Nitrate reduction in the vicinity of tile drains

The fate of nitrates as they travel through a long porous column at a slow rate was observed in this study with temperature and substrate materials variable. During a one month period of flow with pore velocities averaging up to 21 centimeters per day, losses as high as 89 percent were found for a methanol treatment at 24˚ while for 13˚ losses were reduced to 46 percent. A sawdust substrate material resulted in very little reduction of nitrate concentrations at 24˚ and actual increases (presumably from mineralization) at 13˚. Since methanol was found to be an effective means of removing nitrate from a slowly moving stream of water at 0 temperatures as low as 13 C, it will be used as a standard in future field studies to evaluate less expensive substrate materials.U.S. Geological SurveyU.S. Department of the InteriorOpe

An Exploration of Alternative Scoring Methods Using Curriculum-Based Measurement in Early Writing

This manuscript describes two empirical studies of alternative scoring procedures used with curriculum-based measurement in writing (CBM-W). Study 1 explored the technical adequacy of a trait-based rubric in first grade. Study 2 explored the technical adequacy of a trait-based rubric, production-dependent, and production-independent scores in third grade. Results of Study 1 suggest that the rubric holds promise as a valid measure of sentence writing ability in first grade and has utility as a supplemental scoring procedure when using CBM-W as a screening tool. Results of Study 2 show that correct word sequences maintained the highest correlation coefficients across time with the trait-based rubric, but the other scoring procedures might offer promise as reliable alternative scoring methods. However, high internal correlations among the text features of the rubric along with highly variable interrater reliability suggest that caution must be taken in interpreting results

Scoring measures of word dictation curriculum-based measurement in writing: Effects of incremental administration

Spelling has been identified as a key transcription skill that emerges during the elementary years as students learn how to write and subsequently develop fluency with writing, making the assessment of spelling a critical component of evaluation systems within schools. This includes the use of curriculum-based measures of writing (CBM-W). This study examined the extent to which word dictation CBM-W administered during the Fall, Winter, and Spring of an academic year maintained technical adequacy across 1-min time intervals in grades 1–3. Results revealed moderate predictive and concurrent validity estimates with the Spelling subtest of the Weschler Individual Achievement Test-III. Statistically significant differences existed between and within grade levels across each minute of administration and across Fall, Winter, and Spring time points for all scoring procedures

Evidence for enhanced convection of North Pacific Intermediate Water to the low-latitude Pacific under glacial conditions

We provide high-resolution foraminiferal stable carbon isotope (δ13C) records from the subarctic Pacific and Eastern Equatorial Pacific (EEP) to investigate circulation dynamics between the extra-tropical and tropical North Pacific during the past 60 kyr. We measured the δ13C composition of the epibenthic foraminiferal species Cibicides lobatulus from a shallow sediment core recovered from the western Bering Sea (SO201-2-101KL; 58°52.52’N, 170°41.45’E; 630 m water depth) to reconstruct past ventilation changes close to the source region of Glacial North Pacific Intermediate Water (GNPIW). Information regarding glacial changes in the δ13C of sub-thermocline water masses in the EEP is derived from the deep-dwelling planktonic foraminifera Globorotaloides hexagonus at ODP Site 1240 (00°01.31’N, 82°27.76’W; 2921 m water depth). Apparent similarities in the long-term evolution of δ13C between GNPIW, intermediate waters in the eastern tropical North Pacific and sub-thermocline water masses in the EEP suggest the expansion of relatively 13C-depleted, nutrient-enriched, and northern-sourced intermediate waters to the equatorial Pacific under glacial conditions. Further, it appears that additional influence of GNPIW to the tropical Pacific is consistent with changes in nutrient distribution and biological productivity in surface-waters of the glacial EEP. Our findings highlight potential links between North Pacific mid-depth circulation changes, nutrient cycling, and biological productivity in the equatorial Pacific under glacial boundary conditions

Using Data-Based Instruction to Support Struggling Elementary Writers

Writing is a critical academic and life skill, but many school-age children struggle with the complexity of written expression. Given the importance of writing, there is a clear need for a systematic approach to identifying and supporting struggling writers, including writers with learning and emotional disabilities. One such approach is known as data-based instruction (DBI). This article presents an overview of DBI and guidance on how educators can use the DBI steps with assessment data to inform their classroom writing instruction. Additional resources are shared to support teachers in using DBI with their struggling writers and writers with learning and emotional disabilities

Pulses of enhanced North Pacific Intermediate Water ventilation from the Okhotsk Sea and Bering Sea during the last deglaciation

Under modern conditions only North Pacific Intermediate Water is formed in the Northwest Pacific Ocean. This situation might have changed in the past. Recent studies with General Circulation Models indicate a switch to deep-water formation in the Northwest Pacific during Heinrich Stadial 1 (17.5–15.0 kyr) of the last glacial termination. Reconstructions of past ventilation changes based on paleoceanographic proxy records are still insufficient to test whether a deglacial mode of deep-water formation in the North Pacific Ocean existed. Here we present deglacial ventilation records based on radiocarbon-derived ventilation ages in combination with epibenthic stable carbon isotopes from the Northwest Pacific including the Okhotsk Sea and Bering Sea, the two potential source regions for past North Pacific ventilation changes. Evidence for most rigorous ventilation of the mid-depth North Pacific occurred during Heinrich Stadial 1 and the Younger Dryas, simultaneous to significant reductions in Atlantic Meridional Overturning Circulation. Concurrent changes in δ13C and ventilation ages point to the Okhotsk Sea as driver of millennial-scale changes in North Pacific Intermediate Water ventilation during the last deglaciation. Our records additionally indicate that changes in the δ13C intermediate water (700–1750 m water depth) signature and radiocarbon-derived ventilation ages are in antiphase to those of the deep North Pacific Ocean (>2100 m water depth) during the last glacial termination. Thus, intermediate and deep-water masses of the Northwest Pacific have a differing ventilation history during the last deglaciation

Exploration of New Complexity Metrics for Curriculum-Based Measures of Writing

Researchers and practitioners have questioned whether scoring procedures used with curriculum-based measures of writing (CBM-W) capture growth in complexity of writing. We analyzed data from six independent samples to examine two potential scoring metrics for picture word CBM-W (PW), a sentence-level CBM task. Correct word sequences per response (CWSR) and words written per response (WWR) were compared with the current standard metric of correct word sequences (CWS). Linear regression analyses indicated that CWSR predicted scores on standardized norm-referenced criterion measures in more samples than did WWR or CWS. Future studies should explore the capacity of CWSR and WWR to show growth over time, stability, diagnostic accuracy, and utility for instructional decision making

Deglacial Variability in Okhotsk Sea Intermediate Water Ventilation and Biogeochemistry: Implications for North Pacific Nutrient Supply and Productivity

Highlights • Multi-proxy, multi-site reconstruction of Okhotsk Sea palaeo-productivity and mid-depth ventilation changes from 8 to 18 ka. • Link between hinterland river discharge and downstream Okhotsk Sea Intermediate Water (OSIW) ventilation/nutrient signatures. • Surplus Fe, Si(OH)4 export in OSIW during Bølling-Allerød to pelagic Pacific supported transient nutrient-replete conditions. • Subarctic and subtropical Pacific gyres disconnected during Bølling-Allerød, with restricted OSIW flow to lower latitudes. • Deglacial OSIW export and mid-depth Pacific biogeochemistry modulate millennial-scale regional CO2 source/sink conditions. The modern North Pacific plays a critical role in marine biogeochemical cycles, as an oceanic sink of CO2 and by bearing some of the most productive and least oxygenated waters of the World Ocean. The capacity to sequester CO2 is limited by efficient nutrient supply to the mixed layer, particularly from deeper water masses in the Pacific's subarctic and marginal seas. The region is in addition only weakly ventilated by North Pacific Intermediate Water (NPIW), which receives its characteristics from Okhotsk Sea Intermediate Water (OSIW). Here, we present reconstructions of intermediate water ventilation and productivity variations in the Okhotsk Sea that cover the last glacial termination between eight and 18 ka, based on a set of high-resolution sediment cores from sites directly downstream of OSIW formation. In a multi-proxy approach, we use total organic carbon (TOC), chlorin, biogenic opal, and CaCO3 concentrations as indicators for biological productivity. C/N ratios and XRF scanning-derived elemental ratios (Si/K and Fe/K), as well as chlorophycean algae counts document changes in Amur freshwater and sediment discharge that condition the OSIW. Stable carbon isotopes of epi- and shallow endobenthic foraminifera, in combination with 14C analyses of benthic and planktic foraminifera imply decreases in OSIW oxygenation during deglacial warm phases from c. 14.7 to 13 ka (Bølling-Allerød) and c. 11.4 to 9 ka (Preboreal). No concomitant decreases in Okhotsk Sea benthic-planktic ventilation ages are observed, in contrast to nearby, but southerly locations on the Japan continental margin. We attribute Okhotsk Sea mid-depth oxygenation decreases in times of enhanced organic matter supply to maxima in remineralization within OSIW, in line with multi-proxy evidence for maxima in primary productivity and supply of organic matter. Sedimentary C/N and Fe/K ratios indicate more effective entrainment of nutrients into OSIW and thus an increased nutrient load of OSIW during deglacial warm periods. Correlation of palynological and sedimentological evidence from our sites with hinterland reference records suggests that millennial-scale changes in OSIW oxygen and nutrient concentrations were largely influenced by fluvial freshwater runoff maxima from the Amur, caused by a deglacial northeastward propagation of the East Asian Summer Monsoon that increased precipitation and temperatures, in conjunction with melting of permafrost in the Amur catchment area. We suggest that OSIW ventilation minima and the high lateral supply of nutrients and organic matter during the Allerød and Preboreal are mechanistically linked to concurrent maxima in nutrient utilization and biological productivity in the subpolar Northwest Pacific. In this scenario, increased export of nutrients from the Okhotsk Sea during deglacial warm phases supported subarctic Pacific shifts from generally Fe-limiting conditions to transient nutrient-replete regimes through enhanced advection of mid-depth nutrient- and Fe-rich OSIW into the upper ocean. This mechanism may have moderated the role of the subarctic Pacific in the deglacial CO2 rise on millennial timescales by combining the upwelling of old carbon-rich waters with a transient delivery of mid-depth-derived bio-available Fe and silicate

Getting More From Your Maze: Examining Differences in Distractors

The present study examined the technical adequacy of maze-selection tasks constructed in 2 different ways: typical versus novel. We selected distractors for each measure systematically based on rules related to the content of the passage and the part of speech of the correct choice. Participants included 262 middle school students who were randomly assigned to 1 of the 2 maze formats. Scoring of the maze included both correct and correct-minus-incorrect scores. Students completed 3 criterion-reading tests: the Scholastic Reading Inventory, the AIMSweb R-Maze, and a high-stakes state assessment (the Missouri Assessment Program). Alternate-forms reliability was similar across maze formats; however, with regard to scoring procedure, reliability coefficients were consistently higher for correct than for correct-minus-incorrect scores. Validity coefficients were also similar across format with 1 exception: The coefficients for typical maze scores were stronger when compared with the Missouri Assessment Program scores than the coefficients for novel maze scores