785 research outputs found
Paleozoic - Geology of the Mt. Pawtuckaway Area
New England Intercollegiate Geological Conference: Southeastern New Hampshire, October 13, and 14, 1956: D - - Pawtuckaway Are
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Expanding or diluting Human Rights? The proliferation of United Nations Special Procedures mandates
The United Nations Special Procedures system was described by former UN Secretary General Kofi Annan as “the crown jewel” of the UN Human Rights Machinery. Yet, in recent years, the system has expanded rapidly, driven by states creating new mandates frequently on topics not traditionally viewed as human rights. This article explores the connection between forms of governance and the states voting for and promoting these newer mandates. We explore states’ potential motivations for expanding the system and the impact on international human rights law. This article forms an important part of discussions about Special Procedures and rights proliferation
Association of Manganese Biomarker Concentrations with Blood Pressure and Kidney Parameters among Healthy Adolescents: NHANES 2013–2018
Deficiency or excess exposure to manganese (Mn), an essential mineral, may have potentially adverse health effects. The kidneys are a major organ of Mn site-specific toxicity because of their unique role in filtration, metabolism, and excretion of xenobiotics. We hypothesized that Mn concentrations were associated with poorer blood pressure (BP) and kidney parameters such as estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), and albumin creatinine ratio (ACR). We conducted a cross-sectional analysis of 1931 healthy U.S. adolescents aged 12–19 years participating in National Health and Nutrition Examination Survey cycles 2013–2014, 2015–2016, and 2017–2018. Blood and urine Mn concentrations were measured using inductively coupled plasma mass spectrometry. Systolic and diastolic BP were calculated as the average of available readings. eGFR was calculated from serum creatinine using the Bedside Schwartz equation. We performed multiple linear regression, adjusting for age, sex, body mass index, race/ethnicity, and poverty income ratio. We observed null relationships between blood Mn concentrations with eGFR, ACR, BUN, and BP. In a subset of 691 participants, we observed that a 10-fold increase in urine Mn was associated with a 16.4 mL/min higher eGFR (95% Confidence Interval: 11.1, 21.7). These exploratory findings should be interpreted cautiously and warrant investigation in longitudinal studies
Field Theory at a Lifshitz Point
We construct the general renormalizable actions for the scalar field and the
gauge field at a Lifshitz point characterized by the dynamical critical
exponent . The Lorentz invariance is broken down in the UV region, but is
recovered in the IR limit. Even though the theories are UV complete, the speed
of light is related to the momentum by which can go to infinity
in the UV limit for . Since the Lorentz invariance is broken down, the
dispersion relation is modified and the time delays in Gamma-Ray bursts can be
easily explained. In addition, we also discuss the thermal dynamics and the
size of causal patch in a FRW universe for the field theory at a Lifshitz
point.Comment: 12 pages; more discussions on the matter with the dynamical critical
exponent z added, version for publication in Phys.Lett.
Volumetric analyses of ablation dimensions in microwave ablation for colorectal liver metastases.
BACKGROUND
In thermal ablation of malignant liver tumors, ablation dimensions remain poorly predictable. This study aimed to investigate factors influencing volumetric ablation dimensions in patients treated with stereotactic microwave ablation (SMWA) for colorectal liver metastases (CRLM).
METHODS
Ablation volumes from CRLM ≤3 cm treated with SMWA within a prospective European multicentre trial were segmented. Correlations between applied ablation energies and resulting effective ablation volumes (EAV) and ablation volume irregularities (AVI) were investigated. A novel measure for AVI, including minimum enclosing and maximum inscribed ellipsoid ablation volumes, and a surrogate parameter for the expansion of ablation energy (EAV per applied energy), was introduced. Potential influences of tumor and patient-specific factors on EAV per applied energy and AVI were analyzed using multivariable mixed-effects models.
RESULTS
A total of 116 ablations from 71 patients were included for analyses. Correlations of EAV or AVI and ablation energy were weak to moderate, with a maximum of 25% of the variability in EAV and 13% in AVI explained by the applied ablation energy. On multivariable analysis, ablation expansion (EAV per applied ablation energy) was influenced mainly by the tumor radius (B = -0.03, [CI -0.04, -0.007]). AVI was significantly larger with higher applied ablation energies (B = 0.002 [CI 0.0007, 0.002]]); liver steatosis, KRAS mutation, subcapsular location or proximity to major blood vessels had no influence.
CONCLUSIONS
This study confirmed that factors beyond the applied ablation energy might affect volumetric ablation dimensions, resulting in poor predictability. Further clinical trials including tissue sampling are needed to relate physical tissue properties to ablation expansion
Clinical application of high frequency jet ventilation in stereotactic liver ablations – a methodological study [version 1; referees: 2 approved]
Background: Computer-assisted navigation during thermal ablation of liver tumours, may help to correct needle placement and improve ablation efficacy in percutaneous, laparoscopic and open interventions. The potential advantage of using high frequency jet-ventilation technique (HFJV) during the procedure is by minimising the amplitude of respiration-related upper-abdominal organs movements. The aim of this clinical methodological trial was to establish whether HFJV would give less ventilatory induced liver movements than conventional ventilation, during stereotactic navigated ablation of liver metastases under open surgery. Methods: Five consecutive patients scheduled for elective, open liver ablation under general propofol and remifentanil anaesthesia were included in the study protocol. During the stereotactic targeting of the tumours, HFJV was chosen for intraoperative lung ventilation. For tracking of liver movement, a rigid marker shield was placed on the liver surface and tracked with an optical position measurement system. A 4D position of the marker shield was measured for HFJV and conventional tidal volume lung ventilation (TV). At each time point the magnitude of liver displacement was calculated as an Euclidean distance between translational component of the marker shield's 3D position and previously estimated centroid of the translational motion. Results: The mean Euclidean liver displacement was 0.80 (0.10) mm for HFJV and 2,90 (1.03) mm for TV with maximum displacement going as far as 12 mm on standard ventilation (p=0.0001). Conclusion: HFJV is a valuable lung ventilation method for patients undergoing stereotactic surgical procedures in general anaesthesia when reduction of organ displacement is crucial
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