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Over the past two decades, with recognition that the ocean's sea-ice cover is neither insensitive to climate change nor a barrier to light and matter, research in sea-ice biogeochemistry has accelerated significantly, bringing together a multi-disciplinary community from a variety of fields. This disciplinary diversity has contributed a wide range of methodological techniques and approaches to sea-ice studies, complicating comparisons of the results and the development of conceptual and numerical models to describe the important biogeochemical processes occurring in sea ice. Almost all chemical elements, compounds, and biogeochemical processes relevant to Earth system science are measured in sea ice, with published methods available for determiningbiomass, pigments, net community production, primary production, bacterial activity, macronutrients, numerous natural and anthropogenic organic compounds, trace elements, reactive and inert gases, sulfur species, the carbon dioxide system parameters, stable isotopes, and water-ice-Atmosphere fluxes of gases, liquids, and solids. For most of these measurements, multiple sampling and processing techniques are available, but to date there has been little intercomparison or intercalibration between methods. In addition, researchers collect different types of ancillary data and document their samples differently, further confounding comparisons between studies. These problems are compounded by the heterogeneity of sea ice, in which even adjacent cores can have dramatically different biogeochemical compositions. We recommend that, in future investigations, researchers design their programs based on nested sampling patterns, collect a core suite of ancillary measurements, and employ a standard approach for sample identification and documentation. In addition, intercalibration exercises are most critically needed for measurements of biomass, primary production, nutrients, dissolved and particulate organic matter (including exopolymers), the CO2 system, air-ice gas fluxes, and aerosol production. We also encourage the development of in situ probes robust enough for long-Term deployment in sea ice, particularly for biological parameters, the CO2 system, and other gases.

Important findings from the second decade of the 21st century on the impact of environmental change on biological processes in the Antarctic were synthesised by 26 international experts. Ten key messages emerged that have stakeholder-relevance and/or a high impact for the scientific community. They address (i) altered biogeochemical cycles, (ii) ocean acidification, (iii) climate change hotspots, (iv) unexpected dynamism in seabed-dwelling populations, (v) spatial range shifts, (vi) adaptation and thermal resilience, (vii) sea ice related biological fluctuations, (viii) pollution, (ix) endangered terrestrial endemism and (x) the discovery of unknown habitats. Most Antarctic biotas are exposed to multiple stresses and considered vulnerable to environmental change due to narrow tolerance ranges, rapid change, projected circumpolar impacts, low potential for timely genetic adaptation, and migration barriers. Important ecosystem functions, such as primary production and energy transfer between trophic levels, have already changed, and biodiversity patterns have shifted. A confidence assessment of the degree of 'scientific understanding' revealed an intermediate level for most of the more detailed sub-messages, indicating that process-oriented research has been successful in the past decade. Additional efforts are necessary, however, to achieve the level of robustness in scientific knowledge that is required to inform protection measures of the unique Antarctic terrestrial and marine ecosystems, and their contributions to global biodiversity and ecosystem services., (© 2020 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

Ice-associated microalgae make a significant seasonal contribution to primary production and biogeochemical cycling in polar regions. However, the distribution of algal cells is driven by strong physicochemical gradients which lead to a degree of microspatial variability in the microbial biomass that is significant, but difficult to quantify. We address this methodological gap by employing a field-deployable hyperspectral scanning and photogrammetric approach to study sea-ice cores. The optical set-up facilitated unsupervised mapping of the vertical and horizontal distribution of phototrophic biomass in sea-ice cores at mm-scale resolution (using chlorophyll a [Chl a] as proxy), and enabled the development of novel spectral indices to be tested against extracted Chl a (R 2  ≤ 0.84). The modelled bio-optical relationships were applied to hyperspectral imagery captured both in situ (using an under-ice sliding platform) and ex situ (on the extracted cores) to quantitatively map Chl a in mg m -2 at high-resolution (≤ 2.4 mm). The optical quantification of Chl a on a per-pixel basis represents a step-change in characterising microspatial variation in the distribution of ice-associated algae. This study highlights the need to increase the resolution at which we monitor under-ice biophysical systems, and the emerging capability of hyperspectral imaging technologies to deliver on this research goal.

Introduction: With rising student debt, identifying ways for students to contain the cost of their education is highly desired. Numerous prerequisite courses are required for admission to a physical therapy program and have been shown to predict success in the National Physical Therapy Examination (NPTE) following graduation. Identifying how pre-admission courses completed at a 2-year vs 4-year institution impacts student success may allow students to be more selective about where they complete courses, thereby decreasing the amount of debt accumulated prior to entering graduate education. This study was designed to investigate the relationship between type of institution where students completed prerequisite coursework and subsequent NPTE scores and the related financial ramifications., Methods: Participants (n=309) included students who graduated from two CAPTE-accredited DPT programs at private universities in the U.S. Midwest. This retrospective, correlational quantitative study analyzed independent variables that included GRE scores (verbal and quantitative), DPT GPA at the end of the first year, DPT GPA at graduation, undergraduate overall GPA and science GPA, number of credit hours completed at a 2-year institution, and number of prerequisite credit hours completed at a 2-year institution. Pearson correlation, multiple regression, and stepwise regression were utilized for data analysis., Results: Multiple stepwise regression found that first-year DPT GPA alone was the most statistically significant predictor (r=0.591, p<0.001) of outcome on the NPTE, while GRE Quantitative improved the significance of the final predictive equation by 2.2%. Number of community college credit hours and prerequisite hours completed at a community college were not identified by multiple regression as predictors of variance in NPTE scores., Conclusion: With the first-year DPT GPA shown to explain 35% of the variance in NPTE scores, with an additional 2% contributed by GRE Quantitative, our findings can be used by faculty to identify students earlier who may need additional guidance and support. For students, taking prerequisite courses at a community college vs a 4-year institution is a cost-saving alternative found to have no impact on NPTE score.

Background: The purpose was to examine student performance in a clinical setting after an extra-curricular student experiential learning experience., Methods: Ten Certified Strength and Conditioning Specialist (CSCS) Doctor of Physical Therapy students participated in performing strength and conditioning services during the second year of the professional education program. Clinical instructor comments were evaluated from the midterm assessment. Data were collected over 3 years for this study., Results: The main themes that emerged from clinical instructors' comments were that students demonstrated good communication skills, including managing challenging conversations with colleagues, patients, and other professionals; effective interprofessional interactions and teamwork; attention to movement analysis; and empathy when working with a diverse group of patients. The majority of clinical instructors reported that students exceeded expectations for performance., Conclusion: The experiential learning opportunity of performing strength and conditioning training may foster the development of professional and clinical skills, such as interprofessional collaborations and managing challenging conversations with a broad range of individuals, as is required in clinical practice.

The durability of plastics in the marine environment has led to concerns regarding the pervasiveness of this debris in remote polar habitats. Microplastic (MP) enrichment in East Antarctic sea ice was measured in one ice core sampled from coastal land-fast sea ice. The core was processed and filtered material was analyzed using micro Fourier-Transform Infrared (μFTIR) spectroscopy. 96 MP particles were identified, averaging 11.71 particles L -1 . The most common MP polymers (polyethylene, polypropylene, and polyamide) were consistent with those most frequently represented in the majority of marine MP studies. Sea-ice MP concentrations were positively related with chlorophyll a, suggesting living biomass could assist in incorporating MPs in sea ice. Our preliminary results indicate that sea ice has the potential to serve as a reservoir for MP debris in the Southern Ocean, which may have consequences for Southern Ocean food webs and biogeochemistry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Purpose/background: Various methods are available for assessment of static and dynamic postural stability. The primary purpose of this study was to investigate the relationship between dynamic postural stability as measured by the Star Excursion Balance Test (SEBT) and static postural sway assessment as measured by the TechnoBody™ Pro-Kin in female soccer players. A secondary purpose was to determine side-to-side symmetry in this cohort., Methods: A total of 18 female soccer players completed testing on the SEBT and Technobody™ Pro-Kin balance device. Outcome measures were anterior, posterior medial, and posterior lateral reaches from the SEBT and center of pressure in the x- and y-axes as well as SD of movement in the forward/backward and medial/lateral directions from the force plate on left and right legs. Bivariate correlations were determined between the 8 measures. In addition, paired Wilcoxon signed-rank tests were performed to determine similarity between limb scores., Results: All measures on both the SEBT and postural sway assessment were significantly correlated when comparing dominant with nondominant lower-extremities with the exception of SD of movement in both x- and y-axes. When correlating results of the SEBT with postural sway assessment, a significant correlation was found between the SEBT right lower-extremity posterior lateral reach (r = .567, P < .05) and summed SEBT (r = .486, P < .05) and the center of pressure in the y-axis. A significant correlation was also found on the left lower-extremity, with SD of forward/backward movement and SEBT posterior medial reach (r = -.511, P < .05)., Conclusions: Dynamic postural tests and static postural tests provide different information to the overall assessment of balance in female soccer players. Relationship between variables differed based on the subject's lower-extremity dominance.

A dominant Antarctic ecological paradigm suggests that winter sea ice is generally the main feeding ground for krill larvae. Observations from our winter cruise to the southwest Atlantic sector of the Southern Ocean contradict this view and present the first evidence that the pack-ice zone is a food-poor habitat for larval development. In contrast, the more open marginal ice zone provides a more favourable food environment for high larval krill growth rates. We found that complex under-ice habitats are, however, vital for larval krill when water column productivity is limited by light, by providing structures that offer protection from predators and to collect organic material released from the ice. The larvae feed on this sparse ice-associated food during the day. After sunset, they migrate into the water below the ice (upper 20 m) and drift away from the ice areas where they have previously fed. Model analyses indicate that this behaviour increases both food uptake in a patchy food environment and the likelihood of overwinter transport to areas where feeding conditions are more favourable in spring.

Prior studies have explored variables that had predictive relationships with National Physical Therapy Examination (NPTE) score or NPTE failure. The purpose of this study was to explore whether certain variables were predictive of test-takers' first-time score on the NPTE., Subjects: The population consisted of 134 students who graduated from the university's Professional DPT Program in 2012 to 2014., Methods: This quantitative study used a retrospective design. Two separate data analyses were conducted. First, hierarchical linear multiple regression (HMR) analysis was performed to determine which variables were predictive of first-time NPTE score. Second, a correlation analysis was performed on all 18 Physical Therapy Clinical Performance Instrument (PT CPI) 2006 category scores obtained during the first long-term clinical rotation, overall PT CPI 2006 score, and NPTE passage., Results: With all variables entered, the HMR model predicted 39% of the variance seen in NPTE scores. The HMR results showed that physical therapy program first-year GPA (1PTGPA) was the strongest predictor and explained 24% of the variance in NPTE scores (b=0.572, p<0.001). The correlational analysis found no statistically significant correlation between the 18 PT CPI 2006 category scores, overall PT CPI 2006 score, and NPTE passage., Discussion: As 1PTGPA had the most significant contribution to prediction of NPTE scores, programs need to monitor first-year students who display academic difficulty. PT CPI version 2006 scores were significantly correlated with each other, but not with NPTE score or NPTE passage. Both tools measure many of the same professional requirements but use different modes of assessment, and they may be considered complementary tools to gain a full picture of both the student's ability and skills.

Background: The purpose of this qualitative study was to assess the perceptions of Doctor of Physical Therapy (DPT) students in performing collegiate athletes' strength and conditioning training., Methods: Four DPT students with the Certified Strength and Conditioning Specialist (CSCS) credential voluntarily provided collegiate athletes strength and conditioning training. Students were interviewed to obtain their perceptions of how the experience impacted performance in DPT school and perceptions of anticipated future benefits., Results: Seven themes emerged from interviews: improved communication skills, movement analysis experience, improved time management/organization, increased understanding of exercises, attention to psychosocial aspects, interprofessional experience, and improved performance in coursework., Conclusion: DPT students with the CSCS credential perceived benefits from performing strength and conditioning training outside the standard DPT curriculum.

The availability of micronutrients is a key factor that affects primary productivity in High Nutrient Low Chlorophyll (HNLC) regions of the Southern Ocean. Nutrient supply is governed by a range of physical, chemical and biological processes, and there are significant feedbacks within the ecosystem. It has been suggested that baleen whales form a crucial part of biogeochemical cycling processes through the consumption of nutrient-rich krill and subsequent defecation, but data on their contribution are scarce. We analysed the concentration of iron, cadmium, manganese, cobalt, copper, zinc, phosphorus and carbon in baleen whale faeces and muscle, and krill tissue using inductively coupled plasma mass spectrometry. Metal concentrations in krill tissue were between 20 thousand and 4.8 million times higher than typical Southern Ocean HNLC seawater concentrations, while whale faecal matter was between 276 thousand and 10 million times higher. These findings suggest that krill act as a mechanism for concentrating and retaining elements in the surface layer, which are subsequently released back into the ocean, once eaten by whales, through defecation. Trace metal to carbon ratios were also higher in whale faeces compared to whale muscle indicating that whales are concentrating carbon and actively defecating trace elements. Consequently, recovery of the great whales may facilitate the recycling of nutrients via defecation, which may affect productivity in HNLC areas.

Sea ice can contain high concentrations of dissolved organic carbon (DOC), much of which is carbohydrate-rich extracellular polymeric substances (EPS) produced by microalgae and bacteria inhabiting the ice. Here we report the concentrations of dissolved carbohydrates (dCHO) and dissolved EPS (dEPS) in relation to algal standing stock [estimated by chlorophyll (Chl) a concentrations] in sea ice from six locations in the Southern and Arctic Oceans. Concentrations varied substantially within and between sampling sites, reflecting local ice conditions and biological content. However, combining all data revealed robust statistical relationships between dCHO concentrations and the concentrations of different dEPS fractions, Chl a, and DOC. These relationships were true for whole ice cores, bottom ice (biomass rich) sections, and colder surface ice. The distribution of dEPS was strongly correlated to algal biomass, with the highest concentrations of both dEPS and non-EPS carbohydrates in the bottom horizons of the ice. Complex EPS was more prevalent in colder surface sea ice horizons. Predictive models (validated against independent data) were derived to enable the estimation of dCHO concentrations from data on ice thickness, salinity, and vertical position in core. When Chl a data were included a higher level of prediction was obtained. The consistent patterns reflected in these relationships provide a strong basis for including estimates of regional and seasonal carbohydrate and dEPS carbon budgets in coupled physical-biogeochemical models, across different types of sea ice from both polar regions.