Climate control of terrestrial carbon exchange across biomes and continents

Peer reviewe

The Carbon Cycle of a Semi-arid Grass System, Bromus tectorum

Understanding the carbon cycle of major ecosystems is important in predicting feedback responses of the terrestrial biosphere to climate change. Bromus tectorum dominated ecosystems currently cover 7% of the Great Basin and represents a major land cover type for the region. This study looked at the carbon cycle of a near monoculture field of B. tectorum in southeastern Idaho, USA. A major portion of the study was dedicated to measurement validation because of the disagreement among techniques used to measure net ecosystem exchange (NEE) of CO2 between the atmosphere and terrestrial ecosystems . NEE, net photosynthesis, and canopy and soil respiration were quantified for the B. tectorum stand using multiple methods. This allowed for comparisons among measurement techniques and permitted the calculation of a best estimate of NEE. The study found that the eddy covariance technique underestimated NEE at night for the B. tectorum stand and the magnitude of underestimation increased with increasing leaf area index of the plant canopy. Annual NEE estimated by eddy covariance for the year 2005 was over four times lower than the best estimate of -80 g C m-2 yr-1 determined by a combination of methods. Implications are that many studies currently underestimate NEE and productive systems underestimate NEE more than less productive systems

Ansattes holdninger til robotisering av arbeidsoppgaver : en casestudie av ansattes holdninger til å ta i bruk Robotic Process Automation i Bergen kommune

Denne masterutredningen ser på ansattes holdninger til Robotic Process Automation (RPA), og hvilke implikasjoner dette har for implementering av RPA. For å undersøke dette har vi tatt utgangspunkt i en endringsmodell, hvor oppfatninger av ulike elementer ved endringens innhold, endringsprosessen, og endringsledelse er med på å forme ansattes holdninger til endringen. Vi har undersøkt dette ved å intervjue ledere og ansatte i LRS i Bergen kommune. Våre funn indikerer at ansatte i LRS hovedsakelig har positive holdninger til å ta i bruk RPA. Årsaken til dette er at ansatte ser hvilke fordeler teknologien kan gi, samt at en ikke frykter å bli erstattet av robotene. Dette henger sammen med en allerede stor arbeidsbelastning, og at teknologien også vil kunne generere nye oppgaver. Imidlertid fant vi også at enkelte ansatte har vært skeptiske til å ta i bruk RPA og har kjent på usikkerhet, noe som har resultert i mer negative holdninger. Samtidig har vi sett at kommunikasjon og involvering har hatt en betydning for ansattes engasjement rundt endringen. Manglende informasjon ser ut til å ha medført at positive ansatte mistet noe av interessen for prosjektet, samtidig som usikkerheten hos negative ansatte vedvarte. Etterhvert som ansatte har fått mer kjennskap til RPA, samt at ledelsen av prosessene har blitt bedre, har negative holdninger utviklet seg i mer positiv retning. Dermed har også elementer ved endringsprosessen og endringsledelse hatt betydning for ansattes holdninger til å ta i bruk RPA, selv om holdningene hovedsakelig virker å være basert på oppfatninger av endringens innhold. Basert på studiens funn har vi fremhevet fem elementer som er sentrale for at ansatte skal danne positive holdninger til RPA, og som følgelig bør fokuseres på av organisasjoner som skal ta i bruk teknologien. Det vil være viktig å kommunisere og informere tilstrekkelig gjennom hele prosessen, samt sørge for bred involvering av ansatte. Samtidig vil arbeidsmengde og tidsperspektiv være faktorer som kan virke inn på implementeringen av RPA. I tillegg vil det være hensiktsmessig å ha engasjerte og kunnskapsrike ledere, som kan planlegge og gjennomføre endringen på en effektiv måte, samt ivareta ansattes behov

Ansattes holdninger til robotisering av arbeidsoppgaver : en casestudie av ansattes holdninger til å ta i bruk Robotic Process Automation i Bergen kommune

Denne masterutredningen ser på ansattes holdninger til Robotic Process Automation (RPA), og hvilke implikasjoner dette har for implementering av RPA. For å undersøke dette har vi tatt utgangspunkt i en endringsmodell, hvor oppfatninger av ulike elementer ved endringens innhold, endringsprosessen, og endringsledelse er med på å forme ansattes holdninger til endringen. Vi har undersøkt dette ved å intervjue ledere og ansatte i LRS i Bergen kommune. Våre funn indikerer at ansatte i LRS hovedsakelig har positive holdninger til å ta i bruk RPA. Årsaken til dette er at ansatte ser hvilke fordeler teknologien kan gi, samt at en ikke frykter å bli erstattet av robotene. Dette henger sammen med en allerede stor arbeidsbelastning, og at teknologien også vil kunne generere nye oppgaver. Imidlertid fant vi også at enkelte ansatte har vært skeptiske til å ta i bruk RPA og har kjent på usikkerhet, noe som har resultert i mer negative holdninger. Samtidig har vi sett at kommunikasjon og involvering har hatt en betydning for ansattes engasjement rundt endringen. Manglende informasjon ser ut til å ha medført at positive ansatte mistet noe av interessen for prosjektet, samtidig som usikkerheten hos negative ansatte vedvarte. Etterhvert som ansatte har fått mer kjennskap til RPA, samt at ledelsen av prosessene har blitt bedre, har negative holdninger utviklet seg i mer positiv retning. Dermed har også elementer ved endringsprosessen og endringsledelse hatt betydning for ansattes holdninger til å ta i bruk RPA, selv om holdningene hovedsakelig virker å være basert på oppfatninger av endringens innhold. Basert på studiens funn har vi fremhevet fem elementer som er sentrale for at ansatte skal danne positive holdninger til RPA, og som følgelig bør fokuseres på av organisasjoner som skal ta i bruk teknologien. Det vil være viktig å kommunisere og informere tilstrekkelig gjennom hele prosessen, samt sørge for bred involvering av ansatte. Samtidig vil arbeidsmengde og tidsperspektiv være faktorer som kan virke inn på implementeringen av RPA. I tillegg vil det være hensiktsmessig å ha engasjerte og kunnskapsrike ledere, som kan planlegge og gjennomføre endringen på en effektiv måte, samt ivareta ansattes behov.nhhma

Normative Quadriceps and Hamstring Muscle Strength Values for Female, Healthy, Elite Handball and Football Players

This study presents normative values for isokinetic knee extension and flexion muscle strength tests in 350 elite, female, handball (n = 150) and football (n = 200) players. Isokinetic concentric muscle strength tests at 60°·sec−1 were recorded bilaterally using a dynamometer. Peak torque (in Newton meter [N·m]), body mass normalized peak torque (N·m·kg−1), and hamstring to quadriceps ratio (H:Q ratio) for dominant and nondominant legs were recorded. The female elite players were 20.9 ± 4.0 years, started playing at the elite level at the age of 18.2 ± 2.7 years, with a mean of 9.7 ± 2.2 hours of weekly in-season training. Handball players demonstrated greater quadriceps muscle strength compared with football players (11.0%) (p < 0.001), also when normalized to body mass (4.1%) (p = 0.012), but not for weight-adjusted hamstring muscle strength. The H:Q ratio was higher on the dominant compared with the nondominant leg for handball players only (p = 0.012).The H:Q ratio was significantly lower for handball players (0.58) compared with football players (0.60) (p < 0.02). These normative values for isokinetic knee extension and flexion torques of healthy, elite, female handball and football players can be used to set rehabilitation goals for muscle strength after injury and enable comparison with uninjured legs. Significantly greater quadriceps muscle strength was found for handball players compared with football players, also when normalized to body mass

Assessing implementation, limited efficacy, and acceptability of the BEAST tool : A rehabilitation and return-to-sport decision tool for nonprofessional athletes with anterior cruciate ligament reconstruction

OBJECTIVES: To assess the implementation, limited efficacy, and acceptability of the BEAST (better and safer return to sport) tool - a rehabilitation and return-to-sport (RTS) decision tool after anterior cruciate ligament reconstruction (ACLR) in nonprofessional athletes. DESIGN: Prospective cohort. PARTICIPANTS: 43 nonprofessional pivoting sport athletes with ACLR. MAIN OUTCOME: Clinician- and athlete-experienced implementation challenges (implementation), changes in quadriceps power, side hop and triple hop performance from 6 to 8 months after ACLR (limited efficacy), athletes' beliefs about the individual rehabilitation and RTS plans produced by the BEAST tool (acceptability). RESULTS: The BEAST tool was developed and then implemented as planned for 39/43 (91%) athletes. Hop and quadriceps power performance improved significantly, with the largest improvement in involved quadriceps power (standardised response mean 1.4, 95% CI:1.1-1.8). Athletes believed the rehabilitation and RTS plan would facilitate RTS (8.2 [SD: 2.0]) and reduce injury risk (8.3 [SD: 1.2]; 0 = not likely at all, 10 = extremely likely). CONCLUSION: The BEAST tool was implemented with few challenges and adjustments were rarely necessary. Athletes had large improvements in quadriceps power and hop performance on the involved leg. Athletes believed that the individual rehabilitation and RTS plans produced by the tool would facilitate RTS and reduce injury risk

prior to return to sports after ACL reconstruction

Muscle strength and hop performance criteri

Knee function and prevalence of knee osteoarthritis after anterior cruciate ligament reconstruction : a prospective study with 10 to 15 years of follow-up

BACKGROUND: Few prospective long-term studies of more than 10 years have reported changes in knee function and radiologic outcomes after anterior cruciate ligament (ACL) reconstruction. PURPOSE: To examine changes in knee function from 6 months to 10 to 15 years after ACL reconstruction and to compare knee function outcomes over time for subjects with isolated ACL injury with those with combined ACL and meniscal injury and/or chondral lesion. Furthermore, the aim was to compare the prevalence of radiographic and symptomatic radiographic knee osteoarthritis between subjects with isolated ACL injuries and those with combined ACL and meniscal and/or chondral lesions 10 to 15 years after ACL reconstruction. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Follow-up evaluations were performed on 221 subjects at 6 months, 1 year, 2 years, and 10 to 15 years after ACL reconstruction with bone-patellar tendon-bone autograft. Outcome measurements were KT-1000 arthrometer, Lachman and pivot shift tests, Cincinnati knee score, isokinetic muscle strength tests, hop tests, visual analog scale for pain, Tegner activity scale, and the Kellgren and Lawrence classification. RESULTS: One hundred eighty-one subjects (82%) were evaluated at the 10- to 15-year follow-up. A significant improvement over time was revealed for all prospective outcomes of knee function. No significant differences in knee function over time were detected between the isolated and combined injury groups. Subjects with combined injury had significantly higher prevalence of radiographic knee osteoarthritis compared with those with isolated injury (80% and 62%, P = .008), but no significant group differences were shown for symptomatic radiographic knee osteoarthritis (46% and 32%, P = .053). CONCLUSION: An overall improvement in knee function outcomes was detected from 6 months to 10 to 15 years after ACL reconstruction for both those with isolated and combined ACL injury, but significantly higher prevalence of radiographic knee osteoarthritis was found for those with combined injuries

Variation in peak growing season net ecosystem production across the Canadian arctic

Tundra ecosystems store vast amounts of soil organic carbon, which may be sensitive to climatic change. Net ecosystem production, NEP, is the net exchange of carbon dioxide (CO2) between landscapes and the atmosphere, and represents the balance between CO2 uptake by photosynthesis and release by decomposition and autotrophic respiration. Here we examine CO 2 exchange across seven sites in the Canadian low and high Arctic during the peak growing season (July) in summer 2008. All sites were net sinks for atmospheric CO2 (NEP ranged from 5 to 67 g C m-2), with low Arctic sites being substantially larger CO2 sinks. The spatial difference in NEP between low and high Arctic sites was determined more by CO2 uptake via gross ecosystem production than by CO2 release via ecosystem respiration. Maximum gross ecosystem production at the low Arctic sites (average 8.6 μmol m-2 s-1) was about 4 times larger than for high Arctic sites (average 2.4 μmol m-2 s-1). NEP decreased with increasing temperature at all low Arctic sites, driven largely by the ecosystem respiration response. No consistent temperature response was found for the high Arctic sites. The results of this study clearly indicate there are large differences in tundra CO2 exchange between high and low Arctic environments and this difference should be a central consideration in studies of Arctic carbon balance and climate change