Harvest Size Research Articles

A computational approach for crop production of organic vegetables

This paper deals with a vegetable production-planning problem in which a farmer has to simultaneously determine the crop rotations and harvest schedules for a number of vegetables in his farmlands. The crop rotation decisions include the determination of crop sequence, cropping times, and cropping size in each farmland. The harvest decisions include the collection times and harvesting size for each planted crop. By taking into account the growing season and technical-ecological constraints, this paper formulates a mixed integer linear programming model to develop vegetable production decisions for organic farmers. Due to the complexity of the model, we proposed a two-phase heuristic approach to solve the model. We applied the proposed model to analyze an organic farm in Taiwan. Computational results show that the proposed heuristic is superior to CPLEX in terms of solution quality and computational times for large scale problems. In addition, some sensitivity analyses were also conducted to evaluate the impact of parameters in the model.

Accuracy in the estimates of zucchini production related to the plot size and number of harvests

ABSTRACT: The productive variability in horticultural crops affects the planning and quality of the experiments, inflating the error and leading to wrong conclusions with low experimental accuracy and reliability. The objective of this study was to dimension the plot size and number of harvests that are necessary so that there is improvement in the accuracy of zucchini production. The production data used was the one from the uniformity trials where the basic units (BU) were identified with the number of crop row and were numbered according to the position inside the row. With the values of individual production, (fresh fruit biomass) different plots sizes were simulated by summing up the adjacent BUs in the crop rows and the two forms of harvesting groups. For each plot size simulated and their respective harvests, a variation coefficient (%) was estimated at the crop row. A response surface design was applied, with a dependent variable in the variation coefficient and, with the independent variable, the plot size and number of harvests. Best combination between plot size and number of harvests is seven plants and half the productive cycle in both growing seasons.

Hiệu quả của việc chuyển đổi nuôi tôm sú (Penaeus monodon) sang thẻ chân trắng (Litopenaeus vannamei) ở tỉnh Sóc Trăng

The study was conducted to evaluate the converting of intensive shrimp farming from black tiger shrimp (BS) to white leg shrimp (WS) systems in Soc Trang province through interviews 30 BS farmers and 30 WS farmers from June to December 2015. The collected information includes (1) the technical and financial aspects and (2) the factors affected to farmers’ decisions. The results showed farming seasons, stocking density, survival rate, productivity and harvest size in BS farms (1-2 seasons, 27.13 shrimp/m2, 66.37%, 2.5 tons/ha/season, 63.77 shrimp/kg) were lower than that of WS farms (2-3 seasons, 55.43 shrimp/m2, 67.13%, 4.05 ton/ha/season, 95.37 shrimp/kg). Total cost of WS farms (347.8 VND million/ha/crop) was higher than that of BS (299.2 VND million/ha/crop). Profit in WS farms (135.7 VND million/ha/crop) was also higher than that in BS farms (96.5 VND million/ha/crop). There were four reasons leading to the converting decision in the shrimp farming system. They include diseases, culture duration, benefit per cost and environment. Fifty five percent of shrimp farmers had a desire to keep WS farming system in the future; 23.3% of them tended to BS farming in the upcoming crop; 15% favored both systems and 6.7% switched to other species. Shrimp yield was in a linear relationship with stocking density, survival rate, culture period, harvest size and FCR.

Effects of Management Practices and Environmental Factors on Largemouth Bass Abundance in Illinois Inland Lakes

An understanding of the relative importance of natural factors and management practices affecting largemouth bass (Micropterus salmoides) abundance is key for enhanced angling. Standardized fish surveys, management practices, and environmental data were available from 42 man-made, inland lakes between 1960 and 1991. Management practices tested were largemouth bass stocking, lake rehabilitation, water level manipulation, aquatic vegetation controls, small fish removal, and changes in length limits of harvestable fish. Environmental factors not controlled by management were spring water influx, growing and cooling degree days, and snow depth. Lake rehabilitation (complete drainage and reflooding), changes in length limits, and aquatic vegetation controls were the only significant factors affecting largemouth bass abundance. The largest effects were due to lake rehabilitation, which increased next-year young largemouth bass numbers by 566% on average, and more restrictive limits on harvestable size, with an increase of up to 440% in adult numbers.

Vibratory electromagnetic induction energy harvester on wheel surface of mobile sources

The tire pressure monitoring system (TPMS) research is mostly concentrated in the ultralow-power circuit field. However, one of the biggest challenges is overcoming the unavoidable replacement of batteries owing to their self-discharging, unstable performance by using the energy-harvesting technology. A TPMS must be installed on the wheel surface for permanent operation. Likewise, the energy harvester should be directly installed inside the TPMS circuit to eliminate any additional maintenance. Thus, the size of the energy harvester for independent rotational systems, such as a tire wheel, should be constrained to the battery level. Electromagnetic induction was selected to maximize the power generated by the energy harvester. The optimized model was rationally examined, and the results were compared with the calculated results. In preliminary modeling of the mechanical energy transduction into electrical energy and the parameters in the m-c-k system, the module was predicted to generate about 136 μW of consumable power. A test module was fabricated for practical application. With the experimental constraints, the maximum power consumption was 195 μW under the conditions of a base excitation of 12 Hz and acceleration of 0.5 g for a system volume of about 2.5 cm3.

Study on Drive System of Hybrid Tree Harvester.

Hybrid tree harvester with a 60 kW diesel engine combined with a battery pile could be a “green” forest harvesting and transportation system. With the new design, the diesel engine maintains a constant engine speed, keeping fuel consumption low while charging the batteries that drive the forwarder. As an additional energy saving method, the electric motors work as generators to charge the battery pile when the vehicle moves downhill. The vehicle is equipped with six large wheels providing high clearance over uneven terrain while reducing ground pressure. Each wheel is driven via a hub gear by its own alternating current motor, and each of the three wheel pairs can be steered independently. The combination of the diesel engine and six electric motors provides plenty of power for heavy lifting and pulling. The main component parameters of the drive system are calculated and optimized with a set of dynamics and simulated with AVL Cruise software. The results provide practical insights for the fuel tree harvester and are helpful to reduce the structure and size of the tree harvester. Advantage Environment provides information about existing and future products designed to reduce environmental impacts.

Clearcutting and Site Preparation, but Not Planting, Promoted Early Tree Regeneration in Boreal Alaska

The stand initiation stage decisively influences future forest structure and composition, particularly in the boreal forest which is a stand replacement disturbance driven system. In boreal Alaska, the conventional forest management paradigm has focused on the production of large-dimension timber, particularly white spruce (Picea glauca). However, energy generation and heating from wood is increasing, and is likely to significantly expand total forest harvest, further shifting management focus to fuelwood production. We evaluated the effects of forest harvest management practices on post-harvest regeneration by examining whether harvest type, site preparation method, and reforestation technique resulted in differences in forest regeneration in terms of species presence, dominance, basal area, and total stem biomass using a stochastic gradient boosting (TreeNet algorithm). We recorded diameter at breast height and height of white spruce, birch (Betula neoalaskana), and aspen (Populus tremuloides) in 726 plots from 30 harvest units, distributed across the various harvest and treatment types, harvest years, harvest sizes, and geographical locations. Our results indicate that management practices suitable/acceptable for woody biomass production differ from the more traditional dimensional timber production from white spruce-focused management. Artificial reforestation does not differ from natural regeneration in obtaining more stems or producing greater biomass. Clearcutting and site preparation increased tree regeneration, basal area, and woody biomass when compared to a partial harvest with no site preparation. Planting of white spruce in the Alaskan boreal forest may only be necessary in some specific circumstances, such as years with no/low white spruce seed crop, or in landscapes depleted of seed trees.

TOTAL HEMOCYTES, GLUCOSE HEMOLYMPH, AND PRODUCTION PERFORMANCE OF SPINY LOBSTER Panulirus homarus CULTURED IN THE INDIVIDUAL COMPARTMENTS SYSTEM

Cannibalism can cause high mortality in a lobster culture. To prevent cannibalism, an artificial shel-ter is needed like the individual compartments system (ICS) to ensure that there is no contact bet-ween lobsters. This study aimed to evaluate the application of ICS on total hemocytes glucose hemo-lymph, production performance, and determine the shape of more effective ICS to minimize stress level of lobster. The treatments used for various application shape of ICS was tubular ICS, triangle ICS, square ICS, and shelter PVC pipes as control. Lobster maintenance was conducted in outdoor for 60 days. The results indicated that physiological responses with square ICS treatment were more effective to reduce stress level compared with other treatments (p<0.05). Application of ICS was more optimal to improved SR (p<0.05) and growth of lobster (p>0.05). Overall, treatment of square ICS was opti-mal related to production performance i.e. SR 88.89±5.24%, SGR 0.61±0.49%/day, with harvest size of total length 137.31±8.11 mm/ind, weight 58.83±4.78 g/ind, and FCR 22.71±1.72. Application of ICS in lobster culture was effective to reduce stress level as indicated from total hemocytes and gluco-se hemolymph, and support optimal production performance. Lobster culture using a square ICS sha-pe was effective to minimize stress level, compared with tubular ICS and triangle ICS.Keywords: cannibalism, glucose, hemocytes, individual compartments system, lobster, production

TOTAL HEMOCYTES, GLUCOSE HEMOLYMPH, AND PRODUCTION PERFORMANCE OF SPINY LOBSTER Panulirus homarus CULTURED IN THE INDIVIDUAL COMPARTMENTS SYSTEM

<p><em>Cannibalism can cause high mortality in a lobster culture. To prevent cannibalism, an artificial shel-ter is needed like the individual compartments system (ICS) to</em><em> ensure that there is no contact bet-ween lobsters.</em><em> This study aimed to evaluate the application of ICS on total hemocytes glucose hemo-lymph, production performance, and determine the shape of more effective ICS to minimize stress level of lobster. The treatments used for various application shape of ICS was tubular ICS, triangle ICS, square ICS, and shelter PVC pipes as control. Lobster maintenance was conducted in outdoor for 60 days. The results indicated that physiological responses with square ICS treatment were more effective to reduce stress level compared with other treatments (p<0.05). Application of ICS was more optimal to improved SR (p<0.05) and growth of lobster (p>0.05). Overall, treatment of square ICS was opti-mal related to production performance i.e. SR 88.89±5.24%, SGR 0.61±0.49%/day, with harvest size of total length 137.31±8.11 mm/ind, weight 58.83±4.78 g/ind, and FCR 22.71±1.72. Application of ICS in lobster culture was effective to reduce stress level as indicated from total hemocytes and gluco-se hemolymph, and support optimal production performance. Lobster culture using a square ICS sha-pe was effective to minimize stress level, compared with tubular ICS and triangle ICS.</em></p><p><strong><em></em></strong><strong><em>Keywords:</em></strong><em> cannibalism, glucose, hemocytes, individual compartments system, lobster, production</em></p>

Folded Spring and Mechanically Switching SSHI for High Performance Miniature Piezoelectric Vibration Energy Harvester

To downsize the clamp area and increase the output power of the harvester, we developed a miniature piezoelectric vibration energy harvester with combining a Z-shaped folded spring and a mechanically-switching SSHI (synchronized switch harvesting on inductor). The overall harvester size is 4×2×3 cm3. The FEM analysis revealed that the output power increases and the value of the 1st and 2nd resonance frequencies move closer as the angle of the Z-shaped spring decreases, therefore, the smaller angle would be more promising. The experimental results showed that the maximum output power of our harvester for the 1st (20.2 Hz) and 2nd (53.0 Hz) resonance frequencies at the applied acceleration of 4.9 m/s2 are 088 and 0.98 mW, respectively. The reason for a marked enhancement of the output power for the 2nd resonance frequency is attributed to the vertical movement of the 2nd vibrational mode which applies larger mechanical stress to the piezo ceramic and achieves better electrical contact between the tip of the Z-shaped spring and the spring plunger.

Incorporation of tail weight and tail percentage at harvest size in selection programs for the Pacific white shrimp Penaeus (Litopenaeus) vannamei

The objective of this study was to estimate the value of incorporating tail weight (TW), and tail percentage (TP) as additional selection criteria to body weight (BW) at harvest size in Pacific white shrimp (Penaeus (Litopenaeus) vannamei) breeding programs. A total of 8208 records of BW and TW at harvest size were obtained in 2010 from four performance ponds located on the northwest coast of Mexico, where shrimp were grown under a range of commercial-like management conditions. This study used information from 150 female families (112 sires). The population structure is based on full- and half-sib families. (Co)variance component estimates for BW, TW, and TP were estimated using REML and ASReml software with bivariate animal models. A profit equation was developed to determine the relative economic value for BW and TP in shrimp in Mexico. Selection index procedure was used to assess the effect of including or not including TP as an additional selection criterion to BW in terms of selection response for an economic breeding objective. Heritabilities (±standard error) for BW, TW and TP were estimated as 0.15±0.08, 0.16±0.08 and 0.12±0.04, respectively. Genetic and phenotypic correlations between body weight and tail weight were essentially 1 (0.99±0.01 and 0.99±0.001, respectively), which implies that, in practical terms, they are statistically almost the same trait. Genetic correlation between TW and TP was slightly higher (0.48±0.24) than that between BW and TP (0.36±0.28), but both have relatively high standard errors. Economic selection responses using only BW compared to an economic selection index incorporating BW and TP as selection criteria were 99.5 and 96.6% with evaluation based on one phenotypic record and the average of 54 full-sib records, respectively. Increasing the relative economic weight for TP tenfold changed these figures to 99.4 and 96.3%, respectively. In conclusion, results from this study indicate that there is no reason to replace BW with TW, or to incorporate TP as an additional selection criterion for breeding programs in P. vannamei. Statement of relevanceAlthough tail weight is the main marketing product in the shrimp industry, it has a very high phenotypic and genetic correlation with body weight. Measuring tail traits adds costs and do not improve the efficiency of P. vannamei breeding programs.

Variability of Mya arenaria growth along an environmental gradient in the Plum Island Sound estuary, Massachusetts, USA

An understanding of the environmental factors that determine how clam growth varies in space and time improves effective mariculture and shellfish management. We examined the importance of temperature, salinity and chlorophyll-a in controlling the spatial pattern of Mya arenaria growth, the commercially important soft-shell clam, in the Plum Island Sound estuary in northeastern Massachusetts, USA. We collected clams (>5.08 cm) monthly during the April to November growing season from which we determined growth rate, maximum size (L-infinity), and time to reach a harvestable size. We also surveyed selected sites along the estuary to estimate the relationship between clam size and weight. We collected environmental data along the estuary, and our data were complemented with data collected and maintained by the Plum Island ecosystems long-term ecological research project. Clams reached harvestable size fastest and had the greatest L-infinity at the most oceanic site (Yacht Club) in the estuary. Clams had the smallest L-infinity and were slowest to reach the harvestable size at the least oceanic site (Railroad Meander). The spatial patterns of clam growth were best explained by a positive distribution of salinity. Salinity significantly accounted for 95 % of the spatial variation of clam growth in the estuary. Snow melt in spring increases freshwater input to the estuary and results in the lowest spring salinity during a year, and this explained the upper estuary limit of clam distribution. IPCC-projected climate change will cause sea-level rise and increasing precipitation in the northeastern USA, which will modify the spatial pattern of salinity in the region’s estuaries. Our research therefore suggests that future management of M. arenaria, an important economic resource for the local economy, should be concerned with the changes of salinity distribution under climate and land-use change.

Diet, size and location as determinants of n-3 long-chain polyunsaturated fatty acid content in farmed Atlantic Salmon (Salmo salar )

We explored how currently manufactured feeds, under real-world conditions and across geographically distinct locations, promoted flesh n-3 long-chain polyunsaturated fatty acid (LC-PUFA, i.e. 20:5n-3 + 22:6n-3) levels in various life stages of farmed Atlantic Salmon (Salmo salar). Potential effects on flesh LC-PUFA included: (1) diet and fish weight at one Canadian east coast farm, (2) diet and farm location across six east coast farms, and (3) diet and farm location between east and west coast farms. For objectives 1 and 2, salmon were fed a currently manufactured feed (labelled as feeds A, B or C) and harvested at 1, 3 and 5 kg. LC-PUFA levels in 5 kg (harvest size) fish were then compared to previously published values for west coast farmed Atlantic Salmon (Obj. 3). Combined results revealed that variability in LC-PUFA levels was better explained by diet than by fish weight or farm location. Fish size, however, was also important for two reasons. First, feeding a high LC-PUFA diet early in life appeared important for ensuring high LC-PUFA levels at harvest size. Second, salmon flesh LC-PUFA levels increased with fish size, but only when dietary LC-PUFA was provided above an apparent threshold value (~3000 mg per 100 g or 10% of total fatty acids) that likely promoted LC-PUFA incorporation and storage. Overall, our comparison makes new recommendations for feed manufacturers and demonstrates that farmed Atlantic Salmon reared under real-world conditions on currently available salmon feeds were good sources of n-3 LC-PUFA to consumers.

Do logging concessions decrease the availability to villagers of foods from timber trees? A quantitative analysis for Moabi (Baillonella toxisperma), Sapelli (Entandrophragma cylindricum) and Tali (Erythrophleum suaveolens) in Cameroon

Many species of timber trees in Cameroon are exploited by logging companies for timber and by forest-dependent communities for non-timber forest products (NTFPs). Quantitative analyses were conducted within and near forest concessions in Cameroon to determine the density of multiple use tree species that provide both timber for industry and foods consumed by local populations (fruit and oil or edible caterpillars), and how this has been affected by logging. Individuals of the three species (Moabi, Baillonella toxisperma; Sapelli, Entandrophragma cylindricum; and Tali, Erythrophleum suaveolens), including their stumps, were identified and measured on 5ha (100m×500m) sample plots around 4 villages and in 2 concessions. Around each village 21 sample plots, stratified by distance, were laid out along three transects extending 10km towards the concession, each oriented 45° from the other. In concessions, 20 plots were established within the 2012 cutting unit after timber harvesting, using a stratified random system. Moabi trees occurred at the lowest densities: around villages, 22.8±3.3/100ha of precommercial individuals and 5.0±1.4/100ha of individuals of harvestable size (⩾80cmdbh); on concessions, 7.5±2.4 precommercial trees/100ha, and 0–2.0±1.4/100ha harvestable individuals. Densities of Sapelli trees were not significantly different between villages and concessions, averaging 32.6±3.8/100ha and 37.5±5.5/100ha, respectively, for precommercial sizes and 9.5±2.2/100ha and 6±1.6/100ha, respectively, for harvestable trees (⩾100cmdbh). Pre-commercial Tali trees occurred at lower densities (3.8±0.9/100ha) around villages, as compared to 11.5±3.1/100ha on concessions. Harvestable Tali trees (⩾60cmdbh) occurred at the same densities around villages and on concessions (56.0±7.2/100ha). Half, or more, of commercial-sized trees of caterpillar-hosting species were left standing after harvest on concessions (89–94% of Tali; 50–79% of Sapelli), reflecting constraints due to timber quality, market demand and inaccessibility. No harvestable Moabi trees were logged from the 2012 cutting areas, reflecting agreements between communities and concessionaires to leave them for fruit and oil, but densities were so low it will be important that villagers conserve those around their villages. Stumps of all three species were found around villages, revealing that mechanisms for negotiation are also needed among villagers with interests in either timber or non-timber resources obtained from the same tree species.

Recovery rates for eight commercial sea cucumber species from the Fiji Islands

Determination of the original weight and length of sea cucumbers processed and dried to become bêche-de-mer (BDM), is an important tool in sea cucumber fishery management. The only management mechanism for the sea cucumber fishery in the Fiji Islands is a minimum length prescribed for BDM for export. However, different commercial species have different shrinkage rates during processing and previous studies have suggested modification of fisheries management for sea cucumbers to include species-specific minimum harvest size limits This study determined weight-based and length-based recovery rates (i.e. the length/weight of BDM recovered after processing from the initial length/weight of fresh sea cucumber), for eight commercial sea cucumber species following processing to BDM; White Teatfish (Holothuria fuscogilva), Black Teatfish (Holothuria whitmaei), Tigerfish (Bohadschia argus), Surf Redfish (Actinopyga mauritiana), Hairy Blackfish (Actinopyga miliaris), Stonefish (Actinopyga lecanora), Prickly Redfish (Thelenota ananas) and Sandfish (Holothuria scabra). Length and weight recovery rates varied between species and ranged from the highest recovery values of 54.9% for length and 11% for weight in Black Teatfish, to the lowest recovery values of 32.6% for length and 3.0% for weight in Sandfish and Tigerfish, respectively. Length-based and weight-based relationships were generated for each species through the various stages of processing from fresh to dried (BDM) allowing estimation of initial fresh weight/length from partially or fully processed BDM and vice versa. Information generated in this study provides a basis for developing more species-specific harvest size restrictions for sea cucumbers in the Fiji Islands, and has application in stock assessment studies, estimation of harvest data, monitoring of harvest size limits and standardizing catch data.

Cannibalism and Performance Evaluation of Hybrids betweenClarias batrachusandClarias gariepinus

AbstractCannibalism is an important characteristic of African catfish that significantly reduces the number of stocked fish at harvest. This study evaluates the effect of reciprocal hybridization ofClarias batrachusandClarias gariepinuson cannibalism and growth performance of their progenies in an indoor rearing system. The result obtained reveals excellent performance of hybrids ofC. gariepinus♂ andC. batrachus♀ over the purebreds in terms of growth. However, the reciprocal hybrids betweenC. gariepinus♀ andC. batrachus♂ all died few hours after hatching. Cannibalism was significantly reduced in the crosses betweenC. gariepinus♂ andC. batrachus♀ with 100% survival after five months of culture. Hence, this could be exploited in commercial production of catfish to reduce cannibalism and increase harvest size of fish farmers.

Cross‐seasonal effects on waterfowl productivity: Implications under climate change

ABSTRACTPrevious efforts to relate winter‐ground precipitation to subsequent reproductive success as measured by the ratio of juveniles to adults in the autumn failed to account for increased vulnerability of juvenile ducks to hunting and uncertainty in the estimated age ratio. Neglecting increased juvenile vulnerability will positively bias the mean productivity estimate, and neglecting increased vulnerability and estimation uncertainty will positively bias the year‐to‐year variance in productivity because raw age ratios are the product of sampling variation, the year‐specific vulnerability, and year‐specific reproductive success. Therefore, we estimated the effects of cumulative winter precipitation in the California Central Valley and the Mississippi Alluvial Valley on pintail (Anas acuta) and mallard (Anas platyrhnchos) reproduction, respectively, using hierarchical Bayesian methods to correct for sampling bias in productivity estimates and observation error in covariates. We applied the model to a hunter‐collected parts survey implemented by the United States Fish and Wildlife Service and band recoveries reported to the United States Geological Survey Bird Banding Laboratory using data from 1961 to 2013. We compared our results to previous estimates that used simple linear regression on uncorrected age ratios from a smaller subset of years in pintail (1961–1985). Like previous analyses, we found large and consistent effects of population size and wetland conditions in prairie Canada on mallard productivity, and large effects of population size and mean latitude of the observed breeding population on pintail productivity. Unlike previous analyses, we report a large amount of uncertainty in the estimated effects of wintering‐ground precipitation on pintail and mallard productivity, with considerable uncertainty in the sign of the estimated main effect, although the posterior medians of precipitation effects were consistent with past studies. We found more consistent estimates in the sign of an interaction effect between population size and precipitation, suggesting that wintering‐ground precipitation has a larger effect in years of high population size, especially for pintail. When we used the estimated effects in a population model to derive a sustainable harvest and population size projection (i.e., a yield curve), there was considerable uncertainty in the effect of increased or decreased wintering‐ground precipitation on sustainable harvest potential and population size. These results suggest that the mechanism of cross‐seasonal effects between winter habitat and reproduction in ducks occurs through a reduction in the strength of density dependence in years of above‐average wintering‐ground precipitation. We suggest additional investigation of the underlying mechanisms and that habitat managers and decision‐makers consider the level of uncertainty in these estimates when attempting to integrate habitat management and harvest management decisions. Collection of annual data on the status of wintering‐ground habitat in a rigorous sampling framework would likely be the most direct way to improve understanding of mechanisms and inform management. © 2016 The Wildlife Society.

Management compromises and the sustainability of palm populations in Mayan homegardens

The sustainability of a homegarden can be evaluated not only as its species richness and eco-systemic role, but also as the result of management practices affecting resource sustainability. Sabal spp. have been managed since Colonial times into homegardens, at present, its mature leaves are mostly used in roof building of traditional Mayan homes. Along a three-year study, we evaluated management sustainability of Sabal yapa and S. mexicana populations in two homegardens of Maxcanú, Yucatan, Mexico by the use of prospective and retrospective demographic analyses. We calculated sustainability based on population growth rate ( ? ). We used the prospective elasticity model to estimate the more sensible vital rates of the palm populations, and the retrospective analysis to calculate the effect of management practices on the annual variation of the palms population ? values. Care of young plants and occasional seed planting were among the management practices that increased the density of palms having an adequate harvesting size. The stages of the palms´ life cycle that are critical for sustainable population management are the adult and juvenile stages. An event of felling of adult palms had a negative effect in the population´s sustainability. Other practices in the homegarden such as weeding and watering of fruit trees increased the probabilities of survival. Our study showed that the management of natural resources in homegardens involves compromises, and is not always focused on the sustainability of specific resources, but rather on the integrated management of the agroforestry system.

Number of Intratumoral T Lymphocytes Is Associated With Lymph Node Size, Lymph Node Harvest, and Outcome in Node-Negative Colon Cancer

We postulated that lymph node (LN) harvest and LN size are influenced by immunologic effects. To investigate this hypothesis, we performed a retrospective analysis of 170 node-negative colon cancer cases to evaluate the density of intratumoral T lymphocytes (ITLs). CD3- and CD8-positive T cells were counted using a digital system. The ITL density was significantly increased in cases with sufficient LN harvest and high numbers of LNs larger than 5 mm (LN5). High ITL numbers were associated with improved cancer-specific survival. The analysis of the immune score revealed a significantly different cancer-specific outcome (P = .024), with no cancer-related death in the group with the highest score. The immune score and tumor budding were independently prognostic. ITL density is independently prognostic and associated with LN harvest and LN size. The immune response is very likely the true explanation for the known prognostic effect of the LN harvest in colon cancer.

Timber harvest and tree size near nests explains variation in nest site occupancy but not productivity in northern goshawks (Accipiter gentilis)

Conservation concern for the northern goshawk (Accipiter gentilis) reflects evidence that goshawks may abandon nest sites or suffer from reduced nesting success in response to some forms of timber harvest. However, this evidence is mixed and has yet to be reviewed systemically and quantitatively. Therefore, we conducted a meta-analysis to assess the extent to which timber harvest and tree size explain variation in goshawk productivity and site occupancy. Goshawk productivity was not significantly explained by the presence of nearby timber harvest nor by the average size of nearby trees either in North America or in Eurasia or when averaged across all studies. Effect sizes differed dramatically among studies and the average effect size was close to zero (Zr=0.04). However, timber harvest and tree size together more strongly explained goshawk occupancy of nest sites or territories. Within studies, goshawk nest sites or territories with less timber harvest nearby or relatively larger trees were, in most cases, more likely to be occupied. When we estimated average effect sizes separately for the two continents, the averages were moderate, consistent (Zr=0.23–0.27), and significantly>0. When we combined studies from North America and Eurasia, average effect sizes for timber harvest (Zr=0.24) and tree size (Zr=0.25) were similar in strength and both significantly>0. Thus taken together, our results suggest that although both timber harvest and a lack of large trees are associated with lower occupancy by nesting goshawks, pairs that nest near timber harvest or in small trees have indistinguishable nesting success from pairs nesting in large trees or farther from timber harvest. We found substantial heterogeneity in results among studies, especially within North America, which is not surprising given that studies differed greatly in research methods, forest type, and forest management. In conclusion, our results suggest goshawk nest sites in populations of conservation concern, such as A. g. laingi, may need more protection from timber harvest than they are currently receiving. Equally important, to better understand effects of forest management on goshawks, we recommend additional studies designed to: (1) better identify the spatial and temporal extent of the effect of timber harvest on goshawk site occupancy; and (2) determine what goshawks do and where they go after a timber harvest.