Israel’s breeding avifauna: A century of dramatic change

During the course of the 20th century many changes took place in the area encompassing Israel and the Palestinian Authority (hereafter Israel; ca. 28,000 km²): the human population grew from ca. 650,000 inhabitants during 1900–1903 (Rupin, 1920) to ca. 10 million in 2008, i.e. a 16-fold increase. This population increase was accompanied by an increase in land use for human needs – agriculture, aquaculture, forestry, construction of buildings and roads, etc., and a dramatic rise in the standard of living.Here we compare the status (distribution and abundance) of the 227 bird species that are breeding or have bred in Israel from the beginning of the 20th century to the present day. For each species we documented the environmental factors presumed to have affected it, and examined the effects of taxonomic order, body mass, diet, world and local distribution and nest location on the status of the avifauna. We found that 73.6% of the bird species breeding in Israel had undergone a change in their status during the studied period. While several of the examined factors were significantly related to the observed changes, some of them were also interrelated to some degree, making it difficult to single out the factor responsible for a particular change. The main reasons for the changes were nonetheless assessed as habitat change, introduction of invasive species and poisoning. Habitat change had many forms, most of which are related to agriculture, including irrigation, aquaculture and construction of water reservoirs; but also included afforestation, preservation of the natural forest, urbanization, gardening and the introduction of exotic plants. Habitat change was responsible for a population decline in 64 species and population increase in 62 species. Thirteen species, mostly Falconiformes, were impacted by poisoning. Sixteen invasive species, all of tropical origin, were introduced, of which seven were Psittaciformes. Although changes occurred throughout the country, the birds inhabiting the Mediterranean region were more affected than those inhabiting the desert region, reflecting the denser human population in the former region.     

Radiographic anatomy and barium sulfate contrast study of the gastrointestinal tract of eastern box turtles (Terrapene carolina carolina)

Gastrointestinal disorders are an important cause of morbidity in box turtles (Terrapene carolina Carolina), however published information is currently lacking on the normal radiographic anatomy, transit, and emptying times of the gastrointestinal tract. A total of 15 healthy box turtles were recruited for this prospective, anatomic, reference interval study. Three‐view radiographic series (vertical beam dorsoventral, horizontal beam latero‐lateral, and horizontal beam rostrocaudal views) were acquired prior to contrast administration, and following contrast administration at 0, 20, 40, 60, and 90 min, 2, 4, 8, 12, and 24 h post administration, and every 24 h thereafter until all contrast was eliminated (15 mL/kg barium sulfate diluted to 30% weight per volume was administered via orogastric gavage). Vertical beam dorsoventral and horizontal beam latero‐lateral views were of excellent quality to identify gastrointestinal structures. The horizontal beam rostrocaudal view immediately postcontrast administration provided gastric and pyloric identification but had lesser diagnostic use at later time points due to anatomical superimposition. The gastrointestinal tract was composed of a tubular stomach, a pyloric sphincter near midline, a duodenum with a cranial flexure in the right cranial coelomic cavity, small intestines within the right coelom, a small cecal bulb, and a transverse and descending colon. Contrast media entered the large intestine by 24 h in all turtles, and a pyloro‐colic indentation was noted at the proximal descending colon. The large intestinal emptying was highly variable due to the interindividual variability of contrast sequestration within the cecal bulb. Findings from the current study serve as a reference on the gastrointestinal anatomy, transit, and emptying times in healthy eastern box turtles; and introduce a novel, horizontal beam, rostrocaudal view for gastrointestinal contrast studies in chelonians.     

Radiographic findings and clinical factors in dogs with surgically confirmed or presumed colonic torsion

Colonic torsion is a life‐threatening condition in dogs and radiographic findings for this condition have not been well described. The purpose of this retrospective case series was to describe radiographic findings and clinical signs in a group of dogs with colonic torsion. Inclusion criteria were dogs presenting during the period of 2006 and 2016, and that had abdominal radiography and a surgically confirmed or presumed diagnosis of colonic torsion. For each dog, clinical data were recorded from medical records and imaging findings were recorded from retrieved plain radiographs and positive contrast radiographs in which barium enema was performed. Fourteen dogs met inclusion criteria. Of these, nine dogs had colonic torsion confirmed at surgery, with five dogs having surgical confirmation of colonic congestion or mesenteric torsion. Radiographic findings included segmental distention of the colon (14/14), focal narrowing of the colon (11/14), displacement of cecum (11/14), displacement of descending colon (14/14), and mild to no small intestinal distention (14/14). In cases where barium enema was performed, focal narrowing of the colon and longitudinal striations that course in a helical pattern were identified, termed the “torsion sign.” Vomiting was the most common clinical sign observed (12/14), followed by abdominal pain in a small majority of cases (8/14). Severe abdominal pain and hypovolemic shock were uncommon in the patients reported (3/14). Colonic torsion should be considered as a differential diagnosis for dogs with radiographic segmental colonic distention with displacement of the descending colon and cecum. Barium enema is recommended for more definitive diagnosis.     

随机向量内在相关性的度量及指标聚类方法的改进

用两类所含指标全体所构成的向量的内在相关性度量来刻画两类间的距离,改进了一种指标聚类的方法.为此讨论随机向量的内在相关性度量、改进了的方法及该方法的并类距离单调性等问题.     

Controlling the electronic structure of bilayer graphene

We describe the synthesis of bilayer graphene thin films deposited on insulating silicon carbide and report the characterization of their electronic band structure using angle-resolved photoemission. By selectively adjusting the carrier concentration in each layer, changes in the Coulomb potential led to control of the gap between valence and conduction bands. This control over the band structure suggests the potential application of bilayer graphene to switching functions in atomic-scale electronic devices.