthermore, consideration of the dynamical structure of bipolar disorder may lead to new methods for predicting and controlling pathologic mood.

Adult↗
PubMed1997

Relax, a novel rat bHLH transcriptional regulator transiently expressed in the ventricular proliferating zone of the developing central nervous system.

A number of basic helix-loop-helix containing proteins have been shown to be required for neural development at different sites or times. Here, Relax, a novel rat basic helix-loop-helix transcriptional regulator, has been isolated and characterized. Analysis of the temporal and spatial distributions shows that the Relax transcripts are detected exclusively in the central nervous system, in discrete regions from embryonic day 11.5 to 18.5. Most strikingly, Relax is expressed along two major boundaries that define the longitudinal axis in the spinal cord and the hindbrain and is a marker of the anterior tip of this axis in the forebrain. Relax-expressing cells are strictly localized in the ventricular zone of the neural tube, where neural progenitors originate. This unique pattern of expression suggests that Relax is involved in neural fate determination.

Animals↗
PubMed2000

Simultaneous chiral separation of triadimefon and triadimenol by sulfated beta-cyclodextrin-mediated capillary electrophoresis.

Enantiomeric separation of two triazole fungicides, triadimefon and triadimenol, was investigated in sulfated beta-cyclodextrin (sulfated beta-CD)-mediated capillary electrophoresis (CE) systems. It was found that, at pH 2-4, sulfated beta-CD exhibited strong chiral recognition towards both triadimefon and triadimenol. The enantiorecognition was believed to result from the multiple interactions between sulfated beta-CD and the analytes, which included inclusion effect, electrostatic interaction, and hydrogen bonding. Under optimal conditions (phosphate buffer with 2% sulfated beta-CD, pH 2.5), simultaneous resolution of all chiral isomers of triadimefon and triadimenol was achieved in less than half an hour. In conjunction with solvent extraction and subsequent enrichment by solid-phase extraction (SPE), this new enantioseparation method was applied successfully in the study of stereoselectivity associated with the biotransformation of triadimefon to triadimenol by soil microorganisms. The present methodology was superior to the commonly adopted chiral gas chromatography (GC) approach in that a very mild procedure was involved from sample extraction to the ultimate chiral separation. Thus, the disturbance of the enantiomeric distribution patterns of the original soil samples by heat stress was an unlikely scenario. Furthermore, it was discovered that, owing to the unique selectivity of the present separation strategy, there was virtually no interference from the soil matrix, which led to improvements in both sensitivity and selectivity in real sample determination.

Buffers↗
PubMed1978

Hemidesmosome-like intercellular specializations in human meningiomas.

Desmosomes, gap junctions and tight junctions are intercellular specializations which have been described in human meningiomas. We report, in five of five meningiomas, including a pulmonary metastasis from a malignant intracranial meningioma, a fourth type of intercellular specialization which is similar to but not identical with the hemidesmosome of the epidermis. Idential intercellular specializations have been described between arachnoidal cells, but not between dural fibroblasts. The presence of the junction in human meningeal neoplasms of diverse histologic pattern supports the origin of the meningioma from arachnoidal epithelium. The consistent occurrence of these structures in a pulmonary metastasis as well as benign intracranial tumors suggests that they may be a useful morphologic marker in the differential diagnosis of putative extracranial metastatic meningiomas.

Aged↗
PubMed1984

Peripheral neuroepithelioma in childhood.

Peripheral neuroepithelioma is a rare and controversial neoplasm that may occur at any age. Fifteen of the 38 previously reported cases have involved children from birth to 17 years of age. The authors observed the course of a 3-month-old girl who presented with an enlarging mass in the left arm and manifested hepatic metastases at the time of diagnosis. The urinary level of vanillylmandelic acid (VMA) was moderately elevated. The primary lesion was excised and metastatic foci showed response to a regimen of vincristine, cyclophosphamide, Adriamycin (doxorubicin), and cisplatin. However, tumor recurred in the brain and liver and the child died 14 months after diagnosis. At autopsy, there was no involvement of adrenal glands or sympathetic ganglia and the liver contained numerous involuted lesions as well as active metastases. It is suggested that this is a unique neoplasm, derived from neural crest but distinct from neuroblastoma, which can be characterized by peripheral origin, a histologic pattern of confluent pseudorosettes, and aggressive clinical behavior.

Adolescent↗