Seasonal Dynamics of Photosynthetic Picoeukaryotes in a Monsoon-Influenced Tropical Bay: a Flow Cytometric and Chemotaxonomic Approach.

The composition and ecology of photosynthetic picoeukaryotes (PPE) are essential for understanding microbial food web functioning. We hypothesize that the simultaneous use of flow cytometry (FCM) and high-performance liquid chromatography (HPLC) tools will aid in discerning the dominant PPE groups contributing to abundance and biomass under prevailing environmental conditions. The PPE seasonal community abundance and pigment biomass were investigated from a southwest monsoon-influenced tropical bay from June 2015 to May 2016. A size-fractionated (<3 µm) approach using FCM and HPLC revealed five and six PPE groups, respectively. Picocryptophytes dominated the PPE biomass under varied environmental conditions, whereas picodiatoms contributed substantially, being abundant under turbulent, low-temperature, nutrient (NO3-, SiO44-)-enriched conditions. The picochlorophytes dominated the community numerically. The relatively higher abundance and biomass of picoprasinophytes and a positive correlation with NO3- and NH4+ imply proliferation under higher nutrient concentrations. The least contributors to biomass were dinoflagellates and picoprymnesiophytes. The relatively larger cell size of picocryptophytes and picodiatoms resulted in higher cumulative biomass, signifying their role in the microbial food web. Our study proposes incorporation of additional indicator pigments in algorithms used to estimate coastal picophytoplankton contribution to total phytoplankton biomass to avoid discrepancies.

Dark survival in biofilm-forming microalgae: potential for colonizing benthic ecosystems.

The biofilm-forming microalgae are known to experience periods of continuous darkness (upto several days), in addition to the natural day-night cycle, especially in the intertidal sediment regions (when transported to deeper sediments) and the ships' ballast water tanks (during voyages). However, the information on community and physiological responses to different periods of darkness is limited. Here, the survival capability of biofilm-forming microalgae to varying periods of darkness (7-35 days) and the growth patterns upon resumption of normal 12 h light:dark photocycle has been addressed through simulation experiments. Diatoms dominated the seawater biofilms, but the dark survival period varied and was species-specific. Of the 25 diatoms, only Amphora, potential toxin producer, followed by Navicula remained viable and photosynthetically healthy under darkness without undergoing asexual reproduction. Both diatoms are essential contributors to fouling and microphytobenthic community. Upon re-exposure of dark-adapted biofilms to 12 h light:dark photocycle, the improvement in photosynthetic efficiency and resumption of growth via asexual-reproduction was observed. However, the lag-phase duration increased with a long dark history. Nevertheless, eurytolerant nature and high dark survival capability (with its quick response to light) of Amphora and Navicula indicated that they have the potential to colonize benthic-ecosystems thus impacting the benthic and fouling community.

A grounded theory study to identify caregiving phases and support needs across the Alzheimer's disease trajectory.

PURPOSE: Caregivers of individuals with Alzheimer's disease require support across the full disease trajectory. The aim of this study was to develop a conceptual framework of caregiving phases across the Alzheimer's disease and caregiving trajectories and the corresponding caregiver support needs. MATERIALS AND METHODS: Constructivist grounded theory informed data collection and analysis. 40 spousal (n = 20) and adult children (n = 20) caregivers were interviewed. Recruitment was completed when theoretical saturation was achieved. Member-checking interviews occurred with 10 participants. RESULTS: Participants described five phases of caregiving related to their responsibilities to support people with Alzheimer's disease including monitoring initial symptoms, navigating their diagnosis, assisting with instrumental activities of daily living, assisting with basic activities of daily living, and preparing for the future. Support (i.e., informational, emotional, instrumental, and appraisal) needs were often specific to the phase of care. For example, during the initial symptoms phase, caregivers reported needing information to assist them to distinguish normal aging from cognitive impairment. In contrast, during the preparing for the future phase, caregivers emphasized support for accessing institutional long term-care placement. CONCLUSIONS: Findings highlight caregiver-identified phases of caregiving and corresponding support needs across the Alzheimer's disease trajectory. Findings can inform the development, evaluation and implementation of programs and services to meet caregivers' changing needs across the disease trajectory.IMPLICATIONS FOR REHABILITATIONCaregivers for individuals with Alzheimer's disease can experience distinct caregiving phases across the disease trajectory with corresponding support needs.Rehabilitation clinicians can use these findings to help caregivers navigate available supports at appropriate times to ensure that their needs are addressed across the disease trajectory.Occupational therapists and other rehabilitation professionals can enable caregivers with timely education and support as they progress across the disease trajectory.

Somatosensory Plasticity in Hemiplegic Cerebral Palsy Following Constraint Induced Movement Therapy.

BACKGROUND: Children with hemiplegic cerebral palsy (HCP) experience upper limb somatosensory and motor deficits. Although constraint-induced movement therapy (CIMT) improves motor function, its impact on somatosensory function remains underinvestigated. OBJECTIVE: The objective of this study was to evaluate somatosensory perception and related brain responses in children with HCP, before and after a somatosensory enhanced CIMT protocol, as measured using clinical sensory and motor assessments and magnetoencephalography. METHODS: Children with HCP attended a somatosensory enhanced CIMT camp. Clinical somatosensory (tactile registration, 2-point discrimination, stereognosis, proprioception, kinesthesia) and motor outcomes (Quality of Upper Extremity Skills [QUEST] Total/Grasp, Jebsen-Taylor Hand Function Test, grip strength, Assisting Hand Assessment), as well as latency and amplitude of magnetoencephalography somatosensory evoked fields (SEF), were assessed before and after the CIMT camp with paired sample t-tests or Wilcoxon signed-rank tests. RESULTS: Twelve children with HCP (mean age: 7.5 years, standard deviation: 2.4) participated. Significant improvements in tactile registration for the affected (hemiplegic) hand (Z = 2.39, P = 0.02) were observed in addition to statistically and clinically significant improvements in QUEST total (t = 3.24, P = 0.007), QUEST grasp (t = 3.24, P = 0.007), Assisting Hand Assessment (Z = 2.25, P = 0.03), and Jebsen-Taylor Hand Function Test (t = -2.62, P = 0.03). A significant increase in the SEF peak amplitude was also found in the affected hand 100 ms after stimulus onset (t = -2.22, P = 0.04). CONCLUSIONS: Improvements in somatosensory clinical function and neural processing in the affected primary somatosensory cortex in children with HCP were observed after a somatosensory enhanced CIMT program. Further investigation is warranted to continue to evaluate the effectiveness of a sensory enhanced CIMT program in larger samples and controlled study designs.