bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical Communication: A Case of Hyperostosis due to Hypervitaminosis A in a Cat
Authors: English P. B.
Published: May 2008

Abstract— —A case of hyperostosis in a cat is reported. Evidence indicated that the condition was caused by excessive vitamin A intake, in a predominantly liver diet, over a period of 18 months. The diagnosis, made on the case history and physical findings at examination was confirmed by radiological findings and clinical chemistry. It was further substantiated by autopsy findings. To re‐affirm the clinical findings, photographs of macerated hyperostotic bones are presented. The case is discussed and its features are compared with feline oesteodystrophia fibrosa (osteogenesis irnperfecta, juvenile osteoporosis).

Résumé— —On rapporte un cas d'hyperostose chez le chat. Les faits montrent que la maladie est provoqute par une absorption excessive de vitamine A au cours d'un régime dans lequel prédomine le foie pendant une période de 18 mois.

Le diagnostic établi d'après les commémoratifs et les observations cliniques est confirmé par les observations radiologiques et les analyses biochimiques. Il est aussi renforcé par la suite au cours de l'examen nécropsique. Pour illustrer les constatations cliniques des photographies d'os hypero‐stotiques sont présentées. Le cas est discuté et les faits sont comparés avec l'ostéodystrophie fibreuse du chat (ostéogénèse imparfaite, ostéoporose juvénile).

Zusammenfassung— —Es wird über einen Fall von Hyperostose bei einer Katze berichtet. Der Befund liess darauf schliessen, dass der Zustand durch übermässige Vitamin‐A‐Aufnahme mit einem übenviegend aus Leber bestehenden Futter während eines Zeitraums von 18 Monaten verursacht worden war. Die Diagnose auf Grund der Krankengeschichte und der körperlichen.

Untersuchungsergebnisse wurde durch radiologische und klinisch‐chemische Untersuchung bestätigt. Weiter wurde sie durch den Sektionsbefund verifiziert. Als Belege werden die klinischen Befunde und Photographien der mazerierten hyperostotischen Knochen wiedergegeben. Der Fall wird besprochen und seine Besonderheiten werden mit Osteodystrophia fibrosa der Katze (Osteo‐genesis imperfecta, juvenile Osteoporose) verglichen.
Lactational Tetany in the Cat
Authors: Edney A. T. B.
Published: May 2008

Abstract— —A case of Lactational Tetany in a 3‐year‐old cat is described in detail. The case followed the addition of an orphan kitten to the litter of five 3‐week‐old kittens already suckling. Rapid recovery followed injection of a calcium solution, but a relapse occurred after ten days. The cat again responded well to treatment and remained well. A review of recorded cases is presented briefly and a note on the neurophysiology of tetany is included.

Résumé— —On décrit en détail un cas de Tétanie de Lactation chez un chat de 3 ans. Le cas s'est produit à la suite de l'introduction d'un chaton orphelin dam une portée de cinq chatons âgés de 3 semaines et encore à la mamelle.

Une guérison rapide a fait suite à l'injection d'une solution de calcium mais une rechute se produisit 10 jours après. A nouveau le chat fut sensible au traitement et se remit. On présente brièvement une revue des cas déjàn rapportés dans la littérature. Il est inch une note sur la neuro‐physiologie de la tétanie.

Zusammenfassung— —Ein fall von Laktationstetanie bei einer dreijährigen Katze wird im einzelnen beschrieben. Dieser Fall folgte der Aufnahme eines venvaisten Jungtiers in einen Wurf von fünf 3 Wochen alten gesäugten Jungen. Nach Injektion einer Calciumlösung trat rasch Besserung ein, aber nach 10 Tagen kam es zu einem Rückfall. Die Katze sprach wiederum gut auf die Behandlung an, der ein anhaltender Erfolg beschieden war. Eine kune Übersicht über belegte Fälle und eine Bemerkung über die Neurophysiologie der Tetanie schliessen sich an.
Urography in the Dog by an Intravenous Transfusion Technique
Authors: Borthwick R. , Robbie B.
Published: May 2008

Abstract— —A technique of intravenous urography is described which allows more kidney detail to be demonstrated than with conventional intravenous excretion methods. Its possible value in conditions where other routine methods of contrast urography are not effective or are impracticable is also discussed.
Protein‐Losing Enteropathy in a Dog
Authors: Farrow B. R. H. , Penny R.
Published: May 2008

Abstract— —A protein‐losing enteropathy in a dog is described. There was a history of chronic gastrointestinal upset and examination revealed hypoproteinaemic oedema and ascites. Antemortem laboratory findings indicated a protein‐losing enteropathy and these, together with the results of clinical and necropsy examination, are described.
Dislocation of the Shoulder Joint with Fracture of the Caput Humeri in a Cat
Authors: Bedford P. G. G.
Published: May 2008

Abstract— —An account is given of the successful surgical correction of an unusual orthopaedic condition in a cat.

In the cat, this type of fracture of the caput humeri can be successfully treated along conservative lines, but chronic dislocation of the shoulder joint can only be reduced and stabilized by surgical means.

Résumé— —Compte‐rendu d'une intervention réussie de chirurgie correctrice d'une affection orthopédique peu fréquente chez un chat.

Zusammenfassung— —Es wird über die erfolgreiche chirurgische Korrektur eines ungewohnlichen orthopädischen Zustands ebi einer Katze berichtet.
Fusion of Ossification Centres in the Cat
Authors: Smith R. N.
Published: May 2008

Abstract— —Thirty‐seven kittens from eleven litters have been radiographed and eight others have been completely dissected to provide a record of the times of fusion of the epiphyses of the limb bones. The observations are recorded with reference to individual bones and then to the limbs at approximately monthly intervals. Attention is drawn to the variable presence of the sesamoid bone in the medial head of the gastrocnemius muscle. A comment is made in the discussion on the sequence of fusion of the ossification centres.

Résumé— —Trente sept chatons provenant de II protées ont été radiographiés et huit autres ont été complètement disséqués afin d'établir un rapport sur les moments d'apparition de la soudure des épiphyses des os des membres. Les observations sont notées pour les os pris individuellement et ensuite pour les membres à des intervalles de un mois environ. L'attention est attirée sur la présence inconstante de l'os sésamoide dans la partie moyenne de l'extrêrmité du muscle gastrocnémien. Dans la discussion il est fait un commentaire sur la séquence de la soudure des centres d'ossification.

Zusammenfassung— —37 junge Katzen aus elf Würfen wurden radiographisch untersucht und acht andere vollständig seziert, um Unterlagen über die Zeitpunkte der Verschmelzung der Epiphysen der Extremitätenknochen zu erhalten. Die Beobachtungen wurden in Beziehung zu einzelnen Knochen und dann in Beziehung zu den Extremitäten mit ungefähr monatlichen Abständen gebracht. Die Aufmerksamkeit wird auf die wechselnde Anwesenheit des Sesambeins im medialen Ende des Gastrocnemicus gelenkt. In der Besprechung der Verschmelzungsreihenfolge der Ossifikationszentren wird dies kommentiert.
Radiological Pathology and Diagnosis of Degenerative Joint Disease in the Stifle Joint of the Dog
Authors: Morgan J. P.
Published: May 2008

Abstract— —Preliminary radiographic studies of the stifle joints of twelve young, clinically‐normal and twelve older, clinically‐lame dogs in both non‐weight‐bearing and weight‐bearing conditions were conducted. Radiographic changes of degenerative joint disease were periarticular osteophytes, subchondral bone sclerosis, attrition of subchondral bone, narrowing and collapse of the joint space, subluxation or rotation of the bones forming the joint. Certain of these changes were fully appreciated only on radiographs made in the weight‐bearing position.

Résumé— —L'auteur a effectué une étude radiologique préliminaire de l'articulation rotulienne chez douze jeunes chiens cliniquement normaux et chez douze chiens plus âgés préentant des boiteries, le membre postérieur étant étudié en position de détente et en position d'appui. Les altérations radiologiques de l'arthropathie dégénérative étaient les suivantes: ostéophytes péri‐articulaires, ostéosclérose sous‐chondrale, attrition de l'os sous‐chondral, rétrécissement ou effondrement de la cavité articulaire, subluxation ou rotation des os de l'articulation. Certaines de ces altérations n'étaient pleinement manifestes que sur radiographie du membre en position d'appui.

Zusammenfassung— —Vorläufige Röntgenuntersuchungen der Kniegelenke von zwölf jungen, klinisch normalen und zwölf älteren, klinisch lahmen Hunden im nicht‐lasttragenden und im lasttragenden Zustand wurden durchgeführt. Radiographisch markante Veränderungen durch degenerative Gelenkkrankheiten waren periartikuläre Osteophyten, subchondrale Knochensklerose, Abnutzung subchondralen Knochens, Verengung und Kollabieren des Gelenkraums und Subluxation oder Rotation der das Gelenk bildenden Knochen. Bestimmte dieser Veränderungen wurden vollständig nur auf den Röntgenaufnahmen erkannt, die in den lasttragenden Positionen aufgenommen wurden.
Cataract Extraction: a follow up study (429 cases)*
Authors: Magrane W. G.
Published: May 2008

Abstract— —To achieve the best possible results in cataract surgery it is imperative that:

1. a faultless technique be developed and exercised

2. the extracapsular approach be used whenever possible

3. steroids be used both pre and postoperatively to minimize intraocular reactions and subsequent attending complications.

A success ratio of 80 percent was achieved on a long term study (six months to six years) when the extracapsular technique was employed. On a comparative basis, 40 percent or less success was recorded by the author and other veterinary ophthalmic surgeons reporting on the use of the intra‐capsular method. The use of steroids both pre and postoperatively significantly increases the chances for success when compared to those in which only postoperative steroids were used.

Some general observations are noted during the preoperative period, at the time of surgery, and in the postoperative period.

Résumé— —Pour obtenir lcs meilleurs résultats possibles dans la chirurgie de la cataracte, il est impératif:

1—‐De posséder et d'appliquer une technique irréprochable.

2—‐D'utiliser la voie extracapsulaire lorsque cela est possible.

3—‐D'utiliser les stéroïdes avant et après l'opération afin de diminuer les réactions intraoculaires et leurs complications classiques.

En utilisant la voie extracapsulaire, le pourcentage de réussite sur une étude à long terme (6 mois à 6 ans) est de 80%. Par contre, pour la méihode intracapsulaire, un pourcentage de succès de 40% ou moins a été reporté par l'auteur et dans les comptesrendus d'autres ophtalmologistes vétérinaires. L'utilisation des stéroïdes avant et après l'opération augmente de façon significative les chances de succès par rapport à celles que Ton possède en utilisant les stéroïdes suelement après l'opération.

Il a été noté des observations générates concernant la période préopératoire, le temps chirurgical et la période post‐opératoire.

Zusammenfassung— —Um die bestmöglichen Ergebnisse bei der Kataraktchirurgie zu erzielen, ist es unbedingt erforderlich,

1. eine fehlerlose Methode zu entwickeln und anzuwenden,

2. den extrakapsularen Weg möglichst immer zu wählen,

3. vor und nach der Operation Steroide anzuwenden, um intraokuläre Reaktionen und anch‐liessende Beglietkomplikationen geringzuhalten.

Bei einer langzeitigen Untersuchung (sechs Monate bis sechs Jahre) wurde eine Erfolgsquote von 80% bei Anwendung der extrakapsulären Methode erzielt. Im Vergleich damit wurden vom Autor und anderen tierärztlichen Augenchirurgen bei Anwendung der intrakapsulären Methode nur 40% oder weniger Erfolge erzielt. Die Verwendung von Steroiden vor und nach der Operation erhöht wesentlich die Erfolgschancen im Vergleich mit der Anwendung von Steroiden nur nach der Operation.

Einige allgemeine Beobachtungen während der Periode vor der Operation, zur Zeit des chirurgischen Eingriffs und während der postoperativen Peroide werden mitgeteilt.
Contrast Radiography of the Upper Gastrointestinal Tract in the Dog: A Comparison of Micropulverized Barium Sulfate and U.S.P. Barium Sulfate Suspensions in Clinically Normal Dogs
Authors: Root C. R. , Morgan J. P.
Published: May 2008

Abstract— Sixty upper gastrointestinal radiographic examinations were done on five littennate mongrel dogs to compare a commercial micropulverized barium sulfate suspension and a hand‐mixed U.S.P. barium sulfate suspension. Two different fasting times and three different dosage rates were used. Small bowel transit times were influenced significantly (p>0. 05) by the type of contrast agent employed, but not by the volume of medium or by the duration of fasting. Mucosal pattern, loop visibility, and continuity of contrast material were superior when the commercial preparation was used. Recommended dosages were 8–12 cc/kg for small and medium‐sized dogs and 5–7 cc/kg for large dogs, using the commercial agent, or an equivalent concentration of U.S.P. barium sulfate suspension.

Résumé—Soixante examens radiographiques du tractus gastro‐intestinal supérieur ont été effectués sur 5 portées de chiens métis dans le but de comparer une suspension commerciale de sulfate de barium à l'état micropulvérist et une suspension de sulfate de barium U.S.P. (pharmcacopée des Etats Unis) mélangée à la main. On a utilisé deux temps de jeûne différents et illisible gammes de dosage. Les temps de transit courts étaient influencés de facon significative (p.o, 5) par le type d'agent contrastant utilisé mais non par le volume de milieu ou par la durée de jeûne. L'image de la mu‐queuse, la visibilité des anses intestinales, la continuité du moyen de contraste étaient meilleures aprés utilisation de la préparation commerciale. Les doses recommandées sont 8–12 cc/kg par les animaux de petite et moyenne taille et de 5–7 cc/kg pour les gros chiens, aussi bien avec la préparation commerciale qu'avec une concentration équivalente de suspension de sulfate de bariun U.S.P.

Zusammenfassung— Sechzig Röntgenuntersuchungen des oberen Gastrointestinaltrakts wurden an fünf Bastardhunden des gleichen Wurfs durchgeführt, um eine mikropulverisierte Barium‐sulfatsuspension des Handels mit einer handpräparierten USP‐Bariumsulfatsuspension zu vergleichen Zwei verschiedene Fastenzeiten und drei verschiedene Dosierungen wurden angewendet. Die Durchgangszeiten durch den Dünndarm wirden wesentlich (p<0,05) vom Typ des verwendten Kontrastmittels, aber nicht vom Volumen des Mediums oder der Dauer des Fastens beeinflusst. Das Schleimhautrelief, die Erkennbarkeit der Darmschlingen und die Kontinuierlichkeit des Kontrastmittels waren bei Venvendung des Handelspräparats hervorragend. Die empfohlenen Dosen sind 8–12 ml/kg für kleine und mittelgrosse Hunde und 5–7 ml/kg fur grosse Hunde bei Venvendung des Handelspräparats oder einer äquivalenten Konzentration der USP‐Bariumsulfatsuspension.
Variant Lesions in the Central Nervous System of Dogs and Cats
Authors: Stone A. B.
Published: May 2008

Abstract— Herpes simplex is discussed as a possible cause of encephalitis in the adult canine. Eleven cases are reviewed in the following categories: Herpes encephalitis, meningeal hemorrhage, chronic meningitis, meningeoencephalitis and “degenerative encephalitic process”.

Standard references are cited. Serology, histology and associated clinical symptoms are reviewed.

Résumé— On discute de la possibilité pour 1'Herpex simplex d'entraîner une enctphalite chez le chien adulte. On considère onze cas relevant des catégories suivantes: enctphalite herpétique, hémorragie méningé, méningite chronique, méningo‐encéphalite et “processus de dégénerescence encéphalitique”.

Les référencea correspondantes sont citées. Les symptômes sérologiques, histologiques et cliniques associéS sont passé en revue.

Zusammenfassung— Herpes simplex wird als mögliche Ursache der Encephalitis beim ausge‐wachsenen Hund betrachtet. Elf Fälle der folgenden Kategorien werden besprochen: Herpes encephalitis, meningeale Blutung, chronische Meningitis, Meningoencephalitis und “degenerativer encephalitischer Prozess”.

Es werden Standardquellen zitiert. Serologie, Histologie und diesbezügliche klinische Symp‐tome werden behandelt.
Diaphragmatic Pericardial Hernia
Authors: Finn J. Peter , Martin C. L.
Published: May 2008

Abstract— Diaphragmatic pericardial hernia is a rare condition in all mammals. In domestic species, it has most commonly been described in the dog, usually as an incidental necropsy finding. A clinical response to the condition is not common and has rarely been correctly diagnosed. Clinical necropsy and histopathological observations of a case are described, discussed and compared to previous cases in the literature.

Résume— La hernie diaphragmatique‐péricardique est une affection rarement rencontrée chez tous les mammifères. Dam les espèces domestiques, elle a été plus fréquemment décrite chez le chien, en général, comme une découverte accidentelle d'autopsie. Cet état ne se traduit pas couram‐ment de façon clinique et il a rarement été correctement diagnostiqué. Les observations cliniques, nécropsiques et histologiques concernant un cas sont décrites, discutées et comparées avec les cas antérieurement décrits dans la litttérature.

Zusammenfassung— Diaphragmatische pericardiale hernie ist ein seltener Zustand bein allen Säugetieren. Unter cen Haustieren wurde er am häufigsten beim Hund beschrieben, gewöhnlich als zufälliger Sektionsbefund. Eine klinische Reaktion auf den Zustand ist nicht häufig und wurde selten richtig diagnostiziert. Klinishce, Sektions‐ und histopathologische Beobrachtungen eines Falles werden beschrieben, besprochen und mit früheren Fällen in der Literatur verglichen.
A TechniaueI for the Examination of Lactate Dehydrogenase Isoenzymes in the Dog
Authors: Farrow B. R. H. , Jones R. F.
Published: May 2008

Abstract— A technique and apparatus for the electrophoretic separation and staining of lactate dehydrogenase isoenzymes in canine sera is described. The technique is a modification of the agar gel electrophoretic method of Wieme (1959) and is relatively simple, reproducible and inexpensive, allowing visual and densi tometric evaluation of the relative quantities of each enzyme fraction.

Cellulose acetate and five different types of commercially available agar were examined for their suitability as a support medium for LDH isoenzyme separation using canine sera.

Risumé—On décrit une technique et un appareil pour la séparation électrophorttique et la coloration des enzymes du groupe de la deshydrogénase lactique dans le sérum de chien. La technique at une modification de la méthode électrophorétique en gel d'agar de Wieme (1959) et elle est relativement simple, fidéle et peu couteuse, et elle permet une évaluation visuelle et densimétrique des quantités relatives de chaque fraction enzymatique.

Les qualités de l'acétate de cellulose et de 5 types différents d'agar à notre disposition dam le commerce ont été examiné en temps que milieu support pour la séparation des enzymes du groupe lacto‐deshydrogénase du sérum de chien.

Zusammenfassuug—Eine Methode und die Apparatur für die elektrophoretische Trennung und Färbung von Lactatdehydrogenaseioenzymen in Hundeseren werden beschrieben. Die Methode it eine Modifikation der elektrophoretischen Agargelmethode von Wieme (1959) und relativ einfach, reproduzierbar und billig; sie ermöglicht die visuelle und densitometrische Feststellung der relativen Mengen jeder Fermentfraktion.

Celldoseacetat und fiinf verschiedene Typen handelsmässigen Agars wurden hinsichtlich ihrer Eignung als Trägersubstanz für die LDH‐Isoenzymtrennung von Hundeseren benutzt.
Sequential magnetic resonance imaging changes after suspected global brain ischaemia in a dog
Authors: Timm K. , Flegel T. , Oechtering G.
Published: May 2008

Sequential magnetic resonance imaging studies over a period of 18 months were performed in a two‐year‐old pug dog after suspected global brain ischaemia following an anaesthetic accident. The dog was presented with seizures and neurological deficits consistent with a left brainstem and multifocal/diffuse forebrain lesion after an asymptomatic interval of 72 hours following the ischaemic event. Magnetic resonance imaging scans were performed three hours, six weeks, seven and 18 months after the incident. In the acute stage, signal hyperintensity was evident in the occipital and parietal regions of the cerebral cortex and in both rostral caudate nuclei. Slight involvement of the white matter was also noticed. In the chronic phase, the signal hyperintensity in the affected areas of the cortex was diminished and smaller in size, whereas the white matter did not appear to be compromised anymore.
Poisoning of a dog with the explosive pentaerythrityl tetranitrate
Authors: Potočnjak D. , Barić‐Rafaj R. , Lemo N. , Matijatko V. , Kiš I. , Mrljak V. , Harapin I.
Published: May 2008

A three‐year‐old male Labrador retriever was presented at the Clinic of Internal Medicine, University of Zagreb, Croatia. The owner reported that the dog was ataxic, and this was evident by its markedly unsteady, swaying gait. The dog also had difficulty rising and fell several times while trying to stand. It had come into contact with the explosive, pentaerythrityl tetranitrate, while training to detect explosives. The following clinical symptoms were observed: bradycardia, depression, mild disorientation and a broad‐based stance. The dog had conscious proprioceptive deficits in the hindlimbs, but cranial nerve function was normal except for miosis. Ion scan analysis of the dog’s serum after evaporation of the current phase by mass spectroscopy revealed the presence of fragments that are characteristic of pentaerythrityl tetranitrate. The aim of the present case report was to identify pentaerythrityl tetranitrate poisoning and describe the clinical signs of pentaerythrityl tetranitrate poisoning in dogs. To the authors’ knowledge, there are no published scientific articles on pentaerythrityl tetranitrate poisoning in dogs.
Secondary polycythaemia associated with high plasma erythropoietin concentrations in a dog with a necrotising pyelonephritis
Authors: Kessler M.
Published: May 2008

An 11‐year‐old mixed breed dog was presented with anorexia, apathy and intermittent macrohaematuria, absolute polycythaemia (packed cell volume, 80 per cent; red blood cell, 12·2×106/μl) and elevated erythropoietin concentrations. A renal mass was detected by ultrasonography and, following total nephrectomy, diagnosed as necrotising pyelonephritis. After surgery, the haematological parameters and erythropoietin values returned to normal, suggesting that the pyelonephritis was the cause of the polycythaemia. While secondary polycythaemia because of a non‐neoplastic condition of the kidneys occasionally occurs in human beings, it has only extremely rarely been reported in dogs. This is the first case report of a unilateral pyelonephritis causing secondary polycythaemia in a dog.
Haemothorax associated with Angiostrongylus vasorum infection in a dog
Authors: Sasanelli M. , Paradies P. , Otranto D. , Lia R. P. , DeCaprariis D.
Published: May 2008

Angiostrongylosis was diagnosed in a dog presenting with haemothorax on the basis of detection of Angiostrongylus vasorum first‐stage larvae both in the pleural effusion and in faeces. A one‐year‐old, male, mixed‐breed dog was presented with fever, depression and persistent cough of one month’s duration. Clinical examination revealed temperature of 39·5°C, loud bronchovesicular sounds on thoracic auscultation and attenuated cardiac sounds. Thoracic radiographs showed a moderate bilateral pleural effusion and a diffuse interstitial pulmonary pattern, with an alveolar pattern in one lobe. Routine haematology revealed anaemia and leucocytosis with eosinophilia, basophilia and thrombocytopenia. Coagulation assays showed a consumptive coagulopathy resembling disseminated intravascular coagulation. The relationship between haemothorax and the presence of A vasorum larvae in the pleural effusion is discussed. The dog was successfully treated with fenbendazole until negative for larvae on faecal examination. This case report indicates that A vasorum infection should be considered as a possible aetiological cause of haemothorax in dogs.
Transient leucopenia, thrombocytopenia and anaemia associated with severe acute phenobarbital intoxication in a dog
Authors: Khoutorsky A. , Bruchim Y.
Published: May 2008

A nine‐year‐old Labrador retriever dog was admitted to the emergency unit of the Hebrew University Veterinary Teaching Hospital with acute‐onset tremors and coma. It had recently ingested a large quantity of phenobarbital and had a high serum phenobarbital concentration. On this basis, a diagnosis of acute phenobarbital intoxication was made. Significant leucopenia, thrombocytopenia and mild anaemia developed on the third day after admission. The leucopenia resolved on day 6 and the thrombocytopenia on day 13. The red blood cell count remained low for the next month. The dog was discharged on day 13 at which time it was ambulatory but weak. It was completely recovered clinically eight days later. In summary, high levels of serum phenobarbital as a result of acute intoxication induced pancytopenia, which improved when the serum phenobarbital level was normalised.
Characterization of microsatellite loci in the Hawaiian endemic shrub Schiedea adamantis (Caryophyllaceae) and amplification in related species and genera
Authors: CULLEY T. M. , WELLER S. G. , SAKAI A. K. , PUTNAM K. A.
Published: May 2008

Schiedea adamantis is a rare, perennial shrub endemic to the Hawaiian island of Oahu where it consists of a single population. Using a nonradioactive protocol, 12 microsatellite primers were developed that consisted of di‐, tri‐, penta‐ and hexanucleotide repeats. Using multiplexed reactions, all but two primers exhibited polymorphism with an average of 3.67 alleles per primer. Most primers also amplified in 28 additional Schiedea species, revealing wide applicability across the genus; eight and nine primers also amplified in Honckenya peploides and Silene lanceolata, respectively, related genera in the Caryophyllaceae. This is the first known report of microsatellite primers developed in Schiedea.
Getting serious about maintaining biodiversity
Authors: Blignaut James , Aronson James
Published: May 2008

Biodiversity is neither a marketable good or product, nor a service; it is the living web that connects the tangible and intangible elements of healthy ecosystems, which is the essence of so‐called renewable natural capital. The maintenance of biodiversity is therefore not just an ecosystem service among many—it is the sine qua non of ensuring a sustainable future. That is why the maintenance of biodiversity, partly through the augmentation, or restoration, of renewable natural capital, requires the full attention and action of policy‐makers, practitioners, and scientists concerned with sustainability. This, in turn, requires a new approach to accounting and valuation of ecological restoration of damaged or degraded ecosystems. Here we seek to clarify the relation of biodiversity maintenance to ecosystem services, and to outline a new approach to the economic valuation of the restoration of renewable natural capital. A key element in this approach to economic valuation is the development and application of negative discount rates. Changing the way we think about the discount rate and, more broadly, the way we calculate costs and benefits related to restoration can contribute much to advance the maintenance of biodiversity.
A Cartilage Growth Mixture Model With Collagen Remodeling: Validation Protocols
Authors: Klisch Stephen M. , Asanbaeva Anna , Oungoulian Sevan R. , Masuda Koichi , Thonar Eugene J.-MA. , Davol Andrew , Sah Robert L.
Published: May 2008

A cartilage growth mixture (CGM) model is proposed to address limitations of a model used in a previous study. New stress constitutive equations for the solid matrix are derived and collagen (COL) remodeling is incorporated into the CGM model by allowing the intrinsic COL material constants to evolve during growth. An analytical validation protocol based on experimental data from a recent in vitro growth study is developed. Available data included measurements of tissue volume, biochemical composition, and tensile modulus for bovine calf articular cartilage (AC) explants harvested at three depths and incubated for 13days in 20% fetal borine serum (FBS) and 20% FBS+β-aminopropionitrile. The proposed CGM model can match tissue biochemical content and volume exactly while predicting theoretical values of tensile moduli that do not significantly differ from experimental values. Also, theoretical values of a scalar COL remodeling factor are positively correlated with COL cross-link content, and mass growth functions are positively correlated with cell density. The results suggest that the CGM model may help us to guide in vitro growth protocols for AC tissue via the a priori prediction of geometric and biomechanical properties.
3D Reconstruction and Manufacture of Real Abdominal Aortic Aneurysms: From CT Scan to Silicone Model
Authors: Doyle B. J. , Morris L. G. , Callanan A. , Kelly P. , Vorp D. A. , McGloughlin T. M.
Published: May 2008

Abdominal aortic aneurysm (AAA) can be defined as a permanent and irreversible dilation of the infrarenal aorta. AAAs are often considered to be an aorta with a diameter 1.5 times the normal infrarenal aorta diameter. This paper describes a technique to manufacture realistic silicone AAA models for use with experimental studies. This paper is concerned with the reconstruction and manufacturing process of patient-specific AAAs. 3D reconstruction from computed tomography scan data allows the AAA to be created. Mould sets are then designed for these AAA models utilizing computer aided design∕computer aided manufacture techniques and combined with the injection-moulding method. Silicone rubber forms the basis of the resulting AAA model. Assessment of wall thickness and overall percentage difference from the final silicone model to that of the computer-generated model was performed. In these realistic AAA models, wall thickness was found to vary by an average of 9.21%. The percentage difference in wall thickness recorded can be attributed to the contraction of the casting wax and the expansion of the silicone during model manufacture. This method may be used in conjunction with wall stress studies using the photoelastic method or in fluid dynamic studies using a laser-Doppler anemometry. In conclusion, these patient-specific rubber AAA models can be used in experimental investigations, but should be assessed for wall thickness variability once manufactured.
Validation of an EMG-Driven, Graphically Based Isometric Musculoskeletal Model of the Cervical Spine
Authors: Netto Kevin J. , Burnett Angus F. , Green Jonathon P. , Rodrigues Julian P.
Published: May 2008

EMG-driven musculoskeletal modeling is a method in which loading on the active and passive structures of the cervical spine may be investigated. A model of the cervical spine exists; however, it has yet to be criterion validated. Furthermore, neck muscle morphometry in this model was derived from elderly cadavers, threatening model validity. Therefore, the overall aim of this study was to modify and criterion validate this preexisting graphically based musculoskeletal model of the cervical spine. Five male subjects with no neck pain participated in this study. The study consisted of three parts. First, subject-specific neck muscle morphometry data were derived by using magnetic resonance imaging. Second, EMG drive for the model was generated from both surface (Drive 1: N=5) and surface and deep muscles (Drive 2: N=3). Finally, to criterion validate the modified model, net moments predicted by the model were compared against net moments measured by an isokinetic dynamometer in both maximal and submaximal isometric contractions with the head in the neutral posture, 20deg of flexion, and 35deg of extension. Neck muscle physiological cross sectional area values were greater in this study when compared to previously reported data. Predictions of neck torque by the model were better in flexion (18.2% coefficient of variation (CV)) when compared to extension (28.5% CV) and using indwelling EMG did not enhance model predictions. There were, however, large variations in predictions when all the contractions were compared. It is our belief that further work needs to be done to improve the validity of the modified EMG-driven neck model examined in this study. A number of factors could potentially improve the model with the most promising probably being optimizing various modeling parameters by using methods established by previous researchers investigating other joints of the body.
A Computational Procedure for Prediction of Structural Effects of Edge-to-Edge Repair on Mitral Valve
Authors: Avanzini Andrea
Published: May 2008

Edge-to-edge technique is a surgical procedure for the correction of mitral valve leaflets prolapse by suturing the edge of the prolapsed leaflet to the free edge of the opposing one. Suture presence modifies valve mechanical behavior and orifice flow area in the diastolic phase, when the valve opens and blood flows into the ventricle. In the present work, in order to support identification of potentially critical conditions, a computational procedure is described to evaluate the effects of changing suture length and position in combination with valve size and shape. The procedure is based on finite element method analyses applied to a range of different mitral valves, investigating for each configuration the influence of repair on functional parameters, such as mitral valve orifice area and transvalvular pressure gradient, and on structural parameters, such as stress in the leaflets and stitch tension. This kind of prediction would ideally require a coupled fluid-structural analysis, where the interactions between blood flows and mitral apparatus deformation are simultaneously considered. In the present study, however, an alternative approach is proposed, in which results obtained by purely structural finite element analyses are elaborated and interpreted taking into account the Bernoulli type equations available in literature to describe blood flow through mitral orifice. In this way, the effects of each parameter in terms of orifice flow area, suture loads, and leaflets stresses can be expressed as functions of atrioventricular pressure gradient and then correlated to blood flow rate. Results obtained by using this procedure for different configurations are finally discussed.
The river model of black holes
Authors: Hamilton Andrew J. S. , Lisle Jason P.
Published: May 2008

We present a lesser known way to conceptualize stationary black holes, which we call the river model. In this model, space flows like a river through a flat background, while objects move through the river according to the rules of special relativity. In a spherical black hole, the river of space falls into the black hole at the Newtonian escape velocity, hitting the speed of light at the horizon. Inside the horizon, the river flows inward faster than light, carrying everything with it. The river model also works for rotating (Kerr–Newman) black holes, though with a surprising twist. As in the spherical case, the river of space can be regarded as moving through a flat background. However, the river does not spiral inward, but falls inward with no azimuthal swirl. The river has at each point not only a velocity but also a rotation or twist. That is, the river has a Lorentz structure, characterized by six numbers (velocity and rotation). As an object moves through the river, it changes its velocity and rotation in response to tidal changes in the velocity and twist of the river along its path. An explicit expression is given for the river field, a six-component bivector field that encodes the velocity and twist of the river at each point and encapsulates all the properties of a stationary rotating black hole.
The physics and the chemistry of the heat pad
Authors: Sandnes B.
Published: May 2008

Flexing a metallic disk triggers the crystallization of the supercooled sodium acetate solution contained in commercial heat pads. Many mechanisms have been proposed to explain the apparent nucleation of crystalline material. In this paper a simple experiment is described that demonstrates that nucleation is triggered by preserving seed crystals clamped between opposing metal surfaces. An explanation for the retention of the crystalline particles is the elevated melting point caused by very high local pressures. A series of thermophysical properties of the sodium acetate solution is also measured, including the available enthalpy upon crystallization of the supercooled substance, and liquid and solid phase specific heat capacities.
Isochronous oscillations: Potentials derived from a parabola by shearing
Authors: Antón C. , Brun J. L.
Published: May 2008

Any curve derived from a parabola by shearing is a potential in which the anharmonic vibrations are isochronous, with a period independent of the energy.
The physics of a stove-top espresso machine
Authors: King Warren D
Published: May 2008

The operation of a common type of stove-top espresso machine is analyzed to determine the initial fill conditions required to have the coffee extracted in the optimum temperature range of 90°C–95°C. By using the gas laws and some benchtop experiments, it is shown that the pressure in the vessel increases much more slowly than does the saturated vapor pressure of water at the temperature of the vessel. For any given final temperature, the volume of coffee that can be extracted is linearly proportional to the initial volume of air in the pressure vessel; that is, the higher the fill level, the smaller the volume of coffee that can be extracted. It is also shown that for typical operating conditions for which the water is initially at room temperature, half of the coffee is extracted when the water temperature is below 70°C, which is much less than the desirable temperature, and that hotter coffee extraction temperatures will result if the water is preheated to about 70°C before the pressure vessel is sealed and at least 100ml of air space is left in the vessel. Experiments confirming the analysis use easily obtained equipment and are appropriate for undergraduate laboratory work, with the added attraction that students can enjoy consuming the results of the experiments.
A historical derivation of Heisenberg’s uncertainty relation is flawed
Authors: Marburger John H.
Published: May 2008

Kennard’s 1927 demonstration of the uncertainty relation, cited by Heisenberg as the earliest derivation using the formalism of quantum theory, invokes a trial function that severely limits the class of wave functions for which the uncertainty relation is shown to be valid.
The exact relation between the displacement current and the conduction current: Comment on “Time-dependent generalizations of the Biot–Savart and Coulomb laws,” by D. J. Griffiths and M. A. Heald [Am. J. Phys. 59 (2), 111–117 (1991)]
Authors: Heras José A.
Published: May 2008

I introduce the exact relation between the displacement current ϵ0∂E∕∂t and the ordinary current J. I show that ϵ0∂E∕∂t contains a local term determined by the present values of J plus a nonlocal term determined by the retarded values of J. The nonlocal term implements quantitatively the suggestion made by Griffiths and Heald that the displacement current at a point is a surrogate for ordinary currents at other locations.
Nonlinear source–filter coupling in phonation: Theory
Authors: Titze Ingo R.
Published: May 2008

A theory of interaction between the source of sound in phonation and the vocal tract filter is developed. The degree of interaction is controlled by the cross-sectional area of the laryngeal vestibule (epilarynx tube), which raises the inertive reactance of the supraglottal vocal tract. Both subglottal and supraglottal reactances can enhance the driving pressures of the vocal folds and the glottal flow, thereby increasing the energy level at the source. The theory predicts that instabilities in vibration modes may occur when harmonics pass through formants during pitch or vowel changes. Unlike in most musical instruments (e.g., woodwinds and brasses), a stable harmonic source spectrum is not obtained by tuning harmonics to vocal tract resonances, but rather by placing harmonics into favorable reactance regions. This allows for positive reinforcement of the harmonics by supraglottal inertive reactance (and to a lesser degree by subglottal compliant reactance) without the risk of instability. The traditional linear source–filter theory is encumbered with possible inconsistencies in the glottal flow spectrum, which is shown to be influenced by interaction. In addition, the linear theory does not predict bifurcations in the dynamical behavior of vocal fold vibration due to acoustic loading by the vocal tract.
Effect of an entrained air bubble on the acoustics of an ink channel
Authors: Jeurissen Roger , de Jong Jos , Reinten Hans , van den Berg Marc , Wijshoff Herman , Versluis Michel , Lohse Detlef
Published: May 2008

Piezo-driven inkjet systems are very sensitive to air entrapment. The entrapped air bubbles grow by rectified diffusion in the ink channel and finally result in nozzle failure. Experimental results on the dynamics of fully grown air bubbles are presented. It is found that the bubble counteracts the pressure buildup necessary for the droplet formation. The channel acoustics and the air bubble dynamics are modeled. For good agreement with the experimental data it is crucial to include the confined geometry into the model: The air bubble acts back on the acoustic field in the channel and thus on its own dynamics. This two-way coupling limits further bubble growth and thus determines the saturation size of the bubble.
Statistically motivated design of input signals for modern ultrasonic array systems
Authors: Lingvall Fredrik , Olofsson Tomas
Published: May 2008

Modern array systems allow for excitation of separate elements using arbitrary wave forms. This is utilized in pulse compression and coded excitation techniques to improve the imaging performance. Such techniques are however somewhat inflexible since they use predefined excitation schemes. This paper presents a more flexible method for optimizing the input signals to an ultrasonic array in such a way that the scattering strengths at arbitrarily chosen control points in the insonified object can be estimated with as small an error as possible, measured with a mean squared error criteria. The statistically motivated method is based on a linear model of the array imaging system and the method takes into account both prior information regarding the scattering strengths and measurement errors. The input signals are found by using genetic optimization and are constrained to have finite duration and bounds on the maximum amplitudes. Different constellations of control points, and different signal-to-noise ratios, yield different excitation schemes. The design approach finds multiple selective focal laws when choosing relatively well separated control points and when the control points are closely spaced, the resulting excitations result in more diffuse fields. Because of the flexibility in choosing the control points, the design method will be useful when developing transmission schemes aiming at fast imaging of large image areas using few transmissions.
On the conservation of momentum for a sound pulse reflecting from a pressure-release boundary
Authors: Voronovich A. G.
Published: May 2008

When a “massless” one-dimensional sound pulse (mass of a sound pulse is defined as an integral of the perturbation of density over the pulse length) reflects from a pressure-release boundary, its momentum changes sign. This obviously violates momentum conservation. However, in contrast to the case of an unbounded medium, calculation of the momentum in a bounded region includes a second-order term as well. Apparently, the second-order correction to the linear solution ensures momentum conservation in this case. The purpose of this Letter is to find a concrete form of this second-order correction. It appears that, as a result of the nonlinear interaction of the pulse with a pressure-release boundary, the latter experiences second-order net shift. This leads to the generation of a massive second-order rarefaction pulse whose momentum is directed opposite to the direction of propagation of the pulse itself. Appearance of this pulse ensures total momentum conservation.
Contribution of onset/offset information of modulation to amplitude modulation depth discrimination
Authors: Edwards Derek R. , Lee Jungmee , Andrews Jennifer , Wong Aileen
Published: May 2008

A previous study by [J. Lee, G. Long, and C. Jeung, J. Acoust. Soc. Am. 119, S3332 (2006)] found that information at the onset or offset of modulation could be utilized for improved amplitude modulation (AM) depth discrimination in a continuous carrier condition (carrier presented 250ms earlier and later than the modulator). In this study, the relative contribution of information at the onset or offset of the modulation was examined with an onset-fringe carrier condition (carrier begins 250ms earlier than the modulator) and an offset-fringe condition (carrier ends 250ms later than the modulator). The results suggest that modulation information at the onset might be utilized more than at the offset.
The structure of vocal sounds produced with the mouth closed or with the mouth open in treefrogs
Authors: Gridi-Papp Marcos
Published: May 2008

Frogs and toads mostly call with their mouths shut, unlike many other vertebrates. Sound is generated when air crosses the larynx, but there is no direct airflow to the external environment and radiation occurs at the skin. This study directly compares the acoustic output obtained from euthanized frogs with the mouth open against the output obtained with the mouth closed during activation of the larynx by airflow. With the mouth closed, the vocal sac was inflated and the acoustic energy was concentrated in the same harmonics as in the advertisement call, whereas with the mouth open, energy was spread in a wide range of harmonics. The acoustic output at the dominant frequency was more intense with the mouth closed than with the mouth open. More sound was radiated through the vocal sac and head than through the rest of the body. The spectral differences between open and closed mouth treatments matched the differences observed between natural advertisement calls, produced with the mouth closed, and distress calls, produced with the mouth open. By calling with the mouth closed, treefrogs can potentially produce advertisement calls with the energy concentrated in a narrower frequency range than with the mouth open.
Carrier-dependent temporal processing in an auditory interneuron
Authors: Sabourin Patrick , Gottlieb Heather , Pollack Gerald S.
Published: May 2008

Signal processing in the auditory interneuron Omega Neuron 1 (ON1) of the cricket Teleogryllus oceanicus was compared at high- and low-carrier frequencies in three different experimental paradigms. First, integration time, which corresponds to the time it takes for a neuron to reach threshold when stimulated at the minimum effective intensity, was found to be significantly shorter at high-carrier frequency than at low-carrier frequency. Second, phase locking to sinusoidally amplitude modulated signals was more efficient at high frequency, especially at high modulation rates and low modulation depths. Finally, we examined the efficiency with which ON1 detects gaps in a constant tone. As reflected by the decrease in firing rate in the vicinity of the gap, ON1 is better at detecting gaps at low-carrier frequency. Following a gap, firing rate increases beyond the pre-gap level. This “rebound” phenomenon is similar for low- and high-carrier frequencies.