Optical modeling of ocean waters: Is the case 1 - case 2 classification still useful?

…two extreme cases can be identified and separated. Case 1 is that of a concentration of phytoplankton high compared to other particles…. In contrast, the inorganic particles are dominant in case 2.… In both cases dissolved yellow substance is present in variable amounts.… An ideal case 1 would be a pure culture of phytoplankton and an ideal case 2 a suspension of nonliving material with a zero concentration of pigments. Morel and Prieur emphasized that these ideal cases are not encountered in nature, and they suggested the use of high or low values of the ratio of pigment concentration to scattering coefficient as a basis for discriminating between Case 1 and Case 2 waters. Although no specific values of this ratio were proposed to serve as criteria for classification, their example data suggested that the ratio of chlorophyll a concentration (in mg m-3) to the scattering coefficient at 550 nm (in m-1) in Case 1 waters is greater than 1 and in Case 2 waters is less than 1. Importantly, however, Morel and Prieur also showed data classified as “intermediate waters” with the ratio between about 1 and 2.2. Although the original definition from 1977 did not imply a binary classification, the practice of most investigators in the following years clearly evolved toward a bipartite analysis

Efficacy of cognitive remediation on activities of daily living in individuals with mild cognitive impairment or early-stage dementia : a systematic review and meta-analysis

Introduction: Instrumental activities of daily living are essential for ageing well and independent living. Little is known about the effectiveness of cognitive remediation on instrumental activities of daily living performance for individuals with mild cognitive impairment or early-stage dementia. The objective of this study was to evaluate the immediate and long-term carryover effects of cognitive remediation on improving or maintaining instrumental activities of daily living performance in older adults with mild cognitive impairment and early-stage dementia. Methods: Randomized controlled trials published from 2009 to 2022 were identified in OvidSP versions of MEDLINE and Embase, EBSCO versions of CINAHL and PsycINFO, and the Cochrane Central Register of Controlled Trials. A narrative synthesis of the findings was reported on the outcomes of the included studies. Relevant data was extracted and analysed using R software’s ‘metafor’ package with a random effect model with 95% CI. Results: Thirteen studies, totalling 1414 participants, were identified in the narrative analysis. The results of meta-analysis, inclusive of 11 studies, showed that cognitive remediation elicited a significant improvement in the instrumental activities of daily living performance (SMD: 0.17, 95% CI 0.03–0.31). There was insufficient evidence of any lasting effect. Discussion: Cognitive remediation is effective in improving instrumental activities of daily living performance immediately post-intervention in older adults with mild cognitive impairment and early-stage dementia. It appears that individualized interventions with a short duration, such as 10 hours, might be beneficial. Systematic review registration: PROSPERO CRD4201604236

Impact of Atmospheric Correction on Classification and Quantification of Seagrass Density from WorldView-2 Imagery

Mapping the seagrass distribution and density in the underwater landscape can improve global Blue Carbon estimates. However, atmospheric absorption and scattering introduce errors in space-based sensors’ retrieval of sea surface reflectance, affecting seagrass presence, density, and above-ground carbon (AGCseagrass) estimates. This study assessed atmospheric correction’s impact on mapping seagrass using WorldView-2 satellite imagery from Saint Joseph Bay, Saint George Sound, and Keaton Beach in Florida, USA. Coincident in situ measurements of water-leaving radiance (Lw), optical properties, and seagrass leaf area index (LAI) were collected. Seagrass classification and the retrieval of LAI were compared after empirical line height (ELH) and dark-object subtraction (DOS) methods were used for atmospheric correction. DOS left residual brightness in the blue and green bands but had minimal impact on the seagrass classification accuracy. However, the brighter reflectance values reduced LAI retrievals by up to 50% compared to ELH-corrected images and ground-based observations. This study offers a potential correction for LAI underestimation due to incomplete atmospheric correction, enhancing the retrieval of seagrass density and above-ground Blue Carbon from WorldView-2 imagery without in situ observations for accurate atmospheric interference correction

Effectiveness of action observation and motor imagery on relearning upper extremity function after stroke : a systematic review and meta-analysis

The effectiveness of action observation (AO) and motor imagery (MI) in high-quality studies with less risk of bias is rarely reported together. This systematic review evaluates the effectiveness of AO and MI on improving upper extremity function among people after stroke by combining evidence of studies with high methodological quality. Randomised controlled trials, with a score of 6 or above in the PEDro Scale, that examined the effects of AO or MI for people with stroke were selected. A narrative analysis and meta-analysis were conducted using the PRISMA guidelines. Ten randomised controlled trials from 11 articles met the inclusion criteria. The results of meta-analysis showed that AO had a small to moderate statistically significant effect on improving upper extremity motor function (standardized mean difference, SMD=0.34; confidence interval, CI=0.08, 0.59; P=0.35; I2=0.00%) and no significant effect on MI (SMD=0.08; CI=-0.26, 0.42; P=0.65; I2=0.00%) when compared with the control intervention. Evidence was found in support of AO and it is recommended for people with acute or sub-acute stroke

Detection of Seagrass Scars Using Sparse Coding and Morphological Filter

We present a two-step algorithm for the detection of seafloor propeller seagrass scars in shallow water using panchromatic images. The first step is to classify image pixels into scar and non-scar categories based on a sparse coding algorithm. The first step produces an initial scar map in which false positive scar pixels may be present. In the second step, local orientation of each detected scar pixel is computed using the morphological directional profile, which is defined as outputs of a directional filter with a varying orientation parameter. The profile is then utilized to eliminate false positives and generate the final scar detection map. We applied the algorithm to a panchromatic image captured at the Deckle Beach, Florida using the WorldView2 orbiting satellite. Our results show that the proposed method can achieve \u3e90% accuracy on the detection of seagrass scars

Black Phosphorus with Near-Superhydrophic Properties and Long-Term Stability in Aqueous Media

Black phosphorus is a two-dimensional material that has potential applications in energy storage, high frequency electronics and sensing, yet it suffers from instability in oxygenated and/or aqueous systems. Here we present the use of a polymeric stabilizer which prevents the degradation of nearly 68% of the material in aqueous media over the course of ca. 1 month

Intercomparison of shallow water bathymetry, hydro-optics, and benthos mapping techniques in Australian and Caribbean coastal environments

Science, resource management, and defense need algorithms capable of using airborne or satellite imagery to accurately map bathymetry, water quality, and substrate composition in optically shallow waters. Although a variety of inversion algorithms are available, there has been limited assessment of performance and no work has been published comparing their accuracy and efficiency. This paper compares the absolute and relative accuracies and computational efficiencies of one empirical and five radiative-transfer-based published approaches applied to coastal sites at Lee Stocking Island in the Bahamas and Moreton Bay in eastern Australia. These sites have published airborne hyperspectral data and field data. The assessment showed that (1) radiative-transfer-based methods were more accurate than the empirical approach for bathymetric retrieval, and the accuracies and processing times were inversely related to the complexity of the models used; (2) all inversion methods provided moderately accurate retrievals of bathymetry, water column inherent optical properties, and benthic reflectance in waters less than 13 m deep with homogeneous to heterogeneous benthic/substrate covers; (3) slightly higher accuracy retrievals were obtained from locally parameterized methods; and (4) no method compared here can be considered optimal for all situations. The results provide a guide to the conditions where each approach may be used (available image and field data and processing capability). A re-analysis of these same or additional sites with satellite hyperspectral data with lower spatial and radiometric resolution, but higher temporal resolution would be instructive to establish guidelines for repeatable regional to global scale shallow water mapping approaches