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Changes in the administrative structure of the National Health Service and in policy concerning the role of the psychiatric hospitals in the delivery of mental health care mean that local authorities have a growing responsibility for providing a range of supportive services for people who formerly would have lived for long periods in mental hospitals. Sheltered living environments will be an essential part of these services but there is little systematic information regarding the kind of care required in terms of the needs of the adult mentally ill. A pilot study is reported of the non-hospital residential care experienced by mentally ill adults who were financially assisted by three South London boroughs. The findings are related to a wider study of new long-stay patients in mental hospitals, some of whom could be discharged if alternative services were available. The appropriateness of short-term rehabilitation hostels as opposed to long-term maintenance environments of various kinds is discussed. The study is now being extended to include other forms of care including group homes, sheltered housing schemes and a wider range of local authority hostels than was encountered at the pilot stage.

Microsurgical revascularization in the neck has improved the survival rate of free small-bowel grafts used to replace the cervical oesophagus. Colon vessels are larger than those in the jejunum, and even with naked-eye technique good results have been reported following free colon grafting of the oesophagus. The authors thought it might be possible to achieve even better results using microvascular anastomoses in the neck, and in this way replaced the cervical oesophagus in each of 15 dogs with a free transverse colon autotransplant. Four dogs died during operation and four within three days, two of the latter with graft necrosis. The next seven dogs survived eight days or more, and all their colon grafts were viable. Where patent arteries were demonstrated (three cases) the mucosa and myenteric plexuses of the graft survived. In all four dogs where the arteries were thrombosed or not demonstrated, the mucosa was absent, myenteric plexuses were absent in three, and one graft was grossly stenosed. Among these seven dogs there were three fistulae, one where graft arteries were patent and two where they were not; immediate anastomotic healing was not guaranteed by graft survival or arterial patency.

Conventionally, acquired diverticular disease of the colon has been regarded as a single entity, so far as complications go. Experience at St. Vincent's Hospital, Melbourne, suggests that there are two kinds of diverticular disease, one with the classic muscle abnormality, chiefly confined to the left colon and characterized by inflammatory and perforative complications and the other without muscle abnormality, but with diverticula throughout the colon, in which bleeding is common, perhaps due to a connective-tissue abnormality which, on the one hand, allows development of diverticula in the absence of abnormal intraluminal pressure and, on the other, provides inadequate support for vessels in the diverticular wall or for vascular malformations, which are therefore likely to bleed. Clinical evidence from admissions to St. Vincent's Hospital suggests that both acute and chronic pain may be either inflammatory or associated with muscle spasm and hypertrophy. Finally, there is some evidence to suggest that perforation may be due often, or usually, to abnormal intraluminal pressures rather than to diverticular inflammation.

During experiments designed to test the effect of bacterial contamination and infection upon the healing of colon wounds, fecal specimens removed directly from the dog's colon at colotomy have been examined microbiologically in one (“treated”) group after, and in another (“control”) group without, framycetin medication. The bacterial flora of the dog's colon were found to resemble those in the human colon, and as previously shown in human cases, framycetin completely eliminated coliform organisms from the feces. After closure of such a colotomy wound, an abscess almost always developed in the subcutaneous pouch in which it had been fixed, whether or not the dog had been “prepared” with framycetin, but fewer colonies of organisms grew from the abscesses found in the “prepared” cases, and pus from none of these latter abscesses grew Escherichia coli on culture.

An assessment was made both of the reliability of routine operative cholangiography and of the incidence of unsuspected common duct stones identified by this technique. It is suggested that its disadvantages, in particular the incidence of unnecessary bile duct explorations consequent upon false-positive cholangiograms, make routine operative cholangiography undesirable. If any suspicion of common duct stone exists by virtue of clinical, biochemical or operative findings, an operative cholangiogram should be performed. Following adoption of this policy our findings suggest that the incidence of undetected stone will be negligible.

At St Vincent's Hospital, Melbourne, the number of patients admitted annually with road crash injuries has remained almost constant for the past 14 years. Comparing admissions in the seven years before and during the seven years since enactment of seat belt legislation in Victoria, there has been no change in the proportion of those admitted with abdominal injuries, in the number of associated non-abdominal severe injuries, or in the death rate of those admitted with abdominal injuries. There has, however, been a significant increase in the number of patients admitted with injuries of the gastrointestinal tract and diaphragm. It is suggested that this increase is due to incorrect wearing of the lap component of seat belts with resulting acute abdominal compression.

A comparison has been made of the strength of one and two layer EEA stapled colonic anastomoses measured seven days after their construction in the dog. Bursting pressures were high in both groups and there was no detectable difference between the two groups. Similarly, the e were no obvious differences in the rate of wound infection, the incidence of fibrinous adhesions, and the stage of anastomotic healing as detected on histological examination.

The classical abnormalities found in patients with complete rectal prolapse … wide deep pelvic peritoneal pouch, unsupported redundant rectum with long mesorectum, weak pelvic floor and anal sphincters … are probably effects rather than causes. “Pelvic floor weakness” must explain few cases, since old age, multiparity, uterine prolapse, are found in a minority. The fact that operations which do no more than fix the rectum in the sacral hollow are most successful and often cure incontinence if present is the best evidence that lack of support of the rectum is a prime cause of prolapse … but it is equally likely that such operations work by preventing intussusception, now regarded as the likely mechanism (rather than sliding herniation) of complete rectal prolapse. It is suggested that rectal prolapse is usually due to straining at defaecation against a closed levator-ani … anal-sphincter mechanism, producing prolapse of the rectum rather than incontinence of faeces. Such straining may be obsessive on the part of patients with psychosocial problems and reduced awareness that the rectum is empty; or it may be due to attempted defaecation with a full rectum in patients with reduced rectal sensation, failure of the afferent arc of the ano-rectal reflex and consequent absence of levator-ani … anal-sphincter relaxation.

Sixty-six consecutive patients, admitted to St. Vincent's Hospital, Melbourne, with sigmoid volvulus, fell into two groups, 60 without and six with acquired megacolon. In the former group, flatus tube decompression was usually successful, and sigmoid resection provided a cure. In the group with megacolon, the history was longer; patients more often had bowel symptoms before or between acute episodes of volvulus; flatus tube decompression was rarely successful; and symptoms persisted after sigmoidectomy and were sometimes associated with recurrence of volvulus of the new "sigmoid." It seems that nothing less than total colectomy will cure these patients.

In the five-year period 1972 to 1976 the author's preferred treatment for patients with chronic duodenal or prepyloric peptic ulcer requiring surgery was proximal gastric vagotomy. In spite of this preference, only two-thirds of such patients were so treated. Most patients with bleeding and stenosis were treated by bilateral truncal vagotomy and drainage, and a few by Polya gastrectomy. Proximal gastric vagotomy proved to be a safe elective operation without mortality and with a proven ulcer recurrence rate so far of 6%. Compared with those who had bilateral truncal vagotomy and drainage, the proximal gastric vagotomy patients complained less often of diarrhoea but more often of weight loss and reflux. Two patients have had persistent postprandial non-peptic pain, thought possibly due to upper gastric ischaemia.

Peace is a time for planning and building. It is not merely the absence of war, the destroyer. Surgery has been seen as a war against disease, which must be cut out. Even during peace, trauma is a war of epidemic proportions. Medical professionals now believe prevention is better than cure, and in surgery, much attention is paid not merely to excision, but to repair, reconstruction, and transplantation. Only when there is global peace is it possible for international scientific societies to flourish. Peace provides the opportunity for clinical trials on a large scale and for the exchange of scientists, surgeons, and surgical trainees. The Society has established a Secretariat, a central bureau where requests about acquisition of new skills or details of research opportunities may be directed, advertised, and relayed.

Two patients who had total proctocolectomy for ulcerative colitis 4 and 10 years ago respectively have each been given a new rectum and anal canal, the lower end of a J ileal reservoir being brought through the pelvic floor muscles and joined to a skin wound made in the perineum.

A 76-year-old man presented with recurrent small bowel obstruction, which, at laparotomy, was found to be due to an enterolith which had become distodged from a solitary jejunal diverticulum.

Under the conditions of these experiments, the concomitant development of gross infection (pouch abscess) adjacent to sutured colonic wounds and anastomoses did not prevent macroscopic healing of the bowel in any of the 39 dogs in which such abscesses were found. Bowel preparation with framycetin (used in 17 of 42 dogs) did not produce any obvious difference in macroscopic healing of colonic wounds and anastomoses; nor was there any difference in microscopic healing or resistance to bursting pressure, although the numbers of experiments in these two categories were too small to be significant.

The chief danger of colon operations in the preantibiotic era was thought to be sepsis. Though, no doubt, actual infection of the bowel ends will prevent their healing, it has never been proven that mere contamination with organisms from the faeces or from surrounding peritonitis will produce infection sufficient to cause anastomotic breakdown, provided that the bowel wall is normal and that apposition, blood supply and peritoneal defences are adequate. In order to test specifically the effect of bacterial contamination and infection upon colon wound healing, a dog experimental model has been devised in which other factors affecting colon healing are controlled, and in which concomitant abscess formation is induced adjacent to the healing suture line, peritonitis being avoided by extraperitonealizing the colon in a subcutaneous pouch.

Macroscopic and functional healing of 10 colon anastomoses and 18 colon wounds in all 28 dogs which survived such operations for one week or more took place in spite of the concomitant development of abscesses adjacent to them in 25 of the 28 cases. Histological evidence of inflammation at the suture line was more pronounced the more severe the adjacent infection, but there was inswficient evidence to say whether or not histological healing was delayed or impaired by sepsis of this kind.

The Atlantic Yellow-nosed Albatross (Thalassarche chlororhynchos) breeds only at the Tristan da Cunha archipelago and Gough Island in the central South Atlantic Ocean, and is threatened by mortality from longline fisheries operating in the South Atlantic. Demographic data have been collected from two study colonies on Gough Island and Tristan da Cunha for 20 years. Annual variation in the number of breeding birds was strongly correlated between the two islands, and over the whole study period both study populations have trended downward at around 1.2% per year. The number of established breeders on Gough Island has declined more rapidly, and significantly, at an annual rate of 2.3%. Monitoring established breeders may be a sensitive means of detecting population trends. Average breeding success (67–69%) and breeding frequency (66–65%) were very similar on the two islands. On Gough Island immature and adult annual apparent survival averaged 88 ± 3% and 92 ± 1%, respectively, and apparent survival from fledging to age 5 has averaged 31 ± 8%. Apparent adult survival on Tristan da Cunha averaged only 84 ± 2%. Annual survival of Tristan birds was negatively correlated with longline fishing effort in the South Atlantic Ocean. Population modeling predicts annual rates of decrease of 1.5–2.8% on Gough Island and 5.5% on Tristan da Cunha. Comparison with congeners suggests that the observed and predicted decreases are most likely to be caused by low adult and immature survival. The conservation status of Atlantic Yellow-nosed Albatrosses should be changed from Near Threatened to Endangered. Demografía y Tendencias Poblacionales del Albatros Thalassarche chlororhynchos Resumen. El albatros Thalassarche chlororhynchos sólo se reproduce en el archipiélago Tristan da Cunha y en la isla Gough en el Océano Atlántico Sur central, y se encuentra amenazado debido a la mortalidad causada por las pesqueras de espinel que operan en el Atlántico Sur. Se colectaron datos demográficos durante 20 años en dos colonias reproductivas en el archipiélago Tristan da Cunha y en la isla Gough. La variación anual en el número de aves reproductivas se correlacionó fuertemente entre las dos islas, y durante todo el período de estudio ambas poblaciones han presentado tendencias de decrecimiento de aproximadamente un 1.2% por año. El número de reproductores establecidos en la isla Gough ha disminuido significativamente y más rápidamente, a una tasa anual de 2.3%. El monitoreo de los reproductores que se establecen puede ser un medio sensible para detectar tendencias poblacionales. El éxito reproductivo promedio (67–69%) y la frecuencia de cría (66–65%) fueron muy similares en ambas islas. En la isla Gough la sobrevivencia aparente de inmaduros y adultos fue en promedio de 88 ± 3% y 92 ± 1%, respectivamente. La sobrevivencia de volantones a la edad de 5 años fue en promedio de 31 ± 8%. La sobrevivencia aparente de adultos en Tristan de Cunha fue en promedio sólo de 84 ± 2%. La sobrevivencia anual de las aves de Tristan se correlacionó negativamente con el esfuerzo de la pesca de espinel en el Océano Atlántico Sur. Los modelos poblacionales predicen tasas de disminución anuales de un 1.5–2.8% en la isla Gough y de un 5.5% en Tristan da Cunha. Comparaciones con congéneres sugieren que las disminuciones observadas y predichas son muy probablemente causadas por la baja sobreviviencia de adultos e inmaduros. La categoría de conservación del albatros T. chlororhynchos debería ser cambiada de “casi amenazada” a “en peligro.”

The taxonomy of, and phylogenetic relationships among, African canaries typically assigned to the genus Serinussensu lato (including the putative genera Alario, Pseudochloroptila, i>Serinops, Ochrospiza, Dendrospiza and Crithagra) were investigated, based on 823bp of the mitochondrial cytochrome b gene. Two clades emerged: (1) Palaearctic and Afrotropical taxa, including Serinus serinus, S. canaria, A. alario and the S. canicollis complex (S. c. canicollis, thompsonae and flavivertex), and (2) taxa endemic to the Afrotropics comprising Pseudochloroptila, i>Serinops, Ochrospiza, Poliospiza, Dendrospiza, Poliospiza and Crithagra spp. However, only clade one has jackknife and bootstrap support values above 50. The two clades were separated by Carduelis taxa, suggesting that Serinussensu lato is not monophyletic. As it stands, the phylogeny does not support the recognition of Alario and Serinops and possibly Ochrospiza, Dendrospiza and Pseudochloroptila (Cape siskins) as distinct genera. Alario is sister to Serinus canicollis whereas the others are intermingled in a clade comprised primarily by Crithagra spp. The use of Serinus is confined to the Palaearctic canaries and allied species, and Crithagra for the strictly Afrotropical clade. Since the cytochrome b sequence divergence between the allopatric Cape (S. [c.] canicollis) and Yellow-crowned (S. [c.] flavivertex) canaries (2.8%) was similar to differences between other closely-related species and there are marked plumage differences between these taxa, we suggest that they be elevated to full species rank.Ostrich 2004, 75(4): 288–294

During the period 17–22 December 2001, the onshore distribution and the abundance of Antarctic fur seals Arctocephalus gazella and Subantarctic fur seals A. tropicalis were determined for Prince Edward Island. Two breeding colonies of Antarctic fur seals were located on the south-east coast of the island; the first a mixed (with Subantarctic fur seals) breeding colony with an estimated 24 pups on a vegetated promontory on the northern section of Boggel Beach, and the second, a presumably pure Antarctic fur seal breeding colony with an estimated 380 pups, at Penguin Beach. At a mean intrinsic rate of natural increase of 16.2&#37 per year, Antarctic fur seals appear to be in the rapid recolonization phase of population growth. Breeding colonies of Subantarctic fur seals, largely found on the entire east coast, produced an estimated 15 000 pups, and the population had maintained a mean intrinsic rate of natural increase of some 9.5&#37 per year since 1987/88.Afr. J. mar. Sci. 25: 549–554

The vast majority of communication on the Internet and private networks heavily relies on Public-key infrastructure (PKI). One possible solution, to avoid complexities around PKI, is to use Password Authenticated Key-Exchange (PAKE) protocols. PAKE protocols enable a secure communication link between the two parties who only share a low-entropy secret (password). PAKEs were introduced in the 1990s, and with the introduction of the first security models and security proofs in the early 2000s, it was clear that PAKEs have a potential for wide deployment - filling the gap where PKI falls short. PAKEs’ PKI-free nature, resistance to phishing attacks and forward secrecy are just some of the properties that make them interesting and important to study. This dissertation includes three works on various aspects of PAKEs: an attack on an existing PAKE proposal, an application of PAKEs in login (for password leak detection) and authentication protocols (HoneyPAKEs), and a security analysis of the J-PAKE protocol, that is used in practice, and its variants. In our first work, we provide an empirical analysis of the zkPAKE protocol proposed in 2015. Our findings show that zkPAKE is not safe against offline dictionary attacks, which is one of the basic security requirements of the PAKE protocols. Further, we demonstrate an implementation of an efficient offline dictionary attack, which emphasizes that, it is necessary to provide a rigorous security proof when proposing a new protocol. In our second contribution, we propose a combined security mechanism called HoneyPAKE. The HoneyPAKE construction aims to detect the loss of password files and ensures that PAKE intrinsically protects that password. This makes the PAKE part of the HoneyPAKE more resilient to server-compromise and pre-computation attacks which are a serious security threat in a client-server communication. Our third contribution facilitates the wider adoption of PAKEs. In this work, we revisit J-PAKE and simplify it by removing a non-interactive zero knowledge proof from the last round of the protocol and derive a lighter and more efficient version called sJ-PAKE. Furthermore, we prove sJ-PAKE secure in the indistinguishability game-based model, the so-called Real-or-Random, also satisfying the notion of perfect forward secrecy.; La grande majorité des communications sur internet et sur les réseaux privés repose fortement sur des infrastructures à clé publique (PKI). Une solution possible, pour réduire la complexité induite par les PKIs, consiste à utiliser des protocoles d'échange de clés authentifiés par des mots de passe (PAKE). Les protocoles PAKE permettent une communication sécurisée entre deux parties qui ne partagent qu'un secret de faible entropie (mot de passe). Les PAKEs furent introduits dans les années 1990. Les premiers modèles et preuves de sécurité ont suivi au début des années 2000. Ainsi, il devint clair que les PAKEs ont un potentiel de déploiement à grande échelle - comblant le vide, là où l'infrastructure à clé publique est insuffisante. Le fait que les PAKEs permettent de se passer d'un PKI, leur résistance aux attaques d'hameçonnage et la confidentialité qu'ils offrent ne sont que quelques-unes des propriétés rendant les PAKEs intéressants à étudier. Cette thèse comporte trois nouveaux résultats concernant divers aspects des PAKEs : une attaque sur une proposition PAKE existante, une application de PAKEs permettant la détection de fuites de mots de passe (HoneyPAKEs), et une analyse de sécurité du protocole J-PAKE qui est utilisé dans la pratique. Cette dernière analyse s'appliquant également aux variantes de J-PAKE. Dans notre premier travail, nous proposons une analyse empirique du protocole zkPAKE proposé en 2015. Nos résultats démontrent que zkPAKE n'est pas sûr contre les attaques par dictionnaire hors ligne, qui est l'une des exigences de sécurité de base des protocoles PAKE. De plus, nous exhibons une implémentation d'une attaque par dictionnaire hors ligne efficace qui souligne que lors de la proposition d'un nouveau protocole, qu'il est nécessaire de fournir une preuve de sécurité rigoureuse. Notre seconde propose un mécanisme de sécurité combiné appelé HoneyPAKE. La construction HoneyPAKE vise à détecter la perte de fichiers de mots de passe et garantit que le PAKE utilisé protège intrinsèquement les mots de passe. Cela rend la partie PAKE du HoneyPAKE plus résistante aux compromissions de serveurs et aux attaques par les communications client-serveur. Notre troisième contribution facilite l'adoption plus large des PAKE. Dans ce travail, nous revisitons J-PAKE, en le simplifiant. Cette simplification s'effectue en supprimant une preuve à divulgation nulle non interactive du dernier tour du protocole, résultant ainsi en une version plus légère appelée sJ-PAKE. De plus, nous prouvons que sJ-PAKE est sûr dans le modèle basé sur le jeu de l'indiscernabilité dit réel-ou-aléatoire (real-or-random), satisfaisant ainsi également la notion de secret avançant (forward secrecy).