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Objective. The accuracy of navigation in minimally invasive neurosurgery is often challenged by deep brain deformations (up to 10 mm due to egress of cerebrospinal fluid during neuroendoscopic approach). We propose a deep learning-based deformable registration method to address such deformations between preoperative MR and intraoperative CBCT. Approach. The registration method uses a joint image synthesis and registration network (denoted JSR) to simultaneously synthesize MR and CBCT images to the CT domain and perform CT domain registration using a multi-resolution pyramid. JSR was first trained using a simulated dataset (simulated CBCT and simulated deformations) and then refined on real clinical images via transfer learning. The performance of the multi-resolution JSR was compared to a single-resolution architecture as well as a series of alternative registration methods (symmetric normalization (SyN), VoxelMorph, and image synthesis-based registration methods). Main results. JSR achieved median Dice coefficient (DSC) of 0.69 in deep brain structures and median target registration error (TRE) of 1.94 mm in the simulation dataset, with improvement from single-resolution architecture (median DSC = 0.68 and median TRE = 2.14 mm). Additionally, JSR achieved superior registration compared to alternative methods—e.g. SyN (median DSC = 0.54, median TRE = 2.77 mm), VoxelMorph (median DSC = 0.52, median TRE = 2.66 mm) and provided registration runtime of less than 3 s. Similarly in the clinical dataset, JSR achieved median DSC = 0.72 and median TRE = 2.05 mm. Significance. The multi-resolution JSR network resolved deep brain deformations between MR and CBCT images with performance superior to other state-of-the-art methods. The accuracy and runtime support translation of the method to further clinical studies in high-precision neurosurgery.

Whilst a number of studies have examined the effects of biodiversity conservation on the delivery of ecosystems, they have been often limited by the scope of the ecosystem services (ES) assessed and often suffer from confounding spatial issues. This paper examines the impacts of nature conservation (designation) on the delivery of a full suite of ES across nine case-studies in the UK, using expert opinion. The case-studies covered a range of habitats and explore the delivery of ES from a ‘protected site’ and a comparable ‘non-protected’ site. By conducting pair-wise comparisons between comparable sites our study is one of the first to attempt to mitigate confounding cause and effect factors in relation to spatial context in correlative studies. Protected sites delivered higher levels of ecosystem services than nonprotected sites, with the main differences being in the cultural and regulating ecosystem services. Against expectations, there was no consistent negative impact of protection on provisioning services across the case-studies. Whilst the analysis demonstrated general patterns and differences in ecosystem delivery between protected and non-protected sites, the individual responses in each case-study highlights the importance of the social, biophysical, economic and temporal context of individual protected areas and the associated management.

Little is known about the specific functions of the human cortical structures receiving nociceptive input, their relationship to various dimensions of pain, and the modulation of these inputs by attention. We now review studies demonstrating the subdural potentials evoked by a cutaneous laser stimulus which produces a pure pain sensation by selective activation of cutaneous nociceptors (LEPs). These LEPs were localized over human anterior and middle cingulate (AMCC), somatosensory (S1) and parasylvian (PS) cortices. LEP, lesion and imaging data define pain-related elements within each of these structures: insula and parietal operculum within PS, anterior and middle cingulate cortex, and possibly Brodman's areas 3a, 3b and 1 within SI. LEPs recorded over each of these areas is modulated with laser intensity and evoked pain. Attention to the painful laser produces an increase in the amplitude of LEPs over all three cortical areas and emergence of a late positive potential over ACC alone. These studies provide clear evidence of human cortical structures receiving nociceptive input and the modulation of that input by exogenous (e.g. laser intensity) and endogenous factors (e.g. directed attention).

Strokes and other forms of injury to the central nervous system cause changes in function because of the injuries themselves and indirectly because injuries cause expression of neural plasticity. Studies in humans undergoing neurosurgical procedures for implantation of electrodes for deep brain stimulation and for making lesions in the brain have contributed understanding of both normal and abnormal functions of the somatic sensory system. This chapter will specifically discuss the reorganization of the ventral caudal (Vc) sensory nucleus of the thalamus that occurs in connection with pain conditions after strokes and spinal cord injuries. It is shown that pain is associated with expression of neural plasticity that alters maps of noxious and innocuous stimulation in the thalamus and affect processing of sensory information. Results from studies of neural activity in the thalamus in humans will be compared with results from animal studies.

1-Methylcyclopropene (MCP) copolymerizes rapidly with acrylic and vinyl monomers to form soluble, high molecular weight products containing enchained cyclopropane rings. The high electron availability in the cyclopropene double bond promotes one-to-one alternating copolymerization with sulfur dioxide, maleic anhydride, acrylic acid, acrylonitrile, dialkyl fumarates and acrylic esters. Nonalternating copolymers are obtained with vinyl chloride and vinyl acetate, and attempted copolymerization fails entirely with styrene, α-methylstyrene and isoprene. This pattern of copolymerization reactivity resembles that of highly compressed ethylene. Methylcyclopropene copolymers have high glass temperatures in spite of the small size of the MCP unit. The combination of high Tg and small size allows preparation of copolymers with high Tg having a wide range of ductilities and cohesive energy densities.

At Dr Murray's request, I have during the past winter continued the investigation of Messrs Irvine and Young on the solubility of carbonate of lime in its different forms in sea water (the results of which they submitted to this Society in May 1888); and the following notes of the work done and the results obtained by me, under Mr Irvine's guidance, in the laboratory of the Marine Station, Granton, may be of interest.

Polyethylene is prepared in silver perchlorate solution by initiation with dialkyl peroxydicarbonates at 0–40°C. Saponification of the polymer endgroups yields a product rich in α,ω-diols. Well-known reactions convert the hydroxyl groups to other functional groups. The diol may be condensed with phosgene so as to increase its molecular weight severalfold or crosslinked with silicon tetrachloride to form a network.

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IN May, 1912, I published a paper on " The Inheritance of Coat Color in Horses." It was based on a study of the American saddle horse. I knew at the time of mv investigation that A. H. Sturtevant, of Columbia University, N. Y., had in the hands of the printer a manuscript which gave a summary of all papers published to date on the subject. It was my agreement with him, made at Cold Spring Harbor, N. Y., in 1911, that when his paper was published I was to draw on its material for another summary of the problem involved. Sturtevant's paper, "A Critical Examination of Recent Studies on Colour Inheritance in Horses," was published in the Journal of Genetics, Vol. II, No. 1, Cambridge, England. Sturtevant had published, August, 1910, in the Biological Bulletin, his study of the "Inheritance of Color in the American Harness Horse." Hurst, of England, had based his conclusions on a study of the English thoroughbreds. Wilson had tabulated the color of the Shire, Clydesdale and thoroughbreds; while Harper had given his attention to the French percherons. To these five breeds I am now able to add the records of the saddle horse. It is my purpose to combine the figures and draw some conclusions from them. My apology, if one be necessary, for devoting so much time to the color of the horse is, that this is only a part of a larger study, the determination of the unit characters of the horse. I hold that we can make poor progress in this larger work until we have solved the most obvious ones of these characters. If there is a law governing the transmission of color, may we not infer that a law of somewhat like nature will govern the transmission of the more essential qualities of the horse? If it can be proved 615

The fat cow syndrome developed over a two year period in a 100 cow dairy herd following overfeeding in late lactation and the dry period. It was characterised clinically by a high incidence of parturient paresis and chronic unresponsive ketosis in early lactation. The reproductive performance of the herd was poor throughout this period, with extended calving indices confirming a suggested link between fatty liver and infertility.

It is well known that pseudomorphic changes take place with many minerals. These changes may be either by alteration or displacement. In the case of carbonate of lime they are generally of the former order.Among other work conducted at the Marine Station, Granton, during the past year, a number of experiments were instituted with the view of showing how far carbonate of lime was influenced in this direction by metallic and other salts.Corals, preferably the more porous and soft varieties, were selected for this purpose, and these were exposed to the action of solutions of the following salts:–Chloride of manganese, sulphate of iron, chloride of zinc, chloride of chromium, nitrate of nickel, nitrate of cobalt, nitrate of copper, nitrate of lead, chloride of mercury, chloride of tin, nitrate of silver, phosphate of ammonia.

Radiation polymerization of butadiene proceeds by the ionic route. The polymerization rate increased with decreasing temperature, a characteristic of cationic polymerizations. (T.R.H.)

A case of regional ileo-colitis is presented in which the diagnosis was obscured by a long standing fever for several months before other signs appeared.

Dr. T. H. Morgan who received the 1933 Nobel Prize for his discoveries in the field of Genetics gives us in Embryology and Genetics the known relationship of genetics to embryology. This he is eminently fitted to do as his first field of research during the last decade of the nineteenth century was in embryology. Gradually as the years of the present century passed he turned his attention to the new biological science of genetics. In 1926 he published his Theory of the Gene; the first systematic analysis of the material units of heredity which are passed from parent to offspring. The Theory of the Gene was at first received with some hesitation by biologists; but gradually investigators in the field of genetics have proved the correctness of the theory. Dr. Morgan in his latest volume, Embryology and Genetics, points out the role which the genes play in somatogenesis. Since . . .