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Full-Text Articles in Geology

Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele Jun 2003

Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele

Geology Faculty Publications and Presentations

This report provides a rationale for the advances in instrumentation and understanding needed to assess claims of ancient and extraterrestrial life made on the basis of morphological biosignatures. Morphological biosignatures consist of bona fide microbial fossils as well as microbially influenced sedimentary structures. To be recognized as evidence of life, microbial fossils must contain chemical and structural attributes uniquely indicative of microbial cells or cellular or extracellular processes. When combined with various research strategies, high-resolution instruments can reveal such attributes and elucidate how morphological fossils form and become altered, thereby improving the ability to recognize them in the geological record …


Studies On Benthic Denitrification In The Chwaka Bay Mangrove Sediments, Zanzibar, Sm Mahommed, Rw Johnstone Nov 2002

Studies On Benthic Denitrification In The Chwaka Bay Mangrove Sediments, Zanzibar, Sm Mahommed, Rw Johnstone

Tanzania Journal of Science

Denitrification was measured at three sites in a narrow tidal creek in the Chwaka mangrove ecosystem. Denitrification arising from water column nitrate (Dw) was low (< 0.1μM Nm-2h-1) and there was little spatial and seasonal variation in Dw rates in the creek. Coupled nitrification-denitrification (Dn) was found to be low, but within the range measured in other mangrove sediments. Average values ranged from 0.01 to 0.45 μM Nm-2h-1 and showed strong spatial variations. The low denitrifcation rates observed in the creek were possibly as a result of the low availability of NO3 and high C:N values of the organic matter in the sediment. Spatial variations in denitrification rates were due to variations in concentration levels of organic matter and possibly to disproportionate competition for inorganic nitrogen between denitrifiers and benthic autotrophs among sites. There were no seasonal differences in denitrification rates. Results from the present study suggest that sediment denitrification does not play a major role as a sink for N in this ecosystem


Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock Aug 2002

Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock

UNLV Theses, Dissertations, Professional Papers, and Capstones

Five geomorphic surfaces present in the northern Pahranagat Valley, Lincoln County, Nevada range in age from Early Pleistocene to Recent (Q1-Q5) and vary in clast lithology from dolomite to volcanic tephras. Two chronosequences and 5 lithosequences were compared to evaluate micro and macromorphic characteristics and development of soil pendants. This study presents a new interpretation for soil pendant development. Key features observed in the Pahranagat Valley pendants provide evidence for precipitation at the clast-pendant contact suggesting that newer deposits are not always found at the pendant terminus as other studies have assumed. These features include a void at the clast-pendant …


Bulletin No. 37: Living Resources And Habitats Of The Lower Connecticut River, Glenn D. Dreyer, Marcianna Caplis Dec 2001

Bulletin No. 37: Living Resources And Habitats Of The Lower Connecticut River, Glenn D. Dreyer, Marcianna Caplis

Bulletins

No abstract provided.


Effect Of The Direction Of The Blast On Vegetation Recovery Within The Zone Of Devastation Created By The May 18, 1980 Eruption Of Mount St. Helens, Washington, Dmitri Barkovsky Aug 2000

Effect Of The Direction Of The Blast On Vegetation Recovery Within The Zone Of Devastation Created By The May 18, 1980 Eruption Of Mount St. Helens, Washington, Dmitri Barkovsky

All-Inclusive List of Electronic Theses and Dissertations

A number of different remote sensing techniques were used to analyze Landsat TM image data in order to study vegetation recovery patterns at three locations within the zone of devastation of Mount St. Helens (MSH). Prior to the May 18, 1980 eruption, the vegetation in the area ofMSH was characterized by mature coniferous forest disturbed only by a few clearcuts, according to analysis of Landsat MSS data. As a result of the MSH eruption, more than 600 sq. km of the area predominantly north of the volcano were severely devastated by a number of volcanic events such as phreatic explosions, …


The Age Of The Woolly Rhino From Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Derek C. Ford Apr 2000

The Age Of The Woolly Rhino From Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Derek C. Ford

WM Keck Science Faculty Papers

The Dream Cave woolly rhinoceros, Coelodonta antiquitatis, is a "classic" specimen of a "cold-stage" fossil fauna from central England. The find was illustrated and described by Dean William Buckland in his seminal tome Reliquiae Diluvianae (1823) during the first half of the 19th century, and made a significant contribution to the development of Buckland's views on the origin of extinct and extirpated fossil vertebrates. The report presents the first, albeit indirect, radiometric dates on the specimen, and argues that the animal fell into the cave just before 37,000 years BP, during the middle of Marine Isotope Stage 3 Interstadial (41 …


Reflections Of A Naturalist: Papers Honoring Professor Eugene D. Fleharty, Jerry R. Choate Jan 2000

Reflections Of A Naturalist: Papers Honoring Professor Eugene D. Fleharty, Jerry R. Choate

Fort Hays Studies Series

Science and academia tend to be dominated by persons who are utterly brilliant, or who are proficient at self-promotion, or who are willing to sacrifice their personal lives and work twice as hard as their peers, or who exhibit some combination of these attributes. Occasionally, however, someone comes along who is just "ordinary" compared with academic overachievers but whose accomplishments far exceed reasonable expectations. Eugene D. Fleharty is such a person. Although he is extraordinarily bright, few would describe him as utterly brilliant. He has never been inclined to "toot his own horn" or otherwise promote himself. And, although he …


Viability Of Piping Plover Charadrius Melodus Metapopulations, Jonathan H. Plissner, Susan M. Haig Jan 2000

Viability Of Piping Plover Charadrius Melodus Metapopulations, Jonathan H. Plissner, Susan M. Haig

United States Geological Survey: Staff Publications

The meta-population viability analysis package, vortex, was used to examine viability and recovery objectives for piping plovers Charadrius melodus, an endangered shorebird that breeds in three distinct regions of North America. Baseline models indicate that while Atlantic Coast populations, under current management practices, are at little risk of near-term extinction, Great Plains and Great Lakes populations require 36% higher mean fecundity for a significant probability of persisting for the next 100 years. Meta-population structure (i.e. the delineation of populations within the meta-population) and inter-population dispersal rates had varying effects on model results; however, spatially-structured meta-populations exhibited lower viability than …


A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry Jan 1999

A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The nature of the contribution of the various types of algae to sedimentary organic matter continues to be a topic of research interest. Crustose red algae have however received less attention than other types. The fossil calcareous red algae (Rhodophyta) analyzed in this study are two relatively unrecrystallized specimens of Parachaetetes (Family Solenoporacea) from the lower part of the Ste. Genevieve Formation (Carboniferous, Visean) in Union County, Illinois, USA. They occurred in the patch reef phase of a small carbonate mudmound-patchreef. The three modern specimens (collected and identified by F. Collier) are the crustose algae Lithothamnion, Clathromorphum and Phymatolithon …


New Caribbean Locality For The Extinct Great White Shark Carcharodon, Clare Flemming, Donald A. Mcfarlane Dec 1998

New Caribbean Locality For The Extinct Great White Shark Carcharodon, Clare Flemming, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Carcharodon is represented by a single upper tooth (Fig. 1) which we extracted from the eroding Pliocene limestone wall, some six meters above the floor at the northern end of Darby Sink. Much of the tooth is missing, but the remaining portion includes features diagnostic of this genus. The tooth conforms in size and morphology to Carcharodon megalodon (Agassiz, 1843), an extinct great white shark.


A Second Pre-Wisconsinan Locality For The Extinct Jamaican Rodent, Clidomys (Rodentia: Heptaxodontidae), Donald A. Mcfarlane, Joyce Lundberg, Clare Flemming, Ross D. E. Macphee, Stein-Erik Lauritzen Dec 1998

A Second Pre-Wisconsinan Locality For The Extinct Jamaican Rodent, Clidomys (Rodentia: Heptaxodontidae), Donald A. Mcfarlane, Joyce Lundberg, Clare Flemming, Ross D. E. Macphee, Stein-Erik Lauritzen

WM Keck Science Faculty Papers

Clidomys is the most distinctive but least well known member of the late Quaternary terrestrial mammal fauna of Jamaica. Here we report the second dated locality for this genus. The Illinoisan age we report further strengthens arguments we have made elsewhere, that Clidomys represents an early - probably pre-Wisconsinan - extinction that contrasts with the growing record of Holocene extinctions in the Antilles.


The Physical And Hydrological Characteristics Of A South Coast Sandplain Site : East Howick Site Survey, Robert Anthony Sudmeyer Jan 1998

The Physical And Hydrological Characteristics Of A South Coast Sandplain Site : East Howick Site Survey, Robert Anthony Sudmeyer

Resource management technical reports

This Technical Report documents the physical and hydrological characteristics of a farmland site on the Esperance Sandplain. The site was located on 'Belalie Farm East' 110 km east of the town of Esperance in the locality of Howick (AMG 488900, 6277500) The site was typical of the sandplain landsystem which covers 35% (0.72 million ha) of the Esperance Agricultural Region. The farm was cleared over a number of years beginning in the 1970's and an extensive network of windbreaks established.


Magnetostratigraphy Of Cueva Del Aleman, Isla De Mona, Puerto Rico And The Species Duration Of Audobon's Shearwater, Bruce C. Panuska, John M. Mylroie, Darrell Armentrout, Donald A. Mcfarlane Jan 1998

Magnetostratigraphy Of Cueva Del Aleman, Isla De Mona, Puerto Rico And The Species Duration Of Audobon's Shearwater, Bruce C. Panuska, John M. Mylroie, Darrell Armentrout, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Magnetostratigraphic analysis of deposits exposed in Cueva del Aleman shows two reversed and two normal chronozones. The lower normal polarity event is observed in a clastic dike and probably predates initial cave formation. Sediments deposited inside the cave proper show a R-N-R sequence and probably date to at least 1.8 Ma. A fossiliferous clastic dike contains normal polarity with an overlying reversed magnetozone. Audubon’s Shearwater (bird) bones occur in the dike, which is tentatively correlated with the lower N polarity zone predating cave formation. If this correlation is correct, the Audubon’s Shearwater (Puffinus lherminieri) range can be extended back to …


An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig Jan 1998

An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig

Technical Bulletins

The inventory and condition survey of the Sandstone-Yalgoo-Paynes Find area, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1992 and 1993, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the area’s natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about …


The Effects Of Hydrilla Infestation On Selected Wintering Waterfowl: Santee Copper Lake System, South Carolina, William Davis May 1997

The Effects Of Hydrilla Infestation On Selected Wintering Waterfowl: Santee Copper Lake System, South Carolina, William Davis

Masters Theses & Specialist Projects

Hydrilla is an exotic aquatic weed that was introduced into Florida in the 1950's. Since that time it has spread rapidly from lake to lake throughout the southeast and beyond. The Santee Cooper lake system in eastern South Carolina was infested with the weed in the early 1980's. Since that time lake managers have sought ways to eliminate the aquatic plant and have succeeded to a great extent through the use of sterile grass carp as a biological control agent. This paper, however, contains evidence to support the view that hydrilla is actually a beneficial habitat for many species on …


The Effects Of Organic Matter Rich Topsoil On The Germination Growth And Metal Uptake Of Corn (Zea Mays) Grown In Flue Dust Contaminated Soil, Christopher Allen Impellitteri Apr 1997

The Effects Of Organic Matter Rich Topsoil On The Germination Growth And Metal Uptake Of Corn (Zea Mays) Grown In Flue Dust Contaminated Soil, Christopher Allen Impellitteri

OES Theses and Dissertations

The large biomass of corn (Zea mays) and promising results from a previous experiment (Chlopecka and Adriano, 1995) concerning metal uptake by corn indicate that corn may be a good candidate for phytoremediation of trace metal contaminated soil. Appling soil (acid, thermic, typic paleudult) was treated with increasing levels of a metal rich flue dust based on Zn concentration (0, 150, 300, 600, 1200, and 2400 mg/kg). Four replicates at each Zn treatment level were either limed to pH 6.3-6.5 and covered with a two inch thick layer of organic matter rich topsoil (OM), unlimed and covered with …


Marine Pore-Water Sulfate Profiles Indicate In Situ Methane Flux From Underlying Gas Hydrate, Walter S. Borowski, Charles K. Paull, William Ussler Iii Jul 1996

Marine Pore-Water Sulfate Profiles Indicate In Situ Methane Flux From Underlying Gas Hydrate, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Marine pore-water sulfate profiles measured in piston cores are used to estimate methane flux toward the sea floor and to detect anomalous methane gradients within sediments overlying a major gas hydrate deposit at the Carolina Rise and Blake Ridge (U.S. Atlantic continental margin). Here, sulfate gradients are linear, implying that sulfate depletion is driven by methane flux from below, rather than by the flux of sedimentary organic matter from above. Thus, these linear sulfate gradients can be used to quantify and assess in situ methane flux, which is a function of the methane inventory below.


Bones Of Puffinus Lherminieri Lesson (Aves: Procellaridae) And Two Other Vertebrates From Cueva Del Agua, Mona Isalnd, Puerto Rico (West Indies), Angel M. Nieves-Rivera, John M. Mylroie, Donald A. Mcfarlane Jan 1995

Bones Of Puffinus Lherminieri Lesson (Aves: Procellaridae) And Two Other Vertebrates From Cueva Del Agua, Mona Isalnd, Puerto Rico (West Indies), Angel M. Nieves-Rivera, John M. Mylroie, Donald A. Mcfarlane

WM Keck Science Faculty Papers

From a dive in Cueva del Agua, Mona Island, Puerto Rico, twelve un-mineralized bones of Puffinus Lherminieri Lesson, one of Cyclura stejnegeri Stejneger, and one of Moormops blainvilii Leach were collected. The subfossil evidence confirms that P. Lherminieri was a common species on Mona Island. Cyclura stejnegeri and M. blainvilii probably became trapped and died in the pool chamber.


Land Management Report For The Kent River Catchment, Sue Kelly Jan 1995

Land Management Report For The Kent River Catchment, Sue Kelly

Natural resources published reports

The Kent River Catchment is located in the South-West of Western Australia, approximately between latitudes 34° 15' and 35° 10' South and longitudes 116° 45" and 117° 50° East. The north-eastern boundary of the catchment stretches to the Albany Highway at Tenterden, and from there the catchment curves towards Rocky Gully before continuing to the South Coast (Figure 1.1.1). The catchment is located within the Shires of Cranbrook, Plantagenet and Denmark.

The Kent River Catchment is part of Basin 604, which is the Water Authority descriptor for the Kent, Bow and Kordabup River catchments collectively. Basin 604 has a total …


An Inventory And Condition Survey Of The Murchison River Catchment, Western Australia, Peter James Curry, A L. Payne, K A. Leighton, P Hennig, D A. Blood Jan 1994

An Inventory And Condition Survey Of The Murchison River Catchment, Western Australia, Peter James Curry, A L. Payne, K A. Leighton, P Hennig, D A. Blood

Technical Bulletins

The inventory and condition survey of the Murchison River catchment and surrounds, undertaken by the Department of Agriculture between 1985 and 1988, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed by field work during 1985-88 …


An Inventory And Condition Survey Of Rangelands In The North-Eastern Goldfields, Western Australia, H J. Pringle, S A. Gilligan, A M E Van Vreeswyk Jan 1994

An Inventory And Condition Survey Of Rangelands In The North-Eastern Goldfields, Western Australia, H J. Pringle, S A. Gilligan, A M E Van Vreeswyk

Technical Bulletins

The inventory and condition survey of the north-eastern Goldfields, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1988 and 1990, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about 100 …


The Mobrup Catchment Working Plan - A Resource Inventory And Strategies, Steven Garrad Jun 1993

The Mobrup Catchment Working Plan - A Resource Inventory And Strategies, Steven Garrad

Soil conservation survey collection

The Mobrup LCDC has persevered for three years with its efforts to produce a catchment plan. They readily acknowledge that their work is just beginning as they now wrestle with this working plan to form something which will have application on each individual's enterprise to ensure a sustainable future for this catchment.This report is a collation of their ideas, an inventory of works done in the catchment and the best advice which research and local knowledge can provide.


Geological Field Guide To The Cedar Point Biological Station, Keith County, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian Feb 1993

Geological Field Guide To The Cedar Point Biological Station, Keith County, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian

School of Natural Resources: Faculty Publications

This field guide was produced by staff members of the Conservation and Survey Division of the University of Nebraska originally in 1979 at the request of Dr. Brent Nickol, former Director of the Cedar Point Biological Station. It is an introduction to the geologic history and paleoecology of the Cedar Point area intended for students, staff, and other persons using the camp. This revision has been made some 15 years after the first version to reflect changes in ideas resulting from new data collected during that time.

Users of this guide should take care when studying the rock exposures described …


Distribution Of Foraminifera And Pollen In Coastal Depositional Environments Of The Southern Delmarva Peninsula, Virginia, U.S.A., Han Jun Woo Jan 1992

Distribution Of Foraminifera And Pollen In Coastal Depositional Environments Of The Southern Delmarva Peninsula, Virginia, U.S.A., Han Jun Woo

OES Theses and Dissertations

The coastal zone of the southern Delmarva Peninsula exhibits a wide variety of barrier island system subenvironments. This study investigates whether 20 a priori subenvironments can be distinguished from each other on the basis of abiotic environmental variables, pollen assemblages, living foraminiferal populations, and total (living plus dead) foraminiferal assemblages.

The physical data collected from the coastal zone were subjected to canonical variate analysis which discriminated 83% of the stations in 19 groups. These groups were clustered into two internally overlapping sets which represented the inside and outside of the inlet.

Twenty-two pollen types were found in low-energy marsh and …


Manual Of Field Techniques In Hydrology, Department Of Agriculture, Western Australia. Division Of Resource Management Jan 1991

Manual Of Field Techniques In Hydrology, Department Of Agriculture, Western Australia. Division Of Resource Management

Agriculture reports

No abstract provided.


Land Management Manual. Merredin Advisory District, F. Frost, M Howell Jul 1990

Land Management Manual. Merredin Advisory District, F. Frost, M Howell

Natural resources published reports

Farming by soil type recognizes that each major soil unit has specific land use capabilities. 'When developing a farm management programme, understanding and appreciating the productive potential and degradation hazard of each soil unit ensures that production systems can be developed which are 'sustainable. The aim of this land management manual is to describe the climatic and geological features of the district and provide definitions of each of the major soil units and 'current management recommendations. The material is designed to be used as an information base for farm planners.

Thes oil units described are for the Merredin advisory district …


A Revision Of The North American Papillose Allocreadiidae (Digenea) With Independent Cladistic Analyses Of Larval And Adult Forms, Janine N. Caira Oct 1989

A Revision Of The North American Papillose Allocreadiidae (Digenea) With Independent Cladistic Analyses Of Larval And Adult Forms, Janine N. Caira

Bulletin of the University of Nebraska State Museum (1924–2023)

Adult specimens of all 19 North American species of papillose allocreadiids were examined. A description and figure is given for the adult of each species; details of the cirrus sacs are presented for most spesies for the first time. Descriptions were emended where necessary and judgments were made on synonymies. Scanning electron micrographs of the oral sucker of 10 species are presented as is a new key to the 19 species. A cladistic analysis was performed on the group based on adult characters. The analysis indicated that the group is monophyletic on the basis of the ventral papillae associated with …


An Inventory And Condition Survey Of Rangelands In The Ashburton River Catchment, Western Australia, A A. Mitchell, A L. Payne, W F. Holman Jan 1988

An Inventory And Condition Survey Of Rangelands In The Ashburton River Catchment, Western Australia, A A. Mitchell, A L. Payne, W F. Holman

Technical Bulletins

The inventory and condition survey of rangelands in the Ashburton River catchment, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1976 and 1978, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed …


A Monograph Of The Genus Polyphylla Harris In America North Of Mexico (Coleoptera: Scarabaeidae: Melolonthinae), Ronald M. Young Jan 1988

A Monograph Of The Genus Polyphylla Harris In America North Of Mexico (Coleoptera: Scarabaeidae: Melolonthinae), Ronald M. Young

Bulletin of the University of Nebraska State Museum (1924–2023)

The North American species of the genus Polyphylla Harris, 1841, are defined and revised for the first time since Fall (1928). All name bearing types were examined except those of P. oklahomensis Hatch and P. subvittata LeConte (synonyms of P. hammondl), which are lost. A lectotype is designated for P. gracilis Horn, and neotypes for P. decemlineata (Say), P. occidentalis (L.), and P. variolosa (Hentz). New synonyms of P. decemlineata are P. comstockiana von Bloeker, P. matrona Casey, and P. potsiana Casey. New synonyms of P. crinita …


Depth Profiles And Soil Textures Of The Vernal Pools Of The Santa Rosa Plateau Preserve, Riverside County, California, Ralph Charles Workman Jr. Dec 1987

Depth Profiles And Soil Textures Of The Vernal Pools Of The Santa Rosa Plateau Preserve, Riverside County, California, Ralph Charles Workman Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this project was to study the edaphic and topographic characteristics of the 13 vernal pools on the Santa Rosa Plateau Preserve, thus documenting the role soil texture plays in vernal pool formation.

Several field and laboratory procedures were used to demonstrate that there is a higher percentage of clay present within vernal pools than in soils outside the margin of the pools, for 11 out of the 13 pools. Statistical tests showed that the percentage of clay was highly significant within the center soil of the pool as compared to the soil outside the margin of the …