Early Portion Research Articles

Colonization of drying temporary wetlands by Coptotomus loticus (Coleoptera: Dytiscidae): a unique strategy for an aquatic wetland insect

Predaceous diving beetles (Coleoptera: Dytiscidae) are well-known for their ability to colonize both permanent and temporary aquatic habitats. They often move predictably between these two habitats, colonizing recently flooded habitat and returning to permanent habitat during the dry-down phase. However, Coptotomus loticus Hilsenhoff does not appear to utilize this same strategy. The objective of our study was to investigate the spatial and temporal patterns of C. loticus distribution in wetland habitats of the southeastern USA. Floodplain wetlands were sampled seasonally over 2 years (a drought year and a flood year), and Carolina bays were sampled seasonally over 3 years. During the drought year, C. loticus remained primarily in permanent water bodies on the floodplain. During the flood year, C. loticus utilized temporary habitats on the floodplain to a greater degree than in the drought year. High densities of C. loticus were more common in temporary habitat during the latter half of the year (dry-down phase) versus the early actively-flooding portion of the year. The highest density of C. loticus in Carolina bays was also found during the dry-down phase. These results suggest C. loticus may be accessing temporary wetland habitat in which fish and other vertebrates may be stranded as the habitat dries down. Dytiscids have been known to consume vertebrate carrion, and in this study system, C. loticus may be utilizing the dry-down effect to hone in on stranded vertebrates as a readily available food source, a strategy not yet described among wetland macroinvertebrates. This phenomenon warrants further study in this and other systems, however, to verify its existence across time and space.

Pre-Columbian agriculture, fire, and Spanish contact: A 4200-year record from Laguna Los Mangos, Costa Rica

We present a lake-sediment record of pre-Columbian agriculture and fire history from the lowlands of southern Pacific Costa Rica that captures the arrival of maize agriculture at ca. 3360 cal yr BP in the Diquís subregion of the Gran Chiriquí archeological region. Our 4200-year record from Laguna Los Mangos begins 1000 to 2000 years earlier than other lake records from the region and provides the first microfossil and geochemical evidence of vegetation and fire prior to the establishment of maize agriculture. This early portion of the record shows evidence of fire events associated with land clearance or field preparation and maintenance for subsistence activities. Alternatively, these were wildfires ignited unintentionally by people or naturally by lightning or volcanism. Evidence of early maize by ca. 3200 cal yr BP was found at Laguna Zoncho in the southeastern section of the Diquís subregion. Our discovery of early maize agriculture at ca. 3360 cal yr BP in the Laguna Los Mangos watershed in the northwestern portion of the Diquís subregion indicates a rapid adoption of maize agriculture in the region after initial introduction. Pre-Columbian agriculture and fire activity at Los Mangos is nearly continual until historic times, but with a decline after ca. 1170 cal yr BP, coincident with the early Terminal Classic Drought (TCD). We infer a pronounced drying of the lowland environment at Laguna Los Mangos based on a depositional hiatus in the record at ca. 950 during late TCD. Agricultural proxies indicate reduced watershed activity during the ‘Little Ice Age’ following Spanish contact in southern Central America until the 20th century.

How Do You Deal With Uncertainty? Cochlear Implant Users Differ in the Dynamics of Lexical Processing of Noncanonical Inputs.

Work in normal-hearing (NH) adults suggests that spoken language processing involves coping with ambiguity. Even a clearly spoken word contains brief periods of ambiguity as it unfolds over time, and early portions will not be sufficient to uniquely identify the word. However, beyond this temporary ambiguity, NH listeners must also cope with the loss of information due to reduced forms, dialect, and other factors. A recent study suggests that NH listeners may adapt to increased ambiguity by changing the dynamics of how they commit to candidates at a lexical level. Cochlear implant (CI) users must also frequently deal with highly degraded input, in which there is less information available in the input to recover a target word. The authors asked here whether their frequent experience with this leads to lexical dynamics that are better suited for coping with uncertainty. Listeners heard words either correctly pronounced (dog) or mispronounced at onset (gog) or offset (dob). Listeners selected the corresponding picture from a screen containing pictures of the target and three unrelated items. While they did this, fixations to each object were tracked as a measure of the time course of identifying the target. The authors tested 44 postlingually deafened adult CI users in 2 groups (23 used standard electric only configurations, and 21 supplemented the CI with a hearing aid), along with 28 age-matched age-typical hearing (ATH) controls. All three groups recognized the target word accurately, though each showed a small decrement for mispronounced forms (larger in both types of CI users). Analysis of fixations showed a close time locking to the timing of the mispronunciation. Onset mispronunciations delayed initial fixations to the target, but fixations to the target showed partial recovery by the end of the trial. Offset mispronunciations showed no effect early, but suppressed looking later. This pattern was attested in all three groups, though both types of CI users were slower and did not commit fully to the target. When the authors quantified the degree of disruption (by the mispronounced forms), they found that both groups of CI users showed less disruption than ATH listeners during the first 900 msec of processing. Finally, an individual differences analysis showed that within the CI users, the dynamics of fixations predicted speech perception outcomes over and above accuracy in this task and that CI users with the more rapid fixation patterns of ATH listeners showed better outcomes. Postlingually deafened CI users process speech incrementally (as do ATH listeners), though they commit more slowly and less strongly to a single item than do ATH listeners. This may allow them to cope more flexible with mispronunciations.

Use of naturally sourced feed additives (lactobacillus fermentation products and enzymes) in growing and finishing steers: Effects on performance, carcass characteristics and blood metabolites

An experiment was conducted to evaluate the use of naturally sourced feed additives that consisted of lactobacillus fermentation products (LFPs), plant based enzymes and prebiotics as alternatives to antibiotics in the diets of growing and finishing beef steers. The feed additives were two commercial products: Bio-Lac Plus (BL) and Boviglo (BG). During growing, 75 crossbred steers (initial body weight, 279 ± 4.9 kg) were blocked by weight and randomly allocated into five treatments: control; implant (IM; Elanco-Component TE-100 with Tylan); implant + antibiotics (330 mg monensin +110 mg chlortetracycline/steer/d; IMAT); implant + BL (30 g/steer/d BL; IMBL); and BG (5 mL/steer/d). Steers were fed a basal diet consisting of 600 g/kg corn silage, 350 g/kg dry-rolled barley grain, and 50 g/kg protein, vitamin and mineral supplement (dry matter [DM] basis). When the 112 d growing period finished, steers were maintained on the same treatments and gradually adapted to finishing diet within one month. Steers were not implanted during the 112 d finishing period. The finishing diet consisted of 100 g/kg corn silage, 870 g/kg dry-rolled barley grain, and 30 g/kg vitamin and mineral supplement (DM basis). Steers were housed in individual pens with feed intake measured individually over the 224 d experiment. During the growing period, no treatment effect on DM intake was observed; however, final body weight, ADG and G:F were highest (P < 0.05) with IM, IMAT and IMBL, intermediate with BG and lowest with control. A treatment × day on feed interaction (P < 0.05) occurred for ADG, which was higher (P < 0.01) with IMBL than control or other treatments during first 14 days on-feed. Feeding BG improved (P < 0.01) ADG and G:F versus control animals. In addition, the need to use therapeutic antimicrobials was lower (P < 0.01) for all treatments, in particularly with BL versus control. During finishing, s neither BL or BG effected growth performance or carcass characteristics. Greater (P < 0.05) antioxidant capacities were observed in steers fed IMAT than steers fed IMBL and BG. These results indicate that supplementation of BL or BG improved ADG and feed efficiency during the stressful, early portion of the growing phase, but had no effect during finishing. The results suggest that both BL and BG have the potential to be fed as alternatives to antimicrobial growth promoters in growing steers.

Lateral extra-articular reconstruction length changes during weightbearing knee flexion and pivot shift: A simulation study

IntroductionVariations in the length of lateral extra-articular reconstruction (LER) have been widely investigated during knee flexion but there is no information about length changes during pivot shift. This study sought to assess the changes in LER tension during weightbearing knee flexion in a normal knee and in a computer-simulated pivot-shift scenario. HypothesisPlacing the femoral tunnel posterior and proximal to the lateral femoral epicondyle allows the LER to tighten early in the flexion range during weightbearing (squatting motion) and simulated pivot-shift. Material and methodsA computer model was used to simulate weightbearing knee flexion and pivot shift scenarios. Changes in LER tension were calculated in both scenarios by estimating the distance between six femoral attachment sites (posterior and proximal to the lateral femoral epicondyle) and two tibial tunnel locations: Gerdy's tubercle (GT) and the anterolateral ligament (ALL) anatomic attachment site. ResultsIndependent of the location of the femoral and tibial tunnels, the LER tightened by up to 22% of its resting length during the early portion of weightbearing knee flexion and then relaxed from 40° to 60° of knee flexion. The ALL tibial tunnel position allowed complete LER relaxation at 60° flexion whereas LER using the GT tibial tunnel position remained tighter. In the simulated pivot-shift test, and for all femoral tunnel locations, the LER tightened by 20% to 34% of its resting value for the GT tibial tunnel position and by 11% to 26% for the ALL tibial tunnel position. DiscussionDuring weightbearing knee flexion, placing the femoral tunnel proximal and posterior to the femoral epicondyle was associated with LER tightening in the early degrees of flexion and LER relaxation between 40 and 60° flexion. LER tightening occurred during a simulated pivot-shift test supporting the concept that a posterior and proximal femoral LER tunnel position is most effective during weightbearing knee flexion and altered knee kinematics.

Iterative Spatial Updating During Forward Linear Walking Revealed Using a Continuous Pointing Task

The continuous pointing task uses target-directed pointing responses to determine how perceived distance traveled is estimated during forward linear walking movements. To more precisely examine the regulation of this online process, the current study measured upper extremity joint angles and step-cycle kinematics in full vision and no-vision continuous pointing movements. Results show perceptual under-estimation of traveled distance in no-vision trials compared to full vision trials. Additionally, parsing of the shoulder plane of elevation trajectories revealed discontinuities that reflected this perceptual under-estimation and that were most frequently coupled with the early portion of the right foot swing phase of the step-cycle. This suggests that spatial updating may be composed of discrete iterations that are associated with gait parameters.

Stochastic modelling of rainfall for the island of Ireland

This paper analyses a recently created continuous 305-year (1711–2016) monthly rainfall series for the island of Ireland. The findings are as follows. The excess skewness in the monthly series may be eradicated by using a Box-Cox transformation with parameter equal to 0.6: a value very similar to that found for the U.K. and its regions. There is no evidence of either an overall stochastic trend or of evolving monthly seasonal patterns, but positive linear trends are found for January, March, and December and a negative linear trend is found for July. Analysis of the seasonal and annual series (which require no transformation) confirms the implication from the monthly data that winters have become progressively wetter and summers progressively drier, with the positive linear trend for winter being twice the size of the negative summer trend. Since there is no trend in either spring or autumn rainfall, annual rainfall shows a positive linear trend. Given that the rainfall series exists for over three centuries, breaks and structural shifts in the model were investigated. Five breaks were identified, three of which occurred in the early portion of the series during the eighteenth century. However, trends were found to be much more stable from the middle of the nineteenth century. For the seasonal series, only a single break, at 1790 for the winter series, was found: it was only after this break that winters became wetter; before then, winter rainfall had a negative trend. In terms of predictability, predictions from the model were found to be more volatile during the second half of the eighteenth century and again from 1976 onwards.

An investigation of listener envelopment utilizing a spherical microphone array and third-order ambisonics reproduction.

Listener envelopment (LEV), the sense of being surrounded by the sound field, is a perception that has been found to be related to the overall impression of a concert hall. The purpose of this study was to investigate the relationship between the perception of LEV and the direction and arrival time of energy from spatial room impulse responses (IRs). IRs were obtained in a 2000-seat concert hall using a 32-channel spherical microphone array and analyzed using a third-order plane wave decomposition. Additionally, the IRs were convolved with anechoic music and processed for third-order Ambisonic reproductions and presented to subjects over a 30-loudspeaker array. Instances were found in which the energy in the late sound field did not correlate with LEV ratings as well as energy in a 70-100 ms time window. Follow-up listening tests were conducted with hybrid IRs containing portions of an enveloping IR and an unenveloping IR with crossover times ranging from 40 to 140 ms. Additional hybrid IRs were studied wherein portions of the spatial IRs were collapsed into all frontal energy with crossover times ranging from 40 to 120 ms. The tests confirmed that much of the important LEV information exists in the early portion of these IRs.

Wine quality rapid detection using a compact electronic nose system: Application focused on spoilage thresholds by acetic acid

It is crucial for the wine industry to have methods like electronic nose systems (E-Noses) for real-time monitoring thresholds of acetic acid in wines, preventing its spoilage or determining its quality. In this paper, we prove that the portable and compact self-developed E-Nose, based on thin film semiconductor (SnO2) sensors and trained with an approach that uses deep Multilayer Perceptron (MLP) neural network, can perform early detection of wine spoilage thresholds in routine tasks of wine quality control. To obtain rapid and online detection, we propose a method of rising-window focused on raw data processing to find an early portion of the sensor signals with the best recognition performance. Our approach was compared with the conventional approach employed in E-Noses for gas recognition that involves feature extraction and selection techniques for preprocessing data, succeeded by a Support Vector Machine (SVM) classifier. The results evidence that is possible to classify three wine spoilage levels in 2.7 s after the gas injection point, implying in a methodology 63 times faster than the results obtained with the conventional approach in our experimental setup.

Transient Response Estimation of an Offshore Wind Turbine Support System

To obtain reliable estimations of the dynamic responses of high-rising marine structures such as offshore wind turbines with obvious nonzero initial conditions, traditional frequency-domain methods cannot be employed because they provide only steady-state results. A novel frequency-domain transient response estimation method for offshore wind turbines is presented in this paper. This method builds upon a recent, significant theoretical development, which found that expressions of external loads in the frequency domain can be obtained by discretizing their eigenvalues and corresponding complex coefficients rather than directly by discrete Fourier transform (DFT) analysis, which makes it possible to deal with nonzero conditions in the frequency domain. One engineering advantage of this approach is its computational efficiency, as the motion equations of the system can be solved in the frequency domain. In order to demonstrate this approach, a case of a monopile-supported wind turbine with nonzero initial conditions was investigated. The numerical results indicate that the approach matches well with the time-domain method, except for a small, earlier portion of the estimated responses. A second case study of a sophisticated, jacket support wind turbine, involving practical issues such as complex external loads and computation efficiency, is also discussed, and comparisons of the results with the time-domain method and traditional frequency-domain method using the commercial software ANSYS are included here.

Differential Marking of Embryos by Location and Date of Release Reveals Within‐River Natal Homing and Parental Influence on Progeny Return Timing in Sockeye Salmon

AbstractThe tendencies of salmon and trout to spawn in proximity to their natal sites and follow the parental timing of breeding are fundamental to their population structure and also affect the performance of enhancement facilities. Specifically, an understanding of how parental spawning date and offspring release location affect the timing and place of breeding by returning adults is important for the evaluation of hatchery supplementation programs and their integration with sympatric naturally spawning populations. We collected Sockeye Salmon Oncorhynchus nerka carcasses in the Cedar River, Washington, over three spawning seasons to evaluate spawn timing and distribution. Thermal marks on the otoliths of hatchery‐origin carcasses allowed assignment of fish to parents that spawned in the early, middle, and late parts of the season and to fry release locations in the lower, middle, and upper parts of the river. The early portion of the spawning run was composed of a higher proportion of hatchery‐origin fish than was the case later in the season. Hatchery‐origin adults that were released early in the spring as fry (from early spawning parents) were recovered early in the season, and those released later in the spring as fry were recovered later in the season. The natural‐origin spawn timing most closely matched the spawn timing of middle and late hatchery fry release groups in all years. Our data also demonstrated a correspondence between hatchery fry release location and adult recovery location; fry released at river kilometer (rkm) 1.0 were recovered 7.0 km lower (median value) in the river than fry released at rkm 21.7 and were recovered 10.0 km lower than fry released at rkm 35.1. These data contribute to the substantial body of evidence that population characteristics of anadromous salmonids are sensitive to influence from fish culture practices—even under benign regimes—because of the strong connections between parental and progeny timing and the fine‐scale homing of salmon to release sites within a river.

Climate model projections for future seasonal rainfall cycle statistics in Northwest Costa Rica

Increasing water scarcity due to rising demand and changes in climate and land use are expected to exert significant stress on water resources in many parts of the world. In many areas, distinctive patterns of seasonal precipitation play an important role in regional ecosystems, economies, and food and energy supplies. Given the inconsistency among climate model precipitation projections, this study develops a statistical approach to better characterize seasonal patterns of precipitation and to assess the potential impact of climate change on these patterns. The method is applied to evaluate the bimodal seasonal pattern of precipitation in northwest Costa Rica as a case study. A Gaussian mixture model is used to describe the bimodal pattern and quantify changes in the seasonal precipitation cycle projected by 19 Coupled General Circulation Models. The model simulations for the current period (1979–2005) are compared with observed monthly precipitation data based on four goodness‐of‐fit metrics to select the best performing models. The monthly bias‐corrected and spatially disaggregated (BCSD) climate projections from the selected models are used to investigate the projected change in the bimodal seasonal pattern, seasonal mean precipitation and interannual variability at the late twenty‐first century. Under RCP8.5, the degree of consistency associated with these BCSD climate projections is found to be higher for the projections of the midsummer drought than that for the early portion of the wet season (early season). For the late portion of the wet season (late season) projections, the degree of consistency is found to be the lowest. The proposed method provides (a) an overall characterization of inconsistencies in climate model projections for the region, (b) more information about the possible changes in the seasonal cycle of precipitation, and (c) the possibility of performing detailed comparison tests among climate models over a set of simulations and projections.

Functional pathways associated with human carotid atheroma: a proteomics analysis.

Advances in large-scale analysis are becoming very useful in understanding health and disease. Here, we used high-throughput mass spectrometry to identify differentially expressed proteins between early and advanced lesions. Carotid endarterectomy samples were collected and dissected into early and advanced atherosclerotic lesion portions. Proteins were extracted and subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Differentially expressed proteins were identified and verified using multiple reaction monitoring (MRM), on which advanced systems biology and enrichment analyses were performed. The identified proteins were further compared to the transcriptomic data of 32 paired samples obtained from early and advanced atherosclerotic lesions. A total of 95 proteins were upregulated, and 117 proteins were downregulated in advanced lesions compared to early atherosclerotic lesions (p < 0.05). The upregulated proteins were associated with proatherogenic processes, whereas downregulated proteins were involved in extracellular matrix organization and vascular smooth muscle cytoskeleton. Many of the identified proteins were linked to various "upstream regulators", among which TGFβ had the highest connections. Specifically, a total of 19 genes were commonly upregulated, and 30 genes were downregulated at the mRNA and protein levels. These genes were involved in vascular smooth muscle cell activity, for which enriched transcription factors were identified. This study deciphers altered pathways in atherosclerosis and identifies upstream regulators that could be candidate targets for treatment.

Psalms of the Faithful: Luther’s Early Reading of the Psalter in Canonical Context by Brian T. German

Reviewed by: Psalms of the Faithful: Luther’s Early Reading of the Psalter in Canonical Context by Brian T. German Brooks Schramm Psalms of the Faithful: Luther’s Early Reading of the Psalter in Canonical Context. By Brian T. German. Studies in Historical and Systematic Theology. Bellingham, WA: Lexham Press, 2017. 217 pp. This book is the product of the author’s doctoral work at Wycliffe College, University of Toronto, under Christopher R. Seitz, who himself has been one of the most prolific and influential students of Brevard S. Childs. The influence of Childs’s original and controversial hermeneutical work in articulating a canonical approach to the Christian Old Testament and Seitz’s appropriation and development of that work are everywhere evident in German’s penetrating new study of Luther’s Dictata super Psalterium (1513–1515). Taking his bearings from James Samuel Preus and Scott H. Hendrix, chiefly in terms of their understanding of Luther’s use of “faithful synagogue” (fidelis synagoga) in the Dictata, German pursues the argument that the generally acknowledged difference in character between the latter part of the Dictata and its earlier portion is attributable—and traceable—to the coercion of the canonical shape of the Psalter itself on Luther as he lectured his way through it in sequential fashion over a two-year period. Chapter 1, “A Fresh Look at Luther,” serves both to sketch the structure and argument of the book as well as to introduce the reader to recent research in contemporary Psalms scholarship that has begun to take strong interest in the final form or canonical shape of the five-book Psalter. It is this latter that gives the book its distinctive methodological character, for in addition to reading Luther’s [End Page 120] Psalms interpretation in light of the influence of Augustine (and Cassiodorus), German is also examining how an aspect of modern critical biblical study can “expand our knowledge of a premodern series of psalm lectures” (21). Chapter 2, “The Origins of the Faithful Synagogue,” focuses on what is the turning-point in the Dictata and in the canonical structure of the Psalter itself, namely, Book III (Pss. 73–89). Analysis of Luther’s treatment of the Asaphite Psalms (Pss. 73–83) in particular, where traditional exegesis had tended to identify the name Asaph with the synagogue, serves to demonstrate that this is the precise point where the concept of “faithful synagogue” becomes both prominent in the lecture series as well as distinctive over against Augustine and Cassiodorus. Chapter 3, “Joining the Faithful Synagogue,” focuses on Luther’s treatment of the remaining Psalms in Book III and in Book IV (Pss. 90–106), showing how the concept of “faithful synagogue” as developed in the Asaphite corpus now exercises hermeneutical influence on Luther’s interpretation of immediately succeeding Psalms. In Chapter 4, “Reading Scripture with the Faithful Synagogue,” German turns to Book V (Pss. 107–150) and explicates “the most immediate hermeneutical implications of Luther’s increasing preoccupation with the Old Testament perspective” (26, 185), the most significant of which is that the interpretive lens of the “faithful synagogue” eventuates for Luther in “a reappraisal of the literal sense of Scripture” (186). In the concluding Chapter 5, “What Does This Mean?,” German summarizes the arguments of the book and states his central claim: “[. . .] the second half of Martin Luther’s Dictata super Psalterium exhibits a noticeably different character than the first half because of (emphasis added) the profound effect that the canonical shape of the Hebrew Psalter had on Luther’s journey from Psalm 1 to Psalm 150” (191). This book is a serious piece of scholarship. Combining methodological sophistication with absolute lucidity, German demonstrates that interaction between critical and pre-critical approaches to the biblical text can yield fresh and compelling insights. Highly recommended for both scholars and motivated students alike. [End Page 121] Brooks Schramm United Lutheran Seminary Gettysburg, Pennsylvania Copyright © 2019 Johns Hopkins University Press and Lutheran Quarterly, Inc

Stimulus- and Response-locked Posterior Contralateral Negativity Bisect Cognitive Operations in Visual Search.

We explored the flow of information during visual search by examining activity indexing visual attention (N2pc) and the subsequent processing of the selected objects in visual short-term memory (SPCN) time-locked to stimulus presentation and to the motor response. We measured event-related activity at posterior sites (PO7/PO8) for 96 participants during a simple visual search task. A response-locked posterior contralateral negativity (RLpcN) was observed with a scalp distribution similar to that of the N2pc and SPCN. The RLpcN was compared with the stimulus-locked activity (N2pc and SPCN) across experimental manipulations (targets were either closer or farther from fixation in visual space, and the response was either more frequent [75%] or less frequent [25%]) and across response speeds (EEG data were separated into tertiles by RT both within-subjects and between-subjects). The leading edge and early portion of the RLpcN appeared to reflect the initial deployment of attention (N2pc), whereas the later portion (up to peak amplitude) reflected subsequent processing of visual information (SPCN). SPCN and RLpcN also had similar modulations in amplitude for both analyses. Moreover, whereas very small N2pc and SPCN onset latency differences were observed when data were separated into tertiles by RT, there were large onset differences for the RLpcN, with earlier RLpcN onsets for longer RTs, suggesting that RT variance is in large determined by processing after the initial deployment of attention. The results show how we can bisect processing responsible for variations in RT relative to the onset of visual spatial attention.

Determinants of Peripheral Pulse Pressure and Pulse Pressure Amplification

ObjectivePeripheral (e.g. brachial) Pulse Pressure (Ppp) exceeds central pulse pressure (Cpp) corresponding to the first (Cpp1) or second (Cpp2) peaks in the central waveform. This pulse pressure amplification, attributed to propagation of the pulse wave from aorta to periphery and influence of reflection in the periphery, is measured as Ppp/Cpp2 (when Cpp2 > Cpp1). We examined whether the haemodynamic determinant of Ppp relates more closely to Cpp1 rather than Cpp2.MethodsWe examined the theoretical influence of change in morphology of central aortic waveform on peripheral waveform when applying a reverse transfer function to the aortic waveform. Secondly, we examined the relationship between central and peripheral waveforms during modulation of central pressure with nitroglycerine (GTN). Central pressures were obtained during cardiac atheterization with a Millar catheter placed in the proximal aortic root in patients with non-critical coronary artery disease (n = 15) at baseline and after GTN. The digital arterial pulse was acquired simultaneously with a servo-controlled finger cuff.ResultsIn theoretical analysis, Ppp was sensitive only to the portion of the waveform up to the time of Cpp1. Similar results were observed with GTN, which had no significant effect on Cpp1 (38.7 ± 2.0 and 37.1 ± 2.5 mmHg at baseline and after GTN respectively, P = 0.36) nor on Ppp (70.2 ± 5.0 and 69.2 ± 4.7 mmHg at baseline and after GTN respectively, P = 0.47) but reduced Cpp2 by 17.0 ±1.8 mmHg (P < 0.001).ConclusionsThese results suggest that peripheral pulse pressure is determined by the early systolic portion of the central aortic pressure waveform up to the time of Cpp1 and may be independent of Cpp2.

Cortical neural modulation by previous trial outcome differentiates fast- from slow-learning rats on a visuomotor directional choice task.

To better understand the neural cortical underpinnings that explain behavioral differences in learning rate, we recorded single-unit activity in primary motor (M1) and secondary motor (M2) areas while rats learned to perform a directional (left or right) operant visuomotor association task. Analysis of neural activity during the early portion of the cue period showed that neural modulation in the motor cortex was most strongly associated with two task factors: the previous trial outcome (success or error) and the current trial's directional choice (left or right). Furthermore, the fast learners, defined as those who had steeper learning curves and required fewer learning sessions to reach criterion performance, encoded the previous trial outcome factor more strongly than the directional choice factor. Conversely, the slow learners encoded directional choice more strongly than previous trial outcome. These differences in task factor encoding were observed in both the percentage of neurons and the neural modulation depth. These results suggest that fast learning is accompanied by a stronger component of previous trial outcome in the modulation representation present in motor cortex, which therefore may be a contributing factor to behavioral differences in learning rate. NEW & NOTEWORTHY We chronically recorded neural activity as rats learned a visuomotor directional choice task from a naive state. Learning rates varied. Single-unit neural modulation of two motor areas revealed that the fast learners encoded previous trial outcome more strongly than directional choice, whereas the reverse was true for slow learners. This finding provides novel evidence that rat learning rate is strongly correlated with the strength of neural modulation by previous trial outcome in motor cortex.

Productivity and diversity of annually harvested reconstructed prairie communities

AbstractBiofuel production from cellulosic feedstocks may increase during the next century. To be sustainable, this production should protect environmental quality and biodiversity. Fertilized mixed‐species prairie can deliver substantial quantities of cellulosic ethanol per unit land area with minimal losses of NO3‐N in drainage water, but the long‐term maintenance of biodiversity in such systems has been uncertain.We report how nitrogen, phosphorus, and potassium fertilizer application, precipitation, and time affected the species composition and productivity of reconstructed prairie communities harvested annually as biofuel feedstocks over a 9‐year period.Results indicated that both precipitation and fertilizer application drove above‐ground biomass production, with the greatest response to fertilizer occurring in wetter than average years. Fertilization reduced species richness, but increased species evenness. Consequently, Simpson's diversity index did not differ between the fertilized and unfertilized communities, though it declined in both communities over time.A total of 59 plant species was recorded, with eight of them explaining most of the differences in vegetation cover between the fertilized and unfertilized treatments. After 9 years, the high fertility community was dominated by the C4 grassAndropogon gerardii,the C3 grassElymus canadensis, and the non‐leguminous forbsHeliopsis helianthoides,Helianthus maximiliani, andMonarda fistulosa, whereas the low fertility community was dominated by the C4 grassesA. gerardiiandSorghastrum nutans, the C3 grassE. canadensis, and the non‐leguminous forbM. fistulosa. Fertilization increased the abundance of flowering forbs available to pollinators in the early, middle and late portions of the growing season.Synthesis and applications. Results of our study suggest that maintenance of reasonably high levels of productivity and biodiversity are possible in fertilized prairie communities harvested annually for bioenergy, with plant cover more evenly distributed among different functional groups. In the future, if policy and markets favour biofuels and better delivery of ecosystem services from harvested land, prairie‐based feedstocks could become part of a renewable energy portfolio that fosters biodiversity and contributes to the provision of floral resources for pollinators.

A novel role for Tamm-Horsfall protein (uromodulin) in the renal tubule

Tamm-Horsfall protein (THP)/uromodulin, the most abundant urinary protein, is produced in the thick ascending limb of the loop of Henle. Besides immunological functions, it has regulatory impact on ion transport and volume regulation. It had been debated whether the distal convoluted tubule is a source for THP as well. Novel results suggest that in its early portions, THP synthesis affects adaptive plasticity of the epithelium, stabilizes calcium homeostasis, and activates the thiazide-sensitive Na+,Cl--cotransporter.

Short-term, not long-term, average spectra of preceding sentences bias consonant categorization

Phoneme perception is influenced by spectral properties of surrounding sounds. For example, listeners perceive /g/ (lower F3 onset) more often after sentences filtered to emphasize high-F3 frequencies, and perceive /d/ (higher F3 onset) more often after sentences filtered to emphasize low-F3 frequencies. These biases are known as spectral contrast effects (SCEs). Much of this work examined differences between long-term average spectra (LTAS) of preceding sounds and target phonemes. Stilp and Assgari (2018 ASA) revealed that spectra of the last 500 ms of precursor sentences, not the entire LTAS, predicted biases in consonant categorization. Here, the influences of Early (before the last 500 ms) versus Late (last 500 ms) portions of precursor sentences on subsequent consonant categorization were compared. Sentences emphasized different frequency regions in each temporal window (Early = low-F3 emphasis, Late = high-F3 emphasis, and vice versa) naturally or via filtering. Entire-sentence LTASes predicted that SCEs would not bias consonant categorization, but instead responses were biased by the spectrum of the Late window. This was replicated when the Early window did not emphasize either frequency region but the Late window did. Results endorse closer consideration of patterns of spectral energy over time in preceding sounds, not just their LTAS.