Plate 457. Mutisia Subspinosa Compositae

Mutisia subspinosa Cav. is described and illustrated and its relationships with other members of Mutisia sect. Guariruma (Cass.) Cabrera discussed. Notes on its cultivation are provided along with a historical insight into the collections of Née, made on the Malaspina expedition.     

Animal Rights: A Very Short Introduction David DeGrazia

Abstract

Identification and management of inter-dog aggression is important for animal rescue shelters to reduce the incidence of euthanasia and ensure the safe re-homing of animals. Forty-three shelters responded to a questionnaire which collected information about the management of dogs with inter-dog aggression in rescue shelters. Most shelters (33; 76.7%) admitted dogs reported by relinquishing owners as aggressive to other dogs. Most shelters reported inter-dog aggression as a common problem, affecting either 20–49 percent of dogs received (25 shelters; 58.1%) or 50 percent or more (7 shelters; 16.3%). Twenty-nine shelters reported that less than ten percent of adopted dogs are returned for inter-dog aggression, but some indicated much higher levels. Shelter employees generally reported that after admission, a dog's level of aggression toward other dogs remains stable over time in the shelter. Management of aggressive dogs included humane destruction (37 shelters; 86%) and rehabilitation (20 shelters; 46.5%). Rehabilitation methods for inter-dog aggression included socialization, stress reduction, desensitization and distraction. Respondents expressed varied levels of confidence over the success of their programs. Rehabilitation techniques based on positive reinforcement were viewed as practical, affordable and effective for reducing inter-dog aggression, while less support was given for punishment-based methods. Factors preventing rehabilitation included financial constraints and lack of time, but shelters may be more likely to provide rehabilitation if a practical, scientifically validated program were available. Such a program could potentially increase both the welfare of aggressive dogs and the safety of the public.     

Antifungal methylphenone derivatives and 5-methylcoumarins from Mutisia friesiana

In addition to the known mutisicoumarin A, the aerial parts of the shrub Mutisia friesiana afforded five new methylphenones, two new 5-methylcoumarins and a new related chromone. Their structures were elucidated by spectroscopic methods 13C NMR data for mutisicoumarin A are reported for the first time. Mutisiphenones A and B and mutisicoumarin A showed antifungal activity against the phytopathogenic fungus Cladosporium cucumerinum.     

New insights into the pollen morphology of the genus Mutisia (Asteraceae, Mutisieae)

The pollen morphology from 67 collections representing 52 species of Mutisia was analyzed by means of light, scanning electron and transmission electron microscopy. Pollen of Mutisia is comparable to that of the more widespread type found in Mutisiinae. The pollen grains of the genus are characterized by the spheroidal-subprolate to prolate shape, large size, tricolporate aperture, with mesoaperture, exine Mutisia type, with sculpturing microechinate to rugulate or microechinate-rugulate. This basic pollen type is very variable in size, endoaperture shape, and exine thickness of the pollen grains. A new type of arrangement of columellae was observed in pollen of Mutisia section Mutisia (e.g., M. stuebelli, M. microphylla, and M. sodiroi). It is suggested that it might have harmomegathic significance. The pollen morphology and polymorphism are discussed with regard to functional mechanisms and possible evolutionary significance.     

A Short Note on Short Dispersal Events

We study how the speed of spread for an integrodifference equation depends on the dispersal pattern of individuals. When the dispersal kernel has finite variance, the central limit theorem states that convolutions of the kernel with itself will approach a suitably chosen Gaussian distribution. Despite this fact, the speed of spread cannot be obtained from the Gaussian approximation. We give several examples and explanations for this fact. We then use the kurtosis of the kernel to derive an improved approximation that shows a very good fit to all the kernels tested. We apply the theory to one well-studied data set of dispersal of Drosophila pseudoobscura and to two one-parameter families of theoretical dispersal kernels. In particular, we find kernels that, despite having compact support, have a faster speed of spread than the Gaussian kernel.     

A Win at Short Odds

Patients with esophageal hiatal hernia often have an array of distressing complaints and physical signs that are difficult to interpret. Physiologic and anatomic studies of the gastroesophageal area in the region of the esophageal hiatus of the diaphragm indicate the existence of a three-in-line sphincter group, consisting of the inferior esophageal constrictor, diaphragmatic pinchcock and cardioesophageal junction. These mechanisms, acting in unison, prevent regurgitation in normal persons.It also can be deduced from clinical, radiologic and experimental data that anatomic disturbances at the esophageal hiatus account for physiologic alterations. A reasonable explanation for the symptoms and signs of esophageal hiatal hernia can be made on the basis of the functional competence of the three-in-line sphincter mechanisms.     

A Short History of Biosemiotics

Biosemiotics is the synthesis of biology and semiotics, and its main purpose is to show that semiosis is a fundamental component of life, i.e., that signs and meaning exist in all living systems. This idea started circulating in the 1960s and was proposed independently from enquires taking place at both ends of the Scala Naturae. At the molecular end it was expressed by Howard Pattee’s analysis of the genetic code, whereas at the human end it took the form of Thomas Sebeok’s investigation into the biological roots of culture. Other proposals appeared in the years that followed and gave origin to different theoretical frameworks, or different schools, of biosemiotics. They are: (1) the physical biosemiotics of Howard Pattee and its extension in Darwinian biosemiotics by Howard Pattee and by Terrence Deacon, (2) the zoosemiotics proposed by Thomas Sebeok and its extension in sign biosemiotics developed by Thomas Sebeok and by Jesper Hoffmeyer, (3) the code biosemiotics of Marcello Barbieri and (4) the hermeneutic biosemiotics of Anton Marko?. The differences that exist between the schools are a consequence of their different models of semiosis, but that is only the tip of the iceberg. In reality they go much deeper and concern the very nature of the new discipline. Is biosemiotics only a new way of looking at the known facts of biology or does it predict new facts? Does biosemiotics consist of testable hypotheses? Does it add anything to the history of life and to our understanding of evolution? These are the major issues of the young discipline, and the purpose of the present paper is to illustrate them by describing the origin and the historical development of its main schools.