Ulceration of Leg Associated with Therapeutic Femoral Arteriovenous Fistula

We treated a rare case of stasis ulceration of the leg due to surgically induced femoral arteriovenous fistula. The patient is a 24-year-old Japanese man who had poliomyelitis in his infancy and had a sequela of short left lower limb. At ten years of age he underwent surgical creation of a femoral arteriovenous fistula at another hospital to accelerate the bone growth. Although the operation was effective on the growth of the impaired extremity, stasis signs progressed in the left leg and an ulceration developed 14 years after operation. We closed the fistula restoring the arterial and venous continuities, which was followed by a rapid healing of the ulcer

Simulating the carbon balance of a temperate larch forest under various meteorological conditions

<p>Abstract</p> <p>Background</p> <p>Changes in the timing of phenological events may cause the annual carbon budget of deciduous forests to change. Therefore, one should take such events into account when evaluating the effects of global warming on deciduous forests. In this article, we report on the results of numerical experiments done with a model that includes a phenological module simulating the timing of bud burst and other phenological events and estimating maximum leaf area index.</p> <p>Results</p> <p>This study suggests that the negative effects of warming on tree productivity (net primary production) outweigh the positive effects of a prolonged growing season. An increase in air temperature by 3°C (5°C) reduces cumulative net primary production by 21.3% (34.2%). Similarly, cumulative net ecosystem production (the difference between cumulative net primary production and heterotrophic respiration) decreases by 43.5% (64.5%) when temperatures are increased by 3°C (5°C). However, the positive effects of CO₂enrichment (2 × CO₂) outweigh the negative effects of warming (<5°C).</p> <p>Conclusion</p> <p>Although the model was calibrated and validated for a specific forest ecosystem, the implications of the study may be extrapolated to deciduous forests in cool-temperate zones. These forests share common features, and it can be conjectured that carbon stocks would increase in such forests in the face of doubled CO₂and increased temperatures as long as the increase in temperature does not exceed 5°C.</p