VARIATION IN PLANT WATER USE, GROWTH, AND WATER-USE EFFICIENCY OF PLANTED MIXTURES AND MONOCULTURES: TOWARD PROPER SPECIES SELECTION FOR REFORESTATION EFFORTS IN THE SEASONALLY DRY TROPICS

In recent years, there has been a trend towards reforesting previously degraded areas by planting trees. While plantations offer an opportunity to restore ecosystem functions and diversity, most reforested plantations currently consist of monocultures, or single-species systems. Originally planted to provide wood for both global and regional markets, monocultures provide only a few goods and services and reduce plant biodiversity in comparison to multi-species systems, like forests. An alternative to the current plantation design is planting mixed species systems. Beyond diversifying a plantation, mixed species stands provide an opportunity to enhance ecosystem services that include non-timber forest products, carbon sequestration, and increased soil fertility. There is also evidence that mixed species stands tend to be more resilient to disturbances and climate change than monocultures. Both anthropogenic and environmental stresses put pressure on tropical forests. Plantations, however, provide a means of decreasing anthropogenic pressures on forests by providing timber products, among other goods and services. Despite the increase in popularity of plantations, research still does not fully understand how certain plantation species might affect resource use (i.e., nutrient abundance and water quantity). While a growing body of research has begun to include studies on how resource use might change when species are planted in monocultures and mixtures, additional research is needed in areas where soils are severely degraded. In the seasonally dry tropics of Panama, how species in monocultures and simplified mixed species systems respond to changes in water availability is also of importance because survival of the dry season is central to the longevity of the species and the stand. In Panama, the Agua Salud Project offers a unique opportunity to explore the dynamics of reforested areas that were previously degraded, with a specific emphasis is on understanding ecosystem services provided by forests and how these services change with land use change. Like most deforested areas, the Agua Salud Project plantations are planted on sub-marginal lands with poor soil. In 2008, native species plantations were established in two blocks which had previously been cleared 40 years before. The spatial arrangement of the species in the mixed species stands allows for isolation of interactions between species so we can test both interspecific interactions and how species strategies vary in monocultures and simplified mixed systems. Understanding the link between species diversity and water use dynamics is a crucial first step toward proper selection of species that balance the tradeoffs between growth and transpiration. In addition to selecting species that regulate water well in this region, choosing species that are economically valuable in such a way that they can compete financially with the commonly planted non-native Tectona grandis (teak), is necessary to transition away from planting non-natives and towards planting native species. In addition to ecophysiological characteristics of these species when planted in different combinations, we provide information about how the native species will compete financially against teak and whether mixtures or monocultures are more lucrative operationally

Toward understanding the economic and ecological outcomes of selection silviculture on a northern hardwood forest

Single-tree selection (STS) and small-group selection (SGS) silviculture are widely used in the northeastern United States, but questions remain regarding the economic and ecological outcomes of these systems. To assess harvest treatment effects on northern hardwood forests, we examined an unmanaged stand (UNM) and STS and SGS managed stands within the Bartlett Experimental Forest of New Hampshire. For an economic perspective, grade and standing tree values were our metrics to evaluate changes in timber quality. After 60 years of management, the percentage of higher graded trees increased slightly for both the SGS and STS managed stands. However, current data suggests no statistically significant differences in the standing tree value among the UNM, STS, and SGS. For an ecological perspective, density and volume of downed woody debris (DWD) was used for assessing structural heterogeneity. SGS and UNM had the greatest volume and density of DWD

Impact of foot progression angle modification on plantar loading in individuals with diabetes mellitus and peripheral neuropathy

AIMS: To determine if participants can reduce foot progression angle (FPA), and if FPA reduction decreases regional plantar stresses and forces in individuals with diabetes. METHODS: DESIGN: Three-group cross-sectional design with repeated measures. SUBJECTS: twenty-eight participants either with diabetes mellitus (DM), diabetes and peripheral neuropathy with (DMPN+NPU) or without a prior history of ulceration (DMPN−NPU) were studied. INTERVENTION: Participants were first instructed to walk over a 3.6 m walkway at their preferred FPA, and then to walk with their foot aligned parallel with the line of gait progression at their self-selected speed. Dynamic plantar kinetics in six masked regions were collected using an EMED-st-P-2 pedobarograph. MAIN MEASURES: Primary outcome measures were FPA, peak plantar pressure (PPP), and force-time integral (FTI). A repeated measures ANOVA was conducted to determine group differences in FPA for both walking conditions. Regional differences in PPPs and FTIs between preferred and corrected walking conditions were analyzed using repeated measures ANCOVA. RESULTS: Participants showed a reduction in FPA magnitude on the ‘Involved’ foot between the preferred and corrected walking conditions (p<0.01). There were no differences in PPPs or FTIs in any mask between walking conditions (p>0.05). CONCLUSION: Results from this investigation offer important evidence that people with diabetes can modify their FPA with a simple intervention of visual and verbal cueing. Future research should examine if gait retraining strategies in regular footwear more effectively offload areas of elevated regional plantar stresses and forces in adults with diabetes mellitus and peripheral neuropathy

Intermuscular Adipose Tissue Is Muscle Specific and Associated with Poor Functional Performance

Purpose. People with obesity, diabetes, and peripheral neuropathy have high levels of intermuscular adipose tissue (IMAT) volume which has been inversely related to physical function. We determined if IMAT is muscle specific, if calf IMAT is different between a healthy obese group (HO), a group with diabetes mellitus (D), and a group with diabetes mellitus and peripheral neuropathy (DN), and if IMAT volume or the ratio of IMAT/muscle volume is related to physical function in these groups. Methods. 10 healthy obese people, 11 with type 2 diabetes, 24 with diabetes and peripheral neuropathy, had assessments of muscle morphology, physical function and muscle performance. Results. The gastrocnemius muscle had a higher ratio of IMAT/muscle volume than any other muscle or compartment. There were no differences between groups in calf muscle or IMAT volumes. Calf IMAT was inversely related to physical performance on the 6-minute walk test (r = −0.47) and physical performance test (r = −0.36). IMAT/muscle volume was inversely related to physical performance (PPT, r = −0.44; 6 MW r = −0.48; stair power, r = −0.30). Conclusions. IMAT accumulation varies in calf muscles, is highest in the gastrocnemius muscle, and is associated with poor physical performance

Pain Scores Are Not Predictive of Pain Medication Utilization

Objective. To compare Visual Analogue Scale (VAS) scores with overall postoperative pain medication requirements including cumulative dose and patterns of medication utilization and to determine whether VAS scores predict pain medication utilization. Methods. VAS scores and pain medication data were collected from participants in a randomized trial of the utility of phenazopyridine for improved pain control following gynecologic surgery. Results. The mean age of the 219 participants was 54 (range19 to 94). We did not detect any association between VAS and pain medication utilization for patient-controlled anesthesia (PCA) or RN administered (intravenous or oral) medications. We also did not detect any association between the number of VAS scores recorded and mean pain scores. Conclusion. Postoperative VAS scores do not predict pain medication use in catheterized women inpatients following gynecologic surgery. Increased pain severity, as reflected by higher VAS scores, is not associated with an increase in pain assessment. Our findings suggest that VAS scores are of limited utility for optimal pain control. Alternative or complimentary methods may improve pain management

Reliability of clinically relevant 3D foot bone angles from quantitative computed tomography

BACKGROUND: Surgical treatment and clinical management of foot pathology requires accurate, reliable assessment of foot deformities. Foot and ankle deformities are multi-planar and therefore difficult to quantify by standard radiographs. Three-dimensional (3D) imaging modalities have been used to define bone orientations using inertial axes based on bone shape, but these inertial axes can fail to mimic established bone angles used in orthopaedics and clinical biomechanics. To provide improved clinical relevance of 3D bone angles, we developed techniques to define bone axes using landmarks on quantitative computed tomography (QCT) bone surface meshes. We aimed to assess measurement precision of landmark-based, 3D bone-to-bone orientations of hind foot and lesser tarsal bones for expert raters and a template-based automated method. METHODS: Two raters completed two repetitions each for twenty feet (10 right, 10 left), placing anatomic landmarks on the surfaces of calcaneus, talus, cuboid, and navicular. Landmarks were also recorded using the automated, template-based method. For each method, 3D bone axes were computed from landmark positions, and Cardan sequences produced sagittal, frontal, and transverse plane angles of bone-to-bone orientations. Angular reliability was assessed using intraclass correlation coefficients (ICCs) and the root mean square standard deviation (RMS-SD) for intra-rater and inter-rater precision, and rater versus automated agreement. RESULTS: Intra- and inter-rater ICCs were generally high (≥ 0.80), and the ICCs for each rater compared to the automated method were similarly high. RMS-SD intra-rater precision ranged from 1.4 to 3.6° and 2.4 to 6.1°, respectively, for the two raters, which compares favorably to uni-planar radiographic precision. Greatest variability was in Navicular: Talus sagittal plane angle and Cuboid: Calcaneus frontal plane angle. Precision of the automated, atlas-based template method versus the raters was comparable to each rater’s internal precision. CONCLUSIONS: Intra- and inter-rater precision suggest that the landmark-based methods have adequate test-retest reliability for 3D assessment of foot deformities. Agreement of the automated, atlas-based method with the expert raters suggests that the automated method is a valid, time-saving technique for foot deformity assessment. These methods have the potential to improve diagnosis of foot and ankle pathologies by allowing multi-planar quantification of deformities

A randomised feasibility study of serial magnetic resonance imaging to reduce treatment times in Charcot neuroarthropathy in people with diabetes (CADOM): A protocol

Background Charcot neuroarthropathy is a complication of peripheral neuropathy associated with diabetes which most frequently affects the lower limb. It can cause fractures and dislocations within the foot, which may progress to deformity and ulceration. Recommended treatment is immobilisation and offloading, with a below knee non-removable cast or boot. Duration of treatment varies from six months to more than one year. Small observational studies suggest that repeated assessment with Magnetic Resonance Imaging improves decision making about when to stop treatment, but this has not been tested in clinical trials. This study aims to explore the feasibility of using serial Magnetic Resonance Imaging without contrast in the monitoring of Charcot neuroarthropathy to reduce duration of immobilisation of the foot. A nested qualitative study aims to explore participants’ lived experience of Charcot neuroarthropathy and of taking part in the feasibility study. Methods We will undertake a two arm, open study, and randomise 60 people with a suspected or confirmed diagnosis of Charcot neuroarthropathy from five NHS, secondary care multidisciplinary Diabetic Foot Clinics across England. Participants will be randomised 1:1 to receive Magnetic Resonance Imaging at baseline and remission up to 12 months, with repeated foot temperature measurements and x-rays (standard care plus), or standard care plus with additional three-monthly Magnetic Resonance Imaging until remission up to 12 months (intervention). Time to confirmed remission of Charcot neuroarthropathy with off-loading treatment (days) and its variance will be used to inform sample size in a full-scale trial. We will look for opportunities to improve the protocols for monitoring techniques and the clinical, patient centred, and health economic measures used in a future study. For the nested qualitative study, we will invite a purposive sample of 10-14 people able to offer maximally varying experiences from the feasibility study to take part in semi-structured interviews to be analysed using thematic analysis. Discussion The study will inform the decision whether to proceed to a full-scale trial. It will also allow deeper understanding of the lived experience of Charcot neuroarthropathy, and factors that contribute to engagement in management and contribute to the development of more effective patient centred strategies. Trial registration ISRCTN, ISRCTN, 74101606. Registered on 6 November 2017, http://www.isrctn.com/ISRCTN74101606?q=CADom&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-searc