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Effect Of The Herbivorous Channel Clinging Crab (Mithrax Spinosissimus) On Patch Reef Algal Communities In The Florida Keys, Florida (Usa), Angela M. Mojica Osorio Jul 2009

Effect Of The Herbivorous Channel Clinging Crab (Mithrax Spinosissimus) On Patch Reef Algal Communities In The Florida Keys, Florida (Usa), Angela M. Mojica Osorio

Biological Sciences Theses & Dissertations

Coral reefs worldwide are undergoing dramatic habitat modification from coral to macroalgal dominance due to water pollution, coral diseases, global. warming, and the loss of herbivores. This phase-shift bas been particularly severe on Caribbean reefs due in large measure to the decline of piscine and echinoderm grazers, whose presence appears crucial for stemming the decline of coral reefs and enhancing their resilience. Virtually unknown, however, is the role of other macrograzers in coral reef ecosystems. This is the first study to examine the feeding ecology and grazer effect of the herbivorous West Indian spider crab (Mithrax spinosissimus) on inshore patch …


Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Annual Progress Report, Period Covering July 1, 2008 - June 30, 2009, Margaret N. Rees Jun 2009

Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Annual Progress Report, Period Covering July 1, 2008 - June 30, 2009, Margaret N. Rees

Get Outdoors Nevada

  • From July 1, 2008 to June 30, 2009 the Volgistic database has increased the number of records by 20% containing a total 6,226 records at the end of this period.
  • Website activity this year averaged 63,590 hits per month, with an average of 5,290 pages viewed per month.
  • The IVP team presented a summary of their accomplishments to the SNAP board.
  • The team attended 13 community outreach events resulting in 2,501 direct contacts and 394 new mailing list records.
  • How to Succeed with Volunteers training was held for SNAP personnel.
  • The IVP team met with four SNAP teams to develop …


Natural Life Histories Of Alaska Colias (Lepidoptera: Pieridae), Jack L. Harry Jun 2009

Natural Life Histories Of Alaska Colias (Lepidoptera: Pieridae), Jack L. Harry

The Taxonomic Report of the International Lepidoptera Survey

Eight species of the genus Colias of Alaska were studied during the years of 2005, 2006, and 2007. Natural life histories were determined, immature stages described, measured, and photographed. Scanning Electron Microscope (SEM) pictures of the micropyle of five species are included.


Phylogenetic Analyses Reveal Monophyletic Origin Of The Ergot Alkaloid Gene Dmaw In Fungi, Miao Liu, Daniel G. Panaccione, Christopher L. Schardl Jun 2009

Phylogenetic Analyses Reveal Monophyletic Origin Of The Ergot Alkaloid Gene Dmaw In Fungi, Miao Liu, Daniel G. Panaccione, Christopher L. Schardl

Plant Pathology Faculty Publications

Ergot alkaloids are indole-derived mycotoxins that are important in agriculture and medicine. Ergot alkaloids are produced by a few representatives of two distantly related fungal lineages, the Clavicipitaceae and the Trichocomaceae. Comparison of the ergot alkaloid gene clusters from these two lineages revealed differences in the relative positions and orientations of several genes. The question arose: is ergot alkaloid biosynthetic capability from a common origin? We used a molecular phylogenetic approach to gain insights into the evolution of ergot alkaloid biosynthesis. The 4-γ,γ-dimethylallyltryptophan synthase gene, dmaW, encodes the first step in the pathway. Amino acid sequences deduced …


A New Brevicipitid Species (Brevicipitidae: Callulina) From The Fragmented Forests Of The Taita Hills, Kenya, Simon P. Loader, G. John Measey, Rafael O. De Sá, Patrick K. Malonza Jun 2009

A New Brevicipitid Species (Brevicipitidae: Callulina) From The Fragmented Forests Of The Taita Hills, Kenya, Simon P. Loader, G. John Measey, Rafael O. De Sá, Patrick K. Malonza

Biology Faculty Publications

A new species Callulina dawida is described from the Taita Hills, Kenya. It is distinguished from other members of the genus on the basis of the degree of digital expansion. The species further differs from other members of the genus based on molecular sequence comparisons and on its call. The morphological variation in the new species is described, including a comparison of internal and external characters and sexual dimorphism with other species of Callulina. The conservation status of the species, on the basis of its restricted distribution and land use changes in the area, is considered to be of …


Purple Martin, Progne Subis, In San Luis Obispo County Riparian Habitat: Presence, Persistence, Nesting, Brooding And Reproductive Success, Shannon Eileen Murphy Jun 2009

Purple Martin, Progne Subis, In San Luis Obispo County Riparian Habitat: Presence, Persistence, Nesting, Brooding And Reproductive Success, Shannon Eileen Murphy

Biological Sciences

The State of California, as of 2002, identified the Purple Martin as a bird species of Special Concern (Airola et al., 2003). These migrants were historically found in a unique habitat in Central California; nesting in natural cavities of Western Sycamores within Riparian Habitats. I am proposing that Purple Martins still successfully nest and brood young in this unique habitat in San Luis Obispo County. The primary study site is in Atascadero where Highway 41 meets San Gabriel Road and San Gabriel Road crosses Atascadero creek. The secondary site is Highway 58 in Santa Margarita where the highway crosses the …


Loss Of Shoaling Preference For Familiar Individuals In Captive-Reared Crimson Spotted Rainbowfish Melanotaenia Duboulayi, Erin Kydd, Culum Brown Jun 2009

Loss Of Shoaling Preference For Familiar Individuals In Captive-Reared Crimson Spotted Rainbowfish Melanotaenia Duboulayi, Erin Kydd, Culum Brown

Sentience Collection

Captive-reared rainbowfish Melanotonia duboulayi showed no preference for familiar individuals in an experiment examining shoaling preferences. Fortnightly re-examination of the shoaling preferences of the captive-reared population showed that the lack of preference for familiar individuals did not alter over an 8 week period. The same experiment performed on laboratory-reared offspring raised in isolated groups for 8 months since hatching also showed no preference for shoals consisting of familiar individuals. In contrast, trials performed on a wild population of M. duboulayi found a strong preference for familiar shoalmates, a result that is consistent with previous studies. The lack of shoaling preferences …


Barrow Island Ute Guide - Non-Indigenous Insects, Spiders And Snails, Mike Grimm, Kristofer Collett, Peter Davis, Marc Widmer, Andras Szito, Rob Emery, Peter Mangano Jun 2009

Barrow Island Ute Guide - Non-Indigenous Insects, Spiders And Snails, Mike Grimm, Kristofer Collett, Peter Davis, Marc Widmer, Andras Szito, Rob Emery, Peter Mangano

Biosecurity published reports

Barrow Island, the second largest island in Western Australia, is a Class A Nature Reserve and home to a variety of rare and endangered fauna and flora, some of which occur nowhere else. The island lies about 70 km off the north-west coast of Western Australia and 150 km west of Karratha.

Oil discoveries in the 1960s and the development of massive Northwest Shelf gas reserves since the 1990s made Barrow Island an important site for these industries. Strict environmental and quarantine conditions are placed on industry seeking permits to drill oil wells and construct gas processing plants. Oil production …


Modeling And Analysis Of The Spread Of Japanese Encephalitis With Environmental Effects, Ram Naresh, Surabhi Pandey Jun 2009

Modeling And Analysis Of The Spread Of Japanese Encephalitis With Environmental Effects, Ram Naresh, Surabhi Pandey

Applications and Applied Mathematics: An International Journal (AAM)

A nonlinear mathematical model for the spread of Japanese Encephalitis, caused by infected mosquito feeding on susceptible human population incorporating demographic and environmental factors is proposed and analyzed. In the modeling process, it is assumed that the growth rates of reservoir animal population and vector mosquito population are enhanced due to environmental discharges caused by human population related factors. The model is analyzed by stability theory of differential equations and computer simulation. Both the disease-free and the endemic equilibria are found and their stability is investigated. It is found that whenever the disease-free equilibrium is locally asymptotically stable, the endemic …


The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind Jun 2009

The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind

Master's Theses

To gain a better understanding of the role of steroid hormones in vertebrate reproduction, we quantified steroid hormone concentrations in a free ranging population of the Northern Pacific rattlesnake, Crotalus oreganus. Plasma steroid hormone concentrations were quantified for both male and female snakes throughout the active season (Mar-Oct). We measured testosterone (T), 5α-dihydrotestosterone (DHT), and corticosterone (B) concentrations in male and female snakes. 17β-estradiol (E2) and progesterone (P) were measured in females only. We also observed breeding behaviors (e.g. consortship, courtship, and copulation) in the field and measured testis and follicle size in male and female snakes from museum collections. …


Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas Jun 2009

Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas

Master's Theses

This study examined the diet composition of ninety-nine Sacramento pikeminnow (150-410 mm [5.9-16 in] fork length [FL]) collected from the upper and lower main stem of Chorro Creek, Morro Bay Watershed, California in 2006. The goal of this study was to characterize the spatial and seasonal variability in the diet of Sacramento pikeminnow within Chorro Creek and to determine what proportion of the diet is represented by rainbow trout (Oncorhynchus mykiss) and their anadromous form (steelhead). Prey was identified in 88% of the samples collected in the early season and 84% of the samples collected in the late season. Fish …


Temporal Shifts In Demography And Life History Of An Anadromous Alewife Population In Connecticut, Justin P. Davis, Eric T. Schultz May 2009

Temporal Shifts In Demography And Life History Of An Anadromous Alewife Population In Connecticut, Justin P. Davis, Eric T. Schultz

EEB Articles

Populations of anadromous alewives (Alosa pseudoharengus) are declining throughout much of their range, particularly in southern New England where fishery moratoriums have recently been instituted in three states. The alewife run at Bride Brook, a coastal stream in East Lyme, Connecticut, was studied from 2003-06 to assess shifts in demography and life history. Annual censuses of abundance, along with sampling for size, age, and spawning history structure were conducted. These data were compared to similar data in 1966-67 at this site. Recent alewife runs at Bride Brook featured lower abundance and younger, smaller fish that were less likely to be …


Time Series Observations Of Species Composition And Behavioral Interactions Of Fish At An Ocean Observatory Off The Coast Of Georgia, Amy E. Paquette May 2009

Time Series Observations Of Species Composition And Behavioral Interactions Of Fish At An Ocean Observatory Off The Coast Of Georgia, Amy E. Paquette

Honors Scholar Theses

The use of ocean observatories is expanding with the potential for collecting serial data with high temporal resolution at multiple sites within an ecosystem. Integration of underwater video cameras in observatory systems allow observation of vagile species and are useful tools for observing variations in behavior over time. In order to assess the utility of using video records for time series behavioral data I analyzed video records from an observatory site in the South Atlantic Bight (SAB) off the Coast of Georgia collected during the month of November in 2000, 2002 and 2004. Data were used to quantify annual variation …


Modeling Parasitism Rate And Parasitism Risk: An Illustration Using A Colonially Nesting Songbird, The Red-Winged Blackbird Agelaius Phoeniceus, Max Post Van Der Burg, Larkin A. Powell, Andrew J. Tyre May 2009

Modeling Parasitism Rate And Parasitism Risk: An Illustration Using A Colonially Nesting Songbird, The Red-Winged Blackbird Agelaius Phoeniceus, Max Post Van Der Burg, Larkin A. Powell, Andrew J. Tyre

School of Natural Resources: Faculty Publications

Ornithologists interested in the drivers of nest success and brood parasitism benefit from the development of new analytical approaches. One example is the development of so-called “log exposure” models for analyzing nest success. However, analyses of brood parasitism data have not kept pace with developments in nest success analyses. The standard approach uses logistic regression which does not account for multiple parasitism events, nor does it prevent bias from using observed proportions of parasitized nests. Likewise, logistic regression analyses do not capture fine scale temporal variation in parasitism. At first glance, it might be tempting to apply log exposure models …


Potential For Introduced-Range Expansion Of Chinese Tallow Tree (Triadica Sebifera) In The Southeastern United States, Isaac Park May 2009

Potential For Introduced-Range Expansion Of Chinese Tallow Tree (Triadica Sebifera) In The Southeastern United States, Isaac Park

All Theses

The potential for populations of invasive plants to differ in their response to stressful environmental conditions or in their invasiveness is an underexplored issue in determining introduced species' range limits. Introduced genotypes might differ in their response to freezing temperatures, soil type, or differing biotic factors within their introduced range. We examined the potential of Chinese tallow tree seeds (Triadica sebifera (L.) Small) collected from two genetically distinct areas of its introduced range in the United States (North Carolina and South Carolina) as well as from the northern and southern portions of its native range in China to germinate and …


The Geographic Distribution Of Polyploidy In A Pacific Northwest Plant, Megan A. Larson May 2009

The Geographic Distribution Of Polyploidy In A Pacific Northwest Plant, Megan A. Larson

Renée Crown University Honors Thesis Projects - All

Polyploidy is an important evolutionary mechanism of speciation in plants. Because polyploids may evolve cryptically, there can be several levels of ploidy in a species. The distribution of polyploid species is the first step in understanding the role of polyploidy in plant speciation. I examined the geographic distribution of polyploidy in Heuchera cylindrica (Saxifragaceae) by using flow cytometry to determine the ploidy level of 595 individuals from 39 populations spread across the geographic range of the species. Only single cytotype populations of diploids or tetraploids were found, and no triploids were observed. In contrast to other studies of polyploid distribution, …


Identification Of Arid Soil Inducible Genes In Pseudomonas Fluorescens Strain Pf0-1, Katila Pipitone May 2009

Identification Of Arid Soil Inducible Genes In Pseudomonas Fluorescens Strain Pf0-1, Katila Pipitone

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis contains three major sections: introduction, literature review and the project entitled: 'Identification of Arid Soil Inducible Genes in Pseudomonas fluorescens Strain Pf0-1'. The introduction section describes a general background, the current and potential applications of P. fluorescens and the main goal of this dissertation. The literature review chapter discusses two main areas. The first area offers insights about different types of in vivo expression technology (IVET) as a tool in gene identification. This section also describes the limitations of IVET, as well as the benefits over other methods for gene identification. The second part of the literature review …


Distribution And Site Selection Of Le Conte's And Crissal Thrashers In The Mojave Desert: A Multi-Model Approach, Dawn Marie Fletcher May 2009

Distribution And Site Selection Of Le Conte's And Crissal Thrashers In The Mojave Desert: A Multi-Model Approach, Dawn Marie Fletcher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Information on the distribution and habitat requirements of a species are critical components to the development of meaningful conservation plans. Such knowledge, however, is particularly difficult to obtain for species that are elusive and occur at low densities, such as the Le Conte's ( Toxostoma lecontei ) and Crissal (Toxostoma crissale ) thrashers. In association with a regional conservation plan, I evaluated the distribution and habitat selection of these thrashers within Clark County, Nevada in the eastern Mojave Desert. I used a call-broadcast approach to sample 432 stratified random locations, detecting Le Conte's thrashers at 45 locations and Crissal …


Water Quality Changes In A Constructed Wetland At The Springs Preserve In Las Vegas, Nevada, Aaron Mathis Miller May 2009

Water Quality Changes In A Constructed Wetland At The Springs Preserve In Las Vegas, Nevada, Aaron Mathis Miller

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Springs Preserve near downtown Las Vegas, Nevada contains a seven-acre constructed wetland. Springs Preserve managers are planning to use water from the constructed wetland to irrigate creeks immediately north of the wetland. These creeks will be used by a variety ofaquatic wildlife, including endangered amphibians sensitive to harmful metalloids, such as selenium, lead, and arsenic.

In an attempt to answer toxicological questions about contaminant concentrations in the constructed wetland, three metals and metalloids (selenium, arsenic, and lead), two nutrients (nitrogen and phosphorus), and the major ionic species were analyzed at four sampling locations for aqueous concentrations, in two separate …


Behavioral Interactions Of Breeding Bald Eagles (Haliaeetus Luecocephalus) At Lake Cascade, Idaho, Scott Allen Kimball May 2009

Behavioral Interactions Of Breeding Bald Eagles (Haliaeetus Luecocephalus) At Lake Cascade, Idaho, Scott Allen Kimball

Boise State University Theses and Dissertations

During the 2000 and 2001 breeding seasons I studied the behavioral inter- and intra-specific interactions of Bald Eagles (Haliaeetus leucocephalus) breeding at Lake Cascade, Idaho. In the first chapter, I describe the relationships between an increase in population density and home range and foraging habitat use by Bald eagles. In the second chapter, I describe the relationship between aggressive interactions and reproductive success, as measured by number of nestlings fledged and nestling weight.

Because home range and foraging habitat use show temporal variability, I compared breeding home ranges and foraging habitat use of Bald Eagles at Lake Cascade, Idaho in …


Goatsrue (Galega Officinalis) Seed Biology, Control, And Toxicity, Michelle Oldham May 2009

Goatsrue (Galega Officinalis) Seed Biology, Control, And Toxicity, Michelle Oldham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Goatsrue is an introduced perennial plant that has proven to have great invasive potential, leading to its classification as a noxious weed in many states and at the federal level. This research focused on seed biology, herbicide control, and toxic dynamics of goatsrue. Physical dormancy of mature goatsrue seed was tested through scarification using sulfuric acid with exposures of up to 60 minutes resulting in 100% germination. Comparison of dormancy for 26-year-old and 6-month-old goatsrue seed indicated aged seeds had reduced dormancy levels compared to newly harvested seeds, but had similar viability. Goatsrue seedling emergence was inversely related to burial …


Roosting And Foraging Ecology Of Forest Bats In The Southern Appalachian Mountains, Joy O'Keefe May 2009

Roosting And Foraging Ecology Of Forest Bats In The Southern Appalachian Mountains, Joy O'Keefe

All Dissertations

Although most bats in the southeastern United States depend on forests for roosting and foraging, we know little about the ecological requirements of bats that live in this region. The objective of this study was to use radio telemetry, acoustic sampling, Akaike's information theoretic procedures, occupancy modeling, and discriminant function analyses to: 1) examine multi-scale roost-site selection for three forest bat species [eastern pipistrelles (Perimyotis subflavus), eastern red bats (Lasiurus borealis), and northern long-eared bats (Myotis septentrionalis)], 2) test the effects of timber harvest on bat foraging ecology in riparian areas, and 3) compare and relate methods of assessing vegetative …


Effects Of The Polycyclic Musk Hhcb On Individual- And Population-Level Endpoints In Potamopyrgus Antipodarum, Signe Pedersen, Henriette Selck, Daniel Salvito, Valery E. Forbes May 2009

Effects Of The Polycyclic Musk Hhcb On Individual- And Population-Level Endpoints In Potamopyrgus Antipodarum, Signe Pedersen, Henriette Selck, Daniel Salvito, Valery E. Forbes

Valery Forbes Publications

Although the polycyclic musk 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[γ]-2-benzopyran (HHCB) is frequently detected in aquatic sediments, very little is known about its effects on sediment-feeding organisms. Effects of sediment-associated HHCB on growth, feeding rate, survival and reproduction in the gastropod Potamopyrgus antipodarum were measured in the laboratory. Snails were exposed to six nominal HHCB concentrations: 0, 0.1, 1, 10, 30 and 100 μg g−1 dry weight (dw) sediment. Adult survival and growth were not affected by HHCB. However, juvenile growth and survival, reproduction, time to first reproduction and adult feeding rate were more sensitive endpoints and declined with increasing HHCB concentration. Individual-level endpoints for …


Endurance And Exercise Physiology In Urosaurus Ornatus: Sex And Morph Differences?, Elizabeth Christine Foulkes May 2009

Endurance And Exercise Physiology In Urosaurus Ornatus: Sex And Morph Differences?, Elizabeth Christine Foulkes

All-Inclusive List of Electronic Theses and Dissertations

Locomotory performance has been the focus of many ecological and evolutionary studies, and lizards have been a model system. While several studies have demonstrated interspecific differences in performance, few have examined intraspeciflc variation in performance and the suites of underlying physiological traits in tree lizards ( Uro.,·aurns ornatus) a species with alternative reproductive tactics that show variation in spatial use patterns. To assess the functional ecology of movement behaviors of male morphs and or females, I examined variation in exertion, plasma metabolites, plasma steroid hormones, and muscle fiber types in ornate tree lizards ( Urosaurus ornalus). In my study population, …


White-Tailed Deer Management Plan, Robert B. Gordon Natural Area Of West Chester University, Chester County, Pennsylvania, Gino J. D’Angelo Apr 2009

White-Tailed Deer Management Plan, Robert B. Gordon Natural Area Of West Chester University, Chester County, Pennsylvania, Gino J. D’Angelo

Deer and Non-native Invasive Plant Impact Study Documents

No abstract provided.


Miti Iko Wapi Ii ?, Taylor Tully Apr 2009

Miti Iko Wapi Ii ?, Taylor Tully

Independent Study Project (ISP) Collection

Vegetative communities within the savannah ecosystem oscillate between grassland and woodland states. Research has found that ecological perturbations resulting from elephants, fire, other herbivores and humans have a significant influence on the oscillation of vegetative communities. Understanding these forces and how they interplay to influence vegetative dynamics states is essential to a developing any effective conservation management program. A previous study, in 2003, was conducted to establish baseline data on vegetative community structure, elephant damage and fire damage within Ndarakwai Ranch. (Hamilton and Downing 2003). However, the study drew few definitive conclusions and suggested further research. This study was a …


Spring 2009, Nsu Oceanographic Center Apr 2009

Spring 2009, Nsu Oceanographic Center

Currents

No abstract provided.


Plant Defense: A Pre-Adaptation For Pollinator Shifts, Justen B. Whittall, Matthew L. Carlson Apr 2009

Plant Defense: A Pre-Adaptation For Pollinator Shifts, Justen B. Whittall, Matthew L. Carlson

Biology

No abstract provided.


Fisheries Occasional Publication No. 66 - Scientific Review Of The West Coast Demersal Scalefish Fishery, Western Australia, Michael O'Neill, Department Of Fisheries Western Australia Apr 2009

Fisheries Occasional Publication No. 66 - Scientific Review Of The West Coast Demersal Scalefish Fishery, Western Australia, Michael O'Neill, Department Of Fisheries Western Australia

Fisheries Occasional Publications

In December 2008 the Hon Norman Moore MLC, Minister for Fisheries Western Australia appointed two independent experts to assess separately 1) the validity of scientific advice to management and 2) options to manage recreational fishing of west coast demersal scalefish. The following review (1) assesses the validity of research outlining the status of baldchin groper (Choerodon rubescens), West Australian dhufish (Glaucosoma hebraicum) and snapper (Pagrus auratus) as described in the terms of reference. In addition to the terms of reference, an opinion was requested regarding the current appropriateness of the research advice (Wise et al 2007) and the resulting management …


Comparative Ecology And Conservation Status Of Procambarus (Pennides) Gibbus And Procambarus (Pennides) Versutus In Marion County, Georgia, Joann Chadwick Apr 2009

Comparative Ecology And Conservation Status Of Procambarus (Pennides) Gibbus And Procambarus (Pennides) Versutus In Marion County, Georgia, Joann Chadwick

Theses and Dissertations

Two crayfish species, whose conservation status was of concern, Procambarus (Pennides) gibbus Hobbs and Procambarus (Pennides) versutus Hagen, and one relatively common crayfish, Procambarus (Pennides) spiculifer LeConte were studied at nine creek sites in Marion County, Georgia. Major objectives of the yearlong study were to 1) compare the habitats of these species, looking for environmental differences that might account for their isolated distributions within the county and 2) assess the current conservation status of P. gibbus and P. versutus. Each study site was characterized by a one-time assessment of floodplain width, stream width, water velocity, stream depth and assessment of …