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Ocean bottom pressure (OBP) changes are caused by a redistribution of the ocean's internal mass that are driven by atmospheric circulation, a change in the mass entering or leaving the ocean, and/or a change in the integrated atmospheric mass over the ocean areas. The only previous global analysis investigating the magnitude of OBP surface displacements used older OBP data sets (van Dam et al. in J Geophys Res 129:507-517, ). Since then significant improvements in meteorological forcing models used to predict OBP have been made, augmented by observations from satellite altimetry and expendable bathythermograph profiles. Using more recent OBP estimates from the Estimating the Circulation and Climate of the Ocean (ECCO) project, we reassess the amplitude of the predicted effect of OBP on the height coordinate time series from a global distribution of GPS stations. OBP-predicted loading effects display an RMS scatter in the height of between 0.2 and 3.7 mm, larger than previously reported but still much smaller (by a factor of 2) than the scatter observed due to atmospheric pressure loading. Given the improvement in GPS hardware and data analysis techniques, the OBP signal is similar to the precision of weekly GPS height coordinates. We estimate the effect of OBP on GPS height coordinate time series using the MIT reprocessed solution, mi1. When we compare the predicted OBP height time series with mi1, we find that the scatter is reduced over all stations by 0.1 mm on average with reductions as high as 0.7 mm at some stations. More importantly we are able to reduce the scatter on 65 % of the stations investigated. The annual component of the OBP signal is responsible for 80 % of the reduction in scatter on average. We find that stations located close to semi-enclosed bays or seas are affected by OBP loading to a greater extent than other stations. [ABSTRACT FROM AUTHOR]

This double-blind, parallel group study compared a 2-week course of terbinafine 250 mg/day with a 4-week course of itraconazole 100 mg/day. A total of 190 patients were enrolled, of whom 129 were evaluable for efficacy. At week 8, 69% of patients treated with terbinafine were classified as effectively treated (mycological cure, and clinical assessment total score ⩽ 2) vs. 67% in the itraconazole group. At week 16. however, the rating for effective treatment increased to 71% of the terbinafine group, but decreased to 55% of the itraconazole group. This difference was of borderline statistical significance (P = 0.06). The results of this study demonstrate that both drugs can be used safely, and that 2 weeks' treatment with terbinafine 250 mg daily is as effective as 4 weeks' treatment with itraconazole l00 mg daily, but with fewer long-term relapses. [ABSTRACT FROM AUTHOR]

Ice dynamic change is the primary cause of mass loss from the Antarctic Ice Sheet, thus it is important to understand the processes driving ice-ocean interactions and the timescale on which major change can occur. Here we use satellite observations to measure a rapid increase in speed and collapse of the ice shelf fronting Cadman Glacier in the absence of surface meltwater ponding. Between November 2018 and December 2019 ice speed increased by 94 ± 4% (1.47 ± 0.6 km/yr), ice discharge increased by 0.52 ± 0.21 Gt/yr, and the calving front retreated by 8 km with dynamic thinning on grounded ice of 20.1 ± 2.6 m/yr. This change was concurrent with a positive temperature anomaly in the upper ocean, where a 400 m deep channel allowed warm water to reach Cadman Glacier driving the dynamic activation, while neighbouring Funk and Lever Glaciers were protected by bathymetric sills across their fjords. Our results show that forcing by warm ocean water can cause the rapid onset of dynamic imbalance and increased ice discharge from glaciers on the Antarctic Peninsula, highlighting the region's sensitivity to future climate variability., (© 2023. The Author(s).)

Antarctic ice shelves moderate the contribution of the Antarctic Ice Sheet to global sea level rise; however, ice shelf health remains poorly constrained. Here, we present the annual mass budget of all Antarctic ice shelves from 1997 to 2021. Out of 162 ice shelves, 71 lost mass, 29 gained mass, and 62 did not change mass significantly. Of the shelves that lost mass, 68 had statistically significant negative mass trends, 48 lost more than 30% of their initial mass, and basal melting was the dominant contributor to that mass loss at a majority (68%). At many ice shelves, mass losses due to basal melting or iceberg calving were significantly positively correlated with grounding line discharge anomalies; however, the strength and form of this relationship varied substantially between ice shelves. Our results illustrate the utility of partitioning high-resolution ice shelf mass balance observations into its components to quantify the contributors to ice shelf mass change and the response of grounded ice.

The Getz region of West Antarctica is losing ice at an increasing rate; however, the forcing mechanisms remain unclear. Here we use satellite observations and an ice sheet model to measure the change in ice speed and mass balance of the drainage basin over the last 25-years. Our results show a mean increase in speed of 23.8 % between 1994 and 2018, with three glaciers accelerating by over 44 %. Speedup across the Getz basin is linear, with speedup and thinning directly correlated confirming the presence of dynamic imbalance. Since 1994, 315 Gt of ice has been lost contributing 0.9 ± 0.6 mm global mean sea level, with increased loss since 2010 caused by a snowfall reduction. Overall, dynamic imbalance accounts for two thirds of the mass loss from this region of West Antarctica over the past 25-years, with a longer-term response to ocean forcing the likely driving mechanism.

Pine Island Glacier and Thwaites Glacier in the Amundsen Sea Embayment are among the fastest changing outlet glaciers in West Antarctica with large consequences for global sea level. Yet, assessing how much and how fast both glaciers will weaken if these changes continue remains a major uncertainty as many of the processes that control their ice shelf weakening and grounding line retreat are not well understood. Here, we combine multisource satellite imagery with modeling to uncover the rapid development of damage areas in the shear zones of Pine Island and Thwaites ice shelves. These damage areas consist of highly crevassed areas and open fractures and are first signs that the shear zones of both ice shelves have structurally weakened over the past decade. Idealized model results reveal moreover that the damage initiates a feedback process where initial ice shelf weakening triggers the development of damage in their shear zones, which results in further speedup, shearing, and weakening, hence promoting additional damage development. This damage feedback potentially preconditions these ice shelves for disintegration and enhances grounding line retreat. The results of this study suggest that damage feedback processes are key to future ice shelf stability, grounding line retreat, and sea level contributions from Antarctica. Moreover, they underline the need for incorporating these feedback processes, which are currently not accounted for in most ice sheet models, to improve sea level rise projections., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Background: Current treatment modalities for chronic leg ulcers are time consuming, expensive, and only moderately successful. Recent data suggest that creating a subatmospheric pressure by vacuum-assisted closure (V.A.C., KCI Concepts, San Antonio, Texas) therapy supports the wound healing process., Methods: The efficacy of vacuum-assisted closure in the treatment of chronic leg ulcers was prospectively studied in a randomized controlled trial in which 60 hospitalized patients with chronic leg ulcers were randomly assigned to either treatment by V.A.C. or therapy with conventional wound care techniques. The primary outcome measure was the time to complete healing (days). Statistical analysis was performed on the intention-to-treat basis., Results: The median time to complete healing was 29 days (95% confidence interval [CI], 25.5 to 32.5) in the V.A.C. group compared with 45 days (95% CI, 36.2 to 53.8) in the control group (P = .0001). Further, wound bed preparation during V.A.C. therapy was also significantly shorter at 7 days (95% CI 5.7 to 8.3) than during conventional wound care at 17 days (95% CI, 10 to 24, P = .005). The costs of conventional wound care were higher than those of V.A.C. Both groups showed a significant increase in quality of life at the end of therapy and a significant decrease in pain scores at the end of follow-up., Conclusions: V.A.C. therapy should be considered as the treatment of choice for chronic leg ulcers owing to its significant advantages in the time to complete healing and wound bed preparation time compared with conventional wound care. Particularly during the preparation stage, V.A.C. therapy appears to be superior to conventional wound care techniques.

A 53-yr-old man, known to have had AIDS for 6 months, developed the clinical signs and symptoms of porphyria cutanea tarda (PCT) preceding deterioration of his illness. Urinary porphyrin analysis confirmed the diagnosis of PCT. At the time the cutaneous blistering and scars developed, he was taking zidovudine and fluconazole. Reviewing the literature suggested that association of the two disorders is not purely coincidental. Anaemia, due to chronic immune activation and therapeutic options in the light of AIDS, could play an important role in the development of PCT. We recommend analysing the urine for porphyrins in HIV-positive patients who have chronic photosensitivity of the skin.

Terbinafine is an allylamine antifungal compound shown to be effective in the oral treatment of onychomycosis. Because of the fungicidal activity of the drug, a shorter duration of treatment, compared with the currently used oral treatment modalities, can be expected in onychomycosis of the toenail. In the present randomized study, the efficacy of oral terbinafine treatment (250 mg/day) was assessed for periods of 6, 12, and 24 weeks. All patients were followed for up to 48 weeks after starting treatment. Of the 120 patients with toenail onychomycosis who entered the study, 98 were evaluable for efficacy. The involvement of the toenails was assessed both clinically and mycologically throughout the study. Evaluation at 24 weeks showed that complete cure of toenail onychomycosis was achieved in 67% of patients treated for 6 weeks, 82% treated for 12 weeks, and 85% treated for 24 weeks. At the end of a further 24 weeks of follow-up, cure rates were 40%, 71% and 79%, respectively. The adverse effects of terbinafine were mostly mild-to-moderate gastrointestinal symptoms. Three patients discontinued treatment because of side-effects. In conclusion, oral treatment with terbinafine is effective and generally well tolerated in patients with onychomycosis. Our results demonstrate that, for toenail onychomycosis, a treatment period of 12 weeks is sufficient.

Seventy-three patients with psoriasis were treated in an open multicenter study with betamethasone dipropionate 0.05 percent cream (twice daily application for four days) alternated with the cream base (twice daily application for three days). The therapeutic response at the end of the treatment period of three weeks was very satisfactory: 39 patients had marked improvement or recovery, 16 patients had moderate improvement, and 14 patients had slight improvement. These results did not differ from those of a study on continuous treatment with betamethasone dipropionate cream in the treatment of psoriasis. Side effects (folliculitis) were only noted in one patient.

Between 1978 and 1982 an experiment on group treatment for and by psoriasis sufferers was conducted, based on a pyramid of previous investigations since 1968. Each group was facilitated by a duo consisting of a fellow sufferer and a physician, both having trained together. The subjects practiced the procedure described, directed toward self-care and mutual aid facilitated and supported by the duo, in a series of ten 2-hour weekly sessions. A pretest/posttest control group design was used. Comparing the results of the quantitative analysis of the experimental groups with those of the control groups, the experimental groups showed significant change. The results of the qualitative analysis showed that decrease of anxiety correlated with mastering of the skills involved. The key element affecting outcome was the balance in cooperation within the duo, the expertise of the patient lying in his personal experience of the condition, and the expertise of the physician in his knowledge and skills. One of the method's main characteristics was the intrinsic complementarity of the duo partners.

Group treatment for and by psoriasis patients was the subject of a trial. For 12 sessions over a period of 3 months, a fellow sufferer as co-helper cooperated with a professional specialist as co-worker according to the so-called duo formula. When the results were compared with those in a control group, the patients showed a change in the dimensions examined, as well as in their illness behaviour and insight into the value of problem-solving in groups. Therefore, it is recommended that dermatologist/co-helper teams be instructed for group treatment of chronic skin diseases, because this method stimulates self-activity in patients.