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1.The catalytic transformations of 3-methylpentane and 3-methy1-2-pentene were studied on the bifunctional catalyst Pt/Al2O3 (0.6% of Pt) in the range 275–400°.2.In a H2 stream the Pt/Al2O3 catalyst leads to the cyclization of 3-methy1-2-pentene and 3-methyl-pentane to methylcyclopentane. It was discovered that H2 plays an important role in these transformations.3.The theory was expressed that on Pt/Al2O3 the reaction for the C5-dehydrocyclization of alkanes proceeds, even if only partially, via the direct closure of the five-membered ring by the scheme; alkane ? cyclane.

Cranial material of some gorgonopsids has been prepared by the acetic acid technique. A new species, Leontocephalus intactus, has been made for one of the skulls, and generic and specific diagnoses are presented. On the basis of composite information from all the skulls, some aspects of the functional morphology are discussed. From the form of the dentition and the pattern of tooth-wear, it is deduced that besides a direct closure of the jaws, the lower incisors must have been capable of interdigitating between the upper incisors to produce a shearing type of occlusion. This must necessarily have involved a propalinal shift of the lower jaw forwards, relative to the skull. However, there was no possibility of an anterior movement of the articular relative to the quadrate and the quadrate must therefore have been streptostylic. It is shown that the quadrate and squamosal together formed a basically ball-and-socket joint and that the quadrate rotated about a transverse axis, upon the epipterygoid. The epipterygoid itself was probably capable of a limited degree of movement relative to the pterygoid. A restoration of the jaw musculature is suggested, on the basis of new information about the lower jaw. A simple mathematical model is constructed to show the feasibility of the muscle restoration. The functional evolution of the gorgonopsid jaw mechanism and musculature is discussed. The organization of the nasal cavity is described and it is shown that the nasal capsule probably consisted of three parts—an anterior chamber restricted to the dorsal part of the skull, a large, purely olfactory posterior chamber, and a ventro-lateral diverticulum of the posterior chamber, the maxillary sinus. The probable presence of olfactory turbinal cartilages in the latter two parts is indicated. The respiratory air probably passed down a choanal tube, supported by extensive processes of the palatine. Evidence of the course of the naso-lachrymal duct is given. The position of Jacobson’s organ, and a possible function for the septomaxillary foramen, are discussed. On both functional and anatomical grounds, it is argued that the gorgonopsids had no trace of a secondary palate. The origin of the organization of the gorgonopsid snout is discussed. New details of the structure of the braincase are described and the homology of the elements are considered. It is shown that the braincase can be compared to the neurocranium of the mammals in several, but not all respects. On the basis of the internal form of the braincase, a reconstruction of the brain is given, suggesting that the telencephalon was relatively well developed. The phylogenetic position of the gorgonopsids as a whole is considered. They are compared with the Therocephalia and it is concluded that their functional organization, as indicated by an extensive suite of characters, differs radically from that group. The cynodonts are shown to be based on the therocephaliantype of organization and therefore to be relatively unrelated to the gorgonopsids. It is apparent that a common ancestor of the gorgonopsids and the therocephalians could have been but barely advanced over the pelycosaurian-grade of structure. Primitive therapsids from the Russian Kazanian deposits are briefly discussed and it is shown that there is some slight evidence for a dichotomy between them into ‘pregorgonopsid’ and ‘pretherocephalian’ stocks. It is formally proposed that the carnivorous therapsids should be classified into two equal ranks, the Gorgonopsia and the Theriodonta and that they were probably derived separately from the sphenacodont pelycosaurs.

Several cases of malignant glaucoma are presented and a new concept is suggested from these cases and a review of the literature. Malignant glaucoma is redefined as a distinct type of angle closure with a forward movement of the lens and a direct closure of the angle occurring with or without glaucoma surgery. The term direct lens block angle closure is suggested to differentiate it from the more common pupillary block angle closure mechanism. The two types share common factors in their pathogenesis with the essential difference determined by the degree of the forward movement of the lens. The clinical differentiation between the two types of angle closure before surgery is discussed.

In a one-year period we have successfully closed a postmyocardial infarction ventricular septal rupture in four men ranging in age from 44 to 61 years. All are alive, 5 to 15 months postoperatively. The bedside diagnosis can be established by Swan-Ganz catheterization. However, definitive repair should be preceded by left ventriculography and coronary angiography to delineate ventricular aneurysms and associated obstructive coronary artery disease. These defects have an equal incidence with anterior and inferior infarctions. Successful surgical management includes median sternotomy, left ventriculotomy, and early operation. Repair of the defect can usually be accomplished by one of three techniques: direct closure, synthetic cloth patches, or a sandwich closure. Associated coronary artery bypass grafting has been infrequent.

1.A study was made of the catalytic transformations of isopentylcyclopentane in presence of Pt-Al2O3 and Pt-ZrO2 at 450° under a pressure of hydrogen of 20 atrn.2.In presence of platinized alumina isopentylcyclopentane reacts with formation not only of products of the hydrogenolysis of the cyclopentane ring (2,5-dimethyloctane, 5-ethyl-2-methylheptane, and 2-methylnonane), but also of a considerable amount of aromatic hydrocarbons. In this case the latter are formed not only by isomerization of the cyclopentane ring to a cyclohexane ring with subsequent dehydrogenation, but also by direct closure of a six-membered ring, with participation of carbon atoms of the side chain, with formation of a hexahydroindan system, which undergoes dehydrogenation in the six-membered ring and hydrogenolysis in the five-membered ring.3.Under the conditions studied Pt-ZrO2 brings about scarcely any hydrogenolysis of the cyclopentane ring, but is a hydrogenating catalyst for a double bond in the ring.

While perforation of a peptic ulcer in the duodenum is a serious complication, the defect in the intestinal wall can usually be repaired by direct closure or use of an omental patch. A full-thickness pedicle graft offers an alternative procedure, and details of its use are reported.

Two cases of induced anterior tibial compartment syndrome following muscle hernia repair, as well as the pathogenesis of the syndrome, are discussed. The proper surgical treatment of anterior tibial muscle hernia is suggested with an admonition against direct closure of the fascial edges.

Cardiac surgeons have made sporadic attempts to devise a suitable method of closure of atrial septal defects for some time. Cohn1 in 1947 invaginated the atrial wall, sewed it to the edges of experimental defects, and cut loose the fixed portion of the wall. Murray2 in 1948 proposed and used in patients a method of direct closure by suture that appears, from his description of the operation, to resemble the method described below. At the time of writing of Murray's article, one of his patients who seemed clearly to have had an atrial septal defect was doing very well after the operation. Others3 have devised methods of suture or methods using prostheses that have functioned well in animals but have not done well or have not been tried in human beings. Gross and others4 report success in three of six instances of operative closure of atrial