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Water is widely regarded as the most essential of natural resources, yet freshwater systems are directly threatened by human activities (1-3) and stand to be further affected by anthropogenic climate [...], Protecting the world's freshwater resources requires diagnosing threats over a broad range of scales, from global to local. Here we present the first worldwide synthesis to jointly consider human and biodiversity perspectives on water security using a spatial framework that quantifies multiple stressors and accounts for downstream impacts. We find that nearly 80% of the world's population is exposed to high levels of threat to water security. Massive investment in water technology enables rich nations to offset high stressor levels without remedying their underlying causes, whereas less wealthy nations remain vulnerable. A similar lack of precautionary investment jeopardizes biodiversity, with habitats associated with 65% of continental discharge classified as moderately to highly threatened. The cumulative threat framework offers a tool for prioritizing policy and management responses to this crisis, and underscores the necessity of limiting threats at their source instead of through costly remediation of symptoms in order to assure global water security for both humans and freshwater biodiversity.

We studied the effects of upwelling on nutrient and phytoplankton dynamics in the pelagic and littoral zones of Lake Tanganyika near Kigoma, Tanzania. During the dry season of 2004, a rise in the thermocline and sudden drop in surface water temperatures indicated a substantial upwelling event. Increases in concentrations of nitrate, soluble reactive phosphorus, and silica in the surface waters occurred simultaneously after the temperature drop. Within days, chlorophyll a concentrations increased and remained elevated, while inorganic nutrient concentrations returned to preupwelling levels and organic nutrient concentrations peaked. We observed parallel temporal patterns of water temperature, nutrient concentrations, and phytoplankton chlorophyll in both the pelagic and the littoral zones, demonstrating that upwelling strongly affects the nearshore ecosystem as well as the pelagic zone. Concurrent records from 12 littoral sites indicated spatial variation in the timing, magnitude, and biological response to upwelling. There was no discernable latitudinal pattern in the timing of upwelling, suggesting that mixing did not result from a progressive wave. Our monitoring, as well as other multiyear studies, suggests that dry-season upwelling occurs during most years in northern Lake Tanganyika. The observed sensitivity of littoral nutrients and phytoplankton to upwelling suggests that reductions in upwelling due to global climate change could strongly affect the dynamics of the spectacular nearshore ecosystem of Lake Tanganyika, as has been proposed for the pelagic zone.

S.J. McAree [1] A.P. Catterall [1,2] S.M. Greenfield [1,2] P.B. McIntyre [1] (1.) QE 2 Hospital, Weiwyn Garden City; (2.) Liszcr Hospital, Stevenage, UK Introduction: The treatment of Pancreatic cancer [...]

Background: Acute upper gastrointestinal haemorrhage (AUGIH) is a common emergency with mortality in excess of 10%. Retrospective analysis of a large number of cases has established the risk factors that [...]

Anthropogenic sedimentation poses a serious threat to littoral communities in the East African rift lakes. Herbivorous fishes may be particularly susceptible due to reduced accessibility and quality of food resources. We studied the effects of sedimentation on two algivorous cichlids, Tropheus brichardi and Petrochromis polyodon, at sediment-disturbed and reference sites along the northeastern shore of Lake Tanganyika. T. brichardi uses fused oral combs to graze filamentous algae, whereas P. polyodon gleans unicellular algae using mobile pads of brush-like teeth. Our results show that sedimented sites have a higher proportion of inorganic matter and less total algae than reference sites, confirming that food quantity and quality are decreased. T. brichardi are more aggressive at sedimented sites, suggesting that decreased food quality increases the importance of defending feeding territories. The territoriality of P. polyodon does not appear to be influenced by sedimentation, though their grazing frequency is significantly reduced. The added bulk of inorganic sediments at disturbed sides may have a salting effect. In contrast to these behavioral shifts, population densities, gut length, and body condition of T. brichardi and P. polyodon are similar at disturbed and reference sites. This suggests that behavioral plasticity alleviates the effects of sedimentation on these algivorous fishes.

Co-evolution has been invoked as an explanation for Lake Tanganyika's unusual endemic fauna. The crabs Platytelphusa armata and Potamonautes platynotus are endemic molluscivores, found in the same habitats as the gastropods Lavigeria coronata, L. nassa and L. grandis. As these are the largest snails in the Lavigeria species flock, and live exposed on rocks, we tested whether shell size and sculpture provides protection from predation. We compared the relative susceptibility of six different size classes of snails to predation by P. armata and P. platynotus in laboratory experiments and tested significance with logistic regressions. Our results indicate that P. armata, the more derived of the two crabs, is a more effective predator than P. platynotus. L. coronata, the most sculptured snail, was more frequently damaged but less frequently killed than L. grandis. L. nassa, with intermediate sculpturing, showed intermediate resistance. Finally, all three species of gastropods were killed only in the smallest three size classes, were damaged in the middle classes, and resistant to shell crushing in the largest class. Our results strongly support the idea of an ongoing evolutionary arms race in the endemic fauna of this lake, with large size and sculpture serving as a refuge for the gastropods from crab predation.

Few large prospective studies of adverse reactions after bacille Calmette-Guérin (BCG) vaccination are available. In a prospective national study of such adverse reactions among 918 subjects (aged 1 day to 54 years) over a 14-month period, 45 vaccinees (5%) reported 53 adverse reactions (23 injection-site abscesses, 14 severe local reactions, 10 cases of lymphadenitis, and 6 other reactions). Only 1% of vaccinees required medical attention. Reactions, particularly lymphadenitis, were significantly less common in infants <6 months old (but not in subjects aged ≥ 6 months) vaccinated by trained (vs. untrained) providers (relative risk [RR], 0.24; 95% confidence interval [CI], 0.09-0.68). Injection-site abscesses (RR, 2.96; 95% CI, 1.11-7.90) and severe local reactions (RR, 4.93; 95% CI, 1.11-21.90) were significantly more common in older vaccinees. Local reactions were more frequently reported by adult females than by adult males (RR, 7.18; 95% CI, 1.59-32.45). Adverse reactions were not significantly associated with any currently available vaccine batch, previous receipt of BCG vaccine, or concomitant administration of other vaccines. [ABSTRACT FROM AUTHOR]

Approximately 650 bed days are used by patients admitted with upper gastrointestinal haemorrhage (UGIH) per annum in this hospital serving a population of 250 thousand. 145 of these are for patients with low risk UGIH (pre-endoscopy Rockalls scores 0 and 1). There are few data on clinical outcomes and no published prospective studies in this group. A previous hospital audit confirmed safe outcome of Iow risk UGIH. We investigated the outcome of outpatient management of patients with Iow risk UGIH. Methods: Hospital policy was changed from 1 June 2002 to avoid admission of patients presenting with Iow risk UGIH. An UGIH clerking proforma was developed to aid and direct assessment of patients and for audit purposes. All patients with UGIH have a pre- and post-endoscopy Rockall score calculated. Low risk patients (score of 0 or 1) are assessed by a senior member of the on-call medical team before discharge. Emergency outpatient UGI endoscopy is arranged on the next working morning. All patients are phoned 30 days later. Results: In 18 weeks 53 patients presented with UGIH. 26 had pre-endoscopy scores of 0 or 1 (49%, 14M:12F), age range 18-78 years (mean 50). 13/26 were discharged (50%), only one did not present for UGI endoscopy as planned. None required admission following endoscopy. 7/13 (58%) had a normal endoscopy, 2 required OPA, 3 further investigations. 1 patient (diagnosis DU) had possible ongoing melaena at 30 days in spite of OPA review (had not taken prescribed medication). Of the 13 iow risk patients admitted, 11 had UGI endoscopy, 3/11 (27%) were normal. All admissions were for other medical issues. The median length of hospital stay was 5 days. Conclusions: Discharge from A&E of Iow risk patients presenting with UGIH with plans for early emergency outpatient UGI endoscopy appears safe and cost effective. An estimated 72 bed-days may be saved per annum in this hospital. In a UK population of 58.8 million this represents potentially a saving of 17... [ABSTRACT FROM AUTHOR]

Background: Guidelines from the DOH guarantee a specialist sees everyone with suspected cancer within 2 weeks of urgent GP referral. Symptom guidelines for suspected upper Gl cancers were distributed. Aims: To evaluate the symptom guidelines for identifying oesophageal cancer. To assess delays in the patient pathway by comparing time from urgent referral to first hospital appointment (endoscopy or outpatients), before and after the guidelines were introduced, and waiting times to first endoscopy in those with benign and malignant dysphagia. Methods: Patients with oesophageal cancer were identified from PAS and endoscopy, for the 1 year before and after the guidelines were introduced. A sample of age/sex matched patients with benign dysphagia was identified for comparison. Case notes were reviewed. Results: 44 subjects with oesophageal cancer were identified, 21 before and 23 after guidelines introduced. 8 had 'curative' surgery. Symptom guidelines would have missed 3/23 GP referrals presenting with anaemia, haematemesis and weight loss without dyspepsia. Since guidelines, referrals to endoscopy with dysphagia (excluding outpatient visits) increased from 12 to 13 per month, but the benign:malignant ratio reduced from 6.4: to 4.6:1, suggesting better case selection. Since the guidelines, the mean waiting time to first consultant episode for urgent referrals found to have oesophageol cancer has increased from 19 (range 2-46) to 23 days (3-56), the percentage seen within 14 days dropping from 56 to 46%. The wait to first endoscopy has remained stable (33 days range 2-120). Non-urgent referrals with cancer also showed an increase in wait to first consultant episode from mean 27 (4-50) to 36 days (23-46), the percentage seen within 14 days dropping from 50 to 0%. The wait to first endoscopy has increased from mean 27 (4-50) to 65 (3-107) days. Waiting times have also increased for benign dysphagia. Conclusions: Identifying delays in the patient pathway may improve... [ABSTRACT FROM AUTHOR]

Examines the resurgence of vaccine preventable diseases (VPD) in Australia. Improvement of VPD surveillance; Researches made to inform policy and planning for immunization services; Number of cases of pertussis reported in 1997.