The document describes research on the distribution of the invasive cactus moth (Cactoblastis cactorum) and its host plant (Opuntia stricta) in Florida. Researchers surveyed over 1,300 plots using stratified random and adaptive cluster sampling. They found the invasive moth primarily on O. stricta and O. humifusa var. ammophila. Generalized linear mixed models showed O. stricta occurrence was positively related to detritus density and vegetation density. Models also showed invasive moth occurrence on O. stricta was positively related to host plant height and percent cover. The research provides insights into factors that structure the occurrence of the invasive moth and its cactus host in Florida.
The document summarizes an experiment conducted by Jennifer Griffith, Taylor Wadley, and Daniel Crall to study the effects of light intensity and pH on the regeneration of African violets (Saintpaulia ionantha) through tissue culture. They tested five different pH levels of growth media (4.0-8.0) and three lights varying in color temperature (4100K, 6500K, 4100K) and color rendering index (89, 84, 70). They hypothesized the greatest shoot production would occur with a pH of 6.0 and light with a 4100K color temperature and 89 CRI, as these conditions are closest to established protocols and light spectra promoting growth.
14. weed management methods and integrated weed management By Allah dad Khan Mr.Allah Dad Khan
The document discusses weed management methods and integrated weed management. It provides details on various methods of weed control including prevention, eradication, control and management. It describes cultural, mechanical, chemical and biological weed control techniques. Integrated weed management is defined as using a combination of two or more weed control methods at low input levels to reduce weeds below an economic threshold level while minimizing environmental impacts. The approach aims to shift crop-weed competition in favor of crops.
This document discusses spring dead spot, a disease that affects hybrid bermudagrasses. It is caused by the pathogen Ophiosphaerella herpotricha which infects root tissue in the fall and limits the plant's ability to overwinter. Infected plants remain dormant in the spring and eventually die. The document examines potential management strategies for spring dead spot including fungicide applications, nitrogen sources, sulfur, and fraze mowing. Research presented found that sulfur applications and two years of fungicide treatments may provide control. Fraze mowing alone is not a cure but may speed recovery when integrated with other practices. The predominant pathogen in Missouri is O. herpotricha and lowering soil pH through ammonium
What is an optimal spray threshold which results in optimal yield protection?Jennifer Blackburn
1) Researchers conducted field experiments across 5 states and 6 locations to determine optimal spray thresholds for protecting sorghum yield from aphid damage.
2) Results showed that economic thresholds varied by location but generally ranged from 30-135 aphids per leaf. Lower thresholds were recommended for more susceptible hybrids or under hot/dry conditions favoring aphid increase.
3) Next steps include investigating surrogate measures for estimating aphid loads, effects of plant stage and health, hybrid sensitivity, and natural enemies to refine economic thresholds.
This document summarizes a study examining latitudinal variation in herbivory and higher trophic interactions involving native and invasive genotypes of common reed (Phragmites australis). The study found that gall infestation by introduced fly species (Lipara spp.) increased with latitude and was higher on native and invasive P. australis genotypes in North America compared to Europe, suggesting enemy release contributes to invasion success. Higher trophic levels like parasitoids and predators that influence Lipara spp. in Europe were largely absent in North America. Overall, the results show latitudinal gradients in species interactions and support the idea that a lack of natural enemies facilitates P. australis invasion.
This document summarizes a scientific paper that studied methods of vegetation analysis in a grassland ecosystem using plot and transect sampling techniques. The study found that as the sampled area increases, the number of plant species also increases, following a species-area curve. One species, Species A, was found to dominate the area based on higher values for density, dominance, and frequency compared to other species. The diversity of species in the area was calculated to be moderately diverse using Simpson's and Shannon-Wiener indices. The study demonstrated how plot and transect sampling can be used to analyze factors like species richness, cover estimation, zonation, and density in a grassland ecosystem.
Genetic Variability for yield in Maize (Zea mays l.) inbred linesFekaduKorsa
This document summarizes an MSc thesis that studied genetic variability in maize inbred lines in central Ethiopia. 25 maize inbred lines were evaluated in a 5x5 triple lattice design trial. A number of agronomic traits were measured including days to tasseling/silking, plant/ear height, leaf characteristics, tassel/ear traits, yield components and grain yield. Analysis of variance showed significant genetic variability for most traits. Estimates of variance components, phenotypic and genotypic coefficients of variation, heritability and genetic advance were also calculated to understand the genetic potential of the lines for selection and breeding. The study provides useful information on the nature and extent of genetic diversity present in the maize in
The document summarizes an experiment conducted by Jennifer Griffith, Taylor Wadley, and Daniel Crall to study the effects of light intensity and pH on the regeneration of African violets (Saintpaulia ionantha) through tissue culture. They tested five different pH levels of growth media (4.0-8.0) and three lights varying in color temperature (4100K, 6500K, 4100K) and color rendering index (89, 84, 70). They hypothesized the greatest shoot production would occur with a pH of 6.0 and light with a 4100K color temperature and 89 CRI, as these conditions are closest to established protocols and light spectra promoting growth.
14. weed management methods and integrated weed management By Allah dad Khan Mr.Allah Dad Khan
The document discusses weed management methods and integrated weed management. It provides details on various methods of weed control including prevention, eradication, control and management. It describes cultural, mechanical, chemical and biological weed control techniques. Integrated weed management is defined as using a combination of two or more weed control methods at low input levels to reduce weeds below an economic threshold level while minimizing environmental impacts. The approach aims to shift crop-weed competition in favor of crops.
This document discusses spring dead spot, a disease that affects hybrid bermudagrasses. It is caused by the pathogen Ophiosphaerella herpotricha which infects root tissue in the fall and limits the plant's ability to overwinter. Infected plants remain dormant in the spring and eventually die. The document examines potential management strategies for spring dead spot including fungicide applications, nitrogen sources, sulfur, and fraze mowing. Research presented found that sulfur applications and two years of fungicide treatments may provide control. Fraze mowing alone is not a cure but may speed recovery when integrated with other practices. The predominant pathogen in Missouri is O. herpotricha and lowering soil pH through ammonium
What is an optimal spray threshold which results in optimal yield protection?Jennifer Blackburn
1) Researchers conducted field experiments across 5 states and 6 locations to determine optimal spray thresholds for protecting sorghum yield from aphid damage.
2) Results showed that economic thresholds varied by location but generally ranged from 30-135 aphids per leaf. Lower thresholds were recommended for more susceptible hybrids or under hot/dry conditions favoring aphid increase.
3) Next steps include investigating surrogate measures for estimating aphid loads, effects of plant stage and health, hybrid sensitivity, and natural enemies to refine economic thresholds.
This document summarizes a study examining latitudinal variation in herbivory and higher trophic interactions involving native and invasive genotypes of common reed (Phragmites australis). The study found that gall infestation by introduced fly species (Lipara spp.) increased with latitude and was higher on native and invasive P. australis genotypes in North America compared to Europe, suggesting enemy release contributes to invasion success. Higher trophic levels like parasitoids and predators that influence Lipara spp. in Europe were largely absent in North America. Overall, the results show latitudinal gradients in species interactions and support the idea that a lack of natural enemies facilitates P. australis invasion.
This document summarizes a scientific paper that studied methods of vegetation analysis in a grassland ecosystem using plot and transect sampling techniques. The study found that as the sampled area increases, the number of plant species also increases, following a species-area curve. One species, Species A, was found to dominate the area based on higher values for density, dominance, and frequency compared to other species. The diversity of species in the area was calculated to be moderately diverse using Simpson's and Shannon-Wiener indices. The study demonstrated how plot and transect sampling can be used to analyze factors like species richness, cover estimation, zonation, and density in a grassland ecosystem.
Genetic Variability for yield in Maize (Zea mays l.) inbred linesFekaduKorsa
This document summarizes an MSc thesis that studied genetic variability in maize inbred lines in central Ethiopia. 25 maize inbred lines were evaluated in a 5x5 triple lattice design trial. A number of agronomic traits were measured including days to tasseling/silking, plant/ear height, leaf characteristics, tassel/ear traits, yield components and grain yield. Analysis of variance showed significant genetic variability for most traits. Estimates of variance components, phenotypic and genotypic coefficients of variation, heritability and genetic advance were also calculated to understand the genetic potential of the lines for selection and breeding. The study provides useful information on the nature and extent of genetic diversity present in the maize in
Cobb, Seltmann, Franz. 2014. The Current State of Arthropod Biodiversity Data...taxonbytes
Cobb et al. 2014. The Current State of Arthropod Biodiversity Data: Addressing Impacts of Global Change. Presented at https://www.idigbio.org/content/collections-21st-century-symposium Program available at https://www.idigbio.org/wiki/index.php/Collections_for_the_21st_Century
Opportunities to Practically Scale-up Perennial FeedstocksAmanda Bilek
Presented by Vance Owens, Director of North Central Sun Grant Center, South Dakota State University on December 8, 2014 at Minnesota Bioenergy Feedstock Development meeting and forum.
Macroinvertebrate Communities in Ephemeral Ponds: Effects of Competition, Lan...DistribEcology
- The study examined how competitive interactions with salamander larvae and abiotic habitat variables determine macroinvertebrate species richness in ephemeral ponds.
- Experimental sites varied in canopy cover (open or closed) and presence/absence of salamander larvae. Species richness was highest in open sites and was best predicted by abiotic habitat variables like hydroperiod rather than biotic interactions.
- Competition from salamander larvae appeared to have little impact on species richness, possibly due to the highly disturbed nature of ephemeral ponds and low larval densities.
ATBI Mapping Program: Species Distribution Models for Great Smoky Mountains N...Tanner Jessel
ATBI Mapping Program: Where Do All These Species Live? – Tanner Jessel The ATBI not only focuses on scientific research and education, but also on conservation stewardship of the national park. One of the most valuable conservation questions it is answering is: Where do the thousands of species that call the Smokies "home" actually live? To date the ATBI not only has dot maps for almost all the species, but for those with enough (>30) point locations our partners at the University of Tennessee can produce "predictive models" of where they occur over the entire 800+ square mile park... an Atlas of Species!
Line × tester analysis for yield contributing morphological traits in Triticu...Innspub Net
The present study was carried out for the development of the water stress wheat cultivars with higher grain yield by studying the genetic basis of crucial morphological traits. Nine wheat genotypes were grouped into six lines and three testers and these parents were crossed line x tester fashion. Eighteen crosses including nine parents were planted in the field in randomized complete block design with three replications. Three drought tolerant varieties Chakwal-50, Chakwal-86 and Kohistan-97 were also sown to compare the results in water stress environment. Highest negative GCA effects were observed in WN-36 for plant height (-6.17) and flag leaf area (-1.53), while for peduncle length it was noted in 8126 lines (-1.15). Highest positive GCA effects were observed in WN-32 for a number of grains per spike (5.21), grain yield per plant (2.08) and for spikelet per spike (0.33), while for 8126 and WN-10 the number of tillers per plant (0.67) and spike length (0.25) was found, respectively. The crosses 9451 × WN-25, WN-36 × 8126, WN-10 × 8126 showed highest negative SCA effects for plant height (-8.06), flag leaf area (-2.89), and peduncle length (-2.05), respectively. Moreover, the cross combinations of WN-36 × WN-25, WN-32 × WN-25 and AARI-7 × 9526 showed positive SCA effects for number of tillers per plant (1.52), spike length (0.72) and number of spikelet per spike (0.84) respectively, while the interaction of WN-35 × 8126 crosses showed highest positive SCA effects for number of grains/spike (5.69) and grain yield/plant (2.75). The parental material used in this study and cross combinations obtained from these parents may be exploited in future breeding endeavors.
This document is the first progress report of Amelia Lamb's research on the effects of shrubs and understory annual plants on kangaroo rat species in a desert annual community. The report summarizes previous literature on positive plant interactions and the stress gradient hypothesis. It also describes the study site and species, and outlines the methods for surveys to examine animal activity along a shrub and annual plant gradient, and foraging experiments using giving-up density trials to study kangaroo rat foraging patterns. Current objectives include further analyzing pilot study data, and carrying out extensive field surveys and experiments in April and May.
This document summarizes a study on the mechanisms of resistance to the sorghum shoot fly, Atherigona soccata, in sorghum. The study evaluated different components of resistance (antixenosis, antibiosis, tolerance) in resistant and susceptible sorghum genotypes under field and greenhouse conditions. Key findings include: 1) Resistant genotypes experienced lower deadheart formation, produced more productive tillers, and insects fed on resistant genotypes had longer larval periods and lower survival rates. 2) Physico-chemical traits like leaf glossiness and trichome density were associated with resistance while chlorophyll content and leaf wetness were associated with susceptibility. 3) Deadheart formation, eggs on leaves, leaf gloss
L37 gedrag van planten, kan dat wel theo elzengaTycho Malmberg
Plants exhibit complex behaviors in response to environmental stimuli. They actively forage for resources like light, water, and nutrients through phenotypic plasticity rather than movement. Receptor proteins allow plants to sense myriad signals and integrate the information to determine adaptive responses. Competition between plants mimics behaviors seen in social insects as roots forage and compete for soil resources through self/non-self discrimination and communication between individuals. Parasitic plants like dodder exhibit targeted "hunting" behaviors in attaching to hosts through foraging decisions that maximize energy gain.
Presentation made by Andy Jarvis in the Latin American Congress of Chemistry on 30th September 2010, in the symposium on Biodiversity and Ecosystems: the role of the chemical sciences.
Bari a 2nd iwsrs conference - izmir - 29 april2014ICARDA
This document summarizes a symposium on predicting and locating sources of resistance to stripe rust in durum wheat genetic resources. It discusses using a Focused Identification of Germplasm Strategy (FIGS) approach to screen wheat genebank accessions based on environmental variables associated with traits of interest, like disease resistance. Models are developed to predict potential resistance in accessions based on climate data from collection sites. Results show the support vector machine, random forest, and neural network models accurately classified known resistant and susceptible accessions, with areas under the ROC curve of 0.72 to 0.74.
Community resistance to biological invasions : role of diversity and network ...Alison Specht
The presentation of the CESAB group LOLA-BMS at the 2016 french ecology conference in the FRB-CESAB session "Using a treasury of knowledge to tackle complex ecological questions." Presented by François Massol and Patrice David
This document discusses the use of pollen analysis to study past vegetation and climate changes. Key points include:
- Pollen grains can be used to identify plant species due to their unique morphology and are well-preserved in sediments.
- Pollen production varies among plant species and those dispersed by wind are overrepresented in sediments.
- Changes in pollen percentages over time are interpreted to reflect shifts in vegetation and climate based on plant ecological requirements and modern analogs.
- Other proxies like macrofossils provide direct plant evidence but are less widely available than pollen.
No 8. response of mukhikachu (colocasia esculenta l.) cv. bilashi to plant sp...PARTNER, BADC, World Bank
The document summarizes a study on the effect of different plant spacing on the growth, yield and storability of mukhikachu (Colocasia esculenta L.) cv. Bilashi. Four spacing treatments were tested: S1 (60 cm × 20 cm), S2 (60 cm × 30 cm), S3 (60 cm × 40 cm), and S4 (60 cm × 50 cm). Maximum individual corm weight, number of suckers per hill, yield of corms and cormels per hectare were obtained from S3 (60 cm × 40 cm) spacing. However, plant spacing did not significantly affect the storability of cormels. The study found that a spacing of
This document summarizes research on ranaviruses, which are pathogens that can cause disease outbreaks in amphibians, reptiles, and fish. Ranaviruses have been detected globally and can infect over 70 amphibian species from 14 families on 5 continents. Susceptibility and mortality from ranavirus infection varies between species and life stages. Some species may act as reservoirs or amplification hosts. There is evidence that ranaviruses can transmit between classes of vertebrates (e.g. from fish to amphibians). Stressors like temperature, pollution, and genetic isolation can increase susceptibility. Ranaviruses have been associated with local population declines and extirpations, especially of rare species.
This document describes techniques and procedures used in nematology laboratories in South Africa. It discusses nematode sampling methods, including sampling equipment, size and area, depth, and timing. Proper handling, labeling, transport, and storage of samples is also covered. Visual examination of plant material for nematode symptoms is described, such as root galls caused by root-knot nematodes or cysts from cyst nematodes. The document provides concise technical information on standard nematology laboratory practices.
Evolution of North American MicruracarusRachel Shoop
My research focuses on the evolution of North American water mites in the genus Arrenurus, Subgenus Micruracarus. In this presentation, I discuss why I chose to study these little known critters, and present some preliminary findings. Please contact me for more info.
This document summarizes a study on using cover crops to manage the root-knot nematode (Meloidogyne incognita) in yam production systems. Pot and field experiments tested the effect of 10 cover crops on M. incognita populations and yam tuber damage. Results showed that tagetes, crotalaria, and aeschynomene cover crops significantly reduced nematode densities and yam damage, while lablab, mucuna, and cowpea supported high nematode populations. The document concludes that tagetes, crotalaria, and aeschynomene should be incorporated into yam farming to control root-knot nematodes.
This document discusses various methods used to measure biodiversity, including biological sampling techniques to estimate species density and abundance. Some key methods mentioned are line transects, quadrats, capture-recapture, traps, aerial photographs, and counts of artifacts. It also discusses indices to quantify biodiversity, such as Simpson's Index and Shannon-Wiener Index, and gives examples of their calculation and interpretation. Finally, it covers topics like endemism levels in Australia and measures of extinction risk.
The population-level consequences of native and invasive herbivores for nativ...Kristen Sauby
We explored the joint effects of native and invasive insect herbivory on plant population growth using a set of closely interacting species: two species of native cacti (Opuntia) in Florida and two cactus moth species (the native Melitara prodenialis and the invasive South American Cactoblastis cactorum).
Cobb, Seltmann, Franz. 2014. The Current State of Arthropod Biodiversity Data...taxonbytes
Cobb et al. 2014. The Current State of Arthropod Biodiversity Data: Addressing Impacts of Global Change. Presented at https://www.idigbio.org/content/collections-21st-century-symposium Program available at https://www.idigbio.org/wiki/index.php/Collections_for_the_21st_Century
Opportunities to Practically Scale-up Perennial FeedstocksAmanda Bilek
Presented by Vance Owens, Director of North Central Sun Grant Center, South Dakota State University on December 8, 2014 at Minnesota Bioenergy Feedstock Development meeting and forum.
Macroinvertebrate Communities in Ephemeral Ponds: Effects of Competition, Lan...DistribEcology
- The study examined how competitive interactions with salamander larvae and abiotic habitat variables determine macroinvertebrate species richness in ephemeral ponds.
- Experimental sites varied in canopy cover (open or closed) and presence/absence of salamander larvae. Species richness was highest in open sites and was best predicted by abiotic habitat variables like hydroperiod rather than biotic interactions.
- Competition from salamander larvae appeared to have little impact on species richness, possibly due to the highly disturbed nature of ephemeral ponds and low larval densities.
ATBI Mapping Program: Species Distribution Models for Great Smoky Mountains N...Tanner Jessel
ATBI Mapping Program: Where Do All These Species Live? – Tanner Jessel The ATBI not only focuses on scientific research and education, but also on conservation stewardship of the national park. One of the most valuable conservation questions it is answering is: Where do the thousands of species that call the Smokies "home" actually live? To date the ATBI not only has dot maps for almost all the species, but for those with enough (>30) point locations our partners at the University of Tennessee can produce "predictive models" of where they occur over the entire 800+ square mile park... an Atlas of Species!
Line × tester analysis for yield contributing morphological traits in Triticu...Innspub Net
The present study was carried out for the development of the water stress wheat cultivars with higher grain yield by studying the genetic basis of crucial morphological traits. Nine wheat genotypes were grouped into six lines and three testers and these parents were crossed line x tester fashion. Eighteen crosses including nine parents were planted in the field in randomized complete block design with three replications. Three drought tolerant varieties Chakwal-50, Chakwal-86 and Kohistan-97 were also sown to compare the results in water stress environment. Highest negative GCA effects were observed in WN-36 for plant height (-6.17) and flag leaf area (-1.53), while for peduncle length it was noted in 8126 lines (-1.15). Highest positive GCA effects were observed in WN-32 for a number of grains per spike (5.21), grain yield per plant (2.08) and for spikelet per spike (0.33), while for 8126 and WN-10 the number of tillers per plant (0.67) and spike length (0.25) was found, respectively. The crosses 9451 × WN-25, WN-36 × 8126, WN-10 × 8126 showed highest negative SCA effects for plant height (-8.06), flag leaf area (-2.89), and peduncle length (-2.05), respectively. Moreover, the cross combinations of WN-36 × WN-25, WN-32 × WN-25 and AARI-7 × 9526 showed positive SCA effects for number of tillers per plant (1.52), spike length (0.72) and number of spikelet per spike (0.84) respectively, while the interaction of WN-35 × 8126 crosses showed highest positive SCA effects for number of grains/spike (5.69) and grain yield/plant (2.75). The parental material used in this study and cross combinations obtained from these parents may be exploited in future breeding endeavors.
This document is the first progress report of Amelia Lamb's research on the effects of shrubs and understory annual plants on kangaroo rat species in a desert annual community. The report summarizes previous literature on positive plant interactions and the stress gradient hypothesis. It also describes the study site and species, and outlines the methods for surveys to examine animal activity along a shrub and annual plant gradient, and foraging experiments using giving-up density trials to study kangaroo rat foraging patterns. Current objectives include further analyzing pilot study data, and carrying out extensive field surveys and experiments in April and May.
This document summarizes a study on the mechanisms of resistance to the sorghum shoot fly, Atherigona soccata, in sorghum. The study evaluated different components of resistance (antixenosis, antibiosis, tolerance) in resistant and susceptible sorghum genotypes under field and greenhouse conditions. Key findings include: 1) Resistant genotypes experienced lower deadheart formation, produced more productive tillers, and insects fed on resistant genotypes had longer larval periods and lower survival rates. 2) Physico-chemical traits like leaf glossiness and trichome density were associated with resistance while chlorophyll content and leaf wetness were associated with susceptibility. 3) Deadheart formation, eggs on leaves, leaf gloss
L37 gedrag van planten, kan dat wel theo elzengaTycho Malmberg
Plants exhibit complex behaviors in response to environmental stimuli. They actively forage for resources like light, water, and nutrients through phenotypic plasticity rather than movement. Receptor proteins allow plants to sense myriad signals and integrate the information to determine adaptive responses. Competition between plants mimics behaviors seen in social insects as roots forage and compete for soil resources through self/non-self discrimination and communication between individuals. Parasitic plants like dodder exhibit targeted "hunting" behaviors in attaching to hosts through foraging decisions that maximize energy gain.
Presentation made by Andy Jarvis in the Latin American Congress of Chemistry on 30th September 2010, in the symposium on Biodiversity and Ecosystems: the role of the chemical sciences.
Bari a 2nd iwsrs conference - izmir - 29 april2014ICARDA
This document summarizes a symposium on predicting and locating sources of resistance to stripe rust in durum wheat genetic resources. It discusses using a Focused Identification of Germplasm Strategy (FIGS) approach to screen wheat genebank accessions based on environmental variables associated with traits of interest, like disease resistance. Models are developed to predict potential resistance in accessions based on climate data from collection sites. Results show the support vector machine, random forest, and neural network models accurately classified known resistant and susceptible accessions, with areas under the ROC curve of 0.72 to 0.74.
Community resistance to biological invasions : role of diversity and network ...Alison Specht
The presentation of the CESAB group LOLA-BMS at the 2016 french ecology conference in the FRB-CESAB session "Using a treasury of knowledge to tackle complex ecological questions." Presented by François Massol and Patrice David
This document discusses the use of pollen analysis to study past vegetation and climate changes. Key points include:
- Pollen grains can be used to identify plant species due to their unique morphology and are well-preserved in sediments.
- Pollen production varies among plant species and those dispersed by wind are overrepresented in sediments.
- Changes in pollen percentages over time are interpreted to reflect shifts in vegetation and climate based on plant ecological requirements and modern analogs.
- Other proxies like macrofossils provide direct plant evidence but are less widely available than pollen.
No 8. response of mukhikachu (colocasia esculenta l.) cv. bilashi to plant sp...PARTNER, BADC, World Bank
The document summarizes a study on the effect of different plant spacing on the growth, yield and storability of mukhikachu (Colocasia esculenta L.) cv. Bilashi. Four spacing treatments were tested: S1 (60 cm × 20 cm), S2 (60 cm × 30 cm), S3 (60 cm × 40 cm), and S4 (60 cm × 50 cm). Maximum individual corm weight, number of suckers per hill, yield of corms and cormels per hectare were obtained from S3 (60 cm × 40 cm) spacing. However, plant spacing did not significantly affect the storability of cormels. The study found that a spacing of
This document summarizes research on ranaviruses, which are pathogens that can cause disease outbreaks in amphibians, reptiles, and fish. Ranaviruses have been detected globally and can infect over 70 amphibian species from 14 families on 5 continents. Susceptibility and mortality from ranavirus infection varies between species and life stages. Some species may act as reservoirs or amplification hosts. There is evidence that ranaviruses can transmit between classes of vertebrates (e.g. from fish to amphibians). Stressors like temperature, pollution, and genetic isolation can increase susceptibility. Ranaviruses have been associated with local population declines and extirpations, especially of rare species.
This document describes techniques and procedures used in nematology laboratories in South Africa. It discusses nematode sampling methods, including sampling equipment, size and area, depth, and timing. Proper handling, labeling, transport, and storage of samples is also covered. Visual examination of plant material for nematode symptoms is described, such as root galls caused by root-knot nematodes or cysts from cyst nematodes. The document provides concise technical information on standard nematology laboratory practices.
Evolution of North American MicruracarusRachel Shoop
My research focuses on the evolution of North American water mites in the genus Arrenurus, Subgenus Micruracarus. In this presentation, I discuss why I chose to study these little known critters, and present some preliminary findings. Please contact me for more info.
This document summarizes a study on using cover crops to manage the root-knot nematode (Meloidogyne incognita) in yam production systems. Pot and field experiments tested the effect of 10 cover crops on M. incognita populations and yam tuber damage. Results showed that tagetes, crotalaria, and aeschynomene cover crops significantly reduced nematode densities and yam damage, while lablab, mucuna, and cowpea supported high nematode populations. The document concludes that tagetes, crotalaria, and aeschynomene should be incorporated into yam farming to control root-knot nematodes.
This document discusses various methods used to measure biodiversity, including biological sampling techniques to estimate species density and abundance. Some key methods mentioned are line transects, quadrats, capture-recapture, traps, aerial photographs, and counts of artifacts. It also discusses indices to quantify biodiversity, such as Simpson's Index and Shannon-Wiener Index, and gives examples of their calculation and interpretation. Finally, it covers topics like endemism levels in Australia and measures of extinction risk.
The population-level consequences of native and invasive herbivores for nativ...Kristen Sauby
We explored the joint effects of native and invasive insect herbivory on plant population growth using a set of closely interacting species: two species of native cacti (Opuntia) in Florida and two cactus moth species (the native Melitara prodenialis and the invasive South American Cactoblastis cactorum).
Native and Invasive Insect Herbivory and Precipitation Explain Variation in V...Kristen Sauby
This study examined the relative impacts of native and invasive insect herbivory and precipitation on vital rates of the endangered cactus Opuntia stricta. The researchers found that:
1) Native and invasive insect presence slightly negatively affected plant growth rate.
2) Native insect presence and larger plant size positively affected fruit production probability, while precipitation negatively affected it.
3) Precipitation and larger plant size positively affected fruit abundance, but invasive insect presence interacting with precipitation negatively affected it.
Cactoblastis cactorum - how big is the risk to native Opuntia?Kristen Sauby
The document summarizes research on the invasive cactus moth Cactoblastis cactorum and its impacts on native prickly pear cacti in Florida. Key findings include:
- The moth is widely distributed in Florida but primarily attacks two species of native prickly pear cacti.
- In plot surveys, the moth was found infesting 4% and 0.5% of plots with cacti, but only 0.2% of individual cacti.
- A plant demography study found 19% of cacti showed moth damage, but the presence of the moth was not a significant predictor of cactus mortality. The size of the cactus
This document provides an introduction to LaTeX, covering what LaTeX is, why you would want to use it, its document structure, and how to include math, R code/objects, and references. LaTeX is a programming language used to create consistently formatted documents across different document types. It allows for fancy fonts, automatic numbering, and embedding of other objects like figures, tables, and R code/outputs. The document structure in LaTeX includes the preamble, top matter, main text, appendices, bibliography, and comments.
This presentation introduces the basics of the R statistical language and provides information on best practices when using R. This was aimed to be accessible to beginners as well as those looking to improve their knowledge about R.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
ANAMOLOUS SECONDARY GROWTH IN DICOT ROOTS.pptxRASHMI M G
Abnormal or anomalous secondary growth in plants. It defines secondary growth as an increase in plant girth due to vascular cambium or cork cambium. Anomalous secondary growth does not follow the normal pattern of a single vascular cambium producing xylem internally and phloem externally.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
Nucleophilic Addition of carbonyl compounds.pptxSSR02
Nucleophilic addition is the most important reaction of carbonyls. Not just aldehydes and ketones, but also carboxylic acid derivatives in general.
Carbonyls undergo addition reactions with a large range of nucleophiles.
Comparing the relative basicity of the nucleophile and the product is extremely helpful in determining how reversible the addition reaction is. Reactions with Grignards and hydrides are irreversible. Reactions with weak bases like halides and carboxylates generally don’t happen.
Electronic effects (inductive effects, electron donation) have a large impact on reactivity.
Large groups adjacent to the carbonyl will slow the rate of reaction.
Neutral nucleophiles can also add to carbonyls, although their additions are generally slower and more reversible. Acid catalysis is sometimes employed to increase the rate of addition.
Unlocking the mysteries of reproduction: Exploring fecundity and gonadosomati...AbdullaAlAsif1
The pygmy halfbeak Dermogenys colletei, is known for its viviparous nature, this presents an intriguing case of relatively low fecundity, raising questions about potential compensatory reproductive strategies employed by this species. Our study delves into the examination of fecundity and the Gonadosomatic Index (GSI) in the Pygmy Halfbeak, D. colletei (Meisner, 2001), an intriguing viviparous fish indigenous to Sarawak, Borneo. We hypothesize that the Pygmy halfbeak, D. colletei, may exhibit unique reproductive adaptations to offset its low fecundity, thus enhancing its survival and fitness. To address this, we conducted a comprehensive study utilizing 28 mature female specimens of D. colletei, carefully measuring fecundity and GSI to shed light on the reproductive adaptations of this species. Our findings reveal that D. colletei indeed exhibits low fecundity, with a mean of 16.76 ± 2.01, and a mean GSI of 12.83 ± 1.27, providing crucial insights into the reproductive mechanisms at play in this species. These results underscore the existence of unique reproductive strategies in D. colletei, enabling its adaptation and persistence in Borneo's diverse aquatic ecosystems, and call for further ecological research to elucidate these mechanisms. This study lends to a better understanding of viviparous fish in Borneo and contributes to the broader field of aquatic ecology, enhancing our knowledge of species adaptations to unique ecological challenges.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Predicting the Distribution of the Invasive Cactus Moth, Cactoblastis cactorum, and its Major Host Plant, Opuntia stricta, in Florida
1. Predic'ng
the
Distribu'on
of
the
Invasive
Cactus
Moth,
Cactoblas)s
cactorum,
and
its
Major
Host
Plant,
Opun)a
stricta,
in
Florida
Kristen
E.
Sauby,
Mary
C.
Christman,
and
Robert
D.
Holt
Department
of
Biology
University
of
Florida
Ecological
Society
of
America
Annual
Mee'ng
Sacramento,
California
August
11,
2014
2. Florida
Opun)a
and
Their
Specialist
Insect
Herbivores
Invasive
Cactus
Moth,
Cactoblas)s
cactorum
Na've
Cactus
Moth,
Melitara
prodenialis
Na've
Cactus
Bug,
Chelinidea
vi7ger
Na've
Cactus
Scale,
Dactylopius
sp.
O.
stricta
O.
pusilla
O.
humifusa
var.
ammophila
3. The
invasive
cactus
moth,
Cactoblas)s
cactorum,
“blas'ng”
its
host
species,
Opun)a
stricta,
in
Florida
4. Background
• Opun%a
are
na&ve
to
the
New
World
(North
and
South
America)
• Including
the
phylogeny
and
“puta&ve
dispersal
pathways
of
Opun%a
clades”
(Majure
et
al.,
American
Journal
of
Botany,
2012)
5. The
Path
to
the
North
American
Introduc'on
First
introduced
into
Australia
to
control
invasive
cac&
1957
Early
1930s
1925
of
the
Invasive
Cactus
Moth
Approx.
na&ve
range
of
moth
6. Successful
Biological
Control
in
Australia
Before…
ARer.
“In
August
1930,
for
150
miles
[240
km]
along
the
river
the
pest
[O.
stricta]
was
in
its
full
vigour,
its
con&nuity
almost
unbroken
by
cleared
land;
the
pastoral
proper&es
had
been
overrun
and
mainly
deserted.”
• Quotes
from
Dodd
(1940)
• Photos
from
Osmond
et
al.
“…in
August
1932,
90
percent
of
the
[prickly]
pear
had
collapsed.
The
change
in
exactly
two
years
was
extraordinary.”
2008
(Journal
of
Experimental
Botany)
7. Distribu'on
of
the
Invasive
Cactus
Moth
in
the
Louisiana,
2009
Most
recent
detec&ons:
Jefferson,
Lafourche,
and
Terrebonne
Parishes,
Louisiana
(2009)
Southeastern
United
States
South
Carolina,
2004
First
detec'on,
Florida
Keys,
1989
Source:
USDA
APHIS,
h`p://www.aphis.usda.gov/plant_health/plant_pest_info/cactoblas&s/spread.shtml,
accessed
21
March
2009
NE
Florida,
2000
8. Ques'ons
• How
prevalent
is
the
invasive
cactus
moth
and
moth
damage?
• How
important
are
different
factors
in
structuring
varia&on
in
cactus
and
invasive
cactus
moth
occurrence?
– Abio&c
factors
(eleva&on)
– Bio&c
factors
(plant
density,
canopy
cover)
– Spa&al
factors
9. The
invasive
moth
is
found
primarily
on
O.
humifusa
var.
ammophila
and
O.
stricta
(Sauby
et
al.
2012)
10. Sampling
at
the
Guana
Tolomato
Matanzas
Na'onal
Estuarine
Research
Reserve
(GTMNERR)
• Plot
Surveys
• Plant
Surveys
11. • Set
Sampling
Scheme
–
Plot
Surveys
up
1-‐meter2
plots
according
to
a
stra&fied
random
adap&ve
cluster
sampling
scheme
1. Stra&fied
Random
Sampling
(SRSWOR):
plots
randomly
distributed
across
(a)
5
islands
and
(b)
two
habitat
patches
(524
plots)
2. Adap&ve
Cluster
Sampling:
If
a
plot
had
cac&,
adjacent
plots
were
also
surveyed
(c)
(829
plots)
• Surveyed
plots
at
least
twice
a
year
(May
2012
–
present)
• Then
aggregated
data
for
analysis
12. • Set
Sampling
Scheme
–
Plot
Surveys
up
1-‐meter2
plots
according
to
a
stra&fied
random
adap&ve
cluster
sampling
scheme
1. Stra&fied
Random
Sampling
(SRSWOR):
plots
randomly
distributed
across
(a)
5
islands
and
(b)
two
habitat
patches
(524
plots)
2. Adap&ve
Cluster
Sampling:
If
a
plot
had
cac&,
adjacent
plots
were
also
surveyed
(c)
(829
plots)
• Surveyed
plots
at
least
twice
a
year
(May
2012
–
present)
• Then
aggregated
data
for
analysis
(c)
13. • Set
Sampling
Scheme
–
Plot
Surveys
up
1-‐meter2
plots
according
to
a
stra&fied
random
adap&ve
cluster
sampling
scheme
1. Stra&fied
Random
Sampling
(SRSWOR):
plots
randomly
distributed
across
(a)
5
islands
and
(b)
two
habitat
patches
(523
plots)
2. Adap&ve
Cluster
Sampling:
If
a
plot
had
cac&,
adjacent
plots
were
also
surveyed
(c)
(824
plots)
• Surveyed
plots
at
least
twice
a
year
(May
2012
–
present)
• Aggregated
data
for
analysis
(c)
14. Sampling
Scheme
–
Plant
Surveys
• Mapped
and
marked
individual
cactus
plants
in
a
random
subset
of
plots
(287
plots;
1089
O.
stricta
and
1087
O.
pusilla
plants)
• Surveyed
all
at
least
twice
a
year
(Jan.
2013
–
present)
• Aggregated
data
for
analysis
15. Prevalence
of
Cac'
in
SRSWOR
Plots
• Propor&on
of
area
occupied
by
each
cactus
species
• O.
humifusa
var.
ammophila
was
rare
(found
in
only
1
plot)
500
400
300
200
100
Absent Present
Number of plots
O. stricta
500
400
300
200
100
O. pusilla
Absent Present
75/523
=
14.3%
45/523
=
8.6%
16. Sample
Size
of
Plots
with
Cac'
aRer
Adap've
Cluster
Sampling
• Increased
the
number
of
plots
with
cac&
1100
1000
900
800
700
600
500
400
300
200
100
Absent Present
Number of plots
O. stricta
1100
1000
900
800
700
600
500
400
300
200
100
O. pusilla
Absent Present
447/1347
=
33.2%
324/1347
=
24.1%
17. 400
350
300
250
200
150
100
50
Prevalence
of
the
Invasive
Cactus
Moth
Aggregated
Plot
Survey
Data
(May
2012
–
present)
Moth
Absent
Moth
Present
Number of plots
O. stricta
400
350
300
250
200
150
100
50
O. pusilla
Moth
Absent
Moth
Present
54/447
=
12.1%
1/324
=
0.31%
Presence
=
moth
larvae
and/or
eggs
were
found
at
least
once
Absence
=
moth
larvae
and/or
eggs
never
observed
18. 400
350
300
250
200
150
100
50
Prevalence
of
the
Invasive
Cactus
Moth
Moth
Absent
Moth
Present
Number of plots
O. stricta
400
350
300
250
200
150
100
50
O. pusilla
Moth
Absent
Moth
Present
1100
1000
900
800
700
600
500
400
300
200
100
Moth
Absent
Moth
Present
Number of plants
O. stricta
35/1089
=
3.2%
Aggregated
Plot
Survey
Data
(May
2012
–
present)
Aggregated
Plant
Survey
Data
(January
2013
–
present)
54/447
=
12.1%
1/324
=
0.31%
Presence
=
moth
larvae
and/or
eggs
were
found
at
least
once
Absence
=
moth
larvae
and/or
eggs
never
observed
19. Prevalence
of
Damage
from
Past
Moth
Infesta'ons
O. pusilla
54/449
=
12%
350
300
250
200
150
100
50
Damage
Absent
Damage
Present
Number of plots
O. stricta
350
300
250
200
150
100
50
Damage
Absent
122/324
=
38%
Damage
Present
334/447
=
75%
• An
es&mate
of
cumula&ve
prevalence
of
cactus
moths
• Many
plants
are
infested
at
some
point
in
their
lives
• Es&mates
may
be
biased
low
because
only
live
plants
are
surveyed
• Caveat:
damage
may
be
from
either
the
invasive
and/or
na&ve
cactus
moths
20. Hypothesized
Dynamics
of
Cactus
Moth
Invasion
N
cac&
t
invasive
cactus
moth
Current
state
of
invasion
21. Generalized
Linear
Mixed
Models
to
Explain
Paherns
of
O.
stricta
Occurrence
Analyzed
in
SAS
v.
9.4
using
GLIMMIX
procedure
Dependent
Variables
• O.
stricta
presence
Fixed
Effects
• Eleva&on
(meters)
• Vegeta&on
Class
(five
categories)
• Vegeta&on
Density
(scale
of
0
–
4)
• Detritus
Density
(scale
of
0
–
4)
• Canopy
(yes/no)
Random
Effects
• Habitat
Patch
• Network
(the
adap&ve
cluster
to
which
a
plot
belongs)
22. Results
-‐
Generalized
Linear
Mixed
Models
to
Explain
Paherns
of
Cactus
Occurrence
Tests
of
Fixed
Effects
Effect Es'mate St.
Error Pr
>
F
Canopy 0.17 0.33 0.5970
Vegeta&on
Class -‐ -‐ 0.0007
Vegeta&on
Density 0.38 0.12 0.0010
Detritus
Density 0.42 0.11 <.0001
Eleva&on
(m) 0.037 0.10 0.7153
23. Results
–
Rela'onship
Between
Vegeta'on
Class
and
O.
stricta
Occurrence
Least
Squares
Means
Vegeta'on
Class
Mean
Prob(Y=1)
Standard
Error
t
Value
Pr
>
|t|
Marsh
plants
0.0097
0.0081
-‐5.50
<.0001
Mixed
forbs
0.16
0.059
-‐3.78
0.0002
Overhanging
cedar/mixed
forbs
0.14
0.057
-‐3.83
0.0001
Palm/palme`o
0.00014
0.0022
-‐0.57
0.57
Shrubs/vines
0.083
0.039
-‐4.64
<.0001
24. Generalized
Linear
Mixed
Model
to
Explain
Paherns
of
Invasive
Cactus
Moth
Occurrence
on
O.
stricta
• Limited
analysis
to
plots
containing
O.
stricta
• Analyzed
in
SAS
v.
9.4
using
GLIMMIX
procedure
Dependent
Variable
• Invasive
Cactus
Moth
presence
Fixed
Effects
• O.
stricta
maximum
height
• O.
stricta
percent
cover
• Eleva&on
(meters)
• Vegeta&on
Class
(seven
categories)
• Vegeta&on
Density
(scale
of
0
–
4)
• Detritus
Density
(scale
of
0
–
4)
• Canopy
(yes/no)
Random
Effects
• Network
(the
adap&ve
cluster
to
which
a
plot
belongs)
• Did
NOT
include
Habitat
Patch
because
it
was
not
sta&s&cally
significant
in
a
model
with
only
random
effects
25. Results
-‐
Generalized
Linear
Mixed
Model
to
Explain
Paherns
of
Invasive
Cactus
Moth
Occurrence
on
O.
stricta
Effect
Es'mate
St.
Error
Pr
>
F
Canopy
0.21
0.7751
0.79
Vegeta'on
Class
-‐
-‐
0.52
O.
stricta
Height
0.042
0.016
0.011
O.
stricta
Percent
Cover
0.038
0.018
0.037
Eleva'on
0.23
0.094
0.013
Detritus
0.046
0.22
0.84
26. Conclusions
• Abio&c
and
bio&c
factors
can
be
used
to
explain
pa`erns
of
cactus
and
cactus
moth
occurrence
O.
stricta
occurrence
• Posi&ve
rela&onship
with
detritus
and
vegeta&on
density
• Significant
varia&on
among
vegeta&on
classes
27. Conclusions
Invasive
cactus
moth
occurrence
• Cumula&ve
damage
is
much
greater
than
present
rates
of
infesta&on
• Rare
on
O.
pusilla
• Posi&vely
related
to
O.
stricta
height
and
percent
cover
as
well
as
eleva&on
Spa&al
factors
• Habitat
patch
and
Network
included
in
models
of
cactus
occurrence
as
random
effects
28. Invasive
Species
Management
• Important
to
consider
the
rela&ve
threat
of
the
species
• Important
to
account
for
spa&al
varia&on
in
risk
of
invasion
and
costs
of
surveillance
(Epanchin-‐Niell
et
al.,
Ecol.
Le;.,
2012)
29. Future
Work
• Assess
temporal
and
spa&al
autocorrela&on
in:
– the
dynamics
of
cactus
and
cactus
moth
occupancy
• Assess
threat
of
the
invasive
cactus
moth
to
cac&
using
demographic
models
30. Acknowledgments
University
of
Florida
• Michael
Barfield
• James
Nifong
• Doria
Gordon
• Robert
Fletcher
• Jose
Miguel
Poncianco
• Jake
Ferguson
• Rosana
Zenil-‐Ferguson
• Polly
Harding
(pictured)
Feel
free
to
contact
me
at
ksauby@ufl.edu
GTMNERR
• Ka'e
Petrinec
• Mah
Welsh