Instability of the Ekman Spiral with Applications to the Planetary Boundary Layers

Spiral boundary layer instability applied to planetary boundary layer

Predictors of discordance among Chilean families

Parent-youth agreement on parental behaviors can characterize effective parenting. Although discordance in families may be developmentally salient and harmful to youth outcomes, predictors of discordance have been understudied, and existing research in this field has been mostly limited to North American samples. This paper addressed this literature gap by using data from a community-based study of Chilean adolescents. Analysis was based on 1,068 adolescents in Santiago, Chile. The dependent variable was discordance which was measured by the difference between parent and youth’s assessment of parental monitoring. Major independent variables for this study were selected based on previous research findings that underscore youth’s developmental factors, positive parental and familial factors and demographic factors. Descriptive and multivariate analyses were conducted to examine the prevalence and associations between youth, parental and familial measures with parent-youth discordance. There was a sizable level of discordance between parent and youth’s report of parental monitoring. Youth’s gender and externalizing behavior were significant predictors of discordance. Warm parenting and family involvement were met with decreases in discordance. The negative interaction coefficients between parental warmth and youth’s gender indicated that positive parental and familial measures have a greater effect on reducing parent-youth discordance among male youths. Results support the significance of positive family interactions in healthy family dynamics. Findings from this study inform the importance of services and interventions for families that aim to reduce youth’s problem behavior and to create a warm and interactive family environment.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4181713/Accepted manuscrip

The mission oriented terminal area simulation facility

The Mission Oriented Terminal Area Simulation (MOTAS) was developed to provide an ATC environment in which flight management and flight operations research studies can be conducted with a high degree of realism. This facility provides a flexible and comprehensive simulation of the airborne, ground-based and communication aspects of the airport terminal area environment. Major elements of the simulation are: an airport terminal area environment model, two air traffic controller stations, several aircraft models and simulator cockpits, four pseudo pilot stations, and a realistic air-ground communications network. MOTAS has been used for one study with the DC-9 simulator and a series of data link studies are planned in the near future

Blue light regenerates functional visual pigments in mammals through a retinyl-phospholipid intermediate.

The light absorbing chromophore in opsin visual pigments is the protonated Schiff base of 11-cis-retinaldehyde (11cRAL). Absorption of a photon isomerizes 11cRAL to all-trans-retinaldehyde (atRAL), briefly activating the pigment before it dissociates. Light sensitivity is restored when apo-opsin combines with another 11cRAL to form a new visual pigment. Conversion of atRAL to 11cRAL is carried out by enzyme pathways in neighboring cells. Here we show that blue (450-nm) light converts atRAL specifically to 11cRAL through a retinyl-phospholipid intermediate in photoreceptor membranes. The quantum efficiency of this photoconversion is similar to rhodopsin. Photoreceptor membranes synthesize 11cRAL chromophore faster under blue light than in darkness. Live mice regenerate rhodopsin more rapidly in blue light. Finally, whole retinas and isolated cone cells show increased photosensitivity following exposure to blue light. These results indicate that light contributes to visual-pigment renewal in mammalian rods and cones through a non-enzymatic process involving retinyl-phospholipids.It is currently thought that visual pigments in vertebrate photoreceptors are regenerated exclusively through enzymatic cycles. Here the authors show that mammalian photoreceptors also regenerate opsin pigments in light through photoisomerization of N-ret-PE (N-retinylidene-phosphatidylethanolamine

Bottom-up Drivers of Primary Producers and Predator Populations in Oregon Streams

Humans have drastically altered the physical habitat and food web structure of stream ecosystems. Two major impacts humans have had on Pacific Northwest streams are modification of streamside forests (as a result of agriculture, land development, and timber harvest), and declines in the return of wild anadromous salmon to headwater ecosystems (due to a range of habitat degradation, dams, harvest, and hatcheries). Riparian forest impacts have altered stream light dynamics, while the loss of salmon has led to declines in the delivery of nutrients from the ocean to streams. While the initial impacts of the modifications took place decades or even centuries ago, they can have lasting effects on stream ecosystems and food webs. This dissertation evaluates 1) influences of long-term recovery from historic riparian harvesting on stream light, habitat, and food webs, and 2) how reduced salmon subsidies to streams may be impacting stream productivity and food webs. Today most streams in the Pacific Northwest, and indeed across much of North America, have buffers of riparian forests that are regenerating from earlier land clearing. As stands recover, the trajectories of stand development will affect forest structure, which in turn affects stream light regimes. In the first half of my dissertation, I explore how stand age and structure relates to stream light availability and then how spatial differences and temporal changes in stream light influence stream food webs and higher trophic level biomass in headwater streams. In Chapter 2, I explore how stream light availability differs with the age and stage of riparian forests. I found that stream light flux was generally lower and less variable when bordered by second-growth forests compared to old-growth forests within a stream network and more broadly across forests west of the Cascade Mountains. Numerous studies have evaluated how large differences in light availability (e.g. fully forested compared to complete removal of riparian forests) influence stream food webs, but smaller differences in light availability, such as those found in Chapter 2, have received less consideration. In Chapter 3, I conducted surveys across 18 stream reaches and evaluated how variables associated with stream habitat, light, primary production, and macroinvertebrate biomass account for variability in the biomass of cutthroat trout and total vertebrates (fish and salamanders). Habitat metrics were not well correlated with higher trophic level biomass. In contrast, factors associated with resource availability — as regulated through bottom-up, autotrophic pathways — were closely related to the biomass of fish and other consumers. In Chapter 4, I quantified long-term responses of stream biota to the regeneration of riparian forests following clear-cut harvest. I resampled five stream reach pairs that were originally sampled in 1976 shortly after canopy removal. This initial survey showed that periphyton chlorophyll a, predatory invertebrate biomass, and cutthroat trout (Oncorhynchus clarkii clarkii) biomass were elevated in harvested reaches relative to reference reaches. After four decades of riparian regeneration, mean canopy openness, chlorophyll a, predatory invertebrate biomass, and cutthroat trout biomass declined in harvested reaches relative to paired old-growth reference reaches. Changes in canopy cover were consistent with biotic responses and suggest that changes in light availability as stands regenerated exerted control on biota through bottom-up pathways in these streams. While spatial and temporal light dynamics appear as important regulators of stream food webs in small forested streams of western Oregon, other factors may emerge as important constraints on food web productivity across stream networks in other regions. In the second half of my dissertation, I explore bottom-up drivers of fish production in a river network in eastern Oregon where canopies are more open than small western Oregon streams. I focus on nutrient and carbon subsides in this study as the loss of returning anadromous fish has been hypothesized as a key factor contributing to poor recovery of ESA-listed salmonids. In chapter 5, I evaluate network-scale spatial patterns of primary production, potential drivers of primary production, and juvenile salmonid abundance throughout two NE Oregon sub-basins. Primary production rates increased with watershed area and we were able to explain 72% of the variation in primary production across these basins using a combination of fixed-effects (e.g. light, nutrients, and temperature) and spatial autocorrelation. In contrast to other studies, juvenile salmonid abundance was greatest in cool headwaters where nutrient concentrations and rates of primary production were very low. To test the hypothesis that growth of juvenile salmonids and other biota in these low-productivity stream sections may be inhibited by the reduction of returning adult salmon and the associated loss of nutrient subsidies, I conducted a carcasses addition experiment in three locations of the Upper Grand Ronde River. In chapter 6, I focused on the responses of juvenile Chinook (Oncorhynchus tshawytsca) and steelhead (O. mykiss). Chinook and steelhead consumed an abundance of eggs and carcass tissue which resulted in greater growth rates and body condition of fish in treatment reaches relative to controls. To contextualize potential effects of increased growth on Chinook survival, I used an 18 year tagging and detection dataset to evaluate Chinook length-survival relationships. The positive association between length and survival suggests that actions resulting in larger Chinook lead to increased survival rates. In chapter 7, I evaluate carcass addition effects on the broader food web. Periphyton, aquatic invertebrates, and non-salmonid fish assimilated carcass nitrogen, but enrichment was far less than observed in juvenile salmonids. In contrast to salmonids, diet analysis and stable isotope patterns indicated that non-salmonids were not consuming eggs and carcass material, suggesting carcass nitrogen assimilation occurred through bottom-up pathways. These results suggest that salmon subsidies have the potential to broadly impact stream food webs in this region, but that species able to directly consume eggs and carcass material (i.e. juvenile salmonids) clearly benefit more from these subsidies

Deprescribing intervention activities mapped to guiding principles for use in general practice: a scoping review

Objective: To identify and characterise activities for deprescribing used in general practice and to map the identified activities to pioneering principles of deprescribing. Setting: Primary care. Data sources: Medline, EMBASE (Ovid), CINAHL, Australian New Zealand Clinical Trials Registry (ANZCTR), Clinicaltrials.gov, ISRCTN registry, OpenGrey, Annals of Family Medicine, BMC Family Practice, Family Practice and British Journal of General Practice (BJGP) from inception to the end of June 2021. Study: selection Included studies were original research (randomised controlled trial, quasi-experimental, cohort study, qualitative and case studies), protocol papers and protocol registrations. Data extraction: Screening and data extraction was completed by one reviewer; 10% of the studies were independently reviewed by a second reviewer. Coding of full-text articles in NVivo was conducted and mapped to five deprescribing principles. Results: Fifty studies were included. The most frequently used activities were identification of appropriate patients for deprescribing (76%), patient education (50%), general practitioners (GP) education (48%), and development and use of a tapering schedule (38%). Six activities did not align with the five deprescribing principles. As such, two principles (engage practice staff in education and appropriate identification of patients, and provide feedback to staff about deprescribing occurrences within the practice) were added. Conclusion: Activities and guiding principles for deprescribing should be paired together to provide an accessible and comprehensive guide to deprescribing by GPs. The addition of two principles suggests that practice staff and practice management teams may play an instrumental role in sustaining deprescribing processes within clinical practice. Future research is required to determine the most of effective activities to use within each principle and by whom

La observación sistemática de vecindarios: el caso de Chile y sus perspectivas para trabajo social

El estudio acerca de las características de los vecindarios y sus efectos sobre las personas ha llegado a ser un área de creciente atención por parte de investigadores de diversas disciplinas en países desarrollados. Aunque actualmente existen diversas metodologías para estudiar efectos del vecindario, una de las más utilizadas es la Observación Sistemática de Vecindarios –Systematic Social Observation SSO, en inglés—porque permite recolectar información acerca de diversas características del entorno físico, social, ambiental y económico de los vecindarios donde se aplica. El objetivo de este artículo es (i) dar a conocer sumariamente algunas investigaciones influyentes sobre efectos del vecindario en Estados Unidos, ii) describir cómo se diseñó e implementó la Observación Sistemática de Vecindarios en la ciudad de Santiago de Chile, iii) señalar algunos facilitadores y obstaculizadores de la implementación del proyecto y, finalmente iv) enunciar posibles contribuciones y limitaciones que esta metodología ofrecería al trabajo social en Chile.The study of neighborhood characteristics and their effects on individuals has become an area of increasing attention by scholars from various disciplines in developed countries. Although there are various methods to study neighborhoods and their impact on human populations, one of the most used is the Systematic Social Observation –Observación Sistemática de Vecindarios (OSV), in Spanish—because it allows the collection of information about various features of the physical, social, environmental and economic characteristics of neighborhoods. The purpose of this article is to (i) briefly present some research on neighborhood effects influential in the U.S., ii) describe how they Systematic Social Observation was designed and implemented in the city of Santiago, Chile, iii) discuss some facilitators and obstacles of the implementation process and, finally iv) list possible contributions and limitations this approach would offer the profession of social work in Chile.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4004073/Accepted manuscrip

Changing forests-changing streams: Riparian forest stand development and ecosystem function in temperate headwaters

Light availability influences temperature, primary production, nutrient dynamics, and secondary production in aquatic ecosystems. In forested freshwater ecosystems, shading by streamside (riparian) vegetation is a dominant control on light flux and represents an important interaction at the aquatic-terrestrial interface. Changes in forest structure over time, particularly tree mortality processes that gradually increase light penetration through maturing forest canopies, are likely to influence stream light fluxes and associated ecosystem functions. We provide a set of conceptual models describing how stream light dynamics change with the development of complex canopy structure and how changes in light availability are likely to affect stream ecosystem processes. Shortly after a stand-replacing event, light flux to the stream is high, but light fluxes decline as canopies reestablish and close. Tree density, the degree of understory growth, patterns of tree mortality, and small-scale disturbances interact as drivers of multiple pathways of forest structural development. Changes in canopy structure will, in turn, influence stream light, which is expected to impact primary production and stream nutrient dynamics as well as the amount of autochthonous carbon supporting aquatic food webs. Ultimately, these conceptual models stress the importance of recovery from historic forest disturbances as well as future forest change as important factors influencing the long-term trajectories of ecosystem processes in headwaters