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In-situ marine cloud droplet number concentrations (CDNCs), cloud condensation nuclei (CCN), and CCN proxies, based on particle sizes and optical properties, are accumulated from seven field campaigns: ACTIVATE; NAAMES; CAMP2EX; ORACLES; SOCRATES; MARCUS; and CAPRICORN2. Each campaign involves aircraft measurements, ship-based measurements, or both. Measurements collected over the North and Central Atlantic, Indo-Pacific, and Southern Oceans, represent a range of clean to polluted conditions in various climate regimes. With the extensive range of environmental conditions sampled, this data collection is ideal for testing satellite remote detection methods of CDNC and CCN in marine environments. Remote measurement methods are vital to expanding the available data in these difficult-to-reach regions of the Earth and improving our understanding of aerosol-cloud interactions. The data collection includes particle composition and continental tracers to identify potential contributing CCN sources. Several of these campaigns include High Spectral Resolution Lidar (HSRL) and polarimetric imaging measurements and retrievals that will be the basis for the next generation of space-based remote sensors and, thus, can be utilized as satellite surrogates.

Abstract. Long-range transport of biogenic emissions from the coast of Antarctica, precipitation scavenging, and cloud processing are the main processes that influence the observed variability in Southern Ocean (SO) marine boundary layer (MBL) condensation nuclei (CN) and cloud condensation nuclei (CCN) concentrations during the austral summer. Airborne particle measurements on the HIAPER GV from north-south transects between Hobart, Tasmania and 62° S during the Southern Ocean Clouds, Radiation Aerosol Transport Experimental Study (SOCRATES) were separated into four regimes comprising combinations of high and low concentrations of CCN and CN. In 5-day HYSPLIT back trajectories, air parcels with elevated CCN concentrations were almost always shown to have crossed the Antarctic coast, a location with elevated phytoplankton emissions relative to the rest of the SO. The presence of high CCN concentrations was also consistent with high cloud fractions over their trajectory, suggesting there was substantial growth of biogenically formed particles through cloud processing. Cases with low cloud fraction, due to the presence of cumulus clouds, had high CN concentrations, consistent with previously reported new particle formation in cumulus outflow regions. Measurements associated with elevated precipitation during the previous 1.5-days of their trajectory had low CCN concentrations indicating CCN were effectively scavenged by precipitation. A course-mode fitting algorithm was used to determine the primary marine aerosol (PMA) contribution which accounted for  0.07 µm) indicated that particle formation occurs more frequently above the MBL; however, the growth of recently formed particles typically occurs in the MBL, consistent with cloud processing and the condensation of volatile compound oxidation products. CCN measurements on the R/V Investigator as part of the second Clouds, Aerosols, Precipitation, Radiation and atmospheric Composition Over the southeRn Ocean (CAPRICORN-2) campaign were also conducted during the same period as the SOCRATES study. The R/V Investigator observed elevated CCN concentrations near Australia, likely due to continental and coastal biogenic emissions. The Antarctic coastal source of CCN from the south as well as CCN sources from the mid-latitudes create a latitudinal gradient in CCN concentration with an observed minimum in the SO between 55° S and 60° S. The SOCRATES airborne measurements are not influenced by Australian continental emissions, but still show evidence of elevated CCN concentrations to the south of 60° S, consistent with biogenic coastal emissions. In addition, a latitudinal gradient in the particle composition is observed; more hygroscopic particles to the north, consistent with a greater fraction of sea salt from PMA, and more sulfate and organic particles to the south, which are likely from biogenic sources in coastal Antarctica.

The use of performance-based funding that ties state higher education appropriations to performance metrics has increased dramatically in recent years, but most programs place at stake a small percent of overall funding. We analyze the effect of two notable exceptions--Ohio and Tennessee--where nearly all state funding is tied to performance measures. Using a difference-in-differences identification strategy along with a synthetic control approach, we find no evidence that these programs improve key academic outcomes.

This article presents the use of the qualitative research method and the challenges that this form of research imposes along with the increasingly systematic reluctance experienced by doctoral students and their chairs. Increasingly, doctoral students are opting for the qualitative approach over that of the traditional quantitative methodology. The qualitative method is an evolutionary process that addresses the phenomenon being investigated and must show a connection to the question or questions being explored. Within this approach, data collection and analysis often lead to additional questions or findings. The article presents examples of the process for developing the evolving concepts from the interviews of the participants. Additional research is needed to transform this process. This article acknowledges the overall approach for doctoral students and other novice researchers to embrace the qualitative research method within the evolutionary structure.

The remoteness and extreme conditions of the Southern Ocean and Antarctic region have meant that observations in this region are rare, and typically restricted to summertime during research or resupply voyages. Observations of aerosols outside of the summer season are typically limited to long-term stations, such as Kennaook/Cape Grim (KCG, 40.7° S, 144.7° E) which is situated in the northern latitudes of the Southern Ocean, and Antarctic research stations, such as the Japanese operated Syowa (SYO, 69.0° S, 39.6° E). Measurements in the mid-latitudes of the Southern Ocean are important, particularly in light of recent observations that highlighted the latitudinal gradient that exists across the region in summertime. Here we present two years (March 2016–March 2018) of observations from Macquarie Island (MQI, 54.5° S, 159.0° E) of aerosol (condensation nuclei larger than 10 nm, CN10) and cloud condensation nuclei (CCN at various supersaturations) concentrations. This important multi-year data set is characterised, and its features are compared with the long-term data sets from KCG and SYO together with those from recent, regionally relevant voyages. CN10 concentrations were the highest at KCG by a factor of ∼50 % across all non-winter seasons compared to the other two stations which were similar (summer medians of 530 cm-3, 426 cm-3 and 468 cm-3 at KCG, MQI and SYO, respectively). In wintertime, seasonal minima at KCG and MQI were similar (142 cm-3 and 152 cm-3, respectively), with SYO being distinctly lower (87 cm-3), likely the result of the reduction in sea spray aerosol generation due to the sea-ice ocean cover around the site. CN10 seasonal maxima were observed at the stations at different times of year, with KCG and MQI exhibiting January maxima and SYO having a distinct February high. Comparison of CCN0.5 data between KCG and MQI showed similar overall trends with summertime maxima and wintertime minima, however KCG exhibited slightly (∼10 %) higher concentrations in summer (medians of 158 cm-3 and 145 cm-3, respectively), whereas KCG showed ∼40 % lower concentrations than MQI in winter (medians of 57 cm-3 and 92 cm-3, respectively). Spatial and temporal trends in the data were analysed further by contrasting data to coincident observations that occurred aboard several voyages of the RSV Aurora Australis and the RV Investigator. Results from this study are important for validating and improving our models, highlight the heterogeneity of this pristine region, and the need for further long-term observations that capture the seasonal cycles. [ABSTRACT FROM AUTHOR]

The decision to replant suboptimal cotton (Gossypium hirsutum L.) stands has become more challenging in recent years because the suggested retail price per bag of replanting seed has increased by more than 25%. Previous studies have justified replanting when = 50% of planted area is occupied by skips = 0.91 m (3 ft). Revision of replanting recommendations was deemed necessary with the introduction of more advanced and accurate plant and skip detection methods. The objective of this study was to update replanting recommendations using unmanned aerial vehicles (UAVs). The study was conducted at three sites in eastern North Carolina during the 2019 and 2020 growing seasons. Each site had an early- and a late-planted trial. Treatment combinations were produced using various ratios of DP 1646 B2XF and DP 493 cotton seed. Simulated replanted plots were planted with 100% DP 1646 B2XF three to four weeks after initial planting. Following emergence, glyphosate and glufosinate were applied to terminate all conventional seedlings and produce random skips. Cotton skips were detected using a Zenmuse X5 RGB sensor mounted on a UAV. Yield was regressed to the percentage of planted area occupied by skips > 0.91 m. In 2019, the replanted treatment did not yield higher than earlier planted treatments but, in 2020, yields were significantly higher in the replanted treatment compared to most earlier planted treatments. The data suggest that a replant should be triggered when 30 to 40% of the planted area is occupied by skips = 0.91 m. [ABSTRACT FROM AUTHOR]

Coral reefs have been found to produce the sulfur compound dimethyl sulfide (DMS), a climatically relevant aerosol precursor predominantly associated with phytoplankton. Until recently, the role of coral reef-derived DMS within the climate system had not been quantified. A study preceding the present work found that DMS produced by corals had negligible longterm climatic forcing at the global-regional scale. However, at sub-daily time scales more typically associated with aerosol and cloud formation, the influence of coral reef-derived DMS on local aerosol radiative effects remains unquantified. The Weather Research and Forecasting - chemistry model (WRF-Chem) has been used in this work to study the role of coral reef-derived DMS at sub-daily time scales for the first time. WRF-Chem was run to coincide with an October 2016 field campaign over the Great Barrier Reef, Queensland, Australia, against which the model was evaluated. After updating the DMS surface water climatology, the model reproduced DMS and sulfur concentrations well. The inclusion of coral reef-derived DMS resulted in no significant change in sulfate aerosol mass or total aerosol number. Subsequently, no direct or indirect aerosol effects were detected. The results suggest that the co-location of the Great Barrier Reef with significant anthropogenic aerosol sources along the Queensland coast prevents coral reef derived-aerosol from having a modulating influence on local aerosol burdens in the current climate. [ABSTRACT FROM AUTHOR]

Aerosol measurements over the Southern Ocean have been identified as critical to an improved understanding of aerosol-radiation and aerosol-cloud interactions, as there currently exists significant discrepancies between model results and measurements in this region. Previous springtime measurements from the East Antarctic seasonal ice zone revealed a significant increase in aerosol number concentrations when crossing the atmospheric polar front into the Polar cell. A return voyage in summer 2017 made a more extensive range of aerosols measurements, including in particular aerosol number concentrations and submicron size distributions. Again, significantly greater aerosol number concentrations were observed in the Polar cell than in the Ferrel cell. Unlike the previous spring voyage however, the polar front was unable to be identified by a step change in aerosol concentration. A possible explanation is that atmospheric mixing across the polar front occurs to a greater degree in summer, therefore weakening the atmospheric boundary at the front. This atmospheric mixing in summer complicates the determination of the polar front location. These changes, together with the increased source of precursors from phytoplankton emissions, are likely to explain the seasonal differences observed in the magnitude of aerosol populations between the Ferrel and Polar cell. In the present analysis, meteorological variables were used to identify different air- masses and then aerosol measurements were compared based on these identifications. CN3 concentrations measured during wind directions indicative of Polar cell airmasses (median 594 cm-3) were larger than those measured during wind directions indicative of Ferrel cell air (median 265 cm-3). CN3 and CCN concentrations were larger during periods where the absolute humidity was less than 4.3 gH2O/ m3, indicative of free tropospheric or Antarctic continental airmasses, compared to other periods of the voyage. These results indicate that a persistently more concentrated aerosol population is present in the Polar cell over the East Antarctic seasonal ice zone, although the observed difference between the two cells may vary seasonally. [ABSTRACT FROM AUTHOR]

Oceans cover over 70 % of the Earth's surface. Ship-based measurements are an important component in developing an understanding of atmosphere of this vast region. A common problem that impacts the quality of atmospheric data collected from marine research vessels is exhaust from both diesel combustion and waste incineration from the ship itself. Described here is an algorithm, developed for the recently commissioned Australian blue-water research vessel (RV) Investigator , that identifies exhaust periods in sampled air. The RV Investigator , with two dedicated atmospheric laboratories, represents an unprecedented opportunity for high-quality measurements of the marine atmosphere. The algorithm avoids using ancillary data such as wind speed and direction, and instead utilises components of the exhaust itself – aerosol number concentration, black carbon concentration, and carbon monoxide and carbon dioxide mixing ratios. The exhaust signal is identified within each of these parameters individually before they are combined and an additional window filter is applied. The algorithm relies heavily on statistical methods, rather than setting thresholds that are too rigid to accommodate potential temporal changes. The algorithm is more effective than traditional wind-based filters in removing exhaust data without removing exhaust-free data, which commonly occurs with traditional filters. In application to the current dataset, the algorithm identifies 26 % of the wind filter's "clean" data as exhaust, and recovers 5 % of data falsely removed by the wind filter. With suitable testing, the algorithm has the potential to be applied to other ship-based atmospheric measurements where suitable measurements exist. [ABSTRACT FROM AUTHOR]

Preemergence herbicides often negatively affect establishment of sprigged hybrid bermudagrass (Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt-Davy). However, limited research has quantified the effects of preemergence herbicides on establishment and tensile strength of warm-season turfgrass species commonly grown as sod in the southeastern United States. Field research was conducted at Mississippi State University in 2016 and 2017 to evaluate the effects of atrazine, atrazine + S-metolachlor, dithiopyr, flumioxazin, indaziflam, liquid- and granular-applied oxadiazon, S-metolachlor, pendimethalin, prodiamine, and simazine on grow-in time and tensile strength of newly sprigged 'Latitude 36' hybrid bermudagrass. Plots (4.65 m²) were sprigged at a rate of 44 m³ ha-1 (468 US bushels ac-1), and preemergence herbicide treatments were applied at the recommended labeled rates 1 d after planting. Dithiopyr, flumioxazin, S-metolachlor, and indaziflam increased days to reach 50% hybrid bermudagrass cover in both 2016 and 2017. Normalized difference vegetative index and relative chlorophyll index were similarly affected. No herbicide treatments reduced sod tensile strength in either year; however, prodiamine, pendimethalin, dithiopyr, flumioxazin, and S-metolachlor unexpectedly increased sod tensile strength in 2017. [ABSTRACT FROM AUTHOR]

Ship-based measurements are an important component in developing an understanding of the global atmosphere. A common problem that impacts the quality of atmospheric data collected from marine research vessels is exhaust from both diesel combustion and waste incineration from the ship itself. Described here is an algorithm, developed for the recently commissioned Australian blue-water Research Vessel (RV) Investigator, that identifies exhaust periods in sampled air. The RV Investigator, with two dedicated atmospheric laboratories, represents an unprecedented opportunity for high quality measurements of the marine atmosphere. The algorithm avoids using ancillary data such as wind speed and direction, and instead utilises components of the exhaust itself - aerosol number concentration, black carbon concentration, and carbon monoxide and carbon dioxide mixing ratios. The exhaust signal is identified within each of these parameters individually before they are combined and an additional window filter is applied. The algorithm relies heavily on statistical methods, rather than setting thresholds that are too rigid to accommodate potential temporal changes. The algorithm is more effective than traditional wind-based filters in removing exhaust data without removing exhaust-free data which commonly occurs with traditional filters. With suitable testing, the algorithm has the potential to be applied to other ship-based atmospheric measurements where suitable measurements exist. [ABSTRACT FROM AUTHOR]

As Great Britain reaches 50 years of LBGTQ+ legislation, making it illegal to persecute an individual based on their sexual identity, not everywhere in the world is so enlightened. In some parts of the world, the act of homosexuality is punishable by law, with people sentenced to incarceration or even death. For some people, trying to leave their country and claim asylum in another part of the world is the only way people can truly be themselves. This paper is based on the case studies of two male clients who are both waiting for an asylum decision, with both cases based on their sexuality, and the approach used in therapy sessions, specifically focusing on not only coming to terms with their own persecution, moving from shame of their own culture, but also working with frustration and the re-shaming effects of proving one’s sexuality. The overall objective is to create an argument for Dramatherapy when working with complex trauma, shame and raising awareness of the lesser-known work of Dramatherapy and asylum seekers. [ABSTRACT FROM AUTHOR]

In rice, several allergens have been identified such as the non-specific lipid transfer protein-1, the α-amylase/trypsin-inhibitors, the α-globulin, the 33 kDa glyoxalase I (Gly I), the 52–63 kDa globulin, and the granule-bound starch synthetase. The goal of the present study was to define optimal rice extraction and detection methods that would allow a sensitive and reproducible measure of several classes of known rice allergens. In a three-laboratory ring-trial experiment, several protein extraction methods were first compared and analyzed by 1D multiplexed SDS-PAGE. In a second phase, an inter-laboratory validation of 2D-DIGE analysis was conducted in five independent laboratories, focusing on three rice allergens (52 kDa globulin, 33 kDa glyoxalase I, and 14–16 kDa α-amylase/trypsin inhibitor family members). The results of the present study indicate that a combination of 1D multiplexed SDS-PAGE and 2D-DIGE methods would be recommended to quantify the various rice allergens. Representative multiplexed detection and 2D-DIGE profile of rice endogenous allergens. [ABSTRACT FROM PUBLISHER]

* STUDY DESIGN: Retrospective cohort. * BACKGROUND: Patient-classification subgroupings may be important prognostic factors explaining outcomes. * OBJECTIVES: To determine effects of adding classification variables (McKenzie syndrome and pain patterns, including centralization and directional preference; Symptom Checklist Back Pain Prediction Model [SCL BPPM]; and the Fear-Avoidance Beliefs Questionnaire subscales of work and physical activity) to a baseline risk-adjusted model predicting functional status (FS) outcomes. * METHODS: Consecutive patients completed a battery of questionnaires that gathered information on 11 risk-adjustment variables. Physical therapists trained in Mechanical Diagnosis and Therapy methods classified each patient by McKenzie syndromes and pain pattern. Functional status was assessed at discharge by patient-reported outcomes. Only patients with complete data were included. Risk of selection bias was assessed. Prediction of discharge FS was assessed using linear stepwise regression models, allowing 13 variables to enter the model. Significant variables were retained in subsequent models. Model power (R²) and beta coefficients for model variables were estimated. * RESULTS: Two thousand sixty-six patients with lumbar impairments were evaluated. Of those, 994 (48%), 10 (<1%), and 601 (29%) were excluded due to incomplete psychosocial data, McKenzie classification data, and missing FS at discharge, respectively. The final sample for analyses was 723 (35%). Overall R² for the baseline prediction FS model was 0.40. Adding classification variables to the baseline model did not result in significant increases in R². McKenzie syndrome or pain pattern explained 2.8% and 3.0% of the variance, respectively. When pain pattern and SCL BPPM were added simultaneously, overall model R² increased to 0.44. Although none of these increases in R² were significant, some classification variables were stronger predictors compared with some other variables included in the baseline model. * CONCLUSION: The small added prognostic capabilities identified when combining McKenzie or pain-pattern classifications with the SCL BPPM classification did not significantly improve prediction of FS outcomes in this study. Additional research is warranted to investigate the importance of classification variables compared with those used in the baseline model to maximize predictive power. [ABSTRACT FROM AUTHOR]

STUDY DESIGN: Retrospective cohort. OBJECTIVES: In subjects with neck pain, the present study aimed (1) to describe the prevalence of centralization (CEN), noncentralization (non-CEN), directional preference (DP), and no directional preference (no DP); (2) to determine if age, sex, fear-avoidance beliefs about physical activity, number of comorbid conditions, or symptom duration varies among subjects who demonstrate CEN versus non-CEN and DP versus no DP; and (3) to determine if CEN and/or DP are associated with changes in function and pain. BACKGROUND: CEN and DP are prevalent among patients with low back pain and should be considered when determining treatment strategies and predicting outcomes; however, these findings are not well investigated in patients with neck pain. METHODS: Three hundred four subjects contributed data. CEN and DP prevalence were calculated, as was the association between CEN and DP, and age, sex, number of comorbid conditions, fear-avoidance beliefs, and symptom duration. Multivariate models assessed whether CEN and DP predicted change in function and pain. RESULTS: CEN and DP prevalence were 0.4 and 0.7, respectively. Younger subjects and those with fewer comorbid conditions were more likely to centralize; however, subjects who demonstrated DP were more likely to have acute symptoms. Subjects who centralized experienced, on average, a 3.6-point (95% confidence interval: -0.3, 7.4) improvement in function scores, whereas subjects with a DP averaged a 5.4-point (95% confidence interval: 0.8, 10.0) improvement. Neither CEN nor DP was associated with pain outcomes. CONCLUSION: DP and, to a lesser extent, CEN represent evaluation categories that are associated with improvements in functional outcomes. [ABSTRACT FROM AUTHOR]

The article discusses highlights of a study that determines the association between directional preference (DP) and centralization in individuals with low back pain. The study methodology is discussed. The study showed that the overall prevalence of DP and centralized (CEN) was 60 percent and 41 percent, respectively. The study concludes with a suggestion that classification by pain patten and DP can improved the ability of a therapist to provide a short-term prognosis for pain and function outcomes.