192 research outputs found
The Influence of Particle Concentration and Bulk Characteristics on Polarized Oceanographic Lidar Measurements
Oceanographic lidar measurements of the linear depolarization ratio, Ī“, contain information on the bulk characteristics of marine particles that could improve our ability to study ocean biogeochemistry. However, a scarcity of information on the polarized light-scattering properties of marine particles and the lack of a framework for separating single and multiple scattering effects on Ī“ have hindered the development of polarization-based retrievals of bulk particle properties. To address these knowledge gaps, we made single scattering measurements of Ī“ for several compositionally and morphologically distinct marine particle assemblages. We then used a bio-optical model to explore the influence of multiple scattering and particle characteristics on lidar measurements of Ī“ made during an expedition to sample a mesoscale coccolithophore bloom. Laboratory measurements of linear depolarization revealed a complex dependency on particle shape, size, and composition that were consistent with scattering simulations for idealized nonspherical particles. Model results suggested that the variability in Ī“ measured during the field expedition was driven predominantly by shifts in particle concentration rather than their bulk characteristics. However, model estimates of Ī“ improved when calcite particles were represented by a distinct particle class, highlighting the influence of bulk particle properties on Ī“. To advance polarized lidar retrievals of bulk particle properties and to constrain the uncertainty in satellite lidar retrievals of particulate backscattering, these results point to the need for future efforts to characterize the variability of particulate depolarization in the ocean and to quantify the sensitivity of operational ocean lidar systems to multiple scattering
Fighting Global Disparities in Cancer Care:A Surgical Oncology View
Cancer is the second leading cause of death globally after cardiovascular disease. Long-term cancer survival has improved in the Western world due to early detection and the use of effective combined treatment modalities, as well as the development of effective immunotherapy and drug-targeted therapy. Surgery is still the mainstay for most solid tumors; however, low- and middle-income countries are facing an increasing lack of primary surgical care for easily treatable conditions, including breast, colon, and head and neck cancers. In this paper, a surgical oncology view is presented to elaborate how the Western surgical oncologist can take part in the 'surgical fight' against global disparities in cancer care, and a plea is made to strive for structural solutions, such as a partnership in surgical oncology training. The pros and cons of the use of eHealth and mHealth technologies and education programs for schools and the community are discussed as these create an opportunity to reach a large portion of the population in these countries, at low cost and with high impact
Use of single-component wind speed in Rankine-Hugoniot analysis of interplanetary shocks
Melanoma staging: Evidenceābased changes in the American Joint Committee on Cancer eighth edition cancer staging manual
Answer questions and earn CME/CNETo update the melanoma staging system of the American Joint Committee on Cancer (AJCC) a large database was assembled comprising >46,000 patients from 10 centers worldwide with stages I, II, and III melanoma diagnosed since 1998. Based on analyses of this new database, the existing seventh edition AJCC stage IV database, and contemporary clinical trial data, the AJCC Melanoma Expert Panel introduced several important changes to the Tumor, Nodes, Metastasis (TNM) classification and stage grouping criteria. Key changes in the eighth edition AJCC Cancer Staging Manual include: 1) tumor thickness measurements to be recorded to the nearest 0.1 mm, not 0.01 mm; 2) definitions of T1a and T1b are revised (T1a, <0.8 mm without ulceration; T1b, 0.8ā1.0 mm with or without ulceration or <0.8 mm with ulceration), with mitotic rate no longer a T category criterion; 3) pathological (but not clinical) stage IA is revised to include T1b N0 M0 (formerly pathologic stage IB); 4) the N category descriptors āmicroscopicā and āmacroscopicā for regional node metastasis are redefined as āclinically occultā and āclinically apparentā; 5) prognostic stage III groupings are based on N category criteria and T category criteria (ie, primary tumor thickness and ulceration) and increased from 3 to 4 subgroups (stages IIIAāIIID); 6) definitions of N subcategories are revised, with the presence of microsatellites, satellites, or inātransit metastases now categorized as N1c, N2c, or N3c based on the number of tumorāinvolved regional lymph nodes, if any; 7) descriptors are added to each M1 subcategory designation for lactate dehydrogenase (LDH) level (LDH elevation no longer upstages to M1c); and 8) a new M1d designation is added for central nervous system metastases. This evidenceābased revision of the AJCC melanoma staging system will guide patient treatment, provide better prognostic estimates, and refine stratification of patients entering clinical trials. CA Cancer J Clin 2017;67:472ā492. Ā© 2017 American Cancer Society.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139981/1/caac21409_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139981/2/caac21409-sup-0001-suppinfo01.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139981/3/caac21409.pd
Rapid climate-driven circulation changes threaten conservation of endangered north atlantic right whales
As climate trends accelerate, ecosystems will be pushed rapidly into new states, reducing the potential efficacy of conservation strategies based on historical patterns. In the Gulf of Maine, climate-driven changes have restructured the ecosystem rapidly over the past decade. Changes in the Atlantic meridional overturning circulation have altered deepwater dynamics, driving warming rates twice as high as the fastest surface rates. This has had implications for the copepod Calanus finmarchicus, a critical food supply for the endangered North Atlantic right whale (Eubalaena glacialis). The oceanographic changes have driven a deviation in the seasonal foraging patterns of E. glacialis upon which conservation strategies depend, making the whales more vulnerable to ship strikes and gear entanglements. The effects of rapid climate-driven changes on a species at risk undermine current management approaches.publishedVersio
Stress and Burnout Among Surgical Oncologists: A Call for Personal Wellness and a Supportive Workplace Environment
Health profiles of 996 melanoma survivors: the M. D. Anderson experience
BACKGROUND: The incidence and survival of melanoma are increasing, but little is known about its long-term health effects in adult survivors. METHODS: A health survey was available from 996 melanoma survivors (577 treated with surgery alone, and 391 with combined treatments). Their medical/physiologic and psychosocial responses were analyzed and compared with those of the survivors from other cancers. RESULTS: The melanoma survivors were 44.8 Ā± 12.8 years of age at diagnosis (significantly younger than the survivors of other cancers) and 63.7 Ā± 12.8 years at survey. Melanoma survivors were less likely to report that cancer had affected their health than survivors of other cancers (15.8% vs. 34.9%). The 577 individuals treated with surgery alone reported arthritis/osteoporosis, cataracts, and heart problems most frequently (less often than survivors of other cancers). The 391 individuals who had undergone combined treatments reported circulation problems and kidney problems generally as often as survivors of other cancers. Health problems were not associated with number of decades since diagnosis but with age at diagnosis, treatment modality, and family relationships. CONCLUSION: We present information from a large cohort of long-term survivors of melanoma. As a group, they were less likely to report that cancer had affected their overall health than survivors of other cancers; a number of disease related and psychosocial factors appear to influence their health profiles
Achievement of therapeutic antibiotic exposures using Bayesian dosing software in critically unwell children and adults with sepsis
PURPOSE: Early recognition and effective treatment of sepsis improves outcomes in critically ill patients. However, antibiotic exposures are frequently suboptimal in the intensive care unit (ICU) setting. We describe the feasibility of the Bayesian dosing software Individually Designed Optimum Dosing Strategies (ID-ODSā¢), to reduce time to effective antibiotic exposure in children and adults with sepsis in ICU.
METHODS: A multi-centre prospective, non-randomised interventional trial in three adult ICUs and one paediatric ICU. In a pre-intervention Phase 1, we measured the time to target antibiotic exposure in participants. In Phase 2, antibiotic dosing recommendations were made using ID-ODSā¢, and time to target antibiotic concentrations were compared to patients in Phase 1 (a pre-post-design).
RESULTS: 175 antibiotic courses (Phase 1ā=ā123, Phase 2ā=ā52) were analysed from 156 participants. Across all patients, there was no difference in the time to achieve target exposures (8.7Ā h vs 14.3Ā h in Phase 1 and Phase 2, respectively, pā=ā0.45). Sixty-one courses in 54 participants failed to achieve target exposures within 24Ā h of antibiotic commencement (nā=ā36 in Phase 1, nā=ā18 in Phase 2). In these participants, ID-ODSā¢ was associated with a reduction in time to target antibiotic exposure (96 vs 36.4Ā h in Phase 1 and Phase 2, respectively, pā<ā0.01). These patients were less likely to exhibit subtherapeutic antibiotic exposures at 96Ā h (hazard ratio (HR) 0.02, 95% confidence interval (CI) 0.01-0.05, pā<ā0.01). There was no difference observed in in-hospital mortality.
CONCLUSIONS: Dosing software may reduce the time to achieve target antibiotic exposures. It should be evaluated further in trials to establish its impact on clinical outcomes
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