Calibration of ultrasound scanners for surface impedance measurement

The primary objective of this research was to investigate the feasibility of calibrating ultrasound scanners to measure surface impedance from reflection data. The method proposed uses calibration curves from known impedance interfaces. This plot, or calibration curve, may then be used, with interpolation, to relate measured grey level to impedance for the characterization of tissue specimens with unknown properties. This approach can be used independent of different medical ultrasound scanner systems to solve for reproducible tissue impedance values without offline data processing and complicated custom electronics. Two medical ultrasound machines from different manufacturers were used in the experiment; a 30 MHz and a 7.5 MHz machine. The calibration curves for each machine were produced by imaging the interfaces of a vegetable oil floating over varying salt solutions. To test the method, porcine liver, kidney, and spleen acoustical impedances were determined by relating measured grey levels to reflection coefficients using calibration curves and then inverting the reflection coefficients to obtain impedance values. The 30 MHz ultrasound machine’s calculated tissue impedances for liver, kidney, and spleen were 1.476 ± 0.020, 1.486 ± 0.020, 1.471 ± 0.020 MRayles respectively. The 7.5 MHz machine’s tissue impedances were 1.467 ± 0.088, 1.507 ± 0.088, and 1.457 ± 0.088 MRayles respectively for liver, kidney and spleen. The differences between the two machines are 0.61%, 1.41%, and 0.95% for the impedance of liver, kidney, and spleen tissue, respectively. If the grey level is solely used to characterize the tissue, then the differences are 45.9%, 40.3%, and 39.1% for liver, kidney, and spleen between the two machines. The results support the hypothesis that tissue impedance can be determined using calibration curves and be consistent between multiple machines

ConSLAM: Periodically Collected Real-World Construction Dataset for SLAM

International audienc

Citostatsko i protuupalno djelovanje polisaharida biljke Ganoderma lucidum

In this study, polysaccharides were isolated from Ganoderma lucidum (Polyporaceae) and their antitumor and anti-inflammatory activities were investigated using in vivo models. Potential antitumor activity was shown by G. lucidum polysaccharides (GLP) against solid tumor induced by Ehrlich’s ascites carcinoma cells. GLP at 100 mg kg–1 body mass showed 80.8 and 77.6 % reduction in tumour volume and tumour mass, respectively, when administered 24 h after tumour implantation. Again, GLP at the same dose but when administered prior to tumour inoculation, showed 79.5 and 81.2 % inhibition of tumour volume and tumour mass, respectively. GLP showed significant dose-dependent activity in carrageenean-induced (acute) and formalin-induced (chronic) inflammation assays. At 100 mg kg–1, GLP exhibited 57.6 and 58.2 % inhibition in carrageenean-induced and formalin-induced assays, respectively.U radu je ispitano in vivo citostatsko i protuupalno djelovanje polisaharida (GLP) izoliranih iz biljke Ganoderma lucidum (Polyporaceae). Ispitivani polisaharidi pokazali su potencijalno antitumorsko djelovanje na Ehrlichov ascitesni tumor. GLP su u dozi od 100 mg kg1 tjelesne mase inhibirali volumen tumora za 80,8, a njegovu masu za 77,6 %, kada su primijenjeni 24 h nakon implantacije tumora. Ako se GLP daju u istoj dozi prije inokulacije tumora, inhibiraju volumen tumora za 79,5, a njegovu masu za 81,2 %. GLP pokazuju značajno, o dozi ovisno, protuupalno djelovanje u karagenan testu (akutna upala) i formalin testu (kronična upala). U dozi od 100 mg kg1, GLP inhibiraju upalne procese za 57,6 odnosno 58,2 % u testu s karagenanom, odnosno formalinom

Citostatsko i protuupalno djelovanje polisaharida biljke Ganoderma lucidum

In this study, polysaccharides were isolated from Ganoderma lucidum (Polyporaceae) and their antitumor and anti-inflammatory activities were investigated using in vivo models. Potential antitumor activity was shown by G. lucidum polysaccharides (GLP) against solid tumor induced by Ehrlich’s ascites carcinoma cells. GLP at 100 mg kg–1 body mass showed 80.8 and 77.6 % reduction in tumour volume and tumour mass, respectively, when administered 24 h after tumour implantation. Again, GLP at the same dose but when administered prior to tumour inoculation, showed 79.5 and 81.2 % inhibition of tumour volume and tumour mass, respectively. GLP showed significant dose-dependent activity in carrageenean-induced (acute) and formalin-induced (chronic) inflammation assays. At 100 mg kg–1, GLP exhibited 57.6 and 58.2 % inhibition in carrageenean-induced and formalin-induced assays, respectively.U radu je ispitano in vivo citostatsko i protuupalno djelovanje polisaharida (GLP) izoliranih iz biljke Ganoderma lucidum (Polyporaceae). Ispitivani polisaharidi pokazali su potencijalno antitumorsko djelovanje na Ehrlichov ascitesni tumor. GLP su u dozi od 100 mg kg1 tjelesne mase inhibirali volumen tumora za 80,8, a njegovu masu za 77,6 %, kada su primijenjeni 24 h nakon implantacije tumora. Ako se GLP daju u istoj dozi prije inokulacije tumora, inhibiraju volumen tumora za 79,5, a njegovu masu za 81,2 %. GLP pokazuju značajno, o dozi ovisno, protuupalno djelovanje u karagenan testu (akutna upala) i formalin testu (kronična upala). U dozi od 100 mg kg1, GLP inhibiraju upalne procese za 57,6 odnosno 58,2 % u testu s karagenanom, odnosno formalinom

Historical exclusion, conflict, health systems and Ill-health among tribal communities in India : a synthesis of three studies

The report aims to consolidate key findings across three studies among tribal populations in India; to understand and explain the diverse nature of health inequities along with processes and historical contexts which create, configure and sustain these inequities; it also questions the existing understanding of health equity. The three research partners explored different facets of health inequities among tribal communities from diverse historical and geographic contexts. A detailed sub-section examines the role of the health system in health inequities experienced by the tribal communities

Characteristics of patients in platform C19, a COVID-19 research database combining primary care electronic health record and patient reported information

Background Data to better understand and manage the COVID-19 pandemic is urgently needed. However, there are gaps in information stored within even the best routinely-collected electronic health records (EHR) including test results, remote consultations for suspected COVID-19, shielding, physical activity, mental health, and undiagnosed or untested COVID-19 patients. Observational and Pragmatic Research Institute (OPRI) Singapore and Optimum Patient Care (OPC) UK established Platform C19, a research database combining EHR data and bespoke patient questionnaire. We describe the demographics, clinical characteristics, patient behavior, and impact of the COVID-19 pandemic using data within Platform C19. Methods EHR data from Platform C19 were extracted from 14 practices across UK participating in the OPC COVID-19 Quality Improvement program on a continuous, monthly basis. Starting 7th August 2020, consenting patients aged 18–85 years were invited in waves to fill an online questionnaire. Descriptive statistics were summarized using all data available up to 22nd January 2021. Findings From 129,978 invitees, 31,033 responded. Respondents were predominantly female (59.6%), white (93.5%), and current or ex-smokers (52.6%). Testing for COVID-19 was received by 23.8% of respondents, of which 7.9% received positive results. COVID-19 symptoms lasted ≥4 weeks in 19.5% of COVID-19 positive respondents. Up to 39% respondents reported a negative impact on questions regarding their mental health. Most (67%-76%) respondents with asthma, Chronic Obstructive Pulmonary Disease (COPD), diabetes, heart, or kidney disease reported no change in the condition of their diseases. Interpretation Platform C19 will enable research on key questions relating to COVID-19 pandemic not possible using EHR data alone

Mary's Powers of Imagination

One common response to the knowledge argument is the ability hypothesis. Proponents of the ability hypothesis accept that Mary learns what seeing red is like when she exits her black-and-white room, but they deny that the kind of knowledge she gains is propositional in nature. Rather, she acquires a cluster of abilities that she previously lacked, in particular, the abilities to recognize, remember, and imagine the color red. For proponents of the ability hypothesis, knowing what an experience is like simply consists in the possession of these abilities. Criticisms of the ability hypothesis tend to focus on this last claim. Such critics tend to accept that Mary gains these abilities when she leaves the room, but they deny that such abilities constitute knowledge of what an experience is like. To my mind, however, this critical strategy grants too much. Focusing specifically on imaginative ability, I argue that Mary does not gain this ability when she leaves the room for she already had the ability to imagine red while she was inside it. Moreover, despite what some have thought, the ability hypothesis cannot be easily rescued by recasting it in terms of a more restrictive imaginative ability. My purpose here is not to take sides in the debate about physicalism, i.e., my criticism of the ability hypothesis is not offered in an attempt to defend the anti-physicalist conclusion of the knowledge argument. Rather, my purpose is to redeem the imagination from the misleading picture of it that discussion of the knowledge argument has fostered

Grounding, Analysis, and Russellian Monism

Few these days dispute that the knowledge argument demonstrates an epistemic gap between the physical facts and the facts about experience. It is much more contentious whether that epistemic gap can be used to demonstrate a metaphysical gap of a kind that is inconsistent with physicalism. In this paper I will explore two attempts to block the inference from an epistemic gap to a metaphysical gap – the first from the phenomenal concept strategy, the second from Russellian monism – and suggest how the proponent of the knowledge argument might respond to each of these challenges. In doing so, I will draw on recent discussions of grounding and essence in the metaphysics literature

Atrial Fibrillation Burden and Atrial Shunt Therapy in Heart Failure With Preserved Ejection Fraction

Background: Atrial fibrillation (AF) is a common comorbidity in patients with heart failure with preserved ejection fraction (HFpEF) and in heart failure with mildly reduced ejection fraction (HFmrEF). Objectives: This study sought to describe AF burden and its clinical impact among individuals with HFpEF and HFmrEF who participated in a randomized clinical trial of atrial shunt therapy (REDUCE LAP-HF II [A Study to Evaluate the Corvia Medical, Inc IASD System II to Reduce Elevated Left Atrial Pressure in Patients with Heart Failure]) and to evaluate the effect of atrial shunt therapy on AF burden. Methods: Study investigators characterized AF burden among patients in the REDUCE LAP-HF II trial by using ambulatory cardiac patch monitoring at baseline (median patch wear time, 6 days) and over a 12-month follow-up (median patch wear time, 125 days). The investigators determined the association of baseline AF burden with long-term clinical events and examined the effect of atrial shunt therapy on AF burden over time. Results: Among 367 patients with cardiac monitoring data at baseline and follow-up, 194 (53%) had a history of AF or atrial flutter (AFL), and median baseline AF burden was 0.012% (IQR: 0%-1.3%). After multivariable adjustment, baseline AF burden ≥0.012% was significantly associated with heart failure (HF) events (HR: 2.00; 95% CI: 1.17-3.44; P = 0.01) both with and without a history of AF or AFL (P for interaction = 0.68). Adjustment for left atrial reservoir strain attenuated the baseline AF burden-HF event association (HR: 1.71; 95% CI: 0.93-3.14; P = 0.08). Of the 367 patients, 141 (38%) had patch-detected AF during follow-up without a history of AF or AFL. Atrial shunt therapy did not change AF incidence or burden during follow-up. Conclusions: In HFpEF and HFmrEF, nearly 40% of patients have subclinical AF by 1 year. Baseline AF burden, even at low levels, is associated with HF events. Atrial shunt therapy does not affect AF incidence or burden.</p